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Four new highly brominated and fully substituted mono- and bis-phenols, 1-(2,3,6-tribromo-4,5-dihydroxybenzyl)pyrrolidin-2-one (1), 1,2-bis(2,3,6-tribromo-4,5-dihydroxyphenyl)ethane (2), 6-(2,3,6-tribromo-4,5-dihydroxybenzyl)-2,5-dibromo-3,4-dihydroxybenzyl methyl ether (3), and 2,3,6-tribromo-4,5-dihydroxybenzyl methyl sulfone (4), were characterized from the marine red alga Symphyocladia latiuscula. In addition, five known bromophenols, bis(2,3,6-tribromo-4,5-dihydroxyphenyl)methane (5), bis(2,3,6-tribromo-4,5-dihydroxybenzyl) ether (6), 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (7), 2,3,6-tribromo-4,5-dihydroxymethylbenzene (8), and 2,3,6-tribromo-4,5-dihydroxybenzaldehyde (9), were also isolated and identified. The structures of these compounds were elucidated by spectroscopic methods including 1D and 2D NMR as well as by low- and high-resolution mass spectrometric analysis. Structurally, all of these compounds are highly brominated and fully substituted, and contain one or two 2,3,6-tribromo-4,5-dihydroxyphenyl unit(s) in each of the molecules. In addition, compound 4 possesses a unique sulfone structural feature. Each of the isolated compounds was evaluated for alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radical-scavenging activity and all were found to be potent, with IC50 values ranging from 8.1 to 24.7 mu M, compared to the known positive control butylated hydroxytoluene (BHT), with an IC50 of 81.8 mu M.

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干涉合成孔径雷达 (Interferometric Synthetic Aperture Radar,InSAR) 是以合成孔径雷达复数据提取的相位为信息源获取地表三维信息和海表散射体运动信息的新型微波成像雷达。 InSAR通过两幅天线同时观测 (单轨模式),或两次近平行的观测 (重复轨道模式),获取地面或海面同一景观的复图像对。20世纪90年代以来,InSAR陆地和海洋研究成为微波遥感的热点,广泛应用于地表变形监测、南极冰流测量、地面或海面慢速运动目标检测等领域。 近年来,国际上逐渐应用机载顺轨或交轨干涉合成孔径雷达进行海表面流速测量以及海面波成像机制研究。相对于传统单天线合成孔径雷达 (Synthetic Aperture Radar, SAR),双天线干涉合成孔径雷达 (InSAR) 测量海表面波有着独特的优势: (1) InSAR复图像的相位近似正比于海面散射体的径向速度,这种内在的成像机制提供了直接测量海表面动态运动的机会。 (2) 真实孔径雷达调制传递函数几乎对InSAR相位图像没有影响,而对传统SAR图像影响较大。 基于干涉合成孔径雷达测量海浪的优势,本文做了一些干涉合成孔径雷达海浪遥感理论与应用研究工作,主要内容大致可归纳如下: (1)基于新建立的顺轨干涉合成孔径雷达 (Along-Track Interferometric Synthetic Aperture Radar,ATI-SAR) 相位谱与海浪谱之间的非线性映射关系,通过数值模拟研究了不同雷达参数和海况参数对应的ATI-SAR相位谱。数值模拟结果表明:距离速度比率、雷达入射角、天线间距和有效波高和波长比率是影响ATI-SAR海浪成像的重要因素。进一步,利用机载X波段水平极化相位图像和机载C波段水平极化相位图像谱结合方向波骑士浮标测量的海浪方向谱验证了ATI-SAR相位谱与海浪谱之间的非线性映射关系。结果显示用前向映射关系计算的相位谱与实际观测的相位谱较为一致,二者相关系数总体大于0.6,而且对成像非线性不敏感. (2)建立了包含海表面高度和速度聚束的交轨干涉合成孔径雷达 (Across-Track Interferometric Synthetic Aperture Radar,XTI-SAR) 涌浪干涉相位模型,得到了涌浪成像的解析表达式,进一步研究了XTI-SAR沿方位向传播的涌浪成像机制。定义二次谐波振幅与基波振幅比率来表征成像非线性,通过比较XTI-SAR和ATI-SAR相位的二阶调和分量,分析不同海况和干涉SAR参数情况下的数值模拟,结果表明:当速度聚束弱时,XTI-SAR相位比ATI-SAR相位具有较强的非线性,ATI-SAR比XTI-SAR更适合测量海浪。当速度聚束强时,XTI-SAR相位比ATI-SAR相位具有较弱的非线性,XTI-SAR比ATI-SAR更适合测量海浪。 (3)基于包含海表面高度和速度聚束的交轨干涉合成孔径雷达 (XTI-SAR) 涌浪干涉相位模型,结合多维高斯变量的特征函数方法建立了新的XTI-SAR相位谱与海浪谱非线性积分变换。新积分变换不同于Bao (1999) 建立的积分变换,两者形式上区别在于新积分变换中包含了长波径向轨道速度一阶倒数项。数值模拟显示:通常情况下,长波径向轨道速度一阶倒数项不能忽略。进一步,我们针对不同雷达参数和海况结合新非线积分变换对XTI-SAR海浪成像进行了数值模拟,结果表明:同顺轨干涉合成孔径雷达 (ATI-SAR) 海浪成像一致,距离速度比率 和有效波高与波长比率 是影响XTI-SAR海浪成像的重要因子。 (4)基于新的ATI-SAR相位谱与海浪谱之间的非线性映射关系,发展了利用ATI-SAR相位图像反演海浪方向谱的参数化反演模式,并由此得到海浪波长、波向和有效波高。反演结果与现场浮标观测结果比较一致。相对于其它反演模式,参数化反演模式的优点在于:(1) 不需要任何附加信息如初猜海浪谱、散射计提供的风速风向等信息。 (2) 不需要对相位图像进行辐射定标,可以由反演的海浪谱直接计算有效波高。(3) 反演结束后还可以得到成像区域的局地风速信息。因此,参数化反演模式可以实现风、浪信息的联合反演。

