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本文从赤潮发生前的现场模拟实验、赤潮发生时的现场培养实验和赤潮发生过程中的现场调查等方面,较为系统地研究了东海大规模赤潮对微型浮游动物群落结构的影响。 2005年长江口及邻近海区赤潮发生前,赤潮973MC2005-03航次在本海区进行了综合调查,期间分别于4月27日、5月4日和5月8日,在zzf1、zc18a和ra5三个站位利用现场船基培养的方法,研究了添加到赤潮密度106 cells L-1的东海原甲藻(Prorocentrum donghaiense)对微型浮游动物群落结构的影响。结果发现,赤潮密度的东海原甲藻对小型无壳纤毛虫的种群数量影响较大,而对中大型砂壳纤毛虫的影响较小,从而使得微型浮游动物群落有向中大型砂壳纤毛虫演替的趋势。在zzf1站位,小型无壳纤毛虫占绝对优势,添加东海原甲藻72 h后,优势种由管游虫(Cyrtostrombidium sp.)演替为另一种小型无壳纤毛虫急游虫4(Strombidium sp.4);在以中型砂壳纤毛虫百乐拟铃虫(Tintinnospsis beroidea)为优势种的zc18a站位,仍然是以此为优势种,但其在群落中的优势度更加明显;ra5站位也是以小型无壳纤毛虫为主,添加东海原甲藻72 h后,其群落结构由急游虫2(Strombidium sp.2)向中大型砂壳纤毛虫纤毛虫百乐拟铃虫和亚速岛网纹虫(Favella azorica)演替。不同站位微型浮游动物群落结构变化的差异与其本身的群落结构组成有一定关系,也与浮游植物的群落组成有关。zzf1和ra5站位实验组中微型浮游动物的总丰度和总生物量都低于对照组,而zc18a站位变化不明显,这是由于前两个站位实验组中的优势种管游虫(zzf1站位)和急游虫2(ra5站位)的丰度和生物量迅速下降,而zc18a站位实验组的优势种百乐拟铃虫的丰度和生物量比较稳定造成的。 2005年长江口及邻近海区赤潮发生时,赤潮973 MC2005-04航次在本海区进行了综合调查,期间分别于5月26日、5月28日、5月28日和5月29日,在xzm1、srb、sra1和hb8a四个站位利用现场培养的方法,研究了东海大规模赤潮对微型浮游动物群落结构的影响。结果发现,东海大规模赤潮对微型浮游动物群落结构的影响与赤潮藻的密度密切相关:xzm1、srb和sra1站位是赤潮区,两种赤潮藻的总密度分别为,1.3×106 cells L-1、1.8×106 cells L-1和5.6×106 cells L-1,而hb8a站位位于非赤潮区,两种赤潮藻的总密度仅为5×105 cells L-1;实验进行72 h后,在以大型砂壳纤毛虫网纹虫和筒壳虫(Tintinnidium sp.)为主的xzm1、srb和sra1站位,仍然是以这些大型砂壳纤毛虫为主,且其在群落中的百分比显著增大,尤其在赤潮藻密度最高的的sra1站位,这种演替趋势表现的最明显;而在以小型无壳纤毛虫急游虫2为主的hb8a站位,微型浮游动物群落向中型砂壳纤毛虫真丁丁虫(Eutintinnus sp.)演替。培养过程中微型浮游动物总丰度的变化以及总生物量的变化都与赤潮藻的密度密切相关:赤潮藻密度较低的xzm1站位和srb站位变化不大;赤潮藻密度较高的sra1站位则快速下降;而非赤潮区的hb8a站位呈快速上升的趋势。以上结果进一步表明东海大规模赤潮能使微型浮游动物群落向中大型砂壳纤毛虫演替。 在2006年4月18日-5月30日,赤潮973项目MC2006航次在长江口及其邻近海区围绕东海原甲藻和米氏凯伦藻赤潮进行了综合调查。为了研究该过程中微型浮游动物群落结构的变化,我们在南北5个断面共计21个站位进行了取样,样品涉及赤潮发生前期、发生期和消退期。本次调查共发现纤毛虫66种,其中砂壳纤毛虫有8属37种,寡毛类无壳纤毛虫25种,另外还有前口类3属4种。在赤潮发生前之前,小型无壳纤毛虫的丰度普遍较高,平均值为1574 ind L-1,而中大型砂壳纤毛虫的丰度普遍偏低,平均值仅为14 ind L-1;赤潮发生以后,在大多数站位小型无壳纤毛虫的丰度出现不同程度的下降,平均值降为171 ind L-1,而中大型砂壳纤毛虫的丰度出现一定程度的上升,平均值增至216 ind L-1。赤潮消退时,小型无壳纤毛虫丰度的平均值降为109 ind L-1,而中大型砂壳纤毛虫的丰度继续增长,变为401 ind L-1。不同微型浮游动物百分比的统计结果也表明:微型浮游动物群落由小型无壳纤毛虫向中大型砂壳纤毛虫演替的趋势:小型无壳纤毛虫在群落中百分比的平均值由赤潮发生前的62 %变为赤潮发生时的32 %,至赤潮消退时又降为15 %;而中大型砂壳纤毛虫百分比的平均值从赤潮发生前的10 %变为赤潮发生时的24 %,至赤潮消退时增至50 %。典型站位za3、za5、zb7和zb9的结果再次表明了赤潮发生过程中微型浮游动物群落由小型无壳纤毛虫向中大型砂壳纤毛虫演替的趋势。 由以上赤潮发生前的现场模拟实验、赤潮发生时的现场培养实验和赤潮发生过程中的现场调查的结果均可见,东海大规模赤潮可以改变微型浮游动物的群落结构,呈现由小型无壳纤毛虫向中大型砂壳纤毛虫演替的趋势,进而有可能影响中大型浮游动物等摄食者的种群数量和群落结构,最终可能会影响整个海洋生态系统的结构和功能。

