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1.
Nanoscale ; 16(16): 7937-7950, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38545684

ABSTRACT

Li-air battery (LAB) technology is making continuous progress toward its theoretical capacity, which is comparable to gasoline. However, the sluggish reaction at the cathode is still a challenge. We propose a simple strategy to optimize the surface eg occupancy by adjusting the stoichiometric ratios of transition metal-based spinel structures through a controlled hydrothermal synthesis. Three distinct stoichiometries of Ni-Co oxides were used to demonstrate the direct correlation between stoichiometry and catalytic performance. The groundsel flower-like structure having a 1 : 1.4 Ni : Co atomic ratio with high surface area, high defect density, and an abundance of Ni3+ at the surface with semi-filled eg orbitals was found to benefit the structure promoting high catalytic activities in aqueous and aprotic media. The assembled LAB cells employing this cathode demonstrate an exceptional lifespan, operating for 3460 hours and completing 173 cycles while achieving the highest discharge capacity of 13 759 mA h g-1 and low charging overpotentials. The key to this prolonged performance lies in the full reversibility of the cell, attributed to its excellent OER performance. A well-surface adsorbed, amorphous LiO2/Li2O2 discharge product is found to possess high diffusivity and ease of decomposition, contributing significantly to the enhanced longevity of the cell.

2.
Adv Mater ; : e2313273, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38533901

ABSTRACT

The rapid growth of electric vehicle use is expected to cause a significant environmental problem in the next few years due to the large number of spent lithium-ion batteries (LIBs). Recycling spent LIBs will not only alleviate the environmental problems but also address the challenge of limited natural resources shortages. While several hydro- and pyrometallurgical processes are developed for recycling different components of spent batteries, direct regeneration presents clear environmental, and economic advantages. The principle of the direct regeneration approach is restoring the electrochemical performance by healing the defective structure of the spent materials. Thus, the development of direct regeneration technology largely depends on the formation mechanism of defects in spent LIBs. This review systematically details the degradation mechanisms and types of defects found in diverse cathode materials, graphite anodes, and current collectors during the battery's lifecycle. Building on this understanding, principles and methodologies for directly rejuvenating materials within spent LIBs are outlined. Also the main challenges and solutions for the large-scale direct regeneration of spent LIBs are proposed. Furthermore, this review aims to pave the way for the direct regeneration of materials in discarded lithium-ion batteries by offering a theoretical foundation and practical guidance.

3.
ACS Appl Mater Interfaces ; 16(5): 5847-5856, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38284621

ABSTRACT

The rational design of cost-effective and efficient electrocatalysts for electrochemical water splitting is essential for green hydrogen production. Utilizing nanocatalysts with abundant active sites, high surface area, and deliberate stacking faults is a promising approach for enhancing catalytic efficiency. In this study, we report a simple strategy to synthesize a highly efficient electrocatalyst for the hydrogen evolution reaction (HER) using carbonized luffa cylindrica as a conductive N-doped carbon skeleton decorated with Ag nanorings that are activated by introducing stacking faults. The introduction of stacking faults and the resulting tensile strain into the Ag nanorings results in a significant decrease in the HER overpotential, enabling the use of Ag as an efficient HER electrocatalyst. Our findings demonstrate that manipulating the crystal properties of electrocatalysts, even for materials with intrinsically poor catalytic activity such as Ag, can result in highly efficient catalysts. Further, applying a conductive carbon backbone can lower the quantities of metal needed without compromising the HER activity. This approach opens up new avenues for designing high-performance electrocatalysts with very low metallic content, which could significantly impact the development of sustainable and cost-effective electrochemical water-splitting systems.

