The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various ...The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various alloys.Thirteen old Indian coins in different years of circulation,(1922–1986)were selected for the study.The concentrations were determined by Calibration free LIBS(CF-LIBS)method.The concentration of cuprum(Cu)is negligible,and aluminum(Al)is maximum in the first five coins,and vice-versa in the remaining eight coins.Two different multivariate methods,Principal Component Analysis(PCA)and Soft Independent Modelling of Class Analogy(SIMCA)have been used to classify and identify the coins.PCA classified all thirteen samples into four main alloy categories.The discernment of unknown samples to their probable class membership of alloy was performed using SIMCA.The surface hardness(Brinell hardness number)is linearly correlated with the plasma temperature and LIBS intensity ratios.The sample surface of the first and fifth coin belongs to Al-alloy,having the least surface hardness,and it became harder for Cu–Ni alloy,Ni-brass alloy,and bronze alloy.The hardness of the surface is more for bronze sample twelve.It is also observed that the plasma temperature increases monotonically with the Brinell hardness number.This analysis provides valuable information on fabrication methodology and explains large diversification in the elementary composition of old coins.展开更多
Let S be the set of n coins,in which there are m counterfeit coins, heavier (or lighter) than the normals. How many weighings do we need to find the m fakes by a balance? Denote by g_m(n) the least number of weighings...Let S be the set of n coins,in which there are m counterfeit coins, heavier (or lighter) than the normals. How many weighings do we need to find the m fakes by a balance? Denote by g_m(n) the least number of weighings we need.展开更多
As prior researchers have suggested,a firm’s success in an international market depends on how well its strategy fits the nonmarket environment,such as formal institutions.This paper examines the determinants of form...As prior researchers have suggested,a firm’s success in an international market depends on how well its strategy fits the nonmarket environment,such as formal institutions.This paper examines the determinants of formal institutions around new areas of economic activities.Specifically,we propose a framework for understanding how the quality of formal institutions in promoting entrepreneurship drives the focus of such institutions concerning initial coin offering(ICO),which is emerging as a popular fundraising method.The paper uses inductive analysis to examine how nonmarket factors—such as a jurisdiction’s tax haven nature,regulators’perceptions of ICOs as threats to national or political interests,and trade and industry associations—might moderate the relationship between the quality of institutions and the focus of such institutions regarding ICOs.One of this study’s key findings is that an economy’s quality of entrepreneurship-related institutions,perceived threats to national/political interests,and tax haven nature lead to different policy orientations.Consequently,regulators assign different importance when promoting crypto-entrepreneurship and dealing with associated risks.Regulators focusing mainly on promoting crypto-ventures have taken measures to enrich the blockchain ecosystem and provided tax and non-tax incentives to attract such ventures.Regulators focusing mainly on dealing with crypto-venture risks rely on a regulatory sandbox and close regulatory monitoring of such ventures.展开更多
The paper is entitled“Coinage in Akan Among Senior High School Students”.It aims to investigate coinage used by senior high school students.This paper also investigates other word formation processes involved in coi...The paper is entitled“Coinage in Akan Among Senior High School Students”.It aims to investigate coinage used by senior high school students.This paper also investigates other word formation processes involved in coined words and the reasons why the students use them in their everyday conversation.The collected data from direct elicitation and interviews were categorized into the types of coined words and analyzed in terms of their formation processes by using a method of analysis based on theories as proposed by Yule(1985),Potter(1975),O’Grady and Guzman(1996),and Gerber(1968).The findings show that there are 10 groups of word formation processes in this study.This paper presents a qualitative analysis of the findings of a sociolinguistic survey geared towards coinage as used by students of both Osei Tutu Senior High School and Bisease Community/Senior High School speech communities.It is also imperative to state that these two schools are located in typical Akan speaking communities.Osei Tutu Senior High School,situated in Akropong,in the Ashanti region of Ghana,is a single sex school(boys’school)and Bisease Community/Senior High School on the other hand is situated in Ajumako-Bisease in the central region.The latter is a mixed school.展开更多
