bluuebunny/crossref_metadata_2025 huggingface dataset:
THREATS TO U.S. CONTROL OF MIDDLE EASTERN OIL
Authors: Aijaz Ahmad Wani
Published: August 2023

Since the discovery of oil wealth in the region of Middle East it became the battle ground for great States to compete on. Particularly after the world war 2ndtill this date the great states like Britain, France, Russia and China are early watching the chessboard to manipulate an opportunity in their favour. It is this competition over the oil of Middle East which has left the control of America both insecure and competitive.
Xác định độ chính xác trọng lực của mô hình trường trọng lực toàn cầu SGG-UGM-2 khu vực miền Nam Việt Nam.
Authors: Bùi Thị Hồng Thắm , Đỗ Thị Hoài
Published: August 2023

Độ chính xác của mô hình trường trọng lực toàn cầu SGG-UGM-2 được xác định dựa trên số liệu trọng lực đo đạc chi tiết tại khu vực miền Nam, Việt Nam theo một quy trình chặt chẽ và rõ ràng. Số liệu trọng lực đo đạc chi tiết được chuẩn hóa về hệ triều không, đây cũng là hệ triều của số liệu trọng lực khai thác từ mô hình trường trọng lực toàn cầu SGG-UGM-2. Quá trình tính toán cho thấy, trong số 1540 điểm trọng lực tại khu vực thực nghiệm, có 16 điểm (tương đương với khoảng 1% tổng số điểm) không đạt chất lượng nên bị loại bỏ, 1524 điểm trọng lực có chất lượng đạt yêu cầu tham gia vào việc xác định độ chính xác mô hình trường trọng lực toàn cầu SGG-UGM-2. Kết quả cho thấy, mô hình trường trọng lực toàn cầu SGG-UGM-2 có độ chính xác là ±4,762 mgal. Đây là nguồn thông tin hữu ích cho các nhà khoa học và các nhà quản lý khi sử dụng mô hình này tại khu vực thực nghiệm. Các bước xác định độ chính xác của mô hình trường trọng lực toàn cầu trong nghiên cứu này hoàn toàn có thể áp dụng đối với các mô hình và các vùng nghiên cứu khác.
Evaluation of pig pneumonia at slaughter using polymerase chain reaction and histopathology in Argentina
Authors: Cappuccio Javier , Dibarbora Marina , Bessone Fernando , Olivera Valeria , Lozada Ines , Alustiza Fabrisio , Quiroga Alejandra , Perez Estefania , Zielinski Gustavo , Perfumo Carlos , Pereda Ariel , Perez Daniel
Published: August 2023

Histopathology and polymerase chain reaction were conducted on 81 lungs collected at slaughter from 13 swine farms free of porcine reproductive and respiratory syndrome virus and pseudorabies virus infection. Pasteurella multocida and Mycoplasma hyopneumoniae were the most common pathogens detected. Suppurative and catarrhal bronchopneumonia was present in 59 (72.8%) cases.
Free Exchange is Not Free
Authors: Brown Aaron
Published: August 2023

The rise of crypto markets and smart contracts has fueled innovation in exchange mechanisms. This article explores core market design principles and their tradeoffs.
Using QuantLib Interactively
Authors: Ballabio Luigi
Published: August 2023

The joys of quick feedback.
Stochastic Differential Equations in Finance
Authors: Kelly Andrei
Published: August 2023

Harnessing the power of Mathematica and the Wolfram language for stochastic or probabilistic models
Potential Future Exposure of Target Redemption Forwards
Authors: Renzitti Stefano
Published: August 2023

We calculate the PFE of TARFs using both a smile aware Heston model and a smile unaware Garman-Kohlhagen (GK) model. Results show that the FX Heston model tends to produce significantly different PFEs than the GK model, highlighting the importance for a dealer's global simulation model to accurately capture 1) the distribution of the underlying spot rate, and 2) the joint distribution of the underlying and its implied volatility surface.
Nursing model of midwifery and postural and psychological interventions: Impact on maternal and fetal outcomes and negative emotions of primiparas
Authors: Gao Ping , Guo Cai-Qiong , Chen Ma-Yu , Zhuang Hui-Ping
Published: August 2023

Rapid-cycling bipolar disorder (RCBD) is a phase of bipolar disorder defined by the presence of ≥ 4 mood episodes in a year. It is a common phenomenon characterized by greater severity, a predominance of depression, higher levels of disability, and poorer overall outcomes. It is resistant to treatment by conventional pharmacotherapy. The existing literature underlines the scarcity of evidence and the gaps in knowledge about the optimal treatment strategies for RCBD. However, most reviews have considered only pharmacological treatment options for RCBD. Given the treatment-refractory nature of RCBD, nonpharmacological interventions could augment medications but have not been adequately examined. This review carried out an updated and comprehensive search for evidence regarding the role of nonpharmacological therapies as adjuncts to medications in RCBD. We identified 83 reviews and meta-analyses concerning the treatment of RCBD. Additionally, we found 42 reports on adjunctive nonpharmacological treatments in RCBD. Most of the evidence favoured concomitant electroconvulsive therapy as an acute and maintenance treatment. There was preliminary evidence to suggest that chronotherapeutic treatments can provide better outcomes when combined with medications. The research on adjunctive psychotherapy was particularly scarce but suggested that psychoeducation, cognitive behavioural therapy, family interventions, and supportive psychotherapy may be helpful. The overall quality of evidence was poor and suffered from several methodological shortcomings. There is a need for more methodologically sound research in this area, although clinicians can use the existing evidence to select and individualize nonpharmacological treatment options for better management of RCBD. Patient summaries are included to highlight some of the issues concerning the implementation of adjunctive nonpharmacological treatments.
PENGARUH LITERASI DIGITAL DAN KONFORMITAS TERHADAP MINAT TECHNOPRENEURSHIP MAHASISWA
Authors: Perdana Rahmadi Nanda Putra , Sadiah Ati , Kurniawan
Published: August 2023

