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管线风险评价是８０年代兴起的热门研究领域，是在全面考虑影响管线失效的内外因素和失效后果的情况下，综合确定各管段的风险程度，为管线用户的维护管理提供依据。详细介绍了风险技术的内容和方法，风险评估的目的和原则，定性风险技术和定量风险技术，为管线的风险技术推荐了一个可供操作的实施过程，诸如先期检验、维护程序、维修更换决策等。同时，还对几种风险技术用于工程评价的不确定性影响因素进行了分析，对基于风险确定事后行动方式进行了讨论，并用一些实例说明了这些技术如何用于工程问题，而这些工程问题包含着不确定性、安全风险、经济损失和环境破坏等。风险工程评价对于不确定性技术经济变量的工程问题具有重要意义。风险技术的优越性还在于可依据一些程序进行操作，加强了许多没有规律性的因素之间的信息交流，这有助于保持管道系统处于适当的安全水平。     

用VC062型聚合管生产尼龙6高粘切片

用VC062型聚合管生产纺制帘子线用尼龙6高粘切片。对设备及工艺进行了改造,提高进料管的物料温度,提高物料在前聚合器的开环速率,增加排水措施,促进VK管中产物分子量的提高。     

对AG50左箱体压铸模浇注系统的改造及工艺分析

叙述了对ＡＧ５０左箱体引进压铸模浇注系统的改造情况并进行了工艺分析,探讨了浇注系统中浇道、内浇口的设计数量及金属液体通过内浇口时,控制导入流向,控制汇流点,设置合理的排溢系统,以达到提高成品率的目的。     

如何充分发挥党员的先锋模范作用

开展"一转双创"是扎实开展"共建美丽幸福油田"活动的助推器。广大党员只有在实践党的宗旨上发挥共产党员的先锋模范作用,在提高专业技能上发挥共产党员的先锋模范作用,在争创一流业绩上发挥共产党员的先锋模范作用,在道德情操上发挥共产党员的先锋模范作用,才能在工作岗位中建功立业,起到中流砥柱和先锋模范作用,为实现企业内涵式发展,共建和谐企业做出贡献。     

大型管式加热炉燃烧传热CFD数值模拟

为了研究大型管式加热炉内部流动、传热和传质情况,采用计算流体力学的方法对石化行业中广泛应用的大型加热炉炉膛内部进行了数值模拟,用标准的k-ε湍流模型描述烟气湍流情况,非绝热的简化PDF燃烧模型计算了燃烧情况,离散坐标辐射传热模型对炉膛内辐射传热状况进行模拟。计算结果和工业运行数据吻合较好,模拟计算结果为大型加热炉优化设计提供了理论指导。     

从我国社会转型看江泽民"三个代表"的思想

改革开放使中国步入社会转型的历史快车道,显示了社会转型时期经济知识化,政治民主化和思想文化多元化的重要特征。江泽民三个代表的思想为我们党在社会转型时期如何加强自身的建设提供了创造性的思想对策,具有重大理论意义和深远的现实意义。     

液压电梯的单片机控制系统的设计与研究

介绍速度反馈式液压电梯的单片机控制系统。描述系统的组成和软件设计技术。该系统具有自动采集液压电梯轿厢运行数据、控制电梯运行过程、显示运行和调试参数及输出运行曲线等功能，并配置数据库。实用结果表明：这种单片机控制系统具有较优的动、静态控制性能、温度稳定性和较强的抗干扰能力。也非常适合于流体动力控制这一类系统使用。     

Calculation of the Detonation Velocities and Detonation Pressures of Dinitrobiuret (DNB) and Diaminotetrazolium Nitrate (HDAT‐NO3)

The enthalpies of combustion (Δ_combH) of dinitrobiuret (DNB) and diaminotetrazolium nitrate (HDAT‐NO₃) were determined experimentally using oxygen bomb calorimetry: Δ_combH(DNB)=5195±200 kJ kg⁻¹, Δ_combH(HDAT‐NO₃)=7900±300 kJ kg⁻¹. The standard enthalpies of formation (Δ_fH°) of DNB and HDAT‐NO₃ were obtained on the basis of quantum chemical computations at the electron‐correlated ab initio MP2 (second order Møller‐Plesset perturbation theory) level of theory using a correlation consistent double‐zeta basis set (cc‐pVTZ): Δ_fH°(DNB)=−353 kJ mol⁻¹, −1 829 kJ kg⁻¹; Δ_fH°(HDAT‐NO₃)=+254 kJ mol⁻¹, +1 558 kJ kg⁻¹. The detonation velocities (D) and detonation pressures (P) of DNB and HDAT‐NO₃ were calculated using the empirical equations by Kamlet and Jacobs: D(DNB)=8.66 mm μs⁻¹, P(DNB)=33.9 GPa, D(HDAT‐NO₃)=8.77 mm μs⁻¹, P(HDAT‐NO₃)=33.3 GPa.     

Hydrogen diffusivity enhancement in alumina pellets due to impregnated palladium

Single-pellet moment technique was used for the evaluation of effective diffusivities and adsorption equilibrium constants of hydrogen, carbon dioxide, and helium in pure alumina and palladium-impregnated alumina pellets. It was found that hydrogen was strongly adsorbed on palladium of Pd-alumina pellets, and significant enhancement of hydrogen diffusivity was observed due to impregnated palladium at 40°C. On the other hand, for carbon dioxide and helium, effective diffusivities obtained in Pd-alumina pellets were smaller than the corresponding values in pure alumina due to higher tortuosity factor values of Pd-alumina pellets.     

PREDICTION OF VELOCITY PROFILES OF SHEAR THINNING FLUIDS FLOWING IN ELASTIC TUBES

Non-Newtonian fluid flow characteristics in inflatable and collapsible elastic tubes are relevant to bio-fluid mechanics and other applications. The radial velocity profiles in an elastic tube during steady laminar flow of a shear thinning aqueous solution of 1.5% carboxy methyl cellulose (CMC) were investigated using ultrasound Doppler velocimetry. The shear rate–dependent viscosities obtained using a rheometer were well represented by the Carreau model. Measured storage and loss moduli indicated the CMC solution to be inelastic up to 2% concentration. The velocity profiles were predicted by integrating the theoretical equation derived by equating the shear stress along the tube radius involving pressure drop to that of the Carreau model using its parameters. The agreement between predicted and measured velocity profiles was good. The predicted pressure drop is about the same as the experimental value at lower flow rates. In contrast, the measured pressure drop is lower than that predicted at higher flow rates due to inflation of the tube. Good agreement between estimation (Hagen-Poiseuille's law) and measurement (tube shape image analysis) for the detection of elastic tube expansion while increasing flow rates is found.