Megaton Scale Research Articles

NuTag: a proof-of-concept study for a long-baseline neutrino beam

The study of neutrino oscillation at accelerators is limited by systematic uncertainties, in particular on the neutrino flux, cross section, and energy estimates. These systematic uncertainties could be eliminated by a novel experimental technique: neutrino tagging. This technique relies on a new type of neutrino beamline and its associated instrumentation which would enable the kinematic reconstruction of the neutrinos produced in and decays. This article presents a proof-of-concept study for such a tagged beamline, aiming to serve a long-baseline neutrino experiment exploiting a megaton scale natural water Cherenkov detector. After optimising the target and the beamline optics to first order, a complete Monte Carlo simulation of the beamline has been performed. The results show that the beamline provides a meson beam compatible with the operation of the spectrometer, and delivers a neutrino flux sufficient to collect neutrino samples with a size comparable with similar experiments and with other un-tagged long-baseline neutrino experimental proposals.

Highly productive V/Zn-SiO2 catalysts for the selective oxidation of methane

The production of formaldehyde on industrial scale requires huge amounts of energy due to the involvement of reforming processes in combination with the demand in the megaton scale. Hence, a direct route for the transformation of (bio)methane to formaldehyde would decrease costs and puts less pressure on the environment. Herein, we report on the use of zinc modified silicas as possible support materials for vanadium catalysts and the resulting consequences for the performance in the selective oxidation of methane to formaldehyde. After optimization of the Zn content and reaction conditions, a remarkably high space-time yield of 12.4 kgCH2O·kgcat−1·h−1 was achieved. As a result of the extensive characterization by means of UV–vis, Raman, XANES and NMR spectroscopy it was found that vanadium is in the vicinity of highly dispersed zinc atoms which promote the formation of active vanadium species as supposed by theoretical calculations. This work presents a further step of catalyst development towards direct industrial methane conversion which may help to overcome current limitations in the future.

Bark extractives as sources of carbon-efficient functional precursors and materials

<p>Biomass residues generated in forest operations represent an abundant and renewable resource in need for valorization. Bark is becoming increasingly relevant, not only in the bioproducts sector, but also in the context of the circular bioeconomy, which is placing emphasis on underutilized residues and waste. Among these, tree bark is one of the largest forestry by-products, accessible at a megaton scale but so far mostly utilized for its solid fuel value. Bark valorization should include the isolation of valuable natural compounds that add functionalities to a variety of bioproducts. This is the subject of this review, which considers bark extractives prospects, under the biorefinery concept, placing attention on extractives' chemical profiles and properties. We introduce the most recent pathways reported for bark fractionation and the opportunities to achieve new materials by using the concepts of supramolecular chemistry, leading to special assemblies. We show that value-added chemicals and materials are possible and expected to become most relevant in efforts aimed at maximizing bark utilization.</p>

Neutrino tagging: a new tool for accelerator based neutrino experiments

This article describes a new experimental method for accelerator based neutrino experiments called neutrino tagging. The method consists in exploiting the neutrino production mechanism, the decay, to kinematically reconstruct the neutrino properties from the decay incoming and outgoing charged particles. The reconstruction of these particles relies on the recent progress and on-going developments in silicon particle detector technology. A detailed description of the method and achievable key performances is presented, together with its potential benefits for short and long baseline experiments. Then, a novel configuration for long baseline experiments is discussed in which a tagged beam would be employed together with mega-ton scale natural deep water Cherenkov detectors. The coarseness of this type of detectors is overcome by the precision of the tagging and, conversely, the rate limitation imposed by the tagging is outweighed by the size of the detector. These mutual benefits result in an affordable design for next generations of long baseline experiments. The physics potential of such experiments is quantified using the Protvino to KM3NeT/ORCA setup as a case study for which an unprecedented sensitivity to the leptonic CP violation could be achieved.

Ядерная индустриализация Луны

The industrialization of the Moon is a process that, when copying earthly technologies, will stretch for centuries. At the same time, progressive technologies are known that are inapplicable in terrestrial conditions, but can be successfully implemented on the moon, which will lead to the rapid creation of an industry that produces inexpensive rocket fuel on a megaton scale. This is an industry based on new physical principles. The introduction of such technologies is hindered by a political factor – two international agreements on the prohibition of nuclear explosions. At the same time, the agreements contain legal incidents allowing the use of nuclear explosions outside the Earth, as well as possible technical innovations that take nuclear technologies with pulsed energy release out of the existing political restrictions.

