对硝基苯甲醛缩对氨基乙酰苯胺希夫碱的室温固相合成及其可逆热致变色研究

以对硝基苯甲醛和对氨基乙酰苯胺为原料,通过室温固相反应合成了一种希夫碱衍生物,用元素分析、核磁共振等方法对产物进行了表征,并利用DSC技术对其变色过程进行了研究。结果表明,采用室温固相反应的方法合成的化合物结构和目标产物一致,且产率较高,熔程较短,纯度较高,反应效果理想。标题化合物作为热致变色材料具有变色敏锐、颜色对比明显、可逆性好以及变色温度高等特点,是一种具有良好应用前景的可逆热致变色材料。     

几种席夫碱衍生物的室温固相合成及可逆热致变色研究

以2,4-二硝基苯肼与取代苯甲醛为原料,通过室温固相反应合成了6种席夫碱衍生物,用元素分析、核磁共振等方法对产物进行了表征,并利用DSC技术对其变色过程进行了研究。用密度泛函理论的B3LYP方法对产物的分子结构进行优化,从理论上探讨了他们的变色机理。研究表明,此类席夫碱衍生物作为热致变色材料具有变色敏锐、颜色对比明显、可逆性好以及变色温度高等特点,是一类具有良好应用前景的可逆热致变色材料。     

液相色谱-质谱/质谱联用技术分析固相合成奈米非肽及其副产物

利用高效液相色谱-串联质谱(HPLC-MS/MS)联用技术分析固相合成奈米非肽(H-4F-Phe-Hyp-Arg-Gly-Trp-NH2)粗产物,探讨HPLC-MS/MS技术在固相多肽合成产物和副产物分析中的应用.RP-HPLC分析采用0DS柱(Kromasil 4.6mm×250mm),流动相A为0.1%甲酸水溶液,B为乙腈.洗脱梯度为:0～40min,B相由15%到60%,流速0.5mL/min,检测波长214nm.电喷雾离子源(ESI),正离子检测模式分析.粗产物中主成分即为目标五肽-奈米非肽,根据测量结果改进了实验方案,主成分含量由65.8%提高到80.4%.     

球磨-固相烧结合成WS_2六方纳米片及其摩擦学性能

以硫粉和钨粉为原料,通过球磨-固相烧结的方法合成WS2六方纳米片,采用X射线衍射仪(XRD)、扫描电镜(SEM)和透射电镜(TEM)对产物的物相、形貌和微观结构进行了表征,根据试验结果提出了其可能的生长机理,并通过摩擦试验对其摩擦磨损性能进行评价。结果表明:制备WS2六方纳米片的最佳工艺条件为700℃保温1h,在该条件下合成的WS2纳米片厚度均匀,约为100nm,直径在1~2μm;在基础油中添加了WS2六方纳米片后,摩擦因数降低,有效改善了基础油的摩擦学性能。     

Characterization of Thermodynamic Properties of 3-N-Butyl-6-(1-Decyl Olefinic Acid Base)-4-Cyclohexene Diacid by Inverse Gas Chromatography

The dispersive-free energy and acid–base forces of 3-n-butyl-6-(1-decyl olefinic acid base)-4-cyclohexene diacid were investigated by inverse gas chromatography. Five nonpolar and 5 polar solvents were used between 353 K and 413 K. By using the retention times of nonpolar and polar probes in the infinite dilution region, adsorption thermodynamic parameters, including the adsorption enthalpy by acid-base interactions and the molar-free adsorption energy of acid-base interaction were evaluated. The results showed that 3-n-butyl-6-(1-decyl olefinic acid base)-4-cyclohexene diacid has low surface energy dispersion and is a Lewis amphoteric material with predominantly basic character. These results were confirmed by the Lewis acidity and basicity constants. Because the surface energy dispersion of inorganic fillers was higher than modified inorganic fillers, and the compatibility of inorganic fillers with the polymers was poor, the inorganic fillers should be modified with 3-n-butyl-6-(1-decyl olefinic acid base)-4-cyclohexene diacid to reduce the surface energy.     

