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111.
Muhammad Mustafa Hussain Ed Labelle Gabe Gebara Naim Moumen 《Microelectronic Engineering》2007,84(4):594-598
International Technology Roadmap for Semiconductors 2003 projected nano-imprint lithography has the potential of high throughput, sub-20 nm resolution, and low cost [S.Y. Chou, P.R. Krauss, P.J. Renstrom, Appl. Phys. Lett. 67 (1995) 3144; Science 272 (1996) 85, J.A. Rogers, C. Mirkin, Mater. Res. Bull. 26 (2001)]. For nano-imprint lithography, a template with 1X resolution is required. The existing industrial infrastructure for supporting deep ultra violet 4X photo masks by e-beam and/or a laser beam scanning writer does not offer pitch (center-to-center distance of an array of patterned lines) less than ∼60 nm [<http://public.itrs.net/2003ITRS>]. For nano-imprint lithography to be accepted across the industry, a reproducible simple fabrication process to make a high resolution, single emboss template is essential [L. Jay Guo, J. Phys. D: Appl. Phys. 37 (2004) R123-R141]. Here we show, a general fabrication method and fabricated nano-imprint templates with sub-15 nm template line width and 10 nm pitch length through out the entire 200 mm wafer, varying the deposition thickness of multiple alternate films, using atomic layer deposition. Although multilayer nano-imprint templates and their exciting use have been demonstrated, [W.J. Dauksher et al., J. Vac. Sci. Technol. B 22 (2004) 3306, B. Heidari, et al., The 49th international conference on electron, ion and photon beam technology and nanofabrication, Orlando, Florida, 2005, William M. Tong, et al., Proc. SPIE 5751 (2005) 46-55, N.A. Melosh, A. Boukai, F. Diana, B. Gerardot, A. Badolato, P.M. Petroff, J.R. Heath, Science 300 (2003) 112] such a small pitch was not shown and either complex lattice mismatch-based epitaxially grown films or unconventional etch chemistry was used. The bare necessity was a simple and economical fabrication process for a high throughput nano-imprint template. In that context, we have developed a template fabrication process using classical micro-fabrication techniques. Successful use of these techniques made the template fabrication process simple, economical, and expedient. Also a novel technique to provide flexible and accurate alignment for nanowire patterning has been described. In this technique, nanowire patterning is accomplished on the entire wafer with a single impression. Industry level batch-fabrication of our scheme illustrates its reproducibility and manufacturability. We anticipate, this simple, economical and time saving technique will help researchers and developers to perform their experiment on nano-scale feature patterned substrates easily and conveniently. 相似文献
112.
AbstractBig Data Analytics can be a fantastic business opportunity for many organizations. Already organizations are using advanced analytics to streamline production processes, optimize back office activities, market more effectively, and better satisfy customer demand. That said, it goes without saying (as recent headlines can attest) that sometimes enhanced analytics capabilities can introduce risks such as erosion of privacy, overly-intrusive knowledge about customers, etc.Given this dichotomy, making the decision about when, whether, how much, and how to invest in big data analytics initiatives can be a challenge. Invest too soon and you may obviate existing investments or disrupt business activities; invest too late and you may find that competitors gain advantages that make the market landscape asymmetric.This article outlines how and why applying “tried and true” governance principles can help make this decision easier. For those that have formalized governance structures in place, how they might inform the decision an organization makes in this regard – and for those that don’t have a formalized governance program – how they might co-opt some of those principles to help make this decision more approachable. 相似文献
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115.
