二氯乙烷和氯乙烯单体的市场分析与生产技术

评述了二氯乙烷（EDC）的世界产能和需求、氯乙烯单体（VCM）的世界产能、近期EDC和VCM的扩能项目和生产技术进展，以及我国EDC和VCM装置的建设近况。     

基于经验公式建立的滑坡泥石流坝溃口形式预测模型

为了预测滑坡泥石流坝溃决产生的洪峰流量和最大水深,本文的目标是建立滑坡泥石流坝在自然条件下首次溃决形式的经验公式模型,包括平均宽度bc和残留高Hd两个溃口形式的特征参数,从而为制订防灾减灾方案或应急预案提供科学依据。通过野外考察采集的数据以及溃决特征分析,选取影响滑坡泥石流坝溃口形式的主要因子,分别建立了坝高H、有效坝长B、堰塞湖库容W、坝体鞍部单宽体积V、内摩擦系数tan 以及上限粒径d90共6个因子与溃口形式（即溃口的平均宽度bc和残留高Hd）之间的经验关系公式。最后,将经验预测公式运用到实例进行检验,误差较小。     

斐波那契图及其定理

一个图G被称为斐波那契图,如果可以给它的项点分配非负整数,使得由分配给每条边的端点的数之和所得到的边的值能够排成一个斐波那契数列1,1,2,3,5,8,13,21,34…Fn.我们证明了路、圈及完全图KP是斐波那契图的充要条件.     

煤炭地下气化发展现状及趋势

依据有关文献和调研资料，对国内外煤炭地下气化的发展历史及现状进行了介绍，例举了国内外一些重要地下气化试验及典型煤气组成和煤气的热值情况．分析了国内外地下气化存在的问题，提出了今后应该发展的方向．     

On the notch sensitivity of flax fibre metal laminates under static and fatigue loading

Damage progression and failure characteristics of open‐hole flax fibre aluminium laminate (flax‐FML) specimens subjected to quasi‐static tensile or tension‐tension fatigue loading were experimentally investigated. Notched and unnotched flax‐FML composites exhibited brittle fracture with little or no fibre pull‐out and minimal delamination at the aluminium/adhesive interface. The flax‐FMLs were tested to failure under tension‐tension fatigue loading conditions (R ratio of 0.1; frequency of 10 Hz; applied fatigue stresses ranging between 30% and 80% of the respective ultimate tensile strength values). The fatigue cycles to failure decreased with the increase in the applied fatigue stress and hole diameter. A phenomenological modelling technique was developed to evaluate the fatigue life of an open‐hole flax‐FML composite. Fatigue tests on specimens subjected to a maximum load equivalent to 35% of the respective tensile failure strength were interrupted at around 85% of the corresponding fatigue life. The accumulated fatigue damage in these specimens was characterised using X‐ray computed tomography. For benchmarking purposes, the fatigue performance and related damage progression in the flax‐FML composite were compared with those of the glass‐FMLs.     

金沙江白格堰塞湖溃决过程数值模拟

2018年10月10日和11月3日，在我国四川省与西藏自治区交界处的白格村同一位置连续发生两次滑坡，完全堵塞了金沙江形成堰塞湖。由于“10?10”滑坡形成的堰塞湖水位抬升迅速，堰塞湖于10月12日自然漫顶溃决。“11?03”滑坡堵塞了“10?10”堰塞体溃决形成的流道，形成了更大的堰塞湖，鉴于客观条件允许，采取了开挖泄流槽降低堰塞湖溃决水位的措施，至11月12日，堰塞湖发生漫顶溃决，溃口洪水峰值流量为31000m3/s。由于“11?03”白格堰塞湖溃决案例拥有较为完整的实测资料，为堰塞湖溃决过程的研究提供了宝贵的基础数据。基于堰塞体的溃决机理，建立了可考虑堰塞湖的水动力条件、堰塞体的形态和材料特征的堰塞湖溃决过程数学模型。模型采用宽顶堰公式模拟溃口洪水流量，并根据堰塞湖入湖和溃口流量以及堰塞湖的水位-湖面面积关系曲线确定堰塞湖水位的变化；采用基于水流剪应力和堰塞体材料临界剪应力，并可考虑宽级配堰塞体材料特性的冲蚀公式模拟材料的冲蚀过程；假设溃口在纵向下切和横向展宽过程中坡角保持不变，采用极限平衡法分析溃口在发展过程中发生的边坡失稳；采用按时间步长迭代的数值计算方法模拟堰塞湖溃决时的水土耦合过程。采用建立的模型对“11?03”白格堰塞湖溃决案例进行反演分析后发现，模型计算获得的溃口流量过程、堰塞湖水位变化过程、溃口发展过程与实测值基本吻合。参数敏感性分析表明，冲蚀系数对溃决过程具有重要的影响，残留坝高通过影响下泄库容也对溃决过程产生作用；另外，开挖泄流槽可降低堰塞湖溃决时的库容，从而对溃口流量过程产生影响，是降低灾害损失的有效手段。     

