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971.
Claudia F. Galinha Gilda Carvalho Carla A. M. Portugal Giuseppe Guglielmi Maria A. M. Reis João G. Crespo 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(7):985-992
BACKGROUND: The use of two‐dimensional (2D) fluorescence for monitoring complex biological systems requires careful assessment of the effect of chemical species present, which may be fluorescent and/or may interfere with the fluorescence response of target fluorophores. Given the complexity of fluorescence data (excitation emission matrices—EEMs), the challenge is how to recover the information embedded into those EEMs that can be related quantitatively with the observed performance of the biological processes under study. RESULTS: This work shows clearly that interference effects (such as quenching and inner filter effects) occur due to the presence of multiple species in complex biological media, such as natural water matrices, wastewaters and activated sludge. A statistical multivariate analysis is proposed to recover quantitative information from 2D fluorescence data, correlating EEMs with the observed performance. A selected case study is discussed, where 2D fluorescence spectra obtained from the effluent of a membrane bioreactor were compressed using PARAFAC and successfully correlated with the effluent chemical oxygen demand, using projection to latent structures modelling. CONCLUSION: This study demonstrates the potential of using 2D fluorescence spectroscopy as a status fingerprint. Additionally, it is shown how statistical multivariate data analysis can be used to correlate EEMs with selected performance parameters for monitoring of biological systems. Copyright © 2011 Society of Chemical Industry 相似文献
972.
Konstantinos Iliopoulos George Chatzikyriakos Maria DemetriouTheodora Krasia-Christoforou Stelios Couris 《Optical Materials》2011,33(8):1342-1349
The synthesis and characterization of novel micellar nanohybrids with controllable sizes consisting of palladium nanosized core and covered by well-defined poly(lauryl methacrylate)-block-poly(2-(acetoacetoxy)ethyl methacrylate) (pLauMA-b-pAEMA) diblock copolymers are reported. Their nonlinear optical (NLO) response (i.e. nonlinear refraction and absorption and the third-order susceptibility χ(3)) is also studied under 35 ps laser excitation both in the visible and in the infrared and found to be insensitive to the size of the micelles while it was found to be greatly affected by the molar fraction of the AEMA block. To the best of our knowledge it is the first time that such Pd micellar nanohybrids are synthesized and investigated towards their NLO properties. The magnitude of the nonlinear optical response of these nanohybrids renders them promising candidates for potential optoelectronic applications. 相似文献
973.
Maria Ferreira Fernanda A. R. Oliveira &Rolf Jost 《International Journal of Food Science & Technology》1999,34(1):27-32
Summary An attempt was made to reduce the microbial load of unpasteurized fresh egg white by using cross-flow microfiltration and a Tetra-Laval bactocatch installation. Cross-flow tangential microfiltration of liquid fresh egg white was not feasible as there was irreversible membrane clogging within a few minutes of operation. As membrane clogging could have been caused by ovomucin, this protein was removed from whole fresh egg white by increasing the salt strength and lowering the pH. Ovomucin-depleted egg white (ODEW) was successfully microfiltered on the same membrane. Compared to fresh egg white, ODEW had lower foaming and viscous properties, and these properties remained unchanged after bactofiltration. The reduction of microbial load was, however, relatively low. 相似文献
974.
Kristofer Fredin Erik M.J. Johansson Tobias Blom Maria Hedlund Stefan Plogmaker Hans Siegbahn Klaus Leifer Håkan Rensmo 《Synthetic Metals》2009,159(1-2):166-170
We describe a method to fill thin films of nanoporous TiO2 with solid organic hole-conducting materials and demonstrate the procedure specifically for use in the preparation of dye-sensitized solar cells. Cross-sections of the films were investigated by scanning electron microscopy and it was observed that a hot molten organic material fills pores that are 10 μm below the surface of the film. We characterized the incident photon to current conversion efficiency properties of the solid TiO2/organic dye/organic hole-conductor heterojunctions and the spectra show that the dye is still active after the melting process. 相似文献
975.
