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Hydrogen energy draws increasing concerns as a kind of renewable and clean energy. Liquid metal (LM) activated Al–H 2 O reaction is recently emerging as an alternative for real-time hydrogen production. In this study, the energy consumption and environmental impact of this newly emerging method are evaluated via the life cycle assessment (LCA), which indicates that the utilization of waste Al could significantly relieve the energy and environmental issues. In addition, conceptual experiments were conducted to verify the feasibility of hydrogen generation from waste Al, and to disclose the hydrogen generation performances of Al samples in different forms. To balance the cost of LM and reaction efficiency, the optimum mass ratio of LM to Al were explored, and the reusability of LM was demonstrated. Further, a SWOT analysis is adopted to interpret the Strengths and Weakness of such hydrogen production method, and to evaluate the Opportunities and Threats it confronts. Overall, waste Al could provide an energy-saving and environmentally friendly approach to produce hydrogen, which is expected to exploit a new way towards the green hydrogen era. • Feasibility of instant hydrogen generation from waste Al is verified. • Costs of hydrogen generation from various Al sources are compared via LCA. • Energy cost of the method is about one ninth that of water electrolysis. • Performance and recyclability of LM activated Al–H 2 O reaction are evaluated. • SWOT analysis was conducted to guide further orientation of current strategy. [ABSTRACT FROM AUTHOR]

Highlights • A practical galinstan based minichannel cooling system was developed, which can dissipate heat 300 W/cm2 and 1500 W. • The thermal performance and hydrodynamic characteristic of galinstan based minichannel heat sink was evaluated. • The heat capacity thermal resistance was an important factor for galinstan based minichannel cooling. • The pressure losses of galinstan minichannel heat sink was far lower than the water microchannel heat sink. • This cooling system can operate silently, steadily and smoothly. Abstract This paper is dedicated to experimentally investigate the liquid galinstan based minichannel cooling for high heat flux and large heat power thermal management. Firstly, a compact electromagnetic pump towards effectively driving liquid metals was developed, which can provide high pressure head up to 100 kPa. Then, the minichannel heat sink was designed and manufactured, with width of channel 1 mm, height of channel 5 mm. Furthermore, the galinstan based minichannel cooling system was established and experimentally tested under different heating loads and pumping powers. The results show that galinstan based minichannel cooling system can dissipate heat with heat flux 300 W/cm2 and heat power 1500 W. And the thermal performance and hydrodynamic characteristic of minichannel heat sink using galinstan as coolant were obtained. It indicates that compared to water based minichannel cooling, galinstan based minichannel cooling can obtain a rather larger heat transfer enhancement, and the pressure losses of galistan based minichannel heat sink is much lower than that of water based microchannel cooling. Moreover, it is also found that heat capacity thermal resistance becomes a rather important factor for the thermal performance of galinstan based minichannel, due to the high thermal conductivity and lower heat capacity of galinstan. Furthermore, the galinstan based minichannel cooling system can operate silently, steadily and smoothly by using electromagnetic pump, which has no moving parts. Overall, the galinstan based minichannel cooling is proven to be a powerful and practical way for the thermal management of high heat flux and large heat power devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel method for determining thermophysical properties of PCM is proposed. • Multiple properties can be obtained simultaneously in one test. • The measured results agree well with the data reported in the literature. • The method is simple, low cost and has high measurement speed. Abstract In this paper, a novel method for determining the main thermophysical properties of phase change materials (PCM) is proposed, which can be called as “T-melting CHF” method. The melting point, fusion latent heat, thermal conductivity, and specific heat capacity in both solid and liquid phase of PCM, can all be obtained simultaneously by only one test. The theoretical fundamentals lying behind are introduced, the measurement apparatus and measurement principles are presented, and corresponding restrictive conditions for high accuracy measurement are provided. Theoretically, the thermophysical properties can be accurately measured by the proposed method if the test module can be perfectly insulated. However, heat loss inevitably exists in practical measurement, it will significantly influence the measuring accuracy, hence a correction method is proposed to improve this situation. A typical low melting point metal (gallium) and a typical organic PCM (n-eicosane) were tested to verify the feasibility and accuracy of the method. The experimental results agree well with the reference data reported in the literature. Compared with conventional measurement techniques, the method proposed here has advantages such as simple structure, low cost and high measurement speed; more importantly, it is able to measure multiple properties simultaneously. [ABSTRACT FROM AUTHOR]

