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1.
Vibronic interactions have received increasing attention in modern structural chemistry. Edward Teller played a pioneering
role in understanding and describing them during the “molecular physics” period of his scientific career. Very little is known
about the two scientists who contributed significantly to our knowledge about these effects and whose names have become associated
with Teller’s. This Editorial is devoted to Hermann Jahn and Rudolf Renner and attempts to lift them out of oblivion by paying
them tribute for their contributions.
相似文献
István Hargittai (Corresponding author)Email: |
2.
Philip J. Stewart 《Foundations of Chemistry》2007,9(3):235-245
Mendeleev’s failure to represent the periodic system as a continuum may have hidden from him the space for the noble gases.
A spiral format might have revealed the significance of the wide gaps in atomic mass between his rows. Tables overemphasize
the division of the sequence into ‘periods’ and blocks. Not only do spirals express the continuity; in addition they are more
attractive visually. They also facilitate a new placing for hydrogen and the introduction of an ‘element of atomic number
zero’.
相似文献
Philip J. StewartEmail: |
3.
Robert J. Deltete 《Foundations of Chemistry》2008,10(3):187-221
This is the third of a series of essays on the development and reception of Wilhelm Ostwald’s energetics. The first essay
described the chemical origins of Ostwald’s interest in the energy concept and his motivations for seeking a comprehensive
science of energy. The second essay and the present one discuss his various attempts, beginning in 1891 and extending over
almost 3 years, to develop a consistent and coherent energetic theory. A final essay will consider reactions to this work
and Ostwald’s replies, and will also seek to evaluate his program of research. Ostwald’s project—to reconstruct physics and
chemistry “as a pure energetics”—is worth attending to for several reasons: first, because Ostwald did ground-breaking work
in chemistry (he was awarded a Nobel Prize in 1909 for his studies in catalysis and rates of reaction); second, because an
important school of physical chemistry formed around him at Leipzig, a school that promoted his ideas; and, finally, because
he was a prominent and vigorous participant in debates at the end of the nineteenth century concerning the proper course of
physical theory.
相似文献
Robert J. DelteteEmail: |
4.
Hinne Hettema 《Foundations of Chemistry》2008,10(2):135-142
Michael Weisberg’s recent 2007 paper on the chemical bond makes the claim that the chemical notion of the covalent bond is
in trouble. This note casts doubts on that claim.
相似文献
Hinne HettemaEmail: |
5.
6.
This paper describes the COMAR database for certified reference materials (CRMs). The Web-based version of COMAR is freely
accessible via the Internet. COMAR was established to assist laboratories in finding the CRMs needed. The database is maintained
in a collaboration of the world’s major CRM producers. The planned changes in the database as agreed at the last COMAR council
meeting in Prague in May 2006 are indicated.
相似文献
Thomas SteigerEmail: |
7.
Structural formulas and explanation in organic chemistry 总被引:1,自引:1,他引:0
W. M. Goodwin 《Foundations of Chemistry》2008,10(2):117-127
Organic chemists have been able to develop a robust, theoretical understanding of the phenomena they study; however, the primary
theoretical devices employed in this field are not mathematical equations or laws, as is the case in most other physical sciences.
Instead it is diagrams, and in particular structural formulas and potential energy diagrams, that carry the explanatory weight
in the discipline. To understand how this is so, it is necessary to investigate both the nature of the diagrams employed in
organic chemistry and how these diagrams are used in the explanations of the discipline. I will begin this paper by characterizing
some of the major ways that structural formulas used in organic chemistry. Next I will present a model of the explanations
in organic chemistry and describe how both structural formulas and potential energy diagrams contribute to these explanations.
This will be followed by several examples that support my abstract account of the role of diagrams in the explanations of
organic chemistry. In particular, I will consider both the appeal to ‘hyperconjugation’ in the explanation of alkene stability
and how the idea of ‘ring strain’ was developed to explain the relative stability of cyclic compounds.
相似文献
W. M. GoodwinEmail: |
8.