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The nitric oxide synthase (NOS) activity in the haemocytes of shrimps Fenneropenaeus chinensis (Osbeck) and Marsupenaeus japonicus (Bate) was Studied after white spot syndrome virus (WSSV) infection to determine its characteristics in response to virus infection. First, the NOS activity in haemocytes of shrimps was determined by the means of NBT reduction and changes in cell conformation. And the variations of NOS activity in shrimps after challenge with WSSV intramuscularly were evaluated through the analysis Of L-citrulline and total nitrite/nitrate (both as NO derivates) concentrations. The result showed that NOS activity in the haemocytes of F chinensis increased slightly from 0 to 12 h postchallenge, indicated by the variations Of L-Citrulline (from 11.15 +/- 0.10 to 12.08 +/- 0.64 mu M) and total nitrite/nitrate concentrations (from 10.45 +/- 0.65 to 12.67 +/- 0.52 mu M). Then it decreased sharply till the end of the experiment (84 h postchallenge), the concentrations Of L-Citrulline and total nitrite/nitrate at 84 It were 1.58 +/- 0.24 and 2.69 +/- 0.70 mu M, respectively. The LPS-stimulated NOS activity kept constant during the experiment. However, in M. japonicus, the NOS activity kept increasing during the first 72 It postchallenge, the concentrations Of L-Citrulline and total nitrite/nitrate increased from 7.82 +/- 0.77 at 0 h to 10.79 +/- 0.50 mu M at 72 h, and from 8.98 +/- 0.43 at 0 h to 11.20 +/- 0.37 mu M at 72 h, respectively. Then it decreased till the end of the experiment (216 h postchallenge), and the concentrations of L-Citrulline and total nitrite/nitrate at 216 h were 5.66 +/- 0.27 and 4.68 +/- 0.16 mu M, respectively. More importantly, an apparent increase of I-PS-stimulated NOS activity was observed in M japonicus at 48 h postchallenge, which was about 4 times higher than that in the control group of health shrimps. In correspondence with the difference of NOS activity between the two species of shrimps, the Cumulative mortalities of the shrimps were also different. All shrimps of F. chinensis in the mortality experiment died in 66 h, much more quickly than M. japonicus, Whose accumulative mortality reached 100% after 240 h. Data here reported let us hypothesize that NOS activity in the haemocytes of shrimps F chinensis and M. japonicus responses to WSSV infection differently, and this might be one of the reasons for the different susceptibility of F chinensis and M. japonicus to WSSV infection. (c) 2005 Elsevier Inc. All rights reserved.

