Syntheses,structure and photoluminescent properties of lanthanide oxalatosulfocarboxylate coordination polymers

Hydrothermal reactions of oxalic acid(H2ox) and 2-sulfobenzoic acid(H2L) with lanthanide oxide or hydroxide yielded five lanthanide oxalatosulfocarboxylates.They have a general formula [Ln2L2(ox)(H2O)6]n[Ln = La(1),Nd(2),Eu(3),Gd(4),Tb(5)].Their structures were characterized by single crystal X-ray diffraction,powder X-ray diffraction(PXRD),infrared(IR) spectroscopy,elemental analysis(EA),and thermogravimetric analysis(TGA).1-5 are isostructural coordination polymers and feature one-dimensional(1D) chains,which are extended into 3D supramolecular frameworks through inter-chain hydrogen bonds between coordinated H2O donors and oxygen acceptors from carboxylate,sulfonate and oxalate groups.In addition,the solid-state photoluminescence properties of the Nd(2),Eu(3) and Tb(5) derivatives have been measured at room temperature.The Eu and Tb-containing coordination polymers(CPs) exhibit intense red and green luminescence emissions,respectively,with lifetimes in the order of millisecond.     

Study on synthesis and deplete harmful radical of cobalt prophyrins as the mimic of enzyme

The four cobalt porphyrins [Co (3, 4, 5-MeO-TPP) (1); Co (TTP) (2); Co (4-Cl-TPP) (3); Co (4-HSO₃-TPP) (4)] were synthesized and considered as two mimic of superoxide dismutaes (SOD) and catalase (CAT). The catalytic efficiency of them on deplete the harmful radical have been proved using riboflavin-methionine photoreduction method in the concentration range of 10⁻⁶∼10⁻⁵ mol/L. The catalytic efficiency of them at decomposing H₂O₂ has been performed by spectrophotometer. The percentage of decomposing H₂O₂ while the increasing the concentration of the imitating compounds. The lipid peroxidation produced in liver homogenated of mice was determined by spectrophotometer detecting the content of MDA.     

Investigation on the coordinate structures of the rare earth metal complexes with edta and cydta ligands

0　IntroductionThegreatattentionhasbeenpaidtorareearthorradioactiverareearthmetalcomplexesfortheirvariousbiologicactivi ties[1 3] .Forexamples,theradioactiverareearthmetal1 53SmⅢ com plexeswerewidelyusedfortumourtherapyofbrain ,liver,lung ,heartandbonetissues[4 5] ;forrareearthmetalEuⅢandTbⅢemitinguniquefluorescence ,theircompoundswereappliedfordiagnosesofvariousdiseases[6 ,7] ;forrareearthmetalGdⅢcontainingthemosthigh spinsingleelectrons,itscomplexeswereusuallyusedforcontrastagentsofmag…     

Nb(100)表面吸附和解离氮气的密度泛函理论计算

【目的】研究多个氮气分子吸附于Nb(100)表面的问题.【方法】采用基于密度泛函理论的总能计算方法研究Nb(100)表面吸附多个氮气分子。【结果】得到0.25,0.50,0.75覆盖度(ML)下氮气分子吸附Nb(100)表面的结构,能量,振动频率以及表面功函数等性质,并进一步讨论了氮气分子在Nb(100)表面吸附与分解的物理机制。【结论】吸附在Nb(100)表面的氮气分子容易发生解离,部分氮气分子以分子态的形式吸附,而部分氮气分子则分解成原子吸附于铌表面。     

Half-sandwich β-diketonato complexes of zirconium and their application as catalysts to ethylene polymerization

