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New amide alkaloids from Piper longum fruits 被引量:1
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作者 Jun YANG Yao SU +5 位作者 Ji-Feng LUO Wei GU Hong-Mei NIU Yan LI Yue-Hu WANG Chun-Lin LONG 《Natural Products and Bioprospecting》 CAS 2013年第6期277-281,共5页
Three new amide alkaloids piperlongumamides A-C(1-3),together with 12 known ones(4-15),were isolated from the fruits of Piper longum.The structures of the new isolates were determined using spectroscopic data analyses... Three new amide alkaloids piperlongumamides A-C(1-3),together with 12 known ones(4-15),were isolated from the fruits of Piper longum.The structures of the new isolates were determined using spectroscopic data analyses.Cytotoxic activity of these amides against HL-60(human leukemia),A-549(human lung cancer),MCF-7(human breast cancer),SMMC-7721(human liver cancer)and SW480(human rectal cancer)cell lines were evaluated.Piperchabamide B(11)exhibited weak inhibitory activity against HL-60(IC_(50)=21.32μM),A-549(IC_(50)=23.82μM)and MCF-7(IC_(50)=16.58μM)cell lines. 展开更多
关键词 piperACEAE piper longum amide alkaloids piperlongumamides piperchabamide B CYTOTOXICITY
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基于Piper-层次聚类-灰色关联度的突水水源识别
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作者 潘军 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第S01期221-227,共7页
快速准确地识别煤矿突水的来源对于煤矿安全开采十分重要,是煤矿防治水的基础工作。基于Piper三线图-层次聚类-灰色关联度的综合方法对甘肃省某煤矿的突水水源进行了识别。工作面井下排水、断层裂隙水和顶板砂岩裂隙水的水化学类型均为S... 快速准确地识别煤矿突水的来源对于煤矿安全开采十分重要,是煤矿防治水的基础工作。基于Piper三线图-层次聚类-灰色关联度的综合方法对甘肃省某煤矿的突水水源进行了识别。工作面井下排水、断层裂隙水和顶板砂岩裂隙水的水化学类型均为SO_(4)-K·Na型水,地表水水化学类型为SO_(4)·HCO_(3)-Ca型水。在Piper三线图中,井下排水与其他类型水在图中的距离较远,初步判断井下排水是来自多种水源的混合水。通过层次聚类分析得到煤层开采产生的井下排水与顶板砂岩裂隙水以及断层裂隙水的水质特征相对距离较近,特征类似。最后,采用灰色关联度判别模型进行判断,结果表明煤层顶板裂隙水以及断层裂隙水与井下排水的关联度较好。综合上述3种方法可知,工作面开采产生的井下排水主要来源于顶板砂岩水和断层裂隙水,与地表水的关系较小。推测可能是在开采过程中地层扰动导致的顶板水补给以及导水裂隙带导通孔隙水补给。因此,顶板含水层和导水裂隙带的研究与探查是该煤矿今后防治水工作的重点。 展开更多
关键词 矿井突水 水源识别 水化学特征 piper三线图 层次聚类 灰色关联度
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Chemical Constituents from Piper wallichii 被引量:6
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作者 赵云 阮金兰 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第1期21-23,共3页
Aim To investigate the chemical constituents of Piper wallichii. Methods Five compounds were isolated by silica gel column chromatography and Sephadex LH-20 gel column chromatography, and the structures of compounds w... Aim To investigate the chemical constituents of Piper wallichii. Methods Five compounds were isolated by silica gel column chromatography and Sephadex LH-20 gel column chromatography, and the structures of compounds were identified by spectral analysis. Result Five compounds were identified as piperlonguminine (trans, trans) (1), 4-hydroxy-3,5-dimethoxy-benzoic acid (2), galgravin (3), β-sitosterol (4), and daucosterol (5). Conclusion Five compounds were isolated from Piper wallichii for the first time, and compounds 1 -3 were isolated from this genus far the first time. 展开更多
关键词 piper wallichii piperLONGUMININE 4-hydroxy-3 5-dimethoxy-benzoic acid galgravin
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Discussion on AFLP Molecular Markers in Piper methysticum and Pepper 被引量:2
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作者 施江 辛莉 +1 位作者 杨彦 郑学勤 《Agricultural Science & Technology》 CAS 2007年第3期5-10,19,共7页
