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Microwave-assisted extraction of Shenfu coal and its macromolecule structure 被引量:13
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作者 CHEN Hong LI Jian,wei +1 位作者 LEI Zhao GE Ling-mei 《Mining Science and Technology》 EI CAS 2009年第1期19-24,共6页
Coals consist of some molecules trapped within an organic matrix from which some organic compounds can be extracted by solvents. The Soxhlet technique has been widely used for extracting organic compounds. Microwave h... Coals consist of some molecules trapped within an organic matrix from which some organic compounds can be extracted by solvents. The Soxhlet technique has been widely used for extracting organic compounds. Microwave heating methods may be successfully applied in the field of coal science. Acetone extraction yields and the chemical composition of the extract were investigated using a typical Chinese coal, Shenfu coal, with microwave-assisted extraction. The acetone extract and residue were analyzed by GC/MS and carbon-13 nuclear magnetic resonance spectroscopy respectively. The carbon spectra were converted into several numerical parameters, fa, Ha, Xb, which indicate the difference in macromolecular structure between Shenfu coal and its residue. Furthermore, a hybrid genetic algorithm was employed using these parameters to approximate a coal macromolecule by assembling the structural fragments or functional groups into a large and complicated structure. 展开更多
关键词 microwave-assisted extraction GC/M-S analysis carbon-13 nuclear magnetic resonance coal macromolecule structure
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BL19U2:Small-angle X-ray scattering beamline for biological macromolecules in solution at SSRF 被引量:4
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作者 Yi-Wen Li Guang-Feng Liu +4 位作者 Hong-Jin Wu Ping Zhou Chun-Xia Hong Na Li Feng-Gang Bian 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2020年第12期32-40,共9页
The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution.The beamline has been officially... The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution.The beamline has been officially opened to users in March 2015,and since then,a series of technological innovations has been developed to optimize beamline performance,thereby significantly improving the data collection efficiency and broadening the application scope of biological small-angle X-ray scattering.BL19U2 is ideal for the high-throughput screening of weakly scattered proteins,protein assemblies,nucleic acids,inorganic nanomaterials,and organic drug molecules.This paper describes the design and overview of the BL19U2 beamline.Versatile sample environments at the experimental station and some recent scientific highlights are presented. 展开更多
关键词 Shanghai synchrotron radiation facility Biological small-angle X-ray scattering High-throughput screening Biological macromolecules
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A Novel Method for Studying the interaction of Macromolecule with Small Molecule by Means of Affinity Capillary Electrophoresis 被引量:1
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作者 Met FANG Li SHENG +3 位作者 Hut Wan HAN Xiao YU Rut ZHAO Guo Quan LIU(Laboratory of Analytical Chemistry in Life Science, Institute of Chemistry, Chinese Academy ofSciences,Beijing 100080) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期235-238,共4页
A novel capillary electrophoresis method coupled with on-line microdialysis using an attachable electrode has been developed to study the interaction of macromolecule with small molecule. The binding constants of bovi... A novel capillary electrophoresis method coupled with on-line microdialysis using an attachable electrode has been developed to study the interaction of macromolecule with small molecule. The binding constants of bovine serum album (BSA) with D,L-tryptophan (Trp), sulfamethoxazole (SMZ) with trypsin and chymotrypsin were determined. These values are 2.3 x 10(4)L/mol for BSA-L-Trp; 1.77 x 10(3) L/mol for BSA-D-Trp in pH 7.4, 50 mmol/ L phosphate; 1.4 x 10(4) L/mol for SMZ- trypsin and 6.0 x 10(3) L/mol for SMZ-chymotrypsin in pH 6.5, 25 mmol/L Tris buffer. The proposed method has merits of speed, low sample consumption and readily available to be performed in desired physiological conditions. 展开更多
关键词 interaction of macromolecule with small molecule binding constant affinity capillary electrophoresis microdialysis membrane
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SYNTHESIS OF FUNCTIONAL MACROMOLECULE INTERMEDIATE THROUGH ACYLATION CATALYZED BY [Emim]Cl-AlCl_3 IONIC LIQUID 被引量:1
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作者 CHEN Min JIANG Deli +2 位作者 ZHANG Chunyan YU Long YAN Yongsheng 《Chinese Journal of Reactive Polymers》 2007年第1期15-21,共7页
Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer mate... Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer material, was obtained by recrystalling the reaction mixture with aether and was determined by GC/MS, 1↑HNMR and FTIR analysis. The influences of various parameters, such as the contents of AlCl3 in [Emim]Cl-AlCl3, the amount of acylation agent, amount of [Emim]Cl-AlCl3, reaction temperature and reaction time were investigated. The optimum conditions were as follows: the molar fraction of AlCl3 in ionic liquid [x(AlCl3)] being 0.67, molar ratio of ionic liquid to anthracene being 2:1, molar ratio of oxalyl chloride to anthracene being 2:1, reaction temperature being 40℃ and reaction time being 6h. Under above conditions, the yield and selectivity of 1,2-aceanthrylenedione can reach 91.5% and 98.3% respectively. Further more, [Emim]Cl-AlCl3 ionic liquid, compared with metal halides such as AlCl3, was found to catalyze the reaction as a novel environmental friendly catalyst and solvent and can be reused. 展开更多
关键词 Functional macromolecule intermediate Anthracene 1 2-aeanthrylenedione ACYLATION Ionic liauid.
