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Co-editing PINK1 and DJ-1 Genes Via Adeno-Associated Virus-Delivered CRISPR/Cas9 System in Adult Monkey Brain Elicits Classical Parkinsonian Phenotype 被引量:8
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作者 Hao Li Shihao Wu +13 位作者 Xia Ma Xiao Li Tianlin Cheng Zhifang Chen Jing Wu Longbao Lv Ling Li Liqi Xu Wenchao Wang Yingzhou Hu Haisong Jiang Yong Yin Zilong Qiu Xintian Hu 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第9期1271-1288,共18页
Whether direct manipulation of Parkinson’s disease(PD)risk genes in the adult monkey brain can elicit a Parkinsonian phenotype remains an unsolved issue.Here,we used an adeno-associated virus serotype 9(AAV9)-deliver... Whether direct manipulation of Parkinson’s disease(PD)risk genes in the adult monkey brain can elicit a Parkinsonian phenotype remains an unsolved issue.Here,we used an adeno-associated virus serotype 9(AAV9)-delivered CRISPR/Cas9 system to directly co-edit PINK1 and DJ-1 genes in the substantia nigras(SNs)of two monkey groups:an old group and a middle-aged group.After the operation,the old group exhibited all the classic PD symptoms,including bradykinesia,tremor,and postural instability,accompanied by key pathological hallmarks of PD,such as severe nigral dopaminergic neuron loss(>64%)and evidentα-synuclein pathology in the gene-edited SN.In contrast,the phenotype of their middle-aged counterparts,which also showed clear PD symptoms and pathological hallmarks,were less severe.In addition to the higher final total PD scores and more severe pathological changes,the old group were also more susceptible to gene editing by showing a faster process of PD progression.These results suggested that both genetic and aging factors played important roles in the development of PD in the monkeys.Taken together,this system can effectively develop a large number of genetically-edited PD monkeys in a short time(6–10 months),and thus provides a practical transgenic monkey model for future PD studies. 展开更多
关键词 Parkinson’s disease MONKEY Adeno-associated virus-delivered CRISPR/Cas9 PINK1 DJ-1 Parkinsonian phenotype
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Effects of sub-solvus ageing on the tensile and creep properties of a new cast nickel-based superalloy 被引量:1
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作者 Peng-Fei Zhao Kun-Lei Hou +3 位作者 Min Wang Mei-Qiong Ou Ya-qian Yang Ying-Che Ma 《Journal of Materials Science & Technology》 2025年第9期289-302,共14页
For nickel-based superalloys with medium volume-fractionγʹphase(20%-40%),dual or multi-stage aging treatments are usually conducted to generate a microstructure containing the multimodal distri-bution ofγʹfor a bala... For nickel-based superalloys with medium volume-fractionγʹphase(20%-40%),dual or multi-stage aging treatments are usually conducted to generate a microstructure containing the multimodal distri-bution ofγʹfor a balance of strength and plasticity.In the present study,the microstructure and high-temperature properties of a novel cast nickel-based superalloy K4800 were investigated after being sub-jected to three heat treatments(HT)procedures,namely HT1:1180℃/4 h+1090℃/2 h+800℃/16 h,HT2:1180℃/4 h+1060℃/2 h+800℃/16 h and HT3:1180℃/4 h+800℃/16 h.It was found that the sub-solvus aging treatments at 1090 and 1060℃ precipitated sub-micron-sized(∼300 nm)primaryγʹphase which enhanced the ductility during 800℃ tensile(the total elongation of T1,T2,and T3 sam-ples were 6.75%,7.3%,and 3.25%,respectively)without evidently impairing the strength.After careful microstructure observation and deformation mechanism analysis,the enhancement of elongation was ra-tionalized that the precipitation of the sub-micron-sized primaryγʹphase decreased the volume-fraction and size of the nanometer-sizedγʹphase which was precipitated at 800℃,and simultaneously,pro-moted the dislocation movement by suppressing the non-planar slip.However,an excessive amount of the sub-micron-sized primaryγʹphase led to a faster ripening process of the nanometer-sizedγʹduring creep,which decreased the creep life at 800℃/430 MPa(T1:125 h,T2:199 h,and T3:198 h).Based on this,we monitored the number density of nanometer-sizedγʹphase coexisting with different amounts of largeγʹduring creep.An area fraction less than 7%of the sub-micron-sizedγʹphase was considered to have little detrimental effect on the creep life of K4800 alloy,which corresponded to a sub-solvus temperature range about 1080-1090℃. 展开更多
关键词 Nickel-base superalloy Heat treatment Mechanical property Precipitation strengthening Deformation mechanism