This study addresses students' limited interest in technopreneurship and examines the impact of Digital Literacy and Conformity on Technopreneurship Interest. Using a quantitative survey approach with an explanatory design, the research involves 104 Economics Education students from Universitas Siliwangi (2019 cohort). Employing saturated sampling, data collection utilizes questionnaires and analysis includes multiple linear regression with t-test and F-test. Findings reveal high levels of Technopreneurship Interest (7.996), Digital Literacy (7.681), and Conformity (5.543). Digital Literacy significantly positively influences Technopreneurship Interest (p < 0.05), as does Conformity (p < 0.05). Simultaneously, Digital Literacy and Conformity collectively impact students' Technopreneurship Interest significantly (p < 0.05, coefficient of determination 60.9%). These outcomes emphasize the influential role of Digital Literacy and Conformity in shaping students' interest in technopreneurship.
Nghiên cứu khả năng cảm ứng phytohormone và biểu hiện đặc thù của nhóm gene mã hóa enzyme trehalose-6-phosphate phosphatase ở cây Sắn (Manihot esculenta)
Authors: Hạnh Phạm Mỹ , Trung Vũ Minh , Tiến Trần Văn , Hương Bùi Thị Thu , Trung Nguyễn Quốc , Quyến Hà Thị , Thuỳ Phạm Châu , Quỳnh Lê Thị Ngọc , Hà Chu Đức
Published: August 2023

Trehalose-6-phosphate phosphatase (TPP) được ghi nhận là enzyme chính tham gia vào quá trình sinh tổng hợp trehalose. Nghiên cứu trước đây đã ghi nhận vai trò của nhóm TPP liên quan đến các quá trình sinh học diễn ra ở thực vật. Trong nghiên cứu này, tổng số 10 thành viên của nhóm TPP đã được báo cáo trong dữ liệu của cây sắn (Manihot esculenta). Thông tin chú giải và vị trí phân bố trên nhiễm sắc thể của nhóm MeTPP đã được khai thác. Các gene thành viên MeTPP phân bố rải rác trên nhiễm sắc thể trong genome của cây sắn. Cụ thể, nhiễm sắc thể số 2, 6 và 14 chứa 2 gene MeTPP. Khảo sát vùng promoter của nhóm gene MeTPP đã phát hiện sự phân bố của các nhóm yếu tố điều hòa cis- cảm ứng phytohormone. Nghiên cứu đã xác định được promoter của 8 gene MeTPP chứa ít nhất một nhóm yếu tố điều hòa cis- cảm ứng với auxin, ethylene, abscisic acid, salicylic acid, jasmonic acid và gibberellin. Phân tích dữ liệu RNA-Seq cho thấy 7 gene MeTPP có biểu hiện ở ít nhất 1 mẫu. MeTPP09 được xác định là gene có biểu hiện đặc thù ở lá và gân lá, biểu hiện mạnh ở thân, tổ chức phát sinh phôi cấu tạo soma và mô phân sinh chóp rễ, trong khi MeTPP03 và 05 có xu hướng biểu hiện mạnh ở mô sẹo phôi hóa. Kết quả của nghiên cứu này đã cung cấp những thông tin cơ bản về nhóm enzyme TPP ở cây sắn để phân tích chức năng gene MeTPP liên quan đến tính chống chịu.
Đánh giá thực trạng và đề xuất giải pháp về chiến thuật chữa cháy trên mặt đất cho rừng thông ở huyện Sóc Sơn, thành phố Hà Nội
Authors: Khánh Trần Kim , Quỳnh Vương Văn , Xiêm Ngô Văn
Published: August 2023

