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An industry compatible chemo-refining approach was tested for preparation of micro-nanofibrillated cellulose (MNFC) from bleached softwood pulp using sodium meta-periodate and sodium chlorite as oxidizers followed by refining in Valley beater. SEM and FTIR analyses confirmed micro-nano scale fibrillation and chemical functional group modification in laboratory prepared MNFC, respectively. The water retention value, carboxyl content and viscosity of MNFC were found comparable with imported NFC as reference (R-NFC). To evaluate MNFC as strength enhancer for paper properties, 5% MNFC addition to bleached mixed hardwood pulp showed 6% reduction in bulk with 36%, 24% and 97% increment in breaking length, burst index and double fold of the handsheets, respectively without affecting tear index and optical properties than the control. Surface properties were also improved. Pulp drainability (37°SR) after MNFC addition was found suitable for papermaking. These laboratory results confirmed the potential of MNFC as a suitable strength additive for paper quality improvement.

A superhydrophobic paper with excellent robustness was fabricated by roll coating with modified nano-TiO2. First, nano-TiO2 particles were hydrophobically modified by γ-aminopropyltriethoxysilane and 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (POTS). Then the paper coating composed of modified nano-TiO2 particles as pigments and epoxy resin (EP) as adhesives was coated on a paper surface to create the desired surface morphology and surface energy. Compared with the uncoated filter paper, the prepared paper showed an improved rough surface morphology owing to the uniform layer of TiO2 microclusters deposited on the fiber network. The superhydrophobic paper exhibited water contact angles (WCA) about 153° ± 1.5°, and water sliding angles (WSA) about 3.5° ± 0.5°, low surface adhesion and excellent bounce ability. The superhydrophobic paper can withstand a variety of wear and tear, such as tape stripping and knife scraping. The as-prepared superhydrophobic paper showed mechanical durability even after 20 wear cycles with sandpaper,thus sustaining excellent superhydrophobicity on the filter paper surface. Moreover, it remains fully functional even in environments with high concentrations of acid and alkali for 96 h. The superhydrophobicity was not affected after storage for 6 months in a natural environment. It was confirmed that the superhydrophobic paper surface exhibited excellent chemical stability, long-term stability and self-cleaning properties. The entire production process was operated under normal environment, without complex equipment; and, as such, has the possibility for large-scale production and application in industry.

The study describes the preparation of pulp and nanocellulose from non-wood plant materials, as well as an improved properties of paper and cardboard for mass production. The pulps from wheat straw, kenaf and flax fibers were prepared by the environmentally friendly organosolv method—cooking in a solution of isobutanol or peracetic acid. The organosolv pulps used to prepare nanocellulose had traces of lignin and mineral substances. The process of hydrolysis of the investigated organosolv pulps was optimal when carried out under the following conditions: 43% sulfuric acid, temperature 60 °C, hydrolysis time 90 min and ultrasonic treatment 60 min. Using the methods of SEM, XRD, TEM, AFM and TGA, the structure and properties of organosolv pulps and nanocellulose were studied. The use of nanocellulose in bulk and on the surface of mass types of paper and cardboard—paper for corrugation, offset paper, recycled containerboard and cardboard for flat layers of corrugated cardboard were investigated. We established the positive effect of nanocellulose application on the physical and mechanical properties of paper and cardboard. Low consumption of nanocellulose allows production of the paper and cardboard with properties that meet the requirements to appropriate standards and replacement of synthetic reinforcing materials.

Carbonization of biomasses is an effective and important approach to recycle biomass waste. The tissue papers are one of the most common household trash and waste lots of natural resources and energies. Herein, the one-step carbonization and activation treatment was applied on two kinds of tissue papers to transform them into porous carbons. It was found the precursor structure and composition as well as the calcination temperatures play key roles to control the pore structures. As the active materials of supercapacitor electrodes, the resultant porous carbons obtained from different paper precursors and calcination temperatures (700–900 °C) presented different electrochemical performances. The microporous carbons derived from the 700 °C calcination of the tissue paper using the wood pulp as the raw material showed high capacitance up to ~ 200 F/g, providing a simple but effective way to recycle biomasses.

Reduced graphene oxide (RGO) multilayer sheets were synthesized using waste paper pulp as carbon source. Formation of RGO was confirmed by Raman spectroscopy. RGO was mixed with cement at different concentrations (0.001, 0.01, 0.05 and 0.1% w/w) to obtain graphene cement composites (GCC). RGO is supposed to impart hydrophobicity to cement; hence, the capillary test was conducted. Hydrophobic property of GCC was found to be dependent on time, concentration and temperature. Antimicrobial property of GCC was checked which included antibacterial and antifungal studies. GCC showed better antibacterial performance (90%) against gram positive bacteria (Bacillus subtilis) than the gram-negative bacteria (Escherichia coli, 85%). Gram negative bacteria possess structurally more complex cell membranes than gram positive bacteria; hence, it was more resistant to GCC. Our finding supports the concept of involvement of membrane bound macromolecules in antibacterial performance of RGO. GCC was also found to be effective (88% inhibition) against fungal strain (Aspergillus niger).

The new analysis of the previously published data on the nanocrystalline CaYTiNbO7:Eu indicates an occurrence of the size-induced structural phase transition like in other nanocrystalline phosphors of pyrochlore structure.

Transition metal–based catalysts are considered to be promising materials to replace noble metal catalysts for electrocatalytic water splitting. Herein, a flexible electrode composed of Co-Ni-P ternary catalysts and carbon fiber paper substrate (Co-Ni-P/CFP) was successfully fabricated and applied in water electrolysis. The Co-Ni-P coatings were deposited on CFP by a one-step cyclic voltammetric electrodeposition method and the surface of the composite material exhibits nano-reticular structure. The formation mechanism was also discussed according to the results of material characterization. Notably, the Co-Ni-P/CFP flexible electrode exhibited superior catalytic performance for both hydrogen and oxygen evolution reactions in alkaline media, which could achieve 10 mA/cm2 current density with overpotential of 89 mV for HER and 320 mV for OER. Moreover, the Co-Ni-P/CFP electrode could also be used as both anode and cathode electrode to drive overall water splitting and required only 1.64 V to achieve a current density of 10 mA/cm2, which was very close to that of the commercial combination of Pt/C and IrO2. This affordable and easily obtained electrode offers a new avenue to develop earth-abundant resource catalysts for water electrolysis system.

