Study on the Adsorption of Trace Water in N-Methyl-pyrrolidone Solvents by A-Type Molecular Sieves.

N-Methyl-pyrrolidone (NMP) is an important coating solvent for the production of lithium batteries, and its water content will greatly affect the coating quality and energy density of lithium batteries, which needs to be reduced to 200 ppm. The current vacuum distillation technology suffers from high operating costs and high energy consumption, whereas the pervaporation technology only achieves solvent dehydration up to 99.5%. Therefore, it is of great significance to carry out the study of trace water removal from NMP solvents. In this paper, the A-type molecular sieve adsorption method was used to remove trace water from the NMP solvent, and the effects of molecular sieve type, particle size, adsorption temperature, feeding amount, and contact time on the dehydration performance of NMP system were first investigated. Adsorbed at 25 °C for 240 min at a feeding amount of 120 g/L, 3A molecular sieves were able to reduce the water content of the NMP solvent from 5000 to 140 ppm. Second, Langmuir and Freundlich equations were used to fit the static isothermal adsorption data, and the results showed a better correlation of the Langmuir equation. Then, the adsorption kinetics and diffusion mechanism were analyzed by the kinetic model and the Crank single-pore diffusion model. The R2 of the pseudo-first-order kinetic model was 0.9993, which was more suitable for describing the process of adsorption of water from the NMP solvent by 3A molecular sieves, and the effective diffusion coefficient De = 2.986 × 10-8 cm2/s was calculated for the Crank single-pore adsorption model, which proved water molecules on the 3A molecular sieve. The diffusion of water molecules on the inner surface of the pores is the controlling step of the adsorption process. Finally, the fixed-bed dynamic penetration curves were investigated to obtain the experimental data of fixed-bed adsorption, and the experimental data were fitted using the Thomas and Yoon-Nelson models, which showed that both models could describe the adsorption behavior of trace water in NMP solvents on 3A molecular sieves. This study provides a new idea for the removal of trace water in NMP systems, and a series of model fitting parameters provide basic data for industrial scale-up.

Hierarchical Ni3V2O8@N-Doped Carbon Hollow Double-Shell Microspheres for High-Performance Lithium-Ion Storage.

Transition metal oxides (TMOs) are highly dense in energy and considered as promising anode materials for a new generation of alkaline ion batteries. However, their electrode structure is disrupted due to significant volume changes during charging and discharging, resulting in the short cycle life of batteries. In this paper, the hierarchical Ni3V2O8@N-doped carbon (Ni3V2O8@NC) hollow double-shell microspheres were prepared and used as electrode materials for lithium-ion batteries (LIBs). The utilization efficiency and ion transfer rate of Ni3V2O8 were improved by the hollow microsphere structure formed through nanoparticle self-assembly. Furthermore, the uniform N-doped carbon layer not only enhanced the structural stability of Ni3V2O8, but also improved the overall electrical conductivity of the composite. The Ni3V2O8@NC electrode has an initial discharge capacity of up to 1167.3 mAh g-1 at a current density of 0.3 A g-1, a reversible capacity of up to 726.5 mAh g-1 after 200 cycles, and still has a capacity of 567.6 mAh g-1 after 500 cycles at a current density of 1 A g-1, indicating that the material has good cycle stability and high-rate capability. This work presents new findings on the design and fabrication of complex porous double-shell nanostructures.

Thermodynamic and Mechanistic Analyses of Direct CO2 Methylation with Toluene to para-Xylene.

Direct CO2 methylation with toluene, as one of the CO2 hydrogenation technologies, exhibits great potential for the CO2 utilization to produce the valuable para-xylene (PX), but the tandem catalysis remains a challenge for low conversion and selectivity due to the competitive side reactions. The thermodynamic analyses and the comparation with two series of catalytic results of direct CO2 methylation are conducted to investigate the product distribution and possible mechanism in adjusting the feasibility of higher conversion and selectivity. Based on the Gibbs energy minimization method, the optimal thermodynamic conditions for direct CO2 methylation are 360-420 °C, 3 MPa with middle CO2/C7H8 ratio (1:1 to 1:4) and high H2 feed (CO2/H2 = 1:3 to 1:6). As a tandem process, the toluene feed would break the thermodynamic limit and has the higher potential of >60% CO2 conversion than that of CO2 hydrogenation without toluene. The direct CO2 methylation route also has advantages over the methanol route with a good prospect for >90% PX selectivity in its isomers due to the dynamic effect of selective catalysis. These thermodynamic and mechanistic analyses would promote the optimal design of bifunctional catalysts for CO2 conversion and product selectivity from the view of reaction pathways of the complex system.

