The energy of disintegration of radio-phosphorous [P
            30
            ]

The exact masses of the nuclei are quantity of great interest depending directly on the forces of cohesion between the nuclear particles. Already much valuable information has been obtained about the lighter element both by mass-spectrographic methods and by the study of atomic dis-integrations. The discovery of the new radioactive elements has extended greatly the number of nuclei open to investigation, but since nearly all of these disintegrate by emitting either positrons or electrons forming a continuous spectrum we meet here the same difficulty in determining the total energy change in the disintegration as with the natural β-ray bodies. In this latter case Henderson* has proved the correcting of the suggestion of Ellis and Mott that the difference of energy of two nuclei, apart from γ-emission, is given by the upper limit of the β-ray spectrum. However, as was emphasized by Cockroft at the British Association Meeting at Norwich, in September, 1935, this is a point which needs verification in the region of low atomic number and particularly for positron disintegration. We have attempted to obtain some information on this point by investigating the disintegration of radio-phosphorus [P30] formed from aluminium by α-particle bombardment, The disintegration of radio phosphorus has already been investigated several times, but there is such a notable disagreement between the values given by different observers for the energy of the upper limit that we felt fresh experiments were needed, further, it is necessary to determine whether the upper limit corresponds to the formation of the ground state or of an excited state of the product nucleus.

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Solvent effect on the absorption and emission spectra of carbon dots: evaluation of ground and excited state dipole moment

BMC Chemistry ◽

10.1186/s13065-021-00779-6 ◽

2021 ◽

Vol 15 (1) ◽

Author(s):

Parisa Mohammad-Jafarieh ◽

Abolfazl Akbarzadeh ◽

Rahman Salamat-Ahangari ◽

Mohammad Pourhassan-Moghaddam ◽

Kazem Jamshidi-Ghaleh

Keyword(s):

Dipole Moment ◽

Excited State ◽

Ground State ◽

Carbon Dots ◽

Dipole Moments ◽

Emission Spectra ◽

Aprotic Solvents ◽

One Step ◽

The Difference ◽

Excited State Dipole Moment

Abstract Background Carbon dots (C-dots) are photoluminescent nanoparticles with less than 10 nm in size. Today, many studies are performed to exploit the photoluminescence (PL) property of carbon dots, and our focus in this study is to estimate the dipole moment of carbon dots. For reaching our aims, C-dots were synthesized and dissolved in the different solvents. Results Carbon dots with intense photoluminescence properties have been synthesized by a one-step hydrothermal method from a carbon bio-source. In this research, we report on the effect of aprotic solvents on absorption and fluorescence spectra and dipole moments of C-dots dispersed in a range of many aprotic solvents with various polarity and dielectric constant at room temperature. The change in the value of dipole moment was estimated by using the Stokes shifts. The difference between the dipole moment of the excited state and the ground state was shown using an extended form of Lippert equations by Kawski and co-workers. Conclusions The values found for μg = 1.077 D, and μe = 3.157 D, as well as the change in the dipole moments. The results showed that the dipole moment of the excited state is more than the ground state, indicating a high density and redistribution of electrons in the excited state. Finally, the quantum yield of C-dots in the eclectic aprotic solvents was communicated and discussed.

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Absorption and coincidence experiments on the radiations from the radioactive sodium, Na24

Mathematical Proceedings of the Cambridge Philosophical Society ◽

10.1017/s0305004100020399 ◽

1938 ◽

Vol 34 (3) ◽

pp. 442-449 ◽

Cited By ~ 16

Author(s):

N. Feather ◽

J. V. Dunworth

Keyword(s):

Energy Spectrum ◽

Continuous Spectrum ◽

Ground State ◽

Cascade Process ◽

Γ Radiation ◽

Upper Limit ◽

Single Transition ◽

Radioactive Sodium

The radiations from Na24 have been examined by the absorption and coincidence methods and evidence has been obtained for the conclusion that the energy spectrum of the β-particles is a simple continuous spectrum with an upper limit at 1·40 × 106 e.V., and that the emission of γ-radiation after the particle disintegration takes place almost always as a cascade process in which at least two quanta are involved, and very rarely by a single transition to the ground state.

