Academic literature on the topic 'Datura metel PMT'

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Journal articles on the topic "Datura metel PMT"

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Velázquez-Márquez, Sabina, Iván M. De-la-Cruz, Rosalinda Tapia-López, and Juan Núñez-Farfán. "Tropane alkaloids and terpenes synthase genes of Datura stramonium (Solanaceae)." PeerJ 9 (June 15, 2021): e11466. http://dx.doi.org/10.7717/peerj.11466.

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Background Plants have evolved physical–chemical defense to prevent/diminish damage by their enemies. Chemical defense involves the synthesis’ pathways of specialized toxic, repellent, or anti-nutritive metabolites to herbivores. Molecular evolutionary studies have revealed the origin of new genes, acquisition and functional diversification along time in different plant lineages. Methods Using bioinformatic tools we analyze gene divergence of tropane alkaloids (TAs) and terpene synthases (TPSs) in Datura stramonium and other species of Solanaceae; compared gene and amino acids sequence of TAs and TPSs on genomes, cDNA and proteins sequences of Viridiplantae. We analyzed two recently assembled genomes of D. stramonium (Ticumán and Teotihuacán), transcriptomes of Datura metel and genomes of other Solanaceae. Hence, we analyzed variation of TAs and TPSs to infer genes involved in plant defense and plant responses before stress. We analyzed protein modeling and molecular docking to predict interactions between H6H and ligand; we translated the sequences (Teo19488, Tic8550 and Tic8549) obtained from the two genomes of D. stramonium by using Swiss-Model and Ramachandran plot and MolProbity structure validation of Teo19488 protein model. Results For TAs, we detected an expansion event in the tropinone reductase II (TRII) and the ratio synonymous/non-synonymous substitutions indicate positive selection. In contrast, a contraction event and negative selection was detected in tropinone reductase I (TRI). In Hy-oscyamine 6 b-hydroxylase (H6H), enzyme involved in the production of tropane alkaloids atropine and scopolamine, the synonymous/non-synonymous substitution ratio in its dominion indicates positive selection. For terpenes (TPS), we found 18 DsTPS in D. stramomiun and seven in D. metel; evolutionary analyses detected positive selection in TPS10.1 and TPS10.2 of D. stramonium and D. metel. Comparison of copies of TPSs in D. stramonium detected variation among them in the binding site. Duplication events and differentiation of TAs and TPSs of D. stramonium, as compared to other Solanaceae, suggest their possible involvement on adaptive evolution of defense to herbivores. Protein modeling and docking show that the three protein structures obtained of DsH6H from Teo19488, Tic-8550 and Tic8549 maintain the same interactions and the union site of 2OG-FeII_Oxy with the Hy-o ligand as in 6TTM of D. metel. Conclusion Our results indicate differences in the number of gene copies involved in the synthesis of tropane alkaloids, between the genomes of D. stramonium from two Mexican populations. More copies of genes related to the synthesis of tropane alkaloids (TRI, TRII, H6H, PMT) are found in D. stramonium as compared to Viridiplantae. Likewise, for terpene synthases (TPS), TPS-10 is duplicated in D. stramonium and D. metel. Further studies should be directed to experimentally assess gain (overexpression) or loss (silencing) of function of duplicated genes.
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Moyano, E., K. Jouhikainen, P. Tammela, J. Palazon, R. M. Cusido, M. T. Pinol, T. H. Teeri, and K. M. Oksman-Caldentey. "Effect of pmt gene overexpression on tropane alkaloid production in transformed root cultures of Datura metel and Hyoscyamus muticus." Journal of Experimental Botany 54, no. 381 (January 2, 2003): 203–11. http://dx.doi.org/10.1093/jxb/erg014.

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Chukunda, F. A., R. E. Baraka, and G. J. Umoren. "In-vitro evaluation of Datura metel leaves for potential antifungal activity against Lasiodiplodia theobromae Pat." Microbiology Research International 7, no. 2 (June 2019): 10–16. http://dx.doi.org/10.30918/mri.72.19.011.

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Turupadang, Welly, Ichsan Sebastian, Nur Alim K, Bagus Rachmad, and Komang Yogatama. "ANALISIS METODE PENGGALIAN PADA MATERIAL LUNAK DENGAN MENGGUNAKAN PC 2000 HINGGA PC 4000 DI TAMBANG LATI, PT BERAU COAL." Prosiding Temu Profesi Tahunan PERHAPI 1, no. 1 (March 29, 2020): 103–12. http://dx.doi.org/10.36986/ptptp.v1i1.54.