The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 mate... The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 materials of P. methysticum, 21 maerials of cultivated and wild Pepper, 1 material of Peperomia pellucida belonged to different genus. Premiers with good band-type and high polymorphism and resolution were selected from 64 pairs of primers for AFLP amplification and the clustering analysis was conducted with MVSP3.13f software. 191 bands were amplified by 4 pairs of premiers, 189 of which had polymorphism, being 98.6%. 28 germplasms were classified into 6 different groups at the genetic similarity coefficient of 0.52 by silver staining AFLP, in which 6 materials of Piper methysticum were clustered into a single group, indicating that P. methysticum belonged to Pepper family of Pepper genus but were distantly related to the others. The research provided the basis for selecting rootstocks for P. methysticum graft, molecular identification of P. methysticum and the fingerprint construction of P. methysticum. 展开更多
关键词 piper methysticum PEPPER Amplified fragment length polymorphism
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Quantification of total phenol,flavonoid content and pharmacognostical evaluation including HPTLC fingerprinting for the standardization of Piper nigrum Linn fruits 被引量:3
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作者 Aftab Ahmad Asif Husain +3 位作者 Mohd Mujeeb Shah Alam Khan Hani Abdullah Anber Alhadrami Anil Bhandari 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第2期101-107,共7页
Objective:To carry out the physicochemical and phytochemical standardization with high performance thin layer chromatography fingerprinting of Piper nigrum L.(P.nigrum)fruits in order to ascertain the standard pharmac... Objective:To carry out the physicochemical and phytochemical standardization with high performance thin layer chromatography fingerprinting of Piper nigrum L.(P.nigrum)fruits in order to ascertain the standard pharmacognostical parameters of this king of spices.Methods:Many standardization parameters like extractive values,total ash value,water soluble ash value and acid insoluble ash,moisture content,loss on drying and pH values of P.nigrum L.fruits were analyzed.The method of Harborne was adopted for the preliminary phytochemicals screening.Analysis of total phenolic and flavonoid contents,pesticides residues,aflatoxin and heavy metals were also performed.CAMAG-high performance thin layer chromatography system was used for fingerprinting of methanolic extract of P.nigrum L.fruits.Results:The results of phytochemicals testing indicated the presence of carbohydrates,phenolic compounds,flavonoids,alkaloids,proteins,saponins,lipids,sterols and tannins in various solvent extracts.Total phenolic and flavonoid contents in methanolic extract were found to be 1.728 1 mg/g and 1.087 ug/g,respectively.Heavy metals concentrations were found to be within standard limits.Aflatoxins and pesticides residues were absent.Conclusions:The outcome of this study might prove beneficial in herbal industries for identification,purification and standardization of P.nigrum L.fruits. 展开更多
关键词 piper nigrum L.fruits piperACEAE HPTLC fingerprint Black PEPPER
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基于Piper-PCA-MLP神经网络的矿井涌水水源识别方法研究 被引量:5
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作者 刘旭东 张瑞 万宝 《中国煤炭地质》 2022年第7期50-55,共6页
为了快速准确地识别矿井涌水水源,提出一种基于Piper-PCA-MLP的矿井涌水水源判别模型。以乌东煤矿为例,通过Piper三线图揭示了矿区不同地下水含水层的水化学特征,筛选了来自矿区不同涌水含水层的23个水样,获得了22个代表涌水含水层的典... 为了快速准确地识别矿井涌水水源,提出一种基于Piper-PCA-MLP的矿井涌水水源判别模型。以乌东煤矿为例,通过Piper三线图揭示了矿区不同地下水含水层的水化学特征,筛选了来自矿区不同涌水含水层的23个水样,获得了22个代表涌水含水层的典型水样。选用Na^(+)+K^(+)、Ca^(2+)、Mg^(2+)、Cl^(-)、SO_(4)^(2-)、HCO_(3)^(-)、NO_(3)^(-)和TDS八种水化学指标作为判别指标,考虑到乌东煤矿含水层水质边界不明显和水化学组分差异性不大的特点,选择MLP神经网络作为模型识别的基础,为了解决MLP神经网络在面对高维数据时训练收敛较慢,建模时间较长等缺点,使用主成分分析算法对数据进行降维,提取三种主要指标作为判别因子。以22组水样数据中17组作为训练样本,5组作为测试样本建立PCA-MLP模型,为了凸显模型的可靠性和准确性,选取同一样本集对水样数据分别建立PCA-层次聚类模型、MLP、PCA-RBF模型,并对其判别结果进行分析比较。结果表明:经过PCA降维的MLP神经网络能够有效消除水样水化学指标间的相互影响,对第四系孔隙潜水,地表水判别正确率均为100%,对基岩裂隙孔隙水的判别正确率为92.3%,明显优于其它方法,可为矿井涌水水源的识别提供一种新方法。 展开更多
