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1.
Two groups of 10 speech-language pathology graduate students were each given 7 weeks of singing lessons to determine whether voice lessons could have an effect on their clinical and perceptual skills. Pre-, mid-, and posttests to measure various skills were designed and implemented. With use of paired sample statistical testing, statistically significant results were obtained. In addition, the subjective responses of the students show that the lessons were effective in improving pitch perception, breath control, and legato production or easy onset. This study supports efforts to integrate curricula in vocal performance and speech-language pathology. 相似文献
2.
Englert BC Scholz S Leech PJ Srinivasarao M Bunz UH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(3):995-1000
We describe the synthesis of two cyclobutadiene(cyclopentadienyl)cobalt-containing poly(p-phenylene ethynylene)s (PPEs) and their use as precursors for stable ceramic surface coatings. Organometallic PPEs were shaped into hexagonally ordered assemblies by using the breath-figure method. Such breath figures can be washed away with an appropriate solvent. Upon pyrolysis at 500 degrees C under either nitrogen or air, the bubble arrays persist as ceramics and are insoluble in organic solvents or water. The formed pyrolyzed bubble arrays were analyzed by optical and scanning electron microscopy, as well as energy dispersive X-ray microanalysis (EDX). The composition of the ceramic materials is discussed based on EDX and IR data. 相似文献
3.
Agnieszka Ulanowska Ewa Trawińska Piotr Sawrycki Bogusław Buszewski 《Journal of separation science》2012,35(21):2908-2913
Chemotherapy used as a treatment against lung cancer has influence on metabolic processes occurring in healthy cells. The changes of biochemical pathways proceeded inside cells might be observed in expired air. In the experiment, breath analysis was carried out before and after anticancer therapy. Expired air samples were collected from 22 patients with a biopsy confirmed lung cancer. Volatile organic compounds present in breath were analyzed by gas chromatography/mass spectrometry. For enrichment of analytes solid‐phase microextraction technique was applied. Eight fibers covered by different sorbents were tested. Carboxen‐polydimethylsiloxane fiber revealed the highest extraction efficiency in relation to analytes in breath. The data showed that cytostatic drugs increase the concentration of acetone and isoprene in the breath collected after chemotherapy. Volatile metabolites of administrated drugs were not identified in expired air. 相似文献
4.
《中国光学快报(英文版)》2014,(10):F0003-F0003
Chinese Optics Letters is a short-article journal for the rapid dissemination of new, important results in all branches of optical science and technology and related fields, published monthly by Chinese Laser Press and distributed abroad by the Optical Society (OSA). 相似文献
5.
《物理学报》2014,(23)
<正>Chinese Physics B(Chin.Phys.B),formerly titled Chinese Physics,is an international comprehensive academic journal,aiming to publish original papers and rapid communications reflecting creative and innovative achievements in physics,as well as review papers about important accomplishments in frontier of physics.The journal is published monthly in English by the Chinese Physical Society(CPS)and the IOP Publishing.Chin. 相似文献
6.
《高分子科学》2014,(8)
正Aims and Scope Chinese Journal of Polymer Science(CJPS)is a monthly journal published in English and sponsored by the Chinese Chemical Society and the Institute of Chemistry,Chinese Academy of Sciences.CJPS is edited by a distinguished Editorial Board headed by Professor Fosong Wang and supported by an International Advisory Board in which many famous active polymer scientists all over the world are included.The journal was first published in 1983 under the title 相似文献
7.
The dynamic changes in ferroelectric liquid crystal (FLC) molecular alignments under an applied electric field are examined
by observing the formation of conoscopic figures with a time resolution of 0.1 ms. Close agreements between observed and simulated
conoscopic figures under low voltage (30 V) were obtained. Under high voltage (120 V), however, the observed conoscopic figures
became blurred between 0.8 ms and 1.1 ms after reversal of the electric field. The light scattering producing the blurriness
occurred due to the development of fast transient molecular alignments during the switching transition above the applied voltage
70 V. 相似文献
8.
Honeycomb porous La0.6Sr0.4Co0.2Fe0.8O3−δ-Gd0.2Ce0.8O2−δ (LSCF-GDC) composite cathodes are prepared using the breath figures (BFs) method with nontoxic and easily available water droplets as templates. The fabrication of honeycomb porous membranes is realized in a relatively humid environment, using a volatile solvent. The microstructure and morphology of the membranes produced are investigated by scanning electron microscopy (SEM). The SEM micrographs suggest that experimental conditions, such as ambient temperature, relative humidity, and concentration of polymer and LSCF-GDC powder, which have direct influence on the solvent evaporation affects the pore structure of the porous membranes. Electrochemical impedance spectroscopy (EIS) is used to evaluate the polarization resistance of LSCF-GDC composite cathodes prepared at different experimental conditions. The honeycomb porous LSCF-GDC composite cathode showing average pore diameter of 10 μm illustrates the lowest polarization resistance. 相似文献
9.
Analytical chemistry often involves a large amount of experimental data, and the reliability and accuracy of the experimental results are related to whether the original data can be properly recorded and calculated. In this paper, starting from the importance of significant figures, analyzing the frequently encountered problems related to the significant figures in teaching process, and giving some solutions, we try to help students to learn and master the concept of significant figures, rounding off numerical values, rule of operation and data processing. 相似文献
10.
The formation of ⊥c texture of WS2 thin films by solid state reaction between the spray deposited WO3 and gaseous sulfur vapours with Ni interfacial layer has been reported. X-ray diffraction technique has been used to measure the degree of preferred orientation and texture of WS2 films. Scanning electron microscopy, transmission electron microscopy and atomic force microscopy have been used to characterize the microstructure and morphology. The electronic structure and chemical composition was studied using X-ray photoelectron spectroscopy. The WS2 films comprise single crystalline quality hexagonal crystallites of 15 μm × 15 μm size with their basal planes parallel to the substrate. The film consists of turbostratic stacking sequence of 2H and 3R polytypes of WS2. The tungsten-to-sulfur ratio was estimated to be 1:1.8. The various qualitative models used to explain promotional effects are briefly outlined and the plausible underlying mechanism of formation of ⊥c texture with nickel, in this study, is given. 相似文献