4.
Arq. bras. oftalmol ; 86(3): 223-231, May 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1439379

ABSTRACT

ABSTRACT Purpose: To compare viscotrabeculotomy with anterior chamber irrigation to Ahmed glaucoma valve implantation for secondary glaucoma following silicone oil removal. Methods: A prospective study was conducted on 43 vitrectomized pseudophakic eyes with persistent glaucoma after silicone oil removal. Patients were randomized to either viscotrabeculotomy with anterior chamber irrigation or Ahmed glaucoma valve implantation. All patients were examined on day 1, week 1, and months 1, 3, 6, 9, 12, 18, and 24 postoperatively. Postoperative complications were noted. Success was defined as an intraocular pressure between 6 and 20 mmHg and with an intraocular pressure reduction of >30% compared with the preoperative intraocular pressure. Results: There were 22 eyes in the viscotrabeculotomy with anterior chamber irrigation and 21 eyes in the Ahmed glaucoma valve implantation group. The mean preoperative and postoperative intraocular pressure in the viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation groups were 35.5 ± 2.6 mmHg and 35.5 ± 2.4 mmHg and 16.9 ± 0.7 mmHg and 17.9 ± 0.9 mmHg respectively (p˂0.0001). There was a statistically significant intraocular pressure reduction at all follow-up time points compared to preoperative values (p˂0.0001) in both groups. The unqualified success rate in the viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation groups were 72.73% and 61.9%, respectively. A minimal self-limited hyphema was the most common complication. Conclusions: Both viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation are effective in lowering the intraocular pressure in glaucoma after silicone oil removal with viscotrabeculotomy with anterior chamber irrigation providing greater reduction, higher success rates, and minimal complications.


RESUMO Objetivo: Comparar a viscotrabeculotomia com irrigação da câmara anterior com o implante de válvula de glaucoma de Ahmed para glaucoma secundário após remoção de óleo de silicone. Métodos: Foi realizado um estudo prospectivo de 43 olhos pseudofácicos vitrectomizados com glaucoma persistente após a remoção de óleo de silicone. Os pacientes foram randomizados para viscotrabeculotomia com irrigação da câmara anterior ou implante de válvula de Ahmed. Todos os pacientes foram examinados no primeiro dia, na primeira semana e 1, 3, 6, 9, 12, 18 e 24 meses após a cirurgia. Observaram-se complicações pós-operatórias. O sucesso foi definido como uma pressão intraocular entre 6 e 20 mmHg e uma redução da pressão intraocular >30% em comparação com a pressão intraocular pré-operatória. Resultados: Foram designados 22 olhos para o grupo da viscotrabeculotomia com irrigação da câmara anterior e 21 olhos para o grupo do implante de válvula de Ahmed. A pressão intraocular média pré-operatória foi de 35,5 ± 2,6 mmHg para o grupo da viscotrabeculotomia com irrigação da câmara anterior e pós- e de 35,5 ± 2,4 mmHg no grupo do implante de válvula de Ahmed. e Os valores pós-ope­ratórios foram de 16,9 ± 0,7 mmHg e 17,9 ± 0,9 mmHg para esses mesmos grupos, respectivamente (p<0,0001). Ambos os grupos tiveram uma redução estatisticamente significativa da pressão intraocular em relação aos valores pré-operatórios (p<0,0001) em todos os momentos do acompanhamento. A taxa de sucesso não qualificado nos grupos da viscotrabeculotomia com irrigação da câmara anterior e do implante de válvula de Ahmed foi de 72,73% e 61,9%, respectivamente. A complicação mais comum foi o hifema, autolimitado e mínimo. Conclusões: Tanto a viscotrabeculotomia com irrigação da câmara anterior quanto o implante de válvula de Ahmed são eficazes na redução da pressão intraocular no glaucoma após injeção de óleo de silicone, mas a viscotrabeculotomia com irrigação em câmara anterior proporcionou maior redução da pressão intraocular e maiores taxas de sucesso, com complicações mínimas.