A high quality graphene paper has been fabricated using drop-casting of a custom developed stable ink mixture. The graphene/ethyl cellulose mixture can produce graphene paper coating on Kapton substrate at fairly large scales by finely adjusting the viscosity of the ethyl cellulose solvent blend. It was possible to produce a morphologically intact 300 nm-thick stacked structures of high purity graphene platelets after annealing at 300 °C, as characterized by SEM, Raman Spectroscopy and AFM. The electrical resistivity of a large batch of samples was measured and the results thoroughly evaluated, using a design of experiments approach. The resistivity values achieved were found to be lower or comparable to the best results reported in the literature. As expected, resistivity is inherently related to the concentration of the as-prepared ink and subsequent annealing conditions. However, prolonged annealing time can deteriorate mechanical properties as determined by cyclic bending and shear tests. It is anticipated that the present graphene paper has potential use in flexible electronics applications since the lowest resistivity and structure achieved were generally unaffected by the range of mechanical loadings studied.

We synthesized a flexible lithium-ion battery (LIB) anode with a flower-like CuCo2O4 nanostructure grown on the surface of conductively-treated filter paper. The filter paper, made of cotton fibers, has good flexibility, but its poor conductivity limits its application in flexible electrodes. An Ni coating by magnetron sputtering can significantly improve its conductivity, which enables it to be used as a substrate for flexible electrodes. The flower-like CuCo2O4 nanostructure is assembled from CuCo2O4 nanowires with a diameter of 50 nm, while the CuCo2O4 nanowires are assembled from CuCo2O4 nanoparticles with a size of 10–20 nm. The gap between the stacked CuCo2O4 nanoparticles causes the porous structure of the CuCo2O4 nanowires. The high theoretical capacity of CuCo2O4, the porous structure of the CuCo2O4 nanowires, and the tiny CuCo2O4 nanoparticles lead to the excellent electrochemical performance of the CuCo2O4 flower-like nanostructure. It maintains capacity very well during cycling and delivers a high capacity of 989 mAh g−1 at a current density of 100 mA g−1. As a flexible LIB anode, the composite with the flower-like CuCo2O4 nanostructure grown on the surface of conductively-treated filter paper delivers a stable capacity of 544 mAh g−1 at a current density of 100 mA g−1 and a capacity of 304 mAh g−1 at a high current density of 2000 mA g−1. The conductively-treated filter paper substrate can significantly improve the battery property of the hydrothermally-fabricated CuCo2O4.

Recently perovskite solar cells (PSCs), as photoelectric conversion devices, exhibit excellent power conversion efficiency (PCE) and low-processing cost, and have become one of the most promising devices to replace conventional silicon-based solar cells and address current pressing energy issues. Among them, the flexible PSCs are especially more widely applicable and may propel the rapid advancements of wearable electronics, causing a significant paradigm shift in consumer electronics. Current flexible PSCs use non-biodegradable petroleum-based polymer substrates, discarding of which will aggravate “white pollution”. Therefore, development of green, biodegradable and low-cost flexible substrates will provide a great alternative to flexible PSCs. Here we have developed transparent nanocellulose paper (NCP) with coating of acrylic resin as substrates to fabricate flexible PSCs, which are biodegradable and easily disposable. The PCE of these NCP-based PSCs reached 4.25%, while the power per weight (the ratio of power to device weight) was as high as 0.56 W g–1. The flexible PSCs also showed good stability, retaining >80% of original efficiency after 50 times of bending. The NCP-based substrates can also be applied to other electronic systems, which may prosper next-generation green flexible electronics. Modified nanocellulose paper has been shown to be excellent biodegradable substrate for flexible perovskite solar cells and potentially other green flexible devices. A team of Chinese scientists led by Prof Wei Huang from Institute of Advanced Materials, Nanjing Tech University fabricate flexible perovskite solar cells on transparent nanocellulose paper. This becomes feasible only after they develop a treatment recipe to improve the mechanical, optical properties and the waterproof ability of the pure nanocellulose paper. The flexible solar cells on the modified substrates show high specific power of 0.56 W g-1 and good stability and mechanical durability. Another key advantage of nanocellulose paper is its biodegradation capability, making it a better substrate compared to PEN and PET for the next generation green flexible electronics.

Dynamic logic style is used in high performance circuit design because of its fast speed and less transistors requirement as compared to CMOS logic style. But it is not widely accepted for all types of circuit implementations due to its less noise tolerance and charge sharing problems. A small noise at the input of the dynamic logic can change the desired output. Domino logic uses one static CMOS inverter at the output of dynamic node which is more noise immune and consuming very less power as compared to other proposed circuit. In this paper, an overview and classification of these techniques are first presented and then compared according to their performance.

Misalignment of mechanical rolling elements such as belt and pulley causes catastrophic malfunctions of high speed paper feeding systems like automated teller machines (ATMs), printers, and copy machines. A combination of a crown pulley and a belt can be an effective self-alignment mechanism for the systems. In this paper, an equation of motion of the belt and pulley system is driven, verification tests are carried out, and a design improvement strategy is suggested for high speed paper media transport systems.

The industrial sector of flexible printed electronics has shown a dynamic growth in the last decades. Therefore, demand for new inks, coatings and printing methods leading to improved performances of the electronic components at room temperature is also increasing. Here, we present a study on the conductive properties of silver layers obtained by different coating and printing methods. The results obtained proved that drop-on-demand inkjet printing of water-based inks containing micron-sized silver flakes with narrow-size distribution is a feasible method for in situ fabrication of conductive silver coatings that does not require additional heat treatment. A rigorous optimization Taguchi experiment was carried out considering the major process parameters. This experiment showed that the printing pressure was the dominant factor defining the quality of the printed coatings and tracks.

