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A new class of crystalline X-ray induced photochromic materials assembled from anion-directed folding of a flexible cation

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Chinese Chemical Letters 2024年第8期35卷 554-557页

作者： Hong-Jin Liao Zhu Zhuo Qing Li Yoshihito Shiota jonathan p.hill Katsuhiko Ariga Zi-Xiu Lu Lu-Yao Liu Zi-Ang Nan Wei Wang You-Gui Huang CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China Xiamen Key Laboratory of Rare Earth photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen 361021China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China Institute for Materials Chemistry and Engineering Kyushu UniversityFukuoka 819-0395Japan World premier International(WpI)Center for Materials Nanoarchitectonics(MANA) National Institute for Materials Science(NIMS)Ibaraki 305-0044Japan

Electron-deficient viologens are widely used as ligands or structure-directing agents(SDAs)to synthesize crystalline X-ray induced photochromic ***,a new rational strategy of anion-directed fold-ing a flexible cation(H_(2)imb)^(2+)((H_(2)imb)^(2+)=di-protonated 2,3-bis(imidazolin-2-yl)-2,3-dimethylbutane)has been ***-donating Cl−and(ZnCl4)2−are used to direct folding a flexible electron-deficient(H_(2)imb)^(2+)*** complexes(H_(2)imb)(NO_(3))2(1),(H_(2)imb)Cl2·H_(2)O(2),and(H_(2)imb)ZnCl4(3)have been synthesized in which(H_(2)imb)^(2+)crystallize in an anti-conformation,88.8°-gauche,and 51.8°-gauche,*** contrary to X-ray silent complex 1,X-ray induced photochromism has been achieved in both complex 2 and *** intermolecular charge-transfer mechanism has been elucidated and the anion directed folding of(H_(2)imb)^(2+)has been validated to be critical to yield colored long-lived charge-separated states.

关键词： Supramolecular photochromic X-ray induced Anion-directed folding Electron-deficient viologens

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Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 28-40页

作者： Daniel T.payne Mandeep KChahal Vaclav Brezina Whitney A.Webre Katsuhiko Ariga Francis D’Souza Jan Labuta jonathan p.hill WpI Center for Materials Nanoarchitectonics National Institute for Materials ScienceIbaraki 305-0044Japan Department of Macromolecular physics Faculty of Mathematics and PhysicsCharles University18000 PragueCzech Republic Department of Chemistry University of North TexasDentonTX 76203USA Department of Advanced Materials Science Graduate School of Frontier SciencesThe University of TokyoChiba 277-8561Japan

Chiral 1,1’-binaphthyl-linked diporphyrin‘tweezers’(R)-1/(S)-1 and the corresponding zinc(II)complexes(R)-2/(S)-2 were prepared as chiral host molecules,and their utility for chiral analyses(especially enantiomeric excess(ee)determinations)were ***(1-n-dodecyl)porphyrins were used for the first time as the interacting *** capabilities of the diporphyrin tweezers were investigated by titrations with(R,R)-and(S,S)-cyclohexane-1,2-diamine(CHDA).The host molecules could be used as multichannel probes of ee by using UVvis,circular dichroism(CD),fluorescence emission and 1H nuclear magnetic resonance(1 H-NMR)*** configurations could also be differentiated using CD or 1HNMR *** three optical techniques give good resolution of ee with reasonable sensitivity considering the low concentrations used(ca.10^-6 mol·L^-1).The ee determination of CHDA enantiomers using NMR spectroscopy is also possible because of the reasonably well separated resonances in the case of(R,R)-and(S,S)-***-metallated(R)-1/(S)-1 hosts could not be used to detect chiral information in a strongly acidic chiral *** work demonstrates the utility of 1,1’-binapthyllinked chiral hosts for chiral analysis of ditopically interacting enantiomers.

