626 results on '"Huo, Feng"'
Search Results
302. Interfacial layering and orientation ordering of ionic liquid around single-walled carbon nanotube: a molecular dynamics study.
- Author
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Huo, Feng and Liu, Zhiping
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SINGLE walled carbon nanotubes , *IONIC liquids , *MOLECULAR dynamics , *TETRAFLUOROBORATES , *MOLECULAR structure , *CRYSTAL orientation - Abstract
Single-walled carbon nanotubes (SWNTs) tend to aggregate to heavily tangled bundles due to the strong van der Waals attraction. Ionic liquids (ILs) are a kind of newly proposed solvents in which SWNT can be physically well dispersed. In this article, the cylindrical interface has been investigated by molecular dynamics simulation between IL of 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) and an infinite long armchair (6,6) SWNT. The highly ordered structure of the cations and anions is elucidated by the simulation results. Two evident dense layers are found for both the cations and anions along the surface normal direction of the SWNT. In addition, we have observed two different orientation patterns of the cations in the first layer. In sublayer 1A, which is the nearest to the surface, the imidazolium rings of the cations prefer to be parallel to the surface, with a slight tilt angle less than 15°. In sublayer 1B, they tend to be perpendicular to the surface, with their butyl chains appearing in sublayer 1A. The [BF4]− anions are found to cling to the nanotube surface with three fluoride atoms, also indicating a highly ordered orientation. The simulation results in this work provide a clue to understand the stabilisation and dispersion of SWNT bundles in ILs. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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303. Constructing stable lithium interfaces via coordination of fluorinated ether and liquid crystal for room-temperature solid-state lithium metal batteries.
- Author
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Li, Jin, Huo, Feng, Yang, Yaxi, Chen, Tianhua, Cui, Yingyue, Cai, Yingjun, and Zhang, Haitao
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- *
LIQUID crystals , *LITHIUM cells , *SOLID state batteries , *LITHIUM cell electrodes , *ELECTROFORMING , *ELECTRIC batteries , *IONIC conductivity - Abstract
[Display omitted] • Fluorinated ether and liquid crystal were used to form compatible interface. • Regulated stable lithium interfaces were realized via free radical graft. • Optimized SSEs exhibits superior ionic conductivity and robust mechanical strength. • Room-temperature SSLMBs show excellent electrochemical performance. The poor compatibility of the electrodes/solid-state electrolytes (SSEs) interfaces of rechargeable room-temperature solid-state lithium metal batteries (RTSSLMBs) limit their rapid development and commercialization. Herein, fluorinated ether as a block and liquid crystal 4,4′'-Azoxyanisole as an additive are firstly used to fabricate robust SSEs for RTSSLMBs. A combination of in-situ polymerization and the construction of stable interfaces is employed to obtain excellent cycling performance in LMBs. We propose the mechanism of regulating the lithium anode interfaces by 4,4′'-Azoxyanisole with high anchoring strength in SSEs. Liquid crystal with high anchoring strength ensures the smooth electrodeposition of lithium metal, and fluorinated ether provides rich LiF for SEI, which is beneficial to inhibit the growth of lithium dendrite. The electrochemical test shows that symmetrical lithium batteries maintain steadily operation over 3500 h. Further, the novel 3D fiber-network SPEs exhibit high ionic conductivity of 0.13 mS/cm at room temperature, a wide electrochemical stability window of 4.9 V, a high lithium-ion transference number of 0.42, and better mechanical strength (Young's modulus of 6.3 GPa). As a consequence, superior cycling stability is demonstraced in Li/LiFePO 4 batteries at ambient temperature. In addition, the reaction mechanism is verified by density functional theory calculations and various electrochemical characterizations. This new and universal strategy may be a new route to suppress Li dendrites, it will be helpful for the commercialization and application of RTSSLMBs. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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304. Unilamellar Vesicle Formation and Microscopic Structure of Ionic Liquids in Aqueous Solutions
- Author
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Liu, Xiaomin, Zhou, Guohui, Huo, Feng, Wang, Jianji, and Zhang, Suojiang
- Abstract
Imidazolium-based ionic liquid [Cnmim]Br (n= 10, 12, 14) without any additives in aqueous solutions could form unilamellar vesicles was first observed by TEM recently. As molecular aggregation is a complex phenomenon which is difficult to study in detail experimentally, we performed molecular simulations for [Cnmim]Br (n= 10, 12, 14) aqueous solutions. The entire process of spontaneous aggregation for [C12mim]Br into small unilamellar vesicle was elucidated. Radial distribution functions reveal that the strong spatial correlation between cation and anion still exists in the presence of a large amount of water. The inner layer of vesicle is packed denser than the outer layer by analyzing the radial density distribution. Furthermore, anions distribution provides the direct evidence for very little anions being dissolved in the water and verifies the experimental speculation. By analyzing hydrogen bond number and coordination number in the solution, it is implied that binding between counterions enhanced with increasing IL concentration, and the distribution density of ions in vesicle is close to the neat system. Moreover, it is observed that aggregation is facilitated with increasing the alkyl chains by comparing three aqueous solution systems. Additionally, spatial correlation between chain terminal C becomes stronger with increasing the alkyl chain length.
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- 2016
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305. Studies on Character of a Chitinase ChiC from Aeromonas veronii B565 and its Synergism with Chitin Binding Protein.
- Author
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HUO Feng-min, YANG Ya-lin, XU Li, ZHANG Mei-chao, HE Su-xu, and ZHOU Zhi-gang
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CHITINASE ,METHANOL ,AEROMONAS ,CHITIN ,CARRIER proteins - Abstract
To investigate the characteristics of low activity ChiC from A. veronii B565 and break the bottleneck of its application, this experiment established a recombined ChiC pichia engineering bacteria GS115/PIC9-ChiC, carried out methanol induction expression and purification, and studied its basic enzymology properties. The result indicated that ChiC was expressed in P. pastoris with a yield of 232.6 mg/L after 48 h methanol induction. The purified ChiC showed optimal specific activity of 7.6 U/mg at pH 8.0 and 40°C. ChiC had broad adaptability for pH and temperature. It retained over 80% optimal activity at pH 3.0~10.0 at 40°C or the temperature 0~40°C at pH 7.0. The chitin binding protein CBP21 from Serratia marcescens GIM1.217 was expressed in E. Coli. The affinity of CBP21 for shrimp shell chitin and colloidal chitin were different, the chitinase activity of ChiC was increased significantly from 2 (colloidal chitin as substrate) to 9 (shrimp shell chitin as substrate) fold, when acted synergistically with CBP21. This study laid a theoretical foundation for further slurrying chitinase gene, and provided a possible solution for breaking the bottleneck of this low enzyme activity of chitinase application. [ABSTRACT FROM AUTHOR]
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- 2014
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306. P2.21: Protection of Normal Metabolic Function of Healthy Pig Livers Following Prolonged Normothermic Ex-situ Perfusion
- Author
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Llorens, Jordi Vengohechea, Muñoz, Javier, He, Xiran, Liang, Mingju, Sanahuja, Josep Maria, Vendrell, Marina, León, Felipe, Albiol, Joaquim, Lin, Li, Tan, Xiaoyu, Huo, Feng, Hessheimer, Amelia Judith, and Fondevila, Constantino
- Published
- 2022
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307. Organic Selenocyanates: Rapid Advancements and Applicationsin the Field of Organic Chemistry
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Karmaker, Pran Gopal and Huo, Feng
- Abstract
The incorporation of the cyanato‐chalcogen group (OCN, SCN, and SeCN) has piqued the interest of many researchers in the field of modern organic synthetic chemistry. Methodologies for selenocyanation are far less advanced than those for OCN and SCN chemistry due to the scarcity of SeCN transfer reagents and synthetic approaches. It has also been discovered that the selenocyanate precursor (SeCN) performs significantly better than the thiocyanate (SCN) precursor in terms of pharmacological properties of organic scaffolds. Recent years, new reagents (nucleophilic, electrophilic, radical) and techniques were introduced that allowed the creation of the selenocyanato group uncomplicatedly under gentle reaction conditions, particularly in transition metal catalysis and photo‐/electro‐chemically influenced reactions, which were seemingly unimaginable. In this review, we have categorized a variety of techniques using various types of selenocyanate regents and their applications in the last decades, focusing on multiple catalysts for the preparation of organic selenocyanates and their derivatives. Methodologies for selenocyanationare far less advanced than those for OCN and SCN chemistry due to the scarcity of SeCN transfer reagents and synthetic approaches. In recent years, new reagents (nucleophilic, electrophilic, radical) and techniques were introduced that allowed the creation of the selenocyanato group uncomplicatedly under gentle reaction conditions. In this review, we have categorized a variety of techniques using various types of selenocyanate reagents and their applications in the last decades, focusing on multiple catalysts for the preparation of organic selenocyanates and their derivatives.
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- 2022
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308. Precision contouring control of machine tools.
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Huo, Feng and Poo, Aun-Neow
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NUMERICAL control of machine tools , *MACHINING , *MOTION control devices , *ELECTRONIC control , *MANUFACTURING processes - Abstract
Computer numerical control (CNC) machines are now widely used in the manufacturing industry. There is an increasing need for lower-costing machines capable of high precision machining. To achieve high precision machining, the motions of the axes of these machine tools need to be controlled precisely so that they follow a desired path, or contour, accurately. This paper discusses some of the factors that can affect the accuracy of the contour generated. Also discussed are some compensation approaches to compensating the geometrical errors of these machines so as to achieve precision results even with not-so-accurately build machines. Also presented and discussed are the results of approaches taken in improving contouring accuracy through the design and tuning of the machine axis controllers as well as some contour path compensation approaches. [ABSTRACT FROM AUTHOR]
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- 2013
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309. Sensitivity enhancement of fluorescence detection in CE by coupling and conducting excitation light with tapered optical fiber.
