The potassium-feldspar can be decomposed using the KOH as additive via hydrothermal synthesis methods, which can destroy the structure of the potassium-feldspar and turns its K+ into water soluble potash resources and...The potassium-feldspar can be decomposed using the KOH as additive via hydrothermal synthesis methods, which can destroy the structure of the potassium-feldspar and turns its K+ into water soluble potash resources and make its silica component utilized. The potassium-feldspar from Inner Mogolia was decomposed after iron removing and hydrothermal processes successively. The results showed(Table 1) that the iron could be removed up to 98.56% after the treatment of 90℃ for 2 hours with 5.8mol/L density of HCL solution. It is seen from the Table 1that the content of iron significantly decreased while the content of SiO2, Al2O3, K2O increase. The treated sample was used to be decomposed by hydrothermal method in KOH solution. The results showed that the dissolution rate of SiO2 could be up to 64.73% after the hydrothermal treatment of 260 ℃ for 2 hours with 1.2 mol/L density of KOH(Fig 1). The solid product is mailnly kalsilite phase.展开更多
Carbon with its high electrical conductivity,excellent chemical stability,and structure ability is the most promising an-ode material for sodium and potassium ion batteries.We developed a defect-rich porous carbon fra...Carbon with its high electrical conductivity,excellent chemical stability,and structure ability is the most promising an-ode material for sodium and potassium ion batteries.We developed a defect-rich porous carbon framework(DRPCF)built with N/O-co-doped mesoporous nanosheets and containing many defects using porous g-C_(3)N_(4)(PCN)and dopamine(DA)as raw materials.We prepared samples with PCN/DA mass ratios of 1/1,2/1 and 3/1 and found that the one with a mass ratio of 2/1 and a carbonization temperature of 700℃ in an Ar atmosphere(DRPCF-2/1-700),had a large specific surface area with an enormous pore volume and a large number of N/O heteroatom active defect sites.Because of this,it had the best pseudocapacitive sodium and potassium ion stor-age performance.A half battery of Na//DRPCF-2/1-700 maintained a capacity of 328.2 mAh g^(-1) after being cycled at 1 A g^(-1) for 900 cycles,and a half battery of K//DRPC-2/1-700 maintained a capacity of 321.5 mAh g^(-1) after being cycled at 1 A g^(-1) for 1200 cycles.The rate capability and cycling stability achieved by DRPCF-2/1-700 outperforms most reported carbon materials.Finally,ex-situ Raman spectroscopy analysis result confirms that the filling and removing of K^(+)and Na^(+)from the electrochemically active defects are responsible for the high capacity,superior rate and cycling performance of the DRPCF-2/1-700 sample.展开更多
Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge....Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.We present a microwave-assisted approach for its continuous,large-scale production which enables synthesis at a rate of 0.6 g/h,with a yield of up to 90%.The synthesized GDY nanosheets have an average diameter of 246 nm and a thickness of 4 nm.We used GDY as a stable coating for potassium(K)metal anodes(K@GDY),taking advantage of its unique molecular structure to provide favorable paths for K-ion transport.This modification significantly inhibited dendrite formation and improved the cycling stability of K metal batteries.Full-cells with perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA)cathodes showed the clear superiority of the K@GDY anodes over bare K anodes in terms of performance,stability,and cycle life.The K@GDY maintained a stable voltage plateau and gave an excellent capacity retention after 600 cycles with nearly 100%Coulombic efficiency.This work not only provides a scalable and efficient way for GDY synthesis but also opens new possibilities for its use in energy storage and other advanced technologies.展开更多
