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991.
Aniello Esposito Mauro Ciappa Wolfgang Fichtner 《Microelectronics Reliability》2011,51(9-11):1673-1678
Scanning electron microscopy is still the technique of choice for imaging and for in-line measurement of critical dimensions and overlay accuracy in most of the core technology processes. In particular, critical dimension microscopy provides information about design template matching and edge placement errors through links with design having proven beneficial effects on process yield and product reliability. In this paper, the use of high performance computing is demonstrated to simulate linescans and 2D secondary electron images to be used in optical proximity error correction strategies for nanometer scale technologies. 相似文献
992.
Finke Kathrin; Schwarzkopf Wolfgang; Müller Ulrich; Frodl Thomas; Müller Hermann J.; Schneider Werner X.; Engel Rolf R.; Riedel Michael; M?ller Hans-Jürgen; Hennig-Fast Kristina 《Canadian Metallurgical Quarterly》2011,120(4):890
Attention deficit hyperactivity disorder (ADHD) persists frequently into adulthood. The decomposition of endophenotypes by means of experimental neuro-cognitive assessment has the potential to improve diagnostic assessment, evaluation of treatment response, and disentanglement of genetic and environmental influences. We assessed four parameters of attentional capacity and selectivity derived from simple psychophysical tasks (verbal report of briefly presented letter displays) and based on a “theory of visual attention.” These parameters are mathematically independent, quantitative measures, and previous studies have shown that they are highly sensitive for subtle attention deficits. Potential reductions of attentional capacity, that is, of perceptual processing speed and working memory storage capacity, were assessed with a whole report paradigm. Furthermore, possible pathologies of attentional selectivity, that is, selection of task-relevant information and bias in the spatial distribution of attention, were measured with a partial report paradigm. A group of 30 unmedicated adult ADHD patients and a group of 30 demographically matched healthy controls were tested. ADHD patients showed significant reductions of working memory storage capacity of a moderate to large effect size. Perceptual processing speed, task-based, and spatial selection were unaffected. The results imply a working memory deficit as an important source of behavioral impairments. The theory of visual attention parameter working memory storage capacity might constitute a quantifiable and testable endophenotype of ADHD. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
993.
即将应用到PANDA数据获取系统与触发系统及未来BESⅢ触发系统升级的高性能计算节点[5](HPCN)符合ATCA设计规范,基于IPMI协议的智能平台管理系统为其高可靠性提供保障.自主设计的智能平台管理模块具有丰富的板级管理功能,如Hot Swap和电源分配协调,板上器件状态监控,与机箱控制器的协调通信等.主要介绍了智... 相似文献
994.
Wolfgang Krauss Julia Lorenz Nils Holstein Jürgen Konys 《Fusion Engineering and Design》2011,86(9-11):1607-1610
Tungsten is considered in fusion technology as functional and structural material in the area of blanket and divertor for future application in DEMO. The KIT design of a He-cooled divertor includes joints between W and W-alloys as well as of W with Eurofer-steel. The main challenges range from expansion mismatch problem for tungsten/steel joints over metallurgical reactions with brittle phase formation to crack stopping ability and excellent surface wetting. These requirements were only met partly and insufficiently in the past e.g. by direct Cu-casting of tungsten onto steel.Both, the joining needs and the observed failure scenarios of conventionally joined components initiated the development of improved joining technologies based on electro-chemical processing routes. As electrolytes aqueous and aprotic, water free, system are integrated into this development line. In the first step principle requirements are presented to guarantee a reproducible and adherent deposition of scales based on Ni and Cu acting as inter layers and filler, respectively, to generate a real metallurgical bonding as demonstrate by 1100 °C joining tests. The development field aprotic systems based on ionic liquids is discussed with respect to enable development of refractory metal based fillers with focus high temperature W–W brazing. 相似文献
995.
Susanne Siebentritt Timon Kampschulte Andreas Bauknecht Ulf Blieske Wolfgang Harneit Ulrich Fiedeler Martha Lux-Steiner 《Solar Energy Materials & Solar Cells》2002,70(4):447-457
ZnSe buffer layers for Cu(ln,Ga)Se2/buffer/ZnO solar cells have been prepared by metal organic chemical vapor deposition (MOCVD). Using photoassisted MOCVD, deposition temperatures down to 265°C are possible. It is shown that deposition temperatures well below 300°C are essential as well as deposition times not much longer than 3 min. Higher temperatures and longer deposition times lead to absorber degradation. With optimized buffer deposition efficiencies of 11% have been obtained on CIGS absorbers from the Siemens pilot production line. 相似文献
996.