关键词： porphyrin dimer chirality enantiomeric excess CD fluorescence

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Molecular rotor based on an oxidized resorcinarene

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Organic Chemistry Frontiers 2022年第1期9卷 39-50页

作者： Daniel T.payne Jan Labuta Zdeněk Futera Václav Březina Lenka Hanyková Mandeep K.Chahal jonathan p.hill International Center for Materials Nanoarchitectonics National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan bInternational Center for Young Scientists National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan Institute of physics Faculty of ScienceUniversity of South BohemiaBranišovská1760ČeskéBudějovice 37005Czech Republic Faculty of Mathematics and physics Charles UniversityV Holešovičkách 218000 Prague 8Czech Republic

Molecular rotors are an important class of dynamic molecules which have been studied not only for their possible uses as components of molecular machines but also because of potential applications as probes of local viscosity in biological media,especially self-assembled *** the former,factors affecting rotational motility are critical while for the latter the rotor activity must be complexed with an output signal(often fluorescence)for reporting of local *** single stator-double rotor activity of an oxidized resorcinarene(fuchsonarene)macrocycle containing unsaturated hemiquinonoid groups at its meso positions was *** contain two hemiquinonoid substituents at diagonally-opposed meso-positions with two electron rich phenol groups at the remaining meso-positions between the hemiquinonoid *** meso-substituents are in proximity at one side of the resorcinarene macrocycle(so-called rccc-type isomer)with rotational activity of the phenol *** rates of the phenol moieties can be controlled by varying temperature,solvent polarity and acidity of the medium of study with rotation being thermally activated in neutral and acidic media and tunable in the range from 2 s^(−1) to 20000 s^(−1).Experimental and computational data indicate that rotation of the mobile phenol meso-substituents is remotely affected by interactions with acidic solvents at the carbonyl CvO groups of macrocyclic acetyloxy groups,which occurs with the emergence of a lower energy electronic absorption band whose intensity is correlated with both the acidity of the medium and the rotation rate of the phenol ***-dependent DFT calculations suggest that the low energy band is due to a molecular conformational adjustment affecting electronic conjugation caused by strong interaction of macrocyclic acetyloxy carbonyl groups with the acid *** work presents a molecular mechanical model for estimating solution acidity a

关键词： substituent rotation oxidized

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功能光电分子的表面分散与STM研究

功能光电分子的表面分散与STM研究

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中国真空学会2012学术年会

作者：邝艳敏耿锋张尧朱三娥 André Gourdon jonathan p.hill 王官武董振超中国科学技术大学微尺度物质科学国家实验室

二萘嵌苯分子由于具有高荧光效率等优良的光电性质,在电子和光电元件中有着广泛的应用。化学修饰的二萘嵌苯分子衍生物由于具有新的光电特性在纳米光电子学和纳米电子学领域也得到了广泛的研究。在本文中,我们在超高真空环境下利用闪热...

二萘嵌苯分子由于具有高荧光效率等优良的光电性质,在电子和光电元件中有着广泛的应用。化学修饰的二萘嵌苯分子衍生物由于具有新的光电特性在纳米光电子学和纳米电子学领域也得到了广泛的研究。在本文中,我们在超高真空环境下利用闪热脱吸附方法5将具有四脚架结构的二萘嵌苯分子衍生物沉积到金属衬底上,并利用STM对吸附的分子进

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Deformable microlaser force sensing

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Light(Science & Applications) 2024年第6期13卷 1196-1209页

作者： Eleni Dalaka Joseph Shill jonathan H.H.Booth Anna popczyk Stefan R.pulver Malte C.Gather Marcel Schubert Centre of Biophotonics SUPASchool of Physics and AstronomyUniversity of St AndrewsNorth HaughSt AndrewsUK Humboldt Centre for Nano-and Biophotonics Department of ChemistryUniversity of CologneKölnGermany School of psychology and Neuroscience University of St AndrewsSt Mary’s QuadSouth StreetSt AndrewsUK Institute for Bioengineering of Catalonia BarcelonaSpain

