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Simultaneous catalytic hydrolysis of carbonyl sulfide and carbon disulfide over Al_2O_3-K/CAC catalyst at low temperature 被引量:8
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作者 Xin Sun Ping Ning +6 位作者 Xiaolong Tang Honghong Yi Kai Li Dan He Xianmang Xu Bin Huang Ruiyun Lai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期221-226,共6页
In this work, a series of coal-based active carbon (CAC) catalysts loaded by A1203 were prepared by sol-gel method and used for the simulta- neous catalytic hydrolysis of carbonyl sulfide (COS) and carbon disulfi... In this work, a series of coal-based active carbon (CAC) catalysts loaded by A1203 were prepared by sol-gel method and used for the simulta- neous catalytic hydrolysis of carbonyl sulfide (COS) and carbon disulfide (CS2) at relatively low temperatures of 30-70 ℃. The influences of calcinations temperatures and operation conditions such as: reaction temperature, 02 concentration, gas hourly space velocity (GHSV) and relative humidity (RH) were also discussed respectively. The results showed that catalysts with 5.0 wt% A1203 calcined at 300 ℃ had supe- rior activity for the simultaneous catalytic hydrolysis of COS and CS2. When the reaction temperature was above 50 ℃, catalytic hydrolysis activity of COS could be enhanced but that of CS2 was inhibited. Too high RH could make the catalytic hydrolysis activities of COS and CS2 decrease. A small amount of 02 introduction could enhance the simultaneous catalytic hydrolysis activities of COS and CS2. 展开更多
关键词 carbonyl sulfide carbon disulfide simultaneous catalytic hydrolysis Al2O3-K/CAC catalysts
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Definition, theory, methods, and applications of the safe and efficient simultaneous extraction of coal and gas 被引量:36
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作者 Yuanping Cheng Liang Wang +3 位作者 Hongyong Liu Shengli Kong Jintuo Zhu Qingyi Tu 《International Journal of Coal Science & Technology》 EI 2015年第1期52-65,共14页
Simultaneous extraction of the coal and gas is an effective method of eliminating coal mine gas disasters while safely exploiting the coal and achieving efficient gas drainage in China, which is widely accepted by the... Simultaneous extraction of the coal and gas is an effective method of eliminating coal mine gas disasters while safely exploiting the coal and achieving efficient gas drainage in China, which is widely accepted by the main coal-producing countries around the world. However, the concrete definition of simultaneous extraction is vague and there is little accurate theoretical support for the simultaneous extraction of coal and gas, which makes it difficult to determine an efficient gas drainage method appropriate to the features of coal seams. Based on theoretical analysis, laboratory tests and field observations, a specific definition of simultaneous extraction of coal and gas is proposed after analyzing the characteristics of coal seam occurrences in China, and we developed the mechanism of mining-enhanced permeability and established the corresponding theoretical model. This comprises a process of fracture network formation, in which the original fractures are opened and new fractures are produced by unloading damage. According to the theoretical model, the engineering approaches and their quantitative parameters of 'unloading by borehole drilling' for single coal seams and 'unloading by protective seam mining' for groups of coal seams are proposed, and the construction principles for coal exploitation and gas-drainage systems for different conditions are given. These methods were applied successfully in the Tunlan Coal Mine in Shanxi Province and the Panyi Coal Mine in Anhui Province and could assure safe and efficient simultaneous extraction of coal and gas in these outburst coal mines. 展开更多
关键词 Coal seam gas Outburst coal seam Mining-enhanced permeability simultaneous extraction of coal and gas
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Comparison of simultaneous distillation extraction and solid-phase micro-extraction for determination of volatile constituents in tobacco flavor 被引量:8
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作者 钟科军 魏万之 +1 位作者 郭方遒 黄兰芳 《Journal of Central South University of Technology》 EI 2005年第5期546-551,共6页
