Seismic displacement demand prediction in non-linear domain: Optimization of the N2 method

In Europe, computation of displacement demand for seismic assessment of existing buildings is essentially based on a simplified formulation of the N2 method as prescribed by Eurocode 8(EC8). However, a lack of accuracy of the N2 method in certain conditions has been pointed out by several studies. This paper addresses the assessment of effectiveness of the N2 method in seismic displacement demand determination in non-linear domain. The objective of this work is to investigate the accuracy of the N2 method through comparison with displacement demands computed using non-linear timehistory analysis(NLTHA). Results show that the original N2 method may lead to overestimation or underestimation of displacement demand predictions. This may affect results of mechanical model-based assessment of seismic vulnerability at an urban scale. Hence, the second part of this paper addresses an improvement of the N2 method formula by empirical evaluation of NLTHA results based on EC8 ground-classes. This task is formulated as a mathematical programming problem in which coefficients are obtained by minimizing the overall discrepancy between NLTHA and modified formula results. Various settings of the mathematical programming problem have been solved using a global optimization metaheuristic. An extensive comparison between the original N2 method formulation and optimized formulae highlights benefits of the strategy.

Genetic and biological properties of H9N2 avian influenza viruses isolated in central China from2020 to 2022

The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by serving as a"donor virus")infect humans,posing a significant threat to public health.Currently,there is a lack of in-depth research on the prevalence of H9N2 viruses in Shanxi Province,central China.In this study,we isolated 14 H9N2 AIVs from October 2020 to April 2022 in Shanxi Province,and genetic analysis revealed that these viruses belonged to 7 different genotypes.Our study on animals revealed that the H9N2 strains we identified displayed high transmission efficiency among chicken populations,and exhibited diverse replication abilities within these birds.These viruses could replicate efficiently in the lungs of mice,with one strain also demonstrating the capacity to reproduce in organs like the brain and kidneys.At the cellular level,the replication ability of different H9N2 strains was evaluated using plaque formation assays and multi-step growth curve assays,revealing significant differences in the replication and proliferation efficiency of the various H9N2 viruses at the cellular level.The antigenicity analysis suggested that these isolates could be classified into 2 separate antigenic clusters.Our research provides crucial data to help understand the prevalence and biological characteristics of H9N2 AIVs in central China.It also highlights the necessity of enhancing the surveillance of H9N2 AIVs.

Estrogen affects neuropathic pain through upregulating N-methyl-D-aspartate acid receptor 1 expression in the dorsal root ganglion of rats

Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1（NMDAR1） plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D（-）-2-amino-5-phosphonopentanoic acid（AP-5）,or both once daily for 15 days.Compared with injured drug na？ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity（as assessed by immunohistochemistry） and protein（as determined by western blot assay） in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia.

The Extended Tanh Method for Compactons and Solitons Solutions for the CH(<i>n</i>,2<i>n</i>– 1,2<i>n</i>,–<i>n</i>) Equations

In this paper, by using the sine-cosine method, the extended tanh-method, and the rational hyperbolic functions method, we study a class of nonlinear equations which derived from a fourth order analogue of generalized Camassa-Holm equation. It is shown that this class gives compactons, solitary wave solutions, solitons, and periodic wave solutions. The change of the physical structure of the solutions is caused by variation of the exponents and the coefficients of the derivatives.

Pathogenicity and amino acid sequences of hemagglutinin cleavage site and neuraminidase stalk of differently passaged H9N2-avian influenza virus in broilers

