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991.
This study reports on the results of repeated gavages and dietary feeding of lutein dispersed either in phospholipids or fatty
acid micelles or vegetable oils and the effects on lutein bioavailability and antioxidant enzymes in rats. For the gavage
study, rats (n = 5/group) were intubated with lutein solubilized either in oleic acid (OLA, 18:1n-9) or linoleic acid (LNA, 18:2n-6) or
phosphatidylcholine (PC) or lysophosphatidylcholine (LPC) or no phospholipid (NoPL) micelles for 10 days. For the dietary
study, rats (n = 5/group) were fed a diet containing fenugreek leaf (lutein source), either with olive (OO) or sunflower (SFO) or groundnut
(GNO, control) oil or l-α-lecithin (PL) for 4 weeks. The gavage study showed that the plasma, liver and eye lutein levels in OLA and LPC groups were
higher by 23.9, 20.8 and 25.5% and 16.1, 28.5 and 14.0% than LNA and PC groups, respectively. The dietary study showed the
plasma (35.0 and 43.5%) and eye (18.5 and 37.0%) lutein levels in OO were higher than SFO and GNO groups. The plasma and eye
lutein levels in the PL group were higher by 20 and 31.3% than in the control. It is evident that OO and PL modulate lutein
absorption, which in turn modulates antioxidant enzymes and fatty acids in plasma and tissues compared to SFO. Hence, selection
of the fat source may be vital to enhancing the lutein bioavailability. 相似文献
992.
Prakash Manish 《Chemical engineering science》2009,64(8):1798-1805
Quality of mixing in a modified downflow bubble column has been analyzed by using information entropy theory. Mass transfer efficiency based on quality of mixing has also been enunciated in this work. Empirical models have been developed for downflow system with the parameters which affect the quality of mixing and mass transfer efficiency. The developed correlation for quality of mixedness in the downflow bubble column was interpreted by the mass transfer phenomena. The present analysis on the quality of mixing in downward two-phase flow in bubble column may give insight into a further understanding and modeling of multiphase reactors in industrial applications. 相似文献
993.
Singh A.K. Prakash R. Dwivedi A.D.D. Chakrabarti P. 《Electron Device Letters, IEEE》2008,29(6):571-574
Polyanthranilic acid (PANA), a self-doped processible conducting polymer, was synthesized and used for the first time for fabrication of contacts with configurations of (Al, Ti, Sn metal)/PANA/indium tin oxide-coated glass. The current-voltage (I-V) characteristics were measured by using microprobe arrangements, and the diode performance parameters were extracted. The I-V characteristics of the aforementioned configuration exhibited a rectifying contact for the case of Al and Ti metal contacts but an ohmic contact for the case of Sn metal contact. The electroactivity of PANA was carried out in acidic solution, and film morphology was studied by using atomic force microscope. UV-Vis spectroscopic technique was used to obtain the optical bandgap of the polymer. 相似文献
994.
Ravindra Shukla Priyanka Singh Bhanu Prakash Nawal K. Dubey 《International Journal of Food Science & Technology》2013,48(1):128-135
The study explores the efficacy of Acorus calamus L. essential oil (EO) as a safe plant‐based broad spectrum antifungal, antiaflatoxin, antioxidant food additive. The oil completely inhibited the growth and toxin production of the toxigenic strain of Aspergillus flavus at 0.4 and 0.25 μL mL?1, respectively. EO exhibited pronounced antifungal activity against sixteen food‐infesting fungal species at 0.5 μL mL?1. The EO showed strong antioxidant efficacy (IC50 1.06 μL mL?1) and nonphytotoxic nature on germination of chickpea seeds. The EO was found nonmammalian toxic showing high LD50 (4877.4 μL kg?1) for mice (oral, acute). The chemical profile of EO was determined through GC and GC–MS analysis. The findings strengthen the possibility of A. calamus EO as a plant‐based food additive in view of its favourable safety profile, antioxidant and antiaflatoxigenic efficacy and broad spectrum antimicrobial activity against food‐infesting fungi. 相似文献
995.
LiNi1/3Mn1/3Co1/3O2, a high voltage and high-capacity cathode material for Li-ion batteries, has been synthesized by three different rapid synthetic methods, viz. nitrate-melt decomposition, combustion and sol–gel methods. The first two methods are ultra rapid and a time period as small as 15 min is sufficient to prepare nano-crystalline LiNi1/3Mn1/3Co1/3O2. The processing parameters in obtaining the best performing materials are optimized for each process and their electrochemical performance is evaluated in Li-ion cells. The combustion-derived LiNi1/3Mn1/3Co1/3O2 sample exhibits large extent of cation mixing (10%) while the other two methods yield LiNi1/3Mn1/3Co1/3O2 with cation mixing <5%. LiNi1/3Mn1/3Co1/3O2 prepared by nitrate-melt decomposition method exhibits superior performance as Li-ion battery cathode material. 相似文献
996.
