The thermal degradation of poly（arylene sulfide sulfone）/N-methylpyrrolidone （PASS/NMP） crystal solvate was studied by thermogravimetric analysis （TGA） and was compared with pure PASS in order to determine the w...The thermal degradation of poly（arylene sulfide sulfone）/N-methylpyrrolidone （PASS/NMP） crystal solvate was studied by thermogravimetric analysis （TGA） and was compared with pure PASS in order to determine the way in which the formation of the crystal solvate affected the thermal properties of the polymer. The activation energy of the solid state process was determined using Kissinger＇s method, which does not require knowledge of the reaction mechanism （RM）, to be 174.18 kJ/mol which was lower than that for pure PASS （E = 214 kJ/mol）. The study of master curves together with interpretation of integral methods, allows confirmation that the thermal degradation mechanism for PASS in the crystal solvate system is a decelerated Rn type, which is a solid-state process based on a phase boundary controlled reaction, in the conversion range considered. Whereas, the pure PASS follows a decelerated Dn thermodegradation mechanism in the same conversion range.展开更多
A novel compound 5-（p-tolyl）-4-[2-（2,4-dichlorophenoxy）acetamido]-1,2,4-tria zole- 3-thione 2a has been synthesized by the reaction of 5-（p-tolyl）-4-amino-1,2,4-triazole-3-thione 1 with 2-（2,4-dich/orophenoxy）...A novel compound 5-（p-tolyl）-4-[2-（2,4-dichlorophenoxy）acetamido]-1,2,4-tria zole- 3-thione 2a has been synthesized by the reaction of 5-（p-tolyl）-4-amino-1,2,4-triazole-3-thione 1 with 2-（2,4-dich/orophenoxy）acetyl ch/oride. Interestingly, the title compound 2 was obtained when 2a crystallizes from a mixed solution of petroleum ether and ethyl acetate, and it has been characterized by elemental analysis, IR, ^1H NMR spectra and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 9.780（5）, b = 10.876（6）, c = 11.615（6） /A, a = 104.822（7）, β= 94.105（6）, ）, = 94.305（6）°, V= 1185.7（11）/A3, Z = 2,μ = 0.397 mm^-1, Mr= 497.39, Dx= 1.393 g/cm^3, F（000） = 516, S = 1.097, the final R = 0.0730 and wR = 0.2133 for 4111 unique reflections （Rint = 0.0525） with 3212 observed ones. The dihedral angles made by the triazole ring with the methyl- and chloro-substituted benzene rings are 43.5（7） and 50.2（9）°, respectively. Some intra- and intermolecular hydrogen bonds together with C-H…π interactions existing in the lattice stabilize the crystal structure.展开更多
Norfloxacin methanol solvate （ 1 -ethyl-6-fluoro- 1,4-dihydro-4-oxo-7-（ 1 -piperazinyl）-3- quinoline carboxylic acid methanol solvate） has been prepared. The crystal and molecular structures of the title compound,...Norfloxacin methanol solvate （ 1 -ethyl-6-fluoro- 1,4-dihydro-4-oxo-7-（ 1 -piperazinyl）-3- quinoline carboxylic acid methanol solvate） has been prepared. The crystal and molecular structures of the title compound, C16H18FN3O3·CH3OH·H2O, were determined by X-ray diffraction method. The compound crystallizes in monoclinic, space group P21/c with a = 7.8660（16）, b = 22.525 （5）, c = 10.253（2）A, β= 108.31°, Mr = 369.39, V = 1724.7（6）A^3, Z = 4, Dc= 1.423 g/cm^3, F（000） = 784, R = 0.0557 and wR = 0.1224. The TGA analysis indicates that it decomposes completely at 723.75℃.展开更多
In this paper, the gelation mechanism of erythromycin ethylsuccinate(EES) during crystallization is investigated for the first time. The generated semisolid gel-like phase exhibited a 3D fibrillar network morphology a...In this paper, the gelation mechanism of erythromycin ethylsuccinate(EES) during crystallization is investigated for the first time. The generated semisolid gel-like phase exhibited a 3D fibrillar network morphology and the typical rheological properties of gels. The fibers inside the gel-like phase were confirmed to be new types of EES solvates using powder X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, and gas chromatography. The gelation and crystallization regions in EES-1-propanol solid–liquid phase diagram were determined. Analyses of solvent parameters showed that moderate solvent polarity may promote EES gelation. Fourier transform infrared spectra, nuclear magnetic resonance spectra, and scanning electron microscopy analyses indicated that through intermolecular hydrogen bonds, EES and solvent molecules assembled into fibers via crystallographic mismatch branching growth. The fibers intertwined into a 3D network microstructure and formed a gel-like phase, completely immobilizing the solution.展开更多
