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Battery thermal management system (BTMS) is very critical to a high-performance electric vehicle. Compared with other cooling methods, the immersion cooling with heat transfer efficiency has received comprehensive attentions recently, especially that with single-phase insulating oil, since it can not only guarantee the heat transfer efficiency but also simplify the system. This article reviews the latest research progress in oil-immersed BTMS based on single-phase insulating oil. Firstly, the development of insulating oils is introduced, and their basic cooling properties are compared and analyzed. Then, the influences of different factors on the effectiveness of the oil-immersed battery cooling system are analyzed from the aspects of immersion degree, flow channel configuration, thermal property parameters, and others. Finally, challenges with using insulating oil as the immersion cooling medium for lithium batteries (LIBs) are discussed, and potential future research directions are outlined. Ultimately, the insights of this paper will hopefully provide some references for researchers to further develop and design more efficient and reliable BTMSs, thus driving the development of LIBs. [ABSTRACT FROM AUTHOR]

In this work, we fabricated a polycrystalline Tb2FeCrO6 double perovskite (DP) oxide by a solid-state reaction method and determined its structural, magnetic, and magnetocaloric (MC) properties. The Tb2FeCrO6 DP oxide was found to crystallize in a DP-type structure with the Pbnm space group and to undergo a paramagnetic-to-antiferromagnetic transition at a temperature of ~ 8.5 K. A large low-temperature MC effect was observed in the Tb2FeCrO6 DP oxide. The MC parameters in terms of maximum magnetic entropy changes, temperature-averaged entropy change (5 K), and relative cooling power for Tb2FeCrO6 DP oxide under a magnetic field change of 0–7 T were 12.9 J/kg K, 12.7 J/kg K, and 341.4 J/kg, respectively. These parameters were consistent with similarly high levels in recently updated MC materials, making the material a suitable candidate for low-temperature magnetic cooling applications. [ABSTRACT FROM AUTHOR]

The performance of lithium-ion batteries is closely related to temperature, and much attention has been paid to their thermal safety. With the increasing application of the lithium-ion battery, higher requirements are put forward for battery thermal management systems. Compared with other cooling methods, liquid cooling is an efficient cooling method, which can control the maximum temperature and maximum temperature difference of the battery within an acceptable range. This article reviews the latest research in liquid cooling battery thermal management systems from the perspective of indirect and direct liquid cooling. Firstly, different coolants are compared. The indirect liquid cooling part analyzes the advantages and disadvantages of different liquid channels and system structures. Direct cooling summarizes the different systems' differences in cooling effectiveness and energy consumption. Then, the combination of liquid cooling, air cooling, phase change materials, and heat pipes is examined. Later, the connection between the cooling and heating functions in the liquid thermal management system is considered. In addition, from a safety perspective, it is found that liquid cooling can effectively manage thermal runaway. Finally, some problems are put forward, and a summary and outlook are given. [ABSTRACT FROM AUTHOR]

Single crystalline BaMnSb2 is considered as a 3D Weyl semimetal with the 2D electronic structure containing Dirac cones from the Sb sheet. We report experimental investigation of low-temperature cleaved BaMnSb2 surfaces using scanning tunneling microscopy/spectroscopy and low energy electron diffraction. By natural cleavage, we find two terminations: one is Ba (above the orthorhombically distorted Sb sheet) and another Sb2 (at the surface of the Sb/Mn/Sb sandwich layer). Both terminations show the 2 × 1 surface reconstructions, with drastically different morphologies and electronic properties, however. The reconstructed structures, defect types and nature of the electronic structures of the two terminations are extensively studied. The quasiparticle interference (QPI) analysis is conducted at the energy range between −2 V and 2 V, although no interesting states are observed near the Fermi level, the surface-projected electronic band structures strongly depend on the surface termination above 1.6 V. The existence of defects can greatly modify the local density of states to create electronic phase separations on the surface in the order of tens of nm scale. Our observation on the atomic structures of the terminations and the corresponding electronic structures provides critical information towards an understanding of topological properties of BaMnSb2. [ABSTRACT FROM AUTHOR]

