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National Science Review 2020年第11期7卷 1726-1742页

作者： peng peng Xiong-Hou Gao zi-Feng Yan Svetlana Mintova State Key Laboratory of Heavy Oil Processing China University of Petroleum Laboratory of Catalysis and Spectrochemistry (LCS) Normandy University National Graduate School of Engineering of Caen (ENSICAEN)University of Caen (UNICAEN) French National Center for Scientific Research (CNRS) Petrochemical Research Institute China National Petroleum Company

The preparation of hierarchical zeolites with reduced diffusion limitation and enhanced catalyst efficiency has become a vital focus in the field of zeolites and porous materials chemistry within the past decades. This review will focus on the diffusion and catalyst efficiency of hierarchical zeolites and industrial catalysts. The benefits of diffusion and catalyst efficiency at two levels of hierarchies (zeolitic component level and industrial catalyst level) from a chemical reaction engineering point of view will be analysed. At zeolitic component level, three types of mesopores based on the strategies applied toward enhancing the catalyst effectiveness factor are presented:(i)‘functional mesopores’(raising effective diffusivity);(ii)‘auxiliary mesopores’(decreasing diffusion length); and (iii)‘integrated mesopores’(a combination thereof). At industrial catalyst level, location and interconnectivity among the constitutive components are *** hierarchical pore interconnectivity in multi-component zeolite based industrial catalysts is exemplified by fluid catalytic cracking and bi-functional hydroisomerization catalysts. The rational design of industrial zeolite catalysts at both hierarchical zeolitic component and catalyst body levels can be fully comprehended using the advanced in situ and/or operando spectroscopic, microscopic and diffraction techniques.

关键词： diffusion effectiveness factor pore connectivity hierarchical zeolite industrial catalyst advanced characterization

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骆驼布鲁氏菌活疫苗A19株免疫试验

动物医学进展 2024年第5期45卷 137-139页

作者：高静周峰彭程胥元鹏王子坚聂龙祁张建春热孜婉南金鱼陈学生王新强甘肃省动物疫病预防控制中心甘肃兰州730046 阿克塞县畜牧兽医技术服务中心甘肃阿克塞736400 酒泉市畜牧兽医总站甘肃酒泉735000

为通过骆驼布鲁氏菌A19株疫苗免疫试验筛选出适宜的免疫方案,选择布鲁氏菌抗体检测阴性骆驼60头,按照不同剂量、不同年龄分4组颈部皮下注射免疫,并于免疫后不同时间采样检测免疫抗体。结果显示,1~3岁骆驼标准剂量(6×10^(10)CFU/头)免疫... 详细信息

为通过骆驼布鲁氏菌A19株疫苗免疫试验筛选出适宜的免疫方案,选择布鲁氏菌抗体检测阴性骆驼60头,按照不同剂量、不同年龄分4组颈部皮下注射免疫,并于免疫后不同时间采样检测免疫抗体。结果显示,1~3岁骆驼标准剂量(6×10^(10)CFU/头)免疫后23 d,免疫抗体阳性率为100%,至免疫12个月,免疫抗体阳性率0;1~3岁骆驼减低剂量(1×10^(9)CFU/头)免疫23 d,免疫抗体阳性率为94.1%,至免疫6个月,免疫抗体阳性率为0。3~12月龄骆驼标准剂量免疫38 d,免疫抗体阳性率为50%,免疫6个月,免疫抗体阳性率0。3~12月龄骆驼减低剂量免疫38 d,免疫抗体阳性率为16.7%,免疫6个月,免疫抗体阳性率为0。结果表明,1~3岁骆驼使用布氏菌活疫苗(A19株)标准剂量(6×10^(10)CFU/头)皮下注射免疫,效果最好。

