Sidewall Material Research Articles

The Distribution Characteristics Analysis of Pollutant Atrazine in the Petrolic Drilling Fluids

In view of the present situation that a lot of waste drilling fluids pollute soil and water in the process of petroleum exploration and development, choosing the drilling fluids in 5 well fields which are in the North area of ChangQing oilfield to carry on the pollution characteristic analysis. 35 physicochemical indexs and contamination indexs had been determined in the drilling fluids, its result is: the waste drilling fluids are ropiness colloid, paste, viscosity high. The drilling fluids ingredient is clay, polyacrylamide (PAM), carboxymethylcellulose (CMC). CODCr, mineral oils, NH4+, Cr, Cd, Pb, As, pH, chromaticity and so on exceed standard in the drilling fluids, Zn exceeds standard in some individual well fields, the other over-standard parameterssuperstandard multiple is not big except CODCr, mineral oils which exceed standard siriously. CODCr, mineral oils, NH4+ and so on are from formation petroleum and the additives such as polyacrylamide (PAM), carboxymethylcellulose (CMC).etc, high pH is related to calcined soda or caustic soda, Cr, Cd, Pb, As, Zn and so on are from the sidewall material which is cattied by the circulating mud, which are related to formation lithological composition.

Thermal Convection and Temperature Inhomogeneity in a Vibrofluidized Granular Bed: The Influence of Sidewall Dissipation

Using a vertically vibrated, fully three-dimensional granular system, we investigate the impact of dissipative interactions between the particles in the system and the vertical sidewalls bounding it. We find that sidewall dissipation influences various properties of the bed including, but not limited to, the spatial distribution of granular temperatures, the functional form of velocity distributions, and the strength of convection. Simple, monotonic relationships are observed for all the aforementioned properties, including a striking linear relationship between convection strength and wall dissipation. We conclude that sidewall effects are not limited to the vicinity of the walls themselves, but extend into the bulk of the system and hence must be considered even in relatively wide, three-dimensional systems. We also propose the possibility of using the alteration of sidewall material as a method of "tuning" certain system parameters in situations where changing the bulk properties or driving parameters of a granular system may be undesirable.

Modelling the vibration of tyre sidewalls

The dynamical behaviour of the sidewall has an important influence on tyre vibration characteristics. Nonetheless, it remains crudely represented in many existing models. The current work considers a geometrically accurate, two-dimensional, sidewall description, with a view to identifying potential shortcomings in the approximate formulations and identifying the physical characteristics that must be accounted for. First, the mean stress state under pressurisation and centrifugal loading is investigated. Finite-Element calculations show that, while the loaded sidewall shape remains close to a toroid, its in-plane tensions differ appreciably from the associated analytical solution. This is largely due to the inability of the anisotropic sidewall material to sustain significant azimuthal stress. An approximate analysis, based on the meridional tension alone, is therefore developed, and shown to yield accurate predictions. In conjunction with a set of formulae for the ‘engineering constants’ of the sidewall material, the approximate solutions provide a straightforward and efficient means of determining the base state for the vibration analysis. The latter is implemented via a ‘waveguide’ discretisation of a variational formulation. Its results show that, while the full geometrical description is necessary for a complete and reliable characterisation of the sidewall's vibrational properties, a one-dimensional approximation will often be satisfactory in practice. Meridional thickness variations only become important at higher frequencies (above 500Hz for the example considered here), and rotational inertia effects appear to be minor at practical vehicle speeds.

