This manuscript reports results of combined computational chemistry and batch adsorption investigation of insensitive munition compounds, 2,4-dinitroanisole(DNAN), triaminotrinitrobenzene(TATB), 1,1-diamino-2,2-di...This manuscript reports results of combined computational chemistry and batch adsorption investigation of insensitive munition compounds, 2,4-dinitroanisole(DNAN), triaminotrinitrobenzene(TATB), 1,1-diamino-2,2-dinitroethene(FOX-7) and nitroguanidine(NQ), and traditional munition compound 2,4,6-trinitrotoluene(TNT) on the surfaces of cellulose, cellulose triacetate, chitin and chitosan biopolymers. Cellulose,cellulose triacetate, chitin and chitosan were modeled as trimeric form of the linear chain of4 C1 chair conformation of β-D-glucopyranos, its triacetate form, β-N-acetylglucosamine and D-glucosamine, respectively, in the 1 ? 4 linkage. Geometries were optimized at the M062 X functional level of the density functional theory(DFT) using the 6-31 G(d,p) basis set in the gas phase and in the bulk water solution using the conductor-like polarizable continuum model(CPCM) approach. The nature of potential energy surfaces of the optimized geometries were ascertained through the harmonic vibrational frequency analysis. The basis set superposition error(BSSE) corrected interaction energies were obtained using the 6-311 G(d,p)basis set at the same theoretical level. The computed BSSE in the gas phase was used to correct interaction energy in the bulk water solution. Computed and experimental results regarding the ability of considered surfaces in adsorbing the insensitive munitions compounds are discussed.展开更多
Cellulose triacetate membranes doped with organo-phosphoric carriers (2-ethylhexyl) phosphoric acid noted (D2EHPA) or trioctyl phosphine oxide noted (TOPO) as fixed carriers and 2-nitro phenyl octyl ether noted (NPOE)...Cellulose triacetate membranes doped with organo-phosphoric carriers (2-ethylhexyl) phosphoric acid noted (D2EHPA) or trioctyl phosphine oxide noted (TOPO) as fixed carriers and 2-nitro phenyl octyl ether noted (NPOE) or tris ethylhexyl phosphate noted (TEHP) as a plasticizers have been prepared and applied for investigation to the facilitated transport of Pb(II) and Cd(II) ions from aqueous nitrate source phase. The membranes Polymer-Plasticizer- Carrier were characterised using chemical techniques as well as Fourier Transform Infra-Red (FTIR), X-ray Diffraction and Scanning electron microscopy (SEM). A study of the transport across a polymer inclusion membrane has shown that the lead or cadmium transport efficiency was increased using D2EHPA as carrier at pH 1-2.展开更多
Zirconia-loaded sulfuric acid (SO2-/ZrO2) catalysts were prepared by impregnation method, molded by punch tablet machine and characterized by X-ray diffraction. SO4^2-/ZrO2 catalyst was used to obtain glycerol triac...Zirconia-loaded sulfuric acid (SO2-/ZrO2) catalysts were prepared by impregnation method, molded by punch tablet machine and characterized by X-ray diffraction. SO4^2-/ZrO2 catalyst was used to obtain glycerol triacetate (GTA) directly from glycerin. The effect of some factors, such as different temperatures of calcination and catalysts molded or not, on the reusable times of catalysts and the yield of GTA were investigated. The optimum reaction conditions were shown as follows: the reaction temperature was 403 K; the reaction time continued for 8 h; the amount of molded catalysts was 5 wt% of glycerin and the molar ratio of glycerin to acetic acid was 1 : 8. The yield of GTA was 97.93% under the optimum condition.展开更多
Several organic polymers and sol-gel derived porous silica were investigated as cladding material of a fused silica optical fi ber as well as a solid phase microextraction (SPME) material in an eff ort to develop an e...Several organic polymers and sol-gel derived porous silica were investigated as cladding material of a fused silica optical fi ber as well as a solid phase microextraction (SPME) material in an eff ort to develop an evanescent wave optical fi ber chemical sensor (EW-OFCS) for detecting acetylsalicylic acid (ASA) in aqueous sample solutions.A dip-coating method was adopted for coating a polymer on the fi ber core surface of a bent optical fi ber probe (BOFP) as a cladding/SPME membrane.Among the polymers investigated,it was found that cellulose triacetate (CTA) can function as a SPME material for concentrating ASA from aqueous sample