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Rational design of bimetallic catalysts for electrochemical CO_(2)reduction reaction:A review

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Science China Chemistry 2023年第5期66卷 1288-1317页

作者： Minhan Li Jia-nan Zhang College of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

The electrochemical CO_(2)reduction reaction(eCO_(2)RR)is a compelling approach to convert CO_(2)into high-value fuels and chemicals using renewable *** rational design of catalysts is of great importance for achieving outstanding performance of this ***-based catalysts have been drawing enormous attention in eCO_(2)RR due to their excellent catalytic performance and flexible *** the pursuit of overcoming the inherent disadvantages of monometallic catalysts and achieving breakthroughs in the catalytic performance,bimetallic strategy has been receiving extensive concerns and achieving remarkable results over *** this review,we attempt to give a comprehensive review on the bimetallic catalysts that are used for eCO_(2)*** effects in bimetallic catalysts that contribute to the enhanced eCO_(2)RR performance are first analyzed,demonstrating the superiority of bimetallic ***,the structural design of bimetallic catalysts is discussed as it plays a key role in eCO_(2)***,the current advances and rules of selectivity of bimetallic catalysts in eCO_(2)RR are summarized based on the selectivity *** reviewing efforts devoted in this field,this review is believed to present a timely overview of the progress of bimetallic eCO_(2)RR catalysts and to offer potential future directions in the aim of developing highly efficient catalysts for eCO_(2)RR.

关键词： electrochemical CO_(2)reduction bimetallic catalyst electronic effect tandem effect structural design

Infinite Horizon Backward Doubly Stochastic Differential Equations with Non-degenerate Terminal Functions and Their Stationary Property

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 407-422页

作者： Hui-nan LENG Department of Mathematics East China University of Science and Technology

In this paper we consider infinite horizon backward doubly stochastic differential equations （BDS- DEs for short） coupled with forward stochastic differential equations, whose terminal functions are non-degenerate. For such kind of BDSDEs, we study the existence and uniqueness of their solutions taking values in weighted Lp（dx）¤L2（dx）space （p _〉 2）, and obtain the stationary property for the solutions.

关键词： backward doubly stochastic differential equations infinite horizon non-degenerate terminal func-tion stationary property

Tailoring biochar by PHP towards the oxygenated functional groups(OFGs)-rich surface to improve adsorption performance

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Chinese Chemical Letters 2022年第6期33卷 3097-3100页

作者： Xinyue Xiong zhanglin Liu Li Zhao Mei Huang Lichun Dai Dong Tian Jianmei Zou Yongmei Zeng Jinguang Hu Fei Shen Institute of Ecological and Environmental Sciences Sichuan Agricultural UniversityChengdu 611130China Rural Environment Protection Engineering&Technology Center of Sichuan Province Sichuan Agricultural UniversityChengdu 611130China Key Laboratory of Development and Application of Rural Renewable Energy Biogas Institute of Ministry of Agriculture and Rural AffairsChengdu 610041China Chemical and Petroleum Engineering Schulich School of Engineeringthe University of CalgaryCalgary T2N4H9Canada

In this work,a modification method of H_(3)PO_(4)plus H_(2)O_(2)(PHP)was introduced to targetedly form abundant oxygenated functional groups(OFGs)on biochar,and methylene blue(MB)was employed as a model pollutant for adsorption to reflect the modification *** indicated that parent biochars,especially derived from lower temperatures,substantially underwent oxidative modification by PHP,and OFGs were targetedly ***,approximately 21.5-fold MB adsorption capacity was achieved by PHP-modified biochar comparing with its parent *** evaluate the compatibility of PHP-modification,coefficient of variation(CV)based on MB adsorption capacity by the biochar from various precursors was calculated,in which the CV of PHP-modified biochars was 0.0038 comparing to0.64 of the corresponding parent *** results suggested that the PHP method displayed the excellent feedstock compatibility on biochar *** maximum MB adsorption capacity was454.1 mg/g when the H_(3)PO_(4)and H_(2)O_(2)fraction in PHP were 65.2%and 7.0%;the modification was further intensified by promoting temperature and ***,average 94.5%H_(3)PO_(4)was recovered after 10-batch modification,implying 1.0 kg H_(3)PO_(4)(85%)in PHP can maximally modify 2.37 kg ***,this work offered a novel method to tailor biochar towards OFGs-rich surface for efficient adsorption.

