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排序方式: 共有1284条查询结果,搜索用时 15 毫秒
101.
102.
Selma Yildizhan Dr. Joop van Loon Prof. Dr. Anna Sramkova Manfred Ayasse Prof. Dr. Cristian Arsene Dr. Cindy ten Broeke Stefan Schulz Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(10):1666-1677
Pheromonally yours : The aphrodisiac pheromones of male Cabbage White butterflies were identified. The small butterfly uses the smaller molecule ferrulactone ( 1 ) to enhance its mating success, while the large butterfly uses the larger compound brassicalactone ( 2 ), which is a new natural product. Both compounds are active in combination with hexahydrofarnesylacetone and phytol.
103.
A thin-film resistor out of Ni(80%)Cr(20%) for integration in a standard complementary metal-oxide-semiconductor process with a temperature coefficient of resistance (TCR) below 10 ppm/K was realized by applying a thin Ti layer underneath. The Ti-layer thickness and the temperature and duration of furnace annealing after deposition were optimized in different experiments. The combination of 5-nm Ti + 10-nm NiCr and a 30-min heat treatment at 350degC in a forming gas ambient was found to yield a sheet resistance of about 140 Omega/sq and a TCR of below 10 ppm/K. The long-term drift of the sheet resistance after 1000 h at 200degC was about 0.3%. A transmission electron microscopy analysis was conducted to investigate the structure of the film and a possible change during annealing. An Auger analysis was conducted for film surface analysis. 相似文献
104.
Hürmüs Gürsu Yamur Güner Kamil Burak Dermenci Metin Genten Ahmet Furkan Bulu Umut Savac Servet Turan Yücel ahin 《国际能源研究杂志》2019,43(10):5346-5354
Nowadays, doped graphenes are attracting much interest in the field of Li‐ion batteries since it shows higher specific capacity than widely used graphite. However, synthesis methods of doped graphenes have secondary processes that requires much energy. In this study, in situ synthesis of N‐doped graphene powders by using of cyclic voltammetric method from starting a graphite rod in nitric acid solution has been discussed for the first time in the literature. The N‐including functional groups such as nitro groups, pyrrolic N, and pyridinic N have been selectively prepared as changing scanned potential ranges in cyclic voltammetry. The electrochemical performance as anode material in Li‐ion batteries has also been covered within this study. N‐doped graphene powders have been characterized by electrochemical, spectroscopic, and microscopic methods. According to the X‐ray photoelectron spectroscopy and Raman results, N‐doped graphene powders have approximately 16 to 18 graphene rings in their main structure. The electrochemical analysis of graphene powders synthesized at different potential ranges showed that the highest capacity was obtained 438 mAh/g after 10 cycles by using current density of 50 mA/g at N‐GP4. Furthermore, the sample having higher defect size shows better specific capacity. However, the more stable structure due to oxygen content and less defect size improves the rate capabilities, and thus, the results obtained at high current density indicated that the remaining capacity of N‐GP1 was higher than the others. 相似文献
105.
In this work, sulfur-doped graphene-coated electrodes are prepared by cyclic voltammetry in different potential ranges and different cycles (from 10 to 50) for selective modification of electrodes by different functional groups. The prepared electrodes are characterized by spectroscopic, microscopic and electrochemical methods. In scanning electron microscopic analysis, formation of graphene layers and their porous structure have been determined. Electrochemical impedance spectroscopic and cyclic voltammetric analyses are also used in electrochemical characterization of the electrodes. Then, the prepared sulfur-doped graphene-coated electrodes by using cyclic voltammetry in one-step and low cost are used as electrode materials of supercapacitor for the first time in the literature. Since the mesoporous structure of the electrodes prepared in lower potential ranges increases, specific capacitance of the electrodes increases from 74 to 1833 mF cm−2 with 10 mA cm−2 current density. This result shows that specific capacitances of prepared electrodes are higher than those of the electrodes prepared with metal-doped in the literature. 相似文献
106.
AD Blaufox WW Lai L Lopez K Nguyen RB Griepp IA Parness 《Canadian Metallurgical Quarterly》1998,82(9):1138-40, A10
Patients with left ventricular hypoplasia and left-sided heart obstructive lesions other than critical aortic stenosis may be inappropriately subjected to single ventricular repair because their assessment is based on faulty qualitative evaluations or on quantitative methods developed for critical aortic stenosis. Patients with left ventricular hypoplasia and left-sided heart obstructions other than critical aortic stenosis successfully underwent biventricular repair despite "failing" to pass established criteria for critical aortic stenosis. 相似文献
107.
108.
NN Biswas SJ Ting MC Mattingly JM Bishop NM Cason VP Kenney RC Ruchti WD Shephard WW Neale PA Elcombe MJ Goodrick JC Hill W Kowald WD Walker P Lucas L Voyvodic R Ammar D Coppage R Davis D Day J Gress S Kanekal N Kwak L Herder J Whitmore RA Lewis BY Oh GA Smith W Toothacker 《Canadian Metallurgical Quarterly》1986,33(11):3167-3171
109.
The mechanism of damage occurring in NaCl contaminated materials has not been clarified yet. Apart from crystallization pressure, other hypotheses have been proposed to explain the cause of decay. Irreversible dilation has been observed in a few cases but has never been studied in a more systematic way. The aim of the research is to contribute to the modeling of this phenomenon.In the present paper the effect of NaCl on the hydric and hygric behavior of a lime-cement mortar is extensively studied. The results indicate that NaCl influences the hydric and hygric dilation behavior of the material. The material contaminated with NaCl shrinks during dissolution and dilates during crystallization of the salt. This dilation is irreversible and sufficient to damage the material after few dissolution/crystallization cycles. This behavior is not restricted to NaCl, but is observed in the presence of other salts as well (NaNO3 and KCl). Outcomes of electron microscopy studies suggest that salts causing irreversible dilation tend to crystallize as layers on the pore wall. 相似文献
110.
HR Franklin GP Simonetti AC Dubbelman WW ten Bokkel Huinink BG Taal G Wigbout IA Mandjes OB Dalesio NK Aaronson 《Canadian Metallurgical Quarterly》1994,5(2):113-117
Human neutrophil PLD activity stimulated with GTP-gamma-S was reconstituted with recombinant ARF1 in cytosol-depleted cells. PMA-pretreatment of intact cells greatly enhanced the subsequent reconstitution of the ARF1-regulated PLD activity. This enhancement was only observed provided that the intact cells were pretreated with PMA, suggesting the stable recruitment of a cytosolic component, presumably protein kinase C, to the membranes. rARF1-reconstituted PLD activity was not dependent on MgATP, but could be considerably enhanced by MgATP. Maximal effects of MgATP were seen at 1 mM. This enhancement by MgATP could not be attributed to protein kinase C. Neomycin was found to inhibit ARF1-regulated PLD activity suggesting the requirement for polyphosphoinositides. We conclude: (i) that many of the observed effects of PMA may be dependent on the presence of the small GTP-binding protein, ARF, and (ii) polyphosphoinositides are required for ARF1-stimulated PLD activity. 相似文献