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671.
A Tool for Prioritizing DAGMan Jobs and its Evaluation 总被引:1,自引:0,他引:1
Grzegorz Malewicz Ian Foster Arnold L. Rosenberg Michael Wilde 《Journal of Grid Computing》2007,5(2):197-212
It is often difficult to perform efficiently a collection of jobs with complex job dependencies due to temporal unpredictability
of the Grid. One way to mitigate the unpredictability is to schedule job execution in a manner that constantly maximizes the
number of jobs that can be sent to workers. A recently developed scheduling theory provides a basis to meet that optimization
goal. Intuitively, when the number of such jobs is always large, high parallelism can be maintained, even if the number of
workers changes over time in an unpredictable manner. In this paper we present the design, implementation, and evaluation
of a practical scheduling tool inspired by the theory. Given a DAGMan input file with interdependent jobs, the tool prioritizes
the jobs. The resulting schedule significantly outperforms currently used schedules under a wide range of system parameters,
as shown by simulation studies. For example, a scientific data analysis application, AIRSN, was executed at least 13% faster
with 95% confidence. An implementation of the tool was integrated with the Condor high-throughput computing system.
The research of G. Malewicz was supported in part by NSF Grant ITR-800864. The research of I. Foster and M. Wilde was supported
in part by the NSF GriPhyN project and by the Mathematical, Information, and Computational Sciences Division subprogram of
the Office of Advanced Scientific Computing Research, U.S. Department of Energy, under Contract W-31-109-Eng-38. The research
of A.L. Rosenberg was supported in part by NSF Grant CCF-0342417. 相似文献
672.
Micha Marcinkowski Toma Pilys Damian Garbicz Jan Piwowarski Damian Mielecki Grzegorz Nowaczyk Micha Taube Maciej Gielnik Maciej Kozak Maria Winiewska-Szajewska Ewa Szoajska Janusz Dbski Agnieszka M. Maciejewska Kaja Przygoska Karolina Ferenc Elbieta Grzesiuk Jarosaw Poznaski 《International journal of molecular sciences》2021,22(9)
The FTO protein is involved in a wide range of physiological processes, including adipogenesis and osteogenesis. This two-domain protein belongs to the AlkB family of 2-oxoglutarate (2-OG)- and Fe(II)-dependent dioxygenases, displaying N6-methyladenosine (N6-meA) demethylase activity. The aim of the study was to characterize the relationships between the structure and activity of FTO. The effect of cofactors (Fe2+/Mn2+ and 2-OG), Ca2+ that do not bind at the catalytic site, and protein concentration on FTO properties expressed in either E. coli (ECFTO) or baculovirus (BESFTO) system were determined using biophysical methods (DSF, MST, SAXS) and biochemical techniques (size-exclusion chromatography, enzymatic assay). We found that BESFTO carries three phosphoserines (S184, S256, S260), while there were no such modifications in ECFTO. The S256D mutation mimicking the S256 phosphorylation moderately decreased FTO catalytic activity. In the presence of Ca2+, a slight stabilization of the FTO structure was observed, accompanied by a decrease in catalytic activity. Size exclusion chromatography and MST data confirmed the ability of FTO from both expression systems to form homodimers. The MST-determined dissociation constant of the FTO homodimer was consistent with their in vivo formation in human cells. Finally, a low-resolution structure of the FTO homodimer was built based on SAXS data. 相似文献
673.
Martina Cazzola Jacopo Barberi Sara Ferraris Andrea Cochis Grzegorz Cempura Aleksandra Czyrska-Filemonowicz Lia Rimondini Silvia Spriano 《Advanced Engineering Materials》2023,25(2):2200883
This research aims toward an antibacterial and osteoconductive Ti6Al4V surface by chemical etching–oxidation treatment and in situ reduction of silver nanoparticles. Starting from a previously developed process, already proved to enhance the osteoinductive ability of titanium, different parameters are changed to tailor the amount of silver and its distribution across the surface oxide layer thickness. The samples are characterized by scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, release of silver, biofilm formation (Staphylococcus aureus), and cytocompatibility toward human osteoblasts progenitor cells. The total amount of silver in the surface oxide layer depends only on the concentration of the silver precursor. The time of the addition of the silver precursor, during the oxidation treatment, affects the oxide layer thickness, dimension, and distribution of the nanoparticles across the surface oxide: they are larger and accumulate on the outermost layer, if the addition occurs early. The maximum ion release occurs after 24 h and lasts up to 14 days; the later addition of silver precursors leads to sustaining the silver release for a longer time. The samples prepared with the higher concentration of the silver precursor are bactericide, but highly cytotoxic, whereas the other ones are bacteriostatic and moderately cytotoxic. 相似文献
674.