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Metallated Schiff-Base Macromolecules as Alternative Metalloprotein Electron Transfer Intermediates
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作者 Al C. Farao Rachel Fanelwa Ayaji +1 位作者 Meryck Ward Priscilla GL Baker 《Journal of Surface Engineered Materials and Advanced Technology》 2020年第2期34-54,共21页
In the construction of biosensors, enzymes function as mediators converting biological signals generated by specific biological processes, into electrochemical signals. The ideology of bio-sensor design is retention o... In the construction of biosensors, enzymes function as mediators converting biological signals generated by specific biological processes, into electrochemical signals. The ideology of bio-sensor design is retention of electron transfer activity of the enzyme utilizing superior interfacial architecture. In this work a Schiff-base macromolecule has been synthesized by reflux of 2, 3-diaminonaphthalene and pyrrole-2-carboxaldehyde starting materials. The Schiff-base ligand was subsequently complexed with FeCl2?4H2O under reflux, to produce the Fe-Schiff-base complex. The Schiff-base ligand and Fe-Schiff-base complex were characterized using nuclear magnetic resonance (NMR) spectroscopy, Ultra Violet/Visible (UV/Vis) spectroscopy, Fourier transfer infrared resonance (FTIR) and electron energy loss spectroscopy (EELS) to confirm the structure of the synthesis products. NMR spectroscopy confirmed the imide linkage of Schiff-base formation as two symmetrical peaks at 8.1 and 7.7 ppm respectively. Comparison of starting materials and product spectra by UV/Vis spectroscopy confirmed the disappearance of the diaminonaphthalene peak at 250 nm as evidence of complete conversion to product. FTIR spectroscopy of the Schiff-base ligand confirmed the formation of the imine bond at 1595 cm-1. EELS spectra comparing FeCl2?4H2O and the Fe-Schiff-base complex, showed good agreement in the energy loss profiles associated with changes to the electronic arrangement of Fe d-orbitals. EDS clearly identified a spectral band for Fe (7 - 8 eV) in the Fe-Schiff-base complex. Electrochemical evaluation of the Fe-Schiff-base complex was compared to the electrochemical signature of denatured cytochrome-C using cyclic voltammetry and square wave voltammetry. The Fe2+/Fe3+ quasi-reversible behavior for iron in the metallated complex was observed at -0.430 V vs. Ag/AgCl, which is consistent with reference values for iron in macromolecular structures. 展开更多
关键词 CYTOCHROME-C macromolecule Metallated METALLOPROTEINS SCHIFF-BASE
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SYNTHESIS OF FUNCTIONAL MACROMOLECULE INTERMEDIATE THROUGH COUPLING REACTION CATALYZED BY [bmim]Cl/FeCl_3 IONIC LIQUID
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作者 CHEN Min CHEN Xiaonong +4 位作者 YUAN Xinhua ZHANG Yan ZHANG Chunyan LIU Hua DAI Qixun 《Chinese Journal of Reactive Polymers》 2006年第2期108-114,共7页
To obtain new functional aromatic polymer materiul. 3,3'-biacenaphthene, which is used as macromolecule intermediate of,funcrion aromatic polymer material, was synthesized through the coupling reaction of acenaphthen... To obtain new functional aromatic polymer materiul. 3,3'-biacenaphthene, which is used as macromolecule intermediate of,funcrion aromatic polymer material, was synthesized through the coupling reaction of acenaphthene catalyzing by ionic liquid ([bmim]CI/FeCl3) at mild reaction condition. Pure 3,3'-biacenaphthene was obtained hy recrystalling and column chromatography from the reaction mixture and was determined by GC/MS, SHNMR arid FTIR analysis. The influence of various reaction conditions on the yield of 3,3'-biacenaphthene were studied by GC analysis. The result shows that the optimun synthesis conditions of the coupling reaction are, as following: the molar ratio of FeCl3 to [BmimlCl being 3, the mole ratio of FeCl3 in [Bmim]Cl/FeCl3 to acenaphthene being 4. the reaction temperamre being 20 ℃ the reaction time being 4h and the solvent of the reaction system being PhNO2 Under those conditions, the yield of the 3.3'-biacenaphthene will be 48.71% and selectivity, of that will be 78.56 %. Farther more, [bmim]Cl/FeCl3 has no pollution to environments and can be reused. 展开更多
关键词 Functional macromolecule intermediate 3 3'-biacenaphthene Synthesis Coupling reactions Ionic liquid CATALYZE
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Inetetamab combined with pyrotinib and chemotherapy in the treatment of breast cancer brain metastasis: A case report
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作者 Qing-Qing Dou Ting-Ting Sun +1 位作者 Guo-Qiang Wang Wei-Bing Tong 《World Journal of Clinical Cases》 SCIE 2024年第3期575-581,共7页
