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The purpose of this paper is to develop an autoclave that can be used to assess corrosion behaviour of suitable material in high-pressure–high-temperature (HPHT) environments. Many new discoveries of oil and gas field are in HPHT environments. The development of such fields requires appropriate selection of materials that are able to withstand not just the service loads but also corrosive production fluids in the HPHT environment.

The exposure of material samples to elevated pressure and temperature is usually done using an autoclave. The suitability of an existing autoclave for HPHT corrosion studies is provided together with suggestions on necessary design modifications. An alternative design of the autoclave is proposed based on functionality requirements and life cycle cost assessment.

It is concluded that the existing autoclave was unsuitable for HPHT corrosion tests, and modifications were very expensive to implement and/or not foolproof. A new autoclave was designed, manufactured, tested and successfully used to study the effect of aqueous solution on the corrosion of a pipe subject to a combination of axial tension, internal pressure and elevated temperature.

The maximum design pressure of 15 MPa is more than sufficient for high-pressure corrosion studies in aqueous solution where partial pressure of the dissolved gas is one of the main controlling parameters. However, the design pressure is only suitable for corrosion studies in a seawater environment of up to 1,500 m water depth.

A new design of autoclave together with all the necessary piping, assembly and control system is proposed for HPHT corrosion studies. The autoclave can be used as standalone or integrated with a mechanical testing machine and thus enables corrosion studies under a wide range of loading.

The purpose of this paper is to investigate the mechanical properties changing of geopolymer cement under different brine salinity.

Geopolymer Cement of Class F Fly Ash and Class G Cement slurries were prepared according to API RP 10B. The optimum alkaline activator/cement and water/cement ratio of 0.44 was used for geopolymer and Class G cement samples, respectively. The alkaline activator was prepared by mixing the proportion of Sodium Hydroxide (NaOH) solutions of 8 M and Sodium Silicate (Na2SiO3) using ratio of 1:2.5 by weight. The slurries were cured for 24 hours at 130^oC and 3,000 psi in HPHT Curing Chamber followed by coring process. Both cement sample were immersed in brine water salinity up to 28 days with different brine salinity up to 30 per cent of NaCl. The mechanical properties were investigated using OYO Sonic Viewer-SX and Uniaxial Compressive Strength. The surfaces of the cement samples were extracted for Scanning Electron Microscope (SEM) and EDS tests to evaluate the morphology and chemical compositions of the cured samples.

The paper shows that geopolymer samples experiences strength reduction in brine water but the reduction rate of geopolymer is about half of the Ordinary Portland cement based oil well cement. The finding was also verified by SEM and EDS result.

This paper investigates the mechanical property changes of emerging geopolymer cement due to different water salinity. The results provide potential application of geopolymer cement for oil well cementing.

The purpose of this paper is to investigate the resistivity of geopolymer cement with nano-silica additive toward acid exposure for oil well cement application.

An experimental study was conducted to assess the acid resistance of fly ash-based geopolymer cement with nano-silica additive at a concentration of 0 and 1 wt.% to understand its effect on the strength and microstructural development. Geopolymer cement of Class C fly ash and API Class G cement were used. The alkaline activator was prepared by mixing the proportion of sodium hydroxide (NaOH) solutions of 8 M and sodium silicate (Na₂SiO₃) using ratio of 1:2.5 by weight. After casting, the specimens were subjected to elevated curing condition at 3,500 psi and 130°C for 24 h. Durability of cement samples was assessed by immersing them in 15 wt.% of hydrochloric acid and 15 wt.% sulfuric acid for a period of 14 days. Evaluation of its resistance in terms of compressive strength and microstructural behavior were carried out by using ELE ADR 3000 and SEM, respectively.

The paper shows that geopolymer cement with 1 wt.% addition of nano-silica were highly resistant to sulfuric and hydrochloric acid. The strength increase was contributed by the densification of the microstructure with the addition of nano-silica.

This paper investigates the mechanical property and microstructure behavior of emerging geopolymer cement due to hydrochloric and sulfuric acids exposure. The results provide potential application of fly ash-based geopolymer cement as oil well cementing.

