(1983). Hydrogen production for ballooning during the French Revolution: An early example of chemical process development. Annals of Science: Vol. 40, No. 6, pp. 531-558.

The hydrogen market in the world today is capable ovule and empirical evidence on activity of patents in fuel cells and hydrogen production is limited so far. Patent applications in zero-emission mobility in the aspect of fuel cells include: DAFC/dmfc&dmfc, PEMFC, SOFC, AFC, PAFC. As for the patents relating to the hydrogen production, they concern low carbon, electrolysis and inorganic. The purpose of the study was to investigate certain aspects of the activity of patents in (...) fuel cells and hydrogen production in the context of passenger car fleet in the Visegrad group (V4) countries and to explore the relationship between patent registrations and GDP per capita in V4. The research area relates to the answer to the question of whether a country’s involvement in zero-emission patent activity (patents in fuel cells and hydrogen production) could contribute to the renewal of the country’s passenger car fleet. The theses were formulated as follows: 1) activity of patents in fuel cells and hydrogen production in the V4 countries doesn’t depend on the car fleet in these countries, 2) the level of GDP per capita in the V4 countries is not followed by the number of patents registrations in hydrogen technology, 3) the highest patent activity in fuel cells and hydrogen production doesn’t mean that the car fleet in these country will be zero-emission in coming years. The method used in this article is a comparative analysis, but also the relationships between patent registrations, GDP per capita and passenger car fleet in V4 are considered. (shrink)

Hydrogen energy systems are being developed to replace fossil fuels–based systems for transportation and stationary application. One of the challenges facing the widespread adoption of hydrogen as an energy vector is the lack of an efficient, economical, and sustainable method of hydrogen production. In the short term, hydrogen produced from fossil fuels will facilitate a transition to the hydrogen economy. In the long term, renewable hydrogen production methods will have to be adopted (...) as resources become scarce, causing the price of fossil fuels to rise. In this work, a number of methods have been considered for the renewable production of solar hydrogen, and thermochemical sulphur-iodine cycles proved to be the most promising. The sulphur-iodine cycles have the highest efficiencies and use widely available reactants with relatively straightforward reaction mechanisms, which make them the most economical and technically feasible option for renewable hydrogen production. (shrink)

Hydrogen is a very important industrial gas in chemical processes. It is very volatile; therefore, it can escape from the process units and its mass balance is not always correct. In many industrial processes where hydrogen is reacted, kinetics are often related to hydrogen pressure. The right thermodynamic properties of hydrogen can be found for a process simulation and optimization; they can be estimated by the Grayson-Streed model. In the case studied, a methanol plant with a (...) capacity of 150,000 tons/year, the flow rate of hydrogen (H2) can be optimized using nonlinear programming, but good estimates of thermodynamic properties of hydrogen had to be found. In the case study, the model is in relatively good agreement with experimental measurements in the existing methanol production plant. An additional flow rate of hydrogen can increase the methanol production by 1.2%. Total potential profit increase of the additional methanol production was estimated to be 30 kEUR/a (or 103 euros/year). (shrink)

An economically viable and environmental friendly method of generating hydrogen for fuel cells is by the reaction of certain metals with steam, called metalsteam reforming (MSR). This technique does not generate any toxic by-products nor contributes to the undesirable greenhouse effect. From the standpoint of favorable thermodynamics, total environmental benignity, and attractive economics, iron appears to be the metal of choice for such a process. An inexpensive source of iron for the MSR is the steel industry's mill-scale waste via (...) hydrogen and carbothermic reduction, both of which are energy-intensive processes. These have been eliminated by a novel, solution-based room temperature technique producing nanoscale iron, thus obviating the sintering of iron or iron oxide and deactivation during the cyclic operation of MSR. Some preliminary results are presented of an investigation aimed at converting the mill-scale waste into nanoscale iron, which was subsequently used in generating hydrogen for proton exchange membrane fuel cells. (shrink)

An existing industrial hydrogen generation and distribution infrastructure is described, and a number of large-scale investment projects are outlined. All of these projects have the potential to generate significant volumes of low-cost, low-carbon hydrogen. The technologies concerned range from gasification of coal with carbon capture and storage to gasification of a range of biomass streams. These biomass streams derive in turn from the supply chains that feed large liquid biofuel production plants—some operational and the others under construction. (...) Having described how such developments are coming together in a particular location to allow accelerated movement toward a hydrogen economy, this article explores the conditions under which similar acceleration could be seen in other locations. (shrink)