BACKGROUND Breast cancer brain metastasis(BCBM)is an advanced breast disease that is difficult to treat and is associated with a high risk of death.Patient prognosis is usually poor,with reduced quality of life.In thi... BACKGROUND Breast cancer brain metastasis(BCBM)is an advanced breast disease that is difficult to treat and is associated with a high risk of death.Patient prognosis is usually poor,with reduced quality of life.In this context,we report the case of a patient with HER-2-positive BCBM treated with a macromolecular mAb(ine-tetamab)combined with a small molecule tyrosine kinase inhibitor(TKI).CASE SUMMARY The patient was a 58-year-old woman with a 12-year history of type 2 diabetes.She was compliant with regular insulin treatment and had good blood glucose control.The patient was diagnosed with invasive carcinoma of the right breast(T3N1M0 stage IIIa,HER2-positive type)through aspiration biopsy of the ipsilateral breast due to the discovery of a breast tumor in February 2019.Immunohistochemistry showed ER(-),PR(-),HER-2(3+),and Ki-67(55-60%+).Preoperative neoadjuvant chemotherapy,i.e.,the AC-TH regimen(epirubicin,cyclophosphamide,docetaxel-paclitaxel,and trastuzumab),was administered for 8 cycles.She underwent modified radical mastectomy of the right breast in November 2019 and received tocilizumab targeted therapy for 1 year.Brain metastasis was found 9 mo after surgery.She underwent brain metastasectomy in August 2020.Immunohistochemistry showed ER(-)and PR.(-),HER-2(3+),and Ki-67(10-20%+).In November 2020,the patient experienced headache symptoms.After an examination,tumor recurrence in the original surgical region of the brain was observed,and the patient was treated with inetetamab,pyrotinib,and capecitabine.Whole-brain radiotherapy was recommended.The patient and her family refused radiotherapy for personal reasons.In September 2021,a routine examination revealed that the brain tumor was considerably larger.The original systemic treatment was continued and combined with intensity-modulated radiation therapy for brain metastases,followed by regular hospitalization and routine examinations.The patient’s condition is generally stable,and she has a relatively high quality of life.This case report demonstrates that in patients with BCBM and resistance to trastuzumab,inetetamab combined with pyrotinib and chemotherapy can prolong survival.CONCLUSION Inetetamab combined with small molecule TKI drugs,chemotherapy and radiation may be an effective regimen for maintaining stable disease in patients with BCBM. 展开更多
关键词 Breast cancer brain metastasis Resistance to trastuzumab macromolecule inetetamab Small molecule tyrosine kinase inhibitor Radiation therapy HER2-positive Case report
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A Review on Graphene Oxide Two-dimensional Macromolecules: from Single Molecules to Macro-assembly 被引量:2
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作者 Wen-Zhang Fang Li Peng +3 位作者 Ying-Jun Liu Fang Wang Zhen Xu Chao Gao 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2021年第3期267-308,I0004,共43页
Graphene oxide(GO), which consists of two-dimensional(2 D) sp^(2) carbon hexagonal networks and oxygen-contained functional groups, has laid the foundation of mass production and applications of graphene materials. Ma... Graphene oxide(GO), which consists of two-dimensional(2 D) sp^(2) carbon hexagonal networks and oxygen-contained functional groups, has laid the foundation of mass production and applications of graphene materials. Made by chemical oxidation of graphite, GO is highly dispersible or even solubilized in water and polar organic solvents, which resolves the hard problem of graphene processing and opens a door to wet-processing of graphene. Despite its defects, GO is easy to functionalize, dope, punch holes, cut into pieces, conduct chemical reduction, form lyotropic liquid crystal, and assemble into macroscopic materials with tunable structures and properties as a living building block. GO sheet has been viewed as a single molecule, a particle, as well as a soft polymer material. An overview on GO as a 2 D macromolecule is essential for studying its intrinsic properties and guiding the development of relevant subjects. This review mainly focuses on recent advances of GO sheets, from single macromolecular behavior to macro-assembled graphene material properties. The first part of this review offers a brief introduction to the synthesis of GO molecules. Then the chemical structure and physical properties of GO are presented, as well as its polarity in solvent and rheology behavior. Several key parameters governing the ultimate stability of GO colloidal behavior, including size, p H and the presence of cation in aqueous dispersions, are highlighted. Furthermore, the discovery of GO liquid crystal and functionalization of GO molecules have built solid new foundations of preparing highly ordered, architecture-tunable, macro-assembled graphene materials, including 1 D graphene fibers, 2 D graphene films, and 3 D graphene architectures. The GO-based composites are also viewed and the interactions between these target materials and GO are carefully discussed. Finally, an outlook is provided in this field, where GO is regarded as macromolecules, pointing out the challenges and opportunities that exist in the field. We hope that this review will be beneficial to the understanding of GO in terms of chemical structure,molecular properties, macro-assembly and potential applications, and encourage further development to extend its investigations from basic research to practical applications. 展开更多
