Optical Non-Linearity from Montmorillonite Intercalated with a Chromophore-Containing Dendritic Structure: A Self-Assembly Approach

2008 ◽  
Vol 29 (7) ◽  
pp. 587-592 ◽  
Author(s):  
Yung-Chung Chen ◽  
Tzong-Yuan Juang ◽  
Shenghong A. Dai ◽  
Tzong-Ming Wu ◽  
Jiang-Jen Lin ◽  
...  
Keyword(s):  
Self Assembly ◽  
Dendritic Structure

scholarly journals Crystalline modification of a rare earth nucleating agent for isotactic polypropylene based on its self-assembly

2018 ◽  
Vol 5 (5) ◽  
pp. 180247 ◽  
Author(s):  
Yuanming Zhang ◽  
Tingting Sun ◽  
Wei Jiang ◽  
Guangting Han
Keyword(s):  
Hydrogen Bond ◽  
Rare Earth ◽  
Isotactic Polypropylene ◽  
Self Assembly ◽  
Dendritic Structure ◽  
Nucleating Agent ◽  
The Self ◽  
Structure Evolution ◽  
Crystalline Modification ◽  
Assembly Structure

In this paper, the crystalline modification of a rare earth nucleating agent (WBG) for isotactic polypropylene (PP) based on its supramolecular self-assembly was investigated by differential scanning calorimetry, wide-angle X-ray diffraction and polarized optical microscopy. In addition, the relationship between the self-assembly structure of the nucleating agent and the crystalline structure, as well as the possible reason for the self-assembly behaviour, was further studied. The structure evolution of WBG showed that the self-assembly structure changed from a needle-like structure to a dendritic structure with increase in the content of WBG. When the content of WBG exceeded a critical value (0.4 wt%), it self-assembled into a strip structure. This revealed that the structure evolution of WBG contributed to the K β and the crystallization morphology of PP with different content of WBG. In addition, further studies implied that the behaviour of self-assembly was a liquid–solid transformation of WBG, followed by a liquid–liquid phase separation of molten isotactic PP and WBG. The formation of the self-assembly structure was based on the free molecules by hydrogen bond dissociation while being heated, followed by aggregation into another structure by hydrogen bond association while being cooled. Furthermore, self-assembly behaviour depends largely on the interaction between WBG themselves.

Self-Assembly of Hydrophobic Polybetaine Based on (Tridecyl)aminocrotonate and Methacrylic Acid1, "Высокомолекулярные соединения. Серия С"

2017 ◽  
pp. 74-81
Author(s):  
A. V. Shakhvorostov ◽  
Zh. A. Nurakhmetova ◽  
T. M. Seilkhanov ◽  
Nuraje Nurxat ◽  
S. E. Kudaibergenov
Keyword(s):  
Self Assembly ◽  
Potential Surface ◽  
Dendritic Structure ◽  
Self Assembling ◽  
Maltese Cross ◽  
Surface Enhanced ◽  
Polymeric Chains ◽  
Conformational Properties ◽  
Fractal Patterns ◽  
Self Assembled

Novel polymeric betaine based on tridecylaminocrotonate and methacrylic acid was synthesized by Michael addition reaction. The obtained products were abbreviated as CROtriDA-MAA and with respect to its potassium salt as CROtriDA-MAA-K. The structure of CROtriDA-MAA was established by 1H NMR and FTIR spectroscopy. The hydrodynamic, molecular and conformational properties of CROtriDA-MAA-K in solutions and morphology in solid state were evaluated by methods of GPC, DLS, zeta-potential, surface enhanced ellipsoidal microscopy (SEEC), optical microscopy. Meanwhile, the long alkyl “tails” (tridecyl) located in side polymeric chains are responsible for self-assembling behavior. Several types of self-assembled structures in water at different pH and in water-DMSO mixture were observed. The dendritic structure with wide trunks and few side branches is formed at pH 3. The “Maltese cross-like” aggregates were found at pH 6.5. The tree-like fractal patterns are formed at pH 12. The self-assembled coiled-ribbon-like and tubular-like aggregates were observed in water-DMSO mixtures.

Self-Assembly of Amido-Ended Hyperbranched Polyester Films with a Highly Ordered Dendritic Structure

2014 ◽  
Vol 6 (18) ◽  
pp. 16375-16383 ◽  
Author(s):  
Daohong Zhang ◽  
Zhicai Xu ◽  
Junna Li ◽  
Sufang Chen ◽  
Juan Cheng ◽  
...  
Keyword(s):  
Self Assembly ◽  
Dendritic Structure ◽  
Hyperbranched Polyester

Bottom-Up Fabrication of Optical Metamaterials

2014 ◽  
Vol 910 ◽  
pp. 3-6
Author(s):  
Wei Zhao
Keyword(s):  
Self Assembly ◽  
Dendritic Structure ◽  
Frequency Range ◽  
Focusing Effect ◽  
Optical Metamaterials ◽  
Unit Structure ◽  
Ito Glass ◽  
Tin Oxides ◽  
Ir Frequencies ◽  
Micro Morphology

