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This paper investigates the mystery of baryogenesis for isotropic and anisotropic universe models in the context of Rastall's theory of gravity (RTG). In the first part, we utilize the Rastall field equations (FEs) for the flat Friedmann Robertson Walker (FRW) metric to find the solutions of density ρ and Hubble parameter H. Additionally, Rastall parameter plays a crucial role to discuss baryogenesis and fulfilling its criteria on the observational ground. It is found that very large positive/negative values of Rastall parameter like λ ≥ 1 0 5 4 (for ω = 0) and λ ≤ − 1 0 2 2 (for ω = 1) are required to satisfy the observational bounds on baryon asymmetry factor (BAF), see Fig. 1. In the second part, we develop the FEs for RTG using the Locally Rotationally Symmetric (LRS) Bianchi type-1 line-element. Then we find the solutions of the FEs and use them to find the BAF using Rastall parameter as λ ≤ − 1 0 3 7 and anisotropic parameter n ≥ 2 to meet the consistency with the experimental limit, see Fig. 3. For n = 1 , the anisotropic model reduces to the isotropic FRW model, where we have a zero BAF. Finally, we conclude that RTG with both universe models is a good candidate to study baryogenesis in the early universe and the variable λ has a considerable impact on the BAF. [ABSTRACT FROM AUTHOR]

In this paper, Er3+ doped TeO 2 -ZnF 2 -BaF 2 -KF-Ta 2 O 5 tellurite glasses with low hydroxyl content (∼0.03 × 10−19 cm−3) were investigated employing both glass composition and glass melting process optimization. The Raman spectra and physical properties were characterized to analyze the structure of the glasses. Under the pumping of 980 nm LD laser, intense up-conversion fluorescence at 1.5 and 2.7 μm of samples and their lifetimes were detected and analyzed, and the related transition mechanisms with gradient-varying Er3+ doping concentrations were discussed. The maximum absorption and emission cross section at 2.7 μm was calculated to be 6.4 × 10−21 cm2 and 6.8 × 10−21 cm2, correspondingly, which were higher than those of traditional tellurite glasses. Using the calculated and measured spectroscopic parameters of bulk tellurite glass, a dual-wavelength pumping model was established to verify the feasibility of mid-infrared laser output in similar tellurite glass fiber. Experimental results support the assertion that the Er3+ doped tellurite glasses hold promise as a candidate laser gain medium for mid-infrared fiber laser systems. [ABSTRACT FROM AUTHOR]

This paper is the editorial for the virtual special issue (VSI) of Renewable and Sustainable Energy Reviews (RSER) dedicated to three Sustainable Development of Energy Water and Environment Systems (SDEWES) Conferences held in 2022, namely: (i) the 5th South East European Conference SEESDEWES 2022 held from May 22 to 26, 2022 in Vlore, Albania; (ii) the 3rd Latin American LASDEWES 2022 held from July 24 to 28, 2022 in Sao Paulo, Brazil and (iii) the 17th SDEWES 2022 held from November 6 to 10, 2022 in Paphos, Cyprus. The VSI collected both high quality review papers and original research articles presented at these conferences, aligning with the aims and scope of RSER. Following a rigorous peer review process, seventeen articles were accepted and published. These articles explore techniques and technologies essential for advancing feasible Renewable and Sustainable Energy Systems. Spanning multidisciplinary topics, many of them address almost all the Sustainable Development Goals, offering feasible solutions for much-needed decarbonization pathways. • The VSI SDEWES 2022 presents the ready solutions for Renewable and Sustainable Energy Systems. • Five clusters for presenting the Renewable and Sustainable energy cutting edge solutions. • The positioning in the scientific context of the Renewable and Sustainable Energy Systems. • Feasible solutions for much-needed decarbonization pathways. [ABSTRACT FROM AUTHOR]

• The effect of protective layer on the performance of smart radiation devices is comprehensively evaluated. • The emission regulation can be enhanced to 0.65, while the solar absorption can be decreased to 0.18. • The performance of the proposed SRD meets the requirement of the spacecraft thermal control devices. • This work provides a theoretical basis for the design of more reasonable spacecraft thermal control devices. With the arrival of the space economy, the miniaturization of spacecraft and their multi-functional trends have put a greater demand on space thermal control systems. Smart radiation devices (SRDs) are gaining attention as a low-cost, light-weight material for the thermal control of spacecraft. Previous works have focused on how to enhance IR emittance tunability of SRDs. In fact, the SRDs performance and lifetime may be affected by the external space environment. Thus, researchers proposed to cover the SRDs with a protective layer to resist oxidation and other problems. However, the influence of protective layer on the performance of SRDs, including IR emittance tunability Δ ε and solar absorption α s , has not been studied systematically yet. In this paper, the impact of protective layer on the performance of SRDs is comprehensively evaluated in theory. Firstly, a three-layer SRD is composed of a vanadium dioxide (VO 2) film, BaF 2 , and a silver (Ag) substrate, which is optimized using the transfer matrix method. The IR emittance tunability and solar absorption can reach 0.64 and 0.29, respectively. Secondly, the smart thermal control device with three protection materials (BaF 2 , Al 2 O 3 and Si) is investigated. The results show that the performance of SRD can be enhanced or deteriorated, depending on the types of protection materials and the thickness. When the protection material is Si, the IR emittance tunability can be enhanced to 0.65, while the solar absorption can be decreased to 0.18. The performance of the proposed SRD meets the requirement of the spacecraft thermal control devices. We believe that this work provides a theoretical basis for the design of more reasonable spacecraft thermal control devices. [ABSTRACT FROM AUTHOR]