4th Cycle Research Articles

Preservation of Medicinal Plants of The Shipibo-Konibo Culture in Primary School Students

Objective: The purpose of the research is to determine the preservation of knowledge about medicinal plants of the Shipibo-Konibo culture in students of the 4th cycle of the Educational Institution No. 64872 B. Nuevo Paraíso of the Masisea district-2021 Theoretical Framework: The topics addressed are explained on the variable medicinal plants with a theoretical basis resulting from scientific research, taken from reliable sources published in impact journals and measurable results. Method: The study belongs to the quantitative approach, descriptive type and simple descriptive design. The population is made up of 160 students, from which a sample of 50 students was taken between third and fourth grade, to collect the information the survey technique and its instrument the survey form were applied to collect information on the knowledge of medicinal plants of the Shipibo Konibo culture. Results and Discussion: The results show that children maintain their knowledge of medicinal plants and there is a tendency to lose their use and knowledge of medicinal plants of the Shipibo Konibo culture. Implications of the research: Despite the existence of conventional medicine, the use of medicinal plants in the jungle is current, and their healing properties must be investigated in depth. Originality/Value: The importance of the research stands out fundamentally because the ancestral knowledge of medicinal plants is relevant and is an alternative and raw material for research in the field of medicine.

A real-world prospective analysis of the relationship between nanoliposomal irinotecan and fluorouracil with folinic acid and neutropenia in patients with pancreatic cancer (NAPOLEON-2 study, NN-2401).

762 Background: Nanoliposomal irinotecan and fluorouracil with folinic acid (NFF) is a standard regimen after gemcitabine-based chemotherapy (CTx) for unresectable or recurrent pancreatic cancer (urPC) patients. Neutropenia caused by systemic CTx has been reported to be a prognostic marker in several cancers, however, the relationship between neutropenia and efficacy of NFF in urPC patients is unknown. Therefore, we initiated a prospective observational study to investigate whether neutropenia can be a prognostic marker in the real-world (NN-2401), followed by a retrospective one (NN-2301). Methods: We collected the data of urPC patients treated with NFF who had received at least one previous CTx in 17 hospitals in Japan from June 2021 to October 2023. The primary endpoint was overall survival (OS). Secondary endpoints included the progression-free survival (PFS) and overall response rate (ORR). To analyze them, we divided urPC patients into three groups by the grade of the most severe neutropenia during NFF (Cutoff A, grade 0 vs 1-4; Cutoff B, grade 0-1 vs 2-4; Cutoff C, grade 0-2 vs 3-4). Besides that, we compared OS among the following three groups receiving NFF ≥4 cycles in Cutoff C; one showed neutropenia with NFF reduction after the 4th cycle (Cutoff C High-Late), another showed neutropenia with NFF reduction in the 2nd or 3rd cycle (Cutoff C High-Early), and the other did grade 0-2 neutropenia (Cutoff C Low). Results: Among the 150 patients, the number of patients with the most severe neutropenia of grade 0, 1, 2, 3, or 4 was 79, 7, 23, 34, and 7, respectively. The median OS of severe neutropenia group in Cutoff A, B, or C was 9.8, 9.8, and 10.6 months, respectively. Both OS and PFS were significantly better in all severe neutropenia groups; hazard ratio [HR] of OS for Cutoff A, B, or C was 0.58, 0.54, and 0.60, respectively; HR of PFS was 0.61, 0.56, and 0.56, respectively. Only Cutoff C showed a significant difference with an odds ratio of 3.06 (95% confidence interval [CI], 1.06-8.80; p=0.04) in ORR. Multivariate Cox regression analysis showed significant difference of OS in all Cutoffs; adjusted HR was 0.58 for Cutoff A, 0.53 for Cutoff B, and 0.52 for Cutoff C. Logistic regression analysis showed a significant difference in ORR of Cutoff C with an odds ratio of 4.02 (95%CI, 1.29-12.6; p=0.02). In addition, the numbers of patients were 73, 14, and 19 in Cutoff C Low, High-Late, and High-Early, respectively. The median OS of Cutoff C High-Late was significantly better than that of Cutoff C High-Early or Cutoff C Low (15.0 vs 10.4 or 9.1 months, p<0.05). Conclusions: In NFF treatment, neutropenia showed the usefulness as a prognostic marker for both OS and PFS, and also a predictive one for tumor response in urPC patients. The results are similar to our previous data, so we conclude that neutropenia can be a useful biomarker of NFF. Clinical trial information: UMIN000043939 .