This paper aims to provide an insight into the main parameters that govern corrosion mechanisms in production tubing of oil and gas wells.

Corrosion has been an old concern for the oil industry. None of the three major sectors of the oil industry, namely, upstream, midstream and downstream, are immune of corrosion attacks. However, the upstream sector (oil and gas production facilities) is more vulnerable to corrosion because of its extreme conditions such as high temperature and pressure, multiphase flow, complicated water chemistry, presence of acidic gases, etc. This paper is a general review of the influence of such parameters on corrosion mechanisms of oil and gas wells.

In recent years, many technical papers have been published in this area. However, none of them provide a general review of the all contributing parameters on corrosion under field conditions.

Modeling and corrosion mitigating processes under downhole conditions require a thorough understanding of the influencing parameters. This paper aims to provide an insight into the main parameters that govern corrosion mechanisms in production tubing of oil and gas wells.

Strategic management.

Upper-level undergraduate courses or introductory MBA courses.

The need to diversify the financial risks of his scrap metal business based in Georgia led Levan to invest in a diamond trading company in the UAE. He agreed to be a sleeping partner and provide the capital to Kewon, a diamond specialist with a wealth of experience in the field, in their joint attempt to build an international network of diamond trade. Despite several difficulties faced on the way, their company seemed to generate stable returns for more than five years. Yet following the surprising discovery of multiple organizational inconsistencies, Levan decided to end the partnership with Kewon and establish his own retail jewelry store to be managed by the members of his family. Ultimately, he was confronted with two important decisions regarding both his jewelry business and the diamond company in which he had previously invested a significant amount of capital. The decisions he was about to make were of critical importance for the future of these companies and the people who managed them. By walking readers through a series of triggering events, this case offers the opportunity to evaluate the effectiveness of managerial actions through the application of various strategic management tools and frameworks.

Upon completion of this case study analysis, students should be able to: estimate the complexities associated with the management of a partnership-based venture in the context of emerging markets; perform a detailed diagnosis of an entrepreneurial venture, applying relevant strategic management tools and techniques; evaluate the effectiveness of managerial actions and decisions at different stages of the organizational lifecycle; and demonstrate the importance of the strategic adaptation of organizations through the deployment of viable decision-making skills.

Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

CSS 11: Strategy.

To maintain the well integrity, the strength and sealing ability of premium connection should be in the safe scope. ISO 13679 is widely used for evaluating the ability of tubing and casing connection all over the world. FE is adopted to simulate the ISO 13679 tests.

Because of the disadvantage of experiment such as long period, high cost and high requirement on the facility, considering the convenience and universality of finite element method, as well as the contacting nonlinearity and material nonlinearity, three-dimensional finite element model of a certain type of premium connection is established with the consideration of helix angle. The loads exerted on the premium connection are the loads in series B test and thermal cycle test of ISO 13679. The distributions of Von Mises stress and contact pressure in various cases were studied.

The results showed that the bending load has a great influence on the distribution of Von Mises stress and contact pressure for premium connection. The Von Mises stress and contact pressures on the sealing surface are smaller on the tension side and greater on the compression side. With increasing axial compression load, the contact pressures on the tension side are too small, which may lead to sealing failure. The influence of temperature on the performance of premium connection cannot be ignored when choosing or designing premium connections. Both the Von Mises stress and contact pressure decrease slightly during a period of thermal cycle. Although the performance of the premium connection is good in a period of thermal cycle, its performance in a long period should be evaluated. Finite element simulation can effectively simulate the ISO 13679 test procedure and obtain the stress and contact pressure distribution. It can be used as a reference for evaluating the performance of premium connections.

Considering the convenience and universality of finite element method, as well as the contacting nonlinearity and material nonlinearity, three-dimensional finite element model of a certain type of premium connection is established with the consideration of helix angle.

This research studies private information from extreme price movements or jumps. The authors calculate the private information using a reduced form model from the stochastic volatility jump process and use several statistical robustness tests as well as several frequencies to improve our consistency. This study reveals that private information is significant in explain the existence of jumps in capital markets in Southeast Asia, whereas macroeconomic events cannot explain them. The authors determine empirically that private information in Malaysia, Singapore, Thailand, and Indonesia are not persistent and its value gradually decreases when we use the lower frequency. Based on the Fama–Macbeth regression, this study shows that private information in the capital market has a strong positive relationship with individual returns in Indonesia’s capital market and Thailand’s capital market for all frequencies.