- Author
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Yang, Xiupei, Huo, Feng, Yuan, Hongyan, Zhang, Bo, Xiao, Dan, and Choi, Martin M. F.
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- 2011
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310. Pollution Flashover Characteristics of Composite Crossarm Insulator with a Large Diameter.
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Nan, Jing, Li, Hua, Wan, Xiaodong, Huo, Feng, and Lin, Fuchang
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COMPOSITE insulators ,FLASHOVER ,POLLUTION ,SILICONE rubber ,HYDROPHILIC surfaces ,STRUCTURAL optimization - Abstract
The composite crossarm insulator differs greatly from the suspension insulator in structure and arrangement. This study aims to determine the pollution flashover characteristics of composite crossarm insulators under different voltage grades. Four types of AC composite crossarm insulators with diameters ranging from 100 mm to 450 mm are subjected to artificial pollution test, and then the effects of the surface hydrophobicity state of silicone rubber, core diameter, umbrella structure, arrangement, and insulation distance on the pollution flashover voltage of the composite crossarm insulators are analyzed. Under the pollution grade 0.2/1.0 mg/cm
2 and voltage grade from 66 kV to 1000 kV, if the silicone rubber surface changes from HC5 to HC6, the pollution flashover voltage of the composite crossarm insulator will increase by 13.5% to 21.0% compared with the hydrophilic surface. If the core diameter changes from 100 mm to 300 mm, the pollution flashover voltage gradient decreases with the increase in core diameter; if the core diameter changes from 300 mm to 450 mm, the pollution flashover voltage gradient increases with core diameter. Under the same insulation height and core diameter, the umbrella structure will have a certain impact on pollution flashover voltage by up to 1.7% to 5.4%. Under the horizontal arrangement, the pollution flashover voltage can increase by 10.5% to 12.1% compared with that under the vertical arrangement. Under the hydrophilic surface and weak hydrophobicity state, the pollution flashover voltage has a linear relationship with the insulation distance. The above results can provide a reference for the structural design and optimization of the composite crossarm insulator. [ABSTRACT FROM AUTHOR]- Published
- 2021
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311. Ultralow Friction and High Robustness of Monolayer Ionic Liquids
- Author
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Lu, Yumiao, Wang, Yanlei, Huo, Feng, Chen, Wei, Ma, Ming, Ding, Wei-Lu, He, Hongyan, and Zhang, Suojiang
- Abstract
Ultralow friction between interacting surfaces in relative motion is of vital importance in many pure and applied sciences. We found that surfaces bearing ordered monolayer ionic liquids (ILs) can have friction coefficient μ values as low as 0.001 at pressures up to 78 MPa and exhibit good structure recoverability. This extreme lubrication is attributed primarily to the ordered striped structure driven by the “atomic-locking” effect between carbon atoms on the alkyl chain of ILs and graphite. The longer alkyl chain has lower μ values, and the stripe periodicity is decisive in reducing energy dissipation during the sliding process. In combination with simulation, the alternate atomic-scale ordered and disordered ionic regions were recognized, whose ratio fundamentally determines the μ values and lubrication mechanism. This finding is an important step toward the practical utilization of ILs with negligible vapor pressure as superlubricating materials in future technological applications operating under extreme conditions.
- Published
- 2022
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312. Dual-Color 2D Lead–Organic Framework with Two-Fold Interlocking Structures for the Detection of Nitrofuran Antibiotics and 2,6-Dichloro-4-nitroaniline
- Author
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Liu, Yuhang, Zhang, Yi, Karmaker, Pran Gopal, Tang, Yuting, Zhang, Lilei, Huo, Feng, Wang, Ya, and Yang, Xiupei
- Abstract
The misuse of organic pollutants such as nitrofuran antibiotics (NFAs) and 2,6-dichloro-4-nitroaniline (DCN) has become a hot topic of global concern, and developing rapid, efficient, and accurate techniques for detecting NFAs and pesticides in water is a major challenge. Here, we designed a novel lead-based anion 2D metal–organic framework (MOF){[(CH3)2NH2]2[Pb(TCBPE)(H2O)2]}n(F3) with interlocking structures, in which TCBPE stands for 1,1,2,2-tetra(4-carboxylbiphenyl)ethylene. Powder X-ray diffraction and thermogravimetric analysis revealed that F3has excellent chemical and solvent stability. It is worth noting that F3has a grinding discoloration effect. The solvent-protected grinding approach achieved F3Bwith a high quantum yield (QY = 73.77%) and blue fluorescence, while the direct grinding method produced F3Ywith a high quantum yield (QY = 37.27%) and yellow–green fluorescence. Importantly, F3Bcan detect NFAs in water rapidly and sensitively while remaining unaffected by other antibiotics. F3Ycan identify DCN in water quickly and selectively while remaining unchanged by other pesticides. F3Bdemonstrated high selectivity and rapid response to NFAs at a limit of detection (LOD) as low as 0.26 μM, while F3Yindicated high selectivity and responded quickly to DCN in water at an LOD as low as 0.14 μM. The method was successfully applied to detect NFAs in actual water samples of the fish tanks and ponds as well as the pesticide DCN in soil samples. The recovery rates were 97.0–105.15% and 102.2–106.48%, and the relative standard deviations were 0.63–1.45% and 0.29–1.69%, respectively. In addition, F3Band F3Ycan be made into fluorescent test papers for the visual detection of NFAs and DCN, respectively. Combined with experiments and density functional theory calculations, the mechanism of fluorescence quenching of MOFs by target analytes was also revealed.
- Published
- 2022
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313. Nanothermometer with Temperature Induced Reversible Emission for Evaluation of Intracellular Thermal Dynamics
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Yin, Nana, Lin, Bo, Huo, Feng, Shu, Yang, and Wang, Jianhua
- Abstract
Temperature dynamics reflect the physiological state of cells, and accurate measurement of intracellular temperature helps to understand the biological processes. Herein, we report a novel nanothermometer by conjugating a fluorescent probe 3-ethyl-2-[4-(1,2,2-triphenylvinyl)styryl]benzothiazol-3-ium iodide (TPEBT) with a thermoresponsive polymer poly(N-isopropylacrylamide-co-tetrabutylphosphonium styrenesulfonate) [P(NIPAM-co-TPSS)]. The derived nanoprobe TPEBT-P(NIPAM-co-TPSS) self-assembles into micelles with TPEBT as hydrophobic core and PNIPAM as hydrophilic shell. It exhibits aggregation-induced emission (AIE) at λex/λem= 420/640 nm in aqueous medium with a quantum yield of ΦF11.9%. The rise in temperature transforms PNIPAM chains from linear to compact spheres to serve as the core of micelles, and meanwhile converts TPEBT from the state of aggregation to dispersion and redistributes in the micellar shell. Temperature-driven phase transition of P(NIPAM-co-TPSS) mediates the reversible aggregation and disaggregation of TPEBT and endows the nanothermometer with temperature-dependent AIE features and favorable sensitivity for temperature sensing in 32–40 °C. TPEBT-P(NIPAM-co-TPSS) is taken up by HeLa cells to distribute mainly in lysosomes. It enables quantitative visualization of in situ thermal dynamics in response to stimuli from carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone, oligomycin, genipin, and lipopolysaccharide. The real-time monitoring of photothermal-induced intracellular temperature variation is further conducted.
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- 2022
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314. The Research on the Improved CMG Tool for Al2O3 Ceramic
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Dai, Heng Zhen, Jin, Zhu Ji, Gao, Shang, Tao, Zhan Chun, and Huo, Feng Wei
- Abstract
A new D/SiO2 CMG tool for Al2O3 ceramic process was developed by adding some diamond abrasive into SiO2 CMG tool. The solid state reaction between the CMG tool and Al2O3 ceramic played a key role for achieving ultra-precision, high efficiency and low damage.Three kinds of formulations for the D/SiO2 tool were tested and evaluated. The material removal rate(MRR) of Al2O3 ceramic mainly depended on the content of diamond abrasive. In contrast with the corresponding SiO2 tool,the D/ SiO2 tool, which had minimal content of diamond abrasive,could achieve a minimal Ra and better MRR. The enhanced mechanical removal action made the MRR improve nearly twice times, and the process surface roughness of Al2O3 ceramic specimen using the D/ SiO2 tool kept almost same value as using the SiO2 tool without surface damage. Thus the D/ SiO2 tool is more suitable for process of Al2O3 ceramic workpieces.
- Published
- 2011
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315. Protic ionic liquids with low viscosity for efficient and reversible capture of carbon dioxide.
