Tetraethylenepentamine-functionalized magnetic mesoporous composites as a novel adsorbent for the removal Cr(Ⅲ)-ethylenediaminetetraacetic acid in complex solution

A novel tetraethylenepentamine(TEPA) functionalized magnetic mesoporous silica adsorbent(FNMs/TEPA) was prepared for the adsorption of Cr(Ⅲ)-ethylenediaminetetraacetic acid(EDTA)from wastewater. The characterization of the prepared adsorbent certified that TEPA was modified onto the magnetic mesoporous silicon(FNMs), while FNMs/TEPA maintained the ordered mesoporous and pristine magnetic properties. The batch adsorption experiments demonstrated that TEPA significantly enhanced the removal capacity of the adsorbent for Cr(Ⅲ)-EDTA. FNMs/TEPA exhibited an excellent adsorption property(13.84 mg·g-1) at p H 4.0. Even in the presence of high concentrations of coexisting ions and organic acids, the adsorption performance of FNMs/TEPA was stable. Experimental characterization and DFT demonstrated that the adsorption of Cr(Ⅲ)-EDTA was ascribed to the electrostatic interaction, hydrogen bonding, and complexation between Cr(Ⅲ)-EDTA and amino groups on the adsorbent surface. The analysis of the independent gradient model(IGM) shows that electrostatic interaction is the main mode of action in the adsorption process. Moreover, FNMs/TEPA demonstrated remarkable reusability in three regeneration cycles. These findings indicated that FNMs/TEPA possessed excellent application prospects in the disposal of wastewater containing Cr(Ⅲ)-EDTA.

基于静电和金属络合协同作用的MIL-101(Cr)-NH_(2)高效吸附水中单宁酸

通过水热法制备了一种氨基改性的MIL-101(Cr),采用静态吸附法研究了MIL-101(Cr)-NH_(2)对废水中单宁酸的吸附性能。采用X射线衍射仪(XRD)、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)和氮气吸附法表征了材料的结构和形貌,研究了pH值、吸附时间、初始浓度及离子强度对其单宁酸吸附性能的影响,探究了其对单宁酸的吸附机理。随着溶液pH增大,MIL-101(Cr)-NH_(2)对单宁酸的吸附量逐渐升高,最佳pH为7.0。MIL-101(Cr)-NH_(2)对单宁酸的吸附过程符合拟二级动力学模型、Freundlich模型和Temkin模型,说明吸附过程为多层化学吸附。扩散模型拟合结果表明,膜扩散和粒子内扩散同时控制吸附过程。在T=303 K、pH=7时,MIL-101(Cr)-NH_(2)饱和吸附量高达2031 mg/g。通过Zeta电位和FTIR等表征分析发现,单宁酸主要靠静电作用和金属络合作用被吸附在MIL-101(Cr)-NH_(2)上。

CRYSTAL STRUCTURE OF A 2D SHEET－LIKE μ－CYANIDO－OXAMIDATO BRIDGED Fe（III）－Cu（II） HETERNUCLEAR COMPLEX

The synthesis is and crystal structure are reported for the sheet-like compourd [CU2(oxpn)Fe(CN )5(NO)]. there oxpn is the dianion of M, M'-bis(3-aminopropyl)oxamide. This compound crustallizes in the orthogonal space group Puma. with a=11 .413(4), b=22.242(5), c=7.736(2) A, and Z=4.The structure was refined to conventionat discrepancy factors R=0.047 and Pw=0.054. The Cu(II ) and Fe(III)centers are bridged by oxpn and cyanide, the formal behaves as a his-terdentate tigand bound to cooper(II)ion to form (II) dimers. whereas the latter bridges Cu(II) and Fe(III) centers in both symmetric and asymetric end- to-end bis-monodentate fashions, spreading out along be plane to form a 20 network. The Structure is made up of CuFe unit with Cu(II) and Fe(III) ions locating in a distorted square-based pyramid and a compressed octahedron, respectively.

