bluuebunny/crossref_metadata_2025 huggingface dataset:
A Ti/Pt/Co Multilayer Stack for Transfer Function Based Magnetic Force Microscopy Calibrations
Authors: Sakar Baha , Sievers Sibylle , Fernández Scarioni Alexander , Garcia-Sanchez Felipe , Öztoprak İlker , Schumacher Hans Werner , Öztürk Osman
Published: June 2021

Magnetic force microscopy (MFM) is a widespread technique for imaging magnetic structures with a resolution of some 10 nanometers. MFM can be calibrated to obtain quantitative (qMFM) spatially resolved magnetization data in units of A/m by determining the calibrated point spread function of the instrument, its instrument calibration function (ICF), from a measurement of a well-known reference sample. Beyond quantifying the MFM data, a deconvolution of the MFM image data with the ICF also corrects the smearing caused by the finite width of the MFM tip stray field distribution. However, the quality of the calibration depends critically on the calculability of the magnetization distribution of the reference sample. Here, we discuss a Ti/Pt/Co multilayer stack that shows a stripe domain pattern as a suitable reference material. A precise control of the fabrication process, combined with a characterization of the sample micromagnetic parameters, allows reliable calculation of the sample’s magnetic stray field, proven by a very good agreement between micromagnetic simulations and qMFM measurements. A calibrated qMFM measurement using the Ti/Pt/Co stack as a reference sample is shown and validated, and the application area for quantitative MFM measurements calibrated with the Ti/Pt/Co stack is discussed.
An Optimized Triggering Algorithm for Event-Triggered Control of Networked Control Systems
Authors: Mishra Sunil Kumar , Jha Amitkumar V. , Verma Vijay Kumar , Appasani Bhargav , Abdelaziz Almoataz Y. , Bizon Nicu
Published: June 2021

This paper presents an optimized algorithm for event-triggered control (ETC) of networked control systems (NCS). Initially, the traditional backstepping controller is designed for a generalized nonlinear plant in strict-feedback form that is subsequently extended to the ETC. In the NCS, the controller and the plant communicate with each other using a communication network. In order to minimize the bandwidth required, the number of samples to be sent over the communication channel should be reduced. This can be achieved using the non-uniform sampling of data. However, the implementation of non-uniform sampling without a proper event triggering rule might lead the closed-loop system towards instability. Therefore, an optimized event triggering algorithm has been designed such that the system states are always forced to remain in stable trajectory. Additionally, the effect of ETC on the stability of backstepping control has been analyzed using the Lyapunov stability theory. Two case studies on an inverted pendulum system and single-link robot system have been carried out to demonstrate the effectiveness of the proposed ETC in terms of system states, control effort and inter-event execution time.
Channel Strategies for the Two-Period Closed-Loop Supply Chain with E-Commerce
Authors: Zhao Lin , Mu Zongyu
Published: June 2021

The aim of this paper is to choose the effective selling channel and reverse channel for a closed-loop supply chain (CLSC) with the e-commerce. The authors formulated six single-selling and dual-selling channel two-period CLSC models in which the manufacturer manufactures new products in the first period and then collects used products by itself, outsourcing to or cooperating with the retailer in the second period. Some interesting and new insights obtained from comparison analysis and numerical experiments are as follows: (1) The leading manufacturer ought to add e-commerce channel, and customers’ e-commerce preference can increase the market demand, collecting rate, and manufacturer’s profit. (2) With the e-commerce channel and the retail channel, dual-collecting channel is the best for the manufacturer and system while the manufacturer collecting channel becomes the best when the collecting competition is relatively large. When the collecting competition exists, retailer collecting channel is the best for the retailer. (3) The market demand, collecting rate, the profits of all members and system will rise by increasing the remanufacturing level and discount coefficient.
Geometrical Properties of the Pseudonull Hypersurfaces in Semi-Euclidean 4-Space
Authors: Sun Jianguo , Jiang Xiaoyan , Ji Fenghui
Published: June 2021

In this paper, we focus on some geometrical properties of the partially null slant helices in semi-Euclidean 4-space. By structuring suitable height functions, we obtain the singularity types of the pseudonull hypersurfaces, which are generated by the partially null slant helices. An example is given to determine the main results.
γ-Valerolactone as Bio-Based Solvent for Nanofiltration Membrane Preparation
Authors: Rasool Muhammad Azam , Vankelecom Ivo F. J.
Published: June 2021

γ-Valerolactone (GVL) was selected as a renewable green solvent to prepare membranes via the process of phase inversion. Water and ethanol were screened as sustainable non-solvents to prepare membranes for nanofiltration (NF). Scanning electron microscopy was applied to check the membrane morphology, while aqueous rose Bengal (RB) and magnesium sulphate (MgSO4) feed solutions were used to screen performance. Cellulose acetate (CA), polyimide (PI), cellulose triacetate (CTA), polyethersulfone (PES) and polysulfone (PSU) membranes were fine-tuned as materials for preparation of NF-membranes, either by selecting a suitable non-solvent for phase inversion or by increasing the polymer concentration in the casting solution. The best membranes were prepared with CTA in GVL using water as non-solvent: with increasing CTA concentration (10 wt% to 17.5 wt%) in the casting solution, permeance decreased from 15.9 to 5.5 L/m2·h·bar while RB rejection remained higher than 94%. The polymer solubilities in GVL were rationalized using Hansen solubility parameters, while membrane performances and morphologies were linked to viscosity measurements and cloudpoint determination of the casting solutions to better understand the kinetic and thermodynamic aspects of the phase inversion process.
Interfacial Design of Mixed Matrix Membranes via Grafting PVA on UiO-66-NH2 to Enhance the Gas Separation Performance
Authors: Ashtiani Saeed , Khoshnamvand Mehdi , Regmi Chhabilal , Friess Karel
Published: June 2021

