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Introduction Carbon nanotubes (CNTs) were first described by Iijima [1] and since their discovery, they have contributed to the development of studies in the field of physics, chemistry and material sciences.
Many works were completed on the structure, properties [2,3] and potential applications [4,5].
Nanotubes are considered as nearly one-dimensional structures according to their high length to diameter ratio.
Most important structures are single walled nanotubes (SWNTs) and multi walled nanotubes (MWNTs).
The length and diameter of these structures differ a lot from those of SWNT and, of course, their properties are also very different.

Study on synthesis and characterization of unsaturated polyester by enzyme-catalyzed Fenjuan Shao1, Qun Yang2, Lanying Li3, Danian Lu* 1,2,3,* Key Laboratory of Science & Technology of Eco-Textile, Ministry of Education; College of Chemistry, Chemical Engineering & Biotechnology, Donghua University, Shanghai, 201620, China * Correspondening author: dhudanianlu@163.com Key words: enzyme-catalyzed polmerization; fumaric acid; itaconic acid; Qs; self-cross-linking.
The biodegradation of polyesters were carried out with lipase in standard phosphate buffer solutions (pH = 7.4, 37 °C) and the weight remaining of the polyester was used to describe the degree of biodegradation. 3 RESULITS AND DISCUSSION 3.1 The characteistics of the unsaturated polyester The properties of polymer mainly depend on the structure, FA and IA was used to synthesize the unsaturated polyesters and discuss the effect of C=C on the characteristics of the unsaturated polyesters.
Fig. 3 Effect of C=C on Qs (20 min) Fig. 4 Degradation of unsaturated polyesters 3.3 The biodegradation of the unsaturated polyesters The biodegradation of the polyesters depends mainly on its chemical structure and especially on the hydrolysable ester bond in the main chain.
After being cured at 155 ℃ for 20min, the linear macromolecules were changed into netted structures.
Sabaa, Effect of polyester backone structure on the cured products properties, Polym.

Focus have been given on the use of nanostructured-film or porous structured film formed from sintered TiO2 particles as oppose to planar film.
The performance of a PEC cell is dependent on the structure of the top surface, dimensions and crystallinity of the TNT arrays.
From the SEM images, it is observed that ordered nanotubular structure was produced on Ti foil regardless of the applied voltage.
The Journal of Physical Chemistry C,. 111 (2007) 7612-7622
Schwank, A review on TiO2-based nanotubes synthesized via hydrothermal method: formation mechanism, structure modification, and photocatalytic applications.

Table 1 Physical-chemical characteristics UV-VIS characteristics of the samples The samples in ethanolic solvent have similar electronic spectra which those come from structures with an extended conjugation (table 2).
UV-VIS data of the PM1, PM2, PM 3, PM4, PM5, PM5, PM6, PM7 samples in EtOH Domain (nm) PM 1 PM 2 PM 3 PM 4 PM 6 PM 7 Identification 200-230 210 (u) 226 209 228 210 (u) 226 210 (u) 226 228 205 230 π→π* transition 280-290 281 281 281 280 280 281 n→π* transition 315-375 320 (u) - 321 374 318 - 324 - 321 370 319 373 n→π* transition 400- 480 - - - 410 - - - - - - - - 412 437 474 410 437 - conjugated structures Comparing the spectra of the flavonoidic vegetal extracts (PM1, PM2, PM 3, PM4, PM5, PM5, PM6, PM7) with the spectra of the standards (rutine and quercetine), we note the presence of common bands, specific for the flavonoidic structures [10,12].
Spectral investigations (UV-VIS) on the selective extracts emphasized the presence of some phenolic and flavonoidic structures, also confirmed by quantitative determination of the flavonoids, polyphenols and polyphenolcarboxilic acids.
Pogany: Applications of physical methods in organic chemistry, Ed.

A continuous structure had been established crossing the interface between HA and bone-like region at 3 months after implantation.
This study investigated the structure of the bonding zone between HA and host bone, with the aim of elucidating the bonding mechanism.
Table 1 Chemistry of bone, bonding zone and HA (at %, by EDX in TEM) Bone Bonding zone Hydroxyapatite O 37.27 29.01 23.81 P 21.94 23.35 28.43 Ca 40.81 47.41 46.23 Sr 0.23 1.54 It was also found that at 3 months a continuous structure at the atomic level had been built up crossing the interface between HA and bonding zone (Fig. 3), indicating that a chemical bonding had been established.
Continuous structure was observed crossing the interface of HA and bonding zone at 3 months after implantation.

