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Hydrothermal carbonization has been considered effective to reduce sewage sludge volume and provide an opportunity to generate valuable byproducts for a wide range of potential applications. The fate and distribution of nutrients during hydrothermal carbonization of sewage sludge, along with that of heavy metals, is very important for realizing nutrient recovery and reuse by both hydrochar and liquid phase directly as soil amendments and/or organic fertilizer. In this study, we systematically investigated the migration and transformation of nutrients and heavy metals using chemical extractions and reaction severity (Ruyter model) methods at a temperature range of 120–300 °C for 30–180 min. With increasing reaction severity, carbon and nitrogen efficiency of hydrochar showed a liner and exponential decrease respectively, while phosphorus accumulated positively in hydrochar. Nitrogen species in hydrochar are mostly nitrogen-containing aromatic heterocycles whereas in liquid phase are predominantly ammonia-N and organic-N. The organic phosphorus in sewage sludge was transformed to inorganic species but non-apatite phosphorus showed an exponential reduction in hydrochar with increasing reaction severity, together with the decrease of orthophosphate in liquid phase. As for heavy metals, hydrothermal carbonization promoted decrease in direct bioavailable fractions (except arsenic) and increase in stable fraction (except cadmium and arsenic) in hydrochar as reaction severity elevated. Since hydrothermal effects led to redistribution of nutrients speciation and immobilization of heavy metals, non-farm land application of both hydrochar and liquid phase seems to be possible and unrestricted. This study provides fundamental knowledges for the construction of sludge management strategies to better nutrients recycling and reclamation. Image 1 • Fate and distribution of nutrients with increasing reaction severity are identified. • Evolution of heavy metals speciation with increasing reaction severity is detected. • Hydrothermal effects promote the immobilization of heavy metals except for As. • Non-farm land application of orthophosphate rich hydrochar is possible. • Liquid phase is rich in NH 4 + N with implication to organic fertilizer production. [ABSTRACT FROM AUTHOR]

Kinetic regularities of catalytic liquid-phase oxidation of n-hexadecane in the presence of metal complexes of variable valence were studied. In the reaction of n-hexadecane oxidation as a catalytic mixture, a complex o-phenanthroline with stearate with variable valence metals (Mn2+, Cu2+, Co2+) was used. It found that o-phenanthroline significantly influences the catalytic activity of metal ions. The introduction of organic ligand into the catalytic system, as well as varying the ligand: metal salt ratio, has effect greatly on the course and character of the process. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Ongoing research has proven that Mg alloys can be introduced into the metal injection moulding process for the production of small parts in high quantities and of complex shape for medical as well as lightweight applications. Previously, development studies have been conducted using Mg and Mg-Ca alloys intended for medical application. However, progress towards the implementation of a process for technical and lightweight applications alloys with higher strength is needed. Therefore, in this study processing of conventional AZ81 alloy by MIM was successfully developed. Using this alloy, a yield strength of approximately 120 MPa and an ultimate tensile strength of approximately 255 MPa with elongation at fracture of approximately 7% was achieved. T4 heat treatment at 420 °C for 10 h does not reveal a positive influence on the mechanical properties this could be caused by an observed grain growth effect. This is in contrast to conventional material for example as cast, where T4 heat treatment is known to improve the mechanical properties especially elongation at fracture. [ABSTRACT FROM AUTHOR]

Abstract In the present work, the liquid phase amount during the sintering of lightweight bauxite was adjusted by adding fused magnesia micropowder. The addition of fused magnesia led to an increase in the liquid phase amount. The diffusion between the liquid phase and the solid phase increased and, consequently, favoured the migration of grains, which resulted in more pores becoming trapped between the grain boundaries. Therefore, the lightweight bauxite exhibited reduced open porosity, increased closed porosity and decreased pore size. However, when the amount of fused magnesia was further increased, the pinning effect and volume expansion caused by the formed spinel hindered the migration of the boundaries and led to a loose structure. Therefore, the closed porosity decreased and the open porosity increased instead. For our sintering conditions, with a liquid phase amount of around 17 wt%, lightweight bauxite with a low open porosity of 7.5%, a high closed porosity of 15.6% and a small median pore diameter of 5.03 µm can be fabricated. [ABSTRACT FROM AUTHOR]

