全文获取类型
收费全文 | 1012篇 |
免费 | 51篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 3篇 |
综合类 | 2篇 |
化学工业 | 348篇 |
金属工艺 | 12篇 |
机械仪表 | 14篇 |
建筑科学 | 59篇 |
能源动力 | 15篇 |
轻工业 | 202篇 |
水利工程 | 6篇 |
石油天然气 | 2篇 |
无线电 | 53篇 |
一般工业技术 | 155篇 |
冶金工业 | 59篇 |
原子能技术 | 4篇 |
自动化技术 | 131篇 |
出版年
2024年 | 3篇 |
2023年 | 8篇 |
2022年 | 43篇 |
2021年 | 42篇 |
2020年 | 38篇 |
2019年 | 18篇 |
2018年 | 30篇 |
2017年 | 26篇 |
2016年 | 31篇 |
2015年 | 31篇 |
2014年 | 42篇 |
2013年 | 72篇 |
2012年 | 64篇 |
2011年 | 70篇 |
2010年 | 66篇 |
2009年 | 60篇 |
2008年 | 57篇 |
2007年 | 55篇 |
2006年 | 49篇 |
2005年 | 51篇 |
2004年 | 35篇 |
2003年 | 22篇 |
2002年 | 25篇 |
2001年 | 11篇 |
2000年 | 22篇 |
1999年 | 12篇 |
1998年 | 8篇 |
1997年 | 10篇 |
1996年 | 10篇 |
1995年 | 6篇 |
1994年 | 13篇 |
1993年 | 7篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 8篇 |
1989年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1976年 | 1篇 |
1934年 | 3篇 |
排序方式: 共有1065条查询结果,搜索用时 15 毫秒
61.
Stephanie Simoncini Hanna Coppola Angela Rocca Isaline Bachmann Estelle Guillot Leila Zippo Franoise Dignat-George Florence Sabatier Romain Bedel Anne Wilson Nathalie Rosenblatt-Velin Jean-Baptiste Armengaud Steeve Mentrey Anne-Christine Peyter Umberto Simeoni Catherine Yzydorczyk 《International journal of molecular sciences》2021,22(18)
Infants born after intrauterine growth restriction (IUGR) are at risk of developing arterial hypertension at adulthood. The endothelium plays a major role in the pathogenesis of hypertension. Endothelial colony-forming cells (ECFCs), critical circulating components of the endothelium, are involved in vasculo-and angiogenesis and in endothelium repair. We previously described impaired functionality of ECFCs in cord blood of low-birth-weight newborns. However, whether early ECFC alterations persist thereafter and could be associated with hypertension in individuals born after IUGR remains unknown. A rat model of IUGR was induced by a maternal low-protein diet during gestation versus a control (CTRL) diet. In six-month-old offspring, only IUGR males have increased systolic blood pressure (tail-cuff plethysmography) and microvascular rarefaction (immunofluorescence). ECFCs isolated from bone marrow of IUGR versus CTRL males displayed a decreased proportion of CD31+ versus CD146+ staining on CD45− cells, CD34 expression (flow cytometry, immunofluorescence), reduced proliferation (BrdU incorporation), and an impaired capacity to form capillary-like structures (Matrigel test), associated with an impaired angiogenic profile (immunofluorescence). These dysfunctions were associated with oxidative stress (increased superoxide anion levels (fluorescent dye), decreased superoxide dismutase protein expression, increased DNA damage (immunofluorescence), and stress-induced premature senescence (SIPS; increased beta-galactosidase activity, increased p16INK4a, and decreased sirtuin-1 protein expression). This study demonstrated an impaired functionality of ECFCs at adulthood associated with arterial hypertension in individuals born after IUGR. 相似文献
62.
Etienne Buscail Guillaume Le Cosquer Fabian Gross Marine Lebrin Laetitia Bugarel Cline Deraison Nathalie Vergnolle Barbara Bournet Cyrielle Gilletta Louis Buscail 《International journal of molecular sciences》2021,22(18)
Between 20 to 25% of Crohn’s disease (CD) patients suffer from perianal fistulas, a marker of disease severity. Seton drainage combined with anti-TNFα can result in closure of the fistula in 70 to 75% of patients. For the remaining 25% of patients there is room for in situ injection of autologous or allogenic mesenchymal stem cells such as adipose-derived stem/stromal cells (ADSCs). ADSCs exert their effects on tissues and effector cells through paracrine phenomena, including the secretome and extracellular vesicles. They display anti-inflammatory, anti-apoptotic, pro-angiogenic, proliferative, and immunomodulatory properties, and a homing within the damaged tissue. They also have immuno-evasive properties allowing a clinical allogeneic approach. Numerous clinical trials have been conducted that demonstrate a complete cure rate of anoperineal fistulas in CD ranging from 46 to 90% of cases after in situ injection of autologous or allogenic ADSCs. A pivotal phase III-controlled trial using allogenic ADSCs (Alofisel®) demonstrated that prolonged clinical and radiological remission can be obtained in nearly 60% of cases with a good safety profile. Future studies should be conducted for a better knowledge of the local effect of ADSCs as well as for a standardization in terms of the number of injections and associated procedures. 相似文献
63.
