干熄炉斜道区莫来石-红柱石砖的损毁研究

测试并比较了使用4年后干熄炉斜道区莫来石-红柱石过梁砖不同部位(炉腔侧、风道侧和芯部)砖体的体积密度、显气孔率、耐压强度、化学组成,利用XRD和SEM分别分析了其物相组成和显微结构变化,并对其损毁机制进行了探讨。结果表明:1)莫来石-红柱石砖原始强度较低,易遭受炉体结构应力和热应力破坏;2)与砖体芯部相比,炉腔侧和风道侧受环境气氛影响更大,结构更为疏松,强度下降更明显;3)高温下红柱石莫来石化导致的体积膨胀、低熔点相侵入形成的新物相以及弱还原气氛下SiO2的分解破坏了材料的结合体系,造成了材料致密度的降低和强度大幅下降,是除了炉体结构应力、热应力等因素外,导致干熄炉斜道区莫来石-红柱石砖破坏的不可忽略的因素。     

Inhibition of counterflow methane/air diffusion flame by water mist with varying mist diameter

In the present study, the effect of fine water mist on extinguishment of a methane–air counterflow diffusion flame was investigated to understand the underlying physics of fire extinguishment of highly stretched diffusion flame by water mist. Twin-fluid atomizers were used to generate polydisperse water mist of which Sauter mean diameters were 10, 20, 40, and 60 μm. When water mist is not added, the critical stretch rate at extinguishment is 439 s⁻¹ as compared to the theoretical value of 460 s⁻¹. For the case with water mist addition, when the stretch rate is small enough, almost all the water mist evaporates within the flame zone. On the other hand, for high stretch rate case, large mist droplets pass through the flame zone and can reach the stagnation plane. However, no oscillatory motion was found around the stagnation plane. Critical stretch rate at extinguishment decreases monotonously with the mass fraction of water mist independently of the mist diameter within the range of D₃₂ from 10 μm to 60 μm. On the other hand, with increase in the surface area parameter, the critical stretch rate at extinguishment decreases rapidly and becomes less sensitive at large surface area parameter, of which tendency is qualitatively in good agreement with theoretical predictions. For a constant surface area parameter, the critical stretch rate decreases with mist diameter because the mass fraction of water mist should increase in proportion to the mist diameter to keep the surface area parameter constant. When the water mist evaporates completely in the flame zone as in the present study, the mass fraction of the water mist is the dominant factor for fire extinguishment, rather than the surface area parameter. Therefore, an appropriate combination of stretch rate and water mist mass fraction should be provided to suppress effectively a given fire with a small amount of water mist.     

Design and Engineering of Open Weave Jute Soil Saver for Potential Application in the Field of Soil Erosion Control and Hill Slope Management

Out of several natural agents causing extensive damages to roads, landslides can claim to be a major destroyer. There are several causes for landslides such as hazardous ground conditions, landform configuration adversities, occasionally occurring natural physical forces and anthropogenic impact on the environment. In such vulnerable situations the top soil on hill slopes get disintegrated due to intensive precipitation or shaking due to tremors and eventually flows down rapidly down the slope. The situation deserves the search for a biocover which can reduce the velocity of overland flow and entrap detached soil particles thereby controlling top soil loss. Jute Geotextile (JGT) if properly designed can fulfill the said criteria besides facilitating growth of vegetation. This paper discusses optimization of property parameters of open weave Jute Geotextile in tune with different parameters of design concerning protection of hill slope along with comparative analysis of the results of different tests on one hand and determination of tolerance limit of the prime property parameters of the developed JGT samples, on the other, which have been employed in different case studies to prove their potentiality and technoeconomic viability.     

测井曲线标准化方法研究

由于长岭凹陷区经过近60年的勘探开发,再加上井场井眼条件的差异、测井系列、仪器刻度、测量时间及操作者不同等因素,使得各测井曲线存在系统误差。因此在开展储层参数研究和有效厚度划分时,为消除这些非地层因素对原始资料的影响,有必要对测井曲线进行标准化,以保证解释结果的合理性与可靠性。测井曲线标准化方法可以分为定性和定量两种类型。其中定性方法主要包括直方图法标准化校正、均值法标准化校正和重叠图法标准化校正;定量方法则为趋势面分析校正法。本论文利用Matlab软件,采用趋势面方法对研究区域内的井进行测井曲线标准化。结果表明经过趋势面法标准化校正能够消除不利因素,准确的提取出测井曲线中的各种有用地质信息。     