In this paper, a finned heat pipe assisted passive heat sink based on a newly emerging high performance phase change material (PCM), the low melting point metal (LMPM), was developed for thermal buffering of high power electronics which works intermittently with heat generation rate up to 1000 W (10 W/cm 2 ). Firstly, thermal performances of the PCM heat sink under different thermal shocks (from 200 W to 1000 W) were experimentally evaluated, in comparison with that of an organic PCM which has similar melting point. It was found that, the former one can prolong the working duration 1.4–2.4 times that of the latter one. Then, the performance of the heat sink was improved through reducing the contact thermal resistance and by increasing the fin number. Furtherly, an air cooling radiator was configured to accelerate the solidification process of the PCM module, which makes it capable of maintaining its highest temperature below 85 °C under 1000 W periodic thermal shock (10 min on and 15 min off). Moreover, energy dispersive spectrometer (EDS) analysis was conducted to verify the compatibility of the LMPM PCM and the structural materials. Finally, a simplified numerical model was developed and validated for the currently constructed finned heat pipe assisted LMPM PCM heat sink, which can be much helpful for future practical thermal design and optimization of this kind of thermal buffering module. [ABSTRACT FROM AUTHOR]

A double distribution function lattice Boltzmann method (LBM) with multirelaxation time is implemented to simulate the Rayleigh-Benard convection melting of a typical low-melting-point metal in a rectangular cavity. Typical cases frequently encountered in practice with constant heat flux/constant temperature boundary conditions are parametrically investigated, with corresponding dimensionless results outlined; the influence of inclination angle of the cavity is also clarified. The computational speed of the current LBM would reach about 40 times faster than that of conventional finite volume method as performed by commercial software Fluent. The obtained results would be valuable for guiding practical thermal design. [ABSTRACT FROM AUTHOR]

In this paper, low melting point metal (LMPM), eutectic alloy Bi 31.6 In 48.8 Sn 19.6 ( E -BiInSn), was adopted as phase change material for potential thermal management applications. First, E -BiInSn was prepared and its main thermophysical properties were characterized. Then, transient thermal performances of E -BiInSn based heat sinks with internal crossed fins were tested, in comparison with that of organic PCM (octadecanol) which has close melting point. Three types of heat sink structures which have different number of internal fins were studied. Three heating conditions were applied, namely 80 W (2.2 W/cm 2 ), 200 W (5.6 W/cm 2 ) and 320 W (8.9 W/cm 2 ). For all of the cases, E -BiInSn exhibited much superior thermal performance than that of octadecanol. Furthermore, cyclic test of the E -BiInSn heat sink was carried out, which showed good repeatability and stability, and without supercooling. Finally, a simplified 3D conjugate numerical model was developed to simulate the melting process of LMPM heat sink, which showed good agreement with the experimental results. This simplified model would be much useful in practical thermal design and optimization of LMPM heat sink, for that it would significantly save the computational time consumption. [ABSTRACT FROM AUTHOR]

Low melting point metals (LMPMs) are a new kind of phase change materials (PCMs) which exhibit excellent heat extraction capability due to their high thermal conductivity. Such a characteristic renders it distinctive melting mode which hardly exists in conventional paraffin PCMs. In this paper, comprehensive numerical investigation is carried out to reveal the melting process of LMPMs. First, comparative simulations of typical paraffin eicosane and typical LMPM gallium is conducted. Then, dimensionless analysis is performed based on a series of parametric studies and corresponding dimensionless correlations are given under both constant wall temperature condition and constant heat flux condition. Further, the critical dimensionless values within which the correlations are applicable are suggested. Finally, a preliminary exploration is performed to illustrate the influence of natural convection under relatively high Ra number condition. This study can serve as a valuable reference for future practical thermal design of LMPMs based thermal management systems and thermal energy storage systems. [ABSTRACT FROM AUTHOR]

Thermal management especially cooling of electric vehicles (EVs) battery pack is of great significance for guaranteeing the performance of the cells as well as safety and high-efficiency working of the EVs. Liquid cooling is a powerful way to keep the battery temperature in a proper range. However, the efficiency of conventional liquid cooling is still limited due to the inherently low thermal conductivity of the coolant which is usually water or aqueous ethanol. In this paper, a new kind of coolant, liquid metal, is proposed to be used for the thermal management of the battery pack. Mathematical analysis and numerical simulations are conducted to evaluate the cooling capability, pump power consumption and module temperature uniformity of the liquid metal cooling system, in comparison with that of water cooling. The results show that under the same flow conditions, a lower and more uniform module temperature can be obtained and less pump power consumption are needed in the liquid metal cooling system. In addition, liquid metal has an excellent cooling capability coping with stressful conditions, such as high power draw, defects in cells, and high ambient temperature. This makes it a promising coolant for the thermal management of high driving force EVs and quick charge batteries. [ABSTRACT FROM AUTHOR]

