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31.
电沉积条件对锌镀层织构的影响 总被引:14,自引:1,他引:14
采用XRD方法研究添加剂,络合剂,以及电流密度对锌酸盐镀锌层的织构和晶粒尺寸的影响,结果表明,添加剂AA-1的存在有利于(101)晶面取向;而DIE则使镀层转变为110择优;两种添加剂同时存在下,可在一定的电流密度范围内获得高择优取向的锌镀层,而当又有络合剂TEA和EDTA同时存在时,则可在更宽广的电流密度范围内制得日 粒细密、表面光亮、择优系数TC(110)在985以上的高择优取向锌沉积层。 相似文献
32.
Styrene (St)-acrylic acid (AA) copolymer plates were synthesized in the frames made of glass, aluminum (Al) and poly(difluoroethylene) (PDFE). Surface properties of the prepared copolymer plates were characterized with regard to critical surface tension (
C
), chemical components by IR analysis and surface energies (total energy,
S
; dispersion force components,
S
d
; polar component,
S
p
; hydrogen bonding component,
S
h
) and the following results were obtained.The
C
values of the copolymer plates increased with AA content and also depended on the sort of the used frame. The increasing order of the
C
values of the copolymer plates corresponded to those of the used frames, namely, PDFE frame < Al frame < Glass frame.The prepared copolymer plates with low AA contents (ca. 10 mol%) were enriched in the AA moiety in the surface layer regardless of the kind of the used frame.The total and the individual components of the surface free energies of the copolymer plates were largely affected by the property of the used frame. The glass frame gave the plate with higher
S
h
values suggesting preferential orientation of the polar site of AA component. 相似文献
33.
A Dale-Eisinger style analysis (R. E. Daleet al., Biophys. J.
26, 161, 1979) is used to produce three-dimensional plots that display the limits on the average orientation factor k
2 that is required to calculate molecular distances in F-actin from fluorescence resonance energy transfer measurements. Maxima and minima plots are generated for the transfer of energy from a donor to a single acceptor and for transfer to multiple acceptors that are related by F-actin helical symmetry. The analysis is performed in terms of dipole cone half-angles rather than depolarization factors, in order to facilitate the modeling of the multiple acceptor problem. Calculations are carried out under the restrictive condition of a single electric dipole moment per fluorophore. In addition, both surface and volume averaging of the donor and acceptor dipoles are considered. Comparisons between the plots show that for the multiple acceptor cases with F-actin symmetry, there is a great reduction in the range for maxima and minima limits on k
2. The calculations also suggest guidelines for the choice of fluorescence label that will result in an average orientation factor occurring within acceptable limits, i.e., inside the limits for which k
2=2/3 may be employed. Thus, without having detailed knowledge of the mean donor or acceptor dipole relative orientations, the use of k
2=2/3 in radial coordinate studies of F-actin is more than reasonable and is fairly assured of being correct. 相似文献
34.
H.?Matsushima T.?Nohira Y.?ItoEmail author 《Journal of Solid State Electrochemistry》2004,8(3):195-200
The effects of a magnetic field (5 T) on crystal orientation and surface morphology were investigated for iron films electrodeposited in ferrous aqueous solution. XRD measurements for the iron films showed that the preferred orientation parallel to the substrate was determined by the current density and not influenced by the magnetic field. By X-ray pole figure measurements, however, the crystal texture of the iron films electrodeposited at 10 mA cm–2 and 30 mA cm–2 was found to be controlled by the magnetic field. That is, the (110) planes were orientated in same direction of the magnetic field vector at angles of 30° and 35° to the direction normal to the substrate plane at 10 mA cm–2 and 30 mA cm–2, respectively. When the morphology was observed by SEM, iron grains at 30 mA cm–2 changed from a triangular pyramid shape at 0 T to a complex star-like shape at 5 T.Presented at the 3rd International Symposium on Electrochemical Processing of Tailored Materials held at the 53rd Annual Meeting of the International Society of Electrochemistry, 15–20 September 2002, Düsseldorf, Germany 相似文献
35.