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Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing
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作者 Haolan Ren Fei Zheng +1 位作者 Tingwei Cao Qiang Wang 《Atmospheric and Oceanic Science Letters》 2025年第1期39-45,共7页
Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in c... Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate models.Previous studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC simulations.In this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its collapse.Through a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s variability.The traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of AMOC.The results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter slowly.However,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale. 展开更多
关键词 Recovery of AMOC 4×CO_(2) forcing Key parameter Parameter estimation Data assimilation Machine learning
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Neuronal guidance factor Sema3A inhibits neurite ingrowth and prevents chondrocyte hypertrophy in the degeneration of knee cartilage in mice,monkeys and humans 被引量:1
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作者 Shishu Huang Dashuang Gao +19 位作者 Zhenxia Li Hongchen He Xi Yu Xuanhe You Diwei Wu Ze Du Jiancheng Zeng Xiaojun Shi Qinshen Hu Yong Nie Zhong Zhang Zeyu Luo Duan Wang Zhihe Zhao Lingli Li Guanglin Wang Liping Wang Zongke Zhou Di Chen Fan Yang 《Bone Research》 2025年第1期75-90,共16页
Osteoarthritis(OA)is a degenerative joint disease accompanied with the loss of cartilage and consequent nociceptive symptoms.Normal articular cartilage maintains at aneural state.Neuron guidance factor Semaphorin 3A(S... Osteoarthritis(OA)is a degenerative joint disease accompanied with the loss of cartilage and consequent nociceptive symptoms.Normal articular cartilage maintains at aneural state.Neuron guidance factor Semaphorin 3A(Sema3A)is a membrane-associated secreted protein with chemorepulsive properties for axons.However,the role of Sema3A in articular cartilage is still not clear.In the present studies,we investigated the functions of Sema3A in OA development in mice,non-human primates,and patients with OA.Sema3A has a protective effect on cartilage degradation,validated by the organoid culture in vitro and confirmed in chondrocyte-specific Sema3A conditional knockout mice.We demonstrated that Sema3A is a key molecule in maintaining cartilage homeostasis from chondrocyte hypertrophy via activating the PI3K pathway.The potential usage of Sema3A for OA treatment was validated in mouse and Rhesus macaque OA models through intra-articular injection of Sema3A,and also in patients by administering Sema3A containing platelet-rich plasma into the knee joints.Our studies demonstrated that Sema3A exerts a critical role in inhibiting neurite ingrowth and preventing chondrocyte hypertrophy in cartilage,and could be potentially used for OA treatment. 展开更多
关键词 SEMA3A CARTILAGE HYPERTROPHY
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Attention-enhanced deep learning approach for marine heatwave forecasting
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作者 Yiyun Liu Le Gao Shuguo Yang 《Acta Oceanologica Sinica》 2025年第1期36-49,共14页
Marine heatwave(MHW)events refer to periods of significantly elevated sea surface temperatures(SST),persisting from days to months,with significant impacts on marine ecosystems,including increased mortality among mari... Marine heatwave(MHW)events refer to periods of significantly elevated sea surface temperatures(SST),persisting from days to months,with significant impacts on marine ecosystems,including increased mortality among marine life and coral bleaching.Forecasting MHW events are crucial to mitigate their harmful effects.This study presents a twostep forecasting process:short-term SST prediction followed by MHW event detection based on the forecasted SST.Firstly,we developed the“SST-MHW-DL”model using the ConvLSTM architecture,which incorporates an attention mechanism to enhance both SST forecasting and MHW event detection.The model utilizes SST data from the preceding 60 d to forecast SST and detect MHW events for the subsequent 15 d.Verification results for SST forecasting demonstrate a root mean square error(RMSE)of 0.64℃,a mean absolute percentage error(MAPE)of 2.05%,and a coefficient of determination(R^(2))of 0.85,indicating the model’s ability to accurately predict future temperatures by leveraging historical sea temperature information.For MHW