bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporal cell wall changes during cold acclimation and deacclimation and their potential involvement in freezing tolerance and growth
Authors: Kutsuno Tatsuya , Chowhan Sushan , Kotake Toshihisa , Takahashi Daisuke
Published: December 2022

Plants adapt to freezing stress through cold acclimation, which is induced by nonfreezing low temperatures and accompanied by growth arrest. A later increase in temperature after cold acclimation leads to rapid loss of freezing tolerance and growth resumption, a process called deacclimation. Appropriate regulation of the trade‐off between freezing tolerance and growth is necessary for efficient plant development in a changing environment. The cell wall, which mainly consists of polysaccharide polymers, is involved in both freezing tolerance and growth. Still, it is unclear how the balance between freezing tolerance and growth is affected during cold acclimation and deacclimation by the changes in cell wall structure and what role is played by its monosaccharide composition. Therefore, to elucidate the regulatory mechanisms controlling freezing tolerance and growth during cold acclimation and deacclimation, we investigated cell wall changes in detail by sequential fractionation and monosaccharide composition analysis in the model plant Arabidopsis thaliana, for which a plethora of information and mutant lines are available. We found that arabinogalactan proteins and pectic galactan changed in close coordination with changes in freezing tolerance and growth during cold acclimation and deacclimation. On the other hand, arabinan and xyloglucan did not return to nonacclimation levels after deacclimation but stabilized at cold acclimation levels. This indicates that deacclimation does not completely restore cell wall composition to the nonacclimated state but rather changes it to a specific novel composition that is probably a consequence of the loss of freezing tolerance and provides conditions for growth resumption.
Patterning ecological restoration after weeds
Authors: Young Stephen L. , Hamerlynck Erik P.
Published: December 2022

The United Nations Decade on Ecosystem Restoration aims to prevent, halt, and reverse the degradation of ecosystems on every continent. Disturbances stemming from anthropogenic or natural causes make plant community restoration challenging. The introduction of fast‐growing weeds that generate high biomass and produce copious seed is most threatening to plant communities. A paradigm shift in ecosystem restoration is needed that emphasizes traits and affected ecological processes similar to weeds. The repeated introduction of seed from native plants with weedy characteristics follows the propagule pressure and evolution of invasiveness hypotheses. In targeting areas with heavy weed populations, native plants could establish and more successfully develop into functioning plant communities.
Theorizing surveillance and social spacingthroughfootball: The fan‐opticon and beyond
Authors: Turner Mark , Lee Ludvigsen Jan Andre
Published: December 2022

This article critically examines the temporal mobilizations of a 25‐year football supporter social movement against the all‐seating (stadia) legislation in England and Wales, to unpack, and advance, (neo‐)Foucauldian panoptic theorizations of surveillance power and counter‐power. Drawing upon prior empirically informed analysis of this movement; ‘Safe Standing’, the article interrogates new policy‐based outcomes, including the early adoption of ‘licensed (Safe) Standing’ technology in 2022, to argue, that whilst publicly framed as a movement victory, it simultaneously serves to prefigure a new regulatory regime in football; one which extends the regulation and surveillance of fans within the wider social and corporatelifeworld. Introducing our new concept; the ‘fan‐opticon’, the article discusses how Safe Standing continues to normalize a momentum of surveillance in sport and highlights the contradictory nature of security‐related projects in the twenty‐first century. We conclude that the governmentality of the state through football, to be characteristic of temporally sensitive hermeneutic struggles of power and resistance, through the discipline, and self‐discipline of social actors. New forms of subjectivity are remoulded in ways which extend the power of surveillance and regulation, despite multiple counter‐conduct, and discursive, resistance practices.
To stand in line and fit in—About military men's (un)reflected navigation in the armed forces
Authors: Linehagen Frida , Wester Misse
Published: December 2022

The purpose of the study is to investigate how the everyday experience of being a man in a male‐dominated organization and what navigating the organization is like. The study builds on 15 interviews with men of various ages and ranks in the Swedish Armed Forces. The findings revealed three major themes that illustrate how men, and their actions, contribute to producing and re‐producing gendered norms. First, the ideal military person is seen to have characteristics that are predominantly male and even though respondents only identify with these characteristics to some extent, the typical male ideal is still prevalent within the Armed Forces. Second, this image is reproduced by an uncritical stance towards the internal workings of the organization, relating to career paths and their reliance of traditional gendered roles. Third, the Armed Forces encounter resistance to gender equality work from within the military organization, in both action and inactions. We suggest this is due to a resistance to change and that work with gender equality is minimized to a shadow task that lacks committed men. We conclude that men's reality seems both obvious and unreflected, and these structures are upheld within the Armed Forces.
Validating the use of student‐level instruments to examine preservice teachers' mathematical problem solving
Authors: Folger Timothy D. , Stewart Maria , Bostic Jonathan , May Toni A.
Published: December 2022