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附着生物又称污损生物,是附生在海洋设施和生物体表面的动物、植物和微生物等生物的总称(Azis et al., 2001)。附生在养殖器材和生物体表面的数量巨大的附着生物,对贝类养殖和海湾生态系统内的物质和营养盐循环等多个方面产生影响。本研究以北方重要的养殖海湾----桑沟湾为研究对象,对贝藻养殖区附着生物的群落演替及其生态效应进行了研究。主要研究结果如下: ① 2007年5月至2008年5月,采用挂网的方法对桑沟湾栉孔扇贝和海带混养区的附着生物的季节变化进行了研究。结果显示挂网上的附着生物具有显著的季节变化特征,网片上的附着生物湿重与水温的变化相一致,生物量为3~1210 g•m-2。2月份附着生物的生物量最低,8月份最高。2007年9月至11月,对栉孔扇贝养殖笼上和贝壳上的附着生物种类和数量进行了研究。结果显示9月份养殖笼上附着生物的湿重约为1.94 kg,10月份降至0.99 kg,11月份又稍有增加,为1.03 kg。扇贝壳上的附着生物变化趋势与养殖笼上的相同,9~11月份壳上附着生物的数量约0.49~2.09 g。扇贝养殖笼上可鉴定的大型附着生物约23种,包括藻类、海鞘类、苔藓虫类、环节动物、腔肠动物、软体动物、甲壳动物和海绵动物等。玻璃海鞘、柄海鞘、紫贻贝和苔藓虫等是附着生物群落中的优势种。 ② 通过在栉孔扇贝和虾夷扇贝上壳上添加不同重量的“模拟附着生物”(速凝水泥)的方法,研究了贝壳上附着生物的重量对这两种扇贝生长和存活的影响。结果显示水泥重量是上壳重0.5-3倍的各组实验组扇贝的生长和存活与对照组(未添加水泥的扇贝)之间没有显著差异。说明贝壳上附着生物重量为上壳的3倍重时,也不会显著影响扇贝生长存活。9-11月份贝壳上的自然附着生物的重量约为1.47-2.09 g,为上壳重的28.16 (±38.6)%—31.29 ± (31.63)%。因此,贝壳上附着的生物重量不太可能对扇贝的生长存活造成显著的负面影响。 ③ 在桑沟湾现场测定了玻璃海鞘和柄海鞘的生物沉积速率。9月份(水温约24℃)玻璃海鞘和柄海鞘的生物沉积速率分别为32.14和90.06 mg•ind-1•d-1或(858.99 和467.76 mg•gdw-1•d-1),据此计算,养殖笼上的两种海鞘的生物沉积速率约为84.29 mg•m-2•d-1。海区的自然沉积速率为41.49 mg•m-2•d-1;玻璃海鞘和柄海鞘沉积物中有机质含量分别为14.34%和13.77%,对照组海区自然的有机质含量为14.36%;以上三者有机碳的含量分别为24.72%,23.74%和24.76%;氮的含量分别为0.27%和0.25%,自然沉积物中的氮含量为0.30%。9月份扇贝养殖笼上附着的海鞘将产生2588.16吨的沉积物,即向底部沉积363.77吨的有机物、6.99吨的氮和1.79吨的磷。 ④ 通过测定扇贝养殖笼上优势种附着生物--玻璃海鞘、柄海鞘和贻贝的摄食、呼吸和排泄,研究了这些优势种类对贝类养殖和海湾环境的影响。9月份(水温约24.5℃)玻璃海鞘和柄海鞘对颗粒有机物(POM)的摄食率分别为14.30 和17.01 mg• h-1•ind-1。根据实验结果计算这两种海鞘摄取的颗粒有机物相当于312个扇贝的摄取量,大于笼内养殖的扇贝的摄取量;玻璃海鞘和柄海鞘的耗氧率分别约为0.32和0.18 mg•h-1•ind-1,养殖笼上的这两种海鞘消耗的溶解氧约等于75个扇贝消耗的溶解氧。栉孔扇贝、玻璃海鞘、柄海鞘和贻贝的排氨率分别为33.66 ±11.34,117.90±23.46,35.91±6.22,28.08±3.41 ug NH4-N•gdw-1•h-1。以此估算,9月份玻璃海鞘、柄海鞘和贻贝每天排泄的氨氮约为654.08 kg,相当于16467吨栉孔扇贝(鲜重)排泄的氨氮。海鞘和贻贝排泄的氨氮可提供浮游植物等所需的2.75%的氮,可以提供1204吨海带的生长所需的氮。 ⑤ 一个养殖笼内的栉孔扇贝和全部附着生物(Scallop Culture Unit, SCU)在夏季(6-9月)对颗粒有机物的摄食速率约为43.13-98.94 mg/h,平均74.05 mg/h,期间桑沟湾养殖的栉孔扇贝及附着生物摄取的POM约为1279.58吨;同期,SCU对氨氮和磷(PO4-P)的排泄速率分别为125.59-1432.23 μmol•h-1和76.2-252.89μmol•h-1,期间桑沟湾养殖扇贝及附着生物排泄的氮磷分别为211.09 吨和83.79 吨。一串牡蛎及吊绳和牡蛎壳上的附着生物(Oyster Culture Unit, OCU),夏季摄食率为5-41.43μmol•h-1,耗氧率为16.54-41.76μmol•h-1,对氨氮和磷(PO4-P)的排泄速率分别为35.56-489.34μmol•h-1 和9.92-16.68μmol•h-1。以此估算,夏季OCU可摄取POM535.68吨,消耗溶解氧955.58吨,排泄氮磷分别为62.37 吨和15.50 吨。

