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An introduction to the novel vacuum plume effects experimental system

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Science China(Technological Sciences) 2016年第6期59卷 953-960页

作者： cai Guo Biao LING gui Long HE Bi Jiao School of Astronautics Beihang University

This paper introduces a newly developed vacuum Plume effects Experimental System(PES) used for plume effect tests of rocket engines and vacuum heat tests of satellites. The design level, manufacturing technique, and testing capabilities of the PES have reached a highly advanced level at home and abroad. The PES mainly consists of a vacuum chamber, vacuum acquisition system, nitrogen system, helium system, and parameter measurement system. A breakthrough was obtained on the Large Scale Cryo-Pumping System, which was based on a combined liquid nitrogen and liquid helium heat sink. An internal cryopump with a limiting temperature of 4.2 K and an efficient absorption area of 305 m2 was developed. The absorption capability of the cryopump was above 7×107 L/s. Vacuum plume tests were performed in the temperature ranges of ambient temperature, liquid nitrogen, and liquid helium. The experimental results showed that the plume test capability of PES is higher than that of similar foreign equipment STG and CHAFF-4. For 2 g/s and 117 N rocket engines, the dynamic vacuum degree of environment was 8.0×10?4 Pa(approximately 137 km height) and 1.1×10?2 Pa(approximately 106 km height), respectively.

关键词： vacuum plume effect liquid nitrogen heat sink liquid helium heat sink plume absorption pump

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多元投资主体共建职业教育集团建设路径探析

佳木斯大学社会科学学报 2024年第5期42卷 45-48页

作者：蔡雪敏严桂泉湄洲湾职业技术学院质量发展处福建莆田351119 福建幼儿师范高等专科学校宣传部福建福州350007

在全面推进职业教育提质培优、增值赋能的背景下,国家大力支持并推进职教集团化办学,鼓励实体化运作。文章系统分析了现有国内职教集团的运行模式、运行状态及各投资主体利益相关性,提出构建多元投资主体职教集团的建设对策,以期积极引... 详细信息

在全面推进职业教育提质培优、增值赋能的背景下,国家大力支持并推进职教集团化办学,鼓励实体化运作。文章系统分析了现有国内职教集团的运行模式、运行状态及各投资主体利益相关性,提出构建多元投资主体职教集团的建设对策,以期积极引导多元投资主体共建职教集团可持续发展,切实推进职教集团办学实体化运作。

关键词：多元主体职教集团建设路径

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An intelligent system for calculating the scale of rational,enlarged production of an underground non-ferrous metal mine

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Journal of China University of Mining and Technology 2008年第2期18卷 214-219页

作者： ZHENG Ming-gui cai Si-jing Civil ＆ Environment Engineering School University of Science and Technology Beijing Beijing 100083 China

The enlarged production scale of underground non-ferrous metal mines is affected by many uncertain factors difficult to describe mathematically with any level of *** problem can be solved by a synthesis of artificial *** on the analysis of the major factors affecting the scale of enlarged production,we first interpreted in detail the design principles and structure of the intelligent ***,we introduced an ANN *** order to ensure technological and scale efficien- cies of the training samples for ANN,we filtrated the samples with a DEA ***,we trained the intelligent system,which was proved to be very efficient.

关键词： non-ferrous metal mines production scale enlarge intelligent system ANN

f-Class Two Graphs Whose f-Cores Have Maximum Degree Two

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Acta Mathematica Sinica,English Series 2014年第4期30卷 601-608页

作者： Xia ZHANG gui Ying YAN Jian Sheng cai School of Mathematics Science Shandong Normal University Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematics and Information Sciences Weifang University

Abstract An f-coloring of a graph G is an edge-coloring of G such that each color appears at each vertex v ∈ V（G） at most f（v） times. The f-core of G is the subgraph of G induced by the vertices v of degree d（v） = f（v）maxv∈y（G）{ [d（v）/f（v）l}. In this paper, we find some necessary conditions for a simple graph, whose f-core has maximum degree two, to be of class 2 for f-colorings.