Rừng thông ở huyện Sóc Sơn là loại có nguy cơ cháy cao, đặc biệt vào mùa khô và nắng nóng. Do vậy, mục tiêu của bài báo này nhằm đánh giá thực trạng và đề xuất giải pháp về chiến thuật chữa cháy trên mặt đất cho rừng thông ở huyện Sóc Sơn, thành phố Hà Nội. Nhóm tác giả cũng đã tổ chức khảo sát thực địa để nắm tổng quát về hiện trạng tài nguyên rừng, tình hình sử dụng đất, tình hình sử dụng rừng, tình hình giao đất, giao rừng... Bài báo đã cung cấp kết quả nghiên cứu về những đặc điểm công tác chữa cháy rừng thông ở huyện Sóc Sơn, bao gồm những ưu điểm như: sự chủ động về lực lượng, thường xuyên tập luyện về nghiệp vụ, định kỳ bảo dưỡng và thường xuyên trang bị bổ sung phương tiện, kinh nghiệm chữa cháy rừng được tích lũy nhiều năm. Công tác chữa cháy vẫn còn tồn tại các nhược điểm như thiếu hệ thống cảnh báo phát hiện sớm cháy rừng, thiếu phương án chữa cháy rừng, thiếu phương tiện chữa cháy hiệu quả, thiếu bảo hộ lao động thích hợp với chữa cháy rừng, chiến thuật chữa cháy rừng chưa hợp lý, kỹ thuật chữa cháy chưa được hoàn chỉnh. Các giải pháp nâng cao hiệu quả phòng cháy chữa cháy rừng như tăng cường khai thác phương tiện, giải pháp về phương pháp chữa cháy, giải pháp cụ thể khác về chiến thuật chữa cháy và kỹ thuật chữa cháy.
Đánh giá thực trạng và đề xuất giải pháp nâng cao chất lượng hoạt động của chi nhánh Văn phòng Đăng ký đất đai huyện Sông Mã, tỉnh Sơn La
Authors: Hiếu Phạm Trung , Quế Phạm Thanh , Nga Vũ Thị Quỳnh
Published: August 2023

Nghiên cứu thực hiện nhằm mục đích đánh giá thực trạng và đề xuất giải pháp nâng cao chất lượng hoạt động của chi nhánh Văn phòng Đăng ký đất đai (CNVPĐKĐĐ) huyện Sông Mã. Giai đoạn 2019 - 2021, CNVPĐKĐĐ đã tập trung thực hiện các nhiệm vụ và đạt được các kết quả: đăng ký đất đai ban đầu (293 trường hợp), đăng ký biến động đất đai (2337 trường hợp), cập nhật chỉnh lý biến động đất đai (1971 trường hợp), cấp giấy chứng nhận quyền sử dụng đất (6606 trường hợp), cung cấp thông tin đất đai (780 trường hợp) và đăng ký biện pháp đảm bảo (6009 trường hợp). Kết quả đánh giá sự hài lòng của người dân và cán bộ cho thấy hoạt động của CNPĐKĐĐ huyện Sông Mã đều ở mức hài lòng. Tuy nhiên, vẫn còn một tỷ lệ nhỏ người sử dụng đất chưa hài lòng về nơi thực hiện chưa đủ chỗ ngồi chờ (1,7%), trang thiết bị thực hiện chưa dễ sử dụng (2,5%), phí và lệ phí còn cao (1,7%), thời gian giải quyết thủ tục hành chính (3,3%). Đối với số lượng cán bộ và cơ sở vật chất của chi nhánh đa phần người đánh giá đều cho rằng cần phải bổ sung thêm. Để khắc phục những vấn đề tồn tại, bất cập trong hoạt động của CNVPĐKĐĐ huyện Sông Mã, cần thực hiện đồng bộ các nhóm giải pháp gồm: giải pháp về con người, nguồn nhân lực; giải pháp về tổ chức, cơ chế hoạt động; giải pháp về cơ sở vật chất kỹ thuật; giải pháp về cơ chế phối hợp giữa các cơ quan.
Thực trạng công tác định giá đất ở tại thành phố Từ Sơn, tỉnh Bắc Ninh
Authors: Huệ Nguyễn Thị , Huyền Phan Thị Thanh , Quân Nguyễn Văn
Published: August 2023

Nghiên cứu nhằm chỉ ra những ưu điểm, hạn chế và nguyên nhân trong công tác định giá đất ở cụ thể tại thành phố Từ Sơn. Kết quả nghiên cứu cho thấy, ngoài ưu điểm như nhận được sự quan tâm của các cấp lãnh đạo, đánh giá ở mức 1; cơ sở vật chất, trang thiết bị tương đối đầy đủ với điểm đánh giá tương ứng là 4,30 và 3,65; nguyên tắc, phương pháp định giá đất khá rõ ràng với điểm tương ứng là 3,47 và 3,13 thì vẫn còn những hạn chế như giá đất trong khung, bảng giá đất chưa phù hợp, không phản ánh đúng giá đất ở thị trường, giá đất ở thị trường thu thập được ít tin cậy, với điểm tương ứng là 1,77, 1,50 và 1,97; nhân lực định giá đất chưa đáp ứng cả về số lượng và chất lượng, điểm đánh giá 2,3; quy trình, thủ tục phức tạp, điểm đánh giá là 2,47 điểm. Kinh phí đầu tư cho định giá đất ở chưa có nên điểm đánh giá chỉ đạt 1,93 điểm. Để giải quyết những hạn chế, tồn tại trên cần áp dụng đồng thời 5 giải pháp về xây dựng cơ sở dữ liệu; nhân lực định giá đất; kiện toàn vai trò, chức năng của các tổ chức định giá đất; xây dựng và phát triển hệ thống định giá đất chuyên nghiệp; đảm bảo kinh phí định giá đất.
PR-244-114510-R01 Support for Standardization of Weld Testing Methods - Curved Wide Plate Testing
Authors: Stephens Mark
Published: August 2023

This work (1) performed a literature review of existing test procedure and protocols, (2) an associated workshop to evaluate subject matter experts of the key element of the Recommended Practice and a discussion of the Technical issues, and (3) prepare a Recommended Practice.
L52332 Offshore Pipeline Damage Emergency Response Guidelines
Authors: Ayers  , Dotson  , Alexander
Published: August 2023

Subsea pipelines and flow lines are periodically subjected to damaging events such as anchor impacts that result in massive pipeline movements, dropped object damage, internal/external corrosion damage, etc. Knowing how to assess these damage events is often challenging, especially considering the potential for product release. The cost of production shut-ins can be significant and avoiding un-necessary shut-ins is desirable. While most pipeline operators have company-level procedures and programs in place for responding to pipeline emergencies, at the current time there is no single resource for providing guidance for the pipeline industry.

