Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related t...Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related transcription factor Spi1 regulates microglial/macrophage commitment and maturation.However,the effect of Spi1 on intracerebral hemorrhage remains unclear.In this study,we found that Spi1 may regulate recovery from the neuroinflammation and neurofunctional damage caused by intracerebral hemorrhage by modulating the microglial/macrophage transcriptome.We showed that high Spi1expression in microglia/macrophages after intracerebral hemorrhage is associated with the activation of many pathways that promote phagocytosis,glycolysis,and autophagy,as well as debris clearance and sustained remyelination.Notably,microglia with higher levels of Soil expression were chara cterized by activation of pathways associated with a variety of hemorrhage-related cellular processes,such as complement activation,angiogenesis,and coagulation.In conclusion,our results suggest that Spi1 plays a vital role in the microglial/macrophage inflammatory response following intracerebral hemorrhage.This new insight into the regulation of Spi1 and its target genes may advance our understanding of neuroinflammation in intracerebral hemorrhage and provide therapeutic targets for patients with intracerebral hemorrhage.展开更多
Utilizing multi-band and multi-carrier techniques enhances throughput and capacity in Long-Term Evolution(LTE)-Advanced and 5G New Radio(NR)mobile networks.However,these techniques introduce Passive Inter-Modulation(P...Utilizing multi-band and multi-carrier techniques enhances throughput and capacity in Long-Term Evolution(LTE)-Advanced and 5G New Radio(NR)mobile networks.However,these techniques introduce Passive Inter-Modulation(PIM)interference in Frequency-Division Duplexing(FDD)systems.In this paper,a novel multi-band Wiener-Hammerstein model is presented to digitally reconstruct PIM interference signals,thereby achieving effective PIM Cancellation(PIMC)in multi-band scenarios.In the model,transmitted signals are independently processed to simulate Inter-Modulation Distortions(IMDs)and Cross-Modulation Distortions(CMDs).Furthermore,the Finite Impulse Response(FIR)filter,basis function generation,and B-spline function are applied for precise PIM product estimation and generation in multi-band scenarios.Simulations involving 4 carrier components from diverse NR frequency bands at varying transmitting powers validate the feasibility of the model for multi-band PIMC,achieving up to 19 dB in PIMC performance.Compared to other models,this approach offers superior PIMC performance,exceeding them by more than 5 dB in high transmitting power scenarios.Additionally,its lower sampling rate requirement reduces the hardware complexity associated with implementing multi-band PIMC.展开更多
Accumulating evidence has demonstrated the involvement of B cells in neuroinflammation and neuroregeneration.However,the role of B cells in ischemic stroke remains unclear.In this study,we identified a novel phenotype...Accumulating evidence has demonstrated the involvement of B cells in neuroinflammation and neuroregeneration.However,the role of B cells in ischemic stroke remains unclear.In this study,we identified a novel phenotype of macrophage-like B cells in brain-infiltrating immune cells expressing a high level of CD45.Macrophage-like B cells chara cterized by co-expression of B-cell and macrophage markers,showed stronger phagocytic and chemotactic functions compared with other B cells and showed upregulated expression of phagocytosis-related genes.Gene Ontology analysis found that the expression of genes associated with phagocytosis,including phagosome-and lysosome-related genes,was upregulated in macrophage-like B cells.The phagocytic activity of macrophage-like B cells was ve rified by immunostaining and three-dimensional reconstruction,in which TREM2-labeled macrophage-like B cells enwrapped and internalized myelin debris after cerebral ischemia.Cell-cell interaction analysis revealed that macrophage-like B cells released multiple chemokines to recruit peripheral immune cells mainly via CCL pathways.Single-cell RNA sequencing showed that the transdiffe rentiation to macrophage-like B cells may be induced by specific upregulation of the transcription factor CEBP fa mily to the myeloid lineage and/or by downregulation of the transcription factor Pax5 to the lymphoid lineage.Furthermore,this distinct B cell phenotype was detected in brain tissues from mice or patients with traumatic brain injury,Alzheimer’s disease,and glioblastoma.Overall,these results provide a new perspective on the phagocytic capability and chemotactic function of B cells in the ischemic brain.These cells may serve as an immunotherapeutic target for regulating the immune response of ischemic stroke.展开更多
Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide attention.However,GO is easy to aggregate in alkaline cement mortar with poor dispersibility.This hinders its application in practical...Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide attention.However,GO is easy to aggregate in alkaline cement mortar with poor dispersibility.This hinders its application in practical infrastructure construction.In this work,GO-M18 polycarboxylate compound superplasticizer(GM)were obtained by compounding the M18 polycarboxylate superplasticizer with GO solution at different mass ratios.The dispersion of GM in alkaline solution was systematically studied.The phases and functional groups of GM were characterized by XRD and FTIR.The effects of GM on the cement mortar hydration and the formation of microstructure were investigated by measuring the heat of hydration,MIP,TG/DSC,and SEM.The results show that the long-chain structure of the M18 polycarboxylate superplasticizer can increase the interlayer spacing of GO and weaken the force between GO sheets.The modified GO can be uniformly dispersed in the cement slurry.GM can accelerate the early hydration process of cement,which can increase the content of Ca(OH)2 and decrease the grain size.It can optimize the pore size distribution of cement-based materials,increase the density of harmless and less harmful pores,thereby improving mechanical properties.Such methods can transform traditional cement-based materials into stronger,more durable composites,which prolong the life of cement-based materials and reduce the amount of cement used for later maintenance.This provides an idea for achieving sustainability goals in civil engineering.展开更多
