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Introduction Recently, Organic-inorganic perovskite structured materials based on organolead trihalide compounds have been developed, resulting in very effective absorber in solar cells, with verified efficiencies of up to 22.10%.[1] Moreover, this family of materials suitable for solution fabrication photovoltaic solar cells.
The measured films show the same perovskite structure, fingerprinted by the XRD peaks located at 14.1°, 28.4°, 43.2° and 58.8°.
Those peaks can be assigned to the (110), (220), (330) and (440) facets of CH3NH3PbI3-xClx, respectively.[6, 9, 13] The intensity of the XRD peaks related to the perovskite structure increases together with the annealing temperature, moreover, the larger grain size indicates improved crystallization of the perovskite film, which is consistent with the SEM results.
Fig. 4 Structure and performance of perovskite solar cells, (a) device architecture and (b) energy-level diagram of the devices, (c) current density–voltage (J–V) curves, Insert: the diagram for density–voltage measurements.
Kim: The Journal of Physical Chemistry C, Vol. 118 (2014) No.46, p.26513

Ionic liquid-assisted synthesis of anatase nanostructured TiO2 aerogel doped with Fe3+ by a low temperature sol-gel process and its photocatalytic performance Ningning Wang , Chunling Yu*, Hongyi Dai, Yinghua Fu*, Guolin Shao, Xiaoli Dong School of Chemistry Engineering & Material, Dalian Polytechnic University, Dalian 116034, Liaoning China Keywords: TiO2 aerogel; Fe3+ doping; Ionic liquid; Low temperature; Ambient drying Abstract. anatase crystalline TiO2 aeroge and TiO2 aerogel doped with Fe3+ were prepared at low temperature (60℃) using ionic liquid(IL) assisted sol-gel method.
As an attractive novel environmentally friendly template solvent, IL can reduce the rate of hydrolysis reaction of titaium tetrabutaoxide, which can yield more porous structure and strengthen the skeletal structure of TiO2 aerogel.
Results and Discussion Fig.1 shows the XRD patterns of P25, pure TiO2, and TiO2 aerogel doped with Fe3+(3%).The crystal structure of pure TiO2 and TiO2 aerogel doped with Fe3+ were assigned to the anatase form of TiO2 as a unique phase.
The structure of particles is quite similar although there is a noteworthy difference between agglomerate sizes.

Therefore, pretreatment process needs to be conducted at first, in order to change these complex properties, by breaking the lignin and the crystalline structure of cellulose while simultaneously increasing the porosity of cellulose.
This addition of 1-ethyl-3-methylimidazolium acetate caused the disruption and solubilization of the switchgrass cell walls structures at mild temperature, and completely solubilized the plant cell walls within 3 hours of exposure at 120oC.
It was reported that IL pretreatment changed the structure and provided more accesible surface area for enzymatic delignification.
This is pointed out higher crystallinity degree in the structure of the treated fibers, which is obviously caused by the removal of lignin during the treatment.
Rogers, Complete dissolution and partial delignification of wood in the ionic liquid 1-ethyl-3-methylimidazolium acetate, Green Chemistry. 11 (2009) 646-655

Hydrothermal Synthesis of Yttrium Hydroxide Nanotubes Huijun Rena, Guoqiang Tanb, Lihua Song, Wei Zhang and Ao Xia Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science and Technology, Xi'an 710021, China arenhj@sust.edu.cn, btan3114@163.com Keywords: Hydrothermal synthesis; Yttrium hydroxide Abstract.
In the hydrothermal method, because the rare earth hydroxide has the special hexagonal crystal structure to have the tendency of growing one-dimensional structure.
It has the unique and better specialties of the rare earth element, such as 4fr5dx6l2 electronic shell structure, the high electronic valence, the large radius, the strong polarization, the electron energy level, the variety of electronic spectrum and the active chemical properties.
Ou-Yang, Y(OH)3 and Y2O3 with novel structures: formation and mechanism, Mater.