Today's economical cycles challenge the test program generation process for semiconductors with regard to productivity, time-to-market, increasing quality requirements and manufacturing robustness, while, at the same time, the complexity of the system-on-a-chip mixed-signal integrated circuits to be tested increases significantly. Furthermore, commercial challenges in combination with competitive advantage become an important factor, not only within semiconductor manufacturing, but also within test program development. This paper provides a review of these challenges, and how they might be addressed. We first give a short introduction and background on semiconductor testing and test development with the focus on mixed-signal and systems-on-chip. This is followed by current roadmaps and considerations for test program software development. Based on the highlighted strength and weaknesses of the reviewed approaches, the authors conclude with some recommendations to address these challenges by adopting software engineering methods for the test program development process.

A web is continuous, flexible materials such as paper, plastic film, metal foil, textiles, etc. Web wrinkle is a problem which plagues the process industries. Most webs are very thin and prone to buckle or wrinkle. The effects of wrinkling can range from compromised product quality to down time of a processing operation, leading to less profitability in the manufacturing operation. The web wrinkles which will be treated in this paper are those that can be affected by roller misalignment and friction characteristics between web and roller. In this paper, observation method is presented for paper-web wrinkling and the prediction model of wrinkling is proposed with experimental verifications.

A skew of a paper transferred by rubber rollers in printers is simulated by FEM software. Effects of an imbalance of preload, an imbalance distribution of coefficient of friction and a front tension on the paper skew are investigated and how to determine the skew direction are shown. A simulation model is composed of a feed roller, a preload roller and a paper. The feed roller is rotated forcibly by a certain degree at every calculation step and a deformation, displacement and strain of the paper and rollers are calculated. A series of calculation results is shown as a motion simulation. The results show that the paper skews to the smaller preload side, to the smaller coefficient of friction side, or to the opposite side of the front tension. Further, effects of a skew prevention guide plate is simulated.

An efficient mechanism that uses a heat roller and a pressure roller for flattening crumpled paper was developed. The mechanical properties of creased paper bills that had been exposed to tension and a heated hot-air stream were measured, and the folds in the paper bills were observed optically by laser microscope. It was found that before flattening, the fibers in the folded papers bills showed kinks. After flattening, however, the kinks remained. It was also found that applying heat strengthened the paper. Based on these results, a mechanical model for flattening crumpled paper bills was devised and tested. The numerical results of the mechanical model for flattening paper agreed well with the experimental ones. It was found that the calculated paper height from the mechanical model agrees well with the experimentally measured height, and this agreement confirms the applicability of the model.

A paper transport mechanism that generates tractive force in the cross direction perpendicular to the paper transport direction was developed. The mechanics of this mechanism were then investigated by using the finite element method (FEM). A pair of tapered rubber rollers is the key point of the mechanism. Each roller has two tapered surfaces that thin out in the same direction. The thin sides of both tapered rollers face each other symmetrically to form the center of the transport mechanism. A cylindrical steel roller is pressed toward the tapered roller by a spring. Paper sheets are nipped between the tapered rubber roller and the cylindrical steel roller. On being pressed, the tapered roller is bent around the mid point of the side of the roller because of it has an asymmetrical cross section. The bend first produces shear stress on the contacting area perpendicular to the transport direction. Second, it produces a bulgy deformation so the roller shape is pressed out in the same direction. These processes generate tractive force on the paper. However, the tapered roller generates not only a tractive force but also a twisting moment. Therefore, one roller has two tapered surfaces to cancel the twisting moment. FEM analysis indicates that the tractive force could be estimated within 20% error in comparison with the measured value. The advantages of the new mechanism are that rubber rollers are used in almost all paper-handling equipment and simply cutting two tapers can generate tractive force. This mechanism improves transport reliability preventing wrinkles and slack.

Reducing the amount of industrial crop waste and converting it into high value-added products in a sustainable manner will not only promote the use of biological resources but will also help in reducing the environmental impact. Bast fibers of Kozo (Broussonetia kazinoki) are a raw material of traditional Japanese paper, known as “Washi.” However, the wood part of this plant is not used for Washi and is discarded. The aim of this study was to find a new future use for the wood parts of the plant. The first step was to confirm whether the wooden part of Kozo could be converted into cellulose nanofibers (CNFs). CNFs made from bast fiber alone and from bast fiber that included the outer bark were prepared as samples for comparison. Subsequently, the morphological and chemical structures of the raw materials, wood powder, pulp, and CNFs from each sample were analyzed. Consequently, we found that CNFs made from wooden parts have a chemical structure similar to that of the bast fiber, which is the raw material of Washi; however, it is the thinnest CNF of all those investigated. In addition, the CNF solution prepared from wooden parts adjusted to a 0.5-wt% concentration showed the highest viscosity characteristics and also the highest adhesive strength when applied to Japanese paper. These results indicate that waste wood parts have potential applications as chemical-free thickeners, adhesives, and restorative materials.

While the focus of our preceding investigations, presented on the last HARMST 2001 in Baden Baden, was the miniaturization of fuel cells in order to increase their power density, the current activities at the IMTEK concentrate on the identification of processes that have the potential to lower the production costs of those miniaturised fuel cells. As a novel approach, we replaced the commonly used backing layer and flow fields made from graphite or steel by a flow field with micro channels structured in carbon paper. A micrograph of these structures is shown in Figure 1. For the first time, such structures were produced using Wire Electro Discharge Machining (WEDM). With our proven cell setup [1], we reach energy densities comparable to the system we presented at the last HARMST 2001, while being able to produce the cells at considerably lower costs. Another major advantage of the use of graphitic materials is that the cell is no longer prone to corrosion.

The linearisation procedure used in the modelling of the hydro-pneumatic suspension system by Moreau et al. contains an inaccuracy. Hence, the conclusion that the weight of the sprung mass is normally absent of the dynamic behaviour of the sprung mass is demonstrated to be false.