In this article, a number of future energy visions, especially those basing the energy systems on hydrogen, are discussed. Some often missing comparisons between alternatives, from a sustainability perspective, are identified and then performed for energy storage, energy transportation, and energy use in vehicles. It is shown that it is important to be aware of the losses implied by production, packaging, distribution, storage, and end-use of hydrogen when suggesting a “hydrogen economy.” It is also shown that (...) for stationary electric energy storage, fuel cell electrolyzers could be feasible. Zero-tailpipeemission vehicles are compared. The battery electric vehicle has the highest electrical efficiency, but other requirements imply that plug-in hybrids or fuel cell hybrids might be a better option in some types of vehicles. Finally, a simplified example is applied to the overall results and used to discuss the needs and nature of an energy system based on intermittent energy sources. (shrink)

Traditional nomological accounts of scientific explanation have assumed that a good scientific explanation consists in the derivation of the explanandum’s description from theory (plus antecedent conditions). But in more recent philosophy of science the adequacy of this approach has been challenged, because the relation between theory and phenomena in actual scientific practice turns out to be more intricate. This critique is here examined for an explanatory paradigm that was groundbreaking for 20th century physics and chemistry (and their interrelation): Bohr’s first (...) model of the atom and its explanatory relevance for the spectrum of hydrogen. First, the model itself is analysed with respect to the principles and assumptions that enter into its premises. Thereafter, the origin of the model’s explanandum is investigated. It can be shown that the explained “phenomenon” is itself the product of a host of modelling accomplishments that stem from an experimental tradition related to 19th century chemistry, viz. spectroscopy. The relation between theory and phenomenon is thus mediated in a twofold way: by (Bohr’s) theoretical model and a phenomenological model from spectroscopy. In the final section of the paper an account is outlined that nevertheless permits us to acknowledge this important physico-chemical achievement as a case of (nomological) explanation. (shrink)

Japan is a country largely lacking supplies of many essential natural resources including petroleum, coal, and iron ore. As her industrial base and economy expanded during the 1920s and 1930s, Japan's dependence on imports of these resources became increasingly evident. The onset of the Depression in the 1930s further threatened Japan's lifeline, and, in an effort to become economically independent and self-sufficient in natural resources , Japan's militaristic government pursued a policy of territorial expansion. Beginning in 1937, Japan's military forces (...) swept out of Manchuria into China and then into Southeast Asia in search of strategic materials such as petroleum, coal, copper, zinc, and rubber. To achieve independence in petroleum, the Japanese developed a dual approach: they would acquire natural petroleum sources in Southeast Asia and at the same time establish a synthetic fuel industry for the conversion of coal to oil. Actually, the Japanese had begun research on synthetic fuel in the 1920s, only a few years after other countries, such as Germany and Britain, that lacked sources of natural petroleum. They did excellent laboratory research on the coal hydrogenation and Fischer-Tropsch conversion processes, but in their haste to construct large synthetic fuel plants they bypassed the intermediated pilot-plant stage and failed to make a successful transition from small- to large-scale production. Unable to synthesize liquid fuels from coal, they instead derived significant quantities from the technologically simpler coal carbonization and shale oil distillation processes. In the last year of World War II, the Japanese attempted to revive their synthetic fuel industry and entered into an agreement with IG Farben for technical assistance. Germany's defeat ended this final effort. The Japanese synthetic fuel industry presents a good case study of technological failure. It shows that high-quality basic scientific research does not necessarily translate into large-scale technological success. (shrink)

This work presents results of improvement in the productivity of Arthrospira platensis in a company dedicated to its production. The six sigma methodology was applied in production processes that require the use of bioreactors. Starting from the analysis of the current state, aspects, physical and chemical variables that directly influence the productivity achieved were identified. Various culture media were tested and subsequently scaled for industrial production. In addition, the incorporation of carbon into the culture medium was controlled, (...) optimizing the range of potential hydrogen pH. The identified parameters were measured and six sigma methodology strategies were assigned. An improvement in productivity corresponding to 66% was verified with the same quality of final product. Keywords: Six sigma, Bioreactors, Productivity, Arthrospira platensis. References [1]E. Ariawan and A. Makalew, “Smart Micro Farm: Sustainable Algae Spirulina Growth Monitoring System” in 10th International Conference on Information Technology and Electrical Engineering, Bali, 2018, pp.1-4. [2]L. Socconini and C. Reato, Lean six sigma: sistema de gestión para liderar empresas. Primera edición. Barcelona: Marge Books, 2019. [3]H. Gutiérrez, Calidad and productividad. Cuarta edición. México D.F.: McGraw-Hill Interamericana, 2014. [4]G. Usharani, P. Saranraj and D. Kanchana, “Spirulina Cultivation: A Review” in International Journal of Pharmaceutical & Biological Archives, vol. 3, no. 6, pp. 1327-1336, December 2012. [5]J. Udin, O. Gani, A. Mahato, I. Sakib and M. Rakiuzzaman, SPIRULINA PRODUCTION IN DIFFERENT PHOTOBIOREACTORS ON ROOFTOP, International Journal of Business, Social and Scientific Research, vol. 8, no. 1, pp. 15-19, January 2020. [6]M. Arredondo, Contabilidad y análisis de costos. Primera edición. México D.F.: Grupo Editorial Patria, 2015. [7]J. García, Contabilidad de costos. Cuarta edición. México D.F.: McGraw-Hill Interamericana, 2014. [8]L. Socconini, Certificación Lean Six Sigma Green Belt para la excelencia en los negocios. Primera edición. Barcelona: Marge Books, 2015. [9]A. Vian, Introducción a la Química Industrial. Segunda edición. Buenos Aires: Reverté, 2012. [10]S. Milton, Estadística para Biología y Ciencias de la Salud. Tercera edición. Madrid: McGraw-Hill Interamericana, 2014. (shrink)

