Twenty Yongzheng copper coins were fast dating by X-ray energy dispersive spectrometer with scanning electron microscope(SEM-EDS)according to official ingredient.The 20 coins were classified in two groups according to...Twenty Yongzheng copper coins were fast dating by X-ray energy dispersive spectrometer with scanning electron microscope(SEM-EDS)according to official ingredient.The 20 coins were classified in two groups according to the results.Group 1 represents the coins minted before AD 1728 and group 2 represents the coins minted after AD 1728.At concentration range(0.00%–5.13%),the distribution of lead is not homogeneous in the coins,and the largest diameter of lead inclusion is less than 15μm.The official fineness degrade is supported.展开更多
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
Non-destructive analysis of some electrum coins from post Gupta period and of coins from different mints of Mughal emperors, Shahjahan and Aurangzeb, have been done by instrumental neutron activation analysis (INAA) u...Non-destructive analysis of some electrum coins from post Gupta period and of coins from different mints of Mughal emperors, Shahjahan and Aurangzeb, have been done by instrumental neutron activation analysis (INAA) using 252Cf neutron source. The elemental content of these coins are determined by comparator method by measuring the activities of the radioisotopes formed after (n,r) reactions, at their corresponding photopeaks. It is found that identified electrum coins contain copper as a major component and hence can be termed as cupro-electrum coins. As regards the analysis of coins from different mints there is no much variation in silver content while copper content varies from mint to mint. Coins from both the emperors are found to contain considerable amount of gold.展开更多
The radioactivity induced in the coins from Satvahanas,Ahmadshah Bahamani,Gujrat Sultan,Nizamshahi and Marathas after(n,γ) reactions for the elemeats of interest is measured on multichannel analyzer coupled to high p...The radioactivity induced in the coins from Satvahanas,Ahmadshah Bahamani,Gujrat Sultan,Nizamshahi and Marathas after(n,γ) reactions for the elemeats of interest is measured on multichannel analyzer coupled to high purity germanium detector and percentage of these elements is determined by comparator method of NAA.All these coins are found to be copper based with the presence of As,Sb,In,An,Sn and Mn.展开更多
We numerically study the effect of the quantum coins on the two-particle quantum walks on an infinite line. Both non-interacting and interacting particles are considered. The joint probability as well as the bunching ...We numerically study the effect of the quantum coins on the two-particle quantum walks on an infinite line. Both non-interacting and interacting particles are considered. The joint probability as well as the bunching or anti- bunching behavior are greatly affected by the phase factors in the coin operation. Further, the spatial correlation can be maximized by choosing appropriate coin parameters. The entanglement between the two particles can be adjusted in the same manner.展开更多
The dynamical and static disordered quantum walks were extensively studied recently. It is found that, for the dynamicM disorder case, the transport behavior of particles is diffusive, and for the static disorder ease...The dynamical and static disordered quantum walks were extensively studied recently. It is found that, for the dynamicM disorder case, the transport behavior of particles is diffusive, and for the static disorder ease the transport behavior is localized. In this work, we study the effect of quantum coins on the transport behaviors of the binary disordered quantum walks. We lind that once the coins satisfy certain conditions, the sub-ballistic spreading could be found in binary dynamical disorder quantum walks, and the sub-ballistic, diffusive and sub- diffusive spreadings could be found in binary static disorder quantum walks. We obtain the necessary conditions for those abnormal diffusive behaviors.展开更多
Non-fungible tokens(NFTs)are one-of-a-kind digital assets that are stored on a blockchain.Examples of NFTs include art(e.g.,image,video,animation),collectables(e.g.,autographs),and objects from games(e.g.,weapons and ...Non-fungible tokens(NFTs)are one-of-a-kind digital assets that are stored on a blockchain.Examples of NFTs include art(e.g.,image,video,animation),collectables(e.g.,autographs),and objects from games(e.g.,weapons and poisons).NFTs provide content creators and artists a way to promote and sell their unique digital material online.NFT coins underpin the ecosystems that support NFTs and are a new and emerging asset class and,as a new and emerging asset class,NFT coins are not immune to economic uncertainty.This research seeks to address the following questions.What is the time and frequency relationship between economic uncertainty and NFT coins?Is the relationship similar across different NFT coins?As an emerging asset,do NFT coins exhibit explosive behavior and if so,what role does economic uncertainty play in their formation?Using a new Twitter-based economic uncertainty index and a related equity market uncertainty index it is found that wavelet coherence between NFT coin prices(ENJ,MANA,THETA,XTZ)and economic uncertainty or market uncertainty is strongest during the periods January 2020 to July 2020 and January 2022 to July 2022.Periods of high significance are centered around the 64-day scale.During periods of high coherence,economic and market uncertainty exhibit an out of phase relationship with NFT coin prices.Network connectedness shows that the highest connectedness occurred during 2020 and 2022 which is consistent with the findings from wavelet analysis.Infectious disease outbreaks(COVID-19),NFT coin price volatility,and Twitter-based economic uncertainty determine bubbles in NFT coin prices.展开更多
