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Most metal-organic frameworks(MOFs) hardly maintain their physical and chemical properties after exposure to acidic,neutral,or alkaline aqueous solutions,resulting in insufficient stability,therefore limiting their applications.Thus,the design and synthesis of stable size/morphology-controlled MOF nanocrystals is critical but challenging.In this study,dual-ligand and hard-soft-acid-base strategies were used to fabricate a variety of 3D pillared-layer [Ni(thiophene-2,5-dicarboxylate)(4,4’-bipyrid...  相似文献   

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As early as 2001,the need for the ’functional motif theory’ was pointed out,to assist the rational design of functional materials.The properties of materials are determined by their functional motifs and how they are arranged in the materials.Uncovering functional motifs and their arrangements is crucial in understanding the properties of materials and rationally designing new materials of desired properties.The functional motifs of materials are the critical microstructural units(e.g.constituen...  相似文献   

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High-nuclear lanthanide clusters have shown great potential for the administration of high-dose mononuclear gadolinium chelates in magnetic resonance imaging(MRI). The development of high-nuclear lanthanide clusters with excellent solubility and high stability in water or solution has been challenging and is very important for expanding the performance of MRI. We used N-methylbenzimidazole-2-methanol(HL) and LnCl3·6H2O to synthesize two spherical lanthanide clusters, Ln  相似文献   

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Lipiodol chemotherapeutic emulsions remain one of the main choices for the treatment of unresectable hepatocellular carcinoma(HCC) via transarterial chemoembolization(TACE). However, the limited stability of Lipiodol chemotherapeutic emulsions would lead to rapid drug diffusion, which would reduce the therapeutic benefit and cause systemic toxicity of administrated chemotherapeutics. Therefore, the development of enhanced Lipiodol-based formulations is of great significance to enable effective a...  相似文献   

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Wireless power transfer(WPT) technology based on magnetic resonance(a basic physical phenomenon)can directly transfer energy from the source to the load without wires and other physical contacts, and has been successfully applied to implantable medical devices, electric vehicles, robotic arms and other fields.However, due to the frequency splitting of near-field coupling, the resonant WPT system has some unique limitations, such as poor transmission stability and low efficiency. Here, we propose...  相似文献   

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Although molecular imaging probes have the potential to non-invasively diagnose a tumor,imaging probes that can detect a tumor and simultaneously identify tumor malignancy remain elusive.Here,we demonstrate a potassium ion(K+) sensitive dual-mode nanoprobe(KDMN) for non-invasive tumor imaging and malignancy identification,which operates via a cascaded ’AND’ logic gate controlled by inputs of magnetic resonance imaging(MRI) and fluorescence imaging(FI) signals.We encapsulate commercial K+  相似文献   

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The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and intr...  相似文献   

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Although pure formamidinium iodide perovskite(FAPbI3) possesses an optimal gap for photovoltaics,their poor phase stability limits the long-term operational stability of the devices.A promising approach to enhance their phase stability is to incorporate cesium into FAPbI3.However,state-of-the-art formamidinium-cesium(FA-Cs) iodide perovskites demonstrate much worse efficiency compared with FAPbI3,limited by the different crystallization dynamics of formamidinium ...  相似文献   

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Outgassing of carbon dioxide from the Earth’s interior regulates the surface climate through deep time.Here we examine the role of cratonic destruction in mantle CO2 outgassing via collating and presenting new data for Paleozoic kimberlites, Mesozoic basaltic rocks and their mantle xenoliths from the eastern North China Craton(NCC), which underwent extensive destruction in the early Cretaceous. High Ca/Al and low Ti/Eu and δ26 Mg are widely observed in lamprophyres and mant...  相似文献   

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Tracing the closure of oceans with irregular margins and the formation of an orocline are crucial for understanding plate reconstruction and continental assembly.The eastern Central Asian Orogenic Belt,where the Mongol-Okhotsk orocline is situated,is one of the world’s largest magmatic provinces.Using a large data set of U-Pb zircon ages,we updated the timing of many published igneous rocks,which allowed us to recognize tightly ’folded’ linear Carboniferous-Jurassic magmatic belts that wrap arou...  相似文献   

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<正>Zeolites are crystalline microporous solids whose frameworks are composed of corner-sharing tetrahedral TO4 units (T=Si,Al, P, etc.), forming periodic one-dimensional (1D) to threedimensional (3D) channels with an aperture size of typically<2 nm. Because of their unique pore structures, large specific surface area, strong acid sites, high thermal/hydrothermal stability and molecular-level shape selectivity, zeolites are widely used as catalysts, adsorbents and ion exchangers in the f...  相似文献   

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<正>Recently,the search for novel two-dimensional (2D) organic-inorganic halide perovskite materials has come to a renaissance.There is significant interest not only in terms of their intriguing optoelectronic properties,but also their structural diversity and improved stability.The 2D perovskite structure can be visualized as atomically thin slabs cut from 3D parent structures along different crystal directions that are sandwiched between two layers of large organic cations.The bulky organ...  相似文献   

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The degradation of plastics has attracted much attention from the global community.Polyethylenes(PEs),as the most abundant synthetic plastics,are most frequently studied.PE is non-degradable and non-polar because of the sole presence of the pure hydrocarbon components.Concurrent incorporation of both in-chain cleavable and functional groups into the PE chain is an effective pathway to overcome the non-degradable and non-polar issue;however,the method for achieving this pathway remains elusive.He...  相似文献   

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Dams are often regarded as greenhouse gas(GHG) emitters. However, our study indicated that the world’s largest dam, the Three Gorges Dam(TGD), has caused significant drops in annual average emissions of CO2, CH4 and N2O over 4300 km along the Yangtze River, accompanied by remarkable reductions in the annual export of CO2(79%), CH4(50%) and N2O(9%) to the sea. Since the commencement of its operation in 2003, the TGD has altered the...  相似文献   

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<正>After eons of evolution,biological systems have developed excellent performance in terms of sensing,intelligence,and actuation—the three primary robotics elements that are closely related to the overall performance of robot systems.For example,the buccal pits of some snakes,as the necessary sensors for accurate predation,have a high-temperature sensitivity of 0.003 K[1];  相似文献   

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<正>One year after China launched its first dedicated space telescope to study the Sun, the Advanced Space-based Solar Observatory(ASO-S) is now fine-tuned and ready for discoveries during the activity peak of this solar cycle. ‘ASO-S has completed its in-orbit tests, and all instruments are in stable operation. Some early results are already in the pipeline,’ said the mission’s chief scientist, Gan Weiqun, as the telescope was officially delivered to his co-workers at the Purple Mountain O...  相似文献   

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<正>Noise-induced hearing loss (NIHL) is one of the most common types of hearing loss and contributes to significant morbidity worldwide,as well as being the major cause of age-related hearing loss and tinnitus.The World Health Organization (WHO) estimates that 10%of the world’s population is exposed to sound levels that could potentially cause NIHL[1].It has been widely accepted that NIHL is a multifactorial genetic disorder with estimated heritability of 36%to 40%[2].Ideally,identificatio...  相似文献   

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