bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of the effect of water absorption on thermomechanical and viscoelastic properties of flax‐hemp‐reinforced hybrid composite
Authors: Saha Abir , Kumar Santosh , Zindani Divya
Published: June 2021

The recent development of natural fiber‐reinforced polymer composites have shown innumerable economic and environmental benefits for a vast array of engineering applications. It is quintessential to investigate the effect of water absorption on the composites that remain in the water for a maximum of their intended service period. This study is an effort in this direction that investigates the effect of water absorption on thermo‐mechanical properties of flax‐hemp‐reinforced epoxy composites fabricated using compression hand layup technique with different weight fraction of fiber. The fabricated composites have been characterized physically (density and water absorption), thermo‐mechanically (tensile, flexural, thermal conductivity, and dynamical mechanical analysis), and morphologically (scanning electron microscopy [SEM]). The analysis revealed that hemp‐reinforced composites (S1) had the highest water absorption capabilities in comparison to the flax‐reinforced composites (S5). Higher water absorption capability had an adverse effect on the mechanical properties of fabricated composites. However, hybrid composites (S2, S3, and S4) reported better performance with regard to S1. The increased water content, however, increased the thermal conductivity of composites and maximum has been revealed for S1 (0.82 W/mK) and minimum for S5 (0.48 W/mK). The water molecules showed detrimental effects on the viscoelastic properties and revealed S3 have better interlocking bond with the lowest reduction in storage modulus (12%) and glass transition temperature (4°C) in comparison to S1 (30%) under wet conditions. A comparative analysis of the thermo‐mechanical properties was also made for developed composites under dry, saturated, and re‐dried conditions. The SEM has been used to characterize the morphological and fracture behavior of the fabricated composites under the influence of water uptake. The effects of water molecules on the hygrothermal aging index and diffusion co‐efficient have also been discussed. Overall, the hybridization of flax with hemp fiber showed better results over the hemp fiber‐reinforced composites (S1).
Mechanical performance of a novel environmentally friendly basalt‐elium® thermoplastic composite and its stainless steel‐based fiber metal laminate
Authors: Yaghoobi Hessameddin , Taheri Farid
Published: June 2021

A comparative performance study is conducted to better understand the mechanical performance of an environmentally friendly composite and its fiber‐metal laminate (FML) renditions developed with natural fibers (basalt), and a novel room‐cured liquid methyl methacrylate thermoplastic resin (Elium®) and also by a widely used room‐cured epoxy resin (West System). Mechanical characterizations are performed using tensile, buckling and flexural tests. The results indicate that the composites fabricated with the acrylic‐based Elium matrix could be considered as effective alternatives to those produced by thermoset epoxy resins. Moreover, the mechanical properties of a new generation of thermoplastic fiber metal laminates (TP‐FMLs) fabricated by vacuum‐assisted resin infusion technique are also investigated. The TP‐FMLs are fabricated using stainless steel sheets, basalt fabric and Elium. Two different procedures are considered for fabricating the TP‐FMLs; a one‐step process consuming 24 h curing cycle time and a two‐step process with 72 h curing cycle time. The mechanical responses of the developed TP‐FMLs are compared against their equivalent monolithic environmentally friendly basalt‐Elium counterparts, demonstrating the gain in mechanical responses that could be attained by employing the TP‐FMLs.
Polypharmacy and the risk of drug–drug interactions and potentially inappropriate medications in hospital psychiatry
Authors: Wolff Jan , Hefner Gudrun , Normann Claus , Kaier Klaus , Binder Harald , Hiemke Christoph , Toto Sermin , Domschke Katharina , Marschollek Michael , Klimke Ansgar
Published: June 2021

Purpose

The aim of this study was to analyze the epidemiology of polypharmacy in hospital psychiatry. Another aim was to investigate predictors of the number of drugs taken and the associated risks of drug–drug interactions and potentially inappropriate medications in the elderly.

Methods

Daily prescription data were obtained from a pharmacovigilance project sponsored by the Innovations Funds of the German Federal Joint Committee.

Results

The study included 47 071 inpatient hospital cases from eight different study centers. The mean number of different drugs during the entire stay was 6.1 (psychotropic drugs = 2.7; others = 3.4). The mean number of drugs per day was 3.8 (psychotropic drugs = 1.6; others = 2.2). One third of cases received at least five different drugs per day on average during their hospital stay (polypharmacy). Fifty‐one percent of patients received more than one psychotropic drug simultaneously. Hospital cases with polypharmacy were 18 years older (p < 0.001), more likely to be female (52% vs. 40%,p < 0.001) and had more comorbidities (5 vs. 2,p < 0.001) than hospital cases without polypharmacy. The risks of drug–drug interactions (OR = 3.7; 95% CI = 3.5–3.9) and potentially inappropriate medication use in the elderly (OR = 2.2; CI = 1.9–2.5) substantially increased in patients that received polypharmacy.

Conclusion

Polypharmacy is frequent in clinical care. The number of used drugs is a proven risk factor of adverse drug reactions due to drug–drug interactions and potentially inappropriate medication use in the elderly. The potential interactions and the specific pharmacokinetics and ‐dynamics of older patients should always be considered when multiple drugs are used.
Lab‐scale feasibility study on new elastomer comprising chloroprene and acrylonitrile for oil and gas applications
Authors: De Sarkar Mousumi , Sunada Takashi , Kondo Atsunori
Published: June 2021

