Geometric-arithmetic Index and Zagreb Indices of Certain Special Molecular Graphs

In this paper, we determine the Geometric-arithmetic indexand Zagreb indicesof fan molecular graph, wheel molecular graph, gear fan molecular graph, gear wheel molecular graph, and their r-corona molecular graphs

Three IndicesCalculationof Certain Crown Molecular Graphs

As molecular graph invariant topological indices, harmonic index, zeroth-order general Randic index and Co-PI index have been studied in recent years for prediction of chemicalphenomena. In this paper, we determine the harmonic index, zeroth-order general Randic index andCo-PI indexof certain r-crown molecular graphs

Deformation and orientation effects in the driving potential of the dinuclear model

A double-folding method is used to calculate the nuclear and Coulomb interaction between two deformed nuclei with arbitrary orientations. A simplified Skryme-type interaction is adopted. The contributions of nuclear interaction and Coulomb interaction due to the deformation and orientation of the nuclei are evaluated for the driving potential used in the description of heavy-ion fusion reaction. So far there is no satisfactory theory to describe the evolution of the dynamical nuclear deformation and orientations during the heavy-ion fusion process. Our results estimated the magnitude of above effects.Comment: 15 pages, 6 figures, Accepted by Eur. Phys. Jour.

Locally compact groups and locally minimal group topologies

Minimal groups are Hausdorff topological groups G satisfying the open mapping theorem with respect to continuous isomorphisms, i.e., every continuous iso- morphism G \u2192 H, with H a Hausdorff topological group, is a topological isomorphism. A topological group (G,\u3c4) is called locally minimal if there exists a neighbourhood V of the identity such that for every Hausdorff group topology \u3c3 64\u3c4 with V 08\u3c3 one has \u3c3 = \u3c4. Minimal groups, as well as locally compact groups, are locally minimal. According to a well known theorem of Prodanov, every subgroup of an infinite compact abelian group K is minimal if and only if K is isomorphic to the group Zp of p-adic integers for some prime p. We find a remarkable connection of local minimality to Lie groups and p-adic numbers by means of the following results extending Prodanov\u2019s theorem: every subgroup of a locally compact abelian group K is locally minimal if and only if either K is a Lie group, or K has an open subgroup isomorphic to Zp for some prime p. In the nonabelian case we prove that all subgroups of a connected locally compact group are locally minimal if and only if K is a Lie group, resolving Problem 7.49 from Dikranjan and Megrelishvili (2014) in the positive

Quotients of locally minimal groups

A topological group G is called locally minimal if there exists a neighbourhood V of 1 in G such that if H is a Hausdorff group and f : G \u2192 H is a continuous isomorphism such that f(V) is a neighbourhood of 1 in H, then f is open. This paper is focused on the study of quotients of locally minimal groups. A topological group G is called locally q-minimal if there exists a neighbourhood V of the identity of G such that whenever H is a Hausdorff group and f : G \u2192 H is a continuous surjective homomorphism such that f(V) is a neighbourhood of 1 in H, then f is open. We find a close connection between locally q-minimality and divisibility, by showing that a dense subgroup of Rn is locally q-minimal if and only if it is divisible. A description of the locally q-minimal subgroups of the n-dimensional torus Tn is also given. Two weaker versions of local q-minimality are proposed \u2013 a topological group G is: (a) locally t-minimal, if all Hausdorff quotients of G are locally minimal; (b) locally q 17-minimal, if there exists a neighbourhood V of 1 in G such that whenever H is a Hausdorff group and f : G \u2192 H is a continuous surjective homomorphism such that f (V ) is a neighbourhood of 1 in H and ker f 86 V , then f is open. While local q-minimality and local t-minimality are preserved by taking quotients, local q 17-minimality fails to have this property (so does not coincide with local t-minimality), yet it has a relevant advantage. By means of an appropriate no- tion of local t-density, one can show that a dense subgroup H of a Hausdorff group G is locally q 17-minimal if and only if G is locally q 17-minimal and H is locally t-dense in G. Similar criterion for local q-minimality is not available (examples are given to show that a topological group with a dense locally q-minimal subgroup need not be locally q-minimal). The interrelations of these three versions of local minimality, as well as their prominence properties are studied in detail

