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The commercialization of lithium-sulfur (Li-S) batteries is greatly hindered due to serious capacity fading caused by the polysulfide shuttling effect. Optimizing the structural configuration, enhancing reaction kinetics of the sulfur cathode, and increasing areal sulfur loading are of great significance for promoting the commercial applications of Li-S batteries. Herein, the multifunctional polysulfide scavengers based on nitrogen, sulfur co-doped carbon cloth (DCC), which is supported by flower-like MoS2 (1T-2H) decorated with BaMn0.9 Mg0.1 O3 perovskite particle (PrNP) and carbon nanotubes (CNTs), namely, DCC@MoS2 /PrNP/CNTs, are delicately designed and synthesized. The physical confinement, chemical coupling, and catalysis conversion for active sulfur are achieved simultaneously in this polysulfide motif. Due to these merits, the as-fabricated self-supported DCC@MoS2 /PrNP/CNTs/S manifests an excellent reversible areal capacity of 4.75 mAh cm-2 with an ultrahigh sulfur loading of 5.2 mg cm-2 at the 50th cycle. The outstanding cycling stability is obtained upon 800 cycles with a large reversible capacity of 871 mAh g-1 and a negligible fading rate of 0.02% per cycle at a rate of 1.0 C, suggesting its promising prospects for the commercial success of high-performance Li-S batteries toward flexible electronic devices and energy storage equipment.
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LiNi0.8Co0.1Mn0.1O2 (NCM) layered oxide is contemplated as an auspicious cathode candidate for commercialized lithium-ion batteries. Regardless, the successful commercial utilization of these materials is impeded by technical issues like structural degradation and poor cyclability. Elemental doping is among the most viable strategies for enhancing electrochemical performance. Herein, the preparation of surface tellurium-doped NCM is done by utilizing the methodology solid-state route at high temperatures. Surface doping of the Te ions leads to structural stability owing to the inactivation of oxygen at the surface via the binding of slabs of transition metal-oxygen. Remarkably, 1 wt% of Te doping in NCM exhibits enhanced electrochemical characteristics with an excellent discharge capacity, i.e., 225.8 mAh/g (0.1C), improved rate-capability of 156 mAh/g (5C) with 82.2% retention in capacity (0.5C) over 100 cycles within 2.7-4.3V as compared to all other prepared electrodes. Hence, the optimal doping of Te is favorable for enhancing capacity, cyclability along with rate capability of NCM.
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Mn-rich P2-type layered oxide cathode materials suffer from severe capacity loss caused by detrimental phase transition and transition metal dissolution, making their implementation difficult in large-scale sodium-ion battery applications. Herein, we introduced a high-valent Sb5+ substitution, leading to a biphasic P2/O3 cathode that suppresses the P2-O2 phase transformation in the high-voltage condition attributed to the stronger Sb-O covalency that introduces extra electrons to the O atom, reducing oxygen loss from the lattices and improving structural stability, as confirmed by first-principle calculations. Besides, the enhanced Na+ diffusion kinetics and thermodynamics in the modified sample are associated with the enlarged lattice parameters. As a result, the proposed cathode delivers a discharge capacity of 142.6 mAh g-1 at 0.1C between 1.5 and 4.3 V and excellent performance at a high mass loading of 8 mg cm3 with a specific capacity of 131 mAh g-1 at 0.2C. Furthermore, it also possesses remarkable rate capability (90.3 mAh g-1 at 5C), specifying its practicality in high-energy-density sodium-ion batteries. Hence, this work provides insights into incorporating high-valent dopants for high-performance Mn-rich cathodes.
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[This retracts the article DOI: 10.7759/cureus.29931.].
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Rational design and synthesis of multifunctional electrocatalysts with high electrochemical activity and low cost are significantly important for new-generation lithium-sulfur (Li-S) batteries. Herein, N-doped FeP nanospheres decorated N doped carbon matrix is successfully synthesized by facile one-pot pyrolysis and in-situ phosphorization technique to mitigate the conversion kinetics and suppress the shuttle effect. The large specific surface area with mesopores can incorporate up to 81.5% sulfur, with the conductive carbon and nitrogen co-matrix providing Li+/e- passage and fastening the redox kinetics. The remarkable adsorption properties and the electrocatalytic activity through physical confinement and chemical immobilization is thoroughly verified. Consequently, the FeP/CN@S deliver a high reversible capacity of 1183 mAh g-1 at 0.1C compared to Co/P/CN@S (961 mAh g-1); whereas, at 1C, a negligible decay rate of 0.04% is observed for 1000 cycles, possessing outstanding cycling stability and rate capability. Hence, the cost-effective in-situ phosphorization strategy to synthesize FeP/CN@S as an efficient nanoreactor is constructive to be applied in Li-S batteries.
