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91.
92.
Ke Jian Liu Jin Jie Jiang Li Li Ji Xianglin Shi Harold M. Swartz 《Research on Chemical Intermediates》1996,22(5):499-509
Application of the spin trapping technique in intact animals requires an understanding of the stability and distribution of the spin traps and their spin adducts in vivo. We studied the stability of DMPO in vivo in mice using HPLC and the stability of spin adducts of DMPO by EPR in plasma, whole blood, peritoneal fluid, and homogenized heart tissue of the rat. At 15 minutes after intraperitoneal injection DMPO had similar concentrations in the liver, heart, and blood of the mice and 40% remained in the organs 2 hours after the injection. In contrast, the spin adduct DMPO-OH was short lived, with a half-life of 3.0 minutes in plasma, and was not detectable 1 minute after formation in whole blood and homogenized heart tissue. The carbon centered spin adduct DMPO-CH(OH)CH3 was more stable, having half-lives of 16, 11, 3.6, and 0.79 minutes in plasma, peritoneal fluid, whole blood, and homogenized heart tissue, respectively. The spin adduct DMPO-SO3 was sufficiently stable for the adduct to be observed directly from living mice. 相似文献
93.
合成子Ni替代铁酸稀土复合氧化物LaF31-xNixO3(x=0.1-0.6),对样品进行了XRD、IR及Mossbauer谱测试,结果表明:x=0\1,0\2,0\3的样品为正交相,x=0.5,0.6的样品为菱方相;伴随相结构从正交向菱方结构的转变,IR谱上Fe(Ni)-O键伸振动谱带向高频移动近20cm^-1,Mossbauer谱测试表明Fe均处于+3自旋态,Ni离子以+3价进入晶格。 相似文献
94.
1INTRODUCTIONRecentlyorganicnonlinearoptical(NLO)materialsarebeingdevelopedforfre-quencyconversionoflaserinopto-electrics-Especiallybluelightisrequiredforopti-calmemoryofhighdensityrecording.Becauseadiodelaserisusedasalightsource,thenonlinearmaterialswhichhaveextremelyhighvalueofNLOcoefficientsandthetransmissionofblueregionarenecessary.Sincethesecond-orderNLOpropertyoforganiccompoundisderivedfromconjugateddelocalizedrrelectrons,thecompoundswhichhavebeenreportedhavefocusedonthenitroanil… 相似文献
95.
96.
97.
Jiři Votinský Jaroslava Kalousová Ludvík Beneš 《Journal of inclusion phenomena and macrocyclic chemistry》1992,14(1):19-24
The paper deals with the relations between host lattices and guest molecules. Several types of interaction of the guest molecules and the host material are explained and some conclusions are made about the arrangement of various guest molecules in the van der Waals' gap. 相似文献
98.
Jian Ping LI* Ping LIU Yu Lu WANG College of Chemistry & Environmental Science Henan Normal University Xinxiang Key Laboratory of Environmental Science Technology of High Education of Henan Province Xinxiang 《中国化学快报》2003,14(7)
Azo compounds are widely utilized as analytic reagents and dyes1, they can also be used in material of non-linear optics, material of optics information storing in laser disks, and dyes with oil solubility in photochromy in modern technology2. Recently, many noteworthy studies have shown that some azo compounds possess excellent optical memory and photoelectric properties3,4. For example, polymer scaffolds bearing azobenzene-potential are useful for optical information storage, azo-dye doped… 相似文献
99.
100.
Molecular Recognition of Bridged Bis(β-cyclodextrin)s Linked by Phenylenediseleno Tether on the Primary or Secondary Side with Fluorescent Dyes 总被引:1,自引:0,他引:1
A Novel β-cyclodextrin dimer,2,2′-o-phenylenediseleno-bridgedbis(β-cyclodextrin)(2),has been synthesized by reaction ofmono-[2-O-(p-tolylsulfonyl)]-β-cyclodextrin and poly(o-phenylenediselenide).The complexation stability constants(K_s)and Gibbs free energy changes(-ΔG°)of dimer 2 with fourfluorescence dyes,that is,ammonium 8-anilino-1-naphthalene-sulfonate(ANS),sodium 6-(p-toluidino)-2-naphthalenesul-fonate(TNS),Acridine Red(AR)and Rhodamine B(RhB)have been determined in aqueous phosphate buffer solution(pH=7.2,0.1 mol·L~(-1)at 25℃ by means of fluorescence spec- 相似文献