Recovery of cobalt sulfate from spent lithium ion batteries by reductive leaching and solvent extraction with Cyanex 272

Cobalt sulfate was recovered from crushed and screened prismatic type spent lithium ion batteries (LIBs) containing 5-20% Co, 5-7% Li, 5-10% Ni, 15% organic chemicals, and 7% plastics together with Cu, Al, Fe, and Mn. Cobalt was reductively leached from the - 16 mesh fraction in 1 h by stirring with 2 M H2SO4 and 6 vol.% H2O2, at 60 °C and 300 rpm using a solid/liquid ratio of 100 g/L to give a cobalt concentration of 28 g/L, corresponding to a leaching efficiency of > 99%. Metal ion impurities such as copper, iron, and aluminium were precipitated as hydroxides from solution by adjusting pH to 6.5. Cobalt was then selectively extracted from the purified aqueous phase by equilibrating with 50% saponified 0.4 M Cyanex 272 at an equilibrium pH ∼ 6. The McCabe-Thiele plot predicted 99.9% cobalt extraction in a 2 stage counter-current operation with A/O ratio of 1/2. Separation factors for the extraction of Co/Li and Co/Ni at pH 6 were close to 750. The stripping of the loaded organic phase with 2 M H2SO4 produced a solution of 96 g/L Co from which pure pigment grade cobalt sulfate could be recovered by evaporation/recrystallisation. Overall, 92% cobalt could be recovered from the spent lithium ion batteries

REVAMPING OF THE NO. 2-3 SLAB CASTER AT POSCO GWANGYANG: DESIGN, START-UP AND INITIAL OPERATION RESULTS

One of the purposes of revamping the No. 2-3 caster was to have annual production capacity of 3.5 milliontonnes per year for automotive application. Under a given caster length of 47m, the basic requirement underthis value is to achieve 2.7 m/min casting speed for 250mm x 1600mm in slab section. In order to ensurestable operation for this high casting speed, many technologies were newly developed and implementedduring the revamping process. The roller geometry was designed to minimize mould level huntingdue to unsteady bulging. The concept of Intensive secondary cooling was applied to shorten crater endposition as well as to decrease corner transverse cracking by applying the concepts of surface structurecontrol [1]. A movable multi-mode electromagnetic system was designed to control mould flow tomeet diverse operation conditions. An Automatic Ar control system was applied at the caster nozzleto minimize nozzle clogging. This caster was started in Nov. 2007 and went up to 2.7m/min incasting speed very quickly. This paper discusses the behaviour of mould level, mould surface flow andsecondary cooling temperature to the directions of slab width and thickness experienced during casting speedincrease and in particular at 2.7m/min maximum casting speed. Initial productivity and slab-quality resultsare also presented

Superior pre-osteoblast cell response of etched ultrafine-grained titanium with a controlled crystallographic orientation

Ultrafine-grained (UFG) Ti for improved mechanical performance as well as its surface modification enhancing biofunctions has attracted much attention in medical industries. Most of the studies on the surface etching of metallic biomaterials have focused on surface topography and wettability but not crystallographic orientation, i.e., texture, which influences the chemical as well as the physical properties. In this paper, the influences of texture and grain size on roughness, wettability, and pre-osteoblast cell response were investigated in vitro after HF etching treatment. The surface characteristics and cell behaviors of ultrafine, fine, and coarse-grained Ti were examined after the HF etching. The surface roughness during the etching treatment was significantly increased as the orientation angle from the basal pole was increased. The cell adhesion tendency of the rough surface was promoted. The UFG Ti substrate exhibited a higher texture energy state, rougher surface, enhanced hydrophilic wettability, and better cell adhesion and proliferation behaviors after etching than those of the coarse- and fine-grained Ti substrates. These results provide a new route for enhancing both mechanical and biological performances using etching after grain refinement of Ti. ? The Author(s) 2017.115Ysciescopu

Anti-Kondo resonance in transport through a quantum wire with a side-coupled quantum dot

