Cellular senescence assumes pivotal roles in various diseases through the secretion of proinflammatory factors.Despite extensive investigations into vascular senescence associated with aging and degenerative diseases,...Cellular senescence assumes pivotal roles in various diseases through the secretion of proinflammatory factors.Despite extensive investigations into vascular senescence associated with aging and degenerative diseases,the molecular mechanisms governing microvascular endothelial cell senescence induced by traumatic stress,particularly its involvement in senescence-induced inflammation,remain insufficiently elucidated.In this study,we present a comprehensive demonstration and characterization of microvascular endothelial cell senescence induced by spinal cord injury(SCI).Lysine demethylase 6A(Kdm6a),commonly known as UTX,emerges as a crucial regulator of cell senescence in injured spinal cord microvascular endothelial cells(SCMECs).Upregulation of UTX induces senescence in SCMECs,leading to an amplified release of proinflammatory factors,specifically the senescenceassociated secretory phenotype(SASP)components,thereby modulating the inflammatory microenvironment.Conversely,the deletion of UTX in endothelial cells shields SCMECs against senescence,mitigates the release of proinflammatory SASP factors,and promotes neurological functional recovery after SCI.UTX forms an epigenetic regulatory axis by binding to calponin 1(CNN1),orchestrating trauma-induced SCMECs senescence and SASP secretion,thereby influencing neuroinflammation and neurological functional repair.Furthermore,local delivery of a senolytic drug reduces senescent SCMECs and suppresses proinflammatory SASP secretion,reinstating a local regenerative microenvironment and enhancing functional repair after SCI.In conclusion,targeting the UTX-CNN1 epigenetic axis to prevent trauma-induced SCMECs senescence holds the potential to inhibit SASP secretion,alleviate neuroinflammation,and provide a novel treatment strategy for SCI repair.展开更多
Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-met...Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.展开更多
Trehalose(TRE)was used to improve the gastrointestinal tolerance of Lactobacillus plantarum embedded with whey protein concentrate/pullulan(WPC/PUL)hydrogel and the embedded L.plantarum was applied to juice.The study ...Trehalose(TRE)was used to improve the gastrointestinal tolerance of Lactobacillus plantarum embedded with whey protein concentrate/pullulan(WPC/PUL)hydrogel and the embedded L.plantarum was applied to juice.The study indicated that 5%TRE significantly increased the viable counts of L.plantarum embedded in WPC/PUL hydrogel from(8.83±0.03)to(9.14±0.04)(lg(CFU/g))in simulated gastric juice(SGJ)and from(9.13±0.04)to(9.38±0.04)(lg(CFU/g))in simulated intestinal juice,respectively.The addition of TRE improved the glass transition temperature of WPC/PUL hydrogel and decreased the hardness and its solubility in SGJ,which may be responsible for the improved protection of WPC/PUL hydrogels on L.plantarum.In addition,TRE increased the viable counts of L.plantarum in WPC/PUL probiotic microcapsule juice at low pH and high temperature during storage.展开更多
Background:Although it has been established that the human Solute Carrier Family 22(SLC22)functions as a cationic transporter,influencing cellular biological metabolism by modulating the uptake of various cations,its ...Background:Although it has been established that the human Solute Carrier Family 22(SLC22)functions as a cationic transporter,influencing cellular biological metabolism by modulating the uptake of various cations,its impact on cancer prognosis remains unclear.Methods:We conducted a comprehensive analysis utilizing data from The Cancer Genome Atlas(TCGA)and other databases to assess the prognostic value and functional implications across various tumors.Silence of SLC22A1 RNA in glioma U251 cells was performed to access the impact of SLC22A1 on lowergrade glioma(LGG)progression.Results:Our findings demonstrated a significant correlation between SLC22A1 expression and the survival time of patients with various cancers(p<0.05).Importantly,we found the potential involvement of SLC22A1 in occurrence and progress of certain cancers,with a pronounced impact on LGG.Further examination of the SLC22A1-LGG relationship revealed its status as an independent risk factor for LGG,suggesting its potential involvement in regulating diverse immune pathways and metabolic activities.Chinese Glioma Genome Atlas(CGGA)data supported the reliability of the risk score as a prognostic and recurrence indicator,emphasizing the accuracy of the nomograph(1,3,and 5-year-AUC>0.8).Cell proliferation and clone formation experiment proved that decreased expression of SLC22A1 in glioma U251 cells inhibited glioma cell growth.Conclusion:Our findings suggest SLC22A1 has huge prospects as a promising biomarker and therapeutic target for LGG prognosis.SLC22A1 has only been proved to support cellular function previously.Our findings demonstrated a robust connection between the tumor microenvironment and functional proteins that maintain basal cell metabolism,which gifts unique tumor immune characteristics of gliomas.Additionally,we provide a highly practical prediction model for estimating the survival rate of LGG patients.展开更多
The lymphatic vasculature forms an organized network that covers the whole body and is involved in fluid homeostasis,metabolite clearance,and immune surveillance.The recent identification of functional lymphatic vesse...The lymphatic vasculature forms an organized network that covers the whole body and is involved in fluid homeostasis,metabolite clearance,and immune surveillance.The recent identification of functional lymphatic vessels in the meninges of the brain and the spinal cord has provided novel insights into neurophysiology.They emerge as major pathways for fluid exchange.The abundance of immune cells in lymphatic vessels and meninges also suggests that lymphatic vessels are actively involved in neuroimmunity.The lymphatic system,through its role in the clearance of neurotoxic proteins,autoimmune cell infiltration,and the transmission of pro-inflammatory signals,participates in the pathogenesis of a variety of neurological disorders,including neurodegenerative and neuroinflammatory diseases and traumatic injury.Vascular endothelial growth factor C is the master regulator of lymphangiogenesis,a process that is critical for the maintenance of central nervous system homeostasis.In this review,we summarize current knowledge and recent advances relating to the anatomical features and immunological functions of the lymphatic system of the central nervous system and highlight its potential as a therapeutic target for neurological disorders and central nervous system repair.展开更多
Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of a...Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.展开更多
