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Carbonate rocks, widely used for quantifying paleolatitude of the Gondwana‐derived terranes on the Tibetan Plateau and the geodynamic evolution of the Tethyan Oceans, are prone to remagnetization. However, diagnosing such secondary remanent magnetization is difficult and the mistakes have induced confusion in paleogeographic reconstructions. To evaluate if the Upper Triassic limestones of the Duoburi Formation from the Lhasa terrane carry a primary remanence, we report comprehensive rock magnetic, diffuse reflectance spectroscopic, and petrographic results of these rocks. We discover that magnetic carriers vary systematically from magnetite to magnetite plus minor hematite/goethite to hematite/goethite plus minor magnetite with change of rock color and demagnetization behavior of the specimens. Most magnetite and all hematite/goethite grains have clear authigenic origin and were possibly formed during oxidation of early diagenetic pyrite. Such a process was likely assisted by oxic fluid circulation as shown by omnipresent calcite veins within the rocks. These authigenic iron oxides have widely distributed grain sizes with most of them being superparamagnetic at room temperature. Detrital (titano)magnetite is also recognized in some specimens, but its concentration is much lower than that of the authigenic magnetic grains. Based on these results, we conclude that limestone from the Duoburi Formation was remagnetized due to fluid circulation during late diagenesis. We discuss criteria used for diagnosing remagnetization in carbonate rocks, and suggest that a robust evaluation of the remanence origin should integrate field tests, statistics of the remanence direction, rock magnetic properties, and petrographic observations with the limits of each criterion being carefully considered. Plain Language Summary: The Lhasa terrane from the central Tibetan Plateau was one of the continental blocks that rifted from the Gondwana supercontinent, drifted northward, and accreted to Eurasia in the Mesozoic. Paleolatitude determined by paleomagnetism can provide quantitative information which is critical to restore these geodynamic processes. However, paleomagnetic investigations on the ancient carbonate rocks on the Tibetan Plateau are often troubled by remagnetization, a process during which the primary remanent magnetization acquired during or soon after formation of the rocks was replaced by secondary remanent magnetization with an unknown younger age. In this study, we provide an example of Upper Triassic limestones from the Lhasa terrane. Within these rocks, detrital (titano)magnetite, which can carry a primary magnetic signal, was mostly altered, and nonmagnetic pyrite largely transformed to authigenic magnetite/hematite/goethite, which acquired remanent magnetization at an unknown later time. The magnetic record from these rocks thus cannot be used to determine the Late Triassic paleolatitude of the Lhasa terrane. Our analysis reveals the most common mechanisms of remagnetization in carbonate rocks. More importantly, we provide universal tools and criteria that can be used in future paleomagnetic studies of carbonate rocks to evaluate their remanence origin. Key Points: Magnetic carriers of the Duoburi Formation limestone are authigenic magnetite, hematite and goethite and little detrital titanomagnetiteLimestones of the Duoburi Formation were remagnetized due to circulation of oxic fluid through the rock at a late stageDiagnosis of remagnetization in carbonate rocks should integrate different criteria but consider the limits of each criterion carefully [ABSTRACT FROM AUTHOR]

Open wounds infected by bacteria are gearing increasing attention whose treatment are complicated by the appearance of multidrug‐resistant bacteria. Photothermal therapy, kill bacteria through the photothermal conversion, has been extensively studied. Whereas, the high cost and low yield of the active ingredients have limited its widespread use. To address this challenge, the template assisted coating strategy was adopted to prepare a biocompatible photothermal agent, where the hybrid was prepared via in situ copolymerization of 5,10,15,20‐tetrakis(4‐ethynylphenyl)‐21H,23H‐porphine (Por) on the surface of ZIF‐8 template. The introduction of ZIF‐8 in the inner of the hybrid, could not only lower the cost of photosensitizer (i. e., the porphyrin), but also maintain the activity of photosensitizer (PS) finely, which could be used directly as the antimicrobial dressing. In vitro experiments validated the as‐prepared hybrid presents high‐efficiency PTT antibacterial activity. Meanwhile, in vivo chronic wound‐healing experiments on mice verified the as‐synthesized hybrid also delivers excellent anti‐infection and tissue remodeling activities. This work highlights the potential of low‐cost hybrid‐based multifunctional biomaterials in the treatment of skin injuries in clinical settings. [ABSTRACT FROM AUTHOR]