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Constraints on the spatial variation of Planck constant

The European Physical Journal Plus ◽

10.1140/epjp/s13360-021-01768-3 ◽

2021 ◽

Vol 136 (8) ◽

Author(s):

Emilio Fiordilino

Keyword(s):

Spatial Variation ◽

Physical Parameter ◽

Ground State ◽

Laser Pulses ◽

Planck Constant ◽

Upper Limit ◽

The Earth ◽

Atomic Ground State ◽

The Difference ◽

State Of Art

AbstractInspired by recently published researches, we present two protocols for setting an upper limit to the claimed variation of $$\hbar $$ ħ upon the position. The protocols, both within today state of art, involve the use of two delayed laser pulses driving an atom. The distinct positions of the laboratory, due to the Earth motion, affects $$\hbar $$ ħ and hence the atomic dynamics. The first protocol measures the difference in population of the atomic ground state while the second one the red-shift of the harmonics emitted by the atom in the two moments of the experiment. The protocols improve the reported upper limit of $$\varDelta \hbar /\hbar $$ Δ ħ / ħ . The theory shows that $$\hbar (\varvec{r})$$ ħ ( r ) induces a chaotic evolution to the atom. This form of Chaos is generated by a variation of a physical parameter and is one example of Parametric Chaos.

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Neutrons from Deuteron Bombardment of Boron

Australian Journal of Physics ◽

10.1071/ph570268 ◽

1957 ◽

Vol 10 (2) ◽

pp. 268 ◽

Cited By ~ 4

Author(s):

JR Bird ◽

RH Spear

Keyword(s):

Excited State ◽

Compound Nucleus ◽

Ground State ◽

Angular Distributions ◽

Particle Model ◽

Upper Limit ◽

First Excited State ◽

Compound Nucleus Formation ◽

Deuteron Bombardment ◽

Peak Widths

A natural boron target has been bombarded by 920 keV deuterons, and the emitted neutrons detected using nuclear emulsions. A new procedure for analysing measurements is described ; this procedure allows approximate corrections for errors in geometry in the plane of the emulsions. The dependence of resolution on various experimental factors has been studied, and the resolution achieved is indiCated by peak widths of 245 � 25keV and 360 � 50 keV at neutron energies of 9�7 MeV and 13�9 MeV respectively. The angular distributions of the neutrons from the 10B(d,n)l1C reaction corresponding to the ground state of 11C, and the neutrons from the 11B(d,n)12C reaction corresponding to the 7�66 Me V state in 12C, have been determined; both distributions may be attributed to compound nucleus formation. A search has been made for a neutron group corresponding to an excited state at about 5�5 MeV in 12C suggested by Glassgold and Galonsky (1956) on the basis of the a-particle model. An upper limit for the intensity of any such group is set at 1 per cent. of the intensity of the group corresponding to the first excited state in 12C.

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Energy values for some proton and deuteron reactions with 6 Li, 7 Li, 9 Be, 11 B and 15 N

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1953.0019 ◽

1953 ◽

Vol 216 (1125) ◽

pp. 242-246 ◽

Cited By ~ 14

Keyword(s):

Excited State ◽

Nuclear Reaction ◽

Ground State ◽

Excited Level ◽

Average Value ◽

First Excited State ◽

Reaction Energies ◽

The Difference

The following values of nuclear reaction energies have been obtained: 6 Li (p,α) 3 He, Q = 4.023 MeV; 8 Li (d ,p) 7 Li, Q = 5.028 MeV; 6 Li (d, p ) 7* Li, Q= 4.553 MeV; 6 Li( d,α ) α, Q = 22.396 MeV; 7 Li (p , α ) α , Q = 17.352 MeV; 9 Be (p, α ) 6 Li, Q = 2.126 MeV; 9 Be (p, d ) 8 Be, Q = 0.560 MeV; 9 B e (d, α ) 7 Li, Q = 7.153 MeV; 9 Be (d, α ) 7* Li, Q = 6.675 MeV; n B (p , α ) 8 Be, Q = 8.589 MeV; 15 N (p, α ) 12 C, Q = 4.962 MeV. The average value of th e first excited level in 7 Li has been found to be 0.477 ± 0.003 MeV from the difference between the ground state and first excited state groups of the 6 Li (d, p) 7 Li and 9 Be (d, α) 7 Li experiments. A comparison is made between the above results and recent figures quoted by other workers in this field, and it is found that no systematic discrepancies are conspicuous, except that our energies are on the average higher than those found at M.I.T. and C.I.T., probably due to the differences between the momentum and energy standards used by these groups of workers and those measured by us.

