scholarly journals Fabricating Na/In/C Composite Anode with Natrophilic Na–In Alloy Enables Superior Na Ion Deposition in the EC/PC Electrolyte

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Hui Wang ◽  
Yan Wu ◽  
Ye Wang ◽  
Tingting Xu ◽  
Dezhi Kong ◽  
...  

AbstractIn conventional ethylene carbonate (EC)/propylene carbonate (PC) electrolyte, sodium metal reacts spontaneously and deleteriously with solvent molecules. This significantly limits the practical feasibility of high-voltage sodium metal batteries based on Na metal chemistry. Herein, we present a sodium metal alloy strategy via introducing NaIn and Na2In phases in a Na/In/C composite, aiming at boosting Na ion deposition stability in the common EC/PC electrolyte. Symmetric cells with Na/In/C electrodes achieve an impressive long-term cycling capability at 1 mA cm−2 (> 870 h) and 5 mA cm−2 (> 560 h), respectively, with a capacity of 1 mAh cm−2. In situ optical microscopy clearly unravels a stable Na ion dynamic deposition process on the Na/In/C composite electrode surface, attributing to a dendrite-free and smooth morphology. Furthermore, theoretical simulations reveal intrinsic mechanism for the reversible Na ion deposition behavior with the composite Na/In/C electrode. Upon pairing with a high-voltage NaVPOF cathode, Na/In/C anode illustrates a better suitability in SMBs. This work promises an alternative alloying strategy for enhancing Na metal interfacial stability in the common EC/PC electrolyte for their future applications.

2018 ◽  
Vol 56 (2A) ◽  
pp. 69-74
Author(s):  
Tran Van Man

The spinel LiNi0.5Mn1.5O4 (LNMO) is considered as an accurate cathode material for high-voltage Li-ions batteries above 4.5 V due to its high energy density, safety and eco-friendly. The electrochemical performance of spinel LNMO depends on the combability between electrode material and electrolyte. In this work, we reported the essential role of solvent compositions–carbonate solvents such as ethylene carbonate (EC), dimethyl carbonate (DMC), ethylene methyl carbonate (EMC)–in 1 M LiPF6 electrolytes on the long-term cycling test. The volumetric ratios in which the solvent compositions were varied were as follows: EC-EMC (7:3), EC-EMC (1:1), EC-DMC (1:1), EC-DMC (1:2). Result of cycling test in the solvent EC-EMC (7:3) leads to a discharge capacity of 140 mAh/g and a retention of 85 % initial capacity after 50 cycles. 


Author(s):  
Christian Kleinert ◽  
Carola Griehl

AbstractThe process of milking microalgae is a promising approach to reduce the downstream costs for the production of valuable substances from microalgae by avoiding the steps of harvest, dewatering, and cell disruption of the common process chain (cultivation, harvesting, dewatering, cell disruption, extraction, purification). The green microalga Botryococcus braunii is particularly suited for this process due to its ability to produce large amounts of long-chain hydrocarbons accumulating in an extracellular matrix. The extracellular location of hydrocarbons is an enormous advantage in comparison with other microalgae that accumulate lipids in intracellular lipid bodies. At present, only a few B. braunii strains (UTEX 572, CCAP 807/2, SAG 807/1, FACHB 357, Bot22, and SCCAP 1761) have been examined for the process of long-term repetitive milking. In order to identify promising candidates for the milking process, twelve different B. braunii strains (SAG 30.81, SAG 807/1, UTEX 572, UTEX 2441, CCAP 807/2, ACOI 58, ACOI 1257, SCCAP K-1489, var. Showa, Bot22, SCCAP K-1761, and CCALA 779) were investigated in terms of growth, lipid accumulation, nutrient uptake, solvent compatibility, and extracellular hydrocarbon extractability. Based on these results, a ranking was defined in view of eligibility for non-destructive hydrocarbon extraction. Results indicate a particular potential for hydrocarbon milking for two of those twelve B. braunii strains. The strain Showa (71 out of 75 ranking points), which has not yet been examined for long-term repetitive milking, and the strain Bot22 (64 out of 75 ranking points) seem to be the most suitable strains for the milking process. They both possess good extractant compatibility including hydrocarbon extractability as well as high biomass and lipid productivity.


