bluuebunny/crossref_metadata_2025_split huggingface dataset:
Corrosión por nido de hormigas de tubos de cobre utilizados en sistemas de aire acondicionado
Authors: Bastidas D. M. , Cayuela I. , Bastidas J. M. 
Published: October 2008

Corrosión por “nido de hormigas” es un tipo específico de fallo prematuro (2-3 meses) que tiene lugar en tubos de cobre utilizados en sistemas de aire acondicionado originando la pérdida de líquido refrigerante y la consecuente contaminación ambiental. Es conocido que este tipo de ataque requiere la presencia simultánea de humedad, oxígeno y un medio agresivo, habitualmente un ácido orgánico, como fórmico, acético propiónico o butírico u otras sustancias orgánicas volátiles tales como metanol, etanol, formaldehido o acetoaldehido. Aproximadamente el 10% de los fallos prematuros en tubos de cobre utilizados en calefacción, ventilación y en la industria de aire acondicionado son el resultado de corrosión por nido de hormigas. Frecuentemente, este tipo de corrosión tiene lugar en tubos de cobre de pared delgada, especialmente cuando el cobre es del tipo desulfurizado, y se conoce con varios nombres: corrosión por ácido fórmico, corrosión no habitual, picaduras ramificadas, corrosión con forma de alfiler, etc.
Estudio tipológico y funcional de las toberas del yacimiento de la Fonteta (Guardamar del Segura, Alicante)
Authors: Renzi Martina 
Published: October 2008

El yacimiento fenicio de La Fonteta (Guardamar del Segura, Alicante), gracias sobre todo al descubrimiento de numerosos vertederos metalúrgicos, ha proporcionado abundantes materiales relacionados con la producción de hierro, cobre, cobre/plomo y bronces binarios y ternarios, y probablemente también con la obtención de plomo y de plata. Entre estos restos arqueometalúrgicos hay que destacar por cantidad y variedad un significativo conjunto de toberas, constituido por más de 400 fragmentos. Las piezas documentadas hasta ahora se enmarcan en un arco cronológico que va desde los comienzos del siglo VIII a.C. hasta finales del siglo VII a.C. Actualmente, este conjunto de toberas se puede considerar el más abundante y variado conocido en un yacimiento fenicio de la Península Ibérica, y el estudio de este material nos permitirá definir la variabilidad de las formas y observar si ese cambio formal responde a algún factor tecnológico vinculado con actividades metalúrgicas o con el tipo de producto metálico procesado. Para ello, en este artículo definiremos los tipos, su frecuencia en las diferentes fases, su contexto de aparición y, en los casos en los que haya sido posible, se presentarán los resultados obtenidos por el análisis elemental de los restos escoriaceos adheridos a las bocas de estas toberas.
Glomar Challenger - Deep Sea Drilling From Texas To Dakar
Authors: Field A.J. , Thornburg Russell B. , Crooke R. Curtis 
Published: October 2008

Introduction
The paper "Glomar Challenger - Deep Sea Drilling From Texas To Dakar" consists of a recently completed documentary film covering project background, and design construction and operation of the Glomar Challenger during the initial legs of the Deep Sea Drilling Project.
The following notes are intended simply for the viewers information and possible future reference. The Deep Sea Drilling Project is a portion of this Government's Ocean Sediment Coring Program, directed towards obtaining deep sea cores for scientific analysis throughout the Atlantic and Pacific Ocean basins. The Project is an outgrowth of a proposal initially prepared by the JOIDES Group. Participants of JOIDES include Scripps Institution of Oceanography (currently Manager of the Deep Sea Drilling Project), Woods Hole Oceanographic Institute, Lamont Geological Observatory, The Institute of Marine Science and, a current addition, the University of Washington. The program is funded and administered by the National Science Foundation on behalf of the U. S. Government.
Initial drilling operations commenced on August 12, 1968 in the Gulf of Mexico, and are currently being carried out in the Caribbean prior to the start of operations in the Pacific Ocean in April, 1969. A summary of the highlights of the program to date (March, 1969) include the following:Number of locations occupied to date: 28Number of holes drilled to date: 49Maximum water depth drilled to date: 18,157 ft.Minimum water depth drilled to date: 6,355 ft.Maximum penetration into sea floor: (Hole 9A) 2, 759 ft.Maximum length of drill string: (Hole 28) 19,483 ft.Principal dimensions and characteristics of the Glomar Challenger are as follows:Length Over All: 402 ft.Beam: 65 ft.Molded Depth: 26 ft. 9 in.Designed Draft: 20 ft.Designed Displacement: 10,500 long tonsDynamic Positioning System

