全文获取类型
收费全文 | 723篇 |
免费 | 78篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 312篇 |
金属工艺 | 8篇 |
机械仪表 | 20篇 |
建筑科学 | 23篇 |
矿业工程 | 1篇 |
能源动力 | 22篇 |
轻工业 | 205篇 |
水利工程 | 3篇 |
石油天然气 | 2篇 |
无线电 | 12篇 |
一般工业技术 | 126篇 |
冶金工业 | 28篇 |
自动化技术 | 37篇 |
出版年
2024年 | 4篇 |
2023年 | 13篇 |
2022年 | 55篇 |
2021年 | 67篇 |
2020年 | 40篇 |
2019年 | 43篇 |
2018年 | 37篇 |
2017年 | 38篇 |
2016年 | 38篇 |
2015年 | 22篇 |
2014年 | 47篇 |
2013年 | 68篇 |
2012年 | 62篇 |
2011年 | 61篇 |
2010年 | 39篇 |
2009年 | 39篇 |
2008年 | 19篇 |
2007年 | 20篇 |
2006年 | 18篇 |
2005年 | 6篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2002年 | 8篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 7篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1978年 | 1篇 |
排序方式: 共有801条查询结果,搜索用时 937 毫秒
101.
Mariana Fatobene Ando Sindy Fuhrmann Zhiwen Pan Bruno Poletto Rodrigues Tatsuya Mori Stefan G. Ebbinghaus Katrin Wondraczek Suguru Kitani Lothar Wondraczek 《Journal of the American Ceramic Society》2021,104(10):4991-5000
We use low-temperature heat capacity, low-frequency Raman scattering, and THz time domain spectroscopy in order to scale the vibrational density of states and the Boson peak in SiO2-Al2O3-B2O3 Yb-laser host glasses. When substituting B2O3 for SiO2 at constant Al2O3 dopant level, we find an optimal value for the ratio of B/Al in terms of mixture stability, at which the excess in the electron donor capability of Al2O3 (relative to the SiO2 backbone) is compensated by the more acidic B2O3. At this composition, Al2O3 plays a mediating role in the structure of aluminoborosilicate glasses, facilitating dissolution of Yb2O3 and admixture of B2O3 into the SiO2 network. 相似文献
102.
103.
Harrson S. Santana Alan C. Rodrigues Mariana G. M. Lopes Felipe N. Russo Jo?o L. Silva Jr Osvaldir P. Taranto 《中国化学工程学报》2020,28(1):180-190
The scope of the present research aims at demonstrating the 3D printing use in the manufacturing of microchannels for chemical process applications. A comparison among digital model processing applications for 3D print(slicers) and a print layer thickness analysis were performed. The 3D print fidelity was verified in several devices, including the microchannels' printing with and without micromixer zones. In order to highlight the 3D print potential in Chemical Engineering, the biodiesel synthesis was also carried out in a millireactor manufactured by 3D printing. The millireactor operated under laminar flow regime with a total flow rate of 75.25 ml ? min~(-1)(increment of about 130 times over traditional microdevices used for biodiesel production).The printed millireactor provided a maximum yield of Ethyl Esters of 73.51% at 40 °C, ethanol:oil molar ratio of7 and catalyst concentration of 1.25 wt% and residence time about 10 s. As a result of flow rate increment attained in the millireactor, the number of required units for scaling-up the chemical processes is reduced. Using the approach described in the present research, anyone could produce their own millireactor for chemical process in a simple way with the aid of a 3D printer. 相似文献
104.
Ana Rita Sousa Cláudia Martins-Cruz Mariana B. Oliveira João F. Mano 《Advanced materials (Deerfield Beach, Fla.)》2020,32(2):1906305
Cellular aggregates are used as relevant regenerative building blocks, tissue models, and cell delivery platforms. Biomaterial-free structures are often assembled either as 2D cell sheets or spherical microaggregates, both incompatible with free-form deposition, and dependent on challenging processes for macroscale 3D upscaling. The continuous and elongated nature of fiber-shaped materials enables their deposition in unrestricted multiple directions. Cellular fiber fabrication has often required exogenously provided support proteins and/or the use of biomaterial-based sacrificial templates. Here, the rapid (<24 h) assembly of fiberoids is reported: living centimeter-long scaffold-free fibers of cells produced in the absence of exogenous materials or supplements. Adipose-derived mesenchymal stem cell fiberoids can be easily modulated into complex multidimensional geometries and show tissue-invasive properties while keeping the secretion of trophic factors. Proangiogenic properties studied on a chick chorioallantoic membrane in an ovo model are observed for heterotypic fiberoids containing endothelial cells. These micro-to-macrotissues may find application as morphogenic therapeutic and tissue-mimetic building blocks, with the ability to integrate 3D and 4D full biological materials. 相似文献
105.
