吲哚-3-丁酸无保护流体室温燐光和胶束增稳室温燐光性质的比较

仔细研究了吲哚-3-丁酸(IBA)的无保护流体室温燐光(NP-RTP)及以高分子分散剂聚乙二醇-200,聚乙二醇-400和非离子表面活性剂Tween-20,Tween-40, Tween-80,Tween-85,Brij35和乳化剂OP为介质的流体室温燐光性质。表面活性剂和高分子分散剂能抑制IBA燐光猝灭,使其具有更低的检出限,同时也使燐光强度-激发光照射时间曲线发生改变,但不影响IBA燐光光谱特性。无论是否存在表面活性剂或高分子分散剂,TlNO₃都不能诱导IBA产生燐光,KI却能诱导其产生强烈燐光。用于强化水样和土壤样品中IBA的测定,回收率95.2%～104%,相对标准偏差2.4%～4.0%。     

异金属Cu-Ag有机配位聚合物的光物理性质

通过分子组装的方法,在相同的反应条件下,调节控制反应物铜银前驱体的反应配比,设计合成了1,8—二异氰—萜烷(L)的异金属铜银配位聚合物{[CuxAg1-x(L)2][BF4]}n(x=1．0,0．95,0．78,0．52,0．19,0．05,0),详细研究了配合物的光物理性质。发现紫外吸收光谱和荧光发射光谱随着不同金属配比的配位聚合物分子链长的改变,最大吸收和发射位置呈现谱带移动。     

苯甲酸脱羧反应过程的拉曼光谱研究

应用水热金刚石压腔结合拉曼光谱技术研究了升温过程中苯甲酸在水中的变化及拉曼谱图。结果表明：低温升温过程中,苯甲酸的拉曼谱图中各个特征振动谱峰没有变化,苯甲酸没有与水反应。随着温度的继续升高,苯甲酸的拉曼谱图中的特征振动峰逐渐变弱。升至150 ℃时,羧基的拉曼特征谱峰消失,说明此过程中苯甲酸发生了脱羧反应。继续升温至170 ℃,苯甲酸溶解消失。随后将体系降至常温,发现有晶体析出。由其拉曼谱图可知,重结晶的晶体含有苯环的特征峰,说明有芳香烃析出。但是没有测到羧基的特征拉曼谱峰,说明重结晶的晶体不是苯甲酸。整个过程可以说明,芳香烃在溶解重结晶过程中是可逆的,羧基是不可逆的。     

磷光寿命法研究无保护流体室温磷光的重原子效应和发光动力学参数

以两种卤代萘为模型化合物，基于磷光寿命的定义τ＝τ^-，τ0＝1／kp和其与各速率常数的关系，导出了一种类似于Stern-Volmer方程的线性方程：τ0／τ＝（kp_kic)/kp=1 kic/kp=1 Ksv.c。通过测定不同重原子微扰剂浓度时的磷光寿命，探讨了从两种途径计算流体室温磷光发射相关动力学参数的可行性和方法，通过这些参数对比讨论了KI和TINO3两种重原子微扰剂对这两种卤代萘无保护流体室温磷光发射的重原子效应的差异。     

木质纤维素生物质催化转化制备苯甲酸

In the present work, we reported a novel route for the conversion of lignocellulosic biomass (sawdust) to a high-value chemical of benzoic acid under atmospheric pressure. The trans- formation involved the catalytic pyrolysis of sawdust into aromatics, the decomposition of heavier alkylaromatics to toluene, and the liquid-phase oxidation of toluene-rich aromatics to benzoic acid. The production of the desired benzoic acid from the sawdust-derived aro- matics, with the benzoic acid selectivity of 85.1 C-mol% and nearly complete conversion of toluene, was achieved using the MnO₂/NHPI catalyst at 100 ℃ for 5 h. The in uence of adding methanol on the catalytic conversion of sawdust to the core intermediate of toluene was also investigated in detail.     

Preparation and Properties of Polylactic Acid (PLA)/Silica Nanocomposites

Surface-modified silica was incorporated into bio-based polylactic acid (PLA) to improve its performance. The modification by aminosilane on the silica was confirmed through FTIR (Fourier transform infrared) spectra. Following the aminosilane modification, polyethylene glycol methyl ether (PEGME) was grafted, via the aminosilane, on the silica to form the desired surface-modified silica (PEGME-silica). The grafting percentage of polyethylene glycol methyl ether was about 6.9 wt%. Unmodified silica, having underwent a similar treatment to maintain the same thermal history but without adding silane and PEGME, was also prepared. The PEGME-silica system had slightly higher tensile strength than the unmodified silica system, with a rheological study showing an enhanced polymer matrix-dispersed silica interaction and better dispersion in morphology observations being proposed as the cause. The dynamic storage modulus in the terminal zone was reduced for large amounts of highly dispersed surface-modified silica in comparison with unmodified silica. Tan δ decreased significantly with increasing unmodified silica contents in the low frequency region, resulting in solid-like behaviors. On the other hand, there was only a limited decrement for modified silica-filled samples in the corresponding ranges, especially for low dosages of the modified silica. The shear thinning phenomenon appeared to be more pronounced for unmodified silica at high silica content, but not for modified silica. To the best of our knowledge, this is the first report of the effect of polyethylene glycol methyl ether (PEGME)-modified nanosilica on the properties of PLA/silica nanocomposites prepared under a melt mixing process to illustrate the significance of surface modification via Cole–Cole plots.     