It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series...It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series of terpolymers featuring with an antioxidant butylated hydroxytoluene(BHT)-terminated side chain,PTzBI-EHp-BTBHTx and N2200-BTBHTx(x=0.05,0.1,0.2),are designed and synthesized.It was found that incorporating appropriate ratio of benzothiadiazole(BT)with BHT side chains on the conjugated backbone would induce negligible effect on the molecular weight,absorption spectra and energy levels of polymers,however,which would obviously enhance the photostability of these polymers.Consequently,all-polymer solar cells(all-PSCs)and photodetectors were fabricated,and the all-PSC based on PTzBI-EHp-BTBHT0.05:N2200 realized an optimal power conversion efficiency(PCE)approaching~10%,outperforming the device based on pristine PTzBI-EHp:N2200.Impressively,the all-PSCs based on BHT-featuring terpolymers displayed alleviated PCEs degradation under continuous irradiation for 300 h due to the improved morphological and photostability of active layers.The OPDs based on BHT-featuring terpolymers achieved a lower dark current at−0.1 bias,which could be stabilized even after irradiation over 400 h.This study provides a feasible approach to develop terpolymers with antioxidant efficacy for improving the lifetime of OSCs and OPDs.展开更多
The stability of organic solar cells(OSCs)remains a major concern for their ultimate industrialization due to the photo,oxygen,and water susceptibility of organic photoactive materials.Usually,antioxidant additives ar...The stability of organic solar cells(OSCs)remains a major concern for their ultimate industrialization due to the photo,oxygen,and water susceptibility of organic photoactive materials.Usually,antioxidant additives are blended as radical scavengers into the active layer.However,it will induce the intrinsic morphology instability and adversely affect the efficiency and long-term stability.Herein,the antioxidant dibutylhydroxytoluene(BHT)group has been covalently linked onto the side chain of benzothiadiazole(BT)unit,and a series of ternary copolymers D18-Cl-BTBHTx(x=0,0.05,0.1,0.2)with varied ratio of BHT-containing side chains have been synthesized.It was found that the introduction of BHT side chains would have a negligible effect on the photophysical properties and electronic levels,and the D18-Cl-BTBHT0.05:Y6-based OSC achieved the highest power conversion efficiency(PCE)of 17.6%,which is higher than those based active layer blended with BHT additives.More importantly,the unencapsulated device based on D18-Cl-BTBHTx(x=0.05,0.1,0.2)retained approximately 50%of the initial PCE over 30 hours operation under ambient conditions,significantly outperforming the control device based on D18-Cl(90%degradation in PCE after 30 h).This work provides a new structural design strategy of copolymers for OSCs with simultaneously improved efficiency and stability.展开更多
A 2D-3V implicit immersed-finite-element particle-in-cell(IFE-PIC)model is introduced to investigate the radio-frequency(RF)self-bias accelerating system applied in the RF ion thruster.A set of holes in a two-grid sys...A 2D-3V implicit immersed-finite-element particle-in-cell(IFE-PIC)model is introduced to investigate the radio-frequency(RF)self-bias accelerating system applied in the RF ion thruster.A set of holes in a two-grid system with slit apertures is simulated in Cartesian coordinates.The characteristics of the plasma plume,such as the ion density,the neutralization rate and the ion and electron current density were investigated for different RF voltage amplitudes(600-1200V)and frequencies(6-30 MHz).Furthermore,the performance of the thruster was also carefully studied.The simulation results show that a well-focused plasma beam can be formed when the voltage amplitude is larger than 900 V and the frequency exceeds the reciprocal of ion transit time(≥12 MHz)in our simulation cases.The performance of the system can be evidently improved by increasing the voltage amplitude and the frequency,and the losses of the particle and thrust are reduced correspondingly.The bulk region of the plasma beam downstream shows good quasi-neutrality,and the ions are dominant in the peripheral region when a well-focused state is achieved.The high ion density beamlet in the periphery of the ion beam is closer to the axis when the voltage amplitude is increasing,while it is expanded radially when increasing the frequency.Backstream electrons have been observed upstream,and this mainly occurs in the phase in which the electron cannot escape.展开更多
An experimental study on the quasi-neutral beam extracted by a neutralizer-free gridded ion thruster prototype was presented.The prototype was designed using an inductively coupled plasma source terminated by a double...An experimental study on the quasi-neutral beam extracted by a neutralizer-free gridded ion thruster prototype was presented.The prototype was designed using an inductively coupled plasma source terminated by a double-grid accelerator.The beam characteristics were compared when the accelerator was radio-frequency(RF)biased and direct-current(DC)biased.An RF power supply was applied to the screen grid via a blocking capacitor for the RF acceleration,and a DC power supply was directly connected to the screen grid for the DC acceleration.Argon was used as the propellant gas.Furthermore,the characteristics of the plasma beam,such as the floating potential,the spatial distribution of ion flux,and the ion energy distribution function(IEDF)were measured by a four-grid retarding field energy analyzer.The floating potential results showed that the beam space charge is compensated in the case of RF acceleration without a neutralizer,which is similar to the case of classical DC acceleration with a neutralizer.The ion flux of RF acceleration is 1.17 times higher than that of DC acceleration under the same DC component voltage between the double-grid.Moreover,there are significant differences in the beam IEDFs for RF and DC acceleration.The IEDF of RF acceleration has a widened and multipeaked profile,and the main peak moves toward the high-energy region with increasing the DC self-bias voltage.In addition,by comparing the IEDFs with RF acceleration frequencies of3.9 and 7.8 MHz,it is found that the IEDF has a more centered main peak and a narrower energy spread at a higher frequency.展开更多
Degenerative disc disease(DDD) is associated with intervertebral disc degeneration of spinal instability. Here, we report that the cilia of nucleus pulposus(NP) cells mediate mechanotransduction to maintain anabolic a...Degenerative disc disease(DDD) is associated with intervertebral disc degeneration of spinal instability. Here, we report that the cilia of nucleus pulposus(NP) cells mediate mechanotransduction to maintain anabolic activity in the discs. We found that mechanical stress promotes transport of parathyroid hormone 1 receptor(PTH1 R) to the cilia and enhances parathyroid hormone(PTH) signaling in NP cells. PTH induces transcription of integrin α_vβ_6 to activate the transforming growth factor(TGF)-β-connective tissue growth factor(CCN2)-matrix proteins signaling cascade. Intermittent injection of PTH(iPTH) effectively attenuates disc degeneration of aged mice by direct signaling through NP cells, specifically improving intervertebral disc height and volume by increasing levels of TGF-β activity, CCN2, and aggrecan. PTH1 R is expressed in both mouse and human NP cells. Importantly,knockout PTH1 R or cilia in the NP cells results in significant disc degeneration and blunts the effect of PTH on attenuation of aged discs. Thus, mechanical stress-induced transport of PTH1 R to the cilia enhances PTH signaling, which helps maintain intervertebral disc homeostasis, particularly during aging, indicating therapeutic potential of iPTH for DDD.展开更多
