bluuebunny/crossref_metadata_2025 huggingface dataset:
Cultural Resources and Mobilization of Social Capital: The Case of Finding a Job
Authors: Cebula Michał
Published: July 2022

By combining the latest knowledge from cultural sociology and social network theories, a hypothesis is posed regarding the association between cultural consumption and social capital mobilization. On the classic example of looking for work, an assumption was made that persons who prefer or engage in a larger number of cultural forms (the so‐called omnivores) have greater chances to find work through social contacts than through any other methods or may count on social support when looking for job, and this relationship is stronger for non‐family than for family ties. These arguments are tested with the use of survey data collected in Poland in 2017 on a locally representative sample of adult residents aged 18–75. The results support the hypotheses and additionally show that people with different cultural profiles differ in their capacity to access and mobilize social resources. While participation in both highbrow and popular culture is efficacious, not all forms of the popular one are positively related to social resources. The article is closed with some concluding remarks, limitations of the study, and guidelines for future research.
Evaluation of the Studies at the University of the Third Age from the Perspectives of Its Members
Authors: Zanovitová Mária , Kalánková Dominika , Lepiešová Martina , Farský Ivan
Published: July 2022

The issue of education for the elderly is one of the current topics and is closely related to the process of active ageing. Its urgency is underlined by the increasing proportion of the elderly in the population. The importance of senior education lies in understanding the tasks of old age, facilitating adaptation to a changed lifestyle, and maintaining physical and mental activity within an orientation in a modern, rapidly changing world. Universities of the third age (U3A) are one of the options to ensure quality education for seniors. The presented study aimed to find out how the U3A members evaluate their study at U3A in terms of their satisfaction with the content, goals, methods, lecturers and course of the study; and to identify differences in the evaluation of the U3A study based on the study programme, age and gender. Through a self-designed questionnaire, the study involved 95 students, the U3A members at the Jessenius Faculty of Medicine, Comenius University in Martin (JFM CU), in the two study programmes, namely General Medicine and Senior Care. The bes t-evaluated area was the fulfilment of expectations during the study at U3A. Respondents consider the acquisition and deepening of new knowledge and new experience to be the most outstanding contribution of U3A education. Respondents significantly appreciated the readiness of lecturers and their pedagogical competence and skills. Respondents commented on the situational and institutional obstacles to studying at U3A; for most respondents, the obstacle was the accessibility of the educational institution and the distance to the public transport stop. Significant differences were found between the two study programmes in evaluating the length of lectures; the students of the General Medicine programme were more satisfied with the length of the lecture than the students of the Senior Care programme. Significant differences in terms of respondents‘ age were mainly related to accessibility and barriers in U3A education. In terms of gender, significant differences were noted in several areas; in contrast to men, women better rated the contribution of the UT3 study, the course and length of lectures, and studying at U3A met their expectations more than men. In the following period, based on the analysis and evaluation of the questionnaire, we would like to focus on strengthening the studies at U3A not only from the members’ perspective but also from the lecturers’. The results and findings presented can be a starting point for further research in the field of senior education at U3A.
The Fossil Fishes of the “Rocha” Collection Housed in the Museu Nacional and the Types Described by Jordan & Branner in 1908
Authors: Polck Márcia Reis , Silva Marcia Cristina , Ximenes Celso Lira , Carvalho Luciana Barbosa de , Monteiro Felipe Augusto Correia
Published: July 2022

In 1908, D.S. Jordan J.C. Branner described the following species of fossil fishes from the Araripe Basin: Calamopleurus vestitus, Cearana rochae, Enneles audax, and Tharrias araripis. Such material of the “Rocha Collection”, that was made by Francisco Dias da Rocha (1869-1960), were passed on to the Government of the State of Ceará. In 1961, Carlos de Paula Couto, negotiated the donation of the paleontological collections for the Museu Nacional. We review herein the history of the fossil fishes of the “Rocha Collection” that was housed in the Museu Nacional in, with an emphasis on type material. The documents and literature were consulted, and the fossil fishes were examined and photographed. This material corresponds to 12 catalogue numbers, three of which are replicas of the type- material housed in the Department of Geology, California Academy of Sciences, in California. The remaining nine numbers encompass 27 specimens referring to original material. The represented taxa are: Vinctifer comptoni, Notelops brama, Cladocyclus gardneri, Rhacolepis buccalis, Tharrhias araripis, and Brannerion sp. The only type material found was Cearana rochae, currently a synonym of Tharrhias araripis. This historical rescue of the “Rocha” collection type material will facilitate the investigation of researchers studying the paleoichthyofauna of the Araripe Basin.
Observations on Some Factors Affecting Timken Data for EP Lubricants
Authors: DeArdo A. J. , Kipp E. M.
Published: July 2022

The paper reports results of an investigation of variations in rubbing speed and viscosity variables when using the Timken machine for evaluation of EP lubricants.
On the Solution of the Reynolds Equation for Slider-Bearing Lubrication—VIII: The Optimum Slider Profile for Viscosity a Function of the Pressure
Authors: Charnes A. , Osterle F. , Saibel E.
Published: July 2022

