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Preparation methods,biological activities,and potential applications of marine algae oligosaccharides:a review 被引量:1
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作者 Lixin Zheng Yang Liu +2 位作者 Shijie Tang Wancong Zhang Kit-Leong Cheong 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期359-370,共12页
Marine algae are valuable sources of health-promoting molecules that have been consumed by Asians for decades.Among aquatic flora,marine algae stand out in terms of high content of marine algae polysaccharides(MAP)suc... Marine algae are valuable sources of health-promoting molecules that have been consumed by Asians for decades.Among aquatic flora,marine algae stand out in terms of high content of marine algae polysaccharides(MAP)such as carrageenan,alginate,fucoidan,laminaran,agarose,rhamnan,and ulvan.When hydrolyzed,MAP generate marine algae oligosaccharides(MAO),which have attracted interest in recent years due to their superior solubility compared with MAP.Besides,MAO have been demonstrated numerous biological activities including antioxidant,antidiabetic,anti-inflammatory,antimicrobial,and prebiotic activities.Thus,this review summarizes the main chemical classes of MAO,their sources,and the main processes used for their production(i.e.,physical,chemical,and biological methods),coupled with a discussion of the advantages and disadvantages of these methods.Highlights of the biological activities of MAO and their potential applications in food,nutraceutical,and pharmaceuticals would also be discussed and summarized. 展开更多
关键词 Marine algae MAO preparation methods Biological activities Potential applications
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Effect of preparation methods on the adsorption property of municipal solid waste-based carbon materials 被引量:1
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作者 宋敏 唐心红 +1 位作者 唐美 卫月星 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期208-214,共7页
Three different preparation methods including steam physical activation, catalytic carbonation and KOH chemical activation methods were used to prepare municipal solid waste- based carbon materials. The methylene blue... Three different preparation methods including steam physical activation, catalytic carbonation and KOH chemical activation methods were used to prepare municipal solid waste- based carbon materials. The methylene blue (MB) adsorption value was applied to evaluate the adsorption capabilities of the prepared carbon materials. The effects of preparation methods on adsorption capability and yield of products were investigated. The yield of carbon materials with the catalytic carbonation method is the highest, and the KOH activation method is the second level. Considering the adsorption performance, the KOH activation method is much more favorable. Among the different components of municipal solid waste-based carbon materials, the adsorption properties of the single component of paperboard, the double components of tire and paperboard, the triple components of tire, paperboard and polyvinyl chloride (PVC), and the multi-component mixtures are better than those of other single-, double-, triple- and multi-component mixtures, respectively. 展开更多
关键词 PYROLYSIS preparation methods WASTE ADSORPTION activated carbon
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Effect of preparation methods on the hydrocracking performance of NiMo/Al_(2)O_(3) catalysts 被引量:4
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作者 Jiake Yang Tongjiu Zuo Jiangyin Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第4期224-230,共7页
In this work,NiMo catalysts with various contents of MoO_(3)were prepared through incipient wetness impregnation by a twostep method(NMxA)and onepot method(NMxB).The catalysts were then characterized by XRD,XPS,NH3TPD... In this work,NiMo catalysts with various contents of MoO_(3)were prepared through incipient wetness impregnation by a twostep method(NMxA)and onepot method(NMxB).The catalysts were then characterized by XRD,XPS,NH3TPD,H_(2)TPR,HRTEM,and N_(2)adsorptiondesorption technologies.The performance of the NiMo/Al_(2)O_(3) catalysts was investigated by hydrocracking lowtemperature coal tar.When the MoO3 content was 15 wt%,the interaction between Ni species and Al_(2)O_(3) on the NM15B catalyst was stronger than that on the NM15A catalyst,resulting in the poor performance of the former.When the MoO^(3) content was 20 wt%,MoO_(3) agglomerated on the surface of the NM20A catalyst,leading to decreased number of active sites and specific surface area and reduced catalytic performance.The increase in the number of MoS_(2) stack layers strengthened the interaction between Ni and Mo species of the NM20B catalyst and consequently improved its catalytic performance.When the MoO_(3) content reached 25 wt%,the active metals agglomerated on the surface of the NiMo catalysts,thereby directly decreasing the number of active sites.In conclusion,the twostep method is suitable for preparing catalysts with large pore diameter and low MoO_(3) content loading,and the onepot method is more appropriate for preparing catalysts with large specific surface area and high MoO_(3) content.Moreover,the NMxA catalysts had larger average pore diameter than the NMxB catalysts and exhibited improved desulfurization performance. 展开更多