The volatile and semi-volatile components in tobacco flavor additives were extracted by both simultaneous distillation extraction and solid-phase micro-extraction. Extraction conditions for solid-phase micro-extractio... The volatile and semi-volatile components in tobacco flavor additives were extracted by both simultaneous distillation extraction and solid-phase micro-extraction. Extraction conditions for solid-phase micro-extraction were optimized with information theory. Then, detection were accomplished by gas chromatography-mass spectrometry. Characteristic of each method was compared. Qualitative analysis and quantitative analysis of 6# tobacco flavor sample were accomplished through both simultaneous distillation extraction and solid-phase micro-extraction. The experimental results show that solid-phase micro-extraction method is the first choice for qualitative analysis and simultaneous distillation extraction is another good selection for quantitative analysis. By means of simultaneous distillation extraction, 20 components are identified, accounting for 92.77% of the total peak areas. Through solid-phase micro-extraction, there are 17 components identified accounting for 91.49% of the total peak areas. The main aromatic components in 6# tobacco flavor sample are propanoic acid, 2-hydroxy-, ethyl ester, menthol and menthyl acetate. The presented method has been successfully used for quality control of tobacco flavor. 展开更多
关键词 simultaneous distillation extraction solid-phase micro-extraction gas chromatography-mass spectrometry tobacco flavor
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Comparison of volatile and semivolatile compounds from commercial cigarette by supercritical fluid extraction and simultaneous distillation extraction 被引量:5
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作者 徐子刚 郑琳 《Journal of Zhejiang University Science》 EI CSCD 2004年第12期1528-1532,共5页
Supercritical carbon dioxide fluid extraction (SFE) was studied as a rapid method for extraction of volatile and semivolatile compounds of Chinese commercial cigarettes. The method was compared with simultaneous disti... Supercritical carbon dioxide fluid extraction (SFE) was studied as a rapid method for extraction of volatile and semivolatile compounds of Chinese commercial cigarettes. The method was compared with simultaneous distillation and extraction (SDE). Temperature and pressure for the SFE were optimized. The extracts obtained by the two methods showed different characters in composition and represented differently the flavor characteristics of tobacco; compared to SDE, SFE can extract compounds within a shorter time and avoid the thermal degradation and solvent contamination of samples. The extracts by the two extraction methods are complementary for investigating the flavor characteristic of tobacco products. 展开更多
关键词 Volatile and semivolatile compounds Commercial cigarette Supercritical fluid extraction (SFE) simultaneous distillation extraction (SDE)
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Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry 被引量:4
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作者 SHAN Xiao Mei SHEN Deng Hui +2 位作者 WANG Bing Shuang LU Bei Bei HUANG Fa Yuan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第6期471-474,共4页
To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry ... To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry (UPLC/MS/MS). The water samples were extracted and condensed with solid-phase extraction (SPE) using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%. 展开更多
关键词 UPLC BPA simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry MASS
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Comparison of Headspace Solid-Phase Microextraction with Simultaneous Steam Distillation Extraction for the Analysis of the Volatile Constituents in Chinese Apricot 被引量:20
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作者 CHEN Mei-xia CHEN Xue-sen +4 位作者 WANG Xin-guo CI Zhi-juan LIU Xiao-li HE Tian-ming ZHANG Li-jie 《Agricultural Sciences in China》 CAS CSCD 2006年第11期879-884,共6页
