Search

The ability to measure and capture real-time unit operational data has significant benefits during dairy processing, whether it is the basics, such as measuring temperature, pressure, and flow rates, or more recent developments in the case of in-line viscosity and product-compositional measurements. This rapid data collection has helped increase profitability by reducing energy costs, minimizing product loss, and allowing automated control. Advances in technology have allowed for in-line measurements of the composition and some physical attributes such as particle size and viscosity; however, an attribute that spans both compositional and physical attributes is pH, directly influenced by composition but also environments, such as temperature and dry matter content. pH is measured for a plethora of reasons, such as a measure of milk quality (microbial spoilage), acidification of casein, cheese production, maintaining optimum conditions during protein hydrolysis, etc. However, very little is published on the fundamentals of pH and pH measurement in dairy processing; rather, it is usually a cause-and-effect phenomenon. This review visits one of the oldest analytical considerations in the dairy industry and re-examines how it is affected by product composition and processing conditions.

The winning of critical raw materials from secondary resources, e.g., from abandoned mines, mining residues, electronic waste or low-grade ores, is a potential source with promising outcomes due to innovative and more efficient extraction methods. The research and education mine “Reiche Zeche” at the TU Bergakademie Freiberg, Germany offers a scientific lab in a real application environment for an in-situ bioleaching section from a low-grade sulfide ore vein with on-site associated membrane downstream processing. The evaluation and resumption of previous research activities showed both the feasibility and the potential for further up-scaling. But there was also potential evaluated for improving the effectiveness, especially in terms of individual process elements within the leaching and membrane cycle as well as regarding microbiology. Based on this, further optimization was carried out and effectiveness was evaluated and compared to the prior state. The results regarding the leaching outcome proved that process optimization leads to stable and continuous leaching process operations as well as to improved and more favorable conditions for the microorganisms due to the implementation of a bioreactor and changing the whole leaching operation from a direct into an indirect process. Furthermore, cleaning in place (CIP) resulted in the maintenance of selectivity despite discontinuous membrane process operation.

This work presents a new ultra-high vacuum cluster tool to perform systematic studies of the early growth stages of atomic layer deposited (ALD) ultrathin films following a surface science approach. By combining operando (spectroscopic ellipsometry and quadrupole mass spectrometry) and in situ (X-ray photoelectron spectroscopy) characterization techniques, the cluster allows us to follow the evolution of substrate, film, and reaction intermediates as a function of the total number of ALD cycles, as well as perform a constant diagnosis and evaluation of the ALD process, detecting possible malfunctions that could affect the growth, reproducibility, and conclusions derived from data analysis. The homemade ALD reactor allows the use of multiple precursors and oxidants and its operation under pump and flow-type modes. To illustrate our experimental approach, we revisit the well-known thermal ALD growth of Al2O3 using trimethylaluminum and water. We deeply discuss the role of the metallic Ti thin film substrate at room temperature and 200 °C, highlighting the differences between the heterodeposition (10 cycles) growth regimes at both conditions. This surface science approach will benefit our understanding of the ALD process, paving the way toward more efficient and controllable manufacturing processes.

This study introduces an innovative photolithography-based method for patterning ionic and inorganic particle materials such as silver iodide (AgI). Conventional methods lack precision when patterning powdered materials, which limits their applicability. The proposed method stacks layers of a particle material (AgI) and negative-tone photoresist for simultaneous ultraviolet exposure and development, resulting in well-defined AgI patterns. The sintering process successfully removed binders from the material layer and photoresist, yielding standalone AgI patterns on the Si substrate with good adhesion. The pitch remained consistent with the design values of the photomask when the pattern size was changed. In-situ observation of condensation frosting on the patterns was conducted, which confirmed the practicality of the developed patterning process. This versatile method is applicable to large areas with a high throughput and presents new opportunities for modifying functional surfaces.

This brief communication about machine perfusion of potential human donor hearts describes its historical development. Included in the review are both the isolated perfusion of donor hearts retrieved from heart beating and non-heart-beating donors. Additionally, some detail of in-situ (within the donor body) normothermic regional reperfusion of the heart and other organs is given. This only applies to the DCD donor heart. Similarly, some detail of ex-situ (outside the body) heart perfusion is offered. This article covers the entire history of the reperfusion of donor hearts. It takes us up to the current day describing 6 years follow-up of these donor machine perfused hearts. These clinical results appear similar to the outcomes of heart beating donors if reperfusion is managed within 30 min of normothermic circulatory determined death. Future developments are also offered. These are 3-fold and include: i. the pressing need for objective markers of the clinical outcome after transplantation, ii. the wish for isolated heart perfusion leading to improvement in donor heart quality, and iii. a strategy to safely lengthen the duration of isolated heart perfusion.

Western corn rootworm (WCR) is one of the most devastating corn rootworm species in North America because of its ability to cause severe production loss and grain quality damage. To control the loss, it is important to identify the infection of WCR at an early stage. Because the root system is the earliest feeding source of the WCR at the larvae stage, assessing the direct damage in the root system is crucial to achieving early detection. Most of the current methods still necessitate uprooting the entire plant, which could cause permanent destruction and a loss of the original root’s structural information. To measure the root damages caused by WCR non-destructively, this study utilized MISIRoot, a minimally invasive and in situ automatic plant root phenotyping robot to collect not only high-resolution images but also 3D positions of the roots without uprooting. To identify roots in the images and to study how the damages were distributed in different types of roots, a deep convolution neural network model was trained to differentiate the relatively thick and thin roots. In addition, a color camera was used to capture the above-ground morphological features, such as the leaf color, plant height, and side-view leaf area. To check if the plant shoot had any visible symptoms in the inoculated group compared to the control group, several vegetation indices were calculated based on the RGB color. Additionally, the shoot morphological features were fed into a PLS-DA model to differentiate the two groups. Results showed that none of the above-ground features or models output a statistically significant difference between the two groups at the 95% confidence level. On the contrary, many of the root structural features measured using MISIRoot could successfully differentiate the two groups with the smallest t-test p-value of 1.5791 × 10−6. The promising outcomes were solid proof of the effectiveness of MISIRoot as a potential solution for identifying WCR infestations before the plant shoot showed significant symptoms.

