丁二烯装置的安全生产

丁二烯是生产顺丁橡胶的主要原料,它作为液化气的一种组成成分,具有闪点低、引燃能量小、爆炸下限低、爆炸范围大等特点,因此做好丁二烯在储运、生产过程中的安全生产工作至关重要.     

赛汉塔拉凹陷滑塌浊积岩的发现与勘探意义

通过研究二连盆地赛汉塔拉凹陷中洼槽陡坡带的含鲕粒块状细砂岩从岩性特征、沉积结构及构造特征、粒度特征、测井曲线特征、地震反射特征以及对其形成机理的分析,认为赛83x含油砂岩体为在半深湖一深湖环境形成的滑塌浊积扇沉积.这种类型的滑塌浊积扇具备分选、磨圆度、物性较好等条件,尤其是此类砂岩体往往被形成于深湖一半深湖相还原环境的深灰色、灰黑色泥岩--成熟烃源岩所包围,易形成岩性圈闭,有利于油气的运移和聚集成藏,是断陷湖盆陡坡带油气勘探的重要目标.     

不同粒度松散煤体的氧扩散特性实验研究

以自行研制的煤对氧扩散特性测试装置为实验手段,在常温环境条件下测试了不同粒度松散煤体对氧的自由扩散特性.实验结果表明:煤样粒度的变化对取气腔氧浓度流出曲线的影响表现出2个极限值,煤样粒度在20～100目之间时,取气腔氧气浓度梯度随煤样粒度的增大而增大;当煤样粒度<20目或>100目时,煤样粒度的再变化对氧浓度流出曲线的影响则微乎其微;取气腔氧浓度曲线流形基本符合指数曲线的变化规律.     

单片机自控系统在NS0631型轨道起重机上的应用

单片机自控系统在大型工程机械中得到了越来越广泛的使用，从而使设备的安全性、可靠性大为提高。文章着重分析了NS0631型轨道起重机中自控系统的结构、使用中存在的问题，提出了解决的方法及今后的改进设想。     

Monte Carlo Simulations of High-Performance Implant Free In0.3Ga 0.7As Nano-MOSFETs for Low-Power CMOS Applications

The potential performance of implant free heterostructure In_0.3Ga_0.7As channel MOSFETs with gate lengths of 30, 20, and 15 nm is investigated using state-of-the-art Monte Carlo (MC) device simulations. The simulations are carefully calibrated against the electron mobility and sheet density measured on fabricated III-V MOSFET structures with a high-kappa dielectric. The MC simulations show that the 30 nm gate length implant free MOSFET can deliver a drive current of 2174 muA/mum at 0.7 V supply voltage. The drive current increases to 2542 muA/mum in the 20 nm gate length device, saturating at 2535 muA/mum in the 15 nm gate length one. When quantum confinement corrections are included into MC simulations, they have a negligible effect on the drive current in the 30 and 20 nm gate length transistors but lower the 15 nm gate length device drive current at 0.7 V supply voltage by 10%. When compared to equivalent Si based MOSFETs, the implant free heterostructure MOSFETs can deliver a very high performance at low supply voltage, making them suitable for low-power high-performance CMOS applications     

Microstructure and fatigue characteristics of direct chill cast and electromagnetic cast 2024 Al alloy ingots

The distinct advantages of the electromagnetic casting (EMC) process consist in the presence of stirring motions in the melt, which lead to significant grain size reduction in solidified ingot. Furthermore, surface and subsurface qualities are improved due to the absence of ingot mold. However, it is impossible to achieve the aforementioned advantages in conventional direct chill casting (DCC). In order to contrast the before and after heat treatments of the microstructural and mechanical characteristics of EMC and DCC 2024 aluminium alloys, optical microscopy, scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffractions (XRD), differential scanning calorimetry (DSC), etc. were carried out. Compared with the DCC ingot, the EMC ingot has better mechanical properties not only in the ascast condition but also in the as-aged condition. The DSC curves show that the EMC specimens have high enthalpy, i.e., the thermal kinetic energy to form precipitates during the aging treatment process. Despite heat treatments applied to the DCC ingot, it fails to attain the same mechanical properties as the EMC ingot. Moreover, considering the expernsive scalping operation for DCC ingots, the EMC technique, which offers a lower manufacturing cost, is one of the best manufacturing methods used in obtaining the ingots of wrought aluminum alloys.     

光学薄膜在光通信中的应用

主要介绍了光学薄膜在光通信的无源型器件中的原理及应用,并与光纤光栅和平面光波导型的无源器件作简单比较。     

EPON媒体接入控制的关键技术研究

文章简要介绍了基于以及太网的无源光网络（EPON）这种新型的接入网技术，将其与基于ATM技术的无源光网络（APON）的优缺点进行了比较，并对其媒体接入控制（MAC）的关键技术测距及上行接入进行了讨论，初步提出了光网络单元（ONU）的软、硬件实现方案。     

一种嵌入式TCP／IP的实现

针对许多小型嵌入式系统要求结构紧凑、开销小的TCP／IP协议栈的需求，提出一种可移植的非路由器TCP／IP原型的实现。该TCP／IP原型基于某种小型嵌入式系统，依据RFC1122兼容性规定，提供IP、ARP、TCP、UDP服务和Berkeley Socket编程接口。该实现代码短小，开销低，性能能够满足多数应用需求，具有较强的可移植性。     

76 mm口径EFP成形过程数值模拟及影响因素研究

采用LS-DYNA3D对76mm口径药型罩爆炸成型弹丸(EFP)的成形过程进行了数值模拟，模拟结果与实验数据基本吻合．通过数值模拟着重分析了装药长径比L／D、壳体厚度、药型罩壁厚对EFP速度的影响规律，得到了有关EFP成形速度公式，得出EFP速度随L／D的增大而增大，随药型罩厚度增大而减小，受装药外壳厚度影响不大．