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Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

《环境科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 503-509 doi: 10.1007/s11783-013-0540-1

摘要： A mathematical model for the transport of Ce(IV) from hydrochloric acid solutions through dispersion flat combined liquid membrane (DFCLM) with contain 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester (P507) as the carrier, dissolved in kerosene as the membrane solution have been studied. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick’s second law. The equations for transport velocity are derived considering the diffusion of P507 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce(IV) and the carrier to take place only at the solvent–aqueous interfaces. Model concentration profiles are obtained for the Ce(IV), from which extraction velocities are predicted. The experimental and simulated Ce(IV) extractions showed similar tendencies for a high Ce(IV) concentration and acidity case.The model results indicate that high initial Ce(IV) concentrations and acidity both have detrimental effects on Ce(IV) extraction and stripping. The diffusion coefficient of Ce(IV) in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and the values are 6.31 × 10 m ·s and 31.2 μm, respectively. The results are in good agreement with experimental results.

关键词： Dispersion flat combined liquid membrane (DFCLM)     dispersion phase     feed phase     2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester     Ce (IV)    

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Effect of exhaust gas recirculation and ethyl hexyl nitrate additive on biodiesel fuelled diesel engine

K. VENKATESWARLU, B. S. R MURTHY, V. V. SUBBARAO, K. Vijaya KUMAR

《能源前沿（英文）》 2012年 第6卷 第3期   页码 304-310 doi: 10.1007/s11708-012-0195-9

摘要： Cetane improvers reduce the ignition delay, which in turn reduces the combustion temperatures thereby reduce NO emissions. Exhaust gas recirculation (EGR) proved to be an effective way to reduce the NO emissions. In this present experimental work, a combination of exhaust gas recirculation and cetane improver ethyl hexyl nitrate (EHN) is used to investigate the performance and exhaust emissions of a single cylinder four stroke naturally aspirated direct injection and air cooled diesel engine. Test results show that the brake thermal efficiency increases with the increase in the percentage of EGR which is accompanied by a reduction in brake specific fuel consumption and exhaust gas temperatures, and that bio-diesel with cetane improver under 20% EGR reduces NO emissions by 33% when compared to baseline fuel without EGR. However carbon monoxide (CO), hydro carbon (HC) and smoke emissions increase with an increase in percentage of EGR.

关键词： additive     exhaust gas recirculation (EGR)     emissions     ethyl hexyl nitrate (EHN)     performance    

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Supercritical carbon dioxide extraction of CLA-ethyl ester

Yingdi CHEN, Peng XU, Jian CHENG

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 102-106 doi: 10.1007/s11705-010-0536-3

摘要： Supercritical carbon dioxide (SC-CO ) extraction of Conjugated linoleic acid (CLA) ethyl ester was investigated at pressures in the range of 9 to 10.5 MPa and temperature gradients ranging from 0°C to 21°C. The content of CLA-ethyl ester in the fraction was analyzed with gas chromatography (GC). The experimental results indicated that the rate of extraction would rise with the increase of pressure when temperature gradient was given. Moreover, the extraction pressure had insignificant influence on the selectivity of CLA-ethyl ester in SC-CO . When pressure was fixed, setting certain temperature gradient can improve the selectivity of CLA-ethyl ester in SC-CO , and CLA-ethyl ester can be concentrated more effectively than without a temperature gradient. The acid value and peroxide value of the fractions were reduced obviously, compared to the raw material. The optimal condition is pressure at 10 MPa and temperature gradient at 11°C.

