Nonlinearity acoustic parameter B/A in organic liquids

Based on Jacobson's free length theory and the dependence of ultrasonic velocity on the free length in organic liquids, the equation of nonlinearity acoustic parameter B/A was given, and the calculated nonlinearity acoustic parameter B/A in some organic liquids are in good agreement with the measured results.

Dependence of the coefficient of ultrasonic velocity on the coefficient of free length in organic liquids

On the basis of Jacobson's free length theory and the theory of pressure coefficient and temperature coefficient of free length in liquids, the relationship between the pressure coefficient of ultrasonic velocity and the pressure coefficient of free length, and the relationship between the temperature coefficient of ultrasonic velocity and the temperature coefficient of free length were studied. Relevant equations were given, and the pressure coefficient and temperature coefficient of ultrasonic velocity were calculated, which are in agreement with the measured values.

Liquid organic hydrogen carriers

The development of efficient hydrogen storage materials is one of the biggest technical challenges for the coming ＂hydrogen economy＂. The liquid organic hydrogen carriers （LOHCs） with high hydrogen contents, reversibilities and moderate dehydrogenation kinetics have been considered as an alternative option supplementing the extensively investigated inorganic hydride systems. In this review, LOHCs for long distance H2 transport and for onboard application will be discussed with the focuses of the design and development of LOHCs and their hydrogenation ＆ dehydrogenation catalyses.

Ultrasonic study on organic liquid and binary organic liquid mixtures by using Schaaffs＇ collision factor theory

Based on Schaaff＇s collision factor theory （CFT） in liquids, the equations for nonlinear ultrasonic parameters in both organic liquid and binary organic liquid mixtures are deduced. The nonlinear ultrasonic parameters, including pressure coefficient, temperature coefficients of ultrasonic velocity, and nonlinear acoustic parameter B/A in both organic liquid and binary organic liquid mixtures, are evaluated for comparison with the measured results and data from other sources. The equations show that the coefficient of ultrasonic velocity and nonlinear acoustic parameter B/A are closely related to molecular interactions. These nonlinear ultrasonic parameters reflect some information of internal structure and outside status of the medium or mixtures. From the exponent of repulsive forces of the molecules, several thermodynamic parameters, pressure and temperature of the medium, the nonlinear ultrasonic parameters and ultrasonic nature of the medium can be evaluated. When evaluating and studying nonlinear acoustic parameter B/A of binary organic liquid mixtures, there is no need to know the nonlinear acoustic parameter B/A of the components. Obviously, the equation reveals the connection between the nonlinear ultrasonic nature and internal structure and outside status of the mixtures more directly and distinctly than traditional mixture law for B/A, e.g. Apfel＇s and Sehgal＇s laws for liquid binary mixtures.

Bimetallic Ru-Ni/TiO2 catalysts for hydrogenation of N-ethylcarbazole:Role of TiO2 crystal structure

Hydrogenation of N-ethylcarbazole(NEC),the hydrogen lean form of a liquid organic hydrogen carrier,on TiO2 supported Ru-Ni bimetallic catalysts is investigated.Crystal structure of TiO2 plays a critical role on the hydrogenation activity and selectivity towards fully hydrogenated product.Ru/anatase catalyst exhibits higher selectivity but lower reactivity compared to Ru/rutile catalyst.Ni addition significantly promotes the performance of Ru/anatase catalyst while causes severe performance deterioration of Ru/rutile catalyst.Commercial P25,a mixture of anatase and rutile phases in approximate ratio A/R1/4,is found to be the best TiO2 support for NEC hydrogenation.Ru/P25 catalyst outperforms both Ru/rutile and Ru/anatase and its activity can be further slightly improved by Ni addition.The unexpected synergism between the two different TiO2 phases for Ru based NEC hydrogenation catalysts is related to metal-support interaction and Ru-Ni interaction.

