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This book contains a series of engaging activities that offer students a chance to explore acids and bases using the special indicator properties of red cabbage juice. The activities allow students to discover acids and bases through their own experiments and interpretations. The skills of observing, recording results, comparing, classifying, experimenting, and drawing conclusions are promoted, and the concepts of acid, base, neutral, indicators, pigments, safety, neutralize, and concentration are also covered. The important themes are systems and interactions, stability, patterns of change, scale, and matter. Summary outlines, extensions, assessment suggestions, literature connections, and data sheets are also included. (JRH)

Background information on natural polymers, synthetic polymers, and the properties of polymers is presented as an introduction to this curriculum guide. Details are provided on the use of polymer products in consumer goods, polymer recycling, polymer densities, the making of a polymer such as GLUEP, polyvinyl alcohol, dissolving plastics, polymers and polarized light, "skewering a balloon", and making a "super slurper." Background information is linked to hands on activities and teacher guide notes are provided. (DDR)

Intended to be a source of information on the nature and significance of health effects related to chemical disposal, this document is the final report of the Executive Scientific Panel on Health Aspects of the Disposal of Waste Chemicals. The panel, which was organized by the Universities Associated for Research and Education in Pathology (UAREP), reviewed scientific literature, commissioned reports from various task forces on waste disposal, and solicited input from scientists and interested individuals and organizations. Findings are reported on: (1) waste chemicals of major concern; (2) factors influencing human exposure; (3) the assessment of health effects; (4) epidemiology in exposed populations; (5) factors involved in risk assessment; (6) chemical exposure health studies; (7) disposal site health studies; and (8) international aspects of chemical waste disposal. The report is summarized, and conclusions and recommendations are included. The appendices contain a synopsis of information on various chemicals, a list of study participants, and a list of individuals and organizations responding to the draft report. (TW)

This chapter introduces the chemical reaction algorithm; it describes the main characteristics and definitions. In this work, the main objective is to introduce a novel optimization algorithm based in a paradigm inspired by nature, the chemical reactions. [ABSTRACT FROM AUTHOR]

This chapter introduces the chemical reaction algorithm; it describes the main characteristics and definitions. In this work, the main objective is to introduce a novel optimization algorithm based in a paradigm inspired by nature, the chemical reactions. [ABSTRACT FROM AUTHOR]

This chapter describes the theoretical concepts and background required to understand the new nature inspired optimization method based on the paradigm of chemical reactions. [ABSTRACT FROM AUTHOR]

In this chapter, the mathematical description of spray processes is presented. After a brief summary of the basic mathematical concepts used, a discussion of the conservation equations is given, followed by a brief introduction to turbulence. Subsequently, a discussion of turbulence modeling is presented including Reynolds-averaged Navier–Stokes (RANS) and large eddy simulation (LES) modeling. Once this basic background is established, the discussion of the averaged or filtered conservation equations in conjunction with the liquid phase equations is given. The chapter ends with a discussion of the discretization of the equation system and the main algorithms used for the numerical solutions. [ABSTRACT FROM AUTHOR]

The classification regimes for premixed and non-premixed combustion processes are discussed in terms of the Damköhler and Karlovitz numbers. Dec΄s diesel spray combustion concept is introduced, followed by a short review of chemical kinetics. The ignition process together with appropriate models is then discussed. Subsequently, various combustion models are presented, including mixing-controlled, flamelet and PDF combustion models. The chapter ends with a discussion of pollutant modeling for nitric oxides (NO) and particulates. [ABSTRACT FROM AUTHOR]

The viscous fingering of miscible flow displacements in a homogeneous porous media is examined in the case involving non-autocatalytic chemical reactions between the fluids. The problem is formulated using continuity equation, Darcy's law, and volume-averaged forms of convection-diffusion-reaction equation for mass balance. Full nonlinear simulations using a pseudo-spectral method, allowed to analyze the mechanisms of fingering instability that result from the dependence of the fluids viscosities on the concentrations of the different species. In particular, the study examined the effects of varying important parameters namely the Damkohler number that represents the ratio of the hydrodynamic and chemical characteristic time scales, and the Peclet number that accounts for the inertial versus diffusive effects. [ABSTRACT FROM AUTHOR]

This work studies the dynamic behavior of process networks consisting of a hard chrome electroplating bath connected with a heat exchanger, which is immersed in the electroplating bath and connected with a cooling system. The heat exchanger is used to remove the heat produced from high current load in the electroplating process as well as to maintain the temperature of the bath at a properly specified range of between 45 and 50°C. However, in most cases, the temperature of the plating solution cannot be kept at the range due to the fact that the heat exchanger cannot sufficiently remove the heat released from chemical reactions in the electroplating bath. As a result, a new design heat exchanger regarding its shape is developed. It was found that with the new design heat exchanger, the temperature of the bath can be maintained at the range throughout the process. In addition, to study the dynamic behavior of the bath, its mathematical models have been developed and unknown parameters have been estimated based on actual plant data. Simulation results have shown that the developed models give good prediction of the bath's solution temperature. [ABSTRACT FROM AUTHOR]

Chapter 5 of the book "Physical Science: Microworlds: Unlocking the Secrets of Atoms and Molecules," by Anna Claybourne is presented. It deals with the bonding and reacting of atoms. It explains how do atoms bond together and why they bond. It discusses the covalent bonding, ionic bonding, and chemical reaction.

