AFM Analysis of ECR Dry-Etched Ingap, Alinp and Algap

1995 ◽  
Vol 406 ◽  
Author(s):  
F. Ren ◽  
W. S. Hobson ◽  
J. R. Lothian ◽  
J. Lopata ◽  
J. A. Caballero ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Microwave Power ◽  
Binary Component ◽  
Wide Range ◽  
Afm Analysis ◽  
The Common ◽  
Etch Rates ◽  
Surface Morphologies

AbstractThe etch rates of InGaP, AlInP and AlGaP increases dramatically with microwave power in ECR BCl3- or CH4/H2-based discharges, reaching values near 1μm·min−1 at 1000W, The surface morphologies of these materials however behave much differently as the microwave power is increased. For BCl3 etching of InGaP the surface RMS roughness decreases from 36nm at 250W to 2nm at 1000W. For AlInP, there is little change in surface morphology, whereas for the common binary component of these two materials, InP, the surface becomes very rough at high powers (>60nm RMS). By contrast, the morphologies of the three ternaries remain smooth over a wide range of conditions with CH4/H2/Ar. The AFM analysis, coupled with AES enables us to understand these different responses in terms of volatility of the respective chloride, metalorganic and hydride etch products.

High Rate Dry Etching of GaN, AIN and InN in ECR Cl2/CH4/H2/Ar Plasmas

1995 ◽  
Vol 380 ◽  
Author(s):  
C. B. Vartuli ◽  
S. J. Pearton ◽  
C. R. Abernathy ◽  
R. J. Shul ◽  
S. P. Kilcoyne ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Microwave Power ◽  
Etch Rate ◽  
Surface Composition ◽  
Plasma Chemistry ◽  
High Rate ◽  
Rf Power ◽  
Plasma Parameters ◽  
Wide Range ◽  
Etch Rates

ABSTRACTEtch rates for binary nitrides in ECR Cl2/CH4/H2/Ar are reported as a function of temperature, rf-bias, microwave power, pressure and relative gas proportions. GaN etch rates remain relatively constant from 30 to 125 °C and then increase to a maximum of 2340 Å-min−1 at 170 °C. The AIN etch rate decreases throughout the temperature range studied with a maximum of 960 Å-min−1 at 30 °C. When CH4 is removed from the plasma chemistry, the GaN and InN etch rates are slightly lower, with less dramatic changes with temperature. The surface composition of the III–V nitrides remains unchanged over the temperatures studied. The GaN and InN rates increase significantly with rf power, and the fastest rates for all three binaries are obtained at 2 mTorr. Surface morphology is smooth for GaN over a wide range of conditions, whereas InN surfaces are more sensitive to plasma parameters.

Defect morphology in thick relaxed layers of InGaAs on GaAs

1990 ◽  
Vol 48 (4) ◽  
pp. 668-669
Author(s):  
R H Dixon ◽  
P Kidd ◽  
P J Goodhew
Keyword(s):  
Electron Microscopy ◽  
Surface Morphology ◽  
Growth Conditions ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
Strained Layers ◽  
Good Surface ◽  
Transmission Electron ◽  
Device Structures ◽  
Surface Morphologies

Thick relaxed InGaAs layers grown epitaxially on GaAs are potentially useful substrates for growing high indium percentage strained layers. It is important that these relaxed layers are defect free and have a good surface morphology for the subsequent growth of device structures.3μm relaxed layers of InxGa1-xAs were grown on semi - insulating GaAs substrates by Molecular Beam Epitaxy (MBE), where the indium composition ranged from x=0.1 to 1.0. The interface, bulk and surface of the layers have been examined in planar view and cross-section by Transmission Electron Microscopy (TEM). The surface morphologies have been characterised by Scanning Electron Microscopy (SEM), and the bulk lattice perfection of the layers assessed using Double Crystal X-ray Diffraction (DCXRD).The surface morphology has been found to correlate with the growth conditions, with the type of defects grown-in to the layer (e.g. stacking faults, microtwins), and with the nature and density of dislocations in the interface.

