The age at which a woman enters natural menopause has also been associated to death from any cause.Menopause is a natural component of aging that happens between the ages of 45 and 55,with the average menopausal age b...The age at which a woman enters natural menopause has also been associated to death from any cause.Menopause is a natural component of aging that happens between the ages of 45 and 55,with the average menopausal age being 51.Previous research has revealed the age at which women reach menopause,but there is no evidence to support the link between menopause and longevity.We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article.In this paper,we aim to predict the maximum lifespan of women at mean menopausal age.展开更多
The structural, electronic and mechanical properties of transition metal hydrides （TMH, TM=Mo, Tc, Ru） are investigated by means of first principles calculation based on density fimctional theory with generalized gr...The structural, electronic and mechanical properties of transition metal hydrides （TMH, TM=Mo, Tc, Ru） are investigated by means of first principles calculation based on density fimctional theory with generalized gradient approximation. Among the five crystallographic structures that have been investigated, the cubic phase is found to be more stable than the hexagonal ones. A structural phase transition from ZB to WC in Moll, NaC1 to NiAs in TcH and NaCI to ZB to NiAs in RuH is also predicted under high pressure. The calculated elastic constants indicate that all the three hydrides are mechanically stable at ambient pressure.展开更多
The structural, electronic, elastic and magnetic properties of cerium, praseodymium and their hydrides REH x（RE=Ce, Pr and x=2, 3） were investigated by the first principles calculations based on density functional t...The structural, electronic, elastic and magnetic properties of cerium, praseodymium and their hydrides REH x（RE=Ce, Pr and x=2, 3） were investigated by the first principles calculations based on density functional theory using the Vienna ab-initio simulation package. At zero pressure all the hydrides were stable in the ferromagnetic state. The calculated lattice parameters were in good agreement with the experimental results. The bulk modulus decreased with the increase in the hydrogen content for these hydrides. The electronic structure revealed that di-hydrides were metallic whereas trihydrides were half metallic at zero pressure. A pressure-induced structural phase transition from cubic to hexagonal phase was predicted in these hydrides. The computed elastic constants indicated that these hydrides were mechanically stable at zero pressure. The calculated Debye temperature values were in good agreement with experimental and other theoretical results. A half metallic to metallic transition was also observed in REH3 under high pressure. Ferromagnetism was quenched in these hydrides at high pressures.展开更多
Ab initio calculations are performed to investigate the ground state properties, structural phase transition, electronic structure and mechanical properties of lithium nitride （Li3N）, lithium imide （Li2NH） and lit...Ab initio calculations are performed to investigate the ground state properties, structural phase transition, electronic structure and mechanical properties of lithium nitride （Li3N）, lithium imide （Li2NH） and lithium amide （LiNH2）. The computed ground state properties like equilibrium lattice constant, cell volume, valence electron density, cohesive energy, bulk modulus and its derivatives are in good agreement with available experimental data. The structural phase transitions from α-P6/mmm to β-P63/mmc phase at a pressure of 17.5 GPa in LiaN and cubic （Fm3m） to hexagonal （P63/ mmc） phase at a pressure of 102 GPa in lithium imide （Li2NH） are observed. A new high pressure hexagonal （P63/mmc） phase is predicted for LiENH. Electronic structure reveals that Li3N and LiNH2 are semiconductors, whereas Li2NH is an insulator. The calculated elastic constants indicate that these materials are mechanically stable at ambient condition.展开更多
It is true and sooth as far as Abraham Linkan’s definition of democracy being implausible in a vast global democratic system. The definition of democracy of Abraham linkan is certainly palatable and practically reali...It is true and sooth as far as Abraham Linkan’s definition of democracy being implausible in a vast global democratic system. The definition of democracy of Abraham linkan is certainly palatable and practically realizable in those ancient times for states, then existed were smaller and nanoscopic and people could directly participate and realize the collective decisions (Abraham Linkan defamation―of the people, by the people, and for the people). In modern democracies, the Abraham Linkan’s defamation was fast losing its relevance and people were groping in the dark. The citizens were challenging in the system on its essentials/prerequisites the state in modern times not only shirking its responsibility but also getting insulated. It was/is