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971.
Ki Won Lim Jin Yong Jun Byeong Jun Lee 《Journal of Thermal Analysis and Calorimetry》2012,109(1):487-494
The calorific value is defined as the amount of heat which would be released by the complete combustion in air, in such a way that the pressure remains constant, all the combustion products except water are gaseous states and all the products returned to the temperature of the reactants. Recently, the mixed fuel like LPG, LNG, hythane, etc., become more popular. But the composition of these fuels changes with time and place where it was produced, which give direct impacts on the calorific value and performance of the heating apparatus. Therefore, the accurate measurements of the calorific value become an issue in the refinery industries and the national standardization fields. So, flame calorimeter was manufactured and characterized to measure calorific value of the gaseous fuel in the flow situations. Electric substitution method initiated by Alexandrov was adopted. Peltier elements were used to emit the heat supplied by a heater and a flame to the cooling water. Freon-11 was used as a heat carrier. To get the accurate calorific value by the experiments conducting in the normal laboratory conditions, correction methods were proposed to count variations in the experimental conditions such as temperatures, electric powers, etc. It was found out that the corrected calorific value of pure methane had 0.36% relative deviation to the standard value. 相似文献
972.
Xiao L Ha JW Wei L Wang G Fang N 《Angewandte Chemie (International ed. in English)》2012,51(31):7734-7738
Keeping track: By combining differential interference contrast (DIC) image pattern recognition with DIC polarization anisotropy, the exact full three-dimensional angular information of individual tilted gold nanorods positioned in the focal plane of the objective lens can be readily determined. The angular rotational modes and kinetics of individual in-focus gold nanorods can thus be resolved dynamically. 相似文献
973.
Wee KR Han WS Cho DW Kwon S Pac C Kang SO 《Angewandte Chemie (International ed. in English)》2012,51(11):2677-2680
A bright combination: a new type of donor-acceptor dyad, carbazolylaryl-substituted ortho-carboranes, which are conveniently prepared from the corresponding acetylenes and decaborane pathways, showed unique excited-state behavior associated with electron transfer unlike the meta- and para-counterparts. 相似文献
974.
Vanecht E Binnemans K Patskovsky S Meunier M Seo JW Stappers L Fransaer J 《Physical chemistry chemical physics : PCCP》2012,14(16):5662-5671
The stability of gold nanoparticles synthesised by sputter deposition has been studied in situ in 1-butyl-3-methylimidazolium ionic liquids with bis(trifluoromethylsulfonyl)imide, tetrafluoroborate, hexafluorophosphate and dicyanamide anions with UV-VIS absorption spectroscopy and transmission electron microscopy. Besides the growth of the gold nanoparticles, two other processes were observed after sputtering, namely aggregation and sedimentation of these nanoparticles. To model the absorption spectra of the sputtered gold nanoparticles, generalized multiparticle Mie calculations were performed. These theoretical calculations confirm the increase in absorbance at longer wavelength for larger aggregates and are in agreement with the experimental observations. It was found that the kinetics of aggregation and sedimentation scale with the viscosity of the ionic liquid. Small amounts of water were found to have a large detrimental influence on the stability of the colloidal suspensions of the gold nanoparticles in ionic liquids. From the large discrepancy between the theoretical and the experimentally observed stability of the NPs, it was concluded that structural forces stabilize the gold nanoparticles. This was also borne out by AFM measurements. 相似文献
975.
Kim BH Hong WG Yu HY Han YK Lee SM Chang SJ Moon HR Jun Y Kim HJ 《Physical chemistry chemical physics : PCCP》2012,14(4):1480-1484
We have obtained high pressure H(2) isotherms with respect to the interlayer distance of multilayered graphene oxide (GO) modulated by thermal annealing. The maximum storage capacity is 4.8 (0.5) wt% at 77 K (298 K) and at 9.0 MPa pressure. We found the optimum GO interlayer distance for maximum H(2) uptake at 6.5 ?, similar to the predicted distances from first-principles calculations for graphite materials. Our results reveal that multilayered GO can be a practical material of choice to allow the use of graphene as a hydrogen storage material, provided that only small amounts of O and OH functional groups exist as spacers on GO sheets. 相似文献
976.
Jae Myung Park Hyung Won Ryu Hoe Kyoung Lee Deuk Ho Lee 《Czechoslovak Mathematical Journal》2012,62(4):869-878
In this paper, we define the ${M_\alpha }$ -integral of real-valued functions defined on an interval [a, b] and investigate important properties of the ${M_\alpha }$ -integral. In particular, we show that a function f: [a, b] → R is ${M_\alpha }$ -integrable on [a, b] if and only if there exists an $AC{G_\alpha }$ function F such that F′ = f almost everywhere on [a, b]. It can be seen easily that every McShane integrable function on [a, b] is ${M_\alpha }$ -integrable and every ${M_\alpha }$ -integrable function on [a, b] is Henstock integrable. In addition, we show that the ${M_\alpha }$ -integral is equivalent to the C-integral. 相似文献
977.
