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Search Results: 1 - 10 of 53213 matches for " 付学中 "
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高校微生物学实验课考核内容和方法的创新研究
,黄运红,
微生物学通报 , 2007,
Abstract: 微生物学实验是高等院校生命科学及其相关专业的一门基础必修课。在创新实验教学内容的基础上,对微生物学实验课的技能考核内容与方法进行了一系列探索,实践表明,在学期末进行微生物学实验技能考核对提高微生物学实验教学质量具有重要意义。
噬菌体抗体库的构建及抗乳腺癌细胞单链抗体的筛选
赵岩??, 王清明*, , 陈吉, 范国才, 陈惠鹏
生物工程学报 , 2004,
Abstract: 构建抗人乳腺癌细胞mcf7的噬菌体单链抗体库,从中筛选mcf7细胞特异性单链抗体。用mcf-7细胞免疫balbc小鼠,取脾脏,提取总rna,用rt-pcr技术扩增小鼠抗体重链(vh)和轻链(vl)可变区基因,经重叠pcr(soe-pcr),在体外将vh和vl连接成单链抗体(scfv)基因,并克隆到噬菌粒载体pcantab5e中,电转化至大肠杆菌tg1,经辅助噬菌体超感染,构建噬菌体单链抗体库。从该抗体库中筛选特异性识别mcf-7细胞的噬菌体单链抗体,将表面展示单链抗体的单克隆噬菌体转化大肠杆菌top10进行可溶性表达。成功地构建了库容为12×106的抗mcf-7乳腺癌细胞的单链抗体库,初步筛选到了与mcf7细胞特异性结合的scfv,westernblot检测表明,在大肠杆菌top10中实现了单链抗体可溶性表达
面齿轮副小轮拓扑修形设计及啮合性能分析
,方宗德,李建华,蒋进科
哈尔滨工程大学学报 , 2016, DOI: 10.11990/jheu.201506074
Abstract: 为改善面齿轮啮合性能,设计了小轮齿廓、齿向修形曲线,将3次B样条拟合的修形曲面与小轮理论齿面叠加构造精确的拓扑修形齿面,建立了小轮拓扑修形面齿轮副TCA、LTCA计算模型,并试验验证了理论分析的正确性。算例分析表明:小轮拓扑修形能获得开口向下2阶抛物线几何传动误差,接触路径与齿根倾斜,较传统面齿轮副,有效重合度提高了约10%,容差能力提高了400%;各载荷下承载传动误差波动幅值均减小,齿面载荷分布变化均匀,轮齿进入和退出啮合时承受载荷变小。
偏置面齿轮安装误差容差性与敏感性
,方宗德,向龙,李建华,崔艳梅
哈尔滨工程大学学报 , 2018, DOI: 10.11990/jheu.201612082
Abstract: 为确定偏置面齿轮安装误差工艺参数,本文建立了含安装误差偏置面齿轮副的通用啮合坐标系和齿面接触分析算法。基于TCA获取的齿面接触印痕,提出了采用安装误差公差表征容差性、采用参考接触点位置和接触迹线方向角偏移量表征敏感性的分析方法。应用Matlab软件进行了程序化并仿真,分析表明:轴夹角误差最敏感,容差性最差,而偏置误差最不敏感,容差性最好,实际安装调整时要严格控制轴夹角误差;右齿面的容差性比左齿面好,且偏置距越大,右齿面容差性越好,左齿面容差性越差;安装误差使齿面参考接触点位置主要在齿宽方向移动,而在齿高方向变化不大,且左、右齿面的参考接触点位置偏移量变化规律相同,但左、右齿面的接触迹线方向角偏移方向相反。
采用NSGA-Ⅱ算法的面齿轮副小轮 拓扑修形多目标优化
NSGA-Ⅱ Based Multi??Objective Optimization on Topologically Modified Pinions for Face Gear Pairs