Low pathogenic Avian Influenza (AI) virus has the ability to evolve to high pathogenic viruses resulting in significant economic losses in the poultry sector. This study aims at assessing the impact of H9N2 viral passaging in broilers and its relatedness to pathogenicity and amino acid (a.a) sequences of the hemagglutinin (HA) cleavage site and neuraminidase (NA) stalk. The original H9N2 AI virus (P0) was used to challenge ten-21 days old broilers. Individual recovery of H9N2 virus from homogenates of trachea, lungs and airsacs was attempted in 9 days old chicken embryos, as a conclusion of the first passage (P1). Tracheal isolates of H9N2 were passaged for a second (P2) and a third (P3) time in broilers, followed by a similar embryonic recovery procedure. The a.a. sequence of a part of HA1 cleavage site and Neuraminidase stalk were compared among the differently passaged viruses;an assessement of the relatedness of the determined a.a. sequences to the pathogenicity in broilers, based on frequency of mortality, morbidity signs, gross and microscopic lesions at 3 days post challenge with the P1, P2, and P3-H9N2, is concluded. An increase in certain morbidity signs and specific lesions was observed in P2- and P3-H9N2 challenged broilers compared to birds challenged with P1-H9N2. A conserved R-S-S-R amino acid sequence at the HA1 cleavage site was observed in the differently passaged H9N2, associated with a variability in the NA stalk-a.a sequences. The passaging of the low pathogenic H9N2 virus in broilers leads to a trend of increase in pathogenicity, manifested in higher frequency of morbidity signs, and of specific gross and microscopic lesions of the examined organs. This passaging was associated with a conserved a.a. sequence of the hemaglutinin cleavage site and a variability in the sequence of the neuraminidase stalk. A detailed study of the potential of the detected variability in the neuraminidase stalk of H9N2 in induction of a higher pathogenicity in broilers will be the subject of future investigations.

Exploring pore-scale production characteristics of oil shale after CO_(2) huff‘n’puff in fractured shale with varied permeability

Recent studies have indicated that the injection of carbon dioxide(CO_(2))can lead to increased oil recovery in fractured shale reservoirs following natural depletion.Despite advancements in understanding mass exchange processes in subsurface formations,there remains a knowledge gap concerning the disparities in these processes between the matrix and fractures at the pore scale in formations with varying permeability.This study aims to experimentally investigate the CO_(2) diffusion behaviors and in situ oil recovery through a CO_(2) huff‘n’puff process in the Jimsar shale oil reservoir.To achieve this,we designed three matrix-fracture models with different permeabilities(0.074 mD,0.170 mD,and 0.466 mD)and experimented at 30 MPa and 91°C.The oil concentration in both the matrix and fracture was monitored using a low-field nuclear magnetic resonance(LF-NMR)technique to quantify in situ oil recovery and elucidate mass-exchange behaviors.The results showed that after three cycles of CO_(2) huff‘n’puff,the total recovery degree increased from 30.28%to 34.95%as the matrix permeability of the core samples increased from 0.074 to 0.466 mD,indicating a positive correlation between CO_(2) extraction efficiency and matrix permeability.Under similar fracture conditions,the increase in matrix permeability further promoted CO_(2) extraction efficiency during CO_(2) huff‘n’puff.Specifically,the increase in matrix permeability of the core had the greatest effect on the extraction of the first-cycle injection in large pores,which increased from 16.42%to 36.64%.The findings from our research provide valuable insights into the CO_(2) huff‘n’puff effects in different pore sizes following fracturing under varying permeability conditions,shedding light on the mechanisms of CO_(2)-enhanced oil recovery in fractured shale oil reservoirs.

Molecular Docking and ADMET Study of Emodin Derivatives as Anticancer Inhibitors of NAT2, COX2 and TOP1 Enzymes

Over the past years natural products and/or their derivatives have continued to provide cancer chemotherapeutics. Glycosides derivatives of emodin are known to possess anticancer activities. An in silico study was carried out to evaluate emodin derivatives as inhibitors of Arylamine N-Acetyltransferase 2, Cyclooxygenase 2 and Topoisomerase 1 enzymes, predict their pharmacokinetics and explore their bonding modes. Molecular docking study suggested that D2, D5, D6 and D9 to be potent inhibitors of NAT2, while D8 was suggested to be a potent inhibitor of TOP1. Derivatives D2, D5, D6 and D9 bind to the same pocket with different binding conformation. Pharmacokinetic study suggested that selected emodin derivatives can be potential cancer chemotherapeutic agent. Physicochemical parameters such density, balaban index, surface tension, logP and molar reflectance correlated to compounds activity. These finding provides a potential strategy towards developing NAT2 and TOP1 inhibitors.

