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Lanthanide metal-organic frameworks (Ln-MOFs) exhibit outstanding properties, including high chemical and thermal stability, as well as their promising enzyme-mimic activity (MOFzyme). A new cerium MOFs (Ce-MOF) was synthesized via a solvothermal method using organic linker 4,4′,4″-nitrilotribenzoic acid (H3NTB). The crystallinity of the prepared material was confirmed using X-ray diffraction (XRD). The coordination between Ce and H3NTB was approved using Fourier transforms infrared (FT-IR). The chemical and oxidation state of Ce-MOF was characterized using X-ray photoelectron spectroscopy (XPS). The analysis of XPS data suggested the presence of two oxidation states of cerium, i.e., Ce(III) and Ce(IV). According to the imaging using a scanning electron microscope (SEM) and transmission electron microscope (TEM), Ce-MOF exhibits hexagonal rods’ morphology. Ce-MOF offered thermal stability up to 350 °C. It showed a fluorescence emission signal at wavelength 550 nm with a Stock’s shift of 200 nm. Ce-MOF’s application as a probe for sensing hydrogen peroxide (H2O2) and ferric ions (Fe3+) was reported. Ce-MOF exhibited peroxidase MOFzyme activity. Thus, it offered a turn-on emission upon interaction with different concentrations of H2O2. It detects Fe3+ ions with a limit of detection (LOD) and a linear range of 0.016 µM and 0.016–0.133 µM, respectively. The study also investigated the mechanisms of sensing for H2O2 and Fe3+ ions. The changes in the emission signals were due to the intrinsic catalase activity of Ce-MOF. Ce-MOF offered MOFzyme properties providing a promising feature for biocatalysis and biosensing applications.

Abstract: Background: The addition of nanofillers to polymers for enhanced performance is deliv-ering more interesting applications for aerospace, aeronautic industries, and other numerous nano-technical applications.
Objective: The aim was, therefore, to examine the role of graphene nanopowder on the thermal
stability and conductivity of the poly(vinyl alcohol)/poly(vinyl pyrrolidone) (PVA/PVP) polymer
nanocomposites.
Methods: In this work, graphene nanofillers were incorporated into the PVA/PVP polymer blended
by solution mixing for the preparation of nanocomposite films.
Results: Results showed that increasing graphene ratio improved thermal conductivity up to 330%,
moreover enhancing hardness shore A up to 16.3% compared to pure PVA/PVP blend polymer.
TGA analysis confirmed that the PVA/PVP and graphene network showed good thermal stability.
Conclusion: From the present findings, it is proved that PVA/PVP blends have profound effects on
thermal stability that cannot be attained by using individual counterparts. The property of the nano-composite depends on the host blend, morphology, and interfacial characteristics.

Abstract: Background: The addition of nanofillers to polymers for enhanced performance is deliv-ering more interesting applications for aerospace, aeronautic industries, and other numerous nano-technical applications.
Objective: The aim was, therefore, to examine the role of graphene nanopowder on the thermal
stability and conductivity of the poly(vinyl alcohol)/poly(vinyl pyrrolidone) (PVA/PVP) polymer
nanocomposites.
Methods: In this work, graphene nanofillers were incorporated into the PVA/PVP polymer blended
by solution mixing for the preparation of nanocomposite films.
Results: Results showed that increasing graphene ratio improved thermal conductivity up to 330%,
moreover enhancing hardness shore A up to 16.3% compared to pure PVA/PVP blend polymer.
TGA analysis confirmed that the PVA/PVP and graphene network showed good thermal stability.
Conclusion: From the present findings, it is proved that PVA/PVP blends have profound effects on
thermal stability that cannot be attained by using individual counterparts. The property of the nano-composite depends on the host blend, morphology, and interfacial characteristics.