In this study, defect-free facilitated transport mixed matrix membrane (MMM) with high loading amount of UiO-66-NH2 nanoparticles as metal–organic frameworks (MOFs) was fabricated. The MOFs were covalently bonded with poly (vinyl alcohol) (PVA) to incorporate into a poly (vinyl amine) (PVAm) matrix solution. A uniform UiO-66-NH2 dispersion up to 55 wt.% was observed without precipitation and agglomeration after one month. This can be attributed to the high covalent interaction at interfaces of UiO-66-NH2 and PVAm, which was provided by PVA as a functionalized organic linker. The CO2 permeability and CO2/N2 and selectivity were significantly enhanced for the fabricated MMM by using optimal fabrication parameters. This improvement in gas performance is due to the strong impact of solubility and decreasing diffusion in obtained dense membrane to promote CO2 transport with a bicarbonate reversible reaction. Therefore, the highest amount of amine functional groups of PVAm among all polymers, plus the abundant amount of amines from UiO-66-NH2, facilitated the preferential CO2 permeation through the bicarbonate reversible reaction between CO2 and –NH2 in humidified conditions. XRD and FTIR were employed to study the MMM chemical structure and polymers–MOF particle interactions. Cross-sectional and surface morphology of the MMM was observed by SEM-EDX and 3D optical profilometer to detect the dispersion of MOFs into the polymer matrix and explore their interfacial morphology. This approach can be extended for a variety of polymer–filler interfacial designs for gas separation applications.
Chitosan as a Coating for Biocontrol in Postharvest Products: A Bibliometric Review
Authors: Salgado-Cruz Ma de la Paz , Salgado-Cruz Julia , García-Hernández Alitzel Belem , Calderón-Domínguez Georgina , Gómez-Viquez Hortensia , Oliver-Espinoza Rubén , Fernández-Martínez María Carmen , Yáñez-Fernández Jorge
Published: June 2021

The aim of this work was to carry out a systematic literature review focused on the scientific production, trends, and characteristics of a knowledge domain of high worldwide importance, namely, the use of chitosan as a coating for postharvest disease biocontrol in fruits and vegetables, which are generated mainly by fungi and bacteria such as Aspergillus niger, Rhizopus stolonifera, and Botrytis cinerea. For this, the analysis of 875 published documents in the Scopus database was performed for the years 2011 to 2021. The information of the keywords’ co-occurrence was visualized and studied using the free access VOSviewer software to show the trend of the topic in general. The study showed a research increase of the chitosan and nanoparticle chitosan coating applications to diminish the postharvest damage by microorganisms (fungi and bacteria), as well as the improvement of the shelf life and quality of the products.
Control Over the Morphology of Electrospun Microfibrous Mats of a Polymer of Intrinsic Microporosity
Authors: Lasseuguette Elsa , Malpass-Evans Richard , Tobin John M. , McKeown Neil B. , Ferrari Maria-Chiara
Published: June 2021

This study reports for the first time the preparation of an electrospun microfibrous mat of PIM-EA-TB. The electrospinning was carried out using a chloroform/n-Propyl-lactate (n-PL) binary solvent system with different chloroform/nPL ratios, in order to control the morphology of the microfibres. With pure chloroform, porous and dumbbell shape fibres were obtained whereas, with the addition on n-PL, circular and thinner fibres have been produced due to the higher boiling point and the higher conductivity of n-PL. The electrospinning process conditions were investigated to evaluate their impact on the fibres’ morphology. These microfibrous mats presented potential to be used as breathable/waterproof materials, with a pore diameter of 11 μm, an air resistance of 25.10−7 m−1 and water breakthrough pressure of 50 mBar.
Recycling and Separation of Homogeneous Catalyst from Aqueous Multicomponent Mixture by Organic Solvent Nanofiltration
Authors: Schnoor J.-Kilian , Bettmer Jens , Kamp Johannes , Wessling Matthias , Liauw Marcel A.
Published: June 2021

Organic solvent nanofiltration (OSN) has evolved to an established recycling method for homogeneous catalysts. However, commercial availability has not circumvented the need for classification and the scoping of possible applications for specific solvent mixtures. Therefore, Evonik’s DuraMem® 300 was assessed for the recycling of magnesium triflate at two transmembrane pressures from a mixture of ethanol, ethyl acetate and water. Catalyst retention up to 98% and permeability of up to 4.44·10−1∙L∙bar−1∙m−2∙h−1 were possible when less than 25% ethyl acetate was in the mixture. The retention of some of the components in the ternary mixture was observed while others were enriched, making the membrane also suitable for fractioning thereof.
A Modular Approach for a Patient Unit for Extracorporeal Membrane Oxygenation Simulator
Authors: Alhomsi Yahya , Alsalemi Abdullah , Noorizadeh Mohammad , Bensaali Faycal , Meskin Nader , Hssain Ali Ait
Published: June 2021