Treating viscosity as a function of pressure, the problem of determining the optimum slider profile from the standpoint of load-supporting capacity is solved for the case of isothermal flow, and is discovered to yield the same profile as Rayleigh found assuming constant viscosity. It is shown how the increase in load-supporting capacity resulting from viscosity variation may be calculated.
Studies in Cold-Drawing: Part 1—Effect of Cold-Drawing on Steel
Authors: Majors H.
Published: July 2022

In the study of cold-drawing SAE 1020 steel rod various amounts up to a true reduction in area of 0.76, several properties were obtained such as hardness, torsion, and tension. Residual stresses were measured and the microstructure was examined. The effect of the amount of reduction and the direction of drawing per pass (defined as sequence in drawing) on the various properties was determined. Some exploratory work was conducted on the influence of prior cold work and fatigue-stressing on the brittle transition temperature. Effects of size, machining, and time after cold work upon the tension and torsion properties were observed. Cold-drawing is compared with cold-rolling. Part 2 consists of studies in cold-drawing 2S-O aluminum, while Part 3 discusses some measurements on the coefficient of friction.
Studies in Cold-Drawing: Part 2—Cold-Working 2S-O Aluminum
Authors: Majors H.
Published: July 2022

This is a study in the cold-working of 2S-O aluminum up to a true reduction in rod area of 0.76 by drawing through conical dies of 1 deg half-angle. Various properties were obtained such as true stress-strain diagrams in tension, hardness, conventional shear stress-strain diagrams, and the distribution of the residual stresses. The effect of the amount of reduction and the direction of drawing per pass (defined as sequence in drawing) on the properties were determined. Some fatigue data are reported. Drawing loads and ratios of yield strengths in torsion to tension are reported. Part 3 discusses some measurements on the coefficient of friction.
The Shear Stress in Metal Cutting
Authors: Shaw M. C. , Finnie Iain
Published: July 2022

When metal cutting stress-strain data are compared with data from other materials tests, poor agreement is observed. The several factors that could influence the flow stress in cutting are considered and it is found that the presence of a normal stress on the shear plane, the temperature on the shear plane, and the higher rates of strain in cutting are of negligible importance. The interrelationship between temperature and strain rate is treated theoretically and the two effects are found to tend to cancel. It is shown experimentally that a material cut does not behave as an ideal plastic, but that the modulus of strain hardening is essentially the same at the high rates of strain encountered in cutting as in other materials tests carried out at low rates of strain. The principal discrepancy between cutting and torsion test data is seen to be due to the smallness of specimen size in cutting. The size effect that is observed in materials tests (tension and torsion) is shown to be in good quantitative agreement with the size effect observed when metals are cut at different feed rates. The presence of flow ahead of the conventional shear plane near the free surface is demonstrated and the importance of this preflow discussed. Part of the discrepancy between cutting and torsion test data is found to be due to use of chip-length measurements in obtaining the shear area rather than measuring this value directly from photomicrographs. This flow ahead of the shear plane also is found to account for part of the discrepancy between computed and measured values of the shear angle.
Visualization Studies of Secondary Flows With Applications to Turbomachines
Authors: Herzig H. Z. , Hansen A. G.
Published: July 2022

The investigation reported in this paper is intended mainly as an exploratory inquiry into some fundamental aspects of the boundary-layer flows in turbomachines. These studies are preliminary to a more complete analysis of the flow in turbomachines. Nevertheless, the insight obtained into the secondary-flow patterns and behavior is fundamental in nature. Thus it may provide a basis for correlation and interpretation of other experimental data. When flow conditions are sufficiently similar to those which existed in these studies, the conclusions drawn from these tests may likewise serve to extend the understanding and correlation of other experimental data. It is further anticipated that the flow behavior observed experimentally in the various configurations may prove useful as a means for evaluating the reasonableness of various simplifying assumptions used in theoretical analyses. In particular, it might serve as a criterion both in the initial selection of the assumptions and in estimations of the physical validity of analytically obtained results.
The Influence of Surface Profile on the Load Capacity of Thrust Bearings With Centrally Pivoted Pads
Authors: Raimondi A. A. , Boyd John
Published: July 2022

This paper describes an analysis which reveals the significance of surface profile and its contribution to the load capacity of centrally pivoted pads. Experiments supporting the authors’ analysis are described. In addition, variable viscosity and variable density are evaluated and their effect on load capacity is noted.
Realizing Full Benefits of Centralized Control
Authors: Williamson J. D.
Published: July 2022

In his paper Mr. V. F. Estcourt points out that the principal reason for centralized control is to reduce manpower and thereby reduce operating costs.

