Narrow Results

The paper studies the effect of temperature ($T$), ($T=300$, 3200, 4000, 5000, 6000, 7000K) at pressure $P=0$GPa; pressure ($P$), ($P=0$, 100, 200, 300, 350, 400GPa) at $T=7000$K and thermal annealing time ($t$), $t=47.8$ps (after 10⁵ steps) at $T=7000$K, $P=400$Gpa) on the structure of MgSiO₃ bulk 3000 atoms by Molecular Dynamics (MD) simulation using Born–Mayer (BM) pair interaction potential and periodic boundary conditions. The structural results are analyzed through the Radial Distribution Function (RDF), the Coordination Number (CN), the angle distribution, size ($l$), total energy of the system ($E_{\mathrm{\text{tot}}}$) and the bonding lengths. The results show that the temperature and pressure had influenced the structural properties of MgSiO₃ bulk and formation process geology of the Earth. In addition, the center of the Earth with $T=7000$K and $P=350$GPa has appearance and disappearance of the Si–Si, Si–O, O–O, Si–Mg, O–Mg, Mg–Mg bonds and SiO₄, SiO₅, SiO₆, MgO₃, MgO₄, MgO₅, MgO₆, MgO₇, MgO₈, MgO₉, MgO${}_{10}$, MgO${}_{11}$, MgO${}_{12}$ angle distributions. When increasing the depth of the Earth’s surface $(h)$ lead to size $(l)$ of MgSiO₃ decreases, total energy of the system ($E_{\mathrm{\text{tot}}}$) increases, position of first peak of Radial Distribution Function (RDF) is $(r)$, height of RDF is $g(r)$ varies greatly with $h$ from $h=0$km to $h=1820$km, gradually decreasing with $h$ from $h=2000$km to $h=3200$km and the smallest structural change with $h>3200$km that shows has influence affects on the geological formation of the Earth.

This paper studies the effect of atoms number $(N)$ of bulk Ag: $N=2916$ atoms (Ag${}_{2916}$), 4000 atoms (Ag${}_{4000}$), 5324 atoms (Ag${}_{5324})$, 6912 atoms (Ag${}_{6912})$ at temperature $T=300$K, 400K, 500K, 600K, 700K, 800K, 900K, 1000K on bulk Ag${}_{5324}$ and annealing time $t$ = 200 ps on the structure and phase transition of Ag bulk by Molecular Dynamics (MD) method with Sutton–Chen (SC) pair interaction potential, periodic boundary conditions. The structural results are analyzed through the Radial Distribution Function (RDF), the total energy of the system ($E_{tot})$, the size $(l)$, the phase transition (determined by the relationship between $E_{tot}$ and $T$), and combined with the Common Neighbors Analysis (CNA) method. The obtained results show that the first peak’s position ($r)$ of the RDF has negligible change value, $r=2.78$Å, which is completely consistent with the experimental results. For bulk Ag, there are always four types of structure: FCC, HCP, BCC, Amor and glass transition temperature $T_g=500$K. When decreasing the temperature, bulk Ag changes from liquid state to crystalline state, when increasing the annealing time at $T_g=500$K, bulk Ag changes from amorphous phase to crystalline phase state, leading to the increase of FCC, HCP, BCC structures and the decrease of Amor structure. The obtained results will be used as guide for future experiments.

The following sections are included:

• Introduction

• Experimental Designs
  • Kratky Block Collimation System
  • Pinhole Collimation System
  • Advanced Polymers Beamline
  • ChemMat CARS Undulator Beamline at the APS
    • Undulator X-Ray Source
    • ChemMat CARS Beamline
    • X-Ray Beam Delivery
    • Beamline Layout

• Theoretical Background
  • Particulate Scattering
  • Nonparticulate Scattering
  • Scattering from Semicrystalline Polymers
  • Analysis from Time Resolved Measurements

• Scientific Examples for Synchrotron Research
  • Supramolecular Structures in Complex Fluids
    • Structures of Polyelectrolyte Surfactant Complexes
    • Block Copolymer in Solution
  • Kinetics of Phase Transition
    • Semistiff Chain Polymers
    • Flexible Chain Polymers and Blends
  • Experiments under Supercritical Conditions
  • Polymers under Deformation
  • In situ Study of Fiber Spinning

• Acknowledgments

• References

Structural homogeneity of type IV silica glass is an important parameter and decides its usability. To characterize this parameter easily and quickly is very important. This paper discussed ways to characterize structural homogeneity of type IV silica glass. Current optical homogeneity test by interferometer, fictive temperature and stress birefringence test were compared at first. Then a new optical homogeneity test based on birefringence and image processing was present and can characterize structural homogeneity of type IV silica glass effectively and easily with low costs.

Graphene as a new carbon material allotropism body has many unique properties. The material structure of graphene is a two-dimensional crystal structure with carbon atom superposition in monolayer mode. This special structures exhibit many unique physical and chemical properties, etc. This paper introduced the special physical and chemical properties of graphene, and reviewed the research progress and applications of graphene in the high-tech fields.