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11.
Mukherjee A. Ranganathan N. Flieder J. Acharya T. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》1993,1(2):203-214
Describes the architecture and design of a CMOS VLSI chip for data compression and decompression using tree-based codes. The chip, called MARVLE, implements a memory-based architecture for variable length encoding and decoding based on tree-based codes. The architecture is based on an efficient scheme of mapping the tree representing any binary code onto a memory device. A prototype 2-mm CMOS VLSI chip has been designed, verified, and fabricated by the MOSIS facility. The chip has a 512×12 static RAM with an access time of 4 ns and logic circuitry for compression as well as decompression. The chip occupies a silicon area of 6.8 mm×6.9 mm and consists of 49695 transistors. The prototype chip yields a compression rate of 95.2 Mb/s and a decompression rate of 60.6 Mb/s with a clock rate of 83.3 MHz. The VLSI hardware can be used to implement the JPEG baseline compression scheme 相似文献
12.
Ozan Nazim Ciftci Roman Przybylski Magdalena Rudzinska Surya Acharya 《Journal of the American Oil Chemists' Society》2011,88(10):1603-1610
The composition and content of lipids, fatty acids, triacylglycerols, tocopherols and sterols in nine fenugreek genotypes
were analyzed. Lipid content in fenugreek seeds ranged from 5.8 to 15.2%. Major fatty acids were: linoleic acid (45.1–47.5%),
α-linolenic (18.3–22.8%), oleic (12.4–17.0%), palmitic (9.8–11.2%) and stearic (3.8–4.2%) acids. The ratios of n-6 to n-3
fatty acids were between 2.1 and 2.7. Similar fatty acid distribution was observed in all analyzed samples with some deviations.
α-Tocopherol was the predominant component found in the fenugreek lipid antioxidants, and it constituted over 84% of the total
amounts of tocopherols. It amounts ranged from 620 to 910 mg/kg lipids. β-Sitosterol was the major sterol in all samples,
varying from 14,203 to 18,833 mg/kg of lipids. Campesterol and cycloartenol were other major sterols, and these compounds
including β-sitosterol constituted 56–72% of all sterols. Fenugreek seed lipids consisted predominantly triunsaturated (56.9–66.5%)
and diunsaturated (32.2–41.6%) triacylglycerides. Among these components trilinolein (LLL; 12.9–20.5%) dominated followed
by PLL (14.0–20.4%), LnLnO (7.8–17.7%), PLO (5.7–11.6%), OLL (6.9–10.6%), LLLn (3.2–9.6%), and LnLnL (3.5–7.6%). Results of
the study show that fenugreek seed lipids may be a source of a nutraceutical ingredient for food applications. 相似文献
13.
Genes encoding the dihydrolipoyl acetyltransferase (E2) and dihydrolipoyl dehydrogenase (E3) components of the pyruvate dehydrogenase (PDH) multienzyme complex from Bacillus stearothermophilus were overexpressed in Escherichia coli. The E2 component was purified as a large soluble aggregate (molecular mass > 1 x 10(6) Da) with the characteristic 532 symmetry of an icosahedral (60-mer) structure, and the E3 as a homodimer with a molecular mass of 110 kDa. The recombinant E2 component in vitro was capable of binding either 60 E3(alpha2) dimers or 60 heterotetramers (alpha2beta2) of the pyruvate decarboxylase (E1) component (also the product of B. stearothermophilus genes overexpressed in E. coli). Assembling the E2 polypeptide chain into the icosahedral E2 core did not impose any restriction on the binding of E1 or E3 to the peripheral subunit-binding domain in each E2 chain. This has important consequences for the stoichiometry of the assembled complex in vivo. The lipoyl domain of the recombinant E2 protein was found to be unlipoylated, but it could be correctly post-translationally modified in vitro using a recombinant lipoate protein ligase from E. coli. The lipoylated E2 component was able to bind recombinant E1 and E3 components in vitro to generate a PDH complex with a catalytic activity comparable with that of the wild-type enzyme. Reversible unfolding of the recombinant E2 and E3 components in 6 M guanidine hydrochloride was possible in the absence of chaperonins, with recoveries of enzymic activities of 95% and 85%, respectively. However, only 26% of the E1 enzyme activity was recovered under the same conditions as a result of irreversible denaturation of both E1alpha and E1beta. This represents the first complete post-translational modification and assembly of a fully active PDH complex from recombinant proteins in vitro. 相似文献
14.