The main purpose of this study is to optimize the applicability of TiO2 nanoparticles for paper mill and pulp wastewater treatment under solar irradiation using response surface methodology, provided by the software package DOE. The principle independent parameters were TiO2 loading, pH, time and H2O2 concentration, and COD removal efficiency was chosen as desire response. To evaluate the influence of the parameters on the outputs, the quadratic formulation was applied and for determining the validation of developed models analysis of variance was utilized. The results represented the greatest COD removal was achieved 82%, approximately at pH of 8.1, TiO2 fraction of 0.83 g/L, H2O2 concentration of 2.4 ml/L and the contact time of 196 min.

Waste materials utilization as value-added materials and micro, nanoparticles inclusion is gaining huge attention. The sludge generated from the textile industry constitutes a high toxic compound and hazardous in nature. Currently, large quantities of solid sludge remain unattended and undisposed in various effluent plants, waiting to be disposed of at the landfills. In this study, the waste sludge generated from the textile industry was processed and reused as a substitute for cement material. The specimens prepared from the textile waste sludge along with nanoparticles were tested for durability and mechanical properties. The usage of textile sludge decreases the strength properties marginally until a replacement level of 10%. Beyond the addition of 10% textile sludge waste reduces the strength and durability properties significantly. Textile waste sludges were replaced for cement of varying proportions, i.e., 2.5%, 5%, 7.5%, 10%, 15% and 20%. The addition of alumina nanoparticles has dual effects, enhances the hydration properties and also acts as a filler material. The formation of calcium silicate hydrate gel was improved significantly due to the utilization of nano alumina. The optimum amount of alumina nanoparticles observed from the previous studies was found to be 3% by weight of cement due to high durability and mechanical properties. The combination of 10% textile waste sludge along with 3% nano alumina blended cement concrete leads to enhanced strength and durability characteristics as compared to all other concrete specimens and it was found to better eco-friendly construction material.

In this paper, a generalized fractional-order SEIR model is proposed, denoted by SEIQRP model, which divided the population into susceptible, exposed, infectious, quarantined, recovered and insusceptible individuals and has a basic guiding significance for the prediction of the possible outbreak of infectious diseases like the coronavirus disease in 2019 (COVID-19) and other insect diseases in the future. Firstly, some qualitative properties of the model are analyzed. The basic reproduction number \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{ R }}_{0}$$\end{document}R0 is derived. When \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{ R }}_{0}1$$\end{document}R0>1, the endemic equilibrium point is also unique. Furthermore, some conditions are established to ensure the local asymptotic stability of disease-free and endemic equilibrium points. The trend of COVID-19 spread in the USA is predicted. Considering the influence of the individual behavior and government mitigation measurement, a modified SEIQRP model is proposed, defined as SEIQRPD model, which is divided the population into susceptible, exposed, infectious, quarantined, recovered, insusceptible and dead individuals. According to the real data of the USA, it is found that our improved model has a better prediction ability for the epidemic trend in the next two weeks. Hence, the epidemic trend of the USA in the next two weeks is investigated, and the peak of isolated cases is predicted. The modified SEIQRP model successfully capture the development process of COVID-19, which provides an important reference for understanding the trend of the outbreak.

Now a days, phytochemical screening and GCMS analysis draw the attention of researchers, as it is the important tool to analyze secondary metabolites and bioactive compounds which are used to produce the herbal medicines, food colorants, flavors and fragrances. In this study bioactive compounds and phytochemical constituents of Jumbo muscadine grape pulp extract are analyzed. The extract has been characterized by UV and FTIR in which both the optical property and functional groups are identified. Absorption spectra of UV showed the highest peak at 270 nm which associates to the polyphenol and functional groups such as alcohol; alkene has been interpreted using FTIR spectrum. Presence of phytochemicals is confirmed by qualitative tests and quantified. Bioactive compounds are interpreted using gas chromatography–mass spectrometry analysis. This grape extract contains phenols, terpenoids, saponins and carbohydrates as major phytochemicals. Identified essential bioactive compounds of this extract include Glycerin, oleic acid, palmitic acid and 5-hydroxymethyl furfural.

Renewable plant materials are of interest for the development of new biodegradable materials. The study describes the preparation process of nanocellulose from organosolv reed pulp (ORP). ORP was obtained from reed stalks in two stages: by extraction of the raw material with NaOH solution and cooking using a mixture of acetic acid and hydrogen peroxide. Nanocellulose was extracted from ORP using 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) in a TEMPO/NaBr/NaClO system followed by ultrasonic treatment to obtain a stable nanocellulose gel. It was found that an increase in the TEMPO consumption and oxidation time increases the density and tensile strength, the content of carboxyl groups, and the transparency of the nanocellulose films, but decreases the yield and crystallinity of the nanocellulose. Structural and chemical changes and the crystallinity index of reed stalks, ORP, and nanocellulose were studied using SEM, FTIR, and XRD methods. Nanocellulose films had a density of up to 1.51 g/cm3, a transparency of up to 82.4%, a carboxyl group content of up to 1.18 mmol/g, and a tensile strength of up to 69.7 MPa. The crystallinity index of nanocellulose decreases from 78.8 to 64.9% with an increase in the oxidation time. TEM and AFM methods have shown that the width of nanocellulose particles is from 3 to 20 nm. TGA confirmed a decrease in the crystallinity index of nanocellulose as a result of its prolonged oxidation. The properties of the obtained nanocellulose from ORP demonstrate the great potential of its application for the preparation of new nanocomposite materials.

A personal mini-review is presented on the history of electroanalysis and on their present achievements and future challenges. The manuscript is written from the subjective view of two generations of electroanalytical chemists that have witnessed for many years the evolution of this discipline.

The core–shell carbon microspheres (Fe2O3@CM) were prepared from iron chloride (FeCl3) and cotton pulp fibers by hydrothermal carbonization method. The carbonized fibers are intertwined and gradually covered on the surface of Fe2O3 nanoparticles. Herein, Fe2O3 nanoparticles as cores can increase the electrical conductivity and reactive sites, the porous and functional carbonized fibers as shells are favourable for the improvement of structure stability. The optimal Fe2O3@CM-2 samples were used as supercapacitor electrodes. A considerable specific capacitance of 282.8 F/g was thus achieved. Simultaneously, the excellent cycling stability of 97.5% was obtained. This study broadens high-valued utilization of cellulose and provides new ideas for the development of renewable and environment-friendly flexible energy storage devices.

