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(searched for: The Features of Electronic Conduction in InAs)
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E. Khutsishviliis, Z. Chubinishvili, G. Kekelidze, I. Kalandadze, T. Qamushadze, M. Metskhvarishvili
European Journal of Engineering and Technology Research, Volume 6, pp 10-13; doi:10.24018/ejers.2021.6.3.2401

Abstract:
The electrical properties of n-type crystals of InAs compound, grown from stoichiometric melt by the horizontal zone melting method, have been investigated in the temperature range of 4.2 K-300 K before and after fast neutron irradiation up to high integral fluences of 2×1018n∙cm-2. At a fixed temperature electrons concentration (n) increases almost by one order during irradiation, and practically does not change with increasing of temperature. n increases only slightly by increasing of temperature near 300 K, both before and after irradiation. When ≥ 4×1018cm-3 the change of during irradiation is negligible. Comparison of experimental data of mobility with theory shows that the privileged scattering mechanism of electrons at 300 K is scattering on optical phonons in InAs with 1016-1017 cm-3 and scattering on ions of impurity in InAs with n~1018-1019 cm-3. The analysis shows that during irradiation point type scattering centers of donor-type structural defects with shallow levels in the forbidden zone appear. Consequently, the mobility decreases during irradiation. At 300 K in sample with electrons concentration of 3×1016 cm-3 the mobility decreases by 5 times after irradiation, which is equivalent to the formation of 1.5×1019cm-3 charged point scattering centers.
Dongchen Chai, Jinxing Hu, Chengde Li, Zhijian Li, Hongming Yang, Jinbao Tang, Weili Gong,
Published: 1 April 2021
Materials Letters, Volume 288; doi:10.1016/j.matlet.2021.129368

The publisher has not yet granted permission to display this abstract.
Habibur Rahman, Emdadul Haque Chowdhury, Didarul Ahasan Redwan,
Published: 1 April 2021
Computational Materials Science, Volume 190; doi:10.1016/j.commatsci.2020.110272

Abstract:
Two-dimensional germanene has provided a cornucopia of new functionalities in the field of nanotechnology owing to its remarkable electronic and thermoelectric attributes. The robust spin–orbit coupling and high carrier mobility give rise to many salient features including non-trivial topological properties, quantum spin-Hall state near room temperature, and topological superconductivity, rendering it an excellent contender for valleytronics, spintronics, and quantum computation. As such, an in-depth characterization of thermal and mechanical properties of germanene is crucial for its practical implication and efficient operation, which remains elusive. Here, we employed equilibrium molecular dynamics simulations utilizing Stillinger Weber potential to reveal the mechanical strength, melting temperature, and phonon thermal conductivity (PTC) of single-layer germanene nanoribbon (SLGeNR) and bilayer germanene nanoribbon (BiLGeNR). Effects of temperature, biaxial tensile and compressive strain, monovacancy defects, length and width of the nanoribbon on the PTC have been rigorously investigated. It has been found that PTC of SLGeNR could be substantially reduced by BiLGeNR. Our simulation results suggest that PTC of SLGeNR demonstrates an inverse relation with temperature, biaxial compressive strain, and monovacancy defects while biaxial tensile strain, length and width of the nanoribbon increases the PTC of SLGeNR significantly. To understand the PTC more profoundly, phonon density of state (PDOS) profiles have been studied. The BiLGeNR demonstrates more tensile strength as well as melting temperature compared to SLGeNR. This study offers a comprehensive guideline for engineering the TC as well as discloses important mechanical and melting characteristics of the SLGeNR and BiLGeNR for a wide range of applications in flexible nano-electronics and thermoelectric nanodevices.
, Yumeng Tian, Zaiwen Lin, Qi Liu, , Rongrong Chen, Hongsen Zhang, Jun Wang
Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 614; doi:10.1016/j.colsurfa.2021.126189

The publisher has not yet granted permission to display this abstract.
M. A. Golovchin
Vysshee Obrazovanie v Rossii = Higher Education in Russia, Volume 30; doi:10.31992/0869-3617-2021-30-3-59-75

Abstract:
In 2016-2018 the state in Russia adopted a package of program documents, which implies the transfer of education to the large-scale introduction of digital technologies. This phenomenon has been called “digitalization of education”. In scientific literature, electronization and digitalization are increasingly called one of the institutional traps for the development of Russian universities, since the corresponding institutional environment has not yet been formed due to the forced nature of innovations. As a result, the processes of introducing new technologies into education are still not regulated. Within the framework of the purpose of the study, the manifestations of the trap of electronization and digitalization of Russian higher education were analyzed on the basis of sociological data, and the theoretical modeling of the process of adaptation of educational agents to the institution of digitalization was carried out. In the course of the study, the approaches were summarized that have been developed in discussions on educational digitalization. The article presents the author’s vision of the studied phenomenon as an institutional trap; as well as understanding of the institutional features and characteristics of electronization and digitalization in education. The research method is the analysis of estimates obtained in the course of an expert survey which was conducted by the Vologda Scientific Center of the Russian Academy of Sciences among the representatives of the teaching staff of state universities in the Vologda region. In the course of this analysis, the indicators of educational digitalization as an effective innovation were clarified such as an increased accessibility of educational resources; simplification of communication and the process of transferring knowledge from teacher to student; increased opportunities for training specialists for the new (digital) economy; improving the quality of education in universities, etc. Based on the results of the empirical study, it has been determined that the conditions for the development of digitalization in Russian universities are currently ambiguous, which is closely related to the level of competitiveness of the educational organization. The scientific novelty of the research consists in the presentation of an original matrix describing the process of university employees adaptation to the conditions of digital transformation of education. The matrix is proposed on the basis of a sociological analysis of the impact of the trap of electronization and digitalization on the activities of educational agents. The matrix can be taken into account in the practice of higher education management.
Yuxi Wei, Xiao Rong Luo, Yuan Gang Wang, Juan Lu, Zhuolin Jiang, Jie Wei, Yuanjie Lv, Zhihong Feng
IEEE Transactions on Power Electronics, pp 1-1; doi:10.1109/tpel.2021.3069918

The publisher has not yet granted permission to display this abstract.
Olena Stashchuk, Rostyslav Martyniuk
VUZF Review, Volume 6, pp 79-86; doi:10.38188/2534-9228.21.6.08

The publisher has not yet granted permission to display this abstract.
Sihui Li, Jiwu Xin, Wang Li, Yang Tao, Tian Xu, Bo Xiao, Yubo Luo, Qinghui Jiang,
Published: 25 March 2021
Journal of Alloys and Compounds, Volume 858; doi:10.1016/j.jallcom.2020.157634

