scholarly journals Predatory Ants: First Report on Direct Evidence of Predation by Dorylus orientalis Westwood, 1885 on Olive Ridley Eggs from India

2020 ◽  
Author(s):  
Sumedha Korgaonkar ◽  
Anuja Vartak ◽  
Kuppusamy Sivakumar
Keyword(s):  
Direct Evidence ◽  
Ex Situ ◽  
Olive Ridley ◽  
Lepidochelys Olivacea ◽  
Ant Predation ◽  
Nesting Site ◽  
Feral Dogs ◽  
Natural Pesticide ◽  
Predatory Ants

Abstract: Predation of eggs and emerging hatchlings of olive ridley turtle (Lepidochelys olivacea) by wild animals and feral dogs are known. They reduce the hatching success rate considerably affecting the conservation management of this vulnerable species. Hatchery management is practised in India to overcome predation. Ant predation is a serious threat to turtle nest protected by ex situ or in situ erected hatchery. This article reports the first direct evidence of turtle eggs predation by Dorylus orientalis Westwood, 1835 commonly called red ants. Native to India, Oriental, Indo Australian and Palearctic regions they are notorious as an agricultural pest. Chlorpyrifos pesticides recommended for their control could become fatal for the developing embryos of turtles if applied near the hatchery. In the turtle nesting site of the west coast of India, D. orientalis has more of an ecological role than as a pest. Natural pesticide such as Neem powder (Azadirachta indica) shows promising results for preventing their infestation.

scholarly journals Direct Evidence of Cobalt Oxyhydroxide Formation on a La0.2Sr0.8CoO3 Perovskite Water Splitting Catalyst

2021 ◽  
Author(s):  
Anthony Boucly ◽  
Luca Artiglia ◽  
Emiliana Fabbri ◽  
Dennis Palagin ◽  
Dino Aergerter ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Active Sites ◽  
Direct Evidence ◽  
Ambient Pressure ◽  
Spectral Feature ◽  
Ex Situ ◽  
Oxide Surface ◽  
Catalytic Systems ◽  
Cobalt Oxyhydroxide

Abstract Understanding the mechanism of oxygen evolution reaction (OER) on perovskite materials is of great interest to tailor the synthesis of better catalyst materials. Despite the huge amount of literature reports, the complexity of catalytic systems and scarce in situ and operando surface sensitive spectroscopic tools render the detection of active sites and the understanding of the reaction mechanisms challenging. Here, we carried out and compared in situ and ex situ ambient pressure X-ray photoelectron spectroscopy experimental procedures on a La0.2Sr0.8CoO3 perovskite OER catalyst. Experimental results show that segregated surface strontium, which is present in the as prepared sample, is leached into the electrolyte after immersion, leading to surface cobalt active sites enrichment. Such cobalt-enriched oxide surface evolves into a new phase, whose spectral feature is detected in situ, during/after OER. With the help of theoretical simulations, such species is assigned to cobalt oxyhydroxide, providing a direct evidence of its crucial role in the reaction.

scholarly journals Investigating Processes of Nanocrystal Formation and Transformation via Liquid Cell TEM

2014 ◽  
Vol 20 (2) ◽  
pp. 425-436 ◽  
Author(s):  
Michael H. Nielsen ◽  
Dongsheng Li ◽  
Hengzhong Zhang ◽  
Shaul Aloni ◽  
T. Yong-Jin Han ◽  
...  
Keyword(s):  
Direct Evidence ◽  
Nucleation And Growth ◽  
Ex Situ ◽  
Bulk Solution ◽  
Dynamic Information ◽  
Transmission Electron ◽  
Classical Models ◽  
Liquid Cell ◽  
Temporal And Spatial

AbstractRecent ex situ observations of crystallization in both natural and synthetic systems indicate that the classical models of nucleation and growth are inaccurate. However, in situ observations that can provide direct evidence for alternative models have been lacking due to the limited temporal and spatial resolution of experimental techniques that can observe dynamic processes in a bulk solution. Here we report results from liquid cell transmission electron microscopy studies of nucleation and growth of Au, CaCO3, and iron oxide nanoparticles. We show how these in situ data can be used to obtain direct evidence for the mechanisms underlying nanoparticle crystallization as well as dynamic information that provide constraints on important energetic parameters not available through ex situ methods.

scholarly journals Neonate survival en handled broods of the Olive Ridley Turtle Lepidochelys olivacea (Testudines: Cheloniidae) in “El Verde”, Sinaloa, Mexico