Wideband electromagnetic interference filtering power divider with a wide stopband using the genetic algorithm

This paper proposes a new design of an electromagnetic interference wideband filtering power divider (FPD) with a wide stopband based on the genetic algorithm (GA). A set of data structures is constructed by describing the corresponding connection method between the basic units and their electrical parameters in the three-port design. Then, the GA is used to find the appropriate design topology and electrical parameters, including isolation resistances, to meet FPD specifications by optimizing the data structures. For validation, one prototype is implemented. The results indicate that the new wideband FPD exhibits compact size, sharp roll-off, and good in-band isolations

Particle transfer and fusion cross-section for Super-heavy nuclei in dinuclear system

Within the dinuclear system (DNS) conception, instead of solving Fokker-Planck Equation (FPE) analytically, the Master equation is solved numerically to calculate the fusion probability of super-heavy nuclei, so that the harmonic oscillator approximation to the potential energy of the DNS is avoided. The relative motion concerning the energy, the angular momentum, and the fragment deformation relaxations is explicitly treated to couple with the diffusion process, so that the nucleon transition probabilities, which are derived microscopically, are time-dependent. Comparing with the analytical solution of FPE, our results preserve more dynamical effects. The calculated evaporation residue cross sections for one-neutron emission channel of Pb-based reactions are basically in agreement with the known experimental data within one order of magnitude.Comment: 19 pages, plus 6 figures, submitted to Phys. Rev.

Potential-Mediated Recycling of Copper From Brackish Water by an Electrochemical Copper Pump.

Copper ions (Cu2+ ) disposed to the environment at massive scale pose severe threat to human health and waste of resource. Electrochemical deionization (EDI) which captures ions by electrical field is a promising technique for water purification. However, the removal capacity and selectivity toward Cu2+ are unsatisfying, yet the recycling of the captured copper in EDI systems is yet to be explored. Herein, an efficient electrochemical copper pump (ECP) that can deliver Cu2+ from dilute brackish water into much more concentrated solutions is constructed using carbon nanosheets for the first time, which works based on reversible electrosorption and electrodeposition. The trade-off between the removal capacity and reversibility is mediated by the operation voltage. The ECP exhibits a removal capacity of 702.5 mg g-1 toward Cu2+ and a high selectivity coefficient of 64 for Cu2+ /Na+ in the presence of multiple cations; both are the highest reported to date. The energy consumption of 1.79 Wh g-1 is among the lowest for EDI of copper. More importantly, the Cu species captured can be released into a 20-fold higher concentrated solution. Such a high performance is attributed to the optimal potential distribution between the two electrodes that allows reversible electrodeposition and efficient electrosorption

Temporal and Spectral Properties of the Persistent Radio Source Associated with FRB 20190520B with the VLA

Among more than 800 known fast radio bursts (FRBs), only two, namely FRB 20121102A and FRB 20190520B, are confirmed to be associated with a persistent radio sources (PRS). Here we report evidence of apparent temporal variability in the PRS associated with the bursting FRB 20190520B based on the Karl G. Jansky Very Large Array (VLA) observations taken in 2020 and 2021. Based on the analysis of epoch-to-epoch variability of the PRS at L, S, C, and X band in 1-12 GHz, we detected not only overall marginal variability but also a likely radio flux decrease ($\sim$ 3.2 $\sigma$) between the observations taken in 2020 and 2021 at 3 GHz. Assuming no spectral variation in the PRS during these observations, we found the evidence for an overall broadband radio flux decrease by about 20 percent between the 2020 and the 2021 observations, suggesting that the PRS probably evolves on the yearly time scale. If we attribute the marginal variability at 3 GHz as intrinsic or due to scintillation, the size of potential variable component of the PRS is constrained to be sub-parsec. On the other hand, the size of the PRS can be also constrained to be larger than about 0.22 parsec from the averaged radio spectrum and the integrated radio luminosity in the 1-12 GHz band based on equipartition and self-absorption arguments. We discuss potential origins of the PRS and suggest that an accreting compact object origin might be able to explain the PRS's temporal and spectral properties. Confirmation of variability or flux decline of the PRS would be critical to our understanding of the PRS and its relation to the bursting source.Comment: 12 pages, 3 figures, accepted for publication in Ap