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Search Results: 1 - 10 of 274516 matches for " 张晟宇 "
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新场气田蓬一气藏经济采收率研究
,
天然气工业 , 2002,
Abstract: ?经济采收率是经济可采储量与探明地质储量之比,反映了地质储量中有利润价值的储量部分,它随着经济参数的变化而变化。文章在总结新场气田蓬一气藏地质模型和动态特征的基础上,利用翁氏模型预测法、对数正态模型法对气藏进行可采储量计算和产量预测,在对比两种数学模型预测结果后,选择对数正态模型预测的产量值,利用现行的经济参数,采用净现值法对气藏的经济采收率进行计算,为储量的资产化和气藏经营提供了可靠依据。
三峡水库香溪河库湾蓝藻水华暴发特性及成因探析
杨敏,,胡征
湖泊科学 , 2014, DOI: 10.18307/2014.0306
Abstract: 2008年夏季,香溪河库湾自三峡水库建库以来第1次暴发蓝藻水华,水华波及整个库湾,持续时间达1个月之余.为了解这次水华暴发特性及发生原因,本文对蓝藻水华的发生发展过程进行了跟踪调查,6-7月水华发生期间每周采样1次.调查表明本次蓝藻水华的优势种为鱼腥藻(Anabaenasp.)、铜绿微囊藻(Microcystisaeruginosa)、惠氏微囊藻(Microcystiswesenbergii)等,细胞密度高达3.82×108cells/L,蓝藻相对密度达到90%以上.本文将2008年5-7月与2007年同期理化指标比较发现,2007年5月的N:P为18.6,而2008年5月的N:P较低,为6.2,据文献报道N:P<8有利于微囊藻的复苏,因此2008年水华前期的低N:P利于微囊藻的复苏,为微囊藻在适宜条件下的大量增殖提供了种源基础.方差分析表明,2008年5-7月各采样点真光层深度显著高于2007年同期,使得底泥中的微囊藻获得一定强度的光照而复苏,这可能是2008年蓝藻水华在香溪河库湾暴发的原因之一.综上所述,在具备充足的营养盐基础、较强的水体稳定性以及较高水温的前提下,香溪河库湾水华发生前期较低的N:P以及较高强度的光照可能是微囊藻复苏的诱导因子,为蓝藻水华暴发提供了种源基础.
养殖池塘小气候调节生态服务价值的实证研究
,,杨正勇,杨怀,海清,郭宗香
长江流域资源与环境 , 2010,
Abstract: 养殖池塘在为人类提供水产品的同时通过水面水汽蒸发及周围植被的蒸腾作用发挥增湿调温小气候调节功能。对其生态服务价值做出准确的评估,可为利益相关者正确衡量水产养殖业对社会发展的贡献、继而制定正确决策提供科学依据,并为该领域的研究提供讨论的基础。为此,以上海市青浦区淀山湖水源保护区养殖池塘作为研究对象,以该区常规鱼类养殖池塘的跟踪观测数据为基础,结合相关统计数据和估计模型,定量分析了该区域池塘养殖的小气候调节生态服务价值。研究表明该区养殖池塘小气候调节生态服务价值约为1.794亿元/a(183437.67元/(hm2·a))。池塘养殖的小气候调节生态服务价值季节性变动明显.
