全文获取类型
收费全文 | 394篇 |
免费 | 21篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 4篇 |
综合类 | 2篇 |
化学工业 | 120篇 |
金属工艺 | 1篇 |
机械仪表 | 6篇 |
建筑科学 | 6篇 |
能源动力 | 14篇 |
轻工业 | 78篇 |
水利工程 | 1篇 |
无线电 | 25篇 |
一般工业技术 | 52篇 |
冶金工业 | 70篇 |
原子能技术 | 11篇 |
自动化技术 | 26篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 8篇 |
2021年 | 13篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 12篇 |
2017年 | 6篇 |
2016年 | 9篇 |
2015年 | 7篇 |
2014年 | 13篇 |
2013年 | 24篇 |
2012年 | 14篇 |
2011年 | 35篇 |
2010年 | 18篇 |
2009年 | 16篇 |
2008年 | 23篇 |
2007年 | 19篇 |
2006年 | 19篇 |
2005年 | 18篇 |
2004年 | 10篇 |
2003年 | 14篇 |
2002年 | 14篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 21篇 |
1997年 | 15篇 |
1996年 | 10篇 |
1995年 | 11篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1992年 | 5篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有416条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
In the case of the wet coal charging process in coke oven chamber, it is known that the coking process is uneven and a local carbonization delay occurs. The reason was investigated through a laboratory-scale experiment and a quantitative estimation. A partial carbonization test in a test coke oven replicated the uneven plastic layer and local carbonization delay. It was revealed that most of the gas generated in the uncarbonized coal layer results from the evaporation of condensed water and that steam can break through the plastic layer in a test coke oven. Moreover, the order estimation implied that steam that generates in the uncarbonized coal layer and breaks through the plastic layer has sufficient heat capacity to cool the heating wall and delay the carbonization. It was also shown that the steam pressure peak measured in a commercial coke oven is much lower than the estimated steam pressure in this study assuming steam not breaking through the plastic layer. The above-mentioned results and quantitative investigation strongly support the ‘steam breaking through the plastic layer’ theory proposed by Dr. Rohde that an uneven carbonization process is caused by vaporized coal moisture breaking through the plastic layer at definite, unforeseeable points, which results in cooling of the wall by the steam flow. 相似文献
5.
Elevated serum lipoprotein (a) levels associated with ulcerative colitis in a young Japanese patient
S Kawabata S Katagiri H Negoro A Nogami I Yabuuchi M Gomi R Arima S Tarui 《Canadian Metallurgical Quarterly》1997,36(6):389-391
Thromboembolism has been shown to play a role in the pathogenesis of inflammatory bowel disease (IBD). A possibility exists that lipoprotein (a) [Lp(a)], a newly-discovered prothrombotic factor, also participates in the development of at least some cases of IBD. Marked elevation of serum Lp(a) levels was observed in a young patient with ulcerative colitis. A biopsy specimen of the rectal mucosa showed findings compatible with ulcerative colitis, as well as small vessel thrombus occurring within the muscularis mucosa in the rectum. Serum Lp(a) levels were markedly elevated on admission (71 mg/dl), with a gradual decrease to 46 mg/dl on discharge. Moreover, serum Lp(a) levels decreased in parallel with clinical improvement. In the quiescent clinical stage, no small vessel thrombus was observed in the mucosa on follow-up colonoscopy. The association between IBD and hyper-Lp(a)-emia would be presumable but it has been, to our knowledge, previously unreported. The case reported here would be the first young patient, suggesting the presence of hyper-Lp(a)-emia and small vessel thrombus formation occurring in association with the development of ulcerative colitis. 相似文献
6.
7.
