909 resultados para think aloud
Resumo:
We have investigated the optical properties of asymmetric multiple layer stacked self-assembled InAs quantum dot with different interlayer. We found that asymmetric multiple stacked QD samples with In0.2Ga0.8As + GaAs interlayer can afford a 180nm flat spectral width with strong PL intensity compared to other samples at room temperature. We think this result is due to the introduction of In0.2Ga0.8As strain-reducing layer. Additionally, for the broad spectral width and the strong PL intensity, this structure can be a promising candidate for quantum-dot superluminescent diodes.
Resumo:
米亚罗地区是四川西部较为典型的亚高山针叶林区域之一。为建立该地区主要针叶树种岷江冷杉、云杉、紫果云杉和红杉的年轮宽度年表资料,了解不同海拔高度岷江冷杉原始林和不同恢复过程的人工针叶林及次生混交林树木径向生长规律,结合样地调查,用生长锥钻取了树木芯样做年轮生态学分析。芯样经过标准化程序固定和打磨抛光后,用WinDENDRO图像分析系统测量年轮宽度序列,用COFECHA程序交叉定年和控制测量数据质量,用ARSTAN程序建立了4个主要针叶树种的地区年表和不同海拔高度岷江冷杉林及人工针叶林和次生混交林针叶树的样地年表。 4个主要针叶树种年轮宽度年表的平均敏感度低于0.2,而其晚材宽度年表都具相对较高的平均敏感度。早材宽度与年轮总宽度标准化年表间的相关系数均在0.9以上;晚材宽度与年轮总宽度标准化年表间的相关系数则种间差异较大,红杉的最高,岷江冷杉的最低。岷江冷杉晚材宽度与年轮总宽度的相关性从1970年以后明显下降,而其他种的相关系数则随时间变化较小。树种之间标准化年表显著正相关,而云杉与紫果云杉和红杉与岷江冷杉之间相关系数明显较高。年表序列的第1主分量表达了4个树种树木共同径向生长变化格局;第2至第4主分量分别表达了云杉属和冷杉属、常绿针叶树种和落叶针叶树种以及云杉和紫果云杉树木径向生长变化差异。 不同海拔高度的8个岷江冷杉样地年轮宽度年表序列敏感度大体上随海拔高度升高而降低。各样地早材宽度与年轮总宽度年表之间的相关系数均在0.9以上,且随海拔高度变化不大;晚材宽度与年轮总宽度之间的相关系数随海拔高度的变化较大,并有随海拔升高而降低的趋势。样地年表序列之间相关系数差异很大,高海拔样地年表间多为显著正相关;低海拔样地年表间的相关系数变化不一;高海拔和低海拔样地年表之间相关性较差,且多不显著。样地年表的第1主分量能解释年表序列总方差的37.5%,反映了不同海拔高度岷江冷杉林木共同的径向生长变化格局;第2和第3主分量分别解释总方差的24.5%和18.2%,表现出明显的高海拔和低海拔样地树木间不同的径向生长变化,除一些样地例外,它们一般与低海拔样地年表有正相关,与高海拔样地年表有负相关。在那些另外的样地,海拔以外的其他因素可能也影响了树木径向生长变化。不同海拔高度样地林木的生长抑制和生长释放频率在不同时期表现出较大的差异,表明了不同的干扰历史和林木补充时间。 人工针叶林和次生混交林各样地林木早材宽度与其年轮总宽度年表之间相关系数均高达0.9以上;晚材宽度与年轮总宽度年表之间也都显著正相关,但人工针叶林样地的明显较高。样地年表序列之间的相关关系表现为,林分起源和经营管理相似的样地年表之间的相关系数明显较高,如人工针叶林与人工针叶林尽管树种不同,但样地年表之间显著正相关,而与次生混交林样地年表间关系不显著;反之亦然。综合比较各项生长参数及不同时期的树木径向生长速率,人工针叶林树木的胸径增长至少在40年以内是优于次生混交林的同种(或不同种)针叶树的。不同样地林木生长释放和生长抑制及人工针叶林树木胸高断面积增长分析表明,除严重的人为干扰外,林分郁闭后林木密度过大是造成高频率生长抑制的主要原因,在林分发育的适当时期通过抚育间伐等措施调控林分密度,是保证林木胸高断面积在一定时期内保持较高的连年增长的关键。日本落叶松作为引进的树种,在海拔3100 m左右种植表现良好,近30年来各项生长指标均高于林龄相近的云杉人工林,因此,适当用其作为川西亚高山针叶林采伐迹地快速恢复是合理的。 Miyaluo area is one of the typical regions covered by subalpine coniferous forests in western Sichuan province of southwestern China. To develop the regional tree-ring width chronology series for the dominant conifers such as Abies faxoniana, Picea asperata, P. purpurea and Larix potaninii, and to understand the radial growth patterns of conifers in Abies faxoniana natural forest stands at different altitudes, and in coniferous plantations and natural regenerated mixed stands in their different restoring processes as well, increment cores were sampled in the field together with conventional plots investigations for dendroecological analyses. After the increment cores being prepared according to standard procedures, the ring widths (total-ring and intra-ring widths) were measured with a WinDENDRO image-analysis system, and the measured tree-ring sequences were crossdated and quality-controlled with the software COFECHA. Using the software ARSTAN, we developed tree-ring width based chronology series of the four dominant conifers, eight site-specific Abies faxoniana chronologies, and seven site-specific chronologies of conifers in coniferous plantations and natural regenerated mixed stands. Mean sensitivities for total ring width chronologies of the four sampled dominant conifers were all below 0.2, while those for the latewood width chronologies of the same species were relatively much higher. Correlation coefficients between standard earlywood and total ring width chronologies of the four conifers were all above 0.9, but those between standard latewood and total ring width chronologies exhibited differences among species, with the coefficient of Larix potaninii the highest and that of Abies faxoniana the lowest. Correlation coefficients between latewood and total ring width of A. faxoniana obviously decreased from 1920-1970 for successive 50-year segments with 10-years lag analyses, though the same for the other three species changed unnoticeably with time. Tree-ring standard chronologies among species showed significant positive correlations, with the correlation coefficients between chronologies of Picea asperata and P. purpurea, and of Larix potaninii and Abies faxoniana relatively