改性硅藻土负载亚铁氰化铜复合物的制备及其对Cs+的吸附性能

采用水热法、以氯化铝为铝源对硅藻土(De)进行改性,通过浸渍法将亚铁氰化铜(KCuHCF)纳米颗粒负载于改性De表面,制备出γ-AlOOH/De-KCuHCF和γ-Al₂O₃/De-KCuHCF两种复合吸附剂,对所制备的吸附剂进行了表征,并研究了其对Cs⁺的吸附性能。结果表明,所制备吸附剂具有优异的Cs⁺吸附性能,γ-AlOOH/De-KCuHCF和γ-Al₂O₃/De-KCuHCF最高吸附容量分别可达75.44、84.02 mg·g^-1,γ-Al₂O₃/De-KCuHCF对模拟卤水中Cs⁺的吸附率高达97.55%;以3 mol·L^-1 NH₄NO₃为脱附剂,经3级连续脱附后,γ-Al₂O₃/De-KCuHCF的Cs⁺脱附率可达81.88%,经过5次吸附-脱附循环后仍保持了较高的吸附量。     

基于H3PW12O40·xH2O和3，5-二氨基-1，2，4-三氮唑的POMOF的合成、表征及催化氧化碘离子性能

采用水热法合成了一例结构新颖且罕见的Keggin型多金属氧酸盐基金属有机骨架化合物,即[Cu₄（3,5-datrz）₄][PW^Ⅵ₉W^Ⅴ₃O₃₉]·H₂O （1）,其中3,5-datrz=3,5-二氨基-1,2,4-三氮唑,并通过单晶X射线衍射、傅里叶变换红外光谱、热重分析、粉末X射线衍射和元素分析进行了表征。单晶X射线衍射分析表明：化合物1属于单斜晶系,空间群为C2/c,不对称结构包含2个Cu⁺、2个3,5-datrz配体、0.5个Keggin型磷钨酸阴离子和1个水分子,除结晶水外各组分之间通过共价键连接成Keggin型多金属氧酸盐基金属有机骨架化合物。以化合物1为非均相催化剂,在温度为55℃时催化H₂O₂氧化碘离子反应。结果表明,1催化下的碘单质生成速率为6.11×10^-7 mol·L^-1·s^-1,且重复使用次数达到6次时转化率仍能高达99.6%。     

K+掺杂双钙钛矿Cs2AgInCl6的发光性质

采用固相球磨法制备了K⁺掺杂双钙钛矿Cs₂AgInCl₆纳米材料,该方法无需配体辅助,绿色环保。通过X射线衍射谱和拉曼光谱对晶体结构进行研究,通过激发光谱、发射光谱和时间分辨光谱对其发光性能进行研究。结果表明,Cs₂AgInCl₆为立方晶体,属于Fm3m空间群,由于宇称禁戒跃迁,其荧光量子产率(PLQY)低,小于0.1%。低于60%的K⁺掺杂主要取代Ag⁺的位置,引起Cs₂AgInCl₆的晶格膨胀,消除了晶格结构的反演对称性,打破了宇称禁戒跃迁,掺杂后Cs₂AgInCl₆的光致发光强度显著增强。K⁺的最佳掺杂比例为40%,Cs₂Ag_0.6K_0.4InCl₆发出中心波长为640 nm,半高宽为180 nm,平均荧光寿命达到29.2 ns,PLQY达到10.5%。当K⁺掺杂比例超过60%,K⁺开始取代Cs⁺的位置,产物发生相变,出现立方相的Cs_2-xK_1+x-yAg_yInCl₆和单斜相的Cs_2-xK_1+xInCl₆产物,这些产物由于强电子-声子耦合,非辐射复合占据主导地位。     

WQD-1沸石离子交换性能的研究

测定了W_QD-1沸石在一价碱金属离子混合溶液中的分配系数、饱和交换量和在25℃时，NH⁺₄/K⁺、NH⁺₄/Na⁺交换等温线。得出该沸石一价离子选择性序列为：Cs⁺>Rb⁺>K⁺>Na⁺>Li⁺, Na⁺/K⁺交换自由焓变ΔG(T,P)=-6.745 KJ/mol。     