Factors Affecting Corrosion Resistance of Silicon Nitride Bonded Silicon Carbide Refractory Blocks

The lifetime of aluminum reduction cells is driven primarily by the lifetimes of two components of the cell lining: the carbon cathode and the sidewall refractory material. The current state‐of‐the‐art sidewall material is a silicon nitride bonded silicon carbide (SNBSC) refractory and its corrosion mechanisms in the aluminum reduction cell environment have been examined in this study. Microstructural analysis of commercial SNBSC materials identified variations in porosity and α/β Si3N4 ratio in the binder phase, with higher porosity levels and β Si3N4 content found in the interior part of the block. Unreacted metallic silicon was observed only as a crystalline phase encapsulated inside SiC grains and not in the binder phase. The effects on the corrosion rate of porosity levels, amount of binder, α/β Si3N4 ratio, and different factors in the environment, were examined in laboratory scale trials. High corrosion rates were associated with high porosity levels and a high β Si3N4 fraction in the binder. The crystal morphology of β Si3N4 is suggested as the main reason for the higher reactivity of this material. This morphology presents a higher surface area compared with α Si3N4 crystals. A corrosion mechanism for SNBSC materials in the aluminum reduction cell atmosphere is suggested.

Closed form calculation of reverberant sound propagation in a thin duct with flexible walls.

An analytical method for calculating the propagation of reverberant sound between two parallel perfectly reflecting planes in a thin duct with flexible side walls is presented. The flexible walls are modeled with a complex wave number to account for dissipation within the wall material. A mathematical model based on the Euler–Maclaurin sum formula provides an approximate closed form Green’s function for the acoustic space. The method gives a set of two coupled integral equations in acoustic pressure and side wall displacement consisting of convolutions with respect to the spatial dimension along the duct. Laplace transforms for the spatial dimension are applied to the integral equations to solve for the acoustic pressure in terms of the spatial Laplace transforms of the Green functions for the reverberant acoustic space and the mechanical wave in the side wall material. A closed form solution is obtained by considering the first term of a binomial series in the Laplace domain and applying a partial fraction expansion leading to the solution in the spatial dimension along the duct. Numerical simulations show the behavior of the reverberant noise reduction provided by the flexible side walls along the duct.

A Cost Effective Spin on Sidewall Material Alternative to the CVD Sidewall Process

193nm immersion and Hyper NA lithography are used at 45nm and beyond. The next generation of lithography will use a new technology such as Double Pattering, EUV or EB. Double patterning is one of the currently acceptable technologies. Three common double pattern techniques are Litho-Etch-Litho-Etch (LELE), freezing, and sidewall (spacer) process. From a technical standpoint LELE is a very promising process, except for the second litho alignment. However, the cost of ownership will be very high because LELE will cost about twice as much as the current single litho patterning process. In order to build up a suitable double patterning technique, many device makers are developing unique processes. Two of these processes are freezing and sidewall. Flash memory makers are diligently investigating the sidewall process by CVD. This is because of the lack of a second litho alignment step, even with its high cost. The high cost of the CVD process can be reduced if a spin on material is used. One of the goals of this paper is to reduce the cost of ownership by using spin on coatings for the sidewall process. Currently we are investigating this approach to control the sidewall width, profile and other properties.

Coupled temperature–displacement modelling of injection stretch-blow moulding of PET bottles using Buckley model

This study presents a fully coupled temperature–displacement finite element modelling of the injection stretch-blow moulding (ISBM) process of polyethylene terephthalate (PET) bottles using ABAQUS with a view to optimising the process conditions. A physically-based material model (Buckley model) was used to predict the mechanical behaviour of PET at temperatures slightly above its glass transition temperature. A model incorporating heat transfer between the stretch rod, the preform and the mould was built using axisymmetric solid elements. Extensive finite element analyses were carried out to predict the deformation, the distribution and history of strain and temperature during ISBM of a 20g–330ml bottle, which was made in an in situ test on a Sidel SB06 machine. Comparisons of numerical results with the measurements demonstrate that the model can satisfactorily model the sidewall thickness and material distributions. It is also shown that significant non-linear differentials exist in temperature and strain in both bottle thickness and length directions during the process. This justifies the employment of a volume approach to accurately predict the final mechanical properties of the bottles governed by the orientation and crystallinity which are highly temperature and strain dependent.

