Directly Assembling Ligand-Free ZnO Nanocrystals into Three-Dimensional Mesoporous Structures by Oriented Attachment

2011 ◽  
Vol 50 (12) ◽  
pp. 5841-5847 ◽  
Author(s):  
Yunxin Liu ◽  
Dingsheng Wang ◽  
Qing Peng ◽  
Deren Chu ◽  
Xiangwen Liu ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Oriented Attachment ◽  
Zno Nanocrystals ◽  
Ligand Free ◽  
Mesoporous Structures

Defects in three-dimensional spherical assemblies of Ni-doped ZnO nanocrystals

2009 ◽  
Vol 24 (12) ◽  
pp. 3543-3550 ◽  
Author(s):  
K.C. Barick ◽  
M. Aslam ◽  
Jinsong Wu ◽  
Vinayak P. Dravid ◽  
D. Bahadur
Keyword(s):  
Three Dimensional ◽  
Green Emission ◽  
Transition Metal Ions ◽  
Crystal Defects ◽  
Oriented Attachment ◽  
Structural Defects ◽  
Synthesis Process ◽  
Zno Nanocrystals ◽  
Additional Mode ◽  
Doped Zno

Three-dimensional spherical assemblies of Ni-doped ZnO nanocrystals have been prepared by the solution phase synthesis process. It has been observed that transition metal ions (Zn, Ni) are uniformly distributed in the sample and exist in the +2 oxidation state. Detailed investigation of structural defects formed during the formation of spherical assemblies by oriented attachment of nanocrystals was carried out by high-resolution transmission electron microscope (HRTEM), Raman and photoluminescence (PL) spectroscopy. HRTEM analysis revealed the existence of various crystal defects, such as stacking faults, dislocations, etc. The incorporation of Ni2+ into ZnO structure strongly influences the vibrational and optical properties of the sample due to the increment of defect densities. Compared to the optical phonons of ZnO, additional mode observed at 538 cm−1 in Raman spectra of Ni-doped ZnO could be associated with the incorporation of Ni2+ in Zn2+ site. The increase in PL intensity of green emission with Ni2+ doping indicates the formation of a higher concentration of oxygen vacancy in doped nanostructures.

Self-assembly of birnessite nanoflowers by staged three-dimensional oriented attachment

2017 ◽  
Vol 4 (8) ◽  
pp. 1656-1669 ◽  
Author(s):  
Xinran Liang ◽  
Zixiang Zhao ◽  
Mengqiang Zhu ◽  
Fan Liu ◽  
Lijun Wang ◽  
...  
Keyword(s):  
Self Assembly ◽  
Three Dimensional ◽  
Oriented Attachment ◽  
Attachment Process

Assembly of birnessite nanoflowers via a two-directional oriented attachment process.

scholarly journals Three-dimensional EM structure of the ectodomain of integrin αVβ3 in a complex with fibronectin

2005 ◽  
Vol 168 (7) ◽  
pp. 1109-1118 ◽  
Author(s):  
Brian D. Adair ◽  
Jian-Ping Xiong ◽  
Catherine Maddock ◽  
Simon L. Goodman ◽  
M. Amin Arnaout ◽  
...  
Keyword(s):  
Particle Image ◽  
Three Dimensional ◽  
Integrin Αvβ3 ◽  
Dimensional Structure ◽  
Soluble Complex ◽  
Surface Receptors ◽  
Difference Map ◽  
Transmission Electron ◽  
Ligand Free ◽  
Site Binding

Integrins are αβ heterodimeric cell surface receptors that mediate transmembrane signaling by binding extracellular and cytoplasmic ligands. The ectodomain of integrin αVβ3 crystallizes in a bent, genuflexed conformation considered to be inactive (unable to bind physiological ligands in solution) unless it is fully extended by activating stimuli. We generated a stable, soluble complex of the Mn2+-bound αVβ3 ectodomain with a fragment of fibronectin (FN) containing type III domains 7 to 10 and the EDB domain (FN7-EDB-10). Transmission electron microscopy and single particle image analysis were used to determine the three-dimensional structure of this complex. Most αVβ3 particles, whether unliganded or FN-bound, displayed compact, triangular shapes. A difference map comparing ligand-free and FN-bound αVβ3 revealed density that could accommodate the RGD-containing FN10 in proximity to the ligand-binding site of β3, with FN9 just adjacent to the synergy site binding region of αV. We conclude that the ectodomain of αVβ3 manifests a bent conformation that is capable of stably binding a physiological ligand in solution.