The publisher has not yet granted permission to display this abstract.
Hong Hong, , Kyoung-Sik Moon, Xiong Yan, Ching-Ping Wong
Journal of Materials Science & Technology, Volume 67, pp 145-155; doi:10.1016/j.jmst.2020.06.033

The publisher has not yet granted permission to display this abstract.
Xiangyu Cao, Jie-Xiang Yu, Pengliang Leng, Changjiang Yi, Yunkun Yang, Shanshan Liu, Lingyao Kong, Zihan Li, Xiang Dong, Youguo Shi, et al.
Published: 17 March 2021
by ArXiv
Abstract:
Anomalous Hall effect (AHE) is the key transport signature unlocking topological properties of magnetic materials. While AHE is usually proportional to the magnetization, the nonlinearity suggests the existence of complex magnetic and electron orders. Nonlinear AHE includes the topological Hall effect (THE) that has been widely used to identify the presence of spin chirality in real space. But it can in principle be induced by band structure evolution via Berry curvatures in the reciprocal space. This effect has been largely overlooked due to the intertwined mechanisms in both real and reciprocal spaces. Here, we observed a giant nonlinear AHE with the resistivity up to 383.5 uohm cm, contributing unprecedentedly 97% of the total Hall response in EuCd2As2. Moreover, it can be further enhanced by tilting the magnetic field 30{\deg} away from [001] direction, reaching a large anomalous Hall angle up to 21%. Although it shows exactly the same double-peak feature as THE, our scaling analysis and first-principles calculations reveal that the Berry phase is extremely sensitive to the spin canting, and nonlinear AHE is a consequence of band structure evolution under the external magnetic fields. When the spins gradually tilt from the in-plane antiferromagnetic ground state to out-of-plane direction, band crossing and band inversion occur, introducing a bandgap at {\Gamma} point at a canting angle of 45{\deg}. That contributes to the enhancement of Berry curvature and consequently a large intrinsic Hall conductivity. Our results unequivocally reveal the sensitive dependence of band structures on spin tilting process under external magnetic fields and its pronounced influence on the transport properties, which also need to be taken into consideration in other magnetic materials.
, Hassan Karimi-Maleh, Fatih Sen
Published: 17 March 2021
Frontiers in Chemistry, Volume 9; doi:10.3389/fchem.2021.648920

Abstract:
Editorial on the Research TopicAdvances in Analytical Features of Electrochemical Methods for the Analysis of Complicated Real Samples The aim of this topic was presentation of several features of electrochemical methods for analysis of real samples. In the last few decades, with the technical progress of electrochemical devices, much attention has been paid to electrochemical methods for analysis of different species. However, like other analytical methods, there has been the challenge of analyzing real samples with complex matrices and several interferences. Several techniques have been presented to improve selectivity and other figures of merit. Most of them are based on modification of electrodes and creating selective electoactive sites on the surface of electrodes (Fouladgar, 2016). In addition, the modifiers may have electrocatalytic effect on the redox of analyte. On the other hand, application of nanomaterials has become popular because of increasing the active surface area of electrodes and consequently increasing sensitivity (Negahban et al., 2017). Papers in this research topic, present various aspects of new methods and techniques, which have been applied for analysis of complicated samples. As mentioned above, nanomaterials are widely used for modification of electrodes. Metal oxides are among the nanomaterials that used for this purpose. They are applied single or combination with other nanomaterials (Fouladgar and Mohammadzadeh, 2014). Naghian et al. have exhibited that using nanostructures including CdO and magnetic Fe3O4 nanoparticles can improve kinetics of the electron transfer process on the electrode. They applied this effect to determine an antiviral drug in urine, plasma and tablet. Moreover, different inherent redox potential of species or different interaction of species with electrode modifier can make simultaneous measurement possible. Accordingly, Pan et al. have reported an electrochemical method for simultaneous determination of Ascorbic acid, dopamine and uric acid in pharmaceutical samples. To reduce utilizing chemical reagents, Jing et al. have used Plectranthus amboinicus leaf extract for biosynthesis of gold nanoparticles. They determined nicotine in tobacco products by modifying glassy carbon with these nanoparticles. Feng et al. presented an electrochemical method for determination of ursolic acid in a fruit extract (Ligustrum lucidum) which has many biological effects. Deposited composite of boron nitride nanosheets and Pt nanoparticles on the surface of glassy carbon, exhibits catalytic activity toward ursolic acid oxidation. In addition to the analytical aspects of a sensor, biocompatibility of the sensor is important for analysis of clinical samples. Naderi Asrami et al. have prepared a biocompatible electrode containing glucose oxidase enzyme, which was covalently immobilized on a multi-layer thin film electrode. This electrode can be used to direct determination of glucose in blood serum. Hou et al. presented another aspect of electrochemical methods based on changing piezoelectric properties of quartz crystal by deposition of analyte on it. They immobilized antibodies against B. bifidum on an Au chip and used it as an immunosensor. This kind of sensor has both sensitivity of quartz crystal and specification of immune response between antigen and antibody. Shen et al. have described application of signal amplification technique for creating an immunosensor to determine alpha-fetoprotein in serum samples. They used an immune complex consisting of alpha-fetoprotein antibody and horseradish peroxidase for immune response. In addition, the catalytic effect of a nanocomposite containing graphene oxide, methylene blue and gold nanoparticles has been applied for fabrication of this immunosensor. One area in which application of electrochemical methods has received much attention is analysis of pharmacological and biological samples. Electrochemistry has presented simple, fast and sensitive methods to analyze these samples. Alizadeh et al. have used effects of modifying electrodes with different nanomaterials and ionic liquid. Increasing conductivity of carbon paste subsequently increases the redox current and also increases sensitivity of the method. This technique has provided methods for determination of drugs in pharmaceutical samples (Alizadeh et al.). Remote sensing is important for monitoring chemical species in the environment. Kim et al. have proposed a wireless sensing system for real time measuring chloride ion. They have succeeded in reducing electrolyte leakage by modifying the structure of the electrode. Finally, the effect of species on the profile of electrochemical oscillation systems has been used for identification chemical compounds. Yan et al. have been shown that recording the oscillation profile of an oscillation reaction in the presence of different herbal medicine can be used as a fingerprint for identification of them. MF drafted the manuscript. All co-authors contributed to review the manuscript. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. We want to thank all the authors and reviewers for their valuable contributions to this research topic, and we hope that this collection of articles will be helpful for researchers and students. Fouladgar, M. (2016). Application of ZnO nanoparticle/ion liquid modified carbon paste electrode for determination of isoproterenol in pharmaceutical and biological samples. J. Electrochem. Soc. 163, B38–B42. doi:10.1149/2.0611603jes CrossRef Full Text | Google Scholar Fouladgar, M., and Mohammadzadeh, S. (2014). Determination of methimazole on a multiwall carbon nanotube titanium dioxide nanoparticle paste electrode. Anal. Lett. 47, 763–777. doi:10.1080/00032719.2013.855782 CrossRef Full Text | Google Scholar Negahban, S., Fouladgar, M., and Amiri, G....
, Alexander Wheeldon, Carina Hendler, Alexander Fian, Roman Trattnig
Published: 12 March 2021
Nanotechnology, Volume 32; doi:10.1088/1361-6528/abe902