a. Twin main screws: 2250 hp per shaft (underway propulsion)
The Glomar Challenger is provided with a fully automatic position sensing and control system capable of maintaining the ship in position to an accuracy of ± 200 ft. in a 45 knot head wind combined with a 1 1/2 knot beam current.
The performance of the Glomar Challenger to date has been extremely satisfactory, and this significant step forward in advanced offshore drilling technology represents a remarkable achievement on the part of the offshore drilling industry.
The Offshore Mercury
Authors: Sharp Frank W. 
Published: October 2008

ABSTRACT
This paper describes the design process in the development of a new concept in exploratory drilling tools. It examines the requirements for satisfactory design of a ship in a drilling platform and an elevating system. The design efforts are brought together to form in one unit a cohesive drilling tool - the self propelled, self-elevating drill ship - The Offshore Mercury.

THE OFFSHORE MERCURY
The Offshore Mercury, the industry's first self-propelled and self-elevating drill ship, presents a new concept of mobility and stability in offshore exploratory drilling. It accomplishes the heretofore impossible combination of economical mobility comparable to the self-propelled drill ship with the superior stability and drilling reliability of the jack up platform. The realization of this new concept is the result of an extensive design effort. We wish to trace some design considerations involved in producing the Offshore Mercury.
The first consideration is mobility. In our phase of the industry, this means moving on the sea. Move a drilling operation at sea? Easy; mount it on a buoyant box. That is a start. Push or pull it with tug boats. We do that now essentially, but we have to depend on getting the tugs out on time and having good weather to tie the tugs on and, besides, it is expensive. Let us remove the dependence on tugs; do it ourselves and make a sizeable saving on trip insurance. We have plenty of power for the rig, so hook it up to propellers and go it alone - anytime we are ready - anywhere we want to go. There you have it - a self-propelled drill ship.
Almost. Let us backtrack to the point of the buoyant box that we mounted the drilling equipment on. Basically, a box that floats works out fine for the preliminary criteria. But how about the refinements that make the whole thing workable, such as how fast is a box, and how safe is this rig in rough weather? What makes a box a ship? First we must make the box big enough to carry the drilling equipment. Experience can tell us that the drill rig will be about the same size as our rig "Orion" in the North Sea. So, we first take an Orion-shaped box and look at the speed. Not too good at 3 to 4 knots even with those big tugs pulling all out. Must be something to do with the shape of the bow. "Orion" is blunt in the bow. Let us add some shape to the bow to make the water flow by more easily.
This was a problem for the naval architects and the model test tanks. They took some known relationships and came up with a double curvature surface which should suit the problem. They then put the idea into a wooden model and placed it in the test tank. Based on the results of this test, they predicted an obtainable speed of about 8 knots. This is a big improvement over Orion and her tugs.
Wave-Structure Interaction In Offshore Platforms
Authors: Rivas Alberto Gomez 
Published: October 2008

ABSTRACT
The analysis of the complex interaction of wave forces and structural response is in its very early stages of development. Formulating the equation of motion for the structure under the action of wave forces involves the following uncertain parameters: [1] virtual water mass, which is a function of the relative velocities of the wave and the structure, and [2] drag forces, which are also a function of the relative velocities. Basic research is now needed to formulate a satisfactory equation of motion for the structure, based on these parameters. A computer model was developed to predict the dynamic response of structure inthe wave environment. Models were built and tested to check the computer model. The analytical and experimental results demonstrated the importance of the virtual mass and drag forces in formulating the equation of motion.

