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91.
Syed Safdar Ali Khalid Mohammed Khan Hartmut Echner Wolfgang Voelter Mashooda Hasan Atta-ur-Rahman 《Advanced Synthesis \u0026amp; Catalysis》1995,337(1):12-17
Two new synthons, Fmoc-L-Arg(biphenyl-4-sulphonyl)-OH ( 8 ) and Fmoc-Arg(4-methoxy-3-t-butylbenzenesulphonyl)-OH ( 14 ), are prepared for the synthesis of arginine-containing peptides. These groups are cleaved by commonly employed trifluoroacetic acid and methanesulphonic acid. Kinetic studies reveal that extended bicyclic aromatic conjugation, as in biphenyl, slightly improves the acid lability compared to the electron-donating t-butyl group. 相似文献
92.
Osamah M. Belali Mohammed M. Ahmed Mohamed Mohany Tarig M. Belali Meshal M. Alotaibi Ali Al-Hoshani Salim S. Al-Rejaie 《International journal of molecular sciences》2022,23(3)
The present study is designed to determine the effect of LCZ696 on DCM in rats and investigate the underlying mechanism involved. Diabetes was induced by feeding rats with a high-fat diet for six weeks following a single injection of STZ (30 mg/kg). Diabetic rats were divided into three groups (n = 10). LCZ696 and valsartan treatment was started two weeks after diabetic induction and continued for eight weeks. At the end of the treatment, serum and cardiac tissues were analyzed by RT-PCR, Western blot, and ELISA kits. LCZ696 and valsartan ameliorated DCM progression by inhibiting AGEs formation at activity levels; pro-apoptotic markers (BAX/Bcl2 ratio and caspase-3) in mRNA and protein expressions, the NF-κB at mRNA; and protein levels associated with the restoration of elevated proinflammatory cytokines such as the TNF-α, IL-6, and IL-1β at the activity level. Furthermore, LCZ696 and valsartan contribute to restoring the induction of ER stress parameters (GRP78, PERK, eIF2a, ATF4, and CHOP) at mRNA and protein levels. LCZ696 and valsartan attenuated DCM by inhibiting the myocardial inflammation, ER stress, and apoptosis through AGEs/NF-κB and PERK/CHOP signaling cascades. Collectively, the present results reveal that LCZ696 had a more protective solid effect against DCM than valsartan. 相似文献
93.
Mohammed Al-Duais Lars Müller Volker Böhm Gottfried Jetschke 《European Food Research and Technology》2009,228(5):813-821
In the framework of standardisation of new healthy food sources, this paper aimed to study the total phenolics and the antioxidant
power of Cyphostemma digitatum (Vitaceae) in water and ethanol extracts, using 96-well micro plates with BMG FLUOstar Optima micro plate reader. Total phenolics
by Folin–Ciocalteu method in the water extracts were significantly lower after processing, decreasing from 1.41 ± 0.06 g GAE/100 g
in the raw leaves to 0.80 ± 0.08 g GAE/100 g in the processed sample; the ethanol extract revealed the same trend with higher
values, decreasing from 1.95 ± 0.03 to 1.56 ± 0.12 g GAE/100 g. The antioxidant capacity was elucidated by four methods: TEAC,
DPPH, FRAP and ORAC. No or very weak correlations were found between antioxidant assays and total phenolics; this confirms
that the antioxidant capacity could be attributed to other molecules. The ORAC assay proved to be more powerful than the other
assays; it showed 103.3 ± 2.5 mmol/100 g Trolox equivalents in the raw leaves ethanol extract and 91.9 ± 3.0 mmol/100 g in
the processed sample. ORAC assay showed the opposite for the water extract where the antioxidant capacity increased from 16.7 ± 0.2
to 41.7 ± 2.7 mmol/100 g Trolox equivalents after processing, which could be attributed to new water-soluble compounds generated
in the consumed form. 相似文献
94.
Energy demand of India is continuously increasing. Coal is the major fossil fuel in India and continues to play a pivotal role in the energy sector. India has relatively large reserves of coal (253 billion tonnes) compared to crude oil (728 million tonnes) and natural gas (686 billion cubic meters). Coal meets about 60% of the commercial energy needs and about 70% of the electricity produced in India comes from coal, and therefore there is a need for technologies for utilization of coals efficiently and cleanly. UCG offers many advantages over the conventional mining and gasification process. UCG is a well proven technology. Due to the site-specific nature of the process, possibility of land subsidence and surrounding aquifer water contamination, this technology is still in a developing stage in India. Potential for UCG in India is studied by comparing the properties of Indian coals with the properties of coal that are utilized by various UCG trials. The essential issues are elaborated for starting UCG in India based on the reported information from the successful field trials conducted all over the world. Indian industries are in the process of initiating pilot studies of UCG at various sites. This study will help to motivate both applied and theoretical research work on UCG sites in India and after detailed analysis it will provide basic data to interested industries. 相似文献
95.
Two types of silicon (Si) substrates (40 n-type with uniform base doping and 40 n/n+ epitaxial wafers) from the silicon industry rejects were chosen as the starting material for low-cost concentrator solar cells. They were divided into four groups, each consisting of 20 substrates: 10 are n/n+ and 10 are n substrates, and the solar cells were prepared for different diffusion times (45, 60, 75 and 90 min). The fabricated solar cells on n/n+ substrates (prepared with a diffusion time of 75 min) showed better parameters. In order to improve their performances, particularly the fill factor, 20 new solar cells on n/n+ substrates were fabricated using the same procedure (the diffusion time was 75 min)—but with four new front contact patterns. Investigation of current–voltage (I–V) characteristics under AM 1.5 showed that the parameters of these 20 new solar cells have improved in comparison to previous solar cells' parameters, and were as follows: open-circuit voltage (VOC=0.57 V); short circuit current (ISC=910 mA), and efficiency (η=9.1%). Their fill factor has increased about 33%. The I–V characteristics of these solar cells were also investigated under different concentration ratios (X), and they exhibited the following parameters (under X=100 suns): VOC=0.62 V and ISC=36 A. 相似文献
96.
