The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various field...The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.展开更多
As electromagnetic technology advances and demand for electronic devices grows,concerns about electromagnetic pollution intensify.This has spurred focused research on innovative electromagnetic absorbers,particularly ...As electromagnetic technology advances and demand for electronic devices grows,concerns about electromagnetic pollution intensify.This has spurred focused research on innovative electromagnetic absorbers,particularly chalcogenides,noted for their superior absorption capabilities.In this study,we successfully synthesize 3R–TaS_(2)nanosheets using a straightforward calcination method for the first time.These nanosheets exhibit significant absorption capabilities in both the C-band(4–8 GHz)and Ku-band(12–18 GHz)frequency ranges.By optimizing the calcination process,the complex permittivity of TaS_(2)is enhanced,specifically for those synthesized at 1000℃for 24 h.The nanosheets possess dual-band absorption properties,with a notable minimum reflection loss(RLmin)of41.4 dB in the C-band,and an average absorption intensity exceeding 10 dB in C-and Ku-bands,in the absorbers with a thickness of 5.6 mm.Additionally,the 3R–TaS_(2)nanosheets are demonstrated to have an effective absorption bandwidth of 5.04 GHz(3.84–8.88 GHz)in the absorbers with thicknesses of 3.5–5.5 mm.The results highlight the multiple reflection effects in 3R–TaS_(2)as caused by their stacked structures,which could be promising low-frequency absorbers.展开更多
In order to realize the application of corn stalk in cow feed, we designed experiments to explore the effect of a certain proportion of corn stalk on the performance of lactating dairy cows. 9 multiparous mid-lactatin...In order to realize the application of corn stalk in cow feed, we designed experiments to explore the effect of a certain proportion of corn stalk on the performance of lactating dairy cows. 9 multiparous mid-lactating cows were allocated at random to three groups, each containing 3 intact cows. The trial <span style="font-family:Verdana;">consisted of three periods and three dietary treatments with a 3 × 3 Latin</span> <span style="font-family:Verdana;">square design. The diets were normal concentrats plus dried corn stalk</span><span style="font-family:Verdana;"> chopped to 5 - 8 cm long (N), high concentrates plus dried corn stalks chopped to a length of approximately 5 - 8 cm by a mower (H) while the milled corn stalks were passed through a pulviser with a 2 cm pore size (MH). Each cow was measured for dry matter intake (DMI), ruminal pH, rumen fermentation, se</span><span style="font-family:Verdana;">lective feeding behavior and production performance. The results showed</span><span style="font-family:Verdana;"> that MH led to a significantly higher intake of DM, neutral detergent fiber (NDF), forage NDF (FNDF), acid detergent fiber (ADF), crude protein (CP) and organic matter (OM) than N and H (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> < 0.05). Cows fed H and MH showed similar selective feeding behavior, while those fed H showed various selectiv</span><span style="font-family:Verdana;">ity for the dietary component. MH resulted in a significantly higher milk</span><span style="font-family:Verdana;"> production (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> < 0.05), and tended to have a higher milk fat production than N (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.055). There were no significant differences in the milk components (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.424) and lactose (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.113) between cows fed N and MH. The high-con</span><span style="font-family:Verdana;">centrates plus milled corn stalk diet can increase the milk yield under the</span><span style="font-family:Verdana;"> premise of normal rumen pH in dairy cows, thereby generating higher economic benefits. And milled corn stalk can effectively inhibit the cow’s selective eating of low-quality roughage.</span>展开更多
With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shieldin...With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shielding materials against detrimental electromagnetic radiation plays an essential role.Meanwhile,the EMI shielding materials with high flexibility and functional integrity are highly demanded for emerging shielding applications.Hitherto,a variety of flexible EMI shielding materials with lightweight and multifunctionalities have been developed.In this review,we not only introduce the recent development of flexible EMI shielding materials,but also elaborate the EMI shielding mechanisms and the index for"green EMI shielding"performance.In addition,the construction strategies for sophisticated multifunctionalities of flexible shielding materials are summarized.Finally,we propose several possible research directions for flexible EMI shielding materials in near future,which could be inspirational to the fast-growing next-generation flexible electronic devices with reliable and multipurpose protections as offered by EMI shielding materials.展开更多
Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene o...Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene oxide(WS2-rGO)heterostructure nanosheets were synthesized via a facile hydrothermal process;moreover,their dielectric and MA properties were reported for the first time.Remarkably,the maximum reflection loss(RL)of the sample-wax composites containing 40 wt% WS2-rGO was-41.5 dB at a thickness of 2.7 mm;furthermore,the bandwidth where RL<-10 dB can reach up to 13.62 GHz(4.38-18 GHz).Synergistic mechanisms derived from the interfacial dielectric coupling and multiple-interface scattering after hybridization of WS2 with rGO were discussed to explain the drastically enhanced microwave absorption performance.The results indicate these lightweight WS2-rGO nanosheets to be potential materials for practical electromagnetic wave-absorbing applications.展开更多