Development of emergency response guidelines for operators to respond to offshore pipeline damage emergencies in an effective and timely manner. One unique feature of this project is that SES utilized a series of workshops spaced over a years to collectively build the Decision/Task Tree, which is the key feature of this work. Further, a collaborative effort was continued to develop detailed input for the report. This Collaborative Workshop Model of conducting project work combines the best minds available on the subject, rather than having our customers merely serve as observers and evaluators, as is done traditionally. A second unique feature is that this report is formatted as a computer-based entry portal a "front door"� to existing proprietary documents that each company has assembled for use in responding to an offshore pipeline damage incident. Often the treasured company documents are in dusty notebooks that should be scanned for incorporation with this front door document. This guideline document in its final form can provide live links to the proprietary company documents in an Adobe Acrobat format, along with the materials we have developed for the project. This front door is intended for use on a computer that is linked to the internet. The contents of this report are organized to place traditional introductory topics that would detract from operational use of this report for actual offshore emergencies in appendices near the back of the report.

This report provides insights on the critical elements required for effectively responding to pipeline emergencies. PART A of this report contains the traditional introductory material, while PART B is named the Field Manual - for offshore emergency use. PART B can be used alone as an emergency response field manual without the introductory material PART A contains the Executive Summary, Introduction and Background, while PART B Contains the Preface to the Field Manual, How to Use This Report, the Detailed Task/Decision Matrix, the Resource Sheets referred to in the Matrix, In-House Company Processes Needed, Table of Preferred Consultants and Service Providers, and the SPIM 3-1 Detailed Repair Investigation Checklist.
PR-015-084508-R01 Contaminants in Sales Gas Pipelines Sources Removal and Treatment
Authors: Baldwin Richard
Published: August 2023

The objective of this project is to provide information about a problem material found in gas pipelines called "black powder". It is a mixture or a chemical compound of iron sulfides, iron oxides, dirt, sand, salts, chlorides, water, glycols, hydrocarbons and compressor oils, mill scale, or other materials. The most common constituents, iron compounds of sulfur or oxygen, are corrosion products. In addition to chemical formation, black powder can be formed by microbes normally found in gas pipelines. This material causes machinery, measurement, and pipeline maintenance problems. This research investigates the forms of iron sulfides, their characteristics, and methods of formation and whether the molecular form can be an indicator of the source of the material. A sampling protocol was developed for proper collection of materials for analysis. Seventeen corrosion samples were collected and analyzed for material constituents and microbial content. The results of this testing were anonymously tabulated in a database. Other tasks in this project include guidelines for removal, handling, and disposal of the material. It discusses symptomatic versus root cause treatments for the prevention and control of black powder, and the corporate culture necessary to manage the problem. It presents recently developed technologies for cleaning or treating a pipeline containing black powder, such as cleaning and anti-microbial agents containing THPS which dissolve iron sulfides, and the use of magnetic filtration. The final task describes concepts for identifying the location of black powder in an operating pipeline and places to look and methods to use to best determine the distribution of the material.
L19720 Preliminary Stray-Current Tests HVDC Power Transmission The Dalles - Los Angeles
Authors: Unknown Author
Published: August 2023

The goal of this research was to determine the effects on buried structures of stray current flow resulting from operation of the Pacific-NW-SW DC intertie. The intertie runs from The Dalles, Oregon to Los Angeles, California, approximately 850 miles. Preliminary tests were conducted from June 2 to July 15, 1969. The goal of these tests was to prepare for full-scale tests to be conducted in 1970.It was observed from the preliminary tests that when using 300 amperes of test current (one-sixth of full-load HVDC during emergency conditions) effects of the test current can be observed on pipelines for a distance of 160 miles from the northerly HVDC ground electrode and 113 miles from the southerly HVDC electrode. Beyond these radial distances from the ground electrodes, no effects of test current were observed. Other variables measured were structure-to-soil potentials, current changes, voltage changes, and corrosion potential. Almost all of the pipeline studied in this report were cathodically protected.
PR-179-13201-R01 Cylinder Wall Lubrication for Power Cylinder Timed Lube Oil Injection
Authors: Olsen  , Luedeman  , Lanham
Published: August 2023

A retrofit lube oil injection system is designed with the capability of injecting oil through two lube ports on each cylinder at any time during the engine cycle. The system is installed and tested on a Cooper-Bessemer GMV4 engine. Variations in number of skip cycles, average lube rate, and injection timing are evaluated. Lube oil carry-over is quantified using a dilution tunnel and a standard particulate matter gravimetric measurement technique. Cylinder wall lubrication is quantified using a custom designed fixture that is inserted into the fuel valve port between data points when the engine is shut down. The best lube oil carry-over results for nominal lube rate are obtained by injecting every fourth cycle and injection timing roughly corresponding to the time the piston rings pass the lube ports during expansion.
PR-179-13205-R01 Field Evaluation of Oxidation Catalyst Degradation - 2-Stroke Lean-Burn NG Engine
Authors: Baumgardner  , Davis  , Olsen
Published: August 2023

