2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(...2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(4)H_(2)N)C_(6)H4NC(Ph)=NDipp]-,Dipp=2,6-iPr_(2)C_(6)H_(3))were investigated.The 1H NMR spectroscopy indicate that the reaction of ytrrium dialkyl complex with one equivalent of 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10) produce the mixture of ytrrium alkyl-amido complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))(CH_(2)SiMe3)](R=CH_(3),2a;R=Ph,2b)and bis(amido)complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))_(2)](R=CH_(3),3a;R=Ph,3b).The yttrium bridging imido complex[Y(L)(2-CH_(3)-1-N-o-C_(2)B_(10)H_(10))]_(2)(4a)was obtained by heating the mixture at 55℃for 12 h.Complex 3a was isolated and characterized by treating the yttrium dialkyl complex with two equivalents of 1a.The structures of complexes 3a and 4a were verified by single-crystal Xray diffraction.CCDC:2424136,3a;2424137,4a.展开更多
This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of use...This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of uses.An overview of the current trends in nanoglass research connects them to the Sustainable Development Goals,highlighting the current relevance of this topic.The process of manufacturing nanoglasses is explained in depth,highlighting advanced approaches such as inert gas condensation and severe plastic deformation,among other techniques.The prime focus of this review is on analyzing the various dimensions of nanoglass materials,including their structural dynamics and electrical configurations,and how these features contribute to their exceptional thermal stability and mechanical strength.The magnetic characteristics of nanoglasses are examined,highlighting their potential for driving innovation across multiple industries.The primary emphasis is on the biological usefulness of nanoglasses,specifically examining their bioactivity and interaction with biological components,and emphasizing their growing use in nanoscale biomedical applications.With regard to the practical applications of nanoglasses,there are specific discussions of their contributions to biological evaluation,wound healing,catalysis,and environmental sustainability.There is an emphasis on the durability and resistance of nanoglasses in these contexts.The comprehensive overview of nanoglasses provided in this article highlights their significance as revolutionary materials in fields of science and technology.The potential of nanoglasses to contribute to a future that is more sustainable and health oriented is indicated.The article ends by discussing the future directions for nanoglass research and looks forward to the promising possibilities for further investigation and innovation.展开更多
High-purity SiO_(2)nanoparticles(SNPs)play a crucial role in various electronic applications,such as semiconductors,solar cells,optical fibers,lenses,and insulating layers,given their purity and particle size,which si...High-purity SiO_(2)nanoparticles(SNPs)play a crucial role in various electronic applications,such as semiconductors,solar cells,optical fibers,lenses,and insulating layers,given their purity and particle size,which significantly impact device efficiency.This study fo-cuses on the synthesis and characterization of pure SNPs through the chemical etching of greater club rush.White powder SNPs were pre-pared using HCl etching,and their thermal behaviors were analyzed via thermogravimetric analysis/differential scanning calorimetry.Structural properties were investigated using X-ray fluorescence,scanning electron microscopy,and transmission electron microscopy.X-ray absorption near-edge structure was employed to assess the oxidation state of the SNPs.The morphology of the SNPs after the first etching was amorphous,with sizes ranging from 50 to 100 nm,which increased to 50-200 nm after the second etching.Despite this size variation,the SNPs maintained a high purity level of 99.8wt%SiO_(2),comparable with industry standards.Notably,the second etching with 0.1-M HCl significantly enhanced the purity level,achieving 99.8wt%SiO_(2)mass.Furthermore,HCl etching facilitated the formation of SiO_(2)in the Si^(4+)oxidation state,akin to industrial SNPs.These findings underscore the critical role of HCl etching in synthesizing high-purity SNPs,with potential applications in advanced electronic devices.展开更多
High molecular weight poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate)copolyesters(PBSIF-x)were synthesized via melt-polycondensation of 2,5-furandicarboxylic acid(FDCA),with varying rati...High molecular weight poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate)copolyesters(PBSIF-x)were synthesized via melt-polycondensation of 2,5-furandicarboxylic acid(FDCA),with varying ratios of isosorbide(ISB)and 1,4-butylene glycol(BDO)catalyzed by antimony trioxide(Sb_(2)O_(3)).The PBSIF-x structures were investigated using FTIR and~1H NMR,while the GPC analysis exhibited the copolyesters molecular weights with number average molecular mass(M_n)in the range of 11079-15153 g/mol.The DSC results show that PBSIF-x copolyesters have a single glass-transition temperature(T_(g))(77.45-110.96℃),increasing with the increase in ISB content,while TGA analysis demonstrates excellent thermal stability up to 320℃.From the thermal result,properties of PBSIF-x copolyesters are found to be within the interval of their parent homologues poly(butylene 2,5-furandicarboxylate)(PBF)and poly(isosorbide 2,5-furandicarboxylate)(PIF),which confirms the aromatic/aliphatic blending within the polymer matrix for enhanced polymer stability and performance.展开更多
