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91.
Photo-lithographically impregnated and molecularly imprinted polymer thin film for biosensor applications 总被引:1,自引:0,他引:1
A voltammetric sensor for albuterol was investigated where we combined the techniques of microfabrication and molecular imprinting to construct on-chip devices using photoirradiation of cross-linkable polymers. Molecularly imprinted polymer was coated as a thin film onto the gold working electrode on chip and the analyte was directly quantified by differential pulse voltammetric measurements. 相似文献
92.
Measurement of filament length generated by an intense femtosecond laser pulse using electromagnetic radiation detection 总被引:4,自引:0,他引:4
We present a new method to measure the length of a filament induced by the propagation of intense femtosecond laser pulses
in air. We used an antenna to detect electromagnetic pulses radiated from multipole moments inside the filament oscillating
at the plasma frequency. The results are compared with the values detected from the backscattered fluorescence induced by
multiphoton ionization of nitrogen molecules excited inside the filament. The values are found to be in good agreement.
Received: 6 November 2002 / Revised version: 27 January 2003 / Published online: 24 April 2003
RID="*"
ID="*"Corresponding author. Fax: +1-418/656-2623, E-mail: shosseini@phy.ulaval.ca 相似文献
93.
The backscattered fluorescence of nitrogen from filaments generated by intense ultra-fast Ti:sapphire laser pulses propagating
in air is studied. The backscattered fluorescence from N2 molecules and ions show an exponential increase with increasing filament length, indicating amplified spontaneous emission.
Received: 11 October 2002 / Revised version: 3 December 2002 / Published online: 26 February 2003
RID="*"
ID="*"Corresponding author. Fax: +1-418/6562-623, E-mail: qluo@phy.ulaval.ca 相似文献
94.
Chin CL Wehrli FW Hwang SN Jaggard DL Hackney DB Wehrli SW 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,160(1):20-25
It is well known that one-dimensional (1D) q-space imaging allows retrieval of structural information at cellular resolution. Here we demonstrate by simulation that boundary morphology of structured materials can be derived from 2D q-space mapping. Based on a finite-difference model for restricted diffusion, 2D q-space maps obtained from water diffusion inside apertures at various levels of asperity were simulated. The results indicate that the observed ring patterns (diffraction minima) reveal the boundary profiles of the apertures but become blurred in the case of significant variation in aperture size. For uniform size distribution of apertures, a quantitative measure of surface roughness can be established by means of spatial autocorrelation analysis. The results suggest that 2D q-space imaging may allow probing of the boundary morphology of structured materials and possibly biological cells. 相似文献
95.
96.
CheeWhye Chin 《Advances in Mathematics》2003,180(1):64-86
Let X be a smooth curve over a finite field of characteristic p, let ?≠p be a prime number, and let be an irreducible lisse -sheaf on X whose determinant is of finite order. By a theorem of L. Lafforgue, for each prime number ?′≠p, there exists an irreducible lisse -sheaf on X which is compatible with , in the sense that at every closed point x of X, the characteristic polynomials of Frobenius at x for and are equal. We prove an “independence of ?” assertion on the fields of definition of these irreducible ?′-adic sheaves : namely, that there exists a number field F such that for any prime number ?′≠p, the -sheaf above is defined over the completion of F at one of its ?′-adic places. 相似文献
97.
Joannie Chin Amanda Forster Lipiin Sung Kirk Rice 《Polymer Degradation and Stability》2007,92(7):1234-1246
In recent years, poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers have become prominent in high strength applications such as body armor, ropes and cables, and recreational equipment. The objectives of this study were to expose woven PBO body armor panels to elevated temperature and moisture, and to analyze the chemical, morphological and mechanical changes in PBO yarns extracted from the panels. A 30% decrease in yarn tensile strength, which was correlated to changes in the infrared peak absorbance of key functional groups in the PBO structure, was observed during the 26 week elevated temperature/elevated moisture aging period. Substantial changes in chemical structure were observed via infrared spectroscopy, as well as changes in polymer morphology using microscopy and neutron scattering. When the panels were removed to an ultra-dry environment for storage for 47 weeks, no further decreases in tensile strength degradation were observed. In a follow-on study, fibers were sealed in argon-filled glass tubes and exposed to elevated temperature; less than a 4% decrease in tensile strength was observed after 30 weeks, demonstrating that moisture is a key factor in the degradation of these fibers. 相似文献
98.
High Performance Nonvolatile Transistor Memories Utilizing Functional Polyimide‐Based Supramolecular Electrets 下载免费PDF全文
Wei‐Yao Tung Meng‐Hsien Li Dr. Hung‐Chin Wu Hsin‐Yu Liu Yun‐Ting Hsieh Prof. Wen‐Chang Chen 《化学:亚洲杂志》2016,11(10):1631-1640
We report pentacene‐based organic field‐effect transistor memory devices utilizing supramolecular electrets, consisting of a polyimide, PI(6FOH‐ODPA), containing hydroxyl groups for hydrogen bonding with amine functionalized aromatic rings (AM) of 1‐aniline (AM1), 2‐naphthylamine (AM2), 2‐aminoanthracene (AM3), and 1‐aminopyrene (AM4). The effect of the phenyl ring size and composition of AM1–AM4 on the hole‐trapping capability of the fabricated devices was investigated systematically. Under an operating voltage under ±40 V, the prepared devices using the electrets of 100 % AM1–AM4/PI ratios exhibited a memory window of 0, 8.59, 25.97, and 29.95 V, respectively, suggesting that the hole‐trapping capability increased with enhancing phenyl ring size. The memory window was enhanced as the amount of AM in PI increased. Furthermore, the devices showed a long charge‐retention time of 104 s with an ON/OFF current ratio of around 103–104 and multiple switching stability over 100 cycles. This study demonstrated that the electrical characteristics of the OFET memory devices could be manipulated through the chemical compositions of the supramolecular electrets. 相似文献
99.
<正>With the evolution of a laser pulse in water,the formation of a nonlinear X wave during femtosecond filamentation is investigated based on numerical simulations.In particular,we analyze the far-field angularly resolved spectra obtained for different temporal portions of the ultrashort pulse during its propagation. Our result shows that the refocusing of ultrashort pulse leads to the formation of dynamic X wave which essentially manifests itself as conical emission. 相似文献
100.
Bartenstein M Altmeyer A Riedl S Geursen R Jochim S Chin C Denschlag JH Grimm R Simoni A Tiesinga E Williams CJ Julienne PS 《Physical review letters》2005,94(10):103201
We employ radio-frequency spectroscopy on weakly bound (6)Li(2) molecules to precisely determine the molecular binding energies and the energy splittings between molecular states for different magnetic fields. These measurements allow us to extract the interaction parameters of ultracold (6)Li atoms based on a multichannel quantum scattering model. We determine the singlet and triplet scattering lengths to be a(s) = 45.167(8)a(0) and a(t) = -2140(18)a(0) (1a(0) = 0.052 917 7 nm), and the positions of the broad Feshbach resonances in the energetically lowest three s-wave scattering channels to be 83.41(15), 69.04(5), and 81.12(10) mT. 相似文献