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The temporal and spatial relationship between NDVI and climatological parameters in Colorado

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Journal of Geographical Sciences 2001年第4期11卷 31-39页

作者： Gao Zhi-qiang O. dennis Institute of Geographic Sciences and Natural Resources Research CAS Natural Resource Ecology Laboratory Colorado State University Fort Collins.

This paper describes the spatial and temporal relationship between AVHRR/NDVI (Normalized Difference Vegetation Index) and climatological parameters (temperature and precipitation), which, in some sense, is influenced by topographical factors and land-cover types in Colorado. The correlation coefficients and partial correlation coefficients have been computed pixel by pixel over Colorado in order to analyze the relationship. The temporal variation and correlation of AVHRR/NDVI, temperature and precipitation were analyzed with a sampling method. The study reveals that there exists a close correspondence between monthly NDVI and temperature, which has strong impact from temperature on the changes of NDVI in Colorado. The spatial changes of NDVI are not influenced obviously by the precipitation since these two variables are different from each other in time series in Colorado. The study clearly revealed the spatial variation and its distribution patterns of relationship between NDVI and climatic parameters (temperature and precipitation) in Colorado.

关键词： NDVI AVHRR/NDVI temperature precipitation Colorado

Enhancing heat transfer at the micro-scale using elastic turbulence

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Theoretical & Applied Mechanics Letters 2015年第3期5卷 103-106页

作者： R.D.whalley w.M.Abed D.J.C.dennis R.J.Poole School of Engineering University of Liverpool LMFA Universite de LyonEcole Centrale de Lyon

Small concentrations of a high-molecular-weight polymer have been used to create so-called ＂elastic tur- bulence＂ in a micro-scale serpentine channel geometry. It is known that the interaction of large elastic stresses created by the shearing motion within the fluid flow with streamline curvature of the serpentine geometry leads initially to a purely-elastic instability and then the generation of elastic turbulence. we show that this elastic turbulence enhances the heat transfer at the micro-scale in this geometry by up to 300% under creeping flow conditions in comparison to that achieved by the equivalent Newtonian fluid flow.

关键词： Elastic turbulence Viscoelasticity Serpentine channel Micro-mixing Heat transfer

Visible-Light-Induced Radical Cascade Cyclization： Synthesis of（20S）-Camptothecin, SN-38 and Irinotecan

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Chinese Journal of Chemistry 2018年第11期36卷 1035-1040页

作者： Yao Yuan wuheng Dong Xiaoshuang Gao Xiaomin Xie dennis P. Curran Zhaoguo Zhang Shanghai Key Laboratory for Molecular Engineering Of Chiral Drugs School of Chemistry and Chemical Engineering Shanghai Jiao Tong Uni- versity 800 Dongchuan Road Shanghai 200240 China Department of Chemistry University of Pittsburgh Pittsburgh Pennsyl-vania PA 15260 USA

(20 S )‐Camptothecin, irinotecan and SN‐38 were successfully synthesized by a photocatalyzed radical cascade cyclization from an N ‐propargyl iodopyridinone and an arylisonitrile under visible light with a ruthenium catalyst. This synthetic method provided a useful entry into composing camptothecin family of antitumor agents in good yields under mild reaction conditions without the use of heavy metal reagents.

关键词： photocatalysis radicals camptothecin irinotecan SN‐38 ruthenium

Carrier-free nanodrugs with efficient drug delivery and release for cancer therapy:From intrinsic physicochemical properties to external modification

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Bioactive Materials 2022年第2期7卷 220-240页

作者： Heng Mei Shengsheng Cai dennis Huang Huile Gao Jun Cao Bin He National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China west China School of Pharmacy Sichuan UniversityChengdu610064China Department of Biomedical Engineering The University of Texas at AustinAustinTX78731USA

The considerable development of carrier-free nanodrugs has been achieved due to their high drug-loading capability,simple preparation method,and offering“all-in-one”functional platform ***,the native defects of carrier-free nanodrugs limit their delivery and release behavior throughout the in vivo journey,which significantly compromise the therapeutic efficacy and hinder their further development in cancer *** this review,we summarized and discussed the recent strategies to enhance drug delivery and release of carrier-free nanodrugs for improved cancer therapy,including optimizing the intrinsic physicochemical properties and external ***,the corresponding challenges that carrier-free nanodrugs faced are discussed and the future perspectives for its application are *** hope this review will provide constructive information for the rational design of more effective carrier-free nanodrugs to advance therapeutic treatment.

关键词： Carrier-free nanodrugs Drug delivery and release Intrinsic physicochemical properties External modification Therapeutic efficacy

The development of *** erosion prediction and modeling

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International Soil and water Conservation Research 2013年第2期1卷 1-11页

作者： John M.Laflen dennis C.Flanagan lowa State U. USDA-ARS National Soil Erosion Research Laboratory West LafayetteIN

Soil erosion prediction technology began over 70 years ago when Austin Zingg published a relationship between soil erosion(by water)and land slope and length,followed shortly by a relationship by Dwight Smith that expanded this equation to include conservation ***,it was nearly 20 years before this work's expansion resulted in the Universal Soil Loss Equation(USLE),perhaps the foremost achievement in soil erosion prediction in the last *** USLE has increased in application and complexity,and its usefulness and limitations have led to the development of additional technologies and new science in soil erosion research and *** among these new technologies is the water Erosion Prediction Project(wEPP)model,which has helped to overcome many of the shortcomings of the USLE,and increased the scale over which erosion by water can be *** of application of erosion prediction include almost all land types:urban,rural,cropland,forests,rangeland,and construction *** applications of wEPP include prediction of radioactive material movement with soils at a superfund cleanup site,and near real-time daily estimation of soil erosion for the entire state of Iowa.

