In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented...In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.展开更多
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
Calcium lignosulphonate was used to synthesize a spherical lignosulphonate resin in a cheap and non-toxic disperse medium by reversed phase suspension polymerization. The process conditions were optimized by orthog...Calcium lignosulphonate was used to synthesize a spherical lignosulphonate resin in a cheap and non-toxic disperse medium by reversed phase suspension polymerization. The process conditions were optimized by orthogonal experiments. Under .the optxmal conditxons （T=95 ℃, CHCl= 3 mol·L^-1, mHCHO： mCLS=7%, WCLS=50%）, globulation took about 20 min and the product was featured with excellent spherical shape, narrow particle size range, 61.20% of water retention capacity, 0.83 mmol·ml^- 1 of total volume exchange capacity and 3.46 mmol·g^- 1 of total exchange capacity. The results of Scanning Electron Micrograph and Scanning Probe Micrograph indicate that spherical lignosulphonate resin has a rugged surface with porous microstructure in the gel skeleton. The average pore size of dry samples was determined to be 10.46 nm. by the BET method.展开更多
This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional l...This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional linear variation the rays of quasi-stationary planetary wave may propagate along oblique lines and if the meridional variability of heat source has second order term the rays show distinct deformation as a great circular route. Additionally, the inhomogeneous distribution may cause lower frequency oscillations in mid- and low-latitudes. The combination of zonal and meridional wave numbers and distributive character of heat source may form an inverse mechanism of variational trend of generized wave energy, reflecting in some degree the physical process of transition between meridional and zonal flow patterns.展开更多
[ Objective] This study aimed to characterize the structure of soybean glycinin affected by limited enzymatic hydrolysis. [ Method ] The glycinin was limitedly hydrolyzed by alkaline protease; then the SDS-polyacrylam...[ Objective] This study aimed to characterize the structure of soybean glycinin affected by limited enzymatic hydrolysis. [ Method ] The glycinin was limitedly hydrolyzed by alkaline protease; then the SDS-polyacrylamide gel electrophoresis （SDS-PAGE）, scanning electron microscopy （SEM）, Fourier transform infrared spectroscopy （fTIR） and other means were performed to characterize the glyeinin structure changing during the hydrolysis process. [ Result] SDS-PAGE analysis showed that the subunit contem of glycinin significantly decreased after hydrolysis, and acidic subunits were more susceptible to hydrolysis than alkaline subunits. The scanning electron microscopy revealed that the structure of glycinin powder changed greatly after hydrolysis. The I^TIR results showed that the propor- tions of all conformations of glycinin changed greatly during hydrolysis process. In addition, the protein hydrophobicity and sulfhydryl content were also significantly influenced by hydrolysis. [ Conclusion] The enzymatic hydrolysis greatly changed the conformations of glyeinin, and the change was dependent on the degree of hy- drolysis.展开更多
Dictyophora rubrovalvata is a valuable fungus homologous to food and medicine,and its polysaccharide have been gaining increasing attention because of its plentiful activity.However,the structure and activity of its h...Dictyophora rubrovalvata is a valuable fungus homologous to food and medicine,and its polysaccharide have been gaining increasing attention because of its plentiful activity.However,the structure and activity of its homogeneous polysaccharide have not been studied enough.In this study,two polysaccharides DRP-I and DRP-II were purified from D.rubrovalvata.Their structures were characterized by chemical composition,monosaccharide composition analysis,methylation analysis and nuclear magnetic resonance spectroscopy.The results showed that DRP-I and DRP-II were neutral heteropolysaccharides with molecular weights of 5.79×103 and 1.25×104 Da,respectively,which were composed of mannose,galactose,glucose,xylose and fucose.The main chains were→6)-α-D-Galp-(1→6)-α-D-Galp-(2,1→6)-α-D-Manp-(2,1→6)-α-D-Galp-(1,and branch chains wereβ-D-Xylp-(1→3)-α-L-Fucp-(1→4)-α-D-Manp-(1→andα-D-Galp-(1→3)-α-D-Galp-(1→.The in vitro immunoactivity assays on dendritic cells showed that DRP-I and DRP-II could up-regulate the expression of IL-10 and IL-6 and inhibit the expression of TNF-αin a concentration-dependent manner.This research indicated that DRP-I and DRP-II possessed immunoactivity by balancing the excessive inflammation,and molecular weight is an important factor affecting immunoactivity.展开更多
