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This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement research of this kind of steel, so as to optimize the processing technology and take more appropriate measures to prevent hydrogen damage.

The hydrogen diffusion coefficient of 12Cr2Mo1R(H) steel was measured by the hydrogen permeation technique of double electrolytic cells. Moreover, the influence of hydrogen traps in the material and experimental temperature on hydrogen diffusion behavior was discussed. The first-principles calculations based on density functional theory were used to study the occupancy of H atoms in the bcc-Fe cell, the diffusion path and the interaction with vacancy defects.

The results revealed that the logarithm of the hydrogen diffusion coefficient of the material has a linear relationship with the reciprocal of temperature and the activation energy of hydrogen atom diffusion in 12Cr2Mo1R(H) steel is 23.47 kJ/mol. H atoms stably exist in the nearly octahedral interstices in the crystal cell with vacancies. In addition, the solution of Cr/Mo alloy atom does not change the lowest energy path of H atom, but increases the diffusion activation energy of hydrogen atom, thus hindering the diffusion of hydrogen atom. Cr/Mo and vacancy have a synergistic effect on inhibiting the diffusion of H atoms in α-Fe.

This article combines experiments with first-principles calculations to explore the diffusion behavior of hydrogen in 12Cr2Mo1R(H) steel from the macroscopic and microscopic perspectives, which will help to establish a calculation model with complex defects in the future.

The purpose of this chapter is to discuss how routine violence seeps into the interstices of social life. Routine violence is part of a continuum of violence that extends from intimate violence to large-scale wars. It is gendered/racialized/classed and it is often invisible because it is normalized in everyday life.

Using cases from India we illustrate facets of routine violence and then use the frame to discuss some examples from the United States.

We discuss the social implications of routine violence including the significant harm on large sections of people in today’s world.

We meld theoretical discussions about violence associated with states with scholarship on violence against women; we use Indian activists’ concepts of routine violence and examine routine violence in the United States.

The purpose of this paper is to conceive “organizing” as an indeterminate process taking place in the interstices of intra-acting elements, beyond visible/rational/intentional organizing. The term intra-activity refers to relationships between multiple elements (human and more-than-human) that are understood not to have clear or distinct boundaries. The paper aims at reframing organizing, as the effect of multiple intra-acting elements, by introducing the metaphor of shadow organizing. It offers examples as diverse as knowledge spillover, evidence-based medicine and improvisation, and the mafia’s organizational rules.

The frame of reference is metaphorical theorization, based on the metaphor of shadow organizing, and is explored through three metonymies: the forest and its sheltered spaces in penumbra; the shadow as a grey zone between canonical and non-canonical practices; and secret societies, hidden in the shadow. The shadow is the symbol of what is “betwixt and between.”

Shadow organizing focuses on the way that situated elements (people, technologies, knowledge, infrastructures, society) intra-relate and acquire agency. Whilst organizing as the effect of intentional coordination, planning, and strategizing represents a well-established theorization, shadow organizing sheds light on what happen in the interstices of intentional and structured processes. The paper identifies the dimensions of shadow organizing as performativity, liminality, and secrecy.

The passage from elements in interaction to intra-acting relations that form elements is a challenge both for theory and methodology. To face this challenge, metaphorical thinking proves useful since it enhances scholars’ imaginations and emotional participation.

Means for securing fabric to a wing or the like comprises a rib or similar member having an up‐right limb a, Fig. 2, of U‐section and horizontal flanges b with downturned ends d, the limb a being traversed at intervals by eyelets such as c, rivets or the like, around which the fabric securing cord/ is passed as shown in Fig. 1 so that the fabric is pulled down partially into the concavity in the virtue of their' nature or construction numerous small perforations or interstices spaced substantially uniformly over the area so as virtually to render the area uniformly porous to air. Perforations or interstices of the order of 420 per square inch are stated to be suitable to give the desired porosity. As shown, an aero‐engine 3 drives a centrifugal blower 5 to suck air through the wing covering, ducts 7, 6 having guide vanes 8, and exhaust it above the fuselage. Passages are formed in the wing beneath the covering and are provided with valves 13 operable together or severally. According to the first Provisional Specification, porous fabric may be stretched over closely perforated sheet‐metal.

The purpose of this paper is to propose a new recognition algorithm on quadratic local extremum for fabric density recognition.

The density wave is established to correctly detect density by searching local extremes. The gray wave of each line in fabric image is extracted first. The derivation of gray wave is calculated, extreme waves including all true extreme values and false extreme values are obtained. And then the second derivative of extreme waves are calculated and the result makes local correction. The density wave, which can represent position and quantity of yarn and interstice, is established. According to the resolution and size parameters of image, the function of density with density wave statistics is given.

The experiment and analysis proved that the method proposed can detect fabric density simply and successfully with less calculation and no image preprocessing.

The algorithm provides practical guidelines for fabric density detection and provides a new thought for fabric characteristic identification. Future work could be focused on the development of methods for the automatic algorithm with color fabrics.

