构造附加动力对煤变质过程的影响

本文从固体力学、构造物理化学的角度分析了煤岩所受应力的来源、性质以及应力在煤变质过程中的影响方式。作者在前人研究基础上,阐述了构造动力影响过程中煤岩能量的转换形式,分析了应力在烟煤分子团聚过程中的影响。研究认为,煤岩所受的各种应力(压应力、拉应力、剪应力)为地层压力与构造动力所造成的附加内力。这种附加内力可以分解为构造附加静水压力与偏应力两部分。构造附加静水压力主要影响煤岩的物理性质,如孔隙度、颗粒性质与瓦斯吸附特征,并对煤的化学煤化过程有缓慢促进作用。偏应力主要使煤岩发生变形和位移。煤化过程中,由构造运动所产生的动能转化为各种形式的热能、表面能、弹性变形能以及声、光、电、磁等形态能量。     

霍尔果斯背斜深井井身结构优化设计

霍尔果斯背斜受山前构造的影响,存在地质情况复杂、倾角大、多套压力体系并存以及泥岩含量高等问题,在钻进过程中复杂事故频发,严重制约了该地区油气勘探开发的进程。通过对完钻井的测井资料、地破实验数据、钻井复杂等资料的分析,确定必封点位置,形成适合霍尔果斯背斜深探井的四开井身结构,并针对安集海河组复杂事故率高的情况,采用高密度油基钻井液抑制泥岩水化,从而实现安全钻进。优化后的井身结构在霍尔果斯背斜深探井H11井进行了应用,首次实现了在安集海河组、紫泥泉子组两套压力系统下进行套打,历时5.5 d钻穿“死亡之海”安集海河组,未出现井漏现象,取得了良好的应用效果。优化后的井身结构在H11井的成功应用,不仅为该地区深探井的井身结构设计提供依据,也为该地区后续常规井的四开转三开井身结构提供了指导。     

东海盆地西湖凹陷油岩地球化学特征及原油成因来源

东海盆地西湖凹陷具有大量的原油资源,但对于原油成因讨论较少.采集西湖凹陷多个油样和岩样,利用气相色谱和傅里叶红外光谱等手段,全面分析了该区烃源岩和原油的地球化学特征,综合讨论了原油来源以及凝析油和高蜡轻质油的成因.研究结果表明,平湖组煤系源岩均处于热演化的成熟阶段,其中碳质泥岩和煤岩以陆源生物为主要生源,其干酪根类型为Ⅲ型,暗色泥岩则具有陆源生物和水生生物双重生源贡献,其干酪根类型Ⅱ-Ⅲ型,同时碳质泥岩和煤的生油潜力远高于泥岩.原油主要为凝析油和轻质油,凝析油具有低密度、低蜡等“六低一高”的特点,轻质油具有高蜡特质,而且轻烃组分有明显差异.生标参数显示大部分原油为腐殖型,少部分原油表现出具有腐殖和腐泥母质的特点,同时该区原油均处于中等成熟阶段.油油对比和油岩对比表明大部分油来自平湖组碳质泥岩和煤岩,具有典型Ⅲ型腐殖油的特征;少部分油来自暗色泥岩,具有Ⅱ-Ⅲ型油的特征(总体上仍偏腐殖型).凝析油和轻质油的物性及轻烃组分的差异与源岩母质无关.凝析油是干酪根在成熟演化阶段生成的原油遭受蒸发分馏作用的结果,高蜡轻质油除了是“蒸发分馏作用”的残余油外,还有部分是“混合作用”的结果.      

隐伏岩溶区地下空间探测技术方法研究——以武汉市为例

岩溶地面塌陷是城市隐伏岩溶区地下空间开发过程中常见的地质环境问题,具有隐蔽性和突发性,开展隐伏岩溶区地下空间结构探测技术方法研究可以有效指导地下空间开发利用。以武汉市为例,分析武汉市岩溶地面塌陷的成因机理,提出岩溶发育程度、覆盖层厚度和结构、地下水是岩溶地面塌陷的原生地质条件,也是隐伏岩溶区地下空间探测的特征因子。通过对比分析地质雷达、高密度电阻率法、浅层地震、微动、混合源面波、瞬变电磁法、孔间层析成像和地面核磁共振法等技术方法在武汉市隐伏岩溶区地下空间探测的适用性。结果表明：地质雷达适用于浅部土层扰动探测,小极距的高密度电阻率法和混合源面波适宜于覆盖层的厚度和结构探测,浅层地震、微动和孔间层析成像适宜岩溶发育特征探测,地面核磁共振法可通过岩溶地下水的富水性辅助岩溶发育程度探测。     

靶场测量装备中GPS换装北斗卫星导航系统方案设计

目前,根据装备试验要求,利用北斗卫星导航系统全面替换靶场测量装备中所使用的GPS已成为必须开展的工作。如果直接替换,则现有测量系统需重新进行测试,代价较高。为此,结合靶场测量装备实际情况,设计一种基于北斗卫星导航系统,集定位、测姿、授时为一体的便携式信息采集分发系统,系统具备多种对外数据传输接口,无需对现有装备进行较大改造,即可全面实现北斗取代GPS的目的。     

