JOURNAL OF CATALYSIS
·
2013
·
IF 5.787
Lin Guo,Yu Fan,Xiaojun Bao,Gang Shi,Haiyan Liu
Silicoaluminophosphate (SAPO-11) samples with enhanced acidity were synthesized by two-stage crystallization in the presence of dodecyltrimethylammonium bromide (DoTAB), in which the Si source was added after the aluminophosphate framework was formed. The structure, elemental composition, acidity, Si environment, and n-octane di-branched isomerization of the as-synthesized SAPO-11 with small crystallites were investigated. The results showed that compared with the conventional one-stage crystallization, the two-stage crystallization produced more Si borders in the resulting SAPO-11. Among the SAPO-11 samples synthesized by two-stage crystallization, the SAPO-11 with the optimal DoTAB content (mol(DoTAB)/mol(SiO 2 ) = 0.015) had the most Si( n Al) (0 < n < 4) species with moderate and strong Brønsted acidity. The catalyst based on the small crystallite SAPO-11 containing a greater number of moderate and strong Brønsted acid sites exhibited superior performance for n-octane di-branched isomerization. This two-stage DoTAB-assisted crystallization opens a new route to enhancing the SAPO-11 acidity and can be extended to the other SAPO molecular sieves.
研究领域:
化学工程
·
催化科学
·
材料科学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Mengshuai Liu,Bo Liu,Shifa Zhong,Lei Shi,Lin Liang,Jianmin Sun
In this contribution, a series of N-heterocyclic compounds cooperated with ZnBr2 catalyst for chemical fixation of CO2 to cyclic carbonates was developed without utilization of additional organic solvents. It was found that the catalytic activity of N-heterocyclic compounds could be obviously enhanced in the presence of ZnBr2, and the N-methylimidazole (Mim)/ZnBr2 catalytic system was the most efficient among the catalysts employed. Under the optimum reaction conditions, 99% yield of propylene carbonate was achieved with TOF of 474 h–1, and the catalysts were also versatile for CO2 cycloaddition with less active epoxides such as styrene oxide and cyclohexene oxide. Furthermore, a possible synergistic catalytic mechanism was proposed. Moreover, the rate constants were determined as a function of reaction temperature in the range of 130–160 °C, the activation energy was determined to be 41.1 kJ·mol–1, and the kinetic equation on the synthesis of propylene carbonate catalyzed by Mim/ZnBr2 was also obtained.
研究领域:
化学工程
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Hui Xue,Ziqing Zhao,Rui Chen,John L. Brash,Hong Chen
Hypothesis : Poly( N -isopropylacrylamide) microgels are used extensively in the design of drug carriers, surfaces for control of cell adhesion, and optical devices . Particle size is a key factor and has a significant influence in many areas. Experiments : In this work, precise control of the particle size of poly( N -isopropylacrylamide) microgels was achieved by controlling the separation distance of the poly( N -isopropylacrylamide) chains. Dibromoalkanes of different size were used as an adjustable “molecular ruler” to measure molecular dimensions in poly( N -isopropylacrylamide) nanoaggregates at the critical crosslinking temperature. Findings : We find that the chain separation distance decreases as the temperature increases with a sharp decrease over the 55-to-65 °C interval. Based on the observed relationships between chain separation and crosslinker, the particle size of poly( N -isopropylacrylamide) microgels can be regulated by changing the length of the “molecular ruler” (crosslinker) at the same temperature. Furthermore, for partly crosslinked poly( N -isopropylacrylamide) microgels that contain free crosslinkable sites, the particle size can be reduced still more by further crosslinking (“re-crosslinking”) with crosslinkers of different size. It is shown that the particle size can be regulated by adjusting the length of “molecular ruler” and the degree of crosslinking. This work provides a “molecular level” method for precise control of poly( N -isopropylacrylamide) microgel particle size.
