下载排行
Comparison of Compression and Distillation Processes for Essential Oils Extraction from Citrus
XIE Lian-wu~(1), GUO Ya-ping~(1),ZHOU Chun-shan~(1), ZHOU Jin-hua~(1,2)(1.School of Chemistry and Chemical Engineering, Central South University, Changsha 410083,China;2. School of Science, Central South Forestry University, Zhuzhou 412006,China )In order to identify a continuous process for essential oils extraction from citrus with the characters of low-cost, low resource-consuming and high efficiency, compression process is used in the essential oils extraction from citrus by compared with distillation process. The study result shows that the recovery of transparent essential oils by distillation process is 1.2%～2.1%, and the smaller granularity and the more additive ammonium chloride, the bigger the recovery. In contrast to this,the recovery of flaxen essential oils by compression process is lower as 1.0%～1.6%, but its odor is as better as close to the fragrance of natural fresh citrus. Therefore, compression process is fit for large-scale continuous citrus essential oils produce.
Progress in Hydrothermal Carbonization of Waste Biomass and Application of Biochar in Wastewater Treatment
LIU Yitao;WEI Jia;LI Jun;Biomass carbonization,which mainly fixes biomass in the form of stable carbon through carbonization to form a new type of biochar products,is an emerging technology in biomass utilization.We briefly introduced the technology of biomass carbonization,and mainly introduced the research progress in biochar prepared by waste biomass with high moisture content,such as agricultural and forestry waste,food waste,livestock and poultry manure,and excess sludge through hydrothermal carbonization.Moreover,we discussed the application of hydrothermal biochar in the the treatment of wastewater containing organics,heavy metals,and anions.Finally,we forecast the prospect of hydrothermal carbonization of biomass.
Research Progress on Electrochemical Oxidation Treatment in Refractory Wastewater
CHENG Di,ZHAO Xin,QIU Feng,ZHOU Lei,LI Chang-bo,ZHANG Hong-lin(School of Environmental and Biological Engineering,Liaoning Shihua University,Fushun 113001,China)This paper describes the research progress of electrochemical oxidation treatment in refractory wastewater at home and abroad,discusses the mechanism of electrochemical oxidation including anodic oxidation technique and cathodic reduction technique in detail,introduces the main influential factors on the degradation efficiency of electrochemical oxidation such as electrode materials,electrochemical reactor,the pH value of the solution,solvent and other factors.The research of electrochemical oxidation mechanism for organic pollutants,the development of electrode materials,the research and development of high efficiency electrolysis reactor,the research on application of specific electrochemical oxidation systems are aspects of the prospect of electrochemical oxidation treatment in refractory wastewater.
Research Progresses of Synthesis of Pharmaceuticals Catalyzed by Lipases
XIONG Xiao-long1,2,DU Peng-fei1,JIN Peng1,2,WANG Qiu-yan1,XIE Tian1(1.Center for Biomedicine and Health,Hangzhou Normal University,Hangzhou 310012,China;2.School of Life and Environmental Science,Hangzhou Normal University,Hangzhou 310036,China)Lipases constitute the most important group of biocatalysts for industrial applications.Being capable of catalyzing diverse reactions under mild conditions with high efficiency,regioselectivity and stereoselectivity,lipases are the most widely used group of biocatalysts in pharmaceutical synthesis.In recent years,much progress had been achieved by researcher on lipase catalyzed pharmaceutical synthesis.For a better understanding of this development,we reviewed recent industrial application concerning the practical use of lipases in synthesis of antiinflammatory drugs,antidepressant drugs,antibacterial drugs,anticancer drugs,vitamin drugs and their intermediates.Selected examples of achievement of optimized lipases and improved reaction conditions in novel synthetic routes were highlighted.
Research Progress in Cellulase Excreted from Biology
LIU Jie-li,WANG Jing (Faculty of Chemical Science and Engineering,China University of Petroleum(Beijing),Beijing 102249,China)Cellulase is the most effective catalyst in degradation of cellulose.In the natural world there are many types of biological production of cellulase.This paper summarizes the cellulase in a variety of categories,clan,structure;cellulase produced by protozoa,epigenetic animals, and microbial strains (such as bacteria,fungi,actinomycetes,etc);cellulase coding genes and their expression;mechanisms of cellulase.Advices on forward research trend and focus are also mentioned.