An interacting quantum dot side-coupled to a perfect quantum wire is studied. Transport through the quantum wire is investigated by using an exact sum rule and the slave-boson mean field treatment. It is shown that the Kondo effect provides a suppression of the transmission due to the destructive interference of the ballistic channel and the Kondo channel. At finite temperatures, anti-resonance behavior is found as a function of the quantum dot level position, which is interpreted as a crossover from the high temperature Kondo phase to the low temperature charge fluctuation phase.Comment: 4 pages Revtex, 3 eps figure

Vacuum oscillation solution to the solar neutrino problem in standard and non-standard pictures

The neutrino long wavelength (just-so) oscillation is revisited as a solution to the solar neutrino problem. We consider just-so scenario in various cases: in the framework of the solar models with relaxed prediction of the boron neutrino flux, as well as in the presence of the non-standard weak range interactions between neutrino and matter constituents. We show that the fit of the experimental data in the just-so scenario is not very good for any reasonable value of the $^8B$ neutrino flux, but it substantially improves if the non-standard $\tau$-neutrino--electron interaction is included. These new interactions could also remove the conflict of the just-so picture with the shape of the SN 1987A neutrino spectrum. Special attention is devoted to the potential of the future real-time solar neutrino detectors as are Super-Kamiokande, SNO and BOREXINO, which could provide the model independent tests for the just-so scenario. In particular, these imply specific deformation of the original solar neutrino energy spectra, and time variation of the intermediate energy monochromatic neutrino ($^7Be$ and $pep$) signals.Comment: Latex, 14 pages, 9 figures (avalilable by fax or postscript files requested to [email protected]) -- some textual and Latex errors are corrected and few references adde

Оказание медицинской помощи пациентам с акне. Результаты экспертизы качества медицинской помощи

Goal. To obtain information on typical errors in medical aid rendered to acne patients in dermatovenerology dispensaries in St. Petersburg in order to develop measures to improve the quality of medical aid rendered to this group of patients. Materials and methods. The authors conducted a special expert examination of 55 patients with acne who received treatment at St. Petersburg dermatovenerology dispensaries in 2013. The quality of medical aid was assessed using the Automated Expert Examination Technique (hereinafter referred to as AEET). Major results. The percentage of cases when medical aid of due quality was rendered to acne patients was 49%. Treatment and diagnostics errors prevailed in the structure of errors in medical aid. Errors in treatment were mainly a wrong combination of drugs, simultaneous administration of external and systemic antibacterial drugs, delayed comedolytic therapy and pathogenically infeasible therapy. Errors in diagnostics included absence of indications of the form and/or severity of acne. The most important error in the collection of information was absence of gynecology examinations for women to determine whether peroral contraceptives were necessary including in case of the administration of isotretinoin. Conclusion. The similarity of errors in medical aid rendered for acne as well as high percentage of errors relating to medical aid rendered to patients demand the development of consistent measures to improve the quality of medical aid rendered to such patients and repeated expert examination using preliminary (prompt) control of the quality of medical aid.Цель. Получение информации о типичных ошибках оказания медицинской помощи пациентам с акне в кожно-венерологических диспансерах (КВД) Санкт-Петербурга для разработки мер, направленных на улучшение качества медицинской помощи (КМП) данной группе пациентов. Материал и методы. Проведена тематическая экспертиза КМП 55 наблюдений пациентов с акне, которые получали лечение в КВД Санкт-Петербурга в 2013 г. Изучение КМП проводилось с применением Автоматизированной технологии экспертизы КМП. Результаты. Доля случаев оказания медицинской помощи надлежащего качества пациентам с акне составляла 49%. В структуре ошибок оказания медицинской помощи преобладали ошибки лечения и диагноза. Ошибки лечения были представлены преимущественно неверным сочетанием препаратов, наиболее часто одномоментным назначением антибактериальных препаратов для наружного и системного применения, поздним назначением комедолитической терапии, а также применением патогенетически необоснованной терапии. Ошибками постановки диагноза считали отсутствие указаний на форму и/или степень тяжести акне, наиболее важными ошибками сбора информации - отсутствие обследования женщин у гинеколога для решения вопроса о необходимости применения комбинированных оральных контрацептивов, в том числе и при назначении изотретиноина. Заключение. Сходство характера ошибок медицинской помощи при акне, а также их высокий удельный вес при оказании медицинской помощи пациентам требуют разработки системных мероприятий по улучшению КМП этим больным и повторной экспертизы с применением индикаторов промежуточного (оперативного) контроля КМП