Meredith Tromble 《Foundations of Chemistry》2009,11(1):51-60
This paper explores the use of chemical symbolism in works by the new media artist Sonya Rapoport, with a focus on the pivotal
Cobalt series from the late 1970s. These works, drawings on computer printouts generated by research at the Lawrence Berkeley Laboratory,
respond to experiments in nuclear chemistry. They mark the beginning of three productive decades in which Rapoport produced
a variety of images related to chemistry in her work. She states, “I looked for authentic research projects that were interesting
to me, preferably with captivating pictorial subject matter. Then came the creative chaotic process of resolving a cohesive
product that combined scientific research with art concept.” Rapoport had an unusual degree of access to scientific materials
through her husband, organic chemist Henry Rapoport, a faculty member at the University of California, Berkeley. At the time
of production, these works were outside mainstream art world interests and they have received little critical attention. This
paper examines the development of Rapoport’s images and places her use of chemical references in context in her lifetime of
work.
相似文献
Meredith TrombleEmail: |
9.
E. Santos A. Lundin K. Pötting P. Quaino W. Schmickler 《Journal of Solid State Electrochemistry》2009,13(7):1101-1109
Due to progress in the theory of electrocatalysis and in quantum chemistry, it has become possible to investigate the hydrogen
reaction and perform quantitative calculations for the reaction rate. First, we demonstrate this with model calculations for
the adsorption of hydrogen on Pt(111). In accordance with experimental data, we find hydrogen adsorption at a potential above
the equilibrium potential and with an almost vanishing energy of activation. As a second example, we explain trends in the
catalytic activity of palladium overlayers and clusters on Au(111) electrodes.
Dedicated to J.O’M. Bockris on the occasion of his 85th birthday and in recognition of his contributions to electrochemistry.
相似文献
W. SchmicklerEmail: |
10.
Michael Noyong Buelent Ceyhan Christof M. Niemeyer Ulrich Simon 《Colloid and polymer science》2006,284(11):1265-1273
The formation and the optical features of two-dimensional aggregates formed by DNA-directed immobilization and cross-linking of bifunctional DNA–gold nanoparticles at flat gold substrates are analyzed. The samples are structurally characterized by atomic force microscopy to evaluate the particle size, the particle densities, and the degree of aggregation. The optical characteristics determined by UV/visible measurements are correlated with the structural features observed.
相似文献
Ulrich SimonEmail: |
11.
Ernesto Paparazzo 《Foundations of Chemistry》2008,10(1):63-75
This paper analyzes views of the Stoic philosopher Posidonius (1st century BC) in the light of modern Chemistry. I propose
that Posidonius’ account on “generation and destruction” bears noteworthy similarities to the scientific notions of chemical
elements, chemical species, nuclear reactions, and the law of conservation of mass. I find that his views compare favorably
also with our understanding of chemical change at solid surfaces. Provided his thought is correctly placed in the cultural
context of his day, I argue that Posidonius deserves a previously un-acknowledged consideration in the historical background
of modern Chemistry.
相似文献
Ernesto PaparazzoEmail: |
12.
Guy Yardeni Israel Zilbermann Eric Maimon Haim Cohen Dan Meyerstein 《Research on Chemical Intermediates》2009,35(4):543-554
A new CeIII complex was synthesized by mixing the ligand “dioxocyclam” with CeIII ions at pH 8.0 and its redox properties were investigated.
相似文献
Dan Meyerstein (Corresponding author)Email: |
13.
René Dybkaer 《Accreditation and quality assurance》2007,12(12):661-663
Terminology within a small laboratory community can be informal without danger of misunderstanding, but communication with
a wider audience and not least in publications, needs unequivocal terms for defined concepts. As an example, the many meanings
of “concentration” are explored to present a systematic nomenclature, including a concept diagram.
相似文献
René Dybkaer |
14.
N. Sukumar 《Foundations of Chemistry》2009,11(1):7-20
The concept of molecular structure is fundamental to the practice and understanding of chemistry, but the meaning of this
term has evolved and is still evolving. The Born–Oppenheimer separation of electronic and nuclear motions lies at the heart
of most modern quantum chemical models of molecular structure. While this separation introduces a great computational and
practical simplification, it is neither essential to the conceptual formulation of molecular structure nor universally valid.
