Chemical Engineering Commons^™

A Blend Conducting Membranes For Direct Methanol Fuel Cells, Lei Li, Jun Zhang, Hong Wu, Yu-Xin Wang

Journal of Electrochemistry

An attempt was made to modify membranes for direct methanol fuel cells by blending Nafion or polystyrene sulfonic acid (PSSA) with polyvinylidene fluoride (PVDF) from their solutions. The proton conductivity and methanol barrier property as a function of the membrane compositions are discussed. Compared with the Nafion 117 membrane, the PVDF-Nafion blend membranes with 25 wt% of Nafion showed a decrease in the conductivity by about 2 orders of magnitude, and the methanol barrier properties increased about 3 orders of magnitude. If the ratio (σ/P) is adopted to characterize the performance of the membrane, the PVDF-PSSA and PVDF-Nafiion blend membranes …

Genome-Wide Screening For Trait Conferring Genes Using Dna Microarrays, R. T. Gill, S. Wildt, Y. T. Yang, S. Ziesman, G. Stephanopoulos

Dartmouth Scholarship

We report a DNA microarray-based method for genome-wide monitoring of competitively grown transformants to identify genes whose overexpression confers a specific cellular phenotype. Whereas transcriptional profiling identifies differentially expressed genes that are correlated with particular aspects of the cellular phenotype, this functional genomics approach determines genes that result in a specific physiology. This parallel gene-trait mapping method consists of transforming a strain with a genomic library, enriching the cell population in transformants containing the trait conferring gene(s), and finally using DNA microarrays to simultaneously isolate and identify the enriched gene inserts. Various methods of enrichment can be used; here, genes …

Characterization Of Structural Changes In Thermally Enhanced Kevlar-29® Fiber, James W. Downing Jr.

Theses and Dissertations

The purpose of this exploratory investigation was to elucidate the structural mechanism accounting for the enhanced compressive properties of heat-treated Kevlar-29® fibers. A novel theory was set forth that hydrogen bond disruption and concurrent misorientation of crystallites may account for the observed augmentation of compressive properties. To examine the said theory, virgin Kevlar-29® fibers were characterized by Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) in an effort to determine if crosslinking and/or hydrogen bond disruption was responsible for the improved behavior in compression. Additionally, Kevlar-29® fibers that had been exposed to treatment temperatures of 400, 440, and 470 °C …

The Fission Properties Of Curium Separated From Spent Nuclear Fuel, William Culbreth, Elizabeth Bakker, Jason Viggato

Separations Campaign (TRP)

Curium poses special problems in the chemical preparation of spent nuclear fuel for transmutation. Once separated from the other minor actinides, the seven curium isotopes in spent fuel can lead to nuclear fission with the subsequent release of a large amount of radiation. Several isotopes of curium also generate a significant amount of heat by radioactive decay. Sustained fission can be avoided by preventing the accumulation by more that a critical mass of curium. The heat generation of curium presents even more restriction on the mass of curium that can safely be contained in one location.

To analyze the nuclear …

Melting At Alkyl Side Chain Comb Polymer Interfaces, K. S. Gautam, Ali Dhinojwala

College of Polymer Science and Polymer Engineering

Infrared visible sum frequency generation (SFG) spectroscopy has been used to study structure and melting transition temperatures of alkyl-side chain-acrylate comb polymers at air and solid interfaces. At the air interface, the SFG spectra show methyl bands and two transitions are observed: the first, near the bulk melting temperature, T-m, and the second 10-20degreesC higher than T-m. The shorter the alkyl side chain, the larger the difference between the two transition temperatures. In contrast, methylene bands are observed at sapphire interface with a single transition near T-m (C18).