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Exploring impressively effective dielectric nanofluids for transformers to improve dielectric strength and thermal stability is indispensable. It is crucial to determine the modification mechanism of dispersed nanomaterials in insulating oil for operative applications in power transformers. This paper aspires to authenticate the experimental evidence of the enhancing AC dielectric strength of synthetic ester Midel-7131 using two newly introduced semiconductive nanoparticles, CdS and Co3O4, and uncover the potential reasons for enhanced AC dielectric strength. The AC breakdown voltage (BDV) of synthetic ester and nanofluids was investigated and statistically evaluated. The mean AC breakdown voltage of SE/CdS and SE/Co3O4 was increased by 31.9% and 31.3%, respectively. The augmentation in AC breakdown strength is possibly due to the facilitated charge-scavenging ability owing to the large specific surface area and wide bandgap. Simultaneous thermogravimetric analysis, differential scanning calorimetry, and derivative thermogravimetry analyses (TGA-DSC-DTG) confirmed that the initial decomposition temperature was high and heat dissipation was low, indicating that the nanofluids were thermally stable in both air and nitrogen. Hence, emerging semiconductive CdS and Co3O4-based nanofluids of synthetic ester possess remarkable dielectric strength and thermal stability enhancement for their application in power transformers.
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Immunoglobulin M (IgM) plays a regulatory role in subsequent immune response development, thereby accelerating the production of immunoglobulin G (IgG) with high affinity. Selective IgM deficiency (SIGMD) is a rare immune disorder that has been reported in association with serious infections, such as bacteremia. Patients commonly present with infections, atopy, septicemia, splenomegaly, neoplasia, and other autoimmune disorders. Treatment modalities and recommendations range from careful monitoring to vaccinations, aggressive management of respiratory infections, preventive and therapeutic antibiotics, and intravenous immunoglobulin (IVIG). There is insufficient information to generalize patients' prognosis with selective IgM deficiency due to the small number of patients and lack of prospective studies. We hereby present the case of a 28-year-old male with multiple recurrent boils, cellulitis, and osteomyelitis who has been diagnosed with selective IgM deficiency and is being treated with IVIG. This case report highlights the diagnostic evaluation and therapeutic care of patients with SIGMD and the need for follow-up.
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Warfarin is a widely known oral anticoagulant used for the treatment and prevention of thromboembolic conditions. A rare, crippling, and occasionally fatal complication of warfarin is skin necrosis, resulting in significant morbidity and mortality. Due to the disease's unknown pathophysiology and rare occurrence, the treatment guidelines are not well established. We present the case of a 14-year-old female with a history of mitral stenosis and atrial fibrillation who had been on warfarin for the last two years and now develops an acute excruciating rash within three days of reinitiation of warfarin despite enoxaparin bridging and a normal blood clotting profile. After cessation of warfarin, the skin necrosis progressed to eschar formation and resolved within four weeks. To prevent further complications, early diagnosis and treatment with intravenous vitamin K, fresh frozen plasma (FFP), and aggressive wound care are essential. The prognosis may be improved by prompt diagnosis and drug cessation.
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The current meta-analysis aims to assess the efficacy and safety of sodium glucose cotransporter 2 (SGLT2) inhibitors in individuals with diabetes and chronic kidney disease (CKD). The current meta-analysis was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search was conducted to identify all relevant studies related to the efficacy and safety of SGLT2 inhibitors in individuals with diabetes and CKD. The search was undertaken in PubMed, EMBASE, and Cochrane Library from January 2000 to September 2022. The primary efficacy outcome assessed in the current meta-analysis included major adverse cardiovascular events (MACE). Other efficacy outcomes included all-cause mortality and change in hemoglobin A1c (HbA1c) (%). Safety outcomes included serious adverse events, acute kidney injury, hypoglycemia, and hyperkalemia. In total 11 articles met the inclusion criteria and were included in the final analysis enrolling 27520 patients (14491 in the SGLT2 inhibitors and 13029 in the placebo group). The findings of this meta-analysis have shown that the risk of MACE and all-cause mortality was significantly lower in patients receiving SGLT2 inhibitors. Additionally, Hb1AC change was also significantly greater in SGLT2 inhibitors group. In relation to safety outcomes, serious adverse events, risk of acute kidney injury, and hyperkalemia were significantly lower in the SGLT2 inhibitors group. The SGLT2 inhibitors significantly decreased the risk of major cardiovascular events and all-cause mortality in patients with CKD and diabetes. Furthermore, SGLT2 inhibitor is also effective in reducing Hb1Ac levels in patients.
