Tuned Transport Path of Perovskite MAPbI3-based Memristor Structure

In this study, the features of resistive random access memory (RRAM) employing a straightforward Cr/MAPbI₃/FTO three-layer structure have been examined and clarified. The device displays various resistance switching (RS) behavior at various sweep voltages between 0.5 and 5 V. The RS effect has a conversion in the direction of the SET and RESET processes during sweeping for a number of cycles at a specific voltage. The directional change of the RS processes corresponds to the dominant transition between the generation/recombination of iodide ion and vacancy in the MAPbI₃ perovskite layer and the electrochemical metallization of the Cr electrode under the influence of an electric field, which results in the conductive filament (CF) formation/rupture. At each stage, these processes are controlled by specific charge conduction mechanisms, including Ohmic conduction, space-charge-limited conduction (SCLC), and variable-range hopping (VRH). By identifying the biased voltage and the quantity of voltage sweep cycles, one can take a new approach to control or modulate the pathways for effective charge transport. This new approach is made possible by an understanding of the RS characteristics and the corresponding mechanisms causing the variation of RS behavior in the structure.     

Hydrazine bisalane is a potential compound for chemical hydrogen storage. A theoretical study

Electronic structure calculations suggest that hydrazine bisalane (AlH(3)NH(2)NH(2)AlH(3), alhyzal) is a promising compound for chemical hydrogen storage (CHS). Calculations are carried out using the coupled-cluster theory CCSD(T) with the aug-cc-pVTZ basis set. Potential energy surfaces are constructed to probe the formation of, and hydrogen release from, hydrazine bisalane which is initially formed from the reaction of hydrazine with dialane. Molecular and electronic characteristics of both gauche and trans alhyzal are determined for the first time. The gauche hydrazine bisalane is formed from starting reactants hydrazine + dialane following a movement of an AlH(3) group from AlH(3)AlH(3)NH(2)NH(2) rather than by a direct attachment of a separate AlH(3) group, generated by predissociation of dialane, to AlH(3)NH(2)NH(2). The energy barriers for dehydrogenation processes from gauche and transalhyzal are in the range of 21-28 kcal mol(-1), which are substantially smaller than those of ca. 40 kcal mol(-1) previously determined for the isovalent hydrazine bisborane (bhyzb) system. H(2) release from hydrazine bisalane is thus more favored over that from hydrazine bisborane, making the Al derivative an alternative candidate for CHS.     

Syntheses and characterizations of thiolato-functionalized N-heterocyclic carbene Pd(II) complexes with normal and mesoionic binding modes

The thiolato-bridged dimeric Pd(II) NHC complex 1 has been synthesized from the reaction of thioester-functionalized imidazolium salt B and Pd(OAc)(2). The isolation of its interesting constitutional isomer 2 bearing both classical C(2)-bound and mesoionic C(4)-bound ligands coordinating to two different metal centers in the same complex allowed for a direct comparison of these isomeric carbenes. Reactivity studies of 1 with NaSCH(CH(3))(2) and NaBF(4) afforded the tetranuclear compound 3 with a [Pd(4)S(4)] macrocycle. All complexes have been fully characterized by multinuclei NMR spectroscopies, ESI mass spectrometry and X-ray diffraction analysis.     

On formulas for the velocity of Stoneley waves propagating along the loosely bonded interface of two elastic half-spaces

Formulas for the velocity of Stoneley waves propagating along the loosely bonded interface of two isotropic elastic half-spaces are derived using the complex function method. The derivation also shows that if a Stoneley wave exists, then it is unique. By using the obtained formulas, we can easily reproduce the numerical results previously obtained by Murty [G. S. Murty, Phys. Earth Planet. Interiors 11 (1975), 65–79.] by directly solving the secular equation.     

Some results on the large-time behavior of weakly coupled systems of first-order Hamilton–Jacobi equations

Systems of Hamilton–Jacobi equations arise naturally when we study optimal control problems with pathwise deterministic trajectories with random switching. In this work, we are interested in the large-time behavior of weakly coupled systems of first-order Hamilton–Jacobi equations in the periodic setting. First results have been obtained by Camilli et al. (NoDEA Nonlinear Diff Eq Appl, 2012) and Mitake and Tran (Asymptot Anal, 2012) under quite strict conditions. Here, we use a PDE approach to extend the convergence result proved by Barles and Souganidis (SIAM J Math Anal 31(4):925–939 (electronic), 2000) in the scalar case. This result permits us to treat general cases, for instance, systems of nonconvex Hamiltonians and systems of strictly convex Hamiltonians. We also obtain some other convergence results under different assumptions. These results give a clearer view on the large-time behavior for systems of Hamilton–Jacobi equations.     

Adjoint methods for static Hamilton�CJacobi equations

We use the adjoint methods to study the static Hamilton?CJacobi equations and to prove the speed of convergence for those equations. The main new ideas are to introduce adjoint equations corresponding to the formal linearizations of regularized equations of vanishing viscosity type, and from the solutions ?? ^?? of those we can get the properties of the solutions u of the Hamilton?CJacobi equations. We classify the static equations into two types and present two new ways to deal with each type. The methods can be applied to various static problems and point out the new ways to look at those PDE.     

Coupled Solitons for Quantum Communication and Metrology in the Presence of Particle Dissipation

Journal of Russian Laser Research - Bright solitons represent natural information carriers for optical communication. However, particle losses create serious barriers to soliton implementation in...     

Study of the isomeric ratios in photonuclear reactions of natural indium induced by bremsstrahlungs with end-point energies in the giant dipole resonance region

We have determined the isomeric ratios in ¹¹³In(γ, n)^112m,g In and ¹¹³In(γ, 2n)^111m,g In photonuclear reactions of natural indium induced by bremsstrahlungs with end-point energies in the giant dipole resonance (GDR) region. The investigated samples were irradiated at the electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, Dubna. The gamma spectra of the samples irradiated were measured with a spectroscopic system consisting of an 8192-channel analyzer and a high-energy resolution (180 keV at gamma ray 1332 keV of ⁶⁰Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors. For both the mentioned reactions, the isomeric ratios in the bremsstrahlung energy range from 19 to 24 MeV in this work are new measurements.     

PEGylated poly(amidoamine) dendrimers-based drug loading vehicles for delivering carboplatin in treatment of various cancerous cells

Journal of Nanoparticle Research - Highly ordered TiO2 nanotube arrays (TiO2 NTs) were synthesized by anodization method using a titanium foil and further modified with nanoparticles...