The following case report describes the implantation of intrastromal corneal ring segments (ICRS) and the postoperative contact lens treatment in a 42-year-old patient with bilateral advanced keratoconus. The patient had a preoperative contact lens intolerance. After femtosecond laser assisted surgery and the implantation of ICRS new custom mini-scleral contact lenses were fitted. The postoperative subjective and objective contact lens tolerance was excellent. 相似文献
997.
Photo-fenton degradation of diclofenac: identification of main intermediates and degradation pathway 总被引:2,自引:0,他引:2
Pérez-Estrada LA Malato S Gernjak W Agüera A Thurman EM Ferrer I Fernández-Alba AR 《Environmental science & technology》2005,39(21):8300-8306
In recent years, the presence of pharmaceuticals in the aquatic environment has been of growing interest. These new contaminants are important because many of them are not degraded under the typical biological treatments applied in the wastewater treatment plants and represent a continuous input into the environment. Thus, compounds such as diclofenac are present in surface waters in all Europe and a crucial need for more enhanced technologies that can reduce its presence in the environment has become evident. In this sense, advanced oxidation processes (AOPs) represent a good choice for the treatment of hazardous nonbiodegradable pollutants. This work deals with the solar photodegradation of diclofenac, an antiinflammatory drug, in aqueous solutions by photo-Fenton reaction. A pilot-scale facility using a compound parabolic collector (CPC) reactor was used for this study. Results obtained show rapid and complete oxidation of diclofenac after 60 min, and total mineralization (disappearance of dissolved organic carbon, DOC) after 100 min of exposure to sunlight. Although diclofenac precipitates during the process at low pH, its degradation takes place in the homogeneous phase governed by a precipitation-redissolution-degradation process. Establishment of the reaction pathway was made possible by a thorough analysis of the reaction mixture identifying the main intermediate products generated. Gas chromatography-mass spectrometry (GC/ MS) and liquid chromatography coupled with time-of-flight mass spectrometry (LC/TOF-MS) were used to identify 18 intermediates, in two tentative degradation routes. The main one was based on the initial hydroxylation of the phenylacetic acid moiety in the C-4 position and subsequent formation of a quinone imine derivative that was the starting point for further multistep degradation involving hydroxylation, decarboxylation, and oxidation reactions. An alternative route was based on the transient preservation of the biphenyl amino moiety that underwent a similar oxidative process of C-N bond cleavage. The proposed degradation route differs from those previously reported involving alternative degradation processes (ozonization, UV/H2O2, or photolysis), indicating that diclofenac degradation follows different pathways, depending on the treatment applied. 相似文献
998.
Carlo C. Peich Wolfgang Seidel Nicole Hanak Rainer Waibel Marc Schneider Monika Pischetsrieder 《European Food Research and Technology》2005,221(1-2):9-13
Sugar degradation products are formed during heat treatment of food as well as endogenously in vivo. As reactive carbonyl compounds, they react readily with proteins or DNA to form protein- or DNA-bound advanced glycation end products (glycation reaction or Maillard reaction). In this study, we investigated the formation of potential DNA–protein cross-link products from sugar degradation products. 2-Deoxyguanosine, l-lysine and different carbohydrates were incubated at 37 °C. The sugar degradation products dihydroxyacetone and d,l-glyceraldehyde lead to the formation of two new cross-link products. The new compounds were isolated by preparative high-performance liquid chromatography and identified by spectral data as the two diastereomers of N6-[2-(N2-2-deoxyguanosyl)propionyl]lysine. In this structure, the -amino group of lysine and the exocyclic amine group of 2-deoxyguanosine are linked via a carboxyethyl group, derived from the carbohydrate component. The binding sites and the binding types were confirmed by synthesis of the analogous products from N2-(1-carboxyethyl)guanosine and N-acetyllysine methyl ester.Dedicated to Professor Th. Severin on the occasion of his 75th birthday 相似文献
999.
Hartmut Rehbein Gabriele Kress Wolfgang Schreiber 《Journal of the science of food and agriculture》1978,29(12):1076-1082
The specific activities of the lysosomal enzymes α-glucosidase and β-N-acetylglucosaminidase were determined in press juices and extracts from fresh and frozen/thawed fillets of cod, saithe, red fish and haddock. For each of the two enzymes it was found that the press juice/extract activity ratio increased following the freezing/thawing process (six to nine times for αglucosidase and three to five times for β-N-acetylglucosaminidase). 相似文献
1000.