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Preparation and characterization of LiMn2-xMgxO4 by Low-temperature Flameless Solution Combustion Synthesis Mimi Chen1,2,a, Xianyan Zhou1,2, Xiangzhong Huang1,2, Mei Huang1,2,Changwei Su1,2, Junming Guo1,2,b, Yingjie Zhang1,2,c 1 The Engineering Laboratory of Polylactic Acid-Based Functional Materials of Yunnan, School of Chemistry and Biotechnology, Yunnan University of Nationalities, Kunming 650500, China 2 Key Laboratory of chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, Yunnan University of Nationalities, Kunming 650500, China a cmm6521@163.com, bguojunming@tsinghua.org.cn(corresponding author), cyingjie@kmust.edu.cn (corresponding author) Keywords: Preperation; Characterization; Mg-doped; LiMn2-xMgxO4; Flameless solution combustion Abstract: The spinel Mg-doped LiMn2-xMgxO4（0≤x≤0.10）lithium ion cathode material was prepared by LiNO3, Mn(Ac)2.4H2O and Mg(Ac)2.4H2O by a low-temperature flameless solution combustion at 400℃
The possible reasons responsible for the quick fading of capacity are generally believed to originate from three aspects[11,12]: firstly, decomposition of organic solvent at higher potentials; secondly, gradually dissolution of Mn3+ to electrolyte via disproportionation reaction; thirdly, Jahn-Teller distortion of the cubic spinel structure of LiMn2O4 during discharging with increase in Mn3+ in the structure.
Mg-doped LiMn2-xMgxO4 materials was prepared by solution combustion synthesis method[9,10], while the low-temperature flameless solution combustion synthesis was adopted to prepare Mg-doped LiMn2-xMgxO4 materials on the base of solution combustion synthesis method in this paper, and the structure of prepared materials was characterized.
The experimental results showed that main phase or pure phase spinel LiMn2O4 (JCPDS, NO.35-0782) was obtained by this method, and crystallinity of Mg-doped LiMn2-xMgxO4 was better than pure LiMn2O4, so a few Mg-doped did not change basic structure of spinel LiMn2O4.
Xia, M.Yoshio, Investigation of lithium ion insertion into spinel structure Li-Mn-O compounds, Journal of the Electrochemical Society, 144 (1996) 825-833

Effect of Different Aromatic Carboxylic Acid Ligands on the Catalytic Activities of Metal-organic Frameworks Liping Wang1, a, Gongying Wang2,b, Fan Wang1,c, Pinhua Wang1, d 1College of Chemistry and Chemical Engineering, Qujing Normal University, P.R.
China 2Chendu Institute of Organic Chemistry, Chinese Academy of Science, P.R.
Moreover, the frameworks of MOF-C and MOF-D have the better symmetric properties and stronger stabilities than those of MOF-B and MOF-C because the symmetric properties of H2BDC and H3BTC molecular structures are better than those of 1,2- H2BDC and 1,3- H2BDC molecular structures.
Consequently, the catalytic activity of MOF may be greatly influenced by its pore size, surface area and unique molecular structure.
The high catalytic activity of MOF based on Zn2+ with H2BDC may be attributed to its high surface area, high porosity and unique molecular structure.

., Amagasaki, Hyogo 660-0083, Japan 3Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University, Osaka 564-8680, Japan a*kenzo@hatta.co.jp, btokuyama@hatta.co.jp, caoki@hatta.co.jp, djunichifukui@icloud.com, eatsushi@mikitec.co.jp, fakionisi@kansai-u.ac.jp Keywords: Austenitic Stainless Steel, Active Screen Plasma Nitriding, Expanded Austenite, Small Thin Rolled Plate.
Results and Discussions Phase Structure and Nitrided Layer Thickness.
Figure 5 shows the layer thickness of S phase determined from the cross-sectional structure photograph in Fig. 3.
Takase, Structure of the Ion-nitrided layer of 18-8 stainless steel, Technol.
Bell, Structure and corrosion resistance of plasma nitrided stainless steel, Surf.

From the images it shows that nano-TiO2 is of spheric granules structure, the diameter of particles is between 50nm and 100nm, and the size distribution is uniform.
Nano-ZnO is of short rod structure, the radial dimension is less than 100nm and the length-diameter ratio is about 3:1, the particle size distribution is uniform.
Chemistry, 2006, 8, 591-595 [3] CHEN Peng-yu, ZHANG Xu, WU Feng, DENG Nan-sheng.
Structure and Photocatalytic Activity of Nanosized TiO2/SiO2 Particles Prepared by Microemulsion.
Chinese Journal of Inorganic Chemistry, 2007, 6, 1045-1050 [7] Xiao Hanning, Li Yuping.

