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• Corrosion of three molten-salt mixtures were studied at 700 °C under argon. • Four alloys were tested and characterized by SEM, EDS and XRD. • C276, In625 and In718 are compatible with the NaKZn chloride-salt. • SS316 and In718 show low corrosion in the LiNaK carbonate-salt. • C276, In625 and In718 are compatible with the LiF-NaK carbonate-salt. Molten eutectic salt mixtures can be used as thermal energy storage materials or heat transfer fluids at concentrated solar power plants. The targeted operating temperature for the next generation concentrated solar power plants is 700 °C. Although chloride and carbonate eutectic salt mixtures with high thermally stable temperatures were reported to have great thermophysical properties, their corrosion to alloys at high temperature has not been thoroughly studied. Corrosion of the thermal energy storage materials and heat transfer fluids to alloys is critical, and oxygen in air is confirmed to accelerate the corrosion significantly. In the present study, three eutectic mixtures of NaCl-KCl-ZnCl 2 , Li 2 CO 3 -Na 2 CO 3 -K 2 CO 3 and LiF-Na 2 CO 3 -K 2 CO 3 were considered as high temperature thermal energy storage materials or heat transfer fluids. Corrosion of stainless steel 316, Hastelloy C276, Inconel 625 and 718 immersed in the three salt mixtures up to 21 days were experimentally investigated at 700 °C under argon atmosphere. The specimens after corrosion tests were characterized by scanning electron microscope, energy dispersive spectroscopy and X-ray diffraction. The results show that SS316 is only compatible with the LiNaK carbonate-salt and the corresponding corrosion rate is lower than 95 μm/year. Both C276 and In625 have relatively good corrosion resistance for the NaKZn chloride-salt and LiF-NaK carbonate-salt, and the corrosion rates are lower than 78 μm/year. The highest corrosion rate over 1700 μm/year is detected for In625 immersed in the LiNaK carbonate-salt. In addition, In718 shows excellent corrosion resistance less than 10 μm/year immersed in all the three salt mixtures. [ABSTRACT FROM AUTHOR]

Highlights • The mathematical model for the coupler curve of the spherical four-bar linkage is established using a spherical coordinate system. • The open path is described using spherical triangles and the influence due to linkage rotation around the three coordinate axes is eliminated. • The geometrical characteristics of the open path are described using wavelet feature parameters. • The theoretical formulas for calculating the installation positions are established. • The non-periodic design requirements of spherical four-bar linkage path synthesis are presented. Abstract A wavelet feature parameters method is proposed for the non-periodic design requirements in the path synthesis of a spherical four-bar linkage mechanism. A mathematical model for the coupler curve of the spherical four-bar linkage is established using a spherical coordinate system. The geometrical characteristics of the open path are described using wavelet feature parameters. Then, a database of wavelet feature parameters is established. Based on the positional relationship of the prescribed curve with the coupler curve generated by the basic dimensional types, the installation positions of the desired linkage can be calculated. Moreover, the open path generation of spherical four-bar linkages can also be performed. Four examples are given. The design results show that the proposed method is effective for the open path generation of spherical four-bar linkages. [ABSTRACT FROM AUTHOR]

Wax gourd (2n = 2 x = 24) is an important vegetable species in Cucurbitaceae . Because it can be stored for a very long period of time, it plays an important role in ensuring the annual supply and regulating off-season supply of the vegetables. However, the availability of genetic information about wax gourd is limited. This study aimed to identify the useful genetic information for wax gourd. The conserved domains of reverse transcriptase (RT) genes of Ty1- copia retrotransposons were isolated from the genome of wax gourd using degenerate oligonucleotide primers. A total of twenty eight RT sequences were obtained, which showed high heterogeneity with the similarity ranging from 47.5% to 94.3%. Sixteen (57.1%) of them were found to be defective, being disrupted by stop codons and/or frameshift mutations. These 28 sequences were divided into five subfamilies. The comparative phylogenetic analysis with other Cucurbitaceae species from GenBank database showed that most retrotransposons derived from the same genus tended to cluster together, although there were a few exceptions. These results indicate that both vertical transmission and horizontal transmission are the sources of Ty1- copia retrotransposons in wax gourd. Fluorescent in situ hybridization (FISH) with Ty1- copia retrotransposon sequences as probes revealed that this kind of retrotransposons had a dispersed genomic organization, physically distributed among all the chromosomes of wax gourd, with clusters in the heterochromatin regions. This is the first report of Ty1- copia retrotransposons in wax gourd, which would be helpful for our understanding about the organization and evolutions of wax gourd genome and also provide valuable information for our utilization of wax gourd retrotransposons. [ABSTRACT FROM AUTHOR]

