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41.
Simulation at the gate level is computationally very expensive.Parallel processing is one technique to reduce simulation time.Possessing knowledge of the distribution of computational activity insimulation can aid in parallelizing it efficiently. We present a newcharacterization of the distribution of the computational workload infault simulation. An empirical analysis shows that the workloaddistribution is circuit specific, and is largely independent of thevector set being simulated. An inexpensive method to predict theworkload distribution is also discussed. 相似文献
42.
A total of 12 glass-ionomer cement specimens were utilized in the present study. The specimens were divided into two equal groups. The first group was used after 10 minutes from setting, while the second was utilized after 24 hours from setting. Each group was divided into three equal subgroups (2 specimens each). The first subgroups were finished under wet condition (wet finished). The second subgroups were dry finished. On the other hand, the third subgroups were kept undisturbed (as set) under mylar strips. The specimens surfaces were then examined by a Scanning Electron Microscope (SEM). It was found that, finishing of the specimens after 24 hours from setting demonstrated more acceptable surface topography either in wet or dry conditions than finishing after 10 minutes from setting. Moreover, the dry finished specimens displayed more acceptable surface topography than the wet finished specimens. On the other hand, the as set (undisturbed) specimens the most acceptable surface topography. 相似文献
43.
Kilgore Heath; Sideman Lawrence; Amin Kiran; Baca Louise; Bohanske Bob 《Canadian Metallurgical Quarterly》2005,42(3):395
Psychologists' attitudes and approaches toward the gay, lesbian, and bisexual (GLB) lifestyle continue to change, on the basis of results from 437 responding members of the American Psychological Association. Psychologists are more likely to view an active GLB lifestyle-identity as acceptable and non-pathological, more likely to support and provide gay-affirmative therapy, and much less likely to support changing sexual orientation through psychotherapy. Female psychologists are significantly more likely to view a GLB lifestyle as accepting and to provide gay-affirmative therapy to GLB clients compared with their male counterparts. Finally, training opportunities for psychologists involving GLB issues appear to be increasing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Phosphatic materials of agronomic interest were synthesised. These materials of good mechanical quality and of significant porosity show high P2O5 contents (up to 28%). They have been prepared by treatment of volcanic pumices with a solution of phosphoric acid (1N, 5N or 10N) at 200°C in a closed system for 72h using a mass solid/liquid ratio of 1:3.After reaction, the precipitation of amorphous phosphates and crystalline aluminium phosphates has been detected by XRD both outside and inside of the material. The morphological study by SEM reveals several crystalline forms of aluminium phosphates: crystals of small size migrate into the internal porosity of the pumices and crystals of berlinite appear (AlPO4) well developed in a matrix of amorphous phosphate overlapping the initial material.Normal tests of reactivity in water and in 2% citric acid show that the percentages of released P2O5 in solution are greater after treatment with weak concentrations of phosphoric acid. Lixiviation of treated materials with citric acid reagent shows that, after three days of reaction, losses in weight are considerable and the kinetic curves of phosphorus liberation present a linear evolution.The fertilizing value of these materials did not decrease during the leaching; so phosphorus will be solubilized with time thus allowing these materials to gain a good agronomical availability and to propose their use as delayed fertilizer types for tropical agricultural soils. 相似文献
45.
Chemical composition and antioxidant properties of Laurus nobilis L. and Myrtus communis L. essential oils from Morocco and evaluation of their antimicrobial activity acting alone or in combined processes for food preservation 总被引:1,自引:0,他引:1 下载免费PDF全文
46.
Barzegar Hassan Alizadeh Behbahani Behrooz Mehrnia Mohammad Amin 《Food science and biotechnology》2020,29(5):717-728
Food Science and Biotechnology - The instability and strong flavor or odor of essential oils (EO) limit their direct incorporation into food products. In this study, the antioxidant and... 相似文献
47.
