Probiotics are considered to be a potential treatment for ulcerative colitis (UC). The aim of this study was to compare the preventive effect of a space flight‐induced mutant L. reuteri F‐9‐35 and ...its wild type on UC in vivo. Female mice were randomly assigned to five groups: one normal and four colitic. Mice from colitis groups were daily gavaged with 0.2 mL 12% (w/v) skim milk containing the mutant or wild type (1 × 1011 CFU/mL), skim milk alone or distilled water for the whole experiment period, starting 7 days before colitis induction. UC was induced by administrating mice with 3.5% (w/v) dextran sulfate sodium (DSS) in drinking water for 7 days, after which DSS was removed and maintained for 3 days as a recovery phase. The results showed that the mice fed with L. reuteri F‐9‐35 had less inflammatory phenotype according to macroscopic and histological analysis, reduced myeloperoxidase activity, and lower expression of proinflammatory genes (Tumor necrosis factor‐α, cyclooxygenase‐2 and interleukin‐6) in colonic tissue compared with control. Furthermore, L. reuteri F‐9‐35 protected the mice from gut microbiota dysbiosis from DDS induced colitis. Neither wild type nor the milk alone had such beneficial effects. From above we conclude that L. reuteri F‐9‐35 has great potential in the prevention of UC as a dietary supplement.
Practical Application
Ulcerative colitis (UC) is the most common inflammatory bowel diseases and there is still a lack of safe and effective treatments. Consumption of L. reuteri F‐9‐35 may effective in preventing human UC.
Fire accidents are unpredictable, especially oil fires, which often lead to serious losses because they cannot be extinguished quickly. Accidents are unavoidable, even though it is desirable to ...prevent them with solid preventative measures. There are two approaches to the study of fire. On the one hand, it is to study the intrinsic safety of hazardous substances; on the other hand, it is to study the energy efficiency of fire extinguishing substances. While the latter tries to investigate effective control conditions, the former aims to prevent the occurrence of fires. In reality, as the most commonly used fire extinguishing carrier, water is an effective weapon for different fires. Therefore, with the purpose of environmental protection and energy conservation, the fire extinguishing effect of the water mist system under pure water and low concentration of green additives is explored. The self-made polymer composite additives and NaCl salt were compared with pure water mist system. The findings show that under this low-pressure system, 1% polymer composite additives had the best extinction efficiency enhancement, pure water under medium and high pressure was more effective, and 1% NaCl salt additive negatively correlated with the extinction efficiency.
Propane dehydrogenation (PDH) has great potential to meet the increasing global demand for propylene, but the widely used Pt‐based catalysts usually suffer from short‐term stability and ...unsatisfactory propylene selectivity. Herein, we develop a ligand‐protected direct hydrogen reduction method for encapsulating subnanometer bimetallic Pt–Zn clusters inside silicalite‐1 (S‐1) zeolite. The introduction of Zn species significantly improved the stability of the Pt clusters and gave a superhigh propylene selectivity of 99.3 % with a weight hourly space velocity (WHSV) of 3.6–54 h−1 and specific activity of propylene formation of 65.5 molC3H6
gPt−1 h−1 (WHSV=108 h−1) at 550 °C. Moreover, no obvious deactivation was observed over PtZn4@S‐1‐H catalyst even after 13000 min on stream (WHSV=3.6 h−1), affording an extremely low deactivation constant of 0.001 h−1, which is 200 times lower than that of the PtZn4/Al2O3 counterpart under the same conditions. We also show that the introduction of Cs+ ions into the zeolite can improve the regeneration stability of catalysts, and the catalytic activity kept unchanged after four continuous cycles.
A lean, mean, propylene machine: Subnanometer bimetallic Pt–Zn clusters are encapsulated inside silicalite‐1 (S‐1) zeolite via a ligand‐protected direct hydrogen reduction method. In the propane dehydrogenation (PDH) reaction, the PtZn4@S‐1‐H catalyst exhibited a very high propylene selectivity of 99.3 % and specific activity of propylene formation of 65.5 molC3H6
gPt−1 h−1 at 550 °C. Moreover, no obvious deactivation was observed over catalyst even after 13000 min on stream.
A phloroglucinol‐terpene adduct (PTA) collection consisting of twenty‐four molecules featuring three skeletons was discovered from Baeckea frutescens. Inspired by its biosynthetic hypothesis, we ...synthesized this PTA collection by reductive activation of stable phloroglucinol precursors into highly reactive ortho‐quinone methide (o‐QM) intermediates and subsequently Diels–Alder cycloaddition. We also demonstrated, for the first time, the generation process of the active o‐QM by performing dynamic NMR and HPLC‐MS monitoring experiments. Moreover, the PTA collection showed significant antifeedant effect toward the Plutella xylostella larvae.
Insight of nature: A phloroglucinol‐terpene adduct (PTA) collection was discovered from Baeckea frutescens. The plausible biogenetic pathway, biomimetic synthesis, generation mechanism, and feeding deterrent activity of the PTA collection were also investigated. The current study first provided experimental evidence to explain how, and perhaps why, plants apply a combinatorial strategy to create the PTA collection (see figure).
