Acoustic Properties of the Cod Swimbladder

1973 ◽  
Vol 58 (3) ◽  
pp. 797-820 ◽  
Author(s):  
OLAV SAND ◽  
A. D. HAWKINS
Keyword(s):  
Resonance Frequency ◽  
Relative Sensitivity ◽  
Acoustic Properties ◽  
Gas Bubble ◽  
A Value ◽  
Hearing Organ ◽  
Different Depths ◽  
Hearing Range ◽  
The Difference ◽  
Pressure Changes

1. The resonance frequency and damping of the swimbladder were measured for intact living cod at different depths. 2. At adaptation depth, the resonance frequency (fχ) of the organ was much higher than that predicted for an unrestrained gas bubble of similar volume. However, at much greater depths (where the hydrostatic pressure was 2 or more times greater than the adaptation pressure) fχ was only higher than expected by a factor of 1·25, and changed with depth in the manner of a free gas bubble. 3. The elevated values at greater depths can be explained in terms of the difference in shape between the swimbladder and an ideal spherical bubble, together with a clight effect from the surrounding tissues. We have calculated that the shear modulus of these tissues (µ1) has a value of approximately 1·7 x 106 dyne/cm2. However, we have suggested that the much higher elevation of fχ found at the adaptation depth results from a large increase in µ1 (by a factor of between 6 and 120). This increase may be the result of a maintained muscle tonus. 4. There is an immediate drop in fχ as a fish is moved to a new depth, but the elevated values are rapidly restored with time. This process of adjustment is too rapid to be accounted for by the restoration of the swimbladder to its former volume by the secretion or absorption of gas. It is possible that it is achieved by a muscular mechanism which restores µ1 to the former high value. 5. Though the maintenance of fχ at a high value may reflect mechanical processes concerned with the hydrostatic function of the swimbladder, or with the detection of static pressure changes, we suggest that it may also be of some value if the swimbladder is used as an accessory hearing organ. The maintenance of an fχ well above the hearing range of the fish ensures that the relative sensitivity of the animal to different frequencies does not alter with changes in depth.

scholarly journals ANALYSIS OF ACOUSTIC ANISOTROPY PARAMETERS OF PYROXENE-MAGNETITE ROCKS OF THE PISCHANKA STRUCTURE

2020 ◽  
pp. 40-45
Author(s):  
I. Bezrodna ◽  
V. Svystov ◽  
D. Bezrodny
Keyword(s):  
Acoustic Properties ◽  
Significant Heterogeneity ◽  
Depth Range ◽  
Transverse Waves ◽  
Acoustic Anisotropy ◽  
Micro Cracks ◽  
Acoustic Tensor ◽  
Transverse Isotropic ◽  
Different Depths ◽  
The Difference

The analysis of the results of acoustic properties of rocks study of Pischans`ka iron-ore structure is presented. The aim of the work is to establish the features of the distribution of acoustic properties and parameters of acoustic anisotropy in samples of core rocks selected from the well No. 3 of the Pischans`ka structure to determine the nature of its occurrence. A sample of 35 samples from the depth range 144-273 m is divided into 3 groups of rocks, namely: magnetite-pyroxene, quartz-magnetitepyroxene and biotite-amphibole crystalline shales. Based on an invariant polarization method, a number of acoustic laboratory measurements have been carried out. The values of the measured phase velocities "quasi-longitudinal" and two "quasi-transverse" waves at the stage of measurements showed significant acoustic anisotropy of the rocks. The ranges of the measured speeds of the collection samples are 7661 ÷ 5046 m / s for longitudinal waves and 4232 ÷ 2648 m/s for transverse ones. The difference in values measured for each of the sides of the cubic rhombic dodecahedron is from 100 to 800 m / s and from 0 to 500 m/s for Vp and Vs, respectively. The parameters of an acoustic ellipsoid were calculated, on the basis of which the division of samples into 3 main groups has been performed, according to the acoustic texture: acoustically linear, shale and rhombic. Separately, a group of samples with a more complex texture was discovered. The analysis of coefficients of anisotropy by different methods is carried out: longitudinal, transverse and relative acoustic anisotropy. Most of the samples are characterized by low or average acoustic anisotropy (from 2 to 7 %). A group of highly anisotropic rocks (11–14 %), represented by samples of biotite-amphibole crystalline silicates, is singled out. According to the parameters of the acoustic tensor of most samples, the transverse isotropic type of symmetry inherent to samples from the depth intervals 174–220 m and 222–232 m, while the smaller part is rhombic, is inherent. Differences in the parameters of anisotropy of samples can be explained by the significant heterogeneity of their textures, namely: micro cracks, minerals of various sizes, shapes and orientations. The results of the research show that the acoustic properties of the samples are quite heterogeneously distributed along the investigated depth range. This indicates the difficult conditions for the formation of rocks at different depths and the presence of different types of deformations, which accompanied the formation of the Pischans`ka structure.

