Chemical Detection Of Selected Hallucinogens In Water

Abstract

A specific and non-destructive test for basic esters of benzilic and α-glycolic acids in water is described. The compounds are collected on a glass fiber filter as water insoluble complexes with sodium tetraphenylboron. The filter is dried and sprayed with a 2-diphenylacetyl-l, 3-indandione-l-imine derivative. A positive test is the visual observation of fluorescence.     

取代基效应(SCS)与乙烯-α-烯烃共聚物的序列结构Ⅲ.定量分析

本文在分析乙烯-α-烯烃共聚物序列结构时,把代表共单体反接单元的亚甲基(CH₂)βγ和γδ分别归属给了二元组VV和三元组EEV。与此同时,CH₂-δδ和δδ⁺归属给了二元组EE。表征乙烯长序列的CH₂-δ⁺δ⁺分属二元组EE和三元组EEE,对应峰强度在EE和EEE之间的分配是处理序列分布的关键。在本文中运用序列结构的Bovey关系和Randall统计进行演算,求得了修正值△的数学表达式,严格解和近似解。在规则链条件下得到的近似解与G.J.Ray的结果完全相同。当共单体含量较少时,谱峰强度Iδ⁺δ⁺的分配接近相等。在二元组和三元组的水平上,乙烯-α-稀烃共聚物的¹³C NMR谱中共有十三个峰,属于CH₂的有十个,属于CH的有三个。利用这些谱峰的强度数据可以建立一套计算公式,由此提供共聚物序列结构的全部信息。因此这是一个研究乙烯-α-烯烃共聚物序列结构的普适方法。     

Adsorbate motions induced by vibrational mode coupling

Adsorbate motions are discussed with a primary attention focused on the coupling between a vibrational mode excited by ultrafast laser heated hot-electrons or by inelastic tunneling electrons with scanning tunneling microscope and the reaction coordinate (RC) mode. Recent experimental results have demonstrated an efficient reaction pathways involving an indirect excitation of a frustrated translational mode, rather than its direct excitation for adsorbate hopping on surfaces. Elementary processes are briefly described for hopping of CO molecules on a laser heated stepped Pt surface, where excitation of the frustrated rotation mode has been found to plays an indispensable. Calculation of the inelastic tunneling current (ITC) for excitation of the C-O stretch mode of a CO molecule is combined with a theory of anharmonic mode coupling to activate the frustrated translation mode above the barrier. The hopping rate as a function of the bias voltage agrees with the experimental result. An unified theory of single-, and two-electron processes for ITC-induced motions induced by an indirect excitation of the RC-mode via mode coupling is also applied to reproduce a crossover from hopping to desorption of a single NH₃ molecule on Cu(1 0 0) with an increase in the tunneling current.     

Unfolding Features of Bovine Testicular Hyaluronidase Studied by Fluorescence Spectroscopy and Fourier Transformed Infrared Spectroscopy

Chemical unfolding of bovine testicular hyaluronidase (HAase) has been studied by fluorescence spectroscopy and Fourier transformed infrared spectroscopy (FTIR). Thermodynamic parameters were determined for unfolding HAase from changes in the intrinsic fluorescence emission intensity and the formations of several possible unfolding intermediates have been identified. This was further confirmed by representation of fluorescence data in terms of ‘phase diagram’. The secondary structures of HAase have been assigned and semiquantitatively estimated from the FTIR. The occurrence of conformational change during chemical unfolding as judged by fluorescence and FTIR spectroscopy indicated that the unfolding of HAase may not follow the typical two-state model.     

用有限解析差分格式数值求解化学输运方程

本文用有限解析差分格式研究在多孔介质中化学输运问题的数值模型,系统地计算结果表明:1.有限解析差分格式能够消除数值弥散和伪振荡; 2.随着弥散数(Peclct数)的减小(增加),浓度突破曲线将延迟到达和形状变陡,最终趋近浓度对流曲线;3.当流速数增加后,非稳态吸附对浓度分布的影响趋近稳态吸附的影响。     

药物小分子化学位移的量子化学计算研究

核磁共振的谱峰归属对分子结构的确定至关重要,用理论计算方法预测化学位移对谱峰的正确归属是极其有帮助的. 我们用量子化学的方法预测了乙酰水杨酸及其衍生物分子上碳原子的化学位移,并通过比较计算值和实验值得到不同理论计算方法的误差范围. 用HF和DFT理论计算芳环碳的化学位移时,CSGT方法比GIAO方法更为准确. 与其它方法相比,B3PW91//CSGT 在6-311G(d,p)基组下得到的芳环碳的化学位移最接近实验值. 采用B3LYP//GIAO计算时, 使用不同的基组 6-31G(d,p)和6-311++G(3df,3pd)得到的化学位移计算值只有δ 0.01~2.04的差异. MP2方法非常耗时,且对于计算精度的改善并不显著; 并且,由于电子相关性的影响,碳原子周围的电子环境对化学位移计算的准确性影响很大. 与实验值比较,HF方法由于忽略电子相关效应所以表现较差. 另外,碳链的增长对计算准确性也存在一定影响.      

羧酸甲乙酯中羰基17O-NMR化学位移研究

提出了计算羧酸甲乙酯中羰基¹⁷O-NMR化学位移的公式：δ_cal（¹⁷O）=360.0+Δα+Δβ+Δγ,通过线性回归法确定了22种取代基参数.经回归检验表明该公式计算结果置信度为99.5%,与实验值的偏差Δδ在5.0以内的羰基¹⁷O-NMR化学位移计算值~100%.     

六聚吡咯/丝组缀合物结构的NMR和 ESI-MS/MS表征

利用片断合成法合成了具有DNA切割能力的六聚吡咯/丝组缀合物, 检测了该化合物的¹H、¹³C NMR 和ESI-MS/ MS 图谱, 确证了该化合物的结构, 通过¹H-¹H COSY, HSQC,HMBC等2D NMR 技术对其¹H 和¹³C NMR 数据进行了归属和解析, 并探讨了其ESI-MS/ MS 质谱裂解规律.     

气相爆轰波在分叉管中传播现象的数值研究

数值研究气相爆轰波在分叉管中的传播现象.用二阶附加半隐龙格-库塔法和5阶WENO格式求解二维欧拉方程,用基元反应描述爆轰化学反应过程,得到了密度、压力、温度、典型组元质量分数场及数值胞格结构和爆轰波平均速度.结果表明:气相爆轰波在分叉管中传播,分叉口左尖点的稀疏波导致诱导激波后压力、温度急剧下降,诱导激波和化学反应区分离,爆轰波衰减为爆燃波(即爆轰熄灭).分离后的诱导激波在垂直支管右壁面反射,并导致二次起爆.畸变的诱导激波在水平和垂直支管中均发生马赫反射.分叉口上游均匀胞格区和分叉口附近大胞格区的边界不是直线,其起点通常位于分叉口左尖点上游或恰在左尖点.水平支管中马赫反射三波点迹线始于右尖点下游.分叉口左尖点附近的流场中出现了复杂的旋涡结构、未反应区及激波与旋涡作用.旋涡加速了未反应区的化学反应速率.反射激波与旋涡作用并使旋涡破碎.反射激波与未反应区作用,加速其反应消耗,并形成一个内嵌的射流.数值计算得到的波系演变和胞格结构与实验定性一致.