Thermal management especially cooling of electric vehicles (EVs) battery pack is of great significance for guaranteeing the performance of the cells as well as safety and high-efficiency working of the EVs. Liquid cooling is a powerful way to keep the battery temperature in a proper range. However, the efficiency of conventional liquid cooling is still limited due to the inherently low thermal conductivity of the coolant which is usually water or aqueous ethanol. In this paper, a new kind of coolant, liquid metal, is proposed to be used for the thermal management of the battery pack. Mathematical analysis and numerical simulations are conducted to evaluate the cooling capability, pump power consumption and module temperature uniformity of the liquid metal cooling system, in comparison with that of water cooling. The results show that under the same flow conditions, a lower and more uniform module temperature can be obtained and less pump power consumption are needed in the liquid metal cooling system. In addition, liquid metal has an excellent cooling capability coping with stressful conditions, such as high power draw, defects in cells, and high ambient temperature. This makes it a promising coolant for the thermal management of high driving force EVs and quick charge batteries. [ABSTRACT FROM AUTHOR]

Hydrogen is a kind of promising clean energy with huge potential values for human being. Developing a convenient real-time and on-demand hydrogen production and utilization method is critical for its wide practices. Liquid metal was recently found to be able to easily activate aluminum in aqueous solution to continuously and quickly generate hydrogen at room temperature, and thus provides a straightforward hydrogen production way. To further improve this technology, we are dedicated here to investigate the effects of the container substrate on such hydrogen generation process. An interesting phenomenon was found that metal substrate material would evidently enhance the hydrogen generation rate. For conceptual illustration purpose, comparative experiments were conducted to demonstrate the different hydrogen evolution modes between the present method and former approach, and the enhancement mechanism lying behind was revealed. In addition, the influence of the surface roughness of the substrate on the hydrogen production performance was also clarified. The present finding would help motivate an improved extremely simple, straightforward and low cost way for the liquid metal assisted aluminum hydrogen production. [ABSTRACT FROM AUTHOR]

The evolution of bubble structure and electron injection in laser wakefield acceleration with different optical cycles is investigated through three-dimensional particle-in-cell simulations. Under fixed transverse and longitudinal ponderomotive force, the effect of optical cycles on the evolution of bubble structure and electron injection is studied by changing the laser wavelength. For a multi-cycle laser, electron acceleration is dominated by the ponderomotive force that produces symmetrical bubble and continuous injection. As the optical cycles decrease, the dominant effect of the electron acceleration can transition from the ponderomotive force to the carrier wave, and the carrier envelope phase shift can cause transverse oscillation of the bubble and periodic electron injection in the direction of laser polarization. The criterion for the dominant acceleration mechanism and the dependence of transition distance on the optical cycles and pulse width are obtained. The results are beneficial for manipulating electron acceleration and betatron radiation generation. [ABSTRACT FROM AUTHOR]

Highlights: [•] MiR-106b is up-regulated in CAFs compared to NFs in gastric cancer. [•] Down-regulation of miR-106b in CAFs inhibits cancer cell motility by targeting PTEN. [•] MiR-106b might be a potential therapeutic target for gastric cancer. [Copyright &y& Elsevier]

Abstract: Three nematode-endoparasitic, Hirsutella rhossiliensis (18 isolates), Hirsutella minnesotensis (8 isolates) and Hirsutella vermicola (3 isolates) were studied for their variability in morphology, nematode parasitism, and DNA sequences of internal transcribed spacer (ITS) of ribosomal DNA (rDNA) and mitogen-activated protein kinase (MAPK) gene fragments. There were differences in length and width of conidiogenous cells and conidia among the three Hirsutella species and among isolates within species of H. rhossiliensis and H. minnesotensis. Most isolates of H. rhossiliensis and H. minnesotensis parasitized higher percentages of the cyst nematodes, Heterodera glycines and Heterodera avenae, than the four non-cyst nematodes, Meloidogyne hapla, Bursaphelenchus xylophilus, Heterorhabditis bacteriophora, and Steinernema carpocapsae. H. vermicola had no or weak parasitism on the six assayed nematode species. The phylogenetic trees of ITS region, MAPK gene fragments and their combination revealed that there was genetic variability among species and isolates, but there was no apparent relationship between the genetic variability and their host or geographic origin. [Copyright &y& Elsevier]