Carole Guillaume Jeremy Pinte Nathalie Gontard Emmanuelle Gastaldi 《Food research international (Ottawa, Ont.)》2010,43(5):1395-1401
The objective of the present work was to understand how the structural, surface, water vapour and gas barrier properties of wheat gluten (WG) coated paper could be influenced by the features of paper. For this purpose, a surface treated paper (TP) and an untreated paper (UTP) were compared. Penetration of WG-coating into the bulk of paper was more pronounced in UTP than TP. This led to the formation of a significant junction zone resulting in an interpenetrated structure for WG–UTP, suggesting a composite-like structure, while a bi-layer one was obtained for WG–TP. Differences in WG penetration were related to the hydrophilicity, roughness and porosity of the paper used. Even though the extent of penetration did not greatly affect the surface properties (water and oil resistance), the transfer properties (water vapour, O2 and CO2) of WG-coated papers were significantly improved when WG-coating highly penetrated: while the WG–TP behaved as a micro-perforated material, the WG–UTP behaved as WG-film. 相似文献
64.
Rachid Boumaza Lydie Huché-Thélier Sabine Demotes-Mainard Eric Le Coz Nathalie Leduc Sandrine Pelleschi-Travier El Mostafa Qannari Soulaiman Sakr Pierre Santagostini Ronan Symoneaux Vincent Guérin 《Food quality and preference》2010,21(8):987-997
The context of ornamental horticulture is considered in order to extend the techniques of sensory and preference evaluation by taking the rosebush as a plant model. In a preliminary study (Boumaza, Demotes-Mainard, Huché-Thélier, & Guérin, 2009), a sensory evaluation was conducted in order to set up a list of attributes. Subsequently, this list was adapted to assess 10 rosebushes. After the control of the panel performance using a multivariate strategy of analysis, the average scores were used in product mapping. The evaluation of the preferences with regard to these rosebushes was undertaken: 253 subjects were asked to rank the products by decreasing order of liking. Thereafter, the preference data were subjected to an internal preference mapping and a cluster analysis. Six homogeneous segments of consumers were eventually retained. By way of performing an external preference mapping, the average ranks were regressed upon the sensory attributes using principal component regression: the preferences of 67% of the consumers were satisfactorily explained by the attributes. 相似文献
65.
Erick B. F. Galante Nathalie Mai Melissa K. Ladyman Philip P. Gill Frederic Coulon 《Journal of Energetic Materials》2021,39(1):85-99
ABSTRACT Energetic materials are often disposed by open-burning or open-detonation as it is a cost-effective and efficient means of destroying explosive material, and often minimizes the need to transport hazardous explosives to treatment facilities. This practice is often scrutinized for the negative environmental impact of the odorous and unsightly toxic gaseous emissions as well as the resulting deposition residues, which often contain unburned energetic materials. With the increasing use of Insensitive High Explosive compositions in munitions, it is essential that the potential environmental impact of their disposal is assessed before their extensive use to prevent the kind of contamination incidents experienced with legacy explosives. Therefore, the aim of this work was to develop a controlled laboratory experiment to identify the gaseous emissions and the energetic material residues that are generated through the combustion of the IHE components 3-nitro-1,2,4-triazol-5-one (NTO), 2,4-dinitroanisole (DNAN), and 1,3,5-trinitroperhydro-1,3,5-triazine (RDX). A sealed vial containing small (mg) quantities of energetic material was heated until the energetic material combusted. Gas chromatography/mass spectrometry (GCMS) was used to calculate the oxygen consumption and to identify the gases that were generated. The solid residues were analyzed by high-performance liquid chromatography (HPLC) to quantify unburned energetic material. Results showed that DNAN was the most resistant to burning, thus leaving significant quantities of unreacted starting material in the vial. An interesting observation for the IHE formulation was that DNAN also inhibited the combustion of NTO and RDX. The gases emitted during the open burning of IHE components and mixtures included CO, CO2, and N2O as expected, but the proportions differed when the components and mixture were compared, reflecting the influence of DNAN on the burning behavior. From our data, we concluded that open-burning DNAN-based formulations is an environmentally unfavorable waste-management practice for the disposal of IHEs mainly due to generation of solid residues as well as unburnt DNAN. 相似文献
66.
