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柴胡皂苷D诱导内质网应激增强胶质瘤细胞替莫唑胺敏感性的机制

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中国药理学通报 2024年第6期40卷 1105-1114页

作者：刘桂梅郑蕊刘晓斌刘永仙王亚萍张玉富张静靳小燕刘雨思延安大学基础医学院陕西延安716000 延安大学附属医院肝胆外科陕西延安716000

目的探讨柴胡皂苷D(saikosaponin D,SSD)联合替莫唑胺(temozolomide,TMZ)对神经胶质瘤细胞(glioblastoma,GBM)的协同增敏作用及分子机制。方法CCK-8法结合HE染色分析RG-2、U251、LN-4283种GBM细胞系对SSD、TMZ敏感性差异并筛选最佳配伍浓度。通过克隆形成实验、HE染色结合Hoechst荧光染色检测联合给药对GBM细胞增殖影响。单丹磺酰胺(monodansylcadaverine,MDC)染色观察GBM细胞自噬小体形成。Western blot结合ICC法检测内质网应激相关因子及凋亡、自噬蛋白表达与分布变化。结果GBM细胞对TMZ敏感性顺序为RG-2>U251>LN-428。SSD联合TMZ给药结果显示出对GBM细胞系增殖的协同抑制作用,并经细胞克隆形成实验证实。与TMZ组相比,Hoechst荧光染色显示联合给药组细胞核亮染数目明显增加。MDC荧光染色发现SSD/TMZ组胞质出现致密浓染绿色颗粒,且较TMZ组相比明显增多。Western blot结果显示,较TMZ组相比,SSD/TMZ组内质网应激标志蛋白GRP78、CHOP、p-PERK、ATF6表达增高(P<0.05);凋亡蛋白caspase-12、caspase-9、caspase-3、cleaved caspase-3、Bax及自噬蛋白LC3、Beclin-1表达均明显增高(P<0.05)并经ICC实验验证。结论SSD可协同TMZ抑制GBM细胞增殖且诱导其发生凋亡与自噬,通过激活内质网应激途径提高GBM细胞对TMZ化疗敏感性。

关键词：柴胡皂苷D 替莫唑胺神经胶质瘤增殖凋亡自噬内质网应激

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高压液氨预热器管板环焊缝主副加热局部热处理

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化工机械 2024年第3期51卷 340-347页

作者：陈晶徐成张峥苏厚德张玉福上海蓝滨石化设备有限责任公司甘肃蓝科石化高新装备股份有限公司

管板环焊缝局部热处理是影响高压液氨预热器服役安全的关键制造技术,传统局部热处理时温度分布不均匀、管板约束大,导致残余应力难以消除。对此,采用主副加热局部热处理方法,并验证该方法在高压液氨预热器局部热处理时的有效性。计算与... 详细信息

管板环焊缝局部热处理是影响高压液氨预热器服役安全的关键制造技术,传统局部热处理时温度分布不均匀、管板约束大,导致残余应力难以消除。对此,采用主副加热局部热处理方法,并验证该方法在高压液氨预热器局部热处理时的有效性。计算与测试结果表明,传统局部热处理仅可降低外表面的轴向和环向残余应力,而内表面轴向应力会略微增大,环向应力降幅较小;主副加热局部热处理使内表面轴向应力由283 MPa降低至100 MPa以下,降幅约64%,环向应力由324 MPa降低至206 MPa,降幅约37%,显著降低了设备内表面应力腐蚀开裂的敏感性。

关键词：高压液氨预热器局部热处理管板环缝残余应力

New speckle pattern interferometry for precise in situ deformation measurements

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Chinese Optics Letters 2024年第1期22卷 34-40页

作者：章如月 yu fu 缪泓 CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China Shenzhen Key Laboratory of Intelligent Optical Measurement and Detection College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

A new electronic speckle pattern interferometry method is proposed to realize in situ deformation *** feature of the method is the combination of a high-speed camera and multiple laser Doppler vibrometers(LDVs)for synchronous *** high-speed camera is used to record and select effective interferograms,while the LDVs are used to measure the rigid body displacement caused by vibrations.A series of effective interferograms with known shifted phase values are obtained to calculate the deformation *** experimental results show that the method performs well in measuring static and dynamic deformations with high accuracy in vibrating environments.

