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Visual Evaluation of the Morphologic Structure of Nonwovens Using Image Analysis and Fractal Geometry 被引量:1
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作者 杨旭红 李栋高 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期162-165,共4页
Nonwovens are fiber materials which are based on nonwoven technologies. For the complexity and randomness of nonwovens morphologic structures, it is difficult to express them effectively using classical method. Fracta... Nonwovens are fiber materials which are based on nonwoven technologies. For the complexity and randomness of nonwovens morphologic structures, it is difficult to express them effectively using classical method. Fractal geometry gives us a new idea and a powerful tool to study on irregularity of geometric objects. Therefore, we studied on the pore size, pore shape, pore size distribution and fiber orientation distribution of real nonwovens using fractal geometry combined with computer image analysis to evaluate nonwovens’ morphologic structures. 展开更多
关键词 NONWOVENS morphologic structure fractal geometry image analysis
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A Morphologically Structured Model for Mycelial Growth and Secondary Metabolite Formation 被引量:12
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作者 刘刚 徐志南 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第1期46-51,共6页
A morphologically structured model is proposed to describe the batch fermentation of lovastatin according to the growth kinetics of filamentous microorganisms. Three kinds of hyphae are considered in the model: active... A morphologically structured model is proposed to describe the batch fermentation of lovastatin according to the growth kinetics of filamentous microorganisms. Three kinds of hyphae are considered in the model: actively growing hyphae, non-growing hyphae and deactivated hyphae. Furthermore, actively growing hyphae consist of three morphological compartments: apical compartment which gives rise to hyphal tip extension; subapical compartment which is related to hyphal branching; and hyphal compartment which is only responsible for secondary metabolite formation. The kinetics of mycelial growth mechanism is summarized and applied in modeling lovastatin fermentation. A Michaelis-Menten kinetic model with substrate inhibition is proposed for product formation. As expected, the model simulations fit well with experimental data obtained either from a laboratory scale 10L fer-menter or from a pilot-plant scale fermenter. 展开更多
关键词 LOVASTATIN Aspergillus terreus filamentous microorganism morphologically structured model KINETICS
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Morphological Structure and Genetic Mapping of New Leaf-Color Mutant Gene in Rice (Oryza sativa) 被引量:7
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作者 LI Yu-hong WANG Bao-he +5 位作者 DAI Zheng-yuan LI Ai-hong LIu Guang-qing Zuo Shi-min ZHANG Hong-xi PAN Xue-biao 《Rice science》 SCIE 2012年第2期79-85,共7页
Leaf-color mutations are a widely-observed class of mutations, playing an important role in the study of chlorophyll biosynthesis and plant chloroplast structure, function, genetics and development. A naturally-occurr... Leaf-color mutations are a widely-observed class of mutations, playing an important role in the study of chlorophyll biosynthesis and plant chloroplast structure, function, genetics and development. A naturally-occurring leaf-color rice mutant, Baihuaidao 7, was analyzed. Mutant plants typically exhibited a green-white-green leaf-color progression, but this phenotype was only expressed in the presence of a stress signal induced by mechanical scarification such as transplantation. Prior to the appearance of white ~eaves, mutant plant growth, leaf color, chlorophyll content, and chloroplast ultrastructure appeared to be identical to those of the wild type. After the changeover to white leaf color, an examination of the mutated leaves revealed a decrease in total chlorophyll, chlorophyll a, chlorophyll b, and carotenoid content, a reduction in the number of chloroplast grana lamella and grana, and a gradual degradation of the thylakoid lamellas. At maturity, the mutant plant was etiolated and dwarfed compared with wild-type plants. Genetic analysis indicated that the leaf mutant character is controlled by a recessive nuclear gene. Genetic mapping of the mutant gene was performed using an F2 population derived from a Baihuaidao 7 ~ Jiangxi 1587 cross. The mutant gene was mapped to rice chromosome 11, positioned between InDel markers L59.2-7 and L64.8-11, which are separated by approximately 740.5 kb. The mutant gene is believed to be a new leaf-color mutant gene in rice, and is tentatively designated as gwgl. 展开更多