关键词 preparation methods Hydrocracking performance The NiMo catalysts MoO_(3)content
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Effect of preparation methods on the structure and catalytic performance of Fe–Zn/K catalysts for CO2 hydrogenation to light olefins 被引量:7
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作者 Xu Wang Jianli Zhang +3 位作者 Jingyu Chen Qingxiang Ma Subing Fan Tiansheng Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第4期761-767,共7页
Potassium promoted iron–zinc catalysts prepared by co-precipitation method(C–Fe–Zn/K),solvothermal method(S–Fe–Zn/K)and hydrothermal method(H–Fe–Zn/K)could selectively convert CO_2to light olefins,respectively.... Potassium promoted iron–zinc catalysts prepared by co-precipitation method(C–Fe–Zn/K),solvothermal method(S–Fe–Zn/K)and hydrothermal method(H–Fe–Zn/K)could selectively convert CO_2to light olefins,respectively.The physicochemical properties of the obtained catalysts were determined by SEM,N_2physisorption,XRD,H_2-TPR,CO_2-TPD and XPS measurements.The results demonstrated that preparation methods had great influences on the morphology,phase structures,reduction and adsorption behavior,and hence the catalytic performance of the catalysts.The samples prepared by hydrothermal and co-precipitation method generated small uniform particles and led to lower specific surface area.In contrast,microspheres with larger specific surface area were formed by self-assembly of nanosheets using solvothermal method.ZnFe_2O_4was the only detectable phase in the fresh C–2Fe–1Zn/K,S–3Fe–1Zn/K and S–2Fe–1Zn/K samples.ZnFe_2O_4and ZnO co-existed with increasing Zncontent in S–1Fe–1Zn/K sample,while ZnO and Fe_2O_3could be observed over H–2Fe–1Zn/K sample.All the used samples contained Fe_3O_4,ZnO and Fe_5C_2.The peak intensity of ZnO was strong in the AR-H–2Fe–1Zn/K sample while it was the lowest in the AR-C–2Fe–1Zn/K sample after reaction.The formation of ZnFe_2O_4increased the interaction between iron and zinc for C–2Fe–1Zn/K and S–Fe–Zn/K samples,causing easier reduction of Fe_2O_3to Fe_3O_4.The surface basicity of the sample prepared by co-precipitation method was much more than that of the other two methods.During CO_2hydrogenation,all the catalysts showed good activity and olefin selectivity.The CO selectivity was increased with increasing Zncontent over S–Fe–Zn/K samples.H–2Fe–1Zn/K catalyst preferred to the production of C_5^+hydrocarbons.CO_2conversion of 54.76%and C_2~=–C_4~=contents of 57.38%were obtained on C–2Fe–1Zn/K sample,respectively. 展开更多
关键词 CO2 hydrogenation Light olefins preparation methods Iron–zinc catalyst
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Effect of preparation methods on Pt/alumina catalysts for the hydrogen iodide catalytic decomposition 被引量:1
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作者 Zhi Chao Wang Lai Jun Wang Ping Zhang Song Zhe Chen Jing Ming Xu Jing Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第1期102-105,共4页
Three kinds of Pt/alumina catalysts were prepared by impregnation-hydrogen reduction, impregnation-hydrazine reduction and electroless plating methods. Their differences in the structures, specific areas and particle ... Three kinds of Pt/alumina catalysts were prepared by impregnation-hydrogen reduction, impregnation-hydrazine reduction and electroless plating methods. Their differences in the structures, specific areas and particle sizes were characterized by XRD, BET and TEM, respectively. Furthermore, their catalytic activities for the hydrogen iodide (HI) decomposition were evaluated in a fixed bed reactor. The results show that the catalyst 5%Pt/Al2O3 prepared by the electroless plating has the optimum catalytic properties for HI decomposition owing to the high dispersion of the platinum nano-particles (〈5 nm) on the alumina supports. 展开更多
关键词 Hydrogen iodide Catalytic decomposition Pt/At2O3 preparation methods
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Influence of preparation methods on the physicochemical properties and catalytic performance of MnO_x-CeO_2 catalysts for NH_3-SCR at low temperature 被引量:45
