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Journal articles on the topic "Sand cord"
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Bede, Peter, Ronan Walsh, Andrew J. Fagan, and Orla Hardiman. "“Sand-watch” spinal cord: a case of inferior cervical spinal cord atrophy." Journal of Neurology 261, no. 1 (2013): 235–37. http://dx.doi.org/10.1007/s00415-013-7193-7.
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TATE, Takayuki, and Hideyuki TSUKAGOSHI. "Fluid Powered Soft Cord Robot aiming to move in the sand." Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) 2016 (2016): 2A1–04b2. http://dx.doi.org/10.1299/jsmermd.2016.2a1-04b2.
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Kucera, Martin. "Komplementärberatung: Den Faktor Mensch professionell einbinden." kma - Klinik Management aktuell 24, S 01 (2019): S10—S11. http://dx.doi.org/10.1055/s-0036-1595733.
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Sind Mitarbeiter in Veränderungsprozesse nicht eingebunden, verlaufen gute Beratungsansätze oft im Sand. Um das zu verhindern, bietet das Beratungsunternehmen CoSolvia seit neuestem die Komplementärberatung an. Sie führt die Ansätze von Fach- und Prozessberatung zusammen. Im Gespräch mit kma erklärt Geschäftsführer Cord Brüning, wie das funktioniert.
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Levin, Martin A., Lisa L. Cale, and Valerie Lynch-Holm. "The ultrastructure of the abdominal musculature of an orchestid amphipod." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 3 (1990): 464–65. http://dx.doi.org/10.1017/s0424820100159862.
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Orchestia is a genus of amphipod in the crustacean class Malacostraca. The order Amphipoda contains over 6000 species commonly called side swimmers, scuds and beach fleas(1). Most are marine bottom-dwellers utilizing their thoracic legs and posterior abdominal uropods for walking, crawling and swimming. However, some, like those in the genera Orchestia and Hyale are semiterrestrial. These amphipods, commonly referred to as “beach fleas,' “beach hoppers” or “sand fleas” can hop vigorously for great distances (up to 50 times their length) by extending their abdomens and telsons against the sand(2).In our study, the ultrastructure of the dorsal muscle cord of Orchestia grillus was examined. Vogel(3) described the abdominal muscles of Orchestia cavimana as consisting of two groups of muscles: a strong, complex, dorsal muscle cord used mainly for hopping and a group of weaker, ventral, longitudinal and oblique muscles.The specimens were collected in clumps of decaying seaweed and other detritus from the intertidal zone near the high water mark at Avery Point Beach, Connecticut.
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A.G., Narayanaswamy, Meenakshi K., Porchelvan S., Vinoth Kumar J., Bavya S., and SharanyaShre E. S. "Umbilical cord serum lipid profile of healthy neonates- A single center study from rural Tamil Nadu, India." Biomedicine 42, no. 2 (2022): 268–73. http://dx.doi.org/10.51248/.v42i2.1253.
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Introduction and Aim: Umbilical cord lipid profile of neonates might help facilitate the assessment of risk of developing atherosclerotic disorders later in life. This study prospectively measures the cord blood lipid profile of healthy newborn at birth in medical college hospital in rural Tamil Nadu. Material sand Methods: Consecutive full-term newborns (n=105) were enrolled for this study. Umbilical cord blood sample was collected from placental end of the cord immediately after delivery of placenta of each baby and sent to the lab for lipid profile estimation. Results: In the newborns born to non-diabetic mothers, the mean cord blood total serum cholesterol (TC) was 73.31mg %, triglyceride (TGL) was 51.50mg %, high-density lipoproteins (HDL) 24.62 mg % and low-density lipoproteins (LDL) 51.73 mg %. Amongst newborns born to diabetic mothers, the mean TC was 113 mg % (P = 0.001), TGL 98.08mg% (P = 0.045) HDL 28.75 mg% (P = 0.130) LDL 73.48mg% (P = 0.007). Umbilical cord blood lipid profile did not show any significant sex-dependent difference. There was no statistical difference in lipid values between appropriate for gestational age (AGA)and small for gestational age (SGA). Birth weight had a negative correlation to cord blood serum TC and TGL values and showed no correlation to HDL and LDL values. Other parameters including head circumference, length of newborn at birth also showed no correlation to lipid profile. Total cholesterol, TGL and LDL were significantly elevated in newborns born to diabetic mothers. There was no statistical difference in cord blood lipid profile of babies born to mothers who were hypertensive. Conclusion: Infants born to diabetic mothers tend to have significantly elevated lipid values at birth and must be followed regularly later in life to diagnose and treat dyslipidemia and diabetes, to prevent onset of premature atherosclerotic coronary artery disease in this population.
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Selin, Dmitry, Alexander Lebedintsev, Pavel Grebenyuk, and Alexander Fedorchenko. "Ceramics of the Old Bering Sea Culture from the Kozhevnikov Cliff Site (Cape Schmidt): Features of Pottery Technology." Nizhnevolzhskiy Arheologicheskiy Vestnik, no. 2 (June 2024): 161–72. http://dx.doi.org/10.15688/nav.jvolsu.2024.2.8.
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During the excavations of a dugout at the Kozhevnikov Cliff site (Cape Schmidt), N.N. Dikov obtained a collection of pottery vessels of the Old Bering Sea culture (fourteen specimens). The technology of ceramic production was analyzed using the methodology developed by A.A. Bobrinsky. It was determined that potters selected iron-rich clays of two subtypes, differing in the amount of natural sand content, for pottery production. Five recipes for the molding clay were identified, including three unmixed: 1) clay + sand (7 specimens); 2) clay + wool (3 specimens); 3) clay + organic solution (2 specimens); and two mixed – 4) clay + sand + organic solution (1 specimen); and 5) clay + sand + wool (1 specimen). The vessels were made in a base form, and the shape was additionally formed by paddling. On the outer surface of one artifact, a strap handle with an ear for threading a cord was made, and the remaining hole on the inside was patched with a cloth scrap. The surfaces of the vessels were treated by mechanical smoothing with a hard-smooth tool and/or fingers. Firing took place at temperatures above clay calcination and could be done in bonfires or hearths. The heterogeneity of pottery traditions was found among the population living in the dugout. The two identified two-component recipes for molding clay were formed as a result of mixing the adaptive pottery skills of bearers of different traditions of making unmixed recipes for molding clay. This indicates the beginning of cultural integration processes among bearers of different pottery skills that began to occur under the dominance of the tradition of using low-sanded clay of the first subtype and artificial sand addition in a 1 : 1 concentration.
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Bio, Djara Moussa, Laïbi Raoul A., and Christophe Kaki. "Influence of Amenities in the Functioning of a Coastal Sediment Cell with a Moving Barrier: Case of Benin Coastal Segment between Hillacondji and Djondji in the Township of Grand Popo." Journal of Geography, Environment and Earth Science International 10, no. 4 (2017): 1–13. https://doi.org/10.9734/JGEESI/2017/33402.
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The coast of Benin, 125 km long, is part of the overall west African coast, characterized by a narrow strip of coarse and medium sand and by an important coastal transit, which makes it an essentially fragile coastline. This coast also suffers from a strong anthropic pressure marked by the presence of port and hotel infrastructures as well as the administrative and private buildings wich disturb sedimentary dynamics of the coastline. The coastal sector between Hillacondji and Grand-Popo, which for a while, is confronted to erosional phenomena of sandy band, which was the subject of the present study. Since 1980s, some short ears were erected on Togo coastline, 2 km far away from the border with Benin (Hillacondji). Since their erection, erosion has been observed on Benin Hillacondji – Djondji coastline, but without being too critical. Following the rehabilitation of these ears in 2012, the erosion phenomena were aggravated on the costal band of Hillacondji - Djondji causing important socio-economic consequences. The purpose of this study was to assess the magnitude of the prevailing coastal erosion on the coastal band of Hillacondji – Djondji using data collected from field surveys and observation, as well as satellite images (Landsat). This study indicated that this section of coast is under a generalized coastal erosion with a significant acceleration since 2012. The coastline retreat over the four last years (between 2012 and 2016) was estimated at 16.46 <em>m/year </em>at <em>Hillacondji</em> beach and at 5.13 <em>m/year </em>at <em>Agoue </em>beach. Only the coast segment between <em>Agoue</em> and <em>Avlo</em>, showssince 1982 a dynamic balance followed sometimes by exceptional episodes of erosion.The <em>Avlo-Djondji </em>is confronted to a disturbance related to the mobility of the Mono River (embouchure) which is accompanied of violent and very destructive erosion phenomena.
