Two distinct copper coordination polymers, namely [Cu^Ⅱ2(2,5-pydc)2(bpp)2]·H2O(1) and Cu2^ⅠCu^Ⅱ(2,5-pydc)2(bpp)2(2)(2,5-pydc = pyridine-2,5-dicarboxylic acid, bpp = 1,3-bi(4-pyridyl)propane), h...Two distinct copper coordination polymers, namely [Cu^Ⅱ2(2,5-pydc)2(bpp)2]·H2O(1) and Cu2^ⅠCu^Ⅱ(2,5-pydc)2(bpp)2(2)(2,5-pydc = pyridine-2,5-dicarboxylic acid, bpp = 1,3-bi(4-pyridyl)propane), have been successfully synthesized through hydrothermal conditions under different temperatures. Single-crystal X-ray structural analysis revealed that both complexes 1 and 2 are 3D frameworks. Complex 1 is an 8-connected 2-fold interpenetrating network based on [Cu(2,5-pydc)]4 molecular building block(MBB), and also can be simplified as a 4-connected net if the Cu(Ⅱ) ion is regarded as an independent node, whereas 2 shows a(4,4)-connected non-interpenetrated framework which contains mixed valence Cu(Ⅰ/Ⅱ) centers. The results demonstrate that temperature plays a significant role in the final structures of the complexes.展开更多
Single-phase insulating 12CaO?7Al_2O_3(C12A7) powder was synthesized using an optimized hydrothermal method. Pure phase of C12A7 was got at a comparatively lower temperature(c.a. 300 ℃) than that has been previo...Single-phase insulating 12CaO?7Al_2O_3(C12A7) powder was synthesized using an optimized hydrothermal method. Pure phase of C12A7 was got at a comparatively lower temperature(c.a. 300 ℃) than that has been previously reported. The crystallite size of the synthesized C12A7 powder was 7±2 nm. The surface area values calculated for all the samples at a synthesis temperature range of 250-800 ℃ for 5 h were in the range of about 19-24 m^2/g, with pore sizes of 12-20 nm. This low-temperature-based synthetic strategy along with nano porous structures and a high surface area value can facilitate catalyst application.展开更多
Hydrothermal carbonization of animal manure is being increasingly recognized as a green process for hydrochar production.Temperature obviously affects the properties of hydrochar especially with respect to carbon rete...Hydrothermal carbonization of animal manure is being increasingly recognized as a green process for hydrochar production.Temperature obviously affects the properties of hydrochar especially with respect to carbon retention and stability.These properties determine the carbon sequestration potential of hydrochar but related researches are limited.In this study,chicken,dairy,and swine manures were collected and hydrothermal carbonized under different temperature conditions,aiming to study the fuel characteristics,carbon retention,and stability of hydrochar influenced by temperature.Results show that high temperature led to low yield and declined H/C,O/C,and volatile matter of hydrochar.While high temperature caused high fixed carbon,fuel ratio,and heating value of hydrochar,indicating that animal manure hydrochar can be adopted as an alternative of fuel.After hydrothermal carbonization,less than half of carbon from animal manure was retained in hydrochar:22.70%-46.71%for chicken manure,39.36%-49.72%for dairy manure,and 36.24%-64.21%for swine manure.The carbon retention decreased with the increase of temperature.Conversely,high temperature improved the aromatic and strengthened the resistance to thermal oxidation of hydrochar,which was evidenced by FTIR and TGA analysis.Moreover,the carbon sequestration capacity of animal manure hydrochar was less than a third of total carbon(originated from animal manure)and relatively low temperature(no more than 250℃)was beneficial to produce hydrochar for carbon sequestration.展开更多
