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水体COD的光谱学在线测量方法-紫外和近红外光谱比较分析

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光谱学与光谱分析 2017年第9期37卷 2724-2729页

作者：刘飞董大明赵贤德郑培超北京农业智能装备技术研究中心北京市农林科学院北京100097 重庆邮电大学重庆400065

水体COD的光谱学传感技术是现代环境监测的一个重要发展方向,与传统的分析方法相比,光谱分析技术更具有可连续监测、可在线监测和检测快速的明显优势,适合对环境水样COD的定点实时监测。分别获取水样的紫外吸收光谱和近红外光谱,通过不... 详细信息

水体COD的光谱学传感技术是现代环境监测的一个重要发展方向,与传统的分析方法相比,光谱分析技术更具有可连续监测、可在线监测和检测快速的明显优势,适合对环境水样COD的定点实时监测。分别获取水样的紫外吸收光谱和近红外光谱,通过不同的光谱预处理方法结合偏最小二乘法、多元线性回归法建立水样的COD定量预测模型,对水体COD的紫外和近红外光谱的定量预测及相关模型参数进行分析,发现用S-G平滑处理后的紫外光谱和近红外光谱建立的PLS模型均得到最佳预测效果,预测集R^2.别为0.992.1和0.987 7,RMSEP分别为10.438 6和5.972.0。紫外和近红外光谱法的MLR模型预测效果较差,预测集R^2.别为0.92. 0和0.957 3。通过实验结果综合对比分析,紫外吸收光谱在2.0~310nm谱区建模预测性能较好,近红外光谱在7 2.0~6 870cm^(-1)谱区建模预测性能较好,紫外光谱对应定量预测模型的决定系数较高,而近红外光谱的稳定性和重复性更好。研究表明光谱传感技术可用于环境实际水体COD的定量预测分析,为开发便携式水体检测设备奠定了理论基础。

关键词： COD 紫外吸收光谱近红外透射光谱预测模型

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常用龈下刮治器械对磨牙根面刮治效率的比较

上海口腔医学 2017年第1期26卷 54-58页

作者：陈美华尹元正上海市口腔病防治院牙周病科上海200001 上海市交通大学医学院附属第九人民医院.口腔医学院牙周病科上海200011

目的 :比较压电式、磁伸缩式超声龈下刮治器及龈下手工器械3种临床常用龈下刮治器对磨牙根面的刮治效率,研究牙周袋深度及超声功率设定大小对超声器械龈下刮治效率的影响。方法:分别以压电式、磁伸缩式超声龈下刮治器械和龈下刮治手工... 详细信息

目的 :比较压电式、磁伸缩式超声龈下刮治器及龈下手工器械3种临床常用龈下刮治器对磨牙根面的刮治效率,研究牙周袋深度及超声功率设定大小对超声器械龈下刮治效率的影响。方法:分别以压电式、磁伸缩式超声龈下刮治器械和龈下刮治手工器械在2.min内对30例实验根面进行5或7 mm袋深、全功率或半功率设置的模拟龈下刮治,比较不同器械间的根面刮治效率。采用SAS6.12.件包对数据进行统计学分析。结果:不同参数设定下超声器械的刮治残留率均小于手工器械,全功率、5 mm袋深下磁伸缩式刮治残留率显著小于压电式(P2.7);而7 mm袋深时压电式、磁伸缩式与手工器械3者均无显著差异(P=0.574);7 mm袋深时的刮治残留率均显著高于5 mm袋深时(P<0.01);功率设定不同对于压电式或磁伸缩式超声器械的刮治影响均不显著。结论:超声龈下器械的刮治效率优于手工器械,3种器械的刮治效率均随牙周袋深度增加而下降。压电式与磁伸缩式器械无显著差异。超声龈下刮治器械的半功率设置对刮治效率的影响并不显著。

关键词：龈下刮治超声器械刮治效率

基于POD模型降阶法的非线性瞬态热传导分析

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中国科学：物理学、力学、天文学 2018年第12期48卷 32-41页

作者：梁钰郑保敬高效伟吴泽艳王峰大连理工大学航空航天学院大连116024 三峡大学水利与环境学院宜昌443002 大连理工大学工业装备结构分析国家重点实验室大连116024 三峡大学湖北省水电工程施工与管理重点实验室宜昌443002

本文结合特征正交分解(Proper Orthogonal Decomposition, POD)模型降阶法和有限元法,提出一种求解物性参数随温度变化的非线性瞬态热传导问题的快速算法.该方法利用简单线性问题的POD基底,快速计算复杂非线性问题,具有很高的工程应用价... 详细信息

本文结合特征正交分解(Proper Orthogonal Decomposition, POD)模型降阶法和有限元法,提出一种求解物性参数随温度变化的非线性瞬态热传导问题的快速算法.该方法利用简单线性问题的POD基底,快速计算复杂非线性问题,具有很高的工程应用价值.首先,对结构的线性瞬态热传导问题进行分析,在实验数据或数值方法计算结果的基础上,选取一些时刻结构的温度场构成瞬像矩阵,并对瞬像矩阵进行特征正交分解获得一组最优POD基底;其次,利用线性问题的POD基底对非线性瞬态热传导问题的有限元离散格式进行降阶分析,得到非线性瞬态热传导问题降阶模型的低阶常微分方程组;最后,通过求解降阶模型的常微分方程组获得结构各个时刻温度场的分布情况.文中通过几个数值算例验证了本文方法的有效性,计算结果表明本文方法具有良好的计算精度,并且计算效率能提高1–2.数量级.