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LOWRY, J. K. "Talitrid amphipods from ocean beaches along the New South Wales coast of Australia (Amphipoda, Talitridae)." Zootaxa 3575, no. 1 (2012): 1. http://dx.doi.org/10.11646/zootaxa.3575.1.1.
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The sand-hopper Bellorchestia mariae sp. nov. is described from Honeymoon Bay on the north coast of Jervis Bay, NewSouth Wales, Australia. It is the sister species of B. richardsoni Serejo & Lowry, 2008 and appears to have a limited dis-tribution from about Narrawallee in the south to northern Jervis Bay. The distribution of B. richardsoni Serejo & Lowry,2008 is extended from Point Ricardo, Victoria, northwards to Ulladulla on the New South Wales coast. A new synonymyis proposed for the sand-hopper Notorchestia quadrimana (Dana, 1852) which includes N. novaehollandiae (1899) andN. lobata Serejo & Lowry, 2008. It is considered to be a wide-ranging species from Shark Bay in Western Australia aroundthe south coast to at least Maitland Bay in central New South Wales. The beach-hopper Orchestia dispar Dana, 1852 isdescribed from Valla Beach in northern New South Wales and moved to the new genus Vallorchestia. This is the first re-cord of V. dispar since its original description 160 years ago. The beach-hopper Platorchestia smithi sp. nov. is describedfrom Brooms Head, New South Wales, Australia. It is common on ocean beaches from Bendalong in the south to Ballina in northern New South Wales. South of Bendalong beach-hoppers on ocean beaches appear to be absent.
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Hountondji, Babilas, Lambert K. Ayitchéhou, François De Paule Codo, and Martin P. Aina. "Innovative Method of Carrying Out Coastal Protection Works: Monitoring Coastal Risks and Soft Solutions in Benin." European Journal of Applied Sciences 13, no. 02 (2025): 176–83. https://doi.org/10.14738/aivp.1302.18325.
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Coastal erosion is a phenomenon of natural or anthropogenic origin that affects many coastal regions around the world. In response to its worsening over time, adaptation strategies have been developed: construction of dikes, operations to re-silt beaches, rock structures, etc. Among these strategies, the establishment of sand dunes is a territorial entity which fluctuates in space and time depending on natural (tide, erosion, sedimentation, etc.) and human factors (dams, etc.). The Beninese dune cord in the sector of the mouth of the Mono River in the commune of Grand Popo is in a state of lamentable degradation: due to anthropogenic pressure, mainly through urbanization, tourism, illegal sand extraction and even all the agricultural activities practiced in the area, something which has favored wind erosion and the invasion of the Mono River by sand. Faced with this alarming situation, the French Fund for the Global Environment (FFEM) initiated a project “Soft solutions and monitoring of coastal risks in Benin” with a view to restoring the dune system in the sector of the mouth of the Mono River in the commune of Grand Popo to safeguard the ecological and ecosystem role of this area. The objective of this work is to consolidate and sustain the advances in coastal observation mechanisms, at the regional and national levels, to influence public policies on the issues of coastal risks and the management of coastal areas but also to initiate a series of field, pilot activities for the implementation of soft solutions for coastal protection. The results obtained concerning the installation of typhavelles and Epis Maltais Savard (SEMS) for fixing mobile dunes at the Grand Popo wetland are very encouraging for the preservation of this site of international importance.
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Skrzyński, M., R. Dańko, and J. Kamińska. "Reclamation of Mixtures of Spent Sands of Inorganic and Organic Type." Archives of Foundry Engineering 13, no. 4 (2013): 93–96. http://dx.doi.org/10.2478/afe-2013-0089.
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Abstract The results of investigations of the reclamation of spent moulding and core sands, originated from one of the Polish foundry plants, are presented in the paper. Four mixtures consisting of two types of spent sands (spent moulding sand and spent core sand) were subjected to the regeneration process. Each tested mixture consisted of an inorganic type spent moulding sand and of an organic type spent core sand. Proportions of mutual fractions of spent moulding and core sands in mixtures was 70%-30% and was representative for the waste sands from the foundry, from which these sands originated.
Dissertations / Theses on the topic "Sand cord"
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Heydari, Farhad. "Mechanisms of sand flow and compaction in core-blowing." Thesis, University of Warwick, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357857.
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Bohlin, Ulrika. "Comparing Cork Filters to Conventional Sand Filters : A Pilot Study of Process Water Treatment." Thesis, Uppsala universitet, Avdelningen för systemteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-161813.
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Process water is used for cooling and for transporting material in all kinds of industries. To clean the water for reuse, various types of filters can be used. Many conventional process water treatment plants incorporate sand filters, which readily clean the water from suspended matters. However, at some circumstances the sand filters do not remove high enough concentrations of metals. This master thesis compares the water treatment abilities of activated cork, produced by Spikes & Cogs AB, to those of the sand filters used at steel making company Ovako Hofors AB in Hofors. As an on-site pilot study, the thesis investigates the cleaning capacity of three types of activated cork filters: Fats, Oils and Solvents (FOSS) filter, Fast Acting Digesting Enzymes (FADE) filter, and Metal Adsorption and Concentration (MAAC) filter. The cork filters were compared to the sand filters during normal operation and, because of previous problems with the stability of the sand filter performance, during stress tests. The results show that the cleaning capacity of the sand filters is higher than the cleaning capacity of the cork filters at normal operation. At the conditions of the stress tests, at which the sand filters do not function, the cleaning capacity of the cork filters was somewhat lowered but was still well within acceptable limits. An important result from the experiments is that the cork filters neutralize the pH. The sand filters are sensitive to changes in the pH, meaning that the cork filters could function as a buffering unit prior to the sand filters.
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Edgington, Ryan H. "Lines in the Sand: An Environmental History of Cold War New Mexico." Diss., Temple University Libraries, 2008. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/10613.
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History<br>Ph.D.<br>This dissertation explores the complex interactions between the Cold War military-scientific apparatus, the idea of a culture of the Cold War, and the desert environment of the Tularosa Basin in south-central New Mexico. During and after World War II, the War Department and then the Department of Defense established several military reserves in the region. The massive White Sands Missile Range (at 3,200 square miles the largest military reserve in North America and larger than Rhode Island and Delaware combined) and other military attachés would increasingly define the culture and economy of the Tularosa Basin. Historians have cast places such as White Sands Missile Range as cratered wastelands. Yet the missile range and surrounding military reserves became a contested landscape that centered on the viability of the nonhuman natural world. Diverse communities sought to find their place in a Cold War society and in the process redefined the value of a militarized landscape. Undeniably, missile technology had a profound impact on south-central New Mexico and thus acts as a central theme in the region's postwar history. However, in the years after 1945, environmentalists, wildlife officials, tourists, and displaced ranchers, amongst many others, continued to find new fangled meanings and unexpected uses for the militarized desert environment of south-central New Mexico. The Tularosa Basin was not merely a destroyed landscape. The design and sheer size of the missile range compelled local, national, and transnational voices to not just make sense of the economic implications of the missile range and surrounding military sites, but to rethink its cultural and environmental values in a changing Cold War society. It was a former home to ranchers still tied to the land through lease and suspension agreements. New Mexico Department of Game and Fish personnel cast the site as perfect for experimentation with exotic big game. Environmentalists and wildlife biologists saw the site as ideal for the reintroduction of the Mexican wolf. Tourists came to know the landscape through the simple obelisk at the Trinity Site. While missiles cratered the desert floor, the military bureaucracy did not hold absolute power over the complex interactions between cultures, economies, and the nonhuman natural environment on the postwar Tularosa Basin.<br>Temple University--Theses
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Cantó, i. Navés Elisabet. "Diferències fenotípiques i funcionals dels limfócits CD4+ de sang de cordó umbilical i sang perifèrica d'adult." Doctoral thesis, Universitat de Barcelona, 2003. http://hdl.handle.net/10803/3015.