In order to know about the influences of disturbance on the operating performance, the present work developed the overall dynamic simulation model of the micro gas turbine and investigated the control system under the...In order to know about the influences of disturbance on the operating performance, the present work developed the overall dynamic simulation model of the micro gas turbine and investigated the control system under the disturbances of environmental temperature and unit load. The response processes of main parameters have been obtained. It found that the compressor pressure ratio and the fuel flow rate increase in the case of natural gas being replaced by pine gas. When the system reaches a new steady state, the main parameters change to different values. The output power decreases with the declining of the air mass flow when the ambient temperature rises, the biomass gas mass flow rate increases under the regulation of the control system to maintain the output power and rotating speed in which the thermal efficiency reduces by 1.40%. The thermal efficiency enhances with the increase of output load. The control system can quickly and effectively act to maintain the key parameters at desired value.展开更多
To reduce greenhouse gases emission and increase the renewable energy uti</span><span style="font-family:Verdana;">lization portion in the world, the biomass gasification coupled with a coal-fire...To reduce greenhouse gases emission and increase the renewable energy uti</span><span style="font-family:Verdana;">lization portion in the world, the biomass gasification coupled with a coal-fired </span><span style="font-family:Verdana;">boiler power generation system is studied. It is a challenge to achieve optimum performance for the coupled system. The models of biomass gasification coupled with co-firing of coal in a boiler have been established. A comparative study of three kinds of biomass (Food Rubbish, Straw and Wood Pellets) has </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">been </span></span></span><span><span><span><span style="font-family:Verdana;">done. The syngas produced in a 10 t/h gasifier is fed to a 330 MWe coal-fired boiler for co-combustion, and the co-firing performances have been compared with pure coal combustion case under the conditions of constant boiler load. Results show that co-firing decreases the furnace combustion temperature and raises the flue gas temperature for Food Rubbish and Straw, while, flue gases temperature decrease in case of Wood Pellets. At the same time NO<sub>x</sub> and SO<sub>x</sub> emissions have reduced. The system efficiencies at constant load for Food Rubbish, Straw and Wood Pellets are 83.25%, </span><span style="font-family:Verdana;">83.88% and 82.56% when the optimum conditions of gasification and co-firing </span><span style="font-family:Verdana;">process are guaranteed.展开更多
Remarkable progress has been made in conjugated copoly-mer donors due to the development of novel fused-ring ac-ceptor(FRA)building units[1−15].The copolymers based on FRA units have delivered excellent power conversi...Remarkable progress has been made in conjugated copoly-mer donors due to the development of novel fused-ring ac-ceptor(FRA)building units[1−15].The copolymers based on FRA units have delivered excellent power conversion efficien-cies(PCEs)up to 18.69%in organic solar cells(OSCs)[16].Fused-ring aromatic lactones are promising FRA units[17−19].展开更多
The fuel staging combustion technology is a promising low NOx combustion technology for coal-fired boiler. In order to reduce NOx emissions, the burners of a 600?MWe coal-fired boiler are retrofitted in which methane ...The fuel staging combustion technology is a promising low NOx combustion technology for coal-fired boiler. In order to reduce NOx emissions, the burners of a 600?MWe coal-fired boiler are retrofitted in which methane gas is selected as a secondary fuel for re-combustion. The CFD models of combustion process are built to investigate?effects of the methane gasratio on combustion process and NOx emissions. A total of 4 cases are numerically studied, including the pure coal combustion case, the coal combustion with 7.5%, 10%, 12.5% of methane gas re-combustion cases respectively. The results show that the re-combustion of methane can reduce the temperature at primary combustion zone, but increase the temperatures at the re-combustion area and the furnace outlet. The NOx concentration at the furnace outlet reduces with the increasing methane gas ratio.?Methane re-combustion can greatly benefit to the NOx emissions reduction.展开更多