INTRODUCTION
The reliable prediction of the response of an offshore platform to wave action requires knowledge about the interaction of the wave and the structure during motion. With the structural system defined for its topological and mechanical characteristics and with the wave known or estimated, response follows from application of proper theory.
The design and construction of harbors is one of the oldest engineering applications. Ever since the port of A-ur was built on the Nile prior to 3000 B.C., there has been a continuous search for an understanding of the forces exerted by waves on marine structures. The forces exerted by waves on circular piles, plates, barge-like structures, vertical walls and breakwaters have been predicted by analytical methods and measured in the laboratory. The consensus of the investigators is that water particle velocity and acceleration are the governing parameters of the hydrodynamic forces exerted by waves on structures.
It should never be overlooked that the investigators always mean relative velocity of the water particle with respect to the body upon which the force is exerted. The same statement is true with regard to accelerations. This fact is often overlooked because most structures used in harbor engineering are very rigid and consequently the water velocities and accelerations with respect to the body are numerically equal to the velocities and accelerations with respect to ground. This is not the case for some offshore platforms that are flexible enough to have velocities and accelerations in the same order of magnitude as the water velocities and accelerations.
Fig. la presents a cylinder rigidly attached to a stiff support. The force F exerted by the wave on the cylinder can be computed by the formula proposed by Morison, O'Brien, Johnson and Shaaf.2F = Cl V2 L + C2 A L,..... [1]
where V and A are the water particle velocity and acceleration, respectively; Cl and C2 are constants defined by the geometry of the body, in this case a cylinder; and L is the length of the cylinder.
Since the cylinder is rigidly attached to the supports of infinite stiffness, its displacement under the action of the wave forces is zero.
Modal Study of a Submerged Buoyant Tank in Waves
Authors: Wiegel R.L. , Dilley R.A. , Whisenand S.F. , Williams J.B. 
Published: October 2008

ABSTRACT
One possibility for storing the oil produced by an offshore well is to make use of a moored submerged buoyant tank. Tests were conducted with a 1:49 scale model of such a tank, with neutral buoyancy mooring lines, in the 6 ft. deep by 8 ft. wide by 200 ft. long Wave-Towing Tank, University of California, Berkeley, under contract to the California Research Corporation (presently the Chevron Research Corporation).
The "prototype" was a circular cylinder approximately 190 ft. long by 22½ ft. in diameter with hemispherical heads, with an empty weight of 874 kips, and with a 60½ ft. longitudinal radius of gyration. Two general series of tests were conducted:Vertical mooring lines only, andvertical, breast, bow, and stern mooring lines.
The "prototype" water depth was 245 ft. and the top of the submerged tank was 185 ft. above the bottom Measurements were made of mooring line forces and tank motions with the model in head, quartering, and beam seas.
For the case of vertical mooring lines only, it was found that the dynamic force in the mooring lines due to wave action could be predicted rather well for beam seas by use of the "wave force on a pile" theory. Furthermore, it was found that the limits of dynamic forces could be predicted for the model in head seas using the same theory. The high forces measured in the vertical mooring lines due to a shifting of the buoyancy load from one line to another, when they were not exactly parallel, leads to the conclusion that extreme care will be necessary during installation. The greatest motion of the tank occurred in head seas in waves of 21 sec., prototype (the same value as the natural period of surge of the moored tank), with the surging motion of the tank being as much as 6 times the wave height and 4 times the total horizontal motion of the surface water particles.
When breast, bow, and stern mooring lines were added to the system, the motion of the submerged buoyant tank became negligible. It was found, however, that at some point in the transference of the buoyant force from the vertical to the lateral mooring lines (the percentage load transference depending upon the wave height and period to which the system was subjected) the vertical mooring lines would just slacken at one point in the cycle. This resulted in an impact type of loading upon take-up with high forces and considerable vibration. The magnitude of the peak force under these conditions could not be estimated due to the response characteristics of the force recording system.