Vanadium （III） phosphate monoclinic VPO4·H2O was synthesized hydrothermally. The ε-VOPO4 nanosheets, formed by the oxidative de-intercalation of protons from monoclinic VPO4·H2O, can reversibly react wit...Vanadium （III） phosphate monoclinic VPO4·H2O was synthesized hydrothermally. The ε-VOPO4 nanosheets, formed by the oxidative de-intercalation of protons from monoclinic VPO4·H2O, can reversibly react with more than 1 mol lithium atoms in two steps. Crystal XRD analysis revealed that the structure of the ε-VOPO4 nanosheets is monoclinic with lattice parameters of α=7.2588（4） A, b=6.8633（2） A and c=7.2667（4） A. The results show that the ε-VOPO4 nanosheets have a thickness of 200 nm and uniform crystallinity. Electrochemical characterization of the ε-VOPO4 monoclinic nanosheets reveals that they have good electrochemical properties at high current density, and deliver high initial capacity of 230.3 mA· h/g at a current density of 0.09 mA/cm2. Following the first charge cycle, reversible electrochemical lithium extraction/insertion at current density of 0.6 mA/cm2 affords a capacity retention rate of 73.6% （2.0？4.3 V window） that is stable for at least 1000 cycles.展开更多
Perovskite ZnTiO3 was prepared through a new method which contained a hydrothermal process for the preparation of titanate nanotubes and an ion-exchange process.The titanate nanotubes were inferred to be H2Ti3O7·...Perovskite ZnTiO3 was prepared through a new method which contained a hydrothermal process for the preparation of titanate nanotubes and an ion-exchange process.The titanate nanotubes were inferred to be H2Ti3O7·3H2O.X-ray diffraction（XRD）result revealed the presence of cubic perovskite phase of ZnTiO3.The unique chain-like morphology of ZnTiO3 was observed by scanning electron microscopy（SEM） and transmission electron microscopy（TEM）.UV-Vis diffusive reflection spectra of ZnTiO3indicated that the absorbance obviously increased in the visible light region.The degradation rate of methyl orange solution（15 mg/L）reached 95.3%over ZnTiO3（0.3 g/L） after 20 min xenon light irradiation,which was higher than that using the commercial catalyst P25 under the same reaction condition.The degradation kinetic results follow the first-order equation and the rate constant is 0.1020.展开更多
Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation rea...Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation reaction. The products were characterized by means of Fourier transform infrared spectrometry, ^13C NMR spectrometry and ^31p NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.展开更多
Y-β zeolite composites were hydrotherrnally synthesized by using high silica Y zeolite as the precursor and characterized by XRD, N2 adsorption, SEM and IR spectra of pyridine. The result showed that the N2 adsorptio...Y-β zeolite composites were hydrotherrnally synthesized by using high silica Y zeolite as the precursor and characterized by XRD, N2 adsorption, SEM and IR spectra of pyridine. The result showed that the N2 adsorption-desorption isotherm of the zeolite composites had a distinct hysteresis loop, and the SEM result showed that the zeolite composites had a different morphology from Y, β and the corresponding physical zeolite mixture. The acid catalytic performance of the zeolite composite catalysts was investigated in the hydrocracking and hydroisomerization of n-octane, and the results showed that the composite materials exhibited an excellent hydrocracking activity and good hydroisomerization performance. The yield of i-C4 over the zeolite composite catalyst was 4.45% higher than that on the corresponding zeolite mixture in the n-octane hydrocracking process at 553 K. The isomerization ability of n-octane over the composite catalyst was 3.6 fold that of the corresponding mixture at 503 K.展开更多
Hydroxyapatite （HA） nano-powder was synthesized via wet chemical technique in a used precipitation reaction, in which Ca（OH）2 and H3PO4 were used as precursors. Deionised water was used as a diluting media for the...Hydroxyapatite （HA） nano-powder was synthesized via wet chemical technique in a used precipitation reaction, in which Ca（OH）2 and H3PO4 were used as precursors. Deionised water was used as a diluting media for the reaction and ammonia was used to adjust the pH. The synthetic HA nano-powder has some medical applications such as a coating material in orthopaedic implants and in dental. HA powder has been studied at different temperatures from 100 to 800 ℃ to achieve the stoichiometric Ca/P ratio 1.667. The optimum temperature was found to be 600 ℃. Above this temperature, the HA powder decomposed to CaO. The crystallite size of HA powder was found to be in the range of 8.47-24.47 nm. The crystallographic properties were evaluated by X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X- ray spectroscopy and scanning electron microscopy. The results show that, high purity of nano-hydroxyapatite powders could be obtained at low temperatures, and the crystallinity, crystallite size and Ca/P ratio of the resulting nanoparticles were found to be dependent on the calcination temperature. When Ca/P ratio exceeded 1.75, formation of CaO phase was observed.展开更多
Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Thei...Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Their acidities were determined by pyridine probe on IR spectrography.展开更多