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Des de l'any 1989 en que es va realitzar el primer trasplantament de cèl·lules hematopoiètiques procedents de la sang de cordó umbilical (SCU) a un pacient amb anèmia de Falconi, ha anat creixent l'interès per les característiques immunològiques de la sang de cordó umbilical. Un dels principals avantatges que presenta la SCU és la baixa incidència en la malaltia de l'injert contra l'hoste (GVHD) que es desencadena després del trasplantament entre pacients no emparentats. Fins el moment tots els treballs han demostrat que els limfòcits T de SCU presenten un fenotip CD45RA+ que indicaria en un principi la manca d'exposició prèvia a antígens i aquesta característica ha comportat que es considerés als limfòcits <i>naive</i> de SCU com immunològicament immadurs i amb una resposta peculiar enfront a diversos estímuls. L'ús de diferents condicions experimentals i sistemes d'activació han donat lloc a resultats no comparables i a vegades fins i tot contradictoris. Per una banda, l'ús de tècniques de separació que comportin la pèrdua sel·lectiva de poblacions cel·lulars o produeixin pertorbacions funcionals, i per l'altra la utilització de diversos agents per activar les cèl·lules que intervenen a diferents nivells de la cascada de senyalització, han donat lloc a resultats difícils d'interpretar. L'objectiu general d'aquest treball ha estat de caracteritzar la població majoritària CD4+CD45RA+ de SCU utilitzant un anticòs monoclonal anti-CD3 humà (OKT3), que permet una activació de tots els limfòcits independentment de la seva especificitat.<br/>Per abordar aquest objectiu, es va obtenir la població majoritària CD4+CD45RA+ de la sang de cordó umbilical i de sang perifèrica d'adult, utilitzant una selecció negativa, que consistia en l'obtenció dels limfòcits CD3+ a partir de les cèl·lules mononuclears obtingudes per gradient de Ficoll, i una segona selecció negativa a partir dels limfòcits CD3+ per poder obtenir la població CD4+CD45RA+ purificada. El grau de purificació es va determinar per citometria de flux.<br/>L'estudi fenotípic i funcional dels limfòcits CD4+CD45RA+ de sang de cordó umbilical va demostrar que aquesta població limfocitària presentava característiques que la diferenciava de la població CD4+CD45RA+ de la sang perifèrica d'adult. Així s'observà, que els limfòcits <i>naive</i> de SCU presentaven una major tendència a entrar en apoptosi espontània comparat amb la SPA, i que aquesta mort podia ser en part revertida per la presència d'interleuquina 2 (IL2). Una activació via TCR/CD3 amb una sola senyal anti-CD3 portà als limfòcits <i>naive</i> de SCU a activar-se, dividir-se i finalment a morir per apoptosi. Aquesta activació anava acompanyada d'una fosforilació diferencial en Tyr de proteïnes implicades en els primers processos de la cascada de senyalització via TCR, transformació blàstica, expressió de marcadors d'activació en superfície i divisió cel·lular. La coestimulació via CD28 feia que els dos tipus cel·lulars assolissin uns graus d'activació similars, excepte en l'coexpressió de CD45RO que només s'observava amb la SCU.<br/>No sabem si la resposta de les cèl·lules naive observada <i>in vitro</i> pot ser sobrepassada in vivo per altres factors i tampoc coneixem el paper de les cèl·lules de SCU en l'expansió perifèrica després del trasplantament. Després del trasplantament amb cèl·lules de SCU, la primera onada de reconstitució de cèl·lules T s'origina per les cèl·lules T donants madures presents en l'injert. L'estimulació de les cèl·lules de SCU a través del receptor per l'antigen sense coestimulació podria induir un estímul toleritzant mitjançant l'activació subòptima i la posterior eliminació d'una gran part de les cèl·lules activades. En aquest cas, l'apoptosi és possiblement sel·lectiva per cèl·lules reactives donants, fenomen que es contempla com la base de la tolerància en el trasplantament i que podria explicar l'aparent reducció del GVHD en els individus trasplantats amb SCU.
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Klein-Paste, Alex. "Runway Operability under Cold Weather Conditions. Tire-pavement friction creation by sand particles on iced pavements, and non-contacting detection of sand particles on pavements." Doctoral thesis, Norwegian University of Science and Technology, Department of Civil and Transport Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2062.
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<p>Airports that operate under cold weather conditions face major challenges in ensuring that runways, taxiways and aprons provide sufficient tire-pavement friction to the operating aircraft. This thesis is motivated by two practical problems: (1) maintaining or improving the pavement surface conditions in an, for airline companies, acceptable state and (2) accurately reporting the actual surface conditions to the relevant actors (pilots, air traffic control, winter maintenance services). The primary objective of this thesis is to broaden the general knowledge base of these problems. The work can be divided into a practical, a fundamental, and an applied part of the thesis.</p><p>The practical part includes a field study on how runway surface conditions change in time and the consequences for runway operability. Different situations were documented where the runway surface conditions changed due to snow fall, sand displacement by aircraft, ice deposition, snow compaction, and melting of the contamination layer. These cases highlighted two weaknesses in the current reporting system: (1) the constrained inspection frequency of the runway surface and (2) the limited possibilities to monitor the surface conditions while the runway is open for air traffic. The practical part also included field studies on a new sanding method, based on pre-wetting the sand with hot water. Practical experiences from maintenance personnel were collected, runway surface conditions were documented, and comments from pilots on the reported conditions were investigated. The method provides a solution for the problem that loose sand can be displaced or blown off the runway by the engine thrust of operating aircraft. In addition, the study highlighted some potential negative effects related to the sanding method. The high friction values that are typically measured on surfaces treated with warm pre-wetted sand can create a too optimistic picture of the prevailing conditions for aircrafts. Cases are documented where pilots faced worse conditions than they expected from the provided friction numbers. In 66 % of the cases there were clear indications available that the situation was not as good as suggested by the friction measurements. Another aspect is the risk of Foreign Object Damage (FOD). Maintenance personnel pointed out the importance of proper pavement cleaning prior to the sand application.</p><p>The fundamental part of the thesis focuses on the role of sand in the creation of tirepavement friction on iced surfaces. The presence of sand particles changes the interaction between the tire, the pavement, the contamination layer, and the atmosphere in which the interaction takes place. Hence, it changes the way friction is created. The interactions were studied on a macroscopic scale by observing tire tracks on sanded, iced runways and by aircraft braking experiments on ice treated with loose and warm, pre-wetted sand. These observations showed that loose sand particles, ones trapped between the tire and the ice, can slide together with the rubber tread and plough into the ice layer. Loose sand particles can pile-up in front of, and under, locked tires (full skid). Such tire lock-ups can occur, even though when aircraft are equipped with anti-skid braking systems because these systems become disabled below a certain threshold speed (ranging between 30 and 45 km/h, depending on the aircraft type). On freeze bonded sand (produced by the warm, pre-wetted sanding method), friction can be provided by both loose particles that plough into the ice and by particles that stay fixed to the ice and force the tire tread to deform.</p><p>The sand-ice and rubber-ice interactions were also studied on a microscopic scale by etching and replicating the ice surface. These observations revealed that the sliding friction process involved ice deformation in both cases. During rubber-ice sliding friction, the original crystal structure of the ice remained intact during the interaction. However, small scale ice deformation was evident by the formation of dislocations, aligned in rows along the sliding direction, and by the formation of small scale ploughing tracks. In the case of sand-ice interaction, the ploughing of sand particles was accompanied with the formation of cells within the original crystal structure of the ice. This re-crystallization was observed both in the laboratory and in the field. The rubber-ice and sand-ice sliding friction mechanisms were studied quantitatively by using a British Pendulum Tester in a cold laboratory experiment. It was found that the observed variability in friction measurements was significantly larger than the uncertainties introduced by the instrument itself. The variability may be caused by poorly controllable/reproducible, microscopic or nanoscopic surface properties of the ice and rubber. Rubber-ice interaction resulted in appreciable friction coefficients (0.5 ≥ μ ≥ 0.2) at ice temperatures below -5°C. However, it dropped significantly (down to μ = 0.05) over the whole tested temperature range to by the presence of little snow on the ice (less than 1 mm). It demonstrated that friction provided by rubber-ice interaction is very vulnerable to snow contamination. In contrast, sand-ice friction measurements did not show the dramatic drop in friction by the same amount of snow. Hence, the ploughing of relatively large sand particles provided a more robust mechanism of friction, compared to rubber-ice friction.