全文获取类型
收费全文 | 633篇 |
免费 | 63篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 186篇 |
金属工艺 | 19篇 |
机械仪表 | 44篇 |
建筑科学 | 17篇 |
矿业工程 | 1篇 |
能源动力 | 19篇 |
轻工业 | 129篇 |
水利工程 | 10篇 |
石油天然气 | 5篇 |
无线电 | 33篇 |
一般工业技术 | 110篇 |
冶金工业 | 14篇 |
原子能技术 | 4篇 |
自动化技术 | 101篇 |
出版年
2024年 | 2篇 |
2023年 | 12篇 |
2022年 | 28篇 |
2021年 | 45篇 |
2020年 | 41篇 |
2019年 | 41篇 |
2018年 | 66篇 |
2017年 | 40篇 |
2016年 | 44篇 |
2015年 | 28篇 |
2014年 | 35篇 |
2013年 | 65篇 |
2012年 | 46篇 |
2011年 | 58篇 |
2010年 | 21篇 |
2009年 | 23篇 |
2008年 | 24篇 |
2007年 | 15篇 |
2006年 | 11篇 |
2005年 | 5篇 |
2004年 | 9篇 |
2003年 | 7篇 |
2002年 | 4篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1985年 | 1篇 |
排序方式: 共有696条查询结果,搜索用时 78 毫秒
101.
102.
Scientometrics - The theme related to the oil production in the Brazilian territory is not limited to the extraction means, distribution and use of this product, and involves political, cultural... 相似文献
103.
Matheus Henrique Jantsch Viviane Martins Bernardes Juliana Sorraila Oliveira Daniela Ferreira Passos Guilherme Lopes Dornelles Alessandra Guedes Manzoni Fernanda Licker Cabral Jean Lucas Gutknecht da Silva Maria Rosa Chitolina Schetinger Daniela Bitencourt Rosa Leal 《Journal of Food Biochemistry》2021,45(4):e13636
104.
105.
Leonardo Sales Araujo Alessandra Vieira Guimarães Maísa Conceição Siqueira Matheus Campolina Mendes Loic Mallet Dilson Silva dos Santos Luiz Henrique de Almeida 《International Journal of Hydrogen Energy》2021,46(29):16164-16178
The nickel-base superalloy 718 is a precipitation hardened alloy widely used in the nuclear fuel assembly of pressurized water reactors (PWR). However, the alloy can experience failure due to hydrogen embrittlement (HE). The processing route can influence the microstructure of the material and, therefore, the HE degree. In particular, the size and distribution of the (Nb,Ti)C particles can be affected by the processing. In this regard, the objective of this work was to analyze the influence of cold and hot deformation processing routes on the development of the microstructure, and the consequences on mechanical properties and hydrogen embrittlement. Tensile samples were hydrogenated through gaseous charging and compared to non-hydrogenated samples. Characterization was performed via scanning and transmission electron microscopies, as well as electron backscattered diffraction. The processing was effective to promote significant variations in average grain size and length fraction of special Σ3n boundaries, as well as reduction of average (Nb,Ti)C particle size, being these changes more intense for the cold-rolled route. For the mechanical properties, on one side, the cold-rolled route presented the highest increase in ductility for non-hydrogenated samples, while, on the other side, had the highest degree of embrittlement under hydrogen. This dual behavior was attributed to the interaction of hydrogen with the (Nb,Ti)C particles and stringers and its ensuing influence on the fracture processes. 相似文献
106.
De Oliveira PR Bechara GH Denardi SE Oliveira RJ Mathias MI 《Microscopy research and technique》2012,75(1):28-35
In the present study, mice livers were examined following exposure to different doses of fipronil (15, 25, and 50 mg/kg). Histological and histochemical techniques were used to determine the cytotoxic potential of this compound and to assess the damage it caused to livers. Mice were divided into four groups: control group and groups I, II, and III were exposed to 15, 25, and 50 mg/kg fipronil, respectively. Our findings revealed cytological, morphohistological, and histochemical alterations in liver cells of animals from groups I, II, and III compared to group control animals. These changes included Kupffer-cell proliferation, hepatocyte hypertrophy, accumulation and distribution of proteins, polysaccharides, lipids, and vacuoles in the cytoplasm of hepatocytes, and congestion of blood vessels. These phenotypes mainly characterize the following: (a) autophagic processes, (b) steatosis, and (c) cell death by necrosis, which demonstrate the damage caused by fipronil on nontarget organisms in artificial conditions. 相似文献
107.