Reversible Mg2+-Insertion/Deinsertion of Rutile TiO2 in Non-Corrosive Electrolytes

Abstract Single-crystal rutile TiO2 with a spindle morphology was investigated as a negative electrode material for Mg-ion batteries. In the electrolyte with ethylene carbonate and diethyl carbonate typically used for Li-ion batteries, the rutile TiO2 exhibited reversible capacities of 163 and 94 mA h g−1 at the first cycle and 50th cycle, respectively. The spindle structure developed in the c-axis direction should contribute easier Mg2+ diffusion inside the structure to improve utilization of the active material.

All-solid-state batteries designed for operation under extreme cold conditions

A pressing need for enhancing lithium-ion battery (LIB) performance exists, particularly in ensuring reliable operation under extreme cold conditions. All-solid-state batteries (ASSBs) offer a promising solution to the challenges posed by conventional LIBs with liquid electrolytes in low-temperature environments. In this study, leveraging the benefits of amorphous solid-state electrolytes (SSEs) xLi3N-TaCl5 (1 ≤ 3x ≤ 2), we develop ASSBs capable of functioning effectively under extreme cold conditions. The designed ASSBs, employing LiCoO2 positive electrode with a mass loading of 4.46 mg cm‒2 and a Li-In negative electrode, demonstrate initial discharge capacities of 183.19, 164.8 and 143.78 mAh g‒1 under 18 mA g‒1 at ‒10, ‒30, and ‒40 °C, respectively, and exhibit a final discharge capacity of 137.6 mAh g‒1 at 18 mA g‒1 and ‒30 °C in the 100th cycle. Moreover, the ASSBs demonstrate an initial discharge capacity of 51.94 mAh g‒1 at 18 mA g‒1 and ‒60 °C with cycling over 200 h.

Preparation and structural optimization of vanadium oxide nanotubes as cathode materials for PIBs with improved performance.

In this work, we synthesized hollow multi-walled vanadium oxide nanotubes (VO x -NT) using a soft template technique under hydrothermal reaction conditions. By replacing organic templates, which do not contribute to electrochemical potassium storage, with K+ in a solution environment, we effectively retained the original hollow multi-walled structure of VO x -NT while obtaining the K-VO x -NT material. We conducted systematic characterizations of the microstructure, morphology, and composition of these materials and evaluated their potassium storage performance. Compared to the original VO x -NT, K-VO x -NT exhibited significantly enhanced cycling stability and rate performance when serving as the cathode in potassium-ion batteries (PIBs). It demonstrated a reversible discharge specific capacity of 75.7 mA h g-1 for the 1st cycle at a current density of 50 mA g-1 within a voltage range of 1.5-3.8 V (vs. K+/K) and retained 62.2 mA h g-1 after the 50th cycle. When a current density of 600 mA g-1 was applied, it could still deliver a capacity of 44.3 mA h g-1. Furthermore, the storage and degradation mechanisms of K+ in K-VO x -NT were elucidated. In addition, using hard carbon as the anode, the K-VO x -NT full-cell was tested to further evaluate its practical performance. This work provides insight into the design and modification of vanadium-based cathode materials for future PIBs.

Enhanced NiO-CaO-based multifunctional material pellets with Ce and La oxides on aluminosilicate support for sorption-enhanced chemical looping steam reforming of glycerol

Multifunctional materials in pellet form composed of NiO-CaO-based aluminosilicate support have been developed for hydrogen (H2) production via sorption-enhanced chemical looping steam glycerol reforming (SE-CL-SGR). The effect of CaO content (50–70 wt%) and an addition of promoter (CeO2 and La2O3) on material properties and H2 production performances were investigated. A good H2 production of 90 %v/v purity for 75 mins has been achieved from 15 wt% NiO, 70 wt% CaO, and 30 wt% aluminosilicate support (15Ni(70Ca.30S)) pellets. However, it totally showed a loss of CO2 adsorption ability by the 5th cycle as a formation of carbon caused the pellet cracking. Rare-earth oxides such as CeO2 and La2O3 have been incorporated into the structure to improve the mechanical properties. An addition of 5 wt% La2O3 (5La-15Ni(70Ca.30S)) provides superior H2 production performance to that with CeO2 and without rare-earth as 95 %v/v H2 purity can be constantly produced for 60 mins throughout five testing cycles. These enhancements indicate that the CeO2 and La2O3 modifications effectively improve the multifunctional material pellet performance and stability, making it suitable for large-scale hydrogen production applications.

