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基础货币投放渠道变迁对货币政策有效性的影响

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管理评论 2024年第1期36卷 71-86页

作者：王少林林建浩徐淑一广东财经大学金融学院广州510320 中山大学岭南学院广州510275

货币政策有效性下降是我国宏观政策近年来的典型事实,而探索其原因及优化措施成为理论界与实务界的重要议题。为此,本文基于基础货币投放渠道变迁视角,在理论分析的基础上,通过宏观经济效应分析与微观机制检验,多层次论证基础货币投放... 详细信息

货币政策有效性下降是我国宏观政策近年来的典型事实,而探索其原因及优化措施成为理论界与实务界的重要议题。为此,本文基于基础货币投放渠道变迁视角,在理论分析的基础上,通过宏观经济效应分析与微观机制检验,多层次论证基础货币投放渠道变迁如何影响我国货币政策有效性。研究得出:第一,根据具有时变参数的VAR模型估计结果,不同基础货币投放渠道的宏观经济效应存在较大差异,但并未发现明显的时变特征,因此我国货币政策有效性下降的重要原因之一是基础货币投放渠道的结构性改变;第二,在微观机制方面,不同基础货币投放渠道对企业投资的提升作用存在较大差异,这是基础货币投放影响货币政策有效性的重要渠道;第三,不同基础货币投放渠道缓解企业融资约束的能力具有显著区别。籍此,本文为优化我国货币政策有效性提出了富有建设性的建议。

关键词：基础货币投放渠道货币政策有效性企业投资融资约束

基于B/S架构的空调智能监控系统设计与实现

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软件导刊 2024年第3期23卷 114-120页

作者：余秋亮王少林王泽宇山东建筑大学信息与电气工程学院山东济南250100 山东邦展建筑设计有限公司山东济南250101

为解决空调系统设备种类众多、协议不统一的问题,针对空调系统的监控需求,设计了基于分布式监控与集中管理模式、B/S架构的空调智能监控系统。首先,在设备监控层利用多线程技术实现设备实时数据的采集处理,采用多协议转换技术进行统一... 详细信息

为解决空调系统设备种类众多、协议不统一的问题,针对空调系统的监控需求,设计了基于分布式监控与集中管理模式、B/S架构的空调智能监控系统。首先,在设备监控层利用多线程技术实现设备实时数据的采集处理,采用多协议转换技术进行统一协议转换、封装,将多种协议数据上传存储到数据库服务器。然后,通过模糊自适应PID控制器对监测数据进行轮询计算,调节变频器实时控制空调系统温度。最后,通过Web服务端口访问数据库服务器,实现系统集成与数据交换,建立集中控制、管理、运维的集成平台,实现系统设备的统一监控和调度,系统的统一部署和高可用性,完成空调监控系统的界面可视化并提升空调系统智能化水平。实践表明,该系统运行稳定,能实时监控空调运行状况,且具有较高的扩展性与管理效率。

关键词：空调监控系统 B/S架构分布式多协议转换模糊自适应PID

Lean blowout characteristics of spray flame in a multi-swirl staged combustor under different fuel decreasing rates

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Chinese Journal of Aeronautics 2022年第12期35卷 130-143页

作者： Qianpeng ZHAO Jinhu YANG Cunxi LIU Fuqiang LIU shaolin wang Yong MU Gang XU Junqiang ZHU Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Light-duty Gas Turbine Beijing 100190China

Lean Blow Out(LBO)poses a significant safety hazard when occurring in *** the lower stability limits of gas turbine combustors and the characteristics of spray flame close to LBO are imperative for safe *** objective of this work is to evaluate the effects of fuel decreasing rates and pressure drops of the injector on LBO performances in a multiswirl staged combustor equipped with an airblast injector.A set of hardware and control system was developed to realize a user-defined fuel supply ***-speed imaging was applied to record complete LBO processes under the conditions of linear fuel reduction and stable *** Image Velocimetry(PIV)and Planar Mie(PMie)scattering were used to acquire the flow fields and spray fields under non-reacting *** results have shown that LBO limits extend to leaner conditions as the pressure drop of the injector *** an increase of the fuel decreasing rate,the exhaust temperature before flame extinction increases,and the LBO Fuel-to-Air-Ratio(FAR)*** time evolution of the integral CH*intensity conforms to a linear function during the LBO *** Orthogonal Decomposition(POD)was used to analyze the dynamic characteristics of lean-burn *** different fuel decreasing rates and pressure drops of the injector,flames close to LBO present similar modal spatial distributions,alternately appearing axial,radial,high-order axial,and high-order radial oscillations.

