An investigation of the electrochemical performance of a silver/zeolite 4AI2 solid-state cell

Dehydrated zeolite 4A crystals (Na₁₂Al₁₂Si₁₂O₄₈), impregnated with I₂, have been used as cathode material in a silver/ iodine solid-state cell. Two quaternary amine iodide/AgI solid electrolytes, viz. Ag₄₄I₅₃(C₁₁H₃₀N₃)₃ and Ag₂₁I₂₅ (C₉H₂₄N₂)₂ having room-temperature ionic conductivities of $\text{≈ 3 × 10}{}^{\mathrm{?2}}\text{Ω}{}^{\mathrm{?1}}\text{cm}{}^{\mathrm{?1}}$ were used in the investigation. The discharge caracteristics of two cells, having open-circuit voltages of ≈ x640 mV, are reported. The cells were discharged under a 10 kΩ load at room temperature to a cut-off voltage of 100 mV. Cathode efficiencies of ≈ 60% were recorded.     

Zero sound in dense neutron matter

Propagation of zero sound in dense neutron matter is investigated within the framework of the Landau theory of normal Fermi liquids. The effect of the spin polarization of the medium is studied. A calculation performed using the quasi-particle interaction derived from the Reid soft-core nucleon-nucleon potential shows that zero sound can propagate in neutron matter for densities greater than $\text{?}{}^1\text{≈ 0.4–0.5}\text{neutrons/fm}{}^3$, and is strongly damped at densities below ?¹.     

Quark masses

In quark gluon theory with very small bare masses, -$\text{ψ}$$\text{M}$ψ, spontaneous breakdown of chiral symmetry generates sizable masses M_u, M_d, M_s, … We find ($\text{M}{}_{\mathrm{<mtext>u</mtext>}}\text{+ M}{}_{\mathrm{<mtext>d</mtext>}}\text{) /2 ≈ m}\text{p}\text{/ √6 ≈ 312}\text{MeV}\text{,}\text{and}\text{M}{}_{\mathrm{<mtext>s</mtext>}}\text{≈ 432}\text{MeV}$. Scalar densities have well determined non-zero vaccum expectations $\text{〈0|u}{}^{\mathrm{a}}\text{|0〉 ≡ 〈0|ψ(x) (λ}{}^{\mathrm{a}}\text{/2)ψ(x)/0〉 ≈ ?}{}_{\mathrm{\pi }}{}^2\text{M}{}^{\mathrm{a}}\text{,}\text{i.e}\text{〈0? u}{}^{\mathrm{o}}\text{/vb0〉 ≈ 8 × 10}{}^{\mathrm{?3}}\text{(}\text{GeV}\text{)}{}^3$ at an SU(3) breaking of the vacuum c′ ≡ 〈0|u⁸|〉/〈0|u^o|0〉 ≈ ? 16%     

Anomalous ionic conduction in AgBrAgI mixed crystals and multiphase systems

Ionic conductivity, σ, of the AgBrAgI system has been studied as a function of composition and temperature. The maximum conductivity of $\text{3 × 10}{}^{-4}\text{Ω}{}^{\mathrm{?1}}\text{cm}{}^{\mathrm{?1}}$ at 25°C is obtained for a AgI-20 mole% AgBr two-phase mixture which is $\text{\$}\text{?}$3 orders of magnitude larger than that predicted by the classical theories of Lord Rayleigh and Maxwell. On the other hand, the substitution of so-called homovalent ions, e.g. Br^? in AgI and I^? in AgBr one phase solid solutions leads to anomalously large increase in the ionic conductivity that cannot be explained in terms of the charge compensation (doping) mechanism, and is attributed to purely elastic displacements (lattice distortion) due to the very “wrong” size of the substituted ions. A quadratic dependence of conductivity on the concentration of substituents is substantiated. An important consequence of the latter anomaly is that AgBr + 30 mole% AgI exhibits σ $\text{\$}\text{?}$7 Ω^?1 cm^?1 at 380°C which is $\text{\$}\text{?}$170% higher than that of α-AgI, the best known superionic conductor, at its melting point (557°C).     

