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141.
The transport of young calves is a welfare concern. Young calves aged ≤3 mo are particularly vulnerable to compromised welfare, and are at a relatively high risk of morbidity and mortality compared with adult cattle. Calves face several potential challenges to welfare during and after transport, including food and water deprivation, disease, injury, and stress from handling, social mixing, and new environments. The key risk factors identified for poor calf welfare associated with transport include long transport and fasting durations, young age at transport, poor colostral immunity, timing within the calving season, lack of bedding in trucks, and high stocking density. Maximizing calf welfare thus requires a multifaceted approach, such as minimizing transport and fasting durations, transporting at an appropriate stocking density with comfortable bedding, only transporting calves that are healthy and fit, and optimizing pre-transport calf management. More research is needed to understand the effect of transport on the mental or affective state of calves.  相似文献   
142.
Classic storage utilisation is mainly based on charging/discharging strategies enabling a power generation company to generate revenues by buying electricity in low-price periods and selling it at higher prices. Within this paper another feasible way to gain arbitrage in storage utilisation is considered: Strategically increasing demand disregarding existing market prices. This means, charging electricity for storage is not only bought in low price periods, but in all periods where storage charging could influence demand so that market prices increase. This idea is expanded by focussing on another frequently discussed topic which could serve utilities for the same purpose: Automated Demand Side Management (DSM). By using data from Ontario’s electricity market and applying a particular storage and DSM strategy it is analysed to which extent a non-regulated dominant power generation company could influence hourly demand and corresponding prices. It turns out that both strategies analysed derive additional revenues for the dominant power generation company compared to a Business-as-Usual (BAU) case. The results provide an indicator of potential threats for misuse from particular storage or DSM utilisation. Therefore, especially in countries where DSM and/or storage applications are still in its fledgling stages, appropriate market surveillance has to be guaranteed.  相似文献   
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Macrophages are important cells of the innate immune system that play many different roles in host defense, a fact that is reflected by their polarization into many distinct subtypes. Depending on their function and phenotype, macrophages can be grossly classified into classically activated macrophages (pro-inflammatory M1 cells), alternatively activated macrophages (anti-inflammatory M2 cells), and non-activated cells (resting M0 cells). A fast, label-free and non-destructive characterization of macrophage phenotypes could be of importance for studying the contribution of the various subtypes to numerous pathologies. In this work, single cell Raman spectroscopic imaging was applied to visualize the characteristic phenotype as well as to discriminate between different human macrophage phenotypes without any label and in a non-destructive manner. Macrophages were derived by differentiation of peripheral blood monocytes of human healthy donors and differently treated to yield M0, M1 and M2 phenotypes, as confirmed by marker analysis using flow cytometry and fluorescence imaging. Raman images of chemically fixed cells of those three macrophage phenotypes were processed using chemometric methods of unmixing (N-FINDR) and discrimination (PCA-LDA). The discrimination models were validated using leave-one donor-out cross-validation. The results show that Raman imaging is able to discriminate between pro- and anti-inflammatory macrophage phenotypes with high accuracy in a non-invasive, non-destructive and label-free manner. The spectral differences observed can be explained by the biochemical characteristics of the different phenotypes.  相似文献   
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The soft nap and deep pile that impart comfort and warmth to cotton fleece also amplify its flammability. Using ambient aqueous processing, an environmentally benign polyelectrolyte complex (PEC), consisting of poly(allylamine hydrochloride) and sodium hexametaphosphate, was deposited on cotton fleece. This treatment adds only 12.5% weight, reduces peak heat release by 68% and total heat release by 74%, and protects from fire via intumescence. Without treatment, fleece burns aggressively with long afterburn and afterglow times, leaving no residue. With the applied PEC, the fabric self-extinguishes within a few seconds and exhibits no afterglow. In addition, it withstands at least five simulated laundering cycles in alkaline detergent, maintaining a 57% reduction in fire growth capacity afterward. The original soft surface can be restored to the fleece by manual brushing. This simple and environmentally benign treatment provides an opportunity to effectively protect highly flammable textured cellulosic textiles in a safe way.  相似文献   
145.
