Contribution of Different Processes in Wetland Soil N_2O Production in Different Restoration Phases of the Yellow River Estuary, China

采用时空替代法,选择黄河口生态恢复前后未恢复区(R_0)、2007年恢复区(R_(2007))和2002年恢复区(R_(2002))的芦苇湿地为研究对象,分析了生态恢复工程对湿地土壤N_2O产生不同过程与贡献的影响. 结果表明,尽管不同恢复阶段湿地土壤N_2O总产生量差异明显,但总体均表现为N_2O释放. 恢复区湿地土壤的N_2O产生量大于未恢复区. N_2O的产生主要以硝化作用和硝化细菌反硝化作用为主,而反硝化作用对N_2O的产生有较大削弱作用,这与不同恢复阶段湿地土壤理化性质密切相关. 非生物作用对N_2O产生量贡献较大,这与黄河口为高活性铁区,Fe的还原作用关系密切. 尽管黄河口不同恢复阶段湿地土壤N_2O的产生是生物作用与非生物作用共同作用的结果,但由于非生物作用对N_2O产生的影响较大,应受到特别关注. 温度和水分对不同恢复阶段湿地土壤N_2O产生过程的影响不尽一致,这与土壤微生物活性对温度和水分的响应差异有关. 黄河口不同恢复阶段湿地土壤的N_2O总产生量介于(0.37±0.08)~(9.75±7.64)nmol·(kg·h)~(-1),略高于闽江口互花米草湿地的N_2O总产生量,但明显低于富氧森林土壤、草原土壤和闽江口短叶茳芏湿地的N_2O总产生量. 研究发现,黄河口生态恢复工程的长期实施明显促进了N_2O的产生,因而下一步生态恢复工程应统筹考虑景观恢复与温室气体削弱这两方面因素

福建出口贸易发展与主要出口产品国际竞争力之研究

本文对福建省主要出口产品的国际竞争力进行研究,并对促进福建出口贸易发展的相关政策进行探讨。福建省对外经济贸易合作厅委托课题;; 福建省社会科学研究“十五”规划(第二期)项目(项目批准号:2003E172)的部分研究成

The Accounting Information on Network

网络的兴起与介入是新经济时代的一个明显特征 ,网络化经营正在成为当今经济活动中不可或缺的要素之一。网络化经济涉及到企业的经营战略、竞争能力和管理水平等方面的系统工程 ,也涉及到对会计信息系统的再认识和再建设。本文分析了网络经济的兴起及对会计信息的影响 ,指出了会计信息必须适应网络经济的趋势和要处理的几个关系The rise and popularization of the network has become a major characteristic of the age of New Economy.E-business is now becoming an elementary constituent in the business operations.E-business is not only a comprehensive system of business strategy,competence and management abilities of companies,but also relates to the recognition and re-construction of the accounting information systems.This article mainly focuses on the analysis of the implications about assounting information systems with the development of E-business,with a conclusion on the trend of an adaptation of accounting information system and the relevant relations which should be considered

Preliminary Study of Hangzhou Undergraduates Apartment Design

大学生人才公寓是国内近年发展起来的新建筑类型,是政府廉租房的一种具体形式。该文主要从总体规划和单体设计两方面,阐述了杭州大学毕业生人才公寓的设计过程,提出大学生人才公寓的规划设计应充分考虑年轻创业者的生活本质,提倡开放、交流、活力的新居住精神。The apartment of undergraduates is the new architectural type which has been developed in recent years, a kind of low rent houses by government. This paper mainly elaborates the design process of Hangzhou Undergraduates Apartment from the two aspects of general planning and architectural design. It brings forward the concept that Undergraduates Apartment design should take into young people's life essence consideration, and advocates the new housing concept of openness, communication and vitality

