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Synthesis and crystal structure characterization of yttrium imido complex:The reactivity of 2-substituted-1-amino-o-carborane with yttrium dialkyl complex
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作者 GUO Liping 《无机化学学报》 北大核心 2025年第7期1409-1415,共7页
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
关键词 yttrium imide O-CARBORANE synthesis structure characterization
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Structure characterization and immunoactivity on dendritic cells of two neutral polysaccharides from Dictyophora rubrovalvata
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作者 Ni Huang Yi-Na Yang +7 位作者 Jia Huang Hui-Yan Shao Yan-Lang Li Shi-Hui Qin Han-Fen Li Xiao-Jiang Shen Liu Yang Jiang-Miao Hu 《Natural Products and Bioprospecting》 CSCD 2024年第1期912-922,共11页
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
关键词 Dictyophora rubrovalvata POLYSACCHARIDES structure characterization Immunoactivity
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Optimization of Synthesis of Spherical Lignosulphonate Resin and Its Structure Characterization 被引量:3
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作者 范娟 詹怀宇 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第3期407-410,共4页
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
关键词 sphencal lignosulphonate resin process optimization structure characterization
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Micro-and Nano-structure Characterization of Isotropic Pyrocarbon Obtained via Chemical Vapor Deposition in Hot Wall Reactor
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作者 Kezhi Li,Dongsheng Zhang,Lingjun Guo and Hejun Li State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi an 710072,China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2010年第12期1133-1138,共6页
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 mi... 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 1.5 μm 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
关键词 Isotropic pyrocarbon Chemical vapor deposition structure characterization Onion-like pyrocarbon
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Effect of Limited Enzymatic Hydrolysis on Structure Characterization of Glycinin
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作者 Chunhong DUAN Wan SUN +2 位作者 Yunjie LI Yunlong WANG Siyi PAN 《Agricultural Biotechnology》 CAS 2012年第3期52-54,共3页
[ 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
关键词 GLYCININ Alkaline proteinase HYDROLYSIS structure characterization
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Bio-soft matter derived from traditional Chinese medicine:Characterizations of hierarchical structure,assembly mechanism,and beyond 被引量:4
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作者 Guiya Yang Yue Liu +4 位作者 Yuying Hu Yue Yuan Yunan Qin Quan Li Shuangcheng Ma 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期823-839,共17页
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
关键词 Electron microscopy SPECTROSCOPY Traditional Chinese medicine Bio-soft matter Structural characterization
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Prospects of sea buckthorn(Hippophae rhamnoides L.)polysaccharides:preparation,structural characterization,and bioactivities diversity
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作者 Shuyuan Shi Ruiyun Wu +4 位作者 Zixin Han Yu Sun Pinglan Li Fazheng Ren Nan Shang 《Food Science and Human Wellness》 2025年第1期11-28,共18页
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
关键词 Sea buckthorn POLYSACCHARIDES PREPARATION Structural characterization BIOACTIVITIES
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Panax notoginseng polysaccharides: a review focusing on the extraction, isolation, structural characterization, biological activities, and applications
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作者 Jiaqi Huang Yuheng Zhao +6 位作者 Mengyao Wang Xiaojin Tian Dianxin Cui Qilong Wang Xue Li Honghua Wu Wenzhi Yang 《Acupuncture and Herbal Medicine》 2025年第1期23-35,共13页
Panax notoginseng is a traditional Chinese medicine containing various constituents,including the saponins,polysaccharides,polyacetylenes,amino acids,etc.It has beneficial functions,such as the anti-inflammatory,antit... Panax notoginseng is a traditional Chinese medicine containing various constituents,including the saponins,polysaccharides,polyacetylenes,amino acids,etc.It has beneficial functions,such as the anti-inflammatory,antitumor,hepatoprotective,and anti-aging effects.Among these,P.notoginseng polysaccharides(PNPs)have been exploited because of their extensive pharmacological effects,being ranked as one of the current research hotspots,especially for the functional foods and medical practice.In this review,the literature related to PNPs in the past 20 years was surveyed and analyzed using both the China National Knowledge Infrastructure(CNKI)and Web of Science(WOS)databases.The visualization diagram shows that current studies on PNPs mainly focus on the antioxidant and immunomodulatory activities and structural characterization.In addition,the extraction,separation,purification,chemical analysis,structural characteristics,bioactivities,and applications of PNPs are outlined,in detail,aimed to provide valuable information for the further study,development,and utilization regarding PNPs. 展开更多
