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Autothermal gelation synthesis of uniform titania nanoparticles Xixin Wang1,a, Jianling Zhao2,b , Zhaohui Meng3,c,and Jiawei Yan3,d 1School of Material Science and Engineering, Hebei University of Technology, Tianjin 300130, China 2School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China 3College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang 473061, China axixinwang@126.com, bzhaojl@hebut.edu.cn, cmengzhaohui@sohu.com, dyanjiawei@nynu.edu.cn Keywords: titanium dioxide; nanocrystalline; autothermal synthesis.
Titanium dioxide minerals are found in three different crystallographic structures: anatase, rutile and brookite.
As indicated in Table 2, solubility decreased along with the increase of temperature which maybe due to the cross-linked structure between Ti(OH)4.
Results indicate that the as-prepared sample was of amorphous structure with fine anatase crystallines.
The sample after annealling at 400℃ was of anatase structure, while the sample annealled at 650℃ was of rutile structure.

Using proper chemistry, a high strength material can be set in little as a few hours at room temperature.
Increasing the number of pores in a geopolymer can lighten the main body of a structure, and enhance thermal insulation [2], and afford fire protection.
The morphology contains three different structures: fine-grained, plate structure, and white precipitate.
According to one reference [6], plate precipitate is caused by incompletely reacted geopolymer, and the fine-grained structure is attributed to the completely reacted geopolymer.
Fig.4 Microstructure of a geopolymer with plate and white precipitate, fine-grained structure Fig.5 SEM/EDS of (a) geopolymer and (b) the white precipitate Fig.6 shows the microstructure analysis of the foamed geopolymer.

Journal Citation (to be inserted by the publisher ) Copyright by Trans Tech Publications Porous Bioactive Glasses with Controlled Mechanical Strength Linda Fröberg 1, Leena Hupa 1 and Mikko Hupa 1 1 Åbo Akademi University, Process Chemistry Center, Biskopsgatan 8, 20500 Turku, Finland, lfroberg@abo.fi.
The formation of a firm bonding of bone is enhanced when using a porous implant structure [1].
A smaller grain fraction leads to a denser structure than a larger fraction if sintered under the same conditions.
Longer sintering times lead to a denser implant structure for a constant sintering temperature.
However, a closed pore structure starts to form at a porosity level lower than roughly 10 %.

An increasing tendency for the missing-row structures when going from copper to gold will be discussed.
In Fig. 1 (a) the transitions from occupied s state to an unoccupied s state from the same band structure are possible.
Unlike relaxation, the phenomenon of reconstruction involves a change in the periodicity of the surface structure which corresponds to an unreconstructed termination of the bulk structure [19-20].
Pyykkö, Theoretical chemistry of gold, Angew.
Novikov, Electronic structure of materials under pressure, Int.

Figs. 6a-c show the typical columnar grain structure along the deposition direction as a result of heat extraction from the substrate during solidification.
The macrostructure of LENS deposition also shows a distinct band structure perpendicular to the columnar grains, Fig. 6b,c, corresponding to each added layer.
It was observed that the basket weave structure within the LENS layers is coarser at the interface between two bands than inside the bands as a result of reheating of previous layers upon subsequent deposition, Figs. 6b,f.
Fracture occurred in the substrate, which confirmed the integrity of both the LENS deposited structures and the deposition-substrate interface, Fig. 8.
Williams, SpringerLink ebooks – Chemistry and Materials Science, Titanium, Springer Berlin Heidelberg, New York, 2007

Collagen based materials for biomedical applications: preparation and properties Alina Sionkowska Faculty of Chemistry, Nicolaus Copernicus University, Gagarin 7, 87-100 Torun, Poland Email; as@chem.umk.pl Keywords: collagen, biomaterials, films, surface properties, UV-treatment, photodegradation Abstract.
The use of single pulse of UV radiation below ablation threshold did not cause any visible change into the surface structure of collagen film.
The structure of the “micro-foam” is shown in Figure 3.
As one can see in the micro-foam structure the formation of interfacial walls with subsequent rupture leading to ultra-thin fibers with nanometric diameters can be observed.
The “micro-foam” structure can be considered as a matrix for drug delivery.