关键词：特征正交分解模型降阶非线性瞬态热传导 POD基底瞬像矩阵

柑、橘、橙果皮中天然羟基化多甲氧基黄酮的转化率研究

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中国食品学报 2018年第5期18卷 294-301页

作者：韩丹丹毕金峰周沫徐明月谢宏郑金铠沈阳农业大学食品学院沈阳110161 中国农业科学院农产品加工研究所农业部农产品加工重点实验室北京100193

柑橘果皮中的多甲氧基黄酮,尤其是羟基化多甲氧基黄酮具有抗癌、抗炎等一系列显著的生物活性。本文建立一种有效分析柑橘种属羟基化多甲氧基黄酮的方法,对柑(芦柑)、橘(柳叶橘)、橙(赣南脐橙)果皮采用乙酸乙酯回流提取2.,继而分别用正... 详细信息

柑橘果皮中的多甲氧基黄酮,尤其是羟基化多甲氧基黄酮具有抗癌、抗炎等一系列显著的生物活性。本文建立一种有效分析柑橘种属羟基化多甲氧基黄酮的方法,对柑(芦柑)、橘(柳叶橘)、橙(赣南脐橙)果皮采用乙酸乙酯回流提取2.,继而分别用正己烷-甲醇(体积比1∶1)分别萃取,减压浓缩成浸膏,进行梯度洗脱的HPLC-UV分析。结果表明,柑橘种属果皮中多甲氧基黄酮主要集中于甲醇层,约占柑皮鲜重0.54%,橘皮、橙皮中含量略低。柑橘种属果皮中羟基化多甲氧基黄酮主要发生在黄酮母核A环5位上。柑皮中羟基化多甲氧基黄酮主要为5-羟基川陈皮素(141.39±1.84)μg/g、5-羟基橘皮素(19.67±1.2.)μg/g、5-羟基甜橙黄酮(13.98±2.2.)μg/g、5-羟基-3,6,7,8,3′,4′-六甲氧基黄酮(4.95±1.08)μg/g,转化率分别达到15.2.%,3.87%,39.12.和17.15%,转化水平显著高于橘皮和橙皮。橘皮中未检出5-羟基甜橙黄酮,橙皮中未检出5-羟基橘皮素。研究(羟基化)多甲氧基黄酮提取、检测及天然羟基化转化率,对深入挖掘柑橘原料资源,开发预防慢性疾病产品具有重要指导意义。

关键词：柑橘果皮多甲氧基黄酮羟基化多甲氧基黄酮高效液相色谱

基于逆转录酶结构和耐药突变的新型非核苷类逆转录酶抑制剂研究进展

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国际药学研究杂志 2018年第2期45卷 81-87页

作者：唐成润杨柳萌郑永唐昆明医科大学药学院暨云南省天然药物药理重点实验室昆明650500 中国科学院昆明动物研究所中国科学院和云南省动物模型与人类疾病机理重点实验室昆明650223

为了应对艾滋病治疗过程中严重的耐药性问题,开发新型抗耐药性非核苷类逆转录酶抑制剂(NNRTI)势在必行。本文通过分析2.15~2.18年文献报道的新型抗耐药性NNRTI的代表性实例,探讨了抗耐药性NNRTI与逆转录酶的结合模式,并讨论了药物化学... 详细信息

为了应对艾滋病治疗过程中严重的耐药性问题,开发新型抗耐药性非核苷类逆转录酶抑制剂(NNRTI)势在必行。本文通过分析2.15~2.18年文献报道的新型抗耐药性NNRTI的代表性实例,探讨了抗耐药性NNRTI与逆转录酶的结合模式,并讨论了药物化学策略在发现和优化新型抗HIV-1药物中的作用。本文指出基于逆转录酶晶体结构信息的药物化学策略是快速发现具有新结构的NNRTI的有效途径,前期构效关系研究能为后续的药物开发提供一定的支持。

关键词：艾滋病毒逆转录酶非核苷类逆转录酶抑制剂耐药性分子对接

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阿兹夫定体外抗登革病毒活性研究

药学学报 2018年第6期53卷 944-949页

作者：张春涛罗荣华陈欢刘光明常俊标杨柳萌郑永唐大理大学药学与化学学院云南大理671000 中国科学院昆明动物研究所云南省活性多肽研究与利用重点实验室/中国科学院动物模型与人类疾病重点实验室云南昆明650223 河南师范大学河南新乡453007