关键词： speckle pattern interferometry laser Doppler vibrometers in situ deformation measurements

Special issue on electrochemical conversion and utilization of hydrogen energy

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Frontiers in Energy 2024年第3期18卷 263-264页

作者： yun ZHENG Bo yu Xiaogang fu Jiujun zhang Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China State Key Laboratory of Solidification Processing Atomic Control&Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

The concerns over energy crisis and climate change caused by the excessive consumption of fossil fuels and the associated emission of greenhouse gases, have driven many countries to develop policies for an energy transition into zero-carbon energy sources, essentially aiming at decarbonizing their energy systems. Among various renewable sources, hydrogen has been hailed as an ideal alternative to provide secure, cost-effective, and non-polluting energy. In recent years, there has been noteworthy progress in hydrogen electrochemical conversion and utilization techniques and devices, including water electrolyzers, proton-exchange membrane fuel cells (PEMFCs), solid oxide fuel cells (SOFCs), etc. Each of these technologies has yielded a series of encouraging advances. To showcase these recent advances, Frontiers in Energy is launching a special issue titled “electrochemical conversion and utilization of hydrogen energy”.

关键词： hydrogen energy. electrochemical

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan Qing-tao Guo Kai-lun zhang fu-zhi yu yu-ying Li yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Effect of Al content in molten steel on interaction between MgO-C refractory and SPHC steel

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Journal of Iron and Steel Research(International) 2024年第4期31卷 838-848页

作者： fu-bin Gao fu-ming Wang Xiang zhang Tian-yu Du Xin-hua Wangg School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Handan Iron and Steel Company Hegang GroupHandan 056015HebeiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The effect of Al content in molten steel on the interaction between SPHC steel(0.005-0.068 wt.%Al,and 19×10^(-4)-58×10^(-4)wt.%O)and MgO-C refractory(11.63 wt.%C)was ***-metallic inclusions in the steel were examined at various periods(0,5,15,30,45,and 60 min)as well as the MgO-C interface after 60 min of corrosion at 1600℃.The results show that when MgO-C refractory comes into contact with SPHC steel,the refractory interface consists of three layers arranged from the innermost to the outermost,including the original refractory layer,the dense MgO layer,and the iron infiltration *** carbon in the MgO-C refractories and the Al content in the molten steel undergo a reaction with the MgO in the refractories,resulting in an increase in Mg concentration in the *** Al content in the molten steel from 0.005 to 0.068 wt.%causes a spinel layer to appear at the interface,and the disappearance time of Al_(2)O_(3) inclusions in the steel decreases from 60 to 30 min,while the average MgO content in inclusions ***,controlling the Al content in the molten steel and the smelting duration can help regulate the formation of spinel inclusionsinthe steel.

关键词： MgO-C refractory SPHC steel Inclusion-Spinel Al-killed steel Interfacial reaction

Controlling of coordination state of Ru_(x)N_(y) clusters for efficient oxygen reduction electrocatalysis

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Nano Research 2024年第3期17卷 1035-1041页

作者： Weiyang fu Yihuan yu Tongtong Liu Yinliang Cao Zhengping zhang Feng Wang State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Zhejiang Tianneng Hydrogen Energy Technology Co. Ltd.Huzhou 313100China

Ruthenium(Ru)is an attractive potential alternative to platinum as an electrocatalyst for the oxygen reduction reaction(ORR),in virtue of its high catalytic selectivity and relatively low *** this work,a series of well-dispersed nitrogen-coordinated Ru-clusters on carbon black(Ru_(x)N_(y)/C)were prepared by pyrolyzing different Ru-containing sandwich compounds as the Ru *** higher thermal stability of these complexed sandwich precursors(bis(1,2,3,4,5-pentamethylcyclopentadienyl)Ru(II)monomer,dichloro(p-cymene)Ru(II)dimer,and chloro(1,2,3,4,5-pentamethylcyclopentadienyl)Ru(II)tetramer)affords the control of coordinated state for the resulting Ru-clusters,in comparison of that derived from ruthenium *** the pyrolysis treatment,the Ru coordinated state in Ru_(x)N_(y)/C,with the Ru–N and Ru–Ru bonds,still showed the structural inheritance from the Ru(II)monomer,dimer,and tetramer,but using ruthenium chlorides as the Ru source resulted in the nanoscale Ru *** ORR testing exhibited that the Ru_(x)N_(y)/C sample derived from the Ru(II)tetramer(Ru_(x)N_(y)/C-T)presents the higher catalytic activity than the other obtained samples in either alkaline or acidic *** in the acidic electrolyte,Ru_(x)N_(y)/C-T shows the comparable ORR activity to that of Pt/C catalysts,and it shows the superior tolerance against methanol and *** X-ray absorption spectroscopy and density functional theory calculations demonstrate that these tetra-nuclear Ru-clusters could be the most active site due to their broadened d-orbital bands and lower energy d-band center than those of other subnano species and nanocrystals,and their favorable Yeager-type adsorption of O_(2)-molecules is also contributed to promoting O–O bond cleavage and accelerating the ORR process.

