2-苯基-4-硒唑甲醛的合成研究

以硒代苯甲酰胺、1,3-二氯丙酮为起始原料,环化得到2-苯基-4-氯甲基硒唑;所得氯甲基硒唑在碱性条件下通过二甲亚砜氧化得到2-苯基-4-硒唑甲醛。较佳的氧化条件：2-苯基-4-氯甲基硒唑10mmol,DMSO 50mL,NaHCO3 20mmol,KI 5mmol,温度100℃,反应时间6h;两步总收率可达63．8％。     

Micellar thin-layer chromatographic separation of heavy metal cations: Effect of organic and inorganic additives on migration behavior

The migration behavior of heavy metal cations on cellulose layers using aqueous micellar, hydro-organic, and water-organic-surfactant mobile phases was investigated. Anionic, cationic, and nonionic surfactant systems were examined over a 0.001–5% concentration range. Brij-35, a nonionic surfactant capable of forming charged complexes with some metal ions, was identified as the best surfactant. The effect of the presence of organic additives, such as dimethylsulfoxide, dimethylformamide, methanol and acetone, on the mobility of metal ions was also studied. Acetone was found to be the most effective additive at 10% concentration with 3% Brij. Quantitative determination of UO₂ ²⁺ by spectrophotometry after preliminary thin-layer chromatographic (TLC) separation from Fe³⁺ and Hg²⁺ was also performed. A maximal recovery of 93% was obtained. This TLC method is rapid, with development times averaging 2 min.     

溶剂对FOX-7晶体相变和热性能的影响

采用重结晶法在二甲基甲酰胺(DMF)/H2O、二甲基亚砜(DMS)O/H2O和N-甲基吡咯烷酮(NMP)/H2O等不同溶剂体系中得到FOX-7晶体,用扫描电子显微镜(SEM)测试晶体的形貌、变温X-射线粉末衍射(XRD)分析晶型和相变、差示扫描量热仪(DSC)测试其热性能。结果表明,不同溶剂重结晶得到的FOX-7晶体形貌有较大差别,在DMSO/H2O溶剂中得到的晶体质量要优于其他两种;3种溶剂中得到FOX-7晶体的晶型和相变过程相同,即常温下FOX-7的晶型为α晶型,在120℃时,FOX-7完成α→β相变,至185℃时,完成β→γ相变;重结晶的FOX-7晶体5s爆发点温度提高了4~9℃,说明热稳定性增强。     

O-2,4-二氯苯甲基羟胺盐酸盐的合成

以丁酮肟和2,4-二氯氯苄为原料合成了O-2,4-二氯苯甲基丁酮肟醚,再用盐酸水解得到了O-2,4-二氯苯甲基羟胺盐酸盐。文章系统研究了反应温度、不同溶剂、溶剂含水量等各种实验因素对O-2,4-二氯苯甲基丁酮肟醚合成的影响,研究了盐酸浓度、原料配比等因素对O-2,4-二氯苯甲基丁酮肟醚水解工艺的影响。两步收率最高分别为94.5%和85.0%。产物熔点为167.7～169.9℃。     

Investigation of dispersion states and rheological properties of SPI in the DMSO/urea

Dimethylsulfoxide (DMSO)/urea were chosen as a hybrid solvent system to dissolve soy protein. The dispersion status and rheological properties of soy protein isolates (SPI) in the DMSO/urea were studied. The result showed that SPI has relatively high solubility in DMSO/urea blend system and urea served as a key factor of dissolving SPI in the system. SPI in the DMSO/urea hybrid system exhibited different dispersion statuses with increasing of SPI content. The SPI dispersions in the DMSO/urea presented shear thinning or pseudoplastic behavior. The pseudoplastic behavior, the degree of non‐Newtonian flow and the extent of structuralization of SPI dispersion system with increasing SPI content were discussed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008.     

