The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceu...The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceutical formulations.In this work,a developed machine-learning model efficiently predicts the solubility of APIs in polymers by learning the phase equilibrium principle and using a few molecular descriptors.Under the few-shot learning framework,thermodynamic theory(perturbed-chain statistical associating fluid theory)was used for data augmentation,and computational chemistry was applied for molecular descriptors'screening.The results showed that the developed machine-learning model can predict the API-polymer phase diagram accurately,broaden the solubility data of APIs in polymers,and reproduce the relationship between API solubility and the interaction mechanisms between API and polymer successfully,which provided efficient guidance for the development of pharmaceutical formulations.展开更多
The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive ut...The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future.展开更多
A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline...A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous structure.The adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic performance.Moreover,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical calculation.Considering the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.展开更多
Tissue engineering has become a promising strategy for repairing damaged cartilage and bone tissue. Among the scaffolds for tissue-engineering applications, injectable hydrogels have demonstrated great potential for u...Tissue engineering has become a promising strategy for repairing damaged cartilage and bone tissue. Among the scaffolds for tissue-engineering applications, injectable hydrogels have demonstrated great potential for use as three-dimensional cell culture scaffolds in cartilage and bone tissue engineering, owing to their high water content, similarity to the natural extracellular matrix(ECM), porous framework for cell transplantation and proliferation, minimal invasive properties, and ability to match irregular defects. In this review, we describe the selection of appropriate biomaterials and fabrication methods to prepare novel injectable hydrogels for cartilage and bone tissue engineering. In addition, the biology of cartilage and the bony ECM is also summarized. Finally, future perspectives for injectable hydrogels in cartilage and bone tissue engineering are discussed.展开更多
In order to solve the serious leaching problem of supported heteropoly acid catalysts in polar reaction media,12-molybdophosphoric acid encapsulated in the supercage of Cs+-exchanged Y zeolite was prepared by the &quo...In order to solve the serious leaching problem of supported heteropoly acid catalysts in polar reaction media,12-molybdophosphoric acid encapsulated in the supercage of Cs+-exchanged Y zeolite was prepared by the "ship in the bottle" synthesis.The influence of ion-exchange conditions and the synthesis parameters on the encapsulation of PMo12 were investigated.The obtained solid sample was characterized by X-ray diffraction(XRD),31P magic angle spin nuclear magnetic resonance(MAS NMR) and Fourier Transform Infrared Spectroscopy(FT-IR),and its catalytic activity in the esterification of acetic acid and n-butanol was tested.The ion-exchange time,concentration of aqueous Cs+ solution,pH value,and amount of Mo added in the synthesis mixture were revealed to influence the encapsulation very remarkably.Under the optimal conditions,12-molybdophosphoric acid could be successfully encapsulated in the supercage of CsY zeolite,and the samples showed considerable catalytic activity and excellent reusability in the esterification reaction.展开更多
Ce0.8Sm0.2O1.9(SDC) nanopowders were synthesized by an acrylamide polymerization process.The XRD results showed that SDC powders prepared at 700 °C possessed a cubic fluorite structure.Transmission electron micro...Ce0.8Sm0.2O1.9(SDC) nanopowders were synthesized by an acrylamide polymerization process.The XRD results showed that SDC powders prepared at 700 °C possessed a cubic fluorite structure.Transmission electron microscopy(TEM) indicated that the particle sizes of powders were in the range of 10-15 nm.A 98.3% of theoretical density was obtained when the SDC pellets were sintered at 1350 °C for 5 h,indicating that the powders had good sinterability.The conductivity of the sintered SDC ceramics was 0.019 S/cm at 6...展开更多
A new phenoxyacetamide derivative, methyl 2-((4-(2-(2-methylphenoxy)acetyl)pi- perazin-1-yl)methyl)benzoate (C22H26N2O4, M, = 382.45), has been synthesized and characterized by 1H NMR, 13C NMR, H RMS and sin...A new phenoxyacetamide derivative, methyl 2-((4-(2-(2-methylphenoxy)acetyl)pi- perazin-1-yl)methyl)benzoate (C22H26N2O4, M, = 382.45), has been synthesized and characterized by 1H NMR, 13C NMR, H RMS and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P21c with a = 11.145(2), b = 13.667(3), c = 13.998(3) A, β= 112.01(3)°, V= 1976.8(7)A3, Z = 4, Dc = 1.285 g/cm3, F(000) = 816, g = 0.089 mml, MoKa radiation (λ= 0.71073 A), the final R = 0.0602 and wR = 0.1533 for 2343 observed reflections with I 〉 20(I). Intramolecular C-H……O interactions as well as intermolecular C-H……O hydrogen bonds help to stabilize the crystal structure. The preliminary bioassay results show that the title compound exhibits potent neuroprotective activity.展开更多
