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Automated Extraction for Water Bodies Using New Water Index from Landsat 8 OLI Images 被引量:4
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作者 Pu YAN Yue FANG +2 位作者 Jie CHEN Gang WANG Qingwei TANG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期59-75,共17页
The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to... The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to highlight water bodies in remote sensing images.We employ a new water index and digital image processing technology to extract water bodies automatically and accurately from Landsat 8 OLI images.Firstly,we preprocess Landsat 8 OLI images with radiometric calibration and atmospheric correction.Subsequently,we apply KT transformation,LBV transformation,AWEI nsh,and HIS transformation to the preprocessed image to calculate a new water index.Then,we perform linear feature enhancement and improve the local adaptive threshold segmentation method to extract small water bodies accurately.Meanwhile,we employ morphological enhancement and improve the local adaptive threshold segmentation method to extract large water bodies.Finally,we combine small and large water bodies to get complete water bodies.Compared with other traditional methods,our method has apparent advantages in water extraction,particularly in the extraction of small water bodies. 展开更多
关键词 water bodies extraction Landsat 8 OLI images water index improved local adaptive threshold segmentation linear feature enhancement
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Allelopathic Effects of Water Extracts of Sweet Potato (Ipomoea batatas) on Seed Germination of Ageratum conyzoides 被引量:1
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作者 Shuangshuang Zhang Wenlei Cheng +2 位作者 Ye Chen Mingxing Jiang Genshen Yin 《Journal of Agricultural Chemistry and Environment》 CAS 2023年第2期124-133,共10页
Sustainable weed management strategies are essential to reduce chemical and labor inputs. This study aimed to evaluate the effect of water extracts from sweet potato [Ipomoea batatas (L.) Lamarck] on seed germination ... Sustainable weed management strategies are essential to reduce chemical and labor inputs. This study aimed to evaluate the effect of water extracts from sweet potato [Ipomoea batatas (L.) Lamarck] on seed germination of Ageratum conyzoides L. under controlled conditions. The aqueous was produced from plant parts i.e., roots, stems, and leaves of sweet potato at concentrations of 0.025, 0.050, 0.075, and 0.100 g·mL<sup>-1</sup>. The results showed that the plant parts of sweet potato all contained allelopathic substances, which showed high-concentration inhibition and low-concentration promotion of seed germination of A. conyzoides. When the aqueous extract concentrations were 0.050, 0.075, and 0.100 g·mL<sup>-1</sup>, the germination of A. conyzoides seeds was inhibited, while the germination was promoted at a concentration of 0.025 g·mL<sup>-1</sup>. This shows that when the planting density of sweet potato is large, it can form an obvious prevention and control effect on A. conyzoides, and thus improve herbicide resistance management. 展开更多
关键词 Sweet Potato geratum conyzoides water extracts Allelopathic Effect
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Extracting water body data based on SDWI and threshold segmentation:A case study in permafrost area surrounding Salt Lake in Hoh Xil,Qinghai-Tibet Plateau,China 被引量:1
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作者 QingSong Du GuoYu Li +4 位作者 Dun Chen ShunShun Qi Yu Zhou Fei Wang YaPeng Cao 《Research in Cold and Arid Regions》 CSCD 2023年第4期202-209,共8页
There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources ... There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources in sur-rounding areas and downstream areas,resulting in environmental impact and bringing potential flood disasters,which will induce more serious issues and problems in alpine and high-altitude areas with a fragile habitat(such as the QTP in China).Generally,effective,reasonable,and scientific monitoring of large-scale water bodies can not only document the changes in water bodies intuitively,but also provide important theoretical reference for subsequent environmental impact prediction,and disaster prevention and mitigation in due course of time.The large-scale water extraction technology derived from the optical remote sensing(RS)image is seriously affected by clouds,bringing about large differences among the extracted water result products.Synthetic aperture radar(SAR)RS technology has the unique advantage characteristics of all-weather,all-day,strong penetration,and not being affected by clouds,which is hopeful in extracting water body data,especially for days with cloudy weather.The data extraction of large-scale water bodies based on SAR images can effectively avoid the errors caused by clouds that become prevalent at present.In this paper,the Hoh Xil Salt Lake on the QTP and its surrounding five lakes are taken as the research objects.The 2-scene Sentinel-1 SAR image data covering the whole area on 22 August 2022 was used to verify the feasibility of extracting water body data in permafrost zones.Furthermore,on 22 August 2022,the wealth here was cloudy,which made the optical RS images,e.g.,Sentinel-2 images full of clouds.The results show that:using the Sentinel-1 image and threshold segmentation method to extract water body data is efficient and effective with excellent results in permafrost areas.Concretely,the Sentinel-1 dual-polarized water index(SDWI),calculated by combining dual vertical–vertical(VV)polarized and verti-cal–horizontal(VH)polarized data is a useful index for water extraction and the result is better than each of the VV or VH polarized images. 展开更多
