The Si(111) $\sqrt 3 \times \sqrt 3 $ SURFACES FORMED BY THE ADSORPTION OF GROUP-III, IV, AND V METALS

1994 ◽  
Vol 01 (02n03) ◽  
pp. 359-368 ◽  
Author(s):  
S. KONO
Keyword(s):  
Experimental Studies ◽  
Building Blocks ◽  
Group Iv ◽  
Scanning Tunneling ◽  
Hollow Site ◽  
Tunneling Microscopy ◽  
Group V ◽  
Group Iii ◽  
Metal Building ◽  
Geometric And Electronic Properties

A compilation of experimental studies is made on the properties of the Si(111) [Formula: see text] surfaces formed by the adsorption of metals of groups-III, IV, and V in the periodic table. The metals treated are Al, Ga, In (group-III), Sn, Pb (group-IV), Sb and Bi (group-V). Experimental studies using scanning tunneling microscopy are included only when they are necessary, since the topics will be covered in the review by J. Nogami in this issue. Theoretical aspects of the studies will be covered in the review by H. Nagayoshi in this issue. The geometric and electronic properties of these Si(111) [Formula: see text] surfaces appeared to be the simplest kinds of surfaces on the Si(111), thus providing prototypic examples of reconstruction on the metal/Si submonolayer interfaces. The simplicity in these surfaces is that there are metal-adatoms over essentially truncated Si(111) 1×1 substrates. The types of "metal building-blocks" are basically two: (i) a single metal adatom on a threefold hollow site (so-called T4 site), (ii) a metal trimer, each of constituent atoms, resides nearly on the ontop site (so-called "milk-stool"). There is large relaxation in the substrate Si due to the presence of metal adatoms.

scholarly journals Scanning Tunneling Microscopy Studies of InGaN Growth by Molecular Beam Epitaxy

1999 ◽  
Vol 4 (S1) ◽  
pp. 858-863
Author(s):  
Huajie Chen ◽  
A. R. Smith ◽  
R. M. Feenstra ◽  
D. W. Greve ◽  
J. E. Northrup
Keyword(s):  
Molecular Beam Epitaxy ◽  
Scanning Tunneling Microscopy ◽  
Molecular Beam ◽  
Surface Segregation ◽  
Growth Parameters ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Group V ◽  
Group Iii ◽  
Ingan Alloys

InGaN alloys with indium compositions ranging from 0–40% have been grown by molecular beam epitaxy. The dependence of the indium incorporation on growth temperature and group III/group V ratio has been studied. Scanning tunneling microscopy images, interpreted using first-principles theoretical computations, show that there is strong indium surface segregation on InGaN. Based on this surface segregation, a qualitative model is proposed to explain the observed indium incorporation dependence on the growth parameters.

ВЗАИМОСВЯЗЬ ПРОДУКТИВНЫХ ПОКАЗАТЕЛЕЙ КОРОВ ЧЕРНО-ПЕСТРОЙ ПОРОДЫ С ВОСПРОИЗВОДИТЕЛЬНЫМИ КАЧЕСТВАМИ

2019 ◽  
pp. 39-42
Author(s):  
G.Yu. BEREZKINA ◽  
S.L. VOROBYEVA ◽  
E.M. KISLYAKOVA ◽  
A.A. KOREPANOVA
Keyword(s):  
Experimental Studies ◽  
Live Weight ◽  
Group Iv ◽  
Reproductive Capacity ◽  
Group Vi ◽  
Group V ◽  
Group Iii ◽  
Group I ◽  
The Republic ◽  
Breeding Farms