关键词： supercritical carbon dioxide     extraction     CLA-ethyl ester     temperature gradient    

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Synthesis and bulk polymerization kinetics of monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethylester

Haibo ZHANG,Yanping YANG,He LIU,Jie SONG,Shibin SHANG,Zhanqian SONG

《农业科学与工程前沿（英文）》 2017年 第4卷 第1期   页码 97-105 doi: 10.15302/J-FASE-2016115

摘要： A bulk polymerization monomer dehydro- abietic acid-(2-acryloyloxy-ethoxy)-ethyl ester (DHA-DG-AC) was synthesized from dehydroabietic acid (DHA). The chemical structure of DHA-DG-AC was characterized by H NMR, C NMR, MS and FT-IR. The kinetics of the bulk polymerization of DHA-DG-AC was investigated by Differential Scanning Calorimeter (DSC). Two kinds of kinetic model (nth-order model and autocatalytic model) were used to investigate the polymerization process. The results showed that the experimental DSC curves were consistent with the computational data generated by the autocatalytic kinetic model, and the value of was 95.73 kJ·mol .

关键词： dehydroabietic acid     bulk polymerization     kinetics     autocatalytic kinetic model    

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Toughening of vinyl ester resins by two-dimensional MXene nanosheets

《化学科学与工程前沿（英文）》   页码 1651-1658 doi: 10.1007/s11705-022-2208-5

摘要： Two-dimensional nanosheets are highly effective tougheners for vinyl ester resins. The toughening effect is related to the high specific surface area and unique two-dimensional planar structure of the nanosheets. In this study, a coupling agent γ-(2,3-epoxypropoxy) propytrimethoxysilane (Kh-560) was used to modify MXene nanosheets (M-MXene) for use in toughening vinyl ester resin. The mechanical properties, including the tensile strength, flexural strength, Young’s modulus and elongation, of neat vinyl ester resin and vinyl ester resin modified with MXene and M-MXene were investigated. The results showed that modification significantly improved the mechanical properties of the vinyl ester resin. The tensile and flexural strengths of the MXene-nanosheet-modified vinyl ester resin were 27.20% and 25.32% higher, respectively, than those of the neat vinyl ester resin. The coupling agent improved the interfacial compatibility between the MXene nanosheets and vinyl ester resin, which resulted in the tensile and flexural strengths of the M-MXene-nanosheet-modified vinyl ester resin being 52.57% and 54.60% higher, respectively, than those of the neat vinyl ester resin for a loading quantity of nanosheets of only 0.04 wt %, which is economically viable. The main mechanisms by which the nanosheets toughen the resin are crack deflection and crack pinning.

关键词： MXene nanosheets     2D material     vinyl ester resin     modification     coupling agent    

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Catalytic oxidation of carbon monoxide, toluene, and ethyl acetate over the

Zhidan Fu, Lisha Liu, Yong Song, Qing Ye, Shuiyuan Cheng, Tianfang Kang, Hongxing Dai

《化学科学与工程前沿（英文）》 2017年 第11卷 第2期   页码 185-196 doi: 10.1007/s11705-017-1631-5

摘要： The Pd catalyst supported on cryptomelane-type manganese oxide octahedral molecular sieve (OMS-2) were prepared. The effect of Pd loading on the catalytic oxidation of carbon monoxide, toluene, and ethyl acetate over Pd/OMS-2 has been investigated. The results show that the Pd loading plays an important role on the physicochemical properties of the Pd/OMS-2 catalysts which outperform the Pd-free counterpart with the 0.5Pd/OMS-2 catalyst being the best. The temperature for 50% conversion was 25, 240 and 160 °C, and the temperature for 90% conversion was 55, 285 and 200 °C for oxidation of CO, toluene, and ethyl acetate, respectively. The low-temperature reducibility and high oxygen mobility of Pd/OMS-2 are the factors contributable to the excellent catalytic performance of 0.5Pd/OMS-2.

关键词： cryptomelane-type manganese oxide octahedral molecular sieve     oxygen mobility     reducibility     carbon monoxide oxidation     volatile organic compound combustion    

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Energy-efficient recovery of tetrahydrofuran and ethyl acetate by triple-column extractive distillation

Ao Yang, Yang Su, Tao Shi, Jingzheng Ren, Weifeng Shen, Teng Zhou

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 303-315 doi: 10.1007/s11705-021-2044-z

摘要： An energy-efficient triple-column extractive distillation process is developed for recovering tetrahydrofuran and ethyl acetate from industrial effluent. The process development follows a rigorous hierarchical design procedure that involves entrainer design, thermodynamic analysis, process design and optimization, and heat integration. The computer-aided molecular design method is firstly used to find promising entrainer candidates and the best one is determined via rigorous thermodynamic analysis. Subsequently, the direct and indirect triple-column extractive distillation processes are proposed in the conceptual design step. These two extractive distillation processes are then optimized by employing an improved genetic algorithm. Finally, heat integration is performed to further reduce the process energy consumption. The results indicate that the indirect extractive distillation process with heat integration shows the highest performance in terms of the process economics.