关键词 Permafrost region water body extraction Salt Lake in Hoh Xil Qinghai-Tibet Plateau Sentinel-1 Ecological environment impact Disaster prevention and mitigation
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Water Extract of Rice False Smut Balls Activates Nrf2/HO-1 and Apoptosis Pathways,Causing Liver Injury
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作者 ZHANG Guomei LI Han +4 位作者 LIU Shanshan ZHOU Xuming LU Mingyang TANG Liang SUN Lihua 《Rice science》 SCIE CSCD 2023年第5期473-485,I0025-I0028,共17页
Ustiloxins are vital cyclopeptide mycotoxins originally isolated from rice false smut balls that form in rice spikelets infected by the fungal pathogen Ustilaginoidea virens.The toxicity of the water extract of rice f... Ustiloxins are vital cyclopeptide mycotoxins originally isolated from rice false smut balls that form in rice spikelets infected by the fungal pathogen Ustilaginoidea virens.The toxicity of the water extract of rice false smut balls(RBWE) remains to be investigated.Studies have shown that RBWE may be toxic to animals,but toxicological evidence is still lacking.In this study,we found that the IC50 values of RBWE to BNL CL.2 cells at 24 and 48 h were 40.02 and 30.11 μg/m L,respectively,with positive correlations with dose toxicity and time toxicity.After treatment with RBWE,the number of BNL CL.2 cells decreased significantly,and the morphology of BNL CL.2 cells showed atrophy and wall detachment.RBWE induced DNA presynthesis phase arrest of BNL CL.2 cells,increased the proportion of apoptotic cells and inhibited cell proliferation.RBWE up-regulated reactive oxygen species(ROS) levels and lowered mitochondrial membrane potentials.Additionally,Western blot and q RT-PCR results suggested that RBWE exerted the above effects by promoting the Nrf2/HO-1 and caspase-induced apoptosis pathways in vitro and in vivo.The contents of alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,and total bile acids in the serum of mice from Institute of Cancer were significantly up-regulated by RBWE.At the same time,RBWE can lead to increases in ROS and malondialdehyde contents,decreases in contents of oxidized glutathione,glutathione and reduced glutathione,as well as decrease in catalase and superoxide dismutase activities in mouse liver tissues,demonstrating that oxidative stress occurred in mice.Moreover,liver damage was further detected by haematoxylin-eosin staining and electron microscopy to verify the damage to the mice caused by RBWE.In general,RBWE may cause hepatotoxicity in vivo and in vitro via the apoptosis pathway,which provides a reference for hepatotoxicity and its mechanism of action. 展开更多
关键词 water extract rice false smut ball ustiloxin liver injury Nrf2/HO-1 pathway apoptosis pathway
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Inhibitory Effects of Propolis Water Extract on the Proliferation of Cervical Cancer Cells
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作者 Wenbin XU Yimeng GAO +4 位作者 Nailong LIANG Ling ZHANG Shuang XING Wensong HAO Shaocong LI 《Medicinal Plant》 CAS 2023年第2期57-62,共6页
[Objectives]To investigate the effects of propolis extract on HeLa cells to provide theoretical guidance for facilitating clinical treatment.[Methods]The effects of propolis on inflammation,and proliferation were anal... [Objectives]To investigate the effects of propolis extract on HeLa cells to provide theoretical guidance for facilitating clinical treatment.[Methods]The effects of propolis on inflammation,and proliferation were analyzed based on the levels of DNA transcriptional regulation and mRNA and protein expression levels.[Results]Propolis water extract(PWE)could inhibit the cell proliferation and production of DNA damage in a dosedependent manner.Moreover,the propolis water extract could significantly downregulate the expression of iNOS-Luc,PTGS-2-Luc,and IL-8-Luc,and that it was related to the expression of the NF-κB family protein.After the induction of HeLa cells by propolis,the expression of the cell cycle inhibitor gene p21 was increased,while that of the cell proliferation gene Ki67 was decreased.[Conclusions]Propolis water extract could significantly inhibit the cell proliferation and production of DNA damage,suggesting propolis as a potential candidate for the development of adjunctive therapy against cervical cancer. 展开更多
关键词 Cervical cancer Propolis water extract(PWE) Antineoplastic agents Cell proliferation INFLAMMATION
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Innovative Technologies for Large-Scale Water Production in Arid Regions: Strategies for Sustainable Development
