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991.
Dr. Hui Cai Zhan‐Yi Sun Zhi‐Hua Huang Lei Shi Prof. Dr. Yu‐Fen Zhao Prof. Dr. Horst Kunz Prof. Dr. Yan‐Mei Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(6):1962-1970
Glycopeptides of tumor‐associated mucin MUC1 are promising target structures for the development of antitumor vaccines. Because these endogenous structures were weakly immunogenic, they were coupled to immune‐response‐stimulating T‐cell epitopes and the Pam3Cys lipopeptide to induce strong immune responses in mice. A new thioether‐ligation method for the synthesis of two‐ and three‐component vaccines that contain MUC1 glycopeptides as the B‐cell epitopes, a T‐cell epitope peptide, and the Pam3CSK4 lipopeptide is described. The resulting fully synthetic vaccines were used for the vaccination of mice, either in a liposome with Freund′s adjuvant or in aqueous PBS buffer. The three‐component vaccines that contained the Tetanus Toxoid P2 T‐cell epitope peptide induced strong immune responses, even when administered just in PBS. By activation of the complement‐dependent cytotoxicity (CDC) complex, the antisera induced the killing of tumor cells. 相似文献
992.
Dr. Dongpeng Yan Dr. Dejan‐Krešimir Bučar Dr. Amit Delori Bhavnita Patel Dr. Gareth O. Lloyd Prof. William Jones Prof. Xue Duan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(25):8213-8219
Multi‐component organic nanocrystals that are comprised of two or more supramolecular building blocks can be used to extend the design and assembly scope of solid molecular materials. Herein, we report the use of ultrasonication to prepare halogen‐bonded stilbene‐based nano‐cocrystals that exhibit different photoemission properties, including one‐ and two‐phonon emission and fluorescence lifetimes, relative to those of macrodimensional crystals. The structural transformation from nano‐cocrystals into nanocrystals upon heating results in a luminescence red‐shift from greenish blue to yellow. The temperature‐dependent ratiometric luminescence may allow such nano‐cocrystals to be used as fluorescent sensors and thermosensitive materials. 相似文献
993.
Feng Zou Prof. Xianluo Hu Dr. Yongming Sun Dr. Wei Luo Fangfang Xia Long Qie Yan Jiang Prof. Yunhui Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(19):6027-6033
Zn2GeO4/N‐doped graphene nanocomposites have been synthesized through a fast microwave‐assisted route on a large scale. The resulting nanohybrids are comprised of Zn2GeO4 nanorods that are well‐embedded in N‐doped graphene sheets by in situ reducing and doping. Importantly, the N‐doped graphene sheets serve as elastic networks to disperse and electrically wire together the Zn2GeO4 nanorods, thereby effectively relieving the volume‐expansion/contraction and aggregation of the nanoparticles during charge and discharge processes. We demonstrate that an electrode that is made of the as‐formed Zn2GeO4/N‐doped graphene nanocomposite exhibits high capacity (1463 mAh g?1 at a current density of 100 mA g?1), good cyclability, and excellent rate capability (531 mAh g?1 at a current density of 3200 mA g?1). Its superior lithium‐storage performance could be related to a synergistic effect of the unique nanostructured hybrid, in which the Zn2GeO4 nanorods are well‐stabilized by the high electronic conduction and flexibility of N‐doped graphene sheets. This work offers an effective strategy for the fabrication of functionalized ternary‐oxide‐based composites as high‐performance electrode materials that involve structural conversion and transformation. 相似文献
994.
995.
Ross S. Winter Dr. Jun Yan Dr. Christoph Busche Dr. Jennifer S. Mathieson Dr. Alessandro Prescimone Prof. Euan K. Brechin Dr. De‐Liang Long Prof. Leroy Cronin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):2976-2981
Two near isomeric clusters containing a novel {Mn8W4} Keggin cluster within a [W36Mn10Si4O136(OH)4(H2O)8]24? cluster are reported: K10Li14 [W36Si4O136MnII10(OH)4(H2O)8] ( 1 ) and K10Li13.5Mn0.25[W36Si4O136MnII10(OH)4(H2O)8] ( 1′ ). Bulk characterization of the clusters has been carried out by single crystal X‐ray structure analysis, ICP‐MS, TGA, ESI‐MS, CV and SQUID‐magnetometer analysis. X‐ray analysis revealed that 1′ has eight positions within the central Keggin core that were disordered W/Mn whereas 1 contained no such disorder. This subtle difference is due to a differences is how the two clusters assemble and recrystallize from the same mother liquor and represents a new type of isomerism. The rapid recrystallization process was captured via digital microscopy and this uncovered two “intermediate” types of crystal which formed temporarily and provided nucleation sites for the final clusters to assemble. The intermediates were investigated by single crystal X‐ray analysis and revealed to be novel clusters K4Li22[W36Si4Mn7O136(H2O)8]?56 H2O ( 2 ) and Mn2K8Li14[W36Si4Mn7O136(H2O)8]?45 H2O ( 3 ). The intermediate clusters contained different yet related building blocks to the final clusters which allowed for the postulation of a mechanism of assembly. This demonstrates a rare example where the use X‐ray crystallography directly facilitated understanding the means by which a POM assembled. 相似文献
996.