Fernanda Figueiredo Martins dos Santos Heloisa Cunha Furtado Luiz Henrique de Almeida 《Journal of Failure Analysis and Prevention》2018,18(4):809-818
The operating conditions of a power plant affect its structural integrity due to many degradation mechanisms, among which is creep. Strain measurements constitute a relatively simple and reliable method of obtaining accurate data regarding the capability of engineering materials to withstand loads and of determining stress distribution in all manner of structural components. This work carried out a critical evaluation of the application of a high-temperature strain gage on a strain and stress analysis. The sensor was undergoing a group of long-term creep tests whose results were compared with the creep machine’s acquisition system. The same strain gage was part of a monitoring system and its out some used on the remaining life evaluation a power plant’s pipeline. The methodology consists of online strain monitoring of those components or regions more susceptible to creep failure, which were identified by finite element analysis. The long-term creep tests using high-temperature strain gages showed that the relative position between sensor and the sample necking region exercises great influence on the measured results. Linear relationship between minimum creep rate obtained by strain gages and rupture time values was observed. The power plant pipeline analysis showed that thermomechanical fatigue is the predominant degradation mechanism. 相似文献
108.
System Reliability-Based Design Optimization (RBDO) considers a single system failure probability constraint. The formulation allows different failure modes to compete with each other. Very few methods and benchmark examples involving optimal design considering system behaviour with progressive failure can be found in the literature. In this article, the conventional System RBDO formulation is compared with a risk-based formulation. A benchmark example involving progressive failure of hyper-static truss is addressed. It is demonstrated that typical System RBDO formulations always lead to isostatic structures, since the formulation does not offer any incentive for the permanence of hyper-static members. In the risk-based formulation, failure costs are differentiated with respect to primary member failure, in hyper-static structures (existence of warning before eventual collapse), and failure of isostatic members (no warning). In this formulation, optimal designs also include hyper-static structures. Results presented herein are relevant in the modern context of robust design considering progressive collapse. 相似文献
109.
Moreto Jéferson Aparecido Silva Pedro Henrique Sampaio de Moraes Moura Gabriel da Silva Camila Cristina Ferreira Deusmaque Carneiro da Cunha Thiago Henrique R. Silva Glaura Goulart Rouxinol Francisco de Siervo Abner Gelamo Rogério Valentim 《Journal of Materials Science》2022,57(19):8779-8799
Journal of Materials Science - Flexible self-standing supercapacitor devices (FSSS) have attracted great attention in several areas due to their potential use in a wide range of applications, such... 相似文献
110.
Tânia Brusque Crocetta Luciano Vieira de Araújo Regiani Guarnieri Thaís Massetti Fernando Henrique Inocêncio Borba Ferreira Luiz Carlos de Abreu Carlos Bandeira de Mello Monteiro 《Virtual Reality》2018,22(3):199-209
Virtual reality games for rehabilitation are attracting increasing growth. In particular, there is a demand for games that allow therapists to identify an individual’s difficulties and customize the control of variables, such as speed, size, distance, as well as visual and auditory feedback. This study presents and describes a virtual reality software package (Bridge Games) to promote rehabilitation of individuals living with disabilities and highlights preliminary researches of its use for implementing motor learning and rehabilitation. First, the study presents seven games in the software package that can be chosen by the rehabilitation team, considering the patient’s needs. All game characteristics are described including name, function presentation, objective and valuable measurements for rehabilitation. Second, preliminary results illustrate some applications of two games, considering 343 people with various disabilities and health status. Based on the results, in the Coincident Timing game, there was a main effect of movement sensor type (in this instance the most functional device was the keyboard when compared with Kinect and touch screen) on average time reached by sample analyzed, F(2, 225) = 4.42, p < 0.05. Similarly, in the Challenge! game, a main effect was found for movement sensor type. However, in this case, touch screen provided better performance than Kinect and Leap Motion, F(2, 709) = 5.90, p < 0.01. Thus, Bridge Games is a possible software game to quantify motor learning. Moreover, the findings suggest that motor skills might be practiced differently depending on the environmental interface in which the game may be used. 相似文献