Metal–organic frameworks (MOFs) are highly nanostructured coordination polymers that contain metal cations and organic linkers and feature very large pore volumes and surface areas. The sorption and desorption of n-pentane vapor by porphyrin aluminum metal–organic framework Al-MOF-TCPPH2 where TCPPH2 is tetrakis(4-carboxyphenyl)porphyrin linker were studied by a novel method of in-situ time-dependent attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy in a controlled atmosphere and complementary in-situ and ex-situ methods. Sorption facilely occurs in the flow of dried air, and in the obtained adsorption complex the adsorbate molecules interact with phenyl and carboxylate groups of the linker and the O-H group. Sorption kinetics follows the pseudo-first-order rate law, as confirmed by in-situ time-dependent gravimetry. Further, an ex-situ (static) sorption of n-pentane vapor results in an adsorption complex with as much as 29.1 wt.% n-pentane with the stoichiometric formula [Al-MOF-TCPPH2]2(n-C5H12)7 and a distinct XRD pattern. Finally, in the flow of dried air, the adsorption complex gradually desorbed n-pentane, following the pseudo-first-order rate law. The reversibility of sorption and desorption makes porphyrin aluminum MOF promising for the separation of light hydrocarbons and chemo-sensing. In-situ time-dependent ATR-FTIR spectroscopy in a controlled atmosphere, in combination with in-situ time-dependent gravimetry, is a new approach for the determination of binding sites of sorbents with adsorbate molecules, the stoichiometry of complexes, and chemical kinetics of “solid–gas” interactions.

This work investigates the effects of oxygen and humidity on black phosphorous (BP) and black arsenic phosphorous (AsxP1−x ) flakes using Raman spectroscopy and in situ electric transport measurements (four-probe resistance and thermoelectric power, TEP). The results show that the incorporation of arsenic into the lattice of BP renders it more stable, with the degradation times for BP, As0.2P0.8, and As0.4P0.6 being 4, 5, and 11 days, respectively. The P-P Raman peak intensities were determined to decrease with exposure to oxygen and moisture. The TEP measurements confirmed that both BP and AsxP1−x are p-type semiconductors with the TEP of As0.4P0.6 stabilizing more slowly than that of BP. In addition, the four-probe resistance of BP and AsxP1−x stabilized significantly faster when exposed to air after being degassed in a vacuum. This was attributed to the charge transfer between the oxygen redox potential of air and the Fermi energy (EF) of the semiconductors.

Soil moisture is an essential hydrological variable for a suite of hydrological applications. Its spatio-temporal variability can be estimated using satellite remote sensing (e.g., SMOS and SMAP) and in-situ measurements. However, both have their own strengths and limitations. For example, remote sensing has the strength of maintaining the spatial variability of near-surface soil moisture, while in-situ measurements are accurate and preserve the dynamics range of soil moisture at both surface and larger depths. Hence, this study is aimed at (1) merging the strength of SMAP with in-situ measurements and (2) exploring the effectiveness of merged SMAP/in-situ soil moisture in improving ensemble streamflow forecasts. The conditional merging technique was adopted to merge the SMAP-enhanced soil moisture (9 km) and its downscaled version (1 km) separately with the in-situ soil moisture collected over the au Saumon watershed, a 1025 km2 watershed located in Eastern Canada. The random forest machine learning technique was used for downscaling of the near-surface SMAP-enhanced soil moisture to 1 km resolution, whereas the exponential filter was used for vertical extrapolation of the SMAP near-surface soil moisture. A simple data assimilation technique known as direct insertion was used to update the topsoil layer of a physically-based distributed hydrological model with four soil moisture products: (1) the merged SMAP/in-situ soil moisture at 9 and 1 km resolutions; (2) the original SMAP-enhanced (9 km), (3) downscaled SMAP-enhanced (1 km), and (4) interpolated in-situ surface soil moisture. In addition, the vertically extrapolated merged SMAP/in-situ soil moisture and subsurface (rootzone) in-situ soil moisture were used to update the intermediate layer of the model. Results indicate that downscaling of the SMAP-enhanced soil moisture to 1 km resolution improved the spatial variability of soil moisture while maintaining the spatial pattern of its original counterpart. Similarly, merging of the SMAP with in- situ soil moisture preserved the dynamic range of in-situ soil moisture and maintained the spatial heterogeneity of SMAP soil moisture. Updating of the top layer of the model with the 1 km merged SMAP/in-situ soil moisture improved the ensemble streamflow forecast compared to the model updated with either the SMAP-enhanced or in-situ soil moisture alone. On the other hand, updating the top and intermediate layers of the model with surface and vertically extrapolated SMAP/in-situ soil moisture, respectively, did not further improve the accuracy of the ensemble streamflow forecast. Overall, this study demonstrated the potential of merging the SMAP and in-situ soil moisture for streamflow forecast.

Microscopic strain and strain-induced phase transformation during plastic deformation in metastable austenitic steel were investigated at different strain rates. Quasi in-situ tension tests were performed sequentially with well-defined elongation intervals at room temperature at strain rates of 10−3 s−1 and 10−1 s−1. The tests were monitored by high-resolution optical imaging with a microscopic lens at a resolution of 0.23 µm/pixel. The macroscopic temperature was also measured with an infrared (IR) camera. The microstructure-level strain localizations were observed on the surface of the etched specimens by means of microscale digital image correlation (µDIC). Additionally, the microstructure was characterized by electron backscatter diffraction (EBSD) at the same location before and after deformation. The results of the study indicated that microscopic strain localizations favored the formation of α′-martensite particles. At the lower strain rate, high local strain concentrations formed at several locations in the microstructure, correlating with the areas where the formation of large martensite islands occurred. Martensite particles of various sizes formed nearby each other at the lower strain rate, whereas at the higher strain rate, martensite islands remained small and isolated. Although the macroscopic increase in temperature at both the studied strain rates was very low, at the higher strain rate, local heating on the microscopic scale could take place at the newly nucleated martensite embryos. This inhibited the further growth of the martensite particles, and local strain distribution also remained more homogeneous than at the lower strain rate.

The determination of the load bearing capacity of masonry in existing structures is not an easy task, even for experienced surveyors. For its assessment, it is necessary to know the compressive strength of the masonry units and mortar. Relatively good destructive and non-destructive methods were developed for the determination of the compressive strength of masonry units. However, mortar compressive strength determination is currently closer to a rough estimation rather than a deterministic approach. All of the currently used methods are either complicated, have a limited application, or are based on the surveyor’s experience only. Influence of the human factor on the results of testing is significant. The paper introduces the development of a new non-destructive method, which eliminates the influence of the human factor. The method is supposed to work as quickly and as easily as the Schmidt hammer used for concrete structure surveys. The new instrument was created where the compressive strength of mortar is assessed by hammering a steel bar into a joint with constant energy, while the depth of penetration is measured. The impact energy is provided by a steel spring with a prescribed stiffness, and the loading is provided by an automatic system similar to those used in air-soft guns.

