The bimetallic catalyst Ru-Pt/ γ -Al 2O 3 was prepared by impregnating H 2PtCl 6 and RuCl 3 aqueous solution in the presence of PVP(40 000). Its catalytic performance in selective hydrogenation of \{ p -chloronitrobe...The bimetallic catalyst Ru-Pt/ γ -Al 2O 3 was prepared by impregnating H 2PtCl 6 and RuCl 3 aqueous solution in the presence of PVP(40 000). Its catalytic performance in selective hydrogenation of \{ p -chloronitrobenzene\}( p -CNB) was studied. The results indicate that the activity of Ru-Pt/ γ -Al 2O 3[\{ n (ruthenium)\}∶ n (platinum)=4∶1] is much higher than that of Ru/ γ -Al 2O 3,while the amount of dehalogenation product(aniline) and other by-products are much fewer than that by using Pt/ γ -Al 2O 3 as the catalyst. There is synergistic effect of ruthenium and platinum in bimetallic catalyst for selective hydrogenation of p -CNB. Under the reaction conditions t =50 ℃, p H 2 = 1.0 MPa, reaction time 60 min,\{ n (substrate)∶\} n (total amount of metal content)=1000∶1,the conversion of p -CNB and the selectivity to p -chloroaniline( p -CNA) by using Ru-Pt/ γ -Al 2O 3 as the catalyst are 48.2% and 85.9%,respectively. The effect of other metal cations(introduced to the reaction system with the corresponding metal chloride solution) on the reaction was investigated. It was found that catalytic performance of Ru-Pt/ γ -Al 2O 3 could be greatly improved by modfication of some metal cations. When Co 2+ and Ni 2+ were used as modifiers for the catalyst Ru-Pt/ γ -Al 2O 3 under above mentioned reaction conditions,the conversions of p -CNB increase to 74.5% and 87.8%,as well as the selectivities of p -CAN increase to 98.9% and 99.4%,respectively. Fe 3+ and Sn 4+ were the best modifiers for Ru-Pt/ γ -Al 2O 3 under the same reaction conditions. The conversions of p -CNB and the selectivities of p -CAN can reach 100% and >99.0%,respectively. However,the catalysts can be poisoned by Zn 2+ and Sn 2+ .展开更多
】目的 :构建小鼠蛋白激酶 CK2 β亚基 c DNA重组表达质粒 ,以便深入进行 CK2结构与功能的研究。方法 :通过反转录 PCR从 NIH3T3小鼠成纤维细胞中获得小鼠蛋白激酶 CK2 β亚基编码区 c DNA,PCR扩增酶为高保真 DNA聚合酶。将 N de I/ H i...】目的 :构建小鼠蛋白激酶 CK2 β亚基 c DNA重组表达质粒 ,以便深入进行 CK2结构与功能的研究。方法 :通过反转录 PCR从 NIH3T3小鼠成纤维细胞中获得小鼠蛋白激酶 CK2 β亚基编码区 c DNA,PCR扩增酶为高保真 DNA聚合酶。将 N de I/ H ind 彻底双酶切 PCR产物定向连接到牛小肠碱性磷酸酶去 5′端磷酸的同样彻底 Nde I/ H ind 双酶切的表达载体 p T7- 7中 ,转化感受态大肠杆菌 DH5 α获得转化子 ,用 0 .8%琼脂糖凝胶电泳初步筛选转化子 ,将阳性克隆进行单和双酶切分析鉴定。随机挑选两个阳性克隆进行 DNA测序。结果 :转化子的阳性筛选率为 10 0 % ,限制性酶切分析结果表明插入片段和重组质粒的大小与理论推测值相符。 DNA测序结果表明 :两个重组小鼠 CK2 β亚基克隆中的插入片段序列均与两种已报道的小鼠 CK2 β亚基 c DNA编码区序列分别存在一个碱基差异 ,但我们报道的这 2个差异碱基与大鼠、兔、猪和人 CK2 β亚基 c DNA的编码区相应碱基序列一致。结论 :本实验克隆的小鼠蛋白激酶 CK2 β亚基 c展开更多
The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000℃ and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K.We found that ...The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000℃ and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K.We found that Dy2Pt2O7 does not form long-range magnetic order,but displays characteristics of canonical spin ice such as Dy2Pt2O7,including(1)a large effective moment 9.64μB close to the theoretical value and a small positive Curie-Weiss temperatureθCW=+0.77 K signaling a dominant ferromagnetic interaction among the Ising spins;(2)a saturation moment ~4.5μB being half of the total moment due to the local<111>Ising anisotropy;(3)thermally activated spin relaxation behaviors in the low(~1 K)and high(~20 K)temperature regions with different energy barriers and characteristic relaxation time;and most importantly,(4)the presence of a residual entropy close to Pauling’s estimation for water ice.展开更多
A new type of philosophy and mathematics from the pansystems view is introduced here, including the 7 philosophy theories (7PT) and related mathematizing researches. Many second/third philosophies are developed within...A new type of philosophy and mathematics from the pansystems view is introduced here, including the 7 philosophy theories (7PT) and related mathematizing researches. Many second/third philosophies are developed within pansystems framework and related applications to APT MS.展开更多
A new type of philosophy and mathematics from the pansytems view is introduced here,including the 7 philosophic theories(7PT)and related mathematic researches.Many second/third philosophies are developed within pansvs...A new type of philosophy and mathematics from the pansytems view is introduced here,including the 7 philosophic theories(7PT)and related mathematic researches.Many second/third philosophies are developed within pansvstems framework and related applications to APTMS.展开更多
A new type of philosophy from the view of pansystems is introducedhere,including the 7 philosophy theories(7PT),fuzziness research andmany second/third philosophies are developed within pansystems frame-work.