关键词 Biological activity EXTRACTION ISOLATION Panax notoginseng polysaccharides Structural characterization
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Structural characterization of blueberry fruit polysaccharides and assessment of its hypolipidemic and immunological activity
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作者 Chuyan Wang Yuqi Qin +4 位作者 Xiaoao Cui Dongsheng Wang Yexian Hu Liuqing Yang Wei Lan 《Food Science and Human Wellness》 2025年第4期1360-1368,共9页
In this study,polysaccharides were extracted from blueberry fruit(BFP)and isolated to 3 components(BFP-1,BFP-2 and BFP-3).The molecular weight,monosaccharide composition,characteristic groups,microscopic morphology,an... In this study,polysaccharides were extracted from blueberry fruit(BFP)and isolated to 3 components(BFP-1,BFP-2 and BFP-3).The molecular weight,monosaccharide composition,characteristic groups,microscopic morphology,and triple helical conformation of the polysaccharides were characterized using high performance permeation chromatography,high performance liquid chromatography,gas chromatographymass spectrometry,Fourier transform infrared spectrometer,scanning electron microscope and Congo red staining.Moreover,the hypolipidemic and immunological activities of the polysaccharides were also assessed.Results showed that the molecular weights of polysaccharides BFP-1,BFP-2,and BFP-3 were 5.547×10^(4),5.671×10^(4),and 3.951×10^(4)Da,respectively,the main monosaccharides were glucose(Glc),galactose(Gal)and arabinose(Ara),but BFP-3 was mainly composed of galacturonic acid(Gal A),Glc,Gal,and Ara.The backbone of BFP-1 was→4)-Glcp-(1→,which branches to Ara and xylose(Xyl)residues,while the backbone of BFP-2 was→5)-Araf-(1→,which branches to Xyl,Glc,rhamnose(Rha)and Gal residues,in particularly,BFP-3 has a more complex branching with a→3,6)-Galp-(1→)backbone,the side chain is dominated by Araf-(1→).Blueberry polysaccharides are pyran-type polysaccharides withα-glycosidic bonds,and BFP-1 has a typical triple-helical structure.The activity assay revealed that the binding of BFP-3 to sodium glycylcholate hydrate and sodium taurocholate was 79.95%and 78.50%,respectively,indicating that it had better hypolipidemic activity than the others.Immunoactivity assay showed that BFP promoted NO secretion through activating the NF-κB signalling pathway in RAW264.7 cells,which played a role in enhancing the immune function of the organism.These findings may provide a reference for the development and application of blueberry polysaccharides in functional food and medicine. 展开更多
关键词 Blueberry fruit polysaccharides Structural characterization HYPOLIPIDEMIC Immunological activity
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Solvothermal Synthesis and Characterization of [TM(1,2-dap)3]HgSb2Se5(TM = Co,Fe)with a Chain Structure 被引量:2
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作者 赵丽佳 赵日格吐 +1 位作者 韩文静 白音孟和 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第8期1222-1230,共9页
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
关键词 quaternary chalcogenidoantimonate solvothermal synthesis crystal structure characterization
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Recent progress in molten salt synthesis of low-dimensional perovskite oxide nanostructures, structural characterization,properties, and functional applications: A review 被引量:4
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作者 Piaojie Xue Heng Wu +1 位作者 Yao Lu Xinhua Zhu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第6期914-930,共17页
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
关键词 Low-dimensional perovskite nanostructures Molten salt synthesis Structural characterization Physical properties Functional applications
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A facile method for fabrication of nano-structured Ni-Al_2O_3 graded coatings: Structural characterization 被引量:1
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作者 Arash YAZDANI Taghi ISFAHANI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第1期77-87,共11页
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
关键词 metal matrix composite Ni-Al2O3 graded coating structural characterization
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Characterization of Interface State Density of Ni/p-GaN Structures by Capacitance/Conductance-Voltage-Frequency Measurements 被引量:1
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作者 Zhi-Fu Zhu He-Qiu Zhang +4 位作者 Hong-Wei Liang Xin-Cun Peng Ji-Jun Zou Bin Tang Guo-Tong Du 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第9期82-86,共5页
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
