微波水解衍生高效液相色谱法测定饲料中的氨基酸

建立了一种微波水解衍生高效液相色谱同时测定饲料中17种氨基酸含量的方法。采用2,4-二硝基氯苯作为柱前衍生试剂,利用C_(18)色谱柱分离。二极管阵列检测器进行检测,检测波长为360 nm,并对微波水解时间及温度进行优化。17种氨基酸在2.5~50 mg/L范围内呈良好线性关系,相关系数为0.990 7~0.999 9;相对标准偏差为0.88%~4.2%;加标回收率为90.6%~107.2%;检出限为0.15~2.37 mg/L。研究结果表明,150℃下微波水解16 min的结果与传统加热水解(110℃,24 h)的效果基本相同。该方法分析时间较短,灵敏度较高,可用于饲料中氨基酸含量的检测。     

光纤放大器受激布里渊散射效应抑制

提出了一种多波长窄线宽光纤放大器,其种子光由多个单频激光耦合而成,所有单频激光波长几乎相等（波长间隔小于1 nm）,频率间隔大于两倍布里渊频移。建立了此类多波长窄线宽光纤放大器的完整理论模型,分析了放大器中受激布里渊散射（SBS）与种子数目的关系。搭建了双波长和三波长窄线宽光纤放大器,进行SBS阈值输出功率测定实验。实验结果与理论模拟结果基本一致,验证了理论模型的合理性;双波长和三波长放大可以有效抑制SBS效应,大幅提高放大器输出功率。     

单模光纤激光极限功率的数值研究

对光纤激光极限功率的探索和其受限因素的分析, 有利于为大功率光纤激光器的发展提供理论依据和实验指导. 本文考虑热效应、光效应、非线性效应和抽运亮度等因素对光纤激光极限功率的影响, 分析了掺镱和掺铥光纤的极限功率和受限因素. 在此基础上, 结合激光在光纤中单模传输的条件, 计算了单模掺镱和掺铥光纤激光的极限功率. 计算结果表明, 在现有技术条件下, 使用常规的976 nm和793 nm激光二极管抽运, 单模掺镱和掺铥光纤激光的极限功率分别为4.2 kW和7.8 kW, 其中单模掺铥光纤激光的功率水平还远低于它的极限功率的原因是受抽运亮度的限制. 最后分析指出减小纤芯的数值孔径和改进少模光束的光束质量是提升单模光纤激光极限功率的重要途径.     

致密砂岩气藏应力敏感的全模拟试验研究

高温高压全模拟全直径致密砂岩气藏岩石降压开采试验数据揭示了致密砂岩气藏高速开采可对储层造成渗透率损害 ,损害的机理是孔隙介质中微粒迁移堵塞孔喉和高速开采所导致有效上覆压力增加使孔喉缩小所造成的综合效应。微粒迁移可通过提高生产压差解决 ,而防止大压差生产所引起的应力敏感则必须严格控制生产压差在 0 .2～ 8MPa范围内 ;,对渗透率低于 0 .2× 1 0 - 3μm2 的储层则可适当放大生产压差     

钆对Mg-2Al-1Zn合金高温力学性能的影响

研究了Gd的添加对AZ21基体合金高温（200℃）力学性能和抗蠕变性能的影响。结果表明：AZ21-xGd合金由-αMg和Al2Gd两相组成,中间相Al2Gd使合金高温拉伸性能和抗蠕变性能得到显著提高,但降低了合金的延伸率。在Gd添加量为2%（质量分数）时,200℃下合金的抗拉强度和屈服强度分别达到148和90 MPa,但随着Gd含量的增加,高温拉伸强度有所下降;当Gd添加量为3.5%时,在200℃/50MPa蠕变条件下,合金70 h的蠕变量为1.2%,第二阶段蠕变率比AZ21基体合金下降了1个数量级。晶界上的Al2Gd中间相数量逐渐增多是提高合金的抗蠕变性能的主要原因,但在晶界上过多的Al2Gd中间相不利于提高合金的高温强度。     

低压VDMOSFET的设计与研制

对击穿电压为60 V,导通电阻为10 mΩ VDMOSFET进行了优化设计.给出了外延层电阻率,外延层厚度,单胞尺寸等的优化设计方法和具体值.提出了多晶硅场板结构的终端理论和终端设计,使该器件既满足指标要求又能最低限度的降低成本.     

Effects of Inertia on Evolutionary Prisoner's Dilemma Game

Considering the inertia of individuals in real life,we propose a modified Fermi updating rule,where the inertia of players is introduced into evolutionary prisoner's dilemma game(PDG) on square lattices.We mainly focus on how the inertia affects the cooperative behavior of the system.Interestingly,we find that the cooperation level has a nonmonotonic dependence on the inertia:with small inertia,cooperators will soon be invaded by defectors;with large inertia,players are unwilling to change their strategies and the cooperation level remains the same as the initial state;while a moderate inertia can induce the highest cooperation level.Moreover,effects of environmental noise and individual inertia are studied.Our work may be helpful in understanding the emergence and persistence of cooperation in nature and society.     

祁连山北缘老君庙冲断带构造几何学特征及演化

基于老君庙构造带三维地震资料, 结合以往研究成果, 分析祁连山北缘西段老君庙带的构造几何特征及构造演化。得到以下认识: 老君庙冲断带具有双层结构, 包括浅部的三角剪切型褶皱-冲断构造以及冲断带层下盘隐伏的逆冲构造楔体; 该冲断带自东向西与北东?南西走向的 134 断裂链接, 形成统一的“134-老君庙弯曲断裂”体系, 其后缘为134 走滑兼逆冲性质的调节断裂, 前锋为庙北三角剪切型褶皱-冲断系; “134-老君庙-青头山”断裂围限的上盘逆冲岩片向前陆方向扩张, 导致平行冲断带近东西向的挤压调节变形, 引起浅部新生代地层发生近南北走向的褶皱变形。     

Analysis of the Chinese air route network as a complex network

The air route network, which supports all the flight activities of the civil aviation, is the most fundamental infrastructure of air traffic management system. In this paper, we study the Chinese air route network (CARN) within the framework of complex networks. We find that CARN is a geographical network possessing exponential degree distribution, low clustering coefficient, large shortest path length and exponential spatial distance distribution that is obviously different from that of the Chinese airport network (CAN). Besides, via investigating the flight data from 2002 to 2010, we demonstrate that the topology structure of CARN is homogeneous, howbeit the distribution of flight flow on CARN is rather heterogeneous. In addition, the traffic on CARN keeps growing in an exponential form and the increasing speed of west China is remarkably larger than that of east China. Our work will be helpful to better understand Chinese air traffic systems.