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1.
RP-HPLC同时测定饮料中安赛蜜、阿斯巴甜及苯甲酸 总被引:1,自引:0,他引:1
建立了一种同时检测几种饮料中安赛蜜、阿斯巴甜及苯甲酸的高效液相色谱检测方法。确定了最佳色谱条件:色谱柱:Diamonsil-C18(250mm×4.6mm,5μm);流动相:0.02mol/L硫酸铵:乙腈:磷酸=80:20:0.02(V/V/V);流速:1.0mL/min;紫外检测器检测波长:210nm。该方法加标回收率在94.5%—101.5%之间,精密度小于3%。实现了对碳酸饮料、茶饮料及橙汁中的安赛蜜、阿斯巴甜及苯甲酸的同时测定。 相似文献
2.
研究了冷原子与法布里-珀罗腔内拉盖尔-高斯横模强耦合相互作用体系的透射光谱, 分析了透射光谱与原子在腔中运动轨迹的关系. 结果表明, 与厄米特-高斯横模相比, 拉盖尔-高斯横模的腔场与原子的最大耦合系数几乎不随阶数的增加而变化, 使得探测光谱的对比度受模式阶数的影响较小. 在拉盖尔-高斯横模场分布的圆环边缘附近, 原子运动轨迹的微小偏移会引起透射光谱的很大变化, 因此在这些位置可以实现原子运动轨迹的高精度探测. 相似文献
3.
Characteristics of pentacene organic thin film transistor with top gate and bottom contact 下载免费PDF全文
High performance pentacene organic thin film transistors (OTFT) were
designed and fabricated using SiO2 deposited by electron beam
evaporation as gate dielectric material. Pentacene thin films were
prepared on glass substrate with S--D electrode pattern made from ITO
by means of thermal evaporation through self-organized process. The
threshold voltage VTH was --2.75± 0.1V in 0---50V
range, and that subthreshold slopes were 0.42± 0.05V/dec. The
field-effect mobility (μEF) of OTFT device increased with
the increase of VDS, but the μEF of OTFT device
increased and then decreased with increased VGS when VDS was kept constant. When VDS was --50V, on/off current
ratio was 0.48× 105 and subthreshold slope was 0.44V/dec.
The μEF was 1.10cm2/(V.s), threshold voltage
was --2.71V for the OTFT device. 相似文献
4.
Wang Jun Liu Xiang-Lin Yang An-Li Zheng Gao-Lin Yang Shao-Yan Wei Hong-Yuan Zhu Qin-Sheng Wang Zhan-Guo 《Applied Physics A: Materials Science & Processing》2011,104(4):1099-1103
Four novel dmit complexes: [(C2H5)4N][Ni (dmit)2], [(C3H7)4N][Ni(dmit)2], [(C2H5)4N][Au(dmit)2] and [(C3H7)4N][Au(dmit)2], abbreviated as EtNi, PrNi, EtAu, and PrAu, were synthesized. The third-order nonlinear optical properties of them in acetonitrile
solutions were investigated by using the Z-scan technique with 20 ps pulses width at 1064 nm. When the on-axis irradiance
at focus I
0 was 5.025 GW/cm2, the nonlinear refraction coefficient n
2, the third-order nonlinear susceptibility χ
(3), the molecular second-order hyperpolarizability γ of the four types of material were obtained with subject to Z-scan curves, and these indexes were with the magnitudes of
10−18 m2/W, 10−13 esu, and 10−31 esu, respectively. The nonlinear absorption coefficient β of Ni samples had the 10−12 m/W scale. The impact of different metals and cations on the third-order nonlinear optical properties of materials was analyzed.
Through the derivation, the result suggests that these dmit complexes are promising candidates for applications to nonlinear
optical devices manufacture in the near-infrared waveband. 相似文献
5.
