A new way of transformation from a-quartz to coesite

A laboratory method combining the high-energy mechanical ball milling and high static pressure has been suggested for modelling synthesis of coesite in the Earth's crust. A window of milling time, a mechanical collision-induced intermediate phase ofα-quartz and its condition of easily crystallizing into coesite under the condition of 3.0 GPa, 923 K, < 1.0 min have been discovered. The new method needs much shorter synthesizing time and lower synthesizing critical pressure than those used before. The Raman spectra for the coesite synthesized by the present method have covered all the information of those natural and synthesized coesites reported before. It is demonstrated that this method has a great potential in geo-science research and implied the other possible mechanism of coesite formation in the Earth's crust.     

高温闷棚防治西瓜枯萎病研究

该试验研究利用7、8月高温晴热期的自然光热能对大棚西瓜田进行灌水闷棚,经10d后棚内土表至20cm内的土壤全天可维持40℃以上高温.经室内测试,西瓜枯萎病株根内的病菌Fusariumoxysporum在41℃下死亡的时间需4d,在43℃下需1d.田间试验表明,灌水闷棚20d后第一茬连作西瓜枯萎病的防治效果达90～100%,闷棚25d以上,第二茬的防效仍达84.5%以上.     

住宅楼人工挖孔桩的高低应变动力测试探讨

人工挖孔灌注桩是烟台市应用广泛的桩型之一．这种桩具有较高的承戴力，桩-土相互作用情况较预制桩复杂。因此探讨高低应变动力试桩法对这类桩的适宜性问题显得日益重要．本文以某住宅楱为例，探讨了人工挖孔灌注桩高低应变动力测试的原理和仪器设备、测试过程与结果，并对高应变动测中的承栽力确定、动阻力取值等问题进行了分析研究．     

论高等职业教育中的角色转换

高等职业教育在我国蓬勃发展,如何适应高职教育、办好高职教育,学校、教师和学生等多方面的角色转换是关键。角色转换是系统工程,必须从管理规范、机构设置等多方面入手,才能做好角色转换。     

强流加速器束晕控制中填充因子对束粒子密度的影响

运用PIC多粒子模拟程序，采用延迟反馈控制法，研究了离子束在运行过程中粒子分布情况．通过分析比较，得到了对束晕进行有效控制后的粒子分布规律，为强流加速器的应用提供了有用的参考．     

Optimal design study of high order FIR digital filters based on neural network algorithm

An optimal design approach of high order FIR digital filter is developed based on the algorithm of neural networks with cosine basis function . The main idea is to minimize the sum of the square errors between the amplitude response of the desired FIR filter and that of the designed by training the weights of neural networks, then obtains the impulse response of FIR digital filter . The convergence theorem of the neural networks algorithm is presented and proved, and the optimal design method is introduced by designing four kinds of FIR digital filters , i.e., low-pass, high-pass, bandpass , and band-stop FIR digital filter. The results of the amplitude responses show that attenuation in stop-bands is more than 60 dB with no ripple and pulse existing in pass-bands, and cutoff frequency of passband and stop-band is easily controlled precisely .The presented optimal design approach of high order FIR digital filter is significantly effective.     

平稳随机信号准确模型的研究

针对对平稳随机信号建立参数模型的常用信号处理方法，研究了信号建模的本质，给出了“准确模型”的定义，指出，对给定的平稳随机信号，以其不同阶次统计量建立的“准确模型”的输出信号与原信号并不相等，二者只是在相应的统计特征上相匹配。从这一概念出发，在总结了二阶统计意义下建模的一些主要结论后指出，平稳信号在二阶统计意义下总可以准确建模，证明了在三阶统计意义下并非所有的平稳过程均可准确建模，并给出了可准确建模的必要条件。     

Y型冷轧带肋钢筋轧机孔型设计

本文根据连轧的基本原理研究了Ｙ型冷轧带肋钢筋轧机的基本孔型系统及孔型设计方法，经工业生产检验其产品完全达到ＧＢ１３７８８－９２［１］的技术标准     

高浓度煤粉燃烧器实验研究

提出一种新型的煤粉燃烧器——相交式高浓度煤粉燃烧器,半岛可有效地实现高效低污染燃烧.