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Impacts of Climate Change on Forest Ecosystems in Northeast China

Advances in Climate Change Research 2013年第4期4卷 230-241页

作者： WANG Xiao-Ying zhao chun-yu JIA Qing-yu Institute of Atmospheric Environment of China China Meteorological Administration Liaoning Provincial Meteorological Information Center

This paper reviews the studies and research on climate change impacts on the forest ecosystems in Northeast China. The results show that in the context of global and regional warming, the growing season of coniferous forests has been increasing at an average rate of 3.9 d per decade. Regional warming favors the growth of temperate broad-leaved forests and has a detrimental effect on the growth of boreal coniferous forests. Over the past hundred years, the forest edge of the cool temperate zone in the southern Daxing＇anling region has retreated 140 km northward. From 1896 to 1986, the northern boundary of broad-leaved forests in Heilongjiang province has extended northwestward about 290 km. Future climatic changes （until 2060） may lead to the northern deciduous needle forests moving out of China＇s territory altogether. The occurrence cycles of pests and diseases have shortened; their distribution ranges have expanded. The life cycle of tent caterpillars （Malacosoma neustria testacea Motschulsky） has shortened from 14-15 years in the past to 8-10 years now. The pine caterpillar （Dendrolimus tabulaeformis Tsai et Liu）, which has spread within western Liaoning province and the nearby areas, can now be found in the north and west. Lightning fires in the Daxing＇anling region have significantly increased since 1987, and August has become the month when lightning fires occur most frequently. Overall, the net primary productivity （NPP） of forest in Northeast China has increased. The NPP in 1981 was around 0.27 Pg C, and increased to approximately 0.40 Pg C in 2002. With the current climate, the broad-leaved Korean pine forest ecosystem acts as a carbon sink, with a carbon sink capacity of 2.7 Mg C hm-2. Although the carbon sink capacity of the forest ecosystems in Northeast China has been weakened since 2003, the total carbon absorption will still increase. The forest ecosystems in Northeast China are likely to remain a significant carbon sink, and will play a positive role

关键词： Northeast China forest ecosystem climate change

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Intermittent abdominal pain accompanied by defecation difficulties caused by Chilaiditi syndrome: A case report

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World Journal of Clinical Cases 2018年第15期6卷 1042-1046页

作者： Xia-Gang Luo Jing Wang Wu-Lin Wang chun-zhao yu Department of General Surgery the Second Affiliated Hospital of Nanjing Medical University

We report a case of intermittent lower abdominal pain and distension accompanied by defecation difficulties for 3 years due to Chilaiditi syndrome in a 59-yearold male. Before admission to our hospital, the patient had undergone gastroscopy, which showed gastritis and duodenitis, and colonoscopy, which showed cecum deformation and cicatricial changes of the mucous membrane in the colon hepatic flexure. A computed tomography(CT) scan of the abdomen at our hospital confirmed right hepatic atrophy and interposition of the colon. Moreover, CT simulation endoscopy identified cystic dilatation in the colon hepatic flexure with the widest diameter of 8.2 cm. The patient was diagnosed with Chilaiditi syndrome. As the patient was unable to endure his defecation difficulties, he underwent a laparoscope-assisted right hemicolectomy. The patient had a good recovery. During the follow-up period of 9 mo, the patient remained symptom-free.

关键词： Abdominal pain Diagnosis Management Laparoscope-assisted right hemicolectomy Chilaiditi sign Chilaiditi syndrome Case report

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Giant ventral hernia simultaneously containing the spleen, a portion of the pancreas and the left hepatic lobe: A case report

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World Journal of Clinical Cases 2020年第9期8卷 1721-1728页

作者： Xia-Gang Luo Chen Lu Wu-Lin Wang Fei Zhou chun-zhao yu Department of General Surgery the Second Affiliated Hospital of Nanjing Medical UniversityNanjing 2l0011Jiangsu ProvinceChina