Modeling And Experimental Verification Of Growth Of An Axisymmetric Cylindrical Rod By Three-Dimensional Laser-Induced Chemical Vapor Deposition, Qing Chen

Doctoral Dissertations

Three-dimensional laser-induced chemical vapor deposition (3D-LCVD) is a recently developed micro-manufacturing process that holds great potential for the production of complex microstructures with high aspect ratio. A laser beam is focused through a vacuum chamber window onto a movable substrate. The heat from the laser at or near the focal spot on the substrate induces the decomposition reaction of precursor gas in the chamber. As a result, solid-phase reaction products are deposited on the substrate to form the microstructure. In this dissertation, a numerical model is developed for simulating kinetically-limited growth of an axisymmetric cylindrical rod by pre-specifying the surface …

Motion Of Droplets Along Thin Fibers With Temperature Gradient, Alexander L. Yarin, Wenxia Liu, Darrell Hyson Reneker

College of Polymer Science and Polymer Engineering

Liquid n-decane, n-undecane, n-dodecane, and n-hexadecane formed tiny symmetrical droplets on a partially wettable cylindrical fiber. When a temperature gradient was created along the fiber, the droplets began to move along the fiber toward the cold region. An explanation of the phenomenon is related to the thermocapillary motion. Other possible mechanisms were ruled out. The theoretical results and experimental data agree reasonably well. (C) 2002 American Institute of Physics.

Non-Classical Level Control Of The Utc Distillation Column, Mevan Ranasinghe

Honors Theses

This paper researches the enhancement of accuracy for level control for an operational distillation column. This was achieved through an analysis of both controller and sensor components. The UTC distillation column reboiler level control, like any control system, has multiple sources of error resulting in increased imprecision and inaccuracy. Several fundamental inaccuracies in processing of data were identified and then minimized by the introduction of a non-linear mathematical model prior to any actual controller development. This provides more accurate level measurement and a base for developing accurate controllers.In exploring the effectiveness of alternative controllers, two non-classical controllers are considered in …

Integrating Passenger And Modulo As Learning Tools For Collaborative Engineering Education, Kalamullah Ramli, Frank Schwarz, Stefan Werner, A Halim Shamsuddin, Axel Hunger

Makara Journal of Technology

The University of Indonesia (UI), Gerhard Mercator University (GMU), the Universiti Kebangsaan Malaysia (UKM) have agreed to cooperate as partners to develop a joint bachelor (3+1) and masters (1+1) degree, and collaborate in the research fi elds of multimedia- and internet-based learning and application level active networks. This paper describes the introduction of the Offshore Project and the extending of information technology applications to the partner institutions in this international cooperation which would very much enhance the operations of the new initiative in engineering education, which could provide students in far distance with more fl exible learning environment.

Cfd Of Multiphase Flow In Packed-Bed Reactors: Ii. Results And Applications, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Numerical Simulations of Multiphase Flow using the K-Fluid CFD Model Described in Part I of This Issue Are Presented for Packed Beds at Various Operating Conditions. Both Steady-State and Unsteady-State (E.g., Periodic Operation) Feed Conditions Were Studied Numerically. Predictions of the K-Fluid CFD Model Are Comparable with the Experimental Data in the Literature for Liquid Upflow in a Cylindrical Packed Bed. in Addition to the Mean Porosity and the Longitudinally Averaged Radial Porosity Profile, the Variance of the Porosity Distribution is Needed for Predicting the Probability Density Function of the Sectional Flow Velocity. in the Trickling Flow Regime, the K-Fluid …

Cfd Of Multiphase Flow In Packed-Bed Reactors: I. K-Fluid Modeling Issues, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Eulerian K-Fluid CFD Model Was Used to Simulate the Macroscale Multiphase Flow in Packed Beds. the Geometric Complexity of the Bed Structure is Resolved by Statistically Describing the Porosity Distribution. the Complicated Multiphase Interactions Are Computed using the Ergun Type of Formula Developed based on Bench-Scale Hydrodynamic Experiments. the Work is Presented in Two Sequential Articles. Part I Discusses Implementation Issues of the K-Fluid CFD Model for Packed Beds. the Drag Exchange Coefficients Are Obtained from the Model of Holub Et Al. for the Particle-Fluid Interfaces Xks and from the Model of Attou Et Al. (1999) for the Gas …

Study Effect Of Salt Washing Process On Content And Iodium Stability Of Salt, Nelson Saksono

Makara Journal of Technology

Effect of Salt Washing Process on Content and Iodium Stability of Salt. Salt washing process should increase the salt quality. It should clean the salt from sludge or clay and also reduce the impurity compound such as Mg, Ca and the reductor content. The objective of these reseach is to assess the effect of washing process on the content og hygroscopic impurities compound (Ca and Mg), and reductor content of salt. The research also investigate the water absorbing, pH, KIO3 content as function of time to obtain effect of washing process on KIO3 stability in salt. The experiment result shows …