关键词 GRAPHENE 2D macromolecules Macro-assembly
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Behavior of macromolecules in adsorbed layers 被引量:1
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作者 牟伯中 姚恒申 罗平亚 《Science China Chemistry》 SCIE EI CAS 2000年第5期496-502,共7页
A model for describing the behavior of macromolecules in adsorbed layers is developed by introducing a concept of distribution density of layer thicknessU based on stochastic process and probabilistic statistics. The ... A model for describing the behavior of macromolecules in adsorbed layers is developed by introducing a concept of distribution density of layer thicknessU based on stochastic process and probabilistic statistics. The molecular behavior of layers adsorbed on clay particle surfaces is discussed; the random distribution and its statistics of the layer thickness are given by incorporating experimental results with an ionic polyelectrolyte with the molecular weight of 1.08 x 106and chain charged density of 0.254. 展开更多
关键词 macromolecule MOLECULAR BEHAVIOR of LAYER distribution DENSITY of thickness.
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Encoding of Primary Structures of Biological Macromolecules Within a Data Mining Perspective 被引量:1
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作者 MondherMaddouri MouradElloumi 《Journal of Computer Science & Technology》 SCIE EI CSCD 2004年第1期78-88,共11页
An encoding method has a direct effect on the quality and the representationof the discovered knowledge in data mining systems. Biological macromolecules are encoded by stringsof characters, called primary structures.... An encoding method has a direct effect on the quality and the representationof the discovered knowledge in data mining systems. Biological macromolecules are encoded by stringsof characters, called primary structures. Knowing that data mining systems usually use relationaltables to encode data, we have then to re-encode these strings and transform them into relationaltables. In this paper, we do a comparative study of the existing static encoding methods, that arebased on the Biologist know-how, and our new dynamic encoding one, that is based on the constructionof Discriminant and Minimal Substrings (DMS). Different classification methods are used to do thisstudy. The experimental results show that our dynamic encoding method is more efficient than thestatic ones, to encode biological macromolecules within a data mining perspective. 展开更多
关键词 encoding methods biological macromolecules data mining strings
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Macromolecules Mimicking Backbones of Nucleic and Teichoic Acids.Synthesis,Some Properties and Applications 被引量:1
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作者 Stanislaw Penczek Julia B.Pretula Krzysztof Kaluzynski 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2007年第5期557-558,共2页
1 Results Several methods have been elaborated in this laboratory allowing preparation of macromolecules with phosphodiester bonds,and having sequence of atoms similar as in the chains of biomacromolecules - nucleic o... 1 Results Several methods have been elaborated in this laboratory allowing preparation of macromolecules with phosphodiester bonds,and having sequence of atoms similar as in the chains of biomacromolecules - nucleic or teichoic acids (TA),namely:-(C)n-O-PO-,where n=2 (for teichoic acids) or 3.These methods,to be discussed in the lecture,are based on the ring-opening polymerization,transesterification,and recently elaborated direct addition of phosphoric acid to diepoxides.For the first time an attempt h... 展开更多
关键词 macromoleculeS teichoic acid mimicking backbones
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Diversity of culturable heterotrophic bacteria from the Mariana Trench and their ability to degrade macromolecules 被引量:6
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作者 Xiuxiu Zhao Jiwen Liu +4 位作者 Shun Zhou Yanfen Zheng Yanhong Wu Kazuhiro Kogure Xiao-Hua Zhang 《Marine Life Science & Technology》 2020年第2期181-193,共13页
