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基于二通插装阀的液压系统标准控制单元设计与研究

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中国工程机械学报 2024年第3期22卷 331-336页

作者：王瑶李建德刘志奇弓成司邵珙李莎莎太原科技大学车辆与交通工程学院山西太原030024 太原科技大学机械工程学院山西太原030024 中国铁路太原局集团有限公司山西太原030013 四川航天烽火伺服控制技术有限公司四川成都611130

工程机械中普遍采用液压传动系统,要求系统集成化程度高,密封性好,能量损失小。鉴于此,基于二通插装阀的液压系统标准控制单元进行设计与研究。建立了三通集成块,并验证了其可行性。采用2个标准控制单元控制液压系统,列举了标准控制单元... 详细信息

工程机械中普遍采用液压传动系统,要求系统集成化程度高,密封性好,能量损失小。鉴于此,基于二通插装阀的液压系统标准控制单元进行设计与研究。建立了三通集成块,并验证了其可行性。采用2个标准控制单元控制液压系统,列举了标准控制单元的12种控制功能。同时,搭建了系统仿真模型,验证了标准控制单元控制液压系统的合理性。仿真结果表明:标准控制单元控制的回路可实现液压缸的快进和负负载流量再生功能,达到节能的目的。

关键词：液压系统标准控制单元二通插装阀负载口独立控制技术

Magnetic and luminescent properties of bifunctional composite Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+)

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Journal of Rare Earths 2024年第8期42卷 1568-1576,I0006页

作者： zhiqi Liang Zhili Zhang liu Li Wen Xu Decai Li School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing100044China Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Beijing100044China State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China

As a kind of non-destructive testing method,magnetic particle inspection is widely used in the fields of aviation and high-speed *** properties of magnetic fluorescent bifunctional composites,such as fluorescence intensity and magnetic properties,have increasing demands in magnetic particle *** earth compounds offer potential as novel materials for fluorescent magnetic bifunctional composites due to their excellent optical properties and extremely narrow emission *** this work,the rare earth fluorescent material Y_(2)O_(2)S:Eu^(3+) was synthesized by solid-state reaction ***_(3)O_(4)nanoparticles prepared by hydrothermal method were uniformly coated on the Y_(2)O_(2)S:Eu^(3+) particles through physical adsorption of *** obtained Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) exhibits dark red color under the ultraviolet *** additio n,X-ray diffractio n,morphology,photoluminescence and hyste resis loop of Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) were *** luminescence mechanism of Y_(2)O_(2)S:Eu^(3+) is described in detail Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) displays good paramagnetism and has a good controllability under a magnetic *** magnetic particle inspection of Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) was performed using a 4-pole electromagnet and a test piece *** magnetic fluorescent bifunctional composite presented in this work can be applied for non-destructive testing.

关键词： Bifunctional material Fe_(3)O_(4) Y_(2)O_(2)S:Eu^(3+) Luminescence Solid-state reaction Rare earths

Sample preparation for isotopic determination of boron in clay sediments

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Chinese Journal Of Geochemistry 2013年第2期32卷 203-211页

作者： ZHANG Yanling XIAO Yingkai MA Yunqi ZHUGE Qin liu zhiqi HE Maoyong LUO Chongguang MA Haizhou Key Laboratory of Salt Lake Resources and Chemistry Qinghai Institute of Salt Lakes Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences

The procedures of sample preparation for isotopic determination of boron in clay sediments is very cumbersome, by far, there haven't been relevant reports on that. In order to establish an effective method for sample preparation, a series of experiments were carried out. In this paper, boron in clay sediments was extracted with HCl solution and purified by two-step ion exchange method. Extracted HCl solution should be adjusted to alkalescency before passing through the Amberlite IRA 743 resin column due to the fact that Amberlite IRA 743 resin absorbs boron only from alkalescent solution. However, a mass of hydroxides of Al and Fe will be precipitated when the extracted HCl solution becomes alkalescent. Hydroxides of Al and Fe have a strong adsorption capacity for boron, which can cause boron isotope fractionation. To treat precipitated hydroxides of Al and Fe, four procedures, namely direct ion exchange (DRIE), decationizing ion exchange (DCIE), once sedimentation ion exchange (OSIE) and repeated sedimentation ion exchange (RSIE) were used and assessed. The influences of the four procedures on separation and extraction and isotopic composition of boron in experimental solutions and clay sediments were also discussed. According to the results, the DRIE, DCIE and OSIE are improper. The result of sample determination indicates that when extracting boron via RSIE, with the increase of precipitation times, there's an obvious decrease in boron content in the precipitated hydroxides while a sharp increase in recovery of boron and it is favorable for weakening the influence of boron isotope fractionation. But the process of RSIE is time consuming and it may introduce boron. It needs further research to establish a more effective sample preparation method for isotopic deter- mination of boron in clay sediments.

关键词：硼同位素组成同位素测定样品制备沉积物粘土离子交换法沉淀时间 HCl溶液

Heterostructured NiS_(2)@SnS_(2) hollow spheres as superior high-rate and durable anodes for sodium-ion batteries

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Science China Chemistry 2022年第7期65卷 1420-1432页

作者： Chongwei Li Jinchuan Hou Jingyi Zhang Xiaoyue Li Shiqi Jiang Guoqing Zhang Zhujun Yao Tiancun liu Shenghui Shen zhiqi liu Xinhui Xia Jie Xiong Yefeng Yang School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Provinceand School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China MOE Key Laboratory of Advanced Textile Materials and Manufacturing Technology Zhejiang Sci-Tech UniversityHangzhou 310018China Hangzhou Yanqu Information Technology Co. Ltd.Hangzhou 310003China

Tin-based sulfides have attracted increasing attention as anodes for sodium-ion batteries(SIBs) owing to their high theoretical capacity;however, the poor rate capability and inferior cycling stability caused by the low electrical conductivity, sluggish kinetics and drastic volume variations during cycling have greatly hampered their practical applications. Herein, heterostructured NiS_(2)@SnS_(2) hybrid spheres were delicately designed and constructed by anchoring interconnected SnS_(2) nanosheets on metalorganic frameworks(MOFs)-derived Ni S_(2) hollow spheres coupled with N-doped carbon skeleton through facile solvothermal and sulfurization/carbonization processes. The unique hollow heterostructure with highly conductive carbon matrix can effectively facilitate the charge transfer kinetics and ensure the desired buffer space while endowing more active sites and enhanced structural integrity, as demonstrated by the experimental and density functional theory(DFT) results. Benefitting from these merits, the NiS_(2)@SnS_(2) hybrid composite displays a high reversible capacity of 820 m Ah g^(-1) after 250 cycles at 1 A g^(-1), and retains a value of 673 m Ah g^(-1)after 1,300 cycles at 5 A g^(-1), manifesting the excellent high-rate and durable sodium storage behaviors when applied in SIBs. This study shall shed more light on the fabricating and interface engineering of other transition metal-based composite anodes for high-performance SIBs.

关键词： anode metal-organic frameworks heterostructure bimetallic sulfide sodium ion battery

Preparation and Characterization of a New Layered Double Hydroxide,Mg–Fe–Ce

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 354-355页

作者： liu zhiqi LI Lijuan CHEN Yunfa ZHANG Yanling Key Laboratory of Salt Lake Resources and Chemistry Qinghai Institute of Salt LakesChinese Academy of Sciences Institute of Process Engineering Chinese Academy of Sciences

1 Introduction In the present paper,MgCl2·6H2O,FeCl3·6H2O,and CeCl3·6H2O were used as raw materials in the precipitationhydrothermal method to synthesize MgF eC e *** effects of the Fe:Ce molar ratio on the composi... 详细信息

关键词： Ce Preparation and Characterization of a New Layered Double Hydroxide,Mg Cl Fe

表面织构-活性屏离子氮化复合处理对38CrMoAl钢摩擦学行为的影响

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太原理工大学学报 2024年第3期55卷 483-492页

