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Introduction In response to increasing demand for safe analytical tools for quantitative and qualitative determination of chemical elements in a wide variety of materials, the field of analytical chemistry has contributed significantly with increasingly more sensitive methodologies that are selective and dependable.
Often these constituents need to be identified quickly or quantified in exploratory analysis in areas such as chemistry, metallurgy, geology, archeology, the arts, materials science, biochemistry, polymer science, forensic science etc.
The spectra of the interfering elements were obtained in the X-ray fluorescence spectrometer - model RIX-3000 of RIGAKU at the X-ray Fluorescence Laboratory of the Chemistry and Environment Centre of IPEN/CNEN-SP.
General Structure Analysis System (GSAS).

The distributions of hardness, phase and structure composition of the surface layers were defined.
It is composed of alternating layers: oxide layer, hardened layer and initial perlite-ferrite structure (Fig. 2).
The formation of nitrogen and carbon and their high-temperature diffusing into the steel structure by anodic PEN/C were described.
Belkin et al., Influence of oxide layer for carbon diffusion by anodic plasma electrolytic carburizing, Protection of metals and physical chemistry of surfaces (in print)
Mukhacheva, Effect of Compositions of Active Electrolytes on Properties of Anodic Carburization, Protection of metals and physical chemistry of surfaces 46 (6) (2010) 715–720

Synthesis and Fluorescence Properties of Pyrazole Oxadiazole Derivatives Dongfeng Li1*, Yun Wang1, Guocheng Yang1, Xinrong Ma1, Shuang Han1, Rongguang Song1, Zhiyuan Xie2 1School of Chemistry and Life Science Changchun University of Technology, Changchun, Jilin Province, China lidongfeng@mail.ccut.edu.cn 2State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry, Changchun, Jilin Province, China xiezy_n@ciac.jl.cn Keywords: Oxadiazole, Pyrazole, Benzothiazole, Fluorescence Abstract: In order to explore high strength organic electrotransporting electroluminescent (EL)materials, twelve new pyrazole oxadiazole compounds containing the benzothiazole or benzene group in the 1 position of pyrazole, the aromatic group in the 3 position of pyrazole and the formacyl group in the 4 position of pyrazole were designed and synthesized.
Their structures were characterized by IR, MS, 1H NMR spectra and elemental analysis.
In recent years, synthesis and study of pyrazole derivatives have become more and hotter in heterocyclic chemistry because pyrazole possesses good biological activity [7-9].
The results show there is slight difference between the two hydrions at styrene structure.
One is the styryl which directly associate with the oxadiazole structure, other is benzothiazolyl group, so the subtle structure of double peak formed.

An appropriate surface chemistry for cell attachment and proliferation is another key issue that should be addressed.
During the pre-incubation in CaCl2 solution, calcium ions were incorporated in the structure.
This result was also observed in case of SEVA-C and SPCL structures (data not shown).
Further studies must be carried out in order to understand the influence of the chemistry and morphology of the surfaces on the formation of an apatite coating.
A biomimetic treatment is not so effective on reaching the bulk of porous structures.

The rehabilitation of structures can be achieved by secondary protection.
Concrete structures are during their use exposed to environmental effects which – owing to their chemical action – are corrosive and are causing degradation of these structures.
One of the necessary steps to ensure adequate service life of structures is their continuous maintenance and in the case of once damaged structures, their rehabilitation.
The chosen environment was determined by the environment to whom the concrete structures are often exposed, primarily to sulfates, chlorides and petroleum products.
Industrial and Engineering Chemistry Research 38. 1999. pp. 3932 – 3941, [3] Chao L.i, Henghu S., Longtu L.: A review: The comparison between alkali-activated slag (Si+Ca) and metakaolin (Si+Al) cements, Cement and Concrete Research Vol. 40, Issue 9, September 2010, p.1341-1349, http://www.sciencedirect.com/, [4] Barbosa V.F.F., MacKenzie, K.J.D., Thaumaturago, C.: Synthesis and characterization of materials based on inorganic polymers of alumina and silica: sodium polysialate polymers.

