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Extraction and Antioxidant Activity Analysis of Crude Polysaccharides from Wild Lactarius volemus Fr. in Yunnan Province 被引量:1
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作者 Meihua XIE Zhongze LUO +2 位作者 Yongtao HU Xiufeng LI Haiyan YANG 《Agricultural Biotechnology》 CAS 2015年第6期53-56,共4页
[ Objective ] This study aimed to investigate the optimal extraction process of crude polysaccharides from wild Lactarius volemus Fr. in Yunnan Province and preliminarily analyzed its antioxidant activity in vitro. [ ... [ Objective ] This study aimed to investigate the optimal extraction process of crude polysaccharides from wild Lactarius volemus Fr. in Yunnan Province and preliminarily analyzed its antioxidant activity in vitro. [ Method ] With water extraction and alcohol precipitation method, the optimal conditions for extracting crude polysaccharides from wild L. volemus Ft. were screened by single-factor and orthogonal experiments. The antioxidant activity of the extracted crude polysac- charides was determined with DPPH assay. [ Result ] The optimal conditions for pigment removal with activated carbon were: activated carbon amount of 20 g/L, water bath time of 40 min, water bath temperature of40 ℃ ; the optimal conditions for extracting crude polysaccharides from wild L. vo/emus Fr. with hot water ex- traction method were: hot water extraction time of 3 h, solid-liquid ratio of 1: 45, extraction frequency of twice. Under the optimized extraction conditions, the yield of crude polysaccharides was 21.33 mg/g. In addition, the antioxidant activity of 0. 665 mg/ml crude polysaccharides was 52.46% ; the amount of crude polysac- eharides was proportional to the antioxidant activity. [ Conclusion] Hot water extraction method can be used as a high-efficiency extraction technology of crude pol- ysaecharides from wild L. volemus Fr. with simple operation and low costs. Crude polysaccharides extracted from L. volemus Ft. exhibited certain antioxidant activi- ty in vitro. 展开更多
关键词 Lactarius volemus Fr. crude polysaccharide Antioxidant activity Extraction method
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Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation 被引量:1
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作者 Jingjing Liang Meina Zhang +6 位作者 Xiaohan Li Yuan Yue Xiaowei Wang Mengzhen Han Tianli Yue Zhouli Wang Zhenpeng Gao 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期421-433,共13页
Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were... Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were extracted from fermented and non-fermented L.edodes and purified via DEAE-52 and Sephadex G-100.The components designated F-LEP-2a and NF-LEP-2a were analyzed by FT-IR,HPGPC,HPAEC,SEM,GC-MS and NMR.The results revealed that probiotic fermentation increased the molecular weight from 1.16×10^(4) Da to 1.87×10^(4) Da and altered the proportions of glucose,galactose and mannose,in which glucose increased from 45.94%to 48.16%.Methylation analysis and NMR spectra indicated that F-LEP-2a and NF-LEP-2a had similar linkage patterns.Furthermore,their immunomodulatory activities were evaluated with immunosuppressive mice.NF-LEP and F-LEP improved immune organ indices,immunoglobulin(Ig G and Ig M)and cytokines concentrations;restored the antioxidation capacity of liver;and maintained the balance of gut microbiota.F-LEP displayed better moderating effects on the spleen index,immunoglobulin,cytokines and the diversity of gut microbiota than NF-LEP(200,400 mg/kg).Our study provides an efficient and environment-friendly way for the structural modification of polysaccharides,which helps to enhance their biological activity and promote their wide application in food,medicine and other fields. 展开更多
关键词 Lentinus edodes polysaccharide Lactobacillus fermentum fermentation Structural analysis Immunoregulatory activity Nuclear magnetic resonance
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Severity Risk Analysis Matrix Ranking (SRAMR) for Oil-Spill Contingency Planning: Asemoku-Agip Pipeline in Perspective
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作者 Ifuwe Chineme Christabel Onosemuode Christopher 《Journal of Geoscience and Environment Protection》 2024年第6期190-206,共17页