scholarly journals The Water Footprint of Primary and Secondary Processing of Beef from Different Cattle Breeds: A Value Fraction Allocation Model

2021 ◽  
Vol 13 (12) ◽  
pp. 6914
Author(s):  
Frikkie Alberts Maré ◽  
Henry Jordaan
Keyword(s):  
Water Footprint ◽  
Negative Relationship ◽  
High Water ◽  
Allocation Model ◽  
Cattle Breeds ◽  
A Value ◽  
Average Production ◽  
High Water Intake ◽  
The Difference ◽  
By Products

The high water intake and wastewater discharge of slaughterhouses have been a concern for many years. One neglected factor in previous research is allocating the water footprint (WF) to beef production’s different products and by-products. The objective of this article was to estimate the WF of different cattle breeds at a slaughterhouse and cutting plant and allocate it according to the different cuts (products) and by-products of beef based on the value fraction of each. The results indicated a negative relationship between the carcass weight and the processing WF when the different breeds were compared. Regarding a specific cut of beef, a kilogram of rib eye from the heaviest breed had a processing WF of 614.57 L/kg, compared to the 919.91 L/kg for the rib eye of the lightest breed. A comparison of the different cuts indicated that high-value cuts had higher WFs than low-value cuts. The difference between a kilogram of rib eye and flank was 426.26 L/kg for the heaviest breed and 637.86 L/kg for the lightest breed. An option to reduce the processing WF of beef is to lessen the WF by slaughtering heavier animals. This will require no extra investment from the slaughterhouse. At the same time, the returns should increase as the average production inputs per kilogram of output (carcass) should reduce, as the slaughterhouse will process more kilograms.

scholarly journals Acoustic Characterization of Some Steel Industry Waste Materials

2021 ◽  
Vol 11 (13) ◽  
pp. 5924
Author(s):  
Elisa Levi ◽  
Simona Sgarbi ◽  
Edoardo Alessio Piana
Keyword(s):  
Thermal Characteristic ◽  
Environmental Benefits ◽  
Acoustic Properties ◽  
Physical Parameters ◽  
Industry Waste ◽  
Acoustic Characterization ◽  
Minimization Procedure ◽  
The Difference ◽  
By Products

From a circular economy perspective, the acoustic characterization of steelwork by-products is a topic worth investigating, especially because little or no literature can be found on this subject. The possibility to reuse and add value to a large amount of this kind of waste material can lead to significant economic and environmental benefits. Once properly analyzed and optimized, these by-products can become a valuable alternative to conventional materials for noise control applications. The main acoustic properties of these materials can be investigated by means of a four-microphone impedance tube. Through an inverse technique, it is then possible to derive some non-acoustic properties of interest, useful to physically characterize the structure of the materials. The inverse method adopted in this paper is founded on the Johnson–Champoux–Allard model and uses a standard minimization procedure based on the difference between the sound absorption coefficients obtained experimentally and predicted by the Johnson–Champoux–Allard model. The results obtained are consistent with other literature data for similar materials. The knowledge of the physical parameters retrieved applying this technique (porosity, airflow resistivity, tortuosity, viscous and thermal characteristic length) is fundamental for the acoustic optimization of the porous materials in the case of future applications.

