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Seaweeds as Biomonitoring System for Heavy Metal (HM) Accumulation and Contamination of Our Oceans
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作者 Vincent van Ginneken Evert de Vries 《American Journal of Plant Sciences》 2018年第7期1514-1530,共17页
This research manuscript reports the heavy metal accumulation in four marine seaweeds sp. 1)?Caulerpa sertlatioides (Cuba);2) Caulerpa cf. brachypus;(Bali, Indonesia);3) Undaria pinnatifida (West-Donegal, Ireland);4) ... This research manuscript reports the heavy metal accumulation in four marine seaweeds sp. 1)?Caulerpa sertlatioides (Cuba);2) Caulerpa cf. brachypus;(Bali, Indonesia);3) Undaria pinnatifida (West-Donegal, Ireland);4) Ulva lactuca (Easters-Scheldt, the Netherlands). Mechanical pressure at 10 bar of fresh seaweed fronds casu quo biomass in the laboratory delivered seaweed moisture which was analyzed by Inductively Coupled Plasma Spectroscopy (ICP)-techniques for heavy-metals = [HM], (Al, As, Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb & Zn). Three important observations were made: 1) The [HM] in the seaweed moisture is higher than in the surrounding seawater which directs to mechanism(s) of bio-accumulation;2) The accumulation factor [AF] is varying per metallic-cation with an overall trend for our four seaweeds and sampling locations for [HM] are: As & Co & Cu: 5000 - 10,000 μg/l;Ni & Zn: 3000 - 5000 μg/l;Cd: 2000 - 3000 μg/l;Cr: 1000 - 2000 μg/l;Al: 200 - 1000 μg/l;Mo & Pb & Fe: 0 - 200 μg/l range. 3) Seaweed moisture detected that [HM]: Pb & Zn & Fe—which all three could not be detected in the seawater—supports the view that seaweeds have a preference in their bio-accumulation mechanism for these three HM. Major conclusion is in general that “overall” for the macro-elements Ca, Fe, K, Mg, Mn, Na, P & S in the moisture of the four seaweed species the concentration is lower in the seaweed species, or equals the concentration, in comparison to the surrounding sea water. For the HM (Al, As, Cd, Co, Cr, Cu, Mo, Ni, Pb & Zn) the opposite is the case species and is the concentration “overall” higher in the seaweed species in comparison to the surrounding sea water. Further topics addressed include strategies of irrigation of the Sahara desert with the moisture out of seaweeds under conditions of low anthropogenic influences. 展开更多
关键词 Seaweeds Heavy Metal ACCUMULATION Ulva LACTUCA CAULERPA sertlatioides CAULERPA cf. brachypus & UNDARIA PINNATIFIDA Inductively Coupled Plasma Spectroscopy (ICP)-Techniques Al As Cd Co Cr Cu Fe Mo Ni Pb & Zn BIO-ACCUMULATION Biomonitoring Upper Tolerance Nutrient Intake Levels (ULs) Irrigation Water
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Formation conditions and accumulation characteristics of Bozhong 19-6 large condensate gas field in offshore Bohai Bay Basin 被引量:7
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作者 XU Changgui YU Haibo +1 位作者 WANG Jun LIU Xiaojian 《Petroleum Exploration and Development》 2019年第1期27-40,共14页
