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991.
992.
《Journal of dairy science》2019,102(7):6235-6241
The purpose of this study was to optimize the conditions of a previously proposed enzymatic method used to estimate in situ undigested neutral detergent fiber (uNDF). We used a multi-step enzymatic approach, in which samples were first solubilized in NaOH solutions as a preincubation (PreInc) phase. After rinsing, samples were incubated (24 h at 39°C) in a buffered solution (pH 6) containing hemicellulase, cellulase, and Viscozyme L enzymes (Sigma-Aldrich s.r.l., Milan, Italy), followed by incubation (24 h at 39°C) in a buffered solution (pH 5) containing xylanase. Two sets of experiments were performed: a calibration trial (that tested different PreInc conditions on 9 selected forages) and a validation trial (that verified the results by testing multiple samples of 6 different forage types and a group of fibrous by-products). In the calibration trial, samples (300 mg in Ankom F57 filter bags; Ankom Technology Corp., Fairport, NY) were preincubated at 39°C in a 0.1 M NaOH solution for 90, 180, or 240 min, or in 0.2, 0.5, 1.0, or 2.0 M NaOH solution for 90 min. The results indicated that the best PreInc method, in terms of intra-laboratory repeatability and estimation of reference in situ values, was 90 min in a 0.2 M NaOH solution. Thus, we used this PreInc condition to determine enzymatic uNDF of 257 samples in the validation trial. Although the selected method generally had good accuracy in predicting in situ uNDF, inconsistencies were noted for certain forage types. Overall, when enzymatic uNDF was used to predict the in situ uNDF of all samples, the regression was satisfactory (intercept = 7.098, slope = 0.920, R2 = 0.73). The regression models developed for alfalfa hays, corn silages, and small grain silages had also acceptable regression performances and mean square error of prediction (MSEP) values, and the main sources of MSEP variation were error due to incomplete (co)variation and random error. Even when R2 values were >0.70, the MSEP value of the regression model for grass hays was 149.55, and that for nonforage fibrous feeds was 155.16. Although enzymatic uNDF partially overestimated the in situ uNDF, particularly in grass silages, the proposed procedure seems to be promising for accurately predicting in situ uNDF, because it generally had good repeatability and provided satisfactory estimates of in situ uNDF. 相似文献
993.
Patent mapping is an important method for analyzing technological patterns both for scientific research and strategic tasks in companies. In this paper we focus on a specific type of technological pattern, namely the analysis of patents' positions in relation to predefined positions of application fields. For this purpose we use an anchoring approach. We apply semantic patent measurement and discuss RadViz as a powerful method to visualize the measurement's results and to provide insightful motion patterns for monitoring technology change. Moreover, we present an algorithm to define so called anchor points as high dimensional reference points by using textual elements of patents. By the example of carbon fiber reinforcements we demonstrate the usefulness of our approach. Thus, our approach enables academics to analyze important types of technological patterns like convergence or divergence by means of a new instrument and gives practitioners like the R&D management of companies the opportunity to build a reliable strategic business decision support. 相似文献
994.
Long Fan 《Chemical Engineering Communications》2016,203(9):1139-1144
Fiber particles have some unique behaviors due to their special shapes, which are important to those related industries. When a single fiber is in a particle cloud, its behavior will be influenced by others around it. Hence, the behavior of an isolated fiber particle will be different from that in a particle cloud, such as aggregation, orientation, and drag coefficient. However, little information is available on these phenomena, especially drag coefficient. Therefore, this article focuses on the settling process of a fiber particle in a particle cloud. Experiments were conducted to observe the settling behavior of fiber particles and to determine the drag coefficients of an isolated fiber particle in a particle cloud. The relationship between drag coefficient, orientation, and Re for different fiber particles is obtained, which is independent of volume concentration. It is further observed that the aspect ratio has little influence on the drag coefficients of fiber particles. By comparison, it is noticed that these relationships are similar to those found for an isolated single-fiber particle. Furthermore, the orientation of a fiber particle in a particle cloud fluctuates around the stable horizontal orientation in the same way as a single-fiber particle, but returns to the steady state more quickly. 相似文献
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997.
In this paper,the waveforms in time domain and frequency domain of two kinds of optical frequency domain reflectometry (OFDR) sensing systems are compared,which use common fiber Bragg grating (FBG) and... 相似文献
998.
由于下游过滤器和喷丝板的制约,纤维素溶解器需要用低黏度混合物操作一直制约着纤维素纺丝原液的质量和通过量。瑞士List公司开发了MasterConti工艺,消除了溶解工艺和下游工艺相互间的影响,从而克服了上述制约。该工艺已通过试验验证,现能用于新装置,也可用于扩大现有装置的产能。 相似文献
999.
Biochar is widely recognized as an effective material for sequestration of carbon dioxide. The possibility of using it as a coating material on polypropylene fibers to improve mechanical properties and permeability mortar is explored in this study. Effectiveness of two types of biochar – fresh biochar and biochar saturated with carbon dioxide prior to application as coating – on compressive and flexural strength, post-cracking behavior and permeability of mortar is studied. The biochar used was derived from mixed wood saw dust by pyrolysis at 300 °C. Experimental results show that application of fresh biochar coating offer significant improvement in compressive strength and flexural strength of mortar. Residual strength and post-cracking ductility of mortar with biochar coated fibers is found to be higher than control samples, although fresh biochar coating offers the best performance. Mortar with polypropylene fibers coated with fresh biochar shows higher impermeability, compared to reference samples and mortar with saturated biochar coated fibers. The findings suggest that biochar coating could be a potential solution to improve properties of fiber reinforced cementitious composites that also promotes waste recycling and carbon sequestration. 相似文献
1000.
高温耐火纤维整体拼装作为一种先进的材料和技术,在轧钢加热炉炉顶上运用比传统的耐火材料炉顶有着显著的优点,能大幅度延长炉顶的使用寿命,减少加热炉的热损失,缩短加热炉炉顶的检修时间,提高炉子生产率。 相似文献