单量子阱线的Raman谱

利用显微Ｒａｍａｎ谱测量了Ｖ型槽量子阱线,观察和指认了来自单根量子阱线的Ｒａｍａｎ谱,它们是位于２２３和２４３ｃｍ的无序激活峰,位于２６７ｃｍ的量子阱线的ＧａＡｓ限制纵光学模,以及位于４８８和７０７ｃｍ的无序激活峰的二阶和频和三阶组合Ｒａｍａｎ峰。     

三类恰当有效解集在正锥下的等价性和存在性

证明了Ge恰当有效解、Be恰当有效解和He恰当有效解在正锥下的等价性,且在此基础上,由在非空紧凸集上似凸多目标最优化问题的Ge恰当有效解的存在性,得出Be恰当有效解、He恰当有效解的存在性.     

偶64～68Ge同位素的对相变及其演化

应用唯象核芯加两准粒子模型的一种微观实现(sdIBM-2 2q．P．)方案并考虑到实验单粒子能量,较成功地再现了偶^64-68Ge核的基态带、β带、γ带和部分高自旋态能谱．基于唯象模型和微观方案求出了s玻色子不拆对和一个d玻色子发生拆对顺排所需要的最小能量值．该阈值明确指认：随着中子数的增加,偶Ge同位素可能发生从^54Ge核的两准质子顺排态向^68Ge核的两准中子顺排态的演化;揭示了偶Ge同位素对相变对象转移的演化过程．     

半绝缘GaAs光电导天线辐射THz电磁波展宽特性分析

介绍了自洽式多粒子蒙特卡罗方法模拟半绝缘GaAs光电导天线辐射THz电磁时域波形。模型中采用光能、脉宽可调飞秒激光器作为触发光源,模拟的THz电磁波形与实验基本吻合。通过载流子在光电导体内的动态输运特性,分析了辐射THz电磁波场比触发光脉冲展宽的物理机制在于:光生载流子在外电场作用下,从初始状态到速度达到稳态要经历一个动量和能量弛豫过程,而正是由于载流子动量和能量的弛豫过程导致光电导天线辐射的太赫兹波展宽。高光能、低偏置电场下,空间电荷电场是造成光电导天线辐射的THz波呈现双极性的主要原因。     

镶嵌结构锗纳米晶电输运的研究

利用离子注入然后退火的方法制备了镶嵌有锗纳米晶的二氧化硅复合薄膜,从拉曼散射和透射电镜测量了解到薄膜中镶嵌有5~7nm大小的锗纳米晶层.研究了锗纳米晶层在常温和低温下的电输运性质.结果表明:锗纳米晶在100K~300K温度范围内符合莫特变程跳跃电导(VRH)导电,100K以下的低温电导基本上是一常数,导电主要是电子在相邻纳米晶之间的直接跃迁;经退火可消除离子注入引入的缺陷,能增加薄膜的电导;对由3×1017cm-2注量锗离子注入制备的薄膜观察到半导体向金属导电的转变.     

有限势垒量子阱中极化子结合能的压力效应

计入流体静压力效应,同时考虑量子阱中三类光学声子模(局域类体光学声子、半空间类体光学声子和界面光学声子模)对单电子基态能量的影响,采用变分法讨论GaAs/AlxGa1-xAs量子阱中自由极化子的结合能.得到了压力下三类光学声子模对极化子结合能影响随阱宽的变化关系.结果表明:极化子结合能随外加压力增加.     

Photoinduced effects in amorphous semiconductor Ge(S, Se)2 chalcogenide films

The blue shift of optical transmittance edges were observed in amorphous semiconductor Ge(S, Se)2 chalcogenide films with light illumination. The shift in well-annealed films could be recovered by annealing the films near the glass-transition temperature again. The photocrystallization was also observed in amorphous Ge(S,Se)2 films with light illumination by the transmitting electron microscope measurement. The photoinduced phenomina of the amorphous Ge(S,Se)2 films could be applied to designing some new kinds of optical storage materials.     

浅析稻农的共同音乐语汇——以长江流域田歌为例

中国是一个以农业为主的国家,长江流域的稻农主要以稻作为主要劳作方式,年复一年,形成了共同的音乐表现形式——田歌。在长江流域各个省的《中国民间歌曲集成》中,田歌的末尾音调存在大量的下行小三度音调;对长江流域田歌所反映的稻农相似的生产方式和田歌所记录的稻农的情感进行分析,发现其内在联系,提出相同的业缘可能存在共同音乐语汇之拙见。对进一步研究田歌,探究民歌音乐文化内涵具有重要的理论价值和现实意义。     

A 5.3-GHz 32-bit accumulator designed for direct digital frequency synthesizer

A 32-bit pipeline accumulator with carry ripple topology is implemented for direct digital frequency synthesizer.To increase the throughout while hold down the area and power consumption,a method to reduce the number of the pre-skewing registers is proposed.The number is reduced to 29% of a conventional pipeline accumulator.The propagation delay versus bias current of the adder circuit with different size transistors is investigated.We analyze the delay by employing the open circuit time constant method.Compared to the simulation results,the maximum error is less than 8%.A method to optimum the design of the adder based on the propagation delay is discussed.The clock traces for the 32-bit adder are heavily loaded,as there are 40 registers being connected to them.Moreover,the differential clock traces,which are much longer than the critical length,should be treated as transmission lines.Thus a clock distribution method and a termination scheme are proposed to get high quality and low skew clock signals.A multiple-type termination scheme is proposed to match the transmission line impedance.The 32-bit accumulator was measured to work functionally at 5.3 GHz.     

论汉晋宫怨文学情感主题的建构

司马相如《长门赋》、班婕妤《怨歌行》《自悼赋》以及左贵嫔《离思赋》四篇汉晋宫怨诗赋,向人们昭示了古代宫廷女性,尤其是宫妃几难避免的生命悲剧。四篇诗赋在古代宫怨文学的建构中提供了经典的范式,形成望幸、忧宠、自悼、思亲四个情感主题,在中国宫怨文学情感与主题史上起到了不容忽视的奠基作用和导向意义。