Super allowed

The final state nucleus (deuterium in its ground state) in the reaction p + p —> d + e+ + z/e, has JJ = 1 +, with a predominant relative orbital angular momentum If = 0 and Sf = 1 (triplet S-state). For a maximally probable super-allowed transition, there is no change in the orbital angular momentum between the initial and final states of the nuclei. Hence for such transitions, the initial state two protons in the p + p reaction must have /j = 0. Since the protons are identical particles, Pauli principle requires S) = 0, so that the total wave-function will be antisymmetric in space and spin coordinates. Thus, we have a process Si = 0, Z = 0 >—>, S y- 1,/y- 0 >. This is a pure Gamow-... 

Part the bees from their honey by placing an extra crown board, fitted with a bee escape, between the brood box and the super (where the honey is). This allows the bees to go into the brood chamber (where the queen lays her eggs), but not to return to the super. Allow at least 24 hours to clear a hive by the next day, the majority of your bees will be safe in the brood chamber. 

The levels of Si " are not known the ground state shows the normal super-allowed transition to AP. The bound levels of this nucleus have been very fully... 

CP has been produced by the pn) reaction [46] and from the threshold energy the first T = state in should be between 7 and 8 MeV. The gamma radiation observed in the decay of CP can be accounted for by transitions between known levels of including the T = level. The ft value for the beta-decay to this level would be that of a super-allowed transition, whereas the ft value for the transition to the 2.25 MeV 2 level is that of an ordinary allowed transition. The mirror transition of P iq this level is energetically forbidden and the P — ground state transition seems to be specially hindered because of the configuration change dzj should be weak decay... 

Asymmetric simhaiity measures allow fuzzy super- and substructure searching. A substructure search is defined as looking for structures containing the given query and a superstructure search is defined as looking for structures embedded in the given query. In both cases asymmetric local similarity is estimated. 

If, however, the sodium hydroxide is removed by allowing it to react with excess of an ester of high boiling point, such as ethyl succinate or ethyl phthalate, super-dry ethyl alcohol may be obtained ... 

Equip a 3 litre three-necked flask with a thermometer, a mercury-sealed mechanical stirrer and a double-surface reflux condenser. It is important that all the apparatus be thoroughly dry. Place 212 g. of trimethylene dibromide (Section 111,35) and 160 g. of ethyl malonate (Section 111,153) (dried over anhydrous calcium sulphate) in the flask. By means of a separatory funnel, supported in a retort ring and fitted into the top of the condenser with a grooved cork, add with stirring a solution of 46 g. of sodium in 800 ml. of super dry ethyl alcohol (Section 11,47,5) (I) at such a rate that the temperature of the reaction mixture is maintained at 60-65° (50-60 minutes). When the addition is complete, allow the mixture to stand until the temperature falls to 50-55°, and then heat on a water bath until a few drops of the liquid when added to water are no longer alkaline to phenolphthalein (about 2 hours). Add sufficient water to dissolve the precipitate of sodium bromide, and remove the alcohol by distillation from a water bath. Arrange the flask for steam distillation (Fig. this merely involves... 

Diethylbarbituric acid. In a dry 250 ml. distilling flask, fitted with a thermometer reaching to within 3-4 cm. of the bottom and a condenser, place 51 g. of clean sodium and add 110 g. (140 ml.) of super-dr ethyl alcohol (Section 11,47,5). When all the sodium has reacted, introduce 20 g. of ethyl diethylmalonate and 7 0 g. of dry imea (dried at 60 for 4 hours). Heat the flask in an oil bath and slowly distil off the ethyl alcohol. As soon as the temperature of the liquid reaches 110-115°, adjust the flame beneath the bath so that the contents of the flask are maintained at this temperature for at least 4 hours. Allow the flask to cool somewhat, add 100 ml. of water and warm until the solid (veronal-sodium) dissolves. Pour the solution into a beaker, and add a further 100 ml. of water but containing 7 0 ml. of concentrated siilplmric acid this will hberate the veronal from the sodium derivative. The veronal usually crystallises out if it does not, add a few more drops of dilute sulphuric acid until the solution is acid to Congo red. Heat the contents of the beaker, with stirring and the addition of more water if necessary, until all the veronal dissolves at the boiling point. Allow the hot solution to cool, filter off the crystals of veronal and diy in the air. The yield is 12 g., m.p. 190°. 

Ethyl phenylethylmalonate. In a dry 500 ml. round-bottomed flask, fitted with a reflux condenser and guard tube, prepare a solution of sodium ethoxide from 7 0 g. of clean sodium and 150 ml. of super dry ethyl alcohol in the usual manner add 1 5 ml. of pure ethyl acetate (dried over anhydrous calcium sulphate) to the solution at 60° and maintain this temperature for 30 minutes. Meanwhile equip a 1 litre threenecked flask with a dropping funnel, a mercury-sealed mechanical stirrer and a double surface reflux condenser the apparatus must be perfectly dry and guard tubes should be inserted in the funnel and condenser respectively. Place a mixture of 74 g. of ethyl phenylmalonate and 60 g. of ethyl iodide in the flask. Heat the apparatus in a bath at 80° and add the sodium ethoxide solution, with stirring, at such a rate that a drop of the reaction mixture when mixed with a drop of phenolphthalein indieator is never more than faintly pink. The addition occupies 2-2 -5 hoius continue the stirring for a fiuther 1 hour at 80°. Allow the flask to cool, equip it for distillation under reduced pressure (water pump) and distil off the alcohol. Add 100 ml. of water to the residue in the flask and extract the ester with three 100 ml. portions of benzene. Dry the combined extracts with anhydrous magnesium sulphate, distil off the benzene at atmospheric pressure and the residue under diminished pressure. C ollect the ethyl phenylethylmalonate at 159-160°/8 mm. The yield is 72 g. 

It should be mentioned that in the last few years super-cooled water has attracted the interest of many scientists because of its exceeding properties and life at temperatures below 0 °C 1819). Speedy recently published a model which allows for the interpretation of the thermodynamic anomalies of supercooled water 20). According to this model there are hydrogen bonded pentagonal rings of water molecules which have the quality of self-replication and association with cavities. 

The general theoretical treatment of ion-selective membranes assumes a homogeneous membrane phase and thermodynamic equilibrium at the phase boundaries. Obvious deviations from a Nemstian behavior are explained by an additional diffusion potential inside the membrane. However, allowing stationary state conditions in which the thermodynamic equilibrium is not established some hitherto difficult to explain facts (e.g., super-Nemstian slope, dependence of the selectivity of ion-transport upon the availability of co-ions, etc.) can be understood more easily. 

In order to make practical use of the physical properties of nanoparticles, whether individual or collective, one has to find a way to address them. If we leave out the near field techniques, this in turn requires that the particles be monodisperse and organized in two or three dimensions. It is therefore necessary to imagine techniques allowing the self-organization and even, ideally, the crystallization of nanoparticles into super-lattices. 

Ttie sodium ethoxide solution is convenioiitly prepared as follows. Place 46 g. of dean sodium (Section III,7, Note 7) in a 2 litre round-bottomed flask provided with a 25 cm. double surface condenser. The apparatus must be perfectly dry. Cool the flask in a bath of crushed ice. Add 800 ml. of super-dry ethyl alrohol in one operation. A vigorous reaction will ensue, but it will remain under eontool. When the initial reaction is over, remove the ice bath and allow the le ual sodium to react. If smaU quantities of sodium remain, warm the flask water bath until solution is complete. 

---