Crystal engineering is employed widely in developing metal-free room-temperature phosphorescence(RTP)materials,buttheweakresponsiveness inrigid stateand poor selectivity during crystallization limit the research of RT...Crystal engineering is employed widely in developing metal-free room-temperature phosphorescence(RTP)materials,buttheweakresponsiveness inrigid stateand poor selectivity during crystallization limit the research of RTP materials with specific recognition properties.Herein,based on multicomponent crystallization and the deformation of phosphor,we have developed a galactose-functionalized polyhydric compound(BHB)with a twisted 4-bromobiphenyl structure,to realize methanol selectively activated“off–on”RTP system.Methanol molecules selectively formed solvate with BHB and rigidified the crystal structure by enriching intermolecular noncovalent interactions.Meanwhile,the distortion of the biphenyl group facilitated the intersystem crossing process effectively,alongside the heavy-atom effect from the bromo substitute,thereby,activating the RTP of BHB.Thus our current research approach realizes RTPmaterials with selective recognition function by controlling multiple noncovalent interactions such as hydrogen and halogen bonding of molecular systems with structurally distorted phosphors.展开更多
Clindamycin phosphate （CP）, an antibacterial agent, has been reported to form several solid-state forms. The crystal structures of two CP solvates, a dimethyl sulfoxide （DMSO） solvate and a methanol/water solvate ...Clindamycin phosphate （CP）, an antibacterial agent, has been reported to form several solid-state forms. The crystal structures of two CP solvates, a dimethyl sulfoxide （DMSO） solvate and a methanol/water solvate （solvate V）, have been determined by single crystal X-ray diffraction. The properties and transformations of these forms were characterized by powder X-ray diffraction, Single-crystal X-ray diffraction, differential scanning calorimetry, thermo gravimetric analysis, hot-stage microscopy, and dynamic vapor sorption. Very different hydrogen bonding networks exist among the host-host and host-solvent molecules in the two crystal structures, resulting in different moisture stabilities. The thermal stabilities of the two solvates upon heating and desolvation were also studied. When the temperature was above the boiling point of methanol, solvate V converted to a polymorphic phase after a one step desolvation process, whereas the desolvation temperature of the DMSO solvate was below the boiling point of DMSO. At the relative humidity above 43%, the DMSO solvate transformed to a hydrate at 25 ℃. In contrast, solvate V did not transform at any of the humidities studied.展开更多
Omeprazole sodium(OMS), a typical non-hydrogen bond donors API, is only available in solvates so far, including monohydrate, ethanol solvate and methanol solvate. The methanol solvate was found for the first time. Sol...Omeprazole sodium(OMS), a typical non-hydrogen bond donors API, is only available in solvates so far, including monohydrate, ethanol solvate and methanol solvate. The methanol solvate was found for the first time. Solvate transformation thermodynamics of OMS was studied in this paper. First, the ternary phase diagrams forming two solvates for OMS in binary solvent mixtures including methanol + water, ethanol + water, and methanol+ ethanol were measured at temperature ranging of T =(278.15 to 313.15) K under atmospheric pressure. Further, the standard equilibrium constants of the solvate transformation reactions were evaluated according to the chemical reaction isothermal equation. The standard molar Gibbs free energy, the standard molar enthalpy, and the standard molar entropy of solvate transformation reactions were then calculated based on van't Hoff equation. Moreover, the thermodynamic stability of the OMS solvate was analyzed based on phase diagram. The results are of great importance to develop a crystallization process for manufacturing OMS solvate, and could be helpful to other solvate transformation research.展开更多
