碱熔-蒸馏-ICP-AES法测定载体催化剂中钌

研究了Ru/Al2O3催化剂中钌含量的测定，考察了溶样方法、测定方法、测定条件的影响。选用750℃过氧化钠熔融，以高锰酸钾和铋酸钠蒸馏分离，用电感耦合等离子体原子发射光谱法(ICP-AES)测定样品中钌含量。结果表明，方法测定含量范围0.1%~10%，精密度(RSD)为2.0%~2.5%，加标回收率为96.9% ~102.8%，可满足实际物料中钌含量测定的要求。     

ICP-AES法测定废催化剂不溶渣中的铂、钯和铑

采用碱熔-碲共沉淀分离富集,用电感-耦合等离子体发射光谱法(ICP-AES)测定精细化工废催化剂不溶渣中的铂、钯、铑含量。系统考察了碱熔解和碲共沉淀富集分离的条件,研究了碲富集物中的主要元素和比例,确定了ICP-AES法测定铂、钯、铑的条件。结果表明,碱熔-共沉淀能够充分分离富集样品中的铂、钯、铑;测定催化剂不溶渣中653~3652 g/t铂、447~3804 g/t钯、539~6433g/t铑时,相对标准偏差(RSD)、样品加标回收率分别为铂0.84%~1.78%、97.0%~99.4%,钯1.05%~1.82%、97.0%~100.6%,铑1.00%~2.12%、98.2%~100.4%。方法分析快速、易于掌握,已用于生产分析中。     

氧化除钌-ICP-AES法测定钌化合物中的杂质元素

利用四氧化钌易挥发的特点，将钌溶液用高氯酸冒烟去除钌，用ICP-AES测定样品中杂质元素。对钌基体干扰、高氯酸用量、杂质元素分析谱线、仪器分析参数等进行了研究，确定了最佳实验条件。结果表明，采用高氯酸冒烟，可将试液中钌含量降低至50 μg/mL以下，有效消除钌对杂质元素的光谱干扰。方法具有较宽的测定范围，对三氯化钌样品中20个杂质元素测定的相对标准偏差(RSD，n=9)为2.0%~3.5%，加标回收率在86.3%~118.0%之间，可满足钌化合物中杂质元素的测定要求。     

湿法消解-ICP-AES内标法测定铑派克废料中的铑

建立了硝酸-硫酸-高氯酸分解样品、钇内标电感耦合等离子体发射光谱法(ICP-AES)测定铑派克废料中的铑含量的方法。对样品处理方法、湿法消解条件、测定精密度和再现性、方法准确度进行了研究。称取铑派克废料约0.6 g,用9 mL硝酸、0.5 mL硫酸和1 mL高氯酸,在200℃加热消解除去有机物,盐酸溶解残渣,ICP-AES测定样品中100~1500 g/t的铑,相对标准偏差(RSD,n=9)为0.41%~1.35%,加标回收率99.1%~99.7%,满足生产测定的要求。     

王水不溶渣的碱性加压氧化溶解及其钌含量的测定

建立了一种以次氯酸钠作氧化剂,碱性加压氧化法溶解王水不溶渣中钌的方法。以酒精沉淀,盐酸溶解,硫脲分光光度法进行样品中钌含量的测定。方法对王水不溶渣中钌的溶解效果好,操作简单;王水不溶渣加压氧化浸出液共存的主要杂质离子Na⁺、Cl^-、Pb²⁺、Bi²⁺等(不含Os)对吸光度无影响。采用硫脲分光光度法测定样品中13.771 μg/mL钌,RSD (n=6)为1.536%,加标回收率为98.73%~102.76%。     

ICP-AES测定等离子熔炼合金中的铂、钯和铑

建立了一种以碱熔-碲共沉淀分离、电感耦合等离子体发射光谱(ICP-AES)测定等离子熔炼合金样品中铂、钯和铑含量的方法。研究了样品处理和测定条件。结果表明,样品与过氧化钠混匀,在730℃马弗炉中保温25 min后,熔融物可用稀盐酸完全浸出;在盐酸介质中,加入碲溶液和二氯化锡溶液微沸30 min,所得铂、钯和铑共沉淀充分;在选定条件下,对铂、钯和铑含量为0.5~7.0、2.0~40.2和0.2~7.0 g/kg的样品,测定相对标准偏差(RSD)分别为0.44%~1.52%、0.58%~1.06%和0.61%~1.98%,加标回收率分别为99.4%~101%、99.1%~100.5%和98.3%~101%。     

密闭消解-重量法测定掺铱、锇和钌的黄金饰品中金量

掺杂铱、锇和钌的黄金饰品中金的量难于用密度法或X射线荧光光谱法(XRF)测定。将样品在高压密闭条件下经过王水消解后,掺杂的难溶金属可过滤分离,以80%水合肼(用水稀释6倍)作还原剂,将滤液中的金还原成沉淀,以重量法测定金含量,金粒的纯度用火花原子发射光谱法测定。方法加标回收率为96.2%~101.6%,相对标准偏差(RSD,n=6)为0.09%~0.23%,可满足掺杂铱、锇和钌的黄金饰品中金的测定。     

ICP-AES法测定三氯化钌中铁、铜、钙和镁的量

建立了电感耦合等离子体发射光谱法测定三氯化钌中杂质元素含量的分析方法。通过优化仪器条件,选择合适的测定谱线、扣除背景测定样品中的杂质元素,各待测元素的精密度(RSD)为6.00%~16.4%,加标回收率为90.00%~110.0%。方法能满足三氯化钌产品中杂质元素的分析要求。     

脉冲红外和热导检测法测定钌粉和钌靶中氧、氮含量

建立了钌粉和钌靶中氧、氮含量的测定方法。研究了样品前处理、仪器条件、助熔剂选择、方法准确度和精密度等。以锡-碳作助熔剂,在选定条件下,采用脉冲红外和热导检测法,测定50×10^-6氧时RSD<10%,测定40×10^-6氮时RSD<25%;加标回收率:氧100%~102%,氮91%~101%。测定范围:氧0.002%~0.4%,氮0.0001%~0.02%。方法简便、快速、精密度和准确度满足质量控制要求。     

共沉淀分离富集-ICP-AES法测定铜灰渣中金、铂、钯

建立了碲共沉淀分离富集、电感耦合等离子体原子发射光谱法(ICP-AES)测定铜灰渣样品中微量元素金、铂、钯的方法。研究了影响测量的各种因素,确定了最佳测定条件。方法的检出限为:Au 5.6μg/L、Pd 8.2μg/L、Pt 3.6μg/L,回收率93.2%~102%,相对标准偏差(RSD)为:1.21%(Au)~3.45%(Pd),方法测定结果与火试金法一致。方法准确、简便快速,易于掌握。     

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.