关键词 GaN characterization of Interface State Density of Ni/p-GaN structures by Capacitance/Conductance-Voltage-Frequency Measurements NI
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Characterization of Chilean hot spring-origin Staphylococcus sp.BSP3 produced exopolysaccharide as biological additive 被引量:1
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作者 Srijan Banerjee Gustavo Cabrera-Barjas +3 位作者 Jaime Tapia João Paulo Fabi Cedric Delattre Aparna Banerjee 《Natural Products and Bioprospecting》 CSCD 2024年第1期275-290,共16页
A type of high molecular weight bioactive polymers called exopolysaccharides(EPS)are produced by thermophiles,the extremophilic microbes that thrive in acidic environmental conditions of hot springs with excessively w... A type of high molecular weight bioactive polymers called exopolysaccharides(EPS)are produced by thermophiles,the extremophilic microbes that thrive in acidic environmental conditions of hot springs with excessively warm temperatures.Over time,EPS became important as natural biotechnological additives because of their noncytotoxic,emulsifying,antioxidant,or immunostimulant activities.In this article,we unravelled a new EPS produced by Staphy-lococcus sp.BSP3 from an acidic(pH 6.03)San Pedro hot spring(38.1℃)located in the central Andean mountains in Chile.Several physicochemical techniques were performed to characterize the EPS structure including Scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS),Atomic Force Microscopy(AFM),High-Performance Liquid Chromatography(HPLC),Gel permeation chromatography(GPC),Fourier Transform Infrared Spectroscopy(FTIR),1D Nuclear Magnetic Resonance(NMR),and Thermogravimetric analysis(TGA).It was confirmed that the amorphous surface of the BSP3 EPS,composed of rough pillar-like nanostructures,is evenly distributed.The main EPS monosaccharide constituents were mannose(72%),glucose(24%)and galactose(4%).Also,it is a medium molecular weight(43.7 kDa)heteropolysaccharide.NMR spectroscopy demonstrated the presence of a[→6)-α-d-Manp-(1→6)-α-d-Manp-(1→]backbone 2-O substituted with 1-α-d-Manp.A high thermal stability of EPS(287°C)was confirmed by TGA analysis.Emulsification,antioxidant,flocculation,water-holding(WHC),and oil-holding(OHC)capacities are also studied for biotechnological industry applications.The results demonstrated that BSP3 EPS could be used as a biodegradable material for different purposes,like flocculation and natural additives in product formulation. 展开更多
关键词 STAPHYLOCOCCUS Hot spring EXOPOLYSACCHARIDES Structural characterization FLOCCULATION Antioxidant activity
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A DIACETYLENE CONTAINING α-NITRONYL NITROXIDE——SYNTHESIS,CRYSTAL STRUCTURE AND MAGNETIC CHARACTERIZATION
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作者 De Qing ZHANG Wen Sheng ZhOU~a Dao Ben ZHU Institute of Chemistry,Academia Sinica,Beijing 100080 a.Dept,of Physics,Peking University,Beijing 100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第4期287-288,共2页
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
关键词 NITRONYL NITROXIDE SYNTHESIS CRYSTAL structure AND MAGNETIC characterization A DIACETYLENE CONTAINING
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STUDY ON SYNTHESIS,CHARACTERIZATION AND STRUCTURE OF A NEW RARE EARTH COORDINATION COMPOUND WITH BENZOIC ACID
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作者 段治邦 金钟声 +1 位作者 胡宁海 倪嘉缵 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期81-86,共6页
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
关键词 STUDY ON SYNTHESIS characterization AND structure OF A NEW RARE EARTH COORDINATION COMPOUND WITH BENZOIC ACID
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SYNTHESIS,CHARACTERIZATION AND CRYSTAL STRUCTURES OF η~5-CH_3C_5H_4)M(CO)_2NO AND(η~5-CH_3C_5H_4)M(μ_3-NH)(μ_2-NO)(μ_2-CO)Fe_2(CO)_6(M=Mo or W)
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作者 Wen Hua SUN Shi Yan YANG +1 位作者 Yuan Ci YIN Lanzhou Institute of Chemical Physics Chinese Academy of Sciences,Lanzhou 730000 Kai Bei YU Zhong Yuan ZHOU Chengdu Center of Analysis and Test Chinese Academy of Sciences,Chengdu 610015 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第3期263-266,共4页
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
关键词 Fe M=Mo or W CH3C5H4)M AND M SYNTHESIS characterization AND CRYSTAL structureS OF CO)Fe2 MO NO NH
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Structural characterization of three acidic polysaccharides from Opuntia dillenii Haw.fruits and their protective effect against hydrogen peroxide-induced oxidative stress in Huh-7 cells
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作者 Rui Liu Fangxin Chu +1 位作者 Zheng Yan Hanqing Chen 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1929-1942,共14页
