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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. [ABSTRACT FROM AUTHOR]

In-situ biomethanation combines conventional biogas production from the anaerobic digestion (AD) of organic matter with the addition of hydrogen to produce a higher quality biomethane gas. However, challenges surrounding its performance and control could hinder its uptake. To investigate this, an automated rig was designed and operated to study in-situ biomethanation with sewage sludge (SS) and food waste (FW) feedstocks. The effects that were experimentally investigated included the biogas recirculation rate, stirring intensity, and organic loading rate (OLR). All the results highlighted the rate-limiting effect of H2 gas–liquid mass transfer (measured kLa in the range of 43–82 day−1), which was implied by a lack of evidence of hydrogen-induced biological inhibition and a high average equilibrium hydrogen content in the biogas (a volume of 7–37%). At an OLR of 2 g VS L−1day−1, increasing biogas recirculation and mechanical stirring rates improved the methane evolution rate up to 0.17 and 0.23 L L−1day−1 and the H2 conversion up to 80 and 66% for sewage sludge and food waste, respectively. A lower OLR of 1 g VS L−1day−1 allowed for increased hydrogen conversion but at a lower level of methane productivity. A process model, validated on experimental data, predicted that improving the kLa to at least 240 day−1 would be required for in-situ biomethanation at OLRs common in AD systems in order to achieve a drop-in quality in terms of the biogas, with further downstream treatment required for certain applications. [ABSTRACT FROM AUTHOR]

Accurately measuring the critical shear stress is crucial for numerous applications, such as sediment transport modeling, erosion prediction, and the design of sustainable coastal engineering structures. However, developing reliable and precise in-situ measurement devices faces significant challenges due to the harsh and dynamic nature of aquatic environments. Factors like turbulence and waves introduce complexities that must be considered when designing and calibrating these devices. The newly developed Openable Underwater Carousel In-situ Flume (OUC-IF) was used to determine the critical shear stress (τc) and quantify erosion rates. Acoustic Doppler Velocimeter (ADV) was employed to measure 3D near-bottom velocities, which were then used to estimate and pre-calibrate bed shear stress (τ) applied on the seabed in the annular flume. Three computation methods of shear stress were evaluated: turbulent kinetic energy (TKE), direct covariance (COV), and log profile (LP). In-situ erosion experiments were conducted for the first time at two sites in the tidal flat of the Yellow River Delta (site 1 with a water depth of 1.32 m and site 2 with a water depth of 0.75 m). The critical shear stress was found to be 0.10 Pa at site 1 and 0.19 Pa at site 2, and the erosion rates of the sediments were successfully measured. The effect of wave-seabed interactions on erosion resistance was explored by theoretically estimating the wave-induced pore pressure of the seabed based on the observed data. The max liquefaction degree of the seabed at site 1 and site 2 was 0.035 and 0.057, respectively, and the average erosion coefficient Me was 2.63E-05 kg m-2s-1 at site 1 and 3.48E-05 kg m-2s-1 at site 2.

Crack spacing and crack opening displacement values are critical for CMC damage and oxidation modeling. A tensile stage used with light and scanning electron microscopy (SEM) was utilized to evaluate micro-cracking under load in SiC/BN/SiC ceramic matrix composites (CMCs). Surface micro-crack spacing and crack composition, a novel measurement introduced in this work, were measured with light microscopy at room temperature. Crack spacing decreased with increasing load, with a majority of cracks being in contact with BN fiber coatings. Crack opening displacement (COD) measurements were taken at room and elevated temperature (600 °C) with scanning electron microscopy. CODS increased nearly linearly with increased load; CODs ranged from 1 to 3 μm at 200–350 MPa at room temperature and at 600 °C ranged from 0.5 to 2 μm at 175–350 MPa. CODs were also related to local microstructure, with CODS being lower near longitudinal fiber tows. Implications on use of the data for CMC oxidation models are discussed.

