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Morphology Control of Anatase TiO2 by Surfactant-assisted Hydrothermal Method 被引量:10
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作者 王富民 石战胜 +2 位作者 巩峰 酒金亭 ADACHI Motonari 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期754-759,共6页
By hydrolysing titanium isopropoxide in a long hydrocarbon chain surfactant-containing solution, TiO2 fine particles with a diversity of well-defined morphologies was synthesized in this study by a hydrothermal route.... By hydrolysing titanium isopropoxide in a long hydrocarbon chain surfactant-containing solution, TiO2 fine particles with a diversity of well-defined morphologies was synthesized in this study by a hydrothermal route. The structural change during the formation process was monitored by scanning electron microscopy, transmission electron microscopy and X-ray diffraction analysis. TiO2 with various morphologies such as particle, sheet, rod, tube and flower-like shape was obtained by carefully controlling the preparation conditions. The experimental results show that the pH value is crucial for shape control of the produced TiO2 because it can change the charge state of the surfactant in the solution and the adsorption potential of the surfactant on the TiO2 surface. The shape evolvement of anatase TiO2 was elucidated by quenching the reaction at different stage and the formation mechanism of different shaped TiO2 was suggested. 展开更多
关键词 morphology control titanium dioxide charged state ANATASE
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Morphology Control of SrCO_3 Crystals using Complexons as Modifiers in the Ethanol-water mixtures 被引量:3
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作者 张明轩 霍冀川 +2 位作者 于永生 崔彩萍 雷永林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1223-1229,共7页
Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlappin... Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlapping plate-like, hexagonal star-like, dumbbell-like, etc. can be synthesized in the ethanol-water mixtures. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrograph (FT-IR). The interrelated effect mechanism is presented in the end. Results show that the modifier carboxyl groups play a significant role in controlling the SrCO3 crystal morphologies, which can alter the crystal growth unit (Sr^2+) supply mode and induce the crystal formation with the morphologies matching their spatial configurations. 展开更多
关键词 SrCO3 complexon MODIFIER morphology control ethanol-water mixtures
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Efficient and stable planar all-inorganic perovskite solar cells based on high-quality CsPbBr3 films with controllable morphology 被引量:7
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作者 Xiaojing Wan Ze Yu +6 位作者 Wenming Tian Fuzhi Huang Shengye Jin Xichuan Yang Yi-Bing Cheng Anders Hagfeldt Licheng Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第7期8-15,I0001,共9页
All-inorganic cesium lead bromide(CsPbBr3)perovskite is attracting growing interest as functional materials in photovoltaics and other optoelectronic devices due to its superb stability.However,the fabrication of high... All-inorganic cesium lead bromide(CsPbBr3)perovskite is attracting growing interest as functional materials in photovoltaics and other optoelectronic devices due to its superb stability.However,the fabrication of high-quality CsPbBr3 films still remains a big challenge by solution-process because of the low solubility of the cesium precursor in common solvents.Herein,we report a facile solution-processed approach to prepare high-quality CsPbBr3 perovskite films via a two-step spin-coating method,in which the Cs Br methanol/H2 O mixed solvent solution is spin-coated onto the lead bromide films,followed by an isopropanol-assisted post-treatment to regulate the crystallization process and to control the film morphology.In this fashion,dense and uniform CsPbBr3 films are obtained consisting of large crystalline domains with sizes up to microns and low defect density.The effectiveness of the resulting CsPbBr3 films is further examined in perovskite solar cells(PSCs)with a simplified planar architecture of fluorine–doped tin oxide/compact Ti O2/CsPbBr3/carbon,which deliver a maximum power conversion efficiency of 8.11%together with excellent thermal and humidity stability.The present work offers a simple and effective strategy in fabrication of high-quality CsPbBr3 films for efficient and stable PSCs as well as other optoelectronic devices. 展开更多
关键词 All-inorganic perovskite solar cells CsPbBr3 morphology control Solution-processed Stability
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Morphology control of ultrafine cuprous oxide powder and its growth mechanism 被引量:2
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作者 曹艳 王岳俊 +1 位作者 周康根 毕贞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第S1期216-220,共5页
