A multi-purpose microprocessor-based electrochemical apparatus

A microprocessor-linked programmable calculator instrument is described. Current-voltage readings taken at predetermined intervals of time can be read, stored and passed to the calculator where they may be processed to yield Tafel slope data, ohmic drops, areas under curves (for cyclic voltammetry) or used in open-circuit decay calculations. The results may also be fed to a paper-tape punch for storage or graphplotting using a larger computer.     

The impact of focused degree projects in chemical engineering education on students’ research performance,retention, and efficacy

Recent reforms in engineering education have emerged to meet the changing needs of engineers, however sparse research exists that comprehensively assesses the outcomes associated with such engineering education efforts. Accordingly, there is an urgent need for educational approaches tied to assessing engineering students’ performance, retention, and impact.This study's purpose is to explore the relationship between sequential chemical engineering degree projects and students’ performance, engineering efficacy, multidisciplinarity, and retention. The projects for this education for chemical engineers research are thematically focused laboratory experiments embedded in a four-year chemical engineering program. Each project component is connected to the next, is increasingly complex as courses advanced, and is aligned with essential course content. This connectivity enables students to participate in logically sequenced experiments that culminate in well-developed senior laboratory projects. This study's educational impact was determined via comparison between seniors’ and freshmen’ performance, efficacy and retention.Results of this research indicate that the use of degree projects in chemical engineering education is impactful, resulting in students’ increased understanding of experimentation and course content; meaningful, resulting in statistically significant increased student chemical engineering efficacy; and engaging, resulting in students’ satisfaction with program impact, engagement with peers during experimentation, and dramatically increased student retention.     

State function-based flash specifications for open systems in the absence or presence of chemical reactions

Diverse engineering fields require flash calculations like isothermal flash, isenthalpic flash, and isentropic flash. They can be cast as minimization of a thermodynamic state function and solved by Michelsen's Q-function approach. Flash calculations for open systems, that is, systems where chemical potentials are specified instead of the mole numbers for some components, also belong to this scope. By analyzing the construction of Q-functions through Legendre transforms, we extend this approach to the flash for open systems in the absence or presence of chemical reactions, resulting in general formulations for various specifications. For systems without reactions, the classical framework using mole numbers as independent variables is employed; for those with reactions, the modified-RAND framework is employed. We present examples for open systems at constant temperature and pressure. Using the Q-function minimization, we can solve multicomponent nonreactive or reactive systems at a specified chemical potential with quadratic convergence over a wide range of conditions.     

Training the next generation of creative,innovative and adaptive scientists and engineers: The NSF Engineering Research Center for Biorenewable Chemicals (CBiRC) Research Experience for Undergraduates

Integrated chemical and biological processing systems that use biorenewable resources as feedstocks are critical to addressing the world's growing demand for carbon-based consumer products, and can make significant contributions to ensuring environmental sustainability. The United States National Science Foundation (NSF) Engineering Research Center (ERC)¹ for Biorenewable Chemicals (CBiRC)² provides educational programs that attract a diverse group of students into engineering fields to address the world's need to produce globally competitive college graduates capable of designing cost-competitive biorenewable chemicals. CBiRC provides a unique fusion of innovative interdisciplinary research and undergraduate educational opportunities through the CBiRC Research Experience for Undergraduates (REU) program. The REU is an intensive ten-week summer program where students not only learn laboratory research skills, but are also immersed in the interdisciplinary academic environment of the ERC through workshops, seminars, research thrust meetings, and interactions with CBiRC professional staff. In this article, we describe a novel evaluation-supported model for an interdisciplinary undergraduate research program in the field of biorenewable chemicals engineering, which encourages undergraduates to build upon basic research skills to propose creative, innovative, and adaptable solutions to chemical engineering problems.     

Zur Nutzung neuer Informationstechnologien im Chemieingenieurwesen (Stand und Entwicklungstrends)

Use of information technologies in chemical engineering (state of the art and trends) . Information saves energy, time and money. Data processing has developed very rapidly within recent years. The number of data bases and their volumes have multiplied. An end-user is initially confused when choosing a new system suitable for his purpose. At the chemical engineer's disposal are computing performance, data bases about special literature and physical properties, CAD for designing, process computers improve the running of production plants, simulations by computer and programmes, respectively, help to solve development problems without incurring any risk, thus lowering costs, and the new personal computers are programmable directly at the job. Engineers are still not as familiar with word processing and office communication as commercial people are. Steadily increasing speed of data transmission and higher data density reduce costs, e. g. by public data nets like EURONET or DATEX or private so-called ?inhouse nets”?. The commercial use of ?Bildschirmtext”? and ?Videotext”? has been started. Information about the new facilities enables the chemical engineer to choose the most effective systems for his work.     

