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251.
本文根据物理尺度的区域分解法[1],[2],从奇异摄动的观点把解分为外部解和边界层校正,两者在固定的物面边界上藕合,这样对不同的尺度区域,可用不同的简化方程及计算方法.本文给出了人工压缩N-S方程的特征性质及其合适的边界提法,计算的例子表明,精度和效率是满意的.  相似文献   
252.
张可佳  周德和  顾群  徐修容 《色谱》1994,12(2):95-97
应用毛细管区带电泳(CZE)分析测定阿片受体、抗独特型抗羟甲芬太尼抗体等生物大分子样品。熔融石英毛细管柱为60cm×100μmi.d.(从进样到检测器长度为50cm),以硼砂-氢氧化钾为缓冲液。结果表明缓冲液的pH影响CZE对阿片受体的分析,当pH为9.0时分析效果最理想,重现性良好,测得的两个主峰与同批样品进行SDS-PAGE分析得到的两个条带相符。用CZE分析抗独特型抗羟甲芬太尼抗体(IgG),表明用PrOteinA-Sepharose亲和色谱分离得到部分纯化的IgG,迁移时间不同于对照豚鼠的IgG。  相似文献   
253.
IntroductionChaedcyclodextrlnswerefirstIntroducedby几rabelforchlralseparationofamlnoacids,andthechargedCDcommonlyusednowdaysarecarboxymethyl-p-CD(CM-p-CD),p-CD-phosphate,Y-CD-phosphate,sulfobutylether-p-cyclodextrln(SBE-p-CD)etc....  相似文献   
254.
圆盘状裂纹前缘塑性区尺寸及张开位移估计   总被引:1,自引:0,他引:1  
将Dugdale模型推广到三维裂纹问题计算了圆盘状裂纹前缘塑性区尺寸,并结合断裂力学中的Barenblatt-Dugdale裂纹模型和三维J-积分原理计算了圆盘状裂纹前缘张开位移,得到了J-积分与裂纹张开位移的关系,最后用非线性有限元方法对圆盘状裂纹的前缘塑性区尺寸作了数值分析,确定了公式中的未知常数,并对其正确性作了数值验证,本文的工作推广了Dugdale模型的应用范围。  相似文献   
255.
陈勇  杨新  韩凤梅  袁倬斌 《分析化学》1999,27(6):694-696
研究了影响毛细管区带电泳激光诱导荧光间接检测环腺苷单磷酸和环鸟苷单磷酸的实验条件.cAMP和cGMP的线性范围分别为30~500mg/L和15~500mg/L,其最低检测限分别为9.0mg/L和0.5mg/L;当浓度为125mg/L时,cAMP和cGMP峰面积的RSD为4.45%和6.21%(n=4);其迁移时间的日间RSD分别为2.92%和2.04%(n=5)  相似文献   
256.
A self-consistent problem of interaction of two dipole atoms separated by an unrestricted distance with the field of a quasi-resonance light wave was solved on the assumption that the investigated atoms are Lorentz linear oscillators and the polarizing fields inside the system consist of the Coulomb and the retarded parts. The solution obtained was investigated for the case where the atoms have the same polarizability and the distance between them is much smaller than the length of the external light wave. Formulas for the electric fields inside a small object and outside it have been obtained. It is shown that inside a small two-atom object there can take place longitudinal and transverse optical vibrations accompanied by corresponding dispersion effects depending on the interatomic distance and the angle between the axis of the system and the direction of propagation of the external light wave. The field outside the small object in the wave zone is linearly polarized when the external wave has linear polarization. However, the direction of polarization of the corresponding waves is largely determined by their frequency. It is also shown that the amplitude of the field outside the small object in the wave zone depends greatly on the frequency of the external field and the interatomic distance. The effects observed are considered as a near-field effect in optics of small objects. This phenomena makes it possible to investigate the structure of small objects with the use of optical radiation. Ul'yanovsk Branch of the Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 48 Goncharov Str., Ul'yanovsk, 432700, Russia; e-mail: gadomsky@quant.univ.simbirsk.su. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6, pp. 765–770, November–December, 1999.  相似文献   
257.
The article surveys the main unsolved problems of the electronic structure of nonmetals in a wide energy region of fundamental absorption. Udmurtia State University, 71, Krasnogeroiskaya Str., Izhevsk, 426034, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 3, pp. 299–315, May–June, 1999.  相似文献   
258.
Disodium 5′-ribonucleotide, which is composed of disodium 5′-inosine (IMP) and disodium 5′-guanosine (GMP), is an important food additive. The lack of kinetic studies of it causes a lack of clarity in understanding the complicated multi-solute crystallization of IMP + GMP in ethanol-water. In this work, process analytical technology tools were used to obtain the thermodynamics and kinetic data from the experiments, the kinetic parameters of anti-solvent and cooling crystallization were investigated. The crystal form of IMP + GMP mixed crystal was determined, which was consistent with the IMP whether crystallized from pure water or ethanol-water. The effects of different anti-solvent addition rates and cooling rates on the metastable zone widths were studied, and the opposite effect on metastable zone width was found. The modified exponential empirical function was developed to correlate nucleation and growth kinetic equations under different conditions. The kinetic data were well fitted with adjusted correlation coefficient (adj-R2 > 0.7), which is sufficient to provide a valid reference for process design and control.  相似文献   
259.
运用Stokes公式及边界元理论,导出了辐射换热计算中的辐射角系数与相互辐射面积的计算基本公式。通过四个典型例子的计算,结果与精确解加以对比,表明本方法计算可靠、稳定,具有输入数据少,准确度高等优点。分析了影响计算准确度有关因素,对所遇到的奇异积分给予了有效的处理。  相似文献   
260.
This paper presents a numerical study of radiative heat transfer in a floating zone (FZ) furnace which was performed by using the commercial finite element program FIDAPTM. This resistance furnace should provide a temperature higher than the melting temperature of silicon (i.e. Tmax ≈ 1500 °C) and a variable temperature gradient at the liquid/solid interface (≥ 25 K/cm). Due to the high working temperatures, heat radiation plays the dominant role for the heat transfer in the furnace. For this reason, the quality of view factors used in the wall‐to‐wall model was carefully inspected with energy‐balance checks. A numerical model with two control parameters is applied to study the influence of material and geometrical parameters on the temperature field. In addition, this model allows us to estimate the internal thermal conditions which were used as thermal boundary conditions for partial 3D simulations. The influences of an optical lens system on the radial symmetry of the temperature field were examined with these partial 3D simulations. Furthermore, we used the inverse modeling method to achieve maximum possible temperature gradients at the liquid/solid interface according to the limitation of maximum available power and the maximum stable height of a melt zone.  相似文献   
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