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Synthesis, Crystal Structure and Luminescence of a Cadmium(Ⅱ) Coordination Polymer with 3,6-Connected rtl Topology

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Chinese Journal of Structural Chemistry 2016年第2期35卷 293-297页

作者： XUE Li-Ping SHAN Li-Li feng wen-jing College of Chemistry and Chemical Engineering Luoyang Normal University

A new cadmium（Ⅱ） coordination polymer,[Cd（Hcna）2]n（1）,was hydrothermally synthesized based on 5-（4-carboxyphenoxy）nicotinic acid（H2cna） organic linker.X-ray singlecrystal diffraction determination reveals that 1 crystallizes in the monoclinic P21/c space group,with a = 10.101（2）,b = 7.9139（17）,c= 15.627（3） A,β= 103.364（3）°,V= 1215.4（4） A^3,Z=2,Mr= 628.81,Dc = 1.718 Mg/m^3,μ= 0.963 mm^（-1）,F（000） = 628,the final R = 0.0177 and wR = 0.0432 for 2263 observed reflections with I 〉2σ（I）.In 1,the Cd（Ⅱ） cations are connected by nicotiniate units to form a two-dimensional（2D） layer,and it is further linked through benzoate units to form a three-dimensional（3D） ***,the structure of 1 represents a 3,6-connected 3D rtl ***,thermal stability and photoluminescent property of 1 have also been investigated.

关键词： cadmium coordination polymer crystal structure 5-(4-carboxyphenoxy)nicotinic acid rtl topology luminescence

Corporate Credit Ratings Based on Hierarchical Heterogeneous Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 257-271页

作者： Bo-jing feng Xi Cheng Hao-Nan Xu wen-Fang Xue Center for Research on Intelligent Perception and Computing National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China

order to help investors understand the credit status of target corporations and reduce investment risks,the corporate credit rating model has become an important evaluation tool in the financial *** models are based on statistical learning,machine learning and deep learning especially graph neural networks(GNNs).However,we found that only few models take the hierarchy,heterogeneity or unlabeled data into account in the actual corporate credit rating ***,we propose a novel framework named hierarchical heterogeneous graph neural networks(HHGNN),which can fully model the hierarchy of corporate features and the heterogeneity of relationships between *** addition,we design an adversarial learning block to make full use of the rich unlabeled samples in the financial *** experiments conducted on the public-listed corporate rating dataset prove that HHGNN achieves SOTA compared to the baseline methods.

关键词： Corporate credit rating hierarchical relation heterogeneous graph neural networks adversarial learning

Effect of TiO_(2) addition on microstructures and properties of Mgo-Cao refractory aggregates

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Journal of Iron and Steel Research International 2024年第6期31卷 1547-1554页

作者： Shuai Zhang jing-ran Wang Yuan-gao Li feng-you Li wen Yan Hui-ying Shi The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Joint International Research Laboratory of Refractories and Metallurgy Wuhan 430081HubeiChina Shanxi Luweibao Taigang Refractory Co. Ltd.Taiyuan 030003ShanxiChina

MgO-CaO(40 wt.%CaO)refractory aggregates were prepared using the calcined dolomite and light-burned magnesia fine powder as raw materials and TiO_(2) as *** effect of TiO_(2) on their phase composition,microstructures and properties was investigated by X-ray diffraction and scanning electron *** properties such as bulk density,apparent porosity,relative aggregate tube strength and hydration resistance were also *** results showed that the CaTiO_(3) generated by the reaction between CaO and TiO_(2) was distributed around the CaO grain boundaries and intermittently distributed with MgO,which formed an isolation layer around CaO and greatly improved the hydration ***,the introduction of TiO_(2) promoted sintering and increased the grain size,further improving the strengths and hydration resistance of the *** addition,the most significant enhancement in the hydration resistance and strengths of the samples was achieved when 1.0-2.0 wt.%TiO_(2) was *** this case,the relative strength of aggregate increased from 33.3% to 37.3%-43.1%,and the mass gain after the hydration test decreased from 3.13% to 1.26%-1.45%.