event detection using forecasted SST,the evaluation metrics of“accuracy”,“precision”,and“recall”achieved values of 0.77,0.73,and 0.43,respectively,demonstrating the model’s capability to capture the occurrence of MHW events accurately.Furthermore,the attention-enhanced mechanism reveals that recent SST variations within the past 10 days have the most significant impact on forecasting accuracy,while variations in deep-sea regions and along the Taiwan Strait significantly contribute to the model’s efficacy in capturing spatial characteristics.Additionally,the proposed model and temporal mechanism were applied to detect MHWs in the Atlantic Ocean.By inputting 30 d of SST data,the model predicted SST with an RMSE of 1.02℃and an R^(2)of 0.94.The accuracy,precision,and recall for MHW detection were 0.79,0.78,and 0.62,respectively,further demonstrating the model’s robustness and usability. 展开更多
关键词 sea surface temperature forecasting marine heatwave event detection deep learning attention mechanism
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Efficient open-air and as-cast processed organic solar cells enabled by optimized block and surface morphology using a low-cost terpolymer donor with enhanced dielectric constant
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作者 Zhenyu Li Xiaolei Kong +9 位作者 Jinyuan Zhang Panpan Zhang Aoxiang Li Xixi Zhang Xinrui Li Mingqi Tan Jing Li Haijun Bin Yongfang Li Chenkai Sun 《Nano Research》 2025年第12期480-488,共9页
Fabricating organic solar cells(OSCs)in open-air and room-temperature environments is essential for cost-effective roll-to-roll printing,but its performance is limited by non-ideal block and surface morphology of acti... Fabricating organic solar cells(OSCs)in open-air and room-temperature environments is essential for cost-effective roll-to-roll printing,but its performance is limited by non-ideal block and surface morphology of active layer.Herein,we demonstrate a record power conversion efficiency(PCE)of 19.72%in open-air and as-cast processed devices by using a lowcost terpolymer donor(PTQ20-5)to optimize the block and surface morphology.Compared with the counterpart PTQ10,PTQ20-5 shows increased hydrophobicity,which can better prevent the intrusion of H2O molecules in the film formation process in open-air environment,giving excellent humidity tolerance of corresponding devices.Moreover,the enhanced dielectric constant results in reduced exciton binding energy and improved charge transport of PTQ20-5,leading to improved charge separation and transfer,and suppressed carrier recombination in the devices.Besides,the PTQ20-5-based film has more appropriate block morphological features of balanced molecular self-assembly and phase separation,which simultaneously promotes the charge carrier transport and inhibits the carrier recombination at the donor/acceptor interface.This work is of great significance for promoting the industrialization of OSCs. 展开更多
关键词 organic solar cells open-air and as-cast processing low-cost polymer donors dielectric constant block and surface morphology
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Dynamic alterations in bacterial and fungal microbiome and inflammatory cytokines following SRV-8 infection in cynomolgus monkeys
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作者 Yun-Peng Yang Li-Bing Xu +3 位作者 Yong Lu Jing Wang Yan-Hong Nie Qiang Sun 《Zoological Research》 2025年第2期325-338,共14页
While viral infections can disturb the host gut microbiome,the dynamic alterations in microbial composition following infection remain poorly characterized.This study identified SRV-8-infected monkeys and classified t... While viral infections can disturb the host gut microbiome,the dynamic alterations in microbial composition following infection remain poorly characterized.This study identified SRV-8-infected monkeys and classified them into five groups based on infection progression.16S rRNA amplicon sequencing revealed significant alterations in the relative and inferred absolute abundance of bacterial genera UCG-002,Agathobacter,Coprococcus,and Holdemanella during the early stage of SRV-8 infection,coinciding with provirus formation.These microbial shifts were accompanied by functional modifications in bacterial communities at the same stage.In contrast,ITS amplicon sequencing indicated no significant differences in fungal composition between healthy wild-type and SRV-8-infected monkeys.Spearman correlation analyses demonstrated close interactions between intestinal bacteria and fungi following SRV-8 infection.Additionally,SRV-8 seropositive groups exhibited significantly elevated mRNA expression levels of pro-inflammatory(TNF-α,IFN-γ,IL-1β,and IL-6)and anti-inflammatory(IL-10)cytokine genes,highlighting close associations between inflammatory cytokines and immune responses.Overall,these findings provide a comprehensive characterization of bacterial and fungal microbiota dynamics and inflammatory cytokine responses associated with SRV-8 infection,clarifying the pathobiological mechanisms underlying SRV-8 infection from the perspective of the gut microbiome. 展开更多
