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991.
To improve the stability of sputter-deposited ZnO:Al (AZO) films at high temperature above 300C, an amorphous Zn-Sn-O (ZTO) film was deposited on the top of AZO films as an protective layer by co-sputtering of pure ZnO and SnO2 targets. Amorphous ZTO films had resistivity in the range from 10−2 to 10−3 Ωcm and were stable up to temperature of 400C. Heat treatments of bare AZO films in the atmosphere at 400C resulted in a dramatic increase in the resistivity accompanied by substantial decrease in carrier concentration and Hall mobility. The AZO films covered with the ZTO film showed remarkable improvement in thermal stability for subsequent heat treatments in the temperature range from 200 to 400C in the atmosphere as well as chemical stability in weak acidic solution. X-ray photoelectron spectroscopy analysis showed that the improvement was attained by ZTO layer acting as diffusion barrier of oxygens and/or water vapors.  相似文献   
992.
电容式集能转换器的设计和优化直接影响自供能装置的整体性能。集能效率的优化可转化为体积约束条件下的拓扑参数优化,由此提出一种改进的球冠型集能转换器拓扑,并在圆环坐标系下基于分离变量法建立了其解析模型。提出储能增量系数的概念,并导出以球冠开口半径与球半径之比为变量的储能增量系数表达式。针对不同尺寸的球冠型拓扑,储能增量系数的实测结果与理论值吻合地较好,从而验证了所建立的球冠型转换器拓扑解析模型的正确性。研究结果为自供能装置集能转换器的优化设计提供了理论依据。  相似文献   
993.
Noncoding RNAs (ncRNAs), in the form of structural, catalytic or regulatory RNAs, have emerged to be critical effectors of many biological processes. With the advent of new technologies, we have begun to appreciate how intracellular and circulatory ncRNAs elegantly choreograph the regulation of gene expression and protein function(s) in the cell. Armed with this knowledge, the clinical utility of ncRNAs as biomarkers has been recently tested in a wide range of human diseases. In this review, we examine how critical factors govern the success of interrogating ncRNA biomarker expression in liquid biopsies and tissues to enhance our current clinical management of human diseases, particularly in the context of cancer. We also discuss strategies to overcome key challenges that preclude ncRNAs from becoming standard-of-care clinical biomarkers, including sample pre-analytics standardization, data cross-validation with closer attention to discordant findings, as well as correlation with clinical outcomes. Although harnessing multi-modal information from disease-associated noncoding RNome (ncRNome) in biofluids or in tissues using artificial intelligence or machine learning is at the nascent stage, it will undoubtedly fuel the community adoption of precision population health.  相似文献   
994.
Composite of multi-walled carbon nanotubes (MWNTs) and titanium (IV) oxide (TiO2) were prepared by a heterogeneous gelation method. The activities of the MWNTs/TiO2 composites were evaluated by photocatalytic oxidative desulfurization using dibenzothiophene (DBT), 4,6-dimethyl dibenzothiophene (4,6-DMDBT), n-tetradecane, and commercial diesel under irradiation using a high-pressure Hg lamp. The microstructures of MWNTs/TiO2 composites were characterized by N2 adsorption, scanning electron microscopy, transmission electron microscope, and X-ray diffraction. It was found that more than 98% of sulfur compounds in commercial diesel were oxidized and removed by the use of the MWNTs/TiO2 composite as a photocatalyst.  相似文献   
995.