Ordered amorphous carbon clusters(OACC)transformed from m-xylene solvated C_(60)(C_(60)·m-xylene)are known as the first crystalline material constructed from amorphous building blocks and have attracted a lot of ...Ordered amorphous carbon clusters(OACC)transformed from m-xylene solvated C_(60)(C_(60)·m-xylene)are known as the first crystalline material constructed from amorphous building blocks and have attracted a lot of attention.The formation mechanism and physical properties of this material are of great importance for the design of more materials with such structural characteristics.In this article,the transport and structural properties of C_(60)·m-xylene are systematically investigated under pressure using impedance spectroscopy,four-probe resistance measurements,and Raman spectroscopy.It is found that C_(60)·mxylene is an insulator at ambient pressure.The resistance decreases sharply starting at the pressure around 8 GPa due to the pressure-induced dimerization of C_(60)verified by the Raman study.The presence of solvent hinders further polymerization of C_(60)under higher pressures.The temperature-dependence of resistance exhibits a semiconducting characteristic at>8-26.9 GPa,and is well described by Mott's three-dimensional variable-range hopping model(3D-VRH),indicating an insulating-tosemiconducting transition accompanied with pressure-induced dimerization.The resistance and hopping energy are both found to decrease monotonically with pressure and reach the minimum near 24 GPa.Above the pressure,resistance and hopping energy values start to rise,suggesting a transition to another semiconducting state,which is attributed to the pressure-induced formation of OACC.The conductivity shows a large hysteresis during decompression from higher than 24 GPa,confirming a different transport behavior of the sample with retained fullerenes versus OACC.The findings of our study suggest that the transport property of fullerene is tunable by introducing solvates and further enhance our understanding of the OACC.展开更多
All-solid-state lithium metal batteries(ASSLMBs)that incorporate solid electrolyte(SE)and lithium metal anode suggest considerable potential in addressing the security concerns and energy density limitation of convent...All-solid-state lithium metal batteries(ASSLMBs)that incorporate solid electrolyte(SE)and lithium metal anode suggest considerable potential in addressing the security concerns and energy density limitation of conventional lithium-ion batteries(LIBs).However,the practical application of ASSLMBs is always restricted by the interfacial instability of lithium metal anode/electrolyte and inevitable lithium dendrites propagation in SE.Herein,a solvate ionic liquid is adopted to modify the interface stability of lithium metal anode/electrolyte and inhibit the growth of lithium dendrites via an in-situ formation of a robust solid electrolyte interphase(SEI)on the surface of lithium metal anode.Consequently,the ASSLMBs assembled with Li_(6)PS_(5)Cl(LPSCl)electrolyte,lithium metal anode that protected by robust SEI layer,and LiNbO_(3)@NCM622 cathode exhibit high initial capacity of 126.5 mAh·g^(−1)and improved cycling stability with a capacity retention of 80.3%over 60 cycles at 0.1 C.This work helps to provide a facile route for the design of robust SEI in the application of ASSLMBs.展开更多
The co-crystallization of quercetin(Qur)with a flexible molecule 4-(4-pyridinyldisulfanyl)pyridine(DPDS)in different solvents and conditions was investigated,yielded five multi-component crystalline phases and charact...The co-crystallization of quercetin(Qur)with a flexible molecule 4-(4-pyridinyldisulfanyl)pyridine(DPDS)in different solvents and conditions was investigated,yielded five multi-component crystalline phases and characterized with X-ray diffractions and thermal analysis.Although the crystal system of Qur-DPDSMe OH and Qur-DPDS-Dioxane is the same,the desolvation results revealed that Qur-DPDS-Me OH transformed to Qur-DPDS when Me OH solvent molecules escape from the lattice,while Qur-DPDS-Dioxane transformed to Qur-DPDS-II through a similar process,which is same with Qur-DPDS-THF.These two cocrystal polymorphs Qur-DPDS and Qur-DPDS-II obey an enantiotropic relationship.Moreover,the formation of cocrystal solvates improves the packing efficiency of crystals.Crystal structure analysis showed that hydrogen bonds and conformations of the corresponding parent molecules play a major role in molecular assembly and crystal packing patterns,thus bring different physicochemical properties.Finally,the fluorescence spectra and quantum-chemical calculations were carried out to explore the difference in the optical-physical properties.展开更多
