水热法法合成Bi4Ti3O12纳米晶

以Bi(NO3)3·5H2O和Ti(OCrH9)4为原料,KOH作为矿化剂,在200℃温度下水热反应24 h获得了纯相Bi4Ti3O12粉体.利用XRD对合成粉体的物相进行了表征,利用TEM和SEM观察了合成粉体颗粒的微观形貌.结果显示,所合成的粉体为片状或带状的单晶Bi4Ti3O12颗粒,片状颗粒的平面与(001)面平行.分析了片状结构Bi4Ti3O12形成的机制.     

铁酸铋粉末的制备及性能研究

研究了以硝酸铋(Bi(NO3)3·5H2O)、硝酸铁(Fe(NO3)3·9H2O)为原料,氢氧化钠(NaOH)做矿化剂,采用水热合成的方法制备的高纯度高结晶度的单相铁酸铋BiFeO3粉末。研究了不同反应温度(150~190℃)和不同反应时间(5~48h)对BiFeO3粉末相结构与微观形貌变化的影响,获得了规律性的结果,温度的提高和适当的反应时间均有助于粉末中杂相的减少,而BiFeO3颗粒的形貌主要受温度的影响,反应时间只对BiFeO3颗粒大小稍有影响。研究结果还表明,制备的高纯度高结晶度的单相BiFeO3粉末具有相对强的磁性。文章对该类多铁性材料的研制开拓了研究思路。     

钙钛矿型铁酸铋粉体的水热合成及表征

分别以FeCl3·6H2O和Fe（NO3）3·9H2O为铁源，Bi（NO3）3·5H2O为铋源，氨水为沉淀剂，KOH为矿化剂，采用共沉淀法制备前驱物，水热合成出纯相的BiFeO3粉体。借助X射线衍射、扫描电镜和傅里叶变换红外光谱分析，对所制备的粉体的晶相结构、显微形貌和键性进行了表征。结果表明，以FeCl3·6H2O为铁源水热制备BiFeO3粉体比以Fe（NO3）3·9H2O为铁源的合成温度更低，温度范围更宽；不同的铁源和前驱物浓度对所制备BiFeO3粉体的显微形貌影响很大；所制备BiFeO3粉体存在Fe-O键的弯曲振动和伸缩振动，表明了FeO6八面体的存在和BiFeO3的钙钛矿结构。     

ZnSe微球在不同水热条件下的制备与表征(英文)

以Zn(NO3)2·6H2O和Na2SeO3作为原料,通过水热法制备ZnSe纳米晶。探讨了水热反应温度、反应时间、NaOH浓度和N2H4·H2O的添加量对最终产物的相组成、显微形貌和颗粒尺寸的影响,并借助XRD、SEM、TEM、PL等测试手段对产物的相组成、显微形貌和颗粒尺寸进行表征。添加20 mL 1 mol/L NaOH溶液和10 mL N2H4·H2O溶液,在180°C的温度下水热反应4 h制备的产物主要是立方闪锌矿结构的ZnSe微球,所得的ZnSe微球从内到外是由平均尺寸约20 nm的ZnSe纳米晶组成。结果表明:较低的水热温度和较短的反应时间都不利于得到结晶好的纯相ZnSe,产物结晶性不好,而且还会产生杂相和有较多缺陷。添加适量浓度的NaOH和水合肼才能确保得到形貌均匀、发光性能好的ZnSe微球。     

反应时间对溶剂热法制备Bi_2Se_3纳米片的影响

以BiCl3和Se粉为原料,二甘醇(DEG)作为溶剂,Na2SO3作为还原剂,碱性条件,在160℃的反应温度下,利用溶剂热法成功地合成Bi2Se3纳米片,并研究不同反应时间(20,22,24h)作用下所得产物结构形貌的变化。利用XRD和SEM对所合成产物的晶相结构及表面形貌进行表征。结果显示:在不同反应时间下所合成的粉体均为纯物相(均为六方晶相)的纳米片状Bi2Se3,且反应22h条件下所得产物形貌为大小均一、分散性良好的六边形片状结构,其厚度为10～50nm。并分析片状结构Bi2Se3的形成机制。     

PZT纳米晶粉体的水热合成及表征

本文选取近于MPB的组成Pb(Zr0.52Ti0.48)O3进行了研究.通过水热法合成了纯相钙钛矿型纳米晶锆钛酸铅(PZT)粉体.所用原料试剂为分析纯Pb(NO3)2、Zr(NO3)4·5H2O、Ti(OC4H9)4,NaOH作为矿化剂.原料试剂按Pb(Zr0.52Ti0.48)O3化学计量比混合放入50 mL内衬聚四氟乙烯的高压釜中,填充度为70%.高压釜在170～270℃之间选择一定温度加热2 h后在冰水中冷却到室温.前躯体及水热处理的粉体通过XRD和SEM进行表征.PZT相在220℃加热2 h开始出现.在270℃加热2 h合成了纯相钙钛矿型纳米晶PZT粉体.粉体的平均尺寸为25 nm.     

