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81.
以广西某静脉产业园内餐厨垃圾处理厂为例,介绍了以"预处理+油脂提取+厌氧发酵+沼气净化利用"为主体的餐厨垃圾处理工艺,并对该厂与生活垃圾焚烧厂协同处理进行了经济性分析。结果表明,与餐厨厂独立运营相比,与焚烧厂协同处理年节省成本达94.83万元。 相似文献
82.
为提高差分隐私保护下推荐算法的准确性,提出了一种考虑差分隐私保护的基于Bhattacharyya系数(BC)的聚类推荐算法.以BC作为项目相似性度量的标准,根据BC相似性对项目进行K-medoids聚类,并在聚类簇中进行私有项目邻居选择.最后,根据最近邻居集信息,对用户的评分进行预测和Top-n推荐.提出的方案有效地克服了已有方法中存在的相似性度量依赖于共同评分的问题,提高了相似性度量的准确性,有效避免了因隐私保护而造成的最近邻居集质量下降的问题.理论分析和实验测试的结果表明,该方法在实现隐私保护的同时还能有效保证推荐的高质量,较好地实现了隐私保护和数据效用之间的平衡,具有良好的应用潜力. 相似文献
83.
针对餐厨垃圾厌氧处理所产生的沼渣具有产量大、灰分质量分数高的特点,研究沼渣中无机灰分对其热解过程的影响. 通过热重分析和热裂解?气相色谱质谱联用技术(Py-GC/MS)分析沼渣热解动力学特性及其产物. 动力学分析结果表明,沼渣除灰后,失重速率显著提高,热解起始温度由180 ℃降至160 ℃. 除灰沼渣的总表观活化能比沼渣的略高,原因可能是除灰使沼渣内部孔隙增加,在促进挥发分析出的同时,削弱了部分组分在热解过程中的催化裂解作用. 产物分析结果表明,NaCl能够促进油相产物中烃类向酮类的转化,ZnCl2通过促进酸类的脱羧作用,使烃类质量分数提高至66.8%;Fe2O3和Al2O3使烃类物质的质量分数分别提高至66.8%和72.7%,CaO和MgO可以促进酸类脱羧生成酮,使产物中酮类的质量分数高达46.5%和39.4%. 相似文献
84.
智能温度控制仪在铝电解铸造保温炉上的应用 总被引:1,自引:0,他引:1
简要介绍了KX-C智能温控仪的性能、特点;结合铝电解铸造保温炉的控制要求,阐述了KX-C智能温控仪对保温炉的恒温控制过程。应用表明,该仪器由于具有控制准确、动作灵敏、接线简单、无需校准、成本较低、可靠性高、无需维护等优点,可很好满足实际生产的要求。 相似文献
85.
RFID生猪管理解决方案 总被引:1,自引:0,他引:1
提出了一种牲畜管理的自动化解决方案,它将现代化养殖技术和先进的科学技术手段结合在一起,为生猪的养殖和管理提供了新的管理方法,以提高生产效率. 相似文献
86.
Pengcheng Nie Fangfang Qu Lei Lin Yong He Xuping Feng Liang Yang Huaqi Gao Lihua Zhao Lingxia Huang 《International journal of molecular sciences》2021,22(7)
Molecular spectroscopy has been widely used to identify pesticides. The main limitation of this approach is the difficulty of identifying pesticides with similar molecular structures. When these pesticide residues are in trace and mixed states in plants, it poses great challenges for practical identification. This study proposed a state-of-the-art method for the rapid identification of trace (10 mg·L−1) and multiple similar benzimidazole pesticide residues on the surface of Toona sinensis leaves, mainly including benzoyl (BNL), carbendazim (BCM), thiabendazole (TBZ), and their mixtures. The new method combines high-throughput terahertz (THz) imaging technology with a deep learning framework. To further improve the model reliability beyond the THz fingerprint peaks (BNL: 0.70, 1.07, 2.20 THz; BCM: 1.16, 1.35, 2.32 THz; TBZ: 0.92, 1.24, 1.66, 1.95, 2.58 THz), we extracted the absorption spectra in frequencies of 0.2–2.2 THz from images as the input to the deep convolution neural network (DCNN). Compared with fuzzy Sammon clustering and four back-propagation neural network (BPNN) models (TrainCGB, TrainCGF, TrainCGP, and TrainRP), DCNN achieved the highest prediction accuracies of 100%, 94.51%, 96.26%, 94.64%, 98.81%, 94.90%, 96.17%, and 96.99% for the control check group, BNL, BCM, TBZ, BNL + BCM, BNL + TBZ, BCM + TBZ, and BNL + BCM + TBZ, respectively. Taking advantage of THz imaging and DCNN, the image visualization of pesticide distribution and residue types on leaves was realized simultaneously. The results demonstrated that THz imaging and deep learning can be potentially adopted for rapid-sensing detection of trace multi-residues on leaf surfaces, which is of great significance for agriculture and food safety. 相似文献
87.
