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The phase composition, microscopic structure of the products were characterized by powder X-ray diffraction, scanning electron microscopeandtransmission electron microscope.
Fig. 6 present the SEM images of the product prepared at 1300 oC with differentmolten salts medium.Without the addition of molten salt, large numbers of typical lamellar structure particles which is according with the crystal habit of Ti3SiC2 can be seen in Fig. 6(a).
On the edge of Ti3SiC2crystal grown in alkali chloride molten salt medium, legible growth step and typical layer structure are observed, which can be seen more clearly in Fig. 7.
Taken with the SAED and HRTEM data, this confirms that the flake-like Ti3(Si,Al)C2 crystal has a single crystal structure.
Journal of Physics & Chemistry of Solids. 1999;60:429-39

Microwave-assisted Synthesis and Photocatalytic Activity of Thiourea-modified ZnO Nanoparticles Hai-feng ZHANG1, a, Shi-xiang LU1, b, Wen-guo XU1, c and Feng-xin GAO1, d 1School of chemistry, Beijing Institute of Technology, Beijing 100081, PR China ahfzhang318@126.com, bshixianglu@bit.edu.cn, cxuwg60@bit.edu.cn, dgfx689@bit.edu.cn Keywords: thiourea-modified, ZnO, microwave-assisted, photocatalysts.
ZnO nanoparticles presented typical wurtzite structure.
The crystalline structure was investigated by X-ray diffraction (XRD) on x’Pert Pro MPD X-ray diffractometer with Ni-filtered Cu Ka radiation.
The pure ZnO displayed the typical wurtzite structure according to the standardized JCPDS card.
The XRD spectra of all the thiourea-modified ZnO nanoparticles were similar to the pure ZnO and no new peaks were formed, which indicated the crystal structures didn’t have changed obviously.

Evaluation of concrete permeability by monitoring alkali saturated conductivity of concrete incorporating mineral admixtures Quan-Lin Niu 1,a ,Nai-Qian Feng 2,b 1 Shandong university of technology, Zibo, Shandong 255049, P.R .China 2 Department of civil engineering, tsinghua university, Beijing, 100084 P.R.China a mail: niuquqanlin@tsinghua.org.cn, b mail: fengnq@tsinghua.edu.cn Keywords: conductivity; pore solution; Mineral admixture Abstract: Concrete conductivity is the reflection of the micro pore structure and the pore solution conductivity of concrete, but the conductivity of pore solution changes considerably as different mineral admixtures are added, though the change is not always relevant to permeability and Cl - diffusivity.
Table 3 Mix proportion of concrete specimens W/B cement admixtures sand gravel water AK 0.30 500 / 760 1020 150 AFA (30%fly ash) 350 150 760 1020 150 ASL (40%slag) 300 200 760 1020 150 ANZ (20%zeolite) 400 100 760 1020 150 AMK (20%metakaolin) 400 100 760 1020 150 ASF (10%silica) 450 50 760 1020 150 BK 0.4 420 / 800 1080 168 BFA (30%fly ash) 294 126 800 1080 168 BSL (40%slag) 252 168 800 1080 168 BNZ (30%zeolite) 294 126 800 1080 168 BMK (20%metakaolin) 336 84 800 1080 168 BSF (10%silica fume) 378 42 800 1080 168 In the mean time, mineral bearing pastes were prepared for mercury intrusion to illustrate the effect of mineral powder on the micro pore structure of the pastes.
Fig.2 alkali saturated conductivity of concrete incorporating different mineral admixtures Fig.1 charge passed of concrete incorporating different mineral admixtures The concrete specimens incorporating natural zeolite owned high charge passed and high alkali saturated conductivity, this is partly due to the high porosity of natural zeolite structure, but its pore diameter is usually less than 10 Å[11] and usually impossible for actual chloride diffusion.
It is well known that the diffusion of ions takes place in and through capillary pores, and the pore structure such as porosity and tortuousity of pastes are primary factors influencing the ion diffusion ability.
Chinese journal of inorganic chemistry, 2001,16(1): 31-36.