COPPER ALLOY No. 268

Alloy Digest ◽  
1976 ◽  
Vol 25 (2) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Copper Alloy ◽  
Cold Working ◽  
Heat Treating ◽  
Zinc Alloy ◽  
Good Resistance ◽  
Wide Range ◽  
Copper Zinc ◽  
The Common ◽  
Cold Worked

Abstract Copper Alloy No. 268 is a copper-zinc alloy with excellent cold-working properties and good resistance to corrosion. It can be cold worked by all the common fabrication processes and has a wide range of applications. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-306. Producer or source: Brass mills.

Conclusion

2018 ◽  
Author(s):  
Matthew S. Seligmann
Keyword(s):  
Corporal Punishment ◽  
Social Reform ◽  
Alcohol Intake ◽  
Religious Practice ◽  
Royal Navy ◽  
The Poor ◽  
Wide Range ◽  
The Everyday ◽  
Push Forward ◽  
The Common

As this book has shown the common conception that ‘Churchill’s “radical phase” was cast to the winds’ when he was put in charge of the Navy in October 1911, although well established in the literature, is not, in fact, accurate.1 The radical President of the Board of Trade, eager to improve the lives of the poor, became the radical Home Secretary, no less enthusiastic for social reform, who then became the radical First Lord of the Admiralty, imbued with both a desire and, perhaps more importantly, a will to intervene in order to better conditions for those who served in the Royal Navy. Accordingly, he embarked upon a major programme of improvement across a wide range of different areas all of which affected the everyday life of sailors. Alcohol intake, sexual behaviour, religious practice, corporal punishment, as well as pay and equality of progression, all came under the spotlight while Churchill was First Lord. Of course, not all of the new measures were successful and not all were progressive in the modern understanding of the term, but all of them represented significant attempts to push forward a radical agenda for change....

Punk as Folk: Continuities and Tensions in the UK and Beyond

2020 ◽  
Author(s):  
Pete Dale
Keyword(s):  
Folk Music ◽  
Music Making ◽  
Collective Creativity ◽  
Living Tradition ◽  
Wide Range ◽  
The Us ◽  
The Common ◽  
The Individual ◽  
The Uk

Numerous claims have been made by a wide range of commentators that punk is somehow “a folk music” of some kind. Doubtless there are several continuities. Indeed, both tend to encourage amateur music-making, both often have affiliations with the Left, and both emerge at least partly from a collective/anti-competitive approach to music-making. However, there are also significant tensions between punk and folk as ideas/ideals and as applied in practice. Most obviously, punk makes claims to a “year zero” creativity (despite inevitably offering re-presentation of at least some existing elements in every instance), whereas folk music is supposed to carry forward a tradition (which, thankfully, is more recognized in recent decades as a subject-to-change “living tradition” than was the case in folk’s more purist periods). Politically, meanwhile, postwar folk has tended more toward a socialist and/or Marxist orientation, both in the US and UK, whereas punk has at least rhetorically claimed to be in favor of “anarchy” (in the UK, in particular). Collective creativity and competitive tendencies also differ between the two (perceived) genre areas. Although the folk scene’s “floor singer” tradition offers a dispersal of expressive opportunity comparable in some ways to the “anyone can do it” idea that gets associated with punk, the creative expectation of the individual within the group differs between the two. Punk has some similarities to folk, then, but there are tensions, too, and these are well worth examining if one is serious about testing out the common claim, in both folk and punk, that “anyone can do it.”

scholarly journals Zebrafish Models to Study New Pathways in Tauopathies

2021 ◽  
Vol 22 (9) ◽  
pp. 4626
Author(s):  
Clément Barbereau ◽  
Nicolas Cubedo ◽  
Tangui Maurice ◽  
Mireille Rossel
Keyword(s):  
Cognitive Deficits ◽  
Tau Protein ◽  
Common Point ◽  
Transgenic Models ◽  
Synaptic Loss ◽  
Wide Range ◽  
Transgenic Lines ◽  
Functional Consequences ◽  
The Common

