Average Melting Temperature Research Articles

Improving the performance of machine learning model predicting phase and crystal structure of high entropy alloys by the synthetic minority oversampling technique

It is critical to select the suitable integration of elements that has an influence on phase formation when selecting the proper High Entropy Alloys (HEAs) with desired qualities. Machine Learning (ML) models were used to predict the phase and crystal structure of HEAs in this study. Trained on extensive experimental datasets, the set of input characteristics includes Atomic size difference, Mixing Enthalpy, Mixing Entropy, Valence Electron concentration, Electronegativity difference, Ω and Average Melting Temperature. The phase is divided into three categories: Solid solution (S), Dual phase (D), and Intermetallic (Im). Crystal structure classifications include BCC, FCC, and FCC+BCC. For phase and crystal structure prediction, five ML algorithms were used: Decision Tree (DT), K Nearest Neighbour (KNN), Random Forest (RF), Gradient Boosting (GB) and eXtreme Gradient Boosting (XG Boosting), The classification of the HEAs phase has been predicted with great accuracy using an XG Boosting (80 %) and Random Forest exhibits the highest accuracy (94 %) for crystal structure prediction when model is trained on an experimental dataset. Even though the ML model predicts the classes with a better degree of accuracy (>80 %), the F1 value of each class varies more dramatically. This issue has arisen as a result of an imbalance in the dataset's class distribution. To boost performance, this work uses an ML model in conjunction with the Synthetic Minority Oversampling Technique (SMOTE). According to this approach, XG boosting identified the crystal structure with 93 % accuracy and predicted the phase of HEAs with 84 % accuracy. Additionally, it has been noted that each class's F1 score improved and the difference between them was reduced after using the SMOTE technique. It is evident that the SMOTE approach has improved the ML model's ability to differentiate between the various classes.

Prediction of tensile modulus based on parameters of crystalline structure in polyethylene terephthalate with cold crystallization ability

This work aims to adopt a simple modulus prediction method for the crystalline poly(ethylene-terephthalate) (PET), which has strong cold-crystallization ability. Based on a single melting curve generated by calorimetry, crystallinity and average melting temperature can easily be evaluated and consequently, tensile modulus can be predicted. Nonetheless, in the case of polymers with cold crystallization behavior, such as PET, the melting process is affected by cold crystallization, impeding the simple calculation of the aforementioned important parameters. In this paper, the techniques to eradicate cold crystallization during calorimetry are presented. Accordingly, the results of a tensile modulus prediction model are presented and discussed. The crystallization and melting characteristics of PET were measured by differential scanning calorimetry (DSC). The mechanical properties of the specimens were estimated by standardized tensile tests. The specimens, which were used for mechanical tests were fabricated using conventional injection molding. The samples were annealed at different temperatures in order to obtain different crystalline structures. The results clearly indicate that the prediction technique is capable to describe the tensile modulus of PET accurately in the case of very diverse crystalline structures.

An optimisation study of PCM triple glazing for temperate climatic conditions – Dynamic analysis of thermal performance

PCM-windows can play an important role in the protection of buildings against overheating but also as systems for effective storage of solar energy. The presented study indicated the optimal solution for the triple-glazed window where one cavity is fullfilled with phase change material (PCM) in temperate climatic conditions characteristic for Poland. Regarding different thicknesses, positions, and temperatures of phase change material, the a recommended solution was determined using the simulation technique. The computational model was developed, numerically verified, and experimentally validated. The entire meteorological year analyses were done for the climatic conditions of Central Europe, considering windows exposed to facing the South. The optimal solution was determined using two methods - the Weighted Sum method and the Fuzzy Sets method. Both point out a variant with a PCM layer located in the inner cavity and the average melting temperature of PCM equal to 25 °C. However, different criteria and sets of linguistic variables in fuzzy sets determined different optimal PCM thicknesses ranging from 5 to 20 mm.

