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Critical behavior and effect of Sr substitution in double perovskite Ca2CrSbO6

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Chinese Physics B 2021年第3期30卷 454-460页

作者： Yuan-Yuan Jiao jian-Ping sun qi Cui The State Key Laboratory of Refractories and Metallury Wuhan University of Science and TechnologyWuhan 430081China Faculty of Science Wuhan University of Science and TechnologyWuhan 430062China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The double perovskite Ca2CrSbO6 exhibits a ferromagnetic long-range order below Tc=13 K and a saturation magnetization of 2.35µB at 2 *** this study,the polycrystalline Ca2CrSbO6 is synthesized under high pressure and high temperature,and the critical behavior of the ferromagnetic material as well as the effects of the magnetic behavior due to the isovalent substitution of Sr2+for Ca2+is *** studied are the ferromagnetic criticality of the double perovskite Ca2CrSbO6 at the ferromagnetic transition temperature Tc≈12.6 K from the isotherms of magnetization M(H)via an iteration process and the Kouvel–Fisher *** critical exponents associated with the transition are determined as follows:β=0.322,γ=1.241,andδ=*** magnetization data in the vicinity of Tc can be scaled into two universal curves in the plot of M/|ε|βversus H/|ε|β+γ,whereε=T/Tc−*** obtainedβandγvalues are consistent with the predicted values from a three-dimensional Ising *** effects of Sr substitution on the double perovskite Ca2CrSbO6 are taken into *** the Sr content increases,the(Ca2−xSrx)CrSbO6 polycrystal shows a continuous switch from ferromagnetic to antiferromagnetic behavior.

关键词： high-temperature and high-pressure synthesis ferromagnet Ca2CrSbO6

影响牙髓干细胞成骨及成牙本质分化的相关物理因素及作用机制

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中国组织工程研究 2025年第7期29卷 1531-1540页

作者：孙玉婷吴家媛张剑遵义医科大学口腔医学院贵州省遵义市563000

背景:牙髓干细胞是口腔颌面部组织工程中极具应用潜力的干细胞之一,较骨髓间充质干细胞具有采集方便、伦理问题少以及增殖分化潜能高等优势。目前,除了生物化学等因素外,物理刺激对于牙髓干细胞的成骨/成牙本质分化也起着关键性的作用... 详细信息

背景:牙髓干细胞是口腔颌面部组织工程中极具应用潜力的干细胞之一,较骨髓间充质干细胞具有采集方便、伦理问题少以及增殖分化潜能高等优势。目前,除了生物化学等因素外,物理刺激对于牙髓干细胞的成骨/成牙本质分化也起着关键性的作用。目的:综述影响牙髓干细胞成骨/成牙本质分化的相关物理因素以及可能涉及的信号传导通路作用机制,寻找影响其分化的最佳诱导条件。方法:检索PubMed和中国知网数据库,以“牙髓干细胞,成骨分化,成牙本质分化,低氧,机械力,激光,磁场,微重力”为中文检索词,以“dental pulp stem cells(DPSCs),osteogenesis differentiation,odontoblastic differentiation,hypoxia,mechanical force,laser therapy,magnetic fields,microgravity”为英文检索词,选取与影响牙髓干细胞成骨/成牙本质分化相关物理因素有关的79篇文献进行综述。结果与结论:(1)微环境中直接或间接的物理信号在调控牙髓干细胞定向分化方面展现出了广阔的应用前景。低氧、力学刺激(动静水压力、机械牵张力及剪切力等)、激光、微重力和磁场等相关物理因素对牙髓干细胞的影响以促进成骨/成牙本质分化为主,因口颌系统拥有复杂的力学环境,力学刺激是细胞环境改变的关键物理因素,同时也是组织工程的一个前沿领域,深入探讨牙髓干细胞对力学环境的响应为口腔疾病的诊断及治疗提供新思路。(2)因该领域比较“年轻”,相关因素涉及的设备参数尚未统一,相关结果存在不一致性,未能达成共识,之后应进一步探索及优化相关物理因素的最佳诱导参数及作用条件。(3)支架材料作为组织工程的三要素之一,在牙髓干细胞成骨/成牙本质分化方面也起到了促进作用,同时也推动了材料学的发展及临床技术的进步。(4)其中涉及到的信号通路有Notch,Wnt,MAPK等,关于物理刺激如何调控牙髓干细胞行为的相关生物学基础尚未明确,未来将进一步探究其具体作用机制,为物理因素影响下的牙髓再生及骨组织工程提供新思路。

关键词：牙髓干细胞成骨分化成牙本质分化物理因素力学因素信号通路干细胞组织工程

毛细管气相色谱法同时测定工业废水中微量的萘、α-萘酚及蒽

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九江学院学报 2009年第6期28卷 45-48页

作者：孙剑奇刘小风钟婵娟万谦九江学院化学化工学院应用化学研究所江西九江332005

本文建立了同时测定工业废水中微量的萘、α-萘酚及蒽的毛细管气相色谱方法。以二氯乙烷和氯化钠的混合液萃取水样,利用毛细管柱气相色谱-FID进行检测,以外标法定量。该方法测定的萘、α-萘酚、蒽的标准工作曲线方程分别为y=23.091x＋0.... 详细信息