研究领域:
材料科学
·
生物医学工程
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 73
·59286-59291
·
IF 3.84
Shifeng Li,Min Xing,Haiyan Wang,Li Zhang,Yiman Zhong,Lei Chen
In this work, water-soluble ZnS quantum dots (QDs) modified with 3-mercaptopropionic acid (MPA), L-cysteine (L-Cys) and thioglycolic acid (TGA) were synthesized. The nanostructure and optical properties were characterized by X-ray powder diffraction (XRD), Transmission electron microscopy (TEM), UV-Vis absorption spectrum and fluorescence spectrum. Through the study of the ZnS QDs effects on the chemiluminescence (CL) system of luminol, we found that ZnS QDs could obviously enhance the CL of the luminol–N-bromosuccinimide (NBS) system in an alkaline medium. At the optimal experimental conditions, we researched the impact of 17 kinds of amino acids on this system. It was found that L-tryptophan (Trp) and L-tyrosine (Tyr) had significantly inhibitory effects on luminol–NBS–ZnS QDs CL. Based on the inhibitory effects, a novel CL method with a wider linear range and lower detection limit for determination of Trp and Tyr was developed. The detection limits were 1.5 × 10−11 g mL−1 and 2.0 × 10−10 g mL−1, respectively. The possible CL reaction mechanism was also discussed briefly.
研究领域:
分析化学
·
生物化学
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Mingliang Dong,Weijin Qian,Xingzhen Liu,Yawei Chen,Weijun Huang,Changkun Dong
N-doped Carbon nanotube (NCNT)-Pd nanocomposites were fabricated by two convenient methods to make thermo-cell (TEC) electrodes. NCNTs were first synthesized on the alloy substrate (AS) using electrophoretic deposition technique, then Pd nanoparticles were coated on the surface of NCNT by magnetron sputtering. The TEC electrodes were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. The TEC performances of the NCNT-Pd nanocomposite electrode were enhanced significantly compared to those of the NCNT electrode with the current density of 58.4 A·m −2 and the power density of 1.08 W·m −2 , due to better catalytic activity and more activation sites. Meanwhile, the relative conversion efficiency of 1.04% was reached. This investigation suggests that the construction of the NCNT-Pd nanocomposite electrode could effectively improve the TEC performances of NCNT electrodes, very promising for the heat energy harvesting applications.
研究领域:
材料科学
·
能源技术
·
纳米技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
He-Qiang Chang,Guo-Hua Zhang,Kuo-Chih Chou
Electrochemical water splitting is considered a sustainable route for the hydrogen industry. In this work, Mo 2 C/MoC heterostructure supported on N -doped carbon (Mo 2 C/MoC@NC) was prepared via a carbonization strategy. For the product (Mo 2 C/MoC@NC-1-2) fabricated with a g-C 3 N 4 / ammonium molybdate tetrahydrate molar ratio of 1:2 at 700 °C under 10%CH 4 /H 2 atmosphere, a high stability and good HER activity with a η 10 of 113 mV in 1M KOH were achieved. To further enhance the catalytic performance of the synthesized Mo 2 C/MoC@NC, the phosphating strategy was proposed for the preparation of Mo 2 C/MoC/MoP heterostructure supported on N-doped carbon (Mo 2 C/MoC/MoP@NC). When the precursor Mo 2 C/MoC@NC-1-2 was phosphated at 650 °C with a heating rate of 5 °C min −1 and kept for 0 min, the as-synthesized Mo 2 C/MoC/MoP@NC-650-0 exhibits good HER catalytic activity with a pretty low η 10 of 78 mV, a j 0 of 0.398 mA cm −2 , and a Tafel slope of 52 mV dec −1 in 1M KOH. This good activity of HER can be ascribed to the N-doped carbon as substrate and the construction of transition metal-based heterostructures.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Di Pang,Yue Liu,Haiou Song,Duozhe Chen,Weiqing Zhu,Rumeng Liu,Hu Yang,Aimin Li,Shupeng Zhang
A trace Ti 3+ - and N-codoped TiO 2 nanotube array (TiON) anode is fabricated by electrochemical reduction after introducing nitrogen into the TiON. The TiON anode material is characterized by scanning electron microscopy, X-ray diffraction, Raman spectra and X-ray photoelectron spectroscopy. Electrochemical analyses of TiON, including cyclic voltammetry, electrochemical impedance spectroscopy and linear scan voltammetry, are conducted to confirm that the electrochemical performance could be significantly improved by electrochemical reduction and N doping. The achieved TiON anode is applied to the electrocatalytic oxidation of tetracycline (TC) and metronidazole (MNZ). The effect of