关键词： f-Coloring simple graph f-chromatic index f-class 2

Photochemical multicomponent transformation of acceptor-only diazoalkanes by merging their cycloaddition and carbene reactivities

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中国化学快报:英文版 2023年第9期34卷 138-142页

作者： Bao-gui cai Guo-Yong Xu Jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry&Chemical EngineeringAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials Ministry of EducationHefei 230601China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

Herein,we report an efficient photochemical method for the synthesis of poly-substituted pyrazoles through a multicomponent reaction of acceptor-only diazoalkanes,alkynes,and solvents(cyclic ethers or nitriles).The key to this success was driven by the photolysis of acceptor-only diazoalkanes to form free carbene species and the fast in situ[3+2]-cycloaddition formation of nucleophilic N–H pyrazole *** work also serves as an entry to allow future reaction design on the combination of carbene reactivity of diazoalkanes with their other reaction modes.

关键词： Photochemical synthesis Multicomponent reaction Diazoalkanes Carbene Pyrazoles

Influence of Aspect Ratio on Rolling Shear Properties of Fast-Grown Small Diameter Eucalyptus Lumber

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Journal of Renewable Materials 2020年第9期8卷 1053-1066页

作者： Tao gui Shichen cai Zhiqiang Wang Jianhui Zhou College of Materials Science and Engineering Nanjing Forestry UniversityNanjing210037China Integrated Wood Engineering University of Northern British ColumbiaPrince GeorgeV2L 1R7Canada

Eucalyptus is a major fast-grown species in South China,which has the potential for producing structural wood products such as cross-laminated timber(CLT).Aspect ratio(board width *** thickness)of eucalyptus lumbers is small due to the small diameter of fast-grown eucalyptus *** evaluate its rolling shear modulus and strength for potential CLT applications,three-layer hybrid CLT shear block specimens with different aspect ratios(2,4,6),were tested by planar shear test *** image correlation(DIC)was employed to measure the rolling shear strain distribution and development during the planar shear *** mean values of rolling shear modulus and strength of eucalyptus lamination were 260.3%and 88.2%higher than those of SPF(Spruce-pine-fir)lamination with the same aspect ratio of 4,*** rolling shear properties of eucalyptus laminations increased as the aspect ratio *** ratio had a significant influence on rolling shear modulus compared to rolling shear *** high shear strain regions were primarily found around the gaps between segments of cross *** quantity of high shear strain regions increased as the aspect ratio of lamination *** high shear strain regions also occurred around the pith and along the glue *** sudden failure of specimen occurred in the high strain *** conclusion,the rolling shear strength and modulus of fast-grown eucalyptus laminations exceed the respective characteristic values for softwoods in the current standard by roughly factors of 3 and 8,indicating great potential for fast-grown eucalyptus wood cross-layers in CLT.

关键词： Fast-grown eucalyptus cross-laminated timber rolling shear aspect ratio digital image correlation

亏缺灌溉对新疆不同品种春小麦产量和氮素利用的影响

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维普期刊数据库

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植物营养与肥料学报 2024年第5期30卷 886-898页

作者：车子强涂洪铭蔡静怡尹豪杰马熠琳蒋桂英石河子大学农学院新疆石河子832000

【目的】在水肥一体化条件下,研究不同生育期不同亏缺灌溉水平对春小麦产量和氮素利用的影响,为优化新疆春小麦水肥管理、提高小麦生产水肥效益提供技术支撑。【方法】于2022、2023年在石河子大学农学院实验站进行了管栽试验和小区试验... 详细信息