</p><p>The applied part of the thesis comprises an exploratory study on a non-contacting measurement principle to quantify the amount and distribution of sand particles on a pavement. A static laboratory arrangement was build where sanded pavements were illuminated by a visible laser light source (wavelength: 635 nm) at different angles of incidence. The radiance from the illuminated area was recorded with a digital camera at different angles. The test matrix included dry and iced pavements and different sand application rates. A correlation between the total radiance and sand application rate was only found when there was negligible radiance from the pavement in the scene. The sand detection therefore required a distinction between radiance originating from the sand and the radiance originating from the pavement. However, due to the similarities in optical properties of the sand and the aggregates in the pavement (both originate from crushed rock) and the transparency of ice in the visible range, it seemed unlikely that the distinction can be made on the basis of radiance intensity. An alternative approach was investigated, based on triangulation. Image analysis techniques were used to define a region of interest where the radiance only originates from the sand. Within this region, individual sand particles can be identified and counted. The principle was developed theoretically for flat surfaces and adapted for application on rough surfaces of unknown topography. It was tested on a selected group of images, taken under favourable incidence and camera angles. The algorithm placed the region of interest reasonably well in all analyzed images, resulting in a rather conservative input in the subsequent analyses. The sand detection algorithm had a success rate between 63 and 100 %, depending on the surface contamination. The errors were mainly caused by not detecting particles that were located in the lower parts of the surface topography. Only few mistakes were made by incorrectly identifying particles. Hence, the number of detected particles was a conservative estimate of the actual number of particles located in the region.</p>
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Sierer, Rachel. "The zooarchaeology of two pony express stations in Central Nevada Sand Springs and Cold Springs /." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1460778.
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Rudert, Alexander. "Experimentelle und Numerische Untersuchung des Kernformstofffließens." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2010. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-27163.
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Die Arbeit befasst sich mit der Untersuchung des Kernformstofffließens als nichtnewtonsche Fluidströmung. Dazu werden verschiedene Formgrundstoffe und Kernformstoffe rheologisch untersucht. Als Bindersysteme kommen PUR Coldbox und Wasserglas zum Einsatz. Für diese Untersuchungen wird ein eigens für diesen Zweck entwickeltes Messgerät verwendet. Die gewonnenen Daten werden in ein numerisches Modell implementiert, welches mit den Methoden der numerischen Strömungsmechanik den Kernschießvorgang abbildet. Dabei kommt der Open Source CFD Code OpenFOAM zum Einsatz. Der Kernschießvorgang wird mit verschiedenen Kernkastengeometrien numerisch und experimentell untersucht und die Ergebnisse verglichen.
Die Ergebnisse der rheologischen Untersuchungen zeigen deutlich den Einfluss der Beschaffenheit des Formgrundstoffes und des Bindersystems auf die Fließfähigkeit des Kernformstoffes. Der Vergleich zwischen Experiment und Simulation zeigt gute Übereinstimmung. Das formulierte Modell gibt die Möglichkeit, Probleme in der Kernqualität vorherzusagen.
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Sanders, Dwayne Paul. "Corn Stover Removal Effects on Irrigated Sandy Outwash Soils in North Dakota." Thesis, North Dakota State University, 2015. https://hdl.handle.net/10365/27845.
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Recent interest in utilizing corn (Zea Mays L.) stover for cellulosic ethanol and supplements for distillers' grain in livestock rations has increased corn stover demand. A study was established to evaluate corn stover removal on selected soil properties in irrigated sandy outwash soils under no-tillage management including continuous corn and corn-soybean (glycine max) rotations. For continuous corn, increasing stover removal rates (0 to 100%) increased the wind erodible soil fraction (25.4 to 36.6%), decreased the field-moist water stable soil aggregates (58.78 to 48.3%) and water infiltration rates (22.4 to 8.6 cm/hr). Water infiltration rates decreased in the corn phase of the corn-soybean rotation (16.8 to 10.8 cm/hr) and air-dry water stable aggregates decreased in the soybean phase of the corn soybean rotation (88.1% to 77.7%) for 100% removal when compared to 0% removal. Longer-term evaluation of stover removal is needed to fully evaluate stover removal effects on soil properties.<br>North Dakota Corn Council
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Almaghariz, Eyad S. "Determining When to Use 3D Sand Printing: Quantifying the Role of Complexity." Youngstown State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1433778181.
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Sagintayev, Zhanay. "Relationship between 20th century dune migration and wetland formation at Cape Cod National Seashore, Massachusetts." Virtual Press, 2006. http://liblink.bsu.edu/uhtbin/catkey/1339460.
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Outer Cape Cod (Massachusetts) is dominated by active and stabilizing parabolic and transverse dunes interspersed with numerous inter-dune wetlands. Dune migration has been significantly affected by human activities; conversely, current dune movements are affecting local populations. The objective of the reported research was to assess, using remote sensing and geographic information systems (GIS) technologies, migration of the Cape Cod dunes and the effect of dune movement on distribution of associated wetlands. Aerial photographs from 1938 through 2003 were analyzed to track individual dune movements and subsequent wetland propagation and expansion. Absolute dune movement rates during this period were computed, with a plot of dune movement as a cumulative function. One sub-problem of this study was to quantify `white' areas of active moving sand and `dark' areas of vegetation, in order to quantify changes in vegetative cover with wetland propagation and, conversely, vegetative disappearance with dune movement. Attempts were made to correlate the Palmer Drought Severity Index (PDSI) with dune migration. Based on review of aerial photographs, parabolic dunes have migrated 150 to 250 m since 1938, with 60% of the movement occurring between 1938 and 1977. The relation between absolute parabolic dune migration and corresponding PDSI is approximately logarithmic. Maximum dune migration is associated with PDSI values lower than -2 and reflects moderate drought conditions. Wetlands consistently trailed the dunes, and the distance of wetland movement was related to dune movement distances. Wetland migration was particularly marked from the 1950s to the 1980s. Based on review of georeferenced aerial photographs, it is concluded that marked stabilization of Cape Cod dunes occurred in the 1980s and 1990s, with renewed movement in the 21st Century. This study provides a practical application for assessment of dune migration and vegetative transformations over time using remote sensing and GIS technologies.<br>Department of Natural Resources and Environmental Management
Books on the topic "Sand cord"
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Society of Petroleum Engineers (U.S.), ed. Shaly sand analysis. 2nd ed. Society of Petroleum Engineers, 2003.
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Heydari, Farhad. Mechanisms of sand flow and compaction in core-blowing. typescript, 1990.
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Dijkmans, Jos W. A. Aspects of geomorphology and thermoluminescence dating of cold-climate eolian sands. Koninklijk Nederlands Aardrijkskundig Genootschap, 1990.
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1941-, Young Allen, and Brender à Brandis G, eds. More than sand and sea: Images of Cape Cod. Millers River Pub. Co., 1985.
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Holtzer, Mariusz, and Angelika Kmita. Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9.
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network), TechTV (Television, ed. TechTV's cutting the cord: A wireless consumer guide. Que, 2002.
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Alberta. Energy Resources Conservation Board. Commercial oil sands project and water disposal scheme cold lake oil sands deposit primrose sector. Energy Resources Conservation Board, 1985.
Find full textBook chapters on the topic "Sand cord"
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Holtzer, Mariusz, and Angelika Kmita. "Green Sands." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_10.
