NiAl金属间化合物的热爆合成过程研究

以Al粉和Ni粉为主要原料，采用自蔓延高温合成技术，制备Ni—Al基金属间化合物。绘制了热爆反应曲线、描述了热爆反应的过程，分析了热爆反应机理及产物的显微组织特征，研究了热爆反应的边界条件以及各种反应参数对热爆反应的影响。研究结果表明，升温速率和颗粒尺寸对热爆反应均有不同程度的影响。提高升温速率、减小颗粒尺寸均可缩短热爆反应的起始时间，降低热爆反应的起始温度。初步确定了反应起始温度低于Ni—Al系的最低共晶温度（640℃），Ni—A1系的热爆反应是由固一固扩散反应引发的，Ni-32Al的反应产物为单相、均一的NiAl相。     

W含量及预热温度对Ti—W—C体系燃烧合成产物的影响研究

研究了W含量及预热温度对Ti-W-C体系燃烧合成产物相组成及粉末形貌的影响。研究结果表明，体系W含量减少，或燃烧之前进行预热，通过提高体系的燃烧温度，其燃烧反应机制由扩散－固溶机制转变为熔化－溶解－析出机制；结果，燃烧反应随之完全,有利于合成单相（Ti,W)C粉末，且产物粉末粒度增加，同时合成单相所需的预热温度随W含量增加而提高。     

燃烧合成Mg2Ni的影响因素

用XRD和SEM对Mg-Ni体系燃烧合成产物进行了研究。结果表明：Mg—Ni压坯预热至440℃以上均可热爆合成Mg2Ni，且预热速度越大产物越致密；过大的压坯密度，降低了体系的燃烧温度，影响Mg，Ni间的反应程度；而对于细小的Mg粒，由于较高的燃烧温度，导致合成产物出现严重的烧结现象；此外热爆合成产物在一定温度下适当的保温，有助于提高Mg2Ni的纯度。     

高能球磨形成具有明显玻璃转变的Ti50Cu20Ni24Si4B2非晶态合金

在高能球磨作用下，名义成分为Ti50Cu20Ni24Si4B2的元素粉末混合物可通过固态反应非晶化。差示扫描量热分析（DSC）表明，球磨获得的非晶相在发生晶化转变之前出现明显的玻璃转变。过冷液态温度区的宽度（ΔTx）可达到57K。非晶态Ti50Cu20Ni24Si4B2合金加热时的转变由一步完成。同时形成立方结构的（Ni,Cu)Ti相和其它未知相。为共晶型转变。随后发生晶化产物的进一步晶粒长大。非晶态Ti50Cu20Ni24Si4B2合金的约化玻璃转变温度（Trg)为0．56。     

TiC-Ni金属陶瓷自蔓延高温合成中的显微组织演变

用燃烧波淬熄法研究了TiC-Ni金属陶瓷自蔓延高温合成(SHS)中的组织演变,淬熄试样中保留了未反应区、反应区和已反应区.用扫描电子显微镜观察了燃烧反应中显微组织的转变过程,用能谱仪分析了各微区的成分变化,测量了燃烧温度Tc和燃烧波蔓延速度,并用XRD分析了反应产物的相组成.结果表明,TiC-Ni金属陶瓷自蔓延高温合成(SHS)的机理为溶解-析出机制,镍粉与钛粉的固态扩散导致低熔点Ti-Ni溶液形成,Ti、Ni、C粉粒逐渐向Ti-Ni溶液中溶解,当Ti-Ni-C溶液中的Ti和C浓度饱和时,从中析出TiC颗粒,同时形成粘结TiC颗粒的Ni3Ti基体.分析结果表明,该体系的燃烧合成具有不完全性,最终产物中残留少量Ni3Ti2 NiTi共晶体,这种反应的不完全性是由于使用了较粗的Ti粉和Ni粉.     