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第7期2506-2558,共53页
Water scarcity in arid regions poses significant challenges to sustainable development and human well-being. This article explores both existing and innovative technologies and methods to produce large amounts of wate... Water scarcity in arid regions poses significant challenges to sustainable development and human well-being. This article explores both existing and innovative technologies and methods to produce large amounts of water to address these challenges effectively. Key approaches include atmospheric water generation, advanced desalination techniques, innovative water collection methods such as fog nets and dew harvesting, geothermal water extraction, and water recycling and reuse. Each method is evaluated for its feasibility with existing technology, potential time of implementation, required investments, and specific challenges. By leveraging these technologies and combining them into a multifaceted water management strategy, it is possible to enhance water security, support agricultural and industrial activities, and improve living conditions in arid regions. Collaborative efforts between governments, private sector entities, and research institutions are crucial to advancing these technologies and ensuring their sustainable implementation. The article provides a comprehensive overview of the current state of these technologies, their potential for large-scale application, and recommendations for future research and development. 展开更多
关键词 Atmospheric water Generation Advanced Desalination Sustainable Development Geothermal water extraction water Recycling Arid Regions water Security
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Anti-tumor Effect and Protective Effect on Chemotherapeutic Damage of Water Soluble Extracts from Hedyotis diffusa 被引量:24
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作者 李瑞 赵浩如 林以宁 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第2期54-58,共5页
Bai-Hua-She-She-Cao Hedyotis diffusa Willd. (Ru-biaceae) is a medicinal herbwidely distributed in northeast Asian countries. In traditional Chinese medicine, it has the effectof 'clearing away heat and toxic mater... Bai-Hua-She-She-Cao Hedyotis diffusa Willd. (Ru-biaceae) is a medicinal herbwidely distributed in northeast Asian countries. In traditional Chinese medicine, it has the effectof 'clearing away heat and toxic material, promoting blood circulation and removing blood stasis'.It is a well known Chinese folk-medicine used for the treatment of appendicitis, sore throat, mumps,acne, sebo-rheic dermatitis and various kinds of tumors, such as tumors of digestive tract,carcinoma of liver. It was reported that the MeOH extract of H. diffusa demonstrated a significantantitumor activity and ursolic acid succeeded in being isolated from the MeOH extract as an activecomponent . Shan BN, et al suggested that the direct aqueous extract of H. diffusa hadimmuno-modulating activity and antitumor activity in vitro through stimulating the immune system tokill or engulf tumor cells. But regarding anti-tumor activity in vivo of water soluble extracts fromH. diffusa, no detail was reported. Therefore, we prepared water soluble extracts (H_1 and H_2)from H. diffusa and evaluated their anti-tumor property in vivo experiments as well as protectiveeffect on chemo-therapeutic damage. 展开更多
关键词 hedyotis diffusa water soluble extracts ANTI-TUMOR CHEMOTHERAPY
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Study on Processing of Clear Banana Juice Using Hot Water Extraction Method 被引量:2
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作者 郑欣 余元善 +4 位作者 吴继军 徐玉娟 肖更生 黄婉华 温靖 《Agricultural Science & Technology》 CAS 2014年第11期2003-2005,2044,共4页
In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat ... In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat treatment might induce the pectin and protein in banana pulp to form insoluble products. The results showed the hot water temperature had a significant effect on the formation of insol-uble polymers in banana pulp from pectin and protein. In 75 ℃ water, the pectin and protein in banana pulp were most inclined to form insoluble products. Under this condition, the clarity of banana juice was also highest. The light transmittance at 660 nm was close to 90%. In the banana juice, extracted by 75 ℃ water, the pectin and protein contents were lowest, and they were lower than 7.3 mg/100 ml and 12.9 mg/100 ml respectively. The 75 ℃ water could not inactivate completely the pectin in banana pulp due to its high heat resistance, Therefore, 0.05% L-cys-teine or ascorbic acid needed to be added into banana pulp to inhibit the browning of juice induced by residual PPO. 展开更多
关键词 Clear banana juice Hot water extraction Polyphenol oxidase Pectin Protein
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Toxicity Effects of Water Extract of Euphorbia fischeriana Steud.against Silkworm(Bombyx mori)
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作者 侯伟倬 甄占萱 +3 位作者 李云祥 杨贵明 李季生 李娜 《Plant Diseases and Pests》 CAS 2011年第1期64-66,共3页
