THE SEPARATION OF REMANENT FROM INDUCED MAGNETISM IN SITU

Geophysics ◽  
1966 ◽  
Vol 31 (4) ◽  
pp. 779-796 ◽  
Author(s):  
N. E. Goldstein ◽  
S. H. Ward
Keyword(s):  
Magnetic Anomaly ◽  
Field Experiments ◽  
Magnetic Anomalies ◽  
Static Field ◽  
Observational Evidence ◽  
Field Direction ◽  
Dynamic Field ◽  
In Situ Separation

Remanent and induced magnetism both contribute to static field magnetic anomalies whereas only induced magnetism contributes to dynamic field magnetic anomalies. The theory whereby this phenomenon may be used to advantage for in‐situ separation of remanent from induced magnetism is presented as a prelude to observational evidence confirming the phenomenon. Four field experiments on Western States magnetic anomalies prove that it is possible to predict whether or not a given static field magnetic anomaly is primarily due to remanent or to induced magnetism. The limitations of the method include variability of micropulsation field direction, ellipticity, and intensity.

TiO2/sulfonated graphene oxide/Ag nanoparticle membrane: In situ separation and photodegradation of oil/water emulsions

2018 ◽  
Vol 554 ◽  
pp. 16-25 ◽  
Author(s):  
Dongliang Qian ◽  
Dongyun Chen ◽  
Najun Li ◽  
Qingfeng Xu ◽  
Hua Li ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Ag Nanoparticle ◽  
Sulfonated Graphene ◽  
In Situ Separation ◽  
Oil Water

scholarly journals Microbial Functional Gene Diversity with a Shift of Subsurface Redox Conditions duringIn SituUranium Reduction

2012 ◽  
Vol 78 (8) ◽  
pp. 2966-2972 ◽  
Author(s):  
Yuting Liang ◽  
Joy D. Van Nostrand ◽  
Lucie A. N′Guessan ◽  
Aaron D. Peacock ◽  
Ye Deng ◽  
...  
Keyword(s):  
Functional Diversity ◽  
Field Experiments ◽  
Gene Diversity ◽  
Functional Gene ◽  
Redox Conditions ◽  
Functional Genes ◽  
Microbial Functional Diversity ◽  
Content Type ◽  
Microbial Functional Gene

ABSTRACTTo better understand the microbial functional diversity changes with subsurface redox conditions duringin situuranium bioremediation, key functional genes were studied with GeoChip, a comprehensive functional gene microarray, in field experiments at a uranium mill tailings remedial action (UMTRA) site (Rifle, CO). The results indicated that functional microbial communities altered with a shift in the dominant metabolic process, as documented by hierarchical cluster and ordination analyses of all detected functional genes. The abundance ofdsrABgenes (dissimilatory sulfite reductase genes) and methane generation-relatedmcrgenes (methyl coenzyme M reductase coding genes) increased when redox conditions shifted from Fe-reducing to sulfate-reducing conditions. The cytochrome genes detected were primarily fromGeobactersp. and decreased with lower subsurface redox conditions. Statistical analysis of environmental parameters and functional genes indicated that acetate, U(VI), and redox potential (Eh) were the most significant geochemical variables linked to microbial functional gene structures, and changes in microbial functional diversity were strongly related to the dominant terminal electron-accepting process following acetate addition. The study indicates that the microbial functional genes clearly reflect thein situredox conditions and the dominant microbial processes, which in turn influence uranium bioreduction. Microbial functional genes thus could be very useful for tracking microbial community structure and dynamics during bioremediation.

CO2 Capture Using Calcium Oxide Applicable to In-Situ Separation of CO2 From H2 Production Processes

2013 ◽  
Author(s):  
Saeed Danaei Kenarsari ◽  
Yuan Zheng
Keyword(s):  
Calcium Oxide ◽  
Co2 Capture ◽  
Fixed Bed ◽  
H2 Production ◽  
Fixed Bed Reactor ◽  
Capture Process ◽  
Conversion Rates ◽  
In Situ Separation ◽  
Separation Of Co2

A lab-scale CO2 capture system is designed, fabricated, and tested for performing CO2 capture via carbonation of very fine calcium oxide (CaO) with particle size in micrometers. This system includes a fixed-bed reactor made of stainless steel (12.7 mm in diameter and 76.2 mm long) packed with calcium oxide particles dispersed in sand particles; heated and maintained at a certain temperature (500–550°C) during each experiment. The pressure along the reactor can be kept constant using a back pressure regulator. The conditions of the tests are relevant to separation of CO2 from combustion/gasification flue gases and in-situ CO2 capture process. The inlet flow, 1% CO2 and 99% N2, goes through the reactor at the flow rate of 150 mL/min (at standard conditions). The CO2 percentage of the outlet gas is monitored and recorded by a portable CO2 analyzer. Using the outlet composition, the conversion of calcium oxide is figured and employed to develop the kinetics model. The results indicate that the rates of carbonation reactions considerably increase with raising the temperature from 500°C to 550°C. The conversion rates of CaO-carbonation are well fitted to a shrinking core model which combines chemical reaction controlled and diffusion controlled models.