The electronic and muonic hydrogen energy levels are calculated very accurately [1] in Quantum Electrodynamics (QED) by coupling the Dirac Equation four vector (c ,mc2) current covariantly with the external electromagnetic (EM) field four vector in QED’s Interactive Representation (IR). The c -Non Exclusion Principle(c -NEP) states that, if one accepts c as the electron/muon velocity operator because of the very accurate hydrogen energy levels calculated, the one must also accept the resulting electron/muon internal spatial and time coordinate (...) operators (ISaTCO) derived directly from c without any assumptions. This paper does not change any of the accurate QED calculations of hydrogen’s energy levels, given the simplistic model of the proton used in these calculations [1]. The Proton Radius Puzzle [2, 3] may indicate that new physics is necessary beyond the Standard Model (SM), and this paper describes the bizarre, and very different, situation when the electron and muon are located “inside” the spatially extended proton with their Centers of Charge (CoCs) orbiting the proton at the speed of light in S energy states. The electron/muon center of charge (CoC) is a structureless point that vibrates rapidly in its inseparable, non-random vacuum whose geometry and time structure are defined by the electron/muon ISaTCO discrete geometry. The electron/muon self mass becomes finite in a natural way due to the ISaTCOs cutting off high virtual photon energies in the photon propagator. The Dirac-Maxwell-Wilson (DMW) Equations are derived from the ISaTCO for the EM fields of an electron/muon, and the electron/muon “look” like point particles in far field scattering experiments in the same way the electric field from a sphere with evenly distributed charge “e” “looks” like a point with the same charge in the far field (Gauss Law). The electron’s/muon’s three fluctuating CoC internal spatial coordinate operators have eight possible eigenvalues [4, 5, 6] that fall on a spherical shell centered on the electron’s CoM with radius in the rest frame. The electron/muon internal time operator is discrete, describes the rapid virtual electron/positron pair production and annihilation. The ISaTCO together create a current that produce spin and magnetic moment operators, and the electron and muon no longer have “intrinsic” properties since the ISaTCO kinematics define spin and magnetic moment properties. (shrink)

Hydrogen fuel cells are likely to begin replacing conventional internal combustion engines as a power generation method for transportation applications in the near future. A life cycle analysis of a hydrogen fuel cell was performed to examine the major environmental impacts of such an engine in comparison with an internal combustion engine. To quantify the emissions, material consumption and energy consumption were identified by carrying out mass and energy balances, respectively. Wherever possible, a “well-to-wheel” approach was adopted to (...) identify all the processes involved. The size of the hydrogen fuel cell engine selected was 60 kW, which would power a small automobile weighing around 800 kg. This report briefly describes the materials and processes involved in assembling such an engine, with their respective environmental impacts. Different technologies to build a hydrogen economy also are discussed because hydrogen is an integral part of most fuel cell engines. The main conclusion is that if an environmentally sustainable system of hydrogen production is found, the use of hydrogen and, in turn, hydrogen fuel cell cars would be highly beneficial. Thus, the theoretical potential of fuel cells is great for environmental benefits, but practical applications might prove otherwise. (shrink)

In recent years, it becomes clear that ITER project in France, as one of the largest experimental fusion reactors underway, is far away from achieving net energy production. In this review article, we presented a short communication this week with Robert Neil Boyd, a senior physicist who happens to have his own working design of fusion reactor in the past. We hope that this transcript of our communication with him (as per 15-17th Nov. 2021) may be found useful for (...) younger scientists. (shrink)

