Mobilization or immobilization? The effect of HDTMA-modified biochar on As mobility and bioavailability in soil.

Biochar plays an essential role in soil remediation, but its effect on the arsenic remediation has been controversial. In this study, hexadecyl trimethyl ammonium bromide (HDTMA-Br) modified or unmodified biochar on As mobility and bioavailability in soil were studied. The sequential extraction experiment showed that As in the original soil mainly existed in the occluded form (78.

Simultaneous immobilization of As and Cd in a mining site soil using HDTMA-modified zeolite.

Arsenic (As) and cadmium (Cd) co-contamination has been a typical problem in Chinese agricultural land adjacent to historical metal mining and smelting activities. Remediation of As and Cd in soil has encountered many difficulties owing to the distinct nature of the two metal(loid)s. In this study, we developed a remediation scheme by adding a hexadecyltrimethylammonium (HDTMA)-modified zeolite to a mining site soil and evaluated the immobilization effect.

Can microplastics pose a threat to ocean carbon sequestration?

Global climate change has attracted worldwide attention. The ocean is the largest active carbon pool on the planet and plays an important role in global climate change. However, marine plastic pollution is getting increasingly serious due to the large consumption and mismanagement of global plastics.

Chemical and microbiological responses of heavy metal contaminated sediment subject to washing using humic substances.

Washing of contaminated soils or sediments using humic substances (HS) extracted either from source-rich materials or compost has been tested effective to remove various heavy metals. Nevertheless, the remaining chemical fractionation of metals and post-washing biological responses were not discussed in previous research. In this study, we used a HS extracted from green waste compost to wash off Cd, As, and Ni from a contaminated sediment, and evaluated the washing effect on sediment microbes by measuring a series of indexes with regard to microbial biomass and enzyme activities.

Humic substances from green waste compost: An effective washing agent for heavy metal (Cd, Ni) removal from contaminated sediments.

In this study, humic substances (HS) selected from 8 composting groups (peanut straw, sesame straw, corn straw and deciduous leaves, with or without grape marc) were used to remove Cd and Ni from artificially contaminated sediments. Sesame straw compost appeared to have the highest removal capacity for heavy metals through a series comparison on Cd removal efficiency, yield of HS and fulvic acids (FA), and seed germination index. The selected sesame HS was further used to wash two contaminated sediments of varying properties (a clay type for sediment 1 and a silty loam for sediment 2).

Association between SATB2 gene polymorphism and cleft palate only risk in eastern Guangdong population and a meta-analysis.

To characterize the associations between the cleft palate (CPO) and single nucleotide polymorphisms (SNPs) of special AT-rich sequence-binding protein 2 (SATB2). We recruited 241 CPO and performed a case-control study with 242 controls. Concurrently, 103 of the patients and their normal parents were recruited to perform a case-parent trio study.