BIOTECHNOLOGY LETTERS
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2014
·Vol. 37
·期 1
·183-188
·
IF 1.736
He Yu-Cai,Tao Zhi-Cheng,Zhang Dan-Ping,Yang Zhen-Xing,Gao Shan,Ma Cui-Luan
Rhodococcus sp. CGMCC 4911 transformed 1,3-propanediol cyclic sulfate (1,3-PDS) and its derivatives into corresponding diols. Ethylene sulfate, glycol sulfide, 1,3-PDS, and 1,2-propanediol cyclic sulfate were effectively hydrolyzed with growing cells. ( R )-1,2-Propanediol (>99 % e.e. ) was obtained at 44 % yield with growing cells. Glycol sulfide, ethylene sulfate, and 1,3-PDS were converted into the corresponding diols at 94.6, 96.3, and 98.3 %, respectively. Optimal reaction conditions with lyophilized resting cells were 30 °C, pH 7.5, and cell dosage 17.9 mg cell dry wt/ml. 1,3-Propanediol was obtained from 50 mM 1,3-PDS at 97.2 % yield by lyophilized cells after 16 h. Lyophilized cells were entrapped in calcium alginate with a half-life of 263 h at 30 °C, and the total operational time of the immobilized biocatalysts could reach over 192 h with a high conversion rate.
研究领域:
微生物学
·
生物催化
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DOI
PubMed
高影响因子
ACS Catalysis
·
2015
·
IF 9.312
Ruiyan Sun,Tingting Wang,Mingyuan Zheng,Weiqiao Deng,Jifeng Pang,Aiqin Wang,Xiaodong Wang,Tao Zhang
Using cellulosic biomass to synthesize bulk quantities of high-value chemicals is of great interest for developing a sustainable biobased society. Especially, direct catalytic conversion of cellulose to glycols, important building blocks for polymers, remains a grand challenge. Herein, we report the development of a versatile binary nickel–lanthanum(III) catalyst for the conversion of cellulose to both ethylene glycol (EG) and propylene glycol (1,2-PG) in a yield of 63.7%, which is one of the best performances reported for this catalytic reaction. Especially, lanthanum(III) exhibited a high level of activity toward the degradation of cellulose (TON = 339) at a very low concentration (0.2 mmol/L). On the basis of density functional theory calculations and experimental analyses, we addressed a dual route for this catalytic mechanism: a major route involving the selective cracking of sugars into C2 molecules and a minor route involving the hydrogenolysis of sugar alcohols. Lanthanum(III) catalyzes the cleavage of the C2–C3 bond in glucose via sequential epimerization and 2,3-hydride shift reactions to form glycolaldehyde, the precursor of EG.
研究领域:
化学工程
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催化科学
·
生物质能
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2015
·
IF 2.679
Hengde Li,Yongtao Han,Cheng Huang,Chufen Yang
On this paper, experimental (liquid + liquid) equilibrium (LLE) results are presented for systems composed of β-citronellol and aqueous 1-propanol or acetone. To evaluate the phase separation properties of β-citronellol in aqueous mixtures, LLE values for the ternary systems (water + 1-propanol + β-citronellol) and (water + acetone + β-citronellol) were determined with a tie-line method at T = (283.15, 298.15, and 313.15 ± 0.02) K and atmospheric pressure. The reliability of the experimental tie-lines was verified by the Hand and Bachman equations. Ternary phase diagrams, distribution ratios of 1-propanol and acetone in the mixtures are shown. The effect of the temperature on the ternary (liquid + liquid) equilibria was examined and discussed. The experimental LLE values were satisfactorily correlated by extended UNIQUAC and modified UNIQUAC models.
