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131.
Art Porter 《电子设计技术》2004,11(8):54-58
你进行串行数据分析时所需的实时示波器内存大小取决于你想完成的作业.检查几项常见的验证与故障排除任务有助于确定你需要多大内存. 相似文献
132.
Vincent Consonni Sébastien Renet Jér?me Garnier Patrice Gergaud Lluis Artús Jér?me Michallon Laetitia Rapenne Estelle Appert Anne Kaminski-Cachopo 《Nanoscale research letters》2014,9(1):222
CdTe is an important compound semiconductor for solar cells, and its use in nanowire-based heterostructures may become a critical requirement, owing to the potential scarcity of tellurium. The effects of the CdCl2 heat treatment are investigated on the physical properties of vertically aligned ZnO/CdTe core-shell nanowire arrays grown by combining chemical bath deposition with close space sublimation. It is found that recrystallization phenomena are induced by the CdCl2 heat treatment in the CdTe shell composed of nanograins: its crystallinity is improved while grain growth and texture randomization occur. The presence of a tellurium crystalline phase that may decorate grain boundaries is also revealed. The CdCl2 heat treatment further favors the chlorine doping of the CdTe shell with the formation of chlorine A-centers and can result in the passivation of grain boundaries. The absorption properties of ZnO/CdTe core-shell nanowire arrays are highly efficient, and more than 80% of the incident light can be absorbed in the spectral range of the solar irradiance. The resulting photovoltaic properties of solar cells made from ZnO/CdTe core-shell nanowire arrays covered with CuSCN/Au back-side contact are also improved after the CdCl2 heat treatment. However, recombination and trap phenomena are expected to operate, and the collection of the holes that are mainly photo-generated in the CdTe shell from the CuSCN/Au back-side contact is presumably identified as the main critical point in these solar cells. 相似文献
133.
In the worldwide market we found strongly positioned two thermosetting materials for ophthalmic lenses: CR-39 and Superfin. In this work, the fracture behaviour of both materials is studied through the application of Linear Elastic Fracture Mechanics (LEFM) using two geometries: double torsion and three point bending. The fracture toughness has been determined by the double torsion technique. CR-39 showed a continuous and stable crack propagation, whereas Superfin exhibited a stick-slip behaviour whose instability decreased when the strain rate increased. The values at crack initiation agreed with the fracture toughness results of single edge notched tests in bending geometry. 相似文献
134.
This study examined the impact of using inmate observers for suicide watch within a federal correctional-mental health setting. Results indicate a significant decrease in the mean number of hours inmates remained on suicide watch ( p = .036) following the implementation of the Inmate Observer Program (IOP). Overall, suicidal inmates with a diagnosis of psychotic disorder remained on suicide watch significantly longer ( p = .004) than did inmates in other diagnostic groups. The psychotic group, however, had a significant decrease in mean hours on suicide watch ( p = .001) following the implementation of the IOP. Also, individuals with personality disorders had significantly fewer watches ( p = .033) when inmate observers were used. Initial findings suggest that the use of inmate observers reduces the length of time that suicidal peers remain on watch without compromising standard of care. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
The effects of different organic acid solutions on enzymatic browning of “Baby” lettuce and “Geante Maraichiere” endive were assayed by quantitative measurement of colour changes. Acetic, formic, propionic, malonic, oxalic and lactic acid solutions (10 g l–1) were the most effective at preventing discoloration in stem discs taken from the vegetables. Among the above treatments, acetic, propionic, malonic and oxalic acid solutions (50 g l–1) were selected and applied with the help of cotton wool to the butt end of lettuce and endive heads. The browning process was evaluated during 7 days of storage at 2°C, plus an additional commercial handling period of 2 days at 13°C. Acetic and propionic acid treatments were the most effective at reducing lettuce-butt discoloration during storage and commercial handling. In general, treatments with organic acid solutions were less effective on endive than on lettuce. 相似文献
136.
色彩的视觉感应与包装的色彩效果 总被引:1,自引:0,他引:1
通过对色彩的特性、功能、情感、民俗性分析,论述了色彩对人们视觉刺激的心理感应作用,及商品包装色彩设计的表现手法和视感特征。 相似文献
137.
David Torréns‐Martín Lucia Fernández‐Carrasco Sagrario Martínez‐Ramírez Jordi Ibáñez Lluis Artús Thomas Matschei 《Journal of the American Ceramic Society》2013,96(11):3589-3595
Recent investigations have revealed the great potential of Raman spectroscopy for the characterization of clinker minerals and commercial Portland cements. The usefulness of this technique for the identification of anhydrous, hydrated, and carbonated phases in cement‐based materials has been demonstrated. In the present work, the application of micro‐Raman spectroscopy for the characterization of the main clinker phases of calcium aluminate cements and calcium sulfoaluminate cement is explored. The main stable hydrated phases as well as several important carbonated phases are investigated. Raman measurements on the following phases are reported: (i) pure, unhydrated phases: CA, C12A7, CA2, C2AS, cubic‐C3A, C4AF, and C4A3; (ii) hydrated phases: ettringite, monosulfoaluminate, and hydrogarnet (C3AH6); (iii) carboaluminate phases: hemicarboaluminate and monocarboaluminate. The present results, which are discussed in terms of the internal vibrational modes of the aluminate, carbonate, and sulfate molecular groups as well as stretching O–H vibrations, show the ability of Raman spectroscopy to identify the main hydrated and unhydrated phases in the aluminate and sulfoaluminate cements. The Raman spectra obtained in this work provide an extended database to the existing data published in the literature. 相似文献
138.
The effects of storage temperature, oxygen permeability of packaging material and variety on oxidative stability of vacuum-packaged walnut kernels were studied over a 12 months storage period. The oxidation experiments applied to two popular walnut varieties (Yalova-1 and Yalova-3) grown in Turkey. The peroxide values and hexanal contents of walnut samples significantly increased (p < 0.01) during storage at 30 °C. The highest hexanal content (4464.5–6406.9 μg/kg) were observed in Yalova-3 variety stored at 30 °C for 12 months in Polyamide/Polyethylene film pouches (oxygen permeability: 63.4 ± 0.4 mL/m2/24 h (23 °C)) with 90 μm total thickness. The effect of storage temperature and variety on lipid oxidation was found to be higher than the effect of oxygen permeability of the packaging material. It was concluded that for vacuum-packed walnut kernels in PA/PE film pouches having 63.4 ± 0.4 mL/m2/24 h (23 °C) oxygen permeability, 20 °C is sufficient to protect against oxidation for 12 months. 相似文献
139.
本文简述了几种从AUTO CAD2000至PHOTOSHOP6.0的图形转换方法,并分析了这几种方法的优点和缺点。 相似文献
140.
Ultrasonic degradation of Basic Red 29 (BR29) textile dye in the presence of Co2+-H2O2 system was investigated in this study. The effects of presence of ultrasonic power, concentrations of cobalt (II) acetate (Co(II)Act) and H2O2, temperature and initial pH on the BR29 degradation were examined. Initial dye concentration of 20 mg/L BR29 was used in the study as a model solution. In sonication experiments, an ultrasonic bath at a frequency of 40 kHz was employed. Best experimental conditions were also obtained in the studies as follows: 1000 mg/L Co(II)Act, 1000 mg/L H2O2, 40 °C and original pH of 6.70.According to the results, after 30 min of sonication in the presence of Co2+-H2O2 dye removal efficiency of practically 100% was achieved. It was also found that US enhanced the degradation rate of BR29. 相似文献