碳纳米管在催化中的应用进展

简要介绍了碳纳米管的基本结构、特点以及制备方法,概述了碳纳米管在国内用作催化剂或催化剂载体的应用进展情况。     

离子交换树脂非均相催化乙酰化合成乙酰甲胺磷

研究了在间易搅拌釜中以阳离子交换树脂为催化剂，由甲胺磷催化乙酰化合成乙酰甲胺磷。分别考察了不同类型离子交换树脂的催化乙酰化作用。并且研究了搅拌速度，催化剂用量以及反应温度对乙酰化反应的影响。研究结果表明，以NKC9型离子交换树脂在333.15K温度下具有最好的催化乙酰化作用。     

Syntheses and applications of Eu（Ⅲ） complexes of 2-thienyltrifluoroacetonate, terephthalic acid and phenanthroline as light conversion agents

A series of europium(Ⅲ) complexes of 2-thienyltrifluoroacetonate (HTTA), terephthalic acid (TPA) and phenanthroline (Phen) were synthesized. The new complexes Eu(TPA)(TTA)Phen and Eu2(TPA)(TTA)4Phen2 were characterized by elemental analysis, IR spectrum, scanning electron microscope and thermal stability analysis. The results show that the thermal stability of the Eu( Ⅲ ) complexes increases in the following order: the mononuclear complex Eu(TTA)3Phen, the binuclear complex Eu2(TPA)(TTA)4Phen2, the chain polynuclear complex Eu(TPA)(TTA)Phen. And the formation of the binuclear/polynuclear structure of the new complexes appears to be responsible for the enhancement of their thermal and optical stability. In addition, The fluorescence excitation spectra of these new complexes show more broad excitation bands than that of the complex Eu(TTA)3Phen corresponding to their formation. The enhancement of Eu3 fluorescence in the new complexes can be observed by the addition of Gd3 . The bright red luminescent plastics can be obtained when the complex EuGd(TPA)(TTA)4Phen2 is added above 0.5% (mass fraction).     

手性阴离子柱撑水滑石的制备和表征

以水滑石Mg4Al2(OH)12CO3.4H2O为前体,采用返混沉淀方法进行插层组装制备了L-(-)-酒石酸、L-(-)-天冬氨酸、L-(-)-苹果酸柱撑水滑石(LDHs),用X射线衍射、红外光谱及差热分析表征了超分子结构手性层柱材料的结构,结果表明,3种手性酸根阴离子可以插入水滑石的层间完全取代CO32-,得到结晶度高、晶相单一且手性酸根阴离子在层间有序排列的超分子结构手性层柱材料。     

焙烧态水滑石吸附水中钒酸根的研究

采用共沉淀法合成了Mg/Al物质的量比为2∶1的水滑石(LDH),773K煅烧得到其煅烧产物(CLDH),研究了CLDH对钒酸根的吸附性能,分别考察了吸附剂用量、钒酸根浓度、吸附时间和温度等因素对钒酸根吸附效果的影响,并探讨了吸附热力学。结果表明,CLDH对钒酸根有很强的吸附能力,在293～313K温度范围内,CLDH的最大吸附量随着温度的升高而逐渐增大(79.8～92.9mg/g),吸附等温线很好地符合Langmuir方程(R20.999),吸附自由能(ΔG0)为-2.47～-3.81kJ/mol,是自发的物理吸附过程;CLDH吸附钒酸根为熵增过程,熵变为67.23J/(mol·K)。     

铕Ⅲ-对苯二甲酸-2-噻酚甲酰三氟丙酮多核体系的荧光增强及其应用

以对苯二甲酸(TPA)与2-噻酚甲酰三氟丙酮(HTTA)为配体研究了Eu3+在其乙醇溶液中的荧光增强效果。研究结果表明,在pH为6.8的乙醇溶液中,对苯二甲酸与2-噻酚甲酰三氟丙酮混合配体的敏化可使Eu3+荧光强度提高三个多数量级。在三苯基氧化膦(TP-PO)存在的条件下,稀土La3+、Gd3+、Y3+与Eu3+-TPA-TTA-TPPO形成的多核发光体系具有很强的发光效果,据此建立了测定稀土样品中痕量铕的新方法,方法线性范围为4.0×10-8～3.0×10-6mol/L,检出限达6.0×10-10mol/L。用此体系对4个人工合成的稀土混合物样品进行分析,相对误差为1.7%～3.8%,相对标准偏差为1.7%～3.5%。     