5.
J Glaucoma ; 32(9): 807-814, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37054437

ABSTRACT

PRCIS: Angle procedures are safe and relatively effective for neonatal onset PCG. Watchful delay in intervention to close to the second month of life is helpful in ensuring diagnosis and making surgery more successful and easier. PURPOSE: The purpose of this study was to compare the surgical outcomes of visco-circumferential-suture-trabeculotomy (VCST) to rigid-probe double-entry viscotrabeculotomy (DEVT) and rigid-probe single-entry viscotrabeculotomy (SEVT) in infants with neonatal-onset primary congenital glaucoma (PCG). DESIGN: This was a retrospective chart review. PATIENTS AND METHODS: Retrospective chart review of 64 eyes of 64 infants with neonatal-onset PCG referred to Mansoura Ophthalmic Center in Mansoura, Egypt between February 2008 and November 2018. Study groups included VCST, DEVT, and SEVT, and follow-up covered 4 postoperative years. Complete (qualified) success was defined as intraocular pressure (IOP) ≤18 mm Hg and with 35% IOP reduction from baseline without (with) IOP-lowering medications or further surgical interventions, and without any sign of progression in corneal diameter, axial length, or optic disc cupping and without visual devastating complications. RESULTS: The mean±SD age at presentation and at the surgery of the study children was 3.63±1.74 and 55.23±1.60 days, respectively. The mean±SD IOP and cup/disc ratio of all study eyes at presentation and at final follow-up were 34.91±0.82 mm Hg and 0.70±0.09 and 17.04±0.74 mm Hg and 0.63±0.08, respectively. Complete success was achieved in 54.5%, 43.5%, and 31.6% in the VCST, DEVT, and SEVT groups, respectively. A self-limited hyphema was the commonest complication in all groups. CONCLUSIONS: Angle procedures are safe and marginally effective for the surgical treatment of neonatal-onset PCG, bringing IOP under control for at least 4 years of follow-up. Circumferential trabeculotomy as a first-line treatment has more favorable outcomes than rigid-probe SEVT. Rigid-probe viscotrabeculotomy offers an alternative to the noncompleted circumferential procedure.


Subject(s)
Glaucoma , Trabeculectomy , Infant , Infant, Newborn , Child , Humans , Trabeculectomy/methods , Glaucoma/surgery , Glaucoma/congenital , Intraocular Pressure , Retrospective Studies , Treatment Outcome , Sutures , Follow-Up Studies
6.
Small ; 19(22): e2207081, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36861293

ABSTRACT

Nanocomposites with enhanced mechanical properties and efficient self-healing characteristics can change how the artificially engineered materials' life cycle is perceived. Improved adhesion of nanomaterials with the host matrix can drastically improve the structural properties and confer the material with repeatable bonding/debonding capabilities. In this work, exfoliated 2H-WS2 nanosheets are modified using an organic thiol to impart hydrogen bonding sites on the otherwise inert nanosheets by surface functionalization. These modified nanosheets are incorporated within the PVA hydrogel matrix and analyzed for their contribution to the composite's intrinsic self-healing and mechanical strength. The resulting hydrogel forms a highly flexible macrostructure with an impressive enhancement in mechanical properties and a very high autonomous healing efficiency of 89.92%. Interesting changes in the surface properties after functionalization show that such modification is highly suitable for water-based polymeric systems. Probing into the healing mechanism using advanced spectroscopic techniques reveals the formation of a stable cyclic structure on the surface of nanosheets, mainly responsible for the improved healing response. This work opens an avenue toward the development of self-healing nanocomposites where chemically inert nanoparticles participate in the healing network rather than just mechanically reinforcing the matrix by slender adhesion.

7.
J Colloid Interface Sci ; 640: 1080-1088, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-36931011

ABSTRACT

Utilising the solid-state synthesis method is an easy and effective way to recycle spent lithium-ion batteries. However, verifying its direct repair effects on completely exhausting cathode materials is necessary. In this work, the optimal conditions for direct repair of completely failed cathode materials by solid-state synthesis are explored. The discharge capacity of spent LiCoO2 cathode material is recovered from 21.7 mAh g-1 to 138.9 mAh g-1 under the optimal regeneration conditions of 850 °C and n(Li)/n(Co) ratio of 1:1. The regenerated materials show excellent electrochemical performance, even greater than the commercial LiCoO2. In addition, based on the whole closed-loop recycling process, the economic and environmental effects of various recycling techniques and raw materials used in the battery production process are assessed, confirming the superior economic and environmental feasibility of direct regeneration method.