much higher. The first principal component of tree-ring chronologies represented the common radial growth patterns of the four conifers in Miyaluo area. The second, third and fourth PCs expressed the differences in radial growth responses for the genus Picea and Abies, for the evergreen and deciduous confers, and for the two species of the genus Picea, respectively. In general, mean sensitivities of the eight Abies faxoniana site-specific tree-ring width chronologies decreased with increasing altitude. The correlation coefficients between earlywood and total ring width chronologies for all sites reached 0.9, which did not change much with altitude; but those between latewood and total ring width chronologies diversified, with a decreasing tendency from lower altitudinal sites to higher altitudinal sites. Correlation coefficients among site chronologies varied considerably, with significant positive correlations among higher site chronologies, mixed results among lower site chronologies, and poor and insignificant correlations between chronologies of higher site and lower site. The first PC, which represents 37.5% of the total variance, reflected a common radial growth response at sites of different altitudes, and it showed a tendency of explaining more variance with increasing altitude. The second and the third PCs contributed to 24.5% and 18.2% of the total variance, respectively, exhibiting distinctive differences in radial growth responses between low- and high-altitudinal sites. With some exceptions, the radial growth represented by the second and third PCs had a positive correlation with that at the low-altitudinal sites and a negative correlation with that at the high-altitudinal sites. For those exceptional sites, factors other than altitude might also play a role in affecting tree-ring growth variations. Trees in stands of different altitudes showed great differences in frequencies of growth suppressions and releases through times, suggesting different disturbance histories and periods when trees recruiting to the canopy. Correlation coefficients between earlywood and total ring width chronologies for all sites of coniferous plantations and natural regenerated mixed stands were also above 0.9; and the same between latewood width and total ring width chronologies all positively correlated, too, with the coefficients of the coniferous plantations obviously much higher. Correlations among site chronologies showed that the coefficients among sites with similar stand origin and management regimes were much higher than those among sites with different stand origin and management regimes. For example, significant positive correlations were found for chronologies among different coniferous plantations, irrespective of species differences; while insignificant correlations between chronologies of the same conifer from a coniferous plantation and a natural regenerated mixed stand, and vise versa. Integrative comparisons of different tree growth parameters and radial growth rates at different stages indicated that the diameter at breast height (DBH) increments for trees in coniferous plantations were faster than those for trees of the same (or different) species in the natural regenerated mixed stands, at least within their first 40 years of stand development. Analyses of growth releases and suppressions, and basal area increments of trees in different stands demonstrated that over-dense individuals after canopy closure was the main factor resulting in high frequencies of radial growth suppressions, with some exceptions of severe man-made disturbances. Therefore, to ensure a continuous basal area current annual increment in certain periods, tree density controlling through thinning in due time during the stand development process are necessary. It should be mentioned that, as an introduced conifer to Miyaluo area, Larix kaempferi grew quite well at altitude of ca. 3100 m after planting in 1970s. In their near 30 years of stand development, Larix kaempferi trees exhibited faster growth in various parameters than Picea asperata trees of the similar stand age did. Thus we think it reasonable to use Larix kaempferi as a fast restoring species at appropriate sites of cutting blanks of subalpine coniferous forests in western Sichuan.
