13 research outputs found

    Research on The Machining Technology of Lens Array Based on FTS and The Machining Equipment Development

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    科技的发展带动现代仪器朝着光、机、电一体化的微结构趋势发展,透镜作为一种重要的光学元件在民用和军用工业领域都有着广泛的应用。用于高精密仪器设备中的透镜不仅要有优越的光学性能,而且也要有微型化和高集成化的结构,因此透镜微结构中的代表——透镜阵列便应运而生。随着对透镜阵列的应用要求不断提高,传统透镜的加工方法已经很难适用于透镜阵列的加工,因此国内外将目光投向了新的超精密加工方法。其中,基于快刀伺服技术(FTS)的复杂微结构加工具有高频响、高定位精度和高加工精度等突出优点,已然成为微车削加工的主流技术之一。目前,国外许多国家已经成功运用该项技术加工出了高精度的透镜阵列元件,相关产品已应用于工业领域,...Precision technology now develops very quickly. The development of technology requires the integration of the light, machine, electricity, lens as an important optical components into the modern instruments in civil industry and military industry areas. High-precision instruments and equipment requires the lens to have not only superior optical performance but also structure of miniaturization an...学位:工学硕士院系专业:物理与机电工程学院_机械工程学号:1992011115272

    Effects of electropuncture of acupoints on the foot Yangming stomach meridian on metabolic profiling of gastric mucosa in gastric ulcer rats

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    目的:采用核磁共振氢谱技术(1H; NMR)研究电针胃经穴对应激性胃溃疡大鼠胃黏膜组织代谢物谱的表达。方法:40只SD大鼠随机分为正常组、模型组、胃经组和胆经组。利用束缚-冷应激法; 制备应激性胃溃疡模型大鼠,光镜下观察大鼠胃黏膜组织病理形态学的变化,采用1H NMR技术获取胃黏膜组织1H; NMR谱,并利用模式识别方法分析各组间的代谢物谱的差异。结果:与正常组比较,模型组大鼠胃黏膜损伤和胃黏膜组织代谢轮廓差异明显,胃黏膜组织乙酸、肌; 醇、磷酸胆碱、谷氨酸、甘氨酸、乙醇胺、赖氨酸、3-羟基丁酸、缬氨酸、异亮氨酸、牛磺酸、亮氨酸和甘露醇含量上升(P<0.05),乳酸、甲硫氨酸和天; 冬氨酸含量下降(P<0.05);与模型组比较,胃经组和胆经组大鼠胃黏膜得到明显修复,胃经组大鼠胃黏膜组织代谢轮廓更接近正常大鼠,胃黏膜组织甲硫氨; 酸、天冬氨酸含量上升(P<0.05),乙酸、肌醇、磷酸胆碱、谷氨酸、甘氨酸、赖氨酸、异亮氨酸、牛磺酸、乳酸、亮氨酸和甘露醇含量下降(P<0.05; );胆经组大鼠胃黏膜组织3-羟基丁酸、甲硫氨酸含量上升(P<0.05),肌醇、磷酸胆碱、谷氨酸、乙醇胺、异亮氨酸、乳酸、亮氨酸和甘露醇含量下降(; P<0.05)。结论:电针胃经穴可调节胃溃疡大鼠胃黏膜组织特异代谢物的表达,促进胃黏膜损伤的修复。Objective: To research the effects of electropuncture of acupoints on; the foot Yangming stomach meridian on metabolic profiling of gastric; mucosa in rats of gastric ulcer induced by stressusing the 1H nuclear; magnetic resonance (1H NMR). Methods: Forty SD rats were randomly; divided into the control group, the model group, the stomach meridian; group and the gallbladder meridian group. The rat model of gastric ulcer; was induced by the restrained plus cold stress. The pathological changes; in the rat gastric mucosa tissue were observed by light microscope. The; 1H NMR spectroscopy was determined with the 1H NMR technique. And,; meanwhile the differences in the metabolic profiling were identified; with the pattern recognition method. Results: Compared to normal group,; the gastric mucosa damage and gastric mucosa metabolic profiling are; obvious, the concentration of acetic acid, choline, inositol phosphate,; glutamic acid, glycine, ethanolamine, lysine, 3-hydroxy butyric acid,; valine, isoleucine, taurine, leucine and mannitol increase and the; concentration of lactic acid, methionine and aspartic acid decrease in; model group rats (P<0.05). Compared to model group, the gastric mucosa; damage have been recovered in stomach meridian group and gallbladder; meridian group, the metabolic profiling of gastric mocusa tissue in; stomach meridian group are similar to the normal group. The; concentration of methionine, aspartic acid increase and acetic acid,; choline, inositol phosphate, glutamic acid, glycine, lysine, lactic; acid, leucine, isoleucine, taurine, and mannitol decrease in stomach; meridan group (P<0.05). The concentration of 3-hydroxy butyric acid,; methionine increase and choline, inositol phosphate, lactic acid,; leucine, isoleucine, glutamic acid, ethanol amine and mannitol decrease; in gallbladder meridian group (P<0.05). Conclusion: The electropuncture; of acupoints on the foot Yangming stomach meridian could regulate the; metabolic profiling of gastric mucosa, resulting in improving the; gastric mucosa repair of gastric ulcer rats.国家自然科学基金项目; 国家重点基础研究发展计划(973计划)项目; 广东省自然科学基金项目; 深圳市科技计划项

