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991.
在中国房地产快速发展背景下,“城市住宅设计”教学中容易出现重点不清,以及学生对设计素材抄袭的问题。文章针对以住宅设计原理的掌握为主的教学要求,进行了“基于问题驱动的城市住宅课程设计”的实践探索。力图通过一条“问题驱动”的设计链条,引导问题的“发现”,控制问题的 “转化”,帮助学生结合设计条件对城市住宅进行主动的思考以及有目的的设计,以促成教学目标的达成。这样的教学方法有利于学生实现设计创新,并能够开拓具有社会角度的专业视野。  相似文献   
992.
介绍新疆地区微灌中常用过滤器的工作原理与特点,简述了过滤器与自动控制和自动冲洗的结合以及多种过滤器的联合使用。针对过滤器的发展趋势以及发展中面临的堵塞问题,指出了过滤器研究的几个方向。对于新疆农业的发展,微灌技术的发展、推广、应用、普及,以及过滤器的研究发展具有一定程度的积极作用。  相似文献   
993.
通过对邯钢高炉常用的6种喷吹煤种分别进行了可磨性、着火温度、爆炸性、工业分析和发热值等试验研究,对比分析了各煤种的性能,评价出无烟煤和烟煤的最优原料,为生产选择适宜的混喷煤种提供数据支持。  相似文献   
994.
铁路的建设与发展在中国近代史中占据着极其重要的地位,火车站房建筑也随之成为近代中国的重要公共建筑类型之一。本文的研究对象——天津西站,不仅因其独特的建设背景在当时呈现出别具一格的建筑风采,其中西融合、复杂多样的建筑设计语言更使其在百年之后仍以饱含文化韵味的建筑姿态吸引众多学者去探索、研究。文章从西站的建设背景——津浦铁路入手,通过整理分析史实资料,梳理其历史发展脉络,同时结合19世纪末20世纪初的欧洲建筑变革情况,对天津西站主楼的平立面、建筑细部设计、建筑风格、社会影响进行解析。  相似文献   
995.
Eukaryotic translation initiation factors are the principal molecular effectors regulating the process converting nucleic acid to functional protein. Commonly referred to as eIFs (eukaryotic initiation factors), this suite of proteins is comprised of at least 25 individual subunits that function in a coordinated, regulated, manner during mRNA translation. Multiple facets of eIF regulation have yet to be elucidated; however, many of the necessary protein factors are phosphorylated. Herein, we have isolated, identified and quantified phosphosites from eIF2, eIF3, and eIF4G generated from log phase grown HeLa cell lysates. Our investigation is the first study to globally quantify eIF phosphosites and illustrates differences in abundance of phosphorylation between the residues of each factor. Thus, identification of those phosphosites that exhibit either high or low levels of phosphorylation under log phase growing conditions may aid researchers to concentrate their investigative efforts to specific phosphosites that potentially harbor important regulatory mechanisms germane to mRNA translation.  相似文献   
996.
陈佳 《山西建筑》2012,38(29):104-106
以某水电站为实例,结合数值模拟,研究了河谷下切过程中断层、错动带以及侧向剥蚀对地应力的影响情况分析,为坝址区地应力特征研究提供了科学依据。通过计算得出:在断层、断层与断层及断层与层间错动带交错部位岩体应力明显减小,而侧向剥蚀主要影响左岸应力分布,对右岸应力分布的影响不是很明显。  相似文献   
997.
In this paper, we propose an approach of inferring the labels of unlabeled consumer videos and at the same time recognizing the key segments of the videos by learning from Web image sets for video annotation. The key segments of the videos are automatically recognized by transferring the knowledge learned from related Web image sets to the videos. We introduce an adaptive latent structural SVM method to adapt the pre-learned classifiers using Web image sets to an optimal target classifier, where the locations of the key segments are modeled as latent variables because the ground-truth of key segments are not available. We utilize a limited number of labeled videos and abundant labeled Web images for training annotation models, which significantly alleviates the time-consuming and labor-expensive collection of a large number of labeled training videos. Experiment on the two challenge datasets Columbia’s Consumer Video (CCV) and TRECVID 2014 Multimedia Event Detection (MED2014) shows our method performs better than state-of-art methods.  相似文献   
998.
This work is focused on the complementary information obtained from advanced in situ Fourier transform infrared (FTIR) spectroscopy and rheological measurements to correlate the structural changes with rheological properties upon polymerization of different organically modified montmorillonite clay/vinyl ester composites prepared by in situ polymerization. The microstructure and morphology of the nanocomposites were examined by X‐ray diffraction and transmission electron microscopy. The effect exerted by the presence of organic clay on the polymerization reaction of a vinyl ester based polymer matrix was evaluated. In situ and ex situ rheo‐FTIR measurements were compared to demonstrate the accuracy of this technique. © 2013 Society of Chemical Industry  相似文献   
999.
The characteristics of transverse relaxation time (T2) of water in wheat were studied by measuring the relaxation time of low-field nuclear magnetic resonance. Analysis of the exponential distribution of T2 revealed that wheat contains five water components. The T2 relaxation time and distribution significantly changed during drying. The dynamic characteristics of five water components during wheat drying were determined using the signal quantity of their characteristic peaks, which showed different features. Weakly chemically bound water (T22) and water ascribed to cell wall (T23) were the main source of water loss. Moreover, most T23 and extracellular water (T24) were removed during drying. Water migration between strongly chemically bound water (T21) and the other water components was bidirectional. This process was not only affected by temperature but also by wheat moisture content and proportion of the five water components. The start time of water migration advanced and growth rate of T21 at the end of drying to that before drying increased at 60, 70, and 80°C. Drying at varied temperatures should be applied according to the characteristics of five water components during the drying process. In addition, high initial temperature was found to be necessary to achieve high drying rate of T23, T24, and free water (T25). The use of drying temperature of 80°C at the early stage and then changing to 70°C reduced the heat consumption by 4.81% and increased the drying time by 9.61%.  相似文献   
1000.
This study explored the stability and degradation products of aloin A under varying pH, temperature and light conditions usually encountered in processing. The stability of aloin A was significantly affected by temperature and pH. The content of aloin A decreased by more than 90% within 12 h at 50 °C and within 6 h at 70 °C, respectively. A significant decrease in stability was also observed at higher pHs. At pH 8.0, less than 2% of aloin A remained within 12 h. However, aloin A exhibited good stability at acidic pH levels with 94% remaining at pH 2.0 for 14 days. Light exerted no influence on the stability during the experimental period (14 days). Aloe‐emodin, elgonica‐dimers A and B were characterised as major degradation products of aloin A at pH 5.0 or below, and elgonica‐dimers were mainly formed at 4 °C as well. 10‐hydroxyaloins A and B were found under any condition except at pH 2.0 and 3.0, and they were mainly formed under high temperature, neutral‐basic and any light conditions.  相似文献   
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