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1.
In this paper the response of nonlinear systems driven by parametric Poissonian white noise is examined.As is well known, the response sample function or the response statistics of a system driven by external white noise processes is completely defined. Starting from the system driven by external white noise processes, when an invertible nonlinear transformation is applied, the transformed system in the new state variable is driven by a parametric type excitation. So this latter artificial system may be used as a tool to find out the proper solution to solve systems driven by parametric white noises. In fact, solving this new system, being the nonlinear transformation invertible, we must pass from the solution of the artificial system (driven by parametric noise) to that of the original one (driven by external noise, that is known). Moreover, introducing this invertible nonlinear transformation into the Itô’s rule for the original system driven by external input, one can derive the Itô’s rule for systems driven by a parametric type excitation, directly. In this latter case one can see how natural is the presence of the Wong–Zakai correction term or the presence of the hierarchy of correction terms in the case of normal and Poissonian white noise, respectively. Direct transformation on the Fokker–Planck and on the Kolmogorov–Feller equation for the case of parametric input are found. 相似文献
2.
Magorzata Zubielewicz Elbieta Kamiska-Tarnawska Antonina Kozowska 《Progress in Organic Coatings》2005,53(4):276-285
Investigations have been carried out on properties of coatings, differing by their pigmentation and binder, and applied on different chemical pre-treatments of the steel surface. Paints based on alkyd and alkyd-melamine binders, pigmented with zinc phosphate and modified basic zinc phosphate were applied on amorphous and crystalline phosphated steel surface and, for the comparison purpose, on degreased steel surface. The effect of the binder, the pigment and the pre-treatment of the steel surface on the protective properties of the coatings were determined by measurements of adhesion, water absorption and water permeability and by results obtained in salt spray and Prohesion tests. Coatings based on alkyd binder show a lower damage degree and good retention of adhesion in corrosion conditions, in spite of a higher water absorption and water permeability and a lower initial adhesive strength. Protective properties of coatings have been found to be highly dependent upon the substrate pre-treatment. Chemical pre-treatment of the steel substrate increases the protective properties of the system, which is particularly evident in the case of crystalline phosphating and the coating pigmented with modified basic zinc phosphate. This phenomenon can be explained by the synergism between this phosphate pigment with crystalline phosphate layer. 相似文献
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This paper presents the design of an open photoacoustic Helmholtz cell in which high acoustic volumes with quarter-wave ducts act as high-impedance separators between the main Helmholtz cell structure and the exterior. As a result, penetration of the external acoustic noise into the cell was substantially reduced in comparison to earlier open Helmholtz cell designs. Although the presented cell is not windowless, the photoacoustic background signal resulting from the absorption of the light by the windows is significantly lower in comparison to standard Helmholtz cells. Such an effect was obtained by locating the windows not at the relatively small sample cavity, but at the acoustic buffers, for which the volumes are two orders of magnitude higher. The proposed cell is dedicated for gas or liquid measurements, and its design allows for constant flow of the fluid. Hence, it can be used in continuous, real-time photoacoustic measurements. 相似文献
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Dmitrii Iudin Marina Vasilieva Elena Knyazeva Viktor Korzhikov-Vlakh Elena Demyanova Antonina Lavrentieva Yury Skorik Evgenia Korzhikova-Vlakh 《International journal of molecular sciences》2022,23(5)
The growing number of drug-resistant pathogenic bacteria poses a global threat to human health. For this reason, the search for ways to enhance the antibacterial activity of existing antibiotics is now an urgent medical task. The aim of this study was to develop novel delivery systems for polymyxins to improve their antimicrobial properties against various infections. For this, hybrid core–shell nanoparticles, consisting of silver core and a poly(glutamic acid) shell capable of polymyxin binding, were developed and carefully investigated. Characterization of the hybrid nanoparticles revealed a hydrodynamic diameter of approximately 100 nm and a negative electrokinetic potential. The nanoparticles demonstrated a lack of cytotoxicity, a low uptake by macrophages, and their own antimicrobial activity. Drug loading and loading efficacy were determined for both polymyxin B and E, and the maximal loaded value with an appropriate size of the delivery systems was 450 µg/mg of nanoparticles. Composite materials based on agarose hydrogel were prepared, containing both the loaded hybrid systems and free antibiotics. The features of polymyxin release from the hybrid nanoparticles and the composite materials were studied, and the mechanisms of release were analyzed using different theoretical models. The antibacterial activity against Pseudomonas aeruginosa was evaluated for both the polymyxin hybrid and the composite delivery systems. All tested samples inhibited bacterial growth. The minimal inhibitory concentrations of the polymyxin B hybrid delivery system demonstrated a synergistic effect when compared with either the antibiotic or the silver nanoparticles alone. 相似文献
7.
This paper argues that energy efficiency and conservation is a noncontroversial, critical, and equitable option for rich and
poor alike. Although there is growing scientific and political consensus on its significance as an important option at global
and national level, the political momentum for taking action is not commensurate with the potential in the sector or the urgency
with which measures need to be taken to deal with climate change. The current global energy (efficiency) governance framework
is diffuse. This paper submits that there are four substantive reasons why global governance should play a complementary role
in promoting energy efficiency worldwide. Furthermore, given that market mechanisms are unable to rapidly mobilize energy
efficiency projects and that there are no clear vested interests in this field which involves a large number of actors, there
is need for a dedicated agency to promote energy efficiency and conservation. This paper provides an overview of energy efficiency
options presented by IPCC, the current energy efficiency governance structure at global level, and efforts taken at supranational
and national levels, and makes suggestions for a governance framework. 相似文献
8.
Fabrice Burel Hassan Oulyadi Claude Bunel Vladimir Grishchenko Natalya Busko Antonina Barantsova Vitaly Boiko 《Journal of Polymer Research》2011,18(6):2265-2273
Azo-bis(isobutyroamidoxime) was synthesized and used as functionalized initiator to prepare a liquid isoprene bearing amidoxime
end groups via radical polymerization. The polymer was characterized by FT-IR, Gel Permeation Chromatography and NMR. In particular,
the structure of the polymer was investigated using 1D and 2D NMR techniques. The distribution of the different isoprene units
(1,4-trans, 1,4-cis, 1,2 and 3,4), as well as the structure of the amidoxime end-groups was determined. It was found that
the structure of the end groups was governed by the steric hindrance of the initiator. Only 1,4 and 4,1 functionalized end
units were evidenced, with a majority of 4,1 end units. 相似文献
9.
V. A. Sukhnev L. A. Zhukova A. É. Ioffe N. A. Kolokolova 《Measurement Techniques》1963,6(12):1003-1005
Conclusions The above model of a double-liquid micromanometer has been in use for the past six months. During this period no noticeable changes in the physicochemical properties of the liquid have been observed. The dividing line remained clearly visible. Vacuum sealing was not disturbed by displacing the instrument. The manometer legs were separated only during measurements. It was, therefore, possible to avoid sharp variations of pressure differences in the measuring legs of the micromanometers. Formation of emulsions was not observed under normal operating conditions of the instrument. 相似文献
10.