One of the down sides of crude oil exploration and exploitation in the developing nations is its impacts on the environment. A major manifestation of poor crude oil management is oil-spillages. Mitigation strategies h... One of the down sides of crude oil exploration and exploitation in the developing nations is its impacts on the environment. A major manifestation of poor crude oil management is oil-spillages. Mitigation strategies have been too expensive, but a cheaper recent way of managing crude-spills is by developing a severity risk analysis matrix ranking (SRAMR). The spatial data-sets deployed in this study were acquired from the USGS, Google Earth Pro, and NOSDRA. A buffer zone of 100 - 400 meters was created to characterize the LULC characteristics of the area. Also, this was to help develop a risk sensitivity characteristic. The study found that the vegetal cover was the environmental resource at high risk to crude-spills in the area, while other land-uses were at low risk of crude-spill. It is hoped that the finding from this study informs policy development and planning for crude oil spill incidents. 展开更多
关键词 Land-Use/Land-Cover Asemoku crude-Spills Severity-Risk-analysis
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Comparative Analysis of Proanthocyanidins and Polysaccharides on Wild Lycium ruthenicum 被引量:1
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作者 Haijun CHEN Jiawei LIU +6 位作者 Yumei SHAN Lijun HE Yong YANG Yan ZHENG Jie HOU Yu ZHOU Lixiao MA 《Medicinal Plant》 CAS 2019年第1期26-30,共5页
[Objectives] To compare content of proanthocyanidins and polysaccharides in wild Lycium ruthenicum. [Methods] The wild L. ruthenicum collected from different regions such as Qinghai, Inner Mongolia, Ningxia and Gansu ... [Objectives] To compare content of proanthocyanidins and polysaccharides in wild Lycium ruthenicum. [Methods] The wild L. ruthenicum collected from different regions such as Qinghai, Inner Mongolia, Ningxia and Gansu Province were taken as the research objects. The conventional indicators such as proanthocyanidins and polysaccharides of the experimental materials were determined, and the proanthocyanidins and polysaccharides of the experimental materials in different regions were compared and analyzed. The difference in content and correlation, and the cluster analysis method were used to divide clusters of the experimental materials. [Results] The absorbance of proanthocyanidins in the fruit of wild L. ruthenicum was No.4>No.1>No.5>No.6>No.3>No.2, among which the absorbance of anthocyanin(2.43) of wild L. ruthenicum variety No.4 was significantly higher than other experimental materials(P<0.05), and proanthocyanidin of No.2 had the lowest absorbance value of 1.35. There was no significant difference between No.3 and No.6(P>0.05), and there were significant differences among other experimental materials(P<0.05). The content of polysaccharides was: No.3>No.7>No.2>No.4>No.5>No.6>No.1; there was no significant difference between No.3 and No.7(P>0.05), but significantly higher than other materials(P<0.05). Besides, proanthocyanidins and polysaccharides showed significant variability, but there was no consistency in the correlation between them. [Conclusions] In terms of the absorbance of proanthocyanidins, the experimental materials No.1 and No.4 can be classified into a cluster; experimental materials No.2, No.3, No.5 and No.6 can be classified into another cluster. This can provide a theoretical basis for the introduction and breeding of fine varieties. 展开更多
关键词 LYCIUM ruthenicum PROANTHOCYANIDINS polysaccharides Variation analysis CLUSTER analysis
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Component Analysis and Free Radicals Scavenging Activity of Physalis alkekengi L. Polysaccharide 被引量:19
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作者 CHENG Ying-kun LI Lei MENG Zhao-kun HOU A-li WU Yu-jie TENG Li-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第2期167-170,共4页
A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed... A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed of rhamnose, xylose, arabinose, galactose, and glucose. Free radicals scavenging activity of PAP was studied through 3 free radicals scavenging tests. PAP exhibited high scavenging effects on OH and DPPH radicals, and both the scavenging rates were about 80%. The scavenging rate of O2^- radical was about 22%. 展开更多