Four shapes of Cu2O particles as sphere,cube,truncated octahedron and octahedron were prepared via glucose reduction of Cu(Ⅱ)under alkaline condition.The products were characterized by XRD and SEM.The effects of the ... Four shapes of Cu2O particles as sphere,cube,truncated octahedron and octahedron were prepared via glucose reduction of Cu(Ⅱ)under alkaline condition.The products were characterized by XRD and SEM.The effects of the precursor(CuO,Cu(OH)2), reaction temperature and glucose concentration on morphology of Cu2O particles were investigated,and the mechanism of morphology control was discussed on the basic theory of crystal nucleation and growth.It is found that the Cu+supersaturation is remarkably influenced by the precursor kind,reaction temperature and glucose concentration,and the morphology of Cu2O particles can be controlled by the Cu+supersaturation. 展开更多
关键词 cuprous oxide morphology control SUPERSATURATION growth mechanism
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Theory and Practice of Oxide Inclusion Composition and Morphology Control in Spring Steel Production 被引量:5
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作者 XUEZheng-liang LIZheng-bang +3 位作者 ZHANGJia-wen YANGWu GANChao-fu WANGYu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第2期38-44,共7页
In order to control the composition,morphology and size distribution of oxide inclusions in spring steel,the relationship between the content or activity of aluminum and calcium in molten steel and compositions of oxi... In order to control the composition,morphology and size distribution of oxide inclusions in spring steel,the relationship between the content or activity of aluminum and calcium in molten steel and compositions of oxide inclusion precipitated at different temperatures was determined based on thermodynamic equilibrium for spring steel 60Si2 MnA,and has been verified by practice.The size distribution of non-metallic inclusions electrolytically extracted from specimens of hot rolled spring steel was determined by image analyzer.The results show that there are a great deal of large inclusions in spring steel produced by the conventional process,and the quantity and the size of large inclusions in spring steel produced by new process are largely reduced.As a result,the fatigue properties of the spring steel produced by new process are highly improved,and the ratio ofσ-1/σbis raised from 0.451 to 0.468. 展开更多
关键词 spring steel oxide inclusion inclusion composition control inclusion morpholo-gy control fatigue limit strength
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Alginate-based complex fibers with the Janus morphology for controlled release of co-delivered drugs 被引量:2
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作者 Wing-Fu Lai Eric Huang Kwok-Ho Lui 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2021年第1期77-85,共9页
Hydrogels are soft materials consisting of a three-dimensional network of polymer chains.Over the years,hydrogels with different compositions have been developed as drug carriers for diverse biomedical applications,ra... Hydrogels are soft materials consisting of a three-dimensional network of polymer chains.Over the years,hydrogels with different compositions have been developed as drug carriers for diverse biomedical applications,ranging from cancer therapy and wound care to the treatment of neurodegenerative and inflammatory diseases.Most of these carriers,however,are designed only to deliver single agents.Carriers based on hydrogels for co-delivery of multiple agents,with the release rate of each of the co-delivered agents tunable,are lacking.This study reports a one-pot method of fabricating alginate-based complex fibers with the Janus morphology,with carboxymethyl cellulose sodium functioning as a polymeric modifier of the properties of each of the fiber compartments.By using malachite green and minocycline hydrochloride as model drugs,the generated fibers demonstrate the capacity of enabling the release profile of each of the co-delivered drugs to be precisely controlled.Along with their negligible toxicity and the retention of the activity of the loaded drugs,the complex fibers reported in this study warrant further development and optimization for applications that involve co-delivery of multiple agents. 展开更多
关键词 Janus morphology Complex fiber Tunable release profiles CO-DELIVERY controlled release
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Morphology control of aluminum nitride(AlN)for a novel high-temperature hydrogen sensor 被引量:1
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作者 Angga Hermawan Yusuke Asakura Shu Yin 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第11期1560-1567,共8页
