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91.
Cover Feature: Mannose‐Decorated Multicomponent Supramolecular Polymers Trigger Effective Uptake into Antigen‐Presenting Cells (ChemBioChem 9/2018)
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In this paper, we present a flexible and efficient approach for the integration of order‐independent transparency into a deferred shading pipeline. The intermediate buffers for storing fragments to be shaded are extended with a dynamic and memory‐efficient storage for transparent fragments. The transparency of an object is not fixed and remains programmable until fragment processing, which allows for the implementation of advanced materials effects, interaction techniques or adaptive fade‐outs. Traversing costs for shading the transparent fragments are greatly reduced by introducing a tile‐based light‐culling pass. During deferred shading, opaque and transparent fragments are shaded and composited in front‐to‐back order using the retrieved lighting information and a physically‐based shading model. In addition, we discuss various configurations of the system and further enhancements. Our results show that the system performs at interactive frame rates even for complex scenarios. 相似文献
94.
Pawel Ziolkowski Christian Stiewe Johannes de Boor Ines Druschke Knud Zabrocki Frank Edler Sebastian Haupt Jan König Eckhard Mueller 《Journal of Electronic Materials》2017,46(1):51-63
Thermoelectric generators (TEGs) convert heat to electrical energy by means of the Seebeck effect. The Seebeck coefficient is a central thermoelectric material property, measuring the magnitude of the thermovoltage generated in response to a temperature difference across a thermoelectric material. Precise determination of the Seebeck coefficient provides the basis for reliable performance assessment in materials development in the field of thermoelectrics. For several reasons, measurement uncertainties of up to 14% can often be observed in interlaboratory comparisons of temperature-dependent Seebeck coefficient or in error analyses on currently employed instruments. This is still too high for an industrial benchmark and insufficient for many scientific investigations and technological developments. The TESt (thermoelectric standardization) project was launched in 2011, funded by the German Federal Ministry of Education and Research (BMBF), to reduce measurement uncertainties, engineer traceable and precise thermoelectric measurement techniques for materials and TEGs, and develop reference materials (RMs) for temperature-dependent determination of the Seebeck coefficient. We report herein the successful development and qualification of cobalt-doped β-iron disilicide (β-Fe0.95Co0.05Si2) as a RM for high-temperature thermoelectric metrology. A brief survey on technological processes for manufacturing and machining of samples is presented. Focus is placed on metrological qualification of the iron disilicide, results of an international round-robin test, and final certification as a reference material in accordance with ISO-Guide 35 and the “Guide to the expression of uncertainty in measurement” by the Physikalisch-Technische Bundesanstalt, the national metrology institute of Germany. 相似文献
95.
Supercritical carbon dioxide dyeing of cotton modified with the fibre reactive group 2,4,6-trichloro-1,3,5-triazine has been examined and the results are discussed. The modification of cotton was carried out in acetone, as well as by a new method using water as the solvent. For level dyeing results a degree of fixation of the fibre reactive group on cotton of 3% owf was required without changing the hydrophilicity of the fibre. The results show that dyeing of modified cotton is possible with dyes containing hydroxy or amino groups which react via a substitution reaction with the chlorine atoms of 4,6-dichloro-1,3,5-triazine-2-yl on the fibre surface. The K/S values at 383 nm of modified cotton dyed with CI Disperse Yellow 23 were found to be between 1.44 and 4.79 depending on the dyeing conditions used. The washing, rubbing and light fastness data that were obtained were between 3 and 5. 相似文献
96.
The effect of dyeing in supercritical fluids on characteristics of the polymeric structure is investigated using poly(ethylene terephthalate) fibers. The supercritical fluid (CO2) causes a decrease in the glass transition temperature and the formation of a network of stabilizing crystallites, which — without the use of a fluid — can only be obtained at significantly higher temperatures. The implications of fiber structure for successful dyeing or impregnation of fibrous material in supercritical systems are discussed. 相似文献
97.