Tauopathies represent a vast family of neurodegenerative diseases, the most well-known of which is Alzheimer’s disease. The symptoms observed in patients include cognitive deficits and locomotor problems and can lead ultimately to dementia. The common point found in all these pathologies is the accumulation in neural and/or glial cells of abnormal forms of Tau protein, leading to its aggregation and neurofibrillary tangles. Zebrafish transgenic models have been generated with different overexpression strategies of human Tau protein. These transgenic lines have made it possible to highlight Tau interacting factors or factors which may limit the neurotoxicity induced by mutations and hyperphosphorylation of the Tau protein in neurons. Several studies have tested neuroprotective pharmacological approaches. On few-days-old larvae, modulation of various signaling or degradation pathways reversed the deleterious effects of Tau mutations, mainly hTauP301L and hTauA152T. Live imaging and live tracking techniques as well as behavioral follow-up enable the analysis of the wide range of Tau-related phenotypes from synaptic loss to cognitive functional consequences.

scholarly journals Cyclotide host-defense tailored for species and environments in violets from the Canary Islands

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Blazej Slazak ◽  
Klara Kaltenböck ◽  
Karin Steffen ◽  
Martyna Rogala ◽  
Priscila Rodríguez-Rodríguez ◽  
...  
Keyword(s):  
Host Defense ◽  
Canary Islands ◽  
Cyclic Peptides ◽  
Fusarium Culmorum ◽  
Host Defense Peptides ◽  
Biological Assays ◽  
Minimal Inhibitory Concentrations ◽  
Wide Range ◽  
The Common ◽  
Teide Volcano

AbstractCyclotides are cyclic peptides produced by plants. Due to their insecticidal properties, they are thought to be involved in host defense. Violets produce complex mixtures of cyclotides, that are characteristic for each species and variable in different environments. Herein, we utilized mass spectrometry (LC–MS, MALDI-MS), transcriptomics and biological assays to investigate the diversity, differences in cyclotide expression based on species and different environment, and antimicrobial activity of cyclotides found in violets from the Canary Islands. A wide range of different habitats can be found on these islands, from subtropical forests to dry volcano peaks at high altitudes. The islands are inhabited by the endemic Viola palmensis, V. cheiranthifolia, V. anagae and the common V. odorata. The number of cyclotides produced by a given species varied in plants from different environments. The highest diversity was noted in V. anagae which resides in subtropical forest and the lowest in V. cheiranthifolia from the Teide volcano. Transcriptome sequencing and LC–MS were used to identify 23 cyclotide sequences from V. anagae. Cyclotide extracts exhibited antifungal activities with the lowest minimal inhibitory concentrations noted for V. anagae (15.62 μg/ml against Fusarium culmorum). The analysis of the relative abundance of 30 selected cyclotides revealed patterns characteristic to both species and populations, which can be the result of genetic variability or environmental conditions in different habitats. The current study exemplifies how plants tailor their host defense peptides for various habitats, and the usefulness of cyclotides as markers for chemosystematics.

Detection and characterization of Leptospira spp. in dogs diagnosed with kidney and/or liver disease in Selangor, Malaysia

2021 ◽  
pp. 104063872110245
Author(s):  
Sabri A. Rahman ◽  
Kuan H. Khor ◽  
Siti Khairani-Bejo ◽  
Seng F. Lau ◽  
Mazlina Mazlan ◽  
...  
Keyword(s):  
Liver Disease ◽  
Mortality Rate ◽  
Direct Detection ◽  
Bacterial Disease ◽  
Pathogenic Leptospira ◽  
Wide Range ◽  
Leptospira Spp ◽  
Rrna Sequencing ◽  
The Common

