A New Technical Standard Procedure to Measure stimulation and Gravelpack Fluid Leakoff under Static Conditions

2007 ◽  
Author(s):  
Mahmoud Asadi ◽  
Glenn S. Penny ◽  
Brian Roland Ainley ◽  
David J. Archacki ◽  
Fred van der Bas ◽  
...  
Keyword(s):  
Standard Procedure ◽  
Technical Standard ◽  
Static Conditions

A New Technical Standard Procedure to Measure Stimulation and Gravel-pack Fluid Leak-off under Dynamic Conditions

2015 ◽  
Author(s):  
Mahmoud Asadi ◽  
Brain Ainley ◽  
David Archacki ◽  
Eric Aubry ◽  
Harold Brannon ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Standard Procedure ◽  
Oil And Gas Industry ◽  
Testing Procedure ◽  
Technical Standard ◽  
Gas Wells ◽  
Dynamic Conditions ◽  
Oil And Gas Wells ◽  
Static Conditions ◽  
Gravel Pack

Abstract Historically, leak-off analyses of stimulation fluids have been performed using in-house laboratory procedures. The lack of industry standard procedures to perform leak-off and wall building coefficient analyses of stimulation fluids has introduced inconsistency in both results and reporting for many years. A technical standard adopted in 2006 by both API and ISO for static conditions has provided the oil and gas industry with the first standardized procedure to measure and report leak-off1. However, the more complex testing under dynamic conditions was not addressed. As a result, a group of industry experts have compiled their years of experiences in developing a new technical standard to measure the leak-off characteristics of stimulation and gravel-pack fluids under dynamic flow conditions. Stimulation and gravel-pack fluids are defined, for the purpose of this technical standard, as fluids used to enhance production from oil and gas wells by fracturing and fluids used to place filtration media to control formation sand production from oil and gas wells. Leak-off is the amount of fluid lost to porous media during these operations. The leak-off procedure was developed through the colaberation of several industry companies by evaluating numerous in-house laboratory techniques and conducting round robin testing to ensure that any modifications to these procedures were reliable and repeatable. The new standard provides a step-by-step procedure that includes fluid preparation, experimental equipment design, testing procedure and data analyses for fluids exhibiting viscosity controlled leak-off or wall building characteristics. Example calculations are reviewed within this paper.

A New Technical Standard Procedure To Measure Stimulation and Gravel-Pack Fluid Leak-Off Under Dynamic Conditions

2015 ◽  
Author(s):  
Mahmoud Asadi ◽  
Brian Ainley ◽  
David Archacki ◽  
Eric Aubry ◽  
Harold Dean Brannon ◽  
...  
Keyword(s):  
Standard Procedure ◽  
Technical Standard ◽  
Dynamic Conditions ◽  
Fluid Leak ◽  
Gravel Pack

A New Technical Standard Procedure to Measure Stimulation and Gravel-pack Fluid Leak-off under Dynamic Conditions

2015 ◽  
Author(s):  
Mahmoud Asadi ◽  
Brian Ainley ◽  
David Archacki ◽  
Eric Aubry ◽  
Harold Brannon ◽  
...  
Keyword(s):  
Standard Procedure ◽  
Technical Standard ◽  
Dynamic Conditions ◽  
Fluid Leak ◽  
Gravel Pack

Evolution of the microstructure of Cu(Ti)/SiO2 layers annealed in NH3

1995 ◽  
Vol 53 ◽  
pp. 452-453
Author(s):  
J. Liu ◽  
N. D. Theodore ◽  
D. Adams ◽  
S. Russell ◽  
T. L. Alford ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Titanium Nitride ◽  
Large Scale ◽  
Standard Procedure ◽  
Alloy Film ◽  
Electron Beam Evaporation ◽  
Copper Metallization ◽  
Nominal Composition ◽  
Ti Alloy ◽  
Thermally Grown

Copper-based metallization has recently attracted extensive research because of its potential application in ultra-large-scale integration (ULSI) of semiconductor devices. The feasibility of copper metallization is, however, limited due to its thermal stability issues. In order to utilize copper in metallization systems diffusion barriers such as titanium nitride and other refractory materials, have been employed to enhance the thermal stability of copper. Titanium nitride layers can be formed by annealing Cu(Ti) alloy film evaporated on thermally grown SiO2 substrates in an ammonia ambient. We report here the microstructural evolution of Cu(Ti)/SiO2 layers during annealing in NH3 flowing ambient.The Cu(Ti) films used in this experiment were prepared by electron beam evaporation onto thermally grown SiO2 substrates. The nominal composition of the Cu(Ti) alloy was Cu73Ti27. Thermal treatments were conducted in NH3 flowing ambient for 30 minutes at temperatures ranging from 450°C to 650°C. Cross-section TEM specimens were prepared by the standard procedure.