The cyclic nature of the stick-slip phenomenon may cause catastrophic failures in drill-strings or at the very least could lead to the wear of expensive equipment. Therefore, it is important to study the drilling parameters which can lead to stick-slip, in order to develop appropriate control methods for suppression. This paper studies the stick-slip oscillations encountered in drill-strings from both numerical and experimental points of view. The numerical part is carried out based on path-following methods for non-smooth dynamical systems, with a special focus on the multistability in drill-strings. Our analysis shows that, under a certain parameter window, the multistability can be used to steer the response of the drill-strings from a sticking equilibrium or stick-slip oscillation to an equilibrium with constant drill-bit rotation. In addition, a small-scale downhole drilling rig was implemented to conduct a parametric study of the stick-slip phenomenon. The parametric study involves the use of two flexible shafts with varying mechanical properties to observe the effects that would have on stick-slip during operation. Our experimental results demonstrate that varying some of the mechanical properties of the drill-string could in fact control the nature of stick-slip oscillations.

The new generations of compact high output power-to-weight ratio internal combustion engines generate broadband torsional oscillations, transmitted to lightly damped drivetrain systems. A novel approach to mitigate these untoward vibrations can be the use of nonlinear absorbers. These act as Nonlinear Energy Sinks (NESs). The NES is coupled to the primary (drivetrain) structure, inducing passive irreversible targeted energy transfer (TET) from the drivetrain system to the NES. During this process, the vibration energy is directed from the lower-frequency modes of the structure to the higher ones. Thereafter, vibrations can be either dissipated through structural damping or consumed by the NES. This paper uses a lumped parameter model of an automotive driveline to simulate the effect of TET and the assumed modal energy redistribution. Significant redistribution of vibratory energy is observed through TET. Furthermore, the integrated optimization process highlights the most effective configuration and parametric evaluation for use of NES.

Hydro-alcoholic (2:8 v/v) extract of the pulp of Phoenix dactylifera fruit pulp obtained using Soxhlet extraction (70 °C, 6 h) was found to contain alkaloids, sterols, tannins, flavonoids, cardiac glycosides, proteins, and carbohydrates. An aqueous solution (20% v/v) of the extract led to the synthesis of silver nanoparticles (AgNPs) from 0.01 M AgNO3 solution as confirmed by the surface plasmon resonance at 445 nm determined using UV–visible spectroscopy after 24 h. The synthesized AgNPs were found to be mostly spherical and complexed with phytochemicals from the extract. The size of AgNPs ranged from 12.2–140.2 nm with mean diameter of 47.0 nm as characterized by scanning electron microscopy (SEM). The elemental composition of the AgNPs complexed with the phytochemicals was found to be 80.49% silver (Ag), 15.21% carbon (C), and 4.30% oxygen (O) on a weight basis by energy-dispersive spectroscopy (EDS). Using the α,α-diphenyl-β-picrylhydrazyl (DPPH) assay, an anti-oxidant activity of 89.15% for 1 µg L−1 ultrasonically homogenized ethanolic solution of complexed AgNPs was obtained (equivalent to 0.20 mg mL−1 gallic acid solution), while methanolic solution of plant extract possessed an EC50 value of 3.45% (v/v) (equivalent to 0.11 mg mL−1 gallic acid solution). The plant-nanosilver broth was also found to possess effective anti-microbial activity against Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, and Candida albicans ATCC 10231 as assessed by the disc diffusion assay. However, the plant extract showed negligible anti-microbial activity.

This paper reviews recent advances in fully printed chipless radio frequency identification (RFID) technology with special concern on the discussion of coding theories, ID generating circuits, and tag antennas. Two types of chipless tags, one based on time-domain reflections and the other based on frequency domain signatures, are introduced. To enable a fully printed encoding circuit, linearly tapering technique is adopted in the first type of tags to cope with parasitic resistances of printed conductors. Both simulation and measurement efforts are made to verify the feasibility of the eight-bit fully printed paper-based tag. In the second type of tags, a group of LC tanks are exploited for encoding data in frequency domain with their resonances. The field measurements of the proof-of-concept of the tag produced by toner-transferring process and flexible printed circuit boards are provided to validate the practicability of the reconfigurable ten-bit chipless RFID tag. Furthermore, a novel RFID tag antenna design adopting linearly tapering technique is introduced. It shows 40 % save of conductive ink materials while keeping the same performance for conventional half-wave dipole antennas and meander line antennas. Finally, the paper discusses the future trends of chipless RFID tags in terms of fabrication cost, coding capacity, size, and reconfigurability. We see that, coupled with revolutionary design of low-cost tag antennas, fabrication/reconfiguration by printing techniques, moving to higher frequencies to shrink tag sizes and reduce manufacturing cost, as well as innovation in ID generating circuits to increase coding capacities, will be important research topics towards item-level tracking applications of chipless RFID tags. QC 20130823

In this research reduced graphene oxide (rGO) was synthesized by reduction of graphene oxide (GO) with N,N diethylhydroxylamine as a reductant. The GO and RGO was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy and atomic force microscopy. Results showed GO was reduced to few-layers level with poor dispersion in water. The composite coating of Ni–Zn–rGO and Zn–Ni–GO on copper plate was obtained by the electrodeposition technique. The composite films were studied by XRD and SEM. The composites coating was subjected to various electrochemical tests such as The electrochemical impedance spectroscopy, taffel plot and Vickers micro hardness to know theirs corrosion behavior and compared with Ni–Zn coating. The results confirmed the addition GO and rGO enrichment corrosion resistance property very much compare to Zn–Ni alloy.

