NAD(P)H辅酶模型物结构与反应性关系的研究──3-位酰基的电子效应

合成了一系列3酰胺基氮取代的NAD(P)H模型物,测定了其与5硝基异喹啉正离子的二级反应速率常数,并与模型物的氧化还原电势进行了比较.实验结果表明,模型物3位酰基氧一方面可离域二氢吡啶环上N的电子;另一方面负电性的3位酰基氧在反应过渡态中又可引起分子内和分子间的两种静电作用;3位酰基的电子效应对模型物动力学反应性的影响是这两种效应综合作用的结果.     

渣油在加氢处理中的性质和结构变化规律研究

利用渣油加氢处理中试装置,获得了经过脱金属催化剂、脱硫催化剂和脱氮催化剂的系列渣油加氢处理产物,分析了各产物的性质。随加氢深度增加,硫、氮、残炭、镍和钒在渣油加氢产物中的的质量分数降低,总脱除率分别为84.9%、51.3%、62.8%、84.8%和94.0%。各产物的组分分布发生变化,饱和分组分增加,芳香分、胶质、沥青质组分减少,重组分胶质和沥青质组分的转化分别达到了57.5%和73.3%。以核磁共振为基础计算了渣油加氢产物组分的平均结构参数。结果表明,芳香分和胶质组分单元结构芳香环数和环烷环数减少,芳香碳分率fA、环烷碳分率fN和烷基碳分率fP变化不明显;而沥青质分子fA增加,fN和fP降低。从平均结构参数还可以看出,不同加氢产物同一种组分在结构上有其共性,但不同组分有明显区别。     

小波包分析用于重叠分析化学信号的处理

对小波包分析的算法进行了改进,并将此算法成功地应用于多组分重叠色谱信号的解析.结果表明,本文提出的算法解决了MRSD算法的不足,更适合处理分析化学信号,用于重叠信号的解析时不需重构(逆变换),简化了数据处理步骤,加快了数据解析速度,具有较强的解析能力.对于重叠色谱信号的解析,小波包分析比小波分析具有更强的解析能力.     

松香改性酚醛环氧树脂的合成与表征

以松香,环氧氯丙烷,甲醛及苯酚等为主要原料,合成了一种新型的环氧树脂。通过正交实验法确定了环氧化反应的最佳实验条件,即环氧化温度90℃,碱用量13 g,催化剂为cat 1,其最佳用量为0.018 mol,环氧氯丙烷的用量为50 g,碱浓度为30%(以上数值均以松香用量为70 g时计)。在最佳实验条件下合成得到了松香改性酚醛环氧树脂(简称RAPE),并用HPLC、FT-IR、NMR对其进行结构表征。结果表明,得到的RAPE其环氧值为0.28 mol/100g,平均聚合度约为3.4,酚羟基和树脂酸上的羧基基本反应完全,得到一种新型的缩水甘油醚型和缩水甘油酯型的环氧树脂。     

N-异丙基丙烯酰胺/丙烯酸十八酯共聚物水溶液胶束及相分离行为研究

合成了N异丙基丙烯酰胺(NIPAM)和丙烯酸十八酯(ODA)的共聚物.利用荧光探针和滴重法研究了NIPAMODA共聚物在水溶液中的胶束形成过程.同时还利用荧光探针法研究了共聚物水溶液在温度升高时出现的LCST(LowerCriticalSolutionTemperature)现象,表明该高分子在温度升高时存在着相分离现象.利用LB技术测量共聚物不溶单分子膜的PA曲线,发现随着温度升高共聚物的单分子膜越来越凝聚的反常现象,这从另一个侧面证实了共聚物NIPAMODA的相分离行为,并对此现象作了讨论.     