研究领域:
化学工程
·
热力学
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产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 94
·91233-91242
·
IF 3.289
Shanshan Tang,Hailiang Zhao,Lin Du
The hydrogen bonds involving sulfur are generally regarded as weak hydrogen bonds in comparison with conventional ones. The O–H⋯O and O–H⋯S hydrogen bonds in the alcohol–ethylene oxide (EO) and alcohol–ethylene sulfide (ES) complexes in the gas phase have been investigated by FTIR spectroscopy. Three alcohols, methanol (MeOH), ethanol (EtOH) and 2,2,2-trifluoroethanol (TFE) were used as hydrogen bond donors, and comparable OH-stretching red shifts were observed for the complexes with EO and ES as hydrogen bond acceptors. DFT calculations were used to determine the stable structures and interaction energies of the complexes. The equilibrium constant for the complex formation was determined from the experimental integrated absorbance and the computational IR intensity of the OH-stretching transition band of the complex. The effect of CF3 substitution on the hydrogen bond strength in alcohol–EO/ES molecular complexes was investigated and the TFE complexes form much stronger hydrogen bonds than the MeOH and EtOH complexes. Atoms-in-molecules (AIM) analysis revealed that several hydrogen bond interactions were present in the complexes. In addition, the localized molecular orbital-energy decomposition analysis (LMO-EDA) was implemented to analyze the intermolecular interactions. The O–H⋯O and O–H⋯S hydrogen bonds were found to be of similar strength, on the basis of the geometric parameters, binding energies and AIM analysis.
研究领域:
化学
·
物理化学
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2016
·Vol. 18
·期 12
·3607-3613
·
IF 8.506
Guangyi Li,Ning Li,Mingyuan Zheng,Shanshan Li,Aiqin Wang,Yu Cong,Xiaodong Wang,Tao Zhang
A new route for the selective synthesis of renewable 1,3-cyclopentanediol was developed by the aqueous phase rearrangement of furfuryl alcohol to 4-hydroxycyclopent-2-enone followed by hydrogenation. The presence of a small amount of base catalysts is beneficial for the aqueous phase rearrangement of furfuryl alcohol to 4-hydroxycyclopent-2-enone. Such a promotion effect of base catalysts can be rationalized by restraining the generation of levulinic acid which may catalyze the polymerization of furfuryl alcohol. In the hydrogenation of 4-hydroxycyclopent-2-enone to 1,3-cyclopentanediol, an evident solvent effect was noticed. Higher carbon yields of 1,3-cyclopentanediol were obtained when tetrahydrofuran was used as the solvent. In the large scale tests with high initial concentrations of feedstocks, a high overall carbon yield (72.0%) of 1,3-cyclopentanediol was achieved over cheap catalysts (MgAl-HT and RANEY® Ni). As a potential application, 1,3-cyclopentanediol as obtained was successfully used as a monomer in the synthesis of polyurethane.
研究领域:
化学工程
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可再生资源
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工业催化
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产品关联
DOI
高影响因子
PACKAGING TECHNOLOGY AND SCIENCE
·
2017
·Vol. 30
·期 9
·587-600
·
IF 1.32
Haili Wang,Chunxiang Yang,Jing Wang,Mo Chen,Donglei Luan,Li Li
Various studies have provided information on active packaging to prevent food putrefaction effectively . In this work, ethylene–vinyl alcohol copolymer (EVOH) films with geraniol (Ger) and α-terpilenol (Ter) were successfully prepared by extrusion. The mechanical, thermal, oxygen barrier and antimicrobial properties of the packaging films were characterized, and the application of the films in snakehead preservation was examined. Thermogravimetric analysis showed that the addition of Ger and Ter did not decrease the films properties but improved their oxygen barrier property and thermostability. Moreover, the incorporation of Ger and Ter inhibited the growth of Escherichia coli , Salmonella enterica and Listeria monocytogenes . Both of the films, EVOH/Ger (EVOH/Ger) and EVOH/Ter (EVOH/Ter), reduced Salmonella enterica by 2.36 ± 0.17 and 1.91 ± 0.06 log units, respectively. Meanwhile, the effects of EVOH/Ger and EVOH/Ter on quality assessment of snakehead slices were examined through sensory tests and analyses of biochemical indices during refrigerated storage (4°C ± 1°C) for 10 days. Sensory properties, total viable counts, total volatile basic nitrogen, thiobarbituric acid and pH values were evaluated. On eight day, compared with the control fish samples, the total viable counts and total volatile basic nitrogen values cut down 1.98 ± 0.02 log units and 11.3 ± 0.11 mgN/100 g, respectively, for fish samples packaged by EVOH/Ger. The active films containing 6% (wt) Ger and 6% (wt) Ter inhibited the growth of E. coli , S. enterica and L. monocytogenes and effectively extended shelf life by 4–5 days under cold-storage conditions compared with the control group. Copyright © 2017 John Wiley & Sons, Ltd.