关键词 PHYSALIS polysaccharidE Component analysis Free radicals scavenging activity
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Structural Analysis of Water-soluble Polysaccharide PIP_1 Extracted from the Cultured Mycelium of Phellinus igniarius 被引量:7
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作者 WU Ming-jiang JIANG De-zhi +1 位作者 LIU Tie-mei ZHANG Li-ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第6期708-711,共4页
Water-soluble crude polyseccharide(PIP) was extracted from cultured mycelium of the fungus Phellinus igniarius. After ethanol precipitation and sepharose CL-6B gel filtration, the fraction of PIP1 was obtained, whic... Water-soluble crude polyseccharide(PIP) was extracted from cultured mycelium of the fungus Phellinus igniarius. After ethanol precipitation and sepharose CL-6B gel filtration, the fraction of PIP1 was obtained, which was shown to be a homogeneous polysaccharide by means of high-performance liquid chromatography. The structure of PIPt was determined by using several methods. C.,C analysis indicates that PIP1 is composed of the monosaccharides of glucose, galactose, and mannose. Their malar ratio is 3. 70: 4. 06: 1.00. The molar weight was estimated to be 17 kd via HPLC. IR, GC, partial hydrolysis with acid, pefiedate oxidation, Smith degradation, methylation, and GC-MS analysis were used for the structural analyses of PIP1. The results show that PIP1 has a small quantity of branch structure, The main glycosidic linkage of PIP1 has a β-configurafion. The main chain is made up of a large mass of glucose ( 1→3 ) and few mannose ( 1→4 ) ; the side chain is composed of glucose ( 1 →3 ) and galactose ( 1→6 ) ; the nonreduced end is composed of galactose and glucose. The side chains are branched at 6-0 of glucose( 1→3,6) and mannose(1→4,6). On an average, there are three branches among 20 residues. It is presumable that the existence of 1,3-linked Glc in the main and side chains is the main reason for its higher antitumor activity. 展开更多
关键词 Phellinus igniarus Cultured mycelium polysaccharidE Structural analysis
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The interactions between Chinese local corn and WTI crude oil prices:an empirical analysis 被引量:2
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作者 Zhengwei Ma Wenjia Hou 《Petroleum Science》 SCIE CAS CSCD 2019年第4期929-938,共10页
This paper investigates the relationship between China’s fuel ethanol promotion plan and food security based on the interactions between the crude oil market, the fuel ethanol market and the grain market. Based on th... This paper investigates the relationship between China’s fuel ethanol promotion plan and food security based on the interactions between the crude oil market, the fuel ethanol market and the grain market. Based on the US West Texas Intermediate(WTI) crude oil spot price and Chinese corn prices from January 2008 to May 2018, this paper applies Granger causality testing and a generalized impulse response function to explore the relationship between world crude oil prices and Chinese corn prices. The results show that crude oil prices are not the Granger cause of China’s corn prices, but changes in world crude oil prices will have a long-term positive impact on Chinese corn prices. Therefore, the Chinese government should pay attention to changes in crude oil prices when promoting fuel ethanol. Considering the conduction e ect between fuel ethanol and the food market, the government should also take some measures to ensure food security. 展开更多
关键词 WTI crude oil spot PRICE CHINESE CORN PRICE GRANGER CAUSALITY test Impulse response analysis
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Anticancer Effect of Ginseng Leaves Crude Polysaccharides on Human Hepatoma Cell SMMC-7721 被引量:4
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作者 Xiaozhen Fu Dan Shi +3 位作者 Chao Qu Guangying Zhong Wei Zou Jing Liu 《Chinese Medicine》 2014年第2期87-93,共7页