关键词： MgO-CaO refractory aggregate TiO_(2)addition Phase composition Microstructure Hydration resistance

营养健康食堂建设问题和模式分析:以中国两地试点为例

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中国食物与营养 2024年第2期30卷 14-17页

作者：冯靖雯刘爱玲宫伟彦袁帆仇玉洁张文彬丁彩翠中国疾病预防控制中心营养与健康所北京100050

目的:对照《营养健康食堂建设指南》要求,深入挖掘营养健康食堂试点建设中存在的问题,探索有效建设模式。方法:2021—2022年全程随访浙江省台州市4所学校、北京市海淀区8家单位和7所学校的营养健康食堂试点建设,采用问卷调查用餐人员130... 详细信息

目的:对照《营养健康食堂建设指南》要求,深入挖掘营养健康食堂试点建设中存在的问题,探索有效建设模式。方法:2021—2022年全程随访浙江省台州市4所学校、北京市海淀区8家单位和7所学校的营养健康食堂试点建设,采用问卷调查用餐人员1300人、食堂工作人员800人,收集食材及盐油糖人均消耗量变化,定期访谈相关人员。结果:食堂试点建设过程中存在的问题主要有营养标识未覆盖所有菜品、营养健康角利用率低、人员或资金保障不到位、缺乏专业人员、自制宣传材料存在科学问题、宣传活动形式单一、营养健康菜品烹饪及供应有待改善等。营养健康食堂有效建设模式应包括宣贯细化落实、政府统筹全局、专家全程参与、灵活运用科技、配备专业人员、完善食堂环境、开展针对性活动,以及关注过程和效果评估。结论:我国营养健康食堂建设初见成效,但在科学性、整体性、长期性等方面仍存在问题,营养与健康仍是今后食堂建设需要遵循的关键主题和方向。

关键词：营养健康食堂单位食堂学校食堂问题模式

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Antimicrobial resistance characteristics and phylogenetic relationships of pleuromutilin-resistant Enterococcus isolates from different environmental samples along a laying hen production chain

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Journal of Environmental Sciences 2024年第3期137卷 195-205页

作者： Cong Lin Yuxuan feng Xianjun Xie Haoyu Zhang Jie Wu Yixiao Zhu jing Yu jingyi feng wen Su Shanming Lai Anyun Zhang Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province Key Laboratory of Bio-Resource and Eco-Environment of Ministry of EducationCollege of Life SciencesSichuan UniversityChengdu 610065China

Antimicrobial resistance in the laying hen production industry has become a serious public health *** antimicrobial resistance and phylogenetic relationships of the common conditional pathogen Enterococcus along the laying hen production chain have not been systematically clarified.105 Enterococcus isolates were obtained from 115 environmental samples (air,dust,feces,fies,sewage,and soil) collected along the laying hen production chain (breeding chicken,chick,young chicken,and commercial laying hen).These Enterococcus isolates exhibited resistance to some clinically relevant antibiotics,such as tetracycline (92.4%),streptomycin (92.4%),and erythromycin (91.4%),and all strains had multidrug resistance *** genome sequencing characterized 29 acquired antibiotic resistance genes (ARGs) that conferred resistance to 11 classes of antibiotics in 51pleuromutilin-resistant Enterococcus isolates,and lsa(E),which mediates resistance to pleuromutilins,always co-occurred with lnu(B).Alignments with the Mobile Genetic Elements database identified four transposons (Tn554,Tn558,Tn6261,and Tn6674) with several ARGs(erm(A),ant(9)-la,fex(A),and optrA) that mediated resistance to many clinically important ***,we identified two new transposons that carried ARGs in the Tn554 family designated as Tn7508 and Tn7492.A complementary approach based on conventional multi-locus sequence typing and whole genome single nucleotide polymorphism analysis showed that phylogenetically related pleuromutilin-resistant Enterococcus isolates were widely distributed in various environments on different production *** results indicate that environmental contamination by antimicrobial-resistant Enterococcus requires greater attention,and they highlight the risk of pleuromutilin-resistant Enterococcus and ARGs disseminating along the laying hen production chain,thereby warranting effective disinfection.

