38 resultados para 3.500.073

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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在历史旱涝记载资料可靠性检验的基础上,重建了湖北省3个区域近500年来的干湿气候变化序列,并比较分析了各区域干湿气候变化的趋势特征、准周期性及跃变现象。结果表明:在3个区域中,鄂东区1570~1770、1890~1950年两个时段偏湿,1470~1520、1790~1830年则偏干;鄂北区偏湿时期主要在1470~1530、1710~1750、1850~1910年三个时段,1470~1530、1770~1830年则偏干;鄂西南区有1550~1610、1650~1710、1830~1890、1930~1990

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本文综述了日冕瞬变现象的主要观测特征及其理论模型.日冕瞬变是从太阳日冕中向行星际空间大量抛出物质的过程,每次事件可有5×10~(15)克的物质在10~3秒的时间内以约500公里/秒的典型速度被驱动流到日球中.日冕瞬变与太阳耀斑和爆发日珥事件有密切的相关性.作为一种新的太阳活动现象,近年来对日冕瞬变提出了许多理论解释.一种数值模拟方法将瞬变看成是由于热力学量或磁力在日冕底部的脉冲增长所产生的结果.许多分析模型认为是由磁环内部的电磁力或外部的磁压力驱动所致,或者是环中磁浮力驱动的结果.考虑到瞬变与耀斑和爆发日珥的相关性,活塞驱动模型认为,瞬变是稠密等离子体喷射,像活塞驱动机制.观测和理论都有待于进一步的研究.

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植物远缘杂交是作物育种实践及其相关的基础遗传中应用最广泛的技术之一,几乎涉及到所有与栽培作物有关的科属内相对近缘的植物种类。除核型稳定的种间杂交可得到杂种外,还可以利用核型不稳定的种间杂交过程中父本染色体全部被消除的现象,通过胚培养和加倍处理获得大量的双单倍体(DH)杂交后代。然而,这种从小麦与玉米杂交获得的小麦DH后代与其理论上应完全同质的遗传表现却不相符,总有2-5%的DH植株发生了形态学变异,虽然没有明显的来自玉米的性状特征,而且一些研究者也认为它们是配子无性系变异,但是,不论是理论上还是一些间接的细胞学和生化证据都表明,有玉米的染色体DNA通过受精过程转移到小麦DH后代的基因组中,然而到目前为止,仍缺乏DNA水平上的直接证据。 本文在对来自小麦 * 玉米的谱通小麦DH系进行生化分析取得初步证据的基础上,构建玉米的随机基因组文库,从中筛选玉米的重复DNA序列作探针分别对普通小麦和波斯小麦的DH群体进行了系统的RFLP分析,并用有关的玉米重复列克隆对一些禾本科种和不同的玉米生物型基因组进行了比较研究,主要结果如下: 1、八种同工酶电泳分析表明,MDH、ADH、GDH、SKDH4种脱氢酶和GOT在后代中没有检测到任何变异,但21株普通小麦的DH后代群体中有7株在PER同工酶的慢区出现了增加一条酶带的变异,这条带在亲本小麦和玉米中均没有,它们与通常报道的无性系变异十分类似。其中有一株(第4号株)在迁移率为0.22的位置上出现了一条小麦所不具有的酶活性较强的EST带,在玉米同迁移率的位置上也有一条带,但活性十分微弱。此外,大部分小麦DH后代的AMY同工酶恬性有十分明显的增强。 2、可溶性蛋白质的SDS-PAGE分析,在小麦的DH后代中,有几株的变异很明显,其中第4、7、19号株(图2)在分子量为43000道尔顿的位置上出现了和玉米同迁移率而小麦不具有的蛋白质带,这强烈地暗示了玉米DNA的确通过受精作用导入小麦。 3、构建了玉米的随机基因组文库,依据菌落原位杂交结果,从中挑出了500个重组克隆。用其中的100个强信号的重复DNA克隆为探针对亲本小麦和玉米进行了RFLP筛选,其中80多个为玉米基因组特异的,9个与小麦有部分同源性,随后用它们探针分别对两个小麦DH群体进行RFLP分析。 4、用上文筛选的玉米特异的重复DNA克隆作探针进行RFLP分析,只有玉米的MR64克隆同时导入到两个小麦群体的各一株后代中,即普通小麦DH系的18号株和波斯小麦DH系的15号株检测到强杂交信号;另外一个克隆MR72只在4株波斯小麦DH后代中有杂交信号,这个结果首次从DNA水平上证明,的确有某些玉米特异的DNA序列通过受精作用以很低的频率转移到小麦DH后代的基因组中。 5、与小麦有部分同源性的玉米克隆MR13和MR50在一些普通小麦DH后代中检测到了缺失变异。特别是用MR13在普通小麦DH系的18号株(即导入了玉米特异的MR64的DNA的那一株小麦DH后代)的基因组中检测到了大幅度的限制性片段长度的变化,即原来的4.3kb的强信号带消失了,取而代之的是增加40kb、15kb、2.5kb和2.0kb四条杂交带,这要么与小麦基因组DNA较大的重俳事件有关,要么是由外源的玉米DNA插入造成的,但从增加的片段长度如此之大以及杂交信号变弱来看,它很可能就是玉米DNA插入到这个较强信号的小麦单拷贝序列中的结果。用小麦的DNA克隆pTa71也检测到了明显的变异。 6、测序分析发现,克隆MP64的插入片段长度为695bp,A+T含量为58%,经在GENEBANK中检索证实它是一个新克隆的DNA序列。序列中分别含有两对正向和反向重 序列及三个回文序列,对多种酶切的玉米基因组的RFLP分析表明它是一个带1-3个主串联重复单位的散布重复序列,在序列中的CCGG的第二个C高度甲基化,拷贝数约为5600左右。染色体原位杂交表明,MR64在玉米的每条染色体上均有分布,但拷贝数不同,这暗示它可能与玉米基因组的演化历程有密切的关系。 7、比较分析发现,MR64是玉米基因组特异的;而MR72在高粱、珍株粟、糜子和狼尾草等四个和玉米较近缘的种的基因组中有部分同源序列,这个比较结果更加肯定了小麦DH系所新增的DNA序列的确是异源的玉米DNA通过受精过程导入的。 8、初步分析发现,玉米的卫星DNA克隆MR4和其它卫星DNA一样也有严谨的重复等级结构,而且在主要禾本科种基因组中有较低的同源性。经在GENEBANK检索,串联重复DNA克隆MR68是一个新克隆的DNA序列,它在不同的玉米生物型基因组中表现出明显的分化特征,可用它作进一步的基因组的比较分析。 9、本文对染色体消除过程度中异源小片段DNA导入的可能机制和散布重复序列在远缘杂交的异源DNA鉴定中的应用进行了讨论,并分析了染色体消除型远缘杂交所获得的DH后代的变异来源。

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By impairing both function and survival, the severe reduction in oxygen availability associated with high-altitude environments is likely to act as an agent of natural selection. We used genomic and candidate gene approaches to search for evidence of such genetic selection. First, a genome-wide allelic differentiation scan (GWADS) comparing indigenous highlanders of the Tibetan Plateau (3,200 3,500 m) with closely related lowland Han revealed a genome-wide significant divergence across eight SNPs located near EPAS1. This