The present paper covers technological changes in the coal mining process. Coal is the main domestic energy resource in Ukraine. In this context such issues as upgrading of conventional technologies and introduction of innovative developments need early solution. Technology is a driving force of strategic development of enterprises in all industries, including the mining. Technological aspects and their interrelation with competitiveness were explored and substantiated by I. Ansoff, who also identified three possible variability levels of technology: 'stable', 'productive' and 'changeable'. (...) 'Stable' technology is virtually unchangeable throughout the life cycle of demand. It is intrinsic to coal production as coal has been mined for centuries and in spite of changes in mining techniques, the demand for it is high enough. This technology originated approximately in the late 18th century when the first mines appeared in the Donets Basin. 'Productive' technology means the traditional one within which various innovations are introduced. In the early development period of the mining industry only pillar mining was used. Two new directions were subsequently developed: shortwall and longwall mining. Winning mechanization in European countries was achieved through development of longwall machines. The USA preferred shortwall mining of coal seams. The above mining alternatives were examined at Donbas mines, the results compared by such parameters as the number of workers and their labor capacity. The necessity of introduction and further improvement of 'manless' mining flow diagrams was substantiated. Some methods for roadway maintenance without repairs were described. The measures required for roadway maintenance without repairs under different conditions can be divided into a number of groups: ways of roadway protection, use of supports with improved yielding, an increased cross-sectional area and longitudinal section of workings during driving, reinforcement of seam bearing rock, application of mine overhead carriers. 'Changeable' technology comprises such unconventional techniques as underground gasification, hydrogenization and hydraulic coal mining by boreholes as well as ancillary recovery of methane gas. (shrink)

Reactive oxygen species (ROS) are highly reactive molecules produced in cells. So far, they have mostly been connected to diseases and pathological conditions. More recent results revealed a somewhat unexpected role of ROS in control of developmental processes. In this review, we elaborate on ROS in development, focussing on their connection to epithelial tissue morphogenesis. After briefly summarising unique characteristics of epithelial cells, we present some characteristic features of ROS species, their production and targets, with a focus on proteins (...) important for epithelial development and function. Finally, we provide examples of regulation of epithelial morphogenesis by ROS, and also of developmental genes that regulate the overall redox status. We conclude by discussing future avenues of research that will further elucidate ROS regulation in epithelial development. (shrink)

Nature's simplest atom and mother of all matter, hydrogen feeds the stars as well as interlaces the molecules of their biological descendants – to whom it ultimately whispers the secrets of quantum reality. Hydrogen’s most prevalent earthly guise lies within the composition of water. A slight electrical disturbance can split water into hydrogen and oxygen gas, resulting in diaphanous bubble clouds slowly rising towards the liquid’s surface. Though the founding fathers of electrochemistry posited that the mass of (...) liberated bubbles is directly proportional to the input voltage, certain modes of electrolysis release more energy than is spent. One such mode involves water’s Janus-faced capacity to react as either an acid or a base. Emanating from an array of electrodes at the bottom of a water-filled chamber, strings and strata of hydrogen bubbles meticulously trace their emergent surroundings. In addition to eddy formations incited by a bubble's rapid growth and subsequent detachment from the electrode surface, acoustic vibrations permeate the two-phase fluid. As the sonic frequency and amplitude rises, the hydrogen bubbles start to coalesce with one another. When the sound field reaches maximum intensity, it can trap bubbles within its antinodes. The vibrations are generated both by transducers and by the bubbles themselves, which emit frequencies ranging from the audible spectrum to as high as 800 kHz. A white laser sheet scans and illuminates the hydrogen bubble trajectories. Each quivering bubble-lens divides the white light into its constituent spectrum of colors. While scanning, the laser sheet also swiftly pulsates and thereby extends the perceivable resolution of micro-momentary bubble dynamics. Before it even begins to map out its vibratory environment, a bubble goes through various stages of spatio-temporal evolution. During the first phase of growth, a bubble nucleus inflates linearly with time. At the second stage, bubble growth is limited by the diffusion of gas within the liquid, causing its size to increase as the square root of time. The final phase before detachment is limited by the kinetics of dissolved gas production, causing the bubble to grow as the cube root of time.1 Beyond macroscopically observable bubbles, an expanse of nanobubbles hides within the water’s internal architecture. Some researchers presume that these nanobubbles of dissolved gas are the carriers of water’s magnetic ‘memory’, enabling electromagnetic fields to saturate its innards for hours and even days after their initial appearance. In the seas and oceans, the lingering presence of electromagnetic fields photonically imparted by sunlight, triggers the electrolysis responsible for most of the Earth’s hydrogen. An essential form of photosynthesis, solar water splitting is the cleanest and most efficient means imaginable for generating and storing energy. —Evelina Domnitch & Dmitry Gelfand *** Animals and plants are formed in earth and in water because there is water in earth, and there is pneuma in water, and there is soul heat in all pneuma ; so that in a way all things are full of soul. Hence plants and animals quickly form once this gets enclosed; and when this enclosing happens, when the corporeal liquids get heated, a sort of frothy bubble is formed. Now the difference between the various creatures which are produced in this way are due to the stuff which makes up the envelope around the soul-source.2 Throwing light into this pneumatic spray of perdurances, which would otherwise swarm below the threshold of human visibility, Evelina Domnitch and Dmitry Gelfand’s Hydrogeny saturates the viewer’s sensorial space with the nano-architectures of froth. Straddling the cell wall between scientific enquiry and artistic praxis, Hydrogeny , beckons a recasting of Lucretius' clinamen in tune with the technologies of the modern observer. For Lucretius it was the indeterminate swerving of an atomistic layer of reality which accounted for the unpredictability of change and the existence of free will. Taken up by Harold Bloom to describe the swerving of cultural production from that which has already been made, the idea has since been textually redressed by Lacan, Derrida, Serres, Deleuze, Nancy, and Badiou. Here we have been given a kaleidoscopic technique for refining and expanding awareness of our enmeshment with so many nested, atomistic layers of object-bubbles—of things—as Aristotle might say,“full of soul.” The gravitational pull of Hydrogeny ushers a de-centered human spectatorship to the ever more intimate recesses of what media philosopher N. Katherine Hayles calls our capacity for “deep attention.”3 Vaporous attention suspended and re-oriented. Microscopic as these diaphanous waves are, the calling they produce is anything but inconsequential. Evelina Domnitch and Dmitry Gelfand are two-thirds of the Amsterdam-based Art–Science Labratory, Optofonica , an atelier initiated by the Italian interdisciplinary artist TeZ in 2006. Follow more of their work at www.portablepalace.com —Isaac Linder NOTES (1) cf. Brandon, Kelsall, Levine, & Smith. “Interfacial Electrical Properties of Electrogenerated Bubbles.” Journal of Applied Electrochemistry 15 (1985):485-493. (2)Aristotle, On the Generation of Animals, 762a18, tr. A. L. Peck (Cambridge, MA: Loeb Classical Library, 1942). (3)“ My article on hyper and deep attention ,” N. Katherine Hayles, accessed on September 14, 2011. (shrink)

