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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    

Extraction of hydrogen chloride by a coupled reaction-solvent extraction process

Yunzhao Li,Xingfu Song,Guilan Chen,Shuying Sun,Yanxia Xu,Jianguo Yu

《化学科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 479-487 doi: 10.1007/s11705-015-1512-8

摘要: A coupled reaction-solvent extraction process was used to remove HCl from a simulated distiller waste. The extraction performances of various extractants and diluents were compared and the apparent basicity of N235 (a mixture of tertiary amines) in various diluents was determined. The best results were obtained using N235 and isoamyl alcohol as the extractant and diluent, respectively. The yield of HCl from the coupled extraction was 75% with this extraction system. The mechanisms for the removal of HCl in both the direct and coupled extractions were investigated. For the coupled extraction, the formation of an R NHCl ion-pair complex was involved in the HCl removal. For the direct extraction, the mechanism involved the formation of hydrogen bonds at high concentrations of HCl.

关键词: hydrogen chloride     distiller waste     coupled reaction and solvent extraction     N235     extraction mechanism    

Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

《化学科学与工程前沿(英文)》 2023年 第17卷 第1期   页码 56-67 doi: 10.1007/s11705-022-2185-8

摘要: Separation of vanadium from black shale leaching solution at low pH is very meaningful, which can effectively avoid the generation of alkali neutralization slag and the resulting vanadium loss. In this study, coordination mechanism of vanadium in acid leaching solution at low pH was investigated with the intervention of chloride ions. Under the conditions of pH 0.8, di-(2-ethylhexyl)phosphoric acid concentration of 20%, phase ratio of 1:2, and extraction time of 8 min, the vanadium extraction could reach 80.00%. The Fourier transform infrared and electrospray ionization results reveal that, despite the fact that the chloride ion in the leachate could significantly promote vanadium extraction, the chloride ion does not enter the organic phase, indicating an intriguing phenomenon. Among Cl–V, SO42−–V, and H2O–V, the V–Cl bond is longer and the potential difference between coordinate ions and vanadium is smaller. Therefore, VO2+ gets easily desorbed with chloride ions and enter the organic phase. At the same time, the hydrogen ions of di-(2-ethylhexyl)phosphoric acid also enter the water phase more easily, which reduces the pH required for the extraction reaction.

关键词: vanadium     black shale     solvent extraction     high acidity extraction    

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    

Coextraction of vanadium and manganese from high-manganese containing vanadium wastewater by a solventextraction-precipitation process

Zishuai Liu, Yimin Zhang, Zilin Dai, Jing Huang, Cong Liu

《化学科学与工程前沿(英文)》 2020年 第14卷 第5期   页码 902-912 doi: 10.1007/s11705-019-1887-z

摘要: High-manganese containing vanadium wastewater (HMVW) is commonly produced during the vanadium extraction process from vanadium titano-magnetite. HMVW cannot be reused and discharged directly, and is harmful to the environment and affect product quality due to heavy metals in the wastewater. The wastewater is usually treated by lime neutralization, but valuable metals (especially V and Mn) cannot be recovered. In this study, an efficient and environmentally friendly method was developed to recover valuable metals by using a solvent extraction-precipitation process. In the solvent extraction process, 98.15% of vanadium was recovered, and the V O product, with a purity of 98.60%, was obtained under optimal conditions. For the precipitation process, 91.05% of manganese was recovered as MnCO which meets the III grade standard of HG/T 2836-2011. Thermodynamic simulation analysis indicated that MnCO was selectively precipitated at pH 6.5 while Mg and Ca could hardly be precipitated. The results of X-ray diffraction and scanning electron microscopy demonstrated that the obtained V O and MnCO displayed a good degree of crystallinity. The treated wastewater can be returned for leaching, and resources (V and Mn) in the wastewater were utilized efficiently in an environmentally friendly way. Therefore, this study provides a novel method for the coextraction of V and Mn from HMVW.

关键词: high-manganese containing vanadium wastewater     solvent extraction     carbonate precipitation     vanadium titano-magnetite     valuable metal recovery    

Selective removal of iron(III) from highly salted chloride acidic solutions by solvent extraction using

Guoping Hu, Yue Wu, Desheng Chen, Yong Wang, Tao Qi, Lina Wang

《化学科学与工程前沿(英文)》 2021年 第15卷 第3期   页码 528-537 doi: 10.1007/s11705-020-1955-4

摘要: Metal ions including Fe , Ca , Mg , Ni , Co and Cu are commonly found in the leaching solution of laterite-nickel ores, and the pre-removal of Fe is extremely important for the recovery of nickel and cobalt. Di(2-ethylhexyl)phosphate acid (D2EHPA) showed high extraction rate and selectivity of Fe over other metal ions. The acidity of the aqueous solution is crucial to the extraction of Fe , and the stoichiometry ratio between Fe and the extractant is 0.86:1.54. The enthalpy for the extraction of Fe using D2EHPA was 19.50 kJ/mol. The extraction of Fe was ≥99% under the optimized conditions after a three-stage solvent extraction process. The iron stripping effects of different reagents showed an order of H C O >NH HCO >HCl>NaCl>NaHCO >Na SO . The stripping of Fe was ≥99% under the optimized conditions using H C O as a stripping reagent.