Volatile constituents in fully mature fruits of apricot (Prunus armeniaca L.) cultivar Xinshiji were extracted using headspace solid-phase microextraction (HS-SPME) and simultaneous steam distillation extraction ... Volatile constituents in fully mature fruits of apricot (Prunus armeniaca L.) cultivar Xinshiji were extracted using headspace solid-phase microextraction (HS-SPME) and simultaneous steam distillation extraction (SSDE) and then analyzed using capillary gas chromatography and gas chromatography-mass spectrometry. A total of 70 components were identified by HSSPME, including 20 esters, 19 hydrocarbons, 5 alcohols, 5 ketones, 4 acids, 4 lactones, 3 aldehydes, and 10 miscellaneous components, with the esters being the dominant constituent. On the basis of the odor unit values, it is believed that the following compounds probably contributed to the fresh apricot odor: hexyl acetate, β-ionone, butyl acetate, (E)-2-hexenal, linalool, limonene, γ-decalactone, and hexanal. A total of 49 components were also detected by SSDE, including 13 hydrocarbons, 9 alcohols, 7 aldehydes, 9 esters, 4 ketones, 4 lactones, 2 acids, and 1 miscellaneous component, of which the monoterpene alcohols were the dominant constituents. It could be judged from the odor unit values that the following compounds were the major contributors to boiled apricot aroma: β-ionone, linalool, hexyl acetate, γ-dodecalactone, γ- decalactone, (E)-2-hexenal, hexanal, γ-octalactone, phenylacetaldehyde, butyl acetate, limonene, α-terpineol, and δ-decalactone. The results show that HS-SPME is a simple, rapid, and solvent-free method, which is an alternative to the classical SSDE. 展开更多
关键词 AROMA volatile constituents APRICOT solid-phase microextraction simultaneous distillation-extraction
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Extraction Hydrolysates from Larimichthys Polyactis Swim Bladder Using Enzymatic Hydrolysis
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作者 Ling Pan Yubo Tao Peng Li 《Journal of Renewable Materials》 SCIE EI 2021年第6期1099-1109,共11页
As a kind of biopolymer,hydrolysates of fish swim bladder,safer than those of land mammals,are widely used in food,cosmetics as well as pharmaceutical and biomedical fields for their biocompatibility,biodegradability,... As a kind of biopolymer,hydrolysates of fish swim bladder,safer than those of land mammals,are widely used in food,cosmetics as well as pharmaceutical and biomedical fields for their biocompatibility,biodegradability,and weak antigenicity.To enhance hydrolysate production,in this paper,the papain and alcalase hydrolysis processes of larimichthys polyactis swim bladder were optimized with orthogonal experiments.With 89.5%hydrolysate yield,the optimal processing conditions for alcalase were solid-liquid ratio of 1:30,enzyme concentration of 0.7%,and extraction time of 6 h.As for papain,under the optimal processing conditions:solid-liquid ratio of 1:20,enzyme concentration of 0.5%,and extraction time of 8 h,the hydrolysate yield was 65.1%.To obtain higher hydrolysate yields,the ultrasonic pretreatments were implemented before the optimal enzyme hydrolysis processes.With ultrasonic waves of 100 W for 50 min,the hydrolysate yields were increased 2.1%(alcalase)and 4.5%(papain),respectively.The Fourier Transform Infrared(FTIR)spectroscopic analysis revealed that the hydrolysates extracted by papain exist in triple-helical forms.The Ultra-Violet(UV)absorption spectra indicated that the aromatic amino acids in the hydrolysates had strong absorptions in the wavelength range of 240 nm–300 nm.The results of this research demonstrate that the alcalase hydrolysates have better solubility in water and the solution is more stable under ambient temperature.However,the hydrolysates extracted by papain have a gel property and are insoluble in weak acid at room temperature,which is more suitable for applications in feedstock of biomedical. 展开更多
关键词 Swim bladder enzymatic hydrolysis ultrasonic-assisted extraction hydrolysates analysis
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Current situation of simultaneous coal and methane extraction tech- nology in pressure-relieved coalbed group
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作者 Feng CAI Ze-Gong LIU Yi LUO 《Journal of Coal Science & Engineering(China)》 2013年第4期500-506,共7页
