A Letter Signed: The Very Beginnings of Dalton's Atomic Theory

Abstract

This paper explores the provenance and content of a previously unknown personal letter by John Dalton (1766–1844), which is dated 12 April 1803. It relates to a startling breakthrough in Dalton's research, which pre-dates by five months the earliest date in his laboratory notebook, namely, 6 September 1803. The author acquired the letter about thirty years ago, and now offers it to the public. He makes no attempt to explain how it contributes to — or even changes — our understanding of Dalton, but leaves that privilege to Dalton scholars.     

Dalton’s Disputed Nitric Oxide Experiments and the Origins of his Atomic Theory

In 1808 John Dalton published his first general account of chemical atomic theory, a cornerstone of modern chemistry. The theory originated in his earlier studies of the properties of atmospheric gases. In 1803 Dalton discovered that oxygen combined with either one or two volumes of nitric oxide in closed vessels over water and this pioneering observation of integral multiple proportions provided important experimental evidence for his incipient atomic ideas. Previous attempts to reproduce Dalton’s experiments have been unsuccessful and some commentators have concluded the results were fraudulent. We report a successful reconstruction of Dalton’s experiments and provide an analysis exonerating him of any scientific misconduct. But we conclude that Dalton, already thinking atomistically, adjusted experimental conditions to obtain the integral combining proportions.     

Activation of heterogeneous catalysts by organoaluminium compounds

The catalytic (benzene hydrogenation) and adsorption (O₂, CO) properties of NiO/Al₂O₃ and Ni(C₅H₇O₂)₂/Al₂O₃ reduced by trimethylaluminium and hydrogen have been studied. Significant differences in their catalytic and adsorption properties have been observed. The increased hydrogenation activity of catalysts reduced by trimethylaluminium is due to the increased reduction degree and dispersity of the active component.

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( ) (O₂, CO) NiO/Al₂O₃ Ni(C₅H₇O₂)₁/Al₂O₃, H₂. . , , .

     

Etienne Francois Geoffroy's table of relations and the concept of affinity

Summary The paper describes Geoffroy's table of proportions. The context in which it was developed is discussed, and subsequent tables, particularly those of Bergman, are dealt with at some length. The impact that such tables, known as affinity tables, had during the 18th century, and the reasons of their vogue receding with the birth of modern chemistry at the time of Lavoisier and Dalton are analysed.     

Characterization of humic and fulvic acids from Gorleben groundwater

Summary The humic material extracted from one of the Gorleben groundwaters is separated into humic and fulvic acids, and characterized, together with a commercial humic acid from Aldrich Co., for their chemical composition, size distribution, proton exchange capacity and spectroscopic characteristics. The results are compared with one another and with the literature data of other humic acids. The humic acid is fractionated by gel permeation chromatography into different size groups and the fractions are subjected to IR and ¹H-NMR spectroscopy. The high molecular weight fractions (>70000 Dalton) are poor in carboxylic groups, whereas the major fractions (approx. 10000 Dalton) contain organic acids of large molecular entities.     

Effect of surface covering of lactose carrier particles on dry powder inhalation properties of salbutamol sulfate

The effect of the surface covering of lactose carrier particles on the dry powder inhalation properties of salbutamol sulfate was investigated. Lactose carrier surfaces were covered with sucrose tristearate (J-1803F) by a high-speed elliptical-rotor-type powder mixer (Theta-Composer). In the present study, drug/carrier powder mixtures were prepared consisting of micronized salbutamol sulfate and lactose carriers with various particle surface conditions prepared by surface covering. These powder mixtures were aerosolized by a Jethaler), and the in vitro inhalation properties of salbutamol sulfate were evaluated by a twin impinger. Compared with the powder mixed with uncovered lactose carrier, the in vitro inhalation properties of the powder mixture prepared using the surface covering lactose carrier were significantly different, showing that the in vitro inhalation properties of salbutamol sulfate were improved. In vitro inhalation properties increased with the percentage of J-1803F added. Using this surface covering system would thus be valuable for increasing the inhalation properties of dry powder inhalation with lactose carrier particles.     