Dexmedetomidine and its novel salt have been synthesized and characterized by single-crystal XRD and TGA/DSG. Components of the crystalline phase have also been investigated in terms of their corresponding Hirshfeld s...Dexmedetomidine and its novel salt have been synthesized and characterized by single-crystal XRD and TGA/DSG. Components of the crystalline phase have also been investigated in terms of their corresponding Hirshfeld surface. In the crystal lattice, a three-dimensional hydrogen-bonded network is observed. In this work, the salt strategy has been applied successfully to dexmedetomidine. One important parameter, i.e. stability, has also been significantly improved, which proves to be an important factor for solid dosage formulation. Furthermore, DSC/TGA analysis indicates that the salt maintains its crystallinity up to 300℃, suggesting a higher stability of the salt compared to pure dexmedetomidine.展开更多
A novel Cd(Ⅱ) coordination polymer, [CdCI(Hpc)H2O]n (1, H2pc = 1H-pyrazole-3- carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-...A novel Cd(Ⅱ) coordination polymer, [CdCI(Hpc)H2O]n (1, H2pc = 1H-pyrazole-3- carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-Vis spectrum, elemental analysis, single-crystal X-ray diffraction, as well as thermal analysis. Compound 1 crystallizes in monoclinic, P21/n space group with α = 7.0304(3), b = 10.3047(3), c = 10.6446(4) A, β= 107.174(4)°, F = 736.78(5) A^3, Z = 4, C4HsCdClN2O3, Mr = 276.95, Dc = 2.497 g/cm%3, F(000) = 528.0,μ= 3.281 mm^-1, R = 0.0169 and wR = 0.0387. The central metals adopt distorted octahedral geometry. Carboxyl groups of the ligand connect Cd(Ⅱ) into a one-dimensional chain, which further constructs a two-dimensional network by halogen bridging. Such two-dimensional structures are finally connected into a three-dimensional supramolecular architecture due to the hydrogen bonds and intermolecular π…π interactions. In addition, complex 1 has high thermal stability.展开更多
Current formulation development strongly relies on trial-and-error experiments in the laboratory by pharmaceutical scientists,which is time-consuming,high cost and waste materials.This research aims to integrate vario...Current formulation development strongly relies on trial-and-error experiments in the laboratory by pharmaceutical scientists,which is time-consuming,high cost and waste materials.This research aims to integrate various computational tools,including machine learning,molecular dynamic simulation and physiologically based absorption modeling(PBAM),to enhance andrographolide(AG)/cyclodextrins(CDs)formulation design.The light GBM prediction model we built before was utilized to predict AG/CDs inclusion's binding free energy.AG/γ-CD inclusion complexes showed the strongest binding affinity,which was experimentally validated by the phase solubility study.The molecular dynamic simulation was used to investigate the inclusion mechanism between AG andγ-CD,which was experimentally characterized by DSC,FTIR and NMR techniques.PBAM was applied to simulate the in vivo behavior of the formulations,which were validated by cell and animal experiments.Cell experiments revealed that the presence of D-α-Tocopherol polyethylene glycol succinate(TPGS)significantly increased the intracellular uptake of AG in MDCKMDR1 cells and the absorptive transport of AG in MDCK-MDR1 monolayers.The relative bioavailability of the AG-CD-TPGS ternary system in rats was increased to 2.6-fold and 1.59-fold compared with crude AG and commercial dropping pills,respectively.In conclusion,this is the first time to integrate various computational tools to develop a new AG-CD-TPGS ternary formulation with significant improvement of aqueous solubility,dissolution rate and bioavailability.The integrated computational tool is a novel and robust methodology to facilitate pharmaceutical formulation design.展开更多
The crystal structure of the new cinnamide derivative(E)-1-(4-(4-chlorobenzyl)piperazin-1-yl)-3-(benzo[d][1,3]dioxol-5-yl)prop-2-en-1-one(C(21)H(21)ClN2O3, Mr = 384.85) was determined by single-crystal X...The crystal structure of the new cinnamide derivative(E)-1-(4-(4-chlorobenzyl)piperazin-1-yl)-3-(benzo[d][1,3]dioxol-5-yl)prop-2-en-1-one(C(21)H(21)ClN2O3, Mr = 384.85) was determined by single-crystal X-ray diffraction method. Compound 5 crystallizes in the monoclinic system, space group P21/c with a = 11.762(2), b = 15.279(3), c = 11.865(2) , β = 116.57(3)°, V = 1907.1(7) 3, Z = 4, Dc = 1.340 g/cm3, F(000) = 808, μ = 0.224 mm-1, Mo Kα radiation(λ = 0.71073 ), the final R = 0.0565 and w R = 0.1479 for 2318 observed reflections with I 〉 2σ(I). Intramolecular C(9)–H(9A)···O(1) interactions as well as intermolecular C(16)–H(16A)···O(1) hydrogen bonds help to stabilize the crystal structure. The bioassay results indicated that the title compound displayed promising neuroprotection in vitro and in vivo, and suppressed apoptosis of glutamate-induced PC12 cells.展开更多