电感耦合等离子体原子发射光谱法测定钛合金中钨、铌、钽

采用电感耦合等离子体原子发射光谱法（ICP-AES）法测定钛合金中W,Nb,Ta元素的含量。样品采用盐酸、氢氟酸和硝酸溶解,并对仪器工作参数和试验条件进行了优化试验,确定了仪器最佳工作条件,考察了钛合金基体和共存元素对待测元素的影响,确定了各待测元素谱线为W207．911nm,Nb309．418nm,Ta240．063nm。选定的待测元素分析线不受合金基体和共存元素的干扰,通过基体匹配消除基体的影响。加标回收率在98％104％之间,测定结果的相对标准偏差为0．3％～2．4％（n=8）,方法的检出限为0．003-0．013μg／mL。进行了标准物质对照试验,试验结果与标准值相符。     

5-(2-羧基苯基)-10,15,20-三苯基卟啉对氨基酸酯的分子识别模型研究

对氨基酸及其衍生物的分子识别一直是仿生化学领域中的重要课题.以金属卟啉配合物作为主体分子对氨基酸酯的分子识别是最近几年来的热点之一^[15].氨基酸是蛋白质的主要组成部分,在蛋白质合成过程中,对氨基酸及其衍生物的识别是关健的一步.     

头发微量元素及钙含量测定的应用价值评价

以125例2～5岁儿童为对象，测定其全血和头发铅、锌、铁、钙含量；以全血铅、锌、铁、钙含量为标准，应用诊断试验评价方法评价头发铅、锌、铁、钙测定的应用价值。结果表明，头发铅测定的灵敏度可达88．3％，应用串联试验，头发铅测定的特异度可提高至81．8％，阳性预测值达69．6％，阴性预测值达78．8％。头发锌测定的灵敏度可达86．1％，特异度为52．4％，阳性预测值75．6％，阴性预测值为68．8％。头发铁测定的灵敏度为72．0％，特异度为77．5％，阳性预测值为83．6％，阴性预测值为63．3％，头发钙测定的灵敏度为78．9％，特异度为69．1％，阳性预测值为69．8％，阴性预测值为78．4％。锌缺乏、铁缺乏、钙缺乏，或铅负荷过高，或数种微量元素缺乏及铅中毒并存是当前严重影响儿童健康成长的常见原因。运用现代检测技术早期发现微量元素缺乏及铅中毒患儿并及时采取防治措施对促进儿童正常生长发育至关重要。头发样品容易采集、运送和保存，因此头发微量元素含量测定适合在中小城镇及农村使用。但其应用价值应进行科学评价。     

Effect of Bee Pollen on the Mechanical and Thermal Properties of Starch Films

The use of casein, starch and bee pollen as biodegradable materials has been promise. The objective of this work was the development and characterization of films containing casein, pollen and starch. The films were obtained by casting process and the solvent evaporation was performed at 40 °C/24 h. The films characterization was carried out by microscopy, thermal analysis, opacity test, mechanical properties and barrier methods. The starch films presented heterogeneous on microscopy analysis. The thermal behaviors of pollen films were similar. The formulation containing only pollen 3% was unable to form film. The introduction of pollen in starch film formulation improved the mechanical characteristic and thermal stability of films.     

质子型离子液体N,N-二甲基乙醇胺丙酸盐的密度、粘度及电导率

在283.15-333.15 K温度范围内, 测量了质子型离子液体N,N-二甲基乙醇胺丙酸盐(DMEOAP)的密度、粘度及电导率. 讨论了温度对密度、粘度和电导率等物理化学参数的影响. 通过经验和半经验方程得到了该离子液体的热膨胀系数、分子体积、标准摩尔熵及晶格能等热力学性质参数. 由电导率和密度计算出了该离子液体的摩尔电导率. 利用Vogel-Fulcher-Tamman (VFT)方程, 将测量的动力粘度和电导率对温度拟合, 得到了动力粘度和电导率随温度变化方程式.并通过Walden规则, 建立了粘度与摩尔电导率之间的联系.     