Evaluation of Ta and TaN-based Cu diffusion barriers deposited by Advanced Hi-Fill (AHF) sputtering onto blanket wafers and high aspect ratio structures

This paper investigates the properties of Ta and Ta(N) barrier layers deposited by Advanced Hi-Fill ® (AHF) sputtering onto both blanket and patterned wafers. The differences, in terms of forming an effective diffusion barrier, between Ta and Ta(N) barriers of varying N 2 content and the important integration issues that are brought about by the comparison of blanket and patterned wafers are emphasised. In particular, from the blanket study we find that Ta(N) films with high N 2 content form the best diffusion barriers to Cu, while the study on patterned wafers indicates that an intermediate N 2 flow consistent with a blanket deposition of mixed phase b.c.c. and β Ta forms the optimum barrier in terms of maximised sidewall coverage and material quality.

Dopant Effects on Lateral Silicide Growth in Self‐Aligned Titanium Silicide Process

The effects of sidewall material and implanted dopants have been investigated on the lateral silicide growth in self‐aligned titanium silicide process. The sidewall spacer showed no lateral silicide growth and has a low leakage current between gate and source/drain up to silicidation temperatures of 750°C. This was found to be due to released oxygen from the sidewall spacer into titanium film, which impedes silicon diffusion over the . However, the sidewall spacer showed dopant dependence of the lateral silicide growth and leakage current. This discrepancy between and results from the fact that nitrogen has lower reactivity with titanium and less suppression of the lateral silicide growth than oxygen. The lateral silicide growth and leakage current in decreased in the order of dopant species of and P. Released dopants from can affect the silicon diffusion, and this is closely related to the reactivity of each dopant with titanium.

Predicting Gas, Oil, and Water Intervals in Niger Delta Reservoirs Using Gas Chromatography

Formation evaluation experts usually have little difficulty in interpreting wireline logs to assess the type of reservoir fluid (oil/gas/water) in sand-shale sequences. This assessment is usually accomplished by a combination neutron-density tool that detects low hydrogen and low electron densities typical of gas zones, and the repeat formation tester (RFT), which uses both the pressure gradient and sample acquisition techniques to evaluate reservoir fluid. In the Niger Delta, however, many of the sands exhibit a poor neutron-density response to gas, and RFT testing has been largely eliminated because poor hole conditions commonly result in stuck tools. Oil fingerprinting of residual hydrocarbons from sidewall core extracts can provide an independent means of identifying eservoir fluid type. In conjunction with the Nigerian National Petroleum Company, we completed numerous chromatographic analyses on solvent extracts of sidewall core samples from various wells in the Mefa field, offshore west Niger Delta. Oil fingerprints of sidewall core extracts clearly reflect the type of hydrocarbons in the reservoir. Fingerprints of oil-saturated sands are typical of topped (C15+) whole oils, whereas fingerprints of hydrocarbons extracted from the gas-dominated sands show an abbreviated hydrocarbon distribution more typical of gas condensates. Fingerprints of extracts from water-productive intervals show a further abbreviated signature, suggesting that higher molecular weight hydrocarbons did not migrate into these intervals. These signatures are distinct and intact despit poor sample preservation due to prolonged storage of up to 3 yr. Additional applications of this technique include the reevaluation of older wells that lack modern wireline measurements, but have sidewall or conventional core material available, and in thin or low-permeability sands that may not yield definitive RFT or wireline-log responses. Application potential for this technology is worldwide and includes the Gulf Coast of the United States, Canada, Indonesia, and Papua New Guinea.

Electrical characterization of GaAs PiN junction diodes grown in trenches by atomic layer epitaxy

We report the electrical characterization of GaAs PiN junction diodes grown over the sidewalls of patterned trenches by atomic layer epitaxy. The diodes exhibit excellent rectifying behavior demonstrating that high quality GaAs was grown on the entire trench structure including sidewalls and corners. The sidewall material is characterized electrically through reverse bias diode leakage from thermal generation in the depletion region. 2-μm-deep trenches contribute a leakage current of less than 60 μA/cm2 of sidewall area under 1 V reverse bias at 144 °C, which is satisfactory for most device applications.

