CO2 Adsorption on the B12N12 Nanocage Encapsulated with Alkali Metals: A Density Functional Study

Haiyan Zhu,Qiyan Zhang,Qinfu Zhao,He Zhao,Yifan Feng,Bingbing Suo,Huixian Han,Qi Song,Yawei Li,Wenli Zou,Haiyan Zhu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.3

Density functional theory (DFT) calculations have been carried out to study the capacity of the B12N12 nanocage encapsulated with alkali metals (Li, Na, K) for the CO2 adsorption and activation. It is found that after encapsulating alkali metals, the alkali metal atoms are closer to one side of clusters instead of exactly lying at the center, and a considerable charge transfers from the inner alkali metal atoms to the B12N12 cage. Besides, the HOMO–LUMO gap (HLG) values of Li@B12N12, Na@B12N12 and K@B12N12 are decreased to about 6 eV, being much smaller than that of the pristine B12N12. Although the geometry structure parameters and the energy differences of M06-2X are slightly different from the ones of ωB97X-D, some identical results of two kinds of functional can be obtained. CO2 can be adsorbed chemically and physically on majority bonds of all the clusters, except for some bonds with large change in bond length and bond indices. The encapsulation of alkali-metal atoms may enhance the physical and chemical adsorption of CO2 on the surface of the clusters, in which Na@B12N12 and K@B12N12 are the most powerful physical and chemical adsorbent for CO2, respectively.

Tanshinone IIA Protects Endothelial Cells from H₂O₂-Induced Injuries via PXR Activation

( Haiyan Zhu ),( Zhiwu Chen ),( Zengchun Ma ),( Hongling Tan ),( Chengrong Xiao ),( Xianglin Tang ),( Boli Zhang ),( Yuguang Wang ),( Yue Gao ) 한국응용약물학회 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.6

Tanshinone IIA (Tan IIA) is a pharmacologically active substance extracted from the rhizome of Salvia miltiorrhiza Bunge (also known as the Chinese herb Danshen), and is widely used to treat atherosclerosis. The pregnane X receptor (PXR) is a nuclear receptor that is a key regulator of xenobiotic and endobiotic detoxification. Tan IIA is an efficacious PXR agonist that has a potential protective effect on endothelial injuries induced by xenobiotics and endobiotics via PXR activation. Previously numerous studies have demonstrated the possible effects of Tan IIA on human umbilical vein endothelial cells, but the further mechanism for its exerts the protective effect is not well established. To study the protective effects of Tan IIA against hydrogen peroxide (H₂O₂) in human umbilical vein endothelial cells (HUVECs), we pretreated cells with or without different concentrations of Tan IIA for 24 h, then exposed the cells to 400 μM H₂O₂ for another 3 h. Therefore, our data strongly suggests that Tan IIA may lead to increased regeneration of glutathione (GSH) from the glutathione disulfide (GSSG) produced during the GSH peroxidase-catalyzed decomposition of H₂O₂ in HUVECs, and the PXR plays a significant role in this process. Tan IIA may also exert protective effects against H₂O₂-induced apoptosis through the mitochondrial apoptosis pathway associated with the participation of PXR. Tan IIA protected HUVECs from inflammatory mediators triggered by H₂O₂ via PXR activation. In conclusion, Tan IIA protected HUVECs against H₂O₂-induced cell injury through PXR-dependent mechanisms.

Erratum to Tanshinone IIA Protects Endothelial Cells from H₂O₂-Induced Injuries via PXR Activation [Biomol Ther 25(6), 599-608 (2017)]

( Haiyan Zhu ),( Zhiwu Chen ),( Zengchun Ma ),( Hongling Tan ),( Chengrong Xiao ),( Xianglin Tang ),( Boli Zhang ),( Yuguang Wang ),( Yue Gao ) 한국응용약물학회 2024 Biomolecules & Therapeutics(구 응용약물학회지) Vol.32 No.2

Tanshinone IIA Protects Endothelial Cells from H₂O₂-Induced Injuries via PXR Activation

Zhu, Haiyan,Chen, Zhiwu,Ma, Zengchun,Tan, Hongling,Xiao, Chengrong,Tang, Xianglin,Zhang, Boli,Wang, Yuguang,Gao, Yue The Korean Society of Applied Pharmacology 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.6

