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Exploration and Practice of the"One-Student-Two-Tutors"Community through Integrating"1+3 Teaching Resources"into Undergraduate Experimental Teaching
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作者 Yongming YANG Dongfang TU +6 位作者 Yan YU Shengwei YAO Wei ZHANG Shuangyuan WANG Pengyun DUAN Weiyu NI Wencui LIU 《Asian Agricultural Research》 2024年第11期49-53,共5页
This study closely follows the spirit of the first class undergraduate education action plan(2021-2025)of University of Shanghai for Science and Technology,combines with the national first-class undergraduate professi... This study closely follows the spirit of the first class undergraduate education action plan(2021-2025)of University of Shanghai for Science and Technology,combines with the national first-class undergraduate professional training plan of mechanical design and manufacturing and automation,and carries out the exploration and practice of"1+3 teaching resources"integrating into the"One-Student-Two-Tutors"community of undergraduate experimental teaching.On the basis of creating a good learning environment and creating an excellent learning platform,this paper studies the undergraduate experimental teaching of the trinity of"theoretical courses+experimental courses+innovation and entrepreneurship activities,discipline competitions,and scientific research project activities".This study has a certain reference value for colleges and universities to cultivate outstanding engineering talents with happy learning attitude,scientific research interest,practical ability and innovative ability. 展开更多
关键词 "1+3 teaching resources" "One-Student-Two-Tutors"community Undergraduate experimental teaching
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Discussion on the Construction of Green Agriculture “3+1” Industry System Using Fenlong Activated Resources 被引量:8
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作者 韦本辉 《Agricultural Science & Technology》 CAS 2017年第2期380-384,共5页
The newly invented farming method, Fenlong technology, uses self-propelled powder-ridging mechanical screw-type drill for the deep-cultivation and deep tillage of soil, and it can enhance the double tillering depth th... The newly invented farming method, Fenlong technology, uses self-propelled powder-ridging mechanical screw-type drill for the deep-cultivation and deep tillage of soil, and it can enhance the double tillering depth than the conventional tillage. Moreover, the tilth soil is uniform in size and in small, broken bits and loose. It expands the new soil "four warehouses" (namely soil nutrient warehouse, water warehouse, oxygen warehouse and microbial warehouse), and under the conditions of "three no increase" in chemical fertilizer and pesticide, irrigation water and labor input, various crops show a increase of 10%-30% in yield (average increase by 25.48% in the 23 rice, wheat and corn planting areas