The paleogeography of the Tethyan Himalaya (TH) during the Mesozoic is vital to constrain the evolutionary history of the Neo‐Tethys Ocean, but reliable paleomagnetic data from Jurassic rocks in this area are scarce. Here, we report the first high‐quality paleomagnetic results from the Middle Jurassic (∼175–173 Ma) Lanongla Formation limestones in the Nyalam area of the TH. For most specimens, stepwise thermal or hybrid demagnetization reveals two well‐defined magnetization components. A low‐temperature component, which is isolated between natural remanent magnetization and 200–300°C, is consistent with the present geomagnetic field direction. A high‐temperature component, which is isolated between 300–350°C/10–25 mT and 500–580°C/60–120 mT, passes fold tests at the 95% and 99% confidence level, indicating a prefolding primary magnetization. The tilt‐corrected site‐mean direction for 28 paleomagnetic sites is Ds = 331.0° and Is = −49.9° with α95 = 2.7°, which provides a Fisherian site‐mean paleopole at 23.7°N, 292.9°E with A95 = 2.8° and a paleolatitude of 31.7 ± 2.8°S for the Nyalam study area (28.6°N, 86.1°E). A comparison between the reliable Middle Jurassic‐Early Cretaceous poles obtained from the TH and those observed from the Lhasa terrane reveals that the Neo‐Tethys Ocean for the reference point (29.1°N, 86.1°E) had a latitudinal width of 3,500 ± 1,000 km at ∼174 Ma, reached its greatest width of 7,000 ± 1,000 km at ∼137 Ma, and had an average latitudinal spreading rate of ∼10.4 cm/year during ∼174–137 Ma. Plain Language Summary: The Neo‐Tethys Ocean here refers to the prehistoric ocean that existed between the Lhasa terrane to the north and the Indian plate to the south during the much of the Mesozoic and early Cenozoic. Knowledge of the development of the Neo‐Tethys Ocean is crucial to understanding the evolution of the Himalayas and Tibetan Plateau. However, the opening of the Neo‐Tethys Ocean remains controversial. In this work, we report what we consider is the first high‐quality Middle Jurassic age paleopole from the Tethyan Himalaya, which shows that the Nyalam area was located at 31.7 ± 2.8°S at ∼174 Ma and that the Neo‐Tethys Ocean was at least ∼3,500 km wide in a N–S direction at that time. Key Points: The Nyalam area of the Tethyan Himalaya (TH) was located at 31.7 ± 2.8°S at ∼174 MaThe Neo‐Tethys Ocean opened a latitudinal width of ∼3,500 km at ∼174 Ma and reached its greatest width of ∼7,000 km at ∼137 MaThe Neo‐Tethys Ocean had an average latitudinal spreading rate of ∼10.4 cm/year during ∼174–137 Ma [ABSTRACT FROM AUTHOR]

The drift history of the Lhasa terrane is crucial for understanding the tectonic evolution of Tethyan Oceans and Jurassic true polar wander. However, high‐quality Middle Jurassic paleomagnetic data from the Lhasa terrane are limited in number. Here we report a combined paleomagnetic and geochronologic study on the Yeba Formation volcanic rocks, dated at ∼170 Ma, from the Lhasa terrane. Robust field and reversal tests indicate that the characteristic remanent magnetizations are primary. Our results provide a reliable Middle Jurassic (∼170 Ma) paleopole at 29.8°N, 180.7°E with A95 = 5.7° and a paleolatitude of 14.4 ± 5.7°N for the Lhasa area. Compared with previous paleomagnetic and geologic evidence, we propose that the Meso‐Tethys Ocean probably began to close in the eastern part at ∼168 Ma and that the Lhasa terrane underwent a ∼2,900 km southward "monster shift" during the Late Jurassic. Plain Language Summary: The formation of the Tibetan Plateau followed the breakup of the Gondwana supercontinent and was associated with the demise of several Tethyan Oceans. The Lhasa terrane, which is a long and narrow continental fragment derived from Gondwana, was isolated in the Tethyan Ocean during the Jurassic and finally accreted to the south margin of the Paleo‐Asia continent, leading to the closure of the Meso‐Tethys Ocean. However, when this Meso‐Tethys Ocean closed is still controversial. Our new robust paleomagnetic result shows that the Lhasa terrane was located at ∼14.4°N at ∼170 Ma. Based on available reliable Jurassic paleomagnetic data from the eastern part of the Lhasa and Qiangtang terranes, we suggest that the Meso‐Tethys Ocean began to close in the eastern part at ∼168 Ma. Integrating our critical Middle Jurassic paleomagnetic data with that of the Late Jurassic from the Lhasa terrane, we argue that the Lhasa terrane suffered a ∼2,900 km southward latitudinal shift during the Late Jurassic, which is known as true polar wander. Key Points: The Lhasa terrane was located at ∼14.4 ± 5.7°N at ∼170 MaThe Lhasa terrane experienced a ∼2,900 km southward monster shift during the Late JurassicThe closure of the Meso‐Tethys Ocean in the eastern part most likely occurred at ∼168 Ma [ABSTRACT FROM AUTHOR]

