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本文研究了Hilbert空间中的有效序列,通过引入序列的伴随序列,给出了有效序列的一个等价刻画,接着讨论了保持向量序列有效性的线性算子的性质,证明了一个线性算子将任意有效序列映射为有效序列当且仅当它是酉算子;最后,给出了正规正交基中添加一个单位向量后所得到的序列是有效序列的一个充要条件. 相似文献
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Kinetics and Mechanism of the Thermal Decomposition Reaction of 3,3-Bis(azidomethyl)oxetane/Tetrahydrofuran Copolymer 总被引:1,自引:0,他引:1
Introduction 3,3-Bis(azidomethyl)oxetane/tetrahydrofuran (BAM- O/THF, marked as B/T) copolymer can be used as an azide binder of high energy propellants with the lower signature, and lower sensitivity to improve the me-chanical properties at lower temperature and the burning rate characteristics. Its decomposition kinetics and the effects of THF on the decomposition kinetics of BAMO copolymers have been reported.1,2 In the present work, we report the kinetic model function and kinetic pa… 相似文献
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With insulin methanol-water,and the ion-pairing agent,hydrochloric acid and trifluroacetic acid(TEA),the character of the first plateau(FP)on the elution curve of frontal analysis in reversed phase liquid chromatography(RPLC)was investigated by on-line UV-spectrometry and identified with nuclear magnetic resonance(NMR) spectrometry and mass spectrometry.The profile of the FP is the same as that of a usual elution curve of methanol in frontal analysis(FA).When the insulin concentration was limited to a certain range,the height of the FP was found to be proportional to the insulin concentration in mobile phase and its length companying to shorten,The FP profile on the intersection of two tangents reflects the components of the microstructure in the depth direction of the bonded stationary phase layer and the desorption dynamics of the displaced components.The displaced methanol was quantitatively determined by NMR and on-line UV spectrometries.TFA with high UV absorbance can not be used as an ionpairing agent for the investigation of the FP in RPLC,but if can be used as a good marker to investigate the complicated transfer process of components in the stationary phase in RPLC.A stoichiometric displacement process between solute and solvent was proved to be valid in both usual and FA in RPLC.From the point of view of dynamics of mass transfer, the solutes can only contact to the surface of stationary phase in usual RPLC,while solute can penetrate into it in FA of RPLC.The solvation of insulin in methanol and water solution as an example indicating the usage of the FP in the FA was also investigated in this paper. 相似文献
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Introduction3 Nitro 1,2 ,4 triazol 5 one (NTO)metalcomplexeshavemanyspecialstructuresandsomepotentialusesinammunition .1 4 Wepreviouslypreparedanddeterminedthecrystalstructureofitsmagnesiumcomplex ,5andinthispaper ,wediscusseditsthermalbehaviorbyDSCandTG/DTGtechniquesandstudieditsnon isothermalkineticsbythemeansoftheKissingermethod ,theOzawamethod ,thedifferentialmethodandtheintegralmethod .ExperimentalSample[Mg(H2 O) 6 ](NTO) 2 ·2H2 Owaspreparedasfollows :AcalculatedamountofMg(OH… 相似文献
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研究了在酸性镀铜溶液中添加不同分子量的PEG对直径为50微米、深径比为1的镀层盲孔填充效果的影响.结果表明,随着PEG分子量的增加,电镀铜溶液的微孔填充力明显提高.电流密度为2 A/dm2,添加剂PEG分子量(u)超过6000时,镀液可以完全填充盲孔,镀层不出现任何空洞和缝隙.这是由于添加剂PEG能明显加强电镀铜镀液阴极极化,抑制了电镀铜的沉积.同时,PEG于镀液中的扩散系数还随其分子量的增加而降低,从而增加了SPS在微孔底部的吸附力,加速了电镀铜在微孔底部的沉积.进一步,增大PEG分子量,沉积铜膜的表面粗糙度、铜膜结晶度和电阻率均有所降低. 相似文献
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3×3上三角算子矩阵的Weyl型定理 总被引:1,自引:0,他引:1
设A∈B(H1),B∈B(H2),C∈B(H3)为给定的三个算子,用M(D,E,F)= 表示一个作用在H1(?)H2(?)H3上的3×3算子矩阵.本文首先给出存在算子D∈B(H2,H1),E∈B(H3,H1),F∈B(H3,H2),使得M(D,E,F)为上半Fredholm算子(下半Fredholm算子)的充要条件.同时研究了3×3算子矩阵 M(D,E,F)的Weyl定理,α-Weyl定理,Browder定理和α-Browder定理. 相似文献
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高组份Al值的AlxGa1-x As和AlxGa1-x As/GaAs/AlxGa1-xAs/GaAs多层结构的MOCVD生长 总被引:1,自引:1,他引:0
用自制常压MOCVD系统,在半绝缘GaAs衬底上生长高Al组份AlxGa1-xAs(其x值达0.83),和AlxGa1-xAs/GaAs/AlxGa1-xAs/GaAs多层结构,表面镜面光亮。生长层厚度从几十到十几μm可控,测试表明外延层晶格结构完整,x值调节范围宽,非有意掺杂低,高纯GaAs外延层载流子浓度n300K=1.7×1015cm-3,n77K=1.4×1015cm-3,迁移率μ300K=5900cmcm2/V.S,μ77K=55500cm2/V.S。用电子探针,俄歇能谱仪测不出非有意掺杂的杂质,各层间界面清晰平直。 对GaAs,AlGaAs生长层表面缺陷,衬底偏角生长温度及其它生长条件也进行了初步探讨。 相似文献
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CCD电视系统实时位置测量的误差分析 总被引:2,自引:2,他引:0
本文就CCD电视摄像机对运动物体目标瞬时位置测量精度的几个问题进行讨论。文章首先分析了由于CCD成象器件结构特征和电子热噪音对目标位置测量精度的影响,给出位置测量误差与电视测量系统量化等级的关系,提出在保证一定测量精度下量化等级的选择原则。文章还分析了用普通电视摄象机组成的电视经纬仪测量运动目标位置的局限性,提出为获得较高的测量精度,选用高帧频电视摄象机的必要性。 相似文献