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Journal of Energy Chemistry 2021年第6期30卷 386-391,I0010页

作者： Manuel vásquez-Montoya Juan f.Montoya Daniel Ramirez franklin Jaramillo Centro de Investigación Innovación y Desarrollo de Materiales CIDEMATUniversidad de Antioquia UdeACalle 70 No.52-21MedellínColombia

Upscaling perovskite solar cell fabrication is one of the key challenges in the pathway for *** slow evaporation of frequently used solvents(DMf or DMSO) limits the fast perovskite layer crystallization,hindering their implementation in large scale deposition ***,methylamine-based precursors have demonstrated rapid crystallization,leading to uniform and specular ***,their application has been limited to MAPbI3 perovskites with limited efficiency and *** this work,we report the requirements for stabilizing α-phase of mixed cation perovskites with high amount of formamidinium by using a methylamine-based *** found that even though,there are many methods for incorporating the methylamine(MA) in precursors or films;the MA content determines stabilization of the α-phase and therefore the viscous-solution route is the only method to incorporate high amounts of *** low amounts of MA,perovskite tend to crystallize in 1D dimensional fA_(3)(MA)PbI5 phases due to the incomplete solvation of the *** contrast,high MA ratio induces a full solvation of the clusters,leading to a rapid crystallization and a full stabilization of the active 3D α-*** results open a window in the development and understanding of new precursors for the fabrication of high efficient,stable and scalable perovskite devices.

关键词： Methylamine Stabilizingα-phase Mixed cation perovskite precursor formamidinium Upscaling Perovskite Solar cells

New filler metal systems for the brazing of titanium alloys

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China Welding 2015年第3期24卷 1-5页

作者： v. f. Khorunov S. v. Maksymova v. v. voronov E.O. Paton Electric Welding Institute NASU 11 Bozhenko Str. Kiev 03680 Ukraine

It＇ s well known welding takes the leading role in development of titanium structures. However, in number of cases technological processes of brazing are more appropriate and, sometimes, being the single possible, in particular, during production of multilayer thin-wall structures. It should be noted that brazing filler metals of Ti-Cu-Ni, Ti-Zr-Cu-Ni, Zr-Ti-Ni and Cu-Zr-Ti systems in a form of plastic foils, as well as in powder form are mainly used in world practice for brazing of titanium alloys. Present work provides the results of complex investigations of brazing filler metals of Ti-Zr-fe, Ti-Zr-Mn and Ti-Zr-Co systems using differential thermal analysis, light and scanning microscopy, X-ray microspectrum analysis. Data on melting ranges of pilot alloys were obtained, and liquidas su^Caces of given systems using simplex-lattice method were build. Brazing filler metals covering brazing temperature range of current structural titanium materials based on solid solutions as well as intermetallics were proposed. Structure, chemical inhomogeniety and strength characteristics of brazed joints were studied. It is determined that brazing of solid solution based alloys （OT4, vT6 ） using indicated brazing fiUer metals ensures strength characteristics of joints, which are not inferior to that obtained with application of known brazing filler metals even if they are received at lower brazing temperature.

关键词： vacuum brazing titanium alloys inter-metallic alloys brazing filler metals brazed joints structure,strength of brazed joints

Command functions of open loop galvanometer scanners with optimized duty cycles

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Theoretical & Applied Mechanics Letters 2012年第4期2卷 34-39页

作者： v.f.Duma 3OM Optomechatronics Group Faculty of EngineeringAurel Vlaicu University of AradArad 310130Romania

The paper approaches the problem of the command functions of galvanometer-based scanners （GS） that are necessary to produce the linear plus parabolic scanning function of the GS, which we have proved previously to produce the highest possible duty cycle （i.e., time efficiency） of the device. We have completed this theoretical aspect （which contradicted what has been stated previously in the literature, where it has been considered that the linear plus sinusoidal scanning function was the best） with the experimental study of the most used scanning functions of the GSs （sawtooth, sinusoidal and triangular）, with applications in biomedical imaging, in particular in optical coherence tomography, demonstrating that the triangular function is always the best one to be applied, from both an optical and a mechanical point of view. In the present study the input voltage/command function which should be applied to the GS to produce the desired triangular scanning function （with controlled non-linearity for the fastest possible stop-and-turn portions） was determined analytically, in relationship with the active torque that drives the device. This command function is analyzed with regard to the specific, respectively required parameters of the GS： natural frequency and damping factor, respectively scan speed and amplitude. The modeling in an open loop control structure of the GS is finally discussed as a trade-off between using the highest possible duty cycle and minimizing the maximum peaks of the input voltage.