Cr(III)在钝顶螺旋藻中的生物富集及其对钝顶螺旋藻生长的影响

本实验研究了钝顶螺旋藻对Cr(III)的吸收和生物转化以及Cr(III)对钝顶螺旋藻的生长影响,用ICP-MS-HPLC对无机Cr(III)经钝顶螺旋藻吸收后的存在价态进行了分析。结果表明,钝顶螺旋藻对Cr(III)具有良好的富集和生物转化能力,在本实验中总铬富集量可达到173.17mg/g,有机化程度可高达96.99%。ICP-MS-HPLC分析结果表明没有有毒的Cr(VI)的产生。此外,干重测定结果显示低浓度的Cr(III)(<234.38×10-6g/g)促进钝顶螺旋藻的生长,高浓度的Gr(Ⅲ)(>234.38×10-6g/g)则抑制共生长,并导致钝顶螺旋藻形态异常。在一定范围内钝顶螺旋藻能高效富集Cr(III),可作为安全营养的保健食品;钝顶螺旋藻抗高Cr(III)压,吸附高浓度Cr(III)的能力使其可用于环境中Cr(III)污染的去除。

Effect of shaking time, ionic strength, temperature and pH value on desorption of Cr(III) adsorbed onto GMZ bentonite

The Cr（III） desorption experiments of Gaomiaozi （GMZ） bentonite in aqueous solutions were performed. The variables affecting the desorption behaviors, such as contact time, concentration of the desorbent, pH value of the solution, temperature and desorption isotherms, were investigated by the batch experiments. The results show that the adsorbed Cr（III） on GMZ bentonite can be easily extracted by the desorbent. Kinetics examination shows that desorption is slower than adsorption, and the desorption rate increases with time and reaches the equilibrium after 3 h. The final desorption ratios of Cr（III） are 89.4%, 56.5%and 77.2%in the desorption solution with 0.1 mol/L HCl, 1 mol/L NaCl, and 1 mol/L CaCl2, respectively, and the concentration can promote the desorption progress. Furthermore, the results of successive regeneration cycles indicate that the bentonite has a good regeneration ability and reusability. The pH value is an important factor in the Cr（III） desorption from the GMZ bentonite. The results of adsorption and desorption isotherms show that both adsorption and desorption isotherms are consistent with the Freundlich equation. The comparison of adsorption and desorption isotherms implies that the adsorption/desorption hysteresis is negligible and the transport of Cr（III） in bentonite can be described by a reversible adsorption process.

Syntheses,Crystal Structures and Antibacterial Activities of Complexes [(C_9H_(18)NS_2)_3M(Ⅲ)](M = Sb and Bi)

Two novel complexes,[（C9H18NS2）3Sb（III）]（1） and [（C9H18NS2）3Bi（III）]（2）,were synthesized and characterized by elemental analysis,IR,TG and X-ray single-crystal diffraction.Both 1 and 2 crystallize in the monoclinic system,P21/c space group.The data for 1：a = 1.6964（3）,b = 1.02149（17）,c = 2.5650（3） nm,β = 121.824（8）°,Z = 4,V = 3.7766（10） nm^3,Dc = 1.293 g·cm^-3,F（000） = 1536,μ = 1.082 mm^-1,the final R = 0.0500,wR = 0.1562 and S =1.072.The data for 2：a = 1.6802（9）,b = 1.0256（6）,c = 2.5083（10） nm,β = 121.77（3）°,Z = 4,V = 3.675（3） nm^3,Dc = 1.486 g·cm^-3,F（000） = 1664,μ = 5.159 mm^-1,the final R = 0.0481,wR = 0.1055 and S =1.076.The coordinated geometry of the central M（III） with six sulfur atoms from three ligands is a distorted pentagonal pyramid configuration.The dimer structural system is formed by the weak interactions of M…S and C-H…S between two molecules.The complexes were valued for their antibacterial activities by agar-streak method.It was found that 1 is active against the four test bacterial organisms.

The Aggregates in LB Films of Schiff base Aluminium (III) Complex

The surface pressure-area (pi -A) isotherm of Schiff base aluminium (III), tris (2-hydroxy-5-nitro-N-dodecyl-benzylideneaminato) aluminium (III) (denoted as Al(TAl2)(3)), on pure water subphase was investigated. The molecular area, 0.48 nm(2), is one-third of expected value that indicated the aggregation took place. The Langmuir-Blodgett (LB) films of Al(TAl2), was transferred and characterized. The AFM image confirmed the formation of aggregates.