Co‐Ni‐P‐B catalyzed hydroformylation of long linear α olefins

AbstractBACKGROUNDAs indirect liquefaction of coal has been carried out in megaton scale, extension of the Fischer‐Tropsch synthesis products has received renewed interest. Hydroformylation provides a way for the transformation of alkenes to aldehydes. Homogeneous rhodium complex catalysts are efficacious but expensive and not easy to recover and reuse. Heterogeneous catalysts are desired to enable their easy separation. Amorphous four‐component non‐precious metal catalysts were prepared using facile reduction and their activity toward hydroformylation of long linear α olefins was investigated.RESULTSObtained Co‐Ni‐P‐B presented uniform nanoparticles that were well‐dispersed Co with more electrons, attributing to isolation and electron transfer among the four components. The Co, Ni, P, and B were in both atomic states and oxidation states. The Co in Co‐Ni‐P‐B was shown to be electron‐enriched with enhanced catalytic activity. Co‐Ni‐P‐B displayed good catalytic activity for hydroformylation of linear C6, C8, C10, or C12 α olefins, and the highest activity for 1‐octene. The conversion of 1‐octene and the selectivity of C9 aldehydes reached 99.62% and 96.30%, respectively. The ratio of nonanal to isononanal was 1.44. The selectivity for isomeric products was 3.70%. There existed an appropriate four‐component ratio for hydroformylation of 1‐octene owing to synergistic effects among the Co, Ni, P, and B. Co‐Ni‐P‐B exhibited good reusability.CONCLUSIONAmorphous four‐component Co‐Ni‐P‐B prepared by facile reduction showed good catalytic performance toward hydroformylation of long linear C6, C8, C10, or C12 α olefins due to synergistic effects among the Co, Ni, P, and B. © 2021 Society of Chemical Industry (SCI).

Zeolite (In)Stability under Aqueous or Steaming Conditions.

Zeolites are among the most environmentally friendly materials produced industrially at the Megaton scale. They find numerous commercial applications, particularly in catalysis, adsorption, and separation. Under ambient conditions aluminosilicate zeolites are stable when exposed to water or water vapor. However, at extreme conditions as high temperature, high water vapor pressure or increased acidity/basicity, their crystalline framework can be destroyed. The stability of the zeolite framework under aqueous conditions also depends on the concentration and character of heteroatoms (other than Al) and the topology of the zeolite. The factors critical for zeolite (in)stability in the presence of water under various conditions are reviewed from the experimental as well as computational sides. Nonreactive and reactive interactions of water with zeolites are addressed. The goal of this review is to provide a comparative overview of all-silica zeolites, aluminosilicates and zeolites with other heteroatoms (Ti, Sn, and Ge) when contacted with water. Due attention is also devoted to the situation when partial zeolite hydrolysis is used beneficially, such as the formation of hierarchical zeolites, synthesis of new zeolites or fine-tuning catalytic or adsorption characteristics of zeolites.

Current and Future Trends in Polyurethanes: An Industrial Perspective

AbstractThe urethane polyaddition reaction was discovered about 80 years ago. Since then this chemistry has further developed into many industrial applications and grown into a multibillion dollar business. The versatility of polyurethanes is founded in a broad spectrum of properties which can be achieved ranging from flexible to rigid and from compact to foamed by choosing suitable combinations of starting materials, the key raw materials being polyol and isocyanate. While on the industrial megaton scale the number of isocyanate building blocks is quite limited, there is a huge choice of polyols and additives available to achieve tailor‐made polymer properties for various applications. For the future development of polyurethanes, the two major trends, i) the further improvement of all sustainability characteristics and ii) digitalization in product and process development, are discussed. The former is reflected in four main areas: the production of improved insulation materials to reduce energy consumption; production of raw materials with an improved carbon footprint; odor and emission reduction in indoor applications; and recycling of production and consumer waste. The present review concludes with a few examples as to how digitalization can change and accelerate research and development work in the future.

