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Disabled users who use powered wheelchairs for mobility may suffer back and neck pain. Prolonged exposition to whole-body vibration due to different terrain surfaces may negatively impact the user's health and comfort. This study investigates the impact of whole-body vibration on powered wheelchair users following the ISO-2631 standard. The ISO-2631 standard defines the whole-body vibration limits and quantify its impact on the user's health and comfort. Four users with a range of different weights drive an Electrical Powered Wheelchair (EPW) on five different terrain surfaces. Results indicate that users' weights can impact vibration perception. Additionally, outdoor surfaces generally produce high vertical accelerations, which can negatively impact the user's health and comfort when the EPW is driven for a long period.

Electrostatic sensors have been used to monitor a diverse range of processes and systems that involve movement of charged objects. Several types of preamplifiers are available for signal conditioning of electrostatic sensors, which differ in many aspects. This paper presents a comprehensive comparative study of four types of preamplifiers, namely trans-resistance amplifier, charge amplifier, current sense amplifier and potential amplifier, in order to clarify their differences for correct selection and facilitate proper cabling and electrode design. An equivalent circuit model that quantifies the interaction between the charged object and the electrode using coupling capacitance is established. The voltage outputs of the four preamplifiers are expressed analytically using the potential of the charged object and the object-electrode capacitance that varies as the object moves. In order to produce repeatable and controllable inputs to the electrostatic sensor, a fluctuating electric field is actively generated by applying an excitation voltage signal on an emitting electrode. Under impulse excitation, similarities in the signal waveforms are found between the trans-resistance and current sense amplifiers as well as between the charge and potential amplifiers, apart from the opposite polarities. Both impulse and frequency responses show that the current sense and potential amplifiers are significantly affected by the parasitic capacitances that depend on electrode structure and cabling and measures should be taken to reduce their effects.

Human activity monitoring based on wearable sensors is important in a wide range of biomedical and healthcare applications. Existing wearable sensors using a single unit cannot capture the movements of all body segments. This paper presents a novel wearable electrostatic sensor that can detect limb and torso movements during routine daily activities from any location on the body. Because the electric potential of the human body varies during movements, the sensor measures the potential difference between the body and the electrode for motion sensing. A charge amplifier converts the induced charge on the electrode into a voltage signal, which is further amplified, filtered, digitalized and transmitted via ZigBee. Experimental assessment was carried out by collecting sensor signals from three locations simultaneously while the subject performing different movements. The capability of the sensor to capture limb and torso movements from any location is validated. The characteristics of the sensor are quantified by correlating the sensor signal to simple and cyclic movements. It is found that the sensor signal depends on the sensor’s mounting location on the body, the type of activity and various factors.

The charge density in a flame contains important information about the combustion processes that is difficult to obtain due to fast, complex, and highly exothermic reactions. This paper presents a study of using electrostatic probes to measure the charge density in methane fired diffusion and premixed flames. The sensing principle, practical design, and performance assessment of the electrostatic probe are presented. Comparative experimental studies with a reference ion-current sensor carried out on a combustion test rig indicate that the fluctuation of the signal from the electrostatic probe arises from the variation in the charge density in a flame. A dimensionless index, combining the average of local peak values in the electrostatic signal with the flame oscillation frequency, is adopted as an indicator of the charge density. Experimental results demonstrate that the charge density in a methane diffusion flame has an increasing trend with the fuel flowrate varying from 0.80 L/min to 1.20 L/min. The charge density in a methane-air premixed flame yields a decreasing trend with the equivalence ratio ranging from 0.54 to 0.75, then increases and reaches a local peak at the equivalence ratio of 1.03, and continues to increase when the equivalence ratio varies from 1.03 to 3.50. The charge density in the inner cone is higher than that in the outer cone for diffusion and premixed flames. The results obtained suggest that the developed electrostatic probe and the index can be used to indicate the charge density in diffusion and premixed flames.

This paper aims to design and manufacture an Android-controlled robotic arm for the purpose of picking and placing objects in constrained environments. The motivation of the research is to assess the feasibility of controlling complex real-time operating systems using a personal handheld device, with a future scope to control larger scale operations in the same way. Our robotic arm is produced using rapid prototyping techniques and controlled by an Arduino based development board. It receives control commands from a bespoke Bluetooth app, allowing to select different servo operating modes. The system will be fully controllable from the Android device, allowing the user to manually adjust the position of the arm or running predefined algorithms in automatic mode. Experimental tests are conducted to evaluate the practical limitations of the robotic arm design coupled with the PCB circuitry used as a shield to control the system. The test results show that the system is capable of lifting weights up to 80g with a current draw of 970mA. The automatic control algorithm is found to operate for up to 12 minutes before encountering system bugs or overheating and proves to be a highly repeatable test system with a high level of adaptability. However, the 3D printed PETG is seen to wear over time; and therefore, a more suitable material is recommended to be utilized for fabrication.

Online continuous measurement of the mass flow rate of pneumatically conveyed solids is desirable in the monitoring and optimization of a range of industrial processes, such as food processing, chemical engineering, and power generation. This article introduces a technique for the mass flow rate measurement of pneumatically conveyed solids based on multimodal sensing and data-driven modeling. The multimodal sensing system is comprised of an array of ring-shaped electrostatic sensors, four arrays of arc-shaped electrostatic sensors, and a differential-pressure (DP) transducer. Data-driven models, including artificial neural network (ANN), support vector machine (SVM), and convolutional neural network (CNN), are established through training with statistical features extracted from the postprocessed data from the sensing system. Statistical features are shortlisted based on their importance by calculating the partial mutual information (PMI) between the features and the corresponding reference mass flow rate of solids. Experimental work was conducted on a laboratory-scale rig to train and test the models on both horizontal and vertical pipelines with particle velocity ranging from 10.1 to 36.0 m/s and mass flow rate of solids from 3.2 to 35.8 g/s. Experimental results suggest that the ANN, SVM, and CNN models predict the mass flow rate of solids with a relative error within ±18%, ±14%, and ±8%, respectively, under all test conditions. The predicted mass flow rate measurements with the ANN, SVM, and CNN models are repeatable with a normalized standard deviation within 14%, 8%, and 5%, respectively, under all test conditions.

