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Syntheses and Crystal Structures of Mono-and Binuclear Copper(Ⅱ) Mixed-ligand Complexes Involving Schiff Base 被引量:1
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作者 HOU Yin-Zhuang LI Jin-Fang TU Shu-Jie ZHANG Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第10期1193-1197,共5页
The mononuclear copper(Ⅱ) complex [Cu(L)(2-AP)] 1 and binuclear copper(Ⅱ) complex [Cu(L)(py)]2 2 (L = C10H11O5NS, taurine o-vanillin, py = prydine, 2-AP = 2-aminopyridine) with mixed ligand have been s... The mononuclear copper(Ⅱ) complex [Cu(L)(2-AP)] 1 and binuclear copper(Ⅱ) complex [Cu(L)(py)]2 2 (L = C10H11O5NS, taurine o-vanillin, py = prydine, 2-AP = 2-aminopyridine) with mixed ligand have been synthesized and characterized by X-ray diffraction method. Crystal data for 1: orthorhombic, space group Pbca with a = 11.921(4), b = 15.816(6), c = 17.076(6) A, V= 3219.7(19) A^3, C15H17CuN3O5S, Z = 8, Mr = 414.92, De = 1.712 g/cm^3,μ(MoKα) = 1.520 mm^-1, F(000) = 1704, the final R = 0.0300 and wR = 0.0705 for 2840 observed reflections with I 〉 2σ(I); and crystal data for 2: monoclinic, space group P21/c with a = 7.929(3), b = 17.038(5), c = 11.734(4) A, β = 98.162(6)°, V = 1569.1(9) A^3, C15H16CuN2O5S, Z = 4, Mr = 399.90, Dc = 1.693 g/cm^3, F(000) = 820,μ(MoKα) = 1.554 mm^-1, the final R = 0.0351 and wR = 0.0848 for 2767 observed reflections (I 〉 2σ(I)). The molecular structure of complex 1 consists of one tetra-coordinated Cu(Ⅱ) atom generating a slightly distorted square plane, and a one-dimensional chain structure is formed by intermolecular hydrogen bonds. Complex 2 consists of a diphenolic hydroxyl O-bridged binuclear copper(Ⅱ) structure. The crystal structures of complexes 1 and 2 reveal that the coordinate copper centers are bound to both nitrogen and oxygen atom donors. The usual N,O-trans arrangement of ligands is observed in both cases. 展开更多
关键词 SYNTHESIS mixed ligand copper complex crystal structure
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Spectra and DNA-binding Properties of Two Novel Mixed-ligand Complexes Containing Organosulfonate
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作者 李明田 黄俊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第2期181-185,共5页
Two novel mixed-ligand complexes, [M(phen)2(ans)2]·H2O (M = Cd(Ⅱ) 1, Zn(Ⅱ) 2; phen is 1, 10-phenanthroline, and ans is 4-aminonaphthalene-1-sulfonate), were obtained from the reaction of 1, 10-phenant... Two novel mixed-ligand complexes, [M(phen)2(ans)2]·H2O (M = Cd(Ⅱ) 1, Zn(Ⅱ) 2; phen is 1, 10-phenanthroline, and ans is 4-aminonaphthalene-1-sulfonate), were obtained from the reaction of 1, 10-phenanthroline, sodium 4-aminonaphthalene-1-sulfonate tetrahydrate and acetate in mixed solvents. Interaction of the complexes with calf thymus DNA (ctDNA) were investigated using UV-vis absorption spectra, luminescence titrations, steady-state emission quenching by [Fe(CN)6]4 , DNA competitive binding with ethidium bromide (EB) and viscosity measurements. The experimental results indicate that there exist two interaction modes between the complexes and DNA, namely the electrostatic interaction and intercalation, with the binding constants of 1.82 × 10^5 M-1 for 1 and 4.78 ×10^4 M^- 1 for 2 in buffer of 50 mM NaCl and 5 mM Tris-HCI (pH 7.0). 展开更多
关键词 CTDNA mixed-ligand complex interaction mode
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Triboluminescent Complexes of Rare Earth Ⅱ.Mixed-ligand Complexes of Eu^(3+) with Thenoyltrifluoroacetone and Pyridine-N-Oxide or its Substitutive Derivatives
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作者 朱文祥 花文滨 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第1期27-30,共4页
Five triboluminescent mixed-ligand complexes of Eu^(3+)with thenoyltrifluoroacetone(TTA)and pyridine-N-oxide or its substitutive derivatives have been prepared.They are all pale yellow crystalline com- pounds with the... Five triboluminescent mixed-ligand complexes of Eu^(3+)with thenoyltrifluoroacetone(TTA)and pyridine-N-oxide or its substitutive derivatives have been prepared.They are all pale yellow crystalline com- pounds with the formula of Eu(TTA)_3·L(L=py NO.2-pie NO,3-pie NO,4-pic NO,bipy N_2O_2).Their physico-chemical properties have been studied with conductometry,UV and IR absorption and fluorescence spectroscopy.Once the complexes are touched or rubbed by a glass rod,they emit strong red triboluminescent light which is similar to the characteristic fluorescence of Eu^(3+). 展开更多
