JOURNAL OF POLYMER RESEARCH
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2024
·Vol. 31
·期 10
·1-11
·
IF 2.6
Chen Yueqing,Huang Zhenhong,Chen Haijian,Ai Jiaoyan,Song Lina,Liu Baohua
Waterborne polyurethanes emulsions (WPU) based on polyethylene carbonate diol (PECD) were synthesized, characterized and modified by polypropylene carbonate diol (PPCD) and organosilicon KH-792. The mechanical, thermal and hydrolysis resistance properties of waterborne polyurethanes were comprehensively investigated. The results show that PECD based WPU has very excellent mechanical properties. The tensile strength and the elongation at break the PU was up to 73 MPa and 1040%, which was much higher than that reported for similar types of PPCD-based WPU. It was found that water absorption of PECD based WPU can be decreased dramatically, from 40.9% to 21.1%, after 50% PECD was replaced by PPCD, while tensile strength only decreased from 73.0 MPa to 63.4 MPa. The addition of KH-792 has great influence on PECD based WPU, when 1% KH-792 was added, the water absorption rate decreased from 21.1% to 11.88%, the mechanical strength remained at 63.3 MPa, the WPU film remained transparent after soaking in 80 ℃ hot water for 4 h.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2023
·
IF 6.1
Bin Wu,Shiyu Wang,Yunjian Ma,Shuguang Yuan,Frank Hollmann,Yonghua Wang
Alcohol oxidases (AOxs) catalyze the aerobic oxidation of alcohols to the corresponding carbonyl products (aldehydes or ketones), producing only H2O2 as the byproduct. The majority of known AOxs, however, have a strong preference for small, primary alcohols, limiting their broad applicability, e.g., in the food industry. To broaden the product scope of AOxs, we performed structure-guided enzyme engineering of a methanol oxidase from Phanerochaete chrysosporium (PcAOx). The substrate preference was extended from methanol to a broad range of benzylic alcohols by modifying the substrate binding pocket. A mutant (PcAOx-EFMH) with four substitutions exhibited improved catalytic activity toward benzyl alcohols with increased conversion and kcat toward the benzyl alcohol from 11.3 to 88.9% and from 0.5 to 2.6 s–1, respectively. The molecular basis for the change of substrate selectivity was analyzed by molecular simulation.
研究领域:
生物化学
·
酶学
·
食品科学
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DOI
PubMed
高影响因子
Separations
·
2024
·Vol. 11
·期 9
·276
·
IF 2.5
Kaidierya Abudureheman,Qinglin Wang,Hao Zhang,Xingchu Gong
The Analytical Quality by Design (AQbD) concept was adopted to establish a quantitative analysis of multi-components with a single marker (QAMS) method for industrial lanolin alcohol, targeting cholesterol, lanosterol, and 24,25-dihydrolanosterol. The potential critical method parameters (CMPs) were identified as column temperature, flow rate, and gradient. Definitive screening design and statistical modeling were employed to optimize the gradient conditions of the mobile phase, column temperature, and flow rate. The Method Operable Design Region (MODR) was determined using a risk-based quantification approach. The robustness was assessed using a Plackett–Burman experimental design, followed by methodological validation. Optimal analytical conditions were as follows: acetonitrile (B)—water (A) mobile phase system; flow rate of 1.58 mL/min; detection wavelength of 205 nm; injection volume of 10 µL; and column temperature of 37 °C. A gradient elution program was implemented as follows: 0–19.0 min, 90.5% B; 19.0–25.0 min, 90.5–100% B; and 25.0–55.0 min, 100% B. Cholesterol served as an internal standard for quantifying lanosterol and 24,25-dihydrolanosterol, with relative correction factors of 0.4227 and 0.8228, respectively. This analytical method utilized only the cholesterol reference substance as an internal standard to quantify the content of cholesterol, lanosterol, and 24,25-dihydrolanosterol in industrial lanolin alcohol. It reduced the testing costs and enhanced efficiency, making it potentially suitable for widespread adoption in lanolin alcohol processing industries.
研究领域:
分析化学
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生物医学
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产品关联
DOI
高影响因子
Chemical Engineering and Processing-Process Intensification
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2024
·
IF 3.8
Zifei Yan,Grace Dai Zhen Lee,Jian Deng,Guangsheng Luo
The synthesis of terminal epoxides, which are vital components in pharmaceuticals and resins, often involves dehydrochlorination of β-chlorohydrins. Although intrinsic kinetics indicate that the dehydrochlorination reaction in the presence of sodium hydroxide could be very rapid, the practical implementation could always be hindered by long reaction time and low conversion rate. Extended contact between the product and the alkaline solution can lead to hydrolysis of the epoxy group, thus necessitating the process intensification to realize higher production efficiency and selectivity. Here, by characterizing thermodynamic equilibrium data and in-situ recording of the reaction that proceeded in a constant interphase reactor, the heterogeneous dehydrochlorination is demonstrated to occur primarily in the organic phase, and the overall reaction rate depends on the equilibrium concentration of sodium alkoxides. This finding, which is fundamentally different from the traditional view that chlorohydrin is first dissolved in the aqueous phase and then reacts with NaOH, leads us to use inert alcohols to assist in the extraction of NaOH. Based on this method, the reaction time can be reduced over 80 % both in batch and continuous reactors. Besides, the method is demonstrated to be effective in the dehydrochlorination of five different long-chain β-chlorohydrins.