CD results indicated that PTX caused an increase of unordered structure.
The peptides were synthesized by using standard Fmoc solid-phase chemistry.
Additional PTX leads to a rise in unordered structure content.
Science in China Series B: Chemistry, 2009, 17(8):597-602 [10] Pandita D, Ahuja A and Lather V, et al.
Bioorganic & Medicinal Chemistry, 2006, 14(5):1431-1436

Device structure and fabrication The 1.5 µm strained InGaAsP/InGaAsP MD-MQW structures were grown on an n-InP substrate by low pressure metalorganic chemistry vapor deposition (LP-MOCVD).
Undoped MQW lasers with the same structure were also fabricated for comparison.
So n-type MD-MQW structure can effectively lower Jth, which is the main advantage of utilizing the n-type MD-MQW structure.
The lowest J0 reduced by 23.3% compared with undoped structure.
So the reduction of conduction band offset due to n-type modulation-doping takes more disadvantage in 1.5µm structure than that in 1.3µm structure.

Organic Syntheses and Characteristics of Novel Conjugated Polymers for AMOLEDs Suhee Song1,a, Youngeup Jin2,b, Jooyoung Shim1,c, Kwanghee Lee2,d and Hongsuk Suh1,e,* 1Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 609-735, Korea 2Department of Industrial Chemistry, Pukyong National University, Busan 608-739, Korea 3Department of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea asongsuhee@pusan.ac.kr, byjin@pknu.ac.kr, cjyshim@pusan.ac.kr, dklee@gist.ac.kr, ehssuh@pusan.ac.kr Keywords: conjugated polymer, light emitting diodes (LED), luminescence Abstract.
Once incorporated into the PFs, this three-dimensional structure should prevent the approach of other polymer backbones and, as a result, π-staking of the conjugated polymer backbone could be minimized.15 More resently, we expected that the presence of spiro moieties onto the phenantherene units would enhance the colar stability, with the alkoxy groups in the main chain improving solubility and processability of aromatic conjugated polymers.
In this contribution, we report the synthesis and properties of a new EL polymers utilizing new backbone, Poly((2,6-(3',6'-bis(2-ethylhexyloxy)-spiro(4H-cyclopenta[def]phenanthrene-4,9'-[9H] fluorene)))-alt-(2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[def]phenanthrene))) (spiro-PCPP- alt-PCPP) and Poly((2,6-(3',6'-bis(2-ethylhexyloxy)-spiro(4H-cyclopenta[def]phenanthrene -4,9'-[9H]fluorene)))-alt-(1,4-phenylene)) (spiro-PCPPP) with spiro-structure and cyclopentaphenanthrene backbone.
The structures of the intermediates, monomers, and the resulting polymers were determined with 1H-, 13C-NMR spectroscopy, mass spectrum.
The PL spectra in solid thin films display a vibronic fine structure, which are also more red-shifted over 60 nm than solution conditions.

Although Al atoms can exist stably in CNT, at once they are activated, the electronic structure of CNT is disturbed.
In this work, effective structures of CNT for hydrogen storage are studied by first-principle band calculation.
(b) "Spindle structure" comes out between C and H atoms on the saddle point.
Tachibana: Fundamental Perspectives in Quantum Chemistry: A Tribute to the Memory of Per-Olov Löwdin (Kluwer Academic Publishers, Dordrecht 2002), Vol II, p. 211 [15] A.
Tachibana: Reviews in Modern Quantum Chemistry: A Celebration of the Contributions of Robert Parr (World Scientific, Singapore 2002), Chap. 45, p. 1327 [16] A.

The propagation of the light is orthogonal to the layers of the structure.
Secondly, the electric field's effects on the studied structure's optical properties were examined.
Pugazhendhi, PbS quantum dots-sensitized ZnO nanorods-based third generation solar cells, Materials Today Chemistry 29 (2023) 101444-101456
Kolahdouz, Thin film Cs2TiBr6 perovskite solar cell incorporating functionalized PbS colloidal quantum dots as a hole transporting layer, Journal of Physics and Chemistry of Solids 196 (2025) 112306-031959
Stan, Controlling the interband transitions in a triple quantum ring: Effects of intense laser and electric fields, Journal of Physics and Chemistry of Solids 188 (2024) 111887-111896