Coriolis flowmeters have been widely employed in a variety of industrial applications. There is a potential that the measuring tube of a Coriolis flowmeter may be eroded when it is used to measure abrasive fluid such as slurry flow. However, it is challenging to verify the structural health of the flowmeter without process interruptions or using on-site calibration devices such as meter provers. This article presents an in situ structural health-monitoring technique through stiffness diagnosis to identify the potential wear occurring on the measuring tube. To measure the frequency response of a Coriolis flowmeter, which strongly depends on the structural characteristics of the tube, the tube is not only excited at a resonant frequency but also at two additional off-resonant frequencies. Through digital processing of the drive and sensor signals, the frequency response is obtained and a stiffness-related diagnostic parameter (SRDP) is extracted from a Coriolis flowmeter. The proposed stiffness diagnosis technique was experimentally evaluated on a commercial bent-tube Coriolis flowmeter with dilute sand-water slurry flow. The results illustrate that the slight tube erosion is successfully identified when a relative change in SRDP reaches −1%, showing a good capability for an early detection of tube wear. In addition, the outcomes from recalibration with water suggest that, after the erosion occurs, the flowmeter overestimates the mass flowrate and underestimates the flow density.

In a thermal power plant, online measurement of the size distribution of pneumatically conveyed pulverized fuel is essential for the improvement of combustion efficiency and the reduction of pollutant emissions. In this article, an innovative instrumentation system based on acoustic emission (AE) detection and triboelectric sensing is proposed for the on-line continuous measurement of particle size distribution. With a waveguide protruding into the flow, the AE signal is generated from the impacts of particles with the waveguide. The peak voltage of the AE signal is related to the particle size and impact velocity. For the first time, two triboelectric sensor arrays each with three arc-shaped electrodes near to the waveguide are used to measure the impact velocity. Meanwhile, a novel particle sizing algorithm with Gaussian prediction is proposed to reduce the effect of overlapping impacts and environmental noise on the peak distribution. With the known impact velocity measured from the triboelectric sensor arrays and the modified peak distribution, the measurement of particle size distribution is achieved. Experimental tests were conducted on a gas–solids two-phase flow rig to assess the performance of the developed measurement system. Silica sands in three size ranges of 116–750, 61–395, and 10– $246~\mu \text{m}$ , respectively, were used as test particles. The experimental results demonstrate that Spearman’s rank correlation coefficients between the measured and reference size distributions for all test particles are all greater than 0.8, while the discrepancy for each particle size segment is within ±4.8%.

Cross-sectional measurement of particle velocity and concentration in a pneumatic conveying pipe is desirable for the characterisation of particle flow dynamics and determination of particle mass flow rate. In this study, an inner-inserted electrostatic sensor array consisting of nine pairs of electrodes is implemented to measure the cross-sectional velocity and concentration profiling of particles over the whole cross section in a square-shaped pipe. Experimental tests were conducted on both vertical and horizontal pipe sections on a test rig under dilute conditions with different air velocities and particle mass flow rates. Test results show that the slope-shaped particle concentration profile changes to an arch-shaped one when the particles flow from a horizontal pipe to a vertical one. The particle velocity profile is arch-shaped in both vertical and horizontal pipes. A comparative study of cross-sectional mean particle velocity and concentration measured by the developed electrostatic sensor arrays is conducted.

Reliable flame monitoring is essential to enhance the safety of industrial boilers. This paper presents a new self-diagnostic system to measure the oscillation frequency of a burner flame. The system incorporates three sensors including a microphone, a photodiode and an electrostatic electrode and simultaneously acquires three signals. The oscillation frequencies from the three sensors are determined through power spectral analysis, and a fused result of the three frequencies is obtained as the oscillation frequency of the burner flame. Moreover, detection and location of the system faults are realized using a self-diagnostic algorithm through the cross-correlation signal processing. Experimental tests were performed on a laboratory-scale combustion test rig with methane as the test fuel. The results demonstrate that the method is capable of measuring the oscillation frequency of a burner flame. In addition, the results are helpful for the comprehensive analysis of the oscillatory behaviors of burner flames. The self-diagnostic algorithm is able to detect the fault of the monitoring system and no additional self-diagnostic hardware is required.

Reliability analysis is a process aiming to analyze the reliability of a technical system. It provides basic information to asset managers in their planning resources to ensure the system operating at a desired level of performance. Infrastructure systems are an essential asset in modern businesses and its reliable operation is important to the countries as their incapacity will have a debilitating impact on security, national economy, national public health or safety, or any combination of these matters. Thus, ensuring the availability and safety of these infrastructure systems are vital for business operation. As such, research on reliability analysis of infrastructure systems is needed in modern businesses.

Although substantial advancements have been achieved in robot-assisted surgery, the blueprint to existing snake robotics predominantly focuses on the preliminary structural design, control, and human–robot interfaces, with features which have not been particularly explored in the literature. This paper aims to conduct a review of planning and operation concepts of hyper-redundant serpentine robots for surgical use, as well as any future challenges and solutions for better manipulation. Current researchers in the field of the manufacture and navigation of snake robots have faced issues, such as a low dexterity of the end-effectors around delicate organs, state estimation and the lack of depth perception on two-dimensional screens. A wide range of robots have been analysed, such as the i2Snake robot, inspiring the use of force and position feedback, visual servoing and augmented reality (AR). We present the types of actuation methods, robot kinematics, dynamics, sensing, and prospects of AR integration in snake robots, whilst addressing their shortcomings to facilitate the surgeon’s task. For a smoother gait control, validation and optimization algorithms such as deep learning databases are examined to mitigate redundancy in module linkage backlash and accidental self-collision. In essence, we aim to provide an outlook on robot configurations during motion by enhancing their material compositions within anatomical biocompatibility standards.