关键词： Universal Soil Loss Equation water Erosion Prediction Project Soil erosion Erosion prediction History of erosion prediction

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基于人工神经网络的注水开发油藏产量预测

石油勘探与开发 2020年第2期47卷 357-365页

作者： NEGASH Berihun Mamo YAw Atta dennis 马来西亚石油大学石油工程系马来西亚斯里依斯干达32610

针对传统注水开发油藏产量预测方法存在的问题,提出了基于人工神经网络的预测模型,阐述了模拟工作流程,并进行了算例分析。提出了基于流体物理学和测量数据随机组合的特征提取方法,以提高模型的预测效果。优选贝叶斯正则化算法作为模型... 详细信息

针对传统注水开发油藏产量预测方法存在的问题,提出了基于人工神经网络的预测模型,阐述了模拟工作流程,并进行了算例分析。提出了基于流体物理学和测量数据随机组合的特征提取方法,以提高模型的预测效果。优选贝叶斯正则化算法作为模型的训练算法,该算法一般耗时较长,但能对产油量、产气量、产水量等嘈杂数据集进行良好泛化。通过计算均方误差及决定系数、绘制误差分布直方图及模拟数据-验证数据交会图等方式进行模型评价。用90%的历史数据训练、验证、测试目标模型结构,然后用其余10%数据进行盲测。研究表明,提出的流体产量预测模型决定系数超过0.9,模拟结果与实际数据吻合程度高,输入信息少,计算成本低。

关键词：人工神经网络机器学习特征提取贝叶斯正则化算法产量预测注水开发

Effect of Selenium on Aflatoxin Hepatocarcinogenesis in the Rat

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Biomedical and Environmental Sciences 1990年第1期3卷 65-80页

作者： BORIS H.RUEBNER dennis P. H. HSIEH Department of Pathology Department of Environmental Toxicology University of California Davis California 95616

The effects of selenium (Na_2SeO_3) on aflatoxin B_1 (AFB_1)-induced hepatic neoplasia were studied in the rat. Putative preneoplastic foci and nodules composed of basophilic, eosinophilic, and clear cells developed early. Basophilic foci were seen first; in the later stages basophilic and eosinophilic nodules predominated. At each stage the AFB_1 + Se groups showed fewer and smaller foci and nodules than the AFB_1 -Se group. The number of foci in the AFB_1 + 3 ppm Se group and their mean area were smaller than those in the 6 ppm Se + AFB_1 group. At the end of the experiment hepatocellular carcinoma (HCC) was found in 11/18 rats (61%) of the AFB_1-Se group. HCC was not found in either of the groups given AFB_1 +Se. we conclude that Se had an inhibitory effect on the initiation and promotion stages of AFB_1-induced preneoplastic foci and nodules. Se also prevented progression of these nodules to HCC even after cessation of AFB_1 administration. The inhibitory effect of Se at 3 ppm was greater than at 6 ppm. The 6 ppm Se group also showed evidence of toxicity. 1990 Academic ***.

关键词： Effect of Selenium on Aflatoxin Hepatocarcinogenesis in the Rat

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In Memoriam:*** ***

International Soil and water Conservation Research 2021年第4期9卷 485-489页

作者： dennis C.Flanagan Richard M.Cruse James L.Baker Paige Chyu USDA-Agricultural Research Service National Soil Erosion Research LaboratoryWest LafayetteINUSA Department of Agronomy Iowa State UniversityAmesIAUSA Department of Agricultural&Biosystems Engineering Iowa State UniversityAmesIAUSA International Research and Training Center on Erosion and Sedimentation BeijingChina

The soil erosion research and soil and water conservation global community lost a treasured member on November 20,2020,when *** Matthew Laflen(Fig.1)*** one with a friendly welcoming smile,John had hundreds of friends,both personally and professionally throughout the *** article includes many of his professional and scientific contributions,and impacts from his research and outreach activities.

关键词： soil hundreds professional

DECAY PROCESSES OF HIGH-FREQUENCY NONEQUILIBRIUM PHONONS IN PRASEODYMIUM-DOPED LASER CRYSTALS

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发光学报 1999年第2期 40-48页

作者： wang Xiaojun a) dennis w M b) Yen w M b) a) (Department of Physics & Astronomy, Georgia Southern University, Statesboro, GA 30460, USA) b) (Department of Physics and Astronomy, The University of Georgia, Athens, GA 3

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎａｒｅａｌｃｒｙｓｔａｌｓｙｓｔｅｍ，ｔｈｅｌａｔｉｃｅｖｉｂｒａｔｉｏｎｓｗｉｌｎｏｔｂｅｔｈｅｅｉｇｅｎｓｔａｔｅｓｏｆｔｈｅｓｙｓ－ｔｅｍ，ｉ．ｅ．，ａｎｉｎｉｔｉａｌｙｍｏｎｏｃ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎａｒｅａｌｃｒｙｓｔａｌｓｙｓｔｅｍ，ｔｈｅｌａｔｉｃｅｖｉｂｒａｔｉｏｎｓｗｉｌｎｏｔｂｅｔｈｅｅｉｇｅｎｓｔａｔｅｓｏｆｔｈｅｓｙｓ－ｔｅｍ，ｉ．ｅ．，ａｎｉｎｉｔｉａｌｙｍｏｎｏｃｈｒｏｍａｔｉｃｎｏｎｅｑｕｉｌｉ...

关键词： nonequilibrium phonons high frequency phonons lattice dynamics YAG YLF