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Journal of Analysis and Testing 2018年第2期2卷 138-148页

作者： Xinyi Wang Peter de Boves Harrington clippinger laboratories Department of Chemistry and BiochemistryCenter for Intelligent Chemical InstrumentationOhio UniversityAthensOH 45701‑2979USA

As a global staple,rice has an increasing demand for differentiation and authentication,considering both fraud and health aspects for *** complexity of rice urges a rapid,labor-saving,effective,and economical rice differentiation method.A semi-quantitative method using inductively coupled plasma mass spectrometry(ICP–MS)for fast and highthroughput analysis of rice entire elements with singular value decomposition(SVD)background correction(BC)was *** SVD BC method is the first time that it has been used with ICP–MS to minimize the effect of instrumental *** data preprocessing methods,normalization(NM),error scaling(ES),and standard normal variate(SNV)were evaluated by principal component analysis(PCA)and projected difference resolution(PDR).A fuzzy rule-building expert system(FuRES),super partial least squares discriminant analysis(sPLS-DA),support vector machine(SVM),and SVM classification tree(SVMTreeG)classifiers gave 98.1±0.0,99.8±0.4,99.8±0.4,and 100.0±0.0%prediction rates with all of the data preprocessing methods(NM,SVD BC with one component to reconstruct the background,ES,and SNV)for the differentiation of the nine rice-digested samples,respectively.

关键词： Rice ICP–MS SVD PDR SVMTree FuRES

Chemometrics in the Age of Intelligent Chemical Instruments

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Journal of Analysis and Testing 2018年第3期2卷 191-192页

作者： Peter de Boves Harrington1 clippinger laboratories Department of Chemistry and BiochemistryCenter for Intelligent Chemical InstrumentationOhio UniversityAthensOH 45701-2979USA

We are presently living through a dawning of a new era for which artificial intelligence(AI)will affect every aspect of our daily ***,smartphones contain digital personal assistants that can translate our voice commands into digital signals that can control our phones or purchase items for us through the *** advances in our personal technology can also be used for analysis and testing.

关键词： translate smart artificial

Spectral Representation of Proton NMR Spectroscopy for the Pattern Recognition of Complex Materials

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Journal of Analysis and Testing 2017年第2期1卷 1-11页

作者： Peter de B.Harrington Xinyi Wang clippinger laboratories Department of Chemistry and BiochemistryCenter for Intelligent Chemical InstrumentationOhio UniversityAthensOH 45701-2979USA

Proton nuclear magnetic resonance(NMR)spectroscopy provides a powerful tool for chemical profiling,also known as spectral fingerprinting,because of its inherent *** is now increasing in use for authentication of complex ***,the absorbance spectrum is used that is obtained as the phase-corrected real component of the Fourier transform(FT)of the free induction decay(FID).However,the practice discards half the information that is available in the dispersion spectrum obtained as the imaginary component from the *** qualitative analysis or quantitative analysis of small sets of absorbance peaks,the symmetric and sharp peaks of the real spectra work ***,for pattern recognition of entire spectra,trading peak resolution for peak reproducibility is *** absolute value of the complex spectrum gives the length or magnitude of magnetization vector in the complex plane;therefore,the magnitude relates directly to the signal(i.e.,induced magnetization).The magnitude spectrum is obtained as the absolute value from the real and imaginary spectral components after the FT of the *** breaking with tradition and using the magnitude spectrum the reproducibility of the spectra and consequent recognition rates can be *** study used a 500-MHz 1H NMR instrument to obtain spectra from 4 diverse datasets;12 tea extracts,8 liquor samples,9 hops extracts,and 25 Cannabis *** classifiers were statistically evaluated using 100 bootstrapped Latin *** classifiers were a fuzzy rule-building expert system(FuRES)tree,support vector machine trees(SVMTreeG and SVMTreeH),a regularized linear discriminant analysis(LDA),super partial least squares discriminant analysis(sPLS-DA),and a one against all support vector machine(SVM).All classifiers gave better or equivalent results for the magnitude spectral representation than for the real spectra,except for one case of the 24 *** addition,the enhanced reproducibilit