On 26^th Feb. 2014, the biggest Bitcoin trading platform all over the world was offline. It was bankrupt due to data theft. Global Bitcoin players got into a panic. Is Bitcoinpromising？ Below I will analyze this ques...On 26^th Feb. 2014, the biggest Bitcoin trading platform all over the world was offline. It was bankrupt due to data theft. Global Bitcoin players got into a panic. Is Bitcoinpromising？ Below I will analyze this question on several aspects, which are Bitcoins＇ traits, demerits, and contrasts.展开更多
This article aims to make a brief presentation on the elements of material culture in the ancient Palestinian region,mainly coins,which were removed from their production context and placed in funerary contexts(coins ...This article aims to make a brief presentation on the elements of material culture in the ancient Palestinian region,mainly coins,which were removed from their production context and placed in funerary contexts(coins were often buried in graves),thus converted in amulets,acquiring magical and apotropaic senses.We will use examples verified in different parts of the Roman Empire,as in Pithekússai(modest island,which is in the Italian Peninsula),on the banks of the Thames,in Celtic contexts,more specifically in the current city of Lezoux,France,in the ancient city of Aquincum,present day Budapest,also in Tel Maresha and Tiberias,present-day Israel,to demonstrate how these practices were recurrent throughout the Empire.It is also our intention to observe iconographic elements that bring apotropaic content in their formulations,because,in addition to the role that coins could play in connecting the worlds of men and gods,many people believed that they had the power to project magical and apotropaic strength through images powerful that they portrayed.展开更多
Foreign body ingestion in children is considered an emergency. The most common ingested foreign bodies are coins;however, the ingestion of disc batteries is on the rise requiring urgent rigid esophagoscopy. In the lit...Foreign body ingestion in children is considered an emergency. The most common ingested foreign bodies are coins;however, the ingestion of disc batteries is on the rise requiring urgent rigid esophagoscopy. In the literature, multiple foreign body ingestion is very rare and only a few cases of multiple coins and multiple battery ingestion have been reported in the past. Herein, a case of simultaneous coin and battery ingestion requiring foreign bodies removal on two sequential endoscopies due to improper initial evaluation in a pediatric patient is reported which, to our knowledge, is the first reported case.展开更多
Foreign body ingestion is a common emergency situation in children with one or a few objects having been ingested. Here we report our experience using endo-scopic retrieval in a female centenarian with dyspnea and for...Foreign body ingestion is a common emergency situation in children with one or a few objects having been ingested. Here we report our experience using endo-scopic retrieval in a female centenarian with dyspnea and foreign bodies in the esophagus. She attempted suicide by swallowing 26 coins and two other foreign bodies. A gastroscope was used to remove all foreign bodies in the lower esophagus. In total, 26 coins, one ferrous ring and one cylindrical plastic object were retrieved. To our knowledge, this is the first clinical report on retrieval of so many foreign bodies in a single case.展开更多
A symmetric all-organic non-aqueous redox flow-type battery was investigated employing the neutral small molecule radical 3-phenyl-1,5-di-p-tolylverdazyl,which can be reversibly oxidized and reduced in one-electron pr...A symmetric all-organic non-aqueous redox flow-type battery was investigated employing the neutral small molecule radical 3-phenyl-1,5-di-p-tolylverdazyl,which can be reversibly oxidized and reduced in one-electron processes,as the sole charge storage material.Cyclic voltammetry of the verdazyl radical in 0.5 M tetrabutylammonium hexa fluoro phosphate(TBAPF6)in acetonitrile revealed redox couples at-0.17 V and-1.15 V vs.Ag+/Ag,leading to a theoretical cell voltage of 0.98 V.From the dependence of peak currents on the square root of the scan rate,diffusion coefficients on the order of 4 x 10 6 cm2 s-1 were demonstrated.Cycling performance was assessed in a static cell employing a Tokoyuma AHA anion exchange membrane,with 0.04 M verdazyl as catholyte and anolyte in 0.5 M TBAPF6 in acetonitrile at a current density of 0.12 mA cm-2.Although coulombic efficiencies were good(94%-97%)throughout the experiment,the capacity faded gradually from high initial values of 93%of the theoretical discharge capacity to 35%by the 50th cycle.Voltage and energy efficiencies were 68%and 65%,respectively.Postcycling analysis by cyclic voltammetry revealed that decomposition of the active material with cycling is a leading cause of cell degradation.展开更多
