bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shell-side Coefficients of Heat Transfer in a Baffled Heat Exchanger
Authors: Gardner H. S. , Siller Irving 
Published: December 2022

Abstract
The shell-side film coefficient of heat transfer in a half-moon baffled shell-and-tube laboratory heat exchanger was studied under heating and cooling conditions. Data were taken at 1 and 2-in. baffle spacings with water and three different oils. It was found that Short’s method of correlation (1), a plot of (hsDok) (kCpμ)0.32 (PP−Do)0.5 versus (DoGxμ) adequately represented all variables, but gave different lines for heating and cooling runs. For the oil data, the introduction of a viscosity ratio (μμw)0.19 gave a general correlation resulting in the equation (hsDok) =1.10 (Cpμk)0.32 (P−DoP)0.5(μμw)0.19(DoGxμ)0.56
Fatigue Tests of Welding Elbows and Comparable Double-Mitre Bends
Authors: Markl A. R. C. 
Published: December 2022

Abstract
It has long been known that the increased flexibility of curved pipe, resulting from its ovalization under the influence of bending moments, is reflected in increased stresses which are customarily evaluated by applying intensification factors to the stresses evaluated by the common beam theory. No similar information has heretofore been published regarding mitre joints. On the basis of comparative full-scale fatigue tests, the present investigation shows that, for double-mitre bends of given proportions, the stress intensifications (at the corners) are 20 per cent greater than for long-radius welding elbows when bending moments are applied tending to open or close the bend; and 70 per cent greater when bending is done sidewise, out of the plane of curvature. Expressed in terms of fatigue life under identical conditions of pipe-line expansion, this means that welding elbows will withstand 2½ times as many stress reversals in bending in the plane, and 14 times as many cycles in bending transverse to the plane of curvature, as compared with mitre bends. Indications were obtained also that internal pressure has no marked effect on the magnitude of the stress intensifications encountered. Stress-relieving and grinding the welds likewise produces no significant change in the endurance strength.
Ignition and Flame Stabilization in Gases
Authors: Lewis Bernard , von Elbe Guenther 
Published: December 2022

Abstract
The self-ignition of a volume of explosive gas mixture is understood to be the transition from slow to very rapid chemical reaction with approximately adiabatic heat evolution. Two known processes bring this about. They are distinguished as thermal and branched-chain explosion. In the former, the chemical reaction becomes self-accelerating owing to the temperature rise. In the latter, the self-acceleration is caused by the formation of chemically active particles at a rate that exceeds the rate of destruction of these particles. A peculiar process of the latter type plays an important contributory part in engine knock. Local ignition, as by a spark, results in the formation of a combustion wave which propagates through the explosive mixture in a manner analogous to Huyghen’s principle for the propagation of a light wave. Small sparks do not produce ignition. The minimum ignition repuirement of electric capacitance sparks in mixtures of methane or other hydrocarbons with oxygen and nitrogen is found to be only the spark energy. This is theoretically explained, and the minimum spark-ignition energy is shown to be a function of the burning velocity, the width of the combustion wave, and other variables of the gas mixture in agreement with experimental data. A combustion wave in a stream of explosive gas mixture becomes stationary, i.e., the flame becomes stable, when the burning velocity is equal to the gas velocity somewhere in the wave and is nowhere larger than the gas velocity. The mechanism is described by which the condition of equality of burning velocity and gas velocity is realized at the rim of a burner tube. It is shown that the limits for flash back and blowoff correspond to critical values of the gas-velocity gradient at the stream boundary. This applies equally to the outer boundary and any inner boundary formed by solid objects in the stream.
Development of Cleavage Fractures in Mild Steels
Authors: Bagsar A. B. 
Published: December 2022