Since 2-aminonicotinic acid is a zwitterionic molecule,the salt or co-crystal strategy was used for the precipitation under identical conditions and obtained two novel salts: salt 1 with 2:1:2 stoichiometry of 2-am...Since 2-aminonicotinic acid is a zwitterionic molecule,the salt or co-crystal strategy was used for the precipitation under identical conditions and obtained two novel salts: salt 1 with 2:1:2 stoichiometry of 2-aminonicotinic acid:perchloric acid:H2O and salt 2 with 2:1:3 stoichiometry of 2-aminonicotinic acid:sulfuric acid:H2O. Their crystal structures were characterized by single-crystal X-ray diffraction,differential scanning calorimetry(DSC) and thermogravimetric analyses(TGA). The structure determination shows that two salts are both primarily stabilized by the strong N–H…O hydrogen bonding interaction between 2-aminonicotinic acid and its corresponding acids. Constituents of the salt-crystalline phase were also investigated in terms of Hirshfeld surfaces. In the crystal lattice,a three-dimensional hydrogen-bonded network is observed,including the formation of a two-dimensional molecular scaffolding motif. Hirshfeld surfaces and fingerprint plots of two salts show that the structures are stabilized by H…H,O–H…O and C–O…π intermolecular interactions.展开更多
The matrix polymer PTBCHNB bearing o-nitrobenzyl group was successfully synthesized by copolymerization of tertiary-butyl methacrylate(TBMA), cyclohexyl methacrylate(CHMA) and o-nitrobenzyl methacrylate(NBMA) via reve...The matrix polymer PTBCHNB bearing o-nitrobenzyl group was successfully synthesized by copolymerization of tertiary-butyl methacrylate(TBMA), cyclohexyl methacrylate(CHMA) and o-nitrobenzyl methacrylate(NBMA) via reversible addition fragmentation chain transfer(RAFT) polymerization method. PTBCHNB was characterized by FTIR, 1HNMR, GPC and DSC. After UV irradiation, the o-nitrobenzyl groups of PTBCHNB were photocleaved and the resulting carboxyl groups were highly alkali soluble, and PTBCHNB was converted to PCHIBMA bearing carboxyl groups. So, the matrix polymer could be etched by mild alkali solution with no requirements of photoacid generators and other diverse additives. The photocleavable behaviors of PTBCHNB were determined by FTIR, 1H NMR and TGA analysis. The resist formulated with PTBCHNB and cast in THF solution showed square pattern of 10 μm×10 μm using a mercury-xenon lamp in a contact printing mode and tetramethyl-ammonium hydroxide aqueous solution as a developer.展开更多
ZnO is introduced as an alternative to TiO2 in dye sensitized solar cells (DSSCs) due to its band gap similar to TiO2, higher electron mobility, and flexible procedures of preparations. Several samples of ZnO films ...ZnO is introduced as an alternative to TiO2 in dye sensitized solar cells (DSSCs) due to its band gap similar to TiO2, higher electron mobility, and flexible procedures of preparations. Several samples of ZnO films are prepared with the hydrothermal synthesis method and the sol-gel technique, respectively. These ZnO films were assembled as photoanodes in DSSCs using N3 dye as the sensitizer. The ZnO-based cells prepared by the hydrothermal synthesis show typical current source characteristics, whose fill factor (FF) is 0.44 and photo-to-electric power conversion efficiency is 0.34%. On the other hand, all the samples prepared with the sol-gel technique show accompanied source characteristics with relatively higher power conversion efficiencies (1%) but a lower FF (0.26). X-ray diffraction (XRD) and atomic force microscopy (AFM) measurements indicate that the sol-gel samples have small particles sizes. Therefore, sol-gel samples could adsorb more dye molecules to generate high conversion efficiencies. At the same time, more grain boundaries make it more possible for injected electrons to recombine with the oxidized electrolyte. Hydrothermal samples have bigger grains, so they show poor conversion efficiency and relatively high FF.展开更多
A newly synthesized 1,3,4-oxadiazole derivatives have been studied using a femtosecond Ti:sapphire laser system. The series molecules present strong three-photon absorption and frequency upeonversion fluorescence at ...A newly synthesized 1,3,4-oxadiazole derivatives have been studied using a femtosecond Ti:sapphire laser system. The series molecules present strong three-photon absorption and frequency upeonversion fluorescence at wavelengths from 1205 nm to 1575 nm. Furthermore, there is no proportional relationship between three-photon absorption cross sections and the chemical structure transformation from monomer, dimer to trimer. Effective charge-transfer distance by π-conjugation bonds may be the contributing factor. In the experimental design, the far-field intensity distribution of femtosecond laser beam has been taken into account. We give the optimized analytical solution of nonlinear transmission in a three-photon absorption (3PA ) process when the incident beam has a Gaussian transverse spatial profile.展开更多
