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风化过程中铼和硒的活动性及其对化石有机碳风化的指示

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中国科学：地球科学 2024年第3期54卷 760-770页

作者：张玉红汪进曲远馨朱超金章东中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院大学北京100049 西安地球环境创新研究院西安710061 西安交通大学全球环境变化研究院西安710049

化石有机碳风化是地质时间尺度上重要的碳源,对全球碳循环和气候变化具有重要影响,但如何量化一直是个挑战.河水铼(Re)含量的变化被认为具有示踪流域化石有机碳风化强度的潜力,然而Re的来源及其与化石有机碳风化之间的关系还知之甚少.... 详细信息

化石有机碳风化是地质时间尺度上重要的碳源,对全球碳循环和气候变化具有重要影响,但如何量化一直是个挑战.河水铼(Re)含量的变化被认为具有示踪流域化石有机碳风化强度的潜力,然而Re的来源及其与化石有机碳风化之间的关系还知之甚少.为了更好地认识这一指标的有效性,本文选择重庆市城口县下寒武统水井沱组页岩风化剖面为研究对象,通过元素含量、逐级提取实验等分析,探讨页岩风化序列中Re和硒(Se)的活动性及其与化石有机碳风化的关系.结果表明,化学蚀变指数(CIA)从基岩到风化层逐步升高,指示增强的风化强度.根据逐级提取实验和质量迁移系数(τ)的变化发现,页岩中的Re和Se主要赋存于有机质相,风化过程中与化石有机碳同步流失,而与页岩中的硫化物矿物氧化无明显相关;风化过程中Re和Se不同的地球化学行为导致其与化石有机碳非等量流失.本研究支持Re作为示踪化石有机碳风化的指标,而Se是示踪化石有机碳风化的潜在指标.未来需要不同类型沉积岩剖面与流域相结合的研究,明确河水Re和Se的来源及其与流域化石有机碳风化之间的关系.

关键词： Re和Se 页岩活动性化石有机碳化学风化

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青少年手机冷落行为量表的编制及信效度检验

中国临床心理学杂志 2024年第4期32卷 875-881页

作者：何安明翟培培曲姿谕惠秋平信阳师范大学教育科学学院信阳464000 兰州大学哲学社会学院兰州730000

目的:在以往手机冷落行为相关研究的基础上,编制适用于我国青少年的手机冷落行为量表。方法:根据147名青少年(样本1)的调查结果编制问卷初稿,并由80名青少年(样本2)对条目可理解性与合理性进行评估,形成初始条目21个。对随机抽取的746... 详细信息

目的:在以往手机冷落行为相关研究的基础上,编制适用于我国青少年的手机冷落行为量表。方法:根据147名青少年(样本1)的调查结果编制问卷初稿,并由80名青少年(样本2)对条目可理解性与合理性进行评估,形成初始条目21个。对随机抽取的746名青少年(样本3)被试的问卷进行项目分析和探索性因素分析,对随机抽取的786名青少年(样本4)被试的问卷进行验证性因素分析和信效度检验。间隔两周后对来自样本3的88名青少年(样本5)进行青少年手机冷落行为量表重测。结果:最终形成的青少年手机冷落行为量表共19个项目,包含自我沉浸、他人反馈、缺乏控制和沟通干扰四个因子。量表及各因子的Cronbach’sα系数在0.84~0.93之间,重测相关系数在0.69~0.92之间。四因子模型拟合良好(χ^(2)/df=4.90,NFI=0.92,RFI=0.91,IFI=0.94,TLI=0.93,CFI=0.94,RMSEA=0.07)。量表各因子与总分之间的相关在0.77~0.81之间。量表总分及其各因子得分与中文版手机冷落行为量表总分、简版青少年智能手机成瘾量表总分和中文版无手机恐惧量表总分之间均呈显著正相关。结论:青少年手机冷落行为量表具有良好的信效度,适合用来测量我国青少年的手机冷落行为。

关键词：手机冷落行为信度效度青少年

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y-Ba-Cu-O mixed oxides for production of diphenols in liquid-solid phase