基于LS-SVM和THz光谱技术的面粉中苯甲酸检测研究

面粉（小麦粉）是中国北方大部分地区的主食,苯甲酸是重要的酸型食品防腐剂,为了便于食品长期保存,往往会添加苯甲酸以便延长食品保存时间。但食用添加苯甲酸过量的小麦粉会对身体健康产生严重危害。太赫兹技术是一种新兴的检测技术,由于处于特殊的0.1～10 THz的太赫兹频段,在食品安全检测方面体现出了很强的应用潜力。主要致力于探索太赫兹光谱技术检测苯甲酸的合理性、可行性,利用太赫兹时域光谱技术对面粉中的食品添加剂苯甲酸进行实验研究。实验获取了面粉和苯甲酸的太赫兹时域光谱和频域光谱,其吸收系数显示苯甲酸的特征吸收峰在1.94 THz波段,面粉的太赫兹吸收系数几乎以一定的斜率增加,说明可以用THz-TDS（Terahertz time domain spectrum）技术对面粉中的苯甲酸进行特征识别。为建立面粉中添加剂苯甲酸的定量检测模型,实验获取了面粉中掺杂不同百分比（质量分数）苯甲酸的太赫兹时域光谱,计算得到吸收系数谱。实验发现吸收峰幅度的变化是与苯甲酸的含量成正比的,苯甲酸含量增加吸收峰幅度变大。首先探索了不同光谱预处理方法对太赫兹光谱的影响,采用如平滑校正、多元散射校正、基线校正和归一化等方法对原始光谱进行校正处理。校正之后,建立相应的PLS (partial least squares)模型以选择最优预处理方法。然后分别建立苯甲酸浓度和太赫兹吸收系数的MLR (multiple linear regression)、PLS和LS-SVM（partial least squares support vector machines）回归模型,并对比分析不同模型的优劣。将光谱数据归一化后建立的PLS模型更具有优势,预测相关系数R_p为0.979,预测均方根误差RMSEP为1.30%。LS-SVM与PLS和MLR模型相比,LS-SVM模型可以获得更好的建模结果,LS-SVM的预测相关系数R_p为0.987,预测均方根误差RMSEP为1.10%。利用MLR方法仅使用1.946和1.869 THz两个波段点进行建模,建模效果预测相关系数R_p为0.955,预测均方根误差RMSEP为1.90%。通过该研究为面粉中苯甲酸添加剂的无损检测提供了新的解决方案,也为其他类型的添加剂的检测提供了方法指导,对促进面粉行业的健康发展具有重要的意义。     

苯甲酸与苯甲酸钠的太赫兹光谱和振动模式分析

采用太赫兹时域光谱技术测量了苯甲酸及其钠盐苯甲酸钠在8～115 cm-1的特征吸收光谱,分析总结了苯甲酸实测特征吸收峰的归属,并利用密度泛函理论对苯甲酸钠进行了结构优化和振动模式计算。结果表明：利用苯甲酸和苯甲酸钠在太赫兹波段的特征吸收谱完全可以辨识这两种性状相似的物质;导致苯甲酸钠和苯甲酸太赫兹特征吸收谱存在差异的根本原因是苯甲酸钠的离子键影响了分子内共价键的键长和原子间的键角以及其在晶胞内分子间的相互作用和排列组成;除了苯甲酸的107 cm-1和苯甲酸钠的54 cm-1 吸收峰,苯甲酸和苯甲酸钠的其余实测特征吸收峰均来源于分子的集体振动。     

酞菁氯镓复合凝胶玻璃的谱学性能研究

采用溶胶-凝胶(Sol-Gel)湿化学工艺将酞菁氯镓(GaPcCl)掺入二氧化硅(SiO₂)凝胶玻璃基质,制备出均匀掺杂的GaPcCl复合凝胶玻璃,并对复合体系的红外光谱(IR)、紫外-可见吸收光谱(UV-Vis)及荧光光谱等谱学性能进行了测试。结果表明：GaPcCl的掺杂对凝胶玻璃基质的红外光谱没有产生显著影响;掺杂GaPcCl在复合体系中二聚体吸收峰的强度较其DMF溶液有所增大;掺杂GaPcCl在复合体系中荧光强度随浓度的增加远大于DMF溶液。     