Hydrogen is a promising renewable energy source for fossil-free transportation and electrical energy generation.However,leaking hydrogen in high-temperature production processes can cause an explosion,which endangers ... Hydrogen is a promising renewable energy source for fossil-free transportation and electrical energy generation.However,leaking hydrogen in high-temperature production processes can cause an explosion,which endangers production workers and surrounding areas.To detect leaks early,we used a sensor material based on a wide bandgap aluminum nitride(AlN)that can withstand a high-temperature environment.Three unique AlN morphologies(rod-like,nest-like,and hexagonal plate-like)were synthesized by a direct nitridation method at 1400℃usingγ-AlOOH as a precursor.The gas-sensing performance shows that a hexagonal plate-like morphology exhibited p-type sensing behavior and showed good repeatability as well as the highest response(S=58.7)toward a 750 ppm leak of H2 gas at high temperature(500°C)compared with the rod-like and nest-like morphologies.Furthermore,the hexagonal plate-like morphology showed fast response and recovery times of 40 and 82 s,respectively.The surface facet of the hexagonal morphology of AlN might be energetically favorable for gas adsorption–desorption for enhanced hydrogen detection. 展开更多
关键词 aluminum nitride controllable morphology direct nitridation γ-AlOOH hydrogen sensor
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Morphology-Controlled Growth of A1N One-Dimensional Nanostructures 被引量:1
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作者 Ting XIE Min YE +5 位作者 Xiaosheng FANG Zhi JIANG Li CHEN Mingguang KONG Yucheng WU Lide ZHANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第4期608-614,共7页
Aluminum nitride (AIN) nanowires, serrated nanoribbons, and nanoribbons were selectively obtained through a simple chloride assisted chemical vapor deposition process. The morphologies of the products could be contr... Aluminum nitride (AIN) nanowires, serrated nanoribbons, and nanoribbons were selectively obtained through a simple chloride assisted chemical vapor deposition process. The morphologies of the products could be controlled by adjusting the deposition position and the flux of the reactant gas. The morphologies and structures of the AIN products were investigated in detail. The formation mechanism of the as-prepared different morphologies of AIN one-dimensional (ID) nanostructures was discussed on the basis of the experimental results. 展开更多
关键词 Aluminum nitride morphology-controlled growth One-dimensional nanostructure
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Morphology-controlled synthesis of SrTiO_3 micro-scale particles
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作者 曹加锋 冀月霞 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期520-527,共8页
A novel and simple strategy of morphology-controlled Sr Ti O3(ST) micro-scale particle synthesis by the flux method is reported. Systematic experiments are designed to realize the tunable morphologies of the particl... A novel and simple strategy of morphology-controlled Sr Ti O3(ST) micro-scale particle synthesis by the flux method is reported. Systematic experiments are designed to realize the tunable morphologies of the particles when the flux salt,sintering process, and the precursors are changed. The ST plates can be synthesized by plate-like Bi4Ti3O12(BIT) precursors in Na Cl flux. However, the as-synthesized Bi4Ti3O12 grains transform into reticular particles and finally into rods at higher temperature in Na Cl and KCl compounds. Besides, cubic ST particles are also prepared using different precursors as a comparative experiment. This study provides a strategy for further investigations in designing the morphology-controlled particles and efficient anisotropic materials of perovskite structure such as ferroelectric and photocatalyst. 展开更多
关键词 morphology-controlled synthesis Sr Ti O3 particles topochemical microcrystal conversion
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Morphology and controlling factors of the longitudinal profile of gullies in the Yuanmou dry-hot valley 被引量:3
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作者 DING Lin QIN Fa-chao +6 位作者 FANG Hai-dong LIU Hui ZHANG Bin SHU Cheng-qiang DENG Qing-chun LIU Gang-cai YANG Qian-qian 《Journal of Mountain Science》 SCIE CSCD 2017年第4期674-693,共20页
The morphology of the gully longitudinal profile (GLP) is an important topographic index of the gully bottom associated with the evolution of the gullies. This index can be used to predict the development trend and ... The morphology of the gully longitudinal profile (GLP) is an important topographic index of the gully bottom associated with the evolution of the gullies. This index can be used to predict the development trend and evaluate the eroded volumes and soil losses by gullying. To depict the morphology of GLP and understand its controlling factors, the Global Positioning System Real-time Kinematic (GPS RTK) and the total station were used to measure the detail points along the gully bottom of 122 gullies at six sites of the Yuanmou