Roxane Detry Vera Van Hoed Jérôme Sterckx Catherine Deledicque Kiyotaka Sato Christophe Blecker Sabine Danthine 《European Journal of Lipid Science and Technology》2021,123(1):2000155
Developing trans-free alternative fat solutions suitable for specific applications remains a challenge in edible fats and other domains. This is particularly true for palm oil-based puff pastry margarines, which suffer from post crystallization problems, leading to dramatic loss of functionality. This research is aimed at investigating the influence of triacylglycerol (TAG) compositions of palm oil-based puff pastry margarines on the physical properties of the fat crystal network, which determine the functionality of such products. Three model puff pastry margarines are produced at pilot scale under the same crystallization conditions. They share the same fatty acid composition and close solid fat content (SFC) profiles, whereas the proportions of major TAG (tripalmitoylglycerol (PPP), 1,3-di-palmitoyl-2-oleoylglycerol (POP), 1,2-di-palmitoyl-3-oleoylglycerol (PPO), 1,2-dioleoyl-3-palmitoylglycerol (POO)) are different. Polymorphism, melting profile, hardness, microscopic structures, and baking performance (puffing effect) of the model fats are examined during a period of 6 months. The following results are obtained: 1) The TAG composition significantly influences the post crystallization processes occurring in palm oil-based margarines. 2) High amounts of POP show negative influences. 3) The proportions of POP, PPO, and PPP should be carefully balanced to prevent detrimental crystal network rearrangements, leading to textural modifications (hardness increase) and significant reduction in baking performance. Practical Applications : The results presented in this work could be helpful for edible fat products developers, especially for roll-in fat applications. This research provides an overview of the relevant properties to study for the assessment of puff pastry margarine functionality. It also highlights the importance of ensuring long-term stability of palm oil-based fat products. Finally, it emphasizes that certain combinations of fat materials should be avoided to maintain the quality of palm oil-based puff pastry margarines. 相似文献
88.
89.
Dorota Johansson Björn Bergenståhl 《Journal of the American Oil Chemists' Society》1992,69(8):728-733
The influence of water on the interactions between fat and sugar crystals dispersed in triglyceride (vegetable) oils was qualitatively
estimated from sedimentation and rheological experiments. The experiments were performed both with and without food emulsifiers
(monoglycerides and lecithins) present in the oil. The effects of minor natural oil components (nontriglycerides) on the interactions
and on emulsifier adsorption to the crystals were examined by comparing a commercial refined oil and a chromatographically
purified oil. The results show that water generally increases the adhesion between fat and sugar crystals in oils and also
increases the surface activity of the oil-soluble food emulsifiers. Minor oil components give a small increase in the adhesion
between fat and sugar crystals in oils, but do not influence the adsorption of food emulsifiers in any systematic way. 相似文献
90.
用可以同时吸氧气与二氧化碳的双吸剂和挥发性抑菌剂富马酸单甲酯(MMF)复合成新型食品保鲜剂,能抑制30多种常见的霉菌等生物的生长,以可抗氧化变质和二氧化碳的影响。可用于粮食、蔬菜水果、干果、药物等的保质储存,改善了单纯双吸剂的保鲜性能,延长了食品的保鲜期。 相似文献