Dynamic and accurate measurement of instantaneous rotational speed is desirable in many industrial processes for both condition monitoring and safety control purposes. This article presents a novel imaging-based system for instantaneous rotational speed measurement. The low-cost imaging device focuses on the side surface of a rotating shaft without the use of a marker, entailing benefits of noncontact measurement, low maintenance, and wide applicability. Meanwhile, new periodicity determination methods based on the Chirp-Z transform and parabolic interpolation-based autocorrelation algorithm are proposed to process the signal of similarity level reconstructed using an image correlation algorithm. Experimental investigations are conducted on a purpose-built test rig to quantify the effects of the periodicity determination algorithm, frame rate, image resolution, exposure time, illumination conditions, and photographic angle on the accuracy and reliability of the measurement system. Experimental results under steady and transient operating conditions demonstrate that the system is capable of providing measurements of a constant or gradually varying speed with a relative error not greater than ±0.6% over a speed range from 100 to 3000 revolutions per minute (r/min). Under step-change conditions, the proposed system can achieve valid speed measurement with a maximum error of 1.4%.

This paper presents the feasibility of utilizing low cost inertial sensors such as those found in Sony Move, Nintendo Wii (Wii Remote with Wii MotionPlus) and smartphones for upper limb motion monitoring in neurorehabilitation. Kalman and complementary filters based on data fusion are used to estimate sensor 3D orientation. Furthermore, a two-segment kinematic model was developed to estimate limb segment position tracking. Performance has been compared with a high-accuracy measurement system using the Xsens MTx. The experimental results show that Sony Move, Wii and smartphones can be used for measuring upper limb orientation, while Sony Move and smartphones can also be used for specific applications of upper limb segment joint orientation and position tracking during neurorehabilitation. Sony Move's accuracy is within 1.5° for Roll and Pitch and 2.5° for Yaw and position tracking to within 0.5 cm over a 10 cm movement. This accuracy in measurement is thought to be adequate for upper limb orientation and position tracking. Low cost inertial sensors can be used for the accurate assessment/measurement of upper limb movement of patients with neurological disorders and also makes it a low cost replacement for upper limb motion measurements. The low cost inertial sensing systems were shown to be able to accurately measure upper limb joint orientation and position during neurorehabilitation.

Rotational speed of wind turbine blades is an important parameter reflecting the operating and structural health conditions of wind turbines. Traditionally, the rotor speed is measured using inertial measuring units (IMUs). The biggest issue with IMUs is that the measurements drift over time and require constant calibration. This paper presents a direct way of measuring the instantaneous rotational speed of wind turbine blades using a camera and a marker-tracking method. The proposed measurement method is assessed by conducting a series of simulation experiments under different conditions – fixed speed, stepped varying speed, and linear varying speed. Results demonstrate that when using a camera with a frame rate of 30 fps (frames per second), the marker-tracking method yields a relative error within ±0.5% at the speed between 5 to 30 rpm (revolutions per minute). Compared to the image-correlation method, the marker-tracking method provides better results in terms of accuracy and reaction time, especially under varying speed conditions.

Prognostics and health management (PHM) has become a crucial aspect of the management of engineering systems and structures, where sensor hardware and decision support tools are deployed to detect anomalies, diagnose faults and predict remaining useful lifetime (RUL). Methodologies for PHM are either model-driven, data-driven or a fusion of both approaches. Data-driven approaches make extensive use of large-scale datasets collected from physical assets to identify underlying failure mechanisms and root causes. In recent years, many data-driven PHM models have been developed to evaluate system’s health conditions using artificial intelligence (AI) and machine learning (ML) algorithms applied to condition monitoring data. The field of AI is fast gaining acceptance in various areas of applications such as robotics, autonomous vehicles and smart devices. With advancements in the use of AI technologies in Industry 4.0, where systems consist of multiple interconnected components in a cyber–physical space, there is increasing pressure on industries to move towards more predictive and proactive maintenance practices. In this paper, a thorough state-of-the-art review of the AI techniques adopted for PHM of engineering systems is conducted. Furthermore, given that the future of inspection and maintenance will be predominantly AI-driven, the paper discusses the soft issues relating to manpower, cyber-security, standards and regulations under such a regime. The review concludes that the current systems and methodologies for maintenance will inevitably become incompatible with future designs and systems; as such, continued research into AI-driven prognostics systems is expedient as it offers the best promise of bridging the potential gap.

Carbon capture, utilisation and storage (CCUS) will play a critical role in future decarbonisation efforts to meet the Paris Agreement targets and mitigate the worst effects of climate change. Whilst there are many well developed CCUS technologies there is the potential for improvement that can encourage CCUS deployment. A time and cost-efficient way of advancing CCUS is through the application of machine learning (ML). ML is a collective term for high-level statistical tools and algorithms that can be used to classify, predict, optimise, and cluster data. Within this review we address the main steps of the CCUS value chain (CO2 capture, transport, utilisation, storage) and explore how ML is playing a leading role in expanding the knowledge across all fields of CCUS. We finish with a set of recommendations for further work and research that will develop the role that ML plays in CCUS and enable greater deployment of the technologies.

Woodchips as a common biomass are widely used in industrial processes and our daily lives. The moisture content in woodchips has a significant effect on the processing and combustion efficiency of woodchips. Therefore, it is necessary to develop a suitable method to measure the moisture content of woodchips. Capacitive sensors are widely used in various fields due to their simple structure, low cost and non-destruction to the samples. Because of the uniform sensitivity distribution compared to the parallel plate sensor design, a helical capacitive sensor is used in this paper to measure the moisture content of woodchips. The structure of the sensor is firstly optimized based on the orthogonal test method using a finite element model. Then, the influence of particle size and packing density of biomass on the capacitance readings is investigated. Finally, the moisture content is predicted through data driven modelling. Woodchip samples with different particle sizes, moisture content and packing densities are used to verify the model. It is found that the relative error between the predicted and reference values is within ±10% over the range of moisture contents from 7% to 49%.

