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Bio-soft matter derived from traditional Chinese medicine:Characterizations of hierarchical structure,assembly mechanism,and beyond
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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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Structure elucidation and in vitro rat intestinal fermentation properties of a novel sulfated glucogalactan from Porphyra haitanensis 被引量:3
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作者 Peilin Chen Lu Liu +4 位作者 Zirun Cheng Yi Zhang Baodong Zheng Xiaoke Hu Hongliang Zeng 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期596-606,共11页
This study was to investigate the structure and rat fecal microbial fermentation properties of a polysaccharide fraction(PHP2)isolated from the red marine alga Porphyra haitanensis.PHP2 was characterized as a sulfated... This study was to investigate the structure and rat fecal microbial fermentation properties of a polysaccharide fraction(PHP2)isolated from the red marine alga Porphyra haitanensis.PHP2 was characterized as a sulfated glucogalactan,with a hypothetical backbone structure of→4)Gα(1→6)G4 Sβ(1→4)Glc(1→and a side chain of Man(1→6)Glc.PHP2 had an irregular spherical chain conformation.The 16 S r RNA sequence analysis revealed that PHP2 modulated the rat fecal micro-flora composition,with a similar effect to inulin,changing the dominant genus(Lactobacillus and Escherichia-Shigella)and promoting the growth of organisms that degrade sulfur-containing polysaccharides,such as Desulfovibrio,Ruminococcaceae_UCG-005,and Ruminococcus_2.PHP2 can promote production of acetic,propionic and butyric acid by rat fecal micro-flora.Prediction of metabolic function suggested that PHP2 could modulate cholesterol metabolism.The sulfated glucogalactan fermentation behavior may be associated with its monosaccharide composition,chain branching and chain conformation.PHP2 appeared to have considerable potential as functional food,and was associated with sulfur-containing polysaccharides in general. 展开更多
关键词 Porphyra haitanensis structure characterization Fecal microflora Short-chain fatty acids Metabolic function prediction POLYSACCHARIDE
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Research Progress on Structure and Bioactivity of Longan Polysaccharide
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作者 Xiaolong Ji Shuli Zhang +5 位作者 Xueyuan Jin Xin Yuan Siqi Zhang Xudan Guo Fengcheng Shi Yanqi Liu 《Journal of Renewable Materials》 SCIE EI 2023年第4期1631-1642,共12页
Longan originates from southern China and has high nutritional and health value.Recent phytochemistry and pharmacology studies have shown that polysaccharides are a main bioactive component of longan.Longan polysaccha... Longan originates from southern China and has high nutritional and health value.Recent phytochemistry and pharmacology studies have shown that polysaccharides are a main bioactive component of longan.Longan polysaccharides possess antioxidant,anti-aging,anti-tumor,immunomodulatory,and other bioactivities.Hot-water extraction,ethanol precipitation,and ultrasonic extraction are generally used to extract water-soluble longan polysaccharides.However,the relationship between the structure and bioactivity of longan polysaccharides remains unclear,requiring further investigation.The aim of this review is to evaluate the current literature focusing on the extraction,purification,structural characterization,and biological activity of longan polysaccharides.We believe that this review would provide a useful bibliography for further innovation and a basis for using longan polysaccharides in functional food. 展开更多
关键词 LONGAN POLYSACCHARIDES structural characterization bioactivity
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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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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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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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Production, structure, and bioactivity of polysaccharide isolated from Tremella fuciformis 被引量:5
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作者 Hongjie Yuan Lin Dong +2 位作者 Zhiyuan Zhang Yan He Xia Ma 《Food Science and Human Wellness》 SCIE 2022年第4期1010-1017,共8页
Tremella fuciformis polysaccharide(TFP) is an important bioactive substance in T. fuciformis, which contributes to its application as medicine and food. In the present work, TFP was extracted with enzymatic combined w... Tremella fuciformis polysaccharide(TFP) is an important bioactive substance in T. fuciformis, which contributes to its application as medicine and food. In the present work, TFP was extracted with enzymatic combined with wet beating and its physicochemical as well as biological activities were investigated in the study. The result showed that the purity of TFP1 reached 92.14%(m/m). The TFP1, purified by DEAE column, had a molecular weight(Mw) of 5.8 × 10^(3) k Da and consisted mainly of mannose, xylose, fucose, glucose and glucuronic acid at a molar ratio of 1.91 : 0.1 : 2.49 : 6.23 : 0.95. The structure of TFP1 was preliminarily investigated by infrared spectroscopy, nuclear magnetic resonance and atomic force microscope(AFM) analysis. Moreover, the antioxidant assays showed that TFP1 could scavenge DPPH, ABTS+ and hydroxyl radicals. The excellent water holding capacity of TFP1 implied its application in the food, pharmaceutical andcosmetic industries. 展开更多
关键词 Tremella fuciformis polysaccharide structure characterization Antioxidant activity Moisturizing
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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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Study on the Quantitative Structure-toxicity Relationships for the Selected Esters by Using Molecular Electronegativity Interaction Vector (MEIV) 被引量:4
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作者 李建凤 廖立敏 王碧 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1225-1232,共8页
The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and p... The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and partial least-squares regression (PLS). The correlation coefficients (R) of the two models were 0.945 and 0.941, respectively. The models were evaluated by performing the cross validation with the leave-one-out (LOO) procedure. The cross-verification correlation coefficients (RCV) of the two models were 0.921 and 0.919, respectively. The results showed that the models constructed in this work could provide estimation stability and favorable predictive ability. 展开更多
关键词 ESTERS tetrahymena pyriformis half-inhibitory growth concentration (IGC50) structural characterization quantitative structure toxicity relationship (QSTR)