关键词 Oryza sativa leaf-color mutant morphological structure genetic analysis gene mapping
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EFFECT OF STRESS-INDUCED REACTIONS ON MORPHOLOGICAL STRUCTURE AND PROCESSABILITY OF PVC DURING PAN-MILLING 被引量:1
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作者 Hua-weiZou WenXu Qing-fenFeng XiXu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第2期227-234,共8页
The effect of pan-milling on morphological structure,processability and properties of PVC was studied throughSEM,FTIR,granulometer,GPC and mechanical properties test in the hope of gaining ease in operation,needless o... The effect of pan-milling on morphological structure,processability and properties of PVC was studied throughSEM,FTIR,granulometer,GPC and mechanical properties test in the hope of gaining ease in operation,needless ofplasticizers,a clean and efficient route for improving the processability of PVC through stress-induced reactions,fulfilling the idea of“plasticizing PVC by itself”.The experimental results show that during pan-milling at ambienttemperature,within 2-3 min,the microcrystalline structure of PVC becomes indistinct,the grain size of PVC is reducedfrom 130-160 μm to 1-50 μm the molecular weight of PVC is slightly decreased,the variation of molecular weightdistribution is indistinct,the plasticizing time and torque at balance drop a great deal from 71-132 s to 31-33 s and from18.2-22.1 Nm to 14.7-18.4 Nm,respectively,the processability of PVC is markedly improved,and the mechanicalproperties get enhanced too. 展开更多
关键词 Poly(vinyl chloride) Stress-induced reaction morphological structure Processability.
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EFFECT OF MORPHOLOGICAL STRUCTURE OF AMINOMETHYL POLYSTYRENE RESIN ON THE CATALYTIC PROPERTIES OF POLYMERSUPPORTED RUTHENIUM COMPLEXES
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作者 雷自强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第1期93-100,共8页
Polymer-supported ruthenium complexes ■-Phen-Ru-①,■-Phen-Ru-②,■-Phen-Ru-③,■-Phen-Ru-④, ■-Phen-Ru-⑤,■-Phen-Ru-⑥and ■-Phen-Ru-⑦were prepared using aminomethyl polystyrenes of different morphological struct... Polymer-supported ruthenium complexes ■-Phen-Ru-①,■-Phen-Ru-②,■-Phen-Ru-③,■-Phen-Ru-④, ■-Phen-Ru-⑤,■-Phen-Ru-⑥and ■-Phen-Ru-⑦were prepared using aminomethyl polystyrenes of different morphological structures as supports.A variety of alcohols were oxidized efficiently into the corresponding ketones, carboxylic acids or aldehydes with iodosylbenzene (PhIO) catalyzed by aminomethyl polystyrene-supported ruthenium complexes under mild reaction conditions in acetonitrile.The influences of morphological structure... 展开更多
关键词 Alcohol oxidation Ru-immobilized catalyst PS-carrier morphological structure
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A Population Morphologically Structured Model for Microscopic Growth of Filamentous Microorganism
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作者 刘刚 徐志南 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第3期252-262,共11页
The growth of filamentous microorganism is contributed by tip extension and branching. The microscopic growth of filamentous microorganism means the growth process from one or a few spores. In order to describe the mi... The growth of filamentous microorganism is contributed by tip extension and branching. The microscopic growth of filamentous microorganism means the growth process from one or a few spores. In order to describe the microscopic process, a population morphologically structured model is proposed, in which three morphological compartment and their interactions were considered, and the heterogeneity of hyphal growth was included. The model was applied to describe the microscopic growth of Streptomyces tendae and Geotrichum candidum with good agreement. From model prediction, it is concluded that if the number of hyphae is large enough (macroscopic growth), the specific growth rate of filamentous microorganism and the ratio of morphological forms in hyphae will become constant. 展开更多
关键词 population morphologically structured model filamentous microbe Streptomyces tendae Geotrichum candidum
