A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfo...A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfone)(PES-C)on E51/DETDA epoxy and its carbon fiber composites(CFCs).Scanning electron microscopy showed that the phase structures of PES-C/epoxy blends change from island(of dispersed phase)structures to bi-continuous structures(of the matrix)as the PES-C content increased,which is associated with reaction-induced phase separation.After adding 15 phr PES-C,the glass transition temperature(T_(g))of the blends increased by 51.5℃,and the flexural strength,impact strength and fracture toughness of the blends were improved by 41.1%,186.2%and 42.7%,respectively.These improvements could be attributed to the phase separation structure of the PES-C/epoxy sys-tem.A PES-C film was used to improve the mode-II fracture toughness(G_(IIC))of CFCs.The G_(IIC) value of the 7μm PES-C film toughened laminate was improved by 80.3%compared to that of the control laminate.The increase in G_(IIC) was attributed to cohesive failure and plastic deformation in the interleaving region.展开更多
Glass-like carbons (GCs) were prepared by carbonization of acetone-furfural resin in nitrogen atmosphere at 850℃, followed by heat treatment over a range of 1 200-2 500℃in inert atmosphere. The effect of heat trea...Glass-like carbons (GCs) were prepared by carbonization of acetone-furfural resin in nitrogen atmosphere at 850℃, followed by heat treatment over a range of 1 200-2 500℃in inert atmosphere. The effect of heat treatment temperature (HTT) on the oxidation behavior was investigated by dynamic and isothermal thermogravimetric analyses. The structure of GC was examined by X-ray diffractometry (XRD) and the morphologies of GC before and after oxidation were examined by scanning electron microscopy (SEM). It is shown that the GC samples present peculiar oxidation behavior. The anti-oxidation behavior increases with increasing the HTT to 1 600 ℃, whereas decreases gradually thereafter. GC sample heat treated at 1 600℃ obtains relatively optimal anti-oxidation properties under this condition. During the oxidation, this material produces grid network matrix surface and numerous nodular residues on the surface, resulting in excellent resistance to the attack of oxygen atoms.展开更多
[Objective] The aim of this study was to investigate the decolorization ef- fects of activated carbon and macroporous resin on Periplaneta americana L. skimmed cream and compare the advantages and disadvantages of the...[Objective] The aim of this study was to investigate the decolorization ef- fects of activated carbon and macroporous resin on Periplaneta americana L. skimmed cream and compare the advantages and disadvantages of the two decolorization technologies. [Method] Periplaneta americana L. skimmed cream was decolored with activated carbon and macroporous resin, and freeze-dried to collect solid decolorization products. By investigating the yield, decolorization rate, protein retention rate and decolorization operation process, the advantages and disadvantages of the two decolorization technologies were compared. [Result] Both activated carbon and macroporous resin can be used for decolorization. To be specific, macroporous resin-decolorization is superior in the yield and protein retention rate, while activated carbon-decolorization is superior in decolorization rate and decolorization operation process. [Conclusion] Macroporous resin-decolorization can be used if protein is the main ingredient required in the experiment, while activated carbon-decolorization can be used if protein is not the main ingredient required.展开更多
[Objective] In this study, the feasibility of resins to extract antibacterial substances in ferrfientation broth of Micromonospora carbonacea JXNU-1 was investigated. Various parameters including the type of resin, th...[Objective] In this study, the feasibility of resins to extract antibacterial substances in ferrfientation broth of Micromonospora carbonacea JXNU-1 was investigated. Various parameters including the type of resin, the time of adsorption and the initial pH on the extraction efficiency were investigated and optimized. [Method] The antibacterial activity of antibiotics was determined by agar diffusion method. [Result] The 717 anion resin was selected as the optimal, and its adsorption capacity reached 1 221 U/g within 2.5 h at the acidic range of pH (pH 5). The Freundlich model was fit for the adsorption model of the 717 anion resin for antibiotics. [Conclusion] The results laid the foundation for further separating and purifying antibiotics in fermentation broth of Micromonospora carbonacea JXNU-1.展开更多