This study examines the degradation of an exhaust oxidation catalyst on a Cooper-Bessemer GMVH 12C2 gas engine. Critical parameters were determined, such as light-off temperature and reduction efficiency at 450 and 600?F. The catalyst surface was analyzed to examine the location and rate of poison deposition. Catalyst life was examined based on NESHAP guidelines. Catalyst life is strongly dependent on catalyst temperature and space velocity. For similar industrial applications, if the engine unit particulars are known, site operators can use the information in this study to predict when the oxidation catalyst will need to be either replaced or regenerated (washed).
PR-471-14207-R01 Development of Field Pump Performance Testing Procedure
Authors: Robinett Fred
Published: August 2023

Performance testing pumps in the field can be challenging and even more complicated when the pump is in crude oil pipeline service. Pumps installed in crude oil pipelines normally do not meet the basic requirements set forth in typical pump testing standards, additionally crude oil fluid properties are irregular, thus making it difficult to obtain the desired accuracy for proper evaluation and comparison to factory tests. All inconsistencies need to be evaluated and reconciled to successfully field performance test pumps pumping viscous fluid. The objective of this project is to develop a practical field test procedure that can be applied to large high volume centrifugal pumps in pipelines transporting viscous fluids, specifically crude oil. There are many variables affecting field performance testing of crude oil pipeline pumps making it nearly impossible to fully analyze all possible combination of test measurements. The field pump performance test procedure provides practical guidance to assess the potential uncertainty of the measurements and making sensible corrections. Using the field testing procedure actual pump viscous performances can be measured and the results used to validate performances measured during factory tests on water and corrected for viscosity per the Hydraulic Institute (HI) 9.6.7, "Effects of Liquid Viscosity on Rotordynamic Pump Performance". The long term goal is to utilize the measured viscous performances using the field pump performance testing procedure to either validate or improve the current correlations between pump water performance and viscous performance set forth by HI, which are principally based on smaller pump tests. By assuring the viscous corrections are correct the pump and drive system sizing may be optimized.
L20010 Transient Flow of Gas
Authors: Hannah K. W. , Batey E. H. , Wilkinson J. F. , Holiday D. H.
Published: August 2023

Developments are necessary to apply automation concepts to the gas industry, in this case, a mathematical model for a pipeline system.

This report has two purposes. First, it is a survey of the research conducted in the PRCI NX-37 Transient Flow Study in 1962. Then enough details are presented on the two major computational techniques developed (the special numerical integration and the transfer function) to enable those interested persons within the gas industry to duplicate the techniques.
L19724 A Study to Evaluate the Stability of Underground Gas Storage Reservoirs
Authors: Hardy
Published: August 2023

One of the most pressing problems of the Natural Gas Industry today is that of locating and developing sufficient underground storage reservoir capacity to meet peak seasonal demands. In these reservoirs, the gas is stored under pressure in the pore spaces with in the rock that originally contained gas, oil or water. Since it is economically desirable to store the gas at the maximum possible pressure, an accurate value for the optimum pressure, namely the maximum pressure to which the reservoir could be pressurized and still remain mechanically stable, is of great importance.

This report presents the results of a five-year study established to investigate the stability of underground gas storage reservoirs. The main object of this study was the evaluation of a suitable criterion for optimum pressurization based on the principles of rock mechanics. Basically the research program was oriented along two parallel lines of approach consisting of laboratory studies of reservoir models and associated analytical studies. Both approaches have innate defects due to necessary simplifications; however, by carrying out both studies simultaneously and comparing the results, it was possible to draw a number of meaningful conclusions from the overall study.
L51451 Shot Peening and Grit Blasting on the Stress-Corrosion Cracking Behavior of Line-Pipe Steel
Authors: Koch
Published: August 2023

Laboratory experiments and field studies conducted in the Stress-Corrosion-Cracking Phase of the NG-18 program have demonstrated that there are a number of factors that influence the initiation and growth rate of stress-corrosion cracks in pipeline steels. Chief among these are: (1) the susceptibility of the steel, (2) the stress level and the strain rate, (3) the chemical environment in contact with the steel surface, (4) the electrochemical potential established on the steel surface, and (5) the temperature of the steel/environment system. These five factors are strongly interrelated in rather complex ways. However, it has been recognized that, for stress-corrosion cracks to initiate or grow, each of the five factors must be present concurrently and at appropriate values.As a result of these requirements, modification of any one of the factors is often sufficient to prevent or appreciably retard stress-corrosion cracking.

Result: The objectives of this study were to demonstrate the beneficial effect of shot peening and grit blasting; determine the minimum amount of grit blasting needed to increase the stress-corrosion threshold stress to at least80 percent of the specified minimum yield stress (SMYS); and determine practical parameters to control the degree of grit blasting and to determine the effect of oxidation (rusting) after blasting on potential stability in the stress-corrosion cracking range.

