17 research outputs found

    Phytohistochemistry on Developing Anthers of Houttuynia cordata

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    作者简介: 林美珍,女,硕士,副教授研究方向: 药用植物学, 通讯作者: 田惠桥,男,教授,博士生导师研究方向: 植物发育生殖学 Tel: ( 0592) 2186486 E-mail: hqtian@ xmu. edu. cn[中文文摘]目的揭示鱼腥草花药发育中营养成分的分布和转化特征。方法花药做半薄切片经植物组织化学染色后,进行显微观察。结果鱼腥草花药发育中,花药壁的表皮、药室内壁始终分布着一些淀粉颗粒;绒毡层细胞在小孢子母细胞时期出现了质壁分离的异常现象;成熟的花粉粒积累的脂类物质不丰富。结论花粉贮藏的营养物质是脂类物质,但不丰富,造成花粉粒败育。[英文文摘]OBJECTIVE To reveal the feature of distribution and conversion of the nutritional ingredients during anther development of Houttuynia cordata.METHODS Semithin sections of anthers by phytohistochemistry were observed under light-microscope.RESULTS Some starches distributed in epidermis and endothecium.Theabnormality of plasmolysis appeared in tapetal cells at the period of microspore mother cell.Lipids accumulation was not abundant in mature pollen grains during the anther development.CONCLUSION Pollen grains during the anther development.国家自然科学基金资助项目(30970275

    Molecular biological basis of salt tolerance in plants

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    植物分子水平的耐盐研究是近年的研究热点,通过综述与耐盐有关的几种重要分子的性质和作用,总结了几种与植物耐盐有关的基因以及它们在盐分胁迫下的表达和调控。 【英文摘要】 The research on salt resistance in plants at molecular levels has become a central issue in recent years.Present results focused on the characteristics and roles of some important molecules related to salt tolerance,and some important genes related to salt tolerance in plants and their expression and regulation in salt stress were discussed.国家自然科学基金资助项目(30271065);; 厦门大学新世纪优秀人才支持计划项目(0000-X07115

    A Comparative Study of Charge-Discharge Behaviors of α-PbO2 and β-PbO2 Cathodes

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    利用化学合成法分别制得α-PbO2和β-PbO2样品,采用XRD、SEM表征与观察两种不同晶型的PbO2样品. 由两种晶型PbO2粉末做成铅酸电池的活性正极,采用循环伏安、恒电流充放电以及电化学阻抗谱等电化学方法研究了其电化学性能. 结果表明,α-PbO2电极的放电容量较低,β-PbO2电极的放电容量较高,两种晶型PbO2粉末按不同配比制成复合电极有利于提高铅酸电池正极的充放电性能.The α-PbO2 and β-PbO2 powders were prepared using simple chemical synthetic methods, and their crystalline structures and surface morphologies were characterized with X-ray powder diffraction spectroscopy and scanning electron microscopy. Using the as-synthesized α-PbO2 and β-PbO2 powders as positive active materials, the electrochemical performance of the two PbO2 materials was investigated by means of cyclic voltammetry, galvanostatic charge-discharge tests, and electrochemical impedance spectroscopy. The results indicate that the discharge capacity of α-PbO2 electrode is larger than that of β-PbO2; moreover, the composite electrodes made by α-PbO2 and β-PbO2 mixtures with different proportions are favorable for enhancing the charge-discharge cycle performance of PbO2 positive electrode.国家973项目计划(No. 2011CB935901)和山东大学自主创新基金(No. 2009JC019)资助作者联系地址:1. 山东大学化学与化工学院,山东 济南 250100; 2. 山东圣阳电源股份有限公司,山东 曲阜 273100Author's Address: 1. School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China; 2. Shandong Sacred Sun Power Sources Co. LTD., Qufu 273100, Shandong, China通讯作者E-mail:[email protected]

    Status and assessment of PAHs pollution in surface sediment of mangrove areas in Jiulongjiang Estuary and neighboring harbors

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    作者简介: 陆志强( 1977~ ) , 男, 博士.[中文文摘]本文应用沉积物质量评价基准法对九龙江口及邻近港湾红树林区表层沉积物中多环芳烃的污染现状进行了生态风险评价,并定量分析了多环芳烃的相对污染强度.研究结果表明:各测站区多环芳烃相对污染系数均小于1,范围为0.022~0.620,污染程度尚属较低,引起生物毒性效应的几率相对较小.低分子量多环芳烃芴、萘和二氢苊占总相对污染系数比例较高(平均分别为18.1%、16.7%和15.3%),因而具有相对较高的潜在生态危害风险.[英文文摘]Based on Sediment Quality A ssessment Guidelines, the status and ecolog ical risk of PAH s pollution in surface sediment of mangrove areas in Jiulong jiang Estuary and neighboring harbors was assessed. With quant itative analysis of PAHs' relative contamination factor (RCF ), it was concluded that RCFs of PAHs in all sampling areas were ranging from 0.022 to 0.620, all less than 1. It suggested that the PAH s concentration in mangrove areas in Jiu long jiang Estuary and neighboring harbors was at relatively lower level ,indicating a lower incidence of adverse biological effects. Low mo lecu larw e ight PAHs such as fluorene, acenaphthene and naphthalene contribu ted higher percentage of RCF than the other PAHs, with average contributions of 18.1% , 16.7% and 15.3%, respectively. The results suggested a relatively higher potential ecological risk from low molecular weight PAH s.福建省自然科学基金资助项目(D002-0002);国家海洋局青年海洋科学基金资助项目(2004103