Judging by the number of operators assigned per shift, many companies do not take full advantage of these savings, even allowing for variations in management policy in regard to equipment coverage.
Corrosion of Steel in Boilers—Attack by Dissolved Oxygen
Authors: Grabowski H. A.
Published: July 2022

The role of oxygen in the corrosion of internal surfaces of boiler-furnace-wall tubes has been discussed widely without arriving at consistent conclusions in respect to the maximum concentration of oxygen that can be tolerated and the exact cause of the initial pit formation at the tube surface. The present paper reviews the various theories that have been proposed to explain the severe, although local, corrosion of furnace-wall tubes in high-pressure boilers. Results of field tests of the oxygen record in utility-type boilers are presented. Metallurgical significance of failures and welding techniques also are discussed.
Pin-Fin Heat-Exchanger Surfaces
Authors: Kays W. M.
Published: July 2022

Plate-fin heat-transfer surfaces in which the fins are small-diameter circular pins, in contrast to fins in sheet form, are of interest in gas-flow heat-exchanger applications because of the extremely high heat-transfer conductances obtainable along with high fin effectiveness. This paper summarizes the previously available heat-transfer and flow-friction design data for such surfaces and presents new data recently obtained. A number of problems encountered in the development of these surfaces are discussed, including a serious pin-vibration problem, and a tendency for the flow to become completely laminar if the pins are in line and too closely spaced. All of the pin-fin surfaces considered have in-line pin arrangements, and it is concluded that a staggered pin arrangement will alleviate some of the undesirable features of the in-line arrangement. A heat-exchanger-design study is included to demonstrate that, despite the high friction factors characteristic of pin-fin surfaces, it is possible to design heat exchangers with these surfaces that are competitive, from a volume and weight point of view, with comparable plate-fin surfaces in which the fins are of continuous or louvered-sheet form.
Mechanism of Cavitation Inception and the Related Scale-Effects Problem
Authors: Kermeen R. W. , McGraw J. T. , Parkin B. R.
Published: July 2022

An experimental investigation of incipient cavitation is described and the relationship between these experiments and current theories is discussed. Experiments have indicated that the cavitation number for inception varies with free-stream velocity and body size for both streamlined and bluff bodies. Preliminary studies of the mechanism of cavitation were conducted in order to understand the reasons for the variations in cavitation performance. Photographic investigations have disclosed the effect of the boundary layer on cavitation inception for both streamlined and bluff bodies. In addition, this study has shown that tensions exist in the flow of ordinary water at incipient cavitation.
Fanning Friction Factors for Air Flow at Low Absolute Pressures in Cylindrical Pipes
Authors: Bohnet W. J. , Stinson L. S.
Published: July 2022

As there are no published data verifying the theoretical Fanning friction factors for streamline flow of air at low absolute pressures, an investigation was made of the pressure drops in 6 to 18-in-diam pipe lines in which room-temperature air was flowing at absolute pressures varying from 50 microns Hg to 1 mm Hg. The large number of pressure-drop readings taken at various rates of flow permits developing friction-factor curves for this type of flow. These are presented in this paper.
Interaction of Friction and Temperature at the Chip-Tool Interface in Metal Machining
Authors: Ling F. F. , Saibel Edward
Published: July 2022

The significance of chip-tool interface friction-temperature characteristics in metal machining is pointed out. For orthogonal metal machining with Type 2 chip an approximate analysis of the interface temperature, or cutting temperature, is given for linear friction-temperature characteristics and small rake angles. In the analysis, the coefficient of friction and the temperature are expressed in terms of the cutting velocity, the physical properties of the material, and constants obtained from the data of Chao and Trigger (1).
Thermodynamics of Supercritical-Pressure Steam-Power Plants
Authors: Bartels Jerome
Published: July 2022

This paper deals with the efficiencies that are thermodynamically obtainable from a steam-power cycle by utilizing throttle pressures exceeding the critical pressure of steam. The analysis starts with Rankine cycles, and then successively presents simple cycles, multiple reheat cycles, and increasingly more complex feed-heating arrangements. Thermal efficiencies and heat rates for these cycles are established, and explanations are offered to show why the results turn out the way they do.
Principles of Boiler Design for High Steam Temperatures
Authors: Kessler G. W.
Published: July 2022

For years, engineers have striven for better and more efficient boilers in their efforts to produce electric power at the lowest possible cost. Their success has been such that today the best possibilities for still greater economy lie in directions other than increased boiler efficiency. These possibilities include improvements in the heat cycle, in the methods of firing, in functional operation, and in the maintenance of boiler units. As the field for improvement narrows, the greatest attention is being focused on increased cycle efficiency as probably the most promising possibility for further reducing the cost of a kilowatthour.
Experimental Technique for Predicting the Dynamic Behavior of Rubber
Authors: Dove Richard , Murphy Glenn
Published: July 2022