Gadolinium metal-organic framework (Gd MOF) nanoparticles are an interesting and novel class of nanomaterials that are being studied as a potential replacement for small molecule positive contrast agents in magnetic resonance imaging (MRI). Despite the tremendous interest in these nanoscale imaging constructs, there are limitations, particularly with respect to controlling the particle size, which need to be overcome before these nanoparticles can be integrated into in vivo applications. In an effort to control the size, shape, and size distribution of Gd MOF nanoparticles, hydrotropes were incorporated into the reverse microemulsion synthesis used to produce these nanoparticles. A study of how hydrotropes influenced the mechanism of formation of reverse micelles offered a great deal of information with respect to the physical properties of the Gd MOF nanoparticles formed. Specifically, this study incorporated the hydrotropes, sodium salicylate (NaSal), 5-methyl salicylic acid, and salicylic acid into the reverse microemulsion. Results demonstrated that addition of each of the hydrotropes into the synthesis of Gd MOFs provided a simple route to control the nanoparticle size as a function of hydrotrope concentration. Specifically, Gd MOF nanoparticles synthesized with NaSal showed the best reduction in size distributions in both length and width with percent relative standard deviations being nearly 50% less than nanoparticles produced via the standard route from the literature. Finally, the effect of the size of the Gd MOF nanoparticles with respect to their MRI relaxation properties was evaluated. Initial results indicated a positive correlation between the surface areas of the Gd MOF nanoparticles with the longitudinal relaxivity in MRI. In particular, Gd MOF nanoparticles with an average size of 82 nm with the addition of NaSal, yielded a longitudinal relaxivity value of 83.9 mM?1 [Gd3?] sec?1, one of the highest reported values compared to other Gd-based nanoparticles in the literature to date.  相似文献   
146.
    
Synthesized from hexafluorobenzene, the title compound was found to interconvert readily via bond–shift isomerization and electrocyclization with significant amounts of three other valence isomers. The mobile equilibria were revealed by 19F NMR spectroscopy, and spin–saturation transfer experiments played a key role in identifying the isomers, tracing their interconversions, and assigning their spectra. The influence of fluorine substitution on the stability of carbon–carbon double bonds and of 4-membered rings is discussed in the light of these results.  相似文献   
147.
    
For some time now, certain types of buildings in Germany have been required to undergo a sustainability assessment. Increasingly, that now also includes residential buildings. A research project is currently underway to develop and test suitable criteria for the assessment of small residential buildings, the preliminary results of which were showcased at the BAU 2015 trade fair in Munich. With the help of examples, this article presents the criteria and provides some information on their application.  相似文献   
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Background The U.S. has experienced a shift from a manufacturing‐based economy to one that overwhelmingly provides services and information. This shift demands that technological skills be more fully integrated with one's academic knowledge of science and mathematics so that the next generation of engineers can reason adaptively, think critically, and be prepared to learn how to learn. Purpose (Hypothesis ) Project Lead the Way (PLTW) provides a pre‐college curriculum that focuses on the integration of engineering with science and mathematics. We documented the impact that enrollment in PLTW had on student science and math achievement. We consider the enriched integration hypothesis, which states that students taking PLTW courses will show achievement benefits, after controlling for prior achievement and other student and teacher characteristics. We contrast this with alternative hypotheses that propose little or no impact of the engineering coursework on students' math and science achievement (the insufficient integration hypothesis), or that PLTW enrollment might be negatively associated with student achievement (the adverse integration hypothesis). Design/ Method Using multilevel statistical modeling with students (N = 140) nested within teachers, we report findings from a quantitative analysis of the relationship between PLTW enrollment and student achievement on state standardized tests of math and science. Results While students gained in math and science achievement overall from eighth to tenth grade, students enrolled in PLTW foundation courses showed significantly smaller math assessment gains than those in a matched group that did not enroll, and no measurable advantages on science assessments, when controlling for prior achievement and teacher experience. The findings do not support the enriched integration hypothesis. Conclusions Engineering education programs like PLTW face both challenges and opportunities to effectively integrate academic content as they strive to prepare students for college engineering programs and careers.  相似文献   
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