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A Novel 3D Extended Network Cobalt Paradodecatungstate:Synthesis,Characterization and Crystal Structure of [Co(H_2O)_5]_2[Co(H_2O)_4]_3[H_2W_(12)O_(42)]·11H_2O

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1167-1174页

作者： WANG Jing-Ping REN Qing zhao jun-wei NIU Jing-Yang Institute of Molecular and Crystal Engineering College of Chemistry and Chemical Engineering Henan University Kaifeng Henan 475001 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhcu Fujian 350002 China

A cobalt paradodecatungstate [Co（H2O）5]2[Co（H2O）4]3[H2W12O42]·11H2O has been successfully synthesized and structurally characterized by X-ray crystallography. Structure analysis indicates that the title compound is of monoclinic, space group P21/n, with a = 13.449（3）, b = 19.585（4）, c = 13.990（3） °A, = 113.79（3）°, V = 3371.8（12） °A^3, Z = 2, R = 0.0519 and wR = 0.1242. The title compound exhibits a novel 3D extended network structure constructed by interconnecting the paradodecatungstate polyanion [H2W12O42]^10- clusters and cobalt^11 coordination ions.

关键词： paradodecatungstate polyoxometalate cobalt Keggin structure

施磷对紫花苜蓿土壤呼吸速率及活性有机碳组分的影响

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草业学报 2024年第2期33卷 80-92页

作者：魏孔钦赵俊威张前兵石河子大学动物科技学院新疆石河子832003

探究施磷对紫花苜蓿土壤呼吸速率及活性有机碳组分含量的影响,明确不同施磷处理条件下苜蓿田土壤呼吸速率及土壤活性有机碳组分之间的关系,以期为人工草地土壤固碳和可持续发展提供数据支撑。本试验采用随机区组设计,设置0(P_(0))、50(P... 详细信息

探究施磷对紫花苜蓿土壤呼吸速率及活性有机碳组分含量的影响,明确不同施磷处理条件下苜蓿田土壤呼吸速率及土壤活性有机碳组分之间的关系,以期为人工草地土壤固碳和可持续发展提供数据支撑。本试验采用随机区组设计,设置0(P_(0))、50(P_(1))、100(P_(2))和150 kg·hm^(-2)(P_(3))4种施磷水平,重复3次。研究不同施磷水平下紫花苜蓿0~60 cm土层的土壤有机碳(SOC)、微生物量碳(MBC)、溶解性有机碳(DOC)、颗粒有机碳(POC)、易氧化有机碳(EOC)含量、土壤温湿度及呼吸速率(R_S)。结果表明,不同土层SOC、MBC、DOC、POC和EOC含量随施磷量增加而升高,在P_(3)处理下达到最大,分别为15.77 g·kg^(-1)、0.42 g·kg^(-1)、0.34 g·kg^(-1)、4.68 g·kg^(-1)和2.06 g·kg^(-1),且显著大于P_(0)处理(P<0.05)。SOC、MBC、DOC、POC及EOC在垂直分布上均以0~20 cm土层含量最高,分别占总含量的38.35%~41.58%、38.31%~39.49%、45.54%~46.65%、46.29%~47.35%和40.40%~44.17%。施磷处理使土壤R_(S)提高了0.31%~14.90%,且刈割前后差异显著(P<0.05)。随施磷量增加,不同土层MBC、DOC、POC及EOC的敏感指数均呈上升趋势。施磷处理下0~30 cm土层微生物量碳敏感指数最高,30~60 cm土层易氧化有机碳敏感指数最高。建议用微生物量碳指示表层土壤有机碳的变化,而易氧化有机碳可指示深层土壤有机碳的变化。各活性有机碳组分有效率随施磷量增加变化规律不明显。结构方程结果表明,施磷可直接影响SOC含量,也可通过改变MBC、DOC、POC和EOC含量而间接影响SOC含量。综上,施磷提高了土壤R_S,但持续磷输入整体增加了苜蓿田土层内SOC、MBC、DOC、POC和EOC含量,提高了固碳潜力及土壤质量,可为全球磷沉降背景下人工草地生态系统土壤有机碳动态变化及人工草地管理提供科学依据。

关键词：磷苜蓿土壤呼吸土壤有机碳活性有机碳

维普期刊数据库博看期刊

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基于母线功率前馈的配网PET电压均衡控制

电力电子技术 2024年第4期58卷 22-26页

作者：张锐赵俊炜刘铮徐睿烽广东电网有限责任公司广东东莞523000 华南理工大学广东广州510641

针对配网级联型电力电子变压器(PET)提出了一种基于低压直流母线功率前馈的电压和功率均衡控制策略。该控制策略将PET低压直流母线的能量需求前馈至输入级,指导输入级实现各级模块的功率均衡控制,同时利用隔离级来稳定各模块的直流电压... 详细信息