Hydrogen storage by liquid organic hydrogen carriers:Catalyst,renewable carrier,and technology--A review

Hydrogen has attracted widespread attention as a carbon-neutral energy source,but developing efficient and safe hydrogen storage technologies remains a huge challenge.Recently,liquid organic hydrogen carriers(LOHCs)technology has shown great potential for efficient and stable hydrogen storage and transport.This technology allows for safe and economical large-scale transoceanic transportation and long-cycle hydrogen storage.In particular,traditional organic hydrogen storage liquids are derived from nonrenewable fossil fuels through costly refining procedures,resulting in unavoidable environmental contamination.Biomass holds great promise for the preparation of LOHCs due to its unique carbon-balance properties and feasibility to manufacture aromatic and nitrogen-doped compounds.According to recent studies,almost 100%conversion and 92% yield of benzene could be obtained through advanced biomass conversion technologies,showing great potential in preparing biomass-based LOHCs.Overall,the present LOHCs systems and their unique applications are introduced in this review,and the technical paths are summarized.Furthermore,this paper provides an outlook on the future development of LOHCs technology,focusing on biomass-derived aromatic and N-doped compounds and their applications in hydrogen storage.

Study on gamma response function of EJ301 organic liquid scintillator with GEANT4 and FLUKA

The gamma response function is required for energy calibration of EJ301 （5 cm in diameter and 20 cm in height） organic liquid scintillator detector by means of gamma sources. The GEANT4 and FLUKA Monte Carlo simulation packages were used to simulate the response function of the detector for standard 22Na, 60Co, 137Cs gamma sources. The simulated results showed a good agreement with experimental data by incorporating the energy resolution function to simulation codes. The energy resolution and the position of the maximum Compton electron energy were obtained by comparing measured light output distribution with simulated one. The energy resolution of the detector varied from 21.2% to 12.4% for electrons in the energy region from 0.341 MeV to 1.12 MeV. The accurate position of the maximum Compton electron energy was determined at the position 81% of maximum height of Compton edges distribution. In addition, the relation of the electron energy calibration and the effective neutron detection thresholds were described in detail. The present results indicated that both packages were suited for studying the gamma response function of EJ301 detector.

Nonstoichiometric Yttrium Hydride–Promoted Reversible Hydrogen Storage in a Liquid Organic Hydrogen Carrier

N-Ethylcarbazole(NEC)is one of the most promising liquid organic hydrogen carriers(LOHCs),but its application is limited by sluggish kinetics due to lack of high-efficiency,low-cost catalysts.This work reports a cobalt(Co)-based catalyst promoted by nonstoichiometric yttrium hydride(YH_(3−x))to achieve high-efficiency,reversible hydrogen storage in NEC,with>5.5 wt%reversible hydrogen storage capacity could be achieved below 473 K,and with good kinetics.The YH_(3−x)-promoted Co-based catalyst is the first non-noble metal catalyst with high activity for NEC hydrogenation and 12H-NEC dehydrogenation reactions.A mechanistic study suggests that YH_(3−x)facilitates the reversible hydrogen transfer both in the hydrogenation and the dehydrogenation reactions.The nonstoichiometric YH_(3−x)contained both lattice H and H vacancies with tunable H chemical potential serve as the H donor and H acceptor for reversible hydrogen transfer.Our results support the practical application of LOHCs and inspire new approaches for the utilization of conventional metal hydrides to promote versatile H transfer reactions.

Highly efficient hydrogen production from methanol by single nickel atoms anchored on defective boron nitride nanosheet

