225 research outputs found

    Separation and Identification of β-alanine in Sargassum horneri(Turn.) C.Ag.

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    非蛋白质氨基酸在抗癌、抗菌、抗结核、抗坏血病等方面有着重要的作用。本文主要对铜藻中的游离氨基酸进行检测分析和部分分离纯化及结构鉴定方面的研究,为更好的开发利用这些天然产物提供技术支持。采用离子交换树脂层析法分离铜藻粗提液中的游离氨基酸,收集3 MOl/l的氨水洗脱液,用PITC-HPlC柱前衍生反相高效液相色谱法对其进行检测分析,结果显示粗提液中除含有多种组成蛋白质的氨基酸外还有3种未知组分,且含量较高的常见蛋白质氨基酸为丙氨酸、脯氨酸、缬氨酸。采用半制备高效液相色谱系统制备分离了其中一种未知组分的衍生物MWz2,经真空冷冻干燥后为略黄固体粉末,结合核磁共振波谱、高分辨质谱、红外光谱数据,最终鉴定MWz2去掉已知取代基团PITC后的成分为β-丙氨酸,分子式为C3H7nO2,分子量为89.09。Non-protein amino acids were found to have many bioactivities such as anti-cancer,antibacterial,anti-tuberculosis,anti-scurvy and so on.Detection,separation and identification of free amino acids in Sargassum horneri(Turn.) C.Ag.were studied in this paper,which provided technical support for development and utilization of these natural products.Free amino acids were separated by ion-exchange column chromatography from the crude extracts of Sargassum horneri(Turn.) C.Ag.Amino acids were eluted with 3 mol/L NH4OH and the eluate was collected.Many protein amino acids and three unknown components were discovered in Sargassum horneri(Turn.) C.Ag.by PITC-HPLC.The main protein amino acids were alanine,proline,valine.One unknown derivative component(MWZ2) was obtained by preparation HPLC.MWZ2 was slightly yellow solid powder after vacuum freeze-drying.According to analysis of NMR,HR-MS,IR spectroscopy data,the molecular structure of MWZ2 had been elucidated.MWZ2 was β-alanine after removed substituent component of PITC,its molecular formula was C3H7NO2,molecular weight was 89.09.国家海洋局海洋公益项目(200805041

    Construction of genome BAC library for single Branchiostoma belcheri individual

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    隶属于头索动物亚门的文昌鱼是现存生物中最近似于脊椎动物亚门直接祖先的一个类群,具有重要的进化地位,是研究脊椎动物原始祖先的重要材料和模式动物。随着文昌鱼实验室连续繁殖的成功,全基因组测序成为中国文昌鱼模式化急需完成的工作之一。文章从单条雄性白氏文昌鱼精巢组织中提取高质量的基因组dnA,经ECOrⅠ限制性内切酶和ECOrⅠ甲基化酶酶切,脉冲场电泳选择合适酶切dnA片段,连接线性磷酸化的载体PCC1bAC,转化大肠杆菌EPI300 E.COlI,构建了含有44706个克隆的全基因组bAC(bACTErIAl ArTIfICIAl CHrOMOSOME)文库,该文库平均插入片段80kb,具有9倍的基因组覆盖率,基本能够满足功能基因等研究需要,为中国文昌鱼全基因组测序打下基础。As one of the closest living invertebrate relatives of vertebrates,amphioxus(subphylum Cephalochordata) occupies a key position in animal evolution and is becoming the best available proxy and model animal for studying the last common ancestor of all chordates,especially vertebrates.As long-term continuous culturing of amphioxus in laboratory became reliable,for pushing this animal to be a more successful model system,whole-genome sequencing of one or more species derived from this branch will be another urgent issue needed to address.In the present study,we described the construction and characterization of a bacterial artificial chromosome(BAC) library,using a single individual of Chinese amphioxus(Branchiostoma belcheri).High quality genomic DNA extracted from the spermary was partially digested with EcoRⅠand EcoRⅠmethylase.Desirable DNA fragments were isolated by pulsed field gel electrophoresis(PFGE),ligated to linearized and phosphorylased carrier pCC1BAC,and then transformed to Escherichia coli EPI300.The constructed library consists of 44 706 clones with the average insert fragment size around 80 kb as estimated by PFGE.The representation of the library is about 9 equivalents to the amhioxus genome.These results indicate that the BAC library will be useful for functional genomic studies and facilitate the whole-genome sequencing of Chinese amphioxus.国家高技术研究发展计划项目(863计划)(编号:2008AA092602)资

