聚/N-异丙基丙烯酰胺-铕-噻吩甲酰三氟丙酮的光谱性质及能量传递的研究

首次合成了铕-聚（N-异丙基丙烯酰胺）-噻吩甲酰三氟丙酮（Eu^3＋-PNIPAM—TTA）三元配合物，并用紫外光谱、红外光谱和荧光光谱进行了初步表征。结果表明，Eu^3＋与PNIPAM侧链中氮原子或氧原子配位，Eu^3＋-PNIPAM—TTA体系为三元配合物，而并非PNIPAM与铕-噻吩甲酰三氟丙酮（Eu^3＋-TTA）的混合物；Eu^3＋-PNIPAM—TTA三元配合物的614nm波长荧光强度比Eu^3＋PNIPAM及Eu^3＋-TTA二元配合物分别增强了20900％和183％，在能量传递中，高分子以Foerste，能量传递方式将紫外激发能传递给TTA，再经TTA传递给Eu^3＋，而获得增强的Eu^3＋的特征发射。并考察了不同合成条件下的荧光光谱性质。     

含钐稀土-高分子荧光材料的制备和表征

合成了聚N-异丙基丙烯酰胺-丙烯酸P(NIPAM-co-AAc)共聚微凝胶与Sm(Ⅲ)离子、α-噻吩甲酰三氟丙酮（HTTA)的三元配合物。用激光光散射、Zeta电位、紫外光谱、红外光谱、荧光光谱进行了表征。结果表明．微凝胶粒径为360nm；Sm(Ⅲ)与微凝胶、HTTA之间以配位作用为主；微凝胶、HTTA和Sm(Ⅲ)之间能进行有效的能量传递。配合物的最佳激发波长为348nm，在此激发波长下Sm(Ⅲ)有荧光特征发射。     

微凝胶-铕-α-噻吩甲酰三氟丙酮三元配合物的合成与表征

合成了聚N-异丙基丙烯酰胺-丙烯酸P(NlPAM-co-AAc)共聚微凝胶与Eu(Ⅲ)离子、α-噻吩甲酰三氟丙酮(HTTA)的三元配合物.用透射电镜、激光光散射、Zeta电位、紫外光谱、红外光谱、荧光光谱进行了表征.结果表明,微凝胶粒径为400 nm;Eu(Ⅲ)与微凝胶、HTTA之间以配位作用为主;微凝胶、HTTA和Eu(Ⅲ)之间能进行有效的能量传递.其配合物的最佳激发波长为317 nm,在此激发波长下Eu(Ⅲ)有较强的荧光特征发射.     

盐酸液中钇(Ⅲ)和铕(Ⅲ)的P_(507)溶剂萃取平衡分析(英文)

为了精确预测非理想条件下稀土金属溶剂萃取的平衡分配比,研究了溶于ShellsolD70中的P507溶剂对盐酸液中钇(Ⅲ)和铕(Ⅲ)的萃取平衡,建立化学基模型,并通过非线性最小二乘法确定萃取平衡常数。所建模型涉及了在低酸度区的离子交换反应和高酸度区的溶剂化萃取反应;模型还考虑了稀土金属与Cl-的配位反应,并用萃取剂的有效浓度代替[(HR)2],进而分别对水相和有机相(HR)2的非理想性加以修正。对稀土单元体系,在较宽的初始浓度范围内(稀土浓度最高至0.1mol/L,盐酸浓度0.07-3.00mol/L,萃取剂浓度0.25-1.00mol/L),由模型计算的稀土分配比与实验测得的数据吻合良好,验证了模型的有效性。对于稀土二元体系,该模型能以良好的精度对平衡分配比进行工程预测。     