The preliminary results of this laboratory (unpublished) indicate that the nutritional value of whole wheat hay (wheat hay, for short) is very high, and the milk stage is the best period of wheat hay harvest. In this ...The preliminary results of this laboratory (unpublished) indicate that the nutritional value of whole wheat hay (wheat hay, for short) is very high, and the milk stage is the best period of wheat hay harvest. In this study, we investigated the feeding effect and economic benefits using wheat hay instead of alfalfa diet for dairy cows under the condition of the same energy and crude protein levels. Three types of diets were used: alfalfa diet, wheat hay diet and alfalfa + wheat hay diet. The results showed that the dry matter digestibility of alfalfa diet and alfalfa + wheat hay diet did not differ significantly (P > 0.1), but was significantly higher than that of wheat hay diet (P < 0.05). The wheat hay diet could produce more propionic acid and ammonia nitrogen (P < 0.05) in the rumen, and reduce the ratio of acetic/propionic and nitrogen utilization. There was no significant difference in milk production among the three diets (P > 0.1). There was no significant difference in milk somatic cell count and body condition score among the three groups (P > 0.1). The wheat hay diet could significantly increase milk protein and lactose (P contents of interleukin-6 in cows fed alfalfa diet and alfalfa + wheat diet were significantly higher than that in cows fed wheat hay diet (P < 0.05). There was no significant difference in interleukinm-6 between in cows fed alfalfa diet and alfalfa + wheat diet (P > 0.05). The use of wheat hay to replace imported alfalfa in whole or in part could save feed costs. Full substitution of alfalfa with wheat hay could have a daily economic benefit of 13.74 yuan.展开更多
Imide-based conjugated molecules have emerged as a highly promising class of building blocks for constructing n-type semiconducting materials with lowlying lowest unoccupied molecular orbitals and exceptional stabilit...Imide-based conjugated molecules have emerged as a highly promising class of building blocks for constructing n-type semiconducting materials with lowlying lowest unoccupied molecular orbitals and exceptional stability.Although imides,such as naphthalene diimides,perylene diimides and their lateral fused analogs,have been synthesized extensively,the design and synthesis of largerπ-extended molecules incorporating more than two imide groups are desirable but still very challenging.Herein,we report the synthesis of an unprecedented electron-deficient bisanthene tetraimide(ATI)containing a bisantheneconjugated core and four five-membered imide groups,which was successfully achieved via a combined approach of solution and on-surface synthesis.The chemical structures,electronic states,formation mechanism and aromaticity of ATI were systematically investigated by scanning tunneling microscopy,noncontact atomic force microscopy,scanning tunneling spectroscopy,and density functional theory calculations.展开更多
Diketopyrrolopyrrole(DPP)and related derivatives have drawn great attention due to their applications in organic optical/electronic materials.Progress in these materials is associated with developments in the synthese...Diketopyrrolopyrrole(DPP)and related derivatives have drawn great attention due to their applications in organic optical/electronic materials.Progress in these materials is associated with developments in the syntheses of the DPP family.Chemical modification of DPP at nitrogen atom,including N-alkylation and N-arylation,is an effective strategy to improve its physical and chemical properties,such as solubility,optical and semiconducting properties.However,N-arylation of DPPs remains challenging compared to the easily accessible N-alkylation.Herein,the synthesis of N-aryl DPP derivatives and correlatedπ-expanded DPPs are summarized,and their optical/electronic properties are introduced.The future perspectives of N-aryl DPP derivatives are also discussed.展开更多
Although VB-Group transition metal disulfides(TMDs)VS_(2)nanomaterials with specific electronic properties and multiphase microstructures have shown fascinating potential in the field of electro-magnetic wave(EMW)abso...Although VB-Group transition metal disulfides(TMDs)VS_(2)nanomaterials with specific electronic properties and multiphase microstructures have shown fascinating potential in the field of electro-magnetic wave(EMW)absorption,the efficient utilization of VS_(2)is limited by the technical bottleneck of its narrow effective absorption bandwidth(EAB)which is attributed to environmental instability and a deficient electromagnetic(EM)loss mechanism.In order to fully exploit the maximal utilization values of VS_(2)nanomaterials for EMW absorption through mitigating the chemical instability and optimizing the EM parameters,biomass-based glucose derived carbon(GDC)like sugar-coating has been decorated on the surface of stacked VS_(2)nanosheets via a facile hydrothermal method,followed by high-temperature carbonization.As a result,the modulation of doping amount of glucose injection solution(Glucose)could effectively manipulate the encapsulation degree of GDC coating on VS_(2)nanosheets,further imple-menting the EM response mechanisms of the VS_(2)/GDC hybrids(coupling effect of conductive loss,interfacial polarization,relaxation,dipole polarization,defect engineering and multiple reflections and absorptions)through regulating the conductivity and constructing multi-interface heterostructures,as reflected by the enhanced EMW absorption performance to a great extent.The minimum reflection loss(Rmin)of VS_(2)/GDC hybrids could reach52.8 dB with a thickness of 2.7 mm at 12.2 GHz.Surprisingly,compared with pristine VS_(2),the EAB of the VS_(2)/GDC hybrids increased from 2.0 to 5.7 GHz,while their environmental stability was effectively enhanced by virtue of GDC doping.Obviously,this work provides a promising candidate to realize frequency band tunability of EMW absorbers with exceptional perfor-mance and environmental stability.展开更多
Isoindigo(IID)is widely used as organic dye and conjugated unit in opto-electronic materials.Functionalization of IID to increase its structural complexity is demanding for obtaining diversity properties.Herein,we dev...Isoindigo(IID)is widely used as organic dye and conjugated unit in opto-electronic materials.Functionalization of IID to increase its structural complexity is demanding for obtaining diversity properties.Herein,we developed a direct C-H/N-H activation method of IIDs via double alkyne annulations and synthesizedπ-extended IIDs with two pairs of 5/7 membered rings.The structure of theπ-extended IIDs was characterized and confirmed by^(1)H NMR,^(13)C NMR,HRMS and X ray crystal analysis.Their physical properties were characterized by UV-vis absorption,cyclic voltammetry and thermogravimetric analysis.The absorption coefficient of the annulated products enhanced significantly compared with the non-annulated analogue.展开更多