    Preparation of Co-YSZ/HAp Nano-composite Coating on Ti Substrate by Electrochemical Method

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    采用复合电沉积和电泳沉积两步法在钛基体上制备了Co-YSZ/HAp纳米复合涂层,与只采用电泳沉积法在钛基体上制备纳米HAp单一涂层进行了比较研究.采用场发射扫描电镜、X射线衍射和能量散射谱对复合涂层的微观形貌,纳米HAp外层表面形貌,晶相,复合涂层的断面形貌及元素组成分布进行分析研究.通过粘结-拉伸实验测定了涂层与基体的结合强度,结果表明,Co-YSZ/HAp纳米复合涂层与钛基体的结合强度明显高于纳米HAp单一涂层与钛基体的结合强度,说明复合涂层具有更好的力学性能.Co-YSZ/HAp nano-composite coating and nano-HAp single coating were deposited on Ti substrate using the combination of electrocodeposition and electrophoretic deposition, and electrophoretic depositions, respectively. Surface and cross section morphologies of the coatings were observed by scanning electron microscope. Element distribution and crystal phase of the coatings were analyzed by energy dispersive spectrum and X-ray diffraction. The adhesive strength of the coating and Ti substrate was determined by shear strength testing. The results indicate that the adhesive strength of Co-YSZ/HAp nano-composite coating and Ti substrate is higher than that of nano-HAp single coating and Ti substrate. It shows that Co-YSZ as an interlayer reduces the mismatch of the thermal expansion coefficients between HAp and titanium and Co-YSZ/HAp nano-composite coating has better mechanical properties.国家自然科学基金(20573086,200273055);; 福建省自然科学基金(E0210004)资助项

    塔里木沙漠公路防护林生态工程的综合生态环境效应

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    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

    Preparation of Co-YSZ/HAp nano-composite coating on Ti substrate by electrochemical method

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    Co-YSZ/HAp nano-composite coating and nano-HAp single coating were deposited on Ti substrate using the combination of electrocodeposition and electrophoretic deposition, and electrophoretic depositions, respectively. Surface and cross section morphologies of the coatings were observed by scanning electron microscope. Element distribution and crystal phase of the coatings were analyzed by energy dispersive spectrum and X-ray diffraction. The adhesive strength of the coating and Ti substrate was determined by shear strength testing. The results indicate that the adhesive strength of Co-YSZ/HAp nano-composite coating and Ti substrate is higher than that of nano-HAp single coating and Ti substrate. It shows that Co-YSZ as an interlayer reduces the mismatch of the thermal expansion coefficients between HAp and titanium and Co-YSZ/HAp nano-composite coating has better mechanical properties

