Advanced Methodologies for Adsorption/Thermal Desorption with Tenax-TA for the Analysis of Polycyclic Aromatic Hydrocarbons and Sulfur Compounds

We have evaluated an analytical method for the determination of polycyclic aromatic hydrocarbons (PAHs) and sulfur compounds in air by means of adsorption/temperature-programmed thermal desorption (ATPTD) with small bed volume (0.08g) Tenax-TA cartridges, followed by a cryogenic trap in a precolumn with liquid nitrogen as an appropriate concentration method before capillary gas chromatography is described. The enriched components from the adsorption cartridges are transferred to the capillary column with a valveless switching system. Recoveries were determined for the complete ATPTD method. Desorption recoveries near 100% were found for various of polycyclic aromatic hydrocarbons and sulfur compounds. The sulfur compounds known to cause nuisance odors in the atmosphere near sulfur recovery and sewerage treatment works were also determined.     

Effect of Water and Ethanol Extracts from Hericium erinaceus Solid-State Fermented Wheat Product on the Protection and Repair of Brain Cells in Zebrafish Embryos

Extracts from Hericium erinaceus can cause neural cells to produce nerve growth factor (NGF) and protect against neuron death. The objective of this study was to evaluate the effects of ethanol and hot water extracts from H. erinaceus solid-state fermented wheat product on the brain cells of zebrafish embryos in both pre-dosing protection mode and post-dosing repair mode. The results showed that 1% ethanol could effectively promote zebrafish embryo brain cell death. Both 200 ppm of ethanol and water extracts from H. erinaceus solid-state fermented wheat product protected brain cells and significantly reduced the death of brain cells caused by 1% ethanol treatment in zebrafish. Moreover, the zebrafish embryos were immersed in 1% ethanol for 4 h to cause brain cell damage and were then transferred and soaked in the 200 ppm of ethanol and water extracts from H. erinaceus solid-state fermented wheat product to restore the brain cells damaged by the 1% ethanol. However, the 200 ppm extracts from the unfermented wheat medium had no protective and repairing effects. Moreover, 200 ppm of ethanol and water extracts from H. erinaceus fruiting body had less significant protective and restorative effects on the brain cells of zebrafish embryos. Both the ethanol and hot water extracts from H. erinaceus solid-state fermented wheat product could protect and repair the brain cells of zebrafish embryos damaged by 1% ethanol. Therefore, it has great potential as a raw material for neuroprotective health product.     

晶种导向下干胶法合成ZSM-5分子筛

以廉价水玻璃为硅源,在晶种替代有机模板剂的条件下采用干胶法合成了ZSM-5分子筛。利用XRD、SEM、TEM、FTIR、N₂吸附-脱附和NH₃-TPD等分析方法对合成样品进行了表征和测试,考察了合成条件对ZSM-5分子筛晶化过程的影响。结果表明,在硅铝比（n/n）为30~70,钠硅比（n/n）为0.12~0.20时都可以得到结晶度良好的ZSM-5分子筛。研究发现,干胶法合成ZSM-5,在不引入外加水的情况下也可以得到ZSM-5样品,外加水的引入能够有效地提高晶化速率;与水热法合成ZSM-5分子筛相比,干胶法可以显著地缩短晶化时间,同时,合成样品的晶体尺寸也有所减小。     

晶种导向下干胶法合成ZSM-5分子筛

以廉价水玻璃为硅源,在晶种替代有机模板剂的条件下采用干胶法合成了ZSM-5分子筛。利用XRD、SEM、TEM、FTIR、N_2吸附-脱附和NH_3-TPD等分析方法对合成样品进行了表征和测试,考察了合成条件对ZSM-5分子筛晶化过程的影响。结果表明,在硅铝比(n/n)为30~70,钠硅比(n/n)为0.12~0.20时都可以得到结晶度良好的ZSM-5分子筛。研究发现,干胶法合成ZSM-5,在不引入外加水的情况下也可以得到ZSM-5样品,外加水的引入能够有效地提高晶化速率;与水热法合成ZSM-5分子筛相比,干胶法可以显著地缩短晶化时间,同时,合成样品的晶体尺寸也有所减小。     

Symbolic-computation construction of transformations for a more generalized nonlinear Schrödinger equation with applications in inhomogeneous plasmas,optical fibers,viscous fluids and Bose-Einstein condensates

Currently, the variable-coefficient nonlinear Schr?dinger (NLS)-typed models have attracted considerable attention in such fields as plasma physics, nonlinear optics, arterial mechanics and Bose-Einstein condensates. Motivated by the recent work of Tian et al. [Eur. Phys. J. B 47, 329 (2005)], this paper is devoted to finding all the cases for a more generalized NLS equation with time- and space-dependent coefficients to be mapped onto the standard one. With the computerized symbolic computation, three transformations and relevant constraint conditions on the coefficient functions are obtained, which turn out to be more general than those previously published in the literature. Via these transformations, the Lax pairs are also derived under the corresponding conditions. For physical applications, our transformations provide the feasibility for more currently-important inhomogeneous NLS models to be transformed into the homogeneous one. Applications of those transformations to several example models are illustrated and some soliton-like solutions are also graphically discussed.     

