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The reversibility of the giant magnetocaloric effect (MCE) through the magnetic field–induced magnetostructural transformation in Ni–Mn–In‐based alloys is a key issue towards the potential magnetic refrigeration applications. In this work, Co and Cu are simultaneously doped to tune the reversible magnetocaloric properties associated with the magnetostructural transformation. Owing to the integration of large magnetization difference ΔM, suitable transformation entropy ΔStr, and narrow thermal hysteresis ΔThys in a Ni46Co3Mn35Cu2In14 alloy, the reversible field–induced inverse martensitic transformation is realized in a wide temperature range of 30 K under the field of 5T, yielding a maximum reversible magnetic entropy change ΔSMmax of 16.4 J kg−1 K−1. Moreover, under a low field change of 1.5T, a large reversible adiabatic temperature variation ΔTad of 2.5 K is also obtained, representing the highest value so far under the low field change of 1.5T in Ni–Mn‐based alloys. It is demonstrated that multi‐component alloying by combining the effects of appropriate substitutional elements is an effective way to develop high‐performance magnetocaloric materials.  相似文献   
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本文综述了荧光分析方法应用于氨基甲酸酯类农药,有机磷类农药,拟除虫菊酯类农药及新型烟碱类杀虫剂等残留量的快速测定.  相似文献   
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随钻测井系统中井下仪器连续工作,涡轮发电机作为电源优势明显。提出了一种水力性能较高的涡轮模型形式并进行了建模研究。采用Fluent软件对不同叶片参数的涡轮模型进行紊流流场分析优化了涡轮结构。分析了流量、转速对涡轮流场的影响情况。通过地面实验验证了流量、转速、负载与涡轮发电机输出电压的关系。所建立的涡轮模型能够提高涡轮的输出功率并保证其工作寿命。用地面实验验证了仿真结果的正确性。  相似文献   
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Poly-dialkyl phosphonates were synthesized by reacting methyl linoleate with dimethyl, diethyl, and di-n-butyl phosphites in the presence of free radical initiator and positively identified and characterized using gas chromatography–mass spectrometry (GC-MS), nuclear magnetic resonance (NMR; 1H, 13C, 31P), and Fourier transform infrared (FTIR). Neat poly-dialkyl phosphonates and their blends in high-oleic sunflower oil (HOSuO) and polyalphaolefin (PAO-6) base oils were investigated for their physical, chemical, and tribological properties. At room temperature, the poly-dialkyl phosphonates displayed much better solubility in HOSuO than in PAO-6. Solubility in the base oils increased in the order dimethyl?<?diethyl?<?di-n-butyl. Relative to methyl linoleate, the neat poly-dialkyl phosphonates displayed higher density, higher kinematic viscosity, higher oxidation stability, and better cold flow (lower pour point and cloud point) properties. As an additive (0–10% w/w) in HOSuO, increasing concentration of poly-di-n-butyl phosphonate resulted in increasing onset and peak oxidation temperatures and decreasing cloud point. Poly-di-n-butyl phosphonate blends in HOSuO also showed lower four-ball antiwear (AW) coefficient of friction (COF) and wear scar diameter (WSD) than corresponding blends with zinc dialkyl dithiophosphate (ZDDP). As an additive (0–10% w/w) in PAO-6 base oil, poly-di-n-butyl phosphonate displayed lower four-ball antiwear COF and comparable WSD relative to similar blends of ZDDP in PAO-6. The results indicate that poly-dialkyl phosphonates are promising biobased AW additives with comparable or better performance than current petroleum-based commercial AW additives such as ZDDP.  相似文献   
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“控制”(control)决定了人和建成环境的实质关系(Habraken,2000),然而建筑师对项目的控制是有限的,建筑的设计、建造和使用往往受到政府、发展商、建造方、居住者等多方面的制约和影响。当透过建筑形象观察建筑如何被各种不同的利益团体控制,思考建筑形象背后的控制权问题.我们可以获得住宅设计的另一种思路。  相似文献   
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Volatile organic compounds (VOCs) are harmful for humans and the surrounding ecosystem. Emissions from these pollutants have caused a significant reduction in air quality, which has an effect on people's health. Alkanes, alkenes, alcohols, aromatics, and other VOC pollutants have all been broken down by TiO2 photocatalytic processes. Due to several operating inefficiencies and deactivation issues in humid environments, the practical application of photocatalysis has not been realized on a broader scale. The effectiveness of photo-oxidation of VOCs is impacted by a variety of environmental conditions. In the photocatalytic oxidation of the VOCs, relative humidity (RH) is critical. Therefore, it is important to review the recent findings on how humidity affects the photocatalytic breakdown of VOCs in air. To satisfy this need, this work provides a critical review of the related literature with focus on the fundamentals of photocatalysis, photocatalytic degradation of air pollutants, and the influence of humidity on the photocatalytic process degradation for selected air pollutants. It also highlights the kinetic models and typical photocatalytic reactor and supports for VOC removal.  相似文献   
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It is desirable to quickly check the composition of lipids in small size samples, but achieving this is challenging using the existing staining methods. Herein, a highly sensitive and semi-quantitative method is developed for analysis of lipid samples with ceric ammonium molybdate (CAM) staining. The CAM detection method is systematically evaluated with a wide range of lipid classes including phospholipids, sphingolipids, glycerolipids, fatty acids (FA), and sterols, demonstrating high sensitivity, stability, and overall efficiency. Additionally, CAM staining provides a clean yellow background in high performance thin-layer chromatography (HPTLC) which facilitates quantification of lipids using image processing software. Lipids can be stained with CAM reagent regardless of their head group types, position of the carbon–carbon double bonds, geometric isomerism, and the variation in the length of FA chain, but staining is mostly affected by the degree of unsaturation of the FA backbone. The mechanism of the CAM staining of lipids is proposed on principles of the reduction–oxidation reaction, in which Mo(VI) oxidizes the unsaturated lipids into carbonyl compounds on the HPTLC plate upon heating, while itself being reduced to Mo(IV). This method is applied for the separation, identification, and quantification of lipid extracts from porcine brain. Practical applications: The CAM staining method that is developed in this work shows a high sensitivity for diverse lipid classes following HPTLC separation. HPTLC with CAM staining is a promising method for quick assessment of the identity and quantity of diverse lipid classes in lipid extracts of small size biological samples.  相似文献   
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