In this paper,we use the a-plane InGaN interlayer to improve the property of a-plane GaN.Based on the a-InGaN interlayer,a template exhibits that a regular,porous structure,which acts as a compliant effect,can be obtained to release the strain caused by the lattice and thermal mismatch between a-GaN and r-sapphire.We find that the thickness of InGaN has a great influence on the growth of a-GaN.The surface morphology and crystalline quality both are first improved and then deteriorated with increasing the thickness of the InGaN interlayer.When the InGaN thickness exceeds a critical point,the a-GaN epilayer peels off in the process of cooling down to room temperature.This is an attractive way of lifting off a-GaN films from the sapphire substrate. 相似文献
6.
A Simple Route of Morphology Control and Structural and Optical Properties of ZnO Grown by Metal-Organic Chemical Vapour Deposition 下载免费PDF全文
Employing the metal-organic chemical vapour deposition (MOCVD) technique, we prepare ZnO samples with different morphologies from the film to nanorods through conveniently changing the bubbled diethylzinc flux (BDF) and the carrier gas flux of oxygen (OCGF). The scanning electron microscope images indicate that small BDF and OCGF induce two-dimensional growth while the large ones avail quasi-one-dimensional growth. X-ray diffraction (XRD) and Raman scattering analyses show that all of the morphology-dependent ZnO samples are of high crystal quality with a c-axis orientation. From the precise shifts of the 20 locations of ZnQ (002) face in the XRD patterns and the E2 (high) locations in the Raman spectra, we deduce that the compressive stress forms in the ZnO samples and is strengthened with the increasing BDF and OCGF. Photoluminescence spectroscopy results show all the samples have a sharp ultraviolet luminescent band without any defects-related emission. Upon the experiments a possible growth mechanism is proposed. 相似文献
7.
8.
将Fe2O3纳米粉体经一定浓度的H2SO4浸泡活化后制成纳米固体超强酸SO42-/Fe2O3,将其用于催化合成乙酸乙酯以考察其活性。利用均匀设计分析了超强酸制备过程及酯化反应过程中各因素的影响,研究结果表明较好的制备条件是:H2SO4浓度:2.5mol·L-1;浸泡时间:1h;活化温度:167℃;活化时间:1h,此时获得的固体超强酸SO42-/Fe2O3的粒径小于50nm。当催化剂用量为冰乙酸质量的5%,n(乙醇)∶n(冰乙酸)为3∶1,反应3.5h后乙酸的转化率高于80%。该催化剂经H2SO4溶液浸泡、活化再生后可重新使用,推断出其酸强度H0<-14.5。 相似文献
9.
Using ZnSO4 and TiCl4 as raw materials, nanometric TiO2-ZnO (ZnTiO3) is prepared at 180℃,0.8MPa by hydrothermal method. The effects of the reaction temperature and time on the nanometric TiO2-ZnO are also dis-cussed. XRD shows that the product is TiO2-ZnO (ZnTiO3) with noncrystal phase, and it changes to rhombic form above 870℃. TEM measurement indicates that the TiO2-ZnO is spherical particles, and the average diameter of the particles is 20nm. The UV light absorption properties are detected by UV spectrophotometer. The results show that the nanometric TiO2-ZnO has strong absorption at 200~370nm and at visible region. Photodegradation of dyes in an aqueous solution is investigated using nanometric TiO2-ZnO as a photocatalyst. The results show that after 60min illumination, the decolorization rate of the acidic red B and acidic black 234 dye can be arrived at 100%. 相似文献
10.
均相沉淀法合成纳米ZnO及其光催化性能研究 总被引:36,自引:0,他引:36
以ZnSO_4、尿素为原料,采用均相沉淀法在90 ℃合成出了纳米ZnO,并就反应 温度、反应时间、反应物浓度及物料配比等条件对产物的影响进行了探讨。XRD物 相分析,产物为六方晶系;TEM形貌观察,粒子基本为球形,平均粒径20 nm;并用 IR,TG-DTA等测试手段对其进行了表征。利用紫外-可见分光光度计测试了光吸收 性能,发现纳米氧化锌对200~380 nm波长范围的光有很强吸收性,在可见光范围 内,也有较强的吸收。利用纳米氧化锌作为光催化剂对有机染料溶液进行了降解实 验,发现在日光照射60 min后,对酸性大红4BE的降解率可达100%。 相似文献