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31.
M. Müller Manfred Anke Heike Illing-Günther 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1997,205(3):242-247
The aluminium content in wild mushrooms (n = 271, 19 species) and in cultivated Agaricus bisporus (n = 15) was determined by graphite furnace atomic absorption spectroscopy. With an aluminium content of 30 – 50 μ/g dry matter
(DM) Boletus and Xerocomus species, the most well-known and most popular mushrooms, proved to be poor in aluminium. Several species of the genus Suillus, Macrolepiota rhacodes, Hypholoma capnoides as well as individual samples of Russula ochroleuca and Amanita rubescens contained high aluminium concentrations of about 100 μg/g DM and more. Cultivated Agaricus bisporus had the lowest aluminium content, i. e. 14 μg/g DM. The site, its geological origin as well as the mushroom species influenced
the aluminium content in the fruitbodies: these factors require further investigation. Mushrooms do not contribute significantly
to aluminium intake by humans.
Received: 23 January 1997 相似文献
32.
Aligning DNA and protein sequences is a core technique in molecular biology. Often, it is desirable to include partial prior
knowledge and conditions in an alignment. Going beyond prior work, we aim at the integration of such side constraints in free
combination into alignment algorithms. The most common and successful technique for efficient alignment algorithms is dynamic
programming (DP). However, a weakness of DP is that one cannot include additional constraints without specifically tailoring
a new DP algorithm. Here, we discuss a declarative approach that is based on constraint techniques and show how it can be
extended by formulating additional knowledge as constraints. We take special care to obtain the efficiency of DP for sequence
alignment. This is achieved by careful modeling and applying proper solving strategies. Finally, we apply our method to the
scanning for RNA motifs in large sequences. This case study demonstrates how the new approach can be used in real biological
problems. A prototypic implementation of the method is available at . 相似文献
33.
Mattias Schevenels Sean McGinn Anke Rolvink Jeroen Coenders 《Structural and Multidisciplinary Optimization》2014,50(5):755-774
This paper presents a heuristic design optimization method specifically developed for practicing structural engineers. Practical design optimization problems are often governed by buildability constraints. The majority of optimization methods that have recently been proposed for design optimization under buildability constraints are based on evolutionary computing. While these methods are generally easy to implement, they require a large number of function evaluations (finite element analyses), and they involve algorithmic parameters that require careful tuning. As a consequence, both the computation time and the engineering time are high. The discrete design optimization algorithm presented in this paper is based on the optimality criteria method for continuous optimization. It is faster than an evolutionary algorithm and it is free of tuning parameters. The algorithm is successfully applied to two classical benchmark problems (the design of a ten-bar truss and an eight-story frame) and to a practical truss design optimization problem. 相似文献
34.
35.
Anke Bender Olivia Langhamer Francisco Francisco Johan Forslund Linus Hammar Jan Sundberg Sverker Molander 《河流研究与利用》2023,39(8):1578-1589
Anthropogenic activities and their influences on aquatic systems is an important topic, especially considering the growing interest in using the earth's resources in a sustainable way. One of those anthropogenic activities is the introduction of renewable technologies into the aquatic environment such as instream turbines. Environmental studies around those technologies are often still ongoing due to their novelty. During the spring of 2018, juvenile individuals of two salmonid species, Atlantic salmon and brown trout were released upstream a vertical axis instream turbine in the river Dal (Dalälven) in eastern Sweden. The aim of this study was to investigate the swimming behavior of the salmonids around a small-scale prototype vertical axis instream turbine. The swimming pattern and the possible response of avoiding the vertical axis instream turbine were documented with a multi beam sonar. A control area, next to the turbine, was used as reference. No consistent results were shown for trout as they were passing the control area with a statistically high variation, and specimens were rarely observed in proximity of the turbine, neither if the turbine was operating nor at stand still. Salmon clearly avoided the operating turbine, but did not avoid the turbine when it was at stand still, and was often observed swimming straight through the turbine area. These findings indicate that operating this type of instream turbine in a river affects the swimming behavior of Atlantic salmon but is unlikely to affect its migration paths. For brown trout, the statistical results are inconclusive, although data indicate a response of avoiding the turbine. The species are in little risk to suffer physical harm as no fish entered the rotating turbine, despite very turbid water conditions. 相似文献
36.
