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Effects of Manual, Cultural, Botanical and Chemical Treatments of Termite Control in Hamelmalo Agricultural College Area 认领
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作者 Biniam Efriem Habteab Goitom +2 位作者 Rayet Idris Yosief Girmay Adungna Haile 《生态学期刊(英文)》 2021年第1期64-74,共11页
Termites are the most serious pests of field and horticultural crops, forests, and wooden household furniture. In Hamelmalo Agricultural College (HAC) the infestation of termite is very high resulting in great destruc... Termites are the most serious pests of field and horticultural crops, forests, and wooden household furniture. In Hamelmalo Agricultural College (HAC) the infestation of termite is very high resulting in great destruction of crop plants and wooden office and dormitory furniture. The devastating attack of termites should be managed by using best and ecofriendly management method. The purpose of the study was to compare the effectiveness of manual destruction of mounds and killing of termite queen and king, chemical chlorpyrifos, seed and leaves extract of neem and Lantana (as separate experiment) and smoke on termite control. Termite mounds were selected randomly inside HAC compound. The materials used were hand hoe, spade, fork, water, 20 L jar and protective clothes. The treatments were replicated three times. The botanical treatments were prepared at 2 L of highly concentrated extracts per 20 L of water each. Chlorpyrifos was applied at 20 ml per 20 L of water. Dried woody plants were used for smoke treatment. Careful digging was done to avoid king escape and queen rupture and they were killed by burning. Among all, the mechanical destruction and killing of king and queen and chlorpyrifos resulted in a complete control of the termite population. Except in the mounds treated by chlorpyrifos, the activity of termite population was very active and they closed the opened galleries immediately after treatment even though there were dead termite castes in all treatments. Living termite castes were counted by taking a medium size spade of broken mound pieces. The highest count was recorded from mounds treated by smoke. After two weeks the queen and king in every treatment mound were cheeked and killed for those who were alive. Except by the chlorpyrifos and manual destruction of mound (king and queen were killed before) all the royal families were alive and killed. Controlling of termite population in the field (outside their mound) is not possible due to the hidden foraging activity of termites, environmental safety 展开更多
关键词 Termite Castes MOUNDS CULTURAL Mechanical Chlorpyrifos Lantana Seed and Leaf Extract Neem Leaf and Seed Kernel Extract
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中草药东风菜水和醇提取物的镇痛作用研究 认领
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作者 孙展鹏 高长久 +2 位作者 周雪 宋高臣 梁春娥 《中国中医药现代远程教育》 2021年第4期152-154,共3页