SUBMERGED BUOYANT TANK MODEL MOORING LINES
A plexiglass tube was used for the tank and aluminum tubes were used for the mooring lines. Availability of plexiglass tube sizes (one being 5.5 in.O.D., 1/8 in. wall thickness) fixed the scale at 1:49 as the closest possible to the desired scale. This geometric scale fixed the time scale as 1:7.0 and the force scale at 1:117,650.*
Extraction of Methane from Oceanic Hydrate System Deposits
Authors: Max Michael  D. , Cruickshank Michael J. 
Published: October 2008

Abstract
No one to date has outlined an economic and safe method for sustained recovery of methane from the newly discovered low-grade oceanic hydrate and associated gas deposits. The potential rewards of unlocking the methane hydrate energy bank are potentially very great. The prize is possibly centuries of energy independence for some industrial states including the United States and Japan, and developing countries such as India, which appear to have considerable deposits of methane hydrate immediately adjacent to their landmasses. A number of nations, including the United States, have established, or are considering establishing, national hydrate research programs.

Introduction
Oceanic hydrate system deposits, which include both methane hydrate and associated methane gas, are very large, but relatively low grade when compared with conventional hydrocarbon deposits. They differ in character from conventional hydrocarbon deposits in almost every respect except that they encompass significant concentrations of hydrocarbon. It is now not immediately obvious in detail exactly how the methane from oceanic hydrate and related gas deposits will be recovered. It is not even certain whether hydrate or associated gas, or both, will be the preferred initial and eventual best economic target.
We examine some of the emerging issues likely to govern hydrate recovery and seafloor stability, and suggest geological models for oceanic hydrate system exploitation.

Methane hydrate; its disposition and recognition
Methane hydrates(CH4?6.1(±0.1%)H2O] are found in the low temperature-low pressure regimes of permafrost regions and high pressure-moderate temperature (from just below zero degrees C up to about 35 °C max) in ocean sediments. Methane hydrate is stable in seafloors below about 450 meters water depth in open ocean with an average temperate hydrothermal profile that gives hydrate a wide pressure-temperature field of stability1. Methane molecules are compressed closely together in the hydrate lattice. 1 m3 of hydrate yields about 160 m3 CH4 at STP and a residue of 0.87 H2O m32.
The hydrate forms in a zone of thermodynamic equilibrium, the Hydrate Stability Zone (HSZ) that extends downward from the seafloor to some depth determined by increasing temperature (Fig. 1). The base of the HSZ is a phase boundary. At constant geothermal gradients the thickness of the hydrate stability zone increases with increasing water depth and increased pressure. Where higher molecular weight thermogenic gases, such as ethane, butane, or propane occur, the hydrate stability field expands considerably. 1% propane in the gas mixture, for instance, can reduce the pressure at which the hydrate forms by nearly 40%1.
Figure 1. Position of the HSZ with respect to the hydro-and geothermal gradients and the methane hydrate phase boundary.(Available in full paper)
Vision of Growth for Trinidad and Tobago Natural Gas Industry
Authors: Wight David G. 
Published: October 2008

Abstract
Trinidad and Tobago continues to develop a world-class natural gas industry as the economy transforms from a predominantly oil-based economy to one, increasingly fuelled by gas. The country is poised for significant additional growth in gas and gas-based industries as the relatively large gas resource pool continues to be enhanced through successful exploration and the discovery of new resources.
With its solid reserve base, stable political climate, reliable economy, proximity to market and competitive market focus, Trinidad and Tobago continues to enjoy as good as, if not a better opportunity set than any country in the world, for further developing the natural gas business. We, at BP Amoco, have had a mutually beneficial relationship with the government and people of Trinidad and Tobago and remain committed to partnering in the future development and growth of the energy business in Trinidad and Tobago.

