摘要：High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and *** studies on the deformation mech-anisms of HEAs can guide microstructure control and toughness design,which is vital for understanding and studying state-of-the-art structural *** X-ray and neutron diffraction are necessary techniques for materials science research,especially for in situ coupling of physical/chemical fields and for resolving macro/microcrystallographic information on ***,several re-searchers have applied synchrotron X-ray and neutron diffraction methods to study the deformation mechanisms,phase transformations,stress behaviors,and in situ processes of HEAs,such as variable-temperature,high-pressure,and hydrogenation *** this review,the principles and development of synchrotron X-ray and neutron diffraction are presented,and their applications in the deformation mechanisms of HEAs are *** factors that influence the deformation mechanisms of HEAs are also *** review fo-cuses on the microstructures and micromechanical behaviors during tension/compression or creep/fatigue deformation and the application of synchrotron X-ray and neutron diffraction methods to the characterization of dislocations,stacking faults,twins,phases,and intergrain/interphase stress *** on future developments of synchrotron X-ray and neutron diffraction and on research directions on the deformation mechanisms of novel metals are discussed.

摘要：高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSACs)进行了系统研究,通过轴向d-d轨道杂化提高了从SACs到BSACs的电催化硝酸盐还原反应(NO_(3)RR)的活性和选择性。考虑到可能的O端、N端、NO端和NO二聚体途径,计算结果显示,在单层SACs中,Ti-Pc和V-Pc分别具有优异的极限电位(U_(L)),分别为-0.24和-0.48V。形成能、溶解势以及从头算分子动力学结果表明,在反应条件下,这些催化剂非常稳定。在这些单层TM-Pc中,它们的d带能级和占据数受到d_(xz)/d^(yz)和p_(z)轨道杂化的影响。其轴向d_(z^(2))轨道的可用性通过形成d_(z^(2))-d_(z^(2))相互作用来进一步调整d带和反应性。在此基础上,以Ti-Pc和V-Pc为底物,通过形成轴向d-d轨道杂化来构建BSACs,为调节NO_(3)RR催化性能提供了一种独特的新途径。重要的是,我们发现d带中心(εd)、d_(xz)+d_(yz)轨道的占据数和U_(L)之间存在二维火山关系,用于描述它们的NO_(3)RR催化性能。最佳的BSACs应该同时具备适当的ε_(d)和d_(xz)+d_(yz)占用数。Ti-Mo和Ti-Ta被确定为出色的NO_(3)RR催化剂,其U_(L)均降低至-0.13 V。而d_(z^(2))-d_(z^(2))轨道之间的杂化则增强了双层金属之间的电荷转移和结构稳定性。缺乏相邻的金属位点将导致生成NO_(2)、NO和N_(2)的能垒较高,从而抑制副产物生成。最终,本研究揭示了在SACs和BSACs上对硝酸盐还原进行合理优化的方法,可为改进电催化剂的设计提供指导。

摘要：Oxygen(O_(2))-sensing matrices are promising tools for the live monitoring of extracellular O_(2) consumption levels in long-term cell *** this study,ratiometric O_(2)-sensing membranes were prepared by electrospinning,an easy,low-cost,scalable,and robust method for fabricating ***(ε-caprolactone)and poly(dimethyl)siloxane polymers were blended with tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)dichloride,which was used as the O_(2)-sensing probe,and rhodamine B isothiocyanate,which was used as the reference *** functionalized scaffolds were morphologically characterized by scanning electron microscopy,and their physicochemical profiles were obtained by Fourier transform infrared spectroscopy,thermogravimetric analysis,and water contact angle *** sensing capabilities were investigated by confocal laser scanning microscopy,performing photobleaching,reversibility,and calibration curve studies toward different dissolved O_(2)(DO)*** sensing nanofibers showed a high response to changes in DO concentrations in the physiological-pathological range from 0.5%to 20%and good stability under ratiometric *** addition,the sensing systems were highly biocompatible for cell growth promoting adhesiveness and growth of three cancer cell lines,namely metastatic melanoma cell line SK-MEL2,breast cancer cell line MCF-7,and pancreatic ductal adenocarcinoma cell line Panc-1,thus recreating a suitable biological environment in *** O_(2)-sensing biomaterials can potentially measure alterations in cell metabolism caused by changes in ambient O_(2)content during drug testing/validation and tissue regeneration processes.

