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Photocatalytic degradation of methylene blue using immobilized nanoparticles of TiO2 supported by SBA-15 surface Youji Li*, Wei Chen, Leiyong Li, Mingyuan Ma College of Chemistry and Chemical Engineering, Jishou University, Jishou 416000, Hunan, PR China *Corresponding author: Tel.: +86–13762157748，Fax:+86-o7438563791.
Moreover, it is interesting to note that the calculated pore size distribution (Fig. 1b) is slightly modified for the TSS, suggesting a porous structure similar to that present in the original support.
By contrast, it can be observed in the TS composites how the titania loading significantly changes the isotherm shape of the support, which is indicative of structure modifications.
In addition, the shift of the pore size distribution maximum to much higher values and the wider pore size distribution (Fig.1b) indicates the breakdown of the structured pore arrangement, which result in drastic decrease of surface areas of TS composites.
It is regarded that the decomposition of MB mainly occurred on TiO2 particles and must be related to the structure of composites.

Synthesis and Electrochemical Performance of Mesoporous Carbon Foams by Microemulsion Method Liang Yang, Mingxian Liu, Lihua Gan*, Yang Li, Xiaoping Wang, Zijie Xu, Longwu Chen Department of Chemistry, Tongji University, Shanghai 200092, P.
The isotherm belongs to IV types cure with the H1 type hysteresis loop, which demonstrates the samples contain mesoporous structure.
The N2 adsorption and desorption isotherms and corresponding pore size distribution curve suggest that as-prepared mesoporous carbon foams have nanoporous structure and possess uniform pore size.
It can be seen that the resultant mesoporous carbon foams show porous network structure.
Semicircle means the pseudo-transfer resistance that is related to the pore structure of carbon electrodes [13].

Furthermore, both high-temperature stable structures are hexagonal.
Then the reaction process and organic structure is analyzed to explore more reasonable composite preparation process.
XD-2 X-ray Diffractor was used to analyze the phase structure and crystal structure of ceramic phases after sintering; MX2600FE Scanning Electron Microscope was used to observe the sample organization and fracture.
Materials Chemistry and Physics, 2009, (113): 626–633
Structure and properties of ultrafine-grained MoSi2+Si3N4 composites synthesized by mechanical alloying.

This is due to the formation of aluminosilicate structure typical to zeolites that can increase the number of negatively charged sites due to replacement of Si4+ ions by Al3+ ions.
The number of cations existing in aluminosilicate structure to balance the negatively charged sites determines the theoretical CEC of that structure, e.g.
Analcime with chemical structure of NaAlSi2O6.H2O has calculated CEC of 454 meq/100 g.
These preliminary results will be used to study further the purification of the solid products to obtain zeolites with higher CECs and more uniform structure for use as advanced materials such as adsorbents or molecular sieves in many industrial purposes especially in water treatment process.
Ismuyanto, “The Effect of Carbon Organic Total and Salinity on The Discharge of Heavy Metals Pb and Cu in Lapindo Mud into the Aloo River”, Journal of Pure and Applied Chemistry Research, Volume 1, 2012, p.41-50

Introduction Since the polymer materials appear, its flammability makes it in the using process having a lot of hidden trouble, it may release a lot of smoke and toxic gases that can cause unpredictable consequences[1].But because of the superior performance of polymer materials, people have to improve the flame resistance from taking the way whatever they could while using a large number of polymer materials, such as adding filler to the material, changing the composition and the structure of materials and adding flame retardant[2].Come to today, adding flame retardant has a better flame retardant effect than other ways, and has been the first choice to improve the flame resistance of polymer materials.
Before that it has been reported that DMMP applied to the Unsaturated Polyester Resin successfully[7] .The reaction mechanism is the formation of C-P bond which is created in the trialkyl phosphate by Michaelis-Arbuzov rearrangement, known as Arbuzov reaction which is one of the most extensively organophosphate chemistry and widely used to prepare phosphonates[8-9].Someone has used this method for synthesis of other phosphorus flame retardant[10].We use a halogen-free and can be used repeatedly catalyst to prepare DMMP in normal pressure, due to a main disadvantage of the normal DMMP preparation is that usually the toxic catalyst contains halogen is used, brought a hazard to the environment, and may be restricted.
It can be seen from Figure 2 that the product has only two kinds of hydrogen atoms, which are the same with the structure of the DMMP completely.
The peak at 3.84ppm is attributed to H3C-O-P in the structure of DMMP; the peak at 1.58ppm is attributed to P-CH3 in the structure of DMMP.
Therefore, considering infrared spectroscopy, we can confirm the structure of the synthesis product is expected, which is the expected dimethyl methyl phosphonate (DMMP).

Graphite fluoride maintains the original layer structure of the graphite.
Thomas had researched the tribological properties of graphite fluoride under the condition of the low temperature, and it was found that the change of friction coefficient has a close relationship with the chemical structure of graphite fluoride [5].
Results and analysis Phase structure of graphite fluoride.
The surface of graphite fluoride is overlapping structure which is composed of chemical bonds, thermal stability is good, and it is not affected by the atmosphere, especially under high temperature, high pressure and high load condition, it can still maintain a good lubrication performance.
Himmel, et al: Journal of Physics and Chemistry of Solids, Vol. 67 (2006), p. 1095

ML methods have recently been performed to predict the 3D structures of NPs from experimental data [4, 5].
Kurban: “Tailoring the structural properties and electronic structure of anatase, brookite and rutile phase TiO2 nanoparticles, DFTB calculations”. 
Dalkılıç: “Density-functional tight-binding approach for the structural analysis and electronic structure of copper hydride metallic nanoparticles”.
Frenkel: “Supervised machine-learning-based determination of three-dimensional structure of metallic nanoparticles”. 
The journal of physical chemistry letters, 8(20), 5091-5098, (2017)

The molecular structures of nitrite reductase had been studied.
Two kinds of NiRs were found according to the different structures of enzyme cofactors.
The sequence analysis and clone to the two species structures were made [6].
Laue crystal structure of Shewanella oneidensis cytochrome c nitrite reductase from a high-yield expression system.
Journal of Biological Inorganic Chemistry.

Structure of 1,1'-[(3,5-didodecyloxycarbonyl-4-phenyl-1,4-dihydropyridine-2,6-diyl)dimethylen]-bispyridinium dibromide (1).
Chemical structures of the 1,4-DHP amphiphiles have been revealed to be strongly influent on their physicochemical and biological activities.
The structure of synthesised compound 1 was established and confirmed by 1H NMR, 13C NMR, MS and elemental analysis data.
Incorporation of PEG-modified lipids into liposomes is well-known and widely used technique to reduce the rate of protein binding on the complex surface, helping to stabilize the structures.
Sobolev, Central European Journal of Chemistry, 9 (2011) 143

Fig. 2 shows that increasing amount of metakaolin causes finer porous structure.
Samples with metakaolin stored in 97% humidity have a lower porosity and a finer porous structure than samples stored in air, which means, that products of pozzolanic reaction (C-S-H phases and ettringite) were created.
This is caused by the presence of superplasticizer, which reduces the quantity of mixing water and causes the dense, less permeable structure.
This development corresponds with the porous structure, described in chapter 3.1.
Karni , E'Yal Karni, Gypsum in construction: origin and properties, Materials and Structures 28(2) (1995) 92-100.