The organic cocrystal strategy has provided a convenient and efficient platform for preparing organic photothermal materials.However,the rapidly directional preparation of cocrystals with desirable photothermal proper...The organic cocrystal strategy has provided a convenient and efficient platform for preparing organic photothermal materials.However,the rapidly directional preparation of cocrystals with desirable photothermal properties remains challenging due to a lack of suitable design ideas.Here,two new photothermal cocrystals,MTC and MFC,based on acceptor molecules(TCNQ and F4TCNQ)with different electron-withdrawing capacities were quickly prepared by the coprecipitation method,aiming to explore the effect of charge transfer(CT)interaction on photothermal properties.Compared with MTC,the stronger intermolecular CT interaction in MFC facilitates extending the absorption range(from the NIR-I to the NIR-II region)and enhancing the non-radiative transition process.Under the 808 nm laser irradiation,the photothermal conversion efficiency(PCE)of MFC is 54.6%,whereas MTC displays a mere 36.8%.The MFC cocrystal was further combined with a flexible polymer substrate(HPDMS)to prepare a flexible wearable heater(HPDMS@MFC),which exhibits excellent NIR-II photothermal performance.This work points out a research direction for the rapid assembly of efficient photothermal cocrystals and additionally provides an extensive application prospect for organic photothermal cocrystals in the field of wearable devices.展开更多
Near-infrared organic phototransistors have wide application prospects in many fields.The active materials with the high mobility and near-infrared response are critical to building high-performance near-infrared orga...Near-infrared organic phototransistors have wide application prospects in many fields.The active materials with the high mobility and near-infrared response are critical to building high-performance near-infrared organic phototransistors,which are scarce at present.Herein,a new charge transfer cocrystal using 5,7-dihydroindolo[2,3-b]carbazole(5,7-ICZ)as the donor and 2,2’-(benzo[1,2-b:4,5-b’]dithiophene-4,8-diylidene)dimalononitrile(DTTCNQ)as the acceptor is properly designed and prepared in a stoichiometric ratio(D:A=1:1),which not only displays a high electron mobility of 0.15 cm^(2)V^(-1)s^(-1) and very low dark current,but also can serve as the active layer materials in the region of near-infrared detection due to the narrowed band gap and good charge transport properties.A high photosensitivity of 1.8×10^(4),the ultrahigh photoresponsivity of 2,923 A W-1and the high detectivity of 4.26×10^(11)Jones of the organic near-infrared phototransistors are obtained.展开更多
In this work,a genuinely two-dimensional HLL-type approximate Riemann solver is proposed for hypo-elastic plastic flow.To consider the effects of wave interaction from both the x-and y-directions,a corresponding 2D el...In this work,a genuinely two-dimensional HLL-type approximate Riemann solver is proposed for hypo-elastic plastic flow.To consider the effects of wave interaction from both the x-and y-directions,a corresponding 2D elastic-plastic approximate solver is constructed with elastic-plastic transition embedded.The resultant numerical flux combines one-dimensional numerical flux in the central region of the cell edge and two-dimensional flux in the cell vertex region.The stress is updated separately by using the velocity obtained with the above approximate Riemann solver.Several numerical tests,including genuinely two-dimensional examples,are presented to test the performances of the proposed method.The numerical results demonstrate the credibility of the present 2D approximate Riemann solver.展开更多
Semiconducting two-dimensional conjugated polymers(2DCPs)with strong fluorescence emission have great potential for various optoelectronic applications.However,it is enormously challenging to achieve this goal due to ...Semiconducting two-dimensional conjugated polymers(2DCPs)with strong fluorescence emission have great potential for various optoelectronic applications.However,it is enormously challenging to achieve this goal due to the significant compact interlayerπ-πstacking-induced quenching effect in these systems.In this work,we found that highly fluorescent semiconducting 2DCPs can be prepared through an effective side-chain engineering approach in which interlayer spacers are introduced to reduce the fluorescence quenching effect.The obtained two truxene-based 2DCP films that,along with-C6H13 and-C_(12)H_(25)alkyl side chains as interlayer spacers both demonstrate superior fluorescence properties with a high photoluminescence quantum yield of 5.6%and 14.6%,respectively.These are among the highest values currently reported for 2DCP films.Moreover,an ultralong isotropic quasi-twodimensional exciton diffusion length constrained in the plane with its highest value approaching 110 nm was revealed by the transient photoluminescence microscopy technique,suggesting that theπ-conjugated structure in these truxene-based 2DCP films has effectively been extended.This work can enable a broad exploration of highly fluorescent semiconducting 2DCP films for more deeply fundamental properties and optoelectronic device applications.展开更多
In 1995,Yu et al.[1]first reported bulk-heterojunction(BHJ)solar cells with a conjugated polymer donor and a fullerene acceptor as the active materials.From then on,BHJ organic solar cells(OSCs)have attracted academic...In 1995,Yu et al.[1]first reported bulk-heterojunction(BHJ)solar cells with a conjugated polymer donor and a fullerene acceptor as the active materials.From then on,BHJ organic solar cells(OSCs)have attracted academic and industrial interests due to the advantages like lightweight,flexibility and roll-to-roll fabrication.Nowadays,17%power conversion efficiencies(PCEs)have been achieved in the state-of-the-art OSCs[2,3].The remarkable progress in OSCs relies on the continuously emerging new materials and device fabrication technologies,and the understanding on film morphology and device physics[4,5].展开更多