A Perry N Tarrier R Morriss E McCarthy K Limb 《Canadian Metallurgical Quarterly》1999,318(7177):149-153
OBJECTIVE: To determine the efficacy of teaching patients with bipolar disorder (manic-depressive psychosis) to identify early symptoms of relapse and seek prompt treatment from health services. DESIGN: Single blind randomised controlled trial with matching on four baseline variables using a minimisation algorithm. SETTING: Mental health services in four NHS trusts (one teaching, three non-teaching). SUBJECTS: 69 patients with bipolar disorder who had had a relapse in the previous 12 months. INTERVENTIONS: Seven to 12 individual treatment sessions from a research psychologist plus routine care or routine care alone. MAIN OUTCOME MEASURES: Time to first manic or depressive relapse, number of manic or depressive relapses, and social functioning examined by standardised interviews every six months for 18 months. RESULTS: 25th centile time to first manic relapse in experimental group was 65 weeks compared with 17 weeks in the control group. Event curves of time to first manic relapse significantly differed between experimental and control groups (log rank 7.04, df=1, P=0.008), with significant reductions in the number of manic relapses over 18 months (median difference 30% (95% confidence interval 8% to 52%), P=0.013). The experimental treatment had no effect on time to first relapse or number of relapses with depression, but it significantly improved overall social functioning (mean difference 2.0 (0.7 to 3.2), P=0.003) and employment (mean difference 0.7 (0.1 to 1.3), P=0.030) by 18 months. CONCLUSION: Teaching patients to recognise early symptoms of manic relapse and seek early treatment is associated with important clinical improvements in time to first manic relapse, social functioning, and employment. 相似文献
116.
D'Amico Elizabeth J.; Metrik Jane; McCarthy Denis M.; Frissell Kevin C.; Applebaum Mark; Brown Sandra A. 《Canadian Metallurgical Quarterly》2001,15(4):341
The current study examined binge drinking among high school students over an academic year. Adolescent drinkers (N?=?621; 58% female) were grouped into 4 trajectories: drinkers (35%), increasers (14%), decreasers (16%), and persistent binge drinkers (35%). Prospective analyses indicated several factors that predicted escalation and de-escalation of binge drinking. Increasers were more likely to regularly use alcohol and cigarettes at a younger age than drinkers. Compared with decreasers, persistent binge drinkers reported regular alcohol and marijuana use at younger ages. Lower levels of perceived student drinking appeared to be a protective factor for onset of binge drinking. The results highlight the need to study precursors to the naturally occurring fluctuations in binge drinking and suggest factors that may accentuate the risk of binge drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
Crack-detection techniques, developed for room temperature studies, have been applied to the study of magnetite layers growing on mild steel in NaOH solutions at 573 K and 10 MN/m2 pressure, when subjected to varying tensile or compressive strains. It has been found that these films are extremely resistant to failure in compression but that they crack in tension at strains of 0·05–0·08%.Strains, below those necessary to cause cracking, result in changes in the rate of the electrochemical reactions associated with the oxidation process. 相似文献
118.
Abstract Proper classification and terminology comprise an essential basis for avoiding confusion or imprecision. Classification will assist in recording available data, setting up a global database and developing predictive relationships. In this paper, an attempt to develop a well‐accepted classification of and terminology for food properties is made. The proposed four classes of food properties are: physical and physico‐chemical properties, kinetic properties, sensory properties, and health properties. 相似文献
119.
R Robinson GT McCarthy O Bandmann M Dobbie R Surtees NW Wood 《Canadian Metallurgical Quarterly》1999,66(1):86-89
Traditional Chinese drugs (TCDs) have played a key role for Chinese people in the treatment of diseases since ancient times. The use of TCDs has generated a great amount of information in the past thousand years about the relationship between natural products and the human body. However, up to now, our understanding on the mode of action of the TCD is still limited. Considering that the basic mechanism of all drug function involves the interaction between the drug and biological receptors at the molecular level, we propose to connect TCDs with modern medicine theory through molecular structures. We propose to explain functions of TCDs by using the knowledge developed in modern molecular biology, pharmacology, computer chemistry, and biochemistry. We are working on a computer-aided Chinese drug study that is discussed in this paper. A short introduction on the progress of our research is also given. 相似文献
120.
Four carbohydrate samples extracted from kraft pulps are used as model substrates for studying the mechanism by which xylanase enhances subsequent bleaching of kraft pulp. Fourier transform infrared spectroscopy confirms that small amounts of aromatic molecules, probably lignin, remain associated with these carbohydrate samples. When the extracts are hydrolyzed with xylanase or acid, size exclusion chromatography shows a decrease in the molecular mass of their UV-absorbing constituents, as well as their carbohydrate constituents as determined by pulsed amperometric detection. The results are consistent with the hypothesis that xylanase prebleaching hydrolyzes the xylan portion of lignin-carbohydrate complexes to leave smaller lignin-containing macromolecules in pulp fiber, thus facilitating the removal of lignin components by bleaching chemicals. 相似文献