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991.
Front Cover: Synthesis,Crystallization Studies,and in vitro Characterization of Cinnamic Acid Derivatives as SmHDAC8 Inhibitors for the Treatment of Schistosomiasis (ChemMedChem 15/2018) 下载免费PDF全文
Theresa Bayer Dr. Alokta Chakrabarti Dr. Julien Lancelot Dr. Tajith B. Shaik Kristin Hausmann Jelena Melesina Karin Schmidtkunz Dr. Martin Marek Dr. Frank Erdmann Dr. Matthias Schmidt Dr. Dina Robaa Dr. Christophe Romier Dr. Raymond J. Pierce Prof. Dr. Manfred Jung Prof. Dr. Wolfgang Sippl 《ChemMedChem》2018,13(15):1488-1488
992.
Based on experimental measurements of the in situ conditions within polymer flow during micro‐injection molding, a new geometrical parameter is defined to predict realistic dimensions of micro‐parts (μparts). To this aim, thin‐walled parts of various aspect ratios “length/thickness” (L/h) were first molded, with two different polymers: (i) a polystyrene and (ii) a cyclo‐olefin copolymer. It is shown that pressure drops (ΔPi), measured between the injection pressure and the various sensors present in the mold, are directly related to the square of the ratio of L/h. This approach has finally been successfully applied to the results of the literature, confirming its relevance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45719. 相似文献
993.
Performance evaluation of fixed‐bed,millistructured, and metallic foam reactor channels for CO2 methanation 下载免费PDF全文
994.
Thermomechanical characteristics of calcium aluminate cement and sand tapes prepared by tape casting
Julien Soro Agns Smith Christian Gault 《Journal of the European Ceramic Society》2006,26(16):3799-3807
The present paper concerns the mechanical characterization of calcium aluminate cement and sand tapes prepared by tape casting, including ultrasonic measurements of Young's modulus at high temperature and evaluation of four point flexural behavior after heat treatments in the range of 20–1400 °C. It is shown that dehydration strongly affects mechanical properties in the 400–900 °C range, but that treatments at temperatures higher than 1200 °C increase both Young's modulus and strength. By correlation with thermal and X-ray diffraction analyses, the evolutions of thermomechanical properties have been related to phase and microstructural changes when heating the material after hydration: conversion of hydrates and dehydration at low temperature, then, crystallization of C–A and C–A–S phases and finally sintering at the highest temperatures. In a last part, it is shown that the reinforcement by glass fibres enhances the mechanical properties, in particular in the temperature range of dehydration, and gives to the material a non-brittle behavior. 相似文献
995.
Object detection in a dynamic background is a challenging task in many computer vision applications. In some situations, the motion of objects can be predicted thanks to its regularity (e.g., vehicle motion, pedestrian motion). In this article, we propose to model such motion knowledge and to use it as additional information to help in foreground detection. The inclusion of object motion information provides a measure for distinguishing moving objects from a background that has similar sizes and brightness levels. This information is obtained by applying statistical methods on data obtained during the training period. When available, prior knowledge can be incorporated into the foreground detection process to improve robustness and to decrease false detection. We apply this framework to moving object detection in rivers, one of the situations in which classic background subtraction algorithms fail. Our experiments show that the incorporation of prior motion data into background subtraction improves object detection. 相似文献
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Cloud computing promises the delivery of on-demand pay-per-use access to unlimited resources. Using these resources requires more than a simple access to them as most clients have certain constraints in terms of cost and time that need to be fulfilled. Therefore certain scheduling heuristics have been devised to optimize the placement of client tasks on allocated virtual machines. The applications can be roughly divided in two categories: independent bag-of-tasks and workflows. In this paper we focus on the latter and investigate a less studied problem, i.e., the effect the virtual machine allocation policy has on the scheduling outcome. For this we look at how workflow structure, execution time, virtual machine instance type affect the efficiency of the provisioning method when cost and makespan are considered. To aid our study we devised a mathematical model for cost and makespan in case single or multiple instance types are used. While the model allows us to determine the boundaries for two of our extreme methods, the complexity of workflow applications calls for a more experimental approach to determine the general relation. For this purpose we considered synthetically generated workflows that cover a wide range of possible cases. Results have shown the need for probabilistic selection methods in case small and heterogeneous execution times are used, while for large homogeneous ones the best algorithm is clearly noticed. Several other conclusions regarding the efficiency of powerful instance types as compared to weaker ones, and of dynamic methods against static ones are also made. 相似文献
999.
Fracture strength assessment and aging signs detection in human cortical bone using an X-FEM multiple scale approach 总被引:1,自引:1,他引:0
We present a multiple scale approach for modeling multiple crack growth in human cortical bone under tension. The Haversian
microstructure, a four phase composite, is discretized by a classical finite element method fed with the morphological and
mechanical characteristics, experimentally measured, to mimic human bone heterogeneity at the micro scale. The fracture strength
of human bone, exhibiting aging signs, is investigated through tensional percolation simulations in statistical microstructures.
The cracks are initiated at the micro scale at locations where a critical elastic-damage strain-driven criterion is met. The
cracks, modeled by the eXtended Finite Element Method, are then grown until complete failure when a critical stress intensity
factor criterion is attained. The model provides the fracture strength and the global response at the material scale and the
stress–strain fields at the microscopic level. The model creates a constitutive law at the material scale and emphasizes the
influence of the microstructure on bone failure and fracture risk assessment. These results are validated against experiments. 相似文献
1000.
This paper presents a compact microelectrode array (MEA) system, to study potassium ion-induced dopamine release from PC12 neural cells, without relying on a micromanipulator and a microscope. The MEA chip was integrated with a custom-made "test jig", which provides a robust electrical interfacing tool between the microchip and the macroenvironment, together with a potentiostat and a microfluidic syringe pump. This integrated system significantly simplifies the operation procedures, enhances sensing performance, and reduces fabrication costs. The achieved detection limit for dopamine is 3.8 x 10-2 muM (signal/noise, S/N = 3) and the dopamine linear calibration range is up to 7.39 +/- 0.06 muM (mean +/- SE). The effects of the extracelluar matrix collagen coating of the microelectrodes on dopamine sensing behaviors, as well as the influences of K+ and l-3,4-digydroxyphenylalanine concentrations and incubation times on dopamine release, were extensively studied. The results show that our system is well suited for biologists to study chemical release from living cells as well as drug effects on secreting cells. The current system also shows a potential for further improvements toward a multichip array system for drug screening applications. 相似文献