Research Progress in Hydrogen Production Technologies and Pathways for Large-Scale Application
CUI Weiyi;WANG Yi;YU Yong;XU Jie;YANG Jianli;JIANG Jizhou;Under the background of global energy transition and the "double-carbon" goals, hydrogen energy plays a significant role in China′s energy system.We systematically analyze the advantages and disadvantages of hydrogen production technologies, including traditional fossil fuel-based hydrogen production, industrial by-product hydrogen production, and water electrolysis for hydrogen production.We mainly introduce the research progress of the hydrogen production system from the aspects of key hydrogen production technologies, development directions, and applications.Combined with policy guidance and technological development trends, we put forward that collaborative innovation and large-scale application are the key driving forces for the popularization of hydrogen energy.The review provides rational suggestions for the construction of a low-carbon energy system.
The Main Chemical Constituents and Pharmacological Activities of Cornus Officinalis Sieb.et Zucc
YUAN Ju-li1,JIANG Hong-bo2(1.Shanxi Province Key Laboratory of Phytochemistry,Baoji University of Arts and Sciences,Baoji 721013,China;2.Key Laboratory of Disaster Monitoring and Mechanism Simulating,Baoji University of Arts and Sciences,Baoji 721013,China)Cornus officinalis Sieb.et Zucc,as one of the three most valuable medicinal plants in the world,has antibacterial,immune regulation,lowering blood sugar and blood lipid,antioxidative,anticancer,anti AIDS,cardiac and other important medicinal values.This article focuses on the chemical constituents of Cornus officinalis Sieb.et Zucc and its pharmacological activities.
Research in Synthesis of p-Aminobenzoic Acid
LIU Zhi-xiong, CHENG Qing-rong, LI Xiang (Hubei Research Institute of Chemistry, Wuhan , 430074, China)The progress of research in synthesis of p-aminobenzoic acid from differenrt material is presented. The advantages and disadvantages of various synthesis of methods are discussed economically and technologically. The synthesis of method from p-nitrobenzoic acid is discussed emphatically.
Optimization in Phenol-Sulfuric Acid Method for Determination of Content of Paulowniae flos Polysaccharide by Response Surface Methodology
LV Tingting;YANG Zhihua;HAN Yonghong;MENG Xin;TAO Juan;LIU Xu;We performed the methodology validations for the determination of the content of Paulowniae flos polysaccharide by a phenol-sulfuric acid method.Moreover,we investigated the effects of phenol amount,sulfuric acid amount,water bath temperature,and coloration time on the determination of the content of Paulowniae flos polysaccharide by single-factor experiments,and then further optimized the determination conditions of phenol-sulfuric acid method by response surface methodologies.Furthermore,we determined the content of Paulowniae flos polysaccharide under the optimal conditions.The results show that the linear relationship is good in the range of 0.01-0.08 mg·mL-1(R=0.9993),the adding standard recovery of Paulowniae flos polysaccharide is 98.94%-101.93%,and the RSD is 1.0%-1.4%.The optimal conditions are determined as follows:the phenol amount of 0.4 mL,the sulfuric acid amount of 5.0 mL,and the coloration time of 25 min.Under above conditions,the average content of Paulowniae flos polysaccharide is 2.65%,and the RSD is 2.95%.The optimized method is stable and reliable with good precision and high accuracy,which can be used for the determination of the content of Paulowniae flos polysaccharide.
Optimization in Extraction Process of Flavonoids from Morus alba L. by Response Surface Methodology and Its Antioxidant Activity in vitro
ZHANG Guanghui;LIU Jingli;LONG Xu;ZHANG Lina;Taking 95% ethanol as the solvent, we extracted flavonoids, the active constituents from Morus alba L.by an ultrasonic method.Moreover, taking the extraction rate of flavonoids as an evaluation index, we optimized the extraction process by response surface methodologies on the basis of single-factor experiments, and studied the antioxidant activity of the flavonoids extract.The results show that the optimum extraction conditions can be determined as follows: the extraction temperature of 45.78 ℃,the extraction time of 38.33 min, and the solid-liquid ratio of 1∶25.52(g∶mL).Under above conditions, the extraction rate can reach 2.211%.In vitro antioxidant experiments indicate that the scavenging rate of 4.00 mL 0.05 mg·mL-1 DPPH free radicals is 62.21% by 2.00 mL 0.50 mg·mL-1 flavonoids extract from Morus alba L.,which is lower than that of the positive control VC with the same concentration(81.39%).The precision, stability, and repeatability of antioxidant experiments are good, and RSD values are 0.05%,0.15%,and 0.69%(n=5),respectively.The extraction method is simple, efficient, and reliable, which provides a theoretical basis for the subsequent development of Morus alba L..