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Gunn器件中畴的静止-渡越-静止模式的实验观察和计算机模拟
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作者 王守武 郑一阳 +1 位作者 郗小林 张进昌 《Journal of Semiconductors》 EI CAS 1983年第4期321-333,共13页
本文讨论在GaAs n^+-n-n^+夹层结构的Cunn器件中畴的静止-渡越-静止模式,进行了实验观察和计算机模拟,指出在超过阈值的偏置电压下,当畴的耗尽层进入阳极附近的高掺杂区后,会逐渐停止下来形成准静态畴,这时畴外电场达到最大值.如果这时... 本文讨论在GaAs n^+-n-n^+夹层结构的Cunn器件中畴的静止-渡越-静止模式,进行了实验观察和计算机模拟,指出在超过阈值的偏置电压下,当畴的耗尽层进入阳极附近的高掺杂区后,会逐渐停止下来形成准静态畴,这时畴外电场达到最大值.如果这时阴极凹口仍不能形成新畴,则准静态畴将进一步调整成为真正的静止畴,而畴外电场也将由最大值下降到一个与偏压无关的固定值.经过理论分析,得到了静止畴所固有的与外加偏压无关的畴外电场与有源区掺杂浓度的关系式,并和计算机模拟的结果相比较,得到很好的符合.如果偏压的增加使准静态畴所对应的畴外电场最大值已经足够使阴极凹口形成新的畴,则静止畴将转变为渡越畴.如果偏压继续增加,使积累层尾部覆盖了阴极凹口,则畴会再次静止下来,直到偏压增加到畴发生雪崩为止.计算和实验表明,后一个静止区的电压变化范围要比前一个大得多.本文还讨论了两个转变电压和温度的关系及扩散系数对静止畴的影响. 展开更多
关键词 The TRAnSFORMATIOnS between stationary and TRAnSIT DOMAInS in a GUnn device which has n^+-n-n^+ SAnDWICH structure with doping gradient near the anode are investigated.Experimental observation computer simulation carried out.When th
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Realizing Stable Zigzag Polymeric Nitrogen Chains in P-N Compounds
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作者 Chengfeng Zhang Guo Chen +2 位作者 Yanfeng Zhang Jie Zhang Xianlong Wang 《Chinese Physics Letters》 2026年第3期316-330,共15页
The zigzag nitrogen chain,similar to the Ch-N structure,has long been considered as a potential high-energy-density structure.However,all the previously predicted zigzag N-chain structures,similar to Ch-N,exhibited im... The zigzag nitrogen chain,similar to the Ch-N structure,has long been considered as a potential high-energy-density structure.However,all the previously predicted zigzag N-chain structures,similar to Ch-N,exhibited imaginary frequencies in their phonon spectra at 0 GPa.Here,we conducted a systematic investigation of P-N compounds using first-principles calculations,uncovering a series of structurally similar stable phases,C2/m-PN_(x)(x=6,8,10,12,and 14),in which N forms zigzag N chains similar to those in Ch-N.In P-N compounds,the longest zigzag N-chain,which can theoretically remain stable under ambient pressure,is the N-chain composed of 14 N atoms in C2/m-PN14.If the N-chain continues to grow,imaginary interchain vibrational frequencies arise in the system.Notably,N chains with an even number of atoms were more likely to be energetically favorable.The five C2/m-PN_(x) phases and one metastable phase(R-PN_(6))exhibited remarkable stability and excellent detonability at ambient pressure,indicating that they are promising candidates for high-energy-density materials.In addition,R-PN_(6) was the first structure to stabilize the N_(6) ring through covalent bonding,with the covalent network contributing to its high hardness(47.59 GPa). 展开更多
关键词 p n compounds phonon spectra imaginary frequencies high energy density materials zigzag n chains zigzag nitrogen chainsimilar stable zigzag polymeric nitrogen chains first principles calculations
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Fat mass and obesity-mediated N^(6)-methyladenosine modification modulates neuroinflammatory responses after traumatic brain injury
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作者 Xiangrong Chen Jinqing Lai +4 位作者 Zhe Wu Jianlong Chen Baoya Yang Chunnuan Chen Chenyu Ding 《Neural Regeneration Research》 2026年第2期730-741,共12页
The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiqui... The neuroinflammatory response mediated by microglial activation plays an important role in the secondary nerve injury of traumatic brain injury.The post-transcriptional modification of N^(6)-methyladenosine is ubiquitous in the immune response of the central nervous system.The fat mass and obesity-related protein catalyzes the demethylation of N^(6)-methyladenosine modifications on mRNA and is widely expressed in various tissues,participating in the regulation of multiple diseases’biological processes.However,the role of fat mass and obesity in microglial activation and the subsequent neuroinflammatory response after traumatic brain injury is unclear.In this study,we found that the expression of fat mass and obesity was significantly down-regulated in both lipopolysaccharide-treated BV2 cells and a traumatic brain injury mouse model.After fat mass and obesity interference,BV2 cells exhibited a pro-inflammatory phenotype as shown by the increased proportion of CD11b^(+)/CD86^(+)cells and the secretion of pro-inflammatory cytokines.Fat mass and obesity-mediated N^(6)-methyladenosine demethylation accelerated the degradation of ADAM17 mRNA,while silencing of fat mass and obesity enhanced the stability of ADAM17 mRNA.Therefore,down-regulation of fat mass and obesity expression leads to the abnormally high expression of ADAM17 in microglia.These results indicate that the activation of microglia and neuroinflammatory response regulated by fat mass and obesity-related N^(6)-methyladenosine modification plays an important role in the pro-inflammatory process of secondary injury following traumatic brain injury. 展开更多
