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排序方式: 共有1354条查询结果,搜索用时 15 毫秒
1.
锰粉料制块是解决铁合金冶炼精料入炉的主要途径之一,生产过程中为解决锰粉料粘附计量斗的问题,介绍了一种新型计量斗,阐述他的结构特点和工作原理,实施改进后下料流畅,降低了劳动强度,提高了生产效率。  相似文献   
2.
The effect of lomefloxacin was studied on mice with experimental infection due to Mycobacterium tuberculosis. The antibiotic was administered in doses of 100 and 200 mg/kg. It was shown that the use of lomefloxacin for a month provided a lower death rate of the animals with progressing acute generalized tuberculosis, a lower level of the lesions in the internal organs and a lower number of the Mycobacterium isolates from them. The efficacy of the treatment depended on the drug dose. When lomefloxacin was used in a dose of 200 mg/kg, the survival rate was much higher and the number of the epithelial unicellular granulomas in the tissue of the lung and spleen was markedly decreased while with the lower dose the indices did not differ from those in the control.  相似文献   
3.
The proposed models for irreversible finite deformation of initially anisotropic solids are based on the hypothesis of the parameters of state, for which the authors have chosen a universal parameter (temperature) and a strain component, which is analogous to volume strains in an isotropic body and represents thermal strains of an unconstrained (stress-free) anisotropic solid. The application of this hypothesis allows the strain tensor to be resolved into a reversible and irreversible components. For irreversible processes of finite deformation of hardenable materials, the authors have proposed a deformation-type model, which makes it possible to describe a change in the type of anisotropy of initially anisotropic materials in the course of deformation. For the flow-theory-type model, the limiting state function, as given in the space of irreversible strains, allows for the experimentally observed plastic flow of anisotropic crystals under the action of hydrostatic pressure only.  相似文献   
4.
The rate of absorption of amino acids obtained from isolated krill protein administered to rat stomach was studied. Absorption of casein amino acids was determined for reference purposes. Rats subjected to 48-hour fasting were administered krill isolate and casein in the form of homogenates at a rate 540 mg protein per 100 g bw in 6 ml of distilled water. The concentration of free amino acids in the portal vein was measured after 30 minutes, 1, 3 and 6 hours. The content of amino acids was measured by ion-exchange chromatography with the use of an automatic analyzer of amino acids. The digestion of krill protein proceeds at a high rate. This ensures the maximal augmentation of the concentration of most amino acids in the blood of the portal vein 30 min after isolate administration to the stomach.  相似文献   
5.
The indirect immunofluorescent technique was used to study the distribution of the ascitic fluid antigen (AgD) on histological sections from surgical specimens of gastric and colon tumours from proximal to distal lines of resection. AgD was found in gastric tumours exceptionally in the tumour area and in colon cancer--both in the tumour stroma and in surrounding histologically normal mucosa.  相似文献   
6.
Eight diazoles were investigated as corrosion inhibitors of mild steel in 1 M hydrochloric acid using gravimetric and polarization techniques. It was found that the inhibition efficiency increased with the increase of organic substrate concentration, while the adsorption followed the Frumkin isotherm. A correlation between the electronic parameters (induction and mesomeric effects of the substituents, ionization potential values) as well as those of the chemical structure (molecular area) of diazoles molecules and their inhibiting properties was looked for. The results obtained show that a definite interdependence exists but it is not as simple and straightforward as might be expected.  相似文献   
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8.
With the aim of classifying PVC materials in which surface layers are converted into interpenetrated network cyclam nanofilms among polymer-polymer systems, comparative studies of their properties were carried out with consideration for the specific conditions for the preparation of the material. The density and structures of near-surface layers, the bulk ratio of the ordered and disordered forms, the dynamics of swelling in water, and the effective partial volume occupied by water molecules were studied for PVC plates prior to and after hydrothermal treatment. The conversion of the surface layers changes the structural self-organization of PVC: the polymer structure becomes more compact and ordered both in the area adjacent to the nanofilm and in the polymer bulk, which is characteristic of systems of the type “hard coating on soft substrate”. Original Russian Text ? A.Ya. Fridman, E.M. Morozova, A.Yu. Tsivadze, N.P. Sokolova, I.I. Bardyshev, A.M. Gorbunov, O.P. Shapokhina, 2007, published in Zashchita Metallov, 2007, Vol. 43, No. 5, pp. 498–502.  相似文献   
9.
This article proposes an approach for investigating the exponential stability of a nonlinear interval dynamical system with the nonlinearity of a quadratic type on the basis of the Lyapunov’s direct method. It also constructs an inner estimate of the attraction domain to the origin for the system under consideration.  相似文献   
10.
全面预算管理过程是一个管理循环过程,它包括预算编制、预算执行、预算控制、预算考评4个环节,各环节管理质量的高低导致了预算实施结果的差异。从4个环节入手,讨论了各管理环节在具体工作中方法的运用及需注意的细节。最后强调,一个企业全面预算管理工作顺利实施的重要保障是预算管理组织机构的建立与相配套的领导者素质。  相似文献   
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