菲并咪唑衍生物蓝光材料的合成、光物理性质及理论计算

合成了两个蓝光材料2-苯基-1H-[9,10-d]菲并咪唑(Phen-PI)和2-吡啶-1H-[9,10-d]菲并咪唑(PyriPI),光物理分析表明Phen-PI和Pyri-PI的最大发射峰分别位于371.5 nm,388.5 nm和403.5 nm,相对量子效率分别为0.383和0.528,激发态衰减寿命分别为3.87 ns和3.68 ns。通过密度泛函理论(DFT)对化合物的前线分子轨道成分和能级分布分析表明,当把Phen-PI中的苯基被吡啶环取代后,Pyri-PI的HOMO能级和LUMO能级分别下降0.09 e V和0.23 e V,同时Pyri-PI的HOMO轨道和LUMO轨道的能级差比Phen-PI减少0.14 e V,在理论层面上解释了Pyri-PI发射光谱的红移。     

纳米碳管复合凝胶玻璃结构及谱学性能研究

用物理掺杂工艺将纳米碳管引入二氧化硅凝胶玻璃基质,成功制备了纳米碳管复合凝胶玻璃,采用X射线衍射、透射电子显微镜、紫外-可见吸收光谱、红外光谱、拉曼光谱等测试方法对其结构和谱学性能进行了表征。结果表明,通过优化掺杂工艺能够实现纳米碳管与基质的均匀复合,纳米碳管本身的结构在掺杂过程中并未发生改变。纳米碳管的引入对二氧化硅凝胶玻璃基质的紫外-可见吸收光谱和红外光谱未产生显著影响。     

苯甲酸及其甲基取代物的激光光解研究

研究了苯甲酸及其甲基取代物在248 nm激光作用下的光电离及光激发行为,测定了光电离量子产额和激发三线态寿命及其自猝灭速率常数。实验结果显示甲基在苯环不同位置的取代对苯甲酸化合物激发三线态的影响不明显。利用分步双激光技术对苯甲酸激发态进行共振激发,对可能生成的瞬态产物进行了初步探讨。     

苯甲酸超声辅助电降解动力学过程的解析

基于苯甲酸超声辅助电降解过程的动力学 光谱两维数据矩阵 ,利用固定窗口尺寸渐进因子分析法确认了该降解过程中中间体的存在 ,继而根据迭代目标转化因子分析法、最小二乘回归等化学计量学方法求得了各吸光组分的表观动力学谱 ,结合组分间存在等吸收点这一光谱特征 ,求得了各吸光组分特别是难于直接测量的中间体的实际动力学谱及吸收光谱。进一步研究了苯甲酸的超声辅助电催化氧化降解过程的动力学模型。     

Determination of Trace Bismuth by a Solid Substrate Room Temperature Phosphorescence Quenching Method Based on Anionic Polymeric Acryclic Acid Lead Particles Containing Luminescent Eosine Molecules

Abstract

Luminescent particles of Anionic Polymeric Acryclic Acid Lead (Pb(PAA)₂) which containing eosine(HFInBr₄), Eosine nanomicroball of anionic polypropylene acid lead contained luminophores (short for E.N.PAA.L.C.L), were synthesized by a sol‐gel method, using anionic polymeric acryclic acid sodium (PAANa) as the precursor and Pb²⁺ as the precipitant. NH₄Ac‐HAc can react with the Pb²⁺ in E.N.PAA.L.C.L, causing it to decompose into aqueous soluble components. E.N.PAA.L.C.L‐ NH₄Ac‐HAc can emit strong and stable solid substrate room temperature phosphorescence (SS‐RTP) on filter paper, and bismuth, mercury or iodine can cause a decrease in phosphorescence intensity. Based on the facts above, a new method for the determination of trace bismuth by an SS‐RTP quenching method was established. The linear range of this method was 0.01–0.20(pg spot^?1) (4.0×10^?12 g ml^?1) of Bi³⁺, with a detection limit (LD) of 0.0016 pg spot^?1, and the regression equation of the working curve was ΔIp=61.01+237.8 m_Bi3+ (pg spot^?1), r=0.9992. This method was applied to the determination of trace bismuth in human hair and well water samples with satisfactory results. The mechanism of SS‐RTP emission was also discussed.     