gene encodes the transcription factor HIF2 alpha, which stimulates production of red blood cells and thus increases the concentration of hemoglobin in blood. Second, in a separate cohort of Tibetans residing at 4,200 m, we identified 31 EPAS1 SNPs in high linkage disequilibrium that correlated significantly with hemoglobin concentration. The sex-adjusted hemoglobin concentration was, on average, 0.8 g/dL lower in the major allele homozygotes compared with the heterozygotes. These findings were replicated in a third cohort of Tibetans residing at 4,300 m. The alleles associating with lower hemoglobin concentrations were correlated with the signal from the GWADS study and were observed at greatly elevated frequencies in the Tibetan cohorts compared with the Han. High hemoglobin concentrations are a cardinal feature of chronic mountain sickness offering one plausible mechanism for selection. Alternatively, as EPAS1 is pleiotropic in its effects, selection may have operated on some other aspect of the phenotype. Whichever of these explanations is correct, the evidence for genetic selection at the EPAS1 locus from the GWADS study is supported by the replicated studies associating function with the allelic variants.

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本研究通过我国CDBI、 KUN、PE、SZ等主要标本馆约3, 500份馆藏标本的研究和野外考察相结合,对我国蔷薇属(Rosa L.)芹叶组(Sect. pimpinellifoliae DC. ex Ser.)植物以及相关组的一些种进行了性状特征、形态和微形态的研究,对该组的一些种的形态特征描述进行了补充,同时给出详细的地理和海拔范围分布图。综合花粉以及种子(瘦果)形态的研究结果重新制订了分种检索表,同时,对该组一些形态相近容易混淆的种进行了对比研究,特别对一直存在争议的绢毛复合体(绢毛蔷薇R. sericea Lindl.和峨眉蔷薇R. omeiensis Rolfe)进行了大量宏观形态特征的研究,并用光学显微镜(LM)和扫描电镜(SEM)对二者的花粉及种子形态、微形态进行对比研究和分析,主要研究内容包括: 1. 芹叶组孢粉研究 对芹叶组的10个种及相关的4个组共17个种(18个样品)的植物花粉进行了光镜和扫描电镜观察和比较研究。研究结果表明:蔷薇属植物花粉粒大小为中等偏小,极轴长23.98[21.82(R. graciliflora Rehd. et Wils.)~29.18(R. tsinglingensis Pax. et Hoffm.)] μm,赤道轴长28.65[24.15(R. graciliflora)~34.70(R. davidii Crép.)] μm;花粉属辐射对称等极单花粉,花粉形态赤道面观呈球形到超长球形;极面观为三裂圆形或近圆形,三孔沟,孔缘加厚,具中部突起的桥状盖。花粉外壁纹饰为条纹状,光镜下形态特征相差不大;在电镜下外壁条纹和脊沟内穿孔的形状、大小和频度等特征,常具组至种水平上的可见变异,可作为组至种水平划分的依据。 根据花粉外壁条纹特征及穿孔形状和数目等特征,本研究将这些植物的花粉归为5个类型,并编制了分组检索表。同时,根据条纹状的清晰度,排列方式、条纹形状、穿孔大小及其频度等方面的差异,各有特点,对该组的10个种编制了分种检索表。 2. 芹叶组种子形态研究 应用光学显微镜和扫描电镜对我国蔷薇属芹叶组14个种及相关组5个组共36种植物的种子宏观形态及种皮微形态特征进行了观察研究。结果显示,蔷薇属种子形态多样,形状分别为肾形、卵形或锥形等;种子颜色以淡棕色、褐色以及土黄色为主;种子大小种间相差悬殊,相对体积为(长×宽×厚)36.66(4.79~114.47) mm3。光镜下,种子宏观形态特征具组内一致性,在扫描电镜下种子表面结构特征因种而异,其纹饰以网纹为主,可分为3种类型,即近平滑型、负网纹型和网纹型。研究结果表明,蔷薇属种子表面纹饰与地理分布关系不大,具有组及种内稳定性。其种子形态、大小、表而纹饰类型等特征可作为蔷薇属组及种水平上的分类依据。 结合蔷薇属花粉形态研究结果,得出蔷薇属种皮微形态特征与花粉外壁纹饰特征相吻合,在代表组及种的特征上具相关性的结论。同时根据种子形态、微形态结构特征的组间区别和种间差异编制了分组及芹叶组14个种的分种检索表。 3. 绢毛蔷薇复合体的研究 通过对大量标本的研究、野外观察以及扫描电镜对绢毛蔷薇复合体的花粉形态和种皮表面结构进行研究,通过对小叶、花粉及种子的形态定量分析结果支持Rowley (1959)的观点,将峨眉蔷薇处理为绢毛蔷薇的一个变种。 综上研究结果得出,蔷薇属植物的小叶片数目、花被基数以及花粉及种子形态等性状是较为稳定的,这些特征可很好的作为分类学依据。 The morphology, pollen exine sculpture and seed coat structure of the species of Rosa sect. Pimpinellifoliae and related sections were studied.About 3,500 herbarium specimens at CDBI, KUN, PE, and SZ were examined. Field work in Sichuan and Yunnan were conducted. Revisions of some species were carried out and a new key to species of sect. Pimpinellifoliae was proposed based on morphology, pollen exine sculpture and seed coat structure, Detailed morphological descriptions, geographical distributions and the altitudinal ranges of some taxa are given. The systematics of the species complex, the Rosa sericea complex (R. sericea Lindl. & R. omeiensis Rolfe), was emphasized. This