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作者 Xiaojiang Yao Kaili Ma +4 位作者 Weixin Zou Shenggui He Jibin An Fumo Yang Lin Dong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第1期146-159,共14页
This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature.... This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature. Five different methods, namely, mechanical mixing, impregnation,hydrothermal treatment, co‐precipitation, and a sol‐gel technique, were used to synthesizeMnOx‐CeO2 catalysts. The catalysts were characterized in detail, and an NH3‐SCR model reaction waschosen to evaluate the catalytic performance. The results showed that the preparation methodsaffected the catalytic performance in the order: hydrothermal treatment > sol‐gel > co‐precipitation> impregnation > mechanical mixing. This order correlated with the surface Ce3+ and Mn4+ content,oxygen vacancies and surface adsorbed oxygen species concentration, and the amount of acidic sitesand acidic strength. This trend is related to redox interactions between MnOx and CeO2. The catalystformed by a hydrothermal treatment exhibited excellent physicochemical properties, optimal catalyticperformance, and good H2O resistance in NH3‐SCR reaction. This was attributed to incorporationof Mnn+ into the CeO2 lattice to form a uniform ceria‐based solid solution (containing Mn‐O‐Cestructures). Strengthening of the electronic interactions between MnOx and CeO2, driven by thehigh‐temperature and high‐pressure conditions during the hydrothermal treatment also improved the catalyst characteristics. Thus, the hydrothermal treatment method is an efficient and environment‐friendly route to synthesizing low‐temperature denitrification (deNOx) catalysts. 展开更多
关键词 MnOx‐CeO2 catalyst preparation method Nitrogen oxides Low‐temperature NH3‐SCR Electron interaction Surface acidity
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Influence of preparation methods on CuO-CeO_2 catalysts in the preferential oxidation of CO in excess hydrogen 被引量:6
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作者 Zhigang Liu Renxian Zhou Xiaoming Zheng 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期125-129,共5页
Influence of three different preparation methods, i.e. impregnation, coprecipitation, and inverse coprecipitation, on the preferential oxidation of CO in excess hydrogen (PROX) over CuO-CeO2 catalysts has been inves... Influence of three different preparation methods, i.e. impregnation, coprecipitation, and inverse coprecipitation, on the preferential oxidation of CO in excess hydrogen (PROX) over CuO-CeO2 catalysts has been investigated and CuO-CeO2 catalysts are characterized using BET, XPS, XRD, UV Raman, and TPR techniques. The results show that the catalysts prepared by coprecipitation have smaller particle sizes, well-dispersed CuOx species, more oxygen vacancies, and are more active in the PROX than those prepared by the other methods. However. the inverse coprecipitation depresses the catalytic performance of CuO-CeO2 catalysts and causes the growth of CuO-CeO2 because of different pH value in the precipitation process. 展开更多
关键词 CuO-CeO2 preparation method preferential oxidation CO fuel cell
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Effect of Preparation Methods of Bi_(2)O_(3) Nanoparticles on their Photocatalytic Activity 被引量:5
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作者 DING Peng DU Yao-guo XU Zi-li 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期717-721,共5页
Bi 2O 3 nanoparticles were prepared by means of ammonia precipitation, polyol mediated methods and microemulsion chemical method. The structure and properties of the as-prepared nanoparticles, having been submitted to... Bi 2O 3 nanoparticles were prepared by means of ammonia precipitation, polyol mediated methods and microemulsion chemical method. The structure and properties of the as-prepared nanoparticles, having been submitted to a heat-treatment test at 750 ℃, were characterized by means of XRD, BET, XPS and UV-Vis absorption techniques. The photocatalytic oxidation reactions of benzene, toluene and xylene were used as the model reaction to measure the photocatalytic activity of Bi 2O 3 nanoparticles, respectively. The results show that the crystallite size of Bi 2O 3 prepared with different methods and calcined at 750 ℃ were 50.6, 38.5 and 31.5 nm, respectively. The photocatalytic activity of Bi 2O 3 nanoparticles prepared with the microemulsion chemical method was higher than that of the particles prepared with the polyol mediated method; and that of the particles prepared with the micromulsion chemical method was the highest among the three. The degradation rates of the three pollutants xylene, toluene and benzene decreased in sequence. 展开更多
