The chelates of metal ions with EDTA covalently linked to the 5′end of oligodeoxyribonuclotides(ODN),i.e,ODN5′EDTA·M(Ⅱ),are prepared,in which M(Ⅱ) is Fe(Ⅱ),Co(Ⅱ) or Cu(Ⅱ).The optimum pH value for forming t...The chelates of metal ions with EDTA covalently linked to the 5′end of oligodeoxyribonuclotides(ODN),i.e,ODN5′EDTA·M(Ⅱ),are prepared,in which M(Ⅱ) is Fe(Ⅱ),Co(Ⅱ) or Cu(Ⅱ).The optimum pH value for forming these three chelates is calculated.For ODN5′EDTA Fe(Ⅱ) pH value is 5.8 to 8.6,pH 4.6～8.1 for ODN5′EDTA Co(Ⅱ),and pH 3.4～5.7 for ODN5′EDTA Cu(Ⅱ).Under such pH value conditions neither can Mg(Ⅱ) ion,necessary for cleavage reaction,be competitive with Fe(Ⅱ),Co(Ⅱ) or Cu(Ⅱ) to form EDTA chelate,nor can it be precipitated.The cleavage mechanism of ODN5′EDTA Fe(Ⅱ) for DNA duplex is discussed.Modified ODN binds with DNA duplex in the major groove via hydrogen bond to form triple helix.In the presense of oxygen and reducing agent dithiothreitol,hydroxyl radicals species are generated as intermediates by catalysis of metal ions,and then oxidize the ribo ring and cut the doublestranded DNA at the sites close to the EDTA· Fe(Ⅱ).展开更多
The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The result...The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The results showed that,the copper grade of the concentrate obtained from seawater flotation decreased to 24.30%,compared to 24.60%in DI water.Concurrently,the recovery of chalcopyrite decreased from 51.39%to 38.67%,while the selectivity index(SI)also had a reduction from 2.006 to 1.798.The incorporation of ethylene diamine tetraacetic acid(EDTA),sodium silicate(SS),and sodium hexametaphosphate(SHMP)yielded an enhancement in the SI value,elevating it from 1.798 to 1.897,2.250 and 2.153,separately.It is particularly noteworthy that an excess of EDTA resulted in a SI value of merely 1.831.The mechanism of action was elucidated through analysis of surface charge measurements,X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FT-IR),extended Derjaguin-Landau Verwey-Overbeek(E-DLVO)theory,and density functional theory(DFT)calculations.展开更多
Cadmium(Cd)or excess copper(Cu)has a great impact in terms of toxicity on living organisms as it severely affects crop growth,yield and food security;thus,warranting appropriate measures for the remediation of Cd or C...Cadmium(Cd)or excess copper(Cu)has a great impact in terms of toxicity on living organisms as it severely affects crop growth,yield and food security;thus,warranting appropriate measures for the remediation of Cd or Cu polluted soils.Phytoextraction of heavy metal(HM)using tolerant plants along with organic chelators has gained global attention,and this study provided further insights into this issue.Pot experiments were performed to evaluate the effects of different types of chelators[ethylenediamine tetraacetic acid(EDTA),ethylenediamine disuccinic acid(EDDS)and citric acid(CA)]to improve the phytoextraction capacity of Ricinus communis L.for the metals Cd and Cu.Contaminated soil from a copper smelter was used in this study.A rhizon soil sampler was used to determine the metal concentrations in soil pore water.The results indicated that R.communis was an adequate candidate for chelator induced phytoextraction under the experimental conditions and that EDDS would be a good candidate chelator for the phytoextraction of Cu in soils.EDTA addition obviously improved the uptake of Cd and Cu in R.communis;however,it posed the greatest risk because the concentration of HMs in soil pore water was very high even after 40 days.Compared with EDTA and EDDS,CA had few effects on Cd or Cu uptake in R.communis.Linear relationships between the metal uptake in R.communis shoots and the maximum HM concentrations in soil pore water under HM,2.5,5,and 10 mmol·kg^(-1) treatments were typically observed.From the results of this study,it could be concluded that EDDS treatments played a promising role in increasing the uptake of Cd or Cu and reducing its phytotoxicity.EDDS application could be an effective approach for the phytoextraction of Cd or Cu from polluted soils by growing Ricinus communis L.展开更多
Quinolone has a broad spectrum of synthetic antibiotics with a strong therapeutic effect and quinolone is a term used for chemical treatments used to treat a powerful bacteria.Quinolones are divided into 4 generations...Quinolone has a broad spectrum of synthetic antibiotics with a strong therapeutic effect and quinolone is a term used for chemical treatments used to treat a powerful bacteria.Quinolones are divided into 4 generations according to the bacterial spectrum,the majority of quinolones used clinically belong to the sub fluoroquinolones group,which has a fluorine atom linked to the central ring system,usually on its carbon atom 6 or 7.Herein in this article,six new nickel(Ⅱ)complexes(Ⅰ—Ⅵ)have been synthesized in aqueous alkaline media at pH ranged 8-9,the chemical reactions take place between levofloxacin(HLEV),lomefloxacin(HLOM),nalidixic acid(HNLA),oxolonic acid(HOXO),pipemidic acid(HPIP),and pefloxacin mesylate(HPEF)with nickel(Ⅱ)nitrate hexahydrate.The microanalytical(percentage of carbon,hydrogen and nitrogen),molar conductance(Λm),Infrared(FTIR)spectra,electronic(UV-Vis)spectra,and effective magnetic moment instrumentals were used to identify the suggested structures and their surface morphology.According the analytical and spectroscopic analyses,the stoichiometry between nickel(Ⅱ)metal ion and drug ligands was found to be 1∶2 with general formula as[Ni(L)_(2)(H_(2)O)_(2)]·x H_(2)O(L=LEV(Ⅰ),LOM(Ⅱ),NAL(Ⅲ),OXO(Ⅳ),PIP(V),and PEF(Ⅵ);x=2 or 4).By the comparison between FTIR spectra of quinolone drugs and their complexes,it can be deduced that all the drug ligands act as a bidentate chelates through oxygen atoms of pyridine ring and carboxylate group.The electronic configuration of all synthesized nickel(Ⅱ)complexes were octahedral geometry which confirmed based on the values of magnetic susceptibility and the electronic transition bands.展开更多
