Models of CN and C2 comae for comet Tago-Sato-Kosaka and comet bennett

Based on the CN and C₂ comae isophotes for two comets (1961 IX and 1970 16) given by Rahe et al. and the relevant theory of physical chemistry, we have deduced the distributions of the CN and C₂ modecules in the coma, their scale heights and mean lifetimes. The results favour the viewpoint that HCN is the parent of CN, and that C₂H₂ is the parent of C₂.     

Modelling the April 15 spectrum of Supernova 1993 J

We present the modeling of the ultraviolet and optical spectra obtained simultaneously on 1993 April 15 with the HST and at Lick Observatory. A Monte Carlo code is employed in the modeling and a comparison is made between models reported by different groups. With an atmosphere similar to the Sun in chemical composition, the observed spectral lines are well reproduced by a power law density structure of index around 20 except the strong H and HeI λ5876 lines which have peculiar absorption profiles. The photospheric velocity is found to be 9500 km/s and the blackbody temperature of the spectrum is 7990 K. For H and HeI λ5876, we suggest a two-component density structure which has a smoother layer located immediately outside the steeply decreasing inner envelope. The power law indices are most probably 20 and 3, respectively, with the transition point at about 13 000 km/s. In addition, this outer smooth layer serves to flatten the far UV spectrum as observed.     

A THREE-DIMENSIONAL ELASTIC NESTED-GRID MESO-(β-γ)SCALE ATMOSPHERIC MODEL——PARTI:MODEL DESCRIPTION

A three-dimensional elastic nonhydrostatic mesoscale(β-γ)model with nested-grid is presented.It uses a set of fullequations in terrain-following coordinates as its basic dynamic frame,which is solved with a time-splitting algorithmfor acoustic and gravity waves.The model physical parameterization includes a K-theory subgrid eddy mixing for cloudand free atmosphere,a bulk planetary boundary layer parameterization,and three types of sofisticated cloudmicrophysics schemes with double-parameters for hail-bearing clouds,warm clouds and snowing clouds respectively.The model is designed to be used flexibly for simulations of a variety of meso-and small-scale atmospheric processes,and can be improved as a regional and local operational NWP system in future.     

南秦岭十里坪锑矿床成矿时代及成因的初步研究

十里坪锑矿床受赵川陆缘隆_滑构造的主滑脱拆离带的控制。矿体呈脉状赋存于韧_脆性主滑脱带上部的脆性次级断层_节理中,矿石类型主要为萤石石英辉锑矿型。围岩为太古宙_元古宙变质岩系,围岩蚀变弱。成矿流体属H2O_CO2_NaCl体系,流体包裹体盐度w(NaCleq)为3.6%～11.3%,均一温度为109～232℃,形成压力大致为800×105Pa。硫、铅同位素研究表明,矿质主要来源于变火山岩围岩;氢、氧同位素显示,成矿流体以大气降水为主,初步将该矿床定为变质岩源就地式大气降水热液矿床。矿石中萤石Sm_Nd等时线年龄为(392±24)Ma,与南秦岭北部晚古生代拗陷区热水喷流_沉积成矿时代相一致,它们都形成于秦岭微板块泥盆纪非造山裂解阶段。     

基于实测波浪的单桩式海上风电基础波浪力计算研究

基于实测波面的波浪力获取作为结构动力响应分析以及数字孪生模型建立的必备环节,对海上风电数字化运维至关重要。为了满足更大的装机容量需求,单桩式海上风电基础趋于大型化,其尺度因子D/L也随之增大;并且实际海域均为非规则波,以尺度因子划分波浪力计算理论的方法对非规则波的适用性尚不明确。通过建立数值水槽,依据实际工况对不规则波与桩基的作用进行数值模拟,得到入射波浪场与桩基所受波浪力,在此基础上,基于入射波浪场分别采用Morison方程以及绕射理论求解波浪力并将之与数值模拟结果进行对比,分析了不同波浪力计算理论关于尺度因子的适用性,同时探究了波浪要素对计算精度的影响。结果表明：Morison方程在波高较大时精度下降;相对于Morison方程,绕射理论在该尺度下的精度更高。最后,通过分析实测数据进一步探讨了典型工况下的波浪力特征,以期通过实测波面计算波浪力的方法为实际服役风机波浪力计算提供技术支持。     