关键词 涌水水源 piper三线图 主成分分析 MLP神经网络 piper-PCA-MLP判别模型
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An Investigation of the Vegetative Anatomy of <i>Piper sarmentosum</i>, and a Comparison with the Anatomy of <i>Piper betle</i>(Piperaceae) 被引量:1
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作者 Vijayasankar Raman Ahmed M. Galal Ikhlas A. Khan 《American Journal of Plant Sciences》 2012年第8期1135-1144,共10页
This paper describes the detailed anatomy and micromorphology of the vegetative parts of Piper sarmentosum Roxb. (synonym, P. lolot C.DC.), which is a southeast Asian medicinal plant valued for its medicinal and culin... This paper describes the detailed anatomy and micromorphology of the vegetative parts of Piper sarmentosum Roxb. (synonym, P. lolot C.DC.), which is a southeast Asian medicinal plant valued for its medicinal and culinary uses. The study also compares the anatomy of the leaf, petiole, stem and root of P. sarmentosum with those of the well-characterized P. betle L. The leaves of both the species are morphologically comparable and have similar culinary uses. The present study showed that the leaves of both the species possess more or less comparable anatomical features with a few differences;whereas, the microscopic features of the petiole, stem, and root of the two species are distinctive. 展开更多
关键词 piper sarmentosum piper lolot piper betle piperACEAE ANATOMY Light and Scanning Electron Microscopy
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Amides,Isoquinoline Alkaloids and Dipeptides from the Aerial Parts of Piper mullesua 被引量:1
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作者 Meng-Yuan Xia Jun Yang +4 位作者 Pan-Hua Zhang Xiao-Nian Li Ji-Feng Luo Chun-Lin Long Yue-Hu Wang 《Natural Products and Bioprospecting》 CAS 2018年第6期419-430,共12页
One undescribedamide,pipermullesine A,twoundescribed isoquinoline alkaloids,pipermullesinesBand C,and six undescribed dipeptides,pipermullamides A–F,along with 28 known compounds,were isolated from the aerial parts o... One undescribedamide,pipermullesine A,twoundescribed isoquinoline alkaloids,pipermullesinesBand C,and six undescribed dipeptides,pipermullamides A–F,along with 28 known compounds,were isolated from the aerial parts of Piper mullesua.The structures of the undescribed compounds were elucidated based on the analysis of 1D and 2D NMR and MS data.Furthermore,the structures of pipermullesines A–Cwere confirmed by single crystal X-ray diffraction analysis.All isolates were evaluated for inhibitory activity against platelet aggregation induced by thrombin(IIa)or platelet-activating factor(PAF).(-)-Mangochinine,pellitorine,and(2E,4E)-N-isobutyl-2,4-dodecadienamide showed weak inhibitory activity against rabbit platelet aggregation induced by PAF,with IC_(50)values of 470.3μg/mL,614.9μg/mL,and 579.7μg/mL,respectively. 展开更多
关键词 piper mullesua piperACEAE ANTIPLATELET AMIDES Isoquinoline alkaloids
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Cyclohexene Epoxides from Piper polysyphorum
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作者 马迎 韩桂秋 《Journal of Chinese Pharmaceutical Sciences》 CAS 1993年第2期97-101,共5页
Three new cyclohexene epoxides,polysyphoside A,B and C,along with a known compound crotepoxide(4),were isolated from Piper polysyphorum C.DC.Based on spectroscopic analysis,their structures were established as 1-benzo... Three new cyclohexene epoxides,polysyphoside A,B and C,along with a known compound crotepoxide(4),were isolated from Piper polysyphorum C.DC.Based on spectroscopic analysis,their structures were established as 1-benzoyloxymethylene-2-hydroxy-3-benzoyloxy-1,6- epoxycyclohex-4-ene(1),1-benzoyloxymethylene-2-hydroxy-5-benzoyloxy-1,6-epoxycyclohex-3-ene (2)and 2-hydroxy-3-benzoyloxymethylene-5-benzoyloxy-1,6-epoxycyclohex-3-ene(3),respectively.It was the first time that(1),(2)and(3)had been isolated from a natural source. 展开更多