The unique in situ measurements of clouds and precipitation within the shallow and deep cumulus over the north-eastern Arabian Sea region during the Indian monsoon are illustrated in this study with a focus on droplet spectral parameters. The observational period showed a significant incursion of Arabian dust and the presence of giant cloud condensation nuclei (GCCN), modifying the cloud and precipitation spectral properties. Warm rain microphysics supported the mixed-phase development in these clouds and exhibited hydrometeors of snow, graupel and large aggregates as part of ice processes. Cloud base droplet number concentration is about 142 $\pm $ 79 cm ^−3 which is one third of the cloud condensation nuclei (CCN) number concentration at 0.2% supersaturation. A rapid broadening of droplet size distribution (DSD) near to the cloud base was noted in contrast to polluted continental clouds. Relationship between the relative dispersion ( $\varepsilon ;$ the ratio of DSD spectral width ( $\sigma $ ) to mean radius ( ${r}_{m}$ )) and liquid water adiabatic fraction (AF) indicates that the entrainment effect has increased relative dispersion significantly (2–3 times larger) in these clouds. Effective radius ( ${r}_{{eff}}$ ) is found to be proportional to mean volume radius ( ${r}_{v}$ ) with a proportionality constant ( $\beta $ ) that varies between 1.0–1.6, depending on the spectral dispersion parameter. Drop size distributions for the small cloud droplets with size range 2–50 $\mu $ m and the large drizzle drops (or ice hydrometeors) with size range 100–6400 $\mu $ m are parameterized using the gamma function distributions useful for large-scale cloud models.

The present research aims to study the dry turning machinability characteristics of in situ Al-4Mg/MgAl _2 O _4 nanocomposite by High-Speed Steel tool. The influence of various machining process parameters, such as feed rate, depth of cut and cutting speed on the surface roughness and cutting force of the nanocomposites was measured while performing dry turning. From the turning operation results, it is noticed that up to 100 m min ^−1 , the cutting force increased and with further increases in cutting speed, the cutting force starts decreasing up to 150 m min ^−1 . The type of chips and built-up edge (BUE) development were studied using a scanning electron microscope. BUE formations were higher at low cutting speeds (50 m min ^−1 ) and lower at high cutting speeds (150 m min ^−1 ). At a given depth of cut and feed rate, with an increase in cutting speed, the length of the chip and chip curls increased. Further, higher 2 wt% of in situ MgAl _2 O _4 addition changes long-curled chips to segmental-type chips. With a feed rate of 0.14 mm/rev, the Al-4Mg/1 wt% MgAl _2 O _4 nanocomposite showed the lowest surface roughness value of 2.4 μ m proving usage of high speed steel can provide a better surface finish while turning Al-4Mg/MgAl _2 O _4 nanocomposite.

This work gives an overview on different technological solutions for polysilicon removal in industrial tunnel oxide passivated contact (i-TOPCon) n-type silicon solar cell fabrication. The removal of parasitically deposited poly-Si layers on the front and the edges is a mandatory requirement for a low reverse bias junction leakage current (Irev). A polysilicon removal study on wafer level shows (i) that the efficient removal of the surface oxide layer before poly-Si etching is crucial to achieve short etching times and (ii) that an additive in the KOH solution enhances etching selectivity between poly-Si and silicon oxide surfaces. To evaluate the impact on device level, TOPCon cells have been fabricated in parallel using in-situ n-doped PECVD and LPCVD layers, as well as ex-situ LPCVD poly-Si layers, with another variation of poly-Si removal processes, namely wet chemical inline, wet chemical batch cluster and atmospheric dry etching (ADE). Our results show that a two-minute inline polysilicon removal in hot KOH meets the Irev qualification in case of as deposited in-situ doped layers, whereas for ex-situ doped layers a batch process with a five-minute KOH etching time is needed. LPCVD poly-Si cells show efficiencies above 23%, PECVD poly-Si cells with a batch cluster poly-Si removal process up to 23.4%.

