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101.
J.J. BorgerS.R. Hashemi-Nezhad D. AlexievR. Brandt W. WestmeierB. Thomauske J. AdamM. Kadykov S. Tiutiunnikov 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2012,664(1):103-110
The Energy plus Transmutation (EpT) set-up of the Joint Institute for Nuclear Research (JINR), Dubna, Russia is composed of a lead spallation target surrounded by a blanket of natural uranium. The resultant neutron spectrum is a combination of spallation and fission spectra, modified by a reflective external layer of polyethylene and an internal absorbing layer of cadmium. The EpT set-up was irradiated with a beam of 4 GeV deuterons from the Nuclotron Accelerator at JINR. The spatial distribution of thorium fission rate within the assembly was determined experimentally, using a fission track detector technique, and compared with Monte Carlo predictions of the MCNPX code. Contributions of neutrons, protons, deuterons, photons and pions to total fission were taken into account. Close agreement between the experimental and calculated results was found. 相似文献
102.
Pleurotus ostreatus laccase recovery from residual compost using aqueous two‐phase systems 下载免费PDF全文
103.
Dr. Yuriy V. Sheludko Dr. Jascha Volk Dr. Wolfgang Brandt Prof. Heribert Warzecha 《Chembiochem : a European journal of chemical biology》2020,21(14):1976-1980
Human drug-metabolizing cytochrome P450 monooxygenases (CYPs) have enormous substrate promiscuity; this makes them promising tools for the expansion of natural product diversity. Here, we used CYP3A4 for the targeted diversification of a plant biosynthetic route leading to monoterpenoid indole alkaloids. In silico, in vitro and in planta studies proved that CYP3A4 was able to convert the indole alkaloid vinorine into vomilenine, the former being one of the central intermediates in the ajmaline pathway in the medicinal plant Rauvolfia serpentina (L.) Benth. ex Kurz. However, to a much larger extent, the investigated conversion yielded vinorine (19R,20R)-epoxide, a new metabolite with an epoxide functional group that is rare for indole alkaloids. The described work represents a successful example of combinatorial biosynthesis towards an increase in biodiversity of natural metabolites. Moreover, characterisation of the products of the in vitro and in planta transformation of potential pharmaceuticals with human CYPs might be indicative of the route of their conversion in the human organism. 相似文献
104.
Howard E. Brandt 《Quantum Information Processing》2012,11(3):787-839
An introduction is first given of recent developments in the Riemannian geometry of quantum computation in which the quantum
evolution is represented in the tangent space manifold of the special unitary unimodular group for n qubits. The Riemannian
right-invariant metric, connection, curvature, geodesic equation for minimal complexity quantum circuits, Jacobi equation,
and the lifted Jacobi equation for varying penalty parameter are reviewed. Sharpened tools for calculating the geodesic derivative
are presented. The geodesic derivative may facilitate the numerical investigation of conjugate points and the global characteristics
of geodesic paths in the group manifold, the determination of optimal quantum circuits for carrying out a quantum computation,
and the determination of the complexity of particular quantum algorithms. 相似文献
105.
承包商对工程的具体掌控力要远高于业主方,业主方面对工程实施中的各种问题往往鞭长莫及。为了帮助业主方从源头上实现项目的成功管理,就要发挥工程咨询机构的作用。本文论述了工程咨询机构在招标阶段项目管理的核心内容,指明了其在招标阶段的关键工作,在一定程度上实现了项目资源的优化配置,为业主节约了成本和效益最大化。同时,也分析了我国目前项目管理发展中存在的问题,并参照国内外先进管理思想和管理模式提出了我国工程咨询机构的发展方向及相应对策,对我国工程咨询业的发展有一定的参考价值。 相似文献
106.