Resin matrix carbon brush composites(RMCBCs)are critical materials for high-powered electric tools.However,effectively improving their wear resistance and heat dissipation remains a challenge.RMCBCs prepared with flak...Resin matrix carbon brush composites(RMCBCs)are critical materials for high-powered electric tools.However,effectively improving their wear resistance and heat dissipation remains a challenge.RMCBCs prepared with flake graphite powders that were evenly loaded with tungsten copper composite powder(RMCBCs-W@Cu)exhibited a low wear rate of 1.63 mm^(3)/h,exhibiting 48.6%reduction in the wear rate relative to RCMBCs without additives(RMCBCs-0).In addition,RMCBCs-W@Cu achieved a low friction coefficient of 0.243 and low electric spark grade.These findings indicate that tungsten copper composite powders provide particle reinforcement and generate a gradation effect for the epoxy resin(i.e.,connecting phase)in RMCBCs,which weakens the wear of RMCBCs caused by fatigue under a cyclic current-carrying wear.展开更多
Longwall mining is by far the most common method of underground coal extraction in Australia. The industry trends and expectations are placing increasing emphasis on the reliability and productivity of these operation...Longwall mining is by far the most common method of underground coal extraction in Australia. The industry trends and expectations are placing increasing emphasis on the reliability and productivity of these operations. The longwalls are becoming wider and longer while retreat rates are continuously increasing due to significant improvements achieved in longwall equipment reliability and automation.This increased longwall productivity is placing significant emphasis on the reliability of longwall panel development. Although there have been significant improvements in the reliability of continuous miners and hydraulic drill rigs,the traditional resin encapsulated bolt installation is still the principal method used in all major coal-producing countries around the world. Anglo American realised an opportunity existed to introduce an alternative roof bolt installation technique called ‘‘spin to stall" in Australia.Spin to stall was first introduced in Anglo American Coal in South Africa where it has been successfully used for over a decade,though implementation of South African spin to stall resin in Australia has proven to be near impossible due to a significant difference in geotechnical conditions,mining method,and,subsequently,roof bolting equipment. Therefore,a new spin to stall development project was initiated between Anglo American Coal and Jennmar Australia(SPIN2STALLò). This paper summarises the journey of this project,the results,and the successful implementation of spin to stall achieved at Grasstree Mine.展开更多
Porous materials have regular three-dimensional pore structure, which has unique advantages in the field of modern pharmaceutical. At present, porous materials commonly used in the pharmaceutical field are mainly mole...Porous materials have regular three-dimensional pore structure, which has unique advantages in the field of modern pharmaceutical. At present, porous materials commonly used in the pharmaceutical field are mainly molecular sieves, macroporous adsorbent resins, activated carbon, etc. In this paper, the application status of these porous materials in the pharmaceutical field is reviewed, and the future development is prospected.展开更多
文摘A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various applications.We investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfone)(PES-C)on E51/DETDA epoxy and its carbon fiber composites(CFCs).Scanning electron microscopy showed that the phase structures of PES-C/epoxy blends change from island(of dispersed phase)structures to bi-continuous structures(of the matrix)as the PES-C content increased,which is associated with reaction-induced phase separation.After adding 15 phr PES-C,the glass transition temperature(T_(g))of the blends increased by 51.5℃,and the flexural strength,impact strength and fracture toughness of the blends were improved by 41.1%,186.2%and 42.7%,respectively.These improvements could be attributed to the phase separation structure of the PES-C/epoxy sys-tem.A PES-C film was used to improve the mode-II fracture toughness(G_(IIC))of CFCs.The G_(IIC) value of the 7μm PES-C film toughened laminate was improved by 80.3%compared to that of the control laminate.The increase in G_(IIC) was attributed to cohesive failure and plastic deformation in the interleaving region.
基金Project (2006CB600902) supported by the National Basic Research Program of China
文摘Glass-like carbons (GCs) were prepared by carbonization of acetone-furfural resin in nitrogen atmosphere at 850℃, followed by heat treatment over a range of 1 200-2 500℃in inert atmosphere. The effect of heat treatment temperature (HTT) on the oxidation behavior was investigated by dynamic and isothermal thermogravimetric analyses. The structure of GC was examined by X-ray diffractometry (XRD) and the morphologies of GC before and after oxidation were examined by scanning electron microscopy (SEM). It is shown that the GC samples present peculiar oxidation behavior. The anti-oxidation behavior increases with increasing the HTT to 1 600 ℃, whereas decreases gradually thereafter. GC sample heat treated at 1 600℃ obtains relatively optimal anti-oxidation properties under this condition. During the oxidation, this material produces grid network matrix surface and numerous nodular residues on the surface, resulting in excellent resistance to the attack of oxygen atoms.