In this study, a novel phenoxyethylamine derivative 1-(bis(4-methoxy phenyl)-methyl)-4-(2-(2-methylphenoxy)ethyl)piperazine(C28 H35 N2O3, Mr = 454.58) has been synthesized and its structure was characterized by 1 H NM...In this study, a novel phenoxyethylamine derivative 1-(bis(4-methoxy phenyl)-methyl)-4-(2-(2-methylphenoxy)ethyl)piperazine(C28 H35 N2O3, Mr = 454.58) has been synthesized and its structure was characterized by 1 H NMR, 13 C NMR, HRMS and single-crystal X-ray diffraction. The compound crystallizes in triclinic system, space group P1 with a = 6.1980(12),b = 12.212(2), c = 19.527(4)A,α= 93.08(3)°,β= 98.62(3)°,γ= 90.72(3)°, V = 1458.9(5)?3, Z =2, Dc = 1.035 g/cm^3, F(000)= 489,μ= 0.067 mm-1, Mo Kα radiation(λ= 0.71073 ?), the final R= 0.0693 and wR = 0.1759 for 3030 observed reflections with I > 2σ(I). The bioassay results indicated that the title compound 5 displayed effective activities against glutamine-induced neurotoxicity in PC12 cells.展开更多
One novel phenoxyacetamide derivative(C22H28N2O3, Mr = 368.47) has been synthesized and determined by means of NMR spectroscopy, high resolution mass spectra and single-crystal X-ray diffraction. The single crystal ...One novel phenoxyacetamide derivative(C22H28N2O3, Mr = 368.47) has been synthesized and determined by means of NMR spectroscopy, high resolution mass spectra and single-crystal X-ray diffraction. The single crystal belongs to the monoclinic system, space group Cc with a = 14.910(3), b = 14.592(3), c = 38.683(8) A^°, β = 100.37(3)°, V = 8279(3) ?3, Z = 16, Dc = 1.183 g/cm^3, F(000) = 3168, μ = 0.079 mm^-1, Mo Kα radiation(λ = 0.71073A^°), the final R = 0.0508 and wR = 0.0666 for 4120 observed reflections with I 〉 2σ(I). There are four independent molecules in an asymmetric unit cell. The four symmetry-independent molecules have a variety of different conformations indicating considerable conformational freedom. The bioassay results indicated that the title compound displayed effective activities against glutamine-induced neurotoxicity in PC12 cells and significantly prolonged the survival time of mice subjected to acute cerebral ischemia.展开更多
A new cinnamide derivative,(E)-1-(4-(bis(4-methoxyphenyl)methyl)piperazin-1-yl)-3-(4-acetoxy-3-methoxyphenyl)prop-2-en-1-one(C31H34N2O6,Mr = 530.60),has been synthesized by the condensation of 1-(bis(4-m...A new cinnamide derivative,(E)-1-(4-(bis(4-methoxyphenyl)methyl)piperazin-1-yl)-3-(4-acetoxy-3-methoxyphenyl)prop-2-en-1-one(C31H34N2O6,Mr = 530.60),has been synthesized by the condensation of 1-(bis(4-methoxyphenyl)methyl)piperazine and(E)-3-(4-acetoxy-3-methoxyphenyl)acrylic acid.The compound was characterized by 1H NMR,13 C NMR,H RMS and single-crystal X-ray diffraction.The crystal belongs to the orthorhombic system,space group P212121 with a = 24.946(5),b = 7.6380(15),c = 14.555(3) A,V = 2773.3(10) A^3,Z = 4,Dc = 1.271 g/cm^3,F(000) = 1128,μ = 0.088 mm-1,Mo Kα radiation(λ = 0.71073 A),the final R = 0.0641 and w R = 0.1170.A total of 3009 unique reflections were collected,of which 1760 with I 〉 2σ(I) were observed.Intramolecular C(17)–H(17B)···O(3) and C(22)–H(22A)···O(3) interactions as well as intermolecular C(27)–H(27A)···O(3) hydrogen bonds help to stabilize the crystal structure.The title compound was evaluated for the anti-ischemic activity in vitro and in vivo.The bioassay results indicated that the title compound displayed efficient activities against glutamine-induced neurotoxicity in PC12 cells and significantly prolonged the survival time of mice subjected to acute cerebral ischemia.展开更多
Azilsartan (2-ethoxy-1-([2’-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl)-1H-benzimidazole-7-carboxylic acid) is a new angiotensin II receptor antagonist used in the treatment of hypertension. This pa...Azilsartan (2-ethoxy-1-([2’-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl)-1H-benzimidazole-7-carboxylic acid) is a new angiotensin II receptor antagonist used in the treatment of hypertension. This paper describes the preparation of type I crystal and its single crystal diffraction data, the comparison of the powder diffraction data for both type I and II crystals as well as their stability and solubility in methanol.展开更多
基金the financial support from the National Natural Science Foundation of China(22278070,21978047,21776046)。
文摘The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceutical formulations.In this work,a developed machine-learning model efficiently predicts the solubility of APIs in polymers by learning the phase equilibrium principle and using a few molecular descriptors.Under the few-shot learning framework,thermodynamic theory(perturbed-chain statistical associating fluid theory)was used for data augmentation,and computational chemistry was applied for molecular descriptors'screening.The results showed that the developed machine-learning model can predict the API-polymer phase diagram accurately,broaden the solubility data of APIs in polymers,and reproduce the relationship between API solubility and the interaction mechanisms between API and polymer successfully,which provided efficient guidance for the development of pharmaceutical formulations.
