bluuebunny/crossref_metadata_2025_split huggingface dataset:
Properties of Oil Well Cement Reinforced by Carbon Nanotubes
Authors: Rahimirad Mohammad , Baghbadorani Javad Dehghani 
Published: June 2012

Abstract
Nanotechnology is one of the most active research areas that encompass a number of disciplines including civil engineering and construction materials. Currently, the most active research areas dealing with cement and concrete are: understanding of the hydration of cement particles and the use of Nano-size ingredients such as alumina and Nano carbon tubes particles. CNT are expected to have several distinct advantages as a reinforcing material for cements as compared to more traditional fibres. First, they have significantly greater strengths than other fibres, which should improve overall mechanical behavior. Second, CNT have much higher aspect ratios, requiring significantly higher energies for crack propagation around a tube as compared to across it than would be the case for a lower aspect ratio fibre. Thirdly, the smaller diameters of CNT means both that they can be more widely distributed in the cement matrix with reduced fibre spacing and that their interaction with the matrix may be different from that of the larger fibres.
Using the CNT reinforced cement can reduce probability of casing collapse in oil and gas wells. Gas migration is one of the cementing problems in gas wells which using CNT in cement can reduce amount of gas migration.
Use of Modified Nanoparticles in Oil and Gas Reservoir Management
Authors: Turkenburg D. H. , Chin P. T. , Fischer H. R. 
Published: June 2012

Abstract
We describe a water dispersed nano sensor cocktail based on InP/ZnS quantum dots (QDs) and atomic silver clusters with a bright and visible luminescence combined with optimized sensor functionalities for the water flooding process. The QDs and Ag nano sensors were tested in simulated reservoir conditions (high salinity, Ca2+, pH, high temperature, oil and solids). The nano sensors showed enhanced sensor functionalities towards pH, temperature, sub-terrain chemistry and reservoir solids like clay or calcium carbonate.
Prospect Validation Methodology in Offshore Mature Fields: A Case Study
Authors: Grimaldi J. , Paranjpe V. , Segnini C. , Blanco L. 
Published: June 2012

Abstract
Repsol (operator), together with partners Petrotrin and National Gas Company of Trinidad and Tobago, took over operations of mature fields Teak, Samaan and Poui (TSP) Offshore Trinidad by end of 2005. With the intention of planning further development in the TSP reservoirs (comprising more than 10 vertically stacked main units, highly compartmentalized reservoirs with complex tectonic geometries) an indigenous comprehensive field evaluation was required. In order to perform a detailed analysis on all reservoirs, the effort would have been immense and would have delayed the decision making by years. Thus, a sand-by-sand Screening Project was carried out with the main objective of identifying the reservoirs with maximum potential so as to direct further technical effort on specific reservoirs for early monetization of the reserves.
Based on the results of sand-by-sand screening project, a prospect validation project for Teak Field was initiated - consisting of extensive field data acquisition, detailed interpretation and modeling workflows, adapted to the particular needs of mature fields. Several incremental opportunities identified during screening were validated and detailed modeling was performed to support further development. In some cases, the reservoir units that were identified to be having significant potential, turned out to be low on the priority list, as well as new and better than expected prospects appeared on the list. This paper outlines some examples and experiences from the prospect validation exercise.
On completion of this effort, the company acquired a holistic view of the asset in terms of projects and its remaining resources. So far, 21 localized static models and 15 dynamic simulation models have been completed resulting in the identification of 11 drilling candidates in Teak Field. A similar effort is planned for Samaan and Poui Fields in the near future. By dividing the problem into parts, the resources were optimized and the building-dynamic-model-for-everything was avoided.
Largest Integrated Asset Model (IAM) Enhances Trinidad’s Business Efficiency
Authors: Ryan S. , Hosein S. , Kromah M. , Bishop S. , Mihalik P. 
Published: June 2012