Изучено влияние возраста и живой массы при первом осеменении на воспроизводительные качества коровпервотелок чернопестрой породы в племенных заводах Удмуртской Республики. Исследования проводились в период с 2015 по 2018 гг. Для проведения исследований были сформированы 6 групп животных в зависимости от возраста первого осеменения. В I группу вошли коровы с возрастом первого осеменения до 13 мес, во II от 13,1 до 15 мес, в III от 15,1 до 17, в IV от 17,1 до 19, в V от 19,1 до 21 и в VI группу от 21 мес и старше. При этом живая масса телок в I группе в среднем составила 349,5 кг, во II 370,9, в III 387,7, в IV 400,2, в V 420,7 и в VI группе 440,2 кг. Анализ возраста первого осеменения в племенных хозяйствах республики показал, что средний возраст плодотворного осеменения в 2018 году составил 17,0 мес. с живой массой 394 кг. По результатам экспериментальных исследований нами получено, что лучшие воспроизводительные показатели и молочная продуктивность выявлена у коровпервотелок, которых осеменяли в возрасте 14,6 мес. В данной группе продолжительность сервиспериода составила 127,3 дня, коэффициент воспроизводительной способности 0,90, выход телят на 100 коров составил более 85,3. Удой за 305 дней лактации, у коровпервотелок второй опытной группы составил 6332,3 кг с массовой долей жира 3,65 и белка 3,15 .The influence of age and live weight at the first insemination on reproductive qualities of cowsborn black and white breed in breeding farms of the Udmurt Republic was studied. The studies were conducted between 2015 and 2018. For the research 6 groups of animals were formed depending on the age of the first insemination. Group I included cows with the age of first insemination up to 13 months, in group II from 13.1 to 15 months, in III group from 15.1 to 17 months, in group IV from 17.1 to 19 months, in group V from 19.1 to 21 months and in VI group from 21 months and more. At the same time, the live weight of heifers in group I averaged 349.5 kg, in group II370.9 kg, in group III 387.7 kg, in group IV 400.2 kg, in group V 420.7 kg and in group VI 440.2 kg. The analysis of the age of the first insemination in breeding farms of the Republic showed that the average age of fruitful insemination in 2018 was 17.0 months with a live weight of 394 kg. According to the results of experimental studies, we obtained that the best reproductive performance and milk productivity was revealed in cows, which were inseminated at the age of 14.6 months. In this group, the duration of the service period was 127.3 days, the coefficient of reproductive capacity 0.90, yield of calves per 100 cows. Milk yield for 305 days of lactation, in cows of the second experimental group was 6332.3 kg with a mass fraction of fat 3.65 and protein 3.15.

Scanning Tunneling Microscopy Studies of InGaN Growth by Molecular Beam Epitaxy

1998 ◽  
Vol 537 ◽  
Author(s):  
Huajie Chen ◽  
A. R. Smith ◽  
R. M. Feenstra ◽  
D. W. Greve ◽  
J. E. Northrup
Keyword(s):  
Molecular Beam Epitaxy ◽  
Scanning Tunneling Microscopy ◽  
Molecular Beam ◽  
Surface Segregation ◽  
Growth Parameters ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Group V ◽  
Group Iii ◽  
Ingan Alloys

AbstractInGaN alloys with indium compositions ranging from 0–40% have been grown by molecular beam epitaxy. The dependence of the indium incorporation on growth temperature and group III/group V ratio has been studied. Scanning tunneling microscopy images, interpreted using first-principles theoretical computations, show that there is strong indium surface segregation on InGaN. Based on this surface segregation, a qualitative model is proposed to explain the observed indium incorporation dependence on the growth parameters.

In-Plane Asymmetries on the Ge(111)-c(2×8) Surface Mapped with the Scanning Tunneling Microscope

1992 ◽  
Vol 295 ◽  
Author(s):  
P. Molinàs-Mata ◽  
J. Zegenhagen ◽  
M. Böhringer ◽  
N. Takeuchi ◽  
A. Selloni
Keyword(s):  
Local Density ◽  
Experimental Studies ◽  
Surface States ◽  
Small Sample ◽  
Constant Current ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Low Energy Electron ◽  
Tunneling Currents ◽  
Insight Into

AbstractWe report on new experimental studies of the Ge(111)-c(2×8) reconstruction performed with low-energy electron diffraction. (LEED) and scanning tunneling microscopy (STM). Weak quarter-order reflections are present in the c(2 × 8) LEED pattern in agreement with previous observations and results of ab initio calculations. In order to gain insight into the predicted splitting of dangling bond states, we compare constant current topographs (CCT's) performed at high-tunneling currents (40.nA) with first-principles calculations of the local density of states (LDOS) 1Å above the surface adatoms and obtain good qualitative agreement. We finally discuss to what extent the STM CCT's at high tunneling currents (small sample-tip distances (STD)) are sensitive to surface states outside the Г point.

A Study on the Effect of Samoa Extract (Cleome droserifolia) on Sperm Quality in Male Albino Rats Exposed to Pyrethroid

2021 ◽  
pp. 39-45
Author(s):  
Nura I. Al-Zail ◽  
Salah F. Kamies
Keyword(s):  
Sperm Quality ◽  
Group Iv ◽  
Male Rats ◽  
Control Group ◽  
Albino Rats ◽  
Protective Agent ◽  
Group V ◽  
Group Iii ◽  
Group I ◽  
Induced Changes