The electrochemical promotion of catalysis (EPOC) was used to promote the selective reduction of NO by hydrocarbons in presence of oxygen using thin (40 nm) porous Rh and Pt catalyst layers sputtered on the opposite surfaces of thin (0.25 mm) solid electrolyte (YSZ) plates serving as electrocatalytic elements of a monolithic electrochemically promoted reactor (MEPR). Using 22 Rh/YSZ/Pt type cells it was found that the reduction of NO in presence of 1.1 kPa O2 and 0.36 kPa C2H4 can be efficiently electropromoted with 340% rate enhancement, reaching 95% NO conversion with 100% selectivity to N2 in the temperature range from 280 to 340 °C. The apparent Faradaic efficiency is larger than unity for both the NO reduction and the C2H4 oxidation reaction.At elevated temperatures (≥300 °C) and high reactant conversions it was found that after current interruption, the catalytic rates do not return to their initial values but remain in a new highly active steady state. It appears that this highly active state is not a genuine intrinsic permanent NEMCA state but is manifestation of steady-state multiplicity in the monolithic reactor resulting from near complete gaseous O2 consumption. Thus the low and high activity steady states corresponding to zero applied potential appear to correspond to high and low average PO2 in the reactor. The latter is the result of the near complete reactant conversion under the preceding electropromoted operation. These highly active permanent NEMCA states may be quite useful for practical applications. 相似文献
97.
A numerical study has been carried out to investigate the effect of aspect ratio on heat transfer by natural convection of nanofluid taking Cu nano particles and the water as based fluid. The flow is laminar, steady state, axisymmetric two-dimensional in a vertical cylindrical channel filled with porous media. Heat is generated uniformly along the center of the channel with its vertical surface remain with cooled constant wall temperature and insulated horizontal top and bottom surfaces. The governing equations which used are continuity, momentum and energy equations using Darcy law and Boussinesq's approximation which are transformed to dimensionless equations. The finite difference approach is used to obtain all the computational results using the MATLAB-7 program. The parameters affected on the system are Rayleigh number ranging within (10≤ Ra ≤ 103), aspect ratio (1 ≤ As 〈 5) and the volume fraction (0 ≤0 〈 0.2). The results obtained are presented graphically in the form of streamline and isotherm contour plots and the results show that as ~ increase from 0.01 to 0.2 the value of the mean Nusselt number increase 50.4% for Ra = 1,000. 相似文献
98.
Hamdi M. Hassaneen Mohammed S. Algharib Ahmed M. Farag Ahmed S. Shawali 《Advanced Synthesis \u0026amp; Catalysis》1988,330(4):558-562
Reaction of C-ethoxycarbonyl-N-arylnitrilimines ( 2a–d ) with α, β-disubstituted acrylonitriles ( 3a–f ) in refluxing benzene affords the corresponding substituted pyrazoles 5a–f and 6a–c respectively in good yield. However, reaction of 2a–e with 3g gives the 2-pyrazoline derivatives 7a–d . The assigned structures for the products 5–7 were confirmed by their spectra (i.r., 1H-n.m.r.) and elemental analyses. Also the structures of the pyrazoles 5 were substantiated by comparison with their regioisomeres 8 . 相似文献
99.
E. Fanghnel R. Radeglia K.-H. Bedemann H. Mohammed J. Kriwanek P. Steinmüller 《Advanced Synthesis \u0026amp; Catalysis》1985,327(4):627-632
About the Reaction of N-Aryl-2,4-dimethyl-buta-1,3-dien-1,4-sultames with Tetracyanoethylene; 1H, 13C and 15N N.M.R. Spectroscopic Charcterization of the Products of Tetracyanethylation and Tricyanvinylation The 4-methyl group in N-aryl-2, 4-dimethyl-buta-1,3-dien-1, 4 sultames is C H-acidic and adds therefore to tetracyanethylene. The adducts easily lose HCN on dissolving in DMSO to form N-aryl-2-methyl-4-(2, 3, 3-tricyanoprop-2-ene-1-ylidene)-but-2-en-1, 4-sultames 4 , which form sodium salts at C-1. The structures of the compounds obtained were determined by 13C and 15N n.m.r. spectroscopy. 相似文献
100.
E. Fanghnel H. Mohammed A. M. Richter R. Radeglia 《Advanced Synthesis \u0026amp; Catalysis》1984,326(4):545-555
About Chlorination of N-Aryl-2,4-dimethyl-buta-1,3-dien-1,4-sultames The sultames of structure 1 are easily chlorinated by sulfurylchloride, chlorine or tertbutylhypochlorite. The structure of the mono-( 2a-c,3a, d ), di-( 4a-d ), tri- ( 5c, d ) and pentachlorosultames ( 6a, b ) is determined by 13C-n.m.r. spectroscopy. Contrary to the bromination the chlorination (by SO2Cl2) starts with the substitution of the sultamring (formation of mono- and di-chlorosultames) followed of the substitution of the (C-4)-CH3- group (formation of trichlorosultames). By 1,4-addition of an other molecule of chlorine to 5 the pentachlorosultames 6a, b are obtained. Already by recrystalisation of 6a, b in an alcohol the chlorine in 4-position is exchanged by the corresponding alkoxy group (CH3O, C2H5O, n-C3H7O) and the compounds 7-9 are formed. 相似文献