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641.
Álvaro M. Lima Miguel A. Cerqueira Bartolomeu W.S. Souza Ed Carlos M. Santos José A. Teixeira Renato A. Moreira António A. Vicente 《Journal of food engineering》2010
The objective of this work was to produce new edible coatings, based on a mixture of galactomannans from novel sources (seeds of Adenanthera pavonina and Caesalpinia pulcherrima), collagen and glycerol, and to determine their influence in gas transfer rates when they are applied on mangoes and apples. The first part of the work consisted in obtaining coating solutions with the convenient values of wettability for each fruit; such coating solutions were then characterized in terms of their permeability (to CO2, O2 and water vapour), mechanical properties, colour and opacity. Gas transfer rates from mangoes coated with a solution of A. pavonina galactomannan (0.5%), collagen (1.5%) and glycerol (1.5%) were compared with those of mangoes without coating: 28% less O2 consumption and 11% less CO2 production were observed in coated mangoes. The same procedure was performed in apples (in this case using C. pulcherrima galactomannan (0.5%), collagen (1.5%) and no glycerol); the CO2 production and the O2 consumption was approximately 50% lower in apples with coating than in apples without coating. The results suggest that these coatings can reduce gas transfer rates in these fruits, and can be therefore important tools to extend their shelf life. 相似文献
642.
Ohne Zusammenfassung 相似文献
643.
Ed. Günzel 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1909,18(3):206-211
Ohne ZusammenfassungMitteilung aus dem Chemischen Laboratorium der Königlichen Auslandsfleischbeschaustelle zu Stettin. 相似文献
644.
645.
Performance is a critical issue in current massively parallel processors. However, delivery of adequate performance is not automatic and performance evaluation tools are required in order to help the programmer to understand the behaviour of a parallel program. In recent years, a wide variety of tools have been developed for this purpose, including tools for monitoring and evaluating performance and viaualization tools. However, these tools do not provide an abstract representation of performance. Massively parallel processors can generate a huge amount of performance data, and sophisticated methods for representing and displaying these data (e.g. visual and aural) are required. Performance views are not scalable in general and do not represent an abstraction of the performance data. The do-loop-surface display is proposed as an abstract representation of the performance of a particular do-loop in a program. It has been used to improve the performance of a matrix multiply parallel algorithm as well as to understand the behaviour of the following applications: matrix transposition (TRANS1) and fast fourier transform (FFT1) from the Genesis benchmarks, and the kernel of a fluid dynamics package (FIRE). These experiments were performed on a CM-5, a Meiko CS-1 and a PARSYS Supernode. The examples demonstrate that the do-loop-surface display is a useful way to represent performance. It is implemented using AVS (application visualization system), a standard data visualization package. 相似文献
646.
Virtual Reality - For most, an improvement in memory would always be desirable, whether from the point of view of an aging individual with declining memory, or from the perspective of someone... 相似文献
647.
Sharafat Ali Adam Ellison Jian Luo Mattias Edén 《Journal of the American Ceramic Society》2023,106(3):1748-1765
We explore the formation and composition–structure–property correlations of transparent Ca–Al–Si–O–N glasses, which were prepared by a standard melt-quenching technique using AlN as the nitrogen source and incorporating up to 8 at.% of N. Their measured physical properties of density, molar volume, compactness, refractive index, and hardness—along with the Young, shear, and bulk elastic moduli—depended roughly linearly on the N content. These effects are attributed primarily to the improved glass-network cross-linking from N compared to O, rather than the formation of higher-coordination AlO5 and AlO6 groups, where 27Al magic-angle-spinning nuclear magnetic resonance experimentation revealed that aluminum is predominately present in tetrahedral coordination as AlO4 units. Yet, several physical properties, such as the refractive index along with the bulk, shear, and Young's elastic moduli, increase concomitantly with the Al content of the glass. We discuss the incompletely understood mechanical–property boosting role of Al as observed both herein and in previous reports on oxynitride glasses, moreover suggesting glass-composition domains that are likely to offer optimal mechanical properties. 相似文献
648.
Peng Lv Zhao Sun Fugang Wang Yang Yu Fan Yang Shengjun Yue Mattias Edén Liang Chen Tieshan Wang 《Journal of the American Ceramic Society》2023,106(10):5766-5780
We examine the impact of the glass network-modifier cation field strength (CFS) on ion irradiation-induced mechanical property changes in borosilicate (BS) glasses for the ternary M2O–B2O3–SiO2 systems with M = {Na, K, Rb} and the quaternary [0.5M(2)O–0.5Na2O]–B2O3–SiO2 systems with M = {Li, Na, K, Rb Mg, Ca, Sr, Ba}. 11B nuclear magnetic resonance (NMR) experiments on the as-prepared BS glasses yielded the fractional population of four-coordinated B species (B[4]) out of all {B[3], B[4]} groups in the glass network, along with the fraction of B[4]–O–Si linkages out of all B[4]–O–Si/B bonds. Both parameters correlated linearly with the (average) CFS of the M+ and/or {M(2)+, Na+} cations. Both the nanoindentation-derived hardness and Young's modulus values of the glasses reduced upon their irradiation by Si2+ ions, with the property deterioration decreasing linearly with increasing Mz+ CFS, that is, for higher Mz+⋅⋅⋅O interaction strength. The irradiation damage of the glass network also increased linearly with the fraction of B[4]–O–Si linkages, which are the second weakest in the structure after the Mz+⋅⋅⋅O bonds. Our results underscore the advantages of employing BS glasses with high-CFS cations for enhancing the radiation resistance for nuclear waste storage. 相似文献
649.
Joseph R. Hyatt Siyu Zhang Casimir C. Akoh 《Journal of the American Oil Chemists' Society》2023,100(12):945-959
Oleogels and emulgels were developed with winterized algal oil from Schizochytrium spp. rich in ω-3 fatty acids (FAs) to overcome physical limitations of using a highly unsaturated lipid source in food applications. Both gel types were developed using monolaurin or a combination of mono- and diacylglycerols (MAG/DAG) as the gelator at concentrations of 8%, 10%, or 12% (w/w) in oil or emulsion. A 30-day oxidation study was conducted using peroxide value, p-Anisidine value, and change in FA composition to measure the level of oxidation. Oleogel and emulgel samples exhibited a higher oxidative stability than bulk algal oil and oil-in-water emulsion as control groups, respectively. The 12% monolaurin oleogel outperformed others in oxidative stability, preventing oxidation of approximately 11.66% and 7.86% of EPA and DHA, respectively, compared to algal oil. Physical characteristics including thermal behavior, solid fat content (SFC), rheology, morphology, and polymorphism were studied. Results indicated that MAG/DAG oleogels and monolaurin emulgels were the most physically stable. The SFC of 12% MAG/DAG oleogel at 30°C was 10.27% whereas 12% monolaurin oleogel was only 4.51%. Both gel types developed with monolaurin and MAG/DAG could be used for different applications as they exhibited desirable qualities such as oxidative stability and improved physical characteristics. 相似文献