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Bunte法制备氧乐果 被引量:4
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作者 孙致远 黄润秋 +2 位作者 陈其杰 柴有新 钱宝英 《农药》 CAS 北大核心 1990年第1期16-17,共2页
氧乐果1959年发现杀虫活性,1967年西德拜耳公司试制生产。此药具有强烈的触杀作用和内渗作用,是较理想的根、茎内吸传导性杀螨、杀虫剂,特别适于防治刺吸性害虫,效果优于乐果和内吸磷,不易产生抗性,并可降低易产生抗性的拟除虫菊酯的抗... 氧乐果1959年发现杀虫活性,1967年西德拜耳公司试制生产。此药具有强烈的触杀作用和内渗作用,是较理想的根、茎内吸传导性杀螨、杀虫剂,特别适于防治刺吸性害虫,效果优于乐果和内吸磷,不易产生抗性,并可降低易产生抗性的拟除虫菊酯的抗性。因此,氧乐果在国内外越来越受欢迎,需求量不断扩大。 展开更多
关键词 氧乐果 杀虫剂 bunte法
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Bunte盐法合成巯基乙酸异辛酯 被引量:8
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作者 彭辉 揭嵘 刘利君 《化学工业与工程》 CAS 1994年第2期42-45,共4页
本文以氯乙酸、异辛醇和硫代硫酸钠为主要原料,采用Bunte盐法,合成了巯基乙酸异辛酯。通过实验,确定了工艺流程,选取了最佳的工艺条件。并对合成氯乙酸异辛酯的酯化反应进行了研究。
关键词 bunte盐 巯基 乙酸异辛酯 合成
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用Bunte Salts法合成苯甲醛二正丁硫醇缩醛的研究 被引量:4
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作者 余爱农 胡家鑫 +2 位作者 张庆 杨坤国 孙宝国 《精细石油化工》 CAS CSCD 北大核心 1999年第2期31-33,共3页
以苯甲醛、硫代硫酸钠和溴代正丁烷为原料 ,用 Bunte Salts法合成苯甲醛二正丁硫醇缩醛。较好的反应条件是 :Bunte Salts与苯甲醛的摩尔比为 3.3∶ 1 ,催化剂浓盐酸的用量为 7.5m L,回流反应 9h。在该条件下产率达 79.5% ,并用 IR、1
关键词 bunteSalts法 合成 苯甲醛二正丁硫醇缩醛 香料
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Jankowski’s Bunting (Emberiza jankowskii): current status and conservation 被引量:7
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作者 王海涛 姜云垒 高玮 《Chinese Birds》 2010年第4期251-258,共8页
Jankowski’s Bunting (Emberiza jankowskii) is a small bird with narrow distribution ranges. It has experienced a drastic population decline during recent years and vanished from most of its historic breeding sites. It... Jankowski’s Bunting (Emberiza jankowskii) is a small bird with narrow distribution ranges. It has experienced a drastic population decline during recent years and vanished from most of its historic breeding sites. It has been recently up-graded as Endangered in the IUCN Red List of globally threatened species. By integrating unpublished data of field surveys conducted by us and published information on the species, we provide information on the status of distribution, breeding biology of the remaining population at the Dagang Forest Farm, population trends at currently known breeding sites, selection of breeding habitats and threats faced by the Jankowski’s Bunting. In light of its current status we also suggest ways and future research work related to protecting this bird species. 展开更多
关键词 Jankowski’s bunting DISTRIBUTION BREEDING population trend CONSERVATION
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用Bunte Salts法合成正丁醛二正丁硫醇缩醛的研究 被引量:5
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作者 余爱农 杨坤国 +2 位作者 黄在银 李佳凤 孙宝国 《香料香精化妆品》 CAS 北大核心 1998年第4期3-4,21,共3页
以正丁醛、硫代硫酸钠和溴代正丁烷为原料,用BunteSalts法合成正丁醛二正丁硫醇缩醛。较好的反应条件是:按本文实验量加入催化剂浓盐酸1.5mL,回流反应时间为9h。在该条件下反应产率达82.6%,用IR、1HNMR证实了其结构。
关键词 bunteSalts法 合成 正丁醛二正丁硫醇缩醛 香料
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Bunte盐法合成巯基乙酸异辛酯的工艺研究 被引量:1
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作者 王彦军 《有色矿冶》 2015年第1期23-24,27,共3页
主要论述了利用Bunte盐法合成巯基乙酸,并使用乙醚与异辛醇协同萃取工艺制取巯基乙酸负载有机相,再经过粗馏酯化、精馏提纯得到高纯度巯基乙酸异辛酯的合成工艺。
关键词 bunte盐法 巯基乙酸 协同萃取 粗馏 精馏 巯基乙酸异辛酯
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Bunte盐法制备巯基乙酸实验合成新方法
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作者 赵若冬 《兰州石化职业技术学院学报》 2006年第1期3-4,共2页