CAPE in der Praxis — Möglichkeiten und Grenzen aus Nutzersicht

CAPE in Practice - Opportunities and Limits from the User's Point of View . CAPE tools comprise computer based tools and methods for the design of chemical processes - the use of which is indispensable in modern chemical engineering. This paper discusses the degree to which CAPE is already applied and whether limitations exist. Within BASF, the CAPE framework is provided by the “ProcessNet”, which integrates numerous simulation and design tools. The engineer relies alternatively on inhouse or commercial software. The advantage of CAPE in terms of efficiency depends not only on complex programs, but also to a large extent on the multiple use of intermediate data and program modules. The ProcessNet also features a hierarchical file structure to support the engineer's desktop management. The CAPE environment is being continuously improved. The main constraints on CAPE today are, for example, the missing link between fluid and solid applications, a deficit in data management and the poor state of development of advanced or special programs. The progress of research in this area is followed with great interest.     

The use of differential scanning calorimetry to study polymer crystallization kinetics

A Tektronix-31 programmable calculator interfaced to a Perkin Elmer differential scanning calorimeter, model 2, substantially improves the accuracy of measuring the time-dependent development of the degree of crystallinity (× 10) and hence improves the quality of the rate data. Storing energy flow data at preset time intervals directly into the memory of the calculator improves the accuracy of the measurement of time, and enables the evaluation of the onset of crystallization and the baseline of the calorimeter initially. This substantially improves the measurement of the degree of crystallinity developing with time by integrating the energy flow data over the time interval from the onset of crystallization. Polyethylene samples are studied since their rate constants have a marked temperature dependence which enables the accuracy of the analytical procedure to be assessed. Primary and secondary crystallization processes are separated.     

Analysing gas well production data using a simplified decline curve analysis method

Decline curves are one of the most extensively used forms of data analysis employed in evaluating gas reserves and predicting future production. The parameters determined from the classical fit of historical data can be used to predict future production and the most popular and widely accepted method is Arp's equation. In the present work, simple-to-use method, which is easier than existing approaches, less complicated with fewer calculations, is formulated to arrive at an appropriate estimation of nominal (initial) decline rate, and the Arp's decline-curve exponent. The results can be used in follow-up calculations for analysis of past trends of decline in production performance for gas wells as well as reservoirs. Using this method is quite simple and accurate to generate the coefficients of the equations instead of opting for ready-generated coefficients with uncertainty. The engineers can easily develop their own computer program to compute the coefficients and hence obtain the solution for gas reserves and production performance in reservoirs.     

Role of inorganic and theoretical chemistry in ceramics: past,present, and future

Abstract

Theoretical inorganic chemistry has evolved since Professor Mellor's time to include a new generation of quantum mechanics based calculational methods to understand and predict chemical reaction pathways. Semi-empirical molecular orbital (MO) calculations have been used in the fields of glass and silica structure analysis, fracture mechanics, sol–gel processing of net shape optics, porous matrixes for hybrid optics, sensors, and tissue engineering scaffolds. Applications of MO calculations in biomaterials interface reactions, biomimetics, and biomineralisation have also been made. Future directions for use of theoretical inorganic chemistry in the ceramic industry are forecast.     

Among the trends for a modern chemical engineering,the third paradigm: The time and length multiscale approach as an efficient tool for process intensification and product design and engineering

To respond to the changing needs of the chemical and related industries in order both to meet today's economy demands and to remain competitive in global trade, a modern chemical engineering is vital to satisfy both the market requirements for specific nano and microscale end-use properties of products, and the social and environmental constraints of industrial meso and macroscale processes. Thus an integrated system approach of complex multidisciplinary, non-linear, non-equilibrium processes and phenomena occurring on different length and time scales of the supply chain is required. That is, a good understanding of how phenomena at a smaller length-scale relates to properties and behaviour at a longer length-scale is necessary (from the molecular-scale to the production-scales). This has been defined as the triplet “molecular Processes-Product-Process (3PE)” integrated multiscale approach of chemical engineering. Indeed a modern chemical engineering can be summarized by four main objectives: (1) Increase productivity and selectivity through intensification of intelligent operations and a multiscale approach to processes control: nano and micro-tailoring of materials with controlled structure. (2) Design novel equipment based on scientific principles and new production methods: process intensification using multifunctional reactors and micro-engineering for micro structured equipment. (3) Manufacturing end-use properties to synthesize structured products, combining several functions required by the customer with a special emphasis on complex fluids and solid technology, necessating molecular modeling, polymorph prediction and sensor development. (4) Implement multiscale application of computational chemical engineering modeling and simulation to real-life situations from the molecular-scale to the production-scale, e.g., in order to understand how phenomena at a smaller length-scale relate to properties and behaviour at a longer length-scale. The presentation will emphasize the 3PE multiscale approach of chemical engineering for investigations in the previous objectives and on its success due to the today's considerable progress in the use of scientific instrumentation, in modeling, simulation and computer-aided tools, and in the systematic design methods.     

