Single-layer group IV-V and group V-IV-III-VI semiconductors: Structural stability, electronic structures, optical properties, and photocatalysis

2017 ◽  
Vol 96 (3) ◽  
Author(s):  
Jia-He Lin ◽  
Hong Zhang ◽  
Xin-Lu Cheng ◽  
Yoshiyuki Miyamoto
Keyword(s):  
Optical Properties ◽  
Structural Stability ◽  
Electronic Structures ◽  
Single Layer ◽  
Group Iv ◽  
Group V

Optical Properties and Band Structure of Group IV-VI and Group V Materials

1964 ◽  
Vol 133 (6A) ◽  
pp. A1685-A1697 ◽  
Author(s):  
Manuel Cardona ◽  
D. L. Greenaway
Keyword(s):  
Optical Properties ◽  
Band Structure ◽  
Group Iv ◽  
Group V

Electronic structures and optical properties of Ga doped single-layer indium nitride

2018 ◽  
Vol 31 (3) ◽  
pp. 313-317
Author(s):  
Zhi-wei Li ◽  
De-ping Guo ◽  
Guang-yi Huang ◽  
Wang-li Tao ◽  
Man-yi Duan
Keyword(s):  
Optical Properties ◽  
Electronic Structures ◽  
Indium Nitride ◽  
Single Layer

The electronic structures of group-V–group-IV hetero-bilayer structures: a first-principles study

2015 ◽  
Vol 17 (41) ◽  
pp. 27769-27776 ◽  
Author(s):  
Yanli Wang ◽  
Yi Ding
Keyword(s):  
First Principles ◽  
Electronic Structures ◽  
Van Der Waals ◽  
Interfacial Properties ◽  
Group Iv ◽  
Group V ◽  
First Principles Study

Van der Waals hetero-bilayer structures can be constructed from group-V and group-IV nanosheets, which exhibit tunable electronic and interfacial properties.

Single layer lead iodide: computational exploration of structural, electronic and optical properties, strain induced band modulation and the role of spin–orbital-coupling

Nanoscale ◽  
2015 ◽  
Vol 7 (37) ◽  
pp. 15168-15174 ◽  
Author(s):  
Mei Zhou ◽  
Wenhui Duan ◽  
Ying Chen ◽  
Aijun Du
Keyword(s):  
Optical Properties ◽  
Electronic Structures ◽  
Single Layer ◽  
Layered Materials ◽  
Two Dimensional ◽  
Lead Iodide ◽  
Spin Orbital ◽  
Computational Exploration ◽  
Spin Orbital Coupling

Graphitic like layered materials exhibit intriguing electronic structures and thus the search for new types of two-dimensional (2D) monolayer materials is of great interest for developing novel nano-devices.

Ab initio calculation on the Optical Properties of AA- Stacked two dimensional Graphene, Silicene, Germanene, and Stanene

2018 ◽  
Vol 1 (1) ◽  
pp. 46-50
Author(s):  
Rita John ◽  
Benita Merlin
Keyword(s):  
Optical Properties ◽  
Band Structure ◽  
Density Functional ◽  
Electronic Band Structure ◽  
Complex Refractive Index ◽  
Single Layer ◽  
Generalized Gradient ◽  
Electronic Band ◽  
Wide Range ◽  
Optical Region

In this study, we have analyzed the electronic band structure and optical properties of AA-stacked bilayer graphene and its 2D analogues and compared the results with single layers. The calculations have been done using Density Functional Theory with Generalized Gradient Approximation as exchange correlation potential as in CASTEP. The study on electronic band structure shows the splitting of valence and conduction bands. A band gap of 0.342eV in graphene and an infinitesimally small gap in other 2D materials are generated. Similar to a single layer, AA-stacked bilayer materials also exhibit excellent optical properties throughout the optical region from infrared to ultraviolet. Optical properties are studied along both parallel (||) and perpendicular ( ) polarization directions. The complex dielectric function (ε) and the complex refractive index (N) are calculated. The calculated values of ε and N enable us to analyze optical absorption, reflectivity, conductivity, and the electron loss function. Inferences from the study of optical properties are presented. In general the optical properties are found to be enhanced compared to its corresponding single layer. The further study brings out greater inferences towards their direct application in the optical industry through a wide range of the optical spectrum.