采用氯乙酸和碳酸钠反应生成氯乙酸钠,控制氯乙酸钠溶液PH值为8~9,在70—75℃下与等摩尔硫代硫酸钠反应生成Bunte盐,加入反应物重量10%的硫酸,控制温度为80~90℃,时间为80min进行酸化反应;再加入反应物重量2%的Zn粉在40~50... 采用氯乙酸和碳酸钠反应生成氯乙酸钠,控制氯乙酸钠溶液PH值为8~9,在70—75℃下与等摩尔硫代硫酸钠反应生成Bunte盐,加入反应物重量10%的硫酸,控制温度为80~90℃,时间为80min进行酸化反应;再加入反应物重量2%的Zn粉在40~50℃下还原80min,得到粗产品;萃取、精馏后巯基乙酸纯度可达98.6%,收率可达到89.7%。 展开更多
关键词 巯基乙酸 bunte盐 萃取 精馏
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Bunte盐法合成巯基醋酸工艺研究 被引量:9
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作者 彭辉 揭嵘 刘利君 《湘潭大学自然科学学报》 CAS CSCD 1994年第1期90-93,99,共5页
巯基醋酸是一种用途非常广泛的精细化工产品.本文研究了以氯乙酸钠和硫代硫酸钠为主要原料,采用Bunte盐法合成了巯基醋酸,并对各工艺条件进行了讨论.认为该法成本低、生产过程简便、易操作.生产灵活性大,且几乎无污染.
关键词 bunte盐 合成 巯基醋酸
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Assessment of Risk of Establishment of Wheat Dwarf Bunt (Tilletia controversa) in China
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作者 JIAWen-ming ZHOU Yi-lin +4 位作者 DUAN Xia-yu LUO Yong DING Sheng-li CAO Xue-ren Bruce D L Fitt 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期87-94,共8页
Wheat dwarf bunt, caused by Tilletia controversa Kühn (TCK), is an important quarantine wheat disease throughout the world. Based on published research results of the biology and the epidemiology of the disease... Wheat dwarf bunt, caused by Tilletia controversa Kühn (TCK), is an important quarantine wheat disease throughout the world. Based on published research results of the biology and the epidemiology of the disease, the main factors including temperature, humidity, snow cover, and their parameters relating to teliospore germination, infection and epidemics of TCK were determined. The geophytopathological models for the risk analysis of wheat dwarf bunt establishment were modified. Fifty-year meteorologic data from about 500 weather stations in China were used to calculate the probabilities of TCK establishment in different geographic sites with the models. The map that displays the establishment risk of TCK in winter wheat growing regions in China was generated by using geographical information system (GIS). The zones showing high, moderate, low, and very low, including no risk, of TCK establishment accounted for 27.33, 27.69, 38.12, and 6.86% of total winter wheat growing areas in China, respectively. These results will provide useful information to formulate quarantine regulations and wheat importation policy in China. 展开更多
关键词 wheat dwarf bunt geophytopathological model geographical information system risk analysis
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Morphology and morphometry of two hybridizing buntings at their hybrid zone in northern Iran reveal intermediate and transgressive morphotypes
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作者 Ali Gholamhosseini Mansour Aliabadian +1 位作者 Till Topfer Glenn-Peter Sætre 《Avian Research》 SCIE CSCD 2023年第4期523-532,共10页
The closely related Black-headed Bunting(Emberiza melanocephala,a western Palearctic lineage)and Red-headed Bunting(Emberiza bruniceps,an eastern Palearctic lineage)hybridize and replace each other south of the Caspia... The closely related Black-headed Bunting(Emberiza melanocephala,a western Palearctic lineage)and Red-headed Bunting(Emberiza bruniceps,an eastern Palearctic lineage)hybridize and replace each other south of the Caspian Sea.The parental species have distinct phenotypes and therefore morphology is useful for assessing hybridization in the contact zone.In the years of 1940 