Tautomers are structural isomers that readily interconvert and may exhibit diff erent properties.The eff ect of solvent on tautomeric equilibria in solution has been a subject of some research.Tautomer solvate is less...Tautomers are structural isomers that readily interconvert and may exhibit diff erent properties.The eff ect of solvent on tautomeric equilibria in solution has been a subject of some research.Tautomer solvate is less common,and the role of solvent in the crystallization of tautomer solvate remains an interesting topic.In this work,we used 6-amino-1,3-dimethyl-5-nitrosouracil(NAU)as the tautomeric model material,which can present in nitrone–enamine form(Tautomer A)or oxime–imine form(Tautomer B).A solvate with NAU/DMSO ratio of 1:1 was discovered and characterized using single/powder X-ray diff raction and thermogravimetry.The crystal structure of NAU·DMSO was determined for the fi rst time,where only Tautomer A was formed in the tautomeric crystal.Quantum chemical calculation and molecular dynamics simulation were conducted to determine the tautomeric form in DMSO solution.Electrostatic potential analysis,radial distribution function analysis,and binding energy suggested possible DMSO–NAU interaction modes and stable tautomer complexes in solution.Tautomer A-containing complexes were found to dominate in solution,as verifi ed by comparing predicted and experimental 1 H NMR spectra.Findings reveal that the hydrogen bonding between DMSO and NAU is similar in solution and in NAU–DMSO solvate crystal,which helps preserve the form of Tautomer A during solvate crystallization.展开更多
The desolvation of erythromycin acetone solvate was investigated under non-isothermal conditions by a thermogravimetric analyzer. This paper emphasized the kinetic analysis of non-isothermal TG-DTA data by Achar metho...The desolvation of erythromycin acetone solvate was investigated under non-isothermal conditions by a thermogravimetric analyzer. This paper emphasized the kinetic analysis of non-isothermal TG-DTA data by Achar method and Coats-Redfern method to fit various solid-state reaction models, and to achieve kinetic parameters of desolvation. The mechanism of thermal desolvation was evaluated using the kinetic compensation effect. The results show that kinetics of desolvation of erythromycin acetone solvate was compatible with the mechanism of a two-dimensional diffusion controlled and was best expressed by Valensi equation. Corresponding to the integral method and the differential method, the activation energy of desolvation of erythromycin acetone solvate was estimated to be 51.26—57.11 kJ/mol, and the pre-exponential factor was 8.077×106 s-1—4.326×107 s-1, respectively.展开更多
基金supported by the 863 program of China(No.2007AA 03Z561)
文摘The thermal degradation of poly（arylene sulfide sulfone）/N-methylpyrrolidone （PASS/NMP） crystal solvate was studied by thermogravimetric analysis （TGA） and was compared with pure PASS in order to determine the way in which the formation of the crystal solvate affected the thermal properties of the polymer. The activation energy of the solid state process was determined using Kissinger＇s method, which does not require knowledge of the reaction mechanism （RM）, to be 174.18 kJ/mol which was lower than that for pure PASS （E = 214 kJ/mol）. The study of master curves together with interpretation of integral methods, allows confirmation that the thermal degradation mechanism for PASS in the crystal solvate system is a decelerated Rn type, which is a solid-state process based on a phase boundary controlled reaction, in the conversion range considered. Whereas, the pure PASS follows a decelerated Dn thermodegradation mechanism in the same conversion range.
基金supported by the NN S F of China (No. 20672073)Shanghai Leading Academic Discipline (No. T0402)
文摘A novel compound 5-（p-tolyl）-4-[2-（2,4-dichlorophenoxy）acetamido]-1,2,4-tria zole- 3-thione 2a has been synthesized by the reaction of 5-（p-tolyl）-4-amino-1,2,4-triazole-3-thione 1 with 2-（2,4-dich/orophenoxy）acetyl ch/oride. Interestingly, the title compound 2 was obtained when 2a crystallizes from a mixed solution of petroleum ether and ethyl acetate, and it has been characterized by elemental analysis, IR, ^1H NMR spectra and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 9.780（5）, b = 10.876（6）, c = 11.615（6） /A, a = 104.822（7）, β= 94.105（6）, ）, = 94.305（6）°, V= 1185.7（11）/A3, Z = 2,μ = 0.397 mm^-1, Mr= 497.39, Dx= 1.393 g/cm^3, F（000） = 516, S = 1.097, the final R = 0.0730 and wR = 0.2133 for 4111 unique reflections （Rint = 0.0525） with 3212 observed ones. The dihedral angles made by the triazole ring with the methyl- and chloro-substituted benzene rings are 43.5（7） and 50.2（9）°, respectively. Some intra- and intermolecular hydrogen bonds together with C-H…π interactions existing in the lattice stabilize the crystal structure.