关键词 ADAM17 epigenetic modification fat mass and obesity n6-methyladenosine MICROGLIA mRnA nerve injury nEUROInFLAMMATIOn traumatic brain injury tumor necrosis factorα
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Ultrahigh strength of cage-like polymeric nitrogen surpassing diamond under high pressure
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作者 Hui Liang Di Wang +4 位作者 Rui Xu Hao Chen Dan Zhou Yunwei Zhang Quan Li 《Matter and Radiation at Extremes》 2026年第1期103-110,共8页
We report first-principles predictions of a cage-like polymeric nitrogen phase(cage-N)composed of interlocked N10 clusters stabilized by mixed sp^(2)/sp^(3) hybridization.Under high pressure,cage-N exhibits exceptiona... We report first-principles predictions of a cage-like polymeric nitrogen phase(cage-N)composed of interlocked N10 clusters stabilized by mixed sp^(2)/sp^(3) hybridization.Under high pressure,cage-N exhibits exceptional mechanical performance,including an ideal compressive strength of 343 GPa at a pressure of 300 GPa,~33% higher than that of diamond.This ultrahigh strength arises from the synergistic interplay between its three-dimensional covalent framework and hybridized bonding topology,which enables isotropic stress accommodation and dynamic electronic rearrangement.These results establish cage-N as a promising non-carbon ultrahard material and provide a bonding-driven route toward designing superhard frameworks under extreme conditions. 展开更多
关键词 compressive strength mixed sp sp hybridization cage polymeric nitrogen hybridized bonding topologywhich mechanical performance interlocked n clusters ultrahigh strength first principles predictions
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Model of Universe as Described by Dynamic Universe Model
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作者 Satyavarapu Naga Parameswara Gupta 《Open Journal of Modelling and Simulation》 2019年第1期41-78,共38页
In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the m... In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis. 展开更多
关键词 DYnAMIC UnIVERSE MODEL Hubble Space Telescope (HST) SITA Simulations (SITA-Simulation of Inter Intra Tautness Attraction Forces Used by DYnAMIC UnIVERSE Model) Singularity-Free COSMOLOGY Blue Shifted GALAXIES Red Shifted GALAXIES Grazing Radiation Frequency Changes Formation of Elements nucleosynthesis DYnAMIC UnIVERSE MODEL Energy to Mass Conversion Methods: n-Body Simulations-Gravitation-Cosmology
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Co-circulation of H3N2 canine influenza and distemper viruses in canine populations from Liaoning,China
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作者 Siqi Tang Yaoqi Wang +4 位作者 Xiaorui Zhang Hailing Li Haoyu Leng Yali Feng Ying Zhang 《Journal of Integrative Agriculture》 2026年第2期824-827,共4页
Influenza A virus(IAV) has a wide host range,including wild birds,poultry,various mammals,and even humans(Xu et al.2024).Currently,two subtypes of canine influenza virus(CIV),H3N8 and H3N2,are primarily circulating in... Influenza A virus(IAV) has a wide host range,including wild birds,poultry,various mammals,and even humans(Xu et al.2024).Currently,two subtypes of canine influenza virus(CIV),H3N8 and H3N2,are primarily circulating in dogs.The H3N8 CIV was introduced from horses into dogs in 2004(Crawford et al.2005),while the H3N2 CIV originated from chickens in Asia in 2007(Song et al.2008).In China,H3N2 is the predominant CIV subtype,with a prevalence rate of up to 5.63% in the canine population,as reported by Chen et al.(2023).CIV infection typically manifests with symptoms such as coughing,sneezing,runny nose,and fever but is rarely fatal.However,co-infection with other pathogens(e.g.,Streptococcus,Mycoplasma or canine parainfluenza virus) can exacerbate symptoms and lead to lethal outcomes(Yondo et al.2023). 展开更多
关键词 influenza virus iav canine influenza virus distemper virus co infection China co circulation h n canine influenza virus civ h n
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Hexagonal B-C-N composite consisting of h-BN and graphite separated by B-C nanolayer
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作者 Baoyin Xu Xiaohong Yuan +10 位作者 Bingtao Feng Yifeng Jiang Yaqi She Zhanhui Ding Yue Pan Shucheng Liu Kuo Hu Zhaodong Liu Quanjun Li Bingbing Liu Hu Tang 《Matter and Radiation at Extremes》 2026年第2期85-94,共10页