Despite many advancements in extracorporeal membrane oxygenation (ECMO), the procedure is still correlated with a high risk of patient complications. Simulation-based training provides the opportunity for ECMO staff to practice on real-life scenarios without exposing ECMO patients to medical errors while practicing. At Hamad Medical Corporation (HMC) in Qatar, there is a critical need of expert ECMO staff. Thus, a modular ECMO simulator is being developed to enhance the training process in a cost-effective manner. This ECMO simulator gives the instructor the ability to control the simulation modules and run common simulation scenarios through a tablet application. The core modules of the simulation system are placed in the patient unit. The unit is designed modularly such that more modules can be added throughout the simulation sessions to increase the realism of the simulation sessions. The new approach is to enclose the patient unit in a trolley, which is custom-designed and made to include all the components in a modular fashion. Each module is enclosed in a separate box and then mounted to the main blood simulation loop box using screws, quick connect/disconnect liquid fittings, and electrical plugs. This method allows fast upgrade and maintenance for each module separately as well as upgrading modules easily without modifying the trolley’s design. The prototype patient unit has been developed for portability, maintenance, and extensibility. After implementation and testing, the prototype has proven to successfully simulate the main visual and audio cues of the real emergency scenarios, while keeping costs to a minimum.
Measurement of Exhaled Nitric Oxide in 456 Lung Cancer Patients Using a Ringdown FENO Analyzer
Authors: Li Jing , Li Qingyuan , Wei Xin , Chen Qing , Sun Meixiu , Li Yingxin
Published: June 2021

The objective of this study was to investigate the clinical value of exhaled nitric oxide (NO) for diagnosing lung cancer patients by using a relatively large sample. An online and near-real-time ringdown exhaled NO analyzer calibrated by an electrochemical sensor at clinical was used for breath analysis. A total of 740 breath samples from 284 healthy control subjects (H) and 456 lung cancer patients (LC) were collected. The recorded data included exhaled NO, medications taken within the last half month, demographics, fasting status and smoking status. The LC had a significantly higher level of exhaled NO than the H (H: 21.0 ± 12.1 ppb vs. LC: 34.1 ± 17.2 ppb). The area under the receiver operating characteristic curve for exhaled NO predicting LC and H was 0.728 (sensitivity was 0.798; specificity was 0.55). There was no significant difference in exhaled NO level between groups divided by different types of LC, tumor node metastasis (TNM) stage, sex, smoking status, age, body mass index (BMI) or fasting status. Exhaled NO level alone is not a useful clinical tool for identifying lung cancer, but it should be considered when developing a diagnosis model of lung cancer by using breath analysis.
Gut Microbiome and Metabolites in Patients with NAFLD and after Bariatric Surgery: A Comprehensive Review
Authors: Hoozemans Jacqueline , de Brauw Maurits , Nieuwdorp Max , Gerdes Victor
Published: June 2021

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing, as are other manifestations of metabolic syndrome such as obesity and type 2 diabetes. NAFLD is currently the number one cause of chronic liver disease worldwide. The pathophysiology of NAFLD and disease progression is poorly understood. A potential contributing role for gut microbiome and metabolites in NAFLD is proposed. Currently, bariatric surgery is an effective therapy to prevent the progression of NAFLD and other manifestations of metabolic syndrome such as obesity and type 2 diabetes. This review provides an overview of gut microbiome composition and related metabolites in individuals with NAFLD and after bariatric surgery. Causality remains to be proven. Furthermore, the clinical effects of bariatric surgery on NAFLD are illustrated. Whether the gut microbiome and metabolites contribute to the metabolic improvement and improvement of NAFLD seen after bariatric surgery has not yet been proven. Future microbiome and metabolome research is necessary for elucidating the pathophysiology and underlying metabolic pathways and phenotypes and providing better methods for diagnostics, prognostics and surveillance to optimize clinical care.
Novel Multilayer SAW Temperature Sensor for Ultra-High Temperature Environments
Authors: Zhou Xuhang , Tan Qiulin , Liang Xiaorui , Lin Baimao , Guo Tao , Gan Yu
Published: June 2021

Performing high-temperature measurements on the rotating parts of aero-engine systems requires wireless passive sensors. Surface acoustic wave (SAW) sensors can measure high temperatures wirelessly, making them ideal for extreme situations where wired sensors are not applicable. This study reports a new SAW temperature sensor based on a langasite (LGS) substrate that can perform measurements in environments with temperatures as high as 1300 °C. The Pt electrode and LGS substrate were protected by an AlN passivation layer deposited via a pulsed laser, thereby improving the crystallization quality of the Pt film, with the function and stability of the SAW device guaranteed at 1100 °C. The linear relationship between the resonant frequency and temperature is verified by various high-temperature radio-frequency (RF) tests. Changes in sample microstructure before and after high-temperature exposure are analyzed using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The analysis confirms that the proposed AlN/Pt/Cr thin-film electrode has great application potential in high-temperature SAW sensors.
Integrated Resonant Micro/Nano Gravimetric Sensors for Bio/Chemical Detection in Air and Liquid
Authors: Jia Hao , Xu Pengcheng , Li Xinxin
Published: June 2021