西北太平洋九州-帕劳海脊北部KPR12岩芯40万年来有机碳来源、埋藏特征及其环境响应

西北太平洋海陆相互作用强烈,受黑潮和亚洲大陆风尘输入影响显著,是研究海洋沉积物中有机碳埋藏与陆源输入、海洋初级生产力和海洋环境演化关系的理想靶区。本研究基于采自九州-帕劳海脊北部的重力活塞647 cm长的KPR12岩芯,分析了总有机碳（TOC）、总氮（TN）、有机碳稳定碳同位素组成（δ¹³C_TOC）、蛋白石（Opal）以及粒度等指标,初步探讨了近40万年来轨道尺度沉积有机碳的来源、埋藏特征及其影响机制。岩芯的TOC含量平均值为0.214%,呈冰期较高、间冰期较低的旋回特征。岩芯沉积物粒度的不同端元反映了研究区风尘输入大致呈冰期较高的趋势。岩芯的δ¹³C_TOC（-25.24‰~-21.04‰,平均值为-22.59‰）显示有机质以海源为主（约62%）,海源有机碳含量趋势与TOC的变化一致。研究区不同时期陆源物质的输入受风尘输送和黑潮的综合控制,黑潮增强可能对该区间冰期陆源有机碳贡献的升高有一定影响。岩芯中TOC与Opal含量的相关性分析表明,海洋初级生产力可能不是控制该岩芯有机碳含量变化的主要原因。冰期-间冰期旋回中的深层水通风条件、黑潮和北太平洋中层水的发育以及陆源细颗粒物质输入可能共同影响着本区沉积有机碳的降解与埋藏保存。

     

On the exact solutions and invariant rays of the phase plane in Brans-Dicke theory

On the basis of the model properties of the expansive nondecelerative universe, present temperature of cosmic microwave background and specific entropy in the era of matter, the present parameters of our Universe may be exactly determined.     

Heavy metal pollution in sediments of a typical mariculture zone in South China

The heavy metal inventory and the ecological risk of the estuarine sediments in Hailing Bay, an important maricultural zone along the southern coast of China, were investigated. Results show that the surface sediments were mainly polluted by As (2.17-20.34 mg/kg), Ni (1.37-42.50mg/kg), Cu (1.21-58.84 mg/kg) and Zn (11.69-219.22 mg/kg). Furthermore, the aquafarming zone was significantly more polluted than the non-aquafarming zone, and cluster analysis suggested additional sources of heavy metal input in the aquafarming zone. As, Cr, Cu, Ni, Pb and Zn were mainly present in the non-bioavailable residual form in the surface sediments, whereas Cd was predominantly in the highly mobile acid soluble and reducible fractions. The ecological risk of the polluted sediments stemmed mainly from Cd, and from As, Cu and Pb to less degrees. The highest potential risks occurred near the aquaculture base, indicating the need to control heavy metal inputs from aquafarming activities.     

从中下三叠统膏盐特征看中下扬子早印支运动

中下扬子早 中三叠世膏盐层是对早印支运动的沉积响应,本文从膏盐的成因、中下扬子膏盐层位的差异、沉积环境的变迁、膏盐的厚度变化和产状特征、沉积中心和沉降中心的分布等方面,分析早印支运动的表现形式。中下扬子早 中三叠世依次出现陆棚台地（碳酸盐岩）、潟湖—潮坪（白云岩与膏盐）和滨海（碎屑岩）,这种大规模海退,正是早印支运动表现为构造抬升的结果。抬升过程中,残留海水在炎热干燥的气候条件下蒸发形成膏盐层,而中扬子的膏盐层位比下扬子低,据此推测中扬子先于下扬子与华北板块碰撞而抬升。平面上,现今构造格局（主要由中印支—早燕山运动形成复向斜、复背斜和推覆构造）的坳陷区主要为白云岩与（硬）石膏互层或石膏夹少量白云岩或云质石膏,膏盐层厚度大,现今构造的隆坳过渡区主要为石膏假晶、含膏云岩、石膏质白云岩、白云岩夹石膏等,膏盐层厚度小,而膏盐的厚度和产状与沉积时的水深和地势直接相关; 另外,地层等厚图显示膏盐层主要分布于当时的沉降中心。这些沉积特征显示膏盐沉积时的地势与现今隆坳相间的构造地貌存在一定程度的吻合,说明膏盐沉积时的地层已经发生了轻微的褶皱变形（未见角度不整合和地层缺失）。     

潼峪金矿区成矿断裂构造特征

潼峪金矿区发育过冲剪滑型、平移剪张型和平移剪滑型三种不同性质、不同方向成矿断裂,分布在金罗斑背形的不同部位,其形成有先后差异,但变形环境大体相同,具脆-韧性变形特征。空间上一般不超越褶皱主体。三类断裂中,前两者具石英脉型金矿化,后者形成构造蚀变岩型及小规模石英脉型金矿化。矿化差异与断裂产出的褶皱部位及其相应的应力应变条件的不同有关。