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Unconventional phonon spectra and obstructed edge phonon modes

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 114-118页

作者： Ruihan zhang Haohao sheng Junze Deng Zhong Fang Zhilong Yang Zhijun Wang Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Based on the elementary band representations(EBR),many topologically trivial materials are classified as unconventional ones(obstructed atomic limit),where the EBR decomposition for a set of electronic states is not consistent with atomic valenceelectron band *** the work,we identify that the unconventional nature can also exist in phonon spectra,where the EBR decomposition for a set of well-separated phonon modes is not consistent with atomic vibration band representations(ABR).The unconventionality has two types:typeⅠis on an empty site;and typeⅡis on an atom site with non-atomic vibration *** unconventionality is described by the nonzero real-space invariant at the *** detailed calculations show that the black phosphorus(BP)has the typeⅠunconventional phonon spectrum,while 1H-Mo Se_(2)has the typeⅡone,although their electronic structures are also ***,the obstructed phonon modes are obtained for two types of unconventional phonon spectra.

关键词： unconventional phonon spectra obstructed edge phonon mode typeⅠ&typeⅡunconventionality

Full sexual maturity-cycle exposure to environmentally relevant concentrations of 17β-estradiol decreases reproductive capacity of zebrafish

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Journal of Environmental Sciences 2024年第3期137卷 580-592页

作者： Yongkang zhang Yuanjun Jiang Qian Sun Meng Li sheng Chen Jingyu Liang Chunsheng Liu College of Fisheries Huazhong Agricultural UniversityWuhan 430070China School of Environmental Studies China University of GeosciencesWuhan 430074China

17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in ***,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of E2 for the full sexual maturation cycle remain *** this study,zebrafish were treatment with 0,10 or100 ng/L E2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were *** results showed that treatment with E2 lead to increased number of feminization in *** females,E2 decreased cumulative amount of spawning and inhibited the maturation of *** males,E2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of *** adverse effects on sperm might be responsible for the reduced fertilization observed in *** addition,treatment with E2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in ***,these results suggested that treatment with environmentally relevant concentrations of E2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.

关键词： Environmental estrogen Zebrafish Fecundity Gonadal development Endocrine disruption

High temperature treatment induced production of unreduced 2n pollen in Camellia oleifera

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Horticultural Plant Journal 2024年第3期10卷 879-896页

作者： Hongda Deng Xiaoyu zhang Song sheng Yuxun Huang Ziqi Ye Tongyue zhang Xing Liu Zhiqiang Han The Laboratory of Forestry Genetics Central South University of Forestry and TechnologyChangshaHunan 410004China Yuelushan Laboratory ChangshaHunan 410128China Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees of Ministry of Education Central South University of Forestry and TechnologyChangshaHunan 410004China National Forest and Seedling Workstation of Hunan Province The Forestry Department of Hunan ProvinceChangshaHunan 410004China

Unreduced gametes through chromosome doubling play a major role in the process of plant *** previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature *** study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in *** found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n *** the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell *** on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were *** male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly *** inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell ***,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n *** findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of ***.

关键词： Camellia oleifera Pollen mother cells(PMCs) High temperature Meiosis 2n pollen CoPGX3

Recent advances in bioinspired vision systems with curved imaging structures

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Rare Metals 2024年第4期43卷 1407-1434页

作者： Ze-Ping He Xun Han Wen-Qiang Wu zhang-sheng Xu Cao-Feng Pan CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing100049China ZJU-Hangzhou Global Scientific and Technological Innovation Center School of Micro-Nano ElectronicsZhejiang UniversityHangzhou311200China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen518060China

Limited by the planar imaging structure,the commercial camera needs to introduce additional optical elements to compensate for the curved focal plane to match the planar image *** results in a complex and bulky *** contrast,biological eyes possess a simple and compact structure due to their curved imaging structure that can directly match with the curved focal *** by the structures and functions of biological eyes,curved vision systems not only improve the image quality,but also offer a variety of advanced ***,we review the recent advances in bioinspired vision systems with curved imaging ***,we focus on their applications in implementing different functions of biological eyes,as well as the emerging curved neuromorphic imaging systems that incorporate bioinspired optical and neuromorphic processing *** addition,the challenges and opportunities of bioinspired curved imaging systems are also discussed.

