Corrigenda - The effects of gypsum on macroporosity and crusting of two red duplex soils

The effects of gypsum on the physical properties of two red duplex soils in northern Victoria were investigated by assessing the relative abundance of macropores (diameters greater than 75 �m) in the 0-30 mm zone of their cultivated layers. Samples were collected in October 1983 from both fallow cropped and stubble cropped plots. Changes in soil porosity between untreated and gypsum-treated plots were measured on photographic images of thin-sections using a Quantimet 720 image analyser. The soils differed in their clay mineralogy, one being dominated by illite, the other by randomly interstratified material. The results indicate only a minor improvement due to gypsum application in the area of macropores in the soils dominant in illite and kaolinite, whereas in the soil with the higher proportion of randomly interstratified clay minerals the area of macropores approximately doubled on the stubble cropped site and also considerably increased on the fallow cropped site. Micromorphological observations indicated that, in the presence of gypsum, crust formation was reduced because less clay was mobilized and redistributed in the surface soil layers.

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Petrography and provenance of the Marambio Group, Vega Island, Antarctica

Antarctic Science ◽

10.1017/s0954102094000775 ◽

1994 ◽

Vol 6 (4) ◽

pp. 517-527 ◽

Cited By ~ 12

Author(s):

Duncan Pirrie

Keyword(s):

Late Cretaceous ◽

Sedimentary Rocks ◽

Clay Mineralogy ◽

Minor Component ◽

Source Area ◽

Low Grade ◽

Western Margin ◽

Sediment Input ◽

A Minor ◽

Sandstone Petrography

Late Cretaceous sedimentary rocks assigned to the Santa Marta (Herbert Sound Member) and López de Bertodano (Cape Lamb and Sandwich Bluff members) formations of the Marambio Group, crop out on Cape Lamb, Vega Island. Although previous studies have recognized that these sedimentary rocks were derived from the northern Antarctic Peninsula region, the work presented here allows the provenance and palaeogeographical evolution of the region to be described in detail. On the basis of both sandstone petrography and clay mineralogy, the Herbert Sound and Cape Lamb members reflect sediment input from a low relief source area, with sand grade sediment sourced from low grade metasediments, and clay grade sediment ultimately derived from the weathering of an andesitic source area. In contrast, the Sandwich Bluff Member reflects a switch to a predominantly andesitic volcaniclastic source. However, this sediment was largely derived from older volcanic suites due to renewed source area uplift, with only a minor component from coeval volcanism. Regional uplift of both the arc terrane and the western margin of the James Ross Basin was likely during the Maastrichtian.

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Psychiatric illness, medication and driving: an audit of documentation

Irish Journal of Psychological Medicine ◽

10.1017/ipm.2015.31 ◽

2015 ◽

Vol 33 (3) ◽

pp. 171-174 ◽

Cited By ~ 1

Author(s):

A. Gallagher ◽

S. Shah ◽

W. Abassi ◽

E. Walsh

Keyword(s):

Road Safety ◽

Psychiatric Patients ◽

Fitness To Drive ◽

Team Members ◽

The Road ◽

Significant Difference ◽

New Guidelines ◽

A Minor ◽

Inpatient Psychiatric Unit ◽

Minor Improvement

ObjectivesGuidelines on advising patients on fitness to drive have been published recently by the Road Safety Authority in collaboration with the Royal College of Physicians of Ireland. The aim of this audit is to assess if the new guidelines are being adhered to.MethodExamination of the documentation and adherence to the guidelines in the inpatient psychiatric unit, Mayo General Hospital.ResultsOf the 100 patients included in audit cycle one, none had any specific documentation about driving. One patient was admitted with alcohol misuse and was driving. On re-auditing, following presentation at academic meeting and education of team members on the guidelines, there was a minor improvement of 7%.ConclusionThere was no significant difference in documentation on re-audit. However, an increase of 7% is nonetheless encouraging. Information concerning driving should be a standard part of advice given to all psychiatric patients.

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Mineralogical and Geochemical Trends in the Residual Soils above Basement Rocks in Ore Area, Southwestern Nigeria

Journal of Geography and Geology ◽

10.5539/jgg.v9n3p42 ◽

2017 ◽

Vol 9 (3) ◽

pp. 42

Author(s):

Adewole John Adeola ◽

Emmanuel Tamunobelema Tubonemi

Keyword(s):