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Statins can play an essential role in the tertiary and primary prevention of cardiovascular events by reduction of cholesterol in a stroke patient. This meta-analysis aims to assess statin therapy's effect on mortality and recurrence of Intracranial Hemorrhage (ICH) in patients with spontaneous ICH. The current meta-analysis was conducted following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A systematic search was performed using PubMed, EMBASE, and Cochrane Library to identify studies assessing the use of statins in patients with ICH. The primary outcome assessed in the current meta-analysis was a hemorrhagic stroke. The secondary outcomes included cardiac-related events and all-cause mortality. A total of 9 studies were included in the current meta-analysis enrolling 49027 patients, with 8094 patients on statin therapy and 40933 patients in the control group. The risk of recurrent ICH was significantly lower in patients receiving stains (RR: 0.81, 95% CI: 0.67-0.99, p-value: 0.02) compared to placebo. However, no significant differences were observed regarding all-cause mortality (RR: 0.80, 95% CI: 0.53-1.20, p-value: 0.27) and cardiovascular events (RR: 1.24, 95% CI: 0.88-1.74). In ICH patients, statins can reduce the risk of recurrent ICH in patients with a history of ICH. However, statins had no significant effect on all-cause mortality and cardiovascular events.
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Post-traumatic unilateral carotid cavernous fistula (CCF) with ipsilateral symptoms is a rare occurrence, so its diagnosis frequently gets overlooked for other more common conditions. Timely imaging with digital subtraction angiography (DSA) and appropriate vascular intervention is essential in preventing potentially serious sequelae in such cases. We describe a case of post-traumatic CCF in a 42-year-old man who experienced intermittent headaches and right eye redness, proptosis, and watery discharge for three months following the incident. He was diagnosed with a right CCF based on DSA. Timely endovascular embolization with the coiling method resulted in obvious relief of the ocular symptoms and an improved prognosis. This article offers a description of our patient, a brief discussion of the existing literature, the challenges of diagnosing such cases, and a variety of therapy options.
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The use of antimalarial drugs for prophylaxis is a widespread practice while traveling to underdeveloped nations, particularly those with a high malaria prevalence. Chloroquine is still one of the most commonly recommended antimalarials, either alone or in combination with others, for prophylaxis. However, its increased use over the past few decades has been associated with many adverse effects, including headaches, dizziness, vomiting, and diarrhea, as well as neuropsychiatric symptoms such as psychosis. Here, we discuss the case of a 30-year-old Asian man who, after starting a 500-milligram (mg) prophylactic dosage of chloroquine per week, developed psychotic symptoms. This case highlights the need to use chloroquine and other antimalarials with care, especially when beginning as a prophylactic measure with the lowest suggested dosage.
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Adequate periprocedural anticoagulation is important to prevent complications like transient ischemic attack, stroke, severe esophageal injury, and pulmonary vein stenosis. The aim of this meta-analysis was to compare uninterrupted anticoagulation therapy with interrupted anticoagulation therapy for patients with arrhythmias undergoing catheter ablation. The current meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Several online databases were searched, such as PubMed, Cochrane Library, and Embase, to search for relevant randomized controlled trials (RCTs). The primary outcome included thromboembolic events. Secondary outcomes included major bleeding events and minor bleeding events. A total of eight RCTs were included in the current meta-analysis, encompassing a total of 3893 patients. No significant differences were reported in relation to thromboembolic events (RR: 2.39, 95% CI: 0.41-13.97, p-value: 0.33), major bleeding events (RR: 0.99, 95% CI: 0.50-1.96, p-value: 0.98) and minor bleeding events (RR: 1.55, 95% CI: 0.56-4.30, p-value: 0.40) between the two study groups. This meta-analysis did not find any conclusive evidence for the absence of any difference between the two strategies.
