美、英、日三国高等教育大众化扩张重点之比较和借鉴

本文通过比较和分析美、英、日三国高等教育大众化扩张的重点，归纳得出此三国高等教育大众化扩张重点皆放在非正规普通大学的层次类型上，并认为这一现象对我国高等教育大众化建设很有借鉴意义，我国当前大众化发展的重心应该适当下移，应该以专科层次的高等职业技术教育为重点，走民营化道路。     

复合材料纤维缠绕成型CAD/CAM相关技术研究

纤维缠绕成型是制造高强度复合材料制品的一种重要的工艺方法，将CAD／CAM方法应用其中可以大大提高生产效率，降低设计成本。本文提出了纤维缠绕CAD／CAM系统的总体方案，并对其中缠绕数学模型、线型优化、丝嘴轨迹生成等量要组成部分进行了分析与研究，为CAD／CAM系统的开发奠定了理论基础。     

Effect of friction reclaimed materials of waste brake-shoe on basic performance of mortar

Discarded train brake shoes mainly consist of steel-backed friction material. To be better reutilized, its essential features and its interaction in cement-based material need to be studied. Consequently, particle size analysis, SEM, IR and TGA were used to investigate two types of waste brake shoes, i e, mechanical grinding friction reclaimed material of waste brake-shoe (G-FRMWBS) and pyrolysis-friction reclaimed materials of waste brake-shoe (P-FRMWBS). The latter exhibited less organic content, larger range of particle size distribution and smaller medium particle diameter. Both types contained inorganic particles of spherical and irregular shapes, striped with steel fiber. Upon isometric substituting fine aggregates, G-FRMWBS lifted the strength of mortar effectively that was increased by 16.6% and 17.5% when the replacing rate was 5%; the value went up to 19.2% and 19.2% when the replacing rate was 10%. Moreover, inclusion of FRMWBS enhanced the chloride penetration resistance, and optimized the pore characteristic and ITZ (interfacial transition zone) as well.     

不同引渠形式下深式短管进口泄流能力的试验研究

为研究红岩河水库导流泄洪洞深式短管进口引渠形式由明渠改成涵洞后对其泄洪能力的影响,对其在明渠和涵洞两种形式下分别做水工模型试验,验证其水力特性。结果表明,较明渠形式,涵洞形式下的导流泄洪洞同水位下泄流量有不同程度的减小,下泄流量减小在导流泄洪洞进口为压力流状态时表现明显,且减小值随水位的升高而变大;大坝度汛期100年一遇洪水时,试验下泄流量较设计下泄流量约小6.35%;运行期100年一遇洪水时,试验下泄流量较设计下泄流量约小6.51%;运行期2 000年一遇洪水时,试验下泄流量较设计下泄流量约小6.95%。建议在将红岩河水库导流泄洪洞深式短管进口引渠由明渠改成涵洞形式后,需关注导流泄洪洞的下泄流量减小问题,避免由于水库下泄流量不足引起的大坝安全问题。     

真空增压铸造技术及其应用前景

详细论述了真空增压铸造的技术原理、工艺特性及技术优点。结合铝合金铸件大型、复杂、薄壁、整体化和高气密性的发展趋势，针对性地分析了真空增压铸造技术推广应用的适应性，并提出了相应的技术对策。     

Microstructure and sliding wear behavior of pseudo-alloy PS45/CuAl8 composite coating sprayed by HVAA technique

A pseudo-alloy PS45/CuAl8 composite coating was sprayed on steel substrate by high-velocity activated arc spraying (HVAA) process. Its sliding wear behavior at room temperature was evaluated by M-2000 wear tester. For comparison, a single CuAl8 coating was also prepared and tested under the same conditions. It is found that the pseudo-alloy composite coating consists of α-Cu and γ-Ni metallic matrix phases together with homogenously distributed minor Al 2 O 3 , Cr 2 O 3 oxide phases. Moreover, pseudo-alloy coating possesses much better sliding wear resistance than CuAl8 coating due to the enhanced hardness and microstructural homogenization. Fatigue wear and abrasive wear are responsible for the wear-down mechanism of the pseudo-alloy coating.     