Different Treatment Protocols of Retained Fetal Membranes and its Effect on Serum Profile, Uterine Involution and Postpartum Fertility in Cows

2019 ◽  
Vol 14 (04) ◽  
Author(s):  
A. I. Shah ◽  
D. M. Patel ◽  
N. P. Sarvaiya ◽  
S. P. Madhira
Keyword(s):  
Group Iv ◽  
Fetal Membranes ◽  
Serum Progesterone ◽  
Group V ◽  
Manual Removal ◽  
Uterine Involution ◽  
Group I ◽  
Medicinal Treatment ◽  
Group Ii ◽  
Postpartum Estrus

This study was undertaken on 36 freshly calved cows randomly divided into 6 equal groups under field conditions. Cows of group-VI that shed placenta within 8-12 hours postpartum naturally served as healthy control. The cows with retained fetal membranes (RFM, n = 18) for more than 12 hrs were managed either by manual removal of placenta without antibiotics (group-I), parenteral antibiotic (Ceftiofur 1 g i/m) for three consecutive days (group-II) or a combination of both (group-III). In group-IV and group-V, cows were administered with Inj. Oxytocin @ 50 IU i/m and Inj. Dinoprost tromethamine (PGF2α) @ 25 mg i/m, respectively, immediately after parturition and time of placental shedding was recorded. The overall prevalence of Brucellosis by RBPT was found to be 5.55 % amongst these 36 animals. The placental expulsion in groups following medicinal treatment was found to be 50 (3/6) % in Ceftiofur alone by 3 days (group-II), and 66.67 (4/6) % in Oxytocin (group-IV) and 100 (6/6) % in PGF2α inj. (group-V) groups within 12 hrs. The time of uterine involution in groups I to VI was found to be 42.00 ± 1.94, 39.50 ± 0.99, 40.67 ± 1.39, 38.33 ± 1.55, 37.50 ± 1.02 and 37.33 ± 1.76 days, respectively, while the interval for the appearance of first postpartum estrus was 54.83 ± 2.06, 51.00 ± 1.05, 52.17 ± 1.96, 50.17 ± 2.03, 48.67 ± 1.90 and 49.17 ± 1.55 days, respectively, which did not vary statistically. The mean serum progesterone profile obtained on day 0 and day 21 postpartum was statistically non-significant between groups. However, it was significantly (p less than 0.05) lower on day 0 as compared to day 21 in group-I, II and VI. The levels on day 0 coincided with the time of blood sampling after calving. The high level of serum P4 on day 0 in group-IV and V could be due to sampling immediately after calving. The serum calcium and phosphorus levels were significantly(p less than 0.05) lower on day 0 than on day 21, but not the magnesium. The group effect was however non-significant for any of three minerals. It was observed that manual removal of RFM without parenteral antibiotics, resulted in puerperal metritis, cervicitis, pyometra which ultimately resulted into delayed uterine involution, delayed first postpartum estrus and thus, reduced the postpartum reproductive efficiency. It was inferred that the PGF2α and Oxytocin injections could be used as a treatment of choice for prevention of RFMs in cattle.

scholarly journals Effects of bisphosphonate and calcium carbonate on normal aortic valve and cholecalciferol induced in vivo rabbit aortic stenosis model

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Okutucu ◽  
C Sabanoglu ◽  
A Saglam Ayhan ◽  
E Tulumen ◽  
H Aksoy ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Aortic Valve ◽  
Aortic Stenosis ◽  
Calcium Supplementation ◽  
Group Iv ◽  
Histopathologic Examination ◽  
Group V ◽  
Group I ◽  
Alendronate Treatment