Direct Catalytic Asymmetric and Regiodivergent N1- and C3-Allenylic Alkylation of Indoles.

Herein we report a Pd-catalyzed asymmetric allenylic alkylation strategy for the direct functionalization of 1H-indoles by employing P-chiral BIBOP-type ligands. The regioselectivity (N1/C3) of this process can be switched efficiently. Using Cs2 CO3 at elevated temperatures in MeCN, N1-alkylated indoles bearing axial chirality with a stereocenter non-adjacent (ß) to the nitrogen are produced in good yields with high enantioselectivity and complete N1-regioselectivity regardless of the electronic properties and substitution patterns of diverse indoles. Using K2 CO3 at room temperature in CH2 Cl2 , chiral C3-alkylated indoles can also be obtained. Notably, we introduce a new class of tri-substituted allenylic electrophiles that proceeded through different pathways from di-substituted allenylic electrophiles.

miR-330 targeting BCO2 is involved in carotenoid metabolism to regulate skin pigmentation in rainbow trout (Oncorhynchus mykiss).

BACKGROUND: MicroRNAs (miRNAs) play a critical role in regulating skin pigmentation. As a key economic trait, skin color directly affects the market value of rainbow trout (Oncorhynchus mykiss), however, the regulatory mechanism of most miRNAs in fish skin color is still unclear. RESULTS: In this study, the full-length cDNA sequence of ß-carotene oxygenase 2 (BCO2, a key regulator of carotenoid metabolism) from the rainbow trout was obtained using rapid-amplification of cDNA ends (RACE) technology, and qRT-PCR was used to investigate the differential expression of miR-330 and BCO2 in 14 developmental stages and 13 tissues between wild-type rainbow trout (WTrt) and yellow mutant rainbow trout (YMrt). Additionally, the function of miR-330 was verified by overexpression and silencing in vitro and in vivo. The results showed that the complete cDNA sequence of BCO2 was 2057 bp with a 1707 bp ORF, encoding a 568 amino acid protein having a molecular weight of 64.07 kD. Sequence alignment revealed that higher conservation of BCO2 protein amongst fishes than amongst other vertebrates, which was further confirmed by phylogenetic analysis. The analysis of spatial and temporal expression patterns suggested that BCO2 and miR-330 were abundantly expressed from fertilized-stage to multi-cell as well as in the dorsal and ventral skin of WTrt and YMrt, and their expression patterns were opposite in most of the same periods and tissues. In vitro, luciferase reporter assay confirmed that BCO2 was a direct target of miR-330, and transfection of miR-330 mimics into rainbow trout liver cells resulted in a decrease in the expression of BCO2; conversely, miR-330 inhibitor had the opposite effect to the miR-330 mimics. In vivo, miR-330 agomir significantly decreased BCO2 expression in dorsal skin, tail fin, and liver. Furthermore, overexpression of miR-330 could suppress cell proliferation and induce apoptosis. CONCLUSION: Our results showed that miR-330 is involved in the regulation of skin pigmentation in rainbow trout by targeting BCO2 and shows its promise as a potential molecular target to assist the selection of rainbow trout with better skin color patterns.

Effects of explosive strength training on lower limbs in taekwondo athletes / Efeitos do treinamento com força explosiva sobre os membros inferiores em atletas de taekwondo / Efectos del entrenamiento con fuerza explosiva en miembros inferiores en atletas de taekwondo