关键词 Bi_(2)O_(3) preparation method CHARACTERIZATION Photocatalytic activity
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Classification of Preparation Methods and Wearability of Smart Textiles 被引量:1
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作者 FANG Jialu DU Jianxia 《Journal of Donghua University(English Edition)》 CAS 2022年第4期379-391,共13页
In recent years,smart textiles have attracted the attention of scholars from all walks of life,but there is an imbalance between functionality and usability,which affects their marketization process.Firstly,five repre... In recent years,smart textiles have attracted the attention of scholars from all walks of life,but there is an imbalance between functionality and usability,which affects their marketization process.Firstly,five representative smart textiles are introduced and their respective wearability is described around preparation methods.Secondly,it is concluded that the preparation methods of smart textiles can be divided into two categories:fiber methods and finishing methods.The fiber methods refer to making smart fibers into smart textiles.Textiles made by fiber methods are breathable and feel good in the hand,but the mechanical properties are influenced by the production equipment,and the process cost is high.The finishing methods refer to the functional finishing of ordinary textiles.Although the finishing method is simple and convenient,it may reduce the comfort of the textile.Finally,applications and new research in various fields of smart textiles are presented with promising prospects.It is anticipated that this review will serve as a theoretical basis for future research and development of smart textiles.Researchers are expected to create new technologies to overcome the tension between functionality and usability,as well as to increase user comfort and convenience. 展开更多
关键词 smart textiles classification of preparation method WEARABILITY FUNCTIONALITY fabric comfort
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Design,preparation,application of advanced array structured materials and their action mechanism analyses for high performance lithium-sulfur batteries
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作者 Nanping Deng Xiaofan Feng +7 位作者 Yongbing Jin Zhaozhao Peng Yang Feng Ying Tian Yong Liu Lu Gao Weimin Kang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期266-303,I0007,共39页
Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely comme... Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely commercial application and development of LSB is mainly hindered by serious“shuttle effect”of lithium polysulfides(Li PSs),slow reaction kinetics,notorious lithium dendrites,etc.In various structures of LSB materials,array structured materials,possessing the composition of ordered micro units with the same or similar characteristics of each unit,present excellent application potential for various secondary cells due to some merits such as immobilization of active substances,high specific surface area,appropriate pore sizes,easy modification of functional material surface,accommodated huge volume change,enough facilitated transportation for electrons/lithium ions,and special functional groups strongly adsorbing Li PSs.Thus many novel array structured materials are applied to battery for tackling thorny problems mentioned above.In this review,recent progresses and developments on array structured materials applied in LSBs including preparation ways,collaborative structural designs based on array structures,and action mechanism analyses in improving electrochemical performance and safety are summarized.Meanwhile,we also have detailed discussion for array structured materials in LSBs and constructed the structure-function relationships between array structured materials and battery performances.Lastly,some directions and prospects about preparation ways,functional modifications,and practical applications of array structured materials in LSBs are generalized.We hope the review can attract more researchers'attention and bring more studying on array structured materials for other secondary batteries including LSB. 展开更多
关键词 Array structured materials preparation methods and structural designs Action mechanism analyses Advanced Li-S batteries Excellent electrochemical performances and safety
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Edge preparation methods for cutting tools:a review