This work analyses damage formation within the bulk of basalt fiber-reinforced polymers (BFRP) by means of open-source Digital Volume Correlation (DVC). Volumetric image data were obtained from conventional in-situ X-Ray computed micro-tomography (µCT) of samples loaded in tension. The open-source image registration toolkit Elastix was employed to obtain full 3D displacement fields from the image data. We assessed the accuracy of the DVC results using the method of manufactured solution and showed that the approach followed here can detect deformation with a magnitude in the order of a fiber diameter which in the present case is 17 µm. The beneficial influence of regularization on DVC results is presented on the manufactured solution as well as on real in-situ tensile testing CT data of a BFRP sample. Results of the correlation showed that conventional µCT equipment in combination with DVC can be used to detect defects which could previously only be visualized using synchrotron facilities or destructive methods.

Laser-based thermoplastic automated fiber placement (TAFP) is nowadays mainly used to produce pure carbon fiber-reinforced plastic (CFRP) structures. This paper investigates the feasibility of a novel application: The deposition of thermoplastic prepreg tapes onto a thermoplastic foam for the production of thermoplastic sandwich structures. Therefore, simple deposition experiments of thermoplastic PEEK/CF prepreg tapes on a PEI closed-cell foam were carried out. 3D surface profile measurements and peel tests according to DIN EN 28510-1 standard were used to investigate the joining area and bonding quality. The results show that a cohesive bond is formed between the deposited tapes and the foam core, however the foam structure in the area of the deposited tapes deforms in dependence of the process parameters, and increasingly with higher deposition temperatures. Due to the deformations that occur during tape deposition, the thermomechanical foam behavior under the TAFP process conditions was investigated in more detail in a subsequent study for an extensive parameter space using a simple experimental setup. Results show that for suitable process parameters, namely a short contact time and a high temperature, the foam deformation can be minimized with the simultaneous formation of a thin melting layer required for cohesive bonding. The inner foam core structure remains unaffected.

In this paper, five groups of industrial aluminium back-surface-field (Al-BSF) solar cells were made from silicon wafers from different locations of a B-doped Czochralski silicon ingot. Then, we performed the first LID (45 °C, 1 sun, 12 h), regeneration (100 °C, 1 sun, 24 h), and second LID (45 °C, 1 sun, 12 h) treatments on the cells, and measured the in-situ changes of their I-V characteristic parameters by using an I-V tester during the experiment. The cells were also characterized by Suns-Voc measurement, full-area light beam induced current scanning, and external quantum efficiency measurement at the four breakpoints of treatments (before and after the first LID, after regeneration and the second LID). It was found that the LID and regeneration of the Al-BSF solar cells can be explained by the LID and regeneration reaction of B-O defects and the LID caused by dissociation of Fe-B pairs. After regeneration, the relative decay rate of efficiency decreased from 2.75–3.8% during the first LID to 0.42–1.23% during the second LID, indicating that regeneration treatment (100 °C, 1 sun, 24 h) can improve the anti-LID ability of Al-BSF solar cells.

A novel technique for the in situ removal of mineral hydrocarbons from aged brownfields is described. The approach uses emulsions of plant oil (5–10%, rapeseed) in water, which were found to extract 50–85% of mineral hydrocarbons in one leaching step from the non-saturated zone. The emulsion was allowed to travel though the ground and was pumped off from the groundwater level. Approximately 15–50% of the plant oil stayed in the soil. By flushing the area with water afterwards, that amount can be reduced to 10–30%, and in some cases to 3 of water were sent over a pilot installation for oil/water separation using non-wovens. A slightly better separation performance than by oil separators was observed. This process has the potential to be combined with a regular oil separator to allow water purification to a level at which it can be reintroduced into the ground. The technique was tested on a brownfield in Lower Austria, a former refinery site abandoned approx. 80 years ago with a peak hydrocarbon contamination of 40,000 mg/kg of dry soil and free-floating mineral oil on the groundwater level. Since in situ techniques can be more environmentally benign and less costly than traditional remediation approaches, this novel approach holds an interesting potential, which could be proven at a technology readiness level (TRL) of 5.

In-situ forming implants (ISFIs) represent a simple, tunable, and biodegradable polymer-based platform for long-acting drug delivery. However, drugs with different physicochemical properties and physical states in the polymer-solvent system exhibit different drug release kinetics. Although a few limited studies have been performed attempting to elucidate these effects, a large, systematic study has not been performed until now. The purpose of this study was to characterize the in vitro drug release of 12 different small molecule drugs with differing logP and pKa values from ISFIs. Drug release was compared with polymer degradation as measured by lactic acid (LA) release and change in poly(DL-lactide-co-glycolide) (PLGA) molecular weight (MW) measured by size exclusion chromatography with multi-angle laser light scattering (SEC-MALS). Drug physical state and morphology were also measured using differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Together, these results demonstrated that hydrophilic drugs have higher burst release at 24 h (22.8–68.4%) and complete drug release within 60 days, while hydrophobic drugs have lower burst release at 24 h (1.8–18.9%) and can sustain drug release over 60–285 days. Overall, drug logP and drug physical state in the polymer–solvent system are the most important factors when predicting the drug release rate in an ISFI for small-molecule drugs. Hydrophilic drugs exhibit high initial burst and less sustained release due to their miscibility with the aqueous phase, while hydrophobic drugs have lower initial burst and more sustained release due to their affinity for the hydrophobic PLGA. Additionally, while hydrophilic drugs seem to accelerate the degradation of PLGA, hydrophobic drugs on the other hand seem to slow down the PLGA degradation process compared with placebo ISFIs. Furthermore, drugs that were in a crystalline state within the ISFI drugs exhibited more sustained release compared with amorphous drugs.

The present research uses in-situ neutron diffraction to examine the effect of grain refinement on grain growth during solidification of Al-5 wt.% Cu and Mg-5 wt.% Zn alloys. The alloys were grain refined through additions of Al-5Ti-1B and Zr, respectively. The in-situ neutron diffraction experiments were carried out by heating the alloys to temperatures above the liquidus and subsequently cooling in 5 or 10 °C temperature steps to temperatures below solidus, while being irradiated by thermal neutrons. With the addition of grain refiners, grain size reductions of 92% were observed for both the Al-5 wt.% Cu and Mg-5 wt.% Zn alloys. The refined and unrefined Al-5 wt.% Cu alloys contained α-Al with Al2Cu along the grain boundary regions. Differences in Al2Cu morphology were observed in the grain refined alloys. The Mg-5 wt.% Zn alloy contained MgZn intermetallic phases with primary Mg. The refined Mg-5 wt.% Zn-0.7 wt.% Zr alloy contained Mg, MgZn and Zn2Zr phases. In-situ neutron diffraction enabled quantification of individual plane solid fraction growth for the α-Al and Al2Cu phases in the Al-Cu alloys, and for α-Mg in the Mg alloys. For the unrefined Al-5 wt.% Cu, the coarse microstructure resulted in a rapid solid fraction rise at temperatures just below liquidus followed by a gradual increase in solid fraction until the sample was fully solid. The grain-refined Al-5 wt.% Cu alloys showed a columnar to equiaxed microstructure transition and a more gradual growth in fraction solid throughout solidification. For the Mg-5 wt.% Zn alloy, the more packed (0002) and (101¯1) α-Mg plane intensities grew at a slower rate than the (101¯0) plane intensity, resulting in an irregular grain structure. With the addition of the Zr grain refiner, the Mg-5 wt.% Zn-0.7 wt.% Zr alloy had (101¯0), (0002) and (101¯1) planes intensities all increasing at similar rates, especially at the early stages of solidification. FactSage™ (version 6.4, Montréal, QC, Canada) equilibrium solidification models followed the fraction solid curves developed by tracking the fastest growing planes of the Mg alloys.

