荧光法研究对-二甲氨甲基-杯[8]芳烃与二苯胺磺酸钠包结作用

用荧光法研究了水溶性对-二甲氨甲基-杯[8]芳烃与二苯胺磺酸钠的相互作用。发现当对-二甲氨甲基-杯[8]芳烃加入到二苯胺磺酸钠溶液时,二苯胺磺酸钠的荧光峰发生了明显的蓝移,荧光增强,可能的作用机理是二苯胺磺酸钠中的磺酸根与对-二甲氨甲基-杯[8]芳烃中带正电的氮原子之间有较强的静电作用,二苯胺磺酸钠进入了对-二甲氨甲基-杯[8]芳烃的疏水空腔。同时研究了几种有机溶剂对包结物的荧光强度的影响,初步探讨了其作用机理。     

Convenient Synthesis 1H, 13C NMR Study and X-Ray Crystal Structure Determination of Some New Disubstituted Thiophenes

2,5-, 3,4- and 2,3-Thienylenediacrylic (1, 4 and 7 respectively) were synthesized in one step reaction by catalytic vinylation of the corresponding dibromothiophenes in the presence of cyclohexylamine salt of acrylic acid. 2,4-Thienylenediacrylic acid 10 was prepared by catalytic vinylation of 3-(4-bromo-2-thienyl)acryilic acid.     

Synthesis and Characterization of Ultraviolet Light-Emitting Organic Acids

Three ultraviolet light-emitting organic acids of 3,3′-(4-phenyl-4H-1,2,4-triazole-3,5-diyl)dibenzoic acid (Tz-1), 4,4′,4″-(4H-1,2,4-triazole-3,4,5-triyl)tribenzoic acid (Tz-2), and 4,4′-(4-(4′-carboxy-[1,1′-biphenyl]-4-yl)-4H-1,2,4-triazole-3,5-diyl)dibenzoic acid (Tz-3) were successfully synthesized and fully characterized by the ¹H NMR, the IR absorption spectra, and the X-ray single crystal diffraction. It was found that Tz-1, Tz-2, and Tz-3 could give out the ultraviolet photoluminescent spectra centered at 369 nm, 365 nm and 350 nm, respectively. The luminescence quantum yields of Tz-1 and Tz-2 were measured to be 0.20 and 0.14, respectively. Additionally, the density functional theory (DFT) and the time-dependent DFT calculations were also carried out for Tz-1, Tz-2, and Tz-3.     

α-（5-氟尿嘧啶-1-基甲基甲酰基）氨基-2-甲基丁酸的合成及红外光谱研究

以5-氟尿嘧啶-1-基乙酸、二环己基碳二酰亚胺和L-缬氨酸为原料,1-羟基苯并三氮唑为辅助试剂,通过碳二亚胺法液相偶联法合成了一种新型的α-（5-氟尿嘧啶-1-基甲基甲酰基）氨基-2-甲基丁酸化合物。通过红外光谱、元素分析确证了该种＂5-氟尿嘧啶短肽化合物＂的结构。     

化学发光抑制法测定抗坏血酸

利用抗坏血酸对DTMC H2 O2 化学发光体系的抑制作用 ,研究了对抗坏血酸进行间接测定的可能性。试验发现 ,化学发光猝灭率 (R)与抗坏血酸浓度在 1 0× 10 - 7～ 8 0× 10 - 6 mol·L- 1 范围内呈线性关系 ,检出限达到 8 0× 10 - 8mol·L- 1 (S N =3)。对 1 0× 10 - 6 mol·L- 1 抗坏血酸进行 10次平行测定 ,其化学发光强度猝灭率相对标准偏差为 4 6 %。该猝灭体系不需要额外的掩蔽剂 ,方法简单、选择性好 ,可直接应用于一些食品中微量抗坏血酸的测定。     