Berechnung kinetischer Isotopeneffekte für die Reaktion von Methyljodid mit Cyanid-Ion

1966 ◽  
Vol 21 (9) ◽  
pp. 1377-1384
Author(s):  
A. V. Willi
Keyword(s):  
Transition State ◽  
Secular Equation ◽  
Isotope Effects ◽  
Force Constants ◽  
Bond Breaking ◽  
Bending Force ◽  
A Value ◽  
Order Of Magnitude ◽  
Deuterium Isotope Effects ◽  
The Difference

Kinetic carbon-13 and deuterium isotope effects are calculated for the SN2 reaction of CH3I with CN-. The normal vibrational frequencies of CH3I, the transition state I · · · CH3 · · · CN, and the corresponding isotope substituted reactants and transition states are evaluated from the force constants by solving the secular equation on an IBM 7094 computer.Values for 7 force constants of the planar CH3 moiety in the transition state (with an sp2 C atom) are obtained by comparison with suitable stable molecules. The stretching force constants related to the bonds being broken or newly formed (fCC, fCC and the interaction between these two stretches, /12) are chosen in such a way that either a zero or imaginary value for νʟ≠ will result. Agreement between calculated and experimental methyl-C13 isotope effects (k12/ k13) can be obtained only in sample calculations with sufficiently large values of f12 which lead to imaginary νʟ≠ values. Furthermore, the difference between fCI and fCC must be small (in the order of 1 mdyn/Å). The bending force constants, fHCI and fHCC, exert relatively little influence on k12/k13. They are important for the D isotope effect, however. As soon as experimental data on kH/kD are available it will be possible to derive a value for fHCC in the transition state if fHCI is kept constant at 0.205 mdynA, and if fCI, fCC and f12 are held in a reasonable order of magnitude. There is no agreement between experimental and calculated cyanide-C13 isotope effects. Possible explanations are discussed. — Since fCI and fCC cannot differ much it must be concluded that the transition state is relatively “symmetric”, with approximately equal amounts of bond making and bond breaking.

The early attentional pancake: Lack of selection in depth for rapid exogenous cueing

2021 ◽  
Author(s):  
Ryan Edward O'Donnell ◽  
Kyrie Murawski ◽  
Ella Herrmann ◽  
Jesse Wisch ◽  
Garrett D. Sullivan ◽  
...  
Keyword(s):  
Reaction Time ◽  
Binocular Disparity ◽  
Dimensional Space ◽  
Exogenous Attention ◽  
3 Dimensional ◽  
Exogenous Cueing ◽  
Different Depths ◽  
Depth Cueing ◽  
The Difference ◽  
Attentional Selectivity

There have been conflicting findings on the degree to which exogenous/reflexive visual attention is selective for depth, and this issue has important implications for attention models. Previous findings have attempted to find depth-based cueing effects on such attention using reaction time measures for stimuli presented in stereo goggles with a display screen. Results stemming from such approaches have been mixed, depending on whether target/distractor discrimination was required. To help clarify the existence of such depth effects, we have developed a paradigm that measures accuracy rather than reaction time in an immersive virtual-reality environment, providing a more appropriate context of depth. Four modified Posner Cueing paradigms were run to test for depth-specific attentional selectivity. Participants fixated a cross while attempting to identify a rapidly masked letter that was preceded by a cue that could be valid in depth and side, depth only, or side only. In Experiment 1, a potent cueing effect was found for side validity and a weak effect was found for depth. Experiment 2 controlled for differences in cue and target sizes when presented at different depths, which caused the depth validity effect to disappear entirely even though participants were explicitly asked to report depth and the difference in virtual depth was extreme (20 vs 300 meters). Experiments 3a and 3b brought the front depth plane even closer (1 m) to maximize effects of binocular disparity, but no reliable depth cueing validity was observed. Thus, it seems that rapid/exogenous attention pancakes 3-dimensional space into a 2-dimensional reference frame.

Analisis Skrining Fitokimia dan Aktivitas Antioksidan Ekstrakk Biji Sangrai Kopi Robusta (Coffea canephora) dari Tanaman Hasil Pemupukan Organik dan Anorganik

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Farah Aida Qotrun Nada ◽  
Tintrim Rahayu ◽  
Ari Hayati
Keyword(s):  
Statistical Tests ◽  
Linear Regression Analysis ◽  
Coffea Canephora ◽  
Coffee Bean ◽  
Phytochemical Screening ◽  
Robusta Coffee ◽  
A Value ◽  
Coffee Beans ◽  
Ic50 Value ◽  
The Difference