Based on the study of natural gas resource, low buried hill trap formation mechanism, high quality reservoir control factors and natural gas preservation conditions, the formation conditions and reservoir accumulation... Based on the study of natural gas resource, low buried hill trap formation mechanism, high quality reservoir control factors and natural gas preservation conditions, the formation conditions and reservoir accumulation characteristics of Bozhong 19-6 large condensate gas field were summarized. Large gas generation potential of multiple sets of thick humic-sapropelic source rocks in high maturity stage in Bozhong depression was the basis of large gas field formation. The multi-stage tectonic evolution since Indosinian period formed large-scale buried hill traps. The Tanlu fault activity formed multi-type reservoirs, and buried hill metamorphic rock of Archean and sand-conglomerate of Kongdian Formation were high-quality reservoirs. Thick overpressure lacustrine mudstone and weak neotectonic movement provided good preservation conditions. Bozhong 19-6 gas reservoir was a condensate gas reservoir with very high condensate oil content, and the gas origin was humic-sapropelic and kerogen-cracking gas, and the gas field had large gas thickness, high gas column characteristics and the accumulation process was first oil and then gas. The buried hill reservoir was a massive reservoir and the Kongdian reservoir was a stratified reservoir. The gas field had multi-channel hydrocarbon intense charge from overpressure source rocks, atmospheric-weak overpressure reservoir favorable for accumulation, thick overpressure mudstone caprock favorable for preservation, and natural gas ultra-late rapid accumulation model. 展开更多
关键词 OFFSHORE Bohai Bay Basin Bozhong 19-6 GAS field CONDENSATE GAS low buried HILL METAMORPHIC rock reservoir accumulation characteristics ARCHEAN
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球蚜科分类概述 被引量:8
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作者 任珊珊 乔格侠 张广学 《动物分类学报》 CSCD 北大核心 2005年第2期266-274,共9页
球蚜科是蚜虫类的一个重要类群,包括多种林业害虫和检疫害虫,本文从形态特征、生活史、寄主植物、地理分布,进化起源等方面对世界及中国球蚜物种进行了综合论述。结果表明,球蚜科具有较多原始的特征,是蚜虫中较为古老的一类;球蚜具有包... 球蚜科是蚜虫类的一个重要类群,包括多种林业害虫和检疫害虫,本文从形态特征、生活史、寄主植物、地理分布,进化起源等方面对世界及中国球蚜物种进行了综合论述。结果表明,球蚜科具有较多原始的特征,是蚜虫中较为古老的一类;球蚜具有包括异寄主全周期、异寄主不全周期、同寄主不全周期等复杂的生活周期,形成虫瘿是其主要的为害特征;球蚜科物种专性寄生在松科植物上,主要包括云杉属Picea、松属Pinus、落叶松属Larix、冷杉属Abies等属的植物,在蚜虫物种和寄主植物之间存在着平行演化的现象;球蚜的分布与寄主植物的分布相一致,主要是北半球温带和亚热带高山。世界球蚜有8属5 9种,区系成分主要是新北区、古北区。中国球蚜科有6属2 0种,分布在黑龙江、云南、四川等地,主要是古北区成分。初步推测球蚜科可能首先在松属植物上起源。 展开更多
关键词 Pinus
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Fault characteristics and control on hydrocarbon accumulation of middle-shallow layers in the slope zone of Mahu sag, Junggar Basin, NW China 被引量:2
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作者 CHEN Yongbo CHENG Xiaogan +3 位作者 ZHANG Han LI Chunyang MA Yongping WANG Guodong 《Petroleum Exploration and Development》 2018年第6期1050-1060,共11页