关键词 piper polysyphorum Cyclohexene epoxides Polysyphoxide A Polysyphoxide B Polysyphoxide C
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Insecticidal Activity of Piperine Isolated from Piper sarmentosum
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作者 Feng Gang Ye Huochun +5 位作者 Yuan Enlin Zhang Jing Yan Chao Jin Qian Peng Zhengqiang Fu Yue-guan 《Plant Diseases and Pests》 CAS 2014年第2期38-41,共4页
In order to clarify the insecticidal active ingredients of Piper sarmentosum,one active ingredient was isolated from ethanol extract of P. sarmentosum by bioassay-guided fractionation method. Its chemical structures w... In order to clarify the insecticidal active ingredients of Piper sarmentosum,one active ingredient was isolated from ethanol extract of P. sarmentosum by bioassay-guided fractionation method. Its chemical structures were identified to be piperine by MS,1H NMR,13C NMR. The insecticidal activity of piperine and ethanol extract of P. sarmentosum against Aleurodicus dispels Russell were tested by leaf dip method. The results showed that piperine and ethanol extract of P. sarmentosum exhibited strong insecticidal activity against adults and nymphs of A. dispels; LC50values against adults were 28. 59 and 224. 31 mg/L,and LC50values against nymphs were 65. 91 and 336. 68 mg/L,respectively. There was no significant difference between piperine and azadirachtin against adults and nymphs of A.dispels. Therefore,piperine might be one of the main insecticidal ingredients of P. sarmentosum. In addition,piperine and ethanol extract showed ovicidal activity with different mode of action,piperine reduced the survival rate of newly hatched nymphs while ethanol extract impacted hatch of eggs. 展开更多
关键词 Aleurodicus dispels Russell Insecticidal activity piper sarmentosum piperINE
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New Amides and Phenylpropanoid Glucosides from the Fruits of Piper retrofractum
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作者 Rong Tang Ya-Qiong Zhang +6 位作者 Dong-Bao Hu Xue-Fei Yang Jun Yang Myint Myint San Thaung Naing Oo Yi Kong Yue-Hu Wang 《Natural Products and Bioprospecting》 CAS 2019年第3期231-241,共11页
Two new amides(E)-N-cinnamoyl-2-methoxypiperidine(1)and(R)-1-(2-oxopyrrolidin-3-yl)-5,6-dihydropyridin-2(1H)-one(2),four new amide glucosides,retrofractosides A-D(3-6),and two new phenylpropanoid glucosides,retrofract... Two new amides(E)-N-cinnamoyl-2-methoxypiperidine(1)and(R)-1-(2-oxopyrrolidin-3-yl)-5,6-dihydropyridin-2(1H)-one(2),four new amide glucosides,retrofractosides A-D(3-6),and two new phenylpropanoid glucosides,retrofractosides E(7)and F(8),together with 24 known compounds(9-32)were isolated from the fruits of Piper retrofractum.The chemical structures of these new compounds were elucidated based on extensive spectroscopic analysis.All of these isolates(1-32)were evaluated for inhibitory activity against mouse platelet aggregation induced by the peptide AYPGKF-NH2.(E)-N-(Tetrahydro-2H-pyran-2-yl)cinnamamide(9)showed a weak inhibitory efect,with an inhibition ratio of 52.0%at a concentration of 150μM. 展开更多
关键词 piper retrofractum piperACEAE Antiplatelet AMIDES PHENYLPROPANOIDS
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Isolation of Bulk Amount of Piperine as Active Pharmaceutical Ingredient (API) from Black Pepper and White Pepper (<i>Piper nigrum</i>L.)
