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Diketopiperazines with anti-skin inflammation from marine-derived endophytic fungus Aspergillus sp.and configurational reassignment of aspertryptanthrins
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作者 Jin Yang Xianmei Xiong +7 位作者 Lizhi Gong Fengyu Gan Hanling Shi Bin Zhu Haizhen Wu Xiujuan Xin Lingyi Kong Faliang An 《Chinese Journal of Natural Medicines》 2025年第8期980-989,共10页
Two novel diketopiperazines(1 and 5),along with ten known compounds(2−4,6−12)demonstrating significant skin inflammation inhibition,were isolated from a marine-derived fungus identified as Aspergillus sp.FAZW0001.The ... Two novel diketopiperazines(1 and 5),along with ten known compounds(2−4,6−12)demonstrating significant skin inflammation inhibition,were isolated from a marine-derived fungus identified as Aspergillus sp.FAZW0001.The structural elucidation and configurational reassessments of compounds 1−5 were established through comprehensive spectral analyses,with their absolute configurations determined via single crystal X-ray diffraction using Cu Kαradiation,Marfey’s method,and comparison between experimental and calculated electronic circular dichroism(ECD)spectra.Compounds 1,2,and 8 exhibited significant anti-inflammatory activities in Propionibacterium acnes(P.acnes)-induced human monocyte cell lines.Compound 8 demonstrated the ability to down-regulate interleukin-1β(IL-1β)expression by inhibiting Toll-like receptor 2(TLR2)expression and modulating the activation of myeloid differentiation factor 88(MyD88),mitogen-activated protein kinase(MAPK),and nuclear factorκB(NF-κB)signaling pathways,thus reducing the cellular inflammatory response induced by P.acnes.Additionally,compound 8 showed the capacity to suppress mitochondrial reactive oxygen species(ROS)production and nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)inflammasome activation,thereby reducing IL-1βmaturation and secretion.A three-dimensional quantitative structure-activity relationships(3D-QSAR)model was applied to compounds 5−12 to analyze their anti-inflammatory structure-activity relationships. 展开更多
关键词 DIKETOPIPERAZINES Aspergillus sp. configurational reassignment Anti-skin inflammation
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Determination of neutron-skin thickness using configurational information entropy 被引量:10
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作者 Chun-Wang Ma Yi-Pu Liu +3 位作者 Hui-Ling Wei Jie Pu Kai-Xuan Cheng Yu-Ting Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第1期60-66,共7页
Configurational information entropy(CIE)theory was employed to determine the neutron-skin thickness of neutron-rich calcium isotopes.The nuclear density distributions and fragment cross sections in 350 MeV/u ^(40-60)C... Configurational information entropy(CIE)theory was employed to determine the neutron-skin thickness of neutron-rich calcium isotopes.The nuclear density distributions and fragment cross sections in 350 MeV/u ^(40-60)Ca+^(9)Be projectile fragmentation reactions were calculated using a modified statistical abrasion-ablation model.CIE quantities were determined from the nuclear density,isotopic,mass,and charge distributions.The linear correlations between the CIE determined using the isotopic,mass,and charge distributions and the neutron-skin thickness of the projectile nucleus show that CIE provides new methods to extract the neutron-skin thickness of neutron-rich nuclei. 展开更多
关键词 Neutron-skin thickness configurational information entropy Cross section distribution Projectile fragmentation
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Thermoelectric performance of(AgBiTe_(2))_(1-x)(SnTe)_(x) with stable cubic enabled by enhanced configurational entropy 被引量:6
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作者 Ting Zhao Li-Ze Yang +5 位作者 Yun Zhou Hui-Jun Liao Zheng-Yong Huang Jian Li Xu Lu Xiao-Yuan Zhou 《Rare Metals》 SCIE EI CAS CSCD 2022年第12期4149-4155,共7页