In-line measurement of the mass flow rate of solids in pneumatic conveying pipelines is essential for the efficient and optimized operation of many industrial processes. This paper presents a comparative study of using induced and transferred charges from non-intrusive electrodes exposed to the particle flow for mass flow rate measurement. A novel signal conditioning circuit, which consists of a current sense amplifier and a charge amplifier, is designed to convert the induced and transferred charges into two separate voltage signals. Empirical measurement models that relate the particle velocity, the root-mean-square (r.m.s) magnitude of the induced charge signal and the slope of the transferred charge signal to the mass flow rate are proposed. Experiments were undertaken using electrodes of different widths and under different mass flow rate and particle velocity conditions. Results obtained show that both the r.m.s magnitude of the induced charge signal and the slope of the transferred charge signal increase with the mass flow rate and the velocity of particles. In general, the measurement results using the induced and transferred charges from either the narrow or the wide electrode are similar. However, the method based on the transferred charge is less reliable due to confined sensing area and electrode charging by particles adhered to the electrode surface.

The measurement of automated and fast focusing on the improvement of speed and accuracy is an important issue in industrial inspection and biomedical microscopy. In this study, we developed a novel optical imaging system in which varifocal lenses are used to characterize the 3D surface topography of samples. The performance of the proposed system was evaluated using twelve focusing algorithms. Experimental results demonstrate the feasibility and effectiveness of the proposed system in the near real-time construction of multi-focus fusion images with large depth of field from which to derive 3D surface profiles.

Thermodiffusion, or the Soret phenomenon, is well understood in simple systems, but in multicomponent and polyvalent electrolyte systems the process becomes more complicated due to the coupling of fluxes. We experimentally investigate the time evolution of a concentration gradient generated by thermodiffusion of a polyelectrolyte (poly(sodium 4-styrene sulfonate), NaPSS) in a 1:1 supporting electrolyte. We also derive and solve the transport equations that are used to extract the Soret coefficient from the experimental observations. It is shown that NaPSS thermodiffusion in NaCl is strongly dependent on concentration, with almost 100% thermal separation in concentrations below 15 nmol L−1. Moreover, the results suggest that the supporting electrolyte can greatly influence the thermodiffusion of the polyelectrolyte, in some cases possibly even reversing the direction of the flux from the usual case of enrichment at the cold side.

The main objective of this work comprises the investigation of biodiesel production from rapeseed oil using potassium impregnated Fe3O4-CeO2 nanocatalyst. The various concentration of potassium impregnated Fe3O4-CeO2 was screened for catalytic conversion of rapeseed oil to triglyceride methyl ester. The 25 wt % potassium impregnated Fe3O4-CeO2 nanocatalyst showed best biodiesel production. Nanocatalyst was characterized by FTIR, XRD, SEM, TEM, BET and Hammett indicator for basicity test. The characterization of biodiesel was performed with GC-MS, 1H and 13C NMR. Moreover, the optimum reaction parameters such as catalyst amount (wt %), oil to methanol ratio, reaction time and reaction temperature for transesterification reaction was analyzed and yield was determined by 1H NMR. The maximum yield of 96.13% was obtained at 4.5 wt % catalyst amount, 1:7 oil to methanol ratio at 65 °C for 120 min. The properties of biodiesel such as acid value and kinematic viscosity were observed as 0.308 mg KOH/g and 4.37 mm2/s respectively. The other fuel parameters such as flash point and density were also determined. The reusability of catalyst was observed and it showed stability up to five cycles without considerable loss of activity. The recovery of excess methanol after transesterification reaction was achieved using distillation process setup.

Sulfur compounds present in high-temperature gases from various industrial sources have a negative influence on the permeability of different kinds of membranes. In this study, we present a general and efficient strategy to design and prepare two asymmetric membranes for CO2 separation that are resistant to H2S. The asymmetric membranes, mainly composed of one adsorbed layer for H2S consumption and one dense ceramic-carbonate layer for CO2 separation, show not only high CO2 permeation flux but also remarkably stable permeation behavior under an H2S-containing atmosphere. The sulfur-resistant stability times of the asymmetric membranes are approximately 10–12 times higher than the single ceramic-carbonate dual-phase membrane. The adsorbed layer of the asymmetric membranes can react with H2S to form Ce-O-S phases, gradually causing deactivation of the adsorbed layer. However, the adsorbed layer can be regenerated in the oxygen-containing gas stream above 850 °C, which can effectively remove the sulfur content from the adsorbed layer, making recycle of the membrane possible. Sulfur accumulated in the adsorbed layer of the membrane as a Ce2O2S phase, can be oxidized into SO2 under air stream and elemental sulfur (S) under a 2.5% O2/He gas stream. These asymmetric membranes thus possess high permeation stability in the H2S-containing atmosphere with good regenerability and also have potential in collection and removal of sulfur impurities from gas streams.

Aqueous-phase reforming (APR) is a quite new technology for the production of hydrogen and light hydrocarbons from aqueous-organic mixtures in a single-stage process. This manuscript analyzes the APR of representative model compounds of bio-oil aqueous fraction, including acetic acid, ethanol, 1-hydroxypropan-2-one (acetol) and benzene-1,2-diol (catechol), as well as a mixture of all of them. The APR experiments were conducted at 230 °C and 3.2 MPa over three different Ni-based catalysts, including spinel NiAl2O4 , and supported Ni/CeO2-γAl2O3 and Ni/La2O3-αAl2O3 . The reactivity of the model compounds varied largely in the order: acetol > ethanol > catechol > acetic acid, whereas the H2 production decreased in the following order: ethanol ≫> acetol > acetic acid > catechol. Based on the product distribution obtained, the reaction pathways in the APR of each model compound have been proposed. In the APR of the mixture, the Ni/La2O3-αAl2O3 led to the highest H2 yield but was affected by Ni leaching, whereas spinel NiAl2O4 showed a much higher stability. Therefore, the Ni-spinel catalyst showed a good potential for H2 production by APR of bio-oil aqueous fraction.