电场诱导Fe-Ti-C体系低温燃烧合成显微组织演变

采用Gleeble-1500D热模拟机，通过对质量分数55％（Ti＋C）-45％Fe粉末压坯分别升温至250～800℃的解析实验，研究Fe-Ti-c体系在电场诱导下低温燃烧合成的显微组织演变。结果表明：在电场和大热流密度的共同作用下，体系的点火温度可大幅降低。当加热温度在250～350℃之间，体系虽未发生化学反应，但显微结构在一定程度随温度而发生变化；当加热温度在350-470℃范围内，体系被点燃发生“热爆”现象，而在燃烧合成反应前期，合成TiC的反应优先发生；当加热温度提高到470-670℃，合成TiC反应发生的同时还伴随有合成Fe2Ti的反应；然而随加热温度进一步提高到670-800℃，Fe2Ti会发生部分分解，进而使得合成TiC的反应继续进行。当温度达到800℃左右，该合成反应全部完成，产物由Fe、TiC和少量Fe2Ti组成。此外，通过合成反应所得呈圆球状、细小的TiC颗粒均匀地分布在Fe基体中，且随加热温度的提高而有所长大。     

燃烧合成方式对形成Ni_3Al的影响

为研究自蔓延和热爆两种燃烧合成方式对产物Ni3Al组织的影响,采用扫描电子显微镜(SEM)观察对比了合成试样中的不同显微组织,利用X射线衍射(XRD)分析比较了合成产物相的差别,并通过透射电镜(TEM)比较了两种方式下合成相粒子析出情况。结果表明:自蔓延反应产物形成共晶组织,热爆反应则生成枝晶组织;虽然两种方式反应物的XRD分析结果相同,但是自蔓延反应产物的相峰强度显著高于热爆反应产物;热爆反应产物相粒子产生的偏聚比自蔓延反应产物相明显。     

引燃模式对自蔓延高温合成Al-Ti-C中间合金的影响

利用Al、Ti、C粉末原料,采用自蔓延高温合成技术(SHS)合成了Al-Ti-C中间合金晶粒细化剂。借助X射线衍射(XRD)、扫描电子显微镜(SEM)研究了引燃模式对自蔓延高温合成反应过程及合成产物组织形态的影响。结果表明:两种引燃模式下自蔓延高温合成的Al-Ti-C中间合金由Al、Al3Ti和TiC组成,引燃模式对Al-Ti-C的组织形貌产生重要影响,自蔓延模式下燃烧温度低,合成产物中的第二相粒子细小分散,而热爆模式下燃烧温度高,Al3Ti、TiC长大聚集,影响其晶粒细化性能。     

成分配比和B-Fe对高温合成Ti-Al的影响

以Ti粉、Al粉、B-Fe为主要原料，采用自蔓延高温合成技术，制备Ti-Al基金属间化合物。研究了自蔓延高温合成技术，成分配比，B-Fe以及高温装炉对热爆反应的影响，分析了热爆反应机理以及热爆产物显微组织。结果表明：随Al含量的减少、加热速度的提高，热爆起始时间缩短、热爆反应峰值增加；加入适量B-Fe可以延缓Ti-Al基金属间化合物的热爆反应，抑制Ti3Al的择优生长，达到细化晶粒的效果。反应产物主要为针状或细棒状α2(Ti3Al)和γ(TiAl)两相。     

Ti-C-Al-Ni系热爆反应产物形貌及热力学分析

研究Ti-C-Al-Ni系热爆合成NiAI/TiC的形貌，并进行了热力学分析。结果表明：Ti、C含量对产物形貌有显著影响。当体系中Ti、C含量较少（≤15%）时，TiC和NiAl均为圆球状。随着Ti、C含量的增加，NiAl发生熔化；当Ti、C含量达50%左右，TiC颗粒镶嵌在熔融的NiAl基体上，形成较致密的金属间化合物基复合材料；Ti、C含量进一步增加，TiC颗粒变得粗大且不规则，少量NiAl覆盖于其上。产物形貌实际上是由燃烧反应的绝热温度Tad和瞬时液相量所决定的。随着TiC含量的增加，反应体系的Tad提高，NiAl液相量增加，当Ti、C含量达50%时，合成产物中液相量达到最大。     

新试剂N-烯丙基-N＇-安替比林基硫脲光度法测定矿样中微量金

研究了新试剂N-烯丙基-N'-安替比林基硫脲与Au(Ⅲ)的显色反应.结果表明在pH=3.8～4.4的HAc-NaAc缓冲体系中,Au(Ⅲ)与该试剂形成12的络合物,其最大吸收峰位于275.0nm,表观摩尔吸光系数ε275.0=2.39×104L·mol-1·cm-1,Au(Ⅲ)含量在0～24.0μg/25mL内服从比尔定律.方法操作简便,选择性高.用于金矿石中微量金的测定,结果令人满意.     