The hot wall reactor was used to deposit isotropic pyrocarbon.The density of the product was measured by Archimedes method.The fracture morphology and texture of the product were investigated by scanning electron micr...The hot wall reactor was used to deposit isotropic pyrocarbon.The density of the product was measured by Archimedes method.The fracture morphology and texture of the product were investigated by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Raman spectroscopy was also applied to characterizing the structure of the product.The results show that the density of the product is about 1.31 g/cm^3.The pyrocarbon consists of granular particles with the size of about 1.5μm under SEM images.Under TEM images,the pyrocarbon is composed of irregular grains and onion-like particles are also detected.The orientation angle(180 deg.)of pyrocarbon reveals its isotropic character.The ID/IG ratio in Raman spectrum is about 1.2,indicating the isotropic feature of the product qualitatively.展开更多
One organic-decorated quanternaery [TM（1,2-dap）3]Hg Sb2Se5（1,2-dap = 1,2-dianinopropane, TM = Co（1）, Fe（2）） compound has been solvothermally synthesized. The compounds crystallize in triclinic space group P 1,...One organic-decorated quanternaery [TM（1,2-dap）3]Hg Sb2Se5（1,2-dap = 1,2-dianinopropane, TM = Co（1）, Fe（2）） compound has been solvothermally synthesized. The compounds crystallize in triclinic space group P 1, with a = 11.248（6）, b = 11.542（7）, c = 12.180（12） A, V =1268.7（16） A^3, Z = 2, F（000） = 1010 for 1 and a = 11.311（5）, b = 11.558（5）, c = 12.180（9） A, V =1276.5（12） A^3, Z = 2, F（000） = 1008 for 2. The crystal structure consists of one-dimensional anionics chains composed of Hg Se4 tetrahedra and SbSe3 trigonal pyramids sharing corners and[TM（dap）3]^2＋ cations. The [HgSb2Se＋5^2-]∞ anionic chains run along the [001] direction, and are surrounded by the [TM（dap）3]^2＋ cations. Meanwhile, 8-ring [Hg2Sb2Se4] and 6-ring [HgSb2Se2] are alternately found. The compounds were structurally characterized by elemental analysis,thermogravimetric analysis, infrared spectroscopy and UV-Vis diffuse reflectance spectroscopy.展开更多
Structural and functional explorations on bio-soft matter such as micelles,vesicles,nanoparticles,aggregates or polymers derived from traditional Chinese medicine(TCM)has emerged as a new topic in the field of TCM.The...Structural and functional explorations on bio-soft matter such as micelles,vesicles,nanoparticles,aggregates or polymers derived from traditional Chinese medicine(TCM)has emerged as a new topic in the field of TCM.The discovery of such cross-scaled bio-soft matter may provide a unique perspective for unraveling the new effective material basis of TCM as well as developing innovative medicine and biomaterials.Despite the rapid rise of TCM-derived bio-soft matter,their hierarchical structure and assembly mechanism must be unambiguously probed for a further in-depth understanding of their pharmacological activity.In this review,the current emerged TCM-derived bio-soft matter assembled from either small molecules or macromolecules is introduced,and particularly the unambiguous elucidation of their hierarchical structure and assembly mechanism with combined electron microscopic and spectroscopic techniques is depicted.The pros and cons of each technique are also discussed.The future challenges and perspective of TCM-derived bio-soft matter are outlined,particularly the requirement for their precise in situ structural determination is highlighted.展开更多
Molten salt synthesis （MSS） method has advantages of the simplicity in the process equipment, versatile and large-scale synthesis, and friendly environment, which provides an excellent approach to synthesize high pu...Molten salt synthesis （MSS） method has advantages of the simplicity in the process equipment, versatile and large-scale synthesis, and friendly environment, which provides an excellent approach to synthesize high pure oxide powders with controllable compositions and morphologies. Among these oxides, perovskite oxides with a composition of ABO3 exhibit a broad spectrum of physical properties and functions （e.g. ferroelectric, piezoelectric, magnetic, photovoltaic and photocatalytic properties）. The downscaling of the spatial geometry of perovskite oxides into nanometers result in novel properties that are different from the bulk and film counterparts. Recent interest in nanoscience and nanotechnology has led to great efforts focusing on the synthesis of low-dimensional perovskite oxide nanostructures （PONs） to better understand their novel physical properties at nanoscale. Therefore, the low-dimensional PONs such as perovskite nanoparticles, nanowires, nanorods, nanotubes, nanofibers, nanobelts, and two dimensional oxide nanostructures, play an important role in developing the next generation of oxide electronics. In the past few years, much effort has been made on the synthesis of PONs by MSS method and their structural characterizations. The functional applications of PONs are also explored in the fields of storage memory, energy harvesting, and solar energy conversion. This review summarizes the recent progress in the synthesis of low-dimensional PONs by MSS method and its modified ways. Their structural char- acterization and physical properties are also scrutinized. The potential applications of low-dimensional PONs in different fields such as data memory and storage, energy harvesting, solar energy conversion, are highlighted. Perspectives concerning the future research trends and challenges of low-dimensional PONs are also outlined. ~ 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.展开更多