The importance of simultaneous coal and methane extraction and its significance on green exploitation is stated, and current research situation of simultaneous coal and methane and faced new problems are introduced. T... The importance of simultaneous coal and methane extraction and its significance on green exploitation is stated, and current research situation of simultaneous coal and methane and faced new problems are introduced. The research progress on movement of overlying strata and stresses change in them, cracks development during mining in overlying strata and meth- ane emission under disturbance of mining as well as the changing rules of permeability and methane flow under the disturbance of mining is analyzed. The progress on practice of simultaneous coal and methane extraction is analyzed. The deficiencies of current research and further researching fields on simultaneous coal and methane extraction are pointed out. 展开更多
关键词 simultaneous coal and methane extraction pressure-relieved methane coalbed methane methane drainage
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Process Research on Separate Hydrolysis and Fermentation(SHF) and Simultaneous Saccharification and Fermentation(SSF) of Ethanol Production by Lignocellulose
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作者 HUA Xin-yi LI Jin-jun HU Bao-an 《Meteorological and Environmental Research》 2012年第6期55-57,共3页
[ Objective] The research aimed to explore the efficiency of ethanol production under the optimal conditions of separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). ... [ Objective] The research aimed to explore the efficiency of ethanol production under the optimal conditions of separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). [ Method ] Under the optimal conditions of hydrolysis and fermenta- tion, SHF and SSF process were designed respectively. SHF process was conducted under the optimal conditions of hydrolysis and fermentation separately, while SSF process was carried out at the optimum temperature of hydrolysis and fermentation. [ Result] In SHF process, the efficiency of ethanol production was similar during both supematant and mixture fermentation, and yeast was more active during the mixture fermentation. In SSF process, the efficiency of ethanol production was higher at 35 ℃, and the production of xylose was higher than that in hydrolysis process. [ Conclusion] Under the experimental conditions, the efficiency of ethanol production during simultaneous saccharification and fermentation was higher than that during separate hydrolysis and fermentation. 展开更多
关键词 simultaneous saccharification and fermentation Separate hydrolysis and fermentation ETHANOL China
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FEASIBILITY ANALYSIS OF SAFETY SIMULTANEOUS EXTRACTION OF COAL AND COALBED METHANE 被引量:2
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作者 李树刚 《Journal of Coal Science & Engineering(China)》 2000年第1期52-56,共5页
Coalbed methane is of great value to extract and utilize in China, but the result of such research is not satisfied yet today.The paper analyzed the storage characteristics of coalbed methane, and then studied the beh... Coalbed methane is of great value to extract and utilize in China, but the result of such research is not satisfied yet today.The paper analyzed the storage characteristics of coalbed methane, and then studied the behavior of coalbed methane using the key stratum theory of strata control.According to the features related to coalbed methane accumulations and delivery, the technique for safely simultaneous extraction of coal and coalbed methane is proposed, and benefit analysis is made too. 展开更多
关键词 simultaneous extraction key stratum theory bed seperated fissure methane drainage BENEFIT
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Effectiveness and safety of early lens extraction during par plana vitrectomy for proliferative diabetes retinopathy with mild cataract:a randomized clinical trial
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作者 Wei-Bo Feng Lei Zheng +17 位作者 Ying-Qi Li Yong-Hao Li Guo-Ming Zhang Xian Wang Bing-Qian Liu Ling Jin Yi-Nuo Huang Yang-Fan Yang Zi-Dong Chen Da-Hui Ma Qing-Shan Chen Chao-Jun Qin Bing-Min Feng Zhu-Min Yang Xing Huang Cheng-Jie Yang Sheng-Hui Liu Ming-Xing Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期528-536,共9页