Study on the Stress Accumulation Characteristics of a Rotating Metal Hydride Reactor

The reactor is the core device used in guaranteeing the alloy's stable high-level reversible hydrogen storage. This work investigates a rotating reactor as new structure to alleviate stress accumulation using inertial force and counterforce, compared to typical statics reactors. The rotating reactor’s strain and response exhibited notable differences in the whole five stages at the 8th absorption/desorption cycle. In the cycle of vertical reactor, plastic deformation began by the 4th cycle, followed by a rapid linear increase in strain values leading swiftly to failure in the 19th cycle. When inverted, plastic deformation began by the 17th cycle and fracture occurred after 29th cycles, and for rotating reactor at 1.39 rpm, the curve of stress accumulation changed gently, sudden fracture occurred after 36th cycles. Particle size distribution of rotating reactor was skewed toward the large size as a herald of more strong anti-pulverization. Meanwhile, the expansion area was located in lower part, and the bulging notably shifted upwards compared to vertical reactor. This was attributed to the fact that the dynamic inertial force and counterforce effect improved the uniformity of alloy filling and prevented the formation of high-density areas at the representative bottom obviously alleviating local stress concentration phenomena.

Time-varying deposition strategy for comprehensive properties improvement of bionic bidirectional gradient NiTi alloy fabricated by laser directed energy deposition

ABSTRACT Inspired by the property mechanism principles of C. squamiferum (impact resistance) and bamboo (energy absorption), a bionic bidirectional gradient NiTi alloy was developed and fabricated by the innovative time-varying deposition strategy (TVDS), including different process parameters (the laser power and scanning speed), different scanning paths (alternative optimised spiral pattern and x-axis rotation pattern) and interlayer interval time. This study explores how TVDS influences the printability, microstructure evolution, phase transformation behaviour, mechanical properties, and superelasticity response. However, the element distribution tests discover mutation points under various regions in the GD-X-GD-Z (V1) and GD-X-LD (H1) planes to determine the feasibility of the bionic bidirectional gradient using TVDS. The recovery ratios along the H1 and V1 planes after 1st and 10th cycles are 90.7% and 88.4%, 82.6% and 67.5%, respectively. The numerical modelling framework is established to elucidate the thermal fields generated by TVDS and provide support for the experimental data.

Évaluation du vieillissement de quatre huiles végétales utilisées en friture par la méthode d’illumination structurée (SLIPI-1p)

The aging of oils poses a significant challenge to food safety. This study evaluates the impact of repeated use of four frying oils (palm oil, sunflower oil, soybean oil, and extra virgin olive oil) during chicken frying, using the Structured Laser Illumination Planar Imaging (SLIPI-1p) technique at 450 nm. This method, which involves spatially modulating the intensity of a laser sheet with a diffraction grating, enables precise degradation analysis by measuring extinction coefficients. Fifteen samples of each oil were analyzed at specific temperatures and wavelengths. Additionally, the physicochemical properties of these oils were characterized according to AOAC standards, allowing for the correlation of measured optical properties with established quality standards. Sunflower oil remained usable up to the 10th frying cycle (78 minutes, extinction < 0.439 ± 0.001 mm⁻¹), while soybean oil maintained quality up to the 9th frying cycle (71 minutes, extinction < 0.488 ± 0.001 mm⁻¹). Palm oil showed significant degradation after the 6th frying cycle (49 minutes, extinction > 0.570 ± 0.002 mm⁻¹). Extra virgin olive oil reached degradation thresholds after 100 minutes of use, approximately at the 13th frying cycle (extinction > 0.680 ± 0.002 mm⁻¹). This study reveals that extra virgin olive oil is the most resistant to degradation, whereas palm oil is particularly sensitive to degradation. The results provide recommended usage thresholds for each oil and highlight the effectiveness of laser sheet imaging as a promising tool for assessing the quality of cooking oils. Keywords: Oil aging; Frying; Food safety; SLIPI-1p; Extinction coefficients.