ABSTRACT Introduction: Taekwondo is a sport of highly competitive intensity, and the gain in physical fitness of its practitioners is a work that involves analysis of combat techniques, sports biomechanics, and theories of physical training. However, studies of current methods, such as explosive strength training, are still superficial. Objective: Study the effect of different explosive strength training protocols on the lower limbs of taekwondo athletes. Methods: 24 taekwondo athletes were randomly selected as volunteers and divided into experimental and control groups. These were subdivided to perform traditional and different strength training combinations. The experiment lasted eight weeks, with the first four weeks dedicated to strength training adaptation. Data on body shape, maximal strength, explosive strength, and fitness were collected for statistical comparison. Results: Through repeated measures analysis of variance to test lower limb explosive strength on exercise level, it can be seen that there is a significant difference between the test data before and after the approach (P<0.05), this difference was not observed in the control group (P>0.05). The mean value of all indexes in the experimental group was higher than in the control group. Conclusion: Explosive strength training and its different combinations on lower limbs can significantly improve the physical fitness of taekwondo athletes. The different combinations of strength training presented can be used as an effective resource in the lower limbs athletes' explosive strength gain. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: O Taekwondo Competitivo é um esporte de alta intensidade competitiva e o ganho na aptidão física de seus praticantes é um trabalho que envolve análise das técnicas de combate, biomecânica esportiva e teorias de treinamento físico. Porém, o estudo de métodos recentes, como o treinamento de força explosiva, ainda é superficial. Objetivo: Estudar o efeito de distintos protocolos de treinamento de força explosiva sobre os membros inferiores em atletas de Taekwondo. Métodos: 24 atletas de taekwondo foram aleatoriamente selecionados como voluntários e divididos em grupos experimental e de controle. Estes foram subdivididos para a execução do treinamento de força tradicional combinado com diferentes combinações de treinamento de força. O experimento durou 8 semanas, sendo as 4 primeiras dedicadas à adaptação do treino de força. Dados sobre forma corporal, força máxima, força explosiva e aptidão física foram coletados para comparação estatística dos resultados. Resultados: Através da análise de medidas repetidas de variância para testar a força explosiva dos membros inferiores segundo o nível de exercício, pode-se ver que existe uma diferença significativa entre os dados do teste antes e depois da abordagem (P<0,05), essa diferença não foi observada no grupo controle (P>0,05). O valor médio de todos os índices do grupo experimental foi maior que no controle. Conclusão: O treinamento de força explosiva e suas diferentes combinações sobre os membros inferiores pode melhorar significativamente a aptidão física dos atletas praticantes de taekwondo. As diferentes combinações de treinamento de força apresentadas podem ser utilizadas como um recurso eficaz no ganho sobre a força explosiva dos membros inferiores desses atletas. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

Resumen Introducción: El Taekwondo Competitivo es un deporte de alta intensidad competitiva y la progresión en aptitud física de sus practicantes es un trabajo que implica el análisis de las técnicas de combate, la biomecánica deportiva y las teorías del entrenamiento físico. Sin embargo, los estudios sobre métodos recientes, como el entrenamiento de fuerza explosiva, siguen siendo superficiales. Objetivo: Estudiar el efecto de diferentes protocolos de entrenamiento de fuerza explosiva sobre los miembros inferiores en atletas de Taekwondo. Métodos: Se seleccionaron aleatoriamente 24 atletas de taekwondo como voluntarios y se dividieron en grupos experimental y de control. Éstos se subdividieron para realizar un entrenamiento de fuerza tradicional compuesto con diferentes combinaciones de entrenamiento de fuerza. El experimento duró 8 semanas, las 4 primeras dedicadas a la adaptación al entrenamiento de fuerza. Se recogieron datos sobre la forma corporal, la fuerza máxima, la fuerza explosiva y la forma física para la comparación estadística de los resultados. Resultados: Mediante el análisis de varianza de medidas repetidas para probar la fuerza explosiva de las extremidades inferiores según el nivel de ejercicio, se observa que hay una diferencia significativa entre los datos de la prueba antes y después del abordaje (P<0,05), esta diferencia no se observó en el grupo de control (P>0,05). El valor medio de todos los índices en el grupo experimental fue superior al del grupo de control. Conclusión: El entrenamiento de la fuerza explosiva y sus diferentes combinaciones en las extremidades inferiores pueden mejorar significativamente la forma física de los atletas de taekwondo. Las diferentes combinaciones de entrenamiento de fuerza presentadas pueden utilizarse como un recurso eficaz en la obtención de fuerza explosiva de los miembros inferiores de estos atletas. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Preparation of High Stability Pd/Ceramic/Ti-Al Alloy Composite Membranes by Electroless Plating.

High stability Pd/ceramic/Ti-Al alloy composite membranes were prepared by electroless plating. Ceramic membranes fabricated by an in situ oxidation method were used as an inter-diffusion barrier between the Pd layer and the Ti-Al alloy support of the membranes to prevent intermetallic diffusion. The stabilities of the ceramic membranes at high temperatures in an H2 atmosphere were investigated. The permeation performances and stabilities of the Pd/ceramic/Ti-Al alloy composite membranes were also studied. The results showed that the thickness, pore size, and microstructure of the ceramic membranes did not change significantly after the treatment in an H2 atmosphere at high temperatures, indicating that the ceramic membranes prepared by the in situ oxidation method were stable in an H2 atmosphere at high temperatures. The thickness of the Pd layer was ~13 µm. The hydrogen permeability and H2/N2 selectivity of the Pd composite membranes at 773 K were 2.13 × 10-3 mol m-2 s-1 Pa-0.5 and 600, respectively. In addition, the H2 flux, N2 flux, and H2/N2 selectivity of the composite membranes remained nearly constant over three heat cycles (under the same conditions), indicating that the structures of the Pd/ceramic/Ti-Al alloy composite membranes were stable.