dry-hot Valley. Then, nine parameters including length (Lt), horizontal distance (Dh), height (H), vertical erosional area (A), vertical curvature (Co), concavity (Ca), average gradient (Ga), gully length-gradient index (GL), normalized gully length-gradient index (Ngl), were calculated and mapped using CASS, Excel and SPSS. The results showed that this study area is dominated by slightly concave and medium gradient GLPs, and the lithology of most gullies is sandstone and siltstone. Although different types of GLPs appear at different sites, all parameters present a positively skewed distribution. There are relatively strong correlations between several parameters: namely Lt and H, Dh and H, Lt and A, Dh and A, H and GL. Most GLPs, except three, have a best fit of exponential functions with quasi- straight shapes. Soil properties, vegetation coverage, piping erosion and topography are important factors to affect the GLP morphology. This study provides useful insight into the knowledge of GLP morphology and its influential factors that are of critical importance to prevent and control gully erosion. 展开更多
关键词 Gully longitudinal profile Morphological characteristics Soil erosion Gully erosion controlling factors Dry-hot valley
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Planar morphology and controlling factors of the gullies in the Yuanmou Dry-hot Valley based on field investigation 被引量:3
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作者 DENG Qingchun MIAO Fang +5 位作者 ZHANG Bin LUO Mingliang LIU Hui LIU Xiaojiao QIN Fachao LIU Gangcai 《Journal of Arid Land》 SCIE CSCD 2015年第6期778-793,共16页
The plane form of a gully can provide a basis for evaluating the gully volume and erosion rate, acting process, and evolutionary stage. For describing the planar characteristics of a permanent gully and understanding ... The plane form of a gully can provide a basis for evaluating the gully volume and erosion rate, acting process, and evolutionary stage. For describing the planar characteristics of a permanent gully and understanding their controlling factors, this study, utilizing a total station and GPS RTK, measured the shoulder lines and channel curves of 112 gullies in six sites of the Yuanmou Dry-hot Valley and then mapped them by Arc GIS software and calculated nine parameters. The results showed that the channel lengths range from 10.88 to 249.11 m; the widths range from 6.20 to 40.99 m; the perimeters range from 54.11 to 541.67 m; the gully areas range from 153.02 to 6,930.30 m2; the left-side areas range from 92.93 to 4,027.20 m2; and the right-side areas range from 63.65 to 3,539.77 m2. The slightly sinuous and straight gullies account for 73.21% of the total gullies; the quantity of the right skewed gullies is 8.93% greater than that of the left skewed ones based on the symmetry ratio; the shape ratios range from 1.12 to 1.40 and the morphology ratios from 0.038 to 1.294; the fractal dimension is 1.192. Gullies in different sites have diverse planar characteristics. Except for the symmetry index, which was close to a negatively skewed distribution, all of the other parameters had the characteristic of positively skewed distribution. The gully area is related to the length and width, but the gully length has a weak correlation with the width. The evolutionary stage, topographic conditions, strata, soil properties, and piping erosion played very important roles in the gully planar morphology. This study could provide useful information for controlling gully erosion and safeguarding human habitation and engineering buildings. 展开更多
关键词 gully plane form morphological parameters controlling factors Yuanmou Dry-hot Valley
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License Plate Recognition for Parking Control System by Mathematical Morphology 被引量:1
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作者 Javier Ortiz Alberto Gómez 《Journal of Electronic Science and Technology》 CAS 2014年第1期81-84,共4页
Nowadays, license plate recognition for parking systems is a critical task to provide automatic control of customers and payment. This paper introduces a new method for automatic recognition of license plates of vehic... Nowadays, license plate recognition for parking systems is a critical task to provide automatic control of customers and payment. This paper introduces a new method for automatic recognition of license plates of vehicles by mathematical morphology. The proposed method can provide the license plate number of the plates in different light conditions, colors, sizes, and inclination (angles). The algorithm can recognize the license plates of European Union vehicles quickly and correctly. The pattern learning of mathematical skeletons has high efficiency in the process. The performance of the algorithm is demonstrated well by the test in a parking control system. 展开更多
关键词 License plate recognition mathe-matical morphology skeleton.