关键词： Bioinspired Curved vision system Compound eye Chambered eye Neuromorphic

Enhancing microseismic/acoustic emission source localization accuracy with an outlier-robust kernel density estimation approach

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International Journal of Mining Science and Technology 2024年第7期34卷 943-956页

作者： Jie Chen Huiqiong Huang Yichao Rui Yuanyuan Pu sheng zhang Zheng Li Wenzhong Wang State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Central South UniversityChangsha 410083China Chongqing City Construction Investment Group Co. Ltd.Chongqing 400023China Coal Geological Exploration Institute of Gansu Lanzhou 730000China

Monitoring sensors in complex engineering environments often record abnormal data,leading to significant positioning *** reduce the influence of abnormal arrival times,we introduce an innovative,outlier-robust localization method that integrates kernel density estimation(KDE)with damping linear correction to enhance the precision of microseismic/acoustic emission(MS/AE)source *** approach systematically addresses abnormal arrival times through a three-step process:initial location by 4-arrival combinations,elimination of outliers based on three-dimensional KDE,and refinement using a linear correction with an adaptive damping *** validate our method through lead-breaking experiments,demonstrating over a 23%improvement in positioning accuracy with a maximum error of 9.12 mm(relative error of 15.80%)—outperforming 4 existing *** under various system errors,outlier scales,and ratios substantiate our method’s superior *** blasting experiments also confirm the practical applicability,with an average positioning error of 11.71 m(relative error of 7.59%),compared to 23.56,66.09,16.95,and 28.52 m for other *** research is significant as it enhances the robustness of MS/AE source localization when confronted with data *** also provides a practical solution for real-world engineering and safety monitoring applications.

关键词： Microseismic source/acoustic emission(MS/AE) Kernel density estimation(KDE) Damping linear correction Source location Abnormal arrivals

Modulation of d-orbital to realize enriched electronic cobalt sites in cobalt sulfide for enhanced hydrogen evolution in electrocatalytic water/seawater splitting

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Rare Metals 2024年第2期43卷 511-521页

作者： Jian-Peng Sun Yu Zheng Zi-sheng zhang Xiang-Chao Meng Zi-Zhen Li Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao266100China Shanxi Institute of Energy Taiyuan030600China Department of Chemical and Biological Engineering Faculty of EngineeringUniversity of OttawaOttawaONK1N6 N5Canada

Herein,a novel single-atomic Pt doping and interface-rich CoS/Co(OH)_(2)(Pt-CoS/Co(OH)_(2)/C)electrocatalyst has been successfully *** from precise regulation of d-orbital electronic structure modulation on Co site,Pt-CoS/Co(OH)_(2)/C exhibited remarkable HER activity and high stability for hydrogen evolution in splitting both water(73 mV@10 mA·cm^(−2)) and seawater(87 mV@10 mA·cm^(−2)).Notably,atomic Pt doping was introduced into CoS/Co(OH)_(2),which could produce local unbalanced Coulombic force and significantly increased the number of S vacancies,and then expose abundant Co ***,Co(OH)_(2) in Pt-CoS/Co(OH)_(2)/C could act as the adsorption sites for H_(2)O in hydrogen evolution reaction *** functional theory results also proved that atomic Pt doping,S vacancies and Co(OH)_(2) coupling could result in the formation of enriched electronic Co sites and optimize d_(z2) orbital electronic structure,and then realize the depth upward shift of d-band center and enhance the adsorption of H*on Co sites.

