A highly sensitive and selective two-photon sensing scheme for detection of cartap was developed by using Au@Ag bimetallic core-shell nanoparticles.Cartap was found to induce the aggregation of Au@Ag nanoparticles and...A highly sensitive and selective two-photon sensing scheme for detection of cartap was developed by using Au@Ag bimetallic core-shell nanoparticles.Cartap was found to induce the aggregation of Au@Ag nanoparticles and up to 700-fold enhancement in two-photon photoluminescence.Huge enhancement in two-photon photoluminescence allows achieving a detection limit of as low as 0.0062 mg/kg,which is better than the conventional colorimetric methods.This two-photon sensing scheme has a broad dynamic range and displays excellent selectivity in detection of cartap against over other ten kinds of commonly used insecticides.展开更多
Bacterial infections associated with biomedical devices and implants have posed a great challenge to global healthcare systems.These infections are mainly caused by bacterial biofilm formed on the surface of biomateri...Bacterial infections associated with biomedical devices and implants have posed a great challenge to global healthcare systems.These infections are mainly caused by bacterial biofilm formed on the surface of biomaterials,protecting the encapsulated bacteria from conventional antibiotic treatment and attack of the immune system.As the bacterial biofilm is difficult to eradicate,bactericidal and antifouling coatings have emerged as promising strategies to prevent biofilm fo rmation and subsequent infections.Hydrogels with three-dimensional crosslinked hydrophilic networks,tunable mechanical property and large drugloading capacity are desirable coating materials,which can kill bacteria and/or prevent bacterial adhesion on the surface,inhibiting biofilm formation.Herein,we review recent developments of hydrogels as anti-infective coatings.Particularly,we highlight two chemical approaches(graft-from and graft-to),which have been used to immobilize hydrogels on surfaces,and present advances in the development of bactericidal(contact-killing and antimicrobial-releasing),antifouling(hydrophilic polymer network)and bifunctional hydrogel coatings with both bactericidal and antifouling activities.In addition,the challe nges of hydrogel coatings for clinical applications are discussed,and future research directions of anti-infective hydrogel coatings are proposed.展开更多
Hybrid RFQ is a spatially periodic structure with RF quadrupoles,which is combined by alternating CH-DTL sections and four-vane RFQ sections.It has higher accelerating efficiency than traditional RFQ,and shows stronge...Hybrid RFQ is a spatially periodic structure with RF quadrupoles,which is combined by alternating CH-DTL sections and four-vane RFQ sections.It has higher accelerating efficiency than traditional RFQ,and shows stronger focusing strength than magnetic focusing DTL,especially when accelerating low r=q ions.An aluminium prototype is developed to explore the practicable structure and research on RF parameters of this accelerating structure.展开更多
The prevalent multi-copy routing algorithms in mobile opportunistic networks(MONs)easily cause network congestion.This paper introduces a disjoint-path(DP)routing algorithm,where each node can only transmit packets on...The prevalent multi-copy routing algorithms in mobile opportunistic networks(MONs)easily cause network congestion.This paper introduces a disjoint-path(DP)routing algorithm,where each node can only transmit packets once except the source node,to effectively control the number of packet copies in the network.The discrete continuous time Markov chain(CTMC)was utilized to analyze the state transition between nodes,and the copy numbers of packets with the DP routing algorithm were calculated.Simulation results indicate that DP has a great improvement in terms of packet delivery ratio,average delivery delay,average network overhead,energy and average hop count.展开更多
基金the Ministry of Education, Singapore (R-143-000-607-112)the National Research Foundation, Prime Minister’s Office, Singapore under its Competitive Research Program (NRF-CRP10-2012-04)Medium Sized Centre Programme
文摘A highly sensitive and selective two-photon sensing scheme for detection of cartap was developed by using Au@Ag bimetallic core-shell nanoparticles.Cartap was found to induce the aggregation of Au@Ag nanoparticles and up to 700-fold enhancement in two-photon photoluminescence.Huge enhancement in two-photon photoluminescence allows achieving a detection limit of as low as 0.0062 mg/kg,which is better than the conventional colorimetric methods.This two-photon sensing scheme has a broad dynamic range and displays excellent selectivity in detection of cartap against over other ten kinds of commonly used insecticides.
基金financially supported by the National Natural Science Foundation of China(Nos.81803481,81830103 and 31900982)the Shenzhen Science and Technology Program(Nos.KQTD20190929173853397 and JCYJ20200109142401698)+1 种基金the Fundamental Research Funds for the Central Universities of China(Nos.20ykpy123 and 19ykpy142)the Institute of Bioengineering and Nanotechnology(Biomedical Research Council,Agency for Science,Technology and Research,Singapore)(Nos.SC 19/08-101002)。
文摘Bacterial infections associated with biomedical devices and implants have posed a great challenge to global healthcare systems.These infections are mainly caused by bacterial biofilm formed on the surface of biomaterials,protecting the encapsulated bacteria from conventional antibiotic treatment and attack of the immune system.As the bacterial biofilm is difficult to eradicate,bactericidal and antifouling coatings have emerged as promising strategies to prevent biofilm fo rmation and subsequent infections.Hydrogels with three-dimensional crosslinked hydrophilic networks,tunable mechanical property and large drugloading capacity are desirable coating materials,which can kill bacteria and/or prevent bacterial adhesion on the surface,inhibiting biofilm formation.Herein,we review recent developments of hydrogels as anti-infective coatings.Particularly,we highlight two chemical approaches(graft-from and graft-to),which have been used to immobilize hydrogels on surfaces,and present advances in the development of bactericidal(contact-killing and antimicrobial-releasing),antifouling(hydrophilic polymer network)and bifunctional hydrogel coatings with both bactericidal and antifouling activities.In addition,the challe nges of hydrogel coatings for clinical applications are discussed,and future research directions of anti-infective hydrogel coatings are proposed.
文摘Hybrid RFQ is a spatially periodic structure with RF quadrupoles,which is combined by alternating CH-DTL sections and four-vane RFQ sections.It has higher accelerating efficiency than traditional RFQ,and shows stronger focusing strength than magnetic focusing DTL,especially when accelerating low r=q ions.An aluminium prototype is developed to explore the practicable structure and research on RF parameters of this accelerating structure.
基金the National Natural Science Foundation of China under Grants U1804164,61902112 and U1404602in part by the Science and Technology Foundation of Henan Educational Committee under Grants 19A510015,20A520019,20A520020.
文摘The prevalent multi-copy routing algorithms in mobile opportunistic networks(MONs)easily cause network congestion.This paper introduces a disjoint-path(DP)routing algorithm,where each node can only transmit packets once except the source node,to effectively control the number of packet copies in the network.The discrete continuous time Markov chain(CTMC)was utilized to analyze the state transition between nodes,and the copy numbers of packets with the DP routing algorithm were calculated.Simulation results indicate that DP has a great improvement in terms of packet delivery ratio,average delivery delay,average network overhead,energy and average hop count.
