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Speckle suppression in synthetic aperture radar ocean internal solitary wave images with curvelet transform

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Acta Oceanologica Sinica 2016年第9期35卷 13-21页

作者： ZHA Guozhena he Qingyou GUAN Changlonga SUN Jian he mingxia College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China Ocean Remote Sensing Institute Ocean University of ChinaQingdao 266100China

This paper proposes a speckle-suppression method for ocean internal solitary wave（ISW） synthetic aperture radar（SAR） images by using the curvelet *** band-shaped signatures of ocean ISWs in SAR images show obvious scale and directional *** curvelet transform possesses a very high scale and directional ***,the curvelet transform is very efficient in analyzing wave signals in SAR images.A noisy ocean ISW SAR image can be decomposed at different scales,directions,and positions using the curvelet *** information of the ISWs is centralized in the curvelet coefficients of certain directions under certain scales,whereas the speckle noise is distributed in every scale and *** manipulating the curvelet coefficients,the signals of the ISWs can be extracted from the noisy SAR ***,the speckle noise is suppressed and the ISW feature is enhanced by adding the signals of the ISWs back to the original SAR *** demonstrate the effectiveness of this method.

关键词： curvelet transform internal solitary wave remote sensing speckle noise synthetic aperture radar

Performance evaluation of operational atmospheric correction algorithms over the East China Seas

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Chinese Journal of Oceanology and Limnology 2017年第1期35卷 1-22页

作者： he Shuangyan[l,2,3] he mingxia FISCheR Jurgen Ocean Remote Sensing Institute Ocean University of China Qingdao 266003 China Institute for Space Sciences Freie Universitdt Berlin Berlin D-12165 Germany Ocean College Zhejiang University Hangzhou 310058 China

To acquire high-quality operational data products for Chinese in-orbit and scheduled ocean color sensors, the performances of two operational atmospheric correction(AC) algorithms(ESA MEGS 7.4.1 and NASA Sea DAS 6.1) were evaluated over the East China Seas(ECS) using MERIS data. The spectral remote sensing reflectance R_(rs)(λ), aerosol optical thickness(AOT), and ?ngstr?m exponent(α) retrieved using the two algorithms were validated using in situ measurements obtained between May 2002 and October 2009. Match-ups of R_(rs), AOT, and α between the in situ and MERIS data were obtained through strict exclusion criteria. Statistical analysis of R_(rs)(λ) showed a mean percentage difference(MPD) of 9%–13% in the 490–560 nm spectral range, and significant overestimation was observed at 413 nm(MPD>72%). The AOTs were overestimated(MPD>32%), and although the ESA algorithm outperformed the NASA algorithm in the blue-green bands, the situation was reversed in the red-near-infrared bands. The value of α was obviously underestimated by the ESA algorithm(MPD=41%) but not by the NASA algorithm(MPD=35%). To clarify why the NASA algorithm performed better in the retrieval of α, scatter plots of the α single scattering albedo(SSA) density were prepared. These α-SSA density scatter plots showed that the applicability of the aerosol models used by the NASA algorithm over the ECS is better than that used by the ESA algorithm, although neither aerosol model is suitable for the ECS region. The results of this study provide a reference to both data users and data agencies regarding the use of operational data products and the investigation into the improvement of current AC schemes over the ECS.

关键词： validation remote sensing reflectance aerosol optical thickness ocean color atmospheric correction remote sensing

heterologous expression of Hp BHY and Cr BKT increases heat tolerance in Physcomitrella patens

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Plant Diversity 2019年第4期41卷 266-274页

作者： Jianfang he Ping Li heqiang Huo Lina Liu Ting Tang mingxia he Junchao Huang Li Liu Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesYunnan Key Laboratory for Wild Plant ResourcesKunming650201China University of Chinese Academy of Sciences Beijing100049China Mid-Florida Research and Education Center Department of Environmental HorticultureUniversity of FloridaFL32703USA

