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As ASEAN countries, including Vietnam, approach the living standards of developed countries, their copper demand is set to rise. This study investigates Vietnam's copper stock and flow from 1995 to 2050, employing dynamic material flow analysis and five socioeconomic pathway scenarios (SSPs). Based on this, the secondary copper reserves of Vietnam were assessed. The results showed that the domestic copper demand is expected to grow to 526–1062 kt, resulting in a rapid increase in scrap generation. In 2022, Vietnam's secondary copper reserves stood at 2.2 Mt and are projected to reach 6.8–8.6 Mt by 2050 under the SSP2 scenario. This corresponds to 3.6–4.6 times the 1.8 Mt primary copper reserve of Vietnam. However, these primary and secondary reserves cannot meet the cumulated demand by 2050. On the other hand, a large amount of copper, 8.9 Mt to 10 Mt, will become difficult-to-recover resources, such as waste in landfill sites, dissipated materials, or mixed metal loss. To promote the sustainable use of copper in Vietnam, we recommend increased geological expedition and mining investment, and improved waste management systems related to secondary resources. [ABSTRACT FROM AUTHOR]

Smelting of copper, a crucially important resource, releases small amounts of mercury into the atmosphere, thereby endangering people and the global environment. This study estimated the expected changes in mercury emissions from copper smelting in response to future changes in copper demand in major copper-producing countries (China, DR Congo, Germany, Iran, Japan, Russia, South Korea, and the USA). Then it evaluated the expected effects of copper recycling promotion and mercury removal technology introduction on emissions. Results indicate that (1) the total expected copper demand of the major countries in 2050 is 15.9 Mton. (2) Under a business-as-usual scenario, the total atmospheric mercury emissions from major countries will be 36% greater than the 2022 estimate. However, promoting copper recycling and introducing mercury removal technologies can reduce that by 99.3%. (3) China, Russia, and Iran account for about 98% of 2022 total mercury emissions from copper smelting in the major countries. The introduction of mercury removal technologies in these countries is expected to have considerable reduction effects. (4) Changes in copper ore grades can cause atmospheric mercury emissions to fluctuate. Overall, these findings highlight the potential risks of increased atmospheric mercury emissions and underscore the importance of implementing effective countermeasures to mitigate these risks. [ABSTRACT FROM AUTHOR]

A floating signage which means optical images are floating in the air is one of the useful ways to attract people's attention. Since 2019, our research group proposed unidirectional observable aerial signage display using thin film layers or dye-dopedoptical prisms to avoid mirrored imaging problem which means observers end up watching wrong messages or images from back side. In this paper, the authors describe the aero signage using quasi-spatial floating image and how to generate floating images using optical illusion and to control light paths. [ABSTRACT FROM AUTHOR]

In eukaryotic cells, loosening of chromatin causes changes in transcription and DNA replication. The artificial conversion of tightly packed chromatin (heterochromatin) to loosely packed chromatin (euchromatin) enables gene expression and regulates cell differentiation. Although some chemicals convert chromatin structures through histone modifications, they lack sequence specificity. This study attempted to establish a novel technology for inducing chromatin loosening in target regions of Saccharomyces cerevisiae. We focused on histone acetylation, which is one of the mechanisms of euchromatin induction. The sequence-recognizing ability of the dead Cas9 (dCas9) and guide RNA (gRNA) complex was used to promote histone acetylation at a targeted genomic locus. We constructed a plasmid to produce a fusion protein consisting of dCas9 and histone acetyltransferase Gcn5 and a plasmid to express gRNA recognizing the upstream region of heterochromatic URA3. Confocal microscopy revealed that the fusion proteins were localized in the nucleus. The yeast strain producing the fusion protein and gRNA grew well in the uracil-deficient medium, while the strain harboring empty plasmids or the strain containing the mutations that cause loss of nucleosomal histone acetylation activity of Gcn5 did not. This suggests that the heterochromatin was loosened as much as euchromatin through nucleosomal histone acetylation. The amount of euchromatic DNA at the target locus increased, indicating that chromatin loosening was induced by our system. Nucleosomal histone acetylation in heterochromatic loci by our developed system is a promising method for inducing euchromatic state in a target locus. [ABSTRACT FROM AUTHOR]

The distribution of nano‐sized silica in binary rubber blends is characterized by scanning transmission electron microscopy (STEM) tomography combined with energy dispersive X‐ray spectrometry (EDX). 3D distribution of silica is visualized by STEM‐EDX tomography with the tilt‐series of silicon elemental maps, while the phase‐separated morphologies of polyisoprene rubber (IR) and styrene‐butadiene rubber (SBR) are visualized by STEM‐tomography in high‐angle‐annular‐dark field (HAADF) mode. The combination of STEM‐EDX and STEM‐HAADF tomography enables us to determine the distribution of silica between the two rubber phases quantitatively even with high contents of silica up to 70 phr (weight parts per hundred rubber). It is found that silica is preferentially distributed in the SBR phase, but it is also distributed in the IR phase when the IR fraction in the total rubber components is higher than 40 wt%. The preferential distribution of silica in the SBR phase improves the dispersion of the IR domains. This is the first use of this technique for a multicomponent polymer system, showing the advantage to characterize the complicated multicomponent polymer composite morphologies. [ABSTRACT FROM AUTHOR]

A composite structure of piezoelectric particles and soft polymer composite materials is a promising component of vibration energy harvesters. However, the energy harvesting behavior which originates from ceramic particles inside the polymer has not been clarified. In this study, (Na,K)NbO3/polyimide composites sheets with NKN fraction of 0–40 vol% were fabricated and open-circuit voltage was measured. The open-circuit voltage was increased nonlinearly from 0.72 to 2.21 V with increasing of the particle fraction (10%–30%) The experimental results were confirmed using a microstructure based finite element method and electric potential and electromechanical coupling coefficients were higher value in the content of 30% NKN particles. Analysis indicates that the internal electric potential inside the matrix under strain could be an important factor for macroscopic piezoelectric constant and electrical output. [ABSTRACT FROM AUTHOR]

The metal-free reduction of nitroarenes to aniline derivatives was accomplished in a short time by using a benzothiazoline as the hydrogen donor in combination with a Brønsted acid. An enantioselective synthesis of 2-arylquinolines was achieved by using 1-aryl-3-(2-nitrophenyl)propan-1-ones as starting materials and a combination of a benzothiazoline and a chiral phosphoric acid. [ABSTRACT FROM AUTHOR]

ABSTRACT There is a substantial need for photopattern-able, heat resistant, and transparent materials that are applicable to electronic devices, such as imaging or display elements. Styryl silsesquioxane based photoresist forms thin micro patterns after i-line exposure and alkaline development, and the resulting transparent film shows remarkable heat resistance. Radicals generated from a photoinitiator induce polymerization of styryl functionality in the photoresist film to form the micropatterns. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41459. [ABSTRACT FROM AUTHOR]

The cover image by Shin Horiuchi and co-authors shows how the distribution of nano-sized silica in binary rubber blends is characterized by scanning transmission electron microscopy (STEM) tomography, combined with energy dispersive X-ray spectrometry (EDX). The phase-separated morphologies of polyisoprene rubber (IR) and styrene-butadiene rubber (SBR) meanwhile is visualized by STEM-tomography in high-angleannular-dark field (HAADF) mode. The combination of STEM-EDX and STEM-HAADF tomography determines the distribution of silica between the two rubber phases quantitatively. [Extracted from the article]