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MISCIBILITY AND MORPHOLOGICAL STRUCTURE OF BIODEGRADABLE BLEND OF POLY(β—HYDROXYBUTYRATE)AND POLY(D,L—LACTIDE)
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作者 Xian Mo DENG Lian Lai ZHANG Chengdu Institute of Organic Chemistry,Academia Sinica Chengdu 610041 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期269-272,共4页
The poly(β-hydroxybutyrate)/poly(d,1-lactide)(PHB/PLA)blend was found to be immiscible,the melting point and the phase crystallinity of PHB were independent of the blend composition.Comparing with plain PHB,the blend... The poly(β-hydroxybutyrate)/poly(d,1-lactide)(PHB/PLA)blend was found to be immiscible,the melting point and the phase crystallinity of PHB were independent of the blend composition.Comparing with plain PHB,the blend exhibited the crystallization change and a certain improvement of the mechanical property. 展开更多
关键词 PHB MISCIBILITY AND morphologicAL structure OF BIODEGRADABLE BLEND OF POLY HYDROXYBUTYRATE)AND POLY LACTIDE D L
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SYNTHESIS AND MORPHOLOGICAL STRUCTURE OF POLY (PHENYLENE SULFIDE AMIDE)
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作者 伍齐贤 陈永荣 周祚万 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1995年第2期136-143,共8页
Poly(phenylene sulfide amide) (PPSA) has been synthesized by using sulfur as S source which reacts with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure. The polymer structures ... Poly(phenylene sulfide amide) (PPSA) has been synthesized by using sulfur as S source which reacts with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure. The polymer structures were determined by elemental analysis, FT-IR and H-1-NMR. It is shown that the yielded polymer has linear structure and its structure unit is -p-C6H4-CONH -p-C6H4-S-. The polymer morphology was studied by X-ray diffraction and polarized microscopy. The results show that PPSA is a crystalline polymer and its spherulites are the aggregation of nontwisting lamella or micro-thread structure. Under shearing force, these crystals are dispersed to form micro-fibrillar structure. The decomposition kinetics of PPSA was also studied at different heating rates. The decomposition energy of PPSA is higher than that of PPS. 展开更多
关键词 POLYARYLENE SULFIDE POLY (PHENYLENE SULFIDE AMIDE) SYNTHESIS morphologicAL structure
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Effect of Cryopreservation on DNA Integrity and Morphological Structure of Boar Sperm
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作者 Yang Jianping Wu Caihong +4 位作者 Zhao Xuting Zhou Chunbao Yao Jing Zhang Bin Zheng Xiaofeng 《Animal Husbandry and Feed Science》 CAS 2014年第6期325-327,共3页
The paper was to explore the effect of cryopreservation on DNA integrity and morphological structure of boar sperm, and to explore the protective effect of trehalose and lactose on frozen boar sperm. The morphology, u... The paper was to explore the effect of cryopreservation on DNA integrity and morphological structure of boar sperm, and to explore the protective effect of trehalose and lactose on frozen boar sperm. The morphology, ultrastructure and DNA integrity of sperms were observed by phase contract microscope, scanning electron microscope (SEM) and acridine orange (AO) staining, respectively. The results showed that the normal morphological rate and DNA integrity rate of fro- zen sperms were significantly lower than that of fresh sperms (95.5% and 94.7%, respectively), and the difference between two frozen groups was also significant (P 〈 0.05 ). The normal morphological rates in trehalose group and lactose group were 74.7% and 67.6%, while DNA integrity rates in trehalose group and lactose group were 66.4% and 63.2%, respectively. The common deformations of frozen sperms under SEM were partial or complete fracture between head and neck, swollen neck_ dama=ed aemsome stnJetn~. 展开更多
关键词 Boar sperm CRYOPRESERVATION DNA morphological structure
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Advances in Research of Relationship between Morphological Structure and Yield of Castor
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作者 Hailin WEI Xumeng LI +2 位作者 Xiaohui WANG Jun YANG Huang HUANG 《Medicinal Plant》 CAS 2020年第5期1-7,共7页
