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Improving the thermal shock resistance of ceramics by crack arrest blocks

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Science China(Technological Sciences) 2016年第6期59卷 913-919页

作者： WANG Yan Wei xia biao SU Hong Hong CHEN Hang FENG Xue Applied Mechanics Laboratory Department of Engineering Mechanics Tsinghua University Center for Mechanics and Materials Tsinghua University Department of Engineering Mechanics Chongqing University

Ceramics used in the high temperature environment are inevitably subjected to sudden temperature change, which may lead to catastrophic thermal shock failure due to the intrinsic brittleness of ceramics. In this paper, an experimental platform is designed to realize the in-situ observation during the thermal shock experiments. Experimental results show that all the cracks initiate from one of the edge midpoints and propagate to another one for square specimens. Such experimental observation is consistent with the maximum tensile stress zone with the maximum temperature gradient given by the finite element method(FEM). The different crack modes resulting from different heating rates after thermal shock experiments are observed and analyzed. Comparison between different clamping methods is conducted to study the effects of boundary conditions on the thermal shock experiments. Furthermore, in order to improve the thermal shock performance of alumina ceramics, crack arrest blocks are added near the edge midpoint. The thickness, shape and arrangement of the blocks are systematically investigated to understand the mechanism of improvement of thermal shock resistance.

关键词： thermal shock ultra-high temperature ceramics crack arrest blocks in-situ dynamic observation

Comprehensive evaluation of chemical breakers for multistage network ultra-high strength gel

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Petroleum Science 2023年第5期20卷 2864-2878页

作者： Zheng Kang Hu Jia Zhong-Guo Li biao xia Yi Wang Yong Jiang Han-Lin Peng Petroleum Engineering Technology Institute of Southwest Petroleum Branch SINOPECDeyang618000SichuanChina National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation of Southwest Petroleum University Chengdu610500SichuanChina SINOPEC Southwest Petroleum Engineering Company Deyang618000SichuanChina

Polymer gels have been accepted as a useful tool to address many sealing operations such as drilling and completion,well stimulation,wellbore integrity,water and gas shutoff,***,we developed an ultra-high strength gel(USGel)for medium to ultra-low temperature ***,the removal of USGel is a difficult problem for most temporary plugging *** paper first provides new insights into the mechanism of USGel,where multistage network structure and physical entanglement are the main reasons for USGel possessing ultra-high *** the effects of acid breakers,encapsulated breakers,and oxidation breakers(including H_(2)O_(2),Na_(2)S_(2)O_(8),Ca(ClO)_(2),H_(2)O_(2)+NaOH,Na_(2)S_(2)O_(8)+NaOH,and Ca(ClO)_(2)+NaOH)were *** effects of component concentration and temperature on the breaking solution were studied,and the corrosion performance,physical simulation and formation damage tests of the breaking solution were carried *** final formulation of 2%-4%NaOH+4.5%-6%H_(2)O_(2) breaking solution was determined,which can make USGel completely turn into water at 35e105*** combinations of“acid t breaking solution”,“acid+encapsulated breaker”and“encapsulated breaker+breaking solution”were evaluated for breaking *** acid gradually reduced the volume of USGel,which increased the contact area between breaking solution and USGel,and the effect of“4%acid+breaking solution”was 23 times higher than that of breaking solution alone at 35***,the acid significantly reduced the strength of *** paper provides new insights into the breaking of high-strength gels with complex network structures.