关键词 Triboluminescent complexes mixed-ligand Eu^(3+) TTA Pyridme-N-oxide
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Synthesis and Physico-Chemical Characterizations of Novel Hydrazone Ligands and Their Metal Complexes against Hormone-Dependent and Independent Cancers
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作者 Sommai Patitungkho Kingkaew Patitungkho 《Open Journal of Medicinal Chemistry》 2024年第1期1-12,共12页
This work deals with the synthesis and physicochemical characterizations of a new group of novel retinoidal ligands and their metal complexes. Their in vitro anti-proliferative activities have shown that ligand L1 is ... This work deals with the synthesis and physicochemical characterizations of a new group of novel retinoidal ligands and their metal complexes. Their in vitro anti-proliferative activities have shown that ligand L1 is effective against human breast cancer BT-20 and MCF-7 cell lines. At the same time, compound L2 exerts its effect on human prostate cancer PC-3 and human breast cancer MDA-MB-231 and MCF-7 cell lines respectively. The retinoid ligands exert their pleiotropic action toward retinoic acid receptors (RARs) than their metal complexes but all compounds exhibit concentration-dependent. 展开更多
关键词 Metal complexes CANCERS ANTIOXIDANT Hydrazone Retinoid Receptors
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3,6-Bis-β-Dicarbonylsubstituted Carbazoles Bearing N-Spacers and Their Eu(III) Complexes as Immunofluorescent Labelling Agents
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作者 Dmitry E. Pugachev Georgy V. Zatonsky +2 位作者 Tatyana S. Kostryukova Anna G. Shubina Nikolay V. Vasiliev 《International Journal of Organic Chemistry》 2024年第1期20-31,共12页
New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carb... New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with Eu<sup>3+</sup> ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region. 展开更多
关键词 Fluorescence Immunoassay Fluorinated β-Diketones CARBAZOLE Europium complexes STREPTAVIDIN Nanodispersions
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Catalytic Effect of Transition Metal Complexes of Triaminoguanidine on the Thermolysis of Energetic NC/DEGDN Composite
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作者 Mohammed Dourari Ahmed Fouzi Tarchoun +4 位作者 Djalal Trache Amir Abdelaziz Roufaida Tiliouine Tessnim Barkat Weiqiang Pang 《火炸药学报》 EI CAS CSCD 北大核心 2024年第3期209-219,I0003,共12页
The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been prepared.The catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and ... The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been prepared.The catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and diethylene glycol dinitrate,has been investigated.Extensive characterization of the resulting energetic composites was carried out using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and differential scanning calorimetry(DSC).Isoconversional kinetic analysis was performed to determine the Arrhenius parameters associated with the thermolysis of the elaborated energetic formulations.It is found that TAG-M complexes have strong catalytic effect on the thermo-kinetic decomposition of NC/DEGDN by decreasing the apparent activation energy and significantly increased the total heat release.The models that govern the decomposition processes are also studied,and it is revealed that different reaction processes are accomplished by introduction metal complexes of triaminoguanidine.Overall,this study serves as a valuable reference for future research focused on the investigation of catalytic combustion features of solid propellants. 展开更多
关键词 triaminoguanidine transition metal complexes NITROCELLULOSE diethylene glycol dinitrate catalytic effect
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Intramolecular stacking interaction in mixed-ligand complexes containing ATP4-and aromatic N-heterocyclic ligands
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作者 乐学义 毋福海 +2 位作者 贺小凤 宋粉云 计亮年 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1998年第4期356-362,共7页
