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Solvent-free mechanochemical mild oxidation method to enhance adsorption properties of chitosan

《环境科学与工程前沿（英文）》 2021年第15卷第6期 doi: 10.1007/s11783-021-1416-4

摘要：

• Solvent-free chitosan oxidation is obtained by rapid mechanochemical reaction.

关键词： Chitosan High energy ball milling Mechanochemistry Oxidation

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Expression and characterization of a CALB-type lipase from

Jiang-Wei Shen, Xue Cai, Bao-Juan Dou, Feng-Yu Qi, Xiao-Jian Zhang, Zhi-Qiang Liu, Yu-Guo Zheng

《化学科学与工程前沿（英文）》 2020年第14卷第5期页码 868-879 doi: 10.1007/s11705-019-1889-x

摘要： A lipase from SRZ2 (SRL) with 73% amino acid sequence identity to lipase B (CALB) was cloned and overexpressed in . The recombinant SRL showed a preference for short-chain -nitrophenyl esters. It achieved maximum activity at pH 8.0 and 65°C for -nitrophenyl hexanoate (C6) with and / values of 0.14 mmol∙L and 1712 min ∙mmol∙L at 30°C, respectively. SRL displayed excellent thermostability and pH stability, retaining more than 79% of its initial activity after incubation at 60°C for 72 h and 75% at pH 3 to 11 for 72 h. It also maintained most of its activity in the presence of inhibitors and detergents except sodium dodecyl sulfate, and it tolerated organic solvents. SRL was covalently immobilized and successfully used for ethyl hexanoate synthesis in cyclohexane or in a solvent-free system with a high conversion yield (>95%). Furthermore, high conversion yield was also achieved for the synthesis of various short-chain flavor esters when high substrate concentrations of 2 mol∙L were applied. This study indicated that a CALB-type lipase from SRZ2 showed great potential in organic ester synthesis.

关键词： lipase Sporisorium reilianum biochemical characterization short-chain flavor ester solvent-free system

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Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selective catalytic oxidation of cyclohexane

《化学科学与工程前沿（英文）》 2022年第16卷第8期页码 1211-1223 doi: 10.1007/s11705-022-2145-3

摘要： The one-step highly selective oxidation of cyclohexane into cyclohexanone and cyclohexanol as the essential intermediates of nylon-6 and nylon-66 is considerably challenging. Therefore, an efficient and low-cost catalyst must be urgently developed to improve the efficiency of this process. In this study, a Co₃O₄–CeO₂ composite oxide catalyst was successfully prepared through ultrasound-assisted co-precipitation. This catalyst exhibited a higher selectivity to KA-oil, which was benefited from the synergistic effects between Co³⁺/Co²⁺ and Ce⁴⁺/Ce³⁺ redox pairs, than bulk CeO₂ and/or Co₃O₄. Under the optimum reaction conditions, 89.6% selectivity to KA-oil with a cyclohexane conversion of 5.8% was achieved over Co₃O₄–CeO₂. Its catalytic performance remained unchanged after five runs. Using the synergistic effects between the redox pairs of different transition metals, this study provides a feasible strategy to design high-performance catalysts for the selective oxidation of alkanes.

关键词： Co₃O₄–CeO₂ composite oxides cyclohexanone cyclohexanol ultrasonic-assisted co-precipitation selective oxidation solvent-free

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实现“不可行”的共聚反应以构筑氮掺杂多孔碳的理想聚合物前驱体 Article

亓士超, 陆筱杰, 楼寅聪, 周睿, 薛丁铭, 刘晓勤, 孙林兵

《工程（英文）》 2022年第16卷第9期页码 154-161 doi: 10.1016/j.eng.2021.07.031

摘要：

某些预想的概念验证反应虽可能产生具有新功能或新应用潜力的材料，但最终常被证明是不可实现的或从商业角度上是不可行的。为了在溶剂环境中探索未知反应的反应条件，科研人员已付出了大量的努力，也浪费了大量的精力。因为人们普遍相信通过将反应物溶解在溶剂中，可以提高反应物的活性，从而促进反应。本研究发现了一个反常现象：在不同溶剂环境下，1,3,5-三（氯甲基）-2,4,6-三甲基苯与三聚氰胺的共聚反应都是无法实现的，然而利用无溶剂法却可成功地实现该反应。通过第一性原理计算和分子动力学模拟，证明了溶剂反应不具备的两个决定性因素，即由副产物的及时释放所推动的反应平衡和活化单体分子在固相中的受限热运动却可基于无溶剂法实现。由于具有较高的芳香性和氮杂环含量，由无溶剂法得到的共聚物表现出良好的应用潜力，可作为制备氮掺杂多孔碳的前驱体，使氮掺杂多孔碳具有令人满意的碳产率、理想的残氮含量、理想的结构特性，与最近报道的其他代表性同类吸附剂相比，在二氧化碳捕获能力方面展现出竞争潜力。

