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61.
62.
A. Proctor C. Adhikari G. D. Blyholder 《Journal of the American Oil Chemists' Society》1995,72(3):331-335
Fourier transform infrared spectroscopy was used to investigate the adsorption of oleic acid (OA) onto dry rice hull ash (RHA)
silica. Adsorption partially occurred by surface hydrogen bonding of the carboxylic acid. There was also formation of carboxylate
ions by reaction of OA with residual potassium oxide. These ions were strongly bound by the ash. Isopropanol inhibited OA
adsorption by H-bonding and encouraged desorption of H-bonded OA, but without itself being significantly bound. RHA with 40%
moisture also adsorbed a small amount of OA by H-bonding and reacted with OA to form and adsorb carboxylate ions. 相似文献
63.
Darrell Sparks Rafael Hernandez Mark Zappi Dean Blackwell Trey Fleming 《Journal of the American Oil Chemists' Society》2006,83(10):885-891
Extraction of rice bran lipids was performed using supercritical carbon dioxide (SC−CO2) and liquid propane. To provide a basis for extraction efficiency, accelerated solvent extraction with hexane was performed
at 100°C and 10.34 MPa. Extraction pressure was varied for propane and SC−CO2 extractions. Also, the role of temperature in SC−CO2 extraction efficiency was investigated at 45,65, and 85°C. For the SC−CO2 experiments, extraction efficiencies were proportional to pressure and inversely proportional to temperature, and the maximal
yield of oil achieved using SC−CO2 was 0.222±0.013 kg of oil extracted per kg of rice bran for conditions of 45°C and 35 MPa. The maximal yield achieved with
propane was 0.224±0.016 kg of oil per kg of rice bran at 0.76 MPa and ambient temperature. The maximum extraction efficiencies
of both SC−CO2 and propane were found to be significantly different from the hexane extraction baseline yield, which was 0.261±0.005 kg
oil extracted per kg of rice bran. A simulated economic analysis was performed on the possibility of using SC−CO2 and propane extraction technologies to remove oil from rice bran generated in Mississippi. Although the economic analysis
was based on the maximal extraction efficiency for each technology, neither process resulted in a positive rate of return
on investment. 相似文献
64.
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
65.
66.
The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses,i.e. coarse original rice husk ash (RHA0),RHA1,RHA2,and RHA3 were used for the study. Ordinary Portland cement (OPC) was partially replaced with rice husk ash at 20% by weight of binder. The water to binder ratio (W/B) of the mortar was maintained at 110%±5% with flow table test. Specific gravity,fineness,chemical properties,compressive strength,and porosity test of mor... 相似文献
67.
结合各生育期水稻耐盐度、各处理实际种前初始土壤含盐量和对应生育期最高的土壤含盐量,分析了各灌溉处理条件下的稻田土壤含盐量在水稻各生育期的动态变化规律和允许初始土壤含盐量阈值.结果表明:控制灌溉及控制灌溉加淋洗条件下,各水稻生育期土壤含盐量均有不同程度降低,随着淋洗水量的增加土壤含盐量逐渐降低,并获得了不同灌溉方式下的允许稻田初始土壤含盐量阈值.此结论对实际应用有指导意义. 相似文献
68.
糙米储藏品质评价数学模型的建立 总被引:1,自引:0,他引:1
为对糙米储藏过程中的劣变进行及时调控,选用2个粳糙米样品,测定不同储藏条件下的脂肪酸值、发芽率、生活力、电导率、降落数值等生理生化指标,进行各指标间的相关性分析,采用灰色关联度分析法对各项指标进行储藏品质敏感指标的筛选,并以各项敏感指标为自变量,以碾磨后的大米食味值为因变量,采用逐步回归的方法建立敏感指标与糙米最终食味值间的数学模型.结果表明:脂肪酸值、电导率对粳糙米储藏品质有显著影响,其中脂肪酸值对储藏品质敏感度最大,电导率次之;辽星糙米储藏品质评价的数学模型为y =92.57 +0.83X脂肪酸值-2.08X电导率,盐丰糙米储藏品质评价的数学模型为Y=-99.42+4.03X脂肪酸值-1.44X电导率. 相似文献
69.
丛枝菌根(AM)对水稻生长促进及化肥减量研究 总被引:5,自引:2,他引:3
为了考察丛枝菌根(Arbuscular Mycorrhiza,AM)对水稻生长促进及化肥减量效果,以摩西球囊霉(Glomus mosseae)为实验材料在不同丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)含量的基质中进行水稻盆栽试验.对比分析了水稻根部AMF的侵染状况,及其对水稻生长的促进作用,并在此基础上探讨了AMF强化在农业面源污染化肥减量中的作用.结果表明:自然基质中土著G.mosseae普遍存在,并可与水稻根系形成菌根结构,但其对水稻的影响与AMF空白基质相比差异并不显著.AMF强化能显著提高其对水稻根部的侵染率.与自然基质相比,AMF强化使水稻的株高、总生物量、根系总表面积及产量分别提高了20.6%、30%、36.6%、45.3%.经计算,每生产100kg水稻,AMF强化相对于自然条件下氮肥、磷肥、钾肥施用量分别减少3.14kg、1.88kg、2.42kg,削减程度高达47%.AMF强化能够有效促进水稻生长并提高其产量,而且在农业面源污染化肥减量方面具有重要作用. 相似文献
70.