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This study aims to propose a semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the high-speed railway (HSR) subgrade under cyclic load.

According to the basic framework of critical state soil mechanics and in view of the characteristics of the coarse-grained soil filler for the HSR subgrade to bear the train vibration load repeatedly for a long time, the hyperbolic empirical relationship between particle breakage and plastic work was derived. Considering the influence of cyclic vibration time and stress ratio, the particle breakage correction function of coarse-grained soil filler for the HSR subgrade under cyclic load was proposed. According to the classical theory of plastic mechanics, the shearing dilatation equation of the coarse-grained soil filler for the HSR subgrade considering particle breakage was modified and obtained. A semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the HSR subgrade under cyclic load was further established. The backward Euler method was used to discretize the constitutive equation, build a numerical algorithm of “elastic prediction and plastic modification” and make a secondary development of the program to solve the cyclic compaction model.

Through the comparison with the result of laboratory triaxial test under the cyclic loading of coarse-grained soil filler for the HSR subgrade, the accuracy and applicability of the cyclic compaction model were verified. Results show that the model can accurately predict the cumulative deformation characteristics of coarse-grained soil filler for the HSR subgrade under the train vibration loading repeatedly for a long time. It considers the effects of particle breakage and stress ratio, which can be used to calculate and analyze the stress and deformation evolution law of the subgrade structure for HSR.

The research can provide a simple and practical method for calculating deformation of railway under cyclic loading.

The stress–strain behaviors of rockfill materials in dams are significantly affected by the anisotropy and grain crushing. However, these factors are rarely considered in numerical simulations of high rockfill dams. This study intends to develop a reasonable and practical constitutive model for rockfill materials to overcome the above problems.

The effects of anisotropy and grain crushing are comprehensively considered by the spatial position of the reference state line. After the improved generalized plasticity model for rockfill materials (referred to as the PZR model) is developed and verified by laboratory tests, it is used with the finite element method to simulate the stress–strain behaviors of the Nuozhadu high core rockfill dam.

The simulated results agree well with the laboratory tests data and the situ monitoring data, verifying the reliability and practicability of the developed PZR model.

A new anisotropic state parameter is proposed to reflect the nonmonotonic variation in the strength as the major principal stress direction angle varies. This advantage is verified by the simulation of a set of conventional triaxial tests with different inclination angles of the compaction plane. 2) This is the first time that the elastoplastic model is verified by the situ monitoring data of high core rockfill dams. The numerical simulation results show that the PZR model can well reflect the stress–strain characteristics of rockfill materials in high core rockfill dams and is better than the traditional EB model.

The grain size and grain distribution mode have a significant impact on the tribological properties of Babbitt alloy. The purpose of this paper is to study the effect of differentiated SnSb grain size distribution on the improvement of tribological properties of Babbitt alloy.

Babbitt (marked by babbitt-cr), with a differentiated SnSb grain size distribution, was fabricated using a selective zone laser surface treatment. Bare Babbitt with coarse SnSb grain was marked as babbitt-c, and Babbitt with refined SnSb grain was marked as babbitt-r. The microstructure, microhardness and wettability of specimens were tested. The tribological properties of babbitt-c, babbitt-r and babbitt-cr were evaluated under dry and lubricated conditions.

The microstructure transforms from single coarse SnSb grain distribution or single refined SnSb grain distribution to differentiated SnSb grain size distribution, as a result of selective zone laser surface treatment. Among three specimens of microhardness, babbitt-cr showed the highest microhardness. The lipophilicity property of babbitt-cr was better compared to babbitt-c. A mixture of coarse and refined grain is beneficial to improve the tribological properties of Babbitt alloy under dry condition. Furthermore, compared with babbitt-c, the wear resistance of babbitt-cr was enhanced under lubricated condition. However, the anti-wear property of babbitt-cr was not significantly improved relative to babbitt-r with an increase in the loads.

The study demonstrates that modulated different grain size alternating distribution modes can improve the tribological properties of Babbitt alloy.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2022-0259/

Some misconception appears to have arisen in respect to the meaning of Section 11 of the Food and Drugs Act, 1899, owing, doubtless, to the faulty punctuation of certain copies of the Act, and the Sanitary Record has done good service by calling attention to the matter. The trouble has clearly been caused by the insertion of a comma after the word “condensed” in certain copies of the Act, and the non‐insertion of this comma in other copies. The words of the section, as printed by the Sanitary Record, are as follows: “Every tin or other receptacle containing condensed, separated or skimmed milk must bear a label clearly visible to the purchaser on which the words ‘Machine‐skimmed Milk,’ or ‘Skimmed Milk,’ as the case may require, are printed in large and legible type.”