Using cetyltrimethylammonium bromide （CTAB） as the template agent, cerium nitrate as the cerium resource, yttrium nitrate as the yttrium resource, and ammonium carbonate as the precipitating agent, mesoporous CeO2 p...Using cetyltrimethylammonium bromide （CTAB） as the template agent, cerium nitrate as the cerium resource, yttrium nitrate as the yttrium resource, and ammonium carbonate as the precipitating agent, mesoporous CeO2 powders doped with different yttrium contents were successfully synthesized using a chemical precipitation method, under an alkalescent condition. Properties of the obtained samples were characterized and analyzed with X-ray diffraction （XRD）, energy dispersive analysis of X-rays （EDAX）, transmission electron microscopy （TEM）, infrared （IR） absorbance, and the BET method. For the prepared samples with 20% （molar ratio） Y-doped content, a BET specific surface area of 106. 6 m^2 · g^- 1, with an average pore size of3~27 nm were obtained. XRD patterns showed that the doped samples were with a cubic fluorite structure. TEM micrographs revealed that the doped samples showed a spherical morphology with a diameter ranging from 20 to 30 nm and a round pore shape. IR results indicated that the Ce-O-Ce vibration intensity decreased as the Y-doped content increased. N2 adsorption-desorption isotherms showed that the samples possessed typical mesopore characteristics. The average pore size of the samples decreased alter mesoporous CeO2 was doped with yttrium, and the average pore size decreased largely as the Y-doped content increased.展开更多
CdSe semiconductor nanocrystals capped by CdS were synthesized in the aqueous solution with 2 mercaptoethanol as the stabilizer. The CdS capping with a higher band gap than that of the core crystallite has successfu...CdSe semiconductor nanocrystals capped by CdS were synthesized in the aqueous solution with 2 mercaptoethanol as the stabilizer. The CdS capping with a higher band gap than that of the core crystallite has successfully eliminated the surface traps. Optical absorption and fluorescence emission spectra were used to probe the effect of CdS passivation on the electronic structure of the nanocrystals. The composite CdSe/CdS nanocrystals exhibit strong, narrow(FWHM≤40 nm) and stable band edge photoluminescence. X ray powder diffraction, transmission electron microscopy and X ray photoelectron spectroscopy were used to analyze the composite nanocrystals and determine their average size, size distribution, shape, internal structure and elemental composition.展开更多
A novel method to prepare mesoporous nano-zirconia was developed. Thesynthesis was carried out in the presence of PEO surfactants via a solid-state reaction. Thematerials exhibit a strong diffraction peak at low 2θ a...A novel method to prepare mesoporous nano-zirconia was developed. Thesynthesis was carried out in the presence of PEO surfactants via a solid-state reaction. Thematerials exhibit a strong diffraction peak at low 2θ angle and their nitrogenadsorption/desorption isotherms are typical of type IV with H1 hysteresis loops. The pore structureimaged by TEM can be described as wormhole domains. The tetragonal zirconia nanocrystals are uniformin size (around 1.5 nm) and their mesopores focus on around 4.6 nm. The zirconia nanocrystal growthis tentatively postulated to be the result of an aggregation mechanism. This study also revealsthat the PEO surfactants can interact with the Zr-O-Zr framework to reinforce the thermal stabilityof zirconia. The ratio of NaOH to ZrOCl_2, crystallization and calcination temperature play animportant role in the synthesis of mesoporous nano-zirconia.展开更多
The synthesis of Friedel＇s salt （FS： 3CaO·Al2O3·CaCl2·10H2O） by the reaction of calcium chloride with sodium aluminate was investigated. Factors affecting the preparation of Friedel＇s salt, such as...The synthesis of Friedel＇s salt （FS： 3CaO·Al2O3·CaCl2·10H2O） by the reaction of calcium chloride with sodium aluminate was investigated. Factors affecting the preparation of Friedel＇s salt, such as reaction temperature, initial concentration, titration speed, aging time and molar Ca/Al ratio were studied in detail. XRD, SEM images and particle size distribution show that the reaction temperature, aging time and molar Ca/Al ratio have significant effect on the composition, crystal morphology, and average particle size of the obtained samples. In addition, the initial CaCl2 concentration and NaAlO2 titration speed do not significantly influence the morphology and particle size distribution of Friedel＇s salt. With the optimization of the operating conditions, the crystals can grow up to a average size of about 28 μm, showing flat hexagonal （or pseudo- hexagonal） crystal morphology. Moreover, two potential mechanisms of Friedel＇s salt formation including adsorption mechanism and anion-exchange mechanism were discussed. In the adsorption mechanism, Friedel＇s salt forms due to the adsorption of the bulk C1- ions present in the solution into the interlayers of the principal layers, [Ca2Al（OH-）6·2H2O]＋, in order to balance the charge. In the anion-exchange mechanism, the freechloride ions bind with the AFro （a family of hydrated compounds found in cement） hydrates to form Friedel＇s salt by anion-exchange with the ions present in the interlayers of the principal layer, [Ca2Al（OH-）6. 2H2O]＋- OH-.展开更多
Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1...Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1H) NMR spectra and molar conductivity. The scavenging activity of genistein and five lanthanides complexes on the hydroxyl free radicals (OH·) was also investigated by spectrophotometric methods. The results show that the scavenging activity of the complexes is better than that of the ligand and their scavenging ability can be assembled in the following order: Sm>La>Dy>Eu>Tb>L.展开更多
The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate （CTriMATT） were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, ...The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate （CTriMATT） were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, X-ray diffraction （XRD）, Fourier transform infrared （FT-IR）, Ultraviolet visible （UV-Vis） spectra. The results showed that the as-synthesized CTriMATT had high purity and good crystallinity. The introduction of alkyl groups induced a shift of the stretching vibration band of W-S bond to lower wavenumber, while it had no influence on the position of WS4^2-. Thermogravimetric analysis （TG）, differential thermal analysis （DTA） and in situ XRD characterizations revealed that CTriMATT began to decompose at 423 K in nitrogen and was converted to WS2 eventually. In addition, the decomposition product of CTriMATT at 673 K in nitrogen was characterized by N2 adsorption （BET） and scanning electron microscopy （SEM）. The results demonstrated that WS2 with higher specific surface area, and pore volume could be obtained from the thermal decomposition of CTriMATT in nitrogen.展开更多