Experimental tire mechanics by moiré

Tires and their component parts are made from various low modulus rubbers and cord/rubber laminates. In service they typically undergo large deformations of about 1–30%. The accurate measurement of these deformations by either pointwise (strain gage) or full-field (optical) techniques is rendered difficult in these circumstances. Ordinary strain gages reinforce these soft structures and inhibit their deformation, whereas most optical methods are too sensitive to measure large motions. These difficulties can be overcome by the judicious use of various moiré methods: moiré interferometry, geometric moiré and shadow moiré. Several applications of moiré methods to tire mechanics problems are presented. The emphasis is on the range of problems that has been successfully approached and on the results obtained. Examples are drawn from work on belt-edge strains, tread groove strains, sidewall strains, dynamic sidewall deformations and material properties determination. Proprietary details of technique are not included.

An Advanced Solution: The Drilling Adviser

Summary This paper discusses the Drilling Advisor, a computer-based consultant whose goal is to provide advice about the cause and possible treatments of problems encountered during the drilling of wells. With the "Expert Systems" technique, a large amount of human knowledge can be represented as data structures in the system and efficiently used to make conclusions about the problem. Currently, the system handles sticking and dragging of the drillstring in the open hole. Introduction Artificial intelligence is the part of computer science concerned with designing intelligent computer systems. Recently, the field of Expert Systems, or "knowledge engineering, has emerged from this large research area and proved to be useful in some applications. (The MYCIN project-whose goal is to diagnose a bacterial infection project-whose goal is to diagnose a bacterial infection and recommend the best therapy-is one of these. ) Typically, Expert Systems can be viewed as intermediaries between human experts-who interact with the system in a "knowledge-acquisition" mode (adding new knowledge into the system, usually in the form of "if/then" rules)-and human users-who interact in a "consultation" mode. Furthermore. these systems have the capacity to explain their reasoning, which makes the consultation more acceptable and helps the human expert find errors or missing knowledge. Drilling is a domain for which experience is very important. Until now it was quite impossible to acquire this kind of knowledge from field experts and make it available for use by new engineers. Expert Systems addresses this difficulty directly, allowing expertise to be represented within the system and thereby making it usable on drilling sites to help solve problems. The system assists the driller and helps him make decisions in all kinds of situations, which leads to more efficient drilling and to saving money by saving time. Having the experience and the rules of art encoded in a machine can also be very useful for training purposes. The conservation and communication of the know-how and experience accumulated by our technicians as a result of their daily operations is already a permanent objective. and here knowledge is a key resource. For all these reasons, Soc. Natl. Elf Aquitaine and Teknowledge Inc. have jointly undertaken to build an expert system, first called the Drilling Advisor, then SECOFOR. The system currently handles both dragging and sticking incidents, but most of the knowledge already entered in the system could be used to handle other types of incidents as well. For each problem submitted, SECOFOR provides two types of advice:a diagnosis indicating the most likely cause(s) of the problem with a set of reasons supporting its conclusions, anda set of treatment recommendations aimed at solving the current problem and preventing its recurrence. preventing its recurrence. Problem Definition Problem Definition We will not explain how a drillstring gets stuck. We will consider only those problems that happen in the open hole-between the casing shoe and the total depth (TD)- as a result of some undesirable interaction between the geological formations, the drillstring, and the drilling mud. The diagnosis phase of a SECOFOR consultation gathers evidence and tries to classify the problems as one or more of three main causes of sticking or dragging. Differential Pressure. In conditions of differential pressure (DP), the mud's specific gravity exceeds the pressure (DP), the mud's specific gravity exceeds the equivalent gravity of the fluids in some permeable formation of the open hole. The sticking may occur if some smooth element of the bottomhole assembly (BHA) or the drillpipe comes into motionless contact with the cake left by the mud on the sidewall. The pressure gradient inside the cake generates a strong "sticking force," even for thin cakes. This is the most frequent cause of all sticking cases. Annulus Plug. This cause of sticking is a direct result of some characteristics of the formations in the open hole. it has been subdivided into three individual causes, all of which result in the annular space being completely plugged by materials from the formation. Sloughing. Sloughing is the result of sidewall material falling into the well (e.g., foliated shales or disaggregated rock break up when the mud and the hydraulic parameters are inadequate). parameters are inadequate). Balling Up. Balling up happens when the cleaning effect of mud circulation on the annulus is unsatisfactory (e.g., bad viscosity, low flow rate, and gumbos). Tight Hole. Tight hole is caused by creeping or swelling formations closing in on the drillstring, thus trapping it (e.g., salt). JPT p. 899