In the interest of accelerating aniline degradation, Fe2+ and chelated Fe2+ activated persulfate oxidations were investigated in neutral pH condition. Three kinds of chelating agents were selected including citric aci...In the interest of accelerating aniline degradation, Fe2+ and chelated Fe2+ activated persulfate oxidations were investigated in neutral pH condition. Three kinds of chelating agents were selected including citric acid, oxalic acid and ethylenediamine tetraaceatate(EDTA) to maintain available Fe2+. The results indicate that the concentration of chelating agent and ferrous ion didn't follow a linear relationship with the degradation rate of aniline. A 1/1 ratio of chelating agent/Fe2+ results in a higher degradation rate compared to the results by other ratios. The oxidation enhancement factor using oxalic acid was found to be relatively low. In contrast, citric acid is more suitable chelating agent in the ferrous iron activated persulfate system and aniline exhibits a highest degradation with a persulfate/Fe2+/citric acid/aniline molar ratio of 50/25/25/1 compared to other molar ratios.展开更多
This study presents the deep removal of copper (Ⅱ) from the simulated cobalt electrolyte using fabricated polystyrene-supported 2-aminomethylpyridine chelating resin (PS-AMP) in a fixed-bed.The effects of bed height ...This study presents the deep removal of copper (Ⅱ) from the simulated cobalt electrolyte using fabricated polystyrene-supported 2-aminomethylpyridine chelating resin (PS-AMP) in a fixed-bed.The effects of bed height (7.0–14.0 cm),feed flow rate (4.5–9.0 mL/min),initial copper (Ⅱ) concentration of the feed (250–1000 mg/L),feed temperature (25–40 ℃) and the value of pH (2.0–4.0) on the adsorption process of the PS-AMP resin were investigated.The experimental data showed that the PS-AMP resin can deeply eliminate copper (Ⅱ) from the simulated cobalt electrolyte.The bed height,feed flow rate,initial copper (Ⅱ) concentration of the feed,feed temperature and feed pH value which corresponded to the highest removal of copper (Ⅱ) were 7.0 cm with 35 mm of the column diameter,4.5 mL/min,40℃,1000 mg/L and 4.0,respectively.The breakthrough capacity,the saturated capacity of the column and the mass ratio of Cu/Co (g/g) in the saturated resin were correspondingly 16.51 mg/g dry resin,61.72 mg/g dry resin and 37.67 under the optimal experimental conditions.The copper (Ⅱ) breakthrough curves were fitted by the empirical models of Thomas,Yoon-Nelson and Adam-Bohart,respectively.The Thomas model was found to be the most suitable one for predicting how the concentration of copper (Ⅱ) in the effluent changes with the adsorption time.展开更多
To improve the adsorption properties of chemically modified chitosan, the chelating resin of salicylal chitosan Schiff bases was prepared by the template cross-linking method using Cu（Ⅱ） as template ion and ethylen...To improve the adsorption properties of chemically modified chitosan, the chelating resin of salicylal chitosan Schiff bases was prepared by the template cross-linking method using Cu（Ⅱ） as template ion and ethylene glycol bisglycidyl ether as cross-linking agent in microwave, and was characterized by IR. The adsorption capacity and selectivity coefficient of the chemically modified chitosan for Cu（Ⅱ）, Fe（Ⅲ） and Zn（Ⅱ） were investigated, respectively. The results show that the adsorption capacity of the resin 2.73 mmol/g for Cu（Ⅱ） is bigger than that for other two metal ions, 0.22 mmol/g for Fe（Ⅲ）, and 0.42 mmol/g for Zn（Ⅱ）, and the selectivity coefficients are as follows: KCu（Ⅱ）/Fe（Ⅲ）=12.4, KCu（Ⅱ）/Zn（Ⅱ）=6.5.展开更多
A novel chelating resin with sulfonic group was synthesized by chemical modification of D401 resin with sulphonation reaction and characterized by FT-IR spectrometry. The adsorption properties of the novel chelating r...A novel chelating resin with sulfonic group was synthesized by chemical modification of D401 resin with sulphonation reaction and characterized by FT-IR spectrometry. The adsorption properties of the novel chelating resin for Pb2+ were studied by batch adsorption, and the adsorption process was analyzed from thermodynamics and kinetics aspects. The adsorption mechanism of Pb2+ on the modified D401 chelating resin was discussed by FT-IR spectrometry. Experimental results show that in the Pb2+ concentration range of 200-400 mg/L, the adsorption capacities of the modified D401 chelating resin for Pb2+ increase by 77%-129%, and Langmuir isothermal adsorption model is more suitable for the equilibrium adsorption data. Adsorption is an endothermic process that runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best pH value under adsorption condition is 4-5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the adsorption capacity remains stable after five consecutive adsorption-desorption cycles. The maximal static saturated adsorption capacity of the resin is 206 mg/g at 333 K in the Pb2+ concentration range of 200-400 mg/L. The modified D401 chelating resin is an efficient adsorbent for the removal of Pb2+ from its single-metal ion solution.展开更多
PS-PAMAM-IDA chelating resins were prepared by low-generations of polyamidoamine(PAMAM) and then chloroacetic acid functionalizing commercially available ammoniated polystyrene matrix, to preconcentrate Ni2+ from synt...PS-PAMAM-IDA chelating resins were prepared by low-generations of polyamidoamine(PAMAM) and then chloroacetic acid functionalizing commercially available ammoniated polystyrene matrix, to preconcentrate Ni2+ from synthetic aqueous samples. Different generations of PAMAM were used to obtain different chelating resins, PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA. The synthesized resins were characterized by FTIR and elemental analysis. The effect of solution pH, kinetic studies, resin loading capacity, matrix effects etc., on metal ion adsorption to adsorbent phase, were studied by batch method. The PS-1.0G PAMAM-IDA resin was the most excellent adsorbents, with a maximum adsorption capacity of(24.09±1.79) mg/g for Ni2+ ion at pH=7. The interpretation of the equilibrium data was given by Langmuir isotherms model, and the correlation coefficient values for PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA resins were 0.992, 0.994 and 0.987, respectively.展开更多
Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),su...Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),sulfanilamide(sulp-2),sulfamethoxazole(sulp-3)and sulfadiazine(sulp-4).The microanalytical and spectroscopic analyses which utilized in this study were micro-analyses,magnetic,FT-IR,UV-Vis techniques.The mid infrared spectra deduced that the four sulfa-drug chelates acts as a bidentate chelates with scandium(Ⅲ)ion via two nitrogen atoms of-NH2-Ar and-NH-SO2 groups.Also,the FTIR spectra of Sc3+complexes referred to the existed of new medium weak bands in the range of 500~400 cm^-1 due to stretching vibration bands ofν(M-N).The elemental analysis technique confirmed the 1∶2 stoichiometry between Sc3+ions and sulp ligand with molecular formula[Sc(sulp)2(Cl)2]·Cl.At room temperature,the results of magnetic measurements for the Sc(Ⅲ)complexes indicated that all of the synthesized complexes have a diamagnetic character with octahedral configuration.The electronic spectra of the free sulfa-drug ligands shows band at 275 and 310 nm which are intraligand charge transfer band.The electronic sbsorption spectra of the Sc3+complexes were recorded using DMSO solvent.The spectra of complexes display bands within 275~388 nm,which attributed toπ-π*,n-π*and charge-transfer M-LCT electronic transitions,which strongly favors the octahedral geometry around Sc(Ⅲ)metal ions.1HNMR spectra of complexes referred to the downfield proton shifts of the-NH2 and NHSO2 groups,which supported the place of coordination.The half maximal inhibitory concentration(IC50)of the ScⅢcomplexes was assessed against the human hepato cellular carcinoma(HepG-2)tumor cell line.展开更多
The adsorption of Pd(Ⅱ), Pt(IV) and Cu(Ⅱ) in static and dynamic conditions on chemically modified silica containing sulfide sulfur (number of grafted functional groups of the sorbent was 0.2 (CMS-S 0.2) and 0 3 mmol...The adsorption of Pd(Ⅱ), Pt(IV) and Cu(Ⅱ) in static and dynamic conditions on chemically modified silica containing sulfide sulfur (number of grafted functional groups of the sorbent was 0.2 (CMS-S 0.2) and 0 3 mmol/g (CMS-S 0.3)) was studied. It is established that an increase in the acidity of the sorption of Pd(Ⅱ) and Pt(Ⅳ) decreases, whereas the Cu(Ⅱ) does not change. Time to reach the constant values of the sorption is 15 min. In equal conditions, the sorption decreases in the number of Pd(Ⅱ)>Pt(IV)>Cu(Ⅱ). Based on retrieved data suggested that the sorption of Pd(Ⅱ) proceeds according the coordination mechanism. In the case of sorption from solutions with a high palladium content can be polymerization of adsorbed complexes in the sorbent phase. Worked out the optimal conditions for the separation of pairs of Pd(Ⅱ)-Pt(Ⅳ) and Pd(Ⅱ)-Cu(Ⅱ) under dynamic conditions with the extraction of palladium(Ⅱ) in the eluate is above 95%.展开更多
The four isolates solid complexes:[La(RHC)(NO_(3))_(2)]·3H_(2)O,[Nd(RHC)(NO_(3))_(2)]·4H_(2)O,[Eu(RHC)(NO_(3))_(2)]·2H_(2)O,and[Ce(RHC)(NO_(3))_(2)]·5H_(2)O that obtained by the reaction of the nit...The four isolates solid complexes:[La(RHC)(NO_(3))_(2)]·3H_(2)O,[Nd(RHC)(NO_(3))_(2)]·4H_(2)O,[Eu(RHC)(NO_(3))_(2)]·2H_(2)O,and[Ce(RHC)(NO_(3))_(2)]·5H_(2)O that obtained by the reaction of the nitrate salts of the Ce(Ⅲ),Eu(Ⅲ),Nd(Ⅲ)and La(Ⅲ)ions and rhodamie C(RHC)ligand were interpretative using elemental analysis(C,H and N),molar conductivity,infrared,electronic,fluorescence and 1H-NMR spectra to achieve the speculated suitable formula.The low molar conductance values of the synthesized RHC complexes concluded the non-electrolytic behavior.The infrared spectra recorded the absence of stretching vibrationν(OH)of the—COOH and presence of two new vibration bands at 1597~1601 and 1383~1399 cm^(-1)which were assigned toνas(COO-)andνs(COO-).The difference between them revealed that the carboxylate group acts as a bidentate ligand.1HNMR spectra of Europium and lanthanum(Ⅲ)complexes were supported the FTIR results based on the absent of proton of the carboxylic group.Therefore,the microanalytical and spectroscopic results deduced that RHC acts as a monobasic bidentate ligand,and coordinated to the central metal(Ⅲ)ions via the two oxygen atoms of deprotonated carboxylic group.Fluorescence studies were performed on the metal complexes of Ce^(3+),Tb^(3+),Th^(4+),Gd^(3+)and La^(3+),that referred a quenching in the fluorescene intensity of rhodamine C in the aqueous state after complexation.The antimicrobial assessment against some kind of bacteria and fungi were also checked and recorded enhancement in case of their complexes.展开更多
Pipemidic acid is one of an efficient quinolone antibacterial drug.Thecomplexitybetween pipemidic acid“Hpipc”withgallium(Ⅲ),germanium(Ⅳ)and silicon(Ⅳ)afforded three molecular formulas of[Ga(pipc)2(H 2O)(Cl)]·...Pipemidic acid is one of an efficient quinolone antibacterial drug.Thecomplexitybetween pipemidic acid“Hpipc”withgallium(Ⅲ),germanium(Ⅳ)and silicon(Ⅳ)afforded three molecular formulas of[Ga(pipc)2(H 2O)(Cl)]·4H 2O,1,[Ge(pipc)2(Cl)2]·4H 2O,2 and[Si(pipc)2(Cl)2]·4H 2O,3 complexes.These three new complexes were characterized based on elemental analysis,conductance,FTIR,UV-Vis,^1HNMR and XRD spectroscopy.The pipc chelate exhibits O,O coordinated through the carbonyl(C O)and carboxylato(COO)of both oxygen atoms.Six coordinate geometry was proposed regarding complexes of 2 and 3,so the axial position was occupied by two coordinated chlorideatoms.In vitro,the antibacterial,antifungal,and anti-cancer assessments concerning the synthesized pipc complexes were scanned.These complexes have an excellent anti-microbial activity.展开更多
The relative abilities of several chelating agents to act as antagonists for acute and chronic lead poisoning have been examined in the mouse.The acute LD<sub>50</sub> for lead acetate trihydrate was deter...The relative abilities of several chelating agents to act as antagonists for acute and chronic lead poisoning have been examined in the mouse.The acute LD<sub>50</sub> for lead acetate trihydrate was determined and found to be 135.3 mg Pb/kg for i. p. injection with a 95% confidence interval of 87.1 to 210.3 mg Pb/kg. The relative efficacy of chelating agents to reduce liver,kidney, spleen, bone and brain levels of lead was determined. The spleen levels were found to undergo little differences between the control and treated groups, but the liver, kidney, bone and brain levels showed significant differences in some cases. Of the compounds examind, meso-2, 3-dimercaptosuccinic acid （DMSA）and sodium 2,3-dimercaptopropane-1-sulfonate（DMPS） were as effective as disodium calcium ethylenediaminetetraacetate （Na<sub>2</sub>CaEDT A）. The resuits indicated that DMSA was a promising chelating agent and may be worthy of further investigation in the clinic.展开更多
