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Optimization of Preparative Separation and Purification of Total Flavonoids from Radix Puerariae by Macroporous Resin Method 被引量:11
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作者 刘火安 王伯初 +3 位作者 戴传云 邵志勇 何从林 贾云 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第2期121-126,共6页
Aim To screen the optimum macroporous resin and conditions for the isolation and purification of flavonoids from Radix Puerariae. Methods The static and dynamic adsorption/desorption methods were used, and the separat... Aim To screen the optimum macroporous resin and conditions for the isolation and purification of flavonoids from Radix Puerariae. Methods The static and dynamic adsorption/desorption methods were used, and the separation and purification process was evaluated by measuring the concentration of total flavonoid in the fractions with UV spectrophotometer. Results The SP70 macroporous resin was the most effective compared with other macroporous resins. The optimum conditions were screened, which were 0.5 g· mL^- 1 corresponding to crude drug for concentration of extract, pH 5 - 6, and appended 60 times the volume of the resin bed (BV) with the adsorption speed 2 BV·h^-1, and the volume of aq. 70% (V/V) ethanol as eluant was 5 BV with desorption speed 2 BV·h^-1. By this method, the final contents of total flavonoids exceeded 80%. Conclusion The SP70 macroporous resin is the most effective one for large-scale isolation and purification of flavonoids from Radix Pueraria, which meets industrial needs. 展开更多
关键词 Radix Puerariae total flavonoids macroporous resin separation purification
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Separation and Purification of Recombinant Hirudin Variant 3 from Bacillus subtilis 被引量:7
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作者 陈华友 齐向辉 +1 位作者 耿旭 徐庆刚 《Agricultural Science & Technology》 CAS 2009年第6期15-19,共5页
[ Objective] The research aimed to get the optimized separation and purification conditions of the hirudin produced from Bacillus subtilis DB403 (pUBH5). [Method] Through the systemic pretreatment, preliminary chrom... [ Objective] The research aimed to get the optimized separation and purification conditions of the hirudin produced from Bacillus subtilis DB403 (pUBH5). [Method] Through the systemic pretreatment, preliminary chromatography and fine chromatography. [Result]The optimized separation and purification conditions were that: Supernatant was treated by trichloroacetic acid, then by ultrafiltration desalt and anion exchange chromatography. Strong anion Q F. F. was better than weak anion DEAE F.F. The proper balanced solution was Tris-HCI ( pH 8.0). The proper conductivity was 6 ms/cm. The maximum applied sample was 240 ATU/ml to matrix of strong anion Q F. F. This optimized procedure was magnified in strong anion exchange HiPrep 16/10Q with the 90% recovery and 70.2% purity. The purification of gel filtration of Sephacryl S-100 to hirudin was not relative to flow rate within certain scope. The application size of sample was 10 ml. The purity checked by HPLC was 95.1%, and the recovery was 93%, and the band of SDS-PAGE was single. [ Conclusion] The research provided the reference of the further industrialization separation and purification of hiruin. 展开更多
关键词 HIRUDIN Bacillus subtilis Ion exchange separation and purification
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Direct Ethylene Purification from Cracking Gas via a Metal–Organic Framework Through Pore Geometry Fitting
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作者 Yang Chen Zhenduo Wu +6 位作者 Longlong Fan Rajamani Krishna Hongliang Huang Yi Wang Qizhao Xiong Jinping Li Libo Li 《Engineering》 SCIE EI CAS CSCD 2024年第10期84-92,共9页
The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied f... The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied for precise regulation of the pore geometry of four tailor-made metal–organic frameworks(MOFs)with pillar-layered structures,dubbed TYUT-10/11/12/13.Based on its pore geometry design and functional group regulation,TYUT-12 exhibits exceptional selective adsorption selectivity toward C_(3)H_(8),C_(3)H_(6),C_(2)H_(6),C_(2)H_(2),and CO_(2) over C_(2)H_(4);its C_(2)H_(6)/C_(2)H_(4) adsorption selectivity reaches 4.56,surpassing the record value of 4.4 by Fe_(2)(O_(2))(dobdc)(dobdc^(4-)=2,5-dioxido-1,4-benzenedicarboxylate).The weak p–p stacking binding affinity toward C_(2)H_(4) in TYUT-12 is clearly demonstrated through a combination of neutron powder diffraction measurements and theoretical calculations.Breakthrough experiments demonstrate that C_(2)H_(4) can be directly obtained from binary,ternary,quaternary,and six-component light hydrocarbon mixtures with over 99.95%purity. 展开更多
