Study on the Behavior of Electrochemical Extraction of Cobalt from Spent Lithium Cobalt Oxide Cathode Materials

The molten salt electrochemical method was used to reduce the Co in spent LiCoO2. The reduction mechanism of Co (III) in LiCoO2 was analyzed by cyclic voltammetry, square wave voltammetry, and open circuit potential. The reduction process of Co (III) on Fe electrode was studied in NaCl-CaCl2-LiCoO2 molten salt system at 750 °C. The results show that the reduction process of Co (III) is a two-step reduction: Co (III) → Co (II) → Co (0) and they are all quasi-reversible processes controlled by diffusion. Phase analysis (XRD) shows that Li+ and Cl2− in the molten salt form LiCl electrolysis experiments with different voltages were carried out, which proved the stepwise reduction of Co in LiCoO2.

Aqueous Electrodeposition of SmCo Alloys: II. Direct Current Studies

Previously, we reported the aqueous electrodeposition of rare earth - iron group alloys. A key factor was the complexation of the metal ions with various coordination compounds (e.g., aminoacetic acids), without which only the ferrous metal and rare earth hydroxides/oxides are deposited. In this work, samarium cobalt (SmCo) alloys were synthesized using direct current (DC) aqueous electrodeposition. The basic electrolyte solution consisted of 1 M samarium sulfamate, 0.05 M cobalt sulfate, and 0.15 M glycine, resulting in deposits containing >30 at% Sm at 60°C with current density of 500 mA/cm2. Supporting electrolytes (i.e., ammonium salts) decreased the Sm content in the deposit. Crystallinity of deposited films altered from nanocrystalline to amorphous as the Sm content increased. Deposits with high Sm content (32 at%) became isotropic with reduction in magnetic saturation (Ms) and coercivity (Hc). A deposition mechanism involving stepwise reduction of the complexed Sm-Co ions by depositing hydrogen atoms was proposed.

Pancreatic enzyme autodigestion of an unresectable retroperitoneal liposarcoma

This is a case of a 71-year-old man who had multiple synchronous retroperitoneal liposarcoma (LPS) foci composed of both well-differentiated and dedifferentiated histologies. In addressing this, the patient underwent a margin negative resection of a 11.8×8.8 cm right-sided dedifferentiated LPS requiring pancreaticoduodenectomy; however, a 13.1×7.2 cm left-sided well-differentiated LPS (WDLPS) was not resected due to its involvement of the proximal mesenteric vessels. The patient’s postoperative course was complicated by grade B postoperative pancreatic fistula involving the anatomical territory of the residual WDLPS. Over the next 12 months, serial CT scans demonstrated a stepwise reduction in size of the WDLPS until it completely regressed. The authors hypothesise that enzymes shed from the pancreatic fistula initiated the autodigestion and subsequent necrosis of the WDLPS with associated tumour regression.

Locus Coeruleus Pathology Indicates a Continuum of Lewy Body Dementia

Background: Lewy body dementia (LBD) has two main phenotypes of LBD, Parkinson’s disease dementia (PDD) and dementia with Lewy bodies (DLB), separated by the ‘one-year-rule’. They also show different symptom profiles: core DLB features include fluctuating cognition, REM-sleep behaviur disorder, and visual hallucinations. These symptoms are sometimes present in PDD, representing an intermediate ‘PDD-DLB’ phenotype. Objective: DLB-like features may reflect deficits in the functions of the noradrenergic nucleus locus coeruleus (LC). Therefore, we compared the LC in the LBD phenotypes, PD, and controls. Methods: 38 PD, 56 PDD, 22 DLB, and 11 age-matched control cases from the Parkinson’s UK tissue bank were included. LC tissue sections were immunostained for tyrosine-hydroxylase (TH), α-synuclein, tau, and amyloid-β. TH-neurons were quantified and pathologic burden calculated by %-coverage method. Results: The LC shows a stepwise reduction in neuron count from controls, PD, PDD, to DLB. PDD-DLB cases showed an intermediate clinical phenotype that was reflected pathologically. Cell counts were significantly reduced in DLB compared to PDD after correction for demographic factors. LC degeneration contributed significantly to the onset of all DLB symptoms. While α-synuclein was not significantly different between PDD and DLB cases, DLB exhibited significantly less tau pathology. Conclusion: DLB and DLB-like symptoms represent noradrenergic deficits resulting from neuronal loss in the LC. PDD and DLB are likely to represent a clinical continuum based on the presence or absence of DLB-like symptoms mirrored by a pathological continuum in the LC.

