scholarly journals Studying the Earth with Geoneutrinos

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
L. Ludhova ◽  
S. Zavatarelli

Geoneutrinos, electron antineutrinos from natural radioactive decays inside the Earth, bring to the surface unique information about our planet. The new techniques in neutrino detection opened a door into a completely new interdisciplinary field of neutrino geoscience. We give here a broad geological introduction highlighting the points where the geoneutrino measurements can give substantial new insights. The status-of-art of this field is overviewed, including a description of the latest experimental results from KamLAND and Borexino experiments and their first geological implications. We performed a new combined Borexino and KamLAND analysis in terms of the extraction of the mantle geo-neutrino signal and the limits on the Earth's radiogenic heat power. The perspectives and the future projects having geo-neutrinos among their scientific goals are also discussed.

2012 ◽  
Vol 2012 ◽  
pp. 1-34 ◽  
Author(s):  
Ondřej Šrámek ◽  
William F. McDonough ◽  
John G. Learned

Neutrino geophysics is an emerging interdisciplinary field with the potential to map the abundances and distribution of radiogenic heat sources in the continental crust and deep Earth. To date, data from two different experiments quantify the amount of Th and U in the Earth and begin to put constraints on radiogenic power in the Earth available for driving mantle convection and plate tectonics. New improved detectors are under construction or in planning stages. Critical testing of compositional models of the Earth requires integrating geoneutrino and geological observations. Such tests will lead to significant constraints on the absolute and relative abundances of U and Th in the continents. High radioactivity in continental crust puts limits on land-based observatories' capacity to resolve mantle models with current detection methods. Multiple-site measurement in oceanic areas away from continental crust and nuclear reactors offers the best potential to extract mantle information. Geophysics would benefit from directional detection and the detectability of electron antineutrinos from potassium decay.


1978 ◽  
Vol 56 (10) ◽  
pp. 1261-1288 ◽  
Author(s):  
V. F. Sears

We present a review of the dynamical theory of neutron diffraction by macroscopic bodies which provides the theoretical basis for the study of neutron optics. We consider both the theory of dispersion, in which it is shown that the coherent wave in the medium satisfies a macroscopic one-body Schrödinger equation, and the theory of reflection, refraction, and diffraction in which the above equation is solved for a number of special cases of interest. The theory is illustrated with the help of experimental results obtained over the past 10 years by a number of new techniques such as neutron gravity refractometry, Pendellösung interference, and neutron interferometry.


1985 ◽  
Vol 38 (02) ◽  
pp. 216-217
Author(s):  
G. A. Wilkins

New techniques of measurement make it possible in 1984 to determine positions on the surface of the Earth to a much higher precision than was possible in 1884. If we look beyond the requirements of navigation we can see useful applications of global geodetic positioning to centimetric accuracy for such purposes as the control of mapping and the study of crustal movements. These new techniques depend upon observations of external objects, such as satellites or quasars rather than stars, and they require that the positions of these objects and the orientation of the surface of the Earth are both known with respect to an appropriate external reference system that is ‘fixed’ in space. We need networks of observing stations and analysis centres that monitor the motions of the external objects and the rotation of the Earth. Observations of stars by a transit circle are no longer adequate for this purpose.