at this juncture the dawn of ICT on the horizon made people redeem nuances of participatory democracy development rhythm of true democratic ideals ICT’s initiation in good governance heralded a new phase of participatory democracy development attended to the glorious of direct democracy. The emergency of the ICT filled the vacuum existed between govt. and citizens. It also narrowed down the gap between citizens and govt by holding out their responsibility in terms of development governance in veritably transparent manner. ICT, in other words, the net-work of information, are accessible to all decision-makers and also felicitated in decision-makers to have a direct access to the existing situation and there by strengthening the decision-making process. ICT by its inner strength restored the democratic strength to the citizenry. Thus, the main properties of ICT, such as transfrancy, participation, rule of low, efficiency and effectiveness, etc. propped up the governing entity get entrenched in good governance. Also, it opened new visas for creative discourse based on ICT’s utility in the field of planning and designing of strategies of development at all levels of governing pyramid. The ICT’s fold opportunities for both ruling and being ruled such that a citizenry could collectively constituency observe the action of ruling class as it is entailed to and in turn the government, in principal, has responsibility to focus on and positively respond to. Hence, ICT as a potential agency bridges the gap in all aspect of system yielding place for communion development. The role, ICT in a wider-democratic system and good governance, was also discussed. Conclusion is also drawn keeping in riew its futuristic perspectives and prospects.展开更多
Ab initio calculations are performed to investigate the structural stability, electronic structure and mechanical properties of rubidium metal hydrides RbMH4（M = B, Al, Ga） for five different crystal structures, nam...Ab initio calculations are performed to investigate the structural stability, electronic structure and mechanical properties of rubidium metal hydrides RbMH4（M = B, Al, Ga） for five different crystal structures, namely hexagonal（P63mc）, tetragonal（P42/nmc）, tetragonal（P421c）, orthorhombic（Pnma） and monoclinic（P21/c）. Among the considered structures, tetragonal（P421c） phase is found to be the most stable one for these metal hydrides at normal pressure. A pressure-induced structural phase transition from tetragonal（P421c） to monoclinic（P21/c） phase is observed in all the three metal hydrides. The electronic structure reveals that these hydrides are wide band gap semiconductors. The calculated elastic constants indicate that these alkali metal tetrahydrides are mechanically stable at normal pressure.展开更多
文摘The age at which a woman enters natural menopause has also been associated to death from any cause.Menopause is a natural component of aging that happens between the ages of 45 and 55,with the average menopausal age being 51.Previous research has revealed the age at which women reach menopause,but there is no evidence to support the link between menopause and longevity.We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article.In this paper,we aim to predict the maximum lifespan of women at mean menopausal age.
文摘The structural, electronic and mechanical properties of transition metal hydrides （TMH, TM=Mo, Tc, Ru） are investigated by means of first principles calculation based on density fimctional theory with generalized gradient approximation. Among the five crystallographic structures that have been investigated, the cubic phase is found to be more stable than the hexagonal ones. A structural phase transition from ZB to WC in Moll, NaC1 to NiAs in TcH and NaCI to ZB to NiAs in RuH is also predicted under high pressure. The calculated elastic constants indicate that all the three hydrides are mechanically stable at ambient pressure.
文摘The structural, electronic, elastic and magnetic properties of cerium, praseodymium and their hydrides REH x（RE=Ce, Pr and x=2, 3） were investigated by the first principles calculations based on density functional theory using the Vienna ab-initio simulation package. At zero pressure all the hydrides were stable in the ferromagnetic state. The calculated lattice parameters were in good agreement with the experimental results. The bulk modulus decreased with the increase in the hydrogen content for these hydrides. The electronic structure revealed that di-hydrides were metallic whereas trihydrides were half metallic at zero pressure. A pressure-induced structural phase transition from cubic to hexagonal phase was predicted in these hydrides. The computed elastic constants indicated that these hydrides were mechanically stable at zero pressure. The calculated Debye temperature values were in good agreement with experimental and other theoretical results. A half metallic to metallic transition was also observed in REH3 under high pressure. Ferromagnetism was quenched in these hydrides at high pressures.
