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Multi-walled carbon nanotubes covalently functionalized by axially coordinated metal-porphyrins： Facile syntheses and temporally dependent optical performance

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Nano Research 2016年第2期9卷 458-472页

作者： Aijian Wang.Jing.ao Song.Zhipeng.Huang.Ying.in Song.Wang.Yu Huanli Dong.Wenping.Hu Marie P. Cifuentes mark g. humphrey Long.Zhang.Jianda Shao Chi Zhang China-Australia Joint Research Center for Functional Molecular Materials Scientific Research Academy Jiangsu UniversityZhenjiang 212013 China China-Australia Joint Research Center for Functional Molecular Materials School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China Key Laboratory of Materials for Hig.-Power Laser Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China School of Physical Science and Technolog. Soochow University Suzhou 215006 China Key Laboratory of Org.nic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Research School of Chemistry Australian National University Canberra ACT2601 Australia

Axially coordinated metal-porphyrin-functionalized multi-walled carbon nanotube （MWCNT） nanohybrids were prepared via two different synthetic approaches （a one-pot 1,3-dipolar cycloaddition reaction and a stepwise approach that involved 1,3-dipolar cycloaddition followed by nucleophilic substitution）, and characterized throug. spectroscopic techniques. Attachment of the tin porphyrins to the surface of the MWCNTs sig.ificantly improves their solubility and ease of processing. These axially coordinated （5,10,15,20-tetraphenylporphyrinato）tin（Ⅳ）（SnTPP）- MWCNTs exhibit sig.ificant fluorescence quenching. The third-order nonlinear optical properties of the resultant nanohybrids were studied by using.the Z-scan technique at 532 nm with both nanosecond and picosecond laser pulses. The results show that the nanohybrids exhibit sig.ificant reverse saturable absorption or saturable absorption when nanosecond or picosecond pulses, respectively, are employed. Improvement in the nanosecond reg.me nonlinear absorption is observed on proceeding.to the nanohybrids and is ascribed to a combination of the outstanding.properties of MWCNTs and the chemically attached metal-porphyrins.

关键词： metal-porphyrin axially coordinated multi-walled carbon nanotubes facile syntheses optical performance cycloaddition

多样化二氧化碳去除方法下交通部门使用氢能的潜在效益和权衡

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Science Bulletin 2024年第1期69卷 34-39页

作者：刘海峰 Jeffrey Dankwa Ampah Sandylove Afrane humphrey Adun 金超尧命发 State Key Laboratory of Eng.nes Tianjin UniversityTianjin 300072China School of Environmental Science and Eng.neering Tianjin UniversityTianjin 300072China Energ. Systems Eng.neering.Department Cyprus International UniversityHaspolat-Lefkosa Mersin 10Turkey

Climate chang. remains arg.ably one of the most important issues facing.the world in the 21st *** to the Paris Ag.eement,the world should strive to limit g.obal mean temperature chang. by 2100 to below 1.5-2℃above pre-industrial levels[1].To achieve this g.al,g.obal net carbon dioxide(CO_(2))emissions should reach zero no later than 2050 for the realization of the1.5℃targ.t and 2070 for the 2℃targ.t,respectively[2].Since the introduction of this g.obal commitment,several mitig.tion options have been proposed to achieve the climate g.al.

关键词：潜在效益 g.obal climate

Effect of Lateritic Stone Ag.reg.te and Coconut Husk Fiber on the Properties of Concrete

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Open Journal of Civil Eng.neering 2024年第2期14卷 240-257页

作者： Edmund Borbi humphrey Danso Emmanuel Appiah-Kubi Department of Construction Technolog. and Manag.ment Education Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development Kumasi Ghana Department of Architecture and Civil Eng.neering Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development Kumasi Ghana

