英语翻译Hydrogen is an idea,l clean and sustainable energy sourc

英语翻译
Hydrogen is an idea,l clean and sustainable energy source for the future because of its high conversion and nonpolluting nature.Biohydrogen production by dark-fermentation appears to have a great potential to be developed for practical application.However,one limiting factor affecting the development of hydrogen-production industrialization is that the hydrogen-producing capacity of bacteria is lower,so how to increase bacteria’s hydrogen-producing abilitywill be an urgent issue.In this experiment,2 mutants,namelyUV3 andUV7,were obtained by ultra-violet radiation.They grew and produced hydrogen efficiently on iron-containing medium.The hydrogen evolution of UV3 and UV7 were 2 356·68 ml/L and 2 219·62 ml/L at a glucose concentration of 10 g/L,respectively.With wild parent strain Ethanoligenens sp.ZGX4,the hydrogen evolution was 1 806·02 ml/L under the same conditions.Mutants’hydrogen-producing capacities were about 29·71% and 22·22% higher than that of wild parent strain ZGX4.The maximum H2 production rate by mutants UV3 and UV7 were estimated to be 32·57 mmolH2/g cell h and 31·19 mmolH2/g cell h,respectively,which were 38·18% and 34·78% higher than the control (23·57 mmolH2/g cellh).The abundant products of UV3 and UV7 were ethanol and acetic,which accounted for 95% -98% of total soluble microbial products.In each case,mutant strains UV3 and UV7 evolved hydrogen at a higher rate than the wild type,showing a possible potential for commercial hydrogen production.Another mutant named UV20’ was also gained whose main end metabo lites were butyric acid and acetic acid.This would provide researched material for a discussion of metabolic pathways of hydrogen-producing bacteria.