BACKGROUND Ventral hernia,also known as incisional hernia,is a common complication of previous *** contents of ventral hernia may include omentum,preperitoneal fat,small intestine or ***,ventral hernia with protrusion of more than two parenchymal organs simultaneously is extremely rare,and its repair is very complex and *** should make a comprehensive assessment based on their own experience and the individual characteristics of the *** addition,psychological therapy should be emphasized in the whole treatment *** SUMMARY We report a rare case of asymptomatic giant ventral hernia for 15 years in a 21-year-old *** patient underwent umbilical hernia repair at the age of 1 *** 5 years later,ventral hernia recurred and repair with Mesh was performed,but the operation failed due to postoperative infection,and a huge mass appeared in the left abdominal *** mass increased gradually with the development and maturity of the *** tomography scan demonstrated that the patient's total spleen,part of the pancreas and left lobe of the liver were simultaneously herniated through the abdominal incisional *** the patient was unable to endure the inconvenience of life and the potential risk of spleen or liver rupture,she underwent a ventral hernia repair with Mesh at our *** operation was successful and the patient had a good *** a 3-mo follow-up,the patient remained asymptomatic and the appearance of the surgical incision was greatly *** Ventral hernia is a common complication of abdominal *** hernia with protrusion of more than two parenchymal organs simultaneously is extremely *** should pay attention to the psychological treatment while restoring the abdominal physiological function in ventral hernia patients.

关键词： Giant ventral hernia Spleen Pancreas Liver Mesh Case report

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Synthesis and Characterization of NASICON Nanoparticles by Sol-gel Method

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Chemical Research in Chinese Universities 2009年第1期25卷 13-16页

作者： WANG Biao LIANG Xi-shuang LIU Feng-min ZHONG Tie-gang zhao chun LU Ge-yu QUAN Bao-fu State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 P. R. China

Na superionic conductor（NASICON） nanoparticles were synthesized by a modified sol-gel method and sintered at a temperature range of 800--1000℃. The performance of the samples was characterized by the analysis methods of X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, and transmission electron microscopy（TEM） as well as conductivity measurement. Compared with those sintered at other temperatures, the NASICON material sintered at 900 ℃ had the best crystalline structure and higher conductivity.

关键词： Na superionic conductor(NASICON) Nanoparticles Sol-gel method

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Changes in Climatic Factors and Extreme Climate Events in Northeast China during 1961-2010

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Advances in Climate Change Research 2013年第2期4卷 92-102页

作者： zhao chun-yu WANG Ying ZHOU Xiao-yu CUI Yan LIU yu-Lian SHI Da-Ming yu Hong-Min LIU yu-Ying Regional Climate Center of Shenyang Liaoning Meteorological Service Climate Center of Heilongjiang Heilongjiang Meteorological Service Climate Center of Jilin Jilin Meteorological Service

This study focuses on examining the characteristics of climate factors and extreme climate events in Northeast China during 1961- 2010 by using daily data from 104 stations, including surface air temperature, precipitation, wind speed, sunshine duration, and snow depth. Results show that annual mean temperature increased at a significant rate of 0.35℃ per decade, most notably in the Lesser Khingan Mountains and in winter. Annual rainfall had no obvious linear trend, while rainy days had a significant decreasing trend. So, the rain intensity increased. High-temperature days had a weak increasing trend, and low-temperature days and cold wave showed significant decreasing trends with rates of 3.9 d per decade and -0.64 times per decade, respectively. Frequency and spatial scope of low-temperature hazard reduced significantly. Warm days and warm nights significantly increased at 1.0 and 2.4 d per decade, while cold days and cold nights decreased significantly at -1.8 and -4.1 d per decade, respectively. The nighttime warming rate was much higher than that for daytime, indicating that nighttime warming had a greater contribution to the overall warming trend than daytime warming. The annual mean wind speed, gale days, and sunshine duration had significant decreasing trends at rates of-0.21 m s-1 per decade, -4.0 d per decade and -43.3 h per decade, respectively. The snow cover onset dates postponed at a rate of 1.2 d per decade, and the snow cover end date advanced at 1.5 d per decade, which leads to shorter snow cover duration by -2.7 d per decade. Meanwhile, the maximum snow depth decreased at -0.52 cm per decade. In addition, the snow cover duration shows a higher correlation with precipitation than with temperature, which suggests that precipitation plays a more important role in maintaining snow cover duration than temperature.