关键词： extractive distillation     solvent selection     conceptual design     process optimization     heat integration    

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A comparison of the biological activities of ethyl acetate fractions from the stems and leaves of

Zhaolei WANG, Kai JIANG, Qinchao DING, Shujun LIU, Xiaobing DOU, Bin DING

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 505-512 doi: 10.15302/J-FASE-2019271

摘要：

Pursh (PCP) is a popular traditional medicinal plant in China, widely used for the treatment of a variety of liver diseases. Although it has been long recognized that the main active elements of PCP are contained in ethyl acetate fraction (EAF), little is known so far in terms of the relative effectiveness of EAF derived from the stems versus leaves of this plant. In the current study, we prepared EAF by reflux extraction and sequential extraction from the stems (SEAF) and leaves (LEAF) of PCP and tested their hepatoprotective efficacies. The extract rates and flavonoid contents of LEAF were higher than those of SEAF. EAFs (>50 μg·mL ) prevented lipid accumulation in cells and protected against lipotoxicity injury when the concentration exceeded 25 μg·mL . More than 95% free radicals released by 2,2-diphenyl-1-picrylhydrazyl (DPPH) were eliminated by 25 μg·mL SEAF and 50 μg·mL LEAF, respectively. Further, EAFs (25 μg·mL ) also showed protective antioxidant effects, with the activity of LEAF being significantly higher than that of SEAF. EAFs (10 mg·mL ) also showed similar unspecific bacteriostatic activity. In comparison with SEAF, LEAF contained more flavonoids and had a higher anti-oxidation capability and for these reasons we suggest it should be better for clinical use.

关键词： antibacterial     anti-oxidation     lipid accumulation     lipotoxicity     Penthorum chinense Pursh    

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Unravelling the bottleneck of phosphonic acid anchoring groups aiming toward enhancing the stability

《化学科学与工程前沿（英文）》 2022年 第16卷 第7期   页码 1060-1078 doi: 10.1007/s11705-021-2117-z

摘要： Novel near-infrared sensitizers with different anchoring groups aiming toward improved stability and efficiency of dye-sensitized solar cells were synthesized. Adsorption of these dyes on the mesoporous TiO2 surface revealed the dye adsorption rate of –CH=CH–COOH (SQ-139)>–CH=C(CN)COOH (SQ-140)>–PO3H2 (SQ-143)>–CH=C(CN)PO3H2 (SQ-148)>–CH=C(CN)PO3H–C2H5 (SQ-157)>–PO3H–C2H5 (SQ-151)>–CH=CH–COOH(–PO3H2) (SQ-162). The binding strength of these dyes on mesoporous TiO2 as investigated by dye desorption studies follows SQ-162>SQ-143>SQ-148>SQ-139>SQ-157~SQ-151>SQ-140 order. The acrylic acid anchoring group was demonstrated to be an optimum functional group owing to its fast dye adsorption rate and better binding strength on TiO2 along with good photoconversion efficiency. Results of dye binding on TiO2 surface demonstrated that SQ-162 bearing double anchoring groups of phosphonic and acrylic acid exhibited>550 times stronger binding as compared to dye SQ-140 having cyanoacrylic acid anchoring group. SQ-140 exhibited the best photovoltaic performance with photon harvesting mainly in the far-red to near-infrared wavelength region having short circuit current density, open-circuit voltage and fill factor of 14.28 mA·cm–2, 0.64 V and 0.65, respectively, giving the power conversion efficiency of 5.95%. Thus, dye SQ-162 not only solved the problem of very poor efficiency of dye bearing only phosphonic acid while maintaining the extremely high binding strength opening the path for the design and development of novel near-infrared dyes with improved efficiency and stability by further increasing the π-conjugation.

