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Chinese Journal of Poly.er Science 2002年第2期20卷 160-170页

作者： y. Men Fakultaet Fuer Phy.ik Albert-Ludwigs-Universitaet Freiburg 79104

The mechanism of tensile deformation in semi-cry.talline poly.ers was studied based on true stress-strain curvesobtained with the aid of a video-controlled tensile set-up. The deformation is affected by.both the cry.talline and theamorphous phases. However, the relative weights of the two portions change with the deformation stage. At lowdeformations the coupling and coarse slips of the cry.talline blocks dominate the mechanical properties, which allows thesy.tem to maintain a homogeneous strain distribution in the sample. As the stretching increases, at a critical strain the forcegenerated from entangled fluid portions reaches a critical value to destroy.the cry.tallites. The dominant deformationmechanism then changes into a disaggregation - recry.tallization process.

关键词： Semi-cry.talline poly.er Deformation mechanism Network Mechanical property

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Rey.oso Iván y.Hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity.to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry.hot season when biomass burning activity.is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the New *** applied a factor separation technique and process analy.is to estimate the pure and sy.ergistic contributions of emission reductions under lockdown and that from biomass burning to daily.ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely.masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by.changing the regional background levels which potentially.could bias high ozone production efficiency.*** the Megalopolis contribution to economic and societal development at national scale,our study.suggests that ozone mitigation measures during the dry.hot season targeting mainly.mobile emissions will likely.be offset by.biomass burning plumes.A regional and sy.ergic policy.aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analy.is

Inclusion of CoTiO_(3) to ameliorate the re/dehy.rogenation properties of the Mg–Na–Al sy.tem

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Journal of Magnesium and Alloy. 2024年第3期12卷 1215-1226页

作者： N.A.Ali N.y.y.snizam N.A.Sazelee Sami-ullah Rather Haizhen Liu M.Ismail Energy.Storage Research Group Faculty of Ocean Engineering TechnologyUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Department of Chemical and Materials Engineering King Abdulaziz UniversityP.O.Box80204Jeddah 21589Saudi Arabia Guangxi Novel Battery.Materials Research Center of Engineering Technology School of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key.Laboratory.of Featured Metal Materials and Life-Cy.le Safety.for Composite Structures Nanning 530004China

For the first time,the MgH_(2)–NaAlH_(4)(ratio 4:1)destabilized sy.tem with CoTiO_(3) addition has been *** CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample begins to dehy.rogenate at 130℃,which is declined by.40℃ compared to the undoped MgH_(2)–NaAlH_(4).Moreover,the de/rehy.rogenation kinetics characteristics of the CoTiO_(3)-doped MgH_(2)–NaAlH_(4) were greatly.*** the inclusion of CoTiO_(3),the MgH_(2)–NaAlH_(4) composite absorbed 5.2 wt.%H_(2),higher than undoped MgH_(2)–NaAlH_(4).In the context of dehy.rogenation,the CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample desorbed 2.6 wt.%H_(2),almost doubled compared to the amount of hy.rogen desorbed from the undoped MgH_(2)–NaAlH_(4) *** activation energy.obtained by.the Kissinger analy.is for MgH_(2) decomposition was significantly.lower by.35.9 kJ/mol than the undoped MgH_(2)–NaAlH_(4) *** reaction mechanism demonstrated that new phases of MgCo and AlTi_(3) were generated in situ during the heating process and are likely.to play.a substantial cataly.ic function and be useful in ameliorating the de/rehy.rogenation properties of the destabilized MgH_(2)–NaAlH_(4) sy.tem with the inclusion of CoTiO_(3).

关键词： Destabilize sy.tem Magnesium hy.ride Sodium alanate Hy.rogen storage Additive.

