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Ca and Sr co-doping induced oxygen vacancies in 3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts for boosting low-temperature oxidative coupling of methane

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Journal of Energy Chemistry 2024年第4期91卷 331-344页

作者： Tongtong Wu Yuechang Wei Jing Xiong Yitao Yang Zhenpeng Wang dawei Han Zhen Zhao jian Liu State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Key Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing 102249China

It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower ***,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active *** co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,*** mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature *** is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application.

关键词： 3DOM catalysts Ca ions Sr ions Low-temperature oxidative couplingof methane Oxygen vacancies O_(2)^(-) species

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Ultrahigh-fidelity spatial mode quantum gates in high-dimensional space by diffractive deep neural networks

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Light(Science & Applications) 2024年第1期13卷 55-67页

作者： Qianke Wang Jun Liu dawei Lyu jian Wang Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan430074HubeiChina Optics Valley Laboratory Wuhan430074HubeiChina

While the spatial mode of photons is widely used in quantum cryptography, its potential for quantum computation remains largely unexplored. Here, we showcase the use of the multi-dimensional spatial mode of photons to construct a series of high-dimensional quantum gates, achieved through the use of diffractive deep neural networks (D2NNs). Notably, our gates demonstrate high fidelity of up to 99.6(2)%, as characterized by quantum process tomography. Our experimental implementation of these gates involves a programmable array of phase layers in a compact and scalable device, capable of performing complex operations or even quantum circuits. We also demonstrate the efficacy of the D2NN gates by successfully implementing the Deutsch algorithm and propose an intelligent deployment protocol that involves self-configuration and self-optimization. Moreover, we conduct a comparative analysis of the D2NN gate’s performance to the wave-front matching approach. Overall, our work opens a door for designing specific quantum gates using deep learning, with the potential for reliable execution of quantum computation.

关键词： quantum dimensional operations

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Plant virology in the 21st century in China:Recent advances and future directions

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Journal of Integrative Plant Biology 2024年第3期66卷 579-622页

作者： jianguo Wu Yongliang Zhang Fangfang Li Xiaoming Zhang jian Ye Taiyun Wei Zhenghe Li Xiaorong Tao Feng Cui Xianbing Wang Lili Zhang Fei Yan Shifang Li Yule Liu dawei Li Xueping Zhou Yi Li State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops Vector-borne Virus Research CenterCollege of Plant ProtectionFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Plant Environmental Resilience and Ministry of Agriculture Key Laboratory of Soil Microbiology College of Biological SciencesChina Agricultural UniversityBeijing 100193China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Rice Biology Institute of BiotechnologyZhejiang UniversityHangzhou 310058China Department of Plant Pathology The Key Laboratory of Plant ImmunityNanjing Agricultural UniversityNanjing 210095China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Plant VirologyNingbo UniversityNingbo 315211China MOE Key Laboratory of Bioinformatics Center for Plant BiologySchool of Life SciencesTsinghua UniversityBeijing 100084China State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China

Plant viruses are a group of intracellular pathogens that persistently threaten global food *** advances in plant virology have been achieved by Chinese scientists over the last 20 years,including basic research and technologies for preventing and controlling plant viral ***,we review these milestones and advances,including the identification of new crop-infecting viruses,dissection of pathogenic mechanisms of multiple viruses,examination of multilayered interactions among viruses,their host plants,and virus-transmitting arthropod vectors,and in-depth interrogation of plantencoded resistance and susceptibility ***,various plant virus-based vectors have also been successfully developed for gene function studies and target gene expression in *** also recommend future plant virology studies in China.