This article discusses the assessment of groundwater quality using a hybrid technique that would aid in the convenience of groundwater (GW) quality monitoring. Twenty eight (28) GW samples representing 62 barangays in Calapan City, Oriental Mindoro, Philippines were analyzed for their physicochemical characteristics and heavy metal (HM) concentrations. The 28 GW samples were collected at suburban sites identified by the coordinates produced by Global Positioning System Montana 680. The analysis of heavy metal concentrations was conducted onsite using portable handheld X-Ray Fluorescence (pXRF) Spectrometry. Hybrid machine learning—geostatistical interpolation (MLGI) method, specific to neural network particle swarm optimization with Empirical Bayesian Kriging (NN-PSO+EBK), was employed for data integration, GW quality spatial assessment and monitoring. Spatial map of metals concentration was produced using the NN-PSO-EBK. Another, spot map was created for observed metals concentration and was compared to the spatial maps. Results showed that the created maps recorded significant results based on its MSEs with values such as 1.404 × 10−4, 5.42 × 10−5, 6.26 × 10−4, 3.7 × 10−6, 4.141 × 10−4 for Ba, Cu, Fe, Mn, Zn, respectively. Also, cross-validation of the observed and predicted values resulted to R values range within 0.934–0.994 which means almost accurate. Based on these results, it can be stated that the technique is efficient for groundwater quality monitoring. Utilization of this technique could be useful in regular and efficient GW quality monitoring.

In this study, we submit a complex set of in-situ data collected by optical emission spectroscopy (OES) during the process of aluminum nitride (AlN) thin film. Changing the sputtering power and nitrogen(N2) flow rate, AlN film was deposited on Si substrate using a superior sputtering with a pulsed direct current (DC) method. The correlation between OES data and deposited film residual stress (tensile vs. compressive) associated with crystalline status by X-ray diffraction spectroscopy (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) measurements were investigated and established throughout the machine learning exercise. An important answer to know is whether the stress of the processing film is compressive or tensile. To answer this question, we can access as many optical spectra data as we need, record the data to generate a library, and exploit principal component analysis (PCA) to reduce complexity from complex data. After preprocessing through PCA, we demonstrated that we could apply standard artificial neural networks (ANNs), and we could obtain a machine learning classification method to distinguish the stress types of the AlN thin films obtained by analyzing XRD results and correlating with TEM microstructures. Combining PCA with ANNs, an accurate method for in-situ stress prediction and classification was created to solve the semiconductor process problems related to film property on deposited films more efficiently. Therefore, methods for machine learning-assisted classification can be further extended and applied to other semiconductors or related research of interest in the future.

In this work, the composition, structural and morphological features, and particle size of the active phase of the catalyst (MoS2), synthesized in-situ during the heavy oil hydroconversion performed in continuous flow reactor on lab-scale pilot flow unit at T = 450 °C, P = 6.0–9.0 MPa, V = 1.0 h−1, H2/feed = 1000 nL/L, catalyst concentration C (Mo) = 0.01–0.08%wt have been studied. It has been shown that MoS2 formed during hydroconversion is represented by nanosized particles stabilized by polycondensation products as a result of strong adsorption and aggregation with the components of the hydroconversion reaction medium. The influence of morphological characteristics of catalyst nanoparticles on the feed conversion, the yield of gaseous and liquid products, and the quality of distillate fractions, as well as the yield of polycondensation products, have been studied. It has been established that an increase in MoS2 active site dispersion, both due to a decreased plate length and lower stacking numbers in MoS2 cluster, enhances hydroconversion effectivity, particularly, in suppressing polycondensation reactions.

This study introduces an innovative photolithography-based method for patterning ionic and inorganic particle materials such as silver iodide (AgI). Conventional methods lack precision when patterning powdered materials, which limits their applicability. The proposed method stacks layers of a particle material (AgI) and negative-tone photoresist for simultaneous ultraviolet exposure and development, resulting in well-defined AgI patterns. The sintering process successfully removed binders from the material layer and photoresist, yielding standalone AgI patterns on the Si substrate with good adhesion. The pitch remained consistent with the design values of the photomask when the pattern size was changed. In-situ observation of condensation frosting on the patterns was conducted, which confirmed the practicality of the developed patterning process. This versatile method is applicable to large areas with a high throughput and presents new opportunities for modifying functional surfaces.

In this study, the contamination of H+ZSM-5 catalyst by calcium, potassium and sodium was investigated by deactivating the catalyst with various concentrations of these inorganics, and the subsequent changes in the properties of the catalyst are reported. Specific surface area analysis of the catalysts revealed a progressive reduction with increasing concentrations of the inorganics, which could be attributed to pore blocking and diffusion resistance. Chemisorption studies (NH3-TPD) showed that the Bronsted acid sites on the catalyst had reacted with potassium and sodium, resulting in a clear loss of active sites, whereas the presence of calcium did not appear to cause extensive chemical deactivation. Pyrolysis experiments revealed the progressive loss in catalytic activity, evident due the shift in selectivity from producing only aromatic hydrocarbons (benzene, toluene, xylene, naphthalenes and others) with the fresh catalyst to oxygenated compounds such as phenols, guaiacols, furans and ketones with increasing contamination by the inorganics. The carbon yield of aromatic hydrocarbons decreased from 22.3% with the fresh catalyst to 1.4% and 2.1% when deactivated by potassium and sodium at 2 wt %, respectively. However, calcium appears to only cause physical deactivation.

