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Absorption chiller represents a technology that facilitates the recuperation of low-grade thermal energy. However, commonly used working fluids, such as water/lithium bromide (LiBr) and ammonia/water, exhibit several drawbacks, including issues related to corrosion, crystallization, toxicity, and explosiveness in the case of ammonia. Water/ionic liquids (ILs) are considered promising alternative working fluids due to their high efficiency. In this study, we initially employed the COSMO-SAC model to screen potential IL-water working pairs, considering numerous ILs, which encompassed 35 different anions and 18 cations. Three ILs with promising water absorption capacities were identified: 1-butyl-3-methylimidazole chloride ([Bmim][Cl]), 1-butyl-3-methylimidazole thiocyanate ([Bmim][SCN]), and 1-hexyl-3-methylimidazole chloride ([Hmim][Cl]). Subsequently, we measured the vapor–liquid equilibrium (VLE) data of water + [Bmim][Cl], + [Bmim][SCN], and + [Hmim][Cl] mixtures over a temperature range of 313.15 to 363.15 K, with IL mole fractions ranging from 0.15 to 0.50. The binary interaction parameters of the NRTL and e-NRTL models were fitted to the new data. Finally, we evaluated the coefficients of performance (COP) of the investigated working pairs in an absorption cycle. The predicted COPfor the water + [Hmim][Cl] pair is found to be slightly better than that of the water + LiBr pair.

In this study, hetero-two-dimensional correlation spectroscopy (hetero-2DCOS) combined with parallel factor analysis (PARAFAC) was employed to reveal the inner changes in the dissolved organic matter (DOM) components derived from soil amended with seven different composts. The dynamics of the four DOM components showed that the fluorescence peaks in each component varied in different directions during mineralization. Structural equation models (SEMs) demonstrated that the compost amendments changed the correlations of the total organic carbon (TOC), total nitrogen (TN), and bacterial community composition with DOM components and strengthened the cooperative function related to transformation of DOM components. The compost sources were further ranked as cabbage waste (CW) > chicken manure (CM), dairy cattle manure (DCM), tomato stem waste (TSW), peat (P) > municipal solid waste (MSW), sewage sludge (SS) by projection pursuit regression (PPR) analysis. It is helpful to improve the bioavailability of compost products to obtain composts with a particular function.

Humin (HM) is a complex mixture of molecules produced in the different biological processes, and the structural evolution of HM in the agricultural wastes composting are not well-known. Elucidating and comparing the structural evolution during livestock manure (LMC) and straw wastes (SWC) composting can help one to better understand the fates, features, and environmental impacts of HM. This study exploits excitation emission matrix-parallel factor (EEM-PARAFAC), two-dimensional correlation spectroscopy (2D-CoS), hetero-2DCoS, and structural equation model (SEM) to compare the fate of the HM. We fit a three-component EEM-PARAFAC model to characterize HM extracted from LMC and SWC. The results show that the HM evolution has a significant difference between LMC and SWC. As a result, the opposite change tendency and different change order of HM fluorescent components determine the different synthesis formation and evolution mechanisms. The diverse organic matter composition and dominant microbes might be the reason for the different evolution mechanism. Based on these results, a comprehensive view of the component changes of HM in the composting process is obtained. Furthermore, the superior potential of such an integrated approach during investigating the complex evolution in the environment was also demonstrated.