V2O5负载量对V2O5/Al2O3氧化活化正庚烷催化裂解反应的影响

采用X射线衍射, 低温氮气吸脱附, 氨气程序升温脱附和吡啶吸附红外光谱分析方法对不同活性组分负载量V2O5/Al2O3的性质进行了表征. 根据表面VOx单元密度, 推测V2O5负载量为20%-25% (w)对应着V2O5/Al2O3表面达单层覆盖状态; V2O5的负载使Al2O3表面Lewis酸量减少, 并出现Br?nsted酸, 对应着氧化态VOx单元中的V―OH; 随着负载量的增加, Brφnsted酸量增加至负载量为20%时达到最大值. 对V2O5/Al2O3中活性组分负载量对其氧化活化正庚烷催化裂解反应的影响进行了考察. 结果表明, 在V2O5负载量为20%-25%时,V2O5/Al2O3的引入对正庚烷在HZSM-5平衡剂上催化裂解反应的促进作用最明显, 此时VOx单元在V2O5/Al2O3表面形成单层覆盖状态, 可提供最大量的表面晶格氧, 因而对正庚烷具有最强的氧化活化作用; V2O5负载量继续增加形成体相的V2O5和AlVO4, 不利于晶格氧参与正庚烷的转化, 因而反应性能有所下降.     

缺Sr的Bi-2201相材料的微结构研究

对名义组份为Bi_2Sr_(2-x)□_xCuO_y(x=0.1,0.2,0.3,0.4,0.5,0.6,0.7,其中□为空位)的系列样品的微结构进行了研究。电子衍射的研究表明,缺Sr的Bi-2201相的调制波长随着x值的增加而明显减小。Raman散射结果则显示随着调制波长缩短,晶体的结构畸变加剧,晶格无序度增加。利用调制的晶格失配模型讨论了这种由缺Sr所造成的结构畸变行为,并由此指出在Bi系氧化物中非公度调制与晶格的有序度很可能是相关的,调制波长缩短,晶格无序度增加;反之则减小。 关键词：     

Wronskian and Grammian Determinant Solutions for a Variable-Coefficient Kadomtsev-Petviashvili Equation

In this paper, we derive the bilinear form for a variable-coefficient Kadomtsev Petviashvili-typed equation. Based on the bilinear form, we obtain the Wronskian determinant solution, which is proved to be indeed an exact solution of this equation through the Wronskian technique. In addition, we testify that this equation can be reduced to a Jacobi identity by considering its solution as a Grammian determinant by means of Pfaffian derivative formulae.     

温敏核不育系水稻株1S及其矮秆突变体SV14茎的蛋白质组学比较

采用双向凝胶电泳对温敏核不育水稻株1S和其矮秆突变体SV14的茎(穗颈下第1节和第2节)蛋白进行了分离, 通过银染显色, 获得了分辨率和重复性较好的双向电泳图谱. 选取了26个蛋白质点采用MALDI-TOF-MS进行肽质谱指纹图分析, 最终有12个蛋白质点得到了可靠鉴定. 其中在SV14中相对于株1S上调的仅有OSJNBa0039C07.13 蛋白, 其它蛋白均表现为下调. 这些差异蛋白按照功能可分为4类: (1) 能量代谢相关蛋白; (2) 次生代谢相关蛋白; (3) 调控蛋白; (4) 未知蛋白. 对光合系统Ⅱ氧延伸复合物蛋白质前体2, 果糖二磷酸醛缩酶, UDP-葡糖醛酸脱羧酶对应的基因进行了半定量RT-PCR分析, 发现这几个基因与蛋白质的表达不一致, 可能是RNA发生了翻译后修饰而减少了蛋白表达量的结果. 这些差异蛋白很可能与水稻矮化有关, 为水稻矮秆基因的寻找提供了另一个有效途径.     

基于聚乙烯醇/Fe2O3纳米颗粒的纤维素酶固定化

以聚乙烯醇/Fe2O3磁性纳米颗粒为纤维素酶固定化载体, 通过反复冻融的方法成功地实现了纤维素酶固定化. 采用透射电镜、红外光谱仪、振动样品磁强度计对固定化酶复合体进行了表征, 结果显示, 固定化酶复合体为大小约1 μm的微凝胶团, 内含10 nm左右的Fe2O3纳米颗粒. 研究影响固定化因素后发现, 当pH为6, 固定化时间为11 h, 纤维素酶/PVA质量比为4, PVA/Fe质量比为50时, 固定化纤维素酶效果最好. 通过该方法固定后酶活回收率达42%, 酶水解效率显著提高, 经过5次反应后的固定化酶相对酶活力保留50%以上. 因此, 基于聚乙烯醇/Fe2O3纳米颗粒的纤维素酶固定有利于酶的循环使用并显著提高酶的使用效率, 是一种有效固定化纤维素酶的新方法.