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51.
52.
A supercritical fluid extraction method has been applied to test the feasibility of tocopherol concentration from soybean
sludge with carbon dioxide at temperatures and pressures ranging from 35 to 70°C and 200 to 400 bar, respectively. The supercritical
solubility of the esterified soybean sludge was over 4–6 times greater than that of the original soybean sludge. By a simple
batch-type one-stage method the tocopherols in the esterified soybean sludge could be concentrated up to 40 wt%. The overall
results of the present study show that soybean sludge initially containing about 13–14 wt% tocopherols may require a countercurrent
multistage column to be highly and effectively concentrated. 相似文献
53.
Tall oil, a by-product of the kraft process for pulping softwood, has been shown to have insecticidal properties. In the present study, the active principles in tall oil against the variegated cutworm,Peridroma saucia Hübner, were investigated. GC-MS analysis showed that abietic, dehydroabietic, and isopimaric acids were major resin acid components of crude tall oil and depitched tall oil. When crude tall oil samples of differing resin acid composition were incorporated into artificial diet at a concentration of 2.0% fresh weight, they suppressed larval growth by 45–60% compared to controls. This suppression was significantly (P0.05) correlated with the equivalent contents of abietic, dehydroabietic, isopimaric, and total resin acids. These results were also evident from a diet choice test, showing that the second-instar larvae obviously selected diets with low levels of resin acids when different diets were randomly arranged in a Petri dish. Bioassays with pure resin acids (abietic, dehydroabietic, and isopimaric acids) demonstrated that all individual chemicals have similar bioactivity against this insect. Comparison of the bioactivities of depitched tall oil and an equivalent mixture of pure resin acids in thePeridroma chronic growth bioassay indicated that pure resin acids and depitched tall oil share a common mode of action to this insect. This study confirms that resin acids are major active principles in tall oil against the variegated cutworm, but other chemicals likely also contribute to the bioactivity of tall oil. 相似文献
54.
Richard V. Flor Le Tiet Hecking Brian David Martin 《Journal of the American Oil Chemists' Society》1993,70(2):199-203
Criteria for authentic olive oils were developed from isocratic high-performance liquid chromatography analyses of 99 olive
oils from the major Mediterranean producers in the 1983–1986 crop years. Authentic olive oils include extra virgin, virgin
and pure or refined oils, but exclude all reesterified and adulterated oils. The extra virgin through pure grades will have
a combined area for the LOO (C18:2C18:1C18:1), LOP (C18:2C18:1C16:0), OOO (C18:1C18:1C18:1), POO (C16:0C18:1C18:1), POP (C16:0C18:1C18:1), and SOO (C18:0C18:1C18:1) peaks between 82.0 and 92.6% of the total area (L, linoleic; O, oleic; P, palmitic; S, stearic). Authentic oils will have
ratios of LOO/LOP and OOO/POO that coincide with a line defined by OOO/POO=0.7844(LOO/LOP)+0.0968; correlation coefficient
is 0.885. Authentic oils will not have a trilinolein (LLL) peak over 0.5% in area. Neither triolein (OOO) nor any other single
peak suffices to characterize an olive oil sample as one of the authentic grades. 相似文献
55.
J. Kurashige N. Matsuzaki H. Takahashi 《Journal of the American Oil Chemists' Society》1993,70(9):849-852
The bioreactor system to interesterify edible oils and fats at an ultra-micro aqueous phase of 100 ppm and less was investigated.
The adsorption of lecithin, together with lipase onto a carrier, was effective for conducting the interesterifying reaction
efficiently for oils and fats in micro aqueous phase.
To improve the handling properties of palm oil at rather low temperature, palm oil was blended with canola or soybean oil,
and then these blended oils were modified by enzymatic selective interesterification in a solvent-free, ultra-micro aqueous
bioreactor system with an immobilized lipase that had 1,3-positional specificity. The effects of enzymatic interesterification
were confirmed by triglyceride determination, by solid fat content profiles and by cloud point profiles, which were also compared
to products of chemical interesterification. The improvement in the fluidity of blended oils with canola oil by the enzymatic
reaction was bigger than with soybean oil, and chemical interesterification had no effects on the fluidity of blended oils. 相似文献
56.
水蒸气蒸馏法提取广西百色地区迷迭香茎、叶中的挥发油,利用GC-MS联用仪进行了分析。共分离出36个峰,鉴定了其中31个化学成分,占总含量的97.08%。其主要成分为1,8-桉叶素、α-蒎烯、樟脑、莰烯、α-松油醇、乙酸龙脑酯及龙脑等。 相似文献
57.
The process of grinding soybeans to a fine flour and extracting the flour with hexane was studied on a pilot plant scale.
The crude oil from the pilot plant study had 15 ppm phosphorus and was suitable for physical refining after a light acid pretreatment
and bleaching. The refined oil showed a Lovibond color of 1.4 yellow and 0.3 red. The pilot plant study also showed that grinding
of the soybeans and the separation of solid from miscella were the most difficult steps in solvent extraction with fine flour.
A laboratory study on separation of miscella from meal by aqueous ethanol reduced the hold-up volume, but it did not remove
all the miscella. A test with betacarotene showed that only the miscella outside the flour particles was displaced.
Aqueous ethanol solutions used as a second solvent extracted additional nontriglyceride materials (primarily phospholipids)
from the meal. Also, the free fatty acid content of the oil was increased with aqueous ethanol solution wash. The quality
of the extracted crude oil was lowered by using a second solvent, but it had the advantage of needing only one centrifugation
to separate miscella from meal. 相似文献
58.
Yoshitsugu Kosugi Tsutomu Kunieda Naoki Azuma 《Journal of the American Oil Chemists' Society》1994,71(4):445-448
Rice bran oil containing 30–50% free fatty acid was continually converted to an oil containing more than 75% of triacylglycerol
(TG) by means of immobilized lipase. The reaction was carried out at 60°C for 24 h with dehydration and reactant mixing by
dry nitrogen flow under a positive nitrogen atmosphere. Enzymatic TG synthesis with evaporation by heating was not suitable
because of the increasing peroxide value of the oil.
Part of this article was presented at the annual meeting of the Japan Oil Chemists' Society at Sendai, Japan, October, 16,
1990. 相似文献
59.
Kanit Krisnangkura 《Journal of the American Oil Chemists' Society》1991,68(1):56-58
Equations were developed for the estimation of gross heat of combustion (HG) of triglycerides (TGs) and fatty acid methyl
esters (FAMEs) from their saponification number (SN) and iodine value (IV). HG of TG=1,896,000/SN − 0.6 IV — 1600 and HG of
FAME=618,000/SN − 0.08 IV — 430. When these equations were tested on cottonseed oil, soybean oil, partially hydrogenated soybean
oil, peanut oil, sunflower oil, sunflower oil methyl esters, soybean oil methyl esters and cottonseed oil methyl esters, predicted
HG values agreed well with those reported in the literature. 相似文献
60.
To evaluate the wear condition of machines accurately,oil spectrographic entropy,mutual information and ICA analysis methods based on information theory are presented. A full-scale diagnosis utilizing all channels of spectrographic analysis can be obtained. By measuring the complexity and correlativity,the characteristics of wear condition of machines can be shown clearly. The diagnostic quality is improved. The analysis processes of these monitoring methods are given through the explanation of examples. The availability of these methods is validated and further research fields are demonstrated. 相似文献