The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engin...The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric genes.Electron migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent dipoles.Herein,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent dipoles.By virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 mm.The mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).展开更多
WS2 nanomaterials have attracted great attention in the field of electromagnetic wave absorption due to their high specific surface area,layered structure,and peculiar electronic properties.However,further improvement...WS2 nanomaterials have attracted great attention in the field of electromagnetic wave absorption due to their high specific surface area,layered structure,and peculiar electronic properties.However,further improvements on their limited electromagnetic absorbing(EMA)capacity and bandwidth are urgently required for their practical application as EMA absorbents.In this work,WS2/NiO hybrids with heterostructures are prepared by a hydrothermal method and developed into EMA absorbents.The maximum reflection loss of the hybrids with 20%NiO loading could reach-53.31 dB at a thickness of 4.30 mm;the bandwidth with a reflection loss value of less than-10 dB is determined to be13.46 GHz(4.54–18 GHz)when the thickness of the absorbent is between 3.5 and 5.5 mm.It is found that the enhanced EMA performance of WS2/NiO hybrids is caused by the addition of magnetic NiO,which could result in the interfaces between WS2 and NiO being responsible for the synergetic magnetic loss and dielectric loss in the hybrids.This work provides a new approach for the design of excellent EMA materials for practical applications.展开更多
High performance microwave absorption(MA)materials especially those with tunable frequency are highly desirable for telecommunication industries and military camouflage in the information era.Herein,we constructed hie...High performance microwave absorption(MA)materials especially those with tunable frequency are highly desirable for telecommunication industries and military camouflage in the information era.Herein,we constructed hierarchical heterostructures based on VB-group laminated vanadium disulfide(VS_(2))nanosheets embedded with cobalt tetroxide(Co_(3)O_(4))nanoparticles.The highly dispersed Co_(3)O_(4)nanoparticles generate strong electromagnetic coupling networks that could enhance the loss properties of MA materials.Moreover,the interconnected VS_(2)layered network results in dipolar/interfacial polarization,multiple reflection and scattering favorable for the enhanced MA performance.Impressively,the maximum reflection loss of the VS_(2)/Co_(3)O_(4)hybrids containing 10%Co_(3)O_(4)can reach 57.96 dB at a thin thickness of 1.57 mm,and the bandwidth with an RL value less than-10 dB is as large as 3.5 GHz.The effective MA band could be adjusted in a range of 15.1 GHz(2.9-18 GHz)from S to Ku bands by the increase in thickness from 1.2 mm to 5.5 mm.The results show that the synergistic effect of multiple loss mechanisms and good impedance matching could be the reasons for strong MA capability in nearly all frequency bands,and thus,the high-performance and lightweight MA materials could be developed by the VS_(2)/Co_(3)O_(4)hybrids.展开更多
The construction of structures with multiple interfaces and dielectric/magnetic heterostructures enables the design of materials with unique physical and chemical properties,which has aroused intensive interest in sci...The construction of structures with multiple interfaces and dielectric/magnetic heterostructures enables the design of materials with unique physical and chemical properties,which has aroused intensive interest in scientific and technological fields.Especially,for electromagnetic(EM)wave absorption,enhanced interface polarization and improved impedence match with high Snoek's limitation could be achieved by multiple interfaces and dielectric/magnetic heterostructures,respectively,which are benificial to high-efficiency electromagnetic wave absorption(EWA).However,by far,the principles in the design or construction of structures with multiple interfaces and dielectric/magnetic heterostructures,and the relationships between those structures or heterostructures and their EWA performance have not been fully summarized and reviewed.This article aims to provide a timely review on the research progresses of high-efficency EM wave absorbers with multiple interfaces and dielectric/magnetic heterostructures,focusing on various promising EWA materials.Particularly,EM attenuation mechanisms in those structures with multiple interfaces and dielectric/magnetic heterostructures are discussed and generalized.Furthermore,the changllenges and future developments of EM wave absorbers based on those structures are proposed.展开更多
Summary of main observation and conclusion The development of selenophene-flanked DPP(SeDPP)based copolymers,especially for the ambipolar ones,lags behind other aromatic group flanked DPP-based polymers.Herein,we repo...Summary of main observation and conclusion The development of selenophene-flanked DPP(SeDPP)based copolymers,especially for the ambipolar ones,lags behind other aromatic group flanked DPP-based polymers.Herein,we report two new ambipolar SeDPP-based conjugated polymers.One is the alternating polymer PSeDPPFT with normal SeDPP and 3,4-difluorothiophene units.The other is PSeFDFT,in which the electron acceptor unit is replaced by a new SeDPP derivative,referred as to half-fused SeDPP.The more planar structure of half fused SeDPP endows the backbone of PSeFDFT with good rigidity and planarity.Both polymers exhibit ambipolar transporting properties in air.The PSeFDFT based fleld-effect transistors(FETs)display higher and more balanced ambipolar properties with μnave of 0.27 cm2·V-1·s-1,μe ave of 0.18 cm2·V-1·s-1,and μh ave/μeave of 1.5 than those of PSeDPPFT(μhave=0.11cm2·V-1·s-1,μeave=0.042cm2·V-1·s-1,and μh/μe=2.6).This is attributed to the more planar structure,lower LUMO level,higher HOMO level,and better interchain packing orientations of PSeFDFT by comparing with PSeDPPFT.Therefore,a new molecular design strategy to modulate the hole and electron transporting properties is proposed for conjugated D-A polymers.展开更多