of several provinces), 5% in quality, and 1 time in water retention. And the sustainable production-increasing ef- fect lasts 2-3 years after once Fenlong tillage, with the comparative efficiency reaching about 20%. It is suggested using Fenlong to activate the arable land, saline land grassland and rivers resources, so as to drive the construction of green agriculture "3+1" industrial system, which can promote the realization of the increases in available agricultural resource stock, quality food resource stock and available water resource stock in China and even in the world, realize the "two responses" to ecological environment deterioration and climate warming, and achieve the harmonious coexistence of human beings and nature. 展开更多
关键词 Fenlong Activated resources 3+1" system Green ECOLOGY
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硫酸铵强化石膏溶解矿化制备高纯CaCO_(3)
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作者 刘妍汝 钟山 +4 位作者 唐思扬 杨柯 宋磊 李红娇 梁斌 《洁净煤技术》 CAS CSCD 北大核心 2024年第4期137-145,共9页
近年来,利用固废石膏矿化CO_(2)联产CaCO_(3)及硫酸铵工艺技术受到广泛关注,然而由于固废石膏成分复杂,分离纯化困难,成本与矿化产品品质难以兼顾导致其无法大规模工业化利用。为此,以硫酸钙及磷石膏为原料,提出以石膏矿化液相产物硫酸... 近年来,利用固废石膏矿化CO_(2)联产CaCO_(3)及硫酸铵工艺技术受到广泛关注,然而由于固废石膏成分复杂,分离纯化困难,成本与矿化产品品质难以兼顾导致其无法大规模工业化利用。为此,以硫酸钙及磷石膏为原料,提出以石膏矿化液相产物硫酸铵溶液强化硫酸钙溶解浸出,液固分离后再进行矿化的间接矿化工艺。试验研究了溶解强化过程中硫酸铵浓度及溶解浸出时间对硫酸钙溶解特性的影响,以及矿化过程中氨水浓度、温度、矿化反应时间等因素对矿化过程和矿化产物的影响。确定了优化的溶解与矿化工艺条件,基于此,进一步研究磷石膏的间接矿化过程,结果表明,与直接矿化相比,间接矿化可使CaCO_(3)产品纯度由82.2%提高至98.6%,且产品粒度D_(50)由22.00μm降至10.98μm。间接矿化工艺可有效强化石膏溶解浸出过程,避免引入外加介质,并制备高纯度轻质CaCO_(3),相关研究可为固废石膏矿化CO_(2)技术的经济应用提供基础支持。 展开更多
关键词 CO_(2)矿化 溶解强化 CaCO_(3) 石膏固废 资源化利用
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SAR-3——a resource of diploid true breeding hybrid rice 被引量:6
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作者 ZHOU Kaida, WANG Xudong, Wu Xianjun, YAN Zhibing. and ZHOU Xaohe, Rice Res Inst of Sichuan AgriUniv , Wenjiangg 611130, China 《Chinese Rice Research Newsletter》 1997年第4期1-1,共1页
In 1988, we found strain 9003 from compositehybridization of indica and japonica. 9003 pos-sesses characteristics of twin seedlings withfrequency of 15-20% of the investigated popu-lation. The highest frequency was 45... In 1988, we found strain 9003 from compositehybridization of indica and japonica. 9003 pos-sesses characteristics of twin seedlings withfrequency of 15-20% of the investigated popu-lation. The highest frequency was 45.68%.Afterwards, we discovered that some twinseedlings had variabilities in chromosome set.As to a pair of twin plants, it may be 2n-1n,2n-3n, 3n-3n or 1n-1n. The changes in chro-mosome set also occurred in the plants devel-oped from mono-embryo seeds. All of thesevariants nearly account for 1% in our con-trolled experiment. We named the triploidplants SAR-3 and found that SAR-3 could be aresource of diploid true breeding hybrid rice. 展开更多
关键词 SAR-3 a resource of diploid true breeding hybrid rice
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CO_(2) mineralization by typical industrial solid wastes for preparing ultrafine CaCO_(3): A review