2008 ◽  
Vol 5 (1) ◽  
pp. 40 ◽  
Author(s):  
Dawn M. Wellman ◽  
Julia N. Glovack ◽  
Kent Parker ◽  
Emily L. Richards ◽  
Eric M. Pierce

Environmental context. Contamination of surface and subsurface geologic media by heavy metals and radionuclides is a significant problem within the United State Department of Energy complex as a result of past nuclear operations. Numerous phosphate-based remediation strategies have been proposed to introduce hydroxylapatite directly or indirectly (i.e. through in situ precipitation) into subsurface regimes to act as an efficient sorbent for sequestration of metals and radionuclides such as uranium. Results presented here illustrate the importance of variable geochemical conditions on the mechanism of sequestration and long-term retention of uranium in the presence of hydroxylapatite. Abstract. Numerous solid- and aqueous-phase phosphate-based technologies for remediating heavy metals and radionuclides have the common premise of sequestration by hydroxylapatite. Complexation reactions and hydrolysis generally preclude actinides from incorporation into intracrystalline sites; rather, surface sorption and precipitation are significant mechanisms for the sequestration of actinides. The effect of pH, aqueous speciation, and the availability of reactive surface sites on minerals such as hydroxylapatite have a significant impact on the mechanism and degree of sequestration and retention of variably charged contaminants such as uranium. Yet, little attention has been given to the sequestration and retention of uranium by hydroxylapatite under dynamic geochemical conditions that may be encountered during remediation activities. We present the results of an investigation evaluating the removal of uranium by hydroxylapatite in systems near equilibrium with respect to hydroxylapatite, and the effect of dynamic aqueous geochemical conditions, such as those encountered during and subsequent to remediation activities, on the retention of uranium. Results presented here support previous investigations demonstrating the efficiency of hydroxylapatite for sequestration of uranium and illustrate the importance of geochemical conditions, including changes to surface properties and aqueous speciation, on the sequestration and retention of uranium.


Heritage ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 2876-2902
Author(s):  
Clara Moura Soares ◽  
Maria João Neto

Heritage conservation and cultural tourism are central features of academic debates, as this relationship has not been always peaceful. This paper seeks to evaluate the correlation between the extensive conservation and restoration of the wall and castle of the medieval town of Óbidos (1930–1950) and the tourism-oriented projects developed since this period. Due to the criticism of several previous studies, one of the primary aims of this research was to assess whether this Portuguese town constitutes a good example of medieval reconstitution, or if it is a fanciful twentieth-century intervention. Another main goal was to establish our position regarding the challenges inherent to the management of this historic centre, especially those concerning current tourism challenges and the preservation of and regard for historical buildings and monuments. By means of a long-term study based on the common history of art methodology (cross-analysis of bibliography, archival research, in situ observation of the heritage and attendance of festivals and events), we were able to make the following contributions to advance the debate: although the earlier interventions in Óbidos abided by strict criteria which merited international praise, the management model of the town as a tourist destination over the last two decades calls for a revaluation, placing greater importance on history, historic and artistic heritage and the identity of the location.


Author(s):  
W. E. King

A side-entry type, helium-temperature specimen stage that has the capability of in-situ electrical-resistivity measurements has been designed and developed for use in the AEI-EM7 1200-kV electron microscope at Argonne National Laboratory. The electrical-resistivity measurements complement the high-voltage electron microscope (HVEM) to yield a unique opportunity to investigate defect production in metals by electron irradiation over a wide range of defect concentrations.A flow cryostat that uses helium gas as a coolant is employed to attain and maintain any specified temperature between 10 and 300 K. The helium gas coolant eliminates the vibrations that arise from boiling liquid helium and the temperature instabilities due to alternating heat-transfer mechanisms in the two-phase temperature regime (4.215 K). Figure 1 shows a schematic view of the liquid/gaseous helium transfer system. A liquid-gas mixture can be used for fast cooldown. The cold tip of the transfer tube is inserted coincident with the tilt axis of the specimen stage, and the end of the coolant flow tube is positioned without contact within the heat exchanger of the copper specimen block (Fig. 2).


Author(s):  
M.A. O’Keefe ◽  
J. Taylor ◽  
D. Owen ◽  
B. Crowley ◽  
K.H. Westmacott ◽  
...  

Remote on-line electron microscopy is rapidly becoming more available as improvements continue to be developed in the software and hardware of interfaces and networks. Scanning electron microscopes have been driven remotely across both wide and local area networks. Initial implementations with transmission electron microscopes have targeted unique facilities like an advanced analytical electron microscope, a biological 3-D IVEM and a HVEM capable of in situ materials science applications. As implementations of on-line transmission electron microscopy become more widespread, it is essential that suitable standards be developed and followed. Two such standards have been proposed for a high-level protocol language for on-line access, and we have proposed a rational graphical user interface. The user interface we present here is based on experience gained with a full-function materials science application providing users of the National Center for Electron Microscopy with remote on-line access to a 1.5MeV Kratos EM-1500 in situ high-voltage transmission electron microscope via existing wide area networks. We have developed and implemented, and are continuing to refine, a set of tools, protocols, and interfaces to run the Kratos EM-1500 on-line for collaborative research. Computer tools for capturing and manipulating real-time video signals are integrated into a standardized user interface that may be used for remote access to any transmission electron microscope equipped with a suitable control computer.