An experimental technique is presented for evaluating those mechanical properties of materials which permit the prediction of the stress-strain diagram associated with a given strain-time diagram. Particular attention is given to the unrelaxed or dynamic modulus of elasticity and the relaxed modulus. It is shown how the energy loss for a cycle of loading and unloading depends on the rates of straining and unstraining as well as on any elapsed time between the straining and unstraining. The equipment and equations necessary to evaluate the properties and make the predictions are discussed. Several predicted stress-strain diagrams are compared with diagrams constructed from direct observations.
The Influence of Some Chemical and Physical Factors on the Formation of Deposits From Residual Fuels
Authors: Sulzer P. T.
Published: July 2022

The oil-ash-deposit problem in industrial gas-turbine plants is analyzed from both physical and chemical stand-points. Theory and experiments on the formation of ash during combustion enable important processes in the build-up of deposits to be understood. These are demonstrated by means of practical examples. Measurements of ash-deposit formation as a function of temperature, pressure, excess air, fuel-ash content, and test duration, are shown graphically and summarized in a formula.
Development of a Miniature Electrohydraulic Actuator
Authors: Lee S.-Y. , Shearer J. L.
Published: July 2022

A qualitative discussion is given of the factors establishing the need for a compact electrohydraulic actuator to operate at a relatively low input-power level and capable of providing an output motion proportional to the magnitude of an electric input signal. The basic requirements of such an actuator are discussed, and then the design of each of its components including torque motor, valve, ram, and feedback mechanism, are described in detail. The results of a dynamic analysis of the complete system are employed to show how adequate system damping is provided, and to show how theoretical speed of response is obtained. The results of steady-state and dynamic tests are compared with the results of the analytical work. This actuator has been found to fulfill the needs of a number of instrumentation and control applications, and preliminary tests using compressed air instead of hydraulic oil indicate that pneumatic operation of such a device is also feasible.
Dynamics in the Inlet System of a Four-Stroke Single-Cylinder Engine
Authors: Taylor C. F. , Livengood J. C. , Tsai D. H.
Published: July 2022

This paper presents the results of a recent investigation of the inlet process in a four-stroke, single-cylinder engine with an inlet pipe. The effects of inlet-pipe length, inlet-pipe diameter, inlet-valve timing, and some other design parameters were studied. The results showed that the dynamic effect of the inlet pipe on the engine volumetric efficiency was associated with (a) the process of accelerating the inlet-pipe air column during the first part of the inlet stroke, and taking advantage of the ramming of the air column during the last part of the same inlet stroke; and (b) the action of the standing wave set up in the air column during the preceding cycle. By a suitable choice of inlet pipe and valve timing, a considerable gain in volumetric efficiency over that for zero pipe could be obtained over a wide range of engine speed.
Studies in Lubrication—X: The Complete Journal Bearing With Circumferential Oil Inlet
Authors: Jacobson M. J. , Charnes A. , Saibel E.
Published: July 2022

An approximate pressure solution is developed for the Reynolds equation for the case of the end-lubricated complete journal bearing. This solution is used to obtain expressions for the load-carrying capacity, coefficient of friction, axial thrust, and rate of flow of lubricant. Finally, this solution is extended to the case of the circumferential oil inlet.
Modified Residual Fuel for Gas Turbines
Authors: Buckland B. O. , Sanders D. G.
Published: July 2022

Sodium in gas-turbine fuel causes rapid deposit formation as well as corrosion. Besides naturally contained sodium, sea-water contamination during transportation introduces additional amounts. In order to obtain the benefits of a low-sodium fuel, 90 per cent or more of the sodium is washed out of the fuel by a scheme described. The results of the desalting show that calcium also can be reduced substantially. Turbine tests of 50 to 1500 hr duration using these desalted fuels show that deposit can be almost eliminated by keeping both the sodium and the calcium below 10 parts per million. The steady-stage decrease in turbine efficiency resulting from burning these low-sodium, low-calcium fuels is shown to be about 2 per cent and the reduction in regenerator effectiveness about 5 points. A specification is proposed, defining a fuel which can be obtained at the point of use by means of the desalting method described and by adding a water solution of magnesium sulphate to the fuel just before it is burned. Treating vanadium-containing fuels with calcium or magnesium shows that, below 1650 F, magnesium is a better inhibitor than calcium and, since magnesium does not cause deposit, it is used. Lead in the fuel in sufficient quantities is shown to spoil, somewhat, the inhibition of vanadium by means of magnesium. There now appear to be at least two methods available for modifying residual fuel to make it suitable for long-life gas turbines, one of which is described herein.
Stresses and Strains in Cold-Extruding 2S-O Aluminum
Authors: Thomsen E. G. , Frisch J.
Published: July 2022

