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Variation of freshwater components in the Canada Basin during 1967–2010

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Acta Oceanologica Sinica 2014年第6期33卷 40-45页

作者： PAN Hong chen min TONG Jinlu QIU Yusheng ZHENG minfang CAO Jianping College of Ocean and Earth Sciences Xiamen University State Key Laboratory of Marine Environmental Science Xiamen University

As a conservative tracer, oxygen isotopes in seawater are widely used for water mass analysis, along with temperature and salinity. In this study, seawater oxygen-18 datasets in the Canada Basin during 1967-2010 were obtained from the four cruises of the Chinese National Arctic Research Expedition （1999, 2003, 2008, and 2010） and the NASA database. Fractions of sea ice meltwater and river runoffwere determined from the salinity-5180 system. Our results showed that the river runoff decreased from the south to the north in the Canada Basin. The enhanced amount of river runoff observed in the southern Canada Basin may originate from the Mackenzie River, transported by the Beaufort Gyre. The river runoff component showed maximum fractions during 1967-1969, 1978-1979, 1984-1985, 1993-1994, and 2008-2010, indicating the refresh time of the river runoffwas 5.0-16.0 a in the Canada Basin. The temporal variation of the river runoffwas related to the change of the Arctic Oscillation （AO） index, suggesting the freshwater stored in the Canada Basin was affected by surface sea ice drift and water mass movement driven by atmospheric circulation.

关键词： Canada Basin freshwater river runoff sea ice meltwater oxygen isotope

Molecular Characterization and Virulence Genes of Aeromonas hydrophila Isolated from the Chinese Giant Salamander (Andrias davidianus)

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Asian Herpetological Research 2012年第4期3卷 303-309页

作者： Li WANG Yong WEI Guiping YUAN min DAI Xueliang chen Key Laboratory of Animal Genetics and Breeding of State Ethnic Affairs Commission & ministry of Education College of Life Science and TechnologySouthwest University for Nationalities Sichuan Academy of Animal Sciences Analytical & Testing Center Sichuan University School of Laboratory Medicine Chengdu Medical College Xiamen Sea World

The Chinese giant salamander(Andrias davidianus) is the largest living amphibian in the world. Aeromonas hydrophila strain L602 was isolated from A. davidianus. The 16S rDNA gene of this isolate was amplified using PCR,and the phylogenetic tree was constructed by the neighbor-joining method. Four virulence genes(aerA,aha1,hly and alt) of A. hydrophila were amplified by PCR and drug resistances were tested using Kirby-Bauer disk diffusion method. The results showed that the length of this 16S rDNA sequence was 1453 bp,which showed 99% homology with A. hydrophila. The GenBank accession number was JX155398. Phylogenetic analysis indicated it grouped together with A. hydrophila. Four virulence genes were all detected,indicating that strain L602 was highly virulent. This stain was resistant to four antibiotics(vibramycin,furazolidone,ampicillin and erythromycin),while it was insensitive to streptomycin. Furthermore,this strain was susceptible to six antibiotics(sulfafurazole,ciprofloxacin,penbritin,norfloxacin,florfenicol and enrofloxacin). This study will help to validate the classification and virulence of pathogenic bacteria in amphibians.

关键词： Chinese giant salamander 16S rDNA virulence gene drug resistance Aeromonas hydrophila

Efficient synthesis of functionalized 1,3-dihydroisobenzofurans from salicylaldehydes:Application to the synthesis of escitalopram

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Chinese Chemical Letters 2014年第4期25卷 549-552页

作者： Peng Wang Rui Zhang Jin Cai Jun-Qing chen min Ji School of Biological Science & Medical Engineering Southeast University School of Chemistry & Chemical Engineering Southeast University

An efficient synthesis of substituted 1,3-dihydroisobenzofurans is developed. In this novel route, oaroylbenzaldehydes, as key intermediates, can be obtained by lead tetraacetate oxidation of Naroylhydrazones of salicylaldehydes. The mild and general strategy enables the synthesis of various substituted 1,3-dihydroisobenzofurans in high yields. Moreover, this method can be applied to efficiently synthesize escitalopram.