关键词：无溶剂法溶剂效应共聚反应氮掺杂多孔碳

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Study of an artificial boundary condition based on the damping-solvent extraction method

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

《结构与土木工程前沿（英文）》 2012年第6卷第3期页码 281-287 doi: 10.1007/s11709-012-0167-5

摘要： A new artificial boundary condition for time domain analysis of a structure-unlimited-foundation system was proposed. The boundary condition was based on the damping-solvent extraction method. The principle of the damping-solvent extraction method was described. An artificial boundary condition was then established by setting two spring-damper systems and one artificial damping limited region. A test example was developed to verify that the proposed boundary condition and model had high precision. Compared with the damping-solvent extraction method, this boundary condition is easier to be applied to finite element method (FEM)-based numerical calculations.

关键词： damping-solvent extraction method structure-unlimited-foundation system spring-damper system artificial damping limited region finite element method

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Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

《化学科学与工程前沿（英文）》 2017年第11卷第1期页码 58-65 doi: 10.1007/s11705-017-1610-x

摘要： The advent of synthetic biology has ushered in new applications of cell-free transcription-translation systems. These cell-free systems are reconstituted using cellular proteins, and are amenable to modular control of their composition. Here, we discuss the historical advancement of cell-free systems, as well as their new applications in the rapid design of synthetic genetic circuits and components, directed evolution of biomolecules, diagnosis of infectious diseases, and synthesis of vaccines. Finally, we present our vision on the future direction of cell-free synthetic biology.

关键词： cell-free system application

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Preliminary study on preparation of cell-free system for protein expression

CHEN Haiqin, XU Zhinan, WANG Cheng, CEN Peilin, LIAO Yuhua

《化学科学与工程前沿（英文）》 2008年第2卷第2期页码 224-229 doi: 10.1007/s11705-008-0029-9

摘要： In the new era of “Omics”, the traditional techniques of protein expression in vivo can not come up with the exponential increase of genetic information. The cell-free protein synthesis system provides a new strategy of protein expression with advantages of rapid, convenient and high-throughput expression. The preparation of cell extracts, the optimization of substrate concentrations and the energy regeneration system are the key factors for the successful construction of cell-free protein expression system. In this work, the cell extract was prepared from RNase I- defective strain A19. The cell growth phase, the pressure for cell disruption and the storage condition of cell extracts were optimized. Meanwhile, the optimal substrate concentrations and the energy regeneration system were selected. Under the optimized conditions, the green fluorescent protein (GFP) reporter gene was expressed in the cell-free system with high expression level (Ca. 154 ?g/mL) which was 29 times higher than the expression level before optimization.

关键词： cell-free regeneration extract information successful construction

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A space power system of free piston Stirling generator based on potassium heat pipe

Mingqiang LIN, Jian MOU, Chunyun CHI, Guotong HONG, Panhe GE, Gu HU

《能源前沿（英文）》 2020年第14卷第1期页码 1-10 doi: 10.1007/s11708-019-0655-6

摘要： The power system of a free piston Stirling generator (FPSG) based on potassium heat pipes has been developed in this paper. Thanks to the advantages of long life, high reliability, and high overall thermal efficiency, the FPSG is a promising candidate for nuclear energy, especially in space exploration. In this paper, the recent progress of FPSG based on nuclear reactor for space use was briefly reviewed. A novel FPSG weighted only 4.2 kg was designed, and one dimensional thermodynamic modeling of the FPSG using Sage software was performed to estimate its performance. The experiment results indicated that this FPSG could provide 142.4 W at a thermal-to-electric efficiency of nearly 17.4%. Besides, the power system integrated with four FPSGs and potassium heat pipes was performed and the single machine failure test was conducted. The results show that this system could provide an electrical power of 300 W at an overall thermal efficiency of 7.3%. Thus, it is concluded that this power system is feasible and will have a great prospect for future applications.

关键词： free piston Stirling generator (FPSG) potassium heat pipe power system energy conversion

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Design and modeling of a free-piston engine generator

《能源前沿（英文）》页码 811-821 doi: 10.1007/s11708-022-0848-2

摘要： Free-piston engine generators (FPEGs) can be applied as decarbonized range extenders for electric vehicles because of their high thermal efficiency, low friction loss, and ultimate fuel flexibility. In this paper, a parameter-decoupling approach is proposed to model the design of an FPEG. The parameter-decoupling approach first divides the FPEG into three parts: a two-stroke engine, an integrated scavenging pump, and a linear permanent magnet synchronous machine (LPMSM). Then, each of these is designed according to predefined specifications and performance targets. Using this decoupling approach, a numerical model of the FPEG, including the three aforementioned parts, was developed. Empirical equations were adopted to design the engine and scavenging pump, while special considerations were applied for the LPMSM. A finite element model with a multi-objective genetic algorithm was adopted for its design. The finite element model results were fed back to the numerical model to update the LPMSM with increased fidelity. The designed FPEG produced 10.2 kW of electric power with an overall system efficiency of 38.5% in a stable manner. The model provides a solid foundation for the manufacturing of related FPEG prototypes.