基于2,5-二甲基三联苯-4’,4’’-二甲酸的稀土配合物及其发光调节和白光发射（英文）

制备和表征了2,5-二甲基三联苯-4’,4’’-二甲酸稀土(Tb~(3+)、Eu~(3+)、Tb~(3+)/Eu~(3+)共掺)配合物。通过荧光光谱可知,使用2,5-二甲基三联苯-4’,4’’-二甲酸作为配体时,Eu~(3+)与Tb~(3+)均能有效发出特征光,将Eu~(3+)与Tb~(3+)共掺,稀土离子发光得到增强。这是由于:1)Tb~(3+)向Eu~(3+)发生能量传递,2)Eu~(3+)猝灭效应减弱。通过调节不同浓度配比的Tb~(3+)与Eu~(3+),可以使配合物的发光从红光变化到绿光,并可以得到发出白光的配合物。发出接近白光的配合物为(Eu0.001Tb0.999)2(TDDA)3(H2O)6,样品色温达到了5199K,显色指数82%。这一稀土配合物可作为单一荧光粉应用于显示、照明等领域。     

提高灰铸铁弹性模量的研究

研究了Si/C比、w(C)量、加Sn微合金化、炉料配比、孕育处理等因素对灰铸铁弹性模量的影响规律,结果显示:(1)在相同的CE条件下,提高Si/C比,弹性模量提高,合适的Si/C比为0.55～0.60;(2)在相同的w(Si)量条件下,降低w(C)量,弹性模量提高;(3)在相同的w(C)、w(Si)量条件下,使用Sn进行微合金化,弹性模量提高,Sn的加入范围为0.04％～0.06％;(4)在相同的w(C)、w(Si)量条件下,采用合成铸铁的配料,能增加初析奥氏体枝晶含量,提高弹性模量;(5)其它条件相同时,优化孕育量和孕育工艺,改善石墨形态、细化共晶团,也可以提高弹性模量.     

SSA 掺杂的苯胺 / 吡咯导电共聚物的制备及结构表征和防腐蚀性能

在磺基水杨酸(SSA)的酸体系中,以过硫酸铵为氧化剂,采用化学氧化聚合法,调整聚合单体配比,制备了SSA掺杂的苯胺/吡咯导电共聚物(PANI/PY-SSA),通过FT-IR,SEM和XRD等测试手段对其分子结构、微观结构和有序化程度进行了表征。同时,将该导电共聚物加入到环氧树脂涂料中,通过Tafel极化曲线和EIS阻抗谱研究了PANI/PY-SSA对低碳钢材料的防腐蚀性能。结果表明,PY共聚改性明显提高了聚苯胺对金属的保护能力,且当聚合单体配比n(AN)∶n(PY)=3∶7时,制备的PANI/PY-SSA防腐蚀性能最好,涂层的Ecorr为-0.335 V,Jcorr为7.972×10-8 A/cm,RC为2.103×105Ω·cm2,CC为1.646×10-8 F/cm2。     

盐酸介质中3,5-二（2-噻吩基）-1,2,4-三唑(2-TAT)对紫铜的缓蚀作用

    采用动电位极化曲线和电化学阻抗谱技术研究了3,5-二（2-噻吩基）-1,2,4-三唑(2-TAT)在1mol/L HCl介质中对紫铜的缓蚀作用.结果表明,2-TAT为阴极型缓蚀剂,阻抗参数的变化表明2-TAT吸附在紫铜表面,形成保护膜,其吸附方式遵循Langmuir吸附等温式.     

不同锰源合成尖晶石型LixMn2O4及其性能

以自制γ—MnO2(SPDM)和电解二氧化锰(EDM)为原料，采用流变相法合成了尖晶石型锂锰氧材料。应用XRD，SEM，TG和DSC等手段研究了原材料性质和配比等因素对合成尖晶石型锂锰氧的结构、粒径、比表面积以及充、放电性能的影响。结果表明，采用流变相法在700-760℃下，反应12h即可得到均相、无杂质、锰平均氧化价态接近3．5的LixMn2O4正极材料；以SPDM为锰源较EMD为锰源在相同条件下合成的尖晶石材料的首次充、放电容量更高，比表面积更大，粒度更小；当原材料中n(Li)／n(Mn)在一定范围内变化时，合成的锂锰氧的晶格常数随材料中锂与锰摩尔比的增大而减小。     

