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journal of Analysis and Testing 2023年第1期7卷 25-32页

作者： Keane j.Tao Micah D.Castleman shiquan Tao Princess Ann High school 4400 Virginia Beach BlvdVirginia BeachVA 23462USA Department of Chemistry and Physics West Texas A&M UniversityBox 60732CanyonTX 79016USA

In this work,a field-applicable,simple method for quick detecting chlorogenic acid(CGA)was *** method is based on CGA’s antioxidant *** is reported to reduce a mixture solution of FeCl_(3)/K_(3)Fe(CN)_(6)to generate Fe_(4)[Fe(CN)_(6)]_(3),the Prussian blue,in an aqueous *** reaction was adopted in this work by using solid-ink printed annuli on a filter-paper as reaction *** reagent is pre-loaded and dried within the solid ink printed *** a field test,a drop of a sample solution is directly applied to a reagent-loaded *** reaction product within the circle shows a blue color,which is detected by using an iPad(or cellphone)camera as a detector and a light-emitting diode flashlight lamp as a light source.A freely available RGB colorimeter program from Apple store was used to read light intensity of three colors:red,green,blue,and absorbance signal of red and blue light is *** difference of absorbance signal of red light from that of blue light was found having linear relationship with CGA concentration in an aqueous sample *** simple method is sensitive with a detection limit of 1.0μg/mL for CGA in sample *** technique was used to analyze CGA concentration in green coffee extract,and the analytical results agree well with that obtained using a UV/Vis absorption spectrometric *** real sample test results demonstrate the usefulness of this simple method for quick detecting CGA in green coffee extract products in field test applications.

关键词： Chlorogenic acid Paper based analytical device FeCl_(3)/K_(3)Fe(CN)_(6)·iPad colorimetry Green coffee extract

Identification of stable adsorption sites and diffusion paths on nanocluster surfaces:an automated scanning algorithm

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npj Computational Materials 2019年第1期5卷 246-253页

作者： Tibor szilvási Benjamin W.j.Chen Manos Mavrikakis Department of Chemical&Biological Engineering University of Wisconsin-Madison1415 Engineering DriveMadisonWI 53706USA

The diverse coordination environments on the surfaces of discrete,three-dimensional(3D)nanoclusters contribute significantly to their unique catalytic *** the numerous adsorption sites and diffusion paths on these clusters is however tedious and time-consuming,especially for large,asymmetric ***,we present a simple,automated method for constructing approximate 2D potential energy surfaces for the adsorption of atomic species on the surfaces of 3D nanoclusters with minimal human *** potential energy surfaces fully characterize the important adsorption sites and diffusion paths on the nanocluster surfaces with accuracies similar to current approaches and at comparable computational *** method can treat complex nanoclusters,such as alloy nanoclusters,and accounts for cluster relaxation and adsorbate-induced reconstruction,important for obtaining accurate ***,its highly parallelizable nature is ideal for modern supercomputer architectures.

关键词： properties adsorption cluster

Estimation of ship Emission of Ocean-going Vessels in Hong Kong

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Estimation of Ship Emission of Ocean-going Vessels in Hong K...

Rapid climate change-induced collapse of hunter-gatherer societies in the lower Mississippi River valley between ca. 3300 and 2780 cal yr BP

第十届全国气溶胶会议暨第六届海峡两岸气溶胶技术研讨会

作者： P.s.Yau s.C.Lee james.j.Corbett K.F.Ho Department of Civil and structural Engineering Research Center for Environmental Technology and ManagementThe Hong Kong Polytechnic UniversityHung Hom College of Marine and Earth studies University of DelawareRobinson HallNewark

Hong Kong is known as one of the major international maritime centres in the *** with huge engines running on marine fuel may cause air quality impact influencing local *** was reported by HKEPD that ships contributed 5%,18%,9% 1% and 3% of sO2,NOx,PM10,VOC and CO local emission in *** this study,ocean-going vessel emission in Hong Kong in 2007 was estimated by an activity based *** emissions were estimated as a function of vessel power demand(kW-hr) and emission factor(g/kW-hr).The waterway network model was used to geographically and temporally characterize ship traffic on the basis of a navigation network,ship activity data,and a ship attributes *** for each trip were estimated and then aggregated to generate the overall ocean-going vessel *** emissions of different kinds of pollutants(sO2,NOx,CO2 CO,HC and PM) from the ocean-going vessels were estimated by this *** container vessels followed by passenger vessels contributed the most to the OGV emission in Hong Kong.