Carbohydrate-binding modules (CBMs) have been developed to investigate the presence of crystalline and amorphous regions of cellulose. However, systematic and quantitative assessment of cellulose crystallinity using such non-hydrolytic fusion proteins in liquid phase has not been reported. In this work, cellulose directed CBM probes containing a green fluorescent protein (GFP) were constructed and named CG17, CG28, and CG2a. The probe binding condition was determined as incubating 30 μg/mL probes in 10 mM phosphate buffer at 30 oC for 60 min. Under the optimized condition, the linear correlations between CBM probe binding capability and X-ray diffraction (XRD) crystallinity were well established. Using linear regression equations, the crystallinity of several cellulosic materials was well calculated. Amorphous component and cellulosic surface area probably had a less effect on binding capability of CG2a than that of CG17 and CG28. Therefore, crystalline-region specific probe CG2a should be an efficient tool for interpreting the crystallinity of cellulosic materials. [ABSTRACT FROM AUTHOR]

Abstract Tungsten is a refractory metal, suitable for a broad range of high-temperature applications, due to its high melting point and high-temperature strength. Recently, tungsten alloys became of great interest in thermonuclear fusion research. The alloys maintain low sputtering yield and high melting point, but greatly improve some drawback properties comparing to pure tungsten. These alloys are commonly prepared by mechanical alloying and compacted using Spark Plasma Sintering/Field Assisted Sintering. Powder in a graphite die is consolidated by applying pulsed electric current and pressure. Graphite foil is commonly placed between the die and the powder, to prevent adhesion. However, for number of applications it is necessary to avoid carbon contamination. In the present study we have examined carbon contamination mechanism of W - 10 wt.%Cr - 1 wt.%Hf alloy during Field Assisted Sintering along with the alloy's properties. The experiments have shown that the graphite foil leads to significant dealloying via mechanism of liquid phase sintering. As a result, tailored properties of the material are deteriorated after several minutes of the consolidation process. Therefore, application of carbon diffusion barrier was proposed, examined and compared with the alloy sintered with graphite foil. Highlights • W-Cr alloys have been sintered at the temperature above miscibility gap • Standard sintering procedure leads to dealloying, degradation of the tailored properties and contamination by carbon • Liquid sintering is the mechanism responsible for in-depth Cr depletion and carbon contamination • Tungsten foil eliminates formation of the liquid and thus preserve the solid solution and minimise the carbon contamination • This study provides a guide to W-Cr alloys sintering with respect to the temperature [ABSTRACT FROM AUTHOR]

Liquid-phase hydrogenation of 4-chloronitrobenzene (4-CNB) to 4-chloroaniline (4-CAN) under mild reaction conditions (0.6 MPa, 25 °C, methanol-diethyl ether, 1:1 vol.) over palladium and platinum catalysts containing 1 mass% of metal supported on beta zeolite (M/B) or γ-alumina (M/A) was studied. The catalysts were prepared by the incipient wetness method using amino nitrate complexes and hydrogen as the reducing agent. SEM, adsorption-desorption nitrogen isotherms, XRD, TEM, and hydrogen chemisorption techniques were used for their characterization. The techniques employed revealed the presence of relatively large metal particles (approximately 15 nm; about 3% of metal dispersion). Stability of the catalysts during the hydrogenation was high; no catalyst changes were observed after two recycle runs. Hydrogenation over M/A catalysts was found to be faster than that over M/B catalysts in the methanol-diethyl ether mixture. Selectivity of only about 75% to 4-CAN was achieved over the M/A catalyst in methanol. Positive effect of the acid support (beta zeolite) and low polarity of the reaction environment (diethyl ether) are reflected in the high selectivity to 4-CAN; of about 99% at virtually 100% conversion of 4-CNB. [ABSTRACT FROM AUTHOR]

In this study, liquid-phase aerobic oxidation of toluene catalyzed by Mn-Mo oxide was conducted in a 1.0 L batch reactor. The macroscopic kinetics of toluene consumption and benzaldehyde generation at 413-443 K were obtained from a combination of experimental observation and hypothetical models. The results clearly showed that both the oxidation rate of toluene and generation rate of the aromatic product were proportional to the concentration of the substrate, the partial pressure of oxygen and the surface area of the catalyst. The energy barrier of toluene oxidation to benzyl alcohol was the highest (≈ 81 kJ mol−1), while that of benzyl alcohol oxidation to benzaldehyde was the lowest (≈ 57 kJ mol−1). Moreover, the activation energy of further oxidation of benzaldehyde in an acetic acid solvent was only slightly lower (≈ 1.9 kJ mol−1) than that of toluene oxidation. Significantly, the transformation of benzyl alcohol indeed contributed to the generation of benzaldehyde and this step conformed to a first-order parallel-consecutive model. Increased reaction temperature and residence time favored the transformation of benzyl alcohol to benzaldehyde. In addition, doping with molybdenum at Mn/Mo = 3/1 enhanced the catalytic performance of the heterogeneous catalyst and was attributed to the presence of a synergetic effect between different metal cations. Regarding the microscopic kinetics, the LH-OS-ND mechanism (Langmuir-Hinshelwood adsorption of reagents on the same type of active sites and non-dissociative adsorption of oxygen) was verified as responsible for the heterogeneous oxidation of toluene. Oxygen and benzaldehyde were weakly adsorbed (ΔHads,Oxy ≈ − 15 kJ mol−1, ΔHads,Bald ≈ − 30 kJ mol−1), but showed strong mobility (ΔSads,Oxy ≈ − 22 J mol−1 K−1), ΔSads,Bald ≈ − 39 J mol−1 K−1). The fundamental intrinsic rates were deduced based on the LH-OS-ND mechanism and showed great consistency with the macroscopic results. [ABSTRACT FROM AUTHOR]