Abstract
The susceptibility of several types and thicknesses of mild steel of ship-plate and pressure-vessel qualities and of samples of welds to development of cleavage or brittle fractures has been determined by a new test, termed the “cleavage-tear” test, in which a notched tensile-bend type of test coupon is used. The effects of notch and coupon geometries, load eccentricity, rate of loading, testing temperature, and of heat-treatments were investigated.
At temperatures below the transition-temperature range, the presence of a notch of proper geometry and orientation was found to create a state of multiaxial stress which appears to expand the elastic range of steel and to raise its proportional limit almost to coincide with its breaking point. The breaking strength of rectangular sections containing a notch of the foregoing type was found to decrease, and susceptibility to cleavage fracturing to increase as the notch root radius was decreased. Within the limits investigated, the breaking strength of steel was found to be modified by the notch geometry, this modification being practically independent of the size effect if the section was 6 in. or greater in depth. The transition temperatures for the steels investigated in the as-rolled condition were found to be about 100 deg F higher than those indicated by the conventional Charpy impact test, and are considered to be more nearly indicative of behavior of steels in service. Nevertheless, the transition temperature of a steel cannot be defined for service conditions unless the state of stress which prevails under the same conditions is also defined.
Two types of fracture were encountered, one being the brittle or cleavage type exhibiting no appreciable deformation and lower nominal breaking strength, and the second the shear type exhibiting normal ductility and higher breaking strength. Fractures above the transition range were of the shear type and below that temperature range of the cleavage type. On the basis of the test data presented, reconsideration of our present factors of safety is suggested for monolithic structures with the object of safeguarding against the possibility of development of large cleavage fractures from small discontinuities, notches, or cracks. Other remedial measures for minimizing the damage of cleavage fractures, including modifications in design and material of construction, are suggested.
A Study of the Properties of 0.5 Per Cent Chromium—0.5 Per Cent Molybdenum Pipe Steel
Authors: Fitzgerald R. C. , Wilder A. B. , Smith G. V. , White A. E. 
Published: December 2022

Abstract
Study of the mechanical properties, including creep, and of the welding and fabrication characteristics of steel containing 0.5 per cent chromium and 0.5 per cent molybdenum, designed for elevated-temperature service, has shown this grade to be essentially similar to 0.5 per cent molybdenum steel without chromium. However, elevated-temperature exposure tests have shown the steel whether deoxidized with aluminum or not, to be resistant to graphitization in butt-welded pipe as well as bead-weld tests lasting up to 15,000 hr at 1025 F and 12,000 hr at 1100 F. Scaling tests and hardness and notch-impact tests before and after air exposure at elevated temperature have indicated that only slight oxidation and little or no embrittlement may be anticipated during service of this grade of steel.
Comparison of Radiation-Conduction Transfer Involving Complex Solid Shapes Determined by Topological Optimization and a Heuristic Technique
Authors: Sevart Chadwick D. , Bergman Theodore L. 
Published: December 2022

Abstract
A solid growth method (SGM) and a dual solid method (DSM), both recently developed, are each used to predict solid shapes that provide minimal total (conduction + radiation) resistance to heat transfer in a system involving conduction in a solid whose shape is to be determined, conduction in an adjoining gas, and radiation transfer between opaque, diffuse, and gray surfaces. The performance of each method is illustrated by examining solid configurations and temperature distributions that evolve as the mass of solid is gradually increased (SGM) or reconfigured (DSM). With use of either the SGM or the DSM, the solid evolves in a manner that enhances radiation heat transfer, and it is shown that neglecting radiation in the determination of solid configurations that optimize heat transfer performance is, in general, not justified. Despite the formalism of the DSM, which is based on topological optimization, the thermal performance of the DSM only marginally surpasses that of the SGM in terms of calculated total thermal resistance values, and only for cases involving a high solid thermal conductivity. For low solid thermal conductivity cases, the SGM outperforms the DSM with the difference in performance attributed to the inability of DSM to capture the fine solid structure of the SGM predictions.
Verification and Validation of Computational Fluid Dynamic Simulations of a FOWT Semi-Submersible Under Bichromatic and Random Waves
Authors: Wang Yu , Chen Hamn-Ching 
Published: December 2022

