bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased risk of functional neurological disorders following SARS‐CoV‐2 vaccination
Authors: Pilotto Andrea , Catania Marcello , Mattioli Irene , Zoppi Nicola , Ceccardi Giulia , Rao Renata , Gipponi Stefano , Magoni Mauro , Gamba Massimo , Padovani Alessandro
Published: January 2024

Background and purpose

The purpose of this study was to evaluate the possible correlation between SARS‐CoV‐2 vaccines and the onset of neurological syndromes. The aim was to challenge the association between SARS‐CoV‐2 vaccinations and the onset of acute functional neurological disorders (FNDs) compared to other neurological syndromes in hospitalized patients.

Methods

In this prospective cohort study, all adult inpatients consecutively admitted to a tertiary neurological centre were included. The prevalence and characteristics of neurological syndromes were compared between unvaccinated and vaccinated cases stratified according to the onset from vaccination. The study involved 843 subjects, namely 411 unvaccinated (UVC) and 432 vaccinated cases; these groups were comparable for demographics and clinical diagnosis distribution.

Results

Compared to UVC, subjects hospitalized within the first 30 days from vaccine exhibited higher prevalence of FNDs (12.3% vs. 3.6%; odds ratio 4.2, 95% confidence interval 1.6–11.1) and headache (10.8% vs. 5%; odds ratio 4.1, 95% confidence interval 1.9–8.8) but no other neurological syndromes. The FND cases following vaccinations showed similar premorbid conditions and severity but a higher percentage of sensory symptoms and pain compared to UVC FND cases.

Conclusions

SARS‐CoV‐2 vaccination is associated with a significant short‐term increased risk of FND and headache requiring hospitalization in an acute neurological setting.
Small but mighty: Peptides regulating abiotic stress responses in plants
Authors: Datta Tapasya , Kumar Ravi S. , Sinha Hiteshwari , Trivedi Prabodh K.
Published: January 2024

Throughout evolution, plants have developed strategies to confront and alleviate the detrimental impacts of abiotic stresses on their growth and development. The combat strategies involve intricate molecular networks and a spectrum of early and late stress‐responsive pathways. Plant peptides, consisting of fewer than 100 amino acid residues, are at the forefront of these responses, serving as pivotal signalling molecules. These peptides, with roles similar to phytohormones, intricately regulate plant growth, development and facilitate essential cell‐to‐cell communications. Numerous studies underscore the significant role of these small peptides in coordinating diverse signalling events triggered by environmental challenges. Originating from the proteolytic processing of larger protein precursors or directly translated from small open reading frames, including microRNA (miRNA) encoded peptides from primary miRNA, these peptides exert their biological functions through binding with membrane‐embedded receptor‐like kinases. This interaction initiates downstream cellular signalling cascades, often involving major phytohormones or reactive oxygen species‐mediated mechanisms. Despite these advances, the precise modes of action for numerous other small peptides remain to be fully elucidated. In this review, we delve into the dynamics of stress physiology, mainly focusing on the roles of major small signalling peptides, shedding light on their significance in the face of changing environmental conditions.
Untargeted metabolomics reveals PTI‐associated metabolites
Authors: Muñoz Hoyos Lina , Anisha Wan Petra , Meng Chen , Kleigrewe Karin , Dawid Corinna , Hückelhoven Ralph , Stam Remco
Published: January 2024

Plants employ a multilayered immune system to combat pathogens. In one layer, recognition of Pathogen‐ or Microbe‐Associated Molecular Patterns or elicitors, triggers a cascade that leads to defence against the pathogen and Pattern Triggered Immunity. Secondary or specialised metabolites (SMs) are expected to play a role, because they are potentially anti‐fungal compounds. Tomato (Solanum lycopersicum) plants inoculated with Alternaria solani s.l. show symptoms of infection after inoculation. Plants inoculated with Alternaria alternata remain symptomless. We hypothesised that pattern‐triggered induction of resistance related metabolites in tomato contributes to the resistance against A. alternata. We compared the metabolomic profile (metabolome) of tomato after treatments with A. alternata, A. solani and the fungal elicitor chitin, and identified SMs involved in early defence of tomato plants. We revealed differential metabolome fingerprints. The composition of A. alternata and chitin induced metabolomes show larger overlap with each other than with the A. solani induced metabolome. We identify 65 metabolites possibly associated with PTI in tomato plants, including NAD and trigonelline. We confirm that trigonelline inhibits fungal growth in vitro at physiological concentrations. Thus, a true pattern‐triggered, chemical defence is mounted against A. alternata, which contains anti‐fungal compounds that could be interesting for crop protection strategies.
ZmC2H2‐149 negatively regulates drought tolerance by repressing ZmHSD1 in maize
Authors: Liu Huafeng , Wu Zhendong , Bao Miaomiao , Gao Fengran , Yang Wenjing , Abou‐Elwafa Salah Fatouh , Liu Zhixue , Ren Zhenzhen , Zhu Yingfang , Ku Lixia , Su Huihui , Chong Leelyn , Chen Yanhui
Published: January 2024