Chiappim William Fraga Mariana Amorim Furlan Humber Ardiles David César Pessoa Rodrigo Sávio 《Microsystem Technologies》2022,28(7):1561-1580
Microsystem Technologies - The wearable sensors have attracted a growing interest in different markets, including health, fitness, gaming, and entertainment, due to their outstanding... 相似文献
106.
Mariana Pereira Barbosa Thaís Caroline Buttow Rigolon Larissa Lorrane Rodrigues Borges Valéria Aparecida Vieira Queiroz Paulo César Stringheta Frederico Augusto Ribeiro de Barros 《International Journal of Food Science & Technology》2021,56(9):4746-4755
This work aimed to evaluate the stability of sorghum 3-deoxyanthocyanins (DXA) in model beverages (pH 3.5) elaborated with crude sorghum phenolic extract, containing ascorbic acid and sulphite, under fluorescent light exposure and subjected to heat treatment. There was no significant difference in the DXA degradation during storage under light exposure (24.16%) and absence of light (20.72%). DXA degradation did not differ in the presence of ascorbic acid during storage under light exposure (23.99–25.38%) and absence of light (19.87–21.74%). The addition of sulphite caused an initial bleaching reaction, but as a reversible reaction, the anthocyanin content was higher on the last day of storage compared to the first day. There were no significant differences in total anthocyanin content of all treatments subjected to the heat treatment (80 °C for 5 and 25 min). Thus, crude DXA are very stable under light, additives and heat, and may be useful as natural food colourants. 相似文献
107.
Potential of migration of active compounds from protein‐based films with essential oils to a food and a food simulant
下载免费PDF全文
![点击此处可从《Packaging Technology and Science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Regiane Ribeiro‐Santos Nathália Ramos de Melo Mariana Andrade Ana Sanches‐Silva 《Packaging Technology and Science》2017,30(12):791-798
Migration tests at different temperatures and storage periods were performed to evaluate the release of active compounds from active whey protein films (WPFs) to a food and food simulants. Whey protein film incorporated with different levels of an optimized essential oils (EOs) blend (1%, 2%, 2.7%, and 5%, w/w) were prepared by casting. This blend contained EOs from rosemary and 2 species of cinnamon. Salami was packaged with WPF and stored during 180 days at 5°C. Temperature influenced significantly the migration of compounds (P<.1). It was observed that eucalyptol was the compound that presented the highest potential of migration into 95% ethanol (v/v). After contact of film with salami, it was observed that, in general, more than 50% of active compounds released from WPF to salami. It was observed that higher amounts of active compounds were released to salami than to fatty food simulant. Results suggested that the release of compounds depends on their affinity with the food/food simulant, temperature, their concentration in packaging, and composition of food. Active packaging may ensure the quality of food due the migration of compounds from EO with antimicrobial and antioxidant activity incorporated in the film to the foodstuff. 相似文献
108.
109.
Vítor M. Gaspar Pedro Lavrador João Borges Mariana B. Oliveira João F. Mano 《Advanced materials (Deerfield Beach, Fla.)》2020,32(6):1903975
Bottom-up tissue engineering is a promising approach for designing modular biomimetic structures that aim to recapitulate the intricate hierarchy and biofunctionality of native human tissues. In recent years, this field has seen exciting progress driven by an increasing knowledge of biological systems and their rational deconstruction into key core components. Relevant advances in the bottom-up assembly of unitary living blocks toward the creation of higher order bioarchitectures based on multicellular-rich structures or multicomponent cell–biomaterial synergies are described. An up-to-date critical overview of long-term existing and rapidly emerging technologies for integrative bottom-up tissue engineering is provided, including discussion of their practical challenges and required advances. It is envisioned that a combination of cell–biomaterial constructs with bioadaptable features and biospecific 3D designs will contribute to the development of more robust and functional humanized tissues for therapies and disease models, as well as tools for fundamental biological studies. 相似文献