关键词： free-piston engine generator linear permanent magnet synchronous machine system design numerical model finite element method

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Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

《化学科学与工程前沿（英文）》 2022年第16卷第12期页码 1689-1699 doi: 10.1007/s11705-022-2186-7

摘要： Radicals are important intermediates in direct coal liquefaction. Certain radicals can cause the cleavage of chemical bonds. At high temperatures, radical fragments can be produced by the splitting of large organic molecules, which can break strong chemical bonds through the induction pyrolysis of radicals. The reaction between the formation and annihilation of coal radical fragments and the effect of hydrogen-donor solvents on the radical fragments are discussed in lignite hydrogenolysis. Using the hydroxyl and ether bonds as indicators, the effects of different radicals on the cleavage of chemical bond were investigated employing density functional theory calculations and lignite hydrogenolysis experiments. Results showed that the adjustment of the coal radical fragments could be made by the addition of hydrogen-donor solvents. Results showed that the transition from coal radical fragment to H radical leads to the variation of product distribution. The synergistic mechanism of hydrogen supply and hydrogenolysis of hydrogen-donor solvent was proposed.

关键词： direct coal liquefaction hydrogen-donor solvent induced pyrolysis radical mechanism density functional theory calculations

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Micronization of curcumin with biodegradable polymer by supercritical anti-solvent using micro swirl

Kimthet Chhouk, Wahyudiono, Hideki Kanda, Shin-Ichro Kawasaki, Motonobu Goto

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 184-193 doi: 10.1007/s11705-017-1678-3

摘要： Curcumin is a hydrophobic polyphenol compound exhibiting a wide range of biological activities such as anti-inflammatory, anti-bacterial, anti-fungal, anti-carcinogenic, anti-human immunodeficiency virus, and anti-microbial activity. In this work, a swirl mixer was employed to produce the micronized curcumin with polyvinylpyrrolidone (PVP) by the supercritical anti-solvent process to improve the bioavailability of curcumin. The effects of operating parameters such as curcumin/PVP ratio, feed concentration, temperature, pressure, and CO flow rate were investigated. The characterization and solubility of particles were determined by using scanning electron microscopy, Fourier Transform Infrared spectroscopy, and ultra-violet-visible spectroscopy. The result shows that the optimal condition for the production of curcumin/PVP particles is at curcumin/PVP ratio of 1:30, feed concentration of 5 mg·mL , temperature of 40 °C, pressure of 15 MPa, and CO flow rate of 15 mL·min . Moreover, the dissolution of curcumin/PVP particles is faster than that of raw curcumin.

关键词： micronization curcumin polyvinylpyrrolidone supercritical anti-solvent swirl mixer

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Deep eutectic solvent inclusions for high- composite dielectric elastomers

《化学科学与工程前沿（英文）》 2022年第16卷第6期页码 996-1002 doi: 10.1007/s11705-022-2138-2

摘要： Recent advances in novel electroactive devices have placed new requirements on material development. High-performance dielectric elastomers with good mechanical stretchability and high dielectric constant are under high demand. However, the current strategy for fabricating these materials suffers from high cost or low thermal stability, which greatly hinders large-scale industrial production. Herein, we have successfully developed a novel strategy for improving the dielectric constant of polymeric elastomers via deep eutectic solvent inclusion by taking advantage of the low cost, convenient and environmentally benign synthesis process and high ionic conductivity from deep eutectic solvents. The as-prepared composite elastomers showed good stretchability and a greatly enhanced dielectric constant with a negligible increase in dielectric dissipation. Moreover, we have proven the universality of our strategy by using different types of deep eutectic solvents. It is believed that low-cost, easy-synthesis and environmentally friendly deep eutectic solvents including composite elastomers are highly suitable for large-scale industrial production and can greatly broaden the application fields of dielectric elastomers.