The limited options of suitable elastomers with adequate cost‐performance balance drive the necessity to introduce new materials in the oil & gas (O&G) application space. The relevance of a recently developed copolymer of chloroprene and acrylonitrile (referred to as acrylonitrile–chloroprene rubber or NCR) to O&G applications is described in this technical contribution. The new elastomer demonstrates adequate physical properties and reasonably good high and low‐temperature capabilities. It offers good resistance to several aqueous and non‐aqueous fluids with low volume swelling and retains its physical properties to reasonable extents while exposed to hot test oils. Acrylonitrile–chloroprene rubber has been found to sustain “sour gas” exposure. Good abrasion resistance, high tear strength, and remarkably high flex‐fatigue resistance coupled with low heat build‐up reflect its durability under dynamic conditions. In addition, acrylonitrile–chloroprene rubber can very well withstand the rapid gas decompression test at 25°C. This unique combination of attributes may allow acrylonitrile–chloroprene rubber to be considered as a candidate material for high‐performance O&G applications.
Bottom‐up and top‐down proteomic approaches for the identification, characterization, and quantification of the low molecular weight proteome with focus on short open reading frame‐encoded peptides
Authors: Cassidy Liam , Kaulich Philipp T. , Maaß Sandra , Bartel Jürgen , Becher Dörte , Tholey Andreas
Published: June 2021

The recent discovery of alternative open reading frames creates a need for suitable analytical approaches to verify their translation and to characterize the corresponding gene products at the molecular level. As the analysis of small proteins within a background proteome by means of classical bottom‐up proteomics is challenging, method development for the analysis of small open reading frame encoded peptides (SEPs) have become a focal point for research. Here, we highlight bottom‐up and top‐down proteomics approaches established for the analysis of SEPs in both pro‐ and eukaryotes. Major steps of analysis, including sample preparation and (small) proteome isolation, separation and mass spectrometry, data interpretation and quality control, quantification, the analysis of post‐translational modifications, and exploration of functional aspects of the SEPs by means of proteomics technologies are described. These methods do not exclusively cover the analytics of SEPs but simultaneously include the low molecular weight proteome, and moreover, can also be used for the proteome‐wide analysis of proteolytic processing events.
Absorption and fluorescence spectra of conjugated polymers poly(propylene oxide)–poly(phenylene ethynylene) interpreted by Franck–Condon simulation
Authors: Tang Hao , Wang Chen Wen , Gu Feng Long , Zhu Chaoyuan
Published: June 2021

Absorption and fluorescence spectra of the poly(propyleneoxide)–poly(phenylene ethynylene) with long polymer chains in the experiment are investigated by the Franck–Condon simulation with small polymer chains in the theory. Electronic calculations with time‐dependent density functional (TDDFT) indicate that vibronic spectra come from S1(ππ*) excitation and de‐excitation. Good agreement between Franck–Condon simulated and experimentally measured absorption and fluorescence spectra in three kinds of solutions is achieved. However, vibronic spectral analysis reveals that vibronic motion mechanisms are quite different for simulated absorption and fluorescence spectra. For absorption spectra, vibronic spectra are dominated by one most active mode localized in triple bond carbon–carbon stretch motion on backbone of the poly (phenylene ethynylene), and simulated absorption spectra indicate that the long chains can be as stable as short chains on the electronic ground state in comparison with experimental spectra in all solvents. In the case of fluorescence spectra, this most active mode is spitting into several equally active modes with very close values in vibrational frequencies, and thus, the spitting modes and mode couplings among those spitting dominate vibronic spectra. Simulated fluorescence spectra indicate that the only short chains are stable on the electronic excited state in comparison with experimental spectra in all solvents. Nevertheless, the present simulation concludes that both absorption and fluorescence spectra are induced mostly by the active normal mode in triple bond carbon–carbon stretch motion on backbone of poly(phenylene ethynylene). The present work provides physical insight for analyzing observed vibronic spectra of similar conjugated polymers and for designing novel optoelectronic materials.
Improvement of the adhesive capacity of SBR for footwear outsoles by surface activation and coating deposition with atmospheric pressure plasma
Authors: Múgica‐Vidal Rodolfo , Mercadal‐Guillén Juan , Alba‐Elías Fernando , Sainz‐García Elisa
Published: June 2021

Looking for a cleaner alternative to halogenation in the preparation of rubber for bonding with leather in footwear, atmospheric pressure plasma treatments were applied on styrene–butadiene rubber (SBR). Its adhesive capacity was improved and the highest bond strength standards for footwear were met. Two optimal processes were identified: (1) Plasma polymerization of (3‐aminopropyl)triethoxysilane coatings on flat SBR and (2) plasma‐activation of mechanically roughened SBR. The improvement on coated, flat SBR was mainly due to its surface chemistry having greater concentrations of polar carbon–oxygen species than the untreated SBR. For plasma‐activated, mechanically roughened SBR, combined contributions of mechanical roughening and roughening by plasma irradiation were found. Coating flat SBR at 100 mm/s showed the best balance between improved bond strength and durability.
In Situ Self‐Assembly of Quantum Dots at the Plasma Membrane Mediates Energy Transfer‐Based Activation of Channelrhodopsin
Authors: Nag Okhil K. , Muroski Megan E. , Field Lauren D. , Stewart Michael H. , Oh Eunkeu , Susumu Kimihiro , Spangler Joseph R. , Walper Scott A. , Delehanty James B.
Published: June 2021

