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Electrospinning of Poly(lactic acid)/Poly(lactic acid-co-lysine) Blend Junyan YAO 1,a *, Yujie LI 1,b, Zhi DU 1,c and Minghe CHEN 1,d 1Department of Applied Chemistry, Northwestern Polytechnical University, China ayaojunyan@nwpu.edu.cn, bleaj808@126.com, cduzhixuesheng@163.com, dchen11891@163.com Keywords: Poly(lactic acid), Poly(lactic acid-co-lysine), blend, electrospinning, morphology Abstract.
Viscosity, conductivity and surface tension of electrospinning solution had critical effect on the structures of the electrospun blend.
The morphological structure and properties of electrospun PLA can be changed by copolymerization, blending or composite modifications.
Solution parameters (concentration, viscosity, surface tension and conductivity, etc.) had great influence on the morphology and structure of the electrospun products.
With the decrease of PLA/PLL concentration, the structure of the spinning products transformed from fiber to fusiform and spherical.

The structure of the dry gel as prepared was characterized by X-ray Diffraction(XRD), Fourier Transform Infrared Spectroscopy(FT-IR) and Scanning electron microscope(SEM).
As a result, amorphous structure is proved.
Hao: Colloid Chemistry, edited by Chemical Industry, Bei Jing(2005), in press.

Results and Discussion Crystal structure of Mg-Al-CO3 LDHs.
This is commonly used for the description of LDHs structures.
In photo(b), many small sheets combine flower structures.
XRD was used to confirm the structure.
Vistad, Journal of Materials Chemistry, vol.17(2007), p. 965-971

A similar problem concerns structure investigation of distorted surface sites of crystals.
On the other hand, the lack of precise structure information of nanocrystalline materials is well known.
Hence, surface layers must exist and it is most likely that they have different structures.
Krause: Analysis of the composition and structure of glass and glass ceramics (in: Schott Series on Glass and Glass Ceramics, chapter 3.5, Springer 1999)
Elliot: Structure and chemistry of the apatites and other calcium orthophosphates (Elsevier, Amsterdam 1994)

In this study, defect structures in phase pure HA and Si-HA were observed and characterized for the first time using high-resolution transmission microscopy (HR-TEM).
INTRODUCTION Hydroxyapatite, Ca10(PO4)6(OH)2, resembles the chemistry of bone mineral and has achieved significant application as a bone graft material in a range of medical and dental applications.
Of particular interest was the difference in grain boundary structure observed in HA and 0.8 wt% Si-HA.
Lattice imaging the grain boundaries in 0.4wt%Si-HA (Fig. 5) clearly showed contrast due to two different projections of the apatite structure on either side of the grain boundary.
These results are particularly important since grain boundary structure has been shown to have a predominant influence on the dissolution behaviour of biological apatites [6].

The composites were analyzed using X-ray powder diffraction (XRD) for their crystallographic structure.
From the information of ICDD database, NZF is in crystalline structure while polypropylene is a semicrystalline structure.
Thus, the small peaks or arcs obtained throughout the spectrum may be due to the amorphous structure of PP.
The dielectric constant is due to space charge polarization which arises from the inhomogeneous dielectric structure of the material.
Chougule, Smart Materials and Structure 15 (2006), N36-N39

Initially, after annealing at 950 °C the samples had a hexagonal close-packed structure (α2-phase, type DO19).
The phase composition of deuterides is not changed, although areas of atomic disordered structure appeared.
Electrical, magnetic and halvanomagnetic properties of titanium, hafnium and niobium hydrides // Russian Journal of Inorganic Chemistry. 1972.
Influence of hydrogen on magnetic properties and electron structure of Fe-Ti intermetallic compound // Metallophysics (in Russian). 1988.
Formation of a multiphase disperse structure in hydrogen-bearing titanium upon shear strain under pressure // The Physics of Metals and Metallography. 1999.

The strength of a coralline material is dependent on the pore size and its distribution within the coralline structure.
Smaller the pores higher the strength but some compromise must be attained due to the need of vascularization of the structure.
ESEM images of the cross-section of the hydrocoral reveal a vein-like structure (Figure 2).
This offers a material with a high similarity to the structure of natural bone.
The outer edge of the coral was also found to be more dense and less porous than the inner structure.

Introduction Metallic honeycomb is named by their linear cellular structure.
Some of these applications include transportation, aerospace, environment protect, new power, mechanical chemistry, electronics and construction.
In: Processing and Properties of Lightweight Cellular Metals and Structures, edited by A.Ghosh,T.Sanders,D.Claar , TMS，2002, p.127 [6] J.
Lee, Metal Honeycomb from Oxide paste：Maraging Steel and Super Invar structure and properties, In: Processing and Properties of Lightweight Cellular Metals and Structures, edited by A.Ghosh,T.Sanders,D.Claar, TMS，2002, p.116 [7] Y.
Hurysz, J.Cochran, T.Sanders, Modeling Powder Extrusion Pastes for Forming Light Weight Multifunctional Structures, In: In: Processing and Properties of Lightweight Cellular Metals and Structures ,edited by A.Ghosh,T.Sanders,D.Claar, TMS 2002, p. 167 [10] Mooney M.

When agglomerated nanoparticles are dispersed by adding energy from outside (e.g ultra-sound), they can be damaged – in the case of SWCNTs it is damage of their structure, breaking and loss of expected properties. [1] These structures were identified first in 1991 by a Japanese scientist Sumio Iijima.
Surface-active substances are capable of preventing re-agglomeration of carbon nanotubes after dispersing with ultrasonics. [4] A new phenomenon is nanotubes with surface active substances incorporated in their structures. [5] When a suspension with CNTs is dispersed, it is very important to make sure the energy supplied from outside is not exceeded, because otherwise (depending on the concentration of CNTs) the structure of graphene leafs could be damaged or even broken.
Deformation of the CNTs structure reduces expected positive impact on physico-mechanical properties of the samples with addition of CNTs. [6] 4 Experimental part The experiment is based on previous knowledge and it is focused on the problem of the amount of dispersed suspension.
Comparison of the properties in the diagrams implies that homogenization energy 20 kJ and dispersing in larger volume give the best results, may be due to earlier homogenization entire suspension of carbon nanotubes, superplasticizer and water of magnetic stirrer or damage of structures of CNTs.
SAHUA, An overview on methods for the production of carbon nanotubes, Journal of Industrial and Engineering Chemistry, [online], cit. 1.9. 2014, available at WWW: http://www.sciencedirect.com/science/article/pii/S1226086X13004024 [3] Junrong YU, Nadia GROSSIORD, Cor E.