Spectroscopic Study on the Photophysical Properties of Lanthanide Complexes with Long Chain Mono-Docosyl Phthalate

Ortho phthalic anhydride was modified with long chain alcohol (1-docosanol) to its corresponding monodocosyl phthalate (22-Phth). Subsequently, three novel lanthanide (Eu³⁺, Tb³⁺, and Dy³⁺) complexes with the long chain monodocosyl phthalate were synthesized and characterized by elemental analysis and Infrared spectra. The photophysical properties of these complexes were studied in detail with ultraviolet-visible absorption spectra, low temperature phosphorescence spectra and fluorescent spectra. The triplet state energy of 22-Phth was determined to be around 25,000 cm⁻¹ from the maximum phosphorescent peak at 400 nm, suggesting 22-Phth is suitable for the sensitization of the luminescence of Eu³⁺, Tb³⁺, and Dy³⁺. The fluorescence excitation and emission spectra for these lanthanide complexes of the three ligands take agreement with the above predict from energy match principle.     

异硫氰酸荧光素标记抗体的固体基质室温磷光性质研究

研究了异硫氰酸荧光素（FITC）标记的羊抗人抗体（GAHAb-FITC)和兔抗羊抗体9RAGAb-FITC)，及其以三种免疫方式与人免疫球蛋白（IgG)反应所得免疫复合物在多种固体薄膜基质上发射室温磷光（RTP）的适宜条件及其光谱，强度和寿命等性质。研究发现，标记抗体及其免疫复合物保留了FITC优良的固体基质室温磷光性质，λ m0643em^(max)=525/650nm，其RTP强度与其浓度线性相关，并有很高的灵敏度，更为重要的是，免疫反应及其RTP检测能结合于同一基质，方便地相继完成，在聚酰胺膜（PM）上，以Pb(Ac)2为重原子微扰剂，稀释比为1：10（ψ）的GAHAb-FITC,RAGAb-FITC及其与人IgG形成的免疫复合物均能发射较强制 RTP信号并有较长的RTP寿命，本结果为建立相应的固体基质室温磷光免疫分析（SS-RTP-IA）新方法奠定了相应的实验基础。     

毛细管电泳法分离测定潮汕凉果中的山梨酸、苯甲酸、糖精钠

采用毛细管电泳-PDA检测法,考察了pH、缓冲介质、波长、电压对山梨酸、苯甲酸、糖精钠分离测定的影响,得到优化的实验条件.以20mmol/乙磷酸盐(pH=7.4)为运行缓冲液,12kV为分离电压,检测通道波长为:192、202、254nm的电泳条件下,进样时间5s,山梨酸、苯甲酸、糖精钠可在15min内实现分离.山梨酸在0.250-100mg/L,苯甲酸在0.100-50.0mg/L,糖精钠在0.100-50.0mg/L范围内呈良好的线性关系,迁移时间、峰面积相对标准偏差均小于1.41%(n=5).用上述方法对实际样品进行测定,回收率在90.9%以上.     

铽与苯甲酸及其衍生物配合物的合成与发光特性

合成了铽与苯甲酸及其衍生物(苯甲酸、邻苯二甲酸、间苯二甲酸、水杨酸、邻氨基苯甲酸、磺基水杨酸)的配合物。经元素分析确定其组成结构式。研究了它们的红外吸收光谱、紫外吸收光谱及荧光光谱。紫外光谱的研究表明,配合物的紫外吸收主要表现为配体的吸收;红外光谱的研究表明,配合物的红外光谱不同于自由配体的红外光谱;荧光光谱的研究表明,铽与这六个配体的配合物都表现出较好的荧光性能,并发现磺基水杨酸铽配合物在本实验系列中其荧光发射最强。     

Isotope Effects in the Electrochemical Reduction of Oxalic Acid-D2 and Benzoic Acid-D

Abstract

The electrochemical reduction of model carboxylic acid at lead cathodes in deuterated media was studied for potential use in the synthesis of special deuterated compounds.

Oxalic acid-d₂ in D₂O gives good yields of glyoxylic acid-d₂. An unexpected large isotope effect of 5.3 ± 1.7 was found in this reaction, leading to significant depletion of deuterium content in the aldehyde group.

Benzoic acid-d in CD₃OD/diluted D₂SO₄ yields benzyl alcohol-d, 7,7-d₂. The isotope effect of 2.4 ± 1.0 is within the expected range. No deuterium is incorporated into the aromatic nucleus. Essentially unlabelled benzyl alcohol is obtained in CD₃OH/dil. H₂SO₄.     

染料掺杂的SiO2基近紫外波段固体激光材料的研究

采用溶胶－凝胶技术技术合成了掺杂近紫外波段激光染料ＢＰＢＤ－３６５的ＳｉＯ２基因体材料,用波长为３０８ｎｍ的ＸｅＣｌ激光器件泵浦源,横向泵浦获得了峰值波长为３６４ｎｍ的激光输出。在泵浦光能量为１０ｍＪ时激光输出达到０．２０ｍＪ,转换效率为２．０％。