,方宗德,关亚彬,李建华
- , 2017, DOI: 10.7652/xjtuxb201707015
Abstract: 为合理确定面齿轮副小轮的修形参数,设计了均由2段抛物线与1段直线组成的直齿小轮齿廓和齿向修形曲线,将由三次B样条拟合得到的修形曲面与理论齿面相叠加来构造拓扑修形齿面。采用带精英策略的快速非支配排序遗传算法(NSGA-Ⅱ),结合面齿轮副的几何接触分析(TCA)和承载接触分析(LTCA)技术,提出了以修形曲线参数为优化变量,使抛物线几何传动误差曲线两端对称、接触印痕限制在齿宽中部、承载传动误差波动幅值最小的小轮拓扑修形多目标优化设计方法,并编制了相应的Matlab程序。算例表明:优化修形参数后得到了对称的抛物线几何传动误差和位于大轮齿宽中部的接触印痕,并大幅度减小了承载传动误差波动,从而可有效降低安装误差敏感性和齿轮副的振动、噪声。
To reasonably determine the technical parameters in profile modification of face gear pairs, a tooth profile and an axial modification curve both composed of two sections of parabola and a straight line on a spur pinion are created. A topologically modified tooth surface can be represented as a superposition of theoretical tooth surface and the deviation surface obtained by cubic B??splines fitting on the tooth surface grid. Based on the tooth contact analysis (TCA) and loaded tooth contact analysis (LTCA) of the face gear pairs, taking the parabolic transmission error curve being symmetrical in geometry, the contact path being limited in the central tooth width, and the minimum wave amplitude of loaded transmission errors as the three optimization objectives, a multi??objective optimization model is established, and the corresponding programs are developed by software Matlab. The fast elitist non??dominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ) is selected as the multi??objective optimization algorithm. An optimization example shows that the present method obtains symmetric parabola geometry transmission error and the contact path in the middle of gear tooth width, which greatly reduces the wave amplitude of loaded transmission errors, hence effectively reduces installation error sensitivity, vibration and noise
面齿轮传动全齿面闪温分布与抗胶合修形优化
Full Tooth Surface Flash Temperature Distributions and Anti??Scuffing Optimization of Tooth Modification for Face Gear Drives

,方宗德,崔艳梅,彭先龙,李建华
- , 2018, DOI: 10.7652/xjtuxb201811018
Abstract: 为快速求解面齿轮传动的全齿面闪温分布,基于Blok闪温公式、齿面接触分析和承载接触分析技术,通过计算接触椭圆长轴离散点处的切向速度、综合曲率半径、载荷密度以及赫兹接触带半宽,建立了面齿轮传动全齿面闪温求解模型,并与带精英策略的快速非支配排序遗传算法相结合,以小轮修形曲线的8个参数为优化变量,以全齿面闪温最小为优化目标,建立了面齿轮传动抗胶合修形优化模型。算例分析结果表明:节线附近闪温近似为0℃;离节线越远,相对滑动速度就越大,闪温也越大,胶合失效最易发生在啮出的接触椭圆长轴上;优化小轮修形参数使全齿面的最大闪温下降了29.9%,从而提高了面齿轮传动的抗胶合能力。
To rapidly calculate the full tooth surface flash temperature distributions of face gear drives, following Blok flash temperature formula, tooth contact analysis and loaded tooth contact analysis technology, a calculating model for full tooth surface flash temperature distribution of face gear drives is established by evaluating the tangential velocity comprehensive curvature radius of the discrete points on contact ellipse long axes load density and semi??width of the Hertzian contact band. Combining with the fast elitist non??dominated sorting genetic algorithm II, an antiscuffing optimization schedule of tooth modification for face gear drives is constructed by regarding eight parameters of curves on modified pinions as the optimization variables and the minimum tooth surface flash temperature as the optimization objective. The calculations examples show that the flash temperature on the contact ellipse long axes near the pitch cone approaches 0℃, the farther the contact ellipse long axis from the pitch cone, and the higher the sliding velocity and flash temperature on the contact ellipse long axis, the scuffing failure is more prone to occur on the mesh??out contact elliptical long axis. Once optimizing the modification parameters of the pinion, the maximum tooth surface flash temperature decreases by 29.9%, thus improving the antiscuffing capacity of face gear drives
镁铝混合氧化物负载镍催化剂上液化石油气的预重整
王新星,广,尚兴,聂望欣,邹秀晶,鲁雄钢,丁伟
催化学报 , 2012, DOI: 10.3724/SP.J.1088.2012.20138
Abstract: ?采用共沉淀-浸渍法并在较低温度(400~700oC)下焙烧制备了镁铝混合氧化物(MgmAl)负载的Ni催化剂.X射线衍射和程序升温还原结果表明,Ni物种高度分散于催化剂表面,没有形成尖晶石NiAl2O4.在650oC可被还原成金属Ni纳米晶粒,在400oC和较低水/碳摩尔比(S/C=2)条件下表现出较好的催化液化石油气(LPG)重整反应性能.详细考察了Mg/Al摩尔比、Ni负载量、载体和催化剂的焙烧温度对催化剂活性和稳定性的影响.结果表明,由500oC焙烧的Mg1.25Al载体负载的15%Ni催化剂,并于500oC焙烧时,在LPG重整反应中表现出最优的性能,尽管它比高温(≥800oC)焙烧制备的Ni/MgmAl催化剂更易积炭,催化活性和稳定性有所下降,但由于还原温度较低,在交通和小规模供电的燃料电池领域更具实际应用意义.
Isolation and Identification of a Strain of Micromonospora with Broad-spectrum Antimicrobial Activity
一株具有广谱抗菌活性小单孢菌的分离和鉴定