关键词： Cannabis Tea Hops Liquor HumulusNMR fingerprinting Magnitude spectrum Absolute value spectrum Pattern recognition Classification

Application of Generalized Standard Addition Method and Ultraviolet Spectroscopy to Quantify Electrolytic Depolymerization of Lignin

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Journal of Analysis and Testing 2020年第1期4卷 35-44页

作者： Zewei Chen Mahtab NaderiNasrabadi John A.Staser Peter B.Harrington Department of Chemistry and Biochemistry Clippinger LaboratoriesOhio UniversityAthensOH 45701USA Department of Chemical and Biomolecular Engineering Center for Electrochemical Engineering ResearchOhio UniversityAthensOH 45701USA

Industrial lignin waste is an important byproduct of bio-refineries and the paper *** of industrial lignin could generate useful aromatic *** group has focused on electrolytic decomposition of biorefinery *** quantify electrolytic decomposition of the lignin in a highly caustic solution,ultraviolet(UV)spectroscopy provides a useful *** conversion of the neat lignin to the oxidized products achieved by the electrolytic reactor may be measured by quantifying the amount of unreacted neat lignin that remains in the *** the properties of electrolytic decomposition products are largely unknown,a useful approach to quantify decomposition of the neat lignin is to use a multivariate calibration method referred to as the generalized standard addition method(GSAM).In this approach,the electrolytic decomposition products represent a background interference and the neat lignin that remains can be *** approach allows the conversion of the neat lignin to be calculated in a solution that is a complex mixture.

关键词： GSAM Lignin depolymerization Electrolytic reactor UV spectroscopy Best linear unbiased estimator(BLUE)

High-Throughput Chemotyping of Cannabis and Hemp Extracts Using an Ultraviolet Microplate Reader and Multivariate Classifiers

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Journal of Analysis and Testing 2018年第3期2卷 210-222页

作者： Zewei Chen Peter de Boves Harrington Steven F.Baugh clippinger laboratories Department of Chemistry and BiochemistryCenter for Intelligent Chemical InstrumentationOhio UniversityAthensOH 45701USA Chemistry Mapping Inc.5902 McIntyre St.GoldenCO 80403USA

As the use of Cannabis products as natural medicines burgeons,it is also appearing as a food *** is important to screen Cannabis samples as ingredients by profiling their chemical compositions,which is referred to as *** sets of botanical extracts were *** first set is referred to as Cannabis contained plant materials from 15 samples of the sativa,indica,and hybrids of the two *** second set contained 20 extracts from the variety of Cannabis sativa with low tetrahydrocannabinol(THC)concentrations,i.e.,below 0.3%,and,henceforth,will be referred to as *** ultraviolet(UV)microplate reader provides a cost-effective and high-throughput method for identifying chemotypes of plant extracts by their *** microplate reader affords rapid measurements of small volumes,e.g.,50μL,which demonstrates a potential to significantly reduce the analysis time and cost for Cannabis and hemp chemotyping or chemi-cal *** samples were measured on different days to demonstrate the robustness of the *** difference resolution(PDR)maps were used to visualize the separations among the *** multivariate classifiers,fuzzy rule-building expert system(FuRES),super partial least squares-discriminant analysis(sPLS-DA),support vector machine(SVM),and two tree-based support vector machines(SVMtreeG and SVMtreeH)were *** classifiers were validated with ten bootstrapped Latin partitions(BLPs).For the Cannabis extracts,the SVMtreeG yielded the best performance and the classification accuracy was 99.1±0.4%for spectra collected in the nonlinear absorbance *** the hemp extracts,the SVM classifier performed the best with a 97.4±0.6%classification *** results demonstrate that the UV microplate reader coupled with multivariate classifiers can be used as a high-throughput and cost-effective approach for chemotyping Cannabis.