3，5-二硝基水杨酸铈的制备﹑热分解机理及非等温反应动力学

用3,5-二硝基水杨酸和硝酸铈为原料,制备了3,5-二硝基水杨酸铈(CeDNS),采用元素分析、X射线荧光光谱和FTIR对其进行了表征。用TG和DSC以及变温固相原位反应池/傅立叶变换红外光谱(RS-FTIR)联用技术研究了3,5-二硝基水杨酸铈的热分解机理,对主放热反应的DSC峰进行了数学处理,计算得到了动力学参数和动力学方程。结果表明,3,5-二硝基水杨酸铈的分解反应共有3个阶段,其中包括一个脱水吸热过程和一个主放热过程,主分解反应发生在第2阶段,主分解反应的表观活化能E_a与指前因子A分别为：159.17 kJ·mol^-1 和10^11.33 s^-1,主分解阶段的反应机理服从Avrami-Erofeev方程(n=1/4),主分解反应的动力学方程为：dα/dt=10^11.33×4(1-α)[-ln(1-α)]^3/4e^-1.92×104/T。     

5-硝基-2H-四唑的合成、反应性及产物晶体结构的研究

5-氨基四唑(1)经过重氮化反应得到5-硝基四唑(5), 5与甲醛反应得到2-羟甲基-5-硝基四唑(6), 6与HCl或HBr反应分别得到5-5氯代四唑(7)和5-溴代四唑(8), 采用MS, IR, ¹H NMR, ¹³C NMR等技术对这些化合物进行了表征. 用X射线单晶衍射法测定了化合物5-硝基四唑钠(4), 5和6的晶体结构. 化合物4属于三斜晶系, P-1空间群; 化合物 5和6均属于单斜晶系, P2₁空间群, 化合物6的晶胞参数a＝0.66131(18) nm, b＝0.54905(15) nm, c＝0.7566(2) nm, Z＝2, V＝0.27470(13) nm³, D_c＝1.754 g/cm³, F(000)＝128, μ＝0.160 mm^－1.     

γ-AlOOH/Al2O3修饰硅藻土的制备与Cs+、Pb2+吸附性能

以结晶氯化铝(AlCl₃·6H₂O)作为铝源,十二烷基苯磺酸钠(SDBS)为模板剂,采用水热法在硅藻土盘上制备了束状纳米结构γ-AlOOH/Al₂O₃复合吸附剂。采用XRD、SEM、TEM、TG/DSC、N₂吸脱附等对样品进行了表征。研究了样品对¹³³Cs⁺及Pb²⁺的吸附能力。研究表明,样品γ-AlOOH/硅藻土、γ-Al₂O₃/硅藻土,对Cs⁺及Pb²⁺均具有良好的吸附性能,两者对Cs⁺的去除率分别为98.9%和99.6%;对Pb²⁺的最大吸附量分别为357.1、416.7 mg·g^-1。两种样品对Pb²⁺的吸附均符合Langmuir吸附模型。     

基于H3PW12O40·xH2O和3，5-二氨基-1，2，4-三氮唑的POMOF的合成、表征及催化氧化碘离子性能

采用水热法合成了一例结构新颖且罕见的Keggin型多金属氧酸盐基金属有机骨架化合物，即[Cu₄(3，5 - dtrz)₄][PW^Ⅵ₉W^Ⅴ₃O₃₉]·H₂O (1)，其中3，5-dtrz=3，5-二氨基-1，2，4-三氮唑，并通过单晶X射线衍射、傅里叶变换红外光谱、热重分析、粉末X射线衍射和元素分析进行了表征。单晶X射线衍射分析表明：化合物1属于单斜晶系，空间群为C2/c，不对称结构包含2个Cu⁺、2个3，5-datrz配体、0.5个Keggin型磷钨酸阴离子和1个水分子，除结晶水外各组分之间通过共价键连接成Keggin型多金属氧酸盐基金属有机骨架化合物。以化合物1为非均相催化剂，在温度为55℃时催化H₂O₂氧化碘离子反应。结果表明，1催化下的碘单质生成速率为6.11×10^-7 mol·L-1·s^-1，且重复使用次数达到6次时转化率仍能高达99.6%。     