A thermodynamic study of nonstoichiometric cerium dioxide

Thermogravimetric measurements were performed on nonstoichiometric CeO_2?x in the temperature range 750–1500°C and from oxygen pressures of 10^?2 to 10^?26 atm. From this data the deviation from stoichiometry x = x(T, P_o2) was determined. The thermodynamic quantities Δ$\text{H}$_o2 and Δ$\text{S}$_o2 were calculated in the region 0.001? x ? 0.3 and found to be independent of temperature.In the composition region 0.001< x < 0.006, the variation of Δ$\text{S}$_o2 with x is consistent with a defect model involving randomly distributed doubly ionized oxygen vacancies. The experimental dependence of x and σ (electrical conductivity) is shown to be consistent with this model as Δ$\text{H}$_o2 (≈ -10 eV) exhibits a slight dependence on x. It is postulated that the variation in Δ$\text{H}$_o2 may result from lattice parameter increases with x, while the defects remain essentially randomly distributed.In the composition region 0.006 < x < 0.1, x ∝ with 1 < n < 5, and in the region 0.1 < x < 0.3, x ∝ with n increasing rapidly with x to n? 30. This behavior is believed to result from increasing defect interaction with increasing departures from stoichiometry. It is interesting to note that the ordered phase observed by Bevan and Kordis between CeO_1·72 and CeO_1·70 was not observed in this study at temperatures between 1300° and 1500°C.     

Investigation of rare non-strange decay modes of the f meson in Π+p interactions at 5GeVc

Rare decay modes of the f meson are studied in the final states Δ⁺⁺π⁺π^?π⁺π^?, Δ⁺⁺π⁺π^?MM and Δ⁺⁺π⁺π^?π⁺π^?MM. The ratio $\text{Γ (f → π}{}^{\mathrm{+}}\text{π}{}^{\mathrm{?}}\text{π}{}^0\text{π}{}^0\text{)}\text{Γ(f → π}{}^{\mathrm{+}}\text{π}{}^{\mathrm{?}}\text{)}$ is 0.23 ± 0.09 and Γ(f → 4 π) saturates the f inelasticity. A 2 s.d. upper limit of 0.09 is found for the branching ratio $\text{(f → ηη)}\text{(f → 2π)}$.     

Gamow-Teller strength function for 26Mg→26Al

A shell-model study of the total Gamow-Teller (GT) distribution for the ${}^{26}\text{Mg}\text{→}{}^{26}\text{Al}$ transition has yielded good agreement with the 0° experimental (p, n) results when normalized to the β-decay rates of the two lowest-lyiong 1⁺ states in ²⁶Al. This normalization corresponds to a GT quenching of ≈40%, in good agreement with the Δ-isobar model prediction of Bohr and Mottelson     

Paзлoжeниe пo 1Z для чapтpи-фoкoвcкoй и кoppeляциoннoй энepгии, peлятивиcтcкич пoпpaвoк, дипoльнoгo мaтpичнoгo элeмeнтa

Energies and dipole matrix elements have been calculated for He, Li, Be, B, C, N, O, F, and Ne-like ions (configurations 1s²2sⁿ¹2pⁿ²?1s²2s^n1?12pⁿ²⁺¹). The Hartree-Fock energy, the correlation energy, and relativistic corrections were taken into account. Relativistic corrections were obtained by computing the entire quantity H_B. Numerical results are presented for energies of the terms in the form

$\text{E=E}{}_0\text{Z}{}^2\text{+ ΔE}{}_1\text{Z + ΔE}{}_2\text{+}\text{1}\text{Z}\text{ΔE}{}_3\text{+}\text{α}{}^2\text{4}\text{(E}{}_0{}^{\mathrm{p}}\text{Z}{}^4\text{+ ΔE}{}_1{}^{\mathrm{p}}\text{Z}{}^3\text{)}$