关键词： China emerging plant viruses plant virology plant resistance/susceptibility to viral infection plant-virus transmission vector interactions plant virus-based vectors viral pathogenesis

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Variation in allelic frequencies at loci associated with kernel weight and their effects on kernel weight-related traits in winter wheat

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The Crop Journal 2019年第1期7卷 30-37页

作者： Teng Li Hongwei Liu Chunyan Mai Guangjun Yu Huili Li Lingzhi Meng dawei jian Li Yang Yang Zhou Hongjun Zhang Hongjie Li National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop Sciences Chinese Academy of Agricultural Sciences Xinxiang Innovation Center for Breeding Technology of Dwarf-Male-Sterile Wheat Zhaoxian Experiment Station Shijiazhuang Academy of Agricultural and Forestry Sciences Institute of Agricultural Science The Fourth Division of the Xinjiang Production and Construction Corps

Knowledge of allelic frequencies at loci associated with kernel weight and effects on kernel weight-related traits is crucial for yield improvement in wheat. Kernel weight-related traits were evaluated in 200 Chinese winter wheat cultivars(lines) grown at the Xinxiang Experimental Station, Chinese Academy of Agricultural Sciences, Xinxiang in Henan Province, for three consecutive years from 2014 to 2016. Alleles associated with kernel weight at nine loci, TaCKX6-D1, TaCwi-A1, TaCWI-4A, TaGS1a, TaGS5-A1, TaGS3-3A, TaGW2-6A, TaSus2-2B, and TaTGW6-A1, were determined for all cultivars(lines). ANOVA showed that genotypes, years and their interactions had significant effects on thousand-kernel weight(TKW), kernel length(KL) and kernel width(KW). The overall mean frequencies of alleles conferring high and low TKW at the nine loci were 65.9% and 33.4%, with the ranges of 37.0%–85.0% and 13.5%–63.0% for single loci. The frequencies of high-TKW alleles were over 50.0% at eight of the loci. Genotypes at each locus with the high-TKW allele had higher TKW than those with the low-TKW allele. The high-TKW allele Hap-H at the TaSus2-2B locus can be preferably used to increase grain yield due to its high TKW(49.32 g). A total of 18 main allelic combinations(ACs) at nine loci were detected. Three ACs(AC1–AC3) had significantly higher TKW than AC6 with high-TKW alleles at all nine loci even though they contained some low-TKW alleles. This indicated that other loci controlling kernel weight were present in the high-TKW cultivars. This work provides important information for parental selection and marker-assisted selection for breeding.

关键词： Allelic frequency Allelic variation Functional markers Triticum aestivum

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Recent advances in Fe-N-C single-atom site coupled synergistic catalysts for boosting oxygen reduction reaction

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Electron 2024年第1期2卷 1-38页

作者： Katam Srinivas jian Zhen Hesheng Yu dawei Liu jian Zhen Ou Ming‐qiang Zhu Yuanfu Chen School of Integrated Circuit Science and Engineering and State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengduSichuanChina College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingChina School of Engineering RMIT UniversityMelbourneVictoriaAustralia

Metal-air batteries,fuel cells,and electrochemical H_(2)O2 production currently attract substantial consideration in the energy sector owing to their efficiency and ***,their broader use is hindered by the complex oxygen reduction reaction(ORR)that occurs at cathodes and involves intricate electron *** the significant ORR performance of platinum-based catalysts,their high cost,operational limitations,and susceptibility to methanol poisoning hinder broader *** emphasizes the need for efficient nonprecious metal-based ORR electrocatalysts.A promising approach involves utilizing single-atom catalysts(SACs)featuring metal-nitrogen-carbon(M-N-C)coordination *** offer advantages such as optimal utilization of metal atoms,uniform active centers,precisely defined catalytic sites,and robust metal-support ***,the symmetrical electron distribution around the central metal atom of a single-atom site(M-N4)often results in suboptimal ORR *** challenge can be addressed by carefully tailoring the surrounding environment of the active *** review specifically focuses on recent advancements in the Fe-N4 environment within Fe-N-C *** highlights the promising strategy of coupling Fe-N4 sites with metal clusters and/or nanoparticles,which enhances intrinsic *** capitalizing on the interplay between Fe-N4 sites and associated species,overall ORR performance *** review combines findings from experimental studies and density functional theory simulations,covering synthesis strategies for Fe-N-C coupled synergistic catalysts,characterization techniques,and the influence of associated particles on ORR *** offering a comprehensive outlook,the review aims to encourage research into high-efficiency Fe single-atom sites coupled synergistic catalysts for real-world applications in the coming years.

