Bioavailability of different forms of iron to Phaeodactylum tricornutum

铁是浮游植物进行光合作用和呼吸作用所必需的微量元素，直接参与硝酸盐及亚硝酸盐的还原、氮气的固定、叶绿素的合成等生物化学反应。铁的供应对浮游植物的生物量、生长率、种类组成和初级生产力有着重要影响。20世纪80年代，Martin等人的研究发现，一些海域虽然有足够的氮、磷等营养盐，浮游植物的生物量却很低，在这些海域加入适量的铁盐，能够促进浮游植物的生长。除了铁的浓度，铁的形态也会影响浮游植物的生长。因此，铁的浓度和形态对浮游植物生长的影响以及不同形态铁的生物可利用性，逐渐成为研究的热点。 三角褐指藻（Phaeodactylumtricornutum）属于硅藻门（Bacillariophyta），具...Iron is an essential trace element for phytoplankton, directly involved in many basic biochemical processes, such as photosynthesis, respiration, nitrate and nitrite reduction, nitrogen fixation, and chlorophyll synthesis. Iron supply has been suggested to have great influence on phytoplankton biomass, growth and species composition, as well as primary productivity. In the 1980s, Martin et al. fou...学位：理学硕士院系专业：环境与生态学院_环境科学学号：3312012115164

Information Environment,Comparability and the Accuracy of Revenue Plan

文章研究了公司的财务报表可比性是否影响营收计划的准确度,并考察两者之间的关系在不同的内部信息环境和外部信息环境下是否存在差异。文章研究发现:可比性越高的公司,其营收计划准确度越高;可比性与营收计划准确度之间的正向关系在较好的内部信息环境或较好的外部信息环境下更显著。研究结果说明可比性对营收计划准确度起到决定性作用,这一作用在较好的内外部信息环境下更强,这为提高我国上市公司营收计划的质量指明了方向。This study examines whether comparability of financial statement significantly improves the accuracy of revenue plan and investigates whether the above relationship is affected by the internal information environment and the external information environment.The results show that: the accounting information comparability is positively related to the accuracy of revenue plan; the positive relation between comparability of financial statement and the accuracy of revenue plan is more significant under the sound internal information environment or sound external information environment.These results suggest that comparability of financial statement is a determining factor affecting the accuracy of revenue plan,and the positive relationship is greatly influenced by the internal and external information environment,which provides a clear direction for improving the accuracy of revenue plan for listed companies in China.浙江省自然科学基金项目“我国上市公司营收计划披露的特征研究”(LQ14G020002); 国家自然科学基金项目“LLP转型、法律风险与审计行为研究”(71302060); 国家社会科学基金重点项目“公允价值信息采集及指数构建研究”(13AJY005); 浙江工商大学基金前期研究项目“我国上市公司营收计划披露特征的刻画研究”(1030KU114008

不同气氛下热处理对CO甲烷化催化剂性能的影响

采用液相包裹法制备了Ni/Al2O3耐高温甲烷化催化剂,并分别在静态空气、动态氮气及动态空气气氛条件下程序升温到550oC,恒温煅烧,得到不同气氛下热处理的三种催化剂。通过BET,H2-TPR,XPS等一系列的表征分析结果显示,经过动态气氛下煅烧的催化剂在高温和低温都具备良好的活性,其具有较大的比表面积,且流动性的气体可以有效的降低催化剂中镍与载体的结合力,主要表现在氧化镍的化学位能降低0.5eV,镍更易于还原

Catalytic Behaviors and Stability of Aerogel Silica-Supported Ni Catalysts for the Partial Oxidation of Methane into Synthesis Gas

以常压有机溶剂置换(A)和溶剂置换-表面改性(b)方式制备的两种SIO2气凝胶(SIO2-A(或b)型气凝胶,记为SIO2-A(Or b)g)为载体,采用常规浸渍法和聚乙烯吡咯烷酮(PVP)添加浸渍法合成不同SIO2气凝胶负载的nI/SIO2催化剂,并考察其催化的甲烷部分氧化(POM)制合成气的反应性能.结果表明,各催化剂的初始反应性能相近,但nI/SIO2-bg的POM稳定性明显较nI/SIO2-Ag的差,而PVP添加制备的催化剂稳定性则获明显改善,nI/SIO2-Ag-PVP、nI/SIO2-bg-PVP上POM稳定性相近.结合X射线衍射(Xrd)、程序升温还原反应(H2-TPr)、高分辨透射电镜(TEM)和brunAuEr-EMMETT-TEllEr(bET)等表征结果的分析发现:(1)SIO2-Ag表面上存在一定量的羟基,可促进亲水性金属物种与其的相互作用,而SIO2-bg表面上基本为有机基团,与亲水性金属物种几乎无作用;(2)PVP的存在可使金属物种进入亲/疏水载体孔道深处,抑制焙烧中载体骨架的收缩和金属颗粒的生长,进而促进金属载体的相互作用.这二者均能有效地提高催化剂的POM反应稳定性.Two types of aerogel silica,denoted as SiO2- A(or B)G are synthesized with either solvent substitution(A) or solvent substitution-surface modification(B) under atmospheric conditions.Aerogel silicasupported Ni catalysts are then prepared via impregnated(IM) and polyvinylpyrrolidone(PVP)-added IM methods,and their performances for the partial oxidation of methane(POM) are investigated.The similar initial catalytic performances(activity and selectivity) are observed over the different Ni/SiO2catalysts.With respect to POM stability,Ni/SiO2-BG is significantly worse than Ni/SiO2-AG,while catalysts with PVP addition(during preparation) exhibit a significant improvement.In this case,Ni/SiO2-BG-PVP is comparable to Ni/SiO2-AG-PVP.We characterize the catalysts with X-ray diffraction(XRD),temperature-programmed hydrogen reduction(H2-TPR),transmission electron microscopy(TEM),and Brunauer-Emmett-Teller(BET) analysis.We find that there are hydroxyls on the SiO2-AG surface that favor their interaction with hydrophilic metal species,while on the SiO2-BG surface there are organic groups that do not interact with hydrophilic metal species.In addition,with the help of PVP,metal species can access the deep pores of hydrophilic/hydrophobic silica gels.Then,the contraction of the silica framework and the growth of metal particles are inhibited during calcinations,enhancing interactions between Ni and the silica gels.These(benefits from surface hydroxyls and PVP) result in significant improvements in the catalysts with respect to POM stability.国家重点基础研究发展计划(973)(2010CB732303); 国家自然科学基金(21033006;21373169); 长江学者和创新团队发展计划(IRT1036)资助~