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对白水河自然保护区进行了生物多样性和植物区系调查,根据获得的生物多样性数据和标本的鉴定结果分析,得到结果和推论如下:1.白水河自然保护区生物多样性的垂直分布格局1.1 植物群落α 多样性随海拔梯度的变化乔木种的丰富度及多样性随海拔上升表现出明显的线性下降趋势。而灌木和草本物种丰富度及多样性随海拔上升表现出抛物线式的下降趋势。乔木种从海拔1400m 的15 种至林线时下降为2 种;灌木和草本植物分别从35 和38 种至山顶时下降为5 种和20 种。乔木物种随海拔升高出现明显的物种替代现象,表明海拔梯度包含了多种环境因子的梯度效应,影响着植物群落的分布与结构及物种多样性。1.2 植物群落β 多样性随海拔梯度的变化海拔2200 m 左右是一个明显的生境转折点。海拔2200 米以下相邻群落的相似性( CJ ) 明显大于海拔2200 m 以上的群落,说明海拔2200 m 以下的群落间共有种多,生境差异较小;而海拔2200 以上的群落则相反,相似性较低。低海拔区由于人为干扰较大,所以群落具有较高的物种丰富度,相邻群落之间的物种替换总量(Cody 指数) 较大。海拔2800 米到海拔3200 米之间因杜鹃群落的影响,物种替换总量(Cody 指数) 略有升高。研究β 多样性沿海拔梯度的变化必须考虑到物种丰富度和群落类型的影响,用不同指数从不同角度能更好地理解β 多样性沿环境梯度的变化。2.白水河自然保护区植物区系性质及起源白水河自然保护区自产种子植物计138 科421 属990 种。本文在科、属的水平上对该保护区植物区系特性进行了较深入的统计和分析。统计表明,温带和热带分布型均占有相当比重,但温带分布型稍占优势;热带、亚热带和温带的科、属多,中国特有属也有相当比例,它们是保护区具有特征意义的类群,其中许多属为古老和残遗成分。结论认为白水河保护区植物区系起源古老,较完好的保存了北极-第三纪古植物群。We have collected the specimens and gotten the biodiversity datas of BaiShuihe Nature Reserve in Peng Zhou,analysed the datas,the results as follows:1. Diversity of the plant community along altitudinal gradient1.1 α diversity of the plant communities along altitudinal gradientFrom 1400m to 3900m at Baishuihe Nature Reserve, 52 plots were investigatedwith an interval 100m in altitude; α diversity and β diversity of plant communitiesand their variety along altitudinal gradient were studied. The results showed that indifferent successional layers of trees, richness and diversity decreased linearly withthe increase of altitude. But shrub and herb layers don’t decrease linearly with theincrease of altitude. Tree species decreased from 15 species at 1400m so only 2species at timberline. Shrub and herb species decreased from 35 and 38 species at2000m to 5 and 20 species at 3800m respectively. Tree species are replacedobviously with the increase of altitude; It shows that altitude includes manyenvironmental facts, which infect the distribution, structure and diversity of plant population.1.2 The variety of βdiversity along altitudinal gradient.The entironment changed obviously near 2200m according to our research. Forsimilarity(CJ) between neighboring plots above 2200m is larger than wich below it.It shows that below 2200m,the neighboring plots has more same species,and thehabitats of neighboring plots has more similarity. Above 2200 is the other way round.The plant communites have higher species richness and species turnoverlargestly between neighboring plots because of the disturbance from humanity at lowaltitude. Between 2800m and 3200m species turnover not so obviously because ofmore Rhododendron live there.We should think over species and the types of plant communities effect thevariety of β diversity along altitude gradient. Use more biodiversity indexs and fromseveral aspects to understand the variety of β diversity along altitudinal gradient.2.Origin and characteristic features of Bai Shuihe Nature Reserve990 species of wild seed plants (belonging to 421 generas in 138 families) inthe floristic region of Bai Shuihe Nature Reserve were reported here. The statisticsand comparatively intensive analysis at generic and familiar levelss. Based on thestatistics,the results show that both temperate and tropical distribution types areacounted for considerable proportion of the total,but formal is a little moreimportant than the later. The North Temperate and E.Asia-N.America disjunctedpatterns are more concentrated in this area. These may be considered as thecharacteristic features of Bai Shuihe Nature Reserve flora, while many of them arearchaic and relic elements. According to above data,the floristic region of BaiShuihe Nature Reserve may be considered as a typical region in Chinese flora. Also,the flora of Bai Shuihe Nature Reserve are originated since ancient time as a wellconserved Arctic-Tertiar flora.