RECENT findings on the East African coast confirm what many people have suspected for years： Trade between the Chinese and Africans existed long before Europeans stepped foot on the shores of East Africa＇s West Indi...RECENT findings on the East African coast confirm what many people have suspected for years： Trade between the Chinese and Africans existed long before Europeans stepped foot on the shores of East Africa＇s West Indian Ocean Coast.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
The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systema...The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systematic replacement of metallic structural support components(MSSCs)to minimize non-active constituent ratios,contingent upon maintaining robust interfacial contact integrity among electrodes,separators,and battery shells.Herein,we present a novel LPCC configuration employing solvent-free processed ultra-thick fluorinated carbon cathode(UCFxC)to achieve complete MSSCs elimination.The engineered UCFxC demonstrates exceptional areal capacity metrics(249.45 mg cm^(-2),215.77 m Ah cm^(-2)),enabling a 27.8% mass reduction compared with conventional laboratoryassembled coin cell while achieving 941.5% energy density enhancement through optimized electrode conductivity.Notably,single-walled carbon nanotube(SWCNT)-modified UCFxC architectures exhibited superior performance with energy exceeding 1.0 Wh at 50℃.This architectural paradigm provides valuable insights for developing next-generation high-energy-density LPCC systems,with practical implications for advancing miniaturized power source technologies.展开更多
In natural environment, tarnish was observed on the surface of historic and contemporary gold coins in several countries. Few years after the emergence of panda gold coins, several red spots were appeared on the surfa...In natural environment, tarnish was observed on the surface of historic and contemporary gold coins in several countries. Few years after the emergence of panda gold coins, several red spots were appeared on the surface. To identify the stains and to examine the spots, optical microscope （OM）, scanning electron microscope （SEM）, electron microprobe analysis （EMPA）, X-ray photoelectron spectroscopy （XPS）, and X-ray diffraction （XRD） were used. It was found by microscopic observation that the stain has a dark blue central area surrounded by a large area with a nuance of colors from brown to red. Red spots usually contain holes in the center, which are distributed along the forging stress zones formed in the struck process. From the surface analyses using EMPA, sulfur and silver are detected besides gold, and the contents of Ag and S at the tarnish part are higher than those at the other part. Furthermore, distributions of Ag and S are correlated with the morphology of stains. XPS shows that components of stains are Ag2S and Ag2SO4 and the former is much predominant. These results are confirmed using XRD analysis. Accelerated tarnish test of gold in an atmosphere containing sulfur compound proves that the similar phenomenon appears when a small amount of silver is present on the surface of gold. It can be concluded that the occurrence of tarnish stains is caused by the presence of Ag and S.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
基金Supported by the Project of Instrument Upgraded of Ministry of Science and Technology of China
文摘Twenty Yongzheng copper coins were fast dating by X-ray energy dispersive spectrometer with scanning electron microscope(SEM-EDS)according to official ingredient.The 20 coins were classified in two groups according to the results.Group 1 represents the coins minted before AD 1728 and group 2 represents the coins minted after AD 1728.At concentration range(0.00%–5.13%),the distribution of lead is not homogeneous in the coins,and the largest diameter of lead inclusion is less than 15μm.The official fineness degrade is supported.
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Non-destructive analysis of some electrum coins from post Gupta period and of coins from different mints of Mughal emperors, Shahjahan and Aurangzeb, have been done by instrumental neutron activation analysis (INAA) using 252Cf neutron source. The elemental content of these coins are determined by comparator method by measuring the activities of the radioisotopes formed after (n,r) reactions, at their corresponding photopeaks. It is found that identified electrum coins contain copper as a major component and hence can be termed as cupro-electrum coins. As regards the analysis of coins from different mints there is no much variation in silver content while copper content varies from mint to mint. Coins from both the emperors are found to contain considerable amount of gold.
文摘The radioactivity induced in the coins from Satvahanas,Ahmadshah Bahamani,Gujrat Sultan,Nizamshahi and Marathas after(n,γ) reactions for the elemeats of interest is measured on multichannel analyzer coupled to high purity germanium detector and percentage of these elements is determined by comparator method of NAA.All these coins are found to be copper based with the presence of As,Sb,In,An,Sn and Mn.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11104128,61205119 and 41206084the Natural Science Foundation of Jiangxi-Provincial Office of Education under Grant No GJJ13485the Doctor Start-up Foundation of Nanchang Hangkong University under Grant No EA201008229
文摘We numerically study the effect of the quantum coins on the two-particle quantum walks on an infinite line. Both non-interacting and interacting particles are considered. The joint probability as well as the bunching or anti- bunching behavior are greatly affected by the phase factors in the coin operation. Further, the spatial correlation can be maximized by choosing appropriate coin parameters. The entanglement between the two particles can be adjusted in the same manner.
