On properties of seawater defined by temperature, salinity, and pressure

2021 ◽  
Vol 79 (3) ◽  
pp. 121-147
Author(s):  
George Veronis
Keyword(s):  
Vertical Direction ◽  
Great Depth ◽  
Local Potential ◽  
Potential Density ◽  
Marine Research ◽  
Station Data ◽  
Starting Point ◽  
The World ◽  
Gravitational Stability

Hydrographic station data, consisting principally of temperature and salinity determinations, have been used by physical oceanographers to develop a climatological picture of the distribution of these quantities in the oceans of the world. Density as determined by Knudsen's formula, taken together with hydrostatic and geostrophic dynamics, also provides a crude picture of oceanic flow. However, the data probably contain substantially more information than has been derived from them in the past.The quantity that is orthogonal to potential-density curves in the S plane is suggested as a useful variable to complement the information contained in potential density. The derivation of this quantity, denoted by τ in this paper, is straightforward. A polynomial expression for τ that is suitable for computer calculations of τ from hydrographic station data is given. Shown are examples of hydrographic station data from the Atlantic plotted on the τσ diagram. The information contained in the τσ diagram shows many of the features exhibited in the TS plane. Vertical sections of τ appear to provide information about mixing in different parts of the Atlantic. The distribution of τ for abyssal waters at selected stations in the oceans of the world resembles the distribution of abyssal density as plotted by Lynn and Reid (1968). From the data presented, it appears that τ may serve as a good tracer for abyssal water movements.Since τ is defined to be orthogonal to σ, the expectation is that τ is a dynamically passive variable. However, since σ does not correlate with abyssal densities, it appears to lose dynamical significance at great depth, and τ assumes dynamical significance because of its orthogonality to σ. This unexpected feature leads to an exploration of the dynamical significance of σ. A natural starting point is the question of stability of abyssal water.A distinction is made between stability as determined by in situ determinations and as determined by the potential-density (σ) distribution. Simple examples are presented to show that analysis based on σ alone can lead to incorrect conclusions about gravitational stability of the water in the abyssal ocean. The reason is that seawater is a multicomponent thermodynamic system, and the thermodynamic coefficients are functions of pressure, salinity, and temperature. This functional dependence leads to adjustments in density as a water particle moves adiabatically in the vertical direction so that a layer of water that appears to be unstable near the surface may be stable (as determined by in situ determination) at great depth. A local potential density, which is simply the vertical integral of the in situ stability, is derived. This quantity gives a precise picture of gravitational stability in the vertical direction. Some distributions of local potential density are shown.Originally published May 15, 1972, in the Journal of Marine Research 30(2), 227???255.

scholarly journals An Assessment of Orthobaric Density in the Global Ocean

2005 ◽  
Vol 35 (11) ◽  
pp. 2054-2075 ◽  
Author(s):  
Trevor J. McDougall ◽  
David R. Jackett
Keyword(s):  
Southern Hemisphere ◽  
World Ocean ◽  
Ocean Basin ◽  
Ocean Modeling ◽  
Global Ocean ◽  
Potential Density ◽  
Vertical Coordinate ◽  
The World ◽  
Density Surface

Abstract Orthobaric density has recently been advanced as a new density variable for displaying ocean data and as a coordinate for ocean modeling. Here the extent to which orthobaric density surfaces are neutral is quantified and it is found that orthobaric density surfaces are less neutral in the World Ocean than are potential density surfaces referenced to 2000 dbar. Another property that is important for a vertical coordinate of a layered model is the quasi-material nature of the coordinate and it is shown that orthobaric density surfaces are significantly non-quasi-material. These limitations of orthobaric density arise because of its inability to accurately accommodate differences between water masses at fixed values of pressure and in situ density such as occur between the Northern and Southern Hemisphere portions of the World Ocean. It is shown that special forms of orthobaric density can be quite accurate if they are formed for an individual ocean basin and used only in that basin. While orthobaric density can be made to be approximately neutral in a single ocean basin, this is not possible in both the Northern and Southern Hemisphere portions of the Atlantic Ocean. While the helical nature of neutral trajectories (equivalently, the ill-defined nature of neutral surfaces) limits the neutrality of all types of density surface, the inability of orthobaric density surfaces to accurately accommodate more than one ocean basin is a much greater limitation.