LONG Zhong-Er,ZHU Yue-Jin,HUANG Yun-Hong,FU Xue-Qin,
,朱跃进,黄运红,

微生物学通报 , 2008,
Abstract: A rare strain of actinomycetes, with broad-spectrum antimicrobial activity, was isolated from the soil samples from the farmland in the area of Yaohu lake in Nanchang. The information about the taxonomic identification, such as the morphology, physiological properties, cell components and 16S rRNA gene sequences, suggested that the rare strain of actinomycetes was identified as Micromonospora carbonacea.
Isolation and Purification of Antibiotic from the Fermentation Broth of Micromonospora carbonacea JXNU-1 and Its Physical-chemical Properties
炭样小单孢菌JXNU-1广谱抗生素产物的分离及其理化性质

LONG Zhong-Er,ZHU Yue-Jin,HUANG Yun-Hong,FU Xue-Qin,
,朱跃进,黄运红,

微生物学通报 , 2008,
Abstract: 基于实验室自行分离到的一株具有广谱抗菌活性的炭样小单孢菌JXNU-1,研究了该菌株广谱抗生素产物的分离纯化工艺及其部分理化性质.结果表明,该茵产生的抗生素在中性和碱性条件下具有极高的热稳定性,但在酸性条件下不稳定.发酵液通过离心、过滤的预处理过程后,抗生素可吸附到717型阴离子交换树脂上,经2 mol/L的NaCl溶液洗脱除杂,再用20%的乙醇洗脱,可得抗生素产物,且在20%的乙醇溶液中加入2 mol/L的NaCl,可大大提高抗生素的洗脱效率.抗生素的酒精--盐洗脱液经减压浓缩去酒精、透析除盐后可得抗生素的水溶液.该抗生素水溶液经纸层析分析仅检测到单一活性斑点,HPLC分析表明其纯度达到99%以上.所得抗生素在Molish反应,Benedict反应扣二苯胺反应中均呈现阳性,紫外吸收具有典型的核苷类物质的光吸收特征,推测该抗生素为一核苷类抗生素.
Isolation and Identification of a Strain of Micromonospora with Broad-spectrum Antimicrobial Activity
一株具有广谱抗菌活性小单孢菌的分离和鉴定

LONG Zhong-Er,ZHU Yue-Jin,HUANG Yun-Hong,FU Xue-Qin,
,朱跃进,黄运红,

微生物学报 , 2008,
Abstract: A rare strain of actinomycetes, with broad-spectrum antimicrobial activity, was isolated from the soil samples from the farmland in the area of Yaohu lake in Nanchang. The information about the taxonomic identification, such as the morphology, physiological properties, cell components and 16S rRNA gene sequences, suggested that the rare strain of actinomycetes was identified as Micromonospora carbonacea.
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