Flexible and wearable electromagnetic interference(EMI)shielding material is one of the current research focuses in the field of EMI shielding.In this work,for the first time,WS_(2)-carbon fiber(WS_(2)-CF)composites a...Flexible and wearable electromagnetic interference(EMI)shielding material is one of the current research focuses in the field of EMI shielding.In this work,for the first time,WS_(2)-carbon fiber(WS_(2)-CF)composites are synthesized by implanting WS_(2),which has a multiphase structure and a large number of defects,onto the surface of carbon fiber(CF)by using a simple one-step hydrothermal method,and are applied to protect electronic devices from EMI.It is found that the EMI shielding performance of WS_(2)-CF is significantly improved,especially for those at Se and C-bands.At 2 GHz,the EMI shielding efficiency could reach 36.0 dB at a typical thickness of 3.00 mm of the composite,which is much better than that of pure CF(25.5 dB).Besides paving a novel avenue to optimize the electromagnetic shielding performance of flexible and wearable CF-based EMI shielding materials,which have great potential in the practical application for EMI shielding,this work provides a new paradigm for the design and synthesis of EMI shielding materials which have a broad application prospect.展开更多
In this paper,we report the design,synthesis and semiconducting behavior of two conjugated D-A polymers BPDDTE and BPDBDTE which entail BPD,a Pechmann dye framework,as electron accepting moieties and(E)-1,2-di(thiophe...In this paper,we report the design,synthesis and semiconducting behavior of two conjugated D-A polymers BPDDTE and BPDBDTE which entail BPD,a Pechmann dye framework,as electron accepting moieties and(E)-1,2-di(thiophen-2-yl)ethane with and without alkyl chains as electron donating moieties.They both show very narrow bandgaps below 1.3 eV.Based on the characterization of the field-effect transistors,thin film of BPDDT exhibits ambipolar semiconducting properties with hole and electron mobilities reaching 0.245 and 0.095 cm^(2)•V^(−1)•s^(−1),respectively,after thermal annealing.Similarly,BPDBDTE with more alkylchains shows ambipolar semiconducting behavior with hole mobility and electron mobilities reaching 0.109 and 0.081 cm^(2)•V^(−1)•s^(−1).Furthermore,BPDBDTE shows good solubilities in several common organic solvents and thus is easily solution-processible.Thus,BPDBDTE is potentially processible with inkjet printing and roll-to-roll printing techniques.展开更多
Imaging-guided photodynamic therapy (PDT) has been regarded as a promising strategy for precise cancer treatment. Because of their excellent modifiability and drug-loading capacity, nanoparticles have played an impo...Imaging-guided photodynamic therapy (PDT) has been regarded as a promising strategy for precise cancer treatment. Because of their excellent modifiability and drug-loading capacity, nanoparticles have played an important role in PDT. Nonetheless, when traditional photosensitizers are made into nanoparticles, both their fluorescence and reactive oxygen species generation efficacy decrease due to a phenomenon known as aggregation-caused quenching. Fortunately, in recent years, several kinds of organic dyes with "abnormal" properties (termed aggregation-induced emission, AIE) were developed. With enhanced fluorescence emission in the nanoaggregation state, the traditional obstacles mentioned above may be overcome by AIE luminogens. Herein, we provide a better combination of photosensitizers and nanoparticles, namely, dual-function AIE nanopartides capable of producing reactive oxygen species, to implement targeted and imaging-guided in vivo PDT. Good contrast of in vivo imaging and obvious therapeutic efficacy were observed at a low dose of AIE nanoparticles and low irradiance of light, thus resulting in negligible side effects. Our work shows that AIE nanopartides may play a promising role in imaging-guided clinical PDT for cancer in the near future.展开更多
Hydrogen sulfide(H_2S)has been found to be the third most important endogenous gaseous signaling molecule after nitric oxide(NO)and carbonic oxide(CO)and plays crucial roles in living organisms and biological systems....Hydrogen sulfide(H_2S)has been found to be the third most important endogenous gaseous signaling molecule after nitric oxide(NO)and carbonic oxide(CO)and plays crucial roles in living organisms and biological systems.Here we use aggregation-induced emission(AIE)of a small organic molecule(TPE-indo)to detect H_2S in both solution and living cells.TPE-indo can target mitochondria and aggregate to fluoresce,which can serve as a sensor for monitoring H_2S in the mitochondria.We regulate the fluorescence of AIE molecules by tuning the viscosity of the solution to form TPE-indo nanoparticles,constructing a probe for H_2S with good selectivity and high sensitivity.The nucleophilic addition of HS-to the TPE-indo is crucial for the rapid H_2S detection.The imaging and analysis of H_2S in mitochondria of living cells with the probe demonstrate potential biological applications.展开更多
The broad class of explosives includes nitro aromatics as well as challenging aliphatic nitro-organics whose detection is important from counter-terrorism and national security perspectives.Here we report a turn-on fl...The broad class of explosives includes nitro aromatics as well as challenging aliphatic nitro-organics whose detection is important from counter-terrorism and national security perspectives.Here we report a turn-on fluorescent sensor array based on aggregation-induced emission(AIE)fluorophores as receptors.To achieve a good sensing system with fast response,good sensitivity and low detection limit,three receptors with abundant chemical diversities for target analytes were synthesized.The turn-on response of the individual receptor showed highly variable and cross-reactive analyte-dependent changes in fluorescence.The excellent ability to identify a variety of explosives,especially the challenging aliphatic nitro-organics(2,3-dimethyl-2,3-dinitrobutane(DMNB),1,3,5-trinitro-1,3,5-triazinane(RDX),cyclotetramethylene tetranitramine(HMX)and entaerythritol tetranitrate(PETN)),was demonstrated in qualitative and quantitative analyses with 100%accuracy.The fluorescence signal amplification in the presence of explosives allows for application of these receptors in a sensor microarray suitable for high-throughput screening.These results suggested that the cross-reactive sensor array based on AIE fluorophores could find a wide range of applications for sensing various analytes or complex mixtures.展开更多
基金This work was supported by the National Natural Science Foundation of China(52372289,52102368,52072192 and 51977009)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905).
文摘The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.
基金supported by the National Natural Science Foundation of China(52372289,52102368,52072192 and 51977009)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020A1515110905)+1 种基金Guangdong Special Fund for key Areas(20237DZX3042)Shenzhen Stable Support Project.