高温高压下氯化钠水溶液的热力学(I)——在373—573K及0.1—100MPa条件下NaCI-H_2O体系的热力学性质

本文提出了一个简易的热力学方程式,式中仅包含一个表示长程作用力的静电项,再加上一个表示两粒子间的短程作用项,即可用以计算温度为373—573K,压力为0.1—100MPa、氯化钠浓度为0—10.4mol/kgH_2O的水溶液中氯化钠和水两者的活度系数,计算简便,易于推广使用.     

能源化学工程专业无机及分析化学教学改革的探究

针对无机及分析化学教学在培养学生创新能力的作用,本文从无机及分析化学实践教学经验出发,对我校能源化学工程专业的无极及分析化学课程教学改革进行了探究。通过优化教学内容、激发学生兴趣、利用各种教学方法、培养学生能力以及适应专业要求方面的改革,有望培养能源化学工程专业创新型人才,以满足社会及经济的发展对人才的需求和素质教育的要求,达到改善教学质量及提高学生创新能力的目的。     

John M. Prausnitz: Bridging abstractions and realities

This Founders Tribute issue honors John Prausnitz as an exceptional intellectual leader, scholar, and educator and summarizes his impact on chemical engineering. John's early vision of connecting fundamental molecular theory to practical thermodynamic applications with Molecular Thermodynamics was an essential element in our profession's paradigm shift from empiricism to engineering science. John's writings and lectures have transformed our core knowledge and guided its utilization into areas well outside traditional engineering bounds. Further, he has vigorously advocated for technology to be considered in the context of all of life and as a human enterprise. Finally, John's personal interactions across generations and disciplines have inspired the personal and professional development of a vast community of students, coworkers, and colleagues. In countless ways, John Prausnitz has influenced the contemporary foundation and functioning of chemical engineering and of realms beyond. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2675–2688, 2015     

Wärmetransformatoren für die Chemische Industrie aus der Sicht des Anwenders

Absorption heat transformers for the chemical industry as seen from a user's point of view. Absorption heat transformers can transfer waste heat, that could not hitherto be reused, to a higher temperature level. This is of special interest for the chemical industry, where there is both waste heat available at temperatures below 100°C and a demand for heat at 120 to 150°C. Though absorption heat transformers are able to recycle only a part of the total waste heat, they only need a negligible amount of additional, expensive exergy. The present status of development and advantages and disadvantages of the concept are discussed from a user's point of view. In view of the present low price of energy, special attention is given to economic considerations.     

Chemical Engineers for the 21st Century – Challenges for University Education

At the beginning of the 21st century, the education of chemical and process engineers is facing enormous challenges. The number of new students has dropped substantially since the early 1990s. The globalization of the world's economy has altered the working environment and the job market for chemical engineers. The areas in which chemical engineers are active now extend far beyond the boundaries of the chemical industry. As a result, universities are having to compete much more, not only for undergraduate and graduate research students but also in order to keep courses and even departments open. This paper aims to shed some light on the current situation at the universities, the changes in the conditions and job environment in the chemical engineering field, and the demands being placed on tomorrow's chemical and process engineers and on the education they receive. From an organizational point of view, it is important that the universities actively participate in and influence this ongoing process of change. In terms of course content, increasing emphasis must be placed on teaching students modern, relevant engineering knowledge and methodological and systematic skills, as well as those aspects of their education that are relevant for the ever more flexible, interdisciplinary and intercultural nature of chemical engineering work. Elements that could usefully contribute include support for study abroad programs and the provision of broad, high‐quality extra‐curricular studies. Despite the changes that have occurred, such as the introduction of new (bachelor and master) degrees, it is essential that the universities retain their characteristic and established profiles. At the same time, it is important to make the universities more accessible to well‐qualified graduates from Germany's Fachhochschulen (universities of applied science).     