The timing and location India–Asia collision is crucial to understanding the evolution of the Himalayan–Tibetan orogen and global climate change; however, estimates of the timing of the India–Asia collision and the size of Greater India remain highly controversial. We report here the first reliable early Eocene paleomagnetic results from the Zhepure Formation limestone in the Tethyan Himalaya (TH). Both positive fold and reversal tests indicate a primary origin. The tilt‐corrected site‐mean direction is Ds = 332.6°, Is = 20.1°, ks = 90.9, α95 = 2.8° (N = 30). The site‐mean inclination increased from 20.1° to 27.5° after inclination shallowing correction, yielding a paleopole at 61.2°N, 337.3°E, A95 = 2.6° and a corresponding paleolatitude of 15.2° ± 2.6°N for the reference point (29.5°N, 91.0°E). Our new paleomagnetic results, together with the reliable Cretaceous to Paleogene paleomagnetic results from the TH, Lhasa terrane and Indian craton, suggest that there was ∼900–1,140 km north‐south crustal shortening occurred between the TH and the Indian craton, and that India collided with Asia at no later than ∼51–49.5 Ma. Plain Language Summary: The India–Asia collision is among the most intriguing topics in earth sciences because of its influence on global climate and Cenozoic topography. However, several questions still remain unanswered, such as: how big was Greater India? When, where, and how did the India collide with Asia? We report the first reliable early Eocene paleopole from the TH and assess the timing of the India–Asia collision and the size of Greater India. Our results suggest a relatively small Greater India, and that India collided with Asia at no later than ∼51–49.5 Ma. The constraints on the India–Asia collision indicated by our data provide new boundary conditions for the history of the Himalayan–Tibetan orogen and global climate change. Key Points: The Tethyan Himalaya (TH) was located at 15.2° ± 2.6°N at ∼51–49.5 MaThere was ∼900–1,140 km north‐south crustal shortening occurred between the TH and the Indian cratonIndia collided with Asia at no later than ∼51–49.5 Ma [ABSTRACT FROM AUTHOR]

In this manuscript, we checked all the pieces of evidence separately and conclude that the evidence Zhao et al. (2021, https://doi.org/10.1029/2020TC006520) provided cannot be regarded as arguments supporting their points. Our observations show that (i) sampling units and depositional environment support that the Jingzhushan Formation red beds could be affected by the syntectonic sedimentation, (ii) characteristic remanent magnetization directions observed from the Jingzhushan Formation red beds represent primary magnetization acquired during the syntectonic sedimentation, not secondary remagnetization due to strain reorientation of remanence, and (iii) inclination discrepancy of the Jingzhushan Formation red beds could be attributed to syntectonic sedimentation. Therefore, the paleomagnetic results obtained from the Jingzhushan Formation red beds are reliable for paleogeographic reconstructions. Key Points: Characteristic remanent magnetization directions observed from the Jingzhushan Formation red beds represent primary magnetizationPaleomagnetic data obtained from two limbs of the folded Jingzhushan Formation red beds are reliable for paleogeographic reconstructionsSyntectonic sedimentation is a reasonable interpretation for the inclination discrepancy of the Jingzhushan Formation red beds [ABSTRACT FROM AUTHOR]

The precollisional locations and geometries of the Lhasa terrane (LT) are critical to constrain the India‐Asia collision. However, the inclinations of the Cretaceous paleomagnetic data obtained from the northern limb of folds are obviously lower than those obtained from the southern limb, which cause large discrepant paleolatitudes of the LT prior to India‐Asia collision. Here, we carried out a new paleomagnetic investigation on the Late Cretaceous Jingzhushan Formation red beds in the far western LT. The tilt‐corrected site mean direction yielded a palaeopole at 74.4°N, 226.0°E with A95 = 3.8° (N = 54). This paleomagnetic data set passes fold tests and indicates that the studied area was located at 19.6° ± 3.8°N during the Late Cretaceous. However, the mean inclination calculated from the northern limb of folds (Is = 19.0°) is significantly lower than that of the southern limb of folds (Is = 51.8°). This inclination discrepancy of the Jingzhushan Formation red beds may be attributed to the syntectonic sedimentation. Nevertheless, the site mean direction obtained from both limbs of folds is generally consistent with the site mean direction after syntectonic‐sedimentation correction. Our new paleomagnetic results, combined with the reliable Cretaceous paleomagnetic results from the LT showed that the southern margin of Asia had a present‐day relatively east‐west alignment prior to India‐Asia collision. Key Points: A new paleopole (74.4°N, 226.0°E with A95 = 3.8°) was obtained from the Jingzhushan Formation red beds in the far western Lhasa terraneInclination discrepancy of the Jingzhushan Formation red beds may be attributed to the syntectonic sedimentationThe southern margin of Asia had a present‐day relatively east‐west alignment prior to India‐Asia collision [ABSTRACT FROM AUTHOR]

