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The purpose of this paper is to reveal the characteristics of hydrodynamic load capacity and torque transferred by oil film with variable viscosity, and the effect of groove number, width and depth on the hydrodynamic load capacity and torque transfer.

The radial temperature of friction pair and viscosity of YLA‐N32 hydraulic oil were measured through experiments, and a viscosity‐diameter expression was deduced using polynomial fitting method. Analytical expressions for hydrodynamic load capacity and torque of the oil film were deduced based on hydrodynamic lubrication theory.

The investigation shows the hydrodynamic load capacity and transferred torque with variable viscosity are much less than that with constant viscosity. Load capacity increases with the increase of groove depth which is the most significant influence factor, while it has the least influence on torque. Groove width has great influence on load capacity and torque. The load capacity increases with the increase of groove width; contrarily, torque decreases with the increase of groove width. Groove number has little influence on load capacity, while it has great influence on torque. The torque decreases with the increase of groove number.

In this paper, analytical solutions for hydrodynamic load capacity and torque of the oil film with variable viscosity are deduced. The paper reveals the relationship between hydrodynamic load capacity, torque transfer and groove number, width and depth.

Current issues of Publishers' Weekly are reporting serious shortages of paper, binders board, cloth, and other essential book manufacturing materials. Let us assure you these shortages are very real and quite severe.

The matter of predicting disasters has always been one of the hottest and most challenging tasks in geology. Earthquakes are among the most destructive ones among all the natural hazards. Occurring often without any warning, they are the most feared and unpredictable natural phenomena. In recent years with the emergence of new remote sensing instruments and techniques, geologists interested themselves to define accurate and reliable procedures to foresee disasters using this new technology. This paper aims to examine some of the data that have been used so far in earthquake prediction as well as cheap, relevant remotely sensing and geographic information systems methods to acquire and manipulate data.

Earthquakes are not the same in terms of origins, places (depth) and effects. So after having a brief look at the earthquakes, this paper examines the data that can be used for predicting earthquakes and reviews some of the remote sensing methods used to predict tectonic earthquakes. According to the types of measurements, remote sensing methods can be categorized in three main types; crust displacement, thermal and electromagnetic detecting techniques. Regarding the area's geological characteristics, satellites with optical and/or synthetic aperture radar sensors applications in prediction of large‐scale natural disasters will be discussed.

Presentation of the definitions and characteristics of earthquakes, categorized representation of the types of data used in this field as well as the types and names of the ground, aerial‐ and space‐borne data providers are the most important products of this review paper.

This method, if fully and systematically conducted, can be the cornerstone of an earth‐predicting system.

This paper addresses revolutionary changes in the education, fertility and market work of U.S. families formed in the 1870s–1920s: Fertility fell from 5.3 to 2.6; the graduation rate of their children increased from 7% to 50%; and the fraction of adulthood wives devoted to market-oriented work increased from 7% to 23% (by one measure).

These trends are addressed within a unified framework to examine the ability of several proposed mechanisms to quantitatively replicate these changes. Based on careful calibration, the choices of successive generations of representative husband-and-wife households over the quantity and quality of their children, household production, and the extent of mother’s involvement in market-oriented production are simulated.

Rising wages, declining mortality, a declining gender wage gap, and increased efficiency and public provision of schooling cannot, individually or in combination, reduce fertility or increase stocks of human capital to levels seen in the data. The best fit of the model to the data also involves: (1) a decreased tendency among parents to view potential earnings of children as the property of parents and (2) rising consumption shares per dependent child.

Greater attention should be given the determinants of parental control of the work and earnings of children for this period.

One contribution is the gathering of information and strategies necessary to establish an initial baseline, and the time paths for parameters and targets for this period beset with data limitations. A second contribution is identifying the contributions of various mechanisms toward reaching those calibration targets.

At the turn of the twentieth century, various Socialist parties vied for a place in the American political system, making alliances where possible and convenient with elements of organized labor. Robert Franklin Hoxie, an economist at the University of Chicago whose principle contributions lay in his writings on the labor movement, wrote a series of essays in which he scrutinized the activities of the Socialist Party of America as it appeared to be at the time poised to become a viable force in American politics. This essay examines Hoxie’s writings on the conventions of the Socialist Party within the context of the political dynamic of the period and reveals his interpretations of events based on contemporary accounts and first-hand observations.

After establishing the terminology, shows how the choice of the name of the subject of a document and the rendering of the name in the heading of the specific subject entry can be got by facet analysis based on postulates and principles. After showing that subject headings constitute an artificial language, points out that using facet analysis for subject heading does not amount to using class number. Marks out the area for an objective statistical survey of sought heading for subject entry. Calls on Council for Library Resources Incorporated to provide for this project.