文摘As electromagnetic technology advances and demand for electronic devices grows,concerns about electromagnetic pollution intensify.This has spurred focused research on innovative electromagnetic absorbers,particularly chalcogenides,noted for their superior absorption capabilities.In this study,we successfully synthesize 3R–TaS_(2)nanosheets using a straightforward calcination method for the first time.These nanosheets exhibit significant absorption capabilities in both the C-band(4–8 GHz)and Ku-band(12–18 GHz)frequency ranges.By optimizing the calcination process,the complex permittivity of TaS_(2)is enhanced,specifically for those synthesized at 1000℃for 24 h.The nanosheets possess dual-band absorption properties,with a notable minimum reflection loss(RLmin)of41.4 dB in the C-band,and an average absorption intensity exceeding 10 dB in C-and Ku-bands,in the absorbers with a thickness of 5.6 mm.Additionally,the 3R–TaS_(2)nanosheets are demonstrated to have an effective absorption bandwidth of 5.04 GHz(3.84–8.88 GHz)in the absorbers with thicknesses of 3.5–5.5 mm.The results highlight the multiple reflection effects in 3R–TaS_(2)as caused by their stacked structures,which could be promising low-frequency absorbers.
文摘In order to realize the application of corn stalk in cow feed, we designed experiments to explore the effect of a certain proportion of corn stalk on the performance of lactating dairy cows. 9 multiparous mid-lactating cows were allocated at random to three groups, each containing 3 intact cows. The trial <span style="font-family:Verdana;">consisted of three periods and three dietary treatments with a 3 × 3 Latin</span> <span style="font-family:Verdana;">square design. The diets were normal concentrats plus dried corn stalk</span><span style="font-family:Verdana;"> chopped to 5 - 8 cm long (N), high concentrates plus dried corn stalks chopped to a length of approximately 5 - 8 cm by a mower (H) while the milled corn stalks were passed through a pulviser with a 2 cm pore size (MH). Each cow was measured for dry matter intake (DMI), ruminal pH, rumen fermentation, se</span><span style="font-family:Verdana;">lective feeding behavior and production performance. The results showed</span><span style="font-family:Verdana;"> that MH led to a significantly higher intake of DM, neutral detergent fiber (NDF), forage NDF (FNDF), acid detergent fiber (ADF), crude protein (CP) and organic matter (OM) than N and H (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> < 0.05). Cows fed H and MH showed similar selective feeding behavior, while those fed H showed various selectiv</span><span style="font-family:Verdana;">ity for the dietary component. MH resulted in a significantly higher milk</span><span style="font-family:Verdana;"> production (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> < 0.05), and tended to have a higher milk fat production than N (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.055). There were no significant differences in the milk components (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.424) and lactose (</span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"> = 0.113) between cows fed N and MH. The high-con</span><span style="font-family:Verdana;">centrates plus milled corn stalk diet can increase the milk yield under the</span><span style="font-family:Verdana;"> premise of normal rumen pH in dairy cows, thereby generating higher economic benefits. And milled corn stalk can effectively inhibit the cow’s selective eating of low-quality roughage.</span>
基金This work was financially supported by the National Natural Science Foundation of China(51725101,11727807,51672050,61790581,52102368,52101213)the Ministry of Science and Technology of China(973 Project No.2018YFA0209102)+6 种基金University Development Fund(UDF0100152)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(Grant No.2017ZT07C291)Shenzhen Science and Technology Program(Grant No.KQTD20170810141424366)China Postdoctoral Science Foundation(Grant No.2020M680085)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905)Science and Technology Department of Jiangsu Province of China(Grant No.BK20210261)Open access funding provided by Shanghai Jiao Tong University
文摘With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shielding materials against detrimental electromagnetic radiation plays an essential role.Meanwhile,the EMI shielding materials with high flexibility and functional integrity are highly demanded for emerging shielding applications.Hitherto,a variety of flexible EMI shielding materials with lightweight and multifunctionalities have been developed.In this review,we not only introduce the recent development of flexible EMI shielding materials,but also elaborate the EMI shielding mechanisms and the index for"green EMI shielding"performance.In addition,the construction strategies for sophisticated multifunctionalities of flexible shielding materials are summarized.Finally,we propose several possible research directions for flexible EMI shielding materials in near future,which could be inspirational to the fast-growing next-generation flexible electronic devices with reliable and multipurpose protections as offered by EMI shielding materials.
基金financially supported by the National Natural Science Foundation of China (Nos. 51272110, 51772160, and 51771123)the Shenzhen Peacock Innovation Project (No. KQJSCX20170327151307811)+1 种基金the support of China Scholarship Council (No. 201506100018)the START project of Japan Science and Technology Agency (JST)
文摘Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene oxide(WS2-rGO)heterostructure nanosheets were synthesized via a facile hydrothermal process;moreover,their dielectric and MA properties were reported for the first time.Remarkably,the maximum reflection loss(RL)of the sample-wax composites containing 40 wt% WS2-rGO was-41.5 dB at a thickness of 2.7 mm;furthermore,the bandwidth where RL<-10 dB can reach up to 13.62 GHz(4.38-18 GHz).Synergistic mechanisms derived from the interfacial dielectric coupling and multiple-interface scattering after hybridization of WS2 with rGO were discussed to explain the drastically enhanced microwave absorption performance.The results indicate these lightweight WS2-rGO nanosheets to be potential materials for practical electromagnetic wave-absorbing applications.
文摘The preliminary results of this laboratory (unpublished) indicate that the nutritional value of whole wheat hay (wheat hay, for short) is very high, and the milk stage is the best period of wheat hay harvest. In this study, we investigated the feeding effect and economic benefits using wheat hay instead of alfalfa diet for dairy cows under the condition of the same energy and crude protein levels. Three types of diets were used: alfalfa diet, wheat hay diet and alfalfa + wheat hay diet. The results showed that the dry matter digestibility of alfalfa diet and alfalfa + wheat hay diet did not differ significantly (P > 0.1), but was significantly higher than that of wheat hay diet (P < 0.05). The wheat hay diet could produce more propionic acid and ammonia nitrogen (P < 0.05) in the rumen, and reduce the ratio of acetic/propionic and nitrogen utilization. There was no significant difference in milk production among the three diets (P > 0.1). There was no significant difference in milk somatic cell count and body condition score among the three groups (P > 0.1). The wheat hay diet could significantly increase milk protein and lactose (P contents of interleukin-6 in cows fed alfalfa diet and alfalfa + wheat diet were significantly higher than that in cows fed wheat hay diet (P < 0.05). There was no significant difference in interleukinm-6 between in cows fed alfalfa diet and alfalfa + wheat diet (P > 0.05). The use of wheat hay to replace imported alfalfa in whole or in part could save feed costs. Full substitution of alfalfa with wheat hay could have a daily economic benefit of 13.74 yuan.