目的对中草药东风菜水和醇2种提取物的镇痛效果进行评价。方法采用水和75%乙醇2种溶剂分别对东风菜药材进行提取,通过冰醋酸致小鼠扭体实验、热板致小鼠足痛实验观察东风菜水和醇2种提取物的镇痛作用。结果与生理盐水组比较,东风菜2种... 目的对中草药东风菜水和醇2种提取物的镇痛效果进行评价。方法采用水和75%乙醇2种溶剂分别对东风菜药材进行提取,通过冰醋酸致小鼠扭体实验、热板致小鼠足痛实验观察东风菜水和醇2种提取物的镇痛作用。结果与生理盐水组比较,东风菜2种提取物高(7.2 g/kg)、低(3.6 g/kg)剂量组对冰醋酸致小鼠扭体和热板致小鼠足痛有明显的抑制作用(P<0.01,P<0.05),且存在量效关系。结论东风菜具有较好的镇痛作用,其水提物的镇痛效果优于醇提物。 展开更多
关键词 东风菜 提取物 镇痛 实验研究 水提物 醇提物 中药化学
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基于AB-8大孔吸附树脂制备余甘子果实精制物及其在卷烟中的应用 认领
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作者 叶烨 李东亮 +2 位作者 耿宗泽 杜树山 徐恒 《烟草科技》 CAS CSCD 北大核心 2021年第2期52-57,共6页
为解决天然香原料粗提物在卷烟中的应用受限问题,充分发挥天然植物多元成分在卷烟加香加料中的作用,利用AB-8型大孔吸附树脂对余甘子果实提取物进行精制加工,采用HPLC法定量分析了以没食子酸为代表的酚酸类成分精制前后质量分数的变化,... 为解决天然香原料粗提物在卷烟中的应用受限问题,充分发挥天然植物多元成分在卷烟加香加料中的作用,利用AB-8型大孔吸附树脂对余甘子果实提取物进行精制加工,采用HPLC法定量分析了以没食子酸为代表的酚酸类成分精制前后质量分数的变化,评价了余甘子果实精制物在卷烟中的应用效果。结果表明:(1)不同提取溶液的余甘子果实粗提物,其化学成分差异明显;根据提取得率和感官评价结果,纯水提取为最佳。(2)经AB-8型大孔吸附树脂精制处理的纯水洗脱流份,即为余甘子果实精制物,干物质得率达65.9%,实现了有效成分的富集。(3)精制前后,没食子酸的质量浓度由0.538 mg/mL提升至1.317 mg/mL。(4)余甘子果实精制物对卷烟烟气的修饰作用明显优于粗提物,在柔和烟气、增加烟气量和改善抽吸品质方面效果更佳。 展开更多
关键词 余甘子 提取物 卷烟 大孔树脂 精制物 没食子酸 感官评价
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酶与超声波协同提取乌龙茶碎茶中水浸出物的研究 认领
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作者 张国辉 《饮料工业》 2021年第1期14-18,共5页
本文以乌龙茶碎茶为原料,采用酶与超声波协同进行提取,以提高水浸出物的得率。在固定超声功率为500 W、超声波提取20min和茶水料液比为1∶20时,通过单因素实验探索单一的纤维素酶和果胶酶添加量、纤维素酶和果胶酶复合酶的添加量、单一... 本文以乌龙茶碎茶为原料,采用酶与超声波协同进行提取,以提高水浸出物的得率。在固定超声功率为500 W、超声波提取20min和茶水料液比为1∶20时,通过单因素实验探索单一的纤维素酶和果胶酶添加量、纤维素酶和果胶酶复合酶的添加量、单一或复合酶酶解时间对茶叶水浸出物提取得率的影响。研究表明:在纤维素酶与果胶酶复配比为1∶1、复合酶添加量为1.2%、酶解时间为60 min时,利用超声波辅助提取乌龙茶碎茶中的水浸出物提取率达到28.5%。 展开更多
关键词 乌龙茶 复合酶 超声波 提取 水浸出物
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Effect of Food Waste Compost (FWC) and its Non-Aerated Fermented Extract (NFCE) on Seeds Germination and Plant Growth 认领
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作者 Raja Jarboui Bilel Dhouib Emna Ammar 《土壤科学期刊(英文)》 2021年第2期122-138,共17页
The aim of this study was to investigate the effect of the food wastes compost (FWC) and its non-aerated fermented extract (NFCE) on seed germination and growth of tomato (<i>Solanum</i> <i>lycopersi... The aim of this study was to investigate the effect of the food wastes compost (FWC) and its non-aerated fermented extract (NFCE) on seed germination and growth of tomato (<i>Solanum</i> <i>lycopersicum</i> L.), watercress (<i>Nasturtium</i> <i>officinale</i>), chili pepper (<i>Capsicum</i> <i>annuum</i>), peas (<i>Pisum</i> <i>sativum</i> L.), chickpea (<i>Cicer</i> <i>arietinum</i>) and beans (<i>Vicia</i> <i>faba</i>) under greenhouse conditions. The FWC and NFCE were physico-chemically and microbiologically characterized. The NFCE effect was evaluated on tomato, watercress, and chili pepper seeds germination and seedling growth. However, for leguminous, pea, chickpea and bean seedlings, the FWC amended soils and irrigated