关键词： Biochar Oxidative modification Phosphoric acid Hydrogen peroxide Oxygenated functional groups

Hygrothermal effect on high-velocity impact resistance of woven composites

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Defence Technology（防务技术） 2022年第5期18卷 823-833页

作者： Xiao-chen Yang nan Jia School of Urban Construction Eastern Liaoning UniversityWenhua 325Dandong118003China College of Safety Science and Engineering Liaoning Technical UniversityFuxin123000China China Coal Technology&Engineering Group Shenyang Research Institute Fushun113122China State Key Laboratory of Coal Mine Safety Technology Fushun113122China

The woven glass fiber reinforced composites(GFRP)subjected to high-speed impact is investigated to identify the hygrothermal aging effect on the impact *** the hygrothermal aged and unaged glass/epoxy laminates are subjected to different impact velocities,which is confirmed as a sensitive factor for the failure modes and *** results show the hygrothermal aging effect decreases the ballistic limit by 14.9%,but the influence on ballistic performance is limited within the impact velocity closed to the ballistic *** failure modes and energy dissipation mechanisms are confirmed to be slightly influenced by the hygrothermal aging *** hygrothermal aging effect induced localization of structural deformation and degradation of mechanical properties are the main reasons for the composite undergoing the same failure modes at smaller impact *** on the energy absorption mechanisms,analytical expressions predict the ballistic limit and energy absorption to reasonable accuracy,the underestimated total energy absorption results in a relatively poor agreement between the measured and predicted energy absorption efficiency.

关键词： Hygrothermal aging effect Woven glass/epoxy composite Impact resistance Dynamic failure Energy absorption

Weighted Pseudo Asymptotically Periodic Mild Solutions of Evolution Equations

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Acta Mathematica Sinica,English Series 2015年第8期31卷 1215-1232页

作者： Zhi nan XIA Department of Applied Mathematics Zhejiang University of Technology

In this paper, we propose a new class of functions called weighted pseudo S-asymptotically periodic function in the Stepanov sense and explore its properties in Banach space including composition theorems. Furthermore, the existence, uniqueness of the weighted pseudo S-asymptotically periodic mild solutions to partial evolution equations and nonautonomous semilinear evolution equations are investigated. Some interesting examples are presented to illustrate the main findings.

关键词： Sp-weighted pseudo S-asymptotic periodicity weighted pseudo S-asymptotic periodicity evolution equations mild solutions

Black hole binaries and microquasars

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Frontiers of physics 2013年第6期8卷 630-660页

作者： Shuang-nan Zhang Laboratory for Particle Astrophysics Institute of High Energy Physics Beijing 100049 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

This is a general review Oil the observations and physics of black hole X-ray binaries and microquasars, with the emphasize on recent developments in the high energy regime. The focus is put on understanding the accretion flows and measuring the parameters of black holes in them. It includes mainly two parts： i） Brief review of several recent review article on this subject; ii） Further development on several topics, including black hole spin measurements, hot accretion flows, corona formation, state transitions and thermal stability of standard think disk. This is thus not a regular bottom-up approach, which I feel not necessary at this stage. Major effort is made in making and incorporating from many sources useful plots and illustrations, in order to make this article more comprehensible to non-expert readers. In the end I attempt to make a unification scheme on the accretion-outflow （wind/jet） connections of all types of aecreting BHs of all accretion rates and all BH mass scales, and finally provide a brief outlook.

关键词： accretion and accretion disks neutron stars black holes jets and bursts X-ray sources γ-ray sources X-ray binaries

基于深度神经网络的航空叶片表面缺陷检测算法

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光电子·激光 2025年第2期36卷 130-135页

作者：苏宝华张吟龙张男冯选中国航发沈阳黎明航空发动机有限责任公司产品检验检测中心中国科学院沈阳自动化研究所工业控制网络与系统研究室沈阳化工大学信息工程学院

航空叶片表面缺陷的准确检测是保证航空发动机安全可靠运转的关键。目前基于视觉的航空叶片表面缺陷检测算法存在实时性差、漏检率高、定位目标不准等问题。针对上述问题，本文提出一种基于深度神经网络的航空叶片表面缺陷检测算法。为... 详细信息

航空叶片表面缺陷的准确检测是保证航空发动机安全可靠运转的关键。目前基于视觉的航空叶片表面缺陷检测算法存在实时性差、漏检率高、定位目标不准等问题。针对上述问题，本文提出一种基于深度神经网络的航空叶片表面缺陷检测算法。为了提高检测实时性，本文设计了深度可分离卷积(depthwise separable convolution, DSC)模型分解标准卷积；为了降低小目标缺陷漏检，本文设计了SE-PAN (squeeze-and-excitation path aggregation network)模型对每个通道的特征进行重标定，使得具有更强信息的特征得到更多的关注；为了提高定位准确度，本文设计了Focal-DIOU (focal-distance intersection over union)损失函数减弱低效框的作用。在本文的航空叶片表面缺陷数据集上的实验证明：本文算法的Precision、Recall、AP达到了95.7%、94.6%、96.3%,检测帧率达到24帧/s,均优于主流检测算法。

关键词：缺陷检测深度神经网络损失函数注意力模型

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Systematic investigation of mid-term periodicity of the solar full-disk magnetic fields

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Research in Astronomy and Astrophysics 2019年第9期19卷 97-108页

作者： nan-Bin Xiang Yunnan Observatories Chinese Academy of Sciences CAS Key Laboratory of Solar Activity National Astronomical Observatories Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory

