聚醚醚酮酮和含联苯聚醚醚酮酮共聚物的熔融热

根据Ｆｌｏｒｙ热力学统计理论和比容－熔融热作国法，由ＤＳＣ结果得到了不同联苯含量的聚醚醚酮酮－含联苯聚醚醚酮酮（ＰＥＥＫＫ－ＰＥＢＥＫＫ）共聚物的熔融热，两种方法获得的结果吻合。在此基础上给出了ＰＥＥＫＫ－ＰＥＢＥＫＫ共聚物不同联苯含量的熔点计算表达式。结果还表明，随着联苯含量ｎＢ，的变化，明显改变；当ｎＢ＝０．３５时，ＰＥＥＫＫＰＥＢＥＫＫ共聚物的值最小。     

Synthèse d'hétérocycles en catalyse par transfert de phase

A general study of the chemical behavior of heterocyclic anions, dianions and dianionic reagents under phase transfer catalysis conditions allowed us to synthesize various heterocyclic compounds such as imidazo[2,1-b]thiazole and derivatives; imidazo[2,1-b]thiazine and imidazo[2,1-b]benzothiazepine. Reaction conditions e.g., catalyst, solvent, temperature, etc., are indicated.     

Separation of alkylaminonaphthylenesulfonyl peptides and amin acids by high-performance liquid chromatography. Methods for measuring melanotropin inhibiting factor breakdown

N,N-Dimethyl diethyl, dipropyl, dibutyl, and N-monoisopropylaminoaphthylenesulfonyl derivatives of melanotropin inhibiting factor (MIF) and its metabolites were prepared, and their chromatographic behavior was investigated with thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), using five solvent systems on polyamide layers and ten solvent systems on muBondapak C18 and muBondapak phenyl columns. A mixture of MIF and its metabolites derivatized with Dns chloride was adequately resolved by two-dimensional chromatography on polyamide layer with solvent systems, formic acid-water (3:97) and benzene-acetic acid (9:1). Bns-MIF and its metabolites were separated with muBondapak C18 column with the solvent system acetonitrile-0.01 M sodium sulphate buffer, pH 7 (50:50). They were separated into five groups: Gly and Bns acid; Pro-Leu, Leu-Gly and Leu; Pro; Gly-NH2; and MIF. The alkylaminonaphthylenesulfonyl derivates had strong fluorescence, which permitted their detection at the level of 10(-11) to 10(-9) mol. Dns-MIF and its derivatives had the lowest detectable amounts. HPLC with the aid of the Dns derivation is reliable and fast, and is the preferable method for study of neuropeptide breakdown.     

Alkylation d'anions ambidents en catalyse par transfert de phase. Cas des hydroxypyridines

Alkylation of ambident-anions derived from 2- and 4-pyridones yield by phase transfer catalysis, 80% of N-substitution and 20% of O-substitution. Change of salts, solvents, temperature and alkyl halide do not interfere very much with the N- and O-alkylation percentage of substitution. Overall yields range from 40 to 80% with primary or secondary alkyl halides.     

在肽库中进行小肽筛选的初步研究

以合成六肽ＤＧＧＳＡＡ为模型对在噬菌体肽库中进行小肽筛选做了初步研究。结果表明，含有可形成氢键和离子键残基的小肽能够在噬菌体肽库中进行筛选。并用明显提高了筛选的专一性。     

聚氯乙烯复合热稳定剂中铅镉钡的同时测定

聚氯乙烯（PVC）材料广泛应用于建筑、电讯、交通、电子、化工、包装等行业。然而，PVC加工时存在着一个致命的弱点，就是其流动温度为136℃，分解温度为140℃，两者相差仅4℃，给加工带来很大难度，为了能顺利加工就必须加入热稳定剂，热稳定剂是PVC加工不可缺少的主要助剂之一。热稳定剂种类繁多，我国目前大量使用的稳定剂为铅盐及金属皂等稳定剂，产量高达4．5万吨。由于铅、镉、钡等金属元素具有一定的毒性，使用中易造成环境污染，有害于人体健康，因此必须严格加以控制。     

Facile synthesis of C-aryl glycals from sugar-derived lactones

A general entry to C(1) aryl-substituted glycals from the corresponding sugar lactones is described. This approach features one-pot access to aryl glycals. A variety of aryllithium reagents can be used and the method is compatible with various 2-deoxysugar lactones.     

一维链状锰配位聚合物[Mn(4-CPOA)(2,2-bipy)(H_2O)]_n的合成与晶体结构(英文)

0IntroductionThe solid-state chemistry of manganese!car-boxylate coordination polymers has received growingattention over the past few years,owing to their fasci-nating network topologies and potential application inthe field of molecular magnetism and bi…     

土壤微生物ATP、脱氢酶和尿素酶活性的ED50值评价外源镧的生物毒性

０IntroductionRareearthsarenowappliedwidelyinChina，whichcanimprovecropsyieldsandthetheirqualit－ies犤１犦．Thebeneficialeffectsmaybeduetothestimu－latoryeffectsoftheseelementsonthenutrientuptakebyplantsorontheincreasingofchlorophyllsynthesisintheplants犤２犦．Whilealotofresearcheshavebeendoneontheimprovednutritionofcropsafterapplica－tionofrareearths，muchlessattentionhasbeenpaidtothedeteriorationofsoilqualityduetotheapplicationofrareearthsforyears犤３犦．Scientistshavediscoveredthataccumula…     

Theoretical study of the local structure and Raman spectra of CaO-SiO2 binary melts

A procedure for the Raman spectra calculation of vitreous and molten silicates was presented in this paper. It includes molecular dynamics MD simulation for the generation of equilibrium configurations, Wilson's GF matrix method for the calculations of eigenfrequencies and corresponding vectors, electro-optical parameters method (EOPM) for the Raman intensity calculations, and the bond polarizability model (BPM) for the determination of polarizability and polarizability derivative. One of the most important characteristics of this procedure is the achievement of the partial Raman spectra of five tetrahedral units, as well as the total spectral envelope. In this paper, the calculation was carried out for the vitreous and molten calcium silicates with different compositions and at various temperatures. It is worthwhile to note that the calculation is based on statistical configurations distribution in the space and so it is not needed to artificially adjust the full width at half maximum (FWHM) of spectra. It was also tested through the good agreement of the calculated spectra with the experimental, including some regularity of spectral properties. According to the calculation, the symmetrical stretching of whole tetrahedral units, to which the stretching of Si-O(nb) bond gives the main contribution to intensity, is proven to be the dominance in the high-frequency range (800-1200 cm(-1)) and the symmetrical bending of Si-O(b)-Si, to which the stretching of Si-O(b) bond exhibits the main contribution, is the dominance in the medium-frequency range (400-700 cm(-1)). As the first theoretical results, the Raman scattering coefficient of each Q(i) was found little change along with the variation of composition and temperature.