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61.
Dihydropyrimidine‐based compounds belong to the first discovered inhibitors of the human mitotic kinesin Eg5. Although they are used by many research groups as model compounds for chemical genetics, considerably less emphasis has been placed on the improvement of this type of inhibitor, with the exception of two recent studies. Dihydropyrimidines can be divided into class I (analogues that bind in the S configuration) and class II type inhibitors, which bind in the R configuration. Herein we report the synthesis and optimization of novel class II type dihydropyrimidines using a combination of in vitro and docking techniques.  相似文献   
62.
In recent years, neural networks have turned out as a powerful method for numerous practical applications in a wide variety of disciplines. In more practical terms neural networks are one of nonlinear statistical data modeling tools. They can be used to model complex relationships between inputs and outputs or to find patterns in data. In food technology artificial neural networks (ANNs) are useful for food safety and quality analyses, predicting chemical, functional and sensory properties of various food products during processing and distribution. In wine technology, ANNs have been used for classification and for predicting wine process conditions. This review discusses the basic ANNs technology and its possible applications in wine technology.  相似文献   
63.
Reference trajectory generation plays a key role in the computer control of machine tools. Generated trajectories must not only describe the desired tool path accurately, but must also have smooth kinematic profiles in order to maintain high tracking accuracy, and avoid exciting the natural modes of the mechanical structure or servo control system. Spline trajectory generation techniques have become widely adopted in machining aerospace parts, dies, and molds for this reason; they provide a more continuous feed motion compared to multiple linear or circular segments and result in shorter machining time, as well as better surface geometry. This paper presents a quintic spline trajectory generation algorithm that produces continuous position, velocity, and acceleration profiles. The spline interpolation is realized with a novel approach that eliminates feedrate fluctuations due to parametrization errors. Smooth accelerations and decelerations are obtained by imposing limits on the first and second time derivatives of feedrate, resulting in trapezoidal acceleration profiles along the toolpath. Finally, the reference trajectory generated with varying interpolation period is re-sampled at the servo loop closure period using fifth order polynomials, which enable the original kinematic profiles to be preserved. The proposed trajectory generation algorithm has been tested in machining a wing surface on a three axis milling machine, controlled with an in house developed open architecture CNC.  相似文献   
64.
Salep samples obtained from 10 different Orchidaceae spp., namely Dactylorhiza osmanica var. osmanica, Ophrys mammosa, Orchis anatolica, Orchis coriophora, Orchis italica, Orchis morio, Orchis palustris, Orchis simia, Orchis tridentata and Serapias vomeracea ssp. orientalis, in Anatolia, were analyzed for moisture, glucomannan, starch, protein, ash contents, pH and viscosity values. Depending on the species, the samples showed statistically significant differences in glucomannan, starch and viscosity values. It was observed that the salep samples obtained from the tubers of O. italica, O. morio, O. anatolica and O. tridentata and S. vomeracea ssp. orientalis, respectively, had higher glucomannan contents and viscosities. To ensure a supply of high-quality salep, the uncontrolled collection of tubers from the wild, especially the species O. italica, O. morio and O. anatolica, should be prevented, and research into methods of cultivation should be carried out.  相似文献   
65.
66.
In this study, immobilization of laccase (L) enzyme on magnetite (Fe3O4) nanoparticles was achieved, so that the immobilized enzyme could be used repeatedly. For this purpose, Fe3O4 nanoparticles were coated and functionalized with chitosan (CS) and laccase from Trametes versicolor was immobilized onto chitosan‐coated magnetic nanoparticles (Fe3O4‐CS) by adsorption or covalent binding after activating the hydroxyl groups of chitosan with carbodiimide (EDAC) or cyanuric chloride (CC). For chitosan‐coated magnetic nanoparticles, the thickness of CS layer was estimated as 1.0–4.8 nm by TEM, isoelectric point was detected as 6.86 by zeta (ζ)‐potential measurements, and the saturation magnetization was determined as 25.2 emu g?1 by VSM, indicating that these nanoparticles were almost superparamagnetic. For free laccase and immobilized laccase systems, the optimum pH, temperature, and kinetic parameters were investigated; and the change of the activity against repeated use of the immobilized systems were examined. The results indicated that all immobilized systems retained more than 71% of their initial activity at the end of 30 batch uses. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
67.