[Sources, Distribution of Main Controlling Factors, and Potential Ecological Risk Assessment for Heavy Metals in the Surface Sediment of Hainan Island North Bay, South China].

The distribution characteristics of the content of As, Cr, Cu, Hg, Pb, Zn, and Cd were researched based on the geochemical analysis of 159 surface sediment samples in Haikou Bay, Puqian Bay, Dongzhai Harbor, and Mulan Bay Mathematical statistics methods were used to interpret the sources of heavy metals, and the main controlling factors for heavy metal distribution were confirmed, having been analyzed qualitatively and semi-quantitatively. The results showed that the average contents of As, Cd, Cr, Cu, Hg, Pb, and Zn were 8.40, 0.06, 32.50, 8.32, 0.02, 18.77, and 35.87 µg·g-1, respectively. High contents of Cr, Cu, Hg, Pb, and Zn are mainly distributed in estuaries and harbors. The content of As increased gradually from south to north in the research area, while Cd gathered mainly in Haikou Bay. The source of Cu, Zn, Hg, Pb, Cr, and Cd in sediment was terrestrial input, which was controlled by anthropogenic pollution and migration of weathered products from mother rock. The source of As could be overseas material input. The grain size of sediment was the main factor controlling the contents of Cu, Zn, Hg, Pb, and Cr, and it was found that sediments with a finer grain size have more heavy metals adsorbed. The high As content was controlled mainly by the natural geological background factor, while the content of Cd reflected the difference in regional pollution caused by differing development in cities. Three surface sediment samples were evaluated as class Ⅱ of the National Marine Sediment Standard due to the content of As, while six surface sediment samples were evaluated as class Ⅱ due to the content of Cr, of which the pollution degree was moderate. The concentrations of Cd, Cu, Hg, Pb, and Zn in all of the 159 sediment samples fall in the Ⅰ class, of which the pollution degree is low. The degree of pollution for seven heavy metals were arranged in the following order:As > Cr > Pb > Zn > Cu > Cd > Hg. The potential ecological risk assessment results indicated that all heavy metals in surface sediment caused low levels of pollution generally, and that each heavy metal element was at a low ecological risk level. The order for the ecological risk of the seven heavy metals was:As > Hg > Cd > Pb > Cu > Cr > Zn; therefore, As was the main ecological risk factor. In general, the potential ecological risk for heavy metals was low, which illustrated that the marine environment in the study area was excellent.

Effects of alfalfa saponin extract on mRNA expression of Ldlr, LXRα, and FXR in BRL cells.

We studied the effects of alfalfa saponin extract (ASE) on low density lipoprotein receptor (Ldlr), liver X receptor α (LXRα), and farnesoid X receptor (FXR) in normal and hyperlipidemic Buffalo rat liver (BRL) cells. Normal and hyperlipidemic BRL cells were divided into eight groups: normal, or normal cells treated with 50, 100, and 150 mg/L ASE, hyperlipidemic, or hyperlipidemic cells treated with 50, 100, and 150 mg/L ASE. After treatment for 24 h, Ldlr, LXRα, and FXR mRNA expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Data showed that mRNA expression of Ldlr in normal BRL cells was significantly up-regulated by ASE treatment and mRNA expressions of LXRα and FXR were significantly down-regulated both in normal and hyperlipidemic BRL cells after ASE treatment. Thus, ASE might ameliorate hepatic steatosis by regulating genes involved in cholesterol metabolism, including up-regulation of Ldlr as well as down-regulation of LXRα and FXR.

Studies on electrochemical performances of novel electrolytes for wide-temperature-range lithium-ion batteries.

Wide-temperature electrochemical behaviors of sulfolane (SL) with lithium difluoro(oxalato)borate (LiODFB) are studied using dimethyl sulfite (DMS) and diethyl sulfite (DES) as mixed solvents, respectively. In LiFePO4/Li cells, LiODFB-SL/DMS and LiODFB-SL/DES electrolytes always exert several advantages over a wide temperature range, such as stable cycling performance and good rate performance. Besides, in Li/mesophase carbon microbead cells, these novel electrolytes respectively exhibit excellent film-forming characteristics at both +60 and -20 °C, such as the formation of a stable and conductive SEI layer. It suggests that LiODFB-SL/DMS and LiODFB-SL/DES electrolytes are alterative candidate electrolytes for wide-temperature-range lithium-ion batteries.