    新疆博斯腾湖湖周水体碳和盐离子的空间分布/Spatial Distributions of Organic Carbon and Dissolved Ions in the Bosten Lake, Xinjiang[J]

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    以博斯腾湖为研究对象,在大湖区周边及开都河取水样和表层土样,分析湖周水体中颗粒有机碳(POC)和溶解有机碳(DOC)在秋季的空间分布特征及其与周围土壤碳及水体盐离子的关系.结果表明:湖周水体中POC浓度的空间变化较大(0.1~1.2 mg·L-1),而DOC浓度的变化较小(8.5 ~12.3 mg·L-1).两者在出湖口和入湖口处的浓度均较低,与开都河的浓度相近.与早期相比,博斯腾湖水中无机碳存在由CO32-向HCO3-转化的现象.回归分析显示,水体中各形态碳与土壤碳之间没有显著的线性关系,表明水体中碳的含量受周围土壤的影响不大

    近30 a来开都河上游径流量变化的气候响应/Response of Runoff Volume to Climate Change in the Kaidu River Basin in Recent 30 Years[J]

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    利用巴音布鲁克水文站1980-2010年逐日径流量观测资料,采用线性趋势分析、多元回归分析等方法,研究了近30 a来开都河上游4-9月径流量的变化特征.同时,基于同期巴音布鲁克气象站气温、降水资料,探讨开都河上游气温与降水变化对春季径流量的影响.结果显示:开都河上游年径流量在过去30 a呈明显增加趋势.其中4-6月月平均径流量没有明显变化趋势,7-9月径流量增加明显.虽然年径流量主要分布在夏季,但年最大日径流量大多发生在春季4、5月份.进一步分析表明,前期冬季降水量与当年春季增温均对春季径流量有极显著的影响

    中国省际人口空间格局演化的分析方法与实证/Spatial pattern and its evolution of Chinese provincial population and empirical study[J]

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    中国正在经历着史无前例的城镇化过程,2011年全国城镇人口已达6.91亿人,城镇化率攀升至51.27%.按2030年城镇化水平到70%计算,还将有接近3亿人口从农村流动至城市.与此同时,由于总生育率受社会经济发展水平、生态环境以及社会思潮的共同作用,人口自然增长率正在减少,“单独二胎”政策即是国家对人口发展战略的重大战略调整.由此可见,对正处在城镇化、工业化和全球化加速推进的中国而言,人口自然增长与空间迁移正在且必将持续重塑人口空间格局,因而科学地认识中国人口自然增长和空间迁移的区域差异、准确地把握人口空间格局及其演化趋势,对于科学编制城镇化发展、土地利用、生态环境保护等各类空间规划和制订流动人口、区域协作等各项空间管理政策具有重要意义.本文构建了一种全新的自上而下的人口预测方法,考虑人口自然增长和空间迁移两种影响因素,着重对一级单元(全国)和次级单元(省级)在2010-2050年间的人口总量进行预测,并进一步研判我国人口空间格局的发展情景和演化特征:从各省人口密度变化来看,中国人口空间分布密度继续保持了东部高、中部次之、东北再次、西部最低的总体格局.东部省份中上海、北京、天津及江苏的人口密度始终保持在一至四位,最末三位依次是新疆、青海和西藏.根据本文提出的省际人口变化强度及其主导类型的测算指标和量化结果,可将中国划分为人口快速变化区(净迁入主导型、净迁出主导型、自然增长主导型)、人口低速变化区(净迁入型、净迁出型)以及人口平稳区.净迁入主导型人口快速变化区将吸纳99%的未来新增流动人口,其中上海、北京、浙江至2030年时人口密度达到顶峰,而广东的人口密度持续增加到2035年;净迁出主导型人口快速变化区,包括河南、安徽、重庆、湖北,75%的新增流动人口将由此类型区域迁出;辽宁和山东同属于自然增长主导型人口快速变化区,其新增流动人口比重极小,由人口自然增长变化主导区域的人口快速变化态势.在低速变化区中,除福建和海南作为少有的流动人口净迁入型省份,其余省份人口密度不断降低则缘于大量的劳动力输出和逐渐走低的生育率;大部西北和西南省份属于人口平稳区,其人口密度呈现出稳中有减的态势,人口密度平均值大多在100人/km2以下

    开都河流域上下游过去50a气温降水变化特征分析/Temperature and precipitation along the Kaidu River over the past 50 years[J]