自动铺丝构件缺陷形成机理的研究进展

自动铺丝是一种重要的复合材料自动化成型方法,可实现连续变角度铺放,适合大曲率复杂构件的制造,但成型质量受到了多种工艺参数的影响。本文从自动铺丝预浸料的粘弹性和流动性、结晶度、铺层的层间剪切强度、残余热应力以及最大弯曲力等方面对自动铺丝构件成型缺陷的形成进行了表征和机理分析;给出了影响构件成型缺陷的工艺参数,并总结了工艺参数优化方法的研究进展。最后,对自动铺丝构件成型缺陷形成机理的未来研究方向进行了展望。     

Structure and Photoluminescence of A Blue‐Green‐Emitting Phosphor for Near‐UV White LEDs

A series of phosphors Ca_12(0.97?x)Al₁₄O₃₂F₂: 0.03Ce³⁺, xTb³⁺ have been prepared by a hightemperature solid‐state reaction using boric acid as flux. These oxyfluorides crystallize in cubic structure, space group. Under the near ultraviolet excitation within wavelength range 310–390 nm, Ca_12(0.97?x)Al₁₄O₃₂F₂: 0.03Ce³⁺, xTb³⁺ phosphors exhibit an intense emission covering a broad band of 370–500 nm derived from the 5d→4f transitions of Ce³⁺ and a characteristic emission at 544 nm of Tb³⁺. The emission can be tuned from blue to green by altering the relative ratio of Ce³⁺ to Tb³⁺ in the composition. The energy‐transfer mechanism from Ce³⁺ to Tb³⁺ is investigated based on the site occupancy of the luminescence center in the crystal structure of the Ca₁₂Al₁₄O₃₂F₂ host. More importantly, when a certain amount of boric acid is added as flux in the synthesis, the fluorescence intensity of the phosphors increases about 65%. Because of its broad excitation and efficiently tunable blue to green luminescence, the Ca_12(0.97?x)Al₁₄O₃₂F₂: 0.03Ce³⁺, xTb³⁺ phosphors may find promising application as a near UV‐convertible phosphor for white‐light‐emitting diodes.     

建筑结构动力时程响应分析与计算的新方法

基于状态空间理论分析与计算结构动力时程响应问题,根据结构动力学方程,引入结构系统的状态变量,建立结构动力时程响应分析的状态方程,并给出非齐次状态方程的解。对于求解矩阵指数函数有多种解法,着重介绍了凯莱哈密尔顿法、状态空间迭代法和精细积分法。对结构动力时程响应问题按三种解法分别建立了计算格式,并编制了相应计算程序。给出若干数值算例,其计算结果表明,状态空间法分析计算结构动力时程响应精度好、效率高,是一种非常有效的方法。     

基于开放式控制器的铣削颤振在线抑制

为实现在线抑制铣削颤振,对颤振领域常用的传感器监控技术,尤其是三向切削力和振动加速度传感器的各向分量在颤振监控过程中的时域和频域敏感信号特征进行试验研究。针对监控的颤振敏感信号频域特性,研究快速傅里叶变换技术对信号有效信息的在线提取技术。对自激颤振的机理进行分析,建立颤振频率与主轴转速间的关系模型,为实现变主轴转速抑制自激颤振提供理论基础。对集成在线参数采集、反馈控制的全软件型模块化铣削控制器进行设计,将在线抑制颤振的相关变主轴转速算法嵌入开放式控制器中,并设计控制参数数据流在控制器模块间的实现流程。对连续变切削深度铝合金工件进行在线颤振抑制加工试验,试验验证开放式智能铣削控制器在线抑制颤振相关技术的正确性。