Highlights • At-line, off-line , in-line / on-line , in-situ applications of process analytical tools (PAT) are presented. • The combination of tools, incl. data analysis and correlation methods is described. • The importance of in-situ, multi-parameter, and -position techniques is discussed. • A tool for mobile multi-parameter measurements in the large-scale is presented. Abstract Recent advances in sensor development and miniaturization offer new possibilities to monitor and control bioprocesses. Specific requirements for anaerobic processes in terms of low costs and high robustness against insoluble fractions and impurities in media led to a decelerated penetration of new technology in this field. Since no regulatory framework demands for process monitoring and documentation like in the pharmaceutical industry, the implementation of new sensors beyond long-established methods is not conducted as intensively. Nevertheless, many attempts have been made in recent years to adopt sensors and show their applicability in anaerobic fermentation processes. New possibilities arise for improved monitoring, control and faster process development through digitalization. This review aims to provide an overview over these recent attempts with the focus on the liquid phase in the upstream part of pure culture bioprocesses for anaerobic bulk compound, food, and beverage production. In particular, methods that monitor the viability, metabolic activity or related parameters are discussed, like electrochemical, impedance and spectroscopy probes, and methods related to fluid flow and gradient formation, like acoustic and mobile sensors. [ABSTRACT FROM AUTHOR]

The laws of changing the presolidification supercooling of bismuth drops during continuous thermal cycling were studied by thermal analysis in the temperature–time coordinates. A sawtooth cyclic dependence of the supercooling on the sequence of heating and cooling cycles, which is described by a Fourier function, is detected. An expression is derived for the energy of coagulation of nuclei, and it is used to find a relation between the experimental and calculated supercoolings. The obtained results are interpreted in terms of a cluster-coagulation solidification model and the anomalous properties of bismuth in melting and solidification. [ABSTRACT FROM AUTHOR]

The stability of particle suspensions, which is important in numerous industrial processes, is generally dominated by the interaction forces between the suspended particles. Understanding the interaction forces between surfaces in liquids is therefore fundamentally important in order to evaluate and control how particulates, including fluid droplets in emulsions and air bubbles in foams, behave in various systems. The invention of the surface force apparatus (SFA) enabled the direct measurement of interaction forces in liquids with molecular level resolution and it has led to remarkable progress in understanding surface forces in detail. Following the SFA, the application of atomic force microscopy (AFM) to force measurement has further extended the possibility of force measurements to a broad field of research, mainly due to the range of materials that can be employed. This review provides an overview of developments in the investigation of interaction forces between surfaces using AFM. The properties of various interaction forces, important in particle technology, revealed by the studies using AFM are described in detail. [ABSTRACT FROM AUTHOR]

Thin film piezoelectric-on-silicon (TPoS) elliptical resonators are presented in this paper. The micro-resonators are composed of two rectangular resonant plates vibrating out-of-phase at the first length-extensional mode, which are coupled through arches on sides. In this way, extensional motions of rectangles are converted to rotational motions via arches which make the resonator suitable for operation under water, where all sidewalls of the resonator vibrate in parallel with liquid to maintain high liquid phase quality factors (${Q}$). Thanks to wide electrode area available on rectangular plates, strong piezoelectric transduction is achieved leading to low liquid phase motional resistances. Different variations of the resonators were designed and fabricated to operate at different resonance frequencies. The TPoS elliptical resonators exhibit high ${Q}\text{s}$ up to 7400 for operation in air while showing liquid phase ${Q}\text{s}$ as high as 200. An elliptical resonator operating at 4 MHz with the lowest motional resistance of 5.6 $\text{k}\Omega $ was involved in an oscillation circuit with a single-stage sustaining amplifier exhibiting frequency stability of $2\times 10^{-7}$ ($\Delta f/f_{0}$). Such high stability makes such resonators an excellent choice for high-resolution mass or viscosity sensing at liquid phase such as biosensing applications. [ABSTRACT FROM AUTHOR]

