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A library of novel π‐extended porphyrin‐hexabenzocoronene (HBC) architectures is presented. Two distinct synthetic pathways were utilized to obtain either phenyl‐ or HBC‐fused compounds. Absorption experiments reveal the species’ exciting photophysical and optoelectronic properties. Depending on the degree of π‐extension, the number of porphyrins, and their relative position, a decisive change in shape, panchromatic broadening, and red‐shifting of the absorption curves is observed. Theoretical studies give more profound insight into the molecule's electronic structures, showing vast decreases in HOMO‐LUMO energy gaps. [ABSTRACT FROM AUTHOR]

Nuclear fusion is understood as an energy reaction that does not emit greenhouse gases, and it has been considered as a long-term source of low-carbon electricity that is favourable to curtail rapid climate change. Fusion offers a pathway to resolve energy security and the unequal distribution of energy resources since seawater is its ultimate fuel source and a few grams of fuel can generate mega kilowatts of power. The development and testing of new materials and technologies are unceasing to achieve the net fusion energy through national and international collaboration as well as private partnerships. The ever-growing number of research works report various designs and magnet-based fusion devices, such as stellarators, lasers, and tokamaks. This article provides an overview on the utilization of nuclear energy as a clean energy source, as well as the strategies and progress towards establishing successful commercial fusion energy to the grid and transition to a reliable clean energy source. The overview focuses on the fusion nuclear development in five major countries, UK, US, China, Japan, and Russia. Identified technical and financial challenges are also described at the end of this article. The International Thermonuclear Experimental Reactor (ITER) has been an international reference program for fusion energy development and most developed countries with nuclear development capacity are aiming to complete their in-house fusion energy facilities in parallel to ITER. Many fusion programs are finishing the conceptual design and shifting into the phase of engineering design for the planned DEMO fusion facilities. The significant challenges were identified from the perspective of device efficiency and robustness, sustainable funding, and facility maintenance and safety, which must be addressed diligently to realize fusion energy as alternative clean energy that mitigates climate change and supports the goals of energy security. [ABSTRACT FROM AUTHOR]

Semiconductor-based neutron-detectors are characterized by small size, high energy-resolution, good spatial resolution, and stable response (at the depletion voltage). Consequently, these neutron-detectors are important for the fields of nuclear proliferation prevention, oil exploration, monitoring neutron-scattering experiments, cancer treatments, and space radiation effect research. However, there are some well-known problems for conventional silicon-based neutron detectors: low neutron-detection efficiency and limited resistance to radiation. Therefore, critical improvements are needed to enable sufficiently effective and practical neutron detection. To address these problems, direct-conversion neutron detectors as well as wide bandgap semiconductor-based detectors have been developed and studied intensely during the past years. Significant progress with respect to detection efficiency, radiation resistance, and room temperature operation was achieved. This paper reviews the latest research highlights, remaining challenges, and emerging technologies of direct-conversion neutron detectors as well as wide-bandgap semiconductor neutron detectors. This compact review serves as a reference for researchers interested in the design and development of improved neutron detectors in the future. [ABSTRACT FROM AUTHOR]

The capture cross section, the fusion cross section, and the quasi-fission yield producing symmetric fragments ( ACN/2 ± 20u ) in the 48 Ca+ 238 U reaction are analyzed by the multidimensional Langevin equation taking account of the surface friction effect. From the experimental data, the strength of the tangential friction has been determined. It is presented that tangential friction increases in proportional to the power of the relative velocity of the projectile and the target.

In this paper, the possible ways of forming the midi-fullerene isomers, namely C22, C24 and C26, have been systematized. Three simplest mechanisms for their synthesizing are known. They are the fusion of carbon cupolas having the same symmetry; the fusion of fullerenes having compatible symmetry; embedding carbon dimers into initial fullerenes. The structures with minimal energy were formed through the use of the third mechanism retaining the topological three-fold symmetry. The symmetry order of studied fullerenes changed from the third to the sixth. The geometric modeling carried out in conjunction with the analysis of structures’ formation energies gives researchers a clear idea of the structure of the resulting fullerenes.