关键词： anchoring groups     adsorption behaviour     dye-binding strength     squaraine dyes     dye-sensitized solar cells    

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Proline-2′-deoxymugineic acid, a phytosiderophore analog, drives beneficial rhizobacterial community

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023531

摘要：

● Proline-2′-deoxymugineic (PDMA) significantly altered the bacterial community in the peanut rhizosphere.

关键词： Beneficial rhizobacteria recruitment     peanut     plant-soil micronutrition enhancement     proline-2′-deoxymugineic acid     stable microbial network    

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Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 80-84 doi: 10.1007/s11705-008-0017-0

摘要： 2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature, solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and triethylamine as catalyst, (I) : (II) : (triphenylphosphine) = 1.0 : 1.0 : 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional processes because of its easy handling, high yield and low cost.

关键词： 5-Amino-1     2     4-thiadiazol-3-yl     1     2-dichloroethane     important intermediate     2-benzothiazolyl thioester     temperature    

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Investigation of the effects of humic acid and H 2 O 2 on the photocatalytic degradation of atrazine

Chao QIN, Shaogui YANG, Cheng SUN, Jia ZHOU, Manjun ZHAN, Rongjun WANG, Huanxing CAI,

《环境科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 321-328 doi: 10.1007/s11783-010-0238-6

摘要： A solution of atrazine in a TiO suspension, an endocrine disruptor in natural water, was tentatively treated by microwave-assisted photocatalytic technique. The effects of mannitol, oxygen, humic acid, and hydrogen dioxide on the photodegradation rate were explored. The results could be deduced as follows: the photocatalytic degradation of atrazine fits the pseudo-first-order kinetic well with = 0.0328 s, and ·OH was identified as the dominant reactant. Photodegradation of atrazine was hindered in the presence of humic acid, and the retardation effect increased as the concentration of humic acid increased. HO displayed a significant negative influence on atrazine photocatalysis efficiency. Based on intermediates identified with gas chromatography-mass spectrometry (GC-MS) and Liquid chromatography-mass spectrometry (LC-MS/MS) techniques, the main degradation routes of atrazine are proposed.

关键词： atrazine     retardation effect     photocatalysis     TiO2    

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PGUS1 hybrid nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid3-O-mono-β-D-glucuronide preparation

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 554-562 doi: 10.1007/s11705-019-1834-z

摘要： Glycyrrhetinic acid 3- -mono- -D-glucuronide (GAMG), an important pharmaceutical intermediate and functional sweetener, has broad applications in the food and medical industries. A green and cost-effective method for its preparation is highly desired. Using site-directed mutagenesis, we previously obtained a variant of -glucuronidase from Li-3 (PGUS1), which can specifically transform glycyrrhizin (GL) into GAMG. In this study, a facile method was established to prepare a CaHPO -PGUS1 hybrid nanoflower for enzyme immobilization, based on protein-inorganic hybrid self-assembly. Under optimal conditions, 1.2 mg of a CaHPO -PGUS1 hybrid nanoflower precipitate with 71.2% immobilization efficiency, 35.60 mg∙g loading capacity, and 118% relative activity was obtained. Confocal laser scanning microscope and scanning electron microscope results showed that the enzyme was encapsulated in the CaHPO -PGUS1 hybrid nanoflower. Moreover, the thermostability of the CaHPO -PGUS1 hybrid nanoflower at 55°C was improved, and its half-life increased by 1.3 folds. Additionally, the CaHPO -PGUS1 hybrid nanoflower was used for the preparation of GAMG through GL hydrolysis, with the conversion rate of 92% in 8 h, and after eight consecutive runs, it had 60% of its original activity.

