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排序方式: 共有1092条查询结果,搜索用时 15 毫秒
61.
Valentina V Semenčenko Ljiljana V Mojović Aleksandra P Đukić‐Vuković Milica M Radosavljević Dušanka R Terzić Marija S Milašinović Šeremešić 《Journal of the science of food and agriculture》2013,93(4):811-818
BACKGROUND: Bioethanol is mostly produced from starchy parts of the corn grain kernel leaving significant amounts of valuable by‐products such as dried distillers' grains with solubles (DDGS) which can be used as a substitute for traditional feedstuff. The suitability of six maize hybrids from Serbia was investigated for bioethanol and DDGS production. The correlation between physical and chemical characteristics of the grain, bioethanol yield and quality of the corresponding DDGS was assessed. RESULTS: All hybrids had very different chemical composition and physical characteristics which could allow various applications. The highest bioethanol yield (94.5% of theoretical) and volumetric productivity (2.01 g l?1 h?1) were obtained with hybrid ZP 434 and the lowest with ZP 611k. Regarding chemical composition, all DDGS samples manifested good properties as feed components. Their protein content was higher compared to the kernel. In addition, the samples showed high digestibility and high mineral content, especially of calcium and phosphorus. CONCLUSION: A hybrid ZP 434 was selected as the most promising bioethanol producer. This property is attributed to the highest level of soft endosperm which is more susceptible to starch‐hydrolysing enzymes. A high yield potential per hectare makes it the best candidate for commercial bioethanol production. © 2012 Society of Chemical Industry 相似文献
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64.
Valentina Marchionni Nuno Lopes Luis Mamouros Dídia Covas 《Water Resources Management》2014,28(13):4415-4431
The aim of this paper is the establishment and validation of cost functions for the various assets of sewer systems, namely gravity and raising pipes, manholes and pumping-stations. Costs are defined as a function of the main physical characteristics of the assets, such as, the pipe material and diameter, excavation depth and percentage of pavement (for sewer pipes), the manhole depth (for manholes) and flow rate, pump head and pump power (for pumping stations,). A four-step methodology was followed: 1) data collection, processing and analysis, 2) present value calculation, 3) key parameters identification and cost functions estimation, and 4) cost functions validation. Cost and infrastructure data for construction contracts of sewer systems managed by Águas de Portugal (AdP) were analyzed. Cost functions were estimated based on multiple linear regression analysis and compared with the ones obtained in previous studies. 相似文献
65.
Evaluation of Reliability Indicators for WDNs with Demand-Driven and Pressure-Driven Models 总被引:1,自引:1,他引:0
Tonino Liserra Marco Maglionico Valentina Ciriello Vittorio Di Federico 《Water Resources Management》2014,28(5):1201-1217
Reliability of water distribution networks (WDNs) has received much attention in recent years due to progressive aging of infrastructures and climate change. Several reliability indicators, focusing on hydraulic aspects rather than water quality, have been proposed in literature. Reliability is generally assessed resorting to well established methods coupling hydraulic simulations and stochastic techniques that describe the WDNs hydraulic performance and component availability respectively. Two main algorithms are employed to simulate WDNs: the demand driven approach (DDA) that disregards the physical relationship between actual water demand and nodal pressure, and the pressure driven approach (PDA) that explicitly incorporates it. In this paper, we show how the choice of hydraulic solver may affect reliability indicators. We modify existing quantitative indicators at nodal and network level, and define novel indicators to consider water quality aspects. These indicators are evaluated for three example WDNs; discrepancies between results obtained with the two approaches depend on network size, feeding scheme and skeletonization. Results suggest to use with caution the DDA for reliability assessment at both local and global level. 相似文献
66.
The purpose of this article is to provide a numerically efficient method for the quadratic stabilisation of a class of linear, discrete-time, uncertain, time-varying systems. The considered class of systems is characterised by an interval time-varying (ITV) matrix and constant sensor and actuator matrices. It is required to find a linear time-invariant (LTI) static output feedback controller yielding a quadratically stable closed-loop system independently of the parameter variation rate. The solvability conditions are stated in terms of linear matrix inequalities (LMIs). The set of LMIs includes the stability conditions for the feedback connection of a unique suitably defined extreme plant with an LTI output controller and the positivity of a closed-loop extremal matrix. A consequent noticeable feature of the article is that the total number of LMIs is independent of the number of uncertain parameters. This greatly enhances the numerical efficiency of the design procedure. 相似文献
67.