Carbon-based single-atom catalysts(SACs) with atomic sizes of active sites have become the promising candidates for a variety of catalytic systems because of their high atom utilization, and unique electronic structur...Carbon-based single-atom catalysts(SACs) with atomic sizes of active sites have become the promising candidates for a variety of catalytic systems because of their high atom utilization, and unique electronic structures. Different types of single-atom sites can be fabricated via multiple preparation strategies, which would demonstrate distinct different coordination configurations and electronic features, and ultimately affected the structure-catalysis relationship of SACs in targeted reactions. As a result, it is necessary to identify the active sites of SACs and understand the structure-catalysis relationship of SACs at the atomic scale. In this review, a variety of preparation strategies of carbon-based SACs were documented. Then, the recent development on versatile characterization techniques and computational achievements were summarized regarding in understanding the electronic and geometric characteristics of carbon-based SACs.Finally, major challenges and development directions concerning single-atom sites identification and advanced tools development are discussed to shed light on future research of carbon-based SACs.展开更多
The unsaturated quaternary ammonium salt diethyldiallylammonium chloride(DEDAAC) was synthesized in a two-step synthetic method. The influences of the adding method of raw materials and temperature on the yields of di...The unsaturated quaternary ammonium salt diethyldiallylammonium chloride(DEDAAC) was synthesized in a two-step synthetic method. The influences of the adding method of raw materials and temperature on the yields of diethylallylamine (DEAA), and drying and temperature on the synthesis of DEDAAC were investigated. The content of in-process product DEAA was determined by non-aqueous titration. The structure of product DEDAAC was identified with IR, 1 H NMR and elemental analysis. The results show that adding allyl chloride and sodium hydroxide alternately can increase the yield of DEAA and decrease by-products. In further synthesizing of DEDAAC from DEAA, the step of drying DEAA is very necessary. When DEAA is dried by solid sodium hydroxide, good columnar crystals with a high purity(mp 199.5-201.0 ℃) are obtained; when DEAA is undried or the content of water in DEAA is above 20%, only platelets with bad quality are obtained even without crystals. The suitable synthesis conditions for DEAA and DEDAAC are 35 ℃, 6 h and 40 ℃, 36 h, respectively, and their yields are 69.7% and 67.3%, respectively.展开更多
A montmorillonite inorgano-intercalation compound（MIIC） was synthesized by using a purified Na-exchanged bentonite（PNaB） as a matrix and Al-pillaring ion as an intercalating reagent under microwave irradiation.The...A montmorillonite inorgano-intercalation compound（MIIC） was synthesized by using a purified Na-exchanged bentonite（PNaB） as a matrix and Al-pillaring ion as an intercalating reagent under microwave irradiation.The synthesized products were characterized by X-ray diffraction（XRD）,^27Al magic angle sample-spinning nuclear magnetic resonance（^27Al MAS NMR）,specific surface area（BET） measurement,and adsorption density determination.The results show that,at 5% solid（PNaB） concentration and 7 minutes irradiation in a 130 W microwave oven,the basal spacing d（001） of the synthesized MIIC increases to 1.740 nm from the original 1.218 nm of PNaB.The MIIC has much higher adsorptive densities to F-and Cr^6＋ from aqueous solution than the PNaB.The adsorption isotherm of F-on the MIIC follows the Freundlich equation,and the increased adsorption is mainly due to the porous structure of the MIIC which created larger adsorption surfaces.The adsorption isotherm of Cr^6＋ on MIIC follows the Langmuir equation and the adsorption is mainly monolayer as a result of chemisorptions.展开更多
A novel conjugated polymer containing azobenzene and oxadiazole units was synthesized through multi-step synthesis. The structures and properties of monomer and polymer were characterized and evaluated with IR, ^1H NM...A novel conjugated polymer containing azobenzene and oxadiazole units was synthesized through multi-step synthesis. The structures and properties of monomer and polymer were characterized and evaluated with IR, ^1H NMR, UV, TGA and GPC, respectively. Polymer with long side chain of alkoxy shows good solubility, thermal stability and photoisomerization property.展开更多
文摘2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(4)H_(2)N)C_(6)H4NC(Ph)=NDipp]-,Dipp=2,6-iPr_(2)C_(6)H_(3))were investigated.The 1H NMR spectroscopy indicate that the reaction of ytrrium dialkyl complex with one equivalent of 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10) produce the mixture of ytrrium alkyl-amido complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))(CH_(2)SiMe3)](R=CH_(3),2a;R=Ph,2b)and bis(amido)complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))_(2)](R=CH_(3),3a;R=Ph,3b).The yttrium bridging imido complex[Y(L)(2-CH_(3)-1-N-o-C_(2)B_(10)H_(10))]_(2)(4a)was obtained by heating the mixture at 55℃for 12 h.Complex 3a was isolated and characterized by treating the yttrium dialkyl complex with two equivalents of 1a.The structures of complexes 3a and 4a were verified by single-crystal Xray diffraction.CCDC:2424136,3a;2424137,4a.