applied current density, initial solution pH and initial TC/MNZ concentration on the reaction kinetics is systematically evaluated to obtain the optimal conditions. The degradation processes follow an apparent first-order kinetic model in all conditions. After 240 min of reaction time, the TC removal efficiency, chemical oxygen demand (COD) removal rate and total organic carbon (TOC) removal rate are >99%, 92.86% and 74.98%, respectively. The MNZ removal efficiency, COD and TOC removal rate achieved are >99%, 93.03% and 79.30%, respectively, after 240 min of degradation. The excellent removal efficiency of TC and MNZ indicates that this TiON anode is a promising material in the practical application of removing antibiotics from water.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Changwei Li,Zhefeng Gu,Songming Zhu,Dezhao Liu
This study evaluated the contribution of biotic and abiotic routes to the 17 β -estradiol (E2) removal in moving bed biofilm reactors (MBBRs), and uncovered the interrelation between the E2 removal routes and biofilm characteristics, which was not researched in previous literature. Three MBBRs with different C/N ratios (0 for C/N 0 ; 2 for C/N 2 ; and 5 for C/N 5 ) were operated in continuous mode. A 65-day degradation demonstrated that the MBBRs had high potential to remove E2 regardless of the C/N (E2 removal greater than 99% for all MBBRs; P > 0.05). Further batch tests showed that the E2 removal mainly resulted from heterotrophic activities for all MBBRs, accounting for approximately 85% for all MBBRs (P > 0.05), followed by nitrification (10–11%) and adsorption (4–5%). Importantly, lower adhesive force likely led to higher E2 adsorption onto biofilms. Besides, enhanced ammonia oxidizing rate (AOR) was consistent with the high contribution of nitrification to the E2 attenuation. Importantly, heterotrophic activity was positively correlated with its contribution to E2 removal (r = 0.99, P < 0.05). To sum, the results obtained in this study helped to understand the E2 removal routes in nitrifying biofilm systems.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Xu Tian,Lijia Yao,Xiuxiu Cui,Rongjun Zhao,Xuechun Xiao,Yude Wang
Fast and effective detection of harmful gases is crucial criterion for the current development of gas sensors. In this paper, a novel n-butanol gas sensor using Al-doped CdIn 2 O 4 nanofibers (ACO NFs) is synthesized by an electrospinning method . The different morphologies of the as-prepared ACO NFs are controlled by doping different Al contents . Systematic characterizations demonstrate that the doping of Al to CdIn 2 O 4 NFs would enhance the reaction activities between the gas and sensing materials, such as generating large amounts of adsorbed oxygen and improving the specific surface area of sensing materials. The results show that the detection limit of all prepared sensors for n-butanol is sub-ppm, and less than 250 ppb. The optimal Al-doped CdIn 2 O 4 (5.0% Al/Cd molar ratio) based gas sensor results in 3.32-fold enhancement in gas response to 200 ppm n-butanol at an operating temperature of 300 °C and exhibits excellent long-term stability compared with the pure CdIn 2 O 4 . Hence, ACO NFs can be regarded as a promising sensing material for low-concentration n-butanol gas detecting. Also, the mechanisms for improving the sensing performance of ACO NFs based gas sensor are proposed.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Xianyi Tang,Cheng Tong,Lianqiao Tan,Zidong Wei,Meng Wang
Lithium-Sulfur Batteries (LiSBs) are prevented to apply in practice by the irreversible loss from the cathode and difficult conversation kinetics of lithium polysulfides (LiPSs). An ideal S host material should possess high conductivity and sufficiently dispersed catalytic active sites to precisely restore the dissolved LiPSs to the surface of the S host material. In traditional catalyst design, porous carbonaceous materials are often selected as carriers for the nano-catalytic activity sites. However, non-polar pure carbon interfaces, where without nano-catalytic activity sites covered, have a very weak affinity to LiPSs. Here, we use ammonia as a nitrogen source to anneal the reduced aerogel (graphene oxide (rGO) supported nano-TiO 2 ) at high temperatures. The N element is atomically doped into the lattice of the carbon matrix, and the nano-TiO 2 is converted to nano-TiN. A hierarchically porous and high conductivity TiN/N-C is prepared, in which the nano-TiN is well dispersed on the surface of N-doped rGO as an active center for catalyzing LiPSs conversion. The doped-N elements significantly increase the proportion of the polar surface. The S@TiN/N-C composite cathode delivered an excellent long-life cycling performance, and the reversible discharge specific capacity faded from 1224 ± 16 to 675 ± 31 mAh g −1 after 930 cycles. More importantly, after 150 cycles with a high S loading, a reversible areal capacity of 4.1 mAh cm −2 can be achieved.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2025