Chapter one of the book "Enjoy Your Meal: What Happens to Your Food When You Eat?" by Emily McGregor is presented. It explores the process of food digestion and its characteristics. It highlights the function of enzymes, which break down different types of food. It emphasizes the process of using the broken down food.

The article focuses on the use of mechanical decontamination for surface or sub-surface decontamination. Various mechanical decontamination techniques are stated which include flushing with water, Vacuuming/Wiping/Scrubbing, and Strippable Coatings. A chart is presented depicting mechanical decontamination techniques and their applications.

Supercritical (SC) CO2 and ionic liquids (ILs) are two types of solvents with special properties, which have been used as reaction media for different chemical reactions. In this chapter, some recent work about the effect of phase behavior on chemical reactions in SC CO2 and SC CO2/IL biphasic systems are discussed. [ABSTRACT FROM AUTHOR]

PolysaccharidesPolysaccharides occurence arePolysaccharides properties presentPolysaccharides significance in all living organisms where they carry out one or more of their diverse functions. While there is no specific category or definition of a complex polysaccharide, most are structurally complex. Polysaccharides contain 1–5 different monosaccharide (sugar) units. The different sugar units may have different anomeric configurations and/or be joined by different glycosidic linkages. Polysaccharides may be linear or branched. Branches may be short saccharide units on a linear backbone or the molecule may have a branch-on-branch structure; in either case, the branches may be isolated or clustered. Polysaccharides may contain non–carbohydrate groups. Esters or cyclic acetal groups, when present, can be removed by appropriate treatments. All polysaccharides are polydisperse, i. e., are present in a range of molecular weights rather than having a single molecular weight. Most are polymolecular, i. e., differ in fine structure from molecule to molecule. So most polysaccharides can be said to be structurally complex. They may be attached to protein molecules or to other polysaccharide molecules. They are solvated by water. Most dissolve in aqueous systems, especially if they are alkaline. Polysaccharides can be depolymerized by acids and heat, specific enzymes, and high pH systems following oxidation. Their hydroxyl groups can be esterified (acylated), etherified (alkylated), and oxidized. Amino groups can be acylated (and deacylated). Carboxyl groups can be converted into esters, amides, and amines. Structural modification makes the molecules even more complex and polymolecular and, perhaps, polydisperse. [ABSTRACT FROM AUTHOR]

Keep up your bright swords, for the dew will rust them. Water is the most common substance on Earth, and it no doubt has the best known of all chemical formulas: H2O. It is one of only two liquids that occur naturally in appreciable quantities, the other example being petroleum. More than three quarters of the Earth's surface is covered with water, and if it were not for this compound, there would be no life. About 60% of the weight of the human body is water, it being present in the interior of every cell. It also accounts for the bulk of such specialized aqueous media as blood and mucous. The central role played by water was of course clear from the earliest times, and Aristotle regarded it as one of the four elements, together with air, fire and earth. Its chemical structure became clear in the late eighteenth century, when Henry Cavendish and Antoine Lavoisier established that it is a combination of hydrogen (discovered by Cavendish in 1766) and oxygen (discovered by Joseph Priestley in 1774). Cavendish burned measured quantities of these two gases together and found that they produced water, no change in total weight having occurred during the reaction. The reverse process, decomposition of water into hydrogen and oxygen, was first achieved by Lavoisier. In spite of its abundance and apparent simplicity, water is an unusual compound, and compared with other liquids we could call it exotic. [ABSTRACT FROM AUTHOR]

All things began in order, so shall they end, and so shall they begin again; according to the ordainer of order and mystical mathematics of the city of heaven. Until now, our discussion has concerned isolated atoms and clusters of very few atoms. Considering that a single cubic centimetre of a typical piece of condensed matter, a block of stainless steel for example, contains approximately 1023 atoms, we see that there is still a long way to go in the description of actual substances. We must now inquire how large numbers of atoms are arranged with respect to one another, so as to produce the great variety of known materials. It will transpire that the observed arrangements are dictated both by the forces between atoms and the prevailing physical conditions. Before going into such details, however, it will be useful to examine the simple geometrical aspects of the question. It is frequently adequate to regard atoms as being spherical. The two-dimensional equivalent of a sphere is a circle, so we can begin by considering the arrangement of circles on a piece of paper. The circles could be drawn at random positions, well spread out and with close encounters occurring only by occasional chance. This is a reasonable representation of the instantaneous situation in a simple monatomic gas. A variant of this drawing would replace the single circles by small groups of circles, and we would then have a molecular gas. [ABSTRACT FROM AUTHOR]