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Li, Fangfang, Bai, Yinge, Zeng, Shaojuan, Liang, Xiaodong, Wang, Hui, Huo, Feng, and Zhang, Xiangping
- Subjects
VISCOSITY ,CARBON dioxide ,IONIC liquids ,PARTIAL pressure ,WATER pressure ,IMIDAZOLES ,SOLVENT analysis - Abstract
• Three low viscous protic ionic liquids were synthesized for CO 2 absorption. • The ionic liquids with larger basicity show higher CO 2 absorption capacity. • Addition of H 2 O influences greatly the CO 2 absorption performance of [TMGH][Im]. • Different products were obtained in [TMGH][Im] and [TMGH][Im]-H 2 O systems. Protic ionic liquids (PILs) are considered as potential solvents for CO 2 capture due to their simple synthetic routes and unique properties. In this work, three low viscous PILs, tetramethylgunidinium imidazole ([TMGH][Im]), tetramethylgunidinium pyrrole ([TMGH][Pyrr]) and tetramethylgunidinium phenol ([TMGH][PhO]) were synthesized and the effect of anions, temperature, CO 2 partial pressure and water content on CO 2 absorption performance of PILs was also systematically studied. It was found that the PILs with larger basicity show higher CO 2 absorption capacity, and [TMGH][Im] simultaneously shows relatively high absorption rate and CO 2 absorption capacity of 0.154 g CO 2 /g IL at 40 °C, 1 bar. The addition of H 2 O has a positive effect on gravimetric absorption capacity of CO 2 at the range of 0–20 wt% H 2 O, and the highest capacity of 0.186 g CO 2 /g IL was achieved as the water content was 7 wt%. In situ FTIR,
13 C NMR and theoretical calculations verified that more stable bicarbonate are produced during CO 2 absorption by [TMGH][Im]-H 2 O system. However, neat [TMGH][Im] can react with CO 2 to form the reversible carbamate, leading to excellent recyclability after four absorption-desorption cycles. The results implied that neat [TMGH][Im] shows great potentials in CO 2 absorption applications. [ABSTRACT FROM AUTHOR]- Published
- 2019
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316. The Role of High‐Entropy Materials in Lithium‐Based Rechargeable Batteries.
- Author
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Guo, Rongnan, Yang, Yi, Zhao, Chongchong, Huo, Feng, Xue, Jiaojiao, He, Jinhai, Sun, Bowen, Sun, Zixu, Liu, Hua Kun, and Dou, Shi Xue
- Subjects
- *
STORAGE batteries , *LITHIUM sulfur batteries , *LITHIUM cells , *IONIC conductivity , *LITHIUM-ion batteries , *ENERGY density , *CHEMICAL kinetics - Abstract
The low energy density, safety concerns, and high cost associated with conventional lithium‐ion batteries pose challenges in meeting the growing demands of emerging applications. While lithiumsulfur batteries (LSBs) offer high specific capacity, their commercial viability is hindered by the prevalent issue of shuttle effects. Furthermore, the potential of solid‐state lithium batteries is constrained by the suboptimal ionic conductivity and significant interphase problems. High‐entropy materials (HEMs) have emerged as a strategic approach for the development of innovative materials possessing exceptional properties. In recent times, some studies have been undertaken to explore the potential of HEMs in lithium‐based rechargeable batteries, showcasing their favorable characteristics. This work provides a comprehensive overview of the impact of various factors associated with HEM materials, encompassing elements, structure, and morphology, on the reversibility of reactions and cycling stability. This work also presents an analysis of the effects of elements and morphology on the properties of HEMs in LSBs, which can trap soluble lithium polysulfides and enhance reaction kinetics. Additionally, the work provides an overview of high‐entropy electrolytes, including both solid‐state and non‐aqueous liquid electrolytes. Furthermore, the research outlines future research directions aimed at investigating more efficient HEMs and enhancing the overall performance of lithium‐based rechargeable batteries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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317. Prediction of the Liquid–Liquid Extraction Properties of Imidazolium-Based Ionic Liquids for the Extraction of Aromatics from Aliphatics
- Author
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Yu, Tianhao, Olsson, Emilia, Lian, Guoping, Liu, Lei, Huo, Feng, Zhang, Xiangping, and Cai, Qiong
- Abstract
Liquid–liquid extraction (LLE) is an important technique to separate aromatics from aliphatics since these compounds have very similar boiling points and cannot be separated by distillation. Ionic liquids (ILs) are considered as potential extractants to extract aromatics from aliphatics. In this paper, molecular dynamics (MD) simulations were used to predict the extraction property (i.e., capacity and selectivity) of ILs for the LLE of aromatics from aliphatics. The extraction properties of seven different ILs including [C2mim][Tf2N], [C2mim][TFO], [C2mim][SCN], [C2mim][DCA], [C2mim][TCM], [C4mim][Tf2N], and [C8mim][Tf2N] were investigated. Results show that ILs with shorter alkyl chain cations and [Tf2N]−anion exhibit better extraction efficiency than other ILs, which is in agreement with previously reported experimental data on the extraction of toluene from aliphatics and further validated the reliability of the proposed model. The binding energies between ILs and organic molecules were calculated by the density functional theory, which help explain the different extraction behaviors of different ILs. The symmetry-adapted perturbation theory analysis was performed to further understand the interaction mechanisms between ILs and organics. Our study shows that the [Tf2N]−anion also has the best extraction capability for heavier aromatics (o-xylene, m-xylene, and p-xylene) from common aliphatics (heptane and octane). The MD modeling approach can be a low-cost in silico tool for the high-throughput fast screening of ILs for the LLE of aromatics from aliphatics.
- Published
- 2021
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318. Nontraditional Luminescent Molecular Aggregates Encapsulated by Wormlike Silica Nanoparticles for Latent Fingerprint Detection
- Author
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Xu, Xin, He, Fei, Yan, Hanwen, Huo, Feng, Dong, Hongxing, Liu, Lijia, Zhang, Chunhong, and Zhao, Fangbo
- Abstract
The phenomenon of nontraditional luminescence has attracted wide attention and curiosity of researchers due to its inexplicable photoluminescence paradigm without aromatic or extended π-systems. The present work puts forward a neotype of a light-emitting nitrogenous small molecule, namely, N-stearoyl-hydroxyproline (L-C16-Hyp), which could emit weak light in aggregation states through the restriction mechanism of intramolecular motion, exhibiting properties comparable to those of AIEgens. Using these molecular aggregates as anionic surfactant micelles to incorporate within the silica matrix, we prepared fluorescent nanoparticles (FL-NPs) by a one-pot method for expedient visualization of latent fingerprints (LFPs). The FL-NPs exhibit an excitation range from 335 to 365 nm, resulting in nontraditional luminescence observed between 410 and 440 nm. The enhanced luminescent FL-NPs may derive from the collective entities or assemblies of restricted L-C16-Hyp, which can be reasonably explicated by an effect termed as cluster-triggered emission (CTE). Theoretical calculations demonstrated that this luminescence pattern belongs to partial charge transfer, which is mainly attributed to the close interaction between the tertiary amino and adjacent carboxyl in the L-C16-Hyp structure. Moreover, some merits of FL-NPs, such as wormlike nanomorphology, stable photophysical properties, low toxicity, great adhesion to multiple substrates, easy to get raw material, an inexpensive, simple process, and rapid detection without any further modification or assistance, provide the feasibility of efficacious LFP detection. Overall, this study will provide insights into the design and application of luminescent materials with unconventional groups.
- Published
- 2021
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319. Ratiometric fluorescence sensor based on europium-organic frameworks for selective and quantitative detection of cerium ions.
- Author
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Wang, Yaohui, Zheng, Yi, Huo, Feng, Zhang, Qian, Yang, Xiupei, and Karmaker, Pran Gopal
- Subjects
- *
CHEMORECEPTORS , *CERIUM , *FLUORESCENCE , *METAL-organic frameworks , *PHOTOINDUCED electron transfer , *X-ray powder diffraction , *FILTERS & filtration - Abstract
Due to the unavoidable use of cerium in daily life, the accumulation of cerium in the environment increases health risks for humans. Therefore, it is crucial to develop a chemical sensing technology for the rapid, sensitive, and selective detection of cerium ions. In this research work, a novel two-dimensional chain structure of a europium-based metal organic framework (Eu-MOF) [Eu 2 (tcpa)(Htcpa) 2 ] was synthesized by using 3,4,5,6-tetrachloro-1,2-benzenedicarboxylic acid (H 2 TCPA) as the ligand and europium nitrate as the metal source. The results of powder X-ray diffraction and thermogravimetric analysis show that the synthesized Eu-MOF has excellent chemical and thermal stability. When the Eu-MOF suspension was excited by ultraviolet light at 292 nm, four fluorescence emissions were observed at 420, 595, 620 and 705 nm. It was particularly interesting that when cerium ions (Ce3+/Ce4+) were added to the Eu-MOF suspension, the fluorescence intensity at 420 nm was enhanced, while the fluorescence at 620 nm was quenched. On this basis, a ratiometric fluorescent sensor for detecting cerium ions was constructed, which has a good linear relationship in the range of 0.05–15 μM and a detection limit of 16 nM. The plausible mechanism of the change in the fluorescence characteristics of Eu-MOF caused by cerium ions was discussed in detail. Through the study of fluorescence lifetime and ultraviolet absorption, it was proven that the mechanism of Ce3+-quenching Eu-MOF fluorescence is the inner filter effect. Photoinduced electron transfer and internal filtering effects lead to fluorescence quenching at 620 nm, while redox reactions lead to fluorescence enhancement of the ligand at 420 nm. The proposed ratiometric fluorescence sensor was successfully employed for the detection of cerium ions in real water samples, confirming that it can be used as an alternative method for the detection of Ce3+ and Ce4+ in environmental samples. [Display omitted] • A two-dimensional chain structure of europium-based metal organic framework (Eu-MOF) [Eu 2 (tcpa)(Htcpa) 2 ] was synthesized. • Eu-MOF has excellent chemical and thermal stability. • Based on the fluorescence change of Eu-MOF, a ratiometric fluorescence sensor for Ce3+/Ce4+ was constructed. • The interaction between Eu-MOF and Ce3+/Ce4+ and its fluorescence enhancement mechanism were discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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320. Recent Advances in Multifunctional Binders for High Sulfur Loading Lithium‐Sulfur Batteries.