Highly Efficient Debromination of 4,4ʹ-dibrominated Diphenyl Ether by Organic-palygorskite Supported Pd/Fe Nanoparticles

Organic-palygorskite (OP) supported Pd/Fe nanoparticles composite (OP-Pd/Fe) was prepared by stepwise reduction method. The removal capacity of 4,4ʹ-dibrominated diphenyl ether (BDE15) by OP-Pd/Fe was compared with other various materials. For better understanding the possible mechanism, the synthesized and reacted OP-Pd/Fe materials were characterized by TEM, SEM, XRD, and XPS, respectively. The effects of major influencing parameters on the degradation of BDE15 were also studied. Benefit from the synergistic effect of the carrier and bimetallic nanoparticles, BDE15 could be completely debrominated into diphenyl ether (DE) under suitable conditions. A two-stage adsorption/debromination removal mechanism was proposed. The degradation of BDE15 with OP-Pd/Fe was mainly stepwise debromination reaction, and hydrogen transfer mode was assumed as the dominated debromination mechanism. The removal process fitted well to the pseudo first-order kinetic equation. The observed rate constants increased with increasing Pd loading and OP-Pd/Fe dosage, while decreased with increasing initial BDE15 concentration, the tetrahydrofuran/water ratio, and the initial pH of the solution. The work provides a new approach for the treatment of PBDEs pollution.

Some Aspects of the Thermochemical Route for the Valorization of Plastic Wastes, Part I: Reduction of Iron Oxides by Polyvinyl Chloride (PVC)

The mass production of synthetic plastics began in the last century and today they have become one of the most abundant man-made materials. The disposal or the beneficiation of end-of-life plastics represent a great challenge for society especially in the case of polyvinyl chloride (PVC). This study is focused on the use of PVC waste as a useful agent for the direct reduction of hematite (Fe2O3) after a thermal treatment at 300 °C for removing the chlorine contained in PVC. Thermal reduction tests were conducted from 600 °C to 1100 °C with (Fe2O3 + PVC + clay) pellet mixtures in which clay was used as plasticizing and binder agent of the pellets. The starting samples and treatment residues were analyzed by scanning electron microscopy through energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD) to monitor the chemical behavior and reactivity of the pellet constituents during their thermal treatment. The stepwise reduction of hematite up to metallic iron was achieved at temperatures approaching 1000 °C, confirming the capability of using PVC waste for the direct reduction of iron oxides.

Zygotic contractility awakening during mouse preimplantation development

Actomyosin contractility is a major engine of preimplantation morphogenesis, which starts at the 8-cell stage during mouse embryonic development. Contractility becomes first visible with the appearance of periodic cortical waves of contraction (PeCoWaCo), which travel around blastomeres in an oscillatory fashion. How contractility of the mouse embryo becomes active remains unknown. We have taken advantage of PeCoWaCo to study the awakening of contractility during preimplantation development. We find that PeCoWaCo become detectable in most embryos only after the 2nd cleavage and gradually increase their oscillation frequency with each successive cleavage. To test the influence of cell size reduction during cleavage divisions, we use cell fusion and fragmentation to manipulate cell size across a 20-60 μm range. We find that the stepwise reduction in cell size caused by cleavage divisions does not explain the presence of PeCoWaCo or their accelerating rhythm. Instead, we discover that blastomeres gradually decrease their surface tensions until the 8-cell stage and that artificially softening cells enhances PeCoWaCo prematurely. Therefore, during cleavage stages, cortical softening awakens zygotic contractility before preimplantation morphogenesis.

Rice by-Products Reduce Seed and Seedlings Survival of Echinochloa crus-galli, Leptochloa chinensis and Fymbristylis miliacea

Extracting allelochemicals from rice (Oryza sativa) straw and use for weed management is more sustainable than burning and reduces herbicide dependence. Water soluble compounds were extracted from shoots and roots of OM 5930, generating both a crystallized by-product and liquid extract. Crystallized product was applied to soil with pre-germinated barnyardgrass (Echinochloa crus-galli L. Beauv), red sprangletop (Leptochloa chinensis L. Nees), and grass-like fimbry (Fimbristylis miliacea L. Vahl) seeds. As little as 9.4 g per pot (1 ton ha−1 biomass) reduced survival of all species, with the order of sensitivity barnyardgrass (BG) < red sprangletop (RS) < grasslike-fimbry (GF). Increased rates or time of exposure (3 to 42 days after treatment; DAT) resulted in a stepwise reduction in seed survival. Using liquid extract, 5.33 g pot−1 (3 tons ha−1 biomass) reduced BG survival by 49.8%, while 2.67 g pot−1 reduced survival of RS and GF by 49.7 and 54.3%, respectively at 42 DAT. A rate of 8 g pot−1 reduced survival of BG seedlings by 78.3% but was lethal to RS and GF seedlings. The most abundant allelochemicals present were ergosterol peroxide, p-coumaric acid, and salicylic acid. OM 5930 rice is a promising variety for extraction of allelopathic compounds and application for extended herbicidal activity.