The stability constants of the binary ML2+ and ternary M(ATP)L2? complexes, where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+, have been determined by potentiometric pH titration in aqueous solution ... The stability constants of the binary ML2+ and ternary M(ATP)L2? complexes, where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+, have been determined by potentiometric pH titration in aqueous solution at I=0.1 mol/L (NaClO4), T=25°C. The stability of the ternary complexes characterized by ΔlogKM=logKM(ATP)LM(ATP)L- logKMML corresponding to the equilibrium M(ATP)2? + ML2+ = M(ATP)L2? + M2+ in higher than what would be expected on statistical grounds. The increase may be related to the stacking interaction between the aromatic ring of the ligands L and the purine moiety of ATP4–. 1H NMR studies of Zn2+/ATP4?/L confirm the presence of stacking in the ternary complexes. It is concluded that the strength of the intramolecular stacking interaction ia dependent on the structure of the aromatic ring of the ligand L and the formation of a metal ion bridge. Possible implications an discussed briefly. 展开更多
关键词 Stacking interaction mixed-ligand complexes aromatic N-heterocyclic ligands ATP4- stability constants
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Synergistic Optimization of Buried Interface by Multifunctional Organic-Inorganic Complexes for Highly Efficient Planar Perovskite Solar Cells 被引量:1
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作者 Heng Liu Zhengyu Lu +7 位作者 Weihai Zhang Hongkang Zhou Yu Xia Yueqing Shi Junwei Wang Rui Chen Haiping Xia Hsing-Lin Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期505-519,共15页
For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is ch... For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is challenging to effectively optimize this interface as it is buried beneath the perovskite film.Herein,we have designed and synthesized a series of multifunctional organic-inorganic(OI)complexes as buried interfacial material to promote electron extraction,as well as the crystal growth of the perovskite.The OI complex with BF4−group not only eliminates oxygen vacancies on the SnO_(2) surface but also balances energy level alignment between SnO_(2) and perovskite,providing a favorable environment for charge carrier extraction.Moreover,OI complex with amine(−NH_(2))functional group can regulate the crystallization of the perovskite film via interaction with PbI2,resulting in highly crystallized perovskite film with large grains and low defect density.Consequently,with rational molecular design,the PSCs with optimal OI complex buried interface layer which contains both BF4−and−NH_(2) functional groups yield a champion device efficiency of 23.69%.More importantly,the resulting unencapsulated device performs excellent ambient stability,maintaining over 90%of its initial efficiency after 2000 h storage,and excellent light stability of 91.5%remaining PCE in the maximum power point tracking measurement(under continuous 100 mW cm−2 light illumination in N2 atmosphere)after 500 h. 展开更多
关键词 Perovskite solar cells Organic Inorganic complexes Multifunctional interfacial material Buried interface layer
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DNA-free genome editing in grapevine using CRISPR/Cas9 ribonucleoprotein complexes followed by protoplast regeneration
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作者 Samaneh Najafi Edoardo Bertini +2 位作者 Erica D’Incà Marianna Fasoli Sara Zenoni 《Horticulture Research》 SCIE CSCD 2023年第1期183-192,共10页
CRISPR/Cas9 genome editing technology can overcome many limitations of traditional breeding,offering enormous potential for crop improvement and food production.Although the direct delivery of Cas9-single guide RNA(sg... CRISPR/Cas9 genome editing technology can overcome many limitations of traditional breeding,offering enormous potential for crop improvement and food production.Although the direct delivery of Cas9-single guide RNA(sgRNA)ribonucleoprotein(RNP)complexes to grapevine(Vitis vinifera)protoplasts has been shown before,the regeneration of edited protoplasts into whole plants has not been reported.Here,we describe an efficient approach to obtain transgene-free edited grapevine plants by the transfection and subsequent regeneration of protoplasts isolated from embryogenic callus.As proof of concept,a single-copy green f luorescent protein reporter gene(GFP)in the grapevine cultivar Thompson Seedless was targeted and knocked out by the direct delivery of RNPs to protoplasts.CRISPR/Cas9 activity,guided by two independent sgRNAs,was confirmed by the loss of GFP f luorescence.The regeneration of GFP−protoplasts into whole plants was monitored throughout development,confirming that the edited grapevine plants were comparable in morphology and growth habit to wild-type controls.We report the first highly efficient protocol for DNA-free genome editing in grapevine by the direct delivery of preassembled Cas9-sgRNA RNP complexes into protoplasts,helping to address the regulatory concerns related to genetically modified plants.This technology could encourage the application of genome editing for the genetic improvement of grapevine and other woody crop plants. 展开更多