Te(Ⅳ),Se(Ⅳ),V(Ⅲ),Nb(Ⅴ)and Ta(Ⅴ)complexes of indole-3-acetic acid(IAAH)ligand were synthesized,characterized by elemental analysis and various spectroscopic techniques like,IR,1H-NMR,X-ray powder diffraction,UV-Vi...Te(Ⅳ),Se(Ⅳ),V(Ⅲ),Nb(Ⅴ)and Ta(Ⅴ)complexes of indole-3-acetic acid(IAAH)ligand were synthesized,characterized by elemental analysis and various spectroscopic techniques like,IR,1H-NMR,X-ray powder diffraction,UV-Visible,thermogravimetry analysis,magnetic measurements,molar conductance and surface morphology using SEM.All the synthesized complexes of IAAH ligand have 1∶2 stoichiometry of the types[Te(IAA)2(NH 3)2]·2Cl(Ⅰ),[Se(IAA)2(NH 3)2]·2Cl(Ⅱ),[V(IAA)2(NH 3)(Cl)](Ⅲ),[Nb(IAA)2(Cl)3](Ⅳ),and[Ta(IAA)2(Cl)3](Ⅴ).Spectral analysis indicates octahedral geometry for the Te(Ⅳ),Se(Ⅳ)and V(Ⅲ)complexes,whereas both Nb(Ⅴ)and Ta(Ⅴ)have a seven-coordination.The bonding sites are the oxygen atoms of carboxylate group for the deprotonated indole-3-acetic acid(IAA)ligand.The thermogravimetry analysis studies gave evidence for the presence of other coordinated molecules(Cl or NH 3)in the composition of IAA complexes,which were further supported by IR and micro analytical measurements.The higher molar conductance data of tellurium and selenium(Ⅳ)complexes reveal that these chelates are electrolytes,while low conductivity values for the vanadium(Ⅲ),niobium and tantalum(Ⅴ)chelates indicated a non-electrolytes.To test the antibacterial property of the five complexes in this study,four bacterial strains Klebsiella(G-),Escherichia coli(G-),Staphylococcus aureus(G+)and Staphylococcus epidermidis(G+)were used in the investigation.The effects of the five complexes in the cytotoxicity of Caco-2 and Mcf-7 human cancer cell lines were studied Neutral red uptake assay for the estimation of cell viability/cytotoxicity protocol.展开更多
The reaction of the ligands,ethylenediaminetetraacetic acid terasodium salt(Na 4EDTA)and N—N heterocyclic diamines like2,2’-bipyridine(bipy)with iron(Ⅱ)sulfate with 1∶2∶2 stoichiometric ratios form the mononuclea...The reaction of the ligands,ethylenediaminetetraacetic acid terasodium salt(Na 4EDTA)and N—N heterocyclic diamines like2,2’-bipyridine(bipy)with iron(Ⅱ)sulfate with 1∶2∶2 stoichiometric ratios form the mononuclear ternary complex of formulae,[Fe_(2)(EDTA)(bipy)2]at pH~7.The FTIR and Raman laser spectra of the iron(Ⅱ)complex show that 2,2’-bipyridine is present asa bidentate ligand and the ethylenediaminetetraacetic acid terasodium salt as monodentate carboxylate anion.The electronic spectra and magnetic moments data suggest the six coordination number.It has two iron(Ⅱ)centers in octahedral environments,which are interlinked by carboxylato-O atoms of ethylenediaminetetraacetate and by nitrogen atoms of the two 2,2-bipyridine ligands in a chelating mode.Thermal analysis study show thatiron(Ⅱ)complex containing EDTA and 2,2’-bipyridine on its thermalde composition form the corresponding Fe_(2)O_(3) oxide in nano size at the temperature range~475℃.The iron(Ⅱ)complex was performed as a convenient low cost precursor for the preparation of Fe_(2)O_(3) nanoparticles by the the thermal decomposition method.The iron(Ⅲ)oxide composition has been discussedusing FTIR,X-ray diffraction(XRD),transmission electron microscopy(TEM)and energy-dispersive X-ray spectroscopy(EDX).展开更多
Activity on catalytic reduction of C<sub>2</sub>H<sub>2</sub> for seven Mo-Fe-S cluster compounds (I. （Et<sub>4</sub>N<sub>4</sub>）<sub>4</sub>[Mo<sub&g...Activity on catalytic reduction of C<sub>2</sub>H<sub>2</sub> for seven Mo-Fe-S cluster compounds (I. （Et<sub>4</sub>N<sub>4</sub>）<sub>4</sub>[Mo<sub>2</sub>Fe<sub>2</sub>S<sub>10</sub>]·2CH<sub>3</sub>OH, Ⅱ. Mo<sub>2</sub>Fe<sub>2</sub>S<sub>4</sub>（S<sub>2</sub>CNEt<sub>2</sub>）<sub>5</sub>·CH<sub>3</sub>CN, Ⅲ. （Bu<sub>4</sub>N）<sub>3</sub> [Mo<sub>2</sub>FeS<sub>8</sub>O]·Ⅳ·（Et<sub>4</sub>N）<sub>3</sub>[Mo<sub>2</sub>FeS<sub>8</sub>O<sub>2</sub>], V. （Et<sub>4</sub>N）<sub>2</sub>[MoFeS<sub>4</sub>（SCN）<sub>2</sub>（OCH<sub>3</sub>）<sub>2</sub>]·3CH<sub>3</sub>OH, Ⅵ. （Et<sub>4</sub>N）<sub>3</sub>[Mo<sub>2</sub>FeS<sub>8</sub>O（OCH<sub>3</sub>）<sub>2</sub>], Ⅶ. （Et<sub>4</sub>N）<sub>4</sub>Mo<sub>2</sub>Fe<sub>7</sub>S<sub>12</sub>（SPh）<sub>6</sub>·6CH<sub>3</sub>OH), three Fe-S cluster compounds （Ⅷ.（Et<sub>4</sub>N）<sub>2</sub>[Fe<sub>4</sub>S<sub>4</sub>（S<sub>2</sub>CNEt<sub>2</sub>）<sub>4</sub>], Ⅸ. （Bu<sub>4</sub>N）<sub>2</sub>[Fe<sub>4</sub>S<sub>3</sub>（SC（CH<sub>3</sub>）<sub>3</sub>）<sub>4</sub>], Ⅹ. （Bu<sub>4</sub>N）[Fe<sub>2</sub>S<sub>3</sub>（SCH<sub>2</sub>Ph）<sub>2</sub>]） and combination systems of related compounds, has been determined under anaerobic conditions at 25℃ and with KBH<sub>4</sub> as the reductant. In addition, at 15℃, under otherwise the same conditions, activity on catalytic reduction of C<sub>2</sub>H<sub>2</sub> for different constituent systems from （NH<sub>4</sub>）<sub>2</sub>MoS<sub>4</sub> and FeCl<sub>3</sub> has also been determined.展开更多
In the presence of Rh（COD）（dppe）Cl （COD=1, 5-cyclootadiene, dppe=1,2-bis-（diphenylphosphino）ethane） and CO, we studied the H/Cl exchange reaction between CH<sub>4</sub> and o-dichlorobenzene, and o...In the presence of Rh（COD）（dppe）Cl （COD=1, 5-cyclootadiene, dppe=1,2-bis-（diphenylphosphino）ethane） and CO, we studied the H/Cl exchange reaction between CH<sub>4</sub> and o-dichlorobenzene, and observed that the active species of the reaction is a complex containing dppe and carbonyl ligands. We suggest that the mechanism of exchange reaction may be described by the elementary reaction of oxidative addition and reductive elimination. In the presence of trans-PtHL<sub>2</sub>X （L=PEt<sub>3</sub>, P（n-Pr）<sub>3</sub>, P（n-Bu）<sub>3</sub>, PPh<sub>3</sub>; X=Cl<sup>-</sup>, Br<sup>-</sup>, I<sup>-</sup>, CN<sup>-</sup>） complexes, we have studied the oxidative chlorination reaction of methane. The catalytic activity was found to be related to the electron-donating properties and the cone angle of tertiary phosphine, as well as the trans-effect of X anionic ligands. In addition to the above reactions, we have also studied the insertion reaction of acetylene into C-H bond of methane catalyzed by organotransition-metal complexes containing heterocyclic chelate ligands, such as bipy, phen and TMEDA, in展开更多