Object Classfification In Computer Vision With Discriminant Analysis, Amir Hamzahan

Makara Journal of Technology

A robotic sensor system is always supported by a computer system called ‘computer vision’. The important concept of computer vision is object classfifi cation. In this study two algorithms for object classifi cation in this system will be compared. Firstly, A simple method that do not need complex computation and that considered as an informal method is called binary tree decision structure. This method is based on modest caracteristic decriptors of an object such as vertical line, horizontal line or ellipse line. Unfortunately this method has weakness in recognize an image that contaminated by a noise. Secondly, a more formal …

Making Alloys (Ti1 - Xalx) N Using Plasma Cvd Technique From Alcl3 Powder, H2 And N2 Gas ,With Solvent Ticl4, Keba Moto

Makara Journal of Technology

The substitution of Ti atoms by Al atoms in TiN lattice sites to form (Ti1-xAlx)N is clearly demonstrated by the coatings which were deposited on steel substrate and using plasma CVD technique. The presence of Al atoms in TiN lattice site is shown by means of XRD and EDX techniques: lattice parameters decreasing of TiN as the fraction of Al increases (XRD) and precipitation of hexagonal AlN phase (XRD) as the fraction of Al exceeding 0.8 (EDX). The hardness of these coating are just around 30 GPa, which is beyond the values reported in literatures.

Effects Of 0.25 % Mo (Molybdenum) Which Is Contained In The Ductile Cast Iron On Mechanical Properties Of Austempered Ductile Iron (Adi)., Nukman Nukman, Bustanul Arifin, Bambang Sugiarto

Makara Journal of Technology

The aim of this research is to investigate the effects of 0.25 % Mo (Molybdenum) which is contained in the ductile cast iron on mechanical properties of Austempered Ductile Iron (ADI). The various temperatures and the holding times are used in the heat treatment processes. Using a given 0.25 % Mo in the ductile iron, ADI's alloyed developes a higher ultimate tensile stress value and decreases the elongation if we compare with the as cast (non alloy ductile iron). The higher impact energy value obtained at 9000 C austenization and 375o C austempering temperatures during 60 minutes holding times. The …

The Manufacturing Properties Of Galvanised Steel Sheet With Hexagonal And Tetragonal Network Of Circle Holes, Rahmat Saptono

Makara Journal of Technology

Galvanized steel sheet of 0.8 mm in thickness was drilled with circle holes of 2.5 mm diameter and spacing arranged in tetragonal and hexagonal pattern. The manufacturing properties of specimen were studied through drawing and stretching simulative test. It was concluded from the results that, at high ratio of punch to hole diameter (40/2.5), the drawing properties (LDR) of both square and hexagonal perforated sheet were slightly lower than that of solid sheet, while hexagonal perforated showing LDR somewhat higher than the square one. The stretching properties (LDH) of sheet, however, were much lower than that of solid sheet while …

Develops The Software Of Dsp Processor For The Cdma Circuitry, Arman Djohan D.

Makara Journal of Technology

This research develops the software of DSP Processor type TMS320C54X for the CDMA circuitry. This research apply two algorithms namely Mathematic Algorithm and table lookup Algorithm. From both algorithms, the research examine what algorithm have the fasted processing time and the smallest memory occupation. From the examination results the Mathematic Algorithm have 20.62 milliseconds processing time and the Table lookup algorithm have 14.08 milliseconds processing time. The Table lookup algorithm have the fastest processing time because the Matematic algorithm need the rounding process of the fi gure. Eventhough such processing time is not exceed from the 125 millisecond of delay …

Ethylene Oxide And Propylene Oxide Random Copolymer/Sodium Chloride Aqueous Two-Phase Systems: Wetting And Adsorption On Dodecyl-Agarose And Polystyrene, Yingqing Huang, Daniel Forciniti