I can trace my ancestry back to a protoplasmal primordial atomic globule. Consequently, my family pride is something inconceivable. I can't help it. I was born sneering. Our world is a material world. Everything we see, touch, taste or smell is composed of one or more materials. Even our hearing depends on the interaction of the eardrums with the gaseous form of that familiar, though invisible, material known as air. Interest in the matter that makes up our environment has grown with the realization that it can be brought under control. At the dawn of civilization this control was of a rather rudimentary type. The earliest use of such materials as stone, wood, and the bones and skin of animals involved relatively minor alterations to these substances, and they were naturally taken for granted. Just which physical phenomena led to speculation about the nature of materials remains a matter of conjecture. The stimulation probably came from observations of simple modifications of state, such as the irreversible change caused by the burning of wood and the reversible changes between the solid, liquid, and gaseous forms of substances like water. The great diversity of form and behaviour seen in the material world stems from the wide range of chemical composition. Although chalk and cheese, for example, are both composed of atoms, the atoms are of different kinds and are combined in different ways. [ABSTRACT FROM AUTHOR]

The force of nature could no farther go; to make a third she join'd the former two. Most substances are mixtures of two or more elements, and chemical compounds are found to have definite compositions. They are also found to consist of molecules, which are the smallest particles that can exist in the free state and still retain the characteristics of the substance. Thus the chemical formula for water is always H2O, indicating that its molecules contain two hydrogen atoms and one oxygen. (The subscript 1 is not written explicitly; H2O implies H2O1.) The formula H2O2, in which the relative proportions of hydrogen and oxygen are different from those in water, belongs to a different chemical compound, the common bleaching agent hydrogen peroxide. Similarly, sodium chloride, also known as common salt, has the formula NaCl, and not Na2Cl or NaCl3. This shows that the forces that hold atoms together in groups must have certain characteristics which determine the rules of combination. The occurrence of chemical reactions reveals that the forces can be overcome, allowing the atoms to move apart and establish bonds with other atoms. A simple example of such an event is the reaction Zn + 2HCl → ZnCl2 + H2 in which the addition of hydrochloric acid to zinc produces zinc chloride and hydrogen, which is liberated as a gas. This demonstrates that the binding forces between zinc and chlorine atoms are stronger than those which hold hydrogen to chlorine. [ABSTRACT FROM AUTHOR]

Major advances in transition-metal catalyzed reactions have taken place since the discovery of N-heterocyclic carbenes (NHCs). This review provides a summery of recent M-NHC catalyzed reactions including cycloadditions, rearrangements, coupling reactions, polymerizations, and the additions of H-X. [ABSTRACT FROM AUTHOR]

Chapter 5 of the book "2006 American Society of Heating, Refrigeration and Air-Conditioning Engineers Handbook (ASHRAE)-Refrigeration" is presented. It explores the chemical aspects of both historical and new refrigerants and refrigerant blends to design a long-lasting and reliable refrigeration system. It also highlights chemical reactions, compatibility of materials and chemical evaluation techniques.

#x003BA;B-Ras1 and #x003BA;B-Ras2 are two small proteins that display similarity at the amino acid level to Ras-like small GTPases. Although little is known about the function of the #x003BA;B-Ras proteins, they have been shown to interfere with activation of transcription factor NF-#x003BA;B. They accomplish this by binding to I#x003BA;B proteins, natural inhibitors of NF-#x003BA;B, and delaying their stimulus-dependent degradation. In this chapter, we consider the #x003BA;B-Ras proteins in light of their NF-#x003BA;B regulatory properties. Three fundamental questions about #x003BA;B-Ras function are addressed: 1) Does #x003BA;B-Ras regulate NF-#x003BA;B in vivo? 2) Does #x003BA;B-Ras selectively regulate specific NF-#x003BA;B/I#x003BA;B complexes? 3) Does #x003BA;B-Ras function as a true GTPase, that is, with molecular switching properties that correlate with the phosphorylation state of bound guanine nucleotide? Finally, we detail the methods currently used to study the #x003BA;B-Ras proteins as regulators of NF-#x003BA;B activation [ABSTRACT FROM AUTHOR]