关键词 Cynomolgus monkeys SRV-8 infection Dynamic alterations Bacterial and fungal microbes Inflammatory cytokines
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Prediction of New Functional Fluorooxoborates with Expected Anionic Framework:A Case of CaB_(3)O_(5)F
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作者 Ke-Wang Zhang Wen-Qi Jin +4 位作者 Ke Li Abudukadi Tudi Lin-Lin Liu Cong-Wei Xie Yu Xie 《Chinese Physics Letters》 2025年第3期85-92,共8页
The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging task.It has been suggested that the anionic... The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging task.It has been suggested that the anionic frameworks formed by B–O and B–O–F units significantly determine the physical properties of fluorooxoborates.Therefore,the rational design of anionic frameworks could facilitate the materials discovery process.Herein,we propose that a candidate anionic framework can be efficiently derived from an existing one by slightly altering its oxygen content.Following this idea,we hypothesized the existence of a 1D[B_(3)O_(5)F]_(∞)chain from the wellknown 2D[B_(6)O_(9)F_(2_)]_(∞)layer.Accordingly,seven CaB_(3)O_(5)F structures with the expected anionic framework were successfully predicted.First-principles calculations show that all these structures have potential in the UV/DUV birefringent or nonlinear optical(NLO)material field,indicating that the 1D[B_(3)O_(5)F]_(∞)chain is indeed a promising anionic framework for achieving UV/DUV birefringent and NLO performance. 展开更多
关键词 process BORATE ANIONIC
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Vascular Ossification in the Developing Brain:A Case Study of Pediatric Sturge Weber Syndrome
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作者 Ranxi Chen Shuhui Xie +7 位作者 Jin Gao Shuli Zhang Xiaobin Zhang Yi Yao Gengxiu Zheng Fengpeng Wang Zili Liu Xuefeng Shen 《Neuroscience Bulletin》 2025年第3期520-524,共5页
Dear Editor,Sturge-Weber Syndrome(SWS)is a rare congenital neurocutaneous syndrome[1,2],with an estimated prevalence of 0.19 in 100,000 annually[3].It is a non-hereditary disease linked to a somatic mutation in the GN... Dear Editor,Sturge-Weber Syndrome(SWS)is a rare congenital neurocutaneous syndrome[1,2],with an estimated prevalence of 0.19 in 100,000 annually[3].It is a non-hereditary disease linked to a somatic mutation in the GNAQ,GNA11,or GNB2 gene[1],leading to vascular malformations in the cutaneous forehead,cerebral cortex,and eye[1,2].Notably,~70%of pediatric patients diagnosed with SWS exhibit brain calcification(BC)[4],though the prevalence of BC ranges from only 1%in young individuals to>20%in the senior population(>60 years old)[5].Similar to the elderly,BC in pediatric SWS patients is identified as vascular calcification[6,7],whereas BC in pediatric patients with tuberous sclerosis and tumors has been previously described as dystrophic calcification[6]. 展开更多
关键词 vascular calcification vascular malformations brain calcification bc brain calcification congenital neurocutaneous syndrome somatic mutation vascular ossification Sturge Weber syndrome
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Iron-Involved ORR Electrocatalysts under the Lens of In-Situ/Operando Mössbauer Spectroscopy
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作者 Sumbal Farid Jun-Hu Wang 《电化学(中英文)》 北大核心 2026年第1期42-64,共23页
Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements hav... Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements have driven electrochem-ists to develop efficient ORR catalysts using abundant materials,particularly iron(Fe)-based,known for their exceptional performance in ORR.While the crucial function of Fe in boosting ORR catalytic activity is recognized,the connection between material attributes and catalytic performance remains enigmatic.Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts.Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis,facilitating the identification of active sites and the clarification of catalytic mechanisms.By showcasing noteworthy case studies within this review,we demonstrate the application of in-situ/operando 57Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis.This sheds light on various aspects of ORR catalysis,such as identifying active sites,assessing stability,and understanding the reaction mechanism.Our inquiry drives towards the opportunities and hurdles associ-ated with Mössbauer spectroscopy,unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm. 展开更多
