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1.
改进了胶片的制备工艺,提高了工业x光胶片的感光度,降低了涂布银量。研制的x光胶片,能满足一些精细材料和航空工业部门对工业x光胶片照相性能的要求。  相似文献   

2.
本文利用XRD,SEM,DTA及BET等现代仪器,研究了K-Zn-Ti层状金属氧化物(LMO)经HAc,NH4Cl交换前后的基本性能。结果表明:该LMO具有良好的离子交换性能,其面网间距由0.78nm分别增加到0.86nm和0.88nm。同时,比表面积由27m^2/g分别增加到30m^2/g和59m^2/g,可望作为大孔分子筛的制备原料。  相似文献   

3.
介绍一种新型隔热耐火材料,该板用MgO〉95%的烧结镁砂和Al2O3〉38%的漂珠的主要原料,以及适量的纤维,结合剂,添加剂研制出体积密度1.46g/cm^3,导热系数0.46W/m.K,抗折强度6MPa的镁质绝热板。  相似文献   

4.
氧化钇微粉的研究   总被引:5,自引:0,他引:5  
采用草酸钇沉淀,水蒸汽热分解法制备了Y2O3微粉,用X射线衍射对产品组成进行鉴定用扫描电镜对粒子分散状况及形貌进行观察,粉末粒径为0.42~0.87μm其比表面积为11.59~22.86m^2/g。  相似文献   

5.
本文利用浓度4~15%的低CO_2和剂量为0.6~4g/m ̄3的磷化铝对小麦、稻谷进行了混合熏蒸。多次试验表明:用浓度为8~12%的CO_2气体和浓度0.18g/m ̄3的磷化氢气体混合熏蒸能有效地杀死长角谷盗等12种常见害虫和粗脚粉螨等6种常见螨类及大量为害的书虱,处理后的粮食经渡夏储藏为安全粮。熏蒸24小时后仓内CO_2和PH_3达到均匀分布。  相似文献   

6.
应用XRD、TPR和催化活性评价手段,考察了CH_4与CO_2重整制合成气的负载型Ni催化剂的阈值效应.实验结果表明,在反应温度为750℃和空速为2 500 h~(-1),NiO载量为14.0%NiO/γ-Al_2_O3(相当于0.163 g NiO/gγy-Al_2O_3或0.077 g NiO/100m~2γ-Al_2O_3)催化剂具有最佳的催化性能,NiO在γ-Al_2O_3表面上分散阈值为0.238 g NiO/gγ-Al_2O_3(相当于0.112 g NiO/100m~2γ-Al_2O_3),能明显体现负载型Ni催化剂在重整反应中的阈值效应.  相似文献   

7.
高铬铸铁复合变质剂的研究   总被引:5,自引:0,他引:5  
通过实验室和生产条件下的试验,研制出一种适用于高铬白口铁的含Zn,Mg等元素的多元复合变质剂———Zn变质剂.采用Zn变质剂处理的高铬白口铸铁,初生奥氏体细小,碳化物孤立、圆钝,材料的冲击性αK≥8J/cm2,HRc≥60,其效果相当或优于VTi变质剂,悬殊成本低廉.采用SEM,EDAX和EPA等手段对Zn变质剂的变质作用进行了分析.  相似文献   

8.
光度分析法测定饮料中微量汞的研究   总被引:3,自引:0,他引:3  
研究了Hg(Ⅱ)-二苯基硫卡巴腙-TritonX-100体系测定饮料等食品中微量汞的新方法,该配合物Ⅱ_(max)=550nm,表观摩尔吸光系数ε_(550)6.6×10 ̄4L·mol ̄(-1)·cm ̄(-1),Hg ̄(2+)含量在0~30μg/25mL范围内遵守Beer定律,该法用于饮料等食品中微量汞的测定,获得了令人满意的结果.  相似文献   

9.
对四氯化锡加氨水中和制备二氧化锡气敏材料的方法进行了考察。二氧化锡经500℃灼烧3h,再于300℃下老化,其XRD谱图与700℃的烧所得二氧化锡的XRD谱图基本相同,但其比表面比后者大10m2/g,两者比表面之比为0.69;而在250℃下两种材料在清洁空气中的稳定电阻值(R0)之比为0.66;在500×10-6(体积比)乙醇气中的稳定电阻值(Rg)之比为0.685.前者对乙醇气的灵敏度稍优于后者。更适于用作气体传感器的基材。  相似文献   