The Raf/MEK/ERK protein kinases constitute a key effector cascade used by Ras to relay signals regulating cell growth, survival, proliferation, and differentiation. These kinases are activated in a sequential manner through direct phosphorylation. Raf is the initiating kinase that interacts with membrane-localized GTP-bound Ras. The signal is then transduced from Raf to MEK and from MEK to ERK, ultimately resulting in the phosphorylation of critical cellular targets by activated ERK. In addition to the core enzymes of the cascade, various scaffolding proteins and signaling modulators have been identified that affect the efficiency and level of signaling through this important kinase cascade. An emerging concept is that these factors contribute to the spatiotemporal control of Ras/ERK signaling, allowing sensitive activation and deactivation of the pathway in response to diverse extracellular cues [ABSTRACT FROM AUTHOR]

Phospho-specific antibodies have become very useful reagents for study of signal transduction pathways. This chapter describes the production of phospho-specific antibodies and their use to assess individual phosphorylation events in vivo in cells. The first step involves the synthesis of peptides (12-15 residues), where the phosphorylation site is centrally located, and a cysteine residue is incorporated at either the N- or C-terminus of the peptide to facilitate coupling it to an immunogenic carrier protein. No special immunization protocols are required to generate phospho-specific antibodies. Typically, animals of choice are immunized twice, several weeks apart, and enzyme-linked immunosorbent assay is used to determine the relative titer of sera against phosphorylated and nonphosphorylated peptides. Where the titer against phosphorylated peptides is much greater than nonphosphorylated peptides, the sera can be used at appropriate dilutions without further processing. In case a significant level of antibodies specific to the nonphosphorylated peptide is present in the antisera, an enhancement step is used to obtain a useful phospho-specific antibody. Although these enhanced antisera are suitable for many applications, there may be circumstances where affinity-purified antibodies are required. These antibodies can be used to detect a particular phosphorylation event in vivo using Western blotting, immunoprecipitation, and immunofluorescence. [ABSTRACT FROM AUTHOR]

A silver/alumina catalyst was tested for its NOX reduction activity during oxygen-rich conditions and during variation in the input parameters (nitric oxide, octane and oxygen). A multi-bed approach was tested where the initial bed was divided into four beds acting in different temperature rages. The experimental data were investigated by means of artificial neural networks that were demonstrated to be able to model the process. [ABSTRACT FROM AUTHOR]

In chemical reactions the additive constants in the internal energies and entropies of the constituents play a significant role. To be sure, it is not the constants themselves that matter but certain combinations, which we may call the heat of reaction and the entropy of reaction. These values can be determined experimentally and have been tabulated. The balance of the heat of reaction and the entropy of reaction goes a long way in determining whether a reaction can proceed and in which direction it proceeds. We give some examples: Dissociation of oxygen, ammonia synthesis and photosynthesis of glucose. The latter appears to be impossible, if we did not know better. [ABSTRACT FROM AUTHOR]

Boundary films are formed by physisorption, chemisorption, and chemical reaction. With physisorption, no exchange of electrons takes place between the molecules of the adsorbate and those of the adsorbant. The physisorption process typically involves van der Waals forces, which are relatively weak. In chemisorption, there is an actual sharing of electrons or electron interchange between the chemisorbed species and the solid surface. The solid surfaces bond very strongly to the adsorption species through covalent bonds. Chemically reacted films are formed by the chemical reaction of a solid surface with the environment. The physisorbed film can be either monomolecularly or polymolecularly thick. The chemisorbed films are monomolecular, but stoichiometric films formed by chemical reaction can have a large film thickness. In general, the stability and durability of surface films decrease in the following order: chemically reacted films, chemisorbed films, and physisorbed films. A good boundary lubricant should have a high degree of interaction between its molecules and the sliding surface. As a general rule, liquids are good lubricants when they are polar and, thus, able togrip solid surfaces (or be adsorbed). In this chapter, we focus on PFPEs. We first introduce details of the commonly used PFPE lubricants; then present a summary of nanodeformation, molecular conformation, and lubricant spreading studies; followed by an overview of nanotribological properties of polar and nonpolar PFPEs studied by atomic force microscopy (AFM) and some concluding remarks. [ABSTRACT FROM AUTHOR]

An encyclopedia entry for the term "ubiquitin-related modifiers" is presented. These modifiers are proteins, like NEDD8/RUB, that are structurally related to ubiquitin and post-translationally attached to other proteins. Interferon-induced UCRP, the first modifier described, is the result of the cross-reaction with anti-ubiquitin antibodies.

An encyclopedia entry for the term "Mitogen activated protein kinase cascades," is presented. It refers to three kinase modules activated by phosphorylation. The cascade has multiple members that are conserved from yeast to human. It was also defined as signaling module that serve as significant mediators of signal transduction from the cell surface to the nucleus.