Post failure behaviour of a rock mass under the influence of triaxial and true triaxial confinement

In this paper results of triaxial and true triaxial testing conducted on physical models of a rock mass are used to describe its post failure behaviour. The specimens comprised of three continuous joint sets and were prepared from blocks of sand lime model material. The testing was performed using a True Triaxial System (TTS) developed by the authors. The results show strain hardening, strain softening and plastic behaviour in the simulated rock mass specimens depending upon joint geometry and stress state. Expressions are suggested to estimate post peak modulus in triaxial and true triaxial stress conditions. Finally, a zonation table is proposed to assess the strain hardening, softening and plasticity behaviour of a rock mass material with the help of joint geometry and confining stress conditions at site.     

Testing the application of post IR IRSL dating to Iron- and Viking-age ceramics and heated stones from Denmark

In this study we test, for the first time, the potential of an elevated temperature post-IR IR (pIRIR₂₉₀) SAR protocol for the dating of young heated artefacts. Seven heated stones and seven potshards were collected from three different archaeological sites in Denmark: one site from the early Pre-Roman Iron Age 200 BC to AD 100, and two from the Viking period between AD 800 and 1200.We first derive quartz OSL ages for these samples, to support the archaeological age control. The luminescence characteristics of the pIRIR₂₉₀ signal are then investigated; in particular the dose recovery ratios are shown to be close to unity. The performance of the feldspar pIRIR₂₉₀ protocol is then examined by comparing the pIRIR₂₉₀ ages with those based on the quartz OSL signal; the average ratio of pIRIR₂₉₀ to OSL ages is 1.14 ± 0.05 (n = 14) and there is some suggestion that the possible overestimation of the feldspar ages compared to quartz is only of significance for the heated stone samples. Nevertheless, there is no indication of incomplete heating of the stones; the ratios of D_e derived from the IR₅₀ and pIRIR₂₉₀ signals are independent of sample type, and consistent with complete resetting by heating. Comparison with the archaeological age control is not able to identify whether quartz or feldspar provides the most reliable dating signal.     

Thermally re-distributed IRSL (RD-IRSL): A new possibility of dating sediments near B/M boundary

This study attempted to probe a geologically more stable IR stimulated luminescence signal (IRSL) that explored so far. IRSL, probes the proximal pairs and, pIRSL measurements at elevated temperatures consume more distant pairs. We surmised that the residual IRSL after pIR-IRSL should arise from most distant pairs and hence should be more stable. A thermal stimulation after pIR-IRSL leads to redistribution of charges including distant pairs and this can be probed by further IRSL and pIRSL (post IR IRSL) measurements. This post IRSL following a thermal treatment is termed as redistributed IRSLs (RD IRSL and RD pIRSL) and contributes about 10% of total IRSL counts from a pristine sample. As expected RD, IRSLs are poor to be solar bleachable. Burial age of around 800 ka(with 30–40 %) using RD-IRSL and RD-pIRSL were comparable with the palaeomagnetic dating and were a factor of three higher than conventional pIR-IRSL, TRL, IR-RL and VSL ages.     

A review of animal welfare implications of the Canadian commercial seal hunt – a response to critique of paper MP13 172

Canada's commercial seal hunt warrants close examination in that it is the largest kill of marine mammals on earth, it exists for commercial reasons, it targets deep diving seals with unique physical adaptations, and it is conducted in a particularly remote and uncontrolled environment amidst unstable sea ice and extreme weather conditions. For these reasons, commercial sealing in Canada has been the subject of regular veterinary scrutiny for more than five decades. In that time, despite repeated recommendations and some changes to the regulations, considerable evidence continues to be presented during each new season of poor welfare outcomes for seals.To add to the discussion we (Butterworth and Richardson) (2013) [1] reviewed multiple studies on commercial sealing, government reports, trade journal articles and recommendation reports, in an attempt to answer the question of why, despite the efforts of veterinary advisors and government to improve the situation, seals continue to die in inhumane ways. In examining the available evidence, the environment in which commercial sealing occurs, and the physical adaptations of seals, the authors concluded that generally accepted principles of humane slaughter cannot be implemented effectively and consistently in the context of commercial sealing.     