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Vandeviver, Nicolas. "Cold Reading." In Edward Said and the Authority of Literary Criticism. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-27351-4_2.
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Holtzer, Mariusz, and Angelika Kmita. "Sodium Silicate Molding Sands." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_9.
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Holtzer, Mariusz, and Angelika Kmita. "Protective Coatings for Mold and Core Sands." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_12.
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Holtzer, Mariusz, and Angelika Kmita. "Cold-Setting Processes (No-Bake)." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_6.
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Holtzer, Mariusz, and Angelika Kmita. "Gas-Hardened Processes (Cold-Box)." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_7.
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Holtzer, Mariusz, and Angelika Kmita. "Other Molding and Core Sands with Inorganic Binders." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_11.
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Holtzer, Mariusz, and Angelika Kmita. "Division of the Molding and Core Sands: Criteria." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_5.
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Holtzer, Mariusz, and Angelika Kmita. "Alternative Methods Using in Mold and Core Technologies." In Mold and Core Sands in Metalcasting: Chemistry and Ecology. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53210-9_13.
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Zhu, Ying-bin, Huai-wen Li, Hong-yan Liu, et al. "Research and Application of Cold Production Sand Control Technology in Heavy Oil Sand Production Well of D Oilfield in Bohai Bay." In Proceedings of the International Field Exploration and Development Conference 2021. Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-2149-0_329.
Full textConference papers on the topic "Sand cord"
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Zahedi, Peyman, Ronald E. Vieira, Siamack A. Shirazi, and Brenton S. McLaury. "Liquid Film Thickness and Erosion of Elbows in Gas-Liquid Annular Flow." In CORROSION 2016. NACE International, 2016. https://doi.org/10.5006/c2016-07711.
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Abstract Pipe fittings such as elbows and tees are often used in oil and gas production systems and are vulnerable to erosion damage when sand production is anticipated. Annular flow and low liquid loading flows are mostly observed in multiphase gas production pipelines. Sand erosion of elbows and tees in annular flow is complicated by separation of phases including sand, droplet and sand particle entrainment in the gas core and deposition of entrained droplets and sand to the liquid film. Additionally, experiments have shown that average liquid film thickness along the outer bend of the elbow is lower than that for upward vertical flow in straight sections of pipe. The liquid film thickness in the bend can significantly affect erosion as particles that are entrained in the gas core have to penetrate through the liquid film to impact the pipe wall. In order to accurately predict erosion magnitude within pipe bends, prediction of liquid film thickness in bends is important. In this study, experimental data and CFD calculations are being used to predict annular flow characteristics and liquid film thickness. The simulation results of liquid film thickness trends are in reasonable agreement with the experimental data available in the literature. The use of predicted liquid film thicknesses in high gas superficial velocities and low liquid rates allows more accurate prediction of erosion in elbows. A comparison of predicted erosion magnitude with previously developed models for predicting erosion in annular flows and experimental data indicates that the new modifications improve the predicted erosion data.
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Bakhtiyarov, Sayavur I., and Ruel A. Overfelt. "Experimental Study of Multiphase Flow in Cold Box Core Process." In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-2709.
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Abstract The results of experimental study of pressure variations inside core box during resin bonded sand filling process are reported. The test core specimens were produced using Laempe® Test Specimen Curing Machine L 1. A special pressure measurement system was designed and built with safety and portability requirements of the foundry environment. Special experiments were conducted to establish the effect of sand deposition on vent permeability.
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de Borst, Karin, Chee Phuat Tan, M. Faizzudin Mat Piah, and Jeroen Groenenboom. "First-Time Insights into Hydraulic Fracturing of Unconsolidated Sands from Novel Laboratory Experiments with in-situ CT-Scanning." In International Petroleum Technology Conference. IPTC, 2021. http://dx.doi.org/10.2523/iptc-21198-ms.
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Abstract Waterflooding in unconsolidated sands has been observed to frequently result in injectivity decline of injectors when operated under ‘fractured’ conditions, resulting in reduction of waterflooding value creation and potential premature injector failure. Optimization of injector design and operation is currently limited by an insufficient understanding of the mechanics of ‘fracture’ and its associated mechanisms in unconsolidated sands, and the lack of adequate quantitative tools to predict injection performance. Utilizing in-situ CT scanning during large-scale laboratory injection experiments delivered novel insights into generation, closure and re-opening of ‘fractures’ in sand packs built from synthetic sands and highly unconsolidated downhole core material. Cavity formation was identified as main ‘fracturing’ mechanism. The cavities opened at injection pressures exceeding the confining stress and subsequently enlarged against a very low cohesive strength for the downhole core sands. This suggests material fluidization rather than shear failure as the immediate cavity initiation mechanism. Injectivity was found to be controlled by the interplay of fines transportation away from the injection region, resulting in injectivity increase, and the permanent compaction of the sand around the cavity, resulting in injectivity decrease. These first-time insights challenge the current understanding of matrix vs ‘fractured’ injection in unconsolidated sand reservoirs and highlight the role of sand fluidization and cavity formation. Furthermore, the injectivity behaviour is dependent on the combined effects of the sand material, the presence of fines, and the injection flow regime. The knowledge of the sand destabilization and mobilization processes enable design and operation optimizationof water injectors with implications on sand control strategies and remediation measures.
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Isdiken, Batur, Tanmoy Dutta, Ugur Yüce, and Mert Kiliç. "Integration of RCA and SCAL with Image Logs Leads to a Unique High Resolution Technique to Evaluate Laminated Clastic Reservoirs of Black Sea, Turkey." In SPE Caspian Technical Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/217521-ms.
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Abstract Deep water gas reservoirs in the Western Black Sea consist of highly laminated heterogeneous and complex sand/shale sequences. A petrophysical volumetric model was created by combining the triaxial induction resistivity data with the Thomas-Stieber (1975) sand-shale volumetric model to better evaluate low-resistivity pay zones in highly laminated shaly sand sequences. Although the results from this method are volumetrically almost correct, they are quite insufficient to deal with the distinctions between finely laminated sand, silt and shale. In order to calculate volumetric petrophysical parameters, such as porosity and water saturation, which are linearly or non-linearly derived from the sand/shale fraction of the rock volume, accurate measurement of laminar shale volume in shaly sand sequences is an essential first step. Even though GIIP does not change much, the volumetric method presents a particular challenge in terms of continuity of gas bearing layers when there is water located in both above and below the gas-bearing sands. High-resolution wireline image tools with a vertical resolution of 0.5 cm can capture bed thicknesses and boundaries of these sand layers, enabling the determination of the net to gross sand ratio. However, imaging technologies by themselves are unable to determine precise porosity and water saturation. By statistically evaluating extensive volumes of core data (RCA and SCAL) and image logs, a new high-resolution methodology offers a simple and innovative method to compute porosity and saturation. A partially cored reservoir section example is used to demonstrate the entire technique. This approach does not require standard log deconvolution. The uncertainty has been understood after comparing the results between the volumetric model and high-resolution model. By using the methods described in this paper, it is possible to position the perforation interval more precisely and reduce uncertainty for volumetric petrophysical calculations in complex highly laminated clastic reservoirs. The results show that low resistive laminated clastic reservoirs can be extremely productive, showing reservoir quality comparable to that of productive thick sands.
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Bakhtiyarov, Sayavur, Ruel A. Overfelt, Amit Suryawanshi, and Johnathon Capps. "Numerical Simulations and Experimental Study of Hot Core Distortion Phenomenon in Aluminum Casting." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56510.