Problem solving is a central focus of mathematics teaching and learning. If teachers are expected to support students' problem‐solving development, then it reasons that teachers should also be able to solve problems aligned to grade level content standards. The purpose of this validation study is twofold: (1) to present evidence supporting the use of the Problem Solving Measures Grades 3–5 with preservice teachers (PSTs), and (2) to examine PSTs' abilities to solve problems aligned to grades 3–5 academic content standards. This study used Rasch measurement techniques to support psychometric analysis of the Problem Solving Measures when used with PSTs. Results indicate the Problem Solving Measures are appropriate for use with PSTs, and PSTs' performance on the Problem Solving Measures differed between first‐year PSTs and end‐of‐program PSTs. Implications include program evaluation and the potential benefits of using K‐12 student‐level assessments as measures of PSTs' content knowledge.
Semantic integration of OpenStreetMap and CityGML with formal concept analysis
Authors: Ahmadian Somayeh , Pahlavani Parham
Published: December 2022

Volunteered geographic information (VGI) provides geometric and descriptive sources of geospatial data. VGI exchange, reuse, and integration are serious challenges due to the subjective contribution process, lack of organization, and redundancy. This study aims to enhance the quality of VGI semantic data by presenting a new approach to integrating and formalizing the VGI semantic knowledge using formal concept analysis. The proposed approach is assessed using the building tags in OpenStreetMap (OSM) and CityGML. The alignment process discovers the conceptual overlap between the categories of Amenity (Others), Office, and Man‐Made in Map Features (OSM) and Business and Trade, Recreation, Sport, and Industry in AbstractBuilding (CityGML). The k‐means clustering of the results illustrated that class, usage/function, address, wheelchair, and website/wikidata/wikipedia are significant attributes to describe building categories. Moreover, results showed that the analysis of frequent itemsets and cluster characteristics provides significant information about custom tags in OSM's editing tools.
Heat Transfer and Fluid Friction During Viscous Flow Across Banks of Tubes
Authors: Omohundro G. A. , Bergelin O. P. , Colburn A. P.
Published: December 2022

A co-operative program is in progress for the study of fluid friction and heat transfer in idealized models and in commercial tubular heat exchangers over a wide range of variables and under standardized conditions of equipment and technique. Suitable equipment for rapid and accurate testing of the models is described. Heat-transfer coefficients during cooling, and pressure-drop data during both isothermal and cooling runs are reported for low velocities chiefly in the region of viscous flow over an unbaffled tube bank. The data are plotted in ways previously used in the literature with fair agreement in most cases. It is expected, however, that when data for widely different conditions have been obtained, other methods of correlation may prove more suitable.
Motion Analysis of Several Intermittent Variable-Speed Mechanisms: Featuring Zero or Near-Zero Acceleration and Deceleration Conditions at Start and at End of Motion of Output Shaft
Authors: Talbourdet G. J.
Published: December 2022

The purpose of this paper is to present a description and analysis of several intermittent variable-speed devices in which former difficulties have been overcome. These changes have proved valuable in the design of turret-indexing mechanisms and in many other applications.
Railroad Passenger Comfort—Decibel Level
Authors: Jack W. A.
Published: December 2022

Improvement in comfort may be realized by lowering the noise level to which the passenger is subjected. The author outlines the scientific approach to the noise problem, giving the analytical formulas essential to its study. These principles are then applied to railroad transportation problems.
Truck Riding Comfort
Authors: Nystrom K. F.
Published: December 2022

The author feels that in creating luxurious passenger cars, economical limits have been exceeded by introducing costly, complicated, and over-engineered appurtenances. The same criticism applies to truck design. Excessive weight and complications militate against long life of truck and track, and maintenance costs are high. He analyzes the components of the truck and points out where improvements can be made, finally suggesting the characteristics of the passenger-car truck of the future.
Improved Techniques in the Study of Engine Firing Orders Using the Vectorscope
Authors: Dashefsky G. J.
Published: December 2022

The state of dynamic balance of an engine and the magnitude of minor orders of torsional vibration are greatly influenced by the firing sequence of the cylinders. Investigation of this problem requires the evaluation of large numbers of vector diagrams and is therefore adaptable to the use of the Vectorscope. This mathematical instrument automatically and rapidly adds vector quantities with about the same accuracy as a good graphical summation. The principle and operation of the Vectorscope and its application to the solution of various vector problems were given in an earlier paper. The present paper deals specifically with techniques involved in applying the Vectorscope to the study of firing orders. Methods are indicated whereby large numbers of firing orders may be examined expediently and rapidly.
Distribution of Heat Generated in Drilling
Authors: Schmidt A. O. , Roubik J. R.
Published: December 2022

The object of this investigation was to determine the amount of heat which goes into the workpiece, chips, and drill at different cutting speeds and feeds. A tubular test bar of extruded Dowmetal was used as the workpiece, thus making the cutting action of the drill similar to that of a single-point tool. The total heat, the heat in the chips, and the heat in the drill were measured separately in a calorimeter.
Two-Species Laminated Beams
Authors: Dietz A. G. H.
Published: December 2022