Graphite and hexagonal boron nitride(h-BN),despite their structural similarity,exhibit opposing electronic properties,namely,metallic conductivity and wide-bandgap insulation,respectively.In recent years,graphene-h-BN... Graphite and hexagonal boron nitride(h-BN),despite their structural similarity,exhibit opposing electronic properties,namely,metallic conductivity and wide-bandgap insulation,respectively.In recent years,graphene-h-BN heterostructures have attracted significant research interest,with the resulting hybrid B-C-N atomic-layer systems exhibiting distinctive electronic properties.Notably,interface effects play a decisive role in governing the performance of these heterostructures.Nevertheless,owing to the lack of high-quality composites,the interfacial structure in B-C-N materials and the correlation with critical properties such as charge transport and band structure modulation are not fully clear.Here,we report the direct synthesis of a millimeter-sized hexagonal B-C-N composite via a solvent method under high-pressure and high-temperature conditions.Structural characterization reveals that the synthesized B-C-N composite contains isolated graphite and h-BN.Compared with pure h-BN,the B-C-N composite has a narrower bandgap and shows a pronounced photoelectric response in the visible light region.More interestingly,we find a graphite-like B-C compound with a thickness of about 30 nm at the graphite-h-BN interface,which forms Schottky junctions with graphite,thus realizing rectification properties.Our findings provide a method for synthesizing highquality B-C-N composites and offer new insights into the structure of the graphite-h-BN interface. 展开更多
关键词 GRAPHITE photoelectric response electronic propertiesnotablyinterface effects high pressure high temperature synthesis hexagonal boron nitride interface effects hexagonal b c n composite Schottky junction
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Glycine decarboxylase as a novel regulator of N-methyl-D-aspartate receptor function:Implications for pathophysiology of schizophrenia
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作者 Maltesh Kambali Uwe Rudolph 《Neural Regeneration Research》 2026年第7期2950-2951,共2页
Glutamate receptors and schizophrenia:Schizophrenia is a chronic mental disorder affecting approximately 1%of the global population,with 70%-80%heritability.It has a multifactorial etiology involving both environmenta... Glutamate receptors and schizophrenia:Schizophrenia is a chronic mental disorder affecting approximately 1%of the global population,with 70%-80%heritability.It has a multifactorial etiology involving both environmental factors and a complex polygenic genetic architecture.Over the last two decades,large-scale genome-wide approaches revealed contributions of common variants with individually small effect sizes and of rare copy number variants with a large effect size.N-methy l-D-a spar tat e receptor(NMDAR)hypofunction has been implicated as a central mechanism in the pathophysiology of schizophrenia(Coyle et al.,2020). 展开更多
关键词 n methyl D aspartate receptor SCHIZOPHREnIA polygenic genetic architectureover glycine decarboxylase PATHOPHYSIOLOGY common variants glutamate receptors chronic mental disorder
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Pattern of disharmony between the heart and kidney: Theoretical basis, identification and treatment 被引量:1
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作者 Jian Dong Tianfang Wang +1 位作者 Lihong Zhao Xinran Chen 《Journal of Traditional Chinese Medical Sciences》 2017年第4期317-321,共5页
'Harmony between the heart and kidney' refers to the physiological relationship between these two zang organs in Chinese medicine,while 'disharmony between the heart and kidney' (also called disharmony... 'Harmony between the heart and kidney' refers to the physiological relationship between these two zang organs in Chinese medicine,while 'disharmony between the heart and kidney' (also called disharmony between fire and water) refers to the pathological state.The pattern of disharmony between the heart and kidney is widely observed in patients with insomnia,anxiety disorder and menopausal syndrome,etc..In order to gain a full and systematical understanding of this pattern,from the perspective of ancient Chinese philosophy and zang-fu theory in Chinese medicine,we systematically reviewed and discussed the functions and physiological characteristics of the heart and kidney,the origin and development of theories relating to heart-kidney relationship,the pathogenesis and identification of the pattern,as well as the commonly used classical formulas for its treatment,including Coptis and DonkeyHide Gelatin Decoction (Huánglián (E)jiāo Tāng) and Grand Communication Pill (Jiāotài Wán).Two examples of clinical modifications of these formulas in the treatment of insomnia and menopausal syndrome are provided in this article.It should be noted that in clinical practice,these formulas should be used flexibly,and modified in accordance to the condition of the patient. 展开更多
关键词 Harmony BETWEEn the HEART and KIDnEY Disharmony BETWEEn the HEART and KIDnEY PATTERn of disharmony BETWEEn the HEART and KIDnEY Coptis and Donkey-Hide Gelatin Decoction (Huánglián (E)jiāo ng) Grand Communication Pill (Jiāotài n)