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作者 Run Xu Fuxia Zhu +8 位作者 Liang Zou Shuqing Wang Yanfang Liu Jili Hou Chenghao Li Kuntong Song Lingzhao Kong Longpeng Cui Zhiqiang Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1679-1697,共19页
Mineral carbonation is a promising CO_(2) sequestration strategy that can utilize industrial wastes to convert CO_(2) into high-value CaCO_(3).This review summarizes the advancements in CO_(2) mineralization using typ... Mineral carbonation is a promising CO_(2) sequestration strategy that can utilize industrial wastes to convert CO_(2) into high-value CaCO_(3).This review summarizes the advancements in CO_(2) mineralization using typical industrial wastes to prepare ultrafine CaCO_(3).This work surveys the mechanisms of CO_(2) mineralization using these wastes and its capacities to synthesize CaCO_(3),evaluates the effects of carbonation pathways and operating parameters on the preparation of CaCO_(3),analyzes the current industrial application status and economics of this technology.Due to the large amount of impurities in solid wastes,the purity of CaCO_(3) prepared by indirect methods is greater than that prepared by direct methods.Crystalline CaCO_(3) includes three polymorphs.The polymorph of CaCO_(3) synthesized by carbonation process is determined the combined effects of various factors.These parameters essentially impact the nucleation and growth of CaCO_(3) by altering the CO_(2) supersaturation in the reaction system and the surface energy of CaCO_(3) grains.Increasing the initial pH of the solution and the CO_(2)flow rate favors the formation of vaterite,but calcite is formed under excessively high pH.Vaterite formation is favored at lower temperatures and residence time.With increased temperature and prolonged residence time,it passes through aragonite metastable phase and eventually transforms into calcite.Moreover,polymorph modifiers can decrease the surface energy of CaCO_(3) grains,facilitating the synthesis of vaterite.However,the large-scale application of this technology still faces many problems,including high costs,high energy consumption,low calcium leaching rate,low carbonation efficiency,and low product yield.Therefore,it is necessary to investigate ways to accelerate carbonation,optimize operating parameters,develop cost-effective agents,and understand the kinetics of CaCO_(3) nucleation and crystallization to obtain products with specific crystal forms.Furthermore,more studies on life cycle assessment(LCA)should be conducted to fully confirm the feasibility of the developed technologies. 展开更多
关键词 Industrial solid wastes resource utilization Mineral carbonation Ultrafine CaCO_(3) Carbon emission reduction
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3D Modeling Quantitative Evaluation for the Underground Space Resources in Beijing City