关键词 Iron-based electrocatalyst In-situ/operando analysis Mössbauer spectroscopy Oxygen reduction reaction Structure-activity relationship
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Influence of Hf Alloying on Precipitation Behavior of γ' Phase and Tensile Properties of Ni-Cr-Mo Alloy
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作者 Li Linzi Guan Xianjun +1 位作者 Hou Jieshan Zhou Lanzhang 《稀有金属材料与工程》 北大核心 2026年第1期59-66,共8页
The influence of Hf on the precipitation behavior of γ'phase and the subsequent tensile properties of a Ni-Cr-Mo alloy after long-term thermal exposure was investigated.The results reveal that the addition of Hf ... The influence of Hf on the precipitation behavior of γ'phase and the subsequent tensile properties of a Ni-Cr-Mo alloy after long-term thermal exposure was investigated.The results reveal that the addition of Hf increases the average diameter ofγ'phases after thermal exposure at 700℃ for 5000 h,which enhances the critical resolved shear stress required for dislocations to shear the γ'phases in the Ni-Cr-Mo alloy.Simultaneously,element Hf incorporated into the γ'phases increases the lattice mismatch between the γ'and γ phase,thereby strengthening the coherency strengthening effect.These two factors collectively contribute to the enhanced strength of the alloy.Thus,Hf alloying effectively improves the yield strength of the Ni-Cr-Mo alloy after thermal exposure at 700℃. 展开更多
关键词 Ni-Cr-Mo alloy Hf alloying γ'strengthening long-term thermal exposure dislocations shearing
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A review of the standardized measurement of the characteristics of graphene-based materials
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作者 Zhang Donghui Li Wan +2 位作者 Ou Bingxian Wang Liangwang Ge Guanglu 《新型炭材料(中英文)》 北大核心 2026年第1期91-108,共18页
Standardization is necessary for the early industrialization of the new materials and technology.It is achieved by having agreed practices for the measurement of properties and other characteristics.The promising use ... Standardization is necessary for the early industrialization of the new materials and technology.It is achieved by having agreed practices for the measurement of properties and other characteristics.The promising use of graphene-based materials in fields like electronics,energy,and composites has resulted in standards for their nomenclature,the measurement of key characteristics,and their specification,etc.Among these,standards for measuring the key characteristics are crucial.The critical parameters are the number of layers,the type and concentration of defects and functional groups,elemental composition,sheet resistance,and carrier mobility.Standards for characterizing these have been analyzed by the International Organization for Standardization Technical Committee in ISO/TC229 and the International Electrotechnical Commission Technical Committee in IEC/TC113.These give details of applicable or preferred samples,the fundamental principles of the techniques,specific precautions,and points for attention in the relevant standards.The pivotal role of the ISO/TC229 and IEC/TC113 standards is considered and challenges and future trends are outlined. 展开更多
关键词 Nanotechnology Graphene-based materials Measurement standards Critical characteristics Quality control
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Ammonia Borane All‑In‑One Modification Strategy Enables High‑Performance Perovskite Solar Cells
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作者 Jiaxin Ma Cong Shao +6 位作者 Yirong Wang Guosheng Niu Kaiyi Yang Yao Zhao Fuyi Wang Zongxiu Nie Jizheng Wang 《Nano-Micro Letters》 2026年第3期463-478,共16页
