HPLC Method for the Determination of Tamsulosin Hydrochloride in Sustained Release Tablets

The development and validation of an isocratic high performance liquid chromatographic method is de-scribed for the determination of tamsulosin hydrochloride in sustained release tablets. The determination was per-formed on a Diamonsil BDS C18 column with a mobile phase consisting of a mixture of acetonitrile, methanol and 0.5% phosphoric acid solution (20:30:50, V/V/V) at a flow rate of 1.0 mL/min. UV detection was made at 274 nm. The linear range for tamsulosin hydrochloride was 0.81 - 8.10μg/mL. The mean recovery was 99.8%(SR = 0.7 %, n = 9), and the precision was found to be 0.45 % ( n = 9). The proposed method can be used for routine analysis of tamsulosin hydrochloride in sustained release tablets.     

A New Calculating Method for the Flowfield of Turbomachinery

In this paper, a new method is developed to solve the N-S equations with vorticity-velocity variables, which is suitable for describing the flow-field of turbomachinery in non-inertia coordinates. It is derived that the expansions of the vorficity-velocity equations (VVE)have the same form in arbitrary non-orthogonal curvilinear coordinates, because the non-inertia effect is only related to the initial and the boundary conditions. This method greatly simplifies the solution for the flowfield of turbomachinery with complicated geometrical domain and reduces the calculation cost.     

Triboelectrostatic Separation-anEfficient Method of Producing Low Ash Clean Coal

1　 IntroductionActive carbon has been used in fields ofmedicine,food,environmental protection,mili-tary,and so on,because it has a developed innerspace and a tremendous specific surface area.Thepresent active carbon produced from coal is in itslow- grade because of the high ash contentof feed-stock coal.To deeply remove ash and producelow- ash ( <3% or <2 % ) clean coal is the keystep to produce high- grade coal- base active car-bon.At present,the wet processing is the mainmethod of fine coal…     

Electrorheological Properties of Suspensions of PAn-PEO-PAn Triblock Copolymer Particles

The PAn-PEO-PAn triblock copolymer with the PEG chain length of 400 was synthesized by chemical oxidation copolymerization of aniline and α,ω-bis（p-aminophenyl）poly（ethylene glycol）and characterized by FT-IR and TEM.The experimental results show that the copolymer particles are of μtypical core-shell structure after the self-assembly process in water.Its conductivity is much lower than that of the pure PAn.The suspension containing 20 vol% PAn-PEO-PAn tiblock copolymer in silicone oil exhibits.a typical electrorheological （ER） effect in DC electric field.while it shows a lower leakage current density than that of the pure PAn-based ER fluids.Therefore,the PEO shell hinders the electric hop among PANI chains and decreases the current density of ER fluids in an external electric field.at the same time the interface polarity improves the ER effects.     

Determination of the Micro Stress Field in Composite by Homogenization Method

1 IntroductionThe stresses in composite determined by taking thecomposite as macro homogeneous material is in fact thenominal stresses or effective stresses . They can only re-flect the response of the composite to external macro en-vironments but not the effects of micro heterogeneity.Forcomposites are widely used as high qualitystructure mate-rials that have to satisfy strict engineering requirements ,detailedinformation of stress distribution is necessary forstructural designand optimizatio…     

Synthesis of MnZn Ferrite Nanoscale Particles by Hydrothermal Method

ＭｎＺｎｆｅｒｒｉｔｅｓａｒｅｗｉｄｅｌｙｕｓｅｄｉｎｅｌｅｃｔｒｏｎｉｃａｐｐｌｉｃａ ｔｉｏｎｓｓｕｃｈａｓｔｒａｎｓｆｏｒｍｓｃｈｏｋｅｃｏｉｌｓａｎｄｎｏｉｓｅｆｉｌｔｅｒｓｂｅ ｃａｕｓｅｏｆｔｈｅｉｒｈｉｇｈｅｒｐｅｒｍｅａｂｉｌｉｔｉｅｓａｎｄｌｏｗｍａｇｎｅｔｉｃｌｏｓｓ ｅｓａｔｈｉｇｈｆｒｅｑｕｅｎｃｉｅｓ .Ｔｈｅｉｒｐｒｏｐｅｒｔｉｅｓｌａｒｇｅｌｙｄｅｐｅｎｄｓｏｎｔｈｅｉｒｍｉｃｒｏｓｔｒｕｃｔｕｒｅ .[1]Ｓｏｔｈｅｎａｎｏ ｔｅｃｈｎｉｑｕｅｗｅｒｅｉｎ ｔｒｏｄｕｃｅｄｔ…     

