30 research outputs found

    Applied research of the buoyancy regulating system on work AUV

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    本文根据我国正在研制开发的作业型水下机器人的特性及其对浮力调节和姿态控制的要求,应用PID控制策略,设计了一个浮力调节系统,仿真结果证明该设计方案可以达到预期的目标。(100039北京市中国科学院研究生院)常海

    Optimizing Process Algorithm and Calculating Data Points of the Skirt Part of Piston that Combination of Elliptical Part and Eccentric Circular

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    二次椭圆-偏心正圆活塞在车用活塞领域得到了越来越广泛的应用,但加工精度普遍较低.详细介绍了二次椭圆-偏心正圆活塞的形状特征,并建立二次椭圆-偏心正圆活塞的数学模型.为了提高此类活塞的加工精度,运用变截面螺旋线轨迹算法,在此基础上,通过MATlAb生成二次椭圆-偏心正圆活塞的加工轨迹点坐标.More and more piston that combination of elliptical part and eccentric circular used in vehicle,but the machining accuracy is generally low.This paper introduce the features of piston that combination of elliptical part and eccentric circular and build the mathematical model of piston that combination of elliptical part and eccentric circular.In order to improve the machining accuracy of this piston,we adopt the variable cross-section helix turning trajectory algorithm,then generate the machining trajectory point coordinates of piston that combination of elliptical part and eccentric circular by MATLAB.国家自然科学基金(51275433;51075343

    生物活性材料CS浸提液调控人胚胎干细胞的功能

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    目的:人胚胎干细胞(hESCs)是再生医学和生物医药应用的重要的潜在细胞来源。目前在体外有多种因素可以诱导hESC定向分化,包括生长因子、诱导剂、抑制剂等,其中calcium silicate(CS)是一种具有生物活性的硅酸钙陶瓷材料,可以促进细胞的活性、增殖、黏附、分化和基因表达,其富含Si~(2+)的浸提液还可以促进细胞的成骨、成血管分化。目前已知CS浸提液对多种干细胞都具有促进分化的作用,但是它对ESC的生物学表型的影响还不

    涡分辨率海洋模式模拟的印度尼西亚贯穿流

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    干旱地区改良粘质土壤的绿化技术

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    本发明提供的干旱地区改良粘质土壤的绿化技术,步骤的实施:一是挖去原土60-100cm;二是在底部铺设砾石层20-30cm;三是在砾石上铺设土工布,制作土工布的孔洞数不少于8-12个/平方米,直径2-3厘米为宜;四是在土工布的上层客入耕作土40-70cm即可。耕作土中砂石含量应小于15%,不得含有大于25mm的石砾及杂物,土壤总盐量应小于2.2ms/cm,pH值小于8.5。该技术适合面状换土改造,不适合穴状换土改造,同时要求地下水埋深不小于1米。本发明针对粘质土壤的改良,在充分解析盐渍化发生机理的基础上,采取该绿化技术,从根本上解决绿化地土壤盐渍化和次生盐渍化问题,并保证绿化的长期效果,工期短,成本低,可操作性强。2006-2008年试种植的草坪及乔灌木树种,三年连续成功,充分验证了该绿化技术在干旱地区的应用推广的价值及实用性

    双亲金属卟啉跨膜转移的控制

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    Research on smelting ingredient diluting for refined copper strip by bacteria foraging optimization algorithm

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    During the smelting process of refined copper strip production, to reduce varied losses caused by obvious superscales of some individual ingredients, the multi-charge diluting optimization method for smelting ingredients of refined copper strips is studied. The multi-object optimization model for smelting ingredients diluting is established. Lagrangian relaxation idea is introduced to transform the multi-objective model, and the detail implement steps of bacteria foraging optimization (BFO) algorithm are designed to solve above model. The experiment result shows that BFO algorithm is suitable for solving complex optimization problems such as diluting smelting ingredient. © 2010 IEEE

    采用代谢流量分析方法评估二噁英对细胞的代谢干扰

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    以肝癌细胞HepG2为供试细胞,选用5个不同浓度的二噁英(0、0.001、0.01、0.1和1.0 nmol.L~(-1)),探讨2,3,7,8-TCDD对HepG2细胞的毒性效应.采用90%甲醇离心法实现蛋白与代谢产物的分离,建立了高效液相色谱-串联三重四极杆质谱(HPLC-MS/MS)分析胞外液中的23种代谢产物(20种氨基酸、乳酸、甘油和尿素)的方法.建立的HPLC-MS/MS分析方法对各化合物的加标回收率可达91%—105%之间,化合物浓度的标准偏差均小于10%.在此基础上,结合代谢流量分析系统研究了2,3,7,8-TCDD对HepG2细胞内代谢流的影响.结果表明,随着浓度的增高,2,3,7,8-TCDD对HepG2细胞代谢的干扰作用呈增强趋势.2,3,7,8-TCDD降低了细胞对葡萄糖的吸收,并进一步抑制了HepG2细胞糖酵解的速率.此外,2,3,7,8-TCDD导致了HepG2细胞乳酸代谢流的明显增加,由此使细胞产生了过量的乳酸
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