Improvement of image characteristics in high-voltage computed tomography (CT) by applying a compressed-sensing (CS)-based image deblurring scheme

We have established a high-voltage computed tomography (CT) system with a 1–3 MV LINAC x-ray generator for industrial nondestructive testing. However, reconstructed CT images are typically blurred, limiting its image performance, mainly due to the finite focal spot size of the x-ray source, aspects inherent to detector such as the detector pixel size and the detector resolution, and the reconstruction procedure as well. Thus the recovery of the reconstructed CT images from their degraded version is essential for improving the image characteristics. In this work, we investigated the compressed-sensing (CS)-based deconvolution scheme for more accurate image deblurring in CT. We implemented the proposed image deblurring algorithm for CT and performed a systematic simulation and experiment to demonstrate its viability. Our results indicate that the proposed deblurring scheme appears to be effective for the blurring problems in CT and is applicable to improve its present image characteristics.     

Zinc oxide (ZnO) grown on flexible substrate using dual-plasma-enhanced metalorganic vapor deposition (DPEMOCVD)

This study investigates the temperature dependence of zinc oxide (ZnO) grown on polyestersulfone (PES) flexible substrates using the dual plasma-enhanced metal–organic chemical vapor deposition (DPEMOCVD) system. The proposed method uses a direct voltage (DC) and radio-frequency (RF) plasma system. The group-VI precursor, oxygen (O₂), can be completely ionized by the DC plasma system. The effect of optimal DC plasma power on ZnO thin films is thoroughly investigated using X-ray diffraction (XRD). The experimental results indicate that the crystalline structure and optical and electrical properties of ZnO thin films grown on PES substrates are dependent on the deposition temperature. The optimum deposition temperature for ZnO thin films deposited on PES substrates is 185 °C, whereas the DC and RF plasma power is 1.8 W and 350 W, respectively. Additionally, the wettability characteristic regarding the UV irradiation time was assessed by measuring the water contact angle. Under the UV irradiation for 60 min, the ZnO film grown at 185 °C represents a low contact angle of 5°, which approaches to a superhydrophilic surface.     

Selective separation of Cu(II), Zn(II), and Cd(II) by solvent extraction

An experimental investigation was presented on the separation of Cu (II), Zn (II), and Cd (II) from a rich sulfate leachate of zinc slag by solvent extraction. The results of orthogonal experiments indicate that LIX 984N is highly selective and very efficient in the extraction of Cu (II), and the analysis of variance indicates that the sequence of parameters according to their influence on the separation efficiency is phase ratio>LIX 984N concentration>pH value>extraction time. The optimal condition for copper extraction is obtained as 25% of LIX 984N concentration, 7 min of extraction time, 3:2 of phase ratio O/A, and pH=1.7. The separation of Zn (II) and Cd (II) was performed after the copper extraction from the raffinate. Comparative analysis of the separation with di-2-ethylhexyl phosphoric acid (D2EHPA), D2EHPA-tributyl-phosophate (TBP) synergistic extracting system, and 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester (HEHEHP) was made at pH=2.0. It is demonstrated that the extraction efficiency with D2EHPA is improved after being saponified by sodium hydroxide, and D2EHPA-TBP synergistic extracting, as well as HEHEHP, has a superior selectivity to Zn (II) over Cd (II).     