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小麦加工品质改良已成为我国小麦育种的主要目标之一。特别是我国加入WTO以后,对小麦产品的质量提出了更高的要求,小麦品质改良的任务将更加艰巨和重要,小麦胚乳蛋白是影响小麦加工品质性状的重要因素。因此,深入了解小麦胚乳蛋白对加工品质性状的影响及其分子基础,为品质改良提供理论依据和科学指导,对加速我国小麦品质育种和优质小麦生产具有重要意义。本研究选用在麦谷蛋白5个基因位点(Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3)上均含不同等位基因的小麦品种99G45和京771及Pm97034和京771杂交F9代共164个麦谷蛋白纯合系,及228个中国推广普通小麦品种和高代育成品系为试材,研究了麦谷蛋白Glu-1和Glu-3位点基因等位变异对籽粒蛋白、湿面筋含量、Zeleny沉降值和SDS沉降值间的关系;本研究还利用小麦A、B和D基因组中低分子量麦谷蛋白亚基(LMW-GS)基因特异引物,通过PCR方法克隆了1个Glu-A3位点和3个Glu-B3位点LMW-GS基因片段,在此基础上分析了不同等位基因对品质造成差异的分子基础;另外,本研究对中国近年推广的部分品种和育成的高代品系资源的多样性进行了分析。现将主要研究结果简述如下: 1. 对来自三个麦区的148份材料的醇溶蛋白组成进行了分析,结果表明,各麦区醇溶蛋白模式具有较大差异。在ω区,A7、B、E、F、G、J、P、Q、S和U仅存在于西南秋播麦区;A3、M、N、R、W和X仅存在于黄淮特种麦区;K仅存在于北方冬麦区;A6是北方冬麦区出现频率最高的带型模式,而西南秋播麦区中D出现的频率最高。ω-区的E、H和M几种模式是以前国内外未曾报道的。且初步确定,这些模式对品质性状具有正效应。至于γ区,A、B、D、E和F在各区均有出现,其中B和E在各区出现的频率都很高,在26.1-39.6%之间。相反,H 仅出现在黄淮特种麦区,J仅限于西南秋播麦区。对于β-区醇溶蛋白,B型模式在所有区中都相当高,而模式A仅存在于第三区.对于α-区,模式A在Ⅲ区而模式D在Ⅱ区出现的频率很高。1BL.1RS易位系在中国小麦品种中出现频率高达41.2%,在I, II和Ⅲ麦区的出现频率分别为 45.5、43.5和35.2%。各生态区模式的差异可能是品种适应不同生态条件和人为选择的结果,但这有待进一步证明。由于醇溶蛋白位点(Gli-1)与LMW-GS位点(Glu-3)紧密连锁,本结果可为下面确定普通小麦LMW-GS等位基因变异所用。 2. 利用Gli-1与Glu-3的紧密连锁,以228个小麦品种/系为材料,首次对中国小麦品种麦谷蛋白亚基的6个位点进行综合分析,研究小麦籽粒蛋白与品质性状间的关系,结果表明6个高分子量(HMW)和低分子量(LMW)麦谷蛋白位点对蛋白质含量的效应大小为,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3;对GMP含量的效应大小为, Glu-A3>Glu-B3>Glu-D1> Glu-B1>Glu-A1>Glu-D3;对湿面筋含量的效应大小为, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1;对Zeleny沉降值的效应大小为, Glu-A1> Glu-B3>Glu-D3>Glu-D1>Glu-B1>Glu-A3;对SDS沉降值的效应大小为, Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1。对蛋白含量而言,各位点的最佳组合方式为1、17+18、5+10、Glu-A3e、Glu-B3g、Glu-D3b;对湿面筋含量而言,各位点的最佳组合方式为1、6+8、5+10、Glu-A3d、Glu-B3c、Glu-D3b;对Zeleny沉降值而言,各位点的最佳组合方式为N、17+18、5+10、Glu-A3d、Glu-B3d、Glu-D3b;对SDS沉降值而言,各位点的最佳组合方式为1、7+8、2.2+12、Glu-A3b、Glu-B3g、Glu-D3b。另外,分析了稀有亚基对5+12与2.2+12与品质性状的关系,认为5+12对品质有负效应,2.2+12对品质有正效应。在品质育种时,应对优异组合或优异亚基加以利用。 3. 首次利用重组自交系(RILs)为材料,研究麦谷蛋白亚基表达量与品质性状的关系,通过对重组自交系中各HMW-GS表达量的分析,认为,就单个亚基的表达量而言,7亚基最高;其次为2亚基、5亚基、12亚基和10亚基;亚基9和1的表达量最小;N亚基不表达。对成对出现的亚基对而言,x型和y型亚基的总表达量2+12>5+10>7+9>17+18。就单个亚基与品质性状的关系而言,仅有10亚基的表达量与蛋白含量的相关性达5%的显著水平,2亚基的表达量与湿面筋含量呈负相关,显著水平也达5%,其余单个亚基对品质性状均无显著影响;就x型/y型亚基的比例来看,2/12和5/10对湿面筋含量都有显著的负效应;对某一位点等位基因控制的亚基表达总量来看,2+12对SDS沉降值有显著负效应。另外,本研究得出:2+12的亚基对的负效应主要体现在2亚基上,且在同一位点上,x型亚基的表达量大于y型。所以推导稀有亚基组合2+10很可能也是劣质亚基。 4. 以 Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3作为5个因素对99G45/京771和Pm97034/京771杂交后代的蛋白质含量和SDS沉降值进行多因素方差分析。结果表明,Glu-A1和Glu-D3对蛋白含量的加性效应达5%显著水平;Glu-D1 * Glu-D3对蛋白质含量的互作效应也达5%显著水平;其余位点的加性和互作效应对蛋白质含量的影响均不显著。对SDS 沉降值而言,Glu-D1的加性效应最大,贡献率为4.2 % ,达1 %显著水平,其次是Glu-B1位点,贡献率为3.3% ,达5%显著水平。其余位点对SDS 沉降值的加性和互作效应均未达5%显著水平。总体而言, 各位点对蛋白含量的效应大小为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3;对SDS沉降值的效应大小为Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。Glu-D1和Glu-D3位点上等位基因变异对蛋白含量有显著或极显著影响,含Glu-D1d和Glu-D3 GD、Glu-D3 JD基因的株系分别比含Glu-D1a和Glu-D3 PD基因的株系有较高的蛋白含量;在该遗传背景下,麦谷蛋白各基因位点对蛋白含量的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9>17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。对SDS沉降值的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9=17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。所以,对蛋白含量和SDS沉降值均较好的组合为1,7+9,5+10,GB,GD。 5. 因为GB和PB对品质的效应有显著差异,选取LMW-GS位点特异扩增引物对京771、99G45和Pm97034的Glu-B3位点进行扩增,结果得到三个不一样的扩增片段(Genebank号为DQ539657-DQ539659),得到的基因片段与Genebank中已报道的同类序列高度同源。通过克隆片段组成的分析,发现对Pm97034的序列较京771和99G45段少一个7氨基酸的重复单元,这可能是它较另外两个片段对面筋强度影响小的主要原因;另外,在99G45的序列中,124位处出现L(亮氨酸)代替P(脯氨酸),158位处出现了T(苏氨酸)代换M(蛋氨酸),这可能是99G45Glu-B3位点序列对SDS沉降值的效应显著优于Pm97034的原因。 6.通过对RILs各位点同普通小麦品种(系)各位点与品质关系的比较,发现对SDS沉降值的效应,各位点在不同研究材料中是不同的,普通小麦中:Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1,RILs中:Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。利用重组自交系材料(完全排除了1BL/1RS易位干扰)所得到的结果与Gupta and MacRitchie (1994)所得结论一致。进一步证实了1BL/1RS易位对小麦品质的重要影响。对蛋白含量而言,普通小麦品种(系)中,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3,RILs中,Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3,和对SDS沉降值的效应一样,推断在非1BL/1RS易位的情况下,各位点对其效应应为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3。 对同一位点的等位基因而言,普通小麦和重组自交系中Glu-A1和Glu-D1上的等位基因对品质性状的贡献是一致的,但Glu-B1上的等位基因对SDS沉降值的贡献发生了变化,普通小麦中17+18>7+9,RILs中7+9>17+18,这可能也是1BL/1RS造成的。 