The use of nanoparticle (NP) bioconjugates to control the activity of membrane ion channels has recently emerged as a new paradigm for the activation of electrically excitable cells. An NP‐based strategy is reported for the specific activation of channelrhodopsin C1V1 (ChR‐C1V1) expressed in the plasma membrane of HEK 293T/17 cells. Hydrophilic CdSe/ZnS core–shell semiconductor quantum dots (QDs) are self‐assembled to the exofacial face of recombinantly expressed ChR‐C1V1 by metal affinity‐driven interaction of the QD ZnS shell with an N‐terminal hexahistidine tag displayed on ChR‐C1V1. This configuration enables the Förster resonance energy transfer (FRET)‐based excitation and activation of the 11‐cis‐retinal moiety of ChR‐C1V1 using the QD as a light harvesting transducer/energy donor. It is shown that the specific laser‐induced opening of the ChR‐C1V1 channel wherein the photoexcited QD (405 nm excitation, 530 nm emission) iteratively activates ChR‐C1V1 channels as confirmed using the voltage‐sensitive dye (VSD) bis‐(1,3‐diethylthiobarbituric acid)trimethine oxonol (DiSBAC2(3)). In the absence of the QD transducer, excitation of ChR‐C1V1‐expressing cells at 405 nm results in no activation of ChR‐C1V1. The results demonstrate the ability to controllably interface QDs with living cells for the activation of ChR membrane proteins and detail a new NP‐bioconjugate hybrid system for the specific activation of ion channels.
Potential inoculum sources of Fusarium species involved in asparagus decline syndrome and evaluation of soil disinfestation methods by qPCR protocols
Authors: de la Lastra Eduardo , Marín‐Guirao José I , López‐Moreno Francisco J , Soriano Teresa , de Cara‐García Miguel , Capote Nieves
Published: June 2021

BACKGROUND

Asparagus decline syndrome (ADS), one of the most important diseases affecting asparagus crops, causes important yield losses worldwide. Fusarium proliferatum, F. oxysporum and F. redolens are among the main species associated with ADS. To explore their potential inoculum sources and the effectiveness of soil disinfestation practices for ADS management, molecular methods based on a quantitative real‐time polymerase chain reaction (qPCR) were developed. qPCR‐based molecular tools demonstrated advantages in the sensitive and specific detection and quantification of fungal pathogens in comparison with less‐accurate and time‐consuming traditional culture methods.

RESULTS

F. proliferatum, F. oxysporum and F. redolens could be specifically detected and accurately quantified in asparagus plants, soil and irrigation water collected from asparagus fields with ADS symptoms by means of the designed TaqMan qPCR protocols. Furthermore, these molecular tools were successfully applied for evaluation of the efficacy of diverse soil disinfestation treatments. Chemical fumigation with dazomet and biosolarization with pellets of Brassica carinata contributed to a significant reduction in the inoculum densities of the three Fusarium species in treated soils, which was correlated with production increases.

CONCLUSIONS

The capability to accurately detect and quantify the main Fusarium species involved in ADS in plants, soil and water samples by means of qPCR will allow identification of high‐risk fields that can be avoided or managed to reduce yield losses. Quantification of pathogen densities in the soil may also provide essential insights into the effectiveness of soil disinfestation methods for ADS management. © 2021 Society of Chemical Industry.
Tunable Asymmetric Transmissions via Anisotropic Acoustic Metamaterials
Authors: Zhang Zheng , Bai Lin , Xu Liang , Jiang Wei Xiang , Cui Tie Jun
Published: June 2021

An acoustic prism for asymmetric transmissions is proposed, designed, and fabricated by an anisotropic metamaterial composed of an array of controllable C‐shaped meta‐atoms. Due to the anisotropic configuration of the meta‐atom, the effective refractive index of the prism can be continuously tuned by rotating the meta‐atom. It is demonstrated that the transmitted wave direction of an incident acoustic wave from one direction can be controlled in real time, as the rotation angle of meta‐atom changes gradually. Meanwhile, the incident acoustic wave from the opposite direction will be blocked all the time. Furthermore, a wide range of transmitted angles can be obtained by reshaping the prism, which can work in a broadband (4400–5200 Hz). The results are verified through theoretical predictions, numerical simulations, and experimental measurements. The method can be extended to realize other kinds of tunable asymmetric transmissions of waves via anisotropic metamaterials with controllable meta‐atoms.
Recent Progress in Selector and Self‐Rectifying Devices for Resistive Random‐Access Memory Application
Authors: Dongale Tukaram D. , Kamble Girish U. , Kang Dae Yun , Kundale Somnath S. , An Ho-Myoung , Kim Tae Geun
Published: June 2021

The recent progress of selector and self‐rectifying devices for resistive random‐access memory applications is reviewed. In particular, the performance of crossbar arrays based on resistive switching (RS) devices, the sneak‐path current issue, and possible solutions is discussed. The parameters and requirements of selector devices are elucidated here, and several types of selector devices, such as a transistor‐assisted transistor‐one resistor, unipolar one diode‐one resistor, bipolar one selector‐one resistor, and threshold switching selectors, are comprehensively discussed. In the case of self‐rectifying devices, the recent progress in complementary RS devices, vacancy‐modulated conductive oxide‐based devices, and tunneling barrier‐based RS devices is reviewed. The switching mechanisms and the geometrical configuration of the selector and self‐rectifying RS devices are emphasized. Furthermore, comparative assessments of the different devices are evaluated. Finally, an overview of the gaps in previously reported devices is presented and some key improvements for future research direction suggested.
Enhancement of Spin Pumping from CoFeB to Sb2Te3 Layers by Crystal Orientation Control
Authors: Morota Misako , Saito Yuta , Uchida Noriyuki
Published: June 2021

