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Thermoelectric generators have garnered considerable attention because of their ability to convert thermal energy directly into electricity. In this study, we propose a method to improve the pressure resistance and power generation of thermoelectric modules (TEMs). Silicate inorganic sealant and hollow glass beads, which have good electrical and thermal insulation properties, were used as fillers. A complete hybrid filling process was developed to fill the gaps in the TEM using the filler. Self-made experimental instruments were developed to study the effects of various factors, such as temperature, pressure, and mixing ratio of the filler, affecting the TEM power generation performance. The results showed that the filler effectively improved the compressive strength of the TEM, increasing the pressure resistance of the TEM from 10 MPa to 30 MPa. Moreover, the filled TEM generated 2.17 W at 30 MPa, which was 50.69% higher than that of commercially available pressure-resistant TEM with similar sizes. These results can help in the use of TEM in high-pressure environments. [ABSTRACT FROM AUTHOR]

The Fe–Cu13x molecular sieve catalyst was synthesized by ion exchange method. The product is having various applications, mainly within the food industry, agriculture industry, and also within the pharmaceutical industry. The denitration characteristics and anti-toxicity of Fe–Cu13x catalyst were investigated. Combined with a variety of characterization methods, it was found that the denitration performance of the catalyst was superior, and the denitration rate was more than 99%. In the subsequent anti toxicity test, Fe Cu catalyst showed good sulfur resistance. The NOx conversion rate of the catalyst remained above 90% after 3 h of sulphur resistance, while the no and removal efficiency decreased to 60% after 4 h of sulfur resistance. After the sulfur supply was stopped, the conversion rate did not increase and showed a gradual deactivation state. When the temperature increased to 400 °C, the catalyst could still maintain more than 95% NOx removal rate. [ABSTRACT FROM AUTHOR]

Compressed gas is usually used for the pressure compensation of the deep-sea pressure-maintaining sampler. The pressure and volume of the recovered fluid sample are highly related to the precharged gas. To better understand the behavior of the gas under high pressure, we present a new real gas state equation based on the compression factor Z which was derived from experimental data. Then theoretical calculation method of the pressure and volume of the sample was introduced based on this empirical gas state equation. Finally, the proposed calculation method was well verified by the high-pressure vessel experiment of the sampler under 115 MPa. [ABSTRACT FROM AUTHOR]

Flexible asymmetric rolling process has been conceived to manufacture sheet metal parts with high efficiency. In the asymmetric rolling process, the metal plate is fed into the roll gap at a tilted angle. The nip angles of the top and bottom rolls are not equal, and inconsistent thickness thinning occurs on the two surfaces of the metal plate. It is easy to bend the metal plate during the asymmetric rolling process. Then, desired metal parts with three-dimensional deformation are generated though non-uniformly rolling in the thickness direction. Compared with the 3D rolling technology, shape precision of the metal part with desired configuration is significantly improved. In this paper, the forming sequences of the auxiliary roll height are investigated for forming surface parts. A series of auxiliary roll heights are selected for the metal plate in condition of same roll gap distribution. Numerical simulations and experiments for typically surface parts have been performed. Deformation degree and shape accuracy of the surfaces parts formed in different auxiliary roll heights have been respectively compared and analyzed. Through analyzing deformation degree and shape accuracy of the surfaces parts, it is beneficial for parameters optimization of the flexible asymmetric rolling process. [ABSTRACT FROM AUTHOR]

Gamma dose rates in a uranium site in Guangdong, China were measured based on different functioning areas (mining area, milling area, tailings area and downstream area); four representative soil profiles were measured with HP Ge gamma spectrometry. The gamma dose rates as well as annual effective dose overall exceeded the relevant values reported from other countries. Both the external and the internal hazard index overwhelmingly exceeded the recommended value. Some areas were heavily polluted with technologically elevated concentrations of U and Ra, while others were observed with extremely high background level of natural radioactivity, mainly stemming from granitic lithology. [ABSTRACT FROM AUTHOR]

Eucalyptus has become an important genus in China because it displays adaptability to a wide range of site conditions and produces pulp wood and veneer on short rotations. The aim of this study was to estimate genetic parameters and relationships and consider implications for development of clonal forestry. We assessed growth traits, stem-branch characteristics, crown diameter and height of fresh branch for 20 Eucalyptus hybrid clones in China measured at the age of 44 months. Analysis of variance showed that there were significant differences in growth traits, height of fresh branch and stem straightness among clones. Significant differences in height, volume, crown diameter, height of fresh branch and branch size among replicates were also recorded. Coefficients of variation ranged from 9.84 to 28.54 % for growth traits, 12.03 to 17.25 % for stem-branch characteristics, 18.26 % for crown diameter and 11.73 % for height of fresh branch. Estimates of repeatabilities for height, diameter at breast height over bark, volume, crown diameter, height of fresh branch, stem straightness and branch size at clone mean level were 0.86, 0.80, 0.80, 0.54, 0.85, 0.77 and 0.44 respectively. Diameter at breast height over bark and height had strongly positive phenotypic and genotypic correlations with volume, ranging from 0.96 to 1.00. The positive genotypic and phenotypic correlations between growth traits and other studied traits suggested that fast growing clones always had bigger crown diameter, higher height of fresh branch, straighter stems and relatively smaller branches. [ABSTRACT FROM AUTHOR]