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Optical properties for N,N’-bis (lnaphyhly)N,N’-diphenyl-1,1’-biphenyl-4,4’-diamine and tris (8-hydroxyquinolinato) aluminum in organic light emitting devices 被引量:1
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作者 Mei Yee Lim Wan Mahmood Mat Yunus +1 位作者 Zainal Abidin Talib Anuar Kassim 《Natural Science》 2010年第6期631-634,共4页
The optical properties of N,N’-bis (Inaphthyl)N,N’-diphenyl-1,1’-biphenyl-4,4’-diamine (NPB) and tris (8-hydroxyquinolinato) aluminum (Alq3) organic materials used as hole transport and electron transport layers i... The optical properties of N,N’-bis (Inaphthyl)N,N’-diphenyl-1,1’-biphenyl-4,4’-diamine (NPB) and tris (8-hydroxyquinolinato) aluminum (Alq3) organic materials used as hole transport and electron transport layers in organic light-emitting devices (OLED) have been investigated. The NPB and Alq3 layers were prepared using thermal evaporation method. The results show that the energy band gap of Alq3 is thickness independence while the energy band gap of NPB decreases with the increasing of sample thickness. For the case of photoluminescence the Alq3 with thickness of 84 nm shows the highest relative intensity peak at 510 nm. 展开更多
关键词 Energy Band Gap n n’-Bis (Inaphthyl) -n n’-Diphenyl-1 1’-Biphenyl-4 4’-Diamine Tris (8 Hydroxyquinolinato) Aluminum Organic Light Emitting Diode Photoluminescence
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Soil nitrogen dynamics regulate differential nitrogen uptake between rice and upland crops
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作者 Shending Chen Ahmed S.Elrys +5 位作者 Siwen Du Wenyan Yang Zucong Cai Jinbo Zhang LeiMeng Christoph Müller 《Journal of Integrative Agriculture》 2026年第1期302-312,共11页
Nitrogen use efficiency in rice is lower than in upland crops,likely due to differences in soil nitrogen dynamics and crop nitrogen preferences.However,the specific nitrogen dynamics in paddy and upland systems and th... Nitrogen use efficiency in rice is lower than in upland crops,likely due to differences in soil nitrogen dynamics and crop nitrogen preferences.However,the specific nitrogen dynamics in paddy and upland systems and their impact on crop nitrogen uptake remain poorly understood.The N dynamics and impact on crop N uptake determine the downstream environmental pollution from nitrogen fertilizer.To address this poor understanding,we analyzed 2,044 observations of gross nitrogen transformation rates in soils from 136 studies to examine nitrogen dynamics in both systems and their effects on nitrogen uptake in rice and upland crops.Our findings revealed that nitrogen mineralization and autotrophic nitrification rates are lower in paddies than in upland soil,while dissimilatory nitrate reduction to ammonium is higher in paddies,these differences being driven by flooding and lower total nitrogen content in paddies.Rice exhibited higher ammonium uptake,while upland crops had over twice the nitrate uptake.Autotrophic nitrification stimulated by p H reduced rice nitrogen uptake,while heterotrophic nitrification enhanced nitrogen uptake of upland crops.Autotrophic nitrification played a key role in regulating the ammonium-to-nitrate ratio in soils,which further affected the balance of plant nitrogen uptake.These results highlight the need to align soil nitrogen dynamics with crop nitrogen preferences to maximize plant maximize productivity and reduce reactive nitrogen pollution. 展开更多
关键词 paddy soil upland soil plant nitrogen uptake n mineralization nITRIFICATIOn ^(15)n tracing study
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Entropy-Controlled Exsolution of Highly Dispersed Nickel-Based Active Metals From Spinel Oxide via Optimizing Metal-Support Interaction for Dry Reforming of Methane
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作者 Yuxuan Meng Yuefan Tuo +8 位作者 Yao Xue Xiaofeng Yan Zhengkun Luo Qianrui Yang Stanislav Chernyshikhin Yilong Yan Meng Lin Yufei Zhao Xianguang Meng 《Carbon Energy》 2026年第2期132-143,共12页
Sintering and coking are critical barriers to achieving high performance in dry reforming of methane(DRM)catalysts.A finely dispersed and thermostable Ni-based catalyst is the key to address these issues.By leveraging... Sintering and coking are critical barriers to achieving high performance in dry reforming of methane(DRM)catalysts.A finely dispersed and thermostable Ni-based catalyst is the key to address these issues.By leveraging the intrinsic superiorities of high-entropy oxides in high-temperature stability and low atomic diffusivity,in this study,a highly dispersed Ni-based catalyst is synthesized via an entropycontrolled exsolution of active components.By increasing the number of transition-metal elements in spinel oxides,the active metalsupport interaction(MSI)can be continuously strengthened,which controls the exsolution and thermal stability of Ni-based active metal in harsh reaction conditions of DRM.An optimized medium-entropy spinel(Mg_(0.4)Ni_(0.2)Co_(0.2)Zn_(0.2))Al_(2)O_(4)with the exsolution of finely dispersed Ni–Co nanoparticles displayed superior activity and stability in thermal DRM at 800°C and photothermal DRM.This entropy-controlled MSI and exsolution principle provides a significant strategy for designing robust catalysts resistant to sintering and coking for high-temperature reactions like DRM in thermal and photothermal systems. 展开更多
