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61.
以TiCl3和氧化石墨(GO)为原料,采用简便的原位液相法制备了TiO2/石墨烯(RGO)纳米复合材料.利用XRD、SEM、XPS和UV-Vis光谱表征了其微观结构及性能,实验考察了复合材料光催化还原CO2性能,探究了其光催化反应机理.研究表明,TiO2/石墨烯纳米复合材料具有显著的光催化还原活性,光催化反应产物选择性高,反应6.0h甲醇的累积产量为3.43 mmol/L,石墨烯的协同效应提高了TiO2半导体的光催化活性和反应效率. 相似文献
62.
63.
Avalanche Phenomenon of Superthermal Electrons Measured by SDD with New SPHA during ECRH 总被引:1,自引:0,他引:1 下载免费PDF全文
Two high performance silicon drift detectors (SDD) are installed at the equatorial port with z = 0 and z = -16.4 cm on HL-2A tokamak, respectively. These SDDs combine with the new and non-conventional software pulse height analyser (SPHA ) successfully developed more recently by us to measure the time evolution of soft x-rays spectra, the thermal and superthermal electron temperatures. The high-quality three-dimensional figure of time evolution for soft x-rays energy spectra is easily obtained by combination of a new SPHA and computer. Therefore, the measurement accuracies and the time resolutions of thermal and superthermal electron temperatures are also improved. The enhancement phenomenon of superthermal electron during electron cyclotron resonance heating (ECRH) can be explained by the combination of superthermal electron avalanche theory and experimental parameters. 相似文献
64.
PIEZOELECTRIC Pb(Zr, Ti)O3 MICRO-DEVICES FOR SCANNING FORCE MICROSCOPY AND ULTRA-DENSITY DATA STORAGE 下载免费PDF全文
In this paper we report two types of micro devices based on Pb(Zr, Ti)O3 (PZT) thin films for improving the throughput of scanning force microscopy (SFM) or data storage using SFM. One is a piezoelectric cantilever array integrated with force sensor as well as z-actuator on each cantilever for parallel operation. The 125-μm-long PZT micro cantilever with a natural resonant frequency of 189 kHz has a high actuation sensitivity of 75 nm/V. Independent parallel images using two cantilevers of the array were obtained. The other is a novel micro-SFM device that is expected to replace the cantilever, the deflection detection unit, and the macro-fabricated scanner which is the bottle neck limiting the single probe acquisition rate. The bridge-structured device has shown a microscopy sensitivity of 0.32 nA/nm in vertical direction and actuation abilities of 70-80nm/±V in the lateral direction. 相似文献
65.
描述岩石破坏的非线性共振模型 总被引:1,自引:0,他引:1
从分子之间作用势出发,根据固体物理学理论和激光共振原理,提出了一种描述岩石破坏全过程微观机理的物理模型,并给出了相应的本构微分方程组,且与多种岩样的实验结果进行了对比。 相似文献
66.
以MgSO4·7H2 O和NaOH为原料,邻苯二甲酸氢钾(KHpht)作为络合剂,采用络合-水热法制备碱式硫酸镁(MOS)纳米线.考察了反应条件对MOS纳米线形貌的影响,并对产物进行了表征和分析.确定了制备MOS纳米线的较优条件:MgSO4浓度为0.3 mol/L,n(NaOH)/n(MgSO4)为2.5,n(KHpht)/n(MgSO4)为1.1,无水乙醇作为分散剂,水热合成温度160℃,反应时间10 h.所得到MOS纳米线形貌均匀,长度在10~20μm,直径在20~100 nm,纳米线沿[010]方向生长. 相似文献
67.
68.
By repeatedly pre-cleaning the sputtering chamber with Ar gas and in-situ isochronal annealing samples, NiSi films are successfully prepared on Si (100) substrates in a radio-frequency magnetron sputtering system. A comparison between the obtained NiSi and excess oxygen-contaminated Ni/Si films has been performed by EDX analysis of oxygen atomic content in both the films. Focused ion beam milling technology is employed to make the cross-sections of the samples for characterizing the NiSi film thickness and NiSi/Si interface roughness. The influences of nickel film thickness on the NiSi-film morphology and on the NiSi/Si interface roughness are studied. 相似文献
69.
Starting from a simplified model involving the interactions between co/our quark fields, colour-SU(3) gauge fields, and colour scalar fields, it is shown, to the lowest-order approximation in h, that the vacuum expectation value of the gauge fields is equivalent, mathematically, to the vacuum expectation value of the scalar fields. Based on this relationship, a soliton solution of the gauge fields is given by solving the Euler equation of the scalar fields. 相似文献
70.
对火焰原子吸收光谱法测定氯化物型卤水中微量铷时共存离子,包括钾、钠、钙、镁等的干扰作了试验,并根据试验结果对文献报道的火焰原子吸收光谱法测定简单卤水中铷的条件作了改进.试验表明:当在制作标准曲线时加入与试样中含量相近的上述离子,可抵消其干扰.按此条件,毋需任何预处理,即可直接测定铷.应用此方法分析了两件已知样品中铷量,所得结果与已知值相符.以此样品为基础加入铷标准溶液作回收试验,测得回收率在92%~108%之间. 相似文献