关键词： scanners galvanometer scanner optomechatronics scanning functions command func-tions duty cycle driving torque

Technosols Made of Wastes to Improve Physico-Chemical Characteristics of a Copper Mine Soil

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Pedosphere 2013年第1期23卷 1-9页

作者： v.ASENSIO f.A.vEGA M.L.ANDRADE E.f.COvELO Department de Bioloxía vexetal e Ciencia do Solo Facultade de Bioloxia Universidade de VigoLagoas Marcosende 36310 Vigo Pontevedra (Spain)

Mine tailing soils created from the copper extraction in Touro Mine （Northwest Spain） are very degraded both physically and chemically. Three plots in this mine tailing were amended with Technosols in different proportions in each one to know if this mixture improved the physico-chemical characteristics of the mine soil and contaminated it with heavy metals. The Technosols were made of organic wastes, including mussel residues, wood fragments, sewage sludges and paper mill ashes. An unamended area was used as a control soil. Pseudototal and diethylenetriaminepentaacetic acid （DTPA）-extractable contents of A1, Cr, Cu, fe, Mn, Ni, Pb and Zn were determined in soil samples. The untreated soil had significant limitations for vegetation growth. All the Technosols improved the properties of the mine soil by increasing organic carbon and pH value, but they added Ni, Pb or Zn to the soil. It is advisable to check whether the heavy metal concentrations of the wastes are hazardous or not before adding to soils. It is also necessary to study the effect of these wastes over time and in more areas to conclude if they are actually favourable to restore degraded mine soils.

关键词： heavy metals mine tailing vegetation growth waste amendment

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二十世纪物理学

二十世纪物理学

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

作者： v.f.·韦斯科夫(v.f. Weisskopf)

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther f.-E.Brack f.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Applications—Influence of Biology on Engineering

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Journal of Bionic Engineering 2006年第3期3卷 161-177页

作者： Julian f. v. vincent Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

Examples are presented showing the way in which biological systems produce a range of functions which can be implemented in engineering, such as feedback-control of stiffness （muscles and nervous system）, the design of fault-free structures （trees） and damage-tolerant materials （wood） and high performance insulation （penguin feathers） and shock absorbers （hedgehog spines）.

关键词： Applications Influence of Biology on Engineering

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早期电影理论批判史

世界电影 1983年第5期 6-37页

作者： v.f.帕金斯 ,闻谷

这篇文章原为英国电影研究家帕金斯的著作《电影作为电影》(1972)的第一、二章,后又被收进《电影与方法》(比尔·尼古尔斯编,1976)一书,现在的译文即根据选编本翻译的。帕金斯的这篇文章对截止六十年代的各家电影理论作了比较简括的介... 详细信息

这篇文章原为英国电影研究家帕金斯的著作《电影作为电影》(1972)的第一、二章,后又被收进《电影与方法》(比尔·尼古尔斯编,1976)一书,现在的译文即根据选编本翻译的。帕金斯的这篇文章对截止六十年代的各家电影理论作了比较简括的介绍,并从他的科学美学的立场出发,批评了“传统的”“画面一蒙太奇至上”论和与之相对立的“物象至上”论。他要求电影理论家把研究重点从表现方法转移到影片内容上来,转移到观众的感觉能力上来。“一种有用的理论应当把重点从创造转移到感受上来,使人们的注意力回复到眼前所见的影片上来。”帕金斯对于清规戒律式的电影理论,即他所说的“出于对电影技巧的某个特殊方面的偏爱来制定的批评标准”,十分反感。在他看来,最理想的电影理论则是注重影象和观众的相互影响的“作者论”。本刊1982年第4期曾在“关于电影理论问题”栏目下,发表了卡斯比埃及汉德逊评论各家电影理论的文章,帕金斯此文也属同一性质。这些文章观点不尽相同,追求的目标互异,正确与谬误并见,对理论问题感兴趣的读者不妨对照比较一下,必有所得。

