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1.
磁性ICF玻璃靶丸的化学镀工艺   总被引:2,自引:2,他引:0  
 采用化学镀工艺在ICF玻璃靶丸表面包覆了一层磁性的Ni-P合金镀层,制备出磁性ICF玻璃靶丸。研究了化学镀主盐质量浓度、还原剂质量浓度、络合剂质量浓度、施镀温度及镀液pH值对沉积速率与镀液稳定性的影响,获得了化学镀制备磁性ICF玻璃靶丸的最佳工艺为:主盐硫酸镍30 g/L,还原剂次亚磷酸钠30 g/L,络合剂柠檬酸钠50 g/L,pH值10,温度(40±2) ℃。  相似文献   

2.
 采用自行设计的微球电沉积装置,建立了空心聚苯乙烯(PS)微球的电化学沉积金工艺。实验条件为:电源输出电压0.7~0.8 V,电流密度2.0 mA·cm-2,镀液温度45 ℃,阴极转速250 r·min-1,镀液流速7 mL·min-1·cm-2。在此工艺条件下制得的空心金微球对称性和厚度均匀性良好,表面粗糙度低于500 nm,微球表面沉积金速率约为6 μm·h-1。  相似文献   

3.
 讨论了PDC材料烧结过程中钴在金刚石层中的固相扩散、钴液熔渗、两次钴高浓度峰的“波浪”式迁移过程中的运动规律及其作用机制,并根据实验观测的数据进行了有关计算。结果表明:在5.8 GPa、1 300 ℃条件下,钴的扩散系数D≈1.6×10-7 cm2/s,是一般常压及相同温度条件下钴固相扩散系数(3×10-10 cm2/s)和相同压力条件下钴的液相扩散系数(5×10-5 cm2/s)的中间值;对于粒度W≥10 μm的金刚石烧结体系,钴液熔渗作用时间非常短暂,略大于0.5 s,而对于W≤1 μm的超细金刚石烧结体系而言,钴熔渗作用时间为28 s,比粒度W≥10 μm的金刚石烧结要长得多;两次钴高浓度峰的迁移速度分别约为50 μm/s和100 μm/s。  相似文献   

4.
电沉积法制备的泡沫镍的晶体结构与磁性能   总被引:1,自引:2,他引:1       下载免费PDF全文
 采用X射线衍射仪、振动样品磁强计分别测试了电沉积法制备的泡沫镍的晶体结构和磁性能,研究了电流密度、温度、占空比、脉冲频率对镍沉积层的晶体结构和磁性能的影响;并用扫描电子显微镜、透射电子显微镜观察了泡沫镍的组织结构与微观形貌。制备出的3维网络状泡沫镍密度为0.25 g/cm3,孔隙率为97.5%、孔径分布为400~500 μm。沉积层大颗粒粒径为1 μm,沉积层晶粒尺寸在10nm以下;泡沫镍为超顺磁材料,具有低的矫顽力和高的磁导率,其磁导率和饱和磁化强度随沉积层晶粒尺寸的增加而增大。  相似文献   

5.
用化学镀方法在碳纳米管表面沉积了具有不同镍/钴成分配比的镍钴磷合金层.讨论了Co2+与Ni2+的浓度比、镀液温度、pH值对沉积速率的影响.并利用场发射扫描电镜、透射电镜、X射线衍射仪、能谱仪和磁性测量仪对镍钴磷包覆碳纳米管进行了系统的结构和性能表征.结果表明:当镀液中Co2+与Ni2+的浓度比为1,pH值为9时沉积速率最大;镀液温度的升高会使沉积速率增大.磁性测试结果显示碳纳米管表面镀覆Ni-Co-P镀层后,其磁性能对镀层中的Ni、Co相对含量有强烈的依赖性.当Co2+: Ni2+=2:1时,饱和磁化强度最大.矫顽力分别在Co2+: Ni2+=1:2和Co2+: Ni2+=4:1时有2个峰值; 而磁导率分别在Co2+: Ni2+=1:4和Co2+: Ni2+=4:1时有2个峰值.  相似文献   