基金Supported by the National Natural Science Foundation of China under Grant No 11175087the National Basic Research Program of China under Grant No 2009CB929501the Project on Graduate Students’Education and Innovation of Jiangsu Province under Grant No CXZZ13_0392
文摘The dynamical and static disordered quantum walks were extensively studied recently. It is found that, for the dynamicM disorder case, the transport behavior of particles is diffusive, and for the static disorder ease the transport behavior is localized. In this work, we study the effect of quantum coins on the transport behaviors of the binary disordered quantum walks. We lind that once the coins satisfy certain conditions, the sub-ballistic spreading could be found in binary dynamical disorder quantum walks, and the sub-ballistic, diffusive and sub- diffusive spreadings could be found in binary static disorder quantum walks. We obtain the necessary conditions for those abnormal diffusive behaviors.
文摘Non-fungible tokens(NFTs)are one-of-a-kind digital assets that are stored on a blockchain.Examples of NFTs include art(e.g.,image,video,animation),collectables(e.g.,autographs),and objects from games(e.g.,weapons and poisons).NFTs provide content creators and artists a way to promote and sell their unique digital material online.NFT coins underpin the ecosystems that support NFTs and are a new and emerging asset class and,as a new and emerging asset class,NFT coins are not immune to economic uncertainty.This research seeks to address the following questions.What is the time and frequency relationship between economic uncertainty and NFT coins?Is the relationship similar across different NFT coins?As an emerging asset,do NFT coins exhibit explosive behavior and if so,what role does economic uncertainty play in their formation?Using a new Twitter-based economic uncertainty index and a related equity market uncertainty index it is found that wavelet coherence between NFT coin prices(ENJ,MANA,THETA,XTZ)and economic uncertainty or market uncertainty is strongest during the periods January 2020 to July 2020 and January 2022 to July 2022.Periods of high significance are centered around the 64-day scale.During periods of high coherence,economic and market uncertainty exhibit an out of phase relationship with NFT coin prices.Network connectedness shows that the highest connectedness occurred during 2020 and 2022 which is consistent with the findings from wavelet analysis.Infectious disease outbreaks(COVID-19),NFT coin price volatility,and Twitter-based economic uncertainty determine bubbles in NFT coin prices.
文摘RECENT findings on the East African coast confirm what many people have suspected for years： Trade between the Chinese and Africans existed long before Europeans stepped foot on the shores of East Africa＇s West Indian Ocean Coast.
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.
基金the financial support from the National Natural Science Foundation of China,Grant Nos.52307249the Natural Science Foundation of Shanghai Province,Nos.23ZR1465900+2 种基金the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission,Nos.23CGA25the Fundamental Research Funds for the Central Universities at Tongji University,Nos.PA2022000668/22120220426the Nanchang Automotive Institute of Intelligence&New Energy of Tongji University,Nos.TPD-TC202211-02。
文摘The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systematic replacement of metallic structural support components(MSSCs)to minimize non-active constituent ratios,contingent upon maintaining robust interfacial contact integrity among electrodes,separators,and battery shells.Herein,we present a novel LPCC configuration employing solvent-free processed ultra-thick fluorinated carbon cathode(UCFxC)to achieve complete MSSCs elimination.The engineered UCFxC demonstrates exceptional areal capacity metrics(249.45 mg cm^(-2),215.77 m Ah cm^(-2)),enabling a 27.8% mass reduction compared with conventional laboratoryassembled coin cell while achieving 941.5% energy density enhancement through optimized electrode conductivity.Notably,single-walled carbon nanotube(SWCNT)-modified UCFxC architectures exhibited superior performance with energy exceeding 1.0 Wh at 50℃.This architectural paradigm provides valuable insights for developing next-generation high-energy-density LPCC systems,with practical implications for advancing miniaturized power source technologies.
文摘In natural environment, tarnish was observed on the surface of historic and contemporary gold coins in several countries. Few years after the emergence of panda gold coins, several red spots were appeared on the surface. To identify the stains and to examine the spots, optical microscope （OM）, scanning electron microscope （SEM）, electron microprobe analysis （EMPA）, X-ray photoelectron spectroscopy （XPS）, and X-ray diffraction （XRD） were used. It was found by microscopic observation that the stain has a dark blue central area surrounded by a large area with a nuance of colors from brown to red. Red spots usually contain holes in the center, which are distributed along the forging stress zones formed in the struck process. From the surface analyses using EMPA, sulfur and silver are detected besides gold, and the contents of Ag and S at the tarnish part are higher than those at the other part. Furthermore, distributions of Ag and S are correlated with the morphology of stains. XPS shows that components of stains are Ag2S and Ag2SO4 and the former is much predominant. These results are confirmed using XRD analysis. Accelerated tarnish test of gold in an atmosphere containing sulfur compound proves that the similar phenomenon appears when a small amount of silver is present on the surface of gold. It can be concluded that the occurrence of tarnish stains is caused by the presence of Ag and S.
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.