Polysaccharide production from the aerial parts of Plantaoo asiatica L. was carried out using water decoction. Response surface methodology (RSM), based on a five level, four variable central ...composite design (CCD), was employed to obtain the best possible combination of extraction time (X1: 1–5h), extraction temperature (X2: 60–100°C), number of extraction (X3: 1–5), and ratio of water to raw material (X4: 10–30) for maximum polysaccharide production. The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed by appropriate statistical methods (ANOVA). The optimum extraction conditions were as follows: extraction time of 3.9h, extraction temperature of 91°C, number of extraction of 4, and ratio of water to raw material of 24. Under these conditions, the experimental yield was 4.37±0.13%, which is well in close agreement with value predicted by the model.
Diallyl phthalate (DAP), a crucial raw material in producing resin materials, has been studied widely in terms of its polymerization process and application in material modification. However, less ...attention has been paid to its safety. In this study, the influence of initiators on the thermal hazard of DAP was examined from various viewpoints by conducting thermogravimetric and differential scanning calorimetry experiments and by performing thermokinetic analysis with multiple models. Moreover, the reaction mechanism of DAP was studied. The three-step autocatalysis reaction simulations agreed well with the experimental findings obtained for DAP. The simulated conversion limit time and time to the maximum rate under adiabatic conditions indicate that the thermal hazard of DAP can serve as a reference for controlling its production and storage temperatures.
The effects of two different metal oxide catalysts, SnO and Li2O, on the dehydrogenation temperature of Carbazole and N-Ethylcarbazole (NE), respectively, were investigated by the Thermogravimetric ...analyzer and Differential Scanning Calorimetry. Thermogravimetric experiments were performed with 10wt% SnO and Li2O added to Carbazole and N-Ethylcarbazole, respectively, and compared to pure Carbazole and N-Ethylcarbazole. The results showed that the dehydrogenation temperature of N-Ethylcarbazole was lower than that of Carbazole, and the dehydrogenation temperature of N-Ethylcarbazole +SnO was the lowest, and SnO is an ideal dehydrogenation catalyst for N-Ethylcarbazole. Experiments using Differential Scanning Calorimetry and a Thermogravimetric analyzer showed that with the addition of catalyst, the activation energy of the mixture was more significant and stable, and the thermal hazard was reduced, whereas the relative dehydrogenation temperature was increased. This study provides important information for improving the design of dehydrogenation catalysts for organic liquid hydrogen storage processes.
In recent years, the prosperous electric vehicle industry has contributed to the rapid development of lithium-ion batteries. However, the increase in the energy density of lithium-ion batteries has ...also created more pressing safety concerns. The emergence of a new flame-retardant material with the additive ethoxy (pentafluoro) cyclotriphosphazene can ameliorate the performance of lithium-ion batteries while ensuring their safety. The present study proposes a new polymer composite flame-retardant electrolyte and adopts differential scanning calorimetry (DSC) and accelerating rate calorimetry to investigate its thermal effect. The study found that the heating rate is positively correlated with the onset temperature, peak temperature, and endset temperature of the endothermic peak. The flame-retardant modified polymer electrolyte for new lithium-ion batteries has better thermal stability than traditional lithium-ion battery electrolytes. Three non-isothermal methods (Kissinger; Kissinger–Akahira–Sunose; and Flynn–Wall–Ozawa) were also used to calculate the kinetic parameters based on the DSC experimental data. The apparent activation energy results of the three non-isothermal methods were averaged as 54.16 kJ/mol. The research results can provide valuable references for the selection and preparation of flame-retardant additives in lithium-ion batteries.
The compatibility of lithium metal with organic solvents is the most crucial for lithium metal batteries (LMBs). Even though ether solvents show excellent compatibility toward lithium metal, the ...reactivity of the ether solvents at elevated temperatures and high voltages hinders their utilization in lithium metal battery systems. In this study, a high‐temperature ether electrolyte is designed comprising lithium oxalyldifluoroborate (LiODFB), diethylene glycol dibutyl ether (DGDE), 3‐methoxypropionitrile (MPN), and fluorinated ethylene carbonate (FEC), which is abbreviated as MDF electrolyte. The presence of MPN in the electrolyte changes the solvation structure, thereby facilitating increased redox reactions of ODFB− and synergizing with FEC to build a robust solid electrolyte interface (SEI), effectively inhibiting lithium dendrites growth and solvent decomposition. Consequently, the MDF electrolyte exhibits not only long cyclic stability and high coulombic efficiency in Li||Cu and Li||Li cells but also excellent cyclic characteristics in both Li||LiFePO4 (LFP) and Li||LiNi0.8Co0.1Mn0.1O2 (NCM811) cells. Remarkably, these cells demonstrate stable operation even when exposed to higher temperatures of up to 80 °C, while the Li||NCM811 cell maintains consistent cyclic stability at an elevated voltage level of 4.5 V.
A versatile electrolyte system is established to expand the work temperature window simple using 3‐methoxypropionitrile (MPN) as a co‐solvent to the conventional diethylene glycol dibutyl ether (DGDE) solvent, which manipulates the decomposition of DGDE and lithium salts. Particularly, it works with various lithium secondary batteries including Li||LiFePO4 (LFP) and Li||LiNi0.8Co0.1Mn0.1O2 (NCM811), which exhibit exceptional electrochemical performance at high temperatures.
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