No overarching hypotheses tie the basic mechanisms of mitochondrial reactive oxygen species (ROS) production to activity dependent synapse pruning—a fundamental biological process in health and disease. Neuronal activity divergently regulates mitochondrial ROS: activity decreases whereas inactivity increases their production, respectively. Placing mitochondrial ROS as innate synaptic activity sentinels informs the novel hypothesis that: (1) at an inactive synapse, increased mitochondrial ROS production initiates intrinsic apoptosis dependent pruning; and (2) at an active synapse, decreased mitochondrial ROS production (...) masks intrinsic apoptosis dependent pruning. Immature antioxidant defense may enable the developing brain to harness mitochondrial ROS to prune weak synapses. Beyond development, endogenous antioxidant defense constrains mitochondrial (ROS) to mask pruning. Unwanted age‐related synapse loss may arise when mitochondrial ROS aberrantly recapitulate developmental pruning. Placing mitochondrial ROS with their hands on the shears is beneficial in early but deleterious in later life. (shrink)

The interaction between science and technology in the Industrial Revolution has been debated by various authors over the years. Most recently, Ursula Klein has described eighteenth-century chemistry as an interconnected system of science and technology because of the inherently productive nature of chemical experimentation. The technology used in the nineteenth gaslight industry follows the pattern that Klein describes: gaslight technology was derived from the academic studies of eighteenth-century pneumatic chemists. The foundation of the technology in science included first, a knowledge (...) about inflammable gases and their properties, and second, various instruments and processes developed for the study of gases. Although inflammable exhalations had been known long before the eighteenth-century, it was only with the work of Priestley, Volta, Berthollet, and other chemists that their properties and characteristics, including the multiplicity of species of inflammable gases, became known. The instruments and processes of pneumatic chemistry that were incorporated into gaslight apparatus were the retort, the pneumatic trough, lime purification of carbon dioxide and hydrogen sulphide, and finally the gasometer. The first important instance of lighting with inflammable gases, that of J. P. Minckelers in 1785, demonstrates that pneumatic chemistry formed part of an interconnected network of science and technology, as does the work of other early gaslight pioneers such as Philippe Lebon, Zachäus Winzler, and William Murdoch. Lebon came to gaslight through the investigation of distillation processes, and later thought of using the inflammable gas produced in this way. Zachäus Winzler, an Austrian chemist, recreated Lebon's thermolamp from the instruments in his laboratory after hearing descriptions of it. In the case of William Murdoch, he incorporated the pneumatic apparatus that James Watt had built for Thomas Beddoes. (shrink)