ABX_(2)(A=Ag,Na,Cu;B=Sb,Bi;X=S,Se,Te)(GroupsⅠ-Ⅴ-Ⅵ_(2))compounds,which are all characterized by the ultralow lattice thermal conductivity because of their strong lattice anharmonicity caused by lone-pair electrons,h... ABX_(2)(A=Ag,Na,Cu;B=Sb,Bi;X=S,Se,Te)(GroupsⅠ-Ⅴ-Ⅵ_(2))compounds,which are all characterized by the ultralow lattice thermal conductivity because of their strong lattice anharmonicity caused by lone-pair electrons,have aroused wide attention in thermoelectric community.The practical application of thermoelectric devices usually requires both the compatible n-type and p-type materials simultaneously.However,most ofⅠ-Ⅴ-Ⅵ_(2)compounds are intrinsic p-type semiconductors,lacking their n-type counterparts for thermoelectrics.Herein,in this work,we increase the configuration entropy of AgBiTe_(2)by alloying SnTe,in order to stabilize the cubic phase at room temperature.With further optimization of thermal and electrical performance,the thermoelectric performance could be improved simultaneously in both n-and p-type(AgBiTe_(2))_(1-x)(SnTe)_(x)(x=0.3,0.4)solid solutions.Finally,p-type compound with the nominal composition of(AgBi_(0.99)Cd_(0.01)Te_(2))_(0.6)(SnTe)_(0.4)and n-type of(AgBiTe_(2))_(0.7)(SnTe)_(0.3)~Br 6%show the maximum zT of~0.33 and~0.21,at 381 and 423 K,respectively. 展开更多
关键词 configurational entropy Cubic phase Solid solutions THERMOELECTRICS
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Configurational information entropy analysis of fragment mass cross distributions to determine the neutron skin thickness of projectile nuclei 被引量:6
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作者 Hui-Ling Wei Xun Zhu Chen Yuan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第9期21-27,共7页
Configurational information entropy(CIE)analysis has been shown to be applicable for determining the neutron skin thickness(δnp)of neutron-rich nuclei from fragment production in projectile fragmentation reactions.Th... Configurational information entropy(CIE)analysis has been shown to be applicable for determining the neutron skin thickness(δnp)of neutron-rich nuclei from fragment production in projectile fragmentation reactions.The BNN+FRACS machine learning model was adopted to predict the fragment mass cross-sections(σ_(A))of the projectile fragmentation reactions induced by calcium isotopes from ^(36)Ca to ^(56)Ca on a ^(9)Be target at 140MeV/u.The fast Fourier transform was adopted to decompose the possible information compositions inσA distributions and determine the quantity of CIE(S_(A)[f]).It was found that the range of fragments significantly influences the quantity of S_(A)[f],which results in different trends of S_(A)[f]~δnp correlation.The linear S_(A)[f]~δnp correlation in a previous study[Nucl.Sci.Tech.33,6(2022)]could be reproduced using fragments with relatively large mass fragments,which verifies that S_(A)[f]determined from fragmentσAis sensitive to the neutron skin thickness of neutron-rich isotopes. 展开更多
关键词 Neutron skin thickness Mass cross-section distribution configurational information entropy Projectile fragmentation reaction
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Configurational entropy-induced phase transition in spinel LiMn_(2)O_(4) 被引量:1
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作者 Wei Hu Wen-Wei Luo +2 位作者 Mu-Sheng Wu Bo Xu Chu-Ying Ouyang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第9期592-596,共5页
The spinel-type LiMn_(2)O_(4) is a promising candidate as cathode material for rechargeable Li-ion batteries due to its good thermal stability and safety.Experimentally,it is observed that in this compound there occur... The spinel-type LiMn_(2)O_(4) is a promising candidate as cathode material for rechargeable Li-ion batteries due to its good thermal stability and safety.Experimentally,it is observed that in this compound there occur the structural phase transitions from cubic(Fd3m)to tetragonal(I4_(1)/amd)phase at slightly below room temperature.To understand the phase transition mechanism,we compare the Gibbs free energy between cubic phase and tetragonal phase by including the configurational entropy.Our results show that the configurational entropy contributes substantially to the stability of the cubic phase at room temperature due to the disordered Mn^(3+)/Mn^(4+)distribution as well as the orientation of the Jahn-Teller elongation of the Mn^(3+)O_(6) octahedron in the the spinel phase.Meanwhile,the phase transition temperature is predicted to be 267.8 K,which is comparable to the experimentally observed temperature.These results serve as a good complement to the experimental study,and are beneficial to the improving of the electrochemical performance of LiMn_(2)O_(4) cathode. 展开更多
关键词 configurational entropy LiMn_(2)O_(4) phase transition Jahn-Teller distortion
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High-throughput investigations of configurational-transformation-dominated serrations in CuZr/Cu nanolaminates