AIM: To investigate the antitumor and synergistic effect of Chinese medicine “Bushen huayu jiedu recipe” (recipe for invigorating the kidney, removing blood stasis and toxic substances) and chemotherapy on mice h...AIM: To investigate the antitumor and synergistic effect of Chinese medicine “Bushen huayu jiedu recipe” (recipe for invigorating the kidney, removing blood stasis and toxic substances) and chemotherapy on mice hepatocarcinoma. METHODS: Bushen huayu jiedu recipe (BSHYJDR) consisting of Chinese Cassia Bark, Psoralea, Zedoary, Rhubarb, etc. is equal to 1.5 g/mL liquid of originated herbs after being decoded, filtered, and concentrated. Kunming mice, weighing 18-22 g, were injected with 0.2 mL ascitic hepatocarcinoma H22 containing 1 × 10^7 cells/mL into armpit of the right forelimb of mice. After 24 h, the mice were weighed and randomly divided into tumor-bearing model control group, cisplatin (DDP) group, BSHYJDR high dosage group, low dosage BSHYJDR group, DDP combined with high and low dosage BSHYJDR group, 10 mice in each group. DDP group received injection intraperitoneally (ip) at the dosage of 1 mg/kg (equal to 1/10 LD50), once a day for 4 d. High and low dosage BSHYJDR groups received intragastric BSHYJDR at the dosages of 26.6 and 13.3 g/kg (20 and 10 times each of clinical adult dosage) respectively, while tumor-bearing model group received the equal volume of distilled water once a day for 10 d. On the 11^th d, the mice were weighed and killed, then the tumor was dissected and weighed, the repression rate (RR) was calculated according to the mean weight of tumor (MWT). RESULTS: Compared to the model group (MWT: 1.30±0.73), DDP group (MWT: 0.41±0.09, RR: 68.46%) had a significant difference in the inhibition of hepatocarcinoma H22 (P〈0.01). High dosage BSHYJDR group (MWT: 0.69±0.29, RR: 46.92%) also had a significant difference in inhibition (P〈0.05), while no difference was found in low dosage BSHYJDR group (MVVT: 0.85±0.34, RR: 34.62%) (P〉0.05). When DDP was combined with high dosage BSHYJDR (MWT: 0.29±0.17, RR: 77.69%) and low dosage BSHYJDR (MWT: 0.38±0.21, RR: 70.77%) respectively, we could see improvement of the inhibition effect of DDP on transplanted hepatocarcinoma H22. DDP combined with high dosage BSHYJDR had a significant difference (P〈0.001) compared to DDP, while DDP combined with low dosage BSHYJDR only had a little improvement that is not remarkable. CONCLUSION: Chinese medicine BSHYJDR in combination with chemotherapy can inhibit transplanted hepatocarcinorna in mice.展开更多
Biobutanol is attracting increasingly interest as a source of renewable energy and biofuels because of its many advantages over bioethanol that include higher energy density, fuel efficiency, and reduced engine damage...Biobutanol is attracting increasingly interest as a source of renewable energy and biofuels because of its many advantages over bioethanol that include higher energy density, fuel efficiency, and reduced engine damages. Currently, there is a growing interest in producing biobutanol from bioethanol, in view of the tremendous potential benefits of this transformation for the bulk production of biobutanol in a target specific manner. This perspective paper describes recent progress for the ethanol to butanol process. The different catalysts, including homogeneous and heterogeneous catalytic systems, for ethanol to butanol are outlined and compared, and the key issues and requirements for future developments are highlighted. A major challenge for further development and application of ethanol to butanol process is to find an optimal balance between different catalytic functions and to suppress the formation of side products that has plagued most catalytic bioethanol upgrading systems. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B. V. and Science Press. All rights reserved.展开更多
Molecular design of either polymer donors or acceptors is a promising strategy to tune the morphology of the active layer of organic solar cells,enabling a high-performance device.Thereinto,developing novel polymer do...Molecular design of either polymer donors or acceptors is a promising strategy to tune the morphology of the active layer of organic solar cells,enabling a high-performance device.Thereinto,developing novel polymer donors is an alternative method to obtain high photovoltaic performance.Herein,we present a facile side-chain engineering on the dithiophenobenzotriazole(DTBTz)unit of newly-designed polymer donors(named p BDT-DTBTz-EH and p BDT-DTBTz-Me)to boost the performance of non-fullerene solar cells.Compared with p BDT-DTBTz-EH with long N-alkyl side chains,p BDT-DTBTz-Me with a short methyl exhibits stronger molecular aggregation,higher absorption coefficient,and preferred face-on orientation packing.As a consequence,p BDT-DTBTz-Me based devices achieve an optimal power conversion efficiency of 15.31%when donors are paired with the narrow bandgap acceptor Y6,which is superior to that of p BDT-DTBTz-EH based devices(9.17%).Additionally,the p BDT-DTBTz-Me based devices manifest more effective charge separation and transfer than p BDT-DTBTz-EH based devices.These results indicate that fine-tuning side chains of polymer donors provide new insights for the design of high-performance polymer donors in non-fullerene solar cells.展开更多
As one of the core parts of two-terminal(2 T) monolithic tandem photovoltaics, the interconnecting layers(ICLs) play a critical role in modulating the carrier transport and recombination between the sub-cells,and thus...As one of the core parts of two-terminal(2 T) monolithic tandem photovoltaics, the interconnecting layers(ICLs) play a critical role in modulating the carrier transport and recombination between the sub-cells,and thus influencing the tandem device performance. Here, for the first time, the relationship between ICLs architecture and 2 T monolithic perovskite/organic tandem device performance has been studied by investigating the change of ICLs composition layer thickness on the ICLs optical and electrical properties, sub-cells EQE properties, and tandem device J-V properties. It is revealed that the ability of ICLs on modulating the sub-cells carrier balance properties is strongly associated with its composited layers thickness, and the tandem device carrier balance properties can be reflected by the relative EQE intensity between the sub-cells. Finally, with a deep understanding of the mechanisms, rational design of ICLs can be made to benefit the tandem device development. Based on the optimized ICL a high PCE of 20.03% is achieved.展开更多