Powder charges of micron-size Ni and Al2O3were utilized to deposit nano-structured Ni-Al2O3composite coatings on analuminum plate fixed at the top end of a milling vial using a planetary ball mill.Composite coatings w...Powder charges of micron-size Ni and Al2O3were utilized to deposit nano-structured Ni-Al2O3composite coatings on analuminum plate fixed at the top end of a milling vial using a planetary ball mill.Composite coatings were fabricated using powdermixtures with a wide range of Ni/Al2O3mass ratio varying from1:1to plain Ni.XRD,SEM and TEM techniques were employed tostudy the structural characteristics of the coatings.It was found that the composition of the starting mixture strongly affects the Al2O3content and the microstructure of the final coating.Mixtures containing higher contents of Al2O3yield higher volume fractions of theAl2O3particles in the coating.Though Ni-Al2O3composite coatings with about50%of Al2O3particles were successfully deposited,well-compacted and free of cracks and/or voids coatings included less than20%(volume fraction)of Al2O3particles which weredeposited from powder mixtures with Ni/Al2O3mass ratios of4:1or higher.Moreover,mechanical and metallurgical bondings arethe main mechanisms of the adhesion of the coating to the Al substrate.Finally,functionally graded composite coatings withnoticeable compaction and integrity were produced by deposition of two separate layers under identical coating conditions.展开更多
6 Atomic fragment types of organic compound have been defined, and the multilevel atom-pair frequency matrix has been constructed according to the occurrence number in pairs of atomic fragments with different bond len...6 Atomic fragment types of organic compound have been defined, and the multilevel atom-pair frequency matrix has been constructed according to the occurrence number in pairs of atomic fragments with different bond lengths in the molecule. On the basis of them, a novel molecular coding technique： characteristic atom-pair holographic code （CAHC）, is obtained. To some extent, this method exhibits a large number of benefits at the same time. For example, it can calculate 2D molecular topological descriptor easily, operate without difficulty and possess definite physicochemical meaning of 3D molecular structural characterization methods, and may fetch the complicated information of molecule, etc. Therefore, it is appropriate for the study on quantitative structure-property/activity relationship （QSPR/QSAR） of medicines and biological molecules. We attempt in this paper to utilize the method of CAHC to the quantitative prediction of reversed-phase liquid chromatogram （RPLC） retention data of 33 purine derivatives and 24 steroids. The fitting multiple correlation coefficient R2, cross-validated multiple correlation coefficient Q2 and predicted ability Q^2 pred over test set＇s samples of obtained partial least-square （PLS） regression model are respectively 0.990, 0.893 and 0.977, 0.897, 0.941.展开更多
For the frequency range of I kHz-lOMHz, the interface state density of Ni contacts on p-GaN is studied using capacitance-voltage （C-V） and conductance-frequency-voltage （G-f-V） measurements at room temperature. To...For the frequency range of I kHz-lOMHz, the interface state density of Ni contacts on p-GaN is studied using capacitance-voltage （C-V） and conductance-frequency-voltage （G-f-V） measurements at room temperature. To obtain the real capacitance and interface state density of the Ni/p-GaN structures, the effects of the series resistance （Rs） on high-frequency （SMHz） capacitance values measured at a reverse and a forward bias are investigated. The mean interface state densities obtained from the CHF-CLF capacitance and the conductance method are 2 ×1012 e V-1 cm-2 and 0.94 × 1012 eV-1 cm-2, respectively. Furthermore, the interface state density derived from the conductance method is higher than that reported from the Ni/n-GaN in the literature, which is ascribed to a poor crystal quality and to a large defect density of the Mg-doped p-GaN.展开更多
A new polymeric iodoplumbate complex [Zn（DMF）6][Pb2I6] 1 has been prepared and characterized by elemental analysis and single-crystal X-ray analysis. Its structure contains infinite iodoplumbate chains constructed b...A new polymeric iodoplumbate complex [Zn（DMF）6][Pb2I6] 1 has been prepared and characterized by elemental analysis and single-crystal X-ray analysis. Its structure contains infinite iodoplumbate chains constructed by the [PbI5] subunit. EHT crystal orbital calculation and the experimental results show that this material is an unconventional semiconductor and the electrical character is associated with its structural feature.展开更多
The mono-α-nitronyl nitroxide substituted diacetylene was synthesized and its structure was established by EA,FAB-MS,IR,ESR and x-ray diffraction analysis.Using the Extracting Sample Magnetometer,its magnetic propert...The mono-α-nitronyl nitroxide substituted diacetylene was synthesized and its structure was established by EA,FAB-MS,IR,ESR and x-ray diffraction analysis.Using the Extracting Sample Magnetometer,its magnetic properties was investigated,and the results indicate that this compound possesses antiferromagnetic properties.展开更多