The development, evolution and formation mechanism of faults and their control on the migration and accumulation of Mesozoic oil and gas in the middle-shallow layers of the slope zone of Mahu sag were studied by the i... The development, evolution and formation mechanism of faults and their control on the migration and accumulation of Mesozoic oil and gas in the middle-shallow layers of the slope zone of Mahu sag were studied by the interpretation of seismic and drilling data. Two types of faults, normal and strike-slip, are developed in the middle-shallow layers of the slope zone of the Mahu sag and they are mostly active in the Yanshanian period. They are divided into four grade faults: The grade I strike-slip faults with NWW to near EW direction are related to the left-lateral transpressive fault zones in the northwest of Junggar Basin since the end of the Triassic. The grade II faults with NE to NNE direction are the normal faults located at the junction of the fault zone and the slope zone, and their formation is related to the extension at the top of the nose-like structures in the fault zone. The grade III faults, which are also the normal faults, are the result of the extension at the top of the lower uplifts in the slope zone and differential compaction. The grade IV faults with NE direction are normal faults, which may be related to the extension environment at the tip of the lower uplifts. Faults not only are the channel for the vertical migration of oil and gas, but also control the oil-gas accumulation. There are two types of oil-gas reservoirs in the middle-shallow layers of slope zone of Mahu sag: fault block reservoirs and fault-lithologic reservoirs. They have large traps and promising exploration potential. 展开更多
关键词 JUNGGAR Basin SLOPE ZONE of Mahu SAG middle-shallow layers fault genetic mechanism nose-like structure lower uplift hydrocarbon accumulation
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东海西湖凹陷中南部晚中新世构造反转与油气运聚 被引量:62
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作者 张敏强 钟志洪 +1 位作者 夏斌 孙珍 《中国海上油气(工程)》 2005年第2期73-79,共7页
解剖了西湖凹陷中南部晚中新世反转构造的结构特征,认为本区反转构造的发育部位受伸展期的基底断裂带控制。在巨厚的沉积盖层条件下,断陷构造层与拗陷构造层之间的构造特征差异明显。反转构造形态自下而上表现为叠加在断块基础上的顶厚... 解剖了西湖凹陷中南部晚中新世反转构造的结构特征,认为本区反转构造的发育部位受伸展期的基底断裂带控制。在巨厚的沉积盖层条件下,断陷构造层与拗陷构造层之间的构造特征差异明显。反转构造形态自下而上表现为叠加在断块基础上的顶厚褶皱、平行褶皱和顶薄褶皱。在伊豆小笠原弧及九州帛琉海岭与日本南缘碰撞产生的近东西向区域挤压力作用下,构造反转作用具有“下逆上褶”特征,即断陷构造层沿基底断层发生逆向反转,而拗陷构造层在力偶作用下发生不对称褶皱作用。构造反转对油气运移的控制通过构造增压和断层泄压作用进行,油气主要在断陷构造层与拗陷构造层的转换构造层聚集。 展开更多
关键词 西 西
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应用近等基因系研究Bt基因对水稻性状表现的影响 被引量:13
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作者 沈圣泉 舒庆尧 +2 位作者 包劲松 吴殿星 夏英武 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2005年第3期283-287,共5页
以密阳46(MY46)为轮回亲本,采取连续回交,结合GUS标记基因辅助选择技术,育成了Bt基因近等基因系抗螟虫密阳46(RIMY46).经考察,RIMY46及其所配杂种II32A/RIMY46的GUS反应和PCR检测均为阳性,且高抗螟虫.在早期营养生长阶段,RIMY46苗高比M... 以密阳46(MY46)为轮回亲本,采取连续回交,结合GUS标记基因辅助选择技术,育成了Bt基因近等基因系抗螟虫密阳46(RIMY46).经考察,RIMY46及其所配杂种II32A/RIMY46的GUS反应和PCR检测均为阳性,且高抗螟虫.在早期营养生长阶段,RIMY46苗高比MY46低,分蘖数比MY46少,表明纯合态Bt基因对纯系植株的前期生长进程有一定延缓作用,这种影响随着植株长大而减小,最终除导致抽穗延迟和整精米率降低外,对其余8个农艺性状和9个稻米品质性状的影响则均不显著.比较Bt近等基因系所配杂种II32A/RIMY46和II32A/MY46有关性状的表现差异,结果则发现杂合态Bt基因对杂种F1性状表达均无明显的负作用. 展开更多
关键词 BT PCR F1 GUS
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早熟高产优质多抗糖果兼用蔗新品种川蔗23号的选育 被引量:2
