期刊文献+
共找到8,643篇文章
< 1 2 250 >
每页显示 20 50 100
Conformational dynamics as an intrinsic determinant of prion protein misfolding and neurotoxicity
1
作者 Alessandro Cembran Pedro Fernandez-Funez 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2095-2096,共2页
The prion protein(PrP) is the key molecular and pathological mediator of prion diseases,a heterogeneous group of brain disorders with fatal outcomes.Prion diseases are rare but deserve special attention because of the... The prion protein(PrP) is the key molecular and pathological mediator of prion diseases,a heterogeneous group of brain disorders with fatal outcomes.Prion diseases are rare but deserve special attention because of their unique familial,sporadic,and transmissible etiologies,all caused by a single agent:misfolded conformations of PrP. 展开更多
关键词 FOLDING intrinsic DYNAMICS
下载PDF
Intrinsic and scattering attenuations of the Sichuan-Yunnan region in China from S coda waves
2
作者 Tian Li Lei Zhang +4 位作者 Xiaodong Song Qincai Wang Xinyu Jiang Jinchuan Zhang Hanlin Chen 《Earthquake Science》 2024年第1期51-66,共16页
Seismic attenuation is a fundamental property of the Earth's media.Attenuation structure for the complicated geological structures with strong seismicity in the Sichuan-Yunnan region is poorly studied.In this stud... Seismic attenuation is a fundamental property of the Earth's media.Attenuation structure for the complicated geological structures with strong seismicity in the Sichuan-Yunnan region is poorly studied.In this study,we collected 108,399 waveforms of 11,517 local small earthquakes with magnitudes between 1.5 and 3.5 from January 2014 to September 2021 in the Sichuan-Yunnan region and its adjacent areas.We employed an envelope inversion technique for separating the intrinsic and scattering attenuations of the S coda wave,and obtained the intrinsic and scattering attenuation structures for frequencies between 0.25 and 8.00 Hz.The attenuation structures correlate well with the geological units,and some major faults mark the attenuation variations where historic large earthquakes have occurred.The regional average attenuation shows a negative frequency dependence.The average scattering attenuation has a faster descending rate than the average intrinsic attenuation,and is dominant at low frequencies,while at high frequencies the average intrinsic attenuation is stronger.The lateral variation in the intrinsic attenuation is consistent with the variation in heat flow,the scattering attenuation may be related to the scatter distribution and size.The total attenuation is consistent with the previous studies in this region,and the separate intrinsic and scattering attenuation may be useful in understanding regional tectonics and important in earthquake prevention and disaster reduction. 展开更多
关键词 intrinsic attenuation scattering attenuation Sichuan-Yunnan region
下载PDF
Linearization of Intrinsically Nonlinear Oscillators
3
作者 Pirooz Mohazzabi Qinghua Luo Ilirian Dhimitruka 《Journal of Applied Mathematics and Physics》 2024年第8期2829-2835,共7页
We show that an intrinsically nonlinear oscillator can always be transformed into a linear or harmonic oscillator by addition of a constant force, which shifts the equilibrium position of the oscillator.
