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Super-hydrophobic surfaces have been fabricated by casting polydimethylsiloxane (PDMS) on a textured substrate of known surface topography, and were characterized using contact angle, atomic force microscopy, surface free energy calculations, and adhesion measurements. The resulting PDMS has a micro-textured surface with a static contact angle of 153.5° and a hysteresis of 27° when using de-ionized water. Unlike many super-hydrophobic materials, the textured PDMS is highly adhesive, allowing water drops as large as 25.0 μL to be inverted. This high adhesion, super-hydrophobic behavior is an illustration of the "petal effect". This rapid, reproducible technique has promising applications in transport and analysis of microvolume samples.  相似文献   
23.
This paper describes the operation and outcome of one of the United Kingdom's largest multi-partner research activities in nanoparticles.The research covers the discovery and development of organic and inorganic crystals/nanoparticles,nanoparticle properties towards specific product applications,The research also encompassed bespoke measurement technology for nanoparticles and structure interactions.Significant research outcomes are summarised.The paper illustrates the advantages from industrially motivated research and value of collective action between a broad group of researchers in a nation.  相似文献   
24.
Bose-Einstein correlations between pions of equal charge have been observed in Charged Current and Neutral Current (anti)neutrino-deuterium interactions in the BEBC bubble chamber exposed to the SPS wide band beam. The pion emission region is found to be essentially spherical with a mean radius of (0.48±0.07) fm; the chaoticity parameter is 0.36±0.04.  相似文献   
25.
The inclusive cross sections for η production by the interactions of 280 GeV/c momentum π?, π+, and proton beams in hydrogen have been measured. The kinematical range covered is ?0.45<x F <0.45, and 4.0<P T <7.0 GeV/c for Feynmanx F and transverse momentum respectively. The η to π0 cross section ratios are given for the three reactions. The ratio of π? p to π+ p cross sections for η production in the above kinematic ranges is 1.22±0.08±0.11.  相似文献   
26.
We analyse the proton electromagnetic form factor ratioR(Q 2 ) =QF 2 (Q 2 )/F 1 (Q 2 ) as a function of momentum transferQ 2 within perturbative QCD. We find that the prediction for (R(Q 2 ) at large momentum transferQ depends on the exclusive quark wave functions, which are unknown. For a wide range of wave functions we find thatQF 2 F 1 ~ const. at large momentum transfer, which is in agreement with recent JLAB data.  相似文献   
27.
The average multiplicities of charged hadrons and of π+, π? and π0 mesons, produced in \(\bar v\) Ne and νNe charged current interactions in the forward and backward hemispheres of theW ±-nucleon center of mass system, are studied with data from BEBC. The dependence of the multiplicities on the hadronic mass (W) and on the laboratory rapidity (y Lab) and the energy fraction (z) of the pion is also investigated. Special care is taken to determine the π0 multiplicity accurately. The ratio of average π multiplicities \(\frac{{2\left\langle {n_{\pi ^O } } \right\rangle }}{{[\left\langle {n_{\pi ^ + } } \right\rangle + \left\langle {n_{\pi ^ - } } \right\rangle ]}}\) is consistent with 1. In the backward hemisphere \(\left\langle {n_{\pi ^O } } \right\rangle \) is positively correlated with the charged multiplicity. This correlation, as well as differences in multiplicities between \(\mathop v\limits^{( - )} \) and \(\mathop v\limits^{( - )} \) , \(\mathop v\limits^{( - )} \) scattering, is attributed to reinteractions inside the neon nucleus of the hadrons produced in the initial \(\mathop v\limits^{( - )} \) interaction.  相似文献   
28.
The reactionppp f (K + K -π+π-)p s , where theK + K ? π+π- system is centrally produced, has been studied at 300 GeV/c. TheK *0 \(K^{*0} \bar K^{*0} \) final state has been observed and the cross sections for its central production are found to be the same at 300 and 85 GeV/c. TheK *0 \(K^{*0} \bar K^{*0} \) final state appears to be produced as a non-resonant threshold enhancement.  相似文献   
29.
The isoscalar nucleon structure functionsF 2(x, Q 2) andxF 3(x, Q 2) are measured in the range 0<Q 2<64 GeV2, 1.7<W 2<250 GeV2,x<0.7 using ν and \(\bar v\) interactions on neon in BEBC. The data are used to evaluate possible higher twist contributions and to determine their impact on the evaluation of the QCD parameter Λ. In contrast to previous analyses reaching to such lowW 2 values, it is found that a low \(\Lambda _{\overline {MS} } \) value in the neighbourhood of 100 MeV describes the data adequately and that the contribution of dynamical higher twist effects is small and negative.  相似文献   
30.
The reactions π+ p→π+(K + K ? π+ π? p andppp(K + K ? π+ π?)p where the (K + K ? π+ π?) system is centrally produced have been studied at 85 GeV/c. 48% of the final state proceeds through single or double vector meson resonant production i.e.,K *0(890) (37%), ? (4%),ρ 0 (7%). Evidence is found for associatedK *0 (890) \(\bar K\) *o (890) production (6.4±1.1%) with a cross section ten times higher than that found for associated ? ? production in the same experiment.  相似文献   
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