This paper sets forth the simple theory of two-species wooden beams incorporating high-strength heavy outer laminations or “flanges,” together with low-strength lighter cores into glued laminated members having high strength and high stiffness. Expressions for transformed section, ratio of core depth to over-all depth, and shear at the neutral axis are derived. A few beams made of Douglas-fir outer laminations, and No. 1 or No. 2 common eastern-spruce cores were tested and their strength properties determined. Their performance coincided quite well with that predicted by the theory. A “form factor” similar to that for wooden I-beams may be involved.
Influence of Steel Hardness in Face-Milling
Authors: Armitage J. B. , Schmidt A. O.
Published: December 2022

Face-milling tests are reported on seven different kinds of steels for power consumption and tool life at hardnesses of approximately 200, 300, and 400 Bhn. At any given hardness power requirements varied but little, but differences in tool life were considerably greater. Machining the workpiece at an elevated temperature was found to decrease the power required and permit good cutter life. When tool-life or production tests are not available, the hardness of steel can be taken as a guide in choosing preliminary values of cutting speed and feed.
A Reconsideration of Deformation Theories of Plasticity
Authors: Drucker D. C.
Published: December 2022

Deformation theories of plasticity for strain-hardening materials are defined as those which postulate that the components of elastic and permanent strain are completely determined by the existing components of stress. The assumption is made that there is some criterion, in terms of stress, for loading or increase in plastic deformation. A common supposition of this nature is that the permanent strain will increase when the octahedral shearing stress increases.

It is shown that no matter what the loading criterion these deformation theories of plasticity lead to the unacceptable conclusion that large (finite) changes in the components of permanent strain may accompany infinitesimal increases in loading despite strain hardening. Simple illustrations are given and it is demonstrated that an incremental, or so-called flow theory eliminates this undesirable feature.
The Mechanical Seal—Its Construction, Application, and Utility
Authors: Schmitz C. E.
Published: December 2022

This paper outlines important construction features of the mechanical seal; discusses speed, pressure, temperature, and viscosity; application considerations, advantages, and when special construction is desirable; utility of the mechanical seal; and suggested services.
Calibration of Eccentric and Segmental Orifices in 4 and 6-In. Pipe Lines
Authors: Beitler S. R. , Masson D. J.
Published: December 2022

This is a preliminary report of a Subcommittee on Eccentric and Segmental Orifices of the Special Research Committee on Fluid Meters on the Calibration of Eccentric and Segmental Orifices. It describes the method used in calibrating orifices in 4 and 6-in. pipe lines and gives the results of the calibration which are available at this time. This program is only in its early stage and as a result, about 50 per cent of the work has been done.
Reaction Tests of Turbine Nozzles for Supersonic Velocities
Authors: Keenan J. H.
Published: December 2022

A machine for testing turbine nozzles by the reaction method, which was described in a previous paper, was used to test a series of convergent-divergent turbine nozzles. The results of these tests, along with the test of a convergent turbine nozzle, are compared with each other and with analytical values. Two kinds of analytical values are employed, namely, the usual values obtained from an assumed isentropic expansion from inlet state to exhaust pressure, and the values obtained from the assumption that the processes in the nozzle are isentropic except for a normal shock which takes up a position in the nozzle such as to cause the stream to fill the exit area at the exhaust pressure whenever possible. This latter kind of analytical value involves no shock when the exit area can be filled at the exhaust pressure by means of isentropic processes only, or when the exhaust pressure is lowered so far that the shock has passed out of the passage. The agreement of the test results with the calculated results of this latter kind is good, and the disagreement which exists can be attributed largely to separation at the shock and to transmission of exhaust-pressure effects upstream through the boundary layer.
The Physical Properties of Air With Reference to Meteorological Practice and the Air-Conditioning Engineer
Authors: Sheppard P. A.
Published: December 2022

The paper summarizes numerical values of physical functions and constants, relating to dry and moist air, of common use in meteorology and of interest to the air-conditioning engineer, and definitions and specifications of water vapor in the atmosphere.
Modern Control Dynamics and Stability Criteria as Applied to Gyroscopic Speed Detectors With Hydraulic Drive
Authors: Feiss Rene
Published: December 2022

A gyroscopic speed detector is described and its application to the speed control of a steam or gas turbine is discussed. A frequency-response method of analysis of regulatory systems, involving the use of Nyquist’s criteria, is presented and applied to the analysis of the stability of the turbine-speed regulatory system. The results obtained are compared with results from the classical approach, involving the solution of the characteristic equation of motion of the system.
Symposium on Development of Emergency Power Plants for Tanks
Authors:   Oil and Gas Power Division
Published: December 2022

