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The temperature gradient sets the recrystallization speed, determines the quality of the grown structures.
Smith, Measuring and Predicting the Internal Structure of Semiconductor Nanocrystals through Raman Spectroscopy, Journal of the American Chemical Society, 138(34) 10887-10896
Kuryavyi, Thermal stability of multilayer carbon nanotubes produced by the mechanical activation of amorphous carbon. // Coke and Chemistry, 57 (11) (2014) 444-447
Pashchenko, Structure of Ge nanoclusters grown on Si(001) by ion beam crystallization, Inorganic Materials, 49(5) (2013) 435-438
Rubtsov, Bismuth in quaternary and quinary solid solutions based on A3B5 compounds, Russian Journal of Physical Chemistry A. 85(12) (2011) 2062-2067.

The objective of the paper is the study of the vein quartz structure from the contact areas above (Fig. 1).
Bragg factors (Re and GofF) give an assessment of the crystal structure model and are weakly sensitive to background measurement errors and to profile functions.
This fact is most often associated with the imperfection of the crystal-line structure of the test sample, which results from a decrease in crystallization temperature.
Sochalski-Kolbus, Solvothermal synthesis and surface chemistry to control the size and morphology of nanoquartz, Crystal Growth & Design 15 (2015) 5327-5331
Nakahara, Preparation and formation mechanism of silica microcapsules (hollow sphere) by water/oil/water interfacial reaction, Chemistry of Materials 16 (2004) 5420-5426.

The mullite ceramics with an elongated needle-like microstructure and rod like structure can be used as a refractory ceramics, microelectronic packing, microwave dielectrics and infrared-transmitting materials.
This characteristic formation of microstructure and structure may critically determine the low coefficient of thermal expansion (CTE), low density, low thermal conductivity, and dielectric constant as low as 6.7 in mullite ceramic.
The aim of the investigation was to produce a highly developed mullite structure based on the interactions between Al2O3 and silica xerogel converted from sago waste ash.
The heterogeneous structure still appear on all composition of Al2O3 as confirmed by the XRD pattern, which indicate that mullite glass formation was not yet complete.
Pattabhi: E-journal of Chemistry, Vol. 5 (2008), p. 233

Therefore, the realization of insulating heat packaging needs the structure of insulating container with refrigerant which maintains the inside temperature of package constant.
In this case, the length of grafted branch chain gets shorter, which does not favor the formation of spatial network structure of resin.
The close water ions in polymer network structure will generate osmotic pressure in the network structure inside and outside, and water molecules will penetrate into the network structure because of it [7].
Liu: Guangzhou Chemistry Industry, Vol. 37 (2009) No.2, pp.6-8.
Wu: Chemistry and Adhesion, Vol. 28 (2006) No.3, pp.169-171.

Therefore, it is of great importance to realize the preparation of controllable pore structure.
So as to laid the foundations for preparation of P(GMA-co-EGDMA) monolithic columns with controllable pore structure.
As shown, pore size decreased with increasing of proportion of EGDMA, meanwhile, it had a more compact structure.
MC-3 had smaller globules, nevertheless, those small globules formed large clusters which made a more compact structure.
Alharbi, et al, Fast chromatographic determination of caffeine in food using a capillary hexyl methacrylate monolithic column, Food Chemistry, 132(2012) 2217-2223

Optical Sensitivity of Electrospun Fibers containing Quinoxalines derived with Metal ion Chelating Agent Chun Keun Jang, Cheol Jun Song, Wang Yao, Ki Hoon Jang and Jae Yun Jaung1, a 1Department of organic and nano engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul, 133791, Republic of Korea ajjy1004@hanyang.ac.kr Keywords: Quinoxaline, Fluorescence, Electrospinning, Chemosensor Abstract: Fluorescent chromophores are generally known to have planar and rigid p-conjugation systems, and we have been interested in the chemistry of nitrogen-containing heterocyclic molecules for many years.
The porous structure of the electrospun fiber is very suitable for developing high performance sensors when the sensing elements or recognition sites are introduced into electro-spun fiber materials. [7] Quinoxaline compounds which contains electron-donating substituents can be protonated easily at the 1,4-nitrogen positions.
The fluorescence characteristics of the chromophore depend not only on the structure of the aza-crown ether ligand but also on the electronic structure of the metal ion itself.[12] The chelation enhanced fluorescence quenching was also shown from the synthesized aza-crown ether compounds and their electrospun fibers.

Hydrogen sensor: Effect of palladium thickness and porous structure of silicon H.
In the case of Pd/CHx/PS/Si structure, the current recovers rapidly and completely to the initial value which is not the case for the poreless structure.
In the H2 pressure range, the palladium modified PS structure exhibits higher amplitude of (I) responses than that of the Pd/Si (Fig.4) or CHx/PS/Si structures [1, 12].
This leads to the ohmic behavior of the structure.
Kessi, in Proceeding of the 14th International Symposium on Plasma Chemistry, Vol.

However, if the thickness was high e.g. 600 µm the film surface had more wavy structure.
The tablets without coating show clearly the porous structure.
The porous structure disappeared and the surface was smoother after the coating process.
At higher film thicknesses, the films got more wave structure (Fig. 4).
However, if the thickness was high e.g. 600 µm the film surface had more wavy structure.

Ethanol Sensor Based on Hydrothermal Method Prepared Porous α-Fe2O3 Nanorods Yan Wang1, a, Yumei Chen2,b, Jianchao Shi2,c, Jianliang Cao3,d, Guang Sun3,e, Bala Hari3,f and Zhanying Zhang3,g 1Institute of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo, Henan, 454003, China 2Institute of Physical and Chemistry, Henan Polytechnic University, Jiaozuo, Henan, 454003, China 3Institute of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo, Henan, 454003, China ayanwang@hpu.edu.cn, bchenyumei@hpu.edu.cn, cjch621@hpu.edu.cn dcaojianliang@gmail.com, emcsunguang@hpu.edu.cn, fhari@hpu.edu.cn, gzhangzy@hpu.edu.cn Keywords: Gas Sensor, Ethanol, Hydrothermal Synthesis, α-Fe2O3, Nanorods.
The as-prepared α-Fe2O3 has the porous nanorods structured with the length of about 200 nm, diameter of about 50 nm and high surface area (255.2 m2·g-1).
The analysis results of the as-prepared materials presented that the as-prepared α-Fe2O3 have the porous nanorods structured with the length of about 200 nm, diameter of about 50 nm and high surface area (255.2 m2·g-1).
The samples were well organized on the surface and possess a regular pore structure.
The as-prepared porous α-Fe2O3 nanorods have the porous nanorods structured with the length of about 200 nm, diameter of about 50 nm, mesoporous structure and high surface area of 255.2 m2·g-1.

The dissolution of KCa(PO3)3 phase formed a pore structure in KCa(PO3)3-CMP samples.
Introduction Among various types of biomaterials, biodegradable calcium phosphate ceramics has been considered for use in dental and medical areas for the repair and reconstruction of diseased or damaged bones due to the fact that they have a good solubility in biological environments, similar chemistry to bones and diversity in chemical composition [1].
But, the dissolution of KCa(PO3)3-CMP samples were found with the formation of pore structure, (Fig. 3).
The dissolution of KCa(PO3)3 phase formed a pore structure in KCa(PO3)3-CMP samples.
There is a possibility to control the dissolution rate of CMP by adding KPO3 and to form porous CMP structure for the use in bone regeneration.