Human plasma protein binding of water soluble flavonoids extracted from citrus peels

The human plasma protein binding of water soluble flavonoids in the peels of five spices of citrus fruits was studied by ultrafiltration combined with HPLC.The flavonoids were extracted separately by hot and cold water,and higher total flavonoid contents were detected in the former extracts than the latter ones.All the extracts show significant scavenging abilities to both ABTS and DPPH free radicals,which indicates the health benefits of the water extracts of citrus fruits peels.For DPPH radical,the IC50values of hot extract follow as Navel orange（NO）≈Mandarin orange（MO） Lemon（LE） Lo tangerine（LO） Pomelo（PO）,while the rank is NO POLE≈MOLO for ABTS radical.The HPLC results reveal that the kinds and contents of the flavonoids detected in the extracts are different among the species.MO extract has the most neohesperidin dihydrochalcone of 118.76 μmol/L and quercetrin of 211.81 μmol/L of which are much more than the rest extracts.Pomelo extract has the most plentiful flavonoids of naringin with a concentration of 303.28 μmol/L.The high contents of myricetrin and dihydromyricetin which both are potent free radical scavengers may explain the highest free radical scavenging activity of the NO extract.The plasma binding rates decrease with the increasing concentrations of flavonoids,and the flavonoids having plenty hydroxyl groups on both A ring and B ring of the molecular skeleton have relative higher plasma binding rates.In addition,the plasma binding rates of flavonoids with saturated C3-C4 bond decrease significantly with the increasing concentrations.     

Syntheses and cofluorescence of complexes of Eu（Ⅲ）/Y（Ⅲ） with terephthalic acid, 2-thenoyltrifluoroacetone and trioctylphosphine oxide

A series of Eu（ Ⅲ）/Y（Ⅲ） complexes of terephthalic acid（TPA） with 2-thenoyltrifluoroacetone（HTTA） and trioctylphosphine oxide（TPPO） were synthesized. Compositions of these complexes are revealed to be Eu2（1-x）Y2x（TPA）（TTA）4- （TPPO）4 or EU1-xYx（TPA）（TTA）（TPPO）2. Their 1R spectra, fluorescent spectra and the thermal and optical stability were studied. The fluorescent excitation spectra of these complexes show more broad excitation bands than those of Eu2（TPA）3（TPPO）4 and Eu（TTA）3（TPPO）2 corresponding to their formations. In addition, both the binuclear complex EuY（TPA）（TTA）4（TPPO）4 and the chain complex EU0.4Y0.6（TPA）（TTA）（TPPO）2 present higher thermal stability and better optical stability than the mononuclear complex Eu（TTA）3（TPPO）2 does. And their thermal and optical stabilities are preferably interpreted from the binuclear structure together with the chain polynuclear structure of the complexes. The fluorescence enhancement of cofluorescence Y^3＋ ions to the Eu（Ⅲ） complexes is clear. The optimum content of Y^3＋ is 0.6 （molar fraction） for the chain complexes Eu1-xYx（TPA）（TTA）- （TPPO）2 and 0.5 for the binuclear complexes Eu^2（1-x）Y2x（TPA）（TTA）4（TPPO）4. The formation of polynuclear structure of the complex Eu1-xYx（TPA）（TTA）（TPPO）2 appears to be responsible for the good cofluorescence effect of Y^3＋ ions.     

光学纯酒石酸柱撑Mg-Al水滑石的制备及应用

以镁铝水滑石为前体,乙二醇为分散介质,采用离子交换法进行插层组装制备了光学纯酒石酸柱撑水滑石.采用X射线衍射、红外光谱及差热分析对样品进行了表征.结果表明:通过控制离子交换条件,光学纯酒石酸根阴离子可以插入镁铝水滑石层间,完全取代CO3 2-离子,形成具有超分子结构的稳定光学纯酒石酸柱撑水滑石,并将其应用于特布他林对映体的手性萃取过程;在萃取过程中加入光学纯酒石酸柱撑水滑石粉末,能明显提高对映体的选择性,对映体选择性分离因子最大值可达1.2.     

萘普生分子印迹拆分过程热力学研究

采用4-乙烯基吡啶为功能单体,三甲氧基丙烷三甲基丙烯酸酯为交联剂,制备出(S)-萘普生的分子印迹聚合物,并将其用作高效液相色谱固定相,对其进行了评价.研究了流动相流速、不同功能单体和柱温对拆分效果的影响,测定出分离过程的热力学参数,证明萘普生分子印迹拆分过程是焓控过程.