Stress field analysis and its effect on selection of optimal well trajectory in directional drilling (case study: southwest of Iran)

Given the complexities of reservoir exploration and development, it is vital to understand the geomechanical properties of the reservoir and well in the drilling operation. In constructing a mechanical model of the earth, a combination of environmental geomechanical parameters, as well as the magnitude and direction of stresses, is used. In this study, stress analysis and its effect on azimuth well in deviated drilling in an oil field located in southwestern Iran are investigated. Necessary geomechanical parameters are estimated using density and slowness logs of sonic waves (shear and compression). The Mohr–Coulomb failure criterion is followed to determine a safe mud weight window. A mechanical model of the earth is designed using laboratory data and well logging, and it is validated by the results obtained from laboratory rock mechanics using the calibrated core samples. The results show that drilling in the azimuth at about 135° with an angle of about 15° is the most stable path for the well in the carbonate reservoir formation in the studied oil field.

Results of recording sonic waves by seismic stations in the territory of Karelia

In spite of a relatively low seismic activity level, the detailed study of Karelia is not only of theoretical, scientific interest, but is also of practical value which has increased markedly because there are big industrial complexes, gas pipelines and hydrotechnical facilities in the region. The results of recording sonic waves of various nature by stationary and mobile seismic stations are presented. For the observation period 2000—2020 an array of seismic data has been accumulated. In order to correctly understand the nature of the signals under consideration, it should be noted that North Karelia is known to belong to seismic regions, where 5-point earthquakes have taken place earlier. They were distinguished from earthquakes generated by frost cracking by both visual and instrumental data. They are known throughout Fennoscandia. This group comprises both tremors during frost cracking of the soil, primarily with a sharp change in temperature, and frost cracking of ice in inland water bodies. To decide on the nature of ground shaking, it is necessary to pay attention to such signs as the limited area of oscillations and the nature of the wave record. As a result of seismic monitoring of Karelia, the following frost quakes were also recorded: the passage of the bolidi, the take-off of an aircraft, blasting operations during the disposal of ammunition and mining in the immediate vicinity of residential areas and industrial facilities. A wide range of possible sources and examples of sound waveforms are shown. The data obtained indicate the possibility of some shocks with a force of up to 4ѕ5 points in the immediate vicinity of the place of registration, what should be considered in the routine processing of seismic events and seismic hazard assessment in the southeastern Fennoscandian Shield.

Ultrasound-assisted aqua-mediated synthesis of multi-substituted tetrahydropyridine-3-carboxylates using N-carboxymethyl-3-pyridinium hydrogensulfate ([N-CH2CO2H-3-pic]+HSO4−) as a new efficient ionic liquid catalyst

A simple, straightforward, and ultrasound-promoted method for the preparation of some highly functionalized tetrahydropyridines reported via pseudo five-component reaction of (hetero)aromatic aldehydes, different anilines, and alkyl acetoacetates in the presence of [N-CH2CO2H-3-pic]+HSO4−, as a novel ionic liquid, in green aqueous medium. The IL was synthesized utilizing simple and easily-handled substrates and characterized by FT-IR, 1H NMR, 13C NMR, GC-MASS, FESEM, EDX, and TGA/DTG techniques. The procedure contains some highlighted aspects which are: (a) performing the MCR in the presence of aqua and sonic waves, as two main important and environmentally benign indexes in green and economic chemistry, (b) high yields of products within short reaction times, (c) convenient work-up procedure, (d) preparing the new IL via simple substrates and procedure.

Prediction of Maritime Pine Boards Modulus of Elasticity by Means of Sonic Testing on Green Timber

Timber buildings are experiencing a rapid diffusion due to their good performance and their sustainability; however, some steps of structural timber production process, such as drying, are energy-intensive and environmentally impactful, and many wood species are also affected by low yield. Therefore, it would be important to determine the quality of the green material, that is, in wet condition, before undergoing the most impactful and expensive production steps. This paper describes a research aimed at quantifying the variation of the dynamic modulus of elasticity MoEdyn, which is commonly used for structural timber mechanical grading, from wet to dry condition in Sardinian maritime pine boards to be used for the production of laminated timber, and to examine the relationship between wet and dry MoEdyn. The MoEdyn was determined from measurements of the velocity of sonic waves propagating through the boards. The results show that the dry MoEdyn can be estimated starting from boards sonic testing in the wet condition, so providing a basis for implementing Sardinian maritime pine pre-grading in order to obtain the reduction of manufacturing costs, the abatement of environmental impact, and the increase of structural grade yield.