A series of lanthanide complexes LnCl_3·L(Ln=La,Pr,Nd;L=15-C-5 or 18-C-6)have been synthesized and their molecular configuration,electronic structure and bond character have been studied by XPS and quantum chemic...A series of lanthanide complexes LnCl_3·L(Ln=La,Pr,Nd;L=15-C-5 or 18-C-6)have been synthesized and their molecular configuration,electronic structure and bond character have been studied by XPS and quantum chemical calculation.The calculated results are in good agreement with that obtained in the experiments.Three Cl atoms are on the same side of Ln in LnCl_3·15-C-5 and the crown ring on the other side.forming a complex molecule with coordination number 8.LnCl_3·15-C-5 is easily hygroscopic in air because of its unsaturated coordination,which differs sharply from the stable Ln(NO_3)_3·15-C-5 com- plex of coordination number 11.The HOMO and neighboring occupied MOs are composed of Cl 3p and O2p, and the LUMO and neighboring unoccupied MOs are composed of Ln orbitals.The level structure easily pro- duces Ln3d satellite in XPS caused by L→Ln charge transfer transition.Due to the coordination,the absolute values of the charge are decreased at Ln and O atoms,but increased at Cl atoms,which is in agreement with XPS results.展开更多
In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystal...In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2), c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is 0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism.展开更多
Synthesis of complexes（η;-CH;C;H;）M（CO）;NO（M=Mo,I;M=W,II）and clusters（η;-CH;C;H;）M（μ;-NH）(μ;-NO) （μ;-CO）Fe;（CO）;（M=Mo,III:M=W,IV）,based on the reaction of （η;-C5;）M（CO）;Cl with Na[Fe（CO）;NO...Synthesis of complexes（η;-CH;C;H;）M（CO）;NO（M=Mo,I;M=W,II）and clusters（η;-CH;C;H;）M（μ;-NH）(μ;-NO) （μ;-CO）Fe;（CO）;（M=Mo,III:M=W,IV）,based on the reaction of （η;-C5;）M（CO）;Cl with Na[Fe（CO）;NO] at room tem-perature,have been demonstrated,The crystal structures of II and IV arealso presented.展开更多
This data set collects,compares and contrasts the capacities and structures of a series of hard carbon materials,and then searches for correlations between structure and electrochemical performance.The capacity data o...This data set collects,compares and contrasts the capacities and structures of a series of hard carbon materials,and then searches for correlations between structure and electrochemical performance.The capacity data of the hard carbons were obtained by charge/discharge tests and the materials were characterized by XRD,gas adsorption,true density tests and SAXS.In particular,the fitting of SAXS gave a series of structural parameters which showed good characterization.The related test details are given with the structural data of the hard carbons and the electrochemical performance of the sodium-ion batteries.展开更多
Sea buckthorn(Hippophae rhamnoides L.)is a natural homologous substance of medicine and food.Polysaccharide,as one of its primary active components,has very superior biological activity and can be used as a dietary su...Sea buckthorn(Hippophae rhamnoides L.)is a natural homologous substance of medicine and food.Polysaccharide,as one of its primary active components,has very superior biological activity and can be used as a dietary supplement for functional foods,with good commercial prospects.Although initial progress has been made in the study of sea buckthorn polysaccharides,related studies have been fragmented and lacked systematic and generalization.This manuscript presents a critical analysis and systematic summary of the extraction and purification methods,structural characterization and physicochemical properties,biological activity and potential mechanisms,and structure-activity relationships of sea buckthorn polysaccharides.Accumulating evidence has indicated that sea buckthorn polysaccharides,which were widely prepared by water extraction and column chromatography purifications,exhibited exhibit superior biological activities in vitro and in vivo,including antioxidant,immunomodulatory,anti-inflammatory,hepatorenal protective,antibacterial,antiviral,and prebiotic activities.After analysis,it was concluded that there is a correlation between the relevant activities of sea buckthorn polysaccharides and that the structure of sea buckthorn polysaccharides has a great influence on their biological activity.We reviewed the challenges and limitations of sea buckthorn polysaccharides,summarized the critical aspects,and provided suggestions for potential breakthroughs in the research and application of sea buckthorn polysaccharide.展开更多
基金Supported by the National Key Research and Development Program of Traditional Chinese Medicine Modernization Project,China(No.2023YFC3504000)the Science and Technology Development Project of Jilin Province,China(No.20240404043ZP)the Science and Technology Innovation Cooperation Project of Changchun Science and Technology Bureau and Chinese Academy of Sciences,China(No.23SH14)。
文摘In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.