A job to do and no time in which to do it! This was the problem that faced General Motors, Chrysler, and Ford back in 1941 when they were requested to furnish suitable power plants for land tanks that would utilize existing manufacturing facilities for immediate production.
General Motors Two-Cycle Diesel Engines for Ordnance Vehicles
Authors: Shoemaker F. G.
Published: December 2022

During the war General Motors supplied a large number of Diesel engines of its prewar automotive type for use in tanks, tractors, and other ordnance vehicles for both the United States and the British Armed Forces. At the same time a number of experimental engines and installations were made as a part of the forward-looking program of the Ordnance Department. These various engines are described briefly and a number of the engineering problems are discussed in some detail as an indication of the nature and magnitude of such industry-ordnance co-operative programs.
Unified Symbolism for Regulatory Controls
Authors: Philbrick G. A.
Published: December 2022

Following an exposition of its purposes and scope, this paper proceeds to develop and to apply its proposals for symbolism in the course of a somewhat novel reconstruction of the fundamentals of automatic regulation. It presents the basic null-seeker or follower, to which the more elaborate examples are shown subsequently to reduce, as a primary mechanism about which the symbolic and terminological structures of the subject may be centered. The manner in which regulatory controls are apt to be connected to otherwise unregulated systems is considered, along with a demonstration of the thoroughly distinct technique of compensation. Specific symbols are recommended, together with their self-explanatory names, for the functional elements and the variable quantities which are involved in such controls. There is also included a brief treatment of the relationship between the viewpoints of transient phenomena and steady oscillations, where these are concerned with a study of the dynamics of regulatory processes.
Latest Developments in Aircraft Controls and Instrumentation
Authors: Brown R. A.
Published: December 2022

As the complications of operation on modern aircraft have increased, the provision of automatic controls has become a necessity to relieve the pilot and other operating personnel of the strain of continual manual control throughout flight periods. Electrical, pneumatic and hydraulic devices have been developed to accomplish reduction in manual functions but these must be controlled automatically by sensing elements which react to conditions encountered. Details of a basic control system having many and varied applications are cited in this paper.
Trends in Development and Application of Cutting Fluids
Authors: Beard J. T.
Published: December 2022

Beginning with the cutting fluids that were commonly employed 30 or 40 years ago, such as lard oil, straight mineral oil, soda water, and soap water, the author traces the development of cutting fluids through the mineral-lard oils, the sulphurized mineral oils, the sulphurized fat bases, the various chlorinated additives to the synthetic additives of the present day. This paper deals with the influence that various metals have upon the types of cutting fluids which are used, and especially on the role played by the hardness and cutting qualities of metals. Some attention is given to the various groups of cutting tools, and how the selection of cutting fluids is governed to a large extent by the duties they perform. The part that is played by the design of machine tools is also discussed. Consideration is given to the new nonpetroleum grinding compounds which are beginning to make their appearance.
Experiences With Automatic Air Soot Blowers at the Oswego and Charles R. Huntley Steam Stations
Authors: Smith H. L.
Published: December 2022

This paper relates in some detail the experience obtained with full-automatic air soot-blowing equipment installed as the cleaning equipment for the external surfaces of three large pulverized-fuel-fired steam generators. It contains a brief description of the blowing equipment, compressors, and automatic controls; information of general interest as to the actual operating performance; and the relative installed cost and investment as compared to comparable steam equipment.
Three Systems for Handling and Storing Metal Chips
Authors: Reibel S.
Published: December 2022

Great advances have occurred during recent years in methods of disposing of metal chips from machining operations. Without the knowledge and equipment to implement it, serious production curtailments would have taken place during the war. What was learned then of chip-handling methods and salvage of useful material may now be applied to peacetime production. The author describes an aluminum-chip pneumatic handling and carloading system; a mechanical method of disposing of steel chips and turnings; and a new system of mechanical handling with gravity carloading features.
Diesel Combustion Temperatures—The Influence of Operating Variables
Authors: Uyehara O. A. , Myers P. S. , Watson K. M. , Wilson L. A.
Published: December 2022

Flame-temperature data obtained with the electro-optical pyrometer developed at the University of Wisconsin, and performance curves showing the influence of operating variables are presented. Unique contour graphs show combustion characteristics in a form that facilitates visualization of the existing relationships. Observed combustion trends are pointed out and discussed.
Temperature Distribution in White-Oak Laminated Timbers Heated in a High-Frequency Electric Field
Authors: Dunlap M. E. , Bell E. R.
Published: December 2022

High-frequency dielectric heating has been applied to the process of laminating commercial white-oak ship timbers. Specimens 6 × 6 × 24 in., composed of eight laminations ¾ × 6 × 24 in., were heated both with and without glue to study the temperatures obtaining in the glue-line areas. The uniformity of temperatures depends upon the density, moisture content, and arrangement of the laminations, direction of the electric field, and thermal insulation of the heated material. The effect of these variables is greater when the electric field and glue lines are parallel than when they are mutually perpendicular. Thermocouples were used for rapid temperature measurement. A method of heating the sides of timbers effectively was developed.
Clogging of Bituminous Coal in Bunkers
Authors: Legget R. F.
Published: December 2022