Non-fullerene polymer solar cells(NF-PSCs) have gained wide attention recently. Molecular design of non-fullerene electron acceptors effectively promotes the photovoltaic performance of NF-PSCs. However,molecular elec...Non-fullerene polymer solar cells(NF-PSCs) have gained wide attention recently. Molecular design of non-fullerene electron acceptors effectively promotes the photovoltaic performance of NF-PSCs. However,molecular electron acceptors with 2-dimensional(2 D) configuration and conjugation are seldom reported.Herein, we designed and synthesized a series of novel 2 D electron acceptors for efficient NF-PSCs. With rational optimization on the conjugated moieties in both vertical and horizontal direction, these 2 D electron acceptors showed appealing properties, such as good planarity, full-spectrum absorption, high absorption extinction coefficient, and proper blend morphology with donor polymer. A high PCE of 9.76%was achieved for photovoltaic devices with PBDB-T as the donor and these 2 D electron acceptors. It was also found the charge transfer between the conjugated moieties in two directions of these 2 D molecules contributes to the utilization of absorbed photos, resulting in an exceptional EQE of 87% at 730 nm. This work presents rational design guidelines of 2 D electron acceptors, which showed great promise to achieve high-performance non-fullerene polymer solar cells.展开更多
The intersection point of the characteristic magnetic field line(CMFL) crossing the anode boundary with the discharge channel wall, and its influence on thruster performance and the energy and flux of ions bombardin...The intersection point of the characteristic magnetic field line(CMFL) crossing the anode boundary with the discharge channel wall, and its influence on thruster performance and the energy and flux of ions bombarding the channel wall, have been studied numerically. The simulation results demonstrate that with the increase in distance from the crossover point of the CMFL with the channel wall to the bottom of the thruster channel, the ionization rate in the discharge channel gradually increases; meanwhile, the ion energy and ion current density bombarding the channel wall decreases. When the point of the CMFL with the channel wall is at the channel outlet, the thrust, specific impulse, and efficiency are at a maximum, while the ion energy and ion current density bombarding the channel wall are at a minimum. Therefore, to improve the performance and lifetime of the thruster, it is important to control the point of intersection of the CMFL with the channel wall.展开更多
Deoxygenative upgrading of 5-hydromethylfurfural(HMF)into valuable chemicals has attracted intensive research interest in recent years,with product selectivity control remaining an important topic.Herein,TiO_(2) suppo...Deoxygenative upgrading of 5-hydromethylfurfural(HMF)into valuable chemicals has attracted intensive research interest in recent years,with product selectivity control remaining an important topic.Herein,TiO_(2) supported gold catalysts coated with a thin N-doped porous carbon(NPC)layer were developed via a polydopamine-coating-carbonization strategy and utilized for pathway-specific conversion of HMF into 5-methylfurfural(5-MF)with the use of renewable formic acid(FA)as the deoxygenation reagent.The as-fabricated Au/TiO_(2)@NPC exhibited excellent catalytic performance with a high yield of 5-MF(>95%).The catalytic behavior of Au@NPC-based catalysts was shown to be correlated with the suitable combination of highly dispersed Au nanoparticles and favorable interfacial interactions in the Au@NPC core-shell hetero-nanoarchitectures,thereby facilitating the preferential esterification of HMF with FA and suppressing unproductive FA dehydrogenation,which promoted the selective formylation/decarboxylation of hydroxy-methyl group in HMF in a pathway-specific manner.The present NPC/metal interfacial engineering strategy may provide a potential guide for the rational design of advanced catalysts for a wide variety of heterogeneous catalysis processes in terms of the conversion of biomass source.展开更多
We describe herein that the quasi-one-dimensional confinement effect of functionalized nanoporous supports is particularly advantageous for boosting formic acid(FA)dehydrogenation efficiency over palladium nanoparticl...We describe herein that the quasi-one-dimensional confinement effect of functionalized nanoporous supports is particularly advantageous for boosting formic acid(FA)dehydrogenation efficiency over palladium nanoparticles(NPs).Benefiting from their unique structural merits that lead to significant lowering of the entropic barrier for FA activation,the Pd NPs interiorly located on the amino-modified MCM-41 offer the promise of more than an order of magnitude speedup of the initial activity in H2 production from FA over their exterior analogs.Under mild and additive-free conditions,ultrafine Pd NPs confined in aminomodified MCM-41 channels exhibit an initial turnover frequency as high as 46,677 h-1 and a turnover number up to 1,060,000 at 60℃.In conjunction with the enhancement and robust performance for efficient regeneration of FA via CO2 hydrogenation,the presented approach greatly contributes to the development of FA-based hydrogen storage and related technologies as viable means of enabling sustainable future energy prospects.展开更多
Oceanic vertical mixing of the lower halocline water(LHW)in the Chukchi Borderland and Mendeleyev Ridge was studied based on in situ hydrographic and turbulent observations.The depth-averaged turbulent dissipation rat...Oceanic vertical mixing of the lower halocline water(LHW)in the Chukchi Borderland and Mendeleyev Ridge was studied based on in situ hydrographic and turbulent observations.The depth-averaged turbulent dissipation rate of LHW demonstrates a clear topographic dependence,with a mean value of 1.2×10^(-9) W/kg in the southwest of Canada Basin,1.5×10^(-9) W/kg in the Mendeleyev Abyssal Plain,2.4×10^(-9) W/kg on the Mendeleyev Ridge,and2.7×10^(-9) W/kg on the Chukchi Cap.Correspondingly,the mean depth-averaged vertical heat flux of the LHW is0.21 W/m^(2) in the southwest Canada Basin,0.30 W/m^(2) in the Mendeleyev Abyssal Plain,0.39 W/m^(2) on the Mendeleyev Ridge,and 0.46 W/m^(2) on the Chukchi Cap.However,in the presence of Pacific Winter Water,the upward heat released from Atlantic Water through the lower halocline can hardly contribute to the surface ocean.Further,the underlying mechanisms of diapycnal mixing in LHW—double diffusion and shear instability—was investigated.The mixing in LHW where double diffusion were observed is always relatively weaker,with corresponding dissipation rate ranging from 1.01×10^(-9) W/kg to 1.57×10^(-9) W/kg.The results also show a strong correlation between the depth-average dissipation rate and strain variance in the LHW,which indicates a close physical linkage between the turbulent mixing and internal wave activities.In addition,both surface wind forcing and semidiurnal tides significantly contribute to the turbulent mixing in the LHW.展开更多
基金funded by National Natural Science Foundation of China(grant 82030071 and 82272495)Natural Science Foundation of Hunan Province(grant 2020JJ5930 and 2020JJ4874)the Science and Technology Major Project of Changsha(No.kh2103008).