采用简单团簇模型结合密度泛函理论研究了CH3OH在Ga-rich Ga As(001)-(4×2)表面上的吸附与解离过程.计算结果表明,CH3OH在Ga-rich Ga As(001)-(4×2)表面上首先会形成两种化学吸附状态,然后CH3OH经解离生成CH3O自由基和H原子...采用简单团簇模型结合密度泛函理论研究了CH3OH在Ga-rich Ga As(001)-(4×2)表面上的吸附与解离过程.计算结果表明,CH3OH在Ga-rich Ga As(001)-(4×2)表面上首先会形成两种化学吸附状态,然后CH3OH经解离生成CH3O自由基和H原子吸附在表面不同位置上.通过比较各个吸附解离路径,发现解离后的H原子相对更容易吸附在位于表面第二层紧邻的As原子上.展开更多
The present study aims at the recovery of potassium from muscovite mica(which contains K_(2)O;~10 wt%)using NaCl-roasting coupled with H_(2)SO_(4)-leaching process.The preliminary acid leaching studies applying differ...The present study aims at the recovery of potassium from muscovite mica(which contains K_(2)O;~10 wt%)using NaCl-roasting coupled with H_(2)SO_(4)-leaching process.The preliminary acid leaching studies applying different mineral acids resulted in a potassium recovery of 8%−18%.The optimum leaching conditions for the maximum recovery were 4 mol/L H_(2)SO_(4),60 min leaching time and liquid-solid ratio 4 mL/g at 90℃.However,the roasting of muscovite with additive NaCl(muscovite:NaCl mass ratio of 1:1.00,900℃,45 min)followed by H_(2)SO_(4)-leaching(95℃,60 min)extracted potassium to the tune of 98%.Under similar roasting conditions,the H_(2)O-leaching process extracted only 60%of potassium.The effects of various roasting and leaching parameters such as temperature,time,NaCl concentration,acid concentration,liquid-solid ratio on potassium extraction were evaluated.The appearance of the sylvite(KCl)mineral phase in the NaCl-roasted muscovite and its disappearance in the acid/water leached residue confirmed the physical and chemical distortions of the muscovite crystal structure.The possible mechanism of potassium release from the complex muscovite structure was elucidated based on available literature substantiated by characterizations using X-ray diffraction(XRD)and scanning electron microscopy with energy dispersive X-rays spectroscopy(SEM-EDX).展开更多
The Yunnan Himalayan alkaline rich porphyry occurs as a compound rockbelt and consists of calca alkalic, alkaline and peralkaline intrusions. Its origin is in debate. The paper deals with its origin by studying rock′...The Yunnan Himalayan alkaline rich porphyry occurs as a compound rockbelt and consists of calca alkalic, alkaline and peralkaline intrusions. Its origin is in debate. The paper deals with its origin by studying rock′s REE and Sr isotope. Although the rocks are different in their REE contents varying from 77.53 μg/g to 1 798.3 μg/g, they have very similar features in REE parameters. On the triangalar diagram of REEs, the sample dots are concentrated on the end area of light REEs, representing a product of low degree melting of upper mantle or lower crust materials. The initial 87 Sr/ 86 Sr values of rocks vary between 0.706 4 and 0.709 8, showing a feature of mantle crust mixed source. Moreover, REEs show a logarithmic linear positive correlation between them. This type of correlation strongly supports the fractional partial melting model. The result of geochemistry inversion shows that the source rock of alkaline rich porphyry is plagioclase bearing harzburgite and of mantle crust mixed type. At the early state of melting, some crust components of the source rock were partially melted into intermediate acidic magma; with the crust components consumed, the magma evolved to basic.展开更多
Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig...Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.展开更多