The bis(β-diketonato) Zr complexes CpZr(acac)2Cl (acac = acetylacetonato) (1) and Cp*Zr(acac)2Cl (2) can be synthesized by the reac-tion of Cp′ZrCl3(Cp′ = Cp or Cp*) with 2 equiv of lith-ium acetylacetonate. CpZr(acac)2Cl (1) can be quan-titatively prepared by treatment of Cp2ZrCl2 with ex-cess acetylacetone. The tris(β-diketonato) Zr com-plex CpZr(tfac)3 (tfac = trisfluoroacetylacetonato) (3) has been prepared by treatment of CpZrCl3 with so-dium trisfluoroacetylacetonate. The replacement of both chlorine atoms and one Cp group from zir-conocene dichloride by nonfluorinated diketone,acetylacetone,readily occurs at room temperature in triethylamine medium,offering the tris(β-diketonato) Zr complex CpZr(acac)3 (4). The complexes were characterized by 1H NMR spectroscopic methods. In addition,the molecular structures of complexes 3 and 4 have been determined by X-ray diffraction methods. When activated by excess methylaluminoxane (MAO),these complexes were active for ethylene polymerization,offering polyethylenes with high mo-lecular weights and narrow molecular weight distribu-tions. Complex 4 showed a very high ethylene po-lymerization activity of up to 7100 kg PE/mol Zr·h at 5 atm. Complexes 1 and 2 were also active for ethyl-ene/1-hexene copolymerization.     

Quantum chemical studies on tuning the second-order nonlinear optical molecular switching of triarylborane derivatives

In this work, density functional theory (DFT) combined with the finite field (FF) method has been adopted to analyze the second-order nonlinear optical (NLO) properties of the triarylborane (TAB) derivatives obtained by introducing different inductive electron groups into the phenylene ring of the TAB (RTAB, where R=2-C6H5-C2B10H10(1),R=F(2), R=Me(3),R=NO2(4),R=NH2(5)). The static first hyperpolarizabilities (βtot) of the RTAB molecules can be switched by binding one F- to the boron center (RTAB′) or one-electron reduction (RTAB"). The DFT-FF calculations show that the βtot values of 2′, 3′ and 5′ decrease while those of 1′ and 4′ increase compared with the values of their neutral molecules, which was attributed to the fact that the charge transfers of 2, 3 and 5 become smaller and those of 1 and 4 become larger by binding one F- ion to the boron center, according to time-domain DFT (TD-DFT) analysis. However, the incorporation of one electron enhances the second-order NLO properties of the RTAB molecules remarkably, especially for system 1. It is notable that the βtot value of reduced form 1″ is 508.69×10-30 esu, i.e. about 578 times larger than that of system 1. Frontier molecular orbital (FMO) and natural bond orbital (NBO) analyses suggest that the reversal of the charge distribution between the neutral molecules and their reduced forms leads to low HOMO-LUMO energy gaps (E0) and thus large βtot values for the reduced forms.     

Synthesis,characterization and photoluminescence of aluminum <Emphasis Type="Italic">N</Emphasis>-aryloxo functionalized <Emphasis Type="Italic">β</Emphasis>-ketoiminate complexes

The synthesis, characterization and luminescent properties of aluminum complexes containing a dianionic N-aryloxo functionalized β-ketoiminate ligand are presented. 4-(2-Hydroxy-5-R-phenyl)imino-2-pentanone (R = Me, L¹H₂; R = tert-butyl, L²H₂) ligands reacted with AlEt₃ in tetrahydrofuran to give the aluminum complexes (L¹AlEt)₂ (1) and (L²AlEt)₂ (2) in reasonable isolated yields. X-ray diffraction revealed that complexes 1 and 2 have solvent-free centrosymmetric dimeric structures, and each aluminum center has distorted trigonal bipyramidal geometry. At room temperature, complexes 1 and 2 exhibit blue photoluminescence in acetonitrile with maximum emission wavelengths of 419 and 413 nm, respectively.     