Southam AD Lange A Hines A Hill EM Katsu Y Iguchi T Tyler CR Viant MR 《Environmental science & technology》2011,45(8):3759-3767
The ability of targeted and nontargeted metabolomics to discover chronic ecotoxicological effects is largely unexplored. Fenitrothion, an organophosphate pesticide, is categorized as a "red list" pollutant, being particularly hazardous to aquatic life. It acts primarily as a cholinesterase inhibitor, but evidence suggests it can also act as an androgen receptor antagonist. Whole-organism fenitrothion-induced toxicity is well-established, but information regarding target and off-target molecular toxicities is limited. Here we study the molecular responses of male roach ( Rutilus rutilus ) exposed to fenitrothion, including environmentally realistic concentrations, for 28 days. Acetylcholine was assessed in brain; steroid metabolism was measured in testes and plasma; and NMR and mass spectrometry-based metabolomics were conducted on testes and liver to discover off-target toxicity. O-demethylation was confirmed as a major route of pesticide degradation. Fenitrothion significantly depleted acetylcholine, confirming its primary mode of action, and 11-ketotestosterone in plasma and cortisone in testes, showing disruption of steroid metabolism. Metabolomics revealed significant perturbations to the hepatic phosphagen system and previously undocumented effects on phenylalanine metabolism in liver and testes. On the basis of several unexpected molecular responses that were opposite to the anticipated acute toxicity, we propose that chronic pesticide exposure induces an adapting phenotype in roach, which may have considerable implications for interpreting molecular biomarker responses in field-sampled fish. 相似文献
37.
Chao Ma Anke Malessa Arnold J. Boersma Kai Liu Andreas Herrmann 《Advanced materials (Deerfield Beach, Fla.)》2020,32(20):1905309
Electrostatic interactions play a vital role in nature. Biomacromolecules such as proteins are orchestrated by electrostatics, among other intermolecular forces, to assemble and organize biochemistry. Natural proteins with a high net charge exist in a folded state or are unstructured and can be an inspiration for scientists to artificially supercharge other protein entities. Recent findings show that supercharging proteins allows for control of their properties such as temperature resistance and catalytic activity. One elegant method to transfer the favorable properties of supercharged proteins to other proteins is the fabrication of fusions. Genetically engineered, supercharged unstructured polypeptides (SUPs) are just one promising fusion tool. SUPs can also be complexed with artificial entities to yield thermotropic and lyotropic liquid crystals and liquids. These architectures represent novel bulk materials that are sensitive to external stimuli. Interestingly, SUPs undergo fluid–fluid phase separation to form coacervates. These coacervates can even be directly generated in living cells or can be combined with dissipative fiber assemblies that induce life-like features. Supercharged proteins and SUPs are developed into exciting classes of materials. Their synthesis, structures, and properties are summarized. Moreover, potential applications are highlighted and challenges are discussed. 相似文献
38.
39.
Polycrystalline samples of RO1−x
F
x
FeAs (0≤x≤0.25) (R=La, Sm, Gd) were investigated by wavelength-dispersive X-ray spectroscopy (WDX) in the electron microscope to determine the
composition of the samples, in particular the fluorine content. It was found that the measured fluorine content can deviate
considerably from the initial weight. In the lanthanum compound LaO1−x
F
x
FeAs, we found good agreement mainly for x≥0.05, but for x<0.05 the fluorine hardly goes into the sample. For the samarium compound we measured less than half the fluorine in the sample
as initially weighed at all fluorine concentrations. These measured values are taken into account when drawing the electronic
phase diagrams of LaO1−x
F
x
FeAs and SmO1−x
F
x
FeAs. This leads to a more consistent picture of both of the diagrams in comparison to the plot of the initial weight. 相似文献
40.
A prospective naturalistic l-year follow-up study of 39 patients with current panic disorder, 17 remitted panic patients, 46 infrequent panickers, 22 patients with simple phobias, and 45 controls assessed clinical course and variables related to the maintenance of panic attacks. Nearly all panic disorder patients (92%) continued to experience panic attacks, and 41% of the initially remitted patients relapsed. No significant effects of treatments delivered in the community were found. Infrequent panickers tended to be more likely to develop panic disorder (15%) than controls (2%). Maintenance/relapse was most consistently linked with good heartbeat perception, anxiety sensitivity, and avoidance in the different subsamples. Patients with simple phobias or normal controls who experienced their first panic attack during follow-up had shown higher anxiety sensitivity at initial assessment than nonpanickers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献