Data science teams often collaboratively analyze datasets, generating dataset versions at each stage of iterative exploration and analysis. There is a pressing need for a system that can support dataset versioning, enabling such teams to efficiently store, track, and query across dataset versions. We introduce OrpheusDB, a dataset version control system that "bolts on" versioning capabilities to a traditional relational database system, thereby gaining the analytics capabilities of the database "for free." We develop and evaluate multiple data models for representing versioned data, as well as a lightweight partitioning scheme, LyreSplit, to further optimize the models for reduced query latencies. With LyreSplit, OrpheusDB is on average 10 3 × faster in finding effective (and better) partitionings than competing approaches, while also reducing the latency of version retrieval by up to 20 × relative to schemes without partitioning. LyreSplit can be applied in an online fashion as new versions are added, alongside an intelligent migration scheme that reduces migration time by 10 × on average. [ABSTRACT FROM AUTHOR]

Shortest path is a fundamental graph problem with numerous applications. However, the concept of classic shortest path is insufficient. In this paper, we study various concepts of “shortest” path in temporal graphs, called minimum temporal paths. Computing these minimum temporal paths is challenging as subpaths of a “shortest” path may not be “shortest” in a temporal graph. We propose efficient algorithms to compute minimum temporal paths and verified their efficiency using large real-world temporal graphs. [ABSTRACT FROM PUBLISHER]

We propose two dynamic bandwidth allocation (DBA) algorithms by considering three dimensions, i.e., time slot, subcarrier, and bit allocation, to minimize the transmitting power of optical network units (ONUs) in orthogonal frequency division multiplexing access passive optical networks (OFDMA-PONs). In the first proposed algorithm, we make use of the three-dimensional DBA algorithm from wireless OFDM, modify it according to the characteristics of the fiber channel, and apply it to upstream access in OFDMA-PONs to reduce the transmitting power of ONUs. In order tofurther minimize the total transmitting power, we propose the second algorithm by allocating the subcarrier and bit in the same procedure. The complexity of the two proposed algorithms was evaluated by polynomial time. From simulation results, the transmitting power of ONUs under a certain bit error rate is reduced by ~30% and ~50% using the first and the second proposed algorithms, respectively, compared with the traditional two-dimensional DBA algorithm in OFDMA-PONs. [ABSTRACT FROM PUBLISHER]

This study was focused on extraction, radical scavenging activities, and chemical composition identification of total flavonoids in sunflower (Helianthus annuus L.) receptacles (TFSR). We investigated the optimal extract parameters of TFSR using response surface methodology. The highest yield of TFSR was 1.04% with the ethanol concentration 58%, the material-to-liquid ratio 1:20 (v/w), the extraction time 2.6 h, and the extraction temperature 67 °C. The results of radical scavenging activities showed that ethyl acetate fraction (EAF) was the strongest by using 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2'-azino-bis (3-ethylbenzo thiazoline-6-sulfonic acid) (ABTS) and iron ion reducing analysis. The EAF had the highest flavonoids contents. Four fractions A, B, C and D were enrichment from EAF by polyamide resin. Fraction B had the highest flavonoids content. Thirteen chemical components of flavonoids in fraction B were first identified by Ultimate 3000 Nano LC System coupled to a Q Exactive HF benchtop Orbitrap mass spectrometer (UHPLC-HRMS/MS). Among of the thirteen chemical components, isoquercetin and daidzein were identified accurately by comparing with standard samples. Radical scavenging analysis showed that isoquercetin and EAF had strong activities. Therefore, sunflower receptacles can be used as a source of natural flavonoids. TFSR as a natural radical scavenger has potential applications in pharmaceutical industry. [ABSTRACT FROM AUTHOR]