In Vitro Regeneration of Bambusa Vulgaris Var. Striata Using Nodal Explants

The current study aimed to develop an effective micropropagation protocol for Bambusa vulgaris var. striata, through direct organogenesis using nodal explant. The maximum axillary bud break (84%) with the greatest number of shoots per explant (5.20 ± 0.37) was achieved using liquid MS medium containing 2.5 mg/l BAP and 1.5 mg/l TDZ, while the maximum length of shoots (7.12 ± 0.27 cm) was induced on 2.0 mg/l BAP. Shoots were multiplied in stirred liquid MS medium with 3.0 mg/l BAP, resulting in the highest number of shoots per culture (13.20 ± 0.58) with the shoot length of 7.32 ± 0.48 cm. BAP in combination with TDZ resulted in a feeble response to shoot proliferation; although in some cases, the presence of TDZ with BAP was inhibitory. The shoots progressively increased in number and length over the first four subculture cycles in the aforementioned medium, but declined in the 5th sub-culture cycle. Following the 4th sub-culture cycle, each culture produced 16.60 ± 0.60 shoots with an average length of 8.96 ± 0.61 cm. Adding 10% coconut water to the medium resulted in excellent shoot growth and development, with an average of 18.40 ± 1.44 shoots per culture, measuring 8.56 ± 0.79 cm. Half-strength MS medium with 3.0 mg/l IBA resulted in the highest rooting percentage (85%) and the most roots per culture (8.00 ± 0.71). Successful acclimatization of well-rooted clumps of 3-4 shoots was achieved in a mixture of soil, sand, and compost (2:1:1) with 85% survival rate. Bangladesh J. Bot. 53(4): 939-947, 2024 (December)

Hydrothermal сarbonization of Spirogyra sp. algae for adsorption and regeneration of malachite green dye

In this study, we prepared hydrochar (HCSP) from Spirogyra sp. algae (SP) as adsorbent to eliminate malachite green (MG) dye and conducted the adsorbent regeneration study. SP and HCSP were characterized using FTIR, XRD, SEM, and BET. The adsorption performance was evaluated under various conditions of pH, contact time, concentration, and temperature. SP and HCSP were optimum at pH 8 for MG adsorption. The suitable adsorption kinetics model was PSO, and the adsorption isotherm model tended to be the Freundlich model. The maximum adsorption capacity (Qmax) obtained from Langmuir calculation at 30 °C, SP and HCSP were 34.96 mg/g and 99.01 mg/g, respectively. The thermodynamic parameters indicated endothermic and spontaneous processes, with HCSP exhibiting greater adsorption capacity and spontaneity than SP. Regeneration studies demonstrated that HCSP and SP materials could be reused up to the 4th cycle with the remaining efficiency of 69.37% and 49.30%, respectively. Compared to SP, HCSP has better adsorption capacity.

Synthesis and characterization of Fe3O4@TiO2@Zeolite nanocomposite adsorbent for the removal of Levoflaxin antibiotic from environmental water matrices

The presence of pharmaceuticals in water matrices has been a major problem because of its expected adverse consequences on oceanic biological systems and human well-being. Levofloxacin (Levo), a persistent and widely used antibiotic, has emerged as a significant pollutant in water samples. Its resistance to conventional water treatment processes poses challenges for its removal. This work focuses on preparing and characterizing a magnetic nanocomposite adsorbent (Fe3O4@TiO2@Zeolite) designed to efficiently remove levofloxacin from the water samples, leveraging the Fe₃O₄ properties for easy separation and recovery of the adsorbent, TiO2 for its adsorption capacity, while zeolite’s porous structure and high ion-exchange capacity improve adsorption efficiency. Together, these materials create a robust, multifunctional composite with promising applications for pollutant removal from aqueous environments. The adsorption of Levo antibiotic exhibited excellent fitting to both the pseudo-second-order model (R2 = 1) and the Langmuir isotherm (R2 = 0.9240) together with the Freundlich isotherm (R2 = 0.999). Furthermore, the thermodynamic analysis indicated that the adsorption process of Levo was spontaneous and endothermic. This implies that the interaction between Levo and the Fe3O4@TiO2@Zeolite nanocomposite, developed in this study, is favourable and requires energy input. The Fe3O4@TiO2@Zeolite nanocomposite demonstrated a promising efficacy in the removal of Levo from wastewater samples, with removal percentage ranging between 92.43 and 96.95%. The prepared Fe3O4@TiO2@Zeolite composite material could be regenerated up to the 5th cycle. This highlights the potential of the nanocomposite as an effective remedy for the purification of wastewater contaminated with Levo.

