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101.
双重图形需要更新更苛刻的刻蚀能力,要求低于1.5nm CD均匀性、图形收缩和原位多层刻蚀。 相似文献
102.
Besson Michèle Blackburn Andy Gallezot Pierre Kozynchenko Oleksander Pigamo Anne Tennison Steve 《Topics in Catalysis》2000,13(3):253-257
Carbons derived from phenolic resins were used as catalysts for the aqueous phase oxidation of cyclohexanone at 140°C under
air pressure. The reaction yielded mainly adipic, glutaric and succinic acids. The samples were modified by heat treatments
in CO2, air or N2 at different temperatures and characterized to determine their surface area and porosity and to evaluate the functional groups
on the surface. Treatments under CO2 or air increased the oxidation activity. The selectivity to adipic acid was maximum (33%) after activation in air which greatly
increased the surface concentration of oxygen-containing functional groups. However, it was not possible to attribute the
selectivity to specific acidic, neutral or basic groups present at the surface of carbons.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
103.
全美印艺展(GRAPH EXPO)于10月26~29日在美国芝加哥成功举办。虽然面临着经济不景气,但本次展会则超出了预期,无论是参展商,还是参观者,都满意而归。本期邀请Andy和Julie与您一起感受2008年全美印艺展的气息。 相似文献
104.
The lack of uniformity of analytical techniques employed for quantification of fatty acids led to the successful implementation
of a rapid transesterification method using tetramethylammonium hydroxide to determine and compare the total fatty acid content
of almond, pecan and macadamia oils. Palmitic, oleic and linoleic acids comprised the largest part of the total fatty acid
content in almond and pecan oils. Although oleic acid was also the main constituent of macadamia oil, its concentration was
substantially lower than in the other oils. 相似文献
105.
Bruce Vicki; Ellis Hadyn D.; Gibling Felicity; Young Andy 《Canadian Metallurgical Quarterly》1987,41(4):510
78 undergraduates were asked to rate photographs of faces as male or female and familiar or unfamiliar under a total of 4 conditions in 2 experiments. Results from Exp I indicate that faces whose sex was difficult to classify were no harder to judge as familiar than those whose sex was easy to classify. In Exp II this result was replicated and extended to a situation where the familiarity judgment was contingent on the sex judgment. Findings support the view that analyses of the face's sex and its identity proceed in parallel, rather than in hierarchical, order as claimed by H. Ellis (1986). (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Electrokinetic geosynthetics (EKGs) were developed about a decade ago, producing a material that did not experience the same corrosion problems as metal electrodes when used in electro-osmotic (EO) dewatering applications. The conductive polymeric material from which EKGs are made has the additional advantage of being able to be formed into a variety of shapes, including drainage tubes such as those used in this study. One of the primary concerns regarding EO dewatering applications is the rate of energy consumption. This paper reports experiments at three different scales, on different mine tailings materials, that illustrates the potentially misleading results obtained from small scale laboratory tests. Using large, outdoor tests, power consumption rates for treating a kaolinitic mineral sands tailings and a smectitic diamond tailings were found to be up to 30 times lower than the power consumption rates obtained from laboratory tests using small samples in a purpose built EO cell. The primary reason for the improved performance is thought to be the lower voltage gradient used in the field tests, plus the geometric advantages offered by a field layout where a greater volume of material is exposed to the EO effect than only the material directly between the electrodes, which is the case in the EO cell tests. Finally, in the field tests the EO treatment caused the early development of vertical cracks in the tailings, resulting in increased exposure of the tailings to the effects of solar drying. This effect cannot obviously be reproduced in the EO cell laboratory tests, and can be a major advantage for the in situ treatment of mine tailings lagoons, where in some materials the onset of cracking is significantly delayed by the development of an impermeable surface crust. 相似文献
107.