Selection criteria of MPOB-Angola germplasm collection for y.eld improvement of the oil palm

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Oil Crop Science 2024年第1期9卷 20-28页

作者： A.Norziha Z.Zamri y.Zulkifli A.M.Fadila M.Marhalil Malay.ian Palm Oil Board 6Persiaran InstitusiBandar BaruBangi43000KajangSelangorMalaysia Institute of Sy.tem Biology Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia

Oil palm germplasm collected from Angola,Africa in 1991 were subjected to genetic variability.potential *** collection was planted in the form of open-pollinated families as trials at the Malay.ian Palm Oil Board(MPOB)Kluang Research Station,Johor,Malay.ia,in *** palms from 52 families and tenera palms from 44 families of MPOB-Angola were evaluated for their bunch y.eld and bunch quality.*** objectives of this study.were to determine the genetic variability.among the families and performance of MPOB-Angola germplasm for y.eld *** analy.is of variance(ANOVA)revealed highly.significant differences between the dura and tenera families for most of the traits,suggesting the presence of high genetic variability.which is essential for breeding *** the duras,family.AGO 02.02 display.d the best y.eld performance,with a high fresh fruit bunch,oil y.eld and total economic product at 240.40,29.46 and 37.93 kg palm^(-1)y.ar^(-1),*** for the teneras,family.AGO 03.04 recorded the highest FFB y.eld and oil y.eld at 249.25 and 45.22 kg palm^(-1)y.ar^(-1),*** that,several families with big fruit sizes or producing a mean fruit weight of 14-17 g were also *** dura and tenera from AGO 01.01 recorded the highest oil to bunch(O/B)of 17.76%and 28.65%,*** findings will facilitate the selection of palms from the MPOB-Angola germplasm for future breeding programmes.

关键词： Oil palm Germplasm Genetic variability Heritability y.eld improvement

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang y.Chen W.B.y.o C.Z.Xiao J.F.My.tt School of Phy.ics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Phy.ics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by.the 2D PIC simulations under ty.ical conditions of a direct-drive inertial confinement fusion *** electrons produced by.second-order SRSS propagate nearly.perpendicular to the density.gradient and gain nearly.the same energy.as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： Victor V.Chizhikov Igor y.Iskusny.h Department of Anatomy.and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply.secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embry.nic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analy.is in *** cortical hem produces several ty.es of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly.important for the development of the hippocampus,which is involved in learning and memory.and the neocortex,which is the most complex brain region that mediates multiple ty.es of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

Effect of Eu^(3+),Bi^(3+),and Li^(+) doping on luminescent property.of GdNbO_(4)

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Journal of Rare Earths 2024年第1期42卷 66-75,I0003页

作者： S.W.Wi y.S.Lee Department of Phy.ics and Integrative Institute of Basic Sciences Soongsil UniversitySeoul06978Republic of Korea

We investigated the emission properties of Eu^(3+)-doped GdNbO_(4)-based oxide phosphors,aiming at improving the Eu^(3+)emission by.codoping of Bi^(3+)and Li^(+).Eu^(3+)singly.doped,Eu^(3+)and Bi^(3+)doubly.doped,and Eu^(3+),Bi^(3+),and Li^(+)triply.doped GdNbO_(4)were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu^(3+)in the singly.doped samples are significantly.improved by.the codoping of Bi^(3+),mainly.due to the energy.transfer from Bi^(3+)to Eu^(3+).The additional codoping of Li^(+)is found to increase the Eu^(3+)emission *** improvement might be attributed to the increase in the photoluminescent quantum y.eld originating from larger grain sizes and better cry.tallinity.A detailed analy.is of the X-ray.diffraction pattern and the asy.metric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu^(3+)in GdNbO_(4)does not change significantly.with the codoping of Bi^(3+)and Li^(+).Our results indicate that Li^(+)doping is a promising way.to improve the emission properties of rare-earth ion-doped GdNbO_(4)phosphors.

关键词： Eu^(3+) GdNbO_(4) Codoping of Li^(+) Photoluminescence Sensitizer Rare earths

Tailored architecture of composite electroly.e for all-solid-state sodium batteries with superior rate performance and cy.le life

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Nano Research 2024年第5期17卷 4171-4180页

作者： Xiang Guan Zhenhua Jian Xingan Liao Wenchao Liao y.nfei Huang Dazhu Chen Robert K.y.Li Chen Liu Shenzhen Key.Laboratory.of Poly.er Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518055China Department of Materials Science and Engineering City University of Hong KongHong KongChina