一甲基硫脲与支持电解质的阴离子在银电极上共吸附的拉曼光谱研究

本文用电化学现场表面增强拉曼散射光谱（ＳＥＲＳ）技术研究了ＭＴＵ在ＨＣｌＯ４、Ｈ２ＳＯ４和ＨＮＯ３介质中分别与一种或两种无机阴离子的共吸附行为，发现ＣｌＯ－４、ＳＯ２－４和ＮＯ－３等弱吸附无机阴离子均能被ＭＴＵ诱导物理吸附在其质子化了的氨基（ＮＨ＋３）上，这三种无机阴离子被ＭＴＵ诱导物理吸附的强弱顺序是：在电极电位位于－０．２Ｖ～－０．７Ｖ区间时，ＳＯ２－４＞ＣｌＯ－４＞ＮＯ－３，在电位位于－０．８Ｖ～－１．２Ｖ区间时，ＣｌＯ－４＞ＳＯ２－４＞ＮＯ－３。     

SO2-4/TiO2固体酸的红外和拉曼光谱研究

用ＩＲ、Ｒａｍａｎ光谱研究了ＳＯ＾２－４／ＴｉＯ２固体酸在不同烧温度下的结构、晶相转变和表面酸中心。结果表明,ＳＯ＾２－４与ＴｉＯ２表面的结合为螯合式双配结构。当烧结温度小于５００℃时,ＳＯ＾２－４／ＴｉＯ２样品具有较高的结构稳定性,晶相结构以锐钛矿为主,表面Ｂ酸位数目约是Ｌ酸位数目的２倍,当烧结温度大于５００℃时,随着烧结晶度的升高,表面结合的ＳＯ＾２－４逐渐流失,晶相从锐钛矿转变为金红石,表面Ｂ酸位减少并消失。     

Synthesis of mono- and bis-spirooxindole derivatives “on water” using double salt of aluminum sulfate–sulfuric acid as a reusable catalyst

Molecular Diversity - The preparation of double salt of aluminum sulfate–sulfuric acid (Al4(SO4)6·(H2SO4)·24H2O) by the reaction of aluminum sulfate and sulfuric acid in water is...     

Effects of ultrasound on the formation of alpha-benzoylbenzyl cyanide from benzyl cyanide and alkylphenyl ketone from alpha-alkylbenzyl cyanide by potassium superoxide in the presence of crown ether

Ultrasound accelerates the formation of alpha-benzoylbenzyl cyanide and benzoic acid in the reaction of benzyl cyanide with potassium superoxide in the presence of 18-crown-6. Similarly, 4-methylbenzyl cyanide, 4-methoxybenzyl cyanide and 4-chlorobenzyl cyanide gave the corresponding alpha-(4-methylbenzoyl)-4-methylbenzyl cyanide, alpha-(4-methoxybenzoyl)-4-methoxybenzyl cyanide and alpha-(4-chlorobenzoyl)-4-chlorobenzyl cyanide in 25-43% isolated yields under the same reaction conditions. Benzoic, p-toluic, 4-methoxybenzoic and 4-chlorobenzoic acids were also formed in these reactions. No reaction was observed when the mixture was simply stirred. Reflux instead of sonication gave lower yields of the products. However, alpha-alkylbenzyl cyanide produced a high yield of the phenylalkyl ketones when stirred. Interestingly, the corresponding benzoic acid was not formed in these reactions. Possible mechanisms for the formation of alpha-benzoylbenzyl cyanide from benzyl cyanide and phenylalkyl ketones from alpha-alkylbenzyl cyanide are also proposed.     

