Numbers,scale and symbols: the public understanding of nanotechnology

Nanotechnology will be an increasing part of the everyday lives of most people in the world. There is a general recognition that few people understand the implications of the technology, the technology itself or even the definition of the word. This lack of understanding stems from a lack of knowledge about science in general but more specifically difficulty in grasping the size scale and symbolism of nanotechnology. A potential key to informing the general public is establishing the ability to comprehend the scale of nanotechnology. Transitioning from the macro to the nanoscale seems to require an ability to comprehend scales of one-billion. Scaling is a skill not common in most individuals and tests of their ability to extrapolate size based upon scaling a common object demonstrates that most individuals cannot scale to the extent needed to make the transition to nanoscale. Symbolism is another important vehicle to providing the general public with a basis to understand the concepts of nanotechnology. With increasing age, individuals are able to draw representations of atomic scale objects, but these tend to be iconic and the different representations not easily translated. Ball and stick models are most recognized by the public, which provides an opportunity to present not only useful symbolism but also a reference point for the atomic scale.     

Orlicz norm estimates for eigenvalues of matrices

Let φ be a supermultiplicative Orlicz function such that the function $t \mapsto \varphi \left( {\sqrt t } \right)$ is equivalent to a convex function. Then each complexn×n matrixT=(τ _ij ) _{i, j} satisfies the following eigenvalue estimate: $\left\| {\left( {\lambda _i \left( T \right)} \right)_{i = 1}^n } \right\|_{\ell _\varphi } \leqslant C\left\| ( \right\|\left( {\tau _{ij} } \right)_{i = 1}^n \left\| {_{_{\ell _{\varphi *} } } )_{j = 1}^n } \right\|\ell _{\bar \varphi } $ . Here, ?_* stands for Young’s conjugate function of φ, ?, $\bar \varphi $ is the minimal submultiplicative function dominating φ andC>0 a constant depending only on φ. For the power function φ(t)=t ^p ,p≥2 this is a celebrated result of Johnson, König, Maurey and Retherford from 1979. In this paper we prove the above result within a more general theory of related estimates.     

A Graded Quadrivalent Logic for Ordinal Preference Modelling: Loyola–Like Approach

We extend a quadrivalent logic of Belnap to graded truth values in order to handle graded relevance of positive and negative arguments provided in preferential information concerning ranking of a finite set of alternatives. This logic is used to design the preference modelling and exploitation phases of decision aiding with respect to the ranking problem. The graded arguments are presented on an ordinal scale and their aggregation leads to preference model in form of four graded outranking relations (true, false, unknown and contradictory). The exploitation procedure combines the min-scoring procedure with the leximin rule. Aggregation of positive and negative arguments as well as exploitation of the resulting outranking relations is concordant with an advice given by St. Ignatius of Loyola (1548) how to make a good choice.     

Validation of a simple liquid chromatographic method for determination and quantitation of residual ivermectin and doramectin in pig liver

A rapid and quantitative method for the extraction, derivatization, and liquid chromatography with fluorescence detection of ivermectin (IVM) and doramectin (DOM) residues in porcine liver was developed and validated. IVM and DOM were extracted from the liver samples with acetonitrile, the supernatant was evaporated to dryness at 37 degrees C under nitrogen, and the residue was reconstituted in 1-methylimidazole solution. After 2 min at room temperature, IVM and DOM were converted to a fluorescent derivative and then separated on a Hypersil ODS column. The derivatives of IVM and DOM were detected and quantitated with high specificity by fluorescence (excitation: 365 nm, emission: 475 nm). Abamectin was used as an internal standard. The mean extraction efficiencies from fortified samples (15 ng/g) were 75% for IVM and 70% for DOM. The limit of detection was 0.8 ng/g for both IVM and DOM.     

Apparent Molar Volumes of Multicharged Cations in Dimethyl Sulfoxide Solutions at 25°C

Densities for DMSO solutions of iron(III), aluminium(III), beryllium(II) and magnesium(II) perchlorates and silver nitrate are reported. Densities for DMSO solutions of tetraethylammonium perchlorate and nitrate and tetrabutylammonium perchlorate and tetraphenylborate are also presented. The partial molar volumes of the DMSO-solvated cations are derived and discussed in terms of variation with the charge number.     

Investigation of ion-pair precipitates of selected alkoxylates and complex salts of specific metal cations by liquid secondary ion mass spectrometry

Liquid secondary ion (LSI) mass spectra of ion-pair precipitates obtained for Triton X-100 with strontium, lead, cadmium and mercury tetraphenylborates and for selected butoxylene-ethoxylene monoalkyl ethers with barium tetraiodobismuthate(III) are discussed. On the basis of LSI mass spectra, recorded in both positive and negative modes, the formulae of the ion-pair precipitates were determined. On the basis of B/E mass spectra, the fragmentation routes of [M - H + Ba](+) ions for butoxylene-ethoxylene monoalkyl ether complexes of barium and [M - H + Cd](+) ions for the Triton X-100 complex of cadmium are proposed.     

Functionalized heteropolyanions: high-valent metal nitrido fragments incorporated into a Keggin polyoxometalate structure

Three examples of nitrido-functionalized polyoxometalate species are reported, namely (n-Bu4N)4[PW11O39(OsN)] (1), (n-Bu4N)4[PW11O39(ReN)] (2), and (n-Bu4N)3[PW11O39(ReN)] (3), which feature the incorporation of [OsVI identical to N]3+, [ReVI identical to N]3+ and [ReVII identical to N]4+ fragments, respectively, into the framework of a Keggin-type heteropolyanion.     

Sustainable photochemistry: solvent-free singlet oxygen-photooxygenation of organic substrates embedded in porphyrin-loaded polystyrene beads

A solvent-free photooxygenation process that uses organic substrates embedded in porphyrin-loaded polystyrene beads as solid support is described and applied for ene- and [4 + 2]-cycloaddition reactions involving singlet oxygen (1 delta g).     

Retention of configuration in the action of human plasma 3'-exonuclease on oligo(deoxynucleoside phosphorothioate). A new method for assignment of absolute configuration at phosphorus in isotopomeric deoxyadenosine 5'-O-[(18)O]phosphorothioate

A new method of analysis has allowed the exonucleolytic cleavage by human 3'-exonuclease to be determined. Hydrolysis by human plasma 3'-exonuclease proceeds with retention of configuration at phosphorus. The new method determines the sense of chirality at phosphorus in isotopomeric adenosine 5'-O-[(18)O]phosphorothioates. This is based on stereospecific two-step conversion of the mono-thionucleotide into the corresponding deoxyadenosine 5'-O-alpha-[(18)O]thiotriphosphate, followed by the use of terminal deoxyribonucleotidyl transferase and MALDI TOF mass spectrometry of the resulting elongated primer. Retention of configuration in the reaction of plasma 3'-exonuclease implies a two-step mechanism with two displacements on phosphorus. Inversion at each step leads to overall retention.