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本研究运用RT—PCR技术,首次从大熊描Ailuropoda melanoleucu的肌肉组织总RNA中成功克隆了核糖体蛋白S15(RPS15)基因的表达序列.并对其进行了初步分析。结果表明:大熊猫RPS15基因的表达序列全长为442bp,开放阅读框(ORF)为438bp,编码145个氨基酸,该蛋白的分子量为17.0401KDa,等电点为10.3,含有2个依赖于cAMP和cGMP的蛋白激酶磷酸化位点,5个蛋白激酶C磷酸化位点,4个N-酰基化位点及1个RPS19蛋白signature位点。进一步分析发现,大熊猫RPS15基因的表达序列及其编码的氨基酸序列与已报道的部分哺乳动物具有很高的相似性。

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含氮类荧光试剂2-(11H-苯[a]咔唑)乙基氯甲酸酯 (BCEC-Cl) 经柱前衍生处理后,采用荧光检测及柱后在线质谱鉴定对食品中胺类化合物进行了测定.标记反应在pH 9的硼酸缓冲液中进行,3 min后获得稳定的荧光产物.衍生物于λex=279 nm激发条件下产生强烈荧光,其发射波长在λem=380 nm处.产物的分离在Eclipse XDB-C8色谱柱 (150 mm×4.6 mm,5 μm)上进行,采用梯度洗脱对12种脂肪胺衍生物进行了优化分离.采用大气压化学电离源(APCI Source)正离子模式进行在线的柱后质谱鉴定,实现了多种脂肪胺衍生物的快速、准确测定.建立的方法具有良好的重现性,回归系数大于0.9996,检出限为1.8~14 fmol.

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对江河源区人工草地群落特征、多样性及其稳定性的研究结果表明,不同处理草地植物群落的物种丰富度、多样性、均匀度指数因时间和空间的变化而有明显的差异,群落演替从5龄到6龄,各群落丰富度和多样性指数增加,生物生产量降低,群落相似性系数增大.5龄老芒麦+早熟禾混播人工草地(LP5)群落的地上生物量最高(379.6 g/m2),老芒麦单播(ES5)居中(323.4 g/m2),对照组(CKF5和CK5)最低(124.3和118.6 g/m2).6龄植物群落地上生物量依次为原生植被+封育(VP6,310.1 g/m2)>老芒麦+早熟禾混播(LP6,216.3 g/m2)>老芒麦单播(ES6,190.8 g/m2)>对照(CK6,88.7 g/m2).群落间相似性系数的变化说明,单播(ES)与混播(LP)人工草地群落有趋同演化的趋势.人工草地群落随着结构的复杂化,与对照群落间的相似性提高,说明群落处于退化演替阶段,物种丰富度和多样性增大,群落稳定性提高.

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针对文献中有关瞬时生长率概念和计算方法的错误 ,将瞬时生长率重新定义为给定生长指标对生长时间的一阶导数。并建议 ,首先采用曲线回归方法建立生长模型—生长指标关于生长时间的函数 ,然后通过求一阶导数得到瞬时生长率随生长时间变化的表达式 ,利用该表达式计算任意时刻的瞬时生长率。采用黑线仓鼠的例子说明该计算过程。

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The present study was conducted to determine the effects of supplementary feeds, oat hay (OH), highland barley straw (HBS) and multi-nutrient blocks supplementation (UMMB) on reducing liveweight losses of both yak cows and calves grazed on low quality pastures during cold season. The trials of OH and HBS supplementation were conducted by using completely random design on 104 yak cows between 6 and 12 years of age as the following treatments: pure grazing (41 animals, body weight 230 67 kg) as control (CK); grazing+1.5 kg DM of OH per head daily (30 animals, body weight 216 28 kg); gazing. 1.5 kg DM of HBS per head daily (33 animals, body weight 221 34 kg). The trial of UMMB was conducted on three types of yaks, 1-year calves (8-12 months old, body weight 61.1 6.9 kg), 2-year calves (18-24 months old, 98.0 11.3 kg) and yak cows (164.5 27.1 (S.D.) kg) with 20 animals in control group (CK) and 20 animals in supplement group for each type by using completely random design as the following treatments: pure grazing for CK group; grazing+ 150, 250 and 500 g UMMB per day averagely for 1-year calf, 2-year calf and cow at night. The results indicate that the animals supplemented with oat hay received body weight gain (32 20.7 g day(-1)), while those supplemented with highland barley straw still suffered from body weight loss (-56.7 39.3 a day(-1)); UMMB supplementation can decrease the body weight loss by 109.7%, 86.6% and 63.4% for the 1-year calves, 2-year calves and yak cows, respectively, as compared with pure grazing. Around US$1.60 output can be achieved on the basis of US$1 input for UMMB supplementation in the farming systems of the 1-year calves, 2-year calves and yak cows, while US$1 input can produce US$1.55 and 1.14 output for OH and FIBS supplementations, respectively, in yak cows' farming system. It can be preliminary concluded that UMMB supplementation was the most economic way to alleviate body weight loss of grazing yaks over cold season, and the higher productive returns were obtained from OH supplementation for grazing yak cows during winter/spring months. © 2004 Elsevier B.V All rights reserved.