Baking quality improved is one of the main object of wheat bread in China. The overall objective of the present studies was to increase the understanding about protein quality in wheat, i.e. to make it possible to improve the production of wheat with desired quality for different end-uses. With the analysis of gluten protein in RILs, 99G45/Jing 771 and Pm97034/Jing, and 228 wheat cultivars or lines in China, the correlations between glutenin compositions and protein content, glutenin macropolymer(GMP), wet gluten content, Zeleny sedimentation value and SDS sedimentation value contentand breadmaking quality were studied. Also a rapid and efficient detection method of geneticpolymorphism at Glu-B3 loci in wheat was established using polymerase chain reaction(PCR).The results obtained were as follows: 1. Cultivated Chinese wheat germplasm has been a valuable genetic resource in international plant breeding. Patterns of gliadin among cultivated Chinese accessions are unknown, despite the proven value and potential novelty. The objective of this work was to analyse the diversity within improved Chinese wheat germplasm. The electrophoretic banding patterns of gliadin in common wheat cultivars and advanced lines were determined by acid-polyacrylamide gel electrophoresis. For 148 leading commercial cultivars and promising advanced lines used in our study, 48 patterns were identified, 29 corresponding to ω-gliadin, 9 to γ-gliadin, 5 to β-gliadin and 5 to α-gliadin. The most frequent patterns were A6 in ω; B in γ; B in β and A in the region of α. 116 band types appeared in the148 samples: 94 accessions had unique gliadin types, and 22 gliadin types while not unique were found in 54 accessions. The gliadin patterns of Chinese wheat cultivars and lines greatly differed from the patterns of wheat lines from other countries. Three patterns, E, J, H, M, N and O in the ω-zone had not previously been reported. Three wheat zones,the Northern Winter Wheat Region, the Yellow and Huai Valley River valleys Winter Wheat Region and the Southwestern Winter Wheat Region,in China showed different frequencies in their gliadin patterns. This information can be used to monitor genetic diversity with Chinese wheat germplasm. 2. To analyse the relationship between the loci and characteristics quality, we utilized the 228 cultivars/lines. The results showed that : For protein content, Glu-D1 >Glu-B3>Glu-A1=Glu-B1>Glu-A3=Glu-D3. For GMP content, Glu-A3>Glu-B3 >Glu-D1>Glu-B1>Glu-A1>Glu-D3. For wet gluten content, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1. For Zeleny sedimentation value, Glu-A1>Glu-B3> Glu-D3>Glu-D1>Glu-B1>Glu-A3, For SDS sedimentation value, Glu-B3>Glu-A1= Glu-D1= lu-A3>Glu-D3>Glu-B1。For protein content, the best combination of 6 loci is (1,17+18,5+10,Glu-A3e, Glu-B3g,Glu-D3b). For wet gluten content, the best combination of 6 loci is (1,6+8,5+10,Glu-A3d,Glu-B3c,Glu-D3b). For Zeleny sedimentation value, the best combination of 6 loci is (N,17+18,5+10,Glu-A3d, Glu-B3d, Glu-D3b). For SDS sedimentation value, the best combination of 6 loci is(7+8,2.2+12,Glu-A3b, Glu-B3g,Glu-D3b)。Additional, we analysed the relationship between the subunits 5+12 and 2.2+12, think that 5+12 was negative for quality, 2.2+12 is postive for quality. It should be effective utilized. 3. It’s the first time to utilize RILs to study the relationship between subunits expression quantity and characteristics quality. The results showed that: For single subunit, the expression quantity of 7 is the highest. Then the 2, 5, 12 and 10. The expression of subunit 9 and 1 is the lowest. Subunit N is not expressed. For subunits, the expression quantity of x type and y type are 2+12>5+10>7+9>17+18. The significant relation of 5% only showed between the expression quantity of subunit 10 and protein content. The relationship between expression quantity of others and characteristic quality was not significant. For x type/ytype, 2/12 and 5/10 is negative relation insignificant level. For the subunit(s) in a loci, Only 2+12 effect SDS sedimentation value negative in significant level. 