Imprinted CS Membrane Using EGCG As Template CHEN Sheng1,a, LAN HuaXiu2,b, MA XiuLing2,c 1Fuqing Branch of Fujian Normal University, Fuqing 350300, China 2College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007, China achensheng@fjnu.edu.cn bHuaxiu_lan@126.com cmxl502@163.com Keywords Chitosan, EGCG, Imprinted membrane Abstract A molecularly imprinted membrane was prepared in aqueous media using CS as functional monomer, EGCG as template molecules.
Introduction Epigallocatechin gallate (EGCG, the structure was shown in Fig.1) was regarded as the most important component of the tea, due to its high content in tea and the biologically activity such as free radical scavenging, gene mutation and cancer prevention, apoptotic pathway modulation and anti-inflammatory effects.
Fig.1 Molecular structure of EGCG MIM is the combination of molecularly imprinted technology and membrane technology.
Results and discussion The formation of imprinted membrane The surface of chitosan has a large number of functional groups such as amino and hydroxyl, it is easily combined with the phenolic hydroxyl of EGCG, and linked with the help of sulfuric acid, which showed three dimensional space network structure.
The membrane structure is dense (Fig.3a), when PEG was not added in.

On the other hand, liquid crystal elastomers offer new aspects for chemistry, physics, and material science [1-4].
The helical structure gives chiral liquid crystals some special optical properties, including selective reflection of light, thermochromism, and circular dichroism [5].
Therefore, it is necessary to design and synthesize some novel cholesteric liquid crystal elastomers to study their structure-property relationships and explore their potential applications.
The structure-property relationships and the effect of the content of crosslinking units (CA) on phase behavior and mesomorphism of the elastomers was studied.
Therefore, cholesteric structure of the elastomers was confirmed with POM and XRD.

Fig. 2 Automatic control system framework The main technical parameters The automatic rolling and breaking up tea machine main technical parameters: Dimensions/mm:2200*1210*1900 Inner diameter of the roller /mm:870 Roller line length /mm:1240 Roller motor power /kw:0.75 Roller motor speed /r﹒min-1 :1400 Roller motor working Voltage/v:380 Roller speed /r﹒min-1:60 Pressurized motor power /kw:1.1 Pressurized motor speed /r﹒min-1:1400 Pressurized motor working Voltage /v:380 Working time relay /s·min-1：0～999(Adjustable online) Intermittent time relay /s·min-1：0～999(Adjustable online) The Design evaluation The automatic rolling and breaking up tea machine adopts roller type breaking up, horizontal rolling pressure.And the structure, process , installation, maintenance are relatively simple.
In addition, the tea machine also has the following characteristics: (1)Rolling and breaking up functions were integrated into one tea device, multi-process alternately, high degree of automation , greatly improving the efficiency of tea processing ; (2)The device has the advantages of simple structure, low manufacturing cost.And due to the integration of the tea rolling and breaking up function, significantly reduce the high equipment investment of the tea rolling machine and breaking up machine, the economy is strong; (3)The PLC control technology is applied to the processing of tea making.
However, this design still exists some deficiencies, part of the design structure still yet to be optimized.
It needs further experimental studies to improve its structure.
Beijing[M]: Chemistry Industry Press, 2001

Crystal chemistry of αααα-sialon and related compounds α-sialon has the hexagonal crystal structure with the space group of P31c.
The X-ray diffraction study of α-sialon has shown that the Me cations occupy the large interstitial sites [8]. α-sialon is a nitrogen-rich compound with some oxygen dissolved in the structure.
As seen, the emission of Eu 2+ depends greatly on the crystals structure of host crystals. 200 250 300 350 400 450 500 550 600 650 700 750 0.0 0.2 0.4 0.6 0.8 1.0 Intensity (a.u.)
Wavelength (nm) Fig. 1 Luminescence of rare earth doped Ca-α-sialon 0.5 1.0 1.5 2.0 2.5 3.0 565 570 575 580 585 590 595 Emission peak (nm) m value n = 0, Li-α-sialon n = 0.5m, Li-α-sialon n = 0.5m, Ca-α-sialon λem = 450 nm Fig.2 Tunable emissions of α-sialon phosphors Table 1 Photoluminescence properties of Eu 2+-doped (oxy)nitride phosphors Phosphors Excitation wavelength /nm Emission wavelength /nm Ref β-sialon 303, 405, 450 535 - 545 13 SrSi2O2N2 306, 411, 450 545 18 Ca-α-sialon 300, 400-450 580 -600 7,8 CaAlSiN3 331, 450, 520 635 - 690 10 Ca2Si5N8 450 605 - 616 11 Conclusions α-sialon and related compounds have unique crystal structure consisting of linked SiX4 (X = O, N) tetrahedral networks.
Also, the unique structure promises the down shift of the energy of the 5d electrons of dissolved rare earth ions, hence resulting in a new family of luminescent materials that have the excitability of blue light, high quantum efficiency, small thermal quenching and tunable emission colors.