残余溶剂DMSO对PAN纤维结构及热性能的影响

在PAN／DMSO湿法纺丝体系中，改变水洗条件，得到含有不同DMSO含量的聚丙烯腈原丝．通过先学显微镜、X射线衍射、DSC和TG等分析测试手段，研究了残余溶剂二甲基亚砜(DMSO)对PAN纤维结构及热性能的影响。在纤维低温热处理过程中，原丝中痕量DMSO的存在，可以改变纤维的截面形状、破坏纤维的晶态结构，并使纤维的热稳定性降低。     

Determination of the Diffusion Coefficient of H<Subscript>2</Subscript>O in Polyacrylonitrile Fiber Formation

An H₂O/dimethyl sulphoxide (DMSO) mixture was used as the coagulation bath of a wet-spun process. The diffusion coefficient of H₂O in the protofibers prepared by acrylonitrile homopolymers was determined. It was found that the diffusion coefficient of H₂O in the protofibers prepared by homopolymers synthesized by solution polymerization was highest compared with those of homopolymers synthesized by H₂O/DMSO mixture suspension polymerization and aqueous suspension polymerization. With an increase of polyacrylonitrile concentration in the dope, the diffusion coefficient of H₂O decreased continuously. The diffusion coefficient of H₂O increased along with the bath temperature, but the changes of diffusion coefficient values were less prominent as the temperature went beyond 60^○C. When the DMSO concentration in the coagulation bath was 55%, the value of the diffusion coefficient of H₂O was minimal. The diffusion coefficient of H₂O increased with increasing jet stretch minus ratio. When the protofiber radius was increased, there was a corresponding increase of the diffusion coefficient of H₂O.     

The correlation between skin-care effects and phytochemical contents in Lamiaceae plants

In this study, well-known skin-care functional parameters were used, including UV absorption, DPPH-scavenging, NO-production-inhibition, tyrosinase-inhibition activity and anti-Staphylococcus aureus activity to measure the effects of the 70% acetone-extracts form 28 species of Lamiaceae plants. Further, the phytochemical contents were explored by total phenol (TP), total flavone (TF) and total coumarin (TC). The correlation between the skin-care effects and the phytochemical contents was analysed by non-parametric correlation analysis. Amongst the 70% acetone-extracts, Origanum majorana displayed the strongest DPPH-scavenging and tyrosinase-inhibitory effects and the richest phenol content. Based on the statistics results, the phytochemical contents were related with those parameters, such as: DPPH-scavenging effects vs. TP (R = 0.542), TF vs. TP (R = 0.613), and NO-inhibitory vs. anti-bacterial activities (R = 0.767). Moreover, each genus of Lamiaceae had different properties of skin-care effects. Form our research works, the Lamiaceae is good resources to develop skin-care cosmetics.     

Cytotoxicity of titanium dioxide nanoparticles differs in four liver cells from human and rat

Titanium dioxide (TiO₂) nanoparticles (NPs) are the important nanoscale components of composites. Although TiO₂ NPs and their related nanocomposites have been widely used in industrial and medical applications, the adverse effects of TiO₂ nanomaterials have not been well studied. Here, we investigated the cytotoxicity of TiO₂ NPs in vitro using four liver cell lines: human hepatocellular carcinoma cell line (SMMC-7721), human liver cell line (HL-7702), rat hepatocarcinoma cell line (CBRH-7919) and rat liver cell line (BRL-3A). We checked cell viability, cell morphology, and the levels of reactive oxygen species (ROS) and glutathione (GSH) after TiO₂ exposure at varying concentrations (0.1–100 μg/mL) and different exposure periods of time (12–48 h). Compared to the NP-free control, all four cell lines exposed to TiO₂ NPs showed cytotoxicity in a dosage-dependent and time-dependent manner, which was associated with the changes of cell viability and cell morphology, increased intercellular ROS levels, and decreased intracellular GSH levels. Further, we observed that carcinomatous liver cells and human liver cells exhibited more tolerance to TiO₂ NPs exposure for 24 h, compared to normal liver cells and rat liver cells, respectively. The results indicate that the in vitro cytotoxicity induced by NPs should be assessed with great caution before the use of nanocomposites and that there is a need to standardize the cytotoxicity testing procedure of nanoscale components in composites when using different cell lines.