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ABSTRAK Tambang Lati merupakan bukaan pit terbesar yang dioperasikan oleh PT Berau Coal (PT BC) dengan target produksi batubara pada tahun 2019 sebesar 14,2 juta Metrik Ton (M/T) dan Stripping Ratio (SR) 12,5. Untuk memenuhi target produksi tersebut, maka diperlukan pengembangan lokasi baru dengan total luas bukaan sekitar 187 ha. Distribusi luasan tersebut meliputi 61% atau sekitar 114 ha merupakan area pengembangan pit berupa material lunak / rawa dengan estimasi volume yang harus dipindahkan sekitar 14 juta Bank Cubic Meter (BCM), sedangkan sisanya merupakan morfologi area perbukitan gelombang rendah – sedang, hal ini dicirikan adanya dataran luas dengan perbukitan di sekitarnya. Ketersediaan alat gali dan muat yang besar (PC 2000 – PC 4000) di Lati mengakibatkan jumlah material untuk kebutuhan timbunan perlapisan jalan maupun front loading di area rawa (layering) yang digunakan menjadi lebih besar dari perencanaan awal. Hal ini mempengaruhi Stripping Ratio (SR) yang sangat signifikan dan tingkat keekonomisan Tambang Lati PT Berau Coal. Evaluasi dilakukan dengan menggunakan data material insitu (tanah lunak / rawa) yang diperoleh dari hasil pemboran Standard Penetration Test (SPT). Penampang atau profil material lunak/ rawa dapat dikelompokkan berdasarkan data hasil pemboran ini, sehingga diperoleh distribusi penyebarannya dan dapat ditentukan secara vertikal maupun horizontal. Distribusi data penampang atau profil material lunak/rawa digunakan pada analisis geoteknik yang dikombinasikan terhadap aspek keselamatan dan operasional dari unit yang digunakan serta dilakukan percobaan langsung di lapangan selama 2 bulan pada lokasi yang acak. Penelitian ini mengevaluasi tingkat kestabilan lereng material lunak/endapan rawa, optimalisasi metode penggalian serta layering sehingga dapat mengakomodasi berbagai kepentingan, khususnya aspek keselamatan dan keekonomisan tambang. Hasil penelitian menunjukkan bahwa loading material lunak / rawa yang mengkombinasikan hasil kajian geoteknik dan aspek operasional dapat bersinergi sehingga operasional penambangan dapat dilakukan secara aman, efisien dan ekonomis dengan menggunakan alat besar (PC2000 – PC4000) yang tersedia di Lati Mine Operation. Kata kunci : Tambang Lati, Tanah Lunak, Rawa, PT Berau Coal, Stripping Ratio, Standard Penetration Test, Loading rawa, PC 2000, PC 2500, PC 3600 dan PC 4000. ABSTRACT Lati Mine Operation is the largest open-pit mining operated by PT Berau Coal (PT BC) with a coal production target in 2019 of 14.2 million Metric Tons (M / T) and Stripping Ratio (SR) 12.5. To meet the production target, it is necessary to develop a new location with a total open-pit area of around 187 ha. 61% or around 114 ha of the area are development zones consisting of 14 million Bank Cubic Meters (BCM) of soft materials, while the rest is the morphology of low-moderate hills, this is characterized by a vast plain surrounded by hills. The availability of large excavator and hauler equipment (PC 2000 - PC 4000) to move the overburden materials causes the amount of material for layering needs exceeds the initial plan. This condition will affect Stripping Ratio (SR), which has a significant effect on the economic level of Lati Mine. An evaluation is carried out using insitu data (soft materials) obtained from the results of the Standard Penetration Test (SPT) drilling. Cross section of the soft materials can be grouped by drilling data, so that distribution is obtained and can be vertically or horizontally determined at the Lati mine site. Cross-sectional or soft materials profiles data distribution are then used in the geotechnical analysis combined with the safety and operational aspects of the used-units which had field trial for 1 month at many random locations. This study evaluated the stability of soft materials and the optimization of digging and layering methods so that it can accommodate various interests, especially the mining safety and economic aspects. The results show that soft materials loading which combines the results of geotechnical studies and operational aspects can synergize so that mining operations can be carried out safely, efficiently and economically by large equipment available in Lati Mine Operation. Keywords : Lati Mine Operation, Soft Material, PT Berau Coal, Stripping Ratio, Standard Penetration Test, Soft Material Loading, PC 2000, PC 2500, PC 3600 and PC 4000.
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Dissertations / Theses on the topic "Datura metel PMT"

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Naik, Tanushree. "Isolation And Identification of Tropane Alkaloid Producing Endophytic Fungi from Datura Metel L., And Studies on Colletotrichum Boninense Recombinant Putrescine N-mehtyltransferase." Thesis, 2016. http://etd.iisc.ernet.in/handle/2005/2713.