基金support from the National Natural Science Foundation of China(grant nos.22161132026,21790053,51821002,and 21602225)the Suzhou Key Laboratory of Surface and Interface Intelligent Matter(grant no.SZS2022011)+2 种基金the Collaborative Innovation Center of Suzhou Nano Science and Technologythe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the 111 project.
文摘Imide-based conjugated molecules have emerged as a highly promising class of building blocks for constructing n-type semiconducting materials with lowlying lowest unoccupied molecular orbitals and exceptional stability.Although imides,such as naphthalene diimides,perylene diimides and their lateral fused analogs,have been synthesized extensively,the design and synthesis of largerπ-extended molecules incorporating more than two imide groups are desirable but still very challenging.Herein,we report the synthesis of an unprecedented electron-deficient bisanthene tetraimide(ATI)containing a bisantheneconjugated core and four five-membered imide groups,which was successfully achieved via a combined approach of solution and on-surface synthesis.The chemical structures,electronic states,formation mechanism and aromaticity of ATI were systematically investigated by scanning tunneling microscopy,noncontact atomic force microscopy,scanning tunneling spectroscopy,and density functional theory calculations.
基金the financial support from National Natural Science Foundation of China(NSFC,Nos.22175081 and 21833005)Beijing National Laboratory for Molecular Sciences(No.BNLM202010)+1 种基金State Key Laboratory of Physical Chemistry of Solid Surfaces(No.202108)Guangdong Provincial Key Laboratory of Catalysis(No.20210701)。
文摘Diketopyrrolopyrrole(DPP)and related derivatives have drawn great attention due to their applications in organic optical/electronic materials.Progress in these materials is associated with developments in the syntheses of the DPP family.Chemical modification of DPP at nitrogen atom,including N-alkylation and N-arylation,is an effective strategy to improve its physical and chemical properties,such as solubility,optical and semiconducting properties.However,N-arylation of DPPs remains challenging compared to the easily accessible N-alkylation.Herein,the synthesis of N-aryl DPP derivatives and correlatedπ-expanded DPPs are summarized,and their optical/electronic properties are introduced.The future perspectives of N-aryl DPP derivatives are also discussed.
基金supported by the National Natural Science Foundation of China(52102368,52072192,51977009)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905).
文摘Although VB-Group transition metal disulfides(TMDs)VS_(2)nanomaterials with specific electronic properties and multiphase microstructures have shown fascinating potential in the field of electro-magnetic wave(EMW)absorption,the efficient utilization of VS_(2)is limited by the technical bottleneck of its narrow effective absorption bandwidth(EAB)which is attributed to environmental instability and a deficient electromagnetic(EM)loss mechanism.In order to fully exploit the maximal utilization values of VS_(2)nanomaterials for EMW absorption through mitigating the chemical instability and optimizing the EM parameters,biomass-based glucose derived carbon(GDC)like sugar-coating has been decorated on the surface of stacked VS_(2)nanosheets via a facile hydrothermal method,followed by high-temperature carbonization.As a result,the modulation of doping amount of glucose injection solution(Glucose)could effectively manipulate the encapsulation degree of GDC coating on VS_(2)nanosheets,further imple-menting the EM response mechanisms of the VS_(2)/GDC hybrids(coupling effect of conductive loss,interfacial polarization,relaxation,dipole polarization,defect engineering and multiple reflections and absorptions)through regulating the conductivity and constructing multi-interface heterostructures,as reflected by the enhanced EMW absorption performance to a great extent.The minimum reflection loss(Rmin)of VS_(2)/GDC hybrids could reach52.8 dB with a thickness of 2.7 mm at 12.2 GHz.Surprisingly,compared with pristine VS_(2),the EAB of the VS_(2)/GDC hybrids increased from 2.0 to 5.7 GHz,while their environmental stability was effectively enhanced by virtue of GDC doping.Obviously,this work provides a promising candidate to realize frequency band tunability of EMW absorbers with exceptional perfor-mance and environmental stability.
基金This work is supported by the NSFC(Nos.22071254,21790363,22021002,22090021,22171245)X.-S.Zhang is grateful for the funding from Youth Innovation Promotion Association CAs(No.2021032)+1 种基金This work is also supported by the Key Research Program of the Chinese Academy of Sciences(Grant No.121111KYSB20200022)the CAS-Croucher Funding Scheme for Joint Laboratories.
文摘Isoindigo(IID)is widely used as organic dye and conjugated unit in opto-electronic materials.Functionalization of IID to increase its structural complexity is demanding for obtaining diversity properties.Herein,we developed a direct C-H/N-H activation method of IIDs via double alkyne annulations and synthesizedπ-extended IIDs with two pairs of 5/7 membered rings.The structure of theπ-extended IIDs was characterized and confirmed by^(1)H NMR,^(13)C NMR,HRMS and X ray crystal analysis.Their physical properties were characterized by UV-vis absorption,cyclic voltammetry and thermogravimetric analysis.The absorption coefficient of the annulated products enhanced significantly compared with the non-annulated analogue.