文摘The chelates of metal ions with EDTA covalently linked to the 5′end of oligodeoxyribonuclotides(ODN),i.e,ODN5′EDTA·M(Ⅱ),are prepared,in which M(Ⅱ) is Fe(Ⅱ),Co(Ⅱ) or Cu(Ⅱ).The optimum pH value for forming these three chelates is calculated.For ODN5′EDTA Fe(Ⅱ) pH value is 5.8 to 8.6,pH 4.6～8.1 for ODN5′EDTA Co(Ⅱ),and pH 3.4～5.7 for ODN5′EDTA Cu(Ⅱ).Under such pH value conditions neither can Mg(Ⅱ) ion,necessary for cleavage reaction,be competitive with Fe(Ⅱ),Co(Ⅱ) or Cu(Ⅱ) to form EDTA chelate,nor can it be precipitated.The cleavage mechanism of ODN5′EDTA Fe(Ⅱ) for DNA duplex is discussed.Modified ODN binds with DNA duplex in the major groove via hydrogen bond to form triple helix.In the presense of oxygen and reducing agent dithiothreitol,hydroxyl radicals species are generated as intermediates by catalysis of metal ions,and then oxidize the ribo ring and cut the doublestranded DNA at the sites close to the EDTA· Fe(Ⅱ).
基金Project(52174239)supported by the National Natural Science Foundation of ChinaProject(2021YFC2902400)supported by the National Key R&D Program of China。
文摘The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The results showed that,the copper grade of the concentrate obtained from seawater flotation decreased to 24.30%,compared to 24.60%in DI water.Concurrently,the recovery of chalcopyrite decreased from 51.39%to 38.67%,while the selectivity index(SI)also had a reduction from 2.006 to 1.798.The incorporation of ethylene diamine tetraacetic acid(EDTA),sodium silicate(SS),and sodium hexametaphosphate(SHMP)yielded an enhancement in the SI value,elevating it from 1.798 to 1.897,2.250 and 2.153,separately.It is particularly noteworthy that an excess of EDTA resulted in a SI value of merely 1.831.The mechanism of action was elucidated through analysis of surface charge measurements,X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FT-IR),extended Derjaguin-Landau Verwey-Overbeek(E-DLVO)theory,and density functional theory(DFT)calculations.
基金Supported by the Joint Funds of the National Natural Science Foundation of China(U2340219)。
文摘Cadmium(Cd)or excess copper(Cu)has a great impact in terms of toxicity on living organisms as it severely affects crop growth,yield and food security;thus,warranting appropriate measures for the remediation of Cd or Cu polluted soils.Phytoextraction of heavy metal(HM)using tolerant plants along with organic chelators has gained global attention,and this study provided further insights into this issue.Pot experiments were performed to evaluate the effects of different types of chelators[ethylenediamine tetraacetic acid(EDTA),ethylenediamine disuccinic acid(EDDS)and citric acid(CA)]to improve the phytoextraction capacity of Ricinus communis L.for the metals Cd and Cu.Contaminated soil from a copper smelter was used in this study.A rhizon soil sampler was used to determine the metal concentrations in soil pore water.The results indicated that R.communis was an adequate candidate for chelator induced phytoextraction under the experimental conditions and that EDDS would be a good candidate chelator for the phytoextraction of Cu in soils.EDTA addition obviously improved the uptake of Cd and Cu in R.communis;however,it posed the greatest risk because the concentration of HMs in soil pore water was very high even after 40 days.Compared with EDTA and EDDS,CA had few effects on Cd or Cu uptake in R.communis.Linear relationships between the metal uptake in R.communis shoots and the maximum HM concentrations in soil pore water under HM,2.5,5,and 10 mmol·kg^(-1) treatments were typically observed.From the results of this study,it could be concluded that EDDS treatments played a promising role in increasing the uptake of Cd or Cu and reducing its phytotoxicity.EDDS application could be an effective approach for the phytoextraction of Cd or Cu from polluted soils by growing Ricinus communis L.
基金the deanship of scientific Research at Princess Nourah bint Abdulrahman University through the Fast-track Research Funding program。
文摘Quinolone has a broad spectrum of synthetic antibiotics with a strong therapeutic effect and quinolone is a term used for chemical treatments used to treat a powerful bacteria.Quinolones are divided into 4 generations according to the bacterial spectrum,the majority of quinolones used clinically belong to the sub fluoroquinolones group,which has a fluorine atom linked to the central ring system,usually on its carbon atom 6 or 7.Herein in this article,six new nickel(Ⅱ)complexes(Ⅰ—Ⅵ)have been synthesized in aqueous alkaline media at pH ranged 8-9,the chemical reactions take place between levofloxacin(HLEV),lomefloxacin(HLOM),nalidixic acid(HNLA),oxolonic acid(HOXO),pipemidic acid(HPIP),and pefloxacin mesylate(HPEF)with nickel(Ⅱ)nitrate hexahydrate.The microanalytical(percentage of carbon,hydrogen and nitrogen),molar conductance(Λm),Infrared(FTIR)spectra,electronic(UV-Vis)spectra,and effective magnetic moment instrumentals were used to identify the suggested structures and their surface morphology.According the analytical and spectroscopic analyses,the stoichiometry between nickel(Ⅱ)metal ion and drug ligands was found to be 1∶2 with general formula as[Ni(L)_(2)(H_(2)O)_(2)]·x H_(2)O(L=LEV(Ⅰ),LOM(Ⅱ),NAL(Ⅲ),OXO(Ⅳ),PIP(V),and PEF(Ⅵ);x=2 or 4).By the comparison between FTIR spectra of quinolone drugs and their complexes,it can be deduced that all the drug ligands act as a bidentate chelates through oxygen atoms of pyridine ring and carboxylate group.The electronic configuration of all synthesized nickel(Ⅱ)complexes were octahedral geometry which confirmed based on the values of magnetic susceptibility and the electronic transition bands.