Laboratory experiments were carried out to investigate the effect of shot peening and grit blasting on the resistance to stress-corrosion cracking of pipe steels. It was demonstrated that both shot peening and grit blasting could increase the resistance to stress-corrosion cracking. However, since grit blasting is a more commonly used method of treating pipe-steel surface than shot peening, the emphasis in this report was placed on grit blasting.
L51510 Field Observations of Two-Phase Flow in the Matagorda Offshore Pipeline System
Authors: Allison
Published: August 2023

Offshore gas production typically involves the simultaneous flow of oil and/or condensate. The oil may he entrained in the gas rising in the vertical well from the sea-bed or may flow under its own pressure gradient; condensate may result from the reduction of pressure from well conditions to pipeline transport pressure and from cooling sea temperatures. It would be unduly expensive to build a gas-liquid separation facility on a production platform, followed by two separate pipeline transport systems for the two phases. It is therefore desirable to examine pipeline systems that carry hydrocarbon liquid and gas together.

Two-phase flow of oil and gas under steady-state operation of the Matagorda Offshore Pipeline System was observed by nuclear densitometry at two onshore sites. Oil flowed into the pipeline system at an average rate of 1.6 Bbl/ MMSCF over the two-month data acquisition period; gas flow was constant at about 200 MMSCF per day.
L51570 Energy Based Pipe-Soil Interaction Models
Authors: Lieng  , Sotberg  , Brennodden
Published: August 2023

The purpose of this project was to complete a handbook with practical design procedures for submarine pipeline on-bottom stability. The remaining part of the handbook was primarily a description of the interaction between non-trenched pipelines and the seabed where the pipelines were free to move under environmental loading.

The objective of this project was to determine the lateral soil resistance forces on a pipeline moving cyclically during hydro-dynamic loading. To meet the goal, full-scale pipe-soil interaction tests were conducted. The models presented in this report are based on the results and general understanding obtained from 110 experimental tests of pipe-soil interaction on loose and dense sand, and soft clay. Raw data from 29 experimental tests on stiff clay in the PIPESTAB project have been qualitatively considered.
L51656 Shielding Effects on Concrete and Foam External Pipeline Coatings
Authors: Brongers  , Beavers
Published: August 2023

Protection of gas-transmission pipelines from external corrosion is achieved by the application of a good anticorrosion coating and cathodic protection. In very rocky areas, pipeline-construction operations sometimes dictate that an external impact-resistant or barrier material be applied over the pipe to protect the anticorrosion coating from damage during backfilling. The use of a select backfill, such as compacted sand, is often specified, but transportation of the backfill and access to sufficient right-of-way to truck the sand into more remote areas becomes costly. As an alternative, recent practice has been to specify that a barrier coating of concrete or urethane foam be applied over the anticorrosion coating. However, concern has been raised regarding possible shielding of cathodic-protection currents by these external barrier materials.

This project investigates the shielding effects of barrier coatings on attempts to maintain CP levels on natural gas pipelines. Investigation included lab experiments with five representative barrier coatings materials carried out to determine the degree to which shielding occurred and the levels of CP needed to overcome this effect when occurring.
L51709 Development-Test Electronic Gas Admission for Large Bore Engines
Authors: Willson
Published: August 2023

The pipeline industry uses over 8,000 large bore engines in gas transmission/compression service". These engines are typically gas fueled and spark ignited. Some early versions of the engines are piston scavenged, but most are turbocharged. Some models, especially those equipped for lean burn operation, utilize pre-combustion chambers for enhanced ignition. Typically, the gaseous fuel is admitted directly into the top of the engine combustion chamber by a cam-operated, mechanical gas admission valve (MGAV). The MGAV is operated by an engine driven cam, cam follower, push rod, and rocker assembly. Such mechanisms offer little in the way of adjustability of the gas admission event: the ability to change the start of gas admission (SOA) and end of gas admission (EOA). The gas admission system is generally optimized for a particular mode of engine operation, typically rated speed and full load, and is fixed in that state. Desired changes in the gas admission cycle are not easily accomplished. At the same time, however, undesired changes commonly occur due to wear, failure, and mis-adjustment of the MGAV drive train.

This report documents the development of a natural gas-fueled large-bore engine test bed (LBET) at Colorado State University and the subsequent test of an electronic gas admissions valve (EGAV) with in-cylinder pressure feedback. The LBET is now a state-of-the-art natural gas-fueled test facility. It will be open for use in late 1994 or early 1995 to all parties interested in testing equipment that might lead to safer, more economical and cleaner burning gas fueled engines. The EGAV tests were successful. The valve allows for precise control of fuel admission and end of admission timing. This results in the engine running in a real-time balance condition. Laboratory tests showed a 30% reduction of hydrocarbons and nitrous oxides reductions with a 2% reduction in fuel consumption. Field testing will continue in 1995 prior to commercialization.
L51715 Field Testing the Criteria for Cathodic Protection of Buried Pipelines
Authors: Botros
Published: August 2023