关键词 complexes FIR EDITING
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Encapsulation of Ru(II) Polypyridine Complexes for Tumor-Targeted Anticancer Therapy
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作者 Johannes Karges 《Biomedical Engineering Frontiers》 CAS 2023年第1期52-65,共14页
Ru(II)polypyridine complexes have attracted much attention as anticancer agents because of their unique photophysical,photochemical,and biological properties.Despite their promising therapeutic profile,the vast majori... Ru(II)polypyridine complexes have attracted much attention as anticancer agents because of their unique photophysical,photochemical,and biological properties.Despite their promising therapeutic profile,the vast majority of compounds are associated with poor water solubility and poor cancer selectivity.Among the different strategies employed to overcome these pharmacological limitations,many research efforts have been devoted to the physical or covalent encapsulation of the Ru(II)polypyridine complexes into nanoparticles.This article highlights recent developments in the design,preparation,and physicochemical properties of Ru(II)polypyridine complex-loaded nanoparticles for their potential application in anticancer therapy. 展开更多
关键词 properties. PYRIDINE complexes
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Synthesis and Spectral Properties of Mixed-Ligand Complexes of Lanthanide Perchlorate with Bis-(phenylsulfinyl)ethane and Organic Lewis Bases 被引量:1
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作者 张若桦 卜显和 +1 位作者 孙心琳 王永生 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第2期11-15,共5页
Six lanthanide complexes with bis(phenylsulfinyl)ethane(bphse) and organic bases(phen: 1,10 phenanthroline and bipy: 2,2'-bipyridine) were synthesized and characterized by elemental analysis, conductance and spec... Six lanthanide complexes with bis(phenylsulfinyl)ethane(bphse) and organic bases(phen: 1,10 phenanthroline and bipy: 2,2'-bipyridine) were synthesized and characterized by elemental analysis, conductance and spectral (IR, UV Visible) data. The complexes were Ln(bphse) 2(bipy)(ClO 4) 3· n H 2O and Ln 2(bphse) 3(phen) 2(ClO 4) 6·H 2O(where Ln=Nd, Eu and Gd; n =0~2). IR spectral data confirmed that the lanthanide ions were coordinated by oxygen atoms from bphse and nitrogen atoms from phen or bipy. Exitation and emission spectra of Eu complexes were measured and discussed. 展开更多
关键词 Rare earths complex synthesis Spectral properties Bis(phenylsulfinyl)ethane Organic bases
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Pathfinder-Based Simulation and Optimization of Evacuation of Large Commercial Complexes
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作者 Jiuju Liu Shuhan Li 《Journal of Building Construction and Planning Research》 2023年第2期27-35,共9页
Large commercial complexes are large in scale, complex in function, and located in densely populated areas that are prone to casualties due to unfavorable evacuation. To comprehend the safety evacuation of large comme... Large commercial complexes are large in scale, complex in function, and located in densely populated areas that are prone to casualties due to unfavorable evacuation. To comprehend the safety evacuation of large commercial complex buildings in China, investigate the safety evacuation problems encountered during the evacuation process and the evacuation optimization design strategy, the paper uses Pathfinder to build a simulation model based on literature research and study to simulate the evacuation of personnel in a large commercial complex in Dalian and explore its problems during the evacuation process. The results show that the type of personnel has an effect on the large commercial complex’s evacuation simulation results;the total number of evacuees is non-linearly correlated with the time change curve;some staircases take a long time to evacuate and have a low utilization rate. To improve evacuation efficiency, optimization suggestions for safety exits, evacuation stairs, and evacuation channels are made based on the results. 展开更多