基金supported by the National Natural Science Foundation of China(Grant Nos.21972068,21875112,and 22075290)the Nanjing IPE Institute of Green Manufacturing Industrythe Beijing Natural Science Foundation(Grant No.Z200012).
文摘The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future.
基金gratefully acknowledge the financial support for this research from the National Natural Science Foundation of China(Grant No.:21978047,21776046)the Six Talent Climax Foundation of Jiangsu(Grant No.:XCL-079).
文摘A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous structure.The adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic performance.Moreover,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical calculation.Considering the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.
基金supported by NSFC (nos 61471168, 61571187,61301043,and 61527806)China Postdoctoral Science Foundation (2016T90403)the Economical Forest Cultivation and Utilization of 2011 Collaborative Innovation Center in Hunan Province [(2013)448]
文摘Tissue engineering has become a promising strategy for repairing damaged cartilage and bone tissue. Among the scaffolds for tissue-engineering applications, injectable hydrogels have demonstrated great potential for use as three-dimensional cell culture scaffolds in cartilage and bone tissue engineering, owing to their high water content, similarity to the natural extracellular matrix(ECM), porous framework for cell transplantation and proliferation, minimal invasive properties, and ability to match irregular defects. In this review, we describe the selection of appropriate biomaterials and fabrication methods to prepare novel injectable hydrogels for cartilage and bone tissue engineering. In addition, the biology of cartilage and the bony ECM is also summarized. Finally, future perspectives for injectable hydrogels in cartilage and bone tissue engineering are discussed.
基金Supported by the National Natural Science Foundation of China (20476046) and the "Qinglan" Project of Jiangsu Province for Young Researchers.
文摘In order to solve the serious leaching problem of supported heteropoly acid catalysts in polar reaction media,12-molybdophosphoric acid encapsulated in the supercage of Cs+-exchanged Y zeolite was prepared by the "ship in the bottle" synthesis.The influence of ion-exchange conditions and the synthesis parameters on the encapsulation of PMo12 were investigated.The obtained solid sample was characterized by X-ray diffraction(XRD),31P magic angle spin nuclear magnetic resonance(MAS NMR) and Fourier Transform Infrared Spectroscopy(FT-IR),and its catalytic activity in the esterification of acetic acid and n-butanol was tested.The ion-exchange time,concentration of aqueous Cs+ solution,pH value,and amount of Mo added in the synthesis mixture were revealed to influence the encapsulation very remarkably.Under the optimal conditions,12-molybdophosphoric acid could be successfully encapsulated in the supercage of CsY zeolite,and the samples showed considerable catalytic activity and excellent reusability in the esterification reaction.
基金supported by the Scientific and Technological Development Plan of Jiangsu Province (BE2007014)the Natural Science Foundation of Jiangsu Province (BK2009293)National Basic Research Program of China (2007CB936300)
文摘Ce0.8Sm0.2O1.9(SDC) nanopowders were synthesized by an acrylamide polymerization process.The XRD results showed that SDC powders prepared at 700 °C possessed a cubic fluorite structure.Transmission electron microscopy(TEM) indicated that the particle sizes of powders were in the range of 10-15 nm.A 98.3% of theoretical density was obtained when the SDC pellets were sintered at 1350 °C for 5 h,indicating that the powders had good sinterability.The conductivity of the sintered SDC ceramics was 0.019 S/cm at 6...
基金Supported by the National Natural Science Foundation of China(No.81371451)the Natural Science Foundation of Jiangsu Province(No.BK20131390)
文摘A new phenoxyacetamide derivative, methyl 2-((4-(2-(2-methylphenoxy)acetyl)pi- perazin-1-yl)methyl)benzoate (C22H26N2O4, M, = 382.45), has been synthesized and characterized by 1H NMR, 13C NMR, H RMS and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P21c with a = 11.145(2), b = 13.667(3), c = 13.998(3) A, β= 112.01(3)°, V= 1976.8(7)A3, Z = 4, Dc = 1.285 g/cm3, F(000) = 816, g = 0.089 mml, MoKa radiation (λ= 0.71073 A), the final R = 0.0602 and wR = 0.1533 for 2343 observed reflections with I 〉 20(I). Intramolecular C-H……O interactions as well as intermolecular C-H……O hydrogen bonds help to stabilize the crystal structure. The preliminary bioassay results show that the title compound exhibits potent neuroprotective activity.
