Conventional liquid electrolytes applied in lithium-ion batteries suffer from high flammability, lithium dendrites and leakage. Gel polymer electrolytes (GPEs) are promising alternative electrolytes ...owing to their high ionic conductivities and enhanced safeties. Nevertheless, the flammable plasticizers of GPEs still bring safety hazards for the batteries. To address these issues, nonflammable highly-fluorinated quasi-solid-state polymer electrolytes (ED@PVDF) with ultrahigh ionic conductivities, excellent flame-retardant properties and superior cycling stability are developed. ED@PVDF possesses three-dimensional polymeric network within the framework of electrospun PVDF fibers, which is fabricated by thiol-ene click reaction. Highly-fluorinated carbonates (fluoroethylene carbonate and methyl 2,2,2-trifluoroethyl carbonate) are employed as plasticizers for ED@PVDF to improve flame-retardant property and enhance compatibility with anodes. Nonflammable ED@PVDF exhibits remarkable flame resistance, the highest ionic conductivity (4.41 mS cm−1 at 30 °C) among the nonflammable polymer electrolytes and wide electrochemical windows (5.6 V). ED@PVDF can promote the generation of LiF-rich solid electrolyte interphase and effectively restrain dendrite growth on Li metal anodes. ED@PVDF endows LiFePO4 cells with outstanding rate capability (specific capacity of 123.8 mAh g−1 at 5C rate) and superior cycling stability (capacity retention of 81.4% over 1000 cycles).
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•A nonflammable quasi-solid-state polymer electrolytes ED@PVDF was developed.•ED@PVDF exhibits remarkable flame resistance.•ED@PVDF possesses high ionic conductivity of 4.41 mS cm−1 at 30 °C.•ED@PVDF can effectively suppress dendrite growth on Li metal anodes.•LiFePO4 cells assembled with ED@PVDF exhibit excellent performance.
In this study, the biotypes, chemical structures and porosity characteristics of hydrocarbon-generating organisms in the Wufeng Formation-Longmaxi Formation of the Well Jiaoye-1 and in the Qiongzhusi ...Formation of the Well Jinye-1, Sichuan Basin, are studied through the systematic organic petrology and geochemical analysis. The hydrocarbon-generating organisms in the Wufeng Formation-Longmaxi Formation mainly consist acritarchs and graptolites, with other animal fossils observed. The hydrocarbon-generating organisms of the Qiongzhusi Formation are mainly acritarchs, benthic macroalgae and cyanobacteria, together with some animal fossils such as embryos, sponge spicules. Besides, cryptospore fossils are found in the bottom of Qiongzhusi Formation, Fortunian of the Lower Cambrian for the first time ever. According to raman parameters, the change of pyritized acritarch and bitumen in the same thermal evolution process is greater, followed by that of organic acritarch, and the structural change of graptolite is the smallest. FTIR spectra shows ether bonds, a few aromatic rings, some aliphatic chains in the structures of acritarchs and very low content of aliphatic hydrocarbon, a large amount of carboxyl groups, ether bonds, aromatic rings in both graptolite and chitinozoan. The acritarch has well-developed pores which is of excellent connectivity. The epidermis of graptolite is composed of multiple layers of fiber, between which develop a lot of narrow pores of good connectivity. Conodont has many isolated nano-pores, while the pores of chitinozoan are not developed.
•Hydrocarbon-generating organisms in the Lower Paleozoic, Sichuan Basin are studied.•Variety kinds of hydrocarbon-generating organisms have been found.•Cryptospores are found in the Fortunian, Lower Cambrian for the first time ever.•Chemical composition and degree of thermal evolution of each organism are different.•Porosity of acritarch is well-developed.
Localized high concentration electrolytes (LHCEs) possess low viscosity, good wettability, sufficient ionic conductivity and good compatibility with lithium metal anodes. However, diluents of LHCEs ...suffer from high density, high-cost and low activity in the formation of robust SEIs. Herein, we developed a trimethyl phosphate (TMP)-based nonflammable LHCE diluted by 1,2-difluorobenzene (DFB), which lower density, lower cost, lower LUMO and better fluorine-donating property. With the addition of DFB, 3.2 M LiFSI/TMP/DFB (LiFSI/TMP/DFB 0.75:1:0.5) exhibits reduced viscosity (49.2 mPa s) and improved ionic conductivity (1.27 mS cm−1), while the local high-concentration solvation structure of TMP-Li+-FSI− is retained. DFB can fabricate LiF-rich SEI on lithium metal anodes owing to its low LUMO and fluorine donor properties, and efficiently inhibits lithium dendrites. Remarkably, the battery performance of the LHCE is significantly improved by DFB. 3.2 M LiFSI/TMP/DFB endows LiNi0.8Co0.1Mn0.1O2/Li cells with excellent long-term cycle performance (capacity retention of 80.1% after 500 cycles). LiFePO4/Li cells with 3.2 M LiFSI/TMP/DFB demonstrate high rate capability (discharge capacity of 112.7 mAh g−1 at 5 C rate) and outstanding long-term cycle performance (capacity retention of 80.9% after 850 cycles).