关键词：骆驼布鲁氏菌活疫苗A19株免疫试验

基于深度学习的构音障碍人群语音事件识别模型

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电脑与信息技术 2024年第1期32卷 1-3页

作者：杨熠张子鹏中国矿业大学孙越崎学院江苏徐州221008

构音障碍是许多患有特殊疾病的患者所要面对的问题,会造成说话人发音不清晰。为更好地理解构音障碍患者所表达的语音事件,文章提出了一个新的基于深度学习的语音事件识别模型。模型以语音片段作为输入,运用格拉姆角场保留了时间序列的... 详细信息

构音障碍是许多患有特殊疾病的患者所要面对的问题,会造成说话人发音不清晰。为更好地理解构音障碍患者所表达的语音事件,文章提出了一个新的基于深度学习的语音事件识别模型。模型以语音片段作为输入,运用格拉姆角场保留了时间序列的原始特征,利用Conformer对序列的局部特征和全局特征进行提取,最后用Res Net作为分类模型。在EasyCall corpus数据集上的实验结果表明,文章提出的模型具有良好的识别效果。

关键词：语音事件识别格拉姆角场 Conformer ResNet

Preparation and properties of hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders

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Rare Metals 2021年第8期40卷 2033-2039页

作者： peng Zhao Yang Luo Dun-Bo Yu Hai-Jun peng Wen-Long Yan zi-Long wang Xin-Yuan Bai National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing100088China Grirem Advanced Materials Co. LtdBeijing100088China

The hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders were preparedunderdifferenthot-pressingtemperatures(600-750℃,at intervals of 25℃)by the self-made hotpressing *** microstructure and magnetic properties of hot-deformed magnets prepared at different temperatures were also *** the temperature is above 650℃,the density of magnet reaches 7.5 g·cm^(-3).The optimum magnetic properties of magnetic induction intensity of B_(r)=1.3 T,optimum energy product of(BH)_(max)=282.5 kJ·m^(-3),intrinsiccoercivityof H_(cj)=1130.0 kA·m-1 of hot-deformed magnets are obtained at hot-pressing temperature of 650℃.X-ray diffractometer pattern shows that the(00 L)texture has been *** the microstructural characteristic,on the one hand,the good magnetic performance is attributed to the fine platelet-like grains with an average length of 410-440 nm at the hot-pressing temperature range from625 to 675℃.On the other hand,the unaligned coarse grains are observed in all the *** the areal fraction of those is gradually increasing with the rise of the hot-pressing temperature,which tends to deteriorate the magnetic *** composition map shows the accumulation of Nd/Pr-rich phase in the coarse grains’region.

关键词： Nanocrystalline/amorphous powders Hotpressing temperature Hot-deformed Magnets Magnetic properties Microstructure

RNA解旋酶DDX5:细菌性炎症反应的调节器

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中国兽医科学 2024年第6期54卷 852-852页

作者： Jian Xu Li-Yuan Liu Fei-Jie Zhi Yin-Juan Song zi-Hui Zhang Bin Li Fu-Ying Zheng peng-Cheng Gao Su-zi Zhang Yu-Yu Zhang Ying Zhang Ying Qiu Bo Jiang Yong-Qing Li Chen peng Yue-Feng Chu State Key Laboratory for Animal Disease Control and Prevention College of Veterinary Medicine Lanzhou University Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Lanzhou China. National Key Laboratory of Veterinary Public Health College of Veterinary Medicine China Agricultural University Beijing China. College of Veterinary Medicine Xinjiang Agricultural University Urumqi China. State Key Laboratory of Cell Biology Shanghai Institute of Biochemistry and Cell Biology Center for Excellence in Molecular Cell Science Chinese Academy of Sciences University of Chinese Academy of Sciences Shanghai China. Institute of Animal Husbandry and Veterinary Medicine Beijing Academy of Agriculture and Forestry Sciences Beijing China. National Key Laboratory of Veterinary Public Health College of Veterinary Medicine China Agricultural University Beijing China. pengchenea@***. State Key Laboratory for Animal Disease Control and Prevention College of Veterinary Medicine Lanzhou University Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Lanzhou China. chuyuefeng@***.