Castor is a cash crop with very wide adaptability in China,and its yield is closely related with its morphological structure.With reference to the research on the relationship between the morphological structure and y... Castor is a cash crop with very wide adaptability in China,and its yield is closely related with its morphological structure.With reference to the research on the relationship between the morphological structure and yield of main cash crops such as rice,wheat and maize,this paper made a review of advances in the research of the relationship between castor variety characteristics,habitat conditions,dry matter distribution,cultivation measures.Finally,it present the research direction,content and route of the relationship between the morphological structure and yield of the castor in the future. 展开更多
关键词 CASTOR morphological structure YIELD
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Structural,Morphological and Electrical Properties of In-Doped Zinc Oxide Nanostructure Thin Films Grown on p-Type Gallium Nitride by Simultaneous Radio-Frequency Direct-Current Magnetron Co-Sputtering
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作者 R.Perumal Z.Hassan R.Saravanan 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期77-80,共4页
Zinc oxide (ZnO) is one of the most promising and frequently used semiconductor materials. In-doped nanos- tructure ZnO thin films are grown on p-type gallium nitride substrates by employing the simultaneous rf and ... Zinc oxide (ZnO) is one of the most promising and frequently used semiconductor materials. In-doped nanos- tructure ZnO thin films are grown on p-type gallium nitride substrates by employing the simultaneous rf and dc magnetron co-sputtering technique. The effect of In-doping on structural, morphological and electrical properties is studied. The different dopant concentrations are accomplished by varying the direct current power of the In target while keeping the fixed radio frequency power of the ZnO target through the co-sputtering deposition technique by using argon as the sputtering gas at ambient temperature. The structural analysis confirms that all the grown thin films preferentially orientate along the c-axis with the wurtzite hexagonal crystal structure without having any kind of In oxide phases. The presenting Zn, 0 and In elements' chemical compositions are identified with EDX mapping analysis of the deposited thin films and the calculated M ratio has been found to decrease with the increasing In power. The surface topographies of the grown thin films are examined with the atomic force microscope technique. The obtained results reveal that the grown film roughness increases with the In power. The Hall measurements ascertain that all the grown films have n-type conductivity and also the other electrical parameters such as resistivity,mobility and carrier concentration are analyzed. 展开更多
关键词 ZnO of Structural morphological and Electrical Properties of In-Doped Zinc Oxide Nanostructure Thin Films Grown on p-Type Gallium Nitride by Simultaneous Radio-Frequency Direct-Current Magnetron Co-Sputtering that by were been In EDX on
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Inheritance of the Anatomy--Morphological Structure of the Stalk by Interspecific Hybrids of the Glycine L.
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作者 Margarita Kozak 《Journal of Life Sciences》 2014年第9期768-774,共7页
The research focuses on the study of anatomical and morphological stalk structure ofsoya interspecific hybrids of the third generation (F3) between (Glycine max (L.) Merr.) and G. soja Sieb. et Zucc. in comparis... The research focuses on the study of anatomical and morphological stalk structure ofsoya interspecific hybrids of the third generation (F3) between (Glycine max (L.) Merr.) and G. soja Sieb. et Zucc. in comparison with parent plant species. The parent plant species and interspecific hybrids were sowed and grew under similar conditions. The similarity of the anatomic structure of stalks of cultivated plants and Glycine soja (wild soya) proves the hypothesis the studied species have the same origin. However, the obtained results show the considerable degree of phylogenetic dissociation between the studied soya species. Interspecific hybrids inherit from G. soja the ability to high intensive growth. The G. soja use in practical selective breeding is of great interest. 展开更多
关键词 Plant breeding and genetics plant morphology and structure Glycine max Glycine soja (wild soya) interspecific hybrid anatomic and morphological stalk.