Silver nanoparticles were synthesized on bamboo pulp fabric with pretreatment of plasma under microwave radiation. The silver nanoparticles coated bamboo pulp fabrics were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, thermogravimetric analysis and X-ray diffraction. Color characteristics and contact angles of silver coated bamboo pulp fabrics were evaluated. Adhesive strength of silver nanoparticles on bamboo pulp fabrics without and with pretreatment of plasma was investigated. Compared with silver nanoparticles coated bamboo pulp fabric without pretreatment of plasma, more silver nanoparticles are coated on the bamboo pulp fabric with pretreatment of plasma. Bamboo pulp fabrics are evenly covered with silver nanoparticles with pretreatment of plasma. In addition, influences of distance between the plasma source and the fabric and treating time on deposition amounts of silver nanoparticles were investigated. Color strength values decrease and increase with the rise of distance and treatment time, respectively. The silver nanoparticles coated bamboo pulp fabric pretreatment of plasma has excellent UV protection, good fastness to laundering and hydrophobicity.

Cobalt oxide (Co3O4)–graphene nanosheets (GNS) composite was prepared using a novel route. Room temperature prepared graphite oxide was exfoliated at low temperature and subsequently reduced to GNS by chemical method. Successful compound formation was confirmed and structural details were obtained from XRD studies. Cobalt oxide was found to crystallize in spinel fcc structure with average crystallite size of 9 nm in the composite. FTIR and XPS study confirms the removal of oxygen containing functional group in reduced graphene and spinel formation of cobalt oxide in the composite. Raman spectra depict the reestablishment of sp2 conjugated network of carbon atoms, on reduction to graphene. FESEM images reveal the nanosheet like morphology of the graphene being retained in the composite and promoting ion diffusion channels. Electrochemical characterization discloses the pseudocapacitive behaviour of the composite material. Higher specific capacitance of 650 F/g was exhibited by GNS–Co3O4 at 5 mV/s scan rate. Symmetrical supercapacitor fabricated using GNS–Co3O4 demonstrated superior power characteristics. Graphene in the composite has substantially increased the electron and ion transport in the electrode material leading to enhanced performance.

This paper describes the theoretical modeling for the prediction of slippage onset condition between the paper web and steel roller with experimental verifications. For the first step of modeling, the occurrence of slippage is observed for the cases of uncoated paper (newsprint) and coated paper, and the relation between the slip ratio and roller velocity is measured by changing web tension. Two kinds of theoretical model are proposed, and the applicability of the models is confirmed experimentally.

In order to bring graphene materials much closer to real world applications, it is imperative to have simple, efficient and eco-friendly ways to produce processable graphene derivatives. In this study, a hydrophilic low-temperature thermally functionalized graphene and its super-hydrophobic organically modified graphene derivative were fabricated. A unique structural topology was found and some of the oxygen functionalities were retained on the thermally functionalized graphene surfaces, which facilitated the subsequent highly effective organic modification reaction and led to the super-hydrophobic organically modified graphene with multifunctional applications in liquid marbles and polymer nanocomposites. The organic modification reaction also restored the graphenic conjugated structure of the thermally functionalized graphene, particularly for organic modifiers having longer alkyl chains, as confirmed by various characterization techniques such as electrical conductivity measurements, ultraviolet/visible spectroscopy and selected area electron diffraction. The free-standing soft liquid marble was fabricated by wrapping a water droplet with the super-hydrophobic organically modified graphene, and showed potential for use as a microreactor. As for the polymer nanocomposites, a strong interfacial adhesion is believed to exist between an organic polymer matrix and the modified graphene because of the organophilic coating formed on the graphene base, which resulted in large improvements in the thermal and mechanical properties of the polymer nanocomposites with the modified graphene, even at very low loading levels. A new avenue has therefore been opened up for large-scale production of processable graphene derivatives with various practicable applications.

Noble metals such as Pt are a perfect substrate for the catalytic growth of monolayer graphene. However, the requirements of the subsequent transfer process are not compatible with the traditional etching method. In this work, we find that the interaction of graphene with Pt foil can be weakened through the intercalation of carbon monoxide (CO) under ambient pressure. This intercalation process occurs on both hexagonal-shape graphene islands and irregular graphene patches on changing the CO partial pressure from 0 to 0.6 MPa, as observed by scanning electron microscopy (SEM), Raman spectroscopy and X-ray photoemission spectroscopy. We demonstrate that, on a practical timescale, the intercalation ratio is proportional to the partial pressure of CO. Furthermore, we develop a clean transfer method of CO-intercalated graphene with water as a peeling agent. We show that this method enables the transfer of tens of micrometer-scale graphene patches onto SiO2/Si, which are free from metal or oxide particle contamination. This transfer method should be a significant step towards the clean transfer of graphene, as well as the recyclable use of noble metal substrates.

We present a network framework for evaluating the theoretical performance limits of wireless data communication. We address the problem of providing the best possible service to new users joining the system without affecting existing users. Since, interference-wise, new users are required to be invisible to existing users, the network is dubbed PhantomNet. The novelty is the generality obtained in this context. Namely, we can deal with multiple users, multiple antennas, and multiple cells on both the uplink and the downlink. The solution for the uplink is effectively the same as for a single cell system since all the base stations (BSs) simply amount to one composite BS with centralized processing. The optimum strategy, following directly from known results, is successive decoding (SD), where the new user is decoded before the existing users so that the new users' signal can be subtracted out to meet its invisibility requirement. Only the BS needs to modify its decoding scheme in the handling of new users, since existing users continue to transmit their data exactly as they did before the new arrivals. The downlink, even with the BSs operating as one composite BS, is more problematic. With multiple antennas at each BS site, the optimal coding scheme and the capacity region for this channel are unsolved problems. SD and dirty paper (DP) are two schemes previously reported to achieve capacity in special cases. For PhantomNet, we show that DP coding at the BS is equal to or better than SD. The new user is encoded before the existing users so that the interference caused by his signal to existing users is known to the transmitter. Thus the BS modifies its encoding scheme to accommodate new users so that existing users continue to operate as before: they achieve the same rates as before and they decode their signal in precisely the same way as before. The solutions for the uplink and the downlink are particularly interesting in the way they exhibit a remarkable simplicity and an unmistakable, near-perfect, up-down symmetry.