基金supported by the prospective joint research project of Jiangsu province(BY20122193)the Fundamental Research Funds for the Central Universities(CXZZ12_0119)
文摘Dexmedetomidine and its novel salt have been synthesized and characterized by single-crystal XRD and TGA/DSG. Components of the crystalline phase have also been investigated in terms of their corresponding Hirshfeld surface. In the crystal lattice, a three-dimensional hydrogen-bonded network is observed. In this work, the salt strategy has been applied successfully to dexmedetomidine. One important parameter, i.e. stability, has also been significantly improved, which proves to be an important factor for solid dosage formulation. Furthermore, DSC/TGA analysis indicates that the salt maintains its crystallinity up to 300℃, suggesting a higher stability of the salt compared to pure dexmedetomidine.
基金supported by the National Natural Science Foundation of China(No.20801012)New Energy Technology Co.Ltd.of Ai Naji of Jiangsu Province(No.8507040091)
文摘A novel Cd(Ⅱ) coordination polymer, [CdCI(Hpc)H2O]n (1, H2pc = 1H-pyrazole-3- carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-Vis spectrum, elemental analysis, single-crystal X-ray diffraction, as well as thermal analysis. Compound 1 crystallizes in monoclinic, P21/n space group with α = 7.0304(3), b = 10.3047(3), c = 10.6446(4) A, β= 107.174(4)°, F = 736.78(5) A^3, Z = 4, C4HsCdClN2O3, Mr = 276.95, Dc = 2.497 g/cm%3, F(000) = 528.0,μ= 3.281 mm^-1, R = 0.0169 and wR = 0.0387. The central metals adopt distorted octahedral geometry. Carboxyl groups of the ligand connect Cd(Ⅱ) into a one-dimensional chain, which further constructs a two-dimensional network by halogen bridging. Such two-dimensional structures are finally connected into a three-dimensional supramolecular architecture due to the hydrogen bonds and intermolecular π…π interactions. In addition, complex 1 has high thermal stability.
基金financially supported by the FDCT Project 0029/2018/A1the University of Macao Research Grants(MYRG2019-00041-ICMS)performed in part at the High-Performance Computing Cluster(HPCC)which is supported by Information and Communication Technology Office(ICTO)of the University of Macao。
文摘Current formulation development strongly relies on trial-and-error experiments in the laboratory by pharmaceutical scientists,which is time-consuming,high cost and waste materials.This research aims to integrate various computational tools,including machine learning,molecular dynamic simulation and physiologically based absorption modeling(PBAM),to enhance andrographolide(AG)/cyclodextrins(CDs)formulation design.The light GBM prediction model we built before was utilized to predict AG/CDs inclusion's binding free energy.AG/γ-CD inclusion complexes showed the strongest binding affinity,which was experimentally validated by the phase solubility study.The molecular dynamic simulation was used to investigate the inclusion mechanism between AG andγ-CD,which was experimentally characterized by DSC,FTIR and NMR techniques.PBAM was applied to simulate the in vivo behavior of the formulations,which were validated by cell and animal experiments.Cell experiments revealed that the presence of D-α-Tocopherol polyethylene glycol succinate(TPGS)significantly increased the intracellular uptake of AG in MDCKMDR1 cells and the absorptive transport of AG in MDCK-MDR1 monolayers.The relative bioavailability of the AG-CD-TPGS ternary system in rats was increased to 2.6-fold and 1.59-fold compared with crude AG and commercial dropping pills,respectively.In conclusion,this is the first time to integrate various computational tools to develop a new AG-CD-TPGS ternary formulation with significant improvement of aqueous solubility,dissolution rate and bioavailability.The integrated computational tool is a novel and robust methodology to facilitate pharmaceutical formulation design.
基金Supported by the National Natural Science Foundation of China(No.81371451)the Natural Science Foundation of Jiangsu Province(No.BK20131390)
文摘The crystal structure of the new cinnamide derivative(E)-1-(4-(4-chlorobenzyl)piperazin-1-yl)-3-(benzo[d][1,3]dioxol-5-yl)prop-2-en-1-one(C(21)H(21)ClN2O3, Mr = 384.85) was determined by single-crystal X-ray diffraction method. Compound 5 crystallizes in the monoclinic system, space group P21/c with a = 11.762(2), b = 15.279(3), c = 11.865(2) , β = 116.57(3)°, V = 1907.1(7) 3, Z = 4, Dc = 1.340 g/cm3, F(000) = 808, μ = 0.224 mm-1, Mo Kα radiation(λ = 0.71073 ), the final R = 0.0565 and w R = 0.1479 for 2318 observed reflections with I 〉 2σ(I). Intramolecular C(9)–H(9A)···O(1) interactions as well as intermolecular C(16)–H(16A)···O(1) hydrogen bonds help to stabilize the crystal structure. The bioassay results indicated that the title compound displayed promising neuroprotection in vitro and in vivo, and suppressed apoptosis of glutamate-induced PC12 cells.
