全文获取类型
收费全文 | 1007篇 |
免费 | 68篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 257篇 |
金属工艺 | 15篇 |
机械仪表 | 22篇 |
建筑科学 | 16篇 |
能源动力 | 41篇 |
轻工业 | 213篇 |
水利工程 | 4篇 |
石油天然气 | 3篇 |
无线电 | 88篇 |
一般工业技术 | 159篇 |
冶金工业 | 91篇 |
原子能技术 | 5篇 |
自动化技术 | 152篇 |
出版年
2023年 | 9篇 |
2022年 | 31篇 |
2021年 | 34篇 |
2020年 | 21篇 |
2019年 | 37篇 |
2018年 | 34篇 |
2017年 | 35篇 |
2016年 | 36篇 |
2015年 | 39篇 |
2014年 | 35篇 |
2013年 | 74篇 |
2012年 | 61篇 |
2011年 | 80篇 |
2010年 | 50篇 |
2009年 | 59篇 |
2008年 | 66篇 |
2007年 | 34篇 |
2006年 | 47篇 |
2005年 | 37篇 |
2004年 | 37篇 |
2003年 | 27篇 |
2002年 | 21篇 |
2001年 | 18篇 |
2000年 | 10篇 |
1999年 | 15篇 |
1998年 | 25篇 |
1997年 | 14篇 |
1996年 | 16篇 |
1995年 | 15篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 9篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有1075条查询结果,搜索用时 78 毫秒
51.
Torres Luis Vanderlei Naldi Marcos Antônio Zoqui Eugênio José 《Journal of Materials Science》2021,56(19):11541-11556
Journal of Materials Science - This study sought to analyze the semi-solid behavior of commercial 332 aluminum alloy during thixoforming in a mechanical eccentric press (thixoforging). The... 相似文献
52.
53.
54.
María Dolores López‐Ramírez Ulises Miguel García‐Ventura Fabricio Omar Barroso‐Muñoz Juan Gabriel Segovia‐Hernández Salvador Hernández 《化学工程与技术》2016,39(2):271-275
The esterification of oleic acid and methanol using sulfuric acid as a homogeneous catalyst is studied in reactive‐separation systems. The conversion of the free fatty acid was investigated in two different experiments with the molar ratio of methanol/oleic acid, amount of catalyst, temperature, and reaction time as variables. The conversion of the free fatty acid was found to depend strongly on the molar ratio of methanol/oleic acid. The reaction time had a direct effect on the conversion of the free fatty acid, and this conversion decreased with higher temperature. These results were valuable for a preliminary study on biodiesel production, using an acid homogeneous catalyst in a reactive dividing‐wall distillation column. 相似文献
55.
Guardalben Lucas Gomes Tomé Salvador Paulo Sargento Susana 《Wireless Personal Communications》2017,97(2):2295-2328
Wireless Personal Communications - Mobile multimedia entertainment is pervasive on mobile devices, leading people to access, store and disseminate a diversity of multimedia contents anytime and... 相似文献
56.
Salvador Ros Agustín C. Caminero Roberto Hernández Antonio Robles-Gómez Llanos Tobarra 《The Journal of supercomputing》2014,68(3):1556-1578
In cloud systems, a clear necessity emerges related to the use of efficient and scalable computing resources. For this, accurate predictions on the load of computing resources are a key. Thanks to these accurate predictions, reduced power consumption and enhanced revenue of the system can be achieved, since resources can be ready when users need them and shutdown when they are no longer needed. This work presents an architecture to manage web applications based on cloud computing, which combines both local and public cloud resources. This work also presents the algorithms needed to efficiently manage such architecture. Among them, a load forecasting algorithm has been developed based on Exponential Smoothing. An use case of the e-learning services of our University presenting the behaviour of our architecture has been evaluated through a series of simulations. Among the most remarkable results, power consumption is reduced by 32 % at the cost of 367.31 US$ a month compared with the current architecture. 相似文献
57.
58.
Jorge Mir‐Bel Rosa Oria María L. Salvador 《International Journal of Food Science & Technology》2012,47(7):1369-1377
This study evaluates parameters relating to the mass transfer during the frying of potato cylinders at different temperatures (100, 120 and 140 °C) and moderate vacuum (around 25 kPa). In all cases, there is a linear relation between water loss and fat uptake. The parameters relating to the textural and structural modifications show less marked changes in vacuum fried products compared to those fried under atmospheric pressure. The maximum penetration force reaches 30%–40% of the initial hardness in vacuum frying and 10% for atmospheric pressure frying; starch gelatinization and pectin methylesterase enzyme activity reduce more quickly under atmospheric pressure, although after 240 s both values are negligible. The scanning electron microscopy images verify that the surface of potato cylinders fried under vacuum or atmospheric pressure are completely different as a result of the steam being released at different temperatures. 相似文献
59.
Laura Marise de Freitas Giovana Maria Fioramonti Calixto Marlus Chorilli Ju?aíra Stella M. Giusti Vanderlei Salvador Bagnato Nikolaos S. Soukos Mansoor M. Amiji Carla Raquel Fontana 《International journal of molecular sciences》2016,17(5)
Antimicrobial photodynamic therapy (aPDT) is increasingly being explored for treatment of periodontitis. Here, we investigated the effect of aPDT on human dental plaque bacteria in suspensions and biofilms in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles (MB-NP) and red light at 660 nm. The effect of MB-NP-based aPDT was also evaluated in a clinical pilot study with 10 adult human subjects with chronic periodontitis. Dental plaque samples from human subjects were exposed to aPDT—in planktonic and biofilm phases—with MB or MB-NP (25 µg/mL) at 20 J/cm2
in vitro. Patients were treated either with ultrasonic scaling and scaling and root planing (US + SRP) or ultrasonic scaling + SRP + aPDT with MB-NP (25 µg/mL and 20 J/cm2) in a split-mouth design. In biofilms, MB-NP eliminated approximately 25% more bacteria than free MB. The clinical study demonstrated the safety of aPDT. Both groups showed similar improvements of clinical parameters one month following treatments. However, at three months ultrasonic SRP + aPDT showed a greater effect (28.82%) on gingival bleeding index (GBI) compared to ultrasonic SRP. The utilization of PLGA nanoparticles encapsulated with MB may be a promising adjunct in antimicrobial periodontal treatment. 相似文献
60.
Karina J. Lagos Hilde H. Buzz Vanderlei S. Bagnato María Paulina Romero 《International journal of molecular sciences》2022,23(1)
Within phototherapy, a grand challenge in clinical cancer treatments is to develop a simple, cost-effective, and biocompatible approach to treat this disease using ultra-low doses of light. Carbon-based materials (CBM), such as graphene oxide (GO), reduced GO (r-GO), graphene quantum dots (GQDs), and carbon dots (C-DOTs), are rapidly emerging as a new class of therapeutic materials against cancer. This review summarizes the progress made in recent years regarding the applications of CBM in photodynamic (PDT) and photothermal (PTT) therapies for tumor destruction. The current understanding of the performance of modified CBM, hybrids and composites, is also addressed. This approach seeks to achieve an enhanced antitumor action by improving and modulating the properties of CBM to treat various types of cancer. Metal oxides, organic molecules, biopolymers, therapeutic drugs, among others, have been combined with CBM to treat cancer by PDT, PTT, or synergistic therapies. 相似文献