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the Ph.D. Programs Foundation of Ministry of Education of China (20020561001)
文摘Calcium lignosulphonate was used to synthesize a spherical lignosulphonate resin in a cheap and non-toxic disperse medium by reversed phase suspension polymerization. The process conditions were optimized by orthogonal experiments. Under .the optxmal conditxons （T=95 ℃, CHCl= 3 mol·L^-1, mHCHO： mCLS=7%, WCLS=50%）, globulation took about 20 min and the product was featured with excellent spherical shape, narrow particle size range, 61.20% of water retention capacity, 0.83 mmol·ml^- 1 of total volume exchange capacity and 3.46 mmol·g^- 1 of total exchange capacity. The results of Scanning Electron Micrograph and Scanning Probe Micrograph indicate that spherical lignosulphonate resin has a rugged surface with porous microstructure in the gel skeleton. The average pore size of dry samples was determined to be 10.46 nm. by the BET method.
文摘This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional linear variation the rays of quasi-stationary planetary wave may propagate along oblique lines and if the meridional variability of heat source has second order term the rays show distinct deformation as a great circular route. Additionally, the inhomogeneous distribution may cause lower frequency oscillations in mid- and low-latitudes. The combination of zonal and meridional wave numbers and distributive character of heat source may form an inverse mechanism of variational trend of generized wave energy, reflecting in some degree the physical process of transition between meridional and zonal flow patterns.
基金Supported by 863 Program(2006AA10Z330)New Century High-level Talent Project in Hubei Province[(2003)31]
文摘[ Objective] This study aimed to characterize the structure of soybean glycinin affected by limited enzymatic hydrolysis. [ Method ] The glycinin was limitedly hydrolyzed by alkaline protease; then the SDS-polyacrylamide gel electrophoresis （SDS-PAGE）, scanning electron microscopy （SEM）, Fourier transform infrared spectroscopy （fTIR） and other means were performed to characterize the glyeinin structure changing during the hydrolysis process. [ Result] SDS-PAGE analysis showed that the subunit contem of glycinin significantly decreased after hydrolysis, and acidic subunits were more susceptible to hydrolysis than alkaline subunits. The scanning electron microscopy revealed that the structure of glycinin powder changed greatly after hydrolysis. The I^TIR results showed that the propor- tions of all conformations of glycinin changed greatly during hydrolysis process. In addition, the protein hydrophobicity and sulfhydryl content were also significantly influenced by hydrolysis. [ Conclusion] The enzymatic hydrolysis greatly changed the conformations of glyeinin, and the change was dependent on the degree of hy- drolysis.
基金Key Project of Yunnan Provincial Nature Foundation(202401AS070075)。
文摘Dictyophora rubrovalvata is a valuable fungus homologous to food and medicine,and its polysaccharide have been gaining increasing attention because of its plentiful activity.However,the structure and activity of its homogeneous polysaccharide have not been studied enough.In this study,two polysaccharides DRP-I and DRP-II were purified from D.rubrovalvata.Their structures were characterized by chemical composition,monosaccharide composition analysis,methylation analysis and nuclear magnetic resonance spectroscopy.The results showed that DRP-I and DRP-II were neutral heteropolysaccharides with molecular weights of 5.79×103 and 1.25×104 Da,respectively,which were composed of mannose,galactose,glucose,xylose and fucose.The main chains were→6)-α-D-Galp-(1→6)-α-D-Galp-(2,1→6)-α-D-Manp-(2,1→6)-α-D-Galp-(1,and branch chains wereβ-D-Xylp-(1→3)-α-L-Fucp-(1→4)-α-D-Manp-(1→andα-D-Galp-(1→3)-α-D-Galp-(1→.The in vitro immunoactivity assays on dendritic cells showed that DRP-I and DRP-II could up-regulate the expression of IL-10 and IL-6 and inhibit the expression of TNF-αin a concentration-dependent manner.This research indicated that DRP-I and DRP-II possessed immunoactivity by balancing the excessive inflammation,and molecular weight is an important factor affecting immunoactivity.
