全文获取类型
收费全文 | 586篇 |
免费 | 24篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 169篇 |
金属工艺 | 5篇 |
机械仪表 | 13篇 |
建筑科学 | 17篇 |
能源动力 | 21篇 |
轻工业 | 79篇 |
水利工程 | 6篇 |
石油天然气 | 2篇 |
无线电 | 19篇 |
一般工业技术 | 95篇 |
冶金工业 | 45篇 |
原子能技术 | 5篇 |
自动化技术 | 128篇 |
出版年
2023年 | 10篇 |
2022年 | 24篇 |
2021年 | 28篇 |
2020年 | 16篇 |
2019年 | 19篇 |
2018年 | 21篇 |
2017年 | 12篇 |
2016年 | 25篇 |
2015年 | 12篇 |
2014年 | 18篇 |
2013年 | 42篇 |
2012年 | 47篇 |
2011年 | 31篇 |
2010年 | 31篇 |
2009年 | 36篇 |
2008年 | 24篇 |
2007年 | 21篇 |
2006年 | 27篇 |
2005年 | 15篇 |
2004年 | 12篇 |
2003年 | 17篇 |
2002年 | 11篇 |
2001年 | 10篇 |
2000年 | 4篇 |
1999年 | 11篇 |
1998年 | 18篇 |
1997年 | 14篇 |
1996年 | 12篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1974年 | 2篇 |
排序方式: 共有613条查询结果,搜索用时 15 毫秒
601.
Girolamo Di Maio Nicola Alessio Gianfranco Peluso Silverio Perrotta Marcellino Monda Giovanni Di Bernardo 《International journal of molecular sciences》2022,23(20)
Two different types of adipose depots can be observed in mammals: white adipose tissue (WAT) and brown adipose tissue (BAT). The primary role of WAT is to deposit surplus energy in the form of triglycerides, along with many metabolic and hormonal activities; as thermogenic tissue, BAT has the distinct characteristic of using energy and glucose consumption as a strategy to maintain the core body temperature. Under specific stimuli—such as exercise, cold exposure, and drug treatment—white adipocytes can utilize their extraordinary flexibility to transdifferentiate into brown-like cells, called beige adipocytes, thereby acquiring new morphological and physiological characteristics. For this reason, the process is identified as the ‘browning of WAT’. We evaluated the ability of some drugs, including , sildenafil, and rosiglitazone, to induce the browning process of adult white adipocytes obtained from differentiated mesenchymal stromal cells (MSCs). In addition, we broadened our investigation by evaluating the potential browning capacity of IRISIN, a myokine that is stimulated by muscular exercises. Our data indicate that IRISIN was effective in promoting the browning of white adipocytes, which acquire increased expression of UCP1, increased mitochondrial mass, and modification in metabolism, as suggested by an increase of mitochondrial oxygen consumption, primarily in presence of glucose as a nutrient. These promising browning agents represent an appealing focus in the therapeutic approaches to counteracting metabolic diseases and their associated obesity. GW501516相似文献
602.
Souza Vanessa Gimenes Régio Marcio Toesca de Almeida Marcel Gonçalves Farinha Maycon Ulisses Saraiva Bernardo Luciana Virginia Mario Ruviaro Clandio Favarini 《Clean Technologies and Environmental Policy》2023,25(8):2761-2775
Clean Technologies and Environmental Policy - Objective is to analyze the economic feasibility of implementing a greenhouse in a hydroponics production system in substrate (sand) on a small family... 相似文献
603.
604.
Felipe S. Stefanello Yuri G. Kappenberg Juliane N. Araújo Bianca Dozza Pablo A. Nogara João B. T. Rocha Nilo Zanatta Marcos A. P. Martins Helio G. Bonacorso Bernardo A. Iglesias 《Chembiochem : a European journal of chemical biology》2022,23(14):e202200248
A convenient synthesis of a broad series of thirteen examples of alkyne-spacer derivatives 2 from the well-known Sonogashira cross-coupling reaction on diazenyl-pyrazolo[1,5-a]pyrimidin-2-amine compounds 1 is reported. The reactivity of heterocycles 1 due the presence of selected electron-donor (EDG) and electron-withdrawing (EWG) groups attached to different alkynes was evaluated. Also, the reactional versatility due the position variation of the bromo atom at the scaffolds 1 was also investigated. In general, derivatives presented strong absorption bands at the 250–500 nm optical window and UV to cyan emission properties. Also, the redox analysis was recorded by electrochemical cyclic voltammetry technique. For HSA biomacromolecule assays, spectroscopic studies by UV-Vis, steady-state and time-resolved emission fluorescence, and molecular docking calculations evidenced the ability of each compound to establish interactions with human serum albumin (HSA). Finally, the behavior presented for this new class of heterocycles makes them a promising tool as optical sensors for albumins. 相似文献
605.
