全文获取类型
收费全文 | 1016篇 |
免费 | 59篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 8篇 |
化学工业 | 311篇 |
金属工艺 | 5篇 |
机械仪表 | 19篇 |
建筑科学 | 36篇 |
矿业工程 | 7篇 |
能源动力 | 43篇 |
轻工业 | 147篇 |
水利工程 | 12篇 |
石油天然气 | 4篇 |
无线电 | 49篇 |
一般工业技术 | 172篇 |
冶金工业 | 45篇 |
原子能技术 | 5篇 |
自动化技术 | 213篇 |
出版年
2023年 | 9篇 |
2022年 | 28篇 |
2021年 | 50篇 |
2020年 | 25篇 |
2019年 | 46篇 |
2018年 | 33篇 |
2017年 | 41篇 |
2016年 | 44篇 |
2015年 | 36篇 |
2014年 | 38篇 |
2013年 | 78篇 |
2012年 | 51篇 |
2011年 | 72篇 |
2010年 | 65篇 |
2009年 | 63篇 |
2008年 | 46篇 |
2007年 | 54篇 |
2006年 | 32篇 |
2005年 | 37篇 |
2004年 | 32篇 |
2003年 | 20篇 |
2002年 | 24篇 |
2001年 | 13篇 |
2000年 | 12篇 |
1999年 | 13篇 |
1998年 | 14篇 |
1997年 | 16篇 |
1996年 | 7篇 |
1995年 | 10篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 2篇 |
排序方式: 共有1076条查询结果,搜索用时 15 毫秒
51.
Gonzalez L. Julio C. Li Wei Gong Yu Jin XueJun 《Metallurgical and Materials Transactions B》2019,50(3):1417-1427
Metallurgical and Materials Transactions B - This paper reports a Galerkin finite-element analysis of carbon partitioning from martensite into austenite during the quenching and partitioning... 相似文献
52.
Justo Pedroche María M Yust Julio Girn‐Calle Manuel Alaiz Francisco Milln Javier Vioque 《Journal of the science of food and agriculture》2002,82(9):960-965
Chickpea protein isolates and the protease alcalase were used for the production of protein hydrolysates that inhibit angiotensin I‐converting enzyme (ACE). The highest degree of inhibition was found in a hydrolysate obtained by 30 min of treatment with alcalase. This hydrolysate was used as starting material for the purification of ACE‐inhibitory peptides. After Biogel P2 gel filtration chromatography and HPLC C18 reverse phase chromatography, four peptides with ACE‐inhibitory activity were purified. Two of them were competitive inhibitors of ACE, while the other two were uncompetitive inhibitors. These results show that chickpea proteins are a good source of ACE‐inhibitory peptides when hydrolysed with the protease alcalase. © 2002 Society of Chemical Industry 相似文献
53.
Diederik Verkest Julio Leao Da Silva Jr. Chantal Ykman Kris Croes Miguel Miranda Sven Wuytack Francky Catthoor Gjalt De Jong Hugo De Man 《The Journal of VLSI Signal Processing》1999,21(3):185-194
MATISSE is a design environment intended for developing systems characterized by a tight interaction between control and data-flow behavior, intensive data storage and transfer, and stringent real-time requirements. Matisse bridges the gap from a system specification, using a concurrent object-oriented language, to an optimized embedded single-chip hardware/software implementation. Matisse supports stepwise exploration and refinement of dynamic memory management, memory architecture exploration, and gradual incorporation of timing constraints before going to traditional tools for hardware synthesis, software compilation, and inter-processor communication synthesis. With this approach, specifications of embedded systems can be written in a high-level programming language using data abstraction. Application of MATISSE on telecom protocol processing systems in the ATM area shows significant improvements in area usage and power consumption. 相似文献
54.
This paper pretends to offer design rules for the parameters adjustment of the Dynamic Matrix Control (DMC) to allow an easier starting up. The effect on the time response of each algorithm parameter that can be tuned by the user is studied in an unconstrained system. To this aim, the position of the closed loop poles of the equivalent system is calculated. To simplify the study and to obtain more direct conclusions the number of poles will be limited using a First Order Plus Death Time simplification of the real plant. Design rules proposed in this study are tested in some simulated benchmarks and in a real plant. 相似文献
55.
56.