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作者 谭显平 李茂枝 +7 位作者 陈华平 文颖 王贵华 黄久凯 吕达 陈道德 李红梅 周英明 《甘蔗糖业》 2005年第2期6-10,5,共6页
在61点(次)省级区域和生产试验中,川蔗23号的平均出苗率为66.67%;宿根发株数为181545株/hm2;平均分蘖率为115.32%;平均株高为257cm;平均茎径为2.94cm;平均有效茎为85035株/hm2;平均单株重为1.7752kg/株;平均单产为150855kg/hm2,比川蔗1... 在61点(次)省级区域和生产试验中,川蔗23号的平均出苗率为66.67%;宿根发株数为181545株/hm2;平均分蘖率为115.32%;平均株高为257cm;平均茎径为2.94cm;平均有效茎为85035株/hm2;平均单株重为1.7752kg/株;平均单产为150855kg/hm2,比川蔗13号高28725kg/hm2,增产23.52%;平均田间锤度19.81%,比对照种高2.21%(绝对值);平均甘蔗蔗糖分为14.07%,比川蔗13号高1.72%(绝对值);甘蔗含糖量平均达21369.15kg/hm2,比川蔗13号高41.30%。在22点(次)全国甘蔗品种区域试验中,川糖89-103的平均出苗率是166.88%;分蘖率为114.14%,株高为269cm;茎径为2.81cm;有效茎是69798株/hm2,单株重是1.6290kg/株,新植宿根平均单产是11549,5kg/hm2,比全国统一对照种ROC10增产18.53%;平均甘蔗蔗糖分为14.49%,比ROC10高0.39%(绝对值);甘蔗含糖量为16209kg/hm2,比ROC10高18.40%。川蔗23号高抗黑穗病和花叶病,不感眼点病、黄斑病和褐条病等,对螟虫、蚜虫外的害虫有很强的抗性。川蔗23号商品性状优良,纤维含量低,出汁率高,蔗汁蔗糖分高,蔗茎表面光滑美观给人良好感觉。表明川蔗23号是一个农艺性状、产量性状和工艺性状及商品性状都很优秀的糖果兼用蔗品种。 展开更多
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Biochemical characters and antibiotic susceptibility of Staphylococcus aureus isolates 被引量:5
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作者 Subhankari Prasad Chakraborty Santanu Kar Mahapatra Somenath Roy 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第3期212-216,共5页
Objective:To observe the biochemical characters and antibiotic susceptibility of isolated Staphylococcia aureus(S.auerus) strains against some conventional and traditional antibiotics. Methods:Thirty post operative pa... Objective:To observe the biochemical characters and antibiotic susceptibility of isolated Staphylococcia aureus(S.auerus) strains against some conventional and traditional antibiotics. Methods:Thirty post operative pathogenic isolated S.aureus strains were used in this study. Bacterial culture was done in Mueller-Hinton broth at 37 ℃.Characters of these strains were determined by traditional biochemical tests such as hydrolysis test of gelatin,urea,galactose, starch and protein,and fermentation of lactose and sucrose.Antibiotic susceptibility were carried out by minimum inhibilory concentration test,minium bactericidal concentration test,disc agar diffusion test and brain heart infusion oxacillin screening agar.Results:Prom this study,it was observed that 100%S.aureus isolates showed positive results in gelatin,urea and galactose hydrolysis test.50%isolates were positive in starch hydrolysis test,35%in protein hydrolysis test. 100%isolates in lactose fermenting test,but no isolate was positive in sucrose fermenting test. Antibiotic susceptibility testing suggested that 20%of isolates were resistant to kanamycin and 46.67%were resistant to oxacillin.Conclusions:These findings show that all these isolates have gelatin,urea,galactose hydrolysis and lactose fermenting activity.20%of these isolates were resistant to kanamvcin and 46.67%were resistant to oxacillin. 展开更多
关键词 STAPHYLOCOCCUS AUREUS OXACILLIN Antibiotic susceptibility Minimum INHIBITORY concentration Disc AGAR diffusion Pathogen Biochemical character Bacterial culture
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准噶尔盆地中部下侏罗统三工河组二段沉积相及储层特征 被引量:37
