Sunlight is the most abundant renewable energy resource,providing the earth with enough power that is capable of taking care of all of humanity’s desires-a hundred times over.However,as it is at times diffuse and int...Sunlight is the most abundant renewable energy resource,providing the earth with enough power that is capable of taking care of all of humanity’s desires-a hundred times over.However,as it is at times diffuse and intermittent,it raises issues concerning how best to reap this energy and store it for times when the Sun is not shining.With increasing population in the world and modern economic development,there will be an additional increase in energy demand.Devices that use daylight to separate water into individual chemical elements may well be the answer to this issue,as water splitting produces an ideal fuel.If such devices that generate fuel were to become widely adopted,they must be low in cost,both for supplying and operation.Therefore,it is essential to research for cheap technologies for water ripping.This review summarizes the progress made toward such development,the open challenges existing,and the approaches undertaken to generate carbon-free energy through water splitting.展开更多
Standard free energies (ΔG0t(i) ) and entropies (ΔS0t(i)) of transfer of some homologous α-amino acids viz. glycine (gly), dl-alanine (ala), dl-α-amino butyric acid (aba) and dl-nor-valine (nor-val) from protic et...Standard free energies (ΔG0t(i) ) and entropies (ΔS0t(i)) of transfer of some homologous α-amino acids viz. glycine (gly), dl-alanine (ala), dl-α-amino butyric acid (aba) and dl-nor-valine (nor-val) from protic ethylene glycol (EG) to dipolar aprotic N,N-dimethyl formamide (DMF) have been evaluated from solubility measure-ments at five equidistant temperatures i.e from 15 to 350C. The observed ΔG0t(i) and TΔS0t(i) Vs composition profiles are complicated because of the various interaction effects. The chemical effects of the transfer Gibbs energies (ΔG0t.ch(i)) and entropies of transfer (ΔS0t.ch(i)) have been obtained after elimination of cavity effect, estimated by the scaled particle theory and dipole-dipole interaction effects, estimated by the use of Keesom-orientation expression. The chemical contributions of transfer energetics of homologous α-amino acids are guided by the composite effects of increased dispersion interaction, basicity and decreased acidity, hydrogen bonding effects and solvophobic solvation of ethylene glycol and N, N-dimethyl formamide mixed solvent as compared to that of reference solvent (ethylene glycol).展开更多
文摘Sunlight is the most abundant renewable energy resource,providing the earth with enough power that is capable of taking care of all of humanity’s desires-a hundred times over.However,as it is at times diffuse and intermittent,it raises issues concerning how best to reap this energy and store it for times when the Sun is not shining.With increasing population in the world and modern economic development,there will be an additional increase in energy demand.Devices that use daylight to separate water into individual chemical elements may well be the answer to this issue,as water splitting produces an ideal fuel.If such devices that generate fuel were to become widely adopted,they must be low in cost,both for supplying and operation.Therefore,it is essential to research for cheap technologies for water ripping.This review summarizes the progress made toward such development,the open challenges existing,and the approaches undertaken to generate carbon-free energy through water splitting.
文摘Standard free energies (ΔG0t(i) ) and entropies (ΔS0t(i)) of transfer of some homologous α-amino acids viz. glycine (gly), dl-alanine (ala), dl-α-amino butyric acid (aba) and dl-nor-valine (nor-val) from protic ethylene glycol (EG) to dipolar aprotic N,N-dimethyl formamide (DMF) have been evaluated from solubility measure-ments at five equidistant temperatures i.e from 15 to 350C. The observed ΔG0t(i) and TΔS0t(i) Vs composition profiles are complicated because of the various interaction effects. The chemical effects of the transfer Gibbs energies (ΔG0t.ch(i)) and entropies of transfer (ΔS0t.ch(i)) have been obtained after elimination of cavity effect, estimated by the scaled particle theory and dipole-dipole interaction effects, estimated by the use of Keesom-orientation expression. The chemical contributions of transfer energetics of homologous α-amino acids are guided by the composite effects of increased dispersion interaction, basicity and decreased acidity, hydrogen bonding effects and solvophobic solvation of ethylene glycol and N, N-dimethyl formamide mixed solvent as compared to that of reference solvent (ethylene glycol).