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971.
We demonstrate a cavity ringdown spectrometer that affords a frequency resolution higher than the conventional limit imposed by the bandwidth of a pulsed laser source. A Fabry–Perot etalon at the exit of a ringdown cavity disperses the frequency components of a broadband ringdown signal spatially, permitting a narrow-linewidth spectral measurement based on single-exponential decay signals. A proof of principle experiment is presented with the P(9) transition of the [50]_10000 band of C2H2. This technique is expected to be useful for in situ monitoring molecular concentration. 相似文献
972.
Sung Won Youn Ho Kyun Kim Hong Tae Kim Sung Mi Han Jin Kuk Do Young Rok Do Hui Joong Lee Jongmin Lee Jae Hong Lim 《Journal of synchrotron radiation》2014,21(1):215-222
Phase‐contrast synchrotron X‐ray microtomography (pcSyncX) based on the highly coherent X‐ray beam has previously been used to visualize the microstructures of biologic specimens, but it has never been used to evaluate embolic debris adherent on a cerebral protection device (CPD). The purpose of this study was to demonstrate the feasibility of pcSyncX for evaluating embolic debris during carotid artery stenting (CAS). Five patients (four males, age range 67–77 years) with severe carotid artery stenosis underwent CAS. The retrieved CPD was exposed to synchrotron radiation and 1000 pcSyncX projection images were obtained by rotating the CPD through 180°. An X‐ray shadow of a CPD was converted into a visual image by the scintillator. After microtomographic reconstruction, the three‐dimensionally reconstructed images were further segmented into the embolic debris and CPD. The total volume of emboli was calculated by summing the volume at each scanning level. The number of membrane pores covered by emboli as seen from the outer surface was counted and the percentage of covered area was calculated. Embolic debris was clearly demonstrated not only on the inner surface and within pores but also on the outer surface of the CPD. The mean total volume of embolic debris was 0.538 × 10–6 mm3 (range 0.225–0.965 × 10–6 mm3). Most (61.5%) of the debris was located at the apical one‐third of the CPD and 20.8% of the pore area was covered by debris. 相似文献
973.
Won Sang Chung 《International Journal of Theoretical Physics》2014,53(2):426-434
In this paper we propose the new q-oscillator algebra. We discuss the coherent state and the deformed su(2) algebra for this algebra when q is real. As is different from Arik–Coon algebra (J. Math. Phys. 17:524, 1976), this algebra is invariant under the hermitian conjugation for complex q. When q is a root of unity, we obtain the finite dimensional Fock space. Finally we discuss the thermodynamics of particle obeying this algebra when q is a root of unity. 相似文献
974.
Won Sang Chung Taekyun Kim Hyuck In Kwon 《Russian Journal of Mathematical Physics》2014,21(2):156-168
In this paper, we consider the q-analog of the Laplace transform and investigate some properties of the q-Laplace transform. In our investigation, we derive some interesting formulas related to the q-Laplace transform. 相似文献
975.
Kil Sik Min Yoon Jae Kim Hyun Jin Ko Dae Hyun Kwak Tae Wook Kim Jong Won Shin Bong Gon Kim 《Journal of Physical Organic Chemistry》2014,27(12):960-966
We have isolated two isomeric solids 1 and 2 of N,N′‐bis(3,5‐dichlorosalicylidene)‐2,2′‐ethylenedianiline and characterized by IR, UV/Vis, X‐ray powder diffraction, thermogravimetric analysis/differential thermal analysis, and X‐ray crystallography. Although the solids are same formulas, each shows different colors and crystal structures. Orange solid ( 1 ) shows endo conformation while yellow solid ( 2 ) exhibits exo form depending on packing modes. UV/Vis spectra of 1 and 2 appear very similar patterns in the solid state; however, the bands of 1 are slightly red‐shifted compared with those of 2 . 1 displays a strong fluorescent emission band at ~582 nm while 2 shows an intense fluorescent signal at ~563 nm. The charge density populations of 1 and 2 have been studied by computational simulations using density functional theory at pbe1pbe/6‐311G** level. The calculated highest occupied molecular orbital and lowest unoccupied molecular orbital energies of 1 and 2 confirm that charge transfer occurs within the organic molecules. The energy difference of HOMO‐LUMO in 1 is smaller slightly than that of 2 about 0.05 eV (~17 nm). Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
976.