关键词： climatic factors extreme climate events climate change Northeast China

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Relationship Between Hyperspectral Parameters and Physiological and Biochemical Indexes of Flue-Cured Tobacco Leaves

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Agricultural Sciences in China 2007年第6期6卷 665-672页

作者： LI Xiang-yang LIU Guo-shun YANG Yong-feng zhao chun-hua yu Qi-wei SONG Shi-xu National Tobacco Cultivation and Physiology and Biochemistry Research Center of Henan Agricultural University Zhengzhou 450002P.R. China

The experiment was set up for examining the physiological and biological indexes quickly and exactly, for obtaining information of tobacco-field fertilizing and tobacco growing. The ASD Field spec FR 2500 was used to measure spectra reflectance of flue-cured tobacco and the relationship between hyperspectral parameters and biochemical contents （total nitrogen, chlorophyll, carotenoid）, and physiological indexes （fresh weight, dry weight, moisture content） of flue-cured tobacco leaves was studied by correlation and stepwise regression statistic methods at different nitrogen and potassium levels. The results indicated that the spectra curves of different treatments had obvious rules and great diversities. There were high correlations between different types of spectra parameters and ten physiological and biochemical indexes of flue-cured tobacco leaves. Hyperspectral characteristic variables of ten physiological and biochemical indexes were found through stepwise regression, and SDr/SDb was the characteristic variable closest to seven biochemical contents. Simultaneously, the R2 and regression coefficient of equations reached 0.05 significant level and the equations had good estimating effects through the examination of other samples. Accordingly, this study suggested that the ten physiological and biochemical indexes could be estimated quickly by the estimating models, at the same time nitrogen-potassium fertilization and growth condition of flue-cured tobacco could be inspected.

关键词： flue-cured tobacco leaves hyperspectral parameters physiological and biochemical indexes

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机床动态切削力测定试验与时间序列模型预测

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东北大学学报（自然科学版） 2019年第4期40卷 521-525,530页

作者：张宝赵春雨闻邦椿东北大学机械工程与自动化学院辽宁沈阳110819

为获取动态切削力,在数控机床ETC1625P上对12Cr18Ni9回转件进行外圆切削试验.利用信号实时采集系统获取刀具在切削平面内两个正交方向运动的位置信息,同时将KISTLER传感器安装在机床刀头上,测得加工过程中三个切削方向的实时切削力.试... 详细信息

为获取动态切削力,在数控机床ETC1625P上对12Cr18Ni9回转件进行外圆切削试验.利用信号实时采集系统获取刀具在切削平面内两个正交方向运动的位置信息,同时将KISTLER传感器安装在机床刀头上,测得加工过程中三个切削方向的实时切削力.试验数据表明切削力在进给方向随位移而波动性变化.为研究切削力与切削参数之间的复杂非线性关系,通过时间序列分析建模,实现对动态切削力的预测.对切削力误差进行分析,得到的预测精度符合要求.

关键词：机床切削试验动态切削力时间序列分析预测建模

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双质体自同步振动系统的动力学耦合特性分析

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振动工程学报 2016年第3期29卷 521-531页

作者：贺斌赵春雨闻邦椿东北大学机械工程与自动化学院辽宁沈阳110819

利用改进小参数平均法,推导出了平面运动双质体振动系统中两偏心转子的无量纲耦合方程,并依据其零解的存在及稳定性,得出了实现同步与同步稳定性运行的条件,给出了系统负载系数及同步能力系数定义。通过数值分析,讨论了系统动力学参数... 详细信息