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Chinese Journal of Chemistry 1996年第6期14卷 516-524页

作者： Liu, CB zhao, z.y.ng, XG ye, XK Wu, y CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022JILINPEOPLES R CHINA

Superconductor mixed oxides were often used as catalysts at higher temperature in gas phase oxidations, and considered not suitable for lower temperature reactions in the liquid-solid phase; here the catalysis of yBa2Cu3O7+/-x and y2BaCuO5+/-x in the phenol hydroxylation at lower temperature with H2O2 as oxygen donor was studied, and found that the superconductor yBa2Cu3O7+/-x, has no catalytic activity for phenol hydroxylation, but y2BaCuO5+/-x does, even has better catalytic activity and stability than most previously reported ones. With the studies of catalysis of other simple metal oxides and perovskite-like mixed oxides, a radical substitution mechanism is proposed and the experimental facts are explained clearly, and draw a conclusion that the perovskite-like mixed oxides with (AO)(ABO(3)) and (AO)2(ABO(3)) structure have better catalytic activity than the simple perovskite oxides with (ABO(3))(3) structure alone, and (AO) structure unit is the key for the mixed oxides to have the phenol hydroxylation activity. No pollution of this process is very important for its further industrial application.

关键词： superconductor mixed oxides phenol hydroxylation radical substitution

Finite element analysis and experimental validation of polymer-metal contacts in block-on-ring configuration

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Friction 2024年第3期12卷 554-568页

作者： K.y.Eayal AWWAD Khosro FALLAHNEzHAD B.F.yOUSIF Ahmad MOSTAFA Omar ALAJARMEH A.SHALWAN Xuesen zENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for Future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analysis,obtained by different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study,the wear profile of polymer–metal contact,obtained by block-on-ring configuration under dry sliding conditions,was analysed using finite element modelling(FEM)and experimental ***’s wear equation was integrated into a developed FORTRAN-UMESHMOTION code linked with Abaqus software.A varying wear coefficient(k)values covering both running-in and steady state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** FEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify the critical zone where the stress concentration is the key point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately,SEM analysis showed severer damage features in the critical zone than that in the normal zone as proven by ***,the literature data presented and considered the wear features the same at any point of the wear *** this study,the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally different features from one another.

关键词： polymer-to-metal contact block-on-ring wear profile wear model

Resistive field generation in intense proton beam interaction with solid targets

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： W.Q.Wang J.J.Honrubia y.yin X.H.yang F.Q.Shao Department of Physics National University of Defense TechnologyHunanChina ETSI Aeronáutica y del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Technology National University of Defense TechnologyHunanChina

The Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed hybrid code to model ion beam-plasma *** simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in which they compete with each *** the target is not completely ionized,the self-generated resistive field effect dominates over the ion scattering ***,when the target is completely ionized,this situation is ***,it is found that Ohmic heating is important for higher current densities and materials with high *** energy fraction deposited as Ohmic heating can be as high as 20%-30%.Typical ion divergences with half-angles of about 5°-10°will modify the proton energy deposition substantially and should be taken into account.

关键词： interaction beam intense

Editorial for Multiscale&Multifield Coupling in Geomechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1919-1921页

作者： Min Wang Pengzhi Pan Andrew H.C.Chan y.T.Feng T-3 Fluid Dynamics and Solid Mechanics Theoretical DivisionLos Alamos National LaboratoryNew MexicoUSA Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhanChina School of Engineering University of TasmaniaTasmaniaAustralia College of Engineering Swansea UniversityWalesUK

We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical *** purpose of this special issue is dedicated to gathering the latest research work on Multiscale&Multifield Coupling in Geomechanics,where we delve into the intricate interplay of various fields and scales that govern the behavior of *** total,30 manuscripts from USA,China,UK,Germany,Canada,India and United Arab Emirates are selected to be included in this issue.