文摘Cellular senescence assumes pivotal roles in various diseases through the secretion of proinflammatory factors.Despite extensive investigations into vascular senescence associated with aging and degenerative diseases,the molecular mechanisms governing microvascular endothelial cell senescence induced by traumatic stress,particularly its involvement in senescence-induced inflammation,remain insufficiently elucidated.In this study,we present a comprehensive demonstration and characterization of microvascular endothelial cell senescence induced by spinal cord injury(SCI).Lysine demethylase 6A(Kdm6a),commonly known as UTX,emerges as a crucial regulator of cell senescence in injured spinal cord microvascular endothelial cells(SCMECs).Upregulation of UTX induces senescence in SCMECs,leading to an amplified release of proinflammatory factors,specifically the senescenceassociated secretory phenotype(SASP)components,thereby modulating the inflammatory microenvironment.Conversely,the deletion of UTX in endothelial cells shields SCMECs against senescence,mitigates the release of proinflammatory SASP factors,and promotes neurological functional recovery after SCI.UTX forms an epigenetic regulatory axis by binding to calponin 1(CNN1),orchestrating trauma-induced SCMECs senescence and SASP secretion,thereby influencing neuroinflammation and neurological functional repair.Furthermore,local delivery of a senolytic drug reduces senescent SCMECs and suppresses proinflammatory SASP secretion,reinstating a local regenerative microenvironment and enhancing functional repair after SCI.In conclusion,targeting the UTX-CNN1 epigenetic axis to prevent trauma-induced SCMECs senescence holds the potential to inhibit SASP secretion,alleviate neuroinflammation,and provide a novel treatment strategy for SCI repair.
基金supported by the National Natural Science Foundation of China,Nos.82030071 (to JH),82272495 (to YC)Science and Technology Major Project of Changsha,No.kh2103008 (to JH)Graduate Students’ Independent Innovative Projects of Hunan Province,No.CX20230311 (to YJ)。
文摘Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.
基金Financial support was provided by the Jilin Provincial Science and Technology Department(20220202086NC)Jilin Provincial Science and Technology Development Plan Project(20220508115RC).
文摘Trehalose(TRE)was used to improve the gastrointestinal tolerance of Lactobacillus plantarum embedded with whey protein concentrate/pullulan(WPC/PUL)hydrogel and the embedded L.plantarum was applied to juice.The study indicated that 5%TRE significantly increased the viable counts of L.plantarum embedded in WPC/PUL hydrogel from(8.83±0.03)to(9.14±0.04)(lg(CFU/g))in simulated gastric juice(SGJ)and from(9.13±0.04)to(9.38±0.04)(lg(CFU/g))in simulated intestinal juice,respectively.The addition of TRE improved the glass transition temperature of WPC/PUL hydrogel and decreased the hardness and its solubility in SGJ,which may be responsible for the improved protection of WPC/PUL hydrogels on L.plantarum.In addition,TRE increased the viable counts of L.plantarum in WPC/PUL probiotic microcapsule juice at low pH and high temperature during storage.
基金supported by National Natural Science Foundation of China(82160639)the Guizhou Provincial Science&Technology Program(QKHJC[2021]571)+2 种基金the Science&Technology Plan of Zunyi(ZSKHHZ[2020]87)the Xin Miao Foundation of Zunyi Medical University(QKPTRC[2019]-026)the PhD Start-Up Foundation of Zunyi Medical University(F-948).
文摘Background:Although it has been established that the human Solute Carrier Family 22(SLC22)functions as a cationic transporter,influencing cellular biological metabolism by modulating the uptake of various cations,its impact on cancer prognosis remains unclear.Methods:We conducted a comprehensive analysis utilizing data from The Cancer Genome Atlas(TCGA)and other databases to assess the prognostic value and functional implications across various tumors.Silence of SLC22A1 RNA in glioma U251 cells was performed to access the impact of SLC22A1 on lowergrade glioma(LGG)progression.Results:Our findings demonstrated a significant correlation between SLC22A1 expression and the survival time of patients with various cancers(p<0.05).Importantly,we found the potential involvement of SLC22A1 in occurrence and progress of certain cancers,with a pronounced impact on LGG.Further examination of the SLC22A1-LGG relationship revealed its status as an independent risk factor for LGG,suggesting its potential involvement in regulating diverse immune pathways and metabolic activities.Chinese Glioma Genome Atlas(CGGA)data supported the reliability of the risk score as a prognostic and recurrence indicator,emphasizing the accuracy of the nomograph(1,3,and 5-year-AUC>0.8).Cell proliferation and clone formation experiment proved that decreased expression of SLC22A1 in glioma U251 cells inhibited glioma cell growth.Conclusion:Our findings suggest SLC22A1 has huge prospects as a promising biomarker and therapeutic target for LGG prognosis.SLC22A1 has only been proved to support cellular function previously.Our findings demonstrated a robust connection between the tumor microenvironment and functional proteins that maintain basal cell metabolism,which gifts unique tumor immune characteristics of gliomas.Additionally,we provide a highly practical prediction model for estimating the survival rate of LGG patients.
基金supported by the Key Program of the National Natural Science Foundation of ChinaNo.82030071+1 种基金the Science and Technology Major Project of ChangshaNo.kh2103008 (both to JZH)
文摘The lymphatic vasculature forms an organized network that covers the whole body and is involved in fluid homeostasis,metabolite clearance,and immune surveillance.The recent identification of functional lymphatic vessels in the meninges of the brain and the spinal cord has provided novel insights into neurophysiology.They emerge as major pathways for fluid exchange.The abundance of immune cells in lymphatic vessels and meninges also suggests that lymphatic vessels are actively involved in neuroimmunity.The lymphatic system,through its role in the clearance of neurotoxic proteins,autoimmune cell infiltration,and the transmission of pro-inflammatory signals,participates in the pathogenesis of a variety of neurological disorders,including neurodegenerative and neuroinflammatory diseases and traumatic injury.Vascular endothelial growth factor C is the master regulator of lymphangiogenesis,a process that is critical for the maintenance of central nervous system homeostasis.In this review,we summarize current knowledge and recent advances relating to the anatomical features and immunological functions of the lymphatic system of the central nervous system and highlight its potential as a therapeutic target for neurological disorders and central nervous system repair.
基金supported by the Natural Nature Science Foundation of China,Nos.82030071,81874004the Science and Technology Major Project of Changsha,No.kh2103008(all to JZH).
文摘Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.
基金The work was financially supported by National Key Research and Development Program of China(2019YFA0705900,2022YFB4200400)funded by MOSTthe Basic and Applied Basic Research Major Program of Guangdong Province(No.2019B030302007)+2 种基金the National Natural Science Foundation of China(No.U21A6002)Guangdong-Hong Kong-Macao joint laboratory of optoelectronic and magnetic functional materials(No.2019B121205002)C.Z.acknowledges the financial support by Basic and Applied Basic Research Major Program of Guangdong Province(No.202201010270).