关键词： Blowout Combustors Flame dynamics High-speed imaging POD

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高温高速来流条件下扇形喷嘴雾化特性研究

推进技术 2024年第6期45卷 154-163页

作者：施刚强吴杰胡喆刘舆帅王少林王凯兴穆勇阮昌龙郭玉超王月徐纲何志霞刘富强江苏大学流体机械工程技术研究中心江苏镇江212013 中国科学院工程热物理研究所轻型动力重点实验室北京100190 中国科学院大学航空宇航学院北京100190 青岛航空技术研究院山东青岛266000 江苏大学能源研究院江苏镇江212013

为了探索扇形喷嘴在加力燃烧室应用的可行性,采用Mie散射和PLIF激光测量系统对其在高温高速环境中的雾化特性开展了研究。获得了在不同来流温度、来流马赫数以及燃油流量条件下燃油轨迹变化规律、蒸发距离及气液两相分布特性,并拟合了... 详细信息

为了探索扇形喷嘴在加力燃烧室应用的可行性,采用Mie散射和PLIF激光测量系统对其在高温高速环境中的雾化特性开展了研究。获得了在不同来流温度、来流马赫数以及燃油流量条件下燃油轨迹变化规律、蒸发距离及气液两相分布特性,并拟合了穿透深度经验公式。试验结果表明:在来流温度850~1 250 K,马赫数为0.15~0.35,燃油流量6~14 g/s的工况下,(1)温度升高,燃油穿透深度减小,蒸发距离变短;(2)马赫数增加,燃油穿透深度减小,蒸发距离变长;(3)燃油流量增加,燃油穿透深度增加,对蒸发距离影响较小;(4)气相燃油分布区约为液相的6倍。

关键词：加力燃烧室扇形喷嘴横向射流航空煤油雾化特性

Characterization of a Novel Gene, srpA, Conferring Resistance to Streptogramin A, Pleuromutilins, and Lincosamides in Streptococcus suis

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Engineering 2022年第2期8卷 85-94页

作者： Chaoyang Zhang Lu Liu Peng Zhang Jingpo Cui Xiaoxia Qin Lichao Ma Kun Han Zhanhui wang shaolin wang Shuangyang Ding Zhangqi Shen College of Veterinary Medicine China Agricultural UniversityBeijing 100193China Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety China Agricultural UniversityBeijing 100193China

Antimicrobial resistance is undoubtedly one of the greatest global health threats. The emergence of multidrug-resistant(MDR) Gram-positive pathogens, such as methicillin-resistant Staphylococcus aureus(MRSA), vancomycin-resistant Enterococcus faecium(VRE), and β-lactamase-resistant Streptococcus pneumonia, has severely limited our antibiotic arsenal. Numerous ribosome-targeting antibiotics, especially pleuromutilins, oxazolidinones, and streptogramins, are viewed as promising alternatives against aggressive MDR pathogens. In this study, we identified a new adenosine triphosphate(ATP)-binding cassete(ABC)-F family determinant, srp A, in Streptococcus suis(S. suis) by means of a comparative analysis of the whole-genome sequences of tiamulin(TIA)-resistant and TIA-sensitive bacteria. Functional cloning confirmed that the deduced gene can mediate cross-resistance to pleuromutilins, lincosamides, and streptogramin A in S. suis and S. aureus. A sequence alignment revealed that Srp A shares the highest amino acid identity with Vga(E)(36%) and shows canonical characteristics of ABC-F family *** Srp A-ribosome docked compounds, the extended loop region of Srp A approaches the valnemulinbinding pocket in the ribosome peptidyl-transferase center and competes with bound valnemulin. A detailed mutational analysis of the loop residues confirmed that this domain is crucial for Srp A activity,as substitutions or truncations of this region affect the efficiency and specificity of antibiotic *** antibiotics accumulation indicated that Srp A does not act as an efflux pump, while a ribosome binding assay supported the protective effects of Srp A on the ribosome by preventing antibiotic binding as well as displacing bound drugs. These findings clarify the mechanisms underlying resistance to ribosomal antibiotics.

关键词： SrpA Streptococcus suis Antibiotic resistance Ribosome ABC-F family proteins

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管片接缝对地铁振动源强影响现场测试研究

现代城市轨道交通 2024年第9期 113-118页

作者：陈江雪姜博龙谭新宇王少林何宾中国铁路设计集团有限公司天津300308

地铁振动源强的选取是开展环境振动评估的核心环节。目前,地铁盾构隧道普遍采用管片拼接方式,在进行振动源强测试时存在跨越管片接缝和不跨管片接缝2种情况,文章通过现场行车测试和锤击试验,研究管片接缝对振动源强的影响效果和振动传... 详细信息