8.
Arq Bras Oftalmol ; 86(3): 223-231, 2023.
Article in English | MEDLINE | ID: mdl-35319653

ABSTRACT

PURPOSE: To compare viscotrabeculotomy with anterior chamber irrigation to Ahmed glaucoma valve implantation for secondary glaucoma following silicone oil removal. METHODS: A prospective study was conducted on 43 vitrectomized pseudophakic eyes with persistent glaucoma after silicone oil removal. Patients were randomized to either viscotrabeculotomy with anterior chamber irrigation or Ahmed glaucoma valve implantation. All patients were examined on day 1, week 1, and months 1, 3, 6, 9, 12, 18, and 24 postoperatively. Postoperative complications were noted. Success was defined as an intraocular pressure between 6 and 20 mmHg and with an intraocular pressure reduction of >30% compared with the preoperative intraocular pressure. RESULTS: There were 22 eyes in the viscotrabeculotomy with anterior chamber irrigation and 21 eyes in the Ahmed glaucoma valve implantation group. The mean preoperative and postoperative intraocular pressure in the viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation groups were 35.5 ± 2.6 mmHg and 35.5 ± 2.4 mmHg and 16.9 ± 0.7 mmHg and 17.9 ± 0.9 mmHg respectively (p˂0.0001). There was a statistically significant intraocular pressure reduction at all follow-up time points compared to preoperative values (p˂0.0001) in both groups. The unqualified success rate in the viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation groups were 72.73% and 61.9%, respectively. A minimal self-limited hyphema was the most common complication. CONCLUSIONS: Both viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation are effective in lowering the intraocular pressure in glaucoma after silicone oil removal with viscotrabeculotomy with anterior chamber irrigation providing greater reduction, higher success rates, and minimal complications.


Subject(s)
Glaucoma Drainage Implants , Glaucoma , Humans , Silicone Oils , Prospective Studies , Treatment Outcome , Follow-Up Studies , Glaucoma/surgery , Intraocular Pressure , Anterior Chamber/surgery , Prosthesis Implantation , Postoperative Complications/surgery , Retrospective Studies
9.
Nanoscale Adv ; 4(24): 5330-5342, 2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36540120

ABSTRACT

The photocatalytic degradation of uranium complexes is considered among the most efficient techniques for the efficient removal of uranium ions/complexes from radioactive wastewater. Described here is a nanostructured photocatalyst based on a cobalt-doped TiO2 composite with induced oxygen vacancies (Co@TiO2-C) for the photocatalytic removal of uranium complexes from contaminated water. The synergy between oxygen vacancies and Co-doping produced a material with a 1.7 eV bandgap, while the carbon network facilitates electron movement and hinders the e-h recombination. As a result, the new photocatalyst enables the decomposition of uranium-arsenazo iii complexes (U-ARZ3), followed by photocatalytic reduction of hexavalent uranium to insoluble tetravalent uranium. Combined with the nanosheet structure's high surface area, the photocatalytic decomposition, reduction efficiency, and kinetics were significantly enhanced, achieving almost complete U(vi) removal in less than 20 minutes from solution with a concentration as high as 1000 mL g-1. Moreover, the designed photocatalyst exhibits excellent stability and reusability without decreasing the photocatalytic performance after 5 cycles.

10.
Nanomicro Lett ; 14(1): 210, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36315314

ABSTRACT

The rapid improvement in the gel polymer electrolytes (GPEs) with high ionic conductivity brought it closer to practical applications in solid-state Li-metal batteries. The combination of solvent and polymer enables quasi-liquid fast ion transport in the GPEs. However, different ion transport capacity between solvent and polymer will cause local nonuniform Li+ distribution, leading to severe dendrite growth. In addition, the poor thermal stability of the solvent also limits the operating-temperature window of the electrolytes. Optimizing the ion transport environment and enhancing the thermal stability are two major challenges that hinder the application of GPEs. Here, a strategy by introducing ion-conducting arrays (ICA) is created by vertical-aligned montmorillonite into GPE. Rapid ion transport on the ICA was demonstrated by 6Li solid-state nuclear magnetic resonance and synchrotron X-ray diffraction, combined with computer simulations to visualize the transport process. Compared with conventional randomly dispersed fillers, ICA provides continuous interfaces to regulate the ion transport environment and enhances the tolerance of GPEs to extreme temperatures. Therefore, GPE/ICA exhibits high room-temperature ionic conductivity (1.08 mS cm-1) and long-term stable Li deposition/stripping cycles (> 1000 h). As a final proof, Li||GPE/ICA||LiFePO4 cells exhibit excellent cycle performance at wide temperature range (from 0 to 60 °C), which shows a promising path toward all-weather practical solid-state batteries.