Structure and Infrared Radiation Properties of Substituted Cordierites

Zn^2＋ - or Ti^4＋ -substituted cordierites with the nominal compositions of Mg1 .6 Zn0.4 Al4 Si5 O18 and Mg1.8 Ti0.2 Al4.4 Si4.6 O18 respectively, were prepared by a conventional solid state reaction method. The structure of the substituted eordierites was characterized by X- ray diffraction （ XRD ）, infrared （ 1R ） spectroscopy and 29 Si magic angle spinning （ MAS ） nuclear magnetic resonance （ NMR ）. The infoared radiation properties were investigated in the bands within 2.5-25μm. Compared with the na-substituted cordierite composition （ Mg2 Al4 Si5 O18 ）, Zn^2＋ - or Ti^4＋ -substituted cordierites show superior infrared properties. XRD and IR results confirm the formation of hexagonal a-eordierite as the main eo＇stal phase for the substituted cordierites. 29 Si MAS NMR result indicates that Zn^2＋ or Ti^4＋ Substitutions for partial Mg^2＋ of a-eordierite promoted the ordering of the distribution oral and Si atoms in T1 （ tetrahedra connecting six-raembered rings together with [ MgO6] octahedra ） and T2 （ tetraheda forming six-reentered rings） tetrahedral sites. This resulted in a lattice deformation and increased the anharmonicity of polarization vibration, which is responsible for the improvement of infrared radiation properties of the substituted eordierites.     

Tribological Properties of PVA-H Composites Reinforced by Nano-HA Particles

The friction and wear behaviors of tribological mechanical components were studied on a four-ball tester under dry conditions, and the wear mechanism was analyzed by observed worn surface using a scanning electron microscope （SEM）. It was found that the friction and wear properties were improved by the addition ofnano HA particles. The composite containing 1 wt% nano HA had the optimum friction coefficient. It is also found that the addition of nano HA increases the wear resistance of oure PVA-H and PVA-H composites.     

Magnetic Properties of NiCuZn Ferrite Thin Films Prepared by the Sol-gel Method

Ni0.4Cu0.2Zn0.4Fe2O4 thin films were fabricated on Si substrates by using the sol-gel method and rapid thermal annealing （RTA）, and their magnetic properties and crystalline structures were investigated. The samples calcined at and above 600 ℃ have a single-phase spinel structure and the average grain size of the sample calcined at 600 ℃ is about 20 nm. The initial permeability μi, saturation magnetization M and coercivity H of the samples increase with the increasing calcination temperature. The sample calcined at 600 ℃ exhibits an excellent soft magnetic performance, which has μi=33.97 （10 MHz）, Hc=15.62 Oe and Ms=228.877 emu/cm^3. Low-temperature annealing can enhance the magnetic properties of the samples. The work shows that using the sol-gel method in conjunction with RTA is a promising way to fabricate integrated thin-film devices.     

A Method of Wide Convergence Region for Solving Inverse Problems of Wave Equations

ＡＭｅｔｈｏｄｏｆＷｉｄｅＣｏｎｖｅｒｇｅｎｃｅＲｅｇｉｏｎｆｏｒＳｏｌｖｉｎｇＩｎｖｅｒｓｅＰｒｏｂｌｅｍｓｏｆＷａｖｅＥｑｕａｔｉｏｎｓＬＩＵＪｉａｑｉ；ＱＩＡＮＪｉａｎｌｉａｎｇ；ＨＡＮＢｏ刘家琦，钱建良，韩波（Ｄｅｐｔ．ｏｆＭａｔｈｅｍａｔｉ...     

计算小尺度封闭空间内混响时间的方法研究

混响时间是描述封闭声场内声音衰减快慢程度的物理量，也是音质设计中的一个重要客观评价参数。文中基于封闭空间内声有限元模型．提出了一种计算小尺度封闭空间内任意位置混响时间的方法。该方法弥补了赛宾公式不能准确求解非扩散声场内混响时间的缺陷。另外，对于尚处在设计阶段的小尺度封闭空间．由于无法通过测量获得混响时间，文中也为封闭空间内进行虚拟音质设计提供了计算混响时间的方法。给出了描述小尺度封闭空间内声场的有限元模型；在该模型的基础上推导了计算小尺度封闭空间内混响时间的方法．并编制了相应的计算机程序；在算例部分．计算了一矩形封闭空间内的混响时间，通过与实验结果进行比较，验证了这一方法的正确性。     

Ni超微粉制备工艺的正交试验设计

在制备金属超微粉时，其产率与电弧电流、气氛比例及水平气流等诸多因素有关为提高产率，需确定出某种金属超微粉的最佳制备工艺为此，采用了正交设计试验方法，较好地解决了影响因素与试验次数之间的矛盾     