I Irak L Zangwill V Garden S Shakiba RN Weinreb 《Canadian Metallurgical Quarterly》1996,122(5):690-695
PURPOSE: To investigate the relationship between optic disk topography and intraocular pressure before and after trabeculectomy with confocal scanning laser ophthalmoscopy. METHODS: The eyes of 49 consecutive patients undergoing trabeculectomy at a university-based glaucoma practice underwent preoperative and postoperative imaging using a confocal scanning laser ophthalmoscope (Heidelberg Retina Tomograph). Three images of one eye of each patient were obtained with a 15-degree field of view. Preoperative images were obtained approximately 2 months before surgery (mean +/- SD, 2.4 +/- 1.6 months). Postoperative images were obtained at least 3 months after surgery (mean, 4.5 +/- 2.6 months). RESULTS: Mean preoperative intraocular pressure, postoperative intraocular pressure, and percent change in intraocular pressure respectively were 23.1 +/- 6.8 mm Hg, 12.7 +/- 7.1 mm Hg, and 43.8% +/- 29.9%. A significant association (P < .01) was found between percent decrease in intraocular pressure and decreases in cup area, cup volume, and cup/disk area ratio as well as between percent decrease in intraocular pressure and increases in rim area, rim volume, mean height contour, retinal cross-section area, and height in contour. Between 11.7% and 31.2% of the variability (R2) in these parameters was explained by the percent change in intraocular pressure. Topography changes were more strongly associated with percent change than with mean change in intraocular pressure. We found no association between percent decrease in intraocular pressure and reference plane height or maximum cup depth. CONCLUSIONS: Changes in optic nerve topography were associated with reduction in intraocular pressure after trabeculectomy. 相似文献
15.
Silicon - In this paper, we have studied effect of localised charges on performance of UTBB FDSOI FET. Purpose behind this work is to understand the performance of UTBB FDSOI FET under the... 相似文献
16.
Copolymerization of methacrylic acid (MAA) and ethyl acrylate (EA) was performed by the emulsion polymerization technique in the presence of a mixture of ionic and nonionic emulsifiers, at 85°C, using potassium persulfate as initiator (0.16 wt % of monomer). The molar ratio of MAA : EA varied between 44 : 56 and 54 : 46 in the monomer feed. Copolymers of MAA and EA were synthesized by incorporating diallyl phthalate (DAP) with varying concentrations (0–1.7 mol % of total monomer) in the feed. A copolymer latex of MAA, EA, and DAP was also prepared by the variable feed process. The intrinsic viscosity and gel content were determined. Copolymers were characterized by IR and NMR spectroscopic techniques. The composition of copolymers was determined by 1H‐NMR spectra and sequential distribution from 13C{1H}‐NMR spectra. The pH of the copolymer emulsion varied between 3 and 10 by addition of aqueous ammonia (23% w/w) and its effect on Brookfield viscosity was studied. The effects of copolymer composition, crosslinking agent concentration in the feed, monomer feed process, polymer solid contents, and shear rate on Brookfield viscosity were studied at pH ~ 8. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1430–1441, 2003 相似文献
17.
18.
An efficient and operationally simple method is developed for chemical decontamination of simulant of VX. A new chlorine bearing reagent N,N‐dichloro poly(styrene‐co‐divinyl benzene) sulfonamide was developed to deactivate the simulant of VX in aqueous medium. This decontamination reaction was monitored by gas chromatography (GC), and the products were analyzed by gas chromatography‐mass spectrometry (GC‐MS). This reagent has advantage over earlier reported reagents in terms of effectiveness, stability, nontoxicity, cost, ease of synthesis, recyclablity (collected after filtration, rechlorinated, and used for further reaction), and decontamination of simulant of VX to give single nontoxic product at room temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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20.
Sagarika Acharya 《分离科学与技术》2017,52(10):1660-1669
Solvent extraction of La(III) from acidic nitrate medium has been studied with [A336][NO3–] in kerosene. The factors affecting the extraction of La(III) like equilibration time, nitrate ion, extractant and La(III) concentrations, aqueous acidity, O/A ratio variation, nature of diluent, and temperature have been investigated. McCabe-Thiele diagram has been plotted to find out the actual number of theoretical stages needed for complete extraction of lanthanum. The solvent has been successfully regenerated for further use after stripping of the metal. IR studies of [A336][NO3–] and La(III) loaded [A336][NO3–] have been carried out. Modeling of extraction data has been done using Multiple linear regression analysis and Artificial Neural Network, and the performances have been compared. Error in each case was evaluated in terms of R2 and Root mean squared error (RMSE). Maximum extraction of La(III) was 82% when 0.6 M [A336][NO3–] was used for extraction. About 98% of the metal has been recovered using 0.2 M HNO3 as stripping agent. Extractive separation of La(III) and Sm(III) was maximum (β = 65.2) using 0.1 M [A336][NO3–]. IR studies revealed formation of lanthanum complex in the extraction process. Artificial Neural Network proved to be better over Multiple linear regression in data prediction. 相似文献