利用改进小参数平均法,推导出了平面运动双质体振动系统中两偏心转子的无量纲耦合方程,并依据其零解的存在及稳定性,得出了实现同步与同步稳定性运行的条件,给出了系统负载系数及同步能力系数定义。通过数值分析,讨论了系统动力学参数对耦合同步特性的影响,得到了双偏心转子自同步的稳定运行的参数区间。结果表明:随着系统动力学参数的变化,同步极值点既可能是负载系数的极小值点,也可能是负载系数的极大值点。其原因是由于双质体的耦合作用,来自于机体运动的同步力矩,在一定参数范围内驱动两个偏心转子相位差向负载系数最大值点趋近;而在此区域以外,驱动两偏心转子相位差向负载系数极最小值点趋近。通过数值仿真,验证了耦合分析结果的正确。

关键词：双质体振动系统自同步稳定性耦合动力学

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三质体振动机动力学参数对其性能的影响分析

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振动与冲击 2015年第12期34卷 70-78页

作者：赵春雨赵乾斌贺斌闻邦椿东北大学机械工程与自动化学院沈阳110819

提出了工作质体无量纲特征幅值、特征幅值放大倍数、最大参振物料系数、隔振架与基础之间的力传递系数、同步能力系数和临界隔振频率比作为描述三质体振动机的性能指标。通过数值计算,研究了系统动力学参数对振动机各性能指标的影响规... 详细信息

提出了工作质体无量纲特征幅值、特征幅值放大倍数、最大参振物料系数、隔振架与基础之间的力传递系数、同步能力系数和临界隔振频率比作为描述三质体振动机的性能指标。通过数值计算,研究了系统动力学参数对振动机各性能指标的影响规律。当工作质体工作于超共振态时,特征幅值和力传递系数随隔振频率增加而减小。当隔振频率比相同且大于临界隔振频率比时,随工作质体与隔振质体质量比的减小,初始特征幅值和最大力传递系数增大,特征幅值放大倍数和最大参振物料系数略有减小,即较小的工作质体与隔振质体质量比,有利于提高振动机的综合性能指标。振动激励角越小,系统同步能力系数越大。当支撑刚体作为物料箱时,同步能力系数随工作质体与激振器安装刚体的质量比的增加而增大。系统结构能够满足两激振器自同步运行的稳定性要求,计算机仿真结果验证了理论研究的正确性。

关键词：振动系统隔振自同步稳定性

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Effects of metoprolol treatment on a disintegrin metalloproteinase expression and extracellular matrix remodeling after myocardial infarction in rats

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Chinese Medical Journal 2007年第17期120卷 1549-1552页

作者： zhao Juan QU Xiu-fen zhao chun-yu CAO Feng-lin ZHOU Tao LI Wei-min HUANG Yong-lin Department of Cardiology First Affiliated Hospital of HarbinMedical University Harbin 150001 China Department of Neurological Rehabilitation China RehabilitationResearch Center Beijing 100068 China Laboratory of Cardiology First Affiliated Hospital of HarbinMedical University Harbin 150001 China Da＇an Living Limited Company Sun Yat-sen UniversityGuangzhou 510070 China

Ventricular remodeling （VR） after myocardial infarction （MI） makes a full impact on left ventricular dilation and dysfunction, severe arrhythmias and even sudden death. Thus it is very interesting and instructive to study the underlying regulatory mechanism for VR. Recently, evidenceI suggests that tumor necrosis factor-α （TNF-α） activity can independently influence VR, and aggravate myocardial dysfunction and cell death in the ventricle. The activation of pro-TNF〈t is adjusted by a disintegrin metalloproteinase （ADAM） 10 and ADAM17, the latter might take part in extracellular matrix （ECM） modulation in the borderline region of cardiac infarction.2 However, little is known about the relationship between ADAMsl0, 17 expressions and TNF-α activity in the process of VR after MI. The present study tested the hypothesis in rats that the interaction between ADAMsl0, 17 expressions and TNF-α activity was a contributory mechanism for VR of the healing myocardium, and metoprolol treatment might ameliorate VR inhibiting the mechanism.

关键词： myocardial infarction a disintegrin metalloproteinase extracellular matrix ventricular remodeling metoprolol

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