基金supported by the prospective joint research project of Jiangsu province(BY20122193)the Fundamental Research Funds for the Central Universities(CXZZ12_0119)
文摘Since 2-aminonicotinic acid is a zwitterionic molecule,the salt or co-crystal strategy was used for the precipitation under identical conditions and obtained two novel salts: salt 1 with 2:1:2 stoichiometry of 2-aminonicotinic acid:perchloric acid:H2O and salt 2 with 2:1:3 stoichiometry of 2-aminonicotinic acid:sulfuric acid:H2O. Their crystal structures were characterized by single-crystal X-ray diffraction,differential scanning calorimetry(DSC) and thermogravimetric analyses(TGA). The structure determination shows that two salts are both primarily stabilized by the strong N–H…O hydrogen bonding interaction between 2-aminonicotinic acid and its corresponding acids. Constituents of the salt-crystalline phase were also investigated in terms of Hirshfeld surfaces. In the crystal lattice,a three-dimensional hydrogen-bonded network is observed,including the formation of a two-dimensional molecular scaffolding motif. Hirshfeld surfaces and fingerprint plots of two salts show that the structures are stabilized by H…H,O–H…O and C–O…π intermolecular interactions.
基金Project(2008AA03323) supported by the High-Tech Research and Development of ChinaProject(21374016) supported by the National Natural Science Foundation of ChinaProject(BY201153) supported by Production,Forward-Looking Joint Research Project of Jiangsu Province,China
文摘The matrix polymer PTBCHNB bearing o-nitrobenzyl group was successfully synthesized by copolymerization of tertiary-butyl methacrylate(TBMA), cyclohexyl methacrylate(CHMA) and o-nitrobenzyl methacrylate(NBMA) via reversible addition fragmentation chain transfer(RAFT) polymerization method. PTBCHNB was characterized by FTIR, 1HNMR, GPC and DSC. After UV irradiation, the o-nitrobenzyl groups of PTBCHNB were photocleaved and the resulting carboxyl groups were highly alkali soluble, and PTBCHNB was converted to PCHIBMA bearing carboxyl groups. So, the matrix polymer could be etched by mild alkali solution with no requirements of photoacid generators and other diverse additives. The photocleavable behaviors of PTBCHNB were determined by FTIR, 1H NMR and TGA analysis. The resist formulated with PTBCHNB and cast in THF solution showed square pattern of 10 μm×10 μm using a mercury-xenon lamp in a contact printing mode and tetramethyl-ammonium hydroxide aqueous solution as a developer.
基金Supported by the Natural Science Foundation of Southeast University under Grant No XJ0706271. We thank Professor Long Ba, Guohua Hu and Yuqiao Wang for help in the process of device preparation and measurements.
文摘ZnO is introduced as an alternative to TiO2 in dye sensitized solar cells (DSSCs) due to its band gap similar to TiO2, higher electron mobility, and flexible procedures of preparations. Several samples of ZnO films are prepared with the hydrothermal synthesis method and the sol-gel technique, respectively. These ZnO films were assembled as photoanodes in DSSCs using N3 dye as the sensitizer. The ZnO-based cells prepared by the hydrothermal synthesis show typical current source characteristics, whose fill factor (FF) is 0.44 and photo-to-electric power conversion efficiency is 0.34%. On the other hand, all the samples prepared with the sol-gel technique show accompanied source characteristics with relatively higher power conversion efficiencies (1%) but a lower FF (0.26). X-ray diffraction (XRD) and atomic force microscopy (AFM) measurements indicate that the sol-gel samples have small particles sizes. Therefore, sol-gel samples could adsorb more dye molecules to generate high conversion efficiencies. At the same time, more grain boundaries make it more possible for injected electrons to recombine with the oxidized electrolyte. Hydrothermal samples have bigger grains, so they show poor conversion efficiency and relatively high FF.
基金Supported by the National Natural Science Foundation of China under Grant No 60708024 and 60678042, and the Natural Science Foundation of Jiangsu Province (BK2006553).
文摘A newly synthesized 1,3,4-oxadiazole derivatives have been studied using a femtosecond Ti:sapphire laser system. The series molecules present strong three-photon absorption and frequency upeonversion fluorescence at wavelengths from 1205 nm to 1575 nm. Furthermore, there is no proportional relationship between three-photon absorption cross sections and the chemical structure transformation from monomer, dimer to trimer. Effective charge-transfer distance by π-conjugation bonds may be the contributing factor. In the experimental design, the far-field intensity distribution of femtosecond laser beam has been taken into account. We give the optimized analytical solution of nonlinear transmission in a three-photon absorption (3PA ) process when the incident beam has a Gaussian transverse spatial profile.