越瓜型砧木对甜瓜的生长、产量及品质的影响
赵依杰,,小红,,陈阳
园艺学报 , 2011,
Abstract:
表达谱芯片分析KCTD15对3T3-L1前体脂肪细胞的影响
,金康宣,,徐梓辉
第三军医大学学报 , 2014,
Abstract: 目的通过筛选分析3T3-L1前体脂肪细胞中KCTD15基因敲低后的差异表达基因研究其细胞生物学功能,探讨KCTD15基因与肥胖发生的关联。方法①运用RNA干扰技术在3T3-L1前体脂肪细胞中特异性敲低KCTD15基因表达,并用半定量RT-PCR技术检测KCTD15基因敲低效率。②用Illumina表达谱芯片检测基因表达。③筛选差异表达基因后,运用GeneOntology(GO)和KEGGpathway进行功能聚类分析。④挑选部分差异表达基因进行半定量RT-PCR验证。结果①KCTD15基因敲低后筛选到833个差异表达基因(差异倍数值≥2或≤0.5)。②GO功能分析显示差异表达基因主要富集在以下相关通路:细胞黏附(34个)、细胞骨架组装(26个)、生物膜组装(26个)、染色体组装(20个)、脂肪细胞分化(6个);KEGGpathway分析则显示半乳糖代谢和二羧酸代谢受到影响。③对MTHFD1、MDH1、VSP4B、CUX1、ABCA75个基因表达的半定量RT-PCR与芯片测试结果相符。结论KCTD15基因功能与生物膜和细胞骨架有关且能够影响细胞能量代谢过程。
苦瓜籽核糖体失活蛋白的纯化与性质研究
包凌,,钱正旭,,孟延发
中国生物工程杂志 , 2008,
Abstract: 采用丙酮分级沉淀、superdex75分子筛层析和bluesepharosecl-6b亲和层析,从苦瓜籽中获得核糖体失活蛋白(rip)。纯化的rip经page、sds-page、ief和periodate-schiff分析均为单一蛋白着色带或单一糖蛋白着色带,根据sds-page计算其相对分子量为30kda,经ief-page计算其pi为9.0,采用硫酸-苯酚法测得其含糖量为1.05%。光谱学性质研究表明:最大紫外吸收峰为280nm,以278nm波长光激发时,该蛋白具有304nm荧光发射峰和316nm副峰,以295nm波长光激发时,该蛋白的最大荧光发射峰在317nm。体外生物活性试验表明其对人白血病细胞k562和人肝癌细胞具有明显抑制作用,而对完整细胞毒性极小。
河流植物群落下底泥中碳氮磷和重金属富集效应分析
王晓,,,,,王莹莹,小伟,刘茂松
南京林业大学学报(自然科学版) , 2017, DOI: 10.3969/j.issn.1000-2006.2017.02.004
Abstract: 【目的】探明河流植物群落下的底泥中碳氮磷和重金属的积累机制。【方法】在淮河上游地区索河流域不同生境类型(浅滩区和浅水区)下分别选取3处当地优势植物扁秆?草(Scirpus planiculmis)和黑三棱(Sparganium stoloniferum)单优势群落,采集植物群落下和对照(植物盖度<5%)0~10 cm(表层)、≥10~20 cm(中层)和≥20~30 cm(下层)处的底泥,用独立样本t检验分析植物群落下3个层次的底泥中OC(有机碳)、TN(全氮)、TP(全磷)、As、Cd、Co、Cr、Cu、Hg、Ni、Pb和Zn是否有显著富集效应,计算底泥中各元素的相对富集指数E(relative enrichment index, E),并用偏最小二乘回归(PLSR)法分析相对富集指数的影响因素。【结果】扁秆?草和黑三棱群落下的底泥中OC、TN、As、Cd、Cr、Hg、Ni、Pb和Zn有显著富集作用,且富集作用主要发生在表层底泥。整体上,植物群落下0~30 cm深的底泥中OC、TN和各重金属的E值主要受到各元素在底泥中本底值的影响,其次为植物种类,再次为生境类型,而底泥质地对其影响相对较小。【结论】在污染河流中种植当地优势挺水植物种可以使河流中的营养元素和重金属定向转移到植物群落下的底泥中,尤其是表层底泥中。这其中的主要驱动力表现为植物对水体中颗粒物和营养物质的拦截,以及植物枯落物和死亡根系的分解及矿化。扁秆?草可能对Cd、Cr、Hg、Pb和Zn有吸收富集作用。
【Objective】Investigate the mechanism of organic carbon(OC), total nitrogen(TN), total phosphorus(TP)and heavy metal(As, Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn)accumulation in sediment of plant communities in river. 【Method】We selected three sites dominated by Scirpus planiculmis and Sparganium stoloniferum each in shoal and shallow water habitats of the Suo River, a tributary of the Huai River. We collected sediment from the surface layer(0-10 cm), middle layer(≥10-20 cm)and sublayer(≥20-30 cm)of the plant communities and CK(blank control). We analyzed the accumulation of OC, TN, TP and heavy metals in the sediment of three layers using t-tests for independent samples; calculated relative enrichment index (E)of OC, TN, TP and heavy metals in the sediment of three layers; and then used partial least squares regression to analyze the influence of various factors on each element’s E.【Result】OC, TN, As, Cd, Cr, Hg, Ni, Pb and Zn were significantly enriched in sediment of the S. planiculmis and S. stoloniferum communities. The enrichment effect mainly occurred in the surface sediment. Overall, the main factors influencing the elements’ E values were the elements’ background values in the sediment, followed by plant species, habitat type, and sediment texture. 