带功能基的全氟烷基乙烯基醚的研究——3、四氟乙烯与-7,7-二氯-3-氧杂全氟庚烯-1的共聚反应及共聚物的转化

 研究了二个新的全氟烷基乙烯基醚7,7-二氯-3-氧杂全氟庚烯-1(M_0)和10,10-二氯-3,6-二氧杂全氟5-甲基癸烯-1(M₁)-与四氟乙烯(TFE)的共聚反应,聚合物的性质,并测定了TFE-M₀竞聚率。竞聚率的测定证明M₀较其它已报道的全氟烷基乙烯基醚的聚合活性都大。TFE-M₀共聚物通过化学反应可转化成相应的全氟羧酸甲酯树脂。     

Pt3Co核-Pt壳型纳米粒子的制备及磁性

Pt₃Co alloy nanoparticles were prepared by the reduction of H₂PtCl₆ and Co(OOCCH₃)₂ using NaBH₄ as a reducing agent. The Pt₃Co core-Pt shell nanoparticles (Pt₃Co@Pt) were synthesized using hydrogen absorption reduction and characterized by plasma-atomic emission spectrometry (ICP), transmission electron microscopy (TEM), X-ray diffraction (XRD) and SQUID magnetometer. The results show that average size of Pt₃Co@Pt nanoparticles is 3.6 nm with a standard deviation of 0.9 nm. Heating Pt₃Co nanoparticles in air at 700 ℃ for 1 h, Co in Pt₃Co nanoparticles was oxidized to Co₃O₄ and CoO; while no oxidation tendency was detected for Pt₃Co@Pt nanoparticles. The crystallize structure of Pt₃Co@Pt changed from the face centered cube (fcc) to the face centered tetragonal (fct) after the heating treatment. The coercivity of the heated Pt₃Co@Pt reached to 276 Oe at room temperature.     

KPS—CuSO4—Na2SO3参与的无皂液聚合

研究了MMA-St在氧化还原引发剂KPS-CuSO_4-Na_2SO_3存在下的快速无皂乳液聚合.当[MMA]=0.51mol/L、[St]=0.49 mol/L、70℃对,在[KPS]=2.77×10~(-3)mol/L、[CuSO_4]=1.50×10~(-5)mol/L、[Na_2SO_3]=2.77×10~(-3) mol/L条件下反应100min,转化率大于90％;讨论了胶乳的分子量及其分布;求出了聚合反应活化能E_a=81.6 kJ/mol和聚合反应速率常数k_p=321.9 L/mol·s.     

Dynamic capillary coatings with zwitterionic surfactants for capillary isoelectric focusing

The use of surfactants as additives was demonstrated for the first time in capillary isoelectric focusing (CIEF) to dynamically modify the surfaces of bare fused silica capillaries. These surfactants were zwitterionic sulfobetaines: dodecyldimethyl (3-sulfopropyl) ammonium hydroxide (C12N3SO3), hexadecyldimethyl (3-sulfopropyl) ammonium hydroxide (C16N3SO3) and coco (amidopropyl)hydroxyldimethylsulfobetaine (Rewoteric AM CAS U). They were added directly to the protein-ampholyte mixture, and remained in the capillary during isoelectric focusing and mobilization. The C16N3SO3 and CAS U coatings were shown effective in CEF. Separation of seven IEF protein standards was obtained, with significantly improved resolution compared to that from an uncoated silica capillary. The effect of these surfactants on the electroosmotic flow (EOF) in CIEF was determined. CAS U was effective in suppressing the EOF at neutral and alkaline pH conditions, C16N3SO3 was effective in suppressing EOF at acidic and neutral pH conditions. C12N3SO3 however had little effect on the EOF. The pH gradients formed inside these surfactant coated capillaries were recta-linear at pH 6 to 9 (R2 approximately equal to 0.99). Reproducibility of migration time and peak area was determined. For all three coatings, the migration time standard deviations were less than 1.6 min, and the relative standard deviations of area were below 10%. The protein recovery in the CAS U-modified capillary was quantitative or near-quantitative for five of the seven proteins studied.     

