A pneumatic droplet generator to produce water/glycerin droplets smaller than the nozzle diameter is described. The generator
consists of a T-junction with a nozzle fit into one opening, the second opening connected to a gas cylinder through a solenoid
valve and the third connected to a length of steel tubing. The droplet generator is filled with liquid. Opening the valve
for a preset time creates a pulse of alternating negative and positive pressure in the gas above the surface of the liquid,
ejecting a single droplet through the nozzle. Droplet formation was photographed and the pressure variation in the droplet
generator recorded. The effect of various experimental parameters, such as nozzle size, pressure pulse width and liquid properties
on droplet formation was investigated. Small droplets could not be generated when liquid viscosity was too low or too high.
For pure water, droplet diameters were several times that of the nozzle. Using more viscous glycerin mixtures, droplets with
diameters as small as 65% of the nozzle diameter could be produced. 相似文献
We observe production of a Ξ*(2370) in the reactions K?p→K, Kπ and [ΩK] (K or Kπ) at 8.25 GeV/c in a high statistics bubble chamber experiment. The mass and width are determined to be 2373 ± 8 MeV and 80 ± 25 MeV, respectively. The I = 1/2 assignment is strongly favoured. 相似文献
We present evidence for a narrow Y1 with a mass of 3.17 GeV and a width ? 20 MeV decaying to ΣKK? + pions, ΛKK? + pions and ΞK + pions. The data come from two high statistics K?p bubble chamber experiments with a sensitivity of ≈100 eV/μbat 8.25 GeV/c and ≈ 45 eV/μbat 6.5 GeV/c. 相似文献
Silica-supported zinc chloride (SiO2-ZnCl2) and novel alumina-supported sodium hydrogensulfate (NaHSO4-Al2O3) as recyclable heterogeneous catalysts have been used for the mild trimethylsilylation of hydroxyl groups under ambient conditions. This procedure also allows for the selective protection of primary and secondary alcohols in the presence of tertiary alcohols. 相似文献
A new, facile, and cost-effective process involving the solvent-free synthesis of amidoalkyl naphthols using a three-component, one-pot condensation reaction of β-naphthol, aromatic aldehyde, and amides in the presence of Al(H2PO4)3 as heterogeneous catalyst under thermal conditions and microwave irradiation has been described. This new approach has the advantage of consistently excellent yields and short reaction times. The catalyst has shown a very stable catalytic activity in the reaction conditions and also can be recovered and recycled. 相似文献
A highly efficient and mild procedure for the trimethylsilylation of a wide variety of alcohols, including primary, benzylic, secondary, hindered secondary, tertiary, phenols, and oximes with hexamethyldisilazane (HMDS) using alumina perchloric acid (Al2O3-HClO4) as recyclable heterogeneous catalyst in excellent yields with short reaction times (3?65 min) under ambient conditions is described. 相似文献
The quantum-dot cellular automata (QCA) were highly regarded due to its high operating frequency and significantly low power consumption. One of the most useful circuits in processors architecture is counter. This paper presents effective designs and arrangement of QCA based counter-circuits. In this study new counter circuits in QCA technology are designed and precise simulation are done using the QCADesigner. Three, four and five bits counters are proposed in this paper in QCA technology. A comparison is made between the past and recent designs to illustrate which method is better and more efficient in terms of area, complexity, number of cells, and delay. For example, the proposed three bit shift register has 174 quantum cells, 0.2μm2 occupied area and three QCA clock cycles delay.
In a high statistics bubble chamber experiment on K?p interactions at 8.25 , the study of the reaction K?p → KKΛ provides evidence for an enhancement in the KK system with a mass of (1850 ± 10) MeV and a width of (80?30+40) MeV. Its possible identification with the missing isosinglet of the 3? nonet is discussed. A K1 decay mode is also observed. 相似文献