In this paper, we aim to understand why consumers often prefer products made using traditional practices even when products made using new practices are not of lower quality. We argue that this resistance, which we call “production process conservatism,” is heightened when the product is used in the performance of a social ritual.

We develop this argument in the context of diamond jewelry, as consumers have generally been resistant to diamonds that are produced in laboratories, i.e., lab-created diamonds. Hypotheses were tested using experiments conducted with an online sample (Experiment 1) and with an MBA student sample (Experiment 2).

In Experiment 1, we find that married female respondents significantly prefer mined diamonds to lab-created diamonds when they are used as part of an engagement gift as opposed to a more routine gift. In Experiment 2, we find the same effect among women; in addition, the perceived risk associated with the ritual is found to mediate this production process conservatism.

This paper contributes to the understanding of a macrosocial phenomenon – acceptance of an innovation – by examining microinteractive processes in groups.

This paper develops an original theory that when individuals deviate from traditional aspects of rituals, they risk signaling a lack of commitment or cultural competence to the group even when such aspects are not explicitly stated.

This study aims to fabricate and manipulate ensemble spin of negative nitrogen-vacancy (NV⁻) centres optimally for future solid atomic magnetometers/gyroscope. Parameters for sample preparation most related to magnetometers/gyroscope are, in particular, the concentration and homogeneity of the NV⁻ centres, the parameters’ microwave antenna of resonance frequency and the strength of the microwave on NV⁻ centres. Besides, the abundance of other impurities such as neutral NV centres (NV⁰) and substitutional nitrogen in the lattice also plays a critical role in magnetic sensing.

The authors succeeded in fabricating the assembly of NV centres in diamond and they determined its concentration of (2-3) × 10¹⁶ cm⁻³ with irradiation followed by annealing under a high temperature condition. They explored a novel magnetic resonance approach to detect the weak magnetic fields that takes advantage of the solid-state electron ensemble spin of NV⁻ centres in diamond. In particular, the authors set up a magnetic sensor on the basis of the assembly of NV centres. They succeeded in fabricating the assembly of NV centres in diamond and determined its concentration. They also clarified the magnetic field intensity measured at different positions along the antenna with different lengths, and they found the optimal position where the signal of the magnetic field reaches the maximum.

The authors mainly reported preparation, initialization, manipulation and measurement of the ensemble spin of the NV centres in diamond using optical excitation and microwave radiation methods with variation of the external magnetic field. They determined the optimal parameters of irradiation and annealing to generate the ensemble NV centres, and a concentration of NV⁻ centres as high as 10¹⁶ cm⁻³ in diamond was obtained. In addition, they found that sensitivity of the magnetometer using this method can reach as low as 5.22 µT/Hz currently.

This research can shed light on the development of an atomic magnetometer and a gyroscope on the basis of the ensemble spin of NV centres in diamond.

High concentration spin of NV⁻ in diamond is one of the advantages compared with that of the atomic vapor cells, because it can obtain a higher concentration. When increasing the spin concentration, the spin signal is easy to detect, and macro-atomic spin magnetometer become possible. This research is the first step for solid atomic magnetometers with high spin density and high sensitivity potentially with further optimization. It has a wide range of applications from fundamental physics tests, sensor applications and navigation to detection of NMR signals.

As has been pointed out, in this research, the authors mainly worked on fabricating NV⁻ centres with high concentration (10¹⁵-10¹⁶ cm⁻³) in diamond by using optimal irradiation and annealing processes, and they quantitatively defined the NV⁻ concentration, which is important for the design of higher concentration processes in the magnetometer and gyroscope. Until now, few groups can directly define the NV⁻ concentration. Besides, the authors optimized the microwave antenna parameters experimentally and explored the dependence between the splitting of the magnetic resonance and the magnetic fields, which dictated the minimum detectable magnetic field.