There are three (3) documented Cathodic Protection (CP) criteria included in the NACE standards. The appropriate use of these are often debated and sometimes thought to be conservative in dry soils and possibly insufficient in some wet soil conditions. The need exists to evaluate the risks of an improperly installed and/or maintained CP system. The criteria for cathodic protection have been the subject of various research projects conducted for the Pipeline Research Council International, Inc. (PRCI) over a number of years. The programs have responded to the need to establish whether the present criteria are adequate or inadequate, and under what conditions, and whether the specific requirements for protection may depend upon the particular soil environment. The results of this study provide a comprehensive overview of the technical literature and the laboratory studies that formed the basis for this work. The results of this work include the first systematic study of the criteria as installed in the field. Field studies were initiated in 1984 with a multiyear (thru 1994) plan and objective of verifying the requirements for protection in a variety of natural environments, some of which were studied in the earlier laboratory research. Part I: Results of the research.Part II: Applications to the study, the limitations, methods of determining requirements of the pipeline, and the measurements needed to implement the results (60 figures and 56 tables).Part III: Study data (100 pages of charts and tables)
PR-443-13605-R01 Sensors for Gas Quality Monitoring
Authors: Deininger
Published: August 2023

The purpose of this project was to determine the suitability of low cost environmental air quality sensors, for detection of pipeline gas quality. In particular, this project examined options for detection and quantification of hydrogen sulfide (H2S), water (H2O), and oxygen (O2). All of the sensors used were based on Synkeras existing anodic aluminum oxide (AAO) platform and detection chemistry. The key challenge of this effort was laboratory based demonstration of the feasibility of detecting these three components in natural gas at pressures exceeding 1 atmosphere
L51565 Emissions Data for Stationary Engines in the Natural Gas Pipeline Transmission Industry
Authors: Dietzmann  , Urban
Published: August 2023

In 1972, PRCI Project PR-15-61 was initiated to measure exhaust emissions from stationary reciprocating gas engines and gas turbines used in natural gas compressor stations. Emission rates of oxides of nitrogen (NOx), hydrocarbons (HC), and carbon monoxide (CO) were measured from 59 reciprocating gas engines and nine gas turbines. During and subsequent to 1972, the PRCI laboratories and various PRCI member companies conducted emissions measurements. In 1978, PRCI Project PR-15-92 was initiated to conduct additional emissions measurements. That project involved 55 reciprocating gas engines and 11 gas turbines. All of those data were included in the May 1980 revision to the compilation of emissions data. Subsequent to the May 1980 revision, additional emissions measurements were conducted under PRCI Projects PR-15425 and PR-15-613, and emissions data were obtained from gas transmission companies and gas engine manufacturers in PR-15-613. These additional data are included in this 1988 reissue of the compilation.

The emissions data presented in this data book have been obtained from projects conducted or sponsored by the Pipeline Research Committee of the Pipeline Research Council International (PRCI), individual PRCI member companies, or gas engine manufacturers. Data included are from in-use reciprocating engines and gas turbines that have been in-service for anywhere from less than a year to one or more decades. These data are generally presented as received. Editing has been limited to omitting data for entire tests only where the data are obviously in error and to identifying specific erroneous or questionable items within a test.
L51703 High Pressure Pipe Design
Authors: Williams
Published: August 2023

Current practices in the pipeline industry require increased use of high pressure pipe and pipe fittings to meet expanding natural gas transportation requirements. A study of the current practices in the design and manufacture of pipe and pipe fittings (size on size tees, elbows, concentric reducers) in the range of 16 to 36 inch and with design pressures up to 3000 psi was needed. It was determined that yield strength is not significant to burst pressure or to fatigue, but tensile strength is significant to both. Ultimate tensile strength can be estimated on fittings of unknown origin by non-destructive hardness tests. Recommendations to users based on this study are included in this report. This study includes dimensional data from manufacturers and from fittings and pipe obtained from the Williams Transco unit stock. In addition this study includes comprehensive research of existing standards, linear and non-linear finite element analysis results and full-size instrumented fitting burst test data are included.
L51640 Improved Pipe-to-Soil Potential Survey Methods
Authors: Thompson  , Lawson
Published: August 2023

Pipe-to-soil potential measurements are the primary means for monitoring the effectiveness of cathodic protection (CP) systems. All criteria for cathodic protection employ, in one form or another, a potential measurement of the pipe with respect to a reference electrode. Although the pipeline industry obviously depends on pipe-to-soil potential measurements for monitoring CP systems, very little is known concerning what portion of the pipe is being sampled by the potential measurement. Prior to performing this project, many questions remained unanswered, such as: (1) what is the length of pipe being sampled by aboveground measurements, (2) is the potential sampled an average value around the circumference of the pipe or do above-ground measurements sample only the potential at the top of the pipe, and (3) how far away can a holiday or potential anomaly be detected.

The overall objective of this research program was to improve the ability to perform and interpret close interval on-potential and off-potential surveys. The following general conclusion can be made based on the results of this study. Ground level potential measurements provide average potential values, which are weighed based on pipe diameter, pipe depth, coating versus bare pipe, and other factors. Thus, close interval surveys should be considered as another tool to provide information on the condition of the pipe but should not be interpreted as providing definitive information on that condition.