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Datura metel is a herbaceous plant found in almost all tropical parts of the world. It belongs to the family Solanaceae whose members, viz. Duboisia, Atropa, Hyoscyamus and Datura plants are known to produce tropane alkaloids- hyoscyamine and scopolamine which are most noted for their therapeutic use as anti-cholinergic agents. Since these alkaloids are produced in very low amounts in plants, alternative sources and methods of production for these alkaloids have been crucial in meeting the demands for these drugs. Endophytic fungi inhabiting a plant may have the potential to produce the same compounds as the host plants. The aim of the present study was to search for tropane alkaloid producing endophytic fungal isolates from Datura metel. Eighteen endophytic fungi were isolated from various tissues of Datura metel and screened for the presence of three tropane alkaloid biosynthetic genes- putrescine N-methyltransferase (PMT), tropinone reductase I (TRI) and hyoscyamine 6β-hydroxylase (H6H) using PCR-based screening approach. Six endophytic fungal isolates were found to possess the PMT, TR1 and H6H genes. The fungi were identified using molecular taxonomy as Col letotrichum boninense, Phomopsis sp., Fusarium solani, Col letotrichum incarnatum, Col letotrichum siamense and Col letotrichum gloeosporioides and the identity was confirmed using colony and spore morphology. The production of tropane alkaloids hyoscyamine and scopolamine by the fungi has been ascertained using various techniques like TLC, HPLC and ESI-MS/MS by comparison with the authentic reference standards. The amount of tropane alkaloids produced by all six fungi in liquid cultures was quantified using HPLC analysis. Among the six tropane alkaloid-producing fungi Col letotrichum incarnatum gave the highest yields of hyoscyamine and scopolamine which were 3.906 mg/L and 4.13 mg/L, respectively. With an aim to characterize the tropane alkaloid biosynthetic genes in these fungi, the PMT gene was isolated from five of the endophytic fungi- Col letotrichum boni-nense, Fusarium solani, Col letotrichum incarnatum, Col letotrichum siamense and Col-letotrichum gloeosporioides for the first time and the sequence analysis showed high ho-mology (98%) to the Datura metel PMT cDNA. The gene was found to be devoid of introns in the fungi. Further phylogenetic analysis of the full length PMT sequence from the fungi strongly supports the hypothesis of horizontal gene transfer between the host plant and endophytic fungi. For further in detail characterization of fungal PMT, the Col letotrichum boninense PMT gene was taken as a representative. CbPMT gene was cloned in pRSET A expres-sion vector and heterologously expressed in E. coli and biochemically characterized. For optimal yield of soluble protein upon heterologous expression different conditions such as IPTG concentration, temperature and time post induction were optimized. Optimal yield was obtained by inducing the culture by 0.25 mM IPTG once it had reached and O.D. of 0.6 and incubating at 37◦ C for 3 h. The recombinant CbPMT enzyme expressed as histidine tagged fusion protein was purified using Ni-NTA affinity chromatography. Gel elution studies were carried out to determine molecular weight of the protein and it was found that the protein exists as a homodimer in solution with some amount also present as a monomer. Catalytic activity of the purified recombinant enzyme was studied for its dependence on both substrates putrescine as well as S-adenosylmethionine (SAM). The Km and Vmax values for putrescine were found to be 464 µM and 18.55 nkat/mg, respectively, while those for S-adenosylmethionine were found to be 628 µM and 18.63 nkat/mg, respectively. Optimum temperature for activity was found to be 37◦ C and optimum pH range was found to be 8-9. Fluorescence spectroscopy was used to study the binding affinity of both the sub-strates to the enzyme. Fluorescence quenching data for each substrate was analysed by using a nonlinear regression curve fit and Kd values were found to be 0.309 mM for pu-trescine and 0.118 mM for SAM, respectively. Circular dichroism spectrum of the enzyme indicated a pattern typical for alpha helix in the secondary structure. Binding of either substrate led to increase in ellipticity of the protein. Fluorescence quenching studies with collisional quenchers- acrylamide, potassium iodide, and cesium chloride indicated that the native protein is folded in a conformation that allows tryptophan residues to be acces-sible for quenching. The fraction of tryptophan residues (fa ) accessible for quenching by acrylamide (1.06) was found to be higher than that for potassium iodide (0.54) while that cesium ions was the least (0.38). The neutral quencher acrylamide could access all the tryptophans meaning that none of tryptophans are completely buried inside hydrophobic cores. the differential accessibility to the charged quenchers, however, indicates that more of the tryptophans are surrounded by positively charged amino acids. The unfolding of the protein was studied with the aid of chaotropic agents guanidine-HCl and urea and thermodynamic parameters were determined. The denaturant m-values were found to be 2.313 kcal/mol/M for Gdn-HCl and 2.345 kcal/mol/M for urea respectively. The free energy of unfolding was estimated to be 2.635 kcal/mol for Gdn-HCl and 4.630 kcal/mol for urea. Since no reports are available about the thermodynamics of folding and unfolding of PMT from any plant source, this study contributes towards the understanding of protein stability. Although a lot of reports are available on the biochemical characterization of PMT from different plant sources, the crystal structure of PMT is not yet available. In the current work, homology based modelling studies on CbPMT were carried out to get some idea about the protein tertiary structure. Homology based modelling studies showed that a significant amount of protein is present as α-helices which are present on the surface while the β-sheets are present in the interior of the protein. Each monomer of the protein is capable of binding both the substrates and hence the dimerization property of the enzyme could be a purely structural one leading to more stability and solubility of the protein. In conclusion, this study has shown for the first time that endophytic fungi have significant potential to be used for tropane alkaloid production and six such fungal strains have been identified. Although the production of tropane alkaloids by endophytic fungi is not very high, it can be scaled up by over-expressing the biosynthetic gene putrescine N-methyltransferase in the highest producer- Col letotrichum incarnatum to further increase the yield. These endophytic fungi have significant potential to be applied in fermentation technology to meet the demands for these drugs economically.
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Book chapters on the topic "Datura metel PMT"

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Michnik, Monika, and Karol Dzięgielewski. "Analiza obiektów nieruchomych / Analysis of the immobile sources." In Cmentarzysko w wczesnej epoki żelaza w Świbiu na Górnym Śląsku. Tom 2, 24–49. Wydawnictwo Profil-Archeo, 2022. http://dx.doi.org/10.33547/swibie2022.2.2.

