N-月桂酰肌氨酸钠及其复配物的缓蚀性能

    用电化学方法研究了N-月桂酰肌氨酸钠及其与钼酸钠、甲基苯骈三氮唑和硫酸锌复配对R235钢在自来水中的缓蚀性能,结果表明：N-月桂酰肌氨酸钠在自来水介质中属阳极型缓蚀剂,它与甲基苯骈三氮唑复配、与硫酸锌复配均比单独使用效果好,有较好的协同缓蚀增效作用;但它与钼酸钠复配的缓蚀性能不如单独使用没有协同缓蚀增效作用.     

钨酸钠及其复配缓蚀剂在模拟海水中对碳钢的缓蚀性能

目的考察在模拟海水中,钨酸钠及其与月桂酰肌氨酸钠复配物对Q235钢的缓蚀性能。方法进行挂片失重法实验,研究缓蚀剂添加量对缓蚀效率的影响;测定电化学极化曲线及阻抗谱,对比单一钨酸钠缓蚀剂与复配缓蚀剂的缓蚀效率以及相关拟合数据。结果钨酸钠单独使用时的缓蚀效果良好,缓蚀效率随着添加量的增加而增大,且在碳钢表面的吸附符合修正了的Langmuir吸附模型;与月桂酰肌氨酸钠复配后,缓蚀效率更高,阴极、阳极的塔菲尔斜率均减小,腐蚀电流密度也降低了很多。结论钨酸钠与月桂酰肌氨酸钠复配后比单独使用效果更好,二者有较好的协同缓蚀增效作用;复配缓蚀剂为混合型缓蚀剂。     

海水中水溶性壳聚糖及其降解产物对低碳钢缓蚀性能的影响

利用过氧化氢氧化降解水溶性壳聚糖得到不同分子量梯度的产物,通过端基法测定了产物的数均分子量.在海水体系中,用失重法测定了不同浓度水溶性壳聚糖及其降解产物对低碳钢的缓蚀效率,并用电化学方法和椭圆偏振法分析其缓蚀机理.结果表明:过氧化氢用量的增加有利于降解产物分子量的降低;不同分子量水溶性壳聚糖降解产物浓度为400 mg/L时缓蚀效率最高,且分子量减小有利于缓蚀效率的提高,可达到64.35%;极化曲线实验所得规律与失重实验相符,表明水溶性壳聚糖及其降解产物为阴极型缓蚀剂;椭圆偏振法分析表明,水溶性壳聚糖为多层吸附,且随着分子量的减小,吸附层厚度增厚,缓蚀效率提高.     

用于含聚合物钻井液的缓蚀剂研究

    通过线性极化法筛选出单组分缓蚀效果较好的钼酸钠、含硅化合物为复配的基本配方.利用极化曲线法评定复合缓蚀剂的缓蚀效果,并研究其缓蚀机理.结果表明,复配后的缓蚀效果优于未添加缓蚀剂或添加单组分缓蚀剂,说明复合缓蚀剂各组分之间具有一定的协同缓蚀效果,能够有效地在金属表面形成具有互补性的保护膜,能有效提高自腐蚀电位,降低腐蚀电流.用交流阻抗法分析了缓蚀剂的缓蚀机理,并用重量法进行了验证.     

海水淡化一级反渗透产水中带锈碳钢的腐蚀控制

带锈层碳钢在海水淡化一级反渗透产水中腐蚀非常严重,采用失重法、电化学测量及表面分析技术研究了六偏磷酸钠及硫酸锌复配缓蚀剂对带锈碳钢的缓蚀作用。结果表明,六偏磷酸钠及硫酸锌对带锈碳钢具有很强的协调缓蚀效果,复配药剂的缓蚀效率随着加药量的增加而提高,两者的最优配比为1∶1;综合考虑加药的经济性及缓蚀效果,理想加药量可选择为20mg/L,此时缓蚀率可达70%以上。表面分析结果表明,该复配缓蚀剂能够与碳钢表面氧化物结合成膜,使锈层更致密,从而阻碍腐蚀的进行。     

羧甲基壳聚糖对海水中X70管线钢的缓蚀效果

采用电化学试验、扫描电子显微镜、XRD和FTIR等技术研究了羧甲基壳聚糖及其复配缓蚀剂对海水中碳钢的缓蚀效果。结果表明:羧甲基壳聚糖的缓蚀率随着其质量浓度的升高而升高,当质量浓度为5g/L时缓蚀率达到43.4%,质量浓度继续升高,缓蚀率增大不显著;添加钨酸钠后的复配缓蚀剂使腐蚀速率进一步降低,缓蚀率达57.4%;FTIR、SEM和XRD测试表明羧甲基壳聚糖可吸附在金属表面,形成致密的保护膜。     