Dreams Give Birth to Reality”. Engraving Austroseraphicum Coelum as an Attempt to Create a New Reality by the Spanish Habsburgs Dynastic Propaganda / Sny rodzą rzeczywistość…”. Grafika Austroseraphicum Coelum jako próba kreowania nowej rzeczywistości za pomocą propagandy dynastycznej Habsburgów hiszpańskich

2014 ◽  
Vol 39 (1) ◽  
Author(s):  
Jan Kurowiak
Keyword(s):  
Seventeenth Century ◽  
The Netherlands ◽  
General Condition ◽  
Symbolic System ◽  
Political Situation ◽  
Mission Of God ◽  
Starting Point ◽  
The World ◽  
The Church

AbstractAs a work of propaganda, graphics Austroseraphicum Coelum Paulus Pontius should create a new reality, make appearances. The main impression while seeing the graphics is the admiration for the power of Habsburgs, which interacts with the power of the Mother of God. She, in turn, refers the viewer to God, as well as Franciscans placed on the graphic, they become a symbol of the Church. This is a starting point for further interpretation of the drawing. By the presence of certain characters, allegories, symbols, we can see references to a particular political situation in the Netherlands - the war with the northern provinces of Spain. The message of the graphic is: the Spanish Habsburgs, commissioned by the mission of God, they are able to fight all of the enemies, especially Protestants, with the help of Immaculate and the Franciscans. The main aim of the graphic is to convince the viewer that this will happen and to create in his mind a vision of the new reality. But Spain was in the seventeenth century nothing but a shadow of former itself (in the time of Philip IV the general condition of Spain get worse). That was the reason why they wanted to hold the belief that the empire continues unwavering. The form of this work (graphics), also allowed to export them around the world, and the ambiguity of the symbolic system, its contents relate to different contexts, and as a result, the Habsburgs, not only Spanish, they could promote their strength everywhere. Therefore it was used very well as a single work of propaganda, as well as a part of a broader campaign

Ups and Downs

2018 ◽  
Author(s):  
Roy Livermore
Keyword(s):  
Mantle Convection ◽  
Laboratory Experiments ◽  
Inner Core ◽  
Computer Modelling ◽  
Great Depth ◽  
New Horizons ◽  
The Core ◽  
The Earth ◽  
The World ◽  
The 1960S

Despite the dumbing-down of education in recent years, it would be unusual to find a ten-year-old who could not name the major continents on a map of the world. Yet how many adults have the faintest idea of the structures that exist within the Earth? Understandably, knowledge is limited by the fact that the Earth’s interior is less accessible than the surface of Pluto, mapped in 2016 by the NASA New Horizons spacecraft. Indeed, Pluto, 7.5 billion kilometres from Earth, was discovered six years earlier than the similar-sized inner core of our planet. Fortunately, modern seismic techniques enable us to image the mantle right down to the core, while laboratory experiments simulating the pressures and temperatures at great depth, combined with computer modelling of mantle convection, help identify its mineral and chemical composition. The results are providing the most rapid advances in our understanding of how this planet works since the great revolution of the 1960s.

The Paradox of “A High Standard of Public Honesty”

2017 ◽  
Author(s):  
James Kennedy ◽  
Ronald Kroeze
Keyword(s):  
The Netherlands ◽  
Early Modern ◽  
Side Effect ◽  
High Standard ◽  
Dutch Republic ◽  
Liberal Politics ◽  
Patronage Politics ◽  
Starting Point ◽  
The World ◽  
Late Nineteenth

This chapter takes as its starting point the contemporary idea that the Netherlands is one of the least corrupt countries in the world; an idea that it dates back to the late-nineteenth and early-twentieth centuries. In this chapter, the authors explain how corruption was controlled in the Netherlands against the background of the rise and fall of the Dutch Republic, modern statebuilding and liberal politics. However, the Dutch case also presents some complexities: first, the decrease in some forms of corruption was due not to early democratization or bureaucratization, but was rather a side-effect of elite patronage-politics; second, although some early modern forms of corruption disappeared around this period, new forms have emerged in more recent times.