关键词 Metal-organic frameworks Pore regulation Adsorptive separation One-step purification C_(2)H_(4)purification
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Separation and Purification of Antioxidant Endophytic Fungi from Stevia Leaves
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作者 王玉兵 郝再彬 +1 位作者 李海云 陈志良 《Agricultural Science & Technology》 CAS 2012年第1期123-126,142,共5页
[Objective] The aim was to separate and purify antioxidant endophytic fun- gi from Stevia leaves. [Method] Stevia leaves were used as materials for endophytic fungi screening and purification. Then, liquid culture was... [Objective] The aim was to separate and purify antioxidant endophytic fun- gi from Stevia leaves. [Method] Stevia leaves were used as materials for endophytic fungi screening and purification. Then, liquid culture was conducted to test fermented supernatant abilities of antioxidant, DPPH free radical clearing and chemilumines- cence inhibition. [Result] Forty two endophytic fungi were separated from F01 to F42. F41 was proved to be the strongest in antioxidant aspect; F37 was the strongest in DPPH clearing; F02, F07, F20, F25, F37, and F416 stood out in a comprehensive comparison of the above aspects. Flow injection chemiluminescenct method was used to test the above six fermentation liquors, and the results showed that antioxidant abilities of the six were quite strong for all of chemiluminescence rates were over 70%. Through preliminary morphological identification, bacterial colony was found white or yellowy and only F02 was of dissepiment. [Conclusion] Fungi with high-antioxidation activities were separated, which paved the way for future research. 展开更多
关键词 Stievia rebaudiana Endophytic fungi separation and purification ANTIOXIDANT
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Studies on Oxygen Characteristics of YBa_2Cu_3O_(7-x) and Its Applications to Air Separation and Gas Purification 被引量:4
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作者 杨德林 莫炯 +3 位作者 卢红霞 郭益群 高之爽 胡行 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第1期112-115,共4页
Oxygen diffusion and oxygen selective adsorption properties of rare earths material YBa_2Cu_3O_(7-x) (YBCO) were investigated by thermogravimetric, oxygen static adsorption and selectivity adsorption experiments. The ... Oxygen diffusion and oxygen selective adsorption properties of rare earths material YBa_2Cu_3O_(7-x) (YBCO) were investigated by thermogravimetric, oxygen static adsorption and selectivity adsorption experiments. The results show that YBCO is a very good deoxidizing material. The oxygen desorption of YBCO begins remarkably at about 400 ℃, mass loss can arrive at 1.2% of its original quantity at 800 ℃. Oxygen can be completely absorbed back into the sample again when temperature descends to 400 ℃. The oxygen adsorption selectivity, reproducibility and oxygen adsorption under very low oxygen partial pressure make the material desirable for air separation and gas purification. High purity nitrogen gas was produced with the YBCO molecular sieves in the air separation and gas purification experiments. 0.017 m^3 of high purity nitrogen (>99.9999%) can be obtained with 1 kg YBCO molecular sieve in one cycle. As a deoxidant, an obvious advantage of YBCO is that no hydrogen is needed in its applications. 展开更多
关键词 metal materials YBCO oxygen characters gas separation and purification rare earths
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Separation and purification of deoxynivalenol(DON) mycotoxin from wheat culture using a simple two-step silica gel column chromatography 被引量:7
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作者 ZHAO Xiu-mei LI Rong-jia +5 位作者 ZHOU Chuang ZHANG Jie HE Cheng-hua ZHENG Ya-ting WU Wen-da ZHANG Hai-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第3期694-701,共8页