针对配网级联型电力电子变压器(PET)提出了一种基于低压直流母线功率前馈的电压和功率均衡控制策略。该控制策略将PET低压直流母线的能量需求前馈至输入级,指导输入级实现各级模块的功率均衡控制,同时利用隔离级来稳定各模块的直流电压,并采用相同的稳压指令实现各级直流电压的均衡控制。所提控制策略不仅能够有效解决因各级模块参数不匹配所导致的电压与功率不均衡问题,同时减少了目前PET控制环节,降低了各模块间的电量耦合关系。仿真和实验验证了所提控制策略的有效性。

关键词：电力电子变压器功率前馈电压和功率均衡控制

Effects of the Specific Area and the Thermal Stability of a Polymer on the Catalytic Activities of Polymer Immobilized Co-Pd Catalysts by SAMI

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Chemical Research in Chinese Universities 2001年第4期17卷 439-444页

作者： WU Shi-hua wei wei ZHU Chang-ying HUANG wei-ping ZHANG Shou-min ZHENG Xiu-cheng ZHANG Shu-hong zhao wei-jun Department of Chemistry Naikai UniversityTianjin 300071P.R.China

Co-Pd bimetallic catalysts immobilized with four kinds of resins with different specific areas were prepared by means of the solvated metal atom impregnation (SMAI) method. The results of the XRD and the magnetic measurement showed that as the specific area of the resin increased, the particle sizes of Co and Pd on the catalysts with the same metal content decreased, so the catalytic activity of the catalysts for the hydrogenation of diacetone alcohol as well as the reduction of oxygen on the fuel cell electrode increased. Below 140 , the conversion of diacetone alcohol increased as the reaction temperature increased, and above 140 , the conversion decreased because of the rupture of the resin.

关键词： Cobalt-palladium catalyst Diacetone alcohol hydrogenation Fuel cell electrode

3-PRS serial-parallel machine tool error calibration and parameter identification

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重庆邮电大学学报（自然科学版） 2009年第2期21卷 284-291页

作者： zhao jun-wei DAI jun HUANG jun-jie School of Mechanical and Power Engineering Henan Polytechnic University Jiaozuo 454003P. R. China

3-PRS serial-parallel machine tool consists of a 3-degree-of-freedom (DOF) implementation platform and a 2-DOF X-Y platform. The error modeling and parameter identification methods were deduced based on 3-PRS serial-parallel machine tool. 3-PRS serial-parallel machine tool was researched, and the mechanism of error analysis, modeling, identification of error parameters and measurement equipment for the use of agency error of measurement were conducted. In order to achieve the geometric parameters calibration and error compensation of the serial-parallel machine tool, the nominal structural parameters of the controller was adjusted by identifying the structure of the machine tool. With the establishment of a vector space size chain, we can do the error analysis, error modeling, error measurement and error compensation can be done.

关键词：串并联机床参数辨识误差标定串行 3自由度误差建模代理平台结构参数

Hydrogen Sulfide Promotes Root Organogenesis in Ipomoea batatas, Salix matsudana and Glycine max

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Journal of Integrative Plant Biology 2009年第12期51卷 1086-1094页

作者： Hua Zhang jun Tang Xiao-Ping Liu Yun Wang wei Yu wei-Yan Peng Fang Fang Dai-Fu Ma zhao-jun wei Lan-Ying Hu School of Biotechnology and Food Engineering Hefei University of Technology Hefei 230009 China Xuzhou Sweet Potato Research Center Chinese Academy of Agricultural Sciences National Sweet Potato Improvement Center Xuzhou 221 121 China Anhui Academy of Agricultural Sciences Hefei 230031 China

In this report, we demonstrate that sodium hydrosulfide （NariS）, a hydrogen sulfide （H2S） donor, promoted adventitious root formation mediated by auxin and nitric oxide （NO）. Application of the HzS donor to seedling cuttings of sweet potato （Ipomoea batatas L.） promoted the number and length of adventitious roots in a dose-dependent manner. It was also verified that H2S or HS- rather than other sulfur-containing components derived from NariS could be attributed to the stimulation of adventitious root formation. A rapid increase in endogenous H2S, indole acetic acid （IAA） and NO were sequentially observed in shoot tips of sweet potato seedlings treated with HallS. Further investigation showed that H2S-mediated root formation was alleviated by N-1-naphthylphthalamic acid （NPA）, an IAA transport inhibitor, and 2-（4-carboxyphenyl）. 4,4,5,5-tetramethylimidazoline-1-oxyl-3-0xide （cPTIO）, an NO scavenger. Similar phenomena in H2S donor-dependent root organogenesis were observed in both excised willow （Salix matsudana var. tortuosa Vilm） shoots and soybean （Glycine max L.） seedlings. These results indicated that the process of H2S-induced adventitious root formation was likely mediated by IAA and NO, and that H2S acts upstream of IAA and NO signal transduction pathways.