Preparation of (R)- and (S)-2-Allyl-1, 3, 2-dinaphtho (α, β) [d.f] dioxaborepin and their reactions with aldehydes

(R)- and(S)-2-Allyl-1,3,2-dinaphtho (α,β) [d.f] dioxaborepin ((R)-2 and(S)-2) have been first prepared by the reaction of(R)-(+)- or(S)-(−)-1, 1′-bi-2-naphthol and triallylborane in THF at room temperature, respectively.(S)-2 and(R)-2 are sensitive to moisture and oxygen in air and disproportionate easily to triallylborane and 1,1′-bi-2 naphthyl bis (1,1′-bi-2-naphtholborate) at ambient temperature. However, THF is a stabilizer for them. The reactions of(R)-2 or(S)-2 and some aliphetic or aromatic aldehydes in CH₂Cl₂ at −78°C for several hours afforded β-alkylenyl alcohols in up to 84.8%ee. Among them, optically active 1-(3, 5-dichlorophenyl)-3-butenol and 1-(2-methoxyphenyl)-3-butenol were first prepared Foundation item: Supported by the National Natural Science Foundation of China (29972033) Biography: Liu Dejun (1973), male, Ph. D, research direction: asymmetric synthesis     

Fabrication and Photocatalytic Characteristics of TiO2 Films on Silicon Substrates

Silicon ( 111 ) and Silicon (100) have been employed for fabrication of TiO2 films by metal organic chemical vapor deposition (MOCVD). Titanium (Ⅳ) isopropoxide (Ti[O (C3H7)4 ])was used as a precursor. The as-deposited TiO2 films have been characterized with Field emission scanning electron microscopy (FE-SEM), X ray diffraction (XRD) and atomic force microscopy (AFM). The photocatalytic properties were investigated by decomposition of aqueous orange Ⅱ. The crystalline and structural properties of TiO2 film had crucial influences on the photodegradation efficiency. For MOCVD in-situ deposited films on Si substrates, thephotoactivities varied following a shape of “M”: At lower (350 ℃ ) middle (500 ℃) and higher (800 ℃) temperature of deposition, relative lower photodegradation activities have been observed. At 400 ℃ and 700 ℃ of deposition, relative higher efficiencies of degradation have been obtained, because one predominant crystallite orientation could be obtained as deposition at those two temperatures, especially a single anatase crystalline TiO2 film could be obtained at 700 ℃ growth.     

Synthesis and Structure of Polypyrrole Derivatives／V2O5 Nanocomposites

Poly ( N, N, N-trimethyl ( 2-pyrrol-l-yl ) ethyl ammonium iodide )/V2O5 ( PTPAI/V2O5) nanocomposites were synthesized by sol-gel method. This method involved formation of vanadium pentoxide xerogel in the prcscnce of polypyrrole derivatives solution. X-ray diffraction(XRD) indicated that the polypyrrole derivative particles encapsulated in the fibrous V2O5 network and the layered distance significantly increased from 1. 077 39 to 1. 354 56 nm. The interaction between polypyrrole and V2O5 in the ‘nanocomposites‘ was characterized by IR spectroscopy. The Scanning Electron Microscope(SEM) micrographs reveal the structural contrasts between the hybrid materials and the pristine vanadium oxide xerogel.     

A Novel Degradation Pathway of Zn（dmid） （ phen）2 in Pyridine

The light-oxidation degradation processes of Zn(dmid)(phen)2(dmid = 4, 5-dimercapto-1,3-dithiole-2 one, phen = 1,10-phenanthroaline) in pyridine solvent has been monitored, h has been found under the light, dmid^2- of Zn(dmid)(phen)2 in pyridine solution could generate NCS^- and NCS^-replaces dmid^2- to form Zn(NCS)2 (phen)2 simultaneously. The crystal structure of Zn(NCS)2 (phen)2 has been determined. In the crystal of Zn(NCS)2 (phen)2. two NCS^- ligands are arranged in syn-configuration, and there is strong π-π interaction between the two adjacent parallel phen.     