Drought is a major abiotic stress that limits maize production worldwide. Therefore, it is of great importance to improve drought tolerance in crop plants for sustainable agriculture. In this study, we examined the roles of Cys2/His2 zinc‐finger‐proteins (C2H2‐ZFPs) in maize's drought tolerance as C2H2‐ZFPs have been implicated for plant stress tolerance. By subjecting 150 Ac/Ds mutant lines to drought stress, we successfully identified a Ds‐insertion mutant, zmc2h2‐149, which shows increased tolerance to drought stress. Overexpression of ZmC2H2‐149 in maize led to a decrease in both drought tolerance and crop yield. DAP‐Seq, RNA‐Seq, Y1H and LUC assays additionally showed that ZmC2H2‐149 directly suppresses the expression of a positive drought tolerance regulator, ZmHSD1 (hydroxysteroid dehydrogenase 1). Consistently, the zmhsd1 mutants exhibited decreased drought tolerance and grain yield under water deficit conditions compared to their respective wild‐type plants. Our findings thus demonstrated that ZmC2H2‐149 can regulate ZmHSD1 for drought stress tolerance in maize, offering valuable theoretical and genetic resources for maize breeding programmes that aim for improving drought tolerance.
The degree of hydraulic vulnerability segmentation at the individual level is related to stomata sensitivity in seedlings of three oak species
Authors: Li Yining , Fan Dayong , Huo Chenrui , Wang Jiaxi , Wang Xu , Dong Zexia , Meng Xiaoqian , Li Guolei
Published: January 2024

It is hypothesized that ‘hydraulic vulnerability segmentation’ (the vulnerability of expendable organs is higher compared to the vulnerability of nonexpendable organs) can enhance the drought‐tolerance of trees. However, prediction of positive segmentation (leaf minus branch) did not gain undisputed support in field observations. Further, the main organs of trees (leaf/trunk/root) are vital to test the hypothesis at the individual level. Unfortunately, most verifications of the hypothesis focus on the hydraulic vulnerabilities between leaves and terminal branches of mature trees. In this study, we grew three deciduous oak (Quercus mongolica, Q. variabilis and Q. aliena) seedlings (6 months old), and measured the hydraulic vulnerabilities of leaves (by rehydration method), main stems and main roots (by bench dehydration method). The sensitivity of stomata to water potential was obtained by monitoring the stomata conductance response to drought stress. The xylem anatomy of main stem and main root was also measured. It was found that the leaves of all three oak species exhibited greater vulnerability than the main stems and main roots. The leaf‐stem segmentation was more pronounced than the stem‐root one, and the stem‐root in Q. aliena even showed a reversed segmentation. Further, we found that higher stomatal sensitivity was associated with higher P50,leaf (water potential at 50% loss of leaf hydraulic conductivity), and narrower segmentation between leaf and the most embolism‐resistant organ. Collectively, our results support the ‘hydraulic vulnerability segmentation’ hypothesis at the individual level, and highlight the importance of stomatal regulation in hydraulic vulnerability segmentation.
Responding to feedback about implicit bias
Authors: Howell Jennifer L. , Lofaro Nicole , Ratliff Kate A.
Published: January 2024

Providing people with feedback about their intergroup biases is a central part of many diversity training and other bias‐education efforts. Although this practice may increase self‐awareness, people sometimes respond negatively to learning about their own biases. In the present review, we provide a framework for understanding when feedback about intergroup bias should lead to behavior change intentions, and when it can work against that goal. Specifically, we suggest that feedback about performance on measures of bias (e.g., the Implicit Association Test) will cause psychological discomfort to the extent that feedback about intergroup bias is: (1) discrepant from self‐reported attitudes, and (2) more personally or socially unacceptable than self‐reported attitudes. We then suggest two possible routes stemming from that psychological discomfort: If people accept personal responsibility for feedback, they will respond to psychological discomfort with compunction and direct efforts toward behavior and attitude change. By contrast, if people reject personal responsibility for feedback, they will respond defensively, derogating the feedback and trying to prove that the results are inaccurate. We use responses to feedback about implicit bias as a test case to demonstrate our model and discuss the current state of the literature on responding to IAT feedback. We also discuss interventions that can move people from defensiveness to compunction and open our metaphorical “file drawer” to discuss lessons learned.
Conceptualizing psychological well‐being as a dynamic process: Implications for research on mobile health interventions
Authors: Heshmati Saida , Muth Chelsea , Roeser Robert W. , Smyth Joshua , Jamalabadi Hamidreza , Oravecz Zita
Published: January 2024