The purpose of this paper is to examine the relationship between food security and cleaner energy and evaluate the financial viability of both ethanol and biodiesel productions in Southern Brazil, the current battleground region among food, ethanol and biodiesel. Southeastern Brazil was chosen to carry the analyses because that is the current battleground region for food, ethanol and biodiesel.

The analyses to be carried out encompass the following steps: evaluate the investment needs for the ethanol and biodiesel programs in Southeast Brazil; gather information on financial costs, converting them to economic costs to evaluate the economic desirability of the programs; evaluate the possible subsidy needed to fulfill the programs' goals; and evaluate the biofuel‐food tradeoff under some different scenarios.

The conclusion is that Brazil, despite being the most efficient producer of ethanol, may very well be forced to use compensatory subsidies for ethanol production if the USA persists in imposing importing tariffs on that Brazilian commodity. On food security matters, the production of ethanol has to compete with beef production, whose prices present a rising trend because of strong demand in emerging countries. For the same reason biodiesel becomes less viable the stronger the demand for vegetable oil.

The competition among these three alternative uses of natural resources will become tougher in the coming decades as, on the one hand, consumption of food and energy increases at high rates. Developed countries, on the other hand, continue to be heavy polluters and at the same time create all sorts of obstacles to the expansion of food and clean energy production elsewhere.

A numerical analysis of the micromechanical behaviour of a granular material is described using a new program MASOM based on Cundall's discrete element method. In the analysis the individual grains which make up the material are taken to be deformable 2D polygons of arbitrary size and shape. Contact forces between the grains are calculated according to Mindlin's solution for frictional contact between elastic bodies. The material in each grain is taken to be linear elastic but limited by the fracture strength of the material. Fracture is permitted along any one of a number of candidate fracture planes if an associated compressive load tending to split the gain reaches a critical level. Fragments of fractured grains are carried until they become too small to track using the explicit time integration algorithm used to advance the solution. The MASOM program is able to consider a number of different classes of elements and different types of contact between the various classes. Thus, in addition to the granular material the program can also model containers and loading devices. The program is used to simulate uniaxial and triaxial compression tests for geological materials. The results are shown to give results for stress‐strain and stress difference versus pressure which are in qualitative agreement with test data. The numerical results reveal a very complex micromechanical behaviour in granular materials, including highly variable and rather unstable load paths and a very inhomogeneous load distribution within a representative sample of the material. A video of the response of a typical frictional material to applied loads shows an interesting localized effect near sample boundaries involving crowding together of grains which cannot be observed using conventional static field plots.

With the rapid growth and increased consumption of biofuels worldwide, and the multitude of policy decisions supporting this expansion, growing concerns about the biofuels sustainability have arisen. Therefore, the European project “ITAKA”, aiming at supporting the development of aviation biofuels in an economically, socially and environmentally sustainable manner, has devoted considerable effort to take sustainability into account, in a quantitative and qualitative manner. This paper aims to calculate a robust assessment of a life-cycle greenhouse gas (GHG) for the entire ITAKA value chain.

The calculation for the produced bio jet fuel has been set up using the roundtable on sustainable biomaterials (RSB) European Union (EU) renewable energy directive (RED) methodology, through the online RSB tool. This pathway includes feedstock production, feedstock processing, biofuel production, biofuel distillation and all transport steps involved.

A significant reduction in GHG emissions has been demonstrated, up to 66 per cent emission reduction if one considers a mature pathway for the entire ITAKA biofuel chain.

The camelina oil produced can be sustainable according to RSB and RSB EU RED schemes if the practices defined in the project are applied.

Application of different frameworks (actual vs theoretical) to the ITAKA value chain has aimed at testing and demonstrating the commercial application of the sustainability standards in Europe and the readiness of biofuels in Europe as a major means to decrease GHG emissions in aviation.

The information which has hitherto appeared in the daily press as to the evidence laid before the Departmental Committee which is inquiring into the use of preservatives and colouring matters can hardly have afforded pleasant reading to the apologists for the drugging of foods. It is plainly the intention of the Committee to make a thorough investigation of the whole subject, and the main conclusions which, in the result, must bo forced upon unbiassed persons by an investigation of this character will be tolerably obvious to those who have given serious attention to the subject. At a later stage of the inquiry we shall publish a full account of the evidence submitted and of the Committee's proceedings. At present we may observe that the facts which have been brought forward fully confirm the statements made from time to time upon these matters in the BRITISH FOOD JOURNAL, and amply justify the attitude which we have adopted on the whole question. Representatives of various trade interests have given evidence which has served to show the extent to which the practices now being inquired into are followed. Strong medical evidence, as to the dangers which must attach to the promiscuous and unacknowledged drugging of the public by more or less ignorant persons, has been given; and some medical evidence of that apologetic order to which the public have of late become accustomed, and which we, at any rate, regard as particularly feeble, has also been put forward. Much more will no doubt be said, but those who have borne the heat and burden of the day in forcing these matters upon the attention of the Legislature and of the public can view with satisfaction the result already attained. Full and free investigation must produce its educational effect ; and whatever legal machinery may be devised to put some kind of check upon these most dangerous forms of adulteration, the demand of the public will be for undrugged food, and for a guarantee of sufficient authority to ensure that the demand is met.