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作者 Zihan Rahman Khan Fatema Moni +4 位作者 Suriya Sharmin Muhammad Abdullah Al-Mansur Abdul Gafur Obaidur Rahman Farhana Afroz 《Pharmacology & Pharmacy》 2017年第7期253-262,共10页
In the pharmaceutical world the majority of the active pharmaceutical ingredients (API) have been obtained from the natural products. Piperine is such naturally occurring alkaloid which can be considered as major bioa... In the pharmaceutical world the majority of the active pharmaceutical ingredients (API) have been obtained from the natural products. Piperine is such naturally occurring alkaloid which can be considered as major bioactive phytochemical having broad spectrum of pharmacological activities. It is obtained from the most valuable ethnomedicinal spices peppercorns i.e. black pepper and white pepper, which are the fruits of the Asian vine Piper nigrum L. Because of the widespread traditional uses of this medicinal compound, present article reveals a simple and effective isolation method of bulk piperine. The novelty of this investigation is to provide an idea for utilizing such natural method of large scale commercial piperine production as API drug in spite of chemical synthesis. Piperine was isolated in a pure crystal form and characterized by its melting point, X-Ray diffraction (XRD) studies and spectral data, including two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy. Chromatographic techniques like Thin Layer Chromatography (TLC) and High Performance Liquid Chromatography (HPLC) were applied to determine the purity of the yielded piperine. It was found that piperine yield from black pepper was within 2.5% - 3.0% and from white pepper within 4.0% - 4.5% and the purity of the yielded piperine was found to be up to 98.5% for black pepper and 98.2% for white pepper. Considering this yield value and purity it is indicated that, such effective isolation method can be successfully utilized for industrial large-scale production commercially. According to the result, it can be claimed that, as a natural product the isolated piperine can also be utilized as API drug like other expensive chemically synthesized piperine in different drug formulation. 展开更多
关键词 piper nigrum L NMR Spectroscopy X-Ray Diffraction Studies BULK piperINE
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海上石油平台安全应急培训——以Piper Alpha平台火灾导致沉没事故为例 被引量:4
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作者 邓连军 刘祖德 《安全与环境工程》 CAS 2005年第3期81-83,共3页
回顾了发生在英国北海的一起海洋石油行业内的重大安全事故,对事故的经过和影响做了概述,并重点对人员死亡和安全培训的情况进行分析,从而为石油行业提供借鉴。
关键词 piper ALPHA 海洋石油 安全培训 死亡率
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Piper图解淮河流域江苏地区浅层地下水水质演化特征 被引量:36
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作者 陆徐荣 周爱国 +2 位作者 王茂亭 杨磊 陆华 《工程勘察》 CSCD 北大核心 2010年第2期42-47,共6页
在收集213份20世纪80年代浅层地下水水质资料和616组现状采集样品的基础上,利用不同时期水化学组成在区域Piper三线图上的集合发生的位移现象,揭示20多年来该区浅层水的内在变化规律,同时利用水化学类型图、统计数据加以佐证,最后探讨... 在收集213份20世纪80年代浅层地下水水质资料和616组现状采集样品的基础上,利用不同时期水化学组成在区域Piper三线图上的集合发生的位移现象,揭示20多年来该区浅层水的内在变化规律,同时利用水化学类型图、统计数据加以佐证,最后探讨区域浅层水演化的原因。研究结果表明,通过Piper图示所表达的浅层地下水水质演化规律统计数据、绘制水化学类型分布图等方法相比较,分析更简洁、直观、通俗易懂。通过分析还发现,区内浅层地下水资源可以通过合理利用而改善水质,进而为人们提供理想的水源。 展开更多
关键词 浅层地下水 水质分区 三线图 水化学类型