Permaglas ME771 is a glass-epoxy laminate which is suitable for use at cryogenic temperatures. We have measured the thermal conductivity of a sample of this material between 64 mK and 4.2 K in the direction parallel to the reinforcing fibres, enabling us to make a comparison with the better known material G-10CR. The thermal conductivity follows the form that would be expected for such a material, and is similar to that of G-10CR, which has a similar (room temperature) tensile strength. We comment on some confusion that has arisen over the difference between G-10CR, a material specifically produced for cryogenic use, and G-10, the more common equivalent. 相似文献
68.
Model-Supported Impact Assessment for the Water Sector in Central Germany Under Climate Change—A Case Study 总被引:1,自引:0,他引:1
Fred Fokko Hattermann Mathias Weiland Shaochun Huang Valentina Krysanova Zbigniew W. Kundzewicz 《Water Resources Management》2011,25(13):3113-3134
Climate change challenges water managers and researchers to find sustainable management solutions, in order to avoid undesirable
impacts on water resources, environment and water-dependent sectors. Needed are projections into the future for the main driving
forces, the resulting pressures on water resources, and quantification of the impacts. Modeling studies can play an important
role in investigating, quantifying, and communicating possible impacts of climate change, with account of uncertainty of the
results. However, climate change related impacts and a need for adaptation still play a minor role in current river basin
management plans that have to comply e.g. with the EU Water Framework Directive (WFD). One important reason is that climate
impact assessment is generally done in research institutes, while management plans are designed by practitioners working in
national and regional environmental agencies and water supply companies. Knowledge transfer from science to practice and visa
versa is often missing. In the present study, we propose a methodology and a case study for model-supported decision making
in the water sector applicable to a participatory water resources planning process. The methodology is applied in a case study
investigating climate change impacts on water resources. The case study area is the German State of Saxony-Anhalt, where the
task was to develop a climate change impact assessment including possible adaptation measures as basis for a federal adaptation
directive. 相似文献
69.
Nicoletta Sinelli Lorenzo Cerretani Valentina Di Egidio Alessandra Bendini Ernestina Casiraghi 《Food research international (Ottawa, Ont.)》2010,43(1):369-375
A sensory analysis of 112 virgin olive oils was performed by a fully trained taste panel. The samples were divided in “defective” and “not defective” on the basis of their olfactory attributes. Then, the “not defective” samples were classified into “low”, “medium” and “high” according to the fruity aroma intensity perceived by assessors. All samples were also analysed by FT-NIR and FT-IR spectroscopy and processed by classification methods (LDA and SIMCA). The results showed that NIR and MIR spectroscopy coupled with statistical methods are an interesting technique compared with traditional sensory assessment in classifying olive oil samples on the basis of the fruity attribute. The prediction rate varied between 71.6% and 100%, as average value. The spectroscopic methods, combined with chemometric strategies, could represent a reliable, cheap and fast classification tool, able to draw a complete fingerprint of a food product, describing its intrinsic quality attributes, that include its sensory attributes. 相似文献
70.
Anna Bernasconi Valentina Ciriani Fabrizio Luccio Linda Pagli 《Theory of Computing Systems》2008,42(4):450-464
Autosymmetric functions exhibit a special type of regularity that can speed-up the minimization process. Based on this autosymmetry,
we propose a three level form of logic synthesis, called ORAX (EXOR-AND-OR), to be compared with the standard minimal SOP
(Sum of Products) form.
First we provide a fast ORAX minimization algorithm for autosymmetric functions. The ORAX network for a function f has a first level of at most 2(n−k) EXOR gates, followed by the AND-OR levels, where n is the number of input variables and k is the “autosymmetry degree” of f. In general a minimal ORAX form has smaller size than a standard minimal SOP form for the same function. We show how the
gain in area of ORAX over SOP can be measured without explicitly generating the latter. If preferred, a SOP expression can
be directly derived from the corresponding ORAX. A set of experimental results confirms that the ORAX form is generally more
compact than the SOP form, and its synthesis is much faster than classical three-level logic minimization. Indeed ORAX and
SOP minimization times are often comparable, and in some cases ORAX synthesis is even faster. 相似文献