We introduce a theoretical framework for conceptualizing Psychological Well‐Being (PWB) as a process that unfolds over short and longer time‐scales. We argue that this framework can be especially useful for studying the change mechanisms in PWB within the context of mobile Health (mHealth) interventions. Four lines of research are considered within this framework to inform the scientific exploration of PWB in the context of mHealth interventions. First, we explore key dynamic characteristics of change in PWB functioning. Second, we discuss PWB intervention response as a learning process (i.e., meaningful and transformational changes in state), reflected as change in key dynamic characteristics of PWB. Third, we explain mechanisms of change in PWB intervention practices through an underlying process of skill development. Fourth, we discuss intervention response heterogeneity within this framework. The approach we outline is intended to articulate currently unanswered, process‐oriented research questions about PWB interventions, how they work, and a methodological path forward for exploring them.
Analytical Theory of Aeroplanes in Rectilinear Flight and Calculation of the Maximum Cruising Radius
Authors: Rateau A.
Published: January 2024

Theory of Horizontal Rectilinear Flight of Aeroplanes. Description of underlying basic principles, together with their application to the solution of certain important problems.

Characteristic Relations Connecting the Main Factors Governing the Operation of the Propellers. In these the author expresses practically all functions in terms of slip or functions thereof.

Characteristic Functions and Coefficients of an Aeroplane. These are expressed in terms of weight of the aeroplane, incidence and four specific coefficients which have to be determined by measurement and computation.

Minimum Consumption of Fuel and Oil per Kilometer of Flight. The determinations of consumption which are made are dependent on the altitude of flight; tables are given showing the results of computations for what the author calls the “Aeroplane-Type.”

Cruising Radius of Aeroplanes. Formulœ are given for determining the cruising radius and it is shown that with the present state of aeronautical engineering the cruising radius in still air is theoretically limited to 7000 km. (4350 miles) and that even this can be achieved only by flight at elevations ranging from 16,000 to 25,000 ft.
Aluminum Castings
Authors: Jeffries Zay
Published: January 2024

In this paper the author first gives particulars of the various aluminum alloys used for casting purposes. He then deals with the metallography and physical properties of these alloys, following which are notes on maximum and minimum weights, tolerances on dimensions and machining data. Later sections deal respectively with heat treatment, aging, effect of thickness of section and rate of chill on physical properties of aluminum alloys, fatigue resistance, special places where the use of aluminum castings is indicated by reason of their lightness and ease of machining, and with the selection of alloys for special purposes.
The Dissipation of Heat by Various Surfaces
Authors: Taylor T. S.
Published: January 2024

This paper is a discussion of the value of sheet asbestos as a covering for hot-air pipes. The author as a result of many experiments found that tin covered with 0.33-mm. (0.013 in.) sheet asbestos will dissipate about 37 per cent more heat than a bare tin pipe; asbestos-covered tin having a layer of dust, 32 per cent more, and tin with a layer of dust only, 7 per cent more. Calculations based on a series of tests indicate that it would require a covering of about 0.2 in. of sheet asbestos to make the loss from the covered pipe equal to that from the bright uncovered pipe. A thickness of 0.4 in. of asbestos, however, would result in a saving of 25 per cent over that of bare pipe, and about seven layers of 0.013-in. sheet asbestos loosely applied on a bare pipe would effect a saving of about 25 per cent. Application of three layers of air cell 0.25 in. asbestos paper will net a saving of 25 per cent over that of a bare pipe.

The author also presents figures, derived from tests, showing the effect of air velocity upon the dissipation of heat. Curves are given showing the watts dissipated per unit area and air velocity for definite surface temperature excesses of from 10 to 70 deg. The effect of the angle of incidence of the air is also discussed in the light of experimental work and it is shown that the maximum dissipation of heat takes place when air is blown over the object at an angle of from 40 to 45 degrees.
The Separation of Dissolved Gases From Water
Authors: McDermet J. R.
Published: January 2024

This paper covers the results of a research on the separation of dissolved gases from boiler feedwater, both on a laboratory and a commercial-plant scale. Fundamentally the process consists of the rapid injection of heated water into a region of vacuo, and an explosive boiling of it at the expense of the heat of the liquid available to the vacuum, with a simultaneous recovery of the heat liberated to the vacuum by a heat exchanger or condenser cooled by the incoming water, preliminary to its heating. It is possible to deduce from a résumé of existing knowledge the results to be expected in the elimination of corrosion from boilers and economizers fed with oxygen-free water. Chemical analyses suggest the elimination of carbonates dissolved in water as bicarbonates in excess of their true solubility as carbonates. Test data are submitted to show the economies to be gained from the surface condensation of steam free from non-condensible gases both in increased conductivities and higher vacua.
The First Transcontinental Motor Convoy
Authors: Jackson E. R.
Published: January 2024

