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Electricity-driven ammonia oxidation and acetate production in microbial electrosynthesis systems

《环境科学与工程前沿（英文）》 2022年 第16卷 第4期 doi: 10.1007/s11783-021-1476-5

摘要：

• MES was constructed for simultaneous ammonia removal and acetate production.

关键词： Biocathode     Carbon dioxide     Electrochemical oxidation     Graphite anode     Boron-doped diamond    

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Durable and recyclable BiOBr/silk fibroin-cellulose acetate composite film for efficient photodegradation

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1765-1775 doi: 10.1007/s11705-023-2323-y

摘要： A stable and recyclable of BiOBr/silk fibroin-cellulose acetate composite film was prepared by blending-wet phase transformation and in situ precipitate technology. The cellulose acetate film modified by silk fibroin formed a finger-shaped porous structure, which provided a large space for the uniform growth of BiOBr nanosheets and facilitated the shuttle flow of dyes in film. The morphology, phase structure, and optical properties of the composite films were characterized using various techniques, and their photocatalytic performance for dye wastewater was evaluated under visible light irradiation. Results showed that the BiOBr/SF-CA composite film exhibited efficient photocatalytic activity with 99.9% of rhodamine B degradation rate. Moreover, the composite film maintained high catalytic stability because Bi as the active species deposited on the film showed almost no loss. Finally, the possible photocatalytic mechanisms in the BiOBr/SF-CA composite film were speculated through radical-trapping experiments and electron spin resonance testing.

关键词： BiOBr nanosheet     cellulose acetate     silk fibroin     photocatalytic degradation     dye wastewater    

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Methyl acetate–methanol mixture separation by extractive distillation: Economic aspects

Elena Graczová, Branislav Šulgan, Samuel Barabas, Pavol Steltenpohl

《化学科学与工程前沿（英文）》 2018年 第12卷 第4期   页码 670-682 doi: 10.1007/s11705-018-1769-9

摘要：

Methyl acetate is considered low toxicity volatile solvent produced either as a by-product during methanol carbonylation or via acetic acid esterification with methanol. In both cases, pure methyl acetate has to be isolated from the reaction mixture. Simulation of methyl acetate separation from its mixture with methanol by extraction distillation was carried out in ASPEN+ software. In total three case studies were assumed using two different extraction solvents and two solvent regeneration strategies. In case A, novel extraction solvent 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid, was considered. Raw material separation was achieved in an extraction distillation column while the solvent regeneration was accomplished in a second distillation column in this case. In case study B, the same extraction solvent was used; however, its regeneration was carried out in a single-effect evaporator. Dimethyl sulfoxide was the second extraction solvent selected. Its use in methyl acetate-methanol separation is presented in case study C. As high purity of dimethyl sulfoxide was required for the methyl acetate-methanol azeotrope breaking, its regeneration was carried out in the second distillation column only. To simulate the ternary methyl acetate–methanol–extraction solvent mixtures separation, vapor–liquid equilibrium was predicted based on the NRTL equation. Further, unknown properties of the considered ionic liquid and variation of these properties with temperature were predicted and introduced into the ASPEN+ components properties database. Based on these data, optimum operation parameters of the respective separation equipment were established. In all case studies, the same condition had to be fulfilled, namely minimum methyl acetate content in the distillate from the extraction distillation column of 99.5mol-%. Results of simulations using the respective optimum operation parameters were employed in the economic evaluation of the three separation unit designs studied. It was found that the least energy-demanding design corresponds to the case study B in terms of both capital as well as operation expenses.

关键词： methyl acetate     1-ethyl-3-methylimidazolium trifluoromethanesulfonate     extraction distillation     dimethyl sulfoxide     economic evaluation    

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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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The rpoS deficiency suppresses acetate accumulation in glucose-enriched culture of <

Prayoga SURYADARMA, Yoshihiro OJIMA, Yuto FUKUDA, Naohiro AKAMATSU, Masahito TAYA

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 152-157 doi: 10.1007/s11705-012-1287-0

摘要： The role of on the central carbon metabolism was investigated through analyzing the deficiency of this regulon gene under aerobic and glucose-enriched culture conditions. The experimental results showed that while the wild type cells exhibited an overflow metabolism effect, the -deleting mutation alleviated this effect with the significant suppression of acetate accumulation under a high glucose condition. This gene deletion also induced the twofold upregulation of and one-tenth downregulation of , respectively. The overflow metabolism effect was confirmed to be recovered by re-introducing gene into the mutant. These results demonstrated changed the central carbon metabolism toward acetate overflow through dehydrogenation of pyruvate and reduction of TCA cycle activity.

