The widespread use of technology in the digital age continually shapes how individuals consume knowledge and learn. In the digital age, ideas are shared and represented in multiple formats and through the integration of multiple modes. Technological advances, coupled with considerations of the changing needs of today’s learners, call for exploring new directions for multimodal teaching and learning. Yet, society’s increasing reliance on, and use of, technologies for communication and learning has introduced expanded forms of meaning-making. Information and communication technologies (ICTs) and the online networks that are facilitated by their use encourage educators to transform the way education is delivered. Learning environments are in need of becoming transformed so students are able to use immersive technologies to expand their learning opportunities. This chapter explores emerging trends and pedagogies in multimodal learning that seek to take advantage of the digital tools, texts, and learning approaches that are continually shaping the ways learning occurs inside and outside of higher education.This chapter is outlined to highlight what is found in the literature on multimodal instruction, what findings were realized at eXploring the Future of Innovative Learning Environments (X-FILEs) workshops, and lastly how multimodal instruction can be used to transform the classroom of the future. Throughout this chapter, readers will get to know a student of the future, Juan Delgado. He attends a 4-year university in Dallas, Texas, and is majoring in Mechanical Engineering taking his Introduction to the Fundamentals of Science course. Each aspect of the learning process as it relates to multimodal instruction in 2023 is outlined through the experiences of Juan to situate the impact to learners.

Rates of attack of carbon steel and alloy steel by hydrogen at temperatures of 400°a nd 500°C. and pressures ranging from 340 to 1000 atm. were measured. The influences of exposure time, temperature, pressure, stress, carbon content, microstructure, and alloying elements on the rate of attack were investigated in order to gain insight into the mechanism of the process. The criteria of attack were the extent of damage to the microstructure as determined by metallographic examination, changes in mechanical properties, loss of carbon, and volume change of the specimen. The attack process was characterized by a temperature-dependent induction period followed by a period of rapid attack accompanied by extensive decarburization and structural damage. The final stage of the process was described by a slow rate of change of strength properties and carbon content, with no appreciable increase in structural damage. Mechanisms for the process were postulated, and the ratedetermining steps were ascertained.A.LTHOUGH THE deleterious effect of hydrogen in steel has long been recognized there has been little quantitative study of the reaction of high-pressure, high-temperature hydrogen gas with carbon steel and alloy steel. Moreover, the nature of the reaction is dependent upon the temperature, pressure, moisture content of the hydrogen, and other variables that have often been unrecognized and uncontrolled.At room temperature and at pressures above about 2000 atm. dry hydrogen will effectively embrittle steel without permanent damage to the microstructure ( 15). The degree of reversible embrittlement is a function of the hydrogen pressure, exposure time, exposure temperature, and chemical composition of the steel. In general, austenitic steels are much less susceptible to embrittlement than are ferritic steels. The resistance of the stainless steels to embrittlement is attibuted to the presence of a surface layer of chromium oxide (10). It is significant, however, that the diffusivity of hydrogen in austenitic steel is considerably less than its diffusivity in ferritic steel (5).Hydrogen attack of steel is characterized by permanent damage to the microstructure, as evidenced by fissures and enlarged grain boundaries, and by decarburization. This deterioration of the metal causes a marked reduction in both strength and ductility. Hydrogen attack of carbon steel is significant at temperatures above 200°C. and up to the transformation temperature, and at pressures above 25 atm. Below 200°C. it is unlikely that this phenomenon

A mathematical model of a through-circulation packed bed dryer is presented in this paper. The semitheontical model treats the case of constant rate drying in a deep bed of granular solids under initially uniform drying conditions. Experimental data for drying in superheated steam, mixtures of superheated steam and air, and air alone showed good agreement with predictions of the model.Based on t k model, a static optimization method is developed for optimal operation of a continuais through-circulation dryer subject to the inequality constraints of maximum permissible air-horsepower per unit bed area and maximum permissible local find moisture content in tk bed. A nonlinear capacity function is defined in terms of the independent drying variables and is maximized under the above nonlinear restraints.Wilde and Beightler (1) have recently described an Optimization technique, the differential algorithm, which seems particularly suited to the highly nonlinear problem of optimizing a through-circulation dryer. These dryers are desiped for the handling of particulate solids such as granulations, extrusions, etc., in the form of a packed bed. The bed is supported on a perforated plate or screen which is conveyed through the dryer (Figure 1 ) . An appropriate drying agent (hot air, superheated vapor, etc.) is circulated through the bed, usually by centrifugal fans. The dryer may be compartmentalized with each section having its own fan and capable of directing flow through the bed either upward or downward. The effective dryer length is made up by connecting one or more compartments in series. In the case of an existing dryer for which the thermodynamic state of the drying fluid is fixed, the drying time is a function of the fluid velocity, bed loading, and the particle characteristics.The conveyor speed, which is established by the drying time in a given dryer, need not be considered in the analysis. DRYING MODELFor purposes of analysis, the through-circulation dryer can be treated as a packed bed operating under the following conditions: adiabatic drying throughout the bed, plug flow of the fluid, uniform radial temperature distribution in the fluid, uniform and constant particle temperature distribution in the bed, uniform bed voidage, constant gas-solid heat transfer coefficient, and constant fluid transport properties.For the constant rate drying period, the fluid temperature and bed moisture content distribution equations are sufficient to describe the process. These may be obtained from solutions of the difFerentia1 ecergy equation for the gas phase and the coupled differential mass balance equation for the solid phase.Differential energy equation (gas phase)Subject to boundary conditions on moisture content and gas temperature, the solutions in dimensionless form are Gas-phase temperature distributionSolid-phase moisture content distributionThe volumetric heat transfer coefficient for the bed isFor a given value of 2. Equation (4) describes the local drying curve. When axial mixing can be considered negligible, E...

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Singularity theory is applied to a steady state heterogeneous fixed-bed reactor model in which backconduction of heat through the catalyst is assumed. A maximum of five solutions exist when either adiabatic or Danckwerts' boundary conditions are assumed for the catalyst temperature although heat loss at the bed inlet increases the exothermicity of the reaction required for five solutions to exist. An empirical uniqueness criteria for this model, based on the zero and infinite solid phase conductivity limiting cases, is presented.