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作者 William Yi Wang Bin Gana +15 位作者 Deye Lin Jun Wang Yiguang Wang Bin Tang Hongchao Kou Shunli Shang Yi Wang Xingyu Gao Haifeng Song Xidong Hui Laszlo J.Kecskes Zhenhai Xia Karin A.Dahmen Peter K.Liaw Jinshan Lia Zi-Kui Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第18期192-199,共8页
Metallic amorphous/crystalline(A/C)nanolaminates exhibit excellent ductility while retaining their high strength.However,the underlying physical mechanisms and the resultant structural changes during plastic deformati... Metallic amorphous/crystalline(A/C)nanolaminates exhibit excellent ductility while retaining their high strength.However,the underlying physical mechanisms and the resultant structural changes during plastic deformation still remain unclear.In the present work,the structure-property relationship of CuZr/Cu A/C nanolaminates is established through integrated high-throughput micro-compression tests and molecular dynamics simulations together with high-resolution transmission electron microcopy.The serrated flow of nanolaminates results from the formation of hexagonal-close-packed(HCP)-type stacking faults and twins inside the face-centered-cubic(FCC)Cu nano-grains,the body-centered-cubic(BCC)-type ordering at their grain boundaries,and the crystallization of the amorphous CuZr layers.The serration behavior of CuZr/Cu A/C nanolaminates is determined by several factors,including the formation of dense dislocation networks from the multiplication of initial dislocations that formed after yielding,weak-spots-related configurational-transitions and shear-transition-zone activities,and deformation-induced devitrification.The present work provides an insight into the heterogeneous deformation mechanism of A/C nanolaminates at the atomic scale,and mechanistic base for the microstructural design of self-toughening metallic-glass(MG)-based composites and A/C nanolaminates. 展开更多
关键词 NANOLAMINATES SERRATION configurational transformation Molecular dynamics Metallic glass
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COMPUTER SIMULATIONS ON UNPERTURBED CONFIGURATIONAL DIMENSIONS OF POLY (METHYL ACRYLATE)
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作者 贺子如 杨小震 +1 位作者 赵得禄 徐懋 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1996年第2期150-162,共13页
A full-relaxation optimization of molecule and the popular MM2 force field are employed to obtain the geometry parameters and the conformational energy surface of a meso or a racemic dyad of poly(methyl acrylate) (PMA... A full-relaxation optimization of molecule and the popular MM2 force field are employed to obtain the geometry parameters and the conformational energy surface of a meso or a racemic dyad of poly(methyl acrylate) (PMA) with a specified carbonyl-bond orientation in side-groups. It is found that the conformational energy maps calculated here considerably differ from those calculated with the rigid molecular model as reported in the earlier studies. The g(-) state cannot be omitted in the obtained contour maps. Two important conformers tg(-) and g(-t) with energy minima were newly detected for a racemic dyad. The analysis on the conformations with energy minima confirmed that the ester groups are not always perpendicular to the plane defined by the two adjacent skeletal bonds and may change their relative orientations to meet the requirement of lower energies during the conformational state transition. Instead of the early way of adjusting the interaction energy parameters to fit the experimental data, we attempt to predict unperturbed chain dimensions via the reliable force field and the configurational statistical mechanics. The proposed scheme with three rotational states identified from the contour maps allowed us to satisfactorily reproduce the experimental dimensions of random PMA chains. 展开更多
关键词 poly(methyl acrylate) configurational statistics conformational energy
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Spatiotemporal variations,influencing factors,and configurational promotion paths of energy efficiency in China’s cities
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作者 Ruyu Xu Keliang Wang +1 位作者 Zhuang Miao Lingxuan Sun 《Chinese Journal of Population,Resources and Environment》 2024年第1期74-86,共13页
