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Mapping Deciduous Broad-leaved Forested Swamps Using ALOS/Palsar Data

Chinese Geographical Science 2016年第3期26卷 352-365页

作者： BIAN Hongfeng YAN Tingting zhang zhengxiang HE Chunguang SHENG Lianxi State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration School of Environment Northeast Normal University School of Geographical Sciences Northeast Normal University

Accurate, updated information on the distribution of wetlands is essential for estimating net fluxes of greenhouse gases and for effectively protecting and managing wetlands. Because of their complex community structure and rich surface vegetation, deciduous broad-leaved forested swamps are considered to be one of the most difficult types of wetland to classify. In this research, with the support of remote sensing and geographic information system, multi-temporal radar images L-Palsar were used initially to extract the forest hydrological layer and phenology phase change layer as two variables through image analysis. Second, based on the environmental characteristics of forested swamps, three decision tree classifiers derived from the two variables were constructed to explore effective methods to identify deciduous broad-leaved forested swamps. Third, this study focused on analyzing the classification process between flat-forests, which are the most severely disturbed elements, and forested swamps. Finally, the application of the decision tree model will be discussed. The results showed that: 1) L-HH band(a L band with wavelength of 0–235 m in HH polarization mode; HH means Synthetic Aperture Radars transmit pulses in horizontal polarization and receive in horizontal polarization) in the leaf-off season is shown to be capable of detecting hydrologic conditions beneath the forest; 2) the accuracy of the classification(forested swamp and forest plat) was 81.5% based on hydrologic features, and 83.5% was achieved by combining hydrologic features and phenology response features, which indicated that hydrological characteristics under the forest played a key role. The HHOJ(refers to the band created by the subtraction with HH band in October and HH band in July) achieved by multi-temporal radar images did improve the classification accuracy, but not significantly, and more leaf-off radar images may be more efficient than multi-seasonal radar images for inland forested sw

关键词： forested swamp Palsar radar images forest hydrological characteristics multi-temporal technique decision tree classifier

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Nuclear events during conjugation in the poorly studied model ciliate Paramecium jenningsi

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Water Biology and Security 2023年第4期2卷 69-77页

作者： Xue zhang Ruitao Gong Yaohan Jiang Xiaoteng Lu Chenyin Wu Lihan Wang Hongwei Ma zhengxiang zhang Weibo Song Khaled A.S.Al-Rasheid Adriana Vallesi Feng Gao Institute of Evolution&Marine Biodiversity Ocean University of ChinaQingdao266003China Department of Biology Shenzhen MSU-BIT UniversityShenzhen518172China College of Fisheries Ocean University of ChinaQingdao266003China Laoshan Laboratory Qingdao266237China Zoology Department College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia Laboratory of Eukaryotic Microbiology and Animal Biology University of CamerinoCamerino62032Italy

Ciliated protists are highly differentiated unicellular eukaryotes that possess special sexual processes(conjugation and autogamy)that rely on their unique nuclear dimorphism,i.e.,the presence of both a germline micronucleus(MIC)and a somatic macronucleus(MAC)in a single *** sexual processes show a high diversity in different *** better understand the differentiation and evolution of sexual processes in closely related species,we investigated the nuclear events during conjugation in Paramecium jenningsi strain GZ,a poorly studied close relative of the well-known *** *** main results include:(1)the conjugation process takes about 48 h,including three prezygotic divisions(meiosis I,II,and mitosis)and three postzygotic divisions;(2)the MICs are dominated by the“parachute”phase at the prophase of meiosis I;(3)after meiosis II,a variable number of nuclei undergo the third prezygotic division,and the two products near the paroral cone become the genetically identical migratory and stationary pronuclei;(4)the synkaryon divides three times to form the MIC and the MAC anlagen,but only one nuclear product of the first postzygotic division completes the next two divisions;and(5)an extra cell division is required to complete the last step of conjugation,during which two MIC anlagen undergo mitotic division while two MAC anlagen are distributed between the daughter cells without *** comparison of the nuclear events during conjugation in representatives of the class Oligohymenophorea reveals that usually there are three prezygotic divisions and a variable number of postzygotic ***,the number of selected and differentiated nuclei after each division differs among *** study provided a new model ciliate for further investigations of nuclear selection and differentiation as well as nuclear morphology during meiosis.