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•Nonflammable electrolyte 3.2 M LiFSI/TMP/DFB was developed.•Diluent DFB possesses low density, low cost and low LUMO.•Diluent DFB promotes the fabrication of LiF-rich SEIs on Li metal anodes.•3.2 M LiFSI/TMP/DFB effectively suppresses dendrite growth on Li metal anodes.•NCM811 cells with 3.2 M LiFSI/TMP/DFB exhibit enhanced cycle performance.
To explore the characteristics of C-TIRADS by comparing it with ACR-TIRADS, Kwak-TIRADS, KSThR-TIRADS and EU-TIRADS.
A total of 1096 nodules were collected from 884 patients undergoing thyroidectomy ...in our center between May 2018 and December 2020. Divided the nodules into two groups: ">10mm" and "≤10mm". Ultrasound characteristics of each nodule were observed and recorded by 2 doctors, then classified based on ACR-TIRADS, Kwak-TIRADS, KSThR-TIRADS, EU-TIRADS, and C-TIRADS.
A total of 682 benign nodules cases (62.23%) and 414 malignant nodules cases (37.77%) were identified. The ICC value of each guideline was:0.937(ACR-TIRADS), 0.858(EU-IRADS), 0.811(Kwak-TIRADS), 0.835(KTA/KSThR-TIRADS) and 0.854(C-TIRADS). The nodule malignancy rates in the groups(Kwak-TIRADS 4B, C-TIRADS 4B、4C) of two sizes were significantly different (all p<0.05). There was no statistical difference in the other grades of two sizes (all p>0.05). Unnecessary biopsy rates were the lowest in C-TIRADS (49.02% p<0.001). Furthermore, Kwak-TIRADS had the highest sensitivity and NPV (89.9%, 91.0%, all p<0.05), while C-TIRADS had the highest specificity and PPV (82.3%, 69.2%, all p<0.05). C-TIRADS and Kwak-TIRADS had the highest accuracy (76.0%, 72.5%, P=0.071). The AUCs of the 5 guidelines were C-TIRADS(0.816, P<0.05), Kwak-TIRADS(0.789, P<0.05) KTA/KSThR-TIRADS and ACR-TIRADS(0.773, 0.763, P=0.305), EU-TIRADS(0.734, P<0.05). The AUCs of the five guidelines were not statistically different between "nodules>10mm" and "nodules ≤ 10mm" (all P>0.05).
All five guides showed excellent interobserver agreement. C-TIRADS was slightly efficient than Kwak-IRADS, KTA/KSThR-TIRADS and ACR-TIRADS, and had greater advantages than EU-TIRADS. The diagnostic abilities of the five guidelines for "nodules ≤ 10mm" were not inferior to that of "nodules> 10mm". C-TIRADS is simple and easy to implement and can provide effective thyroid tumor risk stratification for thyroid nodule diagnosis, especially in China.
A novel type of poly(maleic anhydride)-graft-poly(vinyl alcohol) comb polymer functionalized magnetic nanoparticles was specially designed and prepared as an efficient adsorbent with ...stimuli-responsive reversible adsorption/desorption behavior for the controllable removal of heavy metal ions. The adsorption capacities of comb polymer functionalized magnetic nanoparticles toward Ag+, Ni2+, Cd2+, Pb2+ and Co2+, exhibiting good fits to Langmuir isotherm model and Pseudo-second order kinetic model with correlation coefficients of more than 0.98, were 0.8634, 0.8194, 0.8429, 0.6720 and 0.7682 mmol g−1 respectively, which were 5 times greater than those of linear polymer functionalized magnetic nanoparticles due to the contribution of topology evolution. Furthermore, the uptake rate of comb polymer functionalized magnetic nanoparticles toward Ag+, Ni2+, Cd2+, Pb2+ and Co2+ increased significantly from 21.1%, 17.6%, 18.64%, 16.3% and 15.68% to 92.15%, 89.2%, 90.16%, 83.56% and 84.52% respectively when the solution pH increases from 4 to 7, showing a pH-responsive characteristic, the mechanism of which was elucidated as the pH-driven changes in electrostatic interaction and molecular morphology. Good sustainability and facile reusability were practically reflected by over 80% uptake efficiency after 5 consecutive absorption/desorption cycles. The innovation of this work is that changing molecular topological structure of the polymer can significantly contribute to excellent adsorption capacity and pH responsiveness to remove heavy metal ions in wastewater. The importance of this study is to offer a practical cleaner production process for an attractive adsorbent with stimuli-responsive adsorption behavior and good sustainable application through innovative molecular design.