●AIM:To evaluate the effectiveness and safety of early lens extraction during pars plana vitrectomy(PPV)for proliferative diabetic retinopathy(PDR)compared to those of PPV with subsequent cataract surgery.●METHODS:T... ●AIM:To evaluate the effectiveness and safety of early lens extraction during pars plana vitrectomy(PPV)for proliferative diabetic retinopathy(PDR)compared to those of PPV with subsequent cataract surgery.●METHODS:This multicenter randomized controlled trial was conducted in three Chinese hospitals on patients with PDR,aged>45y,with mild cataracts.The participants were randomly assigned to the combined(PPV combined with simultaneously cataract surgery,i.e.,phacovitrectomy)or subsequent(PPV with subsequent cataract surgery 6mo later)group and followed up for 12mo.The primary outcome was the change in best-corrected visual acuity(BCVA)from baseline to 6mo,and the secondary outcomes included complication rates and medical expenses.●RESULTS:In total,129 patients with PDR were recruited and equally randomized(66 and 63 in the combined and subsequent groups respectively).The change in BCVA in the combined group[mean,36.90 letters;95%confidence interval(CI),30.35–43.45]was significantly better(adjusted difference,16.43;95%CI,8.77–24.08;P<0.001)than in the subsequent group(mean,22.40 letters;95%CI,15.55–29.24)6mo after the PPV,with no significant difference between the two groups at 12mo.The overall surgical risk of two sequential surgeries was significantly higher than that of the combined surgery for neovascular glaucoma(17.65%vs 3.77%,P=0.005).No significant differences were found in the photocoagulation spots,surgical time,and economic expenses between two groups.In the subsequent group,the duration of work incapacity(22.54±9.11d)was significantly longer(P<0.001)than that of the combined group(12.44±6.48d).●CONCLUSION:PDR patients aged over 45y with mild cataract can also benefit from early lens extraction during PPV with gratifying effectiveness,safety and convenience,compared to sequential surgeries. 展开更多
关键词 lens extraction pars plana vitrectomy proliferative diabetic retinopathy CATARACT simultaneously operations
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Characterization of stereostructure by X-ray and technology of extracting in combination hydrolysis in situ of acankoreanogenin from leaves of Acanthopanax gracilistylus W.W.Smith 被引量:1
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作者 戴玲 刘向前 +1 位作者 谢霞 刘恒言 《Journal of Central South University》 SCIE EI CAS 2014年第8期3063-3070,共8页
To study the stereostructure by X-ray and the technology of extracting acankoreanogenin from the leaves of Acanthopanax graeilistylus W. W. Smith (AGS), the crystal structure was measured with a Bruker APEX-Ⅱ area-... To study the stereostructure by X-ray and the technology of extracting acankoreanogenin from the leaves of Acanthopanax graeilistylus W. W. Smith (AGS), the crystal structure was measured with a Bruker APEX-Ⅱ area-detector diffractometer instrument and the technology of extracting in combination hydrolysis in situ (ECHS) was compared with these of traditional methods. The crystal belongs to the monoclinic system, space group P2b with unit cell parameters: a=(8.3652±0.0006) nm, b=(24.721±0.002) nm, and c=(14.5587±0.0011) nm, α=90°, β=97.850 (4) °, γ=90 °, V=2982.51 nm3, Dc= 1.179 mg/m3, and the molecular number (Z) of elementary structures was 2. The comparisons show that the extraction rate of acankoreanogenin with ECHS methods is much higher than that of traditional methods. Then, central composite design-response surface methodology (CCD-RSM) was adopted for optimizing the extraction rate of ECHS methods. The optimized values of extraction parameters are as follows: for the for extraction process of acid hydrolysis are that extraction time 110.8 min, solvent-herb ratio 11.5 and acid content 5.25%; the best extraction process of basic hydrolysis are that extract time 120 min, solvent-herb ratio 8.7 and the alkali content 8.79%. Finally, the extracts were purified with decolorizing carbon after alkali solution and acid-isolation and purity of acankoreanogenin was 98.7%. 展开更多
关键词 acankoreanogenin extraction in combination hydrolysis in situ Acanthopanax gracilistylus W. W. Smith (AGS) centralcomposite design-response surface methodology
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Acid volatile sulfide and simultaneously extracted metals in superficial sediments from Baihua Lake, China
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作者 章吉萍 胡继伟 +4 位作者 黄先飞 沈威 金梅 付丽亚 靳小飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1079-1087,共9页
The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs... The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs) to acid volatile sulfide (AVS). Atomic absorption spectrometry (AAS) and X-ray powder diffraction (XRD) were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g (dry weight). The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake. 展开更多