关键词： electrocatalysis oxygen reduction reaction particle@Fe-N-C single-atom catalysts synergistic catalysts

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高速高功率密度无轴承永磁薄片电机设计与优化

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电机与控制学报 2024年第6期28卷 171-180页

作者：李健陈红李大伟裴同豪刘嘉韵山东科技大学电气与自动化工程学院山东青岛266590 华中科技大学电气与电子工程学院湖北武汉430074

传统无轴承电机在高速和高功率密度之间难以取得平衡,为此围绕高速高功率密度无轴承永磁薄片电机,对其拓扑结构、绕组形式、主要尺寸等方面进行优化设计,在保证转速和功率密度的基础上有效地提升悬浮性能。通过对运行工况的分析,得出电... 详细信息

传统无轴承电机在高速和高功率密度之间难以取得平衡,为此围绕高速高功率密度无轴承永磁薄片电机,对其拓扑结构、绕组形式、主要尺寸等方面进行优化设计,在保证转速和功率密度的基础上有效地提升悬浮性能。通过对运行工况的分析,得出电机拓扑结构需具备的基本特点,提出一种采用环形集成绕组的表贴式无轴承永磁薄片电机。在兼顾转矩和悬浮力输出性能、机械防护可靠性的基础上,对电机的电磁气隙长度和永磁体参数等主要尺寸进行优化设计。针对电机饱和、绕组端部伸出等不利因素,分别采取了超前角弱磁、定子略长的性能提升策略,有效地避免了悬浮力的大幅度跌落。搭建20 000 r/min的无轴承永磁薄片电机有限元仿真模型并制造实物样机。通过对电磁转矩和主、被动悬浮力的分析,证明了本文设计的无轴承永磁薄片电机兼具良好的转矩与悬浮力输出性能,单位幅值电流产生的电磁转矩、主动悬浮力分别为0.166 N·m、4.4 N,电机输出功率10 kW、功率密度5.2 kW/kg。

关键词：无轴承永磁薄片电机高速高功率密度环形绕组优化设计弱磁控制端部效应

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Na_(2)CO_(3)-Na_(2)SO_(4)复盐熔炼法从碱溶渣中高效分离钨的工艺研究

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中国有色金属学报 2024年第2期34卷 529-536页

作者：冯浩郭学益许开华于大伟黄健何鑫涛中南大学冶金与环境学院长沙410083 荆门市格林美新材料有限公司荆门448000

钨合金废料资源化利用过程中容易产生含钨碱溶渣,且该部分含钨碱溶渣中钨品位较高。本文开发了一种复盐(Na_(2)CO_(3)-Na_(2)SO_(4))熔炼工艺,以对含钨碱溶渣中的钨进行高效分离;探究Na_(2)CO_(3)和Na_(2)SO_(4)的添加量、复盐熔炼温度... 详细信息

钨合金废料资源化利用过程中容易产生含钨碱溶渣,且该部分含钨碱溶渣中钨品位较高。本文开发了一种复盐(Na_(2)CO_(3)-Na_(2)SO_(4))熔炼工艺,以对含钨碱溶渣中的钨进行高效分离;探究Na_(2)CO_(3)和Na_(2)SO_(4)的添加量、复盐熔炼温度、熔炼时间以及水浸液固比、水浸温度对钨回收率的影响。结果表明:从含钨碱溶渣中高效分离钨的最优条件为n(W)∶n(Na_(2)CO_(3))∶n(Na_(2)SO_(4))=1∶1.25∶0.54,复盐熔炼温度为800℃,熔炼时间为3 h,水浸液固比为2.5,水浸温度为75℃,在该最优条件下可将含钨碱溶渣中99.93%的钨分离出来。同时,本文通过XRD分析以及热力学分析对复盐熔炼的反应机理进行了探讨,复盐体系的构建有助于降低体系共熔点,降低能耗,同时有助于促进碱溶渣与反应介质的充分接触,提高反应效率。