Flow of bituminous coal out of the reinforced-concrete bunkers of the Polymer Corporation’s steam power plant at Sarnia, Ontario, was found to be impeded by clogging of the coal. Study of the problem by means of a series of tests in a model bunker eliminated a number of suggested causes, showing finally that the clogging was determined by the moisture content of the coal. Ways of controlling the moisture content below the critical value are suggested.
Nickel-Chromium Alloys for Gas-Turbine Service
Authors: Crawford C. A.
Published: December 2022

The author describes two interesting nickel-base alloys developed with properties useful for gas-turbine applications at temperatures up to at least 1500 F. The first of these alloys, Inconel X, is a wrought material, readily forged and welded, with high rupture strength at all temperatures up to 1500 F and possibly higher. In addition to its use in gas turbines, Inconel X appears to offer promise as a spring material operating at temperatures of 900 F or more. The material has also been supplied experimentally in sheet form for aircraft manifold assemblies, tail pipes, and similar components. It has been produced commercially in ingot sizes as large as 5000 lb and is available in billets, simple rod sections, wire, sheet, and strip and may soon be available in tubing form. The second of the two alloys is a cast material primarily suited for extended service applications requiring high creep resistance in the neighborhood of 1500 F. The alloy has good casting qualities and is resistant to thermal shock, thereby making possible the use of high-temperature heat-treatment.
Determination of the Thermal Correction for a Single-Shielded Thermocouple
Authors: Rohsenow W. M. , Hunsaker J. P.
Published: December 2022

Previously lacking a satisfactory technique for measuring the temperature of a hot gas stream, a single-shielded thermocouple has been developed which, while entirely practical, requires a thermal correction when being applied. A rapid graphical method of determining this correction and its magnitude in relation to some thermocouple designs is outlined.
Kinematics of Disk Cam and Flat Follower
Authors: Candee Allan H.
Published: December 2022

This paper demonstrates the practicability of determining the proper shape of a cam to produce a required motion by means of what might be termed “geometrical kinematics.” The author shows how the general principles of geometry and kinematics can be applied and that the graphical method is not limited to determining a cam profile as the envelope of the follower. The methods of kinematics, including graphical construction, can determine points of contact and centers of curvature, so as to avoid cusps. Dimensions of the cam can be obtained to any desired degree of accuracy by calculations based upon the geometrical constructions. Designers and draftsmen will find the methods explained easy to understand and use.
Evaporation-Cooling for Pure-Water Systems for Turbine-Generator Gas and Oil Coolers
Authors: Knowlton P. H.
Published: December 2022

Two systems of evaporation-cooling for condensate to be circulated through generator and lubricating-oil coolers on steam turbines are described, and charts provided to facilitate certain calculations to determine the operating power required and consequent losses or gains to the steam cycle. An example of each system has been worked out, each with two different steam-pump efficiencies. A few comments have been made regarding the possibilities of design of suitable steam pumps. There seems to be no reason why such systems could not be designed and operated satisfactorily. No attempt has been made to compare these evaporation systems with other methods of doing the cooling. The author considers that power-plant engineers and operators are in a much better position than he to offer informed opinions of such comparisons. It seems evident that whenever the condensate from the condenser is cool enough to be used directly, there is no reason to consider the evaporation systems. It is possible that one of the two evaporation-cooling systems may compare favorably with the use of raw-water or raw-water-to-condensate heat exchangers when the condensate temperature is too high to be used directly.
Regeneration of Spent Catalyst in Fluid Catalytic Cracking
Authors: Snuggs J. F.
Published: December 2022

The factors which influence the design, operation, and control of spent-catalyst regeneration facilities in commercial fluid catalytic cracking are discussed. The regeneration of spent cracking catalyst is accomplished by burning about 1 to 2 weight per cent of carbonaceous material from the catalyst under closely controlled operating conditions. During the combustion a large quantity of heat is produced. Regeneration supplies a portion of the heat required to support the reaction in the catalytic conversion zone, and excess heat is used to produce steam. A description of the facilities used for regeneration, and of the integration of these facilities with the rest of the catalytic plant is presented.
Bending Rigidity and Column Strength of Thin Sections
Authors: Sandorff P. E.
Published: December 2022

It has been found that elementary structural theory cannot be applied with accuracy to problems concerning beams and columns having thin deep webs and thin wide flanges, because of nonuniform stress distribution which exists in the flanges. In this paper the problems of nonuniform axial flange stress are treated by means of efficiency factors which apply to the flange material. These basic factors are evaluated from theoretical considerations. Then, given a particular section and the manner of loading, it is necessary only to apply the proper flange efficiency factor to calculate reduced or effective section properties, which can be used in place of the geometrical properties in the elementary formulas for lateral bending or lateral column buckling.