and 1977,quite a few hybrids were collected and studied morphologically.Since then,the hybrid zone appears to have expanded westwards,but there has been a time gap in the collection of morphological data.Here we reanalyze bunting specimens morphologically and compare the historical data with recent data.Morphometric and phenotypic traits from three time periods(1940,1977 and recent)were studied to assess phenotypic variation of hybrids,pattern of hybridization,and transgressive traits in the hybrid zone.Our results show that most of the birds in the hybrid zone exhibit intermediate phenotypes(both colors and morphometric characters),ranging from the pure phenotype of either of the parental species.However,hybridization has also produced novel phenotypes not seen in any of the parents.Using a canonical discriminant function analysis,the morphometric characters separated each parental species and the hybrids quite well.Our results showed morphometric intermediacy of hybrids in accordance with phenotypes.We observe a time trend in which recent hybrids are more similar to Red-headed Buntings phenotypically compared to historical samples.This pattern is likely a signature of a westward expansion of the Red-headed Bunting into the breeding range of the Black-headed Bunting. 展开更多
关键词 bunting HYBRIDIZATION Intermediate phenotypes Transgressive traits
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Sexual dimorphism and sex-differential migration of Little Buntings(Emberiza pusilla)at an East Asian stopover site
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作者 Sook-Young Cho Hyun-Young Nam +1 位作者 Se-Young Park Chang-Yong Choi 《Avian Research》 SCIE CSCD 2022年第1期87-93,共7页
Sex differences in morphology provide key information for understanding a species'morphological adaptations in relation to the evolution of sexual selection.In migratory birds,morphological traits have adapted to ... Sex differences in morphology provide key information for understanding a species'morphological adaptations in relation to the evolution of sexual selection.In migratory birds,morphological traits have adapted to long-distance travel,and sexual dimorphism is typically related to sex-differential migration phenology.Little Buntings(Emberiza pusilla)have one of the longest migrations and are the least dichromatic species among the Emberiza buntings.In this study,we measured sexual size dimorphism and sexual dichromatism of Little Buntings in relation to the spring arrival dates at a stopover site in Korea.Wing length was the most important predictor for identifying sex;the wings of males were longer than those of females.Males also had a significantly stronger chestnut color of the head feathers than females,but this color difference was more prominent in the spring than in the fall.Males arrived earlier than females by four days.Arrival dates correlated with both size and color,but unlike other bunting species previously studied in the same area,there was no clear sex-differential trend in the relationship between arrival date and morphological characteristics.Seasonal differences in the degree of sexual dichromatism suggest that chestnut plumage coloration can be used as a social or sexual signal of males in the breeding season.The correlation of size and color to early arrival regardless of sex may indicate that a preference for assortative mating exists or that a sex-differential migration strategy is not clearly defined in the early stages of northward migration.Our findings on the sexual dimorphism of Little Buntings provide insight into the evolution of the sex-differential migration of buntings in the East Asian Flyway. 展开更多