thesis focused on the following three aspects: 1. Pollen morphology of Rosa sect. Pimpinellifoliae The pollen morphology of 18 samples representing 10 species of the Eurasian Rosa sect. Pimpinellifoliae and 7 additional species of related sections was investigated under LM and SEM. The pollen grains are monadic, actinomorphic, equipolar, medium-sized, spheroidal to perprolate in equatorial view, 3-lobed circular or semi-circular in polar view, crassimarginate, pontoperculate, and with striate exine sculpture. The striate sculpture varies among sections and species. The equatorial axis ranges from 17.97 μm (R. sikangensis) to 29.18 μm (R. tsinglingensis) with an average of 23.98 μm in length, while polar axis varies from 24.15 μm (R. gracilifolra) to 34.70 μm (R. davidii) with an average of 28.65 μm in length. The pollens can be divided into five types based on striate sculpture and a key to the sections sampled was proposed accordingly. The pollen morphology of species of sect. Pimpinellifoliae is more homogeneous and different from other sections sampled and did not support the two-series subdivisions in sect. Pimpinellifoliae. A key is also provided based on characers of pollen morphology among species in sect. Pimpinellifoliae. 2. Seed coat structure of Rosa sect. Pimpinellifoliae The seed coat structure of 39 samples representing 14 species of Rosa sect. Pimpinellifoliae and 12 additional species of related sections was investigated under LE and SEM. The seed relative volume (Length × width × thickness) ranges from 4.79 to 114.47 mm3 with an average of 36.66. mm3. The seeds are reniform, ovate or oblong in shape, with orange-brown, light brown or deep brown color. Seed coat sculpture was reticulate or striate-like reticulate. There was no difference in sculpture character of various speices under LM, while three types of seed coat sculpture were identified under SEM and a key to species based on the seed coat sculpture was provided. The three types of seed coat sculpture were nearly smooth, areolate and reticulate. The study of the seed coat sculpture of same species sampled from different populations showed that characters on the seed coat are stable, and thus the size, shape and seed coat sculpture can be used in species level identification. Interestingly, characters in the seed coat sculpture and the pollen morphology in sect. Pimpinellifoliae are consistent at in specific or sectional levels. A key to the 14 species sampled was given based on seed coat sculpture. 3. The study on Rosa sericea complex The Rosa sericea complex contains R. omeiensis and R. sericea. They are morphologically similar to one another and the systematic status of R. omeiensis has been controversial. In this study we examined large numbers of herbarium specimens of R. omeiensis and R. sericea and conducted field observations in the Hengduan Mts.. We also performed SEM study of pollen morphology and seed coat structure of R. omeiensis and R. sericea. We further carried out intensive morphometric study on the leaflet, pollen, and seed morphology. Our results showed that R. omeiensis should be sunk to be a variety of R. sericea, just as Rowley’s treatment in 1959. In conclusion, the features in the number of leaflet and petal, and the morphological character on pollen and seed are relatively stable. Therefore these characters are very useful in taxon delimition.