Since 1995,bulk-heterojunction organic solar cells consisting of one or two organic donors and one or two organic acceptors have been fighting for high power conversion efficiencies(PCEs)and good stability[1].Until re...Since 1995,bulk-heterojunction organic solar cells consisting of one or two organic donors and one or two organic acceptors have been fighting for high power conversion efficiencies(PCEs)and good stability[1].Until recent years,this next-generation photovoltaic technology starts to offer decent PCEs,shedding the light on commercialization,and attracting great attention again[2-14].Compared w让h the continuously emerging highperformance nonfullerene acceptors,high-performance donors are rare.展开更多
Organic light-mitting transistors(OLETs)integrate the functions of light-emitting diodes and field-effect transistors into a unique device,opening a new door for optoelectronics.However,there is still a challenge due ...Organic light-mitting transistors(OLETs)integrate the functions of light-emitting diodes and field-effect transistors into a unique device,opening a new door for optoelectronics.However,there is still a challenge due to the absence of high quality organic semiconductors for OLETs.Herein,we reported a novel molecule 2,6-di(anthracen-2-yl)naphthalene(2,6-DAN),which exhibited mobility of up to 19 cm2:V'-s'and an absolute fluorescence quantum yield of 37.09%,which are good values for organic semiconductors.Moreover,OLETs based on 2,6-DAN single crystals showed bright yellowish-green emission and well-balanced ambipolar charge transport.The excellent ratio of hole to electron mobilty can reach up to 0.86,which is superior to most single component OL ETs in typical device configurations reported so far.展开更多
Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in...Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in solution-processed thin films is crucial for their efficient charge transport and thus high performance optoelectronic devices. Herein, with diketopyrrolopyrrole-quaterthiophene （PDQT） copo/ymer as an example, it is found that by simply reducing the solution concentration for spincoating meanwhile with the assistance of post-annealing, significantly enhanced film crystallinity with formation of typical single crystalline domains is obtained, which benefits from the enough space for better molecular assembly especially at the semiconductor/dielectric interface. High performance polymer transistors and phototransistors were finally constructed based on the optimal lowconcentration （2 mg/mL） spin-coated PDQT films （～12 nm）, which giving a high charge carrier mobility of 2.28 cm2 V-1 s-1 and a photoresponse on/off ratio of 2.1 ×107 at VG = 0 V under white light irradiation of 6mW/cm2. The results suggest that the bright future of PDQT crystalline films for large-area flexible integrated optoelectronic devices and the application of effective low-concentration processing approach in solution-processed organic electronics with reduced material waste.展开更多
Lead halide perovskites have attracted extensive attention in recent years because of their excellent photoelectronic properties, such as high absorption coefficients,carrier mobilities, defect tolerances, and photolu...Lead halide perovskites have attracted extensive attention in recent years because of their excellent photoelectronic properties, such as high absorption coefficients,carrier mobilities, defect tolerances, and photoluminescence efficiencies. However, a key issue hindering their commercial application is the toxicity of lead. Replacing lead with other nontoxic elements is a promising solution to this problem.Considering their atomic radii, relative atomic masses, and electron arrangements, perovskites based on Sn, Bi, Sb, and other elements instead of Pb have been widely synthesized.Here, we summarized the growth methods, photoelectric properties, and device applications of these lead-free perovskites. First, we introduced several common growth methods for lead-free perovskites, including solution methods,solid-state reaction, and chemical vapor deposition methods.Second, we discussed the photoelectric properties and methods for optimizing these properties of lead-free perovskites with different structure dimensions. Finally, the applications of lead-free perovskites in solar cells, light-emitting diodes,and X-ray detectors were examined. This review also provides suggestions for future research on lead-free perovskites.展开更多
基金supported by the National Natural Science Foundation of China,No.81971097(to JY)。
文摘Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related transcription factor Spi1 regulates microglial/macrophage commitment and maturation.However,the effect of Spi1 on intracerebral hemorrhage remains unclear.In this study,we found that Spi1 may regulate recovery from the neuroinflammation and neurofunctional damage caused by intracerebral hemorrhage by modulating the microglial/macrophage transcriptome.We showed that high Spi1expression in microglia/macrophages after intracerebral hemorrhage is associated with the activation of many pathways that promote phagocytosis,glycolysis,and autophagy,as well as debris clearance and sustained remyelination.Notably,microglia with higher levels of Soil expression were chara cterized by activation of pathways associated with a variety of hemorrhage-related cellular processes,such as complement activation,angiogenesis,and coagulation.In conclusion,our results suggest that Spi1 plays a vital role in the microglial/macrophage inflammatory response following intracerebral hemorrhage.This new insight into the regulation of Spi1 and its target genes may advance our understanding of neuroinflammation in intracerebral hemorrhage and provide therapeutic targets for patients with intracerebral hemorrhage.
