内承式钢筒仓内承钢架的优化设计

对内承式钢筒仓的内承钢架的优化设计进行了理论分析，并给出计算程序框图和计算示例。     

Near time optimal control with perturbation estimation for flexible spacecraft slewing maneuvers

1.INTRODUCTION Inrecentyears,therehasbeenconsiderableinterest inmodelingandcontrolofflexiblespacecraft.Thisis contributabletotheuseoflightweightandslender materialsforthespeedandfuel efficiencypurposes. Inmanyapplications,sophisticatedcontrolalgo rithmsarerequiredtomakeoptimaluseofmaximum torqueavailablefortimeminimizationmaneuvers, thistimeminimizationcontroloftenresultsinabang bangcontrolthatcanbeimplementedinaerospaceap plicationsusingon offthrusterjetstechnology.But unfortunately,t…     

SH6型转换锁闭器底壳的加工

文章主要介绍了SH6型转换锁闭器重要零件--底壳的加工工艺过程,包括工艺路线的制定、工艺结构分析、工装设计、使用中的注意事项、刀具和切削参数的选择方面等内容,着重分析了机加工过程中的重点、难点,并对影响加工精度的外在和内在因素进行了归纳分析.总结了加工底壳类零件的一些方法和经验.     

点燃文学激情提高人文素养——初中文言文复习策略探究

文言文博大精深,如何让学生主动地、快乐地投入到文言文复习中,提高复习效率,是语文教师长期探索的一大难题.实践证明,采用课本剧编演和擂台赛的形式复习能点燃学生学习文言文的激情,运用比较迁移拓展方法复习,激活学生的知识积累,引导学生根据中考考点梳理文言文知识,会更进一步提升学生水平,真正达到学以致用的目的.     

纳米硫化铜与明胶蛋白质的直接键合作用

在pH=12.0的明胶溶液中,采用一锅化学反应法制得水溶性明胶/CuS纳米生物复合物.利用透射电子显微镜(TEM)、X射线粉末衍射(XRD)对复合物进行表征,显示纳米CuS颗粒为球状且表面被明胶大分子包覆.紫外-可见吸收光谱(UV-Vis)和傅里叶红外光谱(FT-IR)表明CuS与明胶肽链的酰胺基键合;CuS与明胶的键合,对明胶内源荧光有着较强的猝灭作用,为静态猝灭过程.由修正的Scatchard公式模型求出复合物的表观形成常数,结合位点数以及反应的热力学参数(△rHm=37.88kJ·mol-1;△rSm=216.77J·K-1·mol-1;△rGm=-57.44/-58.98/-60.69kJ·mol-1),结果表明反应是自发进行(△rGm0),且为熵驱动(△rSm0).     

高精度频率型集成化温度传感器的研制

介绍一种高精度频率型集成温度传感器，２．５～３Ｖ电源，３２～４４℃温度范围内测温精度为±０．１℃，特别适合于生物医学测温使用．集成芯片的频率输出信号可以直接送微处理器．文中还提出了可重组和参数可调的集成传感器的多功能设计     

Extraction and Purification of Matrix Protein from the Nacre of Pearl Oyster Pinctada fucata

A soluble matrix protein P14 with an apparent molecular mass of 14.5 kDa was isolated from fragmented nacre of pearl oysters （Pinctada fucata） treated with 10% NaOH solution to investigate the nacre matrix proteins and their effect on the CaCO3 crystal. The protein was characterized by gel exclusion chromatography and reversed-phase high performance liquid chromatography after demineralization by 10% acetic acid. The X-ray diffraction pattern of P14 crystals indicates that P14 plays an important role in nacre biomineralization. P14 can induce aragonite formation, stimulate CaCO3 crystal formation, and accelerate aragonite precipitation. Heating of the acid insoluble nacre residue, which was named conchiolin, in 10% sodium dodecyl sulfate solution supplemented with 10% β-mercaptoethanol solution for 10-20 min at about 100℃ gave two other soluble proteins having molecular masses of 19.4 kDa and 25.0 kDa. The present study suggests that these two proteins are linked to the insoluble organic matrix by disulfide bridges because the extraction yield increases when β-mercaptoethanol is added to the medium.