Three novel acidic polysaccharide fractions(OFPP-1,OFPP-2,OFPP-3)with different m olecular weights(803.7,555.1 and 414.5 k Da)were isolated from the peeled Opuntia dillenii Haw.fruits by alkali-extraction,graded alcoh... Three novel acidic polysaccharide fractions(OFPP-1,OFPP-2,OFPP-3)with different m olecular weights(803.7,555.1 and 414.5 k Da)were isolated from the peeled Opuntia dillenii Haw.fruits by alkali-extraction,graded alcohol precipitation and column chromatography.Structural analysis indicated that OFPPs were pectic polysaccharides consisting of rhamnose,arabinose and galactose residues.The backbone of OFPP-1 consisted of a repeating unit→6-α-D-Galp A-(1→2)-α-L-Rhap-(1→with T-α-D-Galp A-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→,T-β-D-Xylp-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→or T-α-D-Galp A-(1→3)-α-L-Araf-(1→as the side chains.The backbone of OFPP-2 consisted of a disaccharide repeating unit→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→with T-β-L-Araf-(1→as the branches substituted at the O-4 position of→2,4)-α-LRhap-(1→.Whereas the backbone of OFPP-3 was→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-β-L-Araf-(1→or→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→,which was branched at the O-4 position of→2,4)-α-L-Rhap-(1→.Moreover,these three polysaccharide fractions could protect Huh-7 cells against H2O2-induced oxidative stress to different extents by decreasing the MDA content and increasing the SOD,CAT,GSH-Px activities and the GSH level in the Huh-7 cells.These results suggest that OFPPs have the potential to be used as natural antioxidants. 展开更多
关键词 Opuntia dillenii Haw.fruits POLYSACCHARIDE Alkali extraction Structural characterization Oxidative stress
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Structural characterization and anti-inflammatory activities of novel polysaccharides obtained from Pleurotus eryngii
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作者 Han Wang Sai Ma +5 位作者 Alfred Mugambi Mariga Qiuhui Hu Qian Xu Anxiang Su Ning Ma Gaoxing Ma 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期3031-3042,共12页
Natural polysaccharides named PEP-0.1-1,PEP-0-1 and PEP-0-2 from edible mushroom species Pleurotus eryngii were obtained in the present study.Results showed that molecular weights of these polysaccharides were 3235,20... Natural polysaccharides named PEP-0.1-1,PEP-0-1 and PEP-0-2 from edible mushroom species Pleurotus eryngii were obtained in the present study.Results showed that molecular weights of these polysaccharides were 3235,2041 and 23933 Da,respectively.Further,structural characterization revealed that PEP-0.1-1 had a→4-α-D-Glcp-1→backbone and contained→4)-α-D-Glcp and→4)-β-D-Glcp reducing end groups.PEP-0-1 backbone contained→4-α-D-Glcp-1→and→6-α-3-O-Me-D-Galp-1→,and the side chains containedα-D-Glcp,β-D-Manp-1→andα-D-Glcp-3→.However,PEP-0-2 backbone consisted of→4-α-DGlcp-1→and→6-α-3-O-Me-D-Galp-(1→6)-α-D-Galp-1→while the side chains containedα-D-Glcp andβ-D-Manp-1→.Biological activity analysis was then carried out and found that all these polysaccharides could significantly suppress the relative mRNA expression of toll-like receptor 4,nitric oxide(NO),tumor necrosis factor-α,interleukin(IL)-1βand IL-6 in lipopolysaccharide(LPS)-induced inflammation of RAW264.7 cells,as well as the over secretion of the above cell cytokines.Moreover,Western blotting analysis revealed that all these purified fractions displayed significant inhibition effects on the expression of c-Jun N-terminal kinases protein induced by LPS in mitogen activated protein kinase pathway,along with the relieving on the inhibition effect of LPS on IκB-αprotein expression.In summary,the information generated by the present study could provide a theoretical basis for the exploration of novel healthy food materials from edible mushroom with antiinflammation activities. 展开更多
关键词 Pleurotus eryngii POLYSACCHARIDES Structural characterization Anti-inflammatory activity
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Characterization of physicochemical and immunogenic properties of allergenic proteins altered by food processing:a review
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作者 Enning Zhou Qiangqiang Li +2 位作者 Dan Zhu Gang Chen Liming Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1135-1151,共17页
Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding epitopes.Understanding the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether ... Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding epitopes.Understanding the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce allergenicity.We here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic proteins.Detection techniques for characterizing changes in these properties of food allergens are summarized.Food processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new epitopes.Moreover,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food components.We provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile. 展开更多
关键词 Food allergens Protein structural characterization Immunogenicity evaluation Food processing modification
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