Resonant micro/nanoelectromechanical systems (MEMS/NEMS) with on-chip integrated excitation and readout components, exhibit exquisite gravimetric sensitivities which have greatly advanced the bio/chemical sensor technologies in the past two decades. This paper reviews the development of integrated MEMS/NEMS resonators for bio/chemical sensing applications mainly in air and liquid. Different vibrational modes (bending, torsional, in-plane, and extensional modes) have been exploited to enhance the quality (Q) factors and mass sensing performance in viscous media. Such resonant mass sensors have shown great potential in detecting many kinds of trace analytes in gas and liquid phases, such as chemical vapors, volatile organic compounds, pollutant gases, bacteria, biomarkers, and DNA. The integrated MEMS/NEMS mass sensors will continuously push the detection limit of trace bio/chemical molecules and bring a better understanding of gas/nanomaterial interaction and molecular binding mechanisms.
Highly Sensitive Hybrid Nanostructures for Dimethyl Methyl Phosphonate Detection
Authors: Lama Sanjeeb , Kim Jinuk , Ramesh Sivalingam , Lee Young-Jun , Kim Jihyun , Kim Joo-Hyung
Published: June 2021

Nanostructured materials synthesized by the hydrothermal and thermal reduction process were tested to detect the dimethyl methylphosphonate (DMMP) as a simulant for chemical warfare agents. Manganese oxide nitrogen-doped graphene oxide with polypyrrole (MnO2@NGO/PPy) exhibited the sensitivity of 51 Hz for 25 ppm of DMMP and showed the selectivity of 1.26 Hz/ppm. Nitrogen-doped multi-walled carbon nanotube (N-MWCNT) demonstrated good linearity with a correlation coefficient of 0.997. A comparison between a surface acoustic wave and quartz crystal microbalance sensor exhibited more than 100-times higher sensitivity of SAW sensor than QCM sensor.
Direct Mercury Detection in Landfill Leachate Using a Novel AuNP-Biopolymer Carbon Screen-Printed Electrode Sensor
Authors: Hwang Jae-Hoon , Fox David , Stanberry Jordan , Anagnostopoulos Vasileios , Zhai Lei , Lee Woo Hyoung
Published: June 2021

A novel Au nanoparticle (AuNP)-biopolymer coated carbon screen-printed electrode (SPE) sensor was developed through the co-electrodeposition of Au and chitosan for mercury (Hg) ion detection. This new sensor showed successful Hg2+ detection in landfill leachate using square wave anodic stripping voltammetry (SWASV) with an optimized condition: a deposition potential of −0.6 V, deposition time of 200 s, amplitude of 25 mV, frequency of 60 Hz, and square wave step voltage of 4 mV. A noticeable peak was observed at +0.58 V associated with the stripping current of the Hg ion. The sensor exhibited a good sensitivity of ~0.09 μA/μg (~0.02 μA/nM) and a linear response over the concentration range of 10 to 100 ppb (50–500 nM). The limit of detection (LOD) was 1.69 ppb, which is significantly lower than the safety limit defined by the United States Environmental Protection Agency (USEPA). The sensor had an excellent selective response to Hg2+ in landfill leachate against other interfering cations (e.g., Zn2+, Pb2+, Cd2+, and Cu2+). Fifteen successive measurements with a stable peak current and a lower relative standard deviation (RSD = 5.1%) were recorded continuously using the AuNP-biopolymer-coated carbon SPE sensor, which showed excellent stability, sensitivity and reproducibility and consistent performance in detecting the Hg2+ ion. It also exhibited a good reliability and performance in measuring heavy metals in landfill leachate.
Spin-Mechanics with Nitrogen-Vacancy Centers and Trapped Particles
Authors: Perdriat Maxime , Pellet-Mary Clément , Huillery Paul , Rondin Loïc , Hétet Gabriel
Published: June 2021

Controlling the motion of macroscopic oscillators in the quantum regime has been the subject of intense research in recent decades. In this direction, opto-mechanical systems, where the motion of micro-objects is strongly coupled with laser light radiation pressure, have had tremendous success. In particular, the motion of levitating objects can be manipulated at the quantum level thanks to their very high isolation from the environment under ultra-low vacuum conditions. To enter the quantum regime, schemes using single long-lived atomic spins, such as the electronic spin of nitrogen-vacancy (NV) centers in diamond, coupled with levitating mechanical oscillators have been proposed. At the single spin level, they offer the formidable prospect of transferring the spins’ inherent quantum nature to the oscillators, with foreseeable far-reaching implications in quantum sensing and tests of quantum mechanics. Adding the spin degrees of freedom to the experimentalists’ toolbox would enable access to a very rich playground at the crossroads between condensed matter and atomic physics. We review recent experimental work in the field of spin-mechanics that employ the interaction between trapped particles and electronic spins in the solid state and discuss the challenges ahead. Our focus is on the theoretical background close to the current experiments, as well as on the experimental limits, that, once overcome, will enable these systems to unleash their full potential.
Parasitic Intestinal Protists of Zoonotic Relevance Detected in Pigs by Metabarcoding and Real-Time PCR
Authors: Stensvold Christen Rune , Jirků-Pomajbíková Kateřina , Tams Katrine Wegener , Jokelainen Pikka , Berg Rebecca P. K. D. , Marving Ellinor , Petersen Randi Føns , Andersen Lee O’Brien , Angen Øystein , Nielsen Henrik Vedel
Published: June 2021