基金Supported by National Natural Science Foundation of China(30560181)~~
文摘[Objective] The aim of this study was to investigate the decolorization ef- fects of activated carbon and macroporous resin on Periplaneta americana L. skimmed cream and compare the advantages and disadvantages of the two decolorization technologies. [Method] Periplaneta americana L. skimmed cream was decolored with activated carbon and macroporous resin, and freeze-dried to collect solid decolorization products. By investigating the yield, decolorization rate, protein retention rate and decolorization operation process, the advantages and disadvantages of the two decolorization technologies were compared. [Result] Both activated carbon and macroporous resin can be used for decolorization. To be specific, macroporous resin-decolorization is superior in the yield and protein retention rate, while activated carbon-decolorization is superior in decolorization rate and decolorization operation process. [Conclusion] Macroporous resin-decolorization can be used if protein is the main ingredient required in the experiment, while activated carbon-decolorization can be used if protein is not the main ingredient required.
基金Supported by the National Natural Science Foundation of China(31360018,31160029)the Natural Science Foundation of Jiangxi Province(20132BAB204007,20122BAB204008)+1 种基金Science and Technology Planning Project from Educational Commission of Jiangxi Province(GJJ12181)Special Fund for Agro-scientific Research in the Public Interest(201203072)~~
文摘[Objective] In this study, the feasibility of resins to extract antibacterial substances in ferrfientation broth of Micromonospora carbonacea JXNU-1 was investigated. Various parameters including the type of resin, the time of adsorption and the initial pH on the extraction efficiency were investigated and optimized. [Method] The antibacterial activity of antibiotics was determined by agar diffusion method. [Result] The 717 anion resin was selected as the optimal, and its adsorption capacity reached 1 221 U/g within 2.5 h at the acidic range of pH (pH 5). The Freundlich model was fit for the adsorption model of the 717 anion resin for antibiotics. [Conclusion] The results laid the foundation for further separating and purifying antibiotics in fermentation broth of Micromonospora carbonacea JXNU-1.
基金Projects(51772081,51837009,51971091)supported by the National Natural Science Foundation of ChinaProject(HFZL2018CXY003-4)supported by the Industry-University-Research Cooperation of AECC,ChinaProject(kq1902046)supported by the Major Science and Technology Projects of Changsha City,China。
文摘Resin matrix carbon brush composites(RMCBCs)are critical materials for high-powered electric tools.However,effectively improving their wear resistance and heat dissipation remains a challenge.RMCBCs prepared with flake graphite powders that were evenly loaded with tungsten copper composite powder(RMCBCs-W@Cu)exhibited a low wear rate of 1.63 mm^(3)/h,exhibiting 48.6%reduction in the wear rate relative to RCMBCs without additives(RMCBCs-0).In addition,RMCBCs-W@Cu achieved a low friction coefficient of 0.243 and low electric spark grade.These findings indicate that tungsten copper composite powders provide particle reinforcement and generate a gradation effect for the epoxy resin(i.e.,connecting phase)in RMCBCs,which weakens the wear of RMCBCs caused by fatigue under a cyclic current-carrying wear.
文摘Longwall mining is by far the most common method of underground coal extraction in Australia. The industry trends and expectations are placing increasing emphasis on the reliability and productivity of these operations. The longwalls are becoming wider and longer while retreat rates are continuously increasing due to significant improvements achieved in longwall equipment reliability and automation.This increased longwall productivity is placing significant emphasis on the reliability of longwall panel development. Although there have been significant improvements in the reliability of continuous miners and hydraulic drill rigs,the traditional resin encapsulated bolt installation is still the principal method used in all major coal-producing countries around the world. Anglo American realised an opportunity existed to introduce an alternative roof bolt installation technique called ‘‘spin to stall" in Australia.Spin to stall was first introduced in Anglo American Coal in South Africa where it has been successfully used for over a decade,though implementation of South African spin to stall resin in Australia has proven to be near impossible due to a significant difference in geotechnical conditions,mining method,and,subsequently,roof bolting equipment. Therefore,a new spin to stall development project was initiated between Anglo American Coal and Jennmar Australia(SPIN2STALLò). This paper summarises the journey of this project,the results,and the successful implementation of spin to stall achieved at Grasstree Mine.
文摘Porous materials have regular three-dimensional pore structure, which has unique advantages in the field of modern pharmaceutical. At present, porous materials commonly used in the pharmaceutical field are mainly molecular sieves, macroporous adsorbent resins, activated carbon, etc. In this paper, the application status of these porous materials in the pharmaceutical field is reviewed, and the future development is prospected.