关键词： Isobenzofuran Salicylaldehyde Efficient synthesis Escitalopram

一次复杂地形下边界层抬升型暖区暴雨对流触发条件和可预报性的数值研究

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大气科学 2024年第3期48卷 1095-1112页

作者：徐渊闵锦忠庄潇然王霄朱利剑江西省气象台南昌330096 南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心南京210044 江苏省气象台南京210008 凉山州气象局四川省凉山州615000 中国气象局上海台风研究所上海200030

长江中下游地区的暖区暴雨过程易受复杂下垫面强迫的影响,具有较大的预报不确定性,尤其是其中的对流触发过程。为探讨此类过程的触发条件及揭示其可预报性受限制程度,本文针对2020年6月23日一次复杂地形包裹下的长江中下游暖区暴雨展开... 详细信息

长江中下游地区的暖区暴雨过程易受复杂下垫面强迫的影响,具有较大的预报不确定性,尤其是其中的对流触发过程。为探讨此类过程的触发条件及揭示其可预报性受限制程度,本文针对2020年6月23日一次复杂地形包裹下的长江中下游暖区暴雨展开高分辨率的数值模拟和对流尺度集合模拟,通过Lagrange气块后向轨迹分析、去除地形和关闭热效应的敏感性试验以及集合敏感性分析等方法对此次过程的对流触发阶段展开分析。结果表明,此次过程被抬升气块的主要源地为1.5 km以下的边界层,仙霞岭和杉岭在正午时分因热力作用而驱动的出谷风是引发局地辐合抬升的动力源,高低层散度、湿位涡的垂直配置以及偶极型位涡异常对此次对流触发过程具有较好的指示意义。此外,该过程对前期近地面2 m高度处温度和模式底层视热源具有较高的敏感性,该结果证实下垫面强迫的精确刻画对于提升暖区暴雨的预报效果至关重要。逐步减小初始场误差的初值敏感性试验进一步表明,此次暖区对流过程的可预报性显著低于北边的锋面过程,表现为锋面对流的偏差总能量能随初始误差的缩小持续性降低,而暖区对流的偏差总能量曲线则仍能增长至与原水平相近,呈现出非线性辐合收缩特征。因此,对于天气尺度强迫显著的锋面对流,或可优先考虑通过加强资料同化能力等手段降低初始场误差来减小预报误差;但对于复杂地形下的暖区暴雨对流触发过程,则需要更加强调通过集合预报来捕捉其不确定性。

关键词：暖区暴雨对流触发复杂地形对流尺度集合模拟可预报性

Infant guinea pig retina model of glutamate toxicity and intervention of basic fibroblast growth factor

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Neural Regeneration Research 2011年第7期6卷 534-541页

作者： Yunzhi Shi Lihua Wei mingshan Song min chen Changqing Du Baoliang Sun Department of Histology and Embryology Taishan Medical College Taian 271000 Shandong Province China Department of Urology Taian Central Hospital Taian 271000 Shandong Province China Department of Foreign Language Taishan Medical College Taian 271000 Shandong Province China Key Laboratory of Cerebral Microcirculation at the Universities of shandong Department of Neurology Affiliated Hospital of Taishan MedicalCollege Taian 271000 Shandong Province China

