scholarly journals Distinguishing the victim from the threat: SNP‐based methods reveal the extent of introgressive hybridization between wildcats and domestic cats in Scotland and inform future in situ and ex situ management options for species restoration

2018 ◽  
Vol 12 (3) ◽  
pp. 399-414 ◽  
Author(s):  
Helen V. Senn ◽  
Muhammad Ghazali ◽  
Jennifer Kaden ◽  
David Barclay ◽  
Ben Harrower ◽  
...  
Keyword(s):  
Introgressive Hybridization ◽  
Ex Situ ◽  
Domestic Cats ◽  
Management Options ◽  
Species Restoration ◽  
Ex Situ Management

scholarly journals Contaminants in Sediments - Remediation and Management

2013 ◽  
Vol 1 ◽  
pp. 02003
Author(s):  
A. S. Knox ◽  
M. H. Paller
Keyword(s):  
Organic Contaminants ◽  
Chemical Precipitation ◽  
Contaminated Sediments ◽  
Ex Situ ◽  
Sediment Surface ◽  
Management Options ◽  
Rock Phosphates ◽  
Precipitated Phase ◽  
Institutional Controls

Metals and organic contaminants are common in many marine and fresh water environments as a result of industrial and military activities. Traditional remediation/risk management options for sediments contaminated with these materials include no action, monitored natural recovery, institutional controls (land use restrictions, etc.), in situ treatment and management, and ex situ treatment and management. Active capping is a newer approach for treating contaminated sediments that involves applying chemically reactive amendments to the sediment surface. The mobile, soluble forms of contaminants are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This can be achieved through the application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active caps. Active caps can stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column thereby providing an economical and effective alternative to traditional treatments.

scholarly journals El preocupante estado de Centronia mutisii (Melastomataceae)

2011 ◽  
Vol 16 (3) ◽  
pp. 243
Author(s):  
Olga Adriana León ◽  
Camilo Esteban Cadena-Vargas ◽  
Mónica Saida Acosta-Ortiz
Keyword(s):  
Population Structure ◽  
Conservation Status ◽  
Decision Makers ◽  
Ex Situ ◽  
Conservation Strategies ◽  
Anthropogenic Pressure ◽  
Single Population ◽  
Threat Level ◽  
Ex Situ Management

<p><strong> </strong></p> <p><strong>Objective.</strong> Our study was intended to detail aspects of <em>Centronia mutisii </em>such as its distribution, population status and propagation, due to the anthropogenic pressure on its habitat which is restricted to a localized area in Cundinamarca and the District Capital, and because it is listed as a vulnerable species (VU) by the IUCN. <strong>Materials and methods.</strong> We identified the potential distribution of <em>C. </em><em>mutisii</em> (niche modeling), assessed the conservation status of the population, and applied plant propagation ex situ management treatments. <strong>Results.</strong> The potential geographic distribution is restricted and until now a single population has been recorded in a locality.  There is a marked edge effect on the population structure and propagation is difficult. <strong>Conclusions</strong>. We propose this species as a conservation priority due to its extremely localized distribution and population structure being affected by processes that affect its habitat, and also to begin a discussion on the reclassification of its current threat level. Decision makers should include <em>C. mutisii</em> in research and investment agendas to develop in situ and ex situ conservation strategies.</p> <p><strong>Key words: </strong>Sumapaz; IUCN; Maxent; Cundinamarca; Colombia</p> <p><strong> </strong></p> <p><strong></strong></p>

Fuel Yielding Species of Cold Desert Biosphere Reserve in the Indian Trans Himalaya

2017 ◽  
Vol 24 (1) ◽  
pp. 21-27
Author(s):  
Lipika Sharma ◽  
◽  
Sher Singh Samant ◽  
Ashish Kumar ◽  
◽  
...  
Keyword(s):  
Biosphere Reserve ◽  
Ex Situ ◽  
Fuel Wood ◽  
Management Options ◽  
Cold Desert ◽  
Tribal Communities ◽  
Local Resources ◽  
Fuel Resource ◽  
Preferred Species

