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Snitka 4 1 Department of Physics, Kaunas University of Technology, Student� 50, LT-3031 Kaunas, Lithuania, 2 Department of Chemistry, University of Helsinki, P.O.
Introduction Lead sulphide has a cubic crystal structure and a narrow direct band gap, small effective mass and high electron mobility.
However, it is important to produce PbS ultra thin films on silicon wafers for integration of optoelectronic thin film structures with electronic devices formed on silicon substrates.
However, the production of the multi-layer structures has complex disadvantages as it is poorly compatible with conventional silicon technology and expensive equipment is needed.
The crystal structure and orientation of the PbS thin films were examined by a Philips MPD 1880 x-ray diffractometer using Cu Kα radiation.

Introduction Cast duplex stainless steels (DSS) are widely used in such industries as chemistry, food, pharmacy, marine and many other fields due their high performance.
In order to disclose the structure, the cast steel was chemically etched with reagent Mi21Fe (30g potassium ferricyanide + 30g potassium hydroxide + 60ml distilled water) that etches δ-ferrite and the σ-phase which is visible as a dark phase in the microscopic image.
Results and discussion Cast steel solution heat treated in water features a two-phase structure with austenite grains distributed in the ferritic matrix.
Processes occurring during solidification and their influence on duplex cast steels structure have been discussed at length in other author’s papers [13-15].
Stachura, Optimisation of structure and operational properties of a duplex cast steel, Duplex 2007 International Conference & Expo, Grado Italy, (2008)

The research of PANI nano fiber or other forms of PANI structure material is considered to be a challenging issue.
Differences of micro-structure and mechanical performance between PLA orientation fiber membrane and PLA fiber membrane without rules was compared which builds the foundation for applying PLA orientation fiber membrane to biomedical materials.
An ideal tissue engineering scaffolds must be able to imitate natural cell matrix both on structure and function.
Collagen nano fiber ,in aspects such as the structure, material and biological properties is closer to the requirements of real tissue engineering materials.
Fu: Journal of inorganic chemistry J, 2061-2064. (2006) [11] M.

Based on the above consideration, in the present study we proposed to synthesize amorphous nickel hydroxide, which has an ideal disordered structure, by the combined chemical precipitation and rapid freezing method.
In particular, the effect of Ce and La codoped on the structure and electrochemical performance has been studied in detail.
The crystal structure of the prepared nickel hydroxides were determined by X-ray diffraction (XRD) analysis using an X'Pert Pro diffractometer and SAED pattern using an JEM-200CX transmission electron microscopy.
The broad and diffuse peak, namely featureless appearance, is typical of amorphous structure.
The formation of this amorphous structure of the samples can be attributed to the rapid freezing which may restrain the growth of nickel hydroxide crystal.

Drofenik1,2,c 1 »Jožef Stefan« Institute, Jamova 39, 1000 Ljubljana, Slovenia 2 Faculty of Chemistry and Chemical Engineering, Smetanova 17, 2000 Maribor, Slovenia a vuk.uskokovic@ijs.si, bdarko.makovec@ijs.si, cmiha.drofenik@ijs.si Keywords: Co-precipitation, Manganite, Microemulsion, Nanosize, Reverse Micelle.
On the other hand, the transformation of chemically similar as-dried composition into an amorphous structure for the microemulsion-assisted synthesized samples, is obvious when XRD patterns a) and b) in Fig. 3 are compared.
More homogenous transition from the precursor compounds into manganite perovskite in the latter case is reflected on the more stable crystal structure formed at 600 oC with only subsequent grain growth noticed with the increase in the annealing temperature.
Crystallization of the secondary phases as well as larger distribution of the particle sizes for the bulk-synthesized sample, might be the reason for the difference in corresponding thermograms, taking into account both difference in the major exothermic peak structure and significantly lower weight loss noticed for the case of the bulk-synthesized sample.
The latter fact is supported by the noticed existence of La2O2CO3 and SrCO3 as transient crystal structures in the process of formation of manganite perovskite when the as-dried powder derived from the synthesis in an ordinary aqueous solution is annealed, whereby the formation of amorphous transient composition, suggesting more homogenous crystallization processes, is noticed within the microemulsion-assisted synthesis.