研究领域:
食品科学
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包装工程
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产品关联
DOI
高影响因子
MACROMOLECULES
·
2021
·
IF 5.985
Xiaodong Xu,Lujuan Li,Seyed Mohsen Seraji,Lei Liu,Zhen Jiang,Zhiguang Xu,Xin Li,Sheng Zhao,Hao Wang,Pingan Song
Spider silk-inspired hydrogen-bond (H-bond) cross-linking has recently been shown to enable polymers, e.g., poly(vinyl alcohol) (PVA), to achieve high strength in combination with large ductility and great toughness by adding small H-bond cross-linkers. Unfortunately, the correlation of H-bond cross-linking to the microstructure and mechanical performances of the resultant polymers remains unclear. Herein, we prepare strong and tough nanostructured PVA composites with inositol (IN) molecules as cross-linkers. The addition of 1.0 wt % of IN increases the yield strength (σy) of PVA up to 148 MPa (by ∼31%), in combination with appreciable increases in the break strain (by 250%) and toughness (by 3.6-fold) because of dynamic physical cross-linking and crystalline grain refinement. We show that there exists a close but simple correlation between the H-bond cross-linking density (ne) and σy, the chain movement (e.g., glass transition temperature (Tg), relaxation activation energy (Ea)) and the crystalline grain size (L), namely, σy ∝ ne, Tg, Ea, and 1/L. This work casts light on the governing effect of H-bonding cross-linking on the microstructure and mechanical properties of PVA and unveils its correlation to mechanical properties, chain dynamics, and crystallization for the first time. These exciting findings open up many new opportunities for creating strong, tough, and ductile polymeric materials.
研究领域:
材料科学
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生物仿生学
·
高分子化学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Jian Zhang,Kai Shi,Zhe An,Yanru Zhu,Xin Shu,Hongyan Song,Xu Xiang,Jing He
Dehydrogenation coupling of ethanol to n-butanol has received much attention due to the wide application of n-butanol. Highly selective butanol production from ethanol remains a challenge due to competitive reactions in the dehydrogenation and/or condensation and great difficulty in ethanol dehydrogenation. This work reports a synergistic catalysis between layered double hydroxide (LDO), an acidic–basic support, and supported Ag particles for the dehydrogenation coupling of ethanol to n-butanol. A selectivity of up to 77% toward n-butanol with an ethanol conversion of 23.2%, among impressive levels reported till now, has been achieved at 350 °C, 0.1 MPa. A selectivity of up to 60% toward n-butanol with an ethanol conversion of 45%, the highest selectivity at an ethanol conversion of >45% reported till now, has been achieved at 250 °C, 2 MPa. A synergistic catalysis between the acid–base sites of the LDO surface and supported Ag particles have been revealed to contribute the excellent butanol selectivity: basic sites promote adsorption and subsequent dehydrogenation of ethanol on Ag particles; in addition to the promotion from Ag, the following aldol condensation is boosted by acid–base cooperation.
研究领域:
催化化学
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材料科学
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能源化学
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产品关联
DOI
高影响因子
COLD REGIONS SCIENCE AND TECHNOLOGY
·
2022
·
IF 4.427
Haoxia Ma,Haiyan Ma,Hongfa Yu,Bo Da,Wei Gong,Na Zhang
Ethylene glycol (EG) deicer and propylene glycol (PG) deicer were frequently used as the aircraft de-icing fluids in cold region. In this paper, the icing pressure ( I p ), icing volume expansion rate (Δ V P ), freezing point ( T 0 ) and under-cooling ( △T ) of aircraft deicers with different concentrations were investigated, and the above indicators of aircraft deicers were also compared with that of water and NaCl deicers. The results showed that the icing volume expansion of deicers was the direct cause of icing pressure. During the cooling process, values of I p and Δ V P firstly increased sharply, then slowly, and finally became stable. The stabilized values of I p and Δ V P decreased with concentration. The stabilized I p value of EG deicer was slightly higher than that of 3.5% NaCl deicer and far greater than 3.5% PG deicer. Of all the tested deicers, the stabilized Δ V P value of NaCl deicer was the highest and that value of EG deicer was close to that of PG deicer. The results further confirmed the feasibility of using impulse of icing pressure as the indicator to evaluate the freeze-thaw deterioration to concrete.