胺基化合物修饰戊二醛交联壳聚糖树脂的合成及其红外光谱研究

研究了以三聚氯氰为活化剂,正丁胺、二甲胺、三甲胺、三乙胺、苯甲胺、对甲基苯胺、对氨基苯磺酸修饰戊二醛交联壳聚糖的制备及其红外光谱。壳聚糖1 155 cm-1的糖苷键ν_(C—O—C)吸收峰、899 cm-1的环振动吸收峰和1 030 cm-1的伯羟基ν_(C—OH)吸收峰基本不变。在3 430～3 440 cm-1的ν_(O—H)和ν_(N—H)吸收峰稍有变化,1 400～1 384 cm-1的δ_(C—H)吸收峰变化较明显。氨基化修饰交联壳聚糖仲羟基的ν_(C—OH)吸收峰由1 095 cm-1移至1 060～1 070 cm-1。三聚氯氰活化交联壳聚糖在803～812 cm-1和1 584～1 590 cm-1出现均三嗪环骨架振动吸收峰。随取代度和脱乙酰度不同,壳聚糖的酰胺Ⅰ,Ⅱ,Ⅲ峰强度变化明显。伯仲胺修饰交联壳聚糖在1 517～1 530 cm-1出现质子化氨基δ_(N—H)吸收峰,三甲胺、三乙胺修饰交联壳聚糖此峰消失或减弱,但在1 400～1 500 cm-1出现一组ν_(C—N)吸收峰。     

Angular optical characteristics of light scattered by double-layer metal–oxide nanoparticles

The interaction of Tb(III)-2-{[(4-methoxy benzoyl) oxy]} methyl benzoic acid binary complex with nucleosides (adenosine, cytidine, guanosine and inosine) was investigated using UV and fluorescence methods. The reaction of Tb-complex with cytidine, guanosine and adenosine is accompanied by shift to longer wavelength in the absorption band, while there is a blue shift in the absorption band with an enhancement in the molar absorptivity upon the reaction with inosine. The fluorescence intensity of Tb(III)-2-{[(4- methoxy benzoyl) oxy]} methyl benzoic acid binary complex at λ = 545 nm (5D4 → 7F5) was decreased with the addition of the nucleoside molecule following the order: cytidine > inosine > guanosine > adenosine.     

Adamantyl pyran-4-one derivatives and their in vitro antiproliferative activity

Molecular Diversity - Pyran-4-one (maltol, kojic acid and chlorokojic acid 1) esters of adamantan-1-ylacetic acid were prepared through efficient synthetic routes in good yields and evaluated for...     

EPR Spectra of Spin-labeled Fatty Acids in Detergent Solutions: “Immobilized Species” in the Absence of Protein

Electron paramagnetic resonance spectra of 5-doxyl-stearic acid, 3-(2-Dodecyl-1-oxyl-5,5-dimethylpyrrolidin-2-yl)propanoic acid radical (4-proxyl-palmitic acid) and of 3-(1-Oxyl-2,5-dimethyl-5-dodecylpyrrolidine-2-yl)propanoic acid radical (4-azetoxyl-stearic acid) in lipid micelles of nonaethyleneglycol-monododecyl ether (C₁₂E₉) and pentaethyleneglycol-monooctyl ether (C₈E₅) can reveal immobilized components typical of spin-labeled protein-bound fatty acids as well as phospholipids. The occurrence of such species depends on the detergent, the relative orientation of the nitroxide group with respect to the longitudinal axis and the molecular structure of the fatty acid as well as on polarity and ionic strength of the aqueous phase. Whereas 5-doxyl-stearic acid and 4-proxyl-palmitic acid exhibited these highly immobilized components in C₁₂E₉ micelles but not in C₈E₅, only a single relatively mobile component was observed with 4-azetoxyl-stearic acid in both detergents. The immobilized component is lost by the addition of isopropanol but not as much by ethanol and also when distilled water is substituted for the buffer.     

