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Fe Nanoparticle Production by an Atmospheric Cold Plasma Jet

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Chinese Physics Letters 2010年第6期27卷 244-245页

作者： zhang yu-tao Guo Ying WANG Da-Wang FENG Yan MA Teng-Cai School of Physics Hunan University of Science and Technology Xiangtan 411201 School of Computer Science and Engineering Hunan University of Science and Technology Xiangtan 411201 Key Laboratory of Materials Modification by Laser Ion and Electron Beams (Ministry of Education) Dalian University of Technology Dalian 116024

We present a simple method of producing Fe nanoparticles based on the dissociation of ferrocene by a simple single electrode atmospheric cold argon plasma jet. The system ＆ driven by a sinusoidal ac-supply with a peak voltage of 0-30 k V and a frequency of 50kHz. The average size of iron na^opartieles analyzed by scanning electron microscopy is about 10-30nm for the gas phase samples, and 30-l00nm for the liquid phase samples. The method should be competitive due to its simplicity and low cost.

关键词： NANOPARTICLES IRON LOW temperature plasmas DISSOCIATION (Chemistry) FERROCENE PLASMA jets SCANNING electron microscopy

Introduction of firefighting methods in U.S. underground mines

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西安科技大学学报 2011年第6期31卷 672-678,697页

作者： zhang Xi-chen zhang yu-tao Jerry C. Tien Missouri University of Science and Technology Rolla MO

Underground mine fire always exists since the mining activity was *** poses a severe safety hazard to the mine workers and may also cause a tremendous economic loss to the *** for controlling and extinguishing fires in underground mine have long been studied and there have been significant *** order to know clearly about the firefighting technology used,this paper summarizes most of the underground mine firefighting methods used in the United States the past 150 *** paper describes not only the accepted firefighting theories,but also the technologies,both direct and indirect attacking,in accordance to regulations or codes,with special attention is given to the indirect attack method and its related *** research needed is also briefly discussed at the end of this paper.

关键词： firefighting extinguishing agent attack method remote sealing

Evaluation of the propensity for coal spontaneous combustion based on catastrophe theory

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 265-269页

作者： zhang yu-tao zhang Xi-chen TIEN Jerry C LI Ya-qing Missouri University of Science ＆ Technology Rolla MO USA

Generally, different prevention measures should be taken according to spontaneous combustion propensities. The current methods to evaluate the propensity of coal spontaneous combustion, such as chromatographic method of oxygen adsorption, oxidation kinetics method and activation energy method, are mostly affected by human factors. Their boundaries among different classes of propensities were all established by subjective judgments. A new evaluation method using catastrophe theory is introduced. This method can accurately depict the process of coal spontaneous combustion and the evaluation index, ＂catastrophe temperature＂, be obtained based on the model. In terms of catastrophe temperature, the spontaneous combustion propensity of different coals can be sequenced. Experimental data indicate that this method is appropriate to describe the spontaneous combustion process and to evaluate the propensity of coal svontaneous combustion.

关键词： spontaneous combustion catastrophe theory catastrophe temperature

Automatic detection of prohibited items with small size in X-ray images

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Optoelectronics Letters 2020年第4期16卷 313-317页

作者： zhang yu-tao zhang Hai-gang ZHAO Teng-fei YANG Jin-feng Tianjin Key Laboratory for Advanced Signal Processing Civil Aviation University of ChinaTianjin 300300China Shenzhen Polytechnic Shenzhen 518055China

In this paper,we focus on the detection of prohibited items with small size,and establish an automatic detection model based on feature fusion single shot multibox detector(FSSD)*** modifications are carried out to improve the detection ***,the semantic enrichment module(SEM)with dilated convolution is applied to extract the low level feature with strong semantic ***,a residual module(Res)with residual blocks is added in the multibox detection architecture in order to extract more adequate features for target *** simulation results have demonstrated a better performance of the proposed detection model for prohibited items with small size compared with the state-of-the-arts.