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This paper presents the results of experimental and numerical studies of hot distortion phenomenon in the phenolic urethane cold box systems. Dual Pushrod Dilatometer has been used to measure a thermal expansion/contraction of phenolic urethane cold box sand core specimens at temperature range from 25° C to 800° C. The high temperature tensile tests showed that the tensile strength of the phenolic urethane cold box silica sand cores is significantly affected by the bench life, temperature and binders level. High temperature hot distortion furnace tests on cylindrical cores showed that some aluminum coatings increase the temperature limit when distortion starts, but can’t prevent it. The hot distortion test aluminum castings showed that regardless of the application of coating, the type of coating, and anti-veining additives, all cores (silica sand) with density less than the density of the molten metal (aluminum alloy) were significantly distorted. Numerical simulations of the liquid metal flow around the cylindrical sand core and analysis of dynamic forces acting on the core during fill process showed that a buoyancy force is the major contributor to the hot distortion. It is concluded that the one of the solutions in preventing the hot distortion of sand cores is increasing their weigh, which will balance the buoyancy force and will bring the resultant force to the minimum. The hot distortion test castings using zircon sand cores (both coated and non-coated) with density almost equal to the density of the molten aluminum proved our predictions, and hot distortion has been prevented.
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Anschutz, D., M. McGill, S. Fleming, C. Landis, and T. Cage. "Turbidity in Frac Sand from Proximity Mines in the Permian Basin: Is it Detrimental to the Fracture System?" In SPE Hydraulic Fracturing Technology Conference and Exhibition. SPE, 2025. https://doi.org/10.2118/223580-ms.
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Abstract Regional and proximity sand mines dominate the landscape in the Permian Basin of West Texas and Southeast New Mexico. Vast Cenozoic Monahans Formation sands offer critical, long-term sustainable proppant supply, specifically in-basin sand, for Permian Basin unconventional exploration and development. The industry is investing in a wide range of processing methods to develop the dune fields of West Texas. The regional variation of the dune fields and stratigraphy introduce complexities that require adaptation of ore processing to improve the quality of the final product. The focus of this study is to show how the concentration and type of contaminates in the sand, indicated by turbidity measurements, could alter the performance as a proppant system. Turbidity is produced by multiple mineral contaminants (silts and clays) in the otherwise quartzose sand that are not efficiently removed during processing. This paper classifies this suspended material into three groups: silicates (quartz, feldspar, etc.), clay (phyllosilicates), and caliche (calcium carbonate). This study focuses on the correlation between the composition and content of these admixtures and the hydraulic conductivity of the stimulated reservoir. This study presents the results of an integrated effort to characterize compositional aspects of the Monahans sands with respect to their conductivity performance. Controlled laboratory experiments, including turbidity measurements, conductivity, and X-ray diffraction (XRD), are conducted on sand samples from multiple locations in the Permian Basin. The objective is to understand the effect of contaminants on the performance of the sand without the formation core interface. Field samples evaluated varied in turbidity levels of less than 250 Nephelometric Turbidity Unit (NTU) to greater than 2500 NTU. Northern white sand (NWS), with similar sizing, was used to compare additional physical features between sands, i.e., roundness, sphericity, etc. Ultimately, all findings were integrated with mineralogical analysis to assess the impact of turbidity and specific minerals, such as quartz, feldspar, and various clay minerals, on conductivity. The results of this work indicate that 1) in-basin sands yield highly variable and generally higher turbidity than mid-continent sands, 2) both the level and mineral composition of the turbidity itself can significantly impact the permeability and conductivity of a stimulated resource, Finally, the differences in the physical features between regional sands and NWS may require additional investigation of API Standard testing methodology. While the value of the in-basin Monahans Sands to the future of Permian Basin unconventional resource development is undisputed, oilfield operators and industrial sand producers can unlock additional value by adapting mineral processing and treatments to the specific geology of these deposits. Versatile, in-process, and down-hole solutions are available to enhance the performance of fracturing fluids while addressing the inherent variability of these sand deposits.
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Tolioe, William Amelio, Linda Hanalim, Joely Bt A Ghafar, and Thanapala Singam Murugesu. "Integrated Advance Petrophysical Evaluation for Heterolithic Clastics Reservoir Characterization Optimization in Malay Basin." In Offshore Technology Conference Asia. OTC, 2022. http://dx.doi.org/10.4043/31452-ms.
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Abstract In an oil producing S-field within Malay basin, the existence of heterolithic and thinly laminated reservoirs are common. Standard resolution logging tools are incapable to separate inter-bedded sand-shale layers due to their low vertical resolutions and the conventional petrophysical workflow was not robust enough in capturing the actual properties of the laminated sand shale (LSS) reservoirs in S-field. As a result, the estimated permeability did not match the core permeability and required a significantly high multipliers in the dynamic model and the calculated saturation failed to match the Dean-Stark saturation. This paper explains the limitation of the conventional analysis in LSS reservoir and highlights the use of PETRONAS Thin Bed Analysis (TBA) module to estimate the actual reservoir properties in S-field. The case study in this paper shows the best practice to construct the robust fieldwide evaluation of reservoir properties, integrating core to production data and advance logs information, to determine reservoir properties. In LSS reservoirs, the conventional petrophysics outputs are often pessimistic compared to core data. Reservoir Enhancement Modeling and Reservoir Fraction Modeling (REM-RFM) is an in-house PETRONAS TBA methodology for evaluating LSS reservoirs. REM-RFM workflow is designed to obtain the net sand fraction and the actual reservoir properties to describe the reservoirs storage and flow capacity. Sand-shale lamination was quantified by digital core analysis, core UV light binning against the borehole image logs. The triaxial resistivity logs were used as inputs for the Thomas-Stieber method to determine the net sand fraction and the hydrocarbon saturation. Nuclear Magnetic Resonance (NMR) data was also incorporated to confirm the hydrocarbon pore volume on well level. The REM-RFM workflow resulted in the improved reservoir properties compared to the conventional evaluation and were better matched to the core. In the laminated sands, the enhanced shale volume was comparable to the sand streaks seen in UV fluorescence core photo and image logs data, as well the enhanced porosity and permeability were matching well with the core data. Moreover, the water saturation was matching to the saturation from dean-stark core analysis result, comparable to saturation height function model and NMR data, and REM-RFM output were comparable to Thomas-Stieber results. Once the REM-RFM was calibrated in the key wells, the parameters were then applied to the whole field. The in-house REM-RFM module discussed in this paper is an excellent addition to other industry methodologies. This module is basically a continuation of the innovative effort to characterize the conventional clastic reservoirs model performed earlier. It has been proven by applying robust evaluation, the conventional outputs are significantly improved that led to the optimizes the obvious volume of hydrocarbon estimated. In addition to that, the results can be used for reducing the risks in monetizing the opportunities from the heterolithics and laminated sands.
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Amer, H., K. Sheng, R. Okuno, et al. "A Study of DME-Steam Co-Injection Using a Large-Scale Physical Model." In SPE Canadian Energy Technology Conference and Exhibition. SPE, 2024. http://dx.doi.org/10.2118/218077-ms.
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Abstract Dimethyl ether (DME) as a water-soluble solvent has been studied as a potential additive to steam for improving the energy efficiency of steam-assisted gravity drainage (SAGD). The main objective of this research was to study in-situ flow characteristics and energy efficiency of DME-SAGD using a large-scale physical model. Results from DME-SAGD were compared with the control experiment of SAGD with no solvent injection using the same experimental setup. The main novelty of this research lies in the experimental data that demonstrated enhanced bitumen drainage by DME-SAGD in comparison to SAGD. The experiment was conducted in a cylindrical pressure vessel with a diameter of 0.425 m and a length of 1.22 m, which contained a sand pack with a porosity of 0.34 and a permeability of 5.0 D. The DME-SAGD experiment used a DME concentration of 10 mol% and a steam co-injection rate of 27.6 cm3/min [cold-water equivalent (CWE)] at 3000 kPa. Temperature distributions within the sand pack, along with injection and production histories, were recorded during the experiment. Subsequently, numerical simulations were performed to history-match the experimental data, and the calibrated simulation model was used to analyze details of compositional flow characteristics. Results showed that the 10 mol% DME-SAGD experiment yielded a recovery factor of 92.7% in 4.2 days, and the SAGD experiment yielded a recovery factor of 68.6% in 6.0 days, for both of which the first 2 days were the preheating and the steam-only injection (SAGD) stages. The peak rate of bitumen production was 43.8 mL/min in the DME-SAGD experiment, which was more than twice greater than the peak rates observed in the SAGD experiment. The substantially increased rate of bitumen production resulted in a cumulative steam-to-oil ratio in DME-SAGD that was less than half of that in SAGD. Analysis of experimental results indicated that the solubility of DME in the aqueous and oleic phases caused different flow characteristics between DME-SAGD and SAGD. For example, the oleic and aqueous phases were more uniformly distributed in the sand pack in the former. Simulations indicated that DME-SAGD had a uniform distribution of greater grid-scale Bond numbers and increased oleic-phase mobilities in comparison to SAGD.