Based on a latest finding on Al-water reaction, we studied the hydrogen production behaviors activated by gallium based liquid metal where the mass percentage of Al was less than 1% in an alkaline environment. Three kinds of room temperature liquid binary alloy including Ga–In, Ga–Sn and Ga–Zn were tested and compared with pure gallium. It was shown that the hydrogen production rate activated by Ga–In alloy was far below than that of pure gallium, while Ga–Sn and Ga–Zn run slightly slower. Aiming to optimize the catalytic performance of pure gallium, we further performed researches to clarify its practical features. We divided five times to add equivalent Al block into pure gallium and found that the rate and quantity of hydrogen production kept unchanged in each batch addition, which suggested that liquid metal as catalyst was activated continuously without impurities mixing to impede catalytic effect. In addition, components analysis of the residual precipitates after reaction with XRD also indicated that there was only Al(OH) 3 but no gallium or its derivatives. These findings as clarified by this article can help guide future high performance hydrogen generation and reuse of the liquid metal catalyst. [ABSTRACT FROM AUTHOR]

Space radiation with inherently broadband spectral flux poses a huge danger to astronauts and electronics on aircraft, but it is hard to simulate such feature with conventional radiation sources. Using a tabletop laser-plasma accelerator, we can reproduce exponential energy particle beams as similar as possible to these in space radiation. We used such an electron beam to study the electron radiation effects on the surface structure and performance of two-dimensional material (FePS3). Energetic electron beam led to bulk sample cleavage and damage between areas of uneven thickness. For the FePS3 sheet sample, electron radiation transformed it from crystalline state to amorphous state, causing the sample surface to rough. The full widths at the half maximum of characteristic Raman peaks became larger, and the intensities of characteristic Raman peaks became weak or even disappeared dramatically under electron radiation. This trend became more obvious for thinner samples, and this phenomenon was attributed to the cleavage of Pâ€"P and Pâ€"S bonds, destabilizing the bipyramid structure of [P2S6]4â€" unit. The results are of great significance for testing the maximum allowable radiation dose for the two-dimensional material, implying that FePS3 cannot withstand such energetic electron radiation without an essential shield. [ABSTRACT FROM AUTHOR]

A new scheme is proposed to improve the electron beam quality of ionization-induced injection by tailoring gas profile in laser wakefield acceleration. Two-dimensional particle-in-cell simulations show that the ionization-induced injection mainly occurs in high-density stage and automatically truncates in low-density stage due to the decrease of the wakefield potential difference. The beam loading can be compensated by the elongated beam resulting from the density transition stage. The beam quality can be improved by shorter injection distance and beam loading effect. A quasi-monoenergetic electron beam with a central energy of 258 MeV and an energy spread of 5.1% is obtained under certain laserâ€"plasma conditions. [ABSTRACT FROM AUTHOR]

OMSL is a passive, space-based spectrometer designed to obtain the vertical profiles of trace gases such as ozone, by measuring atmospheric radiation in limb-viewing mode. Due to the presence of internal components such as gratings and dichroic mirror, OMSL is sensitive to polarization of incident light, which can lead to errors in the radiometric measurements, especially when the incident light is fully polarized. To eliminate the errors, an on-orbit polarization correction method is applied to OMSL. The key to this method is to calculate the polarization correction factor by combining the on-orbit polarization measurement and the pre-flight polarization calibration. In this paper, the on-orbit polarization correction method is introduced in detail. Furthermore, the first results of the on-orbit correction are analyzed and compared with simulation of the SCIATRAN. • An on-orbit polarization correction method is introduced to reduce measurement errors. • The key to this method is to calculate the on-orbit polarization correction factor. • The first on-orbit correction is analyzed and compared with SCIATRAN simulation. • The polarization correction method is a good reference for hyperspectral instruments. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to construct a nomogram that will predict the overall survival (OS) of hepatocellular carcinoma (HCC) patients after transarterial chemoembolization (TACE).Materials and Methods: Imaging data, clinical characteristics, and serum des-γ-carboxy prothrombin (DCP) levels of 93 HCC patients treated with TACE were collected. Lasso regression, random forest, and other methods were used to screen the OS-related variables and construct the Cox prognosis model. The model was visualized by nomogram, and the net benefit of the clinical decision was assessed by decision curve analysis (DCA).Results: It was found that DCP level after TACE was an important predictor of OS in HCC patients. The OS of the patients with lower serum DCP levels after TACE was significantly better than the group with higher levels (P = 0.003). The Cox prognostic model was constructed using four predictors including DCP reactivity (P = 0.001), modified Response Evaluation Criteria in Solid Tumors (mRECIST, P = 0.005), Child-Pugh class (P = 0.018), and portal vein thrombosis (P = 0.039). The C-index of the nomogram for OS of patients after TACE was 0.813. The clinical decision-making net benefits based on the nomogram were better than the decision-making based on the TNM stage system.Conclusion: DCP reactivity and mRECIST are the key predictors of prognosis in HCC patients that received TACE as their initial treatment. The nomogram constructed with these two indicators as the core could predict the OS of HCC patients after TACE and help in clinical decision-making. [ABSTRACT FROM AUTHOR]