with NFCE were tested for plants growth. The results of FWC analyses revealed that FWC has neutral pH, low EC and C/N ratio, with fertilizing elements (N, P, K and Mg) and lack of phytotoxic effect. The NFCE was characterized by low EC and relatively high carbon content (COD = 9700 mg/l), and intense microbial activity, notably mesophilic bacteria. Therefore, in fermented compost extract, mesophilic bacteria were increased by 225, yeasts by 25 and molds by 10 times compared to those of the investigated compost. In greenhouse, the diluted NFCE increased significantly (<i>p</i>< 0.05) germination and growth of the tested seedlings. Used alone, the FWC amended soil or the NFCE irrigated soil, improved the growth of tested seedlings. The use of soil amended with compost and irrigated by fermented compost extract decreased significantly the growth of the same experimented seedlings. Therefore, the FWC and its fermented extract were a suitable substrate for germination and growth of the studied seeds. 展开更多
关键词 Food Wastes COMPOST Fermented Compost Extract Seed Germination SEEDLING Growth
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Hepato-Preventive Effects of Hydroethanolic Leaves Extract of <i>Persea</i>Americana, Mill (Lauraceae) “Avocado” against Antouka Super<sup>®</sup>Induced Damage in Male Japanese Quail (<i>Coturnix coturnix</i>Japonica) 认领
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作者 Ngoumtsop Victor Herman Tchoffo Herve +2 位作者 Guiekep Nounamo Arthénice Jemima Mutwedu Valence Ngoula Ferdinand 《兽医学(英文)》 2021年第1期41-56,共16页
The present study was undertaken to evaluate the protective effects of Hydroethanolic leaves extract of <em>Persea americana</em> (HEPA) against Antouka Super<sup><span style="font-family:Ver... The present study was undertaken to evaluate the protective effects of Hydroethanolic leaves extract of <em>Persea americana</em> (HEPA) against Antouka Super<sup><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&reg;</sup></span>(AS) induced hepatotoxicity in male Japanese quail. In total, 40 immature male Japanese quails aged 28 days were used and divided equally into 5 groups. The groups were designed as the control group (received only a 10 ml/kg of distilled water) and the AS group (75 mg/kg b.w). Other three groups received AS (75 mg of AS/kg b.w) plus HEPA (50, 100, and 200 mg/kg b.w/day respectively) by the oral route. After 60 days of the experiment, the crushed liver was performed to obtain homogenate. The protective effects of HEPA on the biochemical parameters, oxidative stress biomarkers and histology changes in the liver were evaluated. The results indicated that AS treatment caused significant alterations in the clinical signs and behavior. It induces the increase in the content of Urea, Creatinine, Protein, AST and ALT in liver tissues and serum. The activities of enzymatic oxidative stress