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Semiconductor/relaxor 0-3 type composites without thermal depolarization in Bi0.5Na0.5TiO3-based lead-free piezoceramics

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Semiconductor/relaxor 0-3 type composites without thermal de...

Novel lead-free NaNbO_(3) -based relaxor antiferroelectric ceramics with ultrahigh energy storage density and high efficiency

第十七届全国晶体生长与材料学术会议(CCCG-17)

作者： shan tao Zhang National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering College of Engineering and Applied Science&Collaborative Innovation Center of Advanced MicrostructuresNanjing University

Commercial lead-based piezoelectric materials raised world-wide environmental concerns in the past ***

关键词： Bi0.5Na0.5TiO3 thermal depolarization composite

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Journal of Materiomics 2022年第2期8卷 295-301页

作者： Jie Jiang Xiongjie Li Ling Li Shun Guo Ji Zhang Jing Wang Heguo Zhu Yiping Wang shan-tao Zhang School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied Science&Jiangsu Key Laboratory of Artificial Functional Materials&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

The development of environmentally friendly ceramics for electrostatic energy storage has drawn growing interest due to the wide application in high power and/or pulsed power electronic ***,it is difficult to simultaneously achieve ultrahigh recoverable energy storage density(W rec>8 J/cm^(3))and high efficiency(η>80%),which restricts their application in the miniaturized,light weight and easy integrated electronic ***,the novel NaNbO_(3)-(Bi_(0.8)Sr_(0.2))(Fe_(0.9) Nb_(0.1))O_(3) relaxor antiferro-electric ceramics,which integrates the merits of antiferroelectrics and relaxors,are demonstrated to exhibit stabilized antiferroelectric phase and enhanced dielectric relaxor *** particular impor-tance is that the 0.88NN-0.12BSFN ceramic achieves giant electric breakdown strength E_(b)=98.3 kV/mm,ultrahigh W _(rec)=16.5 J/cm^(3) and high h=83.3%,as well as excellent frequency,cycling and thermal reliability *** comprehensive energy storage performance of NN-BSFN not only out-performs state-of-the-art dielectric ceramics by comparison,but also displays outstanding potential for next-generation energy storage capacitors.

关键词： Lead-free NaNbO_(3) Relaxor antiferroelectric Energy storage property

Micro RNA-548a-5p promotes proliferation and inhibits apoptosis in hepatocellular carcinoma cells by targeting Tg737

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World Journal of Gastroenterology 2016年第23期22卷 5364-5373页

作者： Ge Zhao Ting Wang Qi-Ke Huang Meng Pu Wei Sun Zhuo-Chao Zhang Rui Ling Kai-shan tao Department of Hepatobiliary Surgery Xijing HospitalFourth Military Medical University Department of Thyroid Breast and Vascular SurgeryXijing HospitalFourth Military Medical University

AIM: To investigate whether Tg737 is regulated by micro RNA-548a-5p(mi R-548a-5p), and correlates with hepatocellular carcinoma(HCC) cell proliferation and ***: Assays of loss of function of Tg737 were performed by the colony formation assay, CCK assay and cell cycle assay in HCC cell lines. The interaction between mi R-548a-5p and its downstream target, Tg737, was evaluated by a dual-luciferase reporter assay and quantitative real-time polymerase chain reaction. Tg737 was then up-regulated in HCC cells to evaluate its effect on mi R-548a-5p regulation. Hep G2 cells stably overexpressing mi R-548a-5p or mi R-control were also subcutaneously inoculated into nude mice to evaluate the effect of mi R-548a-5p up-regulation on in vivo tumor growth. As the final step, the effect of mi R-548a-5p on the apoptosis induced by cisplatin was evaluated by flow ***: Down-regulation of Tg737, which is a target gene of mi R-548a-5p, accelerated HCC cell proliferation, and mi R-548a-5p promoted HCC cell proliferation in vitro and in vivo. Like the downregulation of Tg737, overexpression of mi R-548a-5p in HCC cell lines promoted cell proliferation, increased colony forming ability and hampered cell apoptosis. In addition, mi R-548a-5p overexpression increased HCC cell growth in vivo. Mi R-548a-5p downregulated Tg737 expression through direct contact with its 3' untranslated region(UTR), and mi R-548a-5p expression was negatively correlated with Tg737 levels in HCC specimens. Restoring Tg737(without the 3'UTR) significantly hampered mi R-548a-5p induced cell proliferation, and rescued the mi R-548a-5p induced cell proliferation inhibition and apoptosis induced by ***: Mi R-548a-5p negatively regulates the tumor inhibitor gene Tg737 and promotes tumorigenesis in vitro and in vivo, indicating its potential as a novel therapeutic target for HCC.

