全文获取类型
收费全文 | 574篇 |
免费 | 25篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 12篇 |
综合类 | 1篇 |
化学工业 | 132篇 |
金属工艺 | 21篇 |
机械仪表 | 11篇 |
建筑科学 | 18篇 |
矿业工程 | 2篇 |
能源动力 | 38篇 |
轻工业 | 47篇 |
水利工程 | 7篇 |
无线电 | 43篇 |
一般工业技术 | 143篇 |
冶金工业 | 54篇 |
原子能技术 | 7篇 |
自动化技术 | 66篇 |
出版年
2023年 | 9篇 |
2022年 | 33篇 |
2021年 | 37篇 |
2020年 | 19篇 |
2019年 | 22篇 |
2018年 | 32篇 |
2017年 | 30篇 |
2016年 | 22篇 |
2015年 | 15篇 |
2014年 | 33篇 |
2013年 | 54篇 |
2012年 | 31篇 |
2011年 | 32篇 |
2010年 | 25篇 |
2009年 | 16篇 |
2008年 | 14篇 |
2007年 | 15篇 |
2006年 | 19篇 |
2005年 | 10篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 12篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 9篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1980年 | 7篇 |
1979年 | 7篇 |
1978年 | 1篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有602条查询结果,搜索用时 125 毫秒
71.
In this paper a general theory for constructing probability limits for life test data is briefly discussed. It is then applied to a set of life test data to determine which of three specified Weibull distributions give the best fit. 相似文献
72.
A generalization of the Skocpol-Beasley-Tinkham hotspot theory to include an approximate temperature dependence of the conductive heat transfer term of the heat flow equations clearly indicates that the role of the thermal conductivity of the material of the film is not reflected in the observed temperature dependence of the minimum current I
h required to sustain a hotspot in a long, thin-film superconductor. This observation leads to the derivation of a simplified expression for I
h valid for a wider range of bath temperatures. 相似文献
73.
Tapas Kumar Maiti Satya Sopan Mahato Pinaki Chakraborty Chinmay Kumar Maiti Subir Kumar Sarkar 《Journal of Computational Electronics》2010,9(1):1-7
Negative Bias Temperature Instability (NBTI) in p-MOSFETs is a serious reliability concern for digital and analog CMOS circuit
applications. Strain in the channel region affects negative bias temperature instabilities, low frequency noise, radiation
hardness, gate oxide quality and hot carrier performance. The understanding of these phenomena in strain-engineered p-MOSFETs
from fundamental physics is essential. In this paper, technology CAD (TCAD) has been used to study the effects of strain on
the negative bias temperature instabilities in p-MOSFETs. A quasi two dimensional (quasi-2D) physics-based Coulomb scattering
mobility model for strained-Si has been developed and implemented in Synopsys Sentaurus Device tool for device simulation
to understand NBTI in strain-engineered p-MOSFETs. 相似文献
74.
Gargi Basu Ray Soumen Ghosh Satya P. Moulik 《Journal of surfactants and detergents》2009,12(2):131-143
Sodium N-dodecanoyl sarcosinate (SDDS), a novel amino-acid based surfactant, has immense biological and industrial importance. Although
it is being used in a number of cosmetic formulations, systematic analysis of the bulk and interfacial properties of the surfactant
is scarce in the literature. In this study, effects of salt, temperature, and pH on the self-association and related properties
of SDDS have been examined in detail using methods such as tensiometry, conductometry, fluorimetry, pH-metry, spectrophotometry,
calorimetry, and circular dichroism. The nature of amphiphilic packing and the aggregation numbers of the assemblies have
been deciphered. Properties of the acid form of the surfactant have also been explored. The results have been conceptually
rationalized and systematically presented together with associated energetics of the interfacial adsorption and self-aggregation
of the surfactant in the bulk.
相似文献
Satya P. MoulikEmail: Email: |
75.
Majid Soleimani Lope G. Tabil Satya Panigrahi 《Chemical Engineering Communications》2019,206(2):193-206
Hemicellulose in the complex structure of lignocellulosic substances is mainly composed of xylan which is a polymer based on monosaccharide xylose. Using acidic or enzymatic hydrolysis, hemicellulose can be depolymerized into its constituent monomer. The kinetics of hemicellulose depolymerization and decomposition in oat hull was investigated under moderate pressures with catalyst (H2SO4) concentration up to 0.55?N and temperatures of up to 130?°C for a total residence time of 150?min. Different trends of recovery or generation and kinetic mechanisms obtained for the components in the hydrolysate which could be described by different kinetic models, that is, a single-phase kinetic mechanism with product decomposition (two-step sequential reaction) could describe xylose generation. However, generation of arabinose, furfural, and acetic acid followed a single-phase mechanism with no decomposition (one-step reaction). Generation of glucose in the hydrolysate followed a biphasic mechanism due to the fast- and slow-releasing fractions into the liquid phase which was apparently with no decomposition. A pentose recovery of almost 80% was achieved under optimal conditions. Parameters of xylitol bioproduction indicated that a xylitol/xylose conversion yield of 0.80?g/g is achievable from the concentrated hydrolysate with no complementary treatment proving its low toxicity compared to other hemicellulose resources. 相似文献
76.