Impaired vision with oligemic ophthalmopathy is a result of excitotoxicity caused by excitatory amino acids, resulting in pathological changes, such as loss of retinal neurons and in particular retinal ganglionic cells. The present study utilized infant guinea pigs, aged 45-50 days, to establish injury models via intraperitoneal injection of fixed sodium glutamate doses. Results from hematoxylin- eosin staining revealed significantly reduced retinal ganglionic cell numbers and retinal damage at 10 days after 7 consecutive days of 3 g/kg sodium glutamate treatment; these animals served as the injury model group. In addition, models of moderate injury （glutamate 3 g/kg daily, for 7 consecutive days） were intraperitoneally pretreated with basic fibroblast growth factor （800 U/kg daily）. Immunohistochemistry results confirmed reduced anti-apoptotic gene bcl-2 expression in the ganglion cell layer of glutamate-injured guinea pigs. Expression of the pro-apoptotic gene caspase-3 was increased in the ganglion cell layer and inner plexiform layer. Somatostatin expression was primarily distributed in the ganglion cell layer and inner nuclear layer. Expression of the presynaptic element synaptophysin was weak. However, following basic fibroblast growth factor injection, expressions of the above-described bioactive molecules were reversed, which suggested that basic fibroblast growth factor exerted protective effects on sodium glutamate-induced retinal injury in infant guinea pigs by regulating expression of synaptophysin, somatostatin, Bcl-2, and caspase-3.

关键词： synaptophysin somatostatin apoptosis-related genes basic fibroblast growth factor glutamate retina

Study on the Microstructure and Dielectric Properties of Barium Strontium Titanate Thin Films Prepared by Sol-gel Method

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Chinese Journal of Aeronautics 2006年第B12期19卷 167-172页

作者： shan Lian-wei ZHANG Xian-you DONG Li-min WU Ze HAN Zhi-dong FU Xing-hua HOU Wen-ping Department of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China Department of Materials Science and Engineering Jinan University Jinan 250022 China

Sr05Ba0.5-xBixTiO3 （BST） thin films were fabricated on a Pt/SiO2/Si substrate by the sol-gel method. Then follows an investigation of the influeoces of bismuth （Bi） on the microstructures and the dielectric properties of Sr0.5Ba0.5-xBixTiO3 （BST） thin films. The microstructures of the BST thin films were examined by the XRD and the TEM techniques. Tetragonal perovskite crystal grains were observed in BST thin films. Increasing Bi^3＋ doping ration in BST will lead to decrease of the grain size. It is found that Bi^3＋ doping decreases the dielectric loss and improves the frequency dispersion of the BST thin films. Not only is compressed the peak of temperature-dependence of dielectric constant of Bi^3＋-doped BST thin films but also moves into the low-temperature region. Moreover, the average Curie tem- perature decreases gradually with the Bi^3＋ contents increasing.

关键词： BST thin films Bi doping characteristic microstructure

Air Quality Prediction Based on Kohonen Clustering and ReliefF Feature Selection

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Computers, Materials & Continua 2020年第8期64卷 1039-1049页

作者： Bolun chen Guochang Zhu min Ji Yongtao Yu Jianyang Zhao Wei Liu College of Computer Engineering Huaiyin Institute of TechnologyHuaian233003China Department of Physics University of FribourgFribourgCH-1700Switzerland College of Information Engineering Yangzhou UniversityYangzhou225009China

Air quality prediction is an important part of environmental *** accuracy of the air quality prediction also affects the planning of people’s outdoor *** to mine effective information from historical data of air pollution and reduce unimportant factors to predict the law of pollution change is of great significance for pollution prevention,pollution control and pollution early *** this paper,we take into account that there are different trends in air pollutants and that different climatic factors have different effects on air ***,the data of air pollutants in different cities are collected by a sliding window technology,and the data of different cities in the sliding window are clustered by Kohonen method to find the same tends in air *** this basis,combined with the weather data,we use the ReliefF method to extract the characteristics of climate factors that helpful for ***,different types of air pollutants and corresponding extracted the characteristics of climate factors are used to train different sub *** experimental results of different algorithms with different air pollutants show that this method not only improves the accuracy of air quality prediction,but also improves the operation efficiency.