关键词： composite materials deep eutectic solvent dielectric elastomer high dielectric constant

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A new procedure combining GC-MS with accelerated solvent extraction for the analysis of phthalic acid

Tingting MA, Ying TENG, Peter CHRISTIE, Yongming LUO, Yongshan CHEN, Mao YE, Yujuan HUANG

《环境科学与工程前沿（英文）》 2013年第7卷第1期页码 31-42 doi: 10.1007/s11783-012-0463-2

摘要： An optimized procedure based on gas chromatography-mass spectrometry (GC-MS) combined with accelerated solvent extraction (ASE) is developed for the analysis of six phthalic acid esters (PAEs), which are priority soil pollutants nominated by United States Environmental Protection Agency (USEPA). Quantification of PAEs in soil employs ultrasonic extraction (UE) (USEPA 3550) and ASE (USEPA 3545), followed by clean up procedures involving three different chromatography columns and two combined elution methods. GC-MS conditions under selected ion monitoring (SIM) mode are described and quality assurance and quality control (QA/QC) criteria with high accuracy and sensitivity for target analytes were achieved. Method reliability is assured with the use of an isotopically labeled PAE, di- -butyl phthalate-d4 (DnBP-D4), as a surrogate, and benzyl benzoate (BB) as an internal standard, and with the analysis of certified reference materials (CRM). QA/QC for the developed procedure was tested in four PAE-spiked soils and one PAE-contaminated soil. The four spiked soils were originated from typical Chinese agricultural fields and the contaminated soil was obtained from an electronic waste dismantling area. Instrument detection limits (IDLs) for the six PAEs ranged 0.10–0.31 μg·L and method detection limits (MDLs) of the four spiked soils varied from a range of 20–70 μg·kg to a range of 90– 290 μg·kg . Linearity of response between 20 μg·L and 2 mg·L was also established and the correlation coefficients ( ) were all>0.998. Spiked soil matrix showed relative recovery rates between 75 and 120% for the six target compounds and about 93% for the surrogate substance. The developed procedure is anticipated to be highly applicable for field surveys of soil PAE pollution in China.

关键词： phthalic acid esters quality assurance and quality control soil type accelerated solvent extraction certified reference materials

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Purification of artemisinin from quercetin by anti-solvent crystallization

Chandrakant R. MALWADE, Haiyan QU, Ben-Guang RONG, Lars P. CHRISTENSEN

《化学科学与工程前沿（英文）》 2013年第7卷第1期页码 72-78 doi: 10.1007/s11705-013-1305-x

摘要： In the present work, anti-solvent crystallization of artemisinin from four different organic solvents (methanol, ethanol, acetonitrile, and acetone) was studied. Water was used as anti-solvent. The effect of an impurity (quercetin) on the performance of anti-solvent crystallization of artemisinin was investigated. The fundamental process data such as solubility of artemisinin in pure organic solvents and their binary mixtures with varying composition water were measured at room temperature. The solubility of quercetin was measured only in pure organic solvents at room temperature. Anti-solvent crystallization experiments were designed based on the fundamental process data determined. Firstly, the anti-solvent crystallization of artemisinin without impurity was performed from all four organic solvents and then the experiments were repeated with addition of an impurity (quercetin) while keeping all other process parameters constant. Two different concentrations of impurity, i.e., 10% and 50% of its solubility, in the respective organic solvents at room temperature were used. The effect of impurity on performance of anti-solvent crystallization was evaluated by comparing the yield and purity of the artemisinin obtained with those in the absence of impurity. Results of the present work demonstrated that the presence of quercetin in the solution does not affect the final yield of artemisinin from the solution of each of four organic solvents used. However, the purity of artemisinin crystals were reduced when quercetin concentration was 50% of its solubility in all solvents studied.

关键词： anti-solvent crystallization artemisinin quercetin solubility Artemisia annua

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Review of solvent based carbon-dioxide capture technologies

Kathryn A. MUMFORD,Yue WU,Kathryn H. SMITH,Geoffrey W. STEVENS

《化学科学与工程前沿（英文）》 2015年第9卷第2期页码 125-141 doi: 10.1007/s11705-015-1514-6

摘要： Currently, a large proportion of global fossil fuel emissions originate from large point sources such as power generation or industrial processes. This trend is expected to continue until the year 2030 and beyond. Carbon capture and storage (CCS), a straightforward and effective carbon reduction approach, will play a significant role in reducing emissions from these sources into the future if atmospheric carbon dioxide (CO ) emissions are to be stabilized and global warming limited below a threshold of 2 °C. This review provides an update on the status of large scale integrated CCS technologies using solvent absorption for CO capture and provides an insight into the development of new solvents, including advanced amine solvents, amino acid salts, carbonate systems, aqueous ammonia, immiscible liquids and ionic liquids. These proposed new solvents aim to reduce the overall cost CO capture by improving the CO absorption rate, CO capture capacity, thereby reducing equipment size and decreasing the energy required for solvent regeneration.

关键词： large scale carbon dioxide carbon capture solvent absorption