关键词： materials. gathering mechanics

Inclusion of CoTiO_(3) to ameliorate the re/dehydrogenation properties of the Mg–Na–Al system

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

作者： N.A.Ali N.y.yusnizam 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-Cycle Safety for Composite Structures Nanning 530004China

For the first time,the MgH_(2)–NaAlH_(4)(ratio 4:1)destabilized system with CoTiO_(3) addition has been *** CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample begins to dehydrogenate at 130℃,which is declined by 40℃ compared to the undoped MgH_(2)–NaAlH_(4).Moreover,the de/rehydrogenation 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 dehydrogenation,the CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample desorbed 2.6 wt.%H_(2),almost doubled compared to the amount of hydrogen desorbed from the undoped MgH_(2)–NaAlH_(4) *** activation energy obtained by the Kissinger analysis 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 catalytic function and be useful in ameliorating the de/rehydrogenation properties of the destabilized MgH_(2)–NaAlH_(4) system with the inclusion of CoTiO_(3).

关键词： Destabilize system Magnesium hydride Sodium alanate Hydrogen storage Additive.

Research progress on fluorescence sensing properties of metal-organic frameworks

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Journal of Molecular Science 2024年第2期40卷 107-114页

作者： zhou X. Chai y. Lu-Sun W. Fu z. Wang B. yuan G. School of Chemical and Blasting Engineering Anhui University of Science and Technology Huainan 232001 China

The metal-organic frameworks (MOFs) have the characteristics of high porosity and crystallinity, which also makes MOFs have the advantages of high sensitivity, high selectivity and high efficiency in the field of fluorescence sensing. It can detect the target substance efficiently and quickly, and has excellent anti-interference. Therefore, MOFs materials are also considered as ideal materials for fluorescence sensors. This paper introduces three common preparation methods of MOFs materials: hydrothermal/solvothermal method, mechanochemical method and microwave method. We focus on the application status of MOFs materials in the three fluorescence sensing fields of small molecules, metal cations and inorganic anions, as well as the shortcomings and improvement methods of MOFs materials in this application field. Finally, in view of the shortcomings of MOFs materials in the field of fluorescence sensing, such as poor stability, fluorescence quenching phenomenon susceptible to environmental interference, etc., it is proposed that more in-depth research should be carried out in the future in terms of anti-interference and reuse © 2024, Department of Chemistry, Northeast Normal University. All rights reserved.

关键词： detection fluorescence metal-organic framework sense

Mycorrhizal fungi mitigate nitrogen losses of an experimental grassland by facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： yangyang JIA Marcel G.A.VAN DER HEIJDEN Alain y.VALzANO-HELD Markus JOCHER Florian WALDER Postdoctoral Mobile Station of Ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China Research Group Plant-Soil Interactions AgroscopeZürich 8046Switzerland Research Group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and Microbial Biology University of ZürichZürich 8008Switzerland Research Group Soil Quality and Soil Use AgroscopeZürich 8046Switzerland

Nitrogen(N)is one of the most limited nutrients of terrestrial ecosystems,whose losses are prevented in tightly coupled cycles in finely tuned *** change-induced N enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial N *** mycorrhizal fungi(AMF)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AMF involvement in N cycling under global change is still ***,we simulated N enrichment by fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AMF and continuously monitored different N pathways over nine *** found that high N enrichment by fertilization decreased the relative abundance of legumes and the plant species dominating the plant community changed from grasses to forbs in the presence of AMF,based on aboveground *** presence of AMF always maintained plant N:phosphorus(P)ratios between 14 and 16,no matter how the soil N availability *** in plant N:P ratios due to the increased plant N and P uptake might thus be a primary pathway of AMF altering plant community ***,we constructed a comprehensive picture of AMF’s role in N cycling,highlighting that AMF reduced N losses primarily by mitigating N leaching,while N_(2)O emissions played a marginal *** mycorrhizal fungi reduced N_(2)O emissions directly through the promotion of N_(2)O-consuming *** underlying mechanism for reducing N leaching is mainly the AMF-mediated improved nutrient uptake and AMF-associated microbial *** results indicate that synergies between AMF and other soil microorganisms cannot be ignored in N cycling and that the integral role of AMF in N cycling terrestrial ecosystems can buffer the upcoming global changes.

关键词： N cycling N enrichment N uptake N:P ratio plant community structure symbiotic soil fungi