Search results

Hydroxyapatite (HAP, Ca10(PO4)6(OH)2), is an important inorganic material in biology and chemistry.
Its special structure, ionic exchange property, and great adsorption affinity have conferred on this material to attract more attention.
Particularly, ionic substitution plays a critical role in affecting the structure and charge of HAP, which could have an influence on the material in degradation of pollutants.
XRD, FT-IR, SEM, and TEM showed that the substitution of the SiO44− groups for the PO43− groups caused some OH− loss in the HAP structure to maintain the charge balance.

Uematsu Department of Chemistry, Japan Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan Keywords: alumina, pressing, granules, compaction curve Abstract.
The aim of this research is to clarify this dependence of compaction characteristics and sintering behavior on the granules properties by a detailed examination of the internal structure.
Two major types of granules, dense and loose, were fabricated and their properties were correlated with the internal structure of compacts.
These results are meaningful to understand the difference in internal structure observed with the different types of microscope.

Today, it is well know, the green chemistry gives the benefit for environment and has been strongly advocated.
Many previous studies showed that it was indeed feasible to predict the properties or retention time with quantitative structure-retention time relationship (QSRR) models for many organic compounds.
The molecular descriptors of the chemical structure are calculated basis on literatures [4-6].
Gramatica, The influence of molecular lowest-energy conformation on the quality of the subsequent quantitative structure-activity relationship models, J.

Catalytic activity of Ba doped Ta2O5 for methylene blue degradation under visible light Yanhong Zhao1, a*, Min Sun 1,b, Shuwei Wang 1, c, Wenming Tong1, d and Xiaojing Wang1, e College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot, China, 010021 aceyanhong@imu.edu.cn, bqq251365498@sina.com, cwsw0719@163.com dwmtong@foxmail.com, ewang_xiao_jing@hotmail.com * Corresponding author.
The phase structure of samples was characterized by X-ray diffraction (XRD).
In addition, the crystal structure of Ba-Ta2O5 was studied with X-ray diffraction.
XRD and MB degradation measurements The phase structure was identified by X-ray diffraction (D8-ADVANCE, Bruker, Germany) with Cu Kα (λ= 1.5406 Å) radiation at a scan rate of 0.02 2θ S-1.

The nanoscale fracture surface morphology respects the micromechanisms of the failure of the amorphous structure.
The failure is performed in a narrow region via local softening of the amorphous structure in front of the crack tips.
Sereni, Fullerene graphs have exponentially many perfect matchings, J. of Mathematical Chemistry 46 (2009) 443-447.
Bernal, Geometry of the Structure of Monatomic Liquids, Nature (London) 185 (1960) 68-70.

Introduction The C19-diterpenoid alkaloid have attracted considerable interest in phytochemistry and medicinal chemistry because of their complex structures and pharmacological effects [1-3].
In previous investigation, we have reported on a series of structure modifications of the C19-diterpenoid alkaloids [4-9], including some interesting skeletal rearrangements [10-12].
Comparison of the spectral data with 5 led to determine readily the structure of 6.
A comparison to the NMR spectra of 7 with those of 6 showed the absence of an acetoxy group but the presence of an additional conjugated double bond (δH 6.23, 1H, d, J = 4.6 Hz; 5.89, 1H, dd, J =8.4, 7.2 Hz; 5.49, 1H, t, J = 7.2 Hz; δC 124.8 d, 128.8 d, 130.3 d, 137.6 s), leading to establishment of the structure of 7.
References [1] Fengpeng Wang, Xiaotian Liang: The Alkaloids: Chemistry and Pharmacology Vol. 42 (1992), p. 151

