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Rapid Determination of Amino Acids in Ginseng by High Performance Liquid Chromatography and Chemometric Resolution

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Chemical Research in Chinese Universities 2014年第4期30卷 578-581页

作者： HAN Jing wu Xi CAI wensheng SHAO Xueguang Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) State Key Laboratory of Medicinal Chemical Biology Research Center for Analytical Sciences College of Chemistry Nankai University Tianjin 300071 P. R. China

Ginseng is one of the most important traditional Chinese medicines and functional foods.A method for the fast determination of amino acids in ginseng samples using high performance liquid chromatography（HPLC） was developed,in which strong isocratic elution was employed for simplifying the separation and speeding up the *** amino acids were eluted within 3 min with the chromatogram composed of overlapped peaks from the ***,non-negative immune algorithm（NNIA） was adopted to resolve the chromatographic signals of the components from the chromatogram *** results show that the signals of the amino acids can be correctly extracted by NNIA and the signal extracted can be used for the quantitative *** method was validated via determining six amino acids of four different samples of *** recoveries of the spiked samples are in a range of 96.6％-106.3％.

关键词： High performance liquid chromatography(HPLC) Chemometrics Amino acid Ginseng Immune algorithm

A BLACK－SCHOLES FORMULA FOR OPTIONPRICINGWITHDIVIDENDS

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Applied Mathematics(A Journal of Chinese Universities) 1996年第2期11卷 159-164页

作者： XU wensheng\ AND\ wu ZHEN Department of Applied Mathematics Zhejiang University Hangzhou Department of Mathematics Shandong University Jinan

We obtain a Black Scholes formula for the arbitrage free pricing of European Call options with constant coefficients when the underlying stock generates dividends. To hedge the Call option, we will always borrow money form bank. We see the influence of the dividend term on the option pricing via the comparison theorem of BSDE(backward stochastic differential equation,). We also consider the option pricing problem in terms of the borrowing rate R which is not equal to the interest rate r. The corresponding Black Scholes formula is given. We notice that it is in fact the borrowing rate that plays the role in the pricing formula.

关键词： Black Scholes formula optionpricing stock market dividends.

Thin bed responses and correction methods for cased hole density logging

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Petroleum Science 2008年第4期5卷 322-325页

作者： wu wensheng Zhang Yuling State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China China National Logging Corporation CNPC Beijing 100101 China

The study of the thin bed responses and correction methods in cased hole density logging can provide a theoretical basis for research to improve data processing methods. By using the Monte Carlo program MCNP, the change of detector count from thin beds with the vertical depth was calculated at different casing thicknesses. The calculation showed that with the low density thin bed moving upward, detector count first increased to a maximum then decreased. The responses of a thin bed with a high density were opposite to those of a thin bed with a low density. The change curve was symmetrical, and the maximums or minimums appeared at the midpoint between the detector and source. Besides, detector count increased with increasing thin bed thickness. At a specific thin bed thickness, further increase of thin bed thickness resulted in a slow increase of detector count then the count rate leveled off. In actual logging, the influence of adjacent formations on density log measurements can be ignored. Finally, based on numerical simulation correction methods for the dual influence of casing and thin beds are discussed.

关键词： Density logging in cased hole thin bed response casing MCNP program correcting

A study on the temperature sensitivity of NMR porosity in porous media based on the intensity of magnetization Dedicated to the special issue “Magnetic Resonance in Porous Media”

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Magnetic Resonance Letters 2024年第1期4卷 28-39页

作者： Lu Zhang Lizhi Xiao wensheng wu Guangzhi Liao Yan Zhang Sihui Luo Xinglong Lei National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Geophysics China University of PetroleumBeijing102249China PetroChina Huabei Oilfield Company China National Petroleum CorporationRenqiu062552China

The measurement of nuclear magnetic resonance(NMR)porosity is affected by *** considering the impact of NMR logging tools,this phenomenon is mainly caused by variations in magnetization intensity of the measured system due to temperature fluctuations and difference between the temperature of the porous medium and calibration *** this study,the effect of temperature was explained based on the thermodynamic theory,and the rules of NMR porosity responses to temperature changes were identified through core physics *** addition,a method for correcting the influence of temperature on NMR porosity measurement was proposed,and the possible factors that may affect its application were also discussed.