2S-O aluminum was extruded at room temperature in an inverted extrusion process from a 4.3-in-diam cylindrical billet, into a 1.5-in-diam solid cylindrical bar. Steady-state particle-velocity vectors were determined from gridded, split billets during incremental extrusion steps. These velocity patterns were compared with those obtained previously for lead extrusions having the same billet and die geometry and the same high degree of lubrication; it was found that the patterns for these two metals were identical. The aluminum velocity pattern appeared not to be affected by extrusion load, but the extrusion load was a strong function of the extent of deformation. It was estimated that the extrusion load becomes constant after a reduction of billet length by approximately 2.4 in., the distance the plastic zone of the metal extends upstream from the orifice. The axial-stress distribution in the billet, determined front strain rates and natural strains, taking into account work hardening, had the same shape as that determined with lead. The wall pressure or radial stress in the plastic zone was found to be lower than the average pressure, but both pressures tend to approach each other beyond the plastic zone.
The Free-Piston Type of Gas-Turbine Plant and Applications
Authors: McMullen J. J. , Ramsey R. P.
Published: July 2022

This paper is intended to set forth the latent possibilities in heavy-duty free-piston machinery. The cycle promises diesel efficiency from a simple low-temperature gas turbine having low first costs. Many features are described in the paper. Cooper-Bessemer has built a test plant and is now investigating its operating characteristics. No conclusions have been announced. Economic evaluations are being made requiring additional field work which includes an examination of the general acceptance by engineering and operating people who ultimately will decide the actual utility. Detailed cost studies of complete plants, including careful estimates of the machinery, have been made for electric power generation, pipe-line pumping, and marine installations. Some of these have been made available for use in this paper with the belief that such an evaluation of this prime mover will be of general interest to the Society.
The Application of Additives to Fuel Oil and Their Use in Steam-Generating Units
Authors: McIlroy J. B. , Holler E. J. , Lee R. B.
Published: July 2022

Ash deposits in steam-generating units have been becoming more troublesome and have presented a design and operating problem. It is recognized that troublesome deposits are characterized by a high content of low-temperature-melting constituents. This paper is concerned with the addition of high-temperature melting-point compounds to the fuel oil to elevate generally the melting point of the aggregate above the troublesome temperature level. Fusing temperatures of intimate mixtures of oil ash with many additive compounds were determined. Alumina was found to be the best material, with magnesium and calcium oxides showing promise. The fusing-temperature tests were substantiated by pilot-furnace-firing tests and these results in turn were applied to further experimentation on a full-sized unit. Alumina was the first additive used in a steam-generating unit of the Florida Power Corporation. Alumina was later replaced by dolomite. Both materials raised the fusing temperature of the ash to the extent that the work of removal was considerably decreased, but dolomite proved to be the most desirable from an operating as well as an economic standpoint. Other benefits, such as decreasing the acidity of the ash in the unit, were apparent when using dolomite. The use of the process is now being extended to other units. An arrangement of necessary equipment with detailed description of the components is appended.
Valve-Gear Fundamentals for the Large-Engine Designer
Authors: Newton J. A. , Allen C. H.
Published: July 2022

The poppet valves of any internal-combustion engine, large or small, receive specialized attention from designers as they frequently are the factor limiting the interval between engine shutdowns for overhaul. Although valves receive the brunt of the criticism, frequently the cause of the difficulty involves other parts associated with the valve system. For this reason, the authors’ company and other valve manufacturers have found it advisable to become intimately associated with design testing and research of the components found in conventional valve-gear systems. The purpose of this paper is to bring before the members of the large-engine industry fundamental information which may be of help in simplifying their valve-gear design problems.
Static-Flow Characteristics of Single and Two-Stage Spring-Loaded Gas Pressure Regulators
Authors: Iberall A. S.
Published: July 2022

A theoretical investigation of greater completeness than is usually presented has been made of gas pressure regulators. Emphasis has been placed on the application to their design. The analysis is summarized in graphical form in which the characteristics of the regulator may be obtained by ruler and compass constructions. Brief attention is given to the errors inherent in the simplifications made in the analysis.
Thermal Lags in Flowing Systems Containing Heat Capacitors
Authors: Rizika J. W.
Published: July 2022

The method of procedure to find the thermal lag in systems, such as heat exchangers and pipes, is shown and the case of the parallel flow heat exchanger is partially treated. The Laplace transformed solutions are presented. An equivalent treatment of the counterflow heat exchanger is given in the Appendix.
Tube Expanding and Related Subjects
Authors: Fisher F. F. , Brown G. J.
Published: July 2022

The paper summarizes experiences gained by expanding tubes into various types of powerhouse equipment and by the development of improved expanding tools and new rolling methods. Manual and controlled rolling methods are described and their relative merits discussed. Information is given relative to the making of rolled joints having optimum strength and stability. All subject matter is viewed and discussed from a practical standpoint and references are cited, if pertinent and available.
The New Kearny Generating Station: Public Service Electric and Gas Company
Authors: Fairchild F. P.
Published: July 2022

The author describes the more important features of the design of the new Kearny Generating Station and points out the significant differences between Kearny and Sewaren. Outstanding features are the steam conditions, 2350 psig, 1100 F–1050 F; pressurized firing of boilers; controlled circulation in boilers; gas recirculation; side-exhaust turbines with twin condensers and no expansion joint between turbine and condenser; an experimental high-speed boiler feed pump; and a completely austenitic main steam system.
An Experimental and Theoretical Investigation of Two-Dimensional Centrifugal-Pump Impellers
Authors: Acosta A. J.
Published: July 2022

