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91.
Gianoglio Dario Ciftci Nevaf Armstrong Sarah Uhlenwinkel Volker Battezzati Livio 《Metallurgical and Materials Transactions A》2021,52(9):3750-3758
Metallurgical and Materials Transactions A - Gas atomization is the most used powder production technique since it provides good control on particles shape, surface oxidation and dimension. It is a... 相似文献
92.
3.2.7关于绕线器件(电容、变压器、扼流圈等)的问题
对于绕线(感性)器件,需要从三个方面进行考虑:杂散磁场的控制、特性参数随电流和温度的变化以及电阻特性。 相似文献
93.
(上接2007年第6期91页)
1.6 快速简便的内部测试有助于有源器件的选择
尽管供应商提供了电子器件的EMC性能参数,但在实际工作环境中的EMC性能通常是无法预知的。在设计部门内部可以采取一些简便快捷的EMC测试方法对功能性电路进行测试,但电路中至少要具有时钟、完整的信号或数据输入/输出功能。有些供应商还可提供用于此类测试的评估板。 相似文献
94.
Mitchell R. Armstrong Bohan Shan Joseph Winarta Bin Mu 《American Institute of Chemical Engineers》2020,66(2):e16816
A new class of core–shell adsorbents has been created by electrospun metal–organic framework (MOF) particles embedded in polymer nanofibers, which have provided many unique properties compared to the existing MOF coating technologies. For the first time, we demonstrate the improved adsorption selectivity of CO2 over N2 using electrospun polymer/ZIF-8 adsorbents in experiments. Furthermore, an analytical model based on the assumption that the diffusivity in core is 10 times higher than that in shell is developed to describe the theory of improved selectivity for core–shell adsorbents that is validated against a more accurate finite element model developed in COMSOL. Our model shows three regimes including exclusive shell uptake, linear core uptake, and asymptotic core uptake. These regimes are related to material properties and uptake times, which could be used as design criteria to balance core stability, maximum selectivity, and maximum uptake. An advanced HAADF STEM tomography (Movie S1 ) shows that the shell thickness in the case of polymer/ZIF-8 is on the order of 10 nm, allowing the regime of maximum selectivity to be realized. Kinetically limited adsorption tests at 45°C demonstrate that these composite fibers can perform in a regime of selectivity and uptake for the separation of CO2 and N2 that is unobtainable by either the MOF or fiber independently, showing a great potential for postcombustion CO2 capture. 相似文献
95.
Lopez-Espinosa MJ Fletcher T Armstrong B Genser B Dhatariya K Mondal D Ducatman A Leonardi G 《Environmental science & technology》2011,45(19):8160-8166
Animal studies suggest that perfluorocarbons (PFCs) may alter sexual maturation. Relationships of human PFC exposure with puberty are not clear. We conducted a cross-sectional study to investigate whether perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were associated with indicators of sexual maturation in a 2005-2006 survey of residents with PFOA water contamination from the Mid-Ohio Valley. Participants were 3076 boys and 2931 girls aged 8-18 years. They were classified as having reached puberty based on either hormone levels (total >50 ng/dL and free >5 pg/mL testosterone in boys and estradiol >20 pg/mL in girls) or onset of menarche. We estimated the odds of having reached puberty classified by these criteria and the fitted median age of reaching puberty in relation to serum PFOA and PFOS concentrations measured when puberty status was assigned. For boys, there was a relationship of reduced odds of reached puberty (raised testosterone) with increasing PFOS (delay of 190 days between the highest and lowest quartile). For girls, higher concentrations of PFOA or PFOS were associated with reduced odds of postmenarche (130 and 138 days of delay, respectively). In conclusion, our study showed a later age of puberty in this population correlated with PFC concentrations. 相似文献
96.
97.
98.