markers such as Superoxide Dismutase (SOD);Catalase (CAT) and Total Peroxidase (POD) also showed significant perturbations in AS-treated quails. Histopathological examination of the liver of AS-treated quails revealed liver lesions characterized by moderate to severe degenerative changes showing a number of hepatocytes undergo fatty changes, focal aggregation of the lymphocytes, multiple necrotic changes and inflammatory infiltrate. The administration of HEPA however, markedly ameliorated the toxicity of AS by protecting the levels of aforesaid biomarkers to near normal levels. These results suggested that HEPA due to its phytochemical constituents with antioxidant properties possesses significant effects against AS-induced toxicity. However, these effects were more pronounced at a dose of 200 mg/kg bw. 展开更多
关键词 Antouka Super® (AS) Hepatoprotective Toxicity Hydroethanolic Leaves Extract Persea americana Japanese Quail
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Antimicrobial and Antioxidant Activities of Methanolic Extract and Fractions of <i>Epilobium roseum</i>(Schreb.) against Bacterial Strains 认领
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作者 Muhammad Ikram Niaz Ali +5 位作者 Gul Jan Farzana Gul Jan Muhammad Romman Muhammad Ishaq Yasir Islam Naeem Khan 《美国植物学期刊(英文)》 2021年第3期275-284,共10页
Present study aims to evaluate antimicrobial and antioxidant activities of the crude methanolic extract and different fractions of the <i><span style="font-family:Verdana;">Epilobium</span>... Present study aims to evaluate antimicrobial and antioxidant activities of the crude methanolic extract and different fractions of the <i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb). The extract and fractions were used against pathogenic bacteria (</span><i><span style="font-family:Verdana;">Bacillus</span></i> <i><span style="font-family:Verdana;">subtilis</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Bacillus</span></i> <i><span style="font-family:Verdana;">atrophaeus,</span></i> <i><span style="font-family:Verdana;">Klebsiella</span></i> <i><span style="font-family:Verdana;">pneumonia</span></i> <span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">Pseudomonas</span></i> <i><span style="font-family:Verdana;">aeruginosa</span></i><span style="font-family:Verdana;">) and fungal strains (</span><i><span style="font-family:Verdana;">Aspergillus</span></i> <i><span style="font-family:Verdana;">niger</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Aspergillus</span></i> <i><span style="font-family:Verdana;">flavus</span></i><span style="font-family:Verdana;">). The methanolic extract and their sub fraction n-hexane showed a prominent inhibition zone against all bacterial strains but inactive against fungal strains. </span><span style="font-family:Verdana;">The various extracts of </span><i><span style="font-family:Verdana;">Epilobium</span></i> <i><span