关键词 Digital photography Emberiza pusilla Little bunting Protandrous migration Sexual dichromatism Sexual dimorphism
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Mathematical Modeling of Heat Flux Distribution in Raw Cotton Stored in Bunt
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作者 Karimov Abdusamat Ismonovich Ismanov Muhammadziyo 《Engineering(科研)》 2020年第8期591-599,共9页
The scientific article examines the physical and mechanical properties of raw cotton stored in buntings in cotton palaces. Because during the storage of raw cotton in bunts, some of its properties deteriorate, some im... The scientific article examines the physical and mechanical properties of raw cotton stored in buntings in cotton palaces. Because during the storage of raw cotton in bunts, some of its properties deteriorate, some improvements. Therefore, the mathematical modeling of storage conditions of raw cotton in bunts and the physical and mechanical conditions that occur in it is of great importance. In the developed mathematical model, the main factor influencing the physical and mechanical properties of raw cotton is the change in temperature. Due to the temperature, kinetic and biological processes accumulated in the raw cotton in Bunt, it can spread over a large surface, first in a small-local state, over time with a nonlinear law. As a result, small changes in temperature lead to a qualitative change in physical properties. In determining the law of temperature distribution in the raw cotton in Bunt, Laplace’s differential equation of heat transfer was used. The differential equation of heat transfer in Laplace’s law was replaced by a system of ordinary differential equations by approximation. Conditions are solved in MAPLE-17 program by numerical method. As a result, graphs of temperature changes over time in raw cotton were obtained. In addition, the table shows the changes in density, pressure and mass of cotton, the height of the bun. As the density of the cotton raw material increases from the top layer of the bunt to the bottom layer, an increase in the temperature in it has been observed. This leads to overheating of the bottom layer of cotton and is the main reason for the deterioration of the quality of raw materials. 展开更多
关键词 Physical Mechanical Properties The bunt Parallelepiped The Mathematical Model Biological System Heat Processes Temperature Coefficient Experiment The Bulk Density Volumetric Density Humidity FIGURE Coordinate Axes The Laplace Differential Equation Transfer Solution Approximate MAPLE
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Control pattern of vocal center for vocalization in ruddy bunting(Emberiza rutila) 被引量:1
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作者 赵静 蒋锦昌 李东风 《Science China(Life Sciences)》 SCIE CAS 2003年第6期615-622,共8页