关键词： Cannabis extracts Hemp extracts Ultraviolet microplate reader Multivariate models High-throughput chemotyping Chemometrics Projected difference resolution map

Origins of the supercontinent cycle

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Geoscience Frontiers 2013年第4期4卷 439-448页

作者： R.Damian Nance J.Brendan Murphy Department of Geological Sciences.316 Clippinger Laboratories.Ohio University.Athens.OH 45701.USA Department of Earth Sciences st.Francis Xavier UniversityAntigonishNova Scotia B2G 2W5.Canada

The supercontinent cycle, by which Earth history is seen as having been punctuated by the episodic assembly and breakup of supercontinents, has influenced the rock record more than any other geologic phenomena, and its recognition is arguably the most important advance in Earth Science since plate tectonics. It documents fundamental aspects of the planet＇s interior dynamics and has charted the course of Earth＇s tectonic, climatic and biogeochemical evolution for billions of years. But while the widespread realization of the importance of supercontinents in Earth history is a relatively recent development, the supercontinent cycle was first proposed thirty years ago and episodicity in tectonic processes was recognized long before plate tectonics provided a potential explanation for its occurrence. With interest in the supercontinent cycle gaining momentum and the literature expanding rapidly, it is instructive to recall the historical context from which the concept developed. Here we examine the supercontinent cycle from this perspective by tracing its development from the early recognition of long-term epi- sodicity in tectonic processes, through the identification of tectonic cycles following the advent of plate tectonics, to the first realization that these phenomena were the manifestation of episodic superconti- nent assembly and breakup.

关键词： Supercontinent cyclePlate tectonicsTectonic episodicitySecular trends

离子淌度谱和SIMPLISMA用于痕量有机化合物的检测

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光谱学与光谱分析 2005年第9期25卷 1530-1533页

作者：张卓勇陈国祥 Harrington Peter de B 首都师范大学化学系 Department of Chemistry and Biochemistry Center for Intelligent Chemical Instrumentation Clippinger Laboratories Ohio University Athens Ohio 45701-2979 USA

离子淌度谱(IMS)是检测痕量挥发性有机化合物的灵敏方法。SIMPLISMA(simpletouseinteractiveselfmodelingmixtureanalysis)是一种自模型曲线分辨方法。文章将SIMPLISMA用于DMMP,DIMP和DEMP的IMS检测和数据的处理。这些化合物的IMS谱数据经SIMPLISMA处理后,可以提取出IMS的谱特征,并去除大部分噪声的影响。经SIMPLISMA提取的IMS谱可被用于其他计算,如曲线分辨和模式识别等。

关键词：离子淌度谱 SIMPLISMA 化学计量学数据处理甲基瞵酸酯

Switching from advancing to retreating subduction in the Neoproterozoic Tarim Craton, NW China: Implications for Rodinia breakup

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Geoscience Frontiers 2021年第1期12卷 161-171页

作者： Guanghui Wu Shuai Yang Wei Liu R.Damian Nance Xin Chen Zecheng Wang Yang Xiao School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China Southwest Petroleum University Division of Key Laboratory of Carbonate ReservoirsCNPCChengdu 610500China PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China Department of Geological Sciences 316 Clippinger LaboratoriesOhio UniversityAthensOH 45701USA

Geodynamic drivers for the supercontinent cycle are generally attributed to either top-down(subduction-related)or bottom-up(mantle-related)*** geochemical data and U-Pb ages and Hf isotopic signatures for magmatic and detrital zircons from the Tarim Craton reveal a distinct change in subduction style during the *** subduction cycle is recorded in increasing and decreasing intensity of subduction-related magmatic rocks and time-equivalent sedimentary successions,and converse trends ofεHf(t)values and corresponding changes in crustal incubation *** trends are consistent with a switch from advancing to retreating *** switch likely occurred at ca.760 Ma when zirconεHf(t)values increase and crustal incubation times decrease following a transitional shift between 800 Ma and 760 Ma.A switch at this time is consistent with Rodinia breakup and may have resulted in the late Neoproterozoic Tarim rift *** long-lived(ca.500 Ma)subduction recorded in the Tarim Craton suggests the predominance of a top-down process for Rodinia breakup on this part of its margin.