Hydrothermal Synthesis of Nano-sized Cupric Tungstate (Ⅵ) Dihydrate and Its Synthesis Mechanism

选用Cu(NO3)2·3H2O和Na2WO4·2H2O分析纯作为反应原材料,通过水热合成法制备了纳米级的Cu WO4·2H2O粉体。讨论了前驱体Cu2WO4(OH)2的生成过程,并且建立了在水热合成过程中前驱体Cu2WO4(OH)2向Cu WO4·2H2O转变的机理。利用HRTEM以及XRD分析了前驱体和水热反应产物的物相及微观结构和形貌。结果表明:水热反应产物Cu WO4·2H2O粉体呈球形,粒径分布范围为20~30 nm。Cu WO4·2H2O粉体的生成过程符合原位结晶机制。在长时间的高热高压的水热环境中,WO42-离子在前驱体Cu2WO4(OH)2表面吸附扩散,通过脱水和原子重排,Cu WO4·2H2O在Cu2WO4(OH)2表面异相形核。WO42-离子通过Cu WO4·2H2O层与Cu2WO4(OH)2发生反应,直到WO42-离子被耗尽。     

水热合成法制备纳米级CuWO_4·2H_2O粉体及其合成机理(英文)

选用Cu(NO3)2·3H2O和Na2WO4·2H2O分析纯作为反应原材料,通过水热合成法制备了纳米级的Cu WO4·2H2O粉体。讨论了前驱体Cu2WO4(OH)2的生成过程,并且建立了在水热合成过程中前驱体Cu2WO4(OH)2向Cu WO4·2H2O转变的机理。利用HRTEM以及XRD分析了前驱体和水热反应产物的物相及微观结构和形貌。结果表明:水热反应产物Cu WO4·2H2O粉体呈球形,粒径分布范围为20~30 nm。Cu WO4·2H2O粉体的生成过程符合原位结晶机制。在长时间的高热高压的水热环境中,WO42-离子在前驱体Cu2WO4(OH)2表面吸附扩散,通过脱水和原子重排,Cu WO4·2H2O在Cu2WO4(OH)2表面异相形核。WO42-离子通过Cu WO4·2H2O层与Cu2WO4(OH)2发生反应,直到WO42-离子被耗尽。     

乙丙醇辅助水热合成K0.5Na0.5NbO3基陶瓷粉体

以Nb2O5、Na OH、KOH和异丙醇(C3H8O)为原料,采用水热法合成K0.5Na0.5Nb O3粉体,研究了C3H8O、Ta、Sb及Sb-Ta共掺杂掺杂对K0.5Na0.5Nb O3粉体的物相、形貌及粒径大小的影响。结果表明:Sb、Ta掺杂使粉体物相由正交相转变到四方相结构;加入C3H8O及Ta掺杂粉体呈立方形貌趋势,Sb及Sb-Ta掺杂粉体具有连生态八面体形貌;C3H8O的加入使得粉体粒径减小,掺杂后粉体粒径大小的关系为:K0.5Na0.5Nb(1-y)SbyO3>K0.5Na0.5Nb1-x-yTaxSbyO3>K0.5Na0.5Nb(1-x)TaxO3。     

熔盐法制备NaNbO_3纳米粉体的研究

以Na2CO3和Nb2O5为反应物,NaCl为熔盐,在800℃温度下熔盐反应4h成功获得了纯钙钛矿结构NaNbO3(NN)纳米粉体。利用XRD对合成粉体的物相进行表征,利用TEM和SEM观察合成粉体颗粒的微观形貌,并与固相法合成的粉体进行比较。结果显示,熔盐法所合成的粉体为无团聚的立方块状的单晶NaNbO3颗粒,其平均尺寸约200nm。NaNbO3形成机制为溶解-析出机制。     

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。     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

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.     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

The Mirror with Patterns of Auspicious Animals and Grapes——Exquisite cast mirror and the technology of surface tin-enrichment by rubbing-in and infiltration of tin-rich powder

<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also     

The 9th China International Diecasting Congress & Exhibition

The 9th China International Diecasting Congress ＆ Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

RARE METALS Volume Contents

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