Superlubricity is an ideal approach to save the service life of medical devices from the tribology point of view. Recently, basil seed gel (BSG) is proved to be a potential candidate with ultralow friction. In this paper, the friction coefficient of BSG is significantly reduced by introducing ethanol. The results indicate that the ethanol molecules enter the BSG network, contributing to transforming the loose structure of polysaccharide nanosheets to the integrated structure. Thus, the mechanical strength of the adsorption layer is improved, which prevents the lubrication film from being destroyed during the sliding process and thus reduces the friction loss. Such macroscopic superlubricity of BSG-ethanol lubricant demonstrates promising potential in biomedical applications such as catheters and gastric tubes. [Display omitted] • Macroscopic superlubricity of basil seed gel is achieved with the help of ethanol. • Ethanol bonds with polysaccharides and contribute to an integrated structure. • The adsorption layer with enhanced mechanical strength prevents friction damage. • A possible superlubricity mechanism model has been proposed. [ABSTRACT FROM AUTHOR]

• There is spatial heterogeneity in carbon storage and sequestration of urban forests. • The carbon storage and sequestration are influenced by a variety of urban factors. • Kriging was used to map the distribution of urban carbon storage and sequestration. To explore available methods for assessing the orientation, magnitude, and role of urban forests in abating climate change, i-Tree Eco and Kriging interpolation were employed to quantify and map the carbon storage and sequestration capability of trees in urban forests. Specifically, urban tree field data were collected from 981 sample plots throughout five types of urban forests in the built-up area of Beijing, China, and used to estimate carbon storage and sequestration within each individual plot and the area as a whole. These data were subsequently subjected to Kriging interpolation to map carbon storage and sequestration within the study area. The results showed that the carbon storage and sequestration patterns in the urban forests in Beijing exhibit noticeable spatial heterogeneity, and that there is a clear, statistically significant distribution of high and low value areas. Furthermore, urban planning, the degree of urbanization, and the urban forest structure effect the carbon spatial distribution. This work provides a reference for prudent planning and construction of urban forests and will aid decision-makers in designing eco-friendly urban environments. [ABSTRACT FROM AUTHOR]

• Zn-GSH significantly enhances survival rates and reduces recovery time from alcohol-induced intoxication in mice, highlighting its potential as a therapeutic agent against alcohol-related damage. • Zn-GSH effectively reduces liver steatosis and preserves the integrity of the intestinal barrier, indicating its dual protective mechanism against alcohol-induced damage to organs. • Zn-GSH was shown to modulate the expression and protein abundance of key intestinal zinc transporters, suggesting a novel approach to restoring zinc homeostasis disrupted by alcohol consumption. • The research provides insight into the mechanistic actions of Zn-GSH, emphasizing its role in maintaining intestinal barrier function and mitigating hepatic inflammation through zinc transporter modulation. Long-term alcohol overconsumption impairs intestinal and hepatic structure and function, along with dysregulation of zinc homeostasis. We previously found that zinc-glutathione (Zn-GSH) complex effectively suppressed alcohol-induced liver injury in mice. This study was undertaken to test the hypothesis that Zn-GSH suppresses alcohol-induced liver injury by modulating intestinal zinc transporters. Mice were subjected to long-term ethanol feeding, as per the NIAAA model, with groups receiving either an ethanol diet alone or an ethanol diet supplemented with Zn-GSH. Treatment groups were carefully monitored for alcohol consumption and subjected to a final binge drinking exposure. The results showed that Zn-GSH increased the survival rate and decreased the recovery time from binge drinking-induced drunkenness. Histopathological analyses demonstrated a reduction in liver steatosis and the preservation of intestinal integrity by Zn-GSH. It was observed that Zn-GSH prevented the reduction of Zn and GSH levels while increasing alcohol dehydrogenase and aldehyde dehydrogenase in both liver and intestine. Importantly, the expression and protein abundance of zinc transporters ZnT-1, ZIP-1, ZIP-4, ZIP-6, and ZIP-14, all of which are critically involved in intestinal zinc transport and homeostasis, were significantly increased or preserved by Zn-GSH in response to alcohol exposure. This study thus highlights the critical role of Zn-GSH in maintaining intestinal zinc homeostasis by modulating zinc transporters, thereby preventing alcohol-induced intestinal and hepatic injury. [Display omitted] [ABSTRACT FROM AUTHOR]