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制革行业是轻工行业中仅次于造纸业的高耗水、重污染行业,作为劳动密集型行业,在解决大量人口就业问题的同时,也对所在地区环境造成了严重污染。目前我国制革行业每年排放废水8,000~12,000万吨,废水中含铬约3,500 t,SS为1.2×105 t,COD为1.8×105 t,BOD为7×104 t,对水体污染严重。 本研究在对厌氧酸化工艺进行研究、一级好氧处理段进行工艺比选研究的基础上,获得了匀质调节—SBBR—BAF的生物处理工艺,并依托该工艺进行了生物强化处理的研究,考察了菌剂的强化运行效果及其处理水回用的可行性。 研究表明,在进水COD>3,000 mg/L,厌氧酸化具有很好的抗冲击作用,保证了好氧工艺出水COD<200 mg/L;在进水COD<3,000 mg/L,可只通过好氧处理实现出水COD<200 mg/L。厌氧酸化停留时间选择不当,会导致厌氧出水硫化物浓度升高,严重影响好氧系统,会使好氧活性污泥因中毒而解絮。 研究表明,当进水COD为2,000~2,500 mg/L,NH4+-N为130~146 mg/L时,COD、NH4+-N去除率SBBR分别为93.8%~96.6%和14.5%~55.9%,SBR分别为88.8%~94.9%和13%~50.7%,表明SBBR优于SBR。同时,研究发现SBBR污泥增长率为0.05 kgVSS/kgCOD,仅为SBR0.57 kgVSS/kgCOD的8.8%。此外,研究发现SBBR在停止运行后经3个运行周期可回复原油能力,而SBR池经9个周期培养也不能恢复,说明SBBR恢复能力明显优于SBR。 研究表明,以匀质调节—SBBR—BAF为主的制革废水处理工艺,出水水质稳定,进水COD 801~2,834 mg/L、NH4+-N 87~203 mg/L,出水COD<80 mg/L、NH4+-N<10 mg/L,基本达到中水回用标准;操作简单灵活,没有污泥回流系统,污泥产率低,污泥处理费用低;工艺基本不需要添加化学药剂,既节约成本、又避免了二次污染;两级生物膜使得该工艺具有很强的耐冲击负荷能力,特别适合制革废水水质水量波动大的特点。 研究表明,高效菌对系统的启动具有一定的促进作用,强化系统生物膜6天可以成熟,对照系统生物膜9天可以成熟。同时高效菌能加速COD降解,缩短停留时间,强化系统6~8 h可使COD<200 mg/L,对照系统8~10 h可使COD<200 mg/L。长期运行表明,强化系统的SBBR在COD和NH4+-N的去除率都优于对照系统的SBBR。最终出水COD强化系统平均为53 mg/L、对照系统为74 mg/L。在模拟循环过程中,强化系统均有更高的稳定性。可实现8次理论循环,而对照系统只能实现4次理论循环。 研究表明,通过合理的工艺设计,可以实现猪皮制革废水达到《污水综合排放标准GB8976-1996》一级标准,同时满足工厂部分用水要求。通过添加高效微生物,可提高生物处理系统处理能力,使处理水能够满足工厂的多次回用。 As a labour-intensive industry, tanning has created large amount of working opportunities as well as caused severe contamination to environment. And it is one of the highest water-consuming and polluting industry, only second to manufacturing. At present time, Chinese leather industry emits wastewater about 80,000,000~120,000,000 t annually, which contains chromium about 3,500 t, SS 1.2×105 t, COD 1.8×105 t, BOD 7×104 t and ambient riverhead has been polluted greatly. Based on the research of anaerobic acidification and comparison of SBBR and SBR, biotreatment process (Homogenization—SBBR—BAF) had been established to amend the disadvantages of traditional sewage treatment such as too much sludge, high cost of advanced treatment and NH4+-N can not reach the emission standard. Research on the bioaugmentation was also been carried out. Researches showed, when COD of influent was beyond 3,000 mg/L, anaerobic acidification could resist strong impact, thus COD of effluent was less than 200 mg/L; when COD of influent was less than 3,000 mg/L, only throughout aerobic sewage treatment could COD of effluent beless than 200 mg/L. False residence tiome of anaerobic acidification would lead to the higher effluent concentration of sulfide and disintegration of aerobic activated sludge. Researches showed SBBR worked a better than SBR: when influent between 2,000 and 2,500 mg/L, NH4+-N between 130 mg/L and 146 mg/L, COD, NH4+-N removal rate of SBBR was 93.3%~96.6%, 14.5%~55.9% respectively while COD, NH4+-N removal rate of SBR was 88.8%~94.9%, 