关键词 Baihua Lake SEDIMENTS acid volatile sulfides simultaneously extracted metals BIOAVAILABILITY
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Alleviation of Drought Stress in Wheat Using Exogenous Ulva prolifera Extract Produced by Enzymatic Hydrolysis
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作者 Feiyu Li Siqi Zuo +5 位作者 Yongzhou Chi Chunying Du Zhaopeng Shen Xihong Han Xiaohui Wang Peng Wang 《Journal of Renewable Materials》 SCIE EI 2020年第11期1519-1529,共11页
Drought is one of the major abiotic stresses that affect plant growth and reduce agricultural productivity.Use of algal extract as a biostimulant is gaining increased attention from researchers.This study aimed to inv... Drought is one of the major abiotic stresses that affect plant growth and reduce agricultural productivity.Use of algal extract as a biostimulant is gaining increased attention from researchers.This study aimed to investigate the potential of Ulva prolifera extract(UE)as a biostimulant when enzymatically extracted under conditions of water deficit.UE treatments(0.02%,0.06%,and 0.1%)significantly improved the shoot length,root length,and dry weight of roots after 120 h of drought stress relative to that in treatment with the negative control.An increase in catalase(CAT)and peroxidase(POD)activity was also observed that resulted in improved antioxidant capacity.Application of 0.1%UE reduced the malondialdehyde(MDA)content by 30.06%compared with that in the negative control.In addition,the soluble sugar and protein content in wheat treated with 0.1%UE was increased by 23.10%and 93.51%,respectively,resulting in adjustment of the osmotic pressure.Results suggest that UE could significantly enhance the drought tolerance of wheat.This study provides a basis for increasing the value of UE as a biostimulant. 展开更多
关键词 Ulva prolifera extract enzymatic hydrolysis antioxidant capacity OSMOPROTECTANTS drought tolerance
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Selective extraction and conversion of lignin in actual biomass to monophenols: A review 被引量:7
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作者 Zhicheng Jiang Changwei Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期947-956,共10页
Our over dependency on the fossil resource for industrial chemicals and fuels faces great challenges. Recently, the production of monophenols from lignin in lignocellulosic biomass is regarded as a promising process f... Our over dependency on the fossil resource for industrial chemicals and fuels faces great challenges. Recently, the production of monophenols from lignin in lignocellulosic biomass is regarded as a promising process for sustainable biofuels. This article discusses the conversion of lignin in actual biomass directly to monophenols. The two step way including extraction of lignin from biomass and further degradation of the lignin oligomers to monophenols is especially discussed. The obtained monophenols can also be converted to chemicals with low-oxygen content via hydrodeoxygenation process. For extraction of lignin, co-solvent system is the most adopted for hydrolysis or solvolysis of lignin assisted by acid or alkaline catalysts. The structure of the obtained oligomers derived from lignin is discussed in detail. For lignin depolymerization, hydrogenolysis is an efficient method with the use of gaseous hydrogen or alcohols as hydrogen source. At the meantime, depolymerization mechanism and the route for repolymerization of the reaction intermediates are presented here. In hydrodeoxygenation process, metal catalysts, especially noble metal catalysts are required. The precise effects of the reaction solvents and catalysts on extraction and degradation of lignin need to be further investigated, and this will benefit to design more efficient strategies for lignin utilization. © 2016 Science Press 展开更多
关键词 BIOMASS CATALYSTS extraction hydrolysis Industrial chemicals OLIGOMERS Precious metals Reaction intermediates REVIEWS Solvents
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Optimization of Ultrasonic-enzymatic Extraction of Total Flavonoids from Cardamine tangutorum O.E.Schulz by Response Surface Methodology and Content Determination 被引量:2
