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71.
Montcalm C Grabner RF Hudyma RM Schmidt MA Spiller E Walton CC Wedowski M Folta JA 《Applied optics》2002,41(16):3262-3269
We present our results of coating a first set of optical elements for an extreme-ultraviolet (EUV) lithography system. The optics were coated with Mo-Si multilayer mirrors by dc magnetron sputtering and characterized by synchrotron radiation. Near-normal incidence reflectances above 65% were achieved at 13.35 nm. The run-to-run reproducibility of the reflectance peak wavelength was maintained to within 0.4%, and the thickness uniformity (or gradient) was controlled to within +/-0.05% peak to valley, exceeding the prescribed specification. The deposition technique used for this study is an enabling technology for EUV lithography, making it possible to fabricate multilayer-coated optics to accuracies commensurate with atomic dimensions. 相似文献
72.
Repokari Leena; Punam?ki Raija-Leena; Poikkeus Piia; Tiitinen Aila; Vilska Sirpa; Unkila-Kallio Leila; Sinkkonen Jari; Almqvist Frederick; Tulppala Maija 《Canadian Metallurgical Quarterly》2006,20(4):670
In this prospective controlled study, the authors examined (a) parenting experiences among couples with successful assisted reproduction treatment (ART; n = 367) and fertile spontaneously conceiving controls (n = 371) and (b) the impact of ante- and perinatal factors and child characteristics on parenting experiences. The results show that positive mothering experiences increased more during the 1st year of parenting and were generally higher among ART mothers than control mothers. No differences were found between ART fathers and controls in their fathering experience. Unpleasant birth experiences, low birth weight, and difficulty soothing the child were associated with high levels of parental stress in the control group, but this was not so among the ART parents. Psychosocial interventions in maternal care should take into account the various meanings that couples give to the history of infertility and conception and ante- and perinatal experiences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
74.
Butler Stephen F.; Newman Frederick L.; Cacciola John S.; Frank Arlene; Budman Simon H.; McLellan A. Thomas; Ford Sabrina; Blaine Jack; Gastfriend David; Moras Karla; Salloum Ihsan M.; Barber Jacques P. 《Canadian Metallurgical Quarterly》1998,10(4):399
The Addiction Severity Index (ASI) is a reliable and valid measure of problem severity among addicted patients. Concerns have been raised about the reliability of the Interviewer Severity Rating (ISR), a summary score for each of 7 domains. As part of an effort to build a computer-administered ASI, regression equations were developed to predict the ISR. Repeated resampling of a large dataset, consisting of 1,124 ASIs conducted by trained interviewers, permitted derivation of stable regression equations predicting the ISR for each ASI domain from patients' answers to preselected interview items. The resulting 7 Predicted Severity Ratings (PSRs) were tested on 8, standardized vignettes, with "gold standard," expert-generated ISRs. Reliabilities compared well with those of intensively trained interviewers. The PSRs could provide an alternative to potentially unreliable interviewer ratings, enhancing the ASI's role in treatment planning and treatment matching and make possible a computer-administered version of the ASI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Smith Timothy W.; Pope Mary K.; Rhodewalt Frederick; Poulton James L. 《Canadian Metallurgical Quarterly》1989,56(4):640
Found in two studies that the Life Orientation Test (LOT) had limited discriminant validity relative to measures of neuroticism. Furthermore, although previous correlations of the LOT with measures of symptom reports and coping behaviors were replicated, these correlations were eliminated when neuroticism was controlled. In contrast, the correlations of symptoms and coping with neuroticism remained significant when LOT scores were controlled. Thus, the LOT is virtually indistinguishable from measures of neuroticism, and previously reported findings using this scale are perhaps more parsimoniously interpreted as reflecting neuroticism rather than optimism. These findings are discussed in terms of existing support for models of optimism and self-control and general methodological issues in studies of personality and health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Alain Burr François Hild Frederick A. Leckie 《Materials Science and Engineering: A》1998,250(2):256-263
In this paper, a constitutive law is presented to model the mechanical behaviour of ceramic matrix composites. It allows matrix-cracking, interfacial debonding, sliding and wear to be accounted for in the framework of continuum mechanics. Based upon micromechanical studies, a 1D and 2D model was derived. An application was performed on a [0,90] SiC/SiC composite. 相似文献
77.
78.
John P. Ranieri Frederick S. Lauten Donald H. Avery 《Journal of Electronic Materials》1995,24(10):1419-1423
The aspect ratio (joint area/joint thickness) of thin (0.001-0.006 in.) surface mount solder (60S-40Pb) joints plays an important
role in determining the mechanical properties and fracture behavior of the joints. This study demon-strates that plastic constraint
of a large aspect ratio 60Sn-40Pb solder joint can develop triaxial (hydrostatic) stresses several times greater than the
average tensile strength of the bulk solder material. A four to sixfold increase in average joint stress and up to a tenfold
increase in peak stress was measured on joints with aspect ratios ranging from 400 to 1000. Although a direct relationship
of the aspect ratio to the average tensile stress is shown, as the Friction Hill model predicts, the observed stress increase
is not nearly as high but proportional to the classical prediction. This is attributed to the existence of internal defects
(oxide particles and micro-voids) and transverse grain boundaries which fail producing internal free surfaces. Thus, the actual
aspect ratio is thickness/d2, where d equals the distance between internal surfaces. The fracture of these constrained joints was brittle, with the separation
occurring between a tin-rich copper tin intermetallic at the interface and the solder matrix. Voids within the solder joint
are shown to relieve the plastic constraint and lower the average tensile stress of the joint. The Friction Hill model may
play an important role in explaining the small percentage of atypical solder joint failures which sometimes occur on electronic
assemblies. In particular, the sudden failure of a thin joint in a strain controlled environment may be attributed to the
development of a large hydrostatic stress component. Therefore, a flaw free, plastically constrained joint which develops
a high stress state will be a high risk candidate for failure. 相似文献
79.
80.
Ss discussed topics with an interviewer (I) whose comments were controlled by a motor response made by S. In Exp. I, there was less increase in silence over trials, more negative attitude toward the I, and longer delay after I responses when these were interpretations rather than reflections. With a choice between interpretation and reflection, several personality differences were found between Ss preferring one rather than the other of the two classes of I response. Ss in Exp. 1 requested an I response less frequently when he disagreed with them, but only under conditions in which Ss were told the I would try to influence them. Under influence instructions there was a positive correlation between frequency of I responses and negative attitude toward him. In Exp. 3, frequency of I response was maintained over trials only for Ss high on the Social Desirability Scale. The attitude of high SD Ss was more negative when emotional, rather than neutral, topics were discussed. (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献