关键词： micro RNA-548a-5p Tg737 Proliferation Apoptosis Hepatocellular carcinoma cells

基于波束聚焦的外辐射源雷达干扰抑制技术研究

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兵工学报 2010年第12期31卷 1557-1561页

作者：王魁陶然单涛北京理工大学信息与电子学院北京100081

在利用非合作照射源的外辐射源雷达系统中,直达波及其形成的多径杂波干扰对雷达系统性能有非常严重的影响。通常采用的时域自适应滤波方法是:根据一定最优准则利用参考信号构建多径信道模型,对回波信号中的干扰进行对消。然而,当天线扫... 详细信息

在利用非合作照射源的外辐射源雷达系统中,直达波及其形成的多径杂波干扰对雷达系统性能有非常严重的影响。通常采用的时域自适应滤波方法是:根据一定最优准则利用参考信号构建多径信道模型,对回波信号中的干扰进行对消。然而,当天线扫描监视区域时,在积累时间内干扰信道发生变化,导致自适应对消器输出不再收敛,降低了干扰抑制能力。本文提出通过对各阵元信号加权补偿,使波束形成等效于聚焦的效果,在积累时间内维持信道特性,改善自适应对消器在雷达扫描状态下的性能。仿真和外场采集数据试验表明,该方法提升了外辐射源雷达时域自适应对消器在天线转动状态下的干扰抑制能力。

关键词：雷达工程外辐射源雷达干扰抑制

GCr15钢轴承残留奥氏体、尺寸精度及疲劳寿命试验研究

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金属热处理 2007年第9期32卷 90-92页

作者：钱坤陶姗杭州职业技术学院浙江杭州310018

对7205C/P5精密轴承和7205C/P4超精密轴承进行了工艺试验,并对不同的轴承热处理工艺,其残留奥氏体含量对尺寸精度稳定性及轴承疲劳寿命的影响进行试验研究,提出了GCr15钢制超精密轴承残留奥氏体的控制量。

关键词：超精密轴承残留奥氏体尺寸稳定性疲劳寿命

Palliative operation procedures for pancreatic head carcinoma

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Hepatobiliary & Pancreatic Diseases International 2002年第1期1卷 133-136页

作者： Kai-shan tao Yong-Gang Lu Ke-Feng Dou From the Department of Hepatobiliary Surgery, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China Department of Hepatobiliary Surgery Xijing Hospital Fourth Military Medical University Xi'an 710032 China. taokaishan@***

Objective: To investigate the procedure choice of pal-liative operation for carcinoma of the head of the pan-creas (CHP).Methods: The clinical data from 187 patients withCHP treated in the last 20 years were analyzed ***: The operation mortality rate was 8.6%, themortality of hepatic duct-jejunostomy (HDJS) was nothigher than that of cholecystojejunostomy (CJS) (P>0.05). The postoperative relapse of jaundice and cholan-gitis was significantly lower than that of CJS (P0.05), whereas the survival was significantlyhigher than that of the simple procedure without GJS(P<0.01). The occurrence of duodenal obstructionafter HDJS or CJS was 29.3%.Conclusion: As a palliative operation, Roux-en-Y chole-dochojejunostomy especially in combination with pre-ventive gastrojejunostomy is strongly recommended.

关键词： pancreatic neoplasms anastomosis Roux-en-Y follow-up studies

Spatial learning and memory deficits in young adult mice exposed to a brief intense noise at postnatal age

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Journal of Otology 2015年第1期10卷 21-28页

作者： shan tao Lijie Liu Lijuan Shi Xiaowei Li Pei Shen Qingying Xun Xiaojing Guo Zhiping Yu Jian Wang Department of Physiology Medical College of Southeast University Children's Medical Center the Second Affiliated Hospital of Nanjing Medical University School of Human Communication Disorders Dalhousie University

Noise pollution is a major hazardous factor to human health and is likely harmful for vulnerable groups such as pre-term infants under lifesupport system in an intensive care unit. Previous studies have suggested that noise exposure impairs children’s learning ability and cognitive performance and cognitive functions in animal models in which the effect is mainly attributed to the oxidant stress of noise on the cognitive brain. The potential role of noise induced hearing loss(NIHL), rather than the oxidant stress, has also been indicated by a depression of neurogenesis in the hippocampus long after a brief noise exposure, which produces only a tentative oxidant stress. It is not clear if noise exposure and NIHL during early development exerts a long term impact on cognitive function and neurogenesis towards adulthood. In the present study, a brief noise exposure at high sound level was performed in neonatal C57BL/6J mice(15 days after birth) to produce a significant amount of permanent hearing loss as proved 2 months after the noise. At this age, the noise-exposed animals showed deteriorated spatial learning and memory abilities and a reduction of hippocampal neurogenesis as compared with the control. The averaged hearing threshold was found to be strongly correlated with the scores for spatial learning and memory. We consider the effects observed are largely due to the loss of hearing sensitivity, rather than the oxidant stress, due to the long interval between noise exposure and the observations.