solution into CTA membrane coated on BOFP surface.The ASA concentrated into the CTA membrane was detected by passing a light beam through the BOFP and detecting the fi ber optic EW absorption signal at ASA’s intrinsic peak absorption wavelength (310 nm).No chemical reaction was involved in the developed sensor and no chemical reagent is needed in using the sensor for detecting ASA in an aqueous sample solution.The sensor response is reversible because SPME is a reversible process.This SPME-EW-OFCS achieved a detection limit of 0.72μg/mL for detecting ASA in aqueous sample solutions.The sensor has been used for analyzing ASA in pharmaceutical Aspirin products,and obtained analytical results agree well with a conventional UV/Vis absorption spectrometric method.展开更多
Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical in...Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical interactions of additives with the perovskite lattice,band structure,and charge carriers.Herein,how additives of cellulose triacetate(CTA)improve the photovoltaic performance and stability of perovskite solar cells(PSCs)is shown.These improvements are found to stem from the formation of hydrogen bonds between CTA molecules and organic cations.The Kelvin probe force microscopy results show that contact potential difference variation under dark and light conditions increases from 79.68 to 141.24 mV by doping CTA,indicating enhanced separation of electron-hole pairs in perovskite.The piezoresponse force microscopy(PFM)tests indicate that CTA additives reduce the PFM amplitude by approximately 50 pm under dark and light conditions and inhibit flipping from antiferroelectric domains to ferroelectric domains.Moreover,the CTA additives regulate the charge distribution within the PbI6 octahedron and bind organic ions through hydrogen bonding,forming a compact film structure.These findings not only improve the long-term stability of organic-inorganic hybrid perovskites(OIHPs),but also pave the way for developing novel strategies for large-scale PSCs.展开更多
Manganese triacetate was introduced as a new reagent for radical cyclization of substituted aminothioureas. Bis-(1,2,4-triazolyl)-3-disulfides were generated in 10 min under microwave irradiation.
文摘This manuscript reports results of combined computational chemistry and batch adsorption investigation of insensitive munition compounds, 2,4-dinitroanisole(DNAN), triaminotrinitrobenzene(TATB), 1,1-diamino-2,2-dinitroethene(FOX-7) and nitroguanidine(NQ), and traditional munition compound 2,4,6-trinitrotoluene(TNT) on the surfaces of cellulose, cellulose triacetate, chitin and chitosan biopolymers. Cellulose,cellulose triacetate, chitin and chitosan were modeled as trimeric form of the linear chain of4 C1 chair conformation of β-D-glucopyranos, its triacetate form, β-N-acetylglucosamine and D-glucosamine, respectively, in the 1 ? 4 linkage. Geometries were optimized at the M062 X functional level of the density functional theory(DFT) using the 6-31 G(d,p) basis set in the gas phase and in the bulk water solution using the conductor-like polarizable continuum model(CPCM) approach. The nature of potential energy surfaces of the optimized geometries were ascertained through the harmonic vibrational frequency analysis. The basis set superposition error(BSSE) corrected interaction energies were obtained using the 6-311 G(d,p)basis set at the same theoretical level. The computed BSSE in the gas phase was used to correct interaction energy in the bulk water solution. Computed and experimental results regarding the ability of considered surfaces in adsorbing the insensitive munitions compounds are discussed.
文摘Cellulose triacetate membranes doped with organo-phosphoric carriers (2-ethylhexyl) phosphoric acid noted (D2EHPA) or trioctyl phosphine oxide noted (TOPO) as fixed carriers and 2-nitro phenyl octyl ether noted (NPOE) or tris ethylhexyl phosphate noted (TEHP) as a plasticizers have been prepared and applied for investigation to the facilitated transport of Pb(II) and Cd(II) ions from aqueous nitrate source phase. The membranes Polymer-Plasticizer- Carrier were characterised using chemical techniques as well as Fourier Transform Infra-Red (FTIR), X-ray Diffraction and Scanning electron microscopy (SEM). A study of the transport across a polymer inclusion membrane has shown that the lead or cadmium transport efficiency was increased using D2EHPA as carrier at pH 1-2.