Pyrethroid cyhalothrin (PC) is an insecticide that is used worldwide for pest control in agriculture and household use. Samoa extract (SE) is a potent antioxidant protecting cells from oxidative stress. The present study investigates the protective and therapeutic effect of SE on PC-induced changes in sperm quality in male rats. Fifty adult male albino rats were divided into five groups: group I: served as control; group II: received PC i.p. only (6.2 mg/kg b.wt.); group III: received SE only (100 mg/kg b.wt., p.o.) for eight weeks; group IV: received SE as a protective agent daily for eight weeks, then followed by the administration of PC (i.p.) three times a week for two weeks; group V: exposed to PC (i.p.) three times a week for two weeks, then treated with the SE daily for 8 weeks. Results showed that PC caused markedly impaired sperm quality (a count, viability, motility, and abnormality). Compared to PC-treated animals, SE in the protective group markedly restored the alteration of sperm indices. However, SE in the curative group was found to be less effective in restoring PC-induced alterations. In conclusion, the data of this study revealed that the SE as a protective agent is more effective than as a therapeutic agent. Keywords: Samoa; Pyrethroid; Sperm quality; Rat

Effect of amino acid infusion on renal hemodynamics in humans: a dose-response study

1994 ◽  
Vol 267 (5) ◽  
pp. F703-F708 ◽  
Author(s):  
M. Giordano ◽  
P. Castellino ◽  
E. L. McConnell ◽  
R. A. DeFronzo
Keyword(s):  
Amino Acid ◽  
Dose Response ◽  
Renal Hemodynamics ◽  
Group Iv ◽  
Group V ◽  
Group Iii ◽  
Amino Acid Infusion ◽  
Group I ◽  
Basal Plasma ◽  
Group Ii

We evaluated the dose-response relationship between the plasma amino acid (AA) concentration and renal hemodynamics in eight normal subjects. After an overnight fast, a balanced 10% AA solution was infused for 180 min at five separate infusion rates: 0.5 (group I), 1.0 (group II), 2.0 (group III), 4.0 (group IV), and 6.0 (group V) ml.kg-1.min-1 on separate days. Basal plasma AA concentration was 1.87 +/- 0.1 mmol/l and increased to 2.26 +/- 0.1 (group I), 2.66 +/- 0.2 (group II), 3.79 +/- 0.5 (group III), 5.81 +/- 0.4 (group IV), and 7.41 +/- 0.4 mmol/l (group V). Basal glomerular filtration rate (GFR) and renal plasma flow (RPF) averaged 95 +/- 4 and 476 +/- 29 ml.1.73 m-2.min-1, respectively, and rose to 98 +/- 5 and 506 +/- 40 (group I) [P = not significant (NS)], 102 +/- 3 and 533 +/- 30 (group II) (P < 0.05 vs. basal), 110 +/- 4 and 567 +/- 29 (group III), 115 +/- 7 and 610 +/- 55 (group IV), and 117 +/- 7 and 614 +/- 66 ml.1.73 m-2.min-1 (group V) (P = NS vs. group IV). Basal plasma glucagon concentration averaged 68 +/- 10 pg/ml and increased to 74 +/- 10 (group I), 83 +/- 11 (group II) (P < 0.05 vs. basal), 100 +/- 14 (group III), 121 +/- 14 (group IV), and 229 +/- 35 pg/ml (group V) (P < 0.01 vs. basal). Increases in plasma growth hormone (GH) and insulin levels were observed only during groups IV and V.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals The Effect of Flowable Composite Lining Thickness with Various Curing Techniques on Microleakage in Class II Composite Restorations: An in vitro Study

2013 ◽  
Vol 14 (1) ◽  
pp. 56-60 ◽  
Author(s):  
S Nagalaxmi Reddy ◽  
DN Jayashankar ◽  
Mohanthomas Nainan
Keyword(s):  
In Vitro Study ◽  
Class Ii ◽  
Group Iv ◽  
Group V ◽  
Group Iii ◽  
Flowable Composite ◽  
Composite Restorations ◽  
Group I ◽  
Composite Lining

ABSTRACT Aim Aim of this study was to compare class II composite restoration using flowable composites as lining with various thickness and curing techniques by evaluating cervical marginal microleakage. Materials and methods Fifty intact molars, each prepared with two box-only class II cavities, were randomly divided into five groups: Group I, P60 filling alone; group II, ultrathin flowable composite lining (0.5-1mm) cocured with overlying composite; group III, thin lining (1-1.5) cocured with overlying composite; group IV, ultrathin lining (0.5-1 mm) precured and group V, thin lining (1-1.5) precured. The teeth were then thermocycled for 1500 cycles (between 5 and 60 °C) and immersed in dye for 24 hours. Cervical microleakage was measured as the extent of dye penetration. Results Cocured specimens (groups II and III) showed least microleakage and control specimens (group I) showed maximum microleakage. On comparison of curing techniques, cocured specimens (groups II and III) showed less microleakage than precured (groups IV and V). On comparison of lining thickness and type of curing, group IV showed less microleakage than group V. Groups II and III were statistically not significant. Conclusion It was concluded from the results that ultrathin cocured flowable composite lining specimens improved the marginal sealing with decreased microleakage. Clinical significance In this study, the application of additional flowable composite lining with various thicknesses presented different influences in marginal quality of class II box only composite restorations. A new technique applying an ultrathin flowable composite lining with cocuring technique improved the marginal sealing with decreased microleakage. Restorations with thin lining presented reduced marginal integrity after thermocycling. How to cite this article Reddy SN, Jayashankar DN, Nainan M, Shivanna V. The Effect of Flowable Composite Lining Thickness with Various Curing Techniques on Microleakage in Class II Composite Restorations: An in vitro Study. J Contemp Dent Pract 2013;14(1):56-60.