关键词 dry reforming of methane EXSOLUTIOn high‐entropy n icatalyst SPInEL
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MAPT-isoform 0N3R is essential for human brain development:Loss-of-function for novel TAU-associated disease paradigms
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作者 Hans Zempel 《Neural Regeneration Research》 2026年第8期3349-3351,共3页
Hans Zempel1,2 TAU,a microtubule-associated protein,encoded by the microtubule-associated protein tau(MAPT)gene,is a central regulator of microtubule stability and axonal function in the human brain,with its pathologi... Hans Zempel1,2 TAU,a microtubule-associated protein,encoded by the microtubule-associated protein tau(MAPT)gene,is a central regulator of microtubule stability and axonal function in the human brain,with its pathological aggregation representing a hallmark of Alzheimer’s disease and related tauopathies.Despite extensive research into the role of TAU in neurodegeneration,its essentiality for human brain development has remained unclear.This perspective synthesizes recent genetic,molecular,and cellular evidence to demonstrate that the human brain-specific TAU isoform 0N3R is indispensable for proper neurodevelopment,pointing to loss-of-function of this isoform as a novel paradigm for TAU-associated disease.Alternative splicing of MAPT generates six brain-specific TAU isoforms,with 0N3R being exclusively expressed during fetal brain development.Analysis of large-scale human genetic datasets(gnomAD v4.0.0)reveals a high probability of loss-of-function intolerance(pLI=0.96)for the 0N3R isoform.This is in stark contrast to the canonical Matched Annotation from the NCBI and EMBL-EBI(MANE)transcript and peripheral“Big TAU,”both of which are tolerant to loss-of-function mutations.This intolerance is further supported by the scarcity of loss-of-function mutations in 0N3R-encoding exons and high missense constraint scores,suggesting strong evolutionary selection against disruption of this isoform.Functional studies using human induced pluripotent stem cell-derived cortical neurons with CRISPR-Cas9-mediated MAPT knockout reveal that,unlike in murine models where compensation by other microtubule-associated proteins occurs,loss of TAU in human neurons leads to deficits in neurite outgrowth,axon initial segment shortening,and a trend toward hyperexcitability,accompanied by broad transcriptomic changes affecting genes involved in microtubule organization and synaptic structure.Remarkably,re-expression of any of the six human brain-specific TAU isoforms rescues these phenotypes,underscoring their functional redundancy during development.These findings position the 0N3R isoform as essential for human brain development and suggest that loss-of-function mutations affecting this isoform likely result in neurodevelopmental impairment,potentially manifesting as intellectual disability without overt dysmorphic features.This contrasts with the apparent tolerance to MAPT loss-of-function in mice and peripheral tissues,highlighting a critical species-and isoform-specific requirement for TAU in human neurodevelopment.The hypothesis of 0N3R-TAU loss-of-function intolerance opens new avenues for understanding neurodevelopmental disorders and refines the conceptual framework of TAU-associated disease mechanisms beyond toxic gain-of-function. 展开更多
关键词 0n3R isoform alternative splicing Alzheimer’s disease intellectual disability neurodevelopmental disorders TAU protein TAUOPATHY
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High-electronegativity N stabilized amorphous Mo–Se coordination via local electronic domains for boosting sodium-ion storage in hybrid capacitors
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作者 Bowen Liao Wenxiu He +5 位作者 Gaojin Su Fanyan Zeng Yang Pan Dui Ma Li Zhang Xinman Tu 《Journal of Energy Chemistry》 2026年第3期657-666,共10页