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At the Early Iron Age cemetery in Świbie 548 archaeological features were identified, including 420 inhumation graves, 28 biritual graves (inhumation graves with cremation burials) and 100 cremation graves (including 49 urned cremations, 50 cremations in pits and one urn-pit grave). None of the 420 inhumation graves revealed a fully preserved skeleton (the only bone fragments to survive were those next to bronze objects). The grave pits were elongated oval or rectangular in outline, with dimensions averaging between 200 and 300 cm. They usually became discernible immediately after the removal of the undergrowth. Their depth averaged between 40 and 60 cm, although there were also deeper graves (up to 150 cm). The longitudinal grave pits were usually oriented with the longer axis on a N-S line. The deceased were laid in an upright position with their heads to the north and with the arms extended along the body, as indicated by bone fragments or the distribution of costume-related artefacts (mainly metal, but also glass). Each grave likely contained the remains of a single individual, but the patchiness of the osteological data from the cemetery may render this conclusion not entirely correct. Most of the graves in the cemetery had internal structures, usually in the form of stone settings, and less often stone pavements or wooden linings, biers, and coffins. The stone pavements were most often single-layered and were laid loosely (less often compactly) over the entire grave or in clusters over a selected part of it. In 25 graves, multi-layered constructions were discovered. Stone settings were built at the lower levels of the pits, usually immediately adjacent to the burial. They usually consisted of single stones or clusters of stones placed on the longer sides of the pit, or at its northern and southern edges, and they were rarely compact structures. One of the most important discoveries in the cemetery are traces and remains of internal wooden structures. These took two forms: elements related to the protection of the grave pit (lining was found in 10 graves) and those related directly to the burial (remains of wooden biers or boxes/coffins were found in 43 graves). They were made of oak wood. In addition, other organic remains (such as straw and moss) were found, probably serving as a lining for the biers before the body was placed on them.
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İsmail Tosun, Yildirim. "Landslide Analysis over Creep Theory - Crack Propagation of Shale Slopes in Şırnak Asphaltite Coal Mine Site 1 and 2." In Landslides [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101035.

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The soft rock and wet slopes increase landslides over 50 m long creep slide and risk assessment for long steep slide in Şırnak open-pit coal mining should be searched in asphaltite quarries. The Avgamasya quarries No1 and 2 at critical depths and road bench sites in Şırnak, reaching over 120 m height with 60–65° shale slopes, developing major creep factors and other factors for landslide in the deep quarry locations is resulting debris rock falling or free sliding. The pore pressure measurements by measurements of water levels in four wells and water flow counting as the mining safety in recent years. This research provided rock slope stability patterns and crack propagation control of the hazardous location and formation cracks. The stages of creep experimentation explored the geophysical characteristics and thaw and freeze testing of rock samples. For this aim, two different long sliding areas with similar geoseismical conditions, two main analyzing methods, and patterns of researches were developed. Firstly, data on crack propagation in situ rock shale faces over certain time periods were determined. Displacement measurements over highly saturated shale—limestone contacts over the base of crack counting in a meter scale such as Rock Quality Designation (RQD) scoring of drilling logs. Secondly, hydrological water level logs were taken into consideration. On the other hand, due to that creep effect over freeze crack propagation unseen cause instability over wet sliding surfaces over 50 m, long sliding surface matter over slopes, poly linear or circle type creep sliding or rock tumbling falling failure types, and GEO5 slope stability, slice analysis will be advantageous instead of Finite Element Method (FEM) method.
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Conference papers on the topic "Datura metel PMT"

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Liu, Hanru, Jinjia Wei, and Zhiguo Qu. "The Interaction of Porous Metal Coating With the Near Wake of Bluff Body." In ASME 2012 Fluids Engineering Division Summer Meeting collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/fedsm2012-72170.

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The flow around a circular cylinder with porous metal coating (PMC) is numerically investigated based on an approach of unsteady Reynolds Averaged Navier-Stokes (URANS) at subcritical Reynolds number. The model validation is carried out through comparison with some available experimental results in the literatures. It is found that the simulated results in the present work coincide well with the experimental data. The interaction of PMC with the near wake of circular cylinder such as streamline, vorticity and shear stress are studied in detail. The result reveals that PMC has capability of manipulating the wake flow so that the near wake of PMC cylinder is substantially different from that of smooth one. In addition, the fluctuations of aerodynamic forces are mitigated effectively. Varying the thickness of porous metal coating causes various velocity distributions and aerodynamic performance of bluff body. When the thickness is appropriate, the drag forces can be reduced to a certain extent. It is expected that the modification of flow characteristic and aerodynamic forces also produces the suppression of flow-induced noise generated by bluff body. These studies on wake flow and analysis of its relationship to flow-induced noise will be useful to understand the mechanism of controlling bluff body flow-induced noise by using PMC and to optimize the PMC for controlling flow and flow-induced noise.
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Andrade, Luciano G. D., Ezequiel C. P. Pessoa, Alexandre Q. Bracarense, Weslley C. Dias, Leandro F. Ribeiro, and Stephen Liu. "The Effect of Base Metal and Core Rod Carbon Content on Underwater Wet Weld Porosity." In ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-20877.

