（NH_4）_2SO_4─NH_4Cl─NH_4HCO_3—H_2O体系在10

（ＮＨ＿４）＿２ＳＯ＿４─ＮＨ＿４Ｃｌ─ＮＨ＿４ＨＣＯ＿３—Ｈ＿２Ｏ体系在１０℃时的溶解度相图汪庆华，付鹤鉴，宋德镇，刘维铭，于海生（四川联合大学（东区）化学系成都６１００６４）关键词：溶解度相图，硫酸铵，氯化铵，碳酸氢铵在化工生产中，为了降低成本，...     

FeCl3-catalyzed propargylation of aromatic compounds with propargylic acetates

A new method for the synthesis of propargylated aromatic compounds is developed. The reaction was carried out at room temperature in the presence of a catalytic amount of FeCl₃ in acetonitrile, high product yields were obtained with excellent regioselectivity and the reaction proceeded smoothly without exclusion of moisture or air.     

环氧氯丙烷交联季铵化壳聚糖/聚砜复合纳滤膜的制备

将2-羟丙基三甲基氯化铵壳聚糖(HACC)的铸膜液与聚砜超滤膜进行复合,用环氧氯丙烷(ECH)交联,制备了一种新型荷正电复合纳滤膜.结果表明,该类膜呈复合结构,截留分子量为720;20℃时,膜的纯水渗透系数为12.6 L·h-1·m-2·MPa-1,对不同无机盐料液的截留的顺序由高到低为MgCl2,NaCl,KCI,MgSO4,Na2SO4,K2SO4.     

Heat capacities of aqueous mixed electrolyte solutions at high temperatures. Application of the Pitzer equations to the mixed system K−Na−Cl−SO4

Specific heats at constant pressure for the mixed system K/Na/Cl/SO₄ in H₂O have been obtained from heat content measurements by means of a drop calorimeter between 60 and 220°C over the salt concentration range 0.5–5m, with ionic strengths up to 7.5. Measurements have also been made on aqueous K₂SO₄ solutions in the same temperature range between 0.3 and 1.6m. The heat capacities of the quaternary system were represented using the semiempirical Pitzer equations neglecting the mixed interaction terms as a first approximation. A comparison of experimental with calculated data shows that the ability of this method to describe the system is satisfactory even at rather high concentrations, but only for solutions of low sulphate ion content.     

An electrochemical study for corrosion inhibition of iron by some organic phosphonium chloride derivatives in acid media

The inhibiting action of (chloromethyl) triphenyl phosphonium chloride (CTP), tetraphenyl phosphonum chloride (TP), triphenyl phosphine oxide (TPO), triphenyl (phenylmethyl) phosphonium chloride (TPM) and triphenyl phosphine (TPP) on the corrosion of iron in 1 M HCl solution was studied using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Experimental results revealed that CTP, TP, TPO, and TPM act as inhibitors for iron in acid environments, while TPP is an accelerator. These compounds are mixed-type inhibitors and the inhibition efficiency increased with increasing concentrations. Equivalent circuits of the investigated systems are suggested.     

An iron–organic polymeric smoke suppressant for poly(vinyl chloride)

The incorporation of a poly[ferrocene-1, 2 (1, 3: 1, 1′)diylmethylene] fraction with M?_n=2100 as a smoke suppressant additive into both unplasticized and di(2-ethylhexyl)phthalate-plasticized, calcium carbonate-filled poly(vinyl chloride) (PVC) compositions entails appreciable reductions in smoke evolution during combustion tests relative to unmodified formulations. Best results, with smoke density reductions in the range 25-80%, are obtained at the 3% loading level, with higher additive concentrations causing no further improvements. The findings of this study may have implications on the design of other polymeric engineering materials exposed to potential fire hazards.     

The palladium(0) Suzuki cross-coupling reaction as the key step in the synthesis of aporphinoids

We report a flexible approach to the total synthesis of 4,5-dioxoaporphines based on the palladium(0) catalyzed Suzuki cross-coupling of phenylboronic acids with sterically hindered 2-bromo phenyl acetates or bromo phenyl acetamides, followed by sequential bicyclization of biarylacetamides promoted by oxalyl chloride/Lewis acid. The reduction of 4,5-dioxoaporphines provides a chemoselective entry to aporphines, dehydroaporphines and 4-hydroxy-dehydroaporphines. A three-steps total synthesis for (±)-O,O′-dimethylapomorphine from readily accessible precursors is also reported.     

X-ray microanalysis of uterine epithelial cells in culture

The ionic composition of the uterine fluid, secreted by the endometrium, is of importance for fertilization and embryonic development. Little, however, is known about the ion transport mechanisms in the uterine epithelial cells. Because it is difficult to study ion transport in this tissue in situ, a method was developed to culture mouse uterine epithelial cells for X-ray microanalysis in the electron microscope, in order to allow the study of ion transport. Our data suggest the presence of a number of ion transport mechanisms in the cultured uterine epithelial cells. The cells appear to possess a ouabain-sensitive Na⁺---K⁺-ATPase, an amiloride-sensitive Na⁺---H⁺ antiporter, cAMP- and Ca²⁺-activated chloride channels, and volume-activated chloride efflux and influx mechanisms. In addition, chloride efflux can be stimulated by cholinergic and alpha-adrenergic agonists. Only a few of these mechanisms had been studied previously in the uterine epithelium.     

New results on the influence of the nature of the nucleophile in the stereospecific modification of poly(vinyl chloride)

The nucleophilic substitution reactions on poly(vinyl chloride) (PVC) with potassium 4‐acetamidothiophenolate, potassium 2‐naphthalenethiolate, and sodium 2‐mercaptobenzothiazolate have been undertaken in a cyclohexanone solution. The aim was to study, from a comparative point of view, the influence of nucleophile characteristics, in particular bulkiness, reactivity, and nucleophile polarity, on the reaction mechanisms by following the microstructural evolution with the degree of substitution of the same PVC sample with three types of nucleophile under the same experimental conditions. The quantitative microstructural analysis as a function of conversion has been followed by ¹³C NMR spectroscopy. Because of the steric hindrance and moderate reactivity of 2‐mercaptobenzothiazolate, the stereoselective nature of the reaction is enhanced, occurring via the meso‐racemic ( mr ) triad of mmr tetrad, inoperative in practice, unlike the other nucleophiles. This circumstance and the fact that the bulkiness of the nucleophile and interacting effects provide an enhancement of the molecular microstructure‐based mechanisms, such that glass‐transition temperature (T_g) varies with the degree of substitution, in all cases, along with the ratio between the extent to which mmr and rrmr structure intervene in the substitution reaction, thereby providing new and valuable information regarding the T_g–microstructure relationship. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6052–6060, 2004     

低剂量三氯化钐对实验性非胰岛素依赖型糖尿病大鼠胰岛的影响

观察了经腹腔注射低剂量三氯化钐（０．０５ｍｇ／ｋｇ）对链脲佐菌素引志的非胰岛素依赖型糖尿病（ＮＤＩＤＤＭ）大鼠胰岛形态和功能的影响。结果表明，三氯化钐治疗组糖耐量改善、血清胰岛水平长高、血清胰镐血糖素水平降低、平均单个胰岛面积和胰岛β细胞数量明显增多，肝细胞内糖原含量增多。提示低剂量三氯化钐对实验性ＮＩＤＤＭ大鼠有一定的治疗作用。