style="font-family:Verdana;">roseum</span></i> <span style="font-family:Verdana;">(Schreb) from various parts were tested for their antioxidant activity by</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">1,1-Diphenyl-2-picryl-hydrazyl (DPPH) assay</span><span style="font-family:;" "=""><span style="font-family:Verdana;">. The IC</span><b><sub><span style="font-family:Verdana;font-size:12px;">50</span></ 展开更多
关键词 Methanolic Extract Epilobium roseum DPPH n-Hexan Antioxidant Activity
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Acetone Extract of <i>Dioscorea alata</i>Inhibits Cell Proliferation in Cancer Cells 认领
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作者 Kenroy Wallace Helen Asemota Wesley Gray 《美国植物学期刊(英文)》 2021年第3期300-314,共15页
<em>Dioscorea</em><span style="font-family:;" "=""><span style="font-family:Verdana;"> spp., White Yam has been shown to exhibit a wide range of nutritional a... <em>Dioscorea</em><span style="font-family:;" "=""><span style="font-family:Verdana;"> spp., White Yam has been shown to exhibit a wide range of nutritional and medicinal properties. However, the compounds associated with its medicinal functions have not been fully examined. The purpose of this study was to generate a chemoinformatic profile of the bioactive compounds present in </span><i><span style="font-family:Verdana;">Dioscorea</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">alata</span></i><span style="font-family:Verdana;"> (</span><i><span style="font-family:Verdana;">D</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">alata</span></i><span style="font-family:Verdana;">) and to characterize their putative anti-cancer properties using prostate (DU145) and lung (A549) cancer cells. Chemoinformatic profiling of </span><i><span style="font-family:Verdana;">D</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">alata</span></i><span style="font-family:Verdana;"> resulted in five bioactive extracts</span></span><span style="font-family:Verdana;">:</span><span style="font-family:Verdana;"> hexane (DaJa-1), ether (DaJa-2), acetone (DaJa-3), ethanol (DaJa-4) and water (DaJa-5) were generated. The analytes present in the five bioactive extracts were dissolved in 0.1% DMSO and their anti-cancer activity </span><span style="font-family:Verdana;">were </span><span style="font-family:Verdana;">determined. We observed that the acetone extract (DaJa3) was the only extract capable of inducing greater tha</span><span style="font-family:Verdana;">n</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> 90% cell death of DU 145 cell at 100 μg/mL. The order of growth inhibition of the extracts in DU-145 cell is DaJa-3 (IC50, 31.45 μg/mL) > DaJa-4 (IC50 60 μg/mL) > DaJa-1 (IC50 > 100 μg/mL) ≥ DaJa-2 (IC50 > 100 μg/mL) ≥ DaJa-5 (IC50 > 100 μg/mL). MTT cell viability, dye excl 展开更多