基金M.A.F.acknowledges the financing support by Universidad Nacional del Sur(Grant No.PGI 24/Q112 and Grant No.PICT 2021-I-A-00288)Agencia Nacional de Promoción Científica y Tecnológica(ANPCyT)(Grant No.PIP 2021-2023 GI 11220200100317CO).
文摘This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of uses.An overview of the current trends in nanoglass research connects them to the Sustainable Development Goals,highlighting the current relevance of this topic.The process of manufacturing nanoglasses is explained in depth,highlighting advanced approaches such as inert gas condensation and severe plastic deformation,among other techniques.The prime focus of this review is on analyzing the various dimensions of nanoglass materials,including their structural dynamics and electrical configurations,and how these features contribute to their exceptional thermal stability and mechanical strength.The magnetic characteristics of nanoglasses are examined,highlighting their potential for driving innovation across multiple industries.The primary emphasis is on the biological usefulness of nanoglasses,specifically examining their bioactivity and interaction with biological components,and emphasizing their growing use in nanoscale biomedical applications.With regard to the practical applications of nanoglasses,there are specific discussions of their contributions to biological evaluation,wound healing,catalysis,and environmental sustainability.There is an emphasis on the durability and resistance of nanoglasses in these contexts.The comprehensive overview of nanoglasses provided in this article highlights their significance as revolutionary materials in fields of science and technology.The potential of nanoglasses to contribute to a future that is more sustainable and health oriented is indicated.The article ends by discussing the future directions for nanoglass research and looks forward to the promising possibilities for further investigation and innovation.
基金supported by the Suranaree University of Technology(SUT)Center of Excellence(CoE)on Advanced Functional Materials(AFM),School of Physics,Suranaree University of Technology,Nakhon Ratchasima,Thailand,the External Grants and Scholarships for Graduate Students,Suranaree University of Technology,Nakhon Ratchasima,Thailand,and the Research Network on Nanotechnology(RNN),Suranaree University of Technology,Nakhon Ratchasima,Thailand.
文摘High-purity SiO_(2)nanoparticles(SNPs)play a crucial role in various electronic applications,such as semiconductors,solar cells,optical fibers,lenses,and insulating layers,given their purity and particle size,which significantly impact device efficiency.This study fo-cuses on the synthesis and characterization of pure SNPs through the chemical etching of greater club rush.White powder SNPs were pre-pared using HCl etching,and their thermal behaviors were analyzed via thermogravimetric analysis/differential scanning calorimetry.Structural properties were investigated using X-ray fluorescence,scanning electron microscopy,and transmission electron microscopy.X-ray absorption near-edge structure was employed to assess the oxidation state of the SNPs.The morphology of the SNPs after the first etching was amorphous,with sizes ranging from 50 to 100 nm,which increased to 50-200 nm after the second etching.Despite this size variation,the SNPs maintained a high purity level of 99.8wt%SiO_(2),comparable with industry standards.Notably,the second etching with 0.1-M HCl significantly enhanced the purity level,achieving 99.8wt%SiO_(2)mass.Furthermore,HCl etching facilitated the formation of SiO_(2)in the Si^(4+)oxidation state,akin to industrial SNPs.These findings underscore the critical role of HCl etching in synthesizing high-purity SNPs,with potential applications in advanced electronic devices.
基金Funded by the Program(BG2021)of High-end Foreign Experts of The State Administration of Foreign Experts Affairs(SAFEA)the Young Talent Project of Hubei Provincial Department of Education,China(No.Q20201108)。
文摘High molecular weight poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate)copolyesters(PBSIF-x)were synthesized via melt-polycondensation of 2,5-furandicarboxylic acid(FDCA),with varying ratios of isosorbide(ISB)and 1,4-butylene glycol(BDO)catalyzed by antimony trioxide(Sb_(2)O_(3)).The PBSIF-x structures were investigated using FTIR and~1H NMR,while the GPC analysis exhibited the copolyesters molecular weights with number average molecular mass(M_n)in the range of 11079-15153 g/mol.The DSC results show that PBSIF-x copolyesters have a single glass-transition temperature(T_(g))(77.45-110.96℃),increasing with the increase in ISB content,while TGA analysis demonstrates excellent thermal stability up to 320℃.From the thermal result,properties of PBSIF-x copolyesters are found to be within the interval of their parent homologues poly(butylene 2,5-furandicarboxylate)(PBF)and poly(isosorbide 2,5-furandicarboxylate)(PIF),which confirms the aromatic/aliphatic blending within the polymer matrix for enhanced polymer stability and performance.
