28 research outputs found

    Anthropogenic Activities Generate High-Refractory Black Carbon along the Yangtze River Continuum

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    12 pages, 7 figuresCombustion-driven particulate black carbon (PBC) is a crucial slow-cycling pool in the organic carbon flux from rivers to oceans. Since the refractoriness of PBC stems from the association of non-homologous char and soot, the composition and source of char and soot must be considered when investigating riverine PBC. Samples along the Yangtze River continuum during different hydrological periods were collected in this study to investigate the association and asynchronous combustion drive of char and soot in PBC. The results revealed that PBC in the Yangtze River, with higher refractory nature, accounts for 13.73 ± 6.89% of particulate organic carbon, and soot occupies 37.53 ± 11.00% of PBC. The preponderant contribution of fossil fuel combustion to soot (92.57 ± 3.20%) compared to char (27.55 ± 5.92%), suggested that fossil fuel combustion is a crucial driver for PBC with high soot percentage. Redundancy analysis and structural equation modeling confirmed that the fossil fuel energy used by anthropogenic activities promoting soot is the crucial reason for high-refractory PBC. We estimated that the Yangtze River transported 0.15–0.23 Tg of soot and 0.15–0.25 Tg of char to the ocean annually, and the export of large higher refractory PBC to the ocean can form a long-term sink and prolong the residence time of terrigenous carbonThis study was supported by grants from the National Natural Science Foundation of China (nos. 42277214, 42207256, and 41971286), major programs of the National Social Science Foundation of China (grant nos. 22&ZD136), the Special Science and Technology Innovation Program for Carbon Peak and Carbon Neutralization of Jiangsu Province (grant no. BE2022612)Peer reviewe

    Application of Virtual Environment in the Teaching of Basketball Tactics

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    The traditional experience basketball teaching method can only master the technical essentials through repeated practice, which seriously affects the ef-ficiency of basketball training. Based on this problem, a basketball teaching simulation system was constructed by using virtual reality technology. The system established a virtual simulation model of basketball players, which planed the track of athletes. In the meanwhile, it captured the real situation of basketball players and contrasted them with simulated trajectories, so as to help athletes do more targeted training. The results showed that basketball technology teaching model based on virtual reality could help athletes grasp the key points of motion skills as soon as possible, and greatly improve the training efficiency of basketball players

    Application of Virtual Environment in the Teaching of Basketball Tactics

    No full text
    The traditional experience basketball teaching method can only master the technical essentials through repeated practice, which seriously affects the ef-ficiency of basketball training. Based on this problem, a basketball teaching simulation system was constructed by using virtual reality technology. The system established a virtual simulation model of basketball players, which planed the track of athletes. In the meanwhile, it captured the real situation of basketball players and contrasted them with simulated trajectories, so as to help athletes do more targeted training. The results showed that basketball technology teaching model based on virtual reality could help athletes grasp the key points of motion skills as soon as possible, and greatly improve the training efficiency of basketball players

    Application of Virtual Environment in the Teaching of Basketball Tactics

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    Nano-CaCO3 synthesis by jet-reactor from calcium carbide slag

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    Nano-CaCO _3 was producted by using carbide slag in the self-designed jet-reactor. The effect of different operating parameter such as CO _2 flow rate and concentration, liquid flow rate and concentration of Ca(OH) _2 on the CaCO _3 particle size and morphology has been investigated in this paper. The obtained calcite particle were characterized using x-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the calcite about 50–200 nm was obtained under the reaction conditions of the saturation of calcium hydroxide as 1, the flow rate as 1.5 l min ^−1 , the CO _2 flow rate as 50 ml min ^−1 , the concentration as 100%, and the SDS amount 2%