The results are substantiated by empirical data. Practical usage is illustrated with examples. The tangentmodulus column curve is shown to apply to stiffened-skin panels when based on a “true slenderness ratio” which allows for shear lag effects. Conclusions are drawn indicating design for best efficiency.
Experimental Study of Cylindrical Grinding
Authors: McKee R. E. , Moore R. S. , Boston O. W.
Published: December 2022

This paper, the second in a series on cylindrical grinding, presents some of the results of an investigation of the grinding process with particular reference to the influence of certain variables, such as table-traverse feeds, depths of cut, wheel grain and grade, and type and concentration of cutting fluid.
Semiuniversal Toothed Couplings
Authors: Wildhaber Ernest
Published: December 2022

The present analysis shows that tooth crowning is essential to keep the geometrical tooth contact within the boundaries of the tooth surfaces. Crowning in the axial direction also makes the transmitted motion more nearly uniform and increases the number of teeth in simultaneous contact. When properly designed, the coupling may transmit more nearly uniform motion than Hooke’s joint, but it does so in the manner of gears. Tooth contact is in two diametrically opposite zones of mesh. The theoretical departure from uniform motion increases with the square of the shaft angularity, and the number of simultaneously contacting teeth and the load capacity are correspondingly decreased. Semiuniversal toothed couplings give excellent results at small shaft angularities, where they combine simplicity and strength.
Explanation of Longitudinal Shrinkage of Wood Based on Interconnected Chain-Molecule Concept of Cell-Wall Structure
Authors: Cockrell R. A.
Published: December 2022

This paper demonstrates that the following four factors exert a significant influence on the longitudinal shrinkage-moisture content relationship of wood: (a) The interconnection of chain molecules; (b) fibril angle; (c) the cellulose chain-molecule length; (d) the microcapillary width. A mathematical demonstration is given to check the validity of the shrinkage theory advanced.
Temperature Distribution in Cylinder Heated by Point Source Moving Along Its Axis
Authors: Rosenthal D. , Cameron R. H.
Published: December 2022

The subject treated in this paper forms a part of a more general theory of heat flow involving moving sources of heat. The present problem deals with the temperature distribution around a point source moving at a constant speed along the axis of a cylinder. It is shown that the rise of temperature produced at a given cross section of the cylinder, as a result of the passage of the heat source, tends rapidly to become constant. The factor which governs this trend is a dimensionless product of the following units: (1) The speed at which the source travels; (2) the radius of the cylinder; and (3) the converse of the heat diffusivity.
An Investigation of Boiler-Drum Steel After Forty Years of Service
Authors: Blumberg H. S. , Smith G. V.
Published: December 2022

Examination of materials from seven riveted boiler drums removed from service after forty years’ operation at a temperature and pressure of 388 F and 200 psi has revealed no evidence of deterioration in the properties of the steel from which they were made.
The Proficorder—An Instrument for Recording Waviness and Other Surface Profiles
Authors: Abbott E. J. , Rupke Edward
Published: December 2022

The Proficorder described in this paper represents a major addition to available surface-measuring instruments. It provides data which are highly essential in the study of surfaces and the processes by which they are obtained. Its function is to reproduce, with appropriate magnifications, the actual profile of a considerable length of surface. It permits the study of individual irregularities as to size, shape, and relative position with respect to other irregularities. The instrument can be used to good advantage for inspection of production setups for waves and other surface characteristics. As an instrument for use in process engineering, it provides quantitative data for determining the effectiveness of steps taken to improve or obtain certain surface finishes in machining or grinding operations. As a laboratory instrument, the Proficorder supplies indispensable information to all those who are interested in determining the causes, effects, and characteristics of surface irregularities.
Development of an Air-Operated Force-Measuring System
Authors: Markson A. A. , Williams R. S.
Published: December 2022

The force-measuring system described in this paper depends upon the principle of using a nonmetallic flexible diaphragm as a null-deflection frictionless measuring piston. This is accomplished by use of a simple auxiliary positioning pneumatic-relay system. A novel viscous stabilizing damper is described. The paper outlines the industrial development of this principle. Previous related NACA work in this field is cited. Because the devices are now used in test measurements on cradle dynamometers, turbojet engines, rockets, and guided missiles, some essential data relating to the evaluation of such a system and its probable errors are given. It is shown that this principle is capable of yielding an unusually good combination of ruggedness and stable accuracy.
Measurements of Combined Frictional and Thermal Behavior in Journal-Bearing Lubrication
Authors: McKee S. A. , White H. S. , Swindells J. F.
Published: December 2022

Data were obtained in tests with a four-bearing friction machine which show that an increase in the load on a journal bearing produces a proportional increase in frictional torque when other conditions of test are held constant. Under these same conditions an increase in load also produces a proportional increase in the fluidity of the oil in the bearing. These two effects are the result of the combined hydrodynamic and thermodynamic actions involved in journal-bearing operation with forced-feed lubrication. The increase in torque is influenced by the viscosity of the oil, the oil-inlet temperature, the oil-feed pressure, the shaft diameter, the clearance-diameter ratio, and the length-diameter ratio. The increase in fluidity is influenced by the same factors and also by the speed of the journal. Empirical equations are derived for the fluidity-pressure relationship for certain conditions. Also, a graphical method is given for the use of this relationship in estimating safe bearing loads.
Power Turbines for Natural-Gas Expansion
Authors: Bencze Stephen
Published: December 2022