关键词： size items bite

A STUDY OF THE INFLUENCE OF MICROPHYSICAL PROCESSES ON TYPHOON NIDA(2016) USING A NEW DOUBLE-MOMENT MICROPHYSICS SCHEME IN THE WEATHER RESEARCH AND FORECASTING MODEL

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Journal of Tropical Meteorology 2018年第2期24卷 123-130页

作者： LI Zhe zhang yu-tao LIU Qi-jun FU Shi-zuo MA Zhan-shan Numerical Weather Prediction Center of CMA Beijing 100081 China National Meteorological Center CMA Beijing 100081 China Department of Atmospheric and Oceanic Sciences Peking University Beijing 100871 China

The basic structure and cloud features of Typhoon Nida(2016) are simulated using a new microphysics scheme(Liuma) within the Weather Research and Forecasting(WRF) model. Typhoon characteristics simulated with the Liuma microphysics scheme are compared with observations and those simulated with a commonly-used microphysics scheme(WSM6). Results show that using different microphysics schemes does not significantly alter the track of the typhoon but does significantly affect the intensity and the cloud structure of the typhoon. Results also show that the vertical distribution of cloud hydrometeors and the horizontal distribution of peripheral rainband are affected by the microphysics scheme. The mixing ratios of rain water and graupel correlate highly with the vertical velocity component and equivalent potential temperature at the typhoon eye-wall region. According to the simulation with WSM 6 scheme,it is likely that the very low typhoon central pressure results from the positive feedback between hydrometeors and typhoon intensity. As the ice-phase hydrometeors are mostly graupel in the Liuma microphysics scheme, further improvement in this aspect is required.

关键词： Liuma microphysics scheme typhoon intensity cloud microphysics typhoon structure Weather Research and Forecasting model

Reoperation on aortic disease in patients with previous aortic valve surgery

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Chinese Medical Journal 2013年第18期126卷 3511-3514页

作者： SUN Xiao-gang zhang Liang yu Cun-tao QIAN Xiang-yang CHANG Qian State Key Laboratory of Cardiovascular Disease Fuwai Hospital National Center for Cardiovascular Disease Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background Aortic valve replacement （AVR） is a safe and effective method in the treatment of aortic valve diseases. This study aimed to increase the understanding on re-treatment of aortic diseases after aortic valve surgery through a retrospective analysis of 47 related cases. Methods Forty-seven patients （38 males and 9 females） with previous aortic valve surgery have received reoperation on aorta from January 2003 to June 2012, and the mean interval time of re-intervention to aortic disease was 6 years （（6.0＋ 3.8） years）. The secondary aortic surgery included aortic root replacement （14 cases）, ascending aorta replacement （10 cases）, aortic root/ascending aorta plus total arch replacement with stented elephant trunk implantation （21 cases）, and total thoracoabdominal aorta replacement （2 cases）. All these patients have received outpatient re-exams or follow-up by phone calls, Results After the initial aortic valve replacement, patients suffered from aortic dissection （25 cases, 53%）, ascending aortic aneurysm （12 cases, 26%） or aortic root aneurysm （10 cases, 21%）, Diameter in ascending aorta increased （5.2＋7.1） mm per year and aortic sinus （3.3＋3.1） mm per year. The annual growth value of diameter in ascending aorta was higher in patients with rheumatic heart disease than that in Marfan syndrome （P〈0,05）. All 47 patients have received reoperation on aorta. One patient died in operating room because aortic dissection seriously involved right coronary artery. Seven patients had renal insufficiency after operation; neurological complications occurred in 14 patients including 7 patients with stroke and the others with transient brain dysfunction. All patients were followed up, the mean survival time was （97.25~17.63） months, 95% confidence interval was 55.24-73.33 months. Eight cases were died during follow-up and five-year survival rate was 83%. Conclusion To reduce the aortic adverse events after first aortic valve surgery, it is necessary to actively treat and st

关键词： aortic valve replacement aortic disease reoperation

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宽光谱太阳能电池减反表面光谱特性研究

工程热物理学报 2015年第12期36卷 2689-2693页

作者：张玉涛宣益民南京理工大学能源与动力工程学院南京210094 南京航空航天大学能源与动力学院南京210016

本文利用时域有限差分方法,计算了三种不同的渐变折射率的单晶硅太阳能电池减反表面的光谱特性,对三种表面的减反性能进行了对比。讨论了结构参数对结构表面减反特性的影响,研究发现,蛾眼结构的单晶硅太阳能电池在整个太阳辐射光谱范围... 详细信息