We are pleased to host the 20th ISPS conference and serve as the editors for this Special Issue. This Special Issue is a collection of peer-reviewed, journal quality papers contributed by authors from the 20th ASME Annual Conference on Information Storage and Processing Systems (ISPS) held in Santa Clara University, Santa Clara, California, USA on June 14 and 15, 2010. As the milestone to archive outstanding research and development work presented in the 20th ISPS conference, all authors of papers accepted by the conference were encouraged and invited to submit full paper to this Special Issue in Springer Journal of Microsystem Technologies. Manuscripts submitted to this Special Issue were rigorously reviewed by experts and researchers form universities and industry research and development centers. Out of 117 conference papers presented at the 20th ISPS conference, 85 invitations were made and 75 were submitted to this Special Issue for review. Through the peer-review process, 14 were rejected. Before being accepted and published in this Special Issue, many of the 61 contributions had to be revised substantially. Without doubts, papers published in this Special Issue are special collections of many technical topics presented at the 20th ISPS conference. The 20th ASME ISPS conference is a very unique international conference that brings together academia and industry in joint sessions on research topics that are of interdisciplinary nature. Papers included in this Special Issues were contributed by authors who presented their latest research and development work in following technical sessions at the 20th ISPS conference

Cyber-Physical Production Systems (CPPS) form the basis of the next industrial revolution. However, many manufacturing companies are reluctant to adopt this disruptive technology due to a lack of know-how and a high project risk. In this paper, we present the development of a design tool that addresses common challenges of CPPS engineering, including the complexity of CPPS and the collaborative, multidisciplinary nature of the engineering process. The tool is based on the combination of existing and emerging reference models, standards and methods from software engineering, production automation and Industry 4.0, embedded in a new model of collaborative engineering for CPPS. The paper describes the foundational concepts of the tool, highlights its innovations, and reports some of the insights gained during its development and its usage in an industrial scenario.

Rolling stock connection systems are key to running longer and heavier trains as they provide both the connections of vehicles and the damping, providing the longitudinal suspension of the train. This paper focuses on the evolution of both connection and stiffness damping systems. Focus is on freight rolling stock, but passenger draw gears are also examined. It was found that connection systems have evolved from the buff and chain system used in the pioneer railways of the 1800s to the modern auto-coupler connection systems that are in-service worldwide today. Refined versions of the buff and chain coupling are, however, still in use in the EU, UK, South America and India. A wide range of auto-coupler systems are currently utilised, but the AAR coupler (Janney coupler) remains the most popular. A further variation that persists is the SA3 coupler (improved Wilson coupler) which is an alternative auto-coupler design used mainly throughout the former Soviet Union. Restricting the review to auto-coupler systems allowed the paper to focus on draft gears which revealed polymer, polymer-friction, steel spring-friction, hydraulic draft gears and sliding sill cushioning systems. Along with the single compressive draft gear units balanced and floating plate configurations are also presented. Typical draft gear acceptance standards are presented along with modelling that was included to aid in presentation of the functional characteristics of draft gears.

This paper presents a simplified method of system stability improvement and cost-effective solution by accelerated distance protection using direct fiber optic signal between the (end-to-end) relays. Transmission line protection is one of the important priority of protection, as their correct and selective tripping and fast fault clearance will avoid instability in the grid, which otherwise may result in cascade tripping leading to instability of the grid. This paper proposes a new approach by using optical ground wire (OPGW) direct relay-to-relay teleportation in association with modern numerical distance relay for accelerated distance protection, instead of carrier aided power line communication protection scheme. This methodology enhances the tripping function faster. Thus, quick isolation of the fault improves the stability of the grid. In this new technique, there is significant reduction in circuit complexity which reduces in cost for PLCC equipments and scheme and also saving the control room area.

Electromagnetic (EM) absorbers are becoming an important tool in the recent advanced technologies as well as for environments to minimize the level of microwave radiations in specific structures or places. Indeed, they are employed in radar absorbing materials (RAMs) and in defense, communication electronics, medical equipment, human health care, laboratory environments and public safety issues. In strategic areas, where the electromagnetic interference (EMI) shielding effectiveness is essential, the components and parts made by EMI shielding materials is to be upgraded. The EM shield play a significant role in reducing the intensity of reflected and transmitted EM waves. Recently, research on EM wave absorbers is focused on polymer-based structures, and layered carbon structures. The basic qualities of polymer and carbon have been successfully applied to minimize the reflection coefficient, and maximize absorption coefficient in metrology as well as in defense equipment’s. In this context, most of the studies use composites made with polymers and carbon materials and some studies are focused on foamed structures and metamaterials. In the present work, polyaniline (PANI) and carbon fiber (CF)-based paper like sheet structures were produced by compression molding technique and their electrical and EMI shielding properties are measured in X-band (8.2–12.4 GHz) frequency range. PANI paper has been found to have an electrical conductivity of 12.48 S/cm and EMI shielding effectiveness of PANI paper is found to be − 26.82 dB at a thickness of 0.75 mm. Scanning electron microscopy (SEM) approves the coating of polymer on carbon fiber and thermogravimetric analysis (TGA) demonstrates that the presence of carbon fiber drastically improves the thermal stability of the polymer sheets .

In this paper, we present the development and performance analysis of AlNB alloy for thermal management applications. The AlNB alloy at nanoscale film thickness is grown in stack configuration of (Al-AlN-B) on modified aluminium (Al) substrates (5052) using reactive sputtering at room temperature and annealed at 400 °C under nitrogen ambient. Cubic aluminium nitride (c-AlN) structures with (200) and (220) orientations are confirmed by the X-ray diffractometer (XRD) analysis. Furthermore, the presence of AlN and boron nitride (BN) is established from Fourier-transform infrared spectroscopy (FTIR) spectra. The measured film thickness of the AlNB alloy films is in the range from ~ 157.4 to 378.8 nm, while the particle sizes are in the range between ∼80 and 300 nm. The measured roughness of the films is in the range ~ 54 and 82 nm for the three samples, by the processing of Atomic Force Microscopy (AFM) images using Nanoscope software. However, from the cumulative structure function analysis, the total thermal resistance of the light-emitting diode (LED) (Rthj-a) is reduced by about ~ 4 to ~ 23%, with samples 1 (AlN/B), 2 (AlN/B/AlN/B) and 3 (AlN/B/AlN/B/AlN) as compared to that of bare Al substrate. Previous literature on similar material indicates higher thermal resistance of about 43–53 (K/W); however, in our work, we were able to achieve low Rth of 8.5 (K/W) as reported in this paper. Furthermore, considering the structural properties, surface, and good thermal performance coupled with lower bond line thickness (BLT) in ~ 150 nm range exhibited by the grown alloy, the developed material is therefore recommended for effective thermal management application of LEDs and other solid-state devices at low and high operational current densities.

