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Essential Characteristics

3) Duration of burning The incendiary materials must not only impart high temperatures but also maintain heat generation without replenishment of fuel. The heat must continue to radiate for an appreciable time and when the heated object is ready to bum, the fire must be present to ignite it. In fact two factors viz. intensity of heat and duration of burning are complementary to each other and must satisfy the purpose of incendiary materials. [Pg.374]

Desirable Characteristics In addition to essential characteristics, there are some desirable characteristics which are  [Pg.374]

1) An incendiary agent should be difficult to extinguish. However, this does not mean that an agent that resists extinguishment is always a better incendiary but it is desirable. For example, thermite that continues to burn even under water, is not satisfactory as a general purpose incendiary. [Pg.374]

2) Good heat radiating qualities are an asset to an incendiary agent, that is, the spread of luminosity for good distances greatly increases the probability of fire raising. [Pg.374]

3) The incendiary material should burn freely without exhausting too much oxygen from the air otherwise it will defeat its purpose as an incendiary. It must also burn completely without leaving a residue to insulate and thus prevent the surface on which it bums from catching fire. [Pg.375]


The density, distillation curve, viscosity, and behavior at low temperature make up the essential characteristics of diesei fuel necessary for satisfactory operation of the engine. [Pg.213]

This is the essential characteristic for every lubricant. The kinematic viscosity is most often measured by recording the time needed for the oil to flow down a calibrated capillary tube. The viscosity varies with the pressure but the influence of temperature is much greater it decreases rapidly with an increase in temperature and there is abundant literature concerning the equations and graphs relating these two parameters. One can cite in particular the ASTM D 341 standard. [Pg.282]

Process Chemistry. Manganese is combined with oxygen in its ores (see Table 3) and carbon is the most economical reducing agent for oxides. Therefore, the essential characteristics of manganese metallurgy is evident from examination of the interactions between manganese oxides and... [Pg.489]

Bosch and co-workers devised laboratory reactors to operate at high pressure and temperature in a recycle mode. These test reactors had the essential characteristics of potential industrial reactors and were used by Mittasch and co-workers to screen some 20,000 samples as candidate catalysts. The results led to the identification of an iron-containing mineral that is similar to today s industrial catalysts. The researchers recognized the need for porous catalytic materials and materials with more than one component, today identified as the support, the catalyticaHy active component, and the promoter. Today s technology for catalyst testing has become more efficient because much of the test equipment is automated, and the analysis of products and catalysts is much faster and more accurate. [Pg.161]

Inspection is also an important activity in the regulation of international trade through the certification of vehicles and containers used for transporting hazardous products and for providing foreign purchasers with evidence that manufactured goods comply with specification before they leave the country of origin. The essential characteristics of and requirements for an inspection authority are ... [Pg.142]

Although [3 3 3] profiles are more sensitive to system size than those for [2 2 2] rules, the essential characteristics of their general form appear to remain unchanged over the set of sizes sampled. [Pg.115]

Analysis proceeds from the assumption that in order to understand a system one must first break it up into its constituent parts. Understanding then comes from the knowledge gained by reconstructing the system. But for systems whose dynamics depend critically on interaction between pai ts, analysis often misses the essential characteristics of the whole system. Synthesis is the complementary act of putting the individual pieces together in order to understand what they do collectively. Understanding complex synthesis requires that both analysis and synthesis be done. [Pg.559]

An efficient LED has two essential characteristics (1) all of the injected carriers recombine in the device and (2) the operating voltage is as low as possible. To produce light efficiently, all of the current should lead to recombination. This... [Pg.190]

A decreased glycolytic rate has been proposed as a cause of muscle fatigue and related to pH inhibition of glycolytic enzymes. Decreasing pH inhibits both phosphorylase kinase and phosphofructokinase (PFK) activities. PFK is rate determining for glycolytic flux and therefore must be precisely matched to the rate of ATP expenditure. The essential characteristic of PFK control is allosteric inhibition by ATP. This inhibition is increased by H and PCr (Storey and Hochachka, 1974 ... [Pg.255]

One of the most accurate approaches to solve the LDF equations for the single slab geometry is the full-potential linearized augmented plane wave (FLAPW) method (10). Here, we highlight only the essential characteristics of this approach for further details the reader is referred to a recent review article (11). [Pg.52]

In summary, all the experiments expressly selected to check the theoretical description provided fairly clear evidence in favour of both the basic electronic model proposed for the BMPC photoisomerization (involving a TICT-like state) and the essential characteristics of the intramolecular S and S, potential surfaces as derived from CS INDO Cl calculations. Now, combining the results of the present investigation with those of previous studies [24,25] we are in a position to fix the following points about the mechanism and dynamics of BMPC excited-state relaxation l)photoexcitation (So-Si)of the stable (trans) form results in the formation of the 3-4 cis planar isomer, as well as recovery of the trans one, through a perpendicular CT-like S] minimum of intramolecular origin, 2) a small intramolecular barrier (1.-1.2 kcal mol ) is interposed between the secondary trans and the absolute perp minima, 3) the thermal back 3-4 cis trans isomerization requires travelling over a substantial intramolecular barrier (=18 kcal moM) at the perp conformation, 4) solvent polarity effects come into play primarily around the perp conformation, due to localization of the... [Pg.396]