4. With RILs 99G45/Jing 771 and Pm97034/Jing 771, we found that: The effective of Glu-A1, Glu-D3 and Glu-D1 * Glu-D3 for protein content is significant at 5% level. The effect of other loci for protein wre not significant. For SDS sedimentation value, the effect of Glu-D1is the highest, which contribution is 4.2 % .Then the Glu-B1, contribution is 3.3%. The effect of other loci for SDS sedimentationvalue were not significant. In total, for protein content: Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3; for SDS sedimentationvalue: Glu-D1>Glu-B1> Glu-D3>Glu-A1>Glu-B3. The effect of alleles in Glu-D1 and Glu-D3 loci are significant at 1% or 5%. In Glu-A1, 1>N; Glu-B1, 7+9>17+18>14+15; Glu-D, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. For SDS sedimentation, Glu-A1, 1>N; Glu-B1, 7+9=17+18>14+15; Glu-D1, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. The best combinations for SDS sedimentation value is 1,7+9,5+10,GB,GD. 5. Because of the difference of GB and PB for SDS sedimentation value, we selected the specific primer for LMW-GS loci to amplified the Glu-B3 of Jing771, 99G45and Pm97034. We got 3 amplify fragment (Gene Bank accession number are DQ539657-DQ539659). We found that the fragment of Pm97034 were deleted a repetitive 7 amino acid domain, which is perhaps the reason effect the gluten strength. Furthermore, in the position 124 of sequence 99G45, L has been replaced with P. Position 158, T replaced M, which may be the reason why the Glu-B3 locus of 99G45 is prefer to Pm97034 when refer to SDS sedimentation value. 6. Comparing the results of RILs and common wheat, we found that perhaps just the1BL/1RS made the difference of loci in different accession.
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This paper focuses on the concept of Integrated Coastal Management (ICM) putting the theoretical basis of Chapter 17, Agenda 21 (UN Conference on Environment and Development, UNCED), in relation to the theoretical backgrounds on which the development of coastal area programmes have been founded. Reasoning leads us to think that the general system theory is the proper conceptual basis to stimulate ICM and that, in this theoretical context, integration is to be pursued between (i) the claiming of national maritime jurisdictional belts and the protection of the coastal ecosystem, (ii) the coastal system and its external environment, (iii) the decision making systems acting at all levels (international, regional, national and local). Integration, therefore, should be thought of as a political process.
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陕北黄土丘陵沟壑区 ,生态环境脆弱 ,水土流失严重 ,作为环境脆弱带的山坡生产型道路 ,对加剧土壤侵蚀起着重要的作用 ,属等外路。人们并不很重视的山坡生产型道路却与农村生产运输、经济交流密切相关 ,其建设与维护具有重要意义。通过对延安黄土丘陵沟壑区山坡生产型道路侵蚀状况调查及对道路防蚀建设的经验 ,总结了现有山坡道路侵蚀现状、方式、影响因素 ,并从生物、工程两方面初步阐述防蚀措施的配置与设计
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In this contribution, we report a facile, gram-scale, low-cost route to prepare monodisperse superparamagnetic single-crystal magnetite NPs with mesoporous structure (MSSMN) via a very simple solvothermal method. The formation mechanism of MSSMN is also discussed and we think that Ostwald ripening probably plays an important role in this synthesis process. It is also interestingly found that the size and morphology of mesoporous Fe3O4 NPs can be easily controlled by changing the amount of NaOH and 1,2-ethylenediamine (ETH). Most importantly, the MSSMN can be used as an effective drug delivery carrier. A typical anticancer drug, doxorubicin (Dox), is used for drug loading, and the release behaviors of Dox in two different pH solutions are studied. The results indicate that the MSSMN has a high drug loading capacity and favorable release property for Dox; thus, it is very promising for the application in drug delivery.
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It is well known that the electrochemical oxidation of dopamine and ascorbic acid includes the proton and electron transfers at a glassy carbon electrode and their redox potentials are dependent on the pH of solution. When the concentration of the buffer is not enough to neutralize the protons produced by electrochemical oxidation of dopamine and ascorbic acid, two peaks of them can be observed in cyclic voltammograms. The height of the new peak is in proportion to the concentration of proton acceptor including HPO42-, 2,4,6-trimethylpyridine, tris (hydroxymethyl) aminomethane. Moreover, the potential of it is dependent on the type and the concentration of buffer at the same pH of bulk solution. However, this phenomenon cannot be attributed to the interaction between proton acceptor and dopamine or ascorbic acid. So, we think the phenomenon is caused by the acute change of pH at the surface of working electrode. Similar results were also observed in the rotating disk voltammograms. It can be concluded that the electrochemical behavior of some compounds is dependent on the concentration of buffer when this concentration is not enough to neutralize the protons produced in electrochemical oxidation.
