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Magneli phase titanium sub-oxide conductive ceramic TiO was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/TiO composites were prepared by the impregnation-reduction method. The electrochemical stability of TiO was investigated and the results show almost no change in the redox region after oxidation for 20 h at 1.2 V (vs NHE) in 0.5 mol/L HSO aqueous solution. The catalytic activity and stability of the Pt/TiO toward the oxygen reduction reaction (ORR) in 0.5 mol/L HSO solution were investigated through the accelerated aging tests (AAT), and the morphology of the catalysts before and after the AAT was observed by transmission electron microscopy. At the potential of 0.55 V (vs SCE), the specific kinetic current density of the ORR on the Pt/TiO is about 1.5 times that of the Pt/C. The LSV curves for the Pt/C shift negatively obviously with the half-wave potential shifting about 0.02 V after 8000 cycles AAT, while no obvious change takes place for the LSV curves for the Pt/TiO. The Pt particles supported on the carbon aggregate obviously, while the morphology of the Pt supported on TiO remains almost unchanged, which contributes to the electrochemical surface area loss of Pt/C being about 2 times that of the Pt/TiO. The superior catalytic stability of Pt/TiO toward the ORR could be attributed to the excellent stability of the TiO and the electronic interaction between the metals and the support. [ABSTRACT FROM AUTHOR]

Food security is the top priority of a country. As an important granary in China, the northeast black land is a "ballast" to ensure national food security. However, the long-term and high-intensity application of herbicides in black land farmland has led to the accumulation and migration of herbicides in the soil, which affects soil quality, crop yield, and quality and hinders sustainable agricultural development in the black soil. To solve the problem of herbicide residues in black land farmland, it is necessary to control the application of herbicides from the source, as well as to elucidate the current situation, spatial and temporal evolution, and driving factors of herbicide residues, in order to achieve scientific prevention and control and precise policy implementation. The main contents of this study were as follows:1systematically summarize the application status and problems of herbicides in the farmland of black soil in China, suggesting that there are currently problems such as irregular application and insufficient product innovation of herbicides in the farmland of black soil; 2 comprehensively analyze the current status of herbicide residues, identify the deficiencies in recent studies on herbicide residue characteristics, spatial distribution, and pollution diagnosis in the farmland of black soil, and clarify the gaps in the research on the residue characteristics of herbicides in the farmland of black soil; and 3 propose the research prospect and key orientation for the herbicide residue diagnosis and risk management in the farmland of the black soil region of China. The results of this study can provide science and technology support for guaranteeing soil health, food security, and ecosystem security of black land farmland in China.

The Yangtze River Economic Belt is one of the major strategic development regions in China. It is of great significance to clarify the characteristics and sources of heavy metal pollution in farmland soil of the Yangtze River Economic Belt for the prevention and control of heavy metal pollution and to ensure safe agricultural production. After collecting extensive literature data, we analyzed the pollution characteristics, environmental risk, and potential sources of heavy metals (Cd, Cr, Hg, As, Pb, Cu, Zn, and Ni) in farmland soil of the Yangtze River Economic Belt through the integrated use of spatial and geo-accumulation index analyses. The results showed that:① the proportion of soil samples exceeding the risk screening values for soil contamination of agricultural land of Cd, Cu, Pb, Hg, Zn, and As were 39.8%, 18.5%, 8.3%, 6.9%, 6.9%, and 6.4%, respectively. Compared with the risk standard, soil Cd had the highest rate of exceeding the standard. ② The contents of Cr, Cu, Zn, and Ni in the upper reaches were higher than those in the middle and lower reaches, and the contents of Cd, As, and Pb in the middle reaches were higher than those in the upper and lower reaches. ③ The results of the geo-accumulation index analysis showed that the contamination degree of the eight heavy metals decreased in the order of Cd(0.42)>Hg(-0.28)>Pb(-0.32)>Zn(-0.39)>Cu(-0.42)>Cr(-0.7)>As(-0.81)>Ni(-0.73), where the accumulation risk of soil Cd and Hg was relatively higher. ④ Higher environmental background and mining activities were the main factors affecting the accumulation of heavy metals in soils in the upper and middle reaches. By contrast, rapid urbanization, industrial production, and intensive agricultural activities were the main factors affecting the heavy metal accumulation in soils in the middle and lower reaches. In view of the current status and control needs of heavy metal pollution in the Yangtze River Economic Belt, it is recommended to strengthen source prevention and control and to also carry out hierarchical control and regional classification management of heavy metal pollution in farmland soils according to the degree of heavy metal pollution, geological background, and quality of agricultural products. The ultimate objective of this research was to archive the farmland soil environmental quality safety and agricultural green sustainable production in the Yangtze River Economic Belt.