Background: Polysaccharides extracted from the medicinal herbs are known to possess antitumor effects. Although there is a significant number of evidences implicated on the beneficial effects of the ginseng leaves gin... Background: Polysaccharides extracted from the medicinal herbs are known to possess antitumor effects. Although there is a significant number of evidences implicated on the beneficial effects of the ginseng leaves ginsenoside with diverse associated mechanisms, reports on the anticancer by the ginseng leaves crude polysaccharides (GLCP) are not sufficient. Experiments were carried out to unravel the anticancer effects of GLCP. Methods: Cells were treated with GLCP (0.5 - 2 mg/ml) for 48h. MTT method was used to detect the cell viability. Western blot and flow cytometry were used to detect apoptotic rate. Western blot and acridine orange staining were used to detect the cell autophagy. Results: Compared with the normal human liver cell (Chang liver), GLCP (1.5 - 2 mg/ml) significantly reduction cell viability, promote apoptosis-related proteins expression, promote cell apoptosis and autophagy in SMMC-7721 cells. But caveolin-1 gene silencing could inhibit the anticancer effect of GLCP. Conclusions: These data suggest that GLCP promote autophagy and apoptosis in human hepatoma cell SMMC-7721. We speculate that its mechanism may be associated with the caveolin-1 which is an essential structural molecule of caveolae. Although the effect of GLCP inhibited of liver cancer is not very strong, we are more interested in the GLCP which plays a tumor suppressor role in health care. 展开更多
关键词 ANTICANCER GINSENG LEAVES crude polysaccharides (GLCP) CAVEOLIN-1 Autophagy Apoptosis
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Heat Exchanger Network Retrofit for Optimization of Crude Distillation Unit Using Pinch Analysis 被引量:2
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作者 Sun Mengying Fu Dianliang Sun Lanyi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第1期31-40,共10页
Crude distillation unit(CDU)is regarded as the main energy consumer in the entire refinery process.In this paper,the process simulation software and the energy management software are used to simulate the flowsheet an... Crude distillation unit(CDU)is regarded as the main energy consumer in the entire refinery process.In this paper,the process simulation software and the energy management software are used to simulate the flowsheet and analyze the energy consumption,respectively.Stream data obtained from an existing CDU are applicable in the pinch analysis.To reduce the amount of cross-pinch heat transfer,three approaches of resequencing,repiping,and adding heat exchangers are adopted.Compared with the existing CDU,the results demonstrate that the inlet temperature of the furnace can be increased by 25.4℃,the amount of hot and cold utilities can be reduced by 15.1%and 19.6%,respectively.The economic evaluation indicates that the operating cost is saved by 8×106$/a,and the payback period is about 9 months. 展开更多
关键词 crude distillation unit pinch analysis heat exchanger network RETROFIT energy saving
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Techno-Economic Analysis and Life Cycle Assessment for the Typical Intermediate Crude Refining Scheme in China 被引量:2
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作者 Zhou Xin Yan Hao +4 位作者 Feng Xiang Zhao Hui Liu Yibin Chen Xiaobo Yang Chaohe 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第4期35-45,共11页
The integration of refinery and petrochemical units(IRPUs)has become an inevitable choice for the sustainable development of petrochemical industry.The utilization efficiency of petroleum resources could be improved o... The integration of refinery and petrochemical units(IRPUs)has become an inevitable choice for the sustainable development of petrochemical industry.The utilization efficiency of petroleum resources could be improved obviously through IRPUs.However,integrating economic and environmental impacts into the model of IRPUs is still a grand challenge.Herein,a model called TEA-GHG-OPWM(Techno-Economic Analysis and GreenHouse Gases Oriented Plant-Wide Model)has been established on Aspen HYSYSTM platform to calculate the energy consumption,the technoeconomic performance,and the GHG emissions for two different kinds of schemes,viz,:VRHCU(Vacuum Residue Hydrocracking Unit)and VRDS-RFCC(Vacuum Residue Desulfurization and Residue Fluid Catalytic Cracking).Furthermore,a