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51.
The potential of grid-connected solar PV system in Bangladesh was estimated utilizing GeoSpatial toolkit, NASA SSE solar radiation data and HOMER optimization software. Financial viability of solar photovoltaic as an electricity generation source for Bangladesh was also assessed utilizing a proposed 1-MW grid-connected solar PV system using RETScreen simulation software for 14 widespread locations in Bangladesh. The technical potential of gird-connected solar PV in Bangladesh was calculated as about 50174 MW. The annual electricity generation of the proposed system varied depending on the location between 1653 MWh and 1854 MWh, with a mean value of 1729 MWh. Several different economic and financial indicators were calculated, such as the internal rate of return, net present value, benefit-cost ratio, cost of energy production and simple payback. All indicators – for all sites – showed favorable condition for development of the proposed solar PV system in Bangladesh. The results also showed that a minimum of 1423 tons of greenhouse gas emissions can be avoided annually utilizing the proposed system at any part of the country. 相似文献
52.
Abstract—The necessity of using a 3D model is one of the main problems for modeling Roebel bar transposition in turbo-generators by the finite-element method. This article proposes a 2D dual model for computing strand current distribution in the Roebel bar of turbo-generators. Considering the leakage and mutual inductances for each strand and the coupling inductances between them, the end winding region is modeled in this 2D dual model. In this article, the Roebel bar structure including 16 strands was considered, and these distributions are calculated for different transpositions using the finite-element method. In the finite-element method model, the circulating currents are calculated by subtracting a load current at each strand from the total of strand current. Also, for different transpositions, such as 90°, 180°, 360°, and 540°, the circulating currents are calculated using an analytical method. The obtained strand current distributions from the 2D dual model have good agreement with the obtained results from the analytical method for the 180° and 360° transposed coil models. 相似文献
53.
Strengthened Magnetoresistive Epoxy Nanocomposite Papers Derived from Synergistic Nanomagnetite‐Carbon Nanofiber Nanohybrids 下载免费PDF全文
54.
An ambipolar polymer additive for enhanced open circuit voltage in a bulk heterojunction solar cells 下载免费PDF全文
Open circuit voltage (VOC) of organic bulk heterojunction solar cell is extended by the addition of a 20 wt % of F8TBT, an ambipolar polymer in the active layer matrixes (P3HT:PCBM) and then spin casted (1000 rpm/30 s) in the optimized devices on the PEDOT:PSS layer of the ITO glass. A substantial increase in the open circuit voltage from approximately 0.61–0.88 V (44.26%) has been observed with slight increase in efficiency up to 1.91% in the fabricated devices. However, further increment of F8TBT content to 40 wt % reduces the photovoltaic efficiency and affects the JSC values remarkably, possibly due the excess amount of resistance developed. The enhancement of VOC is attributed to the ambipolar nature of F8TBT polymer which facilitates the generated electron and hole transfer at the respective electrodes, enhanced π–π* conjugation in polymer matrix, a superior nanoscale separation, and better molecular conformation at the film interface, thus giving an ample opportunities to explore the impact of blending of materials rather than depositing a thin buffer layer by expensive vapor phase technologies. The details of electrical and microstructure characterization of the film were analyzed by AFM, SEM, UV–Vis, J–V characteristics, and EQE techniques. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43042. 相似文献
55.
Weidong Lu Md Asraful Alam Ying Pan William Junior Nock Zhongming Wang Zhenhong Yuan 《Korean Journal of Chemical Engineering》2016,33(9):2575-2581
The effects of extraction time, extraction temperature, solvent to biomass ratio and solvent composition on lipid yield from lyophilized Chlorococcum sp. biomass using a mixture of ethyl acetate and ethanol (EAE), a new proposed solvent, were studied. Subsequently, the process conditions of extraction by EAE were optimized using Box-Behnken design (BBD). The results revealed that the extraction temperature had the greatest effect on lipid extraction efficiency, followed by volume ratio of ethyl acetate to ethanol (EA/E) and extraction time. The largest lipid extraction yield of 15.74% was obtained under the following extraction conditions: 40mL solvents per gram of biomass for 270 min with gentle stirring at 80 °C by EAE with an EA/E of 1.0. Furthermore, palmitic acid, stearic acid, oleic acid, and linoleic acid were the most abundant fatty acids in the lipids extracted, indicating the great potential of the proposed lipid extraction procedure for microalgae-based biodiesel production. 相似文献
56.