关键词： NMR porosity Temperature Porous media Intensity of magnetization

Late Middle Pleistocene Harbin cranium represents a new Homo species

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The Innovation 2021年第3期2卷 3-4页

作者： Qiang Ji wensheng wu Yannan Ji Qiang Li Xijun Ni Hebei GEO University Shijiazhuang 050031China China Geo-Environmental Monitoring Institute Beijing 100081China CAS Center for Excellence in Life and Paleoenvironment Chinese Academy of ScienceBeijing 100044China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of ScienceBeijing 100104China

In eastern Asia,several Middle-Late Pleistocene human fossils,such as the Dali,Jinniushan,Hualongdong,and Harbin crania,evidently resemble each other and are phylogenetically closer to *** than to *** or other archaic humans.1 The Harbin cranium is the best preserved of this *** shows a mosaic combination of plesiomorphic and apomorphic ***,we suggest that the Harbin skull should be recognized as a new species of Homo.

关键词： Middle closer ani

基于SSA-XGBoost模型的高精度密度测井预测方法研究

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核技术 2024年第12期47卷 82-94页

作者：李瑞吴文圣中国石油大学(北京)地球物理学院北京102249

复杂岩性井段对密度测井数据精度要求很高,传统的计算模型难以满足此类高精度要求,为此提出利用机器学习密度预测模型提高密度测井曲线的精度。首先,使用蒙特卡罗模拟双探测器密度测井仪器,获取不同地层的密度测井数据用以训练和测试机... 详细信息

复杂岩性井段对密度测井数据精度要求很高,传统的计算模型难以满足此类高精度要求,为此提出利用机器学习密度预测模型提高密度测井曲线的精度。首先,使用蒙特卡罗模拟双探测器密度测井仪器,获取不同地层的密度测井数据用以训练和测试机器学习模型。考虑到密度预测模型的过拟合问题和不同模型的密度补偿性能,基于麻雀搜索算法(Sparrow SearchAlgorithm,SSA)分别改进XGBoost、支持向量回归(Support Vector Regression,SVR)、随机森林回归(Random Forest Regression,RFR)和长短记忆网络(Long Short-Term Memory,LSTM)等模型,进而提出了SSA-XGBoost、SSA-SVR、SSA-RFR和SSA-LSTM密度预测模型。然后,使用量化评价指标和泰勒图模型对比分析各个模型的预测性能,分析了不同预测模型对实际密度测井数据的预测效果。结果表明:SSA-XGBoost模型的预测精度高于传统脊-肋图模型和其他机器学习模型,其预测地层密度的误差为0.0174 g∙cm^(-3),远低于传统脊-肋图法的0.0284 g∙cm^(-3),因此在实际密度测井数据处理中具有广阔的应用前景。

关键词： SSA-XGBoost 蒙特卡罗模拟机器学习密度预测

Geochemical provenancing and direct dating of the Harbin archaic human cranium

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The Innovation 2021年第3期2卷 62-69页

作者： Qingfeng Shao Junyi Ge Qiang Ji Jinhua Li wensheng wu Yannan Ji Tao Zhan Chi Zhang Qiang Li Rainer Grun Chris Stringer Xijun Ni Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China CAS Center for Excellence in Life and Paleoenvironment Chinese Academy of ScienceBeijing 100044China University of Chinese Academy of Sciences Beijing 100049China Hebei GEO University Shijiazhuang 050031China Key Laboratory of Earth and Planetary Physics Innovation Academy for Earth ScienceChinese Academy of SciencesBeijing 100029China China Geo-Environmental Monitoring Institute Beijing 100081China The Second Hydrogeology and Engineering Geology Prospecting Institute of Heilongjiang Province Harbin 150030China Australian Research Centre for Human Evolution Griffith UniversityNathanQLDAustralia Research School of Earth Sciences The Australian National UniversityCanberraACTAustralia Centre for Human Evolution Research Department of Earth SciencesNatural History MuseumLondonUK CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of ScienceBeijing 100104China