Aqueous Solid Formation Kinetics in High-Pressure Methane at Trace Water Concentrations.

Natural gas containing trace amounts of water is frequently liquefied at conditions where aqueous solids are thermodynamically stable. However, no data are available to describe the kinetics of aqueous solid formation at these conditions. Here, we present experimental measurements of both solid formation kinetics and solid-fluid equilibrium for trace concentrations of (12 ± 0.7) ppm water in methane using a stirred, high-pressure apparatus and visual microscopy. Along isochoric pathways with cooling rates around 1 K·min-1, micron-scale aqueous solids were observed to form at subcoolings of (0.3-8.6) K, relative to an average equilibrium melting temperature of (253 ± 1.9) K at (8.9 ± 0.08) MPa; these data are consistent with predicted methane hydrate dissociation conditions within the uncertainty of both the experiment and model. The 36 measured formation events were used to construct a cumulative formation probability distribution, which was then fitted with a model from Classical Nucleation Theory, enabling the extraction of kinetic and thermodynamic nucleation parameters. While the resulting nucleation parameter values were comparable to those published for methane hydrate formation in bulk-water systems, the observed growth kinetics were distinctly different with only a small percentage of the water in the system converting into micron-scale solids over the experimental time scale. These results may help explain how cryogenic heat exchangers in liquefied natural gas facilities can operate for long periods without blockages forming despite being at very high subcoolings for aqueous solids.

Investigation of used PCM-integrated into building exterior walls for energy savings and optimization of PCM melting temperatures

In the study, the effects on the building's thermal energy performance of using two different phase change materials (PCMs) integrated into the exterior walls at various thicknesses and melting temperatures have been investigated. Four exterior wall types have been designed by changing the position of PCM integrated into the exterior wall for the purpose to decrease heating and cooling energy demand. For each wall type, three different thicknesses (layers) have been studied and energy savings that PCM provided by decreasing the heating and cooling energy demands have been calculated on a monthly and annual basis. According to the energy simulation analyses, the configuration provided the highest heating energy savings (21.32 %) on an annual basis is the three-layer BioPCM27 integrated exterior wall with a melting temperature of 21 °C. The monthly optimum melting temperatures of PCMs have been determined based on the charge and discharge processes of PCM integrated into the exterior walls by evaluating the results of hourly energy simulation analysis. The annual average optimum melting temperature varies between 18 and 19 °C, depending on the exterior wall and material types. The three-layer (3L) InfiniteRPCM21C configuration (Type 3) has the best thermal energy performance among all exterior wall types, with 24.45 % total energy savings in the cooling season and 14.76 % in the heating season.

Phenotypic and genomic assessment of the potential threat of human spaceflight-relevant Staphylococcus capitis isolates under stress conditions.

Previous studies have reported that spaceflight specific conditions such as microgravity lead to changes in bacterial physiology and resistance behavior including increased expression of virulence factors, enhanced biofilm formation and decreased susceptibility to antibiotics. To assess if spaceflight induced physiological changes can manifest in human-associated bacteria, we compared three spaceflight relevant Staphylococcus capitis isolates (DSM 111179, ISS; DSM 31028, clean room; DSM 113836; artificial gravity bedrest study) with the type strain (DSM 20326T). We tested the three strains regarding growth, colony morphology, metabolism, fatty acid and polar lipid pattern, biofilm formation, susceptibility to antibiotics and survival in different stress conditions such as treatment with hydrogen peroxide, exposure to desiccation, and irradiation with X-rays and UV-C. Moreover, we sequenced, assembled, and analyzed the genomes of all four strains. Potential genetic determinants for phenotypic differences were investigated by comparative genomics. We found that all four strains show similar metabolic patterns and the same susceptibility to antibiotics. All four strains were considered resistant to fosfomycin. Physiological differences were mainly observed compared to the type strain and minor differences among the other three strains. The ISS isolate and the bedrest study isolate exhibit a strong delayed yellow pigmentation, which is absent in the other two strains. Pigments were extracted and analyzed by UV/Vis spectroscopy showing characteristic carotenoid spectra. The ISS isolate showed the highest growth rate as well as weighted average melting temperature (WAMT) of fatty acids (41.8°C) of all strains. The clean room isolate showed strongest biofilm formation and a high tolerance to desiccation. In general, all strains survived desiccation better in absence of oxygen. There were no differences among the strains regarding radiation tolerance. Phenotypic and genomic differences among the strains observed in this study are not inevitably indicating an increased virulence of the spaceflight isolate. However, the increased growth rate, higher WAMT and colony pigmentation of the spaceflight isolate are relevant phenotypes that require further research within the human spaceflight context. We conclude that combining genetic analysis with classical microbiological methods allows the detailed assessment of the potential threat of bacteria in highly regulated and extreme environments such as spaceflight environments.