基金supported by the National Natural Science Foun-dation of China under Grant 11901209,Grant 62374061,and Grant 62271217.
文摘Utilizing multi-band and multi-carrier techniques enhances throughput and capacity in Long-Term Evolution(LTE)-Advanced and 5G New Radio(NR)mobile networks.However,these techniques introduce Passive Inter-Modulation(PIM)interference in Frequency-Division Duplexing(FDD)systems.In this paper,a novel multi-band Wiener-Hammerstein model is presented to digitally reconstruct PIM interference signals,thereby achieving effective PIM Cancellation(PIMC)in multi-band scenarios.In the model,transmitted signals are independently processed to simulate Inter-Modulation Distortions(IMDs)and Cross-Modulation Distortions(CMDs).Furthermore,the Finite Impulse Response(FIR)filter,basis function generation,and B-spline function are applied for precise PIM product estimation and generation in multi-band scenarios.Simulations involving 4 carrier components from diverse NR frequency bands at varying transmitting powers validate the feasibility of the model for multi-band PIMC,achieving up to 19 dB in PIMC performance.Compared to other models,this approach offers superior PIMC performance,exceeding them by more than 5 dB in high transmitting power scenarios.Additionally,its lower sampling rate requirement reduces the hardware complexity associated with implementing multi-band PIMC.
基金National Natural Science Foundation of China,No.82001460the Natural Science Foundation of Zhejiang Province,No.LQ21H250001 (both to LS)。
文摘Accumulating evidence has demonstrated the involvement of B cells in neuroinflammation and neuroregeneration.However,the role of B cells in ischemic stroke remains unclear.In this study,we identified a novel phenotype of macrophage-like B cells in brain-infiltrating immune cells expressing a high level of CD45.Macrophage-like B cells chara cterized by co-expression of B-cell and macrophage markers,showed stronger phagocytic and chemotactic functions compared with other B cells and showed upregulated expression of phagocytosis-related genes.Gene Ontology analysis found that the expression of genes associated with phagocytosis,including phagosome-and lysosome-related genes,was upregulated in macrophage-like B cells.The phagocytic activity of macrophage-like B cells was ve rified by immunostaining and three-dimensional reconstruction,in which TREM2-labeled macrophage-like B cells enwrapped and internalized myelin debris after cerebral ischemia.Cell-cell interaction analysis revealed that macrophage-like B cells released multiple chemokines to recruit peripheral immune cells mainly via CCL pathways.Single-cell RNA sequencing showed that the transdiffe rentiation to macrophage-like B cells may be induced by specific upregulation of the transcription factor CEBP fa mily to the myeloid lineage and/or by downregulation of the transcription factor Pax5 to the lymphoid lineage.Furthermore,this distinct B cell phenotype was detected in brain tissues from mice or patients with traumatic brain injury,Alzheimer’s disease,and glioblastoma.Overall,these results provide a new perspective on the phagocytic capability and chemotactic function of B cells in the ischemic brain.These cells may serve as an immunotherapeutic target for regulating the immune response of ischemic stroke.
基金funded by the National Natural Science Foundation of China(No.51872137)and Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide attention.However,GO is easy to aggregate in alkaline cement mortar with poor dispersibility.This hinders its application in practical infrastructure construction.In this work,GO-M18 polycarboxylate compound superplasticizer(GM)were obtained by compounding the M18 polycarboxylate superplasticizer with GO solution at different mass ratios.The dispersion of GM in alkaline solution was systematically studied.The phases and functional groups of GM were characterized by XRD and FTIR.The effects of GM on the cement mortar hydration and the formation of microstructure were investigated by measuring the heat of hydration,MIP,TG/DSC,and SEM.The results show that the long-chain structure of the M18 polycarboxylate superplasticizer can increase the interlayer spacing of GO and weaken the force between GO sheets.The modified GO can be uniformly dispersed in the cement slurry.GM can accelerate the early hydration process of cement,which can increase the content of Ca(OH)2 and decrease the grain size.It can optimize the pore size distribution of cement-based materials,increase the density of harmless and less harmful pores,thereby improving mechanical properties.Such methods can transform traditional cement-based materials into stronger,more durable composites,which prolong the life of cement-based materials and reduce the amount of cement used for later maintenance.This provides an idea for achieving sustainability goals in civil engineering.
