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High-yielding and sustainable production of rice in salt-affected mudflat is restricted by high soil salinity. Although sewage sludge can be used for mudflat amendment especially soil salt reduction, the possibility of potential heavy metal contamination in sludge-amended mudflat especially under paddy cultivation remains unclear, which hinders the further utilization of sewage sludge. In this study, a field experiment was conducted in a newly reclaimed mudflat to assess the sustained effects of one-time sludge input with different addition rates (0, 30, 60, 120, and 180 t ha−1) on soil salinity, rice yield, and potential metal contamination under paddy cultivation. The results indicated that sewage sludge addition (SSA) significantly decreased soil salinity and increased soil fertility. The increasing SSA rates and amending years led to the gradual increase of rice yield in salt-affected mudflat. The maximum increases in rice yield were 125.1%, 124.7%, and 127.9% in 2016, 2017, and 2018, and the average annual increase in rice yield in sludge-treated mudflat was 1.7%. Sludge addition increased metals accumulation in mudflat soil and metals uptake by rice tissues except Cr, Cu, and Pb in rice grain. The maximum increments in metal concentrations in soil and rice plant all occurred at 180 t ha−1 sludge addition rate. However, the metal concentrations in rice grain were below the safety limits even in the treatment with the highest sludge addition rate. Metal concentrations in sludge-treated soil and rice plant showed downward trend during the 3-year trial, and the decreases in total amount of soil metals were mainly concentrated in the first amending year, accounting for more than 50%. In summary, one-time sludge input achieved sustained mudflat amendment and efficient rice production. In addition, controlling the total amount of sludge input realized safe utilization of sewage sludge in salt-affected mudflat under paddy cultivation. [ABSTRACT FROM AUTHOR]

The most important measures for salt-affected mudflat soil reclamation are to reduce salinity and to increase soil organic carbon (OC) content and thus soil fertility. Salinity reduction is often accomplished through costly freshwater irrigation by special engineering measures. Whether fertility enhancement only through one-off application of a great amount of OC can improve soil properties and promote plant growth in salt-affected mudflat soil remains unclear. Therefore, the objective of our indoor pot experiment was to study the effects of OC amendment at 0, 0.5%, 1.0%, 1.5%, and 2.5%, calculated from carbon content, by one-off application of sewage sludge on soil properties, rice yield, and root growth in salt-affected mudflat soil under waterlogged conditions. The results showed that the application of sewage sludge promoted soil fertility by reducing soil pH and increasing content of OC, nitrogen and phosphorus in salt-affected mudflat soil, while soil electric conductivity (EC) increased with increasing sewage sludge (SS) application rates under waterlogged conditions. In this study, the rice growth was not inhibited by the highest EC of 4.43 dS m−1 even at high doses of SS application. The SS application increased yield of rice, promoted root growth, enhanced root activity and root flux activity, and increased the soluble sugar and amino acid content in the bleeding sap of rice plants at the tillering, jointing, and maturity stages. In conclusion, fertility enhancement through organic carbon amendment can "offset" the adverse effects of increased salinity and promote plant growth in salt-affected mudflat soil under waterlogged conditions. [ABSTRACT FROM AUTHOR]

Sewage sludge has been regarded as an economic and efficient soil amendment for mudflat soil amendment despite of the concern of heavy metal contamination. Converting sewage sludge into vermicompost by earthworms may be effective to minimize the risk of heavy metal contamination caused by direct application of sewage sludge in mudflat soil. The objective of this study was to assess the feasibility of vermicompost amendment (VA), and its influence on heavy metal contamination compared with sewage sludge amendment (SSA) in mudflat soil. The results showed that VA improved the physicochemical properties of mudflat soil by decreasing soil bulk density, salinity, and pH, increasing soil organic carbon, nitrogen, and phosphorus contents in the soil. Consequently, the maize biomass and yield were significantly elevated by VA. For heavy metals, VA increased total Cd, Cu, Ni, Pb, and Zn concentrations in mudflat soil, and the maximum increments occurred at 250 t ha-1. Available Cd, Cu, Mn, Ni, and Zn concentrations significantly increased with increasing VA rates. VA increased the accumulation of Cd, Cu, Mn, Ni, Pb, and Zn in maize tissues, especially in root of maize. Compared with SSA under the condition of maintaining equal carbon input, VA allowed heavy metals to accumulate in a more stable binding form in the top 20-cm layer of mudflat soil. Thus, the risk of runoff and leaching of heavy metals and their bioavailability to plants reduced in mudflat soil. As a result, VA decreased the accumulation of heavy metals in maize plant compared with SSA in mudflat soil. In summary, vermicompost can be an effective and safe substitute for sewage sludge for mudflat amendment. [ABSTRACT FROM AUTHOR]

Molybdenum carbide (MoC) catalysts supported on mesoporous carbon (MC) were prepared by the carbothermal hydrogen reduction method. Their properties were characterized by N adsorption, XRD and TEM. The MoC formation procedure was investigated by TPR and XPS. Methyl stearate was employed as a model compound containing oxygen to investigate the hydrodeoxygenation (HDO) activity of MoC/MC catalyst. The results showed MoC was formed on MC at the reduction temperature up to 660 °C. The HDO of methyl stearate on MoC/MC catalyst occurred through two parallel routes to give the main product octadecane and the by-product heptadecane. 10 wt% MoC/MC catalyst exhibited high activity for HDO of methyl stearate with almost 100 % conversion of methyl stearate and high selectivity of 93.6 % toward octadecane, indicating that it is an excellent catalyst to convert vegetable oils into hydrocarbons. [ABSTRACT FROM AUTHOR]

A series of Ag–Pd/C catalysts with different Ag/Pd molar ratios were prepared by impregnation and characterized by N2 adsorption and XPS. The catalytic performance was investigated in the hydrodechlorination of carbon tetrachloride into chloroform. High selectivity toward chloroform, near 100%, was obtained over Ag–Pd/C bi-metal catalysts. A very pronounced surface enrichment with Ag in Ag–Pd/C catalysts determined by XPS may be responsible for the high selectivity of chloroform. It is suggested that hydrodechlorination of carbon tetrachloride into chloroform occurs on the surface of Ag in the Ag–Pd alloy and the role of Pd is to supply H atoms necessary. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma is the most common liver malignancy. Salvage liver transplantation (SLT) is viewed as a feasible cure for recurrence of HCC after resectomy, but the effect is under dispute. A retrospective study examined data at Renji Hospital for 239 transplants from January 2006 to December 2015, including 211 who received primary liver transplantation (PLT) and 28 who underwent SLT. A multivariable cox regression model was employed to pick out relative factors to overall survival (OS) and recurrence free survival (RFS). Propensity score matching (PSM) was used to balance the bias. Both OS and RFS were worse in SLT group than in PLT group, especially for those patients within Milan criteria. Our study demonstrates that SLT bears higher risk of recurrence and death than PLT, indicating that SLT should be given a more careful thought at performance. [ABSTRACT FROM AUTHOR]