16 research outputs found

    Structural and Optical Characterization of ZnS Ultrathin Films Prepared by Low-Temperature ALD from Diethylzinc and 1.5-Pentanedithiol after Various Annealing Treatments

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    The structural and optical evolution of the ZnS thin films prepared by atomic layer deposition (ALD) from the diethylzinc (DEZ) and 1,5-pentanedithiol (PDT) as zinc and sulfur precursors was studied. A deposited ZnS layer (of about 60 nm) is amorphous, with a significant S excess. After annealing, the stoichiometry improved for annealing temperatures ≥400 °C and annealing time ≥2 h, and 1:1 stoichiometry was obtained when annealed at 500 °C for 4 h. ZnS crystallized into small crystallites (1–7 nm) with cubic sphalerite structure, which remained stable under the applied annealing conditions. The size of the crystallites (D) tended to decrease with annealing temperature, in agreement with the EDS data (decreased content of both S and Zn with annealing temperature); the D for samples annealed at 600 °C (for the time ≤2 h) was always the smallest. Both reflectivity and ellipsometric spectra showed characteristics typical for quantum confinement (distinct dips/peaks in UV spectral region). It can thus be concluded that the amorphous ZnS layer obtained at a relatively low temperature (150 °C) from organic S precursor transformed into the layers built of small ZnS nanocrystals of cubic structure after annealing at a temperature range of 300–600 °C under Ar atmosphere

    Structural and Optical Characterization of ZnS Ultrathin Films Prepared by Low-Temperature ALD from Diethylzinc and 1.5-Pentanedithiol after Various Annealing Treatments

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    The structural and optical evolution of the ZnS thin films prepared by atomic layer deposition (ALD) from the diethylzinc (DEZ) and 1,5-pentanedithiol (PDT) as zinc and sulfur precursors was studied. A deposited ZnS layer (of about 60 nm) is amorphous, with a significant S excess. After annealing, the stoichiometry improved for annealing temperatures ≥400 °C and annealing time ≥2 h, and 1:1 stoichiometry was obtained when annealed at 500 °C for 4 h. ZnS crystallized into small crystallites (1–7 nm) with cubic sphalerite structure, which remained stable under the applied annealing conditions. The size of the crystallites (D) tended to decrease with annealing temperature, in agreement with the EDS data (decreased content of both S and Zn with annealing temperature); the D for samples annealed at 600 °C (for the time ≤2 h) was always the smallest. Both reflectivity and ellipsometric spectra showed characteristics typical for quantum confinement (distinct dips/peaks in UV spectral region). It can thus be concluded that the amorphous ZnS layer obtained at a relatively low temperature (150 °C) from organic S precursor transformed into the layers built of small ZnS nanocrystals of cubic structure after annealing at a temperature range of 300–600 °C under Ar atmosphere