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作者 Yu ZHOU Wei FANG +6 位作者 Lanying SHAO Yanfei DAI Jiahuan WANG Xu WANG Julong YUAN Weigang GUO Binghai LYU 《Frontiers of Mechanical Engineering》 SCIE CSCD 2023年第4期49-77,共29页
Edge preparation can remove cutting edge defects,such as burrs,chippings,and grinding marks,generated in the grinding process and improve the cutting performance and service life of tools.Various edge preparation meth... Edge preparation can remove cutting edge defects,such as burrs,chippings,and grinding marks,generated in the grinding process and improve the cutting performance and service life of tools.Various edge preparation methods have been proposed for different tool matrix materials,geometries,and application requirements.This study presents a scientific and systematic review of the development of tool edge preparation technology and provides ideas for its future development.First,typical edge characterization methods,which associate the microgeometric characteristics of the cutting edge with cutting performance,are briefly introduced.Then,edge preparation methods for cutting tools,in which materials at the cutting edge area are removed to decrease defects and obtain a suitable microgeometry of the cutting edge for machining,are discussed.New edge preparation methods are explored on the basis of existing processing technologies,and the principles,advantages,and limitations of these methods are systematically summarized and analyzed.Edge preparation methods are classified into two categories:mechanical processing methods and nontraditional processing methods.These methods are compared from the aspects of edge consistency,surface quality,efficiency,processing difficulty,machining cost,and general availability.In this manner,a more intuitive understanding of the characteristics can be gained.Finally,the future development direction of tool edge preparation technology is prospected. 展开更多
关键词 edge preparation method preparation principle cutting edge geometry edge characterization tool performance
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Novel wood-plastic composite fabricated via modified steel slag:Preparation,mechanical and flammability properties
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作者 Ling Zhao Kai Zhao +4 位作者 Zhenwei Shen Yifan Wang Xiaojie Xia Hao Zhang Hongming Long 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2110-2120,共11页
A novel method was developed to enhance the utilization rate of steel slag(SS).Through treatment of SS with phosphoric acid and aminopropyl triethoxysilane(KH550),we obtained modified SS(MSS),which was used to prepare... A novel method was developed to enhance the utilization rate of steel slag(SS).Through treatment of SS with phosphoric acid and aminopropyl triethoxysilane(KH550),we obtained modified SS(MSS),which was used to prepare MSS/wood-plastic composites(MSS/WPCs)by replacing talcum powder(TP).The composites were fabricated through melting blending and hot pressing.Their mechanical and combustion properties,which comprise heat release,smoke release,and thermal stability,were systematically investigated.MSS can improve the mechanical strength of the composites through grafting reactions between wood powder and thermoplastics.Notably,MSS/WPC#50(16wt%MSS)with an MSS-to-TP mass ratio of 1:1 exhibited optimal comprehensive performance.Compared with those of WPC#0 without MSS,the tensile,flexural,and impact strengths of MSS/WPC#50 were increased by 18.5%,12.8%,and 18.0%,respectively.Moreover,the MSS/WPC#50 sample achieved the highest limited oxygen index of 22.5%,the highest vertical burning rating at the V-1 level,and the lowest horizontal burning rate at 44.2 mm/min.The formation of a dense and stable char layer led to improved thermal stability and a considerable reduction in heat and smoke releases of MSS/WPC#50.However,the partial replacement of TP with MSS slightly compromised the mechanical and flame-retardant properties,possibly due to the weak grafting caused by SS powder agglomeration.These findings suggest the suitability of MSS/WPCs for high-value-added applications as decorative panels indoors or outdoors. 展开更多
关键词 modified steel slag wood–plastic composites preparation method mechanical property flame retardant
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Analysis and discussion of different methods of artificial ice-high specimen preparation 被引量:1
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作者 ShuJuan Zhang Wei Ma +1 位作者 ZhiZhong Sun HaiMin Du 《Research in Cold and Arid Regions》 CSCD 2014年第5期440-446,共7页