关键词： Ciliates Conjugation Cytology Life cycle Nuclear events Paramecium jenningsi

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High performance liquid chromatography tandem quadrupole-time of flight mass for non-targeted compound identification in complex matrices:art of the state

High performance liquid chromatography tandem quadrupole-tim...

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全国生物医药色谱及相关技术学术交流会（2012）

作者： Tao BO,Xiaorong RAN,zhengxiang zhang,Wei CHEN Agilent Technologies

A quantitative answer cannot exist in analysis without a qualitative component to give enough confidence that the result meets the analytical needs,especially for screening the non-targeted compounds in complex ***-time of flight mass spectrometry with ultra-high mass resolution and MS/MS capability plays a crucial role because the structural information including the accurate mass of both precursor and product ions can be *** this study,as shown in Figure 1,a full workflow of screening unknown compounds with diverse structures（such as toxic and illegal drugs,natural products,pharmaceutical impurities,etc.） in a series of real samples（including herbal medicines,food,biological matrices and pharmaceutical preparations） was exhibited based on the HPLC ＆ CE-QTOF,involving database establishment based on accurate mass,data processing（Mass Feature Extract,MFE）,database ＆ library search and MS/MS *** key points and outstanding features by HPLC-QTOF technology for the unknown compound confirmation were discussed,with respect to the influence of HPLC conditions on QTOF detection,QTOF parameter optimization,sample preparation and MS/MS fragmentation *** quantitative analysis by LC-QTOF（with the 20 ppm EIC extracted window） was also investigated in bios-samples with regards to high-reliable confirmation and good sensitivity resulting from accurate mass and high-resolution.

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Study on Variation of Fitting Goodness of Relation Between Earthquake Frequency and Magnitude before Moderately Strong Earthquakes (Ms≥5.0)

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Earthquake Research in China 1996年第4期10卷 20-28页

作者： Li Zhixiong,zhang Guomin,Fu zhengxiang,and zhang YongxianState Seismological Bureau,Beijing 100036,China Center for Analysis and Prediction,SSB,Beijing 100036,China

In this paper,characteristics of spatial and temporal variation of linear fitting goodness before some moderately strong earthquakes(Ms≥5.0)in the eastern part of China(east of longitude 180)are studied according to the famous Gutenberg-Richter’s relation expressed as lgN=a-bM,by using the moderate and small events that occurred in and around the source *** results show that the linear goodness of fitting varies abnormally prior to these moderately strong *** the early stage of the earthquake preparatory process,distribution of the energy released through small events in and around the source area is isostatic and the fitting goodness approximates 1,while the distribution of the energy turns to be isostatic before moderately strong earthquakes,leading to the obvious decrease of the linear goodness of *** phenomenon could be a medium term anomaly and a medium term criterion for moderately strong earthquake prediction.

关键词： Relation between earthquake frequency and magnitude Linear goodness of fitting Medium term criterion for moderately strong earthquakes

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趣味教学法在小学数学课堂中的应用策略

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当代家庭教育 2020年第35期 4-5页

作者：张正香甘肃省白银市白银区第五小学

趣味教学法在小学数学课堂中的应用有其重要的意义,教师可以适时采用合理有效的趣味教学方法和手段,激发和调动小学生的数学思考和探究兴趣,集中学生探索数学知识的注意力,体会到趣味教学法的"玩中学"的乐趣,培养学生良好的逻辑能力和... 详细信息

趣味教学法在小学数学课堂中的应用有其重要的意义,教师可以适时采用合理有效的趣味教学方法和手段,激发和调动小学生的数学思考和探究兴趣,集中学生探索数学知识的注意力,体会到趣味教学法的"玩中学"的乐趣,培养学生良好的逻辑能力和思维品质,将学生引入到深层的数学思考之中,透彻体悟小学数学知识内容。