【Conclusion】The results of the present study provide a reference for the ecological restoration of polluted rivers. Planting local dominant species in polluted rivers helps transfer carbon, nutrient elements and some heavy metals from the river ecosystem into the sediment of the plant communities, especially into the surface sediment. The main driving forces may be plants’ interception of particulate matter and nutrients in the water, as well as the decomposition and mineralization of plant litter and dead roots. It is also possible that S. planiculmis can absorb Cd, Cr, Hg, Pb and Zn and that S. stoloniferum can absorb As, Cd, Cr, Hg, Ni, Pb and Zn, although this
内蒙古阿拉善北部杭乌拉地区圆包山组时代、沉积特征及大地构造意义
尹海权,周洪瑞,程瑞,维杰,郑小明,杨立业,李杰,
沉积学报 , 2015, DOI: 10.14027/j.cnki.cjxb.2015.04.005
Abstract: 通过阿拉善北部杭乌拉地区圆包山组碎屑锆石峰值年龄(420±3Ma和419.6±3.6Ma)以及圆包山组底部层位发育的笔石、头足类化石,认为圆包山组形成时代并非早志留世,而是泥盆纪.圆包山组中发育的大量沉积构造及其岩性特征,表明了圆包山组为典型的半深海—深海浊积岩沉积,但鲍马序列发育不完整,主要有AE、ABE、ADE和ABDE等序列组合,并划分了内扇、中扇和外扇三个沉积亚相.研究区位于阿拉善地区北部,属于西伯利亚板块南缘部分,是研究古亚洲洋闭合时间的关键部位.早古生代硅质岩岩石特征表明,研究区在早古生代处于一个被动大陆边缘的稳定大地构造背景.自晚古生代开始,研究区的大地构造活动性开始增强,逐渐由被动大陆边缘转变为活动大陆边缘,并形成了巨厚的浊积岩.根据浊积岩中槽模、沟模等沉积构造确定了物源区为研究区北部的西伯利亚板块,并根据浊积岩岩性、沉积特征以及砂岩地球化学特征的研究,认为研究区晚古生代早期的浊积岩形成于西伯利亚板块南缘的活动大陆边缘,并同时受岛弧作用的影响,导致浊积岩具有岛弧物源区属性.结合圆包山组中碎屑锆石特征及其年龄可以进一步确定圆包山组物源区位于研究区北部Gobi-Altai构造带.
正常人群步行足偏角与年龄特征分析
Analysis of the relevance of age and toe out angle of normal adults' gait

顾琳燕,邱华平,,陈益丹,许瑛,金肖青,宁钢民
- , 2018, DOI: 10.7507/1001-5515.201606082
Abstract: 老年人群由于运动能力退化及受到疾病的影响,容易导致步态异常,而异常步态通常会增加老年人的跌倒风险,带来严重伤害。本文重点对正常无运动功能障碍人群的步态运动学参数进行了研究分析,目的是为了研究不同年龄阶段步态参数的特征,探索步态参数在运动机能评估和临床诊断中的作用。本研究基于电子步道采集步态数据,对足偏角和足间夹角等一系列特征以及这些特征与受试者年龄、性别等因素的相关性进行了定量分析。研究结果表明,大部分受试者正常步行时呈正向步态,足偏角会随着年龄的增长而变大,在中青年期变化缓慢,但进入老年后(>60 岁)左足偏角和足间夹角明显升高,变化产生的差异具有统计学意义,研究结果还提示足间夹角是一种普适性强的步态参数。通过本文的研究结果提示,对足偏角进行定量分析有望成为一种对人体下肢运动能力评估及膝关节疾病诊断的便捷、有效的方法。
Due to the decline of motor ability and the impact of the diseases, abnormalities in gait is common in the elderly population, which will raise the risk of fall and cause serious injury. This study focuses on the analysis of the gait kinematics parameters of normal adults’ gait, aiming to investigate the characteristics of gait parameters in different age groups and to explore the role of gait parameters in motor function assessment and clinical diagnosis. Based on the gait data gained by electronic walkway, the relationship among the toe out angles and their correlation with age and gender etc. were quantitatively analyzed. The results show that most normal subjects walk with positive toe out angles, and the angles increase with age. Such changes are slow in the young and middle age groups. However, the elevations of the left out toe angle and the angles between the feet are statistically significant after entering elder age ( >60 years). The results also suggest that the angle between the feet is a kind of practical gait parameter for varying applications. This study concludes that feet angle analysis is potential to provide a convenient and quantitative tool for the assessment of lower limb motor ability and the diagnosis of knee joint diseases.