关键词 Commercial complex Safe Evacuation SIMULATION PATHFINDER
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Coordination behavior of N-benzoylamino acids: Synthesis and structure of mixed-ligand complexes of palladium(Ⅱ) with N-benzoylamino acid dianion and diamine 被引量:1
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作者 龚钰秋 陈耀峰 +1 位作者 顾建明 胡秀荣 《Science China Chemistry》 SCIE EI CAS 1997年第6期600-607,共8页
Four new mixed-ligand complexes of pailadiumt(Ⅱ) with L1(N-benzoyl-α-amino acid dianion) and L2[ethyldiamine (en),2,2’-bipyridine (Bpy) and 1,10-phenanthroline (Phen)] were synthesized.Ail the complexes have been c... Four new mixed-ligand complexes of pailadiumt(Ⅱ) with L1(N-benzoyl-α-amino acid dianion) and L2[ethyldiamine (en),2,2’-bipyridine (Bpy) and 1,10-phenanthroline (Phen)] were synthesized.Ail the complexes have been characterized by elemental analyses,molar conductance,infrared and 1H NMR spectra and therme-gravimetric analyses.Crystal structures of [Pd(Bpy)(Bzval-N,O)] and [Pd(en) (Bzphe-N,O)] H2O have been do termmed by X-ray diffraction analysis.The results indicate that in all the complexes hgand L1 coordinates to palladium (Ⅱ) through deprotonated amide nitrogen and carboxylic oxygen,and there are some intramolecular nonrovalent in teractions in the complexes. 展开更多
关键词 N-benzoyl-a-amino acid palladium(II) complexes containing deprotonated amide group molecular STRUCTURE intramolecular NONCOVALENT interaction
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Mixed-Ligand Ni(Ⅱ), Co(Ⅱ) and Fe(Ⅱ) Complexes as Catalysts for Esterification of Biomass-Derived Levulinic Acid with Polyol and in Situ Reduction via Hydrogenation with NaBH_(4)
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作者 Md.Anwar Hossain Lee Hwei Voon 《Journal of Renewable Materials》 SCIE 2019年第8期731-748,共18页
Synthesizing polyol-based ester from biomass feedstocks for the preparation of biolubricant overcomes the dependence on petroleum oil usage.Albeit biomass-derived bio-oil is an alternative for the production of polyol... Synthesizing polyol-based ester from biomass feedstocks for the preparation of biolubricant overcomes the dependence on petroleum oil usage.Albeit biomass-derived bio-oil is an alternative for the production of polyol ester,upgrading is essential prior to use as biolubricant.Levulinic acid(LA),obtained from bio-oil was applied for the catalytic esterification with two polyols,e.g.,trimethylolpropane(TMP)and pentaerythritol(PE),in the presence of mixed-ligand Ni(Ⅱ),Co(Ⅱ),and Fe(Ⅱ)complexes as catalyst.New mixed-ligand coordination complexes with empirical formula;[Ni(Phe)(Bpy)Cl].H2O,[Co(Phe)(Bpy)Cl].H2O,and[Fe(Phe)(Tyr)Cl].H2O were synthesized by the reaction of ligands[L-phenylalanine(Phe),4,4'-bipyridine(Bpy),and L-tyrosine(Tyr)]with metal chloride salts and characterized by elemental analysis,magnetic susceptibility,FTIR,TGA/DTA,powder-XRD,and SEM techniques.This study aims to investigate the catalytic activities of the complexes via esterification reaction of levulinic acid with trimethylolpropane and pentaerythritol.In addition,these catalysts were further employed for the in situ hydrogenation of levulinate esters via NaBH_(4) at room temperature upon refluxing.Indeed,the iron(Ⅱ)complex was more potential,exhibiting its efficiency as a homogeneous catalyst for esterification-hydrogenation reaction for synthesizing ester-based oils. 展开更多
关键词 BIOMASS esterification-hydrogenation mixed-ligand complex NaBH_(4) reduction
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Synthesis and Characterisation of Cr(III) and Co(II) Schiff Base Complexes
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作者 Fatin M. Elmagbari Ahmed N. Hammouda +2 位作者 Hamdi A. M. Bennour Rashd M. EL-Ferjani Younis O. Ben Amer 《Materials Sciences and Applications》 CAS 2023年第2期53-62,共10页
