Observation of robust edge superconductivity in Fe(Se,Te) under strong magnetic perturbation

The iron-chalcogenide high temperature superconductor Fe(Se,Te) (FST) has been reported to exhibit complex magnetic ordering and nontrivial band topology which ...     

高容量温盘驱动器伺服码同步时钟录写技术

提出了可变频时钟写入方法和锁相环倍频时钟写入方法，给出了这两种写入法的读／写电路，并分析了其性能。结果证明，可变频时钟写入方法电路简单，刻写时钟周期短；锁相环倍频时钟写入过程较前者长，但其频率范围容易调整。两者均适合高密度小型温盘的时钟录写。     

单一颗粒流分形模型及有效热导率计算

首次提出了颗粒流中粒子的分形模型，得到粒子在不同分维下的分形分布，并和麦克斯韦分布进行比较，分析了两种分布产生差异的物理机制．在此基础上研究了单一颗粒流的有效热导率，得到其解析表达式，并分析了有效热导率随粒子温度、粒子分维的变化规律．     

Inactivation of the apoptosis effector Apaf-1 in malignant melanoma

Metastatic melanoma is a deadly cancer that fails to respond to conventional chemotherapy and is poorly understood at the molecular level. p53 mutations often occur in aggressive and chemoresistant cancers but are rarely observed in melanoma. Here we show that metastatic melanomas often lose Apaf-1, a cell-death effector that acts with cytochrome c and caspase-9 to mediate p53-dependent apoptosis. Loss of Apaf-1 expression is accompanied by allelic loss in metastatic melanomas, but can be recovered in melanoma cell lines by treatment with the methylation inhibitor 5-aza-2'-deoxycytidine (5aza2dC). Apaf-1-negative melanomas are invariably chemoresistant and are unable to execute a typical apoptotic programme in response to p53 activation. Restoring physiological levels of Apaf-1 through gene transfer or 5aza2dC treatment markedly enhances chemosensitivity and rescues the apoptotic defects associated with Apaf-1 loss. We conclude that Apaf-1 is inactivated in metastatic melanomas, which leads to defects in the execution of apoptotic cell death. Apaf-1 loss may contribute to the low frequency of p53 mutations observed in this highly chemoresistant tumour type.     

带哨嘴喷嘴射流流场的离散涡模拟

采用离散涡方法模拟了两种不同形状哨嘴的喷嘴出口流场旋涡结构和压力分布。模拟结果表明 ,射流在喷嘴出口和哨嘴出口形成的旋涡结构在流场及其他涡元的作用下 ,向下游运动 ,在流场中某个地方形成低压区 ,这有助于诱发空化现象。对两种不同喷嘴的出口流场进行比较发现 ,哨嘴形状对形成的射流流场的旋涡结构有很大影响。因此 ,研究和应用空化射流必须考虑喷嘴出口哨嘴形状的影响     

Dynamic Analysis of Cable Roofs Under Transient Wind:A Comparison Between Time Domain and Frequency Domain Approaches

At present, high-speed computing capabilities and advanced nonlinear dynamic finite element procedures enable detailed dynamic analysis of cable structures. Although deterministic approaches require considerable analysis time and effort in relation to modeling, running, and data processing, they seem to be the only alternative to obtain high accuracy. Detailed dynamic analysis of cable roof networks is sophisticated and requires advanced modeling expertise. This paper presents a comparison between detailed nonlinear dynamic analysis and a simplified frequency domain approach to estimate the maximum probable response of weakly nonlinear cable roofs. The approach can be considered as alternative to detailed time-domain analysis in the preliminary design phase, or can be used to validate results obtained from more elaborated numerical models. The proposed method is illustrated with two examples of cable net roofs that were also analysed in the time domain.     

The p53 tumour suppressor gene

The cell cycle is composed of a series of steps which can be negatively or positively regulated by various factors. Chief among the negative regulators is the p53 protein. Alteration or inactivation of p53 by mutation, or by its interactions with oncogene products of DNA tumour viruses, can lead to cancer. These mutations seem to be the most common genetic change in human cancers.     

多尺度自适应加权形态边缘检测方法

针对常用的多尺度边缘检测方法因卷积运算造成模糊图像边缘，提出一种多尺度自适应加权形态边缘检测方法，利用大小不同的结构元素提取图像边缘特征，在大尺度下抑制噪声，可靠地识别边缘，在小尺度下定位，再由粗到细跟踪边缘，得到边缘的位置，再由各尺度结构元的抗噪性确定加权值的大小，然后加权处理得到最后的边缘结果，实验表明，用多尺度自适应加权形态边缘检测算法可得到较理想的图像边缘。     

1,1-二甲基肼还原Np(V)的动力学研究

采用分光光度法,对硝酸体系中1,1-二甲基肼还原Np(Ⅴ)的动力学进行了研究,求出了反应的动力学方程.实验结果表明:提高1,1-二甲基肼浓度、增加酸度、升高温度均有利于加快反应速率,离子强度对反应速率的影响很小.     

Wavelet fractal character of overlapping signal

A new method based on the combining of the wavelet theory with the fractal theory and named wavelet fractal peak position method (WFPPM) is introduced to extract the number of the components and the relevant peak positions from overlapping signals in chemistry .The overlapping signal is first transformed into continuous wavelet transform value of time domain in certain dilation range via continuous wavelet transform (CWT),and then changed into capacity dimensions (Dc),The number of the components and the relevant positions of overlapping peaks can be identified easily according to the change of Dc.An investigation concerning the influence of different dilation ranges on the peak positions extracted by WFPPM is also provided .Studies show that the WFPPM is an efficient tool for extracting the peak positions and identifying the number of peaks from unresoloved signals,even when this kind of overlapping is significantly serious,Relative errors of lless than 1.0% in peak positions are found when WFPPM is used in the processing of the cadmium (Ⅱ)-indium(Ⅲ) mixture system .The analytical results demonstrate that the desired peak positions can be extracted conveniently ,accurately and rapidly from an unresoled signal via WFPPM,Tremendous developing and applications based on currently reported WFPPM in extracting overlapping signals would be expected in the near future.