    Metastases of breast cancer to the thyroid gland in two patients - a case report

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    Introduction: Metastatic cancer is rarely found in the thyroid (only 2-3% of malignant tumours found in that gland); primary sources usually including breast, kidney, and lung tumours. Cases reports: Two cases of advanced breast cancer with thyroid metastases in female patients are presented. The similarities between these two cases included: 1) postmenopausal age; 2) diagnosis based on result of FNAB (numerous groups of cells with epithelial phenotype strongly implying metastatic breast cancer); 3) thyroid function - overt hyperthyroidism in the first woman and subclinical hyperthyroidism in the second one; 4) the presence of nodular goitre in clinical examination, the occurrence of many nodular solid normoechogenic lesions with calcifications in both thyroid lobes in US; and 5) negative antithyroid antibodies. The main difference was the time of establishing diagnosis; in the first woman - before mammectomy, parallel to diagnostics of breast tumour, and in the second woman four years after mammectomy, during cancer dissemination (with right pleural effusion and lung metastasis). In the first case, mammectomy was followed two weeks later by thyroidectomy. The second patient was disqualified from thyroid surgery due to systemic metastatic disease. Conclusions: 1. Fine needle aspiration biopsy of the thyroid gland should obligatorily be performed in patients with breast cancer and nodular goitre, even without any clinical data of metastatic disease. 2. The clinical context of cytological findings is of critical value. 3. In patients with breast cancer accompanied by multinodular goitre, we recommend that more punctures be performed during FNAB than is routinely done. (Pol J Endocrinol 2010; 61 (5): 512-515)Wstęp: Przerzuty do tarczycy są stosunkowo rzadko diagnozowane (2-3% złośliwych nowotworów tarczycy). Najczęściej narządem wyjściowym dla nowotworu przerzutowego są: sutek, nerka i płuco. Opis przypadków: Zaprezentowano przypadki 2 chorych z rozpoznanym rakiem sutka i przerzutami do tarczycy. Podobieństwa pomiędzy pacjentkami obejmują: 1) wiek pomenopauzalny; 2) ustalenie rozpoznania za pomocą BAC (liczne grupy komórek o fenotypie nabłonkowym, prawdopodobnie przerzut z raka sutka); 3) nadczynność tarczycy (jawna klinicznie u jednej pacjentki, subkliniczna u drugiej); 4) obecność wola guzkowego, w badaniu USG liczne lite zmiany ogniskowe normoechogeniczne, lite ze zwapnieniami w obu płatach tarczycy; 5) prawidłowe stężenia przeciwciał przeciwtarczycowych. Główną różnicą był moment postawienia rozpoznania; u pierwszej pacjentki przed mammektomią, równolegle do diagnostyki guza piersi, u drugiej 4 lata po mammektomii, w fazie rozsiewu choroby, z płynem w opłucnej i przerzutami do płuc. U pierwszej pacjentki przeprowadzono mammektomię, a dwa tygodnie później całkowitą tyreoidektomię, wdrożono substytucję L-tyroksyną i przekazano do dalszej terapii onkologicznej. Drugą pacjentkę zdyskwalifikowano z zabiegu z uwagi na stwierdzenie ogólnoustrojowego rozsiewu choroby. Wnioski: 1. Diagnostyka cytologiczna zmian ogniskowych w tarczycy u pacjentek z wywiadem raka sutka powinna być obligatoryjnie wykonywana, mimo braku jednoznacznych cech potwierdzających obecność zmian przerzutowych. 2. Kontekst kliniczny badania cytologicznego ma kluczowy charakter. 3. W przypadku podejrzenia przerzutu do tarczycy należy rozważyć możliwość poszerzenia zakresu badania cytologicznego w wolu wieloguzkowym poprzez selekcję większej liczby bioptowanych zmian ogniskowych. (Endokrynol Pol 2010; 61 (5): 512-515

    Wiara podstawowym dynamizmem moralnym osoby

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    In a morał apprehension the faith has got a personal character. The development of person is a dynamic process. It includes an intelectual heritage wherein it realizes itself as well as constant internal dispositions what comes from the nature of human person. The theological tradition is a retlection on a biblical understanding o f the faith that apprehends it as a reply to the God's vocation. That reply is firstly realized within an observation of the Decalogue, then it has got a heteronomical character, and along the development of personality it nextly enters an internal structure of the human subject, where it receives features of the autonomical morality. It is realized within a transition from the morality of Decalogue to the morality of Beatitudes. The mature faith is an attitude of the entire person and her life, and as such it hecomes a fundamental moral dynamism of the human person

    Fe-Al based composite reinforced with ultra-fine Al2O3 oxides for high temperature applications

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    In this paper, an Fe-Al based composite reinforced with ultra-fine Al2O3 oxides was obtained through sintering of aluminium, iron and mullite ceramic powders using self-propagated high temperature synthesis (SHS). The powder mixture with a 50%wt. content of the ceramic reinforcement was cold pressed and subsequently subjected to the sintering process in vacuum at 1200◦C for 25 minutes under external loading of 25 kN. The complex microstructure of the Fe-Al matrix reinforced with ultra-fine Al2O3 oxides was found to be desired in high temperature applications since only 3% of the relative weight gain was observed after 100 hours of annealing at 900◦C

    Characterization of Low-Symmetry Structures from Phase Equilibrium of Fe-Al System—Microstructures and Mechanical Properties

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    Fe-Al intermetallic alloys with aluminum content over 60 at% are in the area of the phase equilibrium diagram that is considerably less investigated in comparison to the high-symmetry Fe3Al and FeAl phases. Ambiguous crystallographic information and incoherent data referring to the phase equilibrium diagrams placed in a high-aluminum range have caused confusions and misinformation. Nowadays unequivocal material properties description of FeAl2, Fe2Al5 and FeAl3 intermetallic alloys is still incomplete. In this paper, the influence of aluminum content and processing parameters on phase composition is presented. The occurrence of low-symmetry FeAl2, Fe2Al5 and FeAl3 structures determined by chemical composition and phase transformations was defined by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) examinations. These results served to verify diffraction investigations (XRD) and to explain the mechanical properties of cast materials such as: hardness, Young’s modulus and fracture toughness evaluated using the nano-indentation technique