heat stress can restrict plant growth,development,and crop *** essential plant antioxidants,carotenoids play significant roles in plant stress resistance.b-carotene hydroxylase(BHY)and b-carotene ketolase(BKT),which catalyze the conversions of b-carotene to zeaxanthin and b-carotene to canthaxanthin,respectively,are key enzymes in the carotenoid biosynthetic pathway,but little is known about their potential functions in stress ***,we investigated the roles of b-carotene hydroxylase and b-carotene ketolase during heat stress in Physcomitrella patens through expressing a b-carotene ketolase gene from Chlamydomonas reinhardtii(Cr BKT)and a b-carotene hydroxylase gene from Haematococcus pluvialis(Hp BHY)in the moss *** transgenic moss expressing these genes,carotenoids content increased(especially lutein content),and heat stress tolerance increased,with reduced leafy tissue *** investigate the mechanism of this heat stress resistance,we measured various physiological indicators and found a lower malondialdehyde level,higher peroxidase and superoxide dismutase activities,and higher endogenous abscisic acid and salicylate content in the transgenic plants in response to high-temperature *** results demonstrate that Cr BKT and Hp BHY increase plant heat stress resistance through the antioxidant and damage repair metabolism,which is related to abscisic acid and salicylate signaling.

关键词： Carotenoids heat stress Antioxidant Abscisic acid Physcomitrella patens

Terahertz spectral properties of melamine and its deuterated isotope,melamine-d_6

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Nuclear Science and Techniques 2012年第4期23卷 209-214页

作者： he mingxia LI Meng TIAN Zhen CAO Wei HAN Jiaguang Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin UniversityTianjin 300072China School of Electrical and Computer Engineering Oklahoma State UniversityStillwaterOklahoma 74078USA

The far-infrared optical properties of melamine and its deuterated isotope,melamine-d_6 were experimentally and theoretically investigated in the frequency range from 0.2 to 3.0 *** the room temperature and dry air nitrogen conditions,three absorption bands were observed at 2.0,2.3 and 2.6 THz in the melamine sample by use of terahertz time-domain ***,in the melamine-d_6 sample,the observed absorption bands shift towards lower frequencies and the relative intensity of the absorption bands *** simulation results based on the Parameterized Model number 3(PM3) were compared with the experimental data and the observed vibration spectra were assigned according to the PM3 *** absorption bands of the measured melamine samples at terahertz frequencies are highly correlated with the intermolecular hydrogen bond stretching and π-π stacking ***,the red shift of the absorption bands is due to hydrogen/deuterium substitution.

关键词：太赫兹时域光谱三聚氰胺氘同位素光谱特性分子间氢键频率范围实验数据吸收带

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外语教育:赋能“让世界读懂中国”的路径

外语电化教学 2022年第6期 59-64页

作者：何明霞湖北经济学院外国语学院湖北省武汉市430205

外语教育承载着传承弘扬中华文化,“让世界读懂中国”,引导国际舆论,塑造国家形象,推动中华文化创造性转化、创新性发展的重任。强化外语教育的政治性、工具性、人文性、实践性、系统性,将“让世界读懂中国”摆在外语教育的重要位置,讲... 详细信息

外语教育承载着传承弘扬中华文化,“让世界读懂中国”,引导国际舆论,塑造国家形象,推动中华文化创造性转化、创新性发展的重任。强化外语教育的政治性、工具性、人文性、实践性、系统性,将“让世界读懂中国”摆在外语教育的重要位置,讲好中国故事,传播中国声音,全面落实党的教育方针,构建外语教育三大体系,破解外语教育三大难题,提升国际话语权,提高外语教育效率,推动外语教育治理现代化,是外语教育赋能“让世界读懂中国”的有益尝试,对提升国家外语能力和文化软实力具有重要意义。

关键词：外语教育读懂中国课程思政讲好中国故事

基于蛋白质结构知识解析活性多肽的酶解制备反应行为(Ⅰ)酶解反应动态特性的3-D图形表征

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化工学报 2005年第12期56卷 2387-2391页

作者：齐崴何志敏何明霞天津大学化工学院化学工程研究所天津300072

提出了一种基于生物信息学知识与凝胶排阻色谱技术及图形拟合处理相结合的生物大分子复杂酶解反应行为定量分析、直观表征及模拟解析的新方法.研究中以全酪蛋白胰蛋白酶为模式水解体系,根据完整的HPSEC实验谱图,经分子模拟多肽结构,获... 详细信息

提出了一种基于生物信息学知识与凝胶排阻色谱技术及图形拟合处理相结合的生物大分子复杂酶解反应行为定量分析、直观表征及模拟解析的新方法.研究中以全酪蛋白胰蛋白酶为模式水解体系,根据完整的HPSEC实验谱图,经分子模拟多肽结构,获得了大量产物多肽信息;绘制了表征酶解反应动态特性的3D曲面图与21/2维伪彩色图,并对拟合曲面方程进行了数学分析,为调控酶解反应、定向和定量地高效获取目标活性多肽提供了理论依据.