Preparation and kinetics of the thermal decomposition of nanosized CuC2O4−ZnC2O4·2H2O

The physical mixture of nanosized CuC₂O₄−ZnC₂O₄·2H₂O, as precursors of CuO−ZnO, have been prepared by the one-step solid state reaction method at room temperature. The thermal decomposition processes taking place in the solid state oxalate mixture of nanometer CuC₂O₄−ZnC₂O₄·2H₂O have been studied in static air using TG, DSC, XRD and TEM techniques. TEM showed that the grain size of the decomposition product is 5–15 nm. The values of the activation energyE _α were determined using the isoconversional procedure of KAS method and the Ozawa method. The most possible mechanism functionf(α) of the thermal decompositions of nanosized CuC₂O₄−ZnC₂O₄·2H₂O are defined using the comparative method, function models of the decomposition of CuC₂O₄ and ZnC₂O₄ follow the same mechanism function “Avrami-Erofeev equation”. The pre-exponential factorA is obtained on the basis ofE _α andf(α), thus the thermal analysis kinetic triplet of the decompositions of nanosized CuC₂O₄−ZnC₂O₄·2H₂O are determined. Foundation item: Supported by the key Natural Science Fund of Deparartment of Science and Technology of Hubei Province (2001ABA099). Biography: CHEN Donghua(1946-), male, Professor, research direction: material synthesize and thermal, analysis kinetics.     

Treatment of Wastewater Containing Polyacrylamide Using Three Dimensional Electrodes

A method using three-dimensional electrode is applied to treat wastewater in oil fields, which contains polyacrylamide (PAM), for analogue. A best condition for electrolysis (I=1.0 A, t=90 min, c=0.1%, m=980 g,φ =5 mm, d=5.0 cm) has been determined, under which the COD removal efficiency reached 96.0%, COD containing in wastewater reduced to 64.3 mg/L from 1 622.9 mg/L, the figure before treatment. Three categories of PAM-containing wastewater in production practice have been treated with the COD removal ratios being 87.5%, 82.4% and 84.7% respectively. Presence of H_2O_2 and·OH are detected by means of Ti(Ⅳ)-5-Br-PADAP technique and colorimetry respectively. The concentration is positively proportional to the COD removal ratio and increases in accordance with increment of time of electrolysis and current.     

CdS光化学修饰介孔TiO2及其增强的可见光催化活性

[目的]提高介孔TiO₂材料的光催化活性。[方法]采用蒸发诱导自组装法(EISA),以四氯化钛和钛酸丁酯为钛源,嵌段共聚物P123(EO₂₀PO₇₀EO₂₀)为模板剂,制备介孔TiO₂。用光化学修饰法将CdS掺进介孔TiO₂中,合成对可见光有较好响应的复合材料,并利用X射线衍射(XRD)、透射电镜(TEM)、原子吸收分光光度法(AAS)和光催化等手段对样品进行表征。[结果]XRD和TEM结果表明成功合成有序的六方介孔材料;AAS确定复合材料中Cd的含量为0.96mg/g;光催化于500 W氙灯下以2×10^-5mol/L次甲基蓝(MB)为模型污染物,结果显示CdS/TiO₂复合材料的可见光催化活性明显提高。[结论]光化学修饰法制备的介孔CdS/TiO₂复合材料可增强其可见光催化活性。     

Optical Properties of Ru（bipy）2 （dppx）^2＋ in Different Environments

The emission spectra of Ru（bipy）2 （dppx）^2＋ in different environments has been studied. It was found that the solvent polarity and the ability of donating and transferring proton are the important factors in predicting luminescence intensity in different systems. The increasing content of water in the organic solutions of Ru（bipy）2 （dppx）^2＋ leads to de crease in emission intensity that follows the Perrin sphere of quenching model. The effect of base content of DNA on the fluorescence spectra of Ru （bipy）2 （dppx）^2＋ has also been studied.     