Vanadium dioxide (VO2) will undergo a reversible phase transition when under thermal, electrical or optical stimuli. The use of electric field to induce the transport properties is promising for novel switches, volatile memory and photodetectors. In this paper, VO2 nanoparticles were synthesized by the hydrothermal and post-vacuum annealing method. And then, the electro-induced MIT of the composite film filled with VO2 particles was discussed. The results show that purity VO2 (B) with different morphologies were obtained at different temperatures from 120 to 240 °C. The HRTEM images proved that the VO2 (B) nanobelts grow in the direction of the (110) plane, and the VO2 (M) nanoparticles grow along the (110) crystal plane. SEM pictures illustrate that the length of the nanoparticles becomes smaller as the preparation temperature increases. DSC reports and I-V traces proved that the VO2 (M) has an excellent performance of phase transition under heating and voltage. The results show that the hydrothermal temperature is helpful to increase the initial resistance, resistance change rate and phase change voltage of VO2 composite film. And the maximum resistance change rate before and after the MIT of samples is higher than 200. The experimental results show that the VO2 coating has an excellent voltage nonlinear response, due to the apparent switching performance, high nonlinear coefficient, and good consistency. The research data and theoretical analysis of this paper have an excellent guiding role for the application of VO2 in the electro-induced phase transition.

This paper proposes a visual management scheme of medical things with a color-change radio frequency identification (RFID) tag. The color-change RFID tag employs a specific RFID tag integrated circuit (IC) and a laminated pH-indicating paper. The IC has energy harvesting and switched ground functions, which enable it to generate electricity to the laminated pH-indicating paper. This phenomenon causes electrolysis of NaCl solution absorbed in the laminated pH-indicating paper. Electrolysis generates alkaline matter to change the color of the pH-indicating paper. This paper gives a new and sensitive structure of the laminated pH-indicating paper. The proposed advanced color-change RFID tag with new laminated pH-indicating paper succeeds in changing its color noticeably at a 1 m distance using an RFID reader radiating 1 W radio waves. The color change was observed 3–5 s after starting radio wave irradiation. The results of this experiment also confirm that the changed color can be held for over 24 h. Furthermore, two demonstrations of the visual management system of medical things (patient clothes and sanitizers) are presented.

Particleboard surface defect detection technology is of great significance to the automation of particleboard detection, but the current detection technology has disadvantages such as low accuracy and poor real-time performance. Therefore, this paper proposes an improved lightweight detection method of You Only Live Once v5 (YOLOv5), namely PB-YOLOv5 (Particle Board-YOLOv5). Firstly, the gamma-ray transform method and the image difference method are combined to deal with the uneven illumination of the acquired images, so that the uneven illumination is well corrected. Secondly, Ghost Bottleneck lightweight deep convolution module is added to Backbone module and Neck module of YOLOv5 detection algorithm to reduce model volume. Thirdly, the SELayer module of attention mechanism is added into Backbone module. Finally, replace Conv in Neck module with depthwise convolution (DWConv) to compress network parameters. The experimental results show that the PB-YOLOv5 model proposed in this paper can accurately identify five types of defects on the particleboard surface: Bigshavings, SandLeakage, GlueSpot, Soft and OliPollution, and meet the real-time requirements. Specifically, recall, F1 score, mAP@.5, mAP@.5:.95 values of pB-Yolov5s model were 91.22%, 94.5%, 92.1%, 92.8% and 67.8%, respectively. The results of Soft defects were 92.8%, 97.9%, 95.3%, 99.0% and 81.7%, respectively. The detection of single image time of the model is only 0.031 s, and the weight size of the model is only 5.4 MB. Compared with the original YOLOv5s, YOLOv4, YOLOv3 and Faster RCNN, the PB-Yolov5s model has the fastest Detection of single image time. The Detection of single image time was accelerated by 34.0%, 55.1%, 64.4% and 87.9%, and the weight size of the model is compressed by 62.5%, 97.7%, 97.8% and 98.9%, respectively. The mAP value increased by 2.3%, 4.69%, 7.98% and 13.05%, respectively. The results show that the PB-YOLOV5 model proposed in this paper can realize the rapid and accurate detection of particleboard surface defects, and fully meet the requirements of lightweight embedded model.

This paper presents a block-chain enabled inkjet-printed ultrahigh frequency radiofrequency identification (UHF RFID) system for the supply chain management, traceability and authentication of hard to tag bottled consumer products containing fluids such as water, oil, juice, and wine. In this context, we propose a novel low-cost, compact inkjet-printed UHF RFID tag antenna design for liquid bottles, with 2.5 m read range improvement over existing designs along with robust performance on different liquid bottle products. The tag antenna is based on a nested slot-based configuration that achieves good impedance matching around high permittivity surfaces. The tag was designed and optimized using the characteristic mode analysis. Moreover, the proposed RFID tag was commercially tested for tagging and billing of liquid bottle products in a conveyer belt and smart refrigerator for automatic billing applications. With the help of block-chain based product tracking and a mobile application, we demonstrate a real-time, secure and smart supply chain process in which items can be monitored using the proposed RFID technology. We believe the standalone system presented in this paper can be deployed to create smart contracts that benefit both the suppliers and consumers through the development of trust. Furthermore, the proposed system will paves the way towards authentic and contact-less delivery of food, drinks and medicine in recent Corona virus pandemic.