SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Xiaoyun Lin,Zhenmao Zhu,Chengfei Zhao,Shaoguang Li,Qicai Liu,Ailin Liu,Liqing Lin,Xinhua Lin
In this study, we developed a simple, sensitive and label-free colorimetric sensor for trypsin and its inhibitor using oxidase mimicking activity of protamine-stabilized platinum nanoparticles units (Pro-PtNPs units). Protamine is designed to stabilize PtNPs and served as the substrate of trypsin hydrolysis. The results show that protamine combines several PtNPs together to form active units, which have stronger oxidase mimicking activity than other PtNPs. In addition, the Michaelis constant of the Pro-PtNPs units is smaller than negatively charged citrate capped PtNPs, suggesting that the positively charged Pro-PtNPs units have better affinity with 3,3′,5,5′-tetramethylbenzidine (TMB), which is inconsistent with previous reports. The protamine stabilizer could be hydrolyzed in the presence of trypsin, and the Pro-PtNPs units would be decomposed and aggregated, resulting in a decrease of catalytic activity of Pro-PtNPs units. The color of the solution would be reduced according to the decrease of catalytic activity, so the catalytic activity is linearly related to UV absorbance. The linear range of trypsin detected by this new method is 0.06 μg/mL˜0.6 μg/mL, and the detection limit down to 0.03 μg/mL. Pro-PtNPs units have been successfully applied to the determination of serum trypsin and screening of inhibitors.
研究领域:
生物化学
·
纳米医学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Hongyuan Xi,Song Zhou,Jinxi Zhou
NO is the main precursor of photochemical smog. Since the SCR system of marine diesel engines has many disadvantages, this paper proposes an effective wet method to remove NO from the exhaust gases of marine diesel engines. Experiments were performed in a bubble column reactor to study the absorption of NO using sodium persulfate (Na 2 S 2 O 8 )/urea ((NH 2 ) 2 CO) solutions from a simulated gas stream. The effects of various operating parameters on NO removal were investigated, including reaction temperature, urea concentration, Na 2 S 2 O 8 concentration and the initial pH value of Na 2 S 2 O 8 /urea solutions. The experimental results showed that the NO removal efficiency increased with increasing reaction temperature (25–80 °C) and increasing Na 2 S 2 O 8 concentration (0.01–0.2 mol/L). When the concentration of urea was higher than 0.5 mol/L at 60 °C, 1 mol/L at 70 °C or 2 mol/L at 80 °C, the NO removal efficiency increased with the increase of urea concentration (0.1–4 mol/L). The highest NO removal efficiency was 99.7%, occurring at 80 °C when the concentrations of Na 2 S 2 O 8 and urea were 0.1 mol/L and 4 mol/L, respectively, and the concentration of nitrate was 14.93 mg/L. The optimal urea conditions were well below the legal limit of 60 mg/L. The NO removal efficiency increased with the increase of initial pH value within the herein investigated range of 7–9. All the experimental data showed that the novel system not only achieved effective NO removal efficiency, but also reduced the nitrate in wastewater, which could thus be applied to denitrification of marine engine exhaust gases.
研究领域:
环境工程
·
大气污染控制
·
化学工程
·
海洋工程
·
能源与动力工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·Vol. 42
·期 1
·1660-1665
·
IF 2.605
Yanxia Zheng,Gang Dong,Liyong He,Gang Wu,Huade Zheng,Chunlin Deng
Calcium phosphate layers, which are widely applied on the surface of biomaterials, are important for improving tissue regeneration performance. The composition of layers formed on the surface of biomaterials differs depending on the soaking fluid. Herein, revised simulated blood fluid and fast calcification solution were investigated as immersing solutions for the mineralization of hydroxyapatite ceramics. The morphology of the hydroxyapatite particles and precipitate formation on the hydroxyapatite ceramics surface were characterized by transmission electron microscopy . Furthermore, scanning electron microscopy was used to examine the morphology of the bioactive ceramics surface. The structure of the layers was determined by selected-area electron diffraction. The prepared hydroxyapatite powders were characterized by powder X-ray diffraction. The results showed that hydroxyapatite was preferentially formed on the hydroxyapatite ceramics surface in revised simulated blood fluid and octacalcium phosphate precipitated in fast calcification solution. Additionally, the content of HCO 3 - in the mineralization fluid strongly influenced the crystal phase composition and morphology of the calcium phosphate layers on the bio-ceramics materials studied herein.