With experimental facilities being developed globally, producing superheavy nuclei using heavy-ion collision has become feasible, which is essential for exploring charge and mass limits of nuclei and understanding the r-process in nuclear astrophysics. Fusion reactions are crucial for the synthesis of superheavy nuclei, yet only neutron-deficient superheavy nuclei get produced due to the limited neutron number of stable beams. Recent experiments suggest that multinucleon transfer reactions are promising for producing new neutron-rich superheavy nuclei. As a result, transport models are required for extracting physics information from these experiments and making predictions about incident energies and projectile-target combinations, to synthesize new super-heavy nuclei. In this article, we introduce the development of transport models such as the dinuclear system (DNS) model, quantum molecular dynamics (QMD) type model, Boltzmann type model, and Time-dependent Hatree-Fock (TDHF) type model, and conclude with their latest applications in the synthesis of superheavy nuclei, especially in fusion reactions and multinucleon transfer reactions. In addition, various international large-scale scientific facilities, as well as their scientific objectives, and future plans, are also summarized.

One of the interesting topics in nuclear reactions is a study about reaction cross section between the interacting nuclei. For calculating fusion cross section, the Glas-Mosel formula has been proven successfully in explaining the experimental results of fusion cross section. In this study, the fusion cross sections of O16+O16 reaction were calculated by using modified Glas-Mosel formula. The energies were set at 10≤𝐸≤40 MeV. The potential of interacting nuclei was approached by using Woods-Saxon potential. In numerical process, the differential equations were solved by using finite different method and optimization process was performed by using Nelder-Mead method. Good agreement between the experimental and this study results has been achieved successfully. Referring those results above, it can be indicated that the modified Glas-Mosel formula has good capability to explain the experimental results of fusion reaction of light nuclei. It can be a useful tool in explaining the experimental results or in predicting fusion cross section of light nuclei.

The height of the barrier between the interacting nuclei is one of the interesting topics in nuclear reaction, especially in charged-particle nuclear reactions. Wong formula is one method that can be used to perform such study, especially about fusion cross section. Therefore, a study about fusion cross sections of some light nuclei with Wong formula becomes very interesting to be performed. In this study, the fusion cross sections of 12C+12C and 16O+16O reactions have been calculated by using Wong formula at 12

The extension of the aromatic π‐system of porphyrins is a powerful method to alter their optoelectronic properties. Herein, aryl substituents were fused to porphyrin cores by Scholl oxidation reactions that selectively produced mono‐ and doubly‐fused porphyrins in yields of up to 69 %. Several different aryl substituents attached to the porphyrin were investigated with respect to their reactivity under Scholl conditions. The fused products were fully characterized, i.e., by UV/Vis absorption spectroscopy, which showed drastic changes in the electronic features. Insight into the solid‐state behavior was obtained by X‐ray crystallography. Our approach represents a novel option for the late‐stage functionalization of porphyrin‐based compounds. [ABSTRACT FROM AUTHOR]

In this paper, we theoretically investigate 21 projectile-target combinations of stable isotopes for the pre-synthesis parameters and production cross sections of the unknown superheavy 309,312126 nuclei. It is found that 61Ni + 248Cf and 64Ni + 248Cf combinations are the best candidates for the synthesis of the 309,312126 isotopes due to their largest cross sections of 0.03 and 3.6 pb, respectively. Besides, the results in the present and previous works indicate that the uncertainty, from pb to zb, in the synthesis cross sections of superheavy nuclei should be narrowed for a decision of measurements using the presently available facilities. This study, thus, provides valuable data for the synthesis of 126th element. [ABSTRACT FROM AUTHOR]

We have studied the α-decay chains of superheavy nuclei Z = 123 in the range 265 ≤ A ≤ 316. The nuclei 303–308123 were found to have longer half-lives and hence could be detected them if synthesized in a laboratory. After identifying the possible isotopes, we have identified the most probable projectile–target combinations by studying the fusion cross section, evaporation residue cross section, compound nucleus formation probability (PCN) and survival probability (PSurv) of different projectile–target combinations to synthesize superheavy element Z = 123. The selected most probable projectile–target combination to synthesize superheavy nuclei with Z = 123 is Mn + Cf. We hope that our predictions may be guide for the future experiments in the synthesis of new superheavy element Z = 123. [ABSTRACT FROM AUTHOR]

Analysis of the fusion reactions of halo nuclei is one of the important subjects of nuclear physics. In addition, temperature-dependent analysis of fusion cross-sections of these nuclei is a deficient topic in the literature. In order to overcome this deficiency, the fusion cross-sections of 6He, 8He and 1 1 Li which are the most important halo nuclei are analyzed by using both temperature-independent potential and temperature-dependent potential. All the theoretical results are compared with each other as well as the experimental data. It is seen that the results of temperature-independent potential are in good agreement with the data while the temperature-dependent potential has a significant impact on the fusion cross-sections. Finally, the changes with the temperature of both real and nuclear potentials of all the reactions are investigated. [ABSTRACT FROM AUTHOR]