Exploiting inexpensive and effective nickel-based catalysts that produce hydrogen from liquid organic hydrogen carriers(LOHCs)is crucial to alleviating the global energy and environmental crisis.In this study,we report a rational strategy that can realize atomically dispersed Ni atoms anchored on vacancy-abundant boron nitride nanosheets(Ni1/h-BNNS)with high specific surface area(up to 622 m^(2)·g^(-1))and abundant hydroxyl groups for high efficient hydrogen production.Methanol dehydrogenation results show an excellent hydrogen production performance catalyzed by this Ni1/h-BNNS,as evidenced by a remarkably high H_(2) yield rate(1684.23 mol·mol_(Ni)^(-1)·h^(-1)),nearly 100%selectivity toward hydrogen and CO,and high anti-coking performance.Density functional theory(DFT)calculations reveal that the outstanding catalytic performance of Ni1/h-BNNS primarily originates from the unique coordinated environment of atomically dispersed Ni(Ni-B_(2)O_(2))and the synergistic interaction between Ni single atoms and the h-BNNS support.Specifically,the coordinated O atoms play a decisive role in promoting the activity of Ni,and the neighboring B sites significantly decrease the energy barriers for the adsorption of key intermediates of methanol dehydrogenation.This study offers a novel strategy for developing high-performance and stable single-atom Ni catalysts by precisely controlling single-atom sites on h-BN support for sustainable hydrogen production.

Progress in electrolytes for beyond-lithium-ion batteries

The constant increase in global energy demand and stricter environmental standards are calling for advanced energy storage technologies that can store electricity from intermittent renewable sources such as wind,solar,and tidal power,to allow the broader implementation of the renewables.The gridoriented sodium-ion batteries,potassium ion batteries and multivalent ion batteries are cheaper and more sustainable alternatives to Li-ion,although they are still in the early stages of development.Additional optimisation of these battery systems is required,to improve the energy and power density,and to solve the safety issues caused by dendrites growth in anodes.Electrolyte,one of the most critical components in these batteries,could significantly influence the electrochemical performances and operations of batteries.In this review,the definitions and influences of three critical components(salts,solvents,and additives)in electrolytes are discussed.The significant advantages,challenges,recent progress and future optimisation directions of various electrolytes for monovalent and multivalent ions batteries(i.e.organic,ionic liquid and aqueous liquid electrolytes,polymer and inorganic solid electrolytes)are summarised to guide the practical application for grid-oriented batteries.

A new technique helps to uncover unknown peptides and disinfection by-products in water

Environmental water samples can be extremely complex,with potentially thousands of molecules that can derive from natural organic matter（NOM）and thousands that derive from anthropogenic contaminants.As complex as these samples are,drinking water can be even more complex.Due to disinfectants that are used to treat drinking water（e.g.,chlorine,chloramines,

Effects of zero burning waste on the quality of liquid fertilizer and vermicompost

Peatland is an important ecosystem in Indonesia.But in almost every dry season,drained peatlands have been subject to detrimental wildfires.As a response,the government has explicitly prohibited the burning of land since 2016.To clear the land of crop residues and conduct zero burning practices,one alternative method is to utilize the waste biomass to support the cultivation of earthworms(vermiculture).This study examined the quality of liquid fertilizers and compost produced from vermiculture using a completely randomized factorial design,consisting of two treatment factors.The first factor was worm type,with two species used in this research named Lumbricus rubellus and Eudrilus eugeniae.The second factor was the type of feed provided to the worms,comprising no feed(control),vegetable waste,and crop residue waste resulting from zero burning land preparation.The type of feed significantly affected the pH value of the liquid fertilizer produced by the vermiculture but did not significantly affect the nutrient contents(N,P,and K).The combination of the types of earthworms and types of feed significantly affected the pH value of the vermicompost.The combination of worm types and feed types had a significant effect on exchangeable Ca,but not on exchangeable Mg,Na,and K.In combination,green vegetable waste and Lumbricus rubellus produced the greatest effect on soil CEC.However,for Base Saturation,the control(no food)and Eudrilus eugeniae showed the highest value.Types of worms and types of feed had a significant effect on the exchangeable Mg,while the other three parameters made no significant differences.Zero burning waste and Eudrilus eugeniae provide a better exchangeable Ca and Mg.In contrast,no-feeding and Eudrilus eugeniae have a better effect on exchangeable Na and K.Types of worms and types of feed did not significantly affect the weight of worm colonies,but the addition of feed increased the weight of worms with the highest weight resulting from the use of zero burning waste feed.The results showed that crop residue wastes were potentially good as a feed for earthworms.