关键词： β-glucuronidase     enzyme-inorganic hybrid nanoflower     biotransformation     glycyrrhizin     glycyrrtinic acid 3-O-mono-β-D-glucuronide    

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Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 465-470 doi: 10.1007/s11705-014-1452-8

摘要： The utilization of poly (2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investigated. Grafted copolymers of 2-hydroxyethylmethacrylate (HEMA) monomers on agar were synthesized by microwave assisted method. drug release studies were performed at pH values of 2 and 7 in order to investigate the possibility of pH triggered release for colon targeted drug delivery. Further, the percent grafting . (the time taken for release of 50% of the enclosed drug) value was studied and the results indicate that it may be possible to develop a programmable drug release matrix based on grafted polysaccharide. Ag-g-P(HEMA) appears to be a useful matrix for controlled release.

关键词： agar     controlled drug release     5-Amino salicylic acid     poly(2-hydroxyethylmethacrylate) grafted agar    

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富含sn-2 DHA脂质对大脑的益处及其酶法合成综述 Review

金俊, 金青哲, 王兴国, Casimir C. Akoh

《工程（英文）》 2020年 第6卷 第4期   页码 424-431 doi: 10.1016/j.eng.2020.02.009

摘要： 甘油酯sn-2位上的DHA可以被肠黏膜更好地吸收，从而实现机体对DHA的高效利用。为了全面了解DHA对大脑的有益功能，本文系统介绍了天然油脂甘油骨架上DHA的位置分布（sn-2和sn-1,3位）特征，并讨论了DHA补充和通过肠-脑轴传递信息的潜在功能机制为了在日常饮食中摄入更多的sn-2 DHA，我们建议通过更为高效和经济的酯交换制造技术生产富含sn-2 DHA脂质，其中需要解决的关键技术包括强化酶的特异性和优化纯化工艺这类饮食可满足对sn-2 关键词： DHA 和 sn-2 DHA     单甘酯     大脑     肠-脑轴     结构脂质    

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标题 作者 时间 类型 操作

Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

期刊论文

Effect of exhaust gas recirculation and ethyl hexyl nitrate additive on biodiesel fuelled diesel engine

K. VENKATESWARLU, B. S. R MURTHY, V. V. SUBBARAO, K. Vijaya KUMAR

期刊论文

Supercritical carbon dioxide extraction of CLA-ethyl ester

Yingdi CHEN, Peng XU, Jian CHENG

期刊论文

Synthesis and bulk polymerization kinetics of monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethylester

Haibo ZHANG,Yanping YANG,He LIU,Jie SONG,Shibin SHANG,Zhanqian SONG

期刊论文

Toughening of vinyl ester resins by two-dimensional MXene nanosheets

期刊论文

Catalytic oxidation of carbon monoxide, toluene, and ethyl acetate over the

Zhidan Fu, Lisha Liu, Yong Song, Qing Ye, Shuiyuan Cheng, Tianfang Kang, Hongxing Dai

期刊论文

Energy-efficient recovery of tetrahydrofuran and ethyl acetate by triple-column extractive distillation

Ao Yang, Yang Su, Tao Shi, Jingzheng Ren, Weifeng Shen, Teng Zhou

期刊论文

A comparison of the biological activities of ethyl acetate fractions from the stems and leaves of

Zhaolei WANG, Kai JIANG, Qinchao DING, Shujun LIU, Xiaobing DOU, Bin DING

期刊论文

Unravelling the bottleneck of phosphonic acid anchoring groups aiming toward enhancing the stability

期刊论文

Proline-2′-deoxymugineic acid, a phytosiderophore analog, drives beneficial rhizobacterial community

期刊论文

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

期刊论文

Investigation of the effects of humic acid and H 2 O 2 on the photocatalytic degradation of atrazine

Chao QIN, Shaogui YANG, Cheng SUN, Jia ZHOU, Manjun ZHAN, Rongjun WANG, Huanxing CAI,

期刊论文

PGUS1 hybrid nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid3-O-mono-β-D-glucuronide preparation

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

期刊论文

Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

期刊论文

富含sn-2 DHA脂质对大脑的益处及其酶法合成综述

金俊, 金青哲, 王兴国, Casimir C. Akoh

期刊论文