摘要：过渡金属氧化物具有丰富的功能性,但其错综复杂的内部自由度对相图绘制和结构设计提出了挑战.本文中,我们引入了描述相图物理起源的轨道能级序(ELO),并通过对La_(0.67)Sr_(0.33)MnO_(3)(LSMO)氧化物的研究证明了其在相图预测中的有效性.结合DFT计算和实验,我们构建了氧含量和应变关联的LSMO相图,结果表明LSMO结构稳定性与ELO密切相关.据此发现了一种由ELO演化而产生的四倍氧有序相.最后,我们提出了描述轨道分裂程度的轨道弹性定律,阐明了ELO演化的起源,助力功能氧化物的设计.这项研究拓宽了材料科学领域的性能调控手段,并为从轨道角度预测相图提供了思路.

摘要：铂(Pt)是质子交换膜燃料电池(PEMFCs)阳极氢氧化反应(HOR)中最先进的电催化剂.然而,Pt催化剂对CO(工业低成本氢燃料中的杂质)极度敏感从而中毒,这会引起器件性能的急剧衰退,导致器件运行成本高.因此,提高Pt催化剂的CO耐受性对PEMFCs的商业化推广至关重要.在此,我们设计合成了一种独特的PtNiW@WO_(x)核壳纳米线来提高Pt基催化剂对CO的耐受能力.机理研究表明,表面无定形的WO_(x)壳层可以作为分子围栏,在动力学上阻碍CO扩散到达Pt位点.在热力学上,Ni和W元素合金化产生的电子效应可以使Pt的d带中心降低,减弱CO在Pt位点上的化学吸附.此外,亲氧W元素可以加速水的解离,提供更多OH活性物种,促进CO的氧化脱附.因此,在1000ppm CO/H_(2)条件下,所设计的PtNiW@WO_(x)核壳纳米线催化剂表现出优异的HOR抗CO中毒性能,在4000 s后仍能保持超过90%的HOR电流密度,超过了原始的PtNi纳米线和目前报道的绝大多数Pt基催化剂.

摘要：肿瘤微环境中的血管生成是肿瘤细胞对放化疗不敏感的主要原因.在本项研究中,我们设计了一种微环境响应型的纳米颗粒,利用ZrMOF的分解产物抑制肿瘤细胞中的PI3K/AKT/mTOR/VEGF通路,从而克服A549R细胞对顺铂的耐药性.我们将顺铂包裹在Zr-MOF中,并在表面修饰BSA,形成了CDDP@Zr-MOF-BSA纳米复合体,该复合体在肿瘤微环境中有良好的响应性,有助于在肿瘤区域蓄积,展现出卓越的血管生成抑制能力,并能明显降低药物的外排.此外,CDDP@Zr-MOFBSA能显著抑制多药耐药相关蛋白1(MRP1)的表达,从而逆转A549R细胞的耐药性.总体而言,CDDP@Zr-MOF-BSA对A549R有细胞毒性,能抑制肿瘤微环境中的血管生成,最终有效提高顺铂耐药肿瘤的治疗效果.CDDP@Zr-MOF-BSA为放化疗治疗耐药肿瘤提供了一种多功能协同的方法.

摘要：聚合物基固态电解质得益于其易加工性,最有希望应用于下一代固态锂金属电池.目前,聚合物基态电解质的离子电导率提升策略多为加入导锂陶瓷以构建离子传输通道,其提升程度有限.电场在锂离子输运过程中存在重要影响,目前研究中有关电场对锂离子传输的影响机制尚不明确.本文将兼具高离子电导率和高介电常数的铌酸锂嵌入聚偏氟乙烯基体中,设计了一种新型复合固态电解质.铌酸锂颗粒有效调节电解质内部电场结构,增强了离子输运方向电场强度,实现了离子电导率的大幅提升(7.39×10^(-4)S cm^(-1),25℃).该电解质匹配高镍正极和锂金属负极的固态电池可稳定循环1000次以上,容量保持率为72%.该研究为设计下一代固态锂电池用高离子电导复合固态电解质提供了新的策略.

摘要：In this paper,we find the information loss for QCD matter in AdS black holes at LHC by extending the Gottesman and Preskill methode to AdS black *** calculate the information transformation from the collapsing matter to the state of outgoing Hawking radiation for both quarks and *** is noticed that for finite values of quark and gluon energies,information from all emission processes experiences some degrees of *** explanation for this feature will be presented in this paper.

摘要：We give a brief introduction to the AdS/CFT correspondence and its application to QCD physics,especiallyits application in the study of quark-gluon-plasma (QGP)formed in the relativistic heavy ion collision (RHIC).Thisreview is based on the talks given in several schools and programs for the phenomenologists working on nuclear physicsand particle physics.

摘要：We review a recent work on masses of mesons and nucleons within a hard wall model of holographic QCD in a unified *** order to treat meson and nucleon properties on the same footing,we introduced the same infrared （IR） cut for both *** framework of present approach,the best fit to the experimental data is achieved introducing the anomalous dimension for baryons.