羟丙基壳聚糖及其复配的缓蚀性

合成了具有良好水溶性的羟丙基壳聚糖(HPCS),采用傅立叶红外光谱仪(FTIR)对合成产物进行表征,采用失重法、动电位极化和电化学阻抗技术研究HPCS、十二烷基苯磺酸钠(SDBS)和焦磷酸钠(TSPP)缓蚀剂单体及其复配对Q235钢在1mol·L-1 HCl溶液中的缓蚀性能。结果表明,单独添加HPCS、SDBS、TSPP时缓蚀效率较低;HPCS/SDBS、HPCS/TSPP分别以浓度比100∶70(mg·L-1)和100∶30(mg·L-1)复配,缓蚀效率分别提高到83.30%和82.54%;HPCS、SDBS、TSPP三者复合具有良好的协同缓蚀作用,当以浓度比50∶20∶10(mg·L-1)复配时,缓蚀率达到91.93%,且在60℃时仍维持在62.60%。     

水溶性壳聚糖及其磷酸酯在海水中对碳钢的缓蚀作用

对水溶性壳聚糖进行磷酸酯化改性。采用静态失重实验与电化学测试相结合,研究了水溶性壳聚糖及其磷酸酯对Q235低碳钢在海水中的腐蚀抑制作用,并探讨缓蚀机理。结果表明,水溶性壳聚糖对碳钢具有一定的缓蚀作用,随其浓度的增加缓蚀率升高;壳聚糖磷酸酯在300 mg/L时缓蚀率达到88.71%,高温下仍保持较高的缓蚀效率,且持久保持高效。壳聚糖磷酸酯为抑制阴极型缓蚀剂。     

电化学交流阻抗法研究钨酸盐与BTA的协同缓蚀作用

通过电化学阻抗谱技术和表面分析方法研究了钨酸盐和苯并三氮唑对碳钢的协同缓蚀作用。结果发现 :在 pH =9.0 ,氯离子浓度为 5× 10 -3mol/L的水中 ,钨酸盐和BTA单独用作缓蚀剂对碳钢均有一定的缓蚀作用 ,钨酸盐和BTA具有协同缓蚀作用。提高溶液 pH、降低氯离子浓度有助于增强钨酸盐 BTA复配缓蚀作用。复配缓蚀剂的缓蚀机理为WO2 -4 与BTA分别与Fe3+ 和Fe2 + 发生反应生成稳定的膜覆盖于电极表面     

复配缓蚀剂在石油沉积水中对Q235钢的缓蚀性能

采用极化曲线和交流阻抗谱法研究十二烷基苯磺酸钠(SDBS)缓蚀剂单独使用及与十六烷基三甲基溴化铵(CTAB)复配缓蚀剂在石油沉积水中对储油罐钢Q235的缓蚀性能。实验结果表明:单独使用SDBS缓蚀剂对Q235钢有一定的缓蚀效果;使用SDBS与CTAB复配缓蚀剂时,缓蚀效果明显提高,当两者复配比例为1:1且浓度都为0.5mmol/L时,缓蚀效率最高为91%,复配缓蚀剂具有很好的协同缓蚀效应。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

An Easy Way to Quantify the Adhesion Energy of Nanostructured Cu/X(X=Cr,Ta,Mo,Nb,Zr) Multilayer Films Adherent to Polyimide Substrates

An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.     

High-Speed Friction Stir Welding of SiC_p/Al–Mg–Si–Cu Composite

A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

A STUDY OF TEMPERATURE-DEPENDENT VALENCE BOND STRUCTURE OF TITANIUM

On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is e_c~(2.9907) · (s_c~(0.4980) d_c~(2.4927)) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.     

Structural Optimization of Electromagnetic Swirling Flow in Nozzle of Slab Continuous Casting

During the slab continuous casting process, the flow field of molten steel in the mold plays a decisive role in the quality of the slab. In this paper, electromagnetic swirling flow in nozzle technology is proposed to control the flow field in mold.This technology can drive molten steel to rotate inside the submerged entry nozzle by electromagnetic force, thereby controlling the flow field. This research shows that it can reduce the impact of molten steel on the bottom of nozzle and partly reduce the negative pressure at the upper part of nozzle outlet which is even eliminated by optimizing the structure and angle of nozzle. The area of heat flux of the mold wall becomes larger, and the crest value of heat flux gets lower than that without swirling in nozzle and any nozzle optimization. The meniscus fluctuates smoothly, and the flow velocity at the top surface is within a reasonable range. The temperature field distribution in the mold is uniform which was beneficial to the growth of equiaxed crystal and decreased element segregation.