A scheme for generating high-flux positrons by two counter-propagating laser pulses colliding in near-critical-density plasmas is proposed, which might be realized with current laser facilities. Positrons of number 2.79 × 105 and with a maximum density of 9.63 × 1024 m−3 can be generated for a laser with an intensity of 1022 W cm−2. This is attributed to the increase in the cross sections for photon radiation and positron generation in the colliding scheme. In order to improve the positron generation, the relevant parameters are discussed in detail. This scheme will facilitate the observation of the Breit-Wheeler positrons in the laboratory. [ABSTRACT FROM AUTHOR]

• A novel integrated cooling modality was introduced and investigated. • The calculation model of fluid-solid heat transfer process coped with phase change in the packed bed was established. • The thermal management ability of composite heat sink under typical conditions has been revealed. • The influences of different stacking patterns and operating parameters on the heat transfer enhancement in the packed bed were analyzed. This paper is dedicated to investigate the integrated cooling modality that the spherical low melting point metal (LMPM) macrocapsules were introduced and filled as phase change material (PCM) into a convective cooling heat sink. The fluid-solid heat transfer process coupled with phase change in the packed bed was numerically calculated based on the local thermal non-equilibrium theory and the effective specific heat capacity model which were validated in advance by conceptual experiments. The thermal management ability of composite heat sink packed with spherical LMPM-PCM macrocapsules under typical operating conditions has been revealed. In addition, the influences of different stacking patterns of LMPM particles, particle diameter and inlet velocity on the heat transfer enhancement in the packed bed were comprehensively investigated, respectively. It is found that compared with convective cooling heat sink alone, the composite heat sink filled with LMPM-PCM macrocapsules presents excellent thermal management performance. The temperature increment of heat source in the pulse heat load is reduced by 73.4%, which fully demonstrates the advantages of filling spherical particles. Besides, the Orthoclinal Stacking method achieves the largest volumetric heat transfer coefficient among different stacking patterns of equal-diameter spherical LMPM-PCM macrocapsules. What is more, the plateau duration of the solidification is gradually shortened with the decreasing diameter of the spherical LMPM-PCM macrocapsules and the increasing inlet velocity, which is advantageous for the system to quickly rehabilitate to normal operating temperatures during the de-pulse stage. Overall, this novel integrated cooling modality is proven to be a powerful and practical way to sustain extreme thermal management challenge. [ABSTRACT FROM AUTHOR]

Application of π-multilayer technology is extended to high extinction coefficient materials, which is introduced into metal-dielectric filter design. Metal materials often have high extinction coefficients in far ultraviolet (FUV) region, so optical thickness of metal materials should be smaller than that of the dielectric material. A broadband FUV filter of 9-layer non-periodic Al/MgF2 multilayer was successfully designed and fabricated and it shows high reflectance in 140-180 nm, suppressed reflectance in 120-137 nm and 181-220 nm. [ABSTRACT FROM AUTHOR]

A new scheme of radiation pressure acceleration for generating high-quality protons by using two overlapping-parallel laser pulses is proposed. Particle-in-cell simulation shows that the overlapping of two pulses with identical Gaussian profiles in space and trapezoidal profiles in the time domain can result in a composite light pulse with a spatial profile suitable for stable acceleration of protons to high energies. At ∼2.46 × 1021 W/cm2 intensity of the combination light pulse, a quasi-monoenergetic proton beam with peak energy ∼200 MeV/nucleon, energy spread <15%, and divergency angle <4° is obtained, which is appropriate for tumor therapy. The proton beam quality can be controlled by adjusting the incidence points of two laser pulses. [ABSTRACT FROM AUTHOR]