The transient nature of the internal pore structure of particulate wall flow filters, caused by the continuous deposition of particulate matter, makes studying their flow and filtration characteristics challenging. In this article we present a new methodology and first experimental demonstration of time resolved in-situ synchrotron micro X-ray computed tomography (micro-CT) to study aerosol filtration. We directly imaged in 4D (3D plus time) pore scale deposits of TiO2 nanoparticles (nominal mean primary diameter of 25 nm) with a pixel resolution of 1.6 μm. We obtained 3D tomograms at a rate of ∼1 per minute. The combined spatial and temporal resolution allows us to observe pore blocking and filling phenomena as they occur in the filter’s pore space. We quantified the reduction in filter porosity over time, from an initial porosity of 0.60 to a final porosity of 0.56 after 20 min. Furthermore, the penetration depth of particulate deposits and filtration rate was quantified. This novel image-based method offers valuable and statistically relevant insights into how the pore structure and function evolves during particulate filtration. Our data set will allow validation of simulations of automotive wall flow filters. Evolutions of this experimental design have potential for the study of a wide range of dry aerosol filters and could be directly applied to catalysed automotive wall flow filters.

An improved understanding of the malting process could have a significant impact on the efficient production of quality malt for the brewing industry. Analysis of volatile organic compounds produced during the malting process is one approach towards achieving this goal. In-situ methods avoid the possibility of contamination and chemical changes occurring during sample transport and storage. This paper describes the investigation of an in-situ sampling method for the detection of volatile organic compounds produced during the malting of barley. Solid Phase Microextraction Gas Chromatography Mass Spectrometry (SPME-GC/MS) was used to identify compounds. The investigated method involved the direct exposure of an SPME fiber in the kiln during barley malting. Using this method, compounds including aldehydes, ketones, and esters were detected. Some changes in volatile organic compound composition were observed during the production of pale malt at a commercial malting house.

In order to improve the high temperature oxidation resistance of Ti6Al4V alloy, the in-situ TiN-Ti composite coatings were prepared with Ti-Cr-Ni-Nb powders by plasma transferred arc welding. Nitrogen gas was used as the transport gas and provided N source for the formation reaction of TiN. Microstructure features and high temperature oxidation behaviors of the composite coatings were studied. The phases in the composite coatings were TiN, Ti, CrN, and NiTi. It was clearly observed that in-situ TiN particles were evenly distributed in the Ti matrix. A little Nb atom dissolved in TiN particles, and others dissolved in the Ti matrix. By comparing the curve of Ti6Al4V alloy to that of the composite coatings, the oxidation mass gain of the composite coatings was comparatively less. The oxidation film of the composite coatings was smooth and compact, and no crack was visibly observed. Based on the results of the high temperature tests, the composite coatings exhibited superior high temperature oxidation resistance than Ti6Al4V alloy both at 650 °C and at 850 °C.

Magnesium alloys are primarily associated with complex forming mechanisms, which yield ductility at high temperatures. In sheet metal forming, high triaxiality stress states that favor the ductile damage mechanisms of void formation and growth are known to malleable metals. The formulation of coupled damage models has so far failed, due to the incomplete experimental determination of damage parameters for magnesium AZ31 thin sheet. A quantitative investigation was conducted to determine the ductile damage behavior of twin-roll cast, hot rolled, and annealed AZ31 thin sheet. Results on the mechanisms of void nucleation-, coalescence- and growth-rate were established at temperatures ranging from room temperature to 350 °C. In-situ tensile tests were carried out in a scanning electron microscope with three different specimen types: Simple tension specimens, notched specimens for high triaxiality stress state testing, and shear specimens. Through a comparative analysis of local strains measured by digital image correlation and local void volume fractions determined through post-mortem analysis of specimen cross-sections, GTN (Gurson–Tvergaard–Needleman) model-based material parameters were determined by experiment, representing a novel departure in the magnesium research landscape. The procedure developed in this context should also be transferable to other metals in the form of thin sheets.

Investigation of biofilms and visualization using non-destructive imaging techniques like X-ray μCT has recently gained interest. Biofilms are congregations of microorganisms that attach to surfaces and comprise of microbial cells embedded in extracellular polymeric substances (EPS). They are ubiquitous entities that are commonly found in any non-sterile setting and have direct implications on human health. Methods to visualize them in-situ are highly needed to understand their behaviour (attachment and detachment) inside a substrate. Contrast-enhanced X-ray μCT is a 3D imaging technique that is capable of visualising objects that have very low attenuation contrast. The use of contrast agents in X-ray μCT has been an evolving process, however, the possible toxic effect of these chemical compounds against biofilms has not been studied in detail. In this study, we focus on the toxic effect of contrast agents and study the diffusion and drainage of contrast agents in biofilms. We propose using water-soluble potassium bromide (KBr) as a suitable contrast agent for enhancement of the attenuation coefficient of a monoculture of Pseudomonas fluorescens biofilms inside a porous substrate. At the given concentration, KBr proved to be less bactericidal compared to other commonly used contrast agents and at 5% w/v concentration we were able to clearly distinguish between the biofilm and the porous substrate.

In the present study, plasma spray welding was used to prepare an in-situ niobium carbide (NbC) reinforced Ni-based composite coating on the low carbon steel, and the phase composition and the microstructure of the composite coatings were studied. The wear resistance and the wear mechanism of the composite coatings were also researched by the wear tests. The results showed that the main phases of the composite coating were NbC, γ-Ni, Cr23C6, Ni3Si, CrB, Cr5B3, Cr7C3 and FeNi3. A number of fine in-situ NbC particles and numerous chromium carbide particles were distributed in the γ-Ni matrix. The increase in the mass fraction of Nb and NiCr-Cr3C2 could lead to the increase in NbC particles in the composite coatings. Due to the high hardness of NbC and chromium carbides, the micro-hardness and the wear resistance of the composite coatings were advanced. The composite coating with the powder mixtures of 20% (Nb + NiCr-Cr3C2) and 80% NiCrBSi had the highest micro-hardness and the best wear resistance in this study. The average micro-hardness reached the maximum value 1025HV0.5. The volume loss was 39.2 mm3, which was merely 37% of that of the NiCrBSi coating and 6% of that of the substrate under the identical conditions.

Thermosetting polymers have been widely used in many industrial applications as adhesives, coatings and laminated materials, among others. Recently, bisphenol A (BPA) has been banned as raw material for polymeric products, due to its harmful impact on human health. On the other hand, the use of aromatic amines as curing agents confers excellent thermal, mechanical and flame retardant properties to the final product, although they are toxic and subject to governmental restrictions. In this context, sugar-derived diepoxy monomers and anhydrides represent a sustainable greener alternative to BPA and aromatic amines. Herein, we report an “in-situ” sol–gel synthesis, using as precursors tetraethylorthosilicate (TEOS) and aminopropyl triethoxysilane (APTS) to obtain bio-based epoxy/silica composites; in a first step, the APTS was left to react with 2,5-bis[(oxyran-2-ylmethoxy)methyl]furan (BOMF) or diglycidyl ether of bisphenol A (DGEBA)monomers, and silica particles were generated in the epoxy in a second step; both systems were cured with methyl nadic anhydride (MNA). Morphological investigation of the composites through transmission electron microscopy (TEM) demonstrated that the hybrid strategy allows a very fine distribution of silica nanoparticles (at nanometric level) to be achieved within a hybrid network structure for both the diepoxy monomers. Concerning the fire behavior, as assessed in vertical flame spread tests, the use of anhydride curing agent prevented melt dripping phenomena and provided high char-forming character to the bio-based epoxy systems and their phenyl analog. In addition, forced combustion tests showed that the use of anhydride hardener instead of aliphatic polyamine results in a remarkable decrease of heat release rate. An overall decrease of the smoke parameters, which is highly desirable in a context of greater fire safety was observed in the case of BOMF/MNA system. The experimental results suggest that the effect of silica nanoparticles on fire behavior appears to be related to their dispersion degree.