Molar mass determination of macromolecular compounds by matrix-assisted laser desorption ionization mass spectrometry

Matrix-assisted laser desorption ionization is a recently developed new ionization technique which enables macromolecular compounds to be investigated by mass spectrometry. The general features of the technique are described, they have so far mainly been worked out for biopolymers such as proteins. Fast and precise molecular weight determination is possible up to 400,000 Dalton. First examples described in this paper indicate that the technique also holds great promise for the investigation of synthetic polymers.     

In memory of Mikhail V. Volkenshtein

Dedicated to the 90^th anniversary of his birth and to 10 years after his death. Professor and Associated Member of the USSR Academy of Sciences Mikhail V. Volkenshtein was an outstanding scientist well known by his work in physics, chemistry, and biophysics. Two scientific sessions of this Symposium were dedicated to the memory of this great scientist and opened with the lecture of Tatiana M. Birshtein. In the archive of T. M. Birshtein there is a letter by M. V. Volkenshtein, which was written in 1982 in reply on her request to present some necessary information for the paper in Polymer Science (Russia) dedicated to the 70^th anniversary of his birth. This letter gives one a good idea about both the scientific activity and bright personality of the author. T. M. Birshtein and A. A. Mercurieva translated the document and prepared this publication. The main text of the letter is below, it is typed by Italic to be distinguished from the comments.     

Metal-based antitumour drugs in the post-genomic era: what comes next?

In our Dalton Transactions Perspective article entitled, 'Metal-based antitumour drugs in the post genomic era', (Dalton Trans., 2006, 1929-1933) we discussed metal-based drugs in light of past decades of research. We concluded that the post-genomic era would dictate a change in the direction of the field with knowledge of the genome increasingly allowing protein targets to be identified and not simply assuming that DNA is the only relevant target of metal-based drugs. Since our article was published new insights into the mode of action of metal-based drugs have emerged making some older findings increasingly relevant to current drug design. In this article we discuss these developments in terms of what we believe should be the future direction for the field.     

On the connections between the quantum theory of atoms in molecules (QTAIM) and density functional theory (DFT): a letter from Richard F. W. Bader to Lou Massa

A 31-year-old letter from Professor Richard F. W. Bader to Professor Lou Massa outlining the connections between the quantum theory of atoms in molecules (QTAIM) and density functional theory (DFT) especially with regard to the first Hohenberg-Kohn theorem is brought to light. This connection has not often been the topic of such a focused review by Bader and is presented here for the first time. The scientific importance of this letter is, in the opinion of the presenter, as timely today as it was back then in 1986. In Bader’s own opening words: “... that if I sent you a summary of what I think are the important connections between our work and density functional theory, ...”. He then takes us in a grand tour of the foundations of QTAIM culminating into the antecedents of a paper he later published with Professor Pierre Becker, whereby the Hohenberg-Kohn theorem is shown to operate at the level of an atom-in-a-molecule. Bader closes his letter by suggesting to Massa: “Study these two charge distributions – they are proof of the theorem of Hohenberg and Kohn”. By that Bader meant that when the charge distributions of two atoms or groups are identical within a given precision, then the kinetic and total energy contributions of these atoms to the corresponding molecular quantities are also identical. It is revealing to follow the intellectual threads weaved by Bader which provides us with a glimpse of his thought processes and intuition that guided him to some of his key discoveries. The lucidity, rigor, and clarity characteristic of Bader and the informality of style of a letter makes it of pedagogic and historic interest.

     

Determination of the Chemical Structure of Poly-β (-)-pinene by NMR Spectroscopy

This paper is dedicated to the memory of our friend and colleague Annalaura Segre.

The chemical structure of a series of β (-)-pinene polymers (PBP) obtained by radiation-induced polymerization, free radical initiation, cationic polymerization over a Friedel-Craft catalyst and by coordinative polymerization over a Ziegler-Natta catalyst has been fully elucidated by ¹H and ¹³C-NMR spectroscopy. 2D NMR techniques have been applied in order to assign all the NMR resonances to the structures of the PBP investigated. The NMR spectra show that the most regular PBP structure is obtained by radiation-induced polymerization followed by the free radical initiated polymerization. The most defective structure has been observed in the case of PBP prepared by cationic mechanism over a Friedel-Crafts catalyst. The discussion accounts for different types of defects and cross-links present in the PBPs investigated whose fundamental structure is based on the p-menthene repeating unit.