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Study of brain morphology change in Alzheimer’s disease and amnestic mild cognitive impairment compared with normal controls 被引量:4
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作者 Huanqing Yang Hua Xu +10 位作者 Qingfeng Li Yan Jin Weixiong Jiang Jinghua Wang Yina Wu Wei Li Cece Yang Xia Li Shifu Xiao Feng Shi Tao Wang 《General Psychiatry》 CSCD 2019年第2期75-83,共9页
Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer&#... Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer's disease. How to distinguish diseases in the early stage for the purposes of early diagnosis and treatment is an important topic. Aims The purpose of our study was to investigate the differences in brain cortical thickness and surface area among elderly patients with AD, elderly patients with amnestic MCI (aMCI) and normal controls (NC). Methods 20 AD patients, 21 aMCIs and 25 NC were recruited in the study. FreeSurfer software was used to calculate cortical thickness and surface area among groups. Results The patients with AD had less cortical thickness both in the left and right hemisphere in 17 of the 36 brain regions examined than the patients with aMCI or NC. The patients with AD also had smaller cerebral surface area both in the left and right hemisphere in 3 of the 36 brain regions examined than the patients with aMCI or NC. Compared with the NC, the patients with aMCI only had slight atrophy in the inferior parietal lobe of the left hemisphere, and no significant difference was found. Conclusion AD, as well as aMCI (to a lesser extent), is associated with reduced cortical thickness and surface area in a few brain regions associated with cognitive impairment. These results suggest that cortical thickness and surface area could be used for early detection of AD. 展开更多
关键词 brain morphology CHANGE amnestic MILD COGNITIVE IMPAIRMENT compared aMCI NC
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Quaternary tectonic control on channel morphology over sedimentary low land:A case study in the Ajay-Damodar interfluve of Eastern India 被引量:3
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作者 Suvendu Roy Abhay Sankar Sahu 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第6期927-946,共20页
The style of active tectonic on the deformation and characterization of fluvial landscape has been investigated on three typical skrike-slip fault zones of the Ajay-Damodar Interfluve(ADI) in Eastern India through f... The style of active tectonic on the deformation and characterization of fluvial landscape has been investigated on three typical skrike-slip fault zones of the Ajay-Damodar Interfluve(ADI) in Eastern India through field mapping,structural analysis and examination of digital topography(ASTER-30 m),multispectral imageries,and Google Earth images,Channel morphology in Quaternary sediment is more deformed than Cenozoic lateritic tract and igneous rock system by the neotectonic activities,The structural and lithological controls on the river system in ADI region are reflected by distinct drainage patterns,abrupt change in flow direction,offset river channels,straight river lines,ponded river channel,marshy lands,sag ponds,palaeo-channels,alluvial fans,meander cutoffs,multi-terrace river valley,incised compressed meander,convexity of channel bed slope and knick points in longitudinal profile,Seven morphotectonic indices have been used to infer the role of neotectonic on the modification of channel morphology,A tectonic index map for the ADI region has been prepared by the integration of used morphotectonic indices,which is also calibrated by Bouguer gravity anomaly data and field investigation. 展开更多
关键词 Active tectonic Skrike-slip fault Channel morphology Morphotectonic indices Neotectonic map
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Band Engineering and Morphology Control of Oxygen‑Incorporated Graphitic Carbon Nitride Porous Nanosheets for Highly Efficient Photocatalytic Hydrogen Evolution 被引量:6
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作者 Yunyan Wu Pan Xiong +7 位作者 Jianchun Wu Zengliang Huang Jingwen Sun Qinqin Liu Xiaonong Cheng Juan Yang Junwu Zhu Yazhou Zhou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第3期95-106,共12页