文摘In order to know about the influences of disturbance on the operating performance, the present work developed the overall dynamic simulation model of the micro gas turbine and investigated the control system under the disturbances of environmental temperature and unit load. The response processes of main parameters have been obtained. It found that the compressor pressure ratio and the fuel flow rate increase in the case of natural gas being replaced by pine gas. When the system reaches a new steady state, the main parameters change to different values. The output power decreases with the declining of the air mass flow when the ambient temperature rises, the biomass gas mass flow rate increases under the regulation of the control system to maintain the output power and rotating speed in which the thermal efficiency reduces by 1.40%. The thermal efficiency enhances with the increase of output load. The control system can quickly and effectively act to maintain the key parameters at desired value.
文摘To reduce greenhouse gases emission and increase the renewable energy uti</span><span style="font-family:Verdana;">lization portion in the world, the biomass gasification coupled with a coal-fired </span><span style="font-family:Verdana;">boiler power generation system is studied. It is a challenge to achieve optimum performance for the coupled system. The models of biomass gasification coupled with co-firing of coal in a boiler have been established. A comparative study of three kinds of biomass (Food Rubbish, Straw and Wood Pellets) has </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">been </span></span></span><span><span><span><span style="font-family:Verdana;">done. The syngas produced in a 10 t/h gasifier is fed to a 330 MWe coal-fired boiler for co-combustion, and the co-firing performances have been compared with pure coal combustion case under the conditions of constant boiler load. Results show that co-firing decreases the furnace combustion temperature and raises the flue gas temperature for Food Rubbish and Straw, while, flue gases temperature decrease in case of Wood Pellets. At the same time NO<sub>x</sub> and SO<sub>x</sub> emissions have reduced. The system efficiencies at constant load for Food Rubbish, Straw and Wood Pellets are 83.25%, </span><span style="font-family:Verdana;">83.88% and 82.56% when the optimum conditions of gasification and co-firing </span><span style="font-family:Verdana;">process are guaranteed.
文摘Remarkable progress has been made in conjugated copoly-mer donors due to the development of novel fused-ring ac-ceptor(FRA)building units[1−15].The copolymers based on FRA units have delivered excellent power conversion efficien-cies(PCEs)up to 18.69%in organic solar cells(OSCs)[16].Fused-ring aromatic lactones are promising FRA units[17−19].
文摘The fuel staging combustion technology is a promising low NOx combustion technology for coal-fired boiler. In order to reduce NOx emissions, the burners of a 600?MWe coal-fired boiler are retrofitted in which methane gas is selected as a secondary fuel for re-combustion. The CFD models of combustion process are built to investigate?effects of the methane gasratio on combustion process and NOx emissions. A total of 4 cases are numerically studied, including the pure coal combustion case, the coal combustion with 7.5%, 10%, 12.5% of methane gas re-combustion cases respectively. The results show that the re-combustion of methane can reduce the temperature at primary combustion zone, but increase the temperatures at the re-combustion area and the furnace outlet. The NOx concentration at the furnace outlet reduces with the increasing methane gas ratio.?Methane re-combustion can greatly benefit to the NOx emissions reduction.
基金the National Key R&D Program(2022YFB3603800)the National Natural Science Foundation of China(52121002,U21A6002)+1 种基金Tianjin Natural Science Foundation(20JCJQJC00300)the Fundamental ResearchFunds forthe Central Universities.
文摘The organic cocrystal strategy has provided a convenient and efficient platform for preparing organic photothermal materials.However,the rapidly directional preparation of cocrystals with desirable photothermal properties remains challenging due to a lack of suitable design ideas.Here,two new photothermal cocrystals,MTC and MFC,based on acceptor molecules(TCNQ and F4TCNQ)with different electron-withdrawing capacities were quickly prepared by the coprecipitation method,aiming to explore the effect of charge transfer(CT)interaction on photothermal properties.Compared with MTC,the stronger intermolecular CT interaction in MFC facilitates extending the absorption range(from the NIR-I to the NIR-II region)and enhancing the non-radiative transition process.Under the 808 nm laser irradiation,the photothermal conversion efficiency(PCE)of MFC is 54.6%,whereas MTC displays a mere 36.8%.The MFC cocrystal was further combined with a flexible polymer substrate(HPDMS)to prepare a flexible wearable heater(HPDMS@MFC),which exhibits excellent NIR-II photothermal performance.This work points out a research direction for the rapid assembly of efficient photothermal cocrystals and additionally provides an extensive application prospect for organic photothermal cocrystals in the field of wearable devices.
