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An earlier explosion date for the Crab Nebula supernova

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Research in Astronomy and Astrophysics 2018年第4期18卷 1-6页

作者： helmut a.abt John W.Fountain Kitt Peak National Observatory Box 26732 Tucson AZ 85726-6732 USA

The Chinese first reported the Crab Nebula supernova on 1054 July 5. Ecclesiastical documents from the near east reported it in April and May of 1054. More than 33 petroglyphs made by Native Americans in the US and Mexico are consistent with sightings both before and after conjunction with the Sun on 1054 May 27. We found a petroglyph showing the new star close to Venus and the Moon, which occurred on 1054 April 12 and April 13, respectively. Collins et al., using the four historical dates, derived a light curve that is like that of a Type Ia supernova. The only remaining problem with this identification is that this supernova was near maximum light for 85 d, which is unlike the behavior of any known supernova.

关键词： celestial mechanics — history and philosophy of astronomy — stars supernovae individual(Crab Nebula)

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如何写好天文学论文(英文)

天文学进展 2002年第4期20卷 299-301页

作者： helmut a.abt 美国基特峰国家天文台

对如何撰写将要在国际上发表的天文学论文给出一些建议。讲述了论文的每一部分(题目、摘要、引言、主要内容、图表及参考文献等)如何可以写得简洁而又能清晰地表达出观点。这是作者根据在多年的编辑生涯中审阅了许多效果迥异的论文后的... 详细信息

对如何撰写将要在国际上发表的天文学论文给出一些建议。讲述了论文的每一部分(题目、摘要、引言、主要内容、图表及参考文献等)如何可以写得简洁而又能清晰地表达出观点。这是作者根据在多年的编辑生涯中审阅了许多效果迥异的论文后的经验之谈。

关键词：天文学论文简洁清晰

Bivalve hinge reveals the structural design of fatigue-resistant deformable ceramic materials

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Science China Materials 2023年第10期66卷 4141-4142页

作者： helmut Colfen Physical Chemistry University of KonstanzUniversitätsstraße 10Box 714 D-78457 KonstanzGermany

Sophisticated principles of design and material integration of biomaterials have long been a major source of inspiration for the development of artificial materials[1,2].In recent years,inspired by the multi-level architecture of biomineral materials such as shell nacre[3,4],tooth enamel[5],and bone[6],several strong and tough bioinspired structural materials like advanced ceramic composites and metallic alloys have been reported.

关键词： composites ceramic structural

Charmonium spectroscopy and decay at CLEO-c

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Chinese Physics C 2010年第6期34卷 621-625页

作者： helmut Vogel Department of Physics Carnegie Mellon University

We report recent results on charmonium spectroscopy and decay from the CLEO-c experiment at the Cornell electrompositron storage ring accelerator, CESR. Most of the results are based on the analysis of 54 pb-1 of luminosity collected at the ψ（2S） resonance, corresponding to 27 M ψ（2S） decays. We concentrate on radiative decays of ψ（2S） and J/ψ, on two-body mesonic decay of XcJ, on hadronic decay of the he, and on higher multipoles in the two-photon cascade ψ（2S）→γχcJ, XcJ→γJ/ψ.

关键词： charmonium radiative decay two-body decay photon transitions higher multipoles

SOLUBILITIES OF CARBON DIOXIDE IN MIXTURES OF n-DECANE-n-HEXADECANE AND n-HEPTANE-TOLUENE

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Chinese Journal of Chemical Engineering 1996年第2期4卷 77-82页

作者：章连众韩世钧 helmut Knapp Institut for Thermodynamik und Reaklionstechnik Technische Universitat Berlin Straβe des 17. Juni 135 D-10623 Berlin Germany

Solubilities of CO2 in binary mixtures of n-decane-n-hexadecane and n-heptane-toluenewere measured in a glass apparatus by a synthetic ***’s constants at several temperaturesand solvent compositions were *** the Henry’s constants of CO2 in mixtures of decaneand hexadecane can be satisfactorily predicted by a simple linear interpolation,prediction of Henry’sconstants for CO2 in mixtures of heptane and toluene requires excess Gibbs energy of the solvent *** standard thermodynamic functions of solution（ΔH0,ΔG0,and ΔS0）were reported.