As one of the most complete archaic human fossils,the Harbin cranium provides critical evidence for studying the diversification of the Homo genus and the origin of Homo ***,the unsystematic recovery of this cranium and a long and confused history since the discovery impede its accurate ***,we carried out a series of geochemical analyses,including non-destructive X-ray fluorescence(XRF),rare earth elements(REE),and the Sr isotopes,to test the reported provenance of the Harbin cranium and get better stratigraphic *** results show that the Harbin cranium has very similar XRF element distribution patterns,REE concentration patterns,and Sr isotopic compositions to those of the Middle Pleistocene-Holocene mammalian and human fossils recently recovered from the Harbin *** sediments adhered in the nasal cavity of the Harbin cranium have a 87Sr/86Sr ratio of 0.711898,falling in the variation range measured in a core drilled near the Dongjiang Bridge,where the cranium was discovered during its *** regional stratigraphic correlations indicate that the Harbin cranium was probably from the upper part of the Upper Huangshan Formation of the Harbin area,which has an optically stimulated luminescence dating constraint between 138 and 309 ka.U-series disequilibrium dating(n=10)directly on the cranium suggests that the cranium is older than 146 *** multiple lines of evidence from our experiments consistently support the theory that the Harbin cranium is from the late Middle Pleistocene of the Harbin *** study also shows that geochemical approaches can provide reliable evidence for locating and dating unsystematically recovered human fossils,and potentially can be applied to other human fossils without clear provenance and stratigraphy records.

关键词： human fossil provenancing non-destructive X-ray fluorescence rare earth elements strontium(Sr)isotopic composition uranium-series disequilibrium(U-series)dating

STUDY AND APPLICATION ABOUT COMPUTED SYSTEM FOR EXTERNAL CARDIAC MASSAGE, MONITOR OF HEART AND BODY TEMPERATURE

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现代电生理学杂志 2006年第1期13卷 26-27页

作者： LIU Mingshun wu wensheng MENG Fanhang ZHU Shouzeng The Fourth Affiliated Hospital of Hebei Medical University Shijiazhuang 050011 石家庄市第二职业中专学校 Hebei Eletron Technique Research Institute Shijazhuang 050000

Objective:To make and study computed system for external cardiac massage,monitor of heart and body temperature and observe its clinical ***:The system was made and ***:The effect of system was ***: The system was an e... 详细信息

关键词： computed system for external cardiac massage,monitor of heart and body temperature study clinical application

Massive cranium from Harbin in northeastern China establishes a new Middle Pleistocene human lineage

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The Innovation 2021年第3期2卷 43-50页

作者： Xijun Ni Qiang Ji wensheng wu Qingfeng Shao Yannan Ji Chi Zhang Lei Liang Junyi Ge Zhen Guo Jinhua Li Qiang Li Rainer Grun Chris Stringer Hebei GEO University Shijiazhuang 050031China CAS Center for Excellence in Life and Paleoenvironment Chinese Academy of ScienceBeijing 100044China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of ScienceBeijing 100104China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China China Geo-Environmental Monitoring Institute Beijing 100081China Key Laboratory of Earth and Planetary Physics Innovation Academy for Earth ScienceChinese Academy of SciencesBeijing 100029China Australian Research Centre for Human Evolution Griffith UniversityNathanQLDAustralia Research School of Earth Sciences The Australian National UniversityCanberraACTAustralia Centre for Human Evolution Research Department of Earth SciencesNatural History MuseumLondonUK

It has recently become clear that several human lineages coexisted with Homo sapiens during the late Middle and Late ***,we report an archaic human fossil that throws new light on debates concerning the diversification of the Homo genus and the origin of *** fossil was recovered in Harbin city in northeastern China,with a minimum uranium-series age of 146 *** cranium is one of the best preserved Middle Pleistocene human *** massive size,with a large cranial capacity(1,420 mL)falling in the range of modern humans,is combined with a mosaic of primitive and derived *** differs from all the other named Homo species by presenting a combination of features,such as long and low cranial vault,a wide and low face,large and almost square orbits,gently curved but massively developed supraorbital torus,flat and low cheekbones with a shallow canine fossa,and a shallow palate with thick alveolar bone supporting very large *** excellent preservation of the Harbin cranium advances our understanding of several less-complete late Middle Pleistocene fossils from China,which have been interpreted as local evolutionary intermediates between the earlier species Homo erectus and later *** analyses based on parsimony criteria and Bayesian tip-dating suggest that the Harbin cranium and some other Middle Pleistocene human fossils from China,such as those from Dali and Xiahe,form a third East Asian lineage,which is a part of the sister group of the *** *** analyses of such morphologically distinctive archaic human lineages from Asia,Europe,and Africa suggest that the diversification of the Homo genus may have had a much deeper timescale than previously *** isolation of small populations combined with stochastic long-distance dispersals is the best fitting biogeographical model for interpreting the evolution of the Homo genus.

关键词： human phylogeny human cranium fossil human dispersal human diversification