The Korea Advanced Manufacturing System (KAMS) Project

The Korea Advanced Manufacturing System (KAMS) is one of the Highly Advanced National (HAN) Projects planned to achieve significant technological advances in Korea. The aim of this project is to create new processes and technologies for managing and integrating manufacturing systems. The key to sustaining economic growth and surviving global competition is to develop advanced manufacturing systems technology. The Korea Institute of Industrial Technology (KITECH) began this project in 1992 with support from the Ministry of Trade, Industry and Energy and the Ministry of Science and Technology. The project is divided into three phases, each phase consisting of project groups which include several research projects. The main project groups are ‘next-generation machining system' and ‘assembly and inspection system for electronic products'. The names of research projects are listed, and brief explanations are also introduced in this paper. The KAMS Project is expected to result in many benefits for manufacturing industry. The increase in productivity and system accuracy, and reduction in lead-time, will give renewed vitality to Korean manufacturing industry.     

金属间化合物（Fe60Ni40）3（V98Ti2）的蠕变断裂

对有序金属间化合物(Fe_(60)Ni_(40))_3(V_(98)Ti_2)的蠕变断裂行为进行了初步研究。用透射电镜观察了稳态蠕变过程中位错亚结构的变化,发现存在大量的堆垛层错和成对位错以及较高密度的位错网络。对断口及近断口剖面的扫描电镜观察指出,晶界上空洞所形成的沿晶断裂是(Fe_(60)Ni_(40))_3(V_(98)Ti_2)蠕变断裂的主要机制。     

兔肝脏中羟基磷灰石-阿霉素缓释剂的释放

目的 观察羟基磷灰石-阿霉素抗癌复合物局部注射,阿霉素在体内的释放过程及其抗肿瘤作用。方法 在B 超引导下向兔肝左叶内注入羟基磷灰石-阿霉素抗癌复合物。应用荧光分光光度仪测定注射羟基磷灰石-阿霉素抗癌复合物后,阿霉素在组织及血浆中的浓度,并与无羟基磷灰石的对照组比较。结果 此复合药物可在组织中维持有效治疗浓度1000 ng·g^-15 d 左右,同时与对照组相比注射后即时外周血浆浓度下降约1/2 。结论 该复合药物局部应用可提高及维持组织有效治疗浓度,减少毒副作用。     

以产品数据仓库为核心的并行设计过程

本文阐述了以数据仓库（ＤＷ）为核心的并行设计过程邮基于ＤＷ的并行工程（ＣＥ）的实施模式；将ＤＷ技术与人工智能（ＡＩ）技术结合提出了基于ＤＷ的ＣＥ黑板结构的思想，并设计了基于此的并行产品设计系统的体系结构。     

Preparation and Characterization of Europium-Doped Nanohydroxyapatite (Eu-nHA) Fluorescent Agent

采用湿法化学合成含铕纳米羟基磷灰石(Eu-n HA),并用透射电镜(TEM)、X射线衍射仪(XRD)、元素光谱分析、荧光分光光度计及荧光显微镜成像等进行分析观察。结果表明:稀土元素铕被正确掺入纳米羟基磷灰石晶格内,所制备的含铕纳米羟基磷灰石(Eu-n HA)纳米粒径为5~15 nm(宽)×15~30 nm(长)。该纳米材料在适宜紫外光激发下能明确产生红色荧光。5D0-7F1和5D0-7F2跃迁是形成该光致发光的重要原因。本研究制备的Eu-n HA有望成为一种新的纳米荧光剂应用于生物医学领域。     

EXTRACTION MECHANISM OF CERIUM(IV) AND FLUORINE(I)IN THE SEPARATION PROCESS OF BASTNASITE LEACHSOLUTION BY CYANEX 923

The extraction equilibrium of cerium(IV) and fiuoriue(l) from II2SO4 solution tyCyanex 923 was studied. The extraction mechanism of Ce(IV) and F(I) by Cyanex923 was determined by the method of slope analysis. The results showed that Cyane923 can extract HF as HF.L and Ce4+ together with HF as Ce(HF)(HSO4)2(SO4).2Lby which HF comes into the organic phase mainly when there is Ce4+ in the solution,where L is the extractant. Temperature did not affect the extraction. The IR spectraof purified Cyanex 923 saturated with Ce(IV) and HF were discussed.``