ICP-AES法测定色漆可溶性金属含量

用ICP-AES法测定了色漆中的“可溶性”金属铬、镉、铅元素，考察了不同酸度对分析结果的影响，优化了测试条件。进行了回收率和精密度试验。并用原子吸收光谱国标方法进行对照，结果一致。     

Fluorinated amino acids in protein design and engineering

Selective incorporation of unnatural amino acids into proteins is a powerful tool for illuminating the principles of protein design. In particular, fluorinated amino acids have recently emerged as valuable building blocks for designing hyperstable protein folds, as well as directing highly specific protein-protein interactions. We review the collagen mimetic and coiled coil peptide systems that exemplify generalizable paradigms for future design. The unique electronic and phase properties of fluorocarbons are discussed, and protein synthesis using unnatural amino acids is briefly reviewed.     

Trimethylsilyl and halodimethylsilylmethyl derivatives of some diamines

The reaction of chloro-and bromomethyldimethylchlorosilane with a variety of N,N,N'-trialkyldiamines resulted in solids which, on the basis of proton, ²⁹Si, and ³⁷Cl chemical shift and molecular weight data, are assumed to have a dimeric or trimeric structure (in solution) that contains a 4-coordinate silicon:

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Models for the lower S states of photosystem II: a trinuclear mixed-valent MnII/MnIV/MnII complex

The trinuclear complex Mn(3)(pko)(4)(CH(3)O)(2)(SCN)(2).CH(3)OH, 1, where Hpko is 2,2'-dipyridylketonoxime, is a rare example of a complex simultaneously containing Mn(II) and Mn(IV). X-ray crystallography and XANES spectroscopy clearly distinguish the Mn(II)(2)Mn(IV) valence isomer from the more commonly observed Mn(III)(2)Mn(II) formulation. Fits to variable-temperature magnetic susceptibility data indicate that the Mn(II) and Mn(IV) are ferromagnetically coupled (J = +6.13 cm(-1)) and that 1 has an S = (13)/(2) ground state.