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951.
Chlorobis(2,2,2-trichloroethoxy)- and dichloro(2,2,2-trichloroethoxy)iron(III) have been synthesized. They react with various oxygen and nitrogen donor ligands to yield adducts formulated as FeCl(OCH2CCl3)2 · 2 L or FeCl2(OCH2CCl3) · 2 L (L = ligand). The depressed magnetic moments of these compounds show the presence of strong antiferromagnetic interactions between iron atoms. The infrared and 1H nmr spectra establish the presence of bridging and terminal alkoxy groups and ligands (L) are cis to each other. The electronic spectra of these complexes indicate that each iron atom is approximately octahedrally coordinated. Mass spectral data are in favour of dimeric structure for the title compounds. 相似文献
952.
Riboflavin and UV-Light Based Pathogen Reduction: Extent and Consequence of DNA Damage at the Molecular Level 总被引:3,自引:0,他引:3
Vijay Kumar Owen Lockerble Shawn D. Kell Patrick H. Ruane Matthew S. Platz Christopher B. Martin Jean-Luc Ravanat Jean Cadet Raymond P. Goodrich 《Photochemistry and photobiology》2004,80(1):15-21
We are developing a technology based on the combined application of riboflavin (RB) and light for inactivating pathogens in blood products while retaining the biological functions of the treated cells and proteins. Virus and bacteria reduction measured by tissue culture infectivity or colony formation with UV light alone and in combination with RB yield equivalent results. The effects of RB as a sensitizing agent on DNA in white cells, bacteria and viruses in combination with UV light exposure have been evaluated. UV-mediated DNA degradation in Jurkat T cells and leukocytes in plasma as measured by the FlowTACS assay was significantly increased in the presence of RB. Agarose gel electrophoretic analysis of DNA in Escherichia coli and leukocytes in plasma demonstrated enhanced DNA degradation in the presence of RB. UV light in combination with RB prevented the reactivation of lambda phage compared with samples irradiated in the absence of RB. UV-mediated oxidative damage in calf thymus DNA was also enhanced in the presence of RB. These observations clearly demonstrate that the presence of RB and UV light selectively enhances damage to the guanine bases in DNA. These data also suggest that the type and extent of damage to DNA for virus in the presence of RB and light make it less likely to be repaired by normal repair pathways available in host cells. 相似文献
953.
The Rh(II)-catalyzed reaction of dimethyl diazomalonate with aryl aldehydes and beta-nitrostyrenes results in the formation of highly substituted tetrahydrofurans. The reaction may be considered to involve the Huisgen dipolar cycloaddition of the carbonyl ylide, generated from the dicarbomethoxycarbene and the aldehyde, to the beta-nitrostyrene. The diastereoselectivity of the reaction may be attributed to the concerted nature of the carbonyl ylide cycloaddition. 相似文献
954.
A microfluidic lab-on-a-chip (LoC) platform for in vitro measurement of glucose for clinical diagnostic applications is presented in this paper. The LoC uses a discrete droplet format in contrast to conventional continuous flow microfluidic systems. The droplets act as solution-phase reaction chambers and are manipulated using the electrowetting effect. Glucose is measured using a colorimetric enzyme-kinetic method based on Trinder’s reaction. The color change is detected using an absorbance measurement system consisting of a light emitting diode and a photodiode. The linear range of the assay is 9-100 mg/dl using a sample dilution factor of 2 and 15-300 mg/dl using a sample dilution factor of 3. The results obtained on the electrowetting system compare favorably with conventional measurements done on a spectrophotometer, indicating that there is no change in enzyme activity under electrowetting conditions. 相似文献
955.
Fan X Potluri VK McLeod MC Wang Y Liu J Enick RM Hamilton AD Roberts CB Johnson JK Beckman EJ 《Journal of the American Chemical Society》2005,127(33):11754-11762
Several oxygenated hydrocarbons, including acetylated sugars, poly(propylene glycol), and oligo(vinyl acetate), have been used to generate CO2-soluble ionic surfactants. Surfactants with vinyl acetate tails yielded the most promising results, exhibiting levels of CO2 solubility comparable to those associated with fluorinated ionic surfactants. For example, a sodium sulfate with single, oligomeric vinyl acetate (VAc) tails consisting of 10 VAc repeat units was 7 wt % soluble in CO2 at 25 degrees C and 48 MPa. Upon introduction of water to these systems, only surfactants with the oligomeric vinyl acetate tails exhibited spectroscopic evidence of a polar environment that was capable of solubilizing the methyl orange into the CO2-rich phase. For example, a single-phase solution of CO2, 0.15 wt % sodium bis(vinyl acetate)8 sulfosuccinate, and water, at water loading (W) values ranging from 10 to 40 at 25 degrees C and 34.5 MPa, exhibited a methyl orange peak at 423 nm. This result indicated that the core of a reverse micelle provided a microenvironment with a polarity similar to that of methanol. Quantum chemical calculations indicate that the acetylated sugars may be too hydrophilic to readily form reverse micelles, whereas the VAc-based surfactants appear to have the correct balance of hydrophilic and hydrophobic forces necessary to form reverse micelles. 相似文献
956.
Sunehri L. Chadha Vijay Sharma Sat P. Taneja Deo Raj 《Transition Metal Chemistry》1986,11(10):369-371
Summary The preparation, magnetic moments, i.r., reflectance and57Fe Mössbauer spectra of adducts of tris(2,2,2-trichloroethoxy)iron (III) complexes are reported. An alkoxybridged structure is supported by i.r. spectra.57Fe Mössbauer spectra are explained in terms of two inequivalent sites in highspin iron(III) octahedral symmetry.Abbreviations Pic-O
-picolineN-oxide
- Ur
urea
- DMU
N,N-dimethylurea
- Suc
succinimide
- Diox
dioxan
- Bipy
2,2-bipyridine
- Phen
1,10-phenanthroline 相似文献
957.
Dharam V.S. Jain Vijay K. Singla Suraj B. Saini Rajwant S. Sidhu 《The Journal of chemical thermodynamics》1983,15(12):1105-1107
Excess molar volumes VmE as function of mole fraction x for methylcyclohexane + benzene, + methylbenzene, + 1,4-dioxane, and + tetrahydrofuran are reported at 303.15 K. The excess molar volumes are positive and indicate the presence of weak interactions. 相似文献
958.
959.
We study the set of subgame perfect equilibria associated with then-person noncooperative bargaining mechanism proposed by Hart and Mas-Colell (1992). Our results pertain to transferable utility games. The set of perfect equilibria depends on the parameter representing the continuation probability, . For general TU games, we characterize the set of payoffs from perfect equilibria for (a) small values of and (b) large values of . For symmetric games a complete characterization for all values of is provided.We are grateful to Andreu Mas-Colell for help and encouragement and to two referees for every helpful comments. 相似文献
960.
A variety of five-membered ring oxazoles have been synthesised with complete regiocontrol and without the requirement for ring oxidation via a reaction sequence based on a vinyl sulfonamide template. 相似文献