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Abstract: The development of computers and the internet have made distance learning easier and faster. In this field, remote laboratories are enabling intensive use of university facilities, while aiding the work of professors and students. The paper introduces a remote laboratory designed to be used in PLC practical work. The relative experiments are described The students can complete the programming exercises at different location and different time on campus. The evaluation is conducted and the experience has proved to be positive, and the students have valued it accordingly. [Copyright &y& Elsevier]

Currently, numerous studies are devoted to the pursuit of thermal conductivity enhancement of phase change materials (PCMs). On the contrary, few researches are reported to reduce the thermal conductivity of PCMs. Generally, the PCMs with reduced thermal conductivity have great potential in thermal protection application. Herein, we propose a novel in situ one-step strategy to facilely prepare monolithic silica aerogel-based composite PCMs. The silica aerogels possess low thermal conductivity and are used to encapsulate PCMs to prepare composite PCMs, such as polyethylene glycol (PEG) or octadecanol. Compare with PEG2000@silica aerogel, the resulting monolithic octadecanol@silica aerogel have low thermal conductivity (0.12 W m−1 K−1), high latent heat (127.73 J/g), large compressive strength (11 MPa), good hydrophobicity (contact angle 124°) and superior thermal cycling stability. This monolithic silica aerogel-based composite PCMs could prolong heat preservation duration due to the synergistic effect between low thermal conductivity and high latent heat of composite PCMs, showing potential promise for direct application to the thermal insulation and thermal protection device. More importantly, this in situ one-step synthesis strategy is universal for different types of PCMs. Image 1 • An in situ one-step strategy was proposed to synthesize monolithic silica aerogel-based composite PCMs. • This in situ one-step strategy is universal for the encapsulation of diverse PCMs. • Monolithic silica aerogel-based composite PCMs possess excellent shape stability and high compressive strength (11 MPa). • The silica aerogel-based composite PCMs have low thermal conductivity (0.12 W m−1 K−1) and high latent heat (127.73 J/g). [ABSTRACT FROM AUTHOR]

• Hierarchical Co-embedded porous carbon microspheres were controllably synthesized. • The Co-based catalyst showed superior performance beyond noble-metal-based catalysts. • The partially uncovered and totally in-built Co species were likely the active sites. The direct pyrolysis of metal organic frameworks (MOFs) has recently provided an effective method to prepare various metal-incorporated composite carbon materials. In this work, hierarchical Co-embedded N-doped porous carbon microspheres were synthesized by controlled pyrolysis of bimetallic Zn-Co Prussian blue analogues (PBAs), in which the metallic Zn component served as thermally removable template and ligand [Co(CN) 6 ]3− served as both Co and N sources. When devoted to catalyzing the reduction of 4-nitrophenol (4-NPh) into 4-aminophenol (4-APh), the optimized catalyst exhibited a large apparent rate constant of 1.35 min−1 and high turnover frequency (TOF) of 0.0204 s−1, which was superior to the majority of noble-metal-based catalysts. Besides, a home-made continuous flow catalysis system was readily constructed. Control experiments confirmed that both partially uncovered and totally in-built active metallic Co species acted as catalytically active sites. This work might provide a further understanding of the identification of active sites within metal-incorporated carbon-based catalysts. [ABSTRACT FROM AUTHOR]

Highlights: [•] Simple approach to fabricate OANI superstructures with controllable morphology. [•] Stable pH value to form the uniform morphologies. [•] Investigate the forming mechanism for the complex morphologies of OANI. [Copyright &y& Elsevier]

Energy storage capacity and heat transfer ability are two important indexes for shape-stabilized phase change materials (ss-PCMs). In this paper, a core-sheath CNT@PC was prepared via carbonation of CNT@ZIF-8, simultaneously 3D structural supports were obtained due to the porous carbon (PC) sheath stabilized the CNT@PC network structure. Porous carbon (PC), derived from carbonized metal organic frameworks (MOFs), exhibited high porosity and large specific surface area. PCMs, absorbed by capillary force of porous structure, was stabilized in the pores of PC sheath. Further, the interaction between PCMs and CNTs reduced the interfacial thermal resistance greatly. Carbon nanotubes (CNTs), acting as heat transfer pathways, provided continuous channels for phonons transfer and realized rapid heat transformation between ss-PCMs and external environment. The obtained SA/CNT@PC ss-PCMs exhibited excellent thermal conductivity (1.023 W/mK), large phase change enthepy (155.7 J g −1 ) and high thermal storage capabilities (99.9%). The thermal conductivity of SA/CNT@PC was improved 222.6% and phase change enthalpy was increased 92.6% over SA/PC ss-PCM. SA/CNT@PC with large energy storage density, flexible designation, simple operation and near-constant temperature properties during phase change process shows great potential in waste heat utilization. [ABSTRACT FROM AUTHOR]

A systematic mesoporous N-doped carbons/myristic acid-stearic acid composite materials with improved thermal conductivity, energy storage density and shape stable performance were prepared by encapsulating myristic acid-stearic acids (MA-SA) eutectic mixture into porous carbon matrixes derived from two synthesis strategies. The effect of synthesis strategies and the N species present in porous carbons on the microstructure and thermal energy storage properties of composite phase change materials were studied by various characterization techniques. The results indicated that N-doped porous carbons derived from in situ (NPC) had maximum of up to 88 wt% PCM loading with a melting latent heat of 164.33 ± 0.29 kJ/kg, which was up to 45.69% higher than that of composite PCMs by post synthesis route (MGC/MA-SA). Factors, like pore characteristics, capillary force, surface tension and additional interaction with N species present in carbon matrix played vital roles for encapsulation of MA-SA to the pores of supporting materials. Notably, NPC/MA-SA composite materials exhibited excellent thermal conductivity, 117.65% higher than pristine PCM, while 74.59% for MGC/MA-SA. The content, homogeneous distribution and graphitic nature of N as well as the interconnected porous carbons improves the heat transfer pathways in the composite PCMs during phase change process. All the prepared samples were thermally and chemically compatible even after 100 times thermal cycling, confirming that the prepared composite materials were a promising candidates for thermal management system in a medium phase transition temperatures like domestic solar hot water supply and air-conditioning purposes. [ABSTRACT FROM AUTHOR]

Nanosheets with large exposed surface and high chemical activity are of paramount significance for catalysis, gas sensing and energy storage. However, assembling them into large-area free-standing films and preventing aggregation of individual nanosheets remain a great challenge. Herein, an efficient strategy is proposed to assemble defect-rich TiO 2 (B) nanosheets into a 3D-scaffold structured free-standing film, which can preserve high chemical activity and prevent their aggregation. The inherent pores of Teflon lining are employed as load-bearing base to construct 3D scaffolds, and then, a rapid dissolution-recrystallization hydrothermal process is developed to fabricate defect-rich TiO 2 (B) nanosheets (~5 nm in thickness) on the 3D scaffolds. The numerous defects are crucial for boosting high rate performance within LIBs. The hierarchical 3D-scaffold structure endows the nanosheets-based electrode with outstanding cycling stability (96.1% retention after 6000 cycles at 6.7 A g−1), which hits a record high in terms of capacity retention for TiO 2 (B) nanosheets at high rate. The strategy for fabricating and assembling defect-rich TiO 2 (B) nanosheets paves the way for high performance LIBs. Image 1 • A template-free hydrothermal method is employed to construct 3D-scaffold structure. • Defect-rich TiO 2 (B) nanosheets-based free-standing film is successfully obtained. • The defect-rich nanosheets-based electrode exhibits outstanding cycling stability. [ABSTRACT FROM AUTHOR]