novel processing pathway named VGOHDT-HTMP-DC(Vacuum Gas Oil Hydrotreating,Hydrogenation and TMP coupling process and Delayed Coking)has also been developed to find methods to improve the economic performance based on a ten-million-CNY output value(TMYOV)and a reduced GHG emissions.Our results demonstrate that VRHCRU could consume more energy and emit more GHG(877.11 t of CO2 eq·TMYOV^-1·h^-1)than VRDS-RFCC(817.03 t of CO2 eq·TMYOV^-1·h^-1)and VGOHDT-HTMP-DC(721.96 t of CO2 eq·TMYOV^-1·h^-1),while obtaining a higher mass yield of petrochemicals.The VGOHDT-HTMP-DC process exhibits the lowest feedstock consumption,hydrogen consumption,energy consumption,and GHG emissions,indicating that VGOHDT-HTMP-DC has both well economic and environmentally friendly performance. 展开更多
关键词 techno-economic analysis life cycle assessment integration of refinery and petrochemical units intermediate base crude oil process simulation
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Near-Infrared Spectroscopy Combined with Absorbance Upper Optimization Partial Least Squares Applied to Rapid Analysis of Polysaccharide for Proprietary Chinese Medicine Oral Solution 被引量:2
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作者 Jiexiong Su Xinkai Gao +5 位作者 Lirong Tan Xianzhao Liu Yueqing Ye Yifang Chen Kaisheng Ma Tao Pan 《American Journal of Analytical Chemistry》 2016年第3期275-281,共7页
Near-infrared (NIR) spectroscopy was applied to reagent-free quantitative analysis of polysaccharide of a brand product of proprietary Chinese medicine (PCM) oral solution samples. A novel method, called absorbance up... Near-infrared (NIR) spectroscopy was applied to reagent-free quantitative analysis of polysaccharide of a brand product of proprietary Chinese medicine (PCM) oral solution samples. A novel method, called absorbance upper optimization partial least squares (AUO-PLS), was proposed and successfully applied to the wavelength selection. Based on varied partitioning of the calibration and prediction sample sets, the parameter optimization was performed to achieve stability. On the basis of the AUO-PLS method, the selected upper bound of appropriate absorbance was 1.53 and the corresponding wavebands combination was 400 - 1880 & 2088 - 2346 nm. With the use of random validation samples excluded from the modeling process, the root-mean-square error and correlation coefficient of prediction for polysaccharide were 27.09 mg·L<sup>-</sup><sup>1</sup> and 0.888, respectively. The results indicate that the NIR prediction values are close to those of the measured values. NIR spectroscopy combined with AUO-PLS method provided a promising tool for quantification of the polysaccharide for PCM oral solution and this technique is rapid and simple when compared with conventional methods. 展开更多
关键词 Near-Infrared Spectroscopic analysis Proprietary Chinese Medicine Oral Solution polysaccharidE Absorbance Upper Optimization Partial Least Squares
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Bioassay-Guided Extraction of Crude Fucose-Containing Sulphated Polysaccharides from Sargassum fusiforme with Response Surface Methodology 被引量:2
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作者 FU Zhifei LI Haihua +4 位作者 LIU Hongbing HU Shuman LI Yueying WANG Mengxue GUAN Huashi 《Journal of Ocean University of China》 SCIE CAS 2016年第3期533-540,共8页
The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composit... The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composite design(CCD) was used with four variables, five levels, and four responses. The four variables were p H value of hydrochloric acid solution, extraction temperature(℃), ratio of liquid to raw material(m L g^(-1)), and extraction time(h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of c FCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the p H value of hydrochloric acid solution was 3.50; the extraction temperature was 100℃; the ratio of liquid to raw material was 15.00 m L g^(-1) and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, c FCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future. 展开更多
关键词 提取工艺 响应面法 岩藻糖 羊栖菜 硫酸多糖 脾细胞增殖 跟踪 中心复合设计
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Correlation Analysis of Quantitative Microscopic Characteristics and Polysaccharide Content of Dendrobium officinale from Guangxi