Sb2Te3 is well known as a phase‐change material, and is expected to exhibit high spin–charge current conversion because of its strong spin–orbit interactions. Reversible phase‐change characteristics enable manipulation of physical properties depending on phase. Therefore, it is anticipated that its spin properties can also be tuned by controlling the phases of Sb2Te3, promising great potential for novel spintronic devices. However, the effects of crystallinity on the spin properties of Sb2Te3 have not yet been investigated. Herein, the spin relaxation induced by the spin‐pumping effect in CoFeB/Sb2Te3 bilayers is examined using ferromagnetic resonance (FMR) at 300 K for crystalline and amorphous Sb2Te3. FMR signal width enhancement is observed for the highly oriented crystalline Sb2Te3 film at thickness less than 7 nm. In contrast, the FMR signal widths of the amorphous sample are independent of the layer thickness. The significant increase in linewidth suggests more efficient spin injection from the ferromagnetic CoFeB layer into crystalline Sb2Te3 than into amorphous Sb2Te3. This stark contrast between the spin dynamics of the amorphous and crystalline Sb2Te3 films supports the idea that spin conduction can be tuned by controlling the crystal orientation of Sb2Te3 films.
Observation of the Out‐of‐Plane Polarized Spin Current from CVD Grown WTe2
Authors: Shi Shuyuan , Li Jie , Hsu Chuang‐Han , Lee Kyusup , Wang Yi , Yang Li , Wang Junyong , Wang Qisheng , Wu Hao , Zhang Wenfeng , Eda Goki , Liang Gengchiau , Chang Haixin , Yang Hyunsoo
Published: June 2021

Weyl semimetal Td‐phase WTe2 possesses the spin‐resolved band structure with strong spin–orbit coupling, holding promises as a useful spin source material. The noncentrosymmetric crystalline structure of Td‐WTe2 endows the generation of the out‐of‐plane polarized spin, which is of great interest in magnetic memory applications. Previously, WTe2 was explored in spin devices based on mechanically exfoliated single crystal flakes with a size of micrometers. For practical spintronics applications, it is highly desirable to implement wafer‐scale thin films. In this work, centimeter‐scale chemical vapor deposition (CVD) grown Td‐WTe2 thin films are used and the spin current generation is studied by the spin torque ferromagnetic resonance (ST‐FMR) technique. The in‐plane and out‐of‐plane spin conductivities of 7.36 × 103 () (Ωm)–1 and 1.76 × 103 () (Ωm)–1, respectively, are found in CVD‐growth 5 nm‐WTe2. The current‐induced magnetization switching in WTe2/NiFe is demonstrated at room temperature in the domain wall motion regime, which may invigorate potential spintronic device innovations based on Weyl semimetals.
Waste from Argentometric Determination of Chloride as a Source of Silver in the Synthesis of p‐Hydroxybenzoic Acid Capped Silver Nanoparticles
Authors: Gusrizal Gusrizal , Zaharah Titin Anita , Shofiyani Anis , Santosa Sri Juari
Published: June 2021

This paper describes the utilization of waste from the argentometric determination of chloride in a chemistry teaching laboratory as a source of silver for the synthesis of p‐hydroxybenzoic acid capped silver nanoparticles (AgNPs). All white and red‐brick precipitates in the waste were first separated from the liquid and converted to silver chloride precipitate by washing the precipitates using hydrochloride acid 0.1 M. The silver chloride precipitate was then converted to diammineargentate complex ion by dissolving it into an ammonia solution. The conversion was successfully conducted by using 50 moles of ammonia for every mole of silver chloride. The formation of AgNPs was optimum by applying diammineargentate complex ion and p‐hydroxybenzoic acid solutions at a molar ratio of 1 : 10. The formed AgNPs showed a yellow color and absorption peak at around 420 nm with an average particle size of 26.4 nm. The as‐synthesized AgNPs were stable at least 16 weeks of storage, indicating that p‐hydroxybenzoic acid did not only act as a reducing agent but also play a role as a capping agent.
One‐Pot Solvothermal Synthesis of Flower‐Like S‐Doped BiOCl for Enhanced Photocatalytic Property in Dye Degradation and Nitrogen Fixation
Authors: Wang Hongjuan , Hua Chenghe , Lan Meng , Zheng Nan , Dong Xiaoli , Ma Hongchao , Zhang Xiufang
Published: June 2021

Nowadays, environmental pollution and energy shortage have aroused people‘s wide concern. Here we report that S‐doped BiOCl photocatalyst was successfully fabricated via a simple solvothermal process. The as‐obtained S‐doped BiOCl photocatalysts were investigated by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray photoemission spectroscopy (XPS), nitrogen adsorption‐desorption, UV/Vis diffuse reflectance (DRS), and photoluminescence (PL) emission spectra. The photocatalytic performance of the S‐doped BiOCl photocatalyst with different S contents was evaluated by the photocatalytic degradation of cationic dye (Rhodamine‐B (RhB)) and anionic dye (Congo red (CR)). The results reveal that all the S‐doped BiOCl samples possess better photocatalytic activity than pure BiOCl. Specifically, the degradation rate of S(6 %)‐BiOCl sample for RhB and CR was 99 % and 90 %, respectively. Meanwhile, the photocatalytic nitrogen fixation performance of the S‐doped BiOCl sample was investigated. The results show that the S(6 %)‐BiOCl sample possesses an excellent NH3 yield of 108.6 μmol g−1 h−1. Moreover, the S(6 %)‐BiOCl catalysts have excellent recyclability and stability. This work provides a facile and accessible pathway to design effective photocatalysts for both photocatalytic degradation and nitrogen fixation.
Identification of SARS‐CoV‐2 Main Protease Inhibitors Using Structure Based Virtual Screening and Molecular Dynamics Simulation of DrugBank Database
Authors: Debnath Pradip , Bhaumik Samhita , Sen Debanjan , Muttineni Ravi K. , Debnath Sudhan
Published: June 2021

