Preparation of self-assembled cholesterol modified pullulan nanopaticles

的:经琥珀酸间隔臂将胆甾醇连接到普鲁兰分子链上,对普鲁兰多糖进行疏水改性,获得不同取代度的胆甾醇基-普鲁兰(cholesterol-modified pullulan,CHSP)改性材料,并研究CHSP材料在水中的自组装性质。方法:利用1-乙基-(3-二甲基氨基丙基)碳酰二亚胺盐酸盐(EDC)和4-二甲氨基吡啶(DMAP)催化琥珀酰胆甾醇(cholesterol succinate,CHS)与普鲁兰多糖反应,将琥珀酰胆甾醇接枝在普鲁兰分子链的羟基上,得到疏水改性的普鲁兰多糖衍生物。应用傅立叶红外光谱仪(Fourier transform infrared spectroscopy,FT-IR),核磁共振仪(proton nuclear magnetic resonance,1H-NMR)对产物进行表征。利用透析法制备自组装纳米球。通过透射电镜(transmission electron microscopy,TEM),动态激光粒度分析仪(dynamic laser lightscattering,DLS)表征了纳米粒的形态和粒径。以芘为荧光探针,通过荧光检测分析,测定CHSP的临界胶束浓度(critical... 【英文摘要】 Objective:To synthesize cholesterol-modified pullulan(CHSP) conjugates and to preparate self-assembled nanoparticles.Methods:The cholesterol-modified pullulan(CHSP) was prepared by the reaction of pullulan and cholesterol succinate(CHS) in DMSO,using EDC and DMAP as catalysts.The polymer structure was confirmed by the Fourier transform infrared spectroscopy(FT-IR) and proton nuclear magnetic resonance(1H-NMR).The self-assembled nanoparticles were analyzed by transmission electron microscopy(TEM),dynamic las...国家重大科学研究计划项目(2006CB933300);; 博士点基金(20060023050

选择性胆甾化壳聚糖两亲材料的合成及其自聚集现象

以邻苯二甲酰化壳聚糖(PHCS)为中间体,将胆甾醇琥珀酸酯(CHS)选择性接枝到壳聚糖的6-OH上,再经水合肼脱去N-邻苯二甲酰亚胺基,游离出氨基,获得疏水改性的O-胆甾醇基壳聚糖(O-CHCS)。采用傅立叶红外光谱仪(FT-IR)和核磁共振仪(1HNMR)对产物进行结构表征;通过透析法制备O-CHCS自聚集纳米粒,用透射电镜(TEM)和动态激光粒度分析仪(DLLS)表征了纳米粒的形态、粒径、粒径分布及表面电位;以芘为荧光探针测定O-CHCS的临界胶束浓度(CMC)。结果表明,合成的O-CHCS是一种两亲性化合物,能在水中自聚集形成粒径约337nm,ζ电位为+25.6mV的球形纳米粒,获得的纳米粒具有明显的核壳结构和较低的临界胶束浓度,有望成为疏水性药物或DNA的载体

Characterization of diguanylate cyclase metabolism-related gene in Azorhizobium caulinodans ORS571

[Objective] To study the phenotypes of Azorhizobium caulinodansORS571 mutant strain lacking the diguanylate cyclase AZC-2412, and to explore its functional mechanism. [Methods] We constructed the gene knockout system of rhizobia based on the homologous recombination of cre-loxp, and the mutant strain was constructed by the triparental conjugation. Growth rate, chemotactic ability, exopolysaccharide production, biofilm formation and other phenotypes of the wild type and mutant strains were studied. [Results] The mutant strain had almost the same growth rate as the wild type. Compared with the wild type, the mutant strain impaired in exopolysaccharide production, chemotaxis behavior and biofilm formation due to lower levels of c-di-GMP in cells. [Conclusion] The deletion of the diguanylate cyclase AZC-2412 reduces level of c-di-GMP levels. It had a regulatory effect on the exopolysaccharide production, bacterial motility, biofilm formation, cell flocculation of Azorhizobium caulinodans ORS571 and its interaction with host plant.</p

一种全铝发动机缸体内壁陶瓷化夹具

本发明提供了一种全铝发动机缸体内壁陶瓷化夹具，包括反应部和进液部，反应部包括阴极柱，和将阴极柱固定在缸体缸盖一端的阴极固定盖；在阴极柱位于缸体外的一端开有沿轴向延伸的排液洞，在极柱伸入缸体内的柱身上开有与排液洞连通的进液孔；进液部，包括安装在缸体曲柄一端的进液柱，和将进液柱固定在缸体曲柄一端的进液固定盖，进液柱与缸体内部形成密封接触，在进液柱的轴向上设置有贯穿通道。本发明采用发动机整机定位，缸体内由阴极柱定位反应范围，使得反应液局部接触发动机(仅仅接触缸体内壁)，实现缸体内壁完全陶瓷化。通过由下至上的排液方式可及时排出反应后的液体，同时带走缸体内的热量，使缸体内的反应温度维持在室温