塔里木沙漠公路防护林生态工程的综合生态环境效应

为了探讨重大工程的生态环境效应,从风沙环境、土壤环境、小气候、生物多样性和地下水环境5个方面对塔里木沙漠公路防护林工程的综合生态环境效应进行了研究.结果表明:(1)防护林改变了近地表风沙运动过程,防沙体系内风速、输沙率降低幅度分别达64%~80%和87.45%~99.02%,风沙流结构、沙物质粒度、地表蚀积状况也发生了明显变化;(2)与自然流沙地相比,防护林土壤容重减小,全盐含量、总孔隙度和含水量增大,土壤肥力质量明显提高,其变化基本呈现"先快后慢"的规律;(3)防护林对于小环境改善作用明显,距地面6m范围内,林地不同高度的空气温度普遍低于自然流沙地,而空气湿度则高于自然流沙地,林地土壤温度也低于自然流沙地;(4)随着防护林内生境的变化,土壤微生物种类显著增加,但不同种类微生物的种群分布并不均匀;(5)目前防护林灌溉抽水对地下水位、地下水矿化度的影响不大,水位在厘米级范围波动,矿化度的变化幅度在±1g·L-1左右,且没有明显的变化趋势

Critical tidal level for planting Kandelia candel seedlings in Xiamen.

2003年5月在厦门大屿岛白鹭自然保护区西面滩涂上试种秋茄幼苗,研究秋茄的宜林临界线.结果表明,滩涂高程为黄零0.99m处,每个潮水周期的平均淹水时间高达8h,幼苗成活率低于50%,生长缓慢,不适合用秋茄造林;在滩涂高程为黄零1.62m处,秋茄幼苗成活率达90%,生物量积累最大,光合同化作用较高,生长良好,为厦门沿海秋茄的最适生长区;而在高程为黄零1.31m处,秋茄幼苗仍能正常生长.故厦门地区秋茄造林的宜林临界线应不低于黄零1.31m(即厦零4.55m),平均每个潮水周期淹水不高于5.6h.Plantable tidal flat is one of the most important factors affecting the survival rate of mangroves seedlings in forestation.In this paper,an experiment was conducted in the tidal zones of Umbrette Natural Reserve in the Dayu Island of Xiamen in May 2003 to investigate the critical tidal level for Kandelia candel forestation.The results showed that the tidal level of 0.99 m above the zero tidal level of the Huang Ocean was not suitable for planting K.candel seedlings,because the waterlogging time at this tidal level was longer than 8 h per-tide-cycle,and the survival rate was lower than 50%.At 1.62 m above the zero tidal level of Huang Ocean,K.candel seedlings had the best growth and the highest photosynthetic assimilation,with a survival rate of 90%.At 1.31 m above the zero tidal level of Huang Ocean,K.candel seedlings could still grow well.It could be concluded that the tidal level of 1.62 m was optimal for planting K.candel seedlings,and the critical tidal level of K.candel seedlings in the coastal areas of Xiamen was not lower than 1.31 m above the zero tidal level of Huang Ocean,where the waterlogging time was not longer than 5.6 h per-tide-cycle.国家自然科学基金项目(30200031);; 教育部博士点基金项目(20030384007);; 厦门市科技基金资助项目(3502Z20021046)

Contents and Structure Analysis of Tannins in Leaves of Three Cultivars of Camellia sinensis

测定了本山、黄旦和铁观音三个品种茶树成熟叶片的总酚及可溶缩合单宁含量,并通过基质辅助激光解吸附飞行时间质谱(MAldI-TOfMS)研究了茶叶缩合单宁的基本结构。结果显示,三种茶叶均具有较高的总酚含量,大约为200Mg/g;三种茶叶的缩合单宁是以(表)儿茶素(EC/C)和(表)棓儿茶素(EgC/gC)为基本结构单元的均聚物和杂聚物,且大部分聚合物的结构单元之间存在A型和b型两种连接方式,其中本山和黄旦缩合单宁的最高聚合度要大于铁观音。The contents of total polyphenols and extractable condensed tannins in leaves of three types of Camellia sinensis (Benshan,Huangdan and Tieguanyin) were determined.In addition,the structures of condensed tannins were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-Tof MS).Three types of tea leaves have total phenolic contents as high as 200 mg/g.The majority of condensed tannins in the three types of C.sinensis are identified as the mixtures of procyanidins and prodelphinidins with a medium level of galloylation through the linkage of A-type and B-type interflavan bonds.Meanwhile the degree of polymerizations is higher in Benshan and Huangdan than in Tieguanyin.国家自然科学基金项目(40376026;30671646