Implementation of voluntary verification of sustainability for solid biomass\u2014a case study from Denmark

BackgroundRenewable energy and biomass are becoming increasingly important energy sources to help mitigate climate change and meet national renewable energy targets. This will lead to a substantial growth in solid biomass consumption for heat and electricity, but questions about its sustainability have been raised. Danish energy companies have addressed these issues with sustainability criteria in a voluntary industry agreement since 2016. The aim of this study was to synthesise and evaluate biomass sourcing in the Danish energy sector and its compliance with voluntary sustainability criteria.MethodsWe collected energy companies’ public industry agreement sustainability reports and compiled the included information into a dataset that allowed us to compare and analyse the Danish energy sector’s biomass sourcing, compliance and implementation of sustainability criteria in 2016 and 2017. Furthermore, we analysed the supply chains and feedstock use of Danish energy companies.ResultsIn Denmark, medium to large energy companies documented that 57% and 70% of their biomass sourcing was in compliance with the sustainability criteria in 2016 and 2017, respectively. To show compliance with the sustainability criteria, sustainable forest management certification was most common in 2016 while risk-based certification prevailed in 2017. Most biomass is sourced and reported sustainability compliance by a few large companies. Wood pellets are sustainability reported and sourced in significantly larger volumes than wood chips. Danish energy companies source solid biomass from local to global scales, but especially from countries around the Baltic Sea.ConclusionsThe Danish approach to sustainable sourcing with voluntary sustainability criteria has been successfully implemented for most of the wood sourced for energy by medium to large energy companies in Denmark. The implementation of this approach shows that it has been possible within a couple of years to implement sustainability governance with risk-based criteria for multiple energy companies that source solid wood biomass at the megaton scale. A risk-based approach to implementation of sustainability criteria for forest biomass has also been chosen by the European Union (EU) and will be implemented through the EU Renewable Energy Directive from 2021.

The European Spallation Source neutrino Super Beam Design Study

The discovery of oscillations and the latest progress in neutrino physics will make possible to observe, for the first time, CP violation in the lepton sector, if it exists. This will help to understand the disappearance of antimatter in the Universe. To go further beyond the current knowledge, it is necessary to develop more and more powerful instruments, but also to combine skills by creating strong international networks between researchers. In this framework, the ESSvSB project proposes to use the proton linac of the European Spallation Source (ESS) currently in construction in Lund (Sweden) to produce a very intense neutrino Super Beam, in parallel with the spallation neutron production. The ESS linac is expected to be fully operational by 2023 delivering 5 MW average power, 2 GeV proton beam, with 2.86 ms long pulses at a rate of 14 Hz. By doubling the pulse rate, an average power of 10 MW can be obtained, providing at the same time 5 MW for the neutron facility and the 5 MW for the production of the neutrino beam. The primary proton beam-line completing the linac will consist of an accumulator ring to compress the beam pulses to 1.3 μs and a switchyard to distribute the protons onto the target station. The secondary beam-line producing neutrinos will consist of a four-horn/target station, a decay tunnel and a beam dump. A megaton scale Water Cherenkov neutrino detector will be located at a baseline of about 500 km in one of the existing mines in Sweden, to measure the neutrino oscillations.

SWRO-PRO System in “Mega-ton Water System” for Energy Reduction and Low Environmental Impact

Reverse osmosis (RO) membranes have been widely applied in seawater desalination (SWRO) and wastewater reclamation as the main desalination technology since 2000. SWRO plants face challenges to reduce energy consumption and brine disposal to lessen marine pollution. To tackle these challenges, a SWRO-PRO (Pressure Retarded Osmosis) System was proposed in the “Mega-ton Water System” project under the Japanese national project of the “Funding Program for World-Leading Innovative R&D on Science and Technology” (FIRST Program). To reduce the energy consumption of the main SWRO plant, an innovative low-pressure SWRO membrane and a next generation energy recovery device (ERD) were developed by the “Mega-ton Water System” project. In addition to this research and development, a new membrane process has been proposed and confirmed as a low-pressure multi-stage SWRO (LMS). A brine conversion two-stage SWRO system was invented 20 years ago, and has been in operation for over 15 years. Application of the SWRO membrane process to actual commercial plants was an important research theme. The low-pressure multi-stage SWRO System (LMS) was an innovative method of introducing a low-pressure membrane and the membrane element in the pressure vessel was designed to avoid heavy fouling of lead elements. As a result of these developments at mega-ton scale SWRO plants, a 20% energy reduction was possible in the SWRO system of the “Mega-ton Water System”. In the development of the PRO process, a PRO hollow fiber membrane module with a maximum 13.3 w/m2 of membrane power density using a 10-inch module was established at a prototype PRO plant. Thus, a 30% energy reduction was possible using the SWRO-PRO System in the “Mega-ton Water System” at mega-ton scale SWRO plants. The brine disposal problem was also solved by this system.