scholarly journals Oriented Attachment Is a Major Control Mechanism To Form Nail-like Mn-Doped ZnO Nanocrystals

Langmuir ◽  
2017 ◽  
Vol 33 (51) ◽  
pp. 14709-14717 ◽  
Author(s):  
Samuel Patterson ◽  
Priyanka Arora ◽  
Paige Price ◽  
Jasper W. Dittmar ◽  
Vijay Kumar Das ◽  
...  
Keyword(s):  
Control Mechanism ◽  
Oriented Attachment ◽  
Zno Nanocrystals ◽  
Doped Zno ◽  
Mn Doped

Unliganded GroEL at 2.8 Å: structure and functional implications

1995 ◽  
Vol 348 (1323) ◽  
pp. 113-119 ◽  
Keyword(s):  
Three Dimensional ◽  
Binding Pocket ◽  
Dimensional Structure ◽  
Outer Diameter ◽  
Central Channel ◽  
Crystal Forms ◽  
Monoclinic Form ◽  
C Terminus ◽  
Ligand Free ◽  
Dyad Symmetry

The three-dimensional structure of the E. coli chaperonin, GroEL, has been determined crystallo-graphically and refined to 2.7 Å in two crystal forms: an orthorhombic form from high salt and a monoclinic form from polyethylene glycol. The former is ligand free, the latter is both liganded with ATP analogues and ligand free. These structures provide a structural scaffold upon which to interpret extensive mutagenesis and biochemical studies. GroEL contains two sevenfold rotationally symmetric rings of identical 547-amino acid subunits. The rings are arranged ‘back-to-back’ with exact dyad symmetry to form a stubby cylinder that is 146 Å high with an outer diameter of about 143 Å. The cylinder has a substantial central channel that is unobstructed for the entire length of the cylinder and has a diameter of about 45 Å except for large bulges that lead into a sevenfold symmetric array of elliptical side windows in each ring. Each subunit is composed of three distinct domains: (i) an ‘equatorial’ domain that contains the N- and C-terminus and the ATP-binding pocket, .(ii) an ‘apical domain’ that forms the opening of the central channel and contains poorly ordered segments that mutational studies implicate in binding unfolded polypeptides and GroES, and (iii) an intermediate domain tht connects the other two domains and may serve to transmit allosteric adjustments.

scholarly journals Ultrafast Three-Dimensional X-ray Imaging of Deformation Modes in ZnO Nanocrystals

Nano Letters ◽  
2017 ◽  
Vol 17 (2) ◽  
pp. 1102-1108 ◽  
Author(s):  
Mathew J. Cherukara ◽  
Kiran Sasikumar ◽  
Wonsuk Cha ◽  
Badri Narayanan ◽  
Steven J. Leake ◽  
...  
Keyword(s):  
Three Dimensional ◽  
X Ray ◽  
Zno Nanocrystals ◽  
X Ray Imaging ◽  
Deformation Modes

Three-Dimensional Cubic Mesoporous Structures of SBA-12 and Related Materials by Electron Crystallography

2002 ◽  
Vol 106 (12) ◽  
pp. 3118-3123 ◽  
Author(s):  
Yasuhiro Sakamoto ◽  
Isabel Díaz ◽  
Osamu Terasaki ◽  
Dongyuan Zhao ◽  
Joaquin Pérez-Pariente ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Electron Crystallography ◽  
Cubic Mesoporous ◽  
Mesoporous Structures
Sign in / Sign up

Export Citation Format

Share Document