An experimental and theoretical investigation on a series of two-dimensional centrifugal-pump impellers has been made in an effort to determine the usefulness of potential theory for the description of the flow. Computed values of the developed head and pressure distribution on the vane surfaces are compared with measurements on two, four, and six-vaned logarithmic spiral impellers. The agreement between the observed and predicted quantities is reasonably good for operating points where the influence of the inlet turn on the internal flow is least. The discrepancies which occur at other flow rates are attributed to real fluid effects which are observed in the impeller passages.
Grand Coulee Model-Pump Investigation of Transient Pressures and Methods for Their Reduction
Authors: Lindros E.
Published: July 2022

In May, 1951, when the first of six pumps ordered for the Grand Coulee Dam was put in service, a defect of major concern was discovered. This unfavorable condition embodied objectionable discharge-line vibration. Investigation revealed that this was caused by transient pressure variation in the pump, and remedial measures incorporating reinforcement of the discharge lines were taken to minimize this condition. No previous investigation had been made of the offending transient pressure variation. This paper describes such an investigation, the test setup used, and reveals the difficulty encountered in applying instrumentation to obtain necessary data.
Small Nozzles and Low Values of Diameter Ratio
Authors: Bean H. S. , Johnson R. M. , Blakeslee T. R.
Published: July 2022

In 1943 the National Bureau of Standards calibrated ten sets of nozzles for the Heat Exchange Institute, using adapters originally intended for open-inlet or discharge conditions, in a modified arrangement for in-line measurements. These calibrations were made with air. Since then, new adapters have been prepared to facilitate using them in the “in-line” manner. Two sets of the nozzles have been recalibrated using these new adapters and a weighed-water procedure. The results of these new calibrations are presented and a comparison made with the earlier results. For most of the nozzles, the agreement between the original air calibrations and the recent water calibrations is well within the range of experimental uncertainties.
Dynamic Characteristics of Valve-Controlled Hydraulic Servomotors
Authors: Shearer J. L.
Published: July 2022

A servomotor consisting of a valve-controlled ram connected to a mass plus viscous-friction load is analyzed on the basis of its response to small changes of valve position and external load force. The approach is sufficiently general to enable one to deal effectively with systems in which fluid compressibility is an important factor. At the same time, this approach is helpful in working with simpler systems. A functional block diagram is employed to delineate symbolically the significance of each system characteristic. A sample design problem is worked out to demonstrate how the material in this paper may be applied to a practical problem.
Contributions to Hydraulic Control—6: New Valve Configurations for High-Performance Hydraulic and Pneumatic Systems
Authors: Lee Shih-Ying
Published: July 2022

In high-performance hydraulic and pneumatic systems, three-way or four-way valves of very high precision are required. Conventional spool-type valves used for this purpose have been found to be difficult and expensive to manufacture. This paper describes a new type of metering orifice and several valve designs utilizing this metering orifice. These valves have proved to be considerably easier to make and more trouble-free than the piston-type design with the same performance. Flow-force-reduction methods for this type also are described. The work to be reported here was carried out at the Dynamic Analysis and Control Laboratory and was supported by the U. S. Navy Bureau of Ordnance Contract NOrd 9661 with the Division of Industrial Cooperation of the Massachusetts Institute of Technology.
Apparatus for Study of Effects of Cyclic Thermal Stresses on Ductile Metals
Authors: Coffin L. F. , Wesley R. P.
Published: July 2022

In cases in which very high rates of heat transfer exist, as in nuclear reactors, severe thermal stresses can be developed in structural metals. These stresses can be relieved by plastic flow and, consequently, are not regarded as serious when steady-state conditions prevail. Under the action of thermal oscillations, however, cyclic thermal stresses are developed. Depending on the frequency of thermal cycles and severity of the thermal stress, fatigue failure can result. Because of its low thermal conductivity and high thermal expansion, 18 per cent chromium-8 per cent nickel stainless steels are particularly prone to this effect. An investigation of this problem has been under way for some time. The object has been twofold: (a) To obtain information so that a particular material may be assessed critically for its resistance to thermal stress-fatigue damage under specified conditions, and (b) to investigate the fundamental aspects of the problem in order to learn more about the fatigue phenomenon. The paper describes the test apparatus developed for this study. A companion paper gives the test results to date and their interpretation.
Compressibility of Gases—VIII: Krypton in the Temperature Range 0 to 600 C and Pressure Range 10 to 80 Atm
Authors: Whalley E. , Schneider W. G.
Published: July 2022

The compressibility of krypton has been measured in the temperature and pressure range described.
Stress-Rupture Properties of Some Chromium-Nickel Stainless-Steel Weld Deposits
Authors: Wylie R. D. , Corey C. L. , Leyda W. E.
Published: July 2022