10.
在pH5.3~6.6的HAc-NaAc缓冲介质中,有十二烷基硫酸钠存在,硫化物使Ag(Ⅰ)-5-Br-PADAP络合物的颜色减退。S2-在0~5μg/25mL范围,吸光度减弱与S2-浓度成正比。其表现摩尔吸光系数为1.2×105L·mol-1·cm-1。方法用于污水中硫化物的测定,结果满意。  相似文献   

11.
为了研究多层膜的腐蚀性能,促进多层膜在生产中的应用,采用电弧离子镀技术,通过调整环境N2和Ar气的时间比例在铜衬底上成功制备了不同调制周期的Ti/TiN多层膜.利用x 射线衍射谱和交流阻抗谱研究了该多层膜的结构和腐蚀性能.表面形貌显示,沉积的Ti/TiN多层膜具有明显的周期性,环境中N2和Ar气的时间比例决定了多层膜的调制周期,N2气时间越长,多层膜中TiN相层越厚.腐蚀性能测定表明,多层膜的调制周期影响其耐蚀性,当调制周期为550nm时,沉积膜的耐腐蚀性最好.  相似文献   

12.
Fe-Cr合金在Na_2SO_4盐膜下的热腐蚀行为   总被引:1,自引:0,他引:1  
研究表面涂覆20~25 g/m2和40~45 g/m2两种厚度Na2SO4盐膜的Fe-10Cr和Fe-20Cr合金在900℃空气中的热腐蚀行为.结果表明:涂盐量为20~25 g/m2和40~45 g/m2的Fe-10Cr和Fe-20Cr合金在腐蚀24 h后的腐蚀增重均明显大于未涂盐的两种合金在相同温度下纯氧化的增重;SEM分析表明涂两种厚度盐膜的Fe-10Cr合金的腐蚀膜均可分为3层,外层是Fe2O3,中间层以Fe2O3和Cr2O3的混合物为主,内腐蚀区有少量Cr的硫化物;两种涂盐量的Fe-20Cr合金表面均形成了较疏松的Cr2O3腐蚀层,腐蚀膜内层均未出现内硫化现象.  相似文献   

13.
The blend films with gelatin and poly(vinyl alcohol) (PVA) were prepared by a solution casting method. The compatibility between gelatin and PVA in the blend films was investigated. The transmittance, Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), thermogravimetry analysis (TG), and differential scanning calorimetry (DSC) were employed to characterize the resultant blend films. According to optic result, the opacity of the blend film at the ratio of 20/80 (w/w, Gel to PVA) was the lowest, indicating the best compatibility between Gel and PVA at the ratio. The results oflR, XRD, DSC, and TG revealed an intensive interaction and good compatibility between them in the blend film at the ratio. The mechanical properties and solubility showed that PVA content in the blend films obviously affected the elongation at break and solubility. The mechanical properties and water resistance of gelatin film may be improved by the introduetion of PVA.  相似文献   

14.
In order to investigate the effect of the thickness on the electrical conductivity of yttriastabilized zirconia(YSZ) film, the nanocrystalline columnar-structured YSZ film with thickness of 0.67-2.52 μm was prepared by magnetron sputtering through controlling the deposition time. All the sputtered films with different thicknesses consist of the main phase of cubic YSZ as well as a small amount of monoclinic YSZ. The thicker films exhibit a typical columnar grain structure based on the fractured cross-sectional SEM observations. The average diameters of columnar grains increase from about 40 nm to 100 nm with the film thickness from 0.67 μm to 2.52 μm according to TEM analysis. The thinnest YSZ film with 0.67 μm thickness shows the highest apparent electrical conductivity in the four films in 400-800 ℃ due to the contribution from the highly conductive film/substrate interfacial region. On the other hand, the real electrical conductivities of YSZ films increase with film thickness from 0.67 μm to 2.52 μm after eliminating the contribution of the film/substrate interface. The increasing film thickness leads to the grain growth as well as the decrement in the volumetric fraction of the resistive columnar grain boundary and a consequent higher real electrical conductivity.  相似文献   

