江西民俗文化旅游产品深度开发研究

民俗文化旅游作为文化旅游的重要分支,具有独特的民族性、地域性、历史性和文化性,越来越受到游客的青睐.江西民俗文化旅游资源丰富,有吸引无数中外游客的古越人悬棺葬习俗、赣南客家风情、国家非物质文化遗产江西赣傩等,但民俗文化旅游发展却处于初级阶段.民俗文化旅游开发中存在文化内涵挖掘不深、特色不够鲜明、旅游基础设施不完善等问题.对此,本文针对性地提出了深度挖掘民俗文化内涵、深度开发民俗文化旅游产品以及精心设计旅游线路等深度开发的策略.     

Flaking and degradation of polyurethane coatings after 2 years of outdoor exposure in Lhasa

The exposure of a high gloss polyurethane aircraft topcoat system with polyurethane intermediate coating and epoxy primer to strong ultraviolet radiation in Lhasa, Tibet was studied by using scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflectance Fourier-transform infrared (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS). Micro-flakes were found to form on the topcoat surface after exposure and the size and quantity of the flakes increased with the increase of the exposure time. The magnitude of micro-bulges and the topcoat roughness increased after a long exposure to sunlight. Flakes and micro-bulges resulted in the loss of the topcoat gloss. ATR-FTIR and XPS analysis indicated that chain scissions of the polyurea C==O group and the polyurethane C―O―C and CO―NH groups occurred, and the degradation products of NH and carbonyl groups formed due to the exposure. The breaking of the chemical structure of the polyurethane resulted in a decrease in its elasticity and in the adhesion of the flakes to its surface.     

Aluminum matrix composites reinforced by molybdenum-coated carbon nanotubes

To extend the application of carbon nanotubes (CNTs) and explore novel aluminum matrix composites, CNTs were coated by molybdenum layers using metal organic chemical vapor deposition, and then Mo-coated CNT (Mo-CNT)/Al composites were prepared by the combination processes of powder mixing and spark plasma sintering. The influences of powder mixing and Mo-CNT content on the mechanical properties and electrical conductivity of the composites were investigated. The results show that magnetic stirring is better than mechanical milling for mixing the Mo-CNTs and Al powders. The electrical conductivity of the composites decreases with increasing Mo-CNT content. When the Mo-CNT content is 0.5wt%, the tensile strength and hardness of Mo-CNT/Al reach their maximum values. The tensile strength of 0.5wt% Mo-CNT/Al increases by 29.9%, while the electrical conductivity only decreases by 7.1%, relative to sintered pure Al. The phase analysis of Mo-CNT/Al composites reveals that there is no formation of Al carbide in the composites.     

Fabrication and thermal conductivity of copper matrix composites reinforced by tungsten-coated carbon nanotubes

Carbon nanotubes (CNTs) were coated by tungsten using metal organic chemical vapor deposition. Magnetic stirring was employed to disperse the W-coated CNTs (W-CNTs) in a Cu matrix, and then, the mixed powders were consolidated by spark plasma sintering. The W-CNTs obtained a uniform dispersion within the Cu matrix when the W-CNT content was less than 5.0vol%, but high content of W-CNTs (10vol%) resulted in the presence of clusters. The W-CNT/Cu composites containing low content of W-CNTs (<5.0vol%) exhibited a higher thermal conductivity than the sintered pure Cu, while the CNT/Cu composites exhibited no increase in thermal conductivity after the incorporation of uncoated CNTs. The W-CNT content was found to play a crucial role in determining the thermal conductivity of the W-CNT/Cu composites. The thermal conductivity of the W-CNT/Cu composites increased first and then decreased with the W-CNT content increasing. When the W-CNT content was 2.5vol%, the W-CNT/Cu composite obtained the maximum value of thermal conductivity. The thermal resistance of the (W-CNT)-Cu interface was predicted in terms of Maxwell-Garnett effective medium approximation, and its calculated value was about 3.0×10-9 m2·K·W-1.     

