全文获取类型
收费全文 | 435篇 |
免费 | 19篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 187篇 |
金属工艺 | 5篇 |
机械仪表 | 6篇 |
建筑科学 | 25篇 |
能源动力 | 16篇 |
轻工业 | 74篇 |
水利工程 | 3篇 |
武器工业 | 1篇 |
无线电 | 15篇 |
一般工业技术 | 56篇 |
冶金工业 | 7篇 |
自动化技术 | 55篇 |
出版年
2022年 | 20篇 |
2021年 | 31篇 |
2020年 | 8篇 |
2019年 | 9篇 |
2018年 | 13篇 |
2017年 | 15篇 |
2016年 | 11篇 |
2015年 | 8篇 |
2014年 | 13篇 |
2013年 | 34篇 |
2012年 | 31篇 |
2011年 | 17篇 |
2010年 | 22篇 |
2009年 | 18篇 |
2008年 | 14篇 |
2007年 | 14篇 |
2006年 | 13篇 |
2005年 | 7篇 |
2004年 | 8篇 |
2003年 | 23篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 10篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 7篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 6篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1973年 | 3篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有455条查询结果,搜索用时 15 毫秒
101.
Ryszard Steller Ewa Micewicz Wanda Meissner Jacek Piglowski Jzef Haponiuk 《应用聚合物科学杂志》2006,99(4):1872-1879
Blends of aliphatic polyamides (PA6, PA66, and PA12), containing 0–15 wt % nonepoxidized or epoxidized elastomers (statistical copolymer butadiene–styrene BS/EBS or linear block copolymer styrene–butadiene–styrene SBS/ESBS) were investigated. For PA6‐elastomer blends, taken as an example, it was shown that with increasing blending time, mechanical properties of blends increase, especially, if ESBS copolymer is used. It can be treated as an indirect sign of reactions between components. It was also found that in blends considerable changes of glass temperatures of components occur. Polyamides in blends with elastomers have smaller heats of fusion in comparison with virgin polyamides. It testifies to hindering of PA crystallization by elastomers. In some cases, significant shifts of melting points are also observed. Measurements of water contact angle show that all blends have very similar values of contact angles, which are lower than those of virgin polyamides. Elastomer content does not also affect the blend water uptake. However, it depends on the polyamide and elastomer type contrary to contact angle. Highest water uptake changes are observed in blends of PA66, especially for epoxidized elastomers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1872–1879, 2006 相似文献
102.
Ryszard Petela 《Fuel》1984,63(3):419-422
The exergy balance equation for liquid atomization is discussed and exergetic efficiency of atomization is defined. On the basis of data taken from the literature some calculations of this efficiency have been carried out for the most widespread cases of atomization, i.e., for pressure and pneumatic atomization. The efficiency is low and does not exceed 1%. Some recommendations about how to carry out the full analysis of all items of the exergetic balance have been made. The results of such an analysis would give some indication of possible improvements in atomizer design and operating parameters. 相似文献
103.
Rhodium catalysts, supported on six γ-Al2O3 supports with different crystallinities, were exposed to sequential treatments in hydrogen at 500°C, in oxygen at 760°C, in hydrogen at 500°C and at 760°C, respectively. Samples were characterized by X-ray diffraction and hydrogen chemisorption at various stages in the sequential treatment. Based on the characterization results, it is concluded that the formation of crystalline Rh2O3 is a function of γ-Al2O3 crystallinity; formation of crystalline Rh2O3 increased with increasing crystallinity of γ-Al2O3 during treatment in oxygen at 760°C. The crystalline Rh2O3 formed during treatment in oxygen at 760°C was reduced to Rh metal by hydrogen at 500°C, but most of the Rh did not adsorb hydrogen at room temperature. Subsequent treatment in hydrogen at 760°C increased the hydrogen adsorption capacity by as much as a factor of three. X-ray line broadening measurements showed that oxygen treatment of reduced Rh/γ-Al2O3 at 760°C followed by hydrogen reduction at 500°C resulted in significant increases in Rh crystal size; further treatment in hydrogen at 760°C resulted in additional sintering of Rh. 相似文献
104.