细菌性感染是威胁动物和人类健康的重要原因之一,国际著名医学杂志《柳叶刀》发表的一项研究表明,金黄色葡萄球菌、大肠杆菌、肺炎链球菌、支原体等33种常见细菌感染是2019年全球人类第二大死亡原因,与全球八分之一的死亡有关,减少细菌... 详细信息

细菌性感染是威胁动物和人类健康的重要原因之一,国际著名医学杂志《柳叶刀》发表的一项研究表明,金黄色葡萄球菌、大肠杆菌、肺炎链球菌、支原体等33种常见细菌感染是2019年全球人类第二大死亡原因,与全球八分之一的死亡有关,减少细菌感染已成为全球公共卫生的优先事项。研制细菌感染防控技术和制定有效防控策略,离不开对细菌致病和免疫机制的深度解析。病原菌与宿主间存在双向、动态、复杂的相互作用,其中甲基化、泛素化等表观遗传修饰在病原菌与宿主互作的过程中发挥了重要作用.

关键词：细菌感染防控技术细菌性感染免疫机制肺炎链球菌防控策略金黄色葡萄球菌 RNA解旋酶

Soft X-ray ptychography method at SSRF

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Nuclear Science and Techniques 2017年第6期28卷 86-94页

作者： Chun-peng wang zi-Jian Xu Hai-Gang Liu Xulei Tao Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

Ptychography is a diffraction-based X-ray microscopy technique in which an extended sample is scanned by a coherent beam with overlapped illuminated areas and complex transmission function of the sample is obtained by applying iterative phase retrieval algorithms to the diffraction patterns recorded at each scanned *** permits quantitatively imaging of non-crystalline specimens at a resolution limited only by the X-ray wavelength and the maximal scattering angle *** this paper,the development of soft X-ray ptychography method at the BL08U1 A beamline of Shanghai Synchrotron Radiation Facility is *** experimental setup,experimental parameters selection criteria,and post-experimental data analyzing procedures are presented in detail with a prospect of high-resolution image reconstruction in real *** performance of this newly implemented method is demonstrated through the measurements of a resolution test pattern and two real samples:Pt-Co alloy nanoparticles and a breast cancer *** results indicate that strong scattering specimens can be reconstructed to sub-20 nm resolution,while a sub-25 nm resolution for biological specimens can be achieved.

关键词： Ptychography Coherent diffraction imaging X-ray microscopy Phase retrieval

槲皮素通过雌激素受体下调长非编码RNA MALAT-1并发挥抗乳腺癌的作用机制

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中国药理学通报 2024年第3期40卷 499-505页

作者：赵梓亦熊小明谢雨鹏张义文张翠薇成都中医药大学附属医院中医药调节代谢性疾病四川省重点实验室四川成都610000 西南医科大学附属医院病理科四川泸州646000 重大疾病精准病理诊断泸州市重点实验室四川泸州646000 西南医科大学临床医学院四川泸州646000 四川大学华西医院生物治疗全国重点实验室四川成都610041

目的探索槲皮素抑制乳腺癌细胞恶性生物学行为的分子机制。方法以乳腺癌细胞系MCF-7和MB231作为研究对象,用慢病毒LV-ERα、LV-MALAT-1转染乳腺癌MB231细胞和MCF7细胞,RT-qPCR检测MALAT-1表达,Western blot检测肿瘤细胞中ERα蛋白表达,C... 详细信息