The use of higher steam temperatures in central-station generating plants has required the manufacturer of power-boiler equipment to use austenitic chromium-nickel steels for the outlet sections of the superheater where metal temperatures are in the order of 1200–1250 F. Since these tubular materials must be fabricated by welding, The Babcock & Wilcox Company has been conducting a test program on the high-temperature strength of chromium-nickel stainless-steel welded joints. The first work to be completed is data on the strength of all-weld-metal coupons of eleven compositions of commercial stainless-steel weld deposits. It is hoped that the data in this report, together with those presented in subsequent discussion by other industrial organizations, will serve as a guide to the Subcommittee on Stress Allowances for Ferrous Materials of the ASME Boiler Code Committee in the selection of allowable stresses for the chromium-nickel stainless steels.
Effect of Certain Elements on the Graphitization of Steel
Authors: Fiorentino R. J. , Hall A. M. , Jackson J. H.
Published: July 2022

An investigation was undertaken to obtain information on (a) the relationship, if any, between the aluminum and nitrogen contents of a steel and the susceptibility of the steel to graphitization, (b) the manner in which chromium influences the process, and (c) the effect of normal amounts of Mn, Si, S, and P in the graphitization of steel. Toward these objectives, twelve laboratory heats of iron-carbon alloy were made from specially prepared melting stock. Various amounts of Al, N, Cr, Mn, Si, S, and P were added to these heats. They were forged to ⅝-in-square bars, variously heat-treated, bead-welded, and tested for graphitization at 1025 F for periods of time extending to 8000 hr. Information on the progress of graphitization in the specimens was obtained by metallographic examination. The data obtained included the number of graphite nodules per unit area (as a measure of nucleation), the average nodule diameter, and the per cent conversion of carbide to graphite—all as functions of time. The evidence generally indicated that the graphitization process, whether occurring in the weld-heat-affected zone or in unaffected parent metal, took place by means of a nucleation and growth mechanism, which envisages a time rate of nucleation.
Frequency-Response Analysis and Controllability of a Chemical Plant
Authors: Aikman A. R.
Published: July 2022

The practical frequency-response analysis of two types of chemical-plant units, and the adjustment of the automatic controllers, are described. Available information on the magnitude, form, and location of disturbances is used to illustrate the effect of these factors on the quality of control actually obtained, and to emphasize that these factors are at least as important as the over-all characteristics of the plant. Even when all information on the disturbances is available, their effect on the quality of automatic control is not always easy to calculate, especially if the system has distributed parameters, but a description is given of an approximate calculation method which yields results of the right order of magnitude in many practical cases.
Frequency-Response Methods Applied to the Study of Turbine Regulation in the Swedish Power System
Authors: Oja V.
Published: July 2022

This paper describes principles worked out for the design of frequency-power regulation in a power system. The method of analysis is based upon general ideas of frequency-response methods and offers new possibilities for evaluating the regulation properties of power stations. It is aimed to give efficient regulation with the least possible effort. This is attained by matching the feedback data for the governors to the characteristics of the machines and the actual disturbances in the network. This method has been worked out for the Swedish power system. The power system is described briefly, the characteristics of the elements in the regulation loop are given, and the measurements of the frequency-response curve of the power system are reviewed.
Hollow cathode enhanced capacitively coupled plasmas in Ar/N2/H2 mixtures and implications for plasma enhanced ALD
Authors: Boris David R. , Johnson Michael J. , Eddy Charles R. , Walton Scott G.
Published: July 2022

Plasma enhanced atomic layer deposition (PEALD) is a cyclic atomic layer deposition process that incorporates plasma-generated species into one of the cycle substeps. The addition of plasma is advantageous as it generally provides unique gas-phase chemistries and a substantially reduced growth temperature compared to thermal approaches. However, the inclusion of plasma, coupled with the increasing variety of plasma sources used in PEALD, can make these systems challenging to understand and control. This work focuses on the use of plasma diagnostics to examine the plasma characteristics of a hollow cathode enhanced capacitively coupled plasma (HC-CCP) source, a type of plasma source that has seen increasing attention in recent years for PEALD. Ultraviolet to near-infrared spectroscopy as well as spatially resolved Langmuir probe and emissive probe measurements are employed to characterize an HC-CCP plasma source using nitrogen based gas chemistries typical of nitride PEALD processes. Spectroscopy is used to characterize the relative concentrations of important reactive and energetic neutral species generated in HC-CCP systems as a function of applied RF power, gas chemistry, and pressure. In addition, the electron energy distribution function, electron temperature, plasma potential, and plasma density for the same process parameters are examined using an RF compensated Langmuir probe and emissive probe. These measurements indicated that electron temperature (Te), electron density (ne), and plasma potential (Vp) varied significantly over the operating conditions examined with Te varying from 1.5 to 8 eV, Vp varying from 30 to 90 V, and ne varying between 1015 and low 1016 m−3. This wide range of plasma conditions is mediated by a mode transition from a low Te, high ne mode of operation at low pressure (<100 mTorr) to a high Te, low ne mode at higher pressures (>100 mTorr). These operational modes appear analogous to the classical γ and α modes of traditional capacitively coupled plasmas. Atomic N and H densities also vary significantly over the operating conditions examined.
Acoustics@Home: Laboratories and student-led projects conducted for an undergraduate engineering experimentation course during the COVID-19 pandemic
Authors: Lawless Martin S. , Giglia Michael , Wootton David M.
Published: July 2022