High vocal center (HVC) can produce single sound with one or two syllables by the sin-gle-type vocal control pattern in songbirds ruddy bunting (Emberiza rutila). It obviously shows left-side dominance in controlling ... High vocal center (HVC) can produce single sound with one or two syllables by the sin-gle-type vocal control pattern in songbirds ruddy bunting (Emberiza rutila). It obviously shows left-side dominance in controlling double syllables, principal frequency (PF) and increasing sound intensity of the evoked calls. Meanwhile, the complex-type control pattern can produce complex calls with multisyllable, and also shows significant left-side dominance in controlling the number of syllables, tone changing and sound intensity. These indicate that left-side HVC controls higher frequency and complicated sentence structure. The basic vocal center, dorsomedial nucleus of the intercollicular complex (DM), controls the monosyllable sound in songbirds, and shows left-side dominance in controlling both the number of syllable and sound intensity. These results not only provide some direct evidence for left-side dominance in high vocal center, but also indicate that there is some internal connection between the high and basic vocal centers in songbirds. 展开更多
关键词 ruddy bunting high VOCAL center basic VOCAL center control pattern left-side dominance.
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岩黄连保育研究进展
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作者 黄彦棋 李翠 +3 位作者 雷明 张占江 肖冬 彭玉德 《热带农业科学》 2025年第3期164-170,共7页
岩黄连(Corydalis saxicola Bunting)生于岩石隙缝中,广泛分布于喀斯特地貌。岩黄连是一种对肝脏病症有特殊疗效的中药材。为了推进国家二级重点保护野生植物岩黄连资源可持续发展,提高人们科学保育的意识,笔者在分析岩黄连保育现状与... 岩黄连(Corydalis saxicola Bunting)生于岩石隙缝中,广泛分布于喀斯特地貌。岩黄连是一种对肝脏病症有特殊疗效的中药材。为了推进国家二级重点保护野生植物岩黄连资源可持续发展,提高人们科学保育的意识,笔者在分析岩黄连保育现状与问题的基础上,对其保育技术方法与应用、进展与突破展开综述。结合保育成果,分析带来的经济效益、社会效益、生态效益;阐述当前保育存在的挑战与限制,展望保育研究热点,将岩黄连保育融入生态建设中。 展开更多
关键词 岩黄连 保育意义 保育现状 保育措施
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岩黄连的繁育与分子生物学研究进展
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作者 张怡彬 郭伦发 +2 位作者 秦洪波 王新桂 潘燕林 《中国野生植物资源》 2025年第11期89-95,共7页
岩黄连是我国西南岩溶地区特有的珍稀植物,是广西传统壮药资源。受生境脆弱、种群更新受限和人为采挖等多因素影响,其野生资源濒临枯竭,资源保护与利用的矛盾日益突出,亟待关注和解决。本文对岩黄连种苗繁育、人工栽培和分子生物学研究... 岩黄连是我国西南岩溶地区特有的珍稀植物,是广西传统壮药资源。受生境脆弱、种群更新受限和人为采挖等多因素影响,其野生资源濒临枯竭,资源保护与利用的矛盾日益突出,亟待关注和解决。本文对岩黄连种苗繁育、人工栽培和分子生物学研究等方面进行了系统综述,总结了种苗繁育和人工栽培关键环节的优选方案。此外,本文还分析了现有研究的不足之处,提出未来研究的重点方向,为岩黄连濒危机制、优良种质选育、功能基因挖掘、分子育种、资源保护与利用等方面的深入研究提供更广阔的思路和理论参考。 展开更多
关键词 岩黄连 种子萌发 组织培养 栽培研究 分子生物学
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岩黄连化学成分及其对肝病作用机制研究进展
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作者 温钊迪 黄丽容 +2 位作者 李翠 雷明 张占江 《亚太传统医药》 2025年第6期239-247,共9页
岩黄连是中国西南地区的一种传统民间药材,具有清热止痛、祛毒消炎、健胃止血等功效。岩黄连主要化学成分为生物碱类、甾体类、黄酮类、三萜类和烷烃类等,其中生物碱类是岩黄连中的主要药效成分。岩黄连防治肝脏疾病的作用尤为突出,具... 岩黄连是中国西南地区的一种传统民间药材,具有清热止痛、祛毒消炎、健胃止血等功效。岩黄连主要化学成分为生物碱类、甾体类、黄酮类、三萜类和烷烃类等,其中生物碱类是岩黄连中的主要药效成分。岩黄连防治肝脏疾病的作用尤为突出,具体表现如下:岩黄连通过抗乙肝病毒调节肝炎动物中转氨酶水平、减轻肝细胞变性;岩黄连通过下调PI3K/AKT/mTOR信号通路抑制肝癌细胞增殖和生长;岩黄连通过调节抗氧化应激、抗炎、诱导细胞凋亡、改善氨基酸代谢和调节脂质代谢等抑制肝脏细胞纤维化;岩黄连通过增加肝细胞抗氧化、改善肝细胞膜通透性、调节脂质代谢等保护肝组织病变,减轻肝细胞损伤;岩黄连通过激活AMPK、PI3K和Akt等信号缓解肝细胞炎症、减少肝脏脂质积累,保护肝脏功能。对岩黄连化学成分及其防治肝病的作用机制进行全面综述,为岩黄连的临床应用和未来的研究开发提供参考。 展开更多
关键词 岩黄连 民族药 生物碱 肝脏疾病 药理作用机制
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岩黄连生物碱类化学成分及其抗肝癌活性研究
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作者 张晓 秦国飞 +3 位作者 朱峰 霍宗庆 关永霞 张贵民 《中药材》 北大核心 2025年第1期91-99,共9页