Hydrocalumite (Ca-Al-LDHs) is a new type of layered composite metal hydroxide that has a large specific surface area, high anion exchange performance, and high stability. This study focuses on the application of hydrocalumite to remediate different Cd-contaminated farmland soils. These were collected from the Lanping County in the Yunnan Province (highly polluted), Kunshan City in the Jiangsu Province (medium polluted), and Nanjing City in the Jiangsu Province (lowly polluted). Changes in the available Cd, Pb, Zn, and the morphological transformations of these heavy metals in the three soils were investigated through a passivation experiment; moreover, the immobilization mechanism of hydrocalumite was explored by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The results showed that hydrocalumite could increase the soil pH and reduce the content of available Cd, Pb, and Zn:the maximum reduction in the available Cd reached 97.7%, 96.3%, and 91.8% in each of the three polluted soils, respectively. The easily exchangeable heavy metals were converted into carbonates, as well as into Fe-Mn oxide organic and residual forms following the addition of hydrocalumite:the passivation effect was more evident in the highly Cd-polluted soil than in the low and medium Cd-polluted soils. Since hydrocalumite possess several adsorption sites, the presence of carbonate impurities and reactive groups (e.g., hydroxyl and carboxyl groups) easily coordinated with Cd, Pb, and Zn can lead to a considerable reduction of heavy metal availability in the soils. Therefore, we conclude that hydrocalumite can be effectively applied to the remediation of farmland soils characterized by different Cd pollution levels.

Objective: To investigate the gene mutation types and spectrum of α, β-thalassemia in Fuzhou area of China., Methods: Thalassemia gene screening was performed in the women receiving physical, prenatal, and pre-pregnancy examination, and the patients with suspected thalassemia in our hospital from July 2013 to March 2018.Genotypes of thalassem were detected by Gap-PCR and RDB-PCR., Results: 1042 were positive among 2074 suspected cases with a positive rate of 50.24%; 618 cases were confirmed to be α-thalassemia and with a positive rate of 29.8%; 409 cases were confirmed to be β-thalassemia with a positive rate of 19.72%. 15 cases were confirmed to be α-β complex thalassemia with a positive rate of 0.72%. the -- SEA /αα(76.54%) was the most common genotype among α-thalassemia, -α 3.7 /αα(10.03%) and -α 4.2 /αα(2.91%) in hot pursuit. In addition, IVS-II-55 (T->G) and IVS-II-119 (-G, +CTCGGCCC) were newly found alpha mutations; the IVS-2-654 (C→T) (40.83%) was the most common genotype among β-thalassemia, CD41-42 (-TCTT) (35.94%) and CD17 (A→T) (9.78%) in hot pursuit., Conclusion: The genotype of thalassemia in Fuzhou area is highly heterogenic, -- SEA /αα is the most common genotype among α-thalassemia, IVS-2-654 (C→T) is the most common genotype among β-thalassemia, Meanwhile, two α-mutation sites are found in this study which were not reported in the Database of Human Hemoglobin Variants and Thalassemias.