Deep removal of trace arsenic from acidic SbCl3 solution by in-situ galvanically coupled Cu2Sb/Cu particles.

Arsenic is a harmful associated element in antimony ore, which might bring out the risk of leakage during complex industrial production of high-purity antimony. Herein, we reported a novel and efficient way to remove the trace arsenic impurity from acidic SbCl3 solution by utilizing copper-system bimetallic particles. Specifically, galvanically coupled Cu2Sb/Cu was in-situ synthesized by introducing precursor copper powder to the specific SbCl3 solution. DFT studies revealed that Sb(III) was easily reduced by Cu to form Cu2Sb due to the strong adsorption of Sb(III) on Cu (111) crystal plane. The Cu2Sb/Cu coupling exhibited excellent activity for As(III) reduction, over 99.4% arsenic were removed under optimal conditions and residual arsenic concentration dropped to only 2.7 mg L-1. Crucially, Sb(III) concentration changes could be neglected. Besides, the dearsenization residues were extensively characterized to analyze the evolvement and cause in the reaction process. The results confirmed that the arsenic removal mechanisms by Cu2Sb/Cu particles were multi-affected, including adsorption, displacement, and precipitation. And the strong electrostatic attraction of AsO+ under high HCl conditions was identified as a key step to achieving dearsenization. This research will provide a theoretical guidance for the green synthesis of high-purity antimony and related products.

Activating mGlu3 Metabotropic Glutamate Receptors Rescues Schizophrenia-like Cognitive Deficits Through Metaplastic Adaptations Within the Hippocampus.

BACKGROUND: Polymorphisms in GRM3, the gene encoding the mGlu3 metabotropic glutamate receptor, are associated with impaired cognition and neuropsychiatric disorders such as schizophrenia. Limited availability of selective genetic and molecular tools has hindered progress in developing a clear understanding of the mechanisms through which mGlu3 receptors regulate synaptic plasticity and cognition. METHODS: We examined associative learning in mice with trace fear conditioning, a hippocampal-dependent learning task disrupted in patients with schizophrenia. Underlying cellular mechanisms were assessed using ex vivo hippocampal slice preparations with selective pharmacological tools and selective genetic deletion of mGlu3 receptor expression in specific neuronal subpopulations. RESULTS: mGlu3 receptor activation enhanced trace fear conditioning and reversed deficits induced by subchronic phencyclidine. Mechanistic studies revealed that mGlu3 receptor activation induced metaplastic changes, biasing afferent stimulation to induce long-term potentiation through an mGlu5 receptor-dependent, endocannabinoid-mediated, disinhibitory mechanism. Selective genetic deletion of either mGlu3 or mGlu5 from hippocampal pyramidal cells eliminated effects of mGlu3 activation, revealing a novel mechanism by which mGlu3 and mGlu5 interact to enhance cognitive function. CONCLUSIONS: These data demonstrate that activation of mGlu3 receptors in hippocampal pyramidal cells enhances hippocampal-dependent cognition in control and impaired mice by inducing a novel form of metaplasticity to regulate circuit function, providing a clear mechanism through which genetic variation in GRM3 can contribute to cognitive deficits. Developing approaches to positively modulate mGlu3 receptor function represents an encouraging new avenue for treating cognitive disruption in schizophrenia and other psychiatric diseases.

Preparation of Ultrathin, Robust Nanohybrid Capsules through a "Beyond Biomineralization" Method.

Herein, a facile and generic method is developed to prepare ultrathin, robust nanohybrid capsules by manipulating the dynamic structure of supramolecular nanocoatings on CaCO3 sacrificial templates by incorporating a multivalent-anion substitution process into biomineralization. Above the biomineralization level, multivalent anions, for example, phosphate, sulfate, or citrate, are used to initiate the assembly of polyamine into continuous (nonsegregated) polyamine-anion supramolecular nanocoatings on CaCO3 sacrificial templates. When contacting with the sodium silicate solution, the multivalent anions in the supramolecular nanocoatings are substituted by silicate because of the difference in dissociation behavior, facilitating the structure-reconstruction of supramolecular nanocoatings. At the biomineralization level, the substituted silicate can not only bind to the polyamine through electrostatic and hydrogen bonding interactions but also undergo silicification to generate an interpenetrating silica framework. After dissolution of CaCO3, polyamine-silica nanohybrid capsules bearing an ultrathin wall of ∼10-17 nm in thickness are formed, which exhibit a super-high mechanical strength of ∼2337 MPa in elasticity modulus. The capsules are then utilized for bioreactor construction by encapsulating glucose oxidase. The ultrathin capsule wall facilitates the diffusion of substrates/products and elevates the conversion efficiency, whereas the high mechanical strength ensures the structural integrity of the capsules during multiple-cycle reactions. This method can also be applied for the preparation of ultrathin films on planar substrates, which would open a feasible way to prepare nanohybrid materials with different compositions and shapes.

An Efficient, Recyclable, and Stable Immobilized Biocatalyst Based on Bioinspired Microcapsules-in-Hydrogel Scaffolds.

Design and preparation of high-performance immobilized biocatalysts with exquisite structures and elucidation of their profound structure-performance relationship are highly desired for green and sustainable biotransformation processes. Learning from nature has been recognized as a shortcut to achieve such an impressive goal. Loose connective tissue, which is composed of hierarchically organized cells by extracellular matrix (ECM) and is recognized as an efficient catalytic system to ensure the ordered proceeding of metabolism, may offer an ideal prototype for preparing immobilized biocatalysts with high catalytic activity, recyclability, and stability. Inspired by the hierarchical structure of loose connective tissue, we prepared an immobilized biocatalyst enabled by microcapsules-in-hydrogel (MCH) scaffolds via biomimetic mineralization in agarose hydrogel. In brief, the in situ synthesized hybrid microcapsules encapsulated with glucose oxidase (GOD) are hierarchically organized by the fibrous framework of agarose hydrogel, where the fibers are intercalated into the capsule wall. The as-prepared immobilized biocatalyst shows structure-dependent catalytic performance. The porous hydrogel permits free diffusion of glucose molecules (diffusion coefficient: ∼6 × 10(-6) cm(2) s(-1), close to that in water) and retains the enzyme activity as much as possible after immobilization (initial reaction rate: 1.5 × 10(-2) mM min(-1)). The monolithic macroscale of agarose hydrogel facilitates the easy recycling of the immobilized biocatalyst (only by using tweezers), which contributes to the nonactivity decline during the recycling test. The fiber-intercalating structure elevates the mechanical stability of the in situ synthesized hybrid microcapsules, which inhibits the leaching and enhances the stability of the encapsulated GOD, achieving immobilization efficiency of ∼95%. This study will, therefore, provide a generic method for the hierarchical organization of (bio)active materials and the rational design of novel (bio)catalysts.

[Primary study of arginine as feed attractants on Whitmania pigra].

The effects of the feed attractants on Whitmania pigra were studied. The average weight of Wh. pigra were 5.0 g. Arginine was selected as feed attractants, xanthan gum was selected as feed substrate. The times of Wh. pigra going into the inducing room were recorded. The water temperature was 22-25 degrees C during the whole experiment. Arginine that had better inducing effect was chosen to carry on in the gradient experiment. The results showed that the best inducing effect was found when the added amount of arginine was 0.3%, which was close to the arginine content of the natural body fluid of Wh. Pigra and Bellamya purificata, 2.97 mg x g(-1).