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•Eu(III) was coordinated with organic antenna ligands and doped into bio-MOF-1 via cation exchange for O2 optical sensing.•A large conjugation plane improved sensitivity and decreased ...response time since it increased dynamic collision probability.•A highest sensitivity and a shortest response time were obtained as 6.96 and 12 s.•Sensing mechanism was revealed as O2 dynamic quenching on long-range energy roll-back procedure.
In this paper, a lanthanide cation, Eu(III), was firstly coordinated with a series of organic antenna ligands and then doped into bio-MOF-1 via cation exchange for O2 optical sensing. These organic ligands were supposed to increase dynamic collision probability between O2 molecules and excited probe molecules, so that sensitivity could be increased and response time could be decreased. These composite samples were firstly identified using SEM, XRD, N2 adsorption/desorption and ICP measurement to confirm their microstructure. Then their absorption spectra, emission spectra and emission lifetimes were discussed. It was found that these composite samples showed long emission lifetime up to 595 μs, which ensured enough time for O2 collision. Their O2 sensing performance was discussed via their emission spectra under increasing O2 concentrations. Linear sensing curves were observed for all samples. It was found that a large conjugation plane improved sensitivity and decreased response time since this large conjugation plane increased dynamic collision probability. The sensing mechanism was confirmed as the O2 quenching on long-range energy roll-back from ligand triplet state to bio-MOF-1. The highest sensitivity and the shortest response time were obtained as 6.96, three times higher than literature values, and 12 s, respectively.
The Late Paleozoic magmatism in central Inner Mongolia provides important insights on the tectonic evolution and crustal growth in the Central Asian Orogenic Belt (CAOB), which formed due to the ...closure of the Paleo-Asian Ocean (PAO). This paper presents new zircon UPb ages and Hf isotopic compositions as well as whole-rock geochemical data on a suite of volcanic rocks from the Late Paleozoic Baoligaomiao Formation and coeval intrusions in the Baiyinwula region of the Mongolian Arc. This study revealed that the magmatic sequences evolution includes: (1) early andesites (317–311 Ma) with enrichment in large ion lithophile elements (LILEs), depletion in high field strength elements (HSFEs), and positive zircon εHf (t) values from +9.0 to +15.5, indicating a derivation from enriched mantle; (2) felsic rocks emplaced from 306 Ma to 292 Ma, with relatively lower εHf (t) values from +6.3 to +11.3, implying juvenile crust as the primary magma source; and (3) A-type igneous rocks (280–278 Ma). The comparison of palaeontological, lithostratigraphical, and magmatic evolution in Late Paleozoic between different tectonic units in the eastern part of CAOB has displayed that the subduction of Paleo-Asian oceanic crust caused the opening of the Hegenshan Ocean along the southern margin of Mongolian Arc in Devonian; and the Baoligaomiao Formation volcanic rocks and coeval intrusions have recorded early northwards subduction and subsequent slab rollback of Hegenshan oceanic crust.
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•Baoligaomiao Formation volcanic-sedimentary rocks deposited in Late Carboniferous to Early Permian•Baoligaomiao Formation volcanic rocks and coeval intrusions formed in Andean-type continental margin•Collision between North China Craton and Mongolian arc occur after the early Permian.
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•Late Cretaceous gabbronorites were identified in southwestern Lhasa Terrane.•The subducted Neo-Tethyan sediments were melted under hot and dry conditions.•The Late Cretaceous ...magmatic flare-up was caused by Neo-Tethyan slab roll-back.