Alina Zalewska Ryszard KrzyminiewskiBernadeta Dobosz Justyna MrozińskaZdzisław Kruczyński 《Materials Chemistry and Physics》2013
The role of metal ions introduced to polymer matrix in the photochemical degradation of material is not fully understood. In this paper, we considered the effect of copper ions on the photochemical changes in Methafilcon A after UV-irradiation. The presence of methacrylic acid in the structure of Methafilcon A increases the loading capacity of these ions. In result, there is observed the production much more radicals after UV-irradiation than in pure matrix, without copper ions. When the time of UV-exposure increases, the EPR signal of trapped Cu(II) ions in the material decreases. This proves the transformation of Cu(II) to a diamagnetic state of stable Cu(I)-intermediates or copper oxides. Simultaneously, in the first 5-min of UV-irradiation there is observed a rapid increase in intensity of the radical signal, which disappears when the exposure time is extended. This mechanism of radical generating is quite different than for Methafilcon A matrix without copper ions. 相似文献
105.
Brian D. Craft Adrian L. Kerrihard Ryszard Amarowicz Ronald B. Pegg 《Comprehensive Reviews in Food Science and Food Safety》2012,11(2):148-173
Abstract: In recent years, much interest has been observed in the field of phenol‐based antioxidants. As a result of this, many analytical methods have been developed for the purpose of the quantification of phenolic and polyphenolic antioxidant capacities in biological materials. Many of these methods have been altered for application toward the in vitro assessment of antioxidant activities in animal and human model systems as well as in vivo. Due to the varied applicability and usage, methods for the assessment of phenol antioxidant capacities have become so widespread that they are often misused. It is the intent of this work to review the chemistry behind the antioxidant activity of phenolics as well as summarize the many methods applicable for the measurement of in vitro phenolic antioxidant capacity. 相似文献
106.
Pawel Dabrowski Maciej Rogala Iwona Pasternak Jacek Baranowski Wlodzimierz Strupinski Marek Kopciuszynski Ryszard Zdyb Mieczyslaw Jalochowski Iaroslav Lutsyk Zbigniew Klusek 《Nano Research》2017,(11):3648-3661
The interaction between graphene and germanium surfaces was investigated using a combination of microscopic and macroscopic experimental techniques and complementary theoretical calculations.Density functional theory (DFT) calculations for different reconstructions of the Ge(001) surface showed that the interactions between graphene and the Ge(001) surface introduce additional peaks in the density of states,superimposed on the graphene valence and conduction energy bands.The growth of graphene induces nanofaceting of the Ge(001) surface,which exhibits well-organized hill and valley structures.The graphene regions covered by hills are of high quality and exhibit an almost linear dispersion relation,which indicates weak graphene-germanium interactions.On the other hand,the graphene component occupying valley regions is significantly perturbed by the interaction with germanium.It was also found that the stronger graphene-germanium interaction observed in the valley regions is connected with a lower local electrical conductivity.Annealing of graphene/Ge(001)/Si(001) was performed to obtain a more uniform surface.This process results in a surface characterized by negligible hill and valley structures;however,the graphene properties unexpectedly deteriorated with increasing uniformity of the Ge(001) surface.To sum up,it was shown that the mechanism responsible for the formation of local conductivity inhomogeneities in graphene covering the Ge(001) surface is related to the different strength of graphene-germanium interactions.The present results indicate that,in order to obtain high-quality graphene,the experimental efforts should focus on limiting the interactions between germanium and graphene,which can be achieved by adjusting the growth conditions. 相似文献
107.
Effects of electrical stimulation applied in combination with shock chilling method on selected quality attributes of beef from young bulls,heifers, and cows carcasses 下载免费PDF全文
108.
109.
Enzymatic modification of protein preparation obtained from water-washed mechanically recovered poultry meat 总被引:1,自引:1,他引:0
Jerzy Stangierski Hanna Maria Baranowska Ryszard Rezler Jacek Kijowski 《Food Hydrocolloids》2008,22(8):1629-1636
Studies were conducted on a protein preparation obtained from washed mechanically recovered poultry meat (MRPM). The effect of addition of 3 g/kg microbial transglutaminase (MTG) to poultry meat protein was evaluated in terms of texture changes by dynamic mechanical analysis (DMA) and nuclear magnetic resonance (NMR) to determine water content in the preparation and its effect on protein. Samples with the addition of MTG were pre-incubated at 5–6 °C for 1.5, 3, 4.5, 6, 7.5, 9 and 24 h. The largest changes for both texture parameters and rheological properties were observed in the interval of approx. 4–7 h incubation. The protein preparation with the enzyme added had significantly higher values of the moduli of elasticity (G1) and losses (G2) in comparison to the control system. Samples with the addition of MTG also showed a higher water-binding capacity. From the NMR studies it was found that the greatest amount of water was bound by protein in the period of approx. 2.5–5 h incubation. After that time an increase was found in the amount of free water in the sample, which suggests that it was displaced from the system by stronger protein–protein bonds. 相似文献
110.