Perovskite solar cells have achieved remarkable progress in photovoltaic efficiency.However,interfacial defects at the buried and upper interfaces of perovskite layer remain a critical challenge,leading to charge reco... Perovskite solar cells have achieved remarkable progress in photovoltaic efficiency.However,interfacial defects at the buried and upper interfaces of perovskite layer remain a critical challenge,leading to charge recombination,ion migration,and iodine oxidation.To address this,we propose a novel all-in-one modification strategy employing ammonia borane(BNH6)as a multifunctional complex.By incorporating BNH6 at both buried and upper interfaces simultaneously,we achieve dualinterfacial defect passivation and iodide oxidation suppression through three key mechanisms:(1)hydrolysis-induced interaction with SnO_(2),(2)coordination with Pb^(2+),and(3)inhibition of I−oxidation.This approach significantly enhances device performance,yielding a champion power conversion efficiency(PCE)of 26.43%(certified 25.98%).Furthermore,the unencapsulated device demonstrates prominent enhanced operation stability,maintaining 90%of its initial PCE after 500 h under continuous illumination.Notably,our strategy eliminates the need for separate interface treatments,streamlining fabrication and offering a scalable route toward high-performance perovskite photovoltaics. 展开更多
关键词 Ammonia borane All-in-one modification Multifunctional complex Perovskite solar cells
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Titanium-promoted conversion of N_(2) into N-methylimides
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作者 Rui Hu Yidan Qi +2 位作者 Xingyu Wang Yunhui Yang Congyang Wang 《Chinese Chemical Letters》 2026年第1期276-279,共4页
The direct transformation of dinitrogen(N_(2)) into nitrogen-containing organic compounds holds substantial importance.In this work,we report a titanium-promoted method for the conversion of N_(2) to N-methylimides.In... The direct transformation of dinitrogen(N_(2)) into nitrogen-containing organic compounds holds substantial importance.In this work,we report a titanium-promoted method for the conversion of N_(2) to N-methylimides.Initially,the N_(2)-bridging end-on dititanium side-on dipotassium complex[{(Tren^(TMS))Ti}_(2)(μ-η^(1):η^(1):η^(2):η^(2)-N_(2)K_(2))] underwent simultaneous disproportionation and N-methylation reactions in the presence of methyl trifluoromethanesulfonate(Me OTf),yielding [{(N^(Me,TMS)NN^(TMS)_(2))Ti}(μ-NMe)]_(2) with complete cleavage of the N≡N bond.The nucleophilicity of the N-methylated intermediate allowed it to react with electrophilic reagents such as trimethylchlorosilane(TMSCl) to form heptamethyldisilazane,or with acyl chlorides to generate N-methylimides.Moreover,nitrogen-15(^(15)N) labeled experiments provided a novel approach to synthesizing ^(15)N-labeled methylimides. 展开更多
关键词 Dinitrogen fixation TITANIUM IMIDES Heptamethyldisilazane DISPROPORTIONATION
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Enhancing C–N bond formation in amine carbonylation through dual hydrogen bonding catalysis under mild reaction conditions
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作者 Xiang Hui Jianhui Shi +4 位作者 Jiajun Zhang Yan Cao Huiquan Li Peng He Liguo Wang 《Green Energy & Environment》 2026年第1期236-247,共12页
The carbonylation of amines offers a promising route for synthesizing N-substituted carbamates with high atom economy.However,conventional catalysts exhibit limited catalytic efficiency,and the underlying proton trans... The carbonylation of amines offers a promising route for synthesizing N-substituted carbamates with high atom economy.However,conventional catalysts exhibit limited catalytic efficiency,and the underlying proton transfer mechanism remains elusive.Herein,we reported a metal-free,room-temperature strategy utilizing 1,5,7-triazabicyclo[4.4.0]dec-5-ene(TBD)as a dual hydrogen bond catalyst to synergistically activate propylamine(PA)and dimethyl carbonate(DMC).This green catalytic system achieves a 10-fold acceleration in reaction rate compared to other hydrogen bonding catalysts under mild conditions.This is enabled by dual hydrogen bonding of TBD with PA and DMC,which facilitates rapid proton transfer and stabilizes tetrahedral intermediates.Theoretical calculations confirm that the dual hydrogen bond system significantly lowers activation energy compared to single hydrogen bond analogs.Furthermore,it was revealed that the hydrogen bonding network within the product is the primary factor responsible for the sluggish reaction rate.This study demonstrates the effectiveness of a dual hydrogen bond system in accelerating the carbonylation of amines and provides a green route to access carbamates. 展开更多
关键词 Dual hydrogen bonds Carbonylation reaction -C-N-bond Proton transfer Mild conditions
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Facile and scale-up synthesis of cyano-functionalized covalent organic frameworks for selective gold recovery