    DNA Nanotechnology Enters Cell Membranes

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    Abstract DNA is more than a carrier of genetic information: It is a highly versatile structural motif for the assembly of nanostructures, giving rise to a wide range of functionalities. In this regard, the structure programmability is the main advantage of DNA over peptides, proteins, and small molecules. DNA amphiphiles, in which DNA is covalently bound to synthetic hydrophobic moieties, allow interactions of DNA nanostructures with artificial lipid bilayers and cell membranes. These structures have seen rapid growth with great potential for medical applications. In this Review, the current state of the art of the synthesis of DNA amphiphiles and their assembly into nanostructures are first summarized. Next, an overview on the interaction of these DNA amphiphiles with membranes is provided, detailing on the driving forces and the stability of the interaction. Moreover, the interaction with cell surfaces in respect to therapeutics, biological sensing, and cell membrane engineering is highlighted. Finally, the challenges and an outlook on this promising class of DNA hybrid materials are discussed

    Ultrasound‐controlled drug release and drug activation for cancer therapy

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    Abstract Traditional chemotherapy suffers from severe toxicity and side effects that limit its maximum application in cancer therapy. To overcome this challenge, an ideal treatment strategy would be to selectively control the release or regulate the activity of drugs to minimize the undesirable toxicity. Recently, ultrasound (US)‐responsive drug delivery systems (DDSs) have attracted significant attention due to the non‐invasiveness, high tissue penetration depth, and spatiotemporal controllability of US. Moreover, the US‐induced mechanical force has been proven to be a robust method to site‐selectively rearrange or cleave bonds in mechanochemistry. This review describes the US‐activated DDSs from the fundamental basics and aims to present a comprehensive summary of the current understanding of US‐responsive DDSs for controlled drug release and drug activation. First, we summarize the typical mechanisms for US‐responsive drug release and drug activation. Second, the main factors affecting the ultrasonic responsiveness of drug carriers are outlined. Furthermore, representative examples of US‐controlled drug release and drug activation are discussed, emphasizing their novelty and design principles. Finally, the challenges and an outlook on this promising therapeutic strategy are discussed

    DNA hybridization as a general method to enhance the cellular uptake of nanostructures

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    The biomedical application of nanoparticles (NPs) for diagnosis and therapy is considerably stalled by their inefficient cellular internalization. Many strategies to overcome this obstacle have been developed but are not generally applicable to different NP systems, consequently underlining the need for a universal method that enhances NP entry into cells. Here we describe a method to increase NP cellular uptake via strand hybridization between DNA-functionalized NPs and cells that bear the respective complementary sequence incorporated into the membrane. By this, the NPs bind efficiently to the cellular surface enhancing internalization of three completely different NP types: DNA tetrahedrons, gold (Au) NPs, and polystyrene (PS) NPs. We show that our approach is a simple and generalizable strategy that can be applied to virtually every functionalizable NP system

    Electrical tunable topological valley photonic crystals for on-chip optical communications in the telecom band

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    On-chip optical communications are in increasingly demand for low-loss, small-footprint and power-efficient waveguiding solutions in the telecom band. However, most integrated optical circuits suffer from high propagation loss and low integration degree. Through manipulating the valley-dependent topological phase of light, we have experimentally demonstrated both robust optical transport and electrical modulation of lightwaves at telecom wavelengths in the valley photonic crystals. With the adoption of valley kink states, the 25 Gbit/s optical signal at 1550 nm is successfully transmitted through a highly twisted interface. Furthermore, an extreme high data rate of 100 Gbit/s is demonstrated with such topological waveguide by wavelength division multiplexing. The electrical tunability of the topological modulators based on thermo-optic effect is also verified, opening a novel route towards active valley kink photonic devices. Our study shows a great possibility of making use of the topological protection in building up high-speed datalinks on a chip.Published versionThis work was supported by the Innovation and Entrepreneurship Program of Jiangsu Province (JSSCBS20210467), the Natural Science Foundation of the Jiangsu Higher Institution of China (21KJB140012), the Natural Science Foundation of Jiangsu Province (SBK2021041180), the National Natural Science Foundation of China (62105158, 62075038)
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