关键词： Escherichia coli     rpoS     aerobic and glucose-enriched culture     overflow metabolism    

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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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Influence of accelerated curing on the compressive strength of polymer-modified concrete

Izhar AHMAD; Kashif Ali KHAN; Tahir AHMAD; Muhammad ALAM; Muhammad Tariq BASHIR

《结构与土木工程前沿（英文）》 2022年 第16卷 第5期   页码 589-599 doi: 10.1007/s11709-022-0789-1

摘要： In recent building practice, rapid construction is one of the principal requisites. Furthermore, in designing concrete structures, compressive strength is the most significant of all parameters. While 3-d and 7-d compressive strength reflects the strengths at early phases, the ultimate strength is paramount. An effort has been made in this study to develop mathematical models for predicting compressive strength of concrete incorporating ethylene vinyl acetate (EVA) at the later phases. Kolmogorov-Smirnov (KS) goodness-of-fit test was used to examine distribution of the data. The compressive strength of EVA-modified concrete was studied by incorporating various concentrations of EVA as an admixture and by testing at ages of 28, 56, 90, 120, 210, and 365 d. An accelerated compressive strength at 3.5 hours was considered as a reference strength on the basis of which all the specified strengths were predicted by means of linear regression fit. Based on the results of KS goodness-of-fit test, it was concluded that KS test statistics value (D) in each case was lower than the critical value 0.521 for a significance level of 0.05, which demonstrated that the data was normally distributed. Based on the results of compressive strength test, it was concluded that the strength of EVA-modified specimens increased at all ages and the optimum dosage of EVA was achieved at 16% concentration. Furthermore, it was concluded that predicted compressive strength values lies within a 6% difference from the actual strength values for all the mixes, which indicates the practicability of the regression equations. This research work may help in understanding the role of EVA as a viable material in polymer-based cement composites.

关键词： compressive strength prediction     polymer-modified concrete     linear regression fit     early age strength     ethylene vinyl acetate    

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Benzenesulfonic acid-grafted UIO-66 with improved hydrophobicity as a stable Brønsted acid catalyst

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1389-1398 doi: 10.1007/s11705-022-2285-5

摘要： Hydrothermal and catalytic stability of UIO-66 MOFs with defective structures are critical aspects to be considered in their catalytic applications, especially under the conditions involving water, moisture and/or heat. Here, we report a facile strategy to introduce the macromolecular acid group to UIO-66 to improve the stability of the resulting UIO-66−PhSO3H MOF in aqueous phase catalysis. In detail, UIO-66−PhSO3H was obtained by grafting benzenesulfonic acid on the surface of the pristine UIO-66 to introduce the hydrophobicity, as well as the Brønsted acidity, then assessed using catalytic hydrolysis of cyclohexyl acetate (to cyclohexanol) in water. The introduction of hydrophobic molecules to UIO-66 could prevent the material from being attacked by hydroxyl polar molecules effectively, explaining its good structural stability during catalysis. UIO-66−PhSO3H promoted the conversion of cyclohexyl acetate at ca. 87%, and its activity and textural properties were basically intact after the cyclic stability tests. The facile modification strategy can improve the hydrothermal stability of UIO-66 significantly, which can expand its catalytic applications in aqueous systems.

关键词： metal−organic frameworks (MOFs)     UIO-66     hydrolysis of cyclohexyl acetate     hydrophobicity     Brønsted acidity    

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Halide-free carbonylation of methanol with H-MOR supported CuCeO

Chaoli Tong, Jiachang Zuo, Danlu Wen, Weikun Chen, Linmin Ye, Youzhu Yuan

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1075-1087 doi: 10.1007/s11705-020-2019-5

摘要： Heterogeneous halide-free carbonylation of methanol to acetates, including methyl acetate (MA) and acetic acid, using non-precious metal catalysts has been a topic of interest for decades. The key issue is that the water produced by methanol dehydration inhibits the formation of acetyl species and reduces the MA selectivity. Here, we report that CuCeO /H-mordenite (H-MOR) catalyst can nearly eliminate the inhibiting effect of water on carbonylation by a water-gas shift reaction (WGSR) on-site, and can thus achieve 96.5% methanol conversion with 87.4% MA selectivity for the halide-free carbonylation of methanol. The results of powder X-ray diffraction, transmission electron microscopy, and scanning electron microscopy show that the Cu and Ce species are highly dispersed on H-MOR even when the CuCeO contents are as high as 29 wt-%. Fourier transform infrared spectroscopy and CO chemisorption analysis reveal that a small portion of Cu species can migrate into the channel of H-MOR when CuCeO /H-MOR is calcined at 500 °C and these Cu species are converted into Cu sites upon reduction. The Cu sites facilitate the WGSR and are also active sites for methanol carbonylation. The introduction of Ce benefits the inhibition of coke deposits and thus enhances the catalyst stability.