Are HOLZ lines kinematic in off-zone-axis orientation?

1993 ◽  
Vol 51 ◽  
pp. 692-693
Author(s):  
J. M. Zuo ◽  
A. L. Weickenmeier ◽  
R. Holmestad ◽  
J. C. H. Spence
Keyword(s):  
Structure Determination ◽  
Standard Procedure ◽  
High Order ◽  
Zone Axis ◽  
Great Promise ◽  
Line Position ◽  
Measured Intensity ◽  
Constant Intensity ◽  
Axis Orientation ◽  
Diffraction Condition

The application of high order reflections in a weak diffraction condition off the zone axis center, including those in high order laue zones (HOLZ), holds great promise for structure determination using convergent beam electron diffraction (CBED). It is believed that in this case the intensities of high order reflections are kinematic or two-beam like. Hence, the measured intensity can be related to the structure factor amplitude. Then the standard procedure of structure determination in crystallography may be used for solving unknown structures. The dynamic effect on HOLZ line position and intensity in a strongly diffracting zone axis is well known. In a weak diffraction condition, the HOLZ line position may be approximated by the kinematic position, however, it is not clear whether this is also true for HOLZ intensities. The HOLZ lines, as they appear in CBED patterns, do show strong intensity variations along the line especially near the crossing of two lines, rather than constant intensity along the Bragg condition as predicted by kinematic or two beam theory.

Platelet and Shear Rate Promote Tumor Cell Adhesion to Human Endothelial Extracellular Matrix - Absence of a Role for Platelet Cyclooxygenase

1989 ◽  
Vol 61 (03) ◽  
pp. 485-489 ◽  
Author(s):  
Eva Bastida ◽  
Lourdes Almirall ◽  
Antonio Ordinas
Keyword(s):  
Cell Adhesion ◽  
Shear Rate ◽  
Tumor Cell ◽  
Umbilical Vein ◽  
Blood Platelets ◽  
Flow Conditions ◽  
Tumor Cell Adhesion ◽  
Rate Dependent ◽  
Static Conditions

SummaryBlood platelets are thought to be involved in certain aspects of malignant dissemination. To study the role of platelets in tumor cell adherence to vascular endothelium we performed studies under static and flow conditions, measuring tumor cell adhesion in the absence or presence of platelets. We used highly metastatic human adenocarcinoma cells of the lung, cultured human umbilical vein endothelial cells (ECs) and extracellular matrices (ECM) prepared from confluent EC monolayers. Our results indicated that under static conditions platelets do not significantly increase tumor cell adhesion to either intact ECs or to exposed ECM. Conversely, the studies performed under flow conditions using the flat chamber perfusion system indicated that the presence of 2 × 105 pl/μl in the perfusate significantly increased the number of tumor cells adhered to ECM, and that this effect was shear rate dependent. The maximal values of tumor cell adhesion were obtained, in presence of platelets, at a shear rate of 1,300 sec-1. Furthermore, our results with ASA-treated platelets suggest that the role of platelets in enhancing tumor cell adhesion to ECM is independent of the activation of the platelet cyclooxygenase pathway.

Baboon Fibrinogen Adsorption and Platelet Adhesion to Polymeric Materials

1991 ◽  
Vol 65 (05) ◽  
pp. 608-617 ◽  
Author(s):  
Joseph A Chinn ◽  
Thomas A Horbett ◽  
Buddy D Ratner
Keyword(s):  
Platelet Adhesion ◽  
Coagulation Factor ◽  
Polymeric Materials ◽  
Platelet Suspension ◽  
Perfusion Chamber ◽  
Static Conditions ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Fibrinogen Adsorption