Deoxynivalenol(DON) is a type B trichothecenes mycotoxin produced by several Fusarium species, often found in foodstuffs for humans and animals. DON is in great demand for the toxicological researches both in vivo a... Deoxynivalenol(DON) is a type B trichothecenes mycotoxin produced by several Fusarium species, often found in foodstuffs for humans and animals. DON is in great demand for the toxicological researches both in vivo and in vitro. In this work, wheat culture was inoculated with a Fusarium graminearum PH-1 strain for DON production. The solvent system for crude extraction was acetonitrile-water(84:16, v/v). A simple two-step silica gel column chromatography was employed to separate the DON mycotoxin from wheat culture, combined with preparative high performance liquid chromatography(preparative HPLC) to purify the compound. The solvent system for the second silica gel column chromatography was methylene chloride-methanol(17:1, v/v), which provided a good elution effect selected on thin layer chromatography(TLC). The target compound was identified by HPLC, and the chemical structure was confirmed by mass spectrometry(MS) and ~1H and ^(13)C nuclear magnetic resonance(NMR) spectroscopy. A total of 433 mg of purified DON was obtained from 1 kg of wheat culture, with a purity of 99.01%. The study had provided an easy-operating and cost-effective method to isolate an expensive compound in a simple way. 展开更多
关键词 deoxynivalenol silica gel column chromatography separation purification
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Review of Alloy Membranes/Films for Hydrogen Separation or Purification 被引量:1
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作者 王仲民 Li Vanessa Sammy Lap-Ip Chan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期611-616,共6页
Hydrogen separation and purification are two important chemical processes in the extensive application of hydrogen energy. Membrane technology has opened up a potential solution to the problems of separation and purif... Hydrogen separation and purification are two important chemical processes in the extensive application of hydrogen energy. Membrane technology has opened up a potential solution to the problems of separation and purification in an energy effective way. Membranes of adequate hydrogen permeability, good thermal and mechanical stability are the key to successful application of membrane technology in hydrogen separation and purification. In this paper, the relative parameters concerning hydrogen permeability, the development of different types of membranes namely: palladium composite membranes; V-based alloy membranes, specific functionality embraced alloy membranes, metal hydride (MH) thin films and fabrications, were reviewed and discussed. Pd-free membranes are found to be the ideal alternatives. Suitable MH thin films with mono- or multi-layer microstructures produced by novel fabrication techniques, is likely to be the promising candidates due to possessing properties distinct from those of bulk materials in membrane form. 展开更多
关键词 hydrogen separation and purification MEMBRANE thin film hydrogen permeability
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Separation and Purification of Total Phloroglucinols in Dryopteris crassirhizoma with DM-130 Macroporous Adsorption Resin 被引量:1
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作者 Jin Zhe Huang Jian-ping +3 位作者 Wang He-meng Ju han-xun Ren Si-rui Chang Ying 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第2期8-14,共7页
To improve the purity of the total phloroglucinols from Dryopteris crassirhizoma extracts, the separation and purification conditions of the total phloroglucinols from Dryopteris crassirhizoma were studied with DM-130... To improve the purity of the total phloroglucinols from Dryopteris crassirhizoma extracts, the separation and purification conditions of the total phloroglucinols from Dryopteris crassirhizoma were studied with DM-130 macroporous adsorption resin in this study. Adsorption rate, elution rate and purity of the total phloroglucinols were used as indexes to investigate the adsorption and desorption capacity of the total phloroglucinols with DM-130 macroporous adsorption resin. Through the study, the optimum sample concentration of the total phloroglucinols and maximum sample volume were 1.5 mg·mL^-1 and 7 BV (210 mL), respectively. The optimum desorption conditions were achieved by using 80% ethanol as desorption solvent at elution flow rate of 1.0 mL·min^-1. The result showed DM-130 macroporous adsorption resin performed effective adsorption and desorption. After purification, the purity of the total phloroglucinols increased by 11.5-fold. 展开更多
关键词 DM-130 adsorption resin Dryopteris crassirhizoma total phloroglucinols separation purification
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Separation and Purification of Monascus Pigments from Red Yeast Rice 被引量:1
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作者 Tongle LI Xiuhe LIU Li YAN 《Agricultural Biotechnology》 CAS 2019年第2期177-178,184,共3页