    中国海及邻近区域碳库与通量综合分析

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    中国海总面积约470万平方公里,纵跨热带、亚热带、温带、北温带等多个气候带.其中,南海北依\"世界第三极\"青藏高原、南邻\"全球气候引擎\"西太平洋暖池,东海拥有全球最宽的陆架之一,跨陆架物质运输显著,黄海是冷暖流交汇区域,渤海则是受人类活动高度影响的内湾浅海.中国海内有长江、黄河、珠江等大河输入,外邻全球两大西边界流之一的黑潮.这些鲜明的特色赋予了中国海碳储库和通量研究的典型代表意义.文章从不同海区(渤海、黄海、东海、南海)、不同界面(陆-海、海-气、水柱-沉积物、边缘海-大洋等),以及不同生态系统(红树林、盐沼湿地、海草床、海藻养殖、珊瑚礁、水柱生态系统等)多层面对海洋碳库与通量进行了较系统地综合分析,初步估算了各个碳库的储量与不同碳库间的通量.就海气通量而言,渤海向大气中释放CO2约0.22Tg Ca-1,黄海吸收CO2约1.15Tg Ca-1,东海吸收CO2约6.92~23.30Tg Ca-1,南海释放CO2约13.86~33.60Tg Ca-1.如果仅考虑海-气界面的CO2交换,中国海总体上是大气CO2的\"源\",净释放量约6.01~9.33Tg Ca-1.这主要是由于河流输入以及邻近大洋输入所致.河流输入渤黄海、东海、南海的溶解无机碳(DIC)分别为5.04、14.60和40.14Tg Ca-1,而邻近大洋输入DIC更是高达144.81Tg Ca-1,远超中国海向大气释放的碳量.渤海、黄海、东海、南海的沉积有机碳通量分别为2.00、3.60、7.40、7.49Tg Ca-1.东海和南海向邻近大洋输送有机碳通量分别为15.25~36.70和43.39Tg Ca-1.就生态系统而言,中国沿海红树林、盐沼湿地、海草床有机碳埋藏通量为0.36Tg Ca-1,海草床溶解有机碳(DOC)输出通量为0.59Tg Ca-1;中国近海海藻养殖移出碳通量0.68Tg Ca-1,沉积和DOC释放通量分别为0.14和0.82Tg Ca-1.总计,中国海有机碳年输出通量为81.72~103.17Tg Ca-1.中国海的有机碳输出以DOC形式为主,东海向邻近大洋输出的DOC通量约15.00~35.00Tg Ca-1,南海输出约31.39Tg Ca-1.综上,尽管从海-气通量看中国海是大气CO2的\"源\",但考虑了河流、大洋输入、沉积输出以及微型生物碳泵(DOC转化输出)作用后,中国海是重要的储碳区.需要指出的是,文章数据是基于中国海各海区碳循环研究报道,鉴于不同研究方法上的差异,所得数据难免有一定的误差范围,亟待将来统一方法标准下的更多深入研究和分析.国家重点研发计划项目(编号:2016YFA0601400);;国家自然科学基金项目(批准号:91751207、91428308、41722603、41606153、41422603);;中央高校基础研究项目(编号:20720170107);;中海油项目(编号:CNOOC-KJ125FZDXM00TJ001-2014、CNOOCKJ125FZDXM00ZJ001-2014)资