关键词： ship emission Ocean-going vessel Air pollution

来源： cnki会议评论

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science China Earth sciences 2018年第2期61卷 178-189页

作者： tristram r.kidder edward r.henry lee j.arco Department of Anthropology Washington University in St. Louis St. Louis 63130 USA Geoarehaeology Laboratory Washington University in St. Louis St. Louis 63130 USA GAI Consultants Inc. Homestead PA 15120 USA Teaching and Experimental Center for Archaeology and Cultural Heritage Protection Henan University Kaifeng 475001 China

Hunter-gatherer communities in the American southeast reached an apogee of social and political complexity in the period between ca. 4200 and 3000 cal yr BP. In the lower Mississippi Valley(LMV) the Poverty Point culture defined this period of socio-political elaboration. However, following a significant period of climate change that led to exceptional flooding and a major reorganization of the course of the Mississippi River, this culture collapsed beginning ca. 3300–3200 cal yr BP and the LMV was abandoned for the subsequent 500 years. In this study, we use data from the jaketown site in the Yazoo Basin of west-central Mississippi to refine the chronology of the climate event that caused the collapse of the Poverty Point culture. A large flood buried Poverty Point-era occupation deposits at jaketown around 3310 cal yr BP. Lateral migration of the Mississippi River during flooding led to inundation of the Yazoo Basin and re-occupation of ancient river courses. A coarse sand stratum topped by a more than a meter-thick fining upward sediment package marks a crevasse deposit caused by a rupture of the natural levee at jaketown. This levee breach was part of a larger pattern of erratic flooding throughout the LMV and is associated with major landscape evolution and the abandonment of Poverty Point sites within the valley. Early Woodland peoples re-colonized the crevasse surface after ca. 2780 cal yr BP. Following this event, the jaketown site and the eastern Yazoo Basin witnessed a period of landscape stability that lasts to this day. These archaeological data demonstrate how climate change and natural disasters can lead to socio-political dissolution and reorganization even in relatively small-scale hunter-gatherer populations.

关键词： Rapid climate change Hunter-gatherers Flooding Mississippi River Valley Poverty Point jaketown site

Correlation of MRI-determined small bowel Crohn’s disease categories with medical response and surgical pathology

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World journal of Gastroenterology 2009年第27期15卷 3367-3375页

作者： Ian Craig Lawrance Christopher j Welman Peter shipman Kevin Murray school of Medicine and Pharmacology University of Western AustraliaFremantle Hospital WA 6160 Australia Department of Gastroenterology Fremantle Hospital WA 6160 Australia Department of Radiology Fremantle Hospital WA 6160 Australia statistical Consulting Group School of Mathematics and Statistics University of Western AustraliaWA 6160 Australia

AIM: To determine whether magnetic resonance imaging (MRI) can be used to categorize small bowel Crohn's disease (sB CD) into groups that correlate with response to medical therapy and surgical ***: Data was collected from all patients with MRI evidence of sB CD without significant colonic disease over a 32-mo period. Two radiologists, blinded to clinical findings, evaluated each MRI and grouped them based on bowel wall thickness and wall enhancement. These categories were: (1) "fibrosis", (2) "mild segmental hyper-enhancement and mild wall thickening", (3) "mild segmental hyper-enhancement and marked wall thickening", (4) "marked segmental transmural hyper-enhancement". Patient response to additional medical therapy post-MRI was prospectively determined at 8-wk. Non-responders underwent endoscopy and were offered therapeutic endoscopy or surgery. surgical pathology was assessed against the MRI category. REsULTs: Fifty-five patients were included. Females and category "2" patients were more likely, and patients with luminal narrowing and hold-up less likely, to respond to medical therapy (P seventeen patients underwent surgery. The surgical pathologicalfindings of fibrosis and the severity of inflammation correlated with the MRI category in all ***: Our fi ndings suggest that sB CD can be grouped by the MRI f indings and that these groups are associated with patients more likely to respond to continued medical therapy. The MRI categories also correlated with the presence and level of intestinal inflammation and fibrosis on surgical pathology, and may be of prognostic use in the management of CD patients.