Faneshwar Kumar Praveen K. Tyagi Nasir Akbar Mir Pramod K. Tyagi Kapil Dev Indrajit Bera Ashim K. Biswas Divya Sharma Asit Baran Mandal Chandra Deo 《Journal of the American Oil Chemists' Society》2019,96(3):261-271
This study investigated the role of flaxseed meal (FSM), a rich terrestrial source of ω-3 fatty acids, in the alteration of the fatty acid profile and metabolism, health indices, physicochemical properties, and sensory quality of broiler chicken meat. The broiler chickens were fed 100 g FSM kg−1 diet for different time periods (1, 2, 3, 4, and 5 weeks). The results revealed that 100 g FSM feeding in broiler chickens for at least 3 weeks increased (P < 0.01) the EPA, DHA, MUFA, PUFA, ω-3 PUFA, and ω-6 PUFA of broiler chicken meat with the corresponding decrease in palmitic acid, stearic acid, and SFA content. 100 g FSM feeding up to 3 weeks has increased the Δ9-desaturases (P < 0.05), thioesterase index (P < 0.01), and Δ5-desaturase + Δ6-desaturase activity (P < 0.01) along with an improvement in health indices (P < 0.01) of chicken meat. Similarly, a reduction in meat cholesterol and fat content of thigh meat (P < 0.01) was observed by feeding 100 g FSM for at least 3 weeks with no effect on the pH, color scores, and sensory evaluation of broiler chicken meat. The water-holding capacity (WHC) and extract release volume (ERV) decreased, whereas, drip loss of meat increased (P < 0.01) due to the feeding of 100 g FSM beyond 3 weeks. Thus, this study concluded that 100 g FSM feeding for 3 weeks in broiler chickens significantly improves the fatty acid profile, lipid metabolism, and health indices of meat, without compromising the physicochemical properties of broiler chicken meat. 相似文献
77.
Silicon - Reinforcements introduced to metal matrix composites are known for their inherent properties like corrosion resistance, wear resistance and machinability. This study deals with the... 相似文献
78.
Satya P. Moulik Animesh K. Rakshit Bappaditya Naskar 《Journal of surfactants and detergents》2021,24(6):535-549
Critical micelle concentration (CMC) is a fundamental physical parameter of surfactant aggregation in solution. The CMC is determined by different methods, tensiometry, conductometry, microcalorimetry, fluorimetry, and so on. However, it is known that though CMC is reported as a single value, in reality, micelle formation occurs over a narrow range of concentration for different experimental procedures produce different results. We shall discuss about a unique procedure of measuring correct CMC applicable to all potential methods used in practice. This is essential for the evaluation of thermodynamic properties of the micelle forming process in pure and mixed states in terms of solution theories. As we in this short documentary want to deal with various aspects of Milton Rosen's research—wherein we have also worked—a few other facets of surfactant chemistry research, besides the micelle formation, are also briefly discussed. In mixed surfactant systems, synergistic effects in various surfactant properties like detergency, foaming, solubilization, and so on are found whereas in some others non-synergistic effects are observed. Dehydration of micelles with an increase in temperature or by the addition of hydrophilic substances may cause clouding to the system. Soluble amphiphilic systems produce Gibbs monolayer at the air/water interface; insoluble amphiphiles form Langmuir monolayers. A documentary of the above aspects will be herein presented and discussed. We mention that this article is neither an original research article nor a review article. This is a mixture of the two: a documentary of both original research and some review of our works presented in memory of Prof. Milton Rosen. 相似文献
79.
Scientometrics - Open Access has emerged as an important movement worldwide during the last decade. There are several initiatives now that persuade researchers to publish in open access journals... 相似文献
80.
Alessandro G. Cassano Siddharth Dev Marianna Maiaru Christopher J. Hansen Scott E. Stapleton 《应用聚合物科学杂志》2021,138(10):49989
Curing of adhesive bondlines is a critical and time-consuming operation in wind turbine blade manufacturing. Significant variation in adhesive thickness can lead to important differences in thermal histories trough the adhesive bonds due to the exothermic nature of the cure process. Reducing bondline cure cycle time and avoiding adhesive overheating are two competing factors in the design of cure temperature cycles. Predictive models on the impact of adhesive thickness variability in bondline cure temperature cycle is currently limited. Adhesive curing and temperature evolution can be simulated by finite element (FE) models coupling the heat transfer problem with the cure kinetics of the adhesive. The cure kinetics of the adhesive system was characterized by isothermal differential scanning calorimetry experiments and implemented in the FE software Abaqus/CAE by user subroutines. Predictions from the FE model were validated experimentally against temperature readings from the curing of 10, 20, and 30 mm thick adhesive bondlines. To highlight the role that predictive models potentially have in the optimization of bondline cure cycles a 2D cross section model representing the trailing edge of a wind turbine blade was used as case study. It was demonstrated that computational models enable customizing cure profiles for nonuniform adhesive thicknesses, ensuring fully cured bondlines with acceptable mechanical properties. 相似文献