关键词：酶解 3-D图形曲面拟合动态表征活性多肽蛋白质结构高效凝胶排阻色谱

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太赫兹光谱技术应用于聚烯烃薄膜孔隙率检测

激光与光电子学进展 2023年第9期60卷 446-452页

作者：栗擎何明霞天津大学精密仪器与光电子工程学院精密测试技术及仪器国家重点实验室天津300072 天津大学太赫兹研究中心天津300072

聚烯烃薄膜材料的孔隙率会影响材料的力学性能、绝缘性和贯通性,但少有对聚烯烃孔隙率无损检测的精确方法。本文以有效介电常数为桥梁,建立了四种材料等效折射率与孔隙率之间的等效模型;通过实际测试电池隔膜及微孔滤膜的太赫兹时域光谱... 详细信息

聚烯烃薄膜材料的孔隙率会影响材料的力学性能、绝缘性和贯通性,但少有对聚烯烃孔隙率无损检测的精确方法。本文以有效介电常数为桥梁,建立了四种材料等效折射率与孔隙率之间的等效模型;通过实际测试电池隔膜及微孔滤膜的太赫兹时域光谱,定量得到材料的折射率、介电常数、孔隙率等数据。结果表明:对于聚烯烃材料与空气的两相介质,其孔隙率与介电常数存在高相关性;采用改进的有效介质模型测得的孔隙率与常规的气体置换法测得的孔隙率的平均相对误差在2.53%左右;利用太赫兹光谱测量聚烯烃薄膜的孔隙率具备一定的可行性,有望成为薄膜检测的补充手段。

关键词：光谱学太赫兹时域光谱薄膜孔隙率有效介质理论聚烯烃材料

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自由基引发的凝胶化反应的Monte Carlo模拟

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高分子学报 2000年第1期10卷 61-64页

作者：徐建宽何明霞何志敏天津大学化学工程研究所天津300072

基于自由基凝胶化反应的基本原理，在一个具有周期性边界条件的二维网络上，利用动态ＭｏｎｔｅＣａｒｌｏ方法模拟了聚合物凝胶的自由基凝胶化反应，得到了凝胶的具体结构，研究了总单体浓度（单体浓度和交联剂浓度之和）对凝胶的... 详细信息

基于自由基凝胶化反应的基本原理，在一个具有周期性边界条件的二维网络上，利用动态ＭｏｎｔｅＣａｒｌｏ方法模拟了聚合物凝胶的自由基凝胶化反应，得到了凝胶的具体结构，研究了总单体浓度（单体浓度和交联剂浓度之和）对凝胶的分形结构和孔径分布的影响．模拟中首次考虑了聚合后单体的运动对凝胶结构的影响．结果表明：考虑聚合后单体的运动，可使所得凝胶网络的分形维数和凝胶化所需的最低浓度均显著小于动力学凝胶化模型和ＤＬＡ模型的相应值．用移动气泡法得到了凝胶网络的孔径分布，发现凝胶网络中大孔所占百分率明显多于随机纤维网络模型．

关键词：凝胶化反应蒙特卡罗模拟聚合物凝胶

Brief Introduction to a Unique Edible Bolete---Phlebopus portentosus in Southern China

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Journal of Agricultural Science and Technology(B) 2017年第6期7卷 386-394页

作者： Chunxia Zhang mingxia he Jing Liu Xinjing Xu Yang Cao Feng Gao Yiwei Fang Wenbing Wang Yun Wang Yunnan Institute for Tropical Crop Research 99 Xuanwei Rd. Jinghong 666100 Yunnan China The New Zealand Institute for Plant & Food Research Ltd. Private Bag 4704 Christchurch 8140 New Zealand

Abstraet： Phlebopus portentosus （Berk. and Broome） Boedijn is a favored wild edible mushroom in the Xishuangbanna region, Yunnan, China and Northern Thailand. It belongs to Boletinellaceae family and is known as ＂black bolete＂. Its ecological habits and biotrophy are very complicated. It can be saprobic and successfully cultivated in mushroom house conditions. More often it grows closely with many plants, but is not mycorrhizal fungus. It forms a tripartite association with root mealy bugs and plants. The fungus produces special fungus-insect gall with the soil mealy bugs, which is a symbiotic association between these two creatures. The gall grows on plant roots with parasitic tendency. This paper is a compact report of the findings, including taxonomy, ecology, economic and cultivation of this mushroom.

关键词： Phlebopusportentosus ecology cultivation fungus-insect gall biotrophy economy China.