·
IF 3.3
Zhao Bingshan,Micklefield Jason,Wang Yonghua,Wang Fanghua
N-trans -feruloyltyramine (FLA) is one kind of phenylpropanoid compound found in various plants. Numerous studies have confirmed that it exhibits a wide range of physiological functions, such as antioxidant, ɑ-glucosidase inhibition, and anti-inflammatory activity. However, the low content of FLA in plants greatly limits its potential use in food and pharmaceutical industries. It is, therefore, very important to establish an effective synthesis of FLA. In this study, a green and efficient method to synthesize FLA was sought using an amide bond synthetase (ABS) biocatalyst. Ten kinds of ABS enzymes, including AlCfaL from Azospirillum lipoferum , were screened as the potential biocatalysts for the production of FLA. To obtain optimum reaction conditions, the effects of various parameters on conversion of FLA were firstly evaluated. Under the optimum conditions using 1 mM N-trans -ferulic acid, 50 mM tyramine (substrate ratio of 1:50), 10 mM MgCl₂, 8 mM ATP, and 35 µM AlCfaL enzyme at 30 °C with a shaking speed of 500 r/min for 48 h, maximum conversion rate of 74% was reached. Given that the amidation reaction is mediated by relative expensive ATP, we further optimized reaction systems to incorporate an ATP recycling system consisting of a polyphosphate kinase enzyme (CHU) and an inexpensive polyphosphate (PolyP) as the phosphate donor. Response surface methodology (RSM) based on five-level, five-variable central composite design (CCD) was used to evaluate the optimal parameters for the production of FLA. The effects of AMP, PolyP, AlCfaL, CHU concentrations, and reaction time on the conversion rate of FLA were analyzed. The optimum conditions derived via RSM were 7.12 mM AMP, 5.96 mg/mL PolyP, 39.72 μM AlCfaL, 27.68 μM CHU, and a reaction time of 36 h. Validation experiments conducted under these optimized conditions yielded an actual conversion rate of 63.5%, which compared well to the maximum predicted value of 64.2%.
研究领域:
生物化学
·
酶工程
·
食品科学
·
药学
✓ 已验证
DOI
PubMed
高影响因子
PHYSIOLOGICAL RESEARCH
·
2025
·
IF 2
D Shao,L Bai,Q Chen,Y Chen,Z Qiu,Y Liu,S Jin,Y Wu,J Dai
Trimethylamine N-oxide (TMAO) is involved in the development of kidney disease. However, the specific mechanism by which it leads to kidney injury is unclear. This study explored the role of regulated cell death in TMAO-induced kidney injury. We constructed a TMAO-induced chronic kidney injury model by intraperitoneal injection of TMAO (100 micromol/kg/day for three months). Plasma creatinine (Cre) and urea nitrogen (BUN) levels were measured to evaluate kidney function. Masson staining was used to evaluate kidney pathological changes. The expression levels of regulated cell death-related proteins were measured using western blotting. Plasma Cre and BUN, the area of kidney fibrosis in the TMAO group significantly increased. The western blotting results showed cleaved-Caspase-8, Caspase-8, Caspase-1, NOD-like receptor protein 3 (NLRP3), interleukin-1beta (IL-1beta), cleaved-gasdermin D (cleaved-GSDMD), Z-DNA binding protein 1 (ZBP1), phosphorylation of receptor-interacting protein kinase 3 (RIP3) and mixed-lineage kinase domain-like pseudokinase (MLKL) significantly elevated in the TMAO group. The transferrin receptor 1 (TFR1), ferritin heavy chain (FTH), ferroportin (FPN), nuclear factor erythroid 2-related factor 2 (NRF2), and glutathione peroxidase 4 (GPX4) protein expression in kidney tissue of the TMAO group significantly up-regulated. However, there was no change in iron and MDA levels. The results suggested that PANoptosis, including pyroptosis, apoptosis, and necroptosis components, might be involved in TMAO-induced chronic kidney injury.
研究领域:
肾脏病学
·
细胞生物学
·
分子生物学
·
病理学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）