The geodynamic processes responsible for the Late Cretaceous magmatic flare-up in the southern Lhasa Terrane, Tibetan Plateau, have been a matter of debate. In this study, we have reported on newly identified Late Cretaceous gabbronorites in the Dajiacuo Area of the southwestern Lhasa Terrane. These rocks show ophitic textures comprising plagioclase, orthopyroxene, and clinopyroxene, while hydrous minerals, such as amphibole and biotite, are not observed. They display geochemical affinities for high-Mg andesites (HMAs) given their SiO2 (53.5–59.7 wt. %), Mg# (56.8–59.9), and Cr (up to 178 ppm). Combined with their high Th/Yb and low Ba/La ratios and similar Sr–Nd–Hf isotopes to those of the Neo-Tethyan sediments, it is likely that the Dajiacuo gabbronorites were formed by the interaction between sediment-derived melts and the mantle. The Dajiacuo gabbronorites have similar Zr/Hf ratios to the Neo-Tethyan sediments and present no negative Zr–Hf anomalies. This indicates that the zircons in the subducted sediments may have been fully destroyed. This requires specific dynamic conditions to provide a hot subduction geothermal gradient. This is consistent with the high-temperature affinity of the parent magma inferred from Ti-in-zircon thermometry and the presence of orthopyroxene. Based on this, coupled with the synthesis of existing tectonomagmatic data for the southern Tibetan Plateau, we propose that the Late Cretaceous magmatic flare-up in the southern Lhasa Terrane was likely triggered by the roll-back of the northwards subducted Neo-Tethyan lithosphere.
This paper addresses the lithosphere-scale subduction–collision history of the eastern termination of the Aegean retreating subduction system, i.e. western Anatolia. Although there is some general ...consensus on the protracted subduction evolution of the Aegean since the early Cenozoic at least, correlation with western Anatolia has been widely debated for more than several decades. In western Anatolia, three main tectonic configurations have been envisaged in the past years to reconstruct slab dynamics during the closure of the Neotethyan oceanic realm since the Late Cretaceous. Some authors have suggested an Aegean-type scenario, with the continuous subduction of a single lithospheric slab, punctuated by episodic slab roll-back and trench retreat, whereas others assumed a discontinuous subduction history marked by intermittent slab break-off during either the Campanian (ca. 75 Ma) or the Early Eocene (ca. 55–50 Ma). The third view implies three partly contemporaneous subduction zones. Our review of these models points to key debated aspects that can be re-evaluated in the light of multidisciplinary constraints from the literature. Our discussion leads us to address the timing of subduction initiation, the existence of hypothetical ocean basins, the number of intervening subduction zones between the Taurides and the Pontides, the palaeogeographic origin of tectonic units and the possibility for slab break-off during either the Campanian or the Early Eocene. Thence, we put forward a favoured tectonic scenario featuring two successive phases of subduction of a single lithospheric slab and episodic accretion of two continental domains separated by a continental trough, representing the eastern end of the Cycladic Ocean of the Aegean. The lack of univocal evidence for slab break-off in western Anatolia and southward-younging HP/LT metamorphism in continental tectonic units (from ~85, 70 to 50 Ma) in the Late Cretaceous–Palaeogene period suggests continuous subduction since ~110 Ma, marked by roll-back episodes in the Palaeocene and the Oligo-Miocene, and slab tearing below western Anatolia during the Miocene.
Oceanic plate subduction can exert extensional, compressional or both types of deformations simultaneously in overriding plates. In this study, we explore the factors controlling these two competing ...modes of deformation in response to contrasting stress fields. Two-dimensional computational fluid dynamics models are presented to show that the dip and age of subducting slabs are crucial parameters to modulate the extensional versus compressional deformations. Shallow-dipping (< 30°) and/or young (< 60 Myr) subducting slabs favor compressional tectonics to form an orogenic wedge (accretionary type), whereas steeply dipping (> 45°) and/or old (> 60 Myr) slabs facilitate extensional tectonics, expressed as a back-arc basin (non-accretionary type). We validate the parametric analysis by comparing our model results with the observed modes of overriding plate deformation in natural subduction zones.
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•Numerical simulations are run to understand the mode of plate margin deformation as a function of subducting slab dip and age.•Shallow and/or young slabs develop accretionary type plate margin while steep and/or old slabs exhibit non-accretionary type.•The model results are in agreement with the styles of plate margin deformation in natural subduction zones.