关键词 Dioscorea alata Acetone Extract Anticancer Activity White Yam
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北京特色炮制饮片炒白扁豆仁质量标准研究 认领
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作者 张伟娜 赵颖 李铮 《河南中医》 2021年第2期289-293,共5页
目的:建立北京特色炮制饮片炒白扁豆仁的质量标准。方法:采用直观法描述炒白扁豆仁性状;薄层色谱(thin loyer chromatography,TLC)薄层鉴别法进行鉴别;根据《中华人民共和国药典》2020年版方法测定炒白扁豆仁杂质、水分、总灰分、酸不... 目的:建立北京特色炮制饮片炒白扁豆仁的质量标准。方法:采用直观法描述炒白扁豆仁性状;薄层色谱(thin loyer chromatography,TLC)薄层鉴别法进行鉴别;根据《中华人民共和国药典》2020年版方法测定炒白扁豆仁杂质、水分、总灰分、酸不溶性灰分、浸出物、二氧化硫残留量。结果:炒白扁豆仁性状为2枚子叶多分离,完整者呈扁椭圆形或扁卵圆形,表面微黄色至橙黄色,或偶见焦斑,具轻微独特焦豆香气;TLC薄层鉴别中炒白扁豆仁在与派可林酸对照品相应位置上,显相同颜色的斑点,且斑点清晰;同时检测出水分不得超过11.0%,总灰分不得超过5%,酸不溶性灰分不得超过1%,30%乙醇浸出物不少于15%。初步拟定了炒白扁豆仁的质量标准。结论:该标准可为北京特色炮制饮片炒白扁豆仁的质量控制提供参考依据。 展开更多
关键词 炒白扁豆仁 质量标准 派可林酸 浸出物
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Sub-chronic toxicity of the aqueous wood-ash extract of Parkia biglobosa in Mus musculus 认领
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作者 Timothy Auta 《TMR生命研究》 2021年第1期9-17,共9页
Considering the possible health hazards associated with consumption of aqueous wood-ash extracts,this study investigated the sub-chronic toxicity of aqueous wood-ash extract of Parkia biglobosa on Mus musculus.Parkia ... Considering the possible health hazards associated with consumption of aqueous wood-ash extracts,this study investigated the sub-chronic toxicity of aqueous wood-ash extract of Parkia biglobosa on Mus musculus.Parkia biglobosa(5 kg)were collected and aqueous extracts of wood-ash were prepared by percolation method.Doses of 0(control),5,50 and 100 mg/kg,once a day,were administered to mice(n=10/treatment)90 days.Blood was collected by retro-orbital phlebotomy and assayed for serum creatinine,aspartate aminotransferase and alanine aminotransferase,and the kidney and liver were excised for histopathology using standard methods.Data were analysed using descriptive statistics and ANOVA atα0.05.Serum creatinine(mg/dL),aspartate aminotransferase(UI/L)and ALT(UI/L)increased with dosage and peaked at 100 mg/kg:2.1±0.2,128.8±8.0 and 58.0±2.9 compared to the control:0.8±0.1,89.8±5.1 and 28.5±1.4.Tubular degeneration and necrosis in the kidney,hepatocyte atrophy and dissociation of cords in the liver were observed at the 100 mg/kg dose level,while control organs had normal tissue architecture.Aqueous wood-ash extracts of P.biglobosa showed sub-chronic toxicity in Mus musculus. 展开更多
关键词 Wood-ash extract Parkia biglobosa Pathology BIOCHEMISTRY NECROSIS
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中药超临界流体萃取技术专利分析 认领
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作者 齐悦如 卞志家 《山东化工》 CAS 2021年第3期89-92,共4页
超临界流体提取法是目前国际上用于提取分离的先进技术之一。已经被大量应用于中药研究开发,有相当部分已经投入生产。以中药超临界流体萃取技术的专利为切入点,重点分析了提取工艺的技术演进以及研究热点和前沿技术,为国内药企对该技... 超临界流体提取法是目前国际上用于提取分离的先进技术之一。已经被大量应用于中药研究开发,有相当部分已经投入生产。以中药超临界流体萃取技术的专利为切入点,重点分析了提取工艺的技术演进以及研究热点和前沿技术,为国内药企对该技术的合理创新和研究提供有益借鉴。 展开更多
关键词 超临界 中药 提取 黄酮