Impact of Wind on Tide-Induced Advective Salt Transport in A Well-Mixed Estuary

The tide-induced net advective salt flux in well-mixed estuaries consists of five terms according to the method from Kjerfve.The term resulted from the vertical variation in salinity can be negligible in well-mixed estuaries with four tide-induced salt flux terms,known as F1?F4.To explore the effects of wind on these salt fluxes,the current-salinity analytical model combined with the perturbation analysis is extended by including wind.Analytical expressions for the four salt fluxes are derived separately in the present model.Under the assumption that only the M₂ tidal component is accounted for and the salt flux generated by diffusion is not studied,the tide-induced net advective salt flux Q_sx is in the seaward direction without the wind effect.By applying the Western Scheldt estuary case,the wind influence on the tidal advection salt flux(TASF)distribution in the F4 term was investigated.The phase difference between zero-order velocity and first-order salinity(Δφ)at the surface layer of the estuary is larger than 90°and smaller than 90°at the bottom layer,which leads to landward TASF in the surface layer and seaward TASF in the bottom layer.The distribution ofΔφis not uniform in the horizontal direction with wind included,which differs from the result without wind.In the case of seaward wind with the speed of 18 m/s,the decrease in the zeroth-order velocity phase(φu)at the surface layer is larger than that of the first-order salinity phase(φs)downstream,which leads to an abnormal seaward TASF in this region.Owing to the surface stress caused by wind,the Stokes compensation flow in the middle and lower reaches increases/decreases with the increase of the landward/seaward wind,while the upstream situation is opposite.Thus,the first-order velocity in the middle and lower reaches increases/decreases with the increase of the landward/seaward wind,while the upstream situation is also opposite.The first-order salinity also increases/decreases with the increase of landward/seaward wind,while the upstream salinity tends to zero.Therefore,the tide-induced net advective salt flux Q_sx increases/decreases with the increase of the landward/seaward wind,which is contrary to the usual recognition.     

基于背景噪声互相关技术的海底地震仪的时钟校正方法在西南印度洋脊的应用

Seismic monitoring using ocean bottom seismometers(OBS) is an efficient method for investigating earthquakes in mid-ocean ridge far away from land. Clock synchronization among the OBSs is difficult without direct communication because electromagnetic signals cannot propagate efficiently in water. Time correction can be estimated through global positioning system(GPS) synchronization if clock drift is linear before and after the deployment. However, some OBSs in the experiments at the southwest Indian ridge(SWIR) on the Chinese DY125-34 cruise had not been re-synchronized from GPS after recovery. So we attempted to estimate clock drift between each station pairs using time symmetry analysis(TSA) based on ambient noise cross-correlation. We tested the feasibility of the TSA method by analyzing daily noise cross-correlation functions(NCFs) that extract from the data of another OBS experiment on the Chinese DY125-40 cruise with known clock drift and the same deployment site. The results suggest that the NCFs' travel time of surface wave between any two stations are symmetrical and have an opposite growing direction with the date. The influence of different band-pass filters,different components and different normalized methods was discussed. The TSA method appeared to be optimal for the hydrophone data within the period band of 2–5 s in dozens of km-scale interstation distances. A significant clock drift of ~2 s was estimated between OBSs sets through linear regression during a 108-d deployment on the Chinese cruise DY125-34. Time correction of the OBS by the ambient noise cross-correlation was demonstrated as a practical approach with the appropriate parameters in case of no GPS re-synchronization.     

双层直立圆弧型防波堤上绕射波浪力的解析计算

基于微幅波绕射理论,应用特征函数展开法,推导了双层直立圆弧型透空防波堤的波浪绕射解析解,从而将已有的比例边界有限元法拓展为解析算法,并据此对外层与内层防波堤所受波浪载荷进行了解析计算。计算结果表明:应用本文方法对直立透空圆环柱的绕射波浪载荷进行验证计算,所得结果与现有的解析解完全吻合,说明方法可靠。双层堤较单层堤能更有效地减弱波浪作用。波浪的入射角度和特征参数、防波堤张角与半径、防波堤透空系数以及水深等因素的相对变化对双层堤的波浪作用均存在一定影响。     

蛋白质精氨酸甲基转移酶1调控DNA损伤修复和细胞凋亡

蛋白质精氨酸甲基转移酶1 (protein arginine methyltransferases 1, PRMT1)是PRMT家族中的重要一员,属于Ⅰ型PRMTs,细胞内超过85%的蛋白质精氨酸的甲基化由其催化。PRMT1通过调节底物的甲基化水平,从而调控蛋白的功能及蛋白参与的细胞活动和生理过程,包括细胞信号转导,DNA损伤修复,转录调控,RNA代谢,蛋白质相互作用等。本文着重讨论PRMT1的结构、底物及其在DNA损伤修复和细胞凋亡中的功能。     

Study of the comprehensive risk analysis of dam-break flooding based on the numerical simulation of flood routing. Part I: model development

Dam-break floods have been of increasing concern to safety engineers and decision makers. The presence of complex terrain in inundation areas multiplies the simulation difficulty of flood routing. In previous studies, representing the flood routing parameters empirically does not reflect the characteristics of flood routing, which strongly influences the accurate assessment of the dam-break consequences. The basis for carrying out dangerous reservoir reinforcement is just engineering safety, without considering the actual situation of downstream areas. In this study, a comprehensive risk analysis of the dam-break flood was implemented based on the numerical simulation of flood routing. First, coupled with the volume of fluid method, a three-dimensional k–? turbulence mathematical model was developed for flood routing in complex inundation areas. Then, based on the flow parameters obtained through computational fluid dynamics modeling, the attribute measure methodology was used for the evaluation of consequences combined with the calculation of the dam-break consequences (loss of life, economic loss, social and environmental influence). Furthermore, a methodology containing the combined weight method and the technique for order performance by similarity to ideal solution method was proposed for risk ranking of dangerous reservoirs due to its logical consideration of scalar values that simultaneously account for both the best and worst alternatives. Finally, a sensitivity analysis was performed to provide information about the stability of risk ranking. The aforementioned model and methodology are applied to a case involving five reservoirs in the Haihe River Basin in China for Part II of this study.