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作者 Liuyuan FAN Hua ZHU +2 位作者 Jianbei TENG Zhonghua DAI Piaoling HUANG 《Medicinal Plant》 CAS 2022年第4期1-7,11,共8页
[Objectives]The paper was to investigate the correlation between the microscopic characteristic constants and the index component polysaccharide content of Dendrobium officinale from Guangxi.[Methods]The paraffin sect... [Objectives]The paper was to investigate the correlation between the microscopic characteristic constants and the index component polysaccharide content of Dendrobium officinale from Guangxi.[Methods]The paraffin sections of D.officinale were made,and the microscopic characteristic constants of D.officinale stem,including cross section area,vascular bundle area and phloem area,were determined by NIS-Elements D microscopic image processing software.The contents of polysaccharides in D.officinale were determined by UV-Vis spectrophotometry,and the quantitative values of microscopic characteristics of D.officinale with different growth years were analyzed by SPSS 23.0(IBM SPSS Statistics 23.0)data statistical software.The correlation between quantitative microscopic characteristics of D.officinale and its polysaccharide content was analyzed.[Results]According to the correlation between the index component of D.officinale and its quantitative microscopic characteristics,the measurement indexes,the percentage of vascular bundle in the cross section area and the percentage of hard structure in the cross section area,were strongly negatively correlated with polysaccharide content.[Conclusions]The microscopic characteristic constant values of vascular bundles of D.officinale can be used as a method to verify polysaccharide content. 展开更多
关键词 Dendrobium officinale Microscopic characteristics polysaccharides Correlation analysis
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Numerical Study and Economy Analysis of Two Heated Crude Oil Pipelines Laid in One Ditch
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作者 Wenpeng Guo Yongtu Liang 《Energy Engineering》 EI 2022年第5期2049-2064,共16页
In this paper,the transportation economy of two heated crude oil pipelines laid in one ditch is analyzed by taking into account the influence of operating temperature,interval between two pipelines,and distance betwee... In this paper,the transportation economy of two heated crude oil pipelines laid in one ditch is analyzed by taking into account the influence of operating temperature,interval between two pipelines,and distance between two heating stations on the heating energy consumption.To analyze the transportation economy,the two heated crude oil pipelines laid in one ditch are simulated under four operating conditions based on an unstructured finite volume method.Compared with laying two crude oil pipelines separately in two ditches,the results attest notably higher soil temperature,meaning reduced heat dissipation of each pipeline by laying two pipelines in one ditch.It is inferred that for the same desired oil temperature at the inlet of the next heating station,laying two pipelines in one ditch requires lower oil temperature at the outlet of heating station,indicating decreased energy cost at the heating station and improved transportation economy.Then economy analysis of four configurations of laying two pipelines in one ditch is performed.By comparing the results of four conditions,the interval between two pipelines of 1.2 m is found to save the energy most efficiently,which is as large as 26.6%compared with that of laying two pipelines in two separate ditches.In addition,narrowing the pipeline interval and extending the distance between heating stations is beneficial to save heating energy.This study is expected to provide valuable guidance for operation optimization of heated crude oil pipelines. 展开更多
关键词 Heated crude oil pipeline laying two pipelines in one ditch numerical simulation thermal effect economy analysis
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Cross-correlation analysis of crude oil and new energy markets: A new perspective based on carbon emission market 被引量:1
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作者 FENG You-shuai LING Mei-jun 《Ecological Economy》 2019年第1期2-18,共17页