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作者 张冬玲 鲍志东 +1 位作者 王建伟 杨文秀 《古地理学报》 CAS CSCD 2005年第2期185-196,共12页
准噶尔盆地中部下侏罗统三工河组二段广泛发育三角洲相。其下部在研究区东北部以大型辫状河三角洲前缘沉积夹滑动浊流沉积为特征,西部以扇三角洲沉积为特征,在中部两者交汇叠加。二段上部在东北部和西部都为曲流河三角洲前缘亚相,在研... 准噶尔盆地中部下侏罗统三工河组二段广泛发育三角洲相。其下部在研究区东北部以大型辫状河三角洲前缘沉积夹滑动浊流沉积为特征,西部以扇三角洲沉积为特征,在中部两者交汇叠加。二段上部在东北部和西部都为曲流河三角洲前缘亚相,在研究区中部交汇叠加。三工河组二段砂岩发育大量原生孔隙和次生孔隙,为有利储层。沉积微相类型控制了砂体的储集性能,成岩作用对砂岩储集性的改造并不强烈。二段下部的辫状河三角洲前缘河道微相及扇三角洲前缘河道微相具有大孔中渗的特点,为Ⅰ、Ⅱ类储层;上部的曲流河三角洲前缘分支河道及前缘席状砂微相,具中孔、中、低渗的特点,为Ⅱ和Ⅲ类储层。 展开更多
关键词 西
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Characterization of Congolese Strains of <i>Xanthomonas axonopodis</i>pv. <i>manihotis</i>Associated with Cassava Bacterial Blight
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作者 G. Mamba-Mbayi P. Tshilenge-Djim +1 位作者 K. K. Nkongolo A. Kalonji-Mbuyi 《American Journal of Plant Sciences》 2014年第9期1191-1201,共11页
Cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis has been reported in several African countries since 1970. Knowledge of the virulence and diversity of Xanthomonas axonopodis pv. manihotis... Cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis has been reported in several African countries since 1970. Knowledge of the virulence and diversity of Xanthomonas axonopodis pv. manihotis strains is important for an integrated control of CBB. The main objective of the present study was to characterize strains of Xanthomonas axonopodis collected from various regions in the DR-Congo. There was variability among strains for shape (form), contour (margin) and elevation. Bacterial cell size for the strains analyzed varied from 24.1 μm × 11.3 μm to 11.4 μm × 4.2 μm. All the Xanthomonas axonopodis pv. manihotis strains but one was motile. Two distinctive groups were identified based on radial growth of their colonies. The first group grows faster (7.8-10.5 mm/d) compared to the second group (4.8-6.9 mm/d). Five strains (Gandajika, Inera/Stat, Kansasa, Mulumba and Musakatshi) were classified as virulent with a damage rating ≤ 1 and four were aggressive (Luputa, M'vuazi, Boketa and Kiyaka) with a damage rating > 1. Significant differences were also observed among strains for disease onset, incidence and plant mortality. The highest incidence (33%) of bacterial blight 21 days after infestation (DAI) resulted from the Boketa strain inoculation and the lowest (0 % disease incidence) from INERA/STAT and Musakatshi strains. There was no clear association between geographic origin of the strains and their aggressiveness. 展开更多
关键词 CASSAVA Bacterial Blight (CBB) Xanthomonas axonopodis pv. manihotis Morphological and Physiological characters CBB Incidence STRAINS Aggressiveness DR-Congo
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松辽盆地断陷期超层序界面的地质属性刻画及其油气地质意义 被引量:24
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作者 蒙启安 王璞珺 +1 位作者 杨宝俊 程日辉 《地质论评》 CAS CSCD 北大核心 2005年第1期46-54,共9页