Integrated lithostratigraphic and biostratigraphic data of two well-exposed Maastrichtian–Pa le oc en e s uc ce ss io ns , n am el y, t he Owina and the Abu Minqar sections (Dakhla Oasis, Western Desert, Egypt), led to enhance the age resolution and shed lights on the paleoenvironmental conditions throughout the deposition of the investigated sequences. The integrated biostratigraphic data
provide eight calcareous planktonic zones (five planktonic foraminifera, and three calcareous nannofossil zones) cover the studied interval. The paleoenvironmental setting of the Maastrichtian interval which represented by the lower Kharga Shale
unit ( Micula murus and Gansserina gansseri calcareous plankton zones) reveals shallow marine environmental conditions of innerneriticprobablyofmarginalsetting with highorganic matterinfluxand low-oxygenlevelinterruptedbysometransgressive
phases. While, shallower marine conditions associated with a sea-level drop mark the Cretaceous/Paleogene (K/Pg) boundary. The lowermost part of the Paleocene interval (NP3, NP4, P1b, P1c, and P2 calcareous plankton zones) which covered the lower partof the upper KhargaShale unitis markedby middle-outerneritic depositional setting,well-oxygenated seawater, aswell as a low organic matter influx coupled with relative sea-level rise. Above this level until reach the base of the Tarawan Formation, a major drop in the sea-level is observed. This interval is marked by absence of the calcareous planktonic taxa. Only agglutinated foraminiferal taxaare recordedduringthisinterval. While the TarawanFormation (P4bplanktonicforaminiferal Zone) is marked by outer neritic depositional setting that represents a sea-level transgressive phase. According to the field observations and the presence/absence of the calcareous planktonic zonal marker species; two tectonic events are detected. The tectonic event I took place at the K/Pg boundary and resulted in a significant hiatus at the studied area. Tectonic event II is observed at the contact between the Dakhla and the Tarawan formations across the Danian–Selandian transition. It is evidenced by the existence of an erosive (irregular) surface at the basal part of the Tarawan Formation. These events could be attributed to the echo of the Syrian Arc tectonism which interrupted the global sea-level curve throughout the Maastrichtian–Paleocene time.

Integrated lithostratigraphic and biostratigraphic data of two well-exposed Maastrichtian–Pa le oc en e s uc ce ss io ns , n am el y, t he Owina and the Abu Minqar sections (Dakhla Oasis, Western Desert, Egypt), led to enhance the age resolution and shed lights on the paleoenvironmental conditions throughout the deposition of the investigated sequences. The integrated biostratigraphic data
provide eight calcareous planktonic zones (five planktonic foraminifera, and three calcareous nannofossil zones) cover the studied interval. The paleoenvironmental setting of the Maastrichtian interval which represented by the lower Kharga Shale
unit ( Micula murus and Gansserina gansseri calcareous plankton zones) reveals shallow marine environmental conditions of innerneriticprobablyofmarginalsetting with highorganic matterinfluxand low-oxygenlevelinterruptedbysometransgressive
phases. While, shallower marine conditions associated with a sea-level drop mark the Cretaceous/Paleogene (K/Pg) boundary. The lowermost part of the Paleocene interval (NP3, NP4, P1b, P1c, and P2 calcareous plankton zones) which covered the lower partof the upper KhargaShale unitis markedby middle-outerneritic depositional setting,well-oxygenated seawater, aswell as a low organic matter influx coupled with relative sea-level rise. Above this level until reach the base of the Tarawan Formation, a major drop in the sea-level is observed. This interval is marked by absence of the calcareous planktonic taxa. Only agglutinated foraminiferal taxaare recordedduringthisinterval. While the TarawanFormation (P4bplanktonicforaminiferal Zone) is marked by outer neritic depositional setting that represents a sea-level transgressive phase. According to the field observations and the presence/absence of the calcareous planktonic zonal marker species; two tectonic events are detected. The tectonic event I took place at the K/Pg boundary and resulted in a significant hiatus at the studied area. Tectonic event II is observed at the contact between the Dakhla and the Tarawan formations across the Danian–Selandian transition. It is evidenced by the existence of an erosive (irregular) surface at the basal part of the Tarawan Formation. These events could be attributed to the echo of the Syrian Arc tectonism which interrupted the global sea-level curve throughout the Maastrichtian–Paleocene time.