[Objective] Taking silkworm (Bombyx mori) as the test material, the research aimed to study the toxicity effects of Euphorbiafischeriana Steud. against the insects in Lepidoptera. [ Methods ] Water extract was prepa... [Objective] Taking silkworm (Bombyx mori) as the test material, the research aimed to study the toxicity effects of Euphorbiafischeriana Steud. against the insects in Lepidoptera. [ Methods ] Water extract was prepared with fresh perennial E. fischer/ana Steud. , which was applied in silkworm with different methods including daubing the extract on silkworm back, soaking silkworm in the extract and feeding silkworm with the mulberry leaves daubed by the extract. [ Re- suits] Those silkworms whose backs were daubed with the water extract had no obvious poisoning symptom. The silkworms soaked for 1 and 3 min could be survived for about 7 d; the silkworms soaked for 5 min could be survived for about 2 d; and the silkworms soaked for 15 rain could be survived for 10 h at most. Those silk- worms fed with mulberry leaves daubed by water extract completely died after 2 d. [ Conduslons ] The water extract of E. fischer/ana Steud. had significant contact toxicity and stomach poisoning against silkworm. 展开更多
关键词 Euphorbiafischeriana Steud. water extract SILKWORM Contact toxicity Stomach poisoning
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Effect of Temperature, pH and Salt on Fluorescent Quality of Water Extractable Organic Matter in Black Soil 被引量:9
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作者 LI Ming-tang ZHAO Lan-po ZHANG Jin-jing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第7期1251-1257,共7页
Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction tempera... Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction temperature, pH value, and salt on the water extractable organic matter (WEOM) was determined by means of the UV absorbance, fluorescence excitation-emission matrix, and derived fluorescence indexes. In general, the carbon content and aromaticity of WEOM increased with the increasing of extraction temperature, with the exception that there was no significant difference in the amount at 0 and 20℃. More fluorophores, especially microbially-derived organic matter were extracted at high temperature. The pH values of extractant, including 5, 7, and 10, showed no effect on the carbon amount of WEOM, whereas the aromaticity and microbially-derived component gradually increased with the increasing of pH values. The fluorescence intensity of humic acid-like fluorophore was stronger in neutral and alkali condition than that in acidic condition. The addition of 10 mmol L-1 CaCl2 significantly decreased the carbon amount of recovered WEOM. Moreover, it significantly decreased the aromaticity of WEOM and the quantity of fulvic acid-like and humic acid-like fluorophores, whereas increased the percentage of tyrosine-like and tryptophan-like fluorophores in the total fluorophores and the amount of microbially-derived organic matter. Generally, 10 mmol L-1 KCl showed the same influence trend, but with low influence degree. 展开更多
关键词 black soil water extractable organic matter soil profile fluorescence spectroscopy
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Biodegradability of soil water soluble organic carbon extracted from seven different soils 被引量:7
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作者 SCAGLIA Barbara ADANI Fabrizio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期641-646,共6页
Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WS... Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water (soil/water ratio of 1:2, W/V) for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility. 展开更多
关键词 biodegradability test cumulated oxygen uptake water extractable organic carbon water soluble organic carbon
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Proposed Models for Subcritical Water Extraction of Essential Oils 被引量:9
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作者 M.Khajenoori A.Haghighi Asl F.Hormozi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期359-365,共7页
Mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to ... Mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to deter-mine whether the extractions were limited primarily by the near equilibrium partitioning of the analyte between the matrix and solvent (i.e. partitioning thermodynamics) or by the rates of analyte desorption from the matrix (i.e. ki-netics). Four simple models have been applied to describe the extraction profiles obtained with SW: (1) a model based solely on the thermodynamic distribution coefficient KD, which assumes that analyte desorption from the ma-trix is rapid compared to elution; (2) one-site kinetic model, which assumes that the extraction rate is limited by the analyte desorption rate from the matrix, and is not limited by the thermodynamic (KD) partitioning that occurs dur-ing elution; (3) two-site kinetic model and (4) external mass transfer resistance model. For SW extraction, the thermodynamic elution of analytes from the matrix was the prevailing mechanism as evidenced by the fact that ex-traction rates increased proportionally with the SW flow rate. This was also confirmed by the fact that simple re-moval calculations based on determined KD (for major essential oil compounds) gave good fits to experimental data for flow rates from 1 to 4 ml·min-1. The results suggested that the overall extraction mechanism was influenced by solute partitioning equilibrium with external mass transfer through liquid film. 展开更多