3-(2-羟基苯基)-5-苯基-6-乙氧羰基-2-环己烯酮的合成与晶体结构

合成了3-(2-羟基苯基)-5-苯基-6-乙氧羰基-2-环己烯酮.通过元素分析、红外光谱、紫外光谱、核磁共振氢谱和质谱对其组成和结构进行了表征.利用X射线衍射分析方法测定了它的晶体结构.该化合物的晶体属单斜晶系,空间群P21/c,a=1.41946(17)nm,b=0.58445(7)nm,c=2.1756(3)nm,β=104.795(2)°,V=1.7450(4)nm3,Z=4,Dc=1.280 g·cm-3,F(000)=712,μ=0.088mm-1,R1[I＞2σ(I)]=0.0627,wR2[I＞2σ(I)]=0.1484.晶体结构测定结果表明化合物分子中的环己烯部分为半椅式构象,分子间通过氢键形成具有16元环的二聚体.     

Nitration Reaction Catalyzed by Horseradish Peroxidase in the Presence of H2O2 and NaNO2

The enzymatic nitration of phenol and m-cresol catalyzed by horseradish peroxidase was studied in the presence of H2O2 and NaNO2. The results showed that the nitration products of phenol were 2-nitro and 4-nitrophenols. There was also a small amount of by-products of hydroquinone and catechol. The influences of various reaction parameters, including pH, organic solvent type, and concentrations of NaNO2 and H2O2, on the nitration products were investigated. The yields of 4-nitrophenol and 2-nitrophenol were 14% and 12%, respectively. The nitration products of m-cresol were 4-nitro-m-cresol and 6-nitro-m-cresol, and the yields of 4-nitro-m-cresol and 6-nitro-m-cresol were 19% and 30%, respectively.     

锂离子二次电池电解质材料LiPF6的制备及表征

0引言 液态锂离子电池自1990年开发成功以来,由于具有比能量高、工作电压高、应用温度范围宽、自放电率低、循环寿命长、无污染、安全性能好等许多独特的优势[1],所以其发展前景十分广阔.目前液态锂离子二次电池中开发使用的无机阴离子导电盐主要有LiClO4、LiPF6、LiAsF6等,但LiClO4为强氧化剂,使用不安全而不宜用于电池,LiAsF6虽然性能颇佳,但有毒且价格较贵,故也不宜广泛使用.LiPF6被认为是目前较合适的电解质[1],但其制备困难,价格较贵,且目前报道的合成方法也多是以HF为介质[2～5].本文作者以PF5和LiF为原料在CH3CN溶剂中简单有效地合成了高纯LiPF6,并通过在手套箱中制样的方法对目标产物进行了红外、热重和X射线衍射分析,给出了LiPF6的红外光谱图、热重分析数据和X射线衍射图.     

丙烯酸酯和甲基丙烯酸酯基团转移共聚研究

研究了三种丙烯酸酯分别和四种甲基丙烯酸酯的基团转移共聚，用１Ｈ ＮＭＲ法测定共聚物组成，扩展的Ｋｅｌｅｎ Ｔｕｄｏｓ法测定竞聚率，结果为γＭＡ＝９２３、γＭＭＡ＝００６；γＥＡ＝１４１５、γＭＭＡ＝００１；γＢＡ＝７５１、γＭＭＡ＝００２；γＭＡ＝１４４１、γＥＭＡ＝００１；γＭＡ＝１３９６、γＢＭＡ＝０２３；γＭＡ＝８６６、γｉ ＢＭＡ＝００８，表明基团转移聚合同阴离子聚合有明显的相似之处．     

东太平洋深海锰结核的化学元素研究

用ICP-AES法测定了东太平洋深海锰结核样品中二十多种主，次及微量元素，结果表明，表面瘤状和表面光滑两种类型锰结核的化学元素含量有较明显的区别，如表面光滑的锰结核TiO2含较高，而表面瘤状的锰结核Mn/Fe之值较高等。     

立方介孔相含钕氧化硅的合成与表征

以十六烷基三甲基溴化铵为结构导向剂，通过水热法合成了具有立方结构的含钕Nd-MCM-48介孔分子筛材料。XRD和TEM测试表明当n_Nd/n_Si<0.05时可以获得典型的长程有序介孔立方结构相，随n_Nd/n_Si比的增加，晶胞参数的增大和红外吸收光谱(FT-IR)的变化为Nd进入介孔分子筛骨架中提供了有力证据。N₂吸附-脱附实验给出了其BET表面积为1 195 m²·g^-1，BJH平均孔径为3.6 nm。紫外-可见漫反射光谱(UV-Vis)证明钕氧形成一种八面体结构。X射线光电子能谱(XPS)进一步证明钕主要以三价形式存在于立方介孔分子筛骨架中。