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本论文以青藏高原东北部海北地区高寒灌丛(Alpine Shrub)生态系统为研究对象,利用微气象观测系统及涡度相关(Eddy Covariance)技术,自2003年1月1日至2005年12月31日对该类广布于青藏高原的典型高寒草地类型进行长期连续观测。在对生态系统CO2净交换(NEE)以及群落叶面积指数(LAI)、生物量等生物学指标和光合有效辐射(PAR)、温度、土壤水分、脉冲性降水事件等主要环境因子进行连续监测的基础上,重点分析和探讨了海北地区高寒灌丛生态系统净生态系统CO2交换(NEE)在时、日、月及年际尺度上的变化模式,生长季与非生长季高寒灌丛生态系统CO2净交换特征,高寒灌丛生态系统大气CO2源/汇年际差异,土壤温度、昼夜温差、光合有效辐射、脉冲性降水事件等主要环境因子影响。从而,揭示了不同时间尺度下的高寒灌丛生态系统NEE变化规律,阐明主要环境因子对生态系统NEE的影响,明确了该生态系统大气CO2源/汇状况及其季节分布模式;同时,也为青藏高原区域尺度的高寒草地生态系统CO2通量研究和碳收支的估算提供科学依据和基础数据,对进一步揭示我国乃至亚洲陆地生态系统的碳收支状况有着重要意义。主要研究结果概括为以下几个方面: 1、海北地区高寒灌丛生态系统净生态系统CO2交换时动态特征存在很大的季节性差异,暖季小时NEE变化振幅大,CO2净吸收的极值一般出现在午间,最大吸收量为1.7 g CO2 m-2 h-1左右。夜间为CO2净释放,净生态系统交换值较为稳定(0.5~ 0.9 g CO2 m-2 h-1);冷季日变化振幅极小,除14:00~18:00时一定量CO2释放外,其余时段通量均很小。 2、从日平均净生态系统CO2交换来看,6~9月日平均NEE一般为负值(CO2净吸收),2003~2005年6~9 月间日平均NEE分别为-5.65 g CO2 m-2 d-1、-6.08 g CO2 m-2 d-1和-4.81 g CO2 m-2 d-1;而10~12月及翌年1~5月期间日平均NEE通常为正值(CO2净释放),该时段3年高寒灌丛日平均净生态系统CO2交换分别为1.91 g CO2 m-2 d-1、1.90 g CO2 m-2 d-1和2.19 g CO2 m-2 d-1。2003~2004年高寒灌丛生态系统CO2净释放维持天数分别为249 d、 254 d和264 d,2003年净释放维持天数最少,而净吸收维持天数2005年最少(101d)。2003、2004和2005年全年日平均CO2净吸收分别为0.611 g CO2 m-2 d-1、0.759 g CO2 m-2 d-1和0.167 g CO2 m-2 d-1。 3、就季节差异而言,2003、2004和2005年整个生长季节高寒灌丛平均CO2日净生态系统交换分别为-3.99 g CO2 m-2 d-1、-4.59 g CO2 m-2 d-1、-3.27 g CO2 m-2 d-1。7、8月生长季节CO2净吸收的最高,2003、2004、2005年7月和8月份高寒灌丛生态系统CO2净吸收分别为222 g CO2 m-2 和224 g CO2 m-2、355 g CO2 m-2和216 g CO2 m-2、263 g CO2 m-2和186 g CO2 m-2。在相对短暂的生长季节海北地区高寒灌丛生态系统表现出显著的大气CO2净吸收能力,2003、2004和2005年生长季节高寒灌丛生态系统CO2净吸收量分别为610 g CO2 m-2、701 g CO2 m-2和500 g CO2 m-2。相对于温度等环境因子,高寒灌丛生态系统生长季白昼NEE小时变化规律更受光合有效辐射变化的影响。 4、2003~2005年非生长季节日平均NEE分别为1.83 g CO2 m-2、2.01 g CO2 m-2和2.07 g CO2 m-2。