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A Method for the squaring of a Circle

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Advances in Pure Mathematics 2022年第9期12卷 535-540页

作者： Lyndon O. barton Delaware state University Dover USA

This paper presents a Method for the squaring of a circle (i.e., constructing a square having an area equal to that of a given circle). The construction, when applied to a given circle having an area of 12.7 cmsup>2sup>, it produced a square having an area of 12.7 cmsup>2sup>, using only an unmarked ruler and a compass. This result was a clear demonstration that not only is the construction valid for the squaring of a circle but also for achieving absolute results (independent of the number pi (π) and in a finite number of steps) when carried out with precision.

关键词： Famous Problems in Mathematics Archimedes College Mathematics Cycloidal Construction Mean Proportional Principle squaring the Circle Quadrature Geometer’s sketch Pad College Geometry

Preparation of some new arylseleno compounds and application in the oxidation of olefins

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Chinese Journal of Chemistry 1990年第3期8卷 274-280页

作者： barton D.H.R MILLIET P. LUsINCHI X. Department of Chemistry Texas A.& M.UniversityCollege StationTexas 77843U.S.A. Institut de Chimie des substances Naturelles C.N.R.S.91190 Gif-sur-YvetteFrance

Fifteen pyridine and substituted benzene diselenides,seleninic acids and seleninic anhydrides have been *** them,4,4'-dipyridinediselenide,bis(2,4-dimethoxyphenyl)diselenide, 2,4-dimethoxyphenyl seleninic acid,2-pyridineseleninic acid,2-pyridineseleninic anhydride,4-pyridine- seleninic anhydride,2-nitrophenyl seleninic anhydride and 4-nitrophenyl seleninic anhydride were new *** regioselective oxidation or dehydrogenation of β-pinene,3β-benzoyloxycholest- 5-ene and androstan-3-one have been studied and compared.2-Pyridineseleninic anhydride is a more efficient oxidant than the others;most of the substituted benzeneseleno derivatives did not give the expected products.

关键词： Preparation of some new arylseleno compounds and application in the oxidation of olefins

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Experimental study on reduction of U (Ⅵ) by an anaerobic bacterium, shewanella putrefaciens: Application to sandstone-hosted interlayer oxidation-zone type uranium deposits, China

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science China Earth sciences 2005年第3期48卷 346-352页

作者： L.L.barton Department of Biology University of New Mexico Albuquerque NM 87131-1116USA

An experimental study on reduction of U (VI) by anaerobic bacteria, shewanella putrefaciens, is first reported here in China. The experimental conditions were: 35℃ and pH = 7.0—7.4, corresponding to a physicochemical environments in which the sandstone-hosted in- terlayer oxidation-zone type uranium deposit formed in Northwest China’s Xinjiang. Bacteria adopted in the present experiment, shewanella putrefaciens, occur extensively in natural envi- ronment. Our study shows that nano-crystal precipitates of uraninite quickly occurred on the surface of the cells within one week. It was found that the pitchblende was characterized by a random arrangement of uraninite nanocrystals (2—4 nm) in it, significantly different from natural pitchblende in which uraninite nanocrystals are arranged in order. Finally, a possible mechanism of uranium biomineralization by microorganisms in the deposits is discussed. Our investigation may supply a technical train of thoughts for bioremediation of nuclear-contaminated water envi- ronments and for underground dissolving extraction of the sandstone-hosted uranium ores.

关键词： anaerobic bacteria, reduction, pitchblende, sandstone-hosted uranium deposit, experimental study.

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Thermoelastic stress analysis of holes in cylindrical shells

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Thermoelastic stress analysis of holes in cylindrical shells

The Extraordinary Circumstance on Board H. M. s. steadfast （Ⅱ）

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作者： s.Quinn J.M.Dulieu-barton NNC Ltd. Booths Hall Chelford Road Knusford Cheshire WA16 8QZ UK University of southampton School of Engineering Sciences Highfield Southampton SO17 1BJ UK

＜正＞ Thermoelastic stress analysis is used to obtain the stress concentration factors （sCFs） from a variety of circular holes in cylinders. The cylinders are loaded in uniaxial tension, uniaxial compression and a combination of bending and compression. Firstly radial holes are investigated and the results from the thermoelastic data obtained by the sPATE equipment are compared to previous experimental and numerical work. sCFs are then obtained from offset, oblique and offset-oblique holes using the Deltatherm system. The effect of hole obliquity and direction of applied load relative to the hole geometry is discussed.

关键词： Thermoelastic stress analysis sPATE deltatherm offset oblique and offset-oblique holes cylinders stress concentration factors (sCFs)

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考试与评价（高中英语教师版） 2009年第3期 44-47页

作者： barton Paul Levenson Kurt Mitchell

se-Bearing Colloidal Particles Produced by sulfate-Reducing Bacteria and sulfide-Oxidizing Bacteria: TEM study

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Advances in Microbiology 2013年第2期3卷 205-211页

作者： Huifang Xu Larry L. barton NAsA Astrobiology Institute Department of Geoscience University of Wisconsin-Madison Madison USA