A capacity increase is often observed in the early stage of Li-ion battery cycling.This study explores the phenomena involved in the capacity increase from the full cell,electrodes,and materials perspective through a ...A capacity increase is often observed in the early stage of Li-ion battery cycling.This study explores the phenomena involved in the capacity increase from the full cell,electrodes,and materials perspective through a combination of non-destructive diagnostic methods in a full cell and post-mortem analysis in a coin cell.The results show an increase of 1%initial capacity for the battery aged at 100%depth of discharge(DOD)and 45℃.Furthermore,large DODs or high temperatures accelerate the capacity increase.From the incremental capacity and differential voltage(IC-DV)analysis,we concluded that the increased capacity in a full cell originates from the graphite anode.Furthermore,graphite/Li coin cells show an increased capacity for larger DODs and a decreased capacity for lower DODs,thus in agreement with the full cell results.Post-mortem analysis results show that a larger DOD enlarges the graphite dspace and separates the graphite layer structure,facilitating the Li+diffusion,hence increasing the battery capacity.展开更多
文摘The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various alloys.Thirteen old Indian coins in different years of circulation,(1922–1986)were selected for the study.The concentrations were determined by Calibration free LIBS(CF-LIBS)method.The concentration of cuprum(Cu)is negligible,and aluminum(Al)is maximum in the first five coins,and vice-versa in the remaining eight coins.Two different multivariate methods,Principal Component Analysis(PCA)and Soft Independent Modelling of Class Analogy(SIMCA)have been used to classify and identify the coins.PCA classified all thirteen samples into four main alloy categories.The discernment of unknown samples to their probable class membership of alloy was performed using SIMCA.The surface hardness(Brinell hardness number)is linearly correlated with the plasma temperature and LIBS intensity ratios.The sample surface of the first and fifth coin belongs to Al-alloy,having the least surface hardness,and it became harder for Cu–Ni alloy,Ni-brass alloy,and bronze alloy.The hardness of the surface is more for bronze sample twelve.It is also observed that the plasma temperature increases monotonically with the Brinell hardness number.This analysis provides valuable information on fabrication methodology and explains large diversification in the elementary composition of old coins.
文摘Let S be the set of n coins,in which there are m counterfeit coins, heavier (or lighter) than the normals. How many weighings do we need to find the m fakes by a balance? Denote by g_m(n) the least number of weighings we need.
文摘As prior researchers have suggested,a firm’s success in an international market depends on how well its strategy fits the nonmarket environment,such as formal institutions.This paper examines the determinants of formal institutions around new areas of economic activities.Specifically,we propose a framework for understanding how the quality of formal institutions in promoting entrepreneurship drives the focus of such institutions concerning initial coin offering(ICO),which is emerging as a popular fundraising method.The paper uses inductive analysis to examine how nonmarket factors—such as a jurisdiction’s tax haven nature,regulators’perceptions of ICOs as threats to national or political interests,and trade and industry associations—might moderate the relationship between the quality of institutions and the focus of such institutions regarding ICOs.One of this study’s key findings is that an economy’s quality of entrepreneurship-related institutions,perceived threats to national/political interests,and tax haven nature lead to different policy orientations.Consequently,regulators assign different importance when promoting crypto-entrepreneurship and dealing with associated risks.Regulators focusing mainly on promoting crypto-ventures have taken measures to enrich the blockchain ecosystem and provided tax and non-tax incentives to attract such ventures.Regulators focusing mainly on dealing with crypto-venture risks rely on a regulatory sandbox and close regulatory monitoring of such ventures.
文摘The paper is entitled“Coinage in Akan Among Senior High School Students”.It aims to investigate coinage used by senior high school students.This paper also investigates other word formation processes involved in coined words and the reasons why the students use them in their everyday conversation.The collected data from direct elicitation and interviews were categorized into the types of coined words and analyzed in terms of their formation processes by using a method of analysis based on theories as proposed by Yule(1985),Potter(1975),O’Grady and Guzman(1996),and Gerber(1968).The findings show that there are 10 groups of word formation processes in this study.This paper presents a qualitative analysis of the findings of a sociolinguistic survey geared towards coinage as used by students of both Osei Tutu Senior High School and Bisease Community/Senior High School speech communities.It is also imperative to state that these two schools are located in typical Akan speaking communities.Osei Tutu Senior High School,situated in Akropong,in the Ashanti region of Ghana,is a single sex school(boys’school)and Bisease Community/Senior High School on the other hand is situated in Ajumako-Bisease in the central region.The latter is a mixed school.
文摘On 26^th Feb. 2014, the biggest Bitcoin trading platform all over the world was offline. It was bankrupt due to data theft. Global Bitcoin players got into a panic. Is Bitcoinpromising？ Below I will analyze this question on several aspects, which are Bitcoins＇ traits, demerits, and contrasts.