Introduction
The Republic of Trinidad and Tobago has an oil and gas industry that predates the modern petroleum industry (Ref. 1). The first successful well was reportedly drilled in 1866 in south Trinidad. Commercial oil production began in 1908 and for the next sixty years the emphasis was on oil production. Natural gas was considered then more of a nuisance than a benefit, and the unavoidable associated gas produced with the oil was limited to providing fuel and gas lift for maintaining oil production.
Commercial use of natural gas began in 1959, when Federation Chemical Ltd., a subsidiary of W. R. Grace, pioneered the use of natural gas as a feedstock to manufacture anhydrous ammonia. The next historical milestone for natural gas came five years later when commercial consumption increased with the use of gas as a primary fuel for electric power generation. In 1969, Amoco Energy discovered significant gas reserves in its license area off the East Coast. This discovery was followed in 1975 by the formation of The National Gas Company (NGC) of Trinidad and Tobago. The NGC was chartered to manage and sell natural gas. In discharging their role, they have facilitated the impressive expansion of the natural gas industry that has been seen from 1990 to 1997. The following sections discuss the country's strong gas resource base, the Government's aggressive market pursuits, rapidly expanding infrastructure and the security of gas supply situation: all ingredients for creating a vision of significant growth in the natural gas industry.

Growth of the Natural Gas Industry in Recent Years
The Natural Gas industry in Trinidad and Tobago has demonstrated continuous growth with gas sales increasing by approximately eight percent per year from 1990 to 1997. The country's Minister of Energy and Energy Industries, Senator Finbar Gangar, in his address to the Centre for Global Energy Studies Conference in London (Ref. 2) was quoted as saying Currently, Trinidad and Tobago is in the midst of an intense industrialisation thrust, with a major focus on the utilisation of natural gas as the main driver of this thrust."
Future Development of Gas Industry of Trinidad and Tobago
Authors: Kin Frank Look , Harnanan Clarence 
Published: October 2008

Abstract
The paper presents a review of the development of the gasindustry in Trinidad and Tobago. The role of The National Gas Company of Trinidad and Tobago Limited in the development of this industry is discussed.
The paper reviews the upstream and downstream operations, the pipeline network system and future development in these aspects of the gas industry.
The factors which make Trinidad and Tobago an attractive country for foreign investor in the gas industry both at upstream development and gas utilization are examined.
The natural gas sector of the economy has become the leading economic sector due to the government's policies with respect to the use of the natural gas reserves and the promotion and development of a range of petrochemical and gas based industries and the provision of fiscal and other incentives. Given the present state of industrial development, the future development of this industry is of significant importance.

Historical Review
The history of the energy sector dates back to the latter part of the nineteenth century. The first successful oil well was drilled in South Trinidad in 1866 and commercial production commenced in 1908. During the period 1908 to the 1960's the emphasis was on the production of crude oil. Associated gas which was produced with the crude oil was considered a nuisance and flaring of natural gas was wide spread in the industry.
The natural gas industry in Trinidad and Tobago dates back to early 1940's when gas produced as associated gas was used as a fuel and for gas lifting operation. During this period natural gas was piped to the oil company's housing areas in Point Fortin, Penal, Forest Reserve, Palo Seco and Guayaguayare for water heating and cooking. Gas lift operations and gas injection for secondary recovery of crude oil were fairly widespread in the oil producing areas of Trinidad and at one time there were up to 20 compressor stations dedicated to this production method and pressure maintenance respectively.
Natural gas was first used commercially as a fuel for power generation at the Penal power station in 1953 and at Trinidad Cement Limited, Claxton Bay in 1954. In 1959, the establishment of the first anhydrous ammonia plant in the country by Federation Chemicals Limited was based on natural gas as a feedstock for the manufacture of ammonia. This was followed by the expansion of natural gas usage for country wide generation of electricity when the power plant in Port of Spain commenced use of natural gas in 1964. This growth in the demand for natural gas in the sixties required the development of the pipeline infrastructure to support the expanded use of natural gas. The first was the construction of a 16-inch pipeline from Penal to Port of Spain.
In 1968 the country's most significant discovery of natural gas off the south east coast of Trinidad was made by Amoco Trinidad Oil Company.