固定化多菌种发酵海藻酒的研究

采用PVA固定化酿酒酵母和产香酵母发酵海带，酿造海藻酒。对游离细胞与固定化细胞的分批发酵和连续发酵的动力学进行了研究并建立了相应的发酵动力学方程。实验结果表明：酿酒酵母和产香酵母最佳配比为4：1，发酵温度20℃，固定化细胞分批发酵和连续发酵凝胶粒的充填系数分别为0．25和0．5，游离混合细胞的发酵时间为7d，固定化细胞连续发酵稀释速率0．12/h，发酵时间为0．5d左右。经160d连续发酵实验，PVA固定化细胞粒子的机械强度良好。     

双甲基丙烯酸聚乙二醇酯的合成及光聚合反应

合成了一系列新型的具有光引发聚合反应活性的单体；不同分子量的聚乙二醇的双甲基丙烯酸酯。单体在紫外光引发条件下进行自由基聚合，生成交联的聚合产物。用＾１Ｈ－ＮＭＲ对单体进行了表征。用ＩＲ对单体和聚合物进行了分析，研究了双甲基丙烯酸二乙二醇酯的聚合反应动力学，测定了聚合活化能。     

Ni-Mo-W非负载型催化剂加氢脱硫性能的改进及结构探究

在共沉淀法制备三元(Ni-Mo-W)非负载型催化剂过程中加入聚乙二醇(PEG),采用XRD、BET及微反活性评价考察PEG的最佳相对分子质量及加入量,采用Py-IR,SEM,TEM等后续表征分析最佳条件下PEG对催化剂性质和脱硫活性的影响,采用XRD、LRS对Ni-Mo-W复合氧化物的结构进行深入探究。结果表明:在PEG的相对分子质量为600、加入量为Mo物质的量的20%时,催化剂对劣质柴油的脱硫率最高,可达99.8%;此条件下的Ni-Mo-W非负载型催化剂形态规整,活性组分分布均匀,相互间排列有序,孔隙最为发达,酸位得到充分暴露。合成的Ni-Mo-W复合氧化物是具有不同Mo、W配位的新型Ni基化合物,Ni-W构成主体及表层,内部填充部分主要由Ni-Mo构成。     

胶束分光光度法测定茶叶中微量铝含量

在pH=5.0的乙酸-乙酸钠条件下,铝-铬天青S-乙二醇形成三元配合物。测定在最的吸收波长为549 nm处,对浓度在0～7μg/mL范围内的铝标准溶液的吸光度进行测定,结果表明：三元配合物吸光度与铝标准溶液浓度有良好的线性关系,标准工作曲线回归方程为y=0.1519x-0.0371,线性相关系数R2=0.9956,相对标准偏差RSD为2.31%。该法操作简单,显色灵敏、稳定、精密度高。适用于茶叶中铝含量测定的要求。     

Influence of the polyethyleneglycol content on the properties of ethyleneglycolterephthalate/polyethyleneglycol terephthalate copolymers

The effect of the polyethyleneglycol (PEG) content on the properties of the ethyleneglycol terephthalate (EGT)/polyethyleneglycol terephthalate (PEGT) copolymers has been studied. The PEG content varied over a wide range (5-70% PEG). To obtain information on the solubility and on the thermal properties, the following methods: turbidimetry, differential scanning calorimetry (DSC), thermogravimetry and differential thermogravimetry (TG, DTG) have been used. The turbidimetric characteristics are dependent on composition copolymers. The incorporation of increasing amount of PEG 4000 in EGT/PEGT copolymers has a pronounced effect on the properties: increases viscosity and solubility of copolymers, decreased glass transition, cold crystallization and melting temperatures and also decreased crystallization and melting heat. These changes are desirable for better processing of these copolymers comparatively with PET in products with higher elasticity and hydrophilicity. It must be take into account, however, that above 20 wt% PEG the copolymers the thermal stability is significantly affected.     