Grzegorz Mlostoń Róża Hamera-Fałdyga Katarzyna Urbaniak Wolfgang Weigand Heinz Heimgartner 《Journal of Sulfur Chemistry》2018,39(5):516-524
Ferrocenyl thioketones bearing a hetaryl, phenyl or alkyl group as the second substituent react with (trimethylsilyl)diazomethane at ca. ?30°C in THF solution without formation of a stable [3?+?2]-cycloadduct. After the spontaneous evolution of N2, the corresponding sterically crowded 4,4,5,5-tetrasubstituted 2-silylated 1,3-dithiolanes are formed as products of the second [3?+?2]-cycloaddition of the intermediate thiocarbonyl S-methanide with the starting thioketone. After desilylation by treatment with TBAF, they are converted into the corresponding carbanions, which display different stability depending on the type of substituent. The presence of hetaryl and phenyl groups results in the exclusive formation of 1,2-diferrocenyl ethylenes. In contrast, the presence of methyl groups significantly enhances the stability of the carbanion, which by protonation yields trans-4,5-diferrocenyl-4,5-dimethyl-1,3-dithiolane. 相似文献
675.
Classification of the topography of freshly machined, worn and damaged surfaces (e.g. damaged by adhesion, scoring, abrasion, pitting) is still a problem in machine failure analysis. Tribological surfaces often exhibit both a multiscale nature (i.e. different length scales of surface features) and a non-stationary nature (i.e. features which are superimposed on each other and located at different positions on a surface). The most widely used approaches to surface classification are based on the Fourier transform or statistical functions and parameters. Often these approaches are inadequate and provide incorrect classification of the tribological surfaces. The main reason is that these techniques fail to simultaneously capture the multiscale nature and the non-stationary nature of the surface data. A new method, called a hybrid fractal-wavelet method, has recently been developed for the characterization of tribological surfaces in a multiscale and non-stationary manner. In contrast to other methods, this method combines both the wavelets’ inherent ability to characterize surfaces at each individual scale and the fractals’ inherent ability to characterize surfaces in a scale-invariant manner. The application of this method to the classification of artificially generated fractal and tribological surfaces (e.g. worn surfaces) is presented in this paper. The newly developed method has been further modified to better suit tribological surface data, including a new measure of differences between initial and decoded images. The accuracy of this method in the classification of surfaces was assessed. 相似文献
676.
张博文 颜伟 李兆峰 白龙 Grzegorz Cywinski Ivan Yahniuk Krzesimir Szkudlarek Czeslaw Skierbiszewski Jacek Przybytek Dmytro B. But Dominique Coquillat Wojciech Knap 杨富华 《红外与毫米波学报》2018,37(4):389-392
在场效应晶体管太赫兹探测器中,合理的天线设计可以增强晶体管和太赫兹波之间的耦合效率,从而提高太赫兹探测器的响应度.提出一种基于晶体管栅极边缘沟道电场的仿真来设计平面天线的方法.这种方法尤其适用于太赫兹波段晶体管输入阻抗不容易得到的情况.通过流片完成的基于氮化镓高电子迁移率晶体管的太赫兹探测器的响应度测试证实了这种方法的有效性.集成碟形天线和双偶极子天线的太赫兹探测器最大响应度分别在170.7 GHz(1568.4 V/W)和124.3 GHz(1047.2 V/W)频点处测得,这个测试结果接近基于晶体管栅极边缘沟道电场的仿真结果. 相似文献
677.
Removal of chromium(VI) ions and their reduction were studied on the anion exchanger Dowex PSR-2 in the pH range from 1.5 to 10. The parameters of Cr(VI) sorption process on the anion exchanger were calculated based on the most popular isotherm models such as: Freundlich, Langmuir, Temkin, and Dubinin–Radushkevich (D-R). The Langmuir isotherm was the most appropriate to describe Cr(VI) sorption. The Cr(VI) uptake by Dowex PSR-2 was found to follow the pseudo-second-order rate kinetics. Reduction of chromium(VI) in the pH range 1.5–10 was observed using the HPLC-ICP-MS (high-performance liquid chromatography–inductively coupled plasma-mass spectrometry) method. Oxidation of tri-n-butyl quaternary ammonium groups during the chromate (VI) removal process was observed. 相似文献
678.
Marcin Stec Andrzej Czaplicki Grzegorz Tomaszewicz Krzysztof Słowik 《Korean Journal of Chemical Engineering》2018,35(1):129-136
The addition of carbon dioxide to the gasification media during lignite gasification is introduced. The paper presents thermodynamic grounds of CO2 enhanced gasification using a simplified equilibrium model. Experimental tests conducted using a pilot-scale circulating fluidized bed gasifier are discussed. Detailed analysis of the CO2/C ratio on process conditions, namely on the process gas composition, lower heating value and H2/CO ratio, is provided. Process gas composition implies that the gas is suitable for heat and power generation. Alternatively, CO2 enhanced gasification could be considered as a carbon capture and utilization technology when external, renewable heat supply to the process is used. The results thus obtained are the initial step toward development of the CO2 enhanced gasification process. 相似文献
679.
Poly(methyl vinyl ether‐alt‐maleic anhydride) functionalized with 3‐aminophenylboronic acid: A new boronic acid polymer for sensing diols in neutral water
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Amidation of poly(methyl vinyl ether‐alt‐maleic anhydride) with 3‐aminophenylboronic acid was used to prepare a new boronic acid polymer. The binding of catechol dye, Alizarin Red S to the polymer obtained resulted in getting a stable, colored sensor which was used to establish association constants with different diols in competitive assay. The binding of different diols was readily detected by color change and absorbance values measured at 450 nm were used to calculate the association constants. The polymer obtained formed high‐affinity complexes with ribonucleosides, particularly cytidine and uridine. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40778. 相似文献
680.