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Wool fabrics were exposed to ultraviolet (UV)–ozone treatment for different periods. After exposure, the fabrics were analyzed by Fourior transform infrared spectroscopy (FTIR). Also, the crystallinity and amorphousity regions were followed by an X‐ray diffraction technique. The results were correlated by mechanical properties measurements. After a certain period of exposure, the dyeability and printability were improved because these abilities are strongly related to the percentage ratio of crystallinity regions to amorphousity regions in wool fabrics. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1469–1476, 2002  相似文献   
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An investigation was made into a reasonable continuous sampling frequency for cardiac Purkinje fiber action potentials. Under the assumption that digital sampling will effectively capture frequency components up to half the sampling rate, action potential records made at 25 kHz were low-pass filtered at various cutoff frequencies. The filtered and unfiltered records were compared by calculating Vmax to determine the effects of progressive loss of high frequency components. It was determined that sampling at 13 kHz is adequate for action potentials with upstroke velocities up to 500 V/sec, and that estimation of Vmax in excess of 800 V/sec is possible.  相似文献   
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A simple, versatile method for non‐covalent functionalization of graphene based on solution‐phase assembly of alkane‐amine layers is presented. Second‐order Møller–Plesset (MP2) perturbation theory on a cluster model (methylamine on pyrene) yields a binding energy of ≈220 meV for the amine–graphene interaction, which is strong enough to enable formation of a stable aminodecane layer at room temperature. Atomistic molecular dynamics simulations on an assembly of 1‐aminodecane molecules indicate that a self‐assembled monolayer can form, with the alkane chains oriented perpendicular to the graphene basal plane. The calculated monolayer height (≈1.7 nm) is in good agreement with atomic force microscopy data acquired for graphene functionalized with 1‐aminodecane, which yield a continuous layer with mean thickness ≈1.7 nm, albeit with some island defects. Raman data also confirm that self‐assembly of alkane‐amines is a non‐covalent process, i.e., it does not perturb the sp2 hybridization of the graphene. Passivation and adsorbate n‐doping of graphene field‐effect devices using 1‐aminodecane, as well as high‐density binding of plasmonic metal nanoparticles and seeded atomic layer deposition of inorganic dielectrics using 1,10‐diaminodecane are also reported.  相似文献   
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In this note prediction intervals for certain functions of the total sample are obtained using a preliminary subsample of the total sample. In some instances these functions pertain to the total test time necessary to complete the experiment. For the simultaneous life test considered by Sobel and Epstein a prediction interval is obtained for the total unit hours of test time necessary to test all of the items as well as a prediction interval for the “remaining life.” In addition the inverse binomial sampling plan discussed by Nadler is considered.  相似文献   
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Medical students at the University of Missouri were taught to search MEDLINE using the Grateful Med software. The traffic files of student searches were analyzed for search behavior. This paper reports on two specific aspects of these analyses: (1) failed searches where retrieval was either too large or too small (zero hits); and (2) a six month follow-up study which focused on error rates and retention of skills. The two major reasons for retrieving too many citations were entering a phrase on a single subject line and a search of only one concept. Of the zero hit searches, the most commonly occurring errors were MeSH (medical subject headings) not used, other MeSH errors, misspelling or keyboard errors, and faulty logic. During the six month follow-up study, the error rates of students declined in spite of the fact that they had not used the software in six months. Furthermore, a larger percentage of the searches showed a more sophisticated use of MeSH than previously employed.  相似文献   
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Objective: The purpose was to develop a short-form version of the Center for Epidemiologic Studies Depression Scale (CES-D) for the identification of persons with major depressive disorder (MDD) within a population with rheumatoid arthritis (RA). Study Design: Data were analyzed from 337 persons with RA. Forty-six participants met the diagnostic criteria for MDD; 291 participants were classified in the non-MDD category (including 21 participants with dysthymia and 18 participants with minor depressive disorder). A short-form version of the CES-D was developed, and multiple cutoff scores were examined. Results: A cutoff score of ≥5 from a 9-item, short-form CES-D was found to be generally as efficient as the more commonly used full-scale cutoff score of ≥16 for classifying participants with MDD within an RA population. Although the shortened CES-D scale (cutoff score ≥5) was slightly more sensitive, it also exhibited slightly less specificity than the full-scale cutoff score of ≥16. Conclusion: The results suggest that a short-form CES-D can be used to screen for MDD within an RA sample with a degree of efficiency that is generally comparable to that of the full-scale instrument. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Patterned bandpass dielectric interference filters with centre wavelengths around 1.3 mu m have been applied to top-entry photodiodes to produce high-speed, high-responsivity, photodetectors for wavelength division multiplexing. The measured responsivity exceeded 25 A/W with a full width half maximum of 19 nm and peak rejection of over 25 dB.<>  相似文献   
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IT爱情观     
莫明 《现代计算机》2009,(11):134-134
斑马和驼鸟的共生现象 无论是斑马还是驼鸟,都算得上是有实力的大型动物,然而为了预防危险,它们依然会结伴去进食。斑马视力超群;驼鸟听力出众,它们一起进食,就能够防范猛兽的突袭。在职场中,即使你是能力超群的人,也一定会有弱点,比如一位擅长战略规划的领导者,可能对于具体的细节实施就比较迟钝。  相似文献   
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