Several parasite species are shared between humans and pigs. We explored the application of next-generation sequencing-based metabarcoding supplemented with real-time PCR to fecal DNAs from 259 samples from 116 pigs in Denmark to detect and differentiate single-celled intestinal parasites of zoonotic relevance. Enterocytozoon bieneusi, Balantioides coli, and Giardia duodenalis were observed in 34/37 (92%), 148/259 (57%), and 86/259 (33%) samples, respectively. Entamoeba polecki ST1, E. polecki ST3, and Entamoeba hartmanni were detected in 104/259 (40%), 161/259 (62%), and 8/259 (3%) samples, respectively. Metabarcoding and real-time PCR detected Cryptosporidium in 90/259 (35%) and 239/259 (92%) of the samples, respectively, with Cryptosporidium suis and Cryptosporidium scrofarum observed in nearly equal proportions. Blastocystis subtypes 1, 3, 5, and 15 were found in 72 (28%), 6 (2%), 176 (68%), and 36 (14%) of 259 samples, respectively. Iodamoeba was identified in 1/259 samples (<1%), while none of 37 tested samples was positive for Dientamoeba fragilis. Our results illustrate how metabarcoding exemplifies a ‘one-fits-many’ approach to detecting intestinal single-celled parasites in feces supplemented with real-time PCR for selected parasites. Using metabarcoding with pathogen-specific assays may help detect emerging and previously underdetected pathogens and further elucidate the role of micro-eukaryotic parasites in human and animal health and disease.
Morinagadepsin, a Depsipeptide from the Fungus Morinagamyces vermicularis gen. et comb. nov.
Authors: Harms Karen , Surup Frank , Stadler Marc , Stchigel Alberto Miguel , Marin-Felix Yasmina
Published: June 2021

The new genus Morinagamyces is introduced herein to accommodate the fungus Apiosordaria vermicularis as inferred from a phylogenetic study based on sequences of the internal transcribed spacer region (ITS), the nuclear rDNA large subunit (LSU), and partial fragments of ribosomal polymerase II subunit 2 (rpb2) and β-tubulin (tub2) genes. Morinagamyces vermicularis was analyzed for the production of secondary metabolites, resulting in the isolation of a new depsipeptide named morinagadepsin (1), and the already known chaetone B (3). While the planar structure of 1 was elucidated by extensive 1D- and 2D-NMR analysis and high-resolution mass spectrometry, the absolute configuration of the building blocks Ala, Val, and Leu was determined as -l by Marfey’s method. The configuration of the 3-hydroxy-2-methyldecanyl unit was assigned as 22R,23R by J-based configuration analysis and Mosher’s method after partial hydrolysis of the morinagadepsin to the linear derivative compound 2. Compound 1 showed cytotoxic activity against the mammalian cell lines KB3.1 and L929, but no antimicrobial activity against the fungi and bacteria tested was observed, while 2 was inactive. Compound 3 was weakly cytotoxic against the cell line L929, but did not show any antimicrobial activity.
Recovery of Zinc and Silver from Zinc Acid-Leaching Residues with Reduction of Their Environmental Impact Using a Novel Water Leaching-Flotation Process
Authors: Du Yunpeng , Tong Xiong , Xie Xian , Zhang Wenjie , Yang Hanxu , Song Qiang
Published: June 2021

Zinc-leaching residue (ZLR) is a strongly acidic hazardous waste; it has poor stability, high heavy metal levels, and releases toxic elements into the environment. ZLR has potential as a valuable resource, because it contains elevated levels of zinc and silver. In this paper, the recovery of zinc (Zn) and silver (Ag) from ZLR wastes from zinc hydrometallurgy workshops using water leaching followed by flotation was studied. During water leaching experiments, the zinc and copper recovery rates were 38% and 61%, respectively. Thereafter, various flotation testing parameters were optimized and included grinding time, reagent dosages, pulp density, flotation time, and type of adjuster. Experimental results demonstrated this flotation method successfully recycled Ag and Zn. A froth product containing more than 9256.41 g/t Ag and 12.26% Zn was produced from the ZLR with approximately 80.32% Ag and 42.88% Zn recoveries. The toxicity characteristic leaching procedure (TCLP) results indicated the water-leaching flotation process not only recycled valuable metals such as zinc and silver in zinc-containing hazardous wastes but lowered the hazardous waste levels to those of general wastes and recycled wastes in an efficient, economical, and environmentally friendly way.
Integrating Production Planning with Truck-Dispatching Decisions through Reinforcement Learning While Managing Uncertainty
Authors: de Carvalho Joao Pedro , Dimitrakopoulos Roussos
Published: June 2021

This paper presents a new truck dispatching policy approach that is adaptive given different mining complex configurations in order to deliver supply material extracted by the shovels to the processors. The method aims to improve adherence to the operational plan and fleet utilization in a mining complex context. Several sources of operational uncertainty arising from the loading, hauling and dumping activities can influence the dispatching strategy. Given a fixed sequence of extraction of the mining blocks provided by the short-term plan, a discrete event simulator model emulates the interaction arising from these mining operations. The continuous repetition of this simulator and a reward function, associating a score value to each dispatching decision, generate sample experiences to train a deep Q-learning reinforcement learning model. The model learns from past dispatching experience, such that when a new task is required, a well-informed decision can be quickly taken. The approach is tested at a copper–gold mining complex, characterized by uncertainties in equipment performance and geological attributes, and the results show improvements in terms of production targets, metal production, and fleet management.
Reaction and Alteration of Mudstone with Ordinary Portland Cement and Low Alkali Cement Pore Fluids
Authors: Bateman Keith , Amano Yuki , Kubota Mitsuru , Ohuchi Yuji , Tachi Yukio
Published: June 2021

