Solid Precipitation Research Articles

How changes in the circulation patterns specific to the solid precipitations can affect these meteorological events in the Alpine stations of the Mediterranean region? Use of the ERA5 reanalyses

How changes in the circulation patterns specific to the solid precipitations can affect these meteorological events in the Alpine stations of the Mediterranean region? Use of the ERA5 reanalyses

Pollutants Migration and Solid Precipitate Characteristics During the Treatment of Concentrated Leachate from Waste Incineration Plant Based on Direct Contact Evaporation Method

Pollutants Migration and Solid Precipitate Characteristics During the Treatment of Concentrated Leachate from Waste Incineration Plant Based on Direct Contact Evaporation Method

A new reference-quality precipitation gauge wind shield

Abstract. Gauge-based precipitation measurements suffer from undercatch due to the effects of wind, with solid-precipitation measurements especially susceptible to such errors. When it is snowing and windy, unshielded precipitation gauges can catch less than half of the amount of precipitation of a gauge that is protected from the wind. For this reason, the US Climate Reference Network (USCRN) developed a large, double-layer, wooden wind shield called the Small Double Fence Intercomparison Reference (SDFIR). In past studies, the SDFIR has been demonstrated to be the most effective wind shield in use in any weather or climate network, reducing solid-precipitation undercatch to less than 10 % in wind speeds up to 8 m s−1. However, the wooden SDFIRs are subject to decay, they are difficult to replace and maintain, and they hinder access to maintaining the gauge. For these reasons, a new precipitation gauge wind shield called the Low Porosity Double Fence (LPDF) has been developed for use in the USCRN. Tested at three separate sites chosen for prevalent windy and snowy weather, the precipitation measurements recorded within the LPDF compared well to the SDFIR. After more than 2 years of measurements, the total precipitation recorded by the LPDF at each individual site differed by ±1.2 %, and the total LPDF accumulation from all sites was 0.03 % greater than the SDFIR accumulation. For the measurement of solid precipitation, the LPDF-shielded measurements were statistically indistinguishable from those in the SDFIR shield, and the time series of accumulation from precipitation gauges shielded by the SDFIR and the LPDF were almost identical. This new wind shield is much smaller and easier to install and maintain than any other reference-quality wind shield for the measurement of solid precipitation and may be of use within other meteorological, hydrological, and climate networks. It could also serve as a secondary reference precipitation measurement for precipitation intercomparisons held in remote locations where the construction of a full-sized Double Fence Intercomparison Reference (DFIR) shield is not feasible.

Recovery of 400 Chemicals with Three Extraction Methods for Low Volumes of Human Plasma Quantified by Instrumental Analysis and In Vitro Bioassays.

Human biomonitoring studies are important for understanding adverse health outcomes caused by exposure to chemicals. Complex mixtures of chemicals detected in blood - the blood exposome - may serve as proxies for systemic exposure. Ideally, several analytical methods are combined with in vitro bioassays to capture chemical mixtures as diverse as possible. How many and which (bio)analyses can be performed is limited by the sample volume and compatibility of extraction and (bio)analytical methods. We compared the extraction efficacy of three extraction methods using pooled human plasma spiked with >400 organic chemicals. Passive equilibrium sampling (PES) with polydimethylsiloxane (PDMS) followed by solid phase extraction (PES + SPE), SPE alone (SPE), and solvent precipitation (SolvPrec) were compared for chemical recovery in LC-HRMS and GC-HRMS as well as effect recovery in four mammalian cell lines (AhR-CALUX, SH-SY5Y, AREc32, PPARγ-BLA). The mean chemical recoveries were 38% for PES + SPE, 27% for SPE, and 61% for SolvPrec. PES + SPE enhanced the mean chemical recovery compared to SPE, especially for neutral hydrophobic chemicals. PES + SPE and SolvPrec had effect recoveries of 100-200% in all four cell lines, outperforming SPE, which had 30-100% effect recovery. Although SolvPrec has the best chemical recoveries, it does not remove matrix like inorganics or lipids, which might pose problems for some (bio)analytical methods. PES + SPE is the most promising method for sample preparation in human biomonitoring as it combines good recoveries with cleanup, enrichment, and potential for high throughput.

Effects of silicon and neodymium additions on microstructures and mechanical properties of CoCrNi medium entropy alloy films

A series of (CoCrNi)100–x–ySixNdy medium entropy alloy films (MEAFs) with manipulated metalloid element, Si, and rare earth element, Nd, was synthesized using magnetron three-target co-sputtering. A transition from single FCC phase to the coexistence of FCC CoCrNi, HCP CoCrNi and HCP NdNi5 phases was observed in XRD and TEM diffraction patterns with the increasing Nd content for Si content of ∼0.7 at.%, and the SEM and TEM images showed the refined columnar grains. The hardness and compressive yield strength reached the maxima of 10.29 and 4.27 GPa, respectively, in Si0.61Nd5.14 film due to the solid solution strengthening, grain refinement and precipitation strengthening. However, The