基金Projects(51172065,51404097,51504083,U1404613)supported by the National Natural Science Foundation of ChinaProject(16A150009)supported by the Key Scientific Research Project for Higher Education of Henan Province,China+2 种基金Project(16A150009)supported by the Natural Science Foundation of Henan Province(General Program)ChinaProject(166115)supported by the Postdoctoral Science Foundation of Henan Province,China
文摘Vanadium （III） phosphate monoclinic VPO4·H2O was synthesized hydrothermally. The ε-VOPO4 nanosheets, formed by the oxidative de-intercalation of protons from monoclinic VPO4·H2O, can reversibly react with more than 1 mol lithium atoms in two steps. Crystal XRD analysis revealed that the structure of the ε-VOPO4 nanosheets is monoclinic with lattice parameters of α=7.2588（4） A, b=6.8633（2） A and c=7.2667（4） A. The results show that the ε-VOPO4 nanosheets have a thickness of 200 nm and uniform crystallinity. Electrochemical characterization of the ε-VOPO4 monoclinic nanosheets reveals that they have good electrochemical properties at high current density, and deliver high initial capacity of 230.3 mA· h/g at a current density of 0.09 mA/cm2. Following the first charge cycle, reversible electrochemical lithium extraction/insertion at current density of 0.6 mA/cm2 affords a capacity retention rate of 73.6% （2.0？4.3 V window） that is stable for at least 1000 cycles.
基金Projects(50702020,81171461)supported by the National Natural Science Foundation of ChinaProject(11JJ4013)supported by Natural Science Foundation of Hunan Province,ChinaProject supported by the Young Teacher Promotion Fund by Hunan University,China
文摘Perovskite ZnTiO3 was prepared through a new method which contained a hydrothermal process for the preparation of titanate nanotubes and an ion-exchange process.The titanate nanotubes were inferred to be H2Ti3O7·3H2O.X-ray diffraction（XRD）result revealed the presence of cubic perovskite phase of ZnTiO3.The unique chain-like morphology of ZnTiO3 was observed by scanning electron microscopy（SEM） and transmission electron microscopy（TEM）.UV-Vis diffusive reflection spectra of ZnTiO3indicated that the absorbance obviously increased in the visible light region.The degradation rate of methyl orange solution（15 mg/L）reached 95.3%over ZnTiO3（0.3 g/L） after 20 min xenon light irradiation,which was higher than that using the commercial catalyst P25 under the same reaction condition.The degradation kinetic results follow the first-order equation and the rate constant is 0.1020.
文摘Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation reaction. The products were characterized by means of Fourier transform infrared spectrometry, ^13C NMR spectrometry and ^31p NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.
文摘Y-β zeolite composites were hydrotherrnally synthesized by using high silica Y zeolite as the precursor and characterized by XRD, N2 adsorption, SEM and IR spectra of pyridine. The result showed that the N2 adsorption-desorption isotherm of the zeolite composites had a distinct hysteresis loop, and the SEM result showed that the zeolite composites had a different morphology from Y, β and the corresponding physical zeolite mixture. The acid catalytic performance of the zeolite composite catalysts was investigated in the hydrocracking and hydroisomerization of n-octane, and the results showed that the composite materials exhibited an excellent hydrocracking activity and good hydroisomerization performance. The yield of i-C4 over the zeolite composite catalyst was 4.45% higher than that on the corresponding zeolite mixture in the n-octane hydrocracking process at 553 K. The isomerization ability of n-octane over the composite catalyst was 3.6 fold that of the corresponding mixture at 503 K.
文摘Hydroxyapatite （HA） nano-powder was synthesized via wet chemical technique in a used precipitation reaction, in which Ca（OH）2 and H3PO4 were used as precursors. Deionised water was used as a diluting media for the reaction and ammonia was used to adjust the pH. The synthetic HA nano-powder has some medical applications such as a coating material in orthopaedic implants and in dental. HA powder has been studied at different temperatures from 100 to 800 ℃ to achieve the stoichiometric Ca/P ratio 1.667. The optimum temperature was found to be 600 ℃. Above this temperature, the HA powder decomposed to CaO. The crystallite size of HA powder was found to be in the range of 8.47-24.47 nm. The crystallographic properties were evaluated by X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X- ray spectroscopy and scanning electron microscopy. The results show that, high purity of nano-hydroxyapatite powders could be obtained at low temperatures, and the crystallinity, crystallite size and Ca/P ratio of the resulting nanoparticles were found to be dependent on the calcination temperature. When Ca/P ratio exceeded 1.75, formation of CaO phase was observed.