The construction of a repository for the geological disposal of radioactive waste will utilize cement-based materials. Following closure, resaturation will result in the development of a highly alkaline porewater. The alkaline fluid will migrate and react with host rock, producing a chemically disturbed zone (CDZ) around the repository. To understand how these conditions may evolve, a series of batch and flow experiments were conducted with Horonobe mudstone and fluids representative of the alkaline leachates expected from a cementitious repository. Both ordinary Portland cement (OPC) and low alkali cement (LAC) leachates were examined. The impact of the LAC leachates was more limited than the OPC leachates, with experiments using the LAC leachate showing the least reaction and lowest long-term pH of the different leachate types. The reaction was dominated by primary mineral dissolution, and in the case of OPC leachates, precipitation of secondary calcium-silicate-hydrate (C-S-H) phases. Flow experiments revealed that precipitation of the secondary phases was restricted to close to the initial contact zone of the fluids and mudstone. The experimental results demonstrate that a combination of both batch and flow-through experiments can provide the insights required for the understanding of the key geochemical interactions and the impact of transport.
Process Evaluation of an Iron Ore Operation Using the Floatability Component Model
Authors: Geldenhuys Stefan , Pinto Thiago Souza , Filho Laurindo Leal , Deglon David
Published: June 2021

The Brucutu iron ore mine (Minas Gerais, Brazil) is Vale‘s largest iron producing operation achieving around 21 million tons per annum. Evaluation of flotation performance is of high importance as even small gains can lead to large monetary benefits. Cell-by-cell samples of the froth products, selected feed and pulp-products were analyzed for flow rate, particle size distribution and chemical composition. In addition, certain samples were analyzed on an assay-by-size basis and hydrodynamic measurements of certain flotation cells were also performed. This detailed experimental dataset was then used to calibrate a floatability component model of the process. Longer mainline residence time resulted in significant Fe2O3 losses while yielding little benefit in terms of SiO2 product grade. Scavenger 2 has twice the residence time of scavenger 1 while having to treat only 10% of the SiO2, resulting in high Fe2O3 recoveries to the froth and poor separation. In addition, it is shown that the Fe2O3 exhibits true flotation behavior resulting in increased Fe2O3 losses. Simulations using the floatability component model identified avenues of process improvement to address the identified behavior. The insight provided by the simulations into the dynamics of the flotation process is invaluable for process engineers.
Investigation on Mechanical Characteristics and Microstructure of Cemented Whole Tailings Backfill
Authors: Belibi Tana Armelle Estelle , Yin Shenghua , Wang Leiming
Published: June 2021

A paste backfill performance can be primarily evaluated through the mechanical and physical characteristics of the components involved. In this study, the effects of solid components’ tailings, binders and waters contents on microstructural evolution and mechanical properties of uncemented whole tailings backfill (CWTB) mixtures were investigated. Different mixtures of ordinary Portland cement of 1, 3 and 5 wt. % and solid concentrations at 72 wt. %, 74 wt. % and 75 wt. % were selected and rheological test was conducted to define the slump fluidity and yield stress. The microstructure of the solid component before and after the preparation and chemical composition were analyzed by the Scanning electron microscope and XRD analysis, respectively. The results show that a positive correlation between yield stress and slump values of CWTB paste slurries, the decrease of flow consistence leads to the reduction of the water content on the CWTB mixtures and the flow resistance of the paste. With the highest solids content, unconfined compressive strength (UCS) of CWTB varies between 0.1–0.9 MPa. Increasing the solid content affects the porosity and improves the strength resistance of CWTB mixtures. The findings in this study can therefore lead us to a statement that CWTB chemical components seem to be an important factor in cemented paste backfill (CPB) design and mine operations.
Characterisation of Industrial Side Streams and Their Application for the Production of Geopolymer Composites
Authors: Küçük Mehmet Emin , Kinnarinen Teemu , Timonen Juha , Mulari Olli , Häkkinen Antti
Published: June 2021

This study focuses on characterisation of side streams including biomass fly ash, biomass bottom ash, coal fly ash, green liquor dregs, limestone mine tailings, and electric arc furnace steel slag from different industrial locations in Finland. It was found that the fly ash samples contained the highest Al2O3 and SiO2 concentrations, a large number of spherical particles of small sizes and high specific surface areas. Fly ashes and steel slag were observed to contain higher amounts of amorphous phases compared to the other side streams. The high loss on ignition value of the coal fly ash and green liquor dregs was found to exceed the limitations for their application in geopolymer composites. Despite their relatively high concentrations in ashes and steel slag, the leaching tests have shown that no hazardous metal leached out from the streams. Finally, test specimens of geopolymer composites (GP2) were prepared by the application of biomass fly ash, bottom ash, and limestone mine tailings without any pre-treatment process, in addition to the ordinary Portland cement-(R) and metakaolin-based geopolymer composites (GP1). The measured compressive (14.1 MPa) and flexural strength (3.5 MPa) of GP2 suggest that it could be used in concrete kerbs and paving flags. The data has also shown that over 500% of the compressive strength was developed between 7 and 28 days in GP2, whereas in the case of reference concrete (R) and the metakaolin-based geopolymer composite (GP1) it was developed in the first 7 days.
Do Old Mining Areas Represent an Environmental Problem and Health Risk? A Critical Discussion through a Particular Case
Authors: Martínez-López Salvadora , Martínez-Sánchez María José , Pérez-Sirvent Carmen
Published: June 2021