, and for the fine structure of the terms in the form

$\text{〈1s}{}^2\text{2s}{}^{\mathrm{n1}}\text{2p}{}^{\mathrm{n2}}\text{LSJ|H}{}_{\mathrm{Б}}\text{|1s}{}^2\text{2s}{}^{\mathrm{n1\prime }}\text{2p}{}^{\mathrm{n2\prime }}\text{L′S′J〉=(?1)}{}^{\mathrm{L+S\prime +J}}\text{LSJ}\text{S′L′1}\text{×}\text{α}{}^2\text{4}\text{(Z?A)}{}^3\text{[E}{}^{\mathrm{(0)}}\text{(Z ? B)+}\text{E}{}_{\mathrm{c0}}\text{]+(?1)}{}^{\mathrm{L\; +\; S\prime \; +\; J}}\text{LSJ}\text{S′L′2}\text{α}{}^2\text{4}\text{(Z?A)}{}^3\text{E}{}_{\mathrm{cc}}$

. Dipole matrix elements are required for calculation of oscillator strengths or transition probabilities. For the dipole matrix elements, two terms of the expansion in $\text{1}\text{Z}$ have been obtained. Numerical results are presented in the form P(a, a′) = (a/Z)[1 + (τ/Z)].     

The reactions K−p → K1− + nucleon at 3.13 and 3.3 GeV/c

Results are presented of a 12 event/μb bubble-chamber experiment; the reactions discussed in detail are $\text{K}{}^{\mathrm{?}}\text{p}\text{→}\text{K}{}^1\text{(890)}{}^{\mathrm{?}}\text{p, K}{}^1\text{(1420)}{}^{\mathrm{?}}\text{p and K}{}^1\text{(890)}{}^{\mathrm{?}}\text{Δ}{}^{\mathrm{+}}$.The K¹ (890)^?p channel is dominated by the forward peak. The suggestion of flattering at cos θ = 1 is more pronounced in $\text{(?}{}_{11}\text{+ ?}{}_{\mathrm{1?1}}\text{)}\text{d}\text{σ}\text{d}\text{t}$; which is mainly natural-parity exchange. Pseudoscalar exchange contributes to $\text{?}{}_{00}{}^{\mathrm{J}}\text{d}\text{σ}\text{d}\text{t}$; this is more sharply peaked in t. The value of $\text{(?}{}_{11}\text{? ?}{}_{\mathrm{1?1}}\text{)}\text{d}\text{σ}\text{d}\text{t}$ is somewhat larger than the upper limit from the dominant natural-parity exchange. There is significant structure in $\text{?}{}_{00}{}^{\mathrm{H}}\text{d}\text{σ}\text{d}\text{t}\text{at}\text{t ≈ ?0.6 (}\text{GeV}\text{/c)}{}^2$.The K¹ (1420)^?p channel is much more pronounced at 3.3 GeV/c than at 3.13 GeV/c, but is not markedly peripheral. The width of the K¹ (1420) in the 3.3 GeV/c data is 42 ± 12 MeV/c².The cross section for $\text{K}{}^{\mathrm{1?}}\text{Δ}{}^{\mathrm{+}}$ agrees with that expected from $\text{K}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^1\text{Δ}$, assuming a single t-channel exchange. Our measured density matrix elements are consistent with a strong pseudoscalar exchange.     

Superfluidity of neutron matter: (II). Triplet pairing

The possibility of neutron triplet pairing and superfluidity in neutron star matter is investigated, and the energy gap and corresponding critical temperature is calculated or estimated as a function of Fermi momentum or density. The calculations are performed for a “one-pion-exchange gaussian” potential, and compared with the results for neutron and proton singlet pairing and superfluidity calculated earlier.The results indicate that neutron superfluidity, corresponding specifically to ³P₂ state pairing, may exist in a high-density shell in the nuclear-matter region of a neutron star, i.e. for 1.6 × 10¹⁴g/cm³ < ρ < 1.4 × 10¹⁵g/cm³, and the maximum self-consistent energy gap is Δ⁰₁k_F ≈ 0.6 MeV and Δ⁰₃(k_F) ≈ 0.1 MeV for an effective mass $\text{m}{}^1\text{≈ 0.75}\text{and}\text{k}{}_{\mathrm{<mtext>F</mtext>}}\text{≈ 2.1}\text{fm}{}^{\mathrm{?1}}$, i.e. for a mas ? ≈ 5.2 × 10¹⁴g/cm³. For $\text{m}{}^1\text{= 1.0}$ we get correspondingly Δ⁰₁(k_F) ≈ 3.3 MeV and Δ⁰₃(k_F) ≈ 0.6 MeV for k_F ≈ 2.2 fm^?1.     

