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Polymerized A-DA'D-A type small-molecule acceptors for high performance all-polymer solar cells: progress and perspective

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Science China Chemistry 2023年第9期66卷 2513-2531页

作者： ting yang Chuanlang Zhan Key Laboratory of Advanced Materials Chemistry and Devices(AMC&DLab)of the Department of Education of Inner Mongolia Autonomous Region College of Chemistry and Environmental ScienceInner Mongolia Normal UniversityHuhhot 010022China

A-DA'D-A type polymerized small-molecule acceptors(PSMAs) have very recently received wide attention because they possess advantages such as synthetic flexibility, narrowed bandgap, low energy loss, and impressive mechanical properties. With efforts on design and synthesis of PSMAs and polymer donors, significant progress has been made on all polymer solar cells(allPSCs) with power conversion efficiencies exceeding 18%. In this review, we focus on structure-property-performance relationships of the A-DA'D-A type PSMAs. First, we in-depth review the regio-random, regio-regular, and random ternary series by focusing on their structural modification such as from aspects of side-chains, halogenation, selenophene-containing and linkers, respectively. Second, we review the mechanically flexible and stretchable properties, which helps to find structural gene that correlates the mechanical properties. Third, we review the impressive small energy loss. In all, this review provides structural and material's clues, helpfully for designing high-performance all-PSCs.

关键词： all-polymer solar cell polymerized small-molecule acceptor regio-random regio-regular terpolymer energy loss

前期东北大西洋-地中海西部海温异常影响河南省干热风的可能途径

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高原气象 2025年第1期44卷 150-162页

作者：竹磊磊苏晓乐潘攀吴璐杨婷中国气象局•河南省农业气象保障与应用技术重点开放实验室河南郑州450003 河南省气候中心河南郑州450003

河南省是中国冬小麦的主产区,也是较易受干热风影响的地区。目前对干热风的研究和预报多在天气尺度,从气候的角度研究干热风是否具有可预报性,具有非常重要的意义。本文基于河南省干热风资料、NCEP/NCAR再分析资料和哈得莱环流中心海温... 详细信息

河南省是中国冬小麦的主产区,也是较易受干热风影响的地区。目前对干热风的研究和预报多在天气尺度,从气候的角度研究干热风是否具有可预报性,具有非常重要的意义。本文基于河南省干热风资料、NCEP/NCAR再分析资料和哈得莱环流中心海温资料,分析了1980-2022年前期海温异常与河南省干热风日数的关系,及其可能影响途径。结果表明:(1)豫北、豫西北和豫中多年平均干热风日数较多,其他地区则相对较少。日干热风出现的概率由南向北、由5月下旬至6月上旬逐渐增加。全省平均干热风日数有显著增加趋势。(2)河南省干热风日数与当年3-4月东北大西洋-地中海西部(关键区)海温在年代际和年际尺度上均存在着密切相关,两者与干热风发生时段500 hPa高度场在去趋势前和去趋势后的显著正相关区在东亚中纬度地区位于新疆北部至贝加尔湖尔湖北部,显著负相关区位于我国东北至日本群岛附近,与850 hPa风场在去趋势前和去趋势后的相关在上述正、负显著相关区分别呈反气旋和气旋分布,气旋后部呈偏北风的显著相关,即3-4月关键区高海温年,出现的蒙古高压脊和东亚大槽造成了河南省的干热风天气。海温与环流场的相关在去趋势前和去趋势后在中纬度地区呈现出一个更明显的由东北大西洋经欧亚大陆至东北亚的纬向遥相关波列。(3)西太平洋副热带高压(以下简称副高)偏南(北)时,干热风日数易偏多(少),而3-4月关键区高(低)海温则可以导致副高偏南(北)。(4)干热风偏多年和偏少年、3-4月关键区高海温年和低海温的干热风发生时段30°N-55°N经向平均的涡度差值,及高、低海温年的干热风发生时段500 hPa准地转流函数距平和波作用通量均显示在中纬度地区存在自东北大西洋至东北亚的纬向波列。也即表明,3-4月关键区海温可以激发出一个后期干热风发生时段的类似波列,经欧亚大陆传至东北亚,而高海温年在东亚中纬度地区的环流分布造成了河南省的干热风天气。

关键词：干热风东北大西洋地中海西部海温遥相关波列

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Microstructural evolution,tensile property and dynamic compressive property of FSWed Ti-6Al-4V alloy

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Rare Metals 2020年第2期39卷 169-175页

作者： Jia-Wei Bao Su-Yuan yang ting yang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China

Friction stir welding was applied to Ti-6 A1-4 V plates with 5 mm in *** microstructure and mechanical properties were investigated.A full lamellar microstructure was developed near the top surface,and the size of priorβgrain gradually decreases as the distance from the top surface *** microstructure of the bottom is fine equiaxed a grains,and the mean size is2μm.A mixture microstructure consisting of primary a,lamellarα+βand fine equiaxedαis discovered in thermomechanically affected zone(TMAZ).Results of transverse tensile test show that the tensile strength of the joint reaches 98%that of the base material(BM).Quasi-static compression test shows that the joint exhibits larger compressive strength and failure strain than the *** compressive strength of the joint is close to that of the BM;furthermore,the strain at the peak stress and energy absorption of the joint are larger than those of the BM.