文摘It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series of terpolymers featuring with an antioxidant butylated hydroxytoluene(BHT)-terminated side chain,PTzBI-EHp-BTBHTx and N2200-BTBHTx(x=0.05,0.1,0.2),are designed and synthesized.It was found that incorporating appropriate ratio of benzothiadiazole(BT)with BHT side chains on the conjugated backbone would induce negligible effect on the molecular weight,absorption spectra and energy levels of polymers,however,which would obviously enhance the photostability of these polymers.Consequently,all-polymer solar cells(all-PSCs)and photodetectors were fabricated,and the all-PSC based on PTzBI-EHp-BTBHT0.05:N2200 realized an optimal power conversion efficiency(PCE)approaching~10%,outperforming the device based on pristine PTzBI-EHp:N2200.Impressively,the all-PSCs based on BHT-featuring terpolymers displayed alleviated PCEs degradation under continuous irradiation for 300 h due to the improved morphological and photostability of active layers.The OPDs based on BHT-featuring terpolymers achieved a lower dark current at−0.1 bias,which could be stabilized even after irradiation over 400 h.This study provides a feasible approach to develop terpolymers with antioxidant efficacy for improving the lifetime of OSCs and OPDs.
基金This work was financially supported by National Key Research and Development Program of China(No.2019YFA0705900)funded by MOSTthe Basic and Applied Basic Research Major Program of Guangdong Province(No.2019B030302007)+1 种基金the National Natural Science Foundation of China(No.U21A6002)Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials(No.2019B121205002).
文摘The stability of organic solar cells(OSCs)remains a major concern for their ultimate industrialization due to the photo,oxygen,and water susceptibility of organic photoactive materials.Usually,antioxidant additives are blended as radical scavengers into the active layer.However,it will induce the intrinsic morphology instability and adversely affect the efficiency and long-term stability.Herein,the antioxidant dibutylhydroxytoluene(BHT)group has been covalently linked onto the side chain of benzothiadiazole(BT)unit,and a series of ternary copolymers D18-Cl-BTBHTx(x=0,0.05,0.1,0.2)with varied ratio of BHT-containing side chains have been synthesized.It was found that the introduction of BHT side chains would have a negligible effect on the photophysical properties and electronic levels,and the D18-Cl-BTBHT0.05:Y6-based OSC achieved the highest power conversion efficiency(PCE)of 17.6%,which is higher than those based active layer blended with BHT additives.More importantly,the unencapsulated device based on D18-Cl-BTBHTx(x=0.05,0.1,0.2)retained approximately 50%of the initial PCE over 30 hours operation under ambient conditions,significantly outperforming the control device based on D18-Cl(90%degradation in PCE after 30 h).This work provides a new structural design strategy of copolymers for OSCs with simultaneously improved efficiency and stability.
基金supported by the China Postdoctoral Science Foundation(No.2022M710977)National Natural Science Foundation of China(No.51907039)+1 种基金the Natural Science Foundation of Guangdong Province(Nos.2022A1515110215 and 2023A1515010137)Shenzhen Technology Projects(Nos.JCYJ20190806142603534 and ZDSYS201707280904031)。
文摘A 2D-3V implicit immersed-finite-element particle-in-cell(IFE-PIC)model is introduced to investigate the radio-frequency(RF)self-bias accelerating system applied in the RF ion thruster.A set of holes in a two-grid system with slit apertures is simulated in Cartesian coordinates.The characteristics of the plasma plume,such as the ion density,the neutralization rate and the ion and electron current density were investigated for different RF voltage amplitudes(600-1200V)and frequencies(6-30 MHz).Furthermore,the performance of the thruster was also carefully studied.The simulation results show that a well-focused plasma beam can be formed when the voltage amplitude is larger than 900 V and the frequency exceeds the reciprocal of ion transit time(≥12 MHz)in our simulation cases.The performance of the system can be evidently improved by increasing the voltage amplitude and the frequency,and the losses of the particle and thrust are reduced correspondingly.The bulk region of the plasma beam downstream shows good quasi-neutrality,and the ions are dominant in the peripheral region when a well-focused state is achieved.The high ion density beamlet in the periphery of the ion beam is closer to the axis when the voltage amplitude is increasing,while it is expanded radially when increasing the frequency.Backstream electrons have been observed upstream,and this mainly occurs in the phase in which the electron cannot escape.
基金supported by Shenzhen Technology Projects(No.ZDSYS201707280904031)the China Postdoctoral Science Foundation(No.2022M710977)。
文摘An experimental study on the quasi-neutral beam extracted by a neutralizer-free gridded ion thruster prototype was presented.The prototype was designed using an inductively coupled plasma source terminated by a double-grid accelerator.The beam characteristics were compared when the accelerator was radio-frequency(RF)biased and direct-current(DC)biased.An RF power supply was applied to the screen grid via a blocking capacitor for the RF acceleration,and a DC power supply was directly connected to the screen grid for the DC acceleration.Argon was used as the propellant gas.Furthermore,the characteristics of the plasma beam,such as the floating potential,the spatial distribution of ion flux,and the ion energy distribution function(IEDF)were measured by a four-grid retarding field energy analyzer.The floating potential results showed that the beam space charge is compensated in the case of RF acceleration without a neutralizer,which is similar to the case of classical DC acceleration with a neutralizer.The ion flux of RF acceleration is 1.17 times higher than that of DC acceleration under the same DC component voltage between the double-grid.Moreover,there are significant differences in the beam IEDFs for RF and DC acceleration.The IEDF of RF acceleration has a widened and multipeaked profile,and the main peak moves toward the high-energy region with increasing the DC self-bias voltage.In addition,by comparing the IEDFs with RF acceleration frequencies of3.9 and 7.8 MHz,it is found that the IEDF has a more centered main peak and a narrower energy spread at a higher frequency.
基金supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health under Award Numbers AR071432 and AR063943
文摘Degenerative disc disease(DDD) is associated with intervertebral disc degeneration of spinal instability. Here, we report that the cilia of nucleus pulposus(NP) cells mediate mechanotransduction to maintain anabolic activity in the discs. We found that mechanical stress promotes transport of parathyroid hormone 1 receptor(PTH1 R) to the cilia and enhances parathyroid hormone(PTH) signaling in NP cells. PTH induces transcription of integrin α_vβ_6 to activate the transforming growth factor(TGF)-β-connective tissue growth factor(CCN2)-matrix proteins signaling cascade. Intermittent injection of PTH(iPTH) effectively attenuates disc degeneration of aged mice by direct signaling through NP cells, specifically improving intervertebral disc height and volume by increasing levels of TGF-β activity, CCN2, and aggrecan. PTH1 R is expressed in both mouse and human NP cells. Importantly,knockout PTH1 R or cilia in the NP cells results in significant disc degeneration and blunts the effect of PTH on attenuation of aged discs. Thus, mechanical stress-induced transport of PTH1 R to the cilia enhances PTH signaling, which helps maintain intervertebral disc homeostasis, particularly during aging, indicating therapeutic potential of iPTH for DDD.