研究领域:
化学工程
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有机合成
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DOI
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2019
·Vol. 34
·期 4
·945-949
·
IF 0.605
Kang Jiaqing,Chen Wei,Yao Yuan,Jin Yanqiao,Cheng Xiansu,Lü Qiufeng
Cassava residue was liquefied by using ethylene glycol (EG), ethylene carbonate, propylene carbonate and polyethylene glycol (molecular weight: 400 g/mol) as the liquefaction reagent respectively at the temperature of 130–170 °C with sulfuric acid as the catalyst. The influences of liquefaction parameters, such as the type of liquefaction reagents, mass ratio of EG/cassava residue, liquefaction temperature and time on the properties of the products were discussed. The optimum liquefaction conditions were obtained when the mass ratio of EG/cassava residue was 6:1 ( w/w ), the liquefaction temperature was 150 °C, the liquefaction time was 3 h and the mass fraction of concentrated sulfuric acid/EG was 2.5wt%. The hydroxyl numbers and residue content of the liquefied products at optimal conditions were 1 137 mgKOH/g and 0.43%, respectively. FT-IR spectrum showed that the liquefaction product of cassava residue was polyether polyol and could be used to prepare polyurethane material or alkyd resins.
研究领域:
生物化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2024
·
IF 5.6
Ziye Zhang,Peng Zhang,Hao Chen,Han Wu,Limin Geng,Wenbo Zhang,Zhanming Chen,Donghui Qi,Jianming Cao,Biao Wang
The rapid increase in automobile ownership has brought about an increase in pollutant emissions, the blending of alcohols can effectively reduce conventional pollutant emissions from diesel engines. However, alcohols have poor inter-solubility with diesel fuel. This study investigates the effects of blending different alcohols on the spray and combustion characteristics of diesel, with biodiesel as the cosolvent. The results show that among the three alcohols, blending methanol has the best improvement in the gas-liquid phase spray characteristics, followed by ethanol and propanol. The GL-SCA and GL-SPA of the methanol blends are 8.2 % and 2.3 % larger than those of the ethanol blends, and 19 % and 11.9 % larger than those of the propanol blends, respectively. Among the four fuels, fuel blended with methanol emits the least normalized sum KL, 45 % less than that of diesel, 23.8 % less than that of ethanol blended fuel, and 35.3 % less than that of propanol blended fuel.
研究领域:
能源与燃料
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光学研究
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发动机排放控制
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DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2022
·
IF 3.841
Shuai Zhang,Xiaoyu Fan,Shuhan Jiang,Rentian Guan,Xiaodong Shao,Shuhao Wang,Qiaoli Yue
Trace moisture was firstly measured in methanol, ethanol and n-propanol at room temperature. The N, P-codoped carbon dots (CDs) were prepared by one pot solvothermal method, which displayed solvent-dependent fluorescence. The N, P-codoped CDs exhibited green fluorescence, with the quantum yields (QY) of 27.9%, 37.4%, 26.2% and 2.3% in methanol, ethanol, n-propanol and water, respectively. Based on the hydrogen bond interactions between the protic solvents and the N, P-codoped CDs, with the water content increased, the fluorescence intensity of N, P-codoped CDs gradually decreased in methanol, ethanol and n-propanol. The decrement in the fluorescence intensity is linearly related to the water content within the content range of 2% to 8%, 0.04% to 5% and 0.04% to 1.0%, with a limit of detection of 0.22%, 0.009% and 0.021% in methanol, ethanol and n-propanol, respectively. Therefore, the present system has a prospective value for the application in the determination of trace water in the relevant fields.
研究领域:
分析化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Weibiao Du,Xiaopo Wang
In this work, the volumetric and viscometric properties of the mixtures of methyl decanoate with 1-propanol, 1-butanol, and 1-pentanol were investigated from 298.15 K to 333.15 K. The density data of the mixtures were obtained based on the vibrating-tube densimeter , and the kinematic viscosities of the mixtures were measured using the Ubbelohde capillary viscometer . Based on the experimental data, the excess molar volumes and viscosity deviations were calculated and correlated with the Redlich–Kister equation. In addition, the McAllister four-body model, Frenkel model, Grunberg-Nissan model, and Heric's model were used to correlate the viscosities of the mixtures.