基金Project(2010B050200007)supported by the Foundation of Science and Technology Planning Project of Guangdong Province,ChinaProject(2011ZM0054)supported by the Fundamental Research Funds for the Central Universities,China+1 种基金Project(2011K0013)supported by the Research Fund Program of Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology,ChinaProject(2012)supported by the Research Funds of Guangdong Provincial Key Laboratory of Atmospheric environment and Pollution Control,China
文摘In the interest of accelerating aniline degradation, Fe2+ and chelated Fe2+ activated persulfate oxidations were investigated in neutral pH condition. Three kinds of chelating agents were selected including citric acid, oxalic acid and ethylenediamine tetraaceatate(EDTA) to maintain available Fe2+. The results indicate that the concentration of chelating agent and ferrous ion didn't follow a linear relationship with the degradation rate of aniline. A 1/1 ratio of chelating agent/Fe2+ results in a higher degradation rate compared to the results by other ratios. The oxidation enhancement factor using oxalic acid was found to be relatively low. In contrast, citric acid is more suitable chelating agent in the ferrous iron activated persulfate system and aniline exhibits a highest degradation with a persulfate/Fe2+/citric acid/aniline molar ratio of 50/25/25/1 compared to other molar ratios.
基金Project(2014CB643401)supported by the National Basic Research Program of ChinaProjects(51134007,51474256)supported by the National Natural Science Foundation of ChinaProject(2017TP1001)supported by the Hunan Provincial Science and Technology Plan Project,China
文摘This study presents the deep removal of copper (Ⅱ) from the simulated cobalt electrolyte using fabricated polystyrene-supported 2-aminomethylpyridine chelating resin (PS-AMP) in a fixed-bed.The effects of bed height (7.0–14.0 cm),feed flow rate (4.5–9.0 mL/min),initial copper (Ⅱ) concentration of the feed (250–1000 mg/L),feed temperature (25–40 ℃) and the value of pH (2.0–4.0) on the adsorption process of the PS-AMP resin were investigated.The experimental data showed that the PS-AMP resin can deeply eliminate copper (Ⅱ) from the simulated cobalt electrolyte.The bed height,feed flow rate,initial copper (Ⅱ) concentration of the feed,feed temperature and feed pH value which corresponded to the highest removal of copper (Ⅱ) were 7.0 cm with 35 mm of the column diameter,4.5 mL/min,40℃,1000 mg/L and 4.0,respectively.The breakthrough capacity,the saturated capacity of the column and the mass ratio of Cu/Co (g/g) in the saturated resin were correspondingly 16.51 mg/g dry resin,61.72 mg/g dry resin and 37.67 under the optimal experimental conditions.The copper (Ⅱ) breakthrough curves were fitted by the empirical models of Thomas,Yoon-Nelson and Adam-Bohart,respectively.The Thomas model was found to be the most suitable one for predicting how the concentration of copper (Ⅱ) in the effluent changes with the adsorption time.
文摘To improve the adsorption properties of chemically modified chitosan, the chelating resin of salicylal chitosan Schiff bases was prepared by the template cross-linking method using Cu（Ⅱ） as template ion and ethylene glycol bisglycidyl ether as cross-linking agent in microwave, and was characterized by IR. The adsorption capacity and selectivity coefficient of the chemically modified chitosan for Cu（Ⅱ）, Fe（Ⅲ） and Zn（Ⅱ） were investigated, respectively. The results show that the adsorption capacity of the resin 2.73 mmol/g for Cu（Ⅱ） is bigger than that for other two metal ions, 0.22 mmol/g for Fe（Ⅲ）, and 0.42 mmol/g for Zn（Ⅱ）, and the selectivity coefficients are as follows: KCu（Ⅱ）/Fe（Ⅲ）=12.4, KCu（Ⅱ）/Zn（Ⅱ）=6.5.
基金Project(708049) supported by the Important Item Cultivation Foundation of Scientific Innovation Project of Colleges and Universities of China
文摘A novel chelating resin with sulfonic group was synthesized by chemical modification of D401 resin with sulphonation reaction and characterized by FT-IR spectrometry. The adsorption properties of the novel chelating resin for Pb2+ were studied by batch adsorption, and the adsorption process was analyzed from thermodynamics and kinetics aspects. The adsorption mechanism of Pb2+ on the modified D401 chelating resin was discussed by FT-IR spectrometry. Experimental results show that in the Pb2+ concentration range of 200-400 mg/L, the adsorption capacities of the modified D401 chelating resin for Pb2+ increase by 77%-129%, and Langmuir isothermal adsorption model is more suitable for the equilibrium adsorption data. Adsorption is an endothermic process that runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best pH value under adsorption condition is 4-5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the adsorption capacity remains stable after five consecutive adsorption-desorption cycles. The maximal static saturated adsorption capacity of the resin is 206 mg/g at 333 K in the Pb2+ concentration range of 200-400 mg/L. The modified D401 chelating resin is an efficient adsorbent for the removal of Pb2+ from its single-metal ion solution.
基金Project(51074192)supported by the National Natural Science Foundation of China
文摘PS-PAMAM-IDA chelating resins were prepared by low-generations of polyamidoamine(PAMAM) and then chloroacetic acid functionalizing commercially available ammoniated polystyrene matrix, to preconcentrate Ni2+ from synthetic aqueous samples. Different generations of PAMAM were used to obtain different chelating resins, PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA. The synthesized resins were characterized by FTIR and elemental analysis. The effect of solution pH, kinetic studies, resin loading capacity, matrix effects etc., on metal ion adsorption to adsorbent phase, were studied by batch method. The PS-1.0G PAMAM-IDA resin was the most excellent adsorbents, with a maximum adsorption capacity of(24.09±1.79) mg/g for Ni2+ ion at pH=7. The interpretation of the equilibrium data was given by Langmuir isotherms model, and the correlation coefficient values for PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA resins were 0.992, 0.994 and 0.987, respectively.