Because ice-high foundation soil is widely distributed in permafrost regions,the correct preparation of ice-high specimens is of critical interest in engineering design for foundation stability.Past research has shown... Because ice-high foundation soil is widely distributed in permafrost regions,the correct preparation of ice-high specimens is of critical interest in engineering design for foundation stability.Past research has shown that the uniaxial compression strength of ice-high frozen soils changes as the ice or total water content increases; the differences of different methods of specimen preparation are analyzed here and the advantages and disadvantages of them are presented.It is confirmed that the role of crushed ice is significantly different from that of naturally frozen ice in frozen soils,and the size and amount of crushed ice will influence the strength and deformation mechanism of frozen soils.Therefore,it is strongly recommended that when a ice-high specimen is artificially prepared,the ice should be frozen through natural means and not be replaced with crushed ice. 展开更多
关键词 ice-high specimen artificial preparation method STRENGTH DEFORMATION
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Influence of nanosized magnesia on the hydration of borehole-sealing cements prepared using different methods 被引量:1
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作者 Quanle Zou Jinfei Zhan +1 位作者 Xin Wang Zhen Huang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期343-360,共18页
Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas drainage.The expansibilities of cement pastes used in borehole-seali... Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas drainage.The expansibilities of cement pastes used in borehole-sealing processes are critical for the borehole-sealing efect.Nanosized magnesia expansive agents are used to improve the expansibilities of cement pastes and improve the borehole-sealing efect.Nuclear magnetic resonance spectrometry and scanning electron microscopy were adopted to study the efects of nanosized magnesia on the hydration of borehole-sealing cements used with diferent preparation methods.The results showed that an increase in the mass fraction of the nanosized magnesia promoted cement hydration,and the mass fraction was positively correlated with the promotion efect.The use of diferent preparation methods did not change the water-phase distribution in the cement.When using the wet-mixing preparation method,nanosized magnesia promoted the induction,acceleration,and deceleration periods of hydration;when using the dry-mixing preparation method,the nanosized magnesia promoted the induction period of cement hydration,and the promotion efect was less obvious than that seen when using the wet-mixing method.When using the wet-mixing preparation method,the nanosized magnesia was uniformly dispersed,thus enlarging the surface area of the reaction,which provided more nucleation sites for the hydration products of the cement and therefore accelerated the hydration reaction.When using the dry-mixing preparation method,the nanosized magnesia powders were dispersed nonuniformly and aggregated.Under these conditions,only a few nanosized magnesia particles on the surfaces of the aggregated clusters took part in hydration,so only a small number of nucleation sites were provided for the hydration products of cement.This led to inconsistent hydration of cement pastes prepared using the dry-mixing method.The surface porosity of the cement prepared with the wet-mixing preparation method frst decreased and then increased with increases in the mass fraction of the nanosized magnesia.The cement surface exhibited compact hydration products and few pores,and the surface was relatively smooth.In comparison,the surface porosity of the cement prepared using the dry-mixing method fuctuated with increasing mass fraction of the nanosized magnesia,resulting in a rough cement surface and microfractures on some surfaces.The two preparation methods both reduced the surface porosity of the cement.The wet-mixing preparation was more efective and consistent in improving the compactness of the cement than the dry-mixing preparation.These results provide important guidance on the addition of nanosized magnesia in borehole-sealing engineering and the selection of cement preparation methods,and they also lay a solid foundation for realizing safe and efcient gas drainage. 展开更多
关键词 Borehole-sealing cement Nanosized magnesia preparation method HYDRATION Morphological analysis Nuclear magnetic resonance relaxation analysis
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Microstructures and properties of Al_2O_3 dispersion-strengthened copper alloys prepared through different methods 被引量:4