Abstract:
GaAs compound-based electronics attracted significant interest due to unique properties of GaAs like high electron mobility, high saturated electron velocity and low sensitivity to heat. However, GaAs compound-based electronics demand a significant decrease in their manufacturing costs to be a good competitor in the commercial markets. In this context, copper-based nanoparticle (NP) inks represent one of the most cost-effective metal inks as a proper candidate to be deposited as contact grids on GaAs. In addition, Inkjet-printing, as a low-cost back-end of the line process, is a flexible manufacturing method to deposit copper NP ink on GaAs. These printed copper NP structures need to be uncapped and fused via a sintering method in order to become conductive and form an ohmic contact with low contact resistivity. The main challenge for uncapping a copper-based NP ink is its rapid oxidation potential. Laser sintering, as a fast uncapping method for NPs, reduces the oxidation of uncapped copper. The critical point to combine these two well-known industrial methods of inkjet printing and laser sintering is to adjust the printing features and laser sintering power in a way that as much copper as possible is uncapped resulting in minimum contact resistivity and high conductivity. In this research, copper ink contact grids were deposited on n-doped GaAs by inkjet-printing. The printed copper ink was converted to a copper grid via applying the optimized settings of a picosecond laser. As a result, an ohmic copper on GaAs contact with a low contact resistivity (8 mΩ cm2) was realized successfully.
, , Julia Richter, César Ernesto Sobrero, Sebastian Degener, , ,
Published: 10 March 2021
by Wiley
Advanced Engineering Materials; doi:10.1002/adem.202100018

Abstract:
Additive manufacturing (AM) processes such as electron beam melting (EBM) are characterized by unprecedented design freedom. Topology optimization and design of the microstructure of metallic materials are enabled by rapid progress in this field. The latter is of highest importance as many applications demand appropriate mechanical as well as functional material properties. For instance, biodegradable implants have to meet mechanical properties of human bone and at the same time guarantee adequate cytocompatibility and degradation rate. In this field, pure iron has come into focus in recent studies due to its low toxicity. Hierarchical microstructures resulting from the EBM solidification processes and intrinsic heat treatment, respectively, allow for an adjustment of the degradation behavior and may promote enhanced fatigue strength. Herein, commercially pure iron (cp‐Fe) is processed by EBM. Microstructural analysis as well as an evaluation of the cyclic mechanical material properties are conducted. The results are compared to a hot‐rolled (HR) reference material. A contradiction observed as the EBM‐processed cp‐Fe (EBM Fe) shows lower ultimate tensile strength under monotonic loading but improved fatigue properties compared to the HR Fe. It is revealed that such a unique behavior originates from prevailing microstructural features in the EBM as‐built condition.
M. I. Naher,
Scientific Reports, Volume 11, pp 1-21; doi:10.1038/s41598-021-85074-z

Abstract:
In recent days, study of topological Weyl semimetals have become an active branch of physics and materials science because they led to realization of the Weyl fermions and exhibited protected Fermi arc surface states. Therefore, topological Weyl semimetals TaX (X = P, As) are important electronic systems to investigate both from the point of view of fundamental physics and potential applications. In this work, we have studied the structural, elastic, mechanical, electronic, bonding, acoustic, thermal and optical properties of TaX (X = P, As) in detail via first-principles method using the density functional theory. A comprehensive study of elastic constants and moduli shows that both TaP and TaAs possesses low to medium level of elastic anisotropy (depending on the measure), reasonably good machinability, mixed bonding characteristics with ionic and covalent contributions, brittle nature and relatively high Vickers hardness with a low Debye temperature and melting temperature. The minimum thermal conductivities and anisotropies of TaX (X = P, As) are calculated. Bond population analysis supports the bonding nature as predicted by the elastic parameters. The bulk electronic band structure calculations reveal clear semi-metallic features with quasi-linear energy dispersions in certain sections of the Brillouin zone near the Fermi level. A pseudogap in the electronic energy density of states at the Fermi level separating the bonding and the antibonding states indicates significant electronic stability of tetragonal TaX (X = P, As).The reflectivity spectra show almost non-selective behavior over a wide range of photon energy encompassing visible to mid-ultraviolet regions. High reflectivity over wide spectral range makes TaX suitable as reflecting coating. TaX (X = P, As) are very efficient absorber of ultraviolet radiation. Both the compounds are moderately optically anisotropic owing to the anisotropic nature of the electronic band structure. The refractive indices are very high in the infrared to visible range. All the energy dependent optical parameters show metallic features and are in complete accord with the underlying bulk electronic density of states calculations.
Papri Mondal, Jit Satra, , Gopala Ram Bhadu,
ACS Catalysis, Volume 11, pp 3687-3703; doi:10.1021/acscatal.0c05638

The publisher has not yet granted permission to display this abstract.
Carolyn Mary Ecelbarger
Published: 8 March 2021
Frontiers in Physiology, Volume 12; doi:10.3389/fphys.2021.650503