Tanshinone IIA (Tan IIA) is a pharmacologically active substance extracted from the rhizome of Salvia miltiorrhiza Bunge (also known as the Chinese herb Danshen), and is widely used to treat atherosclerosis. The pregnane X receptor (PXR) is a nuclear receptor that is a key regulator of xenobiotic and endobiotic detoxification. Tan IIA is an efficacious PXR agonist that has a potential protective effect on endothelial injuries induced by xenobiotics and endobiotics via PXR activation. Previously numerous studies have demonstrated the possible effects of Tan IIA on human umbilical vein endothelial cells, but the further mechanism for its exerts the protective effect is not well established. To study the protective effects of Tan IIA against hydrogen peroxide ($H_2O_2$) in human umbilical vein endothelial cells (HUVECs), we pretreated cells with or without different concentrations of Tan IIA for 24 h, then exposed the cells to $400{\mu}M$ $H_2O_2$ for another 3 h. Therefore, our data strongly suggests that Tan IIA may lead to increased regeneration of glutathione (GSH) from the glutathione disulfide (GSSG) produced during the GSH peroxidase-catalyzed decomposition of $H_2O_2$ in HUVECs, and the PXR plays a significant role in this process. Tan IIA may also exert protective effects against $H_2O_2$-induced apoptosis through the mitochondrial apoptosis pathway associated with the participation of PXR. Tan IIA protected HUVECs from inflammatory mediators triggered by $H_2O_2$ via PXR activation. In conclusion, Tan IIA protected HUVECs against $H_2O_2$-induced cell injury through PXR-dependent mechanisms.

Tanshinone IIA Protects Endothelial Cells from H2O2-Induced Injuries via PXR Activation

Haiyan Zhu,Zhiwu Chen,Zengchun Ma,Hongling Tan,Chengrong Xiao,Xianglin Tang,Boli Zhang,Yuguang Wang,Yue Gao 한국응용약물학회 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.6

Tanshinone IIA (Tan IIA) is a pharmacologically active substance extracted from the rhizome of Salvia miltiorrhiza Bunge (also known as the Chinese herb Danshen), and is widely used to treat atherosclerosis. The pregnane X receptor (PXR) is a nuclear receptor that is a key regulator of xenobiotic and endobiotic detoxification. Tan IIA is an efficacious PXR agonist that has a potential protective effect on endothelial injuries induced by xenobiotics and endobiotics via PXR activation. Previously numerous studies have demonstrated the possible effects of Tan IIA on human umbilical vein endothelial cells, but the further mechanism for its exerts the protective effect is not well established. To study the protective effects of Tan IIA against hydrogen peroxide (H2O2) in human umbilical vein endothelial cells (HUVECs), we pretreated cells with or without different concentrations of Tan IIA for 24 h, then exposed the cells to 400 μM H2O2 for another 3 h. Therefore, our data strongly suggests that Tan IIA may lead to increased regeneration of glutathione (GSH) from the glutathione disulfide (GSSG) produced during the GSH peroxidase-catalyzed decomposition of H2O2 in HUVECs, and the PXR plays a significant role in this process. Tan IIA may also exert protective effects against H2O2-induced apoptosis through the mitochondrial apoptosis pathway associated with the participation of PXR. Tan IIA protected HUVECs from inflammatory mediators triggered by H2O2 via PXR activation. In conclusion, Tan IIA protected HUVECs against H2O2-induced cell injury through PXR-dependent mechanisms.

Stress field interference of hydraulic fractures in layered formation

Zhu, Haiyan,Zhang, Xudong,Guo, Jianchun,Xu, Yaqin,Chen, Li,Yuan, Shuhang,Wang, Yonghui,Huang, Jingya Techno-Press 2015 Geomechanics & engineering Vol.9 No.5

Single treatment and staged treatments in vertical wells are widely applied in sandstone and mudstone thin interbedded (SMTI) reservoir to stimulate the reservoir. The keys and difficulties of stimulating this category of formations are to avoid hydraulic fracture propagating through the interface between shale and sand as well as control the fracture height. In this paper, the cohesive zone method was utilized to build the 3-dimensional fracture dynamic propagation model in shale and sand interbedded formation based on the cohesive damage element. Staged treatments and single treatment were simulated by single fracture propagation model and double fractures propagation model respectively. Study on the changes of fracture vicinity stress field during propagation is to compare and analyze the parameters which influence the interfacial induced stresses between two different fracturing methods. As a result, we can prejudge how difficult it is that the fracture propagates along its height direction. The induced stress increases as the pumping rate increasing and it changes as a parabolic function of the fluid viscosity. The optimized pump rate is $4.8m^3/min$ and fluid viscosity is $0.1Pa{\cdot}s$ to avoid the over extending of hydraulic fracture in height direction. The simulation outcomes were applied in the field to optimize the treatment parameters and the staged treatments was suggested to get a better production than single treatment.