关键词：趣味教学法小学数学课堂

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试论价值的本质

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南京广播电视大学学报 2009年第4期 99-102页

作者：张正翔无锡广播电视大学江苏无锡214011

价值理论是当前理论和实践的重大问题。劳动决定价值的观点难以正确说明当前重大的现实问题;而非劳动因素如何决定价值,特别是如何使价值增值尚无合理的解释。从价值本质理论看:价值的本质是人们之间社会关系,价值决定的基本要素在形式... 详细信息

价值理论是当前理论和实践的重大问题。劳动决定价值的观点难以正确说明当前重大的现实问题;而非劳动因素如何决定价值,特别是如何使价值增值尚无合理的解释。从价值本质理论看:价值的本质是人们之间社会关系,价值决定的基本要素在形式上表现为劳动和资源;价值的形成和增值是多种因素作用的结果,而且是一个动态的过程,体现了人们之间社会关系的复杂性。

关键词：价值本质劳动自然资源

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马克思商品拜物教理论的精髓及意义

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南京广播电视大学学报 2010年第3期 24-27页

作者：张正翔无锡城市职业学院江苏无锡214011

在商品拜物教理论中,马克思价值理论的基本思想、基本观点、基本方法在这里得到集中的体现,其中突出的成果是揭示了价值的本质,这对深入研究、发展价值理论以及现实的经济建设都有指导意义。

关键词：拜物教价值的本质货币的形式

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瘦肉型后备母猪饲养管理技术要点

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贵州畜牧兽医 2011年第1期35卷 55-56页

作者：张正相贵州省贵阳市花溪区农业局贵州贵阳550025

在当今中国规模化生猪养殖场,绝大部分都是饲养大约克、长白、杜洛克或其杂交的二元、三元等瘦肉型猪,饲养种猪的场都离不开猪群更新,猪群更新就是从后备母猪群中选择一定数量的后备母猪进入基础母猪群,从而达到猪群的生产平衡。猪场基... 详细信息

在当今中国规模化生猪养殖场,绝大部分都是饲养大约克、长白、杜洛克或其杂交的二元、三元等瘦肉型猪,饲养种猪的场都离不开猪群更新,猪群更新就是从后备母猪群中选择一定数量的后备母猪进入基础母猪群,从而达到猪群的生产平衡。猪场基础母猪群年更新率一般在30％以上，这一数字决定了后备母猪培育在生猪生产中的重要意义，

关键词：母猪饲养瘦肉型猪管理技术要点后备母猪生猪生产母猪群生产平衡养殖场

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从地租理论来看马克思的劳动价值论

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广西广播电视大学学报 2005年第1期16卷 55-58页

作者：张正翔无锡市广播电视大学江苏无锡214021

地租问题比较特殊,在这领域的研究中,很难象其它领域一样,高度抽象掉非劳动因素,仅用劳动说明地租的来源。马克思在研究中,并不否认自然资源、稀缺、市场状况、所有权、垄断在价值决定中的作用。在地租理论中,马克思再次引用“社会总劳... 详细信息

地租问题比较特殊,在这领域的研究中,很难象其它领域一样,高度抽象掉非劳动因素,仅用劳动说明地租的来源。马克思在研究中,并不否认自然资源、稀缺、市场状况、所有权、垄断在价值决定中的作用。在地租理论中,马克思再次引用“社会总劳动”的概念,是马克思劳动决定价值走向“价值的本质是人们之间的社会关系”理论的起点。这为我们完善和发展马克思的价值理论提供支点。

关键词：地租来源本质社会总劳动

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CSP板卷边部缺陷的研究

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河南冶金 2006年第B9期14卷 114-118,120页

作者：张正祥涟源钢铁集团有限公司

针对涟钢CSP板卷存在的主要质量问题———板卷边部缺陷,统计分析大生产数据,现场跟踪试验,以及实验室验证,研究查找出CSP板卷边部缺陷的主要影响因素,通过采取相应控制与改善措施,获得了良好效果。

关键词： CSP 板卷质量表面缺陷

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