Abstract:
According to the World Health Organization, the global presence of type 2 diabetes (T2D) rose sharply from 4.7 to 8.5% of the population between the years 1980 and 2014 (Emerging Risk Factors Collaboration et al., 2010). Moreover, T2D is associated with a 30–50% risk of diabetic nephropathy (DN) (Gheith et al., 2016). Given a world population of ~7.8 billion (December 2020) (Worldometer, 2020), we may expect as many as 300–400 million affected persons. DN is the leading cause of end-stage renal disease (ESRD) (Toth-Manikowski and Atta, 2015). Currently renal transplantation is the treatment of choice for patients with ESRD due to improvements in graft survival; however, the wait for an available organ may extend to 3–5 years (Allen et al., 2018; Clayton et al., 2018). Dialysis is clearly not the answer, at least as it is currently employed, as the 5-year survival rate for patients receiving some form of hemodialysis hovers only at around 20–40% (Huff, 2020). Moreover, the cost of treating these subjects is phenomenal, and many cannot gain access to or afford any type of treatment. Only a handful of new innovative and efficacious strategies to combat DN has made it to the clinic in the last 50 years. Why is this the case? It is partly because we do not fully understand the problem. The kidney is clearly a complicated organ derived from three overlapping sequential systems—the pronephros, the mesonephros, and the metanephros, which are all derived from the urogenital ridge (Qiaggin and Kreidberg, 2006). The kidney conducts a variety of seemly unrelated tasks utilizing a variety of specialized cell types extending along the renal tubule. The 3-D architecture of the kidney is essential in its role in regulating whole-body fluid balance, acid-base homeostasis, blood pressure control, excretion of toxic substances, and reabsorption of vital filtered substances. In the process of cleaning the blood, the proximal tubule (PT) is tasked with reabsorbing and recycling a number of substances, e.g., glucose, amino acids, electrolytes, and water, which would otherwise be lost. Urine is concentrated by the use of energy to generate a cortico-medullary sodium and urea gradient in the interstitium, allowing for passive reabsorption of water, regulated tightly by vasopressin. All of these aspects of normal kidney function can be compromised by DN. DN may be described as a “perfect storm” involving inflammation, fibrosis, and oxidative stress. Histologically, it has a number of features that distinguish it from other forms of renal disease. For example, Kimmelstein-Wilson lesions, composed of nodular, circular, scar tissue, will form in the glomerulus. Other features include an expanded mesangium and increased mesangial cell number in the glomerulus. The basement membranes of the glomerulus and tubules become thicker (up to 3X) with deposition of collagen, albumin, and IgG along their borders. There is an accumulation of the advanced glycation end product (AGES) due to the partially reduced sugar moieties. AGES increases protein cross-linking, inflammation, and oxidative stress. Foot processes in the glomerulus merge. A common theme underlying the pathology of DN can be broadly thought of as dysregulated utilization of energy. We can treat DN both by treating T2D itself, i.e., tightly controlling blood glucose levels, as well as, via strategies that short-circuit the effects of T2D on the kidney. For purposes of this article, I will focus primarily on the latter. First, I will discuss the specific challenges of DN in regard to mechanisms of the disease, and standards of care. Second, I will discuss some newer medication strategies that are promising. Finally, I will turn to developing approaches to treat the patient when the kidneys have failed, e.g., xenotransplantation, organ regeneration, and portable artificial kidneys. T2D is associated with a number of physiological changes, the most obvious being hyperglycemia. One of the main targets of hyperglycemia in the kidney, as well as other organs, is the vasculature (Magee et al., 2017). Endothelial dysfunction, impaired nitric oxide generating capacity, as well as, atherosclerotic plaque formation contribute to impaired blood flow and altered renal hemodynamics. Hyperglycemia is also associated with hyperinsulinemia early in the course of T2D (Tiwari et al., 2007b). We have shown insulin receptor expression is reduced in the cortex and medulla of the kidney in hyperinsulinemic, obese, and T2D rats (Tiwari et al., 2007a). Nonetheless, some aspects of insulin signaling may remain intact in the kidney, in particular those acting through the insulin receptor substrate type 2 (IRS-2) (Ecelbarger, 2020). This can lead to inappropriate upregulation of sodium reabsorption and gluconeogenesis in the PT (Nakamura et al., 2015, 2019). In the kidney per se, the metabolism of epithelial and endothelial cells is altered in an environment in which glucose levels are higher than the norm, i.e., 5.5 mM. Elevated cellular glucose levels lead to a rise in oxidative phosphorylation by the mitochondria. This liberates oxidative radicals including superoxide, which may overwhelm the normal anti-oxidative complement of the mitochondria, e.g., manganese superoxide dismutase (Burgos-Moron et al., 2019). Reactive oxygen species (ROS) can damage cellular DNA, lipids, and proteins, as well as other organelles, such as the endoplasmic reticulum (ER). It appears that mitochondrial DNA, which codes for many of the components of the electron transport chain, is particularly susceptible to ROS damage (Burgos-Moron et al., 2019). Damage to the ER can lead to misfolded proteins, a critical step in their biogenesis (Zeeshan et al., 2016). Inflammation in DN is initiated as a protective response to early tissue injury or cell death (Perez-Morales et al., 2019). Major players in the inflammation associated with DN (which can include both systemic...
, Hailong Yue, Juan Xia, Congying Ren, Shanming Gao
Published: 1 March 2021
by Wiley
ChemistrySelect, Volume 6, pp 2029-2035; doi:10.1002/slct.202100062

The publisher has not yet granted permission to display this abstract.
Q.-B. Nguyen, V.-H. Nguyen, C. Perrot, A. Rios de Anda, E. Renard,
Published: 1 March 2021
Materials Today Communications, Volume 26; doi:10.1016/j.mtcomm.2020.101938

The publisher has not yet granted permission to display this abstract.
, Caiyun Yu, A. Abu-Siada, HongBin Li, Zhenxing Li, Tao Zhang, Yanchun Xu
International Journal of Electrical Power & Energy Systems, Volume 126; doi:10.1016/j.ijepes.2020.106611

The publisher has not yet granted permission to display this abstract.
Shaowen Li, Shu Zhang, Changchun Sun, Wenyu Zhao, Ting Zhao, Min Zhang, Helin Wang,
Published: 1 March 2021
Energy Storage Materials, Volume 35, pp 378-387; doi:10.1016/j.ensm.2020.11.024

The publisher has not yet granted permission to display this abstract.
Published: 1 March 2021
Results in Physics, Volume 22; doi:10.1016/j.rinp.2021.103844