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4种中药材提取物对桃粉蚜的室内毒力 认领
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作者 刘宝生 胡瑞瑞 +1 位作者 白鹏华 李建成 《山东农业科学》 2021年第1期105-108,共4页
本研究采用浸虫浸液法测定蛇床子、苍耳、防风和麻黄4种中药材提取物对桃粉蚜的触杀作用。结果表明,4种中药材提取物均对桃粉蚜有明显的触杀效果,总的来说,24 h和48 h校正死亡率均为蛇床子>苍耳>防风>麻黄;对桃粉蚜24 h毒力最... 本研究采用浸虫浸液法测定蛇床子、苍耳、防风和麻黄4种中药材提取物对桃粉蚜的触杀作用。结果表明,4种中药材提取物均对桃粉蚜有明显的触杀效果,总的来说,24 h和48 h校正死亡率均为蛇床子>苍耳>防风>麻黄;对桃粉蚜24 h毒力最强的是蛇床子,LC50值为0.346 mg/mL;48 h毒力最强的是苍耳,LC50值为3.300×10^-3 mg/mL。本研究结果可为开发植物源杀蚜剂提供理论依据。 展开更多
关键词 桃粉蚜 中药材 提取物 触杀作用 室内毒力
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GC-O和GC-MS结合鉴定白兰花挥发油中的特征香气组分及应用 认领
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作者 张伟 林德洪 +1 位作者 林伟锋 王延平 《山东化工》 CAS 2021年第3期104-108,共5页
主要是从水蒸汽蒸馏法(HD)、有机溶剂(石油醚)提取法(SE)与超临界超临界流体(CO2)萃取(SFE)三种方法提取白兰花挥发油,分别为HD-挥发油、SE-挥发油、SFE-挥发油,然后采用气相色谱-质谱联用(GC-MS)和气相色谱-电子鼻联用(GC-O)对这三... 主要是从水蒸汽蒸馏法(HD)、有机溶剂(石油醚)提取法(SE)与超临界超临界流体(CO2)萃取(SFE)三种方法提取白兰花挥发油,分别为HD-挥发油、SE-挥发油、SFE-挥发油,然后采用气相色谱-质谱联用(GC-MS)和气相色谱-电子鼻联用(GC-O)对这三种方法提取的白兰花挥发油成分进行分析研究,确定白兰花挥发油中的关键香气组分,以及白兰花挥发油在烟草加香应用上的研究。得到SFE-挥发油的香气清新自然,有明显的白兰花特征香气;嗅闻香味较HD-挥发油、SE-挥发油的甜润感更足、清香更突出。通过对挥发油成分比较分析发现,SFE-挥发油的特征香味物质为5种,它们分别为芳樟醇、柠檬醛、苯乙醇、香叶醇和反式-橙花叔醇,即挥发油的关键致香组分。添加在卷烟中,挥发油均有提高卷烟的清甜花香感、细腻烟气、提高烟气丰富性等作用。其中,SFE-挥发油的评分最高,更好地提升了烟气自然清新感、甜润感。 展开更多
关键词 白兰花 提取 挥发油 GC-MS GC-O 香气组分 加香应用
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基于高分六号WFV数据的冬小麦种植面积提取 认领
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作者 刘宝康 王仁军 +4 位作者 尤晓妮 于志远 南岭 张起升 黄炳婷 《测绘与空间地理信息》 2021年第1期1-4,共4页
冬小麦是我国重要的粮食作物之一,准确获取冬小麦种植面积具有重要的现实意义。为探究高分六号卫星影像进行冬小麦遥感监测的可行性和精确性,本文选取甘肃省崆峒区为研究区,运用红边波段+监督分类中的支持向量机法,提取了2019年崆峒区... 冬小麦是我国重要的粮食作物之一,准确获取冬小麦种植面积具有重要的现实意义。为探究高分六号卫星影像进行冬小麦遥感监测的可行性和精确性,本文选取甘肃省崆峒区为研究区,运用红边波段+监督分类中的支持向量机法,提取了2019年崆峒区冬小麦种植面积,并利用混淆矩阵对分类结果进行精度验证。结果表明:提取崆峒区冬小麦种植面积为15045 hm 2,与实际种植面积相比,误差率为1.02%;该模型能有效地提取崆峒区冬小麦,总体精度为98.88%,Kappa系数为0.97;红边波段能有效地提取干扰地物,提取精度比直接使用监督分类高7.88个百分点;GF6影像在提取冬小麦种植面积上具有明显优势。 展开更多
关键词 GF6 崆峒区 冬小麦 面积 提取
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谷物脂肪酶活测定方法的改进研究 认领
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作者 李红梅 李云龙 +1 位作者 程哲 胡俊君 《粮食与油脂》 北大核心 2021年第1期102-104,共3页
对谷物脂肪酶活检测的国家标准方法中的样品提取、转移方面进行了改进,以期提高谷物脂肪酶活检测的可操作性。同时,对国标法和改进法的测定结果进行比较分析。结果表明,采用改进法与现行常规检测方法结果一致,其准确性和重复性更容易实... 对谷物脂肪酶活检测的国家标准方法中的样品提取、转移方面进行了改进,以期提高谷物脂肪酶活检测的可操作性。同时,对国标法和改进法的测定结果进行比较分析。结果表明,采用改进法与现行常规检测方法结果一致,其准确性和重复性更容易实现,减少了样品转移过程中的人为误差,是一种简便、高效的测定方法。 展开更多
关键词 脂肪酶活 测定方法 改进 提取
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车前草浸出物测定方法的建立及熵权TOPSIS法评价车前草药材质量 认领
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作者 田甜 纪玉华 +3 位作者 王寿富 陈丹燕 刘远俊 程学仁 《广东药科大学学报》 CAS 2021年第1期16-22,共7页
目的建立车前草浸出物的测定方法,为车前草药材质量评价提供依据。方法采用HPLC法建立不同产地车前草的浸出物特征图谱,同时测定车前草浸出物中大车前苷、木犀草苷和车前草苷D 3个成分的质量分数。以车前草浸出物质量分数、特征图谱共... 目的建立车前草浸出物的测定方法,为车前草药材质量评价提供依据。方法采用HPLC法建立不同产地车前草的浸出物特征图谱,同时测定车前草浸出物中大车前苷、木犀草苷和车前草苷D 3个成分的质量分数。以车前草浸出物质量分数、特征图谱共有峰总面积及3个指标成分的总质量分数为综合评价指标,结合层次分析法与熵权TOPSIS法进行综合评分,优选车前草浸出物最佳测定方法,并运用熵权TOPSIS法评价不同产地车前草药材质量。结果车前草浸出物的测定方法选择热浸法,以75%乙醇为溶媒。熵权TOPSIS法表明江苏、江西两省的车前草质量优于安徽、四川两省的车前草。结论建立的车前草浸出物测定方法简便可行、重复性好,可用于完善车前草药材的质量控制。 展开更多