Leptospirosis is a serious bacterial disease that affects both humans and animals. A wide range of symptoms have been described in humans; the disease in dogs is commonly associated with kidney and/or liver disease. In Malaysia, information about the common serovars infecting dogs is limited. Therefore, we investigated the occurrences of leptospirosis in 124 pet dogs diagnosed with kidney and/or liver disease. Blood, urine, abdominal effusion, and/or kidney and liver were collected from the dogs. Based on microscopic agglutination testing, 53 of 124 (42.7%) dogs were seropositive for leptospiral exposure. Sera were frequently positive to serovars Bataviae ( n = 12), Javanica ( n = 10), and Icterohaemorrhagiae ( n = 10). Direct detection using PCR showed that 42 of 124 (33.9%) of the whole blood and 36 of 113 (31.9%) urine samples were positive for pathogenic Leptospira spp. By PCR, 2 of 23 (9.1%) kidney and 2 of 23 (9.1%) liver were positive for pathogenic Leptospira spp. Abdominal effusion from 4 dogs were PCR-positive for pathogenic Leptospira spp. The species detected were L. interrogans, L. borgpetersenii, L. kirschneri, and L. kmetyi by partial 16S rRNA sequencing. We further identified and characterized 11 Leptospira spp. isolates from 8 dogs as serovars Bataviae, Javanica, and Australis. The mortality rate of the Leptospira-infected dogs was high (18 of 53; 34%).

In Vivo and In Vitro Evaluation of Coated HAp Films with Different Surface Morphology

2007 ◽  
Vol 539-543 ◽  
pp. 710-715
Author(s):  
Kotaro Kuroda ◽  
Ryoichi Ichino ◽  
Masazumi Okido
Keyword(s):  
Bone Formation ◽  
Surface Morphology ◽  
New Bone Formation ◽  
Contact Ratio ◽  
Bone Implant ◽  
Ft Ir ◽  
Mouse Osteoblast ◽  
Surface Morphologies

Hydroxyapatite (HAp) coatings were formed on cp titanium plates and rods by the thermal substrate method in an aqueous solution that included 0.3 mM Ca(H2PO4)2 and 0.7 mM CaCl2. The coating experiments were conducted at 40-140 oC and pH = 8 for 15 or 30 min. The properties for the coated samples were studied using XRD, EDX, FT-IR, and SEM. All the specimens were covered with HAp, which had different surface morphologies such as net-like, plate-like and needle-like. After cleaning and sterilization, all the coated specimens were subjected to in vivo and vitro testing. In the in vitro testing, the mouse osteoblast-like cells (MC3T3-E1) were cultured on the coated and non-coated specimens for up to 30 days. Moreover, the specimens (φ2 x 5 mm) were implanted in rats femoral for up to 8 weeks, the osseoinductivity on them were evaluated. In in vitro evaluations, there were not significant differences between the different surface morphologies. In in vivo evaluations, however, two weeks postimplantation, new bone formed on both the HAp coated and non-coated titanium rods in the cancellous and cortical bone. The bone-implant contact ratio, which was used for the evaluation of new bone formation, was significantly dependent on the surface morphology of the HAp, and the results demonstrated that the needle-like coating appears to promote rapid bone formation.

The Anatomy of Justice: Forensic Medicine and Criminal Law In Nineteenth-century Egypt

1999 ◽  
Vol 6 (2) ◽  
pp. 224-271 ◽  
Author(s):  
Khaled Fahmy
Keyword(s):  
Nineteenth Century ◽  
Rule Of Law ◽  
Criminal Law ◽  
Forensic Medicine ◽  
Justice System ◽  
Reform Process ◽  
Archival Material ◽  
Wide Range ◽  
The Common ◽  
Arabic Speaking

AbstractThe reform of the Egyptian criminal justice system in the nineteenth century traditionally has been viewed as forming an important step in the establishment of a liberal and just rule of law. By studying how forensic medicine was introduced into nineteenth-century Egypt, I argue that the need to exercise better control over the population and to monitor crime lay behind the reform process as much as liberal ideas borrowed from Europe did. Drawing on a wide range of archival material, both legal and medical, I analyze the role played by autopsy in the criminal system and argue that the practice of autopsy was viewed differentially by 'ulamā', by Arabic-speaking, French-educated doctors and by the mostly illiterate masses. And contrary to the common wisdom, I conclude that the "modernization" of the Egyptian legal system was intended not to displace the sharīa but to support it.

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