Graphitic carbon nitride(g-C3N4)-based photocatalysts have shown great potential in the splitting of water.However,the intrinsic drawbacks of g-C3N4,such as low surface area,poor diffusion,and charge separation effici... Graphitic carbon nitride(g-C3N4)-based photocatalysts have shown great potential in the splitting of water.However,the intrinsic drawbacks of g-C3N4,such as low surface area,poor diffusion,and charge separation efficiency,remain as the bottleneck to achieve highly efficient hydrogen evolution.Here,a hollow oxygen-incorporated g-C3N4 nanosheet(OCN)with an improved surface area of 148.5 m2 g^−1 is fabricated by the multiple thermal treatments under the N2/O2 atmosphere,wherein the C–O bonds are formed through two ways of physical adsorption and doping.The physical characterization and theoretical calculation indicate that the O-adsorption can promote the generation of defects,leading to the formation of hollow morphology,while the O-doping results in reduced band gap of g-C3N4.The optimized OCN shows an excellent photocatalytic hydrogen evolution activity of 3519.6μmol g^−1 h^−1 for~20 h,which is over four times higher than that of g-C3N4(850.1μmol g^−1 h^−1)and outperforms most of the reported g-C3N4 catalysts. 展开更多
关键词 Graphitic carbon nitride nanosheet Hollow morphology Oxygen incorporating Multiple thermal treatment Photocatalytic hydrogen evolution
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Preparation of ultrafine silver powders with controllable size and morphology 被引量:9
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作者 Qing-hua TIAN Duo DENG +1 位作者 Yu LI Xue-yi GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第3期524-533,共10页
The ultrafine silver powders were prepared by liquid reduction method using Arabic gum as dispersant.The effects of different dispersants,pH values,and temperature on the morphology and particle size of silver powders... The ultrafine silver powders were prepared by liquid reduction method using Arabic gum as dispersant.The effects of different dispersants,pH values,and temperature on the morphology and particle size of silver powders were investigated.It is found that Arabic gum can better adsorb on silver particles via chemical adsorption,and it shows the best dispersive effect among all the selected dispersants.The particle size of silver powders can be finely tuned from 0.34 to 4.09μm by adjusting pH values,while the morphology of silver powders can be tuned by changing the temperature.The silver powders with high tap density higher than 4.0 g/cm3 were successfully prepared in a wide temperature range of 21.8-70°C.Especially,the tap density is higher than 5.0 g/cm3 when the temperature is optimized to be 50°C.The facile process and high silver concentration of this method make it a promising way to prepare high quality silver powders for electronic paste. 展开更多
关键词 ultrafine silver powder Arabic gum dispersion mechanism tap density controllable preparation
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Morphology, Size-controlled Synthesis of CoO Nanostructure and Its Magnetic Property 被引量:1
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作者 贾潇 岳芳 +2 位作者 杨光 潘海波 刘文革 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第10期1472-1478,共7页
CoO nanostructures with tunable morphology and size have been prepared via a simple one-pot solvothermal synthesis. The as-prepared nanoparticles were fully characterized using X-ray diffraction(XRD), transmission e... CoO nanostructures with tunable morphology and size have been prepared via a simple one-pot solvothermal synthesis. The as-prepared nanoparticles were fully characterized using X-ray diffraction(XRD), transmission electron microscopy(TEM), field-emission scanning electron microscope(FESEM), etc. The morphology and size of the product can be easily controlled by adjusting the raw materials added. Reaction time and the solvent ratio also play important roles in the synthesis of octahedral nanostructures. The magnetic property of the as-prepared samples was also investigated. 展开更多
关键词 controlled synthesis CoO nanostructure magnetic property
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Control of Crystal Size and Morphology of Calcium Carbonate Crystal Polymorphism 被引量:1
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作者 Wakana Nagaki Norihito Doki +3 位作者 Masaaki Yokota Kazuo Yamashita Toshiji Kojima Toshiyuki Tanaka 《Journal of Materials Science and Chemical Engineering》 2021年第4期38-45,共8页
Calcium carbonate, the main component of lime, has been widely used in industry due to its stability and economy. Calcium carbonate has three types of crystalline polymorphism, calcite, aragonite and vaterite, each wi... Calcium carbonate, the main component of lime, has been widely used in industry due to its stability and economy. Calcium carbonate has three types of crystalline polymorphism, calcite, aragonite and vaterite, each with different properties. Therefore, the control of crystal polymorphism is required for industrial applications. In addition, the control of crystal size and shape is similarly required for different applications. In this study, the effect of SrCO<sub>3</sub> on the size control of fine aragonite-type calcium carbonate crystals by uniform urea precipitation and the effect of SrCO<sub>3</sub> addition was investigated by adding solid strontium carbonate and dissolved strontium carbonate. The addition of solid strontium carbonate affected the crystal polymorphism and size of the calcium carbonate produced, depending on the properties of the solid particles and the amount of SrCO<sub>3</sub> added. Experiments on the addition of dissolved SrCO<sub>3</sub> showed that the supersaturation formation rate could be controlled to control the crystal polymorphism. 展开更多