Ground coffee is coffee beans that have been roasted, ground or ground so that they have a smooth shape. The purpose of this study was to determine the content of compounds in robusta coffee roasted seed extract (Coffea canephora) from plants produced by organic and inorganic fertilization, and to know the difference in compounds between the results of organic and inorganic fertilization. The characteristics of phytochemical screening were carried out qualitatively on alkaloids, flavonoids, tannins, terpenoids and saponins and the antioxidant activity was carried out by the DPPH (1,1-dipenyl-2-picrihidrazil) method. Phytochemical screening characteristic test results show that robusta coffee bean extract extract from the results of organic and inorganic fertilization both contain flavonoids, alkaloids, tannins, and saponins, while the antioxidant test activity of robusta coffee beans extracts shows differences based on the results of statistical tests of linear regression analysis with the IC50 value the highest antioxidant content was inorganic coffee roasted bean extract only 14.0629 ppm compared to the organic roasted extract with a value of 30.6159 ppmKeywords: Robusta Coffee (Coffea canophora), Phytochemical Screening, DPPH MethodABSTRAKKopi bubuk adalah biji kopi yang telah disangrai digiling atau ditumbuk sehingga mempunyai bentuk halus. Tujuan dari penelitian ini adalah untuk mengetahui kandungan senyawa dalam ekstrak biji sangrai kopi robusta (Coffe canephora) dari tanaman hasil pemupukan organik dan anorganik, dan mengetahui perbedaan senyawa antara hasil pemupukan organik dan anorganik. Karakteristik skrining fitokimia dilakukan secara kualitatif yang dilakukan terhadap alkaloid, flavonoid, tanin, terpenoid dan saponin dan aktivitas antioksidan dilakukan dengan metode DPPH (1,1-difenil-2-pikrihidrazil). Hasil uji karakteristik skrining fitokimia menunjukkan bahwa ekstrak biji sangrai kopi robusta dari hasil pemupukan oganik dan anorganik keduanya sama mengandung senyawa flavonoid, alkaloid, tanin, dan saponin,  sedangkan pada aktifitas uji antioksidan ekstrak biji sangrai kopi robusta menunjukan perbedaan berdasarkan hasil uji statistik analisis regresi linear dengan nilai IC50 kadar antioksidan paling tinggi adalah ekstrak biji sangrai kopi anorganik hanya 14,0629 ppm dibandingkan dengan ekstrak sangrai dari organik dengan nilai 30,6159 ppm.Kata kunci : Kopi Robusta (Coffea canophera), Skrining Fitokimia, Metode DPPH

Predicting the Influence of Damping Devices on the Stability Margin of an Annular Combustor

2017 ◽  
Author(s):  
Max Zahn ◽  
Michael Betz ◽  
Moritz Schulze ◽  
Christoph Hirsch ◽  
Thomas Sattelmayer
Keyword(s):  
Resonance Frequency ◽  
Stability Margin ◽  
Numerical Approach ◽  
Acoustic Mode ◽  
Acoustic Properties ◽  
Azimuthal Mode ◽  
Acoustic Damping ◽  
Linearized Euler Equations ◽  
Annular Combustor ◽  
The Impact

A numerical modeling approach based on linearized Euler equations is applied to predict the linear stability of an annular combustor with and without dampers. The acoustic properties of all relevant combustor components such as damping devices, swirl burner characteristics, swirl flame dynamics, and combustor exit are individually evaluated via experimental and numerical approaches. All of the components are incorporated subsequently into the combustor model using impedances and acoustic transfer matrices to obtain an efficient procedure. This study focuses on using this approach to predict an annular combustor’s stability margin and to assess how dampers influence the modal dynamics of the first azimuthal mode. Stability predictions are successfully validated with experimental data. Different combustor components’ contributions to the acoustic damping of the entire system is also determined based on that numerical approach. Damper application in combustors can engender uncertainties in resonance frequency in the case of hot-gas ingestion. The impact of “detuned” resonators on the predicted damping rates with respect to a deviation in the resonance frequency and the eigenfrequency of the attenuated acoustic mode is therefore evaluated. The influence of dampers on the annular combustor’s stability margin is also determined.

scholarly journals Physical controls on the storage of methane in landfast sea ice

2014 ◽  
Vol 8 (3) ◽  
pp. 1019-1029 ◽  
Author(s):  
J. Zhou ◽  
J.-L. Tison ◽  
G. Carnat ◽  
N.-X. Geilfus ◽  
B. Delille
Keyword(s):  
Sea Ice ◽  
Bubble Formation ◽  
Gas Bubble ◽  
Physical Processes ◽  
Ice Melt ◽  
Physical Controls ◽  
The Difference ◽  
Landfast Sea Ice ◽  
Ice Water ◽  
Brine Concentration