A versatile and straightforward route to produce polymer foams with functional surface through their decoration with gold and palladium nanoparticles is proposed. Melamine foams, used as polymeric porous substrates, are first covered with a uniform coating of polydimethylsiloxane, thin enough to assure the preservation of their original porous structure. The polydimethylsiloxane layer allows the facile in-situ formation of metallic Au and Pd nanoparticles with sizes of tens of nanometers directly on the surface of the struts of the foam by the direct immersion of the foams into gold or palladium precursor solutions. The effect of the gold and palladium precursor concentration, as well as the reaction time with the foams, to the amount and sizes of the nanoparticles synthesized on the foams, was studied and the ideal conditions for an optimized functionalization were defined. Gold and palladium contents of about 1 wt.% were achieved, while the nanoparticles were proven to be stably adhered to the foam, avoiding potential risks related to their accidental release.

Here we explore and review some of the latest ideas and applications of Raman spectroscopy to the volcanological sciences. Firstly, we provide a brief overview of how Raman spectral analysis works and how spectra from silicate glasses are interpreted. We then look at specific applications of Raman spectral analysis to the volcanological sciences based on measurements on and studies of natural materials in the laboratory. We conclude by examining the potential for Raman spectral analysis to be used as a field based aid to volcano monitoring via in situ studies of proximal deposits and; perhaps; in remote sensing campaigns

This paper introduces a three-dimensional (3D) pyramid to the polymers-plasmonic hybrid structure of polymethyl methacrylate (PMMA) composite silver nanoparticle (AgNPs) as a higher quality flexible surface-enhanced Raman scattering (SERS) substrate. Benefiting from the effective oscillation of light inside the pyramid valley could provide wide distributions of 3D “hot spots” in a large space. The inclined surface design of the pyramid structure could facilitate the aggregation of probe molecules, which achieves highly sensitive detection of rhodamine 6G (R6G) and crystal violet (CV). In addition, the AgNPs and PMMA composite structures provide uniform space distribution for analyte detection in a designated hot spot zone. The incident light can penetrate the external PMMA film to trigger the localized plasmon resonance of the encapsulated AgNPs, achieving enormous enhancement factor (~ 6.24 × 10 8 ). After undergoes mechanical deformation, the flexible SERS substrate still maintains high mechanical stability, which was proved by experiment and theory. For practical applications, the prepared flexible SERS substrate is adapted to the in-situ Raman detection of adenosine aqueous solution and the methylene-blue (MB) molecule detection of the skin of a fish, providing a direct and nondestructive active-platform for the detecting on the surfaces with any arbitrary morphology and aqueous solution.

We developed a stress sensor for in-situ deformation experiments using synchrotron radial X-ray diffraction. This stress sensor provided nearly diffraction-plane-independent stress that, when used in series with a sample, reduced the uncertainty of the average stress estimation acting on a sample. Here, we present the results of a study where pyrope was used as a stress sensor. Using a Deformation-DIA (D-DIA) high-pressure deformation apparatus, pyrope, olivine and alumina were deformed in the same run/cell assembly placed in series along the compression direction. Deformation experiments were conducted at pressures between 4 and 5 GPa and temperatures between 730 and 1273 K with strain-rates between 10−5 and 10−6 s−1. Stresses estimated from various (hkl) planes in pyrope were nearly the same; i.e., pyrope is plastically isotropic with ≤10 % variation with (hkl). However, stresses from various (hkl) planes in olivine and alumina varied by approximately a factor of 3. Comparisons between average stresses inferred from pyrope and those from different diffraction planes in olivine and alumina showed that the average stress in these materials evolved from low-end stress, estimated from various (hkl) planes at small strain, to high-end stress at a large strain. This suggests that the rate-controlling slip system in these materials changes from the soft to the hard slip system with strain.

Valeriana wallichii, a perennial herb belonging to family Valerianaceae, is an important medicinal herb of the Himalayan region. The incessant exploitation of nature for meeting the demands of the pharmaceutical industry has put unbearable pressure on its natural habitats. A study on its physiological, biochemical, growth and reproductive attributes was planned. Physiological study revealed that ex-situ (outside their natural habitat) populations faced severe stress as compared to in-situ (natural habitat) plants. The difference in the performance of these habitat plants was related to superoxide and H2O2 in the leaves. Photosynthetic attributes were increased in in-situ populations. Proline content and its biosynthetic enzymes ornithine aminotransferase, and pyrroline-5-carboxylate reductase showed an increase in ex-situ plants; proline oxidase decreased. Glucose-6-phosphate dehydrogenase, shikimic acid dehydrogenese, phenylalanine lyase, and flavonoids content showed an increment in ex-situ plants. Antioxidants enzyme superoxide dismutase, catalase, ascorbate peroxidase and reduced glutathione showed an increment in ex-situ conditions. Growth and reproductive attributes were more in ex-situ plants. The observations made are suggestive that a comprehensive conservation programme involving in-situ as well as ex-situ strategies will be effective for the conservation and long term survival of the species.

This paper develops an array micro-grooves manufacturing method using micro electrochemical machining (ECM) with disk electrode, which is prepared by in-situ micro wire electrical discharge machining (WEDM). This technology focuses on the difficulty of array structure manufacture in micro-electro-mechanical systems (MEMS). A micro-ECM system is built based on the micro-WEDM machine to achieve high precision processing of the array micro-grooves. Since micro-WEDM has good performance in high precision machining of the rotating structure, single and multi-edge disk electrodes can be fabricated in-situ using graphite. The as-prepared disk tool electrode is directly used for micro-electrochemical milling of the array micro-grooves without disassembling away from the device, which avoids the positioning error caused by the re-clamping of the disk electrode. With the advantages of high surface quality and no electrode loss, micro-ECM improves the manufacture performance of the micro-parts. Through wire path optimization, the shape accuracy of the disk edge is improved. After the research of the micro-ECM parameters, the process is improved, and finally, the high precision array micro-grooves are obtained. This method combines the advantages of micro-WEDM and disk electrode micro-ECM milling, and it is convenient for large-scale manufacture of array micro-structures on micro-parts and MEMS.