Among them, the hydrothermal method has specific advantage in producing uniform crystal phase powder compared with traditional solid-phase reaction and the wet chemistry method including mild reaction conditions, inexpensive precursors, or equipments [12,13].
The morphology and structure of the samples were characterized by SEM, XRD, TEM and HRTEM.
The phase structure of the final products was characterized using X-ray diffraction (XRD, BRUKER-AXS, Germany).
Fig. 1 clearly shows that the phase structure of the initial product.
However, the heat treatment at 300 oC does not result in the formation of the perovskite-structured NaNbO3, because the XRD pattern of the resulting substance showes the typical pattern of a non-crystalline structure.

Introduction Titanium alloys are widely used in various industries (aircraft building, rocket production, shipbuilding, medicine, chemistry and many others) due to a good combination of high specific strength and excellent corrosion resistance.
However the UFG structure formation, especially in bulk specimens, is still a grave scientific and engineering problem.
Lojkowski, Effect of hydrostatic extrusion at 600–700°C on the structure and properties of Ti–6Al–4V alloy.
Froes, Formation of a submicrocrystalline structure in TiAl and Ti3Al intermetallics by hot working, Mater.
Salishchev, Submicrocrystalline structure formation in Ti and Ti-64 alloy by warm “abc” deformation, Mater.

Lysenko1 1Lashkaryov Institute of Semiconductor Physics NAS of Ukraine, Kyiv, Ukraine 2 Department of Common and Inorganic Chemistry, National Technical University of Ukraine “KPI”, Kyiv, Ukraine a nazarov@lab15.kiev.ua Keywords: cold emitter; carbon-rich a-SiC; conductance AFM.
Surface morphology and bulk structure of the a-SiC layers.
Local forward I-V characteristic of the a-SiC/p-Si structure (KO155)..
The comparison of the electron emission current with the average current flowing through the structures allows us to extract the efficiency of the electron emission in our structures.
Koshka, Structure, paramagnetic defects and light-emission of carbon-rich a-SiC:H films, J.

To understand the mechanism of photodegradation, detailed information on the morphology of the nanostructured ZnO surface and the surface chemistry was obtained by scanning electron microscopy (SEM), secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS).
These porous structures allow better diffusion of reactants and products, thereby improving mass transport.
All films show granular structures.
Exploring porous structures plays a vital role in photocatalysis because of their distinctive microstructural benefits.
Zhou, Enhanced photocatalytic activity of ZnO thin films deriving from a porous structure, Materials Letters,150 (2015) 1-4.

Aluminum is a trivalent atom that needs cationic balancing ions on the structure, that can lead polar molecules, such as H2O, easily bonded on the structure.
Ethylene glycols act as a plasticizer to the membrane structure.
The addition of EG into the membrane structure will provide a more flexible structure of the membrane.
However, excess of EG will lead to steric structure due, as more excess EG present in the membrane structure, it will fill in the free volume between polymer chain and will hinder gas to pass through easily [15].
Hence, the effect of continuous gas permeations leads the membrane structure to be swollen.

This, in turn, catalyzes the reaction and facilitates the breakdown of the macromolecular lignin structure into fragments of lower molecular weight.
Cambridge: Royal Society of Chemistry; 2012. doi:10.1039/9781849735063
Physicochemical characterization of ethanol organosolv lignin ( EOL ) from Eucalyptus globulus : Effect of extraction conditions on the molecular structure n.
Extraction and Modification of Sugarcane Wax View project Historical-Cultural Psychology and Historical-Critical Pedagoy as theoretical frameworks for Chemistry teaching View project. n.d
Chemistry and Delignification Kinetics of Canadian Industrial Hemp.

The results indicating the face-centered cubic structures and crystalline nature of AuNPs and AgNPs.
The XRD pattern test results have shown a pattern of the diffraction from the Au NP with an fcc structure of the crystalline.
XRD pattern vertices have been centred surrounding the face in the gold because of cubic structure (fcc).
Journal of Materials Chemistry B. 4(2016): p. 793-800
Toxicological & Environmental Chemistry, 2018. 100(5-7): p. 629-643