•The Tongren Pluton was formed in the Middle Triassic (240.5–241.0Ma).•The Tongren granodiorites were generated by magma mixing between mantle- and crustal-derived melts.•The Tongren Pluton formed in ...a subduction regime.
The West Qinling Orogenic Belt (WQOB), an important part of the Qinling-Dabie-Sulu Orogen (Central Orogen), is essential to understand the prolonged evolution of the northeastern branch of the Paleo-Tethys in East Asia. Zircon LA-ICP-MS U–Pb age and Lu–Hf isotopes, bulk-rock major and trace element, and Sr–Nd isotope data for the granodiorite intrusion from the Tongren area, West Qinling are presented. LA-ICP-MS zircon U–Pb dating analyses from two samples constrain the time of crystallization of the granodiorite to ca. 241Ma. Combined with newly published age data from other coeval intrusive rocks in West Qinling, it is concluded that an Early Indosinian magmatic event occurred in West Qinling. In-situ zircon Hf isotope data on the two samples dated exhibit εHf(t) values of −0.6 to −5.8 and −0.8 to −3.9, with corresponding TDMC ages of 1312 to 1637Ma and 1321 to 1516Ma, respectively. Granodiorites are characterized by relatively high Mg# values (51.4–58.0), intermediate SiO2 (63.75–67.04wt.%), high Al2O3 (14.24–15.58wt.%) and total alkalies (6.60–8.00wt.%) and relatively low A/CNK values (0.93–1.10). Granodiorites have I-type, high-K to shoshonitic, and metaluminous to weakly peraluminous character, showing bulk-rock geochemical features of arc-related granitoids. They are enriched in large-ion lithophile and light rare-earth elements, and depleted in some high-field-strength elements. The rocks show uniformly high (87Sr/86Sr)t (0.707616–0.708237) and low εNd(t) values (−7.9 to −7.5). Estimated crystallization temperatures for the rocks range from 720±48°C (Ti-in-zircon thermometer) to 759±25°C (zircon saturation thermometer). The data suggest that magmas were generated by dehydration melting of a mafic lower crustal component with additional input of a mafic component derived from the subcontinental lithospheric mantle. We conclude that the Tongren granodiorite formed in a subduction-related regime in response to slab roll-back of the northward-subducting A’nyemaqen–Mianlue oceanic lithosphere.
The slab dynamic processes, such as roll-back during oceanic subduction and break-off during collision orogenesis, would affect the movement of mantle material and the interaction between crust and ...mantle, accompanied by significant amounts of magmatism. Providing accurate depictions for these processes are extremely difficult, especially in the case of ancient orogens. Here, we present an integrated study of petrology, geochronology, geochemistry and Sr–Nd–Hf isotopes for Early Paleozoic granitoids from the Duojielaka, Ledu and Binglingsi plutons of the southeastern Qilian orogen. Our LA-ICP-MS UPb zircon data show that these granitoids were emplaced at 476–432 Ma. The petrological and geochemical data suggest that the ~476 Ma Duojielaka porphyritic syenogranites formed by feldspar-dominated fractionation from relatively K-rich basaltic rock-derived adakitic parental magma. The ~454 Ma Duojielaka biotite monzogranites are highly fractionated I-type granites and were derived from basement orthogneisses mixed with minor mafic rocks. The Ledu fine- and medium-grained quartz diorites (~446 and ~452 Ma) are high-K calc-alkaline to shoshonitic and were produced by partial melting of relatively old K-rich mafic crust followed by minor mixing with mantle-derived magmas. The ~432 Ma Binglingsi biotite monzogranites with adakitic characteristics most likely originated by partial melting of thickened mafic lower crust. Based on the new data, in combination with previously published data, we suggest that the roll-back of the South Qilian oceanic slab occurred during the Middle Cambrian to early Middle Ordovician. The Duojielaka porphyritic syenogranites represented crustal anatexis in an arc front associated with slab roll-back. The Late Ordovician–early Middle Silurian intrusive rocks probably resulted from diachronous slab break-off in the post-collisional stage. The rocks record the opening of the break-off window from east to west and the gradual heat propagation from the central part to the southern and northern margins of the eastern Central Qilian due to the widening of break-off window and asthenospheric upwelling. We propose that complex geodynamic processes and their thermal effects can be traced by a comprehensive consideration of the petrogenetic, temporal and spatial evolution of related magmatism.