关键词 essential oils Zataria multiflora Boiss. subcrltlcal water extraction mechanisn
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Effect of water extracts of larch on growth of Manchurian walnut seedlings 被引量:9
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作者 YANG Li-xue 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期285-288,共4页
A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings... A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings and the allelopathy between the two tree species. Four concentrations (100 g. kg i, 50 g. kg^-1, 25 g. kg^-1 and 12.5 g. kg^-1) were prepared for each kind of extracts. Result showed that the water extracts with low and moderate concentrations accelerated the growth of collar diameter and increased biomass and root/shoot ratio of walnut seedlings. The water extracts from branches and barks with low and moderate concentrations accelerated the height growth of the seedlings, while those from leaves and roots slightly decreased the height growth of seedlings. The fact that application of water extracts of larch improved the growth of Manchurian walnut attributes possibly to the allelopathy between the two tree species. 展开更多
关键词 Juglans mandshurica Larix gmelini water extract Collar diameter Tree height Root/shoot ratio ALLELOPATHY
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Inhibitory Effects of Ginseng Water Extract on Hydroxyl Radical 被引量:3
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作者 Hongyan LI Ruihai LI +1 位作者 Lin ZHAO Yang CAO 《Medicinal Plant》 CAS 2018年第4期107-109,118,共4页
[Objectives] The aim of this work was to compare the inhibitory effects of different water-soluble extracts of ginseng on hydroxyl radical. [Methods]The water-soluble effective parts of ginseng were extracted by ortho... [Objectives] The aim of this work was to compare the inhibitory effects of different water-soluble extracts of ginseng on hydroxyl radical. [Methods]The water-soluble effective parts of ginseng were extracted by orthogonal test,the hydroxyl radical scavenging rate of each extract was determined by salicylic acid method,and the extraction process of the optimum hydroxyl radical inhibitor was optimized using variance analysis and cluster analysis. [Results] A total of 16 samples were prepared. Among them,the sample No. 12 had the highest hydroxyl radical scavenging rate,and the inhibition rate reached 105. 08% at the concentration of 1 g/L. [Conclusions] Ginseng water extract contained hydroxyl radical scavenger,of which the optimum extraction process was as follows: p H of 8,solid to liquid ratio of 1∶ 10,extraction temperature of 4℃,extraction time of 12 h and extraction times of 3. 展开更多
关键词 Ginseng water extract Orthogonal text Hydroxyl radical ANTIOXIDATION
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Determination of volatile organic compounds in river water by solid phase extraction and gas chromatography 被引量:4
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作者 M.A.Mottaleb M.Z.Abedin M.S.Islam 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期497-501,共5页
A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile ... A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD. 展开更多
关键词 solid phase extraction river water environmental analysis VOC recoveries
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XPS analysis and combustibility of residues from two coals extraction with sub-and supercritical water 被引量:7
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作者 WU Bo HU Hao-quan ZHAO Yun-peng JIN Li-jun FANG Yun-ming 《燃料化学学报》 EI CAS CSCD 北大核心 2009年第4期385-392,共8页
Two kinds of residues,obtained from extraction of one weakly reductive coal,Shenfu-Dongsheng coal(SD),and one reductive coal,Pingshuo coal(PS),with sub-and supercritical water on a semi-continuous apparatus,were chara... Two kinds of residues,obtained from extraction of one weakly reductive coal,Shenfu-Dongsheng coal(SD),and one reductive coal,Pingshuo coal(PS),with sub-and supercritical water on a semi-continuous apparatus,were characterized by calorific value analysis and XPS analysis,and the combustion behaviors of residues were investigated by thermogravimetric analysis.The results show that the residues have higher calorific value than raw coal samples,and SD residue has higher calorific value than PS residue.C-C,C-O and pyridinic nitrogen,pyrrolic nitrogen are the dominant form of C,O and N on the surface of raw coal samples and their extraction residues.The combustion behaviors of extraction residues show that the SD residue is more reactive and more easily burned than PS residue. 展开更多
关键词 燃烧性 可燃性 煤加工 SD
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Profile distribution and seasonal dynamics of water-extractable carbohydrate in soils under mixed broad-leaved Korean pine forest on Changbai Mountain 被引量:7
