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101.
Lent Robert W.; Hoffman Mary Ann; Hill Clara E.; Treistman Dana; Mount Mandy; Singley Daniel 《Canadian Metallurgical Quarterly》2006,53(4):453
Two versions of a counselor self-efficacy (CSE) measure were administered to 110 prepracticum counselors: a general version, assessing perceived capability to perform basic helping skills and manage the session process with clients generally; and a client-specific version, tapping capability to perform the same behaviors with a specific, current client. Client-specific CSE was found to (a) relate moderately to strongly with general CSE over the course of four counseling sessions, (b) increase significantly over sessions, and (c) account for unique variance in counselors' evaluations of the quality of their sessions. Although it was not a useful direct predictor of clients' session ratings, higher client-specific CSE was associated with greater congruence between counselors' and clients' perceptions of session quality. Implications for further research and training are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Despite suggestibility researchers' focus on adult behaviors that distort children's reports, whether behaviors examined in experimental work are used in the field is unknown. The current study presents a mutually exclusive and exhaustive hierarchical coding system that reflects interview questioning behaviors of concern in experimental work. The study examined 80 unstructured interviews conducted by 41 field interviewers with 40 children ages 3 to 7 about known events. Data on the use of leading and neutral questions are presented and include distinctions between accurate and inaccurate suggested information. In addition, analyses show that interviewers are consistent in their style of questioning and that a preinterview measure of interviewers' preference for a qualitative versus a quantitative interviewing style predicted the introduction of novel information into the interview. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
McGuire John M.; Taylor Dana R.; Broome David H.; Blau Burton I.; Abbott David W. 《Canadian Metallurgical Quarterly》1986,33(3):270
Investigated the role of a group structuring technique developed by G. Egan (1973, 1976) on the amount and depth of process involvement in 2 8-member counseling training groups consisting of graduate students (aged 21–56 yrs). The primary hypothesis was that the structured group would have a higher amount and depth of process involvement scores across time than the no-structure group. Results partly support the conclusion that early structure significantly affects process involvement among group members. Findings also indicate that both groups showed strong gains in depth of process involvement over time. Results are discussed in terms of previous research by R. L. Bednar et al (see record 1974-25973-001) and C. Y. Crews and J. Melnick (see record 1976-21029-001). It is suggested that future research should explore interactions between interpersonal style differences of individual members and various structuring techniques. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Dana Garcia 《乙烯基与添加剂工艺杂志》1997,3(2):126-129
Identifying polymers, additives and contaminants presents unique challenges. Fourier transform infrared spectroscopy (FT-IR) coupled with spectral searching techniques is a very efficient and powerful methodology to answer most identification questions. It is based on the unique IR spectrum characteristic of each compound. This paper outlines procedures employed in the identification of typical PVC formulations, starting with the resin and proceeding to impact modifier, process aids, lubricants, stabilizer system and fillers. The emphasis is on FT-IR microscopy as the most versatile approach requiring small samples and minimal to no sample preparation. Other commonly used FT-IR techniques are also outlined. Wet separation protocols, applicability and limitations as related to FT-IR analysis are discussed. Typical examples include vinyl siding, packaging and bottle formulations as well as contaminants often encountered in these formulations and raw materials. 相似文献
105.
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107.
The utilization of artificial snow for environmentally relevant (photo)chemical studies was systematically investigated. Contaminated snow samples were prepared by various methods: by shock freezing of the aqueous solutions sprayed into liquid nitrogen or inside a large walk-in cold chamber at -35 °C, or by adsorption of gaseous contaminants on the surface of artificially prepared pure or natural urban snow. The specific surface area of artificial snow grains produced in liquid nitrogen was determined using valerophenone photochemistry (400-440 cm(2) g(-1)) to estimate the surface coverage by small hydrophobic organic contaminants. The dynamics of recombination/dissociation (cage effect) of benzyl radical pairs, photochemically produced from 4-methyldibenzyl ketone on the snow surface, was investigated. The initial ketone loading, c = 10(-6)-10(-8) mol kg(-1), only about 1-2 orders of magnitude higher than the contaminant concentrations commonly found in nature, was already well below monolayer coverage. We found that the efficiency of out-of-cage reactions decreased at much higher temperatures than those previously determined for frozen solutions; however, the cage effect was essentially the same no matter what technique of snow production or ketone deposition/uptake was used, including the experiments with collected natural snow. The experimental observation that the contaminant molecules are initially self-associated even at the lowest concentrations was supported by DFT calculations. We conclude that, contrary to frozen aqueous solutions, in which the impurities reside in a 3D cage (micropocket), contaminant molecules located on the artificial snow grain surface at low concentrations can be visualized in terms of a 2D cage. Artificial snow thus represents a readily available study matrix that can be used to emulate the natural chemical processes of trace contaminants occurring in natural snow. 相似文献
108.
Transendothelial electronic resistance (TEER) measurements are performed across a cell layer immobilized on a microfluidic device that also enables the cell layer to interact with a flowing stream of red blood cells (RBCs). A bipolar pulsed square wave potential is applied across a monolayer of bovine pulmonary artery endothelial cells, and the resulting current response is measured and integrated. The overall impedance of the cell layer provides an indicator of cell layer integrity. After cell seeding on the device, a decrease in TEER signal from 22.3 ± 1.6 μC to 3.5 ± 0.4 μC (corresponding to a resistance of 40.9 ± 2.9 Ω·cm(2) to 259.1 ± 27.4 Ω·cm(2)) was observed after 8 h of cell growth. Intracellular nitric oxide (NO) production by the immobilized endothelial cells that had reached confluence was 34% higher than those cells that had not reached confluence, as indicated by the integrated TEER system. Importantly, this NO production by the confluent endothelium was stimulated by ATP released from RBCs flowing under the endothelial cells. In this construct, the described microfluidic device enables both a TEER-based evaluation of cell layer integrity and molecularly communicated interactions of these cells with a flowing stream of blood components. 相似文献
109.
Dana L. Morgan Gerry Triani Mark G. Blackford N. A. Raftery Ray L. Frost Eric R. Waclawik 《Journal of Materials Science》2011,46(2):548-557
In this study, the mechanism of precursor dissolution and the influence of kinetics of dissolution on titanate nanotube formation
were investigated. This comparative study explored the dissolution kinetics for the case of commercial titania powders, one
composed of predominantly anatase (>95%) and the other rutile phase (>93%). These nanoparticle precursors were hydrothermally
reacted in 9 mol L−1 NaOH at 160 °C over a range of reaction times of between 2 and 32 h. The high surface area nanotube-form product was confirmed
using X-ray diffraction, FT-Raman spectroscopy, and transmission electron microscopy. The concentration of nanotubes produced
from the different precursors was established using Rietveld analysis with internal and external corundum standardization
to calibrate the absolute concentrations of the samples. Interpretation of the dissolution process of the precursor materials
indicated that the dissolution of anatase proceeds via a zero-order kinetic process, whereas rutile dissolution is through
a second-order process. The TiO2 nanostructure formation process and mechanism of TiO2 precursor dissolution was confirmed by non-invasive dynamic light scattering measurements. Significant observations are that
nanotube formation occurred over a broad range of hydrothermal treatment conditions and was strongly influenced by the order
of precursor dissolution. 相似文献
110.
A uniqueness type system is used to distinguish values which are referenced at most once from values which may be referenced an arbitrary number of times in a program. Uniqueness type systems are used in the Clean and Mercury programming languages to provide efficiently updatable data-structures and I/O without compromising referential transparency. 相似文献