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991.
The effect of particle size distribution on the microstructure, texture, and mechanical properties of Al–Mg–Si–Cu alloy was investigated on the basis of the mechanical properties, microstructure, and texture of the alloy. The results show that the particle size distribution influences the microstructure and the final mechanical properties but only slightly influences the recrystallization texture. After the pre-aging treatment and natural aging treatment (T4P treatment), in contrast to the sheet with a uniform particle size distribution, the sheet with a bimodal particle size distribution of large constituent particles and small dispersoids exhibits higher strength and a somewhat lower plastic strain ratio (r) and strain hardening exponent (n). After solution treatment, the sheet with a bimodal particle size distribution of large constituent particles and small dispersoids possesses a finer and slightly elongated grain structure compared with the sheet with a uniform particle size distribution. Additionally, they possess almost identical weak recrystallization textures, and their textures are dominated by CubeND {001}<310> and P {011}<122> orientations.  相似文献   
992.
993.
Experimental study of partially flattened axial grooved heat pipes   总被引:1,自引:0,他引:1  
This article made experimental study on mini-axial grooved heat pipes (AGHP) with 11 flattening forms. It analyzed how the flattening form, flattening thickness and working temperature affect axial tamperature distribution, thermal resistance, heat transfer limit and the phase-change heat transfer coefficients in evaporator and condenser sections. The result indicates that all forms of AGHPs can maintain good isothermal performance under normal operating condition. The geometric shape of AGHP has obvious impact on heat transfer limit. With respect to an AGHP with 2 mm-thick evaporator section, when the thickness of its condenser section increases from 2 to 3 mm, its heat transfer limit Increases by 81%; with respect to an AGHP with 3 mm-thick evaporator section, when the thickness of its condenser section increases from 2 to 3 mm, its heat transfer limit increases by 134%; with respect to an AGHP with 4 mm-thick condenser section, when the thickness of its evaporator section increases from 2 to 3 mm, its heat transfer limit increases by 26%. When the thickness of the evaporator section increases by 1 mm, the heat transfer limit will increase by 9%-26%, while when the thickness of the condenser section increases by 1 mm, the heat transfer limit will increase by 20%-86%. The thickness of the condenser section has greater impact on heat transfer performance of an AGHP than the thickness of the evaporator section does. The study content of this article will help understand the heat transfer performance of AGHP, and electronic thermal design process.  相似文献   
994.
Thousand-grain weight (TGWT) is an important factor affecting grain yield as well as grain quality in rice. A quantitative trait locus (QTL) qTGWTI-1 for TGWT was detected previously near DNA marker RG532 on the short arm of chromosome 1 in a recombinant inbred line (RIL) population derived from the indlca-indica rice cross Zhengshan97B (ZS97B)/Milyang46 (MY46). In this study, two residual heterozygous lines (RHLs), Chl and Ch2, derived from the ZS97B/MY46 RIL F7 population, were used to develop two Fe populations, RIL-1 and RIL-2. The genome of Chl and Ch2 contains a heterozygous region flanked by RM1--RM3746 and RM151--RM243 on the short arm of chromosome 1, respectively, but is homozygous in other regions. Two tightly linked QTLs, Gwl-1 and Gwl-2, with the same additive direction and similar effect on TGWT, were detected in the region of QTL qTGWTI-1 in population RIL-2. No QTL was detected in the population RIL-1. Four individual RHLs from the population RIL-2 carrying heterozygous segments flanked by RM151--RM10404, RM10381--RM243, RM10435--RM259 and RM10398--RM5359, respectively, were chosen to develop four F= populations. Ten maternal homozygotes and 10 paternal homozygotes were selected from each of the four F2 populations derived from the four RHLs. The four sets of near isogenic lines (NILs) were grown for phenotyping of TGWT and delimitation of Gwl-1 and Gw1-2. Results showed that Gwl-1 and Gw1-2 were located in the intervals RM10376--RM 10398 and RM10404--RM 1344 which cover 392.9 and 308.5 kb regions, respectively. The enhancing alleles were from ZS97B at both loci, and no significant interactions were detected. Genetic dissection of Gwl-1 and Gwl-2 has laid a foundation for their cloning and molecular breeding of grain yield and quality in rice.  相似文献   
995.
