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A direct

If any change in the conditions of a system in equilibrium causes the equilibrium to be displaced, the displacement will be in such a direction as to oppose the effect of the change. [Pg.35]

In general, heterogeneous catalysts are preferred to homogeneous catalysts because the separation and recycling of homogeneous catalysts often can be very difficult. Loss of homogeneous catalyst not only creates a direct expense through loss of material but also creates an environmental problem. [Pg.46]

Find a way to overcome the constraint while still maintaining the areas. This is often possible by using indirect heat transfer between the two areas. The simplest option is via the existing utility system. For example, rather than have a direct match between two streams, one can perhaps generate steam to be fed into the steam mains and the other use steam from the same mains. The utility system then acts as a buffer between the two areas. Another possibility might be to use a heat transfer medium such as a hot oil which circulates between the two streams being matched. To maintain operational independence, a standby heater and cooler supplied by utilities is needed in the hot oil circuit such that if either area is not operational, utilities could substitute heat recovery for short periods. [Pg.184]

Hall effect If a current (I) is passed through a conducting crystal in a direction perpendicular to that of an applied magnetic field (H), the conductor develops a potential (V) between the faces which are mutually perpendicular to both the direction of the current and the magnetic field. This is known as the Hall effect the magnitude of the potential difference is given by... [Pg.199]

With regards to the overall balance of combustion, the chemical structure of the motor or heating fuel, e.g., the number of carbon atoms in tbe chain and the nature of the bonding, does not play a direct role the only important item is the overall composition, that is, the contents of carbon, hydrogen, and — eventually— oxygen in the case of alcohols or ethers added to the fuel. [Pg.179]

Volatility is one of the most important properties of a hydrocarbon solvent. Volatility has a direct relation to the time it takes to evaporate the solvent and, therefore, to the drying time for the dissolved product. The desired value of volatility varies greatly with the nature of the dissolved product and its application temperature. Therefore, whether it be an ink that needs to dry at ambient temperature, sometimes very fast, or whether it be an extraction solvent, the volatility needs are not the same. [Pg.273]

The adaptive estimation of the pseudo-inverse parameters a n) consists of the blocks C and E (Fig. 1) if the transformed noise ( ) has unknown properties. Bloek C performes the restoration of the posterior PDD function w a,n) from the data a (n) + (n). It includes methods and algorithms for the PDD function restoration from empirical data [8] which are based on empirical averaging. Beeause the noise is assumed to be a stationary process with zero mean value and the image parameters are constant, the PDD function w(a,n) converges, at least, to the real distribution. The posterior PDD funetion is used to built a back loop to block B and as a direct input for the estimator E. For the given estimation criteria f(a,d) an optimal estimation a (n) can be found from the expression... [Pg.123]

In service inspections of French nuclear Pressure Water Reactor (PWR) vessels are carried out automatically in complete immersion from the inside by means of ultrasonic focused probes working in the pulse echo mode. Concern has been expressed about the capabilities of performing non destructive evaluation of the Outer Surface Defects (OSD), i.e. defects located in the vicinity of the outer surface of the inspected components. OSD are insonified by both a "direct" field that passes through the inner surface (water/steel) of the component containing the defect and a "secondary" field reflected from the outer surface. Consequently, the Bscan images, containing the signatures of such defects, are complicated and their interpretation is a difficult task. [Pg.171]

In contrast to a direct injection of dc or ac currents in the sample to be tested, the induction of eddy currents by an external excitation coil generates a locally limited current distribution. Since no electrical connection to the sample is required, eddy current NDE is easier to use from a practical point of view, however, the choice of the optimum measurement parameters, like e.g. the excitation frequency, is more critical. Furthermore, the calculation of the current flow in the sample from the measured field distribution tends to be more difficult than in case of a direct current injection. A homogenous field distribution produced by e.g. direct current injection or a sheet inducer [1] allows one to estimate more easily the defect geometry. However, for the detection of technically relevant cracks, these methods do not seem to be easily applicable and sensitive enough, especially in the case of deep lying and small cracks. [Pg.255]