关键词 intrinsic NONLINEAR OSCILLATOR LINEARIZATION
下载PDF
Experimental Study of the Influence of Intrinsic Parameters on the Thermal Reactivity of Sawdust, Polyethylene Terephthalate and Composite
4
作者 Ange Brel Boukongou Timoléon Andzi Barhé 《Journal of Materials Science and Chemical Engineering》 2024年第3期9-20,共12页
Several works have been based on the study of thermal variations in biomass to derive more valuable products such as fuels capable of replacing oil in the event of a crisis or activated carbon used as an adsorbent mat... Several works have been based on the study of thermal variations in biomass to derive more valuable products such as fuels capable of replacing oil in the event of a crisis or activated carbon used as an adsorbent material, widely used in industry for the elimination of unwanted materials, both in liquid and gaseous environments. A study of thermal parameters such as: heating speed, retention time, drying temperature, carbonization temperature, particle size, was carried out with the aim of determining the characteristic factors of the carbonization of Polyethylene terephthalate (PET), sawdust (SC) and sawdust/polyethylene terephthalate (CPS) mixture. The results of the immediate analysis revealed a very low level of ash in PET (0.013%) compared to the level of ash in sawdust (2.9%), as well as a high level of fixed carbon (82.960%), which suggests the presence of mineral oxides and a significant carbon matrix unlike PET, which indicates a very significant organic matrix (essentially made up of organic matter) with the absence of mineral oxides. The study of thermal parameters showed the water loss from Sawdust (SC) and the Sawdust/Polyethylene terephthalate (CPS) mixture, an increase with temperature, unlike that of PET whose variation is essentially zero. Without heat treatment, sawdust alone contains approximately 7% water. The optimal drying temperature for this study is 110˚C for a stay of 24 hours. It appears that the largest mass losses for the PET samples are between 87.19% and 96.05%, followed by that of the mixture, between 47.33% and 64.37%. And the lowest are observed, those of sawdust (from 24.02% to 62.6%). However, here we can say that the influence of the mass is not great, given the slight difference between the losses by temperature. The results of the study of the influence of grain size showed that the differences are insignificant, even if we vary the diameter of the grains from simple to triple. To better minimize physical constraints such as the intragranular diffusibility of the volatile matter and the homogeneity of the temperature in the grains, 75 μm particles are found to be optimal for our study. It can be noted when studying the heating rate that the mass loss at the end of the reaction is approximately the same depending on each precursor material. However, it has been demonstrated that the heating rate strongly influences the nature of the reaction products both for volatile materials and for the solid residue as well as on the kinetic parameters of the chemical reaction. Furthermore, the variation in apparent density shows a decrease as a function of the increase in the residence time of the materials in the reactor. As the carbonization time increases, the apparent density decreases. We note, for the lignocellulosic material, that the apparent density stabilizes after 60 minutes. 展开更多
关键词 intrinsic Parameters Thermal Reactivity SAWDUST Polyethylene Terephthalate COMPOSITE
下载PDF
A novel DPSS filter optimization scheme to reduce the intrinsic interference of FBMC-QAM systems
5
作者 董琪阳 MA Tianming +1 位作者 JIN Jie WU Zhong 《High Technology Letters》 EI CAS 2024年第1期68-74,共7页
In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is p... In order to reduce the intrinsic interference of the filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM)system,a novel filter optimization scheme based on discrete prolate spheroidal sequences(DPSS)is proposed.Firstly,a prototype filter function based on DPSS is designed,since the eigenvalue can be used as an indicator of the energy concentration of DPSS,so a threshold is set,and the sequence with the most concentrated energy is selected under the threshold,that is,the sequence with the eigenvalue higher than the threshold,and the prototype filter function is rewritten as a weighted sum function of multiple eigenvectors.Under the energy constraints of the filter,the relationship between the eigenvectors and the intrinsic interference function is established,and the function problem is transformed into an optimization problem for the weighted coefficients.Through the interior point method,the most suitable weight is found to obtain the minimum intrinsic interference result.Theoretical analysis and simulation results show that compared with the prototype filters such as Type1 and CaseC,the DPSS filter applying the proposed optimization algorithm can effectively suppress the intrinsic interference of the system and obtain a better bit error rate(BER)performance. 展开更多