超大面积混凝土地面结构无缝施工数值模拟研究

随着科技的发展和社会的进步,各种建筑物的规模都在大幅度提升,随之产生的大面积混凝土整体地面在建筑工程中得到了广泛的应用。为了预防和控制大面积混凝土地面裂缝的出现,无缝施工技术得到了越来越广泛的认可。该文以实际工程为依托,对短距离释放应力无缝施工技术进行了研究,利用有限元软件ABAQUS模拟分析施工过程中混凝土水化热与温度的关系,探究相邻混凝土浇筑块的温度传导关系,以期能对类似工程无缝施工起到一定借鉴作用。     

Study of using a multi-touch tabletop technology to facilitate collaboration,interaction, and awareness in co-located environment

This study aimed to evaluate how differently co-located users perform and interact while solving problems by using existing and newly developed interaction mechanisms of a multi-touch tabletop system on a large-size tabletop display. Furthermore, this study aimed to investigate users’ perceived situation awareness due to the system. This study conducted one experiment and introduced three newly developed interaction mechanisms: two-way rubber band, drag-and-response, and centre collection area. Two-way rubber band enables users not only to send but also to request digital objects. Drag-and-response allows users to accept or to reject digital objects sent by others; therefore, it eliminates conflicting situations and interference. Centre collection area stores, organises, and manages shared digital resources on a surface of a tabletop display, so that users have an overall picture of available resources. This paper discusses results of an experiment, research findings, and implications along with conclusions and several suggestions for future development and research.     

The effect of various fire‐exposed surface dimensions on the spalling of concrete specimens

Concrete spalling due to fire exposure is often defined as the sudden detachment of fragments from a concrete surface. It can be quantified by various parameters of which weight loss and spalling depth are the most common ones. The risk of spalling is influenced by many factors such as concrete composition, heating rate and applied testing methods. A reduced scale testing method should be developed to analyse the spalling behaviour and to understand its effectiveness in more detail. As a subsection of this development, this study aimed to analyse the effect of different‐sized, circular heated areas in semi full‐scale fire tests. Therefore, vermiculite slabs with varying cut‐outs in their centre were placed between a specimen made of a spalling‐sensitive concrete and the combustion chamber. The combustion chamber was heated following a standard fire curve. Our experimental results show that the thermal expansion inside of equal‐sized specimens is strongly dependent on the size of the heated area. In addition, this area also affects thermal stresses. They decrease as a result of lower temperature gradients for tests with smaller unheated boundary areas. Apart from this, the analysis of fragments shows no correlation between their relative volume distribution and the heated area. Copyright © 2014 John Wiley & Sons, Ltd.     

岩溶区某锰矿尾矿回填区地下水环境数值模拟预测

针对岩溶区某锰矿尾矿回填区渗漏污染地下水问题进行影响预测,运用数值模拟方法,模拟了污染物在岩溶含水层中的时空分布情况。结果表明:在30年的模拟期内,污染物在回填区下游的最大迁移距离为300m,有9个地下水保护目标受到影响,包括分散式饮用水源井及泉水,但未影响到回填区北部的集中式饮用水源保护区。研究结果可为岩溶区的地下水污染预测提供一定的借鉴。     

多级孔HZSM-5分子筛催化快速热解生物质制芳烃

采用酸和/或碱处理法制备了一系列多级孔HZSM-5分子筛，采用XRD、N₂吸附、XRF、TEM、²⁷Al MAS NMR和NH₃-TPD等表征手段对其孔道结构和酸性进行表征。表征结果表明，采用碱处理方法，可获得孔径集中于3~6 nm的介孔结构，通过改变酸、碱处理次序，可调变酸中心数量和强酸/总酸中心比例。在Py-GC/MS装置上，以纤维素和水稻秸秆为原料，研究多级孔分子筛结构对催化快速热解（CFP）制芳烃反应的影响。反应评价结果表明，同商品级HZSM-5相比，采用先碱后酸处理获得的多级孔HZSM-5分子筛（HZ-OH/H），可将纤维素CFP芳烃碳产率由32.3%提高至43.6%，可将水稻秸秆CFP芳烃碳产率由23.0%提高至30.8%。多级孔HZ-OH/H分子筛的孔道结构和酸中心分布特征，对开发应用于生物质制芳烃的高效工业催化剂具有借鉴意义。     

老旧煤矿健康老龄化环境建设路径分析

被关闭的低效率老旧煤矿,作为很多退休煤矿职工的家庭所在地,依然担负着为其提供正常生活条件和养老功能的任务。为了营造煤炭企业退休职工适老环境,对老旧煤矿健康老龄化环境建设路径进行了探讨。在分析健康老龄化的普遍性问题后,从公共服务、卫生健康服务、认同感、原有养老模式等方面论述了老旧煤矿存在的具体问题;针对现状及问题,从理顺养老服务管理机制和合理确定具体任务目标两方面提出了对策与建议。