Effect of Temperature on the Reaction of 2-(N-acetylamine)-3-(3,5-di-<i>tert</i>-butyl-4-hydroxyphenyl)-propionic Acid with Oxygen in an Alkaline Condition

Results of oxidation 2-(N-acetylamine)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid oxygen depend on temperature. At 55℃?- 60℃, 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa is formed. The constitution is based on dates of spectrums 1Н and 13С NMR. At 95℃?- 97℃, mixtures of 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa and of 6,8-di-tert-butyl-3-(N-acetylamine)spiro(4,5)deca-1-oxa-5,8-dien-2,7-dione are produced. Structures are calculated by the method of Hartrii-Foka. Values of enthalpies and of entropies allow to assume dynamic isomerism.

nForce2主板介绍与评析

NFII Ultra是DFI公司LANParty系列产品中的一员，顾名思义，该主板的用户是可以背着自己的机器去和朋友联机Party的，而NFII Ultra主板就提供了一个机箱背囊!除此以外，NFII Ultra还十分重视主板的视觉效果，棕黑色的PCB加上绿色的插槽，再配上荧光绿的Cable数据线等等。除了外观的别致之外，NFII Ultra也确实有几点特别之处，使得它适合于脱离机箱使用．比如主板上集成了开关和重启的按钮，另外它还配有4个LED灯用于显示错误信息，而且主板四角做得非常圆整。

Enhancing Green Ammonia Electrosynthesis Through Tuning Sn Vacancies in Sn‑Based MXene/ MAX Hybrids

Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel Sn-based MXene/MAX hybrid with abundant Sn vacancies,Sn@Ti_(2)CTX/Ti_(2)SnC–V,was synthesized by controlled etching Sn@Ti_(2)SnC MAX phase and demonstrated as an efficient electrocatalyst for electrocatalytic N2 reduction.Due to the synergistic effect of MXene/MAX heterostructure,the existence of Sn vacancies and the highly dispersed Sn active sites,the obtained Sn@Ti2CTX/Ti_(2)SnC–V exhibits an optimal NH_(3) yield of 28.4μg h^(−1) mg_(cat)^(−1) with an excellent FE of 15.57% at−0.4 V versus reversible hydrogen electrode in 0.1 M Na_(2)SO_(4),as well as an ultra-long durability.Noticeably,this catalyst represents a satisfactory NH3 yield rate of 10.53μg h^(−1) mg^(−1) in the home-made simulation device,where commercial electrochemical photovoltaic cell was employed as power source,air and ultrapure water as feed stock.The as-proposed strategy represents great potential toward ammonia production in terms of financial cost according to the systematic technical economic analysis.This work is of significance for large-scale green ammonia production.

Current Status and Perspectives of Dual-Atom Catalysts Towards Sustainable Energy Utilization

The exploration of sustainable energy utilization requires the imple-mentation of advanced electrochemical devices for efficient energy conversion and storage,which are enabled by the usage of cost-effective,high-performance electro-catalysts.Currently,heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of applications.Compared to conventional cata-lysts,atomically dispersed metal atoms in carbon-based catalysts have more unsatu-rated coordination sites,quantum size effect,and strong metal-support interactions,resulting in exceptional catalytic activity.Of these,dual-atomic catalysts(DACs)have attracted extensive attention due to the additional synergistic effect between two adja-cent metal atoms.DACs have the advantages of full active site exposure,high selectiv-ity,theoretical 100%atom utilization,and the ability to break the scaling relationship of adsorption free energy on active sites.In this review,we summarize recent research advancement of DACs,which includes(1)the comprehensive understanding of the synergy between atomic pairs;(2)the synthesis of DACs;(3)characterization meth-ods,especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy;and(4)electrochemical energy-related applications.The last part focuses on great potential for the electrochemical catalysis of energy-related small molecules,such as oxygen reduction reaction,CO_(2) reduction reaction,hydrogen evolution reaction,and N_(2) reduction reaction.The future research challenges and opportunities are also raised in prospective section.