A bibliographic review was carried out to establish the state of knowledge of a mining area with several centuries of exploitation and currently abandoned. The selected case study, the Sierra Minera de Cartagena-La Union (Spain), has a long history of mining activity, ending in 1990. The area is rich in metallic sulphide (lead, zinc and iron), with underground mines and quarries. The zone is very close to important populations and affects protected sites of special ecological value. It is also adjacent to areas dedicated to agriculture and important centres of tourist interest. It is a territory that meets the requirements to be classified as a critical area, as it is in a state of unstable physical and geochemical equilibrium, giving rise to possible risks to human health and ecosystems. A literature review was carried out according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology criteria, consulting a large number of related publications. The results obtained using the Source-Pathway-Receptor model make it possible to identify the main impacts caused by the contamination sources, the main routes of contamination, as well as the transfer to the biota and the influence on adjacent agricultural soils. In this study, lead, cadmium, zinc, arsenic, copper and manganese were considered as potential toxic elements (PTEs), and data were obtained on concentrations in soil, water and air as well as in fauna and flora. Finally, once the receptors and the associated risks to the ecosystem and human health were identified, a conceptual model of the contamination was drawn up to consider a management proposal to tackle the problems associated with this area, which would also be applicable to critical mining zones.
Use of Decision Trees for the Development of Decision Support Systems for the Control of Grinding Circuits
Authors: Olivier Jacques , Aldrich Chris
Published: June 2021

Grinding circuits can exhibit strong nonlinear behaviour, which may make automatic supervisory control difficult and, as a result, operators still play an important role in the control of many of these circuits. Since the experience among operators may be highly variable, control of grinding circuits may not be optimal and could benefit from automated decision support. This could be based on heuristics from process experts, but increasingly could also be derived from plant data. In this paper, the latter approach, based on the use of decision trees to develop rule-based decision support systems, is considered. The focus is on compact, easy to understand rules that are well supported by the data. The approach is demonstrated by means of an industrial case study. In the case study, the decision trees were not only able to capture operational heuristics in a compact intelligible format, but were also able to identify the most influential variables as reliably as more sophisticated models, such as random forests.
Spectral Tomography for 3D Element Detection and Mineral Analysis
Authors: Godinho Jose R. A. , Westaway-Heaven Gabriel , Boone Marijn A. , Renno Axel D.
Published: June 2021

This paper demonstrates the potential of a new 3D imaging technique, Spectral Computed Tomography (sp-CT), to identify heavy elements inside materials, which can be used to classify mineral phases. The method combines the total X-ray transmission measured by a normal polychromatic X-ray detector, and the transmitted X-ray energy spectrum measured by a detector that discriminates between X-rays with energies of about 1.1 keV resolution. An analysis of the energy spectrum allows to identify sudden changes of transmission at K-edge energies that are specific of each element. The additional information about the elements in a phase improves the classification of mineral phases from grey-scale 3D images that would be otherwise difficult due to artefacts or the lack of contrast between phases. The ability to identify the elements inside the minerals that compose ore particles and rocks is crucial to broaden the application of 3D imaging in Earth sciences research and mineral process engineering, which will represent an important complement to traditional 2D imaging mineral characterization methods. In this paper, the first applications of sp-CT to classify mineral phases are showcased and the limitations and further developments are discussed.
DESIDS: An Integrated Decision Support System for the Planning, Analysis, Management and Rehabilitation of Pressurised Irrigation Distribution Systems
Authors: Fouial Abdelouahid , Rodríguez Díaz Juan Antonio
Published: May 2021

Pressurized irrigation distribution systems (PIDSs) play a vital role in irrigation intensification, especially in the Mediterranean region. The design, operation and management of these systems can be complex, as they involve several intertwined processes which need to be considered simultaneously. For this reason, numerous decision support systems (DSSs) have been developed and are available to deal with these processes, but as independent components. To this end, a comprehensive DSS called DESIDS has been developed and tested. This DSS has been developed to bear in mind the needs of irrigation district managers for an integrated tool that can assist them in taking strategic decisions for managing and developing reliable, adequate and sustainable water distribution plans which provide the best services to farmers. Hence, four modules were integrated in DESIDS: (i) irrigation demand and scheduling module; (ii) hydraulic analysis module; (iii) operation and management module; and (iv) design and rehabilitation module. DESIDS was tested on different case studies, proving itself a valuable tool for irrigation district managers, as it provides a wide range of decision options for the proper operation and management of PIDSs. The developed DSS can be used as a platform for future integrations and expansions, and to include other processes needed for better decision-making support.
FeelMusic: Enriching Our Emotive Experience of Music through Audio-Tactile Mappings
Authors: Haynes Alice , Lawry Jonathan , Kent Christopher , Rossiter Jonathan
Published: June 2021