关键词 CaCO3 ARAGONITE SrCO3 Crystal Polymorphism Size control
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Template-free synthesis of morphology- and size-controlled nano indium hydroxide
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作者 Chang-Yu Li Shou-xin Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第12期1154-1161,共8页
Morphology-and size-controlled In(OH)3 nanocrystals were synthesized via a novel, low-cost and low-temperature (70°C) route in the absence of any template and surfactant. The as-prepared products were charact... Morphology-and size-controlled In(OH)3 nanocrystals were synthesized via a novel, low-cost and low-temperature (70°C) route in the absence of any template and surfactant. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) with selected area electron diffraction (SAED). The morphology and size of In(OH)3 nanostructures can be controlled by adjusting the reaction conditions such as the reaction time, the concen-tration of the alkali, and the alkaline source. A possible mechanism for the evolution of the morphology- and size-controlled In(OH)3 was proposed. In addition, the optical properties of the In(OH)3 prepared by this method were studied by diffuse reflection spectra (DRS) and photoluminescence (PL) spectroscopy, and the results exhibit an obvious change of adsorption edges. The thermal behaviors of the as-prepared products were also explored by thermo-gravimetric (TG) and differential scanning calorimetry (DSC) measurements. According to the results of TG-DSC, the pure phase and uniformity of the In2O3 nanocube and nanorod can be obtained by annealing In(OH)3 precur-sors directly at 300°C. 展开更多
关键词 indium hydroxide synthesis NANOCRYSTALS nanostructures morphology optical properties
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Identification of Quantitative Trait Loci Controlling Floral Morphology of Rice Using a Backcross Population between Common Cultivated Rice, <i>Oryza sativa</i>and Asian Wild Rice, <i>O. rufipogon</i>
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作者 Ryo Ishikawa Takafumi Watabe +2 位作者 Ryo Nishioka Pham Thien Thanh Takashige Ishii 《American Journal of Plant Sciences》 2017年第4期734-744,共11页
Differences in floral morphologies affect pollination behaviour in many flowering plants. In the genus Oryza, several differences in the size of floral organs are known. In this study, we focused on the differences in... Differences in floral morphologies affect pollination behaviour in many flowering plants. In the genus Oryza, several differences in the size of floral organs are known. In this study, we focused on the differences in the size of floral organs between common cultivated rice, Oryza sativa L. and its wild ancestor, O. rufipogon. We compared floral morphologies between cultivated rice O. sativa cv. Nipponbare and O. rufipogon W630. We first evaluated temporal changes in filament and anther lengths. W630 had longer filaments with rapid elongation within 15 min after spikelet opening. W630 also had longer anthers than Nipponbare, and size of anther was consistent throughout all time examined. We also analysed other six floral traits, and found that W630 had higher stigma and style length, as well as lemma and palea length, but lower lemma and palea width. Quantitative trait locus (QTL) analysis was performed to identify the loci controlling these floral traits, using backcross recombinant inbred lines derived from a cross between Nipponbare and W630. A total of 11 significant QTLs were identified. Of these, two pairs of QTLs for lemma and palea length and one pair for lemma and palea width overlapped, suggesting that common genetic factors may be the reason for the differences in these traits. In addition, we performed QTL analysis for grain size, and found that QTLs for grain size coincided with those for lemma and palea size, indicating that grain size is partly controlled by glume capacity. The QTLs identified in this study will be informative for understanding genetic changes associated with rice domestication. 展开更多
关键词 RICE Oryza sativa O. RUFIPOGON FLORAL morphology Domestication
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