【目的】在水肥一体化条件下,研究不同生育期不同亏缺灌溉水平对春小麦产量和氮素利用的影响,为优化新疆春小麦水肥管理、提高小麦生产水肥效益提供技术支撑。【方法】于2022、2023年在石河子大学农学院实验站进行了管栽试验和小区试验,灌溉方式为滴灌。采用裂区设计,主区为干旱敏感品种新春22号(XC22)和耐旱品种新春6号(XC6);副区为灌溉处理,设置全生育期充分灌溉对照[CK,土壤湿度为田间持水量(FC)的75%~80%];分蘖期轻度亏缺(T1,60%~65%FC)、中度亏缺(T2,45%~50%FC);拔节期轻度亏缺(J1,60%~65%FC)、中度亏缺(J2,45%~50%FC)5个处理。调查了开花前后春小麦茎鞘、叶、穗及籽粒干物重、氮素含量,及成熟期小麦产量和产量构成因素;计算了花前氮素积累与转运、花后氮素吸收量及氮素利用率。【结果】两品种小麦成熟期植株氮素积累量(166.15~238.87 kg/hm^(2))、成熟期营养器官氮素分配率、各器官花前氮素转运量(21.76~57.66 kg/hm^(2))及其贡献率(14.15%~31.66%)、植株花前氮素转运量(78.67~147.66kg/hm^(2))及贡献率(51.58%~81.11%)均表现为T2、J2处理低于T1、J1,而T2、J2处理下籽粒氮素分配率、植株花后氮素吸收量及贡献率则高于T1、J1。亏缺灌溉处理下,品种XC6各器官氮素积累与分配、各器官花前氮素转运量及贡献率、产量及产量构成因素总体上高于干旱敏感品种XC22。与CK处理相比,T1处理下耐旱品种(XC6)成熟期植株氮素积累量显著提高了9.98%,茎鞘花前氮素转运量及贡献率分别提高了24.06%、18.91%,植株花前氮素转运量及贡献率分别显著提高了19.21%、12.53%,产量显著提高了12.17%,氮素利用率提高了2.25%,氮肥生产效率显著提高了12.16%,氮素收获指数提高了3.71%。而干旱敏感品种XC22的各项指标在4个亏缺灌溉处理下均低于CK。【结论】在新疆灌溉绿洲农业区,分蘖期轻度亏缺灌溉(60%~65%FC)可显著提高耐旱型春小麦花前氮素的积累量和向籽粒的转运,提高氮素利用率和氮素收获指数,并有效提高产量,进而达到节水高产的效果;而干旱敏感型品种不适宜于任何时期的亏缺灌溉。

关键词：春小麦亏缺灌溉氮素积累与转运产量形成氮素利用率

AN EXPERT CONTROL SYSTEM FORPURIFICATION PROCESS

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中国有色金属学会会刊：英文版 1996年第2期6卷 125-131页

作者： Wu, M gui, WH Xie, YF Shen, DY cai, ZX CENT S UNIV TECHNOL DEPT AUTOMAT CONTROL ENGNCHANGSHA 410083PEOPLES R CHINA

ＡＮＥＸＰＥＲＴＣＯＮＴＲＯＬＳＹＳＴＥＭＦＯＲＰＵＲＩＦＩＣＡＴＩＯＮＰＲＯＣＥＳＳＷｕＭｉｎ，ＧｕｉＷｅｉｈｕａ，ＸｉｅＹｏｎｇｆａｎｇ，ＳｈｅｎＤｅｙａｏ，ＣａｉＺｉｘｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＡｕｔｏｍ... 详细信息

ＡＮＥＸＰＥＲＴＣＯＮＴＲＯＬＳＹＳＴＥＭＦＯＲＰＵＲＩＦＩＣＡＴＩＯＮＰＲＯＣＥＳＳＷｕＭｉｎ，ＧｕｉＷｅｉｈｕａ，ＸｉｅＹｏｎｇｆａｎｇ，ＳｈｅｎＤｅｙａｏ，ＣａｉＺｉｘｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＡｕｔｏｍａｔｉｃＣｏｎｔｒｏｌＥｎｇｉｎｅ...

关键词： hydrometallurgical process of zinc process control expert systems expert optimization control distributed computer control systems

一种岩土边坡深层水泥搅拌桩用聚合物材料制备及特性分析

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粘接 2024年第2期51卷 92-95页

作者：桂阳蔡先庆赖君四川省交通勘察设计研究院有限公司四川成都610017 中铁二院工程集团有限责任公司四川成都610031

解决传统的岩土边坡深层水泥搅拌桩对水泥材料的依赖性较高,工程建设成本长期居高不下的问题。深层水泥搅拌桩是提高岩土边坡尤其软土边坡地基力学性能的重要手段,研究以粉煤灰-矿渣聚合物岩土边坡深层水泥搅拌桩为例,尝试利用粉煤灰-... 详细信息

解决传统的岩土边坡深层水泥搅拌桩对水泥材料的依赖性较高,工程建设成本长期居高不下的问题。深层水泥搅拌桩是提高岩土边坡尤其软土边坡地基力学性能的重要手段,研究以粉煤灰-矿渣聚合物岩土边坡深层水泥搅拌桩为例,尝试利用粉煤灰-矿渣等制备一种特殊聚合物水泥,对这种通过粉煤灰、矿渣等形成的聚合物原材料的综合性能进行分析。结果表明,当矿渣与粉煤灰的配合比为30∶70时,岩土边坡深层水泥搅拌桩的聚合物硬化时间最短,当碱浓度为2.5 mol/L时,能够获得最佳的材料压缩强度。

关键词：粉煤灰矿渣岩土边坡水泥搅拌桩性能分析