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101.
Søren Debois 《Higher-Order and Symbolic Computation》2008,21(1-2):37-58
We describe how to implement strength reduction, loop-invariant code motion and loop quasi-invariant code motion by specializing instrumented interpreters. To curb code duplication intrinsic to such specialization, we introduce a new program transformation, rewinding, which uses Moore-automata minimization to remove duplicated code. 相似文献
102.
Almost all analyses of large structures neglect local effects due to the application of loads and due to the transfer of loads between structural elements. In recent years, however, the use in aircraft structures of highly anisotropic materials, such as graphite/epoxy, has motivated more detailed studies of the applicability of Saint-Venant's principle.
In this paper in graphite/epoxy is analysed using the finite element method (FEM). The influence of anisotropy and transition from a thicker to a thinner laminate cross-section (ply-drop) is investigated. The characteristic decay length which is large for highly anisotropic materials is lessened by a change in thickness. 相似文献
103.
Mnica Mendes Fbris Kossoski Ana I. Lozano Joo Pereira-da-Silva Rodrigo Rodrigues Joo Ameixa Nykola C. Jones Sren V. Hoffmann Filipe Ferreira da Silva 《International journal of molecular sciences》2021,22(12)
We report absolute photoabsorption cross sections for gas-phase 2- and 5-bromopyrimidine in the 3.7–10.8 eV energy range, in a joint theoretical and experimental study. The measurements were carried out using high-resolution vacuum ultraviolet synchrotron radiation, with quantum chemical calculations performed through the nuclear ensemble approach in combination with time-dependent density functional theory, along with additional Franck–Condon Herzberg–Teller calculations for the first absorption band (3.7–4.6 eV). The cross sections of both bromopyrimidines are very similar below 7.3 eV, deviating more substantially from each other at higher energies. In the 7.3–9.0 eV range where the maximum cross-section is found, a single and broad band is observed for 5-bromopyrimidine, while more discernible features appear in the case of 2-bromopyrimidine. Several π* ← π transitions account for the most intense bands, while weaker ones are assigned to transitions involving the nitrogen and bromine lone pairs, the antibonding σ*Br orbital, and the lower-lying Rydberg states. A detailed comparison with the available photo-absorption data of bromobenzene is also reported. We have found significant differences regarding the main absorption band, which is more peaked in bromobenzene, becoming broader and shifting to higher energies in both bromopyrimidines. In addition, there is a significant suppression of vibrational structures and of Rydberg states in the pair of isomers, most noticeably for 2-bromopyrimidine. 相似文献
104.
风洞边壁对挟沙气流流速分布的影响 总被引:3,自引:0,他引:3
鉴于现有挟沙气流流速分布研究中对风洞边壁影响的认识不足,本文通过改变风洞宽度的方法对风洞边壁的影响进行了探索性实验研究。在五种宽高比条件下,对风洞断面挟沙气流流速分布进行了测量。发现风洞边壁对挟沙气流流速分布有较为明显的影响。在风洞宽度比相同的条件下,断面内中垂线上的有效粗糙度系数大于其它垂线上对应的系数。从靠近边壁的垂线到断面中垂线,各垂线对应的跃移层内区及外区流速分布的上界高度、气流摩阻速度均逐渐增大。随着风洞宽高比的减小,断面内中垂直线上的气流摩阻速度与自由流速的比值以及受风洞边壁影响的气流厚度均增大。 相似文献
105.
Biogenic amine content of boza: A traditional cereal-based, fermented Turkish beverage 总被引:4,自引:0,他引:4
Boza is a fermented beverage made from millet, maize, wheat or rice. Biogenic amine contents of 10 boza samples from different manufacturers in Turkey were analysed for the first time, using HPLC after derivatisation with benzoyl chloride. Of the 11 biogenic amines under study, putrescine, spermidine and tyramine were detected in all boza samples. Tyramine was the prevailing biogenic amine. Tyramine concentrations of boza samples were between 13 and 65 mg/kg. Total biogenic amine contents of boza samples were between 25 and 69 mg/kg. Consequently, consumption of boza might represent a health risk for patients being treated with drugs containing monoamine oxidase inhibitor (MAOI). The pH values of boza samples were in the range from 3.16 to 4.02; total dry matters were from 15.3% to 31.1% (w/w); protein contents were from 0.50% to 0.99% (w/w). No significant correlations were detected between biogenic amine concentrations and pH, protein content and total dry matter content. 相似文献
106.
107.
介绍了根据霍夫曼乳液过滤器工作原理制作的热粗轧机乳液真空过滤器的过滤原理及其应用。 相似文献
108.
采用镁、钙和锌的氢氧化合物分别与辛酰丙氨酸配体[CH3(CH2)6CONHCH(CH3)COOH]反应,合成了辛酰丙氨酸镁、钙和锌表面活性剂配合物。通过配合物的纯溶媒及水/有机溶媒系的溶解性测试发现,镁和钙的配合物均在大部分有机纯溶媒和水/有机溶媒系里有极高的溶解性,而锌的配合物在大部分有机纯溶媒系里有很低的溶解性。此外,通过核磁共振(NMR)光谱、电导、蒸汽压降下(VPO)和FTIR方法研究了溶液中镁、钙和锌表面活性剂配合物的聚集行为。Mg(oct-ala)2、Ca(oct-ala)2和Zn(oct-ala)2配合物在有机溶媒系里吸附水易发生聚集行为,并有形成逆胶束体的倾向。 相似文献
109.
Ekrem Köksal Ercan Bursal İlhami Gülçin Mustafa Korkmaz Cüneyit Çağlayan Ahmet C. Gören 《International Journal of Food Properties》2017,20(3):514-525
Like tea, the leaves of Turkish thyme (Thymus vulgaris) can be boiled in water to produce an extract. This is widely used as syrup for the treatment of coughs and bronchitis at alternative medicine clinics in many parts of the world. In the current study, we assessed the phenolic content and antioxidant activity of thyme. The antioxidant activities of both ethanol and aqueous extracts of thyme were determined using various in vitro methods. The total phenolic and total flavonoid contents were determined to be a gallic acid equivalent and a quercetin equivalent, respectively. Finally, the quantities of the phenolic compounds were detected using high-performance liquid chromatography and tandem mass spectrometry. The total phenolic compounds in the aqueous extract and ethanol extracts of Turkish thyme were 256.0 μg gallic acid equivalent/mg dried extract and 158.0 μg gallic acid equivalent/mg dried extract, respectively. Conversely, the total flavonoid compounds in both extracts were 44.2 μg and 36.6 μg quercetin equivalent/mg dried extract, respectively. For the first time, we determined phenolic contents and investigated the antioxidant potential of thyme. The results indicate that Turkish thyme is a good dietary source with phenolic properties. 相似文献
110.
按双液相溶剂并流浸出破碎油菜籽的方式,建立了浸出器理论级计算模型。模型关联了各股物料相对流率、油脂在各流股的相平衡参数,考虑了菜籽粕对两相溶剂的夹带返混作用,计及了浸取级效率。该模型可用于求取满足一定浸出要求所需浸出器的理论级数,或用于求取正在使用浸出器的两相溶剂的返混程度和平均级效率。模型计算结果与串级实验测定结果吻合较好,串级实验的级效率在0.32—0.54之间。模型计算结果表明,甲醇相溶剂比(L/kg)的大小和菜籽粕夹带甲醇量的多少对油浸取级数影响不大,但已烷相溶剂比(L/kg)的大小和菜籽粕夹带己烷量的多少对油浸取级数影响明显。该理论级计算模型可用于浸出过程的设计,可为实际生产提供参考数据。 相似文献