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541.
A. D. Bruno 《Journal of Dynamical and Control Systems》1997,3(4):471-491
All local and asymptotic first approximations of a polynomial, a differential polynomial, and of a system of such polynomials
can be selected algorithmically. Here the first approximation of a solution to the system of equations is a solution to the
corresponding first approximation of the system of equations. The power transformations induce linear transformations of vector
exponents and commute with the operation of selecting first approximations. In the first approximation of a system of equations
they allow one to reduce the number of parameters and to reduce the presence of some variables to the form of derivatives
of their logarithms. If the first approximation is the linear system, then in many cases the system of equations can be transformed
into the normal form by means of the formal change of coordinates. The normal form is reduced to the problem of lower dimension
by means of the power transformation. Combining these algorithms, we can resolve a singularity in many problems, find parameters
determining the properties of solutions, and obtain the asymptotic expansions of solutions. Some applications from mechanics,
celestial mechanics, and hydrodynamics are indicated.
The work was partially supported by Russian Foundation for Basic Research, Grant 96-01-01411. 相似文献
542.
Jérôme DanguyAuthor Vitae Bruno van Pottelsberghe de la PotterieAuthor Vitae 《World Patent Information》2011,33(3):240-247
This paper puts forward a sustainable fee structure for the EU Patent (COMPAT). The proposal includes pre-grant and post-grant fees and illustrates the differences between Euro-direct applications and PCT applications. The break-even analysis shows that the COMPAT would make the European patent system more attractive with significantly lower relative costs. At the same time, the new schedule provides a financially sustainable model for the system by preserving relatively high absolute fees and allowing for a fee reduction for small innovative firms and public research organizations. 相似文献
543.
544.
Marta Fernanda ZotarelliBarbara Daniela Almeida Porciuncula João Borges Laurindo 《Journal of food engineering》2012,108(4):523-531
The aim of this work was to evaluate the application of a convective multi-flash drying process (CMFD) to producing dehydrated and crisp fruits. To accomplish this process, samples of banana (Musa sapientum L.) or mango (Mangifera indica L.) were heated to 60 °C by hot air, and a vacuum pulse was applied, which resulted in dehydration by a combination of convective drying and flash evaporation. Banana processed by CMFD had a moisture content of 0.293 g/g (dry basis) and aw = 0.272 after 3 h of processing. Mango had a moisture content of 0.09 g/g and aw = 0.359 after 4 h of processing. Puncture tests on fruits dehydrated by CMFD and on commercial freeze-dried fruits showed strain-force curves with many peaks (jagged curves). For CMFD much smaller global shrinkage was observed. These results indicate that the CMFD process can be applied for producing crispy fruits and is an alternative to the freeze-drying process. 相似文献
545.
陈林容 《四川轻化工学院学报》2010,(2):238-241,248
文章通过对四川盆地海相三叠纪蒸发岩硫同位素δ^34S组成特征的对比分析,针对该区域三叠系δ^34S具有异常高值并且呈现随时间由早到晚逐渐轻化的特点,结合其沉积地质背景、物化条件,特别是对复杂条件下同位素分馏、地质地球化学特征的研究,对硬石膏的δ^34S异常高值和随蒸发而逐渐贫化的地质成因进行了探讨,旨在为重建古环境及地层的划分和对比提供重要依据。研究表明,硬石膏中δ^34S异常高值的产生主要是处在封闭环境、硫酸盐细菌还原时的同位素分馏作用的结果。 相似文献
546.
采用水热合成法制备了CuO-ZnO/SAPO-34复合催化剂,以CuO-ZnO为甲醇合成催化剂,以SAPO-34分子筛为甲醇脱水催化剂,研究了催化二氧化碳加氢一步法制备低碳烯烃的方法。通过XRD、TEM、SEM、IR和固定床反应活性评价,系统地考察了复合催化剂的物化性质和催化反应性能。在反应温度270℃、压力3.5MPa、n(H2)∶n(CO2)=4∶1、体积空速为1 600h-1的反应条件下,该催化剂表现出较好的活性和选择性。CO2的转化率可达到18.71%,乙烯、丙烯的产率分别达到9.27%和4.76%。 相似文献
547.
Brenda Oppert R. Tracy Ellis Jonathan Babcock 《Journal of Stored Products Research》2010,46(3):143-148
Two crystalline protoxins from Bacillus thuringiensis (Bt), Cry1Fa1 and Cry34Ab1/Cry35Ab1 (Cry1F, Cry34/35Ab1), were evaluated for efficacy against lepidopteran and coleopteran storage pests. Cry1F was tested against the lepidopterans Sitotroga cerealella (Angoumois grain moth) and colonies of Plodia interpunctella (Indian mealmoth) that are susceptible or resistant to Bt Cry1Ab and Cry1Ac toxins, Bt subspecies entomocidus, and the commercial formulation Dipel®. Cry1F was also tested against the coleopterans Cryptolestes pusillus (flat grain beetle) and Tribolium castaneum (red flour beetle). Cry34/35Ab1 was tested against S. cerealella, C. pusillus, and T. castaneum, and against additional coleopteran storage pests, including Tenebrio molitor (yellow mealworm), Trogoderma variabile (warehouse beetle), Oryzaephilus surinamensis (sawtoothed grain beetle), Rhyzopertha dominica (lesser grain borer), and Sitophilus oryzae (rice weevil). Strains of Bt-susceptible or -resistant P. interpunctella generally were more sensitive to Cry1A protoxin or toxin than either Cry1F protoxin or Dipel. Despite difficulties with the bioassay of S. cerealella larvae, the data suggest that Cry1F and Cry34/35Ab1 caused increased larval mortality, and a developmental delay was observed and no pupae emerged with 0.9% Cry1F. Neither Cry1F nor the corn rootworm-active toxin Cry34/35Ab1 significantly affected the biological parameters of the coleopteran species evaluated. 相似文献
548.
549.
Sidra Nawaz Muhammad Sarfraz Asif Ali Qaiser Muneerah Alomar Soumaya Gouadria Amal Ali BaQais 《应用聚合物科学杂志》2024,141(8):e54971
Gas separation process is an effective method for capturing and removing CO2 from post-combustion flue gases. Due to their various essential properties such as ability to improve process efficiency, polymeric membranes are known to dominate the market. Trade-off between gas permeability and selectivity through membranes limits their separation performance. In this study, solution casting cum phase separation method was utilized to create polyethersulfone-based composite membranes doped with carbon nanotubes (CNTs) and silico aluminophosphate (SAPO-34) as nanofiller materials. Membrane properties were then examined by performing gas permeation test, chemical structural analysis and optical microscopy. While enhancing membranes CO2 permeance, SAPO-34 and CNTs mixture improved their CO2/N2 selectivity. By carefully adjusting membrane casting factors such as filler loadings. Using Taguchi statistical analysis, their carbon capture efficiency was improved. The improved mixed-matrix membrane with loading of 5 wt% CNTs and 10 wt% SAPO-34 in PES showed highly promising separation performance with a CO2 permeability of 319 Barrer and an ideal CO2/N2 selectivity of 12, both of which are within the 2008 Robeson upper bound. A better mixed-matrix membrane with outstanding CO2/N2 selectivity and CO2 permeability was produced as a result of the synergistic effect of adding two types of fillers in optimized loading. 相似文献
550.