The flame suppression mechanism by adding layered silicate nanocomposites is based on formation of a carbonic layer and its structure.
Reichsfeld, Chemistry and Technology of Organosilicone Elastomers, Leningrad: Khimiya, 1973
Mikitaev, Polymer nanocomposites: structure, production and properties / Nanostructures in polymers and polymer nanocomposites: I All-Russian Scientific and Technical Conference, 2007
Structure of layered silicates, nanocomposite structure and preparation, Kauchuk i rezina, 5 (2004) 23-29

Experimental The basic sensor structure and fabrication process are illustrated in Fig. 1.
Thin n-type 4H-SiC lateral cantilevers were then epitaxially grown as reported in [4] to form a relatively large table-like structure with atomically flat (i.e., free of SiC bilayer steps) 4H-SiC top surface.
The difficult task of thermally modeling this sensor structure (with complicated under-cantilever growth geometry [4]) was not undertaken, so the operating temperature of the Schottky diode sensor element is known only for room temperature (i.e., with no bias applied to the heater).
Nevertheless, we suggest that significant under-cantilever SiC deposition combined with the high thermal conductivity SiC adversely affects heater power required to achieve higher temperature operation of this sensor structure.
Ceramic Sensors, Electrochemical Soc. (1996), p. 92 [6] CRC Handbook of Chemistry & Physics 42 nd Edition (1960), p. 2593 10-4 10-5 10-6 10-7 10-8 10-9 Air, N2 Air, N2 Air, N2 Air, N2 20 ppm H2 40 ppm H2 (b) 80 ppm H2 140 ppm H2 200 ppm H2 N2 H2Air Air N2 N2 H2 H2 Air Air Air Air IH = 110 mA, VSensor = 0.9 V IH=0 mA, VSensor=1.1V (a) 0 50 100 150 Time (minutes) Time (minutes) Fig. 4.

Yogyakarta, Indonesia 5Department of Chemistry, Universitas Airlangga, Surabaya, Indonesia abrian@tf.itb.ac.id Keywords: Tin oxide, multi-walled carbon nanotube, composite, nano-structure, carbon monoxide gas sensor.
Gas sensor based on nano-structured tin oxide (SnO2) and multi-walled carbon nanotube (MWCNT) composite material has successfully been synthesized.
Basically, metal oxide semiconductor-based gas sensor material (SMO) must have a grain structure on nanometer scale that has a high surface area to volume ratio [8].
The XRD results of SnO2 show the peaks 110, 101, 200, 220, 211, 301 and 321 with diffraction angles at 2θ = 26.7o, 33.97o, 38o, 51.8o, 54.8o, 66.1o which is a cassiterite crystal phase with a tetragonal rutile structure (JCPDS No. 41-1445).

Convection-diffusion processes play an important role in physics, chemistry, and biology [9].
Final Remarks Flow systems are characterized by configuration (structure, design) and by performance.
The best performance relies on an optimal structure.
Bejan, Shape and Structure, from Engineering to Nature, Cambridge University Press, Cambridge, 2000 [3] A.
Miguel, A study of entropy generation in tree-shaped flow structures, International Journal of Heat and Mass Transfer 92 (2016) 349-359 [20] A.

Mohd Suib4, Chen Soo Kien1,3* 1Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia 2Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia 3Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia 4School of Applied Physics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia *Corresponding Author: chensk@upm.edu.my Keywords: YBa2Cu3O7-δ, co-precipitation, superconductivity, XRD, FESEM Abstract.
The phase formation and crystal structure of the samples were characterized by X-ray diffraction (XRD) method at room temperature using a PW 3040/60 MPD X’Pert Pro Panalytical Philips DY 1861 diffractometer with Cu-Kα radiation source.
Analysis of the XRD results revealed that both samples are composed of Y-123 as the dominant phase with orthorhombic crystal structure (ICSD: 01-078-2144).
As shown in Table 2, the a, b, and c lattice parameters were found to be nearly constant for the samples indicating that the number of calcination process did not influence much the crystal structure.
The images show that all the samples exhibit an irregular structure.

Besides the basic characteristics of ordinary carbon fibers, such as low density, high modulus, high strength and conductivity, it also have less defects, high surface area and compact structure characteristics, etc.
Experimental results and analysis The morphology and structure of CNFs were characterized by S-4800 type scanning electron microscope（SEM）and JEM-2010 type transmission electron microscopy（TEM）respectively.
The CNFs were successfully synthesized in the pyrolysis flame and their typical form and structure are as shown in fig. 2 and fig.3.
And this will lead to different CNFs morphology and structure.
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