Chemical and Biochemical Engineering Faculty Research & Creative Works

Liquid/liquid partition chromatography is a mild yet powerful separation method for a variety of biological materials. This work demonstrates that it should be feasible to immobilize an ethylene oxide-propylene oxide (EO/PO) random copolymer solution and to use a solution of NaCl equilibrated against the polymer solution as the mobile-phase (poly (EO-PO) [P(EO-PO)] and NaCl form two aqueous phases known as aqueous two-phase systems). Three random copolymers with different molecular weights and EO/PO ratios were used. Dodecyl-agarose and polystyrene were tested as possible supports. The wetting energies of the aqueous two-phase systems on these two kinds of surfaces were calculated as …

Thermal Analysis Of Fly Ashes Sourced From European Non-Blended Coals, Kenneth T. Stanton, Mark R. Towler, Patrick Mooney, Robert G. Hill, Xavier Querol

Chemical and Biochemical Engineering Faculty Research & Creative Works

Fly ashes exist as a mixture of major amorphous phases and minor crystalline phases. For commercial applications, such as in concretes and for the production of zeolites, it would be desirable to be able to predict the reactivity of fly ashes. The amorphous phase dominates degradation behaviour, because glasses have a higher potential energy than the equivalent crystal structure and the variation of bond angles and distances in a glass make the bond breakage easier. Despite the large quantities of fly ash produced annually by coal-burning power plants, there have been very few studies investigating the microstructure and composition of …

Remote Resonant-Circuit Analyte Sensing Apparatus With Sensing Structure And Associated Method Of Sensing, Craig A. Grimes

Chemical and Materials Engineering Faculty Patents

A resonant sensing apparatus for operative arrangement within a test environment to sense an analyte. A sensing structure is included having an antenna in electrical communication with a resonant circuit and a structural element made of a material that selectively responds to the analyte. This sensing structure will resonate at a particular characteristic resonant frequency in the presence of an applied interrogation electromagnetic field and the analyte upon the occurrence of the selective response. A receiver is used for remotely identifying a value for the characteristic resonant frequency by measuring a plurality of values for electromagnetic emission intensity of the …

Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler

Papers in Thermal Mechanics

Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …

Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler

Papers in Thermal Mechanics

Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …

Preliminary Study On Direct Ethanol Fuel Cell, Shu-Qin Song, Li-Kang Chen, Jian-Guo Liu, Zhao-Bin Wei, Qin Xin

Journal of Electrochemistry

The performance of a direct ethanol fuel cell based on Nafion115 was reported.PtRu/C and Pt/C were used as ethanol anode and oxygen cathode catalysts in a single cell of size 9 cm² .The effects of temperature, oxygen pressure, the flow rate of ethanol, and oxygen, and ethanol concentration were tentatively studied. The experimental results showed that the cell open circuit voltage 0.608 V, the cell voltage 0.329 V at 50 mA/cm², and the peak power density 19.25 mW/cm² were reached under the conditions of T_cell =85 ℃, P_O2 =0.5 MPa, C_ethanol =1.0 mol/L …

Electrosynthesis Of Glyoxylic Acid In A Packed Bed Reactor, Jin-Hong Fan, Jun Li, Yu-Zhong Su, Hao-Qi Gao

Journal of Electrochemistry

Glyoxylic acid was produced by electroreduction of oxalic acid in a packed bed reator. The cathodic and anodic electrolytes were super-saturated oxalic and hydrochloric acid aqueous solutions separated by a super-acid ion-exchange membrane. The current efficiency and yield of glyoxylic acid were studied under different structured packed bed reactors and different electrode materials, temperatures and current densities. The results indicated that the current efficiency of synthsis of glyoxylic acid was over 66.2% and the concentration of glyoxylic acid could reach 2.02% after 45min electrolysis with cathode of lead particles and anode of graphite board under conditions of temperature 32 ℃, …

Varying Current Electro-Synthesis Of Glyoxalic Acid In Pairs In The Fixed-Bed Electrolytic Cell, Yin-Sheng Chen, Xin-Sheng Zhang, Ying-Chun Dai, Wei-Kang Yuan

