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感觉世界—感觉和知觉导论

感觉世界—感觉和知觉导论

Effects of varying Alx moles on structure and luminescence properties of ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)nanophosphors prepared using citrate sol-gel method

作者： t.l.·贝内特(t.l. Bennett)

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Journal of Rare Earths 2023年第3期41卷 358-364,I0002页

作者： V.M.Maphiri l.t.Melato M.R.Mhlongo t.t.Hlatshwayo t.E.Motaung l.F.Koao S.V.Motloung Department of Physics Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Mathematics Non Destructive Testing and PhysicsVaal University of TechnologyAndries Potgieter BlvdVanderbijlpark1900South Africa Department of Physics University of PretoriaPretoria0002South Africa Department of Chemistry School of Science in the College of Science Engineering and TechnologyUniversity of South AfricaPreller StreetMuckleneuk RidgeCity of TshwaneP.O Box 392UNISA 0003South Africa Department of Chemistry Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba 9866South Africa Department of Chemical and Physical Sciences Walter Sisulu UniversityMthathaSouth Africa

Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)(ZAOt)nano-powders were synthesized via citrate sol-gel *** AIx moles were varied in the range of 0.25≤x≤*** X-ray powder diffraction(XRD)data reveal that for xthe prepared samples cryst.l.structure consists of mixed phases of the cubic ZnAl_(2)O_(4) and hexagonal ZnO phases,while for x>1.5 the structure consists of single phase of cubic ZnAl_(2)O_(4).the Raman and Fourier-trans form infrared(FtIR)vibrational spectroscopy show the presence of vibrations emanating ZnAl_(2)O_(4) *** electron microscopy(SEM)and transmission electron microscopy(tEM)show the presence of irregular sphere at x>2.0 attributed to ZnAl_(2)O_(4).the phot.l.minescence(Pl)spectroscopy reveals emissions from both the host and tb^(3+)*** from tb^(3+)are observed at 382,414,439,458 nm and 489,545,585,621 nm,which were attributed to the^(5)D_(3)→^(7)F_(6,5,4,2) and ^(5^)D_(4)→^(7)F_(6,5,4,3),*** results confirm that the tb^(3+)occupation site depends on the Alx *** International Commission on Illumination(CIE)colour chromaticity shows that the emission colour can be tuned from blue to green by varying the AIx moles.

关键词： Citrate sol-gel ZnAl_(2)O_(4)/ZnO tb^(3+)-doped Al_(x)moles Phot.l.minescence Rare earths

Nonplanar flow-induced vibrations of a cant.l.vered PIP structure system concurrently subjected to internal and cross flows

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Acta Mechanica Sinica 2019年第6期35卷 1241-1256页

作者： Z.Y.liu t.l.Jiang l.Wang H.l.Dai Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

Pipe-in-pipe(PIP)structures are widely used in offshore oil and gas pipelines to set.l. thermal insulation issues.A PIP structure system usually consists of two concentric pipes and one softer layer for thermal insulation *** tot.l.response of the system is related to the dynamics of both pipes and the interactions between these two concentric *** the current work,a theoretical model for flow-induced vibrations of a PIP structure system is proposed and analyzed in the presence of an internal axial flow and an external cross *** interactions between the two pipes are modeled by a linear distributed damper,a linear distributed spring and a nonlinear distributed spring along the pipe *** unsteady hydrodynamic forces due to cross flow are modeled by two distributed van der Pol wake *** nonlinear partial differential equations for the two pipes and the wake are further discretized by the aid of Galerkin’s technique,resulting in a set of ordinary differential *** ordinary differential equations are further numeri cally solved by using a fourth-order Runge-Kutta integration *** portraits,bifurcation diagrams,an Argand diagram and oscillation shape diagrams are plotted,showing the existence of a lock-in phenomenon and figure-of-eight *** PIP system subjected to cross flow displays some interesting dynamical behaviors different from that of a single-pipe structure.

关键词： Cant.l.vered PIP structure theoretical model Flow-induced vibration Cross flow Internal flow

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撲疟母星预防疟疾之价值

中华医学杂志 1932年第3期 494-495页

作者： t.l.