本文建立了同时测定工业废水中微量的萘、α-萘酚及蒽的毛细管气相色谱方法。以二氯乙烷和氯化钠的混合液萃取水样,利用毛细管柱气相色谱-FID进行检测,以外标法定量。该方法测定的萘、α-萘酚、蒽的标准工作曲线方程分别为y=23.091x＋0.688（r=0.9996）,y=17.788x-13.136（r=0.9992）,y=25.123x-10.756（r=0.9991）,检出限（S/N=3）分别是5.3×10-4μ***^-1,6.9×10-4μ***^-1,4.9×10-4μg.m^L-1,线性范围分别是1.8×10^-3 - 40μ***^-1、2.3×10^-3 - 60μ***^-1、1.6×10^-3 - 50μ***^-1。对此多环芳烃体系标准混合物溶液进行了3个不同水平的添加,每个水平重复6次进样,萘、α-萘酚、蒽的平均加标回收率分别为89%-104%、97%-113%、90%-106%,相对标准偏差分别为1.7%-2.6%、1.9%-3.7%、1.8%-3.5%。相同条件下,实际工业废水样品经富集后检测,萘,α-萘酚,蒽的平均浓度分别为196.7μ***^-1、20.65μ***^-1、100.8μ***^-1。实验结果表明：本方法操作简便、快速、准确、灵敏度高、线性范围较宽,测定结果令人满意。

关键词：毛细管柱气相色谱法多环芳烃萘 α-萘酚蒽工业废水

Advances on Seed Vigor Physiological and Genetic Mechanisms

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Agricultural Sciences in China 2007年第9期6卷 1060-1066页

作者： sun Qun WANG jian-hua sun Bao-qi Department of Seed Science College of Agriculture and Biotechnology China Agricultural University Beijing 100094 P.R.China

Seed vigor is a more promising seed quality character reflecting potential seed germination, field emergence and seed storage ability under different conditions than standard germination. Standard germination is influenced by genetic background and environmental effects during seed development and storage conditions. The latest research on physiological mechanism in seed vigor showed that at the late stage of seed development, the development of seed vigor involves some stress-resistant substances including late embryogenesis abundant （LEA） protein, oligosaccharides and abscisic acid （ABA）. Whereas the loss of seed vigor, or seed aging and deterioration, could be attributed to lipid peroxidation, chromosome deformation and genes aberrance, and embryo protein degradation, etc. Seed vigor is a quantitative character controlled by multi-genes. Genetic and quantitative trait locus （QTL） analyses on seed-vigor trait in model plants, such as Arabidopsis and rice, are mostly concentrated on related morphology traits, whereas few physiological traits have been researched. It was concluded that, all of the QTL genetic characteristics of seed vigorincluding QTL quantities, its locus on chromosome, genetic effects, and interaction effects between genetic and environment, differed with plant species and used seed-vigor traits.

关键词： seed vigor physiological and genetic mechanism QTL analyses

High activity in catalytic cracking of large molecules over micro-mesoporous silicoaluminophosphate with controlled morphology

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Science China Chemistry 2010年第11期53卷 2279-2284页

作者： qi jian ZHAO TianBo XU Xin LI FengYan sun GuiDa Institute for Chemical Physics Beijing Institute of TechnologyBeijing 100081China Department of Applied Chemistry Beijing Institute of Petrochemical TechnologyBeijing 102617China

A novel micro-mesoporous silicoaluminophosphate(MUS-5) with controlled morphology has been first synthesized in a two-step *** physical properties of the silicoaluminophosphate were characterized using XRD,SEM,TEM,nitrogen adsorption-desorption and NH3-TPD *** the pH value of the solution system was varied in the range from 2.0 to 5.0,three different morphologies of silicoaluminophosphate including chain-like,flower-like and barrel-like morphology were *** tests showed that the silicoaluminophosphate exhibited higher catalytic activity compared with the conventional microporous SAPO-5 under the same conditions for catalytic cracking of 1,3,5-triisopropylbenzene heavy *** remarkable catalytic reactivity was mainly attributed to the presence of the hierarchical porosity in the silicoaluminophosphate catalyst.