Mechanical forces are key regulators of cellular behavior and function,affecting many fundamental biological processes such as cell migration,embryogenesis,immunological responses,and pathological *** force sensors and imaging techniques have been developed to quantify these otherwise invisible forces in single cells and in ***,current techniques rely heavily on high-resolution microscopy and do not allow interrogation of optically dense tissue,reducing their application to 2D cell cultures and highly transparent biological ***,we introduce DEFORM,deformable microlaser force sensing,a spectroscopic technique that detects sub-nanonewton forces with unprecedented spatio-temporal *** is based on the spectral analysis of laser emission from dye-doped oil microdroplets and uses the force-induced lifting of laser mode degeneracy in these droplets to detect nanometer *** validation by atomic force microscopy and development of a model that links changes in laser spectrum to applied force,DEFORM is used to measure forces in 3D and at depths of hundreds of microns within tumor spheroids and late-stage Drosophila *** furthermore show continuous force sensing with single-cell spatial and millisecond temporal resolution,thus paving the way for non-invasive studies of biomechanical forces in advanced stages of embryogenesis,tissue remodeling,and tumor invasion.

关键词： invasion otherwise hundreds

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Treatment of Helicobacter pylori with potassium competitive acid blockers:A systematic review and meta-analysis

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World Journal of Gastroenterology 2024年第9期30卷 1213-1223页

作者： Joseph Edwin Kanu jonathan Soldera post Graduate program at Acute Medicine and Gastroenterology University of South WalesCardiff CF371DLUnited Kingdom

BACKGROUND Helicobacter pylori(***)infects over half the global population,causing gastrointestinal diseases like dyspepsia,gastritis,duodenitis,peptic ulcers,GMALT lymphoma,and gastric *** *** is crucial for treating and preventing these *** conventional proton pump inhibitor(ppI)-based triple therapy is effective,there’s growing interest in longer acid suppression *** competitive acid blocker(p-CAB)triple and dual therapy are new regimens for *** *** used in Asian populations,vonoprazan(VpZ)has been recently Food and Drug Administration-approved for *** *** To assess the efficacy of regimens containing p-CABs in eradicating *** *** This study,following pRISMA 2020 guidelines,conducted a systematic review and meta-analysis by searching MEDLINE and Scopus libraries for randomized clinical trials(RCTs)or observational studies with the following command:[("Helicobacter pylori"OR"H pylori")AND("Treatment"OR"Therapy"OR"Eradication")AND("Vonaprazan"OR"potassium-Competitive Acid Blocker"OR"p-CAB"OR"pCAB"OR"Revaprazan"OR"Linaprazan"OR"Soraprazan"OR"Tegoprazan")].Studies comparing the efficacy of p-CABs-based treatment to classical ppIs in eradicating *** were *** criteria included case reports,case series,unpublished trials,or conference *** variables encompassed age,diagnosis method,sample sizes,study duration,intervention and control,and *** eradication method were gathered by two independent ***-analysis was performed in R software,and forest plots were *** A total of 256 references were initially retrieved through the search ***,fifteen studies(7 RCTs,7 retrospective observational studies,and 1 comparative unique study)were included,comparing p-CAB triple therapy to ppI triple *** intention-to-treat analysis involved 8049 patients,with 4471 in the p-CAB intervention g

关键词： Helicobacter pylori infection potassium competitive acid blockers proton pump inhibitors Vonoprazan Amoxicillin

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Formadinium Cation Doping Stabilized Ultra-deep-blue Lead Halide perovskite Nanocrystal Light-emitting Diodes

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Chemical Research in Chinese Universities 2024年第3期40卷 556-560页

作者： pui Kei KO jonathan E.HALpERT Department of Chemistry The Hong Kong University of Science and TechnologyKowloonHong Kong 999077P.R.China