研究领域:
生物材料学
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组织工程
·
无机化学
·
生物医学工程
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牙科材料
·
骨再生
✓ 已验证
DOI
高影响因子
Defence Technology
·
2021
·Vol. 18
·期 10
·1852-1862
·
IF 3.172
Fa-yang Guan,Hui Ren,Wan-jun Zhao,Xin-zhou Wu,Qing-jie Jiao
To improve the thermal properties of aluminum (Al) in the energetic system, a coated structure with ammonium perchlorate (AP) was prepared by a facile approach. And N, N-Dimethylformamide (DMF) was chosen as an ideal solvent based on heterogeneous nucleation theory and molecular dynamics simulation. This coated structure could enlarge the contact area and improve the reaction environment to enhance the thermal properties. The addition of AP could accelerate oxidation temperature of Al with around 17.5 °C. And the heat release of 85@15 composition rises to 26.13 kJ/g and the reaction degree is 97.6% with higher peak pressure (254.6 kPa) and rise rate (1.397 MPa/s). An ideal ratio with 15 wt% AP was probed primarily. The high energy laser-induced shockwave experiment was utilized to simulate the reaction behavior in hot field. And the larger activated mixture of coated powder could release more energy to promote the growth of shockwave with higher speed up to 518.7 ± 55.9 m/s. In conclusion, 85@15 composition is expected to be applied in energetic system as a novel metal fuel.
研究领域:
材料科学
·
能源化学
·
热力学
·
纳米材料
·
燃烧学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 141
·期 18
·e55316
·
IF 2.7
Jifa Bian,Zhongbin Ye,Xuecheng Zheng,Chengwen Deng,Lei Tang
This work used aqueous solution free radical polymerization to create polymers of 2-acrylamide-2-methylpropane sulfonic acid, itaconic acid, and allyl polyoxyethylene ether as a high-temperature resistant retarder (APMS/IA/APEG, from now on referred to as AIA). Gel permeation chromatography, fourier transform infrared (FTIR), proton nuclear magnetic resonance ( 1 HNMR), and thermo-gravimetric analysis (TG) were used to characterize their molecular structure and characteristics. Tests were conducted on the thickening time, rheological characteristics, and compressive strength of AIA in cement slurries. The cement slurry thickened for 276 min at 180°C during the test, and the cement stone's 24-h compressive strength was consistently more than 20 MPa. The hydration products were analyzed using x-ray diffractometer and scanning electron microscopy methods, which were then coupled with molecular dynamics simulations to elucidate the AIA retarding mechanism. When AIA is added to a cement slurry, it forms a chelate structure with Ca 2+ and a strong adsorption layer on the surfaces of the cement particles. This stops the cement from hydrating. The AIA side chain, APEG, can wrap the active group in AIA at low temperatures. AIA exposes more adsorption groups because of the APEG chains stretching at higher temperatures. AIA can, therefore, be used for deep well operations at high temperatures.
研究领域:
材料科学
·
石油工程
·
高分子化学
·
水泥化学
·
胶体与界面科学
✓ 已验证
DOI
高影响因子
FLAVOUR AND FRAGRANCE JOURNAL
·
2012
·Vol. 27
·期 5
·378-385
·
IF 1.424
Zhangfu Zeng,Yanxiong Fang,Hongbing Ji
The reason for low encapsulation efficiency of vanillin compared to p -hydroxybenzaldehyde within β -cyclodextrin was investigated. Fourier transform infrared spectra proved intermolecular interaction between guest and β -cyclodextrin. UV–visible studies indicated that vanillin and p -hydroxybenzaldehyde form 1:1 inclusion complexes with β -cyclodextrin. Nuclear magnetic resonance and quantum computational methods gave the most favourable orientation in which the guest molecule (vanillin or p -hydroxybenzaldehyde) is totally sequestered in the hydrophobic cavity of the cyclodextrin with the phenolic end located near the primary hydroxyls of the β -cyclodextrin and the aldehyde group near the secondary hydroxyls with hydrogen bonding formation. Encapsulation efficiency of the β -cyclodextrin inclusion with vanillin is about 29% lower than that with p -hydroxybenzaldehyde. This result could be attributable to the effect that the side chain methoxy group weakened the guest/host non-covalent intermolecular interaction, specifically, hydrogen bond interaction. Copyright © 2012 John Wiley & Sons, Ltd.
