雄激素非依赖前列腺癌细胞系代谢组学的初步研究

探讨雄激素依赖性前列腺癌LNCaP细胞系向雄激素非依赖性前列腺癌细胞系(LNCaP-AI和LNCaP-AI+F)转变过程的代谢组学变化,寻找前列腺癌发生雄激素耐药的可能发生机制.利用超高效液相色谱-四极杆-飞行时间质谱,在电喷雾电离源在正离子模式下,采用60%(V/V)甲醇-0.85%(w/V)NH4HCO3溶液在-4...     

硝基修饰MOF-5材料的制备及催化氨基甲酸酯热分解!

采用直接混合法在室温下制备了含硝基的金属-有机骨架材料MOF-5-NO2,并采用X射线衍射分析,红外光谱,N2等温吸附和扫描电子显微镜对其进行了表征.结果表明,MOF-5-NO2具有与MOF-5相似的晶体结构和表面形貌,二者都具有高比表面积及微孔特性,但由于硝基的吸电子效应,MOF-5-NO2比MOF-5具有更强的Lewis酸性,因而对氨基甲酸酯热分解制备异氰酸酯的反应具有良好的催化活性.在无溶剂条件下,MOF-5-NO2使苯氨基甲酸甲酯热分解的反应速度显著提高,催化剂转化频率达到ZnO的7倍以上;二苯甲烷二氨基甲酸苯酯热分解的中间产物减少,二苯甲烷二异氰酸酯的收率达到81.6%.     

新型喹唑啉类PDE7抑制剂类似物的合成

以邻氨基苯甲酸为原料,经溴代和环合反应合成了4个新型喹唑啉类PDE7抑制剂类似物,其结构经1H NMR和ESI-MS表征。     

透明激光陶瓷散射损耗分析

 为了定量分析激光陶瓷中散射损耗对其透过率的影响,通过建立气孔尺寸分布模型,引入第二相体积比概念,并结合Mie散射、瑞利散射和全散射积分等理论,讨论了激光陶瓷中气孔、晶界第二相和表面粗糙度等引起的散射损耗对激光陶瓷透光性能的影响。研究结果表明：气孔率的大小将明显影响陶瓷透过率,且气孔尺寸分布决定了透过率包络的变化趋势;晶界和表面散射对透过率的影响主要集中在短波长处;在气孔率较低情况下,晶界第二相的存在是导致短波长处透过率急剧降低的主要因素。     

Adaptive and optimal detection of elastic object scattering with single-channel monostatic iterative time reversal

In active sonar operation,the presence of background reverberation and the low signal-to-noise ratio hinder the detection of targets.This paper investigates the application of single-channel monostatic iterative time reversal to mitigate the difficulties by exploiting the resonances of the target.Theoretical analysis indicates that the iterative process will adaptively lead echoes to converge to a narrowband signal corresponding to a scattering object’s dominant resonance mode,thus optimising the return level.The experiments in detection of targets in free field and near a planar interface have been performed.The results illustrate the feasibility of the method.     

高斯光束斜入射法布里-珀罗干涉腔后的反射光强分布

基于多光束干涉原理,推导了高斯光束斜入射法布里-珀罗干涉仪后的反射光强表达式.在此基础之上数值研究了入射角对高斯光束的反射特性的影响.研究结果表明:当法布里-珀罗干涉腔的腔长满足反共振时,随着入射角的增大,反射光的光强分散,峰值强度下降后呈现出幅度衰减的波动;峰值位置随着入射角的增大,呈现出幅度越来越小的振荡偏移;光斑大小随入射角的增大,呈现出幅度减小的振荡.     

A 2.048μm Tm,Ho:GdVO4 Laser Pumped Doubly Resonant Optical Parametric Oscillator Based on Periodically Poled Lithium LiNbO3

A multi-grating periodically poled LiNb03 （PPLN） doubly resonant optical parametric oscillator （DROPO） pumped by a 2-ttm laser is demonstrated experimentally. Employing acousto-optically Q-switched Tm,Ho：GdV04 laser with pump pulse of 25ns and repetition rate of lOkHz as pump sources firstly, the noncritically quasi- phase-matched （QPM） tunable mid-IR output in 3.87-4.43 μm is produced. Wavelength tuning is achieved with crystal temperature tuning from 50-180^o C. When the incident average pump power is 3 W at 2.048μm, the total OPO output power of 195mW at wavelength 3.88μm is obtained, corresponding to optical-to-optical conversion efficiency up to 6.5%.     

STABILITY OF BRIGHT SCREENING-PHOTOVOLTAIC SPATIAL SOLITONS

We present a theoretical analysis of the stability of screening-photovoltaic (SP) spatial solitons in biased photovoltaic-photorefractive materials in the case of neglecting the loss of the material and the effect of diffusion. When an incident optical beam is a SP soliton, this beam propagates along a linear path with its shape kept unchanged. When the maximum amplitude, width and functional form of an incident optical beam are slightly different from those of a SP soliton, the beam reshapes itself and tries to evolve into a solitary wave after a short distance. That is, these SP solitons are stable against small perturbations. However, optical beams that significantly differ from SP soliton solutions tend to experience larger cycles of compression and expansion, and their maximum amplitudes oscillate with propagation distances. The larger the perturbations, the stronger the oscillation.     

强光场中原子的电离速率

以静态场隧道电离为基础,在准静态近似的条件下,对描述强光场中原子及其各阶离子电离的电离速率进行了较为系统的总结,纠正了早期对隧道电离的电离速率公式进行讨论并且后来的计算中被广泛引用的文献「１０」中公式的错误,地部分稀有气体原子及其各了子在线偏振、圆偏振强光场中的了速度及相应的阈值光强进行了比较。     

关于误差方差估计渐近正态收敛速度的上,下界

考虑线性回归模型 Y_■=x_4~′β+e_■ i=1,2,…设误差序列■,i≥1满足条件:e_■ i≥1 i.i.d.,Ee_1=0,Ee_1~2=σ~2>0,∞>Var e_1~2=τ~2>0。记■_n~2=1/(n-r){sum from j=1 to n e■-sum from k=1 to r (sum from j=1 to n a_(akj)■_j)~2} δ(n)=τ~(-2)E(■_1~2-σ~2)~2I_((|■-σ~2|≥■τ)+τ~(-3)n~(1/2)|E(■_1~2-σ~2)~3I_((|■_1~2-σ~2|<(nτ)~(1/2))+τ~(-4)n~(-1)E■_1~2-σ~2)~4I_((|■-σ~2|0使得■|P(■_n~2-σ~2)/(Var■_n~2)~(1/2))≤x)-Φ(x)|≤C(δ(n)+n~(-1/2)) ■|P(■_n~2-σ~2)/(Var■_n~2)~(1/2))≤x)-Φ(x)|+n~(-1/2)≥C_1δ(n)。