The halide migration effect in mixed-halide lead-based perovskite is a serious problem hindering the development of its display *** this study,we have successfully addressed this issue by reporting formadinium(FA)doped mixed-halide perovskite nanocrystals(NCs)with ultra-deep-blue emission of 450 nm,narrow bandwidth of 16 nm,and a high photoluminescence quantum yield(pLQY)of 66%.The perovskite nanocrystal light-emitting diodes(NC-LEDs)using this nanocrystal as an active layer achieved a maximum external quantum efficiency(EQE)of 0.32%,30-fold improved compared to that of pristine and stable electroluminescence(EL)spectra at 450 nm under a 4.9–8.0 V *** findings demonstrate the potential of our approach in developing stable and efficient deep blue perovskite NC-LEDs.

关键词： Halide perovskite Light-emitting diode Deep-blue

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Geochemical elements in suspended particulate matter of Ensenada de La paz Lagoon,Baja California peninsula,Mexico:Sources,distribution,mass balance and ecotoxicological risks

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Journal of Environmental Sciences 2024年第2期136卷 422-436页

作者： Sandra Soledad Morales-García pilar de Acacia pérez-Escamilla Suresh Babu Sujitha pichaimani Godwyn-paulson Andrés Felipe Zuniga-Cabezas Muthuswamy ponniah jonathan Instituto politécnico Nacional(IpN) Centro Mexicano para la Producción más Limpia(CMPL)Av.Acueducto s/nCol.Barrio la Laguna TicománDel Gustavo A.MaderoC.P.07340Ciudad de MéxicoMexico Instituto politécnico Nacional(IpN) Escuela Superior de Ingeniería y Arquitectura(ESIA)Unidad Ticomán***án 600Delg.Gustavo A.MaderoC.P.07340Ciudad de México(CDMX)Mexico Instituto politécnico Nacional(IpN) Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo(CIIEMAD)Calle 30 de Junio de 1520Barrio la Laguna TicománDel.Gustavo A.MaderoC.P.07340Ciudad de MéxicoMéxico

The present study aimed to evaluate multi-element concentrations(Al,As,Ca,Cd,Co,Cr,Cu,Fe,Mg,Mn,Mo,Ni,pb,Sr)in suspended particulate material(SpM)collected from Ensenada de La paz(ELp)lagoon,Baja California Sur,Mexico in two different periods(September and May)to comprehend their origin,geochemical behavior,mass transfer and associated ecotoxicological *** 24 hr variation coefficient of volumetric SpM levels were found to be 51.7%in September and 40.5%in May,signifying the effects of oceanic *** calculated enrichment factor(EF)values for all the studied elements were of higher magnitude because of the high surface area and oxide nature of SpM,and in this study,Mo had the highest EF of 46.77 probably due to its origin from continental *** the ecotoxicological perspective,the integrated toxic risk index revealed low toxic risk to the benthic ***,the mean-ERM-Quotient calculated using the particulate concentrations of As,Cd,Cr,Cu,Ni,pb indicated 9%probability of toxicity to *** comprehensive geochemical and ecotoxicological assessment of particulate metal concentrations in the ELp lagoon signify low to moderate contamination.

关键词： Suspended particulate material Heavy metals Risk assessment Mass transfer Ensenada de La paz

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Mixed iridium-nickel oxides supported on antimony-doped tin oxide as highly efficient and stable acidic oxygen evolution catalysts

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Materials Futures 2024年第1期3卷 165-180页

作者： jonathan Ruiz Esquius Alec p LaGrow Haiyan Jin Zhipeng Yu Ana Araujo Rita Marques Adélio Mendes Lifeng Liu Clean Energy Cluster International Iberian Nanotechnology LaboratoryAv.Mestre JoséVeigaBraga 4715-330Portugal Carbon Science and Technology Institute INCAR-CSICFrancisco Pintado Fe 26Oviedo 33011Spain Scientific Imaging Section Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0412Japan Songshan Lake Materials Laboratory Dongguan 523808People’s Republic of China Laboratory for process Engineering EnvironmentBiotechnology and EnergyFaculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal Associate Laboratory in Chemical Engineering Faculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal.