基金supported by the Ministry of Science and Technology of China(2018YFA0703200 and 2017YFA0204503)the National Natural Science Foundation of China(52121002,51733004,U21A6002,51725304 and 21875158)+1 种基金Tianjin Natural Science Foundation(20JCJQJC00300)China Postdoctoral Science Foundation(2021M692381)。
文摘Near-infrared organic phototransistors have wide application prospects in many fields.The active materials with the high mobility and near-infrared response are critical to building high-performance near-infrared organic phototransistors,which are scarce at present.Herein,a new charge transfer cocrystal using 5,7-dihydroindolo[2,3-b]carbazole(5,7-ICZ)as the donor and 2,2’-(benzo[1,2-b:4,5-b’]dithiophene-4,8-diylidene)dimalononitrile(DTTCNQ)as the acceptor is properly designed and prepared in a stoichiometric ratio(D:A=1:1),which not only displays a high electron mobility of 0.15 cm^(2)V^(-1)s^(-1) and very low dark current,but also can serve as the active layer materials in the region of near-infrared detection due to the narrowed band gap and good charge transport properties.A high photosensitivity of 1.8×10^(4),the ultrahigh photoresponsivity of 2,923 A W-1and the high detectivity of 4.26×10^(11)Jones of the organic near-infrared phototransistors are obtained.
基金supported by the NSFC-NSAF joint fund(Grant No.U1730118)the Science Challenge Project(Grant No.JCKY2016212A502)+1 种基金the National Natural Science Foundation of China(Grant No.12101029)Postdoctoral Science Foundation of China(Grant No.2020M680283).
文摘In this work,a genuinely two-dimensional HLL-type approximate Riemann solver is proposed for hypo-elastic plastic flow.To consider the effects of wave interaction from both the x-and y-directions,a corresponding 2D elastic-plastic approximate solver is constructed with elastic-plastic transition embedded.The resultant numerical flux combines one-dimensional numerical flux in the central region of the cell edge and two-dimensional flux in the cell vertex region.The stress is updated separately by using the velocity obtained with the above approximate Riemann solver.Several numerical tests,including genuinely two-dimensional examples,are presented to test the performances of the proposed method.The numerical results demonstrate the credibility of the present 2D approximate Riemann solver.
基金supported by the Ministry of Science and Technology of China(grant nos.2018YFA0703200 and 2022YFB3603800)the Natural Science Foundation of China(grant nos.21875259,52233010,51725304,61890943,and 22021002)+3 种基金the CAS Project for Young Scientists in Basic Research(grant no.YSBR-053)the Youth Innovation Promotion Association of the Chinese Academy of Sciences,the National Program for Support of Top-notch Young Professionals,the Beijing National Laboratory for Molecular Sciences(grant no.BNLMS-CXXM-202012)the Key Research Program of the Chinese Academy of Sciences(grant no.XDPB13)K.C.Wong Education Foundation(grant no.GJTD-2020-02).
文摘Semiconducting two-dimensional conjugated polymers(2DCPs)with strong fluorescence emission have great potential for various optoelectronic applications.However,it is enormously challenging to achieve this goal due to the significant compact interlayerπ-πstacking-induced quenching effect in these systems.In this work,we found that highly fluorescent semiconducting 2DCPs can be prepared through an effective side-chain engineering approach in which interlayer spacers are introduced to reduce the fluorescence quenching effect.The obtained two truxene-based 2DCP films that,along with-C6H13 and-C_(12)H_(25)alkyl side chains as interlayer spacers both demonstrate superior fluorescence properties with a high photoluminescence quantum yield of 5.6%and 14.6%,respectively.These are among the highest values currently reported for 2DCP films.Moreover,an ultralong isotropic quasi-twodimensional exciton diffusion length constrained in the plane with its highest value approaching 110 nm was revealed by the transient photoluminescence microscopy technique,suggesting that theπ-conjugated structure in these truxene-based 2DCP films has effectively been extended.This work can enable a broad exploration of highly fluorescent semiconducting 2DCP films for more deeply fundamental properties and optoelectronic device applications.
基金the National Key Research and Development Program of China (2017YFA0206600)the National Natural Science Foundation of China (51773045, 21572041, 21772030 and 51922032)the Youth Association for Promoting Innovation (CAS) for financial support.