The electrolysis of water is considered as a potentially realistic technology for the massive production of hydrogen. The use of graphene composites in electrocatalytic water splitting has been extensively investigated. Graphene-iron oxide composites were prepared via in situ polymerization of 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) and poly (ethylene glycol) monomethacrylate (PEG) on graphene surface (non-oxidative graphite-HOPG/G) in presence of iron oxide nanoparticles (IONPs) and denoted as G-INSCP. Copolymers PMPC-co-PEG (CP) and block copolymer PMPC-b-PEG (BCP) were prepared and their structures were thoroughly characterized. These polymers were used to prepare G-INSCP, G-CP, and G-BCP, their stabilities were compared and their morphologies were studied. HOPG, G-CP, and G-INSCP were used in the hydrogen evolution reaction (HER) as effective platinum catalyst alternatives. G-BCP composite was excluded owing to its very low stability. To evaluate the performance of these electrocatalysts in acidic media, linear sweep voltammetry and electrochemical impedance spectroscopy were employed. Results revealed that, compared with HOPG and G-CP, G-INSCP exhibited a significantly improved catalytic activity with respect to HER in an acidic electrolyte. Additionally, at a current density of 10 mA cm?2, G-INSCP demonstrated a lower overpotential and Tafel slope of 95 mVRHE and 67 mV dec?1, respectively. These observations were attributed to the synergistic effect between the magnetic IONPs and PMPC polymer along with the increase in the electron transfer rate owing to the conductive graphene in the catalyst. Thus G-INSCP catalyst can be a potential candidate for HER and paving the way for the advancement of new and similar catalysts for other applications.  相似文献   
996.
The potential applicability of β-carotene-loaded nanoemulsion (CNE) as a natural colorant in non-smoked sausage made from goat meat surimi-like material (GMS) was elucidated. The effect of CNE content (0–30 g 100 g−1) on the physicochemical characteristic, oxidative stability and β-carotene remaining during cold storage (4 °C) was determined. The higher the CNE, the greater the a*, b* and redness index with the lower L*, and colour likeness score. CNE content had a little impact on the moisture content, aw and pH of sausages over storage period. However, the expressible drip, breaking force and deformation were largely influenced by the CNE content. All CNE-containing sausages displayed a superior oxidative stability to control. Among CNE-incorporated samples, the lowest lipid oxidation and β-carotene degradation were noticeable in the sausage with 10 g 100 g−1 CNE. Thus, the CNE at 10 g 100 g−1 was a promising functional colorant for emulsion sausage made from GMS.  相似文献   
997.
This research investigated for the first time the synthesis of monk fruit seed (Siraitia grosvenorii)-based solid acid catalyst for biodiesel production. The catalyst was synthesized using a two-step surface functionalization method with trimethoxy phenyl silane and chlorosulfonic acid. The as-synthesized catalyst was characterized to ascertain its catalytic characteristics through surface morphology, chemical bonding, and thermal stability. The effects of activating agent impregnation ratio, carbonization temperature, and sulfonation temperature towards fatty acid methyl ester (FAME) yield were elucidated. The esterification reaction with palmitic acid was found to produce FAME yield up to 98.5% with 4 wt.% catalyst loading, 6-h reaction duration and 120°C reaction temperature. The catalyst also demonstrated high reusability with 84.4% FAME yield being successfully maintained after four successive cycles without reactivation. These proved that the as-synthesized catalyst had high prospect to become a suitable low-cost alternative for biodiesel production through catalytic esterification process in the future.  相似文献   
998.
The fatty acid composition of human follicular fluid is important for oocyte development and for pregnancy following in vitro fertilization (IVF). This study investigated whether a dietary intervention that included an increase in marine omega-3 fatty acids, olive oil and vitamin D alters the fatty acid composition of human follicular fluid. The association of lifestyle factors with follicular fluid fatty acid composition was also investigated. Fifty-five couples awaiting IVF were randomized to receive the 6-week treatment intervention of olive oil for cooking, an olive oil-based spread, and a daily supplement drink enriched with vitamin D and the marine omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) and 56 couples were randomized to receive placebo equivalents. Dietary questionnaires were completed, and samples of blood were taken before and after the intervention. Follicular fluid was collected at oocyte retrieval and the fatty acid profile assessed using gas chromatography. In the control group, individual fatty acids in red blood cells and follicular fluid were significantly correlated. Furthermore, a healthier diet was associated with a lower percentage of follicular fluid arachidonic acid. The follicular fluid of women in the treatment group contained significantly higher amounts of EPA and DHA compared to the control group, while the omega-6 fatty acids linoleic, γ-linolenic, dihomo-γ-linolenic, and arachidonic were lower. This is the first report of a dietary intervention altering the fatty acid composition of follicular fluid in humans. Further research is required to determine whether this intervention improves oocyte quality.  相似文献   
999.
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