Novel Substitution Reactions of 5-（4-Nitrophenyl）-10,15,20-TriphenylPorphyrin with Nucleophilic Reagents

Substitution reactions of 5-（4-nitrophenyl）-10, 15,20-triphenylporphyrin （NO2 TPP） and its metal complexes with different nucleophilic reagents were studied for preparing asymmetric porphyrin. The reaction products are different with the nucleophilic reagents changing, and three different products were found. The first obtaining product was diporphyrin when NO2 TPP reacted with sodium phenoxide or diphenoxide in DMF solution; The second was reduced product 5-（4-aminophenyl）-10, 15, 20-triphenylporphrin-M （Ⅱ） when the metal （Ni,Zn） complex of NO2 TPP reacted with above nucleophilic reagents, as well as NO2 TPP reacted with lithium mercaptoethanolate or lithium thiophenolate; The third product CNTPP was achieved with the substitution of nitro group by cyanic anion when NO2 TPP reacted with radium cyanide. Above results were explained with reduction and single electron transfer reaction respectively.     

Spectroscopic characterization and stereodynamics of ferrocenylselenoethers Pt(II), Pd(II), Rh(III) complexes

Ferrocenlyselenides (C₅H₅FeC₅H₄SeR, Fe(C₅H₄SeR)₂) and their complexes of metal Pt, Pd, Rh (R=undecenyl, benzyl, phenyl) have been prepared. The spectroscopic characterization has been examined by mass spectrum, XPS, IR and NMR. IR, NMR spectra of C₅H₅Fe C₅H₄Se (CH₂)₉ CH=CH₂PtCl₂ reveal C=C double-bond in Fe(C₅H₄Se (CH₂)₉CH=CH₂)₂ Pt Cl₂ is free because of binding with Pt(II). The results obtained from^H,¹³C and⁷⁷Se NMR indicate that invertomers ofmeso anddl species existence. The ratio ofmeso/dl for BUnSeF Pt is ca 70/30, whereas four and three invertomers for BUnSeF Pt and BBSeFPd have been clearly observed from¹H NMR spectra. Tian Bingshou: born in Feb. 1938, Associate professor     

Convergence in the<Emphasis Type="Italic">r</Emphasis>-th mean and the Marcinkiewicz type weak law of large numbers for weighted sums of<Emphasis Type="Italic">L</Emphasis><Subscript>q</Subscript>-mixingale arrays

L _r convergence and convergence in probability for weighted sums ofL _q-mixingale arrays have been discussed and the Marcinkiewicz type weak law of large numbers forL _q-mixingale arrays has been obtained. Foundation item: Supported by the National Natural Science Foundation of China (10071058) Biography: Gan Shi-xin (1939-), male, Professor, research direction; martingale theory, probability limiting theory and Banach space geometry theory.     

重组脂肪酶自诱导发酵培养基优化

【目的】优化自动诱导发酵培养基,提高脂肪酶产量。【方法】通过对构建的一株转座子整合型脂肪酶重组菌株,采用自动诱导发酵表达方法,并结合CCD响应面实验设计方法,对自动诱导培养基中的碳源进行优化,获得了1个二次模型用于描述发酵培养基中碳源对产脂肪酶的影响。【结果】优化后的最适自动诱导培养基(W/V)组成为glycerol 2.596,glucose 0.035,lactose 1.289,tryptone 1.0,yeast extract 0.5,Na_2HPO_4·12H_2O 1.79,KH_2PO_4 0.68,NH_4Cl 0.267 5,Na_2SO_4 0.071,MgSO_4·7H_2O 0.05。【结论】发酵试验表明,最优碳源培养基的比活力为R_1=6.35U/mg,比初始发酵培养基提高近3倍。     

阿霉素负载的Fe5C2纳米粒子在光热治疗/化疗中的研究

采用高温热解法制备了粒径均一的Fe_5C_2磁性纳米粒子,并在其表面包裹磷脂改善纳米粒子的水溶性和稳定性,同时在纳米粒子表面负载阿霉素(DOX)实现化疗作用.阿霉素负载的Fe_5C_2磁性纳米粒子(Fe_5C_2-DOX-DSPE-m PEG),不仅具有一定的磁学性质,且具有优良的光热转化效率.细胞实验说明该纳米粒子对肿瘤细胞具有光热治疗和化疗协同治疗作用.