A highly efficient solvent-free and simple one-pot approach for the synthesis of 4-hydroxythiazolidine-2-thione is described. The reaction of primary amines and carbon disulfide in the presence of 2-chloroacetaldehyde afforded the title compounds in high yields. 相似文献
48.
E.M.M. Ewais N.M. Khalil M.S. Amin Y.M.Z. Ahmed M.A. Barakat 《Ceramics International》2009,35(8):3381-3388
Four calcium aluminate cement mixes were manufactured from aluminum sludge as a source of calcium oxide and Al2O3 and aluminum slag (dross) as a source of aluminum oxide with some additions of pure alumina. The mixes were composed of 35–50% aluminum sludge, 37.50–48.75% aluminum slag (dross) and 12.50–16.25% aluminum oxide. The mixed were processed then sintered at different firing temperatures up to 1500 °C or 1550 °C. The mineralogical compositions of the fired mixes investigated using X-ray diffraction indicated that the fired mixes composed of variable contents of calcium aluminate (CA), calciumdialuminate (CA2), calciumhexaaluminate (CA6) in addition to some content of magnesium aluminate spinel (MA). Sintering parameters (bulk density, apparent porosity and linear change) and mechanical properties (cold crushing strength) of the fired briquettes were tested at different firing temperature. Refractoriness of the cement samples manufactured at the optimum firing temperature was detected. Cementing properties (water of consistency, setting time and compressive strength as a function of curing time up to 28 days of hydration) of pasted prepared from the manufactured cement mixes at the selected optimum firing temperatures (1400 °C or 1500 °C) were also tested. Cement mixes manufactured from 45 to 50% aluminum sludge, 37.50–41.25% aluminum slag (dross) with 12.50–13.75% alumina were selected as the optimum mixes for manufacturing calcium aluminate cement since they satisfy the requirements of the international standard specifications regarding cementing and refractory properties as a result of their content of CA (the main hydraulic phase in calcium aluminate cement) and CA2(the less hydraulic but more refractory phase). Although the recognized high refractoriness of CA6, its formation affect badly the cementing properties of the other non-optimum mixes. 相似文献
49.
Laminar mixed convection of a nanofluid consisting of water and Al2O3 in an inclined tube with heating at the top half surface of a copper tube has been studied numerically. The bottom half of
the tube wall is assumed to be adiabatic (presenting a tube of a solar collector). Heat conduction mechanism through the tube
wall is considered. Three-dimensional governing equations with using two-phase mixture model have been solved to investigate
hydrodynamic and thermal behaviours of the nanofluid over wide range of nanoparticle volume fractions. For a given nanoparticle
mean diameter the effects of nanoparticle volume fractions on the hydrodynamics and thermal parameters are presented and discussed
at different Richardson numbers and different tube inclinations. Significant augmentation on the heat transfer coefficient
as well as on the wall shear stress is seen. 相似文献
50.
Javad Sargolzaei Amin Hedayati Moghaddam Jalal Shayegan 《Korean Journal of Chemical Engineering》2011,28(9):1889-1896
The present work deals with application of 25-2 fractional factorial design (FFD) to evaluate the operating parameters on starch separation from synthetic starchy wastewater
using a hydrophilic polyethersulfone membrane with 0.65 μm pore size in a plate and frame handmade membrane module. The analysis
of variance (ANOVA) combined with F-test was also used to recognize non-significant terms. The performance of the filtration process was evaluated by calculating
the COD removal percentage (rejection factor) and permeate flux. In this experiment, five input parameters were surveyed,
including trans membrane pressure (TMP), flow and temperature of feed, pH and concentration of wastewater. In this experiment,
real wastewater was not used but synthetic starchy wastewater was prepared using starch. Two models were obtained from experimental
data, capable of predicting COD removal percentage and permeate flux in different conditions. The predicted values obtained
from the regression models were close to the actual ones. For the reduction of fouling, cleaning in place (CIP) method was
used. 相似文献