Reports an error in "Interpreting the interest–efficacy association from a RIASEC perspective" by Patrick Ian Armstrong and David L. Vogel (Journal of Counseling Psychology, 2009[Jul], Vol 56[3], 392-407). In the article, an incorrect value was reported for the correlation between Artistic and Social occupational interests in Table 1 (p. 400), incorrect values were reported for some of the fit indices presented in Table 2 (p. 402), and incorrect values were reported for the fit indices presented in Table 5 (p. 404). The correct value for the correlation between Artistic and Social occupational interests is r = .44. Attached are the fit indices that are correct for the Structural Equation Models presented in Table 2 and Table 5. (The following abstract of the original article appeared in record 2009-10122-005.) Social cognitive career theory (SCCT) defines self-efficacy as the critical variable that influences the development of career-related beliefs and attitudes, including interest. In comparison, the authors propose that J. L. Holland’s (1997) theory of Realistic, Investigative, Artistic, Social, Enterprising, and Conventional (RIASEC) types can be interpreted as supporting an alternative model in which both interest and self-efficacy are components of an individual’s vocational identity. Meta-analytic research indicates that RIASEC-based measures of interest and self-efficacy are positively correlated, but these results are also interpreted as supporting the distinctness of the two constructs. The present study evaluates links between interest and self-efficacy with occupation- and activity-based measures of interest and self-efficacy. Multidimensional scaling, cluster analysis, and structural equation modeling results suggest that observed correlations between interest and self-efficacy measures can be attributed to shared Holland-type characteristics of the measures. These results support a Holland-based integrated model of individual differences, with both interest and self-efficacy indicators of RIASEC types, thereby raising questions about the ordering of self-efficacy and interest measures in the SCCT model but also highlighting the importance of assessing both constructs in applied settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Allen Daniel N.; Randall Carol; Bello Danielle; Armstrong Christina; Frantom Linda; Cross Chad; Kinney Jefferson 《Canadian Metallurgical Quarterly》2010,24(2):244
Working memory deficits have been identified in bipolar disorder, but there is evidence suggesting that these deficits may be markers for psychosis rather than affective disorder. The current study examined this issue by comparing two groups of individuals with bipolar disorder, one with psychotic features and one without psychotic features, with a group of normal controls. Working memory was conceptualized as a multicomponent system that includes auditory and visuospatial short-term stores, executive control processes, and an episodic buffer that allows for communication between short- and long-term memory stores (Baddeley & Logie, 1999). Results indicated that only executive control processes significantly differentiated the psychotic and nonpsychotic bipolar groups, although visuospatial working memory differentiated both bipolar groups from controls. The results support the idea that some aspects of working memory performance are markers for psychosis, while others may be more general markers for bipolar disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
JA Turpin Y Song JK Inman M Huang A Wallqvist A Maynard DG Covell WG Rice E Appella 《Canadian Metallurgical Quarterly》1999,42(1):67-86
Nucleocapsid p7 protein (NCp7) zinc finger domains of the human immunodeficiency virus type 1 (HIV-1) are being developed as antiviral targets due to their key roles in viral replication and their mutationally nonpermissive nature. On the basis of our experience with symmetrical disulfide benzamides (DIBAs; Rice et al. Science 1995, 270, 1194-1197), we synthesized and evaluated variants of these dimers, including sets of 4,4'- and 3,3'-disubstituted diphenyl sulfones and their monomeric benzisothiazolone derivatives (BITA). BITAs generally exhibited diminished antiviral potency when compared to their disulfide precursors. Novel, monomeric structures were created by linking haloalkanoyl groups to the benzamide ring through -NH-C(=O)- (amide) or -S-C(=O)- (thiolester) bridges. Amide-linked compounds generally lacked antiviral activity, while haloalkanoyl thiolesters and non-halogen-bearing analogues frequently exhibited acceptable antiviral potency, thus establishing thiolester benzamides per se as a new anti-HIV chemotype. Pyridinioalkanoyl thiolesters (PATEs) exhibited superior anti-HIV-1 activity with minimal cellular toxicity and appreciable water solubility. PATEs were shown to preferentially target the NCp7 Zn finger when tested against other molecular targets, thus identifying thiolester benzamides, and PATEs in particular, as novel NCp7 Zn finger inhibitors for in vivo studies. 相似文献