We mainly focus on the effects of small changes of parameters on the dynamics of charged particles around Kerr black holes surrounded by an external magnetic field, which can be considered as a tidal environment. The radial motions of charged particles on the equatorial plane are studied via an effective potential. It is found that the particle energies at the local maxima values of the effective potentials increase with an increase in the black hole spin and the particle angular momenta, but decrease with an increase of one of the inductive charge parameter and magnetic field parameter. The radii of stable circular orbits on the equatorial plane also increase, whereas those of the innermost stable circular orbits decrease. On the other hand, the effects of small variations of the parameters on the orbital regular and chaotic dynamics of charged particles on the non-equatorial plane are traced by means of a time-transformed explicit symplectic integrator, Poincaré sections and fast Lyapunov indicators. It is shown that the dynamics sensitivity depends on small variations in the inductive charge parameter, magnetic field parameter, energy, and angular momentum. Chaos occurs easily as each of the inductive charge parameter, magnetic field parameter, and energy increases but is weakened as the angular momentum increases. When the dragging effects of the spacetime increase, the chaotic properties are not always weakened under some circumstances.

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Organic−inorganic hybrid perovskites with temperature-dependent dual emission are attracting more attention due to their promising application in fluorescence intensity ratio technology. Herein, we report a Cu-based organic−inorganic hybrid perovskite (BDA)Cu 2 Br 4 (BDA = C 4 H 12 N 2 2+ ) with dimeric clusters ([Cu 2 Br 6 ] 4− ) and organic cations (BDA) periodically arranged in a one-dimensional structure. This structure enables lattice selftrapping and strong coupling between electrons and phonons. The difference in the degree of lattice distortion affected by the temperature decrease leads to the mutual competition between two different self-trapped excitons, thus causing the two self-trapped emissions, resulting in the emission changes from the blue light to the orange-red light. Furthermore, these change in emission color can reverse while the temperature increases. This property potentially enables applications in temperature sensing, blue LEDs, and solid-state lighting.

Environmental dependence of male sterility may sometimes result in residual fertility under 'sterility conditions', causing hybrid-seed contamination risk. An experiment was conducted to assess the risk factor and methods to increase hybrid-seed purity in a thermosensitive male-sterile tomato mutant, T-4, whose fertility is partially restored in autumn, but largely remains sterile in spring, with some residual fertility. Examination of pollen germination and the subsequent pollen-tube growth in vitro and on stigma revealed that a small proportion of the T-4 pollen was viable, with 10-20% germination, while normal pollen from 'Tiny Tim' had 60-85% germination 3-6 h after pollination. A stable male-sterile mutant T-3, whose pollen development collapses at the microspore stage, was pollinated with T-4 pollen followed by normal 'Tiny Tim' pollen with time lags of 2, 4, and 8 h. Concurrently, the T-4 mutant was self-pollinated by hand followed by normal pollen from an inbred line (M) with time lags of 2, 4, 8, 24, and 48 h. The progeny was scored for contamination based on differences in leaf characteristics. The percentage of T-4 seedlings (narrow leaved) in the F 1 progeny was lowest at 2 h (0.2-6.3%), highest at 8 h (16.9-17.7%) and declined at 24 h-48 h (13.5-10.3%) time lag. The contamination rate was extremely low when pollination was done with normal pollen at (0.4%) and 24 h after (1.4%) anthesis without prior hand pollination with T-4 pollen. It was concluded that with pollination timing soon after anthesis, the T-4 mutant could be effectively applied in a two-line hybrid-seed production system with lower roguing cost of undesirable seedlings as opposed to the conventional three-line system.

We studied the space-time properties of the triangular symmetric black hole in the case of extreme RN black hole. Because the neutral test particle is only affected by space-time in the curved space-time, we chose the triangular symmetric black hole as the model with which to study the motion of the test particle in this case. The curvature tensor and curvature scalar were calculated by giving the metric and the Christoffel Symbol, and then the kinematics equation of the test particle was obtained and analyzed by using these quantities. Then we analyzed the relationship between the coordinate distance and the inherent distance, the relationship between the coordinate time and the inherent time, the inherent velocity and the coordinate velocity of light, and then verified the correctness of general relativity. Next, the one-dimensional effective potential and two-dimensional effective potential of the system under different separation distances were analyzed. Finally, we analyzed and explored the innermost stable circular orbit, calculated all the Lagrange points under this model, and expounded some applications of circular orbit in astrophysics.