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A new blue phosphorescent glass-ceramic, Eu2+ and Nd3+, co-doped CaO-Al2O3-B2O3, was synthesized. After the irradiation with ultraviolet (UV) light, the glass-ceramic emitted blue long-lasting phosphorescence (LLP) with a spectrum peaking at about 464 nm ascribed to the characteristic 4f(6)5d(1) -> 8S(7/2) transition of Eu2+. This phosphorescence can be seen in the dark 1 h after the irradiation. However, the transparent Eu2+ and Nd3+ co-doped CaO-Al2O3-B2O3 glass did not show the phosphorescence. By the X-ray diffraction diffusion (XRD) data, alpha-CaAl2B2O7 was demonstrated to be the crystallites in the glass-ceramic. We think that alpha-CaAl2B2O7:Eu2+ Nd3+ crystallites produced during the heat treatment of the glass contribute to the LLP of the glass-ceramic.
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We synthesized a series of polymers: poly(ether ether ketone ketone)(PEEKK), poly(ether biphenyl ether ketone ketone) (PEBEKK) and their copolymer by polycondensation, We also prepared a series of PEEKK-PEBEKK blends, By using DSC method, we found that T-g of the copolymers and the blends rose with the increasing of biphenyl contents in the polymers, T-c of the copolymers and the blends is higher than the corresponding homopolymer. From the results, we think that PEEKK-PEBEKK copolymer and blends are miscible and the copolymer is random.
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智能机器人技术在极地科学考察事业中有着广阔的应用前景。2007/2008年度第24次南极科学考察中,我国开发的冰雪面移动和低空飞行机器人在南极成功实现了首次应用。扼要介绍国外开发的应用于南极的智能机器人技术,重点介绍我国开发的冰雪面移动和低空飞行机器人及其在南极现场的试验应用情况。此外,作者思考了我国南极考察事业对智能机器人技术的一些潜在需求,以期能对未来的机器人技术开发提供参考。
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The exploration and study in recent years shows that the upper Paleozoic in the east of Ordos Basin possesses major exploration potential, so it is necessary to have a comprehensive and synthetic research in this area. Following the guideline of T.A. Cross’s high resolution sequences stratigraphy and combined with sedimentology, the strata and sequence in the research area are divided and correlated. This paper emphasizes on the reservoir in this area and its major fruits are: Firstly, form the framework of the high sequence stratigraphy through mainly studying on the data of core, well drilling and field section combining. Then, think that the best reservoir formation mainly appears in the middle or lower part of long arising semi-cycle, and focus on A type and C1 middle sequence cycle that contributes to the development of formation. Next, think the sedimentary source mainly comes from the epimetamorphic crystalline basement in the north of the Ordoes Basin through analyzing depositional background, researching on sandstone petrography, distribution characteristics of the sedimentary system as well as researching on heavy mineral combination characteristics. Fourthly, give priority to Zizhou-Qingjian area for the first time and gain seven lithofacies paleography maps in the No.2 member of Shanxi and the No.8 member of Shihezi through using the method of isochronal lithofacies paleogeography mapping, then bring forth that Sh2 is mainly developed a type I sequence under the margin of ramp lake-basin background. Fifthly, through researching on the characteristics of reservoir petrography and diagenesis, think that all researched areas experienced compaction and cementation, and there is different types of rocks, only little of the primary pores that are made up of litharenite and lithoclastic quartz sandstone is left, while in lithoclastic quartz sandstone, there are still many primary pores Sixthly, through studying on pore types, microstructure, as well as physical property on the key formation, think that the researched area mostly appears typical low pore, low porosity and permeability, which mainly result from sedimentary and diagenesis. Lastly, through researching on classified evaluation in the key formation, productivity analysis, and combing with reservoir distribution, the researched area is divided into three parts, and think that exploration should be emphasized on formation I and II. The characteristics of sandstones distribution in Sh23 member, gas formation distribution and open flow capacity of exploitation well are all consistent properly with the results of reservoir comprehensive evaluation in this thesis proved by the gas production development in 2006.
