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人下颌恒切牙管间峡区解剖的显微CT研究  [PDF]
刘成霞,李文,郑庆华,耿宁,孙拓祺,黄定明
华西口腔医学杂志 , 2010, DOI: 10.3969/j.issn.1000-1182.2010.02.016
Abstract: 目的研究人离体下颌恒切牙管间峡区的解剖学特点。方法选择离体下颌恒切牙拍摄近远中向X线片,选出双根管牙33颗,对距根尖6mm以内的牙根组织进行显微CT扫描。扫描层厚20μm,每颗牙齿获得扫描截面300个。通过三维重建观察牙根管间峡区的解剖形态。记录距根尖1、2、3、4、5、6mm处各截面根管数目及管间峡区的出现情况,并测量根管壁的最小厚度。结果所有双根管下颌恒切牙都存在管间峡区,完全峡区占49.7%,部分峡区占4.5%。距根尖6mm内各截面管间峡区的出现率为10.0%~85.5%,卡方检验显示距根尖1~6mm处管间峡区出现率的差异有统计学意义(P=0.001)。距根尖3~6mm处管间峡区出现率较高,以5mm处最高,为85.5%。距根尖6mm以内的根管壁最小厚度均小于0.5mm。结论下颌恒切牙管间峡区的出现率较高,根管壁最小厚度位于峡部,在临床进行根管治疗和牙髓外科手术时应引起重视。
扫描电镜评价mtad对根尖区管间峡部感染物的清除效果  [PDF]
包旭东,姚娜,郭惠杰,张成飞,岳林
北京大学学报(医学版) , 2012,
Abstract: ?目的:评价mtad根管冲洗剂清除根尖区峡部感染物的效果。方法:收集有管间峡部结构的上颌第一前磨牙15颗,建立粪肠球菌感染根管模型,分为5组,每组3颗。第1组不做根管预备,作为粪肠球菌感染状态的基线对照,其余4组采用protaper旋转镍钛锉进行根管机械预备,冲洗分别用生理盐水、mtad、次氯酸钠和次氯酸钠+edta。根管预备后制备扫描电镜标本,观察管间峡部表面细菌群落和玷污层的状态。结果:生理盐水组峡部表面厚层玷污层中嵌有大量细菌,玷污层评分中位数为5;mtad组峡部表面也铺有玷污层,但玷污层评分较小,中位数为3,嵌入其中的细菌有破壁现象;次氯酸钠组峡部表面铺满牙本质泥,中位数也为5,但不含细菌;次氯酸钠+edta组峡部表面干净,牙本质小管和管间结构清晰,玷污层评分的中位数最小为1。结论:mtad可渗入根尖区管间峡部,部分去除玷污层,但杀菌效果较弱;次氯酸钠配合edta冲洗可有效清除管间峡部的感染。
九甸峡水利枢纽坝区地下水低凹带成因研究  [PDF]
钱海涛,司富安,马平,李广诚
人民黄河 , 2006,
Abstract: ?针对九甸峡水利枢纽坝区近河流两岸存在地下水低凹带这一少见的现象,从坝址所处的地质环境出发,对可能影响坝区地下水流场的主要因素进行了综合分析.认为坝区不存在地下水渗流的集中通道,裂隙发育规律对地下水流场具有控制性作用,并且两岸岩体渗透性在垂向分层具有不对称的"v"形和"w"形特征,这两种因素共同作用导致了地下水在近河流两岸形成低凹带并具有差异性.数值模拟进一步表明了此结论的正确性.
