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101.
Operational characteristics of a dual gain single cavity Nd:YVO4 laser have been investigated. With semiconductor diode laser pump power of 2 W, 800 mW output was obtained with a slope efficiency
of 49%. Further, by changing the relative orientation of the two crystals the polarization characteristics of the output could
be varied. In particular by keeping the two Nd:YVO4 crystals with their c-axes orthogonal to each other and adjusting the gain of the crystals so that both operate at approximately the same power
level, completely unpolarized beams could be obtained. 相似文献
102.
(张泽银)(王建忠)ONNECESSARYANDSUFFICIENTCONDITIONSFORDUALSOFWAVELETFRAMES¥ZhangZeyin(Dept.ofMath.,HubaiUniversity,Wuhan430062,China... 相似文献
103.
104.
Hiroaki Taniguchi 《Graphs and Combinatorics》2007,23(4):455-465
Let q = 2l with l≥ 1 and d ≥ 2. We prove that any automorphism of the d-dimensional dual hyperoval
over GF(q), constructed in [3] for any (d + 1)-dimensional GF(q)-vector subspace V in GF(qn) with n≥ d + 1 and for any generator σ of the Galois group of GF(qn) over GF(q), always fixes the special member X(∞). Moreover, we prove that, in case V = GF(qd+1), two dual hyperovals
and
in PG(2d + 1,q), where σ and τ are generators of the Galois group of GF(qd+1) over GF(q), are isomorphic if and only if (1) σ = τ or (2) σ τ = id. Therefore, we have proved that, even in the case q > 2, there exist non isomorphic d-dimensional dual hyperovals in PG(2d + 1,q) for d ≥ 3. 相似文献
105.
Ultrasound has been proven to enhance the mass transfer process and impact the fabrication of anodic aluminum oxide (AAO). However, the different effects of ultrasound propagating in different media make the specific target and process of ultrasound in AAO remain unclear, and the effects of ultrasound on AAO reported in previous studies are contradictory. These uncertainties have greatly limited the application of ultrasonic-assisted anodization (UAA) in practice. In this study, the bubble desorption and mass transfer enhancement effects were decoupled based on an anodizing system with focused ultrasound, such that the dual effects of ultrasound on different targets were distinguished. The results showed that ultrasound has the dual effects on AAO fabrication. Specifically, ultrasound focused on the anode has a nanopore-expansion effect on AAO, leading to a 12.24 % improvement in fabrication efficiency. This was attributed to the promotion of interfacial ion migration through ultrasonic-induced high-frequency vibrational bubble desorption. However, AAO nanopores were observed to shrink when ultrasound was focused on the electrolyte, accompanied by a 25.85 % reduction in fabrication efficiency. The effects of ultrasound on mass transfer through jet cavitation appeared to be the reason for this phenomenon. This study resolved the paradoxical phenomena of UAA in previous studies and is expected to guide AAO application in electrochemistry and surface treatments. 相似文献
106.
In this paper, the behavior of an interface crack for a functionally graded strip sandwiched between two homogeneous layers
of finite thickness subjected to an uniform tension is resolved using a somewhat different approach, named the Schmidt method.
The Fourier transform technique is applied and a mixed boundary value problem is reduced to two pairs of dual integral equations
in which the unknown variables are the jumps of the displacements across the crack surface. To solve the dual integral equations,
the jumps of the displacements across the crack surfaces are expanded in a series of Jacobi polynomials. This process is quite
different from those adopted in previous works. Numerical examples are provided to show the effects of the crack length, the
thickness of the material layer and the materials constants upon the stress intensity factor of the cracks. It can be obtained
that the results of the present paper are the same as ones of the same problem that was solved by the singular integral equation
method. As a special case, when the material properties are not continuous through the crack line, an approximate solution
of the interface crack problem is also given under the assumption that the effect of the crack surface interference very near
the crack tips is negligible. Contrary to the previous solution of the interface crack, it is found that the stress singularities
of the present interface crack solution are the same as ones of the ordinary crack in homogenous materials. 相似文献
107.