Maxsueli Aparecida Moura Machado Vinicius Silva Castro Maria Lúcia Guerra Monteiro Yago Alves de Aguiar Bernardo Eduardo Eustáquio de Souza Figueiredo Carlos Adam Conte-Junior 《International Journal of Dairy Technology》2023,76(1):74-80
We aimed at characterising the nonthermal technologies resistance profile of two Escherichia coli strains isolated from pasteurised milk and described as moderate-to-high heat resistance (MHR) (60°C/6 min) harbouring or not a transmissible locus of stress tolerance (tLST). The characterisation was carried out applying optimised conditions of ultraviolet-C light-emitting diodes (UVC-LED) (4950 mJ/cm2), ultrasound (US) (299 W) and their combination (UVC-LED + US). Both strains were more sensitive to UVC-LED (4.5–1.5 log cfu/mL) than to US (<1 log cfu/mL) or UVC-LED + US (4.5–1.5 log cfu/mL), which did not exhibit synergism. Thus, UVC-LED is a promising technology to eliminate E. coli harbouring tLST. 相似文献
606.
Alessandro Andreadis Giuliano Benelli Giovanni Giambene Bernardo Marzucchi 《Wireless Communications and Mobile Computing》2001,1(4):381-395
This paper, based on the PALIO Project within the fifth Research Framework of the European Commission, deals with an information tourist service accessible through mobile phones by means of the Wireless Application Protocol (WAP). We have considered a Global System for Mobile communications (GSM) network where the WAP traffic is transported by the Short Message Service (SMS) on a logical channel that also conveys signaling messages. Suitable models have been considered for both WAP browsing traffic and signaling traffic. We have proposed a theoretical approach to evaluate the mean delay to browse a WAP page taking into account the impact of the signaling load. Analytical predictions have been validated through comparisons with simulation results. Moreover, we have also considered a specific Quality of Service (QoS) requirement in terms of the maximum deck transmission delay that is guaranteed in 95 per cent of cases. Consequently, it has been possible to evaluate the number of WAP users that can be supported per cell. The study carried out in this paper permits to prove the feasibility for the envisaged mobile service based on WAP and it also allows dimensioning WAP pages so that each user experiences reasonable browsing delays. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
607.
Carlos M. Alexandre Bernardo R. Quintella Michaël Ovidio Isabel Boavida Maria J. Costa Arjan P. Palstra Rui L. Pedroso de Lima Maria Isabel P. de Lima João L.M.P. de Lima Pedro R. Almeida 《河流研究与利用》2023,39(3):538-553
Dam construction and streamflow regulation are increasing throughout the world, with impacts in impounded aquatic ecosystems. Hydropower dams, some of them causing a phenomenon called “hydropeaking” during their operation, are known for having a variety of impacts on downstream aquatic biota, particularly fish, and respective habitat. This can result in significant changes, from the community (e.g., fish assemblage structure) to the individual level (e.g., physiological and behavioural adjustments). Researchers and managers involved in the assessment of hydropeaking impacts must be resourceful and use methods that allow their precise evaluation, from large to fine-scale habitat and biological responses. In the last decades, technological advances allowed for the development of techniques and instrumentations that are increasingly being used in hydropeaking impact and mitigation assessments. This paper aims to provide a review, to researchers and managers interested in this field, of some of the most innovative methods and techniques, involving technology, that are available to study hydropeaking effects on downstream ecosystem, particularly from a fish perspective. We discuss the fundamentals behind such techniques, their advantages, and disadvantages, while also providing practical examples of their application and of the type of results that can be obtained. We finish by discussing some of the shortcomings of these methods and how related technology can evolve to solve current limitations. 相似文献
608.
Leso Bernardo Henrique Cortimiglia Marcelo Nogueira Ghezzi Antonio 《Cognition, Technology & Work》2023,25(1):151-179
Cognition, Technology & Work - Contributing to the scarce literature on how companies can deal with their business model of digital transition, this work explores the digital transformation... 相似文献
609.
The material properties of short fiber composites, such as modulus, strength and thermal expansion, are greatly dependent on the fiber orientation state in the composite. Although the orientation pattern is often quite complex, models that allow its prediction have been successfully applied in combination with micromechanical models to calculate moduli and thermal properties. This paper describes the derivation of a model to predict the strength of short fiber composites with arbitrary fiber orientation and fiber length distribution based on classical (micro-) mechanical theories. The predictions are in good agreement with data measured on short fiber composites with different fiber contents. 相似文献
610.
Towpregs are a new class of pre-impregnated materials that can be used to obtain structural composites by compression molding. Consolidation is an important part of this process. In this work, a mathematical model was developed to predict the evolution of the compression pressure during the isothermal consolidation of thermoplastic matrix towpregs. The model relates the applied pressure to operational variables (speed and temperature) and material variables (viscosity, particle size, and polymer volume fraction). Tests were carried out at different temperatures and platen closing speeds, using carbon fiber-reinforced polycarbonate towpregs. The data obtained was compared with theoretical calculations, demonstrating the applicability of the model. 相似文献