Natural stone ag.reg.te forms the bulk volume of concrete and has contributed to the increased cost of concrete production. This has led to the search for alternate ag.reg.tes such as lateritic stone for concrete production. This paper investig.tes the eng.neering.properties of concrete produced with lateritic ag.reg.te (LA) as the coarse ag.reg.te replacement and coconut husk fibre (CHF) as reinforcement. Natural stone ag.reg.te was replaced by LA at 0%, 10%, 20%, 30%, 40%, and 50%, with 0.25% constant CHF by weig.t. A mix proportion of 1:1.5:3 with a water-cement ratio of 0.6 was used for producing.concrete. A total of 162 specimens (90 cubes and 72 beams) were prepared and tested at the 7, 14, 21, and 28 days of curing. The hig.est compressive streng.h was 43.36 N/mm2 (10% LA replacement) as compared to the control of 41.51 N/mm2. The 10% LA replacement obtained the hig.est flexural streng.h of 5.35 N/mm2 as compared with the 5.29 N/mm2 for the control. The water absorption of the concrete increased from 2.8% (control) to 3.57% (50% replacement LA). Scanning.electron microscopy (SEM) revealed micro g.ps between CHF and LA concrete. The study, therefore, concludes that the use of LA and CHF positively influenced the streng.h properties of concrete. 10% LA replacement of coarse ag.reg.te and 0.25% CHF is recommended to practitioners for use.

关键词： Concrete Coarse Ag.reg.te Compressive Streng.h Flexural Streng.h Natural Stone Ag.reg.te SEM

Covalent edg.-functionalization of g.aphene oxide with porphyrins for hig.ly efficient photoinduced electron/energ. transfer and enhanced nonlinear optical performance

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Nano Research 2023年第1期16卷 25-32页

作者： Lulu Fu mark g.humphrey Chi Zhang China-Australia Joint Research Center for Functional Molecular Materials School of Chemical Science and EngineeringTongji UniversityShanghai 200092China School of Chemical and Material Eng.neering Jiangnan UniversityWuxi 214122China Research School of Chemistry Australian National UniversityCanberraACT 2601Australia

Covalent modification of g.aphene oxide(g.)with functional chromophores plays an important role in constructing.various kinds of advanced optoelectronic materials for applications in molecular diag.osis,lig.t-harvesting.photodynamic therapy,and optical ***,a new approach to functionalizing.g. with meso-substituted formylporphyrins at g.’s edg. sites via imidazole condensation is developed,which affords a novel g.-imi-Por nanohybrid covalently-linked by imidazole ring. between two *** structure of the g.-imi-Por nanohybrid was thoroug.ly characterized by scanning.electron microscopy(SEM),attenuated total reflectance-Fourier transform infrared(ATR-FTIR),Raman,and X-ray photoelectron spectroscopy(XPS).The red-shifted steady-state absorption,95%quenched fluorescence,and larg.ly enhanced nonlinear optical(NLO)properties throug. Z-scan studies at lower input energ.es demonstrate that this g.-imi-Por nanohybrid exhibits a more effective photoinduced energ./electron transfer between the intrahybrid two components and can be flexibly applied as an optical limiter *** covalent edg.-functionalization approach provides a new paradig. for constructing.various edg.-expanding.g. nanohybrids with an efficient energ./electron transfer process and improved nonlinear optical effects,which would draw inspiration for eng.neering.more adaptable optoelectronic devices.

关键词： covalent edg.-functionalization nonlinear optics g.aphene oxide porphyrin nanohybrid

多样化二氧化碳去除方法下交通部门使用氢能的潜在效益和权衡（英文）

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Science Bulletin 2024年第1期 34-39页

作者：刘海峰 Jeffrey Dankwa Ampah Sandylove Afrane humphrey Adun 金超尧命发 State Key Laboratory of Eng.nes Tianjin University School of Environmental Science and Eng.neering Tianjin University Energ. Systems Eng.neering.Department Cyprus International University

Climate chang. remains arg.ably one of the most important issues facing.the world in the 21st *** to the Paris Ag.eement,the world should strive to limit g.obal mean temperature chang. by 2100 to below 1.5-2℃above pre-industrial levels[1].To achieve this g.al,g.obal net carbon dioxide (CO2) emissions should reach zero no later than 2050 for the realization of the1.5℃targ.t and 2070 for the 2℃targ.t,respectively [2].Since the introduction of this g.obal commitment,several mitig.tion options have been proposed to achieve the climate ***,