Co(II)-salen complex encapsulated into MIL-100(Cr) for electrocatalytic reduction of oxygen

Co（Ⅱ）-salen was encapsulated in MIL- 100（Cr） metal organic framework by ＂ship in a bottle＂ to synthesize a new electrocatalyst, Cosalen@MIL- 100（Cr）. The material was characterized by XRD, FT-IR, UV-Vis and N2-adsorption. The Cosalen@MIL-100（Cr） modified glassy carbon electrode exhibits a well-defined reduction peak at the potential of -0.21 V toward the oxygen reduction reaction （ORR） by cyclic voltam- metry （CV） in pH = 6.84 phosphate buffer. Almost 400 mV positive shift of potential at Cosalen@MIL-100（Cr） modified electrode for ORR compared with that at bare glassy carbon, indicates that Cosalen@MIL-100（Cr） possesses excellent electrocatalytic activity. The transferred number of electrons for ORR was determined by chronocoulometry. The result suggests that the introduction of Co（II）-salen complex into MOF increases the electrocatalytic activity via a four-electron reduction pathway. Furthermore, this electrocatalyst exhibits good stability and reproducibility.

Synthesis,Crystal Structure and Fluorescent Property of a Lanthanum(Ⅲ) Complex Coordinated with Quinolinyloxy Acetamide Ligand

A novel lanthanum（III） complex, [LaL2（NO3）3].H2O （1） based on L （L = N-（na- phthalene-l-yl）-2-（quinolin-8-yloxy）acetamide）, was synthesized and characterized by X-ray diffraction. The crystal of I belongs to the monoclinic system, space group C2c with Mr= 1017.69, a = 25.1438（17）, b = 13.5950（9）, c = 18.2349（12） A, β= 132.4980（10）° V= 4595.8（5） A3, Z= 4, Dc = 1.471 Mg/m3, F（000） = 2056,μ= 1.004 mm-1, R = 0,0588 and wR = 0.1402. The central La（lI1） ion is coordinated to four oxygen atoms, two nitrogen atoms from two independent acetarnide ligands and six oxygen atoms from three nitrate anions, possessing a distorted icosahedron coordination geometry. In the crystal of 1, intermolecular N-H……O hydrogen bonds linked the molecules into chains along the c axis. In solid state and CH3CN solution, complex 1 exhibits stronger fluorescent emission than the ligand L.

The Complex Magnetism in the Breathing Pyrochlore LiIn(Cr_(1-x)Rh_x)_4O_8

We perform a detailed investigation of the new ＇breathing＇ pyrochlore compound LiInCr4O8 through Rh substi- tution with measurements of magnetic susceptibility, specific heat, and x-ray powder diffraction. The antiferro- magnetic phase of LiInCr4O8 is found to be slowly suppressed with increasing Rh, up to the critical concentration of x = 0.1 where the antiferromagnetic phase is still observed with the peak in specific heat Tp = 12.5 K, slightly lower than Tp =14.3 K for the x = 0 compound. From tile measurements of magnetization we also uncover evidence that substitution increases the amount of frustration. Comparisons are made with the LiGayIn1-yCr4O8 system as well as other frustrated pyrochlore-related materials and comparable amounts of frustration are found. The results of this work show that the engineered breathing pyrochlores present an important method to further understand the complex magnetism in frustrated systems.

Synthesis, Characterization and X-Ray Structure of a Ba(II)/Ag(I)/Cr(III)-Oxalate Salt with Water-Filled Nanochannels

A novel mixed barium(II)/silver(I)/chromium(III) oxalate salt, Ba0.5Ag2[Cr(C2O4)3]·5H2O (1), with open architecture has been synthesized in water and characterized by elemental analysis, vibrational and electronic spectra, and single crystal X-ray structure determination. Compound 1 crystallizes in a monoclinic space group C2/c, with unit cell parameters a = 18.179(3), b = 14.743(2), c = 12.278(2)Å, β = 113.821(3), V = 3010.34(90) Å3, Z = 8. The structure is characterized by a network of anionic [Cr(C2O4)3]3- units connected through the O atoms of the oxalates to Ba2+ and Ag+ sites, forming a three-dimensional coordination polymer with one-dimensional isolated nanochannels parallel to the c axis, and encapsulating hydrogen-bonded guest water molecules. The bulk structure is consolidated by O–H···O bridgings within the nanochannels and by coulombic interactions.