关键词： micro-mesoporous silicoaluminophosphate controlled morphology catalytic cracking large molecule

Evaluation of lightning-induced overvoltage on a 10 kV distribution line based on electromagnetic return-stroke model using finite-difference time-domain

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High Voltage 2024年第2期9卷 356-366页

作者： Pan Duan Lianfang Zhang Xiaogang Huang jian sun Yue qi qing Yang School of Automation Chongqing University of Posts and TelecommunicationsChongqingChina Chongqing Power Co Tongnan BurChongqingChina China Southern Power Grid Science Research Institute GuangzhouChina State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina

Accurate simulation of lightning-induced overvoltage for overhead distribution lines is helpful to prevent lightning trip *** electromagnetic return-stroke model was used to represent lightning and then a 3D finite-difference time-domain(FDTD)method was adopted to simulate the lightning-induced overvoltage on a distribution line without a field-line coupling *** lightning-induced overvoltage behave for different ground conductivity and varying distance between the distribution line and the lightning channel was *** results showed that the overvoltage waveforms at the centre point of the line corresponding to lightning strikes on the lossy ground and an ideal ground(σ=∞)were similar;however,the peak amplitudes of the waveform were affected by soil conductivity at a close *** relationship between magnitude of the overvoltage and distance can be described by a second-order exponential decay ***,the overvoltage calculated using the proposed model was compared with those obtained based on Agrawal's model and measurements made using the newly developed intelligent insulator on *** these comparisons,it could be concluded that the FDTD method with the electromagnetic return-stroke model produces reasonably accurate results of the attenuated oscillation waveform,which can better reproduce the overvoltage on operational distribution lines.

关键词： lightning distribution return

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装配式后植锚固筋混凝土预制叠合板施工

建筑技术开发 2021年第23期48卷 32-33页

作者：钱廷洋乔志鲁孙建齐王利明中国建筑第二工程局有限公司天津300300

在概述装配式混凝土预制叠合板技术优势的基础上,以某高层建筑项目为例,指出其叠合板预留锚固钢筋与梁体横向钢筋之间所存在的矛盾,并提出后植锚固筋叠合板施工技术方案,进而对该项目装配式后植锚固筋混凝土预制叠合板施工技术要点进行... 详细信息

在概述装配式混凝土预制叠合板技术优势的基础上,以某高层建筑项目为例,指出其叠合板预留锚固钢筋与梁体横向钢筋之间所存在的矛盾,并提出后植锚固筋叠合板施工技术方案,进而对该项目装配式后植锚固筋混凝土预制叠合板施工技术要点进行分析探讨。结果表明,装配式后植锚固筋混凝土预制叠合板施工技术能有效克服传统混凝土叠合板施工时所存在的预留锚固钢筋和梁体横向水平筋之间存在冲突的弊端,避免叠合板根部抗剪力受损,并能保证施工进度和施工质量,该处理措施可推广应用于我国建筑工程中装配式预制叠合板施工过程。

关键词：后植锚固筋装配式预制叠合板

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发电厂侧AVC子站电压控制策略研究和实现

甘肃冶金 2014年第6期36卷 127-130页

作者：蔡兆顺孙启建常新海刘丽君酒钢(集团)宏晟电热有限公司甘肃嘉峪关735100 山东鲁电调试运行技术有限公司山东济南250014

电压是电网电能质量的一项关键指标,对其控制关系到电网安全、稳定、经济运行,AVC系统是实现电网电压稳定控制的有效手段,本文以某公司四台350MW火电单元机组AVC系统控制策略、调试及投入效果为分析对象,对基于发电厂侧的AVC三级电压控... 详细信息

电压是电网电能质量的一项关键指标,对其控制关系到电网安全、稳定、经济运行,AVC系统是实现电网电压稳定控制的有效手段,本文以某公司四台350MW火电单元机组AVC系统控制策略、调试及投入效果为分析对象,对基于发电厂侧的AVC三级电压控制策略进行研究。

关键词： AVC 电压无功功率

Mechanics criterion and factors affecting overburden stability in solid dense filling mining

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International Journal of Mining Science and Technology 2017年第3期27卷 407-413页

作者： sun jian School of Energy and Safety Anhui University of Science & Technology State Key Laboratory for Geomechanics & Deep Underground Engineering China University of Mining & Technology

The effect of controlling strata movement in solid filling mining depends on the filling rate of the goal. However, the mechanical property of the overburden in the backfill stope and the designed size of the backfill mining workface should also be considered. In this study, we established a main roof strata model with loads in accordance with the theory of key strata to investigate the stability of the overburden in solid dense filling mining. We analyzed the stress distribution law of the main roof strata based on elastic thin plate theory. The results show that the position of the long side midpoint of the main roof strata failed more easily because of tensile yield, indicating that this position is the area where failure is likely to occur more easily. We also deduced the stability mechanics criterion of the main roof strata based on tensile yield criterion. The factors affecting the stability of the overburden in solid dense filling mining were also analyzed, including the thickness and elasticity modulus of the main roof strata, overlying strata loads, advanced distance and length of workface, and elastic foundation coefficient of backfill body. The research achievements can provide an important theoretical basis for determining the designed size of the solid dense filling mining workface.

关键词： Filling mining Strata movement Stability control Influencing factors Size design