(Na, K)NbO3 (KNN) powders were successfully prepared by high temperature mixing method (HTMM) under hydrothermal conditions to study the effect of reaction time on the formation of KNN for three K+/(K+ +Na+...(Na, K)NbO3 (KNN) powders were successfully prepared by high temperature mixing method (HTMM) under hydrothermal conditions to study the effect of reaction time on the formation of KNN for three K+/(K+ +Na+) ratios of 0.6, 0.7 and 0.8. The products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), to show the change of phase and morphology of the as-prepared particles with the K+/(K+ + Na+) molar ratio in the solution. Pure Na-rich KNN monoclinic phase and pure K-rich KNN orthorhombic phase could be obtained quickly after mixing the solutions at high temperature when the K+/(K+ +Na+) molar ratio was either 0.6 or 0.8. When the K+/(K+ +Na+) molar ratio was 0.7, however, the K-rich KNN orthorhombic phase grain formed first, followed by the Na-rich KNN monoclinic phase grain, with the two phases coexisting in the final product.展开更多
The relatively poor corrosion resistance remarkably limits the wide applications of Mg alloys in practice,although they possess many attractive properties,like low density,high specific strength,and good biocompatibil...The relatively poor corrosion resistance remarkably limits the wide applications of Mg alloys in practice,although they possess many attractive properties,like low density,high specific strength,and good biocompatibility.The formation of a protective coating can effectively suppress the corrosion.In this work,a slippery liquid-infused porous surface(SLIPS),with good surface hydrophobicity,stability,and self-healing property,was formed on AZ31 Mg alloys.The development of SLIPS requires suitable porous micro/nanostructures.Layered double hydroxide(LDH),with effective corrosion resistance for Mg alloys,was a good candidate to accommodate the liquid lubricant.Especially,different temperatures were applied to in situ form MgAl-LDH on AZ31 Mg alloys.The results showed that the temperature of 120℃was the best condition for the SLIPS to provide good corrosion protection for Mg alloys,with the lowest corrosion current density of 3.19×10^(-9)A cm^(−2).In addition,the SLIPS performed well in the long-term immersion test and abrasion test.The AZ31 Mg alloys with superior corrosion resistance and good mechanical and chemical stability can be extensively applied in areas of automotive,electronics,and aerospace.展开更多
基金supported by the application basis research key project of Yunnan Province science and technology department(201401CB00299)the major project of Qujing Normal University(2012ZD002)
文摘Two distinct copper coordination polymers, namely [Cu^Ⅱ2(2,5-pydc)2(bpp)2]·H2O(1) and Cu2^ⅠCu^Ⅱ(2,5-pydc)2(bpp)2(2)(2,5-pydc = pyridine-2,5-dicarboxylic acid, bpp = 1,3-bi(4-pyridyl)propane), have been successfully synthesized through hydrothermal conditions under different temperatures. Single-crystal X-ray structural analysis revealed that both complexes 1 and 2 are 3D frameworks. Complex 1 is an 8-connected 2-fold interpenetrating network based on [Cu(2,5-pydc)]4 molecular building block(MBB), and also can be simplified as a 4-connected net if the Cu(Ⅱ) ion is regarded as an independent node, whereas 2 shows a(4,4)-connected non-interpenetrated framework which contains mixed valence Cu(Ⅰ/Ⅱ) centers. The results demonstrate that temperature plays a significant role in the final structures of the complexes.
基金Funded by the National Natural Science Foundation of China(No.21377063)the Zhejiang Natural Science Foundation(No.LY15F040004)the Program for Ningbo Key Laboratory of Silicon and Organic Thin Film Optoelectronic Technologies
文摘Single-phase insulating 12CaO?7Al_2O_3(C12A7) powder was synthesized using an optimized hydrothermal method. Pure phase of C12A7 was got at a comparatively lower temperature(c.a. 300 ℃) than that has been previously reported. The crystallite size of the synthesized C12A7 powder was 7±2 nm. The surface area values calculated for all the samples at a synthesis temperature range of 250-800 ℃ for 5 h were in the range of about 19-24 m^2/g, with pore sizes of 12-20 nm. This low-temperature-based synthetic strategy along with nano porous structures and a high surface area value can facilitate catalyst application.