The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration p... The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration promotion paths of EE in 284 Chinese cities during 2003‒2019 using the global super-efficiency minimum distance to strong efficient frontier(G-S-MinDS),exploratory spatial data analysis(ESDA),multiscale geographically weighted regression(MGWR),and fuzzy set qualitative comparative analysis(fsQCA)methods.The findings are:①China’s cities have an annual average EE of 0.658 with a growth rate of 0.53%,showing considerable promotion potential.②Industrial structure optimization,population agglomeration,economic development,and increased green coverage contribute positively,while government intervention and openness hinder China’s urban EE.③Four configurational promotion paths for enhancing China’s urban EE are identified,where among those paths population density is a core condition,while government intervention is not.This study provides valuable insights into substantially improving urban EE,emphasizing the need for targeted policies to address energy and environmental crises in China. 展开更多
关键词 Energy efficiency Spatiotemporal variations Influencing factors configurational promotion paths
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Managing Accessibility- The Configurational Approach to the Inclusive Design of Urban Spaces
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《Journal of Civil Engineering and Architecture》 2012年第4期444-456,共13页
This paper concerns the theme of the universal accessibility to urban spaces, proposing the contribution of configurational approach to their inclusive design. Born in the first Nineties on the roots of the efforts an... This paper concerns the theme of the universal accessibility to urban spaces, proposing the contribution of configurational approach to their inclusive design. Born in the first Nineties on the roots of the efforts and the studies for reducing material and architectural barriers for disabled people, such discipline extends its sphere and purposes so as to mitigate the effects of spatial exclusion of a wider and wider variety of human categories, up to virtually include any potential urban user. Several questions persuade that a merely functional approach, essentially based on the position of the located activities, cannot be said satisfying: only a configurational approach can account for the effects of the grid configuration on the actual accessibility of its spaces. Our research focuses on Italian urban settlements, which appear as ideal case studies, due to the typical consistency of their urban spaces, which, especially in the inner historical cores, are densely build, geometrically irregular and hence generally far from actually providing a universal material accessibility. Here the impedance of space is much more than a theoretical hypothesis and concrete interventions are generally requested to eliminate or reduce its barriers and to make space actually and safely usable. Rather than at indicating the technical solution of single urban problems, which of course are strongly different each other, the research aims at defining a method suitable for any local context. Such method, integrating into a reliable tool the configurational vision with the functional and interactional approach, will provide a hierarchy of urban spaces with reference to the necessity of their universal accessibility. 展开更多
关键词 ACCESSIBILITY configurational analysis inclusive design town planning
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Enhancing electrocaloric effects of KNN-based ceramics by phase-and ion-configurational entropy regulation based on phase-field modeling
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作者 Xiaoqian Wu Guohui Li +2 位作者 Bo Shen Houbing Huang Jiwei Zhai 《npj Computational Materials》 2025年第1期3373-3384,共12页
Potassium-sodium niobate(KNN)-based piezoelectric materials demonstrate exceptional electrocaloric(EC)optimization potential owing to phase configurational diversity,though current performance remains constrained by i... Potassium-sodium niobate(KNN)-based piezoelectric materials demonstrate exceptional electrocaloric(EC)optimization potential owing to phase configurational diversity,though current performance remains constrained by insufficient entropy modulation.This study establishes highentropy strategies-particularly phase/ion-configurational entropy(I-PCE)synergistic regulation-as a critical pathway to transcend conventional EC entropy change(ΔS_(ECE))limits.Phase-field modeling of