YS+(1Σ+, 3Φ)与COS气相反应: YS++COS→YS2++CO的理论研究

采用密度泛函B3LYP方法研究了硫化钇离子YS⁺ (¹Σ⁺, ³Φ)与硫转移试剂COS在气相中的反应: YS⁺+COS→YS₂⁺+CO. 在单重基态和三重激发态势能面上都找到了四条反应通道. 但是除一条反应通道之外, 其他的反应机理和几何结构变化趋势在不同的势能面上有很大不同. 实验中生成YS₂⁺ 所表现出的吸热特征来自于在基态反应中的三条通道(A, B和C), 其活化势垒分别为28.3, 140.5和120.2 kJ·mol^-1. 计算结果表明硫转移反应没有双态反应活性, 因此产物YS₂⁺ 在低能量区的放热特征是由于基态反应物中还混有残留的激发态YS⁺.     

阳离子(从有机铵到无机阳离子)对fac-[Fe(CO)3I3]-阴离子的稳定性和毒性的调节

通过无机碘盐(MI_n)与 cis-[Fe(CO)₄I₂]反应制备了 5 个盐类化合物 fac-M[Fe(CO)₃I₃]_n (Mⁿ⁺=Na⁺ (1),K⁺ (2),Mg²⁺ (3),Ca²⁺ (4),NH₄⁺ (5)),探讨了阳离子Mⁿ⁺对fac-[Fe(CO)₃I₃]^-阴离子的稳定性和细胞毒性的影响。通过傅里叶变换红外光谱(FTIR)监测,发现盐 1~5在 DMSO、D₂O、生理盐水等介质中均能缓释 CO,其释放动力学符合一级反应动力学模型;还发现溶液中碘离子的浓度和酸度对该阴离子的缓释CO性能也具有调节作用。通过噻唑蓝(MTT)实验评估了盐1~5对膀胱癌细胞的毒性,其24 h半抑制浓度(IC₅₀)在 25~43 μmol·L^-1。与有机铵阳离子类的盐化合物相比,盐1~5在含水介质中的释放 CO速率下降,毒性亦有下调。研究还发现这类fac-[Fe(CO)₃I₃]^-阴离子在缓释CO的同时释放碘自由基,并能导致线粒体活性氧(ROS)水平、Parkin蛋白表达均上调。铁死亡抑制剂(Ferrostatin-1和Liproxstatin-1)试验结果表明这类化合物可能引发铁死亡通路并促进肿瘤细胞死亡。     

Syntheses and crystal structures of three cesium salts: Cesium 5-sulfosalicylate, cesium 3,5-dinitrosalicylate and cesium 2,4-dinitrophenoxide monohydrate

In an attempt to probe a potential template role of the large alkali-metal cation cesium in organization of biorelevant ligands, 5-sulfosalicylate, 3,5-dinitrosalicylate and 2,4-dinitrophenol complexes of cesium were prepared and structurally investigated. The structures of cesium 5-sulfosalicylate, cesium 3,5-dinitrosalicylate and cesium 2,4-dinitrophenoxide monohydrate have been determined through X-ray diffraction analysis. The 5-sulfosalicylate anion has lost the proton at the −SO₃H group while the 3,5-dinitrosalicylate anion at −COOH group but both retains the usual intermolecular hydrogen bond between phenolic and carboxylic oxygen. In cesium 2,4-dinitrophenoxide monohydrate, the Cs⁺ cation is 12-coordinate by O atoms in anions and water molecules while the metal atoms in cesium 5-sulfosalicylate and cesium 3,5-dinitrosalicylate have coordination numbers 10 and 11, respectively, with an irregular coordination sphere made up exclusively of oxygen atoms. Even more in cesium 2,4-dinitrophenoxide monohydrate, the water molecules are in rare triply bridging positions between these cations. Both complexes have layer structures containing the cations and polar groups of the ligands in core domains sandwiched by the aromatic rings above and below. The organization of all layer structures appears to be governed mainly by steric effects and electrostatic forces with very little directional influence of the cations.     

Trifluoromethanesulfonamide derivatives of azoles

Trifluoromethanesulfonamide-substituted azoles were synthesized by the reaction of 5-aminotetrazole, 3-amino-1,2,4-triazole and 3,5-diamine-1,2,4-triazole with trifluoromethanesulfonyl fluoride to prepare only monosubstituted compounds. All the compounds were fully characterized using (¹H, ¹⁹F, ¹³C) NMR spectroscopy, mass spectrometry (MS), and elemental analysis.     