关键词 filter bank multicarrier-quadrature amplitude modulation(FBMC-QAM) intrinsic interference discrete prolate spheroidal sequences(DPSS) interior point method
下载PDF
Intrinsic Spin Angular Momentum of Electron Relation to the Discrete Indivisible Quantum of Time Kshana or Moment
6
作者 Shesharao M. Wanjerkhede 《Journal of Modern Physics》 2024年第9期1337-1352,共16页
The frequency of any periodic event can be defined in terms of units of Time. Planck constructed a unit of time called the Plank time from other physical constants. Vyasa defined a natural unit of time, kshana, or mom... The frequency of any periodic event can be defined in terms of units of Time. Planck constructed a unit of time called the Plank time from other physical constants. Vyasa defined a natural unit of time, kshana, or moment based on the motion of a fundamental particle. It is the time taken by an elementary particle, to change its direction from east to north. According to Vyasa, kshana is discrete, exceedingly small, indivisible, and is a constant time quantum. When the intrinsic spin angular momentum of an electron was related to the angular momentum of a simple thin circular plate, spherical shell, and solid sphere model of an electron, we found that the value of kshana in seconds was equal to ten to a power of minus twenty-one second. The disc model for the spinning electron provides an accurate value of the number of kshanas per second as determined previously and compared with other spinning models of electrons. These results indicate that the disk-like model of spinning electrons is the correct model for electrons. Vyasa’s definition of kshana opens the possibility of a new foundation for the theory of physical time, and perspectives in theoretical and philosophical research. 展开更多
关键词 Natural Time Unit Quantum Time Kshana Plank Time intrinsic Angular Momentum Thin Disc Model Compton Wavelength
下载PDF
Extrinsic and intrinsic mechanisms of axon regeneration:the need for spinal cord injury treatment strategies to address both 被引量:5
7
作者 Christina Francisca Vogelaar 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第4期572-574,共3页
Spinal cord injury(SCI)causes disturbances in motor and sensory functions leading to paralysis,the severity of which depends on the spinal level of the injury.Traumatic lesions of spinal cord axon projection tracts ... Spinal cord injury(SCI)causes disturbances in motor and sensory functions leading to paralysis,the severity of which depends on the spinal level of the injury.Traumatic lesions of spinal cord axon projection tracts are untreatable in human patients,although numerous research groupsworldwide are studying putative treatment strategies. 展开更多
关键词 GENE extrinsic and intrinsic mechanisms of axon regeneration
下载PDF
Characteristics of anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic,extrinsic,and external electric-field induced spin-orbit couplings 被引量:1
8
作者 Liu Song Yan Yu-Zhen Hu Liang-Bin 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期469-476,共8页
The various competing contributions to the anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic, extrinsic and external electric-field induced spin-orbit coupling we... The various competing contributions to the anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic, extrinsic and external electric-field induced spin-orbit coupling were investigated theoretically. Based on a unified semiclassical theoretical approach, it is shown that the total anomalous Hall conductivity can be expressed as the sum of three distinct contributions in the presence of these competing spin-orbit interactions, namely an intrinsic contribution determined by the Berry curvature in the momentum space, an extrinsic contribution determined by the modified Bloch band group velocity and an extrinsic contribution determined by spin-orbit-dependent impurity scattering. The characteristics of these competing contributions are discussed in detail in the paper. 展开更多
关键词 anomalous Hall effect intrinsic spin orbit coupling extrinsic spin orbit coupling exter- nal electric-field induced spin-orbit coupling
下载PDF
Gatifloxacin inducing apoptosis of stromal fibroblasts through cross-talk between caspase-dependent extrinsic and intrinsic pathways
9
作者 Bin Xu Yun-Long Sui Ting-Jun Fan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第10期1524-1530,共7页