Giant spin-isospin vibrations and the continuum spectra from the (p,n) reaction at forward angles

The giant Gamow-Teller (GT) resonance and the spin-isospin multipole vibrations are calculated in terms of the continuum RPA. The effective particle-hole interaction consists of the Migdal parameter $\text{g′ = 0.7 (}\text{in units of}\text{?;}{}^2\text{μ}{}_{\mathrm{\pi }}{}^2\text{≈390}\text{MeV}\text{·}\text{fm}{}^3\text{)}$ and the one-pion exchange potential. The RPA response functions are obtained within the full 1p-1h space. In addition to the natural escaping width of the single particle, a constant spreading width for 1p-lh states is incorporated into the correlation function, which makes numerical calculations fast and feasible. The giant GT resonances in ⁹⁰Zr and ²⁰⁸Pb collect, respectively, about 80% and 93% strengths of the sum-rule limit within the nucleon degrees of freedom. It is found that the strengths are further quenched by about 30% due to the coupling with the isobar Δ(1230)-hole configuration. The total quenching thus amounts to 0≈45% and ≈40% respectively in two cases, which is in fair agreement with experiment. The continuum cross section of the ⁹⁰Zr(p, n) reaction at forward angles are calculated for spins up to J = 4 with both parities in the distorted-wave Born approximation. While the giant GT resonance is located at a low excitation energy $\text{h}\text{?}\text{ω ≈ 17}\text{MeV}$, the broad peaks of the dipole and quadrupole modes are found to dominate at $\text{h}\text{?}\text{ω ≈ 25}\text{and}\text{35}\text{MeV}$, respectively. The calculation fairly reproduces the experimental inclusive cross sections up to $\text{h}\text{?}\text{ω ≈ 50}\text{MeV}$.     

Theory of the input power-dependence of the electron heating in n-inversion layers

The average energy loss P of hot electrons due to the interaction with acoustic bulk phonons is calculated and used to determine the electron heating temperature Δ as a function of the input power eμE². It is found that P creases proportional to Δ² and is independent of the carrier concentration. Consequently the ratio Δ/√ eμE² turns out to be a constant $\text{(0.75 × 10}{}^{\mathrm{?2}}\text{K/(eV/s)}{}^{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ for $\text{n-Si and 2.04 × 10}{}^{\mathrm{?2}}\text{K/(eV/s)}{}^{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ for n-GaAs) in agreement with the experimental data deduced from FIR-emission experiments at T = 4.2 K.     

A study of resonance production in the reaction K+p → K0pπ+ from 3 to 16 GeV/c

The reactions $\text{K}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{1+}}\text{(890)}\text{p}$, $\text{K}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{1+}}\text{(1420)}\text{p}$ and K⁺p → K⁰Δ⁺⁺ have been systematically studied for eleven incident momenta between 3.0 and 16.0 GeV/c. Cross sections, differential cross sections and density matrix elements are presented. For K¹(890) production the contributions from natural and unnatural parity exchanges have also been separated into I = 0 and I = 1 components. Effective trajectories have been extracted in the case of natural parity exchange, and also for Δ⁺⁺ production.     