关键词： Magnetic resonance imaging Crohn's disease Fibrosis Prognosis Pathology

Citizen sensors or extreme publics? Transparency and accountability interventions on the mobile geoweb

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International journal of Digital Earth 2014年第7期7卷 516-533页

作者： Y.Georgiadou j.H.Lungo C.Richter Faculty of Geo-information science and Earth Observation(ITC) University TwenteEnschedeThe Netherlands College of Information and Communication Technologies(CoICT) University Dar es SalaamDar es SalaamTanzania

Transparency and Accountability(T&A)interventions are emergent social technologies in middle and low-income *** bring together citizen sensors,mobile communications,geo-browsers and social organization to raise public awareness on the extent of governance deficits,and monitor government’s(in)*** to their novelty,almost all we know about the effectiveness of T&A interventions comes from gray *** citizen sensors radically increase the transparency of the state,or are changes brought about by T&A interventions more likely to be incremental?We review the literature on transparency policies and describe their drivers,characteristics and supply-demand *** discuss promising cases of T&A interventions in East Africa,the empirical focus of an on-going collaborative research *** conclude that the effect of T&A interventions is more likely to be incremental and mediated by existing organizations and professional users who populate the space between the state and *** elements at the interface between supply and demand seem rather crucial for designers of T&A interventions:accountability-relevant data and extreme publics.

关键词： citizen sensors transparency accountability-relevant data extreme publics mobile geoweb

Performance of LHAAsO-WCDA and observation of the Crab Nebula as a standard candle

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Chinese Physics C 2021年第8期45卷 166-181页