基金Financial support from the National Natural Science Foundation of China(52372289,52102368,52231007,12327804,T2321003,22088101,22178037 and U22A20424)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020A1515110905)+1 种基金Guangdong Special Fund for key Areas(20237DZX3042)Shenzhen Stable Support Project,Liaoning Revitalization Talents Program(XLYC2002114)are highly appreciated.
文摘The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric genes.Electron migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent dipoles.Herein,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent dipoles.By virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 mm.The mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).
基金supported by the National Natural Science Foundation of China(51272110,51772160,and 51977009).
文摘WS2 nanomaterials have attracted great attention in the field of electromagnetic wave absorption due to their high specific surface area,layered structure,and peculiar electronic properties.However,further improvements on their limited electromagnetic absorbing(EMA)capacity and bandwidth are urgently required for their practical application as EMA absorbents.In this work,WS2/NiO hybrids with heterostructures are prepared by a hydrothermal method and developed into EMA absorbents.The maximum reflection loss of the hybrids with 20%NiO loading could reach-53.31 dB at a thickness of 4.30 mm;the bandwidth with a reflection loss value of less than-10 dB is determined to be13.46 GHz(4.54–18 GHz)when the thickness of the absorbent is between 3.5 and 5.5 mm.It is found that the enhanced EMA performance of WS2/NiO hybrids is caused by the addition of magnetic NiO,which could result in the interfaces between WS2 and NiO being responsible for the synergetic magnetic loss and dielectric loss in the hybrids.This work provides a new approach for the design of excellent EMA materials for practical applications.
基金supported by the National Natural Science Foundation of China(51772160 and 51977009)China Postdoctoral Science Foundation(Grant No.2020M682029)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905)。
文摘High performance microwave absorption(MA)materials especially those with tunable frequency are highly desirable for telecommunication industries and military camouflage in the information era.Herein,we constructed hierarchical heterostructures based on VB-group laminated vanadium disulfide(VS_(2))nanosheets embedded with cobalt tetroxide(Co_(3)O_(4))nanoparticles.The highly dispersed Co_(3)O_(4)nanoparticles generate strong electromagnetic coupling networks that could enhance the loss properties of MA materials.Moreover,the interconnected VS_(2)layered network results in dipolar/interfacial polarization,multiple reflection and scattering favorable for the enhanced MA performance.Impressively,the maximum reflection loss of the VS_(2)/Co_(3)O_(4)hybrids containing 10%Co_(3)O_(4)can reach 57.96 dB at a thin thickness of 1.57 mm,and the bandwidth with an RL value less than-10 dB is as large as 3.5 GHz.The effective MA band could be adjusted in a range of 15.1 GHz(2.9-18 GHz)from S to Ku bands by the increase in thickness from 1.2 mm to 5.5 mm.The results show that the synergistic effect of multiple loss mechanisms and good impedance matching could be the reasons for strong MA capability in nearly all frequency bands,and thus,the high-performance and lightweight MA materials could be developed by the VS_(2)/Co_(3)O_(4)hybrids.
基金The authors are grateful for financial support from the National Key R&D Program of China(2019YFB2204500)the National Natural Science Foundation of China(Grants 51772160,51977009)Postdoctoral Research Foundation of China(2020SA0017).
文摘The construction of structures with multiple interfaces and dielectric/magnetic heterostructures enables the design of materials with unique physical and chemical properties,which has aroused intensive interest in scientific and technological fields.Especially,for electromagnetic(EM)wave absorption,enhanced interface polarization and improved impedence match with high Snoek's limitation could be achieved by multiple interfaces and dielectric/magnetic heterostructures,respectively,which are benificial to high-efficiency electromagnetic wave absorption(EWA).However,by far,the principles in the design or construction of structures with multiple interfaces and dielectric/magnetic heterostructures,and the relationships between those structures or heterostructures and their EWA performance have not been fully summarized and reviewed.This article aims to provide a timely review on the research progresses of high-efficency EM wave absorbers with multiple interfaces and dielectric/magnetic heterostructures,focusing on various promising EWA materials.Particularly,EM attenuation mechanisms in those structures with multiple interfaces and dielectric/magnetic heterostructures are discussed and generalized.Furthermore,the changllenges and future developments of EM wave absorbers based on those structures are proposed.
基金We would like to thank NSFC(61890943,21790360)National Key R&D Program of China(2018YFE0200700,2017YFA0204701)the Youth Innovation Promotion Association CAS(No.2015024)。
文摘Summary of main observation and conclusion The development of selenophene-flanked DPP(SeDPP)based copolymers,especially for the ambipolar ones,lags behind other aromatic group flanked DPP-based polymers.Herein,we report two new ambipolar SeDPP-based conjugated polymers.One is the alternating polymer PSeDPPFT with normal SeDPP and 3,4-difluorothiophene units.The other is PSeFDFT,in which the electron acceptor unit is replaced by a new SeDPP derivative,referred as to half-fused SeDPP.The more planar structure of half fused SeDPP endows the backbone of PSeFDFT with good rigidity and planarity.Both polymers exhibit ambipolar transporting properties in air.The PSeFDFT based fleld-effect transistors(FETs)display higher and more balanced ambipolar properties with μnave of 0.27 cm2·V-1·s-1,μe ave of 0.18 cm2·V-1·s-1,and μh ave/μeave of 1.5 than those of PSeDPPFT(μhave=0.11cm2·V-1·s-1,μeave=0.042cm2·V-1·s-1,and μh/μe=2.6).This is attributed to the more planar structure,lower LUMO level,higher HOMO level,and better interchain packing orientations of PSeFDFT by comparing with PSeDPPFT.Therefore,a new molecular design strategy to modulate the hole and electron transporting properties is proposed for conjugated D-A polymers.
基金This work was supported by the National Natural Science Foundation of China under Grant No.52102368,51772160,51977009.China Postdoctoral Science Foundation(Grant No.2020M682029)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905).
