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Computationally Guided Redesign of a Heme-free Cytochrome with Native-like Structure and Stability
Not provided.
Structure and Stability of Core–Shell Cu–Pt Nanoparticles for Catalytic Applications
Not provided.
Molecular Coordination, Structure, and Stability of Metal-Polyphosphate Complexes Resolved by Molecu
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Thermal stability and structure of glyceraldehyde-3-phosphate dehydrogenase from the coral Acropora
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“Breathing” organic cation to stabilize multiple structures in low-dimensional Ge-, Sn-, and Pb-based hybrid iodide perovskites
Low-dimensional hybrid inorganic–organic perovskites are excellent candidates for stable optoelectronic devices. The dimensionality of these perovskites depends largely on the organic and inorganic compositions, as well as the synthetic conditions. We report five new hybrid iodides, (ETU) 4 Ge 5 I 18 , (ETU)GeI 4 , (ETU)SnI 4 , (ETU)PbI 4 , and (ETU) 3 Pb 2 I 10 using only one type of organic cation, namely, S-(2-aminoethyl)isothiouronium (ETU). (ETU)GeI 4 and (ETU)SnI 4 belong to the (110)-oriented structure-type with “3 × 3” sawtooth corrugated layers and crystallize in a structure with the orthorhombic space group Pbca. (ETU) 4 Ge 5 I 18 crystallizes in a structure with the triclinic space group P$\bar{1}$with combining macron], featuring a 2D layered structure with combinations of corner, edge, and face-sharing [GeI 6 ] octahedra. For the Pb-based series, (ETU)PbI 4 has the conventional (100) – oriented 2D type whereas (ETU) 3 Pb 2 I 10 has a unique 0D structure. Remarkably, the unstable 2D orange-phase (ETU)PbI 4 transforms to a stable 0D yellow phase (ETU) 3 Pb 2 I 10 , accompanied by the reduction of the C–S–C angle of the organic cation ETU. The optical band gaps are largely regulated by the diverse types of structure and are in the range of 1.8 eV to 2.8 eV. (ETU)SnI 4 is the only material showing notable photoluminescence at room-temperature. Our work showcases the flexibility of the organic cation in determining the structural dimensionality and provides a new strategy in generating new hybrid materials.
Monolayer 1T-LaN 2 : Dirac spin-gapless semiconductor of p -state and Chern insulator with a high Chern number
Two-dimensional transition-metal dinitrides have attracted considerable attention in recent years due to their rich magnetic properties. Here, we focus on rare-earth-metal elements and propose a monolayer of lanthanum dinitride with a 1T structural phase, 1T-LaN 2 . Using first-principles calculations, we systematically investigated the structure, stability, magnetism, and band structure of this material. It is a flexible and stable monolayer exhibiting a low lattice thermal conductivity, which is promising for future thermoelectric devices. Here, the monolayer shows the ferromagnetic ground state with a spin-polarized band structure. Two linear spin-polarized bands cross at the Fermi level forming a Dirac point, which is formed by the p atomic orbitals of the N atoms, indicating that monolayer 1T-LaN 2 is a Dirac spin-gapless semiconductor of p-state. When the spin–orbit coupling is taken into account, a large nontrivial indirect bandgap (86/354 meV) can be opened at the Dirac point, and three chiral edge states are obtained, corresponding to a high Chern number of C = 3, implying that monolayer 1T-LaN 2 is a Chern insulator. Importantly, this kind of band structure is expected to occur in more monolayers of rare-earth-metal dinitride with a 1T structural phase.
Structure and stability of 2H[alpha]-MoS[subscript 2] at high pressure and low temperatures
Abstract not provided
THE GROWTH AND DECAY OF HOT SPOTS AND THE RELATION BETWEEN STRUCTURE AND STABILITY
Growth and decay of hot spots - estimation of critical conditions for explosion occurence
On the stability and structure of shock waves in interplanetary space
Structure of interplanetary shock waves formed by interaction of geomagnetic field and solar wind - earth bow shock
Large space erectable structures.
Large space erectable structures rigidity, stiffness, thermal stability, structural efficiency and integrity
Structural dynamics, stability, and control of helicopters
The dynamic synthesis of a helicopter is reported. The method of approach is a variation of the component mode synthesis in the sense that it regards the aircraft as an assemblage of interconnected substructures. The equations of motion are derived in general form by means of the Lagrangian formulation in conjunction with an orderly kinematical procedure that takes into account the superposition of motion of various substructures, thus circumventing constraint problems.
The Influence of Gravity on Nucleation, Growth, Stability and Structure in Crystallizing Colloidal Suspensions
Our goal is to understand the dynamics of particles within colloidal crystals. In particular, we focus on the influence of the cell walls and gravity on the particle dynamics. In this study, we will use a novel light scattering experiment, known as diffusing wave spectroscopy, to probe particle motions in turbid suspensions. This is a noninvasive experimental probe of interparticle dynamics.
In-Flight Suppression of a De-Stabilized F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System
Adaptive Augmenting Control (AAC) has been developed for NASA's Space Launch System (SLS) family of launch vehicles and implemented as a baseline part of its flight control system (FCS). To raise the technical readiness level of the SLS AAC algorithm, the Launch Vehicle Adaptive Control (LVAC) flight test program was conducted in which the SLS FCS prototype software was employed to control the pitch axis of Dryden's specially outfitted F/A-18, the Full Scale Advanced Systems Test Bed (FAST). This presentation focuses on a set of special test cases which demonstrate the successful mitigation of the unstable coupling of an F/A-18 airframe structural mode with the SLS FCS.
Complex Intergrowths of Non-Stoichiometric Defect-Structured Hibonite and Al-Rich Spinel in an Allende Ca-Al-Rich Inclusion
Hibonite is a primary ultra-refractory mineral occurring in many Ca-Al-rich inclusions (CAIs) and is predicted to condense as the second major phase from a cooling gas of solar composition. Our previous microstructural studies of hibonite in carbonaceous chondrites revealed its unique microstructures consisting of numerous defects that contain Mg-enriched, wider spinel blocks in stoichiometric hibonite. Han, J. et al. [2 items] demonstrated experimentally that defect-structured hibonites can grow easily in the presence of minor Mg and are kinetically more stable than equilibrium assemblages predicted by thermodynamic calculations. However, a thermo-dynamic vs. structural stability of defect-structured hibonite relative to other early-condensed Al-rich phases such as corundum, grossite, and spinel remains poorly constrained. Here, we present the results of atomic resolution TEM (Transmission Electron Microscopy) imaging of hibonite in a compact Type A CAI in the Allende CV3 chondrite in order to better understand the crystal structure and chemistry of defect-structured hibonite and its associated Al-rich phases, especially non-stoichiometric, Al-rich spinel, in the context of the formation of first refractory solids in the early solar nebula.