11.
Adv Sci (Weinh) ; 9(30): e2203189, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36026564

ABSTRACT

Copper ions (Cu2+ ) disposed to the environment at massive scale pose severe threat to human health and waste of resource. Electrochemical deionization (EDI) which captures ions by electrical field is a promising technique for water purification. However, the removal capacity and selectivity toward Cu2+ are unsatisfying, yet the recycling of the captured copper in EDI systems is yet to be explored. Herein, an efficient electrochemical copper pump (ECP) that can deliver Cu2+ from dilute brackish water into much more concentrated solutions is constructed using carbon nanosheets for the first time, which works based on reversible electrosorption and electrodeposition. The trade-off between the removal capacity and reversibility is mediated by the operation voltage. The ECP exhibits a removal capacity of 702.5 mg g-1 toward Cu2+ and a high selectivity coefficient of 64 for Cu2+ /Na+ in the presence of multiple cations; both are the highest reported to date. The energy consumption of 1.79 Wh g-1 is among the lowest for EDI of copper. More importantly, the Cu species captured can be released into a 20-fold higher concentrated solution. Such a high performance is attributed to the optimal potential distribution between the two electrodes that allows reversible electrodeposition and efficient electrosorption.


Subject(s)
Copper , Water Purification , Humans , Water Purification/methods , Saline Waters , Carbon , Ions
13.
iScience ; 25(3): 103945, 2022 Mar 18.
Article in English | MEDLINE | ID: mdl-35281734

ABSTRACT

Wearable e-textiles have gained huge tractions due to their potential for non-invasive health monitoring. However, manufacturing of multifunctional wearable e-textiles remains challenging, due to poor performance, comfortability, scalability, and cost. Here, we report a fully printed, highly conductive, flexible, and machine-washable e-textiles platform that stores energy and monitor physiological conditions including bio-signals. The approach includes highly scalable printing of graphene-based inks on a rough and flexible textile substrate, followed by a fine encapsulation to produce highly conductive machine-washable e-textiles platform. The produced e-textiles are extremely flexible, conformal, and can detect activities of various body parts. The printed in-plane supercapacitor provides an aerial capacitance of ∼3.2 mFcm-2 (stability ∼10,000 cycles). We demonstrate such e-textiles to record brain activity (an electroencephalogram, EEG) and find comparable to conventional rigid electrodes. This could potentially lead to a multifunctional garment of graphene-based e-textiles that can act as flexible and wearable sensors powered by the energy stored in graphene-based textile supercapacitors.

14.
Small Methods ; 6(3): e2101613, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35152565

ABSTRACT

Metallic lithium batteries are holding great promises for revolutionizing the current energy storage technologies. However, the formation of dendrite-like morphology of lithium deposition caused by uneven distribution of Li+ might cause severe safety concerns of batteries. In this study, a polyoxometalate (POM) cluster, H5 PMo10 V2 O40 (PMo10 V2 ), is added to the conventional electrolyte that can construct a lithium-rich layer and inhibit the growth of Li dendrites effectively. The Li-rich layer can fill any lack of lithium ions on the surface of the metal anode, making the electric field strength consistent across the anode surface, thereby inhibiting the formation of lithium dendrites. Consequently, a significantly prolonged cyclic lifespan is obtained for both Li/Li symmetric cells and Li/LiCoO2 (Li/LCO) full cells. The cells with LCO positive maintains a high reversible specific capacity of 108.5 mAh g-1 after 300 cycles when electrolyte with PMo10 V2 additive is used, compared to 31.5 mAh g-1 for the untreated electrolyte. The findings indicate that POMs endowed as "ionic sponge" can be widely deployed in lithium metal batteries.