Hydraulic fracture initiation pressure of anisotropic shale gas reservoirs

Zhu, Haiyan,Guo, Jianchun,Zhao, Xing,Lu, Qianli,Luo, Bo,Feng, Yong-Cun Techno-Press 2014 Geomechanics & engineering Vol.7 No.4

Shale gas formations exhibit strong mechanical and strength anisotropies. Thus, it is necessary to study the effect of anisotropy on the hydraulic fracture initiation pressure. The calculation model for the in-situ stress of the bedding formation is improved according to the effective stress theory. An analytical model of the stresses around wellbore in shale gas reservoirs, in consideration of stratum dip direction, dip angle, and in-situ stress azimuth, has been built. Besides, this work established a calculation model for the stress around the perforation holes. In combination with the tensile failure criterion, a prediction model for the hydraulic fracture initiation pressure in the shale gas reservoirs is put forward. The error between the prediction result and the measured value for the shale gas reservoir in the southern Sichuan Province is only 3.5%. Specifically, effects of factors including elasticity modulus, Poisson's ratio, in-situ stress ratio, tensile strength, perforation angle (the angle between perforation direction and the maximum principal stress) of anisotropic formations on hydraulic fracture initiation pressure have been investigated. The perforation angle has the largest effect on the fracture initiation pressure, followed by the in-situ stress ratio, ratio of tensile strength to pore pressure, and the anisotropy ratio of elasticity moduli as the last. The effect of the anisotropy ratio of the Poisson's ratio on the fracture initiation pressure can be ignored. This study provides a reference for the hydraulic fracturing design in shale gas wells.

Performance of BMSC column with large eccentricity under natural exposure conditions

Haiyan Ma,Xiangchao ZENG,Hongfa Yu,Peng Yue,Haiwei Zhu,Chengyou Wu 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.4

As a new type of concrete material, basic magnesium sulfate cement concrete (BMSC) has the advantages, such as early strength, high strength, good toughness and crack resistance. However, it is unclear about the degradation of the mechanical properties of BMSC columns, which is exposed to the natural environment for several years. In order to apply this new concrete to practical engineering, six large-eccentricity compressive columns of BMSC were studied. The mechanical properties such as the crack propagation, failure morphology, lateral displacement and bearing capacity of BMSC column were studied. The results show that the degradation rate of ultimate load of BMSC column is from 6% to 7%. The degradation rate of the stiffness of the column is from 6% to 13%. With the increase of compressive strength of BMSC, the axial displacement and lateral displacement are gradually reduced. The calculation model of bearing capacity of the BMSC column under the large eccentric compression is proposed. This paper provides a reference for the application of BMSC columns in the civil engineering.

Electrochemical properties of stacked-nanoflake Li4Ti5O12 spinel synthesized by a polymer-pyrolysis method

Xiaoming Zhu,Xiaoyu Jiang,Haiyan Lu,Xinping Ai,Hanxi Yang,Yuliang Cao 한국물리학회 2014 Current Applied Physics Vol.14 No.4

Stacked-nanoflake Li4Ti5O12 spinel was synthesized via the pyrolysis of a LieTi copolymeric precursor formed by in situ polymerization of LiOH and [Ti(OC4H9)4] and acrylic acid. XRD and SEM characterization shows that the powders calcined at 700 C for 3 h was well-crystallized particles with submicron diameter. Chargeedischarge measurement showed the Li4Ti5O12 electrode had displayed excellent rate capability and delivered reversible capacity of 171, 158, 148, 138 and 99 mAh g1 at rates of 0.1C, 0.5C, 1C, 2C and 4C, respectively. The test electrode also showed excellent cyclability as the capacity retains 96.1% after 60 cycles between 0.5 and 2.5 V.

SIRT3-Mediated Dimerization of IDH2 Directs Cancer Cell Metabolism and Tumor Growth

Zou, Xianghui,Zhu, Yueming,Park, Seong-Hoon,Liu, Guoxiang,O'Brien, Joseph,Jiang, Haiyan,Gius, David American Association for Cancer Research 2017 Cancer research Vol.77 No.15

<P>These findings identify SIRT3 as a potential tumor suppressor, mediating its effects by limiting the ability of IDH2 to drive cancer cell metabolism and malignant progression.</P><P>The isocitrate dehydrogenase IDH2 produces α-ketoglutarate by oxidizing isocitrate, linking glucose metabolism to oxidative phosphorylation. In this study, we report that loss of SIRT3 increases acetylation of IDH2 at lysine 413 (IDH2-K413-Ac), thereby decreasing its enzymatic activity by reducing IDH2 dimer formation. Expressing a genetic acetylation mimetic IDH2 mutant (IDH2<SUP>K413Q</SUP>) in cancer cells decreased IDH2 dimerization and enzymatic activity and increased cellular reactive oxygen species and glycolysis, suggesting a shift in mitochondrial metabolism. Concurrently, overexpression of IDH2<SUP>K413Q</SUP> promoted cell transformation and tumorigenesis in nude mice, resulting in a tumor-permissive phenotype. IHC staining showed that IDH2 acetylation was elevated in high-risk luminal B patients relative to low-risk luminal A patients. Overall, these results suggest a potential relationship between SIRT3 enzymatic activity, IDH2-K413 acetylation-determined dimerization, and a cancer-permissive phenotype. <I>Cancer Res; 77(15); 3990–9. ©2017 AACR</I>.</P>