Abstract
The BP gas business in Trinidad is a complex multi-field, offshore business which supplies several long term gas contracts. Assets comprise 10 producing fields, prolific reservoirs and high rate producing wells. Gas volumes are transported via a complex processing and transportation network. This complexity necessitated the need for an integrated dynamic model that accurately simulates the physics of flow through the reservoir, well and surface system to improve production forecasting and identify system optimization opportunities. IAM provides this simulation capability.
The IAM model combines Trinidad’s complex facility network with hundreds of material balance and well models which allows for accurate simulation of flow through the system. This facilitates quantification of additional deliverability due to sequence optimization at any point in future production of the business.
IAM usage for production forecasting, scenario planning and for evaluating compression scenarios began in September 2008. IAM output analysis has informed several important business decisions such as choices around the continuity of the rig programmes, the timing and urgency of New Field Development options, the quantity and execution timing of opportunities required for gas supply, the cost and value of production capacity installed.
In this paper we discuss the process in building the Trinidad IAM model, learnings gathered from the model build and the future plans for using the IAM model for system optimization within bpTT.
Savonette Production Optimization While Preserving Well Integrity
Authors: Ramcharitar D. , Koylass A. 
Published: June 2012

Abstract
The SAVA01 well was the first well drilled in 2009 for the development of the Savonette field, with an expected deliverability of 250 mmscfd. During drilling of the well, an unsuccessful gravel pack job resulted in the well being plugged back in preparation for sidetracking. The well was successfully sidetracked and completed with contingent 4" screens. The screens however held up 21 ft from bottom leaving an excessive sump greater than the typical 8-10ft. An open-hole gravel pack job was performed and the well was completed with 7" production tubing. The additional sump created concerns about possible settling of gravel if not completely packed, causing ‘hot spots’ and eventual screen failure. The well was put on production in Oct 2009 based on a conservative ramp-up schedule and drawdown guidelines. At this time, the primary means of monitoring solids (sand) production was an online acoustic detector. As a result of the additional sump volume, the reduced screen size and the low yield (i.e. condensate to gas ratio) of the gas, an erosion assessment was completed to determine the safe operating envelope for the well. The results from the study recommended the well be constrained to a rate of 180 mmscfd until additional intrusive erosion monitoring equipment was installed. This was based on the limitation of the acoustic detector for monitoring solids production where sand loading &lt; 0.1 lb/mmscfd. Two (2) additional monitoring devices were installed on the well, an Intrusive ER Probe and online UT monitoring to effectively monitor longer term erosion-corrosion. The use of the wireless online Ultrasonic Testing (UT) monitoring system was the first application on a producing offshore well in the oil and gas industry.
In September 2011, the well was successfully increased to 230 mmscfd close to the original target and added significantly to the production deliverability to the business.
Analysis of the Genetic Diversity of Natural Populations of Alpinia oxyphylla Miquel Using Inter‐Simple Sequence Repeat Markers
Authors: Wang Haiyan , Liu Xiaojing , Wen Mingfu , Pan Kun , Zou Meiling , Lu Cheng , Liu Shisheng , Wang Wenquan 
Published: June 2012

ABSTRACTAlpinia oxyphylla Miquel is an endangered but economically valuable species. Given that it is one of the four most important medicinal plants in southern China, surprisingly few studies have characterized the species at the molecular level. In this study, 163 accessions were collected from seven natural populations of A. oxyphylla, along with one outgroup species, to investigate the genetic diversity of the species using inter‐simple sequence repeat (ISSR) analysis. A total of 365 polymorphic markers were detected from the general population when it was analyzed using 20 ISSR primers. Nei's genetic diversity and Shannon's information index were 0.2129 and 0.3373, respectively, indicating considerable genetic diversity at the species level. Less genetic differentiation took place among populations, with evidence of coefficient of gene differentiation 0.338 and gene flow 0.907, suggesting that there was more genetic variation within populations than between populations. An unweighted pair group method with arithmetic averaging dendrogram divided all accessions into eight groups that coincided almost completely with their geographical origin, with the exception of just a few crosses. This suggests that the geographic distribution of accessions coincided closely with the distribution of genetic diversity within A. oxyphylla, indicating weak gene flow. These results may provide valuable guidance regarding the conservation and genetic improvement of the species.
Day Temperature Influences the Male‐Sterile Locus ms9 in Soybean
Authors: Wiebbecke Christiana E. , Graham Michelle A. , Cianzio Silvia R. , Palmer Reid G. 
Published: June 2012