scholarly journals A High-Accuracy Multiwavelength Radiometer for In Situ Measurements in the Thermal Infrared. Part II: Behavior in Field Experiments

2003 ◽  
Vol 20 (7) ◽  
pp. 1023-1033 ◽  
Author(s):  
Gérard Brogniez ◽  
Christophe Pietras ◽  
Michel Legrand ◽  
Philippe Dubuisson ◽  
Martial Haeffelin
Keyword(s):  
Field Experiments ◽  
Thermal Infrared ◽  
High Accuracy ◽  
In Situ Measurements

Enzymatic production and in situ separation of natural β-ionone from β-carotene

2012 ◽  
Vol 39 (12) ◽  
pp. 1771-1778 ◽  
Author(s):  
Christoph Nacke ◽  
Sonja Hüttmann ◽  
Maria M. W. Etschmann ◽  
Jens Schrader
Keyword(s):  
Enzymatic Production ◽  
In Situ Separation ◽  
Β Carotene

Colonization of depopulated crinoids by symbionts: who comes from the bottom and who from the water column?

2015 ◽  
Vol 95 (8) ◽  
pp. 1607-1612 ◽  
Author(s):  
E.S. Mekhova ◽  
P.Y. Dgebuadze ◽  
V.N. Mikheev ◽  
T.A. Britayev
Keyword(s):  
Water Column ◽  
Field Experiments ◽  
Dispersal Ability ◽  
Long Distance ◽  
Sandy Substrate ◽  
Limited Dispersal ◽  
Set Up ◽  
Almost All ◽  
High Degree

Previous experiments with the comatulid Himerometra robustipinna (Carpenter, 1881) demonstrated intensive host-to-host migration processes for almost all symbiotic species both within host aggregations and among hosts separated by several metres. The aim of this study was to check the ability of symbionts to complete long-distance migrations, by means of two in situ experiments which depopulated the crinoid host. Two different sets of field experiments were set up: exposure of depopulated crinoids (set 1) on stony ‘islands’ isolated from native crinoid assemblages by sandy substrate, and (set 2) in cages suspended in the water column. Hosts from set 1 were exposed for 1, 2, 3 and 4 weeks to assess whether substrate has an influence on the symbionts' long-distance migrations. In set 2 cages were exposed for 10–11 days, aiming to check whether symbionts were able to disperse through the water column with currents. These experiments allow the conclusion that post-settled symbionts can actively migrate among their hosts. Symbionts are able to reach their hosts by employing two different ‘transport corridors’, by drifting or swimming in water column, and by moving on the bottom. Comparison of experimental results allows the division of symbionts into two conventional groups according to the dispersal ability of their post-settled stages: (1) species able to complete long-distance migrations, (2) species unable to migrate or having limited dispersal ability. The finding of the free-living shrimp Periclimenes diversipes Kemp, 1922 in set 2 raises the question about the factors that affect such a high degree of specialization of crinoid assemblages.

Analysis of Magnetic Anomaly Characteristics of Underground Non-Coplanar Cross-buried Iron Pipelines

2020 ◽  
Vol 25 (2) ◽  
pp. 223-233
Author(s):  
Pan Wu ◽  
Minghui Wei
Keyword(s):  
Magnetic Susceptibility ◽  
Magnetic Anomaly ◽  
Magnetic Dipole ◽  
Geomagnetic Field ◽  
Magnetic Anomalies ◽  
Buried Pipelines ◽  
Magnetic Declination ◽  
Magnetic Inclination ◽  
Basic Characteristics ◽  
Geomagnetic Intensity

The non-coplanar cross-buried pipelines are a common way of pipeline wiring. In order to investigate the magnetic anomaly characteristics of the non-coplanar cross-buried pipelines and guide the site operation, the influences of a series of factors on the magnetic anomaly of the non-coplanar cross-buried pipelines are analyzed. Based on the principle of magnetic dipole construction, a forward model is established for the magnetic anomaly characteristics of the subsurface non-coplanar cross-buried pipelines. The basic characteristics of magnetic anomaly for the non-coplanar cross-buried pipelines are defined. The influences of geomagnetic parameters (geomagnetic intensity, geomagnetic inclination, and geomagnetic declination), pipeline parameters (thickness, magnetic susceptibility), and cross angle of pipelines on the characteristics of magnetic anomalies are analyzed. The results show that the shape of the total magnetic anomaly is mainly affected by the magnetic inclination, and the curve of magnetic anomaly at ± I site shows some symmetry. The amplitude is approximately linearly affected by the total geomagnetic field, magnetic declination, pipeline thickness, material magnetic susceptibility, and pipeline cross angle. There is a periodic change of the amplitude with the increase of geomagnetic inclination (−90°–>90°). The crest-trough distance is mainly affected by geomagnetic inclination, magnetic declination, thickness, magnetic susceptibility, and pipeline cross angle. A more accurate measurement can be achieved if the direction of the pipelines is roughly measured and then the number of measurement points is augmented near the intersection of pipelines and the measurement lines. Present work obtains the equivalent magnetic dipole units by segmenting pipelines. The magnetic anomaly characteristics of non-coplanar crossed iron pipelines are successfully simulated. The numerical results are in accordance with the experimental analysis.

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