【目的】为了降低二、三线城市中的零售商品物流配送系统的设计成本,提出一种电子地图功能的实现方案。【方法】参考桂林大成食品有限公司桶装水配送业务的实际运行环境,采用图形设备接口的升级版(GDI+)技术,在电子地图层上绘制不同颜色不同形状的图形及数字,以展示丰富的信息。【结果】基于本方案的物流配送系统在桂林市大成食品有限公司成功实施后,提高了公司的业务受理能力、配送服务质量和配送服务过程的控制能力。【结论】该方案能够提高物流配送系统信息的利用率。  相似文献   
996.
A novel phenol-linked bis(imidazolium) salt, H3LCl2 (L = O-4-C(CH3)3-C6H2-2,6-di[CH2{C(NCHCH- NAr)}]2, Ar = 2,6-diisopropylphenyl, 1), was designed and used to prepare an ionic iron(III) complex [H2L][FeCl4] (2). Complex 2 was a highly efficient catalyst for aryl Grignard cross-coupling of alkyl chlorides bearing β-hydrogens. Furthermore, complex 2 was reusable and could be reused in at least eight times without significant loss in catalytic activity.  相似文献   
997.
对二氧化钛的光催化降解有机物分子的原理进行了分析,综述了影响二氧化钛光催化效率的因素,及近年来提高二氧化钛光催化效率的各种方法及其原理。  相似文献   
998.
海上潜山油田压力监测系统优化研究   总被引:1,自引:0,他引:1  
井下压力计是获取地层压力的直接手段,每口井均下压力计能够全面取得地层压力参数,但增加了操作成本和油井管柱的复杂性。通过对JZ25-1N潜山油田压力分布、井位分布、构造特征等分析,综合考虑油田各井流动系数、产液、综合含水等参数对压力监测井位的影响,提出了海上潜山油田压力监测系统优化方法,并建立了数学模型。利用该方法优化了JZ25-1N潜山油田合理的压力计监测井位,定量分析压力监测井位以及压力监测井最小井数、比例等参数,所选取压力监测井位既代表了全油田的生产井和压力分布特征,又保持了合理的监测比例,实现了JZ25-1N潜山油田压力监测系统的优化部署。  相似文献   
999.
锅炉汽包疲劳寿命管理系统的研究   总被引:1,自引:0,他引:1  
介绍了锅炉汽包疲劳寿命管理系统的结构,软件特性及功能,运行情况表明,该管理系统可实时指导锅炉启动,提高锅炉启动的安全性与经济性,运用该系统,可提高电厂的生产和管理水平。  相似文献   
1000.
脱色剂与活性染料的分子间相互作用   总被引:16,自引:0,他引:16  
以聚丙烯腈(PAN)和双氰胺(DCD)为原料,合成了新型脱色剂.用IR、1 H NMR和13C NMR等方法对其结构进行了表征,探讨了脱色剂溶解度随pH 值变化的规律,研究了脱色剂对活性染料的絮凝脱色的性能.结果表明,脱色剂是侧链带有多种极性基团的聚合物;它在酸性条件下溶解度较小,碱性条件下溶解度较大;脱色剂对活性染料的脱色是有效的.在絮凝脱色研究基础上,用IR分析以及平衡渗析实验探讨了脱色剂与多种染料的相互作用.实验结果表明,脱色剂的絮凝效果在酸性条件下显著.相互作用研究显示,脱色剂分子侧链的氨基与活性染料的磺酸基发生了键合作用.脱色剂与蒽醌型活性染料的结合存在特殊的温度依赖性,结合程度在25℃最大;脱色剂与活性染料分子间除了极性基团间相互作用外,还存在疏水相互作用.  相似文献   
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