关键词： Friction stir welding Ti-6Al-4V Microstructure Tensile property Dynamic compressive property

Permethrin resistance variation and susceptible reference line isolation in a field population of the mosquito, Culex quinquefasciatus （Diptera： Culicidae）

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Insect Science 2014年第5期21卷 659-666页

作者： ting yang Nannan Liu Department of Entomology and Plant Pathology Auburn University Auburn AL 36849 USA

This study examines the genetic variations and mechanisms involved in the development of permethrin resistance in individual mosquitoes from a field population of Culex quinquefasciatus, HAmCq^G0, and characterizes susceptible reference lines of mosquitoes with a similar genetic background to the field HAmCq^G0 strain. Six upregulated cytochrome P450 genes, CYP9M10, CYP9J34, CYP6P14, CYP9J40, CYP6AA7, and CYP4C52v1, previously identified as being upregulated in the larvae of resistant HAmCq68 mosquitoes were examined in the larvae of 3 strains （susceptible S-Lab, parental HAmCq^G0 and permethrin-selected highly resistant HAmCq68） and 8 HAmCq^G0 single- egg raft colonies, covering a range of levels of susceptibility/resistance to perrnethrin and exhibiting different variations in the expression of A and/or T alleles at the L-to-F kdr locus of the sodium channel. The 2 lines with the lowest tolerance to permethrin and bearing solely the susceptible A allele at the L-to-F kdr locus of the sodium channels, from colonies Cx_SERC5 and Cx_SERC8, showed lower or similar levels of all 6 of the P450 genes tested compared with the S-Lab strain, suggesting that these 2 lines could be used as the reference mosquitoes in future studies characterizing insecticide resistance in HAmCq mosquitoes. This study also provides a detailed investigation of the mechanisms involved in insecticide resistance in individuals within a population： individuals with elevated levels of resistance to permethrin all displayed one or more potential resistance mechanisms-either elevated levels of P450 gene expression, or L-to-F mutations in the sodium channel, or both.

关键词： Culex quinquefasciatus permethrin resistance single-egg raft colony susceptibility

CONVERGENCE PROPERTIES OF MULTI-DIRECTIONAL PARALLEL ALGORITHMS FOR UNCONSTRAINED MINIMIZATION

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Journal of Computational Mathematics 2005年第4期23卷 357-372页

作者： Cheng-xian Xu Yue-ting yang Faculty of Sciences Xi'an Jiaotong University Xi'an 710049 China

Convergence properties of a class of multi-directional parallel quasi-Newton algorithms for the solution of unconstrained minimization problems are studied in this paper. At each iteration these algorithms generate several different quasi-Newton directions, and then apply line searches to determine step lengths along each direction, simultaneously. The next iterate is obtained among these trail points by choosing the lowest point in the sense of function reductions. Different quasi-Newton updating formulas from the Broyden family are used to generate a main sequence of Hessian matrix approximations. Based on the BFGS and the modified BFGS updating formulas, the global and superlinear convergence results are proved. It is observed that all the quasi-Newton directions asymptotically approach the Newton direction in both direction and length when the iterate sequence converges to a local minimum of the objective function, and hence the result of superlinear convergence follows.

关键词： Unconstrained minimization Multi-directional parallel quasi-Newton method Global convergece Superlinear convergence

Improvement of a MIMO antenna structure with combination of transmit beamforming and spatial multiplexing

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 91-95页

作者： YUAN ting-ting ZHANG Lei yang Hong-wen yang Da-cheng School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Downlinks of the cellular systems generally have more transmit antennas than receive antennas. To efficiently exploit all antenna resources, a technique that combines the advantage of beamforming and spatial multiplexing has been proposed, which partitions the transmit antennas into neighboring sub-groups. In this article, this technique is further improved by Eq. （1） allowing non-contiguous antenna grouping, and Eq. （2） adopting two new grouping criteria： minimum signal distance maximization （MSDM） criterion and maximum correlation coefficient minimization （MCCM） criterion. Simulation results indicate that these improvements can bring noticeable gains in the Rayleigh fiat fading channel environment.