Support Vector Machine-Based Phase Prediction of Multi-Principal Element Alloys

Designing new materials with desired properties is a complex and time-consuming process. One of the most challenging factors of the design process is the huge search space of possible materials. Machine learning methods such as [Formula: see text]-nearest neighbors, support vector machine (SVM) and artificial neural network (ANN) can contribute to this process by predicting materials properties accurately. Properties of multi-principal element alloys (MPEAs) highly depend on alloys’ phase. Thus, accurate prediction of the alloy’s phase is important to narrow down the search space. In this paper, we propose a solution of employing SVM method with hyperparameters tuning and the use of weighted values for prediction of the alloy’s phase. Using the dataset consisting of the experimental results of 118 MPEAs, our solution achieves a cross-validation accuracy of 90.2%. We confirm the superiority of this score over the performance of ANN statistically. On the other dataset containing 401 MPEAs, our SVM model is comparable to ANN and exhibits 70.6% cross-validation accuracy. We also found that additional variables, including average melting temperature and standard deviation of melting temperature, increase prediction accuracy by 3.34% in the best case.

Phase transition behavior of pure Fe cells for thermocouple calibration

The fixed points adopted in the international temperature scale of 1990 have generally been used to calibrate contact thermometers, such as thermocouples, to get the highest accuracy. The fixed point for Pd is located at the upper limit range of the Pt/Rh noble metal thermocouple calibration. However, the high price of Pd itself restricts its wide use in calibration laboratories. To overcome this difficulty, this study develops an alternative fixed point having a close transition temperature to the Pd freezing temperature of 1554.8 °C. The alternative is pure Fe with a quoted melting temperature of 1538 °C. To make a thermometric cell, an alumina crucible was used to contain the molten liquid and it was found to be robust enough to last for more than 60 cycles of melting and freezing tests without any chemical and mechanical damage. Two cells were fabricated, and their melting and freezing behaviors were studied using type B thermocouples. By considering the advantage and disadvantages of melting and freezing, the melting temperature was selected as a thermometric transition point for the calibration of thermocouples because of its easy operational processes and acceptable uncertainty level. Using a reference thermocouple that had been calibrated versus a standard radiation thermometer, the average melting temperature of the two Fe cells was 1534.0 °C with an uncertainty of 1.2 °C (k = 2). From the studies, an Fe cell made in an alumina crucible can successfully replace the Pd fixed point.

Mathematical modelling for prediction of Young’s modulus in compositionally complex alloys

A generic mathematical model-based bottom-up approach for high throughput materials development of compositionally complex alloys is established in this study. A general bottom-up technique, in contrast to a top-down approach, entails property selection, element screening, structure identification, and fabrication. The application is used to guide the property selection. The alloy design depends on the screening of contributing elements depending on the necessary property. The usage of mathematical models could help with element screening to meet the property requirement. The properties of the resulting compound alloys may be determined by the attributes of compositionally complex alloys. As a result, developing a model that links the needed attribute to the most important aspects of compositionally complex alloys is critical. The Young’s modulus, which is the considered attribute, is predicted using a predictive mathematical modelling approach based on its relationship with the features: valence electron concentration and average melting temperature. Monte Carlo Simulation is also used to discover the optimum feasible composition in order to improve Young’s modulus.