基金Supported by the National Natural Science Foundation of China(No.81371451)the Natural Science Foundation of Jiangsu Province(No.BK20131390,BK20151444)
文摘In this study, a novel phenoxyethylamine derivative 1-(bis(4-methoxy phenyl)-methyl)-4-(2-(2-methylphenoxy)ethyl)piperazine(C28 H35 N2O3, Mr = 454.58) has been synthesized and its structure was characterized by 1 H NMR, 13 C NMR, HRMS and single-crystal X-ray diffraction. The compound crystallizes in triclinic system, space group P1 with a = 6.1980(12),b = 12.212(2), c = 19.527(4)A,α= 93.08(3)°,β= 98.62(3)°,γ= 90.72(3)°, V = 1458.9(5)?3, Z =2, Dc = 1.035 g/cm^3, F(000)= 489,μ= 0.067 mm-1, Mo Kα radiation(λ= 0.71073 ?), the final R= 0.0693 and wR = 0.1759 for 3030 observed reflections with I > 2σ(I). The bioassay results indicated that the title compound 5 displayed effective activities against glutamine-induced neurotoxicity in PC12 cells.
基金Supported by the National Natural Science Foundation of China(No.81371451)the Natural Science Foundation of Jiangsu Province(No.BK20131390)
文摘One novel phenoxyacetamide derivative(C22H28N2O3, Mr = 368.47) has been synthesized and determined by means of NMR spectroscopy, high resolution mass spectra and single-crystal X-ray diffraction. The single crystal belongs to the monoclinic system, space group Cc with a = 14.910(3), b = 14.592(3), c = 38.683(8) A^°, β = 100.37(3)°, V = 8279(3) ?3, Z = 16, Dc = 1.183 g/cm^3, F(000) = 3168, μ = 0.079 mm^-1, Mo Kα radiation(λ = 0.71073A^°), the final R = 0.0508 and wR = 0.0666 for 4120 observed reflections with I 〉 2σ(I). There are four independent molecules in an asymmetric unit cell. The four symmetry-independent molecules have a variety of different conformations indicating considerable conformational freedom. The bioassay results indicated that the title compound displayed effective activities against glutamine-induced neurotoxicity in PC12 cells and significantly prolonged the survival time of mice subjected to acute cerebral ischemia.
基金Acknowledgements: The authors are grateful to the National Nature Science Foundation of China (No. 50873026), Science and Technology Support Program of Jiangsu Province of China (No. BE2008129), "Six Talents Pinnacle Program" of Jiangsu Province of China (No. 06-A-033) and Excellent Doctoral Thesis Foundation of Southeast University for financial supports.
基金Supported by the National Natural Science Foundation of China(No.81371451)the Natural Science Foundation of Jiangsu Province(No.BK20131390)
文摘A new cinnamide derivative,(E)-1-(4-(bis(4-methoxyphenyl)methyl)piperazin-1-yl)-3-(4-acetoxy-3-methoxyphenyl)prop-2-en-1-one(C31H34N2O6,Mr = 530.60),has been synthesized by the condensation of 1-(bis(4-methoxyphenyl)methyl)piperazine and(E)-3-(4-acetoxy-3-methoxyphenyl)acrylic acid.The compound was characterized by 1H NMR,13 C NMR,H RMS and single-crystal X-ray diffraction.The crystal belongs to the orthorhombic system,space group P212121 with a = 24.946(5),b = 7.6380(15),c = 14.555(3) A,V = 2773.3(10) A^3,Z = 4,Dc = 1.271 g/cm^3,F(000) = 1128,μ = 0.088 mm-1,Mo Kα radiation(λ = 0.71073 A),the final R = 0.0641 and w R = 0.1170.A total of 3009 unique reflections were collected,of which 1760 with I 〉 2σ(I) were observed.Intramolecular C(17)–H(17B)···O(3) and C(22)–H(22A)···O(3) interactions as well as intermolecular C(27)–H(27A)···O(3) hydrogen bonds help to stabilize the crystal structure.The title compound was evaluated for the anti-ischemic activity in vitro and in vivo.The bioassay results indicated that the title compound displayed efficient activities against glutamine-induced neurotoxicity in PC12 cells and significantly prolonged the survival time of mice subjected to acute cerebral ischemia.
文摘Azilsartan (2-ethoxy-1-([2’-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl)-1H-benzimidazole-7-carboxylic acid) is a new angiotensin II receptor antagonist used in the treatment of hypertension. This paper describes the preparation of type I crystal and its single crystal diffraction data, the comparison of the powder diffraction data for both type I and II crystals as well as their stability and solubility in methanol.