4月和10月是非生长季节CO2净释放的最高月份,2003、2004和2005年全月净释放量为105 g CO2 m-2和77 g CO2 m-2、105 g CO2 m-2和117 g CO2 m-2及105 g CO2 m-2和138 g CO2 m-2,2003~2005年整个非生长季CO2净释放分别为CO2为388 g CO2 m-2、425 g CO2 m-2和439 g CO2 m-2。非生长季节海北地区高寒灌丛生态系统NEE小时变化与5 cm土壤温度存在极显著的正相关关联,表明在非生长季节土壤温度是影响青藏高原高寒灌丛生态系统NEE的重要环境因子。 5、从生态系统CO2源/汇特征来看,海北地区高寒灌丛生态系统2003、2004和2005年全年净CO2固定总量分别为223 g CO2 m-2 a-1、277 g CO2 m-2 a-1和61 g CO2 m-2 a-1,3年平均CO2值为187 g CO2 m-2 a-1。在为期3年的研究时段海北地区高寒灌丛生态系统表现为弱的大气二氧化碳的汇。 6、高寒灌丛群落表观光合量子产额(a)和表观最大光合速率(Pmax)受叶面积指数的影响。在6~9月份期间,由于LAI的不同,a和Pmax值差异明显,7、8月份较高而6月和9月明显较低。海北地区高寒灌丛生态系统a和Pmax值高于西藏当雄地区高寒草甸生态系统,但低于平原地区相关生态系统。 维持天数2005年最少(101d)。2003、2004和2005年全年日平均CO2净吸收分别为0.611 g CO2 m-2 d-1、0.759 g CO2 m-2 d-1和0.167 g CO2 m-2 d-1。 3、就季节差异而言,2003、2004和2005年整个生长季节高寒灌丛平均CO2日净生态系统交换分别为-3.99 g CO2 m-2 d-1、-4.59 g CO2 m-2 d-1、-3.27 g CO2 m-2 d-1。7、8月生长季节CO2净吸收的最高,2003、2004、2005年7月和8月份高寒灌丛生态系统CO2净吸收分别为222 g CO2 m-2 和224 g CO2 m-2、355 g CO2 m-2和216 g CO2 m-2、263 g CO2 m-2和186 g CO2 m-2。在相对短暂的生长季节海北地区高寒灌丛生态系统表现出显著的大气CO2净吸收能力,2003、2004和2005年生长季节高寒灌丛生态系统CO2净吸收量分别为610 g CO2 m-2、701 g CO2 m-2和500 g CO2 m-2。相对于温度等环境因子,高寒灌丛生态系统生长季白昼NEE小时变化规律更受光合有效辐射变化的影响。 4、2003~2005年非生长季节日平均NEE分别为1.83 g CO2 m-2、2.01 g CO2 m-2和2.07 g CO2 m-2。4月和10月是非生长季节CO2净释放的最高月份,2003、2004和2005年全月净释放量为105 g CO2 m-2和77 g CO2 m-2、105 g CO2 m-2和117 g CO2 m-2及105 g CO2 m-2和138 g CO2 m-2,2003~2005年整个非生长季CO2净释放分别为CO2为388 g CO2 m-2、425 g CO2 m-2和439 g CO2 m-2。非生长季节海北地区高寒灌丛生态系统NEE小时变化与5 cm土壤温度存在极显著的正相关关联,表明在非生长季节土壤温度是影响青藏高原高寒灌丛生态系统NEE的重要环境因子。 5、从生态系统CO2源/汇特征来看,海北地区高寒灌丛生态系统2003、2004和2005年全年净CO2固定总量分别为223 g CO2 m-2 a-1、277 g CO2 m-2 a-1和61 g CO2 m-2 a-1,3年平均CO2值为187 g CO2 m-2 a-1。在为期3年的研究时段海北地区高寒灌丛生态系统表现为弱的大气二氧化碳的汇。 6、高寒灌丛群落表观光合量子产额(a)和表观最大光合速率(Pmax)受叶面积指数的影响。在6~9月份期间,由于LAI的不同,a和Pmax值差异明显,7、8月份较高而6月和9月明显较低。海北地区高寒灌丛生态系统a和Pmax值高于西藏当雄地区高寒草甸生态系统,但低于平原地区相关生态系统。

