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51.
The 2BN bremsstrahlung cross section is a well-adapted distribution to describe the radiative processes at low-electron kinetic energy (E(k) < 500 keV). In this work a method to implement this distribution in a Monte Carlo generator is developed. 相似文献
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Mette Schmedes Asker Daniel Brejnrod Eli Kristin Aadland Pia Kiilerich Karsten Kristiansen Hlne Jacques Charles Lavigne Ingvild Eide Graff
yvin Eng Asle Holthe Gunnar Mellgren Jette Feveile Young Ulrik Krmer Sundekilde Bjrn Liaset Hanne Christine Bertram 《Molecular nutrition & food research》2019,63(1)
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HENRIKE HÄBEL AILA SÄRKKÄ MATS RUDEMO CHARLOTTE HAMNGREN BLOMQVIST EVA OLSSON MATIAS NORDIN 《Journal of microscopy》2019,275(3):149-158
Colloidal systems are of importance not only for everyday products, but also for the development of new advanced materials. In many applications, it is crucial to understand and control colloidal interaction. In this paper, we study colloidal particle aggregation of silica nanoparticles, where the data are given in a three-dimensional micrograph obtained by high-angle annular dark field scanning transmission electron microscopy tomography. We investigate whether dynamic models for particle aggregation, namely the diffusion limited cluster aggregation and the reaction limited cluster aggregation models, can be used to construct structures present in the scanning transmission electron microscopy data. We compare the experimentally obtained silica aggregate to the simulated postaggregated structures obtained by the dynamic models. In addition, we fit static Gibbs point process models, which are commonly used models for point patterns with interactions, to the silica data. We were able to simulate structures similar to the silica structures by using Gibbs point process models. By fitting Gibbs models to the simulated cluster aggregation patterns, we saw that a smaller probability of aggregation would be needed to construct structures similar to the observed silica particle structure. 相似文献
55.
Utsey Shawn O.; Giesbrecht Norman; Hook Joshua; Stanard Pia M. 《Canadian Metallurgical Quarterly》2008,55(1):49
This study tested a sociocultural model of stress and coping in a sample of 215 African Americans. Psychological resources (optimism, ego resilience) were modeled as a "nested self" (S. E. Hobfoll, 2001), supported by social resources (family adaptability and cohesion) and cultural resources (racial pride, religiosity). Race-related stress was a significantly more powerful risk factor than stressful life events for psychological distress. Structural equation modeling results confirmed the hypotheses that psychological resources had a significant direct effect in minimizing psychological distress, and social resources had a significant stress-suppressing effect on race-related stress. Theoretical and practical implications for counseling psychologists are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Assessment of water quality in the vicinity of peat extraction sites: The case of Pien‐Saimaa,Finland 下载免费PDF全文
Eija Sääksjärvi Satu‐Pia Reinikainen Marjatta Louhi‐Kultanen 《Water and Environment Journal》2016,30(1-2):157-166
Peatlands have an important global role as carbon sinks. Locally, however, peat bog extraction can cause pollution in nearby watercourses. The aim of this study is to investigate the application of multivariate methods in the renovation and protection of eutrophic lakes surrounded by agricultural and peat extraction areas. The analytical data used in the study originated from a national water quality database and the period studied was 2000–2013. Multivariate methods: Principal Component Analysis (PCA) and Parallel Factor Analysis (PARAFAC) were applied to solve interactions of variables and pollution sources in a complex water ecosystem. Leaching from the peat bog area was found to be the main source of iron, which has an important role as a precipitator of phosphorus in loose sediment and in water. Nutrient ratios had no direct correlation to algae blooms, but high ratios indicated an increased likelihood of an upcoming bloom. 相似文献
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Behavior of austenitic Cr-Ni-(0.14-0.50)N and Cr-Mn-(0.78-1.00)N steels in hot and cold rolling was investigated by rolling
experiments and mechanical testing. Structure of the steels in the as-cast condition and fracture surfaces after the rolling
experiments were investigated using optical and scanning electron microscopy (SEM). Resistance to deformation was calculated
using rolling forces in hot rolling. Increase in strength in the rolling experiments was related to the nitrogen content of
the steels. Resistance to deformation during hot rolling increased with decreasing rolling temperature and with increasing
nitrogen content. In some steels, hot rolling led to edge cracking, which was more a function of impurity than nitrogen content.
Microscopy revealed that the edge cracking occurred along grain boundaries and second phase particles. For the cold-rolled
steels, the highest achievable reductions were limited due to a “crocodiling” phenomenon, that is, opening of the strip end.
Fracture type at the opened strip end was a brittle-like fracture. 相似文献
58.
Pia Sandvik Wiklund Bo Bergman 《Quality and Reliability Engineering International》1999,15(3):191-203
Much research has been devoted to improving the process of identifying active factors from designed experiments. Generally, the proposed methods rely on an estimate of the experimental error. Here we present a method based on the TTT (total time on test) plot, where the scaled TTT transform enables an evaluation of the contrasts independently of the experimental error. The method can be separated into two parts. The first part consists of a transformed TTT plot for a visual evaluation of data. The second part is more formal and utilizes the cumulative TTT statistic for testing the significance of contrasts. A simulation study shows the power of the method compared with competing methods. Five data sets are used to show that the conclusions drawn are consistent with those obtained using other suggested methods. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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