•Genesis of Early Paleozoic granitoids (476–432 Ma) in the eastern Qilian orogen.•Magmas were predominantly derived from diverse crustal sources.•Magma generations were related to slab roll-back and diachronous break-off.•Orogenic geodynamic processes and their thermal effects can be traced by magmatism.
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•The granitoids in East Malaya were emplaced at 289–244 Ma.•The granitoids were formed in response to the Paleotethyan subduction.•The slab roll-back of the Eastern Paleotethyan ...initially occur at ∼ 270 Ma.•Subduction-related granitoids in East Malaya can extend to SW China and W Borneo.
Well-preserved Late Paleozoic–Early Mesozoic igneous rocks in Peninsular Malaysia are important for investigating the Paleotethyan tectonic evolution. This study presents new zircon U-Pb dating, whole-rock geochemical, and Sr-Nd-Pb-Hf isotopic data for granitoids identified from the East Malaya. By utilizing all available data, the Permian–Middle Triassic granitoids in Eastern Peninsular Malaysia can be divided into three groups. Group A (289–270 Ma) I-type granites have higher εNd (t) values of − 6.6 to − 2.6 and zircon εHf (t) values of − 7.1 to + 4.9 than Group B S-type granites (285–272 Ma) with εNd (t) = − 10.1 and zircon εHf (t) = − 23.1 to + 1.5. Group C (254–244 Ma) with A-type characteristics, has εNd (t) and zircon εHf (t) values ranging from − 7.3 to − 3.8 and − 8.9 to + 2.2, respectively. The Pb isotopic values for three groups are similar with (206Pb/204Pb)i = 18.71–19.43, (207Pb/204Pb)i = 15.66–15.71 and (208Pb/204Pb)i = 38.27–39.43. Group A was derived from metaigneous rocks with a juvenile mafic component, while Group B was from metasedimentary rocks. Group C had a mixed source of “ancient” meta-mafic rocks with a juvenile mafic component. This study proposes that the Late Paleozoic–Early Mesozoic granitoids were formed in response to the subduction of the Paleotethyan Ocean, and that a tectonic transition from subduction to slab roll-back might occur at ∼ 270 Ma. Subduction-related granitoids in East Malaya can northernly extend to the Tachileik Batholith in eastern Myanmar and Jinghong in SW China, and southernly link with W Borneo.
Purpose
Kinematically aligned total knee arthroplasty is associated with superior pain relief, increased flexion and a more normal feeling knee. It was hypothesized that due to restoring the knee’s ...natural anatomy, kinematically aligned knees show more physiological tibiofemoral kinematics than mechanically aligned knees.
Methods
Investigations were performed in nine healthy cadaveric knees of whole bodies fixed by the Thiel method. Tibiofemoral kinematics of healthy knees and after kinematically and mechanically aligned total knee arthroplasty were assessed between 0° and 90° of flexion by a navigational device.
Results
Regarding tibial internal rotation or femoral roll back, respectively, kinematically aligned total knee arthroplasties showed no significant differences between 0° and 70° of flexion in comparison to knees before total knee arthroplasty. In contrast, mechanically aligned total knee arthroplasties showed significant changes between 10° and 90° of flexion. Kinematically aligned knees showed a significant changed abduction/adduction between 20° and 70° of flexion, mechanically aligned knees within 20° and 90° of flexion.
Conclusion
In the present study setting kinematically aligned total knee arthroplasties showed more natural and physiological tibiofemoral kinematic pattern with regard to tibial internal rotation or femoral rollback, respectively, and tibial adduction than mechanically aligned total knee arthroplasties. While these results may support promising early clinical results of kinematical alignment proposing a better function, long-term results especially implant survival need to be awaited.