基金the‘973’Program of the Chinese Ministry of Science and Technology(G-2000048002).
文摘Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Their acidities were determined by pyridine probe on IR spectrography.
基金Project supported by the International Cooperation of Science and Technology Ministry PRC (2005DFBA028)the National Natural Science Foundation of China (59925412)
文摘Using cetyltrimethylammonium bromide （CTAB） as the template agent, cerium nitrate as the cerium resource, yttrium nitrate as the yttrium resource, and ammonium carbonate as the precipitating agent, mesoporous CeO2 powders doped with different yttrium contents were successfully synthesized using a chemical precipitation method, under an alkalescent condition. Properties of the obtained samples were characterized and analyzed with X-ray diffraction （XRD）, energy dispersive analysis of X-rays （EDAX）, transmission electron microscopy （TEM）, infrared （IR） absorbance, and the BET method. For the prepared samples with 20% （molar ratio） Y-doped content, a BET specific surface area of 106. 6 m^2 · g^- 1, with an average pore size of3~27 nm were obtained. XRD patterns showed that the doped samples were with a cubic fluorite structure. TEM micrographs revealed that the doped samples showed a spherical morphology with a diameter ranging from 20 to 30 nm and a round pore shape. IR results indicated that the Ce-O-Ce vibration intensity decreased as the Y-doped content increased. N2 adsorption-desorption isotherms showed that the samples possessed typical mesopore characteristics. The average pore size of the samples decreased alter mesoporous CeO2 was doped with yttrium, and the average pore size decreased largely as the Y-doped content increased.
基金Supported by the National NaturalScience Foundation of China( No. 2 0 0 75 0 0 9)
文摘CdSe semiconductor nanocrystals capped by CdS were synthesized in the aqueous solution with 2 mercaptoethanol as the stabilizer. The CdS capping with a higher band gap than that of the core crystallite has successfully eliminated the surface traps. Optical absorption and fluorescence emission spectra were used to probe the effect of CdS passivation on the electronic structure of the nanocrystals. The composite CdSe/CdS nanocrystals exhibit strong, narrow(FWHM≤40 nm) and stable band edge photoluminescence. X ray powder diffraction, transmission electron microscopy and X ray photoelectron spectroscopy were used to analyze the composite nanocrystals and determine their average size, size distribution, shape, internal structure and elemental composition.
文摘A novel method to prepare mesoporous nano-zirconia was developed. Thesynthesis was carried out in the presence of PEO surfactants via a solid-state reaction. Thematerials exhibit a strong diffraction peak at low 2θ angle and their nitrogenadsorption/desorption isotherms are typical of type IV with H1 hysteresis loops. The pore structureimaged by TEM can be described as wormhole domains. The tetragonal zirconia nanocrystals are uniformin size (around 1.5 nm) and their mesopores focus on around 4.6 nm. The zirconia nanocrystal growthis tentatively postulated to be the result of an aggregation mechanism. This study also revealsthat the PEO surfactants can interact with the Zr-O-Zr framework to reinforce the thermal stabilityof zirconia. The ratio of NaOH to ZrOCl_2, crystallization and calcination temperature play animportant role in the synthesis of mesoporous nano-zirconia.
基金Funded by International Science&Technology Cooperation Program of China(No.2013DFB70220)the National Natural Science Foundation of China(No.21076212)the Natural Science Foundation of Guizhou Province of China(No.[2014]2003)
文摘The synthesis of Friedel＇s salt （FS： 3CaO·Al2O3·CaCl2·10H2O） by the reaction of calcium chloride with sodium aluminate was investigated. Factors affecting the preparation of Friedel＇s salt, such as reaction temperature, initial concentration, titration speed, aging time and molar Ca/Al ratio were studied in detail. XRD, SEM images and particle size distribution show that the reaction temperature, aging time and molar Ca/Al ratio have significant effect on the composition, crystal morphology, and average particle size of the obtained samples. In addition, the initial CaCl2 concentration and NaAlO2 titration speed do not significantly influence the morphology and particle size distribution of Friedel＇s salt. With the optimization of the operating conditions, the crystals can grow up to a average size of about 28 μm, showing flat hexagonal （or pseudo- hexagonal） crystal morphology. Moreover, two potential mechanisms of Friedel＇s salt formation including adsorption mechanism and anion-exchange mechanism were discussed. In the adsorption mechanism, Friedel＇s salt forms due to the adsorption of the bulk C1- ions present in the solution into the interlayers of the principal layers, [Ca2Al（OH-）6·2H2O]＋, in order to balance the charge. In the anion-exchange mechanism, the freechloride ions bind with the AFro （a family of hydrated compounds found in cement） hydrates to form Friedel＇s salt by anion-exchange with the ions present in the interlayers of the principal layer, [Ca2Al（OH-）6. 2H2O]＋- OH-.