NMR self-diffusion measurements have been performed to evaluate the molecular weight of all the PBP investigated. The highest molecular weight (2600 Dalton) was found in the case of PBP prepared by Ziegler-Natta catalyst, while the lowest molecular weight was found in the case of PBP prepared by radiation-induced polymerization (about 1000 Dalton).     

Nanosize metallodendrimers

Building blocks have been designed for the non-covalent formation of nanosize assemblies. As non-covalent interactions coordination chemistry and hydrogen bonding have been used. The self-assembly process leads to spherical assemblies with diameters in the range of 100 to 400 nm, with standard deviations in the order of 10–15%. The controlled assembly approach allows a precise controll of size and assemblies with molecular weights up to 10,000 Dalton have been realized. Finally, we have developed a strategy in which hydrogen bonding and coordination chemistry can be applied “orthogonally”     

Gender Diversity in a STEM Subfield – Analysis of a Large Scientific Society and Its Annual Conferences

Speaking engagements, serving as session chairs, and receiving awards at national meetings are essential stepping stones towards professional success for scientific researchers. Studies of gender parity in meetings of national scientific societies repeatedly uncover bias in speaker selection, engendering underrepresentation of women among featured presenters. To continue this dialogue, we analyzed membership data and annual conference programs of a large scientific society (>7000 members annually) in a male-rich (~70% males), technology-oriented STEM subfield. We detected a pronounced skew towards males among invited keynote lecturers, plenary speakers, and recipients of the society’s Senior Investigator award (15%, 13%, and 8% females, respectively). However, the proportion of females among Mid-Career and Young Investigator award recipients and oral session chairs resembled the current gender distribution of the general membership. Female members were more likely to present at the conferences and equally likely to apply and be accepted for oral presentations as their male counterparts. The gender of a session chair had no effect on the gender distribution of selected applicants. Interestingly, we identified several research subareas that were naturally enriched (i.e., not influenced by unequal selection of presenters) for either female or male participants, illustrating within a single subfield the gender divide along biology-technology line typical of all STEM disciplines. Two female-enriched topics experienced a rapid growth in popularity within the examined period, more than doubling the number of associated researchers. Collectively, these findings contribute to the contemporary discourse on gender in science and hopefully will propel positive changes within this and other societies.

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Debye temperatures from ESR

A recent letter by Shrivastava, entitled “Evaluation of Debye Temperatures as a New Application of Electron-Spin Resonances” is discussed. It is argued that this letter may give rise to unwarranted optimism regarding this method, which is probably more useful for the investigation of the substitutional process.     

A proteomic analysis of erythromycin resistance in Streptococcus pneumoniae.

Streptococcus pneumoniae is a significant human pathogen which is an important cause of pneumonia and bacteraemia. Over the past few years the incidence of antibiotic resistance among clinical isolates of S. pneumoniae has increased. Penicillin resistance is now widespread and the frequency of isolates that are resistant to erythromycin has risen. Erythromycin resistance in S. pneumoniae follows two basic patterns. The MLS erythromycin-resistant phenotype is due to the enzymatic methylation of ribosomal RNA that blocks erythromycin binding to the ribosome. Alternatively, in isolates of the M phenotype, a more recently documented mechanism, resistance is associated with an active efflux process that reduces intracellular levels of erythromycin. We used two-dimensional electrophoresis to examine the proteins synthesised by erythromycin-susceptible and -resistant S. pneumoniae. Erythromycin-resistant S. pneumoniae with the M phenotype showed a significantly increased synthesis of a 38,500 Dalton (pI 6.27) protein compared to susceptible isolates. Peptide mass mapping was used to identify the 38,500 Dalton protein as glyceraldehyde-3-phosphate dehydrogenase (GAPDH). It was demonstrated that S. pneumoniae synthesised at least three forms of GAPDH that differed in their isoelectric points. The form of GAPDH possessing the most basic pI showed the increased synthesis in the erythromycin-resistant S. pneumoniae isolates. Alterations in the synthesis of GAPDH were only found for those erythromycin-resistant isolates possessing the M phenotype. S. pneumoniae isolates with the MLS phenotype were indistinguishable from the susceptible strains using the analytical conditions employed for the current study. The possible role of GAPDH in erythromycin resistance of S. pneumoniae is considered.     