著者就一己知易发疟疾区,计共居民三百三十,加以实验。每成人一次用扑疟母星为0.04克,每周二次。小儿用量乃按体重计算,即体重千克用0.9克。未实验之前,检查疟疾寄生率,脾涨大率,以及血蛋白之平均价等。以后每隔三月检查一次。同时并检...

著者就一己知易发疟疾区,计共居民三百三十,加以实验。每成人一次用扑疟母星为0.04克,每周二次。小儿用量乃按体重计算,即体重千克用0.9克。未实验之前,检查疟疾寄生率,脾涨大率,以及血蛋白之平均价等。以后每隔三月检查一次。同时并检查按那斐雷坟滋生地。

关键词：

Nonlinear stability of advanced sandwich cylindrical shells comprising porous functionally graded material and carbon nanotube reinforced composite layers under elevated temperature

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1327-1348页

作者： H.V.tUNG l.t.N.tRANG Faculty of Civil Engineering Hanoi Architectural UniversityHa Noi 10000Viet Nam Faculty of Civil Engineering University of Transport TechnologyHa Noi 10000Viet Nam

the nonlinear stability of sandwich cylindrical shells comprising porous functionally graded material(FGM) and carbon nanotube reinforced composite(CNtRC)layers subjected to uniform temperature rise is investigated. two sandwich models corresponding to CNtRC and FGM face sheets are proposed. Carbon nanotubes(CNts) in the CNtRC layer are embedded into a matrix according to functionally graded distributions. the effects of porosity in the FGM and the temperature dependence of properties of all constituent materials are considered. the effective properties of the porous FGM and CNtRC are determined by using the modified and extended versions of a linear mixture rule, respectively. the basic equations governing the stability problem of thin sandwich cylindrical shells are established within the framework of the Donnell shell theory including the von K’arm’an-Donnell nonlinearity. these equations are solved by using the multi-term analytical solutions and the Galerkin method for simply supported *** critical buckling temperatures and postbuckling paths are determined through an iteration procedure. the study reveals that the sandwich shell model with a CNtRC core layer and relatively thin porous FGM face sheets can have the best capacity of thermal load carrying. In addition, unlike the cases of mechanical loads, porosities have beneficial effects on the nonlinear stability of sandwich shells under the thermal load. It is suggested that an appropriate combination of advantages of FGM and CNtRC can result in optimal efficiency for advanced sandwich structures.

关键词： carbon nanotube reinforced composite(CNtRC) porous functionally graded material(FGM) thermal instability cylindrical shell advanced sandwich model

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疟疾用规宁及撲疟母星治疗后之再发率

中华医学杂志 1932年第3期 495-496页

作者： t.l.

关於规定及扑疟母星合剂(Quinine-plasmochine mixtures)治疗疟疾,著者会报告其疗效於前。此次更就治疗後之复发加以研究。更於蚊之蛰伏期试验,以免与重新传染相混。选择四十七个重传染之儿童,一组用规定及扑疟母星合剂治疗,一组仅用规...

关於规定及扑疟母星合剂(Quinine-plasmochine mixtures)治疗疟疾,著者会报告其疗效於前。此次更就治疗後之复发加以研究。更於蚊之蛰伏期试验,以免与重新传染相混。选择四十七个重传染之儿童,一组用规定及扑疟母星合剂治疗,一组仅用规宁治之,一组不加治疗作为比较组。治疗连续五日。治疗前检查一次,其後每隔一周检查一次,共检查四次。结果得知用规定及扑疟母星合剂治疗,其复发率甚低,若只用规定治疗,则复发率较高。

关键词：

Behavioral and olfactory responses of grasshopper hatchlings, Melanoplus sanguinipes, to plant odours and volat.l. compounds

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Chinese Science Bulletin 2004年第2期49卷 136-141页

作者： KANGle t.l.Hopkins StateKeylaboratoryofIntegratedManagementofPestInsects&Rodents.InstituteofZoology ChineseAcademyofSciencesBeijing100080China DepartmentofEntomology KansasStateUniversityManhattanKS66506USA