Anatoly Goifman Jenny Gun Faina Gelman Irina Ekeltchik Eckhard Worch Ovadia Lev 《Israel journal of chemistry》2006,46(1):17-26
The catalytic performance of pyrolyzed carbon-supported cobalt-nitrogen donor (CoN4) catalysts for the oxidation of thiol compounds by dioxygen in aqueous solution was studied. This paper continues our previous line of research, which was inspired by the electrocatalytic reduction of oxygen on pyrolyzed carbon-supported cobalt-porphyrins and related tetra-coordinated nitrogen donor-transition metal complexes (MeN4, where Me stands for a transition metal atom). Both pyrolyzed carbon-supported Co-imidazole and Co-porphyrin exhibited fast catalytic oxidation of the different thiols. The rate of oxidation of different thiols on the pyrolyzed CoN4 catalysts was compared to the homogeneous rate of oxidation using 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin Co(II) tetrasodium salt as catalyst. Based on the cobalt content, the heterogeneous catalysts always outperformed the homogeneous one, and at times even exhibited 4,100-fold better catalysis. The dependence of the catalytic rate of oxidation on the preparation temperature was investigated, showing an optimal catalysis at ˜650 °C for the cobalt-imidazole catalyst. The decrease in catalytic performance after heat treatment at elevated temperature was attributed to the formation of cobalt metal acting as a generator of carbon nanotubes. 相似文献
98.
Jakob Schulz Arkadij Stalevitsch Achim Eickmeier Adelgund Bossmann Eckhard Schollmeyer 《大分子材料与工程》1996,234(1):159-175
The evaluation of the viscoelastic response of synthetic fibres from stress-relaxation data over a wide range of time at different strain rates is very time-consuming. Therefore, mathematical models are used to describe the viscoelastic response. The characteristic of synthetic fibres is that already at very low deformation rates like an elongation < 1% a nonlinear viscoelasticity has to be considered. Based on the analytical representation of isothermal viscoelastic behaviour by Boltzmann a new model making an assertion to the nonlinear viscoelasticity is proposed. Applying this model, the calculated values of moduli and relaxation tensions of the fibres Nomex® and PEEK are in good agreement with the experimental values. 相似文献
99.
Marco Wendler Michael Hauser Eckhard Frank Sandig Olena Volkova 《Metallurgical and Materials Transactions B》2018,49(2):581-589
The influence of chemical composition, temperature, and pressure on the nitrogen solubility of various high alloy stainless steel grades, namely Fe-14Cr-(0.17-7.77)Mn-6Ni-0.5Si-0.03C [wt pct], Fe-15Cr-3Mn-4Ni-0.5Si-0.1C [wt pct], and Fe-19Cr-3Mn-4Ni-0.5Si-0.15C [wt pct], was studied in the melt. The temperature-dependent N-solubility was determined using an empirical approach proposed by Wada and Pehlke. The thus calculated N-concentrations overestimate the actual N-solubility of all the studied Fe-Cr-Mn-Ni-Si-C steel melts at a given temperature and pressure. Consequently, the calculation model has to be modified by Si and C because both elements are not recognized in the original equation. The addition of the 1st and 2nd order interaction parameters for Si and C to the model by Wada and Pehlke allows a precise estimation of the temperature-dependent nitrogen solubility in the liquid steel bath, and fits very well with the measured nitrogen concentrations during processing of the steels. Moreover, the N-solubility enhancing effect of Cr- and Mn-additions has been demonstrated. 相似文献
100.
Kilian Simmet Eckhard Wolf Valeri Zakhartchenko 《International journal of molecular sciences》2021,22(1)
The nucleus of a differentiated cell can be reprogrammed to a totipotent state by exposure to the cytoplasm of an enucleated oocyte, and the reconstructed nuclear transfer embryo can give rise to an entire organism. Somatic cell nuclear transfer (SCNT) has important implications in animal biotechnology and provides a unique model for studying epigenetic barriers to successful nuclear reprogramming and for testing novel concepts to overcome them. While initial strategies aimed at modulating the global DNA methylation level and states of various histone protein modifications, recent studies use evidence-based approaches to influence specific epigenetic mechanisms in a targeted manner. In this review, we describe—based on the growing number of reports published during recent decades—in detail where, when, and how manipulations of the epigenome of donor cells and reconstructed SCNT embryos can be performed to optimize the process of molecular reprogramming and the outcome of nuclear transfer cloning. 相似文献