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This paper reports on the development of a method for automatic monitoring of safety at Pelican crossings. Historically, safety monitoring has typically been carried out using accident data, though given the rarity of such events it is difficult to quickly detect change in accident risk at a particular site. An alternative indicator sometimes used is traffic conflicts, though this data can be time consuming and expensive to collect. The method developed in this paper uses vehicle speeds and decelerations collected using standard in situ loops and tubes, to determine conflicts using vehicle decelerations and to assess the possibility of automatic safety monitoring at Pelican crossings. Information on signal settings, driver crossing behaviour, pedestrian crossing behaviour and delays, and pedestrian-vehicle conflicts was collected synchronously through a combination of direct observation, video analysis, and analysis of output from tube and loop detectors. Models were developed to predict safety, i.e. pedestrian-vehicle conflicts using vehicle speeds and decelerations.  相似文献   
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Protein existence in wastewater is an important issue in wastewater management because proteins are generally present as contaminants and foulants. Hence, in this study, we focused on designing a polysulfone (PSf) hollow-fiber membrane embedded with hydrophilic iron oxide nanoparticles (IONPs) for protein purification by means of ultrafiltration. Before membrane fabrication, the dispersion stability of the IONPs was enhanced by the addition of a stabilizer, namely, citric acid (CA). Next, PSf–IONP–CA nanocomposite hollow-fiber membranes were prepared via a dry–wet spinning process and then characterized in terms of their hydrophilicity and morphology. Ultrafiltration and adsorption experiments were then conducted with bovine serum albumin as a model protein. The results that an IONP/CA weight ratio of 1:20 contributed to the most stable IONP dispersion. It was also revealed that the membrane incorporated with IONP–CA at a weight ratio of 1:20 exhibited the highest pure water permeability (58.6 L m−2 h−1 bar−1) and protein rejection (98.5%) while maintaining a low protein adsorption (3.3 μg/cm2). The addition of well-dispersed IONPs enhanced the separation features of the PSf hollow-fiber membrane for protein purification. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47502.  相似文献   
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The effect of process interaction and response surface optimization of hydrogen-rich syngas production by catalytic carbon dioxide (CO2) reforming of methane (CH4) was evaluated. The Box-Behnken design was applied to investigate the influence of CH4 partial pressure, CO2 partial pressure, and temperature on the hydrogen yield. The analysis of variance indicated that temperature and CH4 partial pressure had the most significant impact on the hydrogen yield. Under optimum conditions a maximum hydrogen yield of 71.38 % was achieved. Model validation with the ideal conditions confirmed close agreement of the predicted hydrogen yields with experimental values.  相似文献   
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Metallohydrolases form a large group of enzymes that have fundamental importance in a broad range of biological functions. Among them, the purple acid phosphatases (PAPs) have gained attention due to their crucial role in the acquisition and use of phosphate by plants and also as a promising target for novel treatments of bone-related disorders and cancer. To date, no crystal structure of a mammalian PAP with drug-like molecules bound near the active site is available. Herein, we used a fragment-based design approach using structures of a mammalian PAP in complex with the MaybridgeTM fragment CC063346, the amino acid L-glutamine and the buffer molecule HEPES, as well as various solvent molecules to guide the design of highly potent and efficient mammalian PAP inhibitors. These inhibitors have improved aqueous solubility when compared to the clinically most promising PAP inhibitors available to date. Furthermore, drug-like fragments bound in newly discovered binding sites mapped out additional scaffolds for further inhibitor discovery, as well as scaffolds for the design of inhibitors with novel modes of action.  相似文献   
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Multimedia Tools and Applications - Analysis of facial images decoding familial features has been attracting the attention of researchers to develop a computerized system interested in determining...  相似文献   
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Introduction: Inactivity, uremia, and malnutrition in dialysis patients may lead to decreased muscle mass and physical capacity. As a preventative measure, dialysis patients are provided with an intradialytic exercise program. Our study aimed to determine the role of intradialytic exercise performed 2 times per week on physical capacity, inflammation, and nutritional status in dialysis patients and to determine which exercises are more suitable for this population. Methods: A randomized clinical trial in which participants were randomly assigned to 1 of 3 groups, i.e., a group of patients performing aerobic exercise, a group of patients performing a combination of aerobic and resistance exercise and the control group. The study was conducted at the Dialysis Unit of Dr. Cipto Mangunkusumo General Hospital, Jakarta for 12 weeks from February to May 2018. The inclusion criteria were dialysis patients aged over 18 years who had undergone routine dialysis for over 3 months. Findings: A total of one hundred twenty patients were included in the study. There was a significant increase in lower extremity strength in the group performing aerobic exercise and in the combined exercise group compared to the lower extremity strength of the control group. There was also a significant increase in the physical component score (PCS) of the KDQOL‐SF? instrument in the aerobic training and combination exercise groups compared to the PCS of the control group. No significant differences were found between the combination exercise group and the aerobic training group in any outcome. Discussion: Both types of exercise programs significantly increased the lower extremity muscle strength and the PCS of the quality of life index. Combination exercise was not more effective than aerobic exercise for dialysis patients.  相似文献   
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Nano-Micro Letters - Antibacterial activity of zinc oxide nanoparticles (ZnO-NPs) has received significant interest worldwide particularly by the implementation of nanotechnology to synthesize...  相似文献   
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