研究领域:
药物化学
·
超分子化学
·
分析化学
·
药剂学
·
分子识别
·
计算化学
✓ 已验证
DOI
高影响因子
POLYMER
·
2018
·
IF 3.483
Jianting Zhang,Yanhong Cui,Xiaoqing Li,Hanqiang Yao,Deming Zhao,Ningren Jin,Jianrong Gao
A novel poly(hydroxy-p-phenylenebenzobisoxazole) (HPBO) with superior comprehensive properties was synthesized via self-polymerization of composite salt monomer (HD). The molecular simulation results of relative total energies and the activation energies indicated that the meta-carboxyl group was the active site of condensation reaction which was carried out by amidation . Further molecular simulation results showed that the most probable configuration of HPBO was ordered P1 conformation, and the conjugation and stability of HPBO were enhanced by increasing the number of repeat units. The introduction of mono-hydroxyl group contributes to the formation of intramolecular hydrogen bonds of HPBO molecules, which made HPBO exhibit the molecular structure of the two-dimensional conjugate & coplanar and improved the thermal stability relative to PBO and DHPBO. The simulation results were verified by corresponding experimental investigation.
研究领域:
高分子化学
·
材料科学
·
计算化学
·
物理化学
·
功能材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Bo Wang,Jinyu Wang,Yuan Chen,Zhiyong Xu,Wenbo Zhao
N-Benzyl-N-methyl-1-(methyl diphenyl silyl) methanamine (MPSA) with high thermal stability was synthesized for the absorption of SO 2 in the present work. The absorption capacity was measured at low partial pressures ranging from 0.002 to 0.016 bar and thermodynamic parameters, including enthalpy change (Δ H ) and entropy change (Δ S ) were calculated to analyze the absorption behavior. The desulphurization rates and absorption capacities at different temperatures and partial pressures were simulated based on thermodynamic parameters. An optimal absorption temperature T 1 that maximizes the absorption capacity, and an optimal desorption temperature T 2 that minimizes the desorption residual capacity and thermal desorption energy consumption were defined, and a function was proposed to calculate them. The kinetic behavior of the absorption was described using a pseudo-first-order model, and kinetic data at different temperatures and partial pressures were simulated based on a combination of kinetic and thermodynamic parameters. Ultimately, selectivity and cycles experiment showing MPSA has excellent CO 2 selectivity and thermal regeneration performance.
研究领域:
环境化学
·
气体分离
·
热力学
·
化学工程
·
功能材料
·
大气污染控制
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 28
·45046
·
IF 1.86
Fenglei Liu,Shuixia Chen,Yanting Gao,Yufang Xie
A solid amine adsorbent was prepared by modifying a porous polystyrene resin (XAD-4) with chloroacetyl chloride through a Friedel–Crafts acylation reaction, followed by aminating with tetraethylenepentamine (TEPA). The adsorption behavior of CO 2 from a simulated flue gas on the solid amine adsorbent was evaluated. Factors that could determine the CO 2 adsorption performance of the adsorbents such as amine species, adsorption temperature, and moisture were investigated. The experimental results showed that the solid amine adsorbent modified with TEPA (XAD-4-TEPA), which had a longer chain, showed an amine efficiency superior to the other two amine species with shorter chains. The CO 2 adsorption capacity decreased obviously as the temperature increased because the reaction between CO 2 and amine groups was an exothermic reaction, and its adsorption amount reached 1.7 mmol/g at 10 °C in dry conditions. The existence of water could significantly increase the CO 2 adsorption amount of the adsorbent by promoting the chemical adsorption of CO 2 on XAD-4-TEPA. The adsorbent kept almost the same adsorption amount after 10 cycles of adsorption–desorption. All of these results indicated that amine-functionalized XAD-4 resin was a promising CO 2 adsorbent. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45046.
