例析渐近线问题的三种处理策略

中学数学的许多函数图像和曲线都与渐近线密切相关,如反比例函数、指数函数、对数函数、三角函数、分式函数、双勾函数及几类简单的超越函数等的图像都与渐近线有着千丝万缕的联系,在这些函数的图像中渐近线的定位作用可谓举足轻重．但由于许多同学在学习过程中不能深刻领会“渐近线”的内涵,忽略“渐近线”的现象频频发生,从而导致在综合应用知识的过程中出现偏差．本文就函数图像的渐近线问题提出三种处理方法,以此唤起师生的高度重视．     

Possible Odderon exchange in pp and ■p elastic collisions at the TOTEM experiment

Based on the Froissart-Martin theorem,the Regge theory and the possible Odderon exchange,the total cross-sectionσtot and the ratio of the real to imaginary parts of the forward scattering amplitude p in the pp and pp elastic collisions in the TOTEM energy region are studied in the FPO model.We consider the contributions of the Froissart bound and of the Pomeron,Reggeon and Odderon exchange terms in the scattering amplitude of the pp and pp elastic collisions.Using the Odderon interceptαo(0)=0.5,our theoretical predictions are in good agreement with the recent results of the TOTEM experiment.These results show that the Odderon,corresponding to the odd elastic scattering amplitude,is likely to exist.     

奇异介子光生反应的低能QCD Lagrange量描述

从低能QCD Lagrange量出发, 利用重子夸克结构的［SU_SF(6)O(3)]_sym. SU_c(3)波函数,研究了在核子上的奇异介子光生反应. 计算了γ+p→K ⁺+Λ反应的总截面、微分截面和p-极化. 结果表明: 与传统的唯象的强子理论相比, 仅有一个自由参数(即强相互作用耦合常数)的QCD理论成功地描述了反应过程, 很好地解释了实验结果.     

电子信息专业教学如何培养学生的实用技能

在电子信息专业教学中,要在加强专业理论知识教学的同时,注重电子信息实用技能的培养,培养具有较高的电子信息理论知识和较强的实用技能的专业技术人才,使学生走上工作岗位顺利将电子信息知识和技能应用到实际工作中去。     

构造“可行域” 例析范围题

"可行域"是指线性规划问题中目标函数z=f(x,y)的自变量x和y的取值区域.线性规划问题在近几年高考中备受青睐,题型从当初的简单、平常到如今的综合、创新,已经不断走向成熟.尤其值得关注的是一些难度较大的综合题,在方法上实现新突破,往往依赖于线性规划的相关知识的正迁移,通过构造"可行域",从而使问题的求解变得柳暗花明.笔者研究近年各省市的高考(模)试题,选择几道范围题赏析"利用可行域"的新解法,权作抛砖引玉.     

Synthesis and characterizations of boron and nitrogen co-doped high pressure and high temperature large single-crystal diamonds with increased mobility

We synthesized and investigated the boron-doped and boron/nitrogen co-doped large single-crystal diamonds grown under high pressure and high temperature (HPHT) conditions (5.9 GPa and 1290℃). The optical and electrical properties and surface characterization of the synthetic diamonds were observed and studied. Incorporation of nitrogen significantly changed the growth trace on surface of boron-containing diamonds. X-ray photoelectron spectroscopy (XPS) measurements showed good evident that nitrogen atoms successfully incorporate into the boron-rich diamond lattice and bond with carbon atoms. Raman spectra showed differences on the as-grown surfaces and interior between boron-doped and boron/nitrogen co-doped diamonds. Fourier transform infrared spectroscopy (FTIR) measurements indicated that the nitrogen incorporation significantly decreases the boron acceptor concentration in diamonds. Hall measurements at room temperature showed that the carriers concentration of the co-doped diamonds decreases, and the mobility increases obviously. The highest hole mobility of sample BNDD-1 reached 980 cm²·V^-1·s^-1, possible reasons were discussed in the paper.     

辣根过氧化酶在纳米金／氧化锌球腔微电极阵列上的直接电化学研究

利用Langmuir - Blodgett技术和溶胶-凝胶(sol -gel)法在氧化铟锡(ITO)电极表面制备了有序的纳米金／氧化锌(nano-Au/ZnO)球腔阵列,并采用扫描电镜表征了nano-Au/ZnO球腔阵列的形貌.该阵列的循环伏安曲线具有微电极特性.将辣根过氧化酶(HRP)直接固定于nano-Au/ZnO...     

Vacuum condensates of QCD

We study the properties of QCD vacuum state in this paper. The     

在QCD中核子的静态性质

基于参数化的完全穿衣服的夸克传播子,　利用量子色动力学（QCD）研究了核子的磁矩和电荷半径平方的平均值与夸克动量的依赖关系。预言的核子磁矩和电荷半径的数值与文献中广泛应用的经验值和其他许多具有QCD特征的理论模型所预言的值一致。结果说明了核子的磁矩和电荷半径不是人们通常所理解的一个不变的常数,　而是依赖于核子中夸克动量的一个跑动量,　对于不同动量它们的值是不同的。计算结果也清楚地表明了所采用的参数化的夸克传播子的适用性和可靠性。     

Structure of Nonlocal Vacuum Condensate of Quarks

The Dyson-Schwinger formalism is used to derive a fully dressed quark propagator. By use of the derived form of the quark propagator, the structure of non-local quark vacuum condensate is studied, and the values of local quark vacuum condensate as well as quark gluon mixed condensate are calculated. The theoretical predictions are in good agreement with the empirical one used commonly in the literature.