文摘Herein,this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(Ⅲ)sulfa-drug complexes.The nomenclature and symbols of these drugs were sulfadimidine(sulp-1),sulfanilamide(sulp-2),sulfamethoxazole(sulp-3)and sulfadiazine(sulp-4).The microanalytical and spectroscopic analyses which utilized in this study were micro-analyses,magnetic,FT-IR,UV-Vis techniques.The mid infrared spectra deduced that the four sulfa-drug chelates acts as a bidentate chelates with scandium(Ⅲ)ion via two nitrogen atoms of-NH2-Ar and-NH-SO2 groups.Also,the FTIR spectra of Sc3+complexes referred to the existed of new medium weak bands in the range of 500~400 cm^-1 due to stretching vibration bands ofν(M-N).The elemental analysis technique confirmed the 1∶2 stoichiometry between Sc3+ions and sulp ligand with molecular formula[Sc(sulp)2(Cl)2]·Cl.At room temperature,the results of magnetic measurements for the Sc(Ⅲ)complexes indicated that all of the synthesized complexes have a diamagnetic character with octahedral configuration.The electronic spectra of the free sulfa-drug ligands shows band at 275 and 310 nm which are intraligand charge transfer band.The electronic sbsorption spectra of the Sc3+complexes were recorded using DMSO solvent.The spectra of complexes display bands within 275~388 nm,which attributed toπ-π*,n-π*and charge-transfer M-LCT electronic transitions,which strongly favors the octahedral geometry around Sc(Ⅲ)metal ions.1HNMR spectra of complexes referred to the downfield proton shifts of the-NH2 and NHSO2 groups,which supported the place of coordination.The half maximal inhibitory concentration(IC50)of the ScⅢcomplexes was assessed against the human hepato cellular carcinoma(HepG-2)tumor cell line.
文摘The adsorption of Pd(Ⅱ), Pt(IV) and Cu(Ⅱ) in static and dynamic conditions on chemically modified silica containing sulfide sulfur (number of grafted functional groups of the sorbent was 0.2 (CMS-S 0.2) and 0 3 mmol/g (CMS-S 0.3)) was studied. It is established that an increase in the acidity of the sorption of Pd(Ⅱ) and Pt(Ⅳ) decreases, whereas the Cu(Ⅱ) does not change. Time to reach the constant values of the sorption is 15 min. In equal conditions, the sorption decreases in the number of Pd(Ⅱ)>Pt(IV)>Cu(Ⅱ). Based on retrieved data suggested that the sorption of Pd(Ⅱ) proceeds according the coordination mechanism. In the case of sorption from solutions with a high palladium content can be polymerization of adsorbed complexes in the sorbent phase. Worked out the optimal conditions for the separation of pairs of Pd(Ⅱ)-Pt(Ⅳ) and Pd(Ⅱ)-Cu(Ⅱ) under dynamic conditions with the extraction of palladium(Ⅱ) in the eluate is above 95%.
基金Taif University Researches Supporting Project number(TURSP-2020/01),Taif University,Taif,Saudi Arabia。
文摘The four isolates solid complexes:[La(RHC)(NO_(3))_(2)]·3H_(2)O,[Nd(RHC)(NO_(3))_(2)]·4H_(2)O,[Eu(RHC)(NO_(3))_(2)]·2H_(2)O,and[Ce(RHC)(NO_(3))_(2)]·5H_(2)O that obtained by the reaction of the nitrate salts of the Ce(Ⅲ),Eu(Ⅲ),Nd(Ⅲ)and La(Ⅲ)ions and rhodamie C(RHC)ligand were interpretative using elemental analysis(C,H and N),molar conductivity,infrared,electronic,fluorescence and 1H-NMR spectra to achieve the speculated suitable formula.The low molar conductance values of the synthesized RHC complexes concluded the non-electrolytic behavior.The infrared spectra recorded the absence of stretching vibrationν(OH)of the—COOH and presence of two new vibration bands at 1597~1601 and 1383~1399 cm^(-1)which were assigned toνas(COO-)andνs(COO-).The difference between them revealed that the carboxylate group acts as a bidentate ligand.1HNMR spectra of Europium and lanthanum(Ⅲ)complexes were supported the FTIR results based on the absent of proton of the carboxylic group.Therefore,the microanalytical and spectroscopic results deduced that RHC acts as a monobasic bidentate ligand,and coordinated to the central metal(Ⅲ)ions via the two oxygen atoms of deprotonated carboxylic group.Fluorescence studies were performed on the metal complexes of Ce^(3+),Tb^(3+),Th^(4+),Gd^(3+)and La^(3+),that referred a quenching in the fluorescene intensity of rhodamine C in the aqueous state after complexation.The antimicrobial assessment against some kind of bacteria and fungi were also checked and recorded enhancement in case of their complexes.
基金funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University through the Fast-track Research Funding Program。
文摘Pipemidic acid is one of an efficient quinolone antibacterial drug.Thecomplexitybetween pipemidic acid“Hpipc”withgallium(Ⅲ),germanium(Ⅳ)and silicon(Ⅳ)afforded three molecular formulas of[Ga(pipc)2(H 2O)(Cl)]·4H 2O,1,[Ge(pipc)2(Cl)2]·4H 2O,2 and[Si(pipc)2(Cl)2]·4H 2O,3 complexes.These three new complexes were characterized based on elemental analysis,conductance,FTIR,UV-Vis,^1HNMR and XRD spectroscopy.The pipc chelate exhibits O,O coordinated through the carbonyl(C O)and carboxylato(COO)of both oxygen atoms.Six coordinate geometry was proposed regarding complexes of 2 and 3,so the axial position was occupied by two coordinated chlorideatoms.In vitro,the antibacterial,antifungal,and anti-cancer assessments concerning the synthesized pipc complexes were scanned.These complexes have an excellent anti-microbial activity.
文摘The relative abilities of several chelating agents to act as antagonists for acute and chronic lead poisoning have been examined in the mouse.The acute LD<sub>50</sub> for lead acetate trihydrate was determined and found to be 135.3 mg Pb/kg for i. p. injection with a 95% confidence interval of 87.1 to 210.3 mg Pb/kg. The relative efficacy of chelating agents to reduce liver,kidney, spleen, bone and brain levels of lead was determined. The spleen levels were found to undergo little differences between the control and treated groups, but the liver, kidney, bone and brain levels showed significant differences in some cases. Of the compounds examind, meso-2, 3-dimercaptosuccinic acid （DMSA）and sodium 2,3-dimercaptopropane-1-sulfonate（DMPS） were as effective as disodium calcium ethylenediaminetetraacetate （Na<sub>2</sub>CaEDT A）. The resuits indicated that DMSA was a promising chelating agent and may be worthy of further investigation in the clinic.