关键词： Gel breaking Polymer gel Ultra-high strength Chemical breakers Multistage network

Expression and localization of Wolfram syndrome 1 gene in the developing rat pancreas

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World Journal of Gastroenterology 2009年第43期15卷 5425-5431页

作者： Rong Xu biao xia Jie Geng Jing Shi Hui Shi Li Yuan Wei De Department of Biochemistry and Molecular Biology Nanjing Medical University Nanjing 210029 Jiangsu Province China First School-of Clinical Medicine Nanjing Medical University Nanjing 210029 Jiangsu Province China

AIM： To investigate the expression and function of Wolfram syndrome 1 gene （WFS1） during the development of normal pancreas. METHODS： Pancreas from Sprague-Dawley rat fetuses, embryos, young and adult animals were used in this study. Expression levels of WFS1 in pancreas of different development stages were detected by reverse transcription-polymerase chain reation （RT-PCR） and Western blotting. To identify the cell location of WFS1 in the developing rat pancreas, double-immunofluorescent staining was performed using antibodies to specific cell markers and WFS1, respectively. RESULTS： Compared to E15.5, the highest level of WFSl mRNA was detected at E18.5, the level of WFSl mRNA in E15.5 and P0 was less, and at a lowest at adult （P 〈 0.05 vs P0 and adult）, respectively. Compare to E15.5, the highest level of WFS1 was at P14 and lowest at P21 （P 〈 0.05 vs P14 and P21）, respectively. The WFSl positive staining is expressed in the normal developing rat pancreas mainly in the islet beta-cells and mesenchyme at each stage tested. CONCLUSION： These results indicate that WFSl may be involved in some aspects of pancreatic development and further research on WFS1 may provide new evidences to prove the interactions between mesenchyma and epithelia at the same time.

关键词： Wolfram syndrome 1 Pancreas Morphogenesis Mesenchyme Pancreatic beta cells

Extended π-conjugated N-containing heteroaromatic hexacarboxylate organic anode for high performance rechargeable batteries

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Journal of Energy Chemistry 2020年第12期29卷 303-311页

作者： Shu-biao xia Teng Liu Wen-Jin Huang Hong-Bo Suo Fei-xiang Cheng Hong Guo Jian-Jun Liu Center for Yunnan-Guizhou Plateau Chemical Functional Materials and Pollution Control Qujing Normal UniversityQujing 655011YunnanChina School of Pharmacy Liaocheng UniversityLiaocheng 252059ShandongChina School of Materials Science and Engineering Yunnan UniversityKunming 650091YunnanChina

Organic electrode materials are desirable for green and sustainable Li-ion batteries(LIBs) due to their light-weight, low cost, abundance and multi-electron transfer reactions during battery operation. However, the successful utilization of organic electrodes is hindered by their poor electrical conductivity and low cyclic stability. Herein, a facile synthesis of π-conjugated N-containing heteroaromatic hexacarboxylate(Li6-HAT) compound and its electrochemical performance as an anode material in LIBs is *** as-synthesized Li6-HAT electrode renders an ultrahigh initial capacity of 1126.3 m Ah g^(-1) at the current density of 100 m A g^(-1). Moreover, π-conjugated N-containing heteroaromatic center provide excellent reversibility of(de)lithiation process, resulting in excellent capacity retention. Furthermore, a combination of density functional theory(DFT) calculations, in-situ Fourier transform infrared(FTIR) and ex-situ X-ray photoelectron spectroscopy(XPS) characterization reveal that the π-conjugated nitrogen and carboxyl oxygen act as electrochemically active sites during the charge/discharge process. The current work provides novel insights into the charge storage mechanism of organic electrodes and opens up avenues for further development and utilization of organic electrodes in Li-ion batteries.

关键词： Li-ion batteries Hexacarboxylate π-conjugated compounds N-containing Organic anode

Improving the Intermittent Discharge Performance of Mg–Air Battery by Using Oxyanion Corrosion Inhibitor as Electrolyte Additive

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Acta Metallurgica Sinica(English Letters) 2016年第11期29卷 1019-1024页

作者： Yan-Chun Zhao Guang-Sheng Huang Gui-lin Gong Ting-Zhuang Han Da-biao xia Fu-Sheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University