关键词：钨合金废料含钨碱溶渣复盐熔炼热力学

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统筹治理下的多元供给:上海市区级老年人体育协会服务供给效率研究

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体育科学 2024年第2期44卷 12-23页

作者：康健陈晓峰张大为浙江师范大学体育与健康科学学院浙江金华321004 上海商学院体育与健康系上海200235 山西师范大学体育学院山西临汾030031

优化老年人体育协会的服务供给效率,是落实全民健身战略和积极应对人口老龄化战略的必然要求。选用数据包络分析法中的非期望产出超效率模型,测算上海市各区级老年人体育协会的服务供给效率,依照“分类别、作比较、找议题”的总体思路,... 详细信息

优化老年人体育协会的服务供给效率,是落实全民健身战略和积极应对人口老龄化战略的必然要求。选用数据包络分析法中的非期望产出超效率模型,测算上海市各区级老年人体育协会的服务供给效率,依照“分类别、作比较、找议题”的总体思路,对比和分析不同类型的区级老年人体育协会服务的供给效率。研究表明,1)上海市区级老年人体育协会服务呈现统筹治理下的多元供给特征。其中,统筹治理既体现在各区级老年人体育协会在市级协会和政府部门领导下统一老年体育服务的服务类型、内容标准、供给路径,也体现在治理主体、治理环境和治理资源的协调统筹方面;多元供给则体现为各区级老年人体育协会在服务供给效率、影响因素和应对策略的多元化。2)上海市各区级老年人体育协会服务供给可分为4类,即高效型、潜力型、待优化型和待发展型。3)在服务场域方面,城镇化场域与乡村性场域的服务供给效率差异,反映了公共服务均等化与老年体育需求个性化之间的矛盾。4)在政社关系方面,依附型与独立型的服务供给效率差异源于本区体育行政部门的组织结构,即前者体育行政部门的组织结构更为扁平,而后者组织层级更为庞杂。5)在资源整合方面,纵向一体化与横向一体化的服务供给效率差异源于各区的老年体育资源禀赋特征。具备禀赋优势的区通常采用纵向一体化的资源协调策略,禀赋优势不明显则更可能选择横向一体化的资源协调策略。

关键词：服务供给效率数据包络分析上海老年人体育协会

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神经营养因子3经受体切换促进大鼠脊髓损伤后神经功能的恢复

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中国组织工程研究 2025年第11期29卷 2268-2276页

作者：丛岩于健孙志德康大伟承德医学院附属医院急诊科河北省承德市067000

背景:神经营养因子是治疗脊髓损伤的新方法,调控自噬是其发挥作用的机制之一,但具体的信号通路尚不明确。目的:探讨神经营养因子3如何通过P75NTR/Trk C受体切换来调节少突胶质细胞的自噬以及促进脊髓损伤后神经功能恢复的作用,进一步明... 详细信息