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作者 Yi Tian,Jianping Chen,Limei Wang School of Land Resources and Technology,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期283-284,共2页
Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models... Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models to establish a practicable underground space resources quantitative evaluation system.It sets up 展开更多
关键词 CITY UNDERGROUND SPACE resourceS QUANTITATIVE evaluation 3D MODELING
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Application of“3S”Technology in Land Resource Management
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作者 Jianshi Xiao 《Journal of World Architecture》 2020年第5期4-6,共3页
Land is the foundation of human existence,and it is also an important prerequisite and foundation for social construction and economic development.However,with the continuing construction and development of society an... Land is the foundation of human existence,and it is also an important prerequisite and foundation for social construction and economic development.However,with the continuing construction and development of society and economy,a large number of trees have been felled,and the level of land desertification has been increasing.Therefore,it is very necessary to pay attention to strengthening land resource management.The application of“3S”technology in land resource management not only solves some problems in land resources,but also promotes the development of China’s economy.The author conducted research and analysis on“3S”technology,and put forward an effective strategy for the application of“3S”technology in land resource management,hoping to help the smooth progress of land resource management activities. 展开更多
关键词 3S”technology Land resources Application strategy
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与辣椒抗TMV L^(3)基因连锁的分子标记的筛选及种质资源抗TMV鉴定 被引量:1
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作者 陈灵芝 张茹 +1 位作者 王兰兰 高彦萍 《西北农业学报》 CAS CSCD 北大核心 2023年第4期585-592,共8页
以含抗辣椒TMV的L^(3)基因的材料L15为基础,利用与L^(3)基因连锁的3个分子标记189D23MF、PMFR11和PMFR21对种质资源进行鉴定.对L15、3份感病材料H8/H9/H11×L15 F_(1)、46份辣椒种质资源进行室内人工TMV接种并对其进行表型抗性鉴定... 以含抗辣椒TMV的L^(3)基因的材料L15为基础,利用与L^(3)基因连锁的3个分子标记189D23MF、PMFR11和PMFR21对种质资源进行鉴定.对L15、3份感病材料H8/H9/H11×L15 F_(1)、46份辣椒种质资源进行室内人工TMV接种并对其进行表型抗性鉴定和RT-PCR检测.对筛选出的标记在F_(1)及BC_(1)P_(1)群体中进行验证.结果表明:分子标记189D23MF在L15和12份辣椒种质上均未扩增出条带;SCAR标记PMFR11在L15和46份辣椒种质上呈现共显性分离,SCAR标记PMFR21为显性标记.通过室内人工接种鉴定方式,2份材料L15、H11×L15表现为高抗.H9×L15表现为抗,H8×L15及5份材料A1、A35、A39、A55、L16表现为中抗,11份材料表现为感病,30份材料表现为高感.在F1及BC1P1群体中PCR扩增结果表明SCAR标记PMFR21可用于辣椒抗TMV分子标记辅助选择. 展开更多
关键词 辣椒 L^(3)基因 分子标记 种质资源 TMV
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东北地区大豆种质资源对SCN3抗性表型评价 被引量:1
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作者 周长军 吴耀坤 +4 位作者 于吉东 刘冰 李建英 马兰 陈刚 《黑龙江农业科学》 2023年第7期47-51,共5页