In-situ polymerization is a method for fabricating lithium-ion batteries to contain solid or gel electrolytes without major manufacturing changes. Gel polymer electrolytes (GPEs) wherein some polymer in incorporated, decreasing the volume of liquid electrolyte, have been pursued as they may be safer. One challenge with GPEs is reduced ion transport properties. In this work, macromonomers with different chain chemistry and ionic monomers are crosslinked on electrospun polyvinylidene difluoride (PVDF) in the presence of solvents, without conventional salt, to in-situ fabricate GPEs with elevated transference number within coin cells. These GPEs would be single-ion conductors in the case of complete ionic monomer polymerization to the crosslinked network. The effect of chain chemistry and the percentage of macromonomers and ionic monomers in the GPEs on conductivity are investigated. It is found that poly(siloxane) diacrylate (PDMSDA)- and perfluoropolyether tetra-acrylate (PFPETA)-based GPEs outperform the poly(propylene glycol) diacrylate (PPGDA)- and poly(tetrahydrofuran) diacrylate (PTHFDA)-based GPEs in terms of ionic conductivity. The highest ionic conductivity was achieved for a PDMSDA-based GPE at 4.2 × 10 ^−4 S cm ^−1 at 23 °C. Graphite/NMC-811 full cells prepared with the in-situ polymerized PDMSDA-based GPEs show capacity retention of 82.6% after 100 cycles, albeit with limited electrode utilization due to ion transport limitations.

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.

Four Ti53−xZr20Nb10Cu5Be12Agx (x = 0, 1, 3 and 5 at.%) bulk metallic glass composites (BMGCs) with various size, volume fraction and morphology of in-situ crystal phase were prepared by the arc-melting method. The shear bands extensions under strain of 5% and 20% were observed to explore the contributions of in-situ crystal phase on the deformation behaviors. The results showed that addition of Ag element significantly increased the glass forming ability. When Ag addition increased from 0 to 5 at.%, the volume fraction of in-situ crystal phase decreased from 74.5% to 38.3%, the morphology transformed from the dense cluster to the spotted shape, resulting in the decrease of dendrites span length (L) and the increase of dendritic arm spacing (DAS). The size, volume fraction and morphology of in-situ crystal phase had great influence on the initiation and extensions of shear bands. In the in-situ BMGCs, the crystal phases with the appropriate size, volume fraction and morphology were conducive to the initiation of multiple shear bands and could effectively restrain the expansion of single shear band, improving the plasticity, and the in-situ BMGCs with Ag element of 3 at.% exhibited the highest plasticity of 17.9%.

Tungsten carbide (WC) particle reinforced Ni3Al intermetallic matrix composites (WC–Ni3Al) was first fabricated by in situ thermite reaction. The microstructure and high temperature wear resistance of the WC-Ni3Al composite have been studied. The WC-Ni3Al composite contains Ni3Al, WC and B2 phases, and the volume fraction of Ni3Al, WC and B2 were 55.27%, 10.67% and 34.06%, respectively. The WC-Ni3Al composite exhibits excellent friction and wear resistance. Our findings have important engineering implications for the preparation of intermetallic matrix composites.

Hydroxyapatite (HAp) is a vital material in various biomaterials but has low flexibility. Because of that, research has been done to increase the efficiency of hydroxyapatite by combining it with polyethylene glycol (PEG). HAp-PEG composite synthesis using blood cockle shell waste (Anadara granosa) as Ca precursor. The HAp-PEG composite was synthesized by in-situ to avoid high agglomeration. It was carried out with various temperatures to study the effect of temperature on the formation of the HAp-PEG composite and to determine the effect of temperature on its morphology and degradation properties. Fourier-Transform infrared (FTIR) characterization showed the presence of HAp and PEG functional group vibrations. X-Ray Diffraction (XRD) analysis showed that the composite had HAp peaks that matched the standard HAp ICSD #97849 and corresponded to pure PEG peaks. Characterization of Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) It is known that the synthesis temperature affects the morphology and hydroxyapatite ratio. Thermogravimetric Analysis-Differential Thermal Analysis (TGA-DTA) analyzed weight reduction in HAp-PEG composite samples, showing that the composite experienced a significant decrease in mass at 176–306, indicating PEG decomposition. The HAp-PEG composite degradation behavior test confirmed that the optimum temperature for degradation occurred at 70 ​°C.