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Porosity is a common defect observed in underwater wet welding. Several research programs have been developed to understand how pores form in order to mitigate the problem. No superficial pores and a limited number of internal pores (based on size) are important requirements to classify underwater wet welds according to the American Welding Society – AWS D3.6M standard. The main objective of this work is to study the effect of base metal and core rod carbon content on weld metal porosity. A pressure chamber with 20 atmospheres capacity was used to simulate depth with fresh water. To perform the welds, a gravity feeding system able to open an electric arc and deposit the weld automatically was used. Beads-on-plate were made using Direct Current Electrode Negative (DCEN) configuration on two base metals with different carbon contents (C2 – 0.1 wt. pct. and C7 – 0.7 wt. pct.) at 50 meters water depth. Commercial E6013 grade electrodes were used to deposit the welds. These electrodes were produced with core rods with two different carbon content (E2 – 0.002 wt. pct. and E6 – 0.6 wt. pct.) and painted with varnish for waterproofing. Samples were removed from the beginning, middle and end of the BOP welds and prepared following metallographic techniques including macroetching and image analysis for weld porosity. A data acquisition system was used to record current, voltage and welding time at 1.0 kHz rate. The porosity measurements indicated an increase of about 85% and 70% when E6 electrodes were used instead of E2 electrode on C2 and C7 steel plates, respectively. Simultaneously, the increase in porosity was followed by an increase in short circuiting events, an increase in weld bead penetration and a decrease in welding voltage. These observations seem to confirm, a direct effect of carbon content of the core rod on weld metal porosity and that porosity is associated with the CO reaction that can occur during metal transfer in that molten droplets carry gas bubbles to the welding pool. On the other hand, the increase of carbon content in the base metal was seen to decrease the porosity in the weld metal. This result can be related with the decrease in penetration observed when changing C2 to C7 plates. The smaller participation of carbon from the base metal in the weld pool reactions should then reduce the CO formation and, consequently, the amount of pores in the weld.
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Amano, R. S., J. Xie, E. K. Lee, and P. K. Rohatgi. "CFD Simulation and Experimental Validation of Solidification of Metal Matrix Composites (MMC) in the Presence of Cooled Fibers." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-60290.

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A new experimental configuration for the casting of metal matrix composites (MMCs) using Al-4.5 wt pct Cu have been used to obtain finer microstructures around the fiber reinforcement. The new configuration allows the fibers to be extended out the mold and cooled by a heat sink. By doing so, the solidification can be made more rapid, and more primary alpha-aluminum phase can be formed on the surface of the fibers. It is believed that this can lead to improvement in the properties of the composite. CFD simulation of the solidification of Al-4.5 wt pct Cu in the casting process has been carried out by using commercial CFD code. Parametric studies on the effects of different processing parameters on solidification time have been simulated using the CFD code. These parameters include, but are not limited to, the pouring temperature of the liquid melt, sink temperature, fiber length extended out of the mold, the mold initial temperature, fiber conductivity, applied pressure, and fiber bundle diameter. Selected simulation results are compared with the available experimental data obtained from the UWM Center for Composites.
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Howe, Dennis G. "CD Error Characterization; Differences Between CD-ROM and Writable CD." In Optical Data Storage. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/ods.1994.ma4.

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Read only Compact Discs (CDs), such as the CD-ROM and Digital Audio CD, are made by concurrently forming the plastic disc and the spiral track of pits that represent the data carried on the surface of the disc via an injection molding operation, and subsequently applying a reflective metal layer in a vacuum coating step and a protective polymer layer via spin coating. The original data that is replicated on these "pressed" CDs is carefully written on a master disc (that is used to form the injection molding tool) using a precision master laser writer that is housed in a very clean environment. On the other hand, writable CDs, such as the CD-R and PhotoCD, are made by first using injection molding to form a plastic disc that has a continuous spiral (tracking) groove on one surface and then sequentially coating that grooved surface with a vacuum deposited dielectric layer, a spin coated organic "pit-forming" layer, a vacuum coated metal reflector layer and a spin coated organic protective layer. Although the spiral tracking groove that is replicated on the surface of the writable CD's molded plastic substrate is initially written on a master disc using essentially the same precision laser writer that was used to create the pressed CDs' master discs, the marks that correspond to the user digital data carried by the writable CD are written one at a time via an optical CD disc drive that is housed in an ordinary environment.
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Shkolnikov, Vladimir M., Gabriel J. Hostetter, David K. McNamara, Joseph R. Pickens, Stanley P. Turcheck, and Bruce G. I. Dance. "Advanced Hybrid Joining Technology." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-79769.