Lignite coal-fired power plants are the main electricity generators in the province of Saskatchewan, Canada. Although burning lignite coal to generate power is economical, it produces significant greenhouse gases making it a big challenge to Canada’s international commitment on emission reduction. However, abundant agricultural crops and sawdust produced in Saskatchewan put the province in a good position to produce and use agri-pellets as an alternative fuel to generate electricity. This study aims to conduct an economic and environmental analysis of the replacement of lignite coal by agri-pellets as the fuel for Saskatchewan’s coal-fired power plants.

The study estimates the economic and environmental costs and benefits of two alternative fuels for power plants. The economic analysis is based on the pellet production and transportation costs from farms to production sites and from the production sites to power plants. In the production process, biomass precursors are densified with and without additives to produce fuel agri-pellets with appropriate mechanical durability and high heating value per volume unit. The environmental analysis involves estimation of greenhouse gas emissions and their social costs for lignite coal and different types of agri-pellets under different scenarios for pellet production and transportation.

The results show that although the total cost of electricity is lower for coal than agri-pellets, the gap shrinks when social costs and specifically a carbon price of $50/tonne are included in the model. The cost of electricity in lignite coal-fired power plants would also be on par with agri-pellets-fired power plants if the carbon price is between U$68 and $78 per tonne depending on the power plant locations. Therefore, a transition from coal to agri-pellet fuels is feasible if a high-enough price is assigned to carbon. The method and the results can be generalized to other places with similar conditions.

There are a few caveats in this study as follows. First, the fixed costs associated with the transformation of the existing coal-fired power plants to pellet-fired plants are not considered. Second, the technological progress in the transportation sector, which would favor the net benefits of using pellets versus coal, is not included in the analysis. Finally, the study does not address the possible political challenges facing the transition in the context of the Canadian federal system.

The study results indicate that the current carbon price of $50 per tonne is not sufficient to make the agri-pellets a feasible source of alternative energy in Saskatchewan. However, if carbon pricing continues to rise by $15 annually starting in 2022, as announced, a transition from coal to agri-pellets will be economically feasible.

Canada is committed to reduce its emission according to the Paris agreement, and therefore, needs to have a concrete policy to find alternative energy sources for its coal-fired power plants. This study examines the challenges and benefits of such transition using the existing agri-pellet resources in Saskatchewan, a province with abundant agricultural residues and coal-fired power plants. The findings indicate that a significant emission reduction can be achieved by using agri-pellets instead of coal to produce electricity. The study also implies that the transition to renewable energy is economical when social costs of carbon (carbon tax) is included in the analysis.

As far as the authors know, this is the first study providing a socio-economic analysis for a possible transition from the coal-fired power plants to a more clean and sustainable renewable energy source in one of the highest carbon dioxide (CO₂) producer provinces in Canada: Saskatchewan. The study builds upon the technical production of three agri-pellets (oat hull, canola hull and sawdust) and estimates the economic and environmental costs of alternative fuels under different scenarios.

The paper aims to introduce the fabrication of a medium steel aircraft part by hybrid deposition and micro-rolling technology (HDMR) and illustrate its advantages, microstructure features and mechanical properties of the part.

The HDMR technology contains two procedures happening almost at the same time: the welding deposition procedure and then the micro-rolling procedure. It takes the gas metal arc welding as the heat source to melt a metal wire and deposit metal in the welding deposition procedure. The metal just deposited is rolled synchronously by a micro roller following the welding torch in micro-rolling procedure almost at the same time layer by layer. The paper presents a contrast of the grain morphology of metal parts produced respectively by HDMR and freedom arc deposition (FAD) and the mechanical properties of metal parts of the same metal from HDMR casting, forging and FAD methods.

HDMR breaks the dendrite grain of welding beads into the fine crisscross grains. The mechanical properties of metal parts are improved distinctly by the micro-rolling procedure compared to casting, forging and FAD.

In addition, the application of HDMR technology has succeeded in the fabrication of an eligible aircraft metal part, which is quite difficult to achieve using other additive manufacturing (AM) or casting technologies.

HDMR has the advantage of equiponderance manufacturing by micro-rolling compared to other AM technologies. The metal part fabricated by HDMR technology obtains the fine crisscross grains and brings hope for AM metal components with excellent mechanical properties for aircraft applications.