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) is highly pathogenic to humans and has created an unprecedented global health care threat. Globally, intense efforts are going on to discover a vaccine or new drug molecules to control the COVID‐19. However, till today, there is no effective therapeutics or treatment available for COVID‐19. In this study, we aim to find out potential small molecule inhibitors for SARS‐CoV‐2 main protease (Mpro) from the known DrugBank database version 5.1.8. We applied structure‐based virtual screening of the database containing 11875 numbers of drug candidates to identify potential hits for SARS‐CoV‐2 Mpro inhibitors. Seven potential inhibitors having admirable XP glide score ranging from −15.071 to −8.704 kcal/mol and good binding affinity with the active sites amino acids of Mpro were identified. The selected hits were further analyzed with 50 ns molecular dynamics (MD) simulation to examine the stability of protein‐ligand complexes. The root mean square deviation and potential energy plot indicates the stability of the complexes during the 50 ns MD simulation. The MM‐GBSA analysis also showed good binding energy of the selected hits (−83.2718 to −58.6618 kcal/mol). Further analysis revealed critical hydrogen bonds and hydrophobic interactions between compounds and the target protein. The compounds bind to biologically important regions of Mpro, indicating their potential to inhibit the functionality of this component.
Synthesis, DFT Study, Molecular Docking and Drug‐Likeness Analysis of the New Hydrazine‐1‐Carbothioamide, Triazole and Thiadiazole Derivatives: Potential Inhibitors of HSP90
Authors: Çapan İrfan , Servi Süleyman , Yıldırım İsmail , Sert Yusuf
Published: June 2021

In this research, the new hydrazine‐1‐carbothioamides (IC32 and IC34) having unsubstituted benzimidazole skeleton were converted to 1, 2, 4‐triazole derivatives (IC42 and IC44) by N‐cyclization reaction using the microwave‐assisted synthesis method in the basic medium with high efficiency in a short time. 2‐Amino‐1,3,4‐thiadiazole derivatives (IC52 and IC54) were obtained from the carbothioamides in the acidic medium by S‐cyclization using the conventional method. The structure of all compounds was confirmed by FT‐IR, 1H NMR, and 13C NMR spectroscopic techniques. The optimized structures, theoretical NMR shielding values in DMSO‐d6 solvent, the frontier molecular orbital, molecular electrostatic potential, and non‐linear optical properties of these molecules were calculated in the Gaussian 09 W package program by using DFT method/B3LYP function and 6‐311++G (d, p) basis set. All calculations except NMR calculations were performed in the gas phase and the obtained results were interpreted within the related sections. The discovery of new drugs is of great importance in combating health problems and improving the quality of human life. In the light of this information, molecular docking with Autodock Vina and physicochemical calculations with the SwissADME server were performed at the end of the article. Therefore, the inhibiting potential of the ligands containing different groups in their structure was investigated for the first time in this study.
Synthesis, Spectroscopic, Biological Activity, Molecular Docking and Density Functional Theoretical Investigations of Novel Tellurium(IV) Schiff Base Complexes
Authors: Kumar Manish , Darolia Poonam Jangra , Chauhan Sonu , Sindhu Meena , Verma K. K. , Garg Sapana
Published: June 2021

Aryltellurium(IV) complexes (3a–3f) of type RTeCl3.NMeIAP and R2TeCl2.NMeIAP (R belongs to 4‐Hydroxyphenyl, 4‐Methoxyphenyl and 3‐Methy‐4‐hydroxyphenyl) have been synthesized from 3‐((2‐Hydroxyphenyl)imino)‐1‐methylindolin‐2‐one Schiff base ligand (NMeIAP or HL), prepared by the condensation of N‐methylisatin and o‐aminophenol in 1 : 1 molar ratio. The synthesized Schiff base and its aryltellurium(IV) complexes were characterized by molar conductance, FT‐IR, elemental analyses, SEM analyses, powder X‐ray diffraction, 1H NMR, 13C NMR, UV‐Vis, mass spectrometry, DFT studies and thermogravimetric (TG) analysis. The stoichiometry of the compounds and the percentages of the different elements present in all compounds were confirmed by the elemental analysis. The Schiff base ligand behaved as a monobasic tridentate ONO chelating agent. The molecular structures of the ligand (NMeIAP) and its complexes were optimized theoretically and their electronic properties such as HOMO and LUMO energies were determined by def2‐SVP calculations. Molecular docking studies was used to determine probable and effective binding modes between ligand and different active sites of the receptors. X‐ray diffraction revealed the crystalline nature of the Schiff base whereas the complexes are semi crystalline in nature. NMeIAP and aryltellurium(IV) complexes were tested against bacteria: B. cereus and X. campestris. Antifungal activity was determined against C. albicans, F. oxysporum and S. sclerotium.
Designing High Energy Sodium‐Ion Battery Cathodes by Utilizing P2/O3 Biphasic Structure and Lithium Honeycomb Ordering
Authors: Wang Ji Eun , Kim Heejin , Jung Young Hwa , Kim Do Kyung , Kim Dong Jun
Published: June 2021

Layered transition metal oxides, in particular P2‐type ones, are considered as promising cathode materials for sodium‐ion batteries on account of their high specific capacity and rate capability. Nevertheless, conventional layered compounds involve detrimental phase transformation throughout repeated cycles, which results in electrochemical performance degradation. Therefore, finding structurally stable layered compounds, featuring minimal phase transition has been a key theme of the sodium‐ion battery research. Here lithium substituted Fe/Mn‐based P2/O3 layered oxide—Na0.67Li0.2Fe0.2Mn0.6O2—that overcomes the inherited structural instability, is reported. In situ synchrotron‐based diffraction measurements and DFT calculations are utilized, in order to identify the association between P2/O3 biphasic structure and electrochemical performances. The lithium honeycomb ordering within the P2/O3 biphasic layered compound effectively constrains the undesirable phase transitions; more specifically, both P2‐Z phase transition and Jahn–Teller distortion are suppressed throughout wide potential range of 1.5–4.5 V. The DFT calculation further discovers that the presence of honeycomb ordering is crucial for achieving the structural stability by forming Na–vac–Li and Na–Li–Na pairing at highly charged state. The results highlight that the synergetic effect of P2/O3 biphasic structure and lithium substitution can provide an effective strategy toward achieving electrochemically stable layered cathode material for sodium‐ion batteries.
Multi‐Path Electron Transfer in 1D Double‐Shelled Sn@Mo2C/C Tubes with Enhanced Dielectric Loss for Boosting Microwave Absorption Performance
Authors: Qian Xiang , Zhang Yahui , Wu Zhengchen , Zhang Ruixian , Li Xiaohui , Wang Min , Che Renchao
Published: June 2021