15.
Mikrochim Acta ; 189(1): 3, 2021 12 02.
Article in English | MEDLINE | ID: mdl-34855016

ABSTRACT

A dual-function organic-inorganic mesoporous structure is reported for naked-eye detection and removal of uranyl ions from an aqueous environment. The mesoporous sensor/adsorbent is fabricated via direct template synthesis of highly ordered silica monolith (HOM) starting from a quaternary microemulsion liquid crystalline phase. The produced HOM is subjected to further modifications through growing an organic probe, omega chrome black blue G (OCBBG), in the cavities and on the outer surface of the silica structure. The spectral response for [HOM-OCBBG → U(VI)] complex shows a maximum reflectance at λmax = 548 nm within 1 min response time (tR); the LOD is close to 9.1 µg/L while the LOQ approaches 30.4 µg/L, and this corresponds to the range of concentration where the signal is linear against U(VI) concentration (i.e., 5-1000 µg/L) at pH 3.4 with standard deviation (SD) of 0.079 (RSD% = 11.7 at n = 10). Experiments and DFT calculations indicate the existence of strong binding energy between the organic probe and uranyl ions forming a complex with blue color that can be detected by naked eyes even at low uranium concentrations. With regard to the radioactive remediation, the new mesoporous sensor/captor is able to reach a maximum capacity of 95 mg/g within a few minutes of the sorption process. The synthesized material can be regenerated using simple leaching and re-used several times without a significant decrease in capacity.

16.
Nanoscale ; 13(45): 19038-19048, 2021 Nov 25.
Article in English | MEDLINE | ID: mdl-34757347

ABSTRACT

There is growing demand for lightweight flexible supercapacitors with high electrochemical performance for wearable and portable electronics. Here, we spun nanoparticles of nickel-manganese oxides along with carbon nanotubes into carbon nanofibers and engineered a 3D networked Ni-Mn oxides/CNT@CNF free-standing membrane for flexible supercapacitor applications. The electrospinning process controlled the nanoparticle aggregation while subsequent heat treatment generates nanochannels in the fibres, resulting in a very porous tubular nanocomposite structure. The preparation process also enabled good interfacial contact between the nanoparticles and the conductive carbon network. The resulting Ni-Mn oxides/CNT@CNF membrane displays high mass loading (Ni-Mn oxides) of 855 mg cm-3 and low CNT incorporation of ∼0.4%. The outstanding porous structure, synergy of the carbon with Ni-Mn oxides, and fast and facile faradaic reactions on the electrode were responsible for the superior volumetric capacitance of 250 F cm-3 at 1 A cm-3, energy density as high as 22 mW h cm-3 and an excellent power density of 12 W cm-3. Despite the low CNT loading, the hybrid electrode exhibits excellent cycling performance with capacitance retention of 96.4% after 10 000 cycles evidencing a well-preserved Ni-manganese oxide nanostructure throughout the cycling. The resulting outstanding electrochemical performances of the Ni-Mn oxides/CNT@CNF synergic system offer new insights into effective utilization of transition metal oxides for establishing high-performance flexible supercapacitors within a confined volume.

17.
Int J Ophthalmol ; 14(4): 510-516, 2021.
Article in English | MEDLINE | ID: mdl-33875940

ABSTRACT

AIM: To evaluate the safety and efficacy of augmented trabeculotomy with Ologen versus perfluoropropane in management of pseudophakic glaucoma. METHODS: This is a comparative randomized study included 57 pseudophakic eyes of 57 patients with medically uncontrolled open angle glaucoma (OAG). Twenty-nine patients were allocated in group I (trabeculectomy with Ologen; trab-ologen group), while 28 patients were assigned in group II (trabeculectomy with perfluoropropane gas bubble; trab-C3F8 gas bubble group). RESULTS: The intraocular pressure (IOP) was significantly reduced in both study groups at all postoperative follow up intervals (1wk, 3, 6, 12, 18, 24, 30 and 36mo, P<0.001). The differences between the mean IOP values of both groups remained statistically insignificance during the early 12 months of follow up. However, the trab-ologen group achieved a statistically significant reduction over the trab-C3F8 gas bubble group during the last 24 months of follow up. CONCLUSION: Augmentation of trabeculectomy with either Ologen implant or perfluoropropane gas bubble are associated with strict long term IOP control and evident safety in medically-uncontrolled pseudophakic eyes with OAG.