In the work, laboratory experiments were designed to simulate the collisional plasma environment of the ionosphere. Neutral gas was injected to increase the ion‐neutral collisions, and the ambient plasma subsequently transforms from the magnetospheric‐like collisionless plasma to the ionospheric‐like collisional one. In the collisionless plasma, the classical electrostatic Kelvin‐Helmholtz instability (KHI) was generated using an interpenetrating plasma method. However, the collisionless KHI was dissipated in the collisional plasma and subsequently a new wave mode was excited. The mode was identified as the collisional KHI by comparing the experimental results with the theoretical wave dispersion relation. The result indicates that the KHI can be excited in the ionospheric‐like collisional plasma, which could be applied to understand the generation mechanism of the ionospheric irregularities by the bottomside sheared flow. Ionospheric irregularities, in the form of density spikes and cavities, are universal in the ionosphere from low to high latitudes. The ionospheric irregularities have a significant impact on satellite radio communications. The Kelvin‐Helmholtz instability (KHI) was considered to play a significant role in the generation of the ionospheric irregularities. However, a key issue is that the generation of KHI in a collisional plasma has not been experimentally verified. In the work, laboratory experiments were conducted to simulate the collisional environment of the ionosphere. The result suggests that the shear‐driven KHIs can be generated in an ionospheric‐like collisional plasma. Through our experimental work, the theoretical mechanism can be more confidently applied to explain the excitation of ionospheric irregularities. Controlled laboratory experiments were designed to simulate the collisional plasma environment of the ionosphereIt was verified that the Kelvin‐Helmholtz instability can be generated in the modeling ionospheric plasmaThis work can be applied to understand the generation mechanism of the plasma irregularities with bottomside sheared flow

Laboratory observations of spontaneous emission of Alfvénic branch oscillations generated by a strong inhomogeneous plasma flow are reported in this work. Electrostatic KH instabilities in the subcyclotron frequency range were excited using the interpenetrating plasma method. Experiments indicate that spontanegeous Alfvénic branch oscillations occur when the plasma inhomogeneity increases above a threshold. The electromagnetic wave amplitude spreads out radially over a much larger extent than the electrostatic mode. Theoretical calculations using the MHD method also support the experimental observation. The result has important application in understanding the cross‐scale transport of particles and energies in astrophysical, space, and laboratory plasmas. Spontaneous emission of Alfvénic branch oscillations was observed in the laboratory plasmaThe electromagnetic emission was excited by strong localized inhomogeneous plasma flow, which is ubiquitous in space plasmaThis result can be applied to explain the cross‐scale plasma transport from solar wind to the magnetopause

Transversely accelerated ions and the associated heating of the high‐latitude ionosphere have been attributed to broadband extremely low frequency (BBELF) turbulence. Controlled laboratory tests of the hypotheses on the formation mechanism of BBELF waves have involved only a few examples, e.g., current‐driven and shear‐driven instabilities. In this work, electrostatic fluctuations in the ion cyclotron frequency range have been excited by inhomogeneous energy‐density‐driven instability (IEDDI). This was achieved using the interpenetrating plasma method with a much larger electric field scale size LEcomparable to the ion gyroradius ρi, which was challenging earlier because of plasma conditions. The peak frequency of the IEDDI spectrum falls as low as ω≈0.3ωci, where ωciis ion cyclotron frequency. This is an interesting result because the previous attempts could not produce such low‐frequency IEDDI, although it was known theoretically to be possible. The observations made by FAST, Freja, and Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites might be explainable in terms of the reported experimental results. The broadband ELF waves with peak frequency as low as ω≈0.3ωcihave been excited in laboratoryThe free energy source of electron density gradient and sheared E× Bflow were artificially controlledThe BBELF wave observed in the aurarol plasma could be explainable in terms of our results.

Laboratory experiments have been conducted to simulate the boundary processes of ionospheric depletion. The ionospheric depletion was modeled through releasing depletion chemical (SF6) into the ambient plasmas. These plasmas were segregated into two regions by a boundary layer of width electric scale length. In the localized boundary layer, the electron density decreased sharply that yielded steep density gradients. Meanwhile, the floating potential increased in the time scales of the lower hybrid (LH) period, which produced strong sheared electron flows. The shear frequency ωs=VE/LE, which characterizes the sheared flow, is much larger than the LH frequency ωLH. A coherent structure was observed when the floating potential fluctuations were analyzed using digital spectral analysis techniques. Comparison with the theory indicated that the structure is driven by the electron‐ion hybrid instability which is generated owing to the nonlinear coupling between the electron density gradient and the sheared electron flow. Our results are important to study the early phase nonlinear evolution of the ionospheric depletion, especially in the development of plasma irregularities and turbulence in the boundary layer. The ionospheric depletion was simulated in a laboratoryA vortex‐like coherent structure was observedThe structure is driven by electron‐ion hybrid instability