作者： F.Aharonian Q.An Axikegu L.X.Bai Y.X.Bai Y.W.Bao D.Bastieri X.j.Bi Y.j.Bi H.Cai j.T.Cai Z.Cao Z.Cao j.Chang j.F.Chang X.C.Chang B.M.Chen j.Chen L.Chen L.Chen L.Chen M.j.Chen M.L.Chen Q.H.Chen s.H.Chen s.Z.Chen T.L.Chen X.L.Chen Y.Chen N.Cheng Y.D.Cheng s.W.Cui X.H.Cui Y.D.Cui B.Z.Dai H.L.Dai Z.G.Dai Danzengluobu D.della Volpe B.D'Ettorre Piazzoli X.j.Dong j.H.Fan Y.Z.Fan Z.X.Fan j.Fang K.Fang C.F.Feng L.Feng s.H.Feng Y.L.Feng B.Gao C.D.Gao Q.Gao W.Gao M.M.Ge L.s.Geng G.H.Gong Q.B.Gou M.H.Gu j.G.Guo X.L.Guo Y.Q.Guo Y.Y.Guo Y.A.Han H.H.He H.N.He j.C.He s.L.He X.B.He Y.He M.Heller Y.K.Hor C.Hou X.Hou H.B.Hu s.Hu s.C.Hu X.j.Hu D.H.Huang Q.L.Huang W.H.Huang X.T.Huang Z.C.Huang F.ji X.L.ji H.Y.jia K.jiang Z.j.jiang C.jin D.Kuleshov K.Levochkin B.B.Li C.Li C.Li F.Li H.B.Li H.C.Li H.Y.Li j.Li K.Li W.L.Li X.Li X.Li X.R.Li Y.Li Y.Z.Li Z.Li Z.Li E.W.Liang Y.F.Liang s.j.Lin B.Liu C.Liu D.Liu H.Liu H.D.Liu j.Liu j.L.Liu j.s.Liu j.Y.Liu M.Y.Liu R.Y.Liu s.M.Liu W.Liu Y.N.Liu Z.X.Liu W.j.Long R.Lu H.K.Lv B.Q.Ma L.L.Ma X.H.Ma j.R.Mao A.Masood W.Mitthumsiri T.Montaruli Y.C.Nan B.Y.Pang P.Pattarakijwanich Z.Y.Pei M.Y.Qi B.Q.Qiao D.Ruffolo V.Rulev A.saiz L.shao O.shchegolev X.D.sheng j.R.shi H.C.song Yu.V.stenkin V.stepanov Q.N.sun X.N.sun Z.B.sun P.H.T.Tam Z.B.Tang W.W.Tian B.D.Wang C.Wang H.Wang H.G.Wang j.C.Wang j.s.Wang L.P.Wang L.Y.Wang R.N.Wang W.Wang W.Wang X.G.Wang X.j.Wang X.Y.Wang Y.D.Wang Y.j.Wang Y.P.Wang Z.Wang Z.Wang Z.H.Wang Z.X.Wang D.M.Wei j.j.Wei Y.j.Wei T.Wen C.Y.Wu H.R.Wu s.Wu W.X.Wu X.F.Wu s.Q.Xi j.Xia j.j.Xia G.M.Xiang G.Xiao H.B.Xiao G.G.Xin Y.L.Xin Y.Xing D.L.Xu R.X.Xu L.Xue D.H.Yan C.W.Yang F.F.Yang j.Y.Yang L.L.Yang M.j.Yang R.Z.Yang s.B.Yang Y.H.Yao Z.G.Yao Y.M.Ye L.Q.Yin N.Yin X.H.You Z.Y.You Y.H.Yu Q.Yuan H.D.Zeng T.X.Zeng W.Zeng Z.K.Zeng M.Zha X.X.Zhai B.B.Zhang H.M.Zhang H.Y.Zhang j.L.Zhang j.W.Zhang L.Zhang L.Zhang L.X.Zhang P.F.Zhang P.P.Zhang R.Zhang s.R.Zhang s.s.Zhang X.Zhang X.P.Zhang Y.Zhang Y.Zhang Y.F.Zhang Y.L.Zhang B.Zhao j.Zhao L.Zhao L.Z.Zhao s.P.Zhao F.Zheng Y.Zheng B.Zhou H.Zhou j.N.Zhou Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of sciences Beijing 100049China TIANFU Cosmic Ray Research Center ChengduSichuanChina state Key Laboratory of Particle Detection and Electronics China University of science and Technology of China Hefei 230026China Department of Engineering Physics Tsinghua UniversityBeijing 100084China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China National space science Center Chinese Academy of SciencesBeijing 100190China school of Physics Peking UniversityBeijing 100871China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China school of Physics and Astronomy&school of Physics(Guangzhou) Sun Yat-sen UniversityZhuhai 519082China school of Physical science and Technology Guangxi UniversityNanning 530004China Hebei Normal University Shijiazhuang 050024China school of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China school of Astronomy and space science Nanjing UniversityNanjing 210023China Key Laboratory of Dark Matter and space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Institute of Frontier and Interdisciplinary science Shandong UniversityQingdao 266237China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Tsung-Dao Lee Institute&school of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China school of Physical science and Technology&school of Information science and Technology Southwest Jiaotong UniversityChengdu 610031China College of Physics Sichuan UniversityChengdu 610065China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China school of Physics and Technology Wuhan UniversityWuhan 430072China school of Physics and Astronomy Yunnan University

The first Water Cherenkov detector of the LHAAsO experiment(WCDA-1)has been operating since April *** data for the first year have been analyzed to test its performance by observing the Crab Nebula as a standard *** WCDA-1 achieves a sensitivity of 65 mCU per year,with a statistical threshold of 5 *** accomplish this,a 97.7%cosmic-ray background rejection rate around 1 TeV and 99.8%around 6 TeV with an ap proximate photon acceptance of 50%is achieved after applying an algorithm to separate gamma-induced *** angular resolution is measured using the Crab Nebula as a point source to be approximately 0.45°at 1 TeV and better than 0.2°above 6 TeV,with a pointing accuracy better than 0.05°.These values all match the design *** energy resolution is found to be 33%for gamma rays around 6 *** spectral energy distribution of the Crab Nebula in the range from 500 GeV to 15.8 TeV is measured and found to be in agreement with the results from other TeV gamma ray observatories.