关键词： ruthenium clusters coordination environment sandwich compounds electrocatalysis oxygen reduction reaction

Response of ocean acidification to atmospheric carbon dioxide removal

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Journal of Environmental Sciences 2024年第6期140卷 79-90页

作者： Jiu Jiang Long Cao Xiaoyu Jin Zechen yu Han zhang Jianjie fu Guibin Jiang School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Geoscience Big Data and Deep Resources of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310058China Zhejiang Climate Center Hangzhou 310052China

Artificial CO_(2)removal from the atmosphere(also referred to as negative CO_(2)emissions)has been proposed as a potential means to counteract anthropogenic climate *** we use an Earth system model to examine the response of ocean acidification to idealized atmospheric CO_(2)removal *** our simulations,atmospheric CO_(2)is assumed to increase at a rate of 1%per year to four times its pre-industrial value and then decreases to the pre-industrial level at a rate of 0.5%,1%,2%per year,*** results show that the annual mean state of surface ocean carbonate chemistry fields including hydrogen ion concentration([H^(+)]),pH and aragonite saturation state respond quickly to removal of atmospheric CO_(2).However,the change of seasonal cycle in carbonate chemistry lags behind the decline in atmospheric CO_(2).When CO_(2)returns to the pre-industrial level,over some parts of the ocean,relative to the pre-industrial state,the seasonal amplitude of carbonate chemistry fields is substantially *** results also show that changes in deep ocean carbonate chemistry substantially lag behind atmospheric CO_(2)*** CO_(2)returns to its pre-industrial value,the whole-ocean acidity measured by[H^(+)]is 15%-18%larger than the pre-industrial level,depending on the rate of CO_(2)*** study demonstrates that even if atmospheric CO_(2)can be lowered in the future as a result of net negative CO_(2)emissions,the recovery of some aspects of ocean acidification would take decades to centuries,which would have important implications for the resilience of marine ecosystems.

关键词： Carbon dioxide removal Net negative CO_(2)emission Ocean acidification Climate change Earth system modeling

Elastohydrodynamic Lubrication Interface Stiffness and Damping Considering Asperity Lateral Contact

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Acta Mechanica Solida Sinica 2024年第1期37卷 109-123页

作者： Zhiqiang Gao yu zhang Xian Wei Yanfang Zhu Lixia Peng Weiping fu Wen Wang School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China School of Intelligent Manufacturing Panzhihua UniversityPanzhihua 617000China Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Light Chemical TechnologyYibin 644002China School of Mechanical Engineering Anyang Institute of TechnologyAnyang 455099China

Elastohydrodynamic lubrication(EHL)point contact occurs between two rough surfaces at the mesoscopic level,while the interaction of rough surfaces involves contact between asperities at the microscale *** most cases,the contact between asperities within an interface takes the form of lateral contact rather than peak *** devoid of contact asperities are filled with lubricating ***,conventional models often oversimplify lateral contact forms as interactions between asperities and a smooth,rigid *** simplifications fail to accurately represent the true contact conditions and can lead to inaccuracies in the analysis of EHL’s contact *** address this issue,we have developed a novel EHL interface model comprising two rough *** model allows us to explore the influence of asperity height,contact angle,and contact azimuth angle on EHL interface performance.

关键词： EHL interface Asperity lateral contact Contact stiffness Damping