Dao-Dao Zhang Yao-Jun Sun Li-Shan Zhao Yong-Ming Huang 《Journal of inclusion phenomena and macrocyclic chemistry》1992,14(2):113-118
Inclusion complexes of 7,7-dibromonorcarane (1) and 7,7-dichloronorcarane (2) with 2,6-dimethyl--cyclodextrin (DMCD) have been synthesized. Their structures have been studied by chemical analysis, thermal behavior, IR spectra, UV absorptions and13C NMR spectra in DMSO solutions. The studies show that the orientation of (1) is different from that of (2) in the DMCD cavity.Presented at the 6th International Symposium on Molecular Recognition and Inclusion, Berlin, Germany, 10–14 September 1990. 相似文献
36.
Naoyuki Takahashi Arei Niwa Tadashi Takahashi Takato Nakamura 《Solid State Sciences》2003,5(11-12):1417-1419
The structural analysis of the hexagonal InN film prepared on a Si(100) substrate by the AP-HCVD technique using InCl3 and NH3 as starting materials were carried out by the X-ray pole figure analysis. The deposited films consist of the hexagonal InN pillar crystals. It was found that the pillar crystals, which have random rotation around the 100 axis, were grown at an angle of 70–90° to the substrate. 相似文献
37.
Small world effects in the harmonious unifying hybrid preferential model (HUHPM) networks are studied both numerically and analytically. The idea and method of the HUHPM is applied to three typical examples of unweighted BA model, weighted BBV model, and the TDE model, so-called HUHPM-BA, HUHPM-BBV and HUHPM-TDE networks. Comparing the HUHPM with current typical models above, it is found that the HUHPM networks has the smallest average path length and the biggest average clustering coefficient. The results demonstrate that the HUHPM is more suitable not only for the un-weighted models but also for the weighted models. 相似文献
38.
The orientation of antibodies, employed as capture molecules on biosensors, determines biorecognition efficiency and bioassay performance. In a previous publication we demonstrated for antibodies attached covalently to silicon that an increase in their surface amount Γ, evaluated with ellipsometry, induces changes in their orientation, which is traced directly using Time-of-Flight Secondary Ion Mass Spectroscopy combined with Principal Component Analysis. Here, we extend the above studies to antibodies adsorbed physically on a 3-aminopropyltriethoxysilane (APTES) monolayer. Antibodies physisorbed on APTES (0 ≤ Γ ≤ 3.5 mg/m2) reveal the Γ ranges for flat-on, side-on, and vertical orientation consistent with random molecular packing. The relation between orientation and Γ is juxtaposed for silicon functionalized with APTES, APTES modified with glutaraldehyde (APTES/GA) and N-hydroxysuccinimide-silane (NHS-silane). Antibody reorientation occurs at lower Γ values when physisorption (APTES) is involved rather than chemisorption (APTES/GA, NHS-silane). At high Γ values, comparable proportions of molecules adapting head-on and tail-on vertical alignment are concluded for APTES and the NHS-silane monolayer, and they are related to intermolecular dipole–dipole interactions. Intermolecular forces seem to be less decisive than covalent binding for antibodies on the APTES/GA surface, with dominant head-on orientation. Independently, the impact of glutaraldehyde activation of APTES on vertical orientation is confirmed by separate TOF-SIMS measurements. 相似文献
39.
40.
Licia Guzzella Fiorenzo Pozzoni Giuseppe Giuliano 《International journal of environmental analytical chemistry》2013,93(1):87-106
Abstract A field site equipped with suction cup lysimeters was installed at Treviglio (BG) to assess the migration capacity of the herbicides linuron and monolinuron from topsoil to groundwater and to verify the appearance of their relevant transformation products in soil and water samples. A constant hydraulic head was applied in order to develop water saturation conditions in the upper layers. KCl was used as a tracer to evaluate water infiltration velocity through the vertical soil profile. The constant hydraulic head accelerated infiltration rates, while herbicide concentrations reached maximum contamination because soil adsorption capacity was underdeveloped. The results indicated two main processes of pesticide transport: firstly transport due mainly to water infiltration through macropores; secondly the transport driven by matrix flow. Linuron was found to be the most mobile herbicide, while chloroanilines were found to be the major transformation products of the herbicides considered. 相似文献