D Miyamoto N Endo N Oku Y Arima T Suzuki Y Suzuki 《Canadian Metallurgical Quarterly》1998,21(12):1258-1262
The cytotoxic effects of beta-thujaplicin and five kinds of metal chelates were examined on mouse melanoma B16BL6 cells by cell viability and lactate dehydrogenase (LDH) release assay. Beta-thujaplicin-zinc chelate and beta-thujaplicin-copper chelate had higher cytotoxic effects than beta-thujaplicin, and the 50% effective doses (ED50) of these metal chelates were 12.5 and 25 microM, respectively. In addition, the zinc chelate induced DNA ladder formation in B16BL6 cells, as shown by the DNA fragmentation assay, suggesting that cell death induced by the zinc chelate is apoptosis. The zinc chelate also had a cytotoxic effect and induced DNA fragmentation on other tumor cell lines: HeLa, Meth A, and B16F1 cells, but not on normal human diploid fibroblasts FS-4. These results suggest that beta-thujaplicin-zinc chelate induces apoptotic cell death in various tumor cell lines and is a potent antitumor agent for tumor cells including malignant melanomas. 相似文献
8.
Monica Bianco Ilenia Viola Miriam Cezza Francesca Pietracaprina Giuseppe Gigli Rosaria Rinaldi Valentina Arima 《Microfluidics and nanofluidics》2012,13(3):399-409
Solid surface/liquid interactions play an important role in microfluidics and particularly in manipulation of films, drops and bubbles, a basic requirement for a number of lab-on-chip applications. The behavior of solvents in coated microchannels is difficult to be predicted considering theories; therefore, experimental methods able to estimate the properties at the interface in real time and during the operational regime are amenable. Here, we propose to use an experimental setup to evaluate the effective dynamics of solvents inside PDMS microchannels. The influence of the solvent properties as well as of the channel wall’s wettability on the fluid movements was evaluated. Modification of the channel properties was achieved by introducing Teflon coatings that allow producing stable hydrophobic microchannel walls. The results were fitted according to Washburn-type power-law and compared with theoretical calculations of the parameter β that expresses the dependence of capillary dynamics on surface tension γ, liquid viscosity η, contact angles θ and the hydraulic radius R H. A comparison between the calculated and the experimental values reveled that parameters other than the contemplated ones influenced the measurements. The main parameter that affects the flow of solvents such as water, methanol ethanol, dimethylformamide, acetonitrile and acetone was found to be the γ/η ratio. Considering these results, the investigation tool described here is believed to be promising to predict the dynamics of common organic solvents inside integrated functional fluidic devices and to accurately control solvent flow, particularly in capillary-driven pumpless systems, a basic requirement for widening the application range of PDMS lab-on-chip devices. 相似文献
9.
Katsuhiko Ariga Takashi Nakanishi Yukiko Terasaka Jun-ichi Kikuchi 《Journal of Porous Materials》2006,13(3):427-430
As a soft and flexible porous structure, a pore array of a steroid cyclophane SC(OH), which consists of the rigid 1,6,20,25-tetraaza[6.1.6.1]paracyclophane
ring connected to four steroid moieties (cholic acid) through flexible L-lysine spacers, was prepared at the air-water interface.
As confirmed by surface pressure (π)-molecular area (A) isotherms, transition between open conformation and cavity conformation
of the SC(OH) molecule was reversibly induced upon repeated compression and expansion of its monolayer at pH 11 where amino
groups of the lysine residues are not fully deprotonated. Capture and release of an aqueous fluorescent guest (TNS) by SC(OH)
was observed upon dynamic cavity formation through surface fluorescence spectroscopy. At pH 12, dynamic cavity formation of
SC(OH) was sufficiently suppressed, and the capture and release of an aqueous TNS by the monolayer was not virtually observed.
Lessened electrostatic repulsion between the SC(OH) molecules due to conversion of ammonium to free amine may prevent the
cavity from reopening. The importance of dynamic nature of cavity formation on the guest binding was also proved by control
experiments using SC(H), which cannot form cavity conformation at any surface pressures at both pH 11 and 12. 相似文献
10.
Yukiko Hirano Ilde Guedes Marcus Grimsditch Chun-Keung Loong Nobuyoshi Wakabayashi Lynn A. Boatner 《Journal of the American Ceramic Society》2002,85(4):1001-1003
The room-temperature elastic constants of ErVO4 were considerably smaller than those of isostructural silicate and phosphate analogs. The generally "less-rigid" crystalline lattice and weaker metal-oxygen bond-strength in the RVO4 (R = rare earth elements) phases indicates that these materials are of interest for potential applications as an interphase component in toughened oxide ceramic composites. 相似文献