Andy Norton 《电子元器件资讯》2010,(7)
下一代网络架构是以10千兆以太网成熟发展和工业面向40千兆及100千兆发展为兴起的.聚集的网络为可升级的开放平台处理数据流创造了新挑战.在聚集的下一代架构基础中,常见部件包括高性能的兆兆位转换和在应用层持续增长的复杂性和迅速成长的应用中能够处理几十千兆数据流的可编程的内容处理器.CloudShield已经设计出新的一系列可编程数据包处理器,能够检验、分类,调试和复制数据包,集成与应用层的动态交互. 相似文献
108.
Abedin MJ Cresser MS Meharg AA Feldmann J Cotter-Howells J 《Environmental science & technology》2002,36(5):962-968
The use of arsenic (As) contaminated groundwater for irrigation of crops has resulted in elevated concentrations of arsenic in agricultural soils in Bangladesh, West Bengal (India), and elsewhere. Paddy rice (Oryza sativa L.) is the main agricultural crop grown in the arsenic-affected areas of Bangladesh. There is, therefore, concern regarding accumulation of arsenic in rice grown those soils. A greenhouse study was conducted to examine the effects of arsenic-contaminated irrigation water on the growth of rice and uptake and speciation of arsenic. Treatments of the greenhouse experiment consisted of two phosphate doses and seven different arsenate concentrations ranging from 0 to 8 mg of As L(-1) applied regularly throughout the 170-day post-transplantation growing period until plants were ready for harvesting. Increasing the concentration of arsenate in irrigation water significantly decreased plant height, grain yield, the number of filled grains, grain weight, and root biomass, while the arsenic concentrations in root, straw, and rice husk increased significantly. Concentrations of arsenic in rice grain did not exceed the food hygiene concentration limit (1.0 mg of As kg(-1) dry weight). The concentrations of arsenic in rice straw (up to 91.8 mg kg(-1) for the highest As treatment) were of the same order of magnitude as root arsenic concentrations (up to 107.5 mg kg(-1)), suggesting that arsenic can be readily translocated to the shoot. While not covered by food hygiene regulations, rice straw is used as cattle feed in many countries including Bangladesh. The high arsenic concentrations may have the potential for adverse health effects on the cattle and an increase of arsenic exposure in humans via the plant-animal-human pathway. Arsenic concentrations in rice plant parts except husk were not affected by application of phosphate. As the concentration of arsenic in the rice grain was low, arsenic speciation was performed only on rice straw to predict the risk associated with feeding contaminated straw to the cattle. Speciation of arsenic in tissues (using HPLC-ICP-MS) revealed that the predominant species present in straw was arsenate followed by arsenite and dimethylarsinic acid (DMAA). As DMAA is only present at low concentrations, it is unlikely this will greatly alter the toxicity of arsenic present in rice. 相似文献
109.
110.
Andy LeungJames Wiltshire Anton BlencoweQiang Fu David H. SolomonGreg G. Qiao 《Minerals Engineering》2011,24(5):449-454
Copolymers of acrylamide and vinylpyrrolidinone with varying compositions have been synthesised and employed to depress talc in a model flotation system with process plant operation conditions. Adsorption isotherms indicated that the hydrophilic acrylamide homopolymer has a very low affinity for the hydrophobic talc surface, whereas vinylpyrrolidinone homopolymer strongly adsorbs onto the talc surface. Micro-flotation experiments revealed that the copolymer system can induce stronger talc depression than the homopolymer variants, with the most effective copolymer depressant having 25-30% vinylpyrrolidinone incorporation. The copolymer system is observed to have inherited the strong talc affinity of vinylpyrrolidinone polymer and the strong hydrophilic property from polyacrylamide. This combined effect facilitates the desired strong talc depression in single mineral flotation. However, this copolymer system has similar adsorption affinity on both the talc and pentlandite, hence depressing both talc and pentlandite in the mixed mineral flotation system. This research shows that a sufficient hydrophobic balance on the polymer is necessary for the adsorption and subsequent depression for talc. However, polymer with high adsorption selectivity is required to be a successful synthetic talc depressant for mixed mineral system. 相似文献