    Structural Stability of Titanium-Based High-Entropy Alloys Assessed Based on Changes in Grain Size and Hardness

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    The thermal stability of the grain structure and mechanical properties of the high-entropy two-phase TiCoCrFeMn alloy produced by powder metallurgy, assessed based on microhardness measurements, was analyzed in this work. For this purpose, material obtained via sintering using the U-FAST method was subjected to long-term heating at a temperature of 1000 °C for up to 1000 h in an argon atmosphere. For homogenization times of 1, 10, 20, 50, 100, and 1000 h, grain size changes in the identified phase components of the matrix were assessed, and microhardness measurements were conducted using the Vickers method. It has been shown that the changes in the analyzed parameters are closely correlated with non-monotonic modifications in the chemical composition. It was found that the tested alloy achieved structural stability after 100 h of annealing. A stable grain size was obtained in the BCC solid solution of approximately 2 µm and the two-phase BCC+C14 mixture of roughly 0.4 µm. Long-term heating for up to 1000 h caused the grain structure to grow to 2.7 µm and 0.7 µm, respectively, with a simultaneous decrease in hardness from 1065 HV to 1000 HV. The chromium and titanium diffusion coefficient values responsible for forming the BCC solid solution and the Laves C14 phase, including the material matrix, were also determined at this level to be DCr = 1.28 × 10−19 (m2·s−1) and DTi = 1.04 × 10−19 (m2·s−1), demonstrating the sluggish diffusion effect typical of high-entropy alloys

    Thermal Diffusivity Characteristics of the IN718 Alloy Tested with the Modified Pulse Method

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    The article presents the use of the modified pulse method (MPM) to determine the temperature characteristics of the thermal diffusivity of alloy 718. The experiment was carried out in the temperature range of 20–900 °C during the double heating of the sample with an interval of two weeks. The results of our own research showed a good correlation in the temperature range of 300–500 °C, during the first heating of the sample, with the recommended changes in thermal diffusivity by NPL & ASM and data from the MPDB database. On the other hand, clear deviations in the results occurred in the range of temperature changes up to about 300 °C, most likely responsible for the electron component of the conductivity of this alloy, and in the range above 700 °C, where there is a clear minimum that may be caused by the δ phase precipitation phenomenon

    Fabrication of Fe-Al Intermetallic Foams via Organic Compounds Assisted Sintering

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    The influence of the addition of organic compounds, such as palmitic acid and cholesteryl myristate, on the porous structure of Fe-Al intermetallics formation has been investigated in detail in this paper. It was found that additives have a significant effect on the final porosity of the obtained sinters. Formed gaseous products from combustion play the role of the foaming agent during Fe-Al intermetallic alloy sintering. The influence of these additives is also clearly noticeable in chemical composition changes of the final products through the increase of carbon content in the porous structure. This is attributed to the thermal decomposition, namely combustion, of the organic additives

    TiCoCrFeMn (BCC + C14) High-Entropy Alloy Multiphase Structure Analysis Based on the Theory of Molecular Orbitals

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    High-entropy alloys (HEA) are a group of modern, perspective materials that have been intensively developed in recent years due to their superior properties and potential applications in many fields. The complexity of their chemical composition and the further interactions of main elements significantly inhibit the prediction of phases that may form during material processing. Thus, at the design stage of HEA fabrication, the molecular orbitals theory was proposed. In this method, the connection of the average strength of covalent bonding between the alloying elements (Bo parameter) and the average energy level of the d-orbital (parameter Md) enables for a preliminary assessment of the phase structure and the type of lattice for individual components in the formed alloy. The designed TiCoCrFeMn alloy was produced by the powder metallurgy method, preceded by mechanical alloying of the initial elementary powders and at the temperature of 1050 °C for 60 s. An ultra-fine-grained structured alloy was homogenized at 1000 °C for 1000 h. The X-ray diffraction and scanning electron microscopy analysis confirmed the correctness of the methodology proposed as the assumed phase structure consisted of the body-centered cubic (BCC) solid solution and the C14 Laves phase was obtained
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