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Determination of a High Potential Barrier Hindering Internal Rotation from the Microwave Ground State Spectrum The Methylbarrier of Antiperiplanar and Synclinal Normal Propyl Fluoride

Zeitschrift für Naturforschung A ◽

10.1515/zna-1986-0708 ◽

1986 ◽

Vol 41 (7) ◽

pp. 944-954

Author(s):

W. Kasten ◽

H. Dreizler

Keyword(s):

Excited State ◽

Ground State ◽

Barrier Heights ◽

Distortion Analysis ◽

First Excited State ◽

High Potential Barrier ◽

The Difference ◽

Methyl Torsion ◽

Approximate Treatment

The microwave ground state spectra of antiperiplanar and synclinal normal propyl fluoride have been measured by microwave Fourier transform spectroscopy and analysed for methyl torsion fine structure. Additionally, the spectrum of the synclinal form in the first excited state of the methyl group has been investigated due to methyl torsion. The difference of the values determined for the barrier heights in the ground and first excited state of the synclinal form is discussed by an approximate treatment of the coupling of CH3 and C - C torsional motions. As high J transitions were measured a centrifugal distortion analysis was necessary.

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RADIOACTIVE DECAY OF W188

Canadian Journal of Physics ◽

10.1139/p62-072 ◽

1962 ◽

Vol 40 (6) ◽

pp. 677-686 ◽

Cited By ~ 7

Author(s):

J. C. Roy

Keyword(s):

Excited State ◽

Gamma Rays ◽

Ground State ◽

Half Life ◽

Decay Scheme ◽

Radioactive Decay ◽

Beta Transition ◽

Upper Limit ◽

Gamma Radiations

The half-life of W188 has been measured to be 69.4 ± 0.5 days. The gamma radiations emitted in the decay of W188 have been studied with an NaI scintillation spectrometer, and the beta radiations by absorption in aluminum. Three gamma rays with energies of 0.290 ± 0.005, 0.227 ± 0.005, and 0.063 ± 0.005 Mev were observed. The intensities of these gamma rays were measured relative to those gamma rays from the daughter activity Re188. The W188 gamma intensities thus deduced are respectively 0.002, 0.001, and about 0.001 per disintegration. The 0.227 and 0.063 gamma rays are in coincidence. It logically follows from the gamma results that 99.3% of the beta radiations go to the ground state of Re188 with an energy of 0.36 ± 0.04 Mev (determined by Feather analysis), while about 0.4% go to an excited state at 0.290 Mev; an upper limit of 0.3% has been set for a beta transition to the 0.063 state. A decay scheme for W188 is proposed.

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LOCV CALCULATIONS FOR POLARIZED LIQUID 3He WITH THE SPIN-DEPENDENT CORRELATION

International Journal of Modern Physics B ◽

10.1142/s0217979209052340 ◽

2009 ◽

Vol 23 (10) ◽

pp. 2373-2382 ◽

Cited By ~ 9

Author(s):

G. H. BORDBAR ◽

M. J. KARIMI

Keyword(s):

Correlation Function ◽

Total Energy ◽

Ground State ◽

Zero Temperature ◽

Lennard Jones ◽

Pair Potentials ◽

Independent Case ◽

Spin Triplet ◽

The Difference ◽

Dependent Correlation

We have used the lowest order constrained variational (LOCV) method to calculate some ground-state properties of polarized liquid 3 He at zero temperature with the spin-dependent correlation function employing the Lennard–Jones and Aziz pair potentials. We have seen that the total energy of polarized liquid 3 He increases with increasing polarization. For all polarizations, it is shown that the total energy in the spin-dependent case is lower than the spin-independent case. We have seen that the difference between the energies of spin-dependent and spin-independent cases decreases by increasing the polarization. We have shown that the main contribution of the potential energy comes from the spin-triplet state.

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Renilla Bioluminescence: A Morphologic Approach to the Location of Photocytes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051050 ◽

1974 ◽

Vol 32 ◽

pp. 208-209

Author(s):

Ben O. Spurlock ◽

Milton J. Cormier

Keyword(s):

Excited State ◽

Ground State ◽

Molecular Basis ◽

Light Emission ◽

Chemical Basis ◽

Electronic Excited State ◽

Colonial Form ◽

The Common ◽

Eighteenth And Nineteenth Centuries ◽

Catalyzed Oxidation

The phenomenon of bioluminescence has fascinated layman and scientist alike for many centuries. During the eighteenth and nineteenth centuries a number of observations were reported on the physiology of bioluminescence in Renilla, the common sea pansy. More recently biochemists have directed their attention to the molecular basis of luminosity in this colonial form. These studies have centered primarily on defining the chemical basis for bioluminescence and its control. It is now established that bioluminescence in Renilla arises due to the luciferase-catalyzed oxidation of luciferin. This results in the creation of a product (oxyluciferin) in an electronic excited state. The transition of oxyluciferin from its excited state to the ground state leads to light emission.

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