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Monodisperse SiO2 nanospheres prepared by batch/semibatch process and its opals Shicheng Zhang1,2,a , Jie Chen 1 , Xingguo Li1,b 1 State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871, China 2 Department of Chemistry, Tsinghua University, Beijing 100084, China a sc-zhang@tsinghua.edu.cn, bxgli@pku.edu.cn Keywords: monodisperse; silica; batch/semibatch; colloid crystal.
Woodcock's results by computer simulations has showed that the stacking of hard spheres in an fcc structure is more stable than in an hcp structure by an amount of Gibbs free energy of 0.005RT per mol, which corresponds to ΔG = 0.13 meV per particle [10].
So the crystal structure of our SiO2 colloidal crystal is inclined to be fcc.

The crystalline structures of the synthesized silver nanoparticles were investigated by X-ray diffractometer.
XRD result showed the characteristic crystalline structure of silver nanoparticles which confirmed the result from Li et al. (2007) [18].
The observed silver nanoparticles were spherical and in uniform structure.
Radiation Physics and Chemistry, 2005, 72, 111–118
The chemistry and properties of nanocrystals of different shapes.

These impurities are capable to affect the HAp crystal structure, crystallinity and solubility, thus limiting the application of HAp, especially in biomedical applications [6].
Previous observation from Hamzah et al [8] determined that HAp which sintered at 300°C has very fine and tiny structure and therefore when integrated with PES membrane, it was able to strongly assemble with the matrix itself and performed the highest permeability coefficient of modified membranes.
Jamshidi, Synthesis methods for nanosized hydroxyapatite with diverse structures, Acta Biomaterialia. 9 (2013) 7591-7621
Kahrizsangi, A comparative study of hydroxyapatite nanostructures produced under different milling conditions and thermal treatment of bovine bone, Journal of Industrial and Engineering Chemistry. 20 (2014) 245–258
Role of hydroxyapatite content, adsorption mechanism and competing anions, Journal of Industrial and Engineering Chemistry. 20:6 (2014) 4014-4021.

Nanoscale zero-valent iron has the microcosmic structure of special crystal shape and lattice arrangement.
Fig. 2 Energy spectrum image Fig. 3 XRD image The grain size and crystal structure of products were analyzed by X-ray diffraction, as shown in Fig.3.
Surface chemistry and electrochemistry of supported zerovalent iron nanoparticles in the remediation of aqueous metal contaminants.
Chemistry of Materials,2001,13,(2):479~486
Structure and magnetism of granular Fe-AI2O3[J].J Magn Mater,2001,226-230:1861-1863

The sampler has a vertical stem onto which a series of sampling bottles are attached forming a tree-like structure.
Due to the tall tree-like structure could be a stability issue in the cave as there are minimum anchorage points and rodents such as bats live inside the caves which could potentially knock the sampler.
A custom auto-sampler was built for drip water chemistry suitable for cave deployments.
Deflection analysis of the rotating arm: First prototype (left) and second prototype with added structures for stiffness (right).
A two-year automated dripwater chemistry study in a remote cave in the tropical south Pacific: Using [Cl−] as a conservative tracer for seasalt contribution of major cations.

The magnetorheological finishing (MRF), which is presented by Kordonski and his cooperators during 1990s [1], is a new machining method for optiacal part which combines electromagnetic, hydrodynamic dynamics and analytical chemistry.
The SiC abrasive is hexahedron structure with sharp edges which can cut the workpiece surface deeply.
The CeO2 particles have the same structure with SiC (see Fig.4(c)), but the surface of the CeO2 particle has been treated by sodium salt which can prevent the abrasives subsiding quickly and keeps the abrasive particles dispersed evenly.
The Al2O3 particles have the same structure with the SiC particles, but the edges are not as sharp as that of SiC particles.
This is due to the fact that the different chemistry characteristics of different abrasive materials.

R China 3 Anhui Key Laboratory of Functional Molecular Solids, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, P.
To obtain YF3 crystals with different shapes and sizes, many wet chemistry approaches have been developed [5-11].
For instance, Wang et al hydrothermally prepared YF3 hollow peanut-like structures via tetrafluroborate complexes as the fluoride source at 160 °C for the desired time [3].
Transmission electron microscope (TEM, H-800) with an accelerating voltage of 200 kV and selected area electron diffraction (SAED) attached on it were employed to characterize the crystal structure.
Small more complex flower-like structures will be form by the diffusion-control growth occurred on the surface (Figure 3c).

Synthesis and Characterization of CdTe/PAA/P-4-VP Quantum Dots Yuhua Jiang 1, Jimei Zhang1, a, Zhao Dai1, Shichao Xu1 , Yong Yin 1, Guo Zheng 1, Bo Sun 2, b 1 Tianjin Key Laboratory of Fiber Modification and Functional Fiber, School of Material Science and Chemical Engineering, Tianjin Polytechnic University, Tianjin, China 2 Department of Material Chemistry, College of Chemistry, Nankai University, Tianjin, China a zhangjimei@tjpu.edu.cn, bsunb@nankai.edu.cn Keywords: CdTe/PAA/P-4-VP quantum dots (QDs), Synthesis, Characterization Abstract.
Therefore, core-shell QDs have been developed, because the shell structure of core-shell QDs can decrease surface defects and passivate nonradiative recombination sites on the surface of core QDs, resulting in enhancement of the fluorescence intention.
The composite nanoparticles were of network structure and the average particle size was about 13.3 nm.
The organic functional groups from PAA and P-4-VP on the surface of CdTe QDs might result in the network structure.

ZHAOb Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, Yunnan University of Nationalities, Kunming 650031, PR China aemail: yanli5901@126.com, email: zhaojishou@163.com b Keywords: Platinum group metals; Pressure cyanidation; dissolution; metal Platinum powder Abstracts: A research study has been undertaken to develop the fundamentals of a method for the direct dissolution of Metal Platinum.
He notes that the heavy platinum group metal complexes have higher thermodynamic and kinetic stability than the light platinum group complexes with the same valence state, same complexing agent and same complex ion geometrical structure.
On the other hand, the lower stability of Pt(CN)42−has a planar square structure, allowing O2 to attack the central ions along the Z axis.
(5) The dissolution mechanism involves the structure and bonding mechanism of cyanide and oxygen adsorbed on platinum atom.
D29 [19] Tan Guo, Andreas Illies, Vince Cammarata, Michael Arndt, William Sonzogni, Journal of Electroanalytical Chemistry 610 (2007) 102–105

Synthesis and Electrochemical Properties of KMn8O16 Nanorods Hao Zheng, Xueya Jiang, Huimin Wu, Meiyu Dan, Chuanqi Feng, Shiquan Wang* School of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China wsqhao@126.com (Shiquan Wang), whm267@gmail.com(Huimin Wu), pfcq@263.net (Chuanqi Feng) Keywords: KMn8O16, Nanorods, Rheological phase synthesis, Cathode material Abstract: KMn8O16 nanorods were prepared by a rheological phase method using KMnO4 and Mn (CH3COO)2·4H2O as reactants.
Their structure is constructed from double chains of edge-sharing [MnO6] octahedra forming large tunnels [5–7].
Single-crystalline KMn8O16 could be suitable for a cathode material for lithium ion batteries because its potassium ions can not only maintain the structure, but also increase the ion diffusion rate [21–25].
The crystallinity and structure of the samples were characterized by X-ray diffraction (XRD), using a Philips X-ray diffractometer with Cu Kα radiation (λ = 1.5405Å).
Parmetier, Progress in Solid State Chemistry, 23(1), 1 (1995)