作者：王杰陈伟敬林乃明王强王焕焕袁烁刘志奇曾群锋吴玉程太原理工大学材料科学与工程学院太原030024 太重集团榆次液压工业有限公司山西晋中030621 太原科技大学机械工程学院太原030024 西安交通大学现代设计及转子轴承系统教育部实验室西安710049 合肥工业大学有色金属与加工技术国家地方联合工程研究中心合肥230009

【目的】38CrMoAl钢是液压泵柱塞常用材质之一,其表面性能对液压泵长寿命安全服役尤为重要。磨损是液压泵柱塞的主要失效方式,采用表面强化处理能够突破其性能极限,是实现液压泵高性能、高可靠运行的有效途径。【方法】采用表面织构化... 详细信息

【目的】38CrMoAl钢是液压泵柱塞常用材质之一,其表面性能对液压泵长寿命安全服役尤为重要。磨损是液压泵柱塞的主要失效方式,采用表面强化处理能够突破其性能极限,是实现液压泵高性能、高可靠运行的有效途径。【方法】采用表面织构化和活性屏离子氮化的复合处理工艺对38CrMoAl钢进行表面形性调控,以期实现其表面强化方法。先利用激光加工技术在38CrMoAl钢表面制备凹坑织构,再对38CrMoAl钢和表面织构化38CrMoAl钢进行活性屏离子氮化处理。借助球-盘式摩擦磨损试验机研究表面织构-活性屏离子氮化复合处理对38CrMoAl钢摩擦学行为的影响。【结果】结果表明,38CrMoAl钢表面生成了ε-Fe2-3N、γ'-Fe4N和CrN;氮化层表面致密且无明显裂纹和孔洞;氮化层均匀、连续,由白亮层和扩散层组成。氮化层的截面硬度呈梯度分布,试样表面硬度最高,随着距表面距离的增大,硬度逐渐降低。38CrMoAl钢相关试样与Al_(2)O_(3)球的干滑动摩擦结果可知,38CrMoAl钢的摩擦系数为0.40,而表面织构-活性屏离子氮化38CrMoAl钢的摩擦系数为0.36;经复合处理后,38CrMoAl钢的磨损失重降低了92.5%.复合处理显著提高了38CrMoAl钢的摩擦学性能。

关键词：表面织构活性屏离子氮化复合处理 38CrMoAl钢摩擦学性能

维普期刊数据库博看期刊

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维立西呱治疗慢性心力衰竭的效果分析

中国社区医师 2024年第15期40卷 8-10页

作者：刘志启孙宗丽孟祥江陈明和潍坊市昌乐县人民医院心内二科山东潍坊262400

目的:分析维立西呱治疗慢性心力衰竭的效果。方法:选取2023年6月—2024年1月昌乐县人民医院收治的慢性心力衰竭患者110例作为研究对象,采用随机数字表法分为对照组与研究组,各55例。对照组实施常规抗心力衰竭治疗,研究组在对照组基础上... 详细信息

目的:分析维立西呱治疗慢性心力衰竭的效果。方法:选取2023年6月—2024年1月昌乐县人民医院收治的慢性心力衰竭患者110例作为研究对象,采用随机数字表法分为对照组与研究组,各55例。对照组实施常规抗心力衰竭治疗,研究组在对照组基础上给予维立西呱治疗。比较两组治疗效果。结果:研究组治疗总有效率高于对照组,差异有统计学意义(P=0.028)。治疗后,两组N末端B型利钠肽前体水平低于治疗前,且研究组低于对照组,差异有统计学意义(P0.05)。结论:维立西呱治疗慢性心力衰竭的效果显著,能够有效改善心功能,减轻临床症状,且安全性较好。

关键词：慢性心力衰竭维立西呱心功能

基于NLRP3炎症小体介导细胞焦亡探讨中医药防治自身免疫性甲状腺炎

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中医学报 2024年第2期39卷 297-303页

作者：陈言岳新冯志海牧亚峰刘昱君刘峙岐史晓雪河南中医药大学第一临床医学院河南郑州450000 河南中医药大学第一附属医院河南郑州450000

免疫失衡和炎症反应一直是自身免疫性甲状腺炎(autoimmune thyroiditis,AIT)研究的热点。先天免疫系统失调、下游炎症因子的分泌激活NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NL... 详细信息