鲜肉中不饱和脂肪酸近红外检测方法优化

不饱和脂肪酸是鲜肉脂肪的基本组成成分，其种类和含量直接影响鲜肉的风味和品质。不同于用时长，破坏样品的气相色谱法，近红外分析可快速，无损地对鲜肉中不饱和脂肪酸进行定量检测。选取了驴肉，牛肉，羊肉和猪肉鲜肉样品共63个，在4 000～12 500 cm-1波段上，分别采集了肉块样品和粉碎口径3 mm的肉糜样品在5，10，15，20，25，30，35 ℃下的近红外漫反射光谱，并使用气相色谱法作为参考检测了样品的不饱和脂肪酸含量。为优化模型性能，比较了不同温度下肉块和肉糜样品全波段光谱的棕榈油酸、亚油酸、油酸、二十四碳一烯酸和总不饱和脂肪酸的偏最小二乘模型参数，发现棕榈油酸和总不饱和脂肪酸的5 ℃肉糜光谱模型，亚油酸的35 ℃和油酸的25 ℃肉糜光谱模型，以及二十四碳一烯酸的15 ℃肉块光谱模型较佳，且温度对模型的影响不具有明显的规律性。在较佳模型的基础上，分别以220，440，881和1 762个变量为窗口区间，使用前向和反向区间偏最小二乘法对波长进行了优选，发现棕榈油酸、亚油酸、油酸和总不饱和脂肪酸以220个变量作为窗口的反向区间偏最小二乘模型，以及二十四碳一烯酸以440个变量为窗口的前向区间偏最小二乘模型较佳，且预测性能均优于全波段PLS模型。其中棕榈油酸的建模波段为：4 425～4 636，4 849～5 272，5 486～5 696.7，7 398.6～7 818，8 031.1～8 666.5，9 947～10 363.6，12 495.5～12 498.4 cm-1；亚油酸的建模波段为：4 000.6～4 423.9，5 273.4～5 698.6，7 398.6～9 090.8，10 576.7～10 787.8，12 495.5～12 498.4 cm-1；油酸的建模波段为：4 000.6～4 423.9，4 637～4 848.2，7 398.6～8 242.3，8 455.4～9 090.8，9 947～10 787.8，12 495.5～12 498.4 cm-1；二十四碳一烯酸的建模波段为：4 849.1～5 272.4 cm-1；总不饱和脂肪酸的建模波段为：4 000.6～4 423.9，4 637～5 698.6，9 097.5～9 515.1，9 940.3～10 575.7，11 646～12 060.6，12 273.7～12 498.4 cm-1。使用偏最小二乘法对优选波长光谱数据进行降维，利用得到的潜在变量作为各指标最小二乘-支持向量机模型的输入，并和各指标的区间偏最小二乘模型进行了性能的比较，发现最小二乘-支持向量机模型的各指标定量结果最优。棕榈油酸、亚油酸、油酸、二十四碳一烯酸和总不饱和脂肪酸最优模型的校正集相关系数和均方根误差，以及留一交叉验证相关系数，均方根误差及相对预测误差分别为：0.974，1.403 mg·(100 g)-1，0.973，1.428 mg·(100 g)-1，4.31；0.99，2.233 mg·(100 g)-1，0.99，2.263 mg·(100 g)-1，7.21；0.982，8.194 mg·(100 g)-1，0.982，8.223 mg·(100 g)-1，5.19；0.921，0.224 mg·(100 g)-1，0.92，0.225 mg·(100 g)-1，2.52；0.996，24.21 mg·(100 g)-1，0.995，26.045 mg·(100 g)-1，10.01。其中，亚油酸、油酸和总不饱和脂肪酸最优模型的交叉验证相对预测误差超过5，棕榈油酸最优模型的交叉验证相对预测误差接近5，二十四碳一烯酸的交叉验证相对预测误差接近3，各指标最优模型的预测性能较为令人满意。研究结果表明，波段优选，偏最小二乘降维以及最小二乘-支持向量机算法的结合可对鲜肉中单个不饱和脂肪酸及总不饱和脂肪酸指标的近红外光谱定量结果进行有效的优化。     

化学发光法测定尿酸

利用尿酸对碱性luminol-H₂O₂-Co2+化学发光体系具有较强的抑制作用,建立了一种测定尿酸的新方法。方法的线性范围为1.0×10-10～7.0×10-6 mol·L-1,检测限(3σ)为1.1×10-11 mol·L-1,RSD 1.9%(n=4,ｃ_s=5.0×10-8 mol·L-1)。该法用于人体血清及尿液中尿酸的测定,结果满意。     

