Tools sonic

The sonic tool measures the time taken for a sound wave to pass through the formation. Sound waves travel in high density (i.e. low porosity) formation faster than in low density (high porosity) formation. The porosity can be determined by measuring the transit time for the sound wave to travel between a transmitter and receiver, provided the rock matrix and fluid are known. 

A problem with the early MWD mud pulse systems was the very slow rate of data transmission. Several minutes were needed to transmit one set of directional data. Anadrill working with a Mobil patent [100] developed in the early 1980s a continuous wave system with a much faster data rate. It became possible to transmit many more drilling data, and also to transmit logging data making LWD possible. Today, as many as 16 parameters can be transmitted in 16 s. The dream of the early pioneers has been more than fulfilled since azimuth, inclination, tool face, downhole weight-on-bit, downhole torque, shocks, caliper, resistivity, gamma ray, neutron, density, Pe, sonic and more can be transmitted in realtime to the rig floor and the main office. 

A successful sonic-while-drilling tool must overcome four major problems ... 

Figure 4-291. Schematic of the LWD sonic tool. (Courtesy SPWLA [116].J...

The -sonic log can also be used to detect overpressured zones. The sonic measurements until recently were available only on wireline. Now, MWD sonic tools have been developed adding one more parameter for overpressure detection while drilling. Two equations relating the formation porosity to the transit time are used ... 

Maximum disruption is obtained in a zone close to the probe tip and the biological cells must be kept here for sufficient time to allow disruption to take place. A delicate balance must therefore be struck between the power of the probe and the disruption rate since power ultrasound, with its associated cavitational collapse energy and bulk heating effect, can denature the contents of the cell once released. Indeed for this type of usage it is important to keep the cell sample cool during sonication. The method is very effective and continues to be an important tool in microbiology and biochemistry research. 

Example of commonest precise gradation of grinding tools with Grindo-Sonic (after Moser, 1980)... 

Tools for the preparation of a crude cell extract. A Hand-operated homogenizers, courtesy of Ace Glass, Inc., Vineland, NJ B Homogenizer with electric motor, courtesy of VWR Scientific, Division of Univar. C Sonicator, courtesy of Curtin Matheson Scientific, Inc... 

Sonication is a tool for improvement of chemical processes such as photocatalytic reaction. The improvements of reaction rates, yields and selectivity, the generation of reactive intermediate species and so on were reviewed.36) Some examples have been also shown in this chapter. The development of a new reaction pass by the combined effect of photocatalysis and sonolysis is expected in the near future. The contribution to Green Chemistry is one of typical examples. 

Gardner, J. S., Harrison, R. G., Lamb, J. D., Dearden, D. V., Sonic spray ionization mass spectrometry a powerful tool used to characterize fragile metal-assembled cages. New]. Chem. 2006, 30, 1276-1281. 

Ultrasonic machining, also known as ultrasonic impact grinding, uses ultra-sonically induced vibration delivered to a tool to create accurate cavities and channels of many shapes [146]. It can be used to form deep cavities as small as 250 pm in diameter (with an accuracy of 50 pm) in both hard and brittle materials such as glass, quartz, polymers, ceramics and metals. This technique may be useful for fabrication of large masters. 

As mentioned above, an important factor that controls the performance and especially the electrical properties of CNTs-reinforced composites is the state of dispersion of CNTs. Ultrasonication has been shown to be more effective in dispersing the nanotubes without the need for surfactants or other chemical treatments. Figure 12.5b presents electrical results of samples prepared by using a different composite processing. MWNTS were dispersed in this case in cyclohexane by ultrasonication and the MWNTs suspension was then mixed into a cyclohexane solution of SBR. Mixing was achieved by a further sonication for 30 minutes. Cyclohexane has been chosen in this case on account of the solubility of the rubbers in this solvent. As revealed in Figure 12.5b, the percolation threshold is shifted to a lower nanotube content and from this point of view, measurements of electrical resistivity appears as an indirect tool to evaluate the state of dispersion. 

The more common emulsion formed in the petroleum industry is the water-in-oil type. The sensitivity of electrokinetic sonic analysis to coagulation-coalescence processes in water-in-oil media is of great importance. It allows for rapid selection and optimization of different chemical demulsifiers. In addition, as a research tool, it supports the development of a fundamental understanding of chemical treatment of water-in-oil emulsions. 

Sonic transit time, neutron density and density log data for the cored interval are presented as functions of depth in Fig. 5. The same data are cross-plotted in Fig. 6 with the positions of the three minerals added. Equations (l)-(4) can be solved for porosity plus three solid-grain components. The logs have been converted into fractional porosity and the fractional quantities of quartz, dolomite and shale. The rock was thus assumed to consist of three minerals quartz (all silica minerals and feldspar), dolomite (all carbonate minerals) and shale (all clay minerals). Each group of minerals has approximately uniform responses to the three wireline logging tools. Petrographic analysis shows that the quartz/feldspar ratio is greater than about three (Table 3), suggesting that the assumption about the quartz component is... 

Liposomes have become known as one of the most versatile tools for the delivery of DNA, DNA-related, and many other therapeutic molecules [6,7,29], Liposomes are spherical vesicles that consist of an aqueous compartment enclosed in a phospholipid bilayer. If multiple bilayers of lipids are formed around the primary core, the structures that are generated are known as multilamellar vesicles (MLVs). MLVs are formed spontaneously by reconstitution of lipid films in aqueous media. Small unilamellar vesicles (SUVs) of specific size (100-500 nm) are produced by high-pressure extrusion of MLVs through polycarbonate membranes. SUVs (25-90nm) are also obtained by sonication of MLVs or larger SUVs, by detergent dialysis [62] and by many other, less important methods. Both hydrophilic and... 

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