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本文介绍了一种适用于移动机器人的宜人化遥操作系统,该系统利用双目图像进行环境场景的三维重建,并对移动机器人及其载荷机械臂进行几何及运动学建模,结合图形学技术生成虚拟机器人、虚拟机械臂和虚拟地形.操作者在该虚拟环境中可以对虚拟机器人及虚拟机械臂进行反复规划和仿真直至规划路径准确无误.该系统可以应用于星球探测机器人和危险作业机器人的仿真验证,具有重要的实用价值。

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China locates between the circum-Pacific and the Mediterranean-Himalayan seismic belt. The seismic activities in our country are very frequent and so are the collapses and slides of slope triggered by earthquakes. Many collapses and slides of slope take place mainly in the west of China with many earthquakes and mountains, especially in Sichuan and Yunnan Provinces. When a strong earthquake happening, the damage especially in mountains area caused by geological hazards it triggered such as rock collapses, landslides and debris flows is heavier than that it caused directly. A conclusion which the number of lives lost caused by geological hazards triggered by a strong earthquake in mountains area often accounts for a half even more of the total one induced by the strong earthquake can be made by consulting the statistical loss of several representative earthquakes. As a result, geological hazards such as collapses and slides of slope triggered by strong earthquakes attract wide attention for their great costs. Based on field geological investigation, engineering geological exploration and material data analysis, chief conclusions have been drawn after systematic research on formation mechanism, key inducing factors, dynamic characteristics of geological hazards such as collapses and slides of slope triggered by strong earthquakes by means of engineering geomechanics comprehensive analysis, finite difference numerical simulation test, in-lab dynamic triaxial shear test of rock, discrete element numerical simulation. Based on research on a great number of collapses and landslides triggered by Wenchuan and Xiaonanhai Earthquake, two-set methods, i.e. the method for original topography recovering based on factors such as lithology and elevation comparing and the method for reconstructing collapsing and sliding process of slope based on characteristics of seism tectonic zone, structural fissure, diameter spatial distribution of slope debris mass, propagation direction and mechanical property of seismic wave, have been gotten. What is more, types, formation mechanism and dynamic characteristics of collapses and slides of slope induced by strong earthquakes are discussed comprehensively. Firstly, collapsed and slided accumulative mass is in a state of heavily even more broken. Secondly, dynamic process of slope collapsing and sliding consists of almost four stages, i.e. broken, thrown, crushed and river blocked. Thirdly, classified according to failure forms, there are usually four types which are made up of collapsing, land sliding, land sliding-debris flowing and vibrating liquefaction. Finally, as for key inducing factors in slope collapsing and sliding, they often include characteristics of seism tectonic belts, structure and construction of rock mass, terrain and physiognomy, weathering degree of rock mass and mechanical functions of seismic waves. Based on microscopic study on initial fracturing of slope caused by seismic effect, combined with two change trends which include ratio of vertical vs. horizontal peak ground acceleration corresponding to epicentral distance and enlarging effect of peak ground acceleration along slope, key inducing factor of initial slope fracturing in various area with different epicentral distance is obtained. In near-field area, i.e. epicentral distance being less than 30 km, tensile strength of rock mass is a key intrinsic factor inducing initial fracturing of slope undergoing seismic effect whereas shear strength of rock mass is the one when epicentral distance is more than 30 km. In the latter circumstance, research by means of finite difference numerical simulation test and in-lab dynamic triaxial shear test of rock shows that initial fracture begins always in the place of slope shoulder. The fact that fracture strain and shear strength which are proportional to buried depth of rock mass in the place of slope shoulder are less than other place and peak ground acceleration is enlarged in the place causes prior failure at slope shoulder. Key extrinsic factors inducing dynamic fracture of slope at different distances to epicenter have been obtained through discrete element numerical simulation on the total process of collapsing and sliding of slope triggered by Wenchuan Earthquake. Research shows that combined action of P and S seismic waves is the key factor inducing collapsing and sliding of slope at a distance less than 64 km to initial epicenter along earthquake-triggering structure. What is more, vertical tensile action of P seismic wave plays a leading role near epicenter, whereas vertical shear action of S seismic wave plays a leading role gradually with epicentral distance increasing in this range. On the other hand, single action of P seismic wave becomes the key factor inducing collapsing and sliding of slope at a distance between 64 km and 216 km to initial epicenter. Horizontal tensile action of P seismic wave becomes the key factor gradually from combined action between vertical and horizontal tensile action of P seismic wave with epicentral distance increasing in this distance range. In addition, initial failure triggered by strong earthquakes begins almost in the place of slope shoulder. However, initial failure beginning from toe of slope relates probably with gradient and rock occurrence. Finally, starting time of initial failure in slope increases usually with epicentral distance. It is perhaps that the starting time increasing is a result of attenuating of seismic wave from epicenter along earthquake-triggering structure. It is of great theoretical and practical significance for us to construct towns and infrastructure in fragile geological environment along seism tectonic belts and conduct risk management on earthquake-triggered geological hazards by referring to above conclusions.