Isobaric heat capacities of ten selected aliphatic octanols (3-octanol, CAS RN: 589-98-0; 2,2,4-trimethyl-3-pentanol, CAS RN: 5162-48-1; 2,2-dimethyl-3-hexanol, CAS RN: 4209-90-9; 2,3-dimethyl-3-hexanol, CAS RN: 4166-46-5; 2,4-dimethyl-3-hexanol, CAS RN: 13432-25-2; 2,5-dimethyl-3-hexanol, CAS RN: 19550-07-3; 3,5-dimethyl-3-hexanol, CAS RN: 4209-91-0; 4-ethyl-3-hexanol, CAS RN: 19780-44-0; 3-methyl-4-heptanol, CAS RN: 1838-73-9; 4-methyl-4-heptanol, CAS RN: 598-01-6) were measured with a Tian-Calvet calorimeter in the temperature range from 257 to 358 K; this temperature range was extended up to 423 K with a heat-flux DSC. For all studied compounds, a maximum on temperature dependence of heat capacity was observed; this feature was corroborated by FTIR spectroscopy performed from 303 K to a maximum of 463 K. Such maxima are related to disintegration of oligomers kept together by hydrogen bonds. The role of steric hindrance on hydrogen bonding is discussed. It is apparent that temperature of maxima is very sensitive to steric hindrance; however, further effort is required for full understanding of hydrogen bonding in aliphatic octanols. [ABSTRACT FROM AUTHOR]

A model is discussed describing the interaction of liquid droplets with interblade channel walls in condensing steam turbines. It is based on the experimental data on the impact of individual droplets on a surface that are presented in the form of statistical models with free empirical parameters. The motion of liquid particles is simulated using individual streams of droplets under the action of aerodynamic drag force from the steam. Their interaction with the interblade channel surface is determined by the kinetic energy of impingement affecting the subsequent process. The proposed numerical approach deals with two droplet impact cases, i.e., a droplet deposits on the profile of the blade airfoil or becomes a source of secondary moisture leaving the surface. Liquid droplets formed in the latter case are also simulated using streams. The empirical coefficients of the model were selected based on the results of experimental investigation of the motion of liquid particles in a flat vane cascade. Parameters of wet steam flow in an interblade channel were determined using a laser flow diagnostic system and the particle tracking velocimetry (PTV) method implemented on its basis. The investigations were performed in a two-dimensional flow. The measured patterns of liquid particles’ motion were compared with predicted ones. The velocity distributions of primary and secondary droplets were examined in six characteristic regions of the flat cascade. Causes responsible for disagreement between the experiment and the predictions were outlined. It has been found that the angle at which droplets impinge on the interblade channel wall has a considerable effect on characteristics of the formed secondary droplets. Verification of the model demonstrated a satisfactory agreement of the experiment with the predictions. [ABSTRACT FROM AUTHOR]

Fast development of centralized agricultural biogas plants leads to high amounts of digestate production. The treatment and disposal of liquid fractions after on-site digestate solid–liquid separation remains problematic due to their high organic, nutrient and aromatic contents. This work aims to study the variability of the remaining compounds in the digestate liquid fractions in relation to substrate origin, process parameters and solid–liquid separation techniques. Twenty-nine digestates from full-scale codigestion biogas plants and one waste activated sludge (WAS) digestate were collected and characterized. This study highlighted the combined effect of the solid–liquid separation process and the anaerobic digestion feedstock on the characteristics of liquid fractions of digestates. Two major clusters were found: (1) liquid fractions from high efficiency separation process equipment (e.g., centrifuge and others with addition of coagulant, flocculent or polymer) and (2) liquid fractions from low efficiency separation processes (e.g., screw press, vibrating screen and rotary drum), in this latter case, the concentration of chemical oxygen demand (COD) was associated with the proportion of cow manure and energy crops at biogas plant input. Finally, SUVA254, an indicator for aromatic molecule content and the stabilization of organic matter, was associated with the hydraulic retention time (HRT).