Rhombohedral-Orthorhombic-Tetragonal-Cubic(R-O-T-C)phase evolution reveals thatΔSECE is governed by three hierarchical factors:phase configurational entropy(Sconfig_phase,dominant),ion configurational entropy(Sconfig_ion),and polarization response.Notably,polarization response in R-phase supersedes O-phase entropy contributions,establishing a performance hierarchy.Based on I-PCE optimization,R-O-dominated multiphase coexistence achieves aΔS_(ECE)exceeding 19 J/kg/K at 52.80μC/cm^(2)reversible polarization.Further achieving enhanced polarization(100μC/cm^(2))yields aΔS_(ECE)of 73 J/kg/K,establishing the experimental EC upper bound for KNN systems via high entropy-driven design.We anticipate that these discoveries will provide theoretical guidelines for tailoring EC effects in multiphase-configurational material systems via high-entropy strategies. 展开更多
关键词 entropy modulationthis phase configurational entropy highentropy strategies particularly phase configurational diversitythough ion configurational entropy piezoelectric materials electrocaloric phase field modeling
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Tellurazole/Tellurazolium Based Olefin Configurational Photoswitches Controlled by Noncovalent Interactions
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作者 Peng He Hebo Ye +3 位作者 Shuaipeng Jia Qinhua Rao Yong Zhou Lei You 《CCS Chemistry》 2025年第6期1698-1710,共13页
Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazoliu... Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazolium-based olefin scaffolds,wherein intramolecular through-space n→π^(*)orbital interaction plays a stabilizing role in the Z isomer approaching quantitative conversion.The manipulation of diverse noncovalent interactions,including intermolecular chalcogen bonding,further provided versatile handles for regulating molecular recognition and multiaddressable switching.Despite bidirectional E/Z photoisomerization with neutral tellurazole derivatives,protonation-induced cationic tellurazoliums allowed significant enhancement in the efficiency of Z→E switching(E up to 73%)while maintaining high percentage E→Z switching(Z up to 95%),as chalcogen bonding with counteranions contributes to the stabilization of electron-accepting tellurazoliums affording a larger wavelength difference between E/Z isomers.Furthermore,the n→π^(*)orbital interaction enables the preference of Z isomer in the ground state for N-methyl tellurazoliums.Bidirectional E/Z photoswitching with high conversion(Z up to 99%,E up to 81%)was attained,and E→Z isomerization can also be invoked by nucleophilic catalysis,making N-methyl tellurazoliums as T-type photoswitches.The results showcase the power of noncovalent interactions for controlling molecular photoswitches and should set the scene for vip recognition,dynamic assemblies,and responsive materials. 展开更多
关键词 PHOTOSWITCH orbital interaction chalcogen bond configurational switch molecular recognition
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Optimization of Coulomb energies in gigantic configurational spaces of multielement ionic crystals
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作者 Konstantin Köster Tobias Binninger Payam Kaghazchi 《npj Computational Materials》 2025年第1期2168-2180,共13页
Most of the novel energy materials contain multiple elements occupying a single site in their lattice.The exceedingly large configurational space of these materials imposes challenges in determining low(est)energy str... Most of the novel energy materials contain multiple elements occupying a single site in their lattice.The exceedingly large configurational space of these materials imposes challenges in determining low(est)energy structures.Coulomb energies of possible configurations generally show a satisfactory correlation to computed energies at higher levels of theory and thus allow to screen for minimumenergy structures.Employing an expansion into a binary optimization problem,we obtain an efficient Coulomb energy optimizer using Monte Carlo and Genetic Algorithms.The presented optimization package,GOAC(Global Optimization of Atomistic Configurations by Coulomb),can achieve a speed up of several orders of magnitude compared to existing software.In this work,heuristic optimization on various material classes is performed.Thus,GOAC provides an efficient method for constructing low-energy atomistic models for ionic multi-element materials with gigantic configurational spaces. 展开更多