Cyclotriphosphazene (CP) based porous organic polymers (POPs) have been designed and prepared. The introduction of CP into the porous skeleton endowed special thermal stability and outstanding flame retardancy to prepared polymers. The nonflammable level of PNK‐CMP fabricated via the condensation of 2,2′‐(1,4‐phenylene)diacetonitrile (DAN) and hexakis(4‐acetylphenoxy)cyclotriphosphazene (HACTP) through Knoevenagel reaction, in vertical burning tests reached V‐2 class (UL‐94) and the limiting oxygen index (LOI) reached 20.8 %. When used as additive, PNK‐CMP could suppress the dissolving out of PEPA effectively, reducing environment pollution and improving the flame retardant efficiency. The POP and PEPA co‐added PU (mPOP%: mPEPA%=5.0 %: 5.0 %) could not be ignited under simulated real‐scale fire conditions. The nonflammable level of POP/PEPA/PU in vertical burning tests (UL‐94) reached V‐0 class with a LOI as high as 23.2 %. The smoke emission could also be suppressed, thus reducing the potential for flame spread and fire hazards. Furthermore, carbonization of PNK‐CMP under the activation of KOH yield a hyperporous carbon (PNKA‐800) with ultrahigh BET surface area (3001 m2 g−1) and ultramicropore size showing excellent ORR activity in alkaline conditions. [ABSTRACT FROM AUTHOR]

The precollisional paleolatitude of the Tethyan Himalaya is essential to constrain the India‐Asia collision, the size of Greater India, and the Neotethyan paleogeography. However, reliable Late Cretaceous‐Paleocene paleomagnetic datasets are still scarce because of serious remagnetization. Here we report the first redbed‐based paleomagnetic results from the Paleocene (60‐58 Ma) redbeds in the Saga area of the northern Tethyan Himalaya. The tilt‐corrected site‐mean direction obtained from 36 paleomagnetic sites is D=178.7°, I=9.5° with ɑ95=5.4°, corresponding to a paleopole at 55.9°N, 267.6°E with dp/dm=2.8°/5.5° and a paleolatitude of 4.8°±2.8°S for the study area (29.3°N, 85.3°E). The site‐mean inclination increased from 9.5 to 14.9° after the anisotropy‐based inclination shallowing correction, leading to corresponding paleolatitudes increasing from 4.8 to 7.6°S. This reliable paleomagnetic dataset passes positive fold tests and supports that the northern Tethyan Himalaya was located at 6.3±4.3°S during 60‐58 Ma. Comparison with the coeval paleolatitudes expected from the Indian craton indicates that a north‐south crustal shortening of 3.1±5.5° (340±610 km) occurred between the Indian craton and the northern Tethyan Himalaya after 59 Ma, and no wide ocean extended between them after the Latest Jurassic. Our new Paleocene results together with reliable Cretaceous paleomagnetic results from the Lhasa terrane show that the India‐Asia collision occurred at 47.1±4.5 Ma. Key Points: The Saga area of the northern Tethyan Himalaya at ~59 Ma lay at 6.3°±4.3°SNeither wide Ocean extension nor >1,000 km crustal shortening occurred between Indian craton and Tethyan Himalaya after the latest JurassicThe India‐Asia collision occurred at 47.1±4.5 Ma [ABSTRACT FROM AUTHOR]