关键词： methanol carbonylation     halide-free     methyl acetate     H-mordenite     copper and cerium oxide    

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Microbial communities biostimulated by ethanol during uranium (VI) bioremediation in contaminated sediment as shown by stable isotope probing

Mary Beth LEIGH,Wei-Min WU,Erick CARDENAS,Ondrej UHLIK,Sue CARROLL,Terry GENTRY,Terence L. MARSH,Jizhong ZHOU,Philip JARDINE,Craig S. CRIDDLE,James M. TIEDJE

《环境科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 453-464 doi: 10.1007/s11783-014-0721-6

摘要： Stable isotope probing (SIP) was used to identify microbes stimulated by ethanol addition in microcosms containing two sediments collected from the bioremediation test zone at the US Department of Energy Oak Ridge site, TN, USA. One sample was highly bioreduced with ethanol while another was less reduced. Microcosms with the respective sediments were amended with C labeled ethanol and incubated for 7 days for SIP. Ethanol was rapidly converted to acetate within 24 h accompanied with the reduction of nitrate and sulfate. The accumulation of acetate persisted beyond the 7 d period. Aqueous U did not decline in the microcosm with the reduced sediment due to desorption of U but continuously declined in the less reduced sample. Microbial growth and concomitant C-DNA production was detected when ethanol was exhausted and abundant acetate had accumulated in both microcosms. This coincided with U(VI) reduction in the less reduced sample. C originating from ethanol was ultimately utilized for growth, either directly or indirectly, by the dominant microbial community members within 7 days of incubation. The microbial community was comprised predominantly of known denitrifiers, sulfate-reducing bacteria and iron (III) reducing bacteria including , , , and others, including the known U(VI)-reducing bacteria A , and The findings suggest that ethanol biostimulates the U(VI)-reducing microbial community by first serving as an electron donor for nitrate, sulfate, iron (III) and U(VI) reduction, and acetate which then functions as electron donor for U(VI) reduction and carbon source for microbial growth.

关键词： Stable isotope probing (SIP)     ethanol     acetate     uranium reduction     sediment     bioremediation    

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标题 作者 时间 类型 操作

Electricity-driven ammonia oxidation and acetate production in microbial electrosynthesis systems

期刊论文

Durable and recyclable BiOBr/silk fibroin-cellulose acetate composite film for efficient photodegradation

期刊论文

Methyl acetate–methanol mixture separation by extractive distillation: Economic aspects

Elena Graczová, Branislav Šulgan, Samuel Barabas, Pavol Steltenpohl

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

The rpoS deficiency suppresses acetate accumulation in glucose-enriched culture of <

Prayoga SURYADARMA, Yoshihiro OJIMA, Yuto FUKUDA, Naohiro AKAMATSU, Masahito TAYA

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

Influence of accelerated curing on the compressive strength of polymer-modified concrete

Izhar AHMAD; Kashif Ali KHAN; Tahir AHMAD; Muhammad ALAM; Muhammad Tariq BASHIR

期刊论文

Benzenesulfonic acid-grafted UIO-66 with improved hydrophobicity as a stable Brønsted acid catalyst

期刊论文

Halide-free carbonylation of methanol with H-MOR supported CuCeO

Chaoli Tong, Jiachang Zuo, Danlu Wen, Weikun Chen, Linmin Ye, Youzhu Yuan

期刊论文

Microbial communities biostimulated by ethanol during uranium (VI) bioremediation in contaminated sediment as shown by stable isotope probing

Mary Beth LEIGH,Wei-Min WU,Erick CARDENAS,Ondrej UHLIK,Sue CARROLL,Terry GENTRY,Terence L. MARSH,Jizhong ZHOU,Philip JARDINE,Craig S. CRIDDLE,James M. TIEDJE

期刊论文