背景:神经营养因子是治疗脊髓损伤的新方法,调控自噬是其发挥作用的机制之一,但具体的信号通路尚不明确。目的:探讨神经营养因子3如何通过P75NTR/Trk C受体切换来调节少突胶质细胞的自噬以及促进脊髓损伤后神经功能恢复的作用,进一步明确具体的分子机制。方法:将24只SD大鼠随机分为3组:假手术组、脊髓损伤组和神经营养因子3组,通过大鼠后肢神经功能评分来评估神经营养因子3对脊髓损伤大鼠的治疗效果,采用Western blot检测各组大鼠脊髓组织中神经营养因子3、Olig1、MBP蛋白以及自噬标记蛋白LC3B的表达水平。在细胞实验中,将少突胶质细胞接种在培养皿中,分为糖氧剥夺组、糖氧剥夺+神经营养因子3组、糖氧剥夺+神经营养因子3+P75NTR质粒组、糖氧剥夺+神经营养因子3+Trk C质粒组、糖氧剥夺+3-甲基腺嘌呤(自噬抑制剂)组及糖氧剥夺+雷帕霉素(自噬激活剂)组。光学显微镜观察少突胶质细胞形态变化,TUNEL染色观察细胞凋亡现象,Western blot检测Trk C受体、P75NTR、LC3B表达及PI3K/AKT/m TOR和AMPK/m TOR信号途径的磷酸化状态。结果与结论:(1)动物实验显示,与假手术组相比,脊髓损伤后神经营养因子3的表达显著增加(P<0.05);与脊髓损伤组相比,外源性神经营养因子3治疗能够加快大鼠神经功能的恢复(P<0.05),并增加Olig1和MBP蛋白的表达(P<0.05);(2)细胞实验发现,3 h是损伤早期与中后期的分界点,与糖氧剥夺组相比,糖氧剥夺+神经营养因子3组少突胶质细胞能够更长时间地维持其形态,Trk C受体在早期表达水平较低而中后期显著上调(P<0.05),P75NTR则在早期上调而中后期下调(P<0.05),自噬水平呈现出先升高后降低的趋势(P<0.05);(3)通过对比糖氧剥夺+神经营养因子3组、糖氧剥夺+雷帕霉素组和糖氧剥夺+3-甲基腺嘌呤组的细胞形态和TUNEL染色结果,发现单独促进或抑制自噬对少突胶质细胞的存活均有不利影响,而类似神经营养因子3这样调节自噬的方法则能最大限度地维持细胞存活;(4)神经营养因子3在早期通过P75NTR/AMPK/m TOR信号通路促进自噬,而在后期通过Trk C/PI3K/AKT/m TOR信号通路抑制自噬。根据上述结果,得到如下结论,即神经营养因子3可以通过P75NTR/Trk C受体的切换能够双向调控少突胶质细胞的自噬,从而维持细胞存活,有助于脊髓损伤后大鼠的神经功能恢复。

关键词：神经营养因子3 自噬少突胶质细胞受体切换凋亡脊髓损伤

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内孔式旋转空化器参数对空化效果的影响

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哈尔滨理工大学学报 2024年第1期29卷 44-49页

作者：韩桂华朱宜鹏洪健李大尉哈尔滨理工大学机械动力工程学院哈尔滨150080 黑龙江省科学院高技术研究院哈尔滨150020

通过控制变量法使用Fluent软件对内孔式旋转空化器进行数值模拟,得到结构参数(盲孔的孔径、孔深,单排盲孔个数)和操作参数(转速、入口压力)对空化效果的影响规律:转子盲孔孔径、孔深、单排盲孔个数增加,转速(2000~3000 r/min)增加,则盲... 详细信息

通过控制变量法使用Fluent软件对内孔式旋转空化器进行数值模拟,得到结构参数(盲孔的孔径、孔深,单排盲孔个数)和操作参数(转速、入口压力)对空化效果的影响规律:转子盲孔孔径、孔深、单排盲孔个数增加,转速(2000~3000 r/min)增加,则盲孔中气体体积增加;入口压力(1 MPa~4 MPa)增加,则盲孔中气体体积减小。实验中以纯水水样空化过程中温升和电导率的变化为空化效果检验标准,在3000~9000 r/min随着转速的增加,温升和电导率显著增加,间接验证数值模拟的结果。本文为内孔式旋转空化器的结构参数优化提供参考。

关键词：内孔式旋转空化器空化器参数空化效果影响规律

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