Structure and morphology.
It indicated that as-prepared samples have single-phase crystal structure of Sr2Si5N8 and no apparent impurity phases were found.
Furthermore, rigid host structure based on vertex- linked SiN4 played the role for lowering thermal quenching effect.
Hintzen, Journal of Solid State Chemistry 181 (2008) 515–524
Seilmeier, Journal of Physics and Chemistry of Solids 61 (2000) 2001-2006

In 2007, Zhang[10], another researcher of Changchun Institute of Applied Chemistry, invented the centrifugal spinning on the preparation of non-woven polymer device, the patent proposes the non-woven fabric was prepared by centrifugal spinning, specific device shown in Fig. 2.
The device can prepare the tendon sheath at silk-micron level structure from melt by the first use of centrifugal force, and then the wire was heat- treated to form the carbon nanotubes of nanometers (diameter 20-50nm, length 200-500nm).
Through the rotating cone designed on rotation structure of the apparatus, the melt becomes thin and uniform under the action of centrifugal force, finally nanoscale fibers are formed.
Polymer structure and antimicrobial activity of polyvinylpyrrolidone-based iodine nanofibers prepared with high- speed rotary spinning technique, International Journal of Pharmaceutics. 458 (2013)99-103
[26] Y.R.Yan, Z.M.Qiu, L.Chen, The twenty-eighth annual meeting of the seventeenth session the set [C] China chemistry, 2012

The main element of the natural ECM structure is collagen type I and type III [29].
Structure and Properties of High-Performance Fibers, Elsevier, UK, 2017, pp. 267-300
Bowlin, Electrospinning of nanofiber fibrinogen structures, Nano Lett., 3 (2003) 213-216
Squire, (Eds.), Advances in protein chemistry, 70, Elsevier, 2005, pp. 247-299
Tripathi, Chitin and chitosan: Chemistry, properties and applications, J.

Synthesis and Characterization of the Gold-SiO2 Core-Shell Nanoparticle on the X-Nanozeoliate used for Immobilization of the Alkaline Protease Enzyme Nazanin Farhadyar1, a, Mirabdollah SeyedSadjadi 2, b 1Department of Chemistry,Varamin –pishva Branch , Islamic Azad University,varamin, Iran 2Department of Chemistry, Science and Research Branch, Islamic Azad university, Tehran,14778 Iran anfarhadyar@gmail.com, bm.s.sadjad@gmail.com Keywords: Immobilization; Biocatalytic activity; gold-SiO2 Core-shell, X-type nanozeoliate Abstract.
In this work, we prepared gold nanoparticle core-shell structure by assembling of the gold nano particles on the surface of amine-functionalized x-type zeolite and then used them for immobilization of the alkaline protease.
Enzyme immobilization represents the attachment or incorporation of enzyme molecules onto or into large structures, via simple adsorption, covalent attachment, or encapsulation [10-19].

The crystal structure of the powders was cubic phase barium titanate confirmed by Powder X-ray diffraction (XRD) with CuKα.
The chemical structure of dried gel corresponds to polymer chains of Ti oxyacetate [7]: BaTi acetate gels consist of linked clusters of polymer Ti oxyacetate with surface absorbed Ba ions.
Based on double electrical layers theory of colloid chemistry, colloid stability could be determined by zeta potential.
The XRD patterns of the sintered film showed that BaTiO3 particles were crystallized to a tetragonal structure.
Hsu: Materials Chemistry and Physics Vol.79 (2003), pp.226.

Results and Discussions The grafting of functional group onto any polymeric chain necessarily changes its chemical structure.
Control LDPE film has (CH2)n structure, therefore, the presence of hydrocarbon bonds were dominantly observed.
Fig.2: XPS survey scan of (a) LDPE and (b) LDPE-g-BSO Conclusion The analyses of FTIR spectra revealed the presence of new peak at 1746cm-1 in LDPE-g-BSO spectra, which correlated to the carbonyl (C=O) structure of BSO.
[6] Suri, K., et al., Impact of infrared and dry air roasting on the oxidative stability, fatty acid composition, Maillard reaction products and other chemical properties of black cumin (Nigella sativa L.) seed oil, Food Chemistry, 295 (2019) 537-547
Faria, and A.A.A. de Queiroz, Polyglycerol dendrimers immobilized on radiation grafted poly-HEMA hydrogels: Surface chemistry characterization and cell adhesion, Radiation Physics and Chemistry, 98 (2014) 118-123.