Reactions of 1,3-alkadiynes (n > 4) with secondary amines

Conclusions A study was made of some regular features of the addition of secondary amines to 1,3-alkadiynes with more than four carbons in the chain.This article is published in accordance with a resolution of the Conference of Editors-in-Chief of Journals of the USSR Academy of Sciences of July 12, 1962, as a dissertation paper by E. A. Él'perina.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 1803–1806, October, 1966.     

Multiply charged ions in ionspray tandem mass spectrometry

Multiply charged anions of some 30 species containing multiple carboxylic, sulphonic and/or phosphoric groups generated by ionspray were studied by using tandem mass spectrometry (MS/MS). Two trends emerged: (1) lower-charged ions are preferentially evaporated, and (2) for more highly charged ions, evaporability is a function of ion size. Triply and quadruply charged ions were observed for azo dyes with molecular masses in the 700-900 Dalton range. Daughter-ion mass spectra of selected multiply charged ions are presented.     

Fast and convenient divergent synthesis of aliphatic ester dendrimers by anhydride coupling.

A novel divergent approach was developed for the synthesis of dendritic aliphatic polyester structures using an acetal-protected anhydride derivative of 2,2-bis(hydroxymethyl)propionic acid as the acylating agent. This divergent synthesis is remarkable, because unlike all others, it only requires a small excess of reagent to achieve quantitative growth, and it requires no means of purification other than a simple solvent extraction or precipitation. A monodisperse sixth generation dendrimer with molecular weight of 30 711 Dalton and 192 masked hydroxyl groups was prepared in high yield and purity using 1,1,1-tris(hydroxyphenyl)ethane as the core molecule. Linear and star-shaped poly(ethylene glycol) (PEG) derivatives of narrow polydispersity were also used as core molecules in the divergent synthesis of dendritic-linear copolymer hybrids up to the fourth generation without requiring any chromatographic purification.     

Approximate methods for the fast computation of EPR and ST-EPR spectra. V. Application of the perturbation approach to the problem of anisotropic motion

The modulation perturbation treatment of Galloway and Dalton is applied to the solution of the stochastic Liouville equation for the spin density matrix which incorporates an anisotropic rotational diffusion operator. Pseudosecular and saturation terms of the spin hamiltonian are explicitly considered as is the interaction of the electron spins with the applied Zeeman modulation field. The modulation perturbation treatment results in a factor of four improvement in computational speed relative to inversion of the full supermatrix with little or no loss of computational accuracy. The theoretical simulations of EPR and ST-EPR spectra are in nearly quantitative agreement with experimental spectra taken under high resolution conditions.     

An Aptamer‐Nanotrain Assembled from Six‐Letter DNA Delivers Doxorubicin Selectively to Liver Cancer Cells

Expanding the number of nucleotides in DNA increases the information density of functional DNA molecules, creating nanoassemblies that cannot be invaded by natural DNA/RNA in complex biological systems. Here, we show how six‐letter GACTZP DNA contributes this property in two parts of a nanoassembly: 1) in an aptamer evolved from a six‐letter DNA library to selectively bind liver cancer cells; and 2) in a six‐letter self‐assembling GACTZP nanotrain that carries the drug doxorubicin. The aptamer‐nanotrain assembly, charged with doxorubicin, selectively kills liver cancer cells in culture, as the selectivity of the aptamer binding directs doxorubicin into the aptamer‐targeted cells. The assembly does not kill untransformed cells that the aptamer does not bind. This architecture, built with an expanded genetic alphabet, is reminiscent of antibodies conjugated to drugs, which presumably act by this mechanism as well, but with the antibody replaced by an aptamer.