Fusion reactions 40Ar + 116Sn, 40Ar + 122Sn and 40Ca + 124Sn have been examined by employing coupled channel (CC) approach using code-CCFULL. Here we aim to investigate the influence of multi-neutron transfer channels in addition to coupling of collective excitations on sub-barrier fusion enhancement. Incorporation of inelastic excitations alone reproduced the experimental results for 40Ar + 116Sn system while for 40Ar + 122Sn contribution of 2n transfer channel is required to explain the experimental data. However, CC calculations with 2n transfer could not explain the enhancement at sub-barrier energies for 40Ca + 124Sn system. Therefore, the empirical coupled channel (ECC) calculations have been carried out to include the effect of multi-neutron transfer channels and it is found that the incorporation of sequential 4n transfer channel reproduced the experimental results in entire energy region. Nevertheless, it is observed that multi-neutron transfer coupling significantly contributed in raising the sub-barrier fusion cross sections particularly for the reactions where colliding partners are spherical. Importantly, it is also found that transfer of even number of neutrons play dominating role in sub-barrier fusion enhancement. [ABSTRACT FROM AUTHOR]

The fusion evaporation residue (ER) cross-sections σ x n for the decay of compound nucleus (CN) 2 5 2 , 2 5 4 , 2 5 5 , 2 5 6 No ∗ via 1 n –4 n decay channels, synthesized in 2 0 4 , 2 0 6 , 2 0 7 , 2 0 8 Pb + 4 8 Ca reaction, are studied, including deformations β 2 i for cold-optimum orientations 𝜃 i at various 4 8 Ca excitation energies of E ∗ = 2 0 to 45 MeV. For the nuclear interaction potentials, we use the Skyrme energy density functional (SEDF)-based on semi-classical extended Thomas Fermi (ETF) approach under frozen density approximation on our earlier study of fusion ER cross-section for the decay of 2 5 2 , 2 5 4 − 2 5 6 No ∗ , via 1 n –4 n decay channels synthesized in 2 0 4 , 2 0 6 − 2 0 8 Pb + 4 8 Ca reaction based on the Dynamical cluster-decay model (DCM) using the pocket formula for nuclear proximity potential in which the above reaction was investigated by using hot-optimum orientations. In this work the above reaction has been investigated in two parts, in the first part, E ∗ < 2 5 MeV is used for cold elongated configurations and in the second part, E ∗ > 2 5 MeV is used for hot compact configurations. The Skyrme forces used here are the old SIII, and new GSkI and KDE0(v1) given for both normal and isospin-rich nuclei, with densities added in frozen density approximation. Interestingly, independent of the Skyrme force used, the DCM gives an excellent fit within one-parameter fitting of Δ R to the measured data on fusion ER for cold fusion. Of all the three Pb-isotopes and three E ∗ considered, at each E ∗ , the Δ R is largest for compound system with mass numbers 256 and 254, and smallest for 252, which means that the neutrons emission occur earliest for 256, then 255 followed by 254 and finally for 252, in complete agreement with experimental data. The possible fusion–fission (ff) and quasi-fission (qf) mass-regions of fragments on DCM are also predicted. The DCM with Skyrme forces is further used to look for all the possible target-projectile (t - p) combinations forming the "cold" CN 2 5 4 No ∗ at the CN excitation energy of E ∗ for "optimum cold" configurations. The fusion ER cross-sections, for the proposed new reactions in synthesizing the CN 2 5 4 No ∗ , are also estimated for the future experiments. [ABSTRACT FROM AUTHOR]

A semiclassical and full quantum mechanical approaches have been used to study the effect of channel coupling on the calculations of the total fusion reaction cross section , the fusion barrier distribution and the reaction probability for the systems 11B+237Np, 15N+54Fe and 58Ni +54Fe. The semiclassical approach used in the present work based on the method of the Alder and Winther for Coulomb excitation. The full quantum mechanical approach was based on solving the time dependent Schrödinger equationincluding the coupling effect. A comparison of our semiclassical calculations and full quantum mechanical calculations with the corresponding experimental data shows good agreement, above and below the Coulomb barrier.