Magnesium borohydride (Mg(BH4)2) is one of the most promising hydrogen storage materials. Its kinetics of hydrogen desorption, reversibility, and complex reaction pathways during decomposition and rehydrogenation, however, present a challenge, which has been often addressed by using transition metal compounds as additives. In this work the decomposition of Mg(BH4)2 ball-milled with CoCl2 and CoF2 additives, was studied by means of a combination of several in-situ techniques. Synchrotron X-ray diffraction and Raman spectroscopy were used to follow the phase transitions and decomposition of Mg(BH4)2. By comparison with pure milled Mg(BH4)2, the temperature for the γ → ε phase transition in the samples with CoF2 or CoCl2 additives was reduced by 10–45 °C. In-situ Raman measurements showed the formation of a decomposition phase with vibrations at 2513, 2411 and 766 cm−1 in the sample with CoF2. Simultaneous X-ray absorption measurements at the Co K-edge revealed that the additives chemically transformed to other species. CoF2 slowly reacted upon heating till ~290 °C, whereas CoCl2 transformed drastically at ~180 °C.

Continuous measurement systems are widely spread in sewers, especially in non-pressure systems. Due to its relatively low costs, turbidity sensors are often used as a surrogate for other indicators (solids, heavy metals, organic compounds). However, little effort is spent to turbidity sensors in pressurized systems so far. This work presents the results of one year in-situ turbidity/total suspended solids (TSS) monitoring inside a pressure pipe (600 mm diameter) in an urban region in northern Germany. The high-resolution sensor data (5 s interval) are used for the determination of solids sedimentation (within pump pauses) and erosion behavior (within pump sequences). In-situ results from sensor measurements are similar to laboratory results presented in previous studies. TSS is decreasing exponentially in pump pauses under dry weather inflow with an average of 0.23 mg/(L s). During pump sequences, solids eroded completely at a bed shear stress of 0.5 N/m². Sedimentation and erosion behavior changes with the inflow rate. Solids settle faster with increasing inflow: at storm water inflow with an average of 0.9 mg/(L s) and at diurnal inflow variation up to 0.6 mg/(L s) at 12:00 a.m. The results are used as calibration data for a sediment transport simulation in Part II.

Biodiversity is rapidly decreasing worldwide. Its great importance has been attached to conservation through in-situ and ex-situ management. Animal-mediated seed dispersal is an important ecological process, linking the threatened plants and animal partners in ex-situ habitats, and in turn affecting tree conservation. However, how bird traits affect seed dispersal within in-situ and ex-situ conservation still remains unclear. Here, we aim to answer this question. We tested whether bird traits affect seed deposition and seedling recruitment. Our results showed that 19 bird species foraged and removed Taxus chinensis (Pilger) Rehd. seeds across botanical gardens (ex-situ) and natural reserves (in-situ). The seed dispersal pattern of T. chinensis varied in the stages of seed removal and seed deposition, but showed no significant difference in the seedling recruitment stage. This showed that bird morphological and behavioral traits affected seed dispersal through the different contributions of varying bird species. Large birds and their high visitation frequency played a central role in seed removal patterns. The frequency of post-foraging habitat use was the most important factor determining the role of birds in seed deposition and the following seedling recruitment. Urocissa erythrorhyncha and Chloropsis hardwickii played the role of keystone species in seed deposition and seedling recruitment, respectively. Our results highlight the importance of bird traits in facilitating the seed dispersal of trees within in-situ and ex-situ conservation, which should be considered in future forest conservation and management.

Palladium can readily dissociate molecular hydrogen at its surface, and rapidly accept it onto the octahedral sites of its face-centered cubic crystal structure. This can include radioactive tritium. As tritium β-decays with a half-life of 12.3 years, He-3 is generated in the metal lattice, causing significant degradation of the material. Helium bubble evolution at high concentrations can result in blister formation or exfoliation and must therefore be well understood to predict the longevity of materials that absorb tritium. A hydrogen over-pressure must be applied to palladium hydride to prevent hydrogen from desorbing from the metal, making it difficult to study tritium in palladium by methods that involve vacuum, such as electron microscopy. Recent improvements in in-situ ion implantation Transmission Electron Microscopy (TEM) allow for the direct observation of He bubble nucleation and growth in materials. In this work, we present results from preliminary experiments using the new ion implantation Environmental TEM (ETEM) at the University of Huddersfield to observe He bubble nucleation and growth, in-situ, in palladium at cryogenic temperatures in a hydrogen environment. After the initial nucleation phase, bubble diameter remained constant throughout the implantation, but bubble density increased with implantation time. β-phase palladium hydride was not observed to form during the experiments, likely indicating that the cryogenic implantation temperature played a dominating role in the bubble nucleation and growth behavior.

Producing alloys via in-situ laser alloying approach is becoming very easy and a topical issue in the field of laser additive manufacturing. Several studies have emerged, accompanied by a statement by Gasper et al. (2017), who reported the economic benefits and cost savings that can be related to 3D printing of the additive manufacturing (AM) structure using the said in situ synthesis approach. They studied the laser in situ reactive synthesis of producing titanium aluminide (Ti−Al) from elemental powders using the laser materials deposition (LMD) process. This paper highlights how the functional grade Ti−Al alloys can be produced in a single flight using the 850-R Optomec Laser Engineering Net Shaping (LENS) system. The effects of the Al content in the as-built and heat-treated samples were investigated. The as-built samples were cracked, inhomogeneous, and had visible inter-layer boundaries due to the segregation of the alloying elements and different heat profiles that are typically experienced during 3D printing. These characteristics led to wavy hardness profiles. Heat-treated samples were the least hard when compared to the as-built samples and had a homogenized microstructure. Samples with a duplex microstructure were, in particular, the least hard, indicating that they would have better ductility than others. The outcomes of this study show that a structure with different composition can be fabricated with the LENS system. This would lead to adaptive structures being used, especially in the high temperature applications where a structure would have to withstand low and high temperatures during use.