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Fabrication and characterization of multi-scale coated boron powders with improved combustion performance:A brief review 被引量:1
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作者 Rui Liu Danfeng Yang +2 位作者 Kunyu Xiong Ying-Lei Wang Qi-Long Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期27-40,共14页
Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion efficiency.This literature review summarizes the strategies that are used to solve the above-mentioned problems,whic... Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion efficiency.This literature review summarizes the strategies that are used to solve the above-mentioned problems,which include coatings of boron by using fluoride compounds,energetic composites,metal fuels,and metal oxides.Coating techniques include recrystallization,dual-solvent,phase transfer,electrospinning,etc.As one of the effective coating agents,the fluorine compounds can react with the oxide shell of boron powder.In comparison,the energetic composites can effectively improve the flame temperature of boron powder and enhance the evaporation efficiency of oxide film as a condensed product.Metals and metal oxides would react with boron powder to form metal borides with a lower ignition point,which could reduce its ignition temperature. 展开更多
关键词 Boron powder coating structure and morphology Condensed phase thermal reaction Ignition and combustion
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Optimization and Characterization of Combined Degumming Process of Typha angustata L. Stem Fibers
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作者 Sana Rezig Foued Khoffi +2 位作者 Mounir Jaouadi Asma Eloudiani Slah Msahli 《Journal of Renewable Materials》 EI CAS 2024年第6期1071-1086,共16页
Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to... Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to study their physical,chemical,and mechanical properties.In this context,the present study relates to the extraction,characterization,and optimization of Typha angustata L.stem fibers.For this purpose,desirability functions and response surface methodology were applied to simultaneously optimize the diameter(D),linear density(LD);yield(Y),lignin fraction(L),and tenacity(T)of Typha stem fibers.Typha stems have been subjected to both alkali(NaOH)and enzymatic(pectinex ultra-SPL)treatments.Three levels of process variables including enzyme concentration(10,15,and 20 ml/L)and treatment duration(10,15,and 20 days)were used to design the experiments according to the factorial design.Experimental results were examined by analysis of variance and fitted to second order polynomial model using multiple regression analysis.The Derringer’s desirability function released that the values of process variables generating optimized diameter,linear density,yield,lignin ratio and tenacity are 20 ml/L and 20 days for concentration of pectinex ultra-SPL enzyme and treatment duration,respectively.Confirmation was performed and high degree of correlation was found between the experimental and statistical values.Moreover,the morphological structure has been investigated by the scanning electron microscope,showing a crenelated structure of ultimate fiber bundles of cellulose composing the Typha fiber.Compared to Typha stem non-treated fibers(TSNTF),Typha stem combined treated fibers(TSCTF),brings to improve mechanical properties.This change in mechanical properties is affected by modifying the fiber structure showing alpha cellulose of(66.86%)and lignin ratio of(10.83%)with a crystallinity index of(58.47%). 展开更多
关键词 Typha angustata L.stems fibers combined treatment optimization process desirability function chemical and physical properties morphological structure
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INVESTIGATION OF STRUCTURE AND PROPERTIES FOR POLYMER SYSTEMS BASED ON DYNAMIC RHEOLOGICAL APPROACHES 被引量:6
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作者 郑强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第4期341-354,共14页
The dynamic rheological measurements have been a preferred approach to the characterization of the structure and properties for multi-component or multi-phase polymer systems,due to its sensitive response to changes o... The dynamic rheological measurements have been a preferred approach to the characterization of the structure and properties for multi-component or multi-phase polymer systems,due to its sensitive response to changes of structure for these heterogeneous polymers.In the present article,recent progresses in the studies on dynamic rheology for heterogeneous polymer systems including polymeric composites filled with inorganic particles,thermo-oxidized polyolefins,phase- separated polymeric blends and functional polymers with the scaling and percolation behavior are reviewed,mainly depending on the results by the authors' group.By means of rheological measurements,not only some new fingerprints responsible for the evolution of morphology and structure concerning these polymer systems are obtained,the corresponding results are also significant for the design and preparation of novel polymer-based composites and functional materials. 展开更多