ABSTRACTCultivated soybean [Glycine max (L.) Merr.] is a major source of oil and protein in global food production. As demand for soy‐based products increases, it is essential for breeders to find ways to increase yield beyond conventional methods. Alternative methods of cultivar development and improvement must be identified. Our objectives were to determine if the ms9 locus conferring male sterility in soybean was environmentally sensitive and, if it were, to determine which environments could be used in hybrid seed production. This was accomplished through characterization of pollen phenotypes and selfed seed set among progeny of soybean genotype T359H (Genetic Type Collection number T359H), a heterozygous maintainer line for the ms9 locus. T359H was evaluated in seven environmental regimens in growth chamber experiments. We used a split‐plot design to test the effect of temperature regimens and male‐sterile phenotypic classifications within chambers. As day temperature increased from 30 to 35°C, selfed seed set on male‐sterile, female‐fertile plants decreased. Conversely, night temperature affected neither fertile nor male‐sterile, female‐fertile selfed seed set. This suggests that ms9 can be used in hybrid seed production in controlled environments where day temperature is 35°C during the flowering. These temperature conditions and their effect on ms9 may provide an alternative method to produce hybrid seed in soybean cultivar development programs.
Diversity of Seed Storage Proteins ofArachis hypogaeaand Related Species
Authors: Calbrix Raphael G. , Beilinson Vadim , Stalker H. Thomas , Nielsen Niels C. 
Published: June 2012

ABSTRACTThe diversity of seed storage proteins of cultivated peanut (Arachis hypogaeaL.) was studied by analyzing nucleotide sequences encoding 2S, 7S, and 11S seed storage proteins. Alignments of sequences were performed using ClustalX, and similarity between aligned sequences was established by pairwise comparison using AlignX. Three homology groups of 2S proteins were identified, which were further divided into three, three, and two subgroups. Similarly, three homology groups of 7S proteins contained two, two, and one subgroups; and five homology groups of 11S proteins contained five, five, five, three, and two subgroups. Primer pairs were identified that allowed each member of the respective homology group to be selectively amplified by polymerase chain reaction using template complementary DNA or genomic DNA fromA. hypogaea.This permitted most subgroup members to be distinguished. Peanut, like other legumes, contains small gene families encoding each type of seed storage protein. However, the diversity among these was greater than in other legume species, which reflects the allotetraploid nature ofA. hypogaea. Polymerase chain reaction amplifications from diploid species were used to deduce which protein subgroup originated from the A genome and which were from the B genome. Of the 26 diploid peanut species studied, onlyA. duranensisKrapov. and W.C. Greg. (A genome) andA. ipaensisKrapov. and W.C. Greg. (B genome) contained the correct complement of seed storage protein coding regions. This is consistent with the hypothesis that the center of origin of the allotetraploid was southern Bolivia.
Variation in Biomass Composition Components among Forage, Biomass, Sorghum‐Sudangrass, and Sweet Sorghum Types
Authors: Stefaniak Thomas R. , Dahlberg Jeffery A. , Bean Brent W. , Dighe Nilesh , Wolfrum Edward J. , Rooney William L. 
Published: June 2012

ABSTRACTAlternative biomass sources must be developed if the United States is to meet the goal in the U.S. Energy Security Act of 2007 to derive 30% of its petroleum from renewable sources, and several different biomass crops are currently in development. Sorghum [Sorghum bicolor (L.) Moench] is one such crop that will be an important feedstock source for biofuel production. As composition influences productivity, there exists a need to understand the range in composition observed within the crop. The goal of this research was to assess the range in dietary fiber composition observed within different types of biomass sorghums. A total of 152 sorghum samples were divided into the four end‐use types of sorghum: biomass, forage, sorghum‐sudangrass, and sweet. These samples were analyzed chemically using dietary fiber analysis performed at the National Renewable Energy Laboratory using published protocols. Significant variation among the groups was detected for glucan and ash. Positive and highly significant correlations were detected between structural carbohydrates in the biomass and sweet sorghums while many of these correlations were negative or not significant in the forage and sorghum‐sudangrass types. In addition, a wide range of variation was present within each group indicating that there is potential to manipulate the composition of the crop.
Effect of Recurrent Selection on the Genetic Structure of Two Broad‐Based Spanish Maize Populations
Authors: Romay M. Cinta , Butrón Ana , Ordás Amando , Revilla Pedro , Ordás Bernardo 
Published: June 2012

