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71.
In 11 patients with alcohol-induced hyperlipemia, of whom 6 showed a Zieve Syndrome increased phospholipids, triglycerides and total cholesterol were found in the red cells stromal. The gasliquid chromatographic analysis of the phospholipid fatty acids showed increased contents of saturated and monounsaturated fatty acids C 16-C 18 smaller contents of longchain highly unsaturated fatty acids. The changes in the fatty acid pattern mainly occurred in patients with Zieve Syndrome and could be important for the mechanism of the hemolytic anemia. Theses findings could be in connexion with vitamin E deficiency. 相似文献
72.
Changes in motivation related to age differences and their relationship to A. Maslow's (1943–1971) hierarchy of needs were investigated with 111 Ss 9–80 yrs old, divided into 5 age groups (children, adolescents, young adults, middle-aged adults, old adults). Using the Life Motivation Scale, Ss ranked statements representing Maslow's 5 needs on 11 life components. ANOVAs (Age?×?Sex) yielded significant developmental differences for 4 needs but gave only limited support to Maslow's theory as a developmental model. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Picker KM 《Drug development and industrial pharmacy》2004,30(4):413-425
The aim of the study was to analyze very differently deforming materials using 3D parameter plots and consequently to gain deeper insights into the densification and deformation process described with the 3D model in order to define an ideal tableting excipient. The excipients used were dicalcium phosphate dihydrate (DCPD), sodium chloride (NaCl), microcrystalline cellulose (MCC), xylitol, mannitol, alpha-lactose monohydrate, maltose, hydroxypropyl methylcellulose (HPMC), sodium carboxymethylcellulose (NaCMC), cellulose acetate (CAC), maize starch, potato starch, pregelatinized starch, and maltodextrine. All of the materials were tableted to graded maximum relative densities (rhorel, max) using an eccentric tableting machine. The data which resulted, namely force, displacement, and time, were analyzed by the application of 3D modeling. Different particle size fractions of DCPD, CAC, and MCC were analyzed in addition. Brittle deforming materials such as DCPD exhibited a completely different 3D parameter plot, with low time plasticity, d, and low pressure plasticity, e, and a strong decrease in omega values when densification increased, in contrast to the plastically deforming MCC, which had much higher d, e, and omega values. e and omega values changed only slightly when densification increased for MCC. NaCl showed less of a decrease in omega values than DCPD did, and the d and e values were between those of MCC and DCPD. The sugar alcohols, xylitol and mannitol, behaved in a similar fashion to sodium chloride. This is also valid for the crystalline sugars, alpha-lactose monohydrate, and maltose. However, the sugars are more brittle than the sugar alcohols. The cellulose derivatives, HPMC, NaCMC, and CAC, are as plastic as MCC, however, their elasticity depends on substitution indicated by lower (more elastic) or higher (less elastic) omega values. The native starches, maize starch and potato starch, are very elastic, and pregelatinized starch and maltodextrine are less elastic and exhibited higher omega values. Deformation behavior as shown in 3D parameter plots depends on particle size for polymers such as CAC and MCC; however, it does not depend on particle size for brittle materials such as DCPD. An ideally deforming tableting excipient should exhibit high e, d, and omega values with a constant ratio of e and omega at increasing densification. 相似文献
74.
Here the interaction between a laminar two-phase, non-pre-mixed counterflow flame and a vortex is examined. Special emphasis is given to the influence of different flame and vortex parameters on the extinction behavior of the flame. Simultaneous planar laser-induced fluorescence of the CH radical layer produced by the flame and particle-image velocimetry measurements of the flowfield are used to characterize the flame-vortex interaction. These simultaneous diagnostics are used for the first time in this configuration. The extinction processes occurring during the flame-vortex interaction can be analyzed by this method, especially the influence of strain at the flame surface. The influence of the droplets on the extinction behavior appears clearly compared with a fully gaseous flame. The spray flame is weaker and extinguishes earlier than does a gaseous flame. In the measurements an additional broadband signal in the vicinity of the CH layer is probably due to the induced fluorescence of polycyclic aromatic hydrocarbons, excited at the same wavelength. 相似文献
75.
