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The pulsed laser ablation technique is also known for roughening and structuring the target surface, leading to film inhomogeneity and the formation of columnar structure on the target surface leading to massive ejection of droplets [4] In pulsed laser ablation, the presence of droplets on the deposited surface and the asymmetry of the film thickness profile still representing the major limitation of the technique, so, a strong effort have been done to decrease the droplets density [4] but it seems that the only way to achieve their complete elimination, is by better understanding of the physical process that leads to their formation.
With the laser action, a roughening of the crater surface occurs and as reported by several authors [3, 5, 6] a cone-like structure becomes visible in the SEM micrograph.
Guldberg: Z.Phys. and Chemistry, Vol. 5 (1890), p.374

There is increasing demand of activated carbon because of its variety uses such as absorber in industry, capsules of activated carbon in medical uses, animal feed additive in livestock production, store hydrogen gas, drinking water filtration, chemical purification in chemistry laboratory, etc.
It is assume that a homogenous reaction occurs throughout the sample which means it does not consider the structure changes of the sample during reaction[3].
The overall reaction is described as follows: (4) (4) The RPM model considers structure change during the reaction.
The overall reaction is described as below: (5) (5) where ψ is the initial pore structure of the char sample (at X = 0) In order to evaluate these models using the experimental results, the three overall equations is linearized to give the following equations: –ln(1-X) = kVM t (6) 3[1-(1-X)1/3] = kGM t (7) (7) (2/Ψ)[(1-Ψln(1-X)1/2-1)] = kRPM t (8) (8) The experimental data obtained from Cheng et. al.[2] are used to calculate the gasification reaction rate constants.

A mixture of anatase–brookite and anatase–brookite–rutile crystals with well-developed crystalline structure possesses higher activities in photocatalytic than sample with only a mixture of anatase–rutile [3].
It is evident that the resultant crystal structure is affected by the sol-gel pH rather than the soaking time as shown in this study.
During condensation, an acid-catalyzed reaction is preferentially directed to the end of the polymeric chains and leads to achieving less branched and more extended structures.
The Physic and Chemistry of Sol–Gel Processing, Academic Press, San Diego, 1990

The surface chemistry and topography affect the cellular response.
The glass particles cover all the surface, also inside the porous structure, reducing its diameter as shown in Fig. 2-B corresponding to a pore zone.
The bioactive glass coating goes inside the porous structure of biomorphic SiC ceramic down to the higher depth.
Typical globular structures associated with the aforementioned bioactive process can be observed in Fig. 4-A, B, which present the biomorphic SiC ceramics sample coated with bioactive glass after immersion for 72 hours at 37 ºC.

During the drying process, the compressive force that was induced by evaporating would compress the latex particles distortion, and result in cross-linking structures in contact latex particles of the solidified tapes, The Fig.6 showed the cross-linking structures in SEM photograph of green tapes.
Feng: Dope Chemistry SPCC (2001), pp.9
Cross-linking structures in SEM photograph of green tapes fracture

Adsorption of heavy metal ions by Chelate-Fiber Prepared by Chemical Surface Modification Xinliang Liu1, a, Lijun Wang1, Yongli Chen2, Nan Chen2 and Shuangfei Wang1, b 1 Institute of Light Industry & Food Engineering, Guangxi University, Nanning 530004, PR China 2 School of Chemistry & Chemical Engineering, Guangxi University, Nanning 530004, PR China a xinliang.liu@163.com, b wangsf@gxu.edu.cn, Keywords: Chelate-fiber, Surface modification, Adsorption, Heavy metal ions, Xanthate, Aminate.
Fig. 1 FT-IR of Fiber: (a) fiber and XAF, (b) XAF before and after adsorption Fig. 2 A proposed structure of XAF Results and discussion FT-IR spectra of XAF.
The fig. 2, a proposed structure of XAF and metal ion interactions, is in coordination with metal ions and amine groups in polymer structure.

However, to the best of our knowledge, few studies have been carried out on the effects of hydrothermal temperature and Sn4+ concentration on particle structure and photocatalytic activity of Sn4+ doped TiO2 nano powder by hydrothermal method.
The crystal structure was identified by X-ray diffraction (XRD) (D8 powder diffractometer, Bruker, Germany).
The TiO2 powders with different crystal structures were synthesized at a temperature range of 140oC to 220oC.
Zhao: Chemistry of Materials 15 (2003), p.2280 [9] J.

We had known that the swelling properties of thermo-sensitive hydrogel can be adjusted in various degree by changing the internal structure of gel[4], changing the hydrophilic / hydrophobic monomer ratio[5],copolymerizing with ionic monomers[6].In this study, PEG2000 and PEG4000 mixtures in different ratio were grafted at PVA with different weight content of PEG/PVA, graft ratio was calculated as follows according to weight gain method: G=(M1/M0)×100% (3) where M0 and M1 are the weights of PVA and copolymers after purified.
It can easily crystallize and has large enthalpy because of its simple structure.PVA is a stable material in range of phase change temperature of PEG.
Basic temperature-sensitive characteristics of PNIPA were based on the structure itself containing both hydrophilicity and hydrophobic groups, discontinuous reversible phase transition can be occurred at a certain temperature.
Acta Polymerica Sinica,1995(3):321-326 [9] Flory PJ.Principles of Polymer Chemistry.New York;Cornell University Press,1953.573-589

The Low-Temperature Thermal Conductivity of Epoxy Resin Composites Enhanced by Graphene and Modified Alumina Hybrid Fillers Yue Xiang1,2,a, Rongjin Huang 1,2,b, Zhengrong Zhou 1,3,c*,Tao Wang1,d, Li Shi1,e, Wentao Sun1,f*, Laifeng Li 1,2,g 1Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Beijing 100190, China 2University of Chinese Academy of Sciences, Beijing, 100190, China 3The 48th Research Institute of CETC, Changsha 410111, China axiangyue1822@163.com, bhuangrongjin@mail.ipc.ac.cn, czhouzhengrong18@mails.ucas.edu.cn, dwangtao@mail.ipc.ac.cn, eshili@mail.ipc.ac.cn, fwentaosun@mail.ipc.ac.cn, glaifengli@mail.ipc.ac.cn Keywords: thermal conductivity; polymer-matrix composites; low temperatures Abstract.
Due to its two-dimensional structure, graphene can form interconnected bridges and penetration networks, which contribute to the transmission of phonons.
This makes it easy for alumina to be deposited on the large surface of the graphene sheet, forming a coating structure with the graphene.
Figure 4g and 4h show the size and structure of nano-alumina and graphene, and the mapping of Figure 4i ~ 4k shows that M-Al2O3 60%/Gr 1%/EP is mainly composed of Al, C, and O.

The different depth of the diffusion profiles studied seems to result from the previous formation of LSQW (Figs. 2a' and 5b) and LaSQW (Figs. 2b', c' and 5a) that are identified in such structures by the cyclotron resonance (CR) angular dependencies [6].
The results obtained exhibit the LSQW into the diffusion profiles prepared at 900°C (Fig. 5 b), while the lateral SQW cross the 800°C structures (Fig. 5a).
Finally, the self-assembled layers of microdefects embedded into the SQW system appear to be a basis of the silicon microcavities (Fig. 9a) that are revealed by the measurements of the reflectance spectra, which exhibit the band structure of a photon crystal (Fig. 9b).
Gerardy: The Physics and Chemistry of SiO2 and Si-SiO2 Interface (Plenum Press, New York, 1988), p. 299