内蒙古阿拉善北部杭乌拉地区早古生代硅质岩地球化学特征及其构造意义
Geochemical characteristics and its tectonic significance of the Early Paleozoic siliceous rocks in Hangwula area of northern Alxa,Inner Mongolia

郑小明,尹海权,高磊,,王艳凯,周洪瑞,维杰
- , 2017, DOI: 10.7605/gdlxb.2017.03.038
Abstract: 内蒙古阿拉善北部杭乌拉地区位于中亚造山带的中段南缘,处于西伯利亚板块、塔里木板块和华北板块之间,是研究中亚造山带和古亚洲洋演化的重要区域。文中以杭乌拉地区硅质岩地球化学特征为主要研究内容,结合前人研究结果,对阿拉善北部地区早古生代构造背景进行分析。杭乌拉地区下古生界西双鹰山组和班定陶勒盖组硅质岩镜下可见黏土、陆源粉砂和放射虫等,表现为明显的沉积成因特征。硅质岩地球化学特征一致性较差,其中FeMnAl等主量元素、Sc/Th值、(La/Ce)n值和δCe值反映出硅质岩为大陆边缘沉积,(La/Yb)n值反映硅质岩接近于远洋沉积背景,δEu 值表现为无热液作用影响,VV/YTi/V值多接近于洋中脊和大洋盆地硅质岩特征,U/ThBa/Sr值也属于热水成因硅质岩特征。硅质岩稀土元素配分曲线呈平坦状,无明显的右倾(大陆边缘轻稀土元素富集配分模式)和左倾(开放洋盆重稀土元素富集配分模式)特征。研究区早古生代地质记录相对较少,但是鉴于该地区晚古生代复杂的构造演化特征及其对早古生代古地理格局的继承,并结合上述硅质岩地球化学特征,认为研究区在早古生代为一个多岛洋环境。
Hangwula area of the northern Alxa in Inner Mongolia,located on the southern margin of the middle Central Asian Orogenic Belt(CAOB)and dominated by the Siberian Plate in its north,the Tarim Plate in its west and the North China Plate in its south,is one of the most typical areas for researching tectonic evolution of the CAOB and the Paleo-Asian Ocean. In this article,geochemical characteristics of the Early Paleozoic siliceous rocks were mainly studied to re-establish the tectonic evolution of the northern Alxa in Early Paleozoic combining with the previous results. The Early Paleozoic siliceous rocks of the Xishuangyingshan Formation and the Bandingtaolegai Formation in the Hangwula area were identified to contain clay,terrigenous silt and radiolarians under the microscopic analysis,which reveals that these siliceous rocks were of the distinct sedimentary origin. However,these Early Paleozoic siliceous rocks showed poor uniformity on their geochemical characteristics: The discrimination diagrams of major elements like Fe,Mn,Al and the ratio analyses of rare earth elements(REEs)like Sc/Th,(La/Ce)n,and δCe indicate that the siliceous rocks belong to the stable continental margin deposits;but(La/Yb)n value reflects a pelagic sedimentary background. δEu value shows that the origin process of the siliceous rocks was without hydrothermal participation. The ratio analyses of trace elements like V/Y,Ti/V conform to the ocean ridge or the ocean basin setting,but the U/Th and Ba/Sr radios accord with the hydrothermal feature. REE distribution patterns of the Early Paleozoic siliceous rocks are relatively flat with positive europium
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