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作者 Xiaoxia CAI Bochao LI +3 位作者 Xuexue LI Hongna SU Wenbing LI Yuan LIU 《Medicinal Plant》 CAS 2020年第6期36-41,共6页
[Objectives]This study aimed to optimize the extraction process of total flavonoids in Cardamine tangutorum O.E.Schulz.[Methods]On the basis of single-factor experiments,the ultrasonic-enzymatic extraction process of ... [Objectives]This study aimed to optimize the extraction process of total flavonoids in Cardamine tangutorum O.E.Schulz.[Methods]On the basis of single-factor experiments,the ultrasonic-enzymatic extraction process of total flavonoids in C.tangutorum O.E.Schulz was optimized by Box-Behnken design from aspects of ethanol volume fraction,extraction time,extraction temperature and enzyme addition,with yield of total flavonoids as the evaluation index.[Results]The optimal extraction process of total flavonoids in C.tangutorum O.E.Schulz was as follows:ethanol volume fraction of 70%,ultrasonic extraction time of 43 min,ultrasonic extraction temperature of 37℃and cellulose addition of 0.07 mg.Under the optimal conditions,the yield of total flavonoids from C.tangutorum O.E.Schulz reached 75.90 mg/g.[Conclusions]The optimized extraction process was reasonable and feasible,and it could provide a reference for the extraction of total flavonoids in C.tangutorum O.E.Schulz.This study provided a foundation for the quality control of food/medicinal materials and the development and research of big health products of C.tangutorum O.E.Schulz. 展开更多
关键词 Cardamine tangutorum O.E.Schulz Total flavonoid Response surface methodology Ultrasonic-enzymatic hydrolysis extraction process
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Development of RP-HPLC method for simultaneous determination of docetaxel and curcumin in rat plasma: Validation and stability 被引量:3
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作者 Dong Wuk Kim Abid Mehmood Yousaf +4 位作者 Dong Xun Li Jong Oh Kim Chul Soon Yong Kwan Hyung Cho Han-Gon Choi 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第1期105-113,共9页
The purpose of the present research was to develop a suitable, simple, precise, accurate,robust, and reproducible RP-HPLC method for a reliable simultaneous quantification of docetaxel(DTX) and curcumin(CCM) in rat pl... The purpose of the present research was to develop a suitable, simple, precise, accurate,robust, and reproducible RP-HPLC method for a reliable simultaneous quantification of docetaxel(DTX) and curcumin(CCM) in rat plasma samples using paclitaxel(PTX) as an internal standard. The samples were assayed by the Agilent 1260 Infinity HPLC instrument using a Capcell Pak C8 column(4.6 mm × 150 mm, 5 μm) under isocratic conditions. The mobile phase consisted of acetonitrile and triple distilled water(40/60, v/v) with a flow rate of 1.0 ml/min. The eluent was monitored at 230 nm for simultaneous measurement of curcumin and docetaxel. The method was validated by determining system suitability, selectivity, sensitivity, linearity, inter-day and intra-day precision, accuracy, robustness, and stability in accordance with the guidelines of the United States Food and Drug Administration(FDA).The developed chromatographic method proved to be simple, precise, accurate, robust and reproducible. Moreover, the samples showed stability at room temperature over a period of 48 h. Thus, this method would be employed for routine simultaneous quantification of docetaxel and curcumin in rat plasma samples. 展开更多
关键词 CURCUMIN DOCETAXEL HPLC Plasma-extraction simultaneous determination VALIDATION
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Enhanced Recovery of Resveratrol and Emodin from Polygonum cuspidatum by a Simultaneous Extraction and Acid Hydrolysis Process
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作者 刘芬 李英波 +3 位作者 李敏 李昊剑 梁向峰 刘会洲 《过程工程学报》 CAS CSCD 北大核心 2016年第6期953-959,共7页