This paper describes an innovative application of discrete-event simulation to model and evaluate differences in business processes following the introduction of new information technologies. Validated models can be used by offices considering the new technology to calibrate existing work loads and then to predict the expected impact of new information technology on measurable business metrics. Following the introduction of the technology, this model may assist in the real-time verification of user paths incorporated in software support tools. This paper will be of interest to those evaluating the impact of information technology and public construction contract administration. 相似文献
57.
Due to the increase in the number and popularity of applications such as e-commerce or on-line booking systems, typical of the Web 2.0, dynamic contents are becoming more and more frequent. This trend suggests the review of widely accepted paradigms and models for the World Wide Web. As a system that is continuously changing, both in the offered applications and in its infrastructure, performance evaluation studies are a main concern to provide sound proposals when designing new web-related systems. Although the dynamism in the workload characterization has also been tackled in previous research, it has not been modeled in a precise way yet because of its complex nature.In this paper we propose the Dweb model which represents the dynamism of current web applications in the workload characterization. Dweb is based on three main concepts that allow to model dynamic workload: navigation, workload test and workload distribution. In addition, a dynamic workload generator has been implemented to show the practical application of the proposed model, which has been illustrated through a case study. 相似文献
58.
David Antonio Pereira de Abreu Perfecto Paseiro Losada Julio Maroto José M. Cruz 《Packaging Technology and Science》2011,24(6):353-360
The capacity of the natural antioxidant to retard oxidation of polyunsaturated fatty acids in hake (Merluccius merluccius) muscle was investigated. Hake fillets were packaged in low‐density polyethylene with the natural antioxidant (sample C1 = 7 mg/dm2 film and sample C2 = 24 mg/dm2 film) or without the antioxidant (control sample) and frozen for 12 months at ?20°C. The results confirm the efficacy of an active packaging with a natural antioxidant derived from barley husks to slow the progress of lipid hydrolysis and increase oxidative stability in hake muscle. Determination of peroxide value, conjugated dienes, free fatty acids, thiobarbituric acid reactive substances (TBARS) and anisidine value (AV) proved suitable for studying lipid hydrolysis and primary and secondary lipid oxidation over time. After 6 months of frozen storage, the TBARS levels were lower in hake packed with low‐density polyethylene with the natural antioxidant (C1 and C2) than in the control sample; at month 12, the TBARS values of C1 and C2 were lower (16 and 21%, respectively) than the control samples. AVs observed in samples C1 and C2 at month 9 were lower than those observed in the control sample at month 12. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
59.
A rheological characterization of collagen edible films is proposed through the experimental evaluation of shear elastic modulus, toughness, hydration capability and stress and stretch ratio at fracture. These properties are obtained from hydration, simple extension and compression tests and analyzed through the BST (Blatz, Sharda, & Tschoegl, 1974) hyperelastic model. Also precursor collagen particle suspensions, with solid concentrations in the range 0.5–4% w/w, are studied to evaluate their thixotropic responses in sudden imposed shear rates and shear loops. These responses are a consequence of particle aggregations leading to cluster formations. The particle size distribution function of suspensions is determined via scanning electron microscopy. Films are formed by casting and then fixed through either a coagulation process with a salt solution or a chemical process involving covalent cross-links with glutaraldehyde. Results indicate that these collagen films behave as colloidal particulate networks composed of particles and clusters. Also it is found that the fractal dimension of clusters is an intrinsic property of collagen particle suspensions, independently from the maturation time. Clusters in these suspensions are formed with a rather open architecture (low fractal value) due to rather large particle attractive forces. The evaluation of the BST rheological parameters allows one the estimation of the energy amount required to get film fracture for different collagen and cross-linker concentrations. Since the final films have to satisfy several quality requirements before using, the interplay between their stiffness and toughness is presented and discussed. 相似文献
60.
Supply chain networks need to respond efficiently to operation disruptions, as one of their aims is to guarantee the on time delivery of products. Hence, robustness has become one of the important issues to consider when designing supply networks. There are alternative ways to measure what robustness means in this context. In this paper, we propose a new metric based on the effect on service level of the collapse of active transportation links. Numerical experiments are carried out to understand how different design factors affect robustness. Robustness under a targeted attack is compared with robustness to random failures. Results show that flow complexity (i.e. the number of potential transportation links between supply network nodes) is the most influential factor affecting supply network and its robustness, as well as the service level that can be maintained after disruptions. Thus, diversification both in supply sources and transportation routes seems to be key to robustness. 相似文献