AIM: To reveal the cytotoxicity and related mechanisms of gatifloxacin(GFX) to stromal fibroblasts(SFs) in vitro.METHODS: SFs were treated with GFX at different concentrations(0.009375%-0.3%), and their viability was ... AIM: To reveal the cytotoxicity and related mechanisms of gatifloxacin(GFX) to stromal fibroblasts(SFs) in vitro.METHODS: SFs were treated with GFX at different concentrations(0.009375%-0.3%), and their viability was detected by MTT method. The cell morphology was observed using light/transmission electron microscope. The plasma membrane permeability was measured by AO/EB double-staining. Then cell cycle, phosphatidylserine(PS) externalization, and mitochondrial transmembrane potential(MTP) were analyzed by flow cytometry. DNA damage was analyzed by electrophoresis and immunostaining. ELISA was used to evaluate the caspase-3/-8/-9 activation. Finally, Western blotting was applied for detecting the expressions of apoptosis-related proteins.RESULTS: Morphological changes and reduced viability of GFX-treated SFs demonstrated that GFX above 0.009375% had cytotoxicity to SFs with dependence of concentration and time. GFX-treating cells also showed G1 phase arrest, increased membrane permeability, PS externalization and DNA damage, which indicated that GFX induced apoptosis of SFs. Additionally, GFX could activate the caspase-8, caspase-9, and caspase-3, induce MTP disruption, downregulate B-cell leukemia-2(Bcl-2) and B-cell leukemiaXL(Bcl-XL), and upregulate Bcl-2 assaciated X protein(Bax), Bcl-2-associated death promoter(Bad), Bcl-2 interacting domain(Bid) and cytoplasmic cytochrome C in SFs, suggesting that caspase-dependent extrinsic and intrinsic pathways were related to GFX-contributed apoptosis of SFs.CONCLUSION: The cytotoxicity of GFX induces apoptosis of SFs through triggering the caspase-dependent extrinsic and intrinsic pathways. 展开更多
关键词 GATIFLOXACIN STROMAL FIBROBLASTS cytotoxicity apoptosis CASPASE extrinsic PATHWAY intrinsic PATHWAY
下载PDF
Robust visual tracking for manipulators withunknown intrinsic and extrinsic parameters
10
作者 Chaoli WANG Xueming DING 《控制理论与应用(英文版)》 EI 2007年第4期420-426,共7页
This paper addresses the robust visual tracking of multi-feature points for a 3D manipulator with unknown intrinsic and extrinsic parameters of the vision system. This class of control systems are highly nonlinear con... This paper addresses the robust visual tracking of multi-feature points for a 3D manipulator with unknown intrinsic and extrinsic parameters of the vision system. This class of control systems are highly nonlinear control systems characterized as time-varying and strong coupling in states and unknown parameters. It is first pointed out that not only is the Jacobian image matrix nonsingular, but also its minimum singular value has a positive limit. This provides the foundation of kinematics and dynamics control of manipulators with visual feedback. Second, the Euler angle expressed rotation transformation is employed to estimate a subspace of the parameter space of the vision system. Based on the two results above, and arbitrarily chosen parameters in this subspace, the tracking controllers are proposed so that the image errors can be made as small as desired so long as the control gain is allowed to be large. The controller does not use visual velocity to achieve high and robust performance with low sampling rate of the vision system. The obtained results are proved by Lyapunov direct method. Experiments are included to demonstrate the effectiveness of the proposed controller. 展开更多
关键词 ROBUST Visual tracking MANIPULATOR CAMERA intrinsic and extrinsic parameters
下载PDF
Intrinsic and Extrinsic Automatic Evaluation Strategies for Paraphrase Generation Systems
11
作者 Tulu Tilahun Hailu Junqing Yu Tessfu Geteye Fantaye 《Journal of Computer and Communications》 2020年第2期1-16,共16页
Paraphrase is an expression of a text with alternative words and orders to achieve a better clarity. Paraphrases have been found vital for augmenting training dataset, which aid to enhance performance of machine learn... Paraphrase is an expression of a text with alternative words and orders to achieve a better clarity. Paraphrases have been found vital for augmenting training dataset, which aid to enhance performance of machine learning models that intended for various natural language processing (NLP) tasks. Thus, recently, automatic paraphrase generation has received increasing attention. However, evaluating quality of generated paraphrases is technically challenging. In the literature, the importance of generated paraphrases is tended to be determined by their impact on the performance of other NLP tasks. This kind of evaluation is referred as extrinsic evaluation, which requires high computational resources to train and test the models. So far, very little attention has been paid to the role of intrinsic evaluation in which quality of generated paraphrase is judged against predefined ground truth (reference paraphrases). In fact, it is also very challenging to find ideal and complete reference paraphrases. Therefore, in this study, we propose semantic or meaning oriented automatic evaluation metric that helps to evaluate quality of generated paraphrases against the original text, which is an intrinsic evaluation approach. Further, we evaluate quality of the paraphrases by assessing their impact on other NLP tasks, which is an extrinsic evaluation method. The goal is to explore the relationship between intrinsic and extrinsic evaluation methods. To ensure the effectiveness of proposed evaluation methods, extensive experiments are done on different publicly available datasets. The experimental results demonstrate that our proposed intrinsic and extrinsic evaluation strategies are promising. The results further reveal that there is a significant correlation between intrinsic and extrinsic evaluation approaches. 展开更多