Ni 1-x Zn x O-Ce 0.8 Sm 0.2 O 1.9 is studied as an anode material for solid oxide fuel cells with hydrogen and methanol as fuels. After reduction, Zn is incorporated into the lattice of Ni when x is less than 0.5, while NiZn alloy accompanied with ZnO is formed when x reaches 0.8. The electrochemical oxidation process of H 2 on the anode is investigated with a symmetric cell under various H 2 partial pressures. The addition of Zn increases the electron cloud density of Ni and thus weakens the adsorbing strength of H on Ni, accelerating the surface diffusion of H species, which is the rate determining step when the content of Zn is lower than 0.5. ZnO in the reduced Ni 0·2 Zn 0·8 O- Ce 0.8 Sm 0.2 O 1.9 anode facilitates H spillover, resulting in the variation of the rate determining step and the highest activity of the anode. The cell with Ni 0·2 Zn 0·8 O- Ce 0.8 Sm 0.2 O 1.9 anode shows the highest performance with both H 2 and methanol fuels at 700 °C. ZnO also improves coking resistance of NiO-Ce 0.8 Sm 0.2 O 1.9 anode.

We have developed a rapid and sensitive universal peptide-based time-resolved luminescence assay for detection of enzymatic post-translational modifications (PTMs). PTMs play essential roles in intracellular signaling and cell regulation, thus providing functional protein diversity in cell. Due this, impaired PTM patterns have been linked to multiple disease states. Clear link between PTMs and pathological conditions have also driven assay development further, but still today most of the methodologies are based on single-specificity or group-specific PTM-recognition. We have previously introduced leuzine-zipper based peptide-break technology as a viable option for universal PTM detection. Here, we introduce peptide-break technology utilizing single-label homogeneous quenching resonance energy transfer (QRET) and charge-based peptide-peptide interaction. We demonstrate the functionality of the new assay concept in phosphorylation, deacetylation, and citrullination. In a comparable study between previously introduced leucine-zipper and the novel charge-based approach, we found equal PTM detection performance and sensitivity, but the peptide design for new targets is simplified with the charged peptides. The new concept allows the use of short

openaire: EC/H2020/730480/EU//ITERAMS Calcium sulfate is one of the most common inorganic salts with a high scaling potential. The solubility of calcium sulfate was modeled with the Pitzer equation at a temperature range from 273.15 to 473.15 K from published solubility data, which was critically evaluated. Only two Pitzer parameters, β(1) and β(2), with simple temperature dependency are required to model the solubility with excellent extrapolating capabilities up to 548.15 K. The stable temperature range for gypsum is 273.15-315.95 K, whereas above 315.95 K the stable phase is anhydrite. Hemihydrate is in the metastable phase in the whole temperature range, and the obtained metastable invariant temperature from gypsum to hemihydrate is 374.55 K. The obtained enthalpy and entropy changes at 298.15 K for the solubility reactions are in good agreement with literature values yielding solubility products of 2.40 × 10-05, 3.22 × 10-05, and 8.75 × 10-05 for gypsum, anhydrite, and hemihydrate, respectively. The obtained Pitzer model for the CaSO4-H2O system is capable of predicting the independent activity and osmotic coefficient data with experimental accuracy. The mean absolute average error of activity coefficient data at 298.15 K is less than 2.2%. Our model predicts the osmotic coefficient on the ice curve within 1.5% maximum error.

Oxychlorination of ethene was conducted in a microreactor (150–375 °C) over a thin layer of CeO2 prepared in the current work with the specific surface area of 80 m2/g and compared with the same reaction in millireactors (250–500 °C). The kinetic analysis revealed influence of the ethene concentration on the apparent activation energy which was different in micro- and millireactors. The previously developed reaction network was completed by including two parallel reactions for formation of ethylchloride and vinylchloride and two consecutive reactions accounting for formation of dichloroethane and vinylchloride via ethyl chloride. The reaction orders with respect to HCl and O2 in the microreactor were comparable with the literature data for millireactors. Kinetic modeling was successfully carried for all reactants by using a steady state model of a packed bed reactor.

l -proline was used to prepare chiral, tridentate amino acid phenol proligands H2L1–4. These proligands react with vanadium precursors VO(acac)2, VOSO4∙5H2O and VO(OPr)3 in methanol to form the corresponding oxidoalkoxidovanadium( v ) complexes 1–4. The complexes crystallize from methanol, and are octahedrally coordinated with a general formula [VO(L1–4)(OMe)(MeOH)]. In solution, however, they adopt several different conformations or isomeric structures depending on the solvent.

A rapid ultra-high performance liquid chromatography–atmospheric pressure chemical ionization tandem mass spectrometric (UHPLC-APCI-MS/MS) method was developed for the analysis of vitamin K compounds: phylloquinone (PK) and menaquinones (MK-n). Non-chlorinated mobile phase composition was optimized for separation of eight vitamin K compounds on a reversed phase column in 10 min. Sample treatment with liquid and solid phase extractions and by the use of MK-4 as an internal standard enabled the quantitation of microgram level of vitamin K compounds in food. The method was used to screen and quantitate vitamin K from 17 fermented food products. The highest amount of PK was detected in kimchi (42 µg/100 g), whereas the highest MK-7 content was detected in natto (902 µg/100 g). Some MK-9 was present in kefir (5 µg/100 g). Two Chinese fermented soybean pastes contained significant amount of MK-6 (5–36 µg/100 g), MK-7 (12–86 µg/100 g), and MK-8 (22–44 µg/100 g).

A novel microtiter plate array for the quantification and identification of metal ions in drinking water was compared to human taste panel analysis. The array is based on nonspecific interactions between analyte metal ions and lanthanide chelates with non-antenna and antenna ligands, leading to a luminescence signal profile unique to sample components. The performance of the method was demonstrated in the detection of Cu2+ and Fe2+ ions in active coal filtered and nonfiltered household water. The sensitivity and objectiveness was compared to human taste panel analysis. Detection limits of