关键词： LHAAsO-WCDA Crab Nebula angular resolution spectral energy distribution

Implementation of distortion symmetry for the nudged elastic band method with DisPy

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npj Computational Materials 2019年第1期5卷 685-693页

作者： jason M.Munro Vincent s.Liu Venkatraman Gopalan Ismaila Dabo Department of Materials science and Engineering and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Penn state Institutes of Energy and the Environment The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Physics The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Engineering science and Mechanics The Pennsylvania State UniversityUniversity ParkPA 16802USA

The nudged elastic band(NEB)method is a commonly used approach for the calculation of minimum energy pathways of kinetic ***,the final paths obtained rely heavily on the nature of the initially chosen *** often necessitates running multiple calculations with differing starting points in order to obtain accurate ***,it has been shown that the NEB algorithm can only conserve or raise the distortion symmetry exhibited by an initial *** this knowledge,symmetryadapted perturbations can be generated and used as a tool to systematically lower the initial path symmetry,enabling the exploration of other low-energy pathways that may ***,the group and representation theory details behind this process are presented and implemented in a standalone piece of software(DisPy).The method is then demonstrated by applying it to the calculation of ferroelectric switching pathways in LiNbO_(3).Previously reported pathways are more easily obtained,with new paths also being found which involve a higher degree of atomic coordination.

关键词： symmetry distortion details

Bank erosion in an Andean páramo river system: Implications for hydro-development and carbon dynamics in the neotropical Andes

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journal of Mountain science 2019年第2期16卷 243-255页

作者： Derek j.MARTIN Christopher ELY Beverley C.WEMPLE Department of Geography and Planning Appalachian State University Department of Geography University of Vermont

The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the páramo?s organic-rich soils. Little is known, however, about the hydro-geomorphic characteristics of the rivers that drain these ecosystems. With impending plans for widespread hydro-development and increasing implementation of carbon-sequestering compensation for ecosystem services programs in the region it is imperative that we develop a thorough understanding of the hydrogeomorphic role that rivers play in this unique ecosystem. The objective of this study was to quantify bank erosion along an Amazonian headwater stream draining a small, relatively undisturbed páramo catchment to gain a better understanding of the natural erosion regime and the resulting sediment contributions from this unique ecosystem. This study implemented a combination of field, laboratory, and Geographic Information systems techniques to quantify bank erosion rates and determine a bank erosion sediment yield from the Ningar River, a small páramo catchment(22.7 km^2) located in the eastern Andean cordillera of Ecuador. Results show that bank erosion rates range from 3.0 to ≥ 390.0 mm/yr, are highly episodic, and yield at least 487 tons of sediment annually to the Ningar River. These results imply that 1) páramo ecosystems substantially contribute to the sediment load of the Amazon River basin; 2) bank erosion is a potentially significant flux component of basin-scale carbon cycles in páramo ecosystems; and 3) hydrologic alteration campaigns(dam building) will likely critically alter these contributions and concomitantly disconnect a critical source of sediment and nutrients to downstream ecosystems.

关键词： Bank erosion Páramo Fluvial geomorphology Andes

Cysteine proteases as therapeutic targets:does selectivity matter? A systematic review of calpain and cathepsin inhibitors

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Acta Pharmaceutica sinica B 2015年第6期5卷 506-519页

作者： Marton siklos Manel Ben Aissa Gregory R.j.Thatcher Department of Medicinal Chemistry and Pharmacognosy University of Illinois College of Pharmacy

Cysteine proteases continue to provide validated targets for treatment of human *** neurodegenerative disorders,multiple cysteine proteases provide targets for enzyme inhibitors,notably caspases,calpains,and *** reactive,active-site cysteine provides specificity for many inhibitor designs over other families of proteases,such as aspartate and serine;however,a)inhibitor strategies often use covalent enzyme modification,and b)obtaining selectivity within families of cysteine proteases and their isozymes is *** review provides a general update on strategies for cysteine protease inhibitor design and a focus on cathepsin B and calpain 1 as drug targets for neurodegenerative disorders;the latter focus providing an interesting query for the contemporary assumptions that irreversible,covalent protein modification and low selectivity are anathema to therapeutic safety and efficacy.

关键词： Cysteine protease Calpain Cathepsin Enzyme inhibitors Neurodegeneration Alzheimer’s disease