为明确东北地区种质资源对大豆胞囊线虫3号生理小种(SCN3)抗性,以东北地区常用作亲本的620份大豆品种(系)为材料,经2020-2021年SCN3号生理小种田间病圃及室内盆栽接种鉴定。结果表明,2020年田间病圃鉴定对SCN3号生理小种表现中抗以上品... 为明确东北地区种质资源对大豆胞囊线虫3号生理小种(SCN3)抗性,以东北地区常用作亲本的620份大豆品种(系)为材料,经2020-2021年SCN3号生理小种田间病圃及室内盆栽接种鉴定。结果表明,2020年田间病圃鉴定对SCN3号生理小种表现中抗以上品种(系)有30份,抗病种质仅占鉴定种质总数的4.84%,2021年对这30份中抗以上材料进行室内盆栽接种鉴定,除白农9号、嫩丰15外,其余品种(系)抗性级别鉴定与田间病圃结果一致。其中农庆豆24、农庆豆28、齐农5号、丰豆1号等13个中抗以上品种可在大豆胞囊线虫病发区直接应用,MN0902CN、MN1701CN、中品03-5373、中品03-5297等9份抗病品系可用作种质资源创新抗病亲本,其他8份中抗品系可用作拓宽抗性基因遗传基础的复合杂交亲本。 展开更多
关键词 种质资源 大豆胞囊线虫3号生理小种 抗性评价
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SIMULATION AND APPLICATION OF THREE_DIMENSIONAL MIGRATION_ACCUMULATION OF OIL RESOURCES 被引量:3
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作者 袁益让 赵卫东 +1 位作者 程爱杰 韩玉笈 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第9期999-1009,共11页
Numerical simulation of oil migration and accumulation is to describe the history of oil migration and accumulation in basin evolution. It is of great value in the exploration of oil resources and their rational evalu... Numerical simulation of oil migration and accumulation is to describe the history of oil migration and accumulation in basin evolution. It is of great value in the exploration of oil resources and their rational evaluation. In this paper, from such actual conditions as the effects of mechanics of fluids in porous media and 3-dimensional geology characteristics, a kind of modified method of second order splitting-up implicit interactive scheme is pur forward. For the famous hydraulic experiment of secondary migration-accumulation, the numerical simulation test has been done, and both the computational and experimental results are basically identical. For the actual problem of Dongying hollow of Shengli Petroleum Oil Field, the numerical simulation test and the actual conditions are basically coincident. Thus the well-known problem has been solved. 展开更多
关键词 mechanics of immiscible flow 3-dimensional migration-accumulation of oil resources splitting-up numerical simulation Dongying hollow
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Evaluation of urban underground space resources using a negative list method: Taking Xi'an City as an example in China 被引量:9
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作者 Mao-sheng Zhang Hua-qi Wang +3 位作者 Ying Dong Lin Li Ping-ping Sun Ge Zhang 《China Geology》 2020年第1期124-136,共13页
Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city env... Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city environment,build livable city and increase the capacity of the city.Based on the analysis of existing evaluation methods and their problems,a method for evaluating underground space resources based on a negative list of adverse factors affecting underground space development is proposed,to be primarily used in urban planning stages.A list of the adverse factors is established,including limiting factors,constraining factors and influencing factors.Taking Xi'an as an example,using a geographical information system platform,a negative list of adverse factors for the underground