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The paper summarizes results of an engineering investigation on advanced joining technology for hybrid (composite-metal) structures. Polymer Matrix Composites (PMC) used in structural applications are known to reduce structure weight, lower life-cycle cost and, in case of a floating platform, improve the deadweight/displacement ratio. While beneficial, PMC applications for large hull structures have certain limitations in size and volume of seamless structural component without using joints. A hybrid hull that consists of both metal and composite structural members potentially enables desirable enhancements of structural efficiency, but robust joining between those heterogeneous structures must be employed. A recently completed feasibility study has been performed involving a novel hybrid joining concept-technology based on a combination of conventional adhesive bonding with novel metal surface preparation. Computer simulation of the joint structural behavior and failure, development of a material processing procedure based on adaptation of Vacuum-Assisted Resin Transfer Molding (VARTM) process to manufacturing of a large hybrid structure, fabrication of pilot joint test articles, and tensile testing of those to failure, have been performed as part of the feasibility study. Two sets of the hybrid joint were tested, the novel joint being developed and its conventionally bonded analogue without the novel surface preparation considered as a base-line joint. The tests resulted with 48%-increase of load-bearing capability of the novel joint and a good match between generated computed and experimental data.
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Abdoli, Mehrsima, M. R. Ay, Alireza Ahmadian, and Habib Zaidi. "Metal Artifact Reduction in CT-Based Attenuation Correction of PET Data Using the Virtual Sinogram Concept." In 2009 3rd International Conference on Bioinformatics and Biomedical Engineering (iCBBE). IEEE, 2009. http://dx.doi.org/10.1109/icbbe.2009.5163044.

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Espina-Herna´ndez, J. H., F. Caleyo, J. M. Hallen, A. Lo´pez-Montenegro, and E. Pe´rez-Baruch. "Influence of Remanent Magnetization on Pitting Corrosion in Pipeline Steel." In 2010 8th International Pipeline Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ipc2010-31389.

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These days, in-line inspections based on the magnetic flux leakage (MFL) principle are routinely used to detect and size metal loss and mechanical anomalies in operating oil and gas pipelines. One of the characteristics of the MFL technology is that after the inspection, the pipeline wall shows a remanent magnetization. In this work, the influence of the magnetic field on pitting corrosion in pipeline steel is studied. Pitting corrosion experiments have been carried out on samples of an API 5L grade 52 steel under a magnetization level of the same order of magnitude of the remanent magnetization in the pipeline wall after the MFL inspection. The samples were magnetized using rings of the investigated steel. The closed magnetic circuit configuration used in this study survey guaranteed that the samples kept the same magnetization level during the complete duration of the conducted experiments. This experimental setup was used in order to reproduce the conditions observed in MFL-inspected pipelines in which the magnetic field was confined to the pipe wall thickness. Immediately after magnetization, the investigated samples were subjected to pitting by immersing them in a solution with dissolved Cl− and SO42− ions. The pitting experiments were conducted for exposure times of 7 days. Non-magnetized specimens were used as control samples. The depths of the pits induced in the investigated samples were measured using optical microscopy. The maximum pit depth of each sample was recorded and used to conduct extreme value analysis of the pitting process in the magnetized and non-magnetized specimens. The results of this investigation indicate that the magnetic field confined within the pipeline wall has a significant influence on the pitting corrosion process. The statistical assessment of the pitting corrosion data collected during this study shows that the magnetic field reduces the average depth of the pit population. It also reduces the extreme pit depth values that can be predicted from the maximum values observed in the magnetized samples, with respect to the non-magnetized control samples. Scanning electron microscopy observations show that the magnetic field alters the pit morphology by increasing the pit opening (mouth). It is shown that the observed reduction in the pit depth when a magnetic field is confined to the volume of the corroding material can be explained based on the behavior of the paramagnetic corrosion products under the influence of the local magnetic field gradients produced inside and within the immediate vicinity of stable pits.
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8

Lee, E. K., R. S. Amano, J. Xie, and P. K. Rohatgi. "Parametric Study of MMC Solidification in the Presence of Cooled Fibers: Numerical Simulation and Experimental Validation." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56075.

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A new experimental configuration for the casting of metal matrix composites (MMCs) using Al-4.5 wt pct Cu has been used to obtain finer microstructures around the fiber reinforcement. The new configuration allows fibers to be extended out of the mold and cooled by a heat sink. By doing so, solidification can be sped up and more primary alpha-aluminum phase can be formed on the surface of the fibers. It is believed that this can lead to improved material properties of the composite. A simulation study of the solidification process has been carried out to examine the effects of different processing parameters on the cooling rate during the casting of MMC. Among these parameters include the pouring temperature of the liquid melt, sink temperature, fiber length extended out of the mold, fiber conductivity, mold initial temperature, mold conductivity, applied pressure, mold wall thickness, and fiber bundle diameter. Selected simulation results are compared with the available experimental data obtained from the UWM Center for Composites.
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9

Thornley, David John, Kareena McCrindle, Stephen Rayner, Jonathan Sharpe, Czeslaw Pienkowski, and Carl Phillips. "The Application of Additional, Off-Line, Analysis Techniques to PCM Monitor Results to Aid the Efficient and Cost Effective Repackaging of Legacy PCM Wastes Containing Calcium and Potentially Plutonium Fluoride." In ASME 2009 12th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2009. http://dx.doi.org/10.1115/icem2009-16034.