    中国物理海洋学研究70年:发展历程、学术成就概览

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    本文概略评述新中国成立70年来物理海洋学各分支研究领域的发展历程和若干学术成就。中国物理海洋学研究起步于海浪、潮汐、近海环流与水团,以及以风暴潮为主的海洋气象灾害的研究。随着国力的增强,研究领域不断拓展,涌现了大量具有广泛影响力的研究成果,其中包括:提出了被国际广泛采用的"普遍风浪谱"和"涌浪谱",发展了第三代海浪数值模式;提出了"准调和分析方法"和"潮汐潮流永久预报"等潮汐潮流的分析和预报方法;发现并命名了"棉兰老潜流",揭示了东海黑潮的多核结构及其多尺度变异机理等,系统描述了太平洋西边界流系;提出了印度尼西亚贯穿流的南海分支(或称南海贯穿流);不断完善了中国近海陆架环流系统,在南海环流、黑潮及其分支、台湾暖流、闽浙沿岸流、黄海冷水团环流、黄海暖流、渤海环流,以及陆架波方面均取得了深刻的认识;从大气桥和海洋桥两个方面对太平洋–印度洋–大西洋洋际相互作用进行了系统的总结;发展了浅海水团的研究方法,基本摸清了中国近海水团的分布和消长特征与机制,在大洋和极地水团分布及运动研究方面也做出了重要贡献;阐明了南海中尺度涡的宏观特征和生成机制,揭示了中尺度涡的三维结构,定量评估了其全球物质与能量输运能力;基本摸清了中国近海海洋锋的空间分布和季节变化特征,提出了地形、正压不稳定和斜压不稳定等锋面动力学机制;构建了"南海内波潜标观测网",实现了对内波生成–演变–消亡全过程机理的系统认识;发展了湍流的剪切不稳定理论,提出了海流"边缘不稳定"的概念,开发了海洋湍流模式,提出了湍流混合参数化的新方法等;在海洋内部混合机制和能量来源方面取得了新的认识,并阐述了混合对海洋深层环流、营养物质输运等过程的影响;研发了全球浪–潮–流耦合模式,推出一系列海洋与气候模式;发展了可同化主要海洋观测数据的海洋数据同化系统和用于ENSO预报的耦合同化系统;建立了达到国际水准的非地转(水槽/水池)和地转(旋转平台)物理模型实验平台;发展了ENSO预报的误差分析方法,建立了海洋和气候系统年代际变化的理论体系,揭示了中深层海洋对全球气候变化的响应;初步建成了中国近海海洋观测网;持续开展南北极调查研究;建立了台风、风暴潮、巨浪和海啸的业务化预报系统,为中国气象减灾提供保障;突破了国外的海洋技术封锁,研发了万米水深的深水水听器和海洋光学特性系列测量仪器;建立了溢油、危险化学品漂移扩散等预测模型,为伴随海洋资源开发所带来的风险事故的应急处理和预警预报提供科学支撑。文中引用的大量学术成果文献(每位第一作者优选不超过3篇)显示,经过70年的发展,中国物理海洋学研究培养了一支实力雄厚的科研队伍,这是最宝贵的成果。这支队伍必将成为中国物理海洋学研究攀登新高峰的主力军

    Y型聚乙二醇干扰素琢-2b注射液治疗HCV基因2/3型慢性丙型肝炎患者疗效和安全性的多中心随机对照试验研究

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    目的以标准剂量的聚乙二醇干扰素(Peg IFN)α-2a联合利巴韦林作为阳性对照,评价新型试验药物Y型Peg IFNα-2b注射液联合利巴韦林治疗2型/3型慢性丙型肝炎(CHC)患者的疗效和安全性。方法采用多中心、随机开放、阳性药对照的Ⅲ期临床试验,筛选符合要求的2型/3型CHC患者,按照2:1的比例随机分配到Y型Peg IFNα-2b组和Peg IFNα-2a组,同时口服利巴韦林,疗程24 w,停药随访24 w。采用Abbott Real Time HCV Genotype II检测HCV基因型,采用Cobas Taq Man实时定量PCR法检测血清HCV RNA水平。详细记录不良事件。主要疗效指标为持续病毒学应答(SVR),并进行非劣效检验。结果本试验实际入组2型/3型CHC患者255例,实际治疗241例。全分析集(FAS)数据显示,158例试验组和83例对照组患者SVR分别为85.4%(95%CI 79.94%~90.94%)和79.5%(95%CI 70.84%~88.20%,P=0.2402);对符合方案分析集(PPS)人群分析显示,试验组和对照组患者SVR分别为87.9%(95%CI 82.45%~93.27%)和85.9%(95%CI 77.82%~94.01%,P=0.7060),率差的95%可置信区间均符合非劣效标准;对PPS人群分析显示,85.8%受试者获得了早期病毒学应答(RVR),RVR的阳性预测值为90.1%;试验组和对照组不良事件发生率相似,分别为95.6%和95.2%,严重不良事件发生率分别为3.8%和3.6%。结论应用Peg IFNα联合利巴韦林治疗2型/3型CHC患者,新型试验药物Y型Peg IFNα-2b具有与对照药物Peg IFNα-2a相似的疗效和安全性。国家科技部“十二五”重大专项(编号:2012ZX10002-003);“重大新药创制”十二五科技重大专项(编号:2012ZX09303019)

    Design and Test of Solar-Heat Pump Drying System

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    An exemplary platform of solar-heat pump drying system was established so as to promote its application in drying industry. Constant temperature operation in drying process is achieved by the au- tomatic control system, and waste heat is reclaimed by hea
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