关键词 车前草 浸出物 特征图谱 层次分析法 熵权TOPSIS法
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大泵提效技术探索 认领
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作者 白璐 尚玉星 +2 位作者 孙鹏 罗晓坤 孙起 《石油石化节能》 2021年第3期29-31,I0005,共4页
为了进一步提高陆梁油田开发的综合效益,提出了机采系统“降杆速”的生产思路,并给出了理论依据,现场实施242井,平均杆速由18.4m/min降到13.0 m/min;系统效率由21.94%提高至31.21%,吨液单耗由7.38 kWh/t降低为5.54 kWh/t,节能率24.93%... 为了进一步提高陆梁油田开发的综合效益,提出了机采系统“降杆速”的生产思路,并给出了理论依据,现场实施242井,平均杆速由18.4m/min降到13.0 m/min;系统效率由21.94%提高至31.21%,吨液单耗由7.38 kWh/t降低为5.54 kWh/t,节能率24.93%。同时针对油田含水逐年上升的开发趋势,在“低杆速”的原则下,优选“潜力井”实施升级泵径提液增油的措施,现场实施38井,增液1354.6 t/d,增油85.4 t/d,历时6个月累计增液253218 t、累计增油17355 t。经现场实践,形成了一套“降杆速、保产量”的大泵提效技术。 展开更多
关键词 “降杆速” 大泵 提效 提液 产液单耗
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栀子有效部位的溃疡性结肠炎活性及其化学成分研究 认领
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作者 杨超 刘婧 +7 位作者 钟瑞 吴志瑰 裴建国 陈瑶 黄潇 高莎 阚瑞 付小梅 《中国药理学通报》 CAS CSCD 北大核心 2021年第2期263-269,共7页
目的研究栀子浸膏35%和70%乙醇洗脱部位对2,4,6-三硝基苯磺酸(TNBS)/乙醇诱导的大鼠溃疡性结肠炎(ulcerative colitis,UC)的治疗作用,并采用液质联用鉴定活性洗脱部位的化学成分。方法采用TNBS诱导大鼠UC模型,不同洗脱部均按生药量2.1 g... 目的研究栀子浸膏35%和70%乙醇洗脱部位对2,4,6-三硝基苯磺酸(TNBS)/乙醇诱导的大鼠溃疡性结肠炎(ulcerative colitis,UC)的治疗作用,并采用液质联用鉴定活性洗脱部位的化学成分。方法采用TNBS诱导大鼠UC模型,不同洗脱部均按生药量2.1 g·kg-1连续灌胃给药7 d,进行体质量测定,疾病活动指数(DAI)评分,结肠组织病理评分,比较各组大鼠结肠组织中髓过氧化物酶(MPO)、超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)、肿瘤坏死因子-α(TNF-α)、白细胞介素-6 (IL-6)、白细胞介素-1β(IL-1β)水平。采用液质联用鉴定药效较好部位的化学成分。结果与模型组相比,35%洗脱部位组体质量下降明显改善,DAI和组织病理评分降低,组织中MPO、NO、MDA、TNF-α、IL-6及IL-1β含量均降低,SOD含量升高(P <0.01)。液质联用共鉴定出19个化学成分,其中11个为环烯醚萜类成分。结论栀子35%洗脱部位对UC大鼠有明显治疗作用,环烯醚萜类成分可能是其发挥作用的物质基础。 展开更多
关键词 栀子 提取物 溃疡性结肠炎 髓过氧化物酶 液质联用 超氧化物歧化酶
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抗寒月季“天山祥云”化学成分的初步提取分离 认领
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作者 陶晶 陈璟 +1 位作者 葛鹏 闫美静 《化工管理》 2021年第9期54-55,共2页
通过实验对比,确定抗寒月季新品种“天山祥云”中的化学组分提取溶剂及初步分离流动相的最佳技术参数,为进一步更精细地分离及研究其化学成分奠定基础。
关键词 活性组分 分离 提取
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鹿茸饮片浸出物提取方法的建立及多成分测定在质量评价中的应用 认领
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作者 陆雨顺 王泽帅 +3 位作者 毕晓东 夏蕴实 卢思 孙印石 《中草药》 CAS CSCD 北大核心 2021年第2期357-366,共10页
目的比较不同提取方式、不同溶剂、不同料液比、不同提取时间对鹿茸浸出物得率的影响,对15个产地养殖的60批鹿茸饮片中7种核苷类主要成分(尿嘧啶、鸟嘌呤、次黄嘌呤、黄嘌呤、尿苷、肌苷和鸟苷)进行分析,比较不同部位鹿茸饮片(蜡片、粉... 目的比较不同提取方式、不同溶剂、不同料液比、不同提取时间对鹿茸浸出物得率的影响,对15个产地养殖的60批鹿茸饮片中7种核苷类主要成分(尿嘧啶、鸟嘌呤、次黄嘌呤、黄嘌呤、尿苷、肌苷和鸟苷)进行分析,比较不同部位鹿茸饮片(蜡片、粉片、纱片和骨片)的差异。方法参照《中国药典》2015年版四部通则相关方法优化鹿茸浸出物的提取方法,建立鹿茸浸出物最佳提取工艺,采用UPLC法对60批不同批次鹿茸饮片7种核苷类成分进行测定,结合主成分分析(PCA)和正交偏最小二乘-判别分析(OPLS-DA)化学计量学方法对鹿茸饮片进行区分与比较。结果热浸法提取条件下水溶性浸出物含量显著高于冷浸法,同一批次来源不同部位鹿茸饮片的浸出物含量,骨片低于蜡片、粉片、纱片(P<0.05)。不同部位饮片中7种核苷类成分总量在0.95~5.20 mg/g。通过OPLS-DA得出5个主要差异性成分尿嘧啶、鸟嘌呤、次黄嘌呤、尿苷和鸟苷为不同部位鹿茸饮片之间含量变化差异较为显著的成分。结论建立的鹿茸浸出物提取方法简便高效,结合7种核苷类成分含量测定可将纱片、骨片、蜡片与粉片之间进行初步区分,从而用于鹿茸饮片的质量控制与评价,为进一步完善鹿茸质量标准提供科学依据。 展开更多
关键词 鹿茸 浸出物 核苷成分 正交偏最小二乘法-判别分析 质量控制 主成分分析
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