By using modern high-performance computers, it has become possible to present the test data planiform. That way, for the first time a direct relation between the test signals and the test item could be achieved. [Pg.307]

A further advantage is the Selenium halflife of 120 days, which is 60% more when compared to iridium and a factor of approx. 4 when compared to Ytterbium. These differences turn out to be an important economical aspect when comparing the different sources, as they are a direct measure of the useful life of sources. The short halflife and the very high costs for Ytterbium sources have been the main factors for the rather low importance of Ytterbium in the full range of gamma radiography. [Pg.424]

Projection radiography is widely used for pipe inspection and corrosion monitoring. Film digitisation allows a direct access to the local density variations by computer software. Following to a calibration step an interactive estimation of local wall thickness change based on the obtained density variation is possible. The theoretical model is discussed, the limitations of the application range are shown and examples of the practical use are given. The accuracy of this method is compared to results from wall thickness measurements with ultrasonic devices. [Pg.561]

Projection radiography has long been used for pipe inspection and corrosion monitoring. In this traditional tangential wall thickness estimation the distance of border lines of the projected wall shadows of a pipe onto the film is a direct measure for the wall thickness. This method is not considered here, newer developments can be found in / /. [Pg.561]

The intial part of the pulse shapes are a direction of the minus as the incidence S45C side for the ultrasonic wave. [Pg.852]

While evidence for hydration forces date back to early work on clays [1], the understanding of these solvent-induced forces was revolutionized by Horn and Israelachvili using the modem surface force apparatus. Here, for the first time, one had a direct measurement of the oscillatory forces between crossed mica cylinders immersed in a solvent, octamethylcyclotetrasiloxane (OMCTS) [67]. [Pg.243]

A direct measurement of surface tension is sometimes possible from the work of cleaving a crystal. Mica, in particular, has such a well-defined cleavage plane that it can be split into large sheets of fractional millimeter thickness. Orowan... [Pg.278]

Thus, adding surfactants to minimize the oil-water and solid-water interfacial tensions causes removal to become spontaneous. On the other hand, a mere decrease in the surface tension of the water-air interface, as evidenced, say, by foam formation, is not a direct indication that the surfactant will function well as a detergent. The decrease in yow or ysw implies, through the Gibb s equation (see Section III-5) adsorption of detergent. [Pg.485]

A second general type of procedure, due to McBain [29], is to determine n by a direct weighing of the amount of adsorption. McBain used a delicte quartz spiral spring, but modem equipment generally makes use of a microbalance or a transducer. An illustrative schematic is shown in Fig. XVII-6. [Pg.616]

N2 as adsorbate, was quite similar to that for N2 on a directly prepared and probably amorphous ice powder [35, 141], On the other hand, N2 adsorption on carbon with increasing thickness of preadsorbed methanol decreased steadily—no limiting isotherm was reached [139]. [Pg.655]

We have alluded to the comrection between the molecular PES and the spectroscopic Hamiltonian. These are two very different representations of the molecular Hamiltonian, yet both are supposed to describe the same molecular dynamics. Furthemrore, the PES often is obtained via ab initio quairtum mechanical calculations while the spectroscopic Hamiltonian is most often obtained by an empirical fit to an experimental spectrum. Is there a direct link between these two seemingly very different ways of apprehending the molecular Hamiltonian and dynamics And if so, how consistent are these two distinct ways of viewing the molecule ... [Pg.72]


