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121.
The possible ways of compacitification of theE 8 E 8 Superstring theory to four dimensions are reviewed. The phenomenological need forN=1 supersymmetry is argued (on quite general grounds) to favour the choice of a Calabi-Yau manifold for the compact internal manifold. The massless spectrum after compactification is derived in full detail revealing, beside the usual particles, others that may have great phenomenological impact. The technical aspects of the construction of such manifolds are examined and the methods of calculation of the relevant topological properties are given. A big family of such constructions, giving rise to many new Calabi-Yau manifolds, is presented and its relevance to the search of a phenomenologically acceptable solution is discussed.This work was supported by the National Science Foundation  相似文献   
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Optical technologies in the long‐wave infrared (LWIR) spectrum (7–14 μm) offer important advantages for high‐resolution thermal imaging in near or complete darkness. The use of polymeric transmissive materials for IR imaging offers numerous cost and processing advantages but suffers from inferior optical properties in the LWIR spectrum. A major challenge in the design of LWIR‐transparent organic materials is that nearly all organic molecules absorb in this spectral window which lies within the so‐called IR‐fingerprint region. We report on a new molecular‐design approach to prepare high refractive index polymers with enhanced LWIR transparency. Computational methods were used to accelerate the design of novel molecules and polymers. Using this approach, we have prepared chalcogenide hybrid inorganic/organic polymers (CHIPs) with enhanced LWIR transparency and thermomechanical properties via inverse vulcanization of elemental sulfur with new organic co‐monomers.  相似文献   
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This study focused on fundamental data acquisition parameter selection for a benchtop nuclear magnetic resonance (NMR) system with continuous flow, applicable for reaction monitoring. The effect of flow rate on the mixing behaviors within a flow cell was observed, along with an exponential decay relationship between flow rate and the apparent spin–lattice relaxation time (T1*) of benzaldehyde. We also monitored sensitivity (as determined by signal-to-noise ratios; SNRs) under various flow rates, analyte concentrations, and temperatures of the analyte flask. Results suggest that a maximum SNR can be achieved with low to medium flow rates and higher analyte concentrations. This was consistent with data collected with parameters that promote either slow or fast data acquisition. We further consider the effect of these conditions on the analyte's residence time, T1*, and magnetic field inhomogeneity that is a product of continuous flow. Altogether, our results demonstrate how fundamental acquisition parameters can be manipulated to achieve optimal data acquisition in continuous-flow NMR systems.  相似文献   
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Amphiphilic ABA triblock copolymers, such as poly(2-methyloxazoline)-block-poly(dimethylsiloxan)-block-poly(2-methyloxazoline) (PMOXA-PDMS-PMOXA), form vesicular structures. Here, the interaction of these ABA molecules with lipids is investigated by electron microscopy, fluorescence spectroscopy, light scattering, and differential scanning calorimetry. Our observations suggest the formation of homogeneous mixed polymer-lipid composites, independent of preparation method, i.e. film hydration, dispersion, or detergent removal. When ABA polymersomes and liposomes are mixed, we observed monomer exchanges on a time scale of minutes. The possibility of forming mixed structures and the exchanges between preformed structures allow the combination of the properties of lipids and polymers such as stability and loading encapsulation capacity.  相似文献   
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** Email: tbarnett{at}swin.edu.au*** Email: sclarke{at}swin.edu.au With the growth in sports betting, it is possible to bet, bothbefore and during a match, on a range of outcomes in tennis.This paper shows how the standard statistics published by theATP can be combined to predict the serving statistics to beobtained when two given players meet. These statistics are thenused in a spreadsheet model to predict further match outcomes,such as the length of the match and chance of either playerwinning. These calculations can be updated as the match progresses.The method is demonstrated by focusing on a very long men'ssingles match between Roddick and El Aynaoui played at the 2003Australian Open.  相似文献   
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We have developed a digital holographic microscope (DHM), in a transmission mode, especially dedicated to the quantitative visualization of phase objects such as living cells. The method is based on an original numerical algorithm presented in detail elsewhere [Cuche et al., Appl. Opt. 38, 6994 (1999)]. DHM images of living cells in culture are shown for what is to our knowledge the first time. They represent the distribution of the optical path length over the cell, which has been measured with subwavelength accuracy. These DHM images are compared with those obtained by use of the widely used phase contrast and Nomarski differential interference contrast techniques.  相似文献   
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Tristan Barnett 《CHANCE》2009,22(3):27-34
Scenarios 1 and 2 assume the player only plays the one game to turn over the required 10,000. If a player had a good run in the first10,000. If a player had a good run in the first 5,000 turnover in Casino War, he or she may be inclined to switch to 3 Card Stud Poker. Likewise, if a player had a bad run in the first $5,000 turnover in 3 Card Stud Poker, he or she may be inclined to switch to Casino War. A player’s choice to switch between 3 Card Stud Poker and Casino War is dependent on his or her current bankroll and how many hands are left to play to wager the required $5,000 turnover in 3 Card Stud Poker, he or she may be inclined to switch to Casino War. A player’s choice to switch between 3 Card Stud Poker and Casino War is dependent on his or her current bankroll and how many hands are left to play to wager the required 10,000. The minimum bet for both games has always been applied. A player may choose to speed up the process by betting higher than the minimum. This may again depend on the player’s current bankroll and how many hands are left to play. In general, increasing the size of the bankroll in any casino game increases the variance and skewness. This would amount to increasing the probability of losing the initial 200 before wagering the initial200 before wagering the initial 5,000 (i.e., a greater chance of having to deposit more money into the casino account).  相似文献   
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