金沙峡电站闸坝区渗流场有限体积法数值模拟  [PDF]
杨海英,陈刚,柴军瑞,张志昌
岩土力学 , 2005,
Abstract: 为实现泄冲闸、进水闸和土坝结合部位三维渗流场真实区域的数值模拟,采用有限体积法对含排水孔在内的闸坝区三维渗流场进行了网格划分。根据计算结果可知,闸基处防渗墙效果微弱,溢出点垂直坡降大于允许值,对工程不利,并提出了相应的改进措施。
台湾海峡及邻区剖面岩石圈有效弹性厚度及其构造意义
Lithosphere Effective Elastic Thickness and Its Tectonic Implications in Taiwan Strait and Its Adjacent Regions
 [PDF]

王明明,吴健生
Wang Mingming
, Wu Jiansheng

地球科学(中国地质大学学报) , 2017, DOI: 10.3799/dqkx.2017.524
Abstract: 台湾海峡及邻区地处欧亚板块与菲律宾海板块相互作用的构造前锋部位,经历了挤压、剪切和伸展交替或并重的构造作用,这种复杂应力环境下岩石圈的均衡调整对台湾地区的构造演化具有深远影响.通过采用均衡响应函数法计算穿越台湾海峡及邻区剖面岩石圈的有效弹性厚度,利用剥离法消除台湾海峡及东邻岛区较厚沉积层的影响,得到了穿越台湾海峡地区剖面岩石圈弹性厚度的变化.结合反演的莫霍面和居里面深度对剖面有效弹性厚度的构造意义进行了综合分析.结果表明:台湾海峡及邻区岩石圈有效弹性厚度变化范围为22~8km,剖面有效弹性厚度整体上自西往东呈楔形递减趋势,反映中国东部大陆岩石圈往东伸展减薄;台湾岛附近有效弹性厚度出现局部向东倾斜增大的趋势,可能与东侧菲律宾海板块的仰冲挤压有关.有效弹性厚度与居里面具有较高相关性,反映了有效弹性厚度受岩石圈热结构的影响.
Taiwan Strait and its adjacent regions are located in the tectonic interaction front of Eurasia plate and Philippine Sea plate, they have alternately or jointly undergone extrusion, shearing and stretching tectonic processes. The isostatic adjustment has a profound effect on the tectonic evolution of Taiwan region under the complex stress environment. In this paper, we calculated the lithosphere effective elastic thickness (Te) of Taiwan Strait and its adjacent regions by isostatic response function method, and eliminated the sediment effect by stripping method, then we attained the effective thickness changes along the profile across Taiwan Strait. The effective thickness changes and its tectonic significance were analyzed, combining inversion results of Moho depth and Curie depth. The results show that the lithosphere effective elastic thickness of Taiwan Strait and its adjacent regions range from 22 to 8km. The continental lithosphere in eastern China shows thinning trend eastward by decreasing effective elastic thickness from west to east. The effective elastic thickness increasing eastward under Taiwan Island is likely to be associated with obduction extrusion of Philippine plate. A high correlation between effective elastic thickness and Curie depth reflects Te is controlled by lithosphere temperature structure
中天山东段星星峡群变质泥质岩的地球化学特征及其对物源区和古风化作用的制约  [PDF]
李秋根,刘树文,韩宝福,王月然,党青宁
中国科学 地球科学 中国科学 地球科学 , 2005,
Abstract: ?中天山东段中元古代星星峡群变质泥质岩的常量元素、微量元素和稀土元素特征表明,它们的Sr,Hf和Zr比后太古代页岩相对富集,其他元素与NASC和PAAS特征相似.星星峡群变质泥质岩Al2O3/TiO2,Cr/Zr,Cr/Th和Th/Sc的比值和高Zr含量等表明源区物质以长英质岩石为主,同时有少量铁镁质岩石的加入.REE配分模式表现轻、重稀土高度分馏特征,(La/Yb)n的均值为18.6.一些样品表现较小的负Eu异常(Eu/Eu*=0.7~0.84),表明物源中有不成熟的年轻弧物质的加入.星星峡群变质泥质岩样品具有低的K2O/Al2O3的比值,表明源区物质中的碱性长石含量较低,物源中斜长石和钾长石的比值为5:1,在成分上相当于英云闪长岩和花岗闪长岩.低CIA值和高ICV值特征指示星星峡群变质泥质岩的物源区古风化程度较低,沉积物的成分成熟度低.地球化学特征也表明样品沉积在大陆岛弧体系下的弧后盆地构造背景.
