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1.
基于MATLAB的异步电动机线性化控制系统的仿真 总被引:1,自引:0,他引:1
从异步电动机在同步旋转坐标系下的状态方程出发,在一定的条件下,对其系数矩阵简化.推出异步电动机的线性化控制模型.并基于该模型得出异步电动机的线性化控制系统.以给定电机为例,对该模型的有效性、响应用MATLAB进行仿真分析.验证的结果说明上述模型具有实用价值. 相似文献
2.
CHEN Zhi-hong XU Li BA Xue-qing ZENG Xian-lu 《高等学校化学研究》2006,22(3):302-307
Introduction Migrationandrecruitmentofleukocytesfromblood toinflammatorylesionsitesaresequentiallyregulated byadhesionmoleculesandtheirreceptors[1].These lectinfamilyplaysamajorroleininitiatingattachement ofneutrophilstotheactivatedendothelium.P selectin,… 相似文献
3.
Mousa Z. Al-Noaimi Raid J. Abdel-Jalil Mustafa M. El-Abadelah Salim F. Haddad Younis N. H. Baqi Wolfgang Voelter 《Monatshefte für Chemie / Chemical Monthly》2006,37(12):745-750
In the presence of RuCl3, N-phenylamidrazone underwent oxidative cyclization into 1,4-dihydro-1-phenyl-1,2,4-benzotriazine, the structure of which is
established by spectral and X-ray diffraction data. 相似文献
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6.
A.H.N. Mousa 《Journal of fluorine chemistry》1985,30(1):29-35
A sample of benzotrifluoride was degassed in a high vacuum train, and the vapor pressure was measured in the temperature range 460 – 53OK. Also the saturated vapour and saturated liquid volumes were measured. Two simple equations were used to fit the vapour pressure data by the least square method. The heat of vaporization was calculated using Clapeyron equation. 相似文献
7.
The many fold aromatic ketones 2a‐d are versatile compounds for the synthesis of the many fold 1,2,3‐selenadiazole aromatic derivatives 5a‐d . The preparation starts with the reaction between the many fold bromomethylene benzene derivatives 1a‐d and 4‐hydroxyacetophenone, which are transformed through the reaction with semicarbazide hydrochloride or ethylhydrazine carboxylate into the corresponding semicarbazones derivatives 3a‐d or hydrazones 4a‐d . The reaction with selenium dioxide leads to regiospecific ring closure of semicarbazones or hydrazones to give the many fold 1,2,3‐selenadiazole aromatic derivatives in high yield. 相似文献
8.
M. A. Mousa 《Journal of Radioanalytical and Nuclear Chemistry》1987,118(1):33-43
The electrical conductivity and IR-spectra of pure and Cu-doped Fe3O4 spinels were measured at 300–1000 K. Two breaks in the conductivity-temperature curves have been observed for all investigated pure and doped samples. One of these two breaks were found near the Curie point of the investigated spinel. The electrical conduction in -irradiated and non-irradiated pure and Cu-doped Fe3O4 occurred by a hopping mechanism due to a fast electron exchange between Fe2+ and Fe3+-ions present on octahedral sites. The Seebeck-voltage of the irradiated and non-irradiated pure and Cu-doped samples has been measured. The effect of -irradiation on the conductivity values //, activation energy and type of defects was discussed. 相似文献
9.
The inhibition performance of five azomethine derivatives such as: 1-(4-Methyloxy phenylimino)-1-(phenylhydrazono)-propan-2-one (SB1), 1-(4-Methylphenylimino)-1-(phenylhydrazono) propan-2-one (SB2), 1-(phenylimino)-1(phenylhydrazono)-propan-2-one (SB3), 1-(4-Bromo phenylimino)-1(phenylhydrazono)-propan-2-one (SB4) and 1-(4-Chlorophenylimino)-1(phenylhydrazono) -propan-2-on (SB5) as corrosion inhibitors for mild steel in sulfuric acid 0.5 ?M were investigated using different methods. All experimental results demonstrate that these compounds are eficients inhibitors. The inhibition efficiencies () increase with inhibitors concentration. At 7.5 10?5 ?M, the was 97.27%, 96.31%, 94.23%, 93.19 and 91.64% for SB1, SB2, SB3, SB4 and SB5, respectively. The potentiodynamic polarization results indicated that all the studied inhibitors act as mixed type. The adsorption process on mild steel surface obeyed Langmuir isotherm. The associated activation parameters and thermodynamic have been calculated and discussed. The adsorbed film formed on the metal surface was characterized by SEM and EDX. 相似文献
10.
应用原子吸收光谱法测定了内蒙古地产的笃斯茎、叶中的Cu,Fe,Zn,Mn,Ca,Mg等六种人体必需微量元素及宏量元素的含量。从而为评价笃斯的品质及其药理、药效提供了具有一定价值的数据。 相似文献