阿奇霉素含量的荷移光谱法测定

用分光光度法分别研究了阿奇霉素与7,7,8,8-四氰基对二次甲基苯醌(TCNQ)和氯冉酸(CL)之间的荷移反应。实验表明：阿奇霉素与TCNQ间的反应在丙酮介质中进行,形成的络合物在743和842 nm有两个吸收峰,表观摩尔吸光系数分别是2.7×104 L·mol-1·cm-1和5.0×104 L·mol-1·cm-1;阿奇霉素与氯冉酸的反应在丙酮介质中进行,形成的络合物在530 nm处有吸收峰,表观摩尔吸光系数2.4×103 L·mol-1·cm-1。用摩尔比法和等摩尔连续变化法测得荷移络合物中阿奇霉素与配体的摩尔比均为1∶2。用以上两种方法测定了阿奇霉素片剂中阿奇霉素的含量,相对标准偏差为1.0%～1.4%(n=6),回收率为97%以上,与标准方法比较结果准确。     

独活浸膏的热裂解产物分析

采用在线热裂解-气相色谱质谱联用技术(Py-GC-MS),模拟卷烟燃吸状态,对独活浸膏进行热裂解,裂解产物经气相色谱-质谱联用仪分析。结果表明:独活浸膏的热裂解产物中共鉴定出51种成分,主要有5-羟甲基糠醛(29.00%)、甲氧基欧芹酚(18.79%)、(Z,Z)-9,12-亚油酸(5.76%)、(E)-2-甲基-2-丁烯酸(3.64%)、5-甲基糠醛(2.79%)、十六酸(2.67%)、2,3-二氢-3,5-二羟基-6-甲基-4H-吡喃-4-酮(1.55%)、糠醛(1.29%)等致香物质,该结果为独活浸膏在卷烟中的应用提供理论依据。     

Natural Bond Orbital(NBO),Natural Population Analysis and Mulliken Analysis of Atomic Charges of 4-Amino-3-Phenylbutanoic Acid

The Molecular Structure of 4-Amino-3-phenylbutanoic acid conformers have been studied in the gas phase. Natural Bond Orbital Analysis (NBO) and Mulliken analysis of atomic charges of 4-Amino-3-phenylbutanoic acid have been performed by DFT level of theory using B3LYP/6-311++G(d,p) basis set. The atomic charges, electronic exchange interaction and charge delocalization of the molecule have been performed by Natural Bond Orbital(NBO) analysis and Natural Population Analysis(NPA) have been constructed at B3LYP/6-311++G(d,p) level.     

具有潜在抗菌活性的环丙沙星衍生物的NMR谱研究

利用核磁共振谱,通过¹H-¹]H COSY, gHMBC and APT (Attached Proton Test)实验对所合成的新化合物1环丙基-6-氟-7-（4-苯乙酰氨基硫代甲酰基-1-哌嗪基）-1,4-二氢-4-氧代喹啉-3-羧酸的NMR谱进行了分析,并对其谱峰进行了详细归属.     

光催化剂SO2- 4/TiO2和TiO2 的光谱行为比较

用ＩＲ、Ｒａｍａｎ和ＤＲＳ光谱研究了ＳＯ＾２－４／ＴｉＯ２光催化剂和ＴｉＯ２光催化剂的光谱行为差别。结果表明,ＴｉＯ２光催化剂的表面只有Ｌ酸中心,而ＳＯ＾２－４／ＴｉＯ２光催化剂表面既有Ｌ酸中心也有Ｂ酸中心。ＴｉＯ２的硫酸化有效地抑制了晶相转变和晶粒度的增加。与ＴｉＯ２相比,ＳＯ＾２－４／ＴｉＯ２光催化剂的锐钛矿相含量较多、晶粒较小、光谱吸收边蓝移,从而增大了光吸收阈值,增强了光生空穴和电子的氧化