space resources in Xi'an City are evaluated,and preventive measures are proposed.Natural resources,exploitable resources,and the potential growth of exploitable underground space resources are evaluated.Underground space assessment in the different development stages of the city,collaborative utilization and safety evaluation for multiple subsurface resources,environmental impact and assessment,as well as evaluation methods based on big data and intelligent optimization algorithms are all discussed with the aim of serving city planning and construction. 展开更多
关键词 Urban geology Negative list Natural resources for underground space Exploitable resources for underground space 3D geological structure model GIS platform Urban geological survey engineering Xi'an City Shaanxi Province China
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灌溉和种植方式对双季稻田NH3挥发和N2O排放的影响 被引量:1
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作者 刘现波 万岚 +5 位作者 时红 才硕 王廷金 王海媛 万绍媛 程婕 《水利水电技术(中英文)》 北大核心 2023年第12期35-50,共16页
【目的】探究种植和灌溉方式对双季稻全生育期水分利用效率以及氮素气态损失的影响。【方法】以双季稻田为研究对象,在江西省灌溉试验中心站研究基地开展大田试验,设置手工栽插(HT)、机械插秧(MT)、抛秧(ST)、直播(DS)四种种植方式,淹... 【目的】探究种植和灌溉方式对双季稻全生育期水分利用效率以及氮素气态损失的影响。【方法】以双季稻田为研究对象,在江西省灌溉试验中心站研究基地开展大田试验,设置手工栽插(HT)、机械插秧(MT)、抛秧(ST)、直播(DS)四种种植方式,淹水灌溉(FI)和间歇灌溉(II)两种灌溉方式,分析不同种植和灌溉方式对双季稻全生育期水分利用效率以及秧田期、本田期NH3挥发及N2O排放的影响,提出NH3挥发和N2O排放的主要时期。【结果】结果表明:(1)与传统淹水灌溉相比,间歇灌溉下水稻产量略有增加,不同种植方式间产量差异显著,HT最高,DS最低。(2)同一种植方式下,间歇灌溉下N2O排放量较淹水灌溉增加约7.9%~16.4%,同一灌溉方式下,早稻N2O损失量大小为DS>MT>HT>ST,晚稻为DS>HT>MT>ST,早、晚稻N2O排放主要发生在分蘖期、拔节孕穗期、成熟期,3个生育阶段N2O损失量占比超过70%,而育秧期MT、ST占比不到1.5%,HT为6.4%。(3)同一种植方式下,早、晚稻NH3挥发损失量淹水灌溉比间歇灌溉增加了3.0%~30.8%,同一灌溉方式下,DS相比移栽稻显著增加NH3挥发(P<0.05),HT、MT、ST之间无显著差异,NH3挥发峰值均在施肥后3 d内出现,且主要发生在苗期、分蘖期、拔节孕穗期3个时期,其NH3挥发损失量之和占整个生育期NH3挥发损失量80%以上,育秧期MT、ST占比不到2%,HT达4.2%。【结论】在不同种植方式下,间歇灌溉方式会提高双季稻产量和N2O排放,但会降低NH3挥发,从早、晚稻生育阶段来看,N2O损失主要发生在生育前期和后期,NH3挥发损失主要发生在生育前中期,且育秧期NH3挥发和N2O排放占比较低,DS在显著降低产量的同时带来了更高的N2O排放和NH3挥发。 展开更多
关键词 双季稻 种植方式 灌溉方式 N2O排放 NH3挥发 水资源 影响因素
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Nb_(2)O_(5)-Al_(2)O_(3)-MgO-Na_(2)O-CaO-SiO_(2)体系相平衡研究
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作者 陈昌 任国兴 +2 位作者 韩文生 冉孟杰 陈雯 《有色金属(冶炼部分)》 CAS 北大核心 2023年第10期55-63,共9页
为揭示Nb_(2)O_(5)-Al_(2)O_(3)-MgO-Na_(2)O-CaO-SiO_(2)多元含铌炉渣体系中的铌矿物的定向结晶规律,采用高温相平衡—冷淬—SEM-EDS/XRD/EMPA试验方法,考察了温度、钙硅比(CaO/SiO_(2))、Nb_(2)O_(5)含量等因素对炉渣相平衡关系的影响... 为揭示Nb_(2)O_(5)-Al_(2)O_(3)-MgO-Na_(2)O-CaO-SiO_(2)多元含铌炉渣体系中的铌矿物的定向结晶规律,采用高温相平衡—冷淬—SEM-EDS/XRD/EMPA试验方法,考察了温度、钙硅比(CaO/SiO_(2))、Nb_(2)O_(5)含量等因素对炉渣相平衡关系的影响,并构建了含铌矿物结晶析出的优势相图。结果表明:铌的结晶矿物主要有三种,分别为Ca_(2)Nb_(2)O_(7)、Ca_((14-x))Nb_((2+x))Si_(8)O_((35+1.5x))和3CaO·MgO·Nb_(2)O_(5);铌先富集于液相,相较于脉石组分,含铌固相为后析出相;CaO/SiO_(2)增加会使含铌固相优势区间发生从Ca_(2)Nb_(2)O_(7)相到Ca_((14-x))Nb_((2+x))Si_(8)O_((35+1.5x))相、再到3CaO·MgO·Nb_(2)O_(5)相的转变。Ca_(2)Nb_(2)O_(7)相的优势析晶区间为:温度1050~1200℃,C/S=0.8~1.2。Nb_(2)O_(5)在Ca_((14-x))Nb_((2+x))Si_(8)O_((35+1.5x))相中的嵌布质量浓度在18.5%~19.5%。 展开更多
关键词 铌资源 相平衡 矿相转化 Nb_(2)O_(5)-Al_(2)O_(3)-MgO-Na_(2)O-CaO-SiO_(2)