It is difficult to extract beneficial components from Monascus pigments due to their complex composition. The low purity of Monascus pigment preparations limits their further application in research and production. Th... It is difficult to extract beneficial components from Monascus pigments due to their complex composition. The low purity of Monascus pigment preparations limits their further application in research and production. Therefore, this study was conducted to optimize the conditions for extraction and isolation of Monascus pigments from red yeast rice, to improve the purity of Monascus pigment preparations. Three fractions were isolated using column chromatography from red yeast rice, they were red, orange and yellow respectively. Then, the three fractions were analyzed for composition and purity using thin layer chromatography and liquid chromatography-mass spectrometry(LC-MS). The chromatograms revealed that the yellow and orange fractions had complex compositions that were difficult to be separated, while the red fraction consisted of fewer components. Finally, a single component was isolated from the red fraction using a thin layer chromatography plate, identified as monascorubramine according to its molecular mass. 展开更多
关键词 MONASCUS PIGMENTS separation purification Monascorubramine
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Separation and Purification of Dodecanedioic Acid from Its Homologous Compounds by Falling Film Crystallization 被引量:1
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作者 李裕 刘有智 齐雪琴 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第3期451-453,共3页
Separation and purification of dodecanedioic acid (DDDA) from its homologous compounds were studied experimentally by falling film crystallization (FFC). The influences of various operation parameters, including cryst... Separation and purification of dodecanedioic acid (DDDA) from its homologous compounds were studied experimentally by falling film crystallization (FFC). The influences of various operation parameters, including crystallizing time, flow rate of melt and temperature of glycerine bath, on purity of DDDA and crystallizing rate were investigated. Over 99% (by mole) DDDA was obtained for a feed composition of 96% (by mole). The main factors affecting the separation efficiency are flow rate of melt and temperature of glycerine bath. The crystallizing layer of DDDA was further purified by sweating and blasting. A set of optimized operation data are provided for better understanding the mechanism of heat and mass transfer in FFC, and for further industrial application of DDDA purification process. 展开更多
关键词 dodecanedioic acid homologous compound falling film crystallization separation purification
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Design and optimization of an integrated process for the purification of propylene oxide and the separation of propylene glycol by-product 被引量:1
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作者 Song Hu Jinlong Li +1 位作者 Qihua Wang Weisheng Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第5期111-120,共10页
It is difficult to separate the methanol and hydrocarbons in the propylene oxide(PO)purification process due to their forming azeotrope.As for this,a novel PO separation process,in that the deionized water is employed... It is difficult to separate the methanol and hydrocarbons in the propylene oxide(PO)purification process due to their forming azeotrope.As for this,a novel PO separation process,in that the deionized water is employed as extractant and 1,2-propylene glycol(MPG)that is formed from the PO hydrolysis reaction is recovered,is presented in this work.The salient feature of this process is that both the non-catalyzed reactions of PO hydrolysis to form MPG and dipropylene glycol(DPG)are simultaneously considered and MPG by-product with high purity is obtained in virtue of the deionized water as reflux liquid and side take-off in MPG column.In addition,the ionic liquid(IL)extractant is screened through the conductorlike screening model for segment activity coefficient(COSMO-SAC)and the comparisons of separation efficiency between the IL and normal octane(nC_(8))extractant for the separation of PO and 2-methylpentane are made.With the non-random two-liquid(NRTL)thermodynamic model,the simulation and optimization design for the full flow sheet are performed and the effects of the key operation parameters such as solvent ratio,theoretical stages,feeding stage etc.on separation efficiency are detailedly discussed.The results show that the mass purity and the mass yield of PO can be up to 99.99%and 99.0%,and the condenser duty,reboiler duty and PO loss in the process with IL extractant can be decreased by 69.66%,30.21%and 78.86%compared to ones with nC_(8).The total annual cost(TAC)calculation also suggests that the TAC would be significantly reduced if using IL in replace of nC_(8) for the investigated process.The presented results would provide a useful guide for improving the quality of PO product and the economic efficiency of industrial plant. 展开更多
