Direction indices

Keywords d rec methods, indirect methods, rock properties, coring, core barrel, standard core analysis, special core analysis, slabbed core, sidewall samples, direct indications, microfossils, sonde, logging unit, invasion, mudcake, formation pressure measurement, fluid sampling, measurement while drilling, formation evaluation while drilling. 

SWS are useful to obtain direct indications of hydrocarbons (under UV light) and to differentiate between oil and gas. The technique is applied extensively to sample microfossils and pollen for stratigraphic analysis (age dating, correlation, depositional environment). Qualitative inspection of porosity is possible, but very often the sampling process results in a severe crushing of the sample thus obscuring the true porosity and permeability. 

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. 

The reaction proceeds in the direction indicated because a C—F bond is much stronger than a C—Br bond... 

Recoveries and separation factors are useful ways to evaluate the effectiveness of a separation. They do not, however, give a direct indication of the relative error introduced by failing to remove all interferents or failing to recover all the analyte. The relative error introduced by the separation, E, is defined as... 

Km for an enzymatic reaction are of significant interest in the study of cellular chemistry. From equation 13.19 we see that Vmax provides a means for determining the rate constant 2- For enzymes that follow the mechanism shown in reaction 13.15, 2 is equivalent to the enzyme s turnover number, kcat- The turnover number is the maximum number of substrate molecules converted to product by a single active site on the enzyme, per unit time. Thus, the turnover number provides a direct indication of the catalytic efficiency of an enzyme s active site. The Michaelis constant, Km, is significant because it provides an estimate of the substrate s intracellular concentration. 

Provide wind direction indication visible from inside the building / control room... 

Fig. 5.6. Direction indices for identifying crystal directions, showing how the [166] direction is defined. The lower part of the figure shows the family of (111 > directions.

Where stray currents are involved, several measurements have to be taken that are continually changing with time, simultaneously with each other. A double recorder is most suitable for this. Linear recorders with direct indication of the measurements cannot be used for potential measurements because the torque of the mechanism is too small to overcome the friction of the pen on the paper. Amplified recorders or potentiometer recorders are used to record potentials. In amplified recorders, as in amplified voltmeters, the measured signal is converted into a load-independent impressed current and transmitted to the measuring mechanism, which consists of a torque motor with a preamplifier. The amplifier results in an... 

Table 10.18(c) Direct-indicating Drager diffusion tubes - no pump required... 

The literature also contains other less quantitative but direct indications of the importance acid-base effects in contact adhesion [35,78,103]. 

Wlien there are unwanted incidental releases of highly hazardous chemicals in the process area, the employer must inform employees of the actions/procedures to take. If the employer wants employees to evacuate the area, then the emergency action plan will be activated. Eor outdoor processes, where wind direction is important for selecting the safe route to a refuge area, the employers should place a wind direction indicator, such as a wind sock or pennant, at the highest point visible... 

The inelastic wave shows rise times that vary quite substantially. Recognizing that the rise time is a direct indication of the balance between the viscous response of the sample and the driving force, Grady [81G01] has analyzed and compared the effective viscosity of a range of materials. These viscosities are manifestations of the dynamic deformation controlled by the shock-induced defects, heterogeneities, and their motions. 

Normal mode analysis provides a good example of information which is obtainable only through a theoretical calculation, since spectroscopic data does not directly indicate the specific type of nuclear motion producing each peak. Note that it is also possible to animate vibrational modes in some graphics packages. 

Hinweis, m. hint reference, indication, hinweisen, v.t. refer, direct, indicate. — v.i. point (to). 

Direct Indicating Viscometer. This is a rotational type instrument powered by an electric motor or by a hand crank. Mud is contained in the annular space between two cylinders. The outer cylinder or rotor sleeve is driven at a constant rotational velocity its rotation in the mud produces a torque on the inner cylinder or bob. A torsion spring restrains the movement. A dial attached to the bob indicates its displacement. Instrument constants have been so adjusted that plastic viscosity, apparent viscosity, and yield point are obtained by using readings from rotor sleeve speeds of 300 and 600 rpm. 

Figure 4-107. Typical flow curve of mud using a direct-indicating viscometer.

Plastic Viscosity and Yield Point. Plastic viscosity and yield point measurements are obtained from a direct indicating viscometer. Due to the temperature effect on the flow properties of oil-base mud, the testing procedure is modified. The mud sample in the container is placed into a cup heater [23]. The heated viscometer cup provides flow property data under atmospheric pressure and bottomhole temperature. 

Gel Strength. The gel strength of oil-base muds is measured with a direct indicating viscometer exactly like that of water-base muds. 

The systems that use dynamic alert/alarm limits base their logic on the rate of change of vibration amplitude. Any change in the vibration amplitude is a direct indication that there is a corresponding change in the machine s mechanical condition. However, there should be a maximum acceptable limit, i.e. absolute fault. 

Fig. 1.20 Cell consisting of two reversible Ag /Ag electrodes (Ag in AgN03 solution). The rate and direction of charge transfer is indicated by the length and arrow-head as follows gain of electrons by Ag -he- Ag—> loss of electrons by Ag - Ag + e- —. (o) Both electrodes at equilibrium and (f>) electrodes polarised by an external source of e.m.f. the position of the electrodes in the vertical direction indicates the potential change. (K, high-impedance voltmeter A, ammeter R, variable resistance)...

By the use of suitable shunts, the basic moving-coil movement can be adapted to measure m almost unlimited range of currents. Figure 10.46 illustrates a direct-indicating instrument with shunt, to measure current up to 5 A d.c. To ensure that the resistance of the circuit is not materially altered by the insertion of an ammeter, it is usual to install either a shunt or the meter itself (usually a moving-coil meter with internal shunt) permanently in the circuit. Ammeter shunts are normally of the four-terminal type, to avoid contact resistance errors, i.e. two current terminals and two potential terminals, as shown, in fig. J0.46. 

The oil in a refrigeration system should remain as clean as it is when it enters the compressor (unlike that of the automobile engine which is quickly contaminated by fuel, water, carbon and atmospheric dust). The condition of the compressor oil is therefore a direct indication of the physical and chemical cleanliness of the system. 

Finally, one more phenomenon is connected with the dependence of swelling on pressure. It is quite clear that the soil layer exerts certain pressure on the SAH particles and this pressure depends on the depth. This factor additively reduces SAH efficiency as a water absorbent. We possess some data, yet unpublished, which directly indicate some decrease of the SAH swelling in soils with the depth of their residence. 

Fig. 3-14. An RC Filter Whose Input is a Current with Reference Direction Indicated by the Arrow, and Whose Output is a Voltage with Reference Polarity as Shown.

Oae and coworkers oxidized several diaryl, dialkyl and alkyl aryl sulfides to their corresponding sulfoxides using purified cytochrome P-450 obtained from rabbit liver microsomes138. In agreement with expectations, this enzyme did not exhibit much stereospecificity. Some examples including the observed e.e. values are shown by 121-125. A model was proposed to account for the absolute configurations of the sulfoxides produced (126). The sulfur atom is preferentially oxidized from the direction indicated. 

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