The Transcontinental Motor Convoy of 81 vehicles and trailers which started from Camp Meigs, Washington, D. C., at 8 a.m., on July 7, 1919, and finished at San Francisco, Cal., on September 6, 1919, was the first attempt to push through a large train of heavily loaded trucks from one end of the country to the other. Back of it were placed the resources of the War Department, and some measure of its success was due to the friendly coöperation of the local bodies of the communities through which the Convoy passed.”
The German Defenses of the Coast of Belgium
Authors: Miller H. W.
Published: January 2024

On October 15, 1914, the Germans occupied Ostend and all of the Belgian Coast north of that point. During the next few days their offensive gained for them the coast for a distance of about 10 miles farther south, including the city of Nieuport. They were unable to hold all of their gains against the offensives of the Belgians and British during the next few months, and their line was pushed back to a point between Nieuport and Ostend, at Westende, about 8 miles south of Ostend. This line became a part of what has been known familiarly as the Hindenburg Line. This line was heavily fortified by the Germans, and their men were provided with adequate shelters. Four years after the original occupation, almost to a day, the Germans were driven out of Ostend, on October 17, and from Zeebrugge farther north, on the 18th.”
Effect of Load Factor on Steam–Station Costs
Authors: Junkersfeld Peter
Published: January 2024

The following paper discusses the factors affecting steam-station costs, particularly the load factor. Financial loss, the author states, will result whenever it becomes necessary to operate a power station at a substantially higher or at a substantially lower annual load factor than that for which the station was properly designed. The load factor should be carefully considered in locating a central station as well as in the selection of equipment. Fuel, usually an item of great expense, is dependent upon the load factor, the efficiency in the use of fuel being greater at the higher load factors. Curves are given to show relative generating costs and boiler rating as affected by load factor, typical week-day load curves and load factors, and the load factor as it occurs from day to day and month to month.
The Interpretation of Boiler-Water Analyses
Authors: McDermet J. R.
Published: January 2024

The importance of taking into consideration the corrosive properties of a boiler feedwater as well as its tendency to form scale is coming to be more and more generally recognized, and the interpretation of the various types of analyses employed for the purpose forms the substance of the present paper.

Feedwater impurities fall into at least one of three groupings: dissolved solids, pollution products, and dissolved gases. The dissolved solids determinable under a technical analysis naturally group themselves into corrosive and scale-forming constituents according as they are or are not highly ionized in aqueous solutions. Pollution products are detected by inferential methods in a partial sanitary analysis, but the effects of various types of pollution other than manufacturing wastes as indicated by the analysis are concretely set forth. Dissolved-gas analyses, meaning in the main dissolved-oxygen analyses, are discussed in relation to the safe operating limits of hot-water feed lines, boilers, and cast-iron and steel-tube economizers.

An appendix translates the facts of the paper into a working plan for use in the chemical laboratory.
Advantages of Large Freight Locomotives, Particularly the 2-10-2 Type
Authors: Stuebing Albert F.
Published: January 2024

In this paper the author points out the more important considerations involved in a study of the economic value of various types of motive power and demonstrates the complexity of the problem. Probably, he holds, no absolutely correct analysis is possible, and surely not practicable. The choice of motive power is of extreme importance because the characteristics of the power affect the earnings more than any other single factor and determine the efficiency of operation usually throughout the life of the engine. For this reason the choice of the locomotive should be made with extreme care. The final decision should be based on a definite knowledge of the economies that can be realized, not on unsupported opinion. Engineering methods are essential in working out the solution, and the study of the problem offers a field for constructive coöperative work by the members of the engineering societies.
Compounding the Combustion Engine
Authors: Sperry Elmer A.
Published: January 2024

To engineers versed in the problems of selecting and designing prime movers, the advantages of the compound combustion engine are readily apparent. It is light compared with the normal Diesel, being in special cases less than one-tenth, and in some instances less than one-twentieth, the weight for the same output. Its mechanical efficiency is extremely high, and a distinct gain in overall efficiency from fuel to shaft has been made, as well as a very definite gain in simplicity, direct performance and smoothness of the crankshaft diagram. This has been achieved while adhering to the best practice, namely, four-cycle operation.

This paper presents the results of research by the author extending over a series of years, during which not only has the high-pressure principle been thoroughly established, but all the important requirements have been worked out, and finally an engine embodying practically all the advantages has been subjected to long continuous runs.