18.
Int Ophthalmol ; 41(5): 1883-1893, 2021 May.
Article in English | MEDLINE | ID: mdl-33634342

ABSTRACT

PURPOSE: Identifying earlier retinal thickness affection and predictability for diabetic retinal neurodegeneration (DRN) in patients with type 2 diabetes mellitus (DM2) without diabetic retinopathy (DR). PATIENTS AND METHODS: This is a comparative cross-sectional study. Thirty-eight eyes of 19 patients with DM2 without any signs of DR and 38 eyes of 19 controls underwent retinal evaluation using optical coherence tomography. Macular ganglion cell layer (GCL), macular retinal nerve fiber layer (mRNFL), inner plexiform layer (IPL), total macular thickness, peripapillary retinal nerve fiber layer (pRNFL) and Bruch's membrane opening-minimum rim width (BMO-MRW) were evaluated. RESULTS: GCL showed significant thickness reduction in the total, superior and inferior halves as well as the 9 ETDRS regions (except the nasal and lower outer regions). The mRNFL showed a significant reduction in the total, superior and inferior halves as well as the lower and nasal outer regions. The IPL showed significant reduction in the 4 inner regions only. The pRNFL showed significant reduction in the total, superotemporal and inferotemporal sectors values. The BMO-MRW did not show any significant thickness change. CONCLUSION: The total, superior and inferior GCL and mRNFL, in addition to the global pRNFL were the most affected and predictive layers for DRN in patients with DM type 2 without DR. It appears that the GCL is the primary site of DRN and the rest of the changes represented a degeneration of the axonal path between the optic disk and the macular GCL.


Subject(s)
Diabetes Mellitus, Type 2 , Diabetic Retinopathy , Optic Disk , Cross-Sectional Studies , Diabetes Mellitus, Type 2/complications , Diabetic Retinopathy/complications , Diabetic Retinopathy/diagnosis , Humans , Retinal Ganglion Cells , Tomography, Optical Coherence
19.
Small ; 17(8): e2005745, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33522048

ABSTRACT

Rechargeable alkali metal-ion batteries (AMIBs) are receiving significant attention owing to their high energy density and low weight. The performance of AMIBs is highly dependent on the electrode materials. It is, therefore, quite crucial to explore suitable electrode materials that can fulfil the future requirements of AMIBs. Herein, a hierarchical hybrid yolk-shell structure of carbon-coated iron selenide microcapsules (FeSe2 @C-3 MCs) is prepared via facile hydrothermal reaction, carbon-coating, HCl solution etching, and then selenization treatment. When used as the conversion-typed anode materials (CTAMs) for AMIBs, the yolk-shell FeSe2 @C-3 MCs show advantages. First, the interconnected external carbon shell improves the mechanical strength of electrodes and accelerates ionic migration and electron transmission. Second, the internal electroactive FeSe2 nanoparticles effectively decrease the extent of volume expansion and avoid pulverization when compared with micro-sized solid FeSe2 . Third, the yolk-shell structure provides sufficient inner void to ensure electrolyte infiltration and mobilize the surface and near-surface reactions of electroactive FeSe2 with alkali metal ions. Consequently, the designed yolk-shell FeSe2 @C-3 MCs demonstrate enhanced electrochemical performance in lithium-ion batteries, sodium-ion batteries, and potassium-ion batteries with high specific capacities, long cyclic stability, and outstanding rate capability, presenting potential application as universal anodes for AMIBs.

20.
ACS Nano ; 15(2): 2506-2519, 2021 Feb 23.
Article in English | MEDLINE | ID: mdl-33463152

ABSTRACT

Chalcogenide-based anodes are receiving increasing attention for rechargeable potassium-ion batteries (PIBs) due to their high theoretical capacities. However, they usually exhibit poor electrochemical performance due to poor structural stability, low conductivity, and severe electrolyte decomposition on the reactive surface. Herein, a method analogous to "blowing bubbles with gum" is used to confine FeS2 and FeSe2 in N-doped carbon for PIB anodes with ultrahigh cyclic stability and enhanced rate capability (over 5000 cycles at 2 A g-1). Several theoretical and experimental methods are employed to understand the electrodes' performance. The density functional theory calculations showed high affinity for potassium adsorption on the FeS2 and FeSe2. The in situ XRD and ex situ TEM analysis confirmed the formation of several intermediate phases of the general formula KxFeS2. These phases have high conductivity and large interlayer distance, which promote reversible potassium insertion and facilitate the charge transfer. Also, the calculated potassium diffusion coefficient during charge/discharge further proves the enhanced kinetics. Furthermore, The FeS2@NC anode in a full cell also exhibits high cyclic stability (88% capacity retention after 120 cycles with 99.9% Coulombic efficiency). Therefore, this work provides not only an approach to overcome several challenges in PIB anodes but also a comprehensive understanding of the mechanism and kinetics of the potassium interaction with chalcogenides.

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