文摘Flexible and wearable electromagnetic interference(EMI)shielding material is one of the current research focuses in the field of EMI shielding.In this work,for the first time,WS_(2)-carbon fiber(WS_(2)-CF)composites are synthesized by implanting WS_(2),which has a multiphase structure and a large number of defects,onto the surface of carbon fiber(CF)by using a simple one-step hydrothermal method,and are applied to protect electronic devices from EMI.It is found that the EMI shielding performance of WS_(2)-CF is significantly improved,especially for those at Se and C-bands.At 2 GHz,the EMI shielding efficiency could reach 36.0 dB at a typical thickness of 3.00 mm of the composite,which is much better than that of pure CF(25.5 dB).Besides paving a novel avenue to optimize the electromagnetic shielding performance of flexible and wearable CF-based EMI shielding materials,which have great potential in the practical application for EMI shielding,this work provides a new paradigm for the design and synthesis of EMI shielding materials which have a broad application prospect.
基金The present research was financially supported by Chinese Academy of Sciences,NSFC(No.21372226)and State Key Basic Research Program.
文摘In this paper,we report the design,synthesis and semiconducting behavior of two conjugated D-A polymers BPDDTE and BPDBDTE which entail BPD,a Pechmann dye framework,as electron accepting moieties and(E)-1,2-di(thiophen-2-yl)ethane with and without alkyl chains as electron donating moieties.They both show very narrow bandgaps below 1.3 eV.Based on the characterization of the field-effect transistors,thin film of BPDDT exhibits ambipolar semiconducting properties with hole and electron mobilities reaching 0.245 and 0.095 cm^(2)•V^(−1)•s^(−1),respectively,after thermal annealing.Similarly,BPDBDTE with more alkylchains shows ambipolar semiconducting behavior with hole mobility and electron mobilities reaching 0.109 and 0.081 cm^(2)•V^(−1)•s^(−1).Furthermore,BPDBDTE shows good solubilities in several common organic solvents and thus is easily solution-processible.Thus,BPDBDTE is potentially processible with inkjet printing and roll-to-roll printing techniques.
基金This work was supported by the National Basic Research Program of China (973 Program) (Nos. 2013CB834704 and 2011CB503700), the National Natural Science Foundation of China (NSFC) (No. 11621101), and the Science and Technology Department of Zhejiang Province (No. 2010R50007)
文摘Imaging-guided photodynamic therapy (PDT) has been regarded as a promising strategy for precise cancer treatment. Because of their excellent modifiability and drug-loading capacity, nanoparticles have played an important role in PDT. Nonetheless, when traditional photosensitizers are made into nanoparticles, both their fluorescence and reactive oxygen species generation efficacy decrease due to a phenomenon known as aggregation-caused quenching. Fortunately, in recent years, several kinds of organic dyes with "abnormal" properties (termed aggregation-induced emission, AIE) were developed. With enhanced fluorescence emission in the nanoaggregation state, the traditional obstacles mentioned above may be overcome by AIE luminogens. Herein, we provide a better combination of photosensitizers and nanoparticles, namely, dual-function AIE nanopartides capable of producing reactive oxygen species, to implement targeted and imaging-guided in vivo PDT. Good contrast of in vivo imaging and obvious therapeutic efficacy were observed at a low dose of AIE nanoparticles and low irradiance of light, thus resulting in negligible side effects. Our work shows that AIE nanopartides may play a promising role in imaging-guided clinical PDT for cancer in the near future.
基金the National Basic Research Program of China(2011CB933201,2012AA022703)the National Natural Science Foundation of China(21222502,91213305)+1 种基金Youth Innovation Promotion Association(CAS),the CAS/SAFEA International Partnership Program for Creative Research Teamsthe“Strategic Priority Research Program”of the Chinese Academy of Sciences(XDA09030305)
文摘Hydrogen sulfide(H_2S)has been found to be the third most important endogenous gaseous signaling molecule after nitric oxide(NO)and carbonic oxide(CO)and plays crucial roles in living organisms and biological systems.Here we use aggregation-induced emission(AIE)of a small organic molecule(TPE-indo)to detect H_2S in both solution and living cells.TPE-indo can target mitochondria and aggregate to fluoresce,which can serve as a sensor for monitoring H_2S in the mitochondria.We regulate the fluorescence of AIE molecules by tuning the viscosity of the solution to form TPE-indo nanoparticles,constructing a probe for H_2S with good selectivity and high sensitivity.The nucleophilic addition of HS-to the TPE-indo is crucial for the rapid H_2S detection.The imaging and analysis of H_2S in mitochondria of living cells with the probe demonstrate potential biological applications.
基金the National Natural Science Foundation of China(50873051,205333050)National High Technology Research and Development Program of China(2007AA03Z307)Transregional Project(TRR61)
文摘The broad class of explosives includes nitro aromatics as well as challenging aliphatic nitro-organics whose detection is important from counter-terrorism and national security perspectives.Here we report a turn-on fluorescent sensor array based on aggregation-induced emission(AIE)fluorophores as receptors.To achieve a good sensing system with fast response,good sensitivity and low detection limit,three receptors with abundant chemical diversities for target analytes were synthesized.The turn-on response of the individual receptor showed highly variable and cross-reactive analyte-dependent changes in fluorescence.The excellent ability to identify a variety of explosives,especially the challenging aliphatic nitro-organics(2,3-dimethyl-2,3-dinitrobutane(DMNB),1,3,5-trinitro-1,3,5-triazinane(RDX),cyclotetramethylene tetranitramine(HMX)and entaerythritol tetranitrate(PETN)),was demonstrated in qualitative and quantitative analyses with 100%accuracy.The fluorescence signal amplification in the presence of explosives allows for application of these receptors in a sensor microarray suitable for high-throughput screening.These results suggested that the cross-reactive sensor array based on AIE fluorophores could find a wide range of applications for sensing various analytes or complex mixtures.