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141.
142.
Ca3MgNi14, Nd1.5Ca1.5MgNi14, Gd1.5Ca1.5MgNi14 and Er1.5Ca1.5MgNi14 alloys were prepared by high frequency induction melting and sintering. Characterization and analysis were performed by X-ray diffraction/Rietveld full-spectrum fitting, gaseous P-C-T hydrogen storage test and electrochemical properties tests. It can be found that all alloys consist of Gd2Co7-type 3R phase and Ce2Ni7-type 2H phase. Although the hydrogen storage capacities of Nd1.5Ca1.5MgNi14, Gd1.5Ca1.5MgNi14 and Er1.5Ca1.5MgNi14 decrease to some extent compared to that of Ca3MgNi14, their equilibrium pressures for absorption and desorption increase markedly. Moreover, R1.5Ca1.5MgNi14 alloys have better cycling stabilities and high-rate discharge(HRD) properties as compared to Ca3MgNi14. The hydrogen diffusion in alloy electrodes is the main factor to influence the HRD performance. 相似文献
143.
利用Ar/CF4、Ar/CF2Cl2或Ar/CF3COOH混合气体的直流脉冲放电产生CF自由基,观测了260~360nm范围内转动分辨的CF自由基双光子共振增强多光子电离谱。分析表明,该段光 谱对应于CF自由基3pπD2Πr(ν'=2~6,r=3/2,1/2)←←X2Πr(ν"=0,r=3/2,1/2)的共振激发。对观测的振动带进行了转动分析,并获得了3p里德堡态的转动常数和自旋-轨道分裂值。 相似文献
144.
DC cathodic polymerization of trimethylsilane (TMS) was carried out in plasma reactors with and without using anode assembly. In DC cathodic polymerization, the TMS plasma polymers are mainly deposited on the cathode (substrate) surface. As a result, fast deposition of TMS plasma polymers was easily achieved in DC cathodic polymerization as compared with AF or RF plasma polymerization. DC cathodic polymerization without using anode assembly has its advantageous features that the size and number of substrates (as cathodes) are not restricted by the size and the location of anode assembly. It was found that the maximum deposition rate on the cathode surfaces was obtained without anode assembly. The DC cathodic polymerization of TMS was conducted also in a large volume reactor with multiple cathodes (substrates). The same deposition mechanisms for DC cathodic polymerization with a single cathode also apply to the multiple cathodes. Uniform deposition on each cathode could be obtained with appropriate spacing of multiple cathodes and by adjusting the operational parameters, which are based on the current density and the system pressure. 相似文献
145.
采用发射光谱法,研究了水电极介质阻挡放电中具有相同对称性的3种不同结构的六边形斑图演化过程的光谱特性。实验结果表明,随着外加电压的增加,放电首先形成六边形点阵斑图,然后是空心六边形斑图,最后是蜂窝六边形斑图。利用氩原子696.5 nm(2P_2→1S_5)谱线的展宽、氩原子763.2 nm(2P_6→1S_5)与772.1 nm(2P_2→1S_3)两条谱线强度比法和氮分子第二正带系(C~3Π_u→B~3Π_g)的发射谱线,研究上述3种斑图的电子密度、电子激发温度及分子振动温度。结果发现,随着外加电压的升高,六边形点阵斑图、空心六边形斑图和蜂窝六边形斑图的电子密度逐渐减小,而电子激发温度和分子振动温度逐渐增加。等离子体状态的改变直接影响着斑图的自组织。 相似文献
146.
采用辉光放电聚合技术,在不同工作压强条件下在直径为350—400 μm,厚度为2.5—3 μm的玻璃微球上制备了辉光放电聚合物 (GDP)涂层,并对玻璃/GDP微球模拟充气过程进行了热稳定性实验.利用傅里叶变换红外光谱仪、元素分析仪、热重法、体视显微镜和X射线照相技术对GDP涂层的内部结构及其化学键、热稳定性、微球形貌和厚度进行了表征.结果表明:GDP涂层中的碳氢比、不饱和键和C C含量随着制备压强的增大而减小,低压的热稳定性较好,GDP涂层与玻璃微球的结合力提高,流变、起泡和脱层现象也得到明显改善.微球
关键词:
玻璃微球
GDP涂层
热稳定性
结合力 相似文献
147.
Gabriela Petroselli Mridul Kanti Mandal Lee Chuin Chen Gustavo T. Ruiz Ezequiel Wolcan Kenzo Hiraoka Hiroshi Nonami Rosa Erra‐Balsells 《Journal of mass spectrometry : JMS》2012,47(3):313-321
A group of rhenium (I) complexes including in their structure ligands such as CF3SO3‐, CH3CO2‐, CO, 2,2′‐bipyridine, dipyridil[3,2‐a:2′3′‐c]phenazine, naphthalene‐2‐carboxylate, anthracene‐9‐carboxylate, pyrene‐1‐carboxylate and 1,10‐phenanthroline have been studied for the first time by mass spectrometry. The probe electrospray ionization (PESI) is a technique based on electrospray ionization (ESI) that generates electrospray from the tip of a solid metal needle. In this work, mass spectra for organometallic complexes obtained by PESI were compared with those obtained by classical ESI and high flow rate electrospray ionization assisted by corona discharge (HF‐ESI‐CD), an ideal method to avoid decomposition of the complexes and to induce their oxidation to yield intact molecular cation radicals in gas state [M]+. and to produce their reduction yielding the gas species [M]–.. It was found that both techniques showed in general the intact molecular ions of the organometallics studied and provided additional structure characteristic diagnostic fragments. As the rhenium complexes studied in the present work showed strong absorption in the UV–visible region, particularly at 355 nm, laser desorption ionization (LDI) mass spectrometry experiments could be conducted. Although intact molecular ions could be detected in a few cases, LDI mass spectra showed diagnostic fragments for characterization of the complexes structure. Furthermore, matrix‐assisted laser desorption ionization (MALDI) mass spectra were obtained. Nor‐harmane, a compound with basic character, was used as matrix, and the intact molecular ions were detected in two examples, in negative ion mode as the [M]–. species. Results obtained with 2‐[(2E)‐3‐(4‐tert‐buthylphenyl)‐2‐methylprop‐2‐enylidene] malononitrile (DCTB) as matrix are also described. LDI experiments provided more information about the rhenium complex structures than did the MALDI ones. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
148.
149.
Schmidt-Szalowski K. Rżanek-Boroch Z. Sentek J. Rymuza Z. Kusznierewicz Z. Misiak M. 《Plasmas and Polymers》2000,5(3-4):173-190
Hexamethyldisiloxane (HMDSO) and hexamethyldisilazane (HMDSN) were used as organosilicon reagents for PE-CVD of thin films under filamentary barrier-discharge conditions at atmospheric pressure. Efficient discharges were obtained in the region of moderate frequencies (5 kHz). The following mixtures of organosilicon reagents with carrier gas and oxidants or ammonia were investigated: HMDSO+Ar, HMDSO+N2, HMDSO+O2+Ar, HMDSO+N2O+Ar, and HMDSN+NH3+N2. Under such conditions HMDSO was converted to produce thin films (10–1000 nm) of silicon oxide, generally containing admixtures of residual organic content (Si—CHn and Si—H groups). The films deposited from HMDSN+NH3+N2 contained silicon, nitrogen and oxygen. 相似文献
150.
采用侧面紫外火花隙自动预电离代替小极上小孔预电离,使放电泵浦氟化氪激光器的主放电均匀性大为改善。输出激光能量由140mJ提高到250mJ,增益区光能密度为2.3J/1,同时电极寿命和气体寿命也大为提高。 相似文献