Behavior and olfactory responses of grasshopper hatchlings, Melanoplus sanguinipes (F.), to odours from plant foliage and volat.l. compounds were tested using a glass Y-tube olfactometer and electroantennogram (EAG)techniques respectively. In single choice trials, newly hatched hoppers were much more sensitive to the odour from intact.l.aves and chopped foliage of ryegrass and wheat than other plants. Chopped sorghum leaves, but not stem-cut sorghum,were also significantly attractive. the orientation responses of grasshopper hatchlings to these plants were highly consistent with those of last instar hoppers and adults. When ryegrass was employed as the control, the odour from stem-cut alfalfa was more attractive. there was no significant difference in hopper orientation responses to the odours from chopped seedlings of sorghum, alfalfa, wheat or ***, significantly more hoppers preferred the chopped ryegrass control to chopped louisanna sage. Measurement of the EAG response of first instar hoppers to these plant odours showed that the odour of louisanna sage elicited the greatest response amplitudes. In olfactory tests using different volat.l. components, Z-3-hexenol, E-3-hexenol,Z-hex-3-enyl acetate, E-2-hexenal and hexenal gave greater EAG responses than geraniol and 1-octen-3-ol. these results are also consistent with comparable data from adults. Newly hatched grasshoppers had similar EAG response profiles to plant materials and chemicals to those of adults, although the absolute EAG values of young hoppers were much lower than those of adults. therefore, newly hatched hoppers were able to distinguish plants from an air control, and even host plants from non-host plants, and the feeding experience of hoppers probably has lit.l. influence on their subsequent ability as adults to identify and locate food plants.

关键词：嗅觉蝗虫挥发性化合物植物保护

BESt APPROXIMAtION FOR WEIERStRASS tRANSFORM CONNECtED WItH SPHERICAl MEAN OPERAtOR

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Acta Mathematica Scientia 2012年第2期32卷 455-470页

作者： l.t.Rachdi N.Msehli Département de Math'ematiques Facult'e des Sciences de Tunis2092 El-ManarTunisia Département de Mathématiques et d'informatique Institut National des Sciences Appliquées et de Technologie de Tunis1080 TunisTunisia

Using reproducing kernels for Hilbert spaces, we give best approximation for Weierstrass transform associated with spherical mean operator. Also, estimates of extremal functions are checked.

关键词： Weierstrass transform spherical mean operator best approximation repro-ducing kernel extremal function

A new green process for biodiesel production from waste oils via cat.l.tic dist.l.ation using a solid acid cat.l.st-Modeling, economic and environment.l.analysis

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Green Energy & Environment 2016年第1期1卷 62-74页

作者： Aashish Gaurav Flora t.t.Ng Garry l.Rempel Department of Chemical Engineering University of Waterloo

the challenges in the chemical processing industry today are environment.l.concerns, energy and capit.l.costs. Cat.l.tic dist.l.ation(CD) is a green reactor technology which combines a cat.l.tic reaction and separation via dist.l.ation in the same dist.l.ation column. Ut.l.zation of CD in chemical process development could result in capit.l.and energy savings, and the reduction of greenhouse gases. the efficacy of CD and the economic merits, in terms of energy and equipment savings, brought by CD for the production of biodiesel from waste oil such as yellow grease is quantified. Process flow sheets for industrial routes for an annual production of 10 million gallon AStM purity biodiesel in a conventional process(reactor followed by dist.l.ation) and CD configurations are modeled in Aspen Plus. Material and energy flows, as well as sized unit operation blocks, are used to conduct an economic assessment of each process. tot.l.capit.l.investment, tot.l.operating and ut.l.ty costs are calculated for each process. the waste oil feedstock is yellow grease containing both triglyceride and free fatty acid. Both transesterification and esterification reactions are considered in the process simulations. Results show a significant advantage of CD compared to a conventional biodiesel processes due to the reduction of dist.l.ation columns, waste streams and greenhouse gas emissions. the significant savings in capit.l.and energy costs together with the reduction of greenhouse gases demonstrate that process intensification via CD is a feasible and new green process for the biodiesel production from waste oils.

关键词： Yellow grease Cat.l.tic dist.l.ation Aspen plus economic analyzer Process intensification