船用固体氧化物燃料电池与二冲程低速双燃料发动机集成动力系统的设计与优化

A combined system including a solid oxide fuel cell(SOFC)and an internal combustion engine(ICE)is proposed in this paper.First,a 0-D model of SOFC and a 1-D model of ICE are built as agent models.Second,parameter analysis of the system is conducted based on SOFC and ICE models.Results show that the number of cells,current density,and fuel utilization can influence SOFC and ICE.Moreover,a deep neural network is applied as a data-driven model to conduct optimized calculations efficiently,as achieved by the particle swarm optimization algorithm in this paper.The results demonstrate that the optimal system efficiency of 51.8%can be achieved from a 22.4%/77.6%SOFC-ICE power split at 6000 kW power output.Furthermore,promising improvements in efficiency of 5.1%are achieved compared to the original engine.Finally,a simple economic analysis model,which shows that the payback period of the optimal system is 8.41 years,is proposed in this paper.

In situ identification of environmental microorganisms with Raman spectroscopy

Microorganisms in natural environments are crucial in maintaining the material and energy cycle and the ecological balance of the environment.However,it is challenging to delineate environmental microbes'actual metabolic pathways and intraspecific heterogeneity because most microorganisms cannot be cultivated.Raman spectroscopy is a culture-independent technique that can collect molecular vibration profiles from cells.It can reveal the physiological and biochemical information at the single-cell level rapidly and non-destructively in situ.The first part of this review introduces the principles,advantages,progress,and analytical methods of Raman spectroscopy applied in environmental microbiology.The second part summarizes the applications of Raman spectroscopy combined with stable isotope probing(SIP),fluorescence in situ hybridization(FISH),Raman-activated cell sorting and genomic sequencing,and machine learning in microbiological studies.Finally,this review discusses expectations of Raman spectroscopy and future advances to be made in identifying microorganisms,especially for uncultured microorganisms.

A new method of studying collapsibility of loess

A new triaxial testing system that could control suction in wetting-induced collapsible tests was success-fully developed to study the suction effects on wetting-induced collapsible deformation.The pedestal of the triaxial cell was made up of two parts,and the equipment not only could control suction but also could make water accessible to soil.A pressure/volume-controlled equip-ment was combined with the triaxial system to measure the water volume absorbed by samples accurately and to add pressure on water to filtrate into the sample.The apparatus could measure volume change precisely and keep the deviator stress unvaried,as well as measure the volume of water filtrating into the samples exactly.A triaxial collapsible testing procedure was described using the new apparatus for undisturbed collapsible loess with controlled suction.Furthermore,a series of double triaxial collapsible tests were conducted under different suctions and the same net cell pressure,and tests under different net cell pressures and the same suction were also done.It was indicated that the collapsible deformation increased with the increasing suction,and the effect of the net cell pressure on collapsible deformation was remarkable.The new triaxial apparatus was a useful facility to study the collapsible behavior of loess.