地球极尖区是太阳风等离子体进入内磁层和电离层的一个重要“窗口”,但其总体结构长期以来尚未确定.2008年3月8日两个连续亚暴期间,太阳风的整体变化范围较大,基于全球三维数值模拟我们建立了一个由行星际磁场(interplanetary magnetic ...地球极尖区是太阳风等离子体进入内磁层和电离层的一个重要“窗口”,但其总体结构长期以来尚未确定.2008年3月8日两个连续亚暴期间,太阳风的整体变化范围较大,基于全球三维数值模拟我们建立了一个由行星际磁场(interplanetary magnetic field,IMF)B_(Y)、B_(Z)控制的低高度(1.1个地球半径高度)极尖区的预报模式.该模式由椭圆函数构造而成,拟合函数由极尖区位置和宽度控制并取决于IMF B_(Y)和B_(Z).极尖区地磁纬度(geomagnetic latitude,MLAT)随着向北IMF B_(Z)的增加而增加,随着向南IMF B_(Z)的增加而明显降低.当B_(Y)=0时,磁地方时(magnetic local time,MLT)接近12,当IMF为东向(西向)时,极尖区中心将位于北半球下午(上午)侧.MLAT宽度随IMF B_(Z)从北转南而减小,MLT宽度随IMF B_(Z)从北转南而增大.通过与DMSP卫星观测结果的比较分析,验证了该模型的有效性.基于低高度极尖区预报模式,将进一步建立极尖区三维预报模式,这将有助于空间天气预报.展开更多
利用全球磁流体模拟的结果,本文研究了行星际磁场By对弓激波位型的影响.结果显示:随着行星际磁场By绝对值的增大,弓激波的日下点距离、旋转对称张角、南北非对称性以及旋转非对称性均随之增加.其中,By对弓激波日下点距离的影响可达5 R ...利用全球磁流体模拟的结果,本文研究了行星际磁场By对弓激波位型的影响.结果显示:随着行星际磁场By绝对值的增大,弓激波的日下点距离、旋转对称张角、南北非对称性以及旋转非对称性均随之增加.其中,By对弓激波日下点距离的影响可达5 R E左右.东向By和西向By对弓激波位型影响具有对称性,东向By和西向By大小相同时弓激波日下点距离、旋转对称张角以及旋转非对称性参数均相同,而南北非对称性参数大小相同正负相反.行星际磁场By占主导时弓激波尾部横截面在南北方向上拉伸,并且拉伸程度随着By绝对值的增大而增大,弓激波尾部横截面的拉伸现象与磁声波马赫数密切相关.展开更多
OBJECTIVE:To investigate the action and underlying mechanisms of Huoxue Jiedu Huayu recipe(活血解毒化瘀方,HJHR)against unilateral ureteral obstruction(UUO)-induced injury in the contralateral kidney.METHODS:Forty-eigh...OBJECTIVE:To investigate the action and underlying mechanisms of Huoxue Jiedu Huayu recipe(活血解毒化瘀方,HJHR)against unilateral ureteral obstruction(UUO)-induced injury in the contralateral kidney.METHODS:Forty-eight male Sprague-Dawley rats weighing(200±10)g were used in this study and randomly assigned to 4 groups:a sham group,a UUO group,a UUO+eplerenone(EPL)group,and a UUO+HJHR group.The contralateral kidneys were harvested for further study 180 d after surgery.Histological analysis,immunohistochemistry and immunofluorescence were used to study the fibrosis of the contralateral kidneys obtained from UUO rats.Contralateral kidney damagerelated pathway proteins were detected by real-time polymerase chain reaction and Western blot analysis.RESULTS:HJHR significantly inhibited fibrosis of the contralateral kidney in UUO rats by attenuating the UUOinduced macrophage-to-myofibroblast transition(MMT)in the contralateral kidney.Moreover,HJHR attenuated fibrosis in the contralateral kidney of UUO rats by preventing MMT through the aldosterone/mineralocorticoid receptor/serum/glucocorticoid regulated kinase 1 pathway.CONCLUSIONS:Our findings suggest that HJHR may be a potential treatment for renal interstitial fibrosis of obstructive nephropathy.展开更多
The subsolar magnetopause is the boundary between the solar wind and the Earth's magnetosphere,where reduced solar wind dynamic pressure is equal to the magnetic pressure of the Earth's outer magnetosphere.We ...The subsolar magnetopause is the boundary between the solar wind and the Earth's magnetosphere,where reduced solar wind dynamic pressure is equal to the magnetic pressure of the Earth's outer magnetosphere.We use a global magnetohydrodynamic (MHD)model to estimate the ratio f of the compressed magnetic field just inside the subsolar magnetopause to the purely dipolar magnetic field.We also compare our numerical results to a similar work by Shue,which used Time History of Events and Macroscale Interactions during Substorms(THEMIS)data.Our results show that the ratio f is linearly proportional to the subsolar magnetopause standoff distance(r0)for both the northward and southward interplanetary magnetic field,properties consistent with Shue but with a smaller proportionality constant.However,previous theoretical studies show that f is nearly independent of the subsolar standoff distance.The global model results also show that f is smaller for the southward Interplanetary Magnetic Field(IMF)under the same r0,and that the proportionality constant for the southward IMF is larger than that for the northward IMF.Both conclusions agree with statistical results from observations by Shue.展开更多