Abstract. We report on methane (CH4) dynamics in landfast sea ice, brine and under-ice seawater at Barrow in 2009. The CH4 concentrations in under-ice water ranged from 25.9 to 116.4 nmol L−1sw, indicating a supersaturation of 700 to 3100% relative to the atmosphere. In comparison, the CH4 concentrations in sea ice ranged from 3.4 to 17.2 nmol L−1ice and the deduced CH4 concentrations in brine from 13.2 to 677.7 nmol L−1brine. We investigated the processes underlying the difference in CH4 concentrations between sea ice, brine and under-ice water and suggest that biological controls on the storage of CH4 in ice were minor in comparison to the physical controls. Two physical processes regulated the storage of CH4 in our landfast ice samples: bubble formation within the ice and sea ice permeability. Gas bubble formation due to brine concentration and solubility decrease favoured the accumulation of CH4 in the ice at the beginning of ice growth. CH4 retention in sea ice was then twice as efficient as that of salt; this also explains the overall higher CH4 concentrations in brine than in the under-ice water. As sea ice thickened, gas bubble formation became less efficient, CH4 was then mainly trapped in the dissolved state. The increase of sea ice permeability during ice melt marked the end of CH4 storage.

ETUDE DU POUVOIR NUTRITIF EN PHOSPHORE DE CERTAINS SOLS DU QUEBEC A L'AIDE DU 32P

1976 ◽  
Vol 56 (3) ◽  
pp. 285-291
Author(s):  
B. TOUATI ◽  
C. PLENCHETTE ◽  
M. TABI
Keyword(s):  
Soil Phosphorus ◽  
Phosphate Fertilizer ◽  
Soil Types ◽  
K Value ◽  
Type Experiment ◽  
A Value ◽  
The Difference ◽  
The Way

In a pot-type experiment with ryegrass, 32P was used to label isotopically exchangeable soil phosphorus as well as a phosphate fertilizer. The tagging of both forms of phosphorus enable us to determine the pool (L) for soil reserves and the A value which is the availability of these reserves in the presence of fertilizer. The authors establish correlations between the ratio K = L/A and the assimilable phosphorus as determined by the Bray II method, and also between K and the "extra" phosphorus. The authors state that the latter was the difference between the plant phosphorus with and without fertilizer. From this study it is concluded: (1) that the K value seems to be a better criterion than the amount of assimilable phosphorus to estimate the phosphorus fertility of a soil; (2) that the study of the variation of the K value according to the soil types informs us about the reserves behavior and about the way of nutrition for the plant. The calculation of the K value is aimed toward a more adequate fertilization for given types of soil.

scholarly journals Archie's law – a reappraisal

Solid Earth ◽  
2016 ◽  
Vol 7 (4) ◽  
pp. 1157-1169 ◽  
Author(s):  
Paul W. J. Glover
Keyword(s):  
Systematic Errors ◽  
Apparent Paradox ◽  
Archie’S Law ◽  
A Value ◽  
The Difference ◽  
Reservoir Parameter ◽  
Parameter Values ◽  
Electrical Data ◽  
Extra Parameter ◽  
Better Than

Abstract. When scientists apply Archie's first law they often include an extra parameter a, which was introduced about 10 years after the equation's first publication by Winsauer et al. (1952), and which is sometimes called the “tortuosity” or “lithology” parameter. This parameter is not, however, theoretically justified. Paradoxically, the Winsauer et al. (1952) form of Archie's law often performs better than the original, more theoretically correct version. The difference in the cementation exponent calculated from these two forms of Archie's law is important, and can lead to a misestimation of reserves by at least 20 % for typical reservoir parameter values. We have examined the apparent paradox, and conclude that while the theoretical form of the law is correct, the data that we have been analysing with Archie's law have been in error. There are at least three types of systematic error that are present in most measurements: (i) a porosity error, (ii) a pore fluid salinity error, and (iii) a temperature error. Each of these systematic errors is sufficient to ensure that a non-unity value of the parameter a is required in order to fit the electrical data well. Fortunately, the inclusion of this parameter in the fit has compensated for the presence of the systematic errors in the electrical and porosity data, leading to a value of cementation exponent that is correct. The exceptions are those cementation exponents that have been calculated for individual core plugs. We make a number of recommendations for reducing the systematic errors that contribute to the problem and suggest that the value of the parameter a may now be used as an indication of data quality.

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