Taking the return series of the EU carbon allowance price, WTI crude oil price, the European renewable energy index and Shenzhen carbon emission price, Daqing crude oil price, the China securities new energy index as ... Taking the return series of the EU carbon allowance price, WTI crude oil price, the European renewable energy index and Shenzhen carbon emission price, Daqing crude oil price, the China securities new energy index as sample data, the multifractal detrend cross-correlation analysis method(MF-DCCA)is used to research the dynamic cross-correlation relationships among the carbon emission market, crude oil market and the new energy market in Europe and China and the source of the multifractality. The empirical analysis shows that the cross-correlations among the carbon emission market, crude oil market and new energy market in Europe and China have all significant multifractal characteristics. Moreover, the multifractal strength of cross-correlation between the carbon emission market and crude oil market is less than that between the carbon emission market and new energy market in Europe. The Chinese market is the opposite. In addition, the multifractal strength of cross-correlation between the crude oil market and new energy market in Europe is more than that between the crude oil market and new energy market in China. It is also found that the long-range correlation of the sequences themselves and the fat-tailed distribution in fluctuations are the common causes of the multifractality, and the fat-tailed in fluctuations distribution contributes more to the multifractals of the series. 展开更多
关键词 carbon emission MARKET NEW energy MARKET CROSS-CORRELATION MULTIFRACTAL statistical analysis
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Crude Polysaccharide and Triterpene Content of Ganoderma Fruit Bodies at Different Stages of Development 被引量:1
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作者 FU Lizhong WU Xueqian +5 位作者 LI Mingyan LI Haibo WEI Hailong WU Qingqi CHENG Junwen HE Liang 《食用菌学报》 2008年第3期51-54,共4页
Crude polysaccharide and triterpene levels were determined in the fruit bodies of eleven Lingzhi samples,designated as Ganoderma lucidum,G.capense and G.tsugae,harvested at four different stages of development: buddin... Crude polysaccharide and triterpene levels were determined in the fruit bodies of eleven Lingzhi samples,designated as Ganoderma lucidum,G.capense and G.tsugae,harvested at four different stages of development: budding,elongation,maturation and senescence.In most cases,crude polysaccharide levels were highest at the budding stage,decreased during the elongation stage,increased again at maturation and were lowest at senescence.Triterpene levels generally remained relatively high during the first three developmental stages but were markedly lower at senescence. 展开更多
关键词 粗多糖 三萜 灵芝 植物
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Retrofit of the Heat Recovery System of a Petroleum Refinery Using Pinch Analysis
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作者 John M. Joe Ademola M. Rabiu 《Journal of Power and Energy Engineering》 2013年第5期47-52,共6页
Energy efficiency has become an important feature in the design of process plants with the rising cost of energy and the more stringent environmental regulations being implemented worldwide. In South Africa, as elsewh... Energy efficiency has become an important feature in the design of process plants with the rising cost of energy and the more stringent environmental regulations being implemented worldwide. In South Africa, as elsewhere, most process plants built during the era of cheap energy place little emphasis on the need for energy recovery due to the abundance of cheap utilities sources such as coal. In most of these plants, there exist significant potential for substantial process heat recovery by conceptual design of the heat recovery system. By maximizing heat recovery from the processes, there will be a reduction in the process utilities requirement and the associated environmental effects. Pinch analysis has been demonstrated to be a simple but very effective tool for heat integration and optimization of chemical plants. This study uses the pinch principle to retrofit the heat exchanger networks (HEN) of the crude distillation unit of an integrated petroleum refinery to evolve a HEN that features optimum energy recovery. The network was further relaxed by trading off energy cost with capital cost to obtain an optimal HEN topology not too different from the existing network. The simulation works were implemented in AspenPlus v8.0 environment. Analysis revealed that 34 per cent saving on energy usage per annum is realizable. This significant saving in energy also results in diminished gaseous pollutants associated with energy usage. 展开更多