Effect of POSS on the Compatibility and Mechanical Properties of PC/PLA Blends Yi Chen1, a, Yue Peng1, b *, Wenyong Liu1, Guangsheng Zeng1, XiangGang Li1, Wu Wang1 1Hunan University of Technology, Key Laboratory of New Packaging Materials and Technology, Zhuzhou Hunan 412000 2Hunan University, Institute of Polymer Research, College of Chemistry and Chemical Engineering, Changsha 410082, P.R.China ayiyue514@yahoo.com.cn,b*pengyue1230@yahoo.com.cn Keywords: PC/PLA; POSS; compatibility; mechanical properties Abstract.
Depending on the special cube-octameric framework structure and various reactive groups, as a class of new nanosized building blocks, POSS have successfully been incorporated into a variety of polymer systems via blending, copolymerization, and macro-molecular reaction.
The molecular structure and FT-IR spectrum were shown in Fig. 1 and Fig .2.
(a) O-POSS (b) G-POSS Fig. 1 The molecular structure of O-POSS and G-POSS.
This result is attributed to the molecular structure of O-POSS, as shown in Fig. 1, the O-POSS owns stronger hydrophilic groups, which could interact with PLA significantly.

Graphene is promising material for many possible applications due to its unique 2D carbon structure.
The simulation structure was zigzag graphene nanoribbon (ZZ-GNR) with and without NH3 molecules.
The all of simulated structures were optimized for minimum residual forces.
The figure 4 shows the measured resistance change with respect to phase (purging/detection) and concentration of ammonia.Fig. 3: Simulated nanoribbon structure with optimized location NH3 molecule Fig. 4: The NH3 concentration changes (bottom) and corresponding sensor resistance changes during the test period.
Journal of Physical Chemistry C. 2008-09-04, vol. 112, issue 35, s. 13442-13446.

The performance of these composite materials depends largely on the local characteristics of the transition ions, such as the local structure, crystal morphology and distribution.
We can clearly find that the pure PEO matrix and (PEO) 16LiClO4 polymer electrolyte system are dominated by crystal morphology—spherical crystal structure is obvious, the crystal shape rules, and the distribution is compact continuous with clear crystal grain boundary.
Fig. 1 SEM images of the (a) pure PEO and (b) (PEO)16LiClO4 (a) (b) (c) (d) Fig. 2 SEM images of the (PEO)16LiClO4 -x wt.% CeO2 -y wt.% Sm2O3 with (a) x=3，y=3; (b) x=6，y=6; (c)x=10，y=10; (d) x=15，y=15 Appropriate amounts of CeO2 and Sm2O3 can disorder the chain structure and effectively inhibit the crystallization of PEO, which can expand the amorphous region required for the lithium-ion transport.
CeO2 nano-particles break the regular chain structure of PEO molecular, so that the total energy of thermal motion from a large number of chain segments will be reduced.
It has become a cross-point of many disciplines, including materials science, chemistry, physics and other disciplines.

Results and Discussion (1) Morphology of composite polymer electrolyte Previous research indicated that pure PEO and (PEO)16LiClO4 show a typical crystal morphology with spherical shape structure.
Appropriate amounts of SiO2 can disorder the chain structure and effectively inhibit the crystallization of PEO, which can expand the amorphous region required for the lithium-ion transport.
CeO2 nano-particles break the regular chain structure of PEO molecular, so that the total energy of thermal motion from a large number of chain segments will be reduced.
Preparation of new composite electrolytes and ionic conductivity enhancement are inextricably linked, and it is an important direction for future research, although in recent years done a lot of experiments and has achieved some results, but in the course of the study also found a lot of new problems to be solved, some of which also involves materials science, chemistry, physics, energy, science and many other subjects of theoretical knowledge.
However, composite polymer electrolyte ionic conductivity at room temperature needs to be further improved in the composite electrolyte material preparation process, structure and performance there are many issues need to be groundbreaking research.

Introdution Microfluidic devices have been applied in the field of physics, chemistry, nanotechnology, engineering, and biotechnology.
Experiments The ultraviolet (UV) ozone treatment prior to adhering polyimide surfaces was used in this work to prevent liquid leak from the adhered structures [12,13].
Although thermal adhesion is a useful method, it possibly deforms the channels by softening of the polyimide structures.
The EOF micropump structure was photolithographically defined [Fig. 3(b)], and the photoresist was partially removed in a developer (MF319) [Fig. 3(c)].
The depth of the EOF pump structure was adjusted to 25 μm.