Experimental and modeling insights into the kinetics of calcium looping CO2 capture process: Assessment of limestone treatment

This investigation aimed to offer a precise and detailed understanding of the intricate mechanisms governing the rapid and diffusion stages of carbonation within the calcium looping process, while also exploring the effects of treatment on mineral limestone (Raw limestone) as the primary sorbent for CO2 capture. Two modified samples treated with acetic acid (Acidified limestone) and hydrophobic silica nanoparticles (Silica-mixed limestone), were analyzed to provide deeper insights into the kinetics of the slow and fast stages of the carbonation reaction. The Acidified limestone had a significant influence on the carbonation conversion rates of both the rapid and slow stages, resulting in a notable enhancement in conversion efficiency. Notably, the carbonation conversion rates in the 20th cycle were measured as 0.201, 0.348, and 0.231 for the Raw, Acidified, and Silica-mixed limestones, respectively. An increase in the number of reaction cycles led to an increased percentage contribution of the diffusion stage, a decrease in transition time and consequently, a reduction in the overall carbonation conversion rate. Specifically, the share percentage of carbonation conversion for the diffusion stage in the 20th cycle was determined as 31.55%, 34.88%, and 30.36% for the Raw, Acidified, and Silica-mixed limestones, respectively. The results obtained from the modeling application demonstrated a reduction in the maximum absolute error with an increase in the reaction cycles. Additionally, the prediction results indicated that the carbonation conversion rates for the Raw and Acidified limestones in the 100th cycle were determined to be 0.07 and 0.12, respectively.

Exploration on antifreeze potential of thawed drip enzymatic hydrolysates on myofibrillar proteins in pork patties during freeze-thaw cycles

This study explored using small molecular weight hydrolysates from enzymolyzed thawed drip as cryoprotectants to preserve myofibrillar protein quality in pork patties during freeze-thaw cycles. Hydrolysates were added at 0.36 %, 0.72 %, and 1.4 % concentrations, compared to a control with deionized water and a positive control with sorbitol and sucrose. Results indicated that thawed drip hydrolysates significantly reduced thawing loss and cooking loss. Moreover, the color deterioration during the 3rd and 6th freeze-thaw cycles was delayed. Myofibrillar protein denaturation and oxidation in the experimental groups were inhibited, shown by decreased surface hydrophobicity, reduced carbonyl groups and protein surface roughness, and increased free sulfhydryl groups, α-helix content, and protein particle height. The highest hydrolysate concentration (1.4 %) provided the most benefits, performing comparably to the positive control. Correlation analysis confirmed that hydrolysates enhanced both myofibrillar protein and pork quality, offering a promising approach to improve meat resilience against freeze-thaw conditions.

High-Performance Cathodes Prepared via Liquid-Phase Method and Catalyzed by Co9S8 for All-Solid-State Lithium-Sulfur batteries

While all-solid-state lithium batteries and lithium-sulfur batteries are two advanced systems beyond the current generation of lithium-ion batteries and have been extensively studied for years, their combination (i.e., all-solid-state lithium-sulfur batteries, ASSLSBs) is seldomly explored. This paper herein demonstrates the success of making high-performance lithium sulfide cathodes for ASSLSBs. The composite cathode consists of the active material Li2S, a sulfide solid electrolyte Li6PS5Cl, a conductive carbon Ketjen Black, and a catalyst Co9S8 nanoparticles. Its preparation has the following features: mixing precursors via a liquid-phase method, in situ making Li6PS5Cl via calcination, and adding Co9S8 in the liquid-phase stage. Owing to the presence of Co9S8 nanoparticles and the liquid-phase process for ensuring excellent solid–solid interfaces among electrode constituents, the maximum capacity of the obtained electrode with Li2S-loading of 2 mg/cm2 in Li-In|Li6PS5Cl|cathode batteries is enhanced by 0.8 times and the maintaining capacity at the 100th cycle by 4.3 times. With high loadings of 10 mg/cm2, the cathode achieves a high areal capacity of 6.4 mAh/cm2 at room temperature, equivalent to energy densities of 598 Wh/kg, and maintain the retention ratio of over 80 % after 100 cycles. At 60 ℃, ultrahigh areal capacities of 9.4 mAh/cm2 and 14.1 mAh/cm2 can be achieved, equivalent to energy densities of 872 Wh/kg and 653 Wh/kg. Moreover, the mechanistic studies reveal that Co9S8 catalyzes all Li2S and also expedites the conversion between Li2S ↔ S by suppressing the polysulfides intermediates. Thus, this work opens the door of making high-performance Li2S cathodes for developing practical ASSLSBs.