关键词： Supercontinent breakup Top-down tectonics Rodinia Subduction U-Pb-Hf isotopes

Application of Density Functional Theoretic Descriptors to Quantitative Structure-Activity Relationships with Temperature Constrained Cascade Correlation Network Models of Nitrobenzene Derivatives

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Chemical Research in Chinese Universities 2006年第4期22卷 439-442页

作者： CUI Xiu-jun ZHANG Zhuo-yong YUAN Xing ZHANG Jing-ping LIU Si-dong GUO Li-ping Peter de B. HARRINGTON Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China Department of Chemistry Capital Normal University Beijing 100037 P. R. China College of Urban and Environmental Science Northeast Normal University Changchun 130024 P. R. China Center for Intelligent Chemical Instrumentation Clippinger Laboratories Department of Chemistry and Biochemistry Ohio University Athens OH 45701-2979 USA

A temperature-constrained cascade correlation network （TCCCN）, a back-propagation neural network （BP）, and multiple linear regression（MLR） models were applied to quantitative structure-activity relationship（QSAR） modeling, on the basis of a set of 35 nitrobenzene derivatives and their acute toxicities. These structural quantum-chemical descriptors were obtained from the density functional theory（DFT）. Stepwise multiple regression analysis was performed and the model was obtained. The value of the calibration correlation coefficient R is 0. 925, and the value of cross-validation correlation coefficient R is 0. 87. The standard error S = 0. 308 and the cross-validated （ leave-one- out） standard error Scv =0. 381. Principal component analysis（PCA） was carried out for parameter selection. RMS errors for training set via TCCCN and BP are 0. 067 and 0. 095, respectively, and RMS errors for testing set via TCCCN and BP are 0. 090 and 0. 111, respectively. The results show that TCCCN performs better than BP and MLR.

关键词： DFT MLR PCA BP TCCCN QSAR Nitrobenzene derivative

太赫兹时域光谱结合主成分分析线性判别和支持向量机用于大黄样品鉴定（英文）

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光谱学与光谱分析 2017年第5期37卷 1606-1611页

作者：汪景荣张卓勇杨玉平相玉红 Peter de B.HARRINGTON 首都师范大学化学系北京100048 中央民族大学理学院北京100081 Center for Intelligent Chemical Instrumentation Clippinger LaboratoriesDepartment of Chemistry and BiochemistryOhio University

太赫兹时域光谱技术(THz-TDS)结合主成分分析-线性判别分析(PCA-LDA)和支持向量机(SVM)用于正品大黄样品的鉴定。在时域测量41个大黄样品的太赫兹时域透射光谱,然后将这些时域信号转换成频域的吸收系数系数。根据样本的吸收系数建立了... 详细信息

太赫兹时域光谱技术(THz-TDS)结合主成分分析-线性判别分析(PCA-LDA)和支持向量机(SVM)用于正品大黄样品的鉴定。在时域测量41个大黄样品的太赫兹时域透射光谱,然后将这些时域信号转换成频域的吸收系数系数。根据样本的吸收系数建立了主成分分析-线性判别分析和支持向量机的定性分类模型,并对正品和非正品大黄样本的分类模型进行了交叉验证。模型的预测能力和稳定性使用自助拉丁配分进行评价,使用50次自助拉丁配分,配分数为4。使用主成分分析-线性判别分析和支持向量机均得到了满意的结果。提出的方法证明是一种方便、无污染、准确和无需化学处理的鉴定大黄样本的方法。该文提出的步骤可以应用于其他中草药分类和生产的质量控制。

关键词：主成分分析-线性判别分析支持向量机太赫兹时域光谱大黄