The argyrodite solid electrolyte Li 6 PS 5 Cl is one of the promising candidates due to its high Li-ion conductivity for the application of all-solid-state lithium-ion batteries (ASSLIBs). Unfortunately, Li 6 PS 5 Cl argyrodite exhibits low stability against lithium metal anodes and oxide cathodes. One way to improve stability is by oxygen doping into Li 6 PS 5 Cl argyrodite. In this work, Li 6 PS 5 – 2.5x O 2.5x Cl (x = 0, 0.05, and 0.10) solid electrolytes with oxygen doping were successfully synthesized using liquid-phase synthesis for the first time. Therefore, the solid electrolyte with x = 0.05 exhibits high ionic conductivity with enhanced electrochemical stability against lithium metal and oxide cathodes. Argyrodites with x = 0.05 and x = 0.10 show superior capacity retention and higher Coulomb efficiency compared to x = 0. Moreover, the solid electrolytes also demonstrate better stability during Li symmetrical cell measurements. This experiment provides a controllable amount of oxygen doping into the Li 6 PS 5 Cl argyrodite solid electrolyte system in order to achieve high performance of ASSLIBs through liquid-phase synthesis. • The incorporation of P 2 O 5 oxide into sulfide-based Li 6 PS 5 Cl argyrodite solid electrolyte has been explored. • Oxide doping in argyrodite is achieved for the first time through liquid-phase synthesis. • We used Acetonitrile (ACN) and 1-Propanethiol (PTH) in our liquid-phase synthesis for the first time. • Doping oxides into argyrodite enhances battery cycle performance and lithium metal stability. [ABSTRACT FROM AUTHOR]

In this paper the influence of barium strontium titanate (BST) xerogel as a sinter additive and BaCu(B₂O₅)(BCB) as a liquid phase sintering aid on the sintering behavior of BST bulk ceramics is investigated. BST as well as BCB powders were synthesized via a mixed oxide route and BST gel via a sol-gel process. Compared to pure BST bulk ceramics, BST gel reduces the sintering start (onset temperature) by up to 174°C and increases the density for a sintering temperature of 1200°C. By adding BCB to the BST powder the sintering was completed much faster and the onset temperatures were reduced by 281°C and 312°C for 1 mol% and 2.5 mol%, respectively. With 2.5 mol% BCB, the highest density of 96 % (5.41 g/cm³) was achieved at 950°C.

Rumen microbiota plays an important role in animal productivity, methane production and health. Several different locations have been used to obtain rumen samples (i.e., liquid-phase samples, solid-phase samples, buccal swabs) in previous studies. Here we assess differences in the rumen microbiota between solid- and liquid-phases of the rumen under differing dietary conditions (white clover vs. perennial ryegrass); there were 4 sample types: liquid-associated/grass (LG), solid-associated/grass (SG), liquid-associated/clover (LC), and solid-associated/clover (SC). Four Holstein-Friesian cows were strip grazed on pure stands of perennial ryegrass or white clover in a change-over design experiment with 3 periods (each lasting for 3 weeks). Solid- and liquid- phase microbes were obtained following total rumen evacuation on the penultimate day of each period. DNA was extracted and multiplexed libraries sequenced using 16S next generation sequencing (Illumina MiSeq). Demultiplexed sequences underwent quality control and taxonomic profiles were generated for each sample. Statistical analysis for the effects of diet and phase was conducted both overall [using non-metric multidimensional scaling (NMDS) and diversity indices] and for individual taxa. Separation of both diet and phase was observed NMDS, with significant effects of diet (P < 0.001) and phase (P < 0.001) being observed. Regardless of diet, Prevotella was most abundant in the liquid samples. When assessing differences between phases, the majority of statistically significant taxa (predominantly from Archaea and the order Clostridiales) were found at higher relative abundances in solid-phase samples. Diversity (Shannon Index) was lower in the liquid-phase samples, possibly because of the higher relative abundance of Prevotella. A presence vs. absence approach, followed by Chi-squared testing, was adopted. Differences between phases (LG vs. LC, LC vs. LG, SG vs. SC, and SC vs. SG) and differences between phases for the clover diet (LC vs. SC and SC vs. LC) were significant (P < 0.001); differences between phases for the grass diet were non-significant. Sampling technique has a profound impact on reported microbial communities, which must be taken into consideration, particularly as archaea may be underestimated in the liquid-phase.

Microwave sintering process was employed to agglomerate ferromanganese alloy powders. The effects of sintering temperature, holding time and particle size composition on the properties and microstructure of sintering products were investigated. The results was shown that increasing sintering temperature or holding time appropriately is beneficial to increase the compressive strength and volume density. SEM and EDAX analysis shows that the liquid phase formed below the melting point in the sintering process, which leads to densification. XRD patterns indicate that the main reaction during microwave sintering is the decarbonization and carburization of iron carbide phase. The experiment demonstrate that the optimum microwave sintering process condition is 1150°C, 10 min and 50% content of the powders with the size of –75 μm