关键词： carbondioxide n-decane n-hexadecane n-heptane toluene gas solubility thermodynamic properties

Mimicking nature at multiple scales

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Nano Research 2022年第7期15卷 6447-6448页

作者： helmut Cölfen Physical Chemistry Department of ChemistryUniversity of KonstanzUniversitätsstraße 10Box 714D-78457 KonstanzGermany

Nacre-like ceramics have received an intense focus from the structural material community because the inherently low damage resistance of ceramics,which is a fatal deficiency of ceramics as reliable load-bearing *** can be improved through nacreinspired structural designs,i.e.,the“brick-and-mortar”structure with alternating soft and hard layers on the *** technologies have been developed to produce nacre-like ceramics,including freeze casting[1],magnetically assisted slip casting[2],laminating[3]and biomimetic mineralization[4].The obtained artificial ceramics can exhibit extraordinary anti-fracture behavior without introducing a high volume fraction of ductile nonceramic components causing a drastic strength decrease of the ***.

关键词： ceramics material. ceramic

Emerging artificial Bouligand-type structural materials

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National Science Review 2018年第6期5卷 786-787页

作者： helmut Clfen Department of Chemistry University of Konstanz

Until now, the demand for lighter,stronger, tougher and more wearresistant materials has remained unmet for diverse applications, as many structural materials prepared by traditional engineering manufacturing techniqu... 详细信息

关键词： Emerging artificial Bouligand-type structural materials

The quest for conditional independence in prospectivity modeling： weights-of-evidence, boost weights-of-evidence, and logistic regression

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Frontiers of Earth Science 2016年第3期10卷 389-408页

作者： helmut SCHAEBEN Georg SEMMLER Department of Geophysics and Geoinformatics TU Bergakademie Freiberg Freiberg 09596 Germany

The objective of prospectivity modeling is prediction of the conditional probability of the presence T = 1 or absence T = 0 of a target T given favorable or prohibitive predictors B, or construction of a two classes {0,1} classification of T. A special case of logistic regression called weights-of-evidence （WofE） is geolo- gists＇ favorite method of prospectivity modeling due to its apparent simplicity. However, the numerical simplicity is deceiving as it is implied by the severe mathematical modeling assumption of joint conditional independence of all predictors given the target. General weights of evidence are explicitly introduced which are as simple to estimate as conventional weights, i.e., by counting, but do not require conditional independence. Complementary to the regres- sion view is the classification view on prospectivity modeling. Boosting is the construction of a strong classifier from a set of weak classifiers. From the regression point of view it is closely related to logistic regression. Boost weights-of-evidence （BoostWofE） was introduced into prospectivity modeling to counterbalance violations of the assumption of conditional independence even though relaxation of modeling assumptions with respect to weak classifiers was not the （initial） purpose of boosting. In the original publication of BoostWofE a fabricated dataset was used to ＂validate＂ this approach. Using the same fabricated dataset it is shown that BoostWofE cannot generally compensate lacking condi- tional independence whatever the consecutively proces- sing order of predictors. Thus the alleged features of BoostWofE are disproved by way of counterexamples, while theoretical findings are confirmed that logistic regression including interaction terms can exactly com- pensate violations of joint conditional independence if the predictors are indicators.

关键词： general weights of evidence joint conditionalindependence naive Bayes model Hammersley-Cliffordtheorem interaction terms statistical significance

Oxidative eustress:the physiological role of oxidants

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Science China(Life Sciences) 2023年第8期66卷 1947-1948页

作者： helmut Sies Institute of Biochemistry and Molecular Biology I Heinrich-Heine-University DüsseldorfDüsseldorf 40225Germany Leibniz Research Institute for Environmental Medicine Düsseldorf 40021Germany

The perception of a pivotal role of reactive oxygen species(ROS)(Sies et al.,2022),reactive nitrogen species(RNS)and electrophiles(Parvez et al.,2018)in cell biology and physiology has gained widespread *** recent yea... 详细信息

关键词： gained acceptance accumulated