Inductively Coupled Plasma ◽

Soil Layer ◽

Clay Mineralogy ◽

Lateritic Soil ◽

Residual Soils ◽

Southwestern Nigeria ◽

Thin Sections ◽

Tropical Regions ◽

Basement Rocks ◽

Parent Rocks

Residual clays and laterite of economic values often occur within weathering profiles above basement rocks in tropical regions due to supergene enrichment and leaching of liable components. Previous studies in Ore area mainly on geochemistry of the basement rocks with scanty information on the weathered profiles. This study was carried out to determine the compositional characteristics of the basement rocks, the geochemical trends within the profiles above the parent rocks and the evaluation of their economic potentials.Petrographic study was carried out on thin sections of the rock samples. Elemental compositions of the rocks, clay, laterite, and top-soil were determined using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Clay mineralogy was determined using X-ray Diffraction (XRD) analysis. Chemical index of Alterations (CIA) was calculated from geochemical data.Weathering of granite and banded gneiss in Ore resulted in the formation of soil layer, which ranged 0-0.5m, laterite 1.2-3m and clayey zone 2.9-3.0m. Quartz, plagioclase feldspars, microcline, biotite and hornblende were the essential minerals in the parent rocks. Granite and banded gneiss is high SiO2 (>65%) but low in MgO (<2.0%) and CaO (<4.0%). Kaolinite (60-80%), goethite (3-12%) and microcline (4-10%) were the dominant minerals in the XRD of the weathering profiles. Traces of illite were present only in granite. The CIA was generally > 85 indicating advanced state of weathering producing lateritic soil. The lateritic profiles over granite and banded gneiss of Ore area varied with the composition of the parent rocks. The clay layer has economic potential for ceramics, fertilizer and structural wares.

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Absorptive Routines and the Economic Impact of Incremental Innovations: Developing Continuous Improvement Strategies

Journal of Open Innovation Technology Market and Complexity ◽

10.3390/joitmc6040167 ◽

2020 ◽

Vol 6 (4) ◽

pp. 167

Author(s):

Rocío González-Sánchez ◽

Eva Pelechano-Barahona ◽

Sara Alonso-Muñoz ◽

Fernando E. García-Muiña

Keyword(s):

Specific Model ◽

Incremental Innovation ◽

Manufacturing Companies ◽

External Knowledge ◽

Continuous Innovation ◽

Complex Knowledge ◽

A Minor ◽

Relationship Of ◽

Synergistic Relationship ◽

Minor Improvement

The important influence that incremental innovation has, both on the organization’s results and on the development of disruptive innovations in a synergistic relationship of positive sum, makes it necessary to deepen its study. In the context of absorptive capacity, this paper aims to contribute to the construction of a specific model of routines for more efficient exploitation. The empirical study was carried out in a sample of Spanish manufacturing companies of the PITEC Panel. The results show the superiority of the market as a source of knowledge compared to other sources with more complex knowledge, but not adjusted to the needs of a minor improvement. In addition, the management of external knowledge is a process whose phases are interrelated, so the routines and resources used must contribute to enriching the external knowledge previously acquired and not be redundant. Therefore, that would mean an inefficient allocation of resources for obtaining and exploiting continuous innovation.

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Dynamic Effect of Input-Voltage Feedforward in Three-Phase Grid-Forming Inverters

Energies ◽

10.3390/en13112923 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2923

Author(s):

Matias Berg ◽

Tomi Roinila

Keyword(s):

Feedforward Control ◽

Dynamic Effect ◽

Input Voltage ◽

Input Admittance ◽

Proposed Model ◽

Three Phase ◽

Low Pass ◽

A Minor ◽

Element Theorem ◽

Minor Improvement

Grid-connected and grid-forming inverters play essential roles in the utilization of renewable energy. One problem of such a converter system is the voltage deviations in the DC-link between the source and the inverter that can disrupt the inverter output voltage. A common method to prevent these voltage deviations is to apply an input-voltage feedforward control. However, the feedforward control has detrimental effects on the inverter dynamics. It is shown that the effect of the feedforward in the input-to-output dynamics is not ideal due to the delay in the digital control system. The delay affects the input-to-output dynamics at high frequencies, and only a minor improvement can be achieved by low-pass filtering the feedforward control signal. Furthermore, the feedforward control can remarkably affect the inverter input admittance, and therefore, impedance-based stability problems may arise at the DC interface. This paper proposes a method based on linearization and extra element theorem to model the effect of the feedforward control in the inverter dynamics. Experimental measurements are shown to demonstrate the effectiveness of the proposed model.

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Seasonal and spatial variation of nitrogen dynamics in the litter and surface soil layers on a tropical dry evergreen forest slope

Forest Ecology and Management ◽

10.1016/j.foreco.2010.01.026 ◽

2010 ◽

Vol 259 (8) ◽

pp. 1502-1512 ◽

Cited By ~ 17

Author(s):

Naoyuki Yamashita ◽

Seiichi Ohta ◽

Hiroyuki Sase ◽

Jesada Luangjame ◽

Thiti Visaratana ◽

...