关键词: solvent extraction     iron     di(2-ethylhexyl)phosphate acid     separation    

Technologies for extracting lipids from oleaginous microorganisms for biodiesel production

Cunwen WANG, Lu CHEN, Bajpai RAKESH, Yuanhang QIN, Renliang LV

《能源前沿(英文)》 2012年 第6卷 第3期   页码 266-274 doi: 10.1007/s11708-012-0193-y

摘要: Recently, biodiesel has received much more attention. Soybean oil, rapeseed oil, palm oil and corn oil are primary feedstock for biodiesel production. However, biodiesel production from these traditional oil-rich crops is limited by land availability, climate, and environmental and social issues regarding the use of feed and food crops for fuel. Oleaginous microorganisms, including microalgae, bacteria, yeast and fungi can be cultivated with high lipid contents and used as promising feedstock for biodiesel production. However, the high cost of biodiesel production using oil microorganisms has been the biggest obstacle for its industrialization. The process of biodiesel production from microorganisms involves many steps, of which the lipids extraction is the most important and costly. Therefore, searching for an effective and economical extraction system is critical. Various approaches of lipids extraction are discussed in this review, including traditional extraction procedures such as solvent extraction, pressing and solvent integrated extraction, as well as some new procedures.

关键词: oleaginous microorganisms     biodiesel     solvent extraction     ultrasound-assisted extraction     microwave-assisted extraction     supercritical fluid extraction (SFE)    

Environmental and economic assessment of vegetable oil production using membrane separation and vapor recompression

Weibin Kong, Qi Miao, Peiyong Qin, Jan Baeyens, Tianwei Tan

《化学科学与工程前沿(英文)》 2017年 第11卷 第2期   页码 166-176 doi: 10.1007/s11705-017-1616-4

摘要: Solvent extraction of crude oil from oilseeds is widely applied for its high production capacity and low cost. In this process, solvent recovery and tail gas treatment are usually performed by adsorption, paraffin scrubbing, or even cryogenics (at low tail gas flow rates). Membrane separation, which has a lower energy consumption than these techniques, spans a broad range of admissible concentrations and flow rates, and is moreover easily combined with other techniques. Vapor recompression has potentials to reduce the heat loss in association with distillation and evaporation. In this study, we proved the possibility of combining membrane separation and vapor recompression to improve the conventional vegetable oil production, by both experiments and process simulation. Nearly 73% of energy can be saved in the process of vegetable oil extraction by the novel processing approach. By further environmental assessment, several impact categories show that the optimized process is environmentally sustainable.

关键词: vegetable oil     solvent-extraction     membrane separation     vapor recompression     environmental and economic assessment    

离子液体在金属离子萃取中的研究进展

刘利梅,苏永庆,李琮,贺飞,何永福,钟云

《中国工程科学》 2007年 第9卷 第11期   页码 187-190

摘要:

介绍了离子液体的定义,发展历史,性质等,重点阐述用于金属离子萃取的离子液体的性质、合成方 法和发展方向。

关键词: 离子液体     萃取     金属离子     绿色溶剂    

Entity and relation extraction with rule-guided dictionary as domain knowledge

《工程管理前沿(英文)》   页码 610-622 doi: 10.1007/s42524-022-0226-0

摘要: Entity and relation extraction is an indispensable part of domain knowledge graph construction, which can serve relevant knowledge needs in a specific domain, such as providing support for product research, sales, risk control, and domain hotspot analysis. The existing entity and relation extraction methods that depend on pretrained models have shown promising performance on open datasets. However, the performance of these methods degrades when they face domain-specific datasets. Entity extraction models treat characters as basic semantic units while ignoring known character dependency in specific domains. Relation extraction is based on the hypothesis that the relations hidden in sentences are unified, thereby neglecting that relations may be diverse in different entity tuples. To address the problems above, this paper first introduced prior knowledge composed of domain dictionaries to enhance characters’ dependence. Second, domain rules were built to eliminate noise in entity relations and promote potential entity relation extraction. Finally, experiments were designed to verify the effectiveness of our proposed methods. Experimental results on two domains, including laser industry and unmanned ship, showed the superiority of our methods. The F1 value on laser industry entity, unmanned ship entity, laser industry relation, and unmanned ship relation datasets is improved by +1%, +6%, +2%, and +1%, respectively. In addition, the extraction accuracy of entity relation triplet reaches 83% and 76% on laser industry entity pair and unmanned ship entity pair datasets, respectively.

关键词: entity extraction     relation extraction     prior knowledge     domain rule    

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    

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    

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    

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    

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    

标题 作者 时间 类型 操作

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

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

期刊论文

Extraction of hydrogen chloride by a coupled reaction-solvent extraction process

Yunzhao Li,Xingfu Song,Guilan Chen,Shuying Sun,Yanxia Xu,Jianguo Yu

期刊论文

Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

期刊论文

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

期刊论文

Coextraction of vanadium and manganese from high-manganese containing vanadium wastewater by a solventextraction-precipitation process

Zishuai Liu, Yimin Zhang, Zilin Dai, Jing Huang, Cong Liu

期刊论文

Selective removal of iron(III) from highly salted chloride acidic solutions by solvent extraction using

Guoping Hu, Yue Wu, Desheng Chen, Yong Wang, Tao Qi, Lina Wang

期刊论文

Technologies for extracting lipids from oleaginous microorganisms for biodiesel production

Cunwen WANG, Lu CHEN, Bajpai RAKESH, Yuanhang QIN, Renliang LV

期刊论文

Environmental and economic assessment of vegetable oil production using membrane separation and vapor recompression

Weibin Kong, Qi Miao, Peiyong Qin, Jan Baeyens, Tianwei Tan

期刊论文

离子液体在金属离子萃取中的研究进展

刘利梅,苏永庆,李琮,贺飞,何永福,钟云

期刊论文

Entity and relation extraction with rule-guided dictionary as domain knowledge

期刊论文

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

期刊论文

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

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

期刊论文

Deep eutectic solvent inclusions for high- composite dielectric elastomers

期刊论文

Purification of artemisinin from quercetin by anti-solvent crystallization

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

期刊论文

Review of solvent based carbon-dioxide capture technologies

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

期刊论文