eMediator: A Next Generation Electronic Commerce Server

This paper presents eMediator , an electronic commerce server prototype that demonstrates ways in which algorithmic support and game–theoretic incentive engineering can jointly improve the efficiency of e–commerce. eAuctionHouse , the configurable auction server, includes a variety of generalized combinatorial auctions and exchanges, pricing schemes, bidding languages, mobile agents, and user support for choosing an auction type. We introduce two new logical bidding languages for combinatorial markets: the XOR bidding language and the OR–of–XORs bidding language. Unlike the traditional OR bidding language, these are fully expressive. They therefore enable the use of the Clarke–Groves pricing mechanism for motivating the bidders to bid truthfully. eAuctionHouse also supports supply/demand curve bidding. eCommitter , the leveled commitment contract optimizer, determines the optimal contract price and decommitting penalties for a variety of leveled commitment contracting mechanisms, taking into account that rational agents will decommit strategically in Nash equilibrium. It also determines the optimal decommitting strategies for any given leveled commitment contract. eExchangeHouse , the safe exchange planner, enables unenforced anonymous exchanges by dividing the exchange into chunks and sequencing those chunks to be delivered safely in alternation between the buyer and the seller.     

改进的集对分析法在溃坝社会影响评价中的应用

针对传统集对分析法存在着评价语过粗、集对势无法处理c=0、判定准则判定评价等级时会损失大量有用信息等不足,采用联系度可展性、广义集对势、置信度准则对其进行优化改进。在分析溃坝社会影响的主要因素、建立评价指标体系的基础上,构建了基于改进集对分析法的溃坝社会影响评价模型。将该模型应用于刘家台水库溃坝社会影响评价,并与其他评价方法进行对比分析。结果表明刘家台水库溃坝社会影响评价等级为“严重”,与实际情况更为贴近。该改进方法具有较好的可靠性与合理性,为溃坝社会影响评价提供了一种新方法。     

堰塞湖溃坝快速定量风险评估方法——以2014年鲁甸地震形成的红石岩堰塞湖为例

2014年8月3日云南昭通市鲁甸县发生6.5级地震,形成高83 m,库容2.6亿m³的红石岩大型堰塞湖,严重威胁上下游生命财产安全。由于震后地质条件恶劣,道路堵塞,环境危险,且堰塞坝寿命极短,现有方法很难在有限时间内对堰塞坝进行快速且定量风险评估。本文提出一套基于最基本的堰塞坝几何参数、河道三维地形信息和人口分布数据的快速定量风险评估方法,可以实现任何堰塞坝突发区域内的溃坝、洪水演进和生命损失分析:首先采用地理信息工具快速获取坝址、上下游河道三维地形信息;然后采用统计模型和HEC-RAS软件模拟溃坝和洪水演进过程;最后采用风险分析模型计算得到下游生命损失。本文将该方法应用于红石岩堰塞湖案例分析发现:开挖泄流槽可以降低峰值流量和生命损失,但不能防止溃坝;开挖泄洪支洞后,可以避免在非汛期情况下发生溃决;但在极端洪水情况下(如百年一遇)仍会发生溃坝,并产生较大的洪水和生命损失,因此仍需要加固坝体,做好观测,并准备好应急预警和疏散预案。本方法可针对突发堰塞湖进行快速定量的风险评估,为堰塞湖的应急管理和决策提供依据。     

Effects of upstream and downstream slopes and clay content on levee's breaching by overtopping

The present study investigated the effects of clay content and levee's slopes on the breach formation process for levees constructed by both cohesive and non‐cohesive soils. Twelve experiments were carried out and the breach formation of levees was observed by measuring the breach discharge variations and scour topography with time. The initiation of surface erosion was analysed by comparing the estimated bed shear stress and the critical soil shear stress, and the rate of erosion during breaching was estimated by employing the erosion index. The erosion of levees due to overtopping was classified into three regimes of uniform surface erosion, erosion from the toe, and single scour formation. It was found that the upstream levee's slope had negligible effects on the breach process, whereas the downstream slope significantly increased the erosion index. The peak breach discharge increased with increasing downstream slope and it occurred earlier. Experimental results also showed that the peak breach discharge was higher in non‐cohesive levees than the cohesive embankments and it occurred much earlier. Based on dimensional analysis, empirical equations were proposed to predict the breach discharge and the topography of erosion during the breach.