关键词： multiple-input multiple-output (MIMO) beamforming antenna grouping uncorrelated channel semi-correlated channel

A ferric citrate derived Fe-N-C electrocatalyst with stepwise pyrolysis for highly efficient oxygen reduction reaction

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Chinese Chemical Letters 2022年第1期33卷 362-367页

作者： Min Zhang Bolong yang ting yang Yahui yang Zhonghua Xiang State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081China

Unremitting and intensive researches about efficient non-precious metal electrocatalysts are necessary for large-scale commercial applications of fuel cells,while iron and nitrogen co-doped carbon(Fe-N-C)materials has become one of the most promising electrocatalysts to replace Pt-based noble metal ***,the traditional Fe-doped ZIF with rhomb dodecahedron morphology limits the exposure of active sites and the utilization of atoms,even affecting the performance of the ***,a Fe/N co-doped catalyst with a flower-like morphology was prepared using ferric citrate source along with secondary NH_(3)heat *** optimal catalyst(termed as 4Fe_(citrate)-N-C-3)showed distinguished oxygen reduction reaction(ORR)activity with a half-wave potential of 0.8 and 0.9 V(***)in acid and alkaline media,*** addition,4Fe_(citrate)-N-C-3 maintained more than 80%of original activity even after 50,000 s which is superior to the benchmark Pt/*** strategy of controlling morphology and composition is meaningful for the optimization of non-precious metal electrocatalysts for ORR in fuel cells or metal-air batteries.

关键词： Oxygen reduction reaction Non-precious metal electrocatalysts Fuel cell ZIF-8 NH3 activation

A Novel Customer-Oriented Recommendation System for Paid Knowledge Products

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Journal of Systems Science and Systems Engineering 2022年第5期31卷 515-533页

作者： ting yang Jilong Zhang Liye Wang Jin Zhang School of Business Renmin University of ChinaBeijing 100872China International Business School Bejing Foreign Studies UniversityBeijing 100089China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBejing 100024China School of Economics and Management Communication University of ChinaBeijing 100024China

With the rapid development of knowledge pal malto:wangliye@*** with a large number of knowledge products when purchasing,leading to the need for an effective recommendation ***,existing recommendation systems cannot accurately and adequately represent paid knowledge products with implicit but specialized features and sparse interactive histories,and thus are deemed not suitable for such *** this paper,we propose a novel recommendation system for knowledge products,the core of which is the designed customer oriented representation of knowledge ***,we utilize customer activity information on the free knowledge sharing platform as the knowl-edge document for each customer of paid knowledge products,to extract customer knowledge background and ***,a deep learning based model Doc2vec is adopted to transfer knowledge documents to customer knowledge background *** vectors of a particular paid knowledge product are further aggregated to a product-level vector for customer-oriented product representation,based on which two recommendation results are generated with product ratings and similarities of paid knowledge prod-ucts,*** comparative experiments are conducted to demonstrate the ffectiveness of the proposed system for the representation and recommendation of paid knowledge *** paper will contribute to the literature of knowledge payment and recommendation systems,as well as provide practical implications for the information service and the operation of knowledge products on knowledge payment platforms.

关键词： Recommendation system knowledge product knowledge payment Doc2vec product repre-sentation

Drivers of microbial beta-diversity in wastewater treatment plants in China

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Journal of Environmental Sciences 2022年第5期34卷 341-349页

作者： Bing Zhang ting yang Chenxiang Sun Xianghua Wen College of Life and Environmental Sciences Minzu University of ChinaBeijing 100081China Environmental Simulation and Pollution Control State Key Joint Laboratory School of EnvironmentTsinghua UniversityBeijing 100084China

As one of the most well-documented biogeographic patterns,the distance-decay relation-ship provides insights into the underlying mechanisms driving biodiversity ***-though wastewater treatment plants(WWTPs)are well-controlled engineered ecosystems,this pattern has been seen among microbial communities in activated sludge(AS).However,little is known about the relative importance of environmental heterogeneity and dispersal limitation in shaping AS microbial community across China;especially they are related to spatial scale and organism ***,we assessed the distance-decay relationship based on different spatial scales and microbial phylogenetic groups by analyzing 132 activated sludge(AS)samples across China comprising 3,379,20016S rRNA *** results in-dicated that the drivers of distance-decay pattern in China were *** biogeographic patterns in WWTPs were mainly driven by dispersal limitation at both local and national *** contrast,conductivity,SRT,and pH played dominant roles in shaping AS microbial community compositions at the regional *** rates and the drivers of beta-diversity also varied with microorganism ***,a quantitative re-lationship between dispersal limitation ratio and AS microbial turnover rate was ***,these results highlighted the importance of considering multiple spatial scales and micro-organism types for understanding microbial biogeography in WWTPs and pro-vided new insights into predicting variations in AS community structure in response to environmental disturbance.

关键词： Wastewater treatment plant Distance-decay pattern Scale-dependent Microbial assembly Dispersal limitation