松辽盆地断陷期分为 1个超层序组、3个超层序、6个层序。从火石岭组到营城组构成一个完整的活动大陆边缘火山—断陷超层序组。三个超层序分别为同碰撞期火山—断陷超层序 (火石岭组 )、火山间歇期断陷超层序(沙河子组 )和后碰撞期火山... 松辽盆地断陷期分为 1个超层序组、3个超层序、6个层序。从火石岭组到营城组构成一个完整的活动大陆边缘火山—断陷超层序组。三个超层序分别为同碰撞期火山—断陷超层序 (火石岭组 )、火山间歇期断陷超层序(沙河子组 )和后碰撞期火山—断陷超层序 (营城组 )。超层序组底界 T5界面是前三叠纪拼合基底与侏罗系火山岩—沉积岩互层序列之间的反射界面 ,界面上下层系之间的间断时限≥ 4 5 Ma;界面之下是古亚洲洋构造域时期形成的拼合基底 ,界面之上是鄂霍次克洋构造域形成的火山—沉积建造。超层序组顶界 T4 界面是断陷期火山岩—碎屑岩互层序列与上覆坳陷期正常沉积岩层序之间的反射界面 ,界面上下层系之间的间断时限为 3~ 5 Ma;界面之下是鄂霍次克洋构造域晚期形成的火山—沉积建造 ,界面之上是太平洋构造域早期形成的坳陷期沉积层序。层序对油气的控制作用十分明显。高产工业气藏主要见于超层序组的顶界面 ;工业气藏和低产气藏主要出现在层序界面附近 ; 展开更多
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甜椒对不同程度水分胁迫-复水的生理生化响应 被引量:14
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作者 崔秀敏 王秀峰 许衡 《中国农学通报》 CSCD 2005年第5期225-229,共5页
对甜椒穴盘苗进行了不同程度的水分胁迫-复水处理,探讨了叶片某些生理生化特性的变化。结果如下:叶片RWC、渗透势随基质水分减少而降低,渗调能力逐步增强。POD、SOD、CAT酶活性随水分减少而上升,SOD对水分胁迫最敏感,复水后主要由POD、... 对甜椒穴盘苗进行了不同程度的水分胁迫-复水处理,探讨了叶片某些生理生化特性的变化。结果如下:叶片RWC、渗透势随基质水分减少而降低,渗调能力逐步增强。POD、SOD、CAT酶活性随水分减少而上升,SOD对水分胁迫最敏感,复水后主要由POD、CAT负责清除H2O2和过氧化物;游离氨基酸、脯氨酸随基质水分减少急剧上升,复水后大幅下降,可能为轻度胁迫下主要的渗调物质。RWC降至45%(停水后3d)时,可溶性蛋白和可溶性糖显著积累,明显晚于氨基酸,但它们基础含量高,主要在较为严重的水分胁迫时发挥作用。虽然水分胁迫使保护酶活性和渗透调节能力均提高,但任何程度的胁迫均不可避免地伤害幼苗。穴盘苗生产中,建议“水分胁迫锻炼”时间以不超过3d(RWC≥45%)为宜。 展开更多
关键词 CAT H2O2 RWC POD SOD
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莺歌海盆地莺东斜坡带隐蔽油气藏类型及成藏主控因素 被引量:14
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作者 何家雄 夏斌 +1 位作者 张树林 刘宝明 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2005年第2期101-107,共7页
莺东斜坡带具有“两脊一洼”分段式展布之特殊区域地质构造格局,且自北而南“两脊一洼”三段式分布具有明显不同的构造及断裂活动特征与油气运聚规律,故不同区域区带隐蔽油气藏类型及成藏主控因素差异明显,其中,北段(即北延伸脊)成藏主... 莺东斜坡带具有“两脊一洼”分段式展布之特殊区域地质构造格局,且自北而南“两脊一洼”三段式分布具有明显不同的构造及断裂活动特征与油气运聚规律,故不同区域区带隐蔽油气藏类型及成藏主控因素差异明显,其中,北段(即北延伸脊)成藏主控因素主要取决于烃源及油气运聚输导系统;中段(一洼即岭头断阶区)成藏主控因素则受控于烃源与岩性圈闭的有效性;南段(南延伸脊)成藏主控因素主要取决于地层岩性复合圈闭的有效性。根据不同类型隐蔽油气藏的成藏主控因素及分布规律,即可采取不同的研究方法及勘探技术对策,以期获得油气勘探的突破。 展开更多
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Hierarchy structure characteristics analysis for the China Loess watersheds based on gully node calibration 被引量:4
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作者 Hai-ying ZHAO Yi-peng +1 位作者 XU Yue-xue LIU Hai-ying 《Journal of Mountain Science》 SCIE CSCD 2018年第12期2637-2650,共14页
A land surface region can be decomposed into a series of watershed units with a hierarchical organizational structure. For loess landform, the watershed is a basic spatial–structural unit that can express natural lan... A land surface region can be decomposed into a series of watershed units with a hierarchical organizational structure. For loess landform, the watershed is a basic spatial–structural unit that can express natural landforms, surface morphology characteristics, spatial organization and developmental evolution. In this research we adopted the concept of node calibration in the watershed structure unit, selected six complete watersheds on China Loess Plateau as the research areas to study the quantitative characteristics of the hierarchical structure in terms of watershed geomorphology based on digital elevation model(DEM) data, and then built a watershed hierarchical structure model that relies on gully structure feature points. We calculated the quantitative indices, such as elevation, flow accumulation and hypsometric integral and found there are remarkably