关键词 novel energy materials Monte Carlo binary optimization problemwe screen minimumenergy structuresemploying genetic algorithms multielement ionic crystals configurational space Coulomb energies
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High-Entropy Oxide Memristors for Neuromorphic Computing:From Material Engineering to Functional Integration
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作者 Jia‑Li Yang Xin‑Gui Tang +4 位作者 Xuan Gu Qi‑Jun Sun Zhen‑Hua Tang Wen‑Hua Li Yan-Ping Jiang 《Nano-Micro Letters》 2026年第2期138-169,共32页
High-entropy oxides(HEOs)have emerged as a promising class of memristive materials,characterized by entropy-stabilized crystal structures,multivalent cation coordination,and tunable defect landscapes.These intrinsic f... High-entropy oxides(HEOs)have emerged as a promising class of memristive materials,characterized by entropy-stabilized crystal structures,multivalent cation coordination,and tunable defect landscapes.These intrinsic features enable forming-free resistive switching,multilevel conductance modulation,and synaptic plasticity,making HEOs attractive for neuromorphic computing.This review outlines recent progress in HEO-based memristors across materials engineering,switching mechanisms,and synaptic emulation.Particular attention is given to vacancy migration,phase transitions,and valence-state dynamics—mechanisms that underlie the switching behaviors observed in both amorphous and crystalline systems.Their relevance to neuromorphic functions such as short-term plasticity and spike-timing-dependent learning is also examined.While encouraging results have been achieved at the device level,challenges remain in conductance precision,variability control,and scalable integration.Addressing these demands a concerted effort across materials design,interface optimization,and task-aware modeling.With such integration,HEO memristors offer a compelling pathway toward energy-efficient and adaptable brain-inspired electronics. 展开更多
关键词 High-entropy oxides MEMRISTORS Neuromorphic computing configurational entropy Resistive switching
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Pressure-Modulated Activation Energy as a Unified Descriptor of Mechanical Behavior in Metallic Glass
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作者 Huanrong Liu Jian Li +1 位作者 Shan Zhang Pengfei Guan 《Chinese Physics Letters》 2026年第1期71-82,共12页
The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ... The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ simulations with varied protocols to evaluate the effectiveness of different descriptors in predicting mechanical properties across both low-and high-pressure regimes.Our findings demonstrate that conventional structural and configurational descriptors fail to correlate with the mechanical response following pressure release,whereas the activation energy descriptor exhibits robust linearity with shear modulus after correcting for pressure effects.Notably,the soft mode parameter emerges as an ideal and computationally efficient alternative for capturing this mechanical behavior.These findings provide critical insights into the influence of pressure on glassy properties,integrating the distinct features of compressed glasses into a unified theoretical framework. 展开更多
关键词 pressure modulated activation energy predicting mechanical properties metallic glass relaxation processes functional properties mechanical behavior simulations varied protocols structural configurational descriptors
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Conformational Energy and Configurational Statistics of Polyacrylamide 被引量:1
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作者 贺子如 杨小震 徐懋 《Chinese Science Bulletin》 SCIE EI CAS 1994年第13期1086-1091,共6页
One sort of very important polyelectrolytes, polyacrylamide (PAA) and its copolymers with acrylic acid, on the one hand, have been widely applied as commercial products as flocculants and mobility control fluids in en... One sort of very important polyelectrolytes, polyacrylamide (PAA) and its copolymers with acrylic acid, on the one hand, have been widely applied as commercial products as flocculants and mobility control fluids in enhanced oil recovery. On the other hand, these polymers relate to the fundamental point of polymer physics, a configuration of very long chain molecules containing many hydrogen-bonding groups. 展开更多
关键词 confonnational ENERGY configurational STATISTICS polyacrylamide.