Numerous researchers in the energy field are engaged in a competitive race to advance hydrogen as a clean and environmentally friendly fuel.Studies have been conducted on the different aspects of hydrogen,including it...Numerous researchers in the energy field are engaged in a competitive race to advance hydrogen as a clean and environmentally friendly fuel.Studies have been conducted on the different aspects of hydrogen,including its production,storage,transportation and utilization.The catalytic methane decomposition technique for hydrogen production is an environmentally friendly process that avoids generating carbon dioxide gas,which contributes to the greenhouse effect.Catalysts play a crucial role in facilitating rapid,cost-effective and efficient production of hydrogen using this technique.In this study,reactive molecular dynamics simulations were employed to examine the impact of Pt7 cluster decoration on the surface of a Ni(110)catalyst,referred to as Pt7-Ni(110),on the rates of methane dissociation and molecular hydrogen production.The reactive force field was employed to model the atomic interactions that enabled the formation and dissociation of chemical bonds.Our reactive molecular dynamics simulations using the Pt7-Ni(110)catalyst revealed a notable decrease in the number of methane molecules,specifically~11.89 molecules per picosecond.The rate was approximately four times higher than that of the simulation system utilizing a Ni(110)catalyst and approximately six times higher than that of the pure methane,no-catalyst system.The number of hydrogen molecules generated during a simulation period of 150000 fs was greater on the Pt7-Ni(110)surface than in both the Ni(110)and pure methane systems.This was due to the presence of numerous dissociated hydrogen atoms on the Pt7-Ni(110)surface.展开更多
文摘The bimetallic catalyst Ru-Pt/ γ -Al 2O 3 was prepared by impregnating H 2PtCl 6 and RuCl 3 aqueous solution in the presence of PVP(40 000). Its catalytic performance in selective hydrogenation of \{ p -chloronitrobenzene\}( p -CNB) was studied. The results indicate that the activity of Ru-Pt/ γ -Al 2O 3[\{ n (ruthenium)\}∶ n (platinum)=4∶1] is much higher than that of Ru/ γ -Al 2O 3,while the amount of dehalogenation product(aniline) and other by-products are much fewer than that by using Pt/ γ -Al 2O 3 as the catalyst. There is synergistic effect of ruthenium and platinum in bimetallic catalyst for selective hydrogenation of p -CNB. Under the reaction conditions t =50 ℃, p H 2 = 1.0 MPa, reaction time 60 min,\{ n (substrate)∶\} n (total amount of metal content)=1000∶1,the conversion of p -CNB and the selectivity to p -chloroaniline( p -CNA) by using Ru-Pt/ γ -Al 2O 3 as the catalyst are 48.2% and 85.9%,respectively. The effect of other metal cations(introduced to the reaction system with the corresponding metal chloride solution) on the reaction was investigated. It was found that catalytic performance of Ru-Pt/ γ -Al 2O 3 could be greatly improved by modfication of some metal cations. When Co 2+ and Ni 2+ were used as modifiers for the catalyst Ru-Pt/ γ -Al 2O 3 under above mentioned reaction conditions,the conversions of p -CNB increase to 74.5% and 87.8%,as well as the selectivities of p -CAN increase to 98.9% and 99.4%,respectively. Fe 3+ and Sn 4+ were the best modifiers for Ru-Pt/ γ -Al 2O 3 under the same reaction conditions. The conversions of p -CNB and the selectivities of p -CAN can reach 100% and >99.0%,respectively. However,the catalysts can be poisoned by Zn 2+ and Sn 2+ .