AbstractIn the present work, an extensive verification and validation study is performed to evaluate the accuracy and credibility for computational fluid dynamic (CFD) simulations of the hydrodynamic responses of a semi-submersible floating offshore wind turbine (FOWT) platform under bichromatic waves and random waves. A dynamic mooring model is coupled with the CFD code to accurately simulate the mooring system. For the bichromatic wave cases, the surge, heave, and pitch response amplitude operators (RAOs) at wave frequencies, mean surge offset and mean surge force of the semi-submersible platform are investigated. The numerical uncertainties of the above metrics are quantified, which are primarily sourced from the discretization uncertainty. For the random wave cases, the surge, heave, and pitch power spectral density (PSD) sums in wave frequency range and low frequency range are validated against the experimental results. The numerical uncertainty derived from the bichromatic wave cases is applied in the validation of the random wave cases. The PSD sums in wave frequency range have achieved the validation within the validation uncertainty. Though the PSD sums in low-frequency range are under-predicted, the results with the utilization of the CFD code agree more with the experimental value than the results from mid-fidelity tools.
Adapted Physical Educators Navigating Relationships With School Administrators
Authors: Richards Kevin Andrew , McNamara Scott , Trad Alyssa M. , Hill Lauren , Abdallah Sarena 
Published: December 2022

School administrators represent key agents of socialization for teachers within their schools, including adapted physical educators who design and implement instruction for youth with disabilities, often across multiple school sites. The purpose of this study was to understand how adapted physical educators navigate and build relationships with administrators in the schools where they teach. Data were collected through semistructured interviews with 24 adapted physical educators from the U.S. state of California and analyzed using a multiphase approach. Analysis suggested both the importance of and challenges with building effective relationships with administrators. Themes included the following: (a) Administrators do not understand adapted physical education, which impacts programs and students; (b) the importance of relationship building in cultivating principal support; and (c) relationship development requires intentionality, but results in trust and motivation. Results are discussed using role socialization theory, and recommendations for the preparation of both adapted physical educators and school principals are discussed.
A major Miocene deepwater mud canopy system: The North Sabah–Pagasa Wedge, northwestern Borneo
Authors: Morley C.K. , Promrak W. , Apuanram W. , Chaiyo P. , Chantraprasert S. , Ong D. , Suphawajruksakul A. , Thaemsiri N. , Tingay M. 
Published: December 2022

Abstract
Three-dimensional seismic reflection data, well data, and analogues from areas with extensive shale tectonics indicate that the enigmatic deepwater “shale nappe or thrust sheet” region of northern offshore Sabah, Malaysia, now referred to as the North Sabah–Pagasa Wedge (NSPW), is actually a region of major mobile shale activity characterized by mini-basins and mud pipes, chambers, and volcanoes. A short burst of extensive mud volcano activity produced a submarine mud canopy complex composed of ~50 mud volcano centers (each probably composed of multiple mud volcanoes) that cover individual areas of between 4 and 80 km2. The total area of dense mud canopy development is ~1900 km2. During the middle Miocene, the post-collisional NSPW was composed predominantly of overpressured shales that were loaded by as much as 4 km thickness of clastics in a series of mini-basins. Following mini-basin development, there was a very important phase of mud volcanism, which built extensive mud canopies (coalesced mud flows) and vent complexes. The mud canopies affected deposition of the overlying and interfingering deposits, including late middle to early late Miocene deepwater turbidite sandstones, which are reservoirs in some fields (e.g., Rotan field). The presence of the extensive mud volcanoes indicates very large volumes of gas had to be generated within the NSPW to drive the mud volcanism. The Sabah example is only the second mud canopy system to be described in the literature and is the largest and most complex.
Tectonic setting of metamorphism and exhumation of eclogite-facies rocks in the South Beishan orogen, northwestern China
Authors: Li Jie , Wu Chen , Chen Xuanhua , Yin An , Zuza Andrew V. , Haproff Peter J. , Chen Yanfei , Wang Luojuan , Shao Zhaogang 
Published: December 2022