A metamaterial is an artificially structured material which attains its properties from the unit structure rather than the constituent materials. Here, artificially designed silver dendritic structure was used as basic cells to fabricate metamaterials working at IR frequency range, silver dendritic structure was prepared in the mixture of F127 and PEG, then assembled on glass substrate by self-assembly process and further fabricated into sandwich-like metamaterials with Indium-Tin-Oxides (ITO) glass. Micro-morphology of the dendrites array was examined by scanning electron microscopy. These complex-structured metamaterials exhibit pass-bands at IR frequencies, and show slab focusing effect subsequently.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

The Nature of Rapidly Extracted Phycocyanin from the Blue-Green Alga Plectonema Boryanum

1971 ◽  
Vol 29 ◽  
pp. 366-367
Author(s):  
M. Kessel ◽  
R. MacColl
Keyword(s):  
Self Assembly ◽  
Analytical Ultracentrifugation ◽  
Uranyl Acetate ◽  
The Self ◽  
Major Protein ◽  
Subunit Structure ◽  
Blue Green Alga ◽  
Thin Sections ◽  
Blue Green Algae ◽  
Cacodylate Buffer

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.

Video real-time imaging of artificial membranes during freeze-drying by cryo-electron microscopy

1988 ◽  
Vol 46 ◽  
pp. 16-17
Author(s):  
Alan S. Rudolph ◽  
Ronald R. Price
Keyword(s):  
Real Time ◽  
Self Assembly ◽  
Freeze Drying ◽  
Video Capture ◽  
Drying Process ◽  
Artificial Membranes ◽  
The Past ◽  
Cryo Electron Microscopy ◽  
Spherical Structures ◽  
Capture Techniques

We have employed cryoelectron microscopy to visualize events that occur during the freeze-drying of artificial membranes by employing real time video capture techniques. Artificial membranes or liposomes which are spherical structures within internal aqueous space are stabilized by water which provides the driving force for spontaneous self-assembly of these structures. Previous assays of damage to these structures which are induced by freeze drying reveal that the two principal deleterious events that occur are 1) fusion of liposomes and 2) leakage of contents trapped within the liposome [1]. In the past the only way to access these events was to examine the liposomes following the dehydration event. This technique allows the event to be monitored in real time as the liposomes destabilize and as water is sublimed at cryo temperatures in the vacuum of the microscope. The method by which liposomes are compromised by freeze-drying are largely unknown. This technique has shown that cryo-protectants such as glycerol and carbohydrates are able to maintain liposomal structure throughout the drying process.

Biomimetic materials: An introduction

1992 ◽  
Vol 50 (2) ◽  
pp. 1020-1021 ◽  
Author(s):  
M. Sarikaya ◽  
J. T. Staley ◽  
I. A. Aksay
Keyword(s):  
Self Assembly ◽  
Structural Control ◽  
Hierarchical Structures ◽  
Ceramic Composites ◽  
Advanced Materials ◽  
Length Scale ◽  
Spider Webs ◽  
Biomimetic Materials ◽  
Synthetic Materials ◽  
All Ceramic

Biomimetics is an area of research in which the analysis of structures and functions of natural materials provide a source of inspiration for design and processing concepts for novel synthetic materials. Through biomimetics, it may be possible to establish structural control on a continuous length scale, resulting in superior structures able to withstand the requirements placed upon advanced materials. It is well recognized that biological systems efficiently produce complex and hierarchical structures on the molecular, micrometer, and macro scales with unique properties, and with greater structural control than is possible with synthetic materials. The dynamism of these systems allows the collection and transport of constituents; the nucleation, configuration, and growth of new structures by self-assembly; and the repair and replacement of old and damaged components. These materials include all-organic components such as spider webs and insect cuticles (Fig. 1); inorganic-organic composites, such as seashells (Fig. 2) and bones; all-ceramic composites, such as sea urchin teeth, spines, and other skeletal units (Fig. 3); and inorganic ultrafine magnetic and semiconducting particles produced by bacteria and algae, respectively (Fig. 4).

Interrelationship of the cellular distribution and secretion of regular structure (RS) protein in Bacillus licheniformis nm 105

1992 ◽  
Vol 50 (1) ◽  
pp. 712-713
Author(s):  
Xiaorong Zhu ◽  
Richard McVeigh ◽  
Bijan K. Ghosh
Keyword(s):  
Alkaline Phosphatase ◽  
Bacillus Licheniformis ◽  
Self Assembly ◽  
Gel Electrophoresis ◽  
Culture Supernatant ◽  
Regular Structure ◽  
The Self ◽  
Cellular Distribution ◽  
Structural Protein ◽  
Laboratory Cultures

A mutant of Bacillus licheniformis 749/C, NM 105 exhibits some notable properties, e.g., arrest of alkaline phosphatase secretion and overexpression and hypersecretion of RS protein. Although RS is known to be widely distributed in many microbes, it is rarely found, with a few exceptions, in laboratory cultures of microorganisms. RS protein is a structural protein and has the unusual properties to form aggregate. This characteristic may have been responsible for the self assembly of RS into regular tetragonal structures. Another uncommon characteristic of RS is that enhanced synthesis and secretion which occurs when the cells cease to grow. Assembled RS protein with a tetragonal structure is not seen inside cells at any stage of cell growth including cells in the stationary phase of growth. Gel electrophoresis of the culture supernatant shows a very large amount of RS protein in the stationary culture of the B. licheniformis. It seems, Therefore, that the RS protein is cotranslationally secreted and self assembled on the envelope surface.

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