- Author
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Guo, Rongnan, Yang, Yi, Huang, Xiang Long, Zhao, Chongchong, Hu, Binbin, Huo, Feng, Liu, Hua Kun, Sun, Bowen, Sun, Zixu, and Dou, Shi Xue
- Subjects
- *
LITHIUM sulfur batteries , *SULFUR , *IONIC conductivity , *ENERGY density , *ENERGY storage - Abstract
Lithium‐sulfur batteries (LSBs) are regarded as a highly promising next‐generation energy storage technology due to their exceptional theoretical capacity and energy density. However, the practical application of these batteries is hindered by several challenges, including significant volume change of active materials, severe shuttle effect of lithium polysulfides, inadequate electronic and ionic conductivity, and safety concerns. These issues are particularly pronounced in cathodes with high sulfur loading, which are essential for the effective implementation of LSBs. Binders are an essential constituent of sulfur cathodes, and they perform a crucial function in enhancing the efficacy of LSBs, particularly when subjected to high sulfur loading. A considerable amount of research has been conducted to investigate the potential of multifunctional binders to tackle the aforementioned challenges associated with LSBs. This article provides a comprehensive overview of the various roles that advanced multifunctional binders play in LSBs, including but not limited to preserving electrode integrity, capturing lithium polysulfides, regulating Li2S deposition, accelerating reaction kinetics, enhancing ionic and electronic conductivity, promoting sulfur cathode safety, and safeguarding the environment. Additionally, the paper outlines the challenges and prospects for future research endeavors aimed at creating innovative multifunctional binders and improving the overall performance of LSBs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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321. Viscosity calculation of 1‑ethyl‑3‑methyl‑imidazolium chloride ionic liquids based on three-body potential hydrogen bond model.
- Author
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Jiang, Kun, Liu, Xiaomin, Huo, Feng, Dong, Kun, Zhang, Xiaochun, and Yao, Xiaoqian
- Subjects
- *
VISCOSITY , *IONIC liquids , *HYDROGEN bonding , *THREE-body problem , *CHEMICAL potential - Abstract
Abstract In this study, we have developed an all-atom force field with three-body hydrogen bond model for 1‑ethyl‑3‑methyl‑imidazolium chloride ([Emim][Cl]), predicted the experimental dynamic viscosity successfully and calculated the relationship between dynamic properties and ion pair (IP) structures relaxation time. The partial atom charges and parameters of Lennard-Jones and hydrogen bond model are derived from ab initio molecular dynamic (AIMD) simulations. The strategy is that charges are fitted by AIMD structures and parameters are adjusted to make structure consistent between molecular dynamic (MD) and AIMD. The dynamic viscosities were calculated by Green-Kubo (GK) relation and were in excellent agreement with experiments results. Structure of ionic liquids was studied by using several distribution functions and IP time response was calculated. The calculated IP lifetime was found in linear correlation with viscosity and self-dynamic coefficient. Highlights • Hydrogen bond model improves simulation structures and properties calculation. • Atom charges were assigned by fitting electric density of the multi ion pairs. • Reliable sheer viscosities of ILs were computed by Green-Kubo relations. • Transport properties are related to ion pair's lifetime. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
322. Fungi residue derived carbon as highly efficient hydrogen peroxide electrocatalyst.
- Author
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Meng, Zhu, Li, Juntao, Huo, Feng, Huang, Yan, and Xiang, Zhonghua
- Subjects
- *
HYDROGEN peroxide , *ELECTROCATALYSTS , *ELECTROCHEMICAL apparatus , *OXYGEN reduction , *CARBON electrodes - Abstract
In electrochemical devices, the reduction of dissolved oxygen in electrolyte can achieve on-site production of hydrogen peroxide. The industrial viability of the process strongly depends on cathode electrocatalyst. However, current catalysts rely on rare, noble metals and their composite. Thus, it remains a great challenge of cost-effective catalyst with both high activity and selectivity. Herein, we made use of extremely low-cost fungi residue biomass, developing a multi-non-precious metal doped carbon catalyst (named as FRC) for H 2 O 2 electrogeneration by facile in-situ synthesis. The one-step prepared FRC balances the performance of different metal oxides and exhibits not only high activity but also high selectivity at a spacious potential range. Specifically, the current density for ring reaches 0.45 mA cm −2 at −0.5 V (vs SCE). Besides, the selectivity achieves 98% and remain above 91% in wide potential range (−0.7 ∼ −0.3 V), which exceeds almost all metal contained carbon materials to our knowledge. As the first study of fungi residue towards H 2 O 2 electrogeneration, this novel approach provides a highly promising and low cost electrocatalyst for real production, moreover, exploring a new direction for H 2 O 2 electrocatalyst development. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
323. Recovery of methacrylic acid from dilute aqueous solutions by ionic liquids though hydrogen bonding interaction.
- Author
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Bai, Yinge, Yan, Ruiyi, Huo, Feng, Qian, Jianguo, Zhang, Xiangping, and Zhang, Suojiang
- Subjects
- *
METHACRYLIC acid , *IONIC liquids , *AQUEOUS solutions , *HYDROGEN bonding , *CARBOXYLIC acids , *CHEMICAL industry - Abstract
The recovery of carboxylic acids from dilute aqueous solution is necessary but difficult in chemical industry. Methacrylic acid (MAA) is an important chemical widely used in polymer industry. In this work, the recovery of carboxylic acid from diluted aqueous solution by liquid-liquid extraction using ionic liquids (ILs) as extractants was studied. MAA was employed as model carboxylic acid. The partition coefficients of MAA in biphasic system and the extraction efficiencies of MAA were determined for imidazolium-based ILs and quaternary ammonium salt ILs with different structure of cation and anion. The extraction conditions such as extraction time, extraction temperature, mass ratio of ILs to MAA aqueous solution, initial concentrations of MAA, and water content were evaluated. An internal mechanism of the MAA extract by ILs was revealed by combining solvatochromic study, FT-IR and quantum chemical calculations. The results show that the strong hydrogen bond basicity (β) of ILs results in the high partition coefficient of MAA, which provides guidance to molecular design of ILs for the high efficient extractive separation of MAA from diluted aqueous solution. Based on this, IL with strong hydrogen bond basicity ([N 8881 ]Cl) was used to extract MAA from dilute aqueous solution. Compared with hexane which is conventional solvent used in MAA extractive separation, [N 8881 ]Cl can get 49 times higher of partition coefficient value and the extraction efficiency reach 94.57% for the single-stage extraction. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
324. Synthesis of Acrylate Dual-Tone Resists and the Effect of Their Molecular Weight on Lithography Performance and Mechanism: An Investigation.
- Author
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Liu, Lifei, Li, Jintong, Song, Ting, Wu, Rong, Zhao, Weizhen, and Huo, Feng
- Subjects
- *
MOLECULAR weights , *LITHOGRAPHY , *FOURIER transform infrared spectroscopy , *ATOMIC force microscopy , *NUCLEAR magnetic resonance - Abstract
Acrylate photoresists have gained considerable attention in recent years owing to their high resolution, high sensitivity, and versality. In this work, a series of thermally stable copolymers are synthesized by introducing an isobornyl group, and well characterized using Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectra (1H-NMR). The effects of polymerization conditions on the molecular weight and their further influence on lithography are explored. By analyzing the thermal properties, film-forming capabilities, and the patterning behavior of these copolymers, a direct correlation between lithography performance and polymerization conditions is established via the molecular weight. In addition, the baking temperature of lithography is also optimized by atomic force microscopy (AFM), after which a line resolution of 0.1 μm is observed under the exposure of a 248 nm UV light and electron beam. Notably, our synthesized photoresist displays dual-tone resist characteristics when different developers are applied, and the reaction mechanism of acid-catalyzed hydrolysis is finally proposed by comparing the structural changes before and after exposure. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
325. Amorphous Co-Mo-B Film: A High-Active Electrocatalyst for Hydrogen Generation in Alkaline Seawater.
- Author
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Fang, Xiaodong, Wang, Xiangguo, Ouyang, Ling, Zhang, Longcheng, Sun, Shengjun, Liang, Yimei, Luo, Yongsong, Zheng, Dongdong, Kang, Tairan, Liu, Qian, Huo, Feng, and Sun, Xuping
- Subjects
- *
INTERSTITIAL hydrogen generation , *OXYGEN evolution reactions , *HYDROGEN evolution reactions , *SEAWATER , *FOAM , *HYDROGEN production , *ELECTROLYSIS - Abstract
The development of efficient electrochemical seawater splitting catalysts for large-scale hydrogen production is of great importance. In this work, we report an amorphous Co-Mo-B film on Ni foam (Co-Mo-B/NF) via a facile one-step electrodeposition process. Such amorphous Co-Mo-B/NF possesses superior activity with a small overpotential of 199 mV at 100 mA cm−2 for a hydrogen evolution reaction in alkaline seawater. Notably, Co-Mo-B/NF also maintains excellent stability for at least 24 h under alkaline seawater electrolysis. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
326. Mini-incision, Primary Chloleystorrhaphy in the Management of Cholecystolithiasis and Cholecystopolyps.
- Author
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Huo Feng, Luo Mingyi, and Ma Yuangui
- Published
- 1996
327. Hepatobiliary Cystadenoma A Case Report and Literature Review.
- Author
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Huo Feng, Luo Mingyi, Ma Qi, and Zhu Yong
- Published
- 1996
328. MODIFIED PERCUTANEOUS ENDOSCOPIC CHOLECYSTOPOLYPECTOMY.
- Author
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HUO FENG, LUO MING-YI, MA YUAN-GUI, ZHANG ZHI-CHENG, and QIU BAO-AN
- Published
- 1992
329. THE APPLICATION OF PERORAL CHOLANGIOSCOPY IN BILIARY DISEASES.
- Author
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Oiu Bao-an, Ma Yuan-gui, Huo Feng, and Jia Guang-yue
- Published
- 1993
330. A PRACTICAL AND COST-EFFECTIVE WAY TO BEGIN LAPAROSCOPIC SURGERY.
- Author
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LUO MING-YI, MA YUAN-GUI, HUO FENG, QIU BAO-AN, and ZHANG ZHI-CHENG
- Published
- 1992
331. "Three-dimensional environment-friendly" amino acid functionalized chitosan: Uranium adsorption performance and mechanism research.