目的探索槲皮素抑制乳腺癌细胞恶性生物学行为的分子机制。方法以乳腺癌细胞系MCF-7和MB231作为研究对象,用慢病毒LV-ERα、LV-MALAT-1转染乳腺癌MB231细胞和MCF7细胞,RT-qPCR检测MALAT-1表达,Western blot检测肿瘤细胞中ERα蛋白表达,CCK-8细胞实验、平板克隆形成实验检测细胞增殖能力,PI染色法检测细胞周期,通过mRFP-GFP-LC3荧光双标腺病毒转染检测自噬水平,观察槲皮素和雌二醇对乳腺癌细胞增殖能力的影响。结果17β-雌二醇(E2)可以促进乳腺癌细胞MCF-7的增殖,而5μmol·L^(-1)槲皮素可以明显逆转E2对增殖的促进作用(P<0.05)。槲皮素对不表达雌激素受体α(estrogen receptor-α,ERα)的乳腺癌细胞MB231不表现抑制作用;而过表达ERα后,槲皮素则抑制了E2对MB231-ERα的促进作用。同时槲皮素可以抑制E2激活的MALAT-1表达;并且其抑制作用被过表达MALAT-1所逆转,包括细胞增殖,细胞周期进展以及克隆形成能力。结论槲皮素依赖于ERα的表达对乳腺癌的增殖等恶性行为起抑制作用,并且很可能是通过抑制MALAT-1的表达来发挥作用。

关键词：乳腺癌槲皮素 17β-雌二醇雌激素受体 MALAT-1 细胞增殖

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共享服务者特性对消费者价值共创行为的影响

经济管理 2024年第5期46卷 130-148页

作者：涂科杨学成张冀新彭梓聪湖北数字工业经济发展研究中心湖北武汉430068 湖北工业研究院湖北武汉430068 湖北工业大学经济与管理学院湖北武汉430068 北京邮电大学经济管理学院北京100876

共享经济平台的兴起使越来越多的普通个体能够利用闲置资源为消费者提供服务,成为共享服务者。然而,学术界对共享服务者的特性及其对消费者价值共创行为的影响尚缺乏深入探讨。本文通过理论分析将共享服务者特性归纳为社交性与自主性,... 详细信息

共享经济平台的兴起使越来越多的普通个体能够利用闲置资源为消费者提供服务,成为共享服务者。然而,学术界对共享服务者的特性及其对消费者价值共创行为的影响尚缺乏深入探讨。本文通过理论分析将共享服务者特性归纳为社交性与自主性,并基于刻板印象理论构建了共享服务者特性对消费者价值共创行为的影响机理模型,分别使用大样本网络评论数据和消费者问卷调查数据对共享服务者特性和影响机理模型进行了检验。研究发现:社交性仅对消费者公民行为具有显著的正向影响作用,而自主性仅对消费者参与行为具有显著的正向影响作用。此外,社交性和自主性的交互效应能够通过激发消费者的欣赏情绪同时促进消费者的公民行为和参与行为。本文深化了对共享服务者特性如何从微观层面影响消费者价值共创行为的理解,并为共享服务者形象营销策略的制定提供了理论支持。

关键词：共享服务者特性消费者价值共创行为刻板印象理论自主性社交性

Bit error probability of distributed Turbo coded relay systems over quasi-static Rayleigh fading channels

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 41-45页

作者： peng Yue-xing WU Mu-zi ZHAO Hui wang Wen-bo Wireless Signal Processing and Network Laboratory Key Lab of Universal Wireless Communications Ministry of Education School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

As is known, distributed Turbo coding （DTC） performs close to the theoretic outage probability bound of a relay channel when correct decoding is assumed at the relay. However, decoding error is inevitable in practical fading channels due to the error-prone feature of radio channels, and the decoding error propagation in DTC scheme will severely degrade the error performance of the relay system. As a result, it is necessary to evaluate the error performance of the DTC scheme in multi-hop relaying wireless systems in practical fading channels. Moreover, the theoretical method of analysis provides an effective tool for obtaining the error performance besides lengthy simulations. In this article, the concept of equivalent signal-to-noise ratio （SNR） of the two-hop relay channel and the method of computing equivalent SNR are developed, and then the upper bound on the bit error probability （BEP） of DTC relay systems is analyzed by use of Turbo code＇s distance spectrum, the concept of uniform interleaver, the limit-before-averaging technique, and the union bound method. Both theoretical analysis and numerical simulation are implemented for relay systems with DTC scheme over quasi-static Rayleigh fading channels. The results show that the upper bound approaches the simulation results in the medium to high SNR region.

关键词： bit error probability distributed Turbo code relay network union bound distance spectrum SNR