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81.
电解法处理利福霉素SV钠废渣分离液的研究   总被引:2,自引:0,他引:2  
刘瑛  王娉 《工业水处理》2002,22(2):30-31
根据电化学原理,采用电解法,利用铁屑与炭粒作电极,处理利福霉素SV钠药渣分离液,讨论各种因素对分离液污染物作效果的影响,COD去除率可达91.8%左右,脱色率可达95%左右。  相似文献   
82.
This essay concentrates on two key procedures of image mosaic--image registration and imagefusion.Becauseof the character of geometric transformation invariance of edge points, wecalculate the angle difference of the direction vector ofedge points in different images anddraw an angle difference histogramto adjust the rotationproblem. Through this way, algorithm based on gray information is expandedandcan be used in images withdisplacementand rotation. Inthe term of image fusion, wavelet multi-scale analysis is used to fuse spliced images. In order to choose the best method of imagefusion,weevaluate the results of different methods of image fusion by cross entropy.  相似文献   
83.
Novel composite particles based on nanoscale calcium carbonate (nano‐CaCO3) as the core and polyacrylates as the shell were first synthesized by in situ encapsulating emulsion polymerization in the presence of the fresh slush pulp of calcium carbonate (CaCO3) nanoparticles. Subsequently, these modified nanoparticles were compounded with rigid poly(vinyl chloride) (RPVC) to prepare RPVC/CaCO3 nanocomposites. At the same time, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were investigated, and the synergistic effect of modified nanoparticles with chlorinated polyethylene (CPE) was also studied. The results showed that in the presence of nano‐CaCO3 particles, the in situ emulsion polymerization of acrylates was carried out smoothly, and polyacrylates successfully encapsulated on the surface of nano‐CaCO3 to prepare the modified nanoparticles, breaking down nano‐CaCO3 particle agglomerates, improving their dispersion in the matrix, and also increasing the particle–matrix interfacial adhesion. Thus, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were very significant, and the cooperative effect of the nanoparticles with CPE occurred in the united modification system. Scanning electron microscopy analyses indicated that large‐fiber drawing and network morphologies coexisted in the system of joint modification of nanoparticles with CPE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3940–3949, 2007  相似文献   
84.
水蒸气蒸馏法提取广西百色地区迷迭香茎、叶中的挥发油,利用GC-MS联用仪进行了分析。共分离出36个峰,鉴定了其中31个化学成分,占总含量的97.08%。其主要成分为1,8-桉叶素、α-蒎烯、樟脑、莰烯、α-松油醇、乙酸龙脑酯及龙脑等。  相似文献   
85.
In numerous physical processes involving the motion of micron and submicron sized particles near surfaces, such as the filtration of hydrosols and aerosols, the particle motion is the net result of the combined effects of fluid convection, external forces, particle inertia, Brownian particle motion, and particle-surface fluid dynamic interactions. The most general method of describing particle motion under the combined action of these effects is through the so-called Fokker-Planck equation. In the absence of particle-surface fluid dynamic interactions, the Fokker-Planck equation is well-known, and it has been applied in a general way to problems involving the adsorption or deposition of Brownian particles onto surfaces through a solution technique known as the Brownian dynamics simulation method.

In this study, the Fokker-Planck equation for Brownian particle motion near surfaces is generalized to include particle-surface fluid dynamic interactions. The Fokker-Planck equation is shown to follow from the Liouville equation for the Brownian particle and n-fluid molecules present in the system, thus, establishing a firm theoretical foundation for the Fokker-Planck equation and the various other phase-space diffusion equations that follow from it.

Based on diagonalization of the Fokker-Planck equation, its short-time behavior is also derived here which enables a generalization of the Brownian dynamics method for the study of particle motion near surfaces including fluid dynamic interactions. Additionally, a perturbation solution of the Fokker-Planck equation under the conditions of small, but finite particle Stokes number is also derived. These solutions are shown to agree with previously given representations of the Smoluchowski or convective-diffusion equation for Brownian particle motion near surfaces, as well as with inertial corrections to the Smoluchowski equation available in the literature. This latter equation is also generalized here to include particle-surface fluid dynamic interactions.  相似文献   
86.
87.
从跨文化交际角度,分析了中式英语在词汇层面上的三种表现形式:望文生义、词汇冗余和文化词汇误用.认为中式英语的形成与思维方式差异和文化差异直接相关.  相似文献   
88.
采用分子动力学方法模拟了不同截面尺寸金纳米线的拉伸力学行为。计算结果表明:相同长度的金纳米线弹性模量随着截面尺寸的减小而减小,而其屈服强度随着截面尺寸的减小而增大,并且发生屈服推迟现象。应力—应变曲线与形变过程相对应。在弹性变形阶段,纳米线形变不显著;随着应变量的增加,发现纳米线出现大量堆垛层错。  相似文献   
89.
The existing equivalent methods usually only deal with static load models and neglect the dynamic characteristics of loads such as induction motors.This paper presents a dynamic equivalent method which considers motor dynamics.At first,the clustering criterion of motor loads is given.The motors with similar dynamic characteristics are classified into one group.Then,reduction of motors in the same group is carried out.Finally,parameters of the equivalent motor are calculated and the equivalent system is thus...  相似文献   
90.
研制成功的声频谱测井仪器在井下发射和接收三种频率的声波信号,其中发射和接收20kHz声波信号的声系有一个发射和四个接收探头,源距为2.1~2.568m,间距为0.156m;发射和接收40kHz声波信号的声系由一个发射和两个接收探头组成,源距1.0—1.5m,间距0.5m;发射和接收10kHz声波信号的声系由一个发射和两个接收探头组成,源距为2.168—2.668m,间距0.5m.用三种不同的频率的声波进行测量记录目的是获得井壁径向深度不同处介质的声学信息,而且不同频率的声波信号在岩石中传播过程中频谱变化也是井壁岩层的可用声学信息.在井下的信息采集、数据传输、地面记录和监控全部由计算机控制.该仪器已经在大庆油田的三口井中成功的进行了野外实验.  相似文献   
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