Integrated lithostratigraphic and biostratigraphic data of two well-exposed Maastrichtian–Pa le oc en e s uc ce ss io ns , n am el y, t he Owina and the Abu Minqar sections (Dakhla Oasis, Western Desert, Egypt), led to enhance the age resolution and shed lights on the paleoenvironmental conditions throughout the deposition of the investigated sequences. The integrated biostratigraphic data
provide eight calcareous planktonic zones (five planktonic foraminifera, and three calcareous nannofossil zones) cover the studied interval. The paleoenvironmental setting of the Maastrichtian interval which represented by the lower Kharga Shale
unit ( Micula murus and Gansserina gansseri calcareous plankton zones) reveals shallow marine environmental conditions of innerneriticprobablyofmarginalsetting with highorganic matterinfluxand low-oxygenlevelinterruptedbysometransgressive
phases. While, shallower marine conditions associated with a sea-level drop mark the Cretaceous/Paleogene (K/Pg) boundary. The lowermost part of the Paleocene interval (NP3, NP4, P1b, P1c, and P2 calcareous plankton zones) which covered the lower partof the upper KhargaShale unitis markedby middle-outerneritic depositional setting,well-oxygenated seawater, aswell as a low organic matter influx coupled with relative sea-level rise. Above this level until reach the base of the Tarawan Formation, a major drop in the sea-level is observed. This interval is marked by absence of the calcareous planktonic taxa. Only agglutinated foraminiferal taxaare recordedduringthisinterval. While the TarawanFormation (P4bplanktonicforaminiferal Zone) is marked by outer neritic depositional setting that represents a sea-level transgressive phase. According to the field observations and the presence/absence of the calcareous planktonic zonal marker species; two tectonic events are detected. The tectonic event I took place at the K/Pg boundary and resulted in a significant hiatus at the studied area. Tectonic event II is observed at the contact between the Dakhla and the Tarawan formations across the Danian–Selandian transition. It is evidenced by the existence of an erosive (irregular) surface at the basal part of the Tarawan Formation. These events could be attributed to the echo of the Syrian Arc tectonism which interrupted the global sea-level curve throughout the Maastrichtian–Paleocene time.

Integrated lithostratigraphic and biostratigraphic data of two well-exposed Maastrichtian–Pa le oc en e s uc ce ss io ns , n am el y, t he Owina and the Abu Minqar sections (Dakhla Oasis, Western Desert, Egypt), led to enhance the age resolution and shed lights on the paleoenvironmental conditions throughout the deposition of the investigated sequences. The integrated biostratigraphic data
provide eight calcareous planktonic zones (five planktonic foraminifera, and three calcareous nannofossil zones) cover the studied interval. The paleoenvironmental setting of the Maastrichtian interval which represented by the lower Kharga Shale
unit ( Micula murus and Gansserina gansseri calcareous plankton zones) reveals shallow marine environmental conditions of innerneriticprobablyofmarginalsetting with highorganic matterinfluxand low-oxygenlevelinterruptedbysometransgressive
phases. While, shallower marine conditions associated with a sea-level drop mark the Cretaceous/Paleogene (K/Pg) boundary. The lowermost part of the Paleocene interval (NP3, NP4, P1b, P1c, and P2 calcareous plankton zones) which covered the lower partof the upper KhargaShale unitis markedby middle-outerneritic depositional setting,well-oxygenated seawater, aswell as a low organic matter influx coupled with relative sea-level rise. Above this level until reach the base of the Tarawan Formation, a major drop in the sea-level is observed. This interval is marked by absence of the calcareous planktonic taxa. Only agglutinated foraminiferal taxaare recordedduringthisinterval. While the TarawanFormation (P4bplanktonicforaminiferal Zone) is marked by outer neritic depositional setting that represents a sea-level transgressive phase. According to the field observations and the presence/absence of the calcareous planktonic zonal marker species; two tectonic events are detected. The tectonic event I took place at the K/Pg boundary and resulted in a significant hiatus at the studied area. Tectonic event II is observed at the contact between the Dakhla and the Tarawan formations across the Danian–Selandian transition. It is evidenced by the existence of an erosive (irregular) surface at the basal part of the Tarawan Formation. These events could be attributed to the echo of the Syrian Arc tectonism which interrupted the global sea-level curve throughout the Maastrichtian–Paleocene time.

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