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    利用开都河流域上下游4个气象台站(上游巴音布鲁克,下游焉耆、和静、和硕)1960 -2009年的气温、降水资料,采用趋势分析与距平等统计方法,分析了近50 a来开都河流域的主要气象要素变化特征.研究发现:(1)1960 -2009年开都河流域上下游年平均气温均呈明显上升趋势,增长强度分别为0.27℃/10 a和0.22℃/10 a.2000年后气温升高尤其显著,上游和下游的气温分别较50 a平均水平偏高0.97℃和0.69 ℃.该流域年最高温没有明显增加,而上下游年最低气温分别上升0.41℃/10 a和0.61℃/10 a,并与年平均气温有较好的相关性.通过对不同年代际各月气温的分析,发现该地区气温季节性特征在过去50 a发生了明显的变化.主要表现为冬季气温总体上升,夏季气温相对稳定,冬季与夏季温差逐渐减小,季节性呈变弱趋势.上游年代际间气温季节变化较下游更明显;(2)开都河流域降水主要集中在夏季,近50 a上下游降水量均呈增加趋势且上游达显著水平.上下游在降水分布及变化特征上有较大差异,上游年平均降水总量(273 mm)明显高于下游(77 mm),且上游降水量增加强度(9.13 mm/10 a)高于下游(5.34 mm/10 a).降水量年代际之间有一定差异,降水波动主要是在夏季,上游降水量的波动性大于下游

    芝麻酱感官词典的开发和建立Development and establishment of a sensory lexicon for sesame paste

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    为建立芝麻酱的感官词典,依据GB/T 16861—1997《感官分析 通过多元分析方法鉴定和选择用于建立感官剖面的描述词》产生芝麻酱的感官描述词,以几何平均值法分析删减描述词以制作芝麻酱感官风味轮,以相关性分析和主成分分析提炼关键性描述词,对关键性描述词添加定义、寻找参比样并进行强度赋值以形成芝麻酱关键性感官属性定量描述词汇表。结果显示,最终提炼20个关键性描述词(7个气味描述词,8个风味描述词,3个口感描述词,2个外观描述词)对芝麻酱感官特征进行定量描述分析。通过芝麻酱感官词典获得了不同芝麻酱的感官属性特征,且不同产地和焙炒条件芝麻酱的感官特征存在差异,这验证了芝麻酱感官词典的有效性。芝麻酱感官词典的开发为芝麻酱感官评价体系的建立提供了基础。In order to establish a sensory lexicon of sesame paste, the sensory descriptors for sesame paste were generated based on GB/T 16861-1997 Sensory analysis-indentification and selection of descriptors for establishing a sensory profile by a multidimensional approach was established. The descriptors were culled by applying the geometric mean method to create a sensory flavor wheel of sesame paste. The key descriptors were extracted by correlation analysis and principal component analysis. The key descriptors were defined, their reference samples were found, and their intensities were assigned to create the key sensory attributes quantitative descriptive lexicon of sesame paste. The results showed that 20 key descriptors (7 odor descriptors, 8 taste descriptors, 3 texture descriptors, and 2 appearance descriptors) were finally extracted to quantitatively describe the sensory characteristics of sesame paste. The sensory attributes characteristics of different sesame pastes were obtained by using the sesame paste sensory lexicon, and there were differences in the sensory characteristics among the sesame paste of different origins and different roasting conditions, which verified the validity of sensory lexicon for sesame paste. The development of the sensory lexicon for sesame paste can provide the basis for the establishment of a sensory evaluation system for sesame paste

    新疆博斯腾湖水体颗粒和溶解有机碳的季节变化及其来源初探/Seasonal variations and sources of particulate and dissolved organic carbon in Lake Bosten, Xinjiang Province[J]

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    在博斯腾湖选取了13个点位,于2012年5、8、10月测定表层和底层水体中的颗粒有机碳、溶解有机碳、颗粒有机氮和叶绿素a含量.结果显示颗粒和溶解有机碳在表层水体中的浓度与底层相近.博斯腾湖水体中颗粒有机碳的季节变化十分明显,其平均浓度从春季(0.64 mg/L)到夏季(0.71 mg/L)变化不大,但在秋季变化十分显著(浓度达1.58 mg/L).其中西北湖区和湖心区颗粒有机碳的季节变化最明显,东部湖区颗粒有机碳的季节变化相对较小.博斯腾湖水体的颗粒有机碳在春、秋两季主要来自外源输入,在夏季受水体中浮游生物的影响较大.博斯腾湖水体中溶解有机碳也具有一定的季节变化,夏季浓度(平均为9.3 mg/L)略低于春、秋两季(平均为10.3 mg/L).溶解有机碳在河口区的季节变化最强,其夏季浓度明显偏低,主要是由于开都河河水的稀释作用.总体上,博斯腾湖水体中溶解有机碳浓度的变化主要受外部因素的影响
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