关键词： Air quality prediction Kohonen clustering ReliefF feature selection

南瓜胡萝卜番茄皮渣复合发酵饮料的工艺优化及功能特性的研究

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食品安全质量检测学报 2024年第4期15卷 139-147页

作者：于梅郭欣奕单子玉李胜平高雪宋健平王雨萌陈庆敏山东农业工程学院食品科学与工程学院济南250100

目的优化南瓜胡萝卜番茄皮渣复合发酵饮料的加工工艺,并探究发酵前后饮料的功能特性。方法以南瓜、胡萝卜和番茄皮渣为主要原料,利用嗜酸乳杆菌进行发酵,以感官评分和总酸含量设置加权总分为指标,通过单因素和正交实验,确定最佳发酵工... 详细信息

目的优化南瓜胡萝卜番茄皮渣复合发酵饮料的加工工艺,并探究发酵前后饮料的功能特性。方法以南瓜、胡萝卜和番茄皮渣为主要原料,利用嗜酸乳杆菌进行发酵,以感官评分和总酸含量设置加权总分为指标,通过单因素和正交实验,确定最佳发酵工艺条件。在此基础上进行发酵前后抗氧化活性和辅助降血脂功效的对比。结果最佳发酵工艺条件为:料水比1:35(g:mL)、糖添加量15%、菌添加量0.10%、发酵时间5 d。该条件下得到的发酵饮料酸甜可口,蔬菜与发酵香气协调柔和,色泽呈鲜艳的粉红色,质地均匀,无沉淀,感官评分为9.37分,总酸含量为(2.24±0.29)g/L,总分为7.23,可溶性固形物含量为(16.43±0.53)%,总糖含量为(70.94±0.41)mg/mL,微生物指标符合国家标准要求。多酚含量为(865.00±0.36)μg/mL、黄酮含量为(647.00±0.44)μg/mL、三萜皂苷含量(3577.00±0.49)μg/mL,分别为发酵前的1.50倍、2.89倍、1.54倍。羟基自由基、超氧阴离子自由基、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基、2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)ammonium salt,ABTS]阳离子自由基清除率分别为(81.34±0.41)%、(56.06±0.72)%、(87.26±0.63)%、(82.75±0.29)%,与发酵前相比自由基清除率分别提高了29.82%、19.39%、40.38%、39.40%。甘氨胆酸钠、牛磺胆酸钠、胆酸钠吸附率分别为(69.95±0.37)%、(71.61±0.58)%、(61.23±0.62)%,与发酵前相比分别提高了20.21%、19.75%、14.50%。结论南瓜胡萝卜番茄皮渣复合发酵饮料具有更强的抗氧化活性和辅助降血脂功效,为我国果蔬皮渣废弃物资源综合开发利用提供参考。

关键词：南瓜胡萝卜番茄皮渣嗜酸乳杆菌抗氧化辅助降血脂

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非线性能量阱最优参数的变化规律研究

天津理工大学学报 2024年第1期40卷 133-139页

作者：李建玲陈建恩孙敏刘小伟天津理工大学天津市先进机电系统设计与智能控制重点实验室天津300384 天津理工大学机电工程国家级实验教学示范中心天津300384 天津城建大学理学院天津300384

利用粒子群优化算法(particle swarm optimization,PSO)研究了单自由度和两自由度非线性能量阱(nonlinear energy sink,NES)的最优参数随冲击载荷的变化规律。在仅改变刚度和同时改变阻尼与刚度情况下对NES的最优吸振效能和最优参数进... 详细信息

利用粒子群优化算法(particle swarm optimization,PSO)研究了单自由度和两自由度非线性能量阱(nonlinear energy sink,NES)的最优参数随冲击载荷的变化规律。在仅改变刚度和同时改变阻尼与刚度情况下对NES的最优吸振效能和最优参数进行对比分析。结果表明,优化后的两自由度NES的吸振效能略优于单自由度NES。随着冲击载荷的增大,两种NES的最优刚度均逐渐减小,最优阻尼均逐渐增大。若考虑被动式装置,两自由度NES的吸振效能显然优于单自由度NES。若加入控制,使NES始终处于最优参数,两自由度NES的效能优势非常小,且其控制参数较多。

关键词：非线性能量阱(NES) 吸振效能最优参数粒子群优化算法(PSO)