AbstractHigh-pressure metamorphic rocks occur as distinct belts along subduction zones and collisional orogens or as isolated blocks within orogens or mélanges and represent continental materials that were subducted to deep depths and subsequently exhumed to the shallow crust. Understanding the burial and exhumation processes and the sizes and shapes of the high-pressure blocks is important for providing insight into global geodynamics and plate tectonic processes. The South Beishan orogen of northwestern China is notable for the exposure of early Paleozoic high-pressure (HP), eclogite-facies metamorphic rocks, yet the tectonism associated with the HP metamorphism and mechanism of exhumation are poorly understood despite being key to understanding the tectonic evolution of the larger Central Asian Orogenic System. To address this issue, we examined the geometries, kinematics, and overprinting relationships of structures and determined the temperatures and timings of deformation and metamorphism of the HP rocks of the South Beishan orogen. Geochronological results show that the South Beishan orogen contains ca. 1.55–1.35 Ga basement metamorphic rocks and ca. 970–866 Ma granitoids generated during a regional tectono-magmatic event. Ca. 500–450 Ma crustal thickening and HP metamorphism may have been related to regional contraction in the South Beishan orogen. Ca. 900–800 Ma protoliths experienced eclogite-facies metamorphism (~1.2–2.1 GPa and ~700–800 °C) in thickened lower crust. These HP rocks were subsequently exhumed after ca. 450 Ma to mid-crustal depths in the footwall of a regional detachment fault during southeast-northwest–oriented crustal extension, possibly as the result of rollback of a subducted oceanic slab. Prior to ca. 438 Ma, north-south–oriented contraction resulted in isoclinal folding of the detachment fault and HP rocks. Following this contractional phase in the middle Mesozoic, the South Beishan orogen experienced thrusting interpreted to be the response to the closure of the Tethyan and Paleo-Asian Ocean domains. This contractional phase was followed by late Mesozoic extension and subsequent surface erosion that controlled exhumation of the HP rocks.
Flexible treatment of gestational diabetes mellitus adjusted according to intrauterine fetal growth versus treatment according to strict maternal glycemic parameters: a randomized clinical trial
Authors: Fernández-López Manuela , Blanco-Carnero José Eliseo , Guardia-Baena Juan Manuel , de Paco-Matallana Catalina , Aragón-Alonso Aurora , Hernández-Martínez Antonio Miguel 
Published: December 2022

IntroductionTo compare the conventional treatment of gestational diabetes mellitus (GDM) with flexible treatment according to the measurement of fetal abdominal circumference (AC) in daily clinical practice.Research design and methodsTwo hundred and sixty pregnant women diagnosed with GDM before week 34 were randomly placed in two groups: a control group, treated according to maternal capillary glycemia, and an experimental group, treated according to ultrasound parameters of fetal growth. The glycemic targets in the control group were blood glucose levels when fasting and 1 hour postprandial (<95/140 mg/dL). In the experimental group, glycemic targets depended on the percentile (p) of fetal AC: if AC p <75th, then blood glucose targets when fasting and at 1 hour postprandial were <120/180 mg/dL; and if AC p ≥75th, then the glycemic targets were <80/120 mg/dL. The follow-up of both groups was scheduled according to the GDM protocol of our diabetes and gestation unit.ResultsThe study was completed by 246 pregnant women, 125 in the control group and 121 in the experimental group. In the experimental group, insulin treatment and neonatal hypoglycemia were significantly lower (p=0.018 and p 0.035, respectively). No differences were observed in large and small infants according to gestational age. However, macrosomic infants were less frequent in the experimental group, although this difference did not reach statistical significance. In terms of gestation complications, the type of delivery and its complications and the rest of the neonatal complications analyzed, no significant differences were observed.ConclusionsThe treatment of flexible GDM according to the measurement of fetal AC is safe for the mother and the fetus and almost halves the number of pregnant women who require insulin treatment, without increasing the number of ultrasound checks or medical visits.
Doctors’ experiences of providing care in rural hospitals in Southern New Zealand: a qualitative study
Authors: Hedman Mante , Doolan-Noble Fiona , Stokes Tim , Brännström Margareta 
Published: December 2022