基金Supported by the Postdoctoral Science Foundation of China, No. [2001] 5
文摘AIM: To investigate the antitumor and synergistic effect of Chinese medicine “Bushen huayu jiedu recipe” (recipe for invigorating the kidney, removing blood stasis and toxic substances) and chemotherapy on mice hepatocarcinoma. METHODS: Bushen huayu jiedu recipe (BSHYJDR) consisting of Chinese Cassia Bark, Psoralea, Zedoary, Rhubarb, etc. is equal to 1.5 g/mL liquid of originated herbs after being decoded, filtered, and concentrated. Kunming mice, weighing 18-22 g, were injected with 0.2 mL ascitic hepatocarcinoma H22 containing 1 × 10^7 cells/mL into armpit of the right forelimb of mice. After 24 h, the mice were weighed and randomly divided into tumor-bearing model control group, cisplatin (DDP) group, BSHYJDR high dosage group, low dosage BSHYJDR group, DDP combined with high and low dosage BSHYJDR group, 10 mice in each group. DDP group received injection intraperitoneally (ip) at the dosage of 1 mg/kg (equal to 1/10 LD50), once a day for 4 d. High and low dosage BSHYJDR groups received intragastric BSHYJDR at the dosages of 26.6 and 13.3 g/kg (20 and 10 times each of clinical adult dosage) respectively, while tumor-bearing model group received the equal volume of distilled water once a day for 10 d. On the 11^th d, the mice were weighed and killed, then the tumor was dissected and weighed, the repression rate (RR) was calculated according to the mean weight of tumor (MWT). RESULTS: Compared to the model group (MWT: 1.30±0.73), DDP group (MWT: 0.41±0.09, RR: 68.46%) had a significant difference in the inhibition of hepatocarcinoma H22 (P〈0.01). High dosage BSHYJDR group (MWT: 0.69±0.29, RR: 46.92%) also had a significant difference in inhibition (P〈0.05), while no difference was found in low dosage BSHYJDR group (MVVT: 0.85±0.34, RR: 34.62%) (P〉0.05). When DDP was combined with high dosage BSHYJDR (MWT: 0.29±0.17, RR: 77.69%) and low dosage BSHYJDR (MWT: 0.38±0.21, RR: 70.77%) respectively, we could see improvement of the inhibition effect of DDP on transplanted hepatocarcinoma H22. DDP combined with high dosage BSHYJDR had a significant difference (P〈0.001) compared to DDP, while DDP combined with low dosage BSHYJDR only had a little improvement that is not remarkable. CONCLUSION: Chinese medicine BSHYJDR in combination with chemotherapy can inhibit transplanted hepatocarcinorna in mice.
基金supported by the National Natural Science Foundation of China(21273044,21473035,and 91545108)SINOPEC(X514005)the Open project of State Key Laboratory of Chemical Engineering(SKL-Ch E-15C02)
文摘Biobutanol is attracting increasingly interest as a source of renewable energy and biofuels because of its many advantages over bioethanol that include higher energy density, fuel efficiency, and reduced engine damages. Currently, there is a growing interest in producing biobutanol from bioethanol, in view of the tremendous potential benefits of this transformation for the bulk production of biobutanol in a target specific manner. This perspective paper describes recent progress for the ethanol to butanol process. The different catalysts, including homogeneous and heterogeneous catalytic systems, for ethanol to butanol are outlined and compared, and the key issues and requirements for future developments are highlighted. A major challenge for further development and application of ethanol to butanol process is to find an optimal balance between different catalytic functions and to suppress the formation of side products that has plagued most catalytic bioethanol upgrading systems. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B. V. and Science Press. All rights reserved.
基金financially supported by the National Key Research and Development Program of China(Grant No.2019YFA0705900)funded by MOST and the Basic and Applied Basic Research Major Program of Guangdong Province(Grant No.2019B030302007)。
文摘Molecular design of either polymer donors or acceptors is a promising strategy to tune the morphology of the active layer of organic solar cells,enabling a high-performance device.Thereinto,developing novel polymer donors is an alternative method to obtain high photovoltaic performance.Herein,we present a facile side-chain engineering on the dithiophenobenzotriazole(DTBTz)unit of newly-designed polymer donors(named p BDT-DTBTz-EH and p BDT-DTBTz-Me)to boost the performance of non-fullerene solar cells.Compared with p BDT-DTBTz-EH with long N-alkyl side chains,p BDT-DTBTz-Me with a short methyl exhibits stronger molecular aggregation,higher absorption coefficient,and preferred face-on orientation packing.As a consequence,p BDT-DTBTz-Me based devices achieve an optimal power conversion efficiency of 15.31%when donors are paired with the narrow bandgap acceptor Y6,which is superior to that of p BDT-DTBTz-EH based devices(9.17%).Additionally,the p BDT-DTBTz-Me based devices manifest more effective charge separation and transfer than p BDT-DTBTz-EH based devices.These results indicate that fine-tuning side chains of polymer donors provide new insights for the design of high-performance polymer donors in non-fullerene solar cells.
基金financially supported by the Guangdong Major Project of Basic and Applied Basic Research(2019B030302007)the Ministry of Science and Technology(2017YFA0206600,2019YFA0705900)+6 种基金the Natural Science Foundation of China(51973063,91733302 and 51803060)Guangdong Basic and Applied Basic Research Foundation for Distinguished Young Scholar(2021B1515020028)the Fund of Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates(South China University of Technology)(2019B030301003)the Science and Technology Program of Guangzhou,China(201904010147)the funding by State Key Lab of Luminescent Materials and Devices,South China University of Technologythe Fellowship of China Postdoctoral Science Foundation(2020M682703)the National Natural Science Foundation of China(52003090)。
文摘As one of the core parts of two-terminal(2 T) monolithic tandem photovoltaics, the interconnecting layers(ICLs) play a critical role in modulating the carrier transport and recombination between the sub-cells,and thus influencing the tandem device performance. Here, for the first time, the relationship between ICLs architecture and 2 T monolithic perovskite/organic tandem device performance has been studied by investigating the change of ICLs composition layer thickness on the ICLs optical and electrical properties, sub-cells EQE properties, and tandem device J-V properties. It is revealed that the ability of ICLs on modulating the sub-cells carrier balance properties is strongly associated with its composited layers thickness, and the tandem device carrier balance properties can be reflected by the relative EQE intensity between the sub-cells. Finally, with a deep understanding of the mechanisms, rational design of ICLs can be made to benefit the tandem device development. Based on the optimized ICL a high PCE of 20.03% is achieved.