1988 ◽  
Vol 25 (8) ◽  
pp. 1199-1208 ◽  
Author(s):  
J. Tuzo Wilson

Until a little more than a century ago the land surface not only was the only part of the Earth accessible to humans but also was the only part for which geophysical and geochemical methods could then provide any details. Since then scientists have developed ways to study the ocean floors and some details of the interior of the Earth to ever greater depths. These discoveries have followed one another more and more rapidly, and now results have been obtained from all depths of the Earth.New methods have not contradicted or greatly disturbed either old methods or old results. Hence, it has been easy to overlook the great importance of these recent findings.Within about the last 5 years the new techniques have mapped the pattern of convection currents in the mantle and shown that these rise from great depths to the surface. Even though the results are still incomplete and are the subject of debate, enough is known to show that the convection currents take two quite different modes. One of these breaks the strong lithosphere; the other moves surface fragments and plates about.It is pointed out that if expanding mid-ocean ridges move continents and plates, geometrical considerations demand that the expanding ridges must themselves migrate. Hence, collisions between ridges and plates are likely to have occurred often during geological time.Twenty years ago it was shown that the effect of a "mid-ocean ridge in the mouth of the Gulf of Aden" was to enter and rift the continent. This paper points out some of the conditions under which such collisions occur and in particular shows that the angle of incidence between a ridge and a coastline has important consequences upon the result. Several past and present cases are used to illustrate that collisions at right angles tend to produce rifting; collisions at oblique angles appear to terminate in the lithosphere in coastal shears, creating displaced terrane, but in the mantle the upward flow may continue to uplift the lithosphere far inland and produce important surface effects; collisions between coasts and mid-ocean ridges parallel to them produce hot uplifts moving inland. For a time these upwellings push thrusts and folds ahead of them, but they appear to die down before reaching cratons.


2018 ◽  
Author(s):  
Peter M. Shane

This paper examines the status of debates concerning the constitutionality of private suits to enforce civil fines in light of the Supreme Court's decisions in Vermont Agency of Natural Resources v. United States ex rel. Stevens and Friends of the Earth v. Laidlaw Environmental Services, as well as a pending Fifth Circuit decision in United States ex rel. Riley v. St. Luke's Episcopal Hospital. The two Supreme Court opinions have upheld qui tam and citizen suits against standing challenges, but have reserved the question of their constitutionality under Article II. The Riley panel opinion held qui tam actions to be unconstitutional under Article II, but the Fifth Circuit took the matter en banc on its own motion on the very day the opinion was published. (Subsequent to the publication of this article, the Fifth Circuit overturned the panel opinion and upheld the constitutionality of qui tam actions, Riley v. St. Luke's Episcopal Hosp., 252 F.3d 749 (5th Cir. 2001).) In the author's judgment, all such private suits to enforce civil fines are plainly constitutional under both Article II and Article III. That such suits appear to raise constitutional doubts is the consequence of missteps in the Supreme Court's implementation of separation of powers principles. The Court, led chiefly in this respect by Justice Scalia, has written often as if constitutionally vested executive authority guarantees the President plenary policy control over all federal civil administration, and as if the purpose of standing doctrine were largely to protect such executive authority from judicial interference. The author believes that the vesting of executive power is better understood as an effort to remove Congress from the business of administration. Standing rules, for their part, ought chiefly to be understood as protecting the judiciary from the dilution of judicial power that would come from the resolution of abstract or collusive litigation. The author explains why the Court should go back to requiring no more as a matter of standing doctrine than that a case be presented in an adversary context and in a manner historically viewed as capable of judicial resolution. The Court's injury, causality, and redressability inquiries should be abandoned in favor of a more straightforward questioning whether plaintiffs in federal lawsuits have constitutional or statutory causes of action to support their complaints. In Article II cases, the Court should adhere to the analytic framework of Morrison v. Olson, and abandon the more wooden and categorical approach to interpreting executive power that informs Justice Scalia's Morrison dissent and his alternative holding in Printz v. United States.