免疫失衡和炎症反应一直是自身免疫性甲状腺炎(autoimmune thyroiditis,AIT)研究的热点。先天免疫系统失调、下游炎症因子的分泌激活NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)等经典炎症小体,诱导细胞焦亡过程,而坏死的甲状腺组织细胞又可释放ATP等相关损伤信号,促进免疫细胞聚集、浸润,加重自身免疫损伤,导致AIT的发病。故细胞焦亡为AIT发病机制的研究提供了新思路,抑制炎症小体介导的细胞焦亡过程或可成为治疗AIT的新靶点。细胞焦亡的过程是阴阳消长的过程,“虚”为细胞焦亡之本,“痰、瘀、毒”为细胞焦亡之标,可通过理气化痰、清热利湿、化痰除瘀、益气养阴等途径调整体内阴阳,使其恢复平衡状态。多种中药有效成分及中药复方可通过调控NLRP3炎性小体与细胞焦亡从而改善AIT症状,但这些研究仅仅基于免疫平衡机制探讨中药对AIT的治疗作用,中药单体及复方干预NLRP3炎症小体介导的甲状腺细胞焦亡过程研究较少。因此,基于细胞焦亡机制探讨中医药干预AIT的研究十分必要,可进一步明确中药治疗AIT的作用靶点,为中医药治疗AIT提供用药思路。

关键词：自身免疫性甲状腺炎细胞焦亡 NLRP3炎症小体中药

OsMKKK70 regulates grain size and leaf angle in rice through the OsMKK4-OsMAPK6-OsWRKY53 signaling pathway

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Journal of Integrative Plant Biology 2021年第12期63卷 2043-2057页

作者： zhiqi liu Enyang Mei Xiaojie Tian Mingliang He Jiaqi Tang Min Xu Jiali liu Lu Song Xiufeng Li Zhenyu Wang Qingjie Guan Qijiang Xu Qingyun Bu Key Laboratory of Saline-alkali Vegetation Ecology Restoration(Northeast Forestry University) Ministry of EducationHarbin 150040China College of Life Science Northeast Forestry UniversityHarbin 150040China Northeast Institute of Geography and Agroecology Key Laboratory of Soybean Molecular Design BreedingCASHarbin 150081China University of Chinese Academy of Sciences Beijing 100049China School of Laboratory Medicine Youjiang Medical University for NationalitiesBaise 533000China The Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100101China

Grain size and leaf angle are key agronomic traits that determine final yields in ***,the underlying molecular mechanisms are not well *** we demonstrate that the Oryza sativa Mitogen Activated Protein Kinase Kinase Kinase OsMKKK70 regulates grain size and leaf angle in *** OsMKKK70 caused plants to produce longer *** osmkkk62/70 double mutant and the osmkkk55/62/70 triple mutant displayed significantly smaller seeds and a more erect leaf angle compared to the wild type,indicating that OsMKKK70 functions redundantly with its homologs Os MKKK62 and Os *** analysis demonstrated that OsMKKK70 is an active kinase and that OsMKKK70 interacts with Os MKK4 and promotes Os MAPK6 *** addition,the osmkkk62/70 double mutant showed reduced sensitivity to Brassinosteroids(BRs).Finally,overexpressing constitutively active Os MKK4,Os MAPK6,and Os WRKY53 can partially complement the smaller seed size,erect leaf,and BR hyposensitivity of the osmkkk62/70 double *** together,these findings suggest that OsMKKK70 might regulate grain size and leaf angle in rice by activating Os MAPK6 and that OsMKKK70,Os MKK4,Os MAPK6,and Os WRKY53 function in a common signaling pathway that controls grain shape and leaf angle.

关键词： Brassinosteroids MAPK signaling OsMKKK70 rice seed size