Using the global magnetohydrodynamics(MHD) simulation model, we investigated the effects of the interplanetary magnetic field(IMF) clock angle on the shape of bow shock, including its rotational asymmetry and subsolar...Using the global magnetohydrodynamics(MHD) simulation model, we investigated the effects of the interplanetary magnetic field(IMF) clock angle on the shape of bow shock, including its rotational asymmetry and subsolar point. For general northward IMF( z component Bz > 0), the rotational symmetry of the bow shock is broken by the effects of fast magnetosonic Mach number(Mms), and the cross-sectional line of the bow shock is an ellipse with the semi-major axis along the direction perpendicular to the IMF. The ratio or D-value between semi-major and semi-minor axis can be used to illustrate the extent of asymmetry of the bow shock. On the basis of the multiple parameters fitting, we obtain the changing relationship of both semi-axes with the clock angle and the distance away from the Earth. For general southward IMF(Bz < 0), the cross sectional line of the bow shock is highly asymmetrical under the multiple effects of magnetopause and Mms. The effects of IMF clock angle on subsolar point depend mainly on the changing subsolar point of magnetopause as an obstacle. The distance of subsolar point of bow shock from the Earth increases with the increasing IMF clock angle for Bz > 0, and decreases with the increasing IMF clock angle for Bz < 0.展开更多
A triformylphloroglucinol-based AiB2-typed covalent organic polymer(TFG-BPTH)was successfully constructed by the condensation reaction of triformylphloroglucinol(TFG)and 2.5-bis(2-propynyloxy)terephthalo-hydrazide(BPT...A triformylphloroglucinol-based AiB2-typed covalent organic polymer(TFG-BPTH)was successfully constructed by the condensation reaction of triformylphloroglucinol(TFG)and 2.5-bis(2-propynyloxy)terephthalo-hydrazide(BPTH)under solvothermal conditions.The structure of the TFG-BPTH was confirmed by spectra tech-niques including FTIR and solid-state IC CP/MAS NMR spectroscopy.The mophological features of TFG-BPTH were analyzed using scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The TFG-BPTH possessed good thermal and chemical stability,and exhibited good photocatalytic activity as a metal-free heterogeneous catalyst for oxidation of amines to valuable imines under visible light irradiation using O2 as greer oxidant.In addition,the catalyst could be readily recovered from the reaction mixture by simple filtration and reused for at least five cycles without any observable change in structure and catalytic activity.展开更多
文摘利用全球磁流体模拟的结果,本文研究了行星际磁场By对弓激波位型的影响.结果显示:随着行星际磁场By绝对值的增大,弓激波的日下点距离、旋转对称张角、南北非对称性以及旋转非对称性均随之增加.其中,By对弓激波日下点距离的影响可达5 R E左右.东向By和西向By对弓激波位型影响具有对称性,东向By和西向By大小相同时弓激波日下点距离、旋转对称张角以及旋转非对称性参数均相同,而南北非对称性参数大小相同正负相反.行星际磁场By占主导时弓激波尾部横截面在南北方向上拉伸,并且拉伸程度随着By绝对值的增大而增大,弓激波尾部横截面的拉伸现象与磁声波马赫数密切相关.