关键词 Propylene oxide purification Ionic liquids separation Extractive distillation HYDROLYSIS 1 2-propylene glycol
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KAOLIN CLAY PURIFICATION BY DRY HIGH GRADIENT MAGNETIC SEPARATION
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作者 Zhu, Dehua Sun, Zhongyuan Chen, Jin Central South University of Technology, Changsha 410083, China Chen, Zhengxue Changsha Research Institute of Mining and Metallurgy 《中国有色金属学会会刊:英文版》 CSCD 1993年第1期22-26,共5页
A new method-dry High Gradient Magnetic Separation (HGMS)-to remove iron from ultrafine kaolin powder is described. A new kind of disperser, which breaks down the particle clusters in the powder by high speed gas fl... A new method-dry High Gradient Magnetic Separation (HGMS)-to remove iron from ultrafine kaolin powder is described. A new kind of disperser, which breaks down the particle clusters in the powder by high speed gas flow from an air compressor, is used to completely disperse the powders. The dispersed particles are passed through vibrating HGMS by a vacuum pump to remove the iron. The magnetic and nonmagnetic fractions are separately collected by cloth collectors. Dry HGMS laboratory experiments are carried out. A product containing 0.90% Fe<sub>2</sub>O<sub>3</sub> was obtained, and the recovery was 70%. 展开更多
关键词 MAGNETIC separation KAOLIN purification DRY high GRADIENT MAGNETIC separATOR
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Advances in Researches of Extraction, Separation, and Purification Technologies for Total Saponins of Panax notoginseng
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作者 Hongyi CHEN Changmin GAN Yunqi GONG 《Medicinal Plant》 CAS 2019年第4期1-4,共4页
Total saponins of Panax notoginseng have the functions of promoting blood circulation and removing phlegm, thus they have high medicinal value. There are many different extraction methods in the extraction and separat... Total saponins of Panax notoginseng have the functions of promoting blood circulation and removing phlegm, thus they have high medicinal value. There are many different extraction methods in the extraction and separation of total saponins of P. notoginseng . The extraction methods of total saponins of P. notoginseng are mainly divided into traditional extraction methods, modern extraction methods and compound extraction methods. 展开更多
关键词 Total SAPONINS of PANAX notoginseng separation and purification TECHNOLOGIES EXTRACTION TECHNOLOGIES
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Separation and purification of proteinases from Gastric Mucosa of Northern Sheatfish,Silurus soldatovi
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作者 刘伟 张秀梅 +1 位作者 战培荣 张照韩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第3期62-67,共6页
The separation and purification method for pepsin of Northern Sheatfish (Silurus soldatovi) was established by using the combination technology of salting-out,gel chromatography and gel electrophoresis,and the enzymic... The separation and purification method for pepsin of Northern Sheatfish (Silurus soldatovi) was established by using the combination technology of salting-out,gel chromatography and gel electrophoresis,and the enzymic properties were also analyzed.The experimental results indicated that 28% and 56% (NH4)2SO4 saturation could separate the activated protease from the pepsin extract of gastric mucosa of Sheatfish (Silurus soldatovi) ;compared with the homogenate extraction,the pepsin specific activity of purified extraction by Sephadex G-75 gel chromatography system increased 598 fold,was 5 times higher than that of activated liquid,and the total production rate was 10.1%.The purified pepsin liquor at the conditions of pH3.3 0.01 M alanine-formic acid buffering solution,60 cm chromatography column,and the flowing rate of 0.8 ML/min was analyzed by SDS-PAGE,which indicated that there were two bands and the molecular weight was 34.0 kDa and 40.4 kDa,respectively.There were two peaks in the enzyme activity determination of the separated collecting liquor in gel chromatography,and the SDS-PAGE showed the concentrations of the two proteins was different,which indicated that it existed at least two pepsins in the gastric mucosa of Sheatfish (Silurus soldatovi). 展开更多