A widely used oxyanion corrosion inhibitor（Li2CrO4） was used as electrolyte additive（3.5 wt% Na Cl solution was used as electrolyte solution） for Mg–air battery. The potentiodynamic polarization tests showed that the presence of 0.1 wt% Li2CrO4in the Na Cl electrolyte reduced enormously the corrosion current density of the tested AZ31 Mg *** to the intermittent discharge tests, the use of 0.1 wt% Li2CrO4 as electrolyte additive increased the anode efficiency of the Mg–air battery by 28.4%. The addition of 0.1 wt% Li2CrO4reduced the anode self-corrosion rate of the battery in the intermittent stage effectively. The product film after discharge was observed by scanning electron microscope, and the Mg–air battery containing 0.1 wt% Li2CrO4has a loose product film, which is beneficial to its discharge performance. So using Li2CrO4 as electrolyte additive could improve the intermittent discharge performance of Mg–air battery. And the use of oxyanion corrosion inhibitor as electrolyte additive may be an excellent way to improve the intermittent discharge performance of Mg–air battery.

关键词： Mg alloys Corrosion Mg-air battery Intermittent discharge performance Anode efficiency

Enhanced methanol oxidation activity of Au@Pd nanoparticles supported on MWCNTs functionalized by MB under ultraviolet irradiation

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Rare Metals 2015年第1期34卷 12-16页

作者： Ming-Li Xu Xi-Kun Yang Ying-Jie Zhang Shu-biao xia Peng Dong Guo-Tao Yang Faculty of Science Kunming University of Science and Technology Research Center for Analysis and Measurement Kunming University of Science and Technology Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology

A successful approach to assemble Au core Pd shell （Au@Pd） nanoparticles on the surface of multi-walled carbon nanotubes functionalized by methylene blue （MB）（Au@Pd/fuv-MWCNTs） was reported. In this method, MWCNTs were functionalized under ultraviolet irradiation. UV-Vis analysis and high-angle annular dark-field trans- mission electron microscope （HAADF-TEM） image prove that core-shell structure of Au@Pd nanoparticles forms. TEM results indicate that Au@Pd nanoparticles （ - 5.2 nm） are well-dispersed on the surface of fuv-MWCNTs. X-ray photoelectron spectroscopy （XPS） reveals that ultraviolet irradiation can promote the interaction between Au@Pd nanoparticles and the functional groups on the surface of MWCNTs. Cyclic voltammograms （CV）, chronoampero- grams （CA）, and electrochemical impedance spectroscopy （EIS） results demonstrate that the Au@Pd/fuv-MWCNTs catalysts show excellent electrocatalytic performance for methanol oxidation in alkaline media. The catalytic activity of the Au@Pd/fuv-MWCNTs is ~ 2 times higher than that of the commercial Pd/C catalysts. This is mostly attributed to that ultraviolet irradiation can make the moieties of MB provide a uniform surface with active and anchoring sites, and improves the functional effect of MB on the surface of MWCNTs. Especially, ultraviolet irradiation modifies electronic structure of Pd and is beneficial for the enhance- ment of catalytic activity.

关键词： Au@Pd core-shell nanoparticle Multi-walledcarbon nanotube Methylene blue Electrocatalyst Methanol oxidation Ultraviolet irradiation

WY区块深层页岩气井压后返排规律及制度研究

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油气井测试 2024年第4期33卷 1-8页

作者：刘殷韬康正夏彪张国东蒋勇彭翰林中石化西南油气分公司石油工程技术研究院四川德阳618000 中石化西南石油工程有限公司四川德阳618000

合理的深层页岩气井压后返排制度有利于改善单井产量、延长稳产周期。基于WY区块页岩气91口井的现场数据,采用重点井筛选、示踪剂分析、井例论证等方法,明确了返排规律,建立了WY区块页岩气压后返排制度。结果表明,压-焖-关(压裂+焖井+... 详细信息