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Physicochemical Analysis of Locally Made Yog.urt (Kossam) Commercialised in the City of Douala-Cameroon

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Open Journal of Physical Chemistry 2024年第3期14卷 49-60页

作者： Sidoine Sadjeu Tchakouteu Kang.Costly Eha-Kang.François Siewe humphrey Ng.le Jordan Wabo Blandine Penn Sandra Fokam Thelma Njuikui Yimeli Rodiah Fresnell Tcheuffa Bertin Sone Enone Department of Biomedical and Technical Science Higher Institute of Applied Sciences/University Institute of the Gulf of Guinea of Douala Douala Cameroon Department of Pharmaceutical Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Pharmaco-Chemistry and Natural Substances Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon

Yog.rt is a traditional dairy product well known in all the reg.ons of the world. In Cameroon, the most popularly known type is “kossam” also called curdled milk. Kossam is a set of milk based beverag. from northern Cameroon presenting.g.eat symbolic, economic and social values for local population [1]. 150 Kossam samples were collected from neig.borhoods of PK8, Bonamoussadi, Nyalla, cite des palmier, Deido and Bedi community and later on reconstituted into 50 different samples of 350 mL, each containing.1/3 of 3 individual samples. They were analyzed for their physiochemical properties such as: PH, titratable acidity, density, brix and dry matter using.most at times the standard Association of Official Analytical Chemists (AOAC) methods with slig.t modifications and results compared to a licensed brand sold in the Cameroonian market. The results of the study showed that, the physico-chemical properties of the locally made yog.rts were different within the different samples. Analysis of variance revealed a sig.ificant difference in the levels of the parameters analyzed in the different yog.rt samples (p −1 Kg.L), Brix (8˚ - 24˚B), Dornic (23˚ - 160˚D). others contents per 100 g.fresh matter are as follows: dry matter (averag. mean of 16.54%). Hence, the sig.ificant variations in the physico-chemical properties of kossam are a call for concern since as it impacts on the health of the population consuming.this product.

关键词： Kossam Physicochemical Analysis Brix Titratable Acidity

Hybrids of g.ld nanoparticles and olig.(p-phenyleneethynylene)s end-functionalized with alkynylruthenium g.oups:Outstanding.two-photon absorption in the second biolog.cal window

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Nano Research 2020年第10期13卷 2755-2762页

作者： Cristóbal Quintana Mahbod Morshedi Jun Du Joseph P.L.Morrall Jan K.Zaręba Marek Samoc Marie P.Cifuentes mark g.humphrey I Research School of Chemistry Australian National UnriversityCanberraACT 2601Australia Advanced Materials Eng.neering.and Modelling.g.oup Wroclaw University of Science and TechnologyWroclaw 50370Poland

Olig.(p-phenyleneethynylene)s(OPEs)end-capped with(alkynyl)bis(diphosphine)ruthenium and thiol/thiolate g.oups stabilize ca.2 nm diameter g.ld nanoparticles(AuNPs).The morpholog.,elemental composition and stability of the resultant org.nometallic OPE/AuNP hybrid materials have been defined using.a combination of molecular-and nano-material chacterization *** hybrids display long.term stability in solution(more than a month),g.od solubility in org.nic solvents,reversible rutheniumcentered oxidation,and transparency beyond 800 nm,and possess very strong.nonlinear absorption activity at the first biolog.cal window,and unprecedented two-photon absorption activity in the second biolog.cal window(σ2 up to 38,000 g. at 1,050 nm).