closer linear correlation between flow accumulation and elevation with increasing gully order, and the same variation tendency of hypsometric integral also presented. The results showed that the characteristics of spatial structure become more stable, and the intensity of spatial aggregation gradually enhances with increasing gully order. In summary, from the view of gully node calibration, the China Loess watershed structure shows more significantly complex, and the developmental situation variation of the loess landforms also exhibited a fairly stable status with gully order increasing. So, the loess watershed structure and its changes constructed the complex system of the loess landform, and it has the great significance for studying the spatial pattern and evolution law of the watershed geomorphology. 展开更多
关键词 Digital ELEVATION models Flow accumulation GULLY structure feature point Hypsometric integral LOESS LANDFORM NODE CALIBRATION
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郯庐断裂对垦东地区构造和成藏的影响 被引量:22
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作者 付兆辉 李敏 《海洋石油》 CAS 2005年第2期15-19,共5页
垦东地区位于郯庐断裂带的渤海段,其形成、演化以及呈现出来的地质特征均受郯庐大断裂控制,进而影响油气成藏。受断裂带影响和控制,垦东地区的断裂整体为NE或NNE走向的雁列式分布的多条断裂。古近纪的伸展运动形成了垦东地区的断陷盆地... 垦东地区位于郯庐断裂带的渤海段,其形成、演化以及呈现出来的地质特征均受郯庐大断裂控制,进而影响油气成藏。受断裂带影响和控制,垦东地区的断裂整体为NE或NNE走向的雁列式分布的多条断裂。古近纪的伸展运动形成了垦东地区的断陷盆地,沉积了古近系的厚地层,发育了该区最主要的一套烃源岩。受郯庐大断裂的影响,垦东地区可根据构造特征分成三个带:西部主体带、东部斜坡带和北部斜坡带,不同构造带的构造特征差别较大。受区域地质运动的影响,垦东地区部分地层缺失,钻遇的地层主体为:明化镇组、馆陶组、东营组、沙河街组、中生界、古生界。地质特征中,低凸起格局、新近系活跃的构造运动和长期继承性发育的大型披覆构造三个方面影响了油气的富集和成藏。 展开更多
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何首乌块根中砷、镉、汞和铅含量的检测及其富集特性 被引量:9
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作者 李正 杭悦宇 周义峰 《植物资源与环境学报》 CAS CSCD 2005年第2期54-55,共2页
The contents of As, Cd, Hg and Pb in root tubers of annual and biennial plants of Polygonum multiflorum Thunb. in Jiangsu Province were 0.32, 0.24, 0, 1.25 and 0.20, 0.26, 1.67×10 -4, 1.32 mg·kg -1 respectiv... The contents of As, Cd, Hg and Pb in root tubers of annual and biennial plants of Polygonum multiflorum Thunb. in Jiangsu Province were 0.32, 0.24, 0, 1.25 and 0.20, 0.26, 1.67×10 -4, 1.32 mg·kg -1 respectively, which totally met the standards of GTSIEMPP (WM2—2001). Biology concentration factors (BCF) of Cd is 2.4-2.6, which indicates that the root tuber of P. multiflorum has a strong accumulative action to Cd. While the accumulative action to As, Hg and Pb is not strong, BCF are 0.025-0.015, 0-6.40×10 -4 and 0.06 respectively. 展开更多
关键词 strong action root and the The met BCF are As Cd Hg Pb in is to
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渤海湾盆地孔西潜山构造带碳酸盐岩的成藏史数值模拟 被引量:10
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作者 孟元林 王粤川 +5 位作者 罗宪婴 高建军 肖丽华 周新桂 殷秀兰 王志国 《地质力学学报》 CSCD 2005年第1期11-18,共8页
通过碳酸盐岩成藏要素生、储、盖、运、圈、保的数值模拟,建立了成藏史数值模拟系统,并以渤海湾盆地黄骅坳陷孔西潜山构造带为例说明了这一系统的应用。研究表明,孔西潜山构造带奥陶系烃源岩在印支期开始排烃,一次成藏开始;燕山期进入... 通过碳酸盐岩成藏要素生、储、盖、运、圈、保的数值模拟,建立了成藏史数值模拟系统,并以渤海湾盆地黄骅坳陷孔西潜山构造带为例说明了这一系统的应用。研究表明,孔西潜山构造带奥陶系烃源岩在印支期开始排烃,一次成藏开始;燕山期进入大量生、排烃阶段,成为本区的主要生烃期和成藏期;之后,一次生烃中止;喜马拉雅期该构造带进一步被埋深,开始二次生烃和第三次成藏,二次生烃的量较小。所以黄骅坳陷下古生界原生油气藏的勘探应注重那些位于生烃区在印支期和燕山期形成且未被后期构造运动破坏的古构造。 展开更多