本文利用时域有限差分方法,计算了三种不同的渐变折射率的单晶硅太阳能电池减反表面的光谱特性,对三种表面的减反性能进行了对比。讨论了结构参数对结构表面减反特性的影响,研究发现,蛾眼结构的单晶硅太阳能电池在整个太阳辐射光谱范围内具有最低的反射率,随着微结构高度的增加和周期的减小,有效折射率的梯度降低,减反效果更加明显。

关键词：宽光谱渐变折射率太阳能电池

科技金融对生产性服务业与制造业协同集聚的影响研究

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中国软科学 2018年第3期 47-55页

作者：张玉华张涛上海师范大学商学院上海200234

本文从产业地理集中与产业集聚角度测度了生产性服务业与制造业协同集聚水平,并利用2005-2015年我国省际间数据构建了动态空间杜宾模型,实证分析了生产性服务业与制造业协同集聚的空间相关性和空间溢出效应。研究结果表明:我国生产性服... 详细信息

本文从产业地理集中与产业集聚角度测度了生产性服务业与制造业协同集聚水平,并利用2005-2015年我国省际间数据构建了动态空间杜宾模型,实证分析了生产性服务业与制造业协同集聚的空间相关性和空间溢出效应。研究结果表明:我国生产性服务业与制造业协同集聚水平呈现空间集聚性,且协同集聚水平很大程度上受自身前期惯性的影响;科技金融主要通过研发经费投入和政府科技投入促进生产性服务业与制造业协同集聚发展。本文的研究为我国深化供给侧结构性改革提供了政策性启示。

关键词：科技金融协同集聚溢出效应

Loss-of-function mutations of microRNA-142-3p promote ASH1L expression to induce immune evasion and hepatocellular carcinoma progression

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World Journal of Gastroenterology 2025年第1期31卷 126-145页

作者： Xing-Hui yu Yan Xie Jian yu Kun-Ning zhang Zhou-Bo Guo Di Wang Zhao-Xian Li Wei-Qi zhang yu-Ying Tan Li zhang Wen-tao Jiang School of Medicine Nankai UniversityTianjin 300192China Tianjin Key Laboratory of Molecular Diagnosis and Treatment of Liver Cancer Tianjin First Center HospitalTianjin 300192China Department of Liver Transplantation Tianjin First Center HospitalTianjin 300192China First Central Clinical School Tianjin Medical UniversityTianjin 300192China

BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated *** therapeutic targets are beneficial to treat and predict the ***,the exact molecular mechanisms leading to the progression of HCC are still *** has shown that the microRNA-142-3p level decreases in HCC,whereas bioinformatics analysis of the cancer genome atlas database shows the ASH1L expression increased among liver tumor *** this paper,we will explore the effects and mechanisms of microRNA-142-3p and ASH1L affect the prognosis of HCC patients and HCC cell bioactivity,and the association between *** To investigate the effects and mechanisms of microRNA-142-3p and ASH1L on the HCC cell bioactivity and prognosis of HCC *** In this study,we grouped HCC patients according to their immunohistochemistry results of ASH1L with pathological tissues,and retrospectively analyzed the prognosis of HCC ***,explored the roles and mechanisms of microRNA-142-3p and ASH1L by cellular and animal experiments,which involved the following experimental methods:Immunohistochemical staining,western blot,quantitative real-time-polymerase chain reaction,flow cytometric analysis,tumor xenografts in nude mice,*** statistical methods involved in this study contained t-test,one-way analysis of variance,theχ^(2)test,the Kaplan-Meier approach and the log-rank *** In this study,we found that HCC patients with high expression of ASH1L possess a more recurrence rate as well as a decreased overall survival ***1L promotes the tumorigenicity of HCC and microRNA-142-3p exhibits reduced expression in HCC tissues and interacts with ASH1L through targeting the ASH1L 3′untranslated ***,microRNA-142-3p promotes apoptosis and inhibits proliferation,invasion,and migration of HCC cell lines in vitro via *** the exploration mechanism,we found ASH1L may promote an immunosuppressive mi

关键词： Hepatocellular carcinoma MicroRNA-142-3p ASH1L Immune evasion Tumor immune microenvironment Apoptosis