溶剂热法制备纳米氧化镍及其表征

以乙酰丙酮镍、油酸、油胺为原料，十八烯为溶剂，聚乙烯吡咯烷酮为表面活性剂，采用溶剂热法，在不同反应条件制备了纳米级氧化镍材料.通过X射线衍射（X-ray diffraction，XRD）、透射电子显微镜（Transmission electron microscope，TEM）、紫外-可见光吸收光谱（Ultraviolet-visible spectroscopy，UV-Vis）光谱分析以及塔菲尔（Tafel）测试考察了反应物比例、保温时间、表面活性剂（PVP）、油胺的量对产物微结构、粒径、形貌、光学以及电化学活性性能的影响.实验结果表明：在反应物n[Ni（acac）₂]∶n（OA）=1∶2、添加剂PVP质量分数为1.66%、油胺物质的量为30 mmol、200℃下保温8 h时，可获得粒径约为30～40 nm纯相氧化镍，具有最佳电化学活性，交换电流密度为J₀=1.23×10^-2 mA·cm^-2.     

高温下淀粉的凝胶化作用

凝胶化作用是淀粉及改性产品生产过程中存在的一种现象。淀粉凝胶化作用的结果导致了在其产品中产生了只溶胀但不溶解的颗粒,从而影响了淀粉产品的整体性能。文章初步探讨了淀粉在高温成型过程中凝胶化作用的方式和起因。结果表明,淀粉浆料在高温成型过程中所产生的凝胶团粒是淀粉不完整的凝胶化作用的结果,足量的水分和高温是形成较多的凝胶化淀粉颗粒的原因。     

Ni－La_2O_3复合镀层的氧化行为及机制

通过对金属镍、镍镀层及Ｎｌ－Ｌａ２ｏ３复合愤层于９００℃、１０００℃时的恒温氧化实验，发现Ｎｌ－Ｌａ２Ｏ３复合镀层的氧化行为明显改善。高分辨电子显徽镜（ＨＲＥＭ）的观测研究表明，Ｎｉ－Ｌａ２Ｏ３复合铰层氧化时，纳米尺寸的ｋａ２Ｏ３颗粒掺人到氧化层中，形成了ＮｉＯ－Ｌａ２Ｏ３复合氧化物层；在氧化层晶界发现了异常原子排列的新现象。由此认为，Ｎｉ－Ｌａ２Ｏ３复合镀层抗高温氧化性能的提高，主要归因于小尺寸的纳米颗粒可微量溶解，成为Ｌａ（３＋）的晶界们聚“源”，阻止Ｎｉ（２＋）的短路向外扩散，从而改善了氧化层的微观结构和生长机制。     

Electrooxidation Mechanism of Methanol at Pt-Ru Catalyst Modified GC Electrode in Electrolytes with Different pH Using Electrochemical and SERS Techniques

The electrochemical and in-situ surface-enhanced Raman spectroscopy （SERS） techniques were used to investigate the electrooxidation behavior of methanol in acidic, neutral and alkaline media at a Pt-Ru nanoparticle modified glassy carbon （Pt-Ru/GC） electrode. The results showed that methanol could be dissociated spontaneously at the Pt-Ru/GC electrode to produce a strongly adsorbed intermediate, CO. It was found that CO could be oxidized more easily in the alkaline medium than in the acidic and neutral media. The peak potential of methanol oxidation was shifted from 0.663 and 0.708 V in the acidic and neutral media to -0.030 V in the alkaline medium, which is due to that the adsorption strength of CO on the Pt surface in the alkaline medium is weaker than that in the acidic and neutral media. The final product of the methanol oxidation is CO2. However, in the alkaline medium, CO2 produced would form CO3^2- and HCO3^- resulting in the decrease in the alkaline concentration and then in the decrease in the performance of DMFC. Therefore, the performance of the alkaline DMFC is not Stable.     

