检索结果-南通市图书馆

Transactions of Nonferrous Metals Society of China 2019年第11期29卷 2400-2410页

作者： Xue-feng PENG Yang ZHANG Bing-qiang FAN Shi-li ZHENG Xiao-jian WANG Ying ZHANG Ping LI Feng-qiang LIU Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Pangang Group Co. Ltd.Panzhihua 617067China

A novel method for the separation and reclamation of vanadium and chromium from acidic solution was proposed. The principle for the separation is based on selective complexation. In specific, V(V) can be complexated by dithiocarbamate to form VO(R1R2NCS2)3 precipitate, leaving Cr(Ⅲ) remained in the acidic solution. Then the reclamation of V and Cr from VO(R1R2NCS2)3 precipitate and Cr(Ⅲ)-bearing solution can be reached by decomplexation and neutralization, respectively. The kinetics of the complexation reaction was studied. In addition, the precipitation ratio of vanadium reached 97% and the loss of chromium was less than 4% after process optimization. The complexing agent could be regenerated with a high ratio of 99.5%. The method was successfully applied to treating chromium-vanadium-bearing slag produced in conventional vanadium production industry. Vanadium and chromium could be extracted from the slag in the form of calcium vanadate and Cr2O3 product with a purity of over 98%.

关键词： vanadium chromium separation complexation dithiocarbamate

complexation of Triptycene-Derived Macrotricyclic Host with Bisparaquat Derivative and Self-Folding Guest： A Switchable Process Controlled by K＋ Ions

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2013年第5期31卷 607-611页

作者： Ying Han Jiabin Guo Jing Cao Chuanfeng Chen Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Triptycene-derived cylindrical macrotricyclic host with two dibenzo-30-crown-lO cavities could form stable 1 ： 1 complexes with not only polyether linked bisparaquat derivative but also a self-folding A-D-A guest in solu- tion and/or solid state. Moreover, it was found that switchable processes between the host and both the bisparaquat derivative and the self-folding guest could be further controlled by potassium ions.

关键词： complexation macrotricyclic host paraquat triptycene switchable

complexation between uranyl(Ⅵ)and CMPO in a hydroxyl-functionalized ionic liquid:An extraction,spectrophotography,and calorimetry study

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2022年第7期33卷 3451-3455页

作者： Baihua Chen Jun Liu Hongyuan Wei Yuchuan Yang Xingliang Li Shuming Peng Yanqiu Yang Institute of Nuclear Physics and Chemistry CAEPMianyang 621900China

The extraction complexes of uranyl(Ⅵ)in HNO_(3)to a hydroxyl-functionalized ionic liquid(IL)phase,HOEtmimNTf2bearing CMPO,were *** possibly successive extraction complexes,UO_(2)L^(2+)(L=CMPO),UO2L_(2)^(2+) and UO_(2)L_(3)^(2+),were detected based on variable U/L ***(Ⅵ)prefers to be extracted as complex UO_(2)L_(3)^(2+),combining with the ions from HOEtmimNTf_(2) to construct a solid material through *** thermodynamics of complexes,UO_(2)L_(j)^(2+)(j=1-3),were studied by spectrophotometry and *** the formation reactions are principally driven by entropy,although a small part of the driving force of complexes UO_(2)L_(2)^(2+)and UO_(2)L_(3)^(2+) comes from *** on the thermodynamic properties for complex UO_(2)L_(3)^(2+),we provide a possible coordination mode in HOEtmim NTf_(2):the first CMPO molecule coordinates with UO_(2)^(2+) in a bidentate fashion while the others do in a monodentate *** results offer a thermodynamic insight into the formation behaviors of the uranyl(Ⅵ)/CMPO complexes involving the special IL HOEtmimNTf_(2),which is of significance to advance the novel IL extraction strategy.