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植物有机体稳定碳同位素组成受植物生长期间气候环境因子的影响,包含了大量的环境信息。要真正理解植物体同位素组成所包含的环境信息首先要研究植物体同位素组成与环境之间的关系。文章通过分析2002年和2003年青藏高原东部青海省门源县境内隶属于19科41属51种植物叶片的δ~(13)C值,研究高寒草甸植物稳定碳同位素组成的年间变化及其与环境因子的关系,分析影响δ~(13)C值变化的关键因子。结果表明,所测植物的δ~(13)C值分布在一个很小的范围-29.2‰~-24.9‰之间,平均值为-26.9‰,说明所测植物的光合作用均通过C3途径实现,这可能与该研究区较低温度有关。研究发现一年生植物δ~(13)C值明显低于多年生植物,而且一年生和多年生植物δ~(13)C值之间的差异在2002年(t=-3.031,P〈0.01)和2003年(t=-3.567,P〈0.001)均能达到显著性水平,表明多年生植物水分利用效率显著高于一年生植物,能更好的适应该地区寒冷干燥的低温环境。两年间植物δ~(13)C值有明显不同,2003年显著低于2002年(t=6.786,P〈0.001)。通过分析两年间环境因子的变化认为植物叶片δ~(13)C值的年间变化主要是由于降水的变化引起的,随降雨量的增加而降低。不同植物种δ~(13)C值年间变化差别很大,反应了植物对环境变化的不同响应。在植被恢复中应选用植物δ~(13)C值随环境变化存在较大差异的物种,因为此类物种能够采取不同的对策适应该地区环境的变化。

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选择青藏高原东北隅海北站区的4种高寒草甸土壤进行高分辨率采样,测定土壤有机碳及其^14C信号;应用^14C示踪技术探讨高寒草甸土壤有机碳更新周期和CO2通量.研究得出海北站高寒草甸生态系统土壤有机碳储量在22.12×10^4~30.75×10^4kgC•hm^-2之间,平均为26.86×10^4kgC•hm^2.高寒草甸土壤有机碳的更新周期从表层的45~73a随深度增加到数百年甚至数千年或更长.高寒草甸生态系统土壤呼吸的CO2通量变化于103.24—254.93gC•m^-2•a^-1之间,平均为191.23gC•m^-2•a^-1.土壤有机质分解产生的CO2通量变化于73.3~181gC•m^-2•a^-1之间.矮嵩草草甸土壤30%以上的有机碳贮存在土壤表层(0~10cm)的活动碳库中,土壤有机质更新产生的CO2占整个剖面有机质更新产生的CO2通量的72.8%~81.23%.响应于全球变暖,青藏高原高寒草甸生态系统土壤有机碳的储量、流量、归宿变化等问题有待进一步研究.