地铁振动源强的选取是开展环境振动评估的核心环节。目前,地铁盾构隧道普遍采用管片拼接方式,在进行振动源强测试时存在跨越管片接缝和不跨管片接缝2种情况,文章通过现场行车测试和锤击试验,研究管片接缝对振动源强的影响效果和振动传递特征。结果表明:对于最大Z振级评价,全天车次最大Z振级差值统计结果的平均值为0.77 dB,最大值为2.22 dB;对于典型工况分频最大振级评价,Z计权前分频最大振级在200 Hz频率处,测点1和测点2的差值为3.44 dB,Z计权后分频最大振级在50 Hz频率处,测点1和测点2的差值为0.45 dB;管片接缝在141~346 Hz和410~502 Hz频率段具有振动减小作用。相关研究可为地铁振动源强测点选择提供参考。

关键词：地铁管片接缝振动源强锤击试验传递函数

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An eikonal equation-based earthquake location method by inversion of multiple phase arrivals

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Science China Earth Sciences 2024年第6期67卷 1802-1817页

作者： Gaoyue LAO Dinghui YANG shaolin LIU Guiju DONG Wenshuai wang Kui LIU National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China School of Earth Sciences Yunnan UniversityKunming 650091China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China

The precise determination of earthquake location is the fundamental basis in seismological community,and is crucial for analyzing seismic activity and performing seismic *** arrivals are generally used to practically determine earthquake ***,first-arrival traveltimes are not sensitive to focal ***,they cannot accurately constrain focal *** improve the accuracy,researchers have analyzed the depth phases of earthquake *** traveltimes of depth phases are sensitive to focal depths,and the joint inversion of depth phases and direct phases can be implemented to potentially obtain accurate earthquake ***,researchers can determine earthquake locations in layered *** layered models can only represent the first-order feature of subsurface structures,the advantages of joint inversion are not fully explored if layered models are *** resolve the issue of current joint inversions,we use the traveltimes of three seismic phases to determine earthquake locations in heterogeneous *** three seismic phases used in this study are the first P-,sPg-and *** calculate the traveltimes of the three seismic phases by solving an eikonal equation with an upwind difference scheme and use the traveltimes to determine earthquake *** verify the accuracy of the earthquake location method by the inversion of three seismic phases,we take the 2021 M_(S)6.4 Yangbi,Yunnan earthquake as an example and locate this earthquake using synthetic and real seismic *** tests demonstrate that the eikonal equation-based earthquake location method,which involves the inversion of multiple phase arrivals,can effectively improve earthquake location accuracy.

关键词： Earthquake location Eikonal equation Fast marching method Heterogeneous model

Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 129-139页

作者： Li, Hui wang, Gang Hu, Jin Li, Jun Huang, Jiaxu Xu, shaolin Southern Univ Sci & Technol Dept Mech & Energy Engn Shenzhen 518000 Peoples R China

The practical application of lithium (Li) metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites. To address this challenge, this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper (Cu) current collectors. Specifically, this approach enhances the prevalence of Cu (100) facets within the grooves, effectively lowering the overpotential for Li nucleation and promoting preferential Li deposition. Unlike approaches that modify the entire surface of collectors, our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance metrics. The half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42% over 350 cycles at 1 mA cm(-2). The symmetric cell can cycle stably for 1600 h at 0.5 mA cm(-2). Furthermore, when integrated with LiFePO4 cathodes, the full-cell configuration demonstrates outstanding capacity retention of 92.39% after 400 cycles at a 1C discharge rate. This study introduces a novel technique for fabricating selective lithiophilic three-dimensional (3D) Cu current collectors, thereby enhancing the performance of Li metal batteries. The insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures.

关键词： copper current collector heat treatment laser processing lithium metal battery selective crystalline orientation ABNORMAL GRAIN-GROWTH LI METAL DEPOSITION TEXTURE ENERGY

Prevalence of Salmonella and Antimicrobial Resistance in Isolates from Food Animals—Six PLADs,China,2019

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China CDC weekly 2021年第24期3卷 514-517页

作者： Tingting Cao Peng Liu Yiming Li Mingquan Cui Chunping Zhang Yang wang Zhangqi Shen Jianzhong Shen Yuebin Ke shaolin wang Yongning Wu College of Veterinary Medicine China Agricultural UniversityBeijingChina China Institute of Veterinary Drug Control BeijingChina Key Laboratory of Molecular Epidemiology of Shenzhen Shenzhen Center for Disease Control and PreventionShenzhenGuangdongChina National Health Commission Key Laboratory of Food Safety Risk Assessment Food Safety Research Unit(2019RU014)of Chinese Academy of Medical ScienceChina National Center for Food Safety Risk AssessmentBeijingChina.

Summary What is already known about this topic?Salmonella causes acute and chronic diseases in food animals,and infected food animals are one of the most important source of human *** does this report contribute?The prevalence of Salmonella was 10.5%in chicken samples,24.4%in pig,23.3%in duck,and 29.4%in *** isolates were highly resistant to ampicillin(59.60%).What are the implications for public health practices?Data on Salmonella infections among food animals in China could help identify sources and factors related to the spread of Salmonella in food animals and food production chains.

关键词： chains food spread