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41.
通过对真丝绸整个产品生命过程的分析,对其进行了生命周期评价,说明了丝绸与其产地环境之间的联系和影响,尝试寻求两者之间的和谐关系,提出了清洁生产工艺的规划和各种行之有效的对策和措施,尝试了对环境友好的丝绸印染工艺的生态设计。 相似文献
42.
An existing extensive database on the isothermal and thermomechanical fatigue behaviour of high-temperature titanium alloy
EVII 834 and dispersoid-strengthened aluminum alloy X8019 in SiC particle-reinforced as well as unreinv conditions was used
to evaluate both the adaptability of fracture mechanics approaches to TMF and the resulting predictive capabilities of determining
material life by crack propagation consideration. Selection of the correct microstructural concepts was emphasised and these
concepts were, then adjusted by using data from independent experiments in order to avoid any sort of fitting. It is shown
that the cyclic /-integral (δJeff concept) is suitable to predict the cyclic lifetime for conditions where the total crack propagation rate is approximately
identical to pure fatigue crack growth velocity. In the case that crack propagation is strongly affected by creep, the creep-fatigue
damage parameter δCF introduced by Riedel can be successfully applied. If environmental effects are very pronounced, the accelerating influence
of corrosion on fatigue crack propagation can no longer implicitly be taken into account in the fatigue crack growth law.
Instead, a linear combination of the crack growth rate contributions from plain fatigue (determined in vacuum) and from environmental
attack is assumed and found to yield a satisfactory prediction, if the relevant corrosion process is taken into account. 相似文献
43.
Ya. Unigovski A. Eliezer E. Abramov Y. Snir E. M. Gutman 《Materials Science and Engineering: A》2003,360(1-2):132-139
Corrosion fatigue tests were carried out on extruded AZ31 (3% Al, 1% Zn, 0.3% Mn, Mg—the rest), AM50 (5% Al, 0.4% Mn, Mg—the rest) and ZK60 (5% Zn, 0.5% Zr, Mg—the rest) Mg alloys in air, NaCl-based and borate solutions. Nsol/Nair ratios (the relative fatigue life) were used for the analysis of the corrosion fatigue behavior of Mg alloys in various environments, where Nsol and Nair are the numbers of cycles to failure in the solution and in air, respectively. Extruded ZK60 alloy reveals very high fatigue and corrosion fatigue properties in comparison with other alloys. However, it has the lowest relative fatigue life (Nsol/Nair 10−3–10−2) or the highest sensitivity to the action of NaCl-based solutions in comparison with that of AM50 and AZ31 alloys (Nsol/Nair 10−2–10−1). Under the same stress, the corrosion fatigue life of extruded alloys is significantly longer than that of die-cast alloys (Nsol for extruded AM50 in NaCl is two to three times longer than that of die-cast AM50). 相似文献
44.
In contrast to D. C. Zuroff, M. Mongrain, and D. A. Santor (2004), the current authors find the promissory note of dependency-sociotropy (DEP-SOC) and self-criticism-autonomy (SC-AUT) as a model of risk for depression to be in default. The authors propose reorganizing what has been cast as unitary effort into 3 distinct endeavors: a psychoanalytic clinical theory, development of a refined empirical model of risk for clinical depression, and research examining the effects of DEP-SOC and SC-AUT on interpersonal relationships in nonclinical samples. The authors identify some issues that need to be accommodated regardless of whether the assessment of Zuroff et al. (2004) or their own is accepted. DEP-SOC and SC-AUT are best construed as correlated, continuous dimensions. Future work also needs to accommodate depression as chronic recurrent condition, advances in developmental psychopathology, and more stringent criteria for positing a risk factor for clinical disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
46.
Behaviors and emotions during specific visits may reveal the interpersonal processes of mother-daughter ties, yet most research uses global assessments of these ties. Forty-eight mother-daughter pairs participated in audiotaped conversations and completed surveys. All mothers were over age 70 and in good health. Daughters tended to take a central role in structuring the conversations. Conversations were characterized by high levels of felt and expressed positive emotions and behaviors for mothers and daughters. Nevertheless, mothers reported more positive and fewer negative emotions, whereas daughters expressed more positive behaviors than did mothers. Mothers' positive feelings and behaviors were associated with daughters'. Finally, mothers' and daughters' emotions and behaviors were associated with their destructive responses to being upset with each other, providing support for the ambivalence perspective of parent-offspring relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
The purpose of this study was to examine predictors and consequences of spouses' involvement in each others' strategies for pursuing important personal goals called life tasks. Husbands and wives within 39 short- and long-term marriages described five life tasks and provided appraisals of whether each was shared with their spouse. Participants later completed 14 consecutive diary entries recording daily life task pursuit strategies, the extent of spouse involvement in each, and measures of positive and negative affect. Results indicated that interdependence in life task appraisals prospectively predicted greater spouse involvement, and greater spouse involvement was associated with more positive affect for that day. Life task appraisals may provide avenues for understanding couples' strategies for dealing with goals or stressors and how those strategies affect mood. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
48.
49.
The environmental and socio‐economic impacts of biomass utilization by co‐firing with brown coal in an existing thermoelectric unit in Greece or through its pure combustion in a new plant were studied and evaluated in this work. The 125 MWe lignite‐fired power plant in Ptolemais Power Station (Western Macedonia) was used as reference system. The environmental benefits of the alternative biomass exploitation options were quantified based on the life cycle assessment methodology, as established by SETAC, while the BIOSEM technique was used to carry out socio‐economic calculations. The obtained results showed clear environmental benefits of both biomass utilization alternatives in comparison with the reference system. In addition, co‐firing biomass with lignite in an existing unit outperforms the combustion of biomass exclusively in a new plant, since it exhibits a better environmental performance and it is a low risk investment with immediate benefits. A biomass combustion unit requires a considerably higher capital investment and its benefits are more evident in the long run. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
50.
A series of polyesters was prepared to evaluate hydrolytic stability as a function of cyclohexyl dibasic acid content. The
three cyclohexyl dibasic acids: 1,2; 1,3; and 1,4 were formulated into polyesters with two glycols. The proportion of cis
and trans isomers was evaluated via 1H NMR. The hydrolytic stability of short chain polyesters was evaluated in an acetone/water mixture which solubilized the
polyesters to mimic oligoester behavior within a thermosetting polyester coating environment. The rate of hydrolysis was monitored
by acid titration and corroborated by GPC. Surprisingly, 1,2-cylohexyl diacid-based polyesters were robust, and 1,3-cyclohexyl
diacid-based polyesters were the most susceptible to hydrolysis. Evidently, a 1,2-anchimeric effect for cyclohexyl dibasic
acid polyesters was not an important consideration, while the 1,3-cyclohexyl ester interaction was. Consequently, an anomeric
effect was proposed.
Presented at the 81st Annual Meeting of the Federation of Societies for Coatings Technology, November 12–14, 2003, in Philadelphia,
PA. 相似文献