关键词 Sheatfish (Silurus soldatovi) PEPSIN separation and purification PROPERTY
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Separation and Purification of Tobacco Peroxidase I from Nicotiana Tobaccum
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作者 夏炳乐 刘清亮 +3 位作者 李敏莉 徐小龙 施春华 解永树 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第3期341-343,共3页
A new isoenzyme of tobacco peroxidase(TOP) I was purified from tobacco (K326) by using acetone powder, ammonium sulfate precipitation and column chromatography on DEAE-52 cellulose, Sephadex G-75 and DEAE-Sephadex A-5... A new isoenzyme of tobacco peroxidase(TOP) I was purified from tobacco (K326) by using acetone powder, ammonium sulfate precipitation and column chromatography on DEAE-52 cellulose, Sephadex G-75 and DEAE-Sephadex A-50. It is an iron-protein containing haemachrome, whose molecular weight is 21888.5 and the isoelectric point is 3.5. The optimum pH value and temperature of this enzyme is 6.0 and 45℃respectively. The enzyme is stable in the pH range from 3.0 to 10.0 and has a favorable thermostability. 展开更多
关键词 tobacco peroxidase separation purification
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Separation and Purification of GST-glycerol-3-phosphate Dehydrogenase
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作者 Hongmei ZHAO Shihai LI Yasuo WATANABE 《Agricultural Biotechnology》 CAS 2016年第5期44-45,共2页
In order to investigate the expression of glycerol-3 -phosphate dehydrogenase by GCY1 gene in recombinant Saccharomyces cerevisiae, induction culture of the S. cerevisiaestrain was performed with SD-URA 2% galactose, ... In order to investigate the expression of glycerol-3 -phosphate dehydrogenase by GCY1 gene in recombinant Saccharomyces cerevisiae, induction culture of the S. cerevisiaestrain was performed with SD-URA 2% galactose, 3 × YP + 6% glucose, SC-URA 2% galactose, and SC-URA 2% galactose + 5% NaCI glyeerol-3-phosphate dehydregenase, the cultured S. cerevisiaewas comminuted followed by full-automatic high-speed purification, and SDS-PAGE gel electrophoresis was performed for molecular weight of the GST fusion protein. The results showed that after shaking culture of the S. cerevisiae containing GCY1 at 25 ℃, the OD values of its 3 × YP + 6% glucose culture and SC-URA 2% galaetose + 5% NaC1 culture were 8.75 and 7.35, respectively. It was shown by purification with a Profinia low-pressure liquid chromatograph that only the S. cerevisiae cultured in SC-URA 2% galactose + 5% NaC1 medium expressed glycerel-3-phosphate de- hydrogenase, the molecular weight of which was detected as 65 ku by SDS-PAGE gel electrophoresis. 展开更多
关键词 Saccharomyces cerevisiae Glycerol-3-phosphate dehydrogenase GALACTOSE SDS-PAGE gel electrophoresis separation and purification
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Experiments and model development of p-nitrochlorobenzene and naphthalene purification in a continuous tower melting crystallizer
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作者 Wenlong Xiao Yonglin Li +2 位作者 Zhengming Yi Sheng Yang He’an Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期9-17,共9页
With the increasing demand for high-purity products,the industrial application of melt crystallization technology has been highly concerned.In this study,the purification process of nitrochlorobenzene binary eutectic ... With the increasing demand for high-purity products,the industrial application of melt crystallization technology has been highly concerned.In this study,the purification process of nitrochlorobenzene binary eutectic system(NBES)and naphthalene–benzothiophene solid solution system(NBSSS)in tower melting crystallizer is analyzed,and a mathematical model of crystallization process is established.The key parameters in terms of feed concentration,crystal bed height,reflux ratio and stirring speed effi-ciency on purification effects were discussed by the established model.The results show that the concentration of p-nitrochlorobenzene was purified from 90.85%to 99.99%,when the crystal bed height is 600 mm,the reflux ratio is 2.5,and the stirring speed is 12 rmin^(-1).The naphthalene concentration is purified from 95.89%to 99.99%,when the crystal bed height is 400 mm,the reflux ratio is 1.43,and the stirring speed is 16 rmin^(-1).The quality of the model is evaluated by the ARD(average relative deviation).The minimum ARD values of the NBES and NBSSS are 2.39%and 5.22%,respectively,indicating the model satisfactorily explains the purification process. 展开更多
关键词 CRYSTALLIZATION separation Mathematical modeling CRYSTALLIZER purification