KM3NeT-ORCA: Oscillation Research with Cosmics in the Abyss

KM3NeT, currently under construction in the abysses of the Mediterranean Sea, is a distributed research infrastructure that will host a km3-scale neutrino telescope (ARCA) for high-energy neutrino astronomy, and a megaton scale detector (ORCA) for neutrino oscillation studies of atmospheric neutrinos. ORCA is optimised for a measurement of the mass hierarchy, providing a sensitivity of 3σ after 3-4 years. It will also measure the atmospheric mixing parameters Δm2atm and θ23 with a precision comparable to the NOvA and T2K experiments using both the muon neutrino disappearance and tau neutrino appearance channels. It will provide a measurement of the tau neutrino appearance rate with better than 10% precision, a crucial ingredient for tests of unitarity. It will probe the octant of the mixing angle θ23 via matter resonance effects on neutrinos and antineutrinos crossing the core and mantle, which are largely independent on the CP phase. The observation of neutrino oscillations over a wide range of baselines and energies will provide broad sensitivity to new physics such as non-standard neutrino interactions (NSI) and sterile neutrinos.

Role of pressure-retarded osmosis (PRO) in the mega-ton water project

AbstractReverse osmosis (RO) membranes have been widely applied to seawater desalination and wastewater reclamation, and many large RO plants (>100,000 m3/d) have been constructed since 2000. Energy efficiency is indispensable for large plants, especially for future mega-ton scale seawater reverse osmosis (SWRO) plant (1,000,000 m3/d). In order to reduce energy demand in RO operation, high-efficient low-pressure RO membrane, energy recovery device (ERD), and pressure-retarded osmosis (PRO) which would recover power from salinity gradient between freshwater and concentrated brine were studied in the “Mega-ton Water System” project. A PRO hollow fiber membrane module was newly developed, and a practical continuous operation has been examined at a prototype plant for one year. The maximum 13.5 W/m2 of membrane power density using 10-inch module was established at our prototype PRO plant. As the results of the plant cost estimation and the financial impacts on the energy saving operation at the mega-ton scale...

Energy recovery by PRO in sea water desalination plant

Sea water reverse osmosis (SWRO) would face some problems like energy saving and management of concentrated brine. To solve these problems at the same time, the energy recovery by Pressure Retarded Osmosis (PRO) was proposed in the Mega-ton Water System project. Prototype plant test was conducted using concentrated brine from SWRO plant and fresh water from regional waste water treatment facility. Hollow-fiber membrane module were examined in the prototype plant and the test operation was carried out for more than one year. We have reached the maximum membrane power density, 13.5W/m2, using 10-in. module. Followings were still existing obstacles for further effective PRO. It was also challenging how to get clean fresh water from waste or river water without additional cost. Innovative new technologies were also required to address these concerns. We have also estimated plant cost and surveyed financial impacts on the energy saving of SWRO operation, based on the situation of currently operated SWRO plants worldwide, especially about the Mega-ton scale ones. Those studies indicated that potential market of PRO was 1–2GW, and 10% energy saving was possible on the Megaton scale SWRO plants. Those results indicate that the commercialization plant would be available very near future.

Future Long-Baseline Neutrino Facilities and Detectors

We review the ongoing effort in the US, Japan, and Europe of the scientific community to study the location and the detector performance of the next-generation long-baseline neutrino facility. For many decades, research on the properties of neutrinos and the use of neutrinos to study the fundamental building blocks of matter has unveiled new, unexpected laws of nature. Results of neutrino experiments have triggered a tremendous amount of development in theory: theories beyond the standard model or at least extensions of it and development of the standard solar model and modeling of supernova explosions as well as the development of theories to explain the matter-antimatter asymmetry in the universe. Neutrino physics is one of the most dynamic and exciting fields of research in fundamental particle physics and astrophysics. The next-generation neutrino detector will address two aspects: fundamental properties of the neutrino like mass hierarchy, mixing angles, and the CP phase, and low-energy neutrino astronomy with solar, atmospheric, and supernova neutrinos. Such a new detector naturally allows for major improvements in the search for nucleon decay. A next-generation neutrino observatory needs a huge, megaton scale detector which in turn has to be installed in a new, international underground laboratory, capable of hosting such a huge detector.