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Thermodynamic Correlation Between Surface Carboxyl Configuration and Wettability
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作者 GUO Zhuohuan WANG Dayang 《高等学校化学学报》 北大核心 2026年第1期255-266,共12页
In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using at... In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using attenuated total reflectance Fourier-transform infrared spectroscopy(ATR-FTIR),the molecular configurations of surface carboxyl groups(COOH),free carboxyl(COOH_(f))and hydrogen-bonded carboxyl(COOH_(HB),were directly correlated with the polar component of surface energy(γ^(s,p)).By decomposing theγ^(s,p)values of the PAA thin films as a sum of the contributions of COOH_(f)and COOH_(H B),the intrinsic polar component of surface energy of COOH_(H B)(γ_(H B)^(s,p*))was quantified for the first time as 8.34 mN/m,significantly lower than that of COOH_(f)(γ_(f)^(s,p*)=34 mN/m).This result highlights that hydrogen bonding markedly reduces theγ^(s,p),providing a rational explanation for the relatively large water contact angle observed on PAA thin films.Furthermore,it establishes a thermodynamic basis for estimating the fraction of surface COOH_(H B)groups(f H B)from wettability measurements.Further extension of the model to carboxyl-terminated self-assembled monolayers(COOH-SAMs)revealed that surface COOH density(ΣCOOH)critically regulates wetting behavior:whenΣCOOH ranges from 4.30 to 5.25 nm^(-2),COOH groups predominantly exist in a free state and facilitate effective hydration layers,thereby promoting superhydrophilicity.Overall,this study not only establishes a unified thermodynamic framework linking surface COOH configurations to macroscopic wettability,but also validates its universality by extending it to COOH-SAMs systems,thereby providing a unified theoretical framework for the controllable design of hydrophilicity in various COOH-functionalized surfaces. 展开更多
关键词 Polyacrylic acid film Hydrogen bonding Attenuated total reflectance Fourier-transform infrared spectroscopy Quantitative carboxyl configuration Polar component of surface energy
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Absolute Configurational Assignments of Amino Acid Esters by a CD-Sensitive Malonamide-Linked Zinc Bisporphyrinate Host
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作者 Baozhen Liu Jiaxun Jiang +1 位作者 Xianshi Fang Chuanjiang Hu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2014年第8期797-802,共6页
A novel malonamide-linked zinc bisporphyrinate[Zn_(2)-1]has been designed and synthesized.UV-vis and NMR spectroscopic studies suggest the molecule aggregates in solution.Such zinc bisporphyrinate is very CD-sensitive... A novel malonamide-linked zinc bisporphyrinate[Zn_(2)-1]has been designed and synthesized.UV-vis and NMR spectroscopic studies suggest the molecule aggregates in solution.Such zinc bisporphyrinate is very CD-sensitive when it is mixed with amino acid ethyl esters.The amplitude value of the induced circular dichroism(ICD)is up to ca.1500 L•mol^(−1)•cm^(−1).Further studies by ^(1)H NMR and UV-vis spectroscopies reveal amino acid esters function as monodentate ligands,and[Zn_(2)-1]interacts with amino acid ethyl esters through coordination and hydrogen bonding interactions. 展开更多
关键词 bisporphyrin MALONAMIDE configurational assignment amino acid ester
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Revision of the absolute configurations of Pallavicinia diterpenoids and further discovery of their Diels-Alder cycloadducts
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作者 Jiao-Zhen Zhang Cheng-Min Zhang +7 位作者 Yong-Jie Wang Pei-Lin Wu Rui-Feng Liu Ye Li Ming-Zhu Zhu Shuang-Zhi Yuan Ze-Jun Xu Hong-Xiang Lou 《Chinese Chemical Letters》 2026年第1期394-398,共5页
Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is c... Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is crucial for the confirmation of absolute configurations.Ignoring critical parameters will lead to false structure,which may confuse the total synthesis and drug development.Herein,the configurations of seven heterogeneous Pallavicinia diterpenoids(PDs) isolated from Pallavicinia liverworts are revised using a combination of single-crystal X-ray diffraction and electronic circular dichroism(ECD) calculations.Meanwhile,identification of five unprecedented PD heterodimers PD-dimers A-E(18-22) along with eleven previously undescribed PDs(5-9,13-17,23) obtained by the reinvestigation of the Chinese liverwort Pallavicinia subciliata have resulted in corrections and support the revised conclusions. 展开更多
关键词 REVISION Absolute configurations Pallavicinia diterpenoids LIVERWORT Single-crystal X-ray diffraction Electronic circular dichroism calculations
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Analysis of Geometrical Arrangement and Packing Material on Heat Generation in Lithium-Ion Battery Banks