比较在时间缩放和俯仰平移算法中海明窗函数和布莱克曼窗函数的效果

实时变调过程被广泛用于各类音乐制作。变调技术可分为两大类:时间域类型和频域类型。在大规模变换计算方面频域法与时域方法相比更具有优势。然而,在频域处理使用傅里叶变换,导致不可避免的频率泄漏会影响音高转移效果的准确性。为了抑制傅立叶变换的副作用,窗函数被用于减低频谱混叠。在实际处理中,海明窗函数和布莱克曼窗函数经常使用。在本文中,我们比较了两个窗口函数在频率泄露的抑制方面的性能和精度

Construction of Normalized cDNA Library from Hepatopancreas of Abalone Haliotis diversicolor supertexta Exposure to Tributyltin

用rdP试剂提取三丁基锡暴露诱导的杂色鲍肝胰腺总rnA,经OlIgOTEX纯化得到MrnA;应用SMArT技术合成双链CdnA,双链特异核酸酶(dSn)进行双链CdnA的均一化,构建了杂色鲍三丁基锡暴露诱导下的均一化CdnA文库。原始文库的库容为4.3x106Cfu/Ml,重组率为97.9%。从文库中随机挑选了3288个克隆进行测序,得到3048个高质量EST序列,其中有370条COnTIgS,2103条SInglETS,unIgEnES共2473条,冗余率为18.86%。以上结果说明该文库质量较好,为进一步筛选相关功能基因打下基础;较低的冗余率说明该文库值得继续使用大规模ESTS测序的方法寻找相关功能基因,并为进一步使用基因芯片技术研究相关功能基因的表达谱提供便利。A normalized cDNA library from hepatopancreas of abalone Haliotis diversicolor supertexta exposure to Tributyltin was constructed.Total RNA were prepared using RDP reagent.Oligotex(QIAGEN)was used to separate the mRNA from total RNA.The first strand cDNA was synthesized by transcription of mRNA with the SMART technique.The LD-PCR was performed using a modified SMART primer as the primer set,and the first-strand cDNA as the template to synthesize double strand cDNA.Double strand cDNA was normalized using Duplex-Specific Nuclease(DSN).The containing capacity of the unamplified cDNA library was 4.3×106 CFU/ml with a recombinant rate of 97.9%.A total of 3 288 clones were random selected to be sequenced,and 3 048 high quality ESTs were generated.After processing,a total of 2 473 unigenes comprising 370 contigs and 2 103 singlets were obtained.The redundancy was 18.86%.These results indicate that the normalized cDNA library is suitable to be used for further cloning and analysis of genes related to tributyltin exposure.厦门市科技计划项目(3502Z20055024);国家自然科学基金(20877034);集美大学创新团队基金(2008A001

Measurement Method of Logical Gate in Bulk Spin Quantum Computer

提出一种核磁共振量子计算机两量子位逻辑门测量的方案。该方案通过设置适当的标记量子位可显著缩减测量所需输入态数目,给出量子门和具体输入状态集合的实验脉冲序列。包含较少J偶合演化的脉冲序列设计可有效减少操作时间,削弱环境对量子系统的退相干影响。A scheme of measuring two-qubit logical gate is proposed based on nuclear magnetic resonance,which includes the specific input states and complete pulse sequences.In comparison with the approach not using ancillary qubit,this method remarkably reduces the number of the inputs at the cost of flag qubit resource.The pulse sequence with fewer J-coupling evolution can effectively shorten the experiment time and weaken the quantum system decoherence effect by environment.福建省自然科学基金(2008J0219;2009J05152