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One-step ethylene separation from ternary C_(2) hydrocarbon mixture with a robust zirconium metal-organic framework
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作者 Yuan Liu Hanting Xiong +5 位作者 Jingwen Chen Shixia Chen Zhenyu Zhou Zheling Zeng Shuguang Deng Jun Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期9-15,共7页
One-step separation of high-purity ethylene(C_(2)H_(4))from C_(2) hydrocarbon mixture is critical but challenging because of the very similar molecular sizes and physical properties of C_(2)H_(4),ethane(C_(2)H_(6)),an... One-step separation of high-purity ethylene(C_(2)H_(4))from C_(2) hydrocarbon mixture is critical but challenging because of the very similar molecular sizes and physical properties of C_(2)H_(4),ethane(C_(2)H_(6)),and acetylene(C_(2)H_(2)).Herein,we report a robust zirconium metal-organic framework(MOF)Zr-TCA(H3TCA=4,4',4"-tricarboxytriphenylamine)with suitable pore size(0.6 nm×0.7 nm)and pore environment for direct C_(2)H_(4) purification from C_(2)H_(4)/C_(2)H_(2)/C_(2)H_(6) gas-mixture.Computational studies indicate that the abundant oxygen atoms and non-polar phenyl rings created favorable pore environments for the preferential binding of C_(2)H_(2) and C_(2)H_(6) over C_(2)H_(4).As a result,Zr-TCA exhibits not only high C_(2)H_(6)(2.28 mmol·g^(-1))and C_(2)H_(2)(2.78 mmol·g^(-1))adsorption capacity but also excellent C_(2)H_(6)/C_(2)H_(4)(2.72)and C_(2)H_(2)/C_(2)H_(4)(5.64)selectivity,surpassing most of one-step C_(2)H_(4) purification MOF materials.Dynamic breakthrough experiments confirm that Zr-TCA can produce high-purity C_(2)H_(4)(>99.9%)from a ternary gas mixture(1/9/90 C_(2)H_(2)/C_(2)H_(6)/C_(2)H_(4))in a single step with a high C_(2)H_(4) productivity of 5.61 L·kg^(-1). 展开更多
关键词 Zirconium metal-organic framework Adsorption separation One-step ethylene purification
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Ethylene purification in a metal–organic framework over a wide temperature range via pore confinement
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作者 Xue-Qian Wu Peng-Dan Zhang +4 位作者 Xin Zhang Jing-Hao Liu Tao He Jiamei Yu Jian-Rong Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1703-1710,共8页
The separation of C2H4from C_(2)H_(6)/C_(2)H_(4)mixture is of great importance but difficult and energy intensive. Adsorptive separation provides an alternative approach to ameliorate this situation. Here, we report a... The separation of C2H4from C_(2)H_(6)/C_(2)H_(4)mixture is of great importance but difficult and energy intensive. Adsorptive separation provides an alternative approach to ameliorate this situation. Here, we report a microporous metal–organic framework(MOF) BUT-315-a as a C_(2)H_(6)-selective adsorbent for the separation of C2H6/C2H4gas mixture. BUT-315-a combines good IAST selectivity of 2.35 with high C_(2)H_(6)uptake of 97.5 cm^(3)g^(-1), giving superior high separation potential ΔQ(2226 mmol L^(-1)) for equimolar C_(2)H_(6)/C_(2)H_(4) at 298 K. Impressively, such excellent performance can be preserved at higher temperatures of 313 and 323 K to accommodate industrial conditions. Efficient dynamic separation performance of BUT-315-a has been demonstrated by column breakthrough experiments under varied temperatures and gas ratios. Theoretical calculations further reveal multiple synergistic interactions between C_(2)H_(6) and the framework. This work highlights a new benchmark material for C_(2)H_(6)/C_(2)H_(4)separation and provides guidance for designing adsorbent for separation applications. 展开更多
关键词 Metal–organic framework Adsorptive separation Ethylene purification Temperature adaptability Pore confinement
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Structure identification for compound I separated and purified from taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011)
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作者 项勇 刘君 +1 位作者 呂安国 崔京霞 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期217-220,共4页
Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physio... Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active com-pounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source. Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type III, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a com-pleted method for separation and purification of the endophytic fungi as well as structure identification of its fermentation me-tabolite 展开更多
关键词 Alternaria. Alternata var. taxi 1011 TAXOIDS separation purification Structure identification
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