关键词： Electrocatalysts Hydrogen evolution reaction Pt-CoS/Co(OH)_(2) d-band center Electronic structure Water/seawater electrolysis

Superjunction 4H-SiC trench-gate IGBT with an integrated clamping PN diode

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 3-9,27页

作者： Huang Yi Wang Xuecheng Gao sheng Liu Bin zhang Hongsheng Han Genquan School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic Science and Engineering Nanjing UniversityNanjing 210008China School of Microelectronics Xidian UniversityXi'an 710126China

In this paper,a novel superjunction 4H-silicon carbide(4H-SiC)trench-gate insulated-gate bipolar transistor(IGBT)featuring an integrated clamping PN diode between the P-shield and emitter(TSD-IGBT)is designed and theoretically *** heavily doping superjunction layer contributes to a low specific on-resistance,excellent electric field distribution,and quasi-unipolar drift *** anode of the clamping diode is in floating contact with the *** the on-state,the potential of the P-shield is raised to the turn-on voltage of the clamping diode,which prevents the hole extraction below the N-type carrier storage layer(NCSL).Additionally,during the turn-off transient,once the clamping diode is turned on,it also promotes an additional hole extraction ***,the potential dropped at the semiconductor near the trench-gate oxide is effectively reduced in the off-state.

关键词： 4H-silicon carbide(4H-SiC) trench-gate superjunction clamping diode

Response characteristics of PWR primary circuit under SBLOCAs considering steam bypass discharging

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Nuclear Science and Techniques 2024年第6期35卷 189-201页

作者： Shuai Yang Xiang-Bin Li Yu-sheng Liu Jia-Ning Xu De-Chen zhang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy Beijing 102206China Nuclear and Radiation Safety Center MEPBeijing 100084China

Small-break superposed station blackout(SBO)accidents are the basic design accidents of nuclear power *** the condition of a small break in the cold leg,SBO further increases the severity of the accident,and the steam bypass discharg-ing system(GCT)in the second circuit can play an important role in guaranteeing core *** explore the influence of the GCT on the thermal-hydraulic characteristics of the primary circuit,RELAP5 software was used to establish a numerical model based on a typical pressurized water reactor nuclear power *** different small breaks in the cold-leg super-posed SBO were selected,and the impact of the GCT operation on the transient response characteristics of the primary and secondary circuit systems was *** results show that the GCT plays an indispensable role in core heat removal during an accident;otherwise,core safety cannot be *** GCT was used in conjunction with the primary safety injection system during the placement *** the break diameter was greater than a certain critical value,the core cooling rate could not be guaranteed to be less than 100 K/h;however,the core remained in a safe state.

关键词： Steam bypass discharging Pressurized water reactor SBLOCA Numerical simulation

Review on dietary supplements as an effective improvement of Alzheimer's disease:focus on structures and mechanisms

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Food Science and Human Wellness 2024年第4期13卷 1787-1805页

作者： sheng Li Yinling Wei Zhenzhen Liang Lingli Guo Xiaojiang Hao Yu zhang State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China College of Traditional Chinese Materia Medica Shenyang Pharmaceutical UniversityShenyang 110016China

Alzheimer’s disease(AD),the major form of neurodegenerative diseases that can severely impede normal cognitive function,makes it one of the most common fatal *** are currently over 50 million AD patients *** neuropathology of AD is perplexing and there is a scarcity of disease-modifying ***,early diagnosis of AD has been made possible with the discovery of biological markers associated with pathology,providing strong support for the improvement of the disease *** search for inhibitors of AD markers from dietary supplements(DSs)has become a major hot *** with the widespread use of DSs,DSs containing polyphenols,alkaloids,terpenes,polysaccharides and other bioactive components can prevent AD by reducing Aβdeposition,inhibiting tau protein hyperphosphorylation,reconstructing synaptic dysfunction,weakening cholinesterase activity,regulating mitochondrial oxidative stress,neuronal inflammation and *** review summarizes the anti-AD effects of the main DSs and their bioactive constituents,as well as the potential molecular mechanisms covers from 2017 to ***,we discussed the opportunities and challenges faced by DSs in the process of AD prevention and treatment,aiming to further provide new perspectives for functional food development.

关键词： Dietary supplements Bioactive ingredients Alzheimer’s disease Mechanism of action