Sourabh Dongaonkar Muhammad A. Alam 《Progress in Photovoltaics: Research and Applications》2015,23(2):170-181
Partial shading in photovoltaic modules is an important reliability and performance concern for all photovoltaic technologies. In this paper, we show how cell geometry can be used as a design variable for improved shade tolerance and performance in monolithic thin film photovoltaic modules (TFPV). We use circuit simulations to illustrate the geometrical aspects of partial shading in typical monolithic TFPV modules with rectangular cells, and formulate rules for shade tolerant design. We show that the problem of partial shading can be overcome by modifying the cell shape and orientation, while preserving the module shape and output characteristics. We discuss two geometrical designs with cells arranged in radial and spiral patterns, which (i) prevent the reverse breakdown of partially shaded cells, (ii) improve the overall power output under partial shading, and (iii) in case of spiral design, may additionally improve the module efficiency by reducing sheet resistance losses. We compare these designs quantitatively using realistic parameters and discuss the practical aspects for their implementation. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
57.
改变MOFs材料的中心金属能影响其气体的亲和性和双组份气体的吸附选择性(如比表面积,孔道结构,内部电场等),本文合成并表征了M-DABCO系列(M=Ni, Co, Cu, Zn) MOFs材料。并应用理想吸附溶液理论(Ideal Adsorbed Solution Theory,简称IAST)量化模拟了环境条件下双组分混合气体(组分比CO2:CH4=40%:60%)的吸附选择性。 Ni-DABCO材料具有良好的CO2吸附性能和在环境条件下对CO2/CH4混合气体的吸附选择性。本文通过实验、表征及计算等来讨论中心金属对M-DABCO系列吸附位点的影响。 相似文献
58.
Bhogal Sangeeta Sharma Gaurav Kumar Amit Sharma Shweta Naushad Mu. Alam Manawwer Stadler Florian J. 《Topics in Catalysis》2020,63(11-14):1272-1285
Topics in Catalysis - In the present study, Ag2O–Al2O3–ZrO2 based trimetallic oxide nanocatalyst was designed using simple microwave assisted reduction method. It was characterized... 相似文献
59.
Md. Sayem Alam Andleeb Z. Naqvi Kabir-ud-Din 《Journal of surfactants and detergents》2007,10(1):35-40
The effect of additives (surfactants and polymers) and pH on the clouding behavior of promethazine hydrochloride (PMT, a phenothiazine
drug) was investigated. Cloud point (CP) decreases with increase in pH due to deprotonation of drug molecules. The same trend
occurs in the presence of surfactants. However, at constant pH, and depending on their structure and nature, these additives
behave differently. Anionic surfactants show peaked behavior, whereas cationic (conventional as well as geminis) and non-ionic
surfactants increase the CP, although the mechanisms differ. Cationic surfactants hinder drug association (due to interaggregate
repulsion) resulting in an increase in CP, while non-ionic surfactants form mixed micelles with the drug, increasing micelle
hydration and CP. Polymers can cause both a decrease as well as an increase in CP, depending on their molecular weight. A
large CP increase (with the increase in surfactant concentration) for gemini surfactants suggests they are excellent candidates
for drug delivery.
相似文献
Kabir-ud-DinEmail: |
60.
The term “conjugated linoleic acid” (CLA) refers to a group of positional and geometric isomers that are derived from linoleic
acid and are found primarily in meat and milk products from ruminant animals. Due to the array of putative benefits associated
with various forms of CLA, there has been recent interest in supplementing human diets with these fatty acids especially when
weight loss is desired. However, in many animal models, CLA has been shown to decrease milk fat production. There is some
concern, therefore, that maternal CLA supplementation during lactation might inadvertently decrease nutrient supply to the
nursing infant. However, there is only limited research on the effect of CLA consumption on milk fat content in women. Based
on previously published work from our laboratory, we hypothesized that CLA supplementation would reduce the milk fat percentage
in lactating women in a dose-dependent manner. Breastfeeding women (n = 12) were assigned randomly to treatments of 4 g/day safflower oil (SFO), 2 g/day CLA plus 2 g/day SFO, or 4 g/day CLA in
a double blind, 3 × 3 Latin square design. Conjugated linoleic acid supplements contained approximately equal amounts of cis9,trans11–18:2 and trans10,cis12–18:2; the two most common isoforms of CLA. Milk was collected by complete breast expression on the last day (day 5) of
each intervention period and analyzed for macronutrient and fatty acid composition. On day 4 of each intervention period,
infant milk consumption was estimated by 24 h weighing of the infant. Washout periods were 9 days in length. We observed a
dose-dependent increase in the concentrations of cis9,trans11–18:2 and trans10,cis12–18:2 in the milk fat. However, we detected neither a change in overall macronutrient composition nor infant milk consumption.
These data do not support those obtained from animal models or our previous human work suggesting that consumption of CLA
mixtures necessarily reduces milk fat. It is possible that either (1) the interpretation of our previously published data
should be reevaluated, and/or (2) there are important intra- and inter-species differences in this regard. 相似文献