Abstract:
There has been an increasing number of research and development activities focusing on the use of different glass systems for their nuclear radiation shielding features. In this study a simulation study has been carried out at a wide photon energy region in order to investigate the radiation protection feature of bismuth borate glasses. This study has been conducted to evaluate the proficiency level of six different glass systems (70-x)B2O3 + xBi2O3 + 15ZnO + 15Na2O (where x = 0, 5, 10, 15, 20 and 25 mol%) exposed to photon, charged particle (H1) and (He+2) and neutron. For this investigation, transmission factors (TF), mass attenuation coefficient (MAC), half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff), effective electron density (Neff) have been computed. The results confirm that the parameters of the examined glasses MAC, HVL, TVL, MFP, Zeff, and Neff are associated with photon energy and chemical composition. In addition, neutron effective cross-sections (∑R) have been computed for bismuth borates and it was seen a good harmony. The computations for present samples have been examined over a broad energy range from 0.01 to 20 MeV and theoretical results have been obtained by using MCNPX software for transmission factors. In addition, simulation results have been calculated with the WinXCom program. Furthermore, MSP and PR calculations of the bismuth borate glass have been performed to figure out the radiation shielding features. For that reason, the SRIM code has been used to simulate H1 and He+2 particles. Considering the results obtained from this research, which examines the radiation protection of bismuth borate glasses, indicates that the best shielding achievement (while the HVL, TVL, MFP, TF have the lowest and the highest (∑R) values) is reached at 25% Bi2O3. As can be seen in the results, the addition of bismuth affirms that the use of such glass systems improves the radiation protection feature. In particular, 25%Bi2O3 glass system has been proved to show superior shielding properties for gamma radiation in combination with charged particles. Since the glass sample with the highest bismuth additive is 25%Bi2O3, the most radiation protection effect is also seen in this example. The obtained material has a satisfactory radiation shielding property as bismuth is added to the mixture.
Published: 27 February 2021
Polymers, Volume 13; doi:10.3390/polym13050739

Abstract:
An efficient, green and reusable catalyst for organic pollutant wastewater treatment has been a subject of intense research in recent decades due to the limitation of current technologies. Cellulose based aerogel composites are considered to be an especially promising candidate for next-generation catalytic material. This project was conducted in order to evaluate the behavior and ability of green and reusable sugarcane bagasse aerogels to remove P-Nitrophesnol from waste-water aqueous. Co-Zeolitic imidazolate [email protected] sugarcane bagasse aerogels composite catalysts were successfully prepared via simple in situ synthesis. The structure of hybrid aerogels and their efficient catalyst in peroxymonosulfate (PMS) activation for the degradation of p-nitrophenol (PNP) was investigated. As a result, the hybrid aerogels/PMS system removed 98.5% of PNP (10 mg/L) within 60~70 min, while the traditional water treatment technology could not achieve this. In addition, through a free radical capture experiment and electron paramagnetic resonance (EPR), the degradation mechanism of PNP was investigated. Further research found that the hybrid aerogels can effectively activate PMS to produce sulfate ( SO 4 • − ) and hydroxyl ( OH • ). Both of them contributed to the degradation of PNP, and SO 4 • − plays a crucial role in the degradative process. The most important feature of hybrid aerogels can be easily separated from the solution. The obtained results showed that the outer coating structure of cellulose can stabilize Co-ZIF and reduce the dissolution of cobalt ions under complex reaction conditions. Moreover, the prepared hybrid aerogels exhibit excellent reusability and are environmentally friendly with efficient catalytic efficiency. This work provides a new strategy for bagasse applications and material reusability.
, S. AlFaify, R. Ahmed
The European Physical Journal Plus, Volume 136, pp 1-13; doi:10.1140/epjp/s13360-021-01197-2

The publisher has not yet granted permission to display this abstract.
, Yangtao Ou, Bao Zhang, Jindi Wang, , Mintao Wan, Guocheng Li, Wenyu Wang, Li Wang, , et al.
Journal of the American Chemical Society, Volume 143, pp 3143-3152; doi:10.1021/jacs.0c11753

The publisher has not yet granted permission to display this abstract.
Sheng Chen, Meng Wang, Changyou Shao, Feng Xu
Sustainability of Biomass through Bio-based Chemistry pp 61-89; doi:10.1201/9780429347993-3

The publisher has not yet granted permission to display this abstract.
Safia Kanwal, Sidra Nawaz, Muhammad Kamran Malik, Zubair Nawaz
Published: 12 February 2021
by IEEE
IEEE Access, Volume 9, pp 31638-31661; doi:10.1109/access.2021.3059312

Abstract:
Many websites over the Internet are producing a variety of textual data; such as news, research articles, ebooks, personal blogs, and user reviews. In these websites, the textual data is so large that the process of finding pertinent information by a user often becomes cumbersome. To overcome this issue, “Text-based Recommendation Systems (RS)” are being developed. They are the systems with the capability to find the relevant information in a minimal time using text as the primary feature. There exist several techniques to build and evaluate such systems. And though a good number of surveys compile the general attributes of recommendation systems, there is still a lack of comprehensive literature review about the text-based recommendation systems. In this paper, we present a review of the latest studies on text-based RS. We have conducted this survey by collecting literature from preeminent digital repositories, that was published during the period 2010-2020. This survey mainly covers the four major aspects of the textual based recommendation systems used in the reviewed literature. The aspects are datasets, feature extraction techniques, computational approaches, and evaluation metrics. As benchmark datasets carry a vital role in any research, publicly available datasets are extensively reviewed in this paper. Moreover, for text-based RS many proprietary datasets are also used, which are not available in the public. But we have consolidated all the attributes of these publically available and proprietary datasets to familiarize these attributes to new researchers. Furthermore, the feature extraction methods from the text are briefed and their usage in the construction of text-based RS are discussed. Later, various computational approaches that use these features are also discussed. To evaluate these systems, some evaluation metrics are adopted. We have presented an overview of these evaluation metrics and diagramed them according to their popularity. The survey concludes that Word Embedding is the widely used feature selection technique in the latest research. The survey also deduces that hybridization of text features with other features enhance the recommendation accuracy. The study highlights the fact that most of the work is on English textual data, and News recommendation is the most popular domain.
Shahin Nargesi, , Vahid Alipour, Masih Tajdini, Javad Salimi
Cardiovascular Drugs and Therapy pp 1-11; doi:10.1007/s10557-020-07130-6