Background Under K deficiency the uptake and distribution pattern in plant cells is mediated through different transport proteins and channels which were controlled by specific gene family.Therefore,a hydroponic exper...Background Under K deficiency the uptake and distribution pattern in plant cells is mediated through different transport proteins and channels which were controlled by specific gene family.Therefore,a hydroponic experiment was conducted under control condition for testing the gene expression pattern of the K transporter under adequate and low K supply levels.After that,a 2-year field experiment was conducted to evaluate five selected cotton cultivars(four K-efficient cultivars,viz.,CIM-554,CYTO-124,FH-142,IUB-2013,and one K non-efficient,BH-212) screened from the initial hydroponics culture experiment and two levels of potassium(0 K_(2)O kg·ha^(-1) and 50 K_(2)O kg·ha^(-1)) were tested under reduced irrigation(50% available water content;50 AWC) and normal irrigation conditions(100% available water content;100 AWC).Result Results revealed that the transcript levels of GhHAK5aD in roots were significantly higher in K^(+) efficient cultivars than that in K^(+) non-efficient cultivars.The GhHAK5aD expression upon K^(+) deficiency was higher in roots but lower in shoots,indicating that GhHAK5aD could have a role in K^(+) uptake in roots,instead of transport of K^(+) from root to shoot.Similarly,under field conditions the cultivar FH-142 showed an increase of 22.3%,4.9%,2.4%,and 1.4% as compared with BH-212,IUB-2013,CYTO-124,and CIM-554,respectively,in seed cotton yield(SCY) with K application under reduced irrigation conditions.With applied K,the FH-142 showed an increase in net photosynthetic rate by 57.3% as compared with the rest of the cultivars under reduced irrigation over K control.However,the overall performance indicators of K-efficient cultivars like FH-142,CYTO-124,CIM-554,and IUB-2013 were better than BH-212(K in-efficient) under reduced irrigation conditions with applied K at 50 kg·ha^(-1).Fiber quality trait improved significantly with K application under water deficit.The increase in micronaire was 3.6%,4.7%,7.8%,3.4%,and 6.7% in BH-212,IUB-2013,CIM-554,CYTO-124,and FH-142,respectively,with K application at 50 kg·ha^(-1) over without K application under reduced irrigation conditions during the cotton growing season.Similarly,the cultivars FH-142 increased by 12% with K application under reduced irrigation as compared with other cultivars.The performance of K-efficient cultivars under reduced irrigation conditions was 30% better in SCY and quality traits with the application of K at 50 kg·ha^(-1) as compared with K-non-efficient cultivars.Similarly,water use efficiency(WUE)(40.1%) and potassium use efficiency(KUE)(20.2%) were also noted higher in case of FH-142 as compared with other cultivar with K application under reduced conditions.Conclusion Higher expression of GhHAK5aD gene was observed in K-efficient cultivars as compared with K-nonefficient cultivars in roots indicates that GhHAK5aD may be contributing to genotypic differences for K^(+) efficiency in cotton.K-efficient cotton cultivars can be used for the low-K environments and can also be recommended for general cultivars.展开更多
基金Project supported by National Key Technologies Research and Development Program for 11th Five-year Plan(No. 2006BAD10B04)China Geological Survey Project(No. 12120113087700)
文摘The potassium-feldspar can be decomposed using the KOH as additive via hydrothermal synthesis methods, which can destroy the structure of the potassium-feldspar and turns its K+ into water soluble potash resources and make its silica component utilized. The potassium-feldspar from Inner Mogolia was decomposed after iron removing and hydrothermal processes successively. The results showed(Table 1) that the iron could be removed up to 98.56% after the treatment of 90℃ for 2 hours with 5.8mol/L density of HCL solution. It is seen from the Table 1that the content of iron significantly decreased while the content of SiO2, Al2O3, K2O increase. The treated sample was used to be decomposed by hydrothermal method in KOH solution. The results showed that the dissolution rate of SiO2 could be up to 64.73% after the hydrothermal treatment of 260 ℃ for 2 hours with 1.2 mol/L density of KOH(Fig 1). The solid product is mailnly kalsilite phase.