The thermal proteome stability profile of Trypanosoma cruzi in epimastigote and trypomastigote life stages

Trypanosoma cruzi is a flagellate protozoa being the etiological agent of Chagas disease, a neglected tropical disease, which still poses a public health problem worldwide. The intricate molecular changes during T. cruzi-host interaction have been explored using different largescale omics techniques. However, protein stability is largely unknown. Thermal proteome profiling (TPP) methodology has the potential to characterize proteome-wide stability highlighting key proteins during T. cruzi infection and life stage transition from the invertebrate to the mammalian host. In the present work, T. cruzi epimastigotes and trypomastigotes cell lysates were subjected to TPP workflow and analyzed by quantitative large-scale mass spectrometry-based proteomics to fit a melting profile for each protein. A total of 2884 proteins were identified and associated to 1741 melting curves being 1370 in trypomastigotes (TmAVG 53.53 °C) and 1279 in epimastigotes (TmAVG 50.89 °C). A total of 453 proteins were identified with statistically different melting profiles between the two life stages. Proteins associated to pathogenesis and intracellular transport had regulated melting temperatures. Membrane and glycosylated proteins had a higher average Tm in trypomastigotes compared to epimastigotes. This study represents the first large-scale comparison of parasite protein stability between life stages. SignificanceTrypanosoma cruzi, a unicellular flagellate parasite, is the etiological agent of Chagas disease, endemic in South America and affecting more that 7 million people worldwide. There is an intense research to identify novel chemotherapeutic and diagnostic targets of Chagas disease. Proteomic approaches have helped in elucidating the quantitative proteome and PTMs changes of T. cruzi during life cycle transition and upon different biotic and abiotic stimuli. However, a comprehensive knowledge of the protein-protein interaction and protein conformation is still missing. In order to fill this gap, this manuscript elucidates the T. cruzi Y strain proteome-wide thermal stability map in the epimastigote and trypomastigote life stages. Comparison between life stages showed a higher average melting temperature stability for trypomastigotes than epimastigotes indicating a host temperature adaptation. Both presented a selective thermal stability shift for cellular compartments, molecular functions and biological processes based on the T. cruzi life stage. Membrane and glycosylated proteins presented a higher thermal stability in trypomastigotes when compared to the epimastigotes.

Chemical short range order strengthening in BCC complex concentrated alloys

Atomistic methods are used to anneal two body-centered cubic (BCC) chemically complex alloys (CCAs) in order to assess the effect of chemical short-range order on alloy strength. The two alloys, a model quaternary Co16.67Fe36.67Ni16.67Ti30 and ternary Nb33.33Ti33.33Zr33.33, are represented using simple Zhou interatomic potentials. Chemically random cells are annealed at temperatures 65% of the average melting temperature of the individual elements using a Monte Carlo approach, and the critical stress required to move a/2[111] screw dislocations in the initial and annealed cells are estimated using molecular dynamics simulations. It is shown that annealing leads to a softening of the BCC quaternary alloy relative to the random state, especially for deformation at low temperatures. On the other hand, short-range order has minimal effect on solid solution strengthening in the ternary alloy. These results are modeled using an extension of the Suzuki model of substitutional solid solution strengthening developed for BCC chemically complex alloys. Here the model is modified to account for the effects of chemical short-range order. Good agreement is shown between the model results and direct atomistic simulation data. The model presented should be useful in predicting BCC CCAs with adequate high temperature strength, which will accelerate development of high temperature, high strength BCC alloys for aerospace applications.

A thermosensitive material coated resonant stent for drug delivery on demand.

