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51.
Farrukh Aqil Jeyaprakash Jeyabalan Radha Munagala Iqbal Ahmad David J. Schultz Ramesh C. Gupta 《International journal of molecular sciences》2021,22(12)
Breast cancer (BC) is a leading cause of cancer deaths in women in less developed countries and the second leading cause of cancer death in women in the U.S. In this study, we report the inhibition of E2-mediated mammary tumorigenesis by Cuminum cyminum (cumin) administered via the diet as cumin powder, as well as dried ethanolic extract. Groups of female ACI rats were given either an AIN-93M diet or a diet supplemented with cumin powder (5% and 7.5%, w/w) or dried ethanolic cumin extract (1%, w/w), and then challenged with subcutaneous E2 silastic implants (1.2 cm; 9 mg). The first appearance of a palpable mammary tumor was significantly delayed by both the cumin powder and extract. At the end of the study, the tumor incidence was 96% in the control group, whereas only 55% and 45% animals had palpable tumors in the cumin powder and extract groups, respectively. Significant reductions in tumor volume (660 ± 122 vs. 138 ± 49 and 75 ± 46 mm3) and tumor multiplicity (4.21 ± 0.43 vs. 1.16 ± 0.26 and 0.9 ± 0.29 tumors/animal) were also observed by the cumin powder and cumin extract groups, respectively. The cumin powder diet intervention dose- and time-dependently offset E2-related pituitary growth, and reduced the levels of circulating prolactin and the levels of PCNA in the mammary tissues. Mechanistically, the cumin powder diet resulted in a significant reversal of E2-associated modulation in ERα, CYP1A1 and CYP1B1. Further, the cumin powder diet reversed the expression levels of miRNAs (miR-182, miR-375, miR-127 and miR-206) that were highly modulated by E2 treatment. We analyzed the composition of the extract by GC/MS and established cymene and cuminaldehyde as major components, and further detected no signs of gross or systemic toxicity. Thus, cumin bioactives can significantly delay and prevent E2-mediated mammary tumorigenesis in a safe and effective manner, and warrant continued efforts to develop these clinically translatable spice bioactives as chemopreventives and therapeutics against BC. 相似文献
52.
Shalu Kataria Yogendra L. Verma Himani Gupta Shishir K. Singh Nitin Srivastava Ravindra Dhar 《Polymer-Plastics Technology and Engineering》2020,59(9):952-958
ABSTRACTNano-composite polymer gel electrolytes (NPGEs) based on polymer poly(vinylidene fluoride-co-hexafluoropropylene) PVdF-HFP, ionic liquid, 1-butyl-3- methylimidazolium bis(trifluoromethanesulfonyl)imide BMIMTFSI, Li-salt along with the addition of SiO2 nanoparticles have been synthesized and characterized by various techniques. Prepared NPGEs show high room temperature ionic conductivity (~10?3 S/cm) and have a wide electrochemical window (ECW) (~3.3–3.5 V). The galvanostatic charge/discharge profile was studied by sandwiching best performing NPGEs between a LiFePO4 cathode and lithium metal anode. The specific discharge capacity of the cell (Li/NPGE/LiFePO4) room temperature at 0.1C rate is found to be 138 mAh/g. 相似文献
53.
54.
Experimental data on the monomer conversion, xm, and the weight average molecular weight, Mw, have been generated under several isothermal and non-isothermal conditions for the polymerization of methyl methacrylate in a rheometer-reactor assembly. The non-isothermal results, in particular, can be used to provide more stringent tests of kinetic models than isothermal data alone. A simple empirical model has been used to describe this system that accounts for the gel (Trommsdorff) and glass effects. The model involves only xm and the temperature, and is quite general. The model parameters are tuned using only three sets of isothermal data. Good agreement is found between the experimental results and model predictions for a whole variety of experimental conditions, including non-isothermal operation and with intermediate addition of initiator. Because of its generality, this model is quite suitable for use for on-line optimizing control as well as for describing industrial reactors. 相似文献
55.
Determination of Binder Decomposition Kinetics for Specifying Heating Parameters in Binder Burnout Cycles 总被引:2,自引:0,他引:2
The decomposition kinetics of poly(vinyl butyral) binder from barium titanate multilayer ceramic capacitors with platinum metal electrodes were analyzed by thermogravimetric analysis as a function of the heating rate. The activation energy and pre-exponential factor for the decomposition kinetics were determined from two types of integral equations, from the Redhead method, and from the variation in heating rate method. The accuracy of the kinetic parameters determined from these methods was then evaluated for describing the observed rate of binder decomposition. Although the individual models yielded very different kinetic parameters, all were capable of describing the experimental data within ±15% accuracy. The kinetic parameters were then used in a coupled transport and kinetic model for describing the buildup of pressure within the ceramic green body as a function of the heating cycle. A methodology based on calculus of variations was also developed to predict the minimum duration for the binder burnout cycle. 相似文献
56.