The Magnetic Plage Strength Index(MPSI) and the Mount Wilson Sunspot Index(MWSI), which have been measured at Mount Wilson Observatory(MWO) since the 1970 s and which indicate weak and strong magnetic field activity on the solar full disk, respectively, are used to systematically investigate midterm periodicities in the solar full-disk magnetic fields. Multitudinous mid-term periodicities are detected in MPSI and MWSI on timescales of 0.3 to 4.5 yr, and these periodicities are found to fluctuate around several typical periodicities within a small amplitude in different solar cycles or phases. The periodicity of 3.44 yr is found in MPSI, and the periodicities of 3.85 and 3.00 yr are detected in MWSI. Our analysis indicates that they reflect the true oscillating signals of solar magnetic field activity. The typical periodicities are 2.8,2.3 and 1.8 yr in MPSI and MWSI, and possible mechanisms for these periodicities are discussed. A 1.3 yr periodicity is only detected in MPSI, and should be related to meridional flows on the solar surface. The typical annual periodicity of MPSI and MWSI is 1.07 yr, which is not derived from the annual variation of Earth’s heliolatitude. Several periodicities shorter than 1 yr found in MPSI and MWSI are considered to be Rieger-type periodicities.

关键词： Sun:general Sun:activity Sun:magnetic fields

基于肠道菌群和广泛靶向代谢组学的山柰酚抗骨质疏松的作用机制

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中国组织工程研究 2025年第20期29卷 4190-4204页

作者：梁周张驰潘成镇杨博蒲张林刘桦彭金辉文立春凌观汉陈锋广西中医药大学广西壮族自治区南宁市530000 玉林市中西医结合骨科医院广西壮族自治区玉林市537599

背景:山柰酚具有抗骨质疏松的作用,但山柰酚通过调控肠道菌群、代谢物防治骨质疏松的作用机制尚不明确。目的:基于肠道菌群和广泛靶向代谢组学探究山柰酚抗骨质疏松的可能作用机制。方法:将雌性Sprague-Dawley大鼠18只随机分为假手术组... 详细信息

背景:山柰酚具有抗骨质疏松的作用,但山柰酚通过调控肠道菌群、代谢物防治骨质疏松的作用机制尚不明确。目的:基于肠道菌群和广泛靶向代谢组学探究山柰酚抗骨质疏松的可能作用机制。方法:将雌性Sprague-Dawley大鼠18只随机分为假手术组、模型组和山柰酚组,每组6只,后2组切除双侧卵巢制备骨质疏松大鼠模型。造模后8周,假手术组和模型组采用蒸馏水灌胃,山柰酚组采用40 mg/kg山柰酚灌胃,各组均连续给药12周。取大鼠粪便进行16SrDNA扩增子测序,观察肠道菌群结构的变化;采用超高效液相色谱-串联质谱技术、自主开发的数据库和多元统计分析的方法进行血清样本广泛靶向代谢组学检测。结果与结论:①连续干预12周后,16SrDNA扩增子测序结果显示,与假手术组相比,模型组肠道菌群丰度增加;与模型组相比,山柰酚组上调Latilactobacillus菌属(P=0.021)丰度,下调泛菌属(Pantoea)(P=0.034)、肠杆菌属(Enterorhabdus)(P=0.000)、Monoglobus菌属(P=0.024)、丁酸单胞菌属(Butyricimonas)(P=0.034)、Rothi属(P=0.043)、梭杆菌属(Clostridia)(P=0.004)等菌属丰度。②连续干预12周后,血清样本广泛靶向代谢组学检测结果显示,假手术组与模型组、模型组与山柰酚组之间分别鉴定出120和79种代谢物,3组间共有17种交集差异代谢物,包括乌头酸、巴比妥酸、L-高瓜氨酸、3,4,5-三甲氧基肉桂酸、L-3-苯基乳酸、环(脯氨酸-脯氨酸)、L-苯丙氨酸-L-丝氨酸、脯氨酸-异亮氨酸、L-冬胺基乙酸-L-苯丙胺基乙酸、苯丙氨酸-天冬氨酸等。大部分属于氨基酸及其代谢物、甘油磷脂类和脂肪酰类。差异代谢物涉及的KEGG通路主要富集在D-氨基酸代谢、组氨酸代谢、丙酸代谢、赖氨酸降解、脂肪酸代谢、鞘脂代谢等。③连续干预12周后,联合分析发现,肠杆菌属(Enterorhabdus)、Latilactobacillus属、Rothia属和瘤胃球菌属(Ruminococcus)等与血清差异代谢物密切相关。④山柰酚可能通过调节肠道菌群的丰度、多样性及结构,调控氨基酸及其代谢物的代谢、脂肪酸代谢等发挥抗骨质疏松的作用。

关键词：山柰酚骨质疏松肠道菌群 16SrDNA扩增子测序广泛靶向代谢组学超高效液相色谱-串联质谱作用机制大鼠

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