An electromagnetic energy source in the radio-frequency range delivers power to a stent circuit via resonant inductive coupling, allowing a thermally triggered release of gel via Joule heating. A gold-electroplated, medical-grade stainless steel stent, serving as the base of the prototype device, melts a coating made from an emulsion composed mainly of dodecanoic acid. These coated devices produce wirelessly controllable releases of a gel into thermally regulated, stirred water that is near body temperature. The gel is made from salt, water, and gelatine from porcine skin and used to simulate drug release in this study. Thus, this system serves as a proof of concept to show the viability of controlling local drug delivery using this prototype device. Dodecanoic acid, a fatty acid, has a phase transition from solid to liquid near 43[Formula: see text]C and has relatively good biocompatibility. The average melting temperature of two different emulsions was 40.8±0.7[Formula: see text]C, a suitable value for the targeted application. Demonstration of controllable releases used electromagnetic pulses of approximately 180 seconds in duration, illustrating reproducibility of a controllable release phase while remaining relatively inert in the absence of stimuli. Releases were observable through measuring the conductivity of the water, the water temperature, and the stent temperature. This electrothermally active stent device enables wirelessly controlled local delivery with controlled dosage and timing, a concept with a wide range of potential applications. Some relevant examples include inhibiting restenosis or cancer treatment via targeted chemotherapy.

Lignin-Based Polyols with Controlled Microstructure by Cationic Ring Opening Polymerization.

Lignin-based polyols (LBPs) with controlled microstructure were obtained by cationic ring opening polymerization (CROP) of oxiranes in an organosolv lignin (OL) tetrahydrofuran (THF) solution. The control on the microstructure and consequently on the properties of the LBPs such as hydroxyl number, average molecular weight, melting, crystallization and decomposition temperatures, are crucial to determine the performance and application of the derived-products. The influence of key parameters, for example, molar ratio between the oxirane and the hydroxyl groups content in OLO, initial OL concentration in THF, temperature, specific flow rate and oxirane nature has been investigated. LBPs with hydroxyl numbers from 35 to 217 mg KOH/g, apparent average Mw between 5517 and 52,900 g/mol and melting temperatures from −8.4 to 18.4 °C were obtained. The CROP procedure allows obtaining of tailor-made LBPs for specific applications in a very simple way, opening the way to introduce LBPs as a solid alternative to substitute currently used fossil-based polyols.

Morphological changes and ash fusibility of coal, rice straw and their mixture during CO2 gasification

The gasification behavior of single particle of coal, rice straw, and coal-rice straw mixture were investigated by in-situ heating stage microscope, X-ray diffraction, and scanning electron microscopy. The gasification process of coal particle can be divided into three stages consisting of swelling stage, shrinkage stage, and ash fusion stage, while the swelling stage is not observed for the gasification of rice straw particle. The presence of rice straw particle facilitates the shrinkage of coal particle during the co-gasification process due to the migration and catalytic effect of alkaline components which are abundant in biomass. Further, it was found that the average melting temperature of particles is close to the deformation temperature (DT) of ash sample, implying that the DT may reflect the melting properties of particles in a real gasifier. Finally, the ash fusion mechanisms were explored. It was identified that the formation of high-melting points mullite, quartz and anorthite are responsible for the high ash fusion temperatures of coal (with flow temperature over 1500 °C). The addition of 20 wt% rice straw (with flow temperature of 1133 °C) to coal improves the formation of lower-melting points minerals containing alkaline and alkaline-earth elements, and sulphur in the mixture that facilitates the ash fusion process and induces the slag formation. Thus, the flow temperature of the mixture decreases to 1369 °C. The ash fusion behavior of coal follows the “softening-melting” mechanism, while this behavior of rice straw shows a typical “melting-dissolution” mechanism. The ash fusion behavior of coal-rice straw mixture reveals both mechanisms; however, the “melting-dissolution” mechanism seems to be more characteristic for this mixture.