Self-organized long-range order structures, such as stripe domains and magnetic skyrmion lattices, are formed by the competition between ferromagnetic exchange interaction and Dzyaloshinskii–Moriya (DM) interaction. We investigated the properties of the magnetic structures generated by a DM interaction under the influence of anisotropy or magnetic dipole interaction, by performing Monte-Carlo simulated annealing. We constructed phase maps in external-field and anisotropy space to study the effect of anisotropy or dipole interaction on the phase boundaries between the magnetic structures. The simulation results show that the phase boundaries are sensitive to perpendicular anisotropy and that the skyrmion lattice region in phase space is extended under easy-plane anisotropy. The effect of the long-range dipole interaction was studied and was found to stabilize the skyrmion lattice phase and reduce the size of the magnetic structures. 相似文献
978.
Shiv P. Patel J.C. Pivin M.K Patel Jonghan Won Ramesh Chandra D. Kanjilal Lokendra Kumar 《Journal of magnetism and magnetic materials》2012
The effect of swift heavy ions (SHI) on magnetic ordering in ZnS thin films with Co ions substituted on Zn sites is investigated. The materials have been synthesized by pulsed laser deposition on substrates held at 600 °C for obtaining films with wurtzite crystal structure and it showed ferromagnetic ordering up to room temperature with a paramagnetic component. 120 MeV Ag ions have been used at different fluences of 1×1011 ions/cm2 and 1×1012 ions/cm2 for SHI induced modifications. The long range correlation between paramagnetic spins on Co ions was destroyed by irradiation and the material became purely paramagnetic. The effect is ascribed to the formation of cylindrical ion tracks due to the thermal spikes resulting from electron–phonon coupling. 相似文献
979.
Nam TS Choi SH Rah SY Kim SY Jang W Im MJ Kwon HJ Kim UH 《Experimental & molecular medicine》2006,38(6):718-726
ADP-ribosyl cyclase (ADPR-cyclase) produces a Ca2+-mobilizing second messenger, cyclic ADP- ribose (cADPR), from beta-NAD+. A prototype of mammalian ADPR-cyclases is a lymphocyte antigen CD38. Accumulating evidence indicates that ADPR-cyclases other than CD38 are expressed in various cells and organs. In this study, we discovered a small molecule inhibitor of kidney ADPR-cyclase. This compound inhibited kidney ADPR-cyclase activity but not CD38, spleen, heart or brain ADPR-cyclase activity in vitro. Characterization of the compound in a cell-based system revealed that an extracellular calcium-sensing receptor (CaSR)- mediated cADPR production and a later long-lasting increase in intracellular Ca2+ concentration ([Ca2+]i) in mouse mesangial cells were inhibited by the pre-treatment with this compound. In contrast, the compound did not block CD3/TCR-induced cADPR production and the increase of [Ca2+]i in Jurkat T cells, which express CD38 exclusively. The long-lasting Ca2+ signal generated by both receptors was inhibited by pre-treatment with an antagonistic cADPR derivative, 8-Br-cADPR, indicating that the Ca2+ signal is mediated by the ADPR-cyclase metabolite, cADPR. Moreover, among structurally similar compounds tested, the compound inhibited most potently the cADPR production and Ca2+ signal induced by CaSR. These findings provide evidence for existence of a distinct ADPR-cyclase in the kidney and basis for the development of tissue specific inhibitors. 相似文献
980.
Gastric cancer is one of the most common cancers worldwide. The purpose of this study was to find out potential markers for gastric cancer. Tumor and normal tissues from 152 gastric cancer cases were analyzed by two-dimensional gel electrophoresis (2-DE). The images of silver stained gels were analyzed and statistical analysis of spot intensities revealed that spot 4262 showed higher expression (5.7-fold increase) in cancer tissues than in normal tissues (P < 0.001). It was identified by peptide mass fingerprinting as nicotinamide N-methyltransferase (NNMT). A monoclonal antibody with a detection limit down to 10 ng was produced against NNMT in mouse. Using the prepared monoclonal antibody, western blot analysis of NNMT was performed for gastric tissues from 15 gastric cancer patients and two gastric ulcer patients. The results corroborated those of 2-DE experiments. A single spot was detected in gastric ulcer tissues while four to five spots were detected in gastric cancer tissues. In cancer tissues, two additional spots of acidic and basic form were mainly detected on 2-DE gels. This suggests that NNMT receives a post-translational modification in cancer- specific manner. 相似文献