The publisher has not yet granted permission to display this abstract.
Rafał Wawrzyńczak, Stanislaw Galeski, Jonathan Noky, Yan Sun, Claudia Felser, Johannes Gooth
Published: 9 February 2021
by ArXiv
Abstract:
The quasi-quantized Hall effect (QQHE) is the three-dimensional (3D) counterpart of the integer quantum Hall effect(QHE),exhibited only by two-dimensional (2D) electron systems. It has recently been observed in layered materials, consisting of stacks of weakly coupled 2D platelets. Yet, it is predicted that the quasi-quantized 3D version of the 2D QHE occurs in a much broader class of bulk materials, regardless of the underlying crystal structure. Here, we report the observation of quasi-quantized plateau-like features in the Hall conductivity of the n-type bulk semiconductor InAs. InAs takes form of a cubic crystal without any low-dimensional substructure. The onset of the plateau-like feature in the Hall conductivity scales with $\sqrt{2/3}k_{F}^{z}/\pi$ in units of the conductance quantum and is accompanied by a Shubnikov-de Haas minimum in the longitudinal resistivity, consistent with the predictions for 3D QQHE for parabolic electron band structures. Our results suggest that the 3D QQHE may be a generic effect directly observable in materials with small Fermi surfaces, placed in sufficiently strong magnetic fields.
Hailong Yang, , Pascal Boulet
Published: 7 February 2021
by Wiley
Journal of the Chinese Chemical Society; doi:10.1002/jccs.202000499

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Published: 3 February 2021
Journal of Nanomaterials, Volume 2021, pp 1-2; doi:10.1155/2021/5478156

Abstract:
Due to its semiconductive properties, silicon has been widely used and still represents the basis of electronics-related technologies. Despite having properties often very different from the pure element, silicon derivatives (e.g., SiO2, SiC, and silanes) are widely exploited as well in a variety of fields, ranging from photonic to biomedicine. Besides the traditional applications, the wide spreading of nanostructures, with their enhanced and in some respect unexpected properties, is now opening new perspectives for the possible uses of silicon and its derivatives. In this thematic special issue, our purpose was to highlight cutting-edge technologies and most modern applications related to these materials, especially at the nanoscale. We are glad to announce that the five original research papers published here, which we will briefly present in the following, all perfectly fit with our starting aim. Two of the papers focus on issues related to the crucial role of Si and its derivatives for nanoelectronic and nanophotonic applications, clarifying the synthetic aspects which can substantially improve the features of the final obtainable structures. In particular, R.B. Beck and K. Ber synthesized ultrathin silicon layers by the mean of plasma-enhanced chemical vapor deposition (PECVD), analysing the influence of each parameter (i.e., type of reactor, presence of specific gases, timeframe, and temperature) on the final product quality. The authors elucidated some of the effects and interactions between the studied process conditions, thus providing useful indications to achieve layers with the desired properties, especially in terms of crystallinity. H.-K. Shin and coworkers focused on the electrical and microstructural properties of Ni/C-faced 4H-n-SiC substrates, analysing the crucial effect of temperature on ohmic contacts. Briefly, the authors were able to demonstrate that by optimizing the thermal annealing it is possible to obtain a vertically oriented NiSi phase allowing the formation of ohmic contacts; on the other hand, the horizontal-type NiSi phase obtainable at higher temperatures results in the degradation of ohmic behaviour. Besides the electronic field, silicon and its derivatives are now recognized as useful intermediates for surface functionalization, nanostructure synthesis, and decoration. Within this context, Y. Wang and coworkers contributed to this special issue with two papers. The authors devoted their efforts to the development of rapid, efficient, and high-yield ways to obtain a new silane coupling agent, which was then fully characterized, also in terms of thermal stability. Being able to react at the same time with metal oxides and organic compounds, the synthesized thiohydrazide-iminopropyltriethoxysilane played a key role in the design and preparation of a drug carrier based on magnetic nanoparticles. As a proof of principle, the system was tested for loading doxorubicin and revealed excellent pH responsiveness for drug releasing. Finally, within the field of Si for energy production and storage, P.P. Prosini and coworkers developed an efficient synthetic strategy for Si nanowires to be used as anodes in lithium-ion batteries. By growing Si nanostructures directly on the current collector, the authors were able at the same time (i) to overcome the problem of the volumetric expansion occurring in the anode during lithium alloying and (ii) to guarantee an excellent electric contact without adding conducting binders to the electrode. Despite the linear capacity fade observed upon cycling, at different values of the charging current, the synthetized nanowires showed an exceptionally high-rate capability. Due to the importance of the topic and the relevance of the achieved results, we sincerely hope that the papers published in this special issue would be of high interest for all readers of the journal. The Lead Guest Editor and the Guest Editors declare that there is no conflict of interest. We thank all authors for their valuable work and the referees for their efforts in carefully reviewing the manuscripts. Francesca A. ScaramuzzoArántzazu González-CampoAlessandro Dell’Era Copyright © 2021 Francesca A. Scaramuzzo et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abdul Kareem K. Soopy, Adel Najar, Florent Ravau, Dalvaver H. Anjum
2021 6th International Conference on Renewable Energy: Generation and Applications (ICREGA) pp 21-24; doi:10.1109/icrega50506.2021.9388283

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Jiufeng Wu, Tao Yang, Jianliang Lyu
Journal of Physics: Conference Series, Volume 1815; doi:10.1088/1742-6596/1815/1/012040

Abstract:
UAV (Unmanned Aerial Vehicle) application is becoming wider and wider, its flight safety and performance is quite important. As one of its key components, EMA (Electronic Mechanical Actuator) plays a significant role in deciding UAV performance. In order to reduce cost, shorten design period and save human power, a novel way to realize standardization of the EMA controller is presented in this paper. Based on analysis of the typical EMA with DC (Direct Current) brush motor as its power source used in UAV, the standardization controller is designed. The generalized hardware platform is built with all the functional parts required. And then the communication protocol is made for EMA controller configuration. The upper computer software and the embedded software collaborates to conduct various controller functions. The standardization controller features modularization, combination and seriation, which is better than the traditional EMA controller for it saves cost and time. Several ground tests and flight tests prove its feasibility and validity.
Cheng Liu, Yaoheng Yang, Weibao Qiu, Yan Chen, Jiyan Dai,
Published: 1 February 2021
Ultrasonics, Volume 110; doi:10.1016/j.ultras.2020.106289

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Mahmoud Adel, , Ashraf A. Mohamed
Journal of Physics and Chemistry of Solids, Volume 149; doi:10.1016/j.jpcs.2020.109760

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, V. Bykov, I. Pagani, F. Lucca, L. Wegener, H-S. Bosch
Published: 1 February 2021
Fusion Engineering and Design, Volume 163; doi:10.1016/j.fusengdes.2020.112136

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, Ana C. Tavares, Enrico Traversa
Published: 27 January 2021
Frontiers in Chemistry, Volume 8; doi:10.3389/fchem.2020.641129

