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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan Qing-tao Guo Kai-lun Zhang Fu-zhi yu yu-ying Li yu-bao xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Impact of vegetation restoration on hydrological processes in the middle reaches of the Yellow River,China

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Forestry Studies in China 2009年第4期11卷 209-218页

作者： XIN Zhong-bao yu Xin-xiao Key Laboratory of Soil and Water Conservation and Desertification Combating of the Ministry of Education Beijing Forest Univer-sity 100083 P. R. China

Sediment discharge from the Yellow River originates mainly from the drainage area between Hekouzhen and Longmen, i.e., the Helong area. Spatial-temporal variations of the vegetation cover in this area during the 1981-2007 period have been investigated using GIMMS and SPOT VGT NDVI data. We have also analyzed the interannual variations in vegetation cover and changes in annual runoff and sediment discharge, the consequences from precipitation change and the Grain for Green Project （GGP）. The results show that vegetation cover of the Helong area has increased during the 1981-2007 period. The northwestern part the Helong area, where the flat sandy lands are covered by grass, has experienced the largest increase. The region where the vegetation cover has declined is largely found in the southern and southeastern Helong area, which is a gullied hilly area or forested. Although precipitation was relatively low during the 1999-2007 period, the vegetation cover showed a significant increase in the Helong area, due to the implementation of the GGP. During this period, the most significant improvement in the vegetation cover occurred mainly in the gullied hilly areas of the Loess Plateau, such as the drainage basins of the Kuyehe and Tuweihe rivers and the middle and lower reaches of the Wudinghe and Yanhe rivers. A comparison of the average annual maximum NDVI between the earlier （1998-2002） stage and the next five years （2003-2007） of the GGP indicates that the areas with increases of 10% and 20% in NDVI account for 72.5% and 36.4% of the total area, respectively. Interannual variation of annual runoff and sediment discharge shows a declining trend, especially since the 1980s, when the decrease became very obvious. Compared with the 1950-1969 period, the average runoff during the 1980-2007 period was reduced by 34.8 × 10^8 m3 and the sediment discharge by 6.4 ×10^8 t, accounting for 49.4% and 64.9% of that in the 1950-1969 period, respectively. There is a positive correlati

关键词： middle reaches of the Yellow River Hekouzhen to Longmen area (Helong area) vegetation restoration Grain forGreen Project (GGP) runoff and sediment

In-vitro Maturation of Immature Oocytes from Preantral Follicles in Prepuberal Mice

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Journal of Reproduction and Contraception 2007年第1期18卷 25-32页

作者： Min-zhi GAO yu-bao WANG xiao-yun WU Shanghai Institute of Planned Parenthood Research Shanghai Bokang Reproductive Hospital Shanghai 200032China

Objective To observe the morphological changes in in vitro growth of preantral follicle isolated from prepuberal mice and to assess impacts of gonadotropin （Gn）, insulin transferrin selenium （ITS） and epidermal growth factor （EGF） on their development. Methods Early preantral mice follicles （90-130μm diameter） were mechanical isolated and selected from 2 weeks＇ old mice and then cultured in alpha-minimal essential medium （α-MEM） with or without Gn, ITS and EGF. The preantral follicles were cultured singly in 20 miovliters droplets for up to 14 d. The medium was replaced and the .follicles were observed everyday. Granulosa cells （GC） prolification, antrum formation and oocyte maturation were recorded. Results The medium with Gn supported preantral follicle culture in vitro, during which they retained a three-dimensional structure, maintained oocytes viability and increased in diameter and number of somatic cells＇. Preantral follicles cultured in Gn medium grew obviously, while those without Gn grew slowly and after 6 d＇s culture began to shrink and blacken. Significant increase in survival rate and maturation rate of oocytes was observed in Gn group （P〈0.01）, with 92.9% survived and 28.7%formed an antrum. Further supplementation of the Gn medium with ITS and rLH, resulted in the significant increase in survival and maturation of preantral follicle （P〈0.05） Conclusions α-MEM can be the medium for in vitro culture （IVC） of preantral follicles, but need to be added with rLH/rFSH, rHCG/rEGF to facilitate thecal cell attachment, GC proliferation and oocyte maturation.