Journal of Electrochemistry

As for the process of the electro oxidation of glyoxal to glyoxalic acid, the electrolytic result of either fixed bed electrolytic cell or varying current electrolysis was better than that of either flat plate electrolytic cell or constant current electrolysis. The average current density of varying current electro synthesis of glyoxalic acid in pairs was 1535 A/m² and the current efficiency were 85.3% and 86.7% and the selectivity were 93.9% and 94.0% for the anodic oxidation and cathodal reduction respectively. The initial composition of anodic electrolyte was 7% glyoxal and 8% hydrochloric acid (W/W) and the cathodal electrolyte consisted …

Electrochemical Synthesis And Characterization Of The Nickel Electropolyurushiol Coordination Polymer, Feng Gao, Guo-Cai Shen, Jie-Yuan Tang, Wen-Gong Zhang

Journal of Electrochemistry

The nickel electropolyurushiol coordination polymer (EPU Ni²⁺) was obtained by the reaction between nickel chloride isopropyl alcohol solution with electropolyurushiol (EPU). The electrochemical polymerization of urushiol and the preparation of nickel electropolyurushiol coordination polymer were investigated. The coordination polymer was characterized by XPS, FT-IR, DMTA and AES methods, and its composition and structure were determined.The content of Ni²⁺ reached up to 7.5%. It was shown that there was certain coordination between Ni²⁺ and electropolyurushiol in the coordination polymer, thus cross-inks were formed. Therefore the glass transition temperature of the coordination polymer increased and heat resistance was …

Effect Of Catalyst Structure On Oxidative Dehydrogenation Of Ethane And Propane On Alumina-Supported Vanadia, Morris D. Argyle, Kaidong Chen, Alexis T. Bell, Enrique Iglesia

Faculty Publications

The catalytic properties of Al2O3-supported vanadia with a wide range of VOx surface density (1.4-34.2 V/nm2) and structure were examined for the oxidative dehydrogenation of ethane and propane. UV-visible and Raman spectra showed that vanadia is dispersed predominately as isolated monovanadate species below ~2.3 V/nm2. As surface densities increase, two-dimensional polyvanadates appear (2.3-7.0 V/nm2) along with increasing amounts of V2O5 crystallites at surface densities above 7.0 V/nm2. The rate constant for oxidative dehydrogenation (k1) and its ratio with alkane and alkene combustion (k2/k1 and k3/k1, respectively) were compared for both alkane reactants as a function of vanadia surface density. Propene …

Expression Of Active Human Factor Ix In Mammary Tissue And Of Milk Non Human Transgenic Mammals, William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

Recombinant Factor IX characterized by a high percentage of active protein can be obtained in the milk of transgenic animals that incorporate chimeric DNA molecules according to the present invention. Transgenic animals of the present invention are produced by introducing into developing embryos DNA that encodes Factor IX, such that the foreign DNA is stably incorporated in the DNA of germ line cells of the mature animal. Particularly efficient expression was accomplished using a chimeric construct comprising a mammary gland specific promoter, Factor IX cDNA that lacked the complete or any portion of the 5'-untranslated and 3'-untranslated region, which is …

Expression Of Active Human Factor Ix In Mammary Tissue And Of Milk Non Human Transgenic Mammals , William H. Velander, William N. Drohan

Papers in Biotechnology

Recombinant Factor IX characterized by a high percentage of active protein can be obtained in the milk of transgenic animals that incorporate chimeric DNA molecules according to the present invention. Transgenic animals of the present invention are produced by introducing into developing embryos DNA that encodes Factor IX, such that the foreign DNA is stably incorporated in the DNA of germ line cells of the mature animal. Particularly efficient expression was accomplished using a chimeric construct comprising a mammary gland specific promoter, Factor IX cDNA that lacked the complete or any portion of the 5'-untranslated and 3'-untranslated region, which is …

Studies On Use Of Carbon Slurry, A Waste From Fertilizer Plant, In Treatment Of Waste Water, Sanjay Tewari

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

"Non biodegradable materials like heavy metals, refractory organics are not removed during the conventional treatment process. In order to meet the regulatory standards and for safe disposal, it is necessary to go for tertiary treatment. Various tertiary treatment methods include adsorption, membrane separation process, ultra filtration, reverse osmosis etc. Adsorption has been found to be efficient for the removal of most of heavy metals in waste water at lower concentrations. Activated carbon is commonly used adsorbents, however, due to its high cost and loss in regeneration, various low cost adsorbents have been investigated during recent years.

The aim of the …