Synthesis,Complexation and Photophysics of 1,3-alternate Calix[4]arene-crowns-6 Bearing Fluorophoric Units on the Bridge

Abstract

Three new calix[4]arene-crown-6 derivatives bearing a fluorophoric unit on the ether bridge were synthesized. All these compounds complex alkali metal picrates in chloroform, and the naphthocrown (2) shows the highest efficiency for cesium ion binding among the calix-crown-6 known so far. Cesium over sodium selectivity is remarkably higher in acetonitrile than in chloroform solution. ¹H NMR studies, carried out in CDCl₃ on the cesium picrate complex of ligand 2, show that the anion is involved in a π-π stacking with the naphthyl unit The lariat calix[4]-crown-6 (4) does not show any relevant change in absorption and fluorescence spectra upon cesium binding, thus indicating that the dansyl unit is not perturbed by metal ion complexation. On the contrary, for ligands 2 and 3 a luminescence intensity decrease is observed upon cation binding, which allows an easy detection of cesium even at very low concentrations (10^?7M).     

人红细胞摄入Cd2+离子的动力学和机理

不同Cd²⁺离子浓度引起的人红细胞相对溶血率及临界溶血浓度CH⁰已经测定,CH⁰=2.5×10^-4mol·L^-1。Cd²⁺跨膜进入人红细胞遵从一级动力学过程,其一级速率常数为1.2×10^-2h^-1。阴离子通道抑制剂DIDS及K⁺,Na⁺-ATPase抑制剂均可部分抑制人红细胞摄入Cd相似文献   

Investigation of cesium uptake from aqueous solutions using new titanium phosphates ion-exchangers

The uptake of cesium from aqueous solutions (pH 5) using titanium phosphates was investigated in the absence and presence of background electrolyte (0.1 M NaNO₃) using a batch technique. The determination of cesium was performed by gamma spectroscopy using ¹³⁷Cs as tracer. The obtained sorption isotherms could be satisfactorily reproduced by a Langmuir sorption equation. The maximum uptake capacity values (q _max) calculated fitting the experimental data by this equation were 167 and 118 mg/g for solutions of initial pH 5 in the absence and presence of background electrolyte. Kinetics data obtained at 293, 308 and 323 K could satisfactorily reproduced by the pseudo-second order equation. It was demonstrated that the new synthesized materials can remove considerable amounts of cesium from aqueous solutions and ion exchange is considered to be the principal mechanism for cesium removal. Toxicity characteristic leaching procedure and desorption tests provided data about the application of the sorbents in environmental remediation.     

Solvent effect in the kinetics of cobaloxime(II)-catalyzed oxidative dehydrogenation of 3,5-di-tert-butylcatechol by O2

In the presence of triphenylphosphinecobaloxime(II), 3,5-di-tert-butylcatechol undergoes catalytic oxidative dehydrogenation to the corresponding 1,2-benzoquinone (DTBQ) at room temperature and atmospheric dioxygen pressure. The semiquinone anion radical (DBS^•−) and its cobaloxime(III), complex Co^III(DBSQ)^•−) have been detected as intermediates by ESR spectroscopy. The kinetics were followed in benzene by measuring the dioxygen uptake as a function of time. The reaction is somewhat faster in MeOH, which is due to the greater stability of the hydrogen-bonded intermediate (X) formed from superoxocobaloxime (Co^IIIO₂) and the catechol. H-atom abstraction occurs in the rate-determining decomposition of X. The system investigated is a functional model of catecholase (oxidase) activity, based on free-radical intermediates, a possibility recently demonstrated for certain oxidoreductases.     

Specific Uphill Transport of Zinc as Zn(SCN)42− Ion using Na+-Dicyclohexyl-18-Crown-6 as Carrier

Sodium-dicyclohexyl- 18-crown-6 complex cation was used as carrier for the uphill transport of zinc as Zn(SCN)₄^2? complex anion. By using L-cysteine as a metal ion acceptor in the receiving phase at the optimized pH of 7.6, the amount of zinc transport through the liquid membrane after 90 min was 97.2 ± 1.0%. The selectivity and efficiency of zinc transport from aqueous solutions containing equimolar mixtures of Ag⁺, Cd²⁺ Co²⁺, Cu²⁺, Fe²⁺, Ni²⁺, Pb²⁺, Pd²⁺, Sr²⁺, Bi³⁺, Cr³⁺ and Fe³⁺ ions was investigated. In the presence of NH₂OH.HCl as a suitable masking agent in the source phase, the interfering effect of Cu²⁺ and Pb²⁺ ions was diminished drastically.     

