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61.
Tunable Spectrum Selectivity for Multiphoton Absorption with Enhanced Visible Light Trapping in ZnO Nanorods
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Kok Hong Tan Fang Sheng Lim Alfred Zhen Yang Toh Xia‐Xi Zheng Chang Fu Dee Burhanuddin Yeop Majlis Siang‐Piao Chai Wei Sea Chang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(20)
Observation of visible light trapping in zinc oxide (ZnO) nanorods (NRs) correlated to the optical and photoelectrochemical properties is reported. In this study, ZnO NR diameter and c‐axis length respond primarily at two different regions, UV and visible light, respectively. ZnO NR diameter exhibits UV absorption where large ZnO NR diameter area increases light absorption ability leading to high efficient electron–hole pair separation. On the other hand, ZnO NR c‐axis length has a dominant effect in visible light resulting from a multiphoton absorption mechanism due to light reflection and trapping behavior in the free space between adjacent ZnO NRs. Furthermore, oxygen vacancies and defects in ZnO NRs are associated with the broad visible emission band of different energy levels also highlighting the possibility of the multiphoton absorption mechanism. It is demonstrated that the minimum average of ZnO NR c‐axis length must satisfy the linear regression model of Z p,min = 6.31d to initiate the multiphoton absorption mechanism under visible light. This work indicates the broadening of absorption spectrum from UV to visible light region by incorporating a controllable diameter and c‐axis length on vertically aligned ZnO NRs, which is important in optimizing the design and functionality of electronic devices based on light absorption mechanism. 相似文献
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63.
Alfred A. Christy 《Lipids》2010,45(8):733-741
Isomers of conjugated linoleic acid from 7t9c through 12t14t can be induced by thermal treatment of triacylglycerol samples
of 9c11t or 10t12c fatty acids in glass tubes. The formation of conjugated linoleic acids (CLAs) has been observed during
thermal induction of the above-mentioned triacylglycerols at 250, 280 and 320°C. The concentrations of isomers formed in the
mixture varied depending on the temperature and duration of the heating experiments. The objective of this study was to find
a suitable thermal induction temperature and time that can produce most of the isomers of CLAs from the above-mentioned triacylglycerols.
Such a mixture would give researchers a reference standard that can be used in the identification of CLAs in GC analyses of
relevant samples. Fifteen-microlitre portions of the triacylglycerol samples containing 9c11t/10t12c fatty acid were placed
in micro-glass ampoules, sealed under nitrogen and then subjected to thermal treatment. The glass ampoules were removed at
regular time intervals, cut open, and part of the samples was analysed by infrared spectroscopy using attenuated internal
reflectance technique. The remainder of the samples was subjected to derivatisation into their methyl esters. The methyl esters
of the isomerised fatty acids were then analysed by gas chromatography after appropriate dilution in heptane. The results
show that the thermally induced glyceride samples of 9c11t/10t12c fatty acids gave CLA profiles containing isomers ranging
from 7t9c to 12t14t. However, the concentrations of the isomers are different depending on the duration of the thermal induction.
It appears that [1,5] sigmatropic rearrangements and positional isomerisations take place in the heated mixtures. The rearrangements
and positional isomerisations are accelerated by increasing temperature. The glyceride samples heated to 325°C form isomers
within 30 min and provide a mixture of CLA isomers that can be used as reference sample containing the methyl esters of CLAs. 相似文献
64.
A direct numerical inversion method for the determination of the refractive index and the thickness of the outermost layer of a thin transparent film on top of a multilayer has been developed. This method is based on a second-order Taylor decomposition of the coefficients of the Abelès matrices of the newly grown layer. The variations of the real-time spectroscopic ellipsometry data are expressed as polynomial fuctions depending on the dielectric constant and the thickness of the newly grown layer. The method is fast, capable of single-wavelength and multiwavelength inversion of continuous as well as discontinuous-index profiles, and can be adapted to many different polarimetric instruments. 相似文献
65.
66.
By a strategy suggested by E. H. Uhlenhuth et al (1983), Diagnostic and Statistical Manual of Mental Disorders (DSM-III) referenced syndrome classifications were derived on the basis of the Hopkins Symptoms Checklist—42 scores of 1,131 elderly community residents. Overall syndrome prevalence rates were consistent with other epidemiologic data: 3.9% for depression, 1.0% for agoraphobia-panic, 2.6% for other phobia, and 6.9% for anxiety. Prevalence rates reflected expected sex differences and showed an age trend for other phobias. Considerable comorbidity among syndromes was observed. The association of the syndromes with patterns of psychosocial risk factors, prior diagnoses, and medication suggests that some but not all of the identified syndromes reflect clinically relevant classifications. If further developed, syndrome classifications based on self-report scales can provide inexpensive and clinically relevant measures of caseness. Required refinements of this approach are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Alfred Lorn Norman 《Computational Economics》1994,7(1):1-21
Herbert Simon advocates that economists should study procedureal rationality instead of substantive rationality. One approach for studying procedural rationality is to consider algorithmic representations of procedures, which can then be studied using the concepts of computability and complexity. For some time, game theorists have considered the issue of computability and have employed automata to study bounded rationality. Outside game theory very little research has been performed. Very simple examples of the traditional economic optimization models can require transfinite computations. The impact of procedural rationality on economics depends on the computational resources available to economic agents. 相似文献
68.
Solid state electronic ballasts promise significant energy savings in the lighting systems of large buildings. However, organizational factors and standard operating procedures may inhibit the adoption of this technology in the large, bureaucratic public and private sector organizations which represent the major potential users of this technology. 相似文献
69.
Schrifttumsübersicht über die beteiligten Randsysteme. Klärung der Frage, welche Fassung des Zustandsschaubildes Eisen(II)-oxid–Tonerde zutreffend ist, mit Hilfe von Schmelzen im Tonerdetiegel. Ermittlung des Schmelzpunktes des Hercynits. Sättigungsisothermen eisen(II)-oxidreicher Schlacken an Hercynit. Untersuchung des quasibinären Schnittes Hercynit–Chromit mit Röntgenfeinstruktur- und Mikrosondenmessungen. Entwurf des Zustandsschaubildes FeO–Cr2O3–Al2O3. 相似文献
70.
Tested the hypothesis that given sustained exposure to aversive maternal control, the male child tends to adapt by 1 of 2 coping styles: (a) a closed style involving social avoidance and narrowed attention to evaluative cues, and (b) an open style embracing manipulative social approach and heightened attention to evaluative cues. 49 experimentally defined closed style and open style aversive-control male undergraduates were compared in their ability to recognize briefly exposed evaluative words. The closed style group correctly identified fewer words than the open style group as predicted. Incorrectly identified words reflected a tendency toward evaluative self-enhancement for both groups. Control comparisons revealed neither difference. Some promising relations between coping styles, breadth of attention to evaluative cues, and paranoid behavior are noted. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献