研究领域:
环境化学
·
高分子材料科学
·
气体吸附与分离
·
碳捕集技术
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Yanqi Gu,Shayu Li,Yuehong Xu,Jiaguang Han,Miao Gu,Zhipeng Cai,Yan lv,Guoxin Xie,Tianbao Ma,Jianbin Luo
The influence of an external magnetic field on the picosecond network dynamics of the salt (KCl) solution is investigated by terahertz time-domain spectroscopy. Because hydration changes the motions of water molecules clusters, we test hydration by measuring the change of dielectric loss caused by the slow relaxation of water molecules clusters. We find experimentally that the magnetic field enhances the number of water molecules involved in hydration and the radius of dynamic hydration layer in salt solutions. However, with the increasing concentration, there is a downward in the hydration enhancement per equivalent. Meanwhile, the simulated results show the number of water molecules in hydration layers increases which is consistent with our experimental results. Besides, the simulation reveals that external magnetic field mainly affects the second hydration layer and the stability of water molecules network in hydration layer is enhanced with external magnetic field .
研究领域:
物理化学
·
生物物理
·
分子生物学
·
光谱学
·
溶液化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Hui Jiang,Xiaoyan Liu,Ying Xu,Yongying Jia
As a complex component of crude oil, asphaltenes determine the stability of emulsion . However, the mechanism of asphaltenes stabilize emulsion is still insufficient recognition due to the complexity of the molecular structure of asphaltenes. In this paper, the experiments and dissipative particle dynamics simulations were used to study the interfacial properties of asphaltenes. The adsorption of asphaltenes at the oil–water interface was studied by interfacial tension (IFT) experiments. A realistic molecular structure of asphaltene was constructed on the results of the characterization of the asphaltenes. The effects of asphaltenes concentration, temperature, and shear on the formation and stability of emulsion based on this molecular structure were investigated by simulations. The results show that the IFT decreases as asphaltenes concentration increases, while the droplet size of the emulsion decreases and becomes more uniformly distributed. Increasing the temperature enhances the interfacial activity of the asphaltenes, but also promotes its dissolution in the oil phase, which has a negative effect on reducing the IFT value and the stability of the emulsion. As the shear rate increases , the configuration of the emulsion changes from droplets to ellipsoids and rods, and the structure of the interfacial film is disrupted. This work provides useful insights into the mechanisms of asphaltenes concentration, temperature, and shear on the stability of the emulsion.
研究领域:
石油化学
·
胶体与界面科学
·
流体力学
·
分子模拟
·
能源工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2022
·
IF 3.841
Qi Wang,Shaopeng Fu,Xingyao Yang,Qinghao Sun,Junwei Zhang,Yichun Peng,Rongling Zhang,Zezhou Liang,Jianfeng Li
An organic nitrogen/oxygen-rich polymer (PFN-NDIN) was prepared via Suzuki reaction between 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9,9-bis(3-N,N- dimethylaminopropyl)-9H-fluorene (FNB) and 4,9-dibromo-2,7-bis(3-(dimethyl-amino)propyl)naphthalenediimide (NDINBr 2 ) and utilized as a new inhibitor for HRB400 steels corrosion in alkaline medium of simulated concrete pore solution. The inhibition efficiency of this inhibitor was evaluated by electrochemical techniques. The electrochemical impedance spectroscopy (EIS) results showed that the protective capacity of PFN-NDIN on HRB400 steel increased with increasing concentration to attain 92.85% efficacy with 400 ppm at 288 K. Potentiodynamic polarization (PDP) plots indicated that PFN-NDIN is effective and acts as a hybrid inhibitor. The adsorption behavior of PFN-NDIN was fitted and found to follow the Langmuir isothermal adsorption line, with discussion of the relevant thermodynamic parameters. The effect of temperature on this inhibitor's the rust-inhibiting effect was investigated. The surface was then studied, showing that the interfacial corrosion of HRB400 steel was inhibited by PFN-NDIN molecules. The relationship between PFN-NDIN molecules’ structure and the inhibition efficiency was investigated by quantum chemical calculations. Several parameters were calculated, the findings revealed that the prepared materials correlated well with their electronic contribution capability.
研究领域:
材料腐蚀与防护
·
高分子化学
·
电化学
·
建筑材料科学
·
表面科学
·
量子化学
✓ 已验证
DOI
高影响因子