Clonality Test by PCR - PARR in Real Time of Canine Lymphomas

Background: Lymphoma is a neoplasm of hematopoietic origin that affects canines. The proper establishment of prognosis and rapid institution of treatment are essential for a better quality of life, and immunophenotyping is one of the tools used for this purpose. The objective of this study was to perform a clonality test for immunophenotypic characterization of canine lymphomas using the polymerase chain reaction (PCR) for antigen receptor rearrangements (PARR) technique in real-time from samples fixed in formalin and embedded in paraffin.Materials, Methods & Results: The 23 analyzed samples were fixed in formalin and embedded in paraffin canine lymphoma from the Collection Laboratory of Histopathology of the Animal Pathology Area of the Departament of Veterinary Medicine - Federal Rural University of Pernambuco UFRPE. Samples were processed, their DNA was extracted, quantified, diluted, and standardized at a concentration of 50 ng/µL. After extraction, all samples were subjected to conventional PCR for endogenous control (detection of the IgM target region), in which the extracted DNA was amplified in a final volume of 25 µL. The 128 bp amplified product was detected by 1.5% agarose gel electrophoresis. Of the 23 samples analyzed for the detection of the conserved region referring to the endogenous gene, 91.30% (21/23) amplified the conserved region Cµ by conventional PCR, and two samples 8.70% (2/23) were negative. Endogenous control positive samples were subjected to real-time PCR-PARR for detection of IgH Major (LB), IgH Minor (LB), and TCRγ (LT) target regions. All reactions were performed in duplicate to reduce the risk of false-positive or false-negative results due to technical errors. Samples previously confirmed by immunohistochemistry were used as positive controls for T cell and B cell lymphoma, and MilliQ water was used as a negative control. After amplification, the melting curve gradually increased the temperature by 1C/5 s to 95C during continuous fluorescence monitoring. Of the 21 samples analyzed, 100.00% (21/21) demonstrated clonal amplification. Of these, 57.15% (12/21) were positive for phenotype B, and 42.85% (9/21) were positive for phenotype T.Discussion: Due to the importance of researching and confirming samples from files fixed and embedded in paraffin samples in laboratories, PCR-PARR is a good tool for this purpose. In the present study, real-time PCR analysis demonstrated greater sensitivity in the characterization of the immunophenotype of lymphomas from old samples fixed in formalin and embedded in paraffin. The temperature of melting curve analysismay vary depending on the amount of DNA and its quality. In the present study, it was found that the average melting temperature in the samples varied between ± 3C when compared to that in the control sample for LB and LT, 83.5C and 80C, respectively: in the literature, there is a relative difference in this temperature, which may vary up to 4C. Real-time PCR-PARR was satisfactory in the characterization of the immunophenotype of canine lymphomas from formalin-fixed and paraffin-embedded samples; therefore, its use is recommended for both retrospective studies. The use of PCR-PARR associated with histopathological and/or cytopathological examination in cases of canine lymphomas strongly helps pathologists, provide a safe establishment of the immunophenotype, minimize errors, and optimize the diagnosis, thus directly contributing to the establishment of the prognosis.Keywords: immunophenotyping, lymphoproliferative disease, real-time PCR, TCRγ, IgH.