基于层区带刻度区地质特点的资源评价方法适用性分析  [PDF]
,张雪峰,罗安湘,惠潇,赵彦德,王克,黄锦绣
- , 2016,
Abstract: 针对新型的层区带刻度区进行资源评价方法的适应性研究是长庆四次资评一项重要内容。采用油藏规模序列法、油藏过程模型法、容积法和饱和探井法4种资源评价方法,对具不同成藏特点的刻度区进行了深入的方法适用性分析和参数研究。研究结果表明,过程类资源评价方法对低渗透、特低渗透连续性岩性油藏,在以储量提交单元作为统计单元进行油藏发现序列与规模序列模拟时,计算参数的合理性与计算结果认知度很难达到统一。而勘探程度类资源评价方法,在深入的地质分析基础上,选择合理适宜的关键参数,是可以求得较为可信的地质资源量。当然,评价者对评价对象的认识程度和对评价方法的掌握程度也影响着资源评价的结果。
Response of phytoplankton to nutrients addition in the upwelling regions of the Taiwan Strait
台湾海峡上升流区浮游植物对营养盐添加的响应

WANG Yu-Jue,HONG Hua-Sheng,WANG Da-Zhi,HUANG Bang-Qin,ZHANG Fan,
王玉珏
,洪华生,王大志,黄邦钦,张钒

生态学报 , 2008,
Abstract: In situ incubation experiments of nutrients addition to surface water from the upwelling region in the Taiwan Strait were conducted to investigate nutrient limitation of this area and the main factors that caused the phytoplankton bloom in June, 2006. Variation of nutrients, Chl-a concentration and phytoplankton species density were analyzed. The results showed no clear limitation by silicon, however clear nitrogen and phosphate limitations were found, and nitrogen limitation was more serious than phosphate limitation. Diatoms, such as Asterionellopsis glacialis grew immediately to become the dominant species after nutrients were added. Different mechanisms were used to explain the assimilation of nitrogen and phosphate by these dominant diatoms. Nitrogen was taken up and assimillated immediately after it was added. Ammonium addition resulted in rapid growth and die-out of the dominant diatoms compared with that of nitrate addition. However, because of the phosphate pool inside phytoplankton, the added phosphate was taken up quickly and stored, then assimilated slowly. The results suggest that nitrogen supply was the main factor that caused the phytoplankton bloom in the Taiwan Strait during the upwelling in 2006.
Reading the Planetary Archipelago of the Torres Strait  [PDF]
Elizabeth McMahon
Island Studies Journal , 2013,
Abstract: This essay makes use of the Western concept of the archipelago as a starting point for an examination of island to island relations in the Torres Strait, Australia, as they are rehearsed in the imaginary domain of story, in both its written and oral modes. The essay deploys Spivak’s notions of planetarity and Bloch’s concept of utopianism as ways of charting the relationship between two Torres Strait stories, one old, one new. In so doing, the essay seeks to identify the capacity of Torres Strait literature and storytelling to re-conceive relations of space and time and to acknowledge a spatial and temporal mobility running parallel to the circumscribed trajectories of late modernity.
RECENT FORAMINIFERAL COMMUNITIES IN MAKASSAR STRAIT  [cached]
Ricky Rositasari
Journal of Coastal Development , 2010,
Abstract: Makassar strait is the very unique waters, the bottom topography was steep and complex, the waters masswas also exceptional since Indonesian through flow carried flavor water from Pacific warm pool to the area.To describe the exceptional of Makassar Strait hydrological characteristics through recent foraminiferalcommunity structure as a proxy, Oceanographical Expedition in Makassar Strait was conducted in October2004. Research Vessel of Baruna Jaya VII was used to carry out the research activities. Sediment layers arean essential tool on recording hydrological information in such period of time, and each certain layerpreserved certain information as a bench mark data at a time period. The result shows that there are 5genera of planktonic foraminifera which generated a bulk in sediment surface. Deep chlorophyll maximum inoceanic region of Makassar Strait was prominent factor generated living planktonic foraminifera in researchlocation. Benthic community was formed by 164 species from 78 genera. Water depth was affected to benthicforaminiferal diversity, distribution and species diversity, which reveal that water depth was limiting factorto benthic foraminiferal assemblage. Uvigerinid was the important taxa which make up 46 to 57 % of thebenthic specimen, particularly in river input yield adjacent area. Uvigerina asperula may considered as anindicator of OMZ (Oxygen minimum zone) in Makassar Strait.
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