Advanced Layered Composite Structures for Underwater Acoustic Applications

The detection of underwater objects is one of the most critical technologies, and there have been constant efforts for developing sophisticated sonar systems in naval warfare. Against such efforts, the countermeasure of hiding underwater vehicles, equipment and weapons is another technological challenge. One of the effective countermeasures against sonic detection for the submarines and other underwater objects, such as naval mines, is to employ composite/hybrid materials to prevent ease of detection. Geometrical forms, shapes and layers, along with the tuning of the acoustical impedance, lead to a considerable decrease of the sonar signals via absorption of the sonic waves. In this study, an original and novel design of multi-layered composite/hybrid structure was developed and underwater acoustic testing procedures of reflection, transmission and scattering were applied in 80 kHz100 kHz frequency range. The findings obtained in this study showed that the multi-layered composite/hybrid materials with porous structure possess much lower values in millivolt than steel plates and might be potential candidates as covering and/or casing materials for underwater mines to reduce the acoustical signature against detection and identification.

Using the coronary lithotripsy system for coronary artery disease

Severe coronary artery calcification increases percutaneous treatment complexity and the risk of intraprocedural complications, affecting acute and long-term outcomes. Current use of specialty balloons and atherectomy technologies is limited due to the higher risk of complications, degree of technical difficulty and operator experience. Intravascular lithotripsy (IVL) is a novel technology for severe calcified coronary artery disease that facilitates vessel preparation, enhancing vessel compliance. IVL system emits sonic waves that penetrate through vascular layers and disrupt both superficial and deep calcium, leaving the soft tissue unharmed. The purpose of the present review is to provide a summary of the evidence currently available on this therapy, including a practical description of the components and function of the shockwave coronary IVL system.

345 Digital Technologies Ease the Burden of Pasture Intake Measurements: A New Hope

A short while ago, in fields not so far away, graziers guessed forage mass and intake of grazing livestock in pastures. Then a period ensued where only laborious, expensive methods existed to measure the same. Faced with such a galactic dilemma, researchers made one of two practical choices: 1) collect minimal amounts of pasture growth information and give up precision, or 2) ignore pasture growth and forage measures altogether. Neither approach provides the data needed to describe forage intake of grazing animals. Smart devices — now carrying 120 million times more computing power than navigation systems onboard Apollo 11 — bring a new hope to pasture researchers, managers and farmers. This paper evaluates technological advances that enable the next generation of pasture measurements (including animal intake) using sensors. The list of sensors-based tools includes platemeters, digital rules, sonic waves, stereo photography, dual-tuned ultrasound, surround sound, lasers, light bars, and satellite images. These tools — coupled with artificial intelligence systems — give creative thinkers new ways to measure, monitor and manage forage intake in pastures. It’s the future.

Viscoelastic type magnetic effects and self-gravity on the propagation of MHD waves

We take up the challenge to explain the correlation between the Jeans instability topic towards star formation within the accelerated expansion of universe and the role of torsional shear-like Alfven waves in triggering the formation of network patterns, by proposing new mathematical models for self-gravitating interstellar non ideal MHD plasmas. The diffusion of the gravitational field is included via a parabolic Einstein’s equation with the cosmological constant, whereas anomalous resistive features are described through non ideal Ohm’s laws incorporating inertia terms, to account of relaxation and retardation magnetic responses. We perform a spectral analysis to test the stability properties of the novel constitutive settings where dissipative and elastic devices act together, by emphasizing the differences with previous models. As a main result, we highlight the definition of a lower critical threshold, here called the Jeans-Einstein wavenumber, against collapse formation towards the formation of longitudinal gravito-magneto-sonic waves and transverse non gravitational Alfven waves exhibiting larger effective wavespeeds, due to the hyperbolic-parabolic diffusion of the magnetic field. Consequently shorter collisional times are allowable so, beyond the plasma-beta, another interesting key point is the definition of the Ohm number to revisit the timescale topic, towards reviewed Reynolds and Lundquist numbers able to better capture the microphysical phenomena of Magnetic Reconnection in narrow diffusion regimes.