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Samuel, Elvy Jose, Mohd Shah Redza Hanif, Muhd Syaiful Azman Mustapa, et al. "Advance Nuclear Magnetic Resonance and Image Logs Application for Predicting Particle Sand Distribution." In IADC/SPE Asia Pacific Drilling Technology Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/209912-ms.
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Abstract The complexities of designing an effective sand control for unconsolidated gas reservoirs in a deepwater environment is exacerbated when the targeted formation sands are characterized by particle size distributions with poorly sorted and non uniform coeficients, and high fine concentrations. Managing these intricacies requires comprehensive sand retention studies developed to ascertain the effectiveness of the sand control performance of gravel and screen gauge opening combinations in the presence of selected formation sand ratios. To build a representative testing program, actual core samples from the targeted studied zones are desirable. However, for economical, technical or logistic contrains the availability of these cores is not always feasible. This paper covers a workflow to determine a synthetic Particle Size Distribution (PSD) of a targeted well in a development block where no core data is available. The data feeding the workflow is derived from wireline bore hole imagers and Non-Magnetic Resonance (NMR) logs obtained from six wells drilled in the exploration phase of the studied gas block. Results are calibrated with localized PSD from available side wall cores. Furthermore, data obtained from the process is used to interrogate sand retention testing Mastercurves built with formation samples from one of the fields in the studied block (Field I). The interrogation process takes the synthetic PSD from the targeted well and creates normalized formation testing ratios which are then compared to the results documented on the sand retention Mastercurves. This paper is intends to discuss the worklflow and results of its field application.
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Yalamas, T., J. F. Nauroy, E. Bemer, L. Dormieux, and D. Garnier. "Sand Erosion in Cold Heavy-Oil Production." In SPE International Thermal Operations and Heavy Oil Symposium and Western Regional Meeting. Society of Petroleum Engineers, 2004. http://dx.doi.org/10.2118/86949-ms.
Full textReports on the topic "Sand cord"
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Prof. John J. Lannutti and Prof. Carroll E. Mobley. Improvements in Sand Mold/Core Technology: Effects on Casting Finish. Office of Scientific and Technical Information (OSTI), 2005. http://dx.doi.org/10.2172/841468.
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Lawson, Vincent. Corn Response to Sulfur Fertilization when Grown on Irrigated Sandy Soil. Iowa State University, Digital Repository, 2014. http://dx.doi.org/10.31274/farmprogressreports-180814-1244.
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Mallarino, Antonio, Pablo Barbieri, Ryan Oltmans, Joshua Enderson, and Vine Lawson. Corn and Soybean Yield Response to Micronutrients in an Iowa Sandy Soil. Iowa State University, Digital Repository, 2015. http://dx.doi.org/10.31274/farmprogressreports-180814-2631.
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Lawson, Vince. Evaluating Nitrogen Stabilizers for More Efficient Nitrogen Use when Growing Corn on Sandy Soil. Iowa State University, Digital Repository, 2017. http://dx.doi.org/10.31274/farmprogressreports-180814-1618.
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Borrelli, M., E. Shumchenia, C. G. Kennedy, et al. Submerged marine habitat mapping, Cape Cod National Seashore: a post-Hurricane Sandy study. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2017. http://dx.doi.org/10.4095/305420.
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Boyle, Maxwell. Terrestrial vegetation monitoring at Cape Lookout National Seashore: 2022 data summary. National Park Service, 2024. http://dx.doi.org/10.36967/2303636.
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Parks within the Southeast Coast Network (SECN) host a diverse assemblage of plants and terrestrial vegetation communities. Vegetation communities are dynamic entities whose species composition, abundance, distribution, and structure are influenced by environmental factors and impacted over time by natural and anthropogenic disturbances. Determining trends in vegetation communities over time and identifying plant stressors is vital to understanding the ecological health of terrestrial ecosystems within SECN parks. Like most barrier islands along the southeastern coast, the vegetation communities along Cape Lookout National Seashore range from open beach and foredune grasslands on the ocean-facing side to tidal marshes on the sound-facing side. Between is a mixture of interdune swales, backdunes, and enclosed wetlands. Open upland vegetation is found on foredunes and occasional backdunes within the seashore. Cape Lookout National Seashore ecosystems are subjected to high frequencies of storm-, wind-, tide-, and wave-driven processes. Historic and current vegetation composition and structure are largely a result of these highly dynamic processes. Current vegetation patterns and processes across the Outer Banks are impacted and will continue to be impacted by rising sea-levels. Vegetation communities are vulnerable to overwash, which moves sand from the island?s ocean-side to the sound-side, brought on by more frequent and higher intensity storms. In 2019, Hurricane Dorian produced significant storm surge from the sound-side that overwashed the island and deposited sand into the ocean. Sand was scoured out from over 54 major cuts in the island, creating current ponds that are in various stages of succession. 2022 marked the first year of conducting this monitoring effort at Cape Lookout National Seashore. Forty-nine vegetation plots were established throughout the park in May and June. Data collected in each plot included species richness across multiple spatial scales, species-specific cover and constancy, species-specific woody stem seedling/sapling counts and adult tree diameter at breast height (DBH), overall tree health, landform, soil, observed disturbance, and woody biomass estimates. Data were stratified across four dominant broadly defined habitats within four park subunits: North Core Banks, South Core Banks, Cape Lookout, and Shackleford Banks. Broadly defined habitats monitored included: Open Upland Vegetation, Upland Forests and Shrublands, Nontidal Wetland Vegetation and Tidal Wetlands. One hundred and eighty-six vascular plant taxa were detected during this monitoring effort, including 11 taxa not detected in previous lists. Human-caused disturbances (e.g., historical plowing, shifting fire regimes, and altered hydrology) affecting plant communities within other SECN parks were not observed within these plots during this survey effort. Stunted plant growth was observed on several plots of Shackleford Banks and is likely caused by feral horse grazing. It is unclear from these data if grazing has impacted overall vegetation diversity and structure patterns across the island.
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Burkholder, JoAnn, Ellen Allen, Carol Kinder, Stacie Flood, and Wendy Wright. Natural resource condition assessment: Cape Lookout National Seashore. National Park Service, 2017. https://doi.org/10.36967/2240259.