The Earth agglomerates and heats. Convection cells within the planetary interior expedite the cooling process. Volcanoes evolve steam, carbon dioxide, sulfur dioxide and pyrophosphate. An acidulous Hadean ocean condenses from the carbon dioxide atmosphere. Dusts and stratospheric sulfurous smogs absorb a proportion of the Sun’s rays. The cooled ocean leaks into the stressed crust and also convects. High temperature acid springs, coupled to magmatic plumes and spreading centers, emit iron, manganese, zinc, cobalt and nickel ions to the ocean. Away from (...) the spreading centers cooler alkaline spring waters emanate from the ocean floor. These bear hydrogen, formate, ammonia, hydrosulfide and minor methane thiol. The thermal potential begins to be dissipated but the chemical potential is dammed. The exhaling alkaline solutions are frustrated in their further attempt to mix thoroughly with their oceanic source by the spontaneous precipitation of biomorphic barriers of colloidal iron compounds and other minerals. It is here we surmise that organic molecules are synthesized, filtered, concentrated and adsorbed, while acetate and methane—separate products of the precursor to the reductive acetyl-coenzyme-A pathway—are exhaled as waste. Reactions in mineral compartments produce acetate, amino acids, and the components of nucleosides. Short peptides, condensed from the simple amino acids, sequester ‘ready-made’ iron sulfide clusters to form protoferredoxins, and also bind phosphates. Nucleotides are assembled from amino acids, simple phosphates carbon dioxide and ribose phosphate upon nanocrystalline mineral surfaces. The side chains of particular amino acids register to fitting nucleotide triplet clefts. Keyed in, the amino acids are polymerized, through acid–base catalysis, to alpha chains. Peptides, the tenuous outer-most filaments of the nanocrysts, continually peel away from bound RNA. The polymers are concentrated at cooler regions of the mineral compartments through thermophoresis. RNA is reproduced through a convective polymerase chain reaction operating between 40 and 100°C. The coded peptides produce true ferredoxins, the ubiquitous proteins with the longest evolutionary pedigree. They take over the role of catalyst and electron transfer agent from the iron sulfides. Other iron–nickel sulfide clusters, sequestered now by cysteine residues as CO-dehydrogenase and acetyl-coenzyme-A synthase, promote further chemosynthesis and support the hatchery—the electrochemical reactor—from which they sprang. Reactions and interactions fall into step as further pathways are negotiated. This hydrothermal circuitry offers a continuous supply of material and chemical energy, as well as electricity and proticity at a potential appropriate for the onset of life in the dark, a rapidly emerging kinetic structure born to persist, evolve and generate entropy while the sun shines. (shrink)

1. Introduction : humanity's urge to understand -- 2. Elements of scientific thinking : skepticism, careful reasoning, and exhaustive evaluation are all vital. Science Is universal -- Maintaining a critical attitude. Reasonable skepticism -- Respect for the truth -- Reasoning. Deduction -- Induction -- Paradigm shifts -- Evaluating scientific hypotheses. Ockham's razor -- Quantitative evaluation -- Verification by others -- Statistics : correlation and causation -- Statistics : the indeterminacy of the small -- Careful definition -- Science at the frontier. (...) When good theories become ugly -- Stuff that just does not fit -- 3. Christopher Columbus and the discovery of the "Indies" : it can be disastrous to stubbornly refuse to recognize that you have falsified your own hypothesis -- 4. Antoine Lavoisier and Joseph Priestley both test the befuddling phlogiston theory : junking a confusing hypothesis may be necessary to clear the way for new and productive science -- 5. Michael Faraday discovers electromagnetic induction but fails to unify electromagnetism and gravitation : it is usually productive to simplify and consolidate your hypotheses -- 6. Wilhelm Röntgen intended to study cathode rays but ended up discovering X-rays : listen carefully when Mother Nature whispers in your ear : she may be leading you to a Nobel Prize -- 7. Max Planck, the first superhero of quantum theory, saves the universe from the ultraviolet catastrophe : assemble two flawed hypotheses about a key phenomenon into a model that fits experiment exactly and people will listen to you even if you must revolutionize physics -- 8. Albert Einstein attacks the problem "Are atoms real?" from every angle : solving a centuries-old riddle in seven different ways can finally resolve it -- 9. Niels Bohr models the hydrogen atom as a quantized system with compelling exactness, but his later career proves that collaboration and developing new talent can become more significant than the groundbreaking research of any individual -- 10. Conclusions, status of science, and lessons for our time. Conclusions from our biographies -- What thought processes lead to innovation? -- Is the scientist an outsider? -- The status of the modern scientific enterprise -- Lessons for our time -- Can the scientific method be applied to public policy? -- Why so little interest in science? -- Knowledge is never complete. (shrink)