Fuel is major source of domestic energy and depends upon the type of species available in the area. The tribal communities of Cold Desert Biosphere Reserve (CDBR) lead agro-pastoral lifestyle in which they heavily depend on local resources for fuel wood. The available studies indicated that comprehensive study on fuel resource is not available for the CDBR. Therefore, an attempt has been made to; (i) assess the diversity, distribution and utilization pattern of fuel resource; (ii) identify nativity and endemism of the fuel species; and (iii) suggest management options for conservation. The present study recorded 46 species of fuel representing trees (06 spp.), shrubs (37spp.) and herbs (03 spp.). Caprifoliaceae and Salicaceae (08 spp., each) were dominant families, and Lonicera (08 spp.) and Salix (07 spp.) were species rich genera. Maximum species were found in the 3000 ~ 4000 m zone. Amongst, fuel species, Caragana versicolor, Kracheninnikovia cerastoides, Lonicera spinosa and Salix spp. were the most preferred species from pastures for fuel wood. Only 22 species were native to the Himalayan region, 01 species i.e., Cotoneaster gilgitensis was endemic and 10 species were near endemic. Assessment of fuel species using ecological method (quadrat), study the extraction trends, develop conventional propagation protocols for mass multiplication and their establishment in the in-situ and ex-situ conditions, and create awareness among the tribal communities have been suggested.

An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

1988 ◽  
Vol 46 ◽  
pp. 884-885
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Defect Density ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Metal Base ◽  
In Situ Experiments ◽  
Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

The use of transmission and analytical electron microscopy in studying reactions and phase transformations in thin film

1993 ◽  
Vol 51 ◽  
pp. 842-843
Author(s):  
K. Barmak
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Phase Transformations ◽  
Analytical Electron Microscopy ◽  
Ex Situ ◽  
Multilayer Thin Films ◽  
Absolute Concentration ◽  
Analytical Electron ◽  
Deposition Step

Generally, processing of thin films involves several annealing steps in addition to the deposition step. During the annealing steps, diffusion, transformations and reactions take place. In this paper, examples of the use of TEM and AEM for ex situ and in situ studies of reactions and phase transformations in thin films will be presented.The ex situ studies were carried out on Nb/Al multilayer thin films annealed to different stages of reaction. Figure 1 shows a multilayer with dNb = 383 and dAl = 117 nm annealed at 750°C for 4 hours. As can be seen in the micrograph, there are four phases, Nb/Nb3-xAl/Nb2-xAl/NbAl3, present in the film at this stage of the reaction. The composition of each of the four regions marked 1-4 was obtained by EDX analysis. The absolute concentration in each region could not be determined due to the lack of thickness and geometry parameters that were required to make the necessary absorption and fluorescence corrections.

Transmission Electron Microscopy of Epitaxial silicides grown by ultra high vacuum deposition

1989 ◽  
Vol 47 ◽  
pp. 462-463
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Diffraction ◽  
High Vacuum ◽  
High Energy ◽  
Energy Electron ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Transmission Electron

The silicides CoSi2 and NiSi2 are both metallic with the fee flourite structure and lattice constants which are close to silicon (1.2% and 0.6% smaller at room temperature respectively) Consequently epitaxial cobalt and nickel disilicide can be grown on silicon. If these layers are formed by ultra high vacuum (UHV) deposition (also known as molecular beam epitaxy or MBE) their thickness can be controlled to within a few monolayers. Such ultrathin metal/silicon systems have many potential applications: for example electronic devices based on ballistic transport. They also provide a model system to study the properties of heterointerfaces. In this work we will discuss results obtained using in situ and ex situ transmission electron microscopy (TEM).In situ TEM is suited to the study of MBE growth for several reasons. It offers high spatial resolution and the ability to penetrate many monolayers of material. This is in contrast to the techniques which are usually employed for in situ measurements in MBE, for example low energy electron diffraction (LEED) and reflection high energy electron diffraction (RHEED), which are both sensitive to only a few monolayers at the surface.