We present and evaluate the concept of FeelMusic and evaluate an implementation of it. It is an augmentation of music through the haptic translation of core musical elements. Music and touch are intrinsic modes of affective communication that are physically sensed. By projecting musical features such as rhythm and melody into the haptic domain, we can explore and enrich this embodied sensation; hence, we investigated audio-tactile mappings that successfully render emotive qualities. We began by investigating the affective qualities of vibrotactile stimuli through a psychophysical study with 20 participants using the circumplex model of affect. We found positive correlations between vibration frequency and arousal across participants, but correlations with valence were specific to the individual. We then developed novel FeelMusic mappings by translating key features of music samples and implementing them with “Pump-and-Vibe”, a wearable interface utilising fluidic actuation and vibration to generate dynamic haptic sensations. We conducted a preliminary investigation to evaluate the FeelMusic mappings by gathering 20 participants’ responses to the musical, tactile and combined stimuli, using valence ratings and descriptive words from Hevner’s adjective circle to measure affect. These mappings, and new tactile compositions, validated that FeelMusic interfaces have the potential to enrich musical experiences and be a means of affective communication in their own right. FeelMusic is a tangible realisation of the expression “feel the music”, enriching our musical experiences.
Oxido- and Dioxido-Vanadium(V) Complexes Supported on Carbon Materials: Reusable Catalysts for the Oxidation of Cyclohexane
Authors: Sutradhar Manas , Andrade Marta A. , Carabineiro Sónia A. C. , Martins Luísa M. D. R. S. , Guedes da Silva Maria de Fátima C. , Pombeiro Armando J. L.
Published: June 2021

Oxidovanadium(V) and dioxidovanadium(V) compounds, [VO(OEt)L] (1) and [Et3NH][VO2L] (2), were synthesized using an aroylhydrazone Schiff base (5-bromo-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (H2L). They were characterized by elemental analysis, Fourier-transform infrared spectroscopy (FT-IR), (1H and 51V) nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI-MS) and single crystal X-ray diffraction analyses. Both complexes were immobilized on functionalized carbon nanotubes and activated carbon. The catalytic performances of 1 and 2, homogenous and anchored on the supports, were evaluated for the first time towards the MW-assisted peroxidative oxidation (with tert-butylhydroperoxide, TBHP) of cyclohexane under heterogeneous conditions. The immobilization of 1 and 2 on functionalized carbon materials improved the efficiency of catalytic oxidation and allowed the catalyst recyclability with a well-preserved catalytic activity.
Magnetic Nanodiscs—A New Promising Tool for Microsurgery of Malignant Neoplasms
Authors: Zamay Tatiana N. , Prokopenko Vladimir S. , Zamay Sergey S. , Lukyanenko Kirill A. , Kolovskaya Olga S. , Orlov Vitaly A. , Zamay Galina S. , Galeev Rinat G. , Narodov Andrey A. , Kichkailo Anna S.
Published: June 2021

Magnetomechanical therapy is one of the most perspective directions in tumor microsurgery. According to the analysis of recent publications, it can be concluded that a nanoscalpel could become an instrument sufficient for cancer microsurgery. It should possess the following properties: (1) nano- or microsized; (2) affinity and specificity to the targets on tumor cells; (3) remote control. This nano- or microscalpel should include at least two components: (1) a physical nanostructure (particle, disc, plates) with the ability to transform the magnetic moment to mechanical torque; (2) a ligand—a molecule (antibody, aptamer, etc.) allowing the scalpel precisely target tumor cells. Literature analysis revealed that the most suitable nanoscalpel structures are anisotropic, magnetic micro- or nanodiscs with high-saturation magnetization and the absence of remanence, facilitating scalpel remote control via the magnetic field. Additionally, anisotropy enhances the transmigration of the discs to the tumor. To date, four types of magnetic microdiscs have been used for tumor destruction: synthetic antiferromagnetic P-SAF (perpendicular) and SAF (in-plane), vortex Py, and three-layer non-magnetic–ferromagnet–non-magnetic systems with flat quasi-dipole magnetic structures. In the current review, we discuss the biological effects of magnetic discs, the mechanisms of action, and the toxicity in alternating or rotating magnetic fields in vitro and in vivo. Based on the experimental data presented in the literature, we conclude that the targeted and remotely controlled magnetic field nanoscalpel is an effective and safe instrument for cancer therapy or theranostics.
Nanotechnological Applications Based on Bacterial Encapsulins
Authors: Rodríguez Javier M. , Allende-Ballestero Carolina , Cornelissen Jeroen J. L. M. , Castón José R.
Published: June 2021

Encapsulins are proteinaceous nanocontainers, constructed by a single species of shell protein that self-assemble into 20–40 nm icosahedral particles. Encapsulins are structurally similar to the capsids of viruses of the HK97-like lineage, to which they are evolutionarily related. Nearly all these nanocontainers encase a single oligomeric protein that defines the physiological role of the complex, although a few encapsulate several activities within a single particle. Encapsulins are abundant in bacteria and archaea, in which they participate in regulation of oxidative stress, detoxification, and homeostasis of key chemical elements. These nanocontainers are physically robust, contain numerous pores that permit metabolite flux through the shell, and are very tolerant of genetic manipulation. There are natural mechanisms for efficient functionalization of the outer and inner shell surfaces, and for the in vivo and in vitro internalization of heterologous proteins. These characteristics render encapsulin an excellent platform for the development of biotechnological applications. Here we provide an overview of current knowledge of encapsulin systems, summarize the remarkable toolbox developed by researchers in this field, and discuss recent advances in the biomedical and bioengineering applications of encapsulins.