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在1.0、2.0GPa和873~1223K的温压条件下,借助于1260阻抗一增益相位分析仪测定了叶蜡石的电导率,并用阻抗谱原理分析了其微观导电机制。实验结果表明:样品的电导率对频率具有很强的依赖性;电阻率随着温度的升高而减小,电导率随着温度升高而增大,logσ与1/T之间符合Arrenhius线性关系;叶蜡石在1.0GPa和2.0GPa的压力下脱水温度分别为1074K和1101K。根据本次获得的电导率实验结果并结合前人对滑石族所做的工作,得出了与前人不同的结论:滑石族矿物脱水电导率曲线出现了转折点。

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对贵阳市区到农村地区的石生藓类氮含量进行了系统分析,并根据藓类氮含量(y,%)和大气氮沉降(x,kghm^-2a^-1)的平均定量关系(y=0.052x+0.7325)计算了各采样点的大气氮沉降值。贵阳地区大气氮沉降的变化范围为0.91~44.69kghm^-2a^-1,市区大气氮沉降最高平均(29.21±6.17)kghm^-2a^-1,主要来自城市废水NH3释放;最低平均(11.95±3.95)kghm^-2a^-1,出现在城市和农村的结合地带,主要原因在于来自市区的氮污染物减少、且大量分布了环城林带、农业活动相对较低;20km以外的农村地区大气氮沉降略微升高(平均(14.31±5.11)kghm^-2a^-1),主要反映了农业施肥导致NH3释放的增加。结果表明,石生藓类氮含量是一种经济可靠的大气氮沉降监测工具,能够较准确地量化大气氮沉降的水平,并为深入研究大气氮沉降的生态环境效应提供基础资料。

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矿床的开采和选冶,常常将其中重金属有毒元素释放到环境中,铅锌矿造成的环境污染尤为严重。贵州都匀牛角塘矿床是国内外少见的富镉锌矿床,其中镉高度富集。本文通过对通过对矿区水、土壤及植物的分析和调查,发现其中镉和锌均已远远超过国家标准,矿区周围环境已受到严重污染。研究表明矿床的表生风化作用是镉等重金属释放的主要途径之一,更重要的是矿山的采矿和选矿更加剧了其释放量,虽在目前人群中没有明显中毒现象,可能是由于矿床开采时间较短,Cd等重金属元素在人体中积累不多所致。但矿山环境污染是污染元素长期积累造成的结果,即使在矿山关闭十年、上百年甚至上千年时间内,矿山尾矿淋滤液对环境生态的影响依然存在。因此,在矿山开发过程中必须注意矿床中有用元素的综合利用和重视环境保护,防患于未然。特别是对这类富含有毒污染元素的金属矿山的开采更应如此。

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应用高精度离子探针锆石U—Pb测年方法,获得普朗斑岩铜矿床中3件矿化石英二长斑岩的锆石年龄分别为228.4-3Ma、226.3±2.8Ma、226±3Ma。锆石形态和铀钍参数均属典型的岩浆锆石特征,年龄值在误差范围内近似一致,表明形成矿化斑岩的中酸性岩浆从岩浆房快速上升侵位。结合前人已发表的矿化斑岩的黑云母Ar—Ar坪年龄及辉钼矿Re-Os同位素年龄等数据,推测普朗斑岩铜矿的岩浆-热液系统从岩浆侵入至矿化阶段的持续时间可能长达lOMa以上,主成矿期约为216~214Ma。从岩浆房分异出的富含成矿物质和挥发份的岩浆流体在相对较晚阶段对普朗复式岩体发生了强烈的蚀变作用并可能进一步萃取了岩体中的成矿物质。