671 nm红光泵浦Cr:LiSAF可调谐激光器的研究

提出一种新的泵浦Cr：LiSAF可调谐激光器的方式，并用国内的Cr：LiSAF晶体作了初步实验．在实验中，经过反复的研究设计了一种简单，廉价的耦合系统．     

甲苯胺兰褪色光度法测定Cr(Ⅵ)

基于H2O2催化TB—Cr(Ⅵ)褪色反应,建立了测定Cr(Ⅵ)的方法.该方法简单快速,线性范围在0～0.624mg.L-1,标准偏差为S=0.014(n=11),用于模拟试样回收率测定,回收率在97.6%～98.6%.     

Influence of Cr2O3 additive and sintering temperature on the structural characteristics and piezoelectric properties of Bi4Ti2.95W0.05O12.05 Aurivillius ceramics

In this paper, Cr_2O_3(0–0.4 wt%) as an additive was added into Bi_4Ti_(2.95)W_(0.05)O_(12.05)(BITW) for preparing a kind of W/Cr co-doped BIT(BITW-yCr) Aurivillius ceramics, both W~(6+) and Cr~(3+) are considered to substitute Ti~(4+) in the [TiO_6] octahedron of BIT. Besides the orthorhombic Bi_4Ti_3O_(12) as the major phase, BITW-yCr ceramics also contain the cubic Bi_2Ti_2O_7 as the second phase which was formed due to the doping effect of WO_3, but its formation could be depressed by the addition of less Cr_2O_3. Additionally, the cell parameters of BITW ceramics are also changed by the incorporation of Cr_2O_3, as the distortion degree of the orthorhombic structure(a/b)increases firstly and then decreases with its addtional amount(y). On the other hand, the grain growth of BITWyCr ceramics is mainly controlled by the sintering process, there a higher sintering temperature results in a larger grain size. In comparison to BIT ceramics, BITW-yCr ceramics with less Cr-addition(y=0–0.2) require a higher sintering temperature to attain the best dense state, moreover, as y increases, the sintering temperature to gain the highest piezoelectric activity also increases. Finally, BITW-0.2Cr which was sintered at 1150 °C exhibits a higher piezoelectric activity than the others, which could be attributed to its larger orthorhombic distortion and larger grain size, its ideal piezoelectric constant(d_(33)=28pC/N) provides it with great applying potentiality.     

铂铬共掺杂纳米TiO2薄膜的制备及其光催化性能

采用溶胶 凝胶法制备了铂铬共掺杂纳米TiO2薄膜,并用AFM、XRD、UV Vis等对薄膜进行了表征。实验结果表明,铂铬共掺杂TiO2薄膜粒径约为32 nm;厚度为290 nm左右时,薄膜对亚甲基蓝的降解率在2.5 h达到95％左右;共掺体系的最佳掺杂量为n(Cr)∶n(TiO2)=0.4%, n(Pt)∶n(TiO2)=0.03%, 此时TiO2薄膜对亚甲基蓝有良好的降解效果,优于同等条件下制备的纯TiO2薄膜和铂、铬单掺杂TiO2薄膜。     

一种1Cr18Ni9不锈钢基片PTC厚膜电路的实现方法

为了将PTC(positive temperature coefficieat)电子浆料以厚膜电路的形式制备在不锈钢基片上,并把不锈钢本体作为散热器,引出电极利用PTC效应制成可控电热元件.方法:提出基于1Cr18Ni 9不锈钢基片的PTC厚膜电路的组成结构,并根据1Cr18Ni 9的膨胀系数和电路元件的电气特性实现了厚膜电路PTC电子浆料的应用设计技术.结果显示以PTC厚膜电路材料组成的可控电热元件,其功率密度高达200 W/cm2;其电阻膜层的表面加热速度可达200-300℃/s;其使用寿命达到1 万小时以上.可见与传统的电热合金材料、陶瓷基片加热器以及元件组合的加热器相比,本实现技术电路具有功率密度大、响应速度快、加热温度可控等优点.     

Cr掺杂浓度对ZnO基稀磁半导体生长结构的影响

采用射频磁控溅射设备在本征抛光Si(100)衬底上沉积Cr掺杂ZnO薄膜,分析不同掺杂浓度对薄膜的生长结构的影响.分别用XRD、SEM和XRF来表征薄膜的晶相结构、表观形貌和掺杂浓度.实验结果表明,掺杂浓度为2.10%的Zn1-xCrxO薄膜,出现了更好C轴取向性,衍射峰半高宽较窄,样品表面平滑致密,晶粒较大为3.555 nm.     

预处理对Cr系脱氢催化剂性能的影响研究

采用浸渍法制备了Cr系脱氢催化剂，考察在不同预处理条件下催化剂的脱氢性能，结果显示通过水蒸汽预处理的cr催化剂性能明显得到改善，随着水蒸汽处理时间延长，cr催化剂转化率降低，但稳定性提高．通过XRD、XPS等技术对反应前后催化剂样品进行表征，发现水蒸汽处理前后催化剂各组分含量、价态基本保持不变，且催化剂具有良好的再生性．     

Morphology and kinetics evolution of γ′ and γ phases in Ni-xAl-(20-x)Cr at % alloys

The morphology and kinetics evolution of γ' and γ phases in Ni-xAl-(20-x)Cr at%(x=7.5-13.7) alloys aged at700℃ were studied by utilizing the phase-field simulation.The separated γ' phases from γ matrix in low Al content(x 13) alloys transferred to the interconnected morphology with separated y phases in high Al content(x 13) alloys,and long-time aging produced near cubic γ' phase.The coarsening rate of γ' phase declined firstly when the Al content x=7.5-9.0,then increased sharply as x ranges from 9 to 12,while the coarsening rate of γphase declined directly.Additionally,the average edge-to-edge distance of neighboring γ' phases showed a threestage variation when Al content x 9,it decreased to minimum value and increased slowly then decreased again with aging time.In contrast,when 9 ≤ x 13,the average particle distance of γ' phase decreased to a nearly constant value.With the coarsening of y phase,their average particle distance increased.The kinetics evolution was clarified with the combined variations of the particle number density,average particle radius and volume fractions in the continuous composition Ni-xAl-(20-x)Cr at% alloys.     

铜基Cu－Co－Cr－Si电极合金的研究

本文在含Ｃｏ，Ｃｒ，Ｓｉ的铜合金中Ｃｏ_５Ｃｒ_３Ｓｉ_２相的行为等研究基础上，进一步研究这个合金体系在热处理过程中各相形成和相关系的变化。金相分析、Ｘ射线衍射分析和各相显微硬度数据表明，合金固溶时效处理中的强化相为αＣｏ_２Ｓｉ，而μＤＴＡ数据表明，Ｃｏ_５Ｃｒ_３Ｓｉ_２相是在合金熔炼过程中形成的。从实验给出的数据和有关相图等资料的分析，大致给出了合适的合金成分选择范围。     

晶型三氧化二铬的研制

采用湿法制备晶型Ｃｒ＿２Ｏ＿３，产品各项指标与文献报道相符。该法有一定推广价值。