13%~50.7% respectively. Sludge growth rate of SBBR was 8.8% of that of 0.05 kgVSS/kgCOD. Besides, SBBR could recovered after 3 operating periods while SBR worked no better after 9 operating periods.Therefore, SBBR excelled SBR. Researches showed, effluent quantity of tannery wastewater treatment process (Homogenization—SBBR—BAF) was stable. When COD of influent was between 801 and 2,834 mg/L, NH4+-N was between 87 mg/L and 203 mg/L, COD of effluent was less than 80 mg/L, NH4+-N was less than 10 mg/L, which achieved the standard of reuse. This biotreatment was featured in low cost, easy and flexible management, less sludge, no inverse sludge system. Besides, this technique required no chemical, which could lower the cost and avoid secondary pollution. Great resistant of impact due to two membranes and was suitable for tannery wastewater which was featured by fluctuation of influent quality and quantity. Researches showed effective microorganisms promotes the startup of the process.Biofilm in the bioaugmentation process matured with 6 days while biofilm in normal process matured with 9 days. Effective microorganisms could accelerate the degradation of COD and shorten the residence time. Aggrandizement system could make COD<200 mg/L with 6 to8 hours while cntrolling system could make COD<200 mg/L with 8 to 10 hours. Long-term operating shows that SBBR in the bioaugmentation system worked better than the normal system in the treatment of COD and NH4+-N. The average COC of effluent in bioaugmentation system was 53 mg/L, normal system was 74 mg/L. In the simulative circulation process,aggrandizement process, which could fulfill 8 times theoretical circulation, works more stably than controlling process which could only fulfill 4 times theoretical circulation. Researches showed that reasonable design could make the wastewater meet the first grade of discharging standard of National Integrated Wastewater Discharge Standard (GB8976-1996), and partially meet the demand of water using of the factory. Adding effective microorganisms could enhance the biotreatment and make the effluents reuse many times.

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研究结果表明不同坡度谷子地 ,高 N处理小区径流中铵态氮、硝态氮和有效氮浓度平均为 1.0 6、0 .76和1.82 mg/kg,低 N分别为 0 .6 4、1.2 9和 1.93mg/kg;高氮处理土壤铵态氮、硝态氮和有效氮平均流失量分别达到17.90、12 .93和 30 .84kg/(km2 · a) ,低 N流失量为 11.90、2 3.86和 35 .77kg/(km2 · a)。高氮处理小区泥沙中有机质和全氮浓度平均为 5 .2 1和 0 .5 36 g/kg,而低氮处理分别为 4.94和 0 .481g/kg;高氮和低氮处理土壤有机质流失量分别为 5 70 2和 5 743kg/(km2 · a) ,土壤全氮流失量为 498和 5 5 9kg/(km2 · a)

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本文利用顺磁稀土离子的诱导化学位移变化的性质,研究了多官能团配体谷胱甘肽(GSH)与稀土的配位作用.在水溶液中GSH通过分子两端的羧基负离子与稀土形成遥爪配位结构.谷氨酸端和甘氨酸端羧基与Eu~(3+)的配位稳定常数分别为12.5±0.1L/mol和100.0±0.5L/mol.从~(13)C化学位移的pH变化曲线求得谷氨酸端和甘氨酸端羧基解离的pK_a值分别为2.20±0.02和3.50±0.04.对Dy~(3+)、Ho~(3+)、Er~(3+)、Tm~(3+)和 Yb~(3+)作用下,GSH的~(13)C位移数据分析表明,配体与这些离子形成同构的配合物,分子两端羧基均可能以双齿形式与稀土配位.

