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1.
O. Smuk P. Nenonen H. Hänninen J. Liimatainen 《Metallurgical and Materials Transactions A》2004,35(7):2103-2109
The microstructures of a powder metallurgy/hot-isostatically pressed super duplex stainless steel, designed and manufactured
for massive components of paper machines, were studied after heat treatments simulating the industrial production. It was
shown that copper precipitates in the ferrite phase as ɛ phase. Morphologically, the copper precipitates are of two types—nearly spherical particles of typical size from 30 to 50
nm, and rodlike particles 30- to 35-nm wide, and up to 700-nm long. The main observations on copper precipitation in modern
super duplex stainless steels are similar to those in low-alloy steels. Copper particles were shown to be the nucleation sites
for the formation of secondary austenite and to pin the boundaries of sigma phase. 相似文献
2.
3.
Maria Saarela Ilkka Virkajrvi Hanna-Leena Alakomi Pia Sigvart-Mattila Jaana Mtt 《International Dairy Journal》2006,16(12):1477-1482
We investigated the stability of differently produced (variables being fermentation time, pH during drying, and cryoprotectant) freeze-dried Bifidobacterium animalis subsp. lactis E-2010 (Bb-12) cells in fruit juice and low-fat milk. In addition, the effect of the food matrix on the acid and bile tolerance of the cells was studied. Cells produced in different ways had comparable stability in milk, whereas in juice, sucrose-protected cells survived better than reconstituted skim milk-protected cells. The acid and bile tolerance was better in cells added to milk compared with those in phosphate buffered saline or juice. Despite good culturable stability in milk the acid and bile tolerance of cells decreased during the storage. Apparently, culturable stability data alone do not give an accurate enough prediction of the probiotic functionality in adverse conditions (e.g. survival in acid and bile stress). When choosing a cryoprotectant for a probiotic also the stability in target food applications should be considered. 相似文献
4.
Jaana Porra 《Information Systems Frontiers》2001,3(1):19-27
In 1996, the author attended a seminar on ethics given by C. West Churchman at the University of California, Berkeley. During that year, the author also interviewed Churchman several times regarding the future direction of information sciences in general and the information systems research field in particular. This article is a compilation of the seminar and the interviews. It is set in the context of both Churchman's earlier and his current views of a global god, good, kindness, and caring. C. West Churchman holds that global ethics should lead to the study and design of information systems to solve large and difficult problems of the humankind such as poverty, crime and disease. His Global Ethical Management (GEM) of information sciences translates into abandoning the current goals and boundaries of the information sciences fields and changing what constitutes valid research to globally ethical endeavors. 相似文献
5.
This paper describes the system dimensioning and the radio network planning methodology for a third generation wcdma system. The applicability of each method is demonstrated using examples of likely system scenarios. The challenges of modeling the multiservice environment are described and the implications to the system performance simulations are introduced. 相似文献
6.
Jaana Porra 《Information Systems Frontiers》2000,1(4):389-399
Today, any doubts about possibilities of significant profits over the Internet are a distant memory. Such has been the proliferation of Internet-based business on the public network. But electronic commerce has turned out to be more difficult to master than previously assumed. For many, ventures have been less lucrative than expected. The problem is that integrating business models with technology is a multifaceted and largely open question (Shaw, et al. 1997). How do businesses of various sizes and industries actually start their Internet activity and how do their business models change over time? More specifically, how do their different Internet strategies play out? This article is the result of a survey of the Internet strategies and business models of 280 companies that sell products and services on the public network. The results show that electronic commerce has penetrated companies of all sizes. Based on this survey it is apparent that while many companies have participated in electronic commerce for years, their business models are still in their infancy stages. 相似文献
7.
Conducted 2 studies to examine negative social reactions from the perspective of rejecting peers. The purpose of Study 1 was to test an attributional model of negative peer reactions in which perceptions of responsibility and specific emotions mediate between deviant peer characteristics and negative social responses. The more children perceived atypical classmates to be responsible for their idiosyncrasies, the more anger and less sympathy they reported. Anger increased rejection and decreased social support, whereas sympathy facilitated social support. In Study 2, the effects of responsibility perceptions and affective reactions (annoyance) on social responses were tested with an experimental design. Perceived responsibility influenced liking and support, whereas annoyance affected sympathy, support, and rejection. The results are discussed with respect to intervention programs that would improve children's social acceptance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
O'Reilly K Pietari J Boehm P 《Environmental science & technology》2011,45(7):3185-6; author reply 3187-8
9.
The present work is an attempt to determine the oil film thickness in a medium-speed four-stroke diesel engine with a cylinder diameter of 200 mm. Experimental research on this topic was found necessary due to the limited amount of published information available with reference to engines of the present size. The experimental part of the study was carried out as firing engine tests, with an instrumented piston, equipped with telemetric data transmission, and an instrumented cylinder liner in a 6-in-line test engine. The study was carried out for different parts of the four-stroke working cycle and for different levels of engine power output. The results were compared with the results of computer simulations, carried out using a commercial software package. The conclusions of the study comprise aspects on the formation and development of the oil film between the rings and the liner under a set of load levels together with the periodical fluctuation during different strokes of the working cycle. 相似文献
10.
Boys from low socioeconomic environments were rated on physical aggression at ages 6, 10, 11, and 12 yrs by teachers and classified according to stability of fighting over time: stable high fighters, high fighters with late onset, desisting high fighters, variable high fighters, and nonfighters. The fighter groups differed from each other both in family background and parenting behavior. They were also significantly associated with delinquency across ages 10 to 14 yrs. A stepwise logistic regression with fighter groups, family adversity index, and parenting behavior variables as predictors showed that the Punishment?×?Fighter Group interaction, together with supervision, predicted self-reported delinquency. The study thus showed that the developmental pathways of physically aggressive behavior for boys in low socioeconomic environments were related to familial adversity and poor parenting, and that they predicted delinquency. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献