乳状液膜体系分离提取铜离子

以Span80-对氨基苯磺酸(APS)-NH3液膜体系分离提取Cu2+。最佳分离条件为:制乳搅拌速度3500r/min,制乳时间及乳水混合时间分别为10min和20min,乳水比和油内比分别为0.38和0.44,APS、Span80和液体石蜡浓度分别为11%、4.4%和2.2%,内相NH3和外相HCl浓度分别为4.0mol/L和0.5mol/L。用该体系分离提取了模拟样中的Cu2+。     

Synthesis and performance studies of 1,5-diaminotetrazolium nitrate

1,5-Diaminotetrazolium nitrate (HDATN) was synthesized with 1,5-diaminotetrazole (DAT) as the raw material. The maximum yield of HDATN was 95.3 %. The structure was characterized by elemental analysis, infrared spectrum, nuclear magnetic resonance spectrum and mass spectrum, and the possible fragmentation mechanism was discussed. The morphology was analyzed by SEM. The thermal stability of HDATN was investigated by TG-DSC and DTA techniques. The kinetic parameters including activation energy and pro-exponential factor were calculated by Kissinger equation. The performance of combustion, combustion heat, and formation enthalpy of HDATN were measured. The detonation products of HDATN were most nitrogen, which were analyzed by gas chromatograph and smoke analyzer. The density, formation heat, detonation pressure, and detonation velocity of HDATN were calculated. It exhibited prospective application in environmentally friendly gas generant and explosion field.     

Electrochemical preparation of orthophenylenediamine on different cathodes in sulfuric acid

The electrochemical reduction of nitro group of orthonitroaniline (ONA) is carried out on Pb, Cu, and Sn electrodes. The effect of current density, temperature, and acid concentration on product yield is studied. The polarization curve for ONA in acidic condition is recorded. Under preparative electrolysis, ONA gives a mixture of hydroxylamine and phenylenediamine, the proportion of phenylenediamine increasing with the electrolysis time. The product formation is confirmed by thin-layer chromatography, melting-point test, UV-visible, IR, and NMR methods. The operating conditions are optimized for a good yield of orthophenylenediamine. The catalytic activity of different metals for the reduction of nitro group is discussed. The percent yield of orthophenylenediamine is found to be high on the lead electrode. Published in Russian in Elektrokhimiya, 2007, Vol. 43, No. 2, pp. 215–221. The text was submitted by the authors in English.     

二氧化硅/聚苯乙烯复合微球的制备及作为固相萃取填料的研究

以分散聚合法制备了二氧化硅/聚苯乙烯单分散复合微球,以红外光谱、透射电镜(TEM)、扫描电镜(SEM)等手段对其进行了表征。以合成的二氧化硅/聚苯乙烯作为固相萃取填料制作固相萃取小柱。通过固相萃取与液相色谱联用,测定了水中邻硝基酚、间硝基酚、对硝基酚和辛基酚、壬基酚,考察了固相萃取条件对固相萃取柱性能的影响,选择了最佳的色谱分离条件。结果表明,自制固相萃取小柱对水中硝基酚、烷基酚的萃取率高,与HPLC联用测定结果重现性好,邻硝基酚、间硝基酚、对硝基酚、辛基酚、壬基酚的最低检出限分别为0.90、0.72、0.62、0.38和0.41μg/L。     

Explicit finite difference simulations for accelerating cross diffusion flow over a perpendicular shield with parabolic motion

The heat transfer phenomenon subject to thermos-diffusion effects convey important applications in the heating processes, extrusion systems, chemical processes and various engineering systems. The objective of current work is to observe the contribution of Soret and Dufour effects in oscillating shield for cross diffusion flow. The perpendicular shield with oscillating motion induced the flow. The magnitude of oscillations is assumed to be small so that laminar flow due to oscillating shield has been resulted. The motivations for addressing the thermos-diffusion phenomenon due to oscillating of shield are due to applications in oscillatory pumps, moving surface, metal detectors, power systems etc. The dimensionless problem is obtained via introducing the appropriate set of variables. The numerical outcomes are suggested by using the most interesting explicit finite difference scheme. The physical illustration for flow parameters is presented. Moreover, the aspect of physical quantities involving the flow are graphically reported.     