东北三省城市人居活动网络结构及影响因素分析——基于百度贴吧分析

人居活动是城市网络的根本,探究城市人居活动网络结构对促进区域协调发展具有重要的实践意义。论文利用百度贴吧数据分析城市人居活动,运用社会网络分析法等研究方法探究城市人居活动网络体系,并通过QAP论文相关及回归分析对城市人居活动网络结构影响因素进行初步分析。结果表明：① 整体网络方面,人居活动区域联系密度为95.99%,东北三省城市之间普遍存在联系;城市联系类型可划分为全域型、普遍型、较多型、一般型以及较少型五种类型;② 层级结构方面,东北三省省内人居活动网络层级较为明显,区域范围内尚未形成主导型城市及次级主导型城市;③ 城市体系方面,省内人居活动网络体系较为完备,形成了较为明显的城市网络体系;④ 影响因素方面,旅游资源、行政关系、空间邻近及收入水平对城市人居活动网络结构产生显著影响。     

区域发展理论:回顾与展望

区域发展理论是经济地理学和区域科学基础理论的核心。本文首先回顾了传统的区域发展理论, 包括发展阶段理论、均衡增长理论、不均衡增长理论、区域增长的一般理论模式和新马克思主义理论, 然后概述了70 年代以来区域发展理论研究的新进展, 最后前瞻了区域发展理论研究与发展的基本方向。     

Fammenian–Tournaisian dextral ductile shear in the French Variscan belt

The South Armorican Shear Zone consists of a set of faults that runs across the southern Armorican Massif and extends eastwards to the Massif Central. One of its branches, the Cholet Shear Zone of South Brittany, can be correlated with the North-Millevaches–La Courtine Shear Zone in the Massif Central. It was active immediately after the regional Frasnian anatexis (372–368 Ma) as a right-lateral strike-slip fault. The horizontal offset, which can be estimated between 110 and 170 km, was achieved before the emplacement of non-deformed Late Tournaisian calc-alkaline and peraluminous granites (355–350 Ma). This newly established age of activity (Fammenian–Tournaisian) of the Cholet–La Courtine Shear Zone (CCSZ) has to be taken into account in geodynamical reconstructions of the Variscan belt of western Europe. To cite this article: C. Cartannaz et al., C. R. Geoscience 338 (2006).     

渤海涟虫类和软体动物幼虫食性的观察

根据消化道内食物分析结果得出：涟虫类、三叶针尾涟虫和驼背涟虫、瓣锶类后期幼虫和腹足类后期幼虫都营浮游植物食性,以硅藻类为主要食物。细长涟虫以星脐圆筛藻、未查明的圆筛藻和辐射圆筛藻为主要摄食对象;三叶针尾涟虫以舟形藻和新月菱形藻为主要摄食对象;驼背涟虫以辐射圆筛为主要摄食对象。鳃类后期幼虫以辐射圆筛藻和未查明的圆筛藻为主要摄食对象;腹足类后期幼虫以未查明的圆筛藻、辐射圆筛藻和中心圆筛藻为主要摄食对象     

深海载人潜水器潜航员培养模式探究

为了加快建立深海载人潜水器潜航员体系,实现深海载人潜水器业务化运行,提高我国载人深潜科考作业水平,文章结合"深海进入、深海探测、深海开发"战略需要,分析研究了载人潜水器作业环境、作业需求和潜航员岗位要求。提出了能力、知识、技能三位一体化的培养模式和基于专家系统课程设置架构,实践表明该培养模式科学、严谨,极大地推动了"蛟龙"号载人潜水器潜航员队伍的培育,对未来我国深海载人潜水器潜航员培养具有重要的指导意义。结合培训的实际情况,让潜航员培养工作顺利开展,提出构建科学的管理体制、完善潜航员培养保障机制、建立系统的制度保障制度等建议。     

矿床变化与保存研究的裂变径迹新途径

矿床形成后的变化与保存是矿床学研究与找矿勘探中一项极其重要但仍需进一步加强的基础性工作。影响矿床变化与保存的众多因素中,区域隆升与剥蚀是最为关键的因素之一。裂变径迹法是研究区域隆升与剥蚀的一种有效手段,它能为我们提供剥蚀速率以及剥蚀量的定量数据。一些产于花岗质岩体内与岩体有成因联系的矿床,其成矿深度可以通过详细的流体包裹体研究来获得。通过成矿深度与岩体剥蚀深度对比分析,能使我们更好地了解矿床形成后变化保存条件。裂变径迹法与流体包裹体研究相结合是矿床形成后变化与保存研究一种切实可行的方法。