In sodium-ion hybrid capacitors(SIHCs),the high-capacity metal selenide anodes are severely limited by structural instability and polyselenide dissolution/shuttle during cycling.This study proposes an innovative strat... In sodium-ion hybrid capacitors(SIHCs),the high-capacity metal selenide anodes are severely limited by structural instability and polyselenide dissolution/shuttle during cycling.This study proposes an innovative strategy utilizing high-electronegativity N(χ=3.04)to modulate local electronic domains and stabilize amorphous Mo–Se coordination(N/Mo-Se).Through self-polymerization and tunable selenization,N-doped carbon(NC)nanospheres encapsulating N-stabilized amorphous Mo-Se clusters(N/Mo-Se@NC)are successfully constructed.Theoretical and experimental analyses reveal that N-optimization effectively reconstructs the electronic distribution of Mo–Se coordination via strong covalent Mo–N bonds.This significantly enhances the covalency of Mo-Se clusters and induces localized electronic domains,thereby substantially suppressing polyselenide dissolution/shuttle during cycling.Concurrently,the amorphous N/Mo-Se clusters provide isotropic ion diffusion pathways,and together with the threedimensional(3D)conductive networks of the NC,they jointly optimize charge transfer kinetics.The N/Mo-Se@NC anode exhibits a high reversible capacity of 328.7 mAh g^(-1)after 5000 cycles,even at 10.0 A g^(-1),with a remarkable capacity retention of 110%.The assembled N/Mo-Se@NC//AC SIHCs achieve high energy/power densities(236.1 Wh kg^(-1)/9990 W kg^(-1)),demonstrating superior comprehensive performance compared to most previously reported anodes.This study,through high-electronegativity atom modulation and amorphization engineering,opens new avenues for designing highly stable and high-rate Na^(+) storage materials. 展开更多
关键词 High-electronegativity n modulation Local electronic domain reconstruction Amorphous Mo–Se coordination Polyselenide dissolution suppression Sodium-ion hybrid capacitors
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Electrocatalytic urea synthesis from HCOOH and NO_(3)^(-)on Fe-Pd dual atoms
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作者 Ruixuan Yang Chaofan Qiang +2 位作者 Yali Guo Yubiao Li Ke Chu 《Journal of Energy Chemistry》 2026年第2期995-1003,I0020,共10页
Conventional electrocatalytic urea synthesis via CO_(2)+N_(2) or CO_(2)+NO_(3)^(-)coelectrolysis generally suffers from poor reactants coactivation,low C-N coupling efficiency,and serious competing reactions.To overco... Conventional electrocatalytic urea synthesis via CO_(2)+N_(2) or CO_(2)+NO_(3)^(-)coelectrolysis generally suffers from poor reactants coactivation,low C-N coupling efficiency,and serious competing reactions.To overcome these limitations,we implement HCOOH+NO_(3)^(-)coelectrolysis to urea using a Fe-Pd dual-atom catalyst(Fe_(1)Pd_(1)-DAC).Operando spectroscopic measurements and theoretical computations collectively reveal that Pd_(1) selectively dehydrogenates HCOOH to^(*)COOH,while Fe_(1) selectively activates NO_(3)^(-)to^(*)NH_(2).Specifically,the spatial proximity and electrophilic-nucleophilic synergy of^(*)COOH and^(*)NH_(2) enable the high C-N coupling efficiency and well-suppressed competing reactions.Consequently,Fe_(1)Pd_(1)-DAC assembled in a flow cell delivers the unprecedented urea yield rate up to 448.1 mmol h^(-1) g^(-1) and Faradaic efficiency of 78.3%at an industrial-level current density of-215 mA cm^(-2),far outperforming those obtained from CO_(2)+N_(2) or CO_(2)+NO_(3) coelectrolysis.Further techno-economic analysis demonstrates Fe_(1)Pd_(1)-DAC as a promising catalyst for economically feasible urea production via HCOOH+NO_(3)^(-)coelectrolysis. 展开更多
关键词 HCOOH+nO_(3)−coelectrolysis Urea electrosynthesis C–n coupling Dual-atom catalysts Operando spectroscopic measurements Theoretical calculations
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基于改进YOLOv8n的煤矿巷道异常管路智能识别方法
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作者 毛清华 王俞 +2 位作者 薛旭升 周通 苏毅楠 《工矿自动化》 北大核心 2026年第3期63-72,共10页
针对现有异常管路识别模型在煤矿场景中因目标尺度变化复杂导致识别准确率低、参数量大难以满足巡检机器人部署需求、对掉落管路无法准确判别的问题,提出了一种基于改进YOLOv8n的煤矿巷道异常管路智能识别方法。在YOLOv8n模型基础上引入... 针对现有异常管路识别模型在煤矿场景中因目标尺度变化复杂导致识别准确率低、参数量大难以满足巡检机器人部署需求、对掉落管路无法准确判别的问题,提出了一种基于改进YOLOv8n的煤矿巷道异常管路智能识别方法。在YOLOv8n模型基础上引入MobileNetV4改进主干网络,以降低参数量并提升特征提取效率;引入倒置残差高效多尺度注意力(iEMA)机制,以增强多尺度目标特征捕获能力;在颈部网络采用全维动态卷积(ODConv)替换标准卷积,以提升局部细粒度特征融合与识别精度;引入Focal-EIoU损失函数,以改善小尺度漏水目标与细长管路样本不均衡问题,提升模型边界框回归质量。针对管路掉落识别,提出了基于管路锚框与地面锚框重合度、管路倾斜角度的双指标判别方法:当管路锚框与地面锚框重合,判定管路坠地;否则判定管路未坠地,并判断管路倾斜角度是否大于设定阈值,若是则判定管路垂落。实验结果表明:与YOLOv8n模型相比,改进YOLOv8n模型在参数量降低19%的前提下,准确率、召回率、m AP@0.5分别提升了3.3%,4.7%,3.9%;改进YOLOv8n模型实现了检测精度与速度的平衡,且在小尺度漏水目标与掉落管路识别中未发生漏检;改进YOLOv8n模型在边缘设备部署后,能准确识别异常管路,平均检测时间为9.1 ms,内存占用仅为98 MiB,满足巡检机器人对异常管路实时、准确识别的需求。 展开更多
关键词 异常管路识别 管路漏水识别 管路掉落识别 改进YOLOv8n MobilenetV4 iEMA ODConv
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Estrogen affects neuropathic pain through upregulating N-methyl-D-aspartate acid receptor 1 expression in the dorsal root ganglion of rats 被引量:8
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作者 Chao Deng Ya-juan Gu +1 位作者 Hong Zhang Jun Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第3期464-469,共6页
Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1(NMDAR1) plays an important role in t... Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1(NMDAR1) plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D(-)-2-amino-5-phosphonopentanoic acid(AP-5),or both once daily for 15 days.Compared with injured drug na?ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity(as assessed by immunohistochemistry) and protein(as determined by western blot assay) in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia. 展开更多
关键词 nerve regeneration peripheral nerve injury ESTROGEn 17Β-ESTRADIOL n-rnethyl-D-aspartic acid receptor 1 pain sciatic nerve chronic constriction injury neuropathic pain D(-)-2-amino-5-phosphonopentanoic acid dorsal root ganglion spinal cord IMMUnOREACTIVITY western blot assay neural regeneration
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Exploring the effect of aggregation-induced emission on the excited state intramolecular proton transfer for a bis-imine derivative by quantum mechanics and our own n-layered integrated molecular orbital and molecular mechanics calculations
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作者 Huifang Zhao Chaofan Sun +2 位作者 Xiaochun Liu Hang Yin Ying Shi 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期645-649,共5页
We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonometh... We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonomethyl)-naphthalene-2-ol and 1-pyrenecarboxaldehyde. Especially, the density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods for HNP monomer are introduced. Moreover, the "our own n-layered integrated molecular orbital and molecular mechanics"(ONIOM) method(TDDFT:universal force field(UFF)) is used to reveal the aggregation-induced emission(AIE) effect on the ESIPT process for HNP in crystal. Our results confirm that the ESIPT process happens upon the photoexcitation for the HNP monomer and HNP in crystal, which is distinctly monitored by the optimized geometric structures and the potential energy curves. In addition, the results of potential energy curves reveal that the ESIPT process in HNP will be promoted by the AIE effect. Furthermore, the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) for the HNP monomer and HNP in crystal have been calculated. The calculation demonstrates that the electron density decrease of proton donor caused by excitation promotes the ESIPT process. In addition, we find that the variation of atomic dipole moment corrected Hirshfeld population(ADCH) charge for proton acceptor induced by the AIE effect facilitates the ESIPT process. The results will be expected to deepen the understanding of ESIPT dynamics for luminophore under the AIE effect and provide insight into future design of high-efficient AIE compounds. 展开更多
关键词 time-dependent density functional theory(TDDFT) METHOD excited state intramolecular proton transfer(ESIPT) our own n-layered integrated MOLECULAR orbital and MOLECULAR mechanics(OnIOM) METHOD potential energy curves atomic dipole moment corrected Hirshfeld population(ADCH) charge
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Relationship between high dietary fat intake and Parkinson’s disease risk: a meta-analysis 被引量:3
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作者 Yan Qu Xi Chen +1 位作者 Man-Man Xu Qiang Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第12期2156-2163,共8页
OBJECTIVE: To assess whether dietary fat intake influences Parkinson’s disease risk. DATA SOURCES: We systematically surveyed the Embase and PubMed databases, reviewing manuscripts published prior to October 2018. Th... OBJECTIVE: To assess whether dietary fat intake influences Parkinson’s disease risk. DATA SOURCES: We systematically surveyed the Embase and PubMed databases, reviewing manuscripts published prior to October 2018. The following terms were used:(“Paralysis agitans” OR “Parkinson disease” OR “Parkinson” OR “Parkinson’s” OR “Parkinson’s disease”) AND (“fat” OR “dietary fat” OR “dietary fat intake”). DATA SELECTION: Included studies were those with both dietary fat intake and Parkinson’s disease risk as exposure factors. The Newcastle-Ottawa Scale was adapted to investigate the quality of included studies. Stata V12.0 software was used for statistical analysis. OUTCOME MEASURES: The primary outcomes included the relationship between high total energy intake, high total fat intake, and Parkinson’s disease risk. The secondary outcomes included the relationship between different kinds of fatty acids and Parkinson’s disease risk. RESULTS: Nine articles met the inclusion criteria and were incorporated into this meta-analysis. Four studies scored 7 and the other five studies scored 9 on the Newcastle-Ottawa Scale, meaning that all studies were of high quality. Meta-analysis results showed that high total energy intake was associated with an increased risk of Parkinson’s