Katharina Nekolla Sabine Sellner Marc Praetner Karina Mildner Dagmar Zeuschner Fritz Krombach 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(14):1882-1890
So‐called membrane nanotubes are cellular protrusions between cells whose functions include cell communication, environmental sampling, and protein transfer. It has been previously reported that systemically administered carboxyl‐modified quantum dots (cQDs) are rapidly taken up by perivascular macrophages in skeletal muscle of healthy mice. Expanding these studies, it is found, by means of in vivo fluorescence microscopy on the mouse cremaster muscle, rapid uptake of cQDs not only by perivascular macrophages but also by tissue‐resident cells, which are localized more than 100 μm distant from the closest vessel. Confocal microscopy on muscle tissue, immunostained for the membrane dye DiI, reveals the presence of continuous membranous structures between MHC‐II‐positive, F4/80‐positive cells. These structures contain microtubules, components of the cytoskeleton, which clearly colocalize with cQDs. The cQDs are exclusively found inside endosomal vesicles. Most importantly, by using in vivo fluorescence microscopy, this study detected fast (0.8 μm s?1, mean velocity), bidirectional movement of cQDs in such structures, indicating transport of cQD‐containing vesicles along microtubule tracks by the action of molecular motors. The findings are the first to demonstrate membrane nanotube function in vivo and they suggest a previously unknown route for the distribution of nanomaterials in tissue. 相似文献
76.
77.
Ronald M. Meixner Dominik Cibis Klaus Krueger Holger Goebel 《Microsystem Technologies》2008,14(8):1137-1142
This paper presents a detailed study on the properties of different polymer inks based on poly(3,4ethylenedioxythiophene)/polystyrenesulfonate
regarding their processability in an experimental piezo driven drop-on-demand (DoD) micro-feeding system. Based on the rheological
properties of the used inks and the mechanical properties of the printing system characteristic values are derived which allow
to predict the processability of polymer inks in a given printing system. Beside the printability the influence of different
polymer inks on the electrical characteristics of printed organic field effect transistors is investigated. 相似文献
78.
Possible Approaches to the Prediction of Residence Time Distributions Although the experimental determination of residence time distributions is based on a black-box method, the signal shape also permits certain conclusions to be drawn about the internal conditions. However, if it is to provide a sole basis for elucidating process steps in a plant this method is soon overtaxed. A deeper theoretical penetration of the pertinent transport processes opens up the way ahead. However, since residence time distributions are based on mass-oriented considerations, substantial advances in fluid mechanics, where location-based considerations predominate, have not led to improved predictive capability. Yet the computer power now available offers a variety of ways of calculating residence-time distributions for a known flow profile, thus permitting a step in the direction of better predictability of residence time distributions. This article presents utilisable methods and evaluates them with regard to their demands on time and effort and their predictive power. Problems arising in connection with the models are discussed. 相似文献
79.
Since emulsions tend to become unstable with increasing temperature, reactions in emulsions are usually not performed at high temperatures. We show that non-aqueous inverse miniemulsions are relatively stable at temperatures higher than 150 °C. As an example of this remarkable stability, composite particles consisting of Ag nanoparticles and a polymer were synthesized via the polyol process in the monomer droplets to reduce silver ions to silver followed by the polymerization of the monomer. Silver nanoparticles were hence embedded in polyvinylpyrrolidone matrix particles. We showed here that non-aqueous miniemulsion nanodroplets are suitable loci for reactions performed at high temperature. 相似文献
80.
Thomas Finke Dominic Lingenfelser Katharina Bindler Ulrich Eisele Henning Bockhorn Gunther Brunklaus 《Journal of the American Ceramic Society》2009,92(8):1823-1830
This paper deals with the specific interaction of the dispersant 3,6,9-trioxadecanoic acid (TODA) with nano-ZrO2 surfaces. Special interest was directed towards degradation behavior of the adsorbates and its influence on dispersant capabilities of TODA regarding stabilization of ethanolic nano-ZrO2 suspensions. ZrO2 adsorption sites and the adsorbates formed are examined by diffuse reflectance infrared Fourier transform spectroscopy, thermal analysis, 1 H-, and 13 C-cross polarization magic angle spinning solid-state nuclear magnetic resonance spectroscopy. 1 H as well as 13 C-chemical shifts and the configurations of the corresponding adsorbed TODA species on zirconia sites are predicted by means of density functional theory quantum chemical calculations for supporting the interpretation of the experimental spectral data obtained. This work shows that combination of analytical and theoretical methods is an effective approach characterizing surface chemical properties of ceramic materials, determining sorption properties of organic process additives, investigating correspondent elementary and degradation reactions as well as clarifying cause-effect relationships in ceramic processes. 相似文献