The breakup of eastern Gondwana is among the hottest topics in the Earth sciences because of its effect on global climate during the Jurassic‐Cretaceous, its influence on the evolution of life, and its importance to paleogeographic reconstruction. To better constrain the Jurassic and Cretaceous paleogeographic position of the Tethyan Himalaya and the breakup of eastern Gondwana, a combined paleomagnetic and geochronological study was performed on the Zhela and Weimei Formations lava flows, dated at ~138–135 Ma, in the Luozha area of the eastern Tethyan Himalaya. Both positive fold and reversal tests together with a maximum grouping at 100% unfolding indicate that the characteristic remanent magnetization directions are primary magnetizations acquired before folding. The tilt‐corrected directions yielded a paleopole at 0.9°N, 293.4°E with A95 = 7.0° and a corresponding paleolatitude of 53.5°S ± 7.0°S for the Luozha sampling area (28.9°N, 91.3°E), validating that the original erupted position of the Zhela and Weimei Formations lava flows was located in the center of the Kerguelen mantle plume. Our new results, together with the published paleomagnetic, geochronological, and geochemical results, demonstrate that the Comei‐Bunbury large igneous province originated from the Kerguelen mantle plume. The temporal and spatial relationships between the Comei‐Bunbury large igneous province and the Kerguelen mantle plume indicate that eastern Gondwana initially rifted at ~147 Ma and that the Indian Plate fully separated from the Australian‐Antarctic Plate before ~124 Ma. Key Points: The Luozha sampling area was located at ~53.5 degrees south plus‐minus 7.0 degrees south at ~138‐135 MaThe Comei‐Bunbury large igneous province (LIP) originated from the Kerguelen mantle plumeEastern Gondwana initially rifted at ~147 Ma, and the Indian Plate fully separated from the Australian‐Antarctic Plate before ~124 Ma [ABSTRACT FROM AUTHOR]

The timing of the north‐south collision between two terranes can be determined by the overlap of their paleolatitudes or the change of their convergence rate. For example, the overlapping paleolatitudes of the Lhasa terrane and Tethyan Himalaya and the dramatic decrease in the velocity of the Indian plate are usually ascribed to the India‐Asia collision at ~55 Ma. However, little is known about the paleolatitudinal evolution and velocity change of the Lhasa terrane resulting from the Lhasa‐Qiangtang collision during the Jurassic‐Cretaceous period. To better constrain the velocity change of the Lhasa terrane during this period, to constrain when and where the Lhasa‐Qiangtang collision occurred, and to assess the distribution of land and sea in the Tethyan realm, we provide a high‐quality Cretaceous paleomagnetic pole obtained from the limestone from the western part of the Lhasa terrane, which yields a paleolatitude of ~16.8° ± 1.9°N for the sampling area (32.2°N, 80.8°E) during the time interval of ~113–72 Ma. We compile existing paleomagnetic results from the Lhasa terrane, Qiangtang terrane, Tethyan Himalaya, and India and reveal that the Lhasa‐Qiangtang collision most likely occurred at or near the J/K boundary at ~19°N for the reference point at (32°N, 88°E) and that the Neo‐Tethys reached its maximum width (≥~7450 km) during this period. Key Points: The Shiquanhe sampling area was located at ~16.8° ± 1.9°N at ~113‐72 MaThe Lhasa‐Qiangtang collision most likely occurred at ~19°N at or near the J/K boundaryThe Neo‐Tethys reached its maximum width (≥~7450 km) during this period [ABSTRACT FROM AUTHOR]

To position the Asian southern margin before the India-Asia collision, paleomagnetic and geochronologic studies were performed on the Dianzhong Formation lava flows from the Shiquanhe area of the westernmost Lhasa terrane (LT). Zircon U-Pb analyses dated the lava flows to ~69.5 ± 2.5 Ma. The characteristic remanent magnetization directions contain antipodal polarities and pass fold tests, implying that they are primary magnetizations; this interpretation is supported by rock-magnetic analyses and petrographic observations. Forty-four site-mean directions were divided into 17 statistically independent direction groups. The group-mean direction after tilt correction is Ds = 43.3°, Is = 30.3°, k = 28.0, α95 = 6.9°. The corresponding paleopole at 47.8°N, 181.4°E ( A95 = 6.4°) yields a paleolatitude of 16.6° ± 6.4°N for the Shiquanhe area of westernmost Tibet (32.34°N, 80.12°E). Consistent paleolatitudes for the southern margin of the LT calculated from the western and central part of the LT indicate that the leading edge of the LT was aligned relatively W-E. When compared with the reference pole at 70 Ma for Eurasia, this new paleopole suggests that crustal shortening between the Shiquanhe area and stable Asia was 1,500 ± 800 km. This is supported by the crustal shortening (600-1,000 km) absorbed by Cenozoic thrust and fold belts within this area, indicating that the magnitude of crustal shortening within Asia north of the India-Asia suture zone was similar in the central and western part of the plateau. [ABSTRACT FROM AUTHOR]

The article presents a study which analyses the new Zircon SHRIMP U-Pb ages of the Langjiu formation volcanic rocks in the Shiquanhe Area in Western Lhasa Terrane. Topics include distribution of potassic and ultrapotassic rocks, geochronological study on the Langjiu Formation volcanic rocks, and magmatic activity of the Linzizong group volcanic rocks.