1D tubular micro‐nano structural materials have been attracting extensive attention in the microwave absorption (MA) field for their anisotropy feature, outstanding impedance matching, and electromagnetic energy loss capability. Herein, unique double‐shelled Sn@Mo2C/C tubes with porous Sn inner layer and 2D Mo2C/C outer layer are successfully designed and synthesized via a dual‐template method. The composites possess favorable MA performance with an effective absorption bandwidth of 6.76 GHz and a maximum reflection loss value of −52.1 dB. Specifically, the rational and appropriate construction of Sn@Mo2C/C tubes promotes the multi‐path electron transfer in the composites to optimize the dielectric constant and consequently to enhance the capacity of electromagnetic wave energy dissipation. Three mechanisms dominate the MA process: i) the conductive loss resulted from the rapid electron transmission due to the novel 1D hollow coaxial multi‐shelled structure, especially the metallic Sn inner layer; ii) the polarization loss caused by abundant heterogeneous interfaces of Sn‐Mo2C/C and Mo2CC from the precise double‐shelled structure; iii) the capacitor‐like loss by the potential difference between Mo2C/C nanosheets. This work hereby sheds light on the design of the 1D hierarchical structure and lays out a profound insight into the MA mechanism.
Single‐Crystal MoS2 Monolayer Wafer Grown on Au (111) Film Substrates
Authors: Li Jing , Wang Shuang , Jiang Qi , Qian Haoji , Hu Shike , Kang He , Chen Chen , Zhan Xiaoyi , Yu Aobo , Zhao Sunwen , Zhang Yanhui , Chen Zhiying , Sui Yanping , Qiao Shan , Yu Guanghui , Peng Songang , Jin Zhi , Liu Xinyu
Published: June 2021

Monolayer transition metal dichalcogenides (TMDCs) with high crystalline quality are important channel materials for next‐generation electronics. Researches on TMDCs have been accelerated by the development of chemical vapor deposition (CVD). However, antiparallel domains and twin grain boundaries (GBs) usually form in CVD synthesis due to the special threefold symmetry of TMDCs lattices. The existence of GBs severely reduces the electrical and photoelectrical properties of TMDCs, thus restricting their practical applications. Herein, the epitaxial growth of single crystal MoS2 (SC‐MoS2) monolayer is reported on Au (111) film across a two‐inch c‐plane sapphire wafer by CVD. The MoS2 domains obtained on Au (111) film exhibit unidirectional alignment with zigzag edges parallel to the <110> direction of Au (111). Experimental results indicated that the unidirectional growth of MoS2 domains on Au (111) is a temperature‐guided epitaxial growth mode. The high growth temperature provides enough energy for the rotation of the MoS2 seeds to find the most favorable orientation on Au (111) to achieve a unidirectional ratio of over 99%. Moreover, the unidirectional MoS2 domains seamlessly stitched into single crystal monolayer without GBs formation. The progress achieved in this work will promote the practical applications of TMDCs in microelectronics.
A Tumor‐Penetrating Nanomedicine Improves the Chemoimmunotherapy of Pancreatic Cancer
Authors: Tong Qi‐Song , Miao Wei‐Min , Huang Hua , Luo Jia‐Qi , Liu Rong , Huang Yong‐Cong , Zhao Dong‐Kun , Shen Song , Du Jin‐Zhi , Wang Jun
Published: June 2021

Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant tumors with a low survival rate. The therapeutic effect of chemotherapy and immunotherapy for PDAC is disappointing due to the presence of dense tumor stroma and immunosuppressive cells in the tumor microenvironment (TME). Herein, a tumor‐penetrating nanoparticle is reported to modulate the deep microenvironment of PDAC for improved chemoimmunotherapy. The tumor pH‐sensitive polymer is synthesized by conjugating N,N‐dipentylethyl moieties and monomethoxylpoly(ethylene glycol) onto PAMAM dendrimer, into whose cavity a hydrophobic gemcitabine (Gem) prodrug is accommodated. They self‐assemble into nanoparticles (denoted as SPN@Pro‐Gem) with the size around 120 nm at neutral pH, but switch into small particles (≈8 nm) at tumor site to facilitate deep delivery of Gem into the tumor parenchyma. In addition to killing cancer cells that resided deeply in the tumor tissue, SPN@Pro‐Gem could modulate the TME by reducing the abundance of tumor‐associated macrophages and myeloid‐derived suppressor cells as well as upregulating the expression level of PD‐L1 of tumor cells. This collectively facilitates the infiltration of cytotoxic T cells into the tumors and renders checkpoint inhibitors more effective in previously unresponsive PDAC models. This study reveals a promising strategy for improving the chemoimmunotherapy of pancreatic cancer.
Alkaline Water Splitting Enhancement by MOF‐Derived Fe–Co–Oxide/Co@NC‐mNS Heterostructure: Boosting OER and HER through Defect Engineering and In Situ Oxidation
Authors: Singh Thangjam Ibomcha , Rajeshkhanna Gaddam , Pan Uday Narayan , Kshetri Tolendra , Lin Han , Kim Nam Hoon , Lee Joong Hee
Published: June 2021