关键词： in vitro culture in vitro maturation follicle development

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非物质社会的互动式设计研究

深圳大学学报（人文社会科学版） 2006年第3期23卷 107-110页

作者：余晓宝深圳大学艺术与设计学院广东深圳518060

工业社会的物质文明向信息社会的非物质文明的转变,在一定程度上导致设计模式从单向的输出状态转化为双向的互动沟通。互动式设计不再以某种具有确定功能的产品作为创作的目的,而是以创建一个可供使用者自由选择和发展的平台为依归。它... 详细信息

工业社会的物质文明向信息社会的非物质文明的转变,在一定程度上导致设计模式从单向的输出状态转化为双向的互动沟通。互动式设计不再以某种具有确定功能的产品作为创作的目的,而是以创建一个可供使用者自由选择和发展的平台为依归。它所创造的体验具有多感官化、虚拟化、动态化、超现实化的特征。

关键词：非物质社会互动式设计体验

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数字形态的肌理研究

艺术百家 2005年第4期21卷 139-140,171页

作者：余晓宝深圳大学艺术与设计学院广东深圳518060

数字形态的肌理产生于电脑程序,在本质上是看不见的数字符号,但在看似杂乱无章的数字中间常常蕴涵着惊人的结果。分析归纳可知,数字形态肌理具有四种基本造型美学特征和三种生成规律。

关键词：数字形态肌理研究

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非物质社会中数字艺术设计的新方法

艺术百家 2006年第4期22卷 172-173页

作者：余晓宝深圳大学艺术与设计学院广东深圳518060

在工业社会的物质文明向信息社会的非物质文明的转变过程中,传统的设计方法、设计观念等不可避免地受到巨大的冲击和挑战,由此本文提出非物质社会中数字艺术设计的新方法:用服务的方式满足个性化需求、建立人-机交互平台满足沟通需求、... 详细信息

在工业社会的物质文明向信息社会的非物质文明的转变过程中,传统的设计方法、设计观念等不可避免地受到巨大的冲击和挑战,由此本文提出非物质社会中数字艺术设计的新方法:用服务的方式满足个性化需求、建立人-机交互平台满足沟通需求、用情感化的设计语言表达设计师的思想、运用网络实现设计资源的共享化增殖。

关键词：服务情感交互共享

Identification and Analysis of Genes Present in Leptospira interrogans serovar lai but Absent in L. biflexa serovar monvalerio

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 832-839页

作者： Ping HE, Xiang-Yan ZHANG, xiao-Kui GUO*, bao-yu HU, xiao-Tian HUANG, Yang YANG, and Guo-Ping ZHAO1,2* Department of Microbiology and Parasitology, Shanghai Second Medical University, Shanghai 200025, China 1 Research Center of Biotechnology, Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China 2Chinese National Human Genome Center at Shanghai, Zhangjiang High Tech Park, Shanghai 201203, China Department of Microbiology and Parasitology Shanghai Second Medical UniversityShanghai 200025 China Research Center of Biotechnology Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China Chinese National Human Genome Center at ShanghaiZhangjiang High Tech Park Shanghai 201203 China

Genes present in virulent bacterial strains but absent in avirulent close relatives can be of great biologic and clinical interest. This project aimed to identify strain specific DNA sequences of Leptospira interrogans serovar lai, which is absent in the saprophytic L. biflexa serovar monvalerio, via suppression subtractive hybridization with the former as the tester while the latter as the driver. The mixture of PCR amplified DNA fragments from two subtractive hybridization experiments were cloned into pMD18-T vector and the positive clones were identified by dot blotting against the chromosome DNA of the two strains individually. After DNA sequencing and analysis, the distribution of these genomic fragment sequences in a panel of pathogenic and nonpathogenic leptospires was investigated employing dot blot analysis. Among the 188 positive clones randomly chosen, 24 contained the tester strain specific genomic regions, of which, 5 were non-coding fragments while the others contained 23 distinct protein coding sequences. Besides 9 genes encoding functional proteins, 12 genes encode unknown proteins and the rest two genes encode proteins with recognizable domain structures, one for a putative leucine-rich repeats (LRR) family protein while the other as an outer-membrane protein. Our experiment results indicated that suppression subtractive hybridiza- tion is effective for screening specific DNA sequences between two leptospiral strains, and some of these sequences might be responsible for virulence determination. Further analysis of these DNA sequences will provide important information on the pathogenesis of Leptospira.