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本文利用美国国家环境预测中心和国家大气研究中心(NCEP/NCAR—National Centers for Environmental Prediction/National Center for Atmospheric Research)的位势高度、气温、风速等大气资料、欧洲中期天气预报中心 (ECMWF—European Centre for Medium-Range Weather Forecasts—ERA-40)的雪深资料、美国国家海洋大气管理局(NOAA—National Oceanic and Atmospheric Administration)的海表温度(SST)资料、美国Scripps海洋研究所的上层海洋热含量资料等,采取相关分析、合成分析、经验正交函数分析、小波分析和小波交叉谱分析等统计分析方法,系统深入地讨论了西太平洋—印度洋—青藏高原气候系统在南海夏季风爆发过程中的作用。得到的主要结论如下: 1. 西太平洋和印度洋在南海夏季风爆发过程中起着关键作用 利用1951-1998年多种大气海洋资料,分析研究结果表明,西太平洋(暖池热含量)、印度洋(纬向风)在南海夏季风爆发中起关键的调控作用:以1970年为界,1970年之前,印度洋起主要作用,1970年之后西太平洋起主要作用,这主要是1970前后北极涛动有明显跃变的原因,这种跃变决定了印度洋在南海夏季风爆发中是否起决定作用(西风异常或东风异常),进而,决定了有利于或不利于南海夏季风的爆发。 1970年之前,北极涛动指数为负值,海陆温差(海上气温减大陆气温)是负值,大陆气温偏高,印度洋气温相对偏低,印度洋出现西风异常,有利于南海夏季风早爆发。在此期间,与印度洋SST密切相关的南印度洋偶极子的变化也与南海夏季风的爆发紧密相联。当南印度洋为正偶极子(西南印度洋SST为正异常,印度洋其他区域的SST为负异常)时,北印度洋为西风异常,南海夏季风爆发偏早;南印度洋为负偶极子(西南印度洋SST为负异常,印度洋其他地区的SST为正异常)时,北印度洋为东风异常,南海夏季风爆发偏晚。 1970年之后,北极涛动指数为正值,海陆气温差为正值,印度洋的状态不利于南海季风爆发;在这种情况下,西太平洋暖池的热含量则成为控制南海夏季风爆发的主要原因:暖池变暖的年份,即 La Niña 年,南海夏季风爆发早(强),反之,当暖池变冷的年份,即El Niño年,南海季风爆发晚(弱),即,南海夏季风爆发的早(强)晚(弱)与ENSO事件密切相关。 2.青藏高原春季积雪对南海夏季风爆发有重要的影响 1958-2003年青藏高原3月积雪厚度与南海夏季风爆发时间存在着很好的正相关。青藏高原3月积雪厚度偏厚时,其500毫巴以上的气温偏低,上层海陆之间的气温差是正值,南亚高压向西北方向的移动速度变慢,上层东风偏弱,西太平洋地区的上层辐散和下层辐合变弱,西太平洋暖池热含量偏少,南海夏季风爆发偏晚(弱)。同时,下层850毫巴东印度洋异常大气是东风和跨赤道反气旋对,南海被东风异常所控制,这种大气环流形势不利于南海夏季风的爆发;青藏高原3月积雪厚度偏薄时,其500毫巴以上的气温偏高,上层海陆之间的气温差是负值,上层南亚高压在南亚地区建立较早,上层东风偏强,西太平洋地区的上层辐散和下层辐合偏强,西太平洋暖池热含量偏多,南海夏季风爆发偏早(强)。同时,下层850毫巴东印度洋低层大气是西风异常和跨赤道气旋对,南海被西南风异常所控制,有利于南海夏季风的爆发。 研究结果还表明,青藏高原春季的积雪与厄尔尼诺事件存在着密切的关系。在厄尔尼诺鼎盛期的冬季,各种条件都有利于青藏高原的降雪,从而,来年春天的积雪则变厚,不利于南海季风的爆发。 3. 南海夏季风爆发的预测 1970年之后,西太平洋暖池的热含量与南海夏季风的爆发早晚有非常好的负相关。据此,我们可以通过西太平洋暖池热含量的变化来预测南海夏季风的爆发。通过暖池区海洋上层400米热含量的分析研究,我们找到了西太平洋暖池热含量变化的代表站点(以3N,138E为中心的1°×1°范围),其热含量变化能很好代表整个西太平洋暖池热含量的变化(相关系数大于0.85)。在此基础上,文章用1993-2007年热带大气海洋浮标列阵(TAO-Tropical Atmosphere Ocean-array)中最靠近该站点的浮标(2N, 137E)资料验证了上述选择站点的代表性和相应的预测能力。1993-2004年TAO浮标(2N, 137E)3月上层400米和500米海洋热含量与南海夏季风爆发时间的相关系数分别是-0.75,-0.73,置信度均超过99%;用1993-2007年4月份TAO浮标(2N, 137E)上层400米和500米海洋热含量与南海夏季风爆发时间作相关则相关系数均为-0.83,置信度超过99%。因此,我们可以通过3月或者4月份该TAO浮标(2N, 137E)的热含量来预测当年南海夏季风爆发的早(强)晚(弱)。 总之,南海夏季风爆发以1970年为界存在明显的年代际变化,1970年之前,主要受印度洋控制,1970年之后,南海夏季风爆发主要受控于太平洋(西太平洋暖池),这种变化是由北极涛动年代际变化引起的,。青藏高原春季积雪也对南海夏季风有重要影响,但主要受ENSO控制。因此,我们认为西太平洋—印度洋—青藏高原气候系统在南海夏季风爆发中起着重要的调控作用:西太平洋的作用当属第一位,印度洋的作用居第二,青藏高原的作用最弱。