机车车体Q345E钢Ar+CO_2+O_2三元混合保护气体MAG焊接头的组织和性能

选用富氩低氧化性的Ar+CO_2+O_2三元混合焊接气体(即Rich-argon Lower-oxidizability Ar+CO_2+O_2三元混合气体,简称RALO三元混合气体),通过与传统φ(Ar)80%+φ(CO_2)20%二元混合焊接气体(简称二元混合气体)相对比,研究机车车体Q345E钢MAG焊接头的组织和性能。试验结果表明,RALO三元混合气体的焊缝成形较为平滑、美观;三元混合气体的焊缝低温冲击韧性略高于二元混合气体,冲击吸收功A_(kv)(-40℃)值高出约13%;选用三元混合气体或二元混合气体进行焊接,MAG焊接头的组织特征上差别不大,即组织类型相同、形貌特征相似、晶粒尺寸相近,且焊接接头塑性良好,静载拉伸试验试样均断裂于远离焊缝的母材处。     

Synthesis and electropolymerization of N-(4′-carboxyphenyl)-2,5-di(2″-thienyl)pyrrole

N-(4′-carboxyphenyl)-2,5-di(2″-thienyl)pyrrole has been efficiently prepared by the Knorr–Paal condensation of 1,4-di(2′-thienyl)butane-1,4-dione with benzocaine(ethyl-4-aminobenzoate), giving N-(ethyl-4′-benzoate)-2,5-di(2″-thienyl)pyrrole, followed by saponification to give the desired acid. Both new compounds are electropolymerizable, and the polymer films stable to repetitive cycling up to +1.2 V Vs Ag/AgCl.     

Synthesis,emission and spectro-electrochemical studies of bithienylnaphthalene systems

Four new bis(2-thienyl)naphthalene monomers were synthesized and their absorption, emission and redox properties were studied. Thus, 1,5-dimethoxy-2,6-bis(2-thienyl)naphthalene (2,6-BTDMN), 1,5-dimethoxy-4,8-bis(2-thienyl)-naphthalene (4,8-BTDMN), and 1,4,5,8-tetramethoxy-2,6-bis(2-thienyl)naphthalene (2,6-BTTMN) were synthesized by Stille coupling reaction between the respective dibromides and 2-(tributylstannyl)-thiophene while 2,6-bis(2-thienyl)-naphthalene (2,6-BTN, previously prepared from dibromo precursor) and 1,5-bis(2-thienyl)-naphthalene (1,5-BTN) were prepared similarly between the corresponding di-triflates and 2-(tributylstannyl)thiophene. Monomers 1,5-BTN and 4,8-BTDMN reveal only one peak in both absorption and emission spectra, while monomers 2,6-BTN, 2,6-BTDMN, and 2,6-BTTMN show multiple bands for absorption and a single doublet for emission. The oxidation potential values for the monomers range from 0.95 V, for monomer 1,5-BTN to 0.59 V, for monomer 2,6-BTTMN. Electropolymerized monomers, with the exception of 2,6-BTTMN, form good polymeric films on ITO coated glass substrate. They are pale greenish in color in their oxidized states and relatively transmissive and pale yellow in their reduced state. Spectro-optoelelectrochemistry revealed a band gap range of 2.4–2.9 eV. Iodine-doped polymer from chemically polymerized monomer 2,6-BTTMN has a conductivity of 5×10⁻² S/cm.     

Synthesis and luminescence properties of rare earth ternary complexes consisting of Tb(Ⅲ),β-diketones and 1,10-phenanthroline (phen)

In order to study the luminescent properties of ternary rare earth complexes with fl-diketone ligand,three new β-diketone ligands,1-phenyl-3-(p-phenylethynylphenyl)-1,3-propanedione(HPPP), 1-(2-thienyl)-3-(p-phenylethynylphenyl)-l,3-propanedione (HTPP) and 1-(2-furyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HFPP),were synthesized by Sonogashira coupling reaction and Claisen condensation.Three new ternary rare earth complexes,TbL3phen (L = PPP,TPP,or FPP),were synthesized by the reaction of rare earth chloride TbCl3,1,10-phenanthroline (phen) with HPPP,HTPP,or HFPP respectively,in alcohol solution.The compositions were characterized by means of elernental analysis,chemical analysis,and IR spectra.Luminescent properties of the three new complexes have been studied.The results show that the ternary Tb(Ⅲ) complexes only emit the weak fluorescence of the Tb(Ⅲ) ion,which reveals the triplet state energy of the ligands does not match well with the excited state vibrating energy of Tb3+ ion.     

