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101.
A technique is described for bonding gold and silver metals onto sapphire. This technique has been successfully used in ac calorimetry for heat capacity of films. 相似文献
102.
In the course of a recent investigation of the kinetics of grain boundary migration in copper bicrystals, formation of annealing
twins, faceting and grain boundary pinning have been observed. Stability and frequency of formation of annealing twins are
related to boundary misorientation and temperature of anneal. Tendency for grainboundary faceting decreases with increasing
temperature indicating that anisotropy of grain boundary energy is more pronounced at lower temperatures. In general, orientations
of faceted boundaries corresponded to higher-order twin planes with respect to shrinking grains. At relatively high temperatures
(950°C), specimen-thickness-dependent pinning effects also are observed. These observations are described and analyzed in
terms of grain boundary structure, energy, and migration behavior. 相似文献
103.
A modification of the DLTS (Deep Level Transient Spectroscopy) technique for interface-state measurement is described in which the surface potential is used to determine the energy of the interface states contributing to the emission signal. This technique allows an accurate and unambiguous determination of interface-state energies and cross sections. Expressions are determined for interface-state emission as a function of surface potential. Measurements of interface-state density and majority-carrier cross sections as functions of energy for n- and p-type MOS samples are presented. 相似文献
104.
105.
S. Mariccor A. B. Batoy Sabine Borgmann Karin Flick Josephine Griffith Jeffrey J. Jones Viswanathan Saraswathi Alyssa H. Hasty Peter Kaiser Charles L. Wilkins 《Lipids》2009,44(4):367-371
Here we describe a study of the feasibility of lipid and phospholipid (PL) profiling using matrix assisted laser desorption/ionization
(MALDI) Fourier transform mass spectrometry (FTMS) for two different applications. In this work PL profiles of different mammalian
tissues as well as those of whole cell organisms were examined. In particular, comparative analysis of lipid and PL profiles
of tissues from mice fed different diets was done and, in another application, MALDI FTMS was used to analyze PL profiles
of genetically modified Saccharomyces cerevisiae. Computational sorting of the observed ions was done in order to group the lipid and PL ions from complex MALDI spectra.
The PL profiles of liver tissues from mice fed different diets showed a cross correlation coefficient of 0.2580, indicating
significant dissimilarity, and revealed more than 30 significantly different peaks at the 99.9% confidence level. Histogram
plots derived from the spectra of wild type and genetically modified yeast resulted in a cross correlation coefficient 0.8941
showing greater similarity, but still revealing a number of significantly different peaks. Based on these results, it appears
possible to use MALDI FTMS to identify PLs as potential biomarkers for metabolic processes in whole cells and tissues. 相似文献
106.
Pulipparambil Vasu Divya Divakaran Ambika Dhanya Krishnan Kalathil Sivanandan Viswanathan Kumar 《International Journal of Applied Ceramic Technology》2009,6(2):231-235
Ferroelectric glass–ceramics of composition 0.90 (Ba0.7 Sr0.3 ) TiO3 –0.10(B2 O3 :SiO2 ) (0.90 BST:0.10 BS) synthesized by sol–gel method have been used for the preparation of dielectric thick-film inks. The particle dispersion of the glass–ceramic powders in the thick-film ink formulations have been studied through rheological measurements for fabricating thick-film capacitors by screen printing technique. The thick films derived from such glass–ceramics are found to sinter at considerably lower temperatures than the pure ceramic, and exhibit good dielectric characteristics with a tunability of 32% at 1 MHz under a dc bias field of 35 kV/cm. 相似文献
107.
S. Navaladian B. Viswanathan T. K. Varadarajan R. P. Viswanath 《Nanoscale research letters》2009,4(2):181-186
Palladium nanoparticles of average size around 8 nm have been synthesized rapidly by UV irradiation of mixture of palladium
chloride and potassium oxalate solutions. A rod-shaped palladium oxalate complex has been observed as an intermediate. In
the absence of potassium oxalate, no Pd nanoparticles have been observed. The synthesized Pd nanoparticles have been characterized
by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), selective area electron diffraction and energy
dispersive analysis by X-rays (EDAX) analyses. XRD analysis indicates the preferential orientation of catalytically active
{111} planes in Pd nanoparticles. A plausible mechanism has been proposed for the formation of anisotropic Pd nanoparticles. 相似文献
108.
S. Navaladian B. Viswanathan T. K. Varadarajan R. P. Viswanath 《Nanoscale research letters》2009,4(5):471-479
Worm-like nanorods and nanospheres of silver have been synthesized by photochemical decomposition of silver oxalate in water
by UV irradiation in the presence of CTAB and PVP, respectively. No external seeds have been employed for the synthesis of
Ag nanorods. The synthesized Ag colloids have been characterized by UV-visible spectra, powder XRD, HRTEM, and selected area
electron diffraction (SAED). Ag nanospheres of average size around 2 nm have been obtained in the presence of PVP. XRD and
TEM analyses revealed that top and basal planes of nanorods are bound with {111} facets. Williamson–Hall plot has revealed
the presence of defects in the Ag nanospheres and nanorods. Formation of defective Ag nanocrystals is attributed to the heating
effect of UV-visible irradiation. 相似文献
109.
Hernán Valle Raquel Palao-Suay María Rosa Aguilar Julio San Román José Becerra Bernabé Rivas Ramalinga Viswanathan Mangalaraja 《应用聚合物科学杂志》2019,136(20):47545
In this article, an improved synthesis strategy of the potent anticancer compound 4,7-dichloro-2-quinolinemethanol (QM) and its acrylate ester 4,7-dichloro-2-quinolinemethylacrylate (AQM) are described. AQM is copolymerized using free-radical polymerization with N-vinyl-2-pyrrolidone (VP) and the copolymers obtained from different molar ratios of monomers are subjected to nanoprecipitation to produce suspensions of nanoparticles (NPs) in phosphate buffered saline (PBS). The smallest and stable NPs are prepared with the AQM-VP copolymers 45:55 and 40:60 (118.9 and 128.7 nm in diameter, respectively) at 1 mg mL−1, and along with AQM and QM, are evaluated for their cytotoxic activity on MDA-MB-453 breast carcinoma cells using MTT bioassay. AQM and QM are highly cytotoxic (IC50: 19 and 41 μM, respectively); however, the NPs are not cytotoxic in the range of the assayed concentrations. These results contribute to the search for new polymeric NPs with potential application as QM delivery systems for the treatment of cancer or other diseases treatable with QM. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47545. 相似文献
110.