Introducing defects and in situ topotactic transformation of the electrocatalysts generating heterostructures of mixed‐metal oxides(hydroxides) that are highly active for oxygen evolution reaction (OER) in tandem with metals of low hydrogen adsorption barrier for efficient hydrogen evolution reaction (HER) is urgently demanded for boosting the sluggish OER and HER kinetics in alkaline media. Ascertaining that, metal–organic‐framework‐derived freestanding, defect‐rich, and in situ oxidized Fe–Co–O/Co metal@N‐doped carbon (Co@NC) mesoporous nanosheet (mNS) heterostructure on Ni foam (Fe–Co–O/Co@NC‐mNS/NF) is developed from the in situ oxidation of micropillar‐like heterostructured Fe–Co–O/Co@NC/NF precatalyst. The in situ oxidized Fe–Co–O/Co@NC‐mNS/NF exhibits excellent bifunctional properties by demanding only low overpotentials of 257 and 112 mV, respectively, for OER and HER at the current density of 10 mA cm−2, with long‐term durability, attributed to the existence of oxygen vacancies, higher specific surface area, increased electrochemical active surface area, and in situ generated new metal (oxyhydr)oxide phases. Further, Fe–Co–O/Co@NC‐mNS/NF (+/−) electrolyzer requires only a low cell potential of 1.58 V to derive a current density of 10 mA cm−2. Thus, the present work opens a new window for boosting the overall alkaline water splitting.
Red Phosphorus Decorated TiO2 Nanorod Mediated Photodynamic and Photothermal Therapy for Renal Cell Carcinoma
Authors: Yang Chengyu , Zhu Yukun , Li Daohao , Liu Yiming , Guan Chen , Man Xiaofei , Zhang Shuchao , Zhang Lixue , Yang Dongjiang , Xu Yan
Published: June 2021

Clear cell renal cell carcinoma (ccRCC) is a serious and tenacious disease. Photodynamic therapy (PDT) and photothermal therapy (PTT) are effective means of cancer treatment. However, PDT combined with PTT has been rarely reported in ccRCC treatment. In the present study, by developing the core–shell structured TiO2@red phosphorus nanorods (TiO2@RP NRs) as a photosensitizer, the feasibility and effectiveness of synchronous PDT and PTT treatments for ccRCC are demonstrated. The core–shell structured TiO2@RP NRs are synthesized to drive the PDT and PTT for ccRCC, in which the RP shell is the sensitizer even in the near‐infrared (NIR) region. The optimized TiO2@RP NRs can respond to NIR and produce local heat under irradiation. The NRs are estimated in ccRCC treatments via cell counting kit‐8 assay, propidium iodide staining, qRT‐PCR, and reactive oxygen species (ROS) probes in vitro, while terminal deoxynucleotidyl transferase dUTP nick‐end labeling is conducted in vivo. After NIR irradiation, TiO2@RP NRs can efficiently kill ccRCC cells by producing local heat and ROS and cause low injury to normal kidney cells. Furthermore, treatment with TiO2@RP NRs and NIR can kill significant numbers of deep‐tissue ccRCC cells in vivo. This work highlights a promising photo‐driven therapy for kidney cancer.
Methods to Identify Immunogenic Peptides in SARS‐CoV‐2 Spike and Protective Monoclonal Antibodies in COVID‐19 Patients
Authors: Li Lili , Gao Meiling , Li Jie , Zu Shulong , Wang Yanan , Chen Chunfeng , Wan Dingyi , Duan Jing , Aliyari Roghiyh , Wang Jingfeng , Zhang Jicai , Jin Yujie , Huang Weijin , Jin Xiaoxia , Shi Minxin , Wang Youchun , Qin Cheng‐Feng , Yang Heng , Cheng Genhong
Published: June 2021

The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection and the associated COVID‐19 diseases are an emerging threat to global public health. Although considerable scientific research on the immune, especially antibody, responses to SARS‐CoV‐2 infection have been conducted, additional dominant epitopes and protective antibodies are needed for diagnosis and treatment of COVID‐19 patients. Here, two different phage libraries are used to identify immunogenic epitopes across the spike protein and monoclonal antibodies from COVID‐19 patients. Three peptides are further characterized in the receptor‐binding motif (RBM) and measured their antibody levels in COVID‐19 patients, from which one identifies one most immunodominant epitope with the highest antibody response in COVID‐19 patients and in immunized mice. More importantly, monoclonal antibodies specifically binding to this peptide isolated from COVID‐19 patients have therapeutic potential to neutralize SARS‐CoV‐2 infection. Thus, the approaches to systemically identify immunogenic peptides and directly identify human monoclonal antibodies from patients will provide useful diagnostic and therapeutic tools for COVID‐19 and other emerging infectious diseases.
Laser‐Ablated Red Phosphorus on Carbon Nanotube Film for Accelerating Polysulfide Conversion toward High‐Performance and Flexible Lithium–Sulfur Batteries
Authors: Lee Jeongyeon , Song Hyeonjun , Min Kyung‐Ah , Guo Qianyi , Kim Daekyu , Zheng Zijian , Han Byungchan , Jung Youngjin , Lee Lawrence Yoon Suk
Published: June 2021

The use of a conducting interlayer between separator and cathode is one of the most promising methods to trap lithium polysulfides (LiPSs) for enhancing the performance of lithium–sulfur (Li–S) batteries. Red phosphorus nanoparticles (RPEN)‐coated carbon nanotube (CNT) film (RPEN@CF) is reported herein as a novel interlayer for Li–S batteries, which shows strong chemisorption of LiPSs, good flexibility, and excellent electric conductivity. A pulsed laser ablation method is engaged for the ultrafast production of RPEN of uniform morphology, which are deposited on the CNT film by a direct spinning method. The RPEN@CF interlayer provides pathways for effective Li+ and electron transfer and strong chemical interaction with LiPSs. The S/RPEN@CF electrode shows a superior specific capacity of 782.3 mAh g−1 (3 C‐rate) and good cycling performances (769.5 mAh g−1 after 500 cycles at 1 C‐rate). Density functional theory calculations reveal that the morphology and dispersibility of RPEN are crucial in enhancing Li+ and electron transfer kinetics and effective trap of LiPSs. This work demonstrates the possibility of using the RPEN@CF interlayer for the enhanced electrochemical performances of Li–S batteries and other flexible energy storage devices.
Financial depth, income inequality, and economic transition
Authors: Chu Chi‐Yang , Jiang Mingming
Published: June 2021