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Designing sulfur host materials with unique functions such as physical constraint or chemical catalysis to suppress the shuttle effect and promote the fast conversion of polysulfides is a prerequisite for lithium-sulfur batteries (LSBs). Herein, we construct hollow Co(OH)2 nanotubes connected by Ti3C2Tx nanosheets (denoted as Co(OH)2@Ti3C2Tx) as host materials for sulfur through a simple self-assembly method at room temperature. The large void spaces of Co(OH)2 nanotubes not only confine higher sulfur loading but also mitigate the volumetric expansion in the process of lithiation. Moreover, the conductive Ti3C2Tx layers facilitate fast electron transfer and catalyze the transition of sulfur based on the terminations on the surface. Combining those two materials can also act as an efficient polysulfide anchor to enable outstanding electrochemical performance. The Co(OH)2@Ti3C2Tx@S cathode presents a high discharge capacity of 1400 mAh g-1 at 0.1C and long-cycling stability at 1C for 500 cycles. Moreover, the obtained capacity of Li2S precipitation and the dissolution capacity reach 193.3 and 291.1 mAh g-1, respectively. Consequently, this work demonstrates a facile strategy to design multifunctional materials that effectively confine the polysulfides and enhance the performance of LSBs.
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A crucial challenge for the commercialization of Ni-rich layered cathodes (LiNi0.88Co0.09Al0.03O2) is capacity decay during the cycling process, which originates from their interfacial instability and structural degradation. Herein, a one-step, dual-modified strategy is put forward to in situ synthesize the yttrium (Y)-doped and yttrium orthophosphate (YPO4)-modified LiNi0.88Co0.09Al0.03O2 cathode material. It is confirmed that the YPO4 coating layer as a good ion conductor can stabilize the solid-electrolyte interface, while the formative strong Y-O bond can bridle TM-O slabs to intensify the lattice structure in the state of deep delithium (>4.3 V). In particular, both the combined advantages effectively withstand the anisotropic strain generated upon the H2-H3 phase transition and further alleviate the crack generation in unit-cell dimensions, assuring a high-capacity delivery and fast Li+ diffusion kinetics. This dual-modified cathode shows advanced cycling stability (94.1% at 1C after 100 cycles in 2.7-4.3 V), even at a high cutoff voltage and high rate, and advanced rate capability (159.7 mAh g-1 at 10C). Therefore, it provides a novel solution to achieve both high capacity and highly stable cyclability in Ni-rich cathode materials.
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The LiNi1- x- yCo xAl yO2 (NCA)-layered materials are regarded as a research focus of power lithium-ion batteries (LIBs) because of their high capacity. However, NCA materials are still up against the defects of cation mixing and surface erosion of electrolytes. Herein, a novel design strategy is proposed to obtain a heterostructured cathode material with a high-capacity LiNi0.88Co0.09Al0.03O2 layer ( R3Ì m) core and a stable LiNi0.5Mn1.5O4-like spinel ( Fd3Ì m) shell, which is prepared through spontaneous redox reaction of the precursor with KMnO4 in an alkaline solution and subsequent calcination procedure. The structure, morphology, element distribution, and electrochemical performances of the as-prepared NCA are studied by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical techniques. The results show that the LiNi0.5Mn1.5O4-like spinel ( Fd3Ì m) shell layer with a robust cubic close-packed crystal structure is uniformly adhered to the surface of the NCA and can availably suppress the side reactions with the electrolyte and surface-phase transformation, which will facilitate insertion/extraction of Li+ ions during cycling. Benefiting from the enhanced structural stability and improved kinetics, the heterostructured NCA delivers a better cycling performance. The discharge specific capacity is as high as 153.7 mA h g-1 at 10 C, and even at high charge voltage of 4.5 V, the capacity retention can still increase 11% at 1 C (200 mA g-1) after 100 cycles. Besides, the material exhibits a prominent thermal stability of 248 °C at 4.3 V. Therefore, this novel structure design strategy can contribute to the development and commercialization of high-performance cathode materials for power LIBs.