disease (P = 0.000, odds ratio (OR)= 1.49, 95% confidence interval (CI): 1.26–1.75);in contrast, high total fat intake was not associated with Parkinson’s disease risk (P = 0.123, OR = 1.07, 95% CI: 0.91–1.25). Subgroup analysis revealed that polyunsaturated fatty acid intake (P = 0.010, OR = 1.03, 95% CI: 0.88–1.20) reduced the risk of Parkinson’s disease, while arachidonic acid (P = 0.026, OR = 1.15, 95% CI: 0.97–1.37) and cholesterol (P = 0.002, OR = 1.09, 95% CI: 0.92–1.29) both increased the risk of Parkinson’s disease. Subgroup analysis also demonstrated that, although the results were not significant, consumption of n-3 polyunsaturated fatty acids (P = 0.071, OR = 0.88, 95% CI: 0.73–1.05),α-linolenic acid (P = 0.06, OR = 0.86, 95% CI: 0.72–1.02), and the n-3 to n-6 ratio (P = 0.458, OR = 0.89, 95% CI: 0.75–1.06) were all linked with a trend toward reduced Parkinson’s disease risk. Monounsaturated fatty acid (P = 0.450, OR = 1.06, 95% CI: 0.91–1.23), n-6 polyunsaturated fatty acids (P = 0.100, OR = 1.15, 95% CI: 0.96–1.36) and linoleic acid (P = 0.053, OR = 1.11, 95% CI: 0.94–1.32) intakes were associated with a non-significant trend toward higher PD risk. Saturated fatty acid (P = 0.619, OR = 1.01, 95% CI: 0.87–1.18) intake was not associated with Parkinson’s disease. CONCLUSION: Dietary fat intake affects Parkinson’s disease risk, although this depends on the fatty acid subtype. Higher intake of polyunsaturated fatty acids may reduce the risk of Parkinson’s disease, while higher cholesterol and arachidonic acid intakes may elevate Parkinson’s disease risk. However, further studies and evidence are needed to validate any link between dietary fat intake and Parkinson’s disease. 展开更多
关键词 nerve REGEnERATIOn dietary fat Parkinson's disease risk META-AnALYSIS total energy InTAKE polyunsaturated FATTY ACIDS arachidonic ACID cholesterol α-linolenic ACID linoleic ACID n-3/n-6 polyunsaturated FATTY ACID InTAKE ratio monounsaturated FATTY ACIDS neural REGEnERATIOn
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Methods of cumulative quantum mechanics for describing the interaction of electromagnetic fields with matter in Vysikaylo large standing nanoscale excitons:Hydrogen-like atoms,molecules,surfaces,and twinkling crystals
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作者 Philipp I.Vysikaylo 《Nanotechnology and Precision Engineering》 2025年第4期127-142,共16页
Using cumulative quantum mechanics(CQM)and the method of generalized mathematical transfer(MGMT),we analytically study quantum nanometer cumulative-dissipative structures(CDS)and the forces arising within them,which f... Using cumulative quantum mechanics(CQM)and the method of generalized mathematical transfer(MGMT),we analytically study quantum nanometer cumulative-dissipative structures(CDS)and the forces arising within them,which focus nanostructures into regular,fractalized systems—cumulative-dissipative standing hydrogen-like excitons(atoms,molecules,lines,surfaces)and flickering crystals we discovered for the first time.(1)We demonstrate the formation of Vysikaylo standing excitons on permittivity[ε(r)]inhomogeneities in diamond in the nanoscale regions of foreign atoms.(2)For the first time,we solve the problem of measuringε(r)profiles in inhomogeneous nanoscale structures using Raman spectra(RS)[with an accuracy of up to 99.9%forε(r)and a step of up to 0.3 nm depending on the distance from the impurity atom(boron)].(3)Using our theory of Vysikaylo standing excitons,we explain the experimental observation of the degeneracy of electron spectra in standing excitons with respect to the principal quantum number n and n−1/2.By comparing the theory and experimental observations of RS in diamonds doped with boron,we solve the problem(that we formulated previously)between the de Broglie hypothesis and the classical new quantum mechanics of Dirac(which limits the-functions,or prohibits symmetric de Broglie half-waves in spherically and cylindrically symmetric quantum resonators)in favor of the de Broglie hypothesis.Based on the works of Wannier and Mott,we refine the definition of the permittivity of nanocrystals as a coefficient in electric potentials[U(r)→ε(r)U(r)]rather than electric fields[D(r)=ε(r)E(r)].We construct the most complete theory of the chemical doping of crystals(using the example of group IV crystals doped with group III and V atoms).For the first time,we raise the question of the quantum cleaning of crystals or the accumulation of dopant atoms. 展开更多
关键词 Physical and chemical doping of nanostructured materials Vysikaylo cumulative-dissipative structures Flickering hyperatoms MOLECULES and crystal lattices Cumulative quantum mechanics Cumulation of de Broglie waves Unlimited cumulation of de Broglie waveψ_(n−1/2)-functions Points lines planes of cumulation-libration
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