基金This work was supported by the Social Development Foundation of Jiangsu Province (No:BS2002043)
文摘Norfloxacin methanol solvate （ 1 -ethyl-6-fluoro- 1,4-dihydro-4-oxo-7-（ 1 -piperazinyl）-3- quinoline carboxylic acid methanol solvate） has been prepared. The crystal and molecular structures of the title compound, C16H18FN3O3·CH3OH·H2O, were determined by X-ray diffraction method. The compound crystallizes in monoclinic, space group P21/c with a = 7.8660（16）, b = 22.525 （5）, c = 10.253（2）A, β= 108.31°, Mr = 369.39, V = 1724.7（6）A^3, Z = 4, Dc= 1.423 g/cm^3, F（000） = 784, R = 0.0557 and wR = 0.1224. The TGA analysis indicates that it decomposes completely at 723.75℃.
基金supported by the National Natural Science Foundation of China(Nos.21576187,21776203)
文摘In this paper, the gelation mechanism of erythromycin ethylsuccinate(EES) during crystallization is investigated for the first time. The generated semisolid gel-like phase exhibited a 3D fibrillar network morphology and the typical rheological properties of gels. The fibers inside the gel-like phase were confirmed to be new types of EES solvates using powder X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, and gas chromatography. The gelation and crystallization regions in EES-1-propanol solid–liquid phase diagram were determined. Analyses of solvent parameters showed that moderate solvent polarity may promote EES gelation. Fourier transform infrared spectra, nuclear magnetic resonance spectra, and scanning electron microscopy analyses indicated that through intermolecular hydrogen bonds, EES and solvent molecules assembled into fibers via crystallographic mismatch branching growth. The fibers intertwined into a 3D network microstructure and formed a gel-like phase, completely immobilizing the solution.
基金supported financially by NSFC(21788102,21722603,and 21871083)“Shu Guang’project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation(19SG26)+2 种基金the Innovation Program of Shanghai Municipal Education Commission(2017-01-07-00-02-E00010)Shanghai Municipal Science and Technology Major Project(grant no.2018SHZDZX03)Fundamental Research Funds for the Central Universities.
文摘Crystal engineering is employed widely in developing metal-free room-temperature phosphorescence(RTP)materials,buttheweakresponsiveness inrigid stateand poor selectivity during crystallization limit the research of RTP materials with specific recognition properties.Herein,based on multicomponent crystallization and the deformation of phosphor,we have developed a galactose-functionalized polyhydric compound(BHB)with a twisted 4-bromobiphenyl structure,to realize methanol selectively activated“off–on”RTP system.Methanol molecules selectively formed solvate with BHB and rigidified the crystal structure by enriching intermolecular noncovalent interactions.Meanwhile,the distortion of the biphenyl group facilitated the intersystem crossing process effectively,alongside the heavy-atom effect from the bromo substitute,thereby,activating the RTP of BHB.Thus our current research approach realizes RTPmaterials with selective recognition function by controlling multiple noncovalent interactions such as hydrogen and halogen bonding of molecular systems with structurally distorted phosphors.
基金The authors are grateful for the financial support from the National Natural Science Foundation of China （Grant Nos. 81361140344 and 2136164）, the National High Technology Research and Development Program of China （2015AA021002） and the Major National Scientific Instrument Development Project （No.21537812）.
