STUDY OF BIMETALLIC COMPLEXES OF RARE-EARTH LITHIUM - SYNTHESIS AND CRYSTAL-STRUCTURE OF THE (LACL)DME(MU-2-CL)5(MU-3-CL) (LA.DME)LI(THF)2

The reaction between LaCl_3 and LiCl in THF at room temperature, with hexane as precipitant and glycol dimethyl ether as complexing agent, has been studied. A complex with the composition of (LaCl)DME(μ_2-Cl)_5(μ_3-Cl)(La·DME)Li(THF)_2 has been synthesized, its structure was studied by single crystal X-ray diffraction technique. The diffraction intensities were collected at about —100℃. The complex belongs to the triclinic space group P1 with α=11.123(3), 6=16.564(5), c=8.653(3)A, α=95.16(3), β=...

SYNTHESIS AND CRYSTAL-STRUCTURES OF THE BIMETALLIC RARE-EARTH COMPLEXES AND STUDIES ON INSERTION MECHANISM OF DIENES POLYMERIZATION

The deepening of the studies on essentials of rare earth coordination catalyst brings about more and more reports on model compounds as active centre of the catalyst. Among them the most significant researches are those with identification of the crystal structures of compounds.

IR AND RAMAN-SPECTRA STUDIES OF THE RARE EARCH COMPLEXES WITH GLUTATHIONE

The complexes of rare earth ions with glutathione were prepared and charactrized by IR and Raman spectroscopy in the solid state. Based on the spectral results, the structure and coordination sites of the ligand in these complexes were determined.

SYNTHESIS AND VIBRATIONAL SPECTRUM STUDIES OF RARE EARTH COMPLEXES WITH CYCLOHEXANE CARBOXYLIC ACID

The solid state complexes of trivalent lanthanid, yttrium and scandium with cyclohexane carboxylic acid have been isolated and characterized by IR and Raman spectroscopy. It was found that there are only chelated carboxylate groups in the scandium complex and that there are the chelated, bridged and chelate-bridged carboxylate groups in other rare earth complexes. The former is a mononuclear complex and the latter is a polynuclear polymer. The RE—O coordinate bonds possess the characters of convalent ionic ...

Structural analysis of peptides of PSII light-harvesting complexes in siphonous green algae, Codium fragile

peptide composition and arrangement of 4 major light-harvesting complexes LHCP1-3 and LHCP3, isolated from siphonous green algae (Codium fragile (Sur.) Hariot.) were investigated. LHCP1 showed five main peptides, 34.4, 31.5, 29.5, 28.2 and 26.5 kD in SDS-PAGE, the 34.4 and 31.5 kD peptides were never found in higher plants. LHCP3 contained the other four kinds of LHCP1 peptides except 34.4 kD, while LHCP3, consisted of only 28.2 and 26.5 kD peptides. We found that 34.4, 28.2 and 26.5 kD peptides were easy to decompose from LHCP1 when subjected to SDS-PACE without pretreatment. They might be located at the exterior of LHCP1, while the 31.5 and 29.5 kD peptides were at the central part. The 28.2 and 26.5 kD peptides often occurred in CPa, the center complex of PS II. They are possibly the LHC II peptides tightly associated with CC II. According to the results described above, a peptide map of LHCP1 was sketched.

Characteristics and comparative study of chlorophyll-protein complexes from siphonous green algae

By mild PAGE method, 11, 11, 7 and 9 chlorophyll-protein complexes were isolated from two species of siphonous green algae ( Codium fragile (Sur.) Harlot and Bryopsis corticulans Setch.), green alga (Ulothrix flacca (Dillw.) Thur.), and spinach (Spinacia oleracea Mill.), respectively. Apparent molecular weights, Chi a/b ratios, distribution of chlorophyll, absorption spectra, low temperature fluorescence spectra of these complexes were determined, and compared with one another. PS I complexes of two siphonous green algae are larger in apparent molecular weight because of the attachment of relative highly aggregated LHC I. Four isolated light-harvesting complexes of PSII are all siphonaxanthin-Chl a/b-protein complexes, and they are not monomers and oligomers like those in higher plants. Especially, the absence of 730 nn fluorescence in PS I complexes indicates a distinct structure and energy transfer pattern.

Diversity of pigment-protein complexes of photosynthetic organisms.

PS I, PS II and light-harvesting complexes (LHC) in oxygen evolving photosynthetic organisms were reviewed. These organisms include cyanobacteria, red algae, brown algae, diatoms, chrysophytes, dinophytes, xanthophytes, crypophytes, green algae and green plants. The diversity of pigment-protein complexes that fuel the conversion of radiant energy to chemical bond energy was highlighted, and the evolutionary relationships among the LHC structural polypeptides and the characteristics of the fluorescence emission of PS I at 77 K was discussed.

Isolation and nomenclature of pigment-protein complexes from the brown alga (Undaria pinnatifida Harv.)

Eight kinds of pigment-protein complexes were resolved from the thylakoid membrane of the brown alga (Undaria pinnatifida Harv.) by using non-ionic detergent decanoyl-N-methylglucamide and PAGE technique. According to the apparent molecular weights, spectra characteristics, polypeptide compositions and referring to the higher plant spinach, eight pigment-protein complexes were named under Anderson's terminology system as CP I a, CP I, CPa, LHC1, LHC2, LHC3, LHC4, LHC5.

Epoxidation of styrene with NaOCl and catalyzed by nickel(II) complexes

Epoxidation of styrene was catalyzed by some nickel(II) complexes, with NaOCl as the oxygen donor. The catalyst Ni(PA)(2). 2H(2)O has been found to be stable for the epoxidation of styrene. Some additives were introduced in the reaction to improve the "micro-environment" of the catalyst. Radical trap had little influence on styrene epoxidation. It was interesting to find that phase-transfer agent had negative influence on epoxidation in this biphase reaction. A possible mechanism of styrene epoxidation catalyzed by Ni(PA)(2). 2H(2)O has been proposed.