A novel and efficient extraction/hydrolysis method was developed for the recovery of resveratrol and emodin from a well-known traditional chinese medicinal herb, Polygonum cuspidatum. By using a 85% aqueous acetone so... A novel and efficient extraction/hydrolysis method was developed for the recovery of resveratrol and emodin from a well-known traditional chinese medicinal herb, Polygonum cuspidatum. By using a 85% aqueous acetone solution containing 1.0 mol/L HCl as extractant, extraction of resveratrol and emodin from P. cuspidatum and conversion of resveratrol-3-O-β-glucoside and emodin-8-O-β-D-glucoside into the products could be achieved in one step. The effects of several key parameters including concentration of HCl and acetone, temperature, ratio of solvent to material, extraction duration and extraction times on the process efficiency was systematically investigated. The results showed that the optimal conditions for maximizing the recovery yield were 85% acetone containing 1.0 mol/L HCl as extractant, temperature 70 ℃, ratio of liquid to solid 50 mL /g and extraction duration 30 min. This one-pot extraction/hydrolysis process increased the yield of resveratrol and emodin to 524% and 302%, respectively, compared to a raw sample without hydrolysis. Compared with conventional method, the developed process not only achieved high yield of resveratrol and emodin, but simplified the procedures and reduced time. The results demonstrated that the simultaneous extraction/hydrolysis process is simple and efficient which could act as a useful approach for enhanced recovery of resveratrol and emodin from P. cuspidatum. 展开更多
关键词 POLYGONUM cuspidatum RESVERATROL EMODIN GLYCOSIDES simultaneous extraction/hydrolysis
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Experimental Research on the Reusing & Recycling Technology of Oil Extraction Wastewater Treatment in Oil Field
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作者 董晓丹 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第1期88-92,共5页
How to use water resource effectively is an important problem in developing industry. Three combined processes which are composed of oil separator+de-emulsification flocculation+sand filtration (SDF), oil separato... How to use water resource effectively is an important problem in developing industry. Three combined processes which are composed of oil separator+de-emulsification flocculation+sand filtration (SDF), oil separator q-hydrolytic acidification+SBR (SAS) and oil separator+de emulsification flocculation +SBR (SDS) are conducted in laboratory-scale experiment to treat oil extraction wastewater for an oil field. The experimental results show that the removal rate of COD(chemistry oxygen demand) and oil treated by SDF process are 85 % and 95 % respectively, the residual oil in effluent can meet the discharge standard, but the residual COD can not. The removal rate of COD and BOD (biological oxygen demand) of the SAS effluent are 85% and 90% respectively, the BOD can meet but the COD can not meet discharge standard. So the further treatment is required in the process. The SDS effluent with removal rate of 95% and 90% are obtained for COD and BOD respectively, which can completely meet the national standards of oil wastewater discharge and refilling (China). The experimental result shows that oil extraction wastewater has turned into water resource after being, treated by SDS. 展开更多
关键词 de-emulsification Ilocculent sand Iiltration SBR. hydrolysis acidification oil extraction wastewater
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Mathematical modeling for of arctigenin from acidultrasonic-assisted extractionhydrolyzed FructusArctii
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作者 Dai Lin Zhang Yong +2 位作者 Hu Chi Qian Hongliang Wang Zhixiang 《Journal of Southeast University(English Edition)》 EI CAS 2017年第3期362-369,共8页
A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid pr... A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid promotes the conversion of arctiin to arctigenin in the arctiin-rich active pharmaceutical ingredient, and the hydrolyzed products were further examined to investigate the process setup. By considering the mechanism of the extraction process and experimental data, the effects of parameters including solven to solid ratio, particle size of hydrolyzed samples, ethano volume fraction, ultrasound power, extraction temperature and extraction time on concentration of arctigenin were analyzed in detail. The model was suitable for simulating the process of ultrasonic-assisted extraction of arctigenin. The simulation results of the model agree well with experimental data with the deviation below13%, indicating that the mathematical mode can provide valuable guidance for the extraction of arctigenin from acid hydrolyzed FructusArctii. 展开更多
关键词 FructusArctii acid hydrolysis ultrasonic-assisted extraction ARCTIGENIN mathematical model
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