D���数字功率放大器电路失真分析及其负反馈方案讨论

于2010-11-23批量导入

D-木糖异构酶基因亚克隆及其序列分析

我们大肠杆菌K12的D-木糖操纵子中克隆了D-木糖异构酶基因，并以Bal31缩短DNA方法，获得了彼此相差约200bp的亚克隆。而后，用质粒系统直接测定了这些亚克隆片段的基因序列，并进一步得出含有D-木糖异构酶基因的1620bp全序列。序列结果表明，其结构基因长为1320bp，编码着由440个氨基酸组成的蛋白，与Lawlis和Schellerberg发表的D-木糖异构酶基因序列相比，同源性达99.8%。

Relationship between load/unload response ratio and damage variable and its application

The physics-based parameter: load/unload response ratio (LURR) was proposed to measure the proximity of a strong earthquake, which achieved good results in earthquake prediction. As LURR can be used to describe the damage degree of the focal media qualitatively, there must be a relationship between LURR and damage variable (D) which describes damaged materials quantitatively in damage mechanics. Hence, based on damage mechanics and LURR theory, taking Weibull distribution as the probability distribution function, the relationship between LURR and D is set up and analyzed. This relationship directs LURR applied in damage analysis of materials quantitatively from being qualitative earlier, which not only provides the LURR method with a more solid basis in physics, but may also give a new approach to the damage evaluation of big scale structures and prediction of engineering catastrophic failure. Copyright (c) 2009 John Wiley & Sons, Ltd.

Relationship between load/unload response ratio and damage variable and its application

The physics-based parameter: load/unload response ratio (LURR) was proposed to measure the proximity of a strong earthquake, which achieved good results in earthquake prediction. As LURR can be used to describe the damage degree of the focal media qualitatively, there must be a relationship between LURR and damage variable (D) which describes damaged materials quantitatively in damage mechanics. Hence, based on damage mechanics and LURR theory, taking Weibull distribution as the probability distribution function, the relationship between LURR and D is set up and analyzed. This relationship directs LURR applied in damage analysis of materials quantitatively from being qualitative earlier, which not only provides the LURR method with a more solid basis in physics, but may also give a new approach to the damage evaluation of big scale structures and prediction of engineering catastrophic failure. Copyright (c) 2009 John Wiley & Sons, Ltd.

加速器高频D���路Q值的计算与测量

介绍了回旋加速器高频单D���盒D���路Q值的计算与测量方法。重点对Q值的理论计算进行推导,并对计算原理进行说明。然后对计算结果和测量结果进行比较。得出的计算和测量结果基本吻合。误差产生的主要原因是计算过程中的近似和短路片接触电阻的取值,其中短路片接触电阻是一个重要因素,在设计腔体时应引起足够的重视。

关于量化和A/D-D/A的讨论

数字、量化、量化效应、模拟、模拟量、A/D���换、D/A转换是计算机控制工程和控制理论上的常见概念。静心推敲,发现有不少流行性的误解。例如:不是“量化”而是截尾或四舍五入,不是“数字量”而是bit量,不是“模拟量”而是物理量等。

Tree-ring-derived precipitation records from inner Mongolia；China；since a.d. 1627

IEECAS SKLLQG

Tree-ringbased drought reconstruction (a.d. 1855-2001) for the Qilian mountains；northwestern China

IEECAS SKLLQG

Compound specific D/H ratios and molecular distributions of higher plant leaf waxes as novel pale oenvironmental indicators in the Chinese Loess Plateau

IEECAS SKLLQG

HIRFLSFC高频D���压测量

介绍了用韧致辐射能谱测量高频 D���压方法及测量结果。此方法的优点在于不受高频频率、主磁场及分布参数的影响

低能氘离子束轰击固体靶产生的远程D-D���聚变现象研究

利用强流低能氘离子束轰击由吸氢金属形成的氘自吸收靶，研究固体内Ｄ－Ｄ聚变反应规律。并通过对实验测得的Ｄ－Ｄ聚变伴随粒子能谱，探索Ｄ－Ｄ聚变反应与靶材料结构的相关性。同时，利用氘团族离子（ｄ３＋）和氘核（ｄ＋）来轰击吸氘固体，研究固体内Ｄ－Ｄ聚变反应的特性。实验中观测到了伴随离子能谱中介于质子峰（３ＭｅＶ）和氚峰（１ＭｅＶ）之间的一个宽峰。结果分析表明。该峰是由固体靶内超出离子射程几倍至十几倍处发生的Ｄ－Ｄ聚变反应出射的质子所形成。同时还发现独立氘核产生的这种深部Ｄ－Ｄ核聚变的反应率高于速度相同的氘团簇离子中的氘核的反应率。