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基于铜渣制备γ-Fe_(2)O_(3)及其光催化-降解性能研究 被引量:2
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作者 蒋周 李鹏 +1 位作者 闫炳基 国宏伟 《中国有色冶金》 CAS 北大核心 2023年第4期88-96,共9页
我国铜渣年产量已超过2000万t,铜渣中的主要矿相成分为铁橄榄石和磁性氧化铁,铁含量超过30%,由于铁橄榄石有较高的热力学稳定性,目前铜渣中铁的回收方式需要消耗大量能量,成本较高。磁赤铁矿(γ-Fe_(2)O_(3))是一种具有阳离子空位的亚... 我国铜渣年产量已超过2000万t,铜渣中的主要矿相成分为铁橄榄石和磁性氧化铁,铁含量超过30%,由于铁橄榄石有较高的热力学稳定性,目前铜渣中铁的回收方式需要消耗大量能量,成本较高。磁赤铁矿(γ-Fe_(2)O_(3))是一种具有阳离子空位的亚稳磁性材料,在污水处理、生物医学和催化领域具有广泛的应用。本文以铜渣为原料,通过低温碱熔-水解-煅烧工艺获得了具有较高纯度的γ-Fe_(2)O_(3)。试验结果表明,经550℃焙烧可将铜渣中的含铁矿相(铁橄榄石,磁铁矿)转化为α-NaFeO_(2)前驱体;α-NaFeO_(2)前驱体水解-煅烧后可获得较高纯度的γ-Fe_(2)O_(3),该γ-Fe_(2)O_(3)禁带宽度为2.20 eV,在可见光范围内具有良好的光催化活性;所制备γ-Fe_(2)O_(3)材料的比表面积为9.354 m^(2)/g,平均孔径为14.88 nm,孔容为0.0348 cm^(3)/g,饱和磁化强度为19.13 emu/g;在室温环境下对亚甲基蓝溶液开展光催化-降解性能研究,光降解过程符合拟一阶动力学模型,反应速率常数K为1.29×10^(-2)min^(-1)(20 mg/L);添加少量H_(2)O_(2)能够提高光降解效率;γ-Fe_(2)O_(3)材料由于具有顺磁性,光降解结束后可实现固液相分离,在多次循环光降解性能测试中表现出优异的稳定性。该工艺采用低温碱熔,能量消耗低,为铜渣的资源化利用提供了一种新途径。 展开更多
关键词 铜渣 铁资源利用 γ-Fe_(2)O_(3) 亚稳磁性材料 顺磁性 光催化 亚甲基蓝 回收成本
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3-蒈烯资源及其生物活性应用研究进展 被引量:43
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作者 何丽芝 王婧 +2 位作者 赵振东 陈玉湘 古研 《林产化学与工业》 EI CAS CSCD 北大核心 2011年第3期122-126,共5页
综述了3-蒈烯的主要资源及其生物活性应用。3-蒈烯的主要资源为松科植物和一些中草药植物的挥发性天然精油,重要的有长叶松、欧洲赤松、思茅松、白胡椒、九里香和圆叶当归等,一般通过水蒸气蒸馏的方式获得,并以精馏方式进行分离和提纯... 综述了3-蒈烯的主要资源及其生物活性应用。3-蒈烯的主要资源为松科植物和一些中草药植物的挥发性天然精油,重要的有长叶松、欧洲赤松、思茅松、白胡椒、九里香和圆叶当归等,一般通过水蒸气蒸馏的方式获得,并以精馏方式进行分离和提纯。3-蒈烯作为中草药中的活性成分可直接利用植物本身,也可以天然精油的形式在医药、农药、化妆品等行业作为中间体或者配方原料使用。 展开更多
关键词 3-蒈烯 天然资源 生物活性应用
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猪LPL基因内含子3的克隆、测序及多态性研究 被引量:10
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作者 张振波 雷明刚 +1 位作者 邓昌彦 熊远著 《畜牧兽医学报》 CAS CSCD 北大核心 2005年第6期627-630,共4页
Lipoprotein lipase (LPL) gene is a multifunctional protein, playing a major role in the hydrolysis of triglycerides in chylomicrons and very low density lipoproteins (VLDL). According to cDNA of Landrace breed (GenBan... Lipoprotein lipase (LPL) gene is a multifunctional protein, playing a major role in the hydrolysis of triglycerides in chylomicrons and very low density lipoproteins (VLDL). According to cDNA of Landrace breed (GenBank accession: X62984), a pair of primers was designed for amplification of intron 3. Sequencing analysis indicated that a G1200A exits in Large White breed by cloning and sequencing. The mutation can be detected by PCR-EcoT22I-RFLP. Polymorphism analysis in a resource family showed that significant difference exits in carcass traits. Pigs with AA genotype had more 6th-7th rib fat thickness (13%,P< 0.05), thorax-waist-fat thickness (11.7%,P=0.065 3), buttock fat thickness (13.1%,P=0.073 0) and average fat thickness (10.4%,P=0.050 3) than pigs with BB genotype. LPL gene showed mainly in the pattern of additive effect and all the dominant effect were not significant. The value of additive effect of 6th-7th rib fat thickness, buttock fat thickness and average fat thickness was -0.17±0.07(P< 0.05),-0.12±0.06( P< 0.05),-0.12±0.06(P< 0.05),respectively. The allelic frequency is significantly different between indigenous Chinese breeds and European breeds. 展开更多