Keyword(s):

Spatial Variation ◽

Surface Soil ◽

Nitrogen Dynamics ◽

Evergreen Forest ◽

Soil Layers ◽

Dry Evergreen Forest ◽

Tropical Dry Evergreen Forest

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Effect of cementation on ultrasonic velocities in sandstones

Geophysics ◽

10.1190/1.2431327 ◽

2007 ◽

Vol 72 (2) ◽

pp. E53-E58 ◽

Cited By ~ 4

Author(s):

Ashraf M. Al-Tahini ◽

Carl H. Sondergeld ◽

Chandra S. Rai

Keyword(s):

Saudi Arabia ◽

Microstructural Analysis ◽

Acoustic Velocity ◽

Minor Role ◽

Point Counting ◽

Ultrasonic Velocities ◽

Thin Sections ◽

Acoustic Velocities ◽

A Minor

We determine the acoustic velocities for samples cored from the Jauf and Unayzah sandstone formations of Saudi Arabia. We use microstructural analysis including thin sections and point counting to quantify cementation. Velocities in these formations are strongly controlled by the combination of porosity and cementation. Consequently, rocks of similar porosity but with different cementation materials display different velocities. The objective of this study is to understand the effect of cementation on the acoustic velocity. Cements in these two formations have variable compositions and properties. Pure quartz overgrowth plays a major role in increasing velocities while clay and clay coatings play a minor role. We found that clay coatings inhibit the quartz overgrowth cement leading to a decrease in velocities. Understanding the influence of various cementation types on velocity, and thus elastic properties in sandstone cores, enables an understanding of the variation of sonic velocities and moduli across these formations. The uniqueness of this study is that we emphasize the quantification of the role of cement and not just mineral volume.

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Clay mineral distribution in the Devonian-Carboniferous sandstones of the Clair Field, west of Shetland, and its significance for reservoir quality

Clay Minerals ◽

10.1180/000985500546549 ◽

2000 ◽

Vol 35 (1) ◽

pp. 151-162 ◽

Cited By ~ 16

Author(s):

M. D. Pay ◽

T. R. Astin ◽

A. Parker

Keyword(s):

Clay Mineral ◽

Clay Mineralogy ◽

Reservoir Quality ◽

Pore Waters ◽

Aeolian Sediments ◽

Minor Influence ◽

Clay Coating ◽

Porosity And Permeability ◽

A Minor ◽

Pore Lining

AbstractThe Devonian-Carboniferous reservoir of the Clair Field contains a complex and variably abundant clay mineral assemblage. An abrupt vertical change in clay mineralogy has been observed in both wells studied (UKCS 206/8-7 and 206/8-8) from being rich in Mg-chlorite, chlorite- smectite (including dioctahedral corrensite), illite, illite-smectite and Fe-chlorite, to being smectite- rich. This change broadly coincides with the unconformable boundary between the Lower Clair Group and Upper Clair Group of the reservoir which possibly defines the Devonian-Carboniferous boundary. The clay minerals present reflect interaction between: (1) tectonic stability and climate that controlled the detrital composition of the sediment; (2) the pore-waters that developed; and (3) the result of diagenetic modification.Matrix porosity and permeability is severely restricted where the pore-lining clays are abundant (>15%) and where the clays bridge or fill pores. The type of clay mineral species appears to have a minor influence on reservoir quality, although they may be extremely important during production. The best reservoir quality occurs in mature aeolian sediments with a thin illite and illite-smectite clay coating.

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Characterization of partially purified microbodies from hydrocarbon-grown cells of Cladosporium resinae

Canadian Journal of Microbiology ◽

10.1139/m89-090 ◽

1989 ◽

Vol 35 (5) ◽

pp. 565-572 ◽

Cited By ~ 4

Author(s):

David B. Carson ◽

Joseph J. Cooney

Keyword(s):

Cytochrome C ◽

Cytochrome C Oxidase ◽

Density Gradient ◽

Gradient Centrifugation ◽

Urate Oxidase ◽

Marker Enzyme ◽

Thin Sections ◽

Cell Extracts ◽

Mitochondrial Fractions ◽

A Minor

Cells of the filamentous fungus Cladosporium resinae synthesize many more microbodies when they are grown on an n-alkane than when they are grown on glucose. Cladosporium resinae was grown on n-dodecane and spheroplasts were prepared, disrupted, and fractionated by differential and density gradient centrifugation. A fraction was isolated which was enriched in catalase, a marker enzyme for microbodies. Another fraction was isolated which was enriched in cytochrome c oxidase, a marker for mitochondria. Urate oxidase, a second marker for microbodies, was not detected in cell extracts. The microbody and mitochondrial fractions were relatively free of contamination from the endoplasmic reticulum and cytosol as indicated by the amounts of glucose-6-phosphatase and glucose-6-phosphate dehydrogenase present, respectively. Transmission electron microscopy revealed that the catalase-enriched fraction contained intact microbodies, with mitochondria as a minor contaminant. Catalase was localized in microbodies by staining with 3,3′-diaminobenzidine. Mitochrondria were present in the cytochrome c oxidase enriched fraction and took up the vital stain Janus green B. In similar preparations from cells grown on glucose, catalase was largely nonparticulate. Microbodies were not observed in thin sections prepared from density gradient fractions, but mitochondria were present in a cytochrome c oxidase enriched fraction.Key words: Cladosporium resinae, microbodies, mitochondria, catalase, cytochrome c oxidase.

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