15.
Magnetic Co-P thin films were prepared by electroless deposition. The experiment results show that the film thickness has a significant influence on the coercivity. While the film thickness varied from 300 nm to 5 μm,the coercivity dropped sharply from 45.36 to 22.28 kA/m. As the film thickness increased further,the coercivity varied slowly. When the thickness of the film was 300 nm,the deposited film could realize the coercivity as high as 45.36 kA/m,and the remanent magnetization as high as 800 kA/m .The ...  相似文献   

16.
运用射频溅射法在Si和LaNiO3/Si衬底上分别制备了高度(002)和(110)取向的ZnO薄膜.通过X射线衍射(XRD)和扫描电子显微镜(SEM)表征,发现ZnO/LaNiO3/Si薄膜的(110)取向度高达96%,ZnO/Si薄膜为(002)择优取向,两种薄膜表面均致密平整,晶粒尺寸小于80nm.光致发光结果表明,ZnO/LaNiO3/Si薄膜的光致发光峰主要为带边发射的紫外光,而ZnO/Si薄膜的光致发光峰主要为过量氧导致的缺陷引起的缺陷发光峰.因此,采用LaNiO3薄膜作为ZnO在Si衬底上生长的过渡层,能够有效抑制缺陷发光,改善ZnO薄膜的发光性能.  相似文献   

17.
采用形核 甲烷/氢气生长-辅助气体/甲烷/氢气生长的新工艺,在镜面抛光的单晶硅片上制备了金刚石膜,并用扫描电子显微镜和激光拉曼光谱等测试方法对薄膜的表面形貌和质量性能进行了表征;研究了添加辅助气体对已有金刚石晶型生长的影响.结果表明:以甲烷/氢气为气源时,金刚石膜生长率一般为1.8 μm/h,当分别加入氧气、二氧化碳、氮气时,其生长率都有所提高,其中加入二氧化碳时,其生长率是甲烷/氢气为气源的3倍多,但是加入氩气时,其生长率下降;通过新工艺,在加入氮气或氩气时,第一生长阶段为微米,而第二生长阶段为纳米尺寸,最后制备出具有微/纳米双层复合金刚石膜.  相似文献   

18.
采用溶胶-凝胶法(sol—gel)在聚乳酸(PLA)基膜上负载羟丙基甲基纤维素/二氧化硅(HPMC/SiO2)有机-无机杂化层,制备HPMC/Si02有杂化复合薄膜。表征和测试杂化复合薄膜的结构与性能。结果表明:当HPMC溶液体积分数为6%时,杂化复合薄膜的氧气阻隔性能比PLA薄膜的氧气阻隔性能提高了36倍,同时,杂化复合薄膜的拉伸强度优于PLA薄膜。  相似文献   

19.
LiH薄膜制备技术进展   总被引:1,自引:0,他引:1  
纳米厚度、表面光滑的氢化锂薄膜的制备研究具有十分重要的意义。综述了氢化锂薄膜的制备方法:电阻蒸发法和磁控溅射法。比较研究后认为这两种制备方法制备的氢化锂薄膜,表面粗糙度高,不能达到软x射线多层膜的要求。而脉冲激光气相沉积法可以制备表面超光洁,厚度最小为几个纳米的薄膜,是制备表面光滑的薄膜的一种重要制备方法。  相似文献   

20.
FePt thin films and [FePt/Ag]n multilayer thin films were prepared by magnetron sputtering technique and subsequent annealing process. By comparing the microstructure and magnetic properties of these two kinds of thin films, effects of Ag addition on the structure and properties of FePt thin films were investigated. Proper Ag addition was found helpful for FePt phase transition at lower annealing temperature. With Ag addition, the magnetic domain pattern of FePt thin film changed from maze-like pattern to more discrete island-like domain pattern in [FePt/Ag]n multilayer thin films. In addition, introducing nonmagnetic Ag hindered FePt grains from growing larger. The in-depth defects in FePt films and [FePt/Ag]n multilayer films verify that Ag addition is attributed to a large number of pinning site defects in [FePt/Ag]n film and therefore has effects on its magnetic properties and microstructure.  相似文献   

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