The purpose of this paper is to develop novel ashless additives and to meet the need for formulating ashless anti‐wear (AW) hydraulic fluid or other industrial lubricating oils. This paper also aims to investigate the tribological behaviours and mechanism of an acrylate of dialkyl dithiophosphoric acid (ADDP), as an additive in some group I/II base oils compared with some traditional s‐p containing AW additives.

ADDP is synthesized in the laboratory. The chemical composition and structure of the lubricating additive are analyzed by means of infrared spectroscopy. Its extreme pressure (EP), AW and friction reduction properties as additive in base oils, compared with some traditional s‐p containing AW additives, are investigated using a four‐ball machine according to relative testing standards. The tribological mechanism is discussed according to the scanning electron microscope (SEM) analytical data.

The results indicate that the four‐ball PB value of the prepared ADDP in HVIWH650 is better than that of the IRGLUBE 353; the thermal stability of ADDP is equivalent to the zinc dialkyl dithiophosphate (ZDDP) and the SEM data show that the prepared ADDP additive could form a layer of uniform film on the worn surface serving as lubricant and protective film. This may be the chief reason why the prepared ADDP possesses better AW property than ZDDP.

However, more experimental studies such as the synergic effect with other additives should be performed, from which it could be learned whether the novel AW additive would be applicable in industrial oils.

The results may be useful for the researchers to formulate some ashless industrial oils.

A novel additive was synthesized in the laboratory; it would find a promising industrial application as an ashless AW additive.

The purpose of this paper is to develop a new oil‐in‐water (O/W) emulsion used for alpha phase brass, which can increase the antiwear and anti‐galling abilities of the rollers, and improve the surface quality of the rolled brass sheet. The aim is to evaluate the tribological performance of new kind of O/W emulsion for the hot rolling of alpha brass, which provides the fundamental information for the selecting of new chemical group, and to understand the lubrication mechanism of the used rolling emulsion and to correlate the laboratory findings with those of industrial rolling of alpha phase brass.

According to the hydrophile‐lipophile balance theory and the evaluation results of friction, wear and lubrication using a four‐ball tribometer, a novel O/W emulsion was developed for the hot rolling process of CuZn₃₂(ASTM C26200) and CuZn₃₀(ASTM C26000) alloys by controlling the composition of the emulsion, such as emulsifying, antiwear, extreme pressure, antirust and so on. By scanning electron microscope (SEM), energy‐dispersive X‐ray (EDX), and roughness profile the tribological mechanism were studied.

The production result proved that it was easy to control the accuracy and size of the brass sheet because of the emulsion‐jet to the roller surface directly and in succession. Polyol with hydroxyl group is found to provide better lubrication and lower coefficient of friction. The actual hot rolling results proved that it was easy to control the accuracy and size of the brass sheet with the emulsion jet. The morphologies and roughness profile of the copper sheet surface were observed and measured by SEM and topographic meter under different lubricant conditions. The in situ results supported the selection of compositions of O/W emulsion. The suitable temperature of feed emulsion is over 20°C.

The tribological mechanism of friction modified emulsion is not still clear. The thermal mechanical properties of rollers under this kind of emulsion are also worth studying in the future.

Understanding the tribological behaviour of O/W emulsion, will be useful for emulsion chemists, tribologists and rolling mill users.

The current study shows new compositions of O/W emulsion used for hot rolling of alpha phase brass.

In this Festschrift, written and shared to celebrate the life and work of Dr Kathy Charmaz, I draw upon both personal reflections and Kathy's extensive writings to showcase Kathy's contributions to my personal research journey and to the field of qualitative research methodology. I examine the intersection of constructivist grounded theory and social justice research, an important theme of Kathy's work and research. I discuss three components of constructivist grounded theory that support social justice research: researcher reflexivity, prioritizing participants, and the importance of context. I share examples from my own work showing how these three facets of constructivist grounded theory contributed to an unintended yet much appreciated social justice thread in my research. My hope is through my reflection, other researchers, who were not able to meet and interact with Kathy, will be able to understand and appreciate her influence and impact, and her view of research as a responsive, flexible, and meaningful process.

This research analyzes the alignment of story framing between Samarco and news media following the dam disaster in Minas Gerais in November 2015. Drawing on framing theory as the underlying impetus, the study seeks to answer five major questions: RQ1: How did Samarco frame the mining tragedy in the aftermath of the dam collapse? RQ2: How did the news media frame the mining tragedy in the aftermath of the dam collapse? RQ3: Did the frames presented by Samarco and news media coincide? RQ4: Did the frames presented by Samarco and news media contradict? RQ5: What can be observed about the information flow and interaction between news media and the general public on social media? From a methods perspective, the study uses comparative textual analysis and NodeXL social network visualization to analyze the discourse around Samarco and information flow on social media in the aftermath of the tragedy. The results show that, while some social media content served as a forum for expressions of empathy toward survivors, social media content on Twitter mostly delivered a one-sided and positive view of the firm’s actions.