Abstract Background Calcific aortic valve disease (CAVD) is the most common valvular heart disease. Bisphosphonates are stable analogs of pyrophosphates and commonly prescribed in the treatment of osteoporosis. The effects of bisphosphonate treatment on CAVD are not clearly known and there are inconsistent results. Similarly, the effect of calcium supplementation on CAVD remains controversial. Purpose The aim of this study was to assess the effects of bisphosphonate therapy on the normal aortic valve and vitamin D induced in vivo rabbit aortic stenosis (AS) model. Methods The impact of calcium supplementation on the rabbit AS model was also evaluated. A total of 30 New Zealand white rabbits were divided into five equal groups: no treatment (Group I); 25,000 IU/day vitamin D3 (cholecalciferol) (Group II, rabbit AS model); 25,000 IU/day cholecalciferol plus 2500 mg/day calcium carbonate (Group III); 20 μg/kg/week intravenous alendronate (Group IV) and 25,000 IU/day cholecalciferol plus 2500 mg/day calcium carbonate plus 20μg/kg/week alendronate (Group V). Echocardiography was performed at baseline and after 12 weeks of treatment. The left ventricular mass index (LVMI), aortic valve area (AVA), transvalvular velocities and gradients were recorded. Radiologic and histopathologic examination was performed at the end of the 12th week. Control animals displayed no abnormalities of the aortic valve. Results There was no echocardiographic change in Group IV. In Groups II, III and V, there was a significant decrease in AVA and increases in transvalvular velocities and gradients. However, these stenotic changes were significantly prominent in Group V (p=0.001 for all, via repeated measures ANOVA). Moreover, LVMI was only increased in Group V (p<0.05). Calcification of aortic valvar complex was detected in 14 (46.7%) cases by radiologic imaging and 10 (33.3%) cases by histopathologic examination. Most frequent calcification was found in Group V (5 for each method, 83.3%). Agatston, volume and equivalent mass scores of calcific foci in Group V were significantly higher than other groups (p<0.05 for all). There was no significant difference between groups regarding with presence of osteoclasts in calcific foci. Conclusion Calcium supplementation has no effect on the in vivo rabbit AS model. Alendronate treatment aggravates the stenosis and increases the calcification in the rabbit AS model. Alendronate treatment has no effect on the normal valve in which there was no osteogenesis and osteoclastogenesis. Based on these findings, in patients with CAVD, alendronate treatment should be given with regular echocardiographic follow-up or may not be preferred. Central figure Funding Acknowledgement Type of funding source: None

scholarly journals Comparative Study on Electronic Structure and Optical Properties of α-Fe2O3, Ag/α-Fe2O3 and S/α-Fe2O3

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 424
Author(s):  
Cuihua Zhao ◽  
Baishi Li ◽  
Xi Zhou ◽  
Jianhua Chen ◽  
Hongqun Tang
Keyword(s):  
Optical Properties ◽  
Optical Absorption ◽  
Electronic Structures ◽  
Density Functional ◽  
Peak Strength ◽  
Visible Range ◽  
High Symmetry ◽  
Functional Theory ◽  
Optical Absorption Peak ◽  
Calculation Results

The electronic structures and optical properties of pure, Ag-doped and S-doped α-Fe2O3 were studied using density functional theory (DFT). The calculation results show that the structure of α-Fe2O3 crystal changes after Ag and S doping, which leads to the different points of the high symmetry of Ag-doped and S-doped α-Fe2O3 with that of pure α-Fe2O3 in the energy band, as well as different Brillouin paths. In addition, the band gap of α-Fe2O3 becomes smaller after Ag and S doping, and the optical absorption peak shifts slightly toward the short wavelength, with the increased peak strength of S/α-Fe2O3 and the decreased peak strength of Ag/α-Fe2O3. However, the optical absorption in the visible range is enhanced after Ag and S doping compared with that of pure α-Fe2O3 when the wavelength is greater than 380 nm, and the optical absorption of S-doped α-Fe2O3 is stronger than that of Ag-doped α-Fe2O3.

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