本报告曾在2005年德国柏林召开的“欧洲涂料会议”上发表,引起广泛的关注。提出了一种在涂料中高效使用目前杀菌剂的一种新的技术思路及方法,在此推荐给大家,供我国同仁们借鉴和参考。[编者按] 相似文献
997.
Atsuhiko Taniguchi Mariusz Skwarczynski Dr. Youhei Sohma Dr. Takuma Okada Dr. Keisuke Ikeda Halan Prakash Dr. Hidehito Mukai Dr. Yoshio Hayashi Prof. Dr. Tooru Kimura Dr. Shun Hirota Prof. Dr. Katsumi Matsuzaki Prof. Dr. Yoshiaki Kiso Prof. Dr. 《Chembiochem : a European journal of chemical biology》2008,9(18):3055-3065
In biological experiments, poor solubility and uncontrolled assembly of amyloid β peptide (Aβ) 1–42 pose significant obstacles to establish an experiment system that clarifies the function of Aβ1–42 in Alzheimer's disease (AD). Herein, as an experimental tool to overcome these problems, we developed a water‐soluble photo‐“click peptide” with a coumarin‐derived photocleavable protective group that is based on an O‐acyl isopeptide method. The click peptide had nearly 100‐fold higher water solubility than Aβ1–42 and did not self‐assemble, as the isomerized structure in its peptide backbone drastically changed the conformation that was derived from Aβ1–42. Moreover, the click peptide afforded Aβ1–42 quickly under physiological conditions (pH 7.4, 37 °C) by photoirradiation followed by an O–N intramolecular acyl migration. Because the in situ production of intact Aβ1–42 from the click peptide could improve the difficulties in handling Aβ1–42 caused by its poor solubility and highly aggregative nature, this click peptide strategy would provide a reliable experiment system for investigating the pathological function of Aβ1–42 in AD. 相似文献
998.
Heat transfer mechanisms in the bulk and distributor regions of a slurry bubble column are investigated based on the measurements of local heat transfer in a 0.28 m diameter Plexiglas column. The gas, liquid and solid phases used are oil‐free compressed air, tap water and 35 μm glass beads. The slurry concentration and superficial gas velocity are varied from 0 to 40 vol% and 0.05 to 0.30 m/s respectively. Measurements have been made with a fast response heat flux probe which provided local instantaneous heat transfer coefficients. The time‐averaged heat transfer coefficients in the bulk region were on average about 50% higher than the distributor region of the column. The wall region heat transfer coefficients are well predicted by the correlation of Deckwer et al. (1980). Heat transfer mechanism in column centre can be adequately described by the consecutive film and surface renewal model. 相似文献
999.
Prakash N. K. Deenapanray C. S. Athukorala Daniel Macdonald W. E. Jellett E. Franklin V. E. Everett K. J. Weber A. W. Blakers 《Progress in Photovoltaics: Research and Applications》2006,14(7):603-614
This paper investigates the reactive ion etching of SiO2, Si3N4, and Si using CHF3/O2 plasma. In particular, we have characterized the time and rf power dependence of the carrier lifetimes in n‐ and p‐type FZ Si. The time dependence of reactive ion etching (RIE) at different rf powers provide insight into the two competing processes of damage accumulation and damage removal in the near‐surface region of the Si during plasma etching. The carrier lifetime, measured using the quasi‐steady‐state photoconductance (QSSPC) technique, has a quadratic dependence on the rf power, which can be related to changes in the dc self‐bias generated by the plasma at different rf powers. The change in carrier lifetime is similar in both n‐ and p‐type Si of the same doping concentration. Using this fact, together with the electronic properties of defects obtained by deep level transient spectroscopy (DLTS), we have modeled the injection‐dependence of the measured carrier lifetimes using the Shockley–Read–Hall model. The isochronal annealing behavior of plasma etched Si has also been studied. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
1000.
Silicon - In this work, Micro Electro Chemical Machining (μECM) of aluminium alloy (AA) 7075 reinforced with nano silicon carbide particles (1.5 wt.%) has been effectively... 相似文献