基金Supported by Natural Science Foundation-funded Project:Effect of Macrophage-to-Myofibroblast Transition in Contralateral Kidney of Unilateral Ureteral Obstruction Rats Through the Aldosterone/MR/SGK1 Pathway and Inhibition of Chinese Herbs(No.81873251)Natural Science Foundation-funded Project:Aldosterone-induced Macrophage Polarization-lymphatic Endothelial Cell-like Transformation Involved in Renal Fibrosis and the Protective Effect of Yiqi Jiedu Huayu Herbs(No.82205006)Youth Top Talent Project of Hebei Provincial Department of Education:Mechanism of Renal Fibrosis Induced by NF-kB/IL-8 Induced MMT in UUO Rats(BJK2022004)。
文摘OBJECTIVE:To investigate the action and underlying mechanisms of Huoxue Jiedu Huayu recipe(活血解毒化瘀方,HJHR)against unilateral ureteral obstruction(UUO)-induced injury in the contralateral kidney.METHODS:Forty-eight male Sprague-Dawley rats weighing(200±10)g were used in this study and randomly assigned to 4 groups:a sham group,a UUO group,a UUO+eplerenone(EPL)group,and a UUO+HJHR group.The contralateral kidneys were harvested for further study 180 d after surgery.Histological analysis,immunohistochemistry and immunofluorescence were used to study the fibrosis of the contralateral kidneys obtained from UUO rats.Contralateral kidney damagerelated pathway proteins were detected by real-time polymerase chain reaction and Western blot analysis.RESULTS:HJHR significantly inhibited fibrosis of the contralateral kidney in UUO rats by attenuating the UUOinduced macrophage-to-myofibroblast transition(MMT)in the contralateral kidney.Moreover,HJHR attenuated fibrosis in the contralateral kidney of UUO rats by preventing MMT through the aldosterone/mineralocorticoid receptor/serum/glucocorticoid regulated kinase 1 pathway.CONCLUSIONS:Our findings suggest that HJHR may be a potential treatment for renal interstitial fibrosis of obstructive nephropathy.
基金supported by the National Natural Science Foundation of China(40874087 and 41031063)the China Meteorology Administration(GYHY201106011)the China Public Science and Technology Research Funds Projects of Ocean(201005017)
文摘The subsolar magnetopause is the boundary between the solar wind and the Earth's magnetosphere,where reduced solar wind dynamic pressure is equal to the magnetic pressure of the Earth's outer magnetosphere.We use a global magnetohydrodynamic (MHD)model to estimate the ratio f of the compressed magnetic field just inside the subsolar magnetopause to the purely dipolar magnetic field.We also compare our numerical results to a similar work by Shue,which used Time History of Events and Macroscale Interactions during Substorms(THEMIS)data.Our results show that the ratio f is linearly proportional to the subsolar magnetopause standoff distance(r0)for both the northward and southward interplanetary magnetic field,properties consistent with Shue but with a smaller proportionality constant.However,previous theoretical studies show that f is nearly independent of the subsolar standoff distance.The global model results also show that f is smaller for the southward Interplanetary Magnetic Field(IMF)under the same r0,and that the proportionality constant for the southward IMF is larger than that for the northward IMF.Both conclusions agree with statistical results from observations by Shue.
基金supported by the National Natural Science Foundation of China(Grant Nos.41231067,41374172)the National Basic Research Program of China(Grant No.2012CB825602)the Specialized Research Fund for State Key Laboratories of China
文摘Using the global magnetohydrodynamics(MHD) simulation model, we investigated the effects of the interplanetary magnetic field(IMF) clock angle on the shape of bow shock, including its rotational asymmetry and subsolar point. For general northward IMF( z component Bz > 0), the rotational symmetry of the bow shock is broken by the effects of fast magnetosonic Mach number(Mms), and the cross-sectional line of the bow shock is an ellipse with the semi-major axis along the direction perpendicular to the IMF. The ratio or D-value between semi-major and semi-minor axis can be used to illustrate the extent of asymmetry of the bow shock. On the basis of the multiple parameters fitting, we obtain the changing relationship of both semi-axes with the clock angle and the distance away from the Earth. For general southward IMF(Bz < 0), the cross sectional line of the bow shock is highly asymmetrical under the multiple effects of magnetopause and Mms. The effects of IMF clock angle on subsolar point depend mainly on the changing subsolar point of magnetopause as an obstacle. The distance of subsolar point of bow shock from the Earth increases with the increasing IMF clock angle for Bz > 0, and decreases with the increasing IMF clock angle for Bz < 0.
基金Supported by the National Natural Science Foundation of China(No.51703076).
文摘A triformylphloroglucinol-based AiB2-typed covalent organic polymer(TFG-BPTH)was successfully constructed by the condensation reaction of triformylphloroglucinol(TFG)and 2.5-bis(2-propynyloxy)terephthalo-hydrazide(BPTH)under solvothermal conditions.The structure of the TFG-BPTH was confirmed by spectra tech-niques including FTIR and solid-state IC CP/MAS NMR spectroscopy.The mophological features of TFG-BPTH were analyzed using scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The TFG-BPTH possessed good thermal and chemical stability,and exhibited good photocatalytic activity as a metal-free heterogeneous catalyst for oxidation of amines to valuable imines under visible light irradiation using O2 as greer oxidant.In addition,the catalyst could be readily recovered from the reaction mixture by simple filtration and reused for at least five cycles without any observable change in structure and catalytic activity.