Seon Geun Kim Kyoung Won Jang Wook Jae Yoo Sang Hun Shin Seunghyun Cho Bongsoo Lee 《Optical Review》2014,21(5):694-697
In this study, we fabricated a fiber-optic goniometer using a plastic optical fiber, a light-emitting diode, and a photodiode. The cladding of the plastic optical fiber was removed at 0.5–3mm intervals regularly to increase the bending loss of the plastic optical fiber. Also, the output voltages of the photodiode based on light intensity that measured using the fiber-optic goniometer were measured light intensities using the fiber-optic goniometer were measured to evaluate the linearity of the fiber-optic goniometer. Finally, we measured the responses of the fiber-optic goniometer for gait speeds of 3, 5, and 10 km/h using a data acquisition board and a LabVIEW program. 相似文献
977.
In this paper, we investigate the influence of boundary dissipation on the decay property of solutions for a transmission problem of Kirchhoff type wave equation with boundary memory condition. By introducing suitable energy and Lyapunov functionals, we establish a general decay estimate for the energy, which depends on the behavior of relaxation function. 相似文献
978.
Reaction of lithio anion derived from diethyl alkanephosphonate in the presence of 2 eq. of n-BuLi with benzenesulfonyl chloride gives directly the corresponding diethyl-1-chloro-1-lithioalkanephosphonate, which reacts in situ with carbonyl compounds followed by intramolecular substitution reaction to give 1,2-epoxyalkanephosphonates. 相似文献
979.
Seung Yeop Lee Min Hoon Baik Hye-Ryun Cho Euo Chang Jung Jong Tae Jeong Jong Won Choi Young Boo Lee Yong Jae Lee 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(3):1311-1319
Sulfate-reducing bacteria and their by-products, such as iron sulfides, are widely distributed in groundwater and sediments, and can affect subsurface aqueous chemistry. Here we show the catalytic reduction of hexavalent uranium by FeS particles, which were largely generated by the activities of Desulfovibrio desulfuricans and D. vulgaris in anaerobic condition. Characterization of FeS particles by X-ray diffraction and high-resolution transmission electron microscopy revealed the presence of mackinawite having thin and flexible platy sheets with 0.5-nm lamellar spacing. This biogenic phase mediated abiotic reduction of U(VI) to U(IV) which was confirmed by UV–Vis absorption spectroscopy. The U conversion occurred through surface catalysis that involved adsorption of aqueous U(VI)–carbonate complexes (predominantly UO2(CO3) 3 4? ) onto the mackinawite, but the transformed uranium was then released and remained in suspended form in the solution phase. This surface catalysis and subsequent U(IV) remobilization has not been reported as a pathway to occur under sulfate-reducing conditions. Our results suggest that the iron sulfide solid, which is characteristic of conductive property, is very sensitive and variable depending on the electron supplying and transferring environment, negatively affecting the surface uranium to be strongly stabilized and fixed on the FeS surface. 相似文献
980.
Younjin Park Won Sik Shin Sang-June Choi 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):789-799
Fishbone as a main backfill material of permeable reactive barrier to remediate groundwater contaminated with Co and Sr was investigated through single- and bi-solute competitive sorptions. The single-solute sorption data were fitted by Freundlich, Langmuir and Dubinin-Radushkevich models. The coefficients of determination (R 2 > 0.91) indicated that all models fitted well. Maximum sorption capacities (q mL ) of Co and Sr predicted by the Langmuir model were 0.55 mmol/g and 0.50 mmol/g, respectively. The bi-solute competitive sorption of the metals was analyzed by the Langmuir, competitive Langmuir, Sheindorf-Rebhun-Sheintuch (SRS) and P-factor models. The sorbed amount of one solute in bi-solute system decreased due to competition with the other solute. Langmuir model parameters for single- (q mL and b L ) and bi-solute (q mL * and b L * ) competitive sorptions were compared to analyze the effect of competition between the metals. The competitive Langmuir, SRS and P-factor models predicted the bi-solute competitive sorption data well (R 2 > 0.93). 相似文献