6.
 采用阻抗匹配法测量了两种低密度(ρ0=0.45 g/cm3和ρ0=0.47 g/cm3)硅橡胶在2.5~15 GPa压力范围内的冲击雨贡纽参数,p-up和us-up曲线,并采用最小二乘法拟合出C0,λ′和λ″的值。实验结果与理论预估值符合较好。  相似文献   

7.
红外用CVD ZnS多晶材料的研制   总被引:1,自引:0,他引:1  
论述了制备红外用CVD ZnS多晶材料的化学气相沉积工艺和热等静压处理工艺。针对CVD ZnS多晶材料具备优良的光学和力学性能,采用化学气相沉积工艺和热等静压处理技术成功研制出大尺寸多晶材料,其最大尺寸达到250mm×15mm。测试了CVD ZnS样品的各项光学、力学性能指标。样品的全波段透过率均接近ZnS材料的本征水平,折射指数均匀性优于2×10-5,在1.06μm的吸收系数为2×10-3cm-1,抗弯强度达到104MPa。  相似文献   

8.
0.1~800 MPa压力下方解石拉曼光谱的实验研究   总被引:2,自引:0,他引:2       下载免费PDF全文
 利用石英的拉曼谱峰与温度和压力的关系,检验了在金刚石压腔中用方解石拉曼谱峰确定体系压力的可行性,并初步确定了在常温下方解石的拉曼谱峰与压力的关系。实验研究结果表明:在实验的压力范围内方解石稳定,且其1 085 cm-1 谱峰约为石英464 cm-1谱峰的3倍强度,因此非常适合作为热液金刚石压腔的压力标定物。在温度26 ℃、压力0.1~800 MPa条件下,方解石的拉曼谱峰(1 085 cm-1)随着压力的增加,呈线形增大,其关系式为:p(MPa)=192×(νp-1 085)-21.8,1 085 cm-1p<1 090 cm-1。  相似文献   

9.
空腔铜靶的化学镀制研究   总被引:1,自引:1,他引:0  
 介绍了在预处理芯轴(聚甲基丙烯酸甲酯)表面采用化学镀的方法制备铜空腔的技术,研究了镀液中硫酸铜含量、甲醛含量,镀液pH值、温度等对化学镀铜沉积速率和溶液稳定性的影响。根据实验确定了适宜的化学镀铜工艺规范:硫酸铜质量浓度10~20 g/L,TART·K·Na质量浓度10~30 g/L,EDTA·2Na质量浓度10~28 g/L,甲醛体积浓度10~25 mL/L,添加剂质量浓度10 mg/L,pH值12~13,温度35~65 ℃。通过该工艺制备出的镀层厚度达到10~25 μm,均匀性达到95%,表面无砂眼、裂纹等缺陷,刻蚀芯轴后空腔能自持。该方法为ICF研究制备金属或合金材料靶提供了新的途径。  相似文献   

10.
高岭石的高温高压相图及其地学意义   总被引:1,自引:1,他引:0       下载免费PDF全文
 用阻抗匹配法和PZT压电探针技术,在100 GPa的冲击压力范围内测量了初始密度分别为1.375 g/cm3和2.001 g/cm3两种孔隙度叙永石样品的Hugoniot状态方程。根据其pHH线所给出的高温高压相变点,用Grüneisen状态方程计算其相变点压力所对应的温度,并结合常压下受热相变的温度值,建立了“高岭石/Al2O3+SiO2+H2O”的温度-压力相平衡图。通过该相图与线性地热线的交点推断:高岭石至少可在上地幔50 km深处作为一种含水(OH-)矿物而稳定存在;或在俯冲板块中至少于133 km深处作为一种含水(OH-)泥质沉积物的过渡相而存在。  相似文献   