Crystal Structures and Photoluminescence Properties of Two Lanthanide Complexes Constructed by Flexible 1,2-Phenylenediacetic Ligand

Two 3D Ln-organic coordination frameworks（Ln = Pr3＋ for 1 and Er3＋ for 2） have been constructed. Single-crystal X-ray diffraction analysis reveals that the two complexes have similar structures and belong to the monoclinic C2/c space group. The trans-μ4-（η2：η1）-（η1：η1） 1,2-pda2- anions link the LnIII centers to generate a 2D network containing helical motif. The dimensionality is extended into a 3D architecture through cis-bis（μ2-η2：η1） 1,2-pda2- anions linking. The geometry of Ln3＋ ions is single-capped anti-square prism. Two complexes were characterized by IR spectra and thermogravimetric analysis. The solid fluorescence of 1 and 2 was also investigated at room temperature.

Synthesis and Crystal Structure of a Di-μ_2-phenolic Bridged Binuclear Manganese(Ⅲ) Schiff Base Complex

A new complex [Mn（L）（NCS）]2·0.5CH3CN （H2L = N,N＇-bis（chlorosalicylidene）-1,2-diaminoethane） has been synthesized,and its structure （C70H51Cl8Mn4N13O8S4,Mr = 1833.84） was determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system,space group C2/c with a = 25.883（2）,b = 12.3320（13）,c = 13.5951（16） ,β = 112.906（2）,V = 3997.2（7） 3,Z = 2,Dc = 1.524 g/cm3,μ（MoKα） = 1.050mm-1,F（000） = 1852,S = 1.098,the final R = 0.0630 and wR = 0.1847 for 2542 reflections with Ⅰ 〉 2σ（Ⅰ）. The centrosymmetric title complex contains a dimer in which two distorted octahedral Mn（Ⅲ） centers are bridged equatorially by phenolic oxygen of the Schiff base ligand. The units of the complex are linked via weak C-H···N hydrogen bonds,leading to the formation of 1D chains along the b axis. The weak π-π packing interactions and weak intermolecular C（3）-H（3）···N（3） hydrogen bonds stabilize the crystal structure.

Syntheses, Crystal Structures and Anticancer Activities of Dithiocarbamate Bismuth(Ⅲ) Complexes

Two novel complexes, [Bi（III）（S2CNBn Et）3] 1 and [Bi（III）（S2CNPPPy-2）3] 2, were synthesized and characterized by elemental analysis, IR, ^1H NMR, ^13C NMR, TG-DTG and X-ray single-crystal diffraction. The structure reveals that complex 1 belongs to the monoclinic system, space group P21/c with a = 11.457（5）, b = 17.437（8）, c = 33.439（14）, β= 98.499（8）o, Z = 4, V = 6607（5）3, Dc = 1.689 g·cm^-3, F（000） = 3328, μ= 5.742 mm^-1, the final R = 0.0906, w R = 0.1678 and S = 1.032. The structure indicates that complex 2 belongs to the triclinic system, space group P1 with a = 12.608（9）, b = 12.622（8）, c = 12.49（6）, α = 102.652（15）, β = 103.013（14）, γ = 109.698（10）o, Z = 1, V = 1762.3（19）3, Dc = 1.741 g·cm^-3, F（000） = 916, μ = 5.395 mm^-1, the final R = 0.048 2, w R = 0.1206 and S =1.046. In the two complexes, each six-coordinated Bi（III） atom adopts a pentagonal pyramidal configuration with six sulfur atoms from three ligands, and the dimmer structures are formed by weak interactions of Bi···S between two molecules. The anticancer activities of the two complexes were studied by evaluating their cytotoxicities against several human cancer cell lines using the MTT assay. Results indicated complex 2 showed moderate cytotoxic effects on the selected cancer cells.

STUDY ON BINUCLEAR COPPER(I)COMPLEXES III.SYNTHESIS,CHARACTERIZATION AND ELECTROCHEMISTRY OF DICHLORO-TRIS(4-VINYLPYRIDINE)-DICOPPER(I)COMPLEX

Recent years,many novel complexes have been prepared by using hetero-bidentate ligands.However,complexes with such ligands as 4-vinylpyridine which has two different coordinating sites have not been reported,and only a few complexes of Cu(I)have been published^(1-3).The title complex Cu_2(C_5H_4N·CH=CH_2)_3Cl was prepared and characterized by elemental analyses,ICP,IR,and electronic spectra.Its conductivity,oxidation potential and reduction potential were measured.

Synthesis and Crystal Structure of Tris(N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinonato)iron(III)

The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration Mr=773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P31c; a=15.943(2), c=17.612(4)? V=3877.0(12)?, Z=4, Dc=1.325g/cm3, m=0.445mm-1, F(000)=1634, R=0.0446, wR= 0.1154 for 3085 reflections with I >2s(I). The bond lengths from iron to oxygens are 1.980(1)?for the ketone oxygens and 2.071(1)?for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37. The dihedral angles are 0.5(2)?between chelate ring plane and pyridine ring plane and 71.31(7)?between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)? respectively.