The Mariana Trench is the deepest location on earth and harbors unique microbial communities as evidenced by 16S rRNA gene amplicon and metagenomic sequencing.Obtaining culturable microorganisms from the Mariana Trenc... The Mariana Trench is the deepest location on earth and harbors unique microbial communities as evidenced by 16S rRNA gene amplicon and metagenomic sequencing.Obtaining culturable microorganisms from the Mariana Trench will contribute to a further understanding of hadal biogeochemical processes and act as a unique microbial reservoir with potential applications.Here,825 bacterial strains,identified by 16S rRNA gene sequencing,were isolated from 12 water depths(0-10,400 m)of the Mariana Trench with 2216E and R2A media at 4℃ or 28℃ on four cruises during 2015-2017.These bacteria belong to four phyla,nine classes,27 orders,45 families and 108 genera.Alphaproteobacteria,Gammaproteobacteria,Actinobacteria_c,Bacilli and Flavobacteriia were the most abundant classes,accounting for 37.9%,33.0%,11.8%,8.6%and 8.0%of the total bacterial isolates,respectively.2216E and R2A media were found to have a better selectivity to Bacilli and Flavobacteriia,respectively.Fifty strains were potential novel bacterial species with a 16S rRNA gene similarity<98.65%,and a higher percentage of novel strains were obtained from R2A than 2216E medium.Additionally,301(150 species)out of 354 strains(178 species)selected from each depth could degrade at least one of the ten kinds of macromolecules tested.These results indicate that there is a high diversity of culturable bacteria in the Mariana Trench and they can produce a variety of extracellular enzymes.Our study provides a valuable resource of microorganisms for investigating their biogeochemical roles in the Mariana Trench and for industrial applications. 展开更多
关键词 DIVERSITY Heterotrophic bacteria The Mariana Trench macromolecule Water column
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A small molecule LS-1-2F promotes the endocytosis of macromolecules into tumor cells
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作者 Yanyan Yang Dengbo Ji +3 位作者 Simin Yang Siwang Yu Zhongjun Li Xiangbao Meng 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2019年第8期547-555,共9页
In the previous research, we found that anticancer agent LS-1-2 F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2 F on the endocytosis of macromolecules, including fluo... In the previous research, we found that anticancer agent LS-1-2 F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2 F on the endocytosis of macromolecules, including fluorescence quantum dots, human serum albumin, single-stranded RNA, and monoclonal antibody, into tumor cells. We found that LS-1-2 F could accelerate the endocytosis of these large molecules by laser confocal microscope and flow cytometry. The effect of LS-1-2 F on the improvement of the internalization efficiency of Herceptin biosimilar was particularly significant. Promoting endocytosis will help increase the efficiency of liquid-phase drug uptake in drug-resistant cancer cells and could potentially facilitate the use of drugs in nanoparticle delivery vehicles. 展开更多
关键词 Methuosis Macropinosomes Endocytosis of macromolecule Herceptin biosimilar
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Microorganism-derived biological macromolecules for tissue engineering
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作者 Naser Amini Peiman Brouki Milan +7 位作者 Vahid Hosseinpour Sarmadi Bahareh Derakhshanmehr Ahmad Hivechi Fateme Khodaei Masoud Hamidi Sara Ashraf Ghazaleh Larijani Alireza Rezapour 《Frontiers of Medicine》 SCIE CSCD 2022年第3期358-377,共20页
According to literature,certain microorganism productions mediate biological effects.However,their beneficial characteristics remain unclear.Nowadays,scientists concentrate on obtaining natural materials from live cre... According to literature,certain microorganism productions mediate biological effects.However,their beneficial characteristics remain unclear.Nowadays,scientists concentrate on obtaining natural materials from live creatures as new sources to produce innovative smart biomaterials for increasing tissue reconstruction in tissue engineering and regenerative medicine.The present review aims to introduce microorganism-derived biological macromolecules,such as pullulan,alginate,dextran,curdlan,and hyaluronic acid,and their available sources for tissue engineering.Growing evidence indicates that these materials can be used as biological material in scaffolds to enhance regeneration in damaged tissues and contribute to cosmetic and dermatological applications.These natural-based materials are attractive in pharmaceutical,regenerative medicine,and biomedical applications.This study provides a detailed overview of natural-based biomaterials,their chemical and physical properties,and new directions for future research and therapeutic applications. 展开更多