Metal-organic frameworks (MOFs) are highly nanostructured coordination polymers that contain metal cations and organic linkers and feature very large pore volumes and surface areas. The sorption and desorption of n-pentane vapor by porphyrin aluminum metal-organic framework Al-MOF-TCPPH 2 where TCPPH 2 is tetrakis(4-carboxyphenyl)porphyrin linker were studied by a novel method of in-situ time-dependent attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy in a controlled atmosphere and complementary in-situ and ex-situ methods. Sorption facilely occurs in the flow of dried air, and in the obtained adsorption complex the adsorbate molecules interact with phenyl and carboxylate groups of the linker and the O-H group. Sorption kinetics follows the pseudo-first-order rate law, as confirmed by in-situ time-dependent gravimetry. Further, an ex-situ (static) sorption of n-pentane vapor results in an adsorption complex with as much as 29.1 wt.% n-pentane with the stoichiometric formula [Al-MOF-TCPPH 2 ] 2 (n-C 5 H 12 ) 7 and a distinct XRD pattern. Finally, in the flow of dried air, the adsorption complex gradually desorbed n-pentane, following the pseudo-first-order rate law. The reversibility of sorption and desorption makes porphyrin aluminum MOF promising for the separation of light hydrocarbons and chemo-sensing. In-situ time-dependent ATR-FTIR spectroscopy in a controlled atmosphere, in combination with in-situ time-dependent gravimetry, is a new approach for the determination of binding sites of sorbents with adsorbate molecules, the stoichiometry of complexes, and chemical kinetics of "solid-gas" interactions.

New approaches to collect in-situ data are needed to complement the high spatial (10 m) and temporal (5 d) resolution of Copernicus Sentinel satellite observations. Making sense of Sentinel observations requires high quality and timely in-situ data for training and validation. Classical ground truth collection is expensive, lacks scale, fails to exploit opportunities for automation, and is prone to sampling error. Here we evaluate the potential contribution of opportunistically exploiting crowdsourced street-level imagery to collect massive high-quality in-situ data in the context of crop monitoring. This study assesses this potential by answering two questions: (1) what is the spatial availability of these images across the European Union (EU), and (2) can these images be transformed to useful data? To answer the first question, we evaluated the EU availability of street-level images on Mapillary—the largest open-access platform for such images—against the Land Use and land Cover Area frame Survey (LUCAS) 2018, a systematic surveyed sampling of 337,031 points. For 37.78% of the LUCAS points a crowdsourced image is available within a 2 km buffer, with a mean distance of 816.11 m. We estimate that 9.44% of the EU territory has a crowdsourced image within 300 m from a LUCAS point, illustrating the huge potential of crowdsourcing as a complementary sampling tool. After artificial and built up (63.14%), and inland water (43.67%) land cover classes, arable land has the highest availability at 40.78%. To answer the second question, we focus on identifying crops at parcel level using all 13.6 million Mapillary images collected in the Netherlands. Only 1.9% of the contributors generated 75.15% of the images. A procedure was developed to select and harvest the pictures potentially best suited to identify crops using the geometries of 785,710 Dutch parcels and the pictures’ meta-data such as camera orientation and focal length. Availability of crowdsourced imagery looking at parcels was assessed for eight different crop groups with the 2017 parcel level declarations. Parcel revisits during the growing season allowed to track crop growth. Examples illustrate the capacity to recognize crops and their phenological development on crowdsourced street-level imagery. Consecutive images taken during the same capture track allow selecting the image with the best unobstructed view. In the future, dedicated crop capture tasks can improve image quality and expand coverage in rural areas.

Due to the increasing ease of use and the superiority of the results, distributed strain measurements, utilizing Optical Backscatter Reflectometry (OBR), have become more important and widespread over the last few years. Strains are calculated from the difference between an actual optical Raleigh backscattering measurement and an initial reference value. However, under certain physical conditions, e.g., pinching or microbending of the optical fiber, no meaningful strain values are yielded by the commonly-used method to analyze OBR data. Such conditions were experienced in this study where the optical fiber was embedded into hardening epoxy for measuring shrinkage due to curing. In this work, it is shown that a new data analysis method called the “running reference analysis method” can overcome such obstacles and deliver meaningful strain values in circumstances in which the traditional method fails. In the new approach, each measurement is compared to the previous measurement, and the strain differences are added up to the absolute strain value. This method does not require a new experimental technique and will also work on old measurement files. It is also useful for other types of (OBR) strain measurements that contain many outliers and is not restricted to the investigation of cured epoxy.

Some large engineering structures are made by casting polymers into a mold. The structures can have complicated geometries and may be filled with other components, such as electrical transformers. This study investigated casting of large components made of epoxy. Epoxy is easy to pour, bonds well and has relatively low cure shrinkage. However, the cure shrinkage can lead to significant stresses or strains, causing large deformations that can lead to cracks.Understanding the curing process and related shrinkage is important for designing molds and controlling the production process. This study applied a new experimental method to measure strains due to cure shrinkage allowing many accurate local measurements along the length of an optical measurement fiber. The method is based on Optical Backscatter Reflectometry. Six distinct stages of the curing process can be identified. Previous measurements were limited to a few point measurements in small samples. This paper shows cure shrinkage in large samples and identifies some unexpected changes in behavior when going from small to large specimens. The behavior is explained qualitatively.

Bimodal hybrid in-situ nano-/micro-size TiC/Al composites were prepared with combustion synthesis of Al-Ti-C system and hot press consolidation. Attempt was made to obtain in-situ bimodal-size TiC particle reinforced dense Al matrix composites by using different carbon sources in the reaction process of hot pressing forming. Microstructure showed that the obtained composites exhibited reasonable bimodal-sized TiC distribution in the matrix and low porosity. With the increasing of the carbon nano tube (CNT) content from 0 to 100 wt. %, the average size of the TiC particles decreases and the compressive strength of the composite increase; while the fracture strain increases first and then decreases. The compressive properties of the bimodal-sized TiC/Al composites, especially the bimodal-sized composite synthesized by Al-Ti-C with 50 wt. % CNTs as carbon source, were improved compared with the composites reinforced with single sized TiC. The strengthening mechanism of the in-situ bimodal-sized particle reinforced aluminum matrix composites was revealed.

The in-situ TiB2/7050Al composite is a new kind of Al-based metal matrix composite (MMC) with super properties, such as low density, improved strength, and wear resistance. This paper, for a deep insight into its cutting performance, involves a study of the chip formation process and finite element simulation during orthogonal cutting in-situ TiB2/7050Al MMC. With chips, material properties, cutting forces, and tool geometry parameters, the Johnson–Cook (J–C) constitutive equation of in-situ TiB2/7050Al composite was established. Then, the cutting simulation model was established by applying the Abaqus–Explicit method, and the serrated chip, shear plane, strain rate, and temperature were analyzed. The experimental and simulation results showed that the obtained material’s constitutive equation was of high reliability, and the saw-tooth chips occurred commonly under either low or high cutting speed and small or large feed rate. From result analysis, it was found that the mechanisms of chip formation included plastic deformation, adiabatic shear, shearing slip, and crack extension. In addition, it was found that the existence of small, hard particles reduced the ductility of the MMC and resulted in segmental chips.