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山蒟(Piperhancei)的生态生物学特征 被引量:8
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作者 简曙光 李玲 +3 位作者 张倩媚 卢琼 叶育石 任海 《生态环境学报》 CSCD 北大核心 2009年第2期608-613,共6页
山蒟(Piper hancei)是一种有较高园林绿化价值的常绿藤本植物,通过样地调查及相关数据分析,对山蒟的形态解剖学、生理生态学、营养元素含量等生态生物学特征进行研究,结果表明:山蒟喜阴湿环境,耐贫瘠,适合在酸性赤红壤上生长,主要分布... 山蒟(Piper hancei)是一种有较高园林绿化价值的常绿藤本植物,通过样地调查及相关数据分析,对山蒟的形态解剖学、生理生态学、营养元素含量等生态生物学特征进行研究,结果表明:山蒟喜阴湿环境,耐贫瘠,适合在酸性赤红壤上生长,主要分布于热带亚热带地区光照适中或较弱的溪涧边、林下、树干或岩石上。其平均光合速率为4.07μmol·m-2·s-1,气孔导度为0.23mol·m-2·s-1,蒸腾速率为3.87mmol·m-2·s-1。山蒟对营养元素的利用率较高,植株体内加权平均养分含量为N2.00%、P0.20%、K2.11%、Ca0.94%、Na0.05%、Mg0.15%,其中叶片的N、K和Ca含量最高,枝的P和Mg含量最高。山蒟的生态生物学特征有利于其快速生长、覆盖、吸附攀援和适应环境。研究结果将为山蒟的引种、栽培及开发利用提供重要理论依据。 展开更多
关键词 山蒟 藤本 生态生物学特征 园林绿化 开发利用
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Piper三线图和特征离子在谢桥井田水源判别中的应用 被引量:4
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作者 杨立志 《黑龙江科技信息》 2016年第25期14-15,共2页
矿井突(涌)水是采矿过程中最具威胁的自然灾害之一。能否准确快速地判别矿井突水水源,不仅是矿井水文地质工作的主要内容,而且是煤矿防治水工作的重要基础。本文在分析了谢桥井田主要含水层水文地质特征的基础上,利用Aqua Chem软件分别... 矿井突(涌)水是采矿过程中最具威胁的自然灾害之一。能否准确快速地判别矿井突水水源,不仅是矿井水文地质工作的主要内容,而且是煤矿防治水工作的重要基础。本文在分析了谢桥井田主要含水层水文地质特征的基础上,利用Aqua Chem软件分别绘制出砂岩裂隙水和灰岩水的Piper三线图,经比较发现在Piper三线图中砂岩裂隙水和灰岩水分布区域存在明显差异,且砂岩裂隙水中次阴离子为HCO3-,而灰岩水中次阴离子为SO42-。根据这一特点,选定SO42-和HCO3-作为砂岩裂隙水和灰岩水的水源判别特征离子,通过对SO42-/HCO3-比值分析比较发现:砂岩裂隙水(除4煤底板砂岩裂隙水外)中SO42-/HCO3-比值小于0.55,正确回判率高达100%;灰岩水中SO42-/HCO3-比值大于等于0.55,正确回判率高达91%。 展开更多
关键词 谢桥井田 水源判别 piper三线图 特征离子 砂岩裂隙水 灰岩水
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基于Piper-PCA-Fisher模型的矿井突水水源识别 被引量:2
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作者 苏俏俏 黄平华 +2 位作者 丁风帆 胡永胜 郜鸿飞 《能源与环保》 2021年第10期122-127,共6页
矿井水害的发生时刻威胁着煤炭的安全生产,同时也造成了严重的经济损失。为了迅速和准确地识别突水水源,选用Piper三线图对采自矿区突水含水层的41个水样进行筛选,得到32个典型水样作为训练样本,采用主成分分析法提炼出3个主成分作为判... 矿井水害的发生时刻威胁着煤炭的安全生产,同时也造成了严重的经济损失。为了迅速和准确地识别突水水源,选用Piper三线图对采自矿区突水含水层的41个水样进行筛选,得到32个典型水样作为训练样本,采用主成分分析法提炼出3个主成分作为判别指标,建立了水源判别模型;采用留一交叉验证法对模型的预判分类稳定性进行评价,模型对样本总体分类的准确率达到81.3%。并对焦作矿区11个未知水样进行水源判别,错误1个。并将预测结果与Fisher模型进行对比。结果表明,基于Piper-PCA-Fisher的判别模型能有效提高判别精度,为矿井安全生产提供保障,为矿井开展防治水工作及地下水资源合理开发利用提供理论依据。 展开更多
关键词 突水水源 piper三线图 主成分分析 Fisher理论 留一交叉验证法
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基于Piper图、灰色关联度和三维高密度电法的断层水源判别 被引量:8
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作者 施龙青 史雅迪 +3 位作者 邱梅 郭中安 杨建飞 姜海滨 《中国科技论文》 CAS 北大核心 2022年第1期1-8,共8页
为判别阳城煤矿3305工作面下平巷掘进遇到的FD53断层水的水源,进而决定巷道掘进是否可以直接穿过断层,在确定砂岩含水层、三灰含水层、奥灰含水层为FD53断层水可能水源的基础上,现场采集了断层及这3个含水层的水样进行常规化学成分水质... 为判别阳城煤矿3305工作面下平巷掘进遇到的FD53断层水的水源,进而决定巷道掘进是否可以直接穿过断层,在确定砂岩含水层、三灰含水层、奥灰含水层为FD53断层水可能水源的基础上,现场采集了断层及这3个含水层的水样进行常规化学成分水质检测。选取ρ(K^(+)+Na^(+))、ρ(Ca^(2+))、ρ(Mg^(2+))、ρ(HCO^(-)_(3))、ρ(Cl^(-))、ρ(SO^(2-)_(4))、pH、总溶解固体(total dissolved solids,TDS)作为水源识别化学指标,利用水化学特征Piper图排除了断层水水源为砂岩含水层的可能性;基于灰色关联模型,建立断层水和各含水层之间的灰色关联度,识别出断层水水源为三灰水;应用最新的三维高密度电法探测技术,获得了3个含水层在3305工作面的富水性分布特征,排除了断层水水源为奥灰水的可能性,并进一步判定断层水水源为三灰水。最终的判别结果表明,FD53断层水的水源为水量可控的三灰水,巷道掘进可以直接穿过断层。 展开更多
关键词 断层水源判别 piper三线图 灰色关联 三维高密度电法
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Modeling the Potential Geographic Distribution of Black Pepper(Piper nigrum)in Asia Using GIS Tools 被引量:4
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作者 HAO Chao-yun FAN Rui +5 位作者 Milton Cezar Ribeiro TAN Le-he WU Hua-song YANG Jian-feng ZHENG Wei-quan YU Huan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第4期593-599,共7页