Reduced graphene oxide – CeO2 nanocomposites for photocatalytic dye degradation

Over the past few decades, the widespread use of dyes has led to considerable environmental pollution, posing serious threats to human health and ecosystems. In this context, here focus on a tailored nanocomposite comprising reduced graphene oxide (rGO) and cerium oxide (CeO2) to eradicate methylene blue (MB) dye. The fabrication process involves a facile synthesis wherein CeO2 nanoparticles are anchored onto rGO sheets through co-precipitation treatment by mixing a precursor salt of cerium with graphene oxide (GO) in presence of reducing agent. The resulting nanocomposites were characterized using X-ray diffraction (XRD) analysis which confirms the crystallite size of CeO2 and rGO-CeO2 determined to be 21.61 nm and 10.74 nm respectively. Further FE-SEM analysis vividly illustrates the relatively spherical form of CeO2, which is dispersed on the rGO surface and energy dispersive X-ray spectroscopy (EDX) results provide clear evidence of the presence of carbon, cerium and oxygen in the composite. Additionally, Fourier-transform infrared spectroscopy (FTIR) confirms the composition of the rGO-CeO2 nanocomposites demonstrating the existence of various oxygen-containing groups, including O–H, C=O and Ce–O bonds. Thermogravimetric analysis (TGA) highlights that the rGO-CeO2 nanocomposites exhibits higher thermal stability with only 21.88 % weight loss up to 400 °C. Moreover, the photocatalytic activity of rGO-CeO2 nanocomposite exhibits a remarkable 94.92 % degradation of MB dye within 80 min under optimal conditions of UV light irradiation (λ = 254 nm), with a catalyst dosage of 7 mg in a 20 ppm of MB dye solution at pH 9. In contrast, pristine rGO and CeO2 achieved only 32.27 % and 38.48 % in 100 and 90 min respectively. The kinetics of photocatalysis process were meticulously studied and revealed that they followed pseudo-second order kinetic model suggesting chemisorption of MB dye onto nanocomposites prior to degradation. The stability of the nanocomposite was assessed under optimal conditions, demonstrating robust MB degradation (78 %) even up to the 4th cycle. Overall, the successful outcomes of this study show significant potential for degrading MB dye in wastewater by using the rGO-CeO2 nanocomposite.

Adsorption, antibacterial and molecular dynamic studies of bentonite clay–gemini (Bt–16-4-16) hybrid material

This work reports the preparation of a novel hybrid material, integrating a gemini surfactant, butane-1,4-bis(hexadecyldimethylammonium) dibromide, 16-4-16, into bentonite clay (raw Bt), which possessed the ability to remove tartrazine dye (TD) from aqueous solutions. The Bt-16-4-16 hybrid material was characterized through FT-IR, XRD, SEM, EDX, and BET. The results were further compared with previously reported Bt–16-3-16 hybrid material (prepared using propane-1,3-bis(hexadecyldimethylammonium) dibromide, 16-3-16, gemini surfactant). The Bt-16-4-16 and Bt–16-3-16 demonstrated around 97–98 % removal efficiency towards TD under specific experimental conditions examined ([TD] = 10 mg L−1, [adsorbent] = 2 g L−1, pH = 3, equilibrium time = 60 min, temperature = 298.15 K). With the rise in [TD] (from 1 to 100 mg L−1), the hybrid materials showed a prominent rise in adsorption capacity from 0.51 to 44.36 mg g−1 for Bt-16-4-16 and 0.50 to 42.61 mg g−1 for Bt-16-3-16. The efficiency of Bt–16-4-16 and Bt-16-3-16 in the removal of TD was not influenced much by the presence of various cations (Mg2+, Ca2+, Ni2+, Cu2+) and anions (EDTA, sulphate, HCO3¯and SO42−). The presence of 0.1 M NaCl caused a 0.05 % and 1.43 % decrease in the removal efficiency of Bt-16-4-16 and Bt-16-3-16, respectively. The results followed pseudo-second-order adsorption kinetics and agreed with the Freundlich isotherm. The Bt-16-4-16 and Bt-16-3-16 achieved maximum adsorption capacities of 128.7 and 117.8 mg g−1 against TD. The adsorption thermodynamics revealed that the process at the adsorbent's solid-liquid interfaces is entropy-driven, spontaneous, and endothermic. Both Bt-16-4-16 and Bt-16-3-16 were found to be reusable even after the 5th cycle. The Bt–16-4-16 showed a strong affinity towards TD and quickly reached maximum adsorption capacity at a relatively low fugacity of ≤15 kPa. Further, the antibacterial property of Bt-16-4-16 and Bt-16-3-16 was also tested.