小麦品种中梁88375抗条锈病基因的分子作图

【目的】中梁88375是甘肃省天水市农业科学研究所以中4/S394//咸农4号复合杂交选育而成的冬小 麦品系，对小麦三锈免疫。明确其抗条锈病基因及遗传特点，建立与其连锁的微卫星标记，以利于抗源筛选和培 育持久抗病新品种。【方法】将中梁88375与感病品种铭贤169杂交、自交和测交并对双亲及其杂交后代进行苗 期抗性鉴定。用小麦条锈菌条中31号对其进行遗传分析；采用SSR技术，选用普通小麦的320对微卫星引物对中 梁88375及铭贤169的基因组DNA进行PCR扩增和电泳分析。【结果】中梁88375对多个条锈菌小种具有良好的 抗病性,对CY31的抗病性由1对显性核基因控制，把该基因暂命名为 Yr88375。建立了与 Yr88375 连锁的6个微 卫星标记Xgwm335、 Xwmc289、 Xwmc810、 Xgdm116、 Xbarc59与 Xwmc783， 并将Yr88375定位于小麦5BL。 距离 Yr88375 最近的两个微卫星位点是Xgdm116、Xwmc810，遗传距离分别是3.1 cM和3.9 cM，最远的标记Xwmc783 与Yr88375 之间的遗传距离为13.5 cM。 【结论】系谱分析结合分子标记结果表明，Yr88375 很有可能是一个来自中间偃麦草 (E.intermedium)并与已知抗条锈病基因不同的新基因

HIRFL注入器高频腔体与高频机的匹配

叙述了兰州重离子加速器注入器(SFC)高频系统的200kW高频机与高频腔体的功率匹配,匹 配测量系统的工作原理,以及对匹配系统的改进和完善,并对高频腔体的输入阻抗和耦合电容进行了计算。为 提高高频系统的稳定性和可靠性,对影响高频功率传输和D电压提高的问题进行了深入的研究和改进。采用 矢量阻抗仪冷态测量腔体匹配阻抗的方法和一些相应的技术和措施,用矢量电压表动态测量功率输出级的相 位差,判断D电路是否工作在匹配状态,从而使SFC的D电压由原来的50～65kV(不稳定)提高到稳定工作 的105kV,改善了SFC的工作状态和保证了SFC的高效运行

A Review on Development of Dry Desulfurization Materials for DeSO_x Filter in Diesel Exhaust

NOx removal catalysts in the diesel engine exhaust system are sulfur-sensitive. The DeSOx filter upstream of NOx removal system can capture SOx to prevent NOx removal catalysts from SOx poisoning in diesel engine exhaust. This paper is oriented toward so

Preparation and Characterization of RGD-HA/PLLA Porous Composite

作者简介：杨春莉(1973-),女,黑龙江佳木斯人，讲师，博士。[中文文摘]通过碳二亚胺法将精氨酸-甘氨酸-天冬氨酸(RGD)接枝到羟基磷灰石(HA)颗粒表面,增强HA颗粒识别细胞的功能,然后将其均匀地分布于左旋聚乳酸(PLLA)中制备多孔复合材料,分别用XPS和SEM等对HA颗粒和多孔复合材料进行了表征。结果表明:RGD成功地接枝到了HA颗粒表面,多孔复合材料中RGD功能化的HA颗粒是纳米尺寸的,且分布均匀;RGD功能化HA/PLLA多孔复合材料的细胞粘附率从普通HA/PLLA多孔复合材料的37.21%提高到了69.11%。[英文文摘]RGD was grafted on HA particle surface by carbodiimide method to increase the cell recognizing function of HA particles,and then the particles were homogenously distributed in PLLA to prepare porous composite.HA particles and porous composite were characterized by XPS and SEM.The results show that RGD was successfully grafted on HA particle surface,RGD-HA particles were nano-size and homogenously distributed in the porous composite.Cell adhesive ratio of RGD-HA/PLLA porous composite increased from 37.21% of ordinary PLLA/HA to 69.11%．黑龙江省科技厅青年科学基金资助项目(Q07C308