Gnanou Besse N Audinet N Barre L Cauquil A Cornu M Colin P 《International journal of food microbiology》2006,110(1):43-51
Obtaining quantitative data concerning the relative impact of various factors that may influence bacterial growth is of great importance for microbial risk assessment and predictive microbiology. The objective of this work was to investigate the effect of the initial Listeria monocytogenes density on all the growth parameters of this pathogen (lag phase duration, growth rate and maximum population density attained) on a sterile solid model system mimicking smoked fishery products, and in real cold-smoked salmon, a product likely to be contaminated with L. monocytogenes. Growth of the pathogen was monitored using a sensitive enumeration method, recently developed, based on membrane filtration followed by the transfer of the filter on a selective media [Gnanou Besse, N., Audinet, N., Beaufort, A., Colin, P., Cornu, M. and Lombard, B., 2004. A contribution to the improvement of Listeria monocytogenes enumeration in smoked salmon. International Journal of Food Microbiology, 91, 119-127.]. Depending on the experimental conditions, we found a significant effect of the inoculum size, both on lag phase duration, and on the maximal population attained. Moreover, the effect of the inoculum size on the growth of L. monocytogenes was dependent on a complex set of interactions. Factors which have appeared to impact on this effect include the cells physiological state, the background microflora, the texture of the media and the packaging system. It is important to understand how these interactions affect the growth of Listeria in order to predict and control its development in food. 相似文献
67.
68.
A solar deep-freezing process has been designed. It aims at cooling down a cold box to about −20 °C, using simple flat plate solar collectors operating at 70 °C. This original process involves two cascaded thermochemical systems based on the BaCl2/ammonia reaction. Its working mode is discontinuous as it alternates between a regeneration mode during daytime and a cold production mode during nighttime. A global dynamic model involving the various system components allows the simulation of the process; it predicts the evolution of the components temperatures and the rates of chemical reactions of the system. It also allows the dimensioning of the system components to maintain a 500 l cold box at −20 °C during the 6 sunniest months of the year under typical Mediterranean weather conditions and provide over 80% of the total yearly cooling needs of this box. This requires a solar collector area of 5.8 m2 and 39 kg of reactive salt. The predicted coefficient of performance (COP) is about 0.1 over the year, and the net solar COP, taking into account the collector efficiencies, is 0.05. 相似文献
69.
Nathalie Meunier Myriam Chartier Guy Mercier Jean-Fran?ois Blais 《Canadian Metallurgical Quarterly》2009,135(9):869-875
Many problems are associated with pig manure production like high biochemical oxygen demand, chemical oxygen demand, nitrogen, and phosphorus contents. Manure produces may be used in land spreading for agricultural purposes. Over application of liquid manure or runoff caused by precipitation contribute notably to surface or overland flow of phosphorus. In this study, the LISOX process is proposed for use in medium size farms, namely a 2,000-head swine farm. The LISOX process uses biological passive flotation, without any gas addition, to enable the flocs to rise to the surface. Results show that this technology is able to considerably reduce the solids content in the final effluent to 1.1±0.3% and reached solids content of 17.9±2.6% in the combined solid manure obtained at the end of the LISOX process. Total phosphorus (Pt) concentrations have been reduced from 1,234±428?mg/L to 146±46?mg/L in the final effluent, while a value of Pt of 20.6±7.9?g/kg has been obtained in the final solid fraction of the treated manure. The initial ammonium ion/total phosphorus ratio of 2.3±1.0 has been increased to respectively 16.4±4.6 and 17.6±5.4 after the primary and the secondary flotation, which is clearly much higher than the target value (NH4/Pt>7). 相似文献
70.
This paper describes an object‐oriented interface for the memory management of sparse discrete mathematical operators in numerical scientific applications. The basic data structure we propose is intended to implement and cope with mathematical vectors in sparse format. This structure allows an effective implementation of more complex data structures, such as matrix and matrix‐like objects, to represent the discrete version of differential operators in numerical application codes. A research example concerning adaptive wavelet algorithms illustrates the possible applications.Copyright © 2002 John Wiley & Sons, Ltd. 相似文献