Hands-on, project-based learning was difficult to achieve in online classes during the COVID-19 pandemic. The Engineering Experimentation course at Cooper Union teaches third-year mechanical engineering students practical experimental skills to measure physical phenomenon, which typically requires in-person laboratory classes. In response to COVID, a low-cost, at-home laboratory kit was devised to give students tools to conduct experiments. The kit included a microcontroller acting as a data-acquisition device and custom software to facilitate data transfer. A speed of sound laboratory was designed with the kit to teach skills in data collection, signal processing, and error analysis. The students derived the sound speed by placing two microphones a known distance apart and measuring the time for an impulsive signal to travel from one to the other. The students reported sound speeds from 180.7–477.8 m/s in a temperature range from 273.7–315.9 K. While these reported speeds contained a large amount of error, the exercise allowed the students to learn how to account for sources of error within experiments. This paper also presents final projects designed by the students at home, an impedance tube and two Doppler shift experiments, that exhibit successful and effective low-cost solutions to demonstrate and measure acoustic phenomenon.
Molecular mechanism of
S
-adenosylmethionine sensing by SAMTOR in mTORC1 signaling
Authors: Tang Xin , Zhang Yifan , Wang Guanchao , Zhang Chunxiao , Wang Fang , Shi Jiawen , Zhang Tianlong , Ding Jianping
Published: July 2022

The mechanistic target of rapamycin–mLST8-raptor complex (mTORC1) functions as a central regulator of cell growth and metabolism in response to changes in nutrient signals such as amino acids. SAMTOR is an
S
-adenosylmethionine (SAM) sensor, which regulates the mTORC1 activity through its interaction with the GTPase-activating protein activity toward Rags-1 (GATOR1)-KPTN, ITFG2, C12orf66 and SZT2-containing regulator (KICSTOR) complex. In this work, we report the crystal structures of
Drosophila melanogaster
SAMTOR in apo form and in complex with SAM. SAMTOR comprises an N-terminal helical domain and a C-terminal SAM-dependent methyltransferase (MTase) domain. The MTase domain contains the SAM-binding site and the potential GATOR1-KICSTOR–binding site. The helical domain functions as a molecular switch, which undergoes conformational change upon SAM binding and thereby modulates the interaction of SAMTOR with GATOR1-KICSTOR. The functional roles of the key residues and the helical domain are validated by functional assays. Our structural and functional data together reveal the molecular mechanism of the SAM sensing of SAMTOR and its functional role in mTORC1 signaling.
Immunotherapy of glioblastoma explants induces interferon-γ responses and spatial immune cell rearrangements in tumor center, but not periphery
Authors: Shekarian Tala , Zinner Carl P. , Bartoszek Ewelina M. , Duchemin Wandrille , Wachnowicz Anna T. , Hogan Sabrina , Etter Manina M. , Flammer Julia , Paganetti Chiara , Martins Tomas A. , Schmassmann Philip , Zanganeh Steven , Le Goff Francois , Muraro Manuele G. , Ritz Marie-Françoise , Phillips Darci , Bhate Salil S. , Barlow Graham L. , Nolan Garry P. , Schürch Christian M. , Hutter Gregor
Published: July 2022

A patient-tailored, ex vivo drug response platform for glioblastoma (GBM) would facilitate therapy planning, provide insights into treatment-induced mechanisms in the immune tumor microenvironment (iTME), and enable the discovery of biomarkers of response. We cultured regionally annotated GBM explants in perfusion bioreactors to assess iTME responses to immunotherapy. Explants were treated with anti-CD47, anti–PD-1, or their combination, and analyzed by multiplexed microscopy [CO-Detection by indEXing (CODEX)], enabling the spatially resolved identification of >850,000 single cells, accompanied by explant secretome interrogation. Center and periphery explants differed in their cell type and soluble factor composition, and responses to immunotherapy. A subset of explants displayed increased interferon-γ levels, which correlated with shifts in immune cell composition within specified tissue compartments. Our study demonstrates that ex vivo immunotherapy of GBM explants enables an active antitumoral immune response within the tumor center and provides a framework for multidimensional personalized assessment of tumor response to immunotherapy.
Only pregnant moms can do it….
Authors: Pillai Shiv
Published: July 2022

During pregnancy, sialic acid on
Listeria monocytogenes
antibodies can be deacetylated, sanctioning these antibodies to mediate protection in the newborn.