2020 ◽  
Vol 214 ◽  
pp. 01038
Author(s):  
Lihao Sun ◽  
Yuxiang Shen

As people’s living standards continue to ameliorate, people become more and more demanding of the status of eco-environment, and carbon emissions are a key factor affecting the eco-environment. We analyze the carbon emissions intensity and carbon emissions potential of different sectors in China based on the input-output model. The results show that the sector of Production and Supply of Electric Power and Heat Power has the highest embodied carbon emissions intensity because the sector provides the country with necessary electricity and heat power for its economic growth. In addition, this paper determines the key carbon emissions sectors using elasticity method, and the results show that Construction is the most influential carbon emissions sector in the future. By restricting key carbon emissions sectors and encouraging the non-key carbon emissions sectors, we can take into account both economic development and carbon emissions reduction with the multi-objective model. The results show that under the present economic scale of China, carbon emissions can decrease from 11591 million ton to 11011 million ton, with a difference of 580 million ton. This indicates that with the assurance of present economic growth, we can achieve the goal of reducing carbon emissions by adjusting the economic structure. Based on results of this paper, we have also made recommendations for adjusting the economic structure to achieve emission reduction targets.


Adam alemi ◽  
2021 ◽  
Vol 90 (4) ◽  
pp. 123-132
Author(s):  
R. Akhmaganbetov ◽  

The land conflict has long been a type of actual conflict. There are land conflicts of various levels in Kazakhstan. There are different points of view related to the land conflict. There are many prerequisites for the emergence of these views. The study examined the views of representatives of various political and philosophical trends related to the status of the earth. Representatives of the liberal trend consider land as capital. The analysis of the works of representatives of the liberal movement considering land as capital is carried out. Representatives of the socialist trend consider land as state property. Lenin's works deal with issues related to the resolution of the land conflict. Representatives of postcolonialism explain the emergence of the earthly conflict by the influence of colonial empires. In connection with the land conflict, the positions of the Alash intelligentsia are considered. Meanwhile, the analysis of differences in the views of socialists and the Alash intelligentsia in resolving the land conflict was carried out. In traditional Kazakh society, land is considered as a value. This is not consistent with the concepts of capital or property. The earth is considered as a sacred concept. A comparative analysis of such different points of view is carried out. The historical prerequisites for the emergence of a land conflict at the present time are considered.


2019 ◽  
Vol 67 (S5) ◽  
pp. S70-S80
Author(s):  
Rodolfo Elías ◽  
María Andrea Saracho-Bottero ◽  
Carol Anne Simon

Introduction: The knowledge of polychaetes in the subtropical region of Africa benefited from the activity of J. Day. However, 50 years after the publication of his Monograph of the Polychaeta of southern Africa, it is necessary to reconsider the identity of the Cirratulidae due to changes in the diagnostic characters and new approaches to the taxonomy of the group to corroborate the status of cosmopolitan species in this region. Objective: We hypothesize that biodiversity of multitentacular Cirratulidae polychaetes has been significantly underestimated in southern Africa. Methods: The present work analyzes material deposited in the Iziko museum, as well as recently collected specimens, using scanning electron microscope to identify them. Results: The material corresponds to two new species belonging to the genus Protocirrineris. Protocirrineris strandloperarum sp. nov. is characterized by having the tentacular filaments between the chaetigers 5 to 10-12 and the first pair of branchiae from chaetiger 7, and P. magalhaesi sp. nov. is characterized by having tentacular filaments between chaetigers 4-8 and the first pair of branchiae from chaetigers 2 or 3. Descriptions of these species, with light and scanning electron microscope images, are given. Schematic drawings of the two new species are shown comparatively with diagnostic characters. Conclusions: The use of new techniques enables discovery of new taxonomic characters and two new species of the genus. The diversity of Cirratulidae polychaetes is underestimated also in the subtropical and tropical regions of Africa.


2011 ◽  
Vol 346 ◽  
pp. 731-737 ◽  
Author(s):  
Jin Feng Yang ◽  
Man Hua Liu ◽  
Hui Zhao ◽  
Wei Tao

This paper presents an efficient method to detect the fastener based on the technologies of image processing and optical detection. As feature descriptor, the Direction Field of fastener image is computed for template matching. This fastener detection method can be used to determine the status of fastener on the corresponding track, i.e., whether the fastener is on the track or missing. Experimental results are presented to show that the proposed method is computation efficiency and is robust for fastener detection in complex environment.


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