The Vyredox and Nitredox Methods of in situ Treatment of Groundwater

1988 ◽  
Vol 20 (3) ◽  
pp. 149-163 ◽  
Author(s):  
Carol Braester ◽  
Rudolf Martinell
Keyword(s):  
Water Treatment ◽  
Surface Water ◽  
Traditional Method ◽  
Treatment Method ◽  
Nitrate Treatment ◽  
The Past ◽  
The World ◽  
Nitrate And Nitrite ◽  
Iron And Manganese

Nearly one fifth of all water used in the world is obtained from groundwater. The protection of water has become a high priority goal. During the last decades pollution of water has become more and more severe. Today groundwater is more and more used in comparison with surface water. Recently we have seen accidents, which can pollute nearly all surface water very quickly. Generally the groundwater is easier to protect, as well as cheaper to purify, and above all it is of better quality than the surface water. During the past two decades, alternatives to the traditional method of treating the water in filters have been developed, that is in situ water treatment i.e. the VYREDOX and NITREDOX methods. The most common problem regarding groundwater is too high content of iron and manganese, which can be reduced with the VYREDOX method. In some areas today there are severe problems with pollution by hydrocarbons and nitrate as well, and with modification of the VYREDOX treatment method it is used for hydrocarbon and nitrate treatment as well. The method to reduce the nitrate and nitrite is known as the NITREDOX method.

scholarly journals Contracting in land and natural resources: a tale of exclusion

2021 ◽  
Vol 17 (1) ◽  
pp. 145-153
Author(s):  
Federica Violi
Keyword(s):  
Natural Resources ◽  
Large Scale ◽  
Sustainable Development Goals ◽  
Host Countries ◽  
Developmental Needs ◽  
Starting Point ◽  
The World ◽  
Development Goals ◽  
Short Essay ◽  
Public Environment

By browsing the website of Land Matrix, one can measure the extent of land-related large-scale investments in natural resources (LRINRs) and place it on the world map. At the time of writing, the extent of these investments covers an area equal to the surfaces of Spain and Portugal together – or, for football fans, around 60 million football pitches. These investment operations have often been saluted as instrumental to achieve the developmental needs of host countries and as the necessary private counterpart to state (and interstate) efforts aimed at (sustainable) development goals. Yet, the realities on the ground offer a scenario characterised by severe instances of displacement of indigenous or local communities and environmental disruptions. The starting point of this short essay is that these ‘externalities’ are generated through the legal construct enabling the implementation of these investment operations. As such, this contribution lies neatly in the line of research set forth in the excellent books of Kinnari Bhatt and Jennifer Lander, from the perspective of both the development culture shaping these investment operations and the private–public environment in which these are situated. The essay tries and dialogues with both components, while focusing at a metalevel on the theoretical shifts potentially geared to turn a ‘tale of exclusion’ into a ‘tale of inclusion’.

scholarly journals Chemical Modification as a Method of Improving Biocompatibility of Carbon Nonwovens

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3198
Author(s):  
Justyna Frączyk ◽  
Sylwia Magdziarz ◽  
Ewa Stodolak-Zych ◽  
Ewa Dzierzkowska ◽  
Dorota Puchowicz ◽  
...  
Keyword(s):  
Surface Modification ◽  
Cellular Response ◽  
Fiber Surface ◽  
Thermal Conversion ◽  
Cartilage Tissue ◽  
Polar Component ◽  
Nonwoven Fabrics ◽  
Biological Compatibility ◽  
Starting Point