We examine “de Broglie-Bohm” causal trajectories for the two electrons in a nonrelativistic helium atom, taking into account the spin-dependent momentum terms that arise from the Pauli current. Given that this many-body problem is not exactly solvable, we examine approximations to various helium eigenstates provided by a low-dimensional basis comprised of tensor products of one-particle hydrogenic eigenstates.First to be considered are the simplest approximations to the ground and first-excited electronic states found in every introductory quantum mechanics textbook. For example, the (...) trajectories associated with the simple 1s(1)1s(2) approximation to the ground state are, to say the least, nontrivial and nonclassical.We then examine higher-dimensional approximations, i.e., eigenstates Ψ α of the Hamiltonian in this truncated basis, and show that ∇ i S α =0 for both particles, implying that only the spin-dependent momentum term contributes to electronic motion. This result is independent of the size of the truncated basis set, implying that the qualitative features of the trajectories will be the same, regardless of the accuracy of the eigenfunction approximation.The electronic motion associated with these eigenstates is quite specialized due to the condition that the spins of the two electrons comprise a two-spin eigenfunction of the total spin operator. The electrons either (i) remain stationary or (ii) execute circular orbits around the z-axis with constant velocity. (shrink)

Reactive oxygen species (ROS) are known as toxic metabolic products in plants and other aerobic organisms. An elaborate and highly redundant plant ROS network, composed of antioxidant enzymes, antioxidants and ROS-producing enzymes, is responsible for maintaining ROS levels under tight control. This allows ROS to serve as signaling molecules that coordinate an astonishing range of diverse plant processes. The specificity of the biological response to ROS depends on the chemical identity of ROS, intensity of the signal, sites of production, (...) plant developmental stage, previous stresses encountered and interactions with other signaling molecules such as nitric oxide, lipid messengers and plant hormones. Although many components of the ROS signaling network have recently been identified, the challenge remains to understand how ROS-derived signals are integrated to eventually regulate such biological processes as plant growth, development, stress adaptation and programmed cell death. (shrink)

Although the generation of reactive oxygen species is an activity normally associated with phagocytic leucocytes, mammalian spermatozoa were, in fact, the first cell type in which this activity was described. In recent years it has become apparent that spermatozoa are not the only nonphagocytic cells to exhibit a capacity for reactive oxygen species production, because this activity has been detected in a wide variety of different cells including fibroblasts, mesangial cells, oocytes, Leyding cells endothelial cells, thryroid cells, adipocytes, tumour (...) cell and platelets. Since the capacity to generate reactive oxygen species is apparently so widespread, the risk‐benefit equation for these potentially pernicious molecules becomes a matter of intese interest. In the case of human spermatozoa, the risk of manufacturing reactive oxygen metabolites is considerable because these cells are particularly vulnerable to lipid peroxidation. Indeed, there is now good evidence to indicate that oxygen radicals are involved in the initiation of peroxidative damage to the sperm plasma membrane, seen in many cases of male infertility. This risk is off‐set by recent data suggesting that superoxide anions and hydrogen peroxide also participate in the induction of key biological events such as hyperactiavated motility and the acrosome reaction. Thus, human spermatozoa appear to use reactive oxygen species for a physiological purpose and have the difficult task of ensuring the balanced generation of these potentially harmful, but biologically important, modulators of cellular function. (shrink)

Introduction of O2 to Earth's early biosphere stimulated remarkable evolutionary adaptations, and a wide range of electron acceptors allowed diverse, energy-yielding metabolic pathways. Enzymatic reduction of O2 yielded a several-fold increase in energy production, enabling evolution of multi-cellular animal life. However, utilization of O2 also presented major challenges as O2 and many of its derived reactive oxygen species are highly toxic, possibly impeding multicellular evolution after the Great Oxidation Event. Remarkably, ROS, and especially hydrogen peroxide, seem to play (...) a major part in early diversification and further development of cellular respiration and other oxygenic pathways, thus becoming an intricate part of evolution of complex life. Hence, although harnessing of chemical and thermo-dynamic properties of O2 for aerobic metabolism is generally considered to be an evolutionary milestone, the ability to use ROS for cell signaling and regulation may have been the first true breakthrough in development of complex life. The importance of Earth's oxygen cycle and reactive oxygen species produced on the evolution of complex life. The ability to detoxify oxygen species is not a trait that emerged as a response to increased O2 levels but rather crucial adaptation to the early Earth's weakly oxic microenvironments. (shrink)