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以馆养北太平洋宽吻海豚为研究对象,在海豚馆和水族馆等场所开展了大量的现场实验和行为学研究;通过出海考察、“调查卡”统计、整理历史资料等方式,总结了中国海洋哺乳动物的资源现状,并对我国典型海域中的海洋哺乳动物标本通过目前较为先进的中子活化(INAA)等技术进行了一系列的分析研究。主要结果如下: 1通过对海豚馆的先后10头海豚进行的长达5年的现场实验,首次提出并建立了适合海豚生长的水质标准体系,其中,盐度范围是29-32,PH值范围是7.8-8.2,氯浓度范围是0.3—1.5mg/L,溶解氧范围为5.0—8.8×10~(-6),大肠菌群不超过200MPN等等,这为国内各地海兽馆中的海兽饲养提供了参照标准,为我国海兽饲养业的发展提供了可靠的基础资料。2 通过对海豚的每一批饵料鱼体营养成分的测定分析(粗蛋白、粗脂肪、灰分、水分和总细菌数),进而通过对海豚的食性、日食量及食前反应、食后反应等方面的研究,发现了海豚的季节性饮食喜好规律,即海豚在冬天喜欢采食鲐鱼等高能量型鱼类,在夏天喜1欢采食带鱼等低能量型鱼类,首次建立了海豚的饵料投喂、营养补充物质的适量添加及定期进行驱虫、接种疫苗和体格检查等科学饲养管理方法体系。3通过对北太平洋宽吻海豚进行的500余头次的生理指标的测定(直接获得有关数据9000多个),在国内首次建立了多头宽吻海豚的生理指标档案和数据库,主要包括血常规指标、血液生化指标、体温、呼吸频率等45个指标。4在宽吻海豚生理指标档案和数据库基础上,运用了适当的计算方法,结合相应的生理学意义,统计归纳出了宽吻海豚各生理指标的正常阈值和范围,如白细胞的正常阈值为3.797×10~9个/L-11.56×10~9个/L等等,此生理指标阈值范围体系是准确了解海豚机体的生理状况、疾病诊断及治疗的关键依据。5 发现了海豚各生理指标间的相关关系及生理指标与海豚疾病诊断间的关系规律,基本形成了宽吻海豚常见疾病的诊断和防治方法体系,如海豚血液指标中的K~+值降低,白蛋白与球蛋白比值 (A/G)下降,表明海豚机体脱水,电解质代谢紊乱;海豚血液中 的谷草转氨酶、谷丙转氨酶大幅升高,中性粒细胞值上升,胆红素值升高,表明海豚的肝脏功能异常等等。其中,治愈铜绿假单孢菌感染经查新属国际领先水平。6 总结了中国海洋哺乳动物的资源现状,并通过中子活化技术、等离子体耦合原子发射谱技术和原子发射谱技术,对日本下关海豚、秦皇岛海豚、莱州湾海豚和秦皇岛江豚的肌肉、肝脏、肾脏、心脏和肺等样品进行了多元素的测定分析,测出了其中的27种元素的含量,初步建立了中国海洋哺乳动物环境标本库。7 通过对所测海洋哺乳动物器官样品中的元素含量的比较,发现海洋哺乳动物的不同器官富集元素的能力明显不同,各器官的富集能力基本是肝脏 > 肾脏 > 心脏 > 肺 > 肌肉,海兽肌肉不适合作为环境标本库的样品,而肝脏和肾脏较为适合作为海洋哺乳动物环境标本库的样品。8 所测海兽器官样品中的大多元素的含量值与阿拉斯加环境标本库的结果相似,只有Zn、Cu、Pb和Hg的含量远远高于阿拉斯加环境标本库的结果,而与中国人体肝脏的相应元素的含量基本相似。日本下关海豚肝脏中的Cd、Co、Cr、Cu、Pb、V和Zn元素的含量高于秦皇岛海豚和莱州湾海豚肝脏中对应元素的含量,而秦皇岛海豚肝脏中的As、Cu、和Ni的含量又高于莱州湾海豚肝脏中的相应元素的含量。

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根据笔者实测的青海高原高寒地区300余种植物稳定性碳同位素比值(δ13C)以及参阅已经发表过的国内外不同地区的C4植物名录,整理出青海高原高寒地区3 500余种植物中的C4植物.得出青海高原高寒地区共有9科32属的52种植物属于C4植物,禾本科(Gramineae)18属24种,藜科(Chenopodiaceae)9属20种,苋科(Amaranthaceae)1属4种,菊科(Compositae)2属3种,大戟科(Euphorbiaceae)、蒺藜科(Zygophyllaceae)、旋花科(Convolvulaceae)、景天科(Crassulaceae)、眼子菜科(Potamogetonaceae)各1属1种.同时归纳了52种C4植物的生活型以及地理分布区.