The algorithm based on quadratic local extremum presented in this paper is a new method to successfully detect fabric density and can be applied to the recognition for other categories of clothing fabrics and images.

This paper aims to examine the transformation of the concept of cultural tourism within the sociopolitical empowerments, changes of visual realms and normative contexts, which is embedded within museums as institutions.

These discussions will be conceptualized through investigating the shifts in the metamorphosis of the architectural vocabulary of Egypt's museums between nineteenth and twentieth centuries. This analysis will be highlighted through connecting both the notion of the “tourist reflexivity” of John Urry and Jonas Larsen in The Tourist Gaze 3.0 (2011) and the notion of the “interstitial spaces” and “new internationalism” of Homi Bhabha in The Location of Culture (1994). The analysis expands to interrogate these two notions as prelude for reflecting on representations of colonial and postcolonial museums in Egypt, starting from the Museum of Egyptian Antiquities, Cairo (c. 1863) to the most recent, the Egyptian Grand Museum, Cairo (c. 2002).

The analysis revealed that while colonial museums endeavored to stage external cultural authority and postcolonial ones staged traditions' liminality through “New internationalism”, they created spatiotemporal interstices. This finding, while is a timely example with the rising global cultural encounters that emerged during this transformative age, it challenges the collective imaginations of architects to liberate from traditional nationalism.

The paper offers novel theoretical and architectural analysis of Egypt's museums through the exigency of nationalism and “new internationalism”. The encounter between both notions is a timely example given the recent involvements by the “Modern State” and the recent pandemic upheaval that revealed the inevitability of globalism and the discursivity of such notions.

People in all cultures of the world classify other people most readily in easily identifiable categories. Examples of such categories are race, gender, economic, and physical difference. These categories make the world intelligible because they assign roles and functions attached to the individuals that fill the category. Racial, gender, and other categories that reflect difference may change over time as to the meaning and assigned roles and functions, but the very fact of them being a criterion for classification remains rather unchallenged. Yet the very fact of classification may question whether individuals with disabilities belong to the most essential of all categories, the human category. With classification, a statement of exclusion or inclusion in the human category is imminent.

The purpose of this study is to determine the thermal behavior of a hemispherical electronic device contained in a concentric hemispherical enclosure, cooled by means of free convection through a porous medium saturated with a water–copper nanofluid. Influence of various parameters on the thermal state of this device is processed in this work. The high power generated by the dome leads to a Rayleigh number varying in the 5.2 × 10⁷-7.29 × 10¹⁰ range. The volume fraction of the monophasic nanofluid varies between 0 (pure water) and 10 per cent while the base of the hemispherical cavity (disc) is inclined between 0° (horizontal disc with dome facing upward) and 180° (horizontal disc with dome facing downward).

The three-dimensional numerical approach is carried out by means of the volume control method associated to the SIMPLE algorithm.

The work shows that the average temperature of the active component increases with the Rayleigh number according to a conventional law of the power type. The increase in the angle of inclination also goes with a systematic rise in the average temperature. However, increasing the ratio of the solid–fluid thermal conductivities decreases the average temperature of the component, given the respective contributions of the conductive and natural convective phenomena occurring through the nanofluid saturated porous media. The values of this ratio vary in this work between 0 (interstice between the two hemispheres without porous medium) and 70.

The correlation proposed in this work allows to calculate the temperature of the active electronic component for all the combinations of the four influence parameters which vary in wide ranges.

The main purpose of this work is to quantify the convective heat transfer occurring between two inclined and concentric hemispheres.

The inner one is an electronic assembly generating a constant heat flux during operation. The outer hemisphere is maintained isothermal at cold temperature. The interstitial space is air-filled. The base of the equipment can be inclined with respect to the horizontal plane by an angle ranging from 0° (horizontal position with dome faced upwards) to 180° (horizontal position with dome faced downwards).

Nusselt–Rayleigh correlations are proposed for several configurations obtained by varying the generated power and the base inclination. The large resulting Rayleigh number ranging between 2.4 × 10⁵ and 1.7 × 10⁷ allows using these new and original correlations in various engineering fields, such as electronics in the present work. The calculations are realized by means of a 3D numerical approach based on the finite volume method.

The geometry and the thermal boundary conditions considered in the present survey are suitable for applications in many engineering areas.

Research pertaining to African-American women in academe is scant. Narrowing the focus to a specific segment of this population, such as those in the professoriate, is even more limited. Much of the available scholarship responding to the realities of African-American women’s work and lives in higher education revolves around the emotional, cultural, professional, and epistemic violence endured at the intersections of multiple systems of oppression, and the ways in which these women cope and resist. Less is known beyond these various coping strategies. Literature that responds to the complexities of Christianity and privilege, particularly in regards to directives for institutional diversity remains inconsistently addressed. The ways in which multiple forms of the Judeo-Christian faith influence experiences within differing higher educational settings is limited. Investigating the materiality that occurs in the interstices of these differing, yet interrelated, conversations has significant import for multiple dimensions of Black higher education. The present chapter questions the potential influence Judeo-Christian African-American women faculty have on diverse student engagement at historically Black colleges and universities.