Benefit: This research was a three-year program conducted for the Corrosion Supervisory Committee of PRCI with the main focus directed at establishing the area of pipe sampled during a pipe-to-soil potential measurement. The program was divided into two parts: bare pipelines and coated pipelines. The work examining bare pipelines was performed during 1988 and 1989, and the work examining coated pipelines was performed during 1990. The overall objective of this program was to improve the ability to perform and interpret close-interval potential surveys.
L51764 Hydrogen Cracking in the Heat-Affected Zone of High-Strength Steels-Year 2
Authors: Graville
Published: August 2023

During year 1 of this project a test to evaluate the sensitivity of the heat affected zone (HAZ) to hydrogen cracking was developed. This was in response to a need for a test which provided unambiguous results in contrast to existing test methods which often led to difficulties in interpretation. For example, WIC tests usually cracked in the weld metal rather than the HAZ and therefore did not produce a clear indication of the sensistivity of the HAZ. The new test involves a machined notch which can be placed in the HAZ thus forcing crack initiation to occur in the desired region. A further advantage of the new test is that it is quantitative with each test specimen providing a measure of the sensitivity of the HAZ in that test. Existing tests are usually of the crack/no-crack type requiring a series of tests at different preheats to be carried out in order to establish a critical value. This is an expensive, time-consuming approach. The new test measures the deflection to first load drop (normally the onset of significant cracking) when the welded specimen is loaded in bending. It was also shown during the first year of the project that the simple geometry of the test lends itself to easy analysis enabling the stress/strain distribution to be calculated by finite element analysis. The quantitative measurement of susceptibility in the test enabled the cracking of more complex welds to be predicted on the basis of a local critical hydrogen model.

The objective of the work was to extend the notched bend test to the evaluation of weld metal sensitivity to hydrogen cracking. The experiments were designed to determine whether the test could discriminate between two different weld metals and to study the effects of reducing hydrogen content. In addition, finite element analysis of the weld metal test was carried out and finite difference analysis used to predict the local hydrogen concentration. This work modifies the notched bend test, developed for evaluating the sensitivity of the heat affected zone (HAZ), to allow the evaluation of weld metal. The results showed that weld metal could readily be evaluated, with the test discriminating among weld metals of different composition and hydrogen contact. Finite element analysis was undertaken and showed that for the two weld metals tested, cracking occurred at the same local stress when the hydrogen content was the same, despite differences in strength. A finite model was used to calculate the distribution of hydrogen as a function of aging time. Although the general trends were confirmed by the experimental measurements of hydrogen content, there was considerable scatter attributed to the small hydrogen volumes measured.
L51784 CO2-HS Corrosion Under Wet Low-Flow Gas in Presence of Bicarbonate Chloride and Oxygen
Authors: Lyle
Published: August 2023

The ability to transport wet, untreated natural gases through pipelines offshore or at other inaccessible locations is an important factor in the development of new gas fields. When a wet gas contains CO2 and H2 S, the internal corrosion rate of steel pipelines may be expected to increase. Considerable work has been done to define effects of CO2 and H2 S on corrosion rates of pipeline, casing, and tubing steels, particularly at higher pressures and temperatures typical of downhole environments and in gases in which CO2 is the only acid gas present. In particular, studies by de Waard and Milliams resulted in development of an equation for predicting corrosion rates of steels exposed to water saturated with natural gases containing CO2 . However, the de Waard-Milliams equation cannot be used for gases containing H2 S, since it is applicable when CO2 is the only acid gas present.

This report was specifically initiated to provide estimates of internal corrosion rates in inaccessible (offshore) pipeline locations from analyses of gas and water samples taken in accessible (onshore) locations. It addresses the ability to transport wet, untreated natural gases through pipelines offshore or at other inaccessible locations, and the internal corrosion rates of steel pipelines.
L51792 External Corrosion Control Monitoring Practices - Volumes I and II
Authors: Thompson  , Lawson
Published: August 2023

The primary means of corrosion control for buried pipelines is the use of an external pipeline coating and the application of cathodic protection (CP). Monitoring the effectiveness of the corro sion control system is critical to the safe operation of natural gas pipelines. NACE International has established criteria andrecommended practices for monitoring the effectiveness of CP systems (RPO169-96). These practices and criteria have generally been accepted by regulatory agencies. Over the years a significant amount of research has been performed that is related to monitoring practices. Much of this research has been directed at improving measurement techniques that are aimed at satisfying the NACE criteria. In general, no significant effort has been made to incorporate research into currently used monitoring practices.

The overall objectives of this project were (1) to consolidate research previously performed on monitoring the effectiveness of cathodic protection of pipelines, (2) to analyze the different monitoring techniques in light of the research, and (3) to produce monitoring guidelines that describe the application of these monitoring techniques for typical natural gas pipelines. The scope of this project was limited to the review of previous work, both PRCI funded and the open literature, and discussions with industry personnel. No field work or laboratory experiments were conducted. This project was further limited to the review of methodologies related to monitoring the effectiveness of the CP system and does not include methods for evaluating coatings. The research project was divided into the following two tasks: Task 1 - Review of Research and Practices and Task 2 - Development of Guidelines. This work was a consolidation of research that has been performed by the PRCI and others over the past several years. This review took the individual monitoring techniques (on-potential, off-potential, depolarized potential, close interval survey, etc.) and applied them to the typical pipeline scenarios (poorly-coated line, well-coated line, foreign line crossing, area with dynamic stray current, etc.). Each individual monitoring technique is summarized in terms of purpose, description, application, limitations, special considerations, and equipment requirements. Each pipeline scenario is supported with composite and line maps and the guidelines for each scenario are described in terms of a general description, applicable techniques, special considerations, measurement procedures, measurement locations, measurement frequency, applicable criteria, and data interpretation.