隧道窑预热带烟气流动对上下温差的影响

为减小隧道窑预热带上下温差,利用计算机数值模拟对预热带温度场进行研究,找出烟气流动对隧道窑预热带上下温差的影响规律.在预热带内来流烟气的温度保持不变,速度为0.5～1.0 m/s时,窑内温度均匀性较好.在保持来流烟气温度和速度不变的情况下,码料密度的合适值为孔隙率在0.208～0.408范围内,可提高产品的质量和产量.     

Deformation and failure study of surrounding rocks of dynamic pressure roadways in deep mines

In order to understand the change rules of stress-displacement in surrounding rocks of dynamic pressure roadways in deep mines and to obtain a theoretical basis for analyses of roadway stability and designs of support,we established a coupling equation of adjacent rock strength,mining stress and supporting resistance on the basis of an elastic-plastic theory of mechanics.We obtained an analytical solution for stress and displacement distribution of elastic and plastic regions in surrounding rock of dynamic pressure roadway..Based on this theory,we have analyzed the changes in stress-displacement in elastic and plastic regions of surrounding rocks of dynamic pressure roadways in the Haizi Coal Mine.The results show that:1) radial and tangential stress change violently within the first 4 m from the inner surface of a roadway after excavation;radial stress increases while tangential stress decreases within a range of about 6 m from the inner surface of the roadway as a function of q3;2) radial and tangential stress increase with an increase in the mining pressure coefficient k;the increase in the rate of tangential stress is greater than that of radial stress;3) the radial displacement of the inner surface of roadways decreases with an increase in q3,provided that k remains unchanged.     

Effect of cooling rate on the phase transformation and stability of the mushy zone during the solidification of Waspaloy

Scanning electron microscopy(SEM) and energy dispersive X-ray analysis(EDAX) were used to study the microstructure,microsegregation, and fluid flow tendency of the superalloy Waspaloy in the mushy zone,which had been solidified at different cooling rates. The investigation was accompanied with the calculation of Rayleigh numbers.It is found that Ti is the main segregating element and the content of Ti is the highest in the final liquid at the cooling rates of 3-6℃/min.The eta phase(η) precipitate present...     

桂东大瑶山地区金矿床的成矿构造类型及其成矿指示

广西大瑶山地区金矿的成矿构造类型可分为两大类：一类为流体型成矿构造,另一类为构造型成矿构造。其中：流体型成矿构造有流体脉型、流体角砾岩型及流体细脉型;构造型成矿构造有构造蚀变岩型、构造脉型。构造解析后认为：桃花金矿床的控矿构造（指控制成矿构造的构造）为伸展型脆-韧性剪切带,早期成矿构造类型主要为流体脉型,晚期为构造蚀变岩型;古袍志隆金矿床的控矿构造为逆-平型脆-韧性剪切带,早期成矿构造类型为流体细脉型、流体脉型,晚期为构造蚀变岩型;古袍湾岛金矿床的控矿构造为发育于顺层侵位花岗斑岩中的脆性破裂带,早期成矿构造类型为流体细脉型,属雏形成矿构造（控制特富金矿包）,晚期为构造蚀变岩型;龙水金矿床的控矿构造为走滑型脆-韧性剪切带,其成矿构造类型为流体脉型;六岑金矿床的控矿构造为与隐伏酸性岩体侵位有关的节理-断裂型脆性破裂构造,其成矿构造类型为构造脉型及构造蚀变岩型。基于对该区金矿床成矿构造类型的划分及控矿构造类型的研究,本文对广西大瑶山地区主要金矿床（点）的成矿前景作出了评估。     

核电饼类锻件制坯过程鐓粗工艺的有限元分析

利用DEFORM软件,对核电锻件制坯过程中的平板鐓粗工艺进行了有限元模拟。分析了在鐓粗过程中,随着压下量的增加,毛坯难变形区的变化;给出了在变形过程中,不同压下量下毛坯内部的变形过程及应力、应变分布情况。通过有限元分析,对解决核电饼类锻件常出现的裂纹和超声波探伤超标等质量问题,提供了有益的参考。     

Set methods of left-turn waiting zone at signalized intersection

To maximize the number of vehicles passing by the stop-line in a cycle and improve the operation efficiency of intersection in China,the settlement of left-turn lane waiting-zone is becoming prevailing. Based on conflicting-point method,the internal mechanism of left-turn flow after stopping line was analyzed through taking postposition left-turn lane waiting-zone intersection for instance. The relationship between the first left-turn vehicle and the last vehicle of previous phase passing the conflicting point was expounded. According to the time of successive arriving of two vehicle flows at conflicting-point,the reasonable layout for waiting area of left-turn vehicles was researched when the clearance index was less than 0. The results suggest that the appropriate layout for waiting area of left-turning vehicles can improve the operation efficiency of intersections.     