Anomaly analysis of Hawking radiation from Kaluza-Klein black hole with squashed horizon

Considering gravitational and gauge anomalies at the horizon, a new method that to derive Hawking radiations from black holes has been developed by Wilczek et al. In this paper, we apply this method to non-rotating and rotating Kaluza-Klein black holes with squashed horizon, respectively. For the rotating case, we found that, after the dimensional reduction, an effective U(1) gauge field is generated by an angular isometry. The results show that the gauge current and energy-momentum tensor fluxes are exactly equivalent to Hawking radiation from the event horizon.Comment: 15 pages, no figures, the improved version, accepted by Eur. Phys. J.

Limits on Fast Radio Burst-like Counterparts to Gamma-Ray Bursts Using CHIME/FRB

Fast radio bursts (FRBs) are a class of highly energetic, mostly extragalactic radio transients lasting for ∼milliseconds. While over 600 FRBs have been published so far, their origins are presently unclear, with some theories for extragalactic FRBs predicting accompanying high-energy emission. In this work, we use the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Fast Radio Burst (CHIME/FRB) Project to explore whether any FRB-like radio emission coincides in space and time with 81 gamma-ray bursts (GRBs) detected between 2018 July 17 and 2019 July 8 by Swift/BAT and Fermi/GBM. We do not find any statistically significant coincident pairs within 3σ of each other's spatial localization regions and within a time difference of up to one week. In addition to searching for spatial matches between known FRBs and known GRBs, we use CHIME/FRB to constrain FRB-like (∼1-10 ms) radio emission before, at the time of, or after the reported high-energy emission at the position of 39 GRBs. For short gamma-ray bursts (SGRBs), we constrain the radio flux in the 400--800 MHz band to be under a few kJy for ∼5.5-12.5 hr post-high-energy burst. We use these limits to constrain models that predict FRB-like prompt radio emission after SGRBs. For long gamma-ray bursts, we constrain the radio flux to be under a few kJy from ∼6 hr pre-high-energy burst to ∼12 hr post-high-energy burst

Opinion dynamics: models, extensions and external effects

Recently, social phenomena have received a lot of attention not only from social scientists, but also from physicists, mathematicians and computer scientists, in the emerging interdisciplinary field of complex system science. Opinion dynamics is one of the processes studied, since opinions are the drivers of human behaviour, and play a crucial role in many global challenges that our complex world and societies are facing: global financial crises, global pandemics, growth of cities, urbanisation and migration patterns, and last but not least important, climate change and environmental sustainability and protection. Opinion formation is a complex process affected by the interplay of different elements, including the individual predisposition, the influence of positive and negative peer interaction (social networks playing a crucial role in this respect), the information each individual is exposed to, and many others. Several models inspired from those in use in physics have been developed to encompass many of these elements, and to allow for the identification of the mechanisms involved in the opinion formation process and the understanding of their role, with the practical aim of simulating opinion formation and spreading under various conditions. These modelling schemes range from binary simple models such as the voter model, to multi-dimensional continuous approaches. Here, we provide a review of recent methods, focusing on models employing both peer interaction and external information, and emphasising the role that less studied mechanisms, such as disagreement, has in driving the opinion dynamics. [...]Comment: 42 pages, 6 figure

Zero-bias conductance peak splitting due to multiband effect in tunneling spectroscopy

We study how the multiplicity of the Fermi surface affects the zero-bias peak in conductance spectra of tunneling spectroscopy. As case studies, we consider models for organic superconductors $\kappa$-(BEDT-TTF)$_2$Cu(NCS)$_2$ and (TMTSF)$_2$ClO$_4$. We find that multiplicity of the Fermi surfaces can lead to a splitting of the zero-bias conductance peak (ZBCP). We propose that the presence/absence of the ZBCP splitting is used as a probe to distinguish the pairing symmetry in $\kappa$-(BEDT-TTF)$_2$Cu(NCS)$_2$.Comment: 7 pages, 7 figure