This article examines the evolving finance–inequality nexus during the process of economic transition. We estimate the varying marginal effects of financial depth on income inequality in every state of the transition process. Using China as an example of transition economies, we establish the causal effects of financial depth on urban income inequality and examine the estimation biases when the evolving relationship is not appropriately characterized. Along the transition process of the Chinese economy, we identify a robustly asymmetric and roughly inverted‐L shaped relationship between financial depth and urban inequality. We find that financial depth alone accounts for 11–28% of the overall variations of urban income inequality and the marginal impacts of financial depth change with the degree of credit constraint, the fraction of state ownership, and the level of economic development.
Flux‐Mediated Wetting of Alumina by Liquid Fe–Ti–Csat
Authors: Britt Steven Thomas , Pistorius Petrus Christiaan
Published: June 2021

Metals do not wet oxides as a general rule. Exceptions to this occur in the presence of dissolved species or chemical reactions. Fe–Csat–Ti is seen to wet alumina crucibles but not crucibles of graphite or MgO. This is determined to be macroscopically due to reactive wetting of the ternary alloy on Al2O3; microscopically, the reaction formed a nanoscale layer of TiC on Al2O3, with the hot metal wetting the TiC substrate. Molten fluxes offer a way to mitigate the wetting of the alumina crucible by preventing the reaction. The liquid‐state Al2O3–CaF2 flux wets the Al2O3 crucible, coating both the crucible walls and bottom. This is effective in preventing wetting despite alumina activity being unity in the initial components. The volatilization of fluorine results in a calcium aluminate coating on the original crucible. Using the molten flux is more effective than sintering CA particles onto the crucible bottom because the liquid flux coated the crucible walls. Though wetting is a problem in industry, this offers practical mitigation of wetting using a flux coating.
Brandrisiko von E‐Fahrzeugen und kraftstoffbetriebenen Fahrzeugen in offenen, oberirdischen Parkgaragen: Teil 1: Brandszenarien und Brandeinwirkungen
Authors: Sander Lisa , Zehfuß Jochen , Meyer Patrick , Schaumann Peter
Published: June 2021

Im Zuge des klimapolitischen Diskurses in Deutschland nimmt der Anteil moderner Fahrzeuge und Antriebstechnologien in offenen, oberirdischen Parkgaragen zu. Aus Sicht des Brandschutzes stellt sich die Frage, ob durch Fahrzeuge mit modernen Antriebstechnologien wie Elektrofahrzeuge ein erhöhtes Brandrisiko sowie eine erhöhte Wärmefreisetzung zu erwarten sind. Im vorliegenden Beitrag wird ein methodischer Ansatz zur Bewertung des Brandrisikos von Elektrofahrzeugen gegenüber kraftstoffbetriebenen Fahrzeugen hinsichtlich des Feuerwiderstands des Tragwerks von Garagen vorgestellt. Dazu werden Modellierungsansätze der Fahrzeugabmessungen vorgestellt, die auf einer statistischen Auswertung der Daten des Kraftfahrt‐Bundesamts basieren. Die Fahrzeugabmessungen werden zur Bestimmung des Brandüberschlags zwischen Fahrzeugen angewendet. Weiterhin werden Wärmefreisetzungsraten verschiedener Fahrzeugmodelle analysiert, auf deren Basis ein approximierter Ansatz für moderne Fahrzeuge abgeleitet wird. Ferner werden mögliche Brandszenarien in offenen, oberirdischen Parkgaragen und die Auftretenswahrscheinlichkeiten von Fahrzeugkombinationen vorgestellt, um die Bauteiltemperaturen zu berechnen und die Versagenswahrscheinlichkeit von Einzelbauteilen in offenen, oberirdischen Parkgaragen unter Brandeinwirkungen von Elektrofahrzeugen zu bewerten.
Interacting Effects of Density‐Dependent and Density‐Independent Factors on Growth Rates in Southwestern Cutthroat Trout Populations
Authors: Huntsman Brock M. , Lynch Abigail J. , Caldwell Colleen A.
Published: June 2021

Density‐dependent (DD) and density‐independent (DI) effects play an important role in shaping fish growth rates, an attribute that correlates with many life history traits in fishes. Consequently, understanding the extent to which DD and DI effects influence growth rates is valuable for fisheries assessments because it can inform managers about how populations may respond as environmental conditions continue to change (e.g., threats from climate change). We used a Rio Grande Cutthroat Trout Oncorhynchus clarkii virginalis (RGCT) capture–mark–recapture data set collected over 2 years along a temperature and density gradient in northern New Mexico streams to test the extent to which DD and DI effects interact to influence specific growth rates. We found that temperature (DI) and density (DD) interacted with RGCT life stage (i.e., immature or mature) to affect growth rates. We only detected evidence of a negative DD effect on RGCT growth for the immature fraction of a population when exposed to the warmest stream temperatures. Our results suggest that competition most strongly affected the immature portion of RGCT populations, and this effect was only detectable when temperatures were warmest and energetic stress was likely at its highest. The quadratic relationship between temperature and growth rates also demonstrated that stream temperatures were below as well as above optimal growth temperatures for RGCT. Growth rates in our RGCT populations were influenced by complex interactions of DD and DI effects, and our results suggest that the negative consequences of warming trends associated with climate change on RGCT populations may be exacerbated by DD effects.