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排序方式: 共有545条查询结果,搜索用时 14 毫秒
1.
Asadollah Zarif Farhad Amarloo Faeze Pourazimi Najmeh Kaftani Zahra Rostamabadi Ebrahim 《Journal of fluorescence》2022,32(5):1639-1650
Journal of Fluorescence - Malachite green (MG) is a dye that has been presented to use as photosensitizers for photodynamic therapy (PDT). Nonlinear absorption coefficient (β) and nonlinear... 相似文献
2.
The luminous intensity unit of candela was realized based on filter-radiometer, which is traceable to detector-based primary standard electrical substitution cryogenic radiometer (ESCR). In that realization the traditional Osram Wi41/G-type incandescent lamp and filter-radiometer consisting of an aperture, a V(λ) filter and a silicon photodiode based trap detector were used as light source and detection element, respectively. Measurement techniques of effective aperture area, spectral transmittance of V(λ) filter and absolute responsivity of trap detector are also presented. 相似文献
3.
Donald R. Schreiber James Huebner Seyed Rahmani Frank J. Millero 《Journal of solution chemistry》1993,22(3):201-210
Enthalpies of mixing (m
H) aqueous solutions of CoCl2, CuCl2, and MnCl2 with NaCl solutions were measured at constant ionic strengths of 0.5, 1.0, and 3.0 molal at 25°C. The excess enthalpy equations of Pitzer were then fit to the resulting m
H data. The resulting parameters are the temperature derivatives of the activity coefficient mixing parameters in the Pitzer system. The heat of mixing data for CoCl2 and CuCl2 were in agreement with earlier isomolal results by other workers. 相似文献
4.
ALI Rahmani Christian B. Eckardt Richard G. Brereton James R. Maxwell 《Photochemistry and photobiology》1993,57(S1):1048-1052
Abstract— This paper reports a new method for monitoring the allomerization reactions of chlorophyll a and pheo-phytin a. Complex mixtures are generated from illuminating pure compounds and monitored using both diode array high-performance liquid chromatography (DAD-HPLC) and liquid chromatography-mass spectrometry (LC-MS). LC-MS allows molecular weight and fragment ion analysis of significant HPLC peaks. Five products of the degradation of chlorophyll a can be simultaneously detected in a mixture, namely the monohydroxy allomer, the methoxylactone allomer, pheophytin a and the two corresponding allomers of the pheophytin. It is demonstrated that more than one pathway must be involved in the in vitro photodegradation of chlorophyll a as shown by the simultaneous existence of several intermediates. 相似文献
5.
Aluminium dodecyl sulfate trihydrate [Al(DS)3].3H2O is easily prepared and can be used as a Lewis acid surfactant catalyst in water to conduct the highly efficient Michael addition of indoles and pyrrole to alpha,beta-unsaturated electron-deficient compounds at room temperature. 相似文献
6.
Summary In the present study the effects of addition of iron on the catalytic activity and Si tolerability of Pt/g-Al2O3in the total oxidation of volatile organic compounds were investigated. Preliminary results showed that there is a noticeable
improvement effect on Si-tolerance of catalyst, particularly for short term poison exposure. Bulk analysis of deposited silicon
on the catalyst surface indicated that both Pt/g-Al2O3and iron-doped pellets had roughly the same silicone uptakes. Deactivation of catalyst was reversible and much faster for
iron doped sample. The promoting effects of iron were related to its electronegativity and, to blocking of fewer Pt sites
when iron is present at the surface of the catalyst. 相似文献
7.
[11C]Carbon monoxide at low concentrations, aryl halides and amines were used in the palladium-mediated synthesis of twenty 11C-amides. In the study several approaches to improve the radiochemical yield were explored. Eight of the selected amides were prepared by in situ activation of the amines using lithium bis(trimethylsilyl)amide and the radiochemical yields of these reactions were improved compared to utilising a previous reported method. In the synthesis of 1-[carbonyl-11C]benzoyl-3-methyl-1H-indole (11) from 3-methyl-1H-indole (25), the corresponding organotin-amine was prepared prior to the acylation reaction. In a typical experiment, N-(4-hydroxyphenyl)[carbonyl-11C]acetamide (5) was prepared in 15% radiochemical yield using 4-aminophenol (20) but the yield increased to 63% when the amine was activated by lithium bis(trimethylsilyl)amide. 相似文献
8.
Richard G. Brereton Ali Rahmani Yi-zeng Liang Olav M. Kvalheim 《Photochemistry and photobiology》1994,59(1):99-110
Abstract –The products of chlorophyll allomerization in methanol were isolated and analyzed by open column sucrose chromatography, liquid chromatography mass spectrometry (LCMS) and DAD-HPLC (diode-array high-performance liquid chromatography). Four main bands were found with molecular ions of (a) 908, (b) 938, (c) 938 and (d) 938, consistent with the structures (a) 132 -hydroxy-chlorophyll a (II), (b) and (c) Mg(II)-31 ,32 -didehydro-151 -hydroxy-151 -methoxy-rhodochlorin-15 acetic acid δ-lactone 152 -methyl 173 -phytyl ester and its epimer (III) and (d) Mg(II)-31 ,32 -didehydro-rhodochlorin-15-glyoxylic acid 131 ,152 -dimethyl 173 -phytyl ester (IV), evidence enhanced by UV/visible spectroscopy, chromatographic coelutions and chemometrics. Chlorophyll a was degraded both in the dark and light, under O2 and N2 . DAD-HPLC of the resultant degradation mixtures were analyzed using the chemometric heuristic-evolving latent projection method for resolution. Ultraviolet/visible spectra of II and III are reproducibly extracted from the mixtures after a short degradation time, whereas III and IV are the dominant compounds after longer degradation times. Changes in relative elution order of IV using open column chromatography and reverse-phase HPLC are established. A possible allomerization pathway is proposed. 相似文献
9.
10.
Farhad Sattari Soghra Mirershadi 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(10):227
In this paper the transmission and the shot noise properties through the strain-inducedgraphene superlattices are studied. It is found that for the zigzag direction strain theFano factor shows a peak at new Dirac-like point and the position of the new Dirac pointvaries against the strain. Also, Fano factor has an oscillatory behavior with respect tostrain strength and the oscillation period decreases by increasing the number of barriers.However, for the armchair direction strain the transmission can be blocked by the electricbarrier and the Fano factor approaches 1, this is different from the zigzag directionstrain. 相似文献