Seeking for composite electroly.es reinforced all-solid-state sodium ion batteries with superior long lifespan and rate performance remains a great ***,a unique strategy.to tailor the architecture of composite electroly.e via inserting poly.er chains into a small quantity.of sulfate sodium grafted C_(48)0H_(28)O_(32)Zr_(6)(UIOSNa)is *** intimate contact between poly.er segments and UIOSNa with limited pore size facilitates the anion immobilization of sodium salts and reduction of poly.er cry.tallinity.thereby.providing rapid ion conduction and reducing the adverse effect caused by.the immigration of *** tNa+grafting of-SO_(3)Na groups on fillers allows the free movement of more sodium ions to further improve and ionic ***,even with the low content of UIOSNa fillers,a high ionic conductivity.of 6.62×10^(-4) S·cm^(-1) at 60℃ and a transference number of 0.67 for the special designed composite electroly.e are *** assembled all-solid-state sodium cell exhibits a remarkable rate performance for 500 cy.les with 95.96%capacity.retention at a high current rate of 4 *** corresponding pouch cell can stably.work for 1000 cy.les with 97.03%capacity.retention at 1 C,which is superior to most of the reported composite electroly.es in the literature.

关键词： solid state sodium battery composite electroly.e rate performance cy.le life

Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy.logic,and artificial neural network

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Journal of Mountain Science 2024年第9期21卷 3108-3122页

作者： y.NKÜL Kaan KARAÇOR Fatih GÜRBÜZ Ay.an BUDAK TahsinÖmür Department of Civil Engineering Faculty of Engineering and ArchitectureTokat Gaziosmanpaşa UniversityTokat 60100Türkiye Department of Civil Engineering Faculty of Engineering and ArchitectureKafkas UniversityKars 36000Türkiye Department of Civil Engineering Faculty of EngineeringGazi UniversityAnkara 06570Türkiye Ministry.of y.uth and Sports Ankara 06090Türkiye

This study.aims to predict the undrained shear strength of remolded soil samples using non-linear regression analy.es,fuzzy.logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,utilizing six different measurement *** water content,plastic limit,and liquid limit were used as input parameters for fuzzy.logic and artificial neural network modeling,liquidity.index or water content ratio was considered as an input parameter for non-linear regression *** non-linear regression analy.es,12 different regression equations were derived for the prediction of undrained shear strength of remolded ***-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the Mamdani inference sy.tem was preferred with trapezoidal and triangular membership functions for fuzzy.logic *** experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for *** was observed that the accuracy.of the artificial neural network and fuzzy.logic modeling was higher than that of the non-linear regression ***,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination.

关键词： Undrained shear strength Liquidity.index Water content ratio Non-linear regression Artificial neural networks Fuzzy.logic

Cost effectiveness of nonpharmacological prevention programs for diabetes:A sy.tematic review of trial-based studies

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Chronic Diseases and Translational Medicine 2024年第1期10卷 12-21页

作者： y.ngy. Xiong Zhaohua Huo Samuel y.S.Wong Benjamin H.K.y.p Jockey.Club School of Public Health and Primary.Care Prince of Wales HospitalThe Chinese University of Hong KongShatinHong KongChina

Trial-based economic value of prevention programs for diabetes is *** aimed to review the cost-effectiveness of nonpharmacological interventions to prevent ty.e-2 diabetes mellitus(T2DM)for high-risk *** electronic databases were searched up to March *** assessing both the cost and health outcomes of nonpharmacological interventions for people at high-risk of T2DM were *** quality.of the study.was assessed by.the Consolidated Health Economic Evaluation Reporting Standards 2022 *** primary.outcome for sy.thesis was incremental cost-effectiveness ratios(ICER)for quality.adjusted life y.ars(QALy.),and costs were standardized in 2022 US *** sy.thesis was performed,considering different ty.es and delivery.methods of *** studies included five based on the US diabetes prevention program(DPP),six on non-DPP-based lifesty.e interventions,four on health education,and one on screening plus lifesty.e *** with usual care,lifesty.e interventions showed higher potential of cost-effectiveness than educational *** lifesty.e interventions,DPP-based programs were less cost-effective(median of ICERs:$27,077/QALy.than non-DPP-based programs(median of ICERs:$1395/QALy.from healthcare perspectives,but with larger decreases in diabetes ***,the cost-effectiveness of interventions was more possibly.realized through the combination of different delivery.*** interventions to prevent T2DM in high-risk populations are both cost-effective and feasible in various ***,economic evidence from low-and middle-income countries is still lacking,and interventions delivered by.trained lay.ersons and combined with peer support sessions or mobile technologies could be potentially.a cost-effective solution in such settings with limited resources.

关键词： economic evaluation nonpharmacological interventions pre-diabetes prevention