- Author
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Zhu, Ruiqi, Zhang, Chunhong, Zhu, Lien, Liu, Lijia, Huo, Feng, Wang, Yudan, Bai, Jianwei, Ma, Fuqiu, and Dong, Hongxing
- Subjects
- *
ENDOTHERMIC reactions , *ENERGY development , *CLEAN energy , *ADSORPTION capacity , *ELECTROSTATIC interaction , *PHENYLALANINE - Abstract
To achieve the goals of "carbon peak and carbon neutrality" and sustainable development, we propose "Three-Dimensional Environment-Friendly" materials to balance the urgent need for the development of clean energy and the reduction of secondary environmental pollution during adsorbent preparation. In this study, three novel chitosan adsorbents (CMNSC-Leu , CMNSC-Pro , CMNSC-Phe) for uranium adsorption were designed on the basis of molecular level and successfully synthesized with three different amino acids (leucine, proline, phenylalanine) through amidation reaction in an aqueous environment using a sustainable green chitosan material. The uranium adsorption capacity of the three adsorbents was evaluated by batch adsorption, selectivity and recyclability studies. The adsorption reaction conformed to the pseudo-second-order model and was a spontaneous endothermic reaction. In particular, the maximum adsorption capacity of CMNSC-Pro for uranium was 462.7 mg·g−1 at C 0 = 100 ppm. In addition, CMNSC-Pro showed better selectivity and good reusability. DFT calculation and IRI diagram were applied in this work to analyze the unique structure and adsorption process of CMNSC-Pro from the perspective of structure. Uranium was adsorbed by CMNSC-Pro via coordination, electrostatic interaction, and intraparticle diffusion. This work provided a new idea for the structural design and construction of new high-efficiency biomass adsorbents. [Display omitted] • Green and sustainable biomass chitosan as raw material • Bis-substituted chitosan was achieved by amidation reaction in aqueous. • Adsorbents could adsorb up to 462.7 mg·g−1 for uranium at 100 ppm. • Coordination mechanism in CMNSC-Pro: UO 2 2+ coordinated by O C in CNO and COOH. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
332. A 3D conducting scaffold with lithiophilic carbon nanoparticles for stable lithium metal battery anodes.
- Author
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Li, Zhicun, Fan, Hailin, Zhang, Zheng, Wang, Liwei, Cao, Xiaoju, Gao, Wencao, Liu, Yuwen, Liu, Yanxia, and Huo, Feng
- Subjects
- *
CARBON paper , *DISCONTINUOUS precipitation , *METAL-organic frameworks , *LOW voltage systems , *ANODES - Abstract
Li metal anode with high capacity, negative potential and low density is regarded as the most promising anode material. Unfortunately, its commercialization is greatly limited by Li dendrites. Here, a 3D carbon paper scaffold with lithiophilic carbon nanoparticles is synthesized as a Li host via the carbonization of metal-organic framework and the doping of oxygen atom. Carbon nanoparticles effectively improve the specific surface area of carbon paper that can low the local current density and provide rich internal spaces for Li reservoir. In addition, the rich lithiophilic groups (such as ZnO, nitrogen atom and oxygen atom) can regulate a uniform Li+ flux and achieve a controllable Li deposition. Based on these structural advantages, uniform nucleation and growth of Li metal have been realized. Especially, the symmetric cell renders an outstanding cyclic stability for 750 h with an ultra-low polarization voltage of 14 mV at 1 mA/cm2. Additionally, the full cell partied with a LiFePO 4 cathode displays an initial specific capacity of 138.1 mAh/g, and even maintains 97.7 % capacity retention after 120 cycles at 0.5C. Therefore, this strategy presents a universal approach to construct porous hosts with abundant lithiophilic sites for long-lifespan Li metal batteries. [Display omitted] • We propose a strategy to construct porous hosts with abundant lithiophilic sites. • Zn–O@CP host can regulate uniform Li ionic flux and dendrite-free Li deposition. • Zn–O@CP host displays a low polarization voltage of 14 mV for 750 h. • Zn–O@CP host can be applied to both in anode-free cells and in Li metal cells. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
333. KLF4 Affects Acute Renal Allograft Injury via Binding to MicroRNA-155-5p Promoter to Regulate ERRFI1.
- Author
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Zhao, Jiquan, Zhao, Jiqiang, He, Zhaohui, Lin, Minzhuan, and Huo, Feng
- Subjects
- *
HOMOGRAFTS , *KRUPPEL-like factors , *KIDNEY injuries , *WOUNDS & injuries , *OXIDATIVE stress - Abstract
Kruppel-like factor 4 (KLF4) owns the promising potential in treating kidney injury, which inevitably occurs during renal allograft. Given that, this research targets to unveil KLF4-oriented mechanism from microRNA-155-5p/ERBB receptor feedback inhibitor 1 (miR-155-5p/ERRFI1) axis in acute renal allograft injury. Mice were injected with miR-155-5p-related sequences before acute renal allograft modeling. Afterwards, serum inflammation, along with oxidative stress, renal tubular injury, and apoptosis in renal tissues were detected. HK-2 cells were processed by hypoxia/reoxygenation (H/R) and transfected with miR-155-5p- or ERRFI1-related sequences, after which cell proliferation and apoptosis were measured. KLF4, miR-155-5p, and ERRFI1 expressions and their interaction were tested. KLF4 and miR-155-5p levels were enhanced, and ERRFI1 level was repressed in mice after acute renal allograft and in H/R-treated HK-2 cells. KLF4 bound to the promoter of miR-155-5p. Depleting miR-155-5p reduced serum inflammation and attenuated oxidative stress, renal tubular injury, and apoptosis in mice with acute renal allograft injury. Downregulating miR-155-5p facilitated proliferation and repressed apoptosis of H/R-treated HK-2 cells. miR-155-5p targeted ERRFI1. Knocking down ERRFI1 antagonized the effects of downregulated miR-155-5p on acute renal allograft injury, as well as on H/R-treated HK-2 cell proliferation and apoptosis. A summary displays that silencing KLF4 suppresses miR-155-5p to attenuate acute renal allograft injury by upregulating ERRFI1, which provides a way to control acute renal allograft injury. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
334. Influence of rate of voltage rise on positive leader inception in long-air-gap discharge.
- Author
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Li, Zhijun, Chen, Weijiang, Li, Chengrong, Bian, Kai, He, Huiwen, Huo, Feng, and Fan, Mian
- Subjects
- *
AIR gap (Engineering) , *PARTIAL discharges , *VOLTAGE , *DIELECTRIC breakdown - Abstract
Positive leader inception under different rates of voltage rise is a key element in physical modeling of dielectric breakdown of long air gaps and evolution of natural lightning. The leader inception phase comes first in long-air-gap discharge, including first corona, primary dark period, and second corona, which is also called "leader corona," portending leader inception. The Les Renardières Group has stated that the primary dark period is determined by the electrode curvature, based on which no leader inception model currently in use considers the influence of the rate of the applied voltage. To determine whether that assertion is true, an experimental scheme is designed so that impulse voltages can be applied with a large range of rise rates. With an increasing rate of voltage rise, the test results clearly show the following: (i) the curves relating the injected charge and inception voltage of the first corona present regular differences; (ii) the duration of the primary dark period decreases exponentially; (iii) the leader inception voltage and the difference between the leader and first-corona inception voltages present decreasing trends. These findings indicate that the formation of the dark period is related to more than just the electrode curvature, which is just one cause but may not be the essential reason for the dark period. The present findings suggest that the rate at which the applied voltage rises impacts the physical process of the streamer-to-leader transition during the dark period. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
335. Preparation and characterization of Ti/SnO2–Sb2O3–Nb2O5/PbO2 thin film as electrode material for the degradation of phenol
- Author
-
Yang, Xiupei, Zou, Ruyi, Huo, Feng, Cai, Duochang, and Xiao, Dan
- Subjects
- *
SURFACE chemistry , *TITANIUM dioxide films , *CHEMICAL decomposition , *ELECTROFORMING , *SURFACE analysis , *SCANNING electron microscopy , *X-ray diffractometers , *INDUSTRIAL wastes , *PHENOL removal (Sewage purification) - Abstract
In this work, a novel electrode of titanium substrate coated with mixed metal oxides of SnO2, Sb2O3, Nb2O5 and PbO2 was successfully prepared using thermal decomposition and electrodeposition. The surface morphology and the structure of the prepared thin film were characterized by scanning electronic microscopy (SEM) and X-ray diffraction (XRD), respectively. Experimental results showed that the structure of the prepared electrode might be described as a Ti/SnO2–Sb2O3–Nb2O5/PbO2 thin film and its surface was mainly comprised pyramidal-shape β-PbO2 crystals. The modified electrode had higher oxygen evolution potential than that of other PbO2 modified electrodes. Electrocatalytic oxidation of phenol in aqueous solution was studied to evaluate the potential applications of this electrode in environmental science. The phenol removal efficiency in an artificial wastewater containing 0.50g/L phenol could reach 78.6% at 20°C and pH 7.0 with an applied electricity density of 20mA/cm2 and treatment time of 120min. When 21.3g/L chloride was added to this wastewater, the removal efficiency could reach to 97.2%. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