关键词 biological macromolecules regenerative medicine tissue engineering EXOPOLYSACCHARIDE CARBOHYDRATE
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Covalent Assembly of Penicillin Acylase in Mesoporous Silica Based on Macromolecular Crowding Theory 被引量:11
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作者 王安明 周成 +3 位作者 王华 沈树宝 薛建跃 欧阳平凯 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期788-790,共3页
To improve the covalent immobilization of penicillin acylase (PA), macromolecular crowding theory was applied to its immobilization. Influence of mass ratio of enzyme to the silica, as well as, activation time with ... To improve the covalent immobilization of penicillin acylase (PA), macromolecular crowding theory was applied to its immobilization. Influence of mass ratio of enzyme to the silica, as well as, activation time with glutaraldehyde on the activity of assembled PA, was studied. In the mesopores, the effect of fl-cyclodextrin (β-CD) on the immobilization of the enzyme was also investigated. It was remarkable that the coupled yield and relative activity reached 99.5% and 92.3%, respectively, when penicillin acylase assembled covalently in the mesopores. The results here indicate that mimicked macromolecule crowding could significantly ameliorate the performance of covalently immobilized PA. 展开更多
关键词 enzyme immobilization penicillin acylase Β-CYCLODEXTRIN macromolecule crowding
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Adsorption/desorption of toluene on a hypercrosslinked polymeric resin in a highly humid gas stream 被引量:6
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作者 Bing Zhou Bin Sun +4 位作者 Wenjuan Qiu Ying Zhou Junqian He Xiao'ai Lu Hanfeng Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第4期863-868,共6页
In many sources of volatile organic compounds (VOCs), large amounts of water vapor come from the air and the reactors. The relative humidity (RH) of exhaust gas is normally >60% and is supersaturated. Maintaining t... In many sources of volatile organic compounds (VOCs), large amounts of water vapor come from the air and the reactors. The relative humidity (RH) of exhaust gas is normally >60% and is supersaturated. Maintaining the property of adsorbent on VOCs in a highly humid gas stream is a serious industrial problem. In this study, the adsorption/desorption behavior of toluene in a micro-mesoporous polymeric resin was investigated in a highly humid environment to explore the influence of abound water vapor on resin adsorption and regeneration. This resin could selectively adsorb toluene at an RH of 80%, and its adsorption property was unaffected by the presence of water vapor. In the case of humidity saturation, the resin displayed a high adsorption capacity at a moisture content of <30%. Therefore, the polymer resin is an excellent water-resistant adsorbent of VOCs. In the regenerative experiment, the resin maintained its original adsorption capability after four adsorption/ desorption cycles of toluene purging with nitrogen gas at 120℃. The resin exhibited excellent regeneration performance at high humidity. 展开更多
关键词 ADSORPTION/DESORPTION VOLATILE organic compounds (VOCs) High humidity macromolecule RESIN
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Characterization of organic matter in total suspended particles by thermodesorption and pyrolysis-gas chromatography-mass spectrometry 被引量:4
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作者 ZHAO Jinping PENG Ping'an +3 位作者 SONG Jianzhong MA Shexia SHENG Guoying FU Jiarno 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第12期1658-1666,共9页
The organic matter in tropospheric aerosol plays an important role in atmospheric physical and chemical processes. The bulk of organic matter, representing a significant proportion of the total suspended particulate ... The organic matter in tropospheric aerosol plays an important role in atmospheric physical and chemical processes. The bulk of organic matter, representing a significant proportion of the total suspended particulate (TSP) mass, is bound to polymeric material whose structure and properties are largely unknown. Here we used thermodesorption gas chromatography/mass spectrometry (Td-GC/MS) to study organic compounds of low molecular mass and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) to characterize the chemical structure of macromolecules in TSP samples collected in different seasons from different sites in Guangzhou. n-Alkanes, fatty acids and nitriles were the predominant compounds in the thermodesorption products, whereas aromatics, fatty acids, nitriles and n-alkanes/alkenes were the major compounds in the pyrolysates. The results indicated that aromatics were main units in macromolecules. The fatty acids and nltriles formed from carboxylic ammonium salts were detected in both thermodesorption products and pyrolysates at a certain concentration, indicating the importance of these compounds in TSP formation. The TSP source mainly determined the occurrence of compounds in samples from urban, suburban and forest sites, whereas the TSP source and formation process maybe controlled the seasonal variation in compounds detected. High levels of nitriles in summer samples from suburban and forest sites coincide with the release of ammonium from the land and of fatty acids from vegetation at these sites. 展开更多