Саlculation of heat transfer processes at canlendering of polyethylene sheets

Introduction. The technological limitations of the calendering process include the condition of leaving the sheet from the calender in the presence of a middle layer of melt, or a sufficient value of the average temperature of the sheet, which determines the flatness of the sheet with subsequent cooling and glazing in a flat state on the roller conveyor. The process of vitrification of the polymer melt has a wide temperature range, which greatly complicates the calculations.Materials and methods. Processing of high density polyethylene (HDPE) on a calender with three rolls is considered. A series of numerical experiments was performed.Results and discussion. Boundary conditions for the mathematical model of sheet cooling and conditions for numerical integration of the equation of nonstationary thermal conductivity taking into account the heat of crystallization are formulated, the equation is presented in finite differences, using a grid with a step along the sheet length.The letter from HDPE in the physical model is conditionally expanded, the following assumptions are made:1. the thickness of the sheet is much smaller than the diameter of the shafts of the calender, so the orthogonal coordinate system is used;2. the transition of the melt from the initial thickness of the workpiece to the final occurs at the same linear velocity (the melt does not slip on the shaft);3. the thermal conductivity of HDPE is much less than the thermal conductivity of the shaft material, so the temperature of the sheet at the point of contact with the shaft is equal to the temperature of the shaft;4. reduction of sheet thickness in the second gap does not occur;5. energy dissipation in the gaps does not affect the temperature fields in the melt;6. heat transfer along the sheet due to thermal conductivity is absent;7. the width of the sheet is much larger than the thickness, so the model of the cooling process is simplified to one-dimensional, without heat transfer across the sheet.For the surface of the sheet, which is cooled by air by free convection, the method of control volume (heat balance method) was used for the boundary layer with a thickness of half a step of the grid along the thickness of the sheet.Numerical experiments were performed for the following conditions: HDPE performance 500 kg / h; initial melt temperature 235°C; diameter of calender shafts 0,25 m; sheet thickness 1.0; 2.0; 3.0; 5.0 mm. Sheet width 1.0 m. The temperature of the first shaft 125°С, shaft temperatures №2 and №3 were selected under the condition of the average melt temperature at the outlet of the calender 125°С, ambient air temperature 20°С, heat transfer coefficient from the sheet and the shaft to air 25 W / (m2K).An example of the results of numerical integration by the Runge – Kutta method (temperature fields and average melt temperature) is shown in the figures.The theoretical analysis of heat exchange processes during calendering of sheets from high density polyethylene melt is carried out, the technological parameters of calendering and their influence on the main quality parameters are analyzed.For the conditions of the numerical experiment, it was found that when calendering sheets with HDPE with a thickness of 1.0 to 2.0 mm will have to choose a high-temperature coolant, which greatly complicates the system of thermal stabilization of the shafts. A 1 mm thick sheet will not have gloss due to the high temperature of the shafts, and the temperature inhomogeneity of the shaft surface due to the high heat flux density can lead to the formation of a central strip on the surface of the sheet without gloss. Calendering of sheets with HDPE with a thickness of 5 mm or more for the conditions of numerical experiment causes difficulties due to the possible "blasting" of the sheet up (behind the hot shaft).Conclusions. It is established that when calendering sheets of smaller thickness, the heat load on the middle shaft increases, and it may be necessary to use high-temperature coolants. The optimal temperature of the calender shafts is in a narrow range, so when designing new equipment, thermal calculation is important.

In-silico amplification of randomly selected male - specific region – Y (MSY) genes as candidate genes for the selection of fertile indigenous bulls for artificial insemination

Molecular markers-based selection is a novel tool for unbundling complexities associated with the selection of animals for breeding improvement programmes because these markers could contribute to full exploitation of animal potential prior to enrollment for improvement programmes. This study examined in-silico polymerase chain reaction amplification of some selected Male Specific region Y (MSY) genes in genome assemblies including Bos_taurus_UMD_3.1.1/bosTau8 and ARS-UCD1.2/bosTau9;BaylorBtau_4.6.1/bosTau7, Bos_taurus_UMD_3.1/bosTau6, and Baylor4.0/bosTau4. The results of the amplification showed that 12 out of the selected 30 genes were expressed at an average primer melting temperature of 61.78 oC; while salt and annealing oligo concentrations were 50 mM and 50 nM per reaction, respectively. Out of expressed genes; 6, 5 and 1 genes were expressed in genome assemblies Bos_taurus_UMD_3.1.1/bosTau8, ARS-UCD1.2/bosTau9, and BaylorBtau_4.6. 1/bosTau7, respectively. The study concluded that the expressed genes are potential markers for selection of fertile bulls and the primers used are suitable for in-vivo annotation of the genes in the prospective bull selection process for breeding programmes.