The present study aimed to investigate the reciprocal effects of Phoradendron perrottetii (mistletoe) and T. guianensis (host plant) regarding their polyphenol composition. Taking into account that tannins are important molecules in plant defense and their biosynthesis tends to be enhanced when a species is exposed to stress, we address the following questions: (1) Are the tannins found in our model species important in the interaction between host and mistletoe? (2) Does the presence of mistletoe induce changes in the content of tannins and other polyphenols in the host plant? (3) Do we find differences between the tannin sub-groups in the responses of the host plant to mistletoe? (4) Could the observed differences reflect the relative importance of one tannin group over another as chemical defense against the mistletoe? Using a polyphenol and tannin group-specific MRM methods we quantified four different tannin sub-groups together with flavonoid and quinic acid derivatives by ultra-performance liquid chromatography tandem mass spectrometry together with the oxidative and protein precipitation activities of leaves and branches of Tapirira guianensis and Phoradendron perrottetii. We selected leaves and branches of six non-parasitized trees of T. guianensis. Leaves and branches of nine individuals of T. guianensis parasitized by P. perrottetii were also sampled. For each parasitized tree, we sampled an infested branch and its leaves, as well as a non-infested branch and its leaves. Infested branches were divided into three groups: gall (the host-parasite interface), proximal, and distal region. Both proanthocyanidins and ellagitanins seem to be important for plant-plant parasitism interaction: host infested tissues (gall and surrounding regions) have clearly less tannin contents than healthy tissues. Mistletoe showed high levels of quinic acid derivatives and flavonoids that could be important during hastorium formation and intrusion on host tissues, suggesting a defense mechanism that could promote oxidative stress together with an inhibition of mistletoe seed germination, consequently avoiding secondary infestations. Polyphenol detected in T. guianensis-P. perrottetii interaction could play different role as plant-mistletoe strategies of survival.

The present work offers a study on the engineering implications of the recovery of valuable fractions from industrially collected lithium battery (LIB) waste by mechanical and hydrometallurgical processes in HCl media. Direct leaching of LIB waste provides a possibility for Li extraction, a component that is lost into the slag fraction in the state-of-art high temperature processes. The challenges arising from the heterogeneous composition of industrial battery waste are highlighted, and the behavior of main metals present such as Co, Cu, Li, Mn, Ni and Al is observed. It is shown that mechanical separation processes can form fractions rich on Cu and Al, although subsequent refining stages are necessary. Regarding direct leaching, fast kinetics were found, as complete Li dissolution can be achieved in ca. 120 min. Furthermore, high solid/liquid ratio (>1/10) is required to increase metal value concentrations, resulting in a viscous slurry due to the graphite, plastics and other undissolved materials, which challenges filtration and washing of leach residue. Neutralization of the product liquid solution (PLS) result in co-precipitation of valuable battery metals along with Fe and Al. The highest value of LIBs lies in Co, subjected for solvent extraction (SX) or direct precipitation to make an intermediate product. SX can provide selectivity whereas Na2CO3 precipitation provides a fast route for Co-Ni bulk production. Li2CO3 precipitation from the remaining PLS is possible as zabuyelite - however, due to heterogeneity of the battery waste, the recovery of Li2CO3 with battery-grade purity remains a difficult task to be achieved by direct precipitation route.

Metal–support interfaces form an active site for many important catalytic reactions. The modeling of these interfacial sites calls for approximations to set up a structure model, which in turn may ...

The present work is directed toward preparation, structure and optical property characterization of tetrazole-containing Cu(I) compounds. By means of the alternating-current electrochemical techniq...

The tetrapyrrole chromophore biliverdin IXα (BV) in the bacteriophytochrome from Deinococcus radiodurans (DrBphP) is usually assumed to be fully protonated, but this assumption has not been systematically validated by experiments or extensive computations. Here, we use force field molecular dynamics simulations and quantum mechanics/molecular mechanics calculations with density functional theory and XMCQDPT2 methods to investigate the effect of the five most probable protonation forms of BV on structural stability, binding pocket interactions, and absorption spectra in the two photochromic states of DrBphP. While agreement with X-ray structural data and measured UV/vis spectra suggest that in both states the protonated form of the chromophore dominates, we also find that a minor population with a deprotonated D-ring could contribute to the red-shifted tail in the absorption spectra.

Chalcogenide-capped triiron clusters [Fe3(CO)7(μ3-CO)(μ3-E)(μ-dppm)] and [Fe3(CO)7(μ3-E)2(μ-dppm)] (E = S, Se) have been examined as proton-reduction catalysts. Protonation studies show that [Fe3(CO)9(μ3-E)2] are unaffected by strong acids. Mono-capped [Fe3(CO)7(μ3-CO)(μ3-E)(μ-dppm)] react with HBF4.Et2O but changes in IR spectra are attributed to BF3 binding to the face-capping carbonyl, while bicapped [Fe3(CO)7(μ3-E)2(μ-dppm)] are protonated but in a process that is not catalytically important. DFT calculations are presented to support these protonation studies. Cyclic voltammetry shows that [Fe3(CO)9(μ3-Se)2] exhibits two reduction waves, and upon addition of strong acids, proton-reduction occurs at a range of potentials. Mono-chalcogenide clusters [Fe3(CO)7(μ3-CO)(μ3-E)(μ-dppm)] (E = S, Se) exhibit proton-reduction at ca.-1.85 (E = S) and -1.62 V (E = Se) in the presence of p-toluene sulfonic acid (p-TsOH). Bicapped [Fe3(CO)7(μ3-E)2(μ-dppm)] undergo quasi-reversible reductions at -1.55 (E = S) and -1.45 V (E = Se) and reduce p-TsOH to hydrogen but protonated species do not appear to be catalytically important. Current uptake is seen at the first reduction potential in each case, showing that [Fe3(CO)7(μ3-E)2(μ-dppm)]- are catalytically active but a far greater response is seen at ca.-1.9 V being tentatively associated with reduction of [H2Fe3(CO)7(μ3-E)2(μ-dppm)]+. In general, selenide clusters are reduced at slightly lower potentials than sulfide analogues and show slightly higher current uptake under comparable conditions. peerReviewed

The title compound, [Fe(C27H41N10O3)](PF6)2, is an example of an iron(II) spin-crossover compound. In this compound, C⋯F and CH⋯F/O contacts, present between the cations and anions, extend the structure into a three-dimensional supra­molecular network., In the complex cation of the title compound, [Fe(C27H41N10O3)](PF6)2, the tripodal tris­{4-[1-(2-meth­oxy­eth­yl)imidazol-2-yl]-3-aza­but-3-en­yl}amine ligand is coordinated to an FeII ion through the nitro­gen atoms of three imidazole and three imino groups. The Fe atom exhibits a distorted octa­hedral geometry. In the crystal, l and d anti­podes are arranged in layers in the bc plane. Weak C⋯F and C—H⋯F/O contacts exist between the ligands of the complex cation and the PF6 − anions, generating a three-dimensional network. At 120 K, the FeII ion is in a low-spin state, with an average Fe—N bond distance of 1.970 (2) Å. On heating, the FeII ion converts to the high-spin state, as demonstrated by magnetic susceptibility measurements.

