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41.
The thermal treatment by millimeter waves for the soil disinfection can be one possible alternative to chemical treatments. This physical method is based on incrementing the soil temperature and its pathogens irradiating with high frequency electromagnetic waves. So the previous knowledge of the temperature distribution in the irradiated soil is essential for achieving an effective bad microorganism and weed seeds elimination. This report analyse the heating kinetic and spatial distribution of the maximum temperatures reached by the soil. It is presented a mathematic model about how are distributed the reached temperatures in the depth of the irradiated soil. This model concludes that when an orchard soil is irradiated superficially by microwaves, the microwaves have a big attenuation due to the soil dielectric properties and the water located in the pores of the most superficial layer. This fact causes a shield effect blocking the waves penetration in few centimetres. The heating by radiation is reduced to the superficial layer. The heating propagation in the depth is occurred by conduction following the Fourier equations.  相似文献   
42.
The oxidation of aminoethanethiol (1) was investigated in acid solutions on a glass carbon anode. It was shown that at relatively low anode potentials thiyl radicals RS· are released into the solution, but this does not lead to binding of the oxygen in the solution. Raising the anode potential leads to binding of oxygen, which is probably due to the formation of the intermediate RS+. The oxidation of 1 was studied in Ce(SO4)2+H2SO4 solution. It was shown that under certain conditions the intermediate is RS+, which subsequently converts to a product that could not be identified as any previously described product of the oxidation of thiols. Proposals are made regarding its structure and conversion pathways.B. P. Konstantinov Institute of Nuclear Physics, Russian Academy of Sciences, 188350 Leningrad. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 278–288, February, 1992.  相似文献   
43.
As a consequence of Jensen's inequality, centered operators of probabilistic type (also called Bernstein-type operators) approximate convex functions from above. Starting from this fact, we consider several pairs of classical operators and determine, in each case, which one is better to approximate convex functions. In almost all the discussed examples, the conclusion follows from a simple argument concerning composition of operators. However, when comparing Szász-Mirakyan operators with Bernstein operators over the positive semi-axis, the result is derived from the convex ordering of the involved probability distributions. Analogous results for non-centered operators are also considered.  相似文献   
44.
Two two-function minimax theorems are proved.The concavity-convexity conditions of the twofunctions involve strictly monotone transformations and mixing of the values of the two functions,and aredescribed by the inequalities as upward and weakly downward conditions.  相似文献   
45.
We construct models for the level by level equivalence between strong compactness and supercompactness in which for κ the least supercompact cardinal and δκ any cardinal which is either a strong cardinal or a measurable limit of strong cardinals, 2δ > δ + and δ is < 2δ supercompact. In these models, the structure of the class of supercompact cardinals can be arbitrary, and the size of the power set of κ can essentially be made as large as desired. This extends and generalizes [5, Theorem 2] and [4, Theorem 4]. We also sketch how our techniques can be used to establish a weak indestructibility result. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
46.
许心光  邵耀鹏等 《物理学报》2002,51(10):2266-2269
在KNSBN:Ce晶体中,利用二波耦合作用,在单一光束无法获得相位共轭光的条件下,实现了“猫”式互抽运相位共轭光输出,获得较高的共轭光发射率,实验结果表明,晶体的二波耦合作用可以使晶体的自抽运相位共轭光的阈值光强降低。入射光的入射角范围增大,响应时间缩短。  相似文献   
47.
The volume integral equation formalism is used to prove the scale invariance rule for an arbitrarily sized scatterer with an arbitrary shape, morphology, and orientation. The only assumptions are that the scatterer is made of optically isotropic linear materials and is embedded in a homogeneous, linear, isotropic, and nonabsorbing infinite medium.  相似文献   
48.
随着现代外语教学的发展,传统的俄语速读方法已远远不能满足要求。笔者认为,应适应时代的要求,充分利用现代化的教学手段和教学设备来提高速读课的效率。本文将阐述计算机辅助俄语速读课教学系统及其功能、特点,并论证该系统在学生形成良好的阅读习惯和提高阅读能力中的优势。  相似文献   
49.
《Electroanalysis》2006,18(24):2451-2457
This paper describes a layer‐by‐layer (LBL) self‐assembly process of chitosan (CTS) and gold nanoparticles (Au) on the pretreated negatively charged glassy carbon (GC) electrode to fabricate electrochemistry immunosensor with a nontoxic biomimetic interface, which provided an environment similar to a native system and allowed more freedom in orientation for immobilization of carcinoembryonic antibody (anti‐CEA) to monitor carcinoembryonic antigen (CEA). UV‐vis spectroscope, atomic force microscopy (AFM), and cyclic voltammetric (CV) measurements were used to follow the multilayer film formation. The performance of the biominetic interface and factors influencing the assay system were investigated in detail. The differential pulse voltammetry (DPV) current response is used for the CEA concentration assay. The dynamic range was from 0.50 to 80.00 ng mL?1 with a detection limit of 0.27 ng mL?1 at 3σ. In addition, the experiment results indicate that immobilization described in this proposed method exhibits a good sensitivity, selectivity, and stability.  相似文献   
50.
Paul阱中共面两离子系统的能量本征态   总被引:3,自引:0,他引:3       下载免费PDF全文
邬云文  海文华 《物理学报》2006,55(7):3315-3321
通过对Paul阱中共面两离子体系的研究,考虑共面两离子在Paul阱中库仑关联,得到了两离子系统Schrdinger方程的精确解;椐方程的精确解,分析了质心能级简并情况,计算了两离子的平衡距离和低能级的几个态函数,设计程序作出了质心径向概率分布图. 关键词: Paul阱 两离子 共面 量子逻辑操作  相似文献   
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