Natural-gas expansion turbines are driven by gas in the same way that steam drives steam turbines. These gas-expansion turbines are supplied with energy in the form of heat energy in the gas, and they convert this into useful mechanical energy. Turbines of this type are not to be confused with the combustion type of gas turbine in which the fuel is burned and the resultant gases allowed to expand, generating power, then exhausted and thrown away. In a natural-gas turbine, the gas is allowed to expand and is exhausted into subsequent processes and may be used for combustion or chemical reduction. The gas undergoes only a change in pressure and temperature and undergoes no chemical change in passing through the turbine. Thus the conversion of power can be considered a “by-product” to the normal uses of the gas.
III—Heats of Formation and Chemical Thermodynamic Properties
Authors: Rossini Frederick D.
Published: December 2022

This report describes the tables of selected values of chemical thermodynamic properties issued by the National Bureau of Standards and presents a summary of values of the heats of formation of the molecules H2O, CO, CO2, CH4, C2H4, NH3, and the atoms O, H, N, C, all in the gaseous state.
V—Vapor Pressure, Specific Volumes, and p-v-T Data for H2O, NH3 CH4, C2H4 With Comments on Mixtures
Authors: Keyes F. G.
Published: December 2022

Because of its importance wherever thermodynamics is used, reference is made to the need of improved knowledge of the relation of the international scale of 1927 to the thermodynamic scale. The published results of James A. Beattie comprise comparisons between the scales from 32 F to 832.28 F and indicate that the thermodynamic-scale temperature as a maximum is 0.26 deg F greater than the international scale at about 750 F. The new thermometric information makes possible a thermodynamic consistency test of vaporization data, vapor pressures, and volume data from the steam investigation sponsored by this Society up to 1935. It is suggested that additional volume data are desirable above 860 F. Comments are offered on the known thermodynamic properties of water, ammonia, methane, ethylene, and mixtures of a number of the eleven pure gases of the list selected by the Research Committee on Properties of Gases and Gas Mixtures.
VIII—Brief Review of Available Data on the Dynamic Viscosity and Thermal Conductivity for Twelve Gases
Authors: Hawkins G. A.
Published: December 2022

A brief review of the available data relative to the dynamic viscosity and thermal conductivity for twelve gases is presented in order to show the need for future experimental work. The values found in the survey for the thermal conductivity and viscosity for the various gases at a pressure of approximately 1 atm have been analyzed and average values presented in the form of graphs to show the influence of the temperature.
Instrument-Gear Standards and Design
Authors: Kuntny G. W.
Published: December 2022

Common gear formulas alone do not guarantee smooth, continuous, and uniform gear motion. Refinements and corrections on basic dimensions are sometimes needed. Small pinions, for example, must be made oversize with increased pitch diameters if weak undercut teeth and loss of overlapping tooth action are to be avoided. Accurate mathematical analysis of gear problems can be made by methods developed through the new science of gearing, “involute trigonometry.” Graphic gear analysis can be used to visualize gear theory and to double-check mathematical analysis. A fairly accurate graphic check can be made of essential gear elements such as overlapping tooth action, backlash, tolerances, and possible interference by duplicating the action of a gear-hobbing machine on a simple fixture described in this paper. Because accurate gear calculations are complex, the establishment of pre-selected standard specifications is recommended for frequently used classes and grades of gears. Samples of such “quick-reference” tables are included. They are intended as a timesaver for the busy designer, and as a yardstick of gear quality for the less experienced draftsman.
Development of a High-Speed Lathe for Machining Aluminum
Authors: Templin R. L.
Published: December 2022

This paper describes an experimental high-speed lathe, having a maximum spindle speed of 9000 rpm, capable of taking a 2¼-in-diam bar through its hollow spindle, driven by a special 80-hp motor; together with certain accessory equipment. Certain machining experiments conducted with the lathe on two aluminum alloys at cutting speeds varying from 5000 to 20,000 fpm are described.
Theory and Practice of the Crush-Dressing Operation on Grinding Wheels
Authors: Helfrich E. C.
Published: December 2022

This paper presents a qualitative analysis of the crush-dressing process based upon experimental evidence. The theory developed herein accounts for the forces involved, power requirements, rate of wheel removal, the effect of wheel and crusher diameters, and surface speed on the crushing process. The equations and data presented will enable the designer to engineer crush-dressing applications more intelligently, and will contribute to a clearer understanding of the process by all who may be interested in applying it. The advantages and disadvantages of crush-dressing versus diamond-truing are discussed with reference to the physical properties of crystals.
Heat Transfer Through Thick Insulation on Cylindrical Enclosures
Authors: Nickerson T. S. , Dusinberre G. M.
Published: December 2022