Co(II) and Cr(III) metal complexes of Schiff bases were synthesized from the condensation reaction between 4-(dimethylamino)benzaldehyde and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid. Their structures were investi... Co(II) and Cr(III) metal complexes of Schiff bases were synthesized from the condensation reaction between 4-(dimethylamino)benzaldehyde and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid. Their structures were investigated by elemental analysis, molar conductance measurements, infrared spectroscopy, electronic spectroscopy, and 1HNMR spectroscopy. The elemental analysis data suggested a 1:1 [M:L] ratio for the complexes. The molar conductance measurements of the complexes indicate their electrolytic nature in DMSO as a solvent. The absorption bands in the electronic spectra verified an octahedral environment around the metal ions in the complexes. 展开更多
关键词 Schiff Base Ligand complexes 1HNMR Spectra
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2,4-Dinitrophenyl Ether of Polyvinyl Alcohol and Polymer Bound Anionic SIGMA Complexes
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作者 John C. Phelan Michael J. Strauss 《International Journal of Organic Chemistry》 2023年第3期87-95,共9页
A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP ... A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP polymer was characterized by NMR, IR, and UV-visible spectroscopy. The reaction of PVA-DNP with sodium methoxide was followed by NMR and UV-visible spectroscopy. Evidence of polymer bound spirocyclic SIGMA complex, C-1 and C-3 polymer bound DNP-methoxy SIGMA complexes and the formation and C-1 methoxy complex of 2,4-dinitroanisole was observed. 展开更多
关键词 2 4-Dinitrophenyl Ether Polyvinyl Alcohol Anionic SIGMA complex Thermal Stability Nucleophilic Aromatic Substitution
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A Theoretical Study of Tris-(o-benzoquinonediimine)-First-Row Divalent Transition Metal Complexes
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作者 Mohammad Abdul Matin Samiran Bhattacharjee Anwar Hossain 《Advances in Chemical Engineering and Science》 CAS 2023年第2期172-188,共17页
The ligand o-phenylenediamine (opda) and its oxidized form, o-benzoquinonediimine (bqdi), act as a fascinating candidate coordinating toward transition metal ions leading to the photochemical hydrogen production in ab... The ligand o-phenylenediamine (opda) and its oxidized form, o-benzoquinonediimine (bqdi), act as a fascinating candidate coordinating toward transition metal ions leading to the photochemical hydrogen production in absence of photosensitizers. Herein, we report the systematic study of the interaction between the oxidized form bqdi ligand, tris-(o-benzoquinonediimine) with divalent first-row transition metal series using DFT calculations. The lowest energy structures, bond length, binding energies, frontier molecular orbital analysis, natural bond orbitals, and global reactivity descriptor were calculated using B3LYP/6-311G(d,P) level of theory. The time dependent-DFT at the CAM-B3LYP/6-311+G(d,p) level of theory was applied to determine the electronic structures and the optical spectra. The theoretical binding trend of the divalent first-row transition metal series is decreasing as follows: Cu >Ti > V > Co > Ni > Fe > Cr > Zn >Mn. Among them, the binding potency of iron (II) by the bqdi ligand was not predominantly sturdy as compared to other first-row divalent transition metal ions. The origin of strong coordination with Fe(II) is attributed to its extra capability to induce covalent coordination of bqdi ligands. The complex exhibited two strong peaks at 370 nm and 452 nm, due to the HOMO-3 to LUMO+1 and HOMO-1 to LUMO transitions, respectively. Natural bond orbital analysis showed that the major interaction happens between the N lone pair electrons of the ligand with an anti-bonding orbital of metal ions, in which Ti showed the highest interaction energy than other metal ions. The present systemic DFT study of bqdi ligands with the first-row transition metals strongly encourages the future establishment of photochemical hydrogen production in absence of photosensitizers. 展开更多
关键词 DFT O-PHENYLENEDIAMINE o-benzoquinodiimine First-Row Divalent Transition Metals Time Dependent–DFT Coordination complexes
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Probing electronic structures of transition metal complexes using electron paramagnetic resonance spectroscopy
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作者 Shengfa Ye 《Magnetic Resonance Letters》 2023年第1期43-60,I0003,共19页
Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,h... Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,how to extract the underlying electronicstructure information inevitably poses a major challenge to beginners,in particular for systems with S>1/2.In fact,the physical principles of transition metal EPR have long been well-established and since 1970s a series of dedicated voluminous monographs have been published already.Not surprisingly,they are not appropriate stating points for novices to grasp a panorama of the profound theory prior to scrutinizing in-depth references.The present review aims to fill this gap to provide a perspective of transition metal EPR and unveil some peculiar subtleties thereof on the basis of our recent work. 展开更多
关键词 EPR Electronic structures Transition metal complexes Spin Hamiltonian
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A novel complex-high-order graph convolutional network paradigm:ChyGCN
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作者 郑和翔 苗书宇 顾长贵 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期665-672,共8页
In recent years,there has been a growing interest in graph convolutional networks(GCN).However,existing GCN and variants are predominantly based on simple graph or hypergraph structures,which restricts their ability t... In recent years,there has been a growing interest in graph convolutional networks(GCN).However,existing GCN and variants are predominantly based on simple graph or hypergraph structures,which restricts their ability to handle complex data correlations in practical applications.These limitations stem from the difficulty in establishing multiple hierarchies and acquiring adaptive weights for each of them.To address this issue,this paper introduces the latest concept of complex hypergraphs and constructs a versatile high-order multi-level data correlation model.This model is realized by establishing a three-tier structure of complexes-hypergraphs-vertices.Specifically,we start by establishing hyperedge clusters on a foundational network,utilizing a second-order hypergraph structure to depict potential correlations.For this second-order structure,truncation methods are used to assess and generate a three-layer composite structure.During the construction of the composite structure,an adaptive learning strategy is implemented to merge correlations across different levels.We evaluate this model on several popular datasets and compare it with recent state-of-the-art methods.The comprehensive assessment results demonstrate that the proposed model surpasses the existing methods,particularly in modeling implicit data correlations(the classification accuracy of nodes on five public datasets Cora,Citeseer,Pubmed,Github Web ML,and Facebook are 86.1±0.33,79.2±0.35,83.1±0.46,83.8±0.23,and 80.1±0.37,respectively).This indicates that our approach possesses advantages in handling datasets with implicit multi-level structures. 展开更多
关键词 raph convolutional network complex modeling complex hypergraph
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Synthesis, Characterization and Antimicrobial Screening Mixed-Ligand Cu(II) and Zn(II) Complexes;DNA Binding Studies on Cu(II) Complex
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作者 Omar H. Al-Obaidi 《Open Journal of Inorganic Non》 2012年第4期59-64,共6页
Several mixed ligand Cu(II), Zn(II) complexes using (benzylidenethiourea) (obtained by the condensation of benzaldehyde and thiourea) as the primary ligand and (acetamide or thioacetamide) as an additional ligand were... Several mixed ligand Cu(II), Zn(II) complexes using (benzylidenethiourea) (obtained by the condensation of benzaldehyde and thiourea) as the primary ligand and (acetamide or thioacetamide) as an additional ligand were synthesized and characterized analytically and spectroscopically, magnetic susceptibility and molar conductance measurements ,as well as by UV-Vis. and IR spectroscopy. The interaction of the complexes with calf thymus (CT)DNA was studied using absorption spectra, while the concentration of DNA in gel electrophoresis remained constant at 10 μl. They exhibit absorption hypochromicity increased during the binding of the complexes to calf thymus DNA. The complexes show enhanced antimicrobial activities complexes with the free ligand. A theoretical treatment of the formation of complexes in the gas phase was studied, this was done using the HYPERCHEM-6 program for the Molecular mechanics and Semi-empirical calculations. 展开更多
关键词 mixed-ligand complexes THIOUREA THIOACETAMIDE DNA Binding
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