Author(s):  
Omar Hashim Thanon

Since peaceful coexistence reflects in its various aspects the concept of harmony between the members of the same society with their different national, religious and sectarian affiliations, as well as their attitudes and ideas, what brings together these are the common bonds such as land, interests and common destiny. But this coexistence is exposing for crises and instability and the theft of rights and other that destroy the communities with their different religious, national, sectarian, ethnic aspects, especially if these led to a crisis of fighting or war, which produces only destruction and mass displacement, ttherefore, the process of bridging the gap between the different parts of society in the post-war phase through a set of requirements that serve as the basis for the promotion of peaceful coexistence within the same country to consolidate civil and community peace in order to create a general framework and a coherent basis to reconstruct the community again.      Hence the premise of the research by asking about the extent of the possibility and ability of the community of religious and ethnic diversity, which has been exposed to these crises, which aimed at this diversity, basically to be able to rise and re-integrate within the same country and thus achieve civil and community peace, and Mosul is an example for that, the negative effects of the war and the accomplices of many criminal acts have given rise to hatred and fear for all, leading to the loss of livelihoods, which in the long term may have devastating social and psychological consequences.        To clarify all of this, the title of the first topic was a review of the concept and origin of peaceful coexistence. While the second topic dealt with the requirements of peaceful coexistence and social integration in Mosul, the last topic has identified the most important challenges facing the processes of coexistence and integration in Mosul. All this in order to paint a better future for the conductor at all levels in the near term at the very least to achieve the values of this peaceful coexistence, especially in the post-war period.


Author(s):  
Paolo Giamundo

Background: Minimally-invasive treatments for hemorrhoids should be encouraged as they cause low morbidity, reasonable discomfort and quicker return to work. According to the “vascular theory” hemorrhoidal disease is mainly caused by blood overflow into hemorrhoidal plexus deriving from the superior hemorrhoidal arteries. Introduction: Many different procedures have been described in the literature with the common goal of reducing the blood flow into the hemorrhoidal piles. ‘HeLP’ (Hemorrhoids Laser Procedure) is a novel form of dearterialization to treat patients suffering from symptomatic hemorrhoids. Methods: The procedure consists of the closure of the terminal branches of the superior rectal artery approximately 2-3 cm above the dentate line by means of laser shots originated by a diode laser platform. The arteries, at that level, have variable location and distribution. Therefore, a doppler probe set at the frequency of 20MHz helps identifying the arteries that would be missed otherwise. The laser beam is well tolerated by patients. For this reason, anesthesia is not required in most cases and the procedure allows a quick return to daily activities. In case of concomitant severe mucosal prolapse, the laser treatment can be combined with suture mucopexy. Three to six running sutures allow a complete lifting of hemorrhoidal piles, securing long-term resolution of symptoms. Results and Conclusions: ‘HeLP’ is indicated in patients with symptomatic hemorrhoids where conservative treatment failed and when mucosal prolapse is scarce or not symptomatic. The addition of mucopexy to laser treatment (HeLPexx) contributes to overall resolution of symptoms when mucosal prolapse is an issue, Emborrhoid is another novel, ‘hi-tech’ form of selective dearterialization used in selected case of hemorrhoids where main symptom is bleeding. It is generally used in cases where surgery is contraindicated due to severe concomitant diseases.


Author(s):  
Jill C. Fodstad ◽  
Rebecca Elias ◽  
Shivali Sarawgi

Gender diversity refers to gender expressions and/or gender identity experiences that vary from the common experiences of gender. Gender-diverse people may be gender nonconforming, gender nonbinary, gender fluid, gender exploring, transgender, and so forth. Some gender-diverse individuals experience gender dysphoria and/or gender incongruence and may require gender-affirming supports, including gender-affirming medical interventions. The co-occurrence of autism and gender diversity has been highlighted in a series of studies internationally as well as through rich community expressions. Studies in gender-referred individuals reveal high rates of autism traits as well as high rates of existing autism diagnoses. Studies in autistic populations reveal greater gender diversity characteristics. The long-term course of gender diversity in autistic individuals is poorly understood. Clinical guidelines have been developed for adolescents with the co-occurrence, but much work remains: No gender-related measures have been developed and tested for use in neurodiverse populations, no programs exist to support gender-diverse neurodiverse adults, and little is known about co-occurring mental health profiles, risks, or protective factors for people with the co-occurrence. The inclusion of this chapter on co-occurring autism and gender diversity within a book on “co-occurring psychiatric conditions” is problematic, because gender diversity is not a “psychiatric condition,” but instead a form of human diversity. The diagnosis of Gender Dysphoria is useful only insomuch as it allows individuals to obtain necessary gender-related supports. The authors’ choice to include this chapter in this book reflects a compromise, motivated by the need for educating both autism and gender specialists in this common co-occurrence.


Author(s):  
Yue Ma ◽  
Qifang Sun ◽  
Zhenyu Wang ◽  
Su Wang ◽  
Ying Zhou ◽  
...  

Ni-rich layered oxide LiNi0.8Co0.15Al0.05O2 (NCA) is one of the most promising cathode candidates for higher energy density lithium batteries. However, the extensive application of NCA is hindered due to the...


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