Synthesis, characterization, and stability of iron (III) complex ions possessing phenanthroline-based ligands

It has previously been demonstrated that phenanthroline-based ligands used to make gold metallotherapuetics have the ability to exhibit cytotoxicity when not coordinated to the metal center. In an effort to help assess the mechanism by which these ligands may cause tumor cell death, iron binding and removal experiments have been considered. The close linkage between cell proliferation and intracellular iron concentrations suggest that iron deprivation strategies may be a mechanism involved in inhibiting tumor cell growth. With the creation of iron (III) phen complexes, the iron binding abilities of three polypyridal ligands [1,10-phenanthroline (phen), 2,9-dimethyl-1, 10-phenanthroline (methylphen), and 2,9-di-sec-butyl-1, 10-phenanthroline (sec-butylphen)] can be tested via a competition reaction with a known iron chelator. Therefore, iron (III) complexes possessing all three ligands were synthesized. Initial mass spectrometric and infrared absorption data indicate that iron (III) tetrachloride complex ions with protonated phen ligands (RphenH+) were formed: [phenH][FeCl4], [methylphenH][FeCl4], [sec-butylphenH][FeCl4]. UV-vis spectroscopy was used to monitor the stability of the complex ions, and it was found that the sec-butylpheniron complex was more stable than the phen and methylphen analogues. This was based on the observation that free ligand was observed immediately upon the addition of EDTA to the [phenH][FeCl4] and [methylphenH] [FeCl4] complex ions.

龙胆紫分子印迹聚合物的制备及其对Cr(III)吸附性能的研究

本文以龙胆紫(GV)为模板分子、丙烯酸(AA)为单体、N,N’-亚甲基双丙烯酰胺(MBA)为交联剂、偶氮二异丁腈(AIBN)为引发剂,乙腈为制孔剂,采用本体聚合法制备了龙胆紫分子印迹聚合物(GV-MIP)。利用制得的分子印迹聚合物对不同浓度的Cr(III)在不同温度下的吸附量进行研究,并与空白印迹聚合物(NMIP)及Cr(III)离子印迹聚合物(Cr-MIP)进行对比,发现GV-MIP对Cr(III)的吸附量显著高于NMIP和Cr-MIP,且随着Cr(III)浓度的增大而增大,最大吸附量为126.16 mg/g,最佳吸附温度为室温25℃。

Periodate Oxidation of a Ternary Complex of Nitrilotriacetatochromium(III) Involving ß-Alanine as Co-Ligand

The kinetics of the periodate oxidation of chromium(III)-complex, [CrIII(NTA)(Ala)(H2O)]-(NTA = Nitrilotriacetate and Ala = &#223;-alanine) to Cr(VI) have been carried out for the temperature range 15°C - 35°C under pseudo-first order conditions, >>?[complex]. Reaction obeyed first order dependence with respect to and [Cr(III)], and the rate of reaction increases with increasing of pH for the range 3.40 - 4.45. Experimentally, the mechanism of this reaction is found to be consistent with the rate law in which the hydroxo species, [CrIII(NTA)(Ala)(OH)]2- is considerably much more reactive than their conjugate acid. ΔH* and ΔS* have been calculated. It is proposed that electron transfer occurs through an inner-sphere mechanism via coordination of to chromium(III).

Synthesis, Crystal Structure and Thermal Behavior of a 3-D Barium(II)/Iron(III)-Oxalate Polymer

Reaction of Ba(NO3)2 with Fe(NO3)3·9H2O and H2C2O4·2H2O in aqueous medium readily affords, in high yield, the bimetallic complex polymer of chemical composition {Ba6(H2O)17[Fe(C2O4)3]4}·7H2O (1), consistent with the expected ratio of 3BaII vs. 2FeIII. Compound 1 was fully characterized by elemental and thermal analyses, vibrational FTIR spectroscopy, and by single crystal X-ray structure determination. The bulk structure of 1 is a 3-D metal-organic framework held together by intermetallic linkages across oxalate and aqua oxygen bridgings. Thermal analyses of 1 show significant weight losses corresponding to water molecules (lattice and coordinated), followed by the decomposition of the network.