基金The financial assistance from UGC under research award scheme(No.F:30-36/2011 SA-II)
文摘Ab initio calculations are performed to investigate the ground state properties, structural phase transition, electronic structure and mechanical properties of lithium nitride （Li3N）, lithium imide （Li2NH） and lithium amide （LiNH2）. The computed ground state properties like equilibrium lattice constant, cell volume, valence electron density, cohesive energy, bulk modulus and its derivatives are in good agreement with available experimental data. The structural phase transitions from α-P6/mmm to β-P63/mmc phase at a pressure of 17.5 GPa in LiaN and cubic （Fm3m） to hexagonal （P63/ mmc） phase at a pressure of 102 GPa in lithium imide （Li2NH） are observed. A new high pressure hexagonal （P63/mmc） phase is predicted for LiENH. Electronic structure reveals that Li3N and LiNH2 are semiconductors, whereas Li2NH is an insulator. The calculated elastic constants indicate that these materials are mechanically stable at ambient condition.
文摘It is true and sooth as far as Abraham Linkan’s definition of democracy being implausible in a vast global democratic system. The definition of democracy of Abraham linkan is certainly palatable and practically realizable in those ancient times for states, then existed were smaller and nanoscopic and people could directly participate and realize the collective decisions (Abraham Linkan defamation―of the people, by the people, and for the people). In modern democracies, the Abraham Linkan’s defamation was fast losing its relevance and people were groping in the dark. The citizens were challenging in the system on its essentials/prerequisites the state in modern times not only shirking its responsibility but also getting insulated. It was/is at this juncture the dawn of ICT on the horizon made people redeem nuances of participatory democracy development rhythm of true democratic ideals ICT’s initiation in good governance heralded a new phase of participatory democracy development attended to the glorious of direct democracy. The emergency of the ICT filled the vacuum existed between govt. and citizens. It also narrowed down the gap between citizens and govt by holding out their responsibility in terms of development governance in veritably transparent manner. ICT, in other words, the net-work of information, are accessible to all decision-makers and also felicitated in decision-makers to have a direct access to the existing situation and there by strengthening the decision-making process. ICT by its inner strength restored the democratic strength to the citizenry. Thus, the main properties of ICT, such as transfrancy, participation, rule of low, efficiency and effectiveness, etc. propped up the governing entity get entrenched in good governance. Also, it opened new visas for creative discourse based on ICT’s utility in the field of planning and designing of strategies of development at all levels of governing pyramid. The ICT’s fold opportunities for both ruling and being ruled such that a citizenry could collectively constituency observe the action of ruling class as it is entailed to and in turn the government, in principal, has responsibility to focus on and positively respond to. Hence, ICT as a potential agency bridges the gap in all aspect of system yielding place for communion development. The role, ICT in a wider-democratic system and good governance, was also discussed. Conclusion is also drawn keeping in riew its futuristic perspectives and prospects.
文摘Ab initio calculations are performed to investigate the structural stability, electronic structure and mechanical properties of rubidium metal hydrides RbMH4（M = B, Al, Ga） for five different crystal structures, namely hexagonal（P63mc）, tetragonal（P42/nmc）, tetragonal（P421c）, orthorhombic（Pnma） and monoclinic（P21/c）. Among the considered structures, tetragonal（P421c） phase is found to be the most stable one for these metal hydrides at normal pressure. A pressure-induced structural phase transition from tetragonal（P421c） to monoclinic（P21/c） phase is observed in all the three metal hydrides. The electronic structure reveals that these hydrides are wide band gap semiconductors. The calculated elastic constants indicate that these alkali metal tetrahydrides are mechanically stable at normal pressure.