Synthesis and crystal structures of 3D supramolecular compounds: [ M (4,4′-bipy)2(H2O)4] · (4,4′-bipy)2 · (3,5-daba)2 · 8H2O ( M =Zn,Mn)

Two new supramolecular compounds [M(4,4′-bipy)₂ (H₂O)₄] ·?(4,4′-bipy)₂ ·?(3,5-daba)₂ ·?8H₂O (M=Zn(1) or Mn(2), 4,4′-bipy =?4,4′-bipyridine, 3,5-daba =?3,5-diaminobenzoic acid anion) were synthesized and characterized by elemental analysis and X-ray crystal diffraction. In [M(4,4′-bipy)₂(H₂O)₄]²⁺, the M(II) is coordinated by two nitrogen atoms from two 4,4′-bipy molecules and four oxygen atoms from four waters to form an octahedral configuration. There exist uncoordinated 4,4′-bipy molecules, 3,5-diaminobenzolate counterions and water guests in the compounds. The 3D structures of the title supramolecular compounds are constructed by rich hydrogen bonds among [M(4,4′-bipy)₂(H₂O)₄]²⁺, uncoordinated 4,4′-bipy molecules, water molecules and 3,5-daba, containing a diverting hexa-member water ring.     

Cesium Platinide Hydride 4Cs2Pt⋅CsH: An Intermetallic Double Salt Featuring Metal Anions

With Cs₉Pt₄H a new representative of ionic compounds featuring metal anions can be added to this rare‐membered family. Cs₉Pt₄H exhibits a complex crystal structure containing Cs⁺ cations, Pt^2? and H^? anions. Being a red, transparent compound its band gap is in the visible range of the electromagnetic spectrum and the ionic type of bonding is confirmed by quantum chemical calculations. This cesium platinide hydride can formally be considered as a double salt of the “alloy” cesium–platinum, or better cesium platinide, Cs₂Pt, and the salt cesium hydride CsH according to Cs₉Pt₄H≡4 Cs₂Pt?CsH.     

Reactivity of bis(pyrazol-1-yl)methanes functionalized by 2-hydroxyphenyl and 2-methoxyphenyl on the methine carbon atom with W(CO)5THF

Reactions of 2-hydroxyphenyl and 2-methoxyphenylbis(pyrazol-1-yl)methanes as well as 2-hydroxyphenyl and 2-methoxyphenylbis(3,5-dimethylpyrazol-1-yl)methanes with W(CO)₅THF have been carried out. Heating 2-hydroxyphenylbis(pyrazol-1-yl)methane (L¹) with W(CO)₅THF in THF at reflux yielded complex (L¹)W(CO)₄.L¹, while similar reaction of 2-hydroxyphenylbis(3,5-dimethylpyrazol-1-yl)methane (L²) with W(CO)₅THF resulted in the cleavage of a C_sp3-N bond to generate 1,2-bis(2-hydroxyphenyl)-1,2-bis(3,5-dimethylpyrazol-1-yl)ethane (L) and pyrazole derivative W(CO)₅(3,5-Me₂PzH) (Pz = pyrazol-1-yl). These two fragments were connected together through strong O…H-N and O-H…N hydrogen bonds to form complex L.[W(CO)₅(3,5-Me₂PzH)]₂. The analogous results were observed in the treatment of 2-methoxyphenylbis(pyrazol-1-yl)methane (L³) with W(CO)₅THF, which gave product L′.[W(CO)₅(PzH)]₂ (L′ = 1,2-bis(2-methoxyphenyl)-1,2-bis(pyrazol-1-yl)ethane) as well as certain amount of complex (L³)W(CO)₄. In addition, during the reaction of 2-methoxyphenylbis(3,5-dimethylpyrazol-1-yl)methane (L⁴) with W(CO)₅THF, partial decomposition reactions took place to yield complexes (L⁴)W(CO)₄ and W(CO)₅(3,5-Me₂PzH), but no hydrogen bond was found between these two moieties.