Atomic Layer Deposition of LiF and Lithium Ion Conducting (AlF3)(LiF)x Alloys Using Trimethylaluminum, Lithium Hexamethyldisilazide and Hydrogen Fluoride

2017 ◽  
Author(s):  
Younghee Lee ◽  
Daniela M. Piper ◽  
Andrew S. Cavanagh ◽  
Matthias J. Young ◽  
Se-Hee Lee ◽  
...  
Keyword(s):  
Lithium Ion ◽  
Atomic Layer ◽  
Mass Gain ◽  
Alloy Film ◽  
Ex Situ ◽  
X Ray ◽  
Layer Deposition ◽  
Ion Conducting ◽  
Good Agreement

<div>Atomic layer deposition (ALD) of LiF and lithium ion conducting (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloys was developed using trimethylaluminum, lithium hexamethyldisilazide (LiHMDS) and hydrogen fluoride derived from HF-pyridine solution. ALD of LiF was studied using in situ quartz crystal microbalance (QCM) and in situ quadrupole mass spectrometer (QMS) at reaction temperatures between 125°C and 250°C. A mass gain per cycle of 12 ng/(cm<sup>2</sup> cycle) was obtained from QCM measurements at 150°C and decreased at higher temperatures. QMS detected FSi(CH<sub>3</sub>)<sub>3</sub> as a reaction byproduct instead of HMDS at 150°C. LiF ALD showed self-limiting behavior. Ex situ measurements using X-ray reflectivity (XRR) and spectroscopic ellipsometry (SE) showed a growth rate of 0.5-0.6 Å/cycle, in good agreement with the in situ QCM measurements.</div><div>ALD of lithium ion conducting (AlF3)(LiF)x alloys was also demonstrated using in situ QCM and in situ QMS at reaction temperatures at 150°C A mass gain per sequence of 22 ng/(cm<sup>2</sup> cycle) was obtained from QCM measurements at 150°C. Ex situ measurements using XRR and SE showed a linear growth rate of 0.9 Å/sequence, in good agreement with the in situ QCM measurements. Stoichiometry between AlF<sub>3</sub> and LiF by QCM experiment was calculated to 1:2.8. XPS showed LiF film consist of lithium and fluorine. XPS also showed (AlF<sub>3</sub>)(LiF)x alloy consists of aluminum, lithium and fluorine. Carbon, oxygen, and nitrogen impurities were both below the detection limit of XPS. Grazing incidence X-ray diffraction (GIXRD) observed that LiF and (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloy film have crystalline structures. Inductively coupled plasma mass spectrometry (ICP-MS) and ionic chromatography revealed atomic ratio of Li:F=1:1.1 and Al:Li:F=1:2.7: 5.4 for (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloy film. These atomic ratios were consistent with the calculation from QCM experiments. Finally, lithium ion conductivity (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloy film was measured as σ = 7.5 × 10<sup>-6</sup> S/cm.</div>

A New Method of Wafer Level Plan View TEM Sample Preparation by DualBeam

2008 ◽  
Author(s):  
Hyoung H. Kang ◽  
Michael A. Gribelyuk ◽  
Oliver D. Patterson ◽  
Steven B. Herschbein ◽  
Corey Senowitz
Keyword(s):  
Sample Preparation ◽  
Ex Situ ◽  
Wafer Level ◽  
Cross Sectional ◽  
Plan View ◽  
Manufacturing Line ◽  
Transmission Electron ◽  
Thin Lamella ◽  
Preparation Techniques

Abstract Cross-sectional style transmission electron microscopy (TEM) sample preparation techniques by DualBeam (SEM/FIB) systems are widely used in both laboratory and manufacturing lines with either in-situ or ex-situ lift out methods. By contrast, however, the plan view TEM sample has only been prepared in the laboratory environment, and only after breaking the wafer. This paper introduces a novel methodology for in-line, plan view TEM sample preparation at the 300mm wafer level that does not require breaking the wafer. It also presents the benefit of the technique on electrically short defects. The methodology of thin lamella TEM sample preparation for plan view work in two different tool configurations is also presented. The detailed procedure of thin lamella sample preparation is also described. In-line, full wafer plan view (S)TEM provides a quick turn around solution for defect analysis in the manufacturing line.

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