关键词 Heterogeneous polymers Dynamic rheological properties PHASE-SEPARATION Morphology and structure Scaling and percolation behavior
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STUDIES ON STRUCTURE AND PHASE BEHAVIOR OF MULTICOMPONENT POLYMERS THROUGH RHEOLOGICAL TESTS 被引量:2
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作者 郑强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第1期1-7,共7页
Rheological measurement has been a preferred approach to the characterization of the structure and phase behaviors for multi-component/multi-phase polymer systems, due to its sensitive response to the changes of struc... Rheological measurement has been a preferred approach to the characterization of the structure and phase behaviors for multi-component/multi-phase polymer systems, due to its sensitive response to the changes of structure for these heterogeneous polymers. In the present article, recent progresses in the studies on rheology for heterogeneous polymer systems including phase-separated polymeric blends and block copolymers are reviewed, mainly depending on the results by the authors' research group. By means of rheological measurements, not only some new fingerprints responsible for the evolution of morphology and structure concerning these polymer systems are obtained, also the corresponding results are significant for design and preparation of novel polymeric structural materials and functional materials. 展开更多
关键词 Heterogeneous polymers Dynamic rheological properties Phase behaviors Morphology and structure.
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MORPHOLOGY AND STRUCTURE OF TRANSFORMATION PRODUCTS FORMED AT INTERMEDIATE TEMPERATURE IN A Cu-Zn-Al ALLOY 被引量:1
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作者 Lu Wei Jiang Bohong Xu Zuyao 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 1992年第2期51-55,共5页
A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The m... A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The morphology and structure of transformation products formed at some intermediate tem peratures isothermally through cooling from high temperature parent phase and up-quenching from DO_(3) parent phase are studied by metallographic.X-ray and electron microscopy analyses.Three regions in the two separate C curves are obtained according to different morphology of precipitate:rod-like a,plate-like bainite and a rods,and bainite plates.Prolonged aging makes bainite plate change gradually into a whose lattice parameters are no different from that of a formed equilibriumly from parent phase.The structure is almost orthorhombic long period structure for bainites formed from B_(2) and DO_(3) parent phase,but monoclinic for martensite from DO_(3).They correspond to the overlapping and separating of(1210)and(2010)diffraction peaks respectively,showing the lower degree of ordering in bainite. 展开更多
关键词 Cu-Zn-Al alloy transformation at intermediate temperature morphology and structure
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Study on urban spatial structure and morphology of Guangzhou-Foshan metropolitan coordinating region compared with Randstad,Netherlands 被引量:1
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作者 Bilin Chen Yimin Sun 《西部人居环境学刊》 2020年第S01期1-9,共9页
In recent years,regional integration of Chinese cities has gradually developed.Meanwhile,metropolitan areas and urban agglomerations have taken shape.On the one hand,the development of the metropolitan area has brough... In recent years,regional integration of Chinese cities has gradually developed.Meanwhile,metropolitan areas and urban agglomerations have taken shape.On the one hand,the development of the metropolitan area has brought about urban spatial expansion,as well as population and economic growth.On the other hand,it has led to problems such as the urban sprawl and suburbanization,increasing pressure on environmental resources,and the decline of urban central areas.Under this background,the Guangdong-Hong Kong-Macao Greater Bay Area Development Plan Outline proposes to accelerate the integration of Guangzhou-Foshan(Guang Fo)Metropolitan Coordinating Region(MCR),and to construct a networked space pattern driven by urban poles and shafts.Based on the academic research of Metropolitan Coordinating Region(MCR),as well as the theory of urban spatial structure and morphology,this study focus on urban spatial patterns and elements in different scales,from two individual