关键词 西
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A Philosophic Idea of Being "ALIVE" in Living Educational Theory——Talking about the Character Education in the New Curriculum
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作者 田凤俊 Moira Laidlaw 《固原师专学报》 2005年第2期94-97,共4页
This paper is mainly discussing about the significance of the Living Educational Theory Action Research raised by Dr. Jack Whitehead, also it gives a clear distinction between traditional AR Theory and that in the LET... This paper is mainly discussing about the significance of the Living Educational Theory Action Research raised by Dr. Jack Whitehead, also it gives a clear distinction between traditional AR Theory and that in the LETAR. Because of the distinctive features like "individual", "living" and "practical" characteristics been embodied in the Living Educational Theory, it can be very well applied in the character education of improvement in the individual and group practice, therefore, implementation of the "New Curriculum" as a case to prove what has been discussed. 展开更多
关键词 the TALKING NEW Idea practical Research applied Action CLEAR group and like case can it AR be
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等量紫云英条件下化肥用量对早稻养分吸收和干物质积累的影响 被引量:23
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作者 徐昌旭 谢志坚 +3 位作者 许政良 苏全平 李水荣 秦文婧 《江西农业学报》 CAS 2010年第10期13-14,23,共3页
在施用等量紫云英条件下进行了不同化肥用量对早稻养分吸收和干物质积累影响的田间试验。试验结果表明:在翻压紫云英22500kg/hm2的条件下,早稻田可减少化肥用量20%~60%,但是以减少化肥用量20%的效果最佳,能有效促进水稻植株地上部对N、... 在施用等量紫云英条件下进行了不同化肥用量对早稻养分吸收和干物质积累影响的田间试验。试验结果表明:在翻压紫云英22500kg/hm2的条件下,早稻田可减少化肥用量20%~60%,但是以减少化肥用量20%的效果最佳,能有效促进水稻植株地上部对N、P、K养分的吸收与积累,同时有利于地上部干物质的积累。 展开更多
关键词 ASTRAGALUS SINICUS Early Rice Dry Matter Accumulation Nutrient Absorption
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A 4-Corner Codes Classifier Based on Decision Tree Inductive Learning for Handwritten Chinese Characters
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作者 钱国良 王亚东 舒文豪 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第2期26-31,共6页
The classification for handwritten Chinese character recognition can be viewed as a transformation in discrete vector space. In this paper, from the point of discrete vector space transformation, a new 4-corner codes ... The classification for handwritten Chinese character recognition can be viewed as a transformation in discrete vector space. In this paper, from the point of discrete vector space transformation, a new 4-corner codes classifier based on decision tree inductive learning algorithm ID3 for handwritten Chinese characters is presented. With a feature extraction controller, the classifier can reduce the number of extracted features and accelerate classification speed. Experimental results show that the 4-corner codes classifier performs well on both recognition accuracy and speed. 展开更多
关键词 Handwritten Chinese character recognition classification discrete vector space transformation DECISION tree INDUCTIVE learning 4-corner CODES
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