It is the author’s belief that the results here announced for the first time warrant the prediction that engines employing the multi-stage or compound principle will at no distant date occupy a dignified place in the combustion-engine art. If this principle should assume leadership, it will of course only be because of its demonstrated practical usefulness and general merit. At present these appear to be of such magnitude as to at least insure wide adoption.
Commercial Operation of Airplanes
Authors: Lent L. B.
Published: January 2024

In order that those interested in the operation of airplanes for commercial use may have an idea of what may be expected of a properly organized and operated service, the author presents in this paper an analysis of the record of the Air Mail Service of the United States Post Office Department for the period October 1, 1920–September 15, 1921. The operating record, the cost of operation, and the life and maintenance of planes and of engines give a basis upon which the author points out possible improvements, the most important in present practice being the use of efficient commercial planes equipped with a thoroughly reliable power plant. In regard to cost of operation the author states that the total operating cost should not exceed seventy cents per plane-mile for single-engine planes of not over 400 hp.
A Study of the Elastic Properties of Small-Size Wire Cable
Authors: Moore R. R.
Published: January 2024

In aircraft work use is made of several varieties of small-diameter steel cable knowledge of the physical characteristics of which is important for efficient design. The present paper gives results of a series of tests carried out at McCook Field, Dayton, Ohio, in which it is shown that the modulus of elasticity of small-sized wire aircraft cable varies from 15,000,000 to 28,000,000, depending upon the size and type of the cable. The maximum difference between moduli of specimens of the same size and type of cable may be as high as 3,000,000.

It was also found that the modulus of elasticity may be raised by loading the cable below the elastic limit, and that resting the cable does not seem to have any definite effect on the modulus. The elastic limit may be raised by loading the cable a little beyond this point, the maximum increase obtained amounting to 63 per cent of the original elastic limit.
Testing Emergency Fleet Boilers Using Oil Fuel
Authors: Dean F. W.
Published: January 2024

Tests upon the standard four-pass water-tube marine boiler designed by the United States Shipping Board Emergency Fleet Corporation, using coal as fuel, were reported by the present author and Mr. H. Kreisinger in a paper read at the Annual Meeting of the Society in 1919. In consequence of the introduction of oil for fuel on many of the steamships of the United States Shipping Board, it became desirable to ascertain the relative merits on several of the available mechanical atomizing oil burners for boilers. Tests were accordingly run, the boiler used having a heating surface of 2518 sq. ft., a furnace volume of 408 cu. ft., and a commercial horsepower of 435 on the basis of the marine rating of 6 lb. of water to a square foot of heating surface per hour. These tests and the results obtained form the subject of the present paper.
Boiler-Plant Efficiency
Authors: Azbe Victor J.
Published: January 2024

The usual wastes in boiler plants are brought out strikingly by the author by means of tables and curves of boiler performance compiled from a large number of observations.

The object of this paper is to show to what extent these wastes are preventable or can be made to balance each other, and to recommend a standard for boiler operation toward which designers and operators of boilers may aim.

The author considers that there still remains an immense field for experimental research to obtain the necessary data for boiler construction. The requirements of the ideal boiler installation of today are summarized.
Fuel Saving in Modern Gas Producers and Industrial Furnaces
Authors: Chapman W. B.
Published: January 2024

This paper calls attention to the wastes of fuel in the industries using gas producers and producer-gas furnaces. Both of these problems are in the field of combustion engineering.

The progress made in the last twenty-five years in gas-producer construction is emphasized by the descriptions of leading mechanical producers now in the market, together with an indication of their fuel-saving possibilities.

Attention is called to the savings made possible by using suitable accessories in the gas house.

To illustrate the possible savings in furnace operation a description is given of a distinctive type of recuperative furnace. The extension of the use of such a furnace to pulverized coal and oil would, the author states, result in similar savings.
Avoidable Waste in Locomotives as Affected by Their Design
Authors: Partington James
Published: January 2024

The best way to overcome waste in locomotive operation is to design the locomotive in the first place so that it will fulfill the efficiency requirements of

1 A drawbar horsepower for the minimum amount of fuel

2 A drawbar horsepower for the minimum amount of weight of locomotive and tender

3 A drawbar horsepower for the minimum cost of repairs.

Fuel economy is effected by firebrick arches, superheaters, feedwater heaters, generous steam spaces, automatic stokers, etc. Minimum weight is secured by careful design of the machinery parts, use of special materials, use of the independent booster for special grades. Minimum cost of repairs is dependent on the use of as few bolted parts as possible, accessibility of parts, removability, and interchangeability. Standard replacement parts can be secured from builders.

Much waste in locomotive operation can be avoided by making a careful study of present motive-power equipment, modernizing it where necessary, or replacing by new equipment. Several examples of what has been accomplished in service by locomotives designed to yield maximum efficiency are given.
The Strength of Airplane Rib Forms
Authors: Brown D. T. , Diefenbach R. J.
Published: January 2024

As illustrating the problem of the strength of materials entering into airplane construction and the degree of research necessary for their proper solution, the following report of an investigation carried out at the United States Forest Products Laboratory will be of interest. In the design of airplane ribs the prime requisite is to obtain the maximum strength with minimum weight of rib. Two factors enter into the problem: the form or design of the rib and the method of its construction in relation to the grain of the material. It will be seen that the investigation reported was conducted in a very complete manner and that conclusions of great value in the design of this essential part of the airplane are brought out.
Material-Handling Equipment as Used in the Iron and Steel Industry
Authors: Leach F. L.
Published: January 2024