Inhibition investigation and determination of some quantum chemical parameters of 1‐(4‐(dimethylamino)benzylidene)thiosemicarbazide on steel alloys in sulfuric acid medium

The inhibition effect of 1‐(4‐(dimethylamino)benzylidene)thiosemicarbazide (DBT) on the corrosion behavior of 304 stainless steel and mild steel in 0.5 M sulfuric acid solution was investigated using weight loss and potentiostatic polarization methods. The experimental results suggest that DBT inhibits the corrosion of the steels in acid solution. The inhibition efficiencies increased as the concentration of the compound was increased. The calculated inhibition efficiencies from the two investigated methods were in good agreement. Potentiostatic polarization measurements indicate that DBT acts as a mixed type inhibitor for both alloys. The adsorption of inhibitor on the steel surfaces obeys Langmuir adsorption isotherm. The structure of DBT was optimized using PM3 semi‐empirical method. Highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), energy levels, E_LUMO ? E_HOMO (energy gap), dipole moment (µ), and Mulliken charge densities for this molecule were computed and the adsorption mechanism was discussed. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the surfaces of the alloys.     

Synthesis and luminescence properties of rare earth ternary complexes consisting of Tb(III), β-diketones and 1,10-phenanthroline (phen)

In order to study the luminescent properties of ternary rare earth complexes with β-diketone ligand, three new β-diketone ligands, 1-phenyl-3-(p-phenylethynylphenyl)-1,3-propanedione(HPPP), 1-(2-thienyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HTPP) and 1-(2-furyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HFPP), were synthesized by Sonogashira coupling reaction and Claisen condensation. Three new ternary rare earth complexes, TbL₃phen (L = PPP, TPP, or FPP), were synthesized by the reaction of rare earth chloride TbCl₃,1,10-phenanthroline (phen) with HPPP, HTPP, or HFPP respectively, in alcohol solution. The compositions were characterized by means of elemental analysis, chemical analysis, and IR spectra. Luminescent properties of the three new complexes have been studied. The results show that the ternary Tb(III) complexes only emit the weak fluorescence of the Tb(III) ion, which reveals the triplet state energy of the ligands does not match well with the excited state vibrating energy of Tb³⁺ ion.     

Electrochemical and quantum chemical studies of new thiadiazole derivatives adsorption on mild steel in normal hydrochloric acid medium

In this work, a new class of thiadiazole derivatives, namely 3,5-bis(2-thienyl)-1,3,4-thiadiazole (2-TTH) and 3,5-bis(3-thienyl)-1,3,4-thiadiazole (3-TTH), have been studied as possible corrosion inhibitors for mild steel in molar hydrochloric acid (1 M HCl). Weight loss measurements, polarisation curves and AC impedance methods have been used. These studies have shown that the thiadiazole derivatives were very good inhibitors for mild steel in 1 M HCl. Comparison of results showed that 3-TTH was the best inhibitor. The potential of zero charge (PZC) of mild steel was studied by AC impedance method, and the mechanism of adsorption has been predicted. X-ray photoelectron spectroscopy surface analysis with thiadiazole derivatives shows that it chemisorbed at the mild steel/HCl interface. The adsorption of these inhibitors followed Langmuir’s adsorption isotherm. The electronic properties of 2-TTH and 3-TTH, obtained using the AM1 semi-empirical quantum chemical approach, were correlated with their experimental efficiencies using the linear resistance model (LR). These inhibitors are considered as non-cytotoxic substances.     