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作者 Bo Li Yuanzhe Cheng +8 位作者 Xuyang Ma Dongxu Zhao Yang Zhang Yongxing Sun Jia Chen Li Wu Liang Zhao Hongdeng Qiu Yujian He 《Chinese Chemical Letters》 2026年第1期514-519,共6页
The recovery of gold from waste electronic and electric equipment(WEEE) has gained great attention with the increased number of WEEE,because it can largely alleviate the pressure on the environment and resources.Coval... The recovery of gold from waste electronic and electric equipment(WEEE) has gained great attention with the increased number of WEEE,because it can largely alleviate the pressure on the environment and resources.Covalent organic frameworks(COFs) are ideal adsorbents for gold recovery owing to their large surface area,good stability,easily functionalized ability,periodic structures,and definitive nanopores.Herein,a cyano-functionalized COF(COF-CN) with high crystallinity was large-scale prepared under mild conditions for the recovery of gold.The introduction of cyano groups enable COF-CN to exhibit excellent gold recovery performance,which possesses fast adsorption kinetics,high cycling stability,and adsorption capacity up to 663.67 mg/g.Excitingly,COF-CN showed extremely high selectivity for gold ions,even in the presence of various competing cations and anions.The COF-CN maintained excellent selectivity and removal efficiency in gold recovery experiments from WEEE.The facile synthesis of COF-CN and its outstanding selectivity in actual samples make it an attractive opportunity for practical gold recovery. 展开更多
关键词 Cyano functionalization Gold recovery Covalent organic frameworks Waste electronic and electric equipment SELECTIVITY
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Synergistic additive engineering with sulfur-terminated Ti_(3)C_(2)T_(x)MXene towards efficient and stable perovskite solar cells
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作者 Zhe Wu Hui Li +1 位作者 Yuhang Bao Jizheng Wang 《Science China Materials》 2026年第3期1691-1697,共7页
Two-dimensional MXene Ti_(3)C_(2)T_(x)demonstrates great promise in perovskite solar cells(PSCs).Herein,sulfur-terminated Ti_(3)C_(2)T_(x)(S-Ti_(3)C_(2)T_(x))is developed by modifying Ti_(3)C_(2)T_(x)via a facile hydr... Two-dimensional MXene Ti_(3)C_(2)T_(x)demonstrates great promise in perovskite solar cells(PSCs).Herein,sulfur-terminated Ti_(3)C_(2)T_(x)(S-Ti_(3)C_(2)T_(x))is developed by modifying Ti_(3)C_(2)T_(x)via a facile hydrothermal method using thioacetamide.As a perovskite additive,S-Ti_(3)C_(2)T_(x)outperforms pristine Ti_(3)C_(2)T_(x)by(1)significantly promoting grain growth,enhancing carrier mobility,and reducing defect density;(2)optimizing energy level alignment to lower interfacial energy barriers and minimize interface non-radiative recombination;(3)stabilizing uncoordinated Pb2+and[PbI6]4-octahedra via Pb-S bonds while alleviating bulk lattice strain,as this Pb-S interaction exerts a“tape-like”effect.Based on this synergistic mechanism,PSCs with S-Ti_(3)C_(2)T_(x)achieve a champion efficiency of 25.51%—outperforming control(23.46%)and pristine Ti_(3)C_(2)T_(x)-based devices(24.54%)—with enhanced stability.This work highlights terminal group engineering as a critical strategy for advancing high-performance PSCs and their potential for emerging photovoltaic technologies. 展开更多
关键词 perovskite solar cells MXene sulfur-terminated ADDITIVE strain release
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Nucleation of Polymers in Nanopores and Nanocomposites with Nanoparticles/Nanosheets
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作者 Ming Wang Ye Yao +4 位作者 Hui Zhao Wei-Long Ju Yun-Lan Su Du-Jin Wang Guo-Ming Liu 《Chinese Journal of Polymer Science》 2026年第1期1-12,I0007,共13页
Nucleation,which is the initial step of crystallization,critically governs the polymer crystallization behavior,influencing the crystallization temperature,kinetics,and morphology.However,the direct observation of the... Nucleation,which is the initial step of crystallization,critically governs the polymer crystallization behavior,influencing the crystallization temperature,kinetics,and morphology.However,the direct observation of the nucleation process in polymers remains elusive owing to spatial and temporal resolution limitations.This feature article summarizes the recent progress in understanding polymer nucleation within confined and interface-dominated environments,focusing on three representative systems:anodic aluminum oxide templates and nanocomposites containing nanoparticles or nanosheets.The interplay between finite size and interfacial effects has revealed some novel phenomena,such as homogeneous nucleation,surface nucleation,prefreezing,and supernucleation. 展开更多