336. Pitaya-inspired Li Metal-free Prelithiation of silicon monoxide into anode materials for Li-ion batteries.
- Author
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Gao, Zhe, Chai, Fengtao, Liu, Fan, Liu, Jingbo, Zhao, Chongchong, Dong, Jiayu, and Huo, Feng
- Subjects
- *
SUPERCAPACITOR electrodes , *ELECTRON energy loss spectroscopy , *LITHIUM-ion batteries , *MICROCRYSTALLINE polymers , *X-ray photoelectron spectroscopy , *ANODES , *LITHIUM silicates - Abstract
Silicon monoxide (SiO), which has been verified as a potential anode material, can improve the energy density of Li-ion batteries (LIBs). These LIBs are crucial for the advancement of electric vehicles. However, the commercial application of SiO is severely limited due to poor initial Coulombic efficiency (ICE). In this study, we present a novel concept to enhance the ICE of silicon oxide-based anodes by collaboratively leveraging two distinct reaction theories: disproportionation reaction and the reaction between acidic oxide and alkali. Based on this concept, we utilize a chemical disproportionation-driven Li metal-free prelithiation method, enabling the in-situ growth of microcrystalline silicon and lithium silicate within amorphous silicon oxide, which bears a striking resemblance to pitaya seeds. This reaction yields unique lithium silicate and nano/micro-structured silicon surrounded by SiO (Si–SiO–Li x SiO y multicomponents, PD-SiO). This can be demonstrated via transmission electron microscopy (TEM), Electron energy loss spectroscopy (EELS) or X-ray photoelectron spectroscopy (XPS). The reaction product, PD-SiO, exhibits remarkable properties, including high ICE (82.5 %), high charging capacity (1419 mAh g–1), and highly stable cycling performance (94.6 % capacity retention after 200 cycles at 0.5 A g–1). This study offers a new approach to enhance the initial Coulombic efficiency of silicon monoxide. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
337. Computational insights into carbon dots: Evolution of structural models and structure–activity relationships.
- Author
-
Zhao, Xiao, Wei, Jishi, Song, Tianbing, Wang, Zhengren, Yang, Dawei, Zhang, Xirong, Huo, Feng, Zhang, Yanqiang, and Xiong, Huan-Ming
- Subjects
- *
STRUCTURE-activity relationships , *STRUCTURAL models , *CARBON composites , *ATOMIC models , *FLUORESCENT probes - Abstract
[Display omitted] • Offering directional strategies for modeling methods of carbon dots and composites. • Summarizing the crucial points of various modeling methods. • Exhibiting different practical applications to elucidate the modeling processes. As researchers have gained a deeper insight into the properties of carbon dots (CDs), their applications gradually spanned from fluorescent probing and bio-imaging to energy storage, catalysis, and other numerous fields in recent years. At the same time, computational methods are also employed to deepen the understanding of CDs on the other sides. In this process, the establishment of the statical atomic model and structure–activity relationship is becoming especially valuable. This review summarizes the progress to date in the construction of structural models referring to CDs and evaluates their significance in establishing structure–activity relationships. Specifically, the modeling strategy of CDs and CDs composites, and the functions of related models in explaining CDs as fluorescent reagents, biological probes, catalytic materials, and energy storage devices will be evaluated, aiming at offering some different insights for the design of more rational and reliable CDs-based models for the exploration of more novel characteristics and phenomena related to CDs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
338. Bidirectional redox catalyst with rambutan-like structure for advanced lithium-sulfur battery.
- Author
-
Zhao, Chongchong, Yang, Yi, Liu, Yanxia, Sun, Zixu, Zhang, Tao, Gao, Zhe, Huo, Feng, and Zhang, Yatao
- Subjects
- *
CATALYST structure , *LITHIUM sulfur batteries , *CATALYTIC activity , *QUANTUM dots , *OXIDATION-reduction reaction , *METAL-organic frameworks , *ELECTRIC batteries - Abstract
[Display omitted] • The rambutan-like structure of Pd@SS-CNR provides large specific surface area and abundant pores. • The Pd quantum dots act as bidirectional redox catalyst to suppress shuttle effect. • Li-S batteries with Pd@SS-CNR electrodes exhibited excellent electrochemical performance. The lithium polysulfide (LiPSs) shuttle effect and sluggish conversion kinetics hinder the commercial viability of lithium-sulfur (Li-S) batteries. To improve the properties of Li-S batteries, it is imperative to establish efficient pathways for Li-ions transmission by constructing conductivity channels of high quality, and to expedite the conversion kinetics of LiPSs by employing catalysts of exceptional activity. In this study, we synthesized a spherical superstructure of metal–organic framework nanorods (SS-MOFNR) using a self-assembly strategy with zinc-metal–organic framework (Zn-MOF) nanoparticles, followed by carbonization to obtain the spherical superstructure of carbon nanorods (SS-CNR). Subsequently, palladium nanoparticles were synthesized through the reduction and uniformly dispersed onto SS-CNR. The hollow porous structure facilitates the efficient utilization of sulfur and ensures the rapid diffusion of Li-ions. Additionally, Pd nanoparticles exhibit significant catalytic activity, effectively adsorbing LiPSs and bidirectional catalytic conversion of sulfur species, thereby effectively suppressing the shuttle effect of LiPSs. Therefore S/Pd@SS-CNR electrode demonstrates commendable electrochemical efficacy, as evidenced by its initial specific capacity of 1627.7 mAh g−1 at 0.1C and maintaining a specific capacity of 766.2 mAh g−1 even after 600 cycles at 0.5C. Moreover, it exhibits favorable cycle stability at 2C, retaining a reversible capacity of 502.3 mAh g−1 after undergoing 1000 cycles. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
339. Evaluation of the ex vivo liver viability using a nuclear magnetic resonance relaxation time-based assay in a porcine machine perfusion model.
- Author
-
OuYang, Qing, Liang, Guohai, Tan, Xiaoyu, He, Xiran, Zhang, Lin, Kuang, Weijian, Chen, Jianxiong, Wang, Shaoping, Liang, Mingju, and Huo, Feng
- Subjects
- *
NUCLEAR magnetic resonance , *LIVER transplantation , *GADOLINIUM compounds , *HYPOTHERMIA , *ISCHEMIA diagnosis - Abstract
There is a dearth of effective parameters for selecting potentially transplantable liver grafts from expanded-criteria donors. In this study, we used a nuclear magnetic resonance (NMR) relaxation analyzer-based assay to assess the viability of ex vivo livers obtained via porcine donation after circulatory death (DCD). Ex situ normothermic machine perfusion (NMP) was utilized as a platform for viability test of porcine DCD donor livers. A liver-targeted contrast agent, gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA), was injected into the perfusate during NMP, and the dynamic biliary excretion of the Gd-EOB-DTPA was monitored by measuring the longitudinal relaxation time (T1). The longitudinal relaxation rate (R1) of the bile was served as a parameter. The delay of increase in biliary R1 during early stage of NMP indicated the impaired function of liver grafts in both warm and cold ischemia injury, which was correlated with the change of alanine aminotransferase. The preservative superiority in cold ischemia of dual hypothermic oxygenated machine perfusion could also be verified by assessing biliary R1 and other biochemical parameters. This study allows for the dynamic assessment of the viability of porcine DCD donor livers by combined usage of ex situ NMP and NMR relaxation time based assay, which lays a foundation for further clinical application. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
340. Molecular dynamics simulation study of the solid polymer electrolyte that PEO grafted POSS.
- Author
-
Zhu, Yongxia, Cao, Shaokui, and Huo, Feng
- Subjects
- *
SUPERIONIC conductors , *MOLECULAR dynamics , *POLYELECTROLYTES , *GLASS transition temperature , *MOLECULAR weights , *SURFACE grafting (Polymer chemistry) - Abstract
• A new hybrid compound (POSS) was introduced to a conventional PEO-based polymer electrolytes. • The microscopic interaction between Li+ and other atoms in the systems were explored. • The molecular dynamics simulation method was used to calculate the dynamic properties of Li+. • High ionic conductivity has been obtained in the PEO grafted POSS system. Solid polymer electrolytes still face many problems for the development of energy devices. A new hybrid compound (POSS) grafted with a low molecular weight PEO segment was introduced to inhibit polymer crystallization and improve the ion conductivity. The microscopic interaction sites between Li+ and other atoms were studied in the grafted systems. The glass transition temperature shows that the grafting of POSS can effectively inhibit the crystallization of the polymer and form more microscopic amorphous regions. Comparing with a blank system and blending system, the improved electrical conductivity of Li ions was obtained. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