文摘This article aims to make a brief presentation on the elements of material culture in the ancient Palestinian region,mainly coins,which were removed from their production context and placed in funerary contexts(coins were often buried in graves),thus converted in amulets,acquiring magical and apotropaic senses.We will use examples verified in different parts of the Roman Empire,as in Pithekússai(modest island,which is in the Italian Peninsula),on the banks of the Thames,in Celtic contexts,more specifically in the current city of Lezoux,France,in the ancient city of Aquincum,present day Budapest,also in Tel Maresha and Tiberias,present-day Israel,to demonstrate how these practices were recurrent throughout the Empire.It is also our intention to observe iconographic elements that bring apotropaic content in their formulations,because,in addition to the role that coins could play in connecting the worlds of men and gods,many people believed that they had the power to project magical and apotropaic strength through images powerful that they portrayed.
文摘Foreign body ingestion in children is considered an emergency. The most common ingested foreign bodies are coins;however, the ingestion of disc batteries is on the rise requiring urgent rigid esophagoscopy. In the literature, multiple foreign body ingestion is very rare and only a few cases of multiple coins and multiple battery ingestion have been reported in the past. Herein, a case of simultaneous coin and battery ingestion requiring foreign bodies removal on two sequential endoscopies due to improper initial evaluation in a pediatric patient is reported which, to our knowledge, is the first reported case.
文摘Foreign body ingestion is a common emergency situation in children with one or a few objects having been ingested. Here we report our experience using endo-scopic retrieval in a female centenarian with dyspnea and foreign bodies in the esophagus. She attempted suicide by swallowing 26 coins and two other foreign bodies. A gastroscope was used to remove all foreign bodies in the lower esophagus. In total, 26 coins, one ferrous ring and one cylindrical plastic object were retrieved. To our knowledge, this is the first clinical report on retrieval of so many foreign bodies in a single case.
基金supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada (C. A. D.: DG, 04279 J. B. G.: DG, 435675 and S. M. B.: CGS D scholarship)+1 种基金support form the Canada Foundation for Innovation (CFI) the New Brunswick Innovation Foundation (NBIF)the University of New Brunswick. J. B. G. would like to thank the University of Western Ontario for support
文摘A symmetric all-organic non-aqueous redox flow-type battery was investigated employing the neutral small molecule radical 3-phenyl-1,5-di-p-tolylverdazyl,which can be reversibly oxidized and reduced in one-electron processes,as the sole charge storage material.Cyclic voltammetry of the verdazyl radical in 0.5 M tetrabutylammonium hexa fluoro phosphate(TBAPF6)in acetonitrile revealed redox couples at-0.17 V and-1.15 V vs.Ag+/Ag,leading to a theoretical cell voltage of 0.98 V.From the dependence of peak currents on the square root of the scan rate,diffusion coefficients on the order of 4 x 10 6 cm2 s-1 were demonstrated.Cycling performance was assessed in a static cell employing a Tokoyuma AHA anion exchange membrane,with 0.04 M verdazyl as catholyte and anolyte in 0.5 M TBAPF6 in acetonitrile at a current density of 0.12 mA cm-2.Although coulombic efficiencies were good(94%-97%)throughout the experiment,the capacity faded gradually from high initial values of 93%of the theoretical discharge capacity to 35%by the 50th cycle.Voltage and energy efficiencies were 68%and 65%,respectively.Postcycling analysis by cyclic voltammetry revealed that decomposition of the active material with cycling is a leading cause of cell degradation.
基金supported by a grant from the China Scholarship Council(202006370035 and 202006220024)supported by the National Natural Science Foundation of China(52107229)。
文摘A capacity increase is often observed in the early stage of Li-ion battery cycling.This study explores the phenomena involved in the capacity increase from the full cell,electrodes,and materials perspective through a combination of non-destructive diagnostic methods in a full cell and post-mortem analysis in a coin cell.The results show an increase of 1%initial capacity for the battery aged at 100%depth of discharge(DOD)and 45℃.Furthermore,large DODs or high temperatures accelerate the capacity increase.From the incremental capacity and differential voltage(IC-DV)analysis,we concluded that the increased capacity in a full cell originates from the graphite anode.Furthermore,graphite/Li coin cells show an increased capacity for larger DODs and a decreased capacity for lower DODs,thus in agreement with the full cell results.Post-mortem analysis results show that a larger DOD enlarges the graphite dspace and separates the graphite layer structure,facilitating the Li+diffusion,hence increasing the battery capacity.