文摘Carbon with its high electrical conductivity,excellent chemical stability,and structure ability is the most promising an-ode material for sodium and potassium ion batteries.We developed a defect-rich porous carbon framework(DRPCF)built with N/O-co-doped mesoporous nanosheets and containing many defects using porous g-C_(3)N_(4)(PCN)and dopamine(DA)as raw materials.We prepared samples with PCN/DA mass ratios of 1/1,2/1 and 3/1 and found that the one with a mass ratio of 2/1 and a carbonization temperature of 700℃ in an Ar atmosphere(DRPCF-2/1-700),had a large specific surface area with an enormous pore volume and a large number of N/O heteroatom active defect sites.Because of this,it had the best pseudocapacitive sodium and potassium ion stor-age performance.A half battery of Na//DRPCF-2/1-700 maintained a capacity of 328.2 mAh g^(-1) after being cycled at 1 A g^(-1) for 900 cycles,and a half battery of K//DRPC-2/1-700 maintained a capacity of 321.5 mAh g^(-1) after being cycled at 1 A g^(-1) for 1200 cycles.The rate capability and cycling stability achieved by DRPCF-2/1-700 outperforms most reported carbon materials.Finally,ex-situ Raman spectroscopy analysis result confirms that the filling and removing of K^(+)and Na^(+)from the electrochemically active defects are responsible for the high capacity,superior rate and cycling performance of the DRPCF-2/1-700 sample.
基金supported by National Natural Science Foundation of China(52302034,52402060,52202201,52021006)Beijing National Laboratory for Molecular Sciences(BNLMS-CXTD202001)+1 种基金Shenzhen Science and Technology Innovation Commission(KQTD20221101115627004)China Postdoctoral Science Foundation(2024T170972)。
文摘Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.We present a microwave-assisted approach for its continuous,large-scale production which enables synthesis at a rate of 0.6 g/h,with a yield of up to 90%.The synthesized GDY nanosheets have an average diameter of 246 nm and a thickness of 4 nm.We used GDY as a stable coating for potassium(K)metal anodes(K@GDY),taking advantage of its unique molecular structure to provide favorable paths for K-ion transport.This modification significantly inhibited dendrite formation and improved the cycling stability of K metal batteries.Full-cells with perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA)cathodes showed the clear superiority of the K@GDY anodes over bare K anodes in terms of performance,stability,and cycle life.The K@GDY maintained a stable voltage plateau and gave an excellent capacity retention after 600 cycles with nearly 100%Coulombic efficiency.This work not only provides a scalable and efficient way for GDY synthesis but also opens new possibilities for its use in energy storage and other advanced technologies.
文摘采用简单团簇模型结合密度泛函理论研究了CH3OH在Ga-rich Ga As(001)-(4×2)表面上的吸附与解离过程.计算结果表明,CH3OH在Ga-rich Ga As(001)-(4×2)表面上首先会形成两种化学吸附状态,然后CH3OH经解离生成CH3O自由基和H原子吸附在表面不同位置上.通过比较各个吸附解离路径,发现解离后的H原子相对更容易吸附在位于表面第二层紧邻的As原子上.
文摘The present study aims at the recovery of potassium from muscovite mica(which contains K_(2)O;~10 wt%)using NaCl-roasting coupled with H_(2)SO_(4)-leaching process.The preliminary acid leaching studies applying different mineral acids resulted in a potassium recovery of 8%−18%.The optimum leaching conditions for the maximum recovery were 4 mol/L H_(2)SO_(4),60 min leaching time and liquid-solid ratio 4 mL/g at 90℃.However,the roasting of muscovite with additive NaCl(muscovite:NaCl mass ratio of 1:1.00,900℃,45 min)followed by H_(2)SO_(4)-leaching(95℃,60 min)extracted potassium to the tune of 98%.Under similar roasting conditions,the H_(2)O-leaching process extracted only 60%of potassium.The effects of various roasting and leaching parameters such as temperature,time,NaCl concentration,acid concentration,liquid-solid ratio on potassium extraction were evaluated.The appearance of the sylvite(KCl)mineral phase in the NaCl-roasted muscovite and its disappearance in the acid/water leached residue confirmed the physical and chemical distortions of the muscovite crystal structure.The possible mechanism of potassium release from the complex muscovite structure was elucidated based on available literature substantiated by characterizations using X-ray diffraction(XRD)and scanning electron microscopy with energy dispersive X-rays spectroscopy(SEM-EDX).