11.
在软X射线掠射光学系统筒状反射镜的加工过程中,根据对反射镜内表面镍磷合金镀层的质量要求,采用镍盐还原法对筒状微晶玻璃反射镜的内表面进行了活化,并对在含有30g/LNiSO4.6H2O、30g/LNaH2PO2.H2O、25g/LNa(CH3COO).4H2O、18g/LC6H8O7、10mg/L添加剂的镀液中沉积镍磷合金镀层的工艺方法进行了探索。对得到的镍磷合金镀层的结合力、抗腐蚀能力等进行了测试。结果表明,采用此法镀制的镍磷合金镀层结合力达到4B级,耐蚀性好,能够满足光学精密抛光的要求。  相似文献   

12.
《Composite Interfaces》2013,20(8):659-669
In order to obtain beech wood substrates with new functions as conductive materials and to develop their utilities in industrial fields, the technique of electroless nickel coating on the beech wood substrate was employed. The influence of complexing agent concentration [Na2EDTA·2H2O] on the nickel surface resistivity was studied. The process conditions were Ni(CH3COO)2·4H2O 0.103?mol/L, CH3CHOCOOH 18.18?mL/L, N2H5OH 54.54?mL/L, NaOH 0.193?mol/L, pH value of 9.5, temperature of 75?°C, and the complexing agent concentration varied between 0.012 and 0.061?mol/L. By means of XRD, EDXRF, and SEM, the chemical composition and morphology of the prepared films were investigated. The results showed that when the complexing agent concentration increased from 0.012 to 0.061?mol/L in the electroless nickel coating baths, the gained nickel mass on the beech wood substrate decreased from 17.04 to 9.03?mg/cm2, the nickel crystallite sizes reduced from 16.1 to 1.41?nm and the electric measurements demonstrated that the nickel surface resistivity rose from 0.004 to 192.16?kΩ/cm2.  相似文献   

13.
Nickel hydroxides with hierarchical micro-nano structures are prepared by a facile homogeneous precipitation method with different nickel salts (Ni(NO3)2·6H2O, NiCl2·6H2O, and NiSO4·6H2O) as raw materials. The effect of nickel sources on the microstructure and lithium storage performance of the nickel hydroxides is studied. It is found that all the three prepared samples are α-nickel hydroxide. The nickel hydroxides synthesized with Ni(NO3)2·6H2 or NiCl2·6H2O show a similar particle size of 20–30 μm and are composed of very thin nano-sheets, while the nickel hydroxide synthesized with Ni(SO4)2·6H2O shows a larger particle size (30–50 μm) and consists of very thin nano-walls. When applied as anode materials for lithium-ion batteries (LIBs), the nickel hydroxide synthesized with NiSO4·6H2O exhibits the highest discharge capacity, but its cyclic stability is very poor. The nickel hydroxides synthesized with NiCl2·6H2O exhibit higher discharge capacity than the nickel hydroxides synthesized with Ni(NO3)2·6H2O, and both of them show much improved cyclic stability and rate capability as compared to the nickel hydroxide synthesized with Ni(SO4)2·6H2O. Moreover, pseudocapacitive behavior makes a great contribution to the electrochemical energy storage of the three samples. The discrepancies of lithium storage performance of the three samples are analyzed by ex-situ XRD, FT-IR, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) tests.  相似文献   

14.
利用壳聚糖和膨润土,合成了具有良好吸附效果的天然高分子絮凝吸附材料。用傅里叶变换红外光谱仪表征了原料和产物的结构,通过改变吸附时间、温度、pH值和甲基橙溶液质量浓度等条件,考察了合成材料对甲基橙的吸附性能。结果表明,吸附剂用量为10g/L,温度20℃,溶液pH为4.70,吸附平衡30min后,甲基橙去除率达90%以上,其吸附过程符合Langmuir吸附模型,是放热过程。  相似文献   