• Corrosion of three molten-salt HTFs were experimentally studied at 700 °C. • Five alloys were tested and characterized by SEM, EDS and XRD. • Corrosion of alloys in the NaKZn chloride-salt with air is not acceptable. • C276 shows lowest corrosion rate of 100 µm/year in the LiNaK carbonate-salt. • In718 is compatible with the LiF-NaK carbonate-salt. The state-of-the-art concentrated solar power tower technology requires novel heat transfer fluids which can operate at a temperature as high as 700 °C. Several molten eutectic salt mixtures are promising heat transfer fluid candidates because they are thermally stable at such high temperature and have good thermophysical properties. However, their corrosion properties to alloys are not investigated thoroughly in the literature. Molten salts usually have high corrosion to alloys, which is a critical issue since the piping and containing materials of the heat transfer fluid in a solar power plant are generally alloys. In this study, the corrosion of three eutectic mixtures including NaCl-KCl-ZnCl 2 , Li 2 CO 3 -Na 2 CO 3 -K 2 CO 3 and LiF-Na 2 CO 3 -K 2 CO 3 to different alloys were experimentally studied at isothermal condition of 700 °C in contact with air. Alloys tested were stainless steel 316 (SS316), Hastelloy C276 (C276), Inconel 625 (In625) and 718 (In718). Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) techniques were employed to characterize the coupon surfaces after corrosion tests. Results show that all the alloys have corrosion rates higher than 450 μm/year immersed in the NaKZn chloride-salt. Therefore, the NaKZn chloride-salt is not applicable as a heat transfer fluid if air cannot be evacuated. C276 immersed in the LiNaK carbonate-salt and In718 immersed in the LiF-NaK carbonate-salt may form protective compact layers on the alloy surfaces to resist corrosion. However, the high cost of lithium salts is another major obstacle to commercialize heat transfer fluids. [ABSTRACT FROM AUTHOR]

In this paper, on the basis of the theory of the Haar wavelet series, the early proposed method, which is used to solve the problem of planar four-bar path synthesis, is extended to motion generation synthesis of a planar four-bar mechanism. By analysing the wavelet coefficients between the rigid-body rotation angle and the connecting rod rotation angle of its corresponding basic dimensional type, the internal relationships are determined. Based on this finding, an output feature parameters database of planar four-bar motion generation including 101,408 sets of the basic dimensional type was established. Using the fuzzy identification method and theoretical formulas to compute the actual size and installing positions parameters of a planar four-bar mechanism, the synthesis of a planar four-bar motion generation mechanism can be achieved using the established numerical atlas, fuzzy identification method and theoretical formulas. [ABSTRACT FROM AUTHOR]

Studies on the kinetic theory of the evaporation of metals in vacuum have already existed, and there have been various applications, such as evaporation filming and powder making in vacuum. However, the vast amount of needed physical parameters has become an obstacle in achieving an accurate measurement, which limits their applications in turn. In addition, there is a lack of experimental research data and simple measurements about the intensive evaporation with the electron beam technology at high temperatures. In this study, a new thermogravimetric analysis (TGA) measuring device was designed for evaporation with the electron beam technology, to track the temperature and mass of the molten pool in real time and obtain abundant and instantaneous experimental data with complete details during the evaporation process. The starting evaporation temperature and the evaporation rate of cobalt, tin, and copper have been measured. In this study, the starting evaporation temperatures of cobalt, tin, and copper are 2173±5 K, 1970±5 K, and 1523±5 K respectively. At 2200–2271 K, the evaporation coefficient of Co is stabilized at around 0.5 with a decreasing tendency; at 1873–2050K, the evaporation coefficient of Cu decreases rapidly from 0.88 to 0.39; at 1979–2038 K, the evaporation coefficient of Sn increases from 0.27 to 0.64. • A new TGA device is designed and used for the measurement of evaporation rate of metals in high temperature range. • Using the curves of the evaporation data of TGA device, the instantaneous evaporation rate of metal is obtained more accurate and reliable by the slope of the curve, rather than the time average evaporation rate. [ABSTRACT FROM AUTHOR]