文摘The Yunnan Himalayan alkaline rich porphyry occurs as a compound rockbelt and consists of calca alkalic, alkaline and peralkaline intrusions. Its origin is in debate. The paper deals with its origin by studying rock′s REE and Sr isotope. Although the rocks are different in their REE contents varying from 77.53 μg/g to 1 798.3 μg/g, they have very similar features in REE parameters. On the triangalar diagram of REEs, the sample dots are concentrated on the end area of light REEs, representing a product of low degree melting of upper mantle or lower crust materials. The initial 87 Sr/ 86 Sr values of rocks vary between 0.706 4 and 0.709 8, showing a feature of mantle crust mixed source. Moreover, REEs show a logarithmic linear positive correlation between them. This type of correlation strongly supports the fractional partial melting model. The result of geochemistry inversion shows that the source rock of alkaline rich porphyry is plagioclase bearing harzburgite and of mantle crust mixed type. At the early state of melting, some crust components of the source rock were partially melted into intermediate acidic magma; with the crust components consumed, the magma evolved to basic.
文摘Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.
文摘Background Under K deficiency the uptake and distribution pattern in plant cells is mediated through different transport proteins and channels which were controlled by specific gene family.Therefore,a hydroponic experiment was conducted under control condition for testing the gene expression pattern of the K transporter under adequate and low K supply levels.After that,a 2-year field experiment was conducted to evaluate five selected cotton cultivars(four K-efficient cultivars,viz.,CIM-554,CYTO-124,FH-142,IUB-2013,and one K non-efficient,BH-212) screened from the initial hydroponics culture experiment and two levels of potassium(0 K_(2)O kg·ha^(-1) and 50 K_(2)O kg·ha^(-1)) were tested under reduced irrigation(50% available water content;50 AWC) and normal irrigation conditions(100% available water content;100 AWC).Result Results revealed that the transcript levels of GhHAK5aD in roots were significantly higher in K^(+) efficient cultivars than that in K^(+) non-efficient cultivars.The GhHAK5aD expression upon K^(+) deficiency was higher in roots but lower in shoots,indicating that GhHAK5aD could have a role in K^(+) uptake in roots,instead of transport of K^(+) from root to shoot.Similarly,under field conditions the cultivar FH-142 showed an increase of 22.3%,4.9%,2.4%,and 1.4% as compared with BH-212,IUB-2013,CYTO-124,and CIM-554,respectively,in seed cotton yield(SCY) with K application under reduced irrigation conditions.With applied K,the FH-142 showed an increase in net photosynthetic rate by 57.3% as compared with the rest of the cultivars under reduced irrigation over K control.However,the overall performance indicators of K-efficient cultivars like FH-142,CYTO-124,CIM-554,and IUB-2013 were better than BH-212(K in-efficient) under reduced irrigation conditions with applied K at 50 kg·ha^(-1).Fiber quality trait improved significantly with K application under water deficit.The increase in micronaire was 3.6%,4.7%,7.8%,3.4%,and 6.7% in BH-212,IUB-2013,CIM-554,CYTO-124,and FH-142,respectively,with K application at 50 kg·ha^(-1) over without K application under reduced irrigation conditions during the cotton growing season.Similarly,the cultivars FH-142 increased by 12% with K application under reduced irrigation as compared with other cultivars.The performance of K-efficient cultivars under reduced irrigation conditions was 30% better in SCY and quality traits with the application of K at 50 kg·ha^(-1) as compared with K-non-efficient cultivars.Similarly,water use efficiency(WUE)(40.1%) and potassium use efficiency(KUE)(20.2%) were also noted higher in case of FH-142 as compared with other cultivar with K application under reduced conditions.Conclusion Higher expression of GhHAK5aD gene was observed in K-efficient cultivars as compared with K-nonefficient cultivars in roots indicates that GhHAK5aD may be contributing to genotypic differences for K^(+) efficiency in cotton.K-efficient cotton cultivars can be used for the low-K environments and can also be recommended for general cultivars.