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作者 Zhi-qiao Yan Feng Chen +2 位作者 Fu-xing Ye Dong-ping Zhang Yi-xiang Cai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第12期1437-1443,共7页
Al2O3 dispersion copper alloy powder was prepared by intemal oxidation, and three consolidation methods--high-velocity compaction (HVC), hot pressing (HP), and hot extrusion (HE)--were used to prepare Al2O3 disp... Al2O3 dispersion copper alloy powder was prepared by intemal oxidation, and three consolidation methods--high-velocity compaction (HVC), hot pressing (HP), and hot extrusion (HE)--were used to prepare Al2O3 dispersion-strengthened copper (Cu-Al2O3) alloys. The microstructures and properties of these alloys were investigated and compared. The results show that the alloys prepared by the HP and HE methods exhibited the coarsest and finest grain sizes, respectively. The alloy prepared by the HVC method exhibited the lowest relative density (98.3% vs. 99.5% for HP and 100% for HE), which resulted in the lowest electrical conductivity (81% IACS vs. 86% IACS for HP and 87% IACS for HE). However, this alloy also exhibited the highest hardness (77 HRB vs. 69 HRB for HP and 70 HRB for HE), the highest compressive strength (443 MPa vs. 386 MPa for I/P and 378 MPa for HE), and the best hardness retention among the investigated alloys. The results illustrate that the alloy prepared by the HVC method exhibits high softening temperature and good mechanical properties at high temperatures, which imply long service life when used as spot-welding electrodes. 展开更多
关键词 dispersion-strengthened alloys copper alloys ALUMINA preparation methods microstructure properties
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A review of recent progress in preparation of hollow polymer microspheres 被引量:3
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作者 Wei Bin Wang Shujun +3 位作者 Song Hongguang Liu Hongyan Li Jie Liu Ning 《Petroleum Science》 SCIE CAS CSCD 2009年第3期306-312,共7页
The preparation methods of hollow polymer microspheres both at home and abroad are summarized, and their preparation mechanisms and developmental states are presented. These methods include the liquid droplet method, ... The preparation methods of hollow polymer microspheres both at home and abroad are summarized, and their preparation mechanisms and developmental states are presented. These methods include the liquid droplet method, dried-gel droplet method, self-assembly method, microencapsulation method, emulsion polymerization method and the template method. Hollow polystyrene microspheres are the most extensively studied in the research of hollow polymer microspheres. Through comparison of the advantages and disadvantages of different preparation methods, it is concluded that microencapsulation method is most suitable for preparing polystyrene hollow microspheres. 展开更多
关键词 preparation methods hollow polymer microspheres preparation mechanism polystyrene hollow microspheres microencapsulation method
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Recent Progress in Preparation and Application of Nano-Chitin Materials 被引量:5
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作者 Xuefei Yang Jie Liu +2 位作者 Ying Pei Xuejing Zheng Keyong Tang 《Energy & Environmental Materials》 SCIE 2020年第4期492-515,共24页
Chitin is a kind of natural macromolecule material which was first discovered in mushrooms and was widely found in the shells of crustaceans and arthropods,the cell walls of fungi(yeast and mold)and algae,and the moll... Chitin is a kind of natural macromolecule material which was first discovered in mushrooms and was widely found in the shells of crustaceans and arthropods,the cell walls of fungi(yeast and mold)and algae,and the mollusks.The original chitin in nature usually has an antiparallel molecular chain alignment forming nanofibers connected by inter-and intramolecular hydrogen bonds.These microfibers consist of nanofibers about 2-5 nm in diameter,and about 300 nm long,embedded by protein matrices.Due to their unique dimensional,optical,mechanical,and other characteristics,the preparation of nano-chitin materials is an important subject.It is possible to extract nano-chitins from their sources with various methods,including acid hydrolysis,mechanical disintegration,TEMPO-mediated oxidation,electrospinning,and others.In this article,the latest progress in recent years in the preparation and applications of nano-chitin were reviewed.The morphology of the nano-chitins obtained from the above methods was presented.The advantages and disadvantages of each method were analyzed.An overview of applications of nano-chitins was discussed,including biomedicine,food applications,water treatment,green electronic materials,enzyme immobilization carriers,cotton textile materials,cosmetics,and others. 展开更多