Going beyond the Born–Oppenheimer approximation introduces new paradigms, bringing fresh insight into the chemistry of fluxional
molecules, proteins, superconductors and macroscopic dielectrics, thus opening up new avenues for exploration. But it requires
that our ideas of molecular structure need to evolve beyond simple ball-and-stick-type models.
相似文献
N. SukumarEmail: |
15.
The objective of this paper is to provide an economic perspective to those involved in public financing of the national metrology
infrastructure. Whereas justifications for subsidising the national metrological activities are often historically biased,
we raise the importance of economic considerations, which could be used during prioritisation. The expenditure in measurement
and metrology infrastructure of European countries are compared to economic indicators for quality of life. Various proxies
are used, such as measuring instruments sale (for measurement infrastructure) and data from the BIPM’s KCDB (as a proxy for
national standards). As the EU Internal Market also holds for the provision of metrological services, the paper exposes possible
trends regarding public financing to the sector.
相似文献
Nineta MajcenEmail: |
16.
René Dybkaer 《Accreditation and quality assurance》2007,12(10):553-557
Laboratory medicine provides results for quantities as well as for properties having no magnitude. The terminology of the
latter is less well established and sources are contradictory. Two recent papers on “protometrology” published in this journal
offer an opportunity to discuss the necessary concept systems. The delineations of “metrology” versus “protometrology”, “observation”
versus “measurement”, and the generic division of “property” are examined with emphasis on avoiding conflict with the International
Vocabulary of Metrology. It is suggested that having “examination” as a top generic concept coupled with systematic modifiers
for division, especially ‘nominal’ and ‘ordinal’, is a preferable terminological solution.
相似文献
René Dybkaer |
17.
Micah Newman 《Foundations of Chemistry》2008,10(1):49-62
This paper surveys some ways in which the chemical realm can be described and outlined in terms of the concept of supervenience.
The particular contours of general chemical theory provide a ready basis for interpretation of determination, covariance,
and nonreduction—the characteristic metaphysical facets of the supervenience relation—in mutual terms. Building on this, the
extent to which chemically characterized properties and entities can be described in terms of a supervenience-scaffolded structure
represents a particularly vivid application that philosophers in general interested in supervenience would do well to attend
to. In addition, the model of chemical supervenience given here can be used as a rubric on which to decide on issues already
raised by philosophers of chemistry.
相似文献
Micah NewmanEmail: |
18.
Xavier Fuentes-Arderiu 《Accreditation and quality assurance》2006,11(12):640-643
Protometrology is a new term recently proposed to designate the science of observation. As any field of knowledge needs a
terminological system, in this article a system of terms and definitions on protometrology, with examples belonging to clinical
laboratory sciences, is presented. This terminological system starts with the definitions of the two primitive concepts “object”
and “property”.
相似文献
Xavier Fuentes-ArderiuEmail: |
19.
Yan Gao Sabrina Reischmann Johannes Huber Tobias Hanke Rudolf Bratschitsch Alfred Leitenstorfer Stefan Mecking 《Colloid and polymer science》2008,286(11):1329-1334
Single semiconductor quantum dots were embedded into polymer particles with diameters below 0.1 μm by an emulsion polymerization
procedure or via a secondary dispersion approach. The photoluminescence properties of the nanocrystals are retained upon encapsulation,
as demonstrated by fluorescence confocal microscopy.
相似文献
Stefan MeckingEmail: |
20.
Alan F. Chalmers 《Foundations of Chemistry》2008,10(3):157-166
This paper suggests that the cases made for atoms and the aether in nineteenth-century physical science were analogous, with
the implication that the case for the atom was less than compelling, since there is no aether. It is argued that atoms did
not play a productive role in nineteenth-century chemistry any more than the aether did in physics. Atoms and molecules did
eventually find an indispensable home in chemistry but by the time that they did so they were different kinds of entities
to those figuring in the speculations of those natural philosophers who were atomists. Advances in nineteenth-century chemistry
were a precondition for rather than the result of the productive introduction of atoms into chemistry.
相似文献
Alan F. ChalmersEmail: |