关键词： g.ld nanoparticles inorg.nic materials metal alkynyl complexes nonlinear optics org.nometallics

Strong.near-infrared and ultrafast femtosecond nonlinearities of a covalently-linked triply-fused porphyrin dimer-SWCNT nanohybrid

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Nano Research 2022年第2期15卷 1355-1365页

作者： Lulu Fu Jun Ye Hui Li Zhipeng.Huang.mark g.1} Chi Zhang China-Australia Joint Research Center for Functional Molecular Materials School of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China China-Australia Joint Research Center for Functional Molecular Materials School of Chemical Science and Engineerinz Ton^ii UniversityShanghai 200092China Research School of Chemistry Australian National UniversityCanberraACT 2601Australia

Functional materials displaying.larg. ultrafast third-order optical nonlinearities across a wide spectral reg.on and broad temporal domain are required for all-optical sig.al *** desirable is nonlinear optical(NLO)activity at near-infrared(NIR)waveleng.hs with femtosecond *** the first triply-fused porphyrin dimer(TFP)-functionalized sing.e-walled carbon nanotube(SWCNT)nanohybrid was successfully constructed by covalently g.afting.TFPs onto *** results of Z-scan techniques demonstrate that the newly obtained TFP-SWCNT nanohybrid was found with a strong.NLO performance under both nanosecond and femtosecond *** the nanosecond reg.me,an enhancement in optical limiting.OL)of the TFP-SWCNT nanohybrid is seen at 532 nm when compared with the performance of porphyrin monomer-functionalized SWCNT nanohybrid *** femtosecond irradiation,the TFP-SWCNT nanohybrid exhibits a particularly strong.OL effect with a g.ant two-photon absorption(TPA)cross section value(ca.15,500 g.)at 800 nm pulses that mainly stems from intense TPA of TFP,in sharp contrast to the Por-SWCNT nanohybrid which exhibits only saturable absorption under identical *** results demonstrate that the newly-developed TFP-SWCNT nanohybrid is a very promising.OL candidate for practical applications across wide spectral and temporal domains,and that covalently functionalizing.carbon-based materials with triply-fused chromophores may be a useful approach to eng.neering.adaptable photonic devices with broad-rang.ng.NLO activity.

关键词： triply-fused porphyrin dimer carbon nanotube near-infrared femtosecond nonlinear optical materials

Accretion/jet activity and narrow [O III] kinematics in young.radio g.laxies

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 235-239页

作者： Andrew humphrey Korean Astronomy and Space Science Institute Daejeon 305348 Korea Instituto Nacional de Astrofisica Optica y Electronica(INAOE)Aptdo.Postal 51 y 21672000 PueblaPue.Mexico

We estimate black hole masses and Edenton ratios for a sample of 81 young.radio g.laxies,which includes 42 compact steep-spectrum(CSS) and 39 g.g.hertz-peaked spectrum(g.S) *** find that the averag. black hole(BH) mass of these young.radio g.laxies is〈log.Mbh〉-8.3,which is less than that of radio loud QSOs and low redshift radio g.laxies(〈 log.Mbh〉-9.0).The CSS/g.S sources have relatively hig. Edding.on ratios,with an averag. value of〈log.Lbol/LEdd〉=-0.75,which are similar to those of narrow line Seyfert 1 g.laxies(NLS1s).This sug.ests that young.radio g.laxies may not only be in the early stag.s of their radio activity,but also in the early stag. of their accretion *** find that the young.radio g.laxies,as a class,systematically deviate from the Mbh-σ relation defined by nearby inactive g.laxies,when using.σ[O III] as a surrog.te for stellar velocity dispersion σ.We also find that the deviation of the [O III] line width,Δσ =σ[O III]-σ[pred],is correlated with the Edding.on ratio;sources with Lbol/LEdd-1 have the larg.st deviations,which are similar to those of radio quiet QSOs/NLS1s(i.e.,sources in which the radio jets are absent or weak),and where σ[pred] is calculated from the Tremaine et *** using.our estimated BH masses.A similar result has been obtained for 9 linear radio Seyfert *** the basis of these results,we sug.est that,in addition to the possible jet-g.s interactions,accretion activities may also play an important role in shaping.the kinematics of the narrow [O III] line in young.radio g.laxies.

关键词： accretion accretion discs-ISM:jets and outflows-radio continuum:g.laxies-quasars:emission lines