关键词 PARAPHRASE PARAPHRASE Generation Natural Language Processing intrinsic extrinsic Automatic Evaluation Word Embedding SENTIMENT Analysis
下载PDF
Manipulating extrinsic and intrinsic obstacles to axonal regeneration after spinal cord injury
12
作者 Eugene Mironets Di Wu Veronica J.Tom 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第2期224-225,共2页
Spinal cord injury(SCI)is a traumatic event that can lead to permanent motor and sensory deficits.After the initial trauma,axons of surviving neurons rapidly retract.While there may be a small degree of abortive spr... Spinal cord injury(SCI)is a traumatic event that can lead to permanent motor and sensory deficits.After the initial trauma,axons of surviving neurons rapidly retract.While there may be a small degree of abortive sprouting,virtually all attempts at robust regrowth across the lesion site ultimately fail.Thus,neurons below the level of the injury are permanently disconnected from their normal input,resulting in persistent loss of function. 展开更多
关键词 RHEB Manipulating extrinsic and intrinsic obstacles to axonal regeneration after spinal cord injury
下载PDF
Generational Gap: Intrinsic (Non-monetary) Versus Extrinsic (Monetary) Rewards in the Workforce
13
作者 Charles Chekwa Mmutakaego Chukwuanu Daisey Richardson 《Chinese Business Review》 2013年第6期414-424,共11页
Traditionally, organizations assume that compensation/pay and monetary benefits are what all employees need to work harder, be productive, or remain with the company. According to Abraham Maslow, within every person i... Traditionally, organizations assume that compensation/pay and monetary benefits are what all employees need to work harder, be productive, or remain with the company. According to Abraham Maslow, within every person is a hierarchy of five needs: physiological needs, safety needs, social needs, esteem needs, and self-actualization needs Organizations must be able to identify what employees desire to secure optimum performance and to meet the needs of both employees and employers. This research focuses on the generational gap and the significance of intrinsic and extrinsic rewards in the workforce. The purpose and objective of this research are to test the significance of monetary versus non-monetary rewards among the different generations in the organization. A self-designed questionnaire distributed to a multi-generational group of employees of selected organizations was used to collect the analyzed data. Sixty-five (65%) responses were obtained. Secondary data were used to elucidate the needs in this area of study. Because the workforce is predicted to become more diverse in terms of age, organizations will be unlikely to implement one set of rewards for the multiple generations. This is due to the differing expectations and requirements among the generations. However, the results indicate no significant difference in monetary versus non-monetary rewards among the different generations in the workforce. 展开更多
关键词 monetary benefits intrinsic reward extrinsic reward MOTIVATION multi-generational workforce monetary and non-monetary rewards
下载PDF
Intrinsic Self-Healing Chemistry for Next-Generation Flexible Energy Storage Devices 被引量:7
14
作者 Xin Wan Tiansheng Mu Geping Yin 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第7期136-164,共29页
The booming wearable/portable electronic devices industry has stimulated the progress of supporting flexible energy storage devices.Excellent performance of flexible devices not only requires the component units of ea... The booming wearable/portable electronic devices industry has stimulated the progress of supporting flexible energy storage devices.Excellent performance of flexible devices not only requires the component units of each device to maintain the original performance under external forces,but also demands the overall device to be flexible in response to external fields.However,flexible energy storage devices inevitably occur mechanical damages(extrusion,impact,vibration)/electrical damages(overcharge,over-discharge,external short circuit)during longterm complex deformation conditions,causing serious performance degradation and safety risks.Inspired by the healing phenomenon of nature,endowing energy storage devices with self-healing capability has become a promising strategy to effectively improve the durability and functionality of devices.Herein,this review systematically summarizes the latest progress in intrinsic self-healing chemistry for energy storage devices.Firstly,the main intrinsic self-healing mechanism is introduced.Then,the research situation of electrodes,electrolytes,artificial interface layers and integrated devices based on intrinsic self-healing and advanced characterization technology is reviewed.Finally,the current challenges and perspective are provided.We believe this critical review will contribute to the development of intrinsic self-healing chemistry in the flexible energy storage field. 展开更多