2013 ◽  
Vol 5 (1) ◽  
pp. 137-141
Author(s):  
Luis A. Rendón ◽  
Armando A. Ortega-Salas
Keyword(s):  
Protected Area ◽  
Olive Ridley ◽  
Conservation Area ◽  
Lepidochelys Olivacea ◽  
Nesting Site ◽  
Olive Ridley Turtle

We worked in the protective and conservation area of the Olive Ridley Turtle Lepidochelys olivacea in the beaches of Estero Verde, Sinaloa, Mexico (2004 season). The position in the beach does not affect survival. We found nests until the preferential nesting site located at the beginning of the second sandy berm in a zone free of vegetation; and the latter presented a slight increase in survival. Specimens handled for 2-5 hours survived less (R2=0,82). KEY WORDSIncidence of turtles, management, survival, protected area, conservation. 

scholarly journals Sosialisasi Konservasi Penyu Laut Berbasis Edukasi di SMPN 1 Desa Keude Panga Kecamatan Panga Kabupaten Aceh Jaya Provinsi Aceh

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Mohamad Gazali ◽  
Supriadi Supriadi ◽  
Masyumi Masyumi ◽  
Irham Dika
Keyword(s):  
Junior High School ◽  
Sea Turtle ◽  
Dermochelys Coriacea ◽  
Young Generation ◽  
Olive Ridley ◽  
Lepidochelys Olivacea ◽  
Turtle Conservation ◽  
Nesting Site ◽  
Sea Turtle Conservation ◽  
Leatherback Sea Turtle

According to observation and interview that undertaken in Panga District Aceh Jaya Regency that there are 3 species of sea turtle with coastal line is 9.3. km. The third of such sea turtle including Olive ridley sea turtle(Lepidochelys  olivacea), hawkbill sea turtle (Eremochelys imbricate), leatherback sea turtle (Dermochelys coriacea). The target of community that involved in socialization of sea turtle are student  of junior high school. Earlier education to young generation  regarding the important of sea turtle conservation educated-based is the effort for keeping sea turtle in natural with undertook the socialization to young generation in order to grow a caring and loving to sea turtle sustainablity. Coastal community still undertook to hunting sea turtle’s eggs for trading in the traditional market dan restaurants. It is caused by lack of understanding and awareness regarding sea turtle that threaten scarce. In this activity, the researcher will undertake persuasive approaach and solutive in changing a mindset of young generation gradually that inhabit in near nesting site. In this activity including suvey activity prior to socialization that near the nesting site, socialization activity in the SMPN 1 Panga that selected as target school in the socialization of Sea Turtle Conservation, conducting the retelling story games, and conducting hatchlings release programme to the sea with community elements.

Evidence for Substitutional C, Ordering Effects and Interdiffusion in Epitaxial GE-C and GE-RICH GE-SI-C Alloys

1998 ◽  
Vol 533 ◽  
Author(s):  
Bi-Ke Yang ◽  
W. H. Weber ◽  
M. Krishnamurthy
Keyword(s):  
Raman Spectroscopy ◽  
Direct Evidence ◽  
Ex Situ ◽  
Local Mode ◽  
Simple Diffusion ◽  
Ordering Effects ◽  
Transmission Electron ◽  
Enhanced Solubility ◽  
Simple Diffusion Model

AbstractWe report on the epitaxial growth of Ge-C and Ge-Si-C alloys (C<10%) grown on Si(100) and Ge(100) substrates using low temperature (∼200°C) molecular beam epitaxy. Thin films (50–70 nm) were characterized in-situ by RHEED and ex-situ by transmission electron microscopy, xray diffraction, and Raman spectroscopy. The films were annealed at 750°C and 850°C in an Ar atmosphere to study interdiffusion effects.Raman spectroscopy of Ge-C on Ge indicates the existence of a Ge-C local mode at 530cm−1 and is direct evidence for the presence of substitutional C in Ge. The GeSiC alloys grown on Ge do not show the Ge-C local mode, consistent with preferential Si-C bonding. There is evidence for strain enhanced solubility of C based on a comparison of the substitutional C content in Ge-C films on Si (∼1 at %) and on Ge substrates (∼0.1 at %). Silicon interdiffusion in annealed Ge-C samples is strongly suppressed by the presence of C. A simple diffusion model is used to illustrate Si indiffusion in Ge.

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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