基金financially supported by the National Key Research and Development Program of China (No. 2019YFA0705900) funded by MOSTthe Basic and Applied Basic Research Major Program of Guangdong Province (No. 2019B030302007)the National Natural Science Foundation of China (No. 51521002)。
文摘Non-fullerene polymer solar cells(NF-PSCs) have gained wide attention recently. Molecular design of non-fullerene electron acceptors effectively promotes the photovoltaic performance of NF-PSCs. However,molecular electron acceptors with 2-dimensional(2 D) configuration and conjugation are seldom reported.Herein, we designed and synthesized a series of novel 2 D electron acceptors for efficient NF-PSCs. With rational optimization on the conjugated moieties in both vertical and horizontal direction, these 2 D electron acceptors showed appealing properties, such as good planarity, full-spectrum absorption, high absorption extinction coefficient, and proper blend morphology with donor polymer. A high PCE of 9.76%was achieved for photovoltaic devices with PBDB-T as the donor and these 2 D electron acceptors. It was also found the charge transfer between the conjugated moieties in two directions of these 2 D molecules contributes to the utilization of absorbed photos, resulting in an exceptional EQE of 87% at 730 nm. This work presents rational design guidelines of 2 D electron acceptors, which showed great promise to achieve high-performance non-fullerene polymer solar cells.
基金financially supported by National Natural Science Foundation of China(Grant Nos.51777045 and51477035)Shenzhen Technology Project(Project Nos.JCYJ20160226201347750 and JCYJ20150529115038093)
文摘The intersection point of the characteristic magnetic field line(CMFL) crossing the anode boundary with the discharge channel wall, and its influence on thruster performance and the energy and flux of ions bombarding the channel wall, have been studied numerically. The simulation results demonstrate that with the increase in distance from the crossover point of the CMFL with the channel wall to the bottom of the thruster channel, the ionization rate in the discharge channel gradually increases; meanwhile, the ion energy and ion current density bombarding the channel wall decreases. When the point of the CMFL with the channel wall is at the channel outlet, the thrust, specific impulse, and efficiency are at a maximum, while the ion energy and ion current density bombarding the channel wall are at a minimum. Therefore, to improve the performance and lifetime of the thruster, it is important to control the point of intersection of the CMFL with the channel wall.
文摘Deoxygenative upgrading of 5-hydromethylfurfural(HMF)into valuable chemicals has attracted intensive research interest in recent years,with product selectivity control remaining an important topic.Herein,TiO_(2) supported gold catalysts coated with a thin N-doped porous carbon(NPC)layer were developed via a polydopamine-coating-carbonization strategy and utilized for pathway-specific conversion of HMF into 5-methylfurfural(5-MF)with the use of renewable formic acid(FA)as the deoxygenation reagent.The as-fabricated Au/TiO_(2)@NPC exhibited excellent catalytic performance with a high yield of 5-MF(>95%).The catalytic behavior of Au@NPC-based catalysts was shown to be correlated with the suitable combination of highly dispersed Au nanoparticles and favorable interfacial interactions in the Au@NPC core-shell hetero-nanoarchitectures,thereby facilitating the preferential esterification of HMF with FA and suppressing unproductive FA dehydrogenation,which promoted the selective formylation/decarboxylation of hydroxy-methyl group in HMF in a pathway-specific manner.The present NPC/metal interfacial engineering strategy may provide a potential guide for the rational design of advanced catalysts for a wide variety of heterogeneous catalysis processes in terms of the conversion of biomass source.
基金Financial support from NSF of China(21773033,21972024,91645201)Science&Technology Commission of Shanghai Municipality(19DZ2270100)SINOPEC(X514005)is acknowledged。
文摘We describe herein that the quasi-one-dimensional confinement effect of functionalized nanoporous supports is particularly advantageous for boosting formic acid(FA)dehydrogenation efficiency over palladium nanoparticles(NPs).Benefiting from their unique structural merits that lead to significant lowering of the entropic barrier for FA activation,the Pd NPs interiorly located on the amino-modified MCM-41 offer the promise of more than an order of magnitude speedup of the initial activity in H2 production from FA over their exterior analogs.Under mild and additive-free conditions,ultrafine Pd NPs confined in aminomodified MCM-41 channels exhibit an initial turnover frequency as high as 46,677 h-1 and a turnover number up to 1,060,000 at 60℃.In conjunction with the enhancement and robust performance for efficient regeneration of FA via CO2 hydrogenation,the presented approach greatly contributes to the development of FA-based hydrogen storage and related technologies as viable means of enabling sustainable future energy prospects.
基金The National Natural Science Foundation of China under contract No.42006037the Chinese Polar Environmental Comprehensive Investigation&Assessment Programs,Grant from the Scientific Research Fund of the Second Institute of Oceanography,MNR under contract No.JB904the National Key R&D Program of China under contract No.2019YFC1509102。
文摘Oceanic vertical mixing of the lower halocline water(LHW)in the Chukchi Borderland and Mendeleyev Ridge was studied based on in situ hydrographic and turbulent observations.The depth-averaged turbulent dissipation rate of LHW demonstrates a clear topographic dependence,with a mean value of 1.2×10^(-9) W/kg in the southwest of Canada Basin,1.5×10^(-9) W/kg in the Mendeleyev Abyssal Plain,2.4×10^(-9) W/kg on the Mendeleyev Ridge,and2.7×10^(-9) W/kg on the Chukchi Cap.Correspondingly,the mean depth-averaged vertical heat flux of the LHW is0.21 W/m^(2) in the southwest Canada Basin,0.30 W/m^(2) in the Mendeleyev Abyssal Plain,0.39 W/m^(2) on the Mendeleyev Ridge,and 0.46 W/m^(2) on the Chukchi Cap.However,in the presence of Pacific Winter Water,the upward heat released from Atlantic Water through the lower halocline can hardly contribute to the surface ocean.Further,the underlying mechanisms of diapycnal mixing in LHW—double diffusion and shear instability—was investigated.The mixing in LHW where double diffusion were observed is always relatively weaker,with corresponding dissipation rate ranging from 1.01×10^(-9) W/kg to 1.57×10^(-9) W/kg.The results also show a strong correlation between the depth-average dissipation rate and strain variance in the LHW,which indicates a close physical linkage between the turbulent mixing and internal wave activities.In addition,both surface wind forcing and semidiurnal tides significantly contribute to the turbulent mixing in the LHW.