关键词： Noise induced hearing loss Neonatal mice Learning

Low-temperature sintered(Na_(1/2)Bi_(1/2))TiO_(3)-based incipient piezoceramics for co-fired multilayer actuator application

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Journal of Materiomics 2019年第3期5卷 480-488页

作者： Pengyuan Fan Yangyang Zhang shan-tao Zhang Bing Xie Yiwei Zhu Mohsin Ali Marwat Weigang Ma Kai Liu Liang Shu Haibo Zhang School of Materials Science andEngineering State Key Laboratory of Material ProcessingDie&Mould TechnologyHuazhong University of Science and TechnologyWuhan430074China Information Engineering Institute Huanghe Science and Technology CollegeZhengzhou450000China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied ScienceCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China Research Centre for Functional Ceramics Ministry of EducationHuazhong University of Science and TechnologyWuhan430074China

Low-temperature sintered(Na_(1/2)Bi_(1/2))_(0.935)Ba_(0.065)Ti_(0.975)(Fe_(1/2)Nb_(1/2))_(0.025)O_(3)(NBT-BT-0.025FN)lead-free incipient piezoceramics were investigated using high-purity Li_(2)CO_(3) as sintering *** the ≤0.5 wt%Li_(2)CO_(3) addition,the introduced Li^(+) cations precede to enter the A-sites of the perovskite lattice to compensate for the A-site *** the addition exceeds 0.5 wt%,the excess Lit cations will occupy B-sites and give rise to the generation of oxygen vacancies,which accelerate the mass transport and thus lower the sintering temperature effectively from 1100℃ down to 925℃.It was also found that a small amount of Lit addition has little effect on the phase structure and electromechanical properties of the system,but overweight seriously disturbs these characteristics because of the large lattice *** sintered NBT-BT-0.025FN incipient piezoceramics with 1.25 wt%Li_(2)CO_(3) addition at 925℃ provides a large strain of 0.33% and a corresponding large signal piezoelectric coefficient d_(33)^(*) of 550 pm/V at 60 kV/cm,indicating this system is a very promising candidate for lead-free co-fired multilayer actuator application.

关键词： Lead-free piezoceramics (Na_(1/2)Bi_(1/2))TiO_(3) Low-temperature sintering Electric-field-induced strain

Procedures for congenital choledochal cysts and curative effect analysis in adults

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Hepatobiliary & Pancreatic Diseases International 2002年第3期1卷 442-445页

作者： Kai-shan tao Yong-Gang Lu Ting Wang Ke-Feng Dou the Department of Hepatobiliary Surgery, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China Department of Hepatobiliary Surgery Xijing Hospital Fourth Military Medical University Xi'an 710032 China. taokaishan@***

Objective: To evaluate the procedures and timing of operation as well as long-term postoperative effect of congenital choledochal cysts (CCC) in adults. Methods: The procedures and timing of operation, effective rate, re-operation rate and incidence of car- cinoma after operation for 70 adult patients with CCC from January 1980 to June 1999 were analyzed retrospectively. Results: The re-operation rate of external drainage was 86% (6/7). The effective rate of internal drain- age was significantly lower than that of cyst resection (3/10 vs 45/49, X^2=20. 94, P<0.001). The re-op- eration rate and incidence of carcinoma of internal drainage were higher than those of cyst resection (5/ 10 vs 3/49, X^2=13. 64, P<0. 001 and 3/10 vs 3/49, X^2=5. 18, P<0. 025). The reoperation rate of e- mergency surgery was higher than that of selective operation (8/10 vs 6/56, X^2=24. 37, P<0.001). Conclusions: External drainage should be the first- aid measure and the therapy of choice on emergency basis. Internal drainage should never be attempted. Cyst resection with Roux-en-Y hepaticojejunostomy is recommended as the treatment of choice in selective operation.

关键词： choledochal cyst drainage surgical procedure