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Effects of High-voltage Pulse Electric Field Treatment on the Structure Stability of Konjac Glucomannan 被引量:3
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作者 姚闽娜 范琳琳 +4 位作者 刘雅楠 陈清爱 曾援 简文杰 庞杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第12期1833-1837,共5页
Structures of KGM treated in two high-voltage pulse electric fields were characterized by infrared spectroscopy,Raman spectroscopy,X-ray diffraction and so on.The results showed that intermolecular hydrogen bonding in... Structures of KGM treated in two high-voltage pulse electric fields were characterized by infrared spectroscopy,Raman spectroscopy,X-ray diffraction and so on.The results showed that intermolecular hydrogen bonding interactions of KGM were reduced after being treated with high-voltage pulse electric field,but there was no significant effect on its fiber chain form and thermal characteristics.Results of the study can provide a useful reference for further study on the structure and property of KGM,and especially can provide theoretical basis for the effect of physical field on the foodstuff deep processing related to KGM. 展开更多
关键词 KGM structural characterization high-voltage pulse electric field STABILITY
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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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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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Studies on a Novel Characteristic Atom-pair Holographic Code Applied to Quantitative Structure-chromatographic Retention Relationship of Organic Compounds 被引量:1
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作者 ZHOU Peng TIAN Fei-Fei +1 位作者 WANG Jiao-Na LI Zhi-Liang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第11期1337-1342,共6页
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
关键词 characteristic atom-pair holographic code quantitative structure-chromatographic retention relationship characterization of molecular structure partial least-square regression
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EFFECTS OF CHAIN STRUCTURE OF POLYPYRROLONES ON THE ELECTRICAL PROPERTIES OF PYROLYZED POLYPYRROLONES
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作者 朴明俊 万梅香 卢凤才 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第1期74-83,共10页
Three kinds of polypyrrolones (PMDA-DAB, PMDA-TADPE and DEDA-DAB) were pyrolyzed at high temperature in order to study the effect of the chain structure of polypyrrolones on the electrical properties of the pyrolyzed ... Three kinds of polypyrrolones (PMDA-DAB, PMDA-TADPE and DEDA-DAB) were pyrolyzed at high temperature in order to study the effect of the chain structure of polypyrrolones on the electrical properties of the pyrolyzed polymers. Results show that the number of fusing rings in the main chain of polymers has a little effect on the pyrolysis process, whereas, the ether bond in the main chain plays an important role during pyrolysis. Structure characterizations by elemental analysis, XPS spectra, X-ray diffraction and SEM images indicate that because the ether bond is easy to break, it is difficult to form large area planar network. This hampers the formation of the graphite-like structure in the polypyrrolones containing ether bond even after being pyrolyzed at 1200 degrees C. 展开更多
关键词 polypyrrolones PYROLYSIS electrical properties structure characterizations
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Annealing behaviour of structure and morphology and its effects on the optical gain of Er^3+/yb^3+ co-doped Al2O3 planar waveguide amplifier
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作者 谭娜 张庆瑜 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期2165-2169,共5页
Using transmission electron microscopy (TEM) and x-ray diffraction analysis, we have studied the structural and morphological evolution of highly Er/Yb co-doped A1203 films in the temperature range from 600℃-900℃.... Using transmission electron microscopy (TEM) and x-ray diffraction analysis, we have studied the structural and morphological evolution of highly Er/Yb co-doped A1203 films in the temperature range from 600℃-900℃. By comparison with TEM observation, the annealing behaviours of photoluminescence (PL) emission and optical loss were found to have relation to the structure and morphology. The increase of PL intensity and optical loss above 800℃ might result from the crystallization of amorphous Al2O3 films. Based on the study on the structure and morphology, a rate equation propagation model of a multilevel system was used to calculate the optical gains of Er-doped Al2O3 planar waveguide amplifiers involving the variation of PL efficiency and optical loss with annealing temperature. It was found that the amplifiers had an optimized optical gain at the temperature corresponding to the minimum of optical loss, rather than at the temperature corresponding to the maximum of PL efficiency, suggesting that the optical loss is a key factor for determining the optical gain of an Er-doped Al2O3 planar waveguide amplifier. 展开更多
关键词 Er-doped waveguide amplifier annealing behaviour structural characterization optical gain
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The Effect of Spatial Structure Character of Heat Source on the Ray Path and the Evolution of Wave Energy of Meridional Wave Train
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作者 徐祥德 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第1期87-98,共12页
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
关键词 The Effect of Spatial structure Character of Heat Source on the Ray Path and the Evolution of Wave Energy of Meridional Wave Train PATH Wave
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Structure and Semiconducting Character of a Polymeric Iodoplumbate Coordination Complex
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作者 宋德生 刘长春 +2 位作者 陈恒隽 苏东坡 傅志勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第8期1142-1146,共5页
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
关键词 iodoplumbate coordination polymer structure and characterization semiconducting property
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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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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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ELECTRONIC STRUCTURE AND BOND CHARACTER OF COMPLEXES OF RARE EARTH CHLORIDES WITH CROWN ETHERS
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作者 李振祥 周清廉 +5 位作者 胡宁海 倪嘉缵 任镜清 黎乐民 赵井泉 徐光宪 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第4期241-245,共5页
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
关键词 ELECTRONIC structure AND BOND CHARACTER OF COMPLEXES OF RARE EARTH CHLORIDES WITH CROWN ETHERS CI THAN
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