全文获取类型
收费全文 | 560篇 |
免费 | 42篇 |
学科分类
工业技术 | 602篇 |
出版年
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 31篇 |
2020年 | 16篇 |
2019年 | 18篇 |
2018年 | 17篇 |
2017年 | 26篇 |
2016年 | 22篇 |
2015年 | 19篇 |
2014年 | 14篇 |
2013年 | 47篇 |
2012年 | 25篇 |
2011年 | 48篇 |
2010年 | 24篇 |
2009年 | 18篇 |
2008年 | 24篇 |
2007年 | 37篇 |
2006年 | 15篇 |
2005年 | 17篇 |
2004年 | 18篇 |
2003年 | 14篇 |
2002年 | 10篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 13篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 16篇 |
1994年 | 9篇 |
1993年 | 17篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有602条查询结果,搜索用时 187 毫秒
1.
Microbial Fuel Cell Application for Azoic Dye Decolorization with Simultaneous Bioenergy Production Using Stenotrophomonas sp. 下载免费PDF全文
Said Galai Antonia Pérez de los Ríos Francisco José Hernández‐Fernández Sihem Haj Kacem Francisco Mateo Ramírez Joaquín Quesada‐Medina 《化学工程与技术》2015,38(9):1511-1518
A single‐chamber air‐cathode microbial fuel cell (MFC) was successfully applied for decolorization of the diazoic dye Reactive Black 5 (RB5) with simultaneous production of electricity. An innovative low‐cost medium, the marine water‐glucose‐yeast extract medium (MWGY), was developed which appears as a textile marine effluent in terms of salinity. The anode compartment containing a single bacterial strain of Stenotrophomonas sp. showed almost complete dye decolorization with different RB5 concentrations after seven days of treatment. For the four dye concentrations used, a correlation between dye removal and production of electrical energy was found. The comparison of the decolorization process in the MFC with that in a batch reactor as control experiment highlights the efficiency of the single‐chamber air‐cathode MFC technology which improved the dye removal by the same bacterial strain. 相似文献
2.
Antonia Loibl Frank Marscheider-Weidemann Katrin Ostertag Sonja Rosenberg Luis Tercero Espinoza Matthias Pfaff Christian Sartorius 《化学,工程师,技术》2020,92(4):414-422
The socio-economic and ecological impacts of selected projects of the BMBF funding program “r4 – Innovative Technologies for Resource Efficiency – Research for the Provision of Raw Materials of Strategic Economic Importance” are presented. Many, but not all, research projects indicate a potential improvement of the supply situation in Germany. In some cases, the provision of secondary raw materials is unprofitable or ecologically detrimental. These cases require a balancing between security of supply and other economic and ecological objectives. 相似文献
3.
Claudia Paredes Francisco J. Martínez-Vázquez Hamada Elsayed Paolo Colombo Antonia Pajares Pedro Miranda 《Journal of the European Ceramic Society》2021,41(1):892-900
Bioactive ceramic scaffolds for bone regeneration consisting of a three-dimensional mesh of interpenetrating struts with square section were fabricated via Digital Light Processing (DLP). The ability of the technique to manufacture 3D porous structures from β-tricalcium phosphate (β-TCP) powders with different dimensions of struts and pores was evaluated, identifying the possibilities and limitations of the manufacturing process. Small pore sizes were found to seriously complicate the elimination of excess slurry from the scaffold’s innermost pores. The effect of the strut/pore size on the mechanical performance of the scaffolds under compressive stresses was also evaluated, but no significant influence was found. Under compressive stresses, the structures resulted weaker when tested perpendicularly to the printing plane due to interlayer shear failure. Interlayer superficial grooves are proposed as potential failure-controlling defects, which could also explain the lack of a Weibull size effect on the mechanical strength of the fabricated DLP scaffolds. 相似文献
4.
Fernando Acebes Javier Pajares José Manuel Galán Adolfo López-Paredes 《International Journal of Project Management》2014
In this paper we propose a new methodology for project control under uncertainty. In particular, we integrate Earned Value Methodology (EVM) with project risk analysis. The methodology helps project managers to know whether the project deviations from planned values are within the “expected” deviations derived from activity planned variability. Although the methodology is new and innovative, we only go back to the fundamentals of project simulation to generate the “universe” of possible projects, according to the assumed variability of project activities. Then we organize and gather the information in order to make the data coherent with EVM. We explain the steps to implement the methodology and we show three case studies. The methodology makes explicit that the schedule and budget resulting from traditional methods like PERT are statistically very optimistic. 相似文献
5.
Maria Cefola Bernardo Pace Lucrezia Sergio Federico Baruzzi Maria Antonia Gatto Antonia Carito Vito Linsalata Nicholas A. Cascarano Donato Di Venere 《International Journal of Food Science & Technology》2014,49(4):1184-1195
Fresh‐cut ‘Big Top’ nectarines were dipped in 2% (w/v) ascorbic acid–1% (w/v) calcium lactate and stored at 4 °C for up to 12 days in 10 kPa O2‐ and 10 kPa CO2‐modified atmosphere packaging (MAP). The used microperforated plastic film allowed O2 and CO2 concentrations to reach steady values from the fifth day in storage onwards. Samples stored in MAP after chemical dipping showed the highest visual quality score, slight browning symptoms, increment in firmness and very low ethanol and acetaldehyde content. The chemical dipping also increased antioxidant capacity, probably due to the effect of ascorbic acid. The results suggested that the control of yeasts was mainly exerted by MAP, whereas only a slight effect was achieved by the chemical dipping. Therefore, MAP plus ascorbic acid/calcium lactate dipping was the best combination to preserve phytochemical content, antioxidant capacity and microbiological safety of fresh‐cut nectarines during storage. 相似文献
6.
7.
8.
9.
10.
Marcelo R. da Silva Luis V. A. Scalvi Luiz H. Dall’Antonia Dayse I. dos Santos 《Journal of Materials Science: Materials in Electronics》2013,24(6):1823-1831
Thin films of the semiconductor NiO are deposited using a straightforward combination of simple and versatile techniques: the co-precipitation in aqueous media along with the dip- coating process. The obtained material is characterized by gravimetric/differential thermal analysis (TG–DTA) and X-ray diffraction technique. TG curve shows 30 % of total mass loss, whereas DTA indicates the formation of the NiO phase about 578 K (305 °C). X-ray diffraction (XRD) data confirms the FCC crystalline phase of NiO, whose crystallinity increases with thermal annealing temperature. UV–Vis optical absorption measurements are carried out for films deposited on quartz substrate in order to avoid the masking of bandgap evaluation by substrate spectra overlapping. The evaluated bandgap is about 3.0 eV. Current–voltage (I–V) curves measured for different temperatures as well as the temperature-dependent resistivity data show typical semiconductor behavior with the resistivity increasing with the decreasing of temperature. The Arrhenius plot reveals a level 233 meV above the conduction band top, which was attributed to Ni2+ vacancy level, responsible for the p-type electrical nature of NiO, even in undoped samples. Light irradiation on the films leads to a remarkable behavior, because above bandgap light induced a resistivity increase, despite the electron–hole generation. This performance was associated with excitation of the Ni2+ vacancy level, due to the proximity between energy levels. 相似文献