Rules seemingly have the same format as IF.. THEN.. statements in any other conventional computer language. The major difference is that the latter statements are constructed to be executed sequentially and always in the same order, whereas expert system rules are meant as little independent pieces of knowledge. It is the task of the inference engine to recognize the applicable rules. This may be different in different situations. There is no preset order in which the rules must be executed. Clarity of the rule base is an essential characteristic because it must be possible to control and follow the system on reasoning errors. The structuring of rules into rule sets favours comprehensibility and allows a more efficient consultation of the system. Because of the natural resemblance to real expertise, rule-based expert systems are the most popular. Many of the earlier developed systems are pure rule-based systems. [Pg.632]

In comparing the two experiments with both slits open, we see that interacting with the system by placing a detector at slit A changes the wave function of the system and the experimental outcome. This feature is an essential characteristic of quantum theory. We also note that without a detector at slit A, there are two indistinguishable ways for the particle to reach the detection screen D and the two wave functions and are added together. [Pg.32]

The essential characteristic of a chain reaction mechanism is the existence of a closed cycle of reactions in which unstable or highly reactive intermediates react in propagation steps with stable reactant molecules or other intermediates and are regenerated by the sequence of reactions... [Pg.95]

Taxes. Taxis is a movement oriented with respect to the stimulus direction its essential characteristic, therefore, is active orientation of the organism with respect to the stimulus source. A taxis is not a response in the strict sense of the introductory definition, but rather the result of a response (or of a series of responses) of the motor apparatus. [Pg.52]

Polymers designed with this technique have a number of important aspects in common with proteins. First of all, the transition from a liquid-like globule into a frozen state occurs as a first order phase transition. Further, the frozen state itself has an essential stability margin, which is determined by the design parameters. As in real proteins, neither a large variation of temperature or other environmental conditions, nor a mutational substitution of several monomers leads to any change in basic state conformation. In this respect the ability of sequence design to capture certain essential characteristics of proteins seems quite plausible. [Pg.212]

J. N. Bronsted and T. M. Lowry independently arrived at definitions of an acid and a base that do not involve water. They recognized that the essential characteristic of an acid-base reaction was the transfer of a hydrogen ion (proton) from one species (the acid) to another (the base). According to these definitions, an acid is a proton donor and a base is a proton acceptor. The proton must be donated to some other species so there is no acid without a base. According to Arrhenius, HC1 is an acid because... [Pg.292]

Up to this point, we have dealt with the subject of acid-base chemistry in terms of proton transfer. If we seek to learn what it is that makes NH3 a base that can accept a proton, we find that it is because there is an unshared pair of electrons on the nitrogen atom where the proton can attach. Conversely, it is the fact that the hydrogen ion seeks a center of negative charge that makes it leave an acid such as HC1 and attach to the ammonia molecule. In other words, it is the presence of an unshared pair of electrons on the base that results in proton transfer. Sometimes known as the electronic theory of acids and bases, this shows that the essential characteristics of acids and bases do not always depend on the transfer of a proton. This approach to acid-base chemistry was first developed by G. N. Lewis in the 1920s. [Pg.305]

Within the solar system the observable changes are of a different kind, best described as chemical change. The most striking common feature of those chemical reactions driven by solar energy is their cyclic nature, linked to planetary motion. All phenomena, collectively known as life, or growth, are of this type. Their essential characteristic is a state far from equilibrium. For a life process, equilibrium is synonymous with death and chemical change after death is a rapid slide towards equilibrium. The most advanced chemical theories deal with these posthumous effects and related reactions only, albeit rather superficially. A fundamental theory to predict conditions for the onset of elementary chemical change is not available. [Pg.497]

The essential characteristic of the equilibrium correlations is that they originate in a system starting from non-correlated states. We recall also that the correct form of the equilibrium correlations can be obtained if one admits that for long times the velocity distribution function takes a Maxwellian form. [Pg.330]

In 1969, with recognition of environmental problems emerging, the resources of the University were put to work for the benefit of the state of California. Essential characteristics of what was needed to resolve environmental problems became apparent from work addressing California s critical concern air quality. These contrasted with basic research themes. [Pg.200]

Some satisfactory results were also obtained by modification of properties of phenol-formaldehyde resin (PFR) composites with the synthesized diallylsilazanes (scheme 1). Thas, addition of diallylsilazanes (1-3 mass %) to this composition has improved some of essential characteristics of hardened PFR (table 3). It should be noted that other important physical and mechanical properties of the composites have remained safe (table 3). [Pg.78]

The essential characteristic of dye lasers is their broad homogeneous gain profile. [Pg.59]

A significant cost advantage of alkaline fuel cells is that both anode and cathode reactions can be effectively catalyzed with nonprecious, relatively inexpensive metals. To date, most low cost catalyst development work has been directed towards Raney nickel powders for anodes and silver-based powders for cathodes. The essential characteristics of the catalyst structure are high electronic conductivity and stability (mechanical, chemical, and electrochemical). [Pg.98]


See other pages where Essential Characteristics is mentioned: [Pg.211]    [Pg.466]    [Pg.53]    [Pg.223]    [Pg.325]    [Pg.1097]    [Pg.43]    [Pg.213]    [Pg.5]    [Pg.524]    [Pg.226]    [Pg.170]    [Pg.458]    [Pg.260]    [Pg.104]    [Pg.175]    [Pg.322]    [Pg.133]    [Pg.266]    [Pg.4]    [Pg.33]    [Pg.85]    [Pg.222]    [Pg.311]    [Pg.319]    [Pg.217]    [Pg.11]   


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