关键词 多态性研究 内含子 L基因 极低密度脂蛋白 克隆 测序 三酰甘油 脂蛋白脂酶 LPL 脂肪组织 代谢障碍 水解酶 脂肪酸
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四川茶树品种资源中EGCG3″Me研究 被引量:4
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作者 李建华 齐桂年 +1 位作者 陈盛相 朱明珠 《食品工业科技》 CAS CSCD 北大核心 2015年第16期108-113,共6页
采用高效液相色谱法(HPLC)对四川70份茶树品种资源新梢中(-)-表没食子儿茶素-3-O(3-O-甲基)没食子酸酯(EGCG3″Me)含量进行分析,发现3份茶树品种资源富含EGCG3″Me(含量>10 mg/g),即蜀茶5号、金观音、城西11号。对蜀茶5号新梢季节及... 采用高效液相色谱法(HPLC)对四川70份茶树品种资源新梢中(-)-表没食子儿茶素-3-O(3-O-甲基)没食子酸酯(EGCG3″Me)含量进行分析,发现3份茶树品种资源富含EGCG3″Me(含量>10 mg/g),即蜀茶5号、金观音、城西11号。对蜀茶5号新梢季节及叶位变化规律研究,发现春、夏、秋三季,随着新梢叶片成熟,EGCG3″Me含量均先增加后降低;同等叶位相比,EGCG3″Me含量均呈递增趋势;含量最高的叶位为秋梢第二叶,秋梢第一叶至第四叶均超过10 mg/g。以蜀茶5号秋梢加工成4种茶类,发现绿茶、黄茶中EGCG3″Me含量最高,与鲜叶相当,其次为青茶,而红茶中未检出,且萎凋显著增加其含量。建议四川富含EGCG3″Me茶叶将秋梢一芽二、三叶加工成绿茶或黄茶,且在加工前进行适度摊放(轻度萎凋)。 展开更多
关键词 EGCG3″Me 茶树品种资源 季节 叶位 加工
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资源3号卫星影像的植被信息提取 被引量:6
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作者 张雨 林辉 《中南林业科技大学学报》 CAS CSCD 北大核心 2014年第11期130-134,共5页
资源3号卫星(ZY-3)是我国2012年发射成功的第一颗自主民用高分辨率立体测绘卫星。在对ZY-3卫星数据精细处理基础上,分析了典型地物的光谱特征和纹理特征,构建了适合植被信息提取的ZY-3决策树模型,将研究区地类分为针叶林、阔叶林、灌木... 资源3号卫星(ZY-3)是我国2012年发射成功的第一颗自主民用高分辨率立体测绘卫星。在对ZY-3卫星数据精细处理基础上,分析了典型地物的光谱特征和纹理特征,构建了适合植被信息提取的ZY-3决策树模型,将研究区地类分为针叶林、阔叶林、灌木林、竹林、耕地、建设用地、裸露地、水体和其他地类共9种地类,开展植被信息提取和精度检验。结果表明:(1)ZY-3比较适合于森林植被信息的提取,特别是针叶林和阔叶林;(2)ZY-3数据的总体分类效果较好,精度达到了91.96%,Kappa系数0.902 9,说明根据影像的光谱特征和纹理特征,采用决策树算法选择合适的阈值提取植被信息是可行的。 展开更多
关键词 林业遥感 资源3号卫星(ZY-3) 森林植被 光谱特征 纹理特征 决策树模型 漓江流域
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陕北东部地区长2+3油层组远源砂质辫状河沉积特征 被引量:23
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作者 王建民 吴昌荣 《矿物岩石》 CAS CSCD 北大核心 2007年第4期92-97,共6页
通过地表露头与钻井剖面的观测分析综合研究,证实陕北东部地区长2+3油层组属于在泛滥平原下游发育的远源砂质辫状河沉积。沉积类型可划分出河道亚相与泛滥平原亚相等两个亚相以及河床滞留、河道砂坝、天然堤、决口扇、泛滥平原等5个可... 通过地表露头与钻井剖面的观测分析综合研究,证实陕北东部地区长2+3油层组属于在泛滥平原下游发育的远源砂质辫状河沉积。沉积类型可划分出河道亚相与泛滥平原亚相等两个亚相以及河床滞留、河道砂坝、天然堤、决口扇、泛滥平原等5个可识别的微相。河道砂坝为其沉积的主体。长3到长2期,远源砂质辫状河沉积在平面展布和剖面组合上均表现出向三角洲相区持续推进和逐步超覆的特点。远源砂质辫状河沉积在其平面相区内一般无明显的、限制性的河道表现,河道砂坝复合连片,形成大规模的砂坪或广泛分布的"叠覆泛砂体"沉积,泛滥平原发育区仅在局部有所残留;剖面组合上河道砂坝极为发育,复合迭加程度高,形成连续性和连通性良好的宽厚的复合河道砂坝砂体以及"砂包泥"的沉积组合。同时,远源砂质辫状河流的发育使得与其相邻的三角洲沉积具有了类似"辫状河三角洲"的性质和特点。 展开更多
关键词 陕北东部 长2+3油层组 远源砂质辫状河 沉积特征
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地下空间应急场景无人机信道选择实验设计
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作者 王博文 聂同 +1 位作者 和孜轩 胡文信 《实验技术与管理》 CAS 北大核心 2024年第10期109-115,共7页
近年来,地下空间灾害事故多发频发,利用全地形可灵活部署的无人机快速回传灾情数据是现代化应急管理体系建设的关键任务,电子信息等相关专业教学亟须进行面向地下空间的无人机应急通信网络实验和仿真。该文结合超图理论提出基于Q-learn... 近年来,地下空间灾害事故多发频发,利用全地形可灵活部署的无人机快速回传灾情数据是现代化应急管理体系建设的关键任务,电子信息等相关专业教学亟须进行面向地下空间的无人机应急通信网络实验和仿真。该文结合超图理论提出基于Q-learning的自适应动态信道选择算法,并利用ns-3网络仿真平台对网络环境模拟和网络性能测试进行了仿真实验设计,验证了该算法具有在高动态场景下有效提升网络平均吞吐量的能力,可为无人机应急通信网络场景化教学实践平台的建设打下坚实基础。 展开更多
关键词 地下空间应急通信 无人机通信 ns-3仿真 资源分配 Q-LEARNING
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