Dim-YOLOv5n昏暗场景目标检测算法

相比于正常光照场景,照明不良昏暗场景干扰因素较多,图像处理较为复杂,且现有的昏暗目标检测,存在参数量大,识别准确率低等不足。针对昏暗场景下目标检测算法中存在误检与漏检等问题,提出以YOLOv5n算法为基础进行改进的昏暗场景目标检测算法Dim-YOLOv5n。利用嵌入全维动态卷积(omni-dimensional dynamic convolution,ODConv)的轻量化主干ODConv-MobileNetV2替换主干网络,在减少计算量的同时提高检测精度。基于RepGFPN(reparameterized generalized-FPN)方法设计更加轻量高效的LigGFPN(lightweight generalized-FPN)加强特征融合网络,以提高网络特征提取能力,并在此基础上,使用GhostConv(ghost convolution)替换传统卷积,以减少模型的参数量。实验结果表明,改进后算法与原算法相比,检测精度P和召回率R分别提高了5.3个百分点和5个百分点,平均精度均值mAP0.5:0.95和mAP0.5分别提升了8.2个百分点和4.6个百分点,改进的算法在保证模型较小的同时有效提高了检测准确率。

THE (n, 2n) CROSS-SECTION FOR Na—23 BETWEEN E_n=13.3—18.5 MeV

The （n,2n） cross- section for 23Na have been measured by the activation method in the energy range of En=13.3—18.5 MeV. Monoenergetic neutrons were obtained from T（d,n） 4He reaction at Ed=2.3 MeV. The induced specific activities were detected by a coincidence counting setup. For comparison, the other measured, evaluated and calculated data from En=12—20 MeV are also given.

Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques

Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion reactors.At the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He reaction.The^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of Sciences.The neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb reaction.The measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature data.The newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental values.The obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc.

COVID-19 Patient with Multifocal Pneumonia and Respiratory Difficulty Resolved Quickly: Possible Antiviral and Anti-Inflammatory Benefits of Quercinex (Nebulized Quercetin-NAC) as Adjuvant

Background: SARS-CoV-2 (COVID-19) is a viral pandemic with no current vaccine or effective treatment. Hydroxychloroquine and azithromycin are not without cardiovascular risk or complications, and these treatments can fail to aid in full recovery from COVID-19. As new treatments become approved for the pandemic, an inexpensive, non-toxic, and safe adjunctive therapy is needed. Case Presentation: A 59-year-old male presented with respiratory symptoms. Chest X-ray revealed classic indications of COVID-19 pneumonia. A PCR nasopharyngeal swab test confirmed a COVID-19 infection and hospital doctors prescribed Rocephin, azithromycin, and hydroxychloroquine. The patient was then prescribed Quercinex, a nebulized formula of quercetin-(cyclodextrin) (20 mg/mL) and N-acetylcysteine (100 mg/mL) three times daily for 14 days by physicians at Envita Medical Center for continued COVID-19 respiratory symptoms. Following 30 minutes after each nebulization treatment, the patient experienced immediate deep breathing relief that lasted for multiple hours. Within the following 48 hours after the first treatment, respiratory symptoms continued to diminish and resolve quickly. Finally, post-treatment follow-up chest X-rays revealed no pulmonary fibrosis (scarring) and clear lung fields. Conclusion: The Quercinex formula appeared to greatly alleviate the unresolved respiratory symptoms rapidly. Several mechanisms of the formula, namely antiviral and anti-inflammatory action, with direct administration via nebulizer to the deep lung tissue, could potentially explain the fast and complete recovery. We recommend that the Quercinex formula be considered for further clinical study as an adjuvant or on its own for COVID-19 and possibly other viral pulmonary conditions.

8-hydroxy-2-(di-n-propylamino)tetralin intervenes with neural cell apoptosis following diffuse axonal injury

Previous studies have reported a neuroprotective effect of 8-hydroxy-2-（di-n-propylamino）tetralin （8-OH-DPAT） against traumatic brain injury. In accordance with the Marmarou method, rat models of diffuse axonal injury were established. 8-OH-DPAT was intraperitoneally injected into model rats. 8-OH-DPAT treated rats maintained at constant temperature served as normal temperature controls TUNEL results revealed that neural cell swelling, brain tissue necrosis and cell apoptosis occurred around the injured tissue. Moreover, the number of Bax-, Bcl-2- and caspase-3-positive cells increased at 6 hours after diffuse axonal injury, and peaked at 24 hours. However, brain injury was attenuated, the number of apoptotic cells reduced, Bax and caspase-3 expression decreased, and Bcl-2 expression increased at 6, 12, 24, 72 and 168 hours after diffuse axonal injury in normal temperature control and in 8-OH-DPAT-intervention rats. The difference was most significant at 24 hours. All indices in 8-OH-DPAT-intervention rats were better than those in the constant temperature group. These results suggest that 8-OH-DPAT inhibits Bax and caspase-3 expression, increases Bcl-2 expression, and reduces neural cell apoptosis, resulting in neuroprotection against diffuse axonal injury. This effect is associated with a decrease in brain temperature.