基金the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University,through the Research Groups Program Grant no.(RGP-1440-0001)。
文摘Te(Ⅳ),Se(Ⅳ),V(Ⅲ),Nb(Ⅴ)and Ta(Ⅴ)complexes of indole-3-acetic acid(IAAH)ligand were synthesized,characterized by elemental analysis and various spectroscopic techniques like,IR,1H-NMR,X-ray powder diffraction,UV-Visible,thermogravimetry analysis,magnetic measurements,molar conductance and surface morphology using SEM.All the synthesized complexes of IAAH ligand have 1∶2 stoichiometry of the types[Te(IAA)2(NH 3)2]·2Cl(Ⅰ),[Se(IAA)2(NH 3)2]·2Cl(Ⅱ),[V(IAA)2(NH 3)(Cl)](Ⅲ),[Nb(IAA)2(Cl)3](Ⅳ),and[Ta(IAA)2(Cl)3](Ⅴ).Spectral analysis indicates octahedral geometry for the Te(Ⅳ),Se(Ⅳ)and V(Ⅲ)complexes,whereas both Nb(Ⅴ)and Ta(Ⅴ)have a seven-coordination.The bonding sites are the oxygen atoms of carboxylate group for the deprotonated indole-3-acetic acid(IAA)ligand.The thermogravimetry analysis studies gave evidence for the presence of other coordinated molecules(Cl or NH 3)in the composition of IAA complexes,which were further supported by IR and micro analytical measurements.The higher molar conductance data of tellurium and selenium(Ⅳ)complexes reveal that these chelates are electrolytes,while low conductivity values for the vanadium(Ⅲ),niobium and tantalum(Ⅴ)chelates indicated a non-electrolytes.To test the antibacterial property of the five complexes in this study,four bacterial strains Klebsiella(G-),Escherichia coli(G-),Staphylococcus aureus(G+)and Staphylococcus epidermidis(G+)were used in the investigation.The effects of the five complexes in the cytotoxicity of Caco-2 and Mcf-7 human cancer cell lines were studied Neutral red uptake assay for the estimation of cell viability/cytotoxicity protocol.
基金Taif University Researches Supporting Project number(TURSP-2020/241),Taif University,Taif,Saudi Arabia。
文摘The reaction of the ligands,ethylenediaminetetraacetic acid terasodium salt(Na 4EDTA)and N—N heterocyclic diamines like2,2’-bipyridine(bipy)with iron(Ⅱ)sulfate with 1∶2∶2 stoichiometric ratios form the mononuclear ternary complex of formulae,[Fe_(2)(EDTA)(bipy)2]at pH~7.The FTIR and Raman laser spectra of the iron(Ⅱ)complex show that 2,2’-bipyridine is present asa bidentate ligand and the ethylenediaminetetraacetic acid terasodium salt as monodentate carboxylate anion.The electronic spectra and magnetic moments data suggest the six coordination number.It has two iron(Ⅱ)centers in octahedral environments,which are interlinked by carboxylato-O atoms of ethylenediaminetetraacetate and by nitrogen atoms of the two 2,2-bipyridine ligands in a chelating mode.Thermal analysis study show thatiron(Ⅱ)complex containing EDTA and 2,2’-bipyridine on its thermalde composition form the corresponding Fe_(2)O_(3) oxide in nano size at the temperature range~475℃.The iron(Ⅱ)complex was performed as a convenient low cost precursor for the preparation of Fe_(2)O_(3) nanoparticles by the the thermal decomposition method.The iron(Ⅲ)oxide composition has been discussedusing FTIR,X-ray diffraction(XRD),transmission electron microscopy(TEM)and energy-dispersive X-ray spectroscopy(EDX).
基金Project supported by the National Nartural Science Foundation of China
文摘Activity on catalytic reduction of C<sub>2</sub>H<sub>2</sub> for seven Mo-Fe-S cluster compounds (I. （Et<sub>4</sub>N<sub>4</sub>）<sub>4</sub>[Mo<sub>2</sub>Fe<sub>2</sub>S<sub>10</sub>]·2CH<sub>3</sub>OH, Ⅱ. Mo<sub>2</sub>Fe<sub>2</sub>S<sub>4</sub>（S<sub>2</sub>CNEt<sub>2</sub>）<sub>5</sub>·CH<sub>3</sub>CN, Ⅲ. （Bu<sub>4</sub>N）<sub>3</sub> [Mo<sub>2</sub>FeS<sub>8</sub>O]·Ⅳ·（Et<sub>4</sub>N）<sub>3</sub>[Mo<sub>2</sub>FeS<sub>8</sub>O<sub>2</sub>], V. （Et<sub>4</sub>N）<sub>2</sub>[MoFeS<sub>4</sub>（SCN）<sub>2</sub>（OCH<sub>3</sub>）<sub>2</sub>]·3CH<sub>3</sub>OH, Ⅵ. （Et<sub>4</sub>N）<sub>3</sub>[Mo<sub>2</sub>FeS<sub>8</sub>O（OCH<sub>3</sub>）<sub>2</sub>], Ⅶ. （Et<sub>4</sub>N）<sub>4</sub>Mo<sub>2</sub>Fe<sub>7</sub>S<sub>12</sub>（SPh）<sub>6</sub>·6CH<sub>3</sub>OH), three Fe-S cluster compounds （Ⅷ.（Et<sub>4</sub>N）<sub>2</sub>[Fe<sub>4</sub>S<sub>4</sub>（S<sub>2</sub>CNEt<sub>2</sub>）<sub>4</sub>], Ⅸ. （Bu<sub>4</sub>N）<sub>2</sub>[Fe<sub>4</sub>S<sub>3</sub>（SC（CH<sub>3</sub>）<sub>3</sub>）<sub>4</sub>], Ⅹ. （Bu<sub>4</sub>N）[Fe<sub>2</sub>S<sub>3</sub>（SCH<sub>2</sub>Ph）<sub>2</sub>]） and combination systems of related compounds, has been determined under anaerobic conditions at 25℃ and with KBH<sub>4</sub> as the reductant. In addition, at 15℃, under otherwise the same conditions, activity on catalytic reduction of C<sub>2</sub>H<sub>2</sub> for different constituent systems from （NH<sub>4</sub>）<sub>2</sub>MoS<sub>4</sub> and FeCl<sub>3</sub> has also been determined.
基金This work was supported by the Natural Science Foundation of China
文摘In the presence of Rh（COD）（dppe）Cl （COD=1, 5-cyclootadiene, dppe=1,2-bis-（diphenylphosphino）ethane） and CO, we studied the H/Cl exchange reaction between CH<sub>4</sub> and o-dichlorobenzene, and observed that the active species of the reaction is a complex containing dppe and carbonyl ligands. We suggest that the mechanism of exchange reaction may be described by the elementary reaction of oxidative addition and reductive elimination. In the presence of trans-PtHL<sub>2</sub>X （L=PEt<sub>3</sub>, P（n-Pr）<sub>3</sub>, P（n-Bu）<sub>3</sub>, PPh<sub>3</sub>; X=Cl<sup>-</sup>, Br<sup>-</sup>, I<sup>-</sup>, CN<sup>-</sup>） complexes, we have studied the oxidative chlorination reaction of methane. The catalytic activity was found to be related to the electron-donating properties and the cone angle of tertiary phosphine, as well as the trans-effect of X anionic ligands. In addition to the above reactions, we have also studied the insertion reaction of acetylene into C-H bond of methane catalyzed by organotransition-metal complexes containing heterocyclic chelate ligands, such as bipy, phen and TMEDA, in