关键词 Homogeneous nucleation Surface nucleation Prefreezing Supernucleation Confinement effects
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Mechanical force-induced switchable multiple-color and white-light circularly polarized luminescence
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作者 Ruirui Ren Ying Pan +1 位作者 Han-Xiao Wang Minghua Liu 《Chinese Chemical Letters》 2026年第2期340-345,共6页
Achieving rational control over polarization states and color of circularly polarized luminescence(CPL)through simple modulation poses a challenging yet highly practical problem.To address this issue,we developed a me... Achieving rational control over polarization states and color of circularly polarized luminescence(CPL)through simple modulation poses a challenging yet highly practical problem.To address this issue,we developed a mechano-responsive chiral supramolecular system based on a cyclohexanediamide-derived gelator CCPy.This molecule exhibited a strong blue fluorescence accompanied by a distinct CPL signal upon forming a supramolecular gel in toluene.However,upon the application of mechanical force,the gel rapidly transformed into a faintly emissive suspension with a silent CPL signal,along with a notable morphological alteration.Furthermore,by implementing the circularly polarized Förster resonance energy transfer(CP-FRET)strategy,the mechano-responsiveness was effectively imparted to binary systems through the incorporation of dyes Nile red(NR)and coumarin 7(C7),thus realizing mechanical force-switchable green and red CPL systems.It was particularly noteworthy that by adjusting the ratio of CCPy,C7 and NR,a ternary mechanical force-induced CPL ON-OFF switch that emitted a standard white emission was achieved through sequential CP-FRET.Following this,an information encryption experiment was performed.This work provided a paradigm for fabricating smart multi-color and white-light CPL materials. 展开更多
关键词 Circularly polarized luminescence Mechano-responsiveness Supramolecular gel White-light emission Energy transfer
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A comparative study on the apatite and zircon from the ore-related and-barren magmatic rocks of the Shatanjiao region,Lower Yangtze River Belt:Controlling effects for petrogenesis and Cu-Au mineralization
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作者 Yu Wang Jing-ya Cao +4 位作者 Sheng-xiong Yang Xiao-yong Yang Majid Ghasemi Siani Asghar Dolati Muhammad Hafeez 《China Geology》 2026年第1期120-135,I0015-I0022,共24页
The links between the adakitic rocks and Cu-Au mineralization have long been argued.This study investigates petrogenesis and its link to mineralization potential by a series of in-situ geochronological and geochemical... The links between the adakitic rocks and Cu-Au mineralization have long been argued.This study investigates petrogenesis and its link to mineralization potential by a series of in-situ geochronological and geochemical signatures of apatite and zircon in three ore-related intrusions and one-barren intrusion in the Middle-Lower Yangtze River Metallogenic Belt(MLYRB).Zircon U-Pb dating yield ages of 139–143 Ma and 121 Ma for the ore-related and ore-barren intrusions,respectively.The ore-related rocks have higher apatite Sr/Y(1.57–9.69),(La/Yb)_(N)(16.7–159.5),andδEu(0.45–0.74)than the ore-barren rocks of 0.57–1.02,19.3–24.1 and 0.40–0.45,respectively,indicating the former has an adakitic affinity,while the latter has a non-adakitic affinity.The ore-related rocks have enriched zircon Hf isotopes withε_(Hf)(t)values of-15.9 to-5.5 and T_(DMC)ages of 2408–1655 Ma and apatite Sr-Nd isotopes,indicating that the ore-related magmas were mainly originated from partial melting of subducted oceanic crust.The orebarren rocks have higherε_(Hf)(t)values of-6.6 to-4.6 and lower T_(DMC)ages of 1598–1469 Ma and apatite Sr-Nd isotopes,indicating a lithospheric mantle source.The ore-related rocks have higher oxygen fugacity of mean∆FMQ+2.00 and X_(F)/X_(OH)of 8.36–175 than the ore-barren rocks of mean∆FMQ+1.43 and3.72–4.96.It was inferred that magma source,water content,and oxygen fugacity emerge as critical factors governing the regional Cu-Au mineralization potential. 展开更多
关键词 Sr-Nd-Hf isotopes Zircon U-Pb dating Apatite Sr-Nd isotopes Oxygen fugacity Magma source Adakitic rocks Cu-Au mineralization Shatanjiao Orefield
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