关键词 Plant RETROFIT HEAT Integration crude Distillation Unit HEAT EXCHANGER Network PINCH analysis Optimization REMAINING Problem analysis
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A heteropolysaccharide from Rhodiola rosea L.:preparation,purification and anti-tumor activities in H22-bearing mice
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作者 Yaru Wu Qing Wang +3 位作者 Huiping Liu Lulu Niu Mengyu Li Qi Jia 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期536-545,共10页
Numerous polysaccharides isolated from plants have been used to augment traditional drugs in the treatment of cancer.In order to explore the influence to hepatocellular carcinoma,a novel cold water-soluble polysacchar... Numerous polysaccharides isolated from plants have been used to augment traditional drugs in the treatment of cancer.In order to explore the influence to hepatocellular carcinoma,a novel cold water-soluble polysaccharide was separated from Rhodiola rosea L.root(RLP)and then its structure and anti-cancer activities were tested.The chemical compositions and high performance gel permeation chromatography(HPGPC)results indicated that RLP was an acid heteropolysaccharide with the molecular weight of about1.15×10~6 Da.Furthermore,ion chromatography(IC),Fourier transform infrared(FT-IR)and nuclear magnetic resoance(NMR)further indicated that RLP was main composed of→2,4)-α-Rha(1→,→5)-α-L-Araf-(1→,α-D-Glu,→6)-β-D-Galp-(1→,β-D-Man and→4)-α-GalpA-(1→.In vivo antitumor activities of RLP were carried out by using H22 tumor-bearing mice model.The results shown that RLP(100 and 300 mg/kg)could inhibit tumor growth of H22 cells from 23.59%to 45.52%and protect thymuses and spleen without damage.In addition,according to cell cycle,AV-FITC/PI and JC-1,RLP could induce dose-dependent apopto sis of H22 cells via S phase arrested which was through a mitochondrial related pathway.Our data indicated that RLP has a broader application prospect in anti-tumor preparations. 展开更多
关键词 polysaccharidE Antitumor activity Rhodiola rosea L. Structure analysis
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鲍鱼脏器碱提多糖的分离纯化、结构表征及抗氧化活性研究 被引量:1
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作者 林志超 潘晓明 +3 位作者 吴启赐 薛钰 黄家福 潘裕添 《食品工业科技》 CAS 北大核心 2024年第4期53-60,共8页
目的:分离纯化鲍鱼脏器碱提多糖(alkali-extracted abalone vscera polysaccharides,Aavp),并研究其结构和抗氧化活性,以期为鲍鱼脏器碱提多糖的开发及应用提供参考。方法:通过热碱提醇沉获得鲍鱼脏器碱提粗多糖,经DEAE Sepharose Fast ... 目的:分离纯化鲍鱼脏器碱提多糖(alkali-extracted abalone vscera polysaccharides,Aavp),并研究其结构和抗氧化活性,以期为鲍鱼脏器碱提多糖的开发及应用提供参考。方法:通过热碱提醇沉获得鲍鱼脏器碱提粗多糖,经DEAE Sepharose Fast Flow和Sephacryl S-400 HR纯化得到高纯度多糖,并利用气相色谱、高效液相色谱、红外光谱和热重分析仪等工具分析其结构及抗氧化活性。结果:粗多糖纯化后得到四个组分,包括Aavp Ia、Aavp Ib、Aavp IIa和Aavp IIb,其中Aavp IIa得率较高,选择其进一步进行结构分析。分析发现,Aavp IIa由木糖和半乳糖组成,分子量为166513 Da;糖苷键构型为α型,组成如下:半乳糖1→4糖苷键摩尔百分比为11.81%,半乳糖1→3糖苷键为34.14%,半乳糖1→2糖苷键为10.14%;木糖1→3糖苷键摩尔百分比为33.85%,1→2和1→4糖苷键共占10.06%。热重分析显示,Aavp IIa在226.4-332.6℃下断裂分解,热失重率为43.65%。抗氧化实验显示Aavp IIa对O2-·的清除率为85.89%,对DPPH·的清除率为62.17%,具有一定的抗氧化活性。结论:提取的鲍鱼脏器碱提多糖是一类杂多糖,并具有一定的抗氧化活性。 展开更多
关键词 鲍鱼脏器 碱提多糖 单糖组成 热重分析 抗氧化活性
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2024年国际原油价格分析与趋势预测 被引量:2
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作者 赵鲁涛 顾启宇 +2 位作者 曲直 邱瑞祥 丘俊元 《北京理工大学学报(社会科学版)》 北大核心 2024年第2期55-58,共4页
2023年,全球经济增速放缓,在加息、减产、冲突等各因素叠加影响下,全年油价跌宕起伏,回吐2022年的风险溢价。展望2023年,从基本面和非基本面着手,分析全球经济、能源转型、供应、库存、美元、市场投机、黄金和地缘政治等因素未来动向,... 2023年,全球经济增速放缓,在加息、减产、冲突等各因素叠加影响下,全年油价跌宕起伏,回吐2022年的风险溢价。展望2023年,从基本面和非基本面着手,分析全球经济、能源转型、供应、库存、美元、市场投机、黄金和地缘政治等因素未来动向,结合预测模型客观计算和专家的主观判断,对2024年国际原油价格走势进行整体展望和预测。预计2024年国际原油价格进一步下移,国际原油市场供需偏宽松,原油投资者信心不足,地缘冲突、极端天气等事件频发,非基本面扰动因素在短期内放大油价震荡区间,Brent、WTI原油均价将在73~83美元/桶和68~78美元/桶。 展开更多
关键词 原油价格 价格预测 市场分析 全球经济 地缘政治冲突
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