Group-IV and group-V substitutional impurities in cubic group-III nitrides

2003 ◽  
Vol 68 (8) ◽  
Author(s):  
L. E. Ramos ◽  
J. Furthmüller ◽  
J. R. Leite ◽  
L. M. R. Scolfaro ◽  
F. Bechstedt
Keyword(s):  
Group Iii Nitrides ◽  
Group Iv ◽  
Group V ◽  
Group Iii ◽  
Substitutional Impurities

scholarly journals Effect of a Diet Composed of Genetically Modified Feed Components on the Selected Immune Parameters in Pigs, Cattle, and Poultry

2013 ◽  
Vol 57 (2) ◽  
pp. 209-217 ◽  
Author(s):  
Dariusz Bednarek ◽  
Katarzyna Dudek ◽  
Krzysztof Kwiatek ◽  
Małgorzata Świątkiewicz ◽  
Sylwester Świątkiewicz ◽  
...  
Keyword(s):  
Soybean Meal ◽  
Genetically Modified ◽  
Group Iv ◽  
Group Vi ◽  
Group V ◽  
Group Iii ◽  
Immune Parameters ◽  
Group I ◽  
Toxin Protein ◽  
Gm Soybean

Abstract The aim of the study was to evaluate the immune effects of genetically modified (GM), insect resistant corn (MON810) expressing toxin protein of Bacillus thuringiensis, and glyphosate-tolerant soybean meal (Roundup Ready MON-40-30-2), which are used as the feed mixture components in domestic animals. The study was conducted on 60 pigs (36 fatteners and 24 sows), 20 calves, 40 broilers, and 40 laying hens. Each species was divided into four basic nutritional groups: group I (control) - conventional feed, group II - feed consisted of GM soybean meal and non-modified corn, group III - non-modified soybean meal and GM corn, group IV - GM soybean meal and GM corn. Moreover, in the experiment on fatteners two additional groups were formed: group V - animals fed both conventional soybean meal and bruised grain, and group VI - GM soybean meal and conventional bruised grain. The results of study did not reveal any significant effect of feed mixtures containing GM components on the immune response in all animals regardless of their species and technological producing groups.

scholarly journals Essential Oils of some Mentha Species and Cultivars, their Chemistry and Bacteriostatic Activity

2016 ◽  
Vol 11 (7) ◽  
pp. 1934578X1601100 ◽  
Author(s):  
Agnieszka Ludwiczuk ◽  
Anna Kiełtyka-Dadasiewicz ◽  
Rafał Sawicki ◽  
Joanna Golus ◽  
Grażyna Ginalska
Keyword(s):  
Essential Oils ◽  
Staphylococcus Epidermidis ◽  
Reference Strain ◽  
Group Iv ◽  
Major Constituent ◽  
Bacteriostatic Activity ◽  
Major Purpose ◽  
Group V ◽  
Group Iii ◽  
Group I

The major purpose of this study was to determine the chemical relationships between the essential oils (EO) obtained form 18 mint samples of different species and its cultivars. GC/MS analysis of all essential oils showed that oxygenated monoterpenoids are the major components of these oils, with the exception of Mentha arvensis ‘Banana’. Based on the chemical composition of the essential oils, the analyzed mints can be divided into five groups. Group I was characterized by the presence of menthol and menthone, piperitenone oxide is the major constituent of group II, linalool of group III, carvone characterizes group IV, while 3-octanone is the most characteristic compound for group V. A reference strain of biofilm forming Staphylococcus epidermidis ATTC 35984 was tested against the obtained essential oils. Two of them, M. suaveolens ‘Variegata’ and M. x piperita ‘Almira’ exhibited significant bacteriostatic activity. The MIC values of these EOs were 0.25% and 0.5% respectively in comparison with an average MIC of 4% of the other tested mint EOs. Both active EOs are characterized by the presence of piperitenone oxide as the major component.

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