A graph is presented for finding the heat transfer through relatively thick insulation applied to an enclosure having the form of a short cylinder such as a tank. Incorrect treatment of the corner effect in this case may lead to serious error. The “relaxation” method of calculation was used.
A Method of Correlating Axial-Flow-Compressor Cascade Data
Authors: Davis Hunt
Published: December 2022

This paper describes a method of correlating wind-tunnel tests on axial-flow-compressor cascades. The use and construction of two charts for the NACA four-digit airfoil series are described. The charts relate the three cascade quantities; camber, solidity, and stagger angle with two flow angles; the entrance angle, and the turning angle, for low Mach numbers. When four of these five variables are given, the fifth is determined. A simple computation procedure to correct the solution for a high subsonic Mach number is given. The profile drag does not enter the correlation scheme directly but an approximate guide is indicated on the charts.
Effective Thermal Conductivity Model of Micron Hollow Sphere or Phase Change Material/Opacifier-SiO2 Aerogel Composites
Authors: Pang Hao-Qiang , Fan Ting-Hui , Zhang Sheng-Nan , Gao Yan-Feng
Published: December 2022

Pure SiO2 aerogel has a strong light transmittance in the infrared wavebands from 3.0 to 8.0 μm, and an opacifier could efficiently reduce aerogel's radiative thermal conductivity (λr), especially at high temperatures (>400 K). Consequently, the λr of different core/shell structured opacifiers is proposed, including micron hollow sphere opacifier (MHSOP), i.e., hollow carbon black/SiC/TiO2, and phase change material (PCM)/opacifier, i.e., VO2/SiO2, and Ge2Sb2Te5/SiC; further, their conductive λ model has also been established. The results showed that MHSOP could reduce MHSOPs-SiO2 aerogel composite's λ compared to traditional solid structure opacifiers; the effect of MHSOPs with a certain core–shell ratio on suppressing thermal radiation is equivalent to their solid structure opacifier at high-temperature. Adding SiC MHSOPs reduces aerogel composites' weight and thermal conductivity by 42.19 and 26.29%, while the shading effect of a core–shell ratio of over 0.75 is equivalent to the solid structure. Specifically, rutile-phased VO2/SiO2's λr is smaller than TiO2 MHOSP, and crystalline Ge2Sb2Te5/SiC doped aerogel exhibits good thermal insulation. The proposed micron hollow sphere opacifier and PCM/opacifier provide a novelty, lightweight, and high-efficiency method to restrain aerogel's infrared radiation and improve insulation performance at high temperatures.
Fluid Flow and Heat Transfer Characteristics of the Full-Scale Infrared Suppression Device With the Louvered Conical Funnels Considering Surface Radiation: A Three-Dimensional Numerical Analysis
Authors: Mukherjee Arnab , Chadrakar Vikrant , Senapati Jnana Ranjan
Published: December 2022

The current analysis examines the thermofluid properties of an infrared suppression (IRS) system with louvered conical diathermic funnel walls in the presence of surface radiation. An IRS device's flow and heat transfer characteristics are challenging because cold atmospheric air is entrained through the interfunnel openings into the IRS and mixes hot exhaust gas from the turbine in naval/cargo ships. The full Navier–Stokes equation is solved along with the energy equation and radiative transfer equation (where applicable) for modeling a three-dimensional actual-scale IRS device with louvered conical funnel walls. This study elucidates the influence of the Reynolds number (6.1×105 to 3.18×106) nozzle overlapping, inclination angle, funnel overlapping, and guide vanes on the air intake and system exit temperature. The calculation of the lock-on range on the ship with or without the IRS device. The performance of a diathermic wall with surface radiation is significantly improved.
Probes for Contemporary Measurement of Thermal Conductivity, Thermal Diffusivity, and Convection Heat Transfer
Authors: Corasaniti S. , Coppa P. , Potenza M. , Bovesecchi G.
Published: December 2022

Four probes for measuring thermal conductivity, thermal diffusivity, and convection heat transfer coefficient were designed, built, and tested. In two of these probes (SP-1 and SP-2), three thermocouples were placed at 25%, 50%, and 75% of the total length of 150 mm, while the third probe (SP-3) has the three thermocouples at 10%, 50%, and 90%. The fourth probe (DP-1) is a dual-probe, to measure thermal diffusivity using the pulse method. First results show good performance of the devices when measuring a reference material (glycerol). In fact, an accuracy of about ±5% was achieved in both thermal conductivity and thermal diffusivity measurements. The size of the probes (length 150 mm, diameter 2 mm) makes them particularly suitable for measuring the thermophysical properties of bulk materials, such as soils, composites, buildings walls, etc. Thanks to the presence of three thermocouples, convection can be studied so that also the boundary layer can also be evaluated.