Synthetic structural materials of high mechanical performance are typically either of large weight (for example, steels, and alloys) or involve complex manufacturing processes and thus have high cost or cause adverse environmental impact (for example, polymer-based and biomimetic composites). In this perspective, low-cost, abundant and nature-based materials, such as wood, represent particular interest provided they fulfill the requirements for advanced engineering structures and applications, especially when manufactured totally additive-free. Here, we report on a novel all-wood material concept based on delignification, partial surface dissolution using ionic liquid (IL) followed by densification resulting in a high-performance material. A delignification process using sodium chlorite in acetate buffer solution was applied to controllably delignify the entire bulk wooden material while retaining the highly beneficial structural directionality of wood. In a subsequent step, obtained delignified porous wood template was infiltrated with an IL 1-ethyl-3-methylimidazolium acetate, [EMIM]OAc and heat activated at 95 degrees C to partially dissolve the fiber surface. Afterward, treated wood was washed with water to remove IL and hot-pressed to gain a very compact cellulosic material with fused fibers while retaining unidirectional fiber orientation. The obtained cellulose materials were structurally, chemically, and mechanically characterized revealing superior tensile properties compared to native wood. Furthermore, suggested approach allows almost 8-fold tensile strength improvement in the direction perpendicular to fiber orientation, which is otherwise very challenging to achieve.

A WO3/γ-Al2O3 catalyst prepared by an incipient-wetness impregnation method is employed in the selective conversion of enzymatic hydrolysis lignin (EHL) into various alkylphenols in supercritical e...

The reactions between [VO(acac)2] (acac– = acetylacetonate) and the tripodal amino bisphenols 6,6′-(((2-morpholinoethyl)azanediyl)bis(methylene))bis(2,4-di-tert-butylphenol) (H2L1) and 6,6′-(((thiophen-2-ylmethyl)azanediyl)bis(methylene))bis(2,4-di-tert-butylphenol) (H2L2) as well as the tetradentate amino phenol 2,2′-((3,5-di-tert-butyl-2-hydroxybenzyl)azanediyl)bis(ethan-1-ol) (H3L3) afford the complexes [VO(L1)(OMe)] (1), [VO(L2)(acac)] (2) and [VO(L3)] (3), correspondingly. Complexes 1 and 3 can also be prepared using VOSO4·xH2O or [VO(OPr)3] as vanadium precursors. When [VO(acac)2] or VOSO4·xH2O is used, mononuclear oxovanadium(V) complexes are formed upon oxidation of the metal precursor. Single crystal X-ray structure analysis show that complexes 1 and 2 have distorted octahedral coordination spheres, in which the amino bisphenolate coordinates in a tetradentate or tridentate manner, respectively, and the coordination spheres are completed by methoxy or acetylacetonato ligands. Complex 3 has a slightly distorted trigonal bipyramidal geometry with an NO4 coordination environment. All three complexes can catalyze epoxidation of cis-cyclooctene at 50 °C with tert-butyl hydroperoxide (TBHP) or H2O2 as an oxygen source, and sulfoxidation of thioanisole or methyl-p-tolylsulfide proceeds at 25 °C using the same oxidants.

Rare earth elements (REEs) are highly important in the modern society as a result of their wide use in various fields of industry. Their high supply risk and increase in demand has led to classification as critical materials, and consequently, new resources for REEs are being prospected widely. Coal fly ash has been suggested as a possible secondary resource for REEs, but very little information is available regarding REE occurrence in biomass or peat derived fly ash. In this paper, fly ash samples from commercial power plants using peat and biomass as fuel were studied for REEs. The average concentration of REEs was 530 ppm, with up to 920 ppm in one fly ash. Five out of seven fly ashes were identified promising for profitable REE recovery according to outlook coefficients of >0.7 and critical REE content of >30%. Four fly ashes were found to exhibit medium REE enriched distributions, whereas three fly ashes displayed light REE enriched distributions. These enriched distribution patterns, as well as the observed Gd, Ce, Eu, La, and Y anomalies in the patterns, are proposed to originate mainly from the granitic bedrock at the fuel source. Additionally, positive correlation between REEs and iron was found, indicating REE association with iron minerals. peerReviewed

Insoluble residue (INS) is a lignin-rich fraction of brewer's spent grain (BSG) that also contains β-glucan and arabinoxylan, the major constituents of dietary fiber. We investigated the effects of INS in diet-induced obese mice in terms of lipid metabolism and metabolic diseases. Male mice (C57bl6) were fed a high-fat diet (HFD), a HFD + 20% INS, a HFD + 20% cellulose (CEL), a HFD with a combination of 20% INS-CEL (1:1), or a control diet for 14 weeks. Insulin and glucose tolerance tests were performed after 12 weeks. Fasting plasma lipids, bile acid, and fecal bile acid were measured after 14 weeks of feeding, and tissues were collected for gene expression analysis. Body weight gain was significantly reduced with all fibers, but only INS and INS-CEL decreased fasting plasma low-density lipoprotein cholesterol and total cholesterol compared to HFD. CEL and INS-CEL significantly improved insulin resistance. Fecal bile acids were significantly increased by all fibers, but there was no change in plasma bile acid. Clostridium leptum was increased with all fibers, but universal bacterial diversity was only with INS and INS-CEL. In addition, INS significantly increased the abundance of Bacteriodes, while CEL decreased Atopobium and Lactobacillus. INS feeding significantly upregulated various genes of cholesterol and bile acid metabolism, such as Srebp2, Hmgcr, Ldlr, Cyp7a1, Pparα, Fxr, and Pxr, in the liver. INS, INS-CEL, and CEL significantly attenuated liver steatosis. Our results suggest that INS from BSG induced beneficial systemic changes in mice via gut microbiota, bile acids, and gene expression in the liver.