文摘In 1995,Yu et al.[1]first reported bulk-heterojunction(BHJ)solar cells with a conjugated polymer donor and a fullerene acceptor as the active materials.From then on,BHJ organic solar cells(OSCs)have attracted academic and industrial interests due to the advantages like lightweight,flexibility and roll-to-roll fabrication.Nowadays,17%power conversion efficiencies(PCEs)have been achieved in the state-of-the-art OSCs[2,3].The remarkable progress in OSCs relies on the continuously emerging new materials and device fabrication technologies,and the understanding on film morphology and device physics[4,5].
基金the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21572041,21772030 and 51922032)the Youth Association for Promoting Innovation(CAS)for financial support
文摘Since 1995,bulk-heterojunction organic solar cells consisting of one or two organic donors and one or two organic acceptors have been fighting for high power conversion efficiencies(PCEs)and good stability[1].Until recent years,this next-generation photovoltaic technology starts to offer decent PCEs,shedding the light on commercialization,and attracting great attention again[2-14].Compared w让h the continuously emerging highperformance nonfullerene acceptors,high-performance donors are rare.
基金the National Key R&D Program of China(Nos.2017YFA0204503 and 2016YFB0401100)the National Natural Science Foundation of China(Nos.91833306,21875158,51633006,51703159,51725304,and 51733004).
文摘Organic light-mitting transistors(OLETs)integrate the functions of light-emitting diodes and field-effect transistors into a unique device,opening a new door for optoelectronics.However,there is still a challenge due to the absence of high quality organic semiconductors for OLETs.Herein,we reported a novel molecule 2,6-di(anthracen-2-yl)naphthalene(2,6-DAN),which exhibited mobility of up to 19 cm2:V'-s'and an absolute fluorescence quantum yield of 37.09%,which are good values for organic semiconductors.Moreover,OLETs based on 2,6-DAN single crystals showed bright yellowish-green emission and well-balanced ambipolar charge transport.The excellent ratio of hole to electron mobilty can reach up to 0.86,which is superior to most single component OL ETs in typical device configurations reported so far.
基金financial support from the Ministry of Science and Technology of China (Nos. 2017YFA0204503, 2016YFB0401100)the National Natural Science Foundation of China (Nos. 51725304, 91433115, 51633006, 51733004)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB12030300)National program for support of top-notch young professionals
文摘Conjugated polymers have received considerable attentions over the past years due to their large-area potential applications via low-cost solution processing. Improving crystallinity of conjugated polymer molecules in solution-processed thin films is crucial for their efficient charge transport and thus high performance optoelectronic devices. Herein, with diketopyrrolopyrrole-quaterthiophene （PDQT） copo/ymer as an example, it is found that by simply reducing the solution concentration for spincoating meanwhile with the assistance of post-annealing, significantly enhanced film crystallinity with formation of typical single crystalline domains is obtained, which benefits from the enough space for better molecular assembly especially at the semiconductor/dielectric interface. High performance polymer transistors and phototransistors were finally constructed based on the optimal lowconcentration （2 mg/mL） spin-coated PDQT films （～12 nm）, which giving a high charge carrier mobility of 2.28 cm2 V-1 s-1 and a photoresponse on/off ratio of 2.1 ×107 at VG = 0 V under white light irradiation of 6mW/cm2. The results suggest that the bright future of PDQT crystalline films for large-area flexible integrated optoelectronic devices and the application of effective low-concentration processing approach in solution-processed organic electronics with reduced material waste.
基金Ministry of Science and Technology (2017YFA0205004, 2016YFA0200700)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB36000000)+2 种基金the National Natural Science Foundation of China (61704038, 21673054, 11874130, 12074086, 61307120, 61704038 and 11474187)the Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics (KF201902)the CAS Instrument Development Project (Y950291) for their support。
文摘Lead halide perovskites have attracted extensive attention in recent years because of their excellent photoelectronic properties, such as high absorption coefficients,carrier mobilities, defect tolerances, and photoluminescence efficiencies. However, a key issue hindering their commercial application is the toxicity of lead. Replacing lead with other nontoxic elements is a promising solution to this problem.Considering their atomic radii, relative atomic masses, and electron arrangements, perovskites based on Sn, Bi, Sb, and other elements instead of Pb have been widely synthesized.Here, we summarized the growth methods, photoelectric properties, and device applications of these lead-free perovskites. First, we introduced several common growth methods for lead-free perovskites, including solution methods,solid-state reaction, and chemical vapor deposition methods.Second, we discussed the photoelectric properties and methods for optimizing these properties of lead-free perovskites with different structure dimensions. Finally, the applications of lead-free perovskites in solar cells, light-emitting diodes,and X-ray detectors were examined. This review also provides suggestions for future research on lead-free perovskites.