Activation of Transition Metal(Fe,Co and Ni)-Oxide Nanoclusters by Nitrogen Defects in Carbon Nanotube for Selective CO_(2) Reduction Reaction

The electrochemical carbon dioxide reduction reaction(CO_(2)RR),which can produce value-added chemical feedstocks,is a proton-coupled-electron process with sluggish kinetics.Thus,highly efficient,cheap catalysts are urgently required.Transition metal oxides such as CoO_(x),FeO_(x),and NiO_(x)are low-cost,low toxicity,and abundant materials for a wide range of electrochemical reactions,but are almost inert for CO_(2)RR.Here,we report for the first time that nitrogen doped carbon nanotubes(N-CNT)have a surprising activation effect on the activity and selectivity of transition metal-oxide(MO_(x)where M=Fe,Ni,and Co)nanoclusters for CO_(2)RR.MO_(x)supported on N-CNT,MO_(x)/N-CNT,achieves a CO yield of 2.6–2.8 mmol cm−2 min−1 at an overpotential of−0.55 V,which is two orders of magnitude higher than MO_(x)supported on acid treated CNTs(MO_(x)/O-CNT)and four times higher than pristine N-CNT.The faraday efficiency for electrochemical CO_(2)-to-CO conversion is as high as 90.3%at overpotential of 0.44 V.Both in-situ XAS measurements and DFT calculations disclose that MO_(x)nanoclusters can be hydrated in CO_(2)saturated KHCO_(3),and the N defects of N-CNT effectively stabilize these metal hydroxyl species under carbon dioxide reduction reaction conditions,which can split the water molecules and provide local protons to inhibit the poisoning of active sites under carbon dioxide reduction reaction conditions.

IGF_(2)BP_(1)调控lncRNA NEAT1在类风湿关节炎中的作用

目的:类风湿关节炎(rheumatoid arthritis,RA)是一种常见的全身性自身免疫疾病,可能导致关节变形和功能障碍。本研究旨在探索胰岛素样生长因子-2 mRNA结合蛋白1(insulin like growth factor 2 mRNA binding protein 1,IGF_(2)BP_(1))在RA中的表达水平,以及其对长链非编码RNA(long non-coding RNA,lncRNA)核丰富转录本1(nuclear paraspeckle assembly transcript 1,NEAT1)稳定性的影响和在RA发病机制中的作用。方法:通过GEO(Gene Expression Omnibus)数据库获取RA数据集,并将其分为正常对照组和RA组,使用R软件分析获取N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)相关的甲基化酶的表达量并进行差异分析。分析差异表达的m^(6)A甲基化酶与lncRNA NEAT1的相关性。通过在线网站ENCORI预测与lncRNA NEAT1结合的蛋白质,并与lncRNA NEAT1表达相关的m^(6)A甲基化酶取交集,从而获取关键基因。通过RNA蛋白质相互作用分析实验(RNA pull-down)验证在RA滑膜细胞中NEAT1与关键基因结合的情况。通过蛋白质印迹法验证关键基因在正常滑膜细胞和RA滑膜细胞中的表达水平。在RA滑膜细胞中转染关键基因的小干扰RNA,通过real-time RT-PCR检测NEAT1在滑膜细胞中的表达水平。结果:差异分析结果显示:与正常对照组相比,共有8个m^(6)A甲基化基因在RA组中存在差异表达,其中IGF_(2)BP_(1)、甲基转移酶样蛋白14(methyltransferase 14,N^(6)-adenosine-methyltransferase subunit,MEEEL14)与lncRNA NEAT1存在相关性;ENCORI预测结果显示:共有23个蛋白质能够与lncRNA NEAT1结合,与NEAT1共表达m^(6)A甲基化酶取交集,获得NEAT1相关m^(6)A甲基化蛋白IGF_(2)BP_(1)。蛋白质印迹法显示:与正常对照组相比,RA组中IGF_(2)BP_(1)蛋白在RA滑膜细胞中表达升高(P<0.05);RNA pull-down结果显示IGF_(2)BP_(1)蛋白与NEAT1结合;real-time RT-PCR的结果表明:敲减IGF_(2)BP_(1)可显著降低NEAT1 mRNA表达水平(P<0.01)。结论:IGF_(2)BP_(1)可能通过稳定lncRNA NEAT1表达参与RA发病,调控IGF_(2)BP_(1)水平可能是一种新的治疗RA的方法。