A commonly used energy-efficient nylon 6 reactor is simulated under steady-state conditions. The effects of various operating conditions and parameters, e.g., feed composition, temperature and flow rate, heat transfer coefficients, and reactor dimensions, on the temperature and molecular weight profiles are studied. A temperature maximum is observed in the reactor under usual conditions of operation. The maximum value of the temperature is sensitive to the feed conditions, and one has to ensure that degradation reactions speeded up at high temperatures do not affect product characteristics. The model and the numerical technique used are fairly simple and account for most of the important features of industrial reactors. Hence, these can be used in the development of digital-control algorithms in the future. 相似文献
57.
A. R. Pal D. P. Motiramani S. B. Gupta B. S. Bhargava 《Nutrient Cycling in Agroecosystems》1990,22(3):129-136
Attempts were made to find out the nature and cause of a widespread sugarcane chlorosis in a cane growing area. Soils from chlorotic and nonchlorotic fields did not differ markedly in pH, CaCO3, electrical conductivity, organic C, and soil test P, Zn, Cu, and Mn levels, but the chlorotic field soils had relatively more NH4OAc-extractable K and less clay and DTPA-extractable Fe. Chlorotic and green leaf blades contained about the same concentration of P, S, Mg, Fe, Zn, Cu, and Mo, but the former leaf blades had more K and less Ca and HCl soluble Fe than the green ones. Green leaves of plants that seemed to have naturally recovered in chlorotic fields were higher in Mn. A foliage spray with 2.5% FeSO4.7H2O solution resulted in greening of leaves and a field experiment showed marked crop response to Fe and some response to Mn. The results thus suggest that the chlorosis is due to a lime-induced Fe-deficiency with the possibility of some role of Mn in Fe nutrition in calcareous soil conditions.Deceased 22 September 1988 相似文献
58.
The measurements of ac conductivity [σm(ω)], dielectric constant [?′(ω)] and loss [?″(ω)] have been performed on solution grown (thickness ∼85 μm) and uniaxially stretched (thickness ∼25, 45 and 80 μm) films of poly(vinylidene fluoride) (PVDF) in the frequency range 0.1 kHz-10 MHz and in the temperature range 77-400 K. The σm(ω) can be described by the relation σ(ω) = Aωs, where s is close to unity and decreases with increase in temperature. Three relaxations, observed in the present investigation, have been designated as the αc-, the αa- and the β-relaxations appearing from high temperature side to the low temperature side. The αc-relaxation could not be observed in the case of uniaxially stretched poly(vinylidene fluoride) films. The αc- and αa-relaxations are associated with the molecular motions in the crystalline regions and micro-Brownian motion in the amorphous regions of the main polymer chain, respectively, whereas the β-relaxation is attributed to the rotation of side group dipoles or to the local oscillations of the frozen main polymer chain. 相似文献
59.
The thermal degradation of cellulose and its phosphorylated products (phosphates, diethylphosphate, and diphenylphosphate) were studied in air and nitrogen by differential thermal analysis and dynamic thermogravimetry from ambient temperature to 750°C. From the resulting data various thermodynamic parameters were obtained following the methods of Broido and Freeman and Carroll. The values of Ea for decomposition for phosphorylated cellulose were found to be in the range 55–138 kJ mol?1 in air and 85–152 kJ mol?1 in nitrogen and depended upon the percent of phosphorus contents in the samples. The mass spectrum of cellobiose phosphate indicated the absence of the molecular ion, indicating that the compound was thermally unstable. The IR spectra of the pyrolysis residues of cellulose phosphate gave indication of formation of a compound having C?O and P?O groups. A fire retardancy mechanism for the thermal degradation of cellulose phosphate has been proposed. 相似文献
60.
The pyrolysis under nitrogen of salt free and salt treated cellulose was studied by infrared spectroscopy. The results confirm the unzipping mechanism suggested by DTA and TGA studies, and show this mechanism to apply to the untreated and salt treated samples. The results also show the unzipping to stop at the stage of char formation. The onset of this stage was found to occur after the volatilization of only 45–50% of the initial sample of the borax treated cellulose, compared with 65–70% of the KCl treated cellulose and 80–85% of the untreated cellulose. 相似文献