基金supported by the National Natural Science Foundation of China under Grant Nos.50832004 and 50972120the Program of Introducing Talents of Discipline to University under Grant No.D08040
文摘The hot wall reactor was used to deposit isotropic pyrocarbon.The density of the product was measured by Archimedes method.The fracture morphology and texture of the product were investigated by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Raman spectroscopy was also applied to characterizing the structure of the product.The results show that the density of the product is about 1.31 g/cm^3.The pyrocarbon consists of granular particles with the size of about 1.5μm under SEM images.Under TEM images,the pyrocarbon is composed of irregular grains and onion-like particles are also detected.The orientation angle(180 deg.)of pyrocarbon reveals its isotropic character.The ID/IG ratio in Raman spectrum is about 1.2,indicating the isotropic feature of the product qualitatively.
基金supported by the National Natural Science Foundation of China(No.21461019)
文摘One organic-decorated quanternaery [TM（1,2-dap）3]Hg Sb2Se5（1,2-dap = 1,2-dianinopropane, TM = Co（1）, Fe（2）） compound has been solvothermally synthesized. The compounds crystallize in triclinic space group P 1, with a = 11.248（6）, b = 11.542（7）, c = 12.180（12） A, V =1268.7（16） A^3, Z = 2, F（000） = 1010 for 1 and a = 11.311（5）, b = 11.558（5）, c = 12.180（9） A, V =1276.5（12） A^3, Z = 2, F（000） = 1008 for 2. The crystal structure consists of one-dimensional anionics chains composed of Hg Se4 tetrahedra and SbSe3 trigonal pyramids sharing corners and[TM（dap）3]^2＋ cations. The [HgSb2Se＋5^2-]∞ anionic chains run along the [001] direction, and are surrounded by the [TM（dap）3]^2＋ cations. Meanwhile, 8-ring [Hg2Sb2Se4] and 6-ring [HgSb2Se2] are alternately found. The compounds were structurally characterized by elemental analysis,thermogravimetric analysis, infrared spectroscopy and UV-Vis diffuse reflectance spectroscopy.
基金supported by the National Natural Science Foundation of China(Grant No.:82374033,21901067)Ministry of Science and Technology of China(Grant No.:2023YFC3504100)Starting Grant from the Ministry of Human Resource and Social Security of China(Quan Li).
文摘Structural and functional explorations on bio-soft matter such as micelles,vesicles,nanoparticles,aggregates or polymers derived from traditional Chinese medicine(TCM)has emerged as a new topic in the field of TCM.The discovery of such cross-scaled bio-soft matter may provide a unique perspective for unraveling the new effective material basis of TCM as well as developing innovative medicine and biomaterials.Despite the rapid rise of TCM-derived bio-soft matter,their hierarchical structure and assembly mechanism must be unambiguously probed for a further in-depth understanding of their pharmacological activity.In this review,the current emerged TCM-derived bio-soft matter assembled from either small molecules or macromolecules is introduced,and particularly the unambiguous elucidation of their hierarchical structure and assembly mechanism with combined electron microscopic and spectroscopic techniques is depicted.The pros and cons of each technique are also discussed.The future challenges and perspective of TCM-derived bio-soft matter are outlined,particularly the requirement for their precise in situ structural determination is highlighted.
基金the financial support from the National Natural Science Foundation of China(Grant Nos.11674161,11174122 and 11134004)the Six Big Talent Peak Project from Jiangsu Province(Grant No.XCL-004)open project of National Laboratory of Solid State Microstructures,Nanjing University(Grant No.M28026)
文摘Molten salt synthesis （MSS） method has advantages of the simplicity in the process equipment, versatile and large-scale synthesis, and friendly environment, which provides an excellent approach to synthesize high pure oxide powders with controllable compositions and morphologies. Among these oxides, perovskite oxides with a composition of ABO3 exhibit a broad spectrum of physical properties and functions （e.g. ferroelectric, piezoelectric, magnetic, photovoltaic and photocatalytic properties）. The downscaling of the spatial geometry of perovskite oxides into nanometers result in novel properties that are different from the bulk and film counterparts. Recent interest in nanoscience and nanotechnology has led to great efforts focusing on the synthesis of low-dimensional perovskite oxide nanostructures （PONs） to better understand their novel physical properties at nanoscale. Therefore, the low-dimensional PONs such as perovskite nanoparticles, nanowires, nanorods, nanotubes, nanofibers, nanobelts, and two dimensional oxide nanostructures, play an important role in developing the next generation of oxide electronics. In the past few years, much effort has been made on the synthesis of PONs by MSS method and their structural characterizations. The functional applications of PONs are also explored in the fields of storage memory, energy harvesting, and solar energy conversion. This review summarizes the recent progress in the synthesis of low-dimensional PONs by MSS method and its modified ways. Their structural char- acterization and physical properties are also scrutinized. The potential applications of low-dimensional PONs in different fields such as data memory and storage, energy harvesting, solar energy conversion, are highlighted. Perspectives concerning the future research trends and challenges of low-dimensional PONs are also outlined. ~ 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.
