基于法切比影响的反铲液压挖掘机的稳定性研究

在对某液压挖掘机整机前倾稳定性系数计算过程中,得出法切阻力比λ的变化对挖掘机稳定性有很大影响。为提高挖掘机整机稳定性,减小整机失稳的概率,保证挖掘机正常工作,提出了在法切阻力比变化情况下追求最大稳定性的挖掘机机构优化方法。综合考虑挖掘机的两种受法切阻力比λ变化影响的典型工况,采用遗传算法,编制Visual Basic软件,对反铲液压挖掘机配重参数进行多目标优化。优化得到的结果提高了挖掘机各工况的稳定性,表明了此种方法的有效性和可行性。     

吉林省农业节能减排--玉米秸秆的能源化利用

吉林省农作物秸秆资源丰富，自“十一五”规划以来，吉林省贯彻执行节能减排方针，特别是在秸秆资源的利用方面取得显著地效果，本文阐述玉米秸秆能源化利用的现状和存在问题，通过秸秆规模化、能源化利用促进吉林省可再生能源的利用，减少秸秆燃烧、减少污染物排放对空气的污染。     

浅析我国采煤技术现状与发展趋势

随着我国社会经济的不断发展,人们对于煤炭资源的需求量也日益扩大,因此高效和高产的采煤成为我国采煤产业发展的必然趋势。为了更快地适应这一趋势的发展,提高煤矿的开采率以保证煤炭资源的供给量能够满足人们的需求,各方纷纷加强对高效和高产采煤技术的研究。本文将通过对我国采煤技术现状和存在问题的浅析,从事实角度出发,展望采煤技术的发展趋势,以期为我国采煤技术的发展提供一定程度的参考。     

连采机掘锚一体化快速掘进施工工艺研究

随着高产高效矿井成为我国矿井建设新的发展方向,巷道尤其是煤巷的掘进速度成为了矿井高产高效生产的一个制约因素。而连续采煤机作为一种新型的巷道掘进设备,具有巷道掘进速度快、成型好、掘进工艺简单、设备故障率低等优点,对于煤层赋存简单的矿井将会大大提高其掘进速度。本文针对河曲磁窑沟煤矿的地质条件,探讨该矿掘进、支护工艺参数的合理取值。     

薪火——“华南系”建筑教师谈学与教

正华南理工大学建筑学院建筑系的教师集体有着丰富的学缘构成,有超过60%来自国内外的各个高校。其中曾经在本校本科或者研究生阶段就读的"华南系"教师也占据了近70%的比例,他们是从1990年代至今,在华南地区经济高速发展的年代保证建筑系师资的重要来源。华南系教师,由于其教育背景,他们的所学、所思、所以为教对学院教育特色及历史传承起着至为关键的影响,是学院目前的骨干力量。     

彩膜不良研磨成功率的分析与研究

彩膜基板伴随行业发展,正在向高PPI和窄边框方向发展,产品的成品率直接影响企业的价值回收。一般来讲,彩膜工艺伴随产生的缺陷,主要的修补手段就是研磨,研磨的成功率直接决定修补对于成品率的贡献程度。研究了与研磨成功率相关的因素,并且寻找到了有效的方法,达到最优化的结果,并且展望未来的新技术。     

兵器装备腐蚀试验研究

兵器装备因其种类繁杂、用途特殊、结构复杂、元器件多,且每种零部件所用材质不同并经不同的防腐处理,如果处理方法或工艺流程安排不当则会影响装备的防腐水平与质量:(1)在制造过程中经     

有关企业差异化营销策略的探讨

从卖方市场到买方市场的转变,使得企业差异化营销策略显得越来越重要.本文探讨了差异化营销的产生背景及其含义,差异化营销的几种策略,并对企业如何科学有效的运用差异化营销策略进行了阐述.     

淮河上游全新世黄土及沉积成因

The dust source and transporting system are two indispensable aspects in the process of loess-palaeosol accumulation. It has been proved that the dust of the Loess Pla-teau mainly comes from the northwestern inland gobi and desert, transported by the East Asia monsoon systems and westerlies. However, there are little researches with respect to the dust source and deposition dynamics of the upper reaches of the Huaihe River. In the present study, we investigated and collected the YPC section with high resolution in the upper reaches of the Huaihe River. The chronological frame was reconstructed by optically stimu-lated luminescence(OSL)dating and correlated with the published loess time series. By comparison of the magnetic susceptibility(MS)and grain size(GS)of loess-soil profile among YPC profile, XJN profile(western Loess Plateau)and the JYC profile(southern Loess Pla-teau), we find sirnilar climate change and pedogenic process between the upper reaches of the Huaihe River and the Loess Plateau, both experienced an extreme dry and the weakest pedogenesis during the last glacial, followed by a transitional episodes from the cold-dry last glacial to the warm-humid mid-Holocene and increased pedogenesis in the early Holocene,then a most humid-warm and strong pedogenesis in the mid-Holocene, and climate deterio-ration and decreased pedogenesis occurred during the late Holocene. But the MS of loess-soil profile sequences in the upper reaches of the Huaihe River was much lower than those in the Loess Plateau, and the GS was much coarser than those in the Loess Plateau.Comparison of GS for these three profiles revealed that there were different dust sources,which belonged to different aeolian transporting systems. The loess in the upper reaches of the Huaihe River was a wind blown deposition of near source, while the coarser dust mainly came from loose alluvial deposits of alluvial and proluvial fans of the Yellow River. The yield-ing and carrying dynamics of the dust in the Huaihe River is the northeast wind prevails in the winter half year.     

IA方案治疗急性髓系白血病四例

目的 探讨IA方案治疗急性髓系白血病(AML)的疗效及安全性.方法 对2009年8月至2010年4月采用去甲氧柔红霉素(IDA)联合阿糖胞苷(Ara-C)的IA方案治疗的4例AML患者的临床资料进行回顾分析.结果 4例患者经IA方案治疗后达持续缓解.结论 IA方案适用于初发、缓解后AML的治疗,可作为首选方案,安全性较好.