The structural features of MoTe2 thin film in the XRD plot is fit to the hexagonal structure with lattice parameter values of a=b=3.5190 and c=13.9640 which is in good agreement as reported; a=b=3.52 and c=13.96[9].Stainless Steel substrate are identified at the planes (1 1 1), (2 0 0), and (2 2 0) with standard [10].
The micrographs revealed that the layered structures appeared on both of the films. 1µm 1µm Figure3: SEM Micrograph of MoTe2 thin film deposited at potential of -0.6 V and -1.0 V.
XRD studies confirmed that the present of polycrystalline in nature and possessed hexagonal structure with lattice parameters values a = b = 3.519 nm and c= 13.964 nm.
Spiesser, Semiconducting properties and band structure of MoTe2 single crystals.
Ahuja, Journal of Physics and Chemistry of Solids, 2010. 71: p. 187-193

It concluded that the microstructure is severely refined to UFG structure after the pressing processes; grain size reduces to ~1 μm according to TEM photo.
Interior dislocation structures are demonstrated.
Though little cleavage facets are distributed in the field, the sharpened wall-like structure dominates the surface.
For CP tungsten with as-received CG structure, the DBTT is between 375~ 385 °C, and a reduced range of 300~310 °C is achieved in that of UFG structure produced after multiple ECAP process.
Schubert: Tungsten: properties, chemistry, technology of the element, alloys, and Chemical Compounds (Plenum Press, New York 1979)

In the field of wastewater treatment, CFD is initially employed to research physical processing structures, which only need to consider the physical change, such as predicting the flow pattern and suspended solids distribution in sedimentation tank [1].
There are three common ways of simplification: (1) when the biomass has loose structure and is easily dispersed in water, it can be regarded as a homogeneous liquid phase with sewage; (2) when the biomass has a compact structure, it can be treated as a kind of particulate matter in the solid phase; (3) when gaseous product is less, it can be neglected.
Stabilization pond Stabilization pond is a kind of sewage treatment structures that using natural water purification ability.
Activated sludge treatment Aerobic activated sludge treatment Aeration reactor.Aeration reactor is a structure of aerobic activated sludge sewage treatment, such as push flow aeration tank and cross flow aeration tank.
Mostoufi: Industrial & Engineering Chemistry Research 2013, 52, 9930

Electrocatalytic property for H2O2 reduction of β-Ni(OH)2 Nanosheets Li Jin Feng1,a, Xia Wang1, b, Zhi Ai Yang1,c and Xu Chun Song1,d 1Department of Chemistry, Fujian Normal University, Fuzhou 350007, P.
Introduction Nickel hydroxide has a hexagonal layered structure with two polymorphs, α- and β-Ni(OH)2.
Recently, the syntheses of Ni(OH)2 nanocrystals, including nanoparticles, nantubes and nanoribbons, hollow microspheres, and flowerlike structure, have been reported.
TEM image underlines the homogeneous shape and hexagonal structure of the sample.
HRTEM image of individual β-Ni(OH)2 nanosheets provide further insight into the morphologies and structure details of material.

Subsequently, the structure was annealed at 1550 °C at 20 mbar back chamber pressure and in an Ar atmosphere in a custom-built high-temperature furnace from HTM Reetz, resulting in a bonded sample.
From 550 °C to 850 °C, the material undergoes a transformation into an inorganic structure, eliminating Si-H, Si-CH3, and Si-CH2-Si moieties, accompanied by the release of H2 and CH4.
Suo, et al., "Steady-state cracking in brittle substrates beneath adherent films," International Journal of Solids and Structures, vol. 25, no. 11, pp. 1337-1353, 1989
LEITGEB, et al., "Compound Semiconductor Layered Structure And Process For Preparing The Same," 2022
Laine, et al., "Preceramic polymer routes to silicon carbide," Chemistry of Materials, vol. 5, no. 3, pp. 260-279, 1993