Abstract:
Editorial on the Research Topic Chemistry, a Sustainable Bridge From Waste to Materials for Energy and Environment The recent acceleration of climate changes and associated catastrophic phenomena worldwide is calling for unprecedented efforts for protecting our environment. The United Nations Sustainable Development Goals (SDGs) are now playing a major role in the policies of many governments. One of the main tools for reaching sustainability is adopting the concept of circular economy. We cannot afford anymore the unlimited growth of waste as in the linear economy model, but we should go toward reusing and recycling of commodities at their end of life cycle. In this framework, the transition to sustainability needs new sustainable approaches in chemical synthesis, since chemistry has a predominant role in the production of new materials. The present research topic focuses on the possibility to use waste-derived precursors for preparing new materials (Figure 1) for environmental remediation or for sustainable energy applications. The general idea is based on the sustainability concepts, which consider both the limitation of a damage and the creation of a benefit. Thus, the use of waste, which needs to be eliminated, often at some cost, could be seen as a damage limitation. The production of materials from waste-precursors is considered benefic for the society and economy. If the material is used for environmental and energy applications, benefit is further increased, and damage is further limited. FIGURE 1. In this Research Topic, Chemistry is presented as a bridge connecting waste to materials, that can be further used for a greener and sustainable world. The majority of the research work in this field still concerns organic waste, which can be transformed into carbon-based materials to be used in the formulation of heterogeneous catalysts and electrochemical double-layer capacitors or as pollutant absorbents. For example, the lignin fraction of the pitch pine sawdust was extracted and transformed into a porous biochar containing graphitic carbon through a two-step activation process. The waste derived carbon was used as adsorbent for the removal of wastewater pharmaceutical pollutants, through an absorption mechanism that changes with pH (Tam et al.). Bagasse and cluster stalks from winemaking waste were transformed into microporous-mesoporous carbon structures through a hydrothermal process followed by alkaline activation. These materials display high electrochemical double-layer capacitance and stability and can be considered for application as negative electrodes in electrochemical energy storage devices (Alcaraz et al.). A detailed knowledge on the physical-chemical and catalytic properties of activated carbons derived from commercial glycerol and of their interaction with reaction reagents and solvents gives an important contribute to the use of biomass derived carbons to produce platform molecules (Tudino et al.). New materials can be obtained from specific waste-derived precursors, taking advantage of the specific waste features, usually related to the chemical composition of the waste precursor or to its microstructure/morphology. For example, Magnacca et al. evidenced some peculiar properties of porous alumina membranes prepared from bio-based substances from compost, resulting in a selective adsorption of cationic species. In their perspective article, Fiorani et al. describe the chemical complexity of plant-based biomasses, pointing out to the urgency of reliable and convergent chemical strategies for their transformation into platform molecules. As reported by Tummino et al., soybean hulls from agro-industrial scraps can be still used after peroxidase extraction as adsorbents for inorganic and organic pollutants present in wastewater. The authors also evidenced that the adsorption efficiency is strongly dependent on the extraction conditions. There are plenty opportunities for research work on the chemical synthesis of materials derived from inorganic waste. Therefore, we encourage the scientific community to intensify the research in this specific field, being convinced that any advancement of knowledge in this direction may also have a considerable impact on society. It is enough to consider for example the electric/electronic waste, the waste tires, wastewater, sludges and other types of inorganic industrial waste that are at the moment seldom recycled. Abdelbasir et al. report here a strategy to transform inorganic waste into inorganic nanoparticles for use in environmental applications. However, toxicological and life-cycle aspects should be taken into consideration for upscaling the synthesis process (Abdelbasir et al.). Another strategy is the extraction of metal cations from industrial inorganic waste and their use as inorganic precursors for the synthesis of materials, as described by Tamas et al. for Zn ash used as a Zn precursor. A further step will be to use the inorganic waste directly in the synthesis without any acid/base extraction. Finally, we would like to thank all authors and reviewers who contributed to this Research Topic. The papers collection under this Research Topic gave a substantial contribution to the knowledge on the use of waste-derived precursors in the synthesis of materials for energy and environmental applications. In the next future, new synthesis procedures need to be explored and greater flexibility will be required to maximize the economic and technological advantages of waste-derived materials production. In this sense, the role of Chemistry as “a sustainable bridge from waste to materials for energy and environment” needs to be further consolidated, in order to facilitate the transition from ideas to real industrial-social opportunities. FD wrote the first draft, ET and AT corrected and integrated it. The authors declare that the research was conducted in the absence of any commercial or financial relationships that...
, Andriy Zaborovsky, Pawel Bloniarz, Tomasz Paczeŝniak, Dariya Maksym, Jacques Muzart
Reaction Kinetics, Mechanisms and Catalysis, Volume 132, pp 123-137; doi:10.1007/s11144-020-01913-6

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Ernest Sergeevich Karpov, Murzina Olga Viktorovna
Published: 21 January 2021
KnE Social Sciences pp 409–417-409–417; doi:10.18502/kss.v5i2.8384

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IEEE Transactions on Electron Devices, Volume 68, pp 2003-2009; doi:10.1109/ted.2021.3049455

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Published: 1 January 2021
Optics Communications, Volume 478; doi:10.1016/j.optcom.2020.126395

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Nadezhda Zhuk, Nikolay Sekushin, Boris Makeev
Letters on Materials, Volume 11, pp 11-16; doi:10.22226/2410-3535-2021-1-11-16

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, I-Ping Hsiao, Fong-Yi Chang, Cheng-Liang Hsu
Materials Science in Semiconductor Processing, Volume 121; doi:10.1016/j.mssp.2020.105295

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ACS Applied Materials & Interfaces, Volume 13, pp 1651-1661; doi:10.1021/acsami.0c20443

Abstract:
A novel green protocol for the consolidation and protection of waterlogged archeological woods with wax microparticles has been designed. First, we focused on the development of halloysite nanotubes (HNTs) based Pickering emulsions using wax as the inner phase of the oil-in-water droplets. The optimization of the preparation strategy was supported by both optical microscopy and scanning electron microscopy, which allowed us to show the morphological features of the prepared hybrid systems and their structural properties, i.e., the distribution of the clay at the interface. Also, the dependence of the overall dimensions of the prepared systems on the halloysite content was demonstrated. Microdifferential scanning calorimetry (μ-DSC) was conducted in order to assess whether the thermal properties of the wax are affected after its interaction with HNTs. Then, the Pickering emulsions were employed for the treatment of waterlogged wooden samples. Compared to the archeological woods treated with pure wax, the addition of nanotubes induced a remarkable improvement in the mechanical performance in terms of stiffness and flexural strength. The proposed protocol is environmentally friendly since water is the only solvent used throughout the entire procedure, even if wax is vehiculated into the pores at room temperature. As a consequence, the design of wax/halloysite Pickering emulsions represents a promising strategy for the preservation of wooden artworks, and it has a great potential to be scaled up, thus becoming also exploitable for the treatments of shipwrecks of large size.
Lucía Hortal, Cristina Pérez-Fernández, José L. De La Fuente, Pilar Valles, Eva Mateo-Martí,
Scientific Reports, Volume 10, pp 1-14; doi:10.1038/s41598-020-79112-5