关键词： auxin hydrogen sulfide nitric oxide root organogenesis sweet potato.

Progress and prospects of chiral nanomaterials for biosensing platforms

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Rare Metals 2024年第6期43卷 2469-2497页

作者： Yu-Cheng Ouyang Bong-jun Yeom Yuan zhao wei Ma School of Food Science and Technology State Key Laboratory of Food Science and ResourcesJiangnan UniversityWuxi 214122China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnanUniversityWuxi214122China Department of Chemical Engineering Hanyang UniversitySeoul04763RepublicofKorea

Chiral nanomaterials have distinct chiroptical properties of preferential interactions to circularly polarized ***-based biosensors have emerged for detection of biomolecules,ions and cells in recent *** review provides an extensive overview of biosensors based on chiral nanomaterials,starting with approaches to chiral nanomaterials construction in terms of fabrication *** of chiral nanomaterials and their biosensor applications is presented for different material types,with special emphasis on the role and importance of material properties and signal generation in *** assessed the technological prospects of the emerging fields of chiral construction,circularly polarized luminescence,Raman optical activity and so on along with their current *** venues for future research on chiral nanomaterials in fabrication,biosensing,disease diagnosis and treatment are also presented in the review.

关键词： Chiral nanomaterials Circular dichroism Biosensors

Aerodynamic/stealth design of S-duct inlet based on discrete adjoint method

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 725-746页

作者： jun DENG Ke zhao Lin ZHOU wei ZHANG Bowen SHU Jiangtao HUANG Zhenghong GAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aerospace Technology Institute of China Aerodynamic Research and Development CenterMianyang 621000Sichuan ProvinceChina

It is a major challenge for the airframe-inlet design of modern combat aircrafts,as the flow and electromagnetic wave propagation in the inlet of stealth aircraft are very *** this study,an aerodynamic/stealth optimization design method for an S-duct inlet is *** upwind scheme is introduced to the aerodynamic adjoint equation to resolve the shock wave and flow *** multilevel fast multipole algorithm(MLFMA)is utilized for the stealth adjoint equation.A dorsal S-duct inlet of flying wing layout is optimized to improve the aerodynamic and stealth *** the aerodynamic and stealth characteristics of the inlet are effectively ***,the optimization results are analyzed,and it shows that the main contradiction between aerodynamic characteristics and stealth characteristics is the centerline and crosssectional *** S-duct is smoothed,and the cross-sectional area is increased to improve the aerodynamic characteristics,while it is completely opposite for the stealth *** radar cross section(RCS)is reduced by phase cancelation for low frequency *** method is suitable for the aerodynamic/stealth design of the aircraft airframe-inlet system.

关键词： S-duct inlet aerodynamic/stealth optimization design discrete adjoint upwind scheme multilevel fast multipole algorithm(MLFMA)

Risk identification and safety assessment of human-computer interaction in integrated avionics based on STAMP

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Journal of Systems Engineering and Electronics 2024年第3期35卷 689-706页

作者： zhao Changxiao LI Hao ZHANG wei DAI jun DONG Lei School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China Shenzhen Dajiang Innovation Technology Co. Ltd.Shenzhen 518057China Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation Administration of ChinaTianjin 300300China

To solve the problem of risk identification and quantitative assessment for human-computer interaction(HCI)in complex avionics systems,an HCI safety analysis framework based on system-theoretical process analysis(STPA)and cognitive reliability and error analysis method(CREAM)is *** can identify unsafe control actions and find the causal path during the interaction of avionics systems and pilot with the help of formal verification tools *** common performance conditions(CPC)of avionics systems in the aviation environment is established and a quantitative analysis of human failure is carried *** the head-up display(HUD)system interaction process as an example,a case analysis is carried out,the layered safety control structure and formal model of the HUD interaction process are *** the interactive behavior“Pilots approaching with HUD”,four unsafe control actions and35 causal scenarios are identified and the impact of common performance conditions at different levels on the pilot decision model are *** results show that HUD's HCI level gradually improves as the scores of CPC increase,and the quality of crew member cooperation and time sufficiency of the task is the key to its *** case analysis,it is shown that STPACREAM can quantitatively assess the hazards in HCI and identify the key factors that impact safety.

关键词： avionics human-computer interaction(HCI) safety assessment system-theoretic accident model and process human reliability analysis