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The x- and y-type high molecular weight (HMW) glutenin subunits are conserved seed storage proteins in wheat and related species. Here we describe investigations on the HMW glutenin subunits from several Pseudoroegneria accessions. The electrophoretic mobilities of the HMW glutenin subunits from Pd. stipifolia, Pd tauri and Pd strigosa were much faster than those of orthologous wheat subunits, indicating that their protein size may be smaller than that of wheat subunits. The coding sequence of the Glu-1St1 subunit (encoded by the Pseudoroegneria stipifolia accession PI325181) was isolated, and found to represent the native open reading frame (ORF) by in vitro expression. The deduced amino acid sequence of Glu-1St1 matched with that determined from the native subunit by mass spectrometric analysis. The domain organization in Glu-1St1 showed high similarity with that of typical HMW glutenin subunits. However, Glu-1St1 exhibited several distinct characteristics. First, the length of its repetitive domain was substantially smaller than that of conventional subunits, which explains its much faster electrophoretic mobility in SDS-PAGE. Second, although the N-terminal domain of Glu-1St1 resembled that of y-type subunit, its C-terminal domain was more similar to that of x-type subunit. Third, the N- and C-terminat domains of Glu-1St1 shared conserved features with those of barley D-hordein, but the repeat motifs and the organization of its repetitive domain were more similar to those of HMW glutenin subunits than to D-hordein. We conclude that Glu-1St1 is a novel variant of HMW glutenin subunits. The analysis of Glu-1St1 may provide new insight into the evolution of HMW glutenin subunits in Triticeae species. (C) 2007 Elsevier Ltd. All rights reserved.

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A series of significant oil-gas exploration progresses have been achieved in Nanpu depression with 1.02 billion ton oil-gas reserves have been proven. It has been confirmed that Nanpu beach has a geologic condition to be a major field based on exhaustive research. This finding, which is integrated reservoir,great reserves, thick oil layer and high productivity in Nanpu depression, is the most excited success in Chinese oil-gas exploration in recent years. This abundant oilfield found is significant to the strategy of oil production stability in the east of China. Nanpu depression exploration is also a crucial exploration project for Petrochina. Based on the comprehensive research on Nanpu formation testing data, we reevaluate and analyze the reservoir property and the structure characteristics, and propose a series of testing technique that are suitable for Jidong oil field development. The results are summarized as follows: 1. The reservoir parameters and characters are defined by formation test data interpretation and systemic dynamic-static data comparison. 2. Based on sources analysis and statistical research related to formation contaminants, some technique measures, which can not only prevent or reduce invasion damage for different formations but also can effectively improve completion efficiency, are proposed. 3. By selecting the testing pressure drawdown, optimum working regulation and flow /shut-in duration, and adopting dynamic-static flow parameters correlation analysis to predict production, an optimum research on working regulation and flow /shut-in duration was accomplished. Optimization formation test principles suitable for any kinds of Nanpu oilfield are established, which can improve test quality, construction efficiency and data recording quality. 4. By reasonable selection of perforating gun and penetrating charge, the perforation penetration has been improved effectively and the flow channel of the oil gas have been expanded, so that the communication between formations and the wellbore is improved better. 5. One joint working procedure which combining formation test, perforation, unloading and stimulation treatment has become the dominant testing technology in the Nanpu offshore Oilfield. This combination technique can implement several procedures using one pipe string, and achieve rapid testing purpose.

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孟恩陶勒盖银铅锌铟多金属矿床位于内蒙古东部,是产于海西期酸性岩浆岩体内部的热液脉状矿床,40多个矿体分布于东西长6km、南北宽200~1000m的范围内,成矿温度西高东低。矿床有用组分以Pb、Zn为主,伴生有Ag、Sn、In和Ga,其中Ag 1800t,Sn2000多t,In 400多t,Ga 100多t,构成一个典型的多金属矿床。一部分Ag以银矿物形式存在,另一部分Ag存在于方铅矿和闪锌矿中。除锡石和黄锡矿外,方铅矿也含有较高的锡。In和Ga主要存在于闪锌矿中。矿石中w(Ag)=82×10^-6~516×10^-6,w(Cd)=94×10^-6~1430×10^-6,w(In)=12×10^-6~295×10^-6,w(Ga)=3×10^-6~82×10^-6;方铅矿中w(Ag)=1580×10^-6~4995×10^-6,w(Sn)=735×10^-6~2785×10^-6,In和Ga很低;闪锌矿中w(Ag)=280×10^-6~2030×10^-6,w(Cd)=0.18%~0.44%,w(In)=85×10^-6~2660×10^-6,w(Ga)=11×10^-6~155×10^-6。从西向东,Sn和In含量降低,Ag和Ga含量增高。这一变化与成矿温度由西向东的降低一致。

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