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作者 ZHAO Shan-shan SUN Jin-bing CUI Xiao-yang 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第3期509-514,共6页
Carbohydrate represents an important part of the soil labile organic carbon pool. Water soluble carbohydrate drives the C cycle in forest soil by affecting microbial activity and hot water extractable car- bohydrate i... Carbohydrate represents an important part of the soil labile organic carbon pool. Water soluble carbohydrate drives the C cycle in forest soil by affecting microbial activity and hot water extractable car- bohydrate is thought related to soil carbon sequestration due to the asso- ciation with soil aggregation. In a temperate forest region of northeast China, Changbai Mountain, we investigated the abundance, spatial dis- tribution, and seasonal dynamics of cool and hot-water extractable car- bohydrate in soils under mixed broad-leaved Korean pine forest. The concentrations of cool-water extractable carbohydrate (CWECH) in three soil layers (0-5, 5-10, 10-20 cm) ranged from 4.1 to 193.3 g.kg-1 dry soil, decreasing rapidly with soil depth. On an annual average, the CWECH concentrations in soils at depths of 5-10 and 10-20 cm were 54.2% and 24.0%, respectively, of that in the 0-5 cm soil layer. CWECH showed distinct seasonal dynamics with the highest concentrations in early spring, lowest in summer, and increasing concentrations in autumn. Hot-water extractable carbohydrate (HWECH) concentrations in three soil layers ranged from 121.4 to 2026.2 g.kgq dry soil, which were about one order of magnitude higher than CWECH. The abundance of HWECH was even more profile-dependent than CWECH, and decreased more rapidly with soil depth. On an annual average, the HWECH concentration in soils 10-20 cm deep was about one order of magnitude lower than that in the top 0-5 cm soil. The seasonality of HWECH roughly tracked that of CWECH but with seasonal fluctuations of smaller amplitude. The car- bohydrate concentrations in cool/hot water extracts of soil were positively correlated with UV254 and UV2s0 of the same solution, which has implications for predicting the leaching loss of water soluble organic carbon. 展开更多
关键词 forest soil cool-water extractable carbohydrate hot-waterextractable carbohydrate profile distribution seasonal dynamics
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A Comparative Study of Flavonoid Water-Ethanol Extraction Process in Planted Trollius Chinensis 被引量:1
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作者 Yongfeng Liang 《International Journal of Technology Management》 2014年第8期167-170,共4页
With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogona... With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogonal experiment, this experiment optimizes process condition of flavonoid in Trollius chinensis through water extraction and ethanol extraction. The result shows that flavonoid extraction rate of Trollius chinensis through ethanol extraction method is obviously higher than water extraction, and the optimal extraction process condition is: ethanol concentration is 75%, extraction time is 90min, extraction times are 3, and fluid material ratio is 20:1. 展开更多
关键词 planted Trollius chinensis flavonoid water extraction ethanol extraction method process study
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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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Changes in Soil Hot-Water Extractable C,N and P Fractions During Vegetative Restoration in Zhifanggou Watershed on the Loess Plateau 被引量:2
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作者 UE Sha LI Peng +2 位作者 LIU Guo-bin LI Zhan-bin ZHANG Chao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2250-2259,共10页
The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extr... The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extractable fractions could be used as indicators of soil quality change in Loess Plateau.The six vegetation types established in 1975 were(i) Robinia pseudoacacia L.,(ii) Caragana korshinkii Kom.,(iii) Pinus tabulaeformis Carr.,(iv) P.tabulaeformis-Amorpha fruticosa L.,(v) R.pseudoacacia-A.fruticosa,and(vi) grassland.A cropped hillslope plot and a Platycladus orientalis L.native forest plot were used as references.The results indicated that the conversion of native forest to cropland resulted in a significant decline in the hot-water extractable C,N and P fractions.Hot-water extractable C,N,and P increased when cultivated land was revegetated,but after 30 years the amount of hot-water extractable C,N,and P in revegetated fields was still much lower compared to native forest.Hot-water extractable fractions increased more under mixed-forest than under pure-forest stands.Furthermore,there was a significant correlation between the hot-water extractable fractions and soil chemical and microbiological properties.The results showed that hot-water extractable fractions could be used as indicators of soil quality change on the Loess Plateau. 展开更多
关键词 soil hot-water extractable fraction vegetative restoration Loess Plateau
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