A Structure Similarity Analysis Method for On－Line Recognition of Handwritten Chinese Characters

ＡＳｔｒｕｃｔｕｒｅＳｉｍｉｌａｒｉｔｙＡｎａｌｙｓｉｓＭｅｔｈｏｄｆｏｒＯｎ－ＬｉｎｅＲｅｃｏｇｎｉｔｉｏｎｏｆＨａｎｄｗｒｉｔｔｅｎＣｈｉｎｅｓｅＣｈａｒａｃｔｅｒｓＬＩＵＪｉａｆｅｎｇ；ＴＡＮＧＪｉａｎｇｌｏｎｇ；ＳＨＵＷｅｎｈａｏ（刘家锋，唐...     

松散土状矿石样品小体重测定方法的校正

在松散土状矿石样品的体重测定中,目前使用较多的是传统的小体重测定法,受样品含水率、孔隙度以及体积变化的影响,存在测定值普遍偏低、误差较大的问题,直接影响矿物原料储量计算的准确性.针对这个问题,在分析传统小体重测定法局限性的基础上,通过引入全排水干体重和实排水干体重两个新的概念,提出了一种体重校正方法,包括样品的加水重塑造型方法和确定自然含水率方法,并以一个随机抽取松散土状矿石样品为例,对该校正方法的合理性进行了验证,结果证明该校正方法是合理和有效的.该校正方法应用到大批量样品的体重测定中并计算矿产储量,比用传统方法计算得到的矿产储量有显著提高.     

A Differential Continuation－Regularization Method for Solving Inverse Problems of Acoustic Wave Equations

ＡＤｉｆｆｅｒｅｎｔｉａｌＣｏｎｔｉｎｕａｔｉｏｎ－ＲｅｇｕｌａｒｉｚａｔｉｏｎＭｅｔｈｏｄｆｏｒＳｏｌｖｉｎｇＩｎｖｅｒｓｅＰｒｏｂｌｅｍｓｏｆＡｃｏｕｓｔｉｃＷａｖｅＥｑｕａｔｉｏｎｓ￥（张大力）（韩波）（刘家琦）（姜立功）ＺＨＡＮＧＤａｌｉ；Ｈ...     

Restraint on the Effect of Friction by Localization Method

ＲｅｓｔｒａｉｎｔｏｎｔｈｅＥｆｆｅｃｔｏｆＦｒｉｃｔｉｏｎｂｙＬｏｃａｌｉｚａｔｉｏｎＭｅｔｈｏｄ￥（胡恒章）（傅丽）ＨＵＨｅｎｇｚｈａｎｇ；ＦＵＬｉ（Ｄｅｐｔ．ｏｆＣｏｎｔｒｏｌＥｎｇｉｎｅｅｒｉｎｇ，ＨａｒｂｉｎＩｎｓｔｉｔｕｔｅｏｆＴｅｃｈｎ...     

等效小参量法求解强非线性系统的有效性研究

文章在已有研究的基础上,通过对不同失真度的非线性系统进行求解和比较,得出结论:等效小参量法对于失真度达到30%左右的非线性系统分析是有效的.同经典的扰动法相比较,在非线性较弱时,等效小参量法和扰动法一样能获得精确的结果,但是,在非线性较强时,等效小参量法表现出比较明显的优势.     

无先验信息的小批量生产质量控制图动态优化

针对日益发展的小批量生产模式的质量控制,在样本数据无先验信息条件下,提出了一种基于随机加权法的质量控制图参数优化方法.采用随机加权法对样本数据进行再抽样,估计样本数据的分布参数(样本均值和方差),经假设检验,动态优化质量控制图的控制参数弥补了小样本条件下传统控制图的不足,实现了无先验信息下小批量生产过程的质量控制.实验表明,优化后的控制图的控制参数更加逼近于理论值,优于传统控制图的控制参数,适合用于小批量生产环境下的质量控制.     

小型水库渗漏病害并行电法测试应用

近年来使用中的小型水库坝体因病害产生的事故在不断增多,所开展的库坝异常诊断需要得到加强。目前,地球物理方法已被广泛应用到水库坝体病害勘察中,但受不同方法限制,其探查的灵敏点不同。发生的病害主要是坝体渗漏引起的坝基失稳问题,电阻率法可以发挥重要的作用。文章采用并行电法采集技术,利用小极距高密度采样并综合反演,可以对大坝渗漏等异常位置较为准确探查与预报。现场实践结果表明,并行电法在大坝探查中具有一定的优势,适宜于中小型土石坝病害诊断与分析。