ABSTRACTMaize (Zea mays L.) landraces are useful materials that can introduce new diversity into breeding programs, but they will need to be selected to maximize their agronomic performance. The objective of this study was to use molecular markers to investigate the changes in the genetic diversity and structure over the cycles of a maize breeding program that combined intra‐ and interpopulation recurrent selection for grain yield in two broad‐based Spanish maize composites. Using 76 polymorphic simple sequence repeat (SSR) markers and two flowering time related indels, this study looked at 10 populations derived from a breeding program designed to exploit the heterotic pattern northern Spain × southern Spain. Agronomic evaluations demonstrated that the selection effectively increased the yield of the composites and their crosses, but, as the molecular data from this study show, the improvement was at the expense of some variability. The genetic distance between populations increased with selection, which is accordant with the increment of heterosis found in the agronomic evaluation. The changes observed were consistent with a model in which genetic drift is the main force, although selection could also play a role in the changes observed in EPS7 and EPS13. Allele frequencies changed significantly for one marker during intrapopulation selection and three markers under interpopulation selection, pointing to regions 3.04, 7.03, 9.01, and 9.03 as quantitative trait loci (QTL) related to grain yield.
Production and Economics of Steers Grazing Tall Fescue with Annual Legumes or Fertilized with Nitrogen
Authors: Interrante Sindy M. , Biermacher Jon T. , Kering Maru K. , Butler Twain J. 
Published: June 2012

ABSTRACTUse of cool‐season forage legumes may decrease production costs and improve returns to beef cattle (Bos spp.) producers. The objective of this 3‐yr field study was to compare the performance and economics of stocker cattle grazing tall fescue {Festuca arundinacea Schreb. [syn. Schedonorus arundinaceus (Schreb.) Dumort] ‘Texoma MaxQ II’} under two N systems. Paddocks (0.81 ha) were either a tall fescue with 112 kg N ha−1 (fertilized so that a total of soil residual N plus fertilizer would equal 112 kg N ha−1) (TF‐N) or contained a tall fescue with annual legume mixture (arrowleaf clover [Trifolium vesiculosum Savi], hairy vetch [Vicia villosa Roth], and field pea [Pisum sativum L.] (TF‐Leg). Steers (Bos taurus; 282 ± 67 kg initial body weight) were weighed every 28 d during each grazing season, and stocking rates were adjusted based on forage mass with put‐and‐take steers. In each 28‐d grazing period, forage mass, forage allowance, and stocker average daily gain (ADG) and total gain (TG) were measured. Results show a greater number of grazing days (429 and 334 d ha−1, respectively; p = 0.03) were associated with the TF‐N system than the TF‐Leg system while animal performance (ADG of 0.70 kg per head d−1; p = 0.61) and TG (296 and 237 kg ha−1; p = 0.10) were similar. The 3‐yr average total cost with establishment and gross revenue were similar between the TF‐N (US$460.67 and $691.16 ha−1, respectively) and TF‐Leg systems ($466.79 and $553.33 ha−1, respectively). However, the TF‐N system showed a tendency toward greater expected net return than the TF‐Leg system ($224.35 and $92.67 ha−1, respectively; p = 0.08).
Production and Economics of Grazing Steers on Rye–Annual Ryegrass with Legumes or Fertilized with Nitrogen
Authors: Butler Twain J. , Biermacher Jon T. , Kering Maru K. , Interrante Sindy M. 
Published: June 2012