关键词 APPLICATIONS nano-chitin preparation methods STRUCTURE
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Difference among the quality indices,chemical composition and frying performance of galangal flavored sunflower oil prepared by three methods 被引量:1
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作者 Haoduo Yang Yingying Wang +1 位作者 Dongying Wang Xuede Wang 《Grain & Oil Science and Technology》 2022年第2期70-78,共9页
Flavored vegetable oils have attracted more and more attentions from consumers and researchers due to their high oxidative stability and sensory quality.In the present study,the quality indices,chemical composition an... Flavored vegetable oils have attracted more and more attentions from consumers and researchers due to their high oxidative stability and sensory quality.In the present study,the quality indices,chemical composition and frying performance of galangal flavored sunflower oil prepared by infusion method(GFSO-I),combination pressing method(GFSO-C)and direct addition method(GFSO-A)were investigated.The results displayed that the preparation time,the levels for the acid value(AV),peroxide value(PV),p-anisidine value(AnV),total oxidation value(TOTOX),and the values for total polar compounds(TPC),thiobarbituric acid(TBA),K232 and K268 of GFSO-C were prominently low(P<0.05),compared with that of GFSO-I and GFSO-A,while the fatty acid composition of them were similar.In the frying of Chinese Maye(tradional Chinese food,fried dough stick)at 180°C for 30 h,the values for TPC,TBA,K232 and K268,polymer,viscosity and b*of GFSO-C were obviously low(P<0.05),while the value for L*was obviously high(P<0.05),compared with that of GFSO-I and GFSO-A.In the sensory evaluation,the flavor,taste,crispness and overall acceptance of Chinese Maye fried by GFSO-C were better than that of Chinese Maye fried by GFSO-I and GFSO-A.Consequently,GFSO-C is more suitable for cooking,and the combination pressing method is optimal for industrial production of GFSO. 展开更多
关键词 Galangal Sunflower oil Flavored oil Quality indices Frying performance preparation methods
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Study on the preparation of Pt nanocapsules
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作者 Yi-fan Zhang Zhen Ji +3 位作者 Ke Chen Bo-wen Liu Cheng-chang Jia Shan-wu Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第1期109-114,共6页
Ag@Pt core-shell nanoparticles(Ag@Pt NPs) were prepared by a co-reduction method. Pt nanocapsules with diameters of less than 10 nm were obtained by an electrochemical method. Cyclic voltammetry(CV) scanning was u... Ag@Pt core-shell nanoparticles(Ag@Pt NPs) were prepared by a co-reduction method. Pt nanocapsules with diameters of less than 10 nm were obtained by an electrochemical method. Cyclic voltammetry(CV) scanning was used to cavitate the Ag@Pt NPs, and the morphology, structure, and cavitation conditions were studied. The results indicate that the effective cavitation conditions to obtain Pt nanoparticles from Ag@Pt NPs are a scanning voltage of 0 to 0.8 V and continuous CV scanning over 2 h. This cavitation method is also applicable for the syntheses of Ir, Ru, and Ru-Pt nanocapsules. 展开更多
关键词 PLATINUM NANOCAPSULES CAVITATION preparation methods
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Research Progress of High Entropy Ceramic Materials
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作者 Song WU Shikai LIU +5 位作者 Jialin WANG Bibo HAN Shaoyi SHEN Zhigang YU Zhaobo ZHANG Xinhua ZHENG 《Research and Application of Materials Science》 2024年第1期16-22,共7页
High-entropy materials(HEMs)have better mechanical,thermal,and electrical properties than traditional materials due to their special"high entropy effect".They can also adjust the performance of high entropy ... High-entropy materials(HEMs)have better mechanical,thermal,and electrical properties than traditional materials due to their special"high entropy effect".They can also adjust the performance of high entropy ceramics by adjusting the proportion of raw materials,and have broad application prospects in many fields.This article provides a review of the high entropy effect,preparation methods,and main applications of high entropy ceramic materials,especially exploring relevant research on high entropy perovskite ceramics.It is expected to provide reference for the promotion of scientific research and the development of further large-scale applications of high-entropy ceramic materials. 展开更多
关键词 High-entropy ceramic materials high entropy effect preparation method perovskite structure research prog
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