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141.
Measurements are presented of the time resolved flux of metallic impurities to a carbon probe placed at the limiter radius of the DITE tokamak. Average fluxes of titanium and molybdenum of the order 4 × 1012 mm?2 s?1 are measured. It is concluded that peaks in the metal flux are correlated with arcing and with disruptions initiated by neutral beam injection. The decrease in flux by almost one order of magnitude compared with earlier studies may be related to a recent redesign of the molybdenum limiters which reduces the minor radius of the plasma. It is observed that the deposit density on the probe is not a linear function of exposure to the plasma and also that insertion of the probe causes a change to the local plasma environment. 相似文献
142.
Endometrial lymphomyeloid cell subsets were evaluated in samples from normal women and from women with abnormal uterine bleeding due to subcutaneous levonorgestrel implants (Norplant) or an intrauterine device (IUD). The frequency of CD3(+), CD68(+), CD43(+) and endometrial granulated lymphoid cells was evaluated by immunohistochemical or phloxine-tartrazine staining of formalin-fixed paraffin-embedded samples. In normal women, cyclic variation in lymphomyeloid subsets was seen. In women using Norplant for contraception, the frequency of CD3(+), CD68(+) and CD43(+) cells was dramatically decreased, compatible with endometrial atrophy. When Norplant users with abnormal bleeding were compared to women without bleeding, however, the number of CD68(+) cells was significantly increased and the number of CD3(+) and CD43(+) cells was preserved, contrary to the hypothesis that this group would show a greater degree of atrophy and hence, tissue fragility. A similar pattern was seen in a preliminary study of women with bleeding associated with use of copper-only IUD contraception, and in samples taken from late secretory and menstrual biopsies from normal cycling women. Whether these changes in endometrial lymphomyeloid cells represent a result of bleeding arising from a common mechanism or rather cause the uterine bleeding is discussed. 相似文献
143.
Ajit Singh Chris B. Saunders Vince J. Lopata Walter Kremers Tom E. McDougall Miyoko Tateishi Minda Chung 《Advanced Performance Materials》1996,3(1):57-73
Electron accelerators are being widely used in industry to process polymeric materials. Their use to cure fiber-reinforced composites is an emerging technology, based on the work done here in Canada, and in France. The advantages of electron curing include ambient temperature curing with reduced internal stress, reduced curing times, and overall cost of savings. In this paper we present a brief review of our work with emphasis on the effects of dose and dose rate, temperature rise during curing, internal stress, voids, properties of matrix resins and a comparison of the properties of electron cured and thermally cured matrices and composites.Abbreviations: kW
kilo-watt
- eV
electron volt
- RTM
resin transfer molding
- SEC
size exclusion chromatography
- Gy
Gray (1 Gy = 100 rad)
- THF
tetrahydrofuran
- AMU
atomic mass unit
-
T
g
glass transition temperature 相似文献
144.
Unmixing fMRI with independent component analysis. 总被引:1,自引:0,他引:1
Independent component analysis (ICA) is a statistical method used to discover hidden factors (sources or features) from a set of measurements or observed data such that the sources are maximally independent. Typically, it assumes a generative model where observations are assumed to be linear mixtures of independent sources and works with higher-order statistics to achieve independence. ICA has recently demonstrated considerable promise in characterizing functional magnetic resonance imaging (fMRI) data, primarily due to its intuitive nature and ability for flexible characterization of the brain function. In this article, ICA is introduced and its application to fMRI data analysis is reviewed. 相似文献
145.
Assessing Glycinin (11S) and β-Conglycinin (7S) Fractions of Soybean Storage Protein by Near-Infrared Spectroscopy 总被引:1,自引:0,他引:1
Stephen R. Delwiche Lester O. Pordesimo Dilip R. Panthee Vincent R. Pantalone 《Journal of the American Oil Chemists' Society》2007,84(12):1107-1115
Soybean breeding programs underway today are addressing the goal of improving the protein profile to benefit the human diet
as well as that of livestock. Glycinin, a globulin storage protein of the meal and designated as the 11S size fraction by
ultracentrifugation, is desirable because of its relative abundance of sulfur-containing amino acids, such as methionine and
cysteine. The current study examined the feasibility of near-infrared (NIR) measurement of glycinin and the other prevalent
protein fraction, β-conglycinin (7S size fraction), as well as the electrophoretically separable sub fractions that comprise
these two components. From a population of 101 F6-derived recombinant inbred lines in a field replicated trial, single whole soybeans were scanned in transmittance (800–1,798 nm,
24 beans/sample × 197 samples total). Additional scanning of the ground meal was performed in reflectance (1,100–2,498 nm).