Enantiomeric separation of 1,3‐dimethylamylamine by capillary electrophoresis with indirect UV detection using a dual‐selector system
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The CE method employing an indirect UV detection for the enantioseparation of 1,3‐dimethylamylamine (DMAA), widely used in various preworkout and dietary supplements labeled as a constituent of geranium extract has been developed. The dual‐selector system consisting of negatively charged sulfated α‐CD (1.1% w/v) and sulfated β‐CD (0.2% w/v) in 5 mM phosphate/Tris buffer (pH 3.0) containing the addition of 10 mM benzyltriethylammonium chloride (BTEAC) as the chromophoric additive was used for the enantiomeric separation of DMAA stereoisomers with the LODs in the range of 7.82–9.24 μg/mL. The method was partly validated and applied for the determination of the stereoisomeric composition of DMAA in commercial dietary supplements to verify the potential natural origin of DMAA. 相似文献
108.
A typical, reproducible, and rugged screen printed carbon electrode, modified with dual-ion imprinted beads, was fabricated employing the “surface grafting from” approach. For this, the acyl chloride functionalized magnetic nanoparticles were first immobilized and chemically attached with a typical functional monomer (but-2-enedioic acid bis-[(2-amino-ethyl)-amide]) on the electrode surface. This was subsequently subjected to the thermal polymerization in the presence of template ions (Ce(IV) and Gd(III)), cross-linker (ethylene glycol dimethacrylate), initiator (AIBN), and multiwalled carbon nanotubes. The modified sensor was used for the simultaneous analysis of both template ions in aqueous, blood serum, and waste-water samples, using differential pulse anodic stripping voltammetry which revealed two oxidation peaks for respective templates with resolution as much as 950 mV, without any cross reactivity, interferences and false-positives. The detection limits realized by the proposed sensor, under optimized conditions, were found to be as low as 0.07 ng mL−1 for Ce(IV) and 0.19 ng mL−1 for Gd(III) (S/N = 3) that could eventually be helpful for lanthanide estimation at stringent levels. 相似文献
109.
Minghui Chen Zhibiao Yu Daofeng Liu Tao Peng Kun Liu Shuying Wang Yonghua Xiong Hua Wei Hengyi Xu Weihua Lai 《Analytica chimica acta》2015
Two patterns of signal amplification lateral flow immunoassay (LFIA), which used anti-mouse secondary antibody-linked gold nanoparticle (AuNP) for dual AuNP-LFIA were developed. Escherichia coli O157:H7 was selected as the model analyte. In the signal amplification direct LFIA method, anti-mouse secondary antibody-linked AuNP (anti-mouse-Ab-AuNP) was mixed with sample solution in an ELISA well, after which it was added to LFIA, which already contained anti-E. coli O157:H7 monoclonal antibody-AuNP (anti-E. coli O157:H7-mAb-AuNP) dispersed in the conjugate pad. Polyclonal antibody was the test line, and anti-mouse secondary antibody was the control line in nitrocellulose (NC) membrane. In the signal amplification indirect LFIA method, anti-mouse-Ab-AuNP was mixed with sample solution and anti-E. coli O157:H7-mAb-AuNP complex in ELISA well, creating a dual AuNP complex. This complex was added to LFIA, which had a polyclonal antibody as the test line and secondary antibody as the control line in NC membrane. The detection sensitivity of both LFIAs improved 100-fold and reached 1.14 × 103 CFU mL−1. The 28 nm and 45 nm AuNPs were demonstrated to be the optimal dual AuNP pairs. Signal amplification LFIA was perfectly applied to the detection of milk samples with E. coli O157:H7 via naked eye observation. 相似文献
110.
In this work, a novel sandwich-type electrochemical immunosensor based on host-guest interaction was fabricated for the detection of alpha-fetoprotein (AFP). Due to the large specific surface area of multiwalled carbon nanotubes and the unique supramolecular recognition ability of β-cyclodextrins, ferrocenecarboxylic acid (Fc) was incorporated into this sensor platform by host-guest interaction to generate an electrochemical signal. And β-cyclodextrins functionalized silver supported adamantine-modified glucose oxidase (GOD-CD-Ag), was used as a label to improve the analytical performance of the immunosensor by the dual amplification strategy. The obtained GOD-CD-Ag conjugates could convert glucose into gluconic acid with the formation of hydrogen peroxide (H2O2). And then silver nanoparticles could in situ catalyze the reduction of the generated H2O2, dramatically improving the oxidation reaction of Fc. The developed immunosensor shows a wide linear calibration range from 0.001 to 5.0 ng/mL with a low detection limit (0.2 pg/mL) for the detection of AFP. The method, with ideal reproducibility and selectivity, has a wide application prospect in clinical research. 相似文献