关键词： Uranyl(Ⅵ) CMPO Ionic liquid Solvent extraction complexation Thermodynamics

Synthesis and Spectroscopic Characterizations on the complexation of Three Different Metal Ions Ba(Ⅱ),Ni(Ⅱ),and Ce(Ⅲ)with Atenolol Drug Chelate

在线全文

学校读者我要写书评

暂无评论

光谱学与光谱分析 2020年第6期40卷 1988-1992页

作者： Samy M El-Megharbel Tariq Altalhi Abdullah Ayad Salem Alruqi Moamen S Refat Department of Chemistry Faculty of ScienceTaif UniversityAl-Haweiah21974TaifSaudi Arabia Department of Chemistry Faculty of ScienceZagazig UniversityZagazigEgypt Faculty of Medicine Umm Al Qura UniversityMekkahSaudi Arabia Department of Chemistry Faculty of SciencePort Said UniversityPort SaidEgypt

Three types of metal ions barium(Ⅱ),nickel(Ⅱ)and cerium(Ⅲ)complexity of ATN drug have been prepared and characterized using molar conductance method,FT-IR,electronic,and 1H-NMR analysis *** chemical and physical results for all atenolol complexes are agreement with the speculated *** the divalent(Ba&Ni)and trivalent(Ce)metal atenolol a molar ratio 1∶2 was *** chemical analysis showed that for the divalent metal complexes,the chloride ions are not involved in the complexes,suggesting that all of these complexes,[Ba(ATN)2]·2 H2O and[Ni(ATN)2(H2O)2]·4 H2O are ***,for the cerium(Ⅲ)complex,[Ce(ATN)2(NO3)]·3 H2O,the nitrate group is existed inside the coordination *** make astable metal complexity with barium(Ⅱ),nickel(Ⅱ)and cerium(Ⅲ)*** absorption analysis of Atenolol give two fundamental peaks at 225 nm and 274 nm refers to variation in transition electrons of ligand,UV spectral analysis of the three complexity obtained give asymmetric broad band in the range 200~400 nm,the reults are convenient with the suggestion of metal-nitrogen and metal-oxygen *** infrared analysis data proved that ATN act as bidentate ligand through the N atom of the-NH group and O atom of the deprotonated alcoholic OH ***(Ⅱ)and cerium(Ⅲ)complexity make six-coordinate geometry,whereas the barium(Ⅱ)complex exhibit four-coordinate ***(Ⅱ)-ATN complex has an effective magnetic moment equal 3.12 B.M,that is assigned to octahedral *** 1H-NMR spectral results of Ba(Ⅱ)-ATN complexity give strong signal at^4.00 ppm due to protons of-CH2 that influenced by low degree due to *** results confirm the position of chelation through the N atom of the-NH group and O atom of the deprotonated alcoholic OH group.

关键词： Atenolol drug Metal ions complexation

Unravelling the effects of complexation of transition metal ions on the hydroxylation of catechol over the whole pH region

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2022年第5期34卷 392-402页

作者： Zexiu An Jianfei Sun Qiong Mei BoWei Mingxue Li Ju Xie Maoxia He Qiao Wang Environment Research Institute Shandong UniversityQingdao 266237China School of Environmental and Materials Engineering Yantai UniversityYantai 264005China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Catechol pollutants(CATPs)serving as chelating agents could coordinate with many metal ions to form various CATPs-metal *** information is available on the effects of complexation of metal ions on CATPs *** work presents a systematical study of·OH-mediated degradation of catechol and catechol-metal complexes over the whole pH range in advanced oxidation processes(AOPs).Results show that the pH-dependent complexation of metal ions(Zn^(2+),Cu^(2+),Ti^(4+)and Fe^(3+))promotes the deprotonation of catechol under neutral and even acidic *** radical adduct formation(RAF)reactions are both thermodynamically and kinetically favorable for all dissociation and complexa-tion species,and-OH/-O-group-containing C positions are more vulnerable to·OH *** kinetic results show that the complexation of the four metal ions offers a wide pH range of effectiveness for catechol *** pH 7,the apparent rate constant(k_(app))values for different systems follow the order of catechol+Ti^(4+)≈catechol+Zn^(2+)>catechol+Cu^(2+)>catechol+Fe^(3+)>*** mechanistic and kinetic results would greatly improve our understanding of the degradation of CATPs-metal and other organics-metal complexes in *** toxicity assessment indicates that the·OH-based AOPs have the ability for decreasing the toxicity and increasing the biodegradability during the processes of catechol degradation.