Intermetallic compounds of Al3Ti and L12 (Al3Ti base) microalloyed with Fe have been obtained using a melting/casting rapid solidification technique. Microstructural characterization of these alloys has been carried out through analytical SEM observations and also x-ray diffraction studies. Contaminants in these alloys have also been studied and their nature explored. Other morphology structural features such as grain size have been studied. 相似文献
976.
Erica Bazzan Mariaenrica Tin Alvise Casara Davide Biondini Umberto Semenzato Elisabetta Cocconcelli Elisabetta Balestro Marco Damin Claudia Maria Radu Graziella Turato Simonetta Baraldo Paolo Simioni Paolo Spagnolo Marina Saetta Manuel G. Cosio 《International journal of molecular sciences》2021,22(12)
Extracellular vesicles (EVs) are a family of particles/vesicles present in blood and body fluids, composed of phospholipid bilayers that carry a variety of molecules that can mediate cell communication, modulating crucial cell processes such as homeostasis, induction/dampening of inflammation, and promotion of repair. Their existence, initially suspected in 1946 and confirmed in 1967, spurred a sharp increase in the number of scientific publications. Paradoxically, the increasing interest for EV content and function progressively reduced the relevance for a precise nomenclature in classifying EVs, therefore leading to a confusing scientific production. The aim of this review was to analyze the evolution of the progress in the knowledge and definition of EVs over the years, with an overview of the methodologies used for the identification of the vesicles, their cell of origin, and the detection of their cargo. The MISEV 2018 guidelines for the proper recognition nomenclature and ways to study EVs are summarized. The review finishes with a “more questions than answers” chapter, in which some of the problems we still face to fully understand the EV function and potential as a diagnostic and therapeutic tool are analyzed. 相似文献
977.
立面、周边环境以及对所在街区的一系列回应,是玛丽蒂姆酒店的设计要点。这个占地约1.2万m2的酒店基地紧邻文化中心(Kulturforum)和著名的文物保护建筑贝壳屋(Shellhaus,建筑师:Emil Fahrenkamp),且距国家美术馆和波茨坦广场不远。 相似文献
978.
This work studies how drainage of a wet foam is affected by certain characteristics of its container: diameter, wettability and shape of the walls. Drainage is registered by three simultaneous techniques: (a) electrical conductance measurements for the evolution of the local liquid fraction, (b) close-up photos for the evolution of the local bubble size distribution and (c) volumetric measurements for the evolution of the global liquid fraction in the entire container. Electrical measurements are conducted at different heights along the foam with the aid of several pairs of non-intrusive ring electrodes. Three cylindrical Plexiglas containers of different diameter are used, before and after treatment of their walls to allow tests with hydrophobic and hydrophilic walls, respectively. To resemble the shape of common industrial containers, the lower part of the largest container has a gradually reducing diameter towards its bottom. Foam decay is slower in the hydrophobic containers, this being less evident as diameter increases. Moreover, the role of diameter and shape is complex since the highest drainage rate is measured at the largest container whereas the lowest one at the medium container. The possible effect of the container walls in promoting the macroscopic rigidity of the foam structure is discussed 相似文献
979.
We examined whether personality judgments were present in texts of the diverse religious and philosophical traditions that emerged during the Great Transformation, an era spanning roughly 1000 BCE to 200 BCE. Some psychologists have suggested that the tendency of humans to judge personality has evolved; if some ancient societies failed to record personality judgments, it would be evidence against such an evolutionary position. In addition, learning about the prevalence and specifics of ancient personality judgments can help psychologists better understand the prehistory of personality psychology. Eight cultural traditions were studied: two each from China (Confucianism, Taoism), Greece (Classical and Hellenistic philosophy), India (Buddhism, Hinduism), and the Middle East (Judaism, Zoroastrianism). We found evidence that personality judgments were an important aspect of all of these traditions. Not only did people judge one another, but they also offered instructions on how to judge others. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献