Twenty-four major and trace elements and the mineralogical composition of four sediment cores along the Pearl River and estuary were analyzed using ICP-AES, ICP-MS, and X-ray diffraction (XRD) to evaluate contamination levels. The dominant minerals were quartz, kaolinite, and illite, followed by montmorillonite and feldspars, while small amounts of halite and calcite were also observed in a few samples. Cluster analysis (CA) and principal component analysis (PCA) were performed to identify the element sources. The highest metal concentrations were found at Huangpu, primarily due to wastewater treatment plant discharge and/or the surreptitious dumping of sludge, and these data differed from those of other sources. Excluding the data from Huangpu, the PCA showed that most elements could be considered as lithogenic; few elements are the combination of lithogenic and anthropogenic sources. An antagonistic relationship between the anthropogenic source metals (K, Ba, Zn, Pb, Cd, Ag, Tl, and U) and marine source metals (Na, Mg, Ti, V, and Ca) was observed. The resulting normalized Al enrichment factor ( EF) indicated very high or significant pollution of Cd, Ag, Cu, Zn, Mo, and Pb at Huangpu, which may cause serious environmental effects. Conflicting results between the PCA and EF can be attributed to the background values used, indicating that background values must be selected carefully. [ABSTRACT FROM AUTHOR]

Background: The Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor-E2-related factor 2 (Nrf2)-antioxidant response element pathway serves a major function in endogenous cytoprotection in normal cells. Nrf2 is a transcription factor that mainly regulates the expression of a wide array of genes that produce the antioxidants and other proteins responsible for the detoxification of xenobiotics and reactive oxygen species. Nrf2 mediates the chemoprevention of cancer in normal cells. Results and discussion: Growing body of evidence suggests that Nrf2 is not only involved in the chemoprevention of normal cells but also promotes the growth of cancer cells. However, the mechanism underlying the function of Nrf2 in oncogenesis and tumor protection in cancer cells remains unclear and thus requires further study. Conclusion: This review aims to rationalize the existing functions of Nrf2 in chemoprevention and tumorigenesis, as well as the somatic mutations of Nrf2 and Keap1 in cancer and Nrf2 cross talk with miRNAs. This review also discusses the future challenges in Nrf2 research. [ABSTRACT FROM AUTHOR]

The genes encoding a thermally stable and regio-selective nitrile hydratase (NHase) and an amidase from Comamonas testosteroni 5-MGAM-4D have been cloned and sequenced, and active NHase has been over-produced in Escherichia coli. Maximal activity requires co-expression of a small open reading frame immediately downstream from the NHase beta subunit gene. Compared to the native organism, the E. coli biocatalyst has nearly threefold more NHase activity on a dry cell weight basis, and this activity is significantly more thermally stable. In addition, this biocatalyst converts a wide spectrum of nitrile substrates to the corresponding amides. Such versatility and robustness are desirable attributes of a biocatalyst intended for use in commercial applications. [ABSTRACT FROM AUTHOR]

Due to the high capacity of impurities in its structure, calcite is regarded as one of the most attractive minerals to trap heavy metals (HMs) and radionuclides via substitution during coprecipitation/crystal growth. As a high-reactivity mineral, calcite may release HMs via dissolution. However, the influence of the incorporated HMs and radionuclides in calcite on its dissolution is unclear. Herein, we reported the dissolution behavior of the synthesized calcite incorporated with cadmium (Cd), cobalt (Co), nickel (Ni), zinc (Zn), and uranium (U). Our findings indicated that the HMs and U in calcite could significantly change the dissolution process of calcite. The results demonstrated that the incorporated HMs and U had both inhibiting and enhancing effects on the solubility of calcite, depending on the type of metals and their content. Furthermore, secondary minerals such as smithsonite (ZnCO3), Co-poor aragonite, and U-rich calcite precipitated during dissolution. Thus, the incorporation of metals into calcite can control the behavior of HMs/uranium, calcite, and even carbon dioxide. [ABSTRACT FROM AUTHOR]