This paper describes the handling machinery and apparatus used in the manufacture of steel. From the time that the ore leaves the mines until the steel goes through the last process at the mill it is moved about exclusively by different types of heavy machinery designed especially for the purpose. The author expresses the hope that through his description, weak points in present-day practice will show themselves and means of improvement be suggested.
Reduction of Fuel Wastes in the Steel Industry
Authors: Cutler F. G.
Published: January 2024

The paper sets forth the economy of utilizing blast-furnace gas, at one time considered to be of little material value, in reducing the wastes of the steel industry. It is shown how the quantity of gas to be expected in the production of one ton of pig iron may be computed, and the uses to which this gas may be put are analyzed quantitatively. A heat balance, based on the production of one ton of pig iron, is presented, showing the sources of heat and the requirements for blast-furnace and steel-mill operation. It shows that the total heat from the by-products of a ton of pig iron is more than sufficient to finish a ton of steel. The heating requirements are not met by the tar and by-product gas, although the average power requirements are more than met by the blast-furnace gas and coke breeze. It therefore becomes desirable to reduce the heating requirements for the production of steel by using more efficient heating furnaces, and to conserve all possible heat by charging hot steel into the soaking pit and reheating furnaces, in order to reduce the quantity of fuel required for supplementary heating.
The Control of Boiler Operation: Simplified Formulas for Calculating Chimney, Combustion and Absorption Losses — A Proposed Fuel Unit for Bituminous Coal, Etc.
Authors: Uehling E. A.
Published: January 2024

The problem the author sets for himself is to suggest a method that will bring complete and intelligent control of boiler operation, so far as combustion and absorption efficiency are concerned, within the horizon of comprehension and easy execution of the average operating engineer, enabling him to determine heat losses and to separate them into their several components so that he can know just where and to what extent losses occur and that he may be better able to minimize them by intelligent application of the proper remedy. The author proposes the pound-carbon fuel unit, which he shows to be practically equicalorific, and which equals 14,450 plus 62,000 times the percentage of available hydrogen.

Formulas are presented for calculating heat losses up the chimney and the combustion and absorption losses are analyzed. The application of the formulas to some scientifically conducted tests is shown.
The Size of Dry-Vacuum Pump to Employ in a Given Case: A Rapid and Practically Accurate Method for Its Determination, Applying to Any Set of Conditions
Authors: Noyes Edward W. , Sturtevant Harold V.
Published: January 2024

In pumping from atmospheric pressure down to a given vacuum with a dry-vacuum pump, as during the process of exhausting a closed tank, the volumetric efficiency of the pump varies from that at atmospheric pressure to that corresponding to the given vacuum and an average value has to be determined to use in the theoretical formulas which apply to this kind of service.

Two methods of determining the average volumetric efficiency were successively tried out by the authors and the results plotted in the form of curves, but these results did not check satisfactorily with those obtained in actual tests of an installation. The process of calculation employed in the second (and somewhat more accurate) method was then reversed, and, working with actual test data, values were obtained from which a “constant” curve was plotted, this curve giving closely accurate results from 80 per cent perfect vacuum up. With the aid of this “constant” curve two charts have been plotted, by means of which it is possible to determine rapidly and with sufficient accuracy (1) the size of pump required to exhaust a given volume to a specified degree of vacuum in a predetermined time; or (2) where a vacuum pump is already installed, the time required to exhaust a given volume to a specified degree of vacuum.
Stress Distribution in Electric-Railway Motor Pinions as Determined by the Photo-Elastic Method
Authors: Heymans Paul , Kimball A. L.
Published: January 2024

This paper embodies some results of a general scientific study undertaken by the General Electric Company for the development of superior electric-railway motor pinions. The particular portion of the work described was performed at the Massachusetts Institute of Technology, using the General Electric Company’s apparatus for stress determination in transparent models by the photo-elastic method. Some of the supplementary mechanical tests were made at Schenectady, and throughout the work close contact was maintained with the Railway Motor Department and the Research Laboratory at Schenectady. A brief description and discussion of the photo-elastic method is given in the first part. The stress distribution in, and the causes of ruptures of, given types of gear pinions used in electric-railway motors, as investigated by the photo-elastic method, are afterward reported upon and discussed.
The Elasticity of Pipe Bends
Authors: Crocker Sabin , Sanford Sterling S.
Published: January 2024

In this paper the authors develop in detail mathematical formulas connecting the deflection of different types of pipe bends with the force producing deflection, and also expressing the stress set up as a function of the observed deflection and the constants of the bend. They describe experiments made to check force vs. displacement, and present charts for use in selecting the proper size and shape of bends to take care of a given expansion, and to determine the force exerted by a bend when in a given state of deflection. In general they recommend bends of larger dimensions than are ordinarily used, and their figures are said to lie on the side of safety. In some cases the bends tested showed a greater flexibility than anticipated, due to minute folds formed on the compression side when bending pipe to short radius.
Torsion of Crankshafts
Authors: Timoshenko S.
Published: January 2024