Analyses of structurally modified quasi‐solid‐state electrolytes using electrochemical impedance spectroscopy for dye‐sensitized solar cells 下载免费PDF全文
Seok‐Jun Seo Andreas Hinsch Welmoed Veurman Henning Brandt Moon‐Sung Kang Sung‐Hee Shin Seung‐Hyeon Moon 《应用聚合物科学杂志》2014,131(1)
Electrochemical properties of structurally modified quasi‐solid‐state electrolytes were examined using porous substrates (PSs). The PS was prepared into two categories by a phase inversion method with a brominated poly(phenylene oxide) (BPPO): the sponge and finger types. Effects of the humidification and cosolvent compositions on the morphology of the PS were analyzed by scanning electron microscopy. In all cases of the PSs, a higher VOC was observed of about 0.1 V than that of a liquid electrolyte owing to a suppressed back electron charge transfer. In addition, the PS prepared by the polymer solution of 1 : 4 : 1 (BPPO : N‐methyl‐2‐pyrrolidone : butyl alcohol) with the humidification process showed better photovoltaic properties in terms of the current density and conversion efficiency owing to the appropriate combinations of pore size, tortuosity, and interconnectivity. Effects of the pore structures were intensively examined using electrochemical impedance spectroscopy. The impedance results revealed that large pores at the surface layers are advantageous for a lower RS and RTiO2. Meanwhile, the straight inner structure is beneficial for the facile I?/I3? diffusion, thus lowering RPt. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39739. 相似文献
107.
Schwaibold Schormüller Beckel W. Sutthoff Lars Erlandsen v. Skramlik W. Schreiber Kanitz Bierotte M. Steiner W. Wodsak G. Steinhoff H. J. Steinbeck Frey-Wyssling M. Gordienko K. Dirr Pawletta Stelzer W. Wodsak W. Bartels Hoepke G. Stamm Brüning W. Hämmerle Schnetka K. Felix H. Schülke Kluge Krzywanek W. Brandt Gertraude Körner-Hennig K. J. Demeter Damm J. Ph. Bruno Roßmann W. Karlowa H. Ketterl L. W. Jirak W. Preiß Diemair W. Ludorff Jahr Griebel J. J. van Eck W. Preiß C. Pyriki K. Müller Jesser K. Boresch Fr. Bartschat 《European Food Research and Technology》1939,77(3):290-336
108.
109.
W. Limmer M. Glunk J. Daeubler T. Hummel W. Schoch C. Bihler H. Huebl M.S. Brandt S.T.B. Goennenwein R. Sauer 《Microelectronics Journal》2006,37(12):1490-1492
The magnetic anisotropy of a 40-nm-thick (Ga,Mn)As film with 5% Mn grown on GaAs(1 1 3)A is studied by means of magnetotransport and ferromagnetic resonance (FMR) spectroscopy. In addition to the cubic and a weak uniaxial in-plane anisotropy, two uniaxial out-of-plane contributions along [1 1 3] and [0 0 1] are found. Using the anisotropy parameters determined from FMR, the longitudinal and transverse resistivities measured as a function of magnetic field orientation and strength are well modelled within the framework of a single ferromagnetic domain. In particular, the low-field data which are strongly affected by sudden jumps of the magnetization are well reproduced. 相似文献
110.
CRIGOS: a compact robot for image-guided orthopedic surgery 总被引:5,自引:0,他引:5
Brandt G. Zimolong A. Carrat L. Merloz P. Staudte H.-W. Lavallee S. Radermacher K. Rau G. 《IEEE transactions on information technology in biomedicine》1999,3(4):252-260
The CRIGOS (compact robot for image-guided orthopedic surgery) project was set up for the development of a compact surgical robot system for image-guided orthopedic surgery based on user requirements. The modular system comprises a compact parallel robot and a software system for planning of surgical interventions and for supervision of the robotic device. Because it is not sufficient to consider only technical aspects in order to improve clinical routines the therapeutic outcome of conventional interventions, a user-centered and task-oriented design process has been developed which also takes human factors into account. The design process for the CRIGOS system was started from requirement analysis of various orthopedic interventions using information gathered from literature, questionnaires, and workshops with domain experts. This resulted in identification of conventional interventions for which the robotic system would improve the medical and procedural quality. A system design concept has been elaborated which includes definitions of components, functionalities, and interfaces, Approaches to the acquisition of calibrated X-rays will be presented in the paper together with design and evaluation of a first human-computer interface. Finally, the first lab-type parallel robot based on low-cost standard components is presented together with the first evaluation results concerning positioning accuracy 相似文献