基金supported by the National High Technology Research and Development Program of China (No. 2009AA03Z222 and No. 2009AA05Z437)the "Six Talents Pinnacle Program" of Jiangsu Province of China (No. 2008028)
文摘Zirconia-loaded sulfuric acid (SO2-/ZrO2) catalysts were prepared by impregnation method, molded by punch tablet machine and characterized by X-ray diffraction. SO4^2-/ZrO2 catalyst was used to obtain glycerol triacetate (GTA) directly from glycerin. The effect of some factors, such as different temperatures of calcination and catalysts molded or not, on the reusable times of catalysts and the yield of GTA were investigated. The optimum reaction conditions were shown as follows: the reaction temperature was 403 K; the reaction time continued for 8 h; the amount of molded catalysts was 5 wt% of glycerin and the molar ratio of glycerin to acetic acid was 1 : 8. The yield of GTA was 97.93% under the optimum condition.
基金West Texas A&M University Killgore Research Grant。
文摘Several organic polymers and sol-gel derived porous silica were investigated as cladding material of a fused silica optical fi ber as well as a solid phase microextraction (SPME) material in an eff ort to develop an evanescent wave optical fi ber chemical sensor (EW-OFCS) for detecting acetylsalicylic acid (ASA) in aqueous sample solutions.A dip-coating method was adopted for coating a polymer on the fi ber core surface of a bent optical fi ber probe (BOFP) as a cladding/SPME membrane.Among the polymers investigated,it was found that cellulose triacetate (CTA) can function as a SPME material for concentrating ASA from aqueous sample solution into CTA membrane coated on BOFP surface.The ASA concentrated into the CTA membrane was detected by passing a light beam through the BOFP and detecting the fi ber optic EW absorption signal at ASA’s intrinsic peak absorption wavelength (310 nm).No chemical reaction was involved in the developed sensor and no chemical reagent is needed in using the sensor for detecting ASA in an aqueous sample solution.The sensor response is reversible because SPME is a reversible process.This SPME-EW-OFCS achieved a detection limit of 0.72μg/mL for detecting ASA in aqueous sample solutions.The sensor has been used for analyzing ASA in pharmaceutical Aspirin products,and obtained analytical results agree well with a conventional UV/Vis absorption spectrometric method.
基金supported by the National Natural Science Foundation of China(No.U2130128)Yanzhao Young Scientist Project from Natural Science Foundation of Hebei Province(Nos.B2023205040)+4 种基金Basic Research Cooperation Special Foundation of Beijing-Tianjin-Hebei Region(Nos.H2022205047,22JCZXJC00060 and E3B33911DF)Hebei Administration for Market Supervision Science and Technology Project List(No.2023ZC03)the Innovation Capability Improvement Plan Project of Hebei Province(No.22567604H)Ph.D.Scientific Research Start-up Fund of Hebei Normal University(No.L2023B18)College Student’s Innovation and Entrepreneurship Training Plan Program(No.S202410094046).
文摘Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical interactions of additives with the perovskite lattice,band structure,and charge carriers.Herein,how additives of cellulose triacetate(CTA)improve the photovoltaic performance and stability of perovskite solar cells(PSCs)is shown.These improvements are found to stem from the formation of hydrogen bonds between CTA molecules and organic cations.The Kelvin probe force microscopy results show that contact potential difference variation under dark and light conditions increases from 79.68 to 141.24 mV by doping CTA,indicating enhanced separation of electron-hole pairs in perovskite.The piezoresponse force microscopy(PFM)tests indicate that CTA additives reduce the PFM amplitude by approximately 50 pm under dark and light conditions and inhibit flipping from antiferroelectric domains to ferroelectric domains.Moreover,the CTA additives regulate the charge distribution within the PbI6 octahedron and bind organic ions through hydrogen bonding,forming a compact film structure.These findings not only improve the long-term stability of organic-inorganic hybrid perovskites(OIHPs),but also pave the way for developing novel strategies for large-scale PSCs.
基金Project supported by the Key Laboratory of 0rganic Synthesis of Jiangsu Province (No. JSK016) and the Natural Science Foundation of University, Anhui Province (No. 2006KJ156B).
文摘Manganese triacetate was introduced as a new reagent for radical cyclization of substituted aminothioureas. Bis-(1,2,4-triazolyl)-3-disulfides were generated in 10 min under microwave irradiation.