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951.
Notwithstanding many years of progress, visual tracking is still a difficult but important problem. Since most top-performing tracking methods have their strengths and weaknesses and are suited for handling only a certain type of variation, one of the next challenges is to integrate all these methods and address the problem of long-term persistent tracking in ever-changing environments. Towards this goal, we consider visual tracking in a novel weakly supervised learning scenario where (possibly noisy) labels but no ground truth are provided by multiple imperfect oracles (i.e., different trackers). These trackers naturally have intrinsic diversity due to their different design strategies, and we propose a probabilistic method to simultaneously infer the most likely object position by considering the outputs of all trackers, and estimate the accuracy of each tracker. An online evaluation strategy of trackers and a heuristic training data selection scheme are adopted to make the inference more effective and efficient. Consequently, the proposed method can avoid the pitfalls of purely single tracking methods and get reliably labeled samples to incrementally update each tracker (if it is an appearance-adaptive tracker) to capture the appearance changes. Extensive experiments on challenging video sequences demonstrate the robustness and effectiveness of the proposed method.  相似文献   
952.
Industries will implement effective training programs to improve training performance, and an ideal training performance occurs under proper mental workload (MWL). Virtual reality (VR) has recently been widely utilized in training; however, only a few studies have investigated its effects on MWL and training performance simultaneously. The purpose of this study is to investigate the effects of VR training and traditional training methods, such as technical manuals (TM) and multimedia films (MF), on training performance and MWL. The results of the performance measurement show that VR training is considered the best training method compared to TM and MF, particularly in the case of complex tasks. The results of physiological measurements (GSR [galvanic skin response], LF% [low frequency], and LF/HF [high frequency] ratio) show a significant difference between reading TM and using computer (MF and VR), wherein the latter has a lower MWL. However, no significant difference in subjective MWL assessment (NASA‐TLX [task load index]) and HF% measurement is found.  相似文献   
953.
Polyglycolic acid (PGA) is a class of semicrystalline, bioresorbable polymers that have been widely used in a number of applications. No other bioresorbable materials can fully replace PGA in tissue engineering. Understanding degradation mechanisms in PGA is important for improving the efficiency and effectiveness in various fields including implantation. This review begins with a discussion on terminology of polymer degradation and hydrolytic degradation mechanism with a delineative model. This review also focus on previous degradation studies taking advantage of its fast-degrading behavior and the mechanism behind hexafluoroisopropanol (HFIP) being the sole solvent for PGA. Finally, the merits of PGA are discussed with many potential future applications along with their associated challenges.  相似文献   
954.
Food Science and Biotechnology - Betacyanins are bioactive dietary phytochemicals which can be found in red dragon fruit (RDF). Therefore, the bioaccessibility of betacyanins that present in...  相似文献   
955.

Emissions of natural gas and carbon dioxide due to fossil fuels have become a global issue which influences the development of various technologies. Demand for clean renewable power sources is ever increasing. However, renewable sources are intermittent in nature, which poses a challenge in electricity generation and power load stability. Lately, supercapacitors have attracted remarkable interest in the field of electricity storage due to their ability to store large amounts of electric charge, enabling high power output. Reduced graphene oxide incorporated with titanium dioxide (rGO/TiO2) nanocomposites are well considered as potential supercapattery materials due to their superior mechanical properties, notable strength, and abundance in Nature. rGO carbon material acts as the ion reservoir, facilitating faster electron transfer mobility, whereas mesoporous TiO2 provides a larger surface area and more active sites, which improve the cycling stability and specific capacitance. Literature reports that supercapacitor performance mainly depends on the choice of the electroactive material, electrolyte, and current collector. This review focuses on recent developments in supercapacitor technology, storage mechanisms of different electrodes, a comprehensive discussion of different challenges related to energy storage devices, as well as the formation mechanism of rGO/TiO2 hybrid electrodes.

  相似文献   
956.