ABSTRACTCool‐season legumes have potential to replace N fertilizer in annual cool‐season grass pastures, thus improving returns to producers. The objective of this 3‐yr study was to compare the performance and economics of stocker cattle (Bos spp.) grazing rye (Secale cereale L.)–annual ryegrass (Lolium multiflorum Lam.) under two N systems. Paddocks were planted in early September 2008 through 2010 and contained rye–annual ryegrass with 112 kg N ha−1 (fertilized so that a total of soil residual N plus fertilizer N would equal 112 kg N ha−1) (RR‐N) or contained a rye–annual ryegrass with annual legume mixture (arrowleaf clover [Trifolium vesiculosum Savi], field pea [Pisum sativum L.], and hairy vetch [Vicia villosa Roth]) (RR‐Leg). Steers (307 ± 55 kg initial body weight) were weighed every 28 d and stocking rates were adjusted based on forage mass with put‐and‐take steers. Forage mass, forage allowance, and stocker average daily gain (ADG) and total gain (TG) were measured every 28 d. Results show similar performance between RR‐N and RR‐Leg systems in grazing days (average 367 d ha−1), ADG (average 1.065 kg per head d−1), and TG (average 390 kg ha−1). While the 3‐yr average total cost associated with the RR‐N system (US$569.88 ha−1) was greater than the RR‐Leg system ($550.57 ha−1), there were no differences in gross revenue (average $815.91 ha−1) or expected net returns (average $255.68 ha−1) between systems. Annual legumes could be a viable replacement for commercial N fertilizer in rye–annual ryegrass pastures although adoption may be limited due to ease of N fertilizer application.
Identification of Quantitative Trait Loci Linked to Drought Tolerance in a Colonial × Creeping Bentgrass Hybrid Population
Authors: Merewitz Emily B. , Belanger Faith C. , Warnke Scott E. , Huang Bingru 
Published: June 2012

ABSTRACTIdentification of quantitative trait loci (QTL) for drought tolerance will allow for detection of important genomic regions associated with specific drought tolerance traits. This study aimed to identify QTL for drought tolerance traits in a colonial bentgrass (Agrostis capillaris L.) × creeping bentgrass (Agrostis stolonifera L.) hybrid backcross population. The traits included relative water content (RWC), turf quality (TQ), electrolyte leakage (EL), chlorophyll content (CHL), normalized difference vegetation index (NDVI), and canopy temperature depression (CTD). A colonial × creeping bentgrass hybrid backcross population segregating for drought tolerance was exposed to drought stress by withholding irrigation in three different locations or environmental conditions (two greenhouse studies in two different years, 2009 and 2010, and a growth chamber study in 2010). Phenotypic trait data were collected in these studies. Significant variation in the parents and the progenies occurred for phenotypic traits and the broad‐sense heritability values indicated that the traits were polygenic in nature. A total of 32 potential QTL of varying effects (31 major and 1 minor) were detected on seven chromosomes. Significant overlap of QTL was found, particularly for CHL and CTD on 1A1, CTD, CHL, EL, and NDVI on linkage group 2A1, CTD and TQ on 2A2, TQ and RWC on 5A1 and 5A2, and TQ and CHL on 5A2. The QTL with the strongest effect for each trait (highest likelihood of the odds [LOD] and percent of phenotypic variance explained by the QTL) were CTD (4.19, 18.8%), CHL (4.23, 18.9%), EL (3.25, 14.9%), and NDVI (4.12, 22.4%) on group 2A1, RWC (3.27, 15.7%) on group 5A1, and TQ (4.38, 19.5%) on group 5A2. The analysis of potential genes in the QTL regions for these physiological traits indicate that the QTL may be linked to metabolic factors involved in N metabolism and energy metabolism such as photosynthesis and respiration. The QTL regions identified here could contain important genetic factors conferring drought tolerance in bentgrass species.
Probing the QCD phase boundary with elliptic flow in relativistic heavy ion collisions at STAR
Authors: Shi Shusu 
Published: June 2012

Abstract
We present measurement of elliptic flow, v
2, for charged and identified particles at midrapidity in Au+Au collisions at $\sqrt {s_{NN} } $ = 7.7–39 GeV. We compare the inclusive charged hadron v
2 to those from transport model calculations, such as the UrQMD model, AMPT default model and AMPT string-melting model. We discuss the energy dependence of the difference in v
2 between particles and anti-particles. The v
2 of ϕ meson is observed to be systematically lower than other particles in Au+Au collisions at $\sqrt {s_{NN} } $ = 11.5 GeV.