Partial least squares (PLS) calibrations were developed, using the 24-bean average log(1/T) spectrum for each sample, as well as the average spectrum from duplicate packs of log(1/R) spectra of the meal. The results indicate that NIR prediction of 11S and 7S, as well as the sub fractions thereof, is at
best limited to screening purposes in soybean breeding programs for probable reasons of an inherent lack of spectral specificity
of the protein fractions and a non-constant proportion of soluble-to-total protein.
相似文献
Dilip R. Panthee |
146.
Tomy GT Palace VP Pleskach K Ismail N Oswald T Danell R Wautier K Evans B 《Environmental science & technology》2007,41(14):4913-4918
Juvenile rainbow trout (Oncorhynchus mykiss) were exposed in the laboratory to an environmentally relevant dose of 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) via their diet for 49 days, followed by 154 days of untreated food to examine bioaccumulation parameters, potential biochemical effects, and metabolic products. There was a linear increase in the amount of BTBPE in fish during the uptake phase of the experiment, and an uptake rate constant of 0.0069 +/- 0.0012 (arithmetic mean +/- 1 x standard error) nmoles per day was calculated. The elimination of BTBPE from the fish obeyed first-order depuration kinetics (r2 = 0.6427, p < 0.001) with a calculated half-life of 54.1 +/- 8.5 days. The derived biomagnification factor of 2.3 +/- 0.9 suggests that this chemical has a high potential for biomagnification in aquatic food webs. Debrominated and hydroxylated metabolites were not detected in liver extracts and suggest that either biotransformation or storage of BTBPE-metabolites in the hepatic system of fish is minor or that our exposure time frame was too short. Similar concentrations of circulating thyroid hormones, liver deiodinase enzyme activity, and thyroid glandular histology suggest that BTBPE is not a potent thyroid axis disruptor. 相似文献
147.
Vince M Gabert Willem C Sauer Shaoyan Li Ming-Zhe Fan Meike Rademacher 《Journal of the science of food and agriculture》1996,70(2):247-255
Two experiments were carried out to investigate the effect of feeding diets containing faba beans and peas on pancreatic secretions in young pigs fitted with a pancreatic pouch re-entrant cannula. In Experiment 1, eight barrows, with an average initial weight of 8·5 kg, were fed one of two maize starch-based diets formulated to contain 200 g crude protein (CP) kg−1 according to a completely randomised design. In one of the diets, soya bean meal was the sole protein source; in the other diet, soya bean meal and faba beans (cv Fibro; dark-flowering) each supplied 50% of the dietary CP. In Experiment 2, five barrows, with an average initial weight of 18·1 kg, were fed one of two diets according to a two-period change-over design. The diets were formulated to contain 150 g CP kg−1 with peas (cv Ascona or cv Radley) as the sole protein source. In both experiments, the experimental periods consisted of 8 days: 6 days adaptation followed by a 2 day collection of pancreatic juice. The soya bean meal diet and the faba bean diet contained 0.04 and 0.21% tannins (catechin equivalents), respectively. The trypsin inhibitor activities of the Ascona and Radley pea diets were 0·76 and 3·24 mg of trypsin inhibited per gram, respectively. In both experiments, diet did not affect ( P> 0·05) the pancreatic secretions of nitrogen, protein, amylase, lipase and chymotrypsin. In Experiment 1, specific trypsin activity was higher ( P< 0·05) in pancreatic juice from pigs fed the diet containing soya bean meal and faba beans (53700 units litre−1) than for those fed the soya bean meal diet (41200 units litre−1). However, there was no effect ( P> 0·05) when trypsin activity was expressed as total activity (units 24 h−1). It is concluded that the inclu-sion of faba beans and peas in diets for young pigs has only minor effects on exocrine pancreatic secretions. 相似文献
148.
Chris B. Saunders Alistair A. Carmichael Walter Kremers Vince J. Lopata Ajit Singh 《Polymer Composites》1991,12(2):91-95
Advanced composites, specifically carbon-fiber-reinforced epoxies, are used extensively for a variety of demanding structural applications, primarily because of their high strength-to-weight and stiffness-to-weight ratios, corrosion resistance, and damage tolerance characteristics. Electron beam (EB) treatment can be used to produce useful physical and/or chemical changes in plastics and composites by initiating various polymerization and crosslinking reactions. The advantages of using EB rather than thermal curing for carbon-fiber-reinforced epoxy composites include curing at ambient temperature, reduced curing times, and fewer volatiles. An EB-curable carbon fiber-acrylated epoxy composite is being developed for various applications. The tensile properties of the 14-ply EB-cured epoxy laminate were comparable with the properties of the thermally cured laminates used in the aircraft industry. Research is continuing to develop resin formulations and select coupling agents to improve the compression properties of EB-cured laminates. 相似文献