Heat transfer fluid is a critical component in a concentrating solar power plant. A large quantity of heat transfer fluid is required to transfer heat between the solar collector and the power block, thus it is crucial to select the most appropriate heat transfer fluid in order to maximize the system performance. The present study compared the performances of five molten-salt eutectic mixtures in regarding with the entropy generation rate and the Carnot efficiency of using them as heat transfer fluids. All the five molten-salt eutectic mixtures have thermal stability temperatures above 600 °C. Effects of the tube lengths in the steam generation heat exchanger and the receiver heat exchanger as well as the heat transfer fluid flow rate on both the entropy generation rate and the Carnot cycle efficiency were investigated. The results indicate that the carbonate salts has the worst performances compared to the other eutectic mixtures. The three chloride salts have slightly higher entropy generation rate and 5% higher Carnot efficiency than the Solar Salt. Therefore the three chloride salts are suggested to be used in advanced concentrating solar power tower plants as potential high temperature heat transfer fluids. [ABSTRACT FROM AUTHOR]

With the increasing standardization of food production, the detection of trace food contaminants is becoming extremely crucial. Therefore, it is imperative to carefully select adsorbents with high sensitivity and selectivity for sample pretreatment. Covalent organic frameworks (COFs) possess inherent advantages over other materials, including low density, large surface area, adjustable pore size and structure, as well as customizable features. Recently, there has been a significant advancement in the application of COFs as adsorbents for trace food contaminants. This article reviews the application progress and scenarios of COFs in detecting trace contaminants from different sources. The current focus on detecting various contaminants is summarized and the prospects of COFs in food safety are discussed. Finally, the suggestions for the future detection direction are proposed. This work has significant implications for future advancements in trace detection of food contaminants. COFs have been used in the detection of eight types of food contaminants. [Display omitted] [ABSTRACT FROM AUTHOR]

Amorphous magnesium substituted mesoporous aluminophosphate (AlPO) were prepared, characterized and used as catalysts for the transesterification of diethyl carbonate and dimethyl carbonate in the fixed-bed reactor. The results of FT-IR and XPS confirm the substitution of Mg into the framework of AlPO. Magnesium substituted mesoporous aluminophosphate (MgAPO) have strong basic and weak acid sites according to the results of CO 2 -TPD and NH 3 -TPD. Compared with that of the AlPO catalyst, the pore diameters of the catalysts increased after the introduction of Mg. The activity and stability of the catalysts also improved with the introduction of Mg. The catalytic performance of these catalysts increases in the order of AlPO < Mg 0.1 APO < Mg 0.3 APO < Mg 0.2 APO, which is consistent with the strong basic and weak acid amounts of the catalysts, indicating an acid-base synergistic catalysis in the reaction. The catalyst showed high stability after 960 h of time on stream. As a result, the Mg 0.2 APO presented remarkable activity and durability in the synthesis of ethyl methyl carbonate from dimethyl carbonate and diethyl carbonate in fixed-bed reactor. Image 1 • Magnesium substituted mesoporous aluminophosphate was prepared. • Mg 0.2 APO showed high catalytic performance for the synthesis of ethyl methyl carbonate. • Strong basic and weak acid sites were synergistic catalysis for the transesterification. • The catalyst exhibited high stability after 960 h of time on stream. [ABSTRACT FROM AUTHOR]

Although fresh-cut potato is extremely popular, it is highly prone to browning, severely affecting its quality and shelf life. Nitrogen treatment can inhibit fresh-cut potato browning. Potato browning from the perspective of transcriptome-wide N6-methyladenosine (m6A) methylation has not yet been reported. This study performed transcriptome-wide m6A-sequencing of fresh-cut potato from nitrogen-treated group (1 h N 2) and control group (1 h CK and 0 h CK) to reveal the m6A methylation modification features, and determine the methylation sites of the differentially methylated genes (DMGs). Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated that the DMGs in 1 h CK vs 0 h CK and 1 h N 2 vs 1 h CK were mainly enriched in the isoflavonoid and betalain biosynthesis pathways, respectively. The m6A modifications in potato were mainly enriched around the 3′-untranslated region and stop codons of the coding sequence. The DMG expression was further verified by quantitative real-time polymerase chain reaction (qPCR), while the methylation sites were determined using SELECT qPCR. This study is the first to reveal the transcriptome-wide m6A profile of potato, which may provide new insight into inhibiting fresh-cut potato browning using nitrogen treatment from the perspective of m6A methylation. • The first to reveal the transcriptome-wide m6A profile of potato. • The m6A modifications in potato were mainly enriched around 3′-UTR and stop codons of CDS. • It found difference in methylation at m6A1792 site of tubulin beta-2 chain-like by SELECT qPCR. [ABSTRACT FROM AUTHOR]