PHARMACEUTICAL STANDARDIZATION OF “HINGULADRASA SINDOORA” PREPARED BY ELECTRIC MUFFLE FURNACE

Kupipakwa Rasayana bears a unique place in Rasa Shastra treatises because of its mercurial preparation with quicker action and synergistic effects in the body at very low dose. Rasa Sindoora is one of the Kupipakwa Rasayana a most potent medicine of Ayurveda. Acharaya Sadanand Sharma mentioned in his text Rasatarangini that Hinguladrasa Sindoora has equal property, dose, therapeutic indication, Anupan (Adjuvant) and Pathya (Wholesome) etc. same as Rasa Sindoora. Hinguladrasa Sindoora was prepared with same proportion of Shodhita Hingula (Purified Cinnabar) and Shodhita Gandhaka (Purified Sulphur) as per the reference of Rasa Tarangini. Aim-To standardize manufacturing procedure of Hinguladrasa Sindoora. Material and Method- Purified Hingula and Purified Gandhaka both grounds properly and made into the Shlakshana Churna (Smooth Powder). Three batches were prepared to standardize the procedure by using electric muffle furnace (EMF). Results and Conclusion - Average melting temperature of Shlakshana Churna, Average flame appearing temperature and Average corking temperature were 1850C, 4830C and 7030C respectively. Average yield in three consecutive batches was 85 gm and the average time was 15.41 hrs. Three batches of Hinguladrasa Sindoora preparation concluded that for 200 gm of Shlakshana Churna by following intermittent heating pattern that was mild heat (100-2500C) for 4 hrs., Moderate heat (250-4500C) for 4 hrs. and strong heat (450-7500C) for 7-8 hrs.

Melting of Shocked Boron Carbide

The aim of this work is to determine the melting temperature of boron carbide at high shock pressures. To this end, powder boron carbide samples have been compressed by shock waves with an amplitude of 60–80 GPa. Shocked samples have been recovered for the subsequent electron microscopy, X-ray spectroscopy, and X-ray diffraction analyses. The event of sample melting has been identified by the disappearance of boundaries between particles of the recovered initially powder sample. The pressure and temperature of shocked particles of boron carbide powder have been calculated using a hydrocode based on the previously developed equations of state for boron carbide and experimental setup materials. The average melting temperature of the boron carbide has been determined as Tml = 1900(500) K at the pressure Pml = 70(10) GPa.

Melting and freezing behavior of pure Ni cells in alumina crucibles with different internal structures

Two pure Ni cells for thermocouple calibration were fabricated in alumina crucibles with different internal structures to investigate their melting and freezing behaviors. One of the produced crucibles had a smooth surface, and the other was made with internal circular grooves. The melting and freezing processes of each cell were investigated in 10 melting/freezing cycles using a type B thermocouple calibrated with a standard radiation thermometer. The reproducibility of the melting point was better than that of the freezing point by a factor of more than 2, regardless of the internal shape of the crucible. The freezing temperature gradually decreased with the degree of supercooling, and the slope was observed to be about −0.08 °C. It was found that in terms of reproducibility and easiness of realization the melting point was better than the freezing point for use as a fixed temperature point. Therefore, it is proposed to use the melting point as a fixed point for thermocouple calibration. Regarding the difference in internal structure of the crucible, it was observed that a cell with circular grooves was slightly better in terms of reproducibility of melting and freezing points, but it was still unclear whether this was due to the grooves formed inside the cells, and, thus, additional research is needed. The average melting temperature and uncertainty of the Ni cells fabricated in this study was evaluated as (1454.1 ± 0.9) °C.