新型高活性催化剂乙烯气相聚合的研究（Ⅱ）——改性剂,预聚…

研究了新型高活性乙烯气相聚合催化剂ＴｉＣｌ４／ＭｇＣｌ２／ＺｎＣｌ２／ＳｉＣｌ４醇／Ａｌ（ｉ－Ｂｕ）３体系中不同醇、不同Ｃ２Ｈ５ＯＨ／Ｔｉ摩尔比和正丁醚对聚合反庆及产物颗粒形态的影响，研究了预聚合反应及乙烯气相聚合反应规律，用扫描电镜和图象分析对催化剂、预聚物和聚合产物的形态和颗粒分布的研究表明：新型高活性催化剂和经预聚合制得的乙烯气相聚合物的颗粒形态类似球形，颗粒长短轴比值和大小粒径比值相近。     

城市土壤不同颗粒中重金属的分布及其对人体吸入重金属的影响

采集了9个不同质地的城市土壤,按颗粒大小分为6个粒级,分别测定了4种重金属(Cu、Cd、Co和Pb)的全量和有效态含量。结果表明,细颗粒中重金属有明显的富集,其中<0.002 mm粒组的重金属含量约为土壤的1.57~13.95倍。有效态重金属占其总量的比例一般是0.250~0.125 mm和0.125~0.050 mm粒组高于其它粒组。质地对重金属在不同颗粒中的分配有很大的影响;虽然重金属含量一般是质地较黏的土壤高于质地不黏的土壤,但砂质土壤中细颗粒组分中的重金属的含量却一般要高于黏质土壤的相应粒组。因此,在相同的重金属含量条件下,砂质土壤对人体的潜在影响要远高于黏质土壤。     

Protein Adsorption onto Nanosized Hydroxyapatite Particles for Controlled Drug Release

Nanosized hydroxyapatite(nsHAp) was synthesized to examine its possibility as a controlled release carrier of protein. To achieve effective protein release from nanosized hydroxyapatite, the study of the adsorptive properties of protein on nsHAp and different influence parameters such as pH, calcium, and phosphate concentrations during the adsorption process is necessary. Ovalbumin(OVA) was selected as the model of growth factors. The results show that the amount of OVA adsorbed onto nsHAp in acetic buffer(pH=3.6) is more than that in acetic buffer(pH=5.6) because of the electric interaction. The amount of OVA adsorption in phosphate buffer solution(PBS) is smaller than that in acetic buffer because of surface complexation and surface hydroxylation. The presence of Ca2 dramatically increases the adsorbed amount of OVA in acetic buffer on maintaining the same pH. Meanwhile, the release kinetics of OVA adsorbed onto nsHAp(nsHAp-OVA) was also examined. The amount of released OVA in PBS(pH=5.6) was significantly smaller than that released in solution of pH=7.0. All the results suggest that nanosized hydroxyapatite particles could be successfully used as controlled released carrier of protein.     

颗粒性甲烷单加氧酶的电子供体研究

从甲基弯菌M ethylosinus trichosporium IMV3011的膜中分离出颗粒性甲烷单加氧酶（Particulate MMO,Pmmo）t和NADH脱氢酶，只有当两者同时存在，并添加去垢剂解离膜组分时，NDAH才能为pMMO提供还原当量，对苯二酚能够在整细胞和膜水平代替NADH作为PMMO的电子供体，对于纯化的PMMO，对苯二分配仍是有效的电子供体，而NADH却是无效的电子供体。在NADH脱氢酶存在下，NADH可将对苯醌还原为对苯二酚，纯化过程中，采用对苯二酚作为PMMO活性分析时的电子供体，不必共纯化NADH脱氢酶，且有利于对PMMO活性中心进行深入研究。     

反相微乳液法制备棒状羟基磷灰石纳米粒子

在(Tritonx-100 Tween 80)，环己烷，(正己醇 正丁醇)，0．5mol／L Ca(NO3)2水溶液反相微乳液体系中，采用滴加0．3mol／L(NH4)2HPO4水溶液的加料方式成功制备出直径在20～25nm，长度在28～64nm的棒状羟基磷灰石纳米粒子。通过对(Triton X-100 Tween 80)，环己烷，(正己醇 正丁醇)／0．5mol／L Ca(NO3)2水溶液三元相图及水溶液反应机理的分析，确定了最佳反相微乳液组成；研究了HLB值和表面活性剂用量对羟基磷灰石颗粒大小的影响。实验结果表明，最佳反相微乳液组成为：47．6(wt)％的环己烷、37．4(wt)％的表面活性剂和助表面活性剂、15(wt)％0．5mol／L的Ca(NO3)2水溶液。