It was shown that carbon nonwoven fabrics obtained from polyacrylonitrile fibers (PAN) by thermal conversion may be modified on the surface in order to improve their biological compatibility and cellular response, which is particularly important in the regeneration of bone or cartilage tissue. Surface functionalization of carbon nonwovens containing C–C double bonds was carried out using in situ generated diazonium salts derived from aromatic amines containing both electron-acceptor and electron-donor substituents. It was shown that the modification method characteristic for materials containing aromatic structures may be successfully applied to the functionalization of carbon materials. The effectiveness of the surface modification of carbon nonwoven fabrics was confirmed by the FTIR method using an ATR device. The proposed approach allows the incorporation of various functional groups on the nonwovens’ surface, which affects the morphology of fibers as well as their physicochemical properties (wettability). The introduction of a carboxyl group on the surface of nonwoven fabrics, in a reaction with 4-aminobenzoic acid, became a starting point for further modifications necessary for the attachment of RGD-type peptides facilitating cell adhesion to the surface of materials. The surface modification reduced the wettability (θ) of the carbon nonwoven by about 50%. The surface free energy (SFE) in the chemically modified and reference nonwovens remained similar, with the surface modification causing an increase in the polar component (ɣp). The modification of the fiber surface was heterogeneous in nature; however, it provided an attractive site of cell–materials interaction by contacting them to the fiber surface, which supports the adhesion process.

Development of ultrasonic methods for measuring in-situ stresses at great depth

1983 ◽  
Vol 1 (1) ◽  
pp. 21-42 ◽  
Author(s):  
W.H. Su ◽  
S.S. Peng ◽  
S. Okubo ◽  
K. Matsuki
Keyword(s):  
Great Depth ◽  
Ultrasonic Methods ◽  
In Situ Stresses

scholarly journals Metallic conduction through van der Waals interfaces in ultrathin $$\hbox{Bi}_2\hbox{Te}_3$$ films

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shinichiro Hatta ◽  
Ko Obayashi ◽  
Hiroshi Okuyama ◽  
Tetsuya Aruga
Keyword(s):  
Photoelectron Spectroscopy ◽  
Van Der Waals ◽  
Vertical Direction ◽  
Conductivity Measurement ◽  
Spatial Separation ◽  
Mean Free Path ◽  
Conduction Path ◽  
Conductivity Increase ◽  
The Impact

AbstractWhile the van der Waals (vdW) interface in layered materials hinders the transport of charge carriers in the vertical direction, it serves a good horizontal conduction path. We have investigated electrical conduction of few quintuple-layer (QL) $$\hbox {Bi}_2\hbox {Te}_3$$ Bi 2 Te 3 films by in situ four-point probe conductivity measurement. The impact of the vdW (Te–Te) interface appeared as a large conductivity increase with increasing thickness from 1 to 2 QL. Angle-resolved photoelectron spectroscopy and first-principles calculations reveal the confinement of bulk-like conduction band (CB) state into the vdW interface. Our analysis based on the Boltzmann equation showed that the conduction of the CB has a long mean free path compared to the surface-state conduction. This is mainly attributed to the spatial separation of the CB electrons and the donor defects located at the Bi sites.

The Strait of Magellan—a Gateway to New Worlds

2021 ◽  
Author(s):  
Mauricio Onetto Pavez
Keyword(s):  
Global Scale ◽  
Modern World ◽  
American Continent ◽  
The Earth ◽  
Starting Point ◽  
Strait Of Magellan ◽  
The World ◽  
The Strait Of Magellan ◽  
History Of ◽  
First Time

The year 2020 marks the five hundredth anniversary of the “discovery” of the Strait of Magellan. The unveiling of this passage between 1519 and 1522 allowed the planet to be circumnavigated for the first time in the history of humanity. All maritime routes could now be connected, and the idea of the Earth, in its geographical, cosmographic, and philosophical dimensions, gained its definitive meaning. This discovery can be considered one of the founding events of the modern world and of the process of globalization that still continues today. This new connectivity awoke an immediate interest in Europe that led to the emergence of a political consciousness of possession, domination, and territorial occupation generalized on a global scale, and the American continent was the starting point for this. This consciousness also inspired a desire for knowledge about this new form of inhabiting the world. Various fields of knowledge were redefined thanks to the new spaces and measurements produced by the discovery of the southern part of the Americas, which was recorded in books on cosmography, natural history, cartography, and manuscripts, circulating mainly between the Americas and Europe. All these processes transformed the Strait of Magellan into a geopolitical space coveted by Europeans during the 16th century. As an interoceanic connector, it was used to imagine commercial routes to the Orient and political projects that could sustain these dynamics. It was also conceived as a space to speculate on the potential wealth in the extreme south of the continent. In addition, on the Spanish side, some agents of the Crown considered it a strategic place for imperial projections and the defense of the Americas.

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