PROCESS CONTROL PERSPECTIVE FOR PROCESS ANALYTICAL TECHNOLOGY: INTEGRATION OF CHEMICAL ENGINEERING PRACTICE INTO SEMICONDUCTOR AND PHARMACEUTICAL INDUSTRIES

FDA's Process Analytical Technology (PAT) initiative provides an unprecedented opportunity for chemical engineers to play significant roles in the pharmaceutical industry. In this article, the authors provide their perspectives on (1) the need for chemical engineering principles in pharmaceutical development for a thorough process understanding; (2) applications of chemical engineering principles to meet the challenges from the semiconductor and pharmaceutical industries; and (3) the integration of chemical engineering practice into the semiconductor and pharmaceutical industries to achieve process understanding and the desired state of quality-by-design. A real-world case study from the semiconductor industry is presented to demonstrate how a classic chemical engineering concept, mixing homogeneity, can be implemented by inducing forced flow to ensure an excellent copper electrochemical plating process performance and to improve product quality substantially. Further, a case study of brake system design is discussed with the concept of Dr. Taguchi's robust engineering design to illustrate how quality-by-design can be achieved through appropriate experimental design, in conjunction with the discussion on the concept of quality-by-design in pharmaceuticals. Third, a case study of freeze-dried sodium ethacrynate is presented to demonstrate the vital importance of controlling the processing factors to achieve the desired product stability. Finally, the problems of the current pharmaceutical manufacturing mode, the opportunities and engineering challenges during implementation of PAT in the pharmaceutical industry, and the role of chemical engineering in implementation of PAT is discussed in detail.     

Trennleistung von Dünnschichtverdampfern

The evaporation process has recently gained new momentum through special applications in chemical engineering and especially in environmental engineering, e.g. in the recovery of materials of value from liquid production residues. Thin‐layer evaporators with rotating wipers are particularly suitable for such tasks if the products of interest are thermally unstable or are prone to crusting. If these applications involve distillation‐type separation then a knowledge of the expected separation effect is important for calculations. This article aims to make a contribution to this topic. It is based on experimental studies performed on a laboratory‐scale thin‐layer evaporator and on earlier treatments of the theory of distillation in thin‐layer evaporators with a mechanically generated liquid film.     

Estimation of molecular weight distribution parameters for free-radical polymerization

A method is described which allows the precise estimation of molecular weight distribution parameters p and A which pertain to free-radical polymerizations. Thus, expressions are developed which allow the estimation of (1 ? p) by means of a programmable calculator using molecular weight distribution data derived from GPC. Values of A may subsequently be calculated by means of a plot of one of the expressions given. Values of (1 ? p) and A obtained in this paper were checked using theoretical values as well as by a comparison between calculated and observed values. The agreement between calculated and theoretical or experimental values indicates that the method presented for the estimation of (1 ? p) and A is both reliable and relatively rapid. Previously reported methods for the estimation of (1 ? p) and A have involved curve-fitting trial calculations as well as more precise interpolation procedures. However, the latter are based on single-peak maximum values.     

The Diffusional Boundary Layer: Some Implications for the Dyeing Technologist

This paper was presented at the Second AA TCC Inter–national Dyeing Symposium held at the Marriott Twin Bridges Hotel, Washington, D. C., USA, on 5–6 May 1980. “mathematics are either pure or mixed. and as for the mixed mathematics, I may only make this prediction, that there cannot fail to be more kinds of them, as nature grows further disclosed.” Modern computational devices of the 1980s, e. g., the new card programmable “pocket” calculators, provide the dyeing technologist with a useful and inexpensive means of reducing the formidability of computation associated with the use of complex diffusion equations. Armed with these modern tools, the dyeing technologist of the 1980s can use the previously imposing “boundary layer”diffusion equations of Newman or Crank in a purely chemical engineering way – coupled with statistical techniques – to estimate the optimum apparent value of L simultaneously with the optimum apparent diffusion coefficient. Analysis of real dyeing systems in terms of these fundamental physico–chemical parameters, although impossible to carry out to rigorous completion, nevertheless can help to improve the modern technologist's awareness of the influence of flow rate on level–ness in commercial dyeing processes.     

Determination of the glass transition of polymer by the autovibron

The automated Rheovibron (Autovibron) has been useful for determining the glass transition behavior of polymers. The standard (manual Rheovibron viscoelastometer has been used sufficiently small intervals, and so, some accuracy on transition location must be sacrificed when the temperature intervals are taken 5 to 10°C apart. However, the Autovibron can be observed over very small temperature intervals (<1.5°C)), which essentially provide a continous monitoring of the changes in storage modulus, loss modulus, and tan δ. An improved accuracy and sensitivity of the Autovibron are provided by a combination of multiprogrammer, programmable calculator, and lock-in analyzer. The Autovibron are provided by a combination of multiprogrammer, programmable calculator, and lock-in analyzer. The Autovibron shows a good capability for dynamic thermomechanometry. The glass transition bility for dynamic thermomechnometry. The glass transition of polymers can be determined by analyzing the loss tangent peak. The maximum value in loss tangent, peak temperature, and the newly introduced terms, ΔT₁ and ΔT₂ which indicate the widths of tan δ peak, are useful indicators of the glass transition. The ΔT₁ and ΔT₂ show the distribution of the glass transition and are related to order and crystallinity in the structure.