Intensive-visible-light-responsive ANbO_(2)N(A = Sr, Ba) synthesized from layered perovskite A_(5)Nb_(4)O_(15) for enhanced photoelectrochemical water splitting

Nb-based, perovskite-type oxynitrides ANb(O,N)_(3)(A = Sr, Ba) have been significantly attractive semiconductor materials for photoelectrochemical(PEC) water splitting due to their absorption abilities of intensive-visible-light. However, PEC activities of these perovskites are relatively low due to reduction of Nb species during nitridation leading to the generation of anion defects and impurity phases.Herein, we propose nitridation of A-rich, layered perovskite A_(5)Nb_(4)O_(15) as starting oxides for general synthesis of photoactive ANbO_(2)N. These layered perovskite A_(5)Nb_(4)O_(15) were completely transformed to single phase perovskite-type ANbO_(2)N by nitridation. Wavelength onsets of light absorption were observed at 700 nm for SrNbO_(2)N and at 740 nm for BaNbO_(2)N. According to X-ray photoelectron spectroscopy results,excess Lewis base A species significantly suppressed the generation of reduced species such as Nb^(4+) and Nb^(3+)during nitridation, although it led to an amorphous surface of the as-prepared oxynitride.Subsequent annealing in Ar largely enhanced surface crystallinity of ANbO_(2)N. As a result, Co(OH)_(x)/ANbO_(2)N/FTO photoanodes, prepared by loading Co(OH)_(x) electrocatalyst, showed high photocurrent density of 1.6(A = Sr) and 2.4 m A cm^(-2)(A = Ba) at 1.23 VRHEunder AM 1.5 G simulated sunlight. These results demonstrate that A-rich layered perovskite A_(5)Nb_(4)O_(15)are effective starting precursors for preparing lowdefective ANbO_(2)N, thus improving PEC water splitting activity.

Numerical Analysis on the Effect of n-Si on Cu(In, Ga)Se2 Based Thin-Films for High-Performance Solar Cells by 1D-SCAPS

We report the performances of a chalcopyrite Cu(In, Ga)Se2 CIGS-based thin-film solar cell with a newly employed high conductive n-Si layer. The data analysis was performed with the help of the 1D-Solar Cell Capacitance Simulator (1D-SCAPS) software program. The new device structure is based on the CIGS layer as the absorber layer, n-Si as the high conductive layer, i-In2S3, and i-ZnO as the buffer and window layers, respectively. The optimum CIGS bandgap was determined first and used to simulate and analyze the cell performance throughout the experiment. This analysis revealed that the absorber layer’s optimum bandgap value has to be 1.4 eV to achieve maximum efficiency of 22.57%. Subsequently, output solar cell parameters were analyzed as a function of CIGS layer thickness, defect density, and the operating temperature with an optimized n-Si layer. The newly modeled device has a p-CIGS/n-Si/In2S3/Al-ZnO structure. The main objective was to improve the overall cell performance while optimizing the thickness of absorber layers, defect density, bandgap, and operating temperature with the newly employed optimized n-Si layer. The increase of absorber layer thickness from 0.2 - 2 µm showed an upward trend in the cell’s performance, while the increase of defect density and operating temperature showed a downward trend in solar cell performance. This study illustrates that the proposed cell structure shows higher cell performances and can be fabricated on the lab-scale and industrial levels.