Synthesis and Identification of A Hyperbranched Polymer of Tris(8-hydroxyquinoline) Aluminum Linked with Ethylene Glycol Song Bo1, Xiang Junhui1,a , Zhang Fushi2,b , Xing Li1, Liang Xiaohong1 and Chen Shiwei1 1 College of Chemistry and Chemical Engineering, Graduate University of Chinese Academy of Sciences, Beijing 100049, China 2 Department of Chemistry, Tsinghua University, Beijing 100084, China a xiangjh@gucas.ac.cn; b zhangfs@mail.tsinghua.edu.cn Keywords: tris(8-hydroxyquinoline) aluminum, ethylene glycol, energy band-gap Abstract.
Wang et al. reported a hemicage 8-hydroxyquinoline chelates whose structure is facial and stable.
The cage structure leads directly to superior thermal and chemical stability and quantum efficiency enhancement [18].
The alkoxy structure is weakly electron-donating to the five-position of the quinolinolate ligand, which could make the Alq3's quinolines more stable and transport more electrons between two near Alq3 molecules.
These optical results of the polymer indicated that the operation, connecting Alq3 with ethylene glycol to form a three-dimensional cross-linked structure, could increase the energy band-gap but make the photos easier to transfer between the HOMO and LUMO energy levels.

Introduction At the turn of the millennium, Shirakawa, MacDiarmid, and Heeger shared a Nobel prize in chemistry awarded for their effort in the research field of conducting polymers [1-3] which resulted in a great deal of attention to this class of organic semiconductors.
The morphology of the PPPTh films was observed to be a globular structure under most conditions used.
This is suggestive of a decrease in sulfur content from the main structure of the films.
However, the fact that the aromatic C=C stretching around 1427 and 1370 cm-1 are still observed, reassures the existence of the aryl structure.
As mentioned earlier that in the plasma process numerous different fragments could be generated, therefore complex chemical structures of plasma-polymerized polythiophene are possible.

The SEM images show the typical porous structures of activated carbon fabricated from biomass.
The results of the study of surface functional groups in the structure of the best activated carbon materials are shown, many functional groups have been removed from the surface of materials, in which many functional groups have decreased significantly compared to with the original shell sample as C-H group at wavelengths of 2926.93 cm-1 and 2843.52 cm-1 [17, 18]; C-O group at wavelength of 1040.41 cm-1; group C + C at wavelength 1508,54 cm-1 and 1475 cm-1.
The results of research on surface functional groups in the material structure of modified activated carbon materials from activated carbon show that the functional group has changed significantly.
[10] Zang, Y.J., Xing, Z.J., Duan, Z.K., Li, M., and Wang, Y., Effects of steam on the structure and surface chemistry of activated carbon derive from bamboo waste, Applied Surface Science, 2014, 315, 279-286
[35] Jr, M.H., Spiff, A.I., Sorption of lead and zinc on sulfur-Containing chemically, Department of Pure & Industrial Chemistry, 2005, 2(3) 373-385

Optimal Use of Industrial Hemp for PLA Biocomposite and LLDPE Composite Reinforcement Anete Smocaa * and Zane Zelcab Institute of Design Technologies, Faculty of Material Science and Applied Chemistry, Riga Technical University, Latvia aanete.smoca@rtu.lv, bzane.zelca@rtu.lv Keywords: LLDPE; PLA; hemp waste; hemp fibers; reinforced composite; biocomposite.
The linear low density polyethylene are used because its main advantage is the regular structure and high elasticity that can be successfully used to increase the natural fiber content of the composite, thus improving both the composite properties and reducing the polyethylene consumption and material price.
The use of industrial hemp in PLA composite reinforcement helps to improve its biodegradation properties and reduces time, as the fiber helps to absorb water, as well as promotes the microbiological processes required for biodegradation to degrade the biocomposite structure in high temperature and humidity conditions.
Comparison of Tensile modulus of PLA composites reinforced with hemp fibers and LLDPE composite reinforced with hemp fibers or hemp waste At the same time, all three structures are well-bonded to the PLA matrix creating composites with a low deformation (Table 2).
Kukle, The ecploitation properties of hemp fibres containing linear low density polyethylene composites, Material Science and Applied Chemistry. 27 (2013) 17-21