Observed and calculated interactions between valence states of the NO molecule

No perturbation between two valence states of NO has ever been identified, although many valence-Rydberg and several Rydberg-Rydberg perturbations have been extensively studied. The first valence-valence crossing to be experimentally documented for NO is reported here and occurs between the ¹⁵N¹⁸O B²Π (v = 18) and B′²Δ (v = 1) levels. No level shifts larger than the detection limit of 0.1 cm^?1 are observed at the crossings near $\text{J = 6.5 [B}{}^2\text{Π}\text{(F}{}_1\text{) ～ B′}{}^2\text{Δ}\text{(F}{}_2\text{)]}$ and $\text{J = 12.5 [B}{}^2\text{Π}\text{(F}{}_1\text{) ～ B′}{}^2\text{Δ}\text{(F}{}_1\text{)]}$; two crossings involving higher rotational levels could not be examined. Semi-empirical calculations of spin-orbit and Coriolis perturbation matrix elements indicate that although the electronic part of the $\text{B}{}^2\text{Π}\text{～ B′}{}^2\text{Δ}$ interaction is large, a small vibrational factor renders the ¹⁵N¹⁸O B (v = 18) ? B′ (v = 1) perturbation unobservable. Semi-empirical estimates are given for all perturbation matrix elements of the operators $\text{Σ}{}_{\mathrm{i}}\text{a}\text{?}{}_{\mathrm{i}}\text{l}{}_{\mathrm{i}}\text{·s}{}_{\mathrm{i}}$ and $\text{B(L}{}_{\mathrm{\pm }}\text{S}{}_{\mathrm{?}}\text{? J}{}_{\mathrm{\pm }}\text{L}{}_{\mathrm{?}}\text{)}$ which connect states belonging to the configurations $\text{(σ2p)}{}^2\text{(π2p)}{}^4\text{(π}{}^1\text{2p)}$, $\text{(σ2p)(π2p)}{}^4\text{(π}{}^1\text{2p)}{}^2$, and $\text{(σ2p)}{}^2\text{(π2p)}{}^3\text{(π}{}^1\text{2p)}{}^2$.     

The spectrum of HeAr+

Two band groups near 1450 Å, first observed by Tanaka, Yoshino, and Freeman (J. Chem. Phys.62, 4484–4496 (1975)) in discharges through mixtures of helium and argon and assigned by them to the HeAr⁺ ion, were studied under high resolution. Like the similar spectrum of HeNe⁺ previously investigated, the spectrum of HeAr⁺ is a charge transfer spectrum. The upper state B²Σ⁺ of both band groups is derived from $\text{He}{}^{\mathrm{+}}\text{(}{}^2\text{S) +}\text{Ar}\text{(}{}^1\text{S)}$ while the two lower states $\text{A}{}_2{}^2\text{Π}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ and X²Σ⁺ are derived from $\text{He}\text{(}{}^1\text{S) +}\text{Ar}{}^{\mathrm{+}}\text{(}{}^2\text{P)}$. All three states are very weakly bound, the two lower states even more weakly than the upper state. Unlike HeNe⁺ most of the HeAr⁺ bands are violet shaded. In the longward band group each band shows only three branches while in the shortward group there are four. The former observation shows that the $\text{A}{}_2{}^2\text{Π}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ state behaves like a ²Σ^? state with γ_v ≈ 0. The B, D, γ, p, and ΔG values of all states were evaluated. While the B_v values of upper and lower states are nearly equal, the D_v values are quite different and this difference accounts for the violet shading of most of the bands even when B′_v is slightly smaller than B″_v; it also accounts for some of the extraheads and linelike features in the rotational structure. As in HeNe⁺ the ${}^2\text{Π}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$ component of ²Π was not observed.     

Edge emission of CdS crystals stimulated by infrared

Excitation in the band edge region of CdS (wave numbers $\text{v}\text{≈ 20,000}\text{cm}{}^{\mathrm{?1}}$) sensitizes the crystals in the far infrared range ($\text{v}\text{≈ 200}\text{cm}{}^{\mathrm{?1}}$). The resulting characteristic sensitized i.r. absorptions (SIRA) are used at T ≈ 5 K as a measuring probe for the degree of population of donors. These donors can be emptied by irradiation with red or near infrared light ($\text{v}\text{? 2000}\text{cm}{}^{\mathrm{?1}}$). At this stimulation process, the low energy series of the green edge luminescence is emitted.     