本文通过检测化合物对登革Ⅱ型重组病毒(DENV-ⅡLuc+)表达海肾荧光素酶活性的影响,进行化合物筛选,发现阿兹夫定(azvudine,FNC)、盐酸阿兹夫定(hydrochloride salt of azvudine,FNC-HCl)和三磷酸酯阿兹夫定(triphosphate azvudine,FNC-TP)能够抑制DENV-ⅡLuc+的复制,并研究其体外抗登革病毒(dengue virus,DENV)活性。首先通过噬斑法检测FNC、FNC-HCl和FNC-TP对DENV的抑制活性;并通过蛋白印迹实验检测3种化合物对DENV-Ⅱ囊膜蛋白E(envelope protein E)表达的影响,最后通过实时定量PCR检测化合物对DENV-Ⅱ病毒RNA的抑制作用。结果显示,FNC、FNC-HCl和FNC-TP抑制DENV复制的半数有效浓度(EC50)在0.54~2..42.mol·L^(-1)之间,阳性药物利巴韦林抑制DENV-Ⅱ的EC50为40.78±1.02.mol·L^(-1)。蛋白印迹实验及定量结果显示,3种化合物均能抑制DENV-Ⅱ囊膜蛋白E的表达,并且显著地抑制DENV-Ⅱ病毒RNA的复制。通过MTT法检测发现FNC、FNC-HCl和FNC-TP的细胞毒性很小,半数细胞毒性浓度(CC50)均大于3 000.00μmol·L^(-1)。本研究表明FNC、FNC-HCl和FNC-TP在细胞水平、蛋白水平及RNA水平均能抑制DENV的复制,且抑制作用优于利巴韦林,有望成为抗登革病毒的候选药物。

关键词：阿兹夫定登革病毒抗病毒活性体外

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： YongFei zheng School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 2.th century to a holistic kinematic-dynamic model in the 2.st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin

Discovery of the Significant Impacts of Swell Propagation on Global Wave Climate Change

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Journal of Ocean University of China 2024年第3期23卷 594-604页

作者： zheng Chongwei Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China

This study compared the differences in the wave climate in the South China Sea and North Indian Ocean under these two datasets:ERA-40 wave reanalysis and Mei’s hindcast wave *** the numerical calculation of regional ocean waves,the wave climate characteristics exhibited significant bias if the influence of external swells(swells from afar)was not fully considered,which may provide an incorrect basis for global climate change analysis.1)The trends of the significant wave height(SWH)obtained from the two datasets showed significant differences,such as those of the Bay of Bengal and the Java Sea in *** the past 45 years,SWH from ERA-40(SWH-ERA)exhibited a significant annual increase in low-latitude waters of the North Indian Ocean(0.2.0.6 cm yr^(-1))and South China Sea(0.2.0.8 cm yr^(-1)).2.In the Bay of Bengal,the SWH-ERA in each month was generally 0.5 m higher than the SWH from Mei’s hindcast wave data(SWH-Mei)and can reach 1.0 m higher in some months.3)In the Bay of Bengal,SWH-ERA and SWH-Mei increased significantly at annual rates of 0.13 and 0.2. cm yr^(-1),*** increasing trend was mainly reflected after ***-ERA showed a trough in 1975(1.33 m)and a crest in 1992.1.83 m),which were not reflected in SWH-Mei.

关键词： wave climate climatic trend monthly variation annual variation external swell

A positive trend in the stability of global offshore wind energy

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Acta Oceanologica Sinica 2024年第1期43卷 123-134页

作者： Chongwei zheng Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China

The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy *** the 40-year(1979–2.18)ERA-Interim data from the European Center for Medium-Range Weather Forecasts,this study presented the spatial-temporal distribution and climatic trend of the stability of global offshore wind energy as well as the abrupt phenomenon of wind energy stability in key regions over the past 40 years with the climatic analysis method and Mann-Kendall(M-K)*** results show the following 5 points.(1)According to the coefficient of variation(C_(v))of the wind power density,there are six permanent stable zones of global offshore wind energy:the southeast and northeast trade wind zones in the Indian,Pacific and Atlantic oceans,the Southern Hemisphere westerly,and a semi-permanent stable zone(North Indian Ocean).(2.There are six lowvalue zones for both seasonal variability index(S_(v))and monthly variability index(M_(v))globally,with a similar spatial distribution as that of the six permanent stable zones.M_(v) and S_(v) in the Arabian Sea are the highest in the world.(3)After C_(v),M_(v) and S_(v) are comprehensively considered,the six permanent stable zones have an obvious advantage in the stability of wind energy over other sea areas,with C_(v) below 0.8,M_(v) within 1.0,and S_(v) within 0.7 all the year round.(4)The global stability of offshore wind energy shows a positive climatic trend for the past four decades.C_(v),M_(v) and S_(v) have not changed significantly or decreased in most of the global ocean during 1979 *** is,wind energy is flat or more stable,while the monthly and seasonal variabilities tend to shrink/smooth,which is beneficial for wind energy utilization.(5)C_(v) in the low-latitude Pacific and M_(v) and S_(v) in both the North Indian Ocean and the low-latitude Pacific have an obvious abrupt phenomenon at the end of

关键词： global oceans wind energy stability spatial-temporal distribution climatic trend