15.
The nickel phosphorous catalyst coating was studied on the E-glass fiber by electroless deposition using sodium hypophosphite as a reducing agent in alkaline medium. The effects of deposition time, deposition temperature, pH of the solution, and amount of stabilizer used in the solution on the coating efficiency were investigated by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The XRD indicates the presence of amorphous and crystalline phases of Ni and nickel–phosphorous (NiP). From TGA, it is evident that the NiP coating increases the thermal stability and magnetic properties of the glass fiber. The bath temperature of 80 °C, pH of 9 to 9.5, and stabilizer concentration of 25 g/l are optimum to get a good and uniform coating of NiP on glass fiber. Carbon nanotubes were successfully coated on NiP coated glass fiber at a temperature of 700 °C.  相似文献   

16.
以葡萄糖为原料,通过一步水热法合成稳定性高的碳量子点,并用乙二胺使其表面氨基化。焦性没食子酸能使氨基化的碳量子点荧光明显猝灭,由此建立一种简便、高效检测焦性没食子酸的新方法。考察了缓冲体系p H、反应时间、反应温度等对焦性没食子酸测定的影响。结果表明,在pH=11.20的三酸缓冲溶液中,室温反应20 min时,体系的F0/F与焦性没食子酸的浓度呈良好的线性关系,其线性范围为4.0×10~(-6)~9.0×10~(-5)mol·L~(-1),相关系数r=0.997 4,检出限为3.5×10~(-6)mol·L~(-1)。该方法快速简便,适用于水样中焦性没食子酸的检测。  相似文献   

17.
Biocompatible, highly interconnected microporous poly(L-lactic acid) (PLLA) foams with nanofibrous structure, containing pores with average diameter below 1 μm and fibers with diameters of 102 nm scale, were prepared through the thermally induced liquid–liquid phase separation (TIPS) method consisting of quenching of the PLLA solution, freeze extraction with ethanol, and vacuum drying. Diverse foam morphologies were obtained by systematically changing parameters involved in the TIPS process, such as polymer concentration, solvent composition, and quenching temperatures. The morphology of different foams was examined by scanning electron microscopy to characterize the pore size and the pore size distribution. The results showed that most porous foams had a nanofibrous structure with interconnected open pores. In the case of using tetrahydrofuran (THF) as solvent, the higher the PLLA concentration, the smaller the average pore diameter and the narrower the pore size distribution. In the case of using the mixed solvents of THF/DOX (1,4-dioxane) with higher than 6/4 volume ratio, there appeared a maximum value of average pore diameter and a widest pore size distribution at 0.09 g/mL PLLA concentration. The average pore diameter of the foams increased with increasing DOX content in the mixed solvent and ranged from 0.2 to 0.9 μm depending on the process parameters. When the DOX content reached 60% by volume, the morphology of the foams contained some large closed pores with diameter ranging from 1 to 10 μm. By decreasing the quenching temperature, the average pore diameter of foams decreased and the pore size distribution became narrower. All the pore size distribution fit F-distribution equations.  相似文献   

18.
在pH 2.27的柠檬酸钠-盐酸缓冲溶液中,纳米金对氯金酸-盐酸羟胺生成较大粒径金颗粒这一慢反应具有较强的催化作用。较大粒径金颗粒在600~1 000 nm处有一个较宽的吸收峰。将纳米金标记羊抗人IgG获得免疫纳米金,免疫纳米金也具有相同催化效果。在一定条件下,金标记羊抗人IgG与IgG发生特异性结合生成纳米金免疫复合物。以16 000 rpm速度离心分离获得未反应的纳米金标抗上层溶液。以它作为催化剂催化氯金酸-盐酸羟胺微粒反应,700 nm处的吸光度A700 nm线性降低。其降低值ΔA700 nm与IgG在0.1~10 ng·mL-1范围内呈良好线性关系, 检出限为0.06 ng·mL-1。本法具有灵敏、快速和较高的特异性,用于定量分析人血清IgG,结果满意。  相似文献   

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