良渚遺跡群の研究

良渚囲壁は東西南北の4面にそれぞれ2門が開く構造であることが判明した。内外両側に環濠を配しており、いわゆる水城の様相を呈している。囲壁内部のほぼ中央に位置する莫角山土台の基底部に積まれた「土嚢」の年代測定から、莫角山の建造が紀元前2900年前後にまでさかのぼることが確認された。遺跡群西方では崗公嶺地点を初め何か所かでダム状遺構が検出されており、これまた紀元前3000年頃に位置づけられる。塘山土塁とともに複雑な水利施設群を構成していたことが明らかとなった。Liangzhu enclosure is rectangular in shape and each side has two gates. The wall is accompanied by inner and outer moats, so it may have seemed like a ‘floating city’. Mojiaoshan platform, which is located at the center of the enclosure, is dated back to around 2900BC from the carbon-14 dating of the sandbags of vegetable matter piled near the bottom of the platform. To the west of Liangzhu site groups, some dam-like earthen structures have been found such as Ganggongling site and they are also dated back to 3000BC. It is clear they consisted complicated hydraulic facilities together with Tnagshan rampart.出典：研究課題「中国における都市の生成: 良渚遺跡群の学際的総合研究 / Urban Genesis in China: Multidisciplinary Study of Liangzhu Site Groups」課題番号22251010（KAKEN：科学研究費助成事業データベース（国立情報学研究所））（https://kaken.nii.ac.jp/report/KAKENHI-PROJECT-22251010/22251010seika/）著者版報告書の全文を掲載、報告書目次を再掲

Improvement in synthesis method of 4-hydroxycoumarin

考察以邻羟基苯乙酮与碳酸二乙酯为原料反应合成4-羟基香豆素的新方法。通过正交实验对相转移催化剂添加量、碱性缩合剂用量、加料温度、反应时间进行考察,得出此方法合成4-羟基香豆素的较优工艺条件为:原料摩尔比为n(邻羟基苯乙酮):n(碳酸二乙酯):n(甲醇钠):n(聚乙二醇-400)=1:2:3.0:0.42,在5~10℃温度下加料,120℃反应2.5 H,收率为65.7%。产物经熔点、Ir、--1HnMr、--(13)CnMr进行鉴定。4-Hydroxycoumarin was synthesized by the reaction of 2-hydroxyacetophenone with diethyl carbonate via the catalyst of sodium methoxide and polyethylene glycol-400.According to the orthogonal design experiments about the dosages of polyethylene glycol-400,the dosages of alkali,the feed temperture and the reaction time.The optimal reaction conditions were as follows:xylene as the solvent,n(2-hydroxyacetophenone):n(diethyl carbonate):n(sodium methoxide):n(polyethylene glycol-400) = 1:2.0:3.0:0.42.Feed under the temperature of 5—10℃.The reaction mixture was heated at 120℃for 2.5 h.4-Hydroxycoumarin was produced in 65.7%yield.The product was characterized by Melting point meter,IR,--1HNMR and --(13)CNMR

OBS中支持QoS的增强型自适应偏置时间算法

在基于恰量时间（Just-Enough-Time,JET）信令的无光缓存光突发交换（OBS）网络中,根据网络负载和服务质量（QoS）要求灵活进行偏置时间（Offset Time,OT）设置的问题,文章提出了一种使用增强型学习机制计算OT的算法,使得OT能够随着网络载荷的变化进行自适应调整,并能支持QoS,从而能较好地适应网络状态的变化。仿真结果表明,该算法可以在不同的网络状态下有效地降低端到端的延迟和阻塞率,并能很好地提供QoS服务

MOTION PLANNING FOR MOBILE ROBOT BASED ON REAL TIME OBSTACLE PREDICTION

本文给出了移动机器人的虚力导航和运动规划系统．这种方法结合最小方差估计算法（ＬＭ ＳＥ）能有效地对机器人进行实时导航和避撞．在预测过程中，根据导航的不同阶段和预测误差的变化情况，采用Ｆｕｚｚｙ 规则动态地调整误差函数中的权重，使预测过程尽可能准确．导航算法的基本思想是首先通过预测算法来获得移动机器人的运动信息，然后虚力系统根据预测信息决定机器人的未来运动，仿真结果表明该方法实时性好，能准确躲避障碍物并且到达目标