文摘Clindamycin phosphate （CP）, an antibacterial agent, has been reported to form several solid-state forms. The crystal structures of two CP solvates, a dimethyl sulfoxide （DMSO） solvate and a methanol/water solvate （solvate V）, have been determined by single crystal X-ray diffraction. The properties and transformations of these forms were characterized by powder X-ray diffraction, Single-crystal X-ray diffraction, differential scanning calorimetry, thermo gravimetric analysis, hot-stage microscopy, and dynamic vapor sorption. Very different hydrogen bonding networks exist among the host-host and host-solvent molecules in the two crystal structures, resulting in different moisture stabilities. The thermal stabilities of the two solvates upon heating and desolvation were also studied. When the temperature was above the boiling point of methanol, solvate V converted to a polymorphic phase after a one step desolvation process, whereas the desolvation temperature of the DMSO solvate was below the boiling point of DMSO. At the relative humidity above 43%, the DMSO solvate transformed to a hydrate at 25 ℃. In contrast, solvate V did not transform at any of the humidities studied.
基金Supported by the National Natural Science Foundation of China(21776203 and 21576187)the Tianjin Municipal Natural Science Foundation(18JCYBJC21100)
文摘Omeprazole sodium(OMS), a typical non-hydrogen bond donors API, is only available in solvates so far, including monohydrate, ethanol solvate and methanol solvate. The methanol solvate was found for the first time. Solvate transformation thermodynamics of OMS was studied in this paper. First, the ternary phase diagrams forming two solvates for OMS in binary solvent mixtures including methanol + water, ethanol + water, and methanol+ ethanol were measured at temperature ranging of T =(278.15 to 313.15) K under atmospheric pressure. Further, the standard equilibrium constants of the solvate transformation reactions were evaluated according to the chemical reaction isothermal equation. The standard molar Gibbs free energy, the standard molar enthalpy, and the standard molar entropy of solvate transformation reactions were then calculated based on van't Hoff equation. Moreover, the thermodynamic stability of the OMS solvate was analyzed based on phase diagram. The results are of great importance to develop a crystallization process for manufacturing OMS solvate, and could be helpful to other solvate transformation research.
基金This work was supported by the National Natural Science Foundation of China(Nos.52090020 and 11874076)National Research Foundation of Korea(Nos.2016K1A4A3914691 and 2018R1D1A1B07049811).
文摘Ordered amorphous carbon clusters(OACC)transformed from m-xylene solvated C_(60)(C_(60)·m-xylene)are known as the first crystalline material constructed from amorphous building blocks and have attracted a lot of attention.The formation mechanism and physical properties of this material are of great importance for the design of more materials with such structural characteristics.In this article,the transport and structural properties of C_(60)·m-xylene are systematically investigated under pressure using impedance spectroscopy,four-probe resistance measurements,and Raman spectroscopy.It is found that C_(60)·mxylene is an insulator at ambient pressure.The resistance decreases sharply starting at the pressure around 8 GPa due to the pressure-induced dimerization of C_(60)verified by the Raman study.The presence of solvent hinders further polymerization of C_(60)under higher pressures.The temperature-dependence of resistance exhibits a semiconducting characteristic at>8-26.9 GPa,and is well described by Mott's three-dimensional variable-range hopping model(3D-VRH),indicating an insulating-tosemiconducting transition accompanied with pressure-induced dimerization.The resistance and hopping energy are both found to decrease monotonically with pressure and reach the minimum near 24 GPa.Above the pressure,resistance and hopping energy values start to rise,suggesting a transition to another semiconducting state,which is attributed to the pressure-induced formation of OACC.The conductivity shows a large hysteresis during decompression from higher than 24 GPa,confirming a different transport behavior of the sample with retained fullerenes versus OACC.The findings of our study suggest that the transport property of fullerene is tunable by introducing solvates and further enhance our understanding of the OACC.
基金supported by the National Natural Science Foundation of China(No.U21A2080)Shanxi key research and development program(No.202102060301011)Key scientific research projects of colleges and universities in Henan Province(No.23A430044).
