111 research outputs found

    电离空气环境中碳化材料的烧蚀

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    本文给出了电离空气环境中碳化材料热化学烧蚀参数的计算方法。由于采用了比较精确的传递系数关联公式和改进了烧蚀表面气体成分的计算方法,因而可以用相当简单的方法得到与耦合(化学反应边界层与烧蚀表面耦合)计算非常符合的结果。本文方法可以得到碳化材料烧蚀表面气体的电离特性;为烧蚀电离边界层计算提供壁面边界条件。也可以用来进行热防护设计

    3种养殖方式下沐浴角骨海绵生长状况的差异分析

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    沐浴角骨海绵(Spongia officinalis)主要分布于海南沿海,其骨架不由骨针而是由海绵硬蛋白组成,因而拥有良好的吸水性和柔性,在海洋生物材料开发领域具有较好前景。为了培育该地域特色的海绵品种,在海南省儋州水牛坡村潮间带海域(109.40° E, 19.87° N)开展了为期一年半的沐浴角骨海绵人工养殖,通过组织块的长、宽、高变化表征海绵的增长,分析了3种养殖方式下该海绵的生长状况差异。结果显示:在瓷砖法、穿绳法和弹簧法养殖方式下的角骨海绵均有较高的存活率,分别为80%,60%和50%,其中以瓷砖法最佳。在瓷砖法下,海绵组织块的平均长度增长率为67.1%,显著高于穿绳法和弹簧法(p<0.05),平均宽度增长率为63.5%,平均高度增长率为73.2%,可见瓷砖法相对于其他两种方式在存活率和增长率有较大优势,适宜于沐浴角骨海绵的养殖。此外,生长指标与海水温度的相关性分析结果表明,沐浴角骨海绵组织块的增长与水温之间的相关性不显著,增长速度不呈季节性变化。综上,在自然条件下获得的沐浴角骨海绵的第一手养殖资料有助于基础的海绵生物学研究,促进未来当地特色海洋经济的发展。海南省本级部门预算项目厦门南方海洋研究中心项目(17GYY008NF04

    肉桂酸对人骨肉瘤MG-63细胞增殖和分化的影响

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    目的研究中药有效成分肉桂酸对人骨肉瘤MG-63细胞增殖和分化的影响。方法肉桂酸处理MG-63细胞前后,台盼蓝拒染法进行活细胞计数;流式细胞仪检测细胞周期时相变化;光镜和电镜观察细胞形态和超微结构;VanGieson染色检测细胞Ⅰ型胶原表达;茜素红染色观察钙化骨结节形成;免疫细胞化学检测骨粘素和骨钙蛋白表达。结果肉桂酸明显抑制MG-63细胞增殖,D7抑制率达54.94%±4.69%。周期分析结果显示,肉桂酸处理后G0/G1期细胞比例较对照组明显升高(P<0.01)。光镜和电镜结果显示,肉桂酸处理组MG-63细胞形态和超微结构发生明显改变,呈现相应正常细胞的形态和超微结构特征。肉桂酸促进成骨细胞分化标志物Ⅰ型胶原、骨粘素和骨钙蛋白的表达与钙沉积以及典型骨结节的形成。结论肉桂酸可抑制人骨肉瘤MG-63细胞增殖并诱导其向成骨细胞分化

