Demonstration of three-dimensional lattice connectivities in zeolites by two-dimensional high resolution solid state n.m.r. spectroscopy

1989 ◽  
pp. 1240 ◽  
Author(s):  
Colin A. Fyfe ◽  
Hermann Gies ◽  
Yi Feng
Keyword(s):  
Solid State ◽  
High Resolution ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Dimensional Lattice

High Resolution Microscopy of Multi-Layered Biological Crystals

1982 ◽  
Vol 40 ◽  
pp. 80-83
Author(s):  
H.A. Cohen ◽  
T.W. Jeng ◽  
W. Chiu
Keyword(s):  
High Resolution ◽  
Low Dose ◽  
Three Dimensional ◽  
Data Interpretation ◽  
Two Dimensional ◽  
Biological Objects ◽  
Density Maps ◽  
Density Map ◽  
Complex Crystal ◽  
High Resolution Microscopy

This tutorial will discuss the methodology of low dose electron diffraction and imaging of crystalline biological objects, the problems of data interpretation for two-dimensional projected density maps of glucose embedded protein crystals, the factors to be considered in combining tilt data from three-dimensional crystals, and finally, the prospects of achieving a high resolution three-dimensional density map of a biological crystal. This methodology will be illustrated using two proteins under investigation in our laboratory, the T4 DNA helix destabilizing protein gp32*I and the crotoxin complex crystal.

scholarly journals DISCRETE AND CONTINUUM APPROACHES TO THREE-DIMENSIONAL QUANTUM GRAVITY

1991 ◽  
Vol 06 (39) ◽  
pp. 3591-3600 ◽  
Author(s):  
HIROSI OOGURI ◽  
NAOKI SASAKURA
Keyword(s):  
Gauge Theory ◽  
Moduli Space ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Analogue Model ◽  
Gauge Invariant ◽  
Invariant Functions ◽  
Dimensional Lattice ◽  
Chern Simons ◽  
Dimensional Surface

It is shown that, in the three-dimensional lattice gravity defined by Ponzano and Regge, the space of physical states is isomorphic to the space of gauge-invariant functions on the moduli space of flat SU(2) connections over a two-dimensional surface, which gives physical states in the ISO(3) Chern–Simons gauge theory. To prove this, we employ the q-analogue of this model defined by Turaev and Viro as a regularization to sum over states. A recent work by Turaev suggests that the q-analogue model itself may be related to an Euclidean gravity with a cosmological constant proportional to 1/k2, where q=e2πi/(k+2).

scholarly journals Different Benzendicarboxylate-Directed Structural Variations and Properties of Four New Porous Cd(II)-Pyridyl-Triazole Coordination Polymers

2020 ◽  
Vol 8 ◽  
Author(s):  
Ying Zhao ◽  
Jin Jing ◽  
Ning Yan ◽  
Min-Le Han ◽  
Guo-Ping Yang ◽  
...  
Keyword(s):  
Solid State ◽  
Coordination Polymers ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Gas Sorption ◽  
Structural Variations ◽  
Benzenedicarboxylic Acid ◽  
Topological Framework ◽  
The Stability

Four new different porous crystalline Cd(II)-based coordination polymers (CPs), i. e., [Cd(mdpt)2]·2H2O (1), [Cd2(mdpt)2(m-bdc)(H2O)2] (2), [Cd(Hmdpt)(p-bdc)]·2H2O (3), and [Cd3(mdpt)2(bpdc)2]·2.5NMP (4), were obtained successfully by the assembly of Cd(II) ions and bitopic 3-(3-methyl-2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole (Hmdpt) in the presence of various benzendicarboxylate ligands, i.e., 1,3/1,4-benzenedicarboxylic acid (m-H2bdc, p-H2bdc) and biphenyl-4,4′-bicarboxylate (H2bpdc). Herein, complex 1 is a porous 2-fold interpenetrated four-connected 3D NbO topological framework based on the mdpt− ligand; 2 reveals a two-dimensional (2D) hcb network. Interestingly, 3 presents a three-dimensional (3D) rare interpenetrated double-insertion supramolecular net via 2D ···ABAB··· layers and can be viewed as an fsh topological net, while complex 4 displays a 3D sqc117 framework. Then, the different gas sorption performances were carried out carefully for complexes 1 and 4, the results of which showed 4 has preferable sorption than that of 1 and can be the potential CO2 storage and separation material. Furthermore, the stability and luminescence of four complexes were performed carefully in the solid state.

scholarly journals On inertial-range scaling laws

1996 ◽  
Vol 306 ◽  
pp. 167-181 ◽  
Author(s):  
John C. Bowman
Keyword(s):  
Steady State ◽  
High Resolution ◽  
Scaling Laws ◽  
State Energy ◽  
Three Dimensional ◽  
Inertial Range ◽  
Energy Spectra ◽  
Two Dimensional ◽  
Unified Framework ◽  
Asymptotic Nature

Inertial-range scaling laws for two- and three-dimensional turbulence are re-examined within a unified framework. A new correction to Kolmogorov's k−5/3 scaling is derived for the energy inertial range. A related modification is found to Kraichnan's logarithmically corrected two-dimensional enstrophy-range law that removes its unexpected divergence at the injection wavenumber. The significance of these corrections is illustrated with steady-state energy spectra from recent high-resolution closure computations. Implications for conventional numerical simulations are discussed. These results underscore the asymptotic nature of inertial-range scaling laws.

A new two-dimensional managnese(II) coordination polymer constructed by 2,2′-(1,2-phenylene)bis(1H-imidazole-4,5-dicarboxylate)

2018 ◽  
Vol 74 (5) ◽  
pp. 599-603 ◽  
Author(s):  
Yan-Ju Liu ◽  
Di Cheng ◽  
Ya-Xue Li ◽  
Xiang-Ru Meng ◽  
Huai-Xia Yang
Keyword(s):  
Solid State ◽  
Coordination Polymer ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Coordination Geometry ◽  
Two Dimensional ◽  
Carboxylate Ligands ◽  
Rich Variety ◽  
Distorted Octahedral ◽  
Solvothermal Conditions

In recent years, N-heterocyclic carboxylate ligands have attracted much interest in the preparation of new coordination polymers since they contain N-atom donors, as well as O-atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. A new two-dimensional coordination polymer, namely poly[[μ3-2,2′-(1,2-phenylene)bis(4-carboxy-1H-imidazole-5-carboxylato)-κ6 O 4,N 3,N 3′,O 4′:O 5:O 5′]manganese(II)], [Mn(C16H8N4O8)] n or [Mn(H4Phbidc)] n , has been synthesized by the reaction of Mn(OAc)2·4H2O (OAc is acetate) with 2,2′-(1,2-phenylene)bis(1H-imidazole-4,5-dicarboxylic acid) (H6Phbidc) under solvothermal conditions. In the polymer, each MnII ion is six-coordinated by two N atoms from one H4Phbidc2− ligand and by four O atoms from three H4Phbidc2− ligands, forming a significantly distorted octahedral MnN2O4 coordination geometry. The MnII ions are linked by hexadentate H4Phbidc2− ligands, leading to a two-dimensional structure parallel to the ac plane. In the crystal, adjacent layers are further connected by N—H...O hydrogen bonds, forming a three-dimensional structure in the solid state.

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