关键词： Leptospira interrogans serovar lai suppression subtractive hybridization (SSH) specific genes

铁死亡相关机制、调控手段及相关疾病研究进展

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中国药学杂志 2017年第4期52卷 253-257页

作者：曾杰陈玉宝徐晓玉西南大学药学院重庆400715

铁死亡(ferroptosis)是近年新发现的一种细胞死亡方式,其特征为细胞死亡过程中伴随着大量的铁离子累积和脂质过氧化。大量研究表明,该死亡方式与神经系统疾病、肿瘤、缺血再灌注损伤性疾病、肾损伤及铁代谢疾病等疾病密切相关,因此进行... 详细信息

铁死亡(ferroptosis)是近年新发现的一种细胞死亡方式,其特征为细胞死亡过程中伴随着大量的铁离子累积和脂质过氧化。大量研究表明,该死亡方式与神经系统疾病、肿瘤、缺血再灌注损伤性疾病、肾损伤及铁代谢疾病等疾病密切相关,因此进行铁死亡的机制及其调控药物研究也显得尤为重要。笔者对铁死亡的相关机制、诱导剂和抑制剂以及其相关疾病进行总结分析,以期为研究铁死亡更深入机制以及从该机制出发研制有效的治疗药物提供参考。

关键词：铁死亡铁离子累积脂质过氧化诱导剂抑制剂

计及火电调度的水电外送联盟利益均衡优化研究

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水电能源科学 2023年第10期41卷 77-81页

作者：喻小宝邓思维董真余上海电力大学经济与管理学院上海200090

当前,计及“双碳”目标影响的多能源联合外送联盟的利益分配问题亟待解决。在传统Shapley值法的基础上,考虑贡献公平性,引入资源投入、风险分摊、碳政策影响、贡献度四类指标,构建了基于云重心法改进的MCGC-Shapley模型,以四川省为例,... 详细信息

当前,计及“双碳”目标影响的多能源联合外送联盟的利益分配问题亟待解决。在传统Shapley值法的基础上,考虑贡献公平性,引入资源投入、风险分摊、碳政策影响、贡献度四类指标,构建了基于云重心法改进的MCGC-Shapley模型,以四川省为例,通过量化各主体的综合贡献度进行利益分配。算例分析表明,与传统Shapley值分配策略相比,基于云重心法改进的MCGC-Shapley模型更好地实现了主体所得利益与综合贡献度的匹配,对提高社会投资积极性、推动外送中各类发电企业和电网企业的多方共赢起到了正面作用。

关键词：水火打捆水电外送 Shapley值法云重心法利益分配

企业视角下新建本科高校理工科大学生就业问题研究

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景德镇学院学报 2019年第6期34卷 133-136页

作者：余小宝三明学院信息工程学院

随着社会对人才要求不断提高,高等教育的普及、大众化,新建本科高校理工科大学生求职难度年年增加。为了探寻影响新建本科高校理工科毕业生就业的因素,问卷调查S学院2018届理工科毕业生及部分用人单位,并运用spss22.0软件对用人单位问... 详细信息

随着社会对人才要求不断提高,高等教育的普及、大众化,新建本科高校理工科大学生求职难度年年增加。为了探寻影响新建本科高校理工科毕业生就业的因素,问卷调查S学院2018届理工科毕业生及部分用人单位,并运用spss22.0软件对用人单位问卷进行因子分析,在此基础上提出对策及建议。

关键词：新建本科高校理工科大学生就业因子分析