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991.
A.?de?Lucas J.?Rincón I.?GraciaEmail author 《Journal of the American Oil Chemists' Society》2003,80(2):181-188
Supercritical CO2 extraction is a viable alternative process for the extraction of high-quality oil from olive husk (also known as olive pomace),
a residue obtained in the production of olive oil. We analyzed the effect of pressure (100–300 bar), temperature (40–60°C),
solvent flow (1–1.5 L/min), and particle size (0.30–0.55 mm) on four important quality parameters of the oil extracted with
CO2: tocopherol concentration, extinction coefficients at 232 and 270 nm, and saponification value. Response surface methodology
was used to obtain mathematical expressions related to the operating variables and parameters studied. Results from these
experiments were also used to design a three-step sequential CO2 extraction procedure to obtain a higher-quality extract. The optimal operational sequence consisted of a first extraction
step at 75 bar for 1 h using 1% (vol/vol) ethanol modifier, followed by a second extraction stage at 350 bar for 2.5 h without
ethanol and a third step, also at 350 bar, for 2.5 h but using ethanol. These extraction conditions obtained an intermediate
fraction of oil with 64% yield and all normal parameters according to European Commission food legislation. This fraction
is suitable without any further refining. On the contrary, the oils obtained by hexane extraction and by conventional supercritical
CO2 extraction at optimal conditions are suitable for human consumption after further refining. This last finding may result
in improved economics of the sequential CO2 extraction process compared to the conventional extraction method with hexane. 相似文献
992.
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
993.
994.
本文是利用OPC(OLE for Process Control)技术,通过公司现有的以太网,实现了组态王数据与远程WINCC的通讯,解决了不同组态软件之间的远程通讯难题. 相似文献
995.
为提高含蜡原油流动性能,从辽河油田附近经受原油污染的土壤中筛选出两株原油降解菌。经过16S rRNA基因序列比对鉴定,菌株为纤维微菌属(Cellulosimicrobiumsp.)和假单孢菌(Pseudomonassp.),命名为7#和12#。将筛选出的7#菌与12#菌优化复配使用,研究结果表明:复配菌对液体石蜡有乳化效果,当复配菌体积比为1∶1时,乳化率最高达到77.5%;最适的生长温度为35~40℃,p H=6~8,最佳接种量(体积分数)为4%,复配菌体积比为1∶1,且培养基在初始pH,即pH=7时复配菌生长状态最佳。复配菌在37℃,pH=7条件下对原油处理7 d后,除蜡率为61.32%,降黏率达到31.58%;显微镜观察蜡晶变小,进一步说明菌株能够降解石蜡,破坏蜡晶结构,提高含蜡原油的流动性能。 相似文献
996.
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
997.
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
998.
介绍400 k t/a硫铁矿制酸装置的挖潜改造。通过调整工艺技术指标,增加少量设备和催化剂,将硫酸装置的生产能力从400 k t/a提高到450 k t/a,改造后各项技术经济指标均达到要求,2005年第1季度实现利润1 479万元,取得了明显的经济效益。 相似文献
999.
本文介绍了一种新型的能在较高压力环境下进行细过滤的PE井口高压滤芯的结构特征、关键技术研究、技术特性,以及应用效果。 相似文献
1000.
S.?M.?NolascoEmail author L.?A.?N.?Aguirrezábal G.?H.?Crapiste 《Journal of the American Oil Chemists' Society》2004,81(11):1045-1051
Tocopherols are natural antioxidants that increase the stability of fat-containing foods and perform important biological
activities. Significant variations (389 to 1873 μg g oil−1) in the total tocopherol concentration of sunflower seed oil have been reported. The main objectives of this work were to
determine the influence of intercepted photosynthetically active radiation on tocopherol concentration during seed filling
and to establish and validate relationships between tocopherol concentration in oil and other quality variables of the seed.
Seven sunflower hybrids were grown under good water and nutritional conditions in two similar experiments carried out in two
contrasting environments. Treatments were applied to modify the amount of radiation intercepted per plant during seed filling
in order to obtain a range in oil yield per plant and its components. Greater per plant intercepted radiation decreased the
tocopherol concentration in oil. Tocopherol concentration decreased when oil weight per seed increased. Tocopherol concentration
stabilized for oil weight per seed higher than 23 mg oil seed−1. This exponential relationship accounted for 73% of the variability in tocopherol concentration (507 to 1203 μg g oil−1) despite differences in hull type, locations, hybrids, and radiation treatments. The proposed relationship acceptably predicted
independent results. Crop management techniques could lead to seeds with greater concentrations of tocopherols. 相似文献