关键词 THERMODESORPTION pyrolysis total suspended particles organic matter macromolecule
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From crystalluria to kidney stones,some physicochemical aspects of calcium nephrolithiasis 被引量:4
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作者 Johannes M Baumann Beat Affolter 《World Journal of Nephrology》 2014年第4期256-267,共12页
Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in t... Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in the order of few minutes.Recently much work was done on rather qualitative aspects of nephrolithiasis like genetics,metabolism and morphology.In this review we try to provide some quantitative information on urinary supersaturation with respect to stone minerals,especially Ca oxalate(CaO x),on the formation and aggregation of Ca Ox crystals and on crystal retention in the kidney.The paper is centered on idiopathic Ca nephrolithiasis being the most frequent stone disease with only partially known pathogenesis.New aspects of the role of urinary macromolecules in stone formation and of the mechanism of crystal aggregation are provided. 展开更多
关键词 Calcium nephrolithiasis Crystalluria Crystal aggregation Urinary macromolecules Self aggregation
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Enrichment and immobilization of macromolecular analytes on a porous membrane utilizing permeation drag
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作者 Pedram Madadkar Rahul Sadavarte Raja Ghosh 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2018年第3期187-193,共7页
Enrichment and immobilization of analytes by chemical bonding or physical adsorption is typically the first step in many commonly used analytical techniques. In this paper, we discuss a permeation drag based technique... Enrichment and immobilization of analytes by chemical bonding or physical adsorption is typically the first step in many commonly used analytical techniques. In this paper, we discuss a permeation drag based technique as an alternative approach for carrying out location-specific immobilization of macro- molecular analytes. Fluorescein isothiocyanate (FITC) labeled macromolecules and their complexes were enriched near the surface of ultrafiltration membranes and detected by direct visual observation and fluorescence imaging. The level of macromolecule enrichment at the immobilization sites could be controlled by manipulating the filtration rate and thereby the magnitude of permeation drag. Higher enrichment as indicated by higher fluorescence intensity was observed at higher filtration rates. Also, larger macromolecules were more easily enriched. The feasibility of using this technique for detecting immunocomplexes was demonstrated by carrying out experiments with FITC labeled bovine serum al- bumin (FITC-BSA) and its corresponding antibody. This permeation drag based enrichment technique could potentially be developed further to suit a range of analytical applications involving more sophis- ticated detection methods. 展开更多
关键词 macromolecule ENRICHMENT IMMOBILIZATION Concentration polarization Permeation draglmmunoassay Membrane Ultrafiltration
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On the stochastic dynamics of molecular conformation
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作者 DENG Mao-lin ZHU Wei-qiu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第9期1401-1407,共7页
An important functioning mechanism of biological macromolecules is the transition between different conformed states due to thermal fluctuation. In the present paper, a biological macromolecule is modeled as two stran... An important functioning mechanism of biological macromolecules is the transition between different conformed states due to thermal fluctuation. In the present paper, a biological macromolecule is modeled as two strands with side chains facing each other, and its stochastic dynamics including the statistics of stationary motion and the statistics of conformational transition is studied by using the stochastic averaging method for quasi Hamikonian systems. The theoretical results are confirmed with the results from Monte Carlo simulation. 展开更多
关键词 Biological macromolecule Thermal fluctuation Stationary statistics Transition time Stochastic averaging method
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