关键词： Catechol Metal ions complexation pH Degradation

Recovery of Tungsten (Ⅵ) from Aqueous Solutions by complexation-ultrafiltration Process with the Help of Polyquaternium

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2012年第5期20卷 831-836页

作者：曾坚贤孙霞辉郑立锋贺勤程李书 College of Chemistry and Chemical Engineering Hunan University of Science and Technology

Polyquaternium-6 (PQ6) as the water-soluble polymer was used for complexing the anion forms of tungsten (Ⅵ) before ultrafiltration. Tungsten (Ⅵ)-PQ6 complex was retained by polysulfone hollow fiber ultrafiltration membrane in the complexation-ultrafiltration process. Effects of various operating parameters such as polymer metal ratio(PMR), pH and chloride ion concentration on permeate flux (J) and tungsten rejection coefficient (R) were investigated. The integration of four experiments including concentration, decomplexation, diafiltration and reuse of regenerated polymer was carried out. In the process of concentration, J declines slowly and R is about 1 at PMR of 3 and pH of 7. Tungsten concentration in the retentate increases linearly with volume concentration factor. Tungsten is concentrated efficiently with the membrane. The concentrated retentate was used further for the decomplexation. It takes about 6 min to reach the decomplexation equilibrium at chloride ion concentration of 50 mg·L-1 . The decomplexation percentage of tungsten (Ⅵ)-PQ6 complex reaches 56.1%. In the diafiltration process, tungsten (Ⅵ) can be extracted effectively by using 50 mg·L-1 chloride ion solution, and the purification of the regenerated PQ6 is acceptably satisfactory. The regenerated PQ6 was used to bind tungsten (Ⅵ) at various pH values. The binding capacity of the regenerated PQ6 is close to that of fresh PQ6, and the recovery percentage of binding capacity is higher than 90%.

关键词： tungsten (VI) polyquaternium-6 complexation ultrafiltration

Dish-like higher-ordered palladium nanostructures through metal ion-ligand complexation

在线全文

学校读者我要写书评

暂无评论

Nano Research 2018年第6期11卷 3442-3452页

作者： Xi Yin Miao Shi Kam Sang Kwok Haidong Zhao Danielle L. Gray Jeffery A. Bertke Hong Yang Department of Chemical and Biomolecular Engineering University of Illinois at Urbana-Champaign MC-712 206 Roger Adams I Laboratory 600 S. Matthews Avenue Urbana Illinois 61801 USA George L. Clark X-ray Facility University of Illinois at Urbana-Champaign 505 S. Matthews Avenue Urbana Illinois 61801 USA

Unlike nucleation and growth in simple precipitation processes, described by the classical theory, metal nanoparticles formed in organic solvents with capping ligands often involve chemical reactions that occur homogeneously in solution or heterogeneously on the metal surface. These chemical reactions lead to the formation of intermediates that occurs in the process of deposition onto nuclei during the reduction. The understanding of these chemical reactions would enable a better design of functional metal nanocrystals, even those with unconventional hierarchical morphologies. In this study, we report the formation of dish-shaped nanostructures of palladium （Pd） obtained from palladium acetylacetonate （Pd（acac）2） in the presence of oleylamine and oleic acid. The process was correlated with the kinetic-controlled evolution of two-dimensional （2D） Pd nanosheets. The formation of Pd-ligand complexes was revealed using single-crystal X-ray diffraction, ultraviolet-visible spectroscopy, and mass spectrometry. These intermediates affected the formation kinetics of the 2D nanostructures and higher-ordered morphology of the nanodishes.