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•A cleaner production process for a new Fe3O4/PMA-g-PVA adsorbent is established.•Good sustainability, easy reusability and facile regeneration are actually achieved.•High adsorption efficiency is achieved by innovatively changing topological structure.•Stimuli-responsive reversible adsorption/desorption for removing heavy metal ions.•An environmental and technical feasibility for the control in wastewater treatments.
Mitophagy plays a pro-survival or pro-death role that is cellular-context- and stress-condition-dependent. In this study, we revealed that cyclovirobuxine D (CVB-D), a natural compound derived from ...Buxus microphylla, was able to provoke mitophagy in lung cancer cells. CVB-D-induced mitophagy potentiates apoptosis by promoting mitochondrial dysfunction. Mechanistically, CVB-D initiates mitophagy by enhancing the expression of the mitophagy receptor BNIP3 and strengthening its interaction with LC3 to provoke mitophagy. Our results further showed that p65, a transcriptional suppressor of BNIP3, is downregulated upon CVB-D treatment. The ectopic expression of p65 inhibits BNIP3 expression, while its knockdown significantly abolishes its transcriptional repression on BNIP3 upon CVB-D treatment. Importantly, nude mice bearing subcutaneous xenograft tumors presented retarded growth upon CVB-D treatment. Overall, we demonstrated that CVB-D treatment can provoke mitophagy and further revealed that the p65/BNIP3/LC3 axis is one potential mechanism involved in CVB-D-induced mitophagy in lung cancer cells, thus providing an effective antitumor therapeutic strategy for the treatment of lung cancer patients
A staggered-grid finite difference method is used to model seismic wave records in a coal bearing, porous medium. The variables analyzed include the order of the difference calculations, the use of a ...perfect match layer to provide absorbing boundary conditions, the source location, the stability conditions, and dispersion in the medium. The results show that the location of the first derivative of the dynamic variable with respect to space is coincident with the location of the first derivative of the kinematic varable with respect to time. Outgoing waves are effectively absorbed and reflection at the boundary is very weak when more than 20 perfect match layer cells are used. Blot theory considers the liquid phase to be homogeneous so the ratio of liquid to solid exposure of the seismic source depends upon the medium porosity. Numerical dispersion and generation of false frequencies is reduced by increasing the accuracy of the difference calculations and by reducing the grid size and time step. Temporal second order accuracy, a tenth order spatial accuracy, and a wavelength over more than ten grid points gave acceptable numerical results. Larger grid step sizes in the lateral direction and smaller grid sizes in the vertical direction allow control of dispersion when the medium is a low speed body. This provides a useful way to simulate seismic waves in a porous coal bearing medium.
Ischemic stroke is a debilitating clinical disorder that affects millions of people, yet lacks effective neuroprotective treatments. Fish oil is known to exert beneficial effects against cerebral ...ischemia. However, the underlying protective mechanisms are not fully understood. The present study tests the hypothesis that omega-3 polyunsaturated fatty acids (n-3 PUFAs) attenuate ischemic neuronal injury by activating nuclear factor E2-related factor 2 (Nrf2) and upregulating heme oxygenase-1 (HO-1) in both in vitro and in vivo models. We observed that pretreatment of rat primary neurons with docosahexaenoic acid (DHA) significantly reduced neuronal death following oxygen-glucose deprivation. This protection was associated with increased Nrf2 activation and HO-1 upregulation. Inhibition of HO-1 activity with tin protoporphyrin IX attenuated the protective effects of DHA. Further studies showed that 4-hydroxy-2E-hexenal (4-HHE), an end-product of peroxidation of n-3 PUFAs, was a more potent Nrf2 inducer than 4-hydroxy-2E-nonenal derived from n-6 PUFAs. In an in vivo setting, transgenic mice overexpressing fatty acid metabolism-1, an enzyme that converts n-6 PUFAs to n-3 PUFAs, were remarkably resistant to focal cerebral ischemia compared with their wild-type littermates. Regular mice fed with a fish oil-enhanced diet also demonstrated significant resistance to ischemia compared with mice fed with a regular diet. As expected, the protection was associated with HO-1 upregulation, Nrf2 activation, and 4-HHE generation. Together, our data demonstrate that n-3 PUFAs are highly effective in protecting the brain, and that the protective mechanisms involve Nrf2 activation and HO-1 upregulation by 4-HHE. Further investigation of n-3 PUFA neuroprotective mechanisms may accelerate the development of stroke therapies.
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