White emission from a ternary polymer blend by incomplete cascade energy transfer

White light emission was obtained from a light-emitting diode (LED) prepared from a ternary polymer blend (19:1:1 by weight) consisting of poly(9-vinylcarbazole) (PVK), poly(9,9′-dihexlyfluorene-2,7-divinylene-m-phenylenevinylene-stat-p-phenylenevinylene) (CPDHFPV), and poly[2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylenevinylene] (MEH-PPV), where the order of bandgap energy is PVK>CPDHFPV>MEH-PPV. The major component PVK acted not only as the matrix or diluent but also as the excitation energy donor to help the blend generate white light with high efficiency. Good miscibility between PVK and CPDHFPV facilitated the Förster-type excitation energy transfer from PVK to CPDHFPV enhancing the quantum efficiency. However, poor miscibility between CPDHFPV and MEH-PPV resulted in partial energy transfer between the polymers causing the blend to emit two colors simultaneously. Consequently, the incomplete cascade energy transfer in the blend generated a pure white color near CIE coordinate (0.33, 0.33) and the emissive color of this system showed a low sensitivity to the drive voltage.     

Electrosynthesis of 2,7-linked polycarbazole derivatives to realize low-bandgap electroactive polymers

Poly(2,7-carbazole) derivatives have been synthesized because they have more extended conjugation lengths and lower energy bandgaps than poly(3,6-carbazole)s; however, few studies regarding electrochemical synthesis of poly(2,7-carbazole)s have been reported. Here, a series of N-alkylated-2,7-di(2-furyl)carbazoles, N-butyl-2,7-di(2-thienyl)carbazole, and N-butyl-2,7-di(2-(3,4-ethylenedioxthienyl))carbazole, were synthesized to obtain electroactive films of poly(2,7-carbazole) derivatives by electrochemical polymerization. Cyclic voltammetry revealed that these monomers have excellent polymerization activity, due to their low oxidation potentials (<0.57 V vs. ferrocene (Fc/Fc⁺)), and the corresponding polymers exhibit good redox properties. The energy bandgaps of the polymers obtained from optical absorption spectra range from 2.1 to 2.3 eV. Among the polymers, poly[N-butyl-2,7-di(2-(3,4-ethylenedioxthienyl))carbazole] shows the lowest bandgap energy of 2.1 eV, which is lower than that of previously reported poly(3,6-carbazole) analogues (2.4 eV). This polymer exhibits a significant color change from red in the oxidized state to blue in the reduced state during an electrochemical redox process. The electrochemical and optical properties of the monomers are dependent on external heteroaromatic rings attached to the 2 and 7 positions of the carbazole unit.     

Depressing behaviors and mechanism of disodium bis (carboxymethyl) trithiocarbonate on separation of chalcopyrite and molybdenite

This work focuses on the organic depressant, disodium bis(carboxymethyl) trithiocarbonate (DBT), as a selective depressant in copper-molybdenum sulfide flotation separation. Micro-flotation, Zeta potential, FTIR and XPS measurements were carried out to investigate the selective depression mechanism of DBT on chalcopyrite. Zeta potential and FTIR measurements revealed that DBT had higher affinity for chalcopyrite than molybdenite and the XPS results of chalcopyrite before and after treatment with DBT further proved that DBT adsorbed on chalcopyrite surface. The investigation indicates that the mechanism of DBT adsorbing on chalcopyrite is mainly physical adsorption. Locked circuit experiments were carried out and the results showed that DBT could be considered as a cleaner option in commercial Cu-Mo flotation separation circuits.     

Synthesis and photophysical properties of multi-branched ethynyl fluorene-labeled molecules

Two kinds of emissive multi-branched molecule based on an ethynyl fluorene were synthesized by cyclotrimerization method. An ethynyl fluorene-labeled three-armed molecule, DBFP was prepared and the other one, CzDBFP has carbazole terminal groups tethered to DBFP. Their absorption and photoluminescent properties were investigated. The spectral analyses indicate that the molecules bearing ethynyl fluorene moieties as a peripheral group can exhibit highly isolated photophysical properties. The multi-branched molecule, CzDBFP was mixed with 2-{2-[2-(4-diethylamino-phenyl)-vinyl]-6-methyl-pyran-4-ylidene}-malononitrile (DCM1) with an optimum concentration. At the low concentration (0.3 wt%) of DCM1, white emission was observed by incomplete energy transfer process from an excited CzDBFP. At the high concentration (3.0 wt%), red emission was predominantly observed, which was attributed to an efficient Förster energy transfer process.