研究领域:
材料科学
·
航空工程
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Kang Chen,Mili Liu,Liuzhang Ouyang,Hui Wang,Jiangwen Liu,Min Zhu
Hydrolysis of LiBH 4 (LB in short) is considered as a potential means of releasing the hydrogen stored in the hydride and the water. However, the hydrolysis of LB occurs only above 0 °C and efficient catalysts are required to accelerate the hydrogen kinetics. Here, we demonstrate an efficient non-catalytical hydrogen generation system that enables H 2 production of LB over a wide range of temperatures with methanol (referred to MeOH), ethylene glycol, and MeOH/water mixtures as reaction solvents. The results indicate that the hydrogen kinetics of LB is controllable by MeOH dose, MeOH species, reaction temperature, and solution components. For instance, the hydrogen evolution rate could be accelerated from 266 to 515 mL H2 min −1 g −1 (per unit weight of LB) with a H 2 yield up to 93% by tailoring the dose of methanol at 25 °C. Notably, the glycolysis kinetics is much faster than that for the methanolysis of LB, delivering a hydrogen rate varying from 523 to 10,125 mL H2 min −1 g −1 . By optimizing reaction conditions, a gravimetric hydrogen density of ~4.6 wt% H 2 was realized in the LB-MeOH system. Interestingly, the methanolysis/glycolysis products of LB can spontaneously convert into MeOH and hydrated byproduct (LiBO 2 ‧2H 2 O) by reacting with water, and MeOH may be separated and reused as an intermediate. Here, LiBO 2 ‧2H 2 O can be easily regenerated back to LB by ball milling with Mg under ambient conditions. Thus, a hydrogen cycle combining hydrogen generation and storage in a closed material cycle is achieved, which may lay the foundation for developing practical hydrogen sources for mobile/portable applications.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2019
·Vol. 11
·期 12
·2096
·
IF 3.164
Wenjie Chen,Jiao Ding,Xuming Yan,Wei Yan,Ming He,Guoqiang Yin
The use of waste plant protein obtained from underutilized and non-food-producing plants may be a promising strategy in the development of bioactive packaging. A series of blend films were prepared by casting from cottonseed protein (CP) and poly(vinyl alcohol) (PVA) and modified with different plasticizers. The morphology, structure, and crystallinity of each of the blend films were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. CP and PVA were found to be compatible in the appropriate ratios, and the CP/PVA blend films were partially crystalline. We compared the effects that four plasticizers, i.e., glycerol, triethanolamine (TEA), ethylene glycol, and polyethylene glycol, had on the performance of the CP/PVA blend films. Plasticizers altered the degree of interaction between CP and PVA, which changed the secondary structure of the CP but had little effect on the crystallinity of CP/PVA blend films. Among the different plasticizers tested, TEA was the most efficient at improving the elongation at the break, tensile strength, and oxygen barrier properties of the CP/PVA blend films. Such CP/PVA blend films plasticized using TEA can, therefore, be considered emerging and promising plastics for potential applications in food packaging and flower planting applications.Keywords:cottonseed protein;poly (vinyl alcohol);plasticizer;blend films;triethanolamine
研究领域:
材料科学
·
生物技术
·
包装工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Catalysis
·
2023
·
IF 12.9
Shaoxia Guo,Zhuoshi Li,Rui Yin,Jianbao Li,Zhuang Zeng,Zhiwei Hu,Guangyuan Luo,Jing Lv,Shouying Huang,Yue Wang,Xinbin Ma
Higher alcohol synthesis (HAS) from syngas is highly attractive but still challenging due to the complexity of the reaction system and the difficulty in modulating the carbon number distribution of products, especially in improving the selectivity toward ethanol or short-chain alcohols over a single catalyst. Herein, we propose a CoMnOx nanocomposite catalyst with the Co/Mn molar ratio of 1/2 prepared by the facile sol–gel method and found that it could selectively produce short-chain alcohols in the HAS. The C2-5OH proportion in the total alcohol reached 75.5 C%, in which the ethanol proportion was as high as 48.0 C%, breaking through the Anderson-Schulz–Flory distribution and outperforming most of the reported cobalt-based catalysts for HAS. Multiple characterizations and contrast experiments indicated that oxygen vacancies in MnOx that formed during reduction and reaction can dissociate CO but are inactive in C–C coupling, thus generating lots of CHx* monomers. The CHx* intermediates could react with the CO* species adsorbed on the neighboring Co2C species, greatly stimulating the production of ethanol. It is also demonstrated that the oxygen vacancies possibly facilitated the carbonization of cobalt and enhanced the alcohol selectivity, while the untransformed CoxMn1–xO was not active in the reaction. These findings may provide potentials in designing catalysts for highly selective production of ethanol and short-chain products in HAS from syngas.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）