In this work, we make use of 3D contours and relations between them (namely, coplanarity, cocolority, distance and angle) for four different applications in the area of computer vision and vision-based robotics. Our multi-modal contour representation covers both geometric and appearance information. We show the potential of reasoning with global entities in the context of visual scene analysis for driver assistance, depth prediction, robotic grasping and grasp learning. We argue that, such 3D global reasoning processes complement widely-used 2D local approaches such as bag-of-features since 3D relations are invariant under camera transformations and 3D information can be directly linked to actions. We therefore stress the necessity of including both global and local features with different spatial dimensions within a representation. We also discuss the importance of an efficient use of the uncertainty associated with the features, relations, and their applicability in a given context.  相似文献   
68.
Kalkan  E.  Kunnath  S.K. 《钢结构》2008,(5)
基于设计的性能分析方法的一个关键部分是,对地震需求谱参数的准确采用。非线性静力方法(NSPs)现在广泛应用在工程实践上,主要用于预测房屋建筑的抗震能力。利用NSPs,地震需求谱可以从特定地点的危险性谱中直接计算出来,而非线性时程分析需要全部地面运动和针对地震记录可变性的相关性评估。除此之外,基于恒载模式(ATC-40和FEMA-356中所推荐的)NSP简化版本有条文说明其无法考虑由结构弹塑性而导致的更高模态效应以及模态变化。因此,研究者纷纷提出解决了以上缺点的改进Pushover法。通过对典型的钢结构和钢筋混凝土结构的突出反应特征与一套全面的NTH分析中得到的基准反应的比较,研究了多种非线性静力分析方法(NSPs)的有效性。更重要的是,考虑到多种地面运动特征,还采用了一组从普通的远断层记录到近断层地面运动的时间序列。这项分析研究的结果显示,较之该项研究中的其他非线性分析方法,适应性组合模型方法可以更为准确地预测如层间位移、塑性角等的极值。  相似文献   
69.
The aim of this study was to investigate the survival of Helicobacter pylori during production of sucuk (Turkish fermented sausage). The sucuk mixture was inoculated with H. pylori ATCC 43504 to produce a final level in the mixture of ~5 × 10(6) CFU/g. Samples in group I were fermented and dried traditionally at 22°C for 7 days. Samples in groups II and III were subjected to the traditional fermentation at 22°C for 3 days. After fermentation, group II samples were fermented and dried at 35°C for 4 days and group III samples were treated with heat until the core temperature reached 65°C. On the first day of fermentation, a 1-log reduction in H. pylori was found in all groups. The H. pylori levels in all groups increased by about 1 log CFU/g by the third day of fermentation and reached the inoculation level. On the fifth and seventh days of fermentation, no appreciable change occurred in the level of H. pylori in groups I and II. After heat treatment, the H. pylori levels were below the level of detection. These results suggest that H. pylori can grow during sucuk fermentation and that a heat treatment should be used during sucuk processing to destroy H. pylori.  相似文献   
70.
The aim of the study was to investigate the quality of blended wines produced from Vitis vinifera L. Cabernet Sauvignon, Merlot and Sauvignon blanc grapes. Wines were processed according to accepted conventional methods for white and red wines. Blended wines were produced with different ranges (25, 50, 75 and 100%) of Cabernet Sauvignon, Merlot and Sauvignon blanc wines. Produced wines were evaluated for total phenols (mg/L), total tartaric esters (mg/L caffeic acid), total flavonols (mg/L quercetin), chemometric parameters such as D280%, D420%, D520%, D620%, dA%, CD%, T, CI%, R%, Y% and B%, CIELAB parameters, protein, total and volatile acidity. Analyses on an n‐dimensional scale demonstrated the relationships among the wines of different grape origins and different blending ratios. On the basis of these differences, two main groups were plotted using principal component analysis and cluster analysis. The results demonstrate the possibilities of optimizing wines on the basis of defined parameters. Copyright © 2015 The Institute of Brewing & Distilling  相似文献   
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