文摘All-solid-state lithium metal batteries(ASSLMBs)that incorporate solid electrolyte(SE)and lithium metal anode suggest considerable potential in addressing the security concerns and energy density limitation of conventional lithium-ion batteries(LIBs).However,the practical application of ASSLMBs is always restricted by the interfacial instability of lithium metal anode/electrolyte and inevitable lithium dendrites propagation in SE.Herein,a solvate ionic liquid is adopted to modify the interface stability of lithium metal anode/electrolyte and inhibit the growth of lithium dendrites via an in-situ formation of a robust solid electrolyte interphase(SEI)on the surface of lithium metal anode.Consequently,the ASSLMBs assembled with Li_(6)PS_(5)Cl(LPSCl)electrolyte,lithium metal anode that protected by robust SEI layer,and LiNbO_(3)@NCM622 cathode exhibit high initial capacity of 126.5 mAh·g^(−1)and improved cycling stability with a capacity retention of 80.3%over 60 cycles at 0.1 C.This work helps to provide a facile route for the design of robust SEI in the application of ASSLMBs.
基金financially supported by the National Natural Science Foundation of China(Nos.22178254 and 21621004)。
文摘The co-crystallization of quercetin(Qur)with a flexible molecule 4-(4-pyridinyldisulfanyl)pyridine(DPDS)in different solvents and conditions was investigated,yielded five multi-component crystalline phases and characterized with X-ray diffractions and thermal analysis.Although the crystal system of Qur-DPDSMe OH and Qur-DPDS-Dioxane is the same,the desolvation results revealed that Qur-DPDS-Me OH transformed to Qur-DPDS when Me OH solvent molecules escape from the lattice,while Qur-DPDS-Dioxane transformed to Qur-DPDS-II through a similar process,which is same with Qur-DPDS-THF.These two cocrystal polymorphs Qur-DPDS and Qur-DPDS-II obey an enantiotropic relationship.Moreover,the formation of cocrystal solvates improves the packing efficiency of crystals.Crystal structure analysis showed that hydrogen bonds and conformations of the corresponding parent molecules play a major role in molecular assembly and crystal packing patterns,thus bring different physicochemical properties.Finally,the fluorescence spectra and quantum-chemical calculations were carried out to explore the difference in the optical-physical properties.
基金The authors thank the fi nancial support from the National Natural Science Foundation of China(No.21776204).
文摘Tautomers are structural isomers that readily interconvert and may exhibit diff erent properties.The eff ect of solvent on tautomeric equilibria in solution has been a subject of some research.Tautomer solvate is less common,and the role of solvent in the crystallization of tautomer solvate remains an interesting topic.In this work,we used 6-amino-1,3-dimethyl-5-nitrosouracil(NAU)as the tautomeric model material,which can present in nitrone–enamine form(Tautomer A)or oxime–imine form(Tautomer B).A solvate with NAU/DMSO ratio of 1:1 was discovered and characterized using single/powder X-ray diff raction and thermogravimetry.The crystal structure of NAU·DMSO was determined for the fi rst time,where only Tautomer A was formed in the tautomeric crystal.Quantum chemical calculation and molecular dynamics simulation were conducted to determine the tautomeric form in DMSO solution.Electrostatic potential analysis,radial distribution function analysis,and binding energy suggested possible DMSO–NAU interaction modes and stable tautomer complexes in solution.Tautomer A-containing complexes were found to dominate in solution,as verifi ed by comparing predicted and experimental 1 H NMR spectra.Findings reveal that the hydrogen bonding between DMSO and NAU is similar in solution and in NAU–DMSO solvate crystal,which helps preserve the form of Tautomer A during solvate crystallization.
文摘The desolvation of erythromycin acetone solvate was investigated under non-isothermal conditions by a thermogravimetric analyzer. This paper emphasized the kinetic analysis of non-isothermal TG-DTA data by Achar method and Coats-Redfern method to fit various solid-state reaction models, and to achieve kinetic parameters of desolvation. The mechanism of thermal desolvation was evaluated using the kinetic compensation effect. The results show that kinetics of desolvation of erythromycin acetone solvate was compatible with the mechanism of a two-dimensional diffusion controlled and was best expressed by Valensi equation. Corresponding to the integral method and the differential method, the activation energy of desolvation of erythromycin acetone solvate was estimated to be 51.26—57.11 kJ/mol, and the pre-exponential factor was 8.077×106 s-1—4.326×107 s-1, respectively.
