水平离散网格与大气运动   总被引：8，自引：0，他引：8  

LIU Yudi  WANG Bin  JI Zhongzhen 《大气科学进展》2003,20(1):139-148

从线性浅水方程组出发,在Arakawa A-E网格和z网格上,从频率和群速方面讨论了这六种网格对大气中的两种重要的波动：惯性重力波和Rossby波的描述能力。结果表明：C、z、E网格比其它网格产生的歪曲都要小。  相似文献   

Age model, physical properties and paleoceanographic implications of the middle Pleistocene core sediments in the Choshi area, central Japan     

Koji  Kameo  Makoto  Okada  Moamen  El-Masry  Toshio  Hisamitsu  Saneatsu  Saito  Hiroomi  Nakazato  Naohiko  Ohkouchi  Minoru  Ikehara  Hisato  Yasuda  Hiroshi  Kitazato  Asahiko  Taira 《Island Arc》2006,15(3):366-377

Abstract   A continuous, well-preserved core was obtained from the Choshi area, on the Pacific side of Japan, to investigate paleoceanographic and paleoclimatic changes around the northwestern Pacific region during the middle Pleistocene. Siliciclastic sequences in the core are divided into five formations – the Obama, Yokone, Kurahashi and Toyosato Formations in the Inubo Group and the Katori Formation, in ascending order. Examination of calcareous nannofossils and magnetic polarities detected four datums in the core sediments of the Inubo Group: the top of Reticulofenestra asanoi , the base of Helicosphaera inversa , the top of Pseudoemiliania lacunosa and the Brunhes–Matuyama boundary. Fourteen marine isotope stages (MIS24–MIS11) were identified in the δ¹⁸O and δ¹³C records based on detected datums and the graphic correlation with the standard stack oxygen isotope curve. Magnetic susceptibility and gamma-ray attenuation porosity evaluator density were also measured and low values characterize the glacial intervals. Biogenic sedimentation by primary production may be larger during the glacial periods because of invasions of nutrient-rich northern surface-waters related to the southward shift of the Kuroshio front in the Choshi area.  相似文献   

铜改性坡缕石的结构特征与抗菌性能研究   总被引：4，自引：0，他引：4  

赵娣芳  周杰  楼必君  刘宁  陈杰 《矿物学报》2006,26(2):219-223

采用液相离子交换法制备了铜改性坡缕石,通过正交实验得到的最佳改性工艺条件为:母液初始浓度为0.02 mol/L,反应温度95℃,常压,反应时间6 h。所制备的Cu2 改性坡缕石对大肠杆菌、金黄色葡萄球菌48 h抑菌率分别达到了87.3%和82.2%。对铜改性坡缕石的晶体结构特征和微观形貌的测定和分析结果表明,铜改性坡缕石仍然保持着坡缕石的基本晶体结构,但结晶度有所降低,晶体颗粒更易分散,单晶表面略显粗糙,单晶的长度有所变小。  相似文献   

高密度聚乙烯/纳米辉钼矿复合材料性能研究     

吴伟端  周丽春  郭胜平  牛牧童  肖凤英  赵煌 《矿物学报》2006,26(3):281-284

以径厚为30~45 nm的辉钼矿作为导电填料,采用熔融共混法制备高密度聚乙烯/纳米辉钼矿复合材料,应用高阻计ZC-36、SEM、XRD、TG等研究复合材料的电性能、晶体结构、界面微观形貌、热性能等。研究结果表明:当纳米辉钼矿含量为25%,复合材料的体积电阻率为5.1×109Ωcm,纳米辉钼矿高定向排列,呈链状集合体;复合材料tonset分解温度提高了35℃;辉钼矿的晶体结构发生变化,(002)晶面2θ右移了1.12°,面间距缩小0.257 nm。  相似文献   