Investigation of the level schemes of 73,75,77As via the (3He,d) reaction

The reactions ^{72, 74, 76}Ge(³He, d) were investigated at E_lab = 23 MeV with a multigap and a Q3D magnetic spectrograph. Some 30 new levels up to $\text{E}{}^1\text{≈ 4}\text{MeV}$ have been found. The level schemes of the odd As isotopes ^{73, 75, 77}As up to $\text{E}{}^1\text{≈ 4}\text{MeV}$ seem to be rather independent of the neutron number. The good agreement of the low-lying level structure with the Coriolis-coupling model including a pairing force was verified and the vacancies of low-lying shell model states were extracted and compared with the simple pairing theory.     

In-beam γ-ray studies of complex band structures and of isomeric states in 152, 153Dy nuclei

The high-spin level structures of ¹⁵²Dy and ¹⁵³Dy were studied experimentally with ^{154, 155}Gd(α xnγ) in-beam reactions, and for ¹⁵²Dy also with ${}^{\mathrm{144,\; 146}}\text{Nd}\text{(}{}^{12}\text{C, x}\text{n}\text{γ)}$ reactions. The experiments included measurements of singles γ-ray and conversion-electron spectra, γ-ray angular distributions and E_γ-t and E_γ-E_γ-t coincidences. A multiplicity filter set-up was used to study the feeding and decay of isomeric states in ¹⁵²Dy. In ¹⁵²Dy about twenty so far unknown levels were found, including two high-spin isomeric states with $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{≈ 60}\text{and}\text{≈ 13}\text{ns}$ at excitation energies E_x ≈ 5.04 and 6.08 MeV, respectively. These states are compared with recent calculations on yrast traps. The level scheme of ¹⁵³Dy contains 28 levels up to E_x = 4.1 MeV and $\text{J}{}^{\mathrm{\pi }}\text{= (}\text{37}\text{2}{}^{\mathrm{+}}\text{)}$. Band structures in both nuclei are discussed in comparison with other N = 86 and N = 87 isotones.     

Franck-Condon factors and r-centroids for the (D1Π−X1Σ+) transition of SiS molecule using R-K-R-V potential

Turning points of the vibrating SiS molecule in the D¹Π and X¹Σ⁺ electronic states are evaluated using R-K-R-V method. Franck-Condon (FC) factors and r-centroids are computed for the $\text{(}\text{D}{}^1\text{Π?}\text{X}{}^1\text{Σ}{}^{\mathrm{+}}\text{)}$ transition of the molecule using wavefunctions appropriate to R-K-R-V potential energy curves. The results of the FC-factors vary in accordance with the estimated intensities and also satisfy the vibrational sum rule. The sequence difference Δr remains approximately constant in the computed r-centroids.     

Simultaneous production of K1o (892) and Δ++(1236) in the reaction K+p→K+π+π−p from 4.3 to 5.0 GeV/c

The reaction $\text{K}{}^{\mathrm{+}}\text{d}\text{→}\text{K}{}^{\mathrm{1o}}\text{(892) Δ}{}^{\mathrm{++}}\text{(1236)}\text{n}{}_{\mathrm{s}}$ from a K⁺d experiment with the CERN 2 m bubble chamber at 4.6 GeV/c is compared with the reaction $\text{K}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{1o}}\text{(892)Δ}{}^{\mathrm{++}}\text{(1236)}$ from a K⁺p experiment at the same energy. In addition, predictions of an absorption model, a Regge pole model and a quark model for the production and decay characteristics of the reaction $\text{K}{}^{\mathrm{+}}\text{p}\text{→}\text{K}{}^{\mathrm{1o}}\text{(892)Δ}{}^{\mathrm{++}}\text{(1236)}$ are tested with the combined statistics of the K⁺d experiment and three K⁺p experiments between 4.3 and 5.0 GeV/c.