In order to apply the dynamics of elastic systems to the designs of engines it is necessary to determine the torsional properties of the crankshaft. In the present paper the author considers the case of a crankshaft with a single throw and establishes the mathematical relations for such a case. He investigates three conditions of such a crankshaft: (a) no constraint, corresponding to ample clearance in the bearings; (b) complete constraint, corresponding to no clearance in the bearings; and (c) partial constraint, corresponding to ample clearance in the halves of the bearings nearest the web and no clearance in the other halves.
The Design of Cooling Towers
Authors: Robinson C. S.
Published: January 2024

The author points out that engineers have designed cooling towers in the past on empirical information and in accordance with the experience of previous successful designs. Wide departure from standard designs is difficult because of the lack of scientific basis for the design. The author therefore establishes the general principle applicable to cooling-tower design and derives equations for the use of the designer. He presents a quantity of experimental data to substantiate the validity of his formulas and shows by an actual experiment how these formulas are applicable to the design of a counter-current cooling tower.
Ash Handling
Authors: Hunter John , Cotton Alfred
Published: January 2024

Various methods of handling ash are described and illustrated, beginning with early developments on shipboard. The greater part of the paper, however, deals with stationary practice, beginning with rudimentary and progressing to the most modern installations, of which schematic and actual examples are given.

Methods of removing ashes from basement boiler rooms are followed by a discussion of the design, construction, and capacity of hopper ashpits, including their doors and water seals. Systems of mechanical conveyance and elevation are described, comprising ash cars, skip hoists and bucket conveyors. Fluid conveyance, as represented by water sluicing and steam-jet conveyors, is discussed in general, and typical examples of both are illustrated and described in detail. Particulars of ash bunkers and settling basins are followed by a discussion of the final disposal of ash.
Refinery and Rolling Mill for Monel Metal, Huntington, W. Va.
Authors: Wotherspoon W. L.
Published: January 2024

This paper describes in detail the steps taken in selecting the site for the location of a mill for rolling monel metal. The economic problems involved are stated and the facts leading to their solution are given. The remainder of the paper deals with the layout of the plant, emphasizing some features of design that are of particular interest.
Tests of a Type W Stirling Boiler at the Connors Creek Power House of the Detroit Edison Company
Authors: Thompson Paul W.
Published: January 2024

This paper deals with extensive tests conducted during 1921 on a large Type “W” Stirling boiler at the Connors Creek power house of The Detroit Edison Company. Four different arrangements of the boiler baffling were employed and the results obtained with each are shown. Separate tests were made using four different grades of coal in order to determine which was most suitable. Several operating tests were made to obtain data on different methods of banking, the effect on the temperature of flue gas of varying the time interval between the blowing of flues, and different methods of operating boilers during the low-load period at night.

From the results of the tests with different baffle arrangements, seventeen of these large boilers have been rebaffled with a resulting improvement in boiler-plant efficiency and an increase in the degree of superheat of the steam. Additional improvement is expected as more boilers are rebaffled. From the data and results of these tests, the Babcock & Wilcox Company, working in conjunction with The Detroit Edison Company, have developed a new design of this type of boiler. Four boilers of the new design have been installed in the Marysville power house of The Detroit Edison Company, but economy results on the installation are not yet available.
Feed Heating for High Thermal Efficiency: Economies of 25,000-kw. Power Stations Using Single- and Multiple-Stage Condenser Heaters, With and Without Economizers, Determined to Demonstrate the Effect of Varying the Feedwater Temperature
Authors: Helander Linn
Published: January 2024

The author investigates the problem of determining the correct feedwater temperatures for conditions of high thermal efficiency. He applies his methods to a 25,000-kw. power station, investigating the conditions when using single- and multiple-stage condenser heaters, both with and without economizers. In appendices are given all the necessary data for the solution of the problems and the formulas by which the results are obtained.

The paper is illustrated with curves obtained from the solution of the problem, various conditions being considered and the results compared. The paper considers the problem from the viewpoint of thermal efficiency only and does not include other factors such as investment, operating cost, etc.
Lumber Dry Kilns
Authors: Perry Thomas D.
Published: January 2024

The three main divisions into which lumber dry kilns may be grouped are blower, condenser, and ventilated kilns. The author, who believes that scientific kiln drying offers engineers a splendid field for research work, describes these types and discusses the possibilities of each, with particular reference to the ventilated kiln, of which there are several classes. The questions of moisture deficit and equilibrium, air interchanges, and drying cycles are adequately treated, and data showing the relation between relative and absolute humidity during the drying period are included.
The Oil Venturi Meter
Authors: Smith Ed S.
Published: January 2024