关键词： palladium nanoplates two-dimensional materials. complexation nucleation growth

complexation of poorly aqueous soluble drug risperidone with hydroxypropyl-β-cyclodextrin enhances its dissolution

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Chinese Pharmaceutical Sciences 2015年第1期24卷 47-53页

作者：马维娜谷福根王毅孟根达来吴春芝内蒙古医科大学药学院内蒙古呼和浩特010110 内蒙古医科大学附属医院药剂部内蒙古呼和浩特010050

In the present study, we investigated the complexation of risperidone with hydroxypropyl-β-cyclodextrin （HP-β-CD） in aqueous solution due to the poor water solubility and low oral bioavailability of risperidone in humans. The effect of temperature on the complexation was examined, and thermodynamic parameters of the complexation process, such as Gibbs free energy change （AG）, enthalpy change （AH） and entropy change （AS）, were also explored. Meantime, the solid dispersion of risperidone with HP-β-CD was prepared and confirmed by Fourier IR spectroscopy and X-ray diffractometry. The experimental results suggested that the complex of the drug with HP-β-CD at a molar ratio of 1：1 could form in aqueous solution, and the complexation was an endothermic and entropy-driven process. The risperidone-HP-β-CD solid dispersion exhibited a remarkable improvement in the dissolution rate of the drug. This might be attributed to the amorphous state, the enhanced wettability as well as the complex formation of the drug with HP-β-CD in aqueous solution.

关键词： Risperidone HP-β-CD complexation Solid dispersion Dissolution

Efficient purification of Al_(30) by organic complexation method

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2019年第6期31卷 240-247页

作者： Libing Liu Qinxue Yang Pin Wang Feng Xiao Ruyuan Jiao Guangyu An Dongsheng Wang University of Chinese Academy of Sciences State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Faculty Materials Science and Chemistry China University of Geosciences

A method was developed for preparing high purity Al30O8(OH)56(H2O)_(24)^(18)+(Al30) through elimination of impurities by *** chloride II(PAC_(30))with Al_(c )content of 75%was adopted as the source of Al_(30).The PAC_(30)was prepared under conditions of total aluminum concentration 0.1 mol/L and OH^-/Al ratio 2.2 to obtain the highest content of Al_(30).A precipitation/metathesis method,organic solvent precipitation method and organic complexation method were examined to separate and purify Al_(30).It was found that only by the organic complexation method could high purity Al_(30)products be obtained in large yield *** the experiments,benzoic acid was used as the coordinating reagent to decompose the main impurity AlO_4Al_(12)(OH)_(24)(H_2O)_(12)^(7+)(Al_(13)),and the Al_(30)product could be obtained by precipitation and metathesis *** was noteworthy that the decomposition of impurities by benzoic acid could be completed in 2 *** Al_(30)product was characterized by Ferron assay,^(27)Al-NMR,SEM,XRD and *** results showed that the purity of the Al_(30)product could exceed 92%.

关键词： Polyaluminum chloride(PAC) Al13 Al30 Organic complexation Precipitation/metathesis

Self-Assembled Film of Tb^(3+) and Poly(3- Thiophene Acetic Acid) via Layer-by-Layer complexation Technique and Its Photoluminescence

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2002年第5期20卷 333-338页

作者：辛颢李富友黄岩谊黄春辉 Lab. of Rare Earth Mat. Chem. Peking Univ. Beijing 100871 China

The layer by layer complexation technique of polymer and metal ion was successfully utilized to fabricate the ultrathin multilayer film of poly(3 thiophene acetic acid (PTAA) and Tb 3+ ion by dipping the substrates alternatively in polymer and Tb 3+ ion aqueous solutions. UV-vis measurement revealed that the absorbance has linearity with the bilayer number from layer to layer and the X ray photoelectron spectrum (XPS) confirmed the existence of Tb 3+ ion. The pH of both the polymer and TbCl 3 solutions influence the thickness dramatically while the concentration of the solutions is not so sensitive. The luminescent spectrum of the complex film shows the characteristic emission of Tb 3+ ion as well as the ligand indicating the formation of the complex.

关键词： rare earths self assembly terbium complexation layer by layer photoluminescence