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South China Sea is located in the convergence of Eurasian plate, the Pacific Ocean plate and Indian Ocean-Australia plate. The total area is about 3,500,000 km2, the geologic structure is complicated, and the structure line cut off reciprocal is the marginal sea taking form by that the seafloor spreads during the middle Oligocene. South China Sea continental margin have developed more than 10 large oil-gas bearing basins and a number of medium-small sized basins. These basins contain abundant mineral resources such as oil & gas. The marginal deepwater area in the north part of South China Sea has become our country’s strategic energy prospecting frontier. The deepwater area of Zhujiangkou and Qiongdongnan basins is the research target in this thesis. The thesis studied deep structure and the earth dynamics of the north part of South China Sea margin, and these researches provide scientific basis for oil-gas resources strategic investigation and valuation in deepwater sea area of north part slope of South China Sea. In order to develop the research of rebuilding velocities and density architecture of earth shell in region of interest, in marginal deepwater area in the north part of South China, we adopted 14 long-cable seismic reflection profile data of 3556.41 kilometers in total, the gravity measurement data along profiles (3851.44 kilometers in total), the magnetic observation along profiles (3838.4 kilometers in total) and depth measurement along profile, the logging data of 11 wells in project, the interpreted fault parameter and preexisting geologic and geophysical research achievement. This thesis has carried out concretely studying research as follows: 1. Overlay-velocity data sampling and analysis, interval velocity calculation, time-depth conversion, model building of earth shell velocity and layering character of earth shell are studied on 14 deep sections. Velocity structure in region of interest has revealed: Changchang is the sag with thinnest crust in Qiongdongnan basin; the sedimentary thickness lowers gradually from north to south, and the thickness change from west to east is milder. The sags’ sedimentary velocities in Qiongdongnan basin have obvious demarcation. The velocity of the 8000 meters sedimentary rocks is 4700 m/s in Shunde sag and Baiyun sag, and is the lowest; at that depth, the velocity very different in Liwan sag and Baiyun sag, which is about 800m/s. 2. Extracting gravity data and building of initial crust density model along the section; With Bouguer gravity anomaly data as constraint, revising density distributes of initial model, and building the crust density model. 3. With crust velocity and density as constraint, correcting the effect of thermobaric field and constructing constitution structure of rock in region of interest. By this research, we known that rocks in Zhujiangkou upper crustal layer are chiefly granite-gneiss, quartzite, granodiorite and basalt, however, rocks in Qiongdongnan basin upper earth shell are chiefly composed of granite-gneiss, quartzite, granodiorite, diorite and basalt. 4. Synthetically crust velocity and density structure, gaining expanding factor on crust and entire crust along section. The result is indicated: the expanding factor in every sag rises from northwest to southeast, which have reflected thinning characteristic of crust from continent to ocean. Intra-crustal deformation degree in Changchang and Ledong-Lingshui sag is bigger than that in Songnan-Baodao sag. Entire crust extension factor in Changchang and Songnan-Baodao sag is greater than that in Ledong-Lingshui sag, which can make an explanation of frequently event and longer heating process in middle-east of Qiongdongnan basin. 5. Synthesize multidisciplinary information to discuss the earth dynamics significance of discordogenic seismic profile in deepwater area of Zhujiangkou and Qiongdongnan basins.

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The Multifactor Leadership theory developed by Bass (1985) has become the new paradigm of leadership research. The empirical results of the effectiveness of transformational and transactional leadership in the literature, however, are not consentient. Researchers in China found the different structure of transformational leadership, but have not developed the transactional leadership. This study attempts to investigate three key questions in the unique Chinese socio-economic context: 1) what is the structure of transactional leadership in China? 2) What are the differences between western countries and China? And 3) what is the relationship between the transformational and transactional leadership mechanism? This study examines data collected from 3,500 participants, using Explored Factor Analysis (EFA), Confirmed Factor Analysis (CFA), Hierarchical Regression Analyses, partial correlations and other statistics methods. The major finings are listed as follows: Firstly, inductive methods was used to explore the structure of transactional leadership and the result show that transactional leadership is a four dimensions structure which includes contingent reward, contingent punishment , process control and anticipated investment. Reliability analysis, item analysis, EFA and CFA show the reliability and validity of the transactional leadership questionnaire we designed is good enough, the design of the item is effectively and properly. Contrast to other researches, anticipated investment emphasis on the leader’s recessive investment for subordinate, and this kind of transaction is quite special under the Chinese culture. While the content of the contingent reward with the contingent punishment is wider than the contingent reward in the western country, and the process control is wider than the management by exception and including goal setting and the management during the process. Secondly, hierarchical regression analyses showed that transformational and transactional leadership were significant positively related with in-role performance, extra-role performance, satisfaction and leadership effectiveness while negatively related to intention to leave. The effects of transactional and transformational leadership are different. Transactional leadership could significantly predict intention to leave controlling for transformational leadership, while transformational leadership could significantly predict in-role performance, extra-role performance, satisfaction and leadership effectiveness controlling for transactional leadership. Thirdly, the income level and the rank of subordinates are the moderators between the transformational, transactional leadership and leadership effectiveness. The leadership effectiveness of transactional leadership would decrease as the rank of subordinates increased, while the leadership effectiveness of transformational leadership would increase as the rank of subordinates increased. Transactional leadership is positively related to the effectiveness when the level of the subordinate income is low, but negatively related to the effectiveness when the level of the subordinate income is high. However the income level of the subordinate could not influence the leadership effectiveness of transformational leadership.