合理的深层页岩气井压后返排制度有利于改善单井产量、延长稳产周期。基于WY区块页岩气91口井的现场数据,采用重点井筛选、示踪剂分析、井例论证等方法,明确了返排规律,建立了WY区块页岩气压后返排制度。结果表明,压-焖-关(压裂+焖井+返排期间关井)和压-焖时间主要在500~1500 h之间,大部分井能在48 h内见气,见气返排率在1%以内;测试产量和稳产后半年单位压降产量随压-焖-关时间的增加先增加后减少,见稳产时间和见气时间随压-焖时间的增加而降低;产层为龙马溪组2小层的井,推荐压-焖-关时间为1000~1200 h;存在最优测试返排率,油嘴调整应该以“最优测试返排率、控砂、控压”为原则。研究结果为深层页岩气井压后排采制度的建立提供了新思路。

关键词：深层页岩气压后返排返排制度 WY区块返排规律焖井时间油嘴

Incidence and mortality of liver cancer in China, 2010

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Chinese Journal of Cancer 2014年第8期33卷 388-394页

作者： Kuang-Rong Wei xia Yu Rong-Shou Zheng xia-biao Peng Si-Wei Zhang Ming-Fang Ji Zhi-Heng Liang Zhi-Xiong Ou Wan-Qing Chen Cancer Institute Zhongshan Municipal People’s HospitalZhongshan Guangdong National Central Cancer Registry National Cancer CenterBeijing Digestive Internal Department Zhongshan Municipal People’s HospitalZhongshan Guangdong

Liver cancer is a common malignant tumor in China and a major health concern. We aimed to estimate the liver cancer incidence and mortality in China in 2010 using liver cancer data from some Chinese cancer registries and provide reference for liver cancer prevention and treatment. We collected and evaluated the incidence and mortality data of liver cancer in 2010 from 145 cancer registries, which were included in the 2013 Chinese Cancer Registry Annual Report, calculated crude, standardized, and truncated incidences and mortalities, and estimated new liver cancer cases and deaths from liver cancer throughout China and in different regions in 2010 from Chinese practical population. The estimates of new liver cancer cases and deaths were 358,840 and 312,432, respectively, in China in 2010. The crude incidence, age-standardized rate by Chinese standard population(ASR China), and age-standardized rate by world standard population(ASR world) were 27.29/100,000, 21.35/100,000, and 20.87/100,000, respectively; the crude, ASR China, and ASR world mortalities were 23.76/100,000, 18.43/100,000, and 18.04/100,000, respectively. The incidence and mortality were the highest in western regions, higher in rural areas than in urban areas, and higher in males than in females. The age-specific incidence and mortality of liver cancer showed a rapid increase from age 30 and peaked at age 80-84 or 85+. Our results indicated that the 2010 incidence and mortality of liver cancer in China, especially in undeveloped rural areas and western regions, were among high levels worldwide. The strategy for liver cancer prevention and treatment should be strengthened.

关键词：中国标准死亡率肝癌世界人口死亡病例恶性肿瘤西部地区农村地区

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三维编织复合材料热物理性能的有限元分析

航空学报 2011年第6期32卷 1040-1049页

作者：夏彪卢子兴北京航空航天大学航空科学与工程学院北京100191

根据三维编织复合材料的细观结构,分别建立了三维四向和五向编织复合材料热物理性能的有限元模型。采用周期性的非绝热温度边界条件和位移边界条件,计算了三维四向和五向编织复合材料的整体等效热传导系数和热膨胀系数,计算结果同已有... 详细信息

根据三维编织复合材料的细观结构,分别建立了三维四向和五向编织复合材料热物理性能的有限元模型。采用周期性的非绝热温度边界条件和位移边界条件,计算了三维四向和五向编织复合材料的整体等效热传导系数和热膨胀系数,计算结果同已有文献相比与实验值符合得更好。在此基础上,进一步研究了编织角、纤维体积分数、编织结构等参数对材料热物理性能的影响规律。结果表明,三维编织复合材料的热物理性能具有明显的各向异性,热膨胀性能随参数的变化规律相比热传导性能更具非线性特征。且所得结果与实验值符合较好,证实了本文模型的有效性,为材料热学问题和力热耦合问题的分析提供了有用参考。

关键词：三维编织热传导热膨胀有限元单胞