SummaryThe role of fibrinogen in mediating platelet adhesion to polymers exposed to blood plasma was studied by comparison of the effect of plasma dilution on fibrinogen adsorption and platelet adhesion, and by the use of coagulation factor deficient plasmas. Polyetherurethane substrates were first preadsorbed with dilute plasma, then contacted with washed platelets suspended in a modified, apyrase containing Tyrode’s buffer. Platelet adhesion was studied under static conditions in Multiwell dishes, and also under shearing conditions using a parallel plate perfusion chamber. Fibrinogen adsorption and platelet adhesion were measured using 125I radiolabeled baboon fibrinogen and min radiolabeled baboon platelets, respectively. Surfaces were characterized by electron spectroscopy for chemical analysis (ESCA).When fibrinogen adsorption to Biomer was measured after 2 h contact with a series of dilute plasma solutions under static conditions, a peak in adsorption was observed from 0.26% plasma, i.e., adsorption was greater from 0.26% plasma than from either more or less dilute plasma. A peak in subsequent platelet adhesion to the plasma preadsorbed surfaces, measured after 2 h static incubation with washed platelets, was also observed but occurred on Biomer preadsorbed with 1.0% plasma.When fibrinogen adsorption was measured after 5 min contact under shearing conditions, the fibrinogen adsorption peak occurred on surfaces that had been exposed to 1.0% plasma. A peak in platelet adhesion to these preadsorbed surfaces, measured after 5 min contact with the platelet suspensions under shearing conditions, was observed on Biomer preadsorbed with 0.1% plasma. Shifts between the positions of the peaks in protein adsorption and platelet adhesion occurred on other polymers tested as well.Platelet adhesion was almost completely inhibited when baboon and human plasmas lacking fibrinogen (i. e., serum, heat defibrinogenated plasma, and congenitally afibrinogénémie plasma) were used. Platelet adhesion was restored to near normal when exogenous fibrinogen was added to fibrinogen deficient plasmas. Adhesion was also inhibited completely when a monoclonal antibody directed against the glycoprotein IIb/IIIa complex was added to the platelet suspension. Platelet adhesion to surfaces preadsorbed to von Willebrand factor deficient plasma was the same as to surfaces preadsorbed with normal plasma.While it appears that surface bound fibrinogen does mediate the initial attachment of platelets to Biomer, the observation that the fibrinogen adsorption and platelet adhesion maxima do not coincide exactly also suggests that the degree of subsequent platelet adhesion is dictated not only by the amount of surface bound fibrinogen but also by its conformation.

FORMULATION AND DEVELOPMENT OF FAST DISSOLVING TABLET OF METOCLOPRAMIDE: AN ANTI-EMETIC DRUG

2019 ◽  
Vol 8 (6) ◽  
Author(s):  
Avilash Carpenter ◽  
M.K. Gupta ◽  
Neetesh Kumar Jain ◽  
Urvashi Sharma ◽  
Rahul Sisodiya
Keyword(s):  
Mechanical Strength ◽  
Standard Procedure ◽  
Flow Property ◽  
Storage Conditions ◽  
Angle Of Repose ◽  
Dissolution Time ◽  
Disintegration Time ◽  
Powder Blend ◽  
Standard Curve ◽  
The Stability

Aim: The main of the study is to formulate and develop orally disintegrating fast dissolving tablet of Metoclopramide hydrochloride. Material & Methods: Before formulation and development of selected drug, the standard curve in buffer was prepared and absorbance at selected maxima was taken. Then two different disintegrating agents were selected and drug was mixed with disintegrating agents in different ratio. Various Preformulation parameters and evaluation of tablet i.e. disintegration time, dissolution time, friability, hardness, thickness were measured by standard procedure. Result & Discussion: The angle of repose for all the batches prepared. The values were found to be in the range of 30.46 to 36.45, which indicates good flow property for the powder blend according to the USP. The bulk density and tapped density for all the batches varied from 0.49 to 0.54 g/mL and 0.66 to 0.73, respectively. Carr’s index values were found to be in the range of 23.33 to 25.88, which is satisfactory for the powders as well as implies that the blends have good compressibility. Hausner ratio values obtained were in the range of 1.22 to 1.36, which shows a passable flow property for the powder blend based on the USP. The results for tablet thickness and height for all batches was found to range from 4.45 to 4.72 mm and 3.67 to 3.69 mm, respectively. Hardness or breaking force of tablets for all batches was found to range from 32.8 to 36.2 N. Tablet formulations must show good mechanical strength with sufficient hardness in order to handle shipping and transportation. Friability values for all the formulations were found to be in the range of 0.22 % to 0.30 %. Conclusion: Orally disintegrating tablets were compressed in order to have sufficient mechanical strength and integrity to withstand handling, shipping and transportation. The formulation was shown to have a rapid disintegration time that complied with the USP (less than one minute). The data obtained from the stability studies indicated that the orally disintegrating mini-tablets of MTH were stable under different environmental storage conditions. Keywords: Formulation & Development, Fast Dissolving Tablet, Metoclopramide, Anti-Emetic Drug, Oral Disintegrating Tablet

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