Dietary fat has an important influence on mammalian lipid homeostasis. However, the relationship between dietary fat types and endogenous fatty acids (FAs) in organs as well as lipid homeostasis remains unclear enough. In this study, rats are randomly divided into a control group (CN), a high-colleseed oil group (COG), and a high-sunflower oil group (SOG). FAs profile in liver and visceral fats of rats in two high-fat (HF) diet groups is compared with that in CN. Oleic, γ-linolenic, eicosadienoic, and arachidonic acid accumulate in COG liver or visceral fats, but the levels of linoleic, eicosadienoic, docosanoic, and dihomo-γ-linolenic acid decrease in COG visceral fats. However, these FAs levels increased in SOG liver or visceral fats except dihomo-γ-linolenic and arachidonic acid which changed insignificantly. The trend of initial upregulation and then downregulation of lipid metabolism-related genes expression is noted in COG liver, including stearoyl-CoA desaturase. Upregulation of adiponectin (ADPN) expression in visceral fats and downregulation of ADPN receptor 2 (Adipo-R2) expression in livers of both HF groups are observed. Correlation analysis revealed positive correlations between specific FAs content and ADPN expression level. Negative correlations are observed between Adipo-R2 expression and the content of oleic, linoleic, and γ-linolenic acid in the SOG liver. Practical applications: Dietary fat not only provides energy but is also associated with lipid homeostasis. In this work, the authors investigate the distribution of fatty acids (FAs) in vivo and their influence on genes related to lipid metabolism induced by diets enriched in oleic acid or linoleic acid. The study suggests that dietary fats modulate lipid homeostasis not only by regulating endogenous FAs levels but also by affecting the expression of genes related to lipid metabolism. This study may support the research in lipid nutrition and rational intake of dietary fat.  相似文献   
957.
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959.
Herein, we report the results of our experimental and computational investigation of the deep drawing behavior of twinning-induced plasticity (TWIP)-cored three-layer steel sheet. Various directional tensile tests for monolayer sheets of the TWIP and low-carbon (LC) steels were performed for evaluation of flow curves and anisotropic coefficients, which are used as input data of the finite element analyses for deep drawing of the monolayer and three-layer sheets. The experimental deep drawing behaviors of the layered sheets of three thickness ratios, and of the monolayer sheets, are computationally analyzed in terms of earring and variations of local thickness along the positions in the drawn cups. It was found that the three-layer sheets are more planar-isotropic in the sense of earring than the monolayer sheets, even more than the TWIP steel sheet. The thickness uniformity along the initial radial direction in the layered sheets is in between the heterogeneous TWIP steel and the relatively homogeneous LC steel. The present results shed light on the future direction of development of steel sheets with planar-isotropic and homogeneous deep-drawing characteristics.  相似文献   
960.
This study was aimed to produce a stable kenaf seed oil-nanostructured lipid carrier (KSO-NLC) sunscreen, which can help in the photoprotective effect. The nanostructured lipid carrier (NLC) formulation was optimized and selected based on the results of mean particle size, polydispersity index (PDI), and storage stability of formulas at both chilled (4 ± 2 °C) and room (25 ± 2 °C) temperatures. Uvinul A plus B was added to KSO-NLC with the optimized formula (80% w/w aqueous phase, 20% w/w lipid phase, and 7% w/w of surfactants with a ratio of 70:15:15 of Tween 20: poloxamer 188: lecithin). The mean particle size distribution (224.73 ± 1.56 nm) and PDI (0.41 ± 0.01) of KSO-NLC were determined and were found to be stable against storage without creaming or phase separation. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging and 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical-scavenging activities of KSO-NLC were 5.43 ± 1.00 mg Trolox equiv. g−1 of NLC and 6.70 ± 0.31 mg Trolox equiv. g−1 of NLC, respectively. The Sun Protection Factor (SPF) of KSO-NLC, 41.38 ± 6.03 with a UVA/UVB ratio 0.64 ± 0.01, suggested a good photoprotective effect. The sustained release of Univul A plus B from KSO-NLC accompanied by its entrapment efficiency up to 64.09 ± 0.98% and drug loading (DL) of 32.05 ± 0.49% (maximum 50% DL capacity) proved that the degradation of the ultraviolet (UV) filter could be reduced. Therefore, the KSO-NLC sunscreen was a feasible solution for the photoprotective approach by using unconventional plant seed oil with a significant enhancement (P < 0.05) in many aspects compared to the formula without KSO incorporation.  相似文献   
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