关键词： Antimicrobial resistance Enterococcus Laying hen production chain Pleuromutilin

Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： jing-Lei Huang Guo-Bin Jia Li-feng Han wen-Qian Liu Li Huang Zheng-Han Yang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power *** model considers the impact of thermal properties of fluid variation on accuracy and has been validated with *** study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet ***,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also *** results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial *** simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

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精加工连杆外形用夹具设计

内燃机与配件 2024年第14期 73-75页

作者：章祥宝高峰张建宇吕俊杰冯文静穆增国杨利山西柴油机工业有限责任公司山西大同037036

某型号连杆大小头重量、总重量一致性及杆身表面强化要求非常严格,而连杆外形是影响连杆重量及提升表面喷丸强化指标的主要因素,通过设计制造一种适合的夹具,定位装夹稳定、可靠,保证连杆外形加工精度及精度的一致性,同时工件装卸方便,... 详细信息

某型号连杆大小头重量、总重量一致性及杆身表面强化要求非常严格,而连杆外形是影响连杆重量及提升表面喷丸强化指标的主要因素,通过设计制造一种适合的夹具,定位装夹稳定、可靠,保证连杆外形加工精度及精度的一致性,同时工件装卸方便,避免定位元件的非正常磨损,为保证连杆大小头重量、总重量一致性及杆身表面喷丸强化指标奠定基础。

关键词：定位间隙定位误差膨胀销磨损

Visible-Light-Driven Four-Component Radical Relay Aminocarbonylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第9期42卷 990-996页

作者： Bin Lu feng-Shuo Bao Zi-Wei He wen-jing Xiao Jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction College of ChemistryCentralChina Normal University152 Luoyu RoadWuhanHubei 430079China Wuhan Institute of Photochemistry and Technology 7North Bingang RoadWuhanHubei 430083China Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal UniversityGanzhouJiangxi 341000China

Catalytic four-component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl *** the significance of fluorine-containing groups,this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal ***,we report a visible-light-driven radical relay 1,2-perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CzIPN as organic photocatalyst.A wide range of alkenes and amines were well tolerated,providing the valuableβ-perfluoroalkylated amides with generally good yields and high chemoselectivity.

关键词： Visible light Photoredox catalysis Radical aminocarbonylation Multicomponent reaction Carbon monoxide Unactivated alkenes AmidesIReactionmechanisms

TESTS AND APPLICATIONS OF A BOUSSINESQ MODEL WITH AMBIENT CURRENT

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Journal of Hydrodynamics 2010年第4期22卷 526-536页

作者： ZHANG Hong-sheng WANG Wei-yuan feng wen-jing WANG Ya-ling YANG Jian-min State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Water Planning and Design Research Institute Shanghai 200232 China College of Transport and Communications Shanghai Maritime University Shanghai 200135 China

A new type Boussinesq model is proposed and applied for wave propagation in a wave flume of uniform depth and over a submerged bar with current present or absent,***,for the propagation of monochromatic incident wave with current absent,the Boussinesq model is tested in its complete form,and in a form without the introduction of utility velocity *** is validated that the introduction of utility velocity variables can improve the characteristics of velocity field,dispersion and *** versions of the Boussinesq models are of higher accuracy than the fully-nonlinear fourth-order model,which is one of the best forms among the existing traditional Boussinesq models that do not incorporate breaking mechanism in one ***,the Boussinesq model in its complete form is applied to simulating the propagation of bichromatic incident waves with current present or absent,respectively,and the modeled results are compared to the analytical ones or the experimental *** modeled results are reasonable in the case of inputting bichromatic incident waves with the strong opposing current present.

关键词： Boussinesq model ambient current wave-wave interactions velocity field bichromatic incident waves