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The two major goals of this report were to (i) inventory the natural resources of Cape Lookout National Seashore (CALO, or the seashore, or Cape Lookout NS) along the Outer Banks of North Carolina, including synthesis of available information and collection of geospatial data layers and maps; and (ii) develop a set of indicators, quantitative insofar as possible, for natural resource conditions that can be tracked over time. The natural resources that were evaluated included climate, air quality, geology and soils, groundwater, surface water, terrestrial, wetland, and aquatic biota, and species of special concern. This analysis emphasized the most recent years of available information through 2012, especially for water quality and biota, so that the national resource assessment and “Report Card” would target present/recent conditions. Cape Lookout is a dynamic barrier island system that forms the southern portion of the Outer Banks, one of the nation’s major natural, highly dynamic geological wonders, and among the most remote of national parks despite its close proximity to the mainland. It is about 11,430 hectares (28,244 acres [ac] or 44.1 mi2]) in extent, and more than one-third of the area is water. Its ocean side beaches span a length of 91 kilometers (56.5 miles [mi]), stretching from Ocracoke Inlet southwest to Beaufort Inlet. The three main barrier islands or “banks” of Cape Lookout—also known as part of the “Crystal Coast of North Carolina”—are only 1–2 kilometers (0.6–1.2 mi) wide. From north to southwest, they include North Core Banks, South Core Banks, and Shackleford Banks. The highest topographic features of Cape Lookout, sand dunes, rise approximately 3.7 meters (12.1 ft) above mean sea level on North and South Core Banks, and about 10–13 meters (32.8–42.7 ft) on Shackleford Banks. The seashore headquarters, on Harkers Island, hugs the mainland and is accessible by automobile, but the three barrier islands are accessible to the general public only by ferry service and there are no connecting roads. The ocean side seashore boundary is mean low tide, and the sound side boundary extends 45.7 meters (150 ft) from the shore into the water. Given this definition of park boundaries, together with accelerating sea-level rise from climate change, Cape Lookout NS boundaries area constantly shifting. Climate change is rapidly advancing in the Southeast—including Cape Lookout—and is manifested through warming temperatures, altered patterns and amounts of precipitation (droughts, floods), and storm frequency. The seashore sustains a high frequency of naturally occurring storm-, wind-, tide-, and wave-driven processes of erosion, accretion, and overwash that cause it to migrate landward. The narrow barrier islands of sand, very near to mean sea level, are extremely vulnerable to climate change impacts such as inundation from sea-level rise. The predicted changes would dramatically impact the natural resources of this seashore. Park staff and the Southeast Coast Network are proactively engaged in planning efforts to better prepare for those impacts. The Cape Lookout barrier islands are separated from the mainland by two shallow, narrow sounds, Core Sound and Back Sound, which are only 3.2–6.4 kilometers (2–4 mi) wide. In addition, the northwestern edge of North Core Banks abuts the wide expanse of Pamlico Sound (24–48 kilometers [15–20 mi]) in width. Moderate noise and light pollution from the Morehead City-Beaufort population center on the mainland likely adversely affect the closest barrier island, Shackleford Banks, which has been proposed as and is managed as a Wilderness Area by the National Park Service. Mainland water pollution impacts, such as chemical substances and sea trash, are a potential concern on the barrier islands. Air pollution from mainland urban and agricultural areas has caused poor air quality as an ongoing, serious problem in the seashore. Low fecal coliform bacterial densites indicate...
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Knight, R. D., and H. A. J. Russell. Quantifying the invisible: pXRF analyses of three boreholes, British Columbia and Ontario. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331176.
Full textAbstract:
Portable X-ray fluorescence (pXRF) technology collects geochemical data at a fraction of the cost of traditional laboratory methods. Although the pXRF spectrometer provides concentrations for 41 elements, only a subset of these elements meet the criteria for definitive, quantitative, and qualitative data. However, high-quality pXRF data obtained by correct application of analytical protocols, can provide robust insight to stratigraphy and sediment characteristics that are often not observed by, for example, visual core logging, grain size analysis, and geophysical logging. We present examples of geochemical results obtained from pXRF analysis of drill core samples from three boreholes located in Canada, that demonstrate: 1) Definitive stratigraphic boundaries observed in geochemical changes obtained from 380 analyses collected over 150 m of core, which intersects three Ordovician sedimentary formations and Precambrian granite. These boundaries could not be reconciled by traditional visual core logging methods. 2) Significant elemental concentration changes observed in 120 samples collected in each of two ~120 m deep boreholes located in a confined paleo-glacial foreland basin. The collected geochemical data provide insight to sediment provenance and stratigraphic relationships that were previously unknown. 3) Abrupt changes in the geochemical signature in a subset of 135 samples collected from a 151 m deep borehole intersecting Quaternary glacial derived till, sands, and ahomogeneous silt and clay succession. These data provide a platform for discussion on ice sheet dynamics, changes in depositional setting, and changes in provenance. Results from each of these studies highlights previously unknown (invisible) geological information revealed through geochemical analyses. A significant benefit of using pXRF technology is refining sampling strategies in near real time and the ability to increase sample density at geochemical boundaries with little increase in analysis time or budget. The data also provide an opportunity to establish a chemostratigraphic framework that complements other stratigraphic correlation techniques, including geophysical methods. Overall, data collected with pXRF technology provide new insights into topics such as spatial correlations, facies changes, provenance changes, and depositional environment changes.
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Pisutha-Arnond, Visut, Sirichai Sunmanee, and Sudham Yaemniyom. A report on copper skarn deposit at Phu Lon, Amphoe Sang Khom Changwat Nong Khai. Chulalongkorn University, 1988. https://doi.org/10.58837/chula.res.1988.18.
Full textAbstract:
Based on the geological and petrographical studies and chemical analysis of drill-core and outcrop samples, the geology and mineralization at the Phu Lon area are revealed. The Phu Lon prospect is a Cu-Fe-Au-Ag skarn deposit of porphyry-related type. The copper- and iron-rich zones are hosted predominantly in the garnet-pyroxene skarn that is developed metasomatically at the contact between the diorite-monzodiorite intrusions and a marble with minor calcsilicate unit. The main stage of iron mineralization probably took place during the prograde garnet-pyroxene skarn formation and was genetically related to the diorite-monzodiorite. The ore minerals include magnetite, minor chalcopyrite and pyrite, and occur in the form of massive patches or bands in the skarn. Quartz monzonite porphyry – monzonite dikes/stocks post-date the diorite-monzodiorite and the garnet-pyroxene skarn. Extensive alterations overprinting on both intrusive and volcanic rocks (i.e., potassic, phyllic and propylitic) are probably related to the cooling of quartz monzonite porphyry-monzonite. Close accompanying the alterations, the main stage of copper mineralization and retrograde skarn alteration of epidote-chlorite-calcite commenced. The mineralization occurs in the from of chalcopyrite-pyrite-quartz veins/veinlet networks predominantly in the skarn unit. Other associated minerals include magnetile, hematite and molybdenite. Trace amounts of gold and silver are chemically detected and probably associated with the copper mineralization. Their contents are comparable to those of the similar copper-gold deposit class. It is attractive for persuading further exploration.
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Peralta, Airy, and Chris Ray. Lagomorph ladders: Assessing a multi-host community and potential for spillover of rabbit hemorrhagic disease at Great Sand Dunes National Park and Preserve. National Park Service, 2024. http://dx.doi.org/10.36967/2303667.
Full textAbstract:
Rabbit hemorrhagic disease virus type 2 (RHDV2) has caused dramatic declines in rabbits and hares on several continents, with cascading effects on local ecology. Recent mortalities have been reported for several rabbit and hare species in the United States, suggesting broad susceptibility of lagomorphs. If this susceptibility extends to the American pika (Ochotona princeps), the most cold-adapted lagomorph, it could compound climate-mediated threats to this species. Due to climate change, American pikas are predicted to experience significant upslope range retraction during this century. Using an analogy borrowed from wildfire scenarios, other lagomorph species occurring at lower and mid-elevations could act as ?ladder fuels? to wick RHDV2 into high-elevation pika populations. To address this concern, we investigated spatial patterns of habitat use by pikas and other lagomorphs in Great Sand Dunes National Park and Preserve (GRSA), which borders several counties that have reported RHDV2. In 2022, we surveyed 115 plots from a spatially balanced sample of pika habitats in the park, including 48 legacy plots from a pika survey conducted in 2010-2012. Pika detections at the plot level were paired with topographic and environmental indices to estimate minimum habitat occupancy and determine its covariates. Leporid (rabbit and hare) detections at these same plots were used to model presence using similar covariates and correcting for imperfect detection. Our best-supported models of pika and leporid presence were then used to estimate the probability of contact between these taxa within the park. Our mean estimate of pika habitat occupancy was at least 95% during 2022 in GRSA, slightly higher than in 2010-2012, and effects of elevation and precipitation on pika occupancy were as expected from the previous study. Leporid presence at these same plots was 48% after correcting for imperfect detection. The best model of leporid presence supported a negative effect of elevation, in agreement with other studies of these taxa. The best pika and leporid models also included a positive effect of incoming solar radiation. Finally, we used our best models of pika habitat occupancy and leporid presence within the park to map the potential for areas of contact and RHDV2 transmission between these taxa. Our results indicate some potential for contact within subalpine forests, Specifically in the northern half of the park near the lower reach of the Sand Creek Trail and in the far south just north of California Peak.