The paper presents a method of applying the venturi meter to the measurement of the flow of oil and other viscous fluids. It gives a chart showing value of the venturi-meter coefficient “C” over a range of turbulence from 0.0003 to 200,000, and flow graphs for a typical meter, by means of which the quantity flowing may be determined when a few easily measured constants are known.
The Cross–Flow Impulse Turbine
Authors: Nagler Forrest
Published: January 2024

The author reviews the history of the development of the hydraulic turbine and shows that there is a gap between the field of the reaction turbine and the impulse wheel. This is due to the fact that the impulse wheel, as now built, has the slowest speed of all turbines, and that its highest specific speed is much below that of the reaction turbine. The cross-flow turbine, the principles of which are developed in this paper, will fill this field. The paper is not the presentation of a finished design, but rather the outline of the path that must be followed to meet new conditions in hydraulic power development.
Effect of Variations in Design of Milling Cutters on Power Requirements and Capacity
Authors: Graves Benjamin P. , Hall James A.
Published: January 2024

A series of tests to determine the effect of changes in the number of teeth, spiral angle, rake angle, and cutting speed of the cutter on the power consumption, tendency to chatter, and stresses set up in the machine, led to the following conclusions:

Coarse-tooth milling cutters require less power to remove a given amount of metal per minute than fine-tooth cutters

When compared on a chip-per-tooth basis, the finish given by a coarse-tooth cutter is better than by the fine-tooth cutter

Low-cutting-speed operation of fine-tooth cutters to give a large feed per tooth increases the stresses in machine and fixtures.

Fine-tooth cutters are inferior to coarse-tooth cutters when the relative tendency to chatter is considered.

Moderate rake angles reduce the power consumption and are desirable on all cutters to be used on mild steel. Large rake angles increase the tendency to chatter.

The spiral angle has little effect on power consumption; a considerable spiral angle is desirable, however, as fewer teeth may be used, smoother action is obtained, and the tendency to chatter is reduced.

With certain exceptions noted in the paper, coarse-tooth cutters of the type now generally manufactured are superior to fine-tooth cutters for all classes of production work.
The Efficiency of the Scotch Marine Boiler
Authors: Jefferson C. J.
Published: January 2024

The average merchant cargo steamer develops boiler efficiencies of but 55 to 60 per cent with coal-fired boilers, and 60 to 65 per cent with oil-fired boilers. That these efficiencies are much below those possible is shown by the series of tests given in this paper, in which efficiencies as high as 76.7 per cent with coal and 82.8 per cent with oil were developed. Considerable fuel savings are possible in marine practice by means of proper supervision of the operating force.
The Integrating Gate: A Device for Gaging in Open Channels
Authors: Doolittle H. E.
Published: January 2024

The integrating gate is a device for measuring the flow of liquids in open channels which, it is claimed, avoids some of the disadvantages of present methods, such as the weir, the rating flume, the venturi flame, etc. It consists of a freely swinging gate suspended in the channel and practically closing it. The flow of liquid causes this gate to assume an angle from the vertical, which angle is an index of the flow. Sufficient experimentation has been done to show that the error and individuality of different gates is small enough for practical purposes. The rating curve can be predetermined, and the loss of head through the gate is considerably less than in the weir or venturi flume.
The Solid–Injection Oil Engine
Authors: Shepherd H. F.
Published: January 2024

The development of the solid-injection oil engine during the past three years has engaged the attention of many designers. Unfortunately, most of the information gained by experiments has been withheld from publication and the net result has been a duplication of laboratory and test-floor effort. The author has undertaken to present the most pertinent facts on the development of the engine from the former hot-surface unit and points out the influence of combustion-chamber design, spray angle and velocity, atomization, detonation, and other problems confronting the oil-engine designer.
High Pressure, Reheating, and Regenerating for Steam Power Plants
Authors: Hirshfeld C. F. , Ellenwood F. O.
Published: January 2024

In this paper the authors discuss the relative thermal and investment costs involved in modern turbo-generator stations, using various steam pressures and temperatures, and six different cycles. Particulars regarding the study are summarized in the three paragraphs immediately following.
Economy Characteristics of Stage Feedwater Heating by Extraction: Practical Computation and Maximum Realization of Extraction Gains for Power Plants of Present Trend in Design
Authors: Brown E. H. , Drewry M. K.
Published: January 2024

Feedwater heating by extraction from the main unit, becoming increasingly important with rising steam pressures, complicates the computation of heat balance. The authors point out the influence of each possible factor in the computations, present a practical method for computing extraction cycles, and deal with various factors affecting turbine-room economy, these being more particularly enumerated in the first three paragraphs of the paper.
Analysis of a Machine-Shop Problem on a Quantity and Final-Economy Basis
Authors: De Leeuw A. L.
Published: January 2024

This paper discusses the nature, of the analysis which should be followed in determining the most economical method of machining work, either in large or small quantities. It leaves out of consideration all items excepting those relating to the actual machining processes. Particular attention is called to the difference between the saving of labor cost and the ultimate economy. As an example some of the operations on an automobile connecting rod are taken.