scholarly journals Tuning of Precursor Composition and Formation Pathway of Kesterite Absorbers using an in‐process Composition Shift: A Path towards Higher Efficiencies?

Solar RRL ◽  
2021 ◽  
Author(s):  
David Nowak ◽  
Teoman Taskesen ◽  
Devendra Pareek ◽  
Timo Pfeiffelmann ◽  
Ulf Mikolajczak ◽  
...  
Keyword(s):  
Formation Pathway ◽  
Process Composition ◽  
Precursor Composition

Structure and Activity of Pentacyclic Triterpenes Codrugs. A Review

2021 ◽  
Vol 21 ◽  
Author(s):  
Justyna Żwawiak ◽  
Anna Pawełczyk ◽  
Dorota Olender ◽  
Lucjusz Zaprutko
Keyword(s):  
Biological Activities ◽  
Anticancer Activities ◽  
Drug Molecule ◽  
Pentacyclic Triterpene ◽  
Formation Pathway ◽  
Chemical Systems ◽  
Drug Molecules ◽  
Wide Range ◽  
Anti Hiv ◽  
Structure And Activity

: Triterpenes are a wide and important group of compounds that have several promising pharmacological properties, such as hepatoprotective, anti-inflammatory, anti-HIV, antioxidant, or anticancer activities. Such potent substances can be successfully incorporated in more complex chemical systems e.g. codrugs or pro-drugs that have better pharmacological profile. The codrug is connected with a drug formation pathway to chemically cohere at least two drug molecules to improve positive therapeutic efficiency or decrease side effects. The codrug can be cleaved in the organism to generate effective compounds previously used as substrates. This article presents an overview of codrugs that consist of pentacyclic triterpene moiety that is chosen as a basic codrug moiety due to their wide range of vital activities and another drug molecule fragment. It was found that triterpenoid codrugs are characterized by a wide range of biological activities. However, most of them have anticancer potency.

Enhanced Spatial Photoluminescence Homogeneity and Fluorescence Density in MAPbI3 Films via Tailoring the Pb-Precursor Composition and Surface Morphology

2021 ◽  
Vol 3 (3) ◽  
pp. 1058-1070
Author(s):  
Bhanu Pratap Dhamaniya ◽  
Kartiki Chandratre ◽  
Priyanka Chhillar ◽  
Amit Kumar ◽  
Krishna Priya Ganesan ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Precursor Composition

HOP: A process model for synchronous hardware; semantics and experiments in process composition

Integration ◽  
1989 ◽  
Vol 8 (3) ◽  
pp. 209-247 ◽  
Author(s):  
Ganesh C. Gopalakrishnan ◽  
Richard M. Fujimoto ◽  
Venkatesh Akella ◽  
Narayana S. Mani
Keyword(s):  
Process Model ◽  
Process Composition

An Anomalous Formation Pathway for Dislocation-Sulfur Vacancy Complexes in Polycrystalline Monolayer MoS2

Nano Letters ◽  
2015 ◽  
Vol 15 (10) ◽  
pp. 6855-6861 ◽  
Author(s):  
Zhi Gen Yu ◽  
Yong-Wei Zhang ◽  
Boris I. Yakobson
Keyword(s):  
Monolayer Mos2 ◽  
Sulfur Vacancy ◽  
Formation Pathway ◽  
Anomalous Formation

Synergistic reaction between SO2 and NO2 on mineraloxides: a potential formation pathway of sulfate aerosol

2012 ◽  
Vol 14 (5) ◽  
pp. 1668-1676 ◽  
Author(s):  
Chang Liu ◽  
Qingxin Ma ◽  
Yongchun Liu ◽  
Jinzhu Ma ◽  
Hong He
Keyword(s):  
Sulfate Aerosol ◽  
Formation Pathway ◽  
Potential Formation ◽  
Synergistic Reaction

scholarly journals Iron and Carbon Isotope Constraints on the Formation Pathway of Iron-Rich Carbonates within the Dagushan Iron Formation, North China Craton

Minerals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 94
Author(s):  
Xiaoxue Tong ◽  
Kaarel Mänd ◽  
Yuhao Li ◽  
Lianchang Zhang ◽  
Zidong Peng ◽  
...  
Keyword(s):  
Iron Reduction ◽  
Isotope Composition ◽  
Iron Formation ◽  
Banded Iron Formations ◽  
Organic C ◽  
Formation Pathway ◽  
Wide Range ◽  
Dissimilatory Iron Reduction ◽  
O Isotope ◽  
Iron Formations

Banded iron formations (BIFs) are enigmatic chemical sedimentary rocks that chronicle the geochemical and microbial cycling of iron and carbon in the Precambrian. However, the formation pathways of Fe carbonate, namely siderite, remain disputed. Here, we provide photomicrographs, Fe, C and O isotope of siderite, and organic C isotope of the whole rock from the ~2.52 Ga Dagushan BIF in the Anshan area, China, to discuss the origin of siderite. There are small magnetite grains that occur as inclusions within siderite, suggesting a diagenetic origin of the siderite. Moreover, the siderites have a wide range of iron isotope compositions (δ56FeSd) from −0.180‰ to +0.463‰, and a relatively negative C isotope composition (δ13CSd = −6.20‰ to −1.57‰). These results are compatible with the reduction of an Fe(III)-oxyhydroxide precursor to dissolved Fe(II) through microbial dissimilatory iron reduction (DIR) during early diagenesis. Partial reduction of the precursor and possible mixing with seawater Fe(II) could explain the presence of siderite with negative δ56Fe, while sustained reaction of residual Fe(III)-oxyhydroxide could have produced siderite with positive δ56Fe values. Bicarbonate derived from both DIR and seawater may have provided a C source for siderite formation. Our results suggest that microbial respiration played an important role in the formation of siderite in the late Archean Dagushan BIF.

Experimental Study of the Effect of Precursor Composition On the Microstructure of Gallium Nitride Thin Films Grown by the MOCVD Process

2021 ◽  
Author(s):  
Omar D. Jumaah ◽  
Yogesh Jaluria
Keyword(s):  
Thin Films ◽  
Gallium Nitride ◽  
Chemical Vapor Deposition ◽  
Deposition Rate ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Transport Processes ◽  
Carrier Gas ◽  
Precursor Composition

Abstract Chemical vapor deposition (CVD) is a widely used manufacturing process for obtaining thin films of materials like silicon, silicon carbide, graphene and gallium nitride that are employed in the fabrication of electronic and optical devices. Gallium nitride (GaN) thin films are attractive materials for manufacturing optoelectronic device applications due to their wide band gap and superb optoelectronic performance. The reliability and durability of the devices depend on the quality of the thin films. The metal-organic chemical vapor deposition (MOCVD) process is a common technique used to fabricate high-quality GaN thin films. The deposition rate and uniformity of thin films are determined by the thermal transport processes and chemical reactions occurring in the reactor, and are manipulated by controlling the operating conditions and the reactor geometrical configuration. In this study, the epitaxial growth of GaN thin films on sapphire (AL2O3) substrates is carried out in two commercial MOCVD systems. This paper focuses on the composition of the precursor and the carrier gases, since earlier studies have shown the importance of precursor composition. The results show that the flow rate of trimethylgallium (TMG), which is the main ingredient in the process, has a significant effect on the deposition rate and uniformity of the films. Also the carrier gas plays an important role in deposition rate and uniformity. Thus, the use of an appropriate mixture of hydrogen and nitrogen as the carrier gas can improve the deposition rate and quality of GaN thin films.

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