PREPARATION OF LOW MOLECULAR WEIGHT POLY（GLYCIDYL METHACRYLATE） BY PHOTOPOLYMERIZATION

Low molecular weight poly（glycidyl methacrylate）s （PGMAs） were prepared by photopolymerization in ethyl acetate, with benzophenone （BP） as photoinitiator, and triethylamine （TEA） as hydrogen donor. The existence of semipinacol dormant end groups in PGMA was confirmed by FT-IR and ^1H-NMR, and the content of the semipinacol dormant groups was determined quantitatively by ^1H-NMR measurement. The effects of various thctors, such as reaction time, BP concentration and monomer concentration on the synthesis of the polymers were investigated systematically. The molecular weights of the polymers were also investigated with GPC. It is shown that increasing BP concentration and decreasing irradiation time and monomer concentration led to a significant decrease of the molecular weights.     

SYNTHESIS OF BOWL-LIKE PARTICLES BY EMULSION POLYMERIZATION AND RELEASE BEHAVIOR OF SOLVENT FROM THE PARTICLES

Poly(styrene-glycidyl methacrylate) particles having bowl-shaped hollow structures were synthesized by swollen seed emulsion polymerization. The PS emulsion synthesized through soap-free emulsion polymeri:ation was swollen by toluene, and then the mixture of second monomers was added under polymerization condition So a thin shell of poly(styrene-glycidyl methacrylate) cross-linked by triethylene glycol diacrylate was formed around the swollen PS particle. The bowl-shaped particles were obtained after the collapsing of the thin shell when the toluene emanated from the particles, but the shapes were effected by the degrees of cross-linking. The shape of the particles was observed by SEM. The release behavior of solvent from the particles was examined by TG     

水菱钇型碳酸钕的形成及聚甘油脂肪酸酯对结晶的影响

Amorphous Neodymium carbonate was prepared by the precipitation reaction of neodymium chloride with ammonium bicarbonate in solution, and then aged at 60 ℃ to form crystalline neodymium carbonate. The feed molar ratio of n_(NH4HCO3)/n_(NdCl3 was 2.5, and the precipitation was carried out with or without addition of polyglyceryl fatty acid ester (PGFAE). The phase type and morphology of crystalline neodymium carbonates were examined by XRD and SEM, and the effect of PGFAE on the crystallization speed was investigated by volume change in deposit layer and in situ pH determination. The content of neodymium and chloride in crystals was analyzed, and the crystallization reaction or crystal growth characteristics were discussed. It was found that all the crystalline neodymium carbonates were tengerite type, and contained less crystalline water and chloride than that of lanthanite type neodymium carbonate crystallized at room temperature, which is beneficial to the production of neodymium carbonate with higher neodymium and lower chloride content. The addition of PGFAE not only could eliminate the foam formed during precipitation, but also could shorten crystallization time, and form large radiative-like shape conglomeration by the irregulative linkage of one dimension needle crystals. It is also suggested that the morphology and the chloride content of neodymium carbonate were dependent on the structure and crystal growth characteristics.     

生产甘油的探索性试验

生产甘油的探索性试验.     

高效液相色谱法测定饮料中糖、甘油和乙醇

研究了高效液相色谱法测定饮料中糖、甘油和乙醇的方法。饮料样品用WatersSep Pak C18固相萃取小柱预分离 ,以WatersSugar Pak 1钙型阳离子交换柱为固定相 ,0 .0 5 g·L- 1ED TA钙钠水溶液为流动相 ,示差折光仪为检测器 ,一次进样测定饮料样品中的糖、甘油和乙醇。检出限在微克级 ,RSD在 0 .6 8%～ 2 .1%之间 ,标准回收率在 96 %～ 10 7%之间。方法用于几种饮料样品的测定 ,结果满意     

Pb促进的Pd/γ-Al2O3催化剂上H2O2氧化甘油反应

制备了Pd含量为1 wt%、不同Pb/Pd摩尔比的γ-Al2O3负载Pd-Pb双金属催化剂,并用于常压、45°C和pH =11条件下H2O2氧化甘油反应中.催化剂的形貌和分散度采用扫描电镜-X射线电子散射谱和透射电镜进行了表征;双金属催化剂中合金相用X射线光电子能谱进行了验证.单金属Pd催化剂上反应结束后甘油转化率为19%,但随着Pb的加入甘油转化率增大到约100%.所制四个不同Pb/Pd原子比的双金属催化剂PdPb0.25, PdPb0.50, PdPb1.00和PdPb1.60均可氧化甘油至二羟基丙酮(DIHA),反应结束后DIHA选择性分别可达59%,58%,34%和25%.     

均相介质中脂肪酶催化沙丁鱼油甘油解反应的动力学研究

多不饱和脂肪酸(PUFAs)的生产多集中在酶催化,与无机催化相比,酶催化具有定向性和更温和的反应条件,因而酶催化制取多不饱和脂肪酸的路线在最近几年引起人们极大的兴趣。本文以优化量的叔丁醇为有机溶剂,研究了脂肪酶Lipozymeò435催化沙丁鱼油甘油解反应生成PUFA (多以甘油一酯或二酯(DAGs, MAGs)的形式存在)。首先分析了反应系统的传质影响,考察了脂肪酶载量、温度和进料浓度等因素的影响。采用一个基于甘油酯甘油解和水解这对可逆基元反应的半经验动力学模型,成功地关联了实验的动力学数据。结果表明,温度为323 K,甘油与油的摩尔比为3：1时,生成的MAG可达84 wt%以上。还考察了其他甘油解体系,并在MAG收率、反应速率和动力学参数意义等方面进行了比较。     

Entanglement of a Five-Qubit Heisenberg XX Chain in a Magnetic Field

We calculate the eigenvalues and eigenvectors of a five-qubit isotropic Heisenberg model in an external magnetic field, and give analytical results for the concurrence of two nearest-neighbor qubits. A magnetic field can eliminate degeneration and change the ground state of the system. Therefore increasing the value of the magnetic field can induce entanglement in a certain range both for the antiferromagnetic and ferromagnetic case.     

无溶剂体系中脂肪酶催化合成单甘酯的研究

以自制铜绿假单胞菌脂肪酶为催化剂,通过无溶剂法棕榈油甘油解反应催化合成了单脂肪酸甘油酯,实验结果表明：适宜加酶量为500u/g棕榈 油,甘油相适宜水含量为3％－4．5％,适宜加酶量为500u/g棕榈油,甘油与棕榈油的摩尔比为（2．0－2．5）：1,最佳反应温度为38－42度,在此温度区间内适宜反应时间为24h,临界反应温度为44度,程序降温和批次加酶更有利于反应,产物中单甘酯含量可增大10－20％,实验条件下反应48h后单甘酯含量可达65％,脱酶后达77％。     

基于移动增值业务的电信服务链建模研究

以高速发展的移动互联网为背景,研究了由一个服务提供商和一个电信运营商组成的移动增值业务电信服务链商业模式.考虑了电信运营商促销对于移动增值业务市场需求的影响,构建了电信运营商主导的移动增值业务博弈模型,给出了不同合作模式情形下服务提供商和电信运营商的最优决策.