文摘】目的 :构建小鼠蛋白激酶 CK2 β亚基 c DNA重组表达质粒 ,以便深入进行 CK2结构与功能的研究。方法 :通过反转录 PCR从 NIH3T3小鼠成纤维细胞中获得小鼠蛋白激酶 CK2 β亚基编码区 c DNA,PCR扩增酶为高保真 DNA聚合酶。将 N de I/ H ind 彻底双酶切 PCR产物定向连接到牛小肠碱性磷酸酶去 5′端磷酸的同样彻底 Nde I/ H ind 双酶切的表达载体 p T7- 7中 ,转化感受态大肠杆菌 DH5 α获得转化子 ,用 0 .8%琼脂糖凝胶电泳初步筛选转化子 ,将阳性克隆进行单和双酶切分析鉴定。随机挑选两个阳性克隆进行 DNA测序。结果 :转化子的阳性筛选率为 10 0 % ,限制性酶切分析结果表明插入片段和重组质粒的大小与理论推测值相符。 DNA测序结果表明 :两个重组小鼠 CK2 β亚基克隆中的插入片段序列均与两种已报道的小鼠 CK2 β亚基 c DNA编码区序列分别存在一个碱基差异 ,但我们报道的这 2个差异碱基与大鼠、兔、猪和人 CK2 β亚基 c DNA的编码区相应碱基序列一致。结论 :本实验克隆的小鼠蛋白激酶 CK2 β亚基 c
基金Project supported by the National Key R&D Program of China(Grant No.2018YFA0305700)the National Natural Science Foundation of China(Grant Nos.11834016,11874400,and 11921004)+4 种基金the Beijing Natural Science Foundation,China(Grant No.Z190008)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(Grant No.QYZDB-SSW-SLH013)the CAS Interdisciplinary Innovation Teamsupport of Grant No.NSF-DMR-1350002support of NSF DMR Grant No.1729588。
文摘The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000℃ and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K.We found that Dy2Pt2O7 does not form long-range magnetic order,but displays characteristics of canonical spin ice such as Dy2Pt2O7,including(1)a large effective moment 9.64μB close to the theoretical value and a small positive Curie-Weiss temperatureθCW=+0.77 K signaling a dominant ferromagnetic interaction among the Ising spins;(2)a saturation moment ~4.5μB being half of the total moment due to the local<111>Ising anisotropy;(3)thermally activated spin relaxation behaviors in the low(~1 K)and high(~20 K)temperature regions with different energy barriers and characteristic relaxation time;and most importantly,(4)the presence of a residual entropy close to Pauling’s estimation for water ice.
文摘A new type of philosophy and mathematics from the pansystems view is introduced here, including the 7 philosophy theories (7PT) and related mathematizing researches. Many second/third philosophies are developed within pansystems framework and related applications to APT MS.
文摘A new type of philosophy and mathematics from the pansytems view is introduced here,including the 7 philosophic theories(7PT)and related mathematic researches.Many second/third philosophies are developed within pansvstems framework and related applications to APTMS.
文摘A new type of philosophy from the view of pansystems is introducedhere,including the 7 philosophy theories(7PT),fuzziness research andmany second/third philosophies are developed within pansystems frame-work.
基金funded by a PFR 2023 research grant from the Ministry of Education,Culture,Research,and Technology of the Republic of Indonesia(contract number 183/E5/PG/02.00.PL/2023).
文摘Numerous researchers in the energy field are engaged in a competitive race to advance hydrogen as a clean and environmentally friendly fuel.Studies have been conducted on the different aspects of hydrogen,including its production,storage,transportation and utilization.The catalytic methane decomposition technique for hydrogen production is an environmentally friendly process that avoids generating carbon dioxide gas,which contributes to the greenhouse effect.Catalysts play a crucial role in facilitating rapid,cost-effective and efficient production of hydrogen using this technique.In this study,reactive molecular dynamics simulations were employed to examine the impact of Pt7 cluster decoration on the surface of a Ni(110)catalyst,referred to as Pt7-Ni(110),on the rates of methane dissociation and molecular hydrogen production.The reactive force field was employed to model the atomic interactions that enabled the formation and dissociation of chemical bonds.Our reactive molecular dynamics simulations using the Pt7-Ni(110)catalyst revealed a notable decrease in the number of methane molecules,specifically~11.89 molecules per picosecond.The rate was approximately four times higher than that of the simulation system utilizing a Ni(110)catalyst and approximately six times higher than that of the pure methane,no-catalyst system.The number of hydrogen molecules generated during a simulation period of 150000 fs was greater on the Pt7-Ni(110)surface than in both the Ni(110)and pure methane systems.This was due to the presence of numerous dissociated hydrogen atoms on the Pt7-Ni(110)surface.