MEMPHYS: A next generation megaton scale water Cherenkov detector in Europe

Future large underground detectors for neutrino physics are studied in Europe within the FP7 design studies LAGUNA, EUROnu and Laguna-LBNO. In this paper the MEMPHYS detector and its development phases are described. MEMPHYS is a proposed 0.5 Mton scale Water Cherenkov experiment to be performed deep underground. It is dedicated to nucleon decay, neutrinos from supernovse, solar and atmospheric neutrinos, as well as neutrinos from a future Super-Beam (SB) or β-Beam (βB) to measure the mixing angle θ13, the CP violating phase δ and the mass hierarchy. A small-scale prototype, MEMPHYNO, has been constructed with the purpose of serving as a test bench for new photo detection and data acquisition solutions.

LAGUNA-LBNO: Large Apparatus studying Grand Unification and Neutrino Astrophysics and Long Baseline Neutrino Oscillations

LAGUNA (Large Apparatus studying Grand Unification and Neutrino Astrophysics) and LAGUNA-LBNO (Large Apparatus studying Grand Unification and Neutrino Astrophysics and Long Baseline Neutrino Oscillations) are European FP7 Design Studies. Within these studies Pan-European research infrastructures in deep underground cavities able to host a very large multipurpose next-generation neutrino observatory are investigated. These future megaton scale detectors are dedicated to nucleon decay, neutrinos from supernovse, solar and atmospheric neutrinos, as well as neutrinos from a future Super-Beam or β-Beam to measure the mixing angle θ13, the CP violating phase δ and the mass hierarchy.

LAGUNA and LAGUNA–LBNO: Future megaton neutrino detectors in Europe

The FP7 Design Studies LAGUNA (Large Apparatus studying Grand Unification and Neutrino Astrophysics) and LAGUNA–LBNO (Large Apparatus studying Grand Unification and Neutrino Astrophysics and Long Baseline Neutrino Oscillations) are studying Pan-European research infrastructures in deep underground cavities able to host a very large multipurpose next-generation neutrino observatory. These future megaton scale detectors are dedicated to nucleon decay, neutrinos from supernovæ, solar and atmospheric neutrinos, as well as neutrinos from a future Super-Beam or β-Beam to measure the mixing angle θ13, the CP violating phase δ and the mass hierarchy.

Neutrino Experiments: Perspectives

There is a standard and ‘common’ scenario for the future of the neutrino experiments. The predicted region by the inverted mass hierarchy for the double beta decay may be reached in a few years and the CPV effects may be examined by a Megaton scale detector and a few MW of super-beams. But here we discuss one step beyond the standard scenario and consider how we can achieve such goals. We also investigate a possible modification of an existing detector for future experiments.

Synthesis of Multiwalled Carbon Nanotubes on Fly Ash Derived Catalysts

Carbon nanotubes (CNTs) are an allotrope of carbon with unique properties that make them potentially useful in a vast range of applications. However, CNTs are predominantly produced using expensive and/or nonrecyclable catalyst supports, e.g., mesoporous silica and alumina. In this work, coal combustion fly ash, a bulk waste product with limited uses, was impregnated with iron nitrate and successfully used as a substrate to produce industrial grade multiwalled carbon nanotubes (MWNTs) by fluidized bed chemical vapor deposition. CNTs were analyzed using thermogravimetric analysis, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. The most successful catalyst trialed at 650 degrees C using ethylene as a carbon source was a 5 wt % Fe fly ash catalyst, which produced a CNT yield in respect to metal loading of approximately 82.5%. The MWNTs had outer diameters of between 12 and 20 nm with a reasonable degree of wall graphitization (I(G)/I(D) of 1.17). Advantages of utilizing fly ash as a catalyst support are its availability at low cost at the megaton scale, its high thermal stability, and suitability for use in industrial fluidized bed reactors. Potential applications for the fly ash produced CNTs include use in composite materials.