    HYDROLOGICAL OBSERVATION IN AN EVERGREEN BROAD LEAVED FOREST IN THE WUYI MOUNTAINS

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    [中文文摘]对武夷山甜槠林成熟林水文学效应的研究结果表明:观测期间,年大气降水量2678.78mm,林内雨量2182.04mm,林冠截留量为496.74mm;林内雨中,穿透雨量2082.08mm,树干茎流99.96mm;到达甜槠林地作用面的林内雨量中,被地表枯枝落叶层截留的雨量为159.84mm,地表径流量11.6mm,地下渗流量109.32mm,其余林内雨量形成土壤含水量增量并由地表物理蒸发、根系吸收以及植物蒸腾所消耗;甜槠林地o~200cm土层水分初渗率78.6mm·min-1,稳渗率15.5mm·min-1,达到稳渗历时45min,地表枯枝落叶最大持水量5.2mm,土壤蓄水量154.0mm。与国内其它地区不同类型的森林相比较,武夷山甜槠林具有较强的水文学效能。[英文文摘]Hydrological observations were made in a 76 year old Castanopsis eyrei forest of the Wuyi Mountains.The results are as follows:(1)In the study period during 1993~1994,annual gross precipitation,net precipitation (throughfall was 208204mm and stemflow was 9996mm)and interception loss were 267878mm,218204mm and 49674mm respectively.Interception rate was 1845%.(2)Net precipitation,the part of gross precipitation appearing on the forest floor,was redistributed through different routes.The part absorbed by litter layer was an annual amount of 15984mm,and accounting for 733%.The parts as surface runoff and below ground drainage were annual amounts of 116mm and 10932mm respectively,and accounting for0.53% and 5.01%,respectively.The rest was kept in soil and then lost to the atmosphere by means of ground physical evaporation or plant transpiration as absorbed by the roots.Its amount was 190128mm,and accounting for 87.13%.(3) The initial infiltration rate and stable infiltration rate for the soil layer of 0~20cm were 786mm·min-1 and 155mm·min-1 respectively.The time needed to arrive at the stable state was 45min.Water storage capacity of soil was 15041t·hm-2.The maximum water holding capacity of litter layer was 52mm.福建省自然科学基金,武夷山自然保护区管理局资

    第十八届美国理论与应用力学大会总结

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    1会议概况2018年6月5—9日,第18届美国理论与应用力学大会(18th U.S. National Congress of Theoretical and Applied Mechanics, USNCTAM2018)在美国芝加哥召开.本次大会由美国力学国家委员会和中国力学学会联合主办,旨在探讨和交流近四年世界范围内在理论和应用力学领域的基础研究、创新技术的最新进展,吸引了来自世界各地的近千名专家学

    Effect of relieving fever and reducing plasmas glucose of 3 kinds of Digupi on albino rats

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    作者简介: 黄小红(1966- ) , 女, 讲师, 硕士. 研究方向: 动物生物化学.用 3种地骨皮 (枸杞根皮、宁夏枸杞根皮、北方枸杞根皮 )原生药总提取物灌喂大、小白鼠 ,测定它们对白鼠的解热和降血糖作用 .结果表明 :枸杞根皮和宁夏枸杞根皮对角叉菜胶致热的大白鼠有明显的解热作用 ;北方枸杞虽也有明显解热作用 ,但其作用强度弱于枸杞和宁夏枸杞 .3种枸杞根皮中仅枸杞根皮对四氧嘧啶小白鼠有明显降血糖作用 ,其余 2种地骨皮降血糖作用不甚明显

    AFLP analysis of arbuscular mycorrhizal fungi in roots of Prunus mume

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    第一作者: 蔡邦平,博士,副研究员。主要研究方向: 园林植物与观赏园艺、植物菌根。电话: 0592--2039576 Email : cbangping@ 163.com 地址: 361003 福建省厦门市思明区虎园路25 号厦门市园林植物园。[中文文摘]为了解决梅根系共生的丛枝菌根(AM)真菌难以应用形态学鉴定的问题,以巢式PCR的AFLP方法研究梅根系AM真菌DNA多态性。试验采集梅花期的根系样品,应用改良CTAB法提取总DNA,经纯化处理后,应用巢式PCR扩增根系AM真菌基因片段,进行AFLP分析。结果表明,18个梅品种的30个根系样品中,仅有8个样品经巢式PCR后获得纯化的DNA片段,占试验样品数的26.7%;8个样品共得到指纹图谱带24条,各样品平均多态性位点数为3.0个,Nei’s基因多样性为0.4097±0.0848,Shannon信息指数为0.5968±0.0955;利用Nei’s遗传相似性系数聚类,梅品种根系内AMF基因组DNA的聚类类别与梅"品种群"这一分类级别无相关性。该试验为植物根系共生AM真菌DNA多态性研究提供了一种简便的技术。[英文文摘]DNA polymorphism of arbuscular mycorrhizal fungi (AMF) was analyzed through the method of DNA amplification by nested PCR based on AFLP marker,in order to solve the difficulty of identifying the species of AMF associated with mei flowers (Prunus mume Sieb.et Zucc.).A total of 30 root samples from 18 mei cultivars were collected in the flowering phase from Wuhan Mei Garden as experimental materials.The results show that the purified DNA can be extracted only from eight root samples that account for 26.7% of total root samples.Totally 24 polymorphic loci were obtained from eight sample roots,averaging 3. 0 loci for each sample.The average genetic identity was 0. 409 7 ±0. 084 8,and the Shannon information index was 0. 596 8 ± 0. 095 5. The clustered groups of AMF DNA by AFLP marker from different cultivars were not identical with cultivar groups of P.mume.The results indicate that the AFLP marker technology is a brief and effective method to study the DNA polymorphism for the AMF in the roots of a plant.教育部科学技术研究重点项目(104034);; 国家自然科学基金项目(30670047);; 厦门市科技计划项目(3502Z20072010、3502Z20112004