研究领域:
物理化学
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热力学
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流体性质
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燃料化学
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溶液化学
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DOI
高影响因子
Catalysis Science & Technology
·
2019
·Vol. 10
·期 1
·70-78
·
IF 5.726
Zeyu Yang,Hengwei Fu,Wenjie Ye,Youyu Xie,Qinghai Liu,Hualei Wang,Dongzhi Wei
Alcohol dehydrogenases (ADHs) together with the economical substrate-coupled cofactor regeneration system play a pivotal role in the asymmetric synthesis of chiral alcohols; however, severe challenges concerning the poor tolerance of enzymes to 2-propanol and the adverse effects of the by-product, acetone, limit its applications, causing this strategy to lapse. Herein, a novel ADH gene smadh2 was identified from Stenotrophomonas maltophilia by traditional genome mining technology. The gene was cloned into Escherichia coli cells and then expressed to yield SmADH2. SmADH2 has a broad substrate spectrum and exhibits excellent tolerance and superb activity to 2-propanol even at 10.5 M (80%, v/v) concentration. Moreover, a new thermostatic bubble column reactor (TBCR) system is successfully designed to alleviate the inhibition of the by-product acetone by gas flow and continuously supplement 2-propanol. The organic waste can be simultaneously recovered for the purpose of green synthesis. In the sustainable system, structurally diverse chiral alcohols are synthesised at a high substrate loading (>150 g L−1) without adding external coenzymes. Among these, about 780 g L−1 (6 M) ethyl acetoacetate is completely converted into ethyl (R)-3-hydroxybutyrate in only 2.5 h with 99.9% ee and 7488 g L−1 d−1 space–time yield. Molecular dynamics simulation results shed light on the high catalytic activity toward the substrate. Therefore, the high 2-propanol tolerance SmADH2 with the TBCR system proves to be a potent biocatalytic strategy for the synthesis of chiral alcohols on an industrial scale.
研究领域:
生物化学
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工业生物技术
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2017
·
IF 3.648
Junwei Zhang,Shuai Yang,Hang Li,Pengpeng Yu,Li Xu,Guoji Liu
The solubility of 1,6-Hexanediol in (methanol + dimethyl adipate (DMA)), ( n -butanol + DMA) binary solvents was measured by the dynamic method under 0.1 MPa. The studies were carried out at different mass fractions of methanol or n -butanol from 283.15 K to 303.15 K. The solubility of 1,6-Hexanediol in binary solvents increases with increasing temperature and mass fraction of methanol or n -butanol. In a fixed temperature and fixed mass fraction of methanol or n -butanol, the solubility of 1,6-Hexanediol in (methanol + DMA) is greater than in ( n -butanol + DMA). In addition, the experimental solubility data were correlated by Jouyban–Acree model, Van't Hoff–Jouyban–Acree model, modified Apelblat–Jouyban–Acree model and Sun model, in which the Sun model shows the best agreement with the experimental solubility data. The maximum of relative average deviation ( RAD ) and the root-mean-square deviation ( RMSD ) between the experimental and calculated solubility were 5.85 × 10 − 2 and 3.80 × 10 − 2 , respectively. Additionally, the thermodynamic properties (including enthalpy, Gibbs energy and entropy) were also obtained, and the results show that the dissolution of 1,6-Hexanediol in the two binary solvents is an endothermic process.
研究领域:
物理化学
·
热力学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Juncheng Yang,Yihong Jia,Benhua Huang,Xiaoyong Li,Lina Guo,Aqun Zheng,Rafael Luque,Yang Sun
1,4-Sorbitan and 1,4-mannitan are important precursors for the synthesis of detergents and pharmaceuticals, derived from mono-dehydration of sugar alcohols (d-sorbitol and d-mannitol). In order to improve mono-dehydration selectivity, functionalized CeO2/SBA-15 materials were synthesized and employed as dehydration catalysts. Characterization revealed that all synthetic catalysts contain cerium dioxide nanoparticles with sizes below 10 nm. All prepared catalysts provided 1,4-sorbitan or 1,4-mannitan as the major dehydration products in water at room temperature, with catalysts being nicely active and stable after several reuses.
研究领域:
催化化学
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材料科学
·
绿色化学
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2019
·
IF 3.571
Shanshan Wang,Kai Ye,Tong Shu,Xiuwen Tang,Xiu Jun Wang,Songbai Liu
In this study, incorporation of gallic acid into typical phytosterols (β-sitosterol and stigmasterol) through Steglich esterification was optimized employing the protection and deprotection strategy. A novel mechanism leading to side esterification was discovered. Complication of the phenolic hydroxyl groups and side reactions were successfully reduced under the optimized conditions. The structural identity and purity of galloyl stigmasterol and galloyl β-sitosterol were confirmed by NMR, FT-IR, and HPLC-MS. Evaluation of galloyl β-sitosterol and galloyl stigmasterol revealed their excellent antioxidant and cholesterol-reducing activities. Significant enhancement of cholesterol-reducing activity by galloylation was unveiled especially for β-sitosterol. Galloyl β-sitosterol had slightly better antioxidant activity at ambient temperature and better cholesterol-reducing activity. Molecular modeling suggested that a subtle difference of galloyl β-sitosterol and galloyl stigmasterol in activities could be attributed to variation of molecular rigidity and conformation. The excellent properties of galloyl β-sitosterol and galloyl stigmasterol suggested their great potential application in the food industry.
研究领域:
有机化学
·
药学
·
食品科学
·
生物化学
✓ 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）