关键词 Flexible energy storage intrinsic self-healing chemistry Lithium-ion battery Supercapacitor Advanced characterizations
下载PDF
How to make the "jump" on understanding the importance of the intrinsic foot muscles for propulsion
15
作者 Michael J.Asmussen 《Journal of Sport and Health Science》 SCIE CAS CSCD 2023年第5期648-650,共3页
In this issue of the Journal of Sport and Health Science,Smith and colleagues1addressed a unique aspect of human locomotion;they evaluated the effects of the intrinsic foot musculature on the mechanical properties and... In this issue of the Journal of Sport and Health Science,Smith and colleagues1addressed a unique aspect of human locomotion;they evaluated the effects of the intrinsic foot musculature on the mechanical properties and energetic function of the human foot.By performing a controlled jumping experiment to mimic components of human locomotion. 展开更多
关键词 intrinsic muscles PROPULSION
下载PDF
Single-Molecule Confinement Induced Intrinsic Multi-Electron Redox-Activity to Enhance Supercapacitor Performance
16
作者 Su Yang Meiling Wang +8 位作者 Yong Zhang Pinyi He Wenhua Cong Chongji Wang Qiankun Yang Xuguang Liu Tian Wang Xianming Zhang Jiadong Zhou 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期227-238,共12页
Aggregation of polyoxometalates(POM)is largely responsible for the reduced performance of POM-based energy-storage systems.To address this challenge,here,the precise confinement of single Keggin-type POM molecule in a... Aggregation of polyoxometalates(POM)is largely responsible for the reduced performance of POM-based energy-storage systems.To address this challenge,here,the precise confinement of single Keggin-type POM molecule in a porous carbon(PC)of unimodal super-micropore(micro-PC)is realized.Such precise single-molecule confinement enables sufficient activity center exposure and maximum electron-transfer from micro-PC to POM,which well stabilizes the electron-accepting molecules and thoroughly activates its inherent multi-electron redox-activity.In particular,the redox-activities and electron-accepting properties of the confined POM molecule are revealed to be super-micropore pore size-dependent by experiment and spectroscopy as well as theoretical calculation.Meanwhile,the molecularly dispersed POM molecules confined steadily in the“cage”of micro-PC exhibit unprecedented large-negative-potential stability and multiple-peak redox-activity at an ultra-low loading of~11.4 wt%.As a result,the fabricated solid-state supercapacitor achieves a remarkable areal capacitance,ultrahigh energy and power density of 443 mF cm^(-2),0.12 mWh cm^(-2)and 21.1 mW cm^(-2),respectively.This work establishes a novel strategy for the precise confinement of single POM molecule,providing a versatile approach to inducing the intrinsic activity of POMs for advanced energy-storage systems. 展开更多
关键词 intrinsic redox-activity POLYOXOMETALATES single-molecule confinement SUPERCAPACITOR
下载PDF
Single-layer intrinsic 2H-phase LuX_(2)(X=Cl,Br,I)with large valley polarization and anomalous valley Hall effect
17
作者 胡春生 仵允京 +4 位作者 刘元硕 傅帅 崔晓宁 王易昊 张昌文 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期478-483,共6页
Manipulation of the valley degree of freedom provides a new path for quantum information technology,but the real intrinsic large valley-polarization materials are rarely reported up to date.Here,we perform first-princ... Manipulation of the valley degree of freedom provides a new path for quantum information technology,but the real intrinsic large valley-polarization materials are rarely reported up to date.Here,we perform first-principles calculations to predict a class of 2H-phase single layer(SL)materials LuX_(2)(X=Cl,Br,I)to be ideal candidates.SL-Lu X_(2)are ferrovalley materials with a giant valley-polarization of 55 meV–148 meV as a result of its large spin–orbital coupling(SOC)and intrinsic ferromagnetism(FM).The magnetic transition temperatures of SL-LuI_(2)and SL-LuCl2are estimated to be 89 K–124 K,with a sizable magnetic anisotropy at out-of-plane direction.Remarkably,the anomalous valley Hall effect(AVHE)can be controlled in SL-LuX_(2)when an external electric field is applied.Moreover,the intrinsic valleypolarization of SL-LuI_(2)is highly robust for biaxial strain.These findings provide a promising ferrovalley material system for the experimentation of valleytronics and subsequent applications. 展开更多
关键词 intrinsic ferrovalley anomalous valley Hall effect first-principles calculations
下载PDF
Intrinsic kinetics of catalytic hydrogenation of 2-nitro-4-acetylamino anisole to 2-amino-4-acetylamino anisole over Raney nickel catalyst
18
作者 Xiangyang Cui Xin Zhang +5 位作者 Baoju Wang Yuqi Sun Haikui Zou Guangwen Chu Yong Luo Jianfeng Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期1-8,共8页