341. Structure and interaction properties of MBIL [Bmim][FeCl4] and methanol: A combined FTIR and simulation study.
- Author
-
Zhang, Yaqin, Zhang, Tian, Huo, Feng, Wang, Yanlei, Li, Xuehui, and He, Hongyan
- Subjects
- *
METHANOL , *LEWIS acidity , *COMPLEX ions , *METHANOL as fuel , *DENSITY functional theory , *MOLE fraction , *ION pairs - Abstract
Ionic liquids (ILs) are a kind of novel solvents of which some are green with many possible applications, e.g., as efficient catalyst. Structures and properties of ILs are determined by coulomb and van der Waals interactions and also by hydrogen-bonding between cations and anions. Particularly, metal-based ionic liquids (MBILs) exhibit excellent catalytic properties in the lignin conversions due to their superiority in paramagnetism, Lewis acidity, and electrochemistry. Nevertheless, the structural properties of MBILs are scarcely understood. Therefore, the hydrogen-bonding interactions between [Bmim][FeCl 4 and methanol at different concentration were studied in this work by using excess infrared spectroscopy, density functional theory (DFT) and molecular dynamics (MD) simulations. The results showed that hydrogen-bonding interactions between cations and anions of [Bmim][FeCl 4 were gradually weakened with increasing the concentration of methanol. However, cations and anions tended to bind together because of the original stable hydrogen-bonding network when the mole fraction of methanol was <0.2. The MD simulations verified that [Bmim][FeCl 4 could be dissociated into individual ions when the molar ratio of methanol to [Bmim][FeCl 4 exceeded 2 for the reason that methanol simultaneously interacted with cations and anions of [Bmim][FeCl 4. Due to the electron-donating group (–CD 3), which made positive contributions to the stability of the O–D···Cl hydrogen bond, methanol had priority to interacting with [FeCl 4 − anions. It was found that [Bmim][FeCl 4 ion clusters, [Bmim][FeCl 4 -methanol complex, and the free ions were the primary aggregation forms in the mixed systems. We hope that the findings obtained from this work can give an in-depth understanding of the hydrogen-bonding interactions between MBILs and methanol, which can take advantage of MBILs as a functional medium. • The microscopic interactions in the binary systems of metal-based ionic liquids and methanol were elucidated. • The effect of solvent concentration on the structure of hydrogen bonds was performed by FTIR, DFT and MD simulations. • Energy decomposition and RDG analysis visualized the composition of Non-Covalent Interactions. • Ion pairs were hardly broken apart when the molar concentration of methanol was <0.2. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
342. Sensitive determination of bisphenols in environmental samples by magnetic porous carbon solid-phase extraction combined with capillary electrophoresis.
- Author
-
Yang, Xiupei, Zhang, Maosen, Yang, Jing, Huo, Feng, Li, Yingying, and Chen, Lianfang
- Subjects
- *
SOLID phase extraction , *CAPILLARY electrophoresis , *BISPHENOLS , *ENVIRONMENTAL sampling , *FIELD emission electron microscopy , *FOURIER transform infrared spectroscopy - Abstract
• A new magnetic porous carbon was prepared by combustion combined with solvothermal method. • MSPE-CE-DAD for the simultaneous determination of four bisphenols was established. • The method can achieve effective enrichment of bisphenol compounds in environmental water samples. • The method is simple, efficient, sensitive, and environmentally friendly. Bisphenol compounds exist widely in the environment and pose potential hazards to the environment and human health, which has aroused widespread concern. Therefore, there is an urgent need for an efficient and sensitive analytical method to enrich and determine trace bisphenols in environmental samples. In this work, magnetic porous carbon (MPC) was synthesized by one-step pyrolysis combined with a solvothermal method for magnetic solid-phase extraction of bisphenols. The structural properties of MPC were characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and saturation magnetization analysis. Its adsorption properties were evaluated by adsorption kinetics and adsorption isotherm studies. By optimizing the magnetic solid-phase extraction and capillary electrophoresis separation conditions, a capillary electrophoresis separation and detection method for four bisphenols was successfully constructed. The results showed that the detection limits of the proposed method for the four bisphenols were 0.71–1.65 ng/mL, the intra-day and inter-day precisions were 2.27–4.03% and 2.93–4.42%, respectively, and the recoveries were 87.68%-108.0%. In addition, the MPC could be easily recycled and utilized, and even if the magnetic solid-phase extraction was repeated 5 times, the extraction efficiency could still be kept above 75%. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
343. A traffic light-type sensitive visual detection of mercury by golden nanoclusters mixed with fluorescein.
- Author
-
Deng, Wenqing, Dai, Rui, Hu, Pingyue, Li, Qianqian, Xiong, Xiaoli, Huang, Ke, and Huo, Feng
- Subjects
- *
TRAFFIC signs & signals , *MERCURY analysis , *FLUORESCEIN , *COLORIMETRY , *SERUM albumin - Abstract
A novel colorimetric sensor based on red-emitting bovine serum albumin‑golden nanoclusters (BSA-AuNCs) and green-colored fluorescein that exhibited traffic light-type color change was developed for ratiometric and visual detection of mercury (Hg). In the presence of Hg 2+ , the red fluorescence from BSA-AuNCs was quenched while the green fluorescein was inert thus as a reference. And it presented traffic light-type (red, yellow and green) color in the low, middle and high concentration of Hg 2+ . A potential mechanism was investigated by Energy Dispersive Spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). The selective quenching mechanism may be due to the formation of gold amalgam bonds between BSA-AuNCs and Hg 2+ . A linear correlation was constructed for Hg 2+ in the concentration range of 10–500 μg L −1 . A limit of detection (LOD) of 7.4 μg L −1 and a relative standard deviation (RSD, n = 7) of 0.4% were obtained, which can be used to monitor the concentration of Hg 2+ . In visual detection, as low as 0.1 μg mL −1 of Hg 2+ can be easily discriminated from the blank with the naked eye. The proposed method was validated by analysis of certified environment and food samples with satisfactory results. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
344. Alkylation of isobutane/butene promoted by fluoride-containing ionic liquids.
- Author
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Zhang, Honghua, Liu, Ruixia, Yang, Zhiqiang, Huo, Feng, Zhang, Ruirui, Li, Zihang, Zhang, Suojiang, and Wang, Yanji
- Subjects
- *
ALKYLATION , *ISOBUTANE , *BUTENE , *IONIC liquids , *CATALYSIS , *SULFURIC acid - Abstract
In this work, the alkylation of isobutane and butene, catalyzed by sulfuric acid in the presence of the fluoride–containing ionic liquids [Bmim][PF 6 ] and [Bmim][SbF 6 ], was investigated. The use of the binary mixture catalysts brought to a higher C 8 selectivity and longer catalyst lifetime, compared with the results obtained when working with sulfuric acid only. This was attributed to the formation of new species when [Bmim][PF 6 ] or [Bmim][SbF 6 ] are added to sulfuric acid. The acidolysis of [Bmim][PF 6 ] and [Bmim][SbF 6 ] was accompanied by the release of hydrogen fluoride (HF) and the decomposition of anions to [PF 6−x−2y (HSO 4 ) x (SO 4 ) y ] − and [SbF 6−x−2y (HSO 4 ) x (SO 4 ) y ] − , respectively. The presence of these new species after acidolysis was measured and confirmed by ion chromatography, 1 H–Nuclear Magnetic Resonance (NMR), 19 F–NMR and 31 P–NMR. The production of HF and the complexation of anions and carbenium ions both play an important role in stabilizing the carbenium ion and improving the catalytic performance. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
345. High performance isolation of circulating tumor cells by acoustofluidic chip coupled with ultrasonic concentrated energy transducer.
- Author
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Qiu, Hui, Wang, Haoyu, Yang, Xiupei, and Huo, Feng
- Subjects
- *
ACOUSTIC radiation force , *ACOUSTIC field , *SOUND waves , *SYSTEMS on a chip , *ULTRASONICS , *TRANSDUCERS - Abstract
The isolation of circulating tumor cells (CTCs) from whole blood is a challenging task. Although various studies on the separation of CTCs by acoustofluidic devices have been reported, difficulties still persist, such as the complicated equipment, high cost, and difficult operation. Those problems should be resolved urgently. Herein, we developed an acoustofluidic chip separation system coupled with an ultrasonic concentrated energy transducer (UCET) system for efficient separation of CTCs. In the separation system, the acoustically sensitive particles were pre-focused by inertial forces of the PDMS chip channel structure. Then, the particles with different sizes were separated by acoustic radiation forces (ARF). In this study, the circulating tumor cells was simulated (CTCs-like particles) by aminated mesoporous acoustically sensitive particles (MSN@AM) encapsulated carboxylate polystyrene microspheres (PS-COOH). Subsequently, efficient CTCs-like particles separation was achieved by the acoustofluidic chip coupling system. This study effectively separated polystyrene microspheres carrying acoustically sensitive particles (MSN@AM@PS-COOH). However, the MSNs agglomerates and PS microspheres without acoustically sensitive particles did not show phenomenon of separation. This method allows to efficiently separate 2 µm MSNs agglomerates,8.0–8.9 µm PS microspheres and 10–10.5 µm MSN@AM@PS-COOH particles. It is demonstrated that the CTCs-like particles show more sensitive response, longer moving distance, and more obvious separation effect at the condition of the low frequency traveling wave sound field (20 kHz from UCET). This system can maintain the same separation with reduced amount of reagents used for cancer detection. It may provide a reliable basis for sorting out CTCs efficiently from the whole blood of cancer patients. [Display omitted] • CTCs-like particles were simulated by mesoporous acoustically sensitive particles. • CTCs-like particles show obvious separation effect at the low frequency traveling wave sound field (20kHZ from UCET). • We developed an acoustic fluidic chip separation system coupled with the UCET for efficient separation of CTCs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