    Isolation and Characterization of a H2 -producing Strain Enterbacter sakazakii HP

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    通讯作者 Tel 0592-2185731, E-mail: longmn@ xmu.edu.cn[中文文摘]在自然环境中分离到一株具有高产氢活性的微生物菌株,经细菌鉴定仪及16S rRNA基因序列分析,鉴定该菌株为Enterbacter sakazakii HP。分析了起始pH值、反应温度、碳源、起始糖浓度、起始氧浓度及菌体密度等因素对菌株产氢活性的影响。研究表明,该菌株发酵产氢较适合的条件为:以葡萄糖为产氢底物,起始pH值8.0,菌体密度OD600=0.7,反应温度35℃,糖浓度为0.1mol/L,氧浓度为0%的条件下,此时产氢菌株的最高产氢活性为5.34μmolH2/h.mgdw,氢的得率为1.94molH2/mol葡萄糖。[英文文摘]A H2 -producing bacterial strain was newly isolated and identified as Enterbacte sakazakii HP by 16S rDNA sequence analysis and detection by BBLCRYSTAL AUTOREADER.Various factors,including substrates and its concentration,initial pH,temperature and oxygen,on the hydrogen production of E.sakazakii HP have been studied extensively.Among several sugars,glucose was the favorite substrate for hydrogen production.The optimum condition for hydrogen production by Enterbacte sakazakii HP was achieved as:initial pH8.0,cell density OD600 =0.7,temperature 35℃,glucose concentration 0.1 mol/L,oxygen concentration 0%.Under batch fermentative hydrogen production conditions,the maximal hydrogen production activity and hydrogen yield were obtained as 5.34μmol H2 /h·mg dw and 1.94mol H2 /mol glucose,respectively.The research results suggest that Enterbacter sakazakii HP is an ideal candidater for biological hydrogen production.国家自然科学基金项目(No30470395);厦门市科技项目(No3502Z20041070);厦门大学新世纪优秀人才计划项目;福建省青年科技人才创新项目(No2005J003

    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

    Biohydrogen Production from Rice Straw by Simultaneous Saccharification and Fermentation Using Klebsiella oxytoca HP1

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    氢作为一种清洁的能源引起了人们的普遍重视.实验以产酸克雷伯氏菌(Klebsiella oxytoca)HP1为产氢菌株,以稻草粉为产氢底物,进行同步糖化发酵(Simultaneous Saccharification and Fermentation,SSF)产氢.对影响同步糖化发酵产氢的单因子进行试验,选取对氢产率影响较大的因子:温度、pH、纤维素酶用量等进行L9(34)正交试验.结果表明同步糖化发酵产氢的最佳条件为:温度40℃,pH6.5,纤维素酶用量为20FPAU/g稻草粉,摇床转速100r/min,发酵时间42h.在该条件下的最大氢产率为110.6mL/g稻草粉,稻草粉的氢转化率为22%.进行了10L放大发酵产氢试验,最大氢产率为122.3mL/g稻草粉,氢转化率为24.3%.与分步糖化发酵(Separate Hydrolysis and Fermentation,SHF)产氢相比,氢产率提高34.4%.研究表明,利用同步糖化发酵工艺可以提高生物制氢的产量和得率.Being regarded as a clean energy source,biological hydrogen attracts more and more attention.Hydrogen production from rice straw by simultaneous saccharification and fermentation (SSF) was studied using the Klebsiella oxytoca HP1 in this report.The experiments of batch ferment hydrogen production were carried out in 600 mL serum bottles.Single factor and orthogonal experiments showed that the optimal conditions for hydrogen production were:pH6.5,ferment temperature 40℃,cellulose dose 20 FPAU/g rice straw,revolution 100 r/min and ferment time 42 h.The maximum H2 production (110.6 mL/g rice straw) and H2 yield efficiency (22%) were obtained under the above conditions.The enlarge experiments were carried out in a 10 L bioreactor,a maximum H2 production of 122.3 mL/g rice straw and a H2 yield efficiency of 24.3% were achieved.The H2 production increased by 34.4% compared with the separate hydrolysis and fermentation hydrogen production.This research indicated a perfect application of SSF in biohydrogen production from cellulose material.国家自然科学基金项目(30470395);; 厦门市科技项目(3502Z20041070);; 厦门大学新世纪优秀人才计划项目(X07114)资
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