文摘Six genistein lanthanide complexes, LnL_2 (OAc)·nH_2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()~1H) NMR spectra and molar conductivity. The scavenging activity of genistein and five lanthanides complexes on the hydroxyl free radicals (OH·) was also investigated by spectrophotometric methods. The results show that the scavenging activity of the complexes is better than that of the ligand and their scavenging ability can be assembled in the following order: Sm>La>Dy>Eu>Tb>L.
基金This work is sponsored by National Key Fundamental Research Development Plan ("973" Plan, No.2004CB217807)the China National Petroleum Corporation (No. B04A50502)
文摘The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate （CTriMATT） were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, X-ray diffraction （XRD）, Fourier transform infrared （FT-IR）, Ultraviolet visible （UV-Vis） spectra. The results showed that the as-synthesized CTriMATT had high purity and good crystallinity. The introduction of alkyl groups induced a shift of the stretching vibration band of W-S bond to lower wavenumber, while it had no influence on the position of WS4^2-. Thermogravimetric analysis （TG）, differential thermal analysis （DTA） and in situ XRD characterizations revealed that CTriMATT began to decompose at 423 K in nitrogen and was converted to WS2 eventually. In addition, the decomposition product of CTriMATT at 673 K in nitrogen was characterized by N2 adsorption （BET） and scanning electron microscopy （SEM）. The results demonstrated that WS2 with higher specific surface area, and pore volume could be obtained from the thermal decomposition of CTriMATT in nitrogen.
基金supported by Tai Shan Scholar Foundation (No.ts201511003)financial support from the Australian Research Council via Discovery Projects (Nos.DE210100253 and DP190103548)。
文摘Carbon-based single-atom catalysts(SACs) with atomic sizes of active sites have become the promising candidates for a variety of catalytic systems because of their high atom utilization, and unique electronic structures. Different types of single-atom sites can be fabricated via multiple preparation strategies, which would demonstrate distinct different coordination configurations and electronic features, and ultimately affected the structure-catalysis relationship of SACs in targeted reactions. As a result, it is necessary to identify the active sites of SACs and understand the structure-catalysis relationship of SACs at the atomic scale. In this review, a variety of preparation strategies of carbon-based SACs were documented. Then, the recent development on versatile characterization techniques and computational achievements were summarized regarding in understanding the electronic and geometric characteristics of carbon-based SACs.Finally, major challenges and development directions concerning single-atom sites identification and advanced tools development are discussed to shed light on future research of carbon-based SACs.
文摘The unsaturated quaternary ammonium salt diethyldiallylammonium chloride(DEDAAC) was synthesized in a two-step synthetic method. The influences of the adding method of raw materials and temperature on the yields of diethylallylamine (DEAA), and drying and temperature on the synthesis of DEDAAC were investigated. The content of in-process product DEAA was determined by non-aqueous titration. The structure of product DEDAAC was identified with IR, 1 H NMR and elemental analysis. The results show that adding allyl chloride and sodium hydroxide alternately can increase the yield of DEAA and decrease by-products. In further synthesizing of DEDAAC from DEAA, the step of drying DEAA is very necessary. When DEAA is dried by solid sodium hydroxide, good columnar crystals with a high purity(mp 199.5-201.0 ℃) are obtained; when DEAA is undried or the content of water in DEAA is above 20%, only platelets with bad quality are obtained even without crystals. The suitable synthesis conditions for DEAA and DEDAAC are 35 ℃, 6 h and 40 ℃, 36 h, respectively, and their yields are 69.7% and 67.3%, respectively.
基金Funded by Specialized Research Project for the Doctoral Program of Higher Education (No. 20020497005)Funded by Specialized Research Project for Unversity Key Teacher by theMinistry of Education,China
文摘A montmorillonite inorgano-intercalation compound（MIIC） was synthesized by using a purified Na-exchanged bentonite（PNaB） as a matrix and Al-pillaring ion as an intercalating reagent under microwave irradiation.The synthesized products were characterized by X-ray diffraction（XRD）,^27Al magic angle sample-spinning nuclear magnetic resonance（^27Al MAS NMR）,specific surface area（BET） measurement,and adsorption density determination.The results show that,at 5% solid（PNaB） concentration and 7 minutes irradiation in a 130 W microwave oven,the basal spacing d（001） of the synthesized MIIC increases to 1.740 nm from the original 1.218 nm of PNaB.The MIIC has much higher adsorptive densities to F-and Cr^6＋ from aqueous solution than the PNaB.The adsorption isotherm of F-on the MIIC follows the Freundlich equation,and the increased adsorption is mainly due to the porous structure of the MIIC which created larger adsorption surfaces.The adsorption isotherm of Cr^6＋ on MIIC follows the Langmuir equation and the adsorption is mainly monolayer as a result of chemisorptions.
基金supported by the National Natural Science Foundation of China(No.20573049).
文摘A novel conjugated polymer containing azobenzene and oxadiazole units was synthesized through multi-step synthesis. The structures and properties of monomer and polymer were characterized and evaluated with IR, ^1H NMR, UV, TGA and GPC, respectively. Polymer with long side chain of alkoxy shows good solubility, thermal stability and photoisomerization property.