公路路产管理系统的设计与开发     

邹璇  田福娟  张勇  王振辉 《测绘信息与工程》2006,31(1):50-51

采用了Visual C 以及Access技术,实现了模块化的公路路产管理系统,阐明了系统各模块的功能及其相互关系。  相似文献   

Properties and Stability of a Meso-Scale Line-Form Disturbance   总被引：1，自引：0，他引：1  

沈新勇  丁一汇  赵南 《大气科学进展》2006,23(2):282-290

By using the 3D dynamic equations for small- and meso-scale disturbances, an investigation is performed on the heterotropic instability (including symmetric instability and traversal-type instability) of a zonal line-like disturbance moving at any angle with respect to basic flow, arriving at the following results: (1) with linear shear available, the heterotropic instability of the disturbance will occur only when flow shearing happens in the direction of the line-like disturbance movement or in the direction perpendicular to the disturbance movement, with the heterotropic instability showing the instability of the internal inertial gravity wave; (2) in the presence of second-order non-linear shear, the disturbance of the heterotropic instability includes internal inertial gravity and vortex Rossby waves. For the zonal line-form disturbance under study, the vortex Rossby wave has its source in the second-order shear of meridional basic wind speed in the flow and propagates unidirectionally with respect to the meridional basic flow. As a mesoscale heterotropic instable disturbance, the vortex Rossby wave has its origin from the second shear of the flow in the direction perpendicular to the line-form disturbance and is independent of the condition in the direction parallel to the flow; (3) for general zonal line-like disturbances, if the second-order shear happens in the meridional wind speed, i.e., the second shear of the flow in the direction perpendicular to the line-form disturbance, then the heterotropic instability of the disturbance is likely to be the instability of a mixed Rossby–internal inertial gravity wave; (4) the symmetric instability is actually the instability of the internal inertial gravity wave. The second-order shear in the flow represents an instable factor for a symmetric-type disturbance; (5) the instability of a traversal-type disturbance is the instability of the internal inertial gravity wave when the basic flow is constant or only linearly sheared. With a second or nonlinear vertical shear of the basic flow taken into account, the instability of a traversal-type disturbance may be the instability of a mixed vortex Rossby – gravity wave.  相似文献   

鲁西大井头地区隐爆角砾岩特征及其金成矿性研究          下载免费PDF全文

王照波  刘金民  臧学农  刘巨龙 《地质找矿论丛》2006,21(3):168-172

大井头地区隐爆角砾岩主要分布在大井头、归后庄和埠西桥等地,隐爆角砾岩与中生代形成的铜石杂岩体具有成因关系.结合化学分析、微量元素、激电中梯测量资料,分析了该区隐爆角砾岩的金成矿性,确定了归后庄、埠西桥为不成矿隐爆角砾岩,查明大井头隐爆角砾岩具有较好的成矿前景,并通过激电中梯测量圈定了一个极具成矿前景的靶区.  相似文献   

塔中地区石炭系东河砂岩储层物性影响因素研究   总被引：4，自引：0，他引：4       下载免费PDF全文

吴长江  代宗仰  刘善华 《地质找矿论丛》2006,21(3):199-202

石炭系东河砂岩储层是塔中地区重要的油气产层,通过对岩石铸体薄片、阴极发光薄片、岩心和钻井等资料的综合分析研究认为,岩石颗粒粒度、砂岩厚度以及成岩作用等是影响本区东河砂岩储层物性的主要因素,其中控制储层物性的主要成岩作用有压实作用、胶结作用和溶蚀作用.  相似文献   

某一级公路路基填土膨胀性试验   总被引：1，自引：0，他引：1  

郭军辉  ;阎长虹  ;夏良斌  ;王新明  ;郑军  ;梁清雨 《西安地质学院学报》2007,(1):85-89

通过对某一级公路路基填土的天然含水量、液限、塑限、颗粒组成、矿物成分、自由膨胀率、胀缩总率等试验研究，运用塑性图，并综合各项指标对路基填土的膨胀性做了评价。结果认为，此路基填土为高液限和塑限的淤泥质软土，天然状态下具有弱膨胀性。通过对路基填土的击实试验和承载比试验表明，填土压实之后具有一定的膨胀性，在含水量变化差异性影响下的胀缩变形可能导致路基开裂。  相似文献   

Defending community? Indigeneity, self-determination and institutional ambivalence in the restoration of Lake Whakaki     

Brad Coombes 《Geoforum》2007,38(1):60-72

Conservation practitioners have scrutinized the credibility and effectiveness of community-based natural resource management, noting its romantic misconceptions about communities and their capacities. Early approaches failed to acknowledge the heterogeneity of collective agents, the synergy between decentralization and neoliberalism, or the need to affirm rural peoples’ entitlements to resources. A Maori community’s attempt to restore Lake Whakaki on New Zealand’s east coast confirms many of these critiques. The restoration confronts institutional ambivalence, obstructive forces from beyond the zone of Maori influence and non-correspondence between community and catchment dynamics. Fulfilment of the project requires exogenous resources and authority, but state conservation agencies are ambivalent towards local demands for self-determined development. Nonetheless, an uncommon degree of agency which is grounded within community aspirations for sovereignty suggests that the motivational characteristics of community retain their importance in debates about integrated conservation and development.  相似文献