1-(4-甲基)苯基-3-苯基-3-(N-苯基)胺基-1-丙酮的合成及波谱分析

本文报道了1—(4—甲基)苯基—3—苯基—3—(N—苯基)胺基—1—丙酮的合成步骤及其红外光谱、核磁共振谱,并分析了红外光谱、核磁共振谱各主要谱带及归属。     

ZrO_2含量对超重力下燃烧合成快速凝固Al_2O_3/ZrO_2(4Y)复合陶瓷的影响

采用超重力下燃烧合成技术,以快速凝固方式制备了Al2O3/ZrO2(4Y)复合陶瓷,用XRD、SEM与EDS等研究了ZrO2含量对复合陶瓷显微结构和性能的影响。结果表明:当复合陶瓷中ZrO2质量分数在34.1%~46.4%时,复合陶瓷的显微结构主要为棒晶;当质量分数为49.6%~53.7%时,其显微结构主要为形状不规则的ZrO2球晶;随着ZrO2含量的增加,复合陶瓷的相对密度逐渐降低(最高可达94.3%),而硬度和断裂韧度均呈先增高后降低的趋势,当ZrO2质量分数为42.6%时,硬度和断裂韧度均达到最高值,分别为13.1 GPa和13.5 MPa.m1/2。     

气相色谱-质谱法同时测定蜂蜜中的双甲脒及其代谢物残留

建立了一种用气相色谱．质谱法(GC-MS)测定蜂蜜中的双甲脒及其代谢物(2，4-二甲基苯胺)残留的方法。蜂蜜样品用pH为11．0的水溶液溶解，其中的双甲脒和2，4-二甲基苯胺残留用正己烷超声波提取后直接用GC-MS测定。样品添加浓度在10μg／kg～200μg／kg时，双甲脒和2，4-二甲基苯胺的添加回收率在60％～120％之间，检出限均为10μg／kg。     

金属/陶瓷复合材料的原位合成及其结构研究

以铝镁合金、高纯石英棒为原料，采用原位合成法在1473K氮气氛下保温2h制备了Al（Si）／AlN／MgAl2O4复合材料。采用XRD、SEM和EDX等方法分析了所得材料的相组成与显微结构。结果表明：复合材料的物相为MgAl2O4、Al-Si、AlN、Mg2Si和Si；在铝与SiO2界面上形成的Al2O3与基体合金中的镁反应生成块状的MgAl2O4尖晶石晶体，在复合材料内部发现均匀分布的AlN晶须，部分氧、铝、镁、铁形成化合物与硅一起均匀弥散分布于复合材料中。     

Si_3N_(4p)-SiC_w/MoSi_2复合材料的强韧化效果与机制

通过显微组织观察和力学性能测试,对SiC晶须和Si3N4颗粒复合强韧化MoSi2的效果及其作用机制进行了初步研究和探讨。结果表明:复合材料中的SiC晶须和Si3N4颗粒的加入可大幅提高其抗弯强度、断裂韧度和维氏硬度;弥散强化和细晶强化是复合材料强度提高的主要机制,抗弯强度达到427 MPa;通过晶粒细化、裂纹偏转和分叉等机制的综合作用使复合材料增韧,室温断裂韧度达到10.4 MPa.m1/2。     

Mass spectrometry for detection of 4-hydroxy-trans-2-nonenal (HNE) adducts with peptides and proteins

Despite the great technical advancement of mass spectrometry, this technique has contributed in a limited way to the discovery and quantitation of specific/precocious markers linked to free radical-mediated diseases. Unsaturated aldehydes generated by free radical-induced lipid peroxidation of polyunsaturated fatty acids, and in particular 4-hydroxy-trans-2 nonenal (HNE), are involved in the onset and progression of many pathologies such as cardiovascular (atherosclerosis, long-term complications of diabetes) and neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, and cerebral ischemia). Most of the biological effects of HNE are attributed to the capacity of HNE to react with the nucleophilic sites of proteins and peptides (other than nucleic acids), to form covalently modified biomolecules that can disrupt important cellular functions and induce mutations. By considering the emerging role of HNE in several human diseases, an unequivocal analytical approach as mass spectrometry to detect/elucidate the structure of protein-HNE adducts in biological matrices is strictly needed not only to understand the reaction mechanism of HNE, but also to gain a deeper insight into the pathological role of HNE. This with the aim to provide intermediate diagnostic biomarkers for human diseases. This review sheds focus on the "state-of-the-art" of mass spectrometric applications in the field of HNE-protein adducts characterization, starting from the fundamental early studies and discussing the different MS-based approaches that can provide detailed information on the mechanistic aspects of HNE-protein interaction. In the last decade, the increases in the accessible mass ranges of modern instruments and advances in ionization methods have made possible a fundamental improvement in the analysis of protein-HNE adducts by mass spectrometry, and in particular by matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) tandem mass spectrometry. The recent developments and uses of combined analytical approaches to detect and characterize the type/site of interaction have been highlighted, and several other aspects, including sample preparation methodologies, structure elucidation, and data analysis have also been considered.