ObjectiveTo explore rural hospital doctors’ experiences of providing care in New Zealand rural hospitals.DesignThe study had a qualitative design, using qualitative content analysis.SettingThe study was conducted in South Island, New Zealand, and included nine different rural hospitals.RespondentsSemistructured interviews were conducted with 16 rural hospital doctors.ResultsThree themes were identified: ‘Applying a holistic perspective in the care’, ‘striving to maintain patient safety in sparsely populated areas’ and ‘cooperating in different teams around the patient’. Rural hospital care more than general hospital care was seen as offering a holistic perspective on patient care based on closeness to their home and family, the generalist perspective of care and personal continuity. The presentation of acute life-threatening low-frequency conditions at rural hospitals were associated with feelings of concern due to limited access to ambulance transportation and lack of experience.Overall, however, patient safety in rural hospitals was considered equal or better than in general hospitals. Doctors emphasised the central role of rural hospitals in the healthcare pathways of rural patients, and the advantages and disadvantages with small non-hierarchical multidisciplinary teams caring for patients. Collaboration with hospital specialists was generally perceived as good, although there was a sense that urban colleagues do not understand the additional medical and practical assessments needed in rural compared with the urban context.ConclusionsThis study provides an understanding of how rural hospital doctors value the holistic generalist perspective of rural hospital care, and of how they perceive the quality and safety of that care. The long distances to general hospital care for acute cases were considered concerning.
Prospective observational study of the challenges in diagnosing common neonatal conditions in Nigeria and Kenya
Authors: Staunton Aimee P , Nabwera Helen M , Allen Stephen J , Tongo Olukemi O , Akindolire Abimbola E , Abdulkadir Isa , Ezeaka Chinyere V , Ezenwa Beatrice N , Fajolu Iretiola B , Imam Zainab O , Umoru Dominic D , Otieno Walter , Nalwa Grace M , Olwala Macrine , Talbert Alison W , Andang'o Pauline E A , Mwangome Martha K , Abubakar Ismaela , Embleton Nicholas D 
Published: December 2022

ObjectivesAccurate and timely diagnosis of common neonatal conditions is crucial for reducing neonatal deaths. In low/middle-income countries with limited resources, there is sparse information on how neonatal diagnoses are made. The aim of this study was to describe the diagnostic criteria used for common conditions in neonatal units (NNUs) in Nigeria and Kenya.DesignProspective observational study. Standard case report forms for suspected sepsis, respiratory disorders, birth asphyxia and abdominal conditions were co-developed by the Neonatal Nutrition Network (https://www.lstmed.ac.uk/nnu) collaborators. Clinicians completed forms for all admissions to their NNUs. Key data were displayed using heatmaps.SettingFive NNUs in Nigeria and two in Kenya comprising the Neonatal Nutrition Network.Participants2851 neonates, which included all neonates admitted to the seven NNUs over a 6-month period.Results1230 (43.1%) neonates had suspected sepsis, 874 (30.6%) respiratory conditions, 587 (20.6%) birth asphyxia and 71 (2.5%) abdominal conditions. For all conditions and across all NNUs, clinical criteria were used consistently with sparse use of laboratory and radiological criteria.ConclusionOur findings highlight the reliance on clinical criteria and extremely limited use of diagnostic technologies for common conditions in NNUs in sub-Saharan Africa. This has implications for the management of neonatal conditions which often have overlapping clinical features. Strategies for implementation of diagnostic pathways and investment in affordable and sustainable diagnostics are needed to improve care for these vulnerable infants.