Prout's hypothesis was influential in—if not necessary for—the establishment of the atomic weight of oxygen, a figure conclusively demonstrated in 1895. Ironically, the successful determination of oxygen's weight also led to a final refutation of the hypothesis . But more than this, the end of Prout's hypothesis via the determination of oxygen's atomic weight was due to three fundamental changes that characterized the way chemistry was practised and communicated in the late nineteenth century. First, encyclopaedia‐like presentations of past atomic‐weight investigations (...) became the focus in numerous and influential studies. Second, there was a dramatic change in the way professional publications presented investigations and experiments, characterized by experimental detail and apparatus design at the expense of theoretical discussion. Finally, the production of hydrogen became the focus of research, as it was one of the principal components of any investigation into atomic weights. Here I present Prout's hypothesis in its historical context by focusing on these three developments and their influence on the research of Edward Williams Morley. While doing so I also illustrate the way marginalized scientists were able to take advantage of their otherwise dubious position and participate in an active and important role in atomic‐weight investigations. (shrink)

Abstract Environmental and public health-focused sciences are increasingly characterised as constituting an emerging discipline—planetary medicine. From a governance perspective, the ethical components of that discipline may usefully be viewed as bestowing upon our ailing natural environment the symbolic moral status of a patient. Such components emphasise, for example, the origins and content of professional and social virtues and related ethical principles needed to promote global governance systems and policies that reduce ecological stresses and pathologies derived from human overpopulation, selfishness and (...) greed—such as pollution, loss of biodiversity, deforestation and greenhouse gas emissions, as well as provide necessary energy, water and food security. Less well explored in this context, however, is the ethics that should underpin global use of emerging technologies such as nanotechnology as forms of planetary therapeutics. Nanotechnology may be particularly important, for instance, as a mechanism for improving upon photosynthesis and engineering it into human structures for localised production of carbon-neutral hydrogen based-fuel and carbohydrate-based food and fertilizer. Artificial photosynthesis, because of its unique and widespread public and environmental benefits in this period of human history, may even be termed the moral culmination of nanotechnology, assisting this planet to move beyond the Anthropocene epoch to that of the Sustainocene. This paper explores practical steps towards planetary nanomedicine involving governance of artificial photosynthesis, including a UNESCO Universal Declaration on the Bioethics and Human Rights of Natural and Artificial Photosynthesis (Global Solar Fuels and Foods ). Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s11569-012-0144-4 Authors Thomas Faunce, College of Medicine, Biology and the Environment and College of Law (joint Appointment), Australian National University, Acton, Australia Journal NanoEthics Online ISSN 1871-4765 Print ISSN 1871-4757. (shrink)

Hydrogen is troublesome in any periodic table classification. This being so it may as well be placed in a position that confers desirable attributes to the arrangement of the elements, while notionally recognising its lineage to the group 1 alkali metals and the group 17 halogens. Since the noble gases bridge the halogens and the alkali metals, and hydrogen encompasses the transition from the alkali metals to the halogens, there is more to the idea of hydrogen over (...) helium. (Meyer 1870, p. 357) (Proust 1927, p. 559). (shrink)

The history of the hydrogen bond provides a good example of the of an important chemical concept. It illustrates the interplay between empirical and theoretical approaches to the problem of delimiting what has proved to be quite an elusive notion, with chemists whittling away at the particular sorts of case with a view to obtaining a precise, unitary concept. Even though there is a return to a more theoretically inspired notion in more recent research, empirical characterisations remain a feature (...) of the report of a Task Group recently set up by the IUPAC to reconsider the definition of the hydrogen bond, and this situation—by no means unusual for chemical concepts and principles—is unlikely to change in the foreseeable future. These developments are reviewed in this paper, which includes an extended discussion of the enormous significance hydrogen bonding has for the philosopher’s standard example of a “natural kind”, water. There is little to suggest a reduction to what philosophers of physics are pleased to call fundamental principles, and the details raise further questions about what essentialists could possibly have in mind when talking about the microscopic essence of water. (shrink)

The hydrogen economy is a technological bluff in its implied assurance that, despite the accelerating pace at which we are depleting the remaining half of our fossil fuels, our energy future is secure. Elementary thermodynamic considerations are developed to show that a hydrogen economy is about as feasible as a perpetual motion machine. Hydrogen is not an energy source but an energy carrier, and when produced renewably, it is an energy carrier to the second degree, with electricity (...) being the energy carrier to the first degree. As such, it greatly elongates the chain of energy transformations required to deliver a desired service from a primary source of energy. There will undoubtedly be applications in which hydrogen may be essential, but they will be limited because the services it delivers will come at a substantial energy premium. (shrink)