proton exchange membrane(pEM)water electrolysis represents a promising technology for green hydrogen production,but its widespread deployment is greatly hindered by the indispensable usage of platinum group metal catalysts,especially iridium(Ir)based materials for the energy-demanding oxygen evolution reaction(OER).Herein,we report a new sequential precipitation approach to the synthesis of mixed Ir-nickel(Ni)oxy-hydroxide supported on antimony-doped tin oxide(ATO)nanoparticles(IrNiyO_(x)/ATO,20 wt.%(Ir+Ni),y=0,1,2,and 3),aiming to reduce the utilisation of scarce and precious Ir while maintaining its good acidic OER *** tested in strongly acidic electrolyte(0.1 M HClO_(4)),the optimised IrNi1Ox/ATO shows a mass activity of 1.0 mAµgIr^(−1) and a large turnover frequency of 123 s^(−1) at an overpotential of 350 mV,as well as a comparatively small Tafel slope of 50 mV dec^(−1),better than the IrOx/ATO control,particularly with a markedly reduced Ir loading of only 19.7µgIr cm^(−2).Importantly,IrNi1O_(x)/ATO also exhibits substantially better catalytic stability than other reference catalysts,able to continuously catalyse acidic OER at 10 mA cm^(−2) for 15 h without obvious *** in-situ synchrotron-based x-ray absorption spectroscopy confirmed that the Ir^(3+)/Ir^(4+)species are the active sites for the acidic ***,the performance of IrNi1Ox/ATO was also preliminarily evaluated in a membrane electrode assembly,which shows better activity and stability than other reference *** IrNi1Ox/ATO reported in this work is a promising alternative to commercial IrO_(2) based catalysts for pEM electrolysis.

关键词： mixed oxides oxygen evolution reaction polymer electrolyte membrane antimony doped tin oxide membrane electrode assembly

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Local Adaptive Gradient Variance Attack for Deep Fake Fingerprint Detection

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Computers, Materials & Continua 2024年第1期78卷 899-914页

作者： Chengsheng Yuan Baojie Cui Zhili Zhou Xinting Li Qingming jonathan Wu Engineering Research Center of Digital Forensics Ministry of EducationNanjing University of Information Science and TechnologyNanjing210044China School of Computer Science Nanjing University of Information Science and TechnologyNanjing210044China Institute of Artificial Intelligence and Blockchain Guangzhou UniversityGuangzhou510006China School of International Relations National University of Defense TechnologyNanjing210039China Department of Electrical and Computer Engineering University of WindsorWindsorN9B 3P4Canada

In recent years,deep learning has been the mainstream technology for fingerprint liveness detection(FLD)tasks because of its remarkable ***,recent studies have shown that these deep fake fingerprint detection(DFFD)models are not resistant to attacks by adversarial examples,which are generated by the introduction of subtle perturbations in the fingerprint image,allowing the model to make fake *** of the existing adversarial example generation methods are based on gradient optimization,which is easy to fall into local optimal,resulting in poor transferability of adversarial *** addition,the perturbation added to the blank area of the fingerprint image is easily perceived by the human eye,leading to poor visual *** response to the above challenges,this paper proposes a novel adversarial attack method based on local adaptive gradient variance for *** ridge texture area within the fingerprint image has been identified and designated as the region for perturbation ***,the images are fed into the targeted white-box model,and the gradient direction is optimized to compute gradient ***,an adaptive parameter search method is proposed using stochastic gradient ascent to explore the parameter values during adversarial example generation,aiming to maximize adversarial attack *** results on two publicly available fingerprint datasets show that ourmethod achieves higher attack transferability and robustness than existing methods,and the perturbation is harder to perceive.

关键词： FLD adversarial attacks adversarial examples gradient optimization transferability

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