    Damage to mangroves from extreme cold in early 2008 in southern China

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    通讯作者Author for correspondence (E-mail: [email protected])2008年初,我国南方19个省经历了50年一遇的持续低温雨雪冰冻天气。极端气候对华南沿海各省的红树林区造成不同程度的危害。2008年3月,在我国南方各省红树林区的10个代表性地点,对这次寒害造成的红树植物伤害程度进行了系统的调查。结果表明:冬季低温对红树林的影响极为显著,特别是在低纬度的海南、广西和广东湛江,由于极端低温正值夜间退潮,对红树林的影响更为显著;在纬度较高的福建,本地红树种类秋茄(Kandelia obovata)、桐花树(Aegiceras corniculatum)和白骨壤(Avicennia marina)及引种的木榄(Bruguiera gymnorrhiza)等,由于长期适应于冬季较低的气温或在种植前经过抗寒锻炼,具有较强的抗寒能力。各地主要红树植物中,广布种秋茄、桐花树和白骨壤最为耐寒,其耐寒性均大于红树科的木榄、海莲(Bruguiera sexangula)和红海榄(Rhizophora stylosa)。海桑(Sonneratia caseolaris)对温度的敏感性最强,抗寒能力最低,因此,即使在其原产地海南也受到较为严重的寒害,在纬度更高的引种地出现大面积受害甚至全部死亡,而从孟加拉国引种的无瓣海桑(Sonneratia apetala)却显示出一定的抗寒能力。同一地点的红树植物幼苗的抗寒能力低于大树。此次寒害也造成了苗圃场的种苗大量死亡,成熟的植株提前落花落果,这势必会影响后继一两年内红树林的自然更新和人工造林。因此,在未来红树林造林或人工引种中,一定要考虑到红树植物的抗寒能力。国家自然科学基金(30671646和30700092);厦门大学“闽江学者”启动基

    Cbfa1/Runx2 and regulation of osteoblast differentiation

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    成骨细胞是由间充质干细胞经骨原细胞和前成骨细胞分化而来的。近年来已鉴定转录因子Cbfa1(core binding factor a1)是成骨细胞分化和骨形成的关键调控因子。在成骨细胞分化的过程中,Cbfa1通过调控成骨细胞特异性细胞外基质蛋白基因的表达和成骨细胞周期参与成骨细胞的分化过程。新近发现Cbfa1能通过自身的PST序列区域与Smads结合形成复合物共同参与成骨细胞的分化调控。Osteoblasts differentiate originally from mesenchymal stem cells through two progressive develop-mental steps: osteoprogenitors and pre-osteoblasts. In recent years,Cbfa1(core binding factor a1) has beenidentified as a key regulator of osteoblast differentiation and bone formation. During osteoblast differentiation,Cbfa1 is involved in this differentiation course by regulating expression of osteoblast-specific extracellular matrixproteins and osteoblastic cell cycle. It has recently been found that Cbfa1 can interact and form complexesthrough its PST domain with Smads to regulate osteoblast differentiation cooperatively.国家自然科学基金资助项目(30170724
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