See other pages where A direct is mentioned: [Pg.265]    [Pg.291]    [Pg.294]    [Pg.86]    [Pg.155]    [Pg.163]    [Pg.174]    [Pg.232]    [Pg.289]    [Pg.381]    [Pg.390]    [Pg.434]    [Pg.219]    [Pg.46]    [Pg.155]    [Pg.231]    [Pg.249]    [Pg.250]    [Pg.270]    [Pg.488]    [Pg.541]    [Pg.845]    [Pg.854]    [Pg.868]    [Pg.882]    [Pg.885]    [Pg.198]    [Pg.370]    [Pg.602]    [Pg.655]    [Pg.113]   
See also in sourсe #XX -- [ Pg.761 ]




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A Derivation of Steepest Descent Direction

A Direct-Current Circuits and Measurements

A New Policy Direction in Australian Offshore Safety Regulation

A Procedure for Finding Every Direct Mechanism

A Scalar Direct MP2 Algorithm

A Transition probabilities along the z direction

A direct photolysis

A method for sequencing single stranded cloned DNA in both directions by the dideoxynucleotide-chain termination procedure

A permanent (direct) electric current

A-directing influence

Aromatic substitution, a quantitative treatment of directive effects

Can a Reaction Be Catalyzed in Both Directions

Chloroorganosilanes from a Direct Process

Control of the pretilt direction by a hybrid cell

Determining the Directing Effects of a Substituent

Diffusivity as a Function of Direction

Direct Calibration for a Synchrotron Beamline

Direct Dyes with a Urea Bridge

Direct Identification of a Closed-Loop Process

Direct Titration Curve of a Metallic Ion with EDTA

Direct Titrations of Derivatives Exhibiting a Basic Character

Direct Use of Synthetic Polymers as Drugs and Therapeutic Agents

Direct a-Chlorination of Aldehydes and Ketones

Direct a-Fluorination of Aldehydes

Direct a-Oxygenation Reactions of Aldehydes and Ketones

Direct a-Selenation of Aldehydes and Ketones

Direct a-Sulfenylation of Aldehydes

Direct a-amination

Direct isotope dilution analysis with a radioactive

Direct observation of a repulsion between polymer chains in dilute solutions

Directed Evolution as a Means to Engineer Enantioselective Enzymes

Directing 3D Topological Defects in Smectic Liquid Crystals and Their Applications as an Emerging Class of Building Blocks

Direction in a crystal

Direction of a Vector

Directional Flow for Helix Rotation with a Stationary Screw Core and Barrel

Directive effects in aromatic substitution, a quantitative treatment

Distortions due to Direct Interaction of a Field with the Director

Electrochemical Aptasensors Based on a Direct Assay

FCC catalyst deactivation a review and directions for further research

Future Directions - Establishing a Novel Chemistry by Enabling Function

Future Directions in Natural Products as Drugs and Drug Design Templates

Journey to a Safety Culture Determining the Direction of Your Management System

Macondo and the Possibility of a New European Directive

Metal-Directed Rearrangement to Produce a More Suitable Cavity

Molecular Devices with Directional Functionality Supermolecules that Transmit Signals in a Desired Direction

Molecular systems using a direct geometry spectrometer

Molten Salt Electrochemical Processes Directed Toward a Low Carbon Society

Polarizability as a Directional Property

Predicting the Direction of a Reaction

Reactions of Ketones Containing a Directing Group

Reactions of Ketones Using a Temporary Directing Group

Skill 11.1c-Diagram the direction of heat flow in a system

Spray Towers as Direct Contact Condensers

Stopped Flow Kinetic Analysis A Direct Assay for Superoxide Dismutase Activity

The direction of vapour transport across a thermal gradient

The flagellar motor has a default direction of rotation, counterclockwise

To conclude a summary of equilibrium and directed aldol methods

Transition Metals as Protecting, Activating, and Directing Groups

Two Identical Sites on a Polymer Direct Interaction between the Ligands

Use of Poly (Dimethyl Ketone) to Manufacture Articles in Direct Contact with a Humid or Aqueous Medium

Use of glycals as direct glycosyl donors haloglycosylation

Which gives preparative directions for substances formed either as principal products

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