Hyperbranched polymer HSDA was synthesized from methyl acrylate, tetraethylenepentamine, and dodecanoic acid by melt polycondensation. ZnO nanoparticle colloidal solution was prepared in one step by mixing Zn(NO3)2 and HSDA aqueous solution under hydrothermal condition. The results of transmission electron microscopy and ultraviolet–visible (UV–Vis) spectroscopy indicated that ZnO nanoparticles were formed in colloidal solution. Bamboo pulp fabric was treated with ZnO nanoparticle colloidal solution by an impregnation method to provide the bamboo pulp fabric with antibacterial and UV protective properties. The whiteness, antibacterial activity, UV protective property, and washing durability of the ZnO nanoparticle-treated fabrics were determined. The results indicated that the bamboo pulp fabric treated with ZnO nanoparticles showed good UV protective properties and its ultraviolet protection factor (UPF) can reach 90.38. The UPF value of treated fabric drops to 70.42 after washing for 20 times, but it retains good UV protective properties. The ZnO nanoparticle-treated fabric showed 99.91 % bacterial reduction of Staphylococcus aureus and 99.97 % bacterial reduction of Escherichia coli. The fabric retained over 98.93 % reduction level even after being exposed to 20 consecutive home-laundering conditions. In addition, the results of scanning electron microscopy and X-ray spectroscopy confirmed that ZnO nanoparticles were fixed and well dispersed on bamboo pulp fabric. 相似文献
997.
利用氢氧化钾对苯乙烯-马来酸酐交替共聚物(SMA)进行水解,所得中等皂化程度的SMA水解产物(SMAA)在水溶液中具有刚性棒状直链构型;将此特殊结构的大分子作为分散剂用于苯乙烯悬浮聚合,通过控制搅拌速度和油水比,可得到梭形聚苯乙烯粒子;在优化条件下,粒子平均长度6.8 mm,宽度1.4 mm,厚度0.5 mm,长径比约5.0.其可能的机理为,中等皂化程度的刚棒直链型SMAA在聚合物"软粒子"表面能形成难以"回复"的有效保护层,使由剪切形成的变形聚合物"软粒子"在聚合过程中能保持形状和尺寸的稳定,从而得到梭形聚合物粒子. 相似文献
998.
应用密度泛函理论PBE0 方法研究具有分子导线潜在应用的金属串配合物M3(dpa)4Cl2 (1: M=Co, 2: M=Rh, 3: M=Ir; dpa=dipyridylamide)在电场作用下的几何和电子结构. 结果表明: 配合物基态均是二重态. 1和2的M36+金属链形成三中心三电子σ键, 3 中M36+形成三中心四电子σ键且存在弱的δ键. 随金属原子周期数增大其M―M键增强、LUMO与HOMO能隙减小、金属原子的反铁磁耦合减弱以至消失且自旋密度向配体的离域增强. 在Cl4→Cl5 电场作用下, 低电势端的M3-Cl5 键缩短, 高电势端的M2―Cl4 键增长, M―M平均键长略为缩短, M―M键增强, 有利于分子线的电子传递; 分子能量降低, 偶极矩线性增大. 低电势端Cl5的负电荷向高电势端Cl4 转移, 且3 中金属原子的正电荷由高电势端向低电势端的转移较明显, 自旋电子由低电势端向高电势端金属原子移动, 但桥联配体dpa-与M和Cl 所在的分子轴间没有电荷转移. 电场使LUMO与HOMO能隙减小, 有利于分子的电子输运. 随金属原子周期数增大, 电场作用下M―M平均键长变化减小, LUMO、HOMO的能级交错现象减少. 相似文献
999.
采用分光光度法测定婴幼儿食品中硫氰酸钠的含量。详细叙述了不同样品的溶样方法,超声溶解时间及蛋白质沉淀剂的选择等。样品溶液中的SCN-与Fe3+生成血红色的络合物,其最大吸收波长位于457nm处。硫氰酸钠的质量浓度在20mg·L-1以内与其吸光度呈线性关系,方法的检出限为1.670g·kg-1。方法用于婴幼儿食品中硫氰酸钠的测定,加标回收率在91.8%~98.7%之间。 相似文献
1000.
采用水热合成法制备了一个一维配位聚合物{[Co(dpa)(H2O)4].(dpdo).(H2O)}n(1)(H2dpa=2,2′-联苯二酸,dpdo=N,N′-二氧化-4,4′-联吡啶),通过红外光谱、紫外光谱、元素分析、XRPD、TGA和X-射线单晶衍射进行了表征。Co(Ⅱ)原子采取了畸变的八面体构型,6个配位氧原子分别来自于2个dpa2-配体和4个配位水分子。每一个dpa2-配体桥联2个Co髤中心,每一个Co(Ⅱ)原子与2个dpa2-配体配位进而形成了21螺旋链结构。借助溶剂水分子的连接作用,螺旋链之间通过多种O-H…O氢键作用形成了2D网格,通过dpdo和2D网格之间多种类型的氢键作用形成了三维超分子结构。测定了室温下聚合物1的固体荧光光谱。 相似文献