关键词：电影导演蒙太奇摄影机摄影设备爱因汉姆电影画面影片理论家

A non-relativistic model for the[cc]■ tetraquark

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Chinese Physics C 2019年第1期43卷 36-55页

作者： v.R.Debastiani f.S.Navarra Departamento de física Teórica and IfIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Instituto de física Universidade de Sa?o Paulo Institut de Physique Théorique Université Paris SaclayCEA CNRS

We use a non-relativistic model to study the spectroscopy of a tetraquark composed of [cc]■ in a diquark-antidiquark *** numerically solving the Schr?dinger equation with a Cornell-inspired potential,we separate the four-body problem into three two-body ***-dependent terms(spin-spin,spin-orbit and tensor)are used to describe the splitting structure of the ■ spectrum and are also extended to the interaction between *** experimental data on charmonium states are used to fix the parameters of the model and a satisfactory description of the spectrum is *** find that the spin-dependent interaction is sizable in the diquark-antidiquark system,despite the heavy diquark mass,and also that the diquark has a finite size if treated in the same way as the ■ *** find that the lowest S-wave T 4c tetraquarks might be below their thresholds of spontaneous dissociation into low-lying charmonium pairs,while orbital and radial excitations would be mostly above the corresponding charmonium pair ***,we repeat the calculations without the confining part of the potential and obtain bound diquarks and bound *** might be relevant to the study of exotic charmonium in the quark-gluon *** T 4c states could be investigated in the forthcoming experiments at the LHC and BelleⅡ.

关键词： tetraquark charmonium diquark-antidiquark nonrelativistic spin

Rare-earth and trace element imprints on the origin and tectonic setting of gabbro-diorite complex in the Pan-African belt of Southeast Obudu Plateau,Nigeria

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Chinese Journal Of Geochemistry 2009年第3期28卷 239-247页

作者： Ukaegbu v.U. Beka f.T. Department of Geology University of Port HarcourtPort HarcourtNigeria

A gabbro-diorite plutonic complex from the Southeast Obudu Plateau, representing limited volumes of magma, was studied for its trace and rare-earth element characteristics, in an attempt to document its genetic and geodynamic history. Geochemical studies indicate that the gabbro samples are characterized by variable concentrations and low averages of such index elements as Cr (40×10-6–200×10-6; av. 80×10-6), Ni (40×10-6–170×10-6; 53.33×10-6) and Zr (110×10-6–240×10-6; 116.67×10-6); variable and high averages of Rb (3×10-6–270×10-6; 80.67×10-6), Sr (181×10-6–1610×10-6; 628.17×10-6) and U (0.14×10-6–3.46×10-6; 1.51×10-6), and fairly uniform Co (34×10-6–49×10-6; 36.33×10-6) and Sc (23×10-6–39×10-6; 34.5×10-6), while the diorite samples exhibit higher trace element compositions. The range of REE contents and distinctive chondrite-normalized patterns indicate moderate fractionation with slight positive Eu anomaly in the diorites to very low fractionation with flat patterns and slight positive Eu anomaly in the gabbros. However, the general element systematics of the samples, especially LILE (Ba, Rb, Sr, Cs and Pb), HfSE (Zr, Th, U, Hf, Mo, W, Nb and Sn), relatively immobile elements (Zr, Ni, Cr) and REE, suggests a differentiation model, involving fractional crystallization of olivine and clinopyroxene from a partial melt generated beneath an island arc complex. A possible model for the complex is therefore an island arc setting, the development of which was dominated by calc-alkaline magmatism across the Obudu Plateau.

关键词：构造环境微量元素尼日利亚辉长岩闪长岩起源高原痕迹