Known as the "king of spices",black pepper(Piper nigrum),a perennial crop of the tropics,is economically the most important and the most widely used spice crop in the world.To understand its suitable bioclimatic d... Known as the "king of spices",black pepper(Piper nigrum),a perennial crop of the tropics,is economically the most important and the most widely used spice crop in the world.To understand its suitable bioclimatic distribution,maximum entropy based on ecological niche modeling was used to model the bioclimatic niches of the species in its Asian range.Based on known occurrences,bioclimatic areas with higher probabilities are mainly located in the eastern and western coasts of the Indian Peninsula,the east of Sumatra Island,some areas in the Malay Archipelago,and the southeast coastal areas of China.Some undocumented places were also predicted as suitable areas.According to the jackknife procedure,the minimum temperature of the coldest month,the mean monthly temperature range,and the precipitation of the wettest month were identified as highly effective factors in the distribution of black pepper and could possibly account for the crop's distribution pattern.Such climatic requirements inhibited this species from dispersing and gaining a larger geographical range. 展开更多
关键词 piper ngirum ENM bioclimatic distribution MAXENT
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Bioactivity guided isolation of mosquito larvicide from Piper longum 被引量:3
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作者 Madhu.S Kumar Vijayan VA Shaukath AK 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第2期112-116,共5页
Objective:To isolate the larvicidal component from the fruits of Piper longum(P.longum) against the filariasis vector,Culex quinquefasciatus(C.quinquefasciatus).Methods:Pulverized fruits of P.longum were subjected... Objective:To isolate the larvicidal component from the fruits of Piper longum(P.longum) against the filariasis vector,Culex quinquefasciatus(C.quinquefasciatus).Methods:Pulverized fruits of P.longum were subjected to soxhlet extraction using series of organic solvents of increasing polarity.All the solvent extracts were verified for their larvicidal efficacy against 4th instar larvae of C.quinquefasciatus employing standard WHO procedure.Bioassayguided fractionation through column chromatography lead to the isolation of a bioactive amide, pipyahyine from the petroleum ether extract.Results:Petroleum ether extract was found to be the most active fraction among all the extracts tested with LC<sub>50</sub> and LC<sub>90</sub> being 1.03 and 2.04 ppm respectively.Whereas,pipyahyine,an isolated component of the same fraction was found to be even more effective than the parent extract in terms of LC<sub>50</sub> being 0.58 and 1.88 ppm respectively. Conclusions:From the results,it is evident that P.longum can be considered as a powerful arsenal for the control of mosquito population. 展开更多
关键词 piper longum BIOASSAY Pipyahyine CULEX quinquefasciatus FILARIASIS LARVICIDE
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