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There are a small number of legacy, orphan waste, PCM (Plutonium Contaminated Material) drums at Sellafield Site containing calcium metal potentially contaminated by plutonium (Pu), some of which may be in the form of plutonium fluoride (PuF4). These drums were measured on a TRU-D® PCM Drum Monitor to give a Nuclear Safety value for the Pu mass based on Neutron Coincidence Counting (NCC) and the Pu isotopic composition measured for each drum using a germanium detector based High Resolution Gamma Spectrometry system. In some circumstances the presence of Pu in the form of PuF4 can cause a significant overestimate of the measured Pu mass. This is as a result of alphas emitted by the spontaneous decay of Pu isotopes interacting with light elements such as fluorine, resulting in the emission of “random” (alpha, n) neutrons. The potential overestimate may be very large for total neutron counting based systems if the presence of PuF4 is not accounted for in the system calibration. However, significant quantities of PuF4 may also result in overestimates for NCC systems due to potentially large statistical uncertainties in the measurement results caused by accidental coincidences involving the random (alpha, n) neutrons. Therefore in some circumstances, less pessimistic measurements may be obtained from the total neutron count, corrected using the measured “PuF4 ratio”. Standard TRU-D® Drum Monitor measurements of the calcium containing drums were carried out by plant operators. Relevant data was then downloaded from the plant instrument allowing additional off-line techniques to be applied to the high resolution gamma spectra associated with each drum. These spectra are routinely generated as part of the standard TRU-D® PCM Drum Monitor measurement. This analysis was based on the patented PuF4 analysis technique developed by VT Nuclear Services personnel to determine the mass ratio of Pu in the form of PuF4 to total Pu mass using the PuF4 reaction gammas and standard Pu gammas observed in the gamma spectrum. This additional, off-line analysis reduces the potential overestimate in the Pu Nuclear Safety Mass associated with each drum aiding the repackaging of the legacy material into Bull Pit cans. Following this, similar measurements and off-line analysis was carried out for the filled Bull Pit cans using a TRU-D® PCM Piece Monitor set up and commissioned specifically for this task. The further analysis results allowed the Bull Pit cans to be efficiently and cost effectively packed in 200 litre drums. The resulting new 200 litre drums were then measured using a standard, routinely operated TRU-D® PCM Drum Monitor for final sentencing (again taking into account off-line PuF4 analysis) to allow safe and secure storage. This paper describes the work carried out and the additional off-line PuF4 analysis techniques and how they have been applied within the exacting demands of Nuclear Safety in support of legacy material treatment and ultimate safe storage.
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Adair, David, Michael Kirka, and Daniel Ryan. "Additive Manufacture of Prototype Turbine Blades for Hot-Fired Engine Performance Validation Trials." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90966.

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Abstract Additive manufacturing (AM), also known as 3D printing, is a rapidly developing technology with tremendous potential in both developmental and production applications. Solar Turbines Incorporated is committed to AM technology for gas turbine applications. The ability to metal 3D print novel designs of turbine blades capable of actual turbine engine operation would effectively reduce design validation cycle time, and allow acquisition of key performance data early in a design campaign. In support of Solar’s advanced manufacturing development and ongoing engine efficiency improvement goals, Solar initiated a project to print a full set of Mercury™ 50 stage 2 turbine blades to be run in a development engine. Solar leveraged years of experience with design and serial production of AM components in support of this project. A significant challenge faced when printing turbine blades is producing metal with mechanical properties sufficient to withstand the rigors of engine operation. As a rotating component within the hot section of the engine, turbine blades experience high centrifugal and pressure loads at elevated temperatures. After investigation of possible alloys capable of meeting the requirements of the Mercury™ 50 design envelope, the gamma prime (γ’) strengthened nickel superalloy Inconel™ 738LC was selected to provide the best opportunity for successful development engine testing. Solar partnered with Oak Ridge National Laboratory (ORNL) to produce the Inconel™ 738LC blades with Electron Beam Melting (EBM) powder bed fusion process. Once a rough blade shape was printed, the fir-tree attachment, blade tip shroud, and air flow path surfaces were finished using both conventional and non-conventional machining processes. In-process monitoring, metallurgical evaluations, mechanical testing, and non-destructive inspection techniques were used to validate the printed blade material integrity and conformance to geometric design intent. Planned future activities include assembly of the AM blades onto a disk for spin pit testing to validate the mechanical integrity and design margin of the blades. The final phase of the project will be to install the bladed disk assembly into a Mercury™ 50 engine at Solar Turbines to conduct a series of hot-fired engine performance tests.
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Reports on the topic "Datura metel PMT"

1

Eilerts. L52026 Improved Prediction of Burnthrough for In-Service Welding. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), August 2002. http://dx.doi.org/10.55274/r0011153.

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Experiments were conducted to evaluate the effect of pressure on burnthrough risk.� The results indicate that hoop stress has a significant effect for thin-wall pipe.� The experimental data was used to develop and evaluate an alternative burnthrough prediction approach that accounts for pressure in the pipe.� The approach that was developed assumes that the volume of heated metal under the arc behaves similar to an area of metal loss caused by corrosion pitting.� An equivalent pit size is determined from the pipe diameter and wall thickness and the calculated weld penetration.� The predicted burst pressure (i.e., the pressure limit) is then determined using RSTRENG.� While this approach was shown to be relatively accurate for the experimental welds that were made, it does not consider the removal of heat by the contents and it was evaluated for a limited range of conditions.
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2

Gadd, M. G., J. M. Peter, T A Fraser, and D. Layton-Matthews. Paleoredox and lithogeochemical indicators of the environment of formation and genesis of the Monster River hyper-enriched black shale showing, Yukon. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328004.