Fluence perturbation in photon beams under nonequilibrium conditions

The perturbation effect in parallel-plate ionization chambers used for buildup measurements has been investigated. The fluence perturbation due to electrons emitted through the side walls are thoroughly investigated by measurements using film and extrapolation chambers and by calculations. The electron fluence varies both with side wall material and chamber geometry. In order to obtain a small perturbation effect, the chamber should have a large guard width compared to the electrode separation and the side walls should have as large an angle as possible with the central axis. The side wall should be of the same material as the rest of the chamber. The perturbation effect is also dependent on the electron contamination of the beam and angular distribution of the electron fluence. It is thus not possible to correct the perturbation effect in one parallel-plate chamber with fixed plate separation with correction factors obtained with extrapolation chambers of other dimensions. In order to make accurate surface dose measurements extrapolation chambers are therefore strongly recommended in favor of fixed parallel-plate chambers.

The structural response of a rail accelerator

The transient response of a 0.4 by 0.6 cm rectangular bore rail accelerator was analyzed using a three-dimensional finite-element code. Results are presented for the case of a 210-kA current input and 5-cm arc length. Typically, the copper rail deflected to a peak value of 0.08 mm in compression and then oscillated at an amplitude of 0.02 mm. Simultaneously the insulating side wall of glass fabric base, epoxy resin laminate (G-10) was compressed to a peak value of 0.13 mm and rebounded to a steady state in extension. Projectile pinch or blow-by due to the rail (or side-wall) extension or compression, respectively, can be identified by examining the time history of the rail (or side-wall) displacement. For the case presented, the effect of blow-by was most significant at the side wall characterized by mm-size displacement in compression. Dynamic stress calculations indicate that the G-10 supporting material behind the rail is subjected to over 21 MPa - at which the G-10 could fail if the laminate was not carefully oriented. Results for a polycarbonate resin (Lexan) side wall show much larger displacements and stresses than for G-10. Therefore the tradeoff between the transparency of Lexan and the mechanical strength of G-10 for side-wall material is obvious. Displacement calculations from the modal method are smaller than the results from the direct integration method by almost an order of nagnitude, because the high-frequency effect is neglected. However, this effect is significant and dominating for a highly-impulsive, wave-propagation problem such as the rail accelerator structure.

Topographical distribution of penicillin-binding proteins in the Escherichia coli membrane.

The penicillin-binding proteins (PBPs) found in the membranes of Escherichia coli X925 minicells (primarily cell ends or septa) were compared with those found in rod-shaped cells (primarily sidewalls) in an effort to determine whether certain PBPs are unevenly distributed over the bacterial cell membrane. The seven major PBPs of E. coli were all present in minicell membranes. PBP 1B was altered in minicells, however, appearing as two bands on sodium dodecyl sulfate-polyacrylamide gels rather than the usual three. PBP 2, which is needed for longitudinal growth of the cell but not for septum formation, was significantly reduced in minicell membranes. This observation is consistent with the fact that minicells contain very little sidewall material and raises the possibility that the specialized function of PBP 2 may be determined or regulated by its uneven topographical distribution in the membrane. None of the PBPs appeared to be selectively enriched in minicell membranes.

Sidewall Induced Boresite Error in an Anechoic Chamber

An anechoic chamber used for missile test or simulation inherently adds boresite error, generally as a result of sidewall reflections. A simple method of analysis shows this error depends on the sidewall angle of arrival through the antenna difference pattern and the bistatic reflection coefficient of the sidewall material. This material coefficient which is seldom measured is of critical importance.