居住区共享停车场运营策略

为缓解城市停车供需不平衡的困境,将居住区内空闲时段的车位共享的停车管理模式引起了广泛关注.然而,在共享车位管理策略的制定方面,对如何避免返回的车位提供者与社会停车用户之间的停车时空冲突问题却重视不足.在总结和考虑车位提供者不同的返回规律的前提下,以停车场内共享车位的共享率和管理者的收益最大化为目标,构建相应的居住区车位共享运营策略的数学优化模型.通过数值实验对构建的模型的有效性进行分析.结果表明:当管理者拒绝用户冲突时,若车位提供者的返回速率与社会停车用户离开速率相近时,变更共享策略时间逐渐趋于稳定;当管理者可接受一定概率用户冲突时,停车场内总车位数量越多,则越需要将变更共享策略时间提前.     

青藏高原盐湖观测站概述

 盐湖长期观测对资源开发和盐湖学基础研究具有重要意义。介绍了青藏高原3个锂硼盐湖科学观测站的建站背景、已有基础设施、观测设备、研究进展及展望。观测站分别建在青藏高原北部3个重点锂硼盐湖区--扎布耶、当雄错和班戈湖。建立至今,已在3个科学站配备了水化学分析、气象、水文自动观测等相关仪器设备,建成蒸发实验平台。依托3个盐湖观测站,开展了重点盐湖系统连续气象、水文动态变化观测、盐湖型锂硼矿床动态变化研究、盐湖矿物资源提取实验等工作。下一步,需对科学站所积累的大量气象、水文资料进行整理,力争建立可用性好的数据库,实现数据共享。     

基于RST的混凝土硫酸盐侵蚀评价指标分析及损伤程度预测

为了分析混凝土硫酸盐侵蚀评价指标的重要性,应用粗糙集理论(RST)中的知识约简方法挖掘评价指标.将权重确定问题转化为粗糙集中属性重要性评估问题,建立了关于混凝土硫酸盐侵蚀评价指标重要性的关系数据模型.根据实测结果对各个评价指标的权重进行计算.结果表明,超声波波速和长度变化率的权重系数最大,回弹值次之,质量变化率和侵蚀深度最小.该方法使得混凝土硫酸盐侵蚀评价指标的选取具有客观性,提高了硫酸盐腐蚀程度预测的精度.最后,通过实例证明该方法合理有效,能够预测混凝土硫酸盐侵蚀损伤程度.     

控冷工艺及奥氏体化温度对C92DA钢组织性能的影响

对C92DA帘线钢进行连续冷却转变曲线测定,观测其热处理后的室温相组织和维氏硬度,研究控冷工艺及奥氏体化温度对C92DA钢组织性能的影响。结果表明,使C92DA钢获得最佳组织性能的控冷速率为10℃/s,奥氏体化温度为900℃;C92DA钢珠光体转变温度随冷却速率增大而降低,转变时间随冷却速率增大而缩短;C92DA钢珠光体片层间距随冷却速率增大而减小,片层排列方向趋于紊乱。     

CSP结晶器内钢液流动及凝固的数值模拟

应用数值模拟方法,建立CSP漏斗型结晶器内钢液流动及凝固传热耦合模型。针对结晶器内铸坯角部受到强冷的特点,对结晶器内热流密度采用修正方程进行计算,分析热流密度修正系数对铸坯凝固坯壳表面温度计算精度的影响。通过比较不同拉坯速率下结晶器内钢液凝固的特点,研究凝固坯壳对结晶器内钢液流动行为的影响。结果表明,采用热流密度修正系数后,铸坯凝固坯壳角部温度的计算值与实际情况更相符;提高拉坯速率可使铸坯凝固坯壳厚度减小;拉坯速率较大时凝固坯壳厚度随铸坯距弯月面距离的增大基本呈线性增长,拉坯速率为3m/min时,凝固坯壳在生长过程中厚度的增长有短暂的停滞现象;凝固坯壳对钢液流动的影响较大,主要是由钢液有效流动区域减少及两相区额外动量阻损造成的。     

山区改扩建低等级公路施工期安全保障措施研究

通过对山区改扩建低等级公路施工期道路特征和环境特征的分析,获得交通安全影响因素。在吸收高等级公路施工期保障措施的基础上,针对低等级公路的安全影响因素,归纳出适合山区改扩建低等级道路的常规安全保障措施;将宽容性理念引入施工期安全保障中,从主动引导,降低事故伤害和适度防护的角度去系统的保障低等级公路施工期的安全。