文摘Powder charges of micron-size Ni and Al2O3were utilized to deposit nano-structured Ni-Al2O3composite coatings on analuminum plate fixed at the top end of a milling vial using a planetary ball mill.Composite coatings were fabricated using powdermixtures with a wide range of Ni/Al2O3mass ratio varying from1:1to plain Ni.XRD,SEM and TEM techniques were employed tostudy the structural characteristics of the coatings.It was found that the composition of the starting mixture strongly affects the Al2O3content and the microstructure of the final coating.Mixtures containing higher contents of Al2O3yield higher volume fractions of theAl2O3particles in the coating.Though Ni-Al2O3composite coatings with about50%of Al2O3particles were successfully deposited,well-compacted and free of cracks and/or voids coatings included less than20%(volume fraction)of Al2O3particles which weredeposited from powder mixtures with Ni/Al2O3mass ratios of4:1or higher.Moreover,mechanical and metallurgical bondings arethe main mechanisms of the adhesion of the coating to the Al substrate.Finally,functionally graded composite coatings withnoticeable compaction and integrity were produced by deposition of two separate layers under identical coating conditions.
基金This work was supported by the State Key Laboratory of Chemo/Biosensing and Chemometrics Foundation (No. 05-12-1), Fok-Yingtung Educational Foundation (No. 98-7-6) and Chongqing University Innovation Foundation of Science and Technology ( No. 06-1-1)
文摘6 Atomic fragment types of organic compound have been defined, and the multilevel atom-pair frequency matrix has been constructed according to the occurrence number in pairs of atomic fragments with different bond lengths in the molecule. On the basis of them, a novel molecular coding technique： characteristic atom-pair holographic code （CAHC）, is obtained. To some extent, this method exhibits a large number of benefits at the same time. For example, it can calculate 2D molecular topological descriptor easily, operate without difficulty and possess definite physicochemical meaning of 3D molecular structural characterization methods, and may fetch the complicated information of molecule, etc. Therefore, it is appropriate for the study on quantitative structure-property/activity relationship （QSPR/QSAR） of medicines and biological molecules. We attempt in this paper to utilize the method of CAHC to the quantitative prediction of reversed-phase liquid chromatogram （RPLC） retention data of 33 purine derivatives and 24 steroids. The fitting multiple correlation coefficient R2, cross-validated multiple correlation coefficient Q2 and predicted ability Q^2 pred over test set＇s samples of obtained partial least-square （PLS） regression model are respectively 0.990, 0.893 and 0.977, 0.897, 0.941.
基金Supported by the Natural Science Foundation of Jiangxi Province under Grant No 20133ACB20005the Key Program of National Natural Science Foundation of China under Grant No 41330318+3 种基金the Key Program of Science and Technology Research of Ministry of Education under Grant No NRE1515the Foundation of Training Academic and Technical Leaders for Main Majors of Jiangxi Province under Grant No 20142BCB22006the Research Foundation of Education Bureau of Jiangxi Province under Grant No GJJ14501the Engineering Research Center of Nuclear Technology Application(East China Institute of Technology)Ministry of Education under Grant NoHJSJYB2016-1
文摘For the frequency range of I kHz-lOMHz, the interface state density of Ni contacts on p-GaN is studied using capacitance-voltage （C-V） and conductance-frequency-voltage （G-f-V） measurements at room temperature. To obtain the real capacitance and interface state density of the Ni/p-GaN structures, the effects of the series resistance （Rs） on high-frequency （SMHz） capacitance values measured at a reverse and a forward bias are investigated. The mean interface state densities obtained from the CHF-CLF capacitance and the conductance method are 2 ×1012 e V-1 cm-2 and 0.94 × 1012 eV-1 cm-2, respectively. Furthermore, the interface state density derived from the conductance method is higher than that reported from the Ni/n-GaN in the literature, which is ascribed to a poor crystal quality and to a large defect density of the Mg-doped p-GaN.