Study on the Cracking Mechanism of 1,1,2-Trichloro-1,2,2-trimethyldisilane Catalyzed by Aluminum Chloride

The cracking mechanism of 1,1,2-trichloro-l,2,2-trimethyldisilane catalyzed by aluminum chloride is investigated by DFT and MP2 methods. The reactants decompose in two ways, which are competing response. The reaction pathways are both by three steps. And the two reaction channels were both exothermic reaction. The heat of the overall reaction was –293.372 kJ·mol-1. The rate determining steps are the third and first steps, respectively. The Standard Gibbs Free Energy Change is the same, –297.55 kJ·mol-1. The Standard Equilibrium Constant is 1.354 × 1052. The theoretical productivity is high under normal temperature and pressure. The theoretical results agreed well with the experimental data.     

GC-MS联用分析三个品种杨梅树叶的挥发油组分

采用气相色谱-质谱联用技术对木叶、黑炭、东魁3个品种杨梅树叶中的挥发油进行分析比较.3种杨梅树叶挥发油中共检出14种相同成分,这些共有成分的相对含量分别占木叶梅叶、黑炭梅叶和东魁梅叶挥发油总相对含量的53. 3%、48. 4%、55. 15%.3种杨梅树叶挥发油中均舍有多种萜烯,对杨梅果实具有一定抗菌保鲜作用.东魁杨梅树叶挥发油萜烯含量最高,这可能是东魁杨梅果实保鲜期较长的原因;木叶杨梅叶含的特殊香味成分的含量较高,这可能是木叶梅果实香气最浓郁的原因.     

Reversible and irreversible adsorption of surfactants at a hanging mercury drop electrode.

The adsorption-desorption phenomena of surfactants were studied by measuring differential capacity-potential curves in a static solution and differential capacity-time curves in a flowing solution. The surfactants investigated were Aerosol OT, cetylpyridinium chloride, Hyamin 1622, tetrabutylammonium bromide, Triton X-100 and trioctylphosphineoxide. The differential capacity-potential and differential capacity-time curves for these surfactants showed different shapes, with and without peaks. The differential capacity-time curves were used to study the adsorption reversibility of the surfactants at a mercury electrode. The adsorptions of Hyamin 1622 and Triton X-100 were irreversible at all the potentials investigated. The adsorptions of Aerosol OT and trioctylphosphineoxide were irreversible except at the potential more positive than -0.2 V. The adsorption of tetrabutylammonium bromide was almost reversible at any potential investigated. The adsorption of cetylpyridinium chloride was complicated, indicating different orientations of adsorption.     

茚三酮与赖氨酸荧光反应的研究

茚三酮与赖氨酸的显色反应已广泛用于各种样品的测定,但高灵敏的氨基酸荧光测定法的研究还很不够。尽管茚三酮与某些氨基酸的荧光反应已有报道,但反应条件苛刻,反应时间长达60～120min,对赖氨酸的专一测定法尚未见报道^[1~3]。     

Use of oxide minerals to abate fluoride from water

The removal of fluoride from aqueous solutions has been investigated using various oxide ores such as refractory grade bauxite, feed bauxite, manganese ore, and hydrated oxides of manganese ores (WAD). The refractory grade bauxite showed promising results. The studies were carried out as functions of contact time, pH, concentration of adsorbents, concentration of adsorbate, and temperature. The adsorption was rapid during the initial 5 min but equilibrium was attained within 120 min. The adsorption followed first-order kinetics. The present system followed the Langmuir adsorption isotherm model. Various thermodynamic parameters such as free energy, enthalpy, entropy, and equilibrium constants were calculated. The isosteric heat calculations showed that the adsorption process followed a heterogeneous model.