Comprehensive assessment on dynamic roof instability under fractured rock mass conditions in the excavation disturbed zone

The damage process of fractured rock mass showed that the fracture in rocks induced roof collapse in Yangchangwan Coal Mine,China.The rock mass was particularly weak and fractured.There occurred 6 large-scale dynamical roof falls in the excavation disturbed zone (EDZ) with the collapsing volume of 216 m3.First,the field detailed geological environment,regional seismic dy-namics,and dynamic instability of roadways were generally investigated.Second,the field multiple-index monitoring measurements for detecting the deep delamination of the roof,convergence deformation,bolt-cable load,acoustic emission (AE) characteristic pa-rameters,total AE events,AE energy-releasing rate,rock mass fracture,and damage were arranged.Finally,according to the time-space-strength relations,a quantitative assessment of the influence of rock-mass damage on the dynamic roof instability was accomplished.     

Relation between structural evolution of the Longmenshan orogenic zone and sedimentation of its foreland basin

In order to determine the area for oil and gas exploration in China's north Sichuan basin, we have divided the time during which the Longmenshan foreland basin was formed into five periods, based on the sedimentary response relationship of the fore-land basin to structural evolution: 1) a late Triassic Noric period; 2) an early-Middle Jurassic period; 3) a late Jurassic to early Cre-taceous period; 4) a late Cretaceous to Paleogene-Neogene period and 5) the Quaternary period. As well, we analyzed the sedimen-tary environment and lithologic features of every basin-forming period. The results show that there are several favorable source-reservoir-cap assemblages in our study area, making it a major region for future oil and gas exploration in China's northern Sichuan basin.     

江西浒坑钨矿含矿韧性剪切带及其^40Ar-^39Ar年代学约束

江西省浒坑钨矿是一个大型石英脉黑钨矿矿床,含矿石英脉除了块状石英脉以外,还大量发育条带状石英脉。本文针对条带状石英脉进行了专门研究,认为条带状石英脉实质上是韧性剪切带,以透入性发育的剪切面理和拉伸线理、剪切透镜体、剪切分异条带普遍发育为特色。剪切带岩石以石英质糜棱岩为主,具有丰富的塑性变形显微构造特征。显微剪切指向构造统计表明,东西向和北西向脉组的运动方式均以左旋正滑为主,近水平脉组则以正滑为主。北西向韧性剪切带的新生绢云母^40Ar-^39Ar坪年龄为140．3±1．0Ma,相应的等时线年龄为139．6±2．4Ma;而东西向韧性剪切带绢云母^40Ar-^39Ar坪年龄则比较复杂,高温阶段年龄可能受到成矿期白云母残斑的影响,中温阶段的表观年龄和总气体年龄更接近前一样品的坪年龄。据此认为韧性剪切变形的年龄为140Ma左右,韧性变形发生在成岩和成矿之后。条带状石英脉系块状石英脉韧性剪切改造而成,推测其形成主要与晚期补充岩体的斜向上侵作用有关,但更为合理的模式需要更多资料的进一步证实。     

细集料对沥青混合料体积和高温特性的影响

通过2种细集料(天然砂、机制砂)、2种级配(AC-13、Sup-12.5)沥青混合料的试验研究,分析了细集料类型和禁区对混合料体积指标和高温动稳定度的影响,结果表明机制砂更能有效提高混合料的高温性能,禁区的存在可有效限制细集料特别是天然砂的用量,以明显提高沥青混合料重载作用下混合料的动稳定度。而体积参数结果表明,Superpave设计方法中用固定空隙率4%标准来确定最佳沥青用量的方法是否合理有待进一步验证。