The catalytic hydrogenation of 2-nitro-4-acetylamino anisole(NMA)is a less-polluting and efficient method to produce 2-amino-4-acetamino anisole(AMA).However,the kinetics of catalytic hydrogenation of NMA to AMA remai... The catalytic hydrogenation of 2-nitro-4-acetylamino anisole(NMA)is a less-polluting and efficient method to produce 2-amino-4-acetamino anisole(AMA).However,the kinetics of catalytic hydrogenation of NMA to AMA remains obscure.In this work,the kinetic models including power-law model and Langmuir-Hinshelwood-Hougen-Watson(LHHW)model of NMA hydrogenation to AMA catalyzed by Raney nickel catalyst were investigated.All experiments were carried out under the elimination of mass transfer resistance within the temperature range of 70–100°C and the hydrogen pressure of 0.8–1.5 MPa.The reaction was found to follow 0.52-order kinetics with respect to the NMA concentration and 1.10-order kinetics in terms of hydrogen pressure.Based on the LHHW model,the dual-site dissociation adsorption of hydrogen was analyzed to be the rate determining step.The research of intrinsic kinetics of NMA to AMA provides the guidance for the reactor design and inspires the catalyst modification. 展开更多
关键词 intrinsic kinetics 2-nitro-4-acetylamino anisole Catalytic hydrogenation Raney nickel catalyst
下载PDF
The Inner Structure of the Intrinsic Electron and the Origin of Self-Mass
19
作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期174-189,共16页
A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynami... A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynamics has been underutilized in particle physics. Such observation leads to discovery of a principal component in the electron inner structure—the charged c-ring. The intrinsic (fundamental) electron model based on the charged c-ring successfully explains the ontology of the charge fractionation in quantum chromodynamics and the formation of Cooper pairs in superconductivity. The c-ring properties are explained on the basis of the General Compton Conditions as defined. Properties of the charged c-ring include the explanation of the boundary conditions, electro-magnetostatic field configuration, self-mass, spin, magnetic moment, and the gyromagnetic ratio. The self-mass of the intrinsic electron is 100% electro-magnetostatic and it is shown how to compute its value. The classical-quantum divide no longer exists. Relation between the intrinsic electron and the electron is fundamentally defined. The electron is the composite fermion consisting of the intrinsic electron and the neutrino. The ontology of the anomaly in the electron magnetic moment is demonstrated—it is due to the addition of the neutrino magnetic moment to the overall electron magnetic moment. The intrinsic electron replaces the W? boson in particle physics, resulting in a fundamental implication for the Standard Model. 展开更多
关键词 intrinsic Electron Inner Structure Electro-Magnetostatic Self-Mass General Compton Conditions Charged C-Ring Visualization C-Ring Length Constant
下载PDF
Design of novel transition-metal-doped C_(4)N_(4) as highly effective electrocatalysts for nitrogen fixation with a new intrinsic descriptor
20
作者 Cheng He Jianglong Ma +1 位作者 Yibo Wu Wenxue Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期131-139,共9页
Electrocatalytic nitrogen reduction reaction(NRR) is an efficient and green way to produce ammonia,which offers an alternative option to the conventional Haber-Bosch process.Unfortunately,the large-scale industrial ap... Electrocatalytic nitrogen reduction reaction(NRR) is an efficient and green way to produce ammonia,which offers an alternative option to the conventional Haber-Bosch process.Unfortunately,the large-scale industrial application of NRR processes is still hindered by poor Faraday efficiency and high overpotential,which need to be overcome urgently.Herein,combined with density functional theory and particle swarm optimization algorithm for the nitrogen carbide monolayer structural search(C_mN_(8-m),m=1-7),the surprising discovery is that single transition metal-atom-doped C_(4)N_(4) monolayers(TM@C_(4)N_(4)) could effectively accelerate nitrogen reduction reaction.TM@C_(4)N_(4)(TM=29 transition metals) as single-atom catalysts are evaluated via traditional multi-step screening method,and their structures,NRR activity,selectivity and solvation effect are investigated to evaluate their NRR performance,Through the screening steps,W@C_(4)N_(4) possesses the highest activity for NRR with a very low limiting potential of-0.29 V.Moreover,an intrinsic descriptor φ is proposed with machine learning,which shortens the screening process and provides a new idea for finding efficient SACs.This work not only offers promising catalysts W@C_(4)N_(4) for NRR process but also offers a new intrinsic and universal descriptor φ. 展开更多
关键词 SACs Nitrogen reduction reaction C_(4)N_(4) intrinsic descriptor Machine learning
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部