346. Manipulating mechanism of the electrokinetic flow of ionic liquids confined in silica nanochannel.
- Author
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Qin, Jingyu, Wang, Yanlei, Gan, Zhongdong, Ma, Weili, Huo, Feng, Nie, Yi, Yang, Chao, and He, Hongyan
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- *
ION flow dynamics , *IONIC liquids , *MOLECULAR dynamics , *CHEMICAL processes , *FLUX flow , *SILICA fibers - Abstract
• MD simulations of electrokinetic nanoconfined ionic liquids flow were performed. • The perpendicular configuration of cation at the silica surface was identified. • Modulating mechanism of external stimuli on electrokinetic flow of ionic liquids. • Developed quantitative relation between streaming current and external stimuli. The electrokinetic flow of ionic liquids (ILs) is widely used in electrochemical engineering applications. Herein, flow behavior and controlling mechanism of ILs driven by electrical field were investigated via molecular dynamics simulations. During the flow process, the cations prefer to allocate at the interface in a perpendicular configuration, while the anions tend to distribute randomly. In the interface region, the perpendicular cations and accumulated ILs would significantly enhance the local viscosity of ILs, which dominates the velocity distribution and total flux of the electrokinetic flow of confined ILs. Compared with the pressure and surface charging density, the nanochannel size would induce a larger impact on the average velocity, total flux, and streaming current of the electrokinetic flow of confined ILs. These quantitative results on the electrokinetic flow are crucial for the rational design of ILs-based devices or other chemical engineering processes. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
347. Mechanistic insights into the luminescent sensing of nitrophenol compounds by a cationic Zn-based metal-organic framework.
- Author
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Liu, Yuhang, Wang, Yaohui, Zhang, Yi, Karmaker, Pran Gopal, Zhang, Lilei, Huo, Feng, Yang, Xiupei, and Zhao, Bin
- Subjects
- *
POLLUTANTS , *METAL-organic frameworks , *NITROAROMATIC compounds , *NITROPHENOLS , *ALIPHATIC compounds , *IMIDAZOLES , *NITRO compounds - Abstract
Nitroaromatic compounds (NACs) are considered as a kind of toxic chemicals that pose a serious danger to the survival of animals and humans. Therefore, it is of great significance to develop an efficient and rapid method for detecting nitroaromatic explosives. Up to now, fluorescence metal-organic framework (MOF) has been widely used to detect NACs in environmental pollutants because of their many active sites and bare functional groups. In this work, we have synthesized a cationic Zn-based MOF (called F1) based on bis-(imidazole) ligands with the formula of [Zn 3 (TIAB) 2 (IMDC) 2 ]·(NO 3) 2 ·(DMF) 2 ·(H 2 O) 2 (TIAB = [(1,2,4,5-tetra(1H-imidazole-1-yl)benzene)], IMDC = 4,5-imidazoledicarboxylic acid, DMF = N,N-Dimethylformamide). Crystal structure analysis reveals that F1 possesses a three-dimensional (3D) framework with (4,8)-coordinated network. TIAB linkers connect the Zn(II) atoms to construct a 2D network, the deprotonation of the hydroxyl groups on the two carboxyl groups of the IMDC ligand, and the protonated IMDC2− dangling fills the channel connected to two Zn1 atoms and one Zn2 atom, which are further connected TIAB ligands to form a 3D cationic framework. The results reveal that, compared with nitro aliphatic and aromatic compounds, the solvent-free F1 is highly sensitive and has excellent selectivity for nitroaromatic explosives, especially for 2,4,6-trinitrophenol (TNP). The quenching efficiency of TNP is as high as 91.67% (K sv = 56760 M−1, LOD = 0.78 μM). The solvent-free F1 can be reused at least five times, and the response time to TNP is less than 30 s. The sensing and detection mechanisms of the solvent-free F1 to various NACs have been studied in detail. Finally, the response of solvent-free F1 to a variety of NACs was analyzed by density functional theory. [Display omitted] • A cationic Zn-based MOF shows good selectivity and sensitivity to nitroaromatic compounds. • Distinguish between nitroaromatic and nitro aliphatic compounds. • F1 can quickly detect TNP within 30 s and cycle five times to maintain the stability of the structure. • Reveal a variety of detection mechanisms through experiments and theoretical calculations. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
348. Ionic liquids screening for lignin dissolution: COSMO-RS simulations and experimental characterization.
- Author
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Yu, Ke, Ding, Wei-Lu, Lu, Yumiao, Wang, Yanlei, Liu, Yanrong, Liu, Guangyong, Huo, Feng, and He, Hongyan
- Subjects
- *
LIGNIN structure , *LIGNANS , *LIGNINS , *IONIC liquids , *ACTIVITY coefficients , *HYDROGEN bonding - Abstract
• COSMO-RS is used for screening > 103 ILs with highly efficient in lignin dissolving. • Calculations and experiment prove the dissolving of IL is mainly modulated by H-bond. • [PMpyrr][OAC] ILs with the ability to dissolve lignin strongly. • The solubility of lignin in IL is related to the structure of lignin model. As the second most abundant terrestrial polymer, lignin has emerged as a major sustainable source for the production of fuels, chemicals, and materials. However, efficient screening of solvents for lignin dissolving faces great challenges. In this work, COSMO-RS was used to screen 3886 ionic liquids (ILs) composed of 58 cations and 67 anions, to find out the most effective ones for lignin dissolving by considering the critical items of logarithmic infinite dilution activity coefficient (lnγ∞) and σ-profiles. The substantial improvement of lignin dissolution was achieved in [PMpyrr][OAc] IL by both simulations and experiments validations. Moreover, it was found that the anions dominate the dissolution process and the strongly polar anions exhibit better dissolution ability. Furthermore, the underlying mechanism originated from the hydrogen bond (H-bond) between ILs and lignin was also revealed and systemically analyzed from donor and acceptor ability, indicating that high lignin solubility is reached in the ILs with stronger ability to form H-bond acceptors. This work leads to possible ways toward developing more selective and efficient lignin dissolution methods based on solvent properties. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
349. Development of a coarse-grained force field model of polymeric 1-vinyl-3-ethylimidazolium tetrafluoroborate ionic liquids.
- Author
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Li, Qifeng, Guo, Yandong, Tong, Jiahuan, He, Hongyan, Zhang, Xiaochun, and Huo, Feng
- Subjects
- *
TETRAFLUOROBORATES , *IONIC liquids , *MOLECULAR dynamics - Abstract
• A novel coarse-grained model for poly (ionic liquids) system was developed. • The potential parameters of coarse-grained model are obtained by Boltzmann and iterative Boltzmann inversion method. • The structural and thermodynamic properties could been reproduced under the CG model comparing with the AA force field. A novel coarse-grained (CG) model for poly (1-vinyl-3-ethylimidazolium) tetrafluoroborate ([PVEim][BF 4 ]) was developed with the all-atom (AA) molecular dynamics simulations as a benchmark. In this model, the bonded and non-bonded potential parameters of CG force field were obtained by Boltzmann and iterative Boltzmann inversion, respectively. The simulation results show that the novel CG model can accurately describe the structural characteristics and reproduce the thermodynamic properties comparing with the AA force field model. The deviation of densities values between CG model and experiment was within 5% at 298 K. This work can be a useful guide to the computational for large-scale PILs systems. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
350. Lightning Current Measurement Method Using Rogowski Coil Based on Integral Circuit with Low-Frequency Attenuation Feedback.
- Author
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Xiao Y, Jiao H, Huo F, and Shen Z
- Abstract
A lightning current measurement method using a Rogowski coil based on an integral circuit with low-frequency attenuation feedback was proposed to address the issue of low-frequency distortion in the measurement of lightning currents on transmission lines using Rogowski coils. Firstly, the causes of low-frequency distortion in lightning current measurements using Rogowski coils were analyzed from the perspective of frequency domains. On this basis, an integration correction optimization circuit with a low-frequency attenuation feedback network was designed to correct the low-frequency distortion. The optimized integration circuit can also reduce the impact of low-frequency noise and the DC bias of the operational amplifier (op-amp) on the integration circuit due to the high low-frequency gain. Additionally, a high-pass filtering and voltage-divided sampling circuit has been added to ensure the normal operation of the integrator and improve the measurement range of the measurement system. Then, according to the relationship between the amplitude-frequency characteristics of the measurement system and the parameters of each component, the appropriate types of components and op-amp were selected to expand the measurement bandwidth. Finally, a simulation verification was conducted, and the simulation results show that this measurement method can effectively expand the lower measurement frequency limit to 20 Hz, correct the low-frequency distortion caused by Rogowski coils measuring lightning currents on transmission lines, and accurately restore the measured lightning current waveform.
- Published
- 2024
- Full Text
- View/download PDF
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