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作者 Seenaa Khudhayer Salman Shaymaa Husham Abdulmalek +2 位作者 Ali Ahmed Gitan Thamer Khalif Salem Raaid Rashad Jassem Al-Doury 《Energy Engineering》 2026年第2期578-601,共24页
Operating Lithium-ion batteries at their temperature limits is a challenging design task due to explosion risk at high temperatures and rapid degradation at low temperatures.Depending on the battery package design,tho... Operating Lithium-ion batteries at their temperature limits is a challenging design task due to explosion risk at high temperatures and rapid degradation at low temperatures.Depending on the battery package design,those risks can be solved with passive solutions,which require no active cooling or heating.Thecurrentwork aims to optimize the pack design and materials of the type-NCR18650B battery based on a wide range of operation temperature.The lower limit was denoted by cold case while the maximum limit was expressed by hot case.A combined analyticalnumerical approach was developed to model the heat generation inside the battery.A thermal resistance analysis was used to determine the boundary conditions of the numerical model.The governing differential equations for the 1-D heat generation model were solved analytically.The numerical analysis was considered to determine the best battery pack design based on material parameters,number of batteries,and geometrical arrangement.The analytical results revealedthat the cold case canbe selectedas theworst case and thebestmodel wasobtainedusing thehexagonal-shaped 10-battery pack that was covered with Delrin of 1.8 mm in thickness.The numerical results showed that the best model was the hexagonal-shaped 10-battery pack with Delrin of 2 mm in thickness that achieved the largest temperature of−20.6℃ in the cold case. 展开更多
关键词 Analytical analysis battery package battery package configuration battery packing safety lithium-ion battery thermal performance
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Optimal Allocation of Multiple Energy Storage Capacity in Industrial Park Considering Demand Response and Laddered Carbon Trading
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作者 Jingshuai Pang Songcen Wang +5 位作者 Hongyin Chen Xiaoqiang Jia YiGuo Ling Cheng Xinhe Zhang Jianfeng Li 《Energy Engineering》 2026年第1期136-152,共17页
To achieve the goals of sustainable development of the energy system and the construction of a lowcarbon society,this study proposes a multi-energy storage collaborative optimization strategy for industrial park that ... To achieve the goals of sustainable development of the energy system and the construction of a lowcarbon society,this study proposes a multi-energy storage collaborative optimization strategy for industrial park that integrates the laddered carbon trading mechanism with demand response.Firstly,a dual dimensional DR model is constructed based on the characteristics of load elasticity.The alternativeDRenables flexible substitution of energy loads through complementary conversion of electricity/heat/cold multi-energy sources,while the price DR relies on timeof-use electricity price signals to guide load spatiotemporal migration;Secondly,the LCT mechanism is introduced to achieve optimal carbon emission costs through a tiered carbon quota allocation mechanism.On this basis,an optimization decision model is established with the core objective of maximizing the annual net profit of the park.The objective function takes into account energy sales revenue,generator unit costs,and investment and operation costs of multiple types of energy storage facilities.Themodel constraint system covers three key dimensions:dynamic operation constraints of power generation units,including unit output limits,ramping capability,and minimum start-stop time;the physical boundary of an electric/hot/cold multi-energy storage system involves energy storage capacity and charge/discharge efficiency;The multi-energy network coupling balance equation ensures that the energy conversion and transmission process satisfies the law of conservation of energy.Using CPLEX mathematical programming solver for simulation verification,construct an energy storage capacity configuration decision process that includes LCT-DR synergistic effect.The research results show that compared with the traditional single energy storage configuration mode,this strategy effectively enhances the economic feasibility and engineering practicality of industrial park operation by coordinating demand side resource scheduling and finely controlling carbon costs,while maintaining stable system operation.Its methodological framework provides a technical path that combines theoretical rigor and practical operability for the low-carbon transformation of regional integrated energy systems. 展开更多
关键词 Demand response laddered carbon trading combined cooling heating and power supply capacity configuration
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