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A high sulfur loading cathode is the most crucial component for lithium-sulfur batteries (LSBs) to obtain considerable energy density for commercialization applications. The major challenges associated with high sulfur loading electrodes are poor material utilization caused via the nonconductivity of the charged product (S) and the discharged product (Li2S), poor stability arisen from dissolution of lithium polysulfides (LiPSs) into most organic electrolytes and pulverization, and structural damage of the electrode caused by large volumetric expansion. A multifunctional synergistic composite enables ultrahigh sulfur content for advanced LSBs, which comprises the sulfur particle encapsulated with an ion-selective polymer with conductive carbon nanotubes and dispersed around Magnéli phase Ti4O7 (MS-3) by the bottom-up method. The ion-selective polymer provides a physical shield and electrostatic repulsion against the shuttling of polysulfides with negative charge, whereas it can permit the transmission of lithium ion (Li+) through the polymer membrane, and the carbon nanotubes twined around the sulfur promote electronic conductivity and sulfur utilization as well as strong chemical adsorption of LiPSs by means of Ti4O7. Because of this hierarchical construction, the cathode possesses a lofty final sulfur loading of 72% and large sulfur areal mass loading of 3.56 mg cm-2, which displays the large areal specific capacity of 4.22 mA h cm-2. In the same time, it can provide excellent cyclic performance with the corresponding capacity attenuation ratio of 0.08% per cycle at 0.5 C after 300 cycles. Especially, while sulfur areal mass loading is sharply enhanced to 5.11 mg cm-2, the MS-3 composite exhibits a large initial areal capacity of 5.04 mA h cm-2 and still keeps a high reversible capacity of 696 mA h g-1 at 300th cycle even at a 1.0 C. The design of high sulfur content cathodes is a viable approach for boosting practical commercialized application of LSBs.
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Li-rich layered oxides (LLOs) with high specific capacities are favorable cathode materials with high-energy density. Unfortunately, the drawbacks of LLOs such as oxygen release, low conductivity, and depressed kinetics for lithium ion transport during cycling can affect the safety and rate capability. Moreover, they suffer severe capacity and voltage fading, which are major challenges for the commercializing development. To cure these issues, herein, the synthesis of high-performance antimony-doped LLO nanofibers by an electrospinning process is put forward. On the basis of the combination of theoretical analyses and experimental approaches, it can be found that the one-dimensional porous micro-/nanomorphology is in favor of lithium-ion diffusion, and the antimony doping can expand the layered phase lattice and further improve the lithium ion diffusion coefficient. Moreover, the antimony doping can decrease the band gap and contribute extra electrons to O within the Li2MnO3 phase, thereby enhancing electronic conductivity and stabilizing lattice oxygen. Benefitting from the unique architecture, reformative electronic structure, and enhanced kinetics, the antimony-doped LLO nanofibers possess a high reversible capacity (272.8 mA h g-1) and initial coulombic efficiency (87.8%) at 0.1 C. Moreover, the antimony-doped LLO nanofibers show excellent cycling performance, rate capability, and suppressed voltage fading. The capacity retention can reach 86.9% after 200 cycles at 1 C, and even cycling at a high rate of 10 C, a capacity of 172.3 mA h g-1 can still be obtained. The favorable results can assist in developing the LLO material with outstanding electrochemical properties.
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"Assisted phytoextraction" involving application of chemical additives such as plant growth regulators (PGRs) has become a trend in phytoremediation technology. This study identifies a cost-effective, naturally available crude PGR (PGR1) that produces the same effects as the commercial PGR (PGR2), increasing metal uptake by plants and the reduction of metal stress. Assisted phytoextraction by pearl millet (Pennisetum glaucum) from a multi-metal (Cd, Cr, Cu, Fe, Na and Zn) contaminated soil medium with tannery solid waste (TSW) soil amendments of 5 and 10%, was evaluated in a full-factorial pot trial with PGR1, PGR2 and Trichoderma pseudokoningii as factors. The effects of these phytoextraction assistants were measured through dry biomass production, heavy metal uptake, stress tolerance enzymes catalase (CAT) and superoxide dismutase (SOD), soluble protein content of plant, and phytoextraction efficiency. Dry biomass and multi-metal accumulation were the highest in the soil treatments with a combined application of PGR1, PGR2 and T. pseudokoningii and the lowest in the control. The soluble protein contents and the SOD and CAT values were the highest in the 10% TSW treatment provided with PGR2+T. pseudokoningii, while the lowest were in the control. Thus, application of crude PGR in combination with other phytoextraction assistants can increase biomass production as well as multi-metal accumulation in plants. However, the biochemical properties of the plant depend on the level of TSW stress in the soil treatment as well as the type of phytoextraction assistants.