Stoichiometric and nonstoichiometric polyelectrolyte complex of chitosan and polyethyleneglycol‐monosuccinate: Preparation and characterization

Stoichiometric and nonstoichiometric polyelectrolyte complex (PEC) was prepared with polyethylene glycol‐monosuccinate (PEGMS), and chitosan (CS). A series of PEGMS were synthesized by a 1 : 1 mol ratio between PEG and succinic anhydride. Then, the novel PEC was prepared by a various mole reaction of the above synthesized PEGMS and CS. The physicochemical properties of the synthesized PEC was characterized by using elemental analysis, FTIR, ¹H, and ¹³C nuclear magnetic resonance, dissolution behavior, and phase transition phenomenon. Furthermore, some properties of the PEC obtained were analyzed by UV‐Visible spectrometry, wide‐angle X‐ray diffraction, differential scanning calorimeter, scanning electron microscope, and estimated solubility, and cell viability assay, respectively. It was found that the observed FTIR, ¹H, and ¹³C‐NMR data was in good agreement with the chemical structure of the prepared PEGMS and PEC. The dissolution behaviors of nonstoichiometric PEC were found to depend on the pH of the solution as well as on the PEGMS/CS composition. The study of MTT assay suggested that the viability of HepG2 human hepatoblastoma cell on PEC were increased significantly in accordance with mole ratio of CS. As the results, the obtained several product is a useful intermediate, which permits further chemical modification for the amino group of CS and may have potential applications in biocompatible or cosmetic systems. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Nanofiltration Separation of Aqueous Polyethyleneglycol – Salt Mixtures

To investigate nanofiltration (NF) separation for recycling polyethylenglycol (PEG) from an ion partition process using an aqueous two-phase system, fractionation performance of five different NF membranes (NF270, SR3, SR100, SR2, and BW30) with solutions of NaNO₃, KClO₄, and PEG 4000 in water comprising various mixtures were studied. PEG rejections and salt passage were analyzed and explained based on size exclusion as well as electrostatic interactions. The highest permeate flux at high rejection of PEG as well as the lowest salt rejections were obtained with SR2 and NF270 membranes. Similar salt rejections were observed for mixed solute solutions and complex mixtures, all following this trend: SR3 > NF270 > SR2. The PEG rejections were well above 95%. This study also revealed that high salt passage of above 90% could be achieved with the same NF membrane only by unstirred conditions through concentration polarization mechanism; however, at the expense of low flux, especially with high PEG concentrations.     

低黏度光敏预聚物聚乙二醇二缩水甘油醚二丙烯酸酯的合成

以N,N-二甲基苯胺为催化剂、对羟基苯甲醚为阻聚剂,利用聚乙二醇二缩水甘油醚(PEGDE)和丙烯酸为两种主要原料合成了一种低黏度光敏预聚物——聚乙二醇二缩水甘油醚二丙烯酸酯。研究了反应温度、阻聚剂、催化剂用量这些因素对其反应的影响,结果表明优化的合成反应条件是温度90～105℃、m(催化剂)：m(PEGDE)=(0．007～0．009)：1、m(阻聚剂)：m(PEGDE)=(0．002～0．004)：1。同时,把产物作为光敏预聚物配成光固化涂料对其光固化膜进行了性能测试,其结果表明它的光固化膜较双酚A型环氧丙烯酸酯作为光敏预聚物配成涂料的光固化膜柔韧性好。     

Functional bioengineering copolymers. II. Synthesis and characterization of amphiphilic poly(N-isopropyl acrylamide-co-maleic anhydride) and its macrobranched derivatives

Radical-initiated copolymerization of N-isopropyl acrylamide (NIPA) with maleic anhydride (MA) and macromolecular reactions of synthesized poly(NIPA-co-MA) with polyethyleneglycol (PEG with a methoxy chain end and molecular weight of 2000 g mol⁻¹) and polyethyleneimine (PEI with molecular weight of 2000 g mol⁻¹) have been studied as a way to obtain new reactive amphiphilic water-soluble polymers potentially useful as carriers for gene delivery. Structure, composition and thermal behaviour of synthesized copolymers and their macrobranched architectures are determined by FTIR, ¹H and ¹³C NMR spectroscopy, elemental (N content) and chemical (acid number) analysis and differential scanning calorimetry, differential thermal and thermal gravimetric methods. It is shown that synthesized copolymers with given composition have low critical solution temperature (LCST) in the range of 30.2-46.4 °C at pH values of 4.0-7.4, which suggest the possibility of their biomedical applications.     

聚乳酸/聚乙二醇/SiO2杂化薄膜的制备及性能研究

以正硅酸乙酯、聚乳酸与聚乙二醇为主要原料，采用溶胶-凝胶法在玻璃衬底上制备有机与无机杂化薄膜，研究了制备条件对薄膜性能的影响。结果表明：所制备的薄膜与衬底有很好的附着力；在380-800nm波段范围，镀有薄膜的玻璃对光的平均透过率在92％以上，且不需要光照就能长时间保持超亲水性达20天以上；pH值及溶胶陈化时间是影响薄膜亲水性的重要因素。