基金the support of the Anhui Science and Technology Major Project(Grant No.201903a06020023)the Natural Science Research Project of Colleges and Universities in Anhui Province(Grant No.KJ2020A0049)+1 种基金the Anhui Province University Top Talent Funding Project(Grant No.gxbjZD2021069)the Commissioned R&D Project(Grant No.ZHEP2021001,No.BOFA202007).
文摘Hydrothermal carbonization of animal manure is being increasingly recognized as a green process for hydrochar production.Temperature obviously affects the properties of hydrochar especially with respect to carbon retention and stability.These properties determine the carbon sequestration potential of hydrochar but related researches are limited.In this study,chicken,dairy,and swine manures were collected and hydrothermal carbonized under different temperature conditions,aiming to study the fuel characteristics,carbon retention,and stability of hydrochar influenced by temperature.Results show that high temperature led to low yield and declined H/C,O/C,and volatile matter of hydrochar.While high temperature caused high fixed carbon,fuel ratio,and heating value of hydrochar,indicating that animal manure hydrochar can be adopted as an alternative of fuel.After hydrothermal carbonization,less than half of carbon from animal manure was retained in hydrochar:22.70%-46.71%for chicken manure,39.36%-49.72%for dairy manure,and 36.24%-64.21%for swine manure.The carbon retention decreased with the increase of temperature.Conversely,high temperature improved the aromatic and strengthened the resistance to thermal oxidation of hydrochar,which was evidenced by FTIR and TGA analysis.Moreover,the carbon sequestration capacity of animal manure hydrochar was less than a third of total carbon(originated from animal manure)and relatively low temperature(no more than 250℃)was beneficial to produce hydrochar for carbon sequestration.
基金supported by the National Natural Science Foundation of China(Nos.50872053,50830201)Program for New Century Excellent Talents in University(NCET-10-0070)Jiangsu Province Natural Science Foundation(No.BK2008399)
文摘(Na, K)NbO3 (KNN) powders were successfully prepared by high temperature mixing method (HTMM) under hydrothermal conditions to study the effect of reaction time on the formation of KNN for three K+/(K+ +Na+) ratios of 0.6, 0.7 and 0.8. The products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), to show the change of phase and morphology of the as-prepared particles with the K+/(K+ + Na+) molar ratio in the solution. Pure Na-rich KNN monoclinic phase and pure K-rich KNN orthorhombic phase could be obtained quickly after mixing the solutions at high temperature when the K+/(K+ +Na+) molar ratio was either 0.6 or 0.8. When the K+/(K+ +Na+) molar ratio was 0.7, however, the K-rich KNN orthorhombic phase grain formed first, followed by the Na-rich KNN monoclinic phase grain, with the two phases coexisting in the final product.
基金supported by the National Natural Science Foundation of China(No.52001036)the China Postdoctoral Science Foundation(Nos.2022T150767 and 2021M693708).
文摘The relatively poor corrosion resistance remarkably limits the wide applications of Mg alloys in practice,although they possess many attractive properties,like low density,high specific strength,and good biocompatibility.The formation of a protective coating can effectively suppress the corrosion.In this work,a slippery liquid-infused porous surface(SLIPS),with good surface hydrophobicity,stability,and self-healing property,was formed on AZ31 Mg alloys.The development of SLIPS requires suitable porous micro/nanostructures.Layered double hydroxide(LDH),with effective corrosion resistance for Mg alloys,was a good candidate to accommodate the liquid lubricant.Especially,different temperatures were applied to in situ form MgAl-LDH on AZ31 Mg alloys.The results showed that the temperature of 120℃was the best condition for the SLIPS to provide good corrosion protection for Mg alloys,with the lowest corrosion current density of 3.19×10^(-9)A cm^(−2).In addition,the SLIPS performed well in the long-term immersion test and abrasion test.The AZ31 Mg alloys with superior corrosion resistance and good mechanical and chemical stability can be extensively applied in areas of automotive,electronics,and aerospace.