Proton diffusion (PD) across biological membranes is a fundamental process in many biological systems, and much experimental and theoretical effort has been employed for deciphering it. Here, we report on a spectroscopic probe, which can be tightly tethered to the membrane, for following fast (nanosecond) proton transfer events on the surface of membranes. Our probe is composed of a photoacid that serves as our light-induced proton source for the initiation of the PD process. We use our probe to follow PD, and its pH dependence, on the surface of lipid vesicles composed of a zwitterionic headgroup, a negative headgroup, a headgroup that is composed only from the negative phosphate group, or a positive headgroup without the phosphate group. We reveal that the PD kinetic parameters are highly sensitive to the nature of the lipid headgroup, ranging from a fast lateral diffusion at some membranes to the escape of protons from surface to bulk (and vice versa) at others. By referring to existing theoretical models for membrane PD, we found that while some of our results confirm the quasi-equilibrium model, other results are in line with the nonequilibrium model. peerReviewed

In this study, tannin-furanic-based foams enforced with H3BO3 and ZnCl2 are investigated, as well as their properties such as mechanical strength, specific surface area, and pore size distribution. From an industrial point of view, the aforementioned properties of these foams play a key role when used as catalyst, adsorbent, or gas storing materials. Therefore, this study aims to prove that such enforced tannin-furanic foams are promising materials for these types of applications. According to the results, materials that are up to five times stronger can be achieved by carbonizing the foams in comparison to maturing them. With physical activation, it was possible to obtain a specific surface area as high as 845 m2/g with a pore volume of up to 0.35 cm3/g. Chemical activation, using ZnCl2 as the activating agent, produced a specific surface area and pore volume of 737 m2/g and 0.31 cm3/g. However, the pore sizes were mostly microporous, independently of activation procedure used.

The reaction of 4-aminopyridine (4-AP) with ICl in a 1:1 molar ratio in CH2Cl2 produced the expected charge-transfer complex [4-NH2-1λ4-C5H4N-1-ICl] (1·ICl) and the ionic species [(4-NH2-1λ4-C5H4N)2-1μ-I+][Cl–] (2·Cl–) in a 2:1 relation, as indicated by 1H NMR spectroscopy in solution. In contrast, only the ionic compound [(4-NH2-1λ4-C5H4N)2-1μ-I+][IBr2–] (2·IBr2–) was observed in the analogous reaction with IBr. The reaction between 4-AP and I2 in a 1:1 molar ratio also afforded two components, one of which was identified as the congeneric cation in [(4-NH2-1λ4-C5H4N)2-1μ-I+][I7–] (2·I7–) that contains a polyiodide anion as a result of transformation in a 1:2 molar ratio between the starting materials. In all of these ionic products, the crystal structures feature an iodonium ion, I+, trapped between two 4-AP rings through N···I+···N contact. Surprisingly, the reaction of 4-AP with Br2 in CH2Cl2 resulted in an immediate protonation of the 4-aminopyridine (1H NMR) and [4-NH2-1λ4-C5H4N-1-H+][Br–] (3·Br–) was characterized as the main product. A subsequent peculiar bromination–dimerization process afforded the novel pyridyl-pyridinium cations {3,3′,5′-Br3-1λ4-[1,2′-(C5H4N)2]-4,4′-(NH2)2}+[X–] (4·Br–, 4·Br3–) and {3′,5′-Br2-1λ4-[1,2′-(C5H4N)2]-4,4′-(NH2)2}+[X–] (5·Br–, 5·Br3–). Compounds 1–5 as well as two protonated species, [4-NH2-1λ4-C5H4N-1-H+]2[Cl–][I3–] (32·Cl–·I3–) and [(4-NH2-1λ4-C5H4N)2-1μ-H+][I–] (6·I–), all display extended 3D networks supported by halogen and hydrogen bonding in the solid state. peerReviewed

When V2O5 is used for the deoxygenation of guaiacol in methanol, it is reduced in situ to haggite structured V4O6(OH)4. Guaiacol prevents further reduction of the haggite phase in methanol and haggite catalyzes the partial deoxygenation of guaiacol. Haggite is a metastable redox catalyst for the deoxygenation of guaiacol, which follows the reverse Mars–van Krevelen mechanism. In addition, haggite is also a Lewis acid catalyst and catalyzes the alkylation of guaiacol with methanol as the alkylation reagent. The main products of the guaiacol deoxyalkylation are 2,6-dimethylphenol, 2-methoxy-6-methylphenol, 2,4,6-trimethylphenol, 2,3,6-trimethylphenol, 2,3,5,6-tetramethylphenol and 6-methyl-2-tert-butylphenol. Oligomerization takes place during the reaction but it is reversible. When the reaction is performed at 300 °C for 6 h, the 83.5% total selectivity for alkylphenols is achieved with a 99.0% conversion.

Recent years has seen an increase in collaboration between academics and artisans in the field of gastronomy. Accounts have been given both in research reports and elsewhere, often as recurring stories framed as best-practice examples or stories of success and innovation. In the work herein, we have sought to study the conditions, possibilities, and limitations of such collaborations in depth. Theoretically, the work is framed in various forms of disciplinarity (inter-, multi- and transdisciplinarity), seeking to shed light on collaboration between, or across, disciplines and professions. The empirical material consists of answers received from 43 food professionals from Finland (9), Norway (8), Spain (15), USA (11), to an online survey concerning their views of interaction/collaboration between chefs and researchers, i.e., gastronomy and sciences. The study follows a mixed-methods design in data collection and analysis, featuring both quantitative survey data and written accounts. The results indicate that the chefs, most of which already have experience with such collaboration, are knowledge-oriented, innovation-oriented, and expressly positive to cross-discipline/cross-profession collaboration. Furthermore, they believe that both chefs and researchers may benefit from such collaboration, and the majority believe they would personally be able to contribute to the work of researchers. Lack of time and resources are stated as main obstacles, but not unanimously. Other barriers to collaboration are getting in touch with researchers, disruption in a hectic and high-paced workday, and domain-specific language/discourse. The results are discussed in relation to modes of collaboration across and between disciplines as well as existing research on science and gastronomy.