Abstract:
In this paper, the first study on NH4CN polymerization induced by microwave radiation is described, where a singular kinetic behaviour, especially when this reaction is conducted in the absence of air, is found. As a result, a complex conjugated N-heterocyclic polymer system is obtained, whose properties are very different, and even improved according to morphological features, characterized by their X-ray diffraction patterns and scanning electron microscopy analysis, with respect to those produced under conventional thermal treatment. In addition, a wide variety of relevant bioorganics have been identified, such as amino acids, nucleobases, co-factors, etc., from the synthetized NH4CN polymers. These particular families of polymers are of high interest in the fields of astrobiology and prebiotic chemistry and, more recently, in the development of smart multifunctional materials. From an astrobiological perspective, microwave-driven syntheses may simulate hydrothermal environments, which are considered ideal niches for increasing organic molecular complexity, and eventually as scenarios for an origin of life. From an industrial point of view and for potential applications, a microwave irradiation process leads to a notable decrease in the reaction times, and tune the properties of these new series macromolecular systems. The characteristics found for these materials encourage the development of further systematic research on this alternative HCN polymerization.
Huachuan Wang, Yuanfei Bi
Published: 11 December 2020
by ArXiv
Abstract:
Mortality prediction in intensive care units is considered one of the critical steps for efficiently treating patients in serious condition. As a result, various prediction models have been developed to address this problem based on modern electronic healthcare records. However, it becomes increasingly challenging to model such tasks as time series variables because some laboratory test results such as heart rate and blood pressure are sampled with inconsistent time frequencies. In this paper, we propose several deep learning models using the same features as the SAPS II score. To derive insight into the proposed model performance. Several experiments have been conducted based on the well known clinical dataset Medical Information Mart for Intensive Care III. The prediction results demonstrate the proposed model's capability in terms of precision, recall, F1 score, and area under the receiver operating characteristic curve.
Ahmad Nizamuddin, Faiz Arith, Ing Jia Rong, Muhammad Zaimi, A Shamsul Rahimi, Shahrizal Saat
Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, Volume 78, pp 153-159; doi:10.37934/arfmts.78.2.153159

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Weiwei Liu, Jing Liu, Menghua Zhu, Wenyu Wang, Lei Wang, , , ,
ACS Applied Materials & Interfaces, Volume 12, pp 57055-57063; doi:10.1021/acsami.0c16865

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Zhiyong Wang, Laiyuan Wang, Yiming Wu, Linyi Bian, Masaru Nagai, Ruolin Jv, , Hai-Feng Ling, Qi Li, Hongyu Bian, et al.
Published: 2 December 2020
Abstract:
By threshold-regulated neural firing and synaptic weight updates in biological neuron–synapse combinations, neural systems can selectively and autonomously encode and process spatiotemporal information. Emulating such an exquisite biological process in electronic devices is a fundamental step toward realizing intelligent neuromorphic systems with self-adaptivity, energy-efficient in-situ edge/parallel computing, and probabilistic inference. Here we report a self-threshold design of prototype artificial axons based on metalloporphyrin, a molecular medium that allows dual electronic/ionic migration in hybrid heterojunction oxide memristors. Threshold behaviors in biological neurons are emulated by introducing metalloporphyrin into alumina-oxide memristors. We show that the memristor achieves smooth, gradual conductive transitions. As a unique feature of such a hybrid system, the endurable current-voltage characteristics of the memristor can be enhanced by altering the metal center to achieve the desired metal–oxygen bonding energy and oxygen migration dynamics. The spike voltage-dependent plasticity is recorded with a positive threshold voltage stemming from the interfacial counterbalance between the vacancy-induced Coulomb force and the external electric field. We further build memristive arrays that directly emulate the self-adaptive and signal-filtering function of the human visual system. These results suggest that the metalloporphyrin platform offers vast opportunities for implementing efficient neural-signal analysis in neuromorphic hardware.
Shaghayegh Saadati, Heloisa Westphalen, Ubong Eduok, , Ahmed Shoker, Phillip Choi, Huu Doan, Farhad Ein-Mozaffari, Ning Zhu
Published: 1 December 2020
Materials Science and Engineering: C, Volume 117; doi:10.1016/j.msec.2020.111301

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Weijun Li, Hao Liu, Yuanyuan Mi, Miaoran Zhang, JinMiao Shi, Ming Zhao, Melvin A. Ramos, Travis Shihao Hu, Jianxiong Li, Meng Xu, et al.
Published: 1 December 2020
Friction pp 1-14; doi:10.1007/s40544-020-0416-x

Abstract:
There is a high demand for hydrogels with multifunctional performance (a combination of adhesive, mechanical, and electrical properties) in biological, tissue engineering, robotics, and smart device applications. However, a majority of existing hydrogels are relatively rigid and brittle, with limited stretchability; this hinders their application in the emerging field of flexible devices. In this study, cheap and abundant potato residues were used with polyacrylamide (PAM) to fabricate a multifunctional hydrogel, and chitosan was used for the design of a three-dimentional (3D) network-structured hydrogel. The as-prepared hydrogels exhibited excellent stretchability, with an extension exceeding 900% and a recovery degree of over 99%. Due to the combination of physical and chemical cross-linking properties and the introduction of dopamine, the designed hydrogel exhibits a remarkable self-healing ability (80% mechanical recovery in 2 h), high tensile strength (0.75 MPa), and ultra-stretchability (900%). The resultant products offer superior properties compared to those of previously reported tough and self-healing hydrogels for wound adhesion. Chitosan and potato residues were used as scaffold materials for the hydrogels with excellent mechanical properties. In addition, in vitro experiments show that these hydrogels feature excellent antibacterial properties, effectively hindering the reproduction of bacteria. Moreover, the ternary hydrogel can act as a strain sensor with high sensitivity and a gauge factor of 1.6. The proposed strategy is expected to serve as a reference for the development of green and recyclable conductive polymers to fabricate hydrogels. The proposed hydrogel can also act as a suitable strain sensor for bio-friendly devices such as smart wearable electronic devices and/or for health monitoring.
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