An Optimization Method For Estimating Phase Compositions And Amounts In Two—Phase Nickel Base Superalloys

根据已知镍基合金成分和γ′相成分，运用分层宽容多目标优化法，分别计算了γ相成分及γ′相含量．优化测算过程的实现是通过建立使杠杆定律等式两端数值差最小和两相共格错配度最小的目标函数，并通过设置γ′相含量和基体相成分取值范围的约束条件而实现的．验证了该方法的可行性和准确性．     

Influence of the stress,strain, and temperature on the surface roughness of an AlSl 52100 steel due to an orthogonal cut

In recent years, the finite element method (FEM) has become the main tool for simulating the metal cutting process because research based on trial and error is time consuming and requires high investment. Early studies were done by different investigators. In this research AISI 52100, hardened steel (62 HRC) was selected for an orthogonal machining process as well as metal cutting simulation using the software DEFORM-2D. This software is based on a forging process and has been adapted to an orthogonal machining process. The results of simulated cutting forces were compared with experimental cutting force data to validate the orthogonal cut simulation. Also, the surface roughness was measured, and the influence of the stress, strain, and temperature on the surface roughness was studied.     

Influence of process parameters on thermal-rate treatment of ZA42 alloy

Sand casting process and directional solidification technique combining thermal-rate treatment(TRT) were used. The influence of process parameters on TRT was investigated according to the values of impact toughness. At the same time, the mechanism of TRT was discussed. The results showed that TRT can improve the impact toughness of this alloy, while the hardness is basically constant. The time of heat preservation should not be more than 5min. Different forms of cooling intensification additive have different effects among which the zinc ingot solidified in graphite mold is the best one that can improve impact toughness of samples by more than 80%. With increasing the cooling temperature, the value of α(Al) crystal lattice constant increases. The element Sb has negative effect on TRT.     

4-methoxy-2,6-bis(3,5-dimethylpyrazoyl)-1,3,5-triazine modified carbon paste electrode for trace Cu(Ⅱ) determination by differential pulse volt-ammetry

A differential pulse voltammetric method was developed for the sensitive and selective determination of Cu(Ⅱ) at 4-methoxy-2,6-bis(3,5-dimethylpyrazoyl)-l,3,5-triazine modified carbon paste electrode in 0.05 mol/L KHC8H4O4 solution (pH = 4.02). The oxidation peak of Cu(Ⅱ) was observed at 0.065 V(vs Ag/AgCl) by scanning the potential in positive direc-tion. The analysis procedure consisted of an open circuit accumulation step in stirred sample solution. It was followed by medium exchange to a clean solution and subsequently an anodic potential scan was affected to obtain the voltammetric peak. The current was proportional to the concentration of the Cu(Ⅱ) ion in a range of 1× 10-7-1×10-4 mol/L for 6 min accumulation; the most of metal ions did not interfere with the determination. The developed method was applied to Cu(Ⅱ) determination in coal-ash sample, the results agreed with that of atomic adsorption spectroscopy(AAS).     

Cu-Al-Be形状记忆合金的应力腐蚀性能

用恒载荷法和慢应变速率法及SEM研究了Cu-Al-Be形 状记忆合金在甘油、海水和氨介质中的应力腐蚀性能.结果表明，Cu-Al-Be合金具有良 好的抗海水应力腐蚀性能和较低的氨介质应力腐蚀倾向.单相马氏体有较 好的耐海水腐蚀能力，可减少腐蚀引起的裂纹源；外应力下马氏体的孪晶变形和变体间的界 面迁移，则有利于松弛应力集中，阻碍和延缓腐蚀裂纹源的扩展，从而提高Cu-Al-Be合金的 应力腐蚀能力.     

Determination of heavy metals and volatile aromatic compounds in used engine oils and sludges

Assessment of contaminant releases during utilization of used oils is essential for the determination of environmental acceptability. These paper reports the results of the study examining a toxic metal leachability from used engine oil and sludge samples employing leaching test (TCLP). The leaching test indicated that lead in oil samples exceeded 5-ppm concentration level what qualified them as a toxic waste. The samples of contaminated sludge were found to contain high concentration of total lead, barium and chromium, but the leaching test showed concentration below regulatory limit. The total content of benzene, ethylbenzene, toluene, and xylenes (BETX), and naphthalene in used oil and sludge samples was also determined and was found not to be a significant factor to contamination.     

Gas—Liquid Mass Transfer Coefficient in Stirred Tank Reactors

Volumetric gas—liquid mass transfer coefficient (k_La) data available in the literature for larger tanks (T = 0.39 m to 2.7 m) have been analyzed on the basis of relative dispersion parameter, N/N_cd. It was observed that at a given superficial gas velocity (V_G), k_La values were approximately the same irrespective of geometric configuration (size of the tank, type and size of the impellers, type of the sparger, etc.) at a particular N/N_cd. A single correlation based on N/N_cd is presented which shows satisfactory agreement with the k_La data of different workers.     

Diffusion of additives and plasticizers in poly(vinyl chloride): 4. A programmed temperature technique for the determination of the diffusion parameters of three dialkylphthalates

A programmed temperature technique has been developed for the measurement of the self-diffusion coefficients of additives in polymers. This has been applied to the diffusion of three dialkylphthalate plasticizers in poly(vinyl chloride). Values of the self-diffusion coefficients and the calculated activation energies obtained in this way have been compared with values previously obtained from measurements at constant temperature. It has been shown that the programmed temperature technique gives a very rapid method for the estimation of the activation energy of self-diffusion.     

稳定态二氧化氯杀菌剂的制备及应用

稳定态二氧化氯(C1O2)是一新型杀菌消毒剂，具有高效、广谱、安全的特性，适用范围广，不产生对人体有害物质。介绍了稳定态ClO2的性质、检测、制备条件及其在有关领域的应用。     

旋风管内气相的湍流运动特性

利用二维激光多普勒测速仪(LDV)测量了旋风管内湍流运动的时均速度、脉动速度、能谱函数、微分尺度及湍流耗散等参数，对湍流特性参数分布进行了详细的描述，并初步分析了旋风管内湍流运动特性对颗粒分离的影响.