MOF incorporated Polyethersulfone/Polylactic Acid ultrafiltration membranes for the catalytic removal of dyes via persulfate activation

This study synthesized novel nanocellulose/zeolitic Imidazolate Framework nanocomposite blended Polyethersulfone/Polylactic Acid (PES/PLA-CNF@ZIF-8) membranes through a modified phase inversion process. This is the first time that a nanocellulose-MOF composite catalytic nanomaterial has been synthesized and used as an additive in polymeric membranes. The morphology and chemical structure of the membranes and nanoparticles were characterised by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Fourier transform infrared (FTIR) respectively. Membrane wettability and crystalline structure were characterised by contact angle, and X-ray diffraction (XRD) analysis respectively. CNF@ZIF-8 modified membranes showed improved contact angle which decreased from 76° in the pristine membranes to 40° in 2 wt% membranes, bulk porosity increased from 74.3.3 % to 81.06 % while the pure water flux increased from 208.30 Lm-2h−1 to 348.73 Lm-2h−1. Further, the modified membranes showed an increase in surface roughness reaching 84.14 nm in 2 wt% membranes. The synthesized membranes have been used as catalysts in the activation of persulfate to degrade Rhodamine B dye. The modified membranes displayed a high catalytic effect (>90 %) in activating persulfate to degrade RhB dye when compared to pristine membranes which showed a degradation efficiency of < 35 %. The study found that the optimum parameters for pH, membrane (catalyst) dosage, oxidant and initial dye concentration were 5, 0.3 g, 0.4 mM and 10 ppm respectively. Quenching experiments showed that •SO4- and •OH radicals were responsible for the dye degradation, with •SO4- radicals playing a major role in the oxidative degradation of the RhB dye. The synthesized membranes showed good stability when tested within five cycles, with the membranes showing degradation efficiency ranging from 92.1 % in the 1st cycle to 91.9 % in the 3rd cycle, before decreasing to 75.3 % in the 5th cycle. This study has therefore shown that the synthesized PES/PLA-CNF@ZIF-8 membranes have potential for use as catalysts in the degradation of cationic dyes in wastewater treatment through persulfate activation.

Improvement of LiNi0.8Co0.1Mn0.1O2 Positive-Electrode Properties by Introducing Fluorinated Propionic Acid Ester-Based Solvent to Highly Concentrated Lin(SO2F)2 Electrolyte Solutions

IntroductionFurther improvement in energy density and safety of lithium-ion batteries is required to expand the spread of EVs. A LiNi0.8Co0.1Mn0.1O2 (NCM811) positive-electrode is drawing attention because it can deliver a high discharge capacity of about 220 mAh g-1 or more by raising the charging upper limit potential to 4.6 V (vs. Li/Li+). In general, however, the electrolyte solution is oxidized and decomposed at about 4 V (vs. Li/Li+) or more, and cracks of the NCM811 particles occur, which results in a significant decrease in charge and discharge performance. Accordingly, highly concentrated electrolyte solutions are attracting attention because of their high stability against oxidation and thermal stability1, while the problem is that the viscosity is high and the ion conductivity is low.In this study, flame-retardant tris (2,2,2-trifluoroethyl) phosphate (TFEP)-based electrolyte solutions containing high concentrations of LiN(SO2F)2 (LiFSI) were prepared, and methyl 2,3,3,3-tetrafluoropropionate (4FMP) as a co-solvent and methyl perfluoropropionate (5FMP) as a diluent were introduced to reduce the viscosity and improve the ion conductivity. The charge-discharge characteristics of NCM811 positive-electrodes were investigated by conducting charge-discharge tests over 100 cycles in a voltage range of 3.0-4.6 V using a half-cell with an NCM811 working electrode and a lithium metal counter electrode.ExperimentalThe nearly saturated 2.2 M LiFSI/TFEP (TFEP/Li+=1.7 by mol) electrolyte solution, and the highly concentrated LiFSI/TFEP+4FMP (TFEP:4FMP=1:1 and 2:1 by vol.) and LiFSI/TFEP+5FMP (TFEP/Li+=1.7 by mol, TFEP:5FMP=1:1, 2:1 and 3:1 by vol.) electrolyte solutions were prepared. An NCM811 composite electrode (13 mmf) was used as a working electrode and a Li foil (14 mmf) was used as a counter electrode, and each electrolyte solution was used to prepare a Li|NCM811 cell. Charge-discharge tests were conducted between 3.0 and 4.6 V. The charge/discharge rate in the first cycle was set to C/10, which corresponds to a current that can theoretically complete each charge (discharge) process in 10 h under the presumption that the theoretical specific capacity of NCM811 is 278 mAh/g. In addition, the NCM811 working electrode after 100 cycles was washed with dimethyl carbonate, dried, and then analyzed by a field emission scanning electron microscope (FE-SEM)/energy dispersive X-ray spectroscopy (EDX). To evaluate the oxidation resistance of the electrolyte solutions, linear sweep voltammetry (LSV) was performed by using three-electrode cell having a Pt working electrode (12 mmf).Results and DiscussionFigure 1 shows the changes in discharge capacity of Li|NCM811 cells in 100 cycles. 2.1 M LiFSI/TFEP+4FMP (TFEP: 4FMP=2:1 by vol., (TFEP+4FMP)/Li+=2.3 by mol., 4FMP electrolyte) and 1.6 M LiFSI/TFEP+5FMP (TFEP: 5FMP=2:1 by vol., 5FMP-diluted electrolyte) showed the highest performance among the 4FMP- and 5FMP-diluted electrolyte solutions, respectively. After 100 cycles, the discharge capacity retention was 92.5% and 93.1% in the 4FMP- and 5FMP-diluted electrolytes, respectively. In addition, the average Coulomb efficiency reached 99.0% and 99.3%, respectively. The 4FMP electrolyte showed the highest discharge capacity in the 100th cycle (209.0 mAh/g), and the 5FMP-diluted electrolyte showed the highest discharge capacity retention and average Coulomb efficiency. After the 100 charge-discharge cycles, the F atomic concentrations on the surface of NCM811 were 11.6% and 10.1% in 4FMP- and 5FMP-diluted electrolytes, respectively, which was the lowest among the 4FMP and 5FMP-diluted electrolyte solutions. LSV of Pt showed a large anodic current due to the oxidative decomposition of the 4FMP electrolyte, suggesting that the charge-discharge performance of NCM811 is improved by forming a thin and uniform protective film on it. On the other hand, since the oxidation decomposition current of the 5FMP-diluted electrolyte was kept at the lowest level, the charge-discharge performance of NCM811 should be improved by the high stability against oxidation of the electrolyte solution. Figure 1