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Late Cenozoic has witnessed a series of climate-environmental change which ends with a transitional shift from greenhouse to icehouse conditions. In last two decades, scientists began to employ the tectonic uplift and its weathering effect to interpret the climatic changes during the late Cenozoic. However, this endeavor has partly been restricted by the lacking of regional and global chemical weathering data. The loess-red clay deposit in the Loess Plateau may record the weathering features of the detritus material from the wide range upwind of the Loess Plateau. Therefore geochemistry of the loess-plaeosol and red clay sequences may provide insights into the regional chemical weathering regime and the connection between the chemical weathering and the late Cenozoic climate-environmental change Here we selected 319 samples from the Baishui section near the Pingliang City, Gansu Province, and analyzed them with X-ray fluorescence. Based on the result, we reconstruct the chemical weathering history of the Baishui section since 6Ma. We chose CIA as the proxy for chemical weathering intensity. The CIA ratio in soil units is higher than in adjacent loess horizons, but lower than in the red clay, in good agreement with the field observation. The CIA ratios of the Baishui section correlates well with the global ice volume fluctuations, indicating that the global cooling may contribute a lot to the chemical weathering variations in Chinese Loess Plateau. There are at least 3 million-year time scale variations that can be identified in the chemical weathering intensity curve, i.e., between 3.3 to 2.1 Ma, 1.7 to 0.9 Ma and from 0.9Ma. We think these may reflect the combined effect of the tectonic uplift and ice sheets on monsoon intensity. Other time scale variations can be also observed. In the period between 2.4 and 0.8 Ma, the CIA record display the 400,000 years cycle, which may be resulted from the Tibetan uplift during the Pliocene-early Pleistocene which have significantly amplified the monsoon response sensitivity to the orbital-scale variations in insolation. From 1.2 Ma, the 100,000 years period became intensifying, and particularly after 0.8 Ma, the earlier monsoon response at 400,000 year periodicity was overwhelmed by the ice sheet forcing at 100,000 year periodicity. These may indicate that the expansions of the Northern Hemisphere ice sheets may have crossed a threshold, which enforce the monsoon responding at the 100,000 year periodicity.
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The seismic wide-angle reflection/refraction method is the one of the most effective method for probing the crustal and upper mantle structure. It mainly uses the wide-angle reflection information from the boundary in the crust and the top boundary of the upper mantle to rebuild the crust and upper mantle structure. Through analyzing the reflection and transmission coefficients of various incident waves on the interface, we think relative to the pre-critical angle reflection information the post critical angle reflection information that received by wide-angle seismic data exists a time-shift effect with the offset variation, and then it must cause the error for velocity analysis and structure image. The feature of the wide-angle seismic wave field of the fourteen representative crust columns tell us that the wide-angle effects in the different representative tectonic units for the interface depth and the interval velocity in crust. We studied the features of the wide-angle seismic wave field through building the crust model and inverse its travel time by GA method to know the wide-angle influence on crustal velocity image. At last we finished the data processing of the Tunxi-Wenzhou wide-angle seismic profile. The results are as following: (1) Through building crust model, we labeled the travel time for all the phases by ray tracing method and remove wide-angle effects method, it revealed the wide-angle effect exists in the seismic data. (2) The travel time inversion by GA method can tell us that the depth by traditional ray tracing method is shallower than the result by remove wide-angle effects method, the latter can recover the crust structure model in effect. (3) We applied the two method mentioned before to the fourteen representative crust columns in China. It indicates that the removed wide-angle effect method in travel time inversion is reasonable and effective. (4) The real data processing from Tunxi-Wenzhou wide-angle seismic profile give us the basic structure through the two ways. The main influence exhibits in the difference of the interval velocity of the curst, and the wide-angle effects in shallow interface are stronger than the deep interface.
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Xuanlong-type Hematite Deposits, distributed in Xuanhua and Longguang area in Hebei province and hosted in the Changchengian Chuanlinggou Formation of Mesoproterozoic, is an oldest depositional iron deposit characterized by oolitic and stromatolitic hematite and siderite. This thesis made an systematic study of its sedimentary, sedimentology, geochemistry, mineralogy and sequence stratigraphy. Based on above, the mechanism and background of biomineralization are discussed. There are four types of hematite ores including stromatolite, algal oolite, algal pisolite and oncolite. Based on detailed study on ore texture, the authors think both algal oolite and algal pisolite ores are organic texture ores, and related to the role of microorganisms. The process of blue-green algae and bacteria in the Xuanlong basin absorbing, adsorbing and sticking iron to build up stromatolite is the formation process of Xuanlong-type hematite deposit. Researches on ore-bearing series and ore geochemistry show that the enrichment of elements is closely related to the microorganism activities. Fe_2O_3 is enriched in dark laminations of stromatolite with much organic matter and SiO_2 in light laminations with detrital matters. The trace elements, especially biogenic elements, including V, P, Mo are enriched in ores but relatively low in country rocks. The paper also demonstrates on the sequence stratigraphy of hematite deposits and five sequences and twelve systems are divided. The characteristics of sequence stratigraphy show that the deposit-forming location has obviously selectivity and always exists under a transgressive setting. The oxygen isotope in hematite is about -2.2~5.7‰, which is similar to that of Hamlys iron formation of Australia but more negative than that of volcanic or hydrothermal iron deposits characterized by high positive values. The calculation by the result of oxygen isotope analysis shows that the temperature of ancient sea water was 48.53℃. The negative value of carbon isotope from siderite indicates its biogenic carbon source. Meanwhile, the occurrence of seismite in the ore-beds, which indicates the formation of hematite deposits is associated with frequent shock caused by structural movement such as distal volcano or ocean-bottom earthquake etc, show the occurrence of hematite deposits is eventual, not gradual. In shorts, Xuanlong-type hematite deposits were the result of interaction among geological setting of semi-isolated Xuanglong basin, favorable hot and humid climate condition, abundant iron source, microorganism such as algae and bateria as well as the fluctuation of the sea level.