As determined by transmission electron microscopy (TEM), the reduction of selenate and selenite by Desulfovibrio desulfuricans, a sulfate-reducing bacterium, produces spherical (se, s) sub-micro particles outside the cell. The particles are crystalline or amorphous, depending on medium composition. Amorphous-like se-rich spherical particles may also occur inside the bacterial cells. The bacteria are more active in the reduction of selenite than selenate. The Desulfovibrio desulfuricans bacterium is able to extract s in the (s, se) solid solution particles and transform s-rich particles into se-rich and se crystals. Photoautotrophs, such as Chromatium spp., are able to oxidize sulfide (s2-). When the bacteria grow in sulfide- and selenide-bearing environments, they produce amorphous-like (s, se) globules inside the cells. TEM results show that compositional zonation in the (s, se) globules occur in Chromatium spp. collected from a top sediment layer of a se-contaminated pond. s2-?may be from the products of sulfate-reducing bacteria. Both the sulfate-reducing bacteria and photosynthetic Chromatium metabolize s preferentially over se. It is proposed that the s-rich zones are formed during photosynthesis (day) period, and the se-rich zones are formed during respiration active (night) period. The results indicate that both Desulfovibrio desulfuricans and Chromatium spp. are able to immobilize the oxidized selenium (selenate and/or selenite) in the forms of elemental selenium and (se, s) solid solutions. The bacteria reduce s in the (se, s) particles and further enrich se in the crystalline particles. The reduced s combines with Fe2+ to form amorphous Fes.

关键词： selenium sulfate-Reducing Bacteria sulfide-Oxidizing Bacteria Transmission Electron Microscopy

THE CHANNEL TUNNEL:A NEW UNDERWATER CONNECTION BETWEEN BRITAIN AND EUROPE

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英语学习 1999年第1期 25-26页

作者： Bob barton 陈海君

Napoleon approved plans for a tunnelbeneath the English Channel *** British began digging onein *** tunnel was ***-rope has had to wait until the end of the 20thcenrury for the Channel *** nearlytwo centuries of dreaming,the island ofGreat Britain is connected to ContinentalEurope for the first time since the Ice Age,when the two joined land masses drifted *** May 6,1994,Britain’s Queen Eliza-beth Ⅱ and France’s President Mitterrand

关键词： THE CHANNEL TUNNEL:A NEW UNDERWATER CONNECTION BETWEEN BRITAIN AND EUROPE

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局部自反原理的推广

科学通报 1993年第10期38卷 876-877页

作者： T.barton 俞鑫泰 Memphis state Univ.UsA 华东师范大学数学系上海200062

大家知道,局部自反原理是Banach空间理论中最基本的定理之一。本文得到了局部自反原理的“最完备”的形式。我们证明定理1 设E是X^(**)的一个有限维子空间,F是X~*的一个自反子空间,对于任给ε>0,则存在一个线性算子s:E→X使得‖s‖‖s^(... 详细信息

大家知道,局部自反原理是Banach空间理论中最基本的定理之一。本文得到了局部自反原理的“最完备”的形式。我们证明定理1 设E是X^(**)的一个有限维子空间,F是X~*的一个自反子空间,对于任给ε>0,则存在一个线性算子s:E→X使得‖s‖‖s^(-1)‖sx=x,其中x∈E∩X,且f(sx^(**)=x^(**)(f),对一切x^(**)∈X,f∈F.

关键词：局部自反原理巴拿赫空间

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Monitoring adenoviral based gene delivery in rat glioma by molecular imaging

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World Journal of Clinical Oncology 2013年第4期4卷 91-101页

作者： Nadimpalli Ravi s Varma Kenneth N barton Branislava Janic Adarsh shankar AsM Iskander Meser M Ali Ali s Arbab Cellular and Molecular Imaging Laboratory Department of RadiologyHenry Ford HospitalDetroitMI 48202United States Department of Radiation Oncology Henry Ford HospitalDetroitMI 48202United States

AIM:To determine whether endothelial progenitor cells(EPCs)can be used as delivery vehicle for adenoviral vectors and imaging probes for gene therapy in ***:To use cord blood derived EPCs as delivery vehicle for adenoviral vectors and imaging probes for glioma gene therapy,a rat model of human glioma was made by implanting U251 cells *** were transfected with an adenovirus(AD5/carrying hNIs gene)and labeled with iron oxide and inoculated them directly into the tumor 14 d following implantation of U251 *** resonance imaging(MRI)was used to in vivo track the migration of EPCs in the *** expression of gene products was determined by in vivo Tc-99m single photon emission computed tomography(sPECT).The findings were validated with immunohistochemistry(IHC).REsULTs:EPCs were successfully transfected with the adenoviral vectors carrying hNIs which was proved by significantly(Psfected *** of EPCs following transfection and iron labeling was not *** vivo imaging showed the presence of iron positive cells and the expression of transgene(hNIs)product on MRI and sPECT,respectively,all over the tumors following administration of transfected and iron labeled EPCs in the *** confirmed the distribution of EPC around the tumor away from the injection site and also showed transgene expression in the *** results indicated the EPCs’ability to deliver adenoviral vectors into the glioma upon intratumor ***:EPCs can be used as vehicle to deliver adenoviral vector to glioma and also act as imaging probe at the same time.

关键词： Cord blood endothelial progenitor cells Adenovirus Human sodium iodide symporter single photon emission computed tomography Magnetic resonance imaging