Cycle Performance of Si Film Negative Electrodes with Lithium Fluoride Coating As an Artificial SEI

Introduction There is a growing need for high-capacity lithium-ion batteries as a power source for electric vehicles and a backup power source for renewable energy. Si negative electrodes, which have about ten times the capacity of conventional graphite electrodes, are expected to be used practically to increase the capacity of lithium-ion batteries. However, there are still issues that need to be addressed before Si electrodes can be used practically. One of them is the decomposition of electrolytes on the negative electrode surface. In conventional lithium-ion batteries, a small amount of additive such as FEC is added to the electrolyte to suppress electrolyte decomposition. However, suppression of the electrolyte decomposition is still difficult for Si electrodes. On the other hand, it has been found that lithium fluoride (LiF) in the SEI film formed from the decomposition products of the electrolyte improves charge and discharge properties of Si electrode.1-3 In this study, we aimed to suppress electrolyte decomposition and improve cycle life by forming a LiF layer as an artificial SEI on the Si electrode using a thin-film technique. Experimental Amorphous Si thin films, 100 nm in thickness, were prepared on copper foil by RF magnetron sputtering. Subsequently, LiF layers were deposited on the Si surfaces by sputtering with varying thicknesses. The thickness of the LiF layers was measured by a stylus surface profiler. The LiF-coated Si films were transferred to an Ar-filled glovebox without exposure to air and punched into disks 13 mm in diameter. A coin-type half-cell (CR2032) was assembled with the LiF-coated Si film as a working electrode and a Li disk of 14 mm in diameter as a counter electrode. A solution of 1 M LiPF6 dissolved in a mixture of ethylene carbonate and diethyl carbonate was used as an electrolyte. Charge and discharge characteristics were measured with a C/3 rate in a thermostatic chamber at 30°C. After cycling, the coin cells were disassembled in the glovebox, the Si electrodes were rinsed with dimethyl carbonate, and the Si electrode surfaces were observed with a scanning electron microscope (SEM). Result and Discussion Figure 1 shows variations in discharge capacity of the Si film electrodes with and without LiF coating. The discharge capacity of the Si electrode without LiF rapidly dropped after 10 cycles, but LiF coating significantly improved cyclability. Capacity retention at the 100th cycle, compared to that at the 5th cycle, increased from 4% without LiF to 52% with LiF coating. LiF coating also improved initial Coulombic efficiency from 89.9% to 92.5%, suggesting that LiF coating suppresses electrolyte decomposition. Si electrode surfaces after 30 cycles were observed by SEM as shown in Fig. 2. Exfoliation of the Si film without LiF was observed in many areas after 30 cycles, but it was suppressed by LiF coating. LiF coating is effective in improving the cycle performance of Si negative electrodes as an artificial SEI. Acknowledgments This work was supported by GteX Program Japan Grant Number JPMJGX23S3 and JSPS KAKENHI Grant Number 2201967.