基金supported by the NNSFC (21053001, 20701014)Fundamental Research Funds for the Central Universities (2009ZM0030 and student program)Undergraduate Research program of Guangdong
文摘A new polymeric iodoplumbate complex [Zn（DMF）6][Pb2I6] 1 has been prepared and characterized by elemental analysis and single-crystal X-ray analysis. Its structure contains infinite iodoplumbate chains constructed by the [PbI5] subunit. EHT crystal orbital calculation and the experimental results show that this material is an unconventional semiconductor and the electrical character is associated with its structural feature.
文摘The mono-α-nitronyl nitroxide substituted diacetylene was synthesized and its structure was established by EA,FAB-MS,IR,ESR and x-ray diffraction analysis.Using the Extracting Sample Magnetometer,its magnetic properties was investigated,and the results indicate that this compound possesses antiferromagnetic properties.
文摘A series of lanthanide complexes LnCl_3·L(Ln=La,Pr,Nd;L=15-C-5 or 18-C-6)have been synthesized and their molecular configuration,electronic structure and bond character have been studied by XPS and quantum chemical calculation.The calculated results are in good agreement with that obtained in the experiments.Three Cl atoms are on the same side of Ln in LnCl_3·15-C-5 and the crown ring on the other side.forming a complex molecule with coordination number 8.LnCl_3·15-C-5 is easily hygroscopic in air because of its unsaturated coordination,which differs sharply from the stable Ln(NO_3)_3·15-C-5 com- plex of coordination number 11.The HOMO and neighboring occupied MOs are composed of Cl 3p and O2p, and the LUMO and neighboring unoccupied MOs are composed of Ln orbitals.The level structure easily pro- duces Ln3d satellite in XPS caused by L→Ln charge transfer transition.Due to the coordination,the absolute values of the charge are decreased at Ln and O atoms,but increased at Cl atoms,which is in agreement with XPS results.
文摘In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2), c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is 0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism.
文摘Synthesis of complexes（η;-CH;C;H;）M（CO）;NO（M=Mo,I;M=W,II）and clusters（η;-CH;C;H;）M（μ;-NH）(μ;-NO) （μ;-CO）Fe;（CO）;（M=Mo,III:M=W,IV）,based on the reaction of （η;-C5;）M（CO）;Cl with Na[Fe（CO）;NO] at room tem-perature,have been demonstrated,The crystal structures of II and IV arealso presented.
基金supported by the National Natural Science Foundation of China(22379157)CAS Project for Young Scientists in Basic Research(YSBR-102)+2 种基金Institute of Coal Chemistry,Chinese Academy of Sciences(SCJC-XCL-2023-13,SCJCXCL-2023-10)Talent Projects for Outstanding Doctoral Students to Work in Shanxi Province(E3SWR4791Z)Fundamental Research Program of Shanxi Province(202403021222485).
文摘This data set collects,compares and contrasts the capacities and structures of a series of hard carbon materials,and then searches for correlations between structure and electrochemical performance.The capacity data of the hard carbons were obtained by charge/discharge tests and the materials were characterized by XRD,gas adsorption,true density tests and SAXS.In particular,the fitting of SAXS gave a series of structural parameters which showed good characterization.The related test details are given with the structural data of the hard carbons and the electrochemical performance of the sodium-ion batteries.
基金supported by the National Natural Science Foundation of China(32201994)。
文摘Sea buckthorn(Hippophae rhamnoides L.)is a natural homologous substance of medicine and food.Polysaccharide,as one of its primary active components,has very superior biological activity and can be used as a dietary supplement for functional foods,with good commercial prospects.Although initial progress has been made in the study of sea buckthorn polysaccharides,related studies have been fragmented and lacked systematic and generalization.This manuscript presents a critical analysis and systematic summary of the extraction and purification methods,structural characterization and physicochemical properties,biological activity and potential mechanisms,and structure-activity relationships of sea buckthorn polysaccharides.Accumulating evidence has indicated that sea buckthorn polysaccharides,which were widely prepared by water extraction and column chromatography purifications,exhibited exhibit superior biological activities in vitro and in vivo,including antioxidant,immunomodulatory,anti-inflammatory,hepatorenal protective,antibacterial,antiviral,and prebiotic activities.After analysis,it was concluded that there is a correlation between the relevant activities of sea buckthorn polysaccharides and that the structure of sea buckthorn polysaccharides has a great influence on their biological activity.We reviewed the challenges and limitations of sea buckthorn polysaccharides,summarized the critical aspects,and provided suggestions for potential breakthroughs in the research and application of sea buckthorn polysaccharide.