目的:研究岩黄连的生物碱类化学成分及抗肝癌活性。方法:采用硅胶柱层析、C18反相柱层析、Sephadex LH-20葡聚糖凝胶及半制备型高效液相等色谱技术对岩黄连进行分离纯化,根据理化性质结合波谱数据鉴定化合物结构,并运用CCK-8法对化合物... 目的:研究岩黄连的生物碱类化学成分及抗肝癌活性。方法:采用硅胶柱层析、C18反相柱层析、Sephadex LH-20葡聚糖凝胶及半制备型高效液相等色谱技术对岩黄连进行分离纯化,根据理化性质结合波谱数据鉴定化合物结构,并运用CCK-8法对化合物进行体外抗肝癌活性评价。结果:从岩黄连中分离得到23个化合物,分别鉴定为:16-hydroxy-17-methoxy-5,7-dioxa-1-azapentacyclo[11.8.0.03,11.04,8.014,19]henicosa-3(11),4(8),9,12,14,16,18-heptaen-2-one(1)、13,14-dihydro-2,3-dimethoxy-13-methyl-9,10-methylenedioxyberbine-8-one(2)、8-氧化表小檗碱(3)、polycarpine(4)、(8R,13R,14R)-8-甲氧基羰基甲基岩黄连碱(5)、蛇果黄堇碱(6)、(±)-阿朴卡维汀(7)、(+)-thalictrifoline(8)、氢化小檗碱(9)、左旋四氢巴马汀(10)、(+)-碎叶紫堇碱(11)、四氢非洲防己胺(12)、(±)-卡维汀(13)、8-丙酮基-二氢白屈菜红碱(14)、6-丙酮基-5,6-二氢血根碱(15)、8-甲氧基去甲白屈菜红碱(16)、去甲白屈菜红碱(17)、去甲血根碱(18)、二氢白屈菜红碱(19)、二氢血根碱(20)、9S-alkterlactone B(21)、紫堇定(22)、橙黄胡椒酰胺(23)。化合物8、19和20对HuH7肿瘤细胞株显示较强的体外抑制活性,IC50分别为5.62、16.10、10.15μmol/L。结论:其中,化合物1、2为新天然产物,化合物3~5、17、18、21、23为首次从该植物中分离得到,化合物8、19和20表现出较强的体外抗肝癌活性。 展开更多
关键词 岩黄连 生物碱 原小檗碱类 小檗碱类 抗肝癌活性
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1,3-二硫环已烷系列衍生物的合成及表征 被引量:8
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作者 胡卫兵 刘红霞 +1 位作者 余爱农 陈雄波 《应用化学》 CAS CSCD 北大核心 2005年第3期340-342,共3页
Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction o f 7 aldehydes(or ketones) with Bunte′s salt prepared from 1,3-dichloroprop ane and sodium thiosulfate. The procedure has the feature of easi... Seven derivatives of 1,3-dithiocyclohexane were prepared via the reaction o f 7 aldehydes(or ketones) with Bunte′s salt prepared from 1,3-dichloroprop ane and sodium thiosulfate. The procedure has the feature of easier operation, s horter reaction time and higher yield. The yields of seven derivatives of 1,3- dithiocyclohexane are between 58% and 75%. The optimum molar ratio of 1,3-d ichloropropane to sodium thiosulfate was 1∶1 in the preparati on of Bunte′s salt. The structures of seven derivatives were characterized by m eans of IR, 1H NMR, MS. 展开更多
关键词 bunteSalt法 合成 二硫环己烷 香料 表征
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黄胸鹀COⅠ基因遗传多样性分析
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作者 陈俊杰 张俊 +3 位作者 何小云 卢思励 张佳欢 周璨林 《四川农业大学学报》 北大核心 2025年第5期1331-1340,共10页
【目的】探究黄胸鹀(Emberiza aureola)的遗传多样性,利用线粒体COⅠ基因对黄胸鹀的遗传多样性水平进行研究。【方法】利用线粒体细胞色素c氧化酶亚单位Ⅰ(COⅠ)基因,对黄胸鹀的遗传多样性水平进行分析。选取24个黄胸鹀的肌肉样本,利用... 【目的】探究黄胸鹀(Emberiza aureola)的遗传多样性,利用线粒体COⅠ基因对黄胸鹀的遗传多样性水平进行研究。【方法】利用线粒体细胞色素c氧化酶亚单位Ⅰ(COⅠ)基因,对黄胸鹀的遗传多样性水平进行分析。选取24个黄胸鹀的肌肉样本,利用DNA提取试剂盒提取基因组DNA,并对线粒体COⅠ基因进行PCR扩增和测序。通过MEGA11软件对测序结果进行多重序列比对,计算碱基组成和单倍型间的遗传距离,并构建系统发育树。利用NETWORK10.2软件绘制单倍型网络关系图,分析单倍型之间的进化关系。此外,使用Arlequin3.5软件评估单倍型多样性、核苷酸多样性及平均核苷酸变异数,以全面了解黄胸鹀的遗传多样性水平。【结果】黄胸鹀COⅠ基因序列长度为675 bp,碱基A、T、C、G的含量分别为25.25%、23.71%、32.53%、18.51%,显示出不明显的CG偏倚性。在31条序列当中共检测到77个碱基变异位点和23个单倍型,表明黄胸鹀具有较高的遗传变异水平。单倍型多样性为0.9763±0.0163,核苷酸多样性为0.018192±0.009395,平均核苷酸变异数为12.279570±5.700130,这些指标均表明黄胸鹀种群具有较高的遗传多样性。系统发育树分析显示,黄胸鹀单倍型分为两个主要支系(Clade A和Clade B),其中Clade A包含17个单倍型,Clade B包含6个单倍型。单倍型网络图显示,Hap5单倍型处于中心位置,表明其为黄胸鹀的原始单倍型,且通过突变产生了多个其他单倍型。此外,Hap1、Hap2、Hap4、Hap9、Hap16和Hap20这6个单倍型与其他单倍型的平均遗传距离均大于0.03,表现出一定的遗传分化水平。【结论】黄胸鹀表现出较高的单倍型多样性和核苷酸多样性,表明其种群遗传多样性水平较高,近亲繁殖水平较低。尽管黄胸鹀种群数量急剧下降,但仍具有较强的恢复潜力。 展开更多
关键词 黄胸鹀 脱氧核糖核酸 线粒体COⅠ基因 遗传多样性
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1,3-二硫环戊烷系列化合物的合成新方法 被引量:2
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作者 冯驸 余爱农 胡卫兵 《中国调味品》 CAS 北大核心 2010年第4期115-116,共2页
用Bunte Salt法,以1,2-二氯乙烷和一系列的醛(酮)为原料,乙醇为溶剂,合成了5个环戊烷硫醚类香料(a~e),结果表明,该方法具有操作简单,产率高,环境污染小等优点。用IR,1HNMR和MS证实了目标化合物结构。
关键词 1 2-二氯乙烷 合成 香料 bunte Salt法 反应
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