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Northern Yukon hosts occurrences of Middle Devonian hyper-enriched black shale (HEBS) Ni-Mo-Zn-platinum-group element-Au-Re mineralization, including the Monster River showing in the Ogilvie Mountains. This mineralization has been documented predominantly in the Paleozoic Richardson trough; however, the Monster River showing is atypical, occurring within the Blackstone trough, more than 200 km to the west on the southern margin of the Yukon block. The ambient paleoredox conditions of the marine water column and sediments may be primary controlling factors in HEBS formation. We use major and trace element lithogeochemistry to better understand ambient paleoenvironmental redox conditions through the application of robust redox proxies to HEBS mineralization and host rocks. Uniformly negative Ce anomalies (0.6-0.9) indicate that the water column was predominantly suboxic throughout the deposition interval, even during HEBS mineralization. Although there is a strong terrigenous influence on the rare earth element-yttrium (REE-Y) abundances of the sedimentary rocks, superchondritic Y/Ho ratios (>27) indicate that seawater contributed REE-Y to the host rocks and HEBS. High (>10) authigenic Mo/U ratios indicate that a Fe-Mn particulate shuttle operated in the water column; this is corroborated by negative Ce anomalies and high Y/Ho ratios. The data indicate that metalliferous sedimentary rocks formed by hydrogenous metal enrichment (e.g. Ni, Mo, Pt) caused by ferromanganese oxyhydroxide particulate shuttling as chemical sediments; moreover, the REE- and Mo-based paleoenvironmental indicators suggest a complexly redox-stratified depositional environment with an abundant supply of metals, metalloids, and sulfur.
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3

Hodul, M., H. P. White, and A. Knudby. A report on water quality monitoring in Quesnel Lake, British Columbia, subsequent to the Mount Polley tailings dam spill, using optical satellite imagery. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330556.

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In the early morning on the 4th of August 2014, a tailings dam near Quesnel, BC burst, spilling approximately 25 million m3 of runoff containing heavy metal elements into nearby Quesnel Lake (Byrne et al. 2018). The runoff slurry, which included lead, arsenic, selenium, and vanadium spilled through Hazeltine Creek, scouring its banks and picking up till and forest cover on the way, and ultimately ended up in Quesnel Lake, whose water level rose by 1.5 m as a result. While the introduction of heavy metals into Quesnel Lake was of environmental concern, the additional till and forest cover scoured from the banks of Hazeltine Creek added to the lake has also been of concern to salmon spawning grounds. Immediate repercussions of the spill involved the damage of sensitive environments along the banks and on the lake bed, the closing of the seasonal salmon fishery in the lake, and a change in the microbial composition of the lake bed (Hatam et al. 2019). In addition, there appears to be a seasonal resuspension of the tailings sediment due to thermal cycling of the water and surface winds (Hamilton et al. 2020). While the water quality of Quesnel Lake continues to be monitored for the tailings sediments, primarily by members at the Quesnel River Research Centre, the sample-and-test methods of water quality testing used, while highly accurate, are expensive to undertake, and not spatially exhaustive. The use of remote sensing techniques, though not as accurate as lab testing, allows for the relatively fast creation of expansive water quality maps using sensors mounted on boats, planes, and satellites (Ritchie et al. 2003). The most common method for the remote sensing of surface water quality is through the use of a physics-based semianalytical model which simulates light passing through a water column with a given set of Inherent Optical Properties (IOPs), developed by Lee et al. (1998) and commonly referred to as a Radiative Transfer Model (RTM). The RTM forward-models a wide range of water-leaving spectral signatures based on IOPs determined by a mix of water constituents, including natural materials and pollutants. Remote sensing imagery is then used to invert the model by finding the modelled water spectrum which most closely resembles that seen in the imagery (Brando et al 2009). This project set out to develop an RTM water quality model to monitor the water quality in Quesnel Lake, allowing for the entire surface of the lake to be mapped at once, in an effort to easily determine the timing and extent of resuspension events, as well as potentially investigate greening events reported by locals. The project intended to use a combination of multispectral imagery (Landsat-8 and Sentinel-2), as well as hyperspectral imagery (DESIS), combined with field calibration/validation of the resulting models. The project began in the Autumn before the COVID pandemic, with plans to undertake a comprehensive fieldwork campaign to gather model calibration data in the summer of 2020. Since a province-wide travel shutdown and social distancing procedures made it difficult to carry out water quality surveying in a small boat, an insufficient amount of fieldwork was conducted to suit the needs of the project. Thus, the project has been put on hold, and the primary researcher has moved to a different project. This document stands as a report on all of the work conducted up to April 2021, intended largely as an instructional document for researchers who may wish to continue the work once fieldwork may freely and safely resume. This research was undertaken at the University of Ottawa, with supporting funding provided by the Earth Observations for Cumulative Effects (EO4CE) Program Work Package 10b: Site Monitoring and Remediation, Canada Centre for Remote Sensing, through the Natural Resources Canada Research Affiliate Program (RAP).
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