cites(Guangzhou and Foshan),Guang Fo MCR,to Guangdong-Hong Kong-Macao(GHM)Greater Bay Area.With GIS and the mapping method,the spatial elements such as green space,water system,built-up area,road network,rail transit network and main pivot points of the Guang Fo MCR are classified,laid out individually and again overlaid in order to figure out the relationship of these elements.At the same time,through the comparative case study of the Randstad MCR in the Netherlands,the enlightenment of solving the development problem of MCR is hopefully to be obtained.As delta cities,the Guang Fo MCR is cut by the multi-channel water network,while the urban built-up area is concentrated in the middle of the MCR and spread out along the traffic corridor to the suburban district.The traffic structure of the Guang Fo MCR is characterized by the outward radiation of the central area of Guangzhou and Foshan.Simultaneously,the traffic connection between Guangzhou and Foshan is relatively weak.Compared with the polycentric spatial structure,which is called Decentralized Compact pattern of Randstad MCR,the Guang Fo MCR presents a city form with little hierarchy but homogeneity,and its urban space is disorderly spread.The bluegreen system of water and vegetation is fragmented because of the urban invasion in Guang Fo MCR,while the green heart in central Randstad is well preserved.As a result,it is well advised to explore a more resilient and ecological urban development in Guang Fo MCR. 展开更多
关键词 GuangFo MCR Spatial structure Urban morphology TRAFFIC Land use Blue-green system
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Morphological Characterization of Brazil Nut Tree (Bertholletia excelsa) Fruit Pericarp
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作者 Gustavo P.Petrechen Marcos Arduin JoséD.Ambrósio 《Journal of Renewable Materials》 SCIE 2019年第7期683-692,共10页
This article presents the overall morphological structure of the Brazil nut tree(Bertholletia excelsa)fruit pericarp,from macro to nano scale.The acquired knowledge would be used for the development of new application... This article presents the overall morphological structure of the Brazil nut tree(Bertholletia excelsa)fruit pericarp,from macro to nano scale.The acquired knowledge would be used for the development of new applications,like using the materials as fillers for biocomposites,or as a hierarchical architecture model for biomimetics.This research was performed using stereo and light microscopy and conventional and force field emission scanning electron microscopy.The pericarp presents three layers:the exocarp,a dark gray,brittle and fragile outer layer;the mesocarp,a beige,dry,rigid,impermeable and fibrous intermediate layer;and the endocarp,an inner layer with similar characteristic as the exocarp,but formed next to the seeds.Morphologically,the exocarp and the endocarp presented minor regions of sclereids,fibers and vascular cell bundles,inside major regions of parenchyma cells.The mesocarp presents a structure of fiber cells regions alternating with sclereids and vascular cells regions,arranged in a composite like arrangement,with the fibers cells bundles acting as randomly oriented disperse phases in a sclereid cells matrix.This arrangement was associated with the mesocarp relative superior proprieties,indicating a great material for using as fillers for biocomposites or in biomimetics applications. 展开更多
关键词 Bertholletia excelsa brazil nut fruit pericarp morphological structure MICROSCOPY
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Morphology and Structure of SiO_2 Film Using Thermal Oxidation Process on(111)Silicon Crystals in Dry Oxygen Atmosphere
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作者 TaokaT. 《Rare Metals》 SCIE EI CAS CSCD 1989年第1期32-38,共7页
By means of scanning electron microscope(SEM)and high voltage electron microscope(HVEM)we have observed and analysed morphology and micro-structure of silicon oxide film with different thickness formed on(111)silicon ... By means of scanning electron microscope(SEM)and high voltage electron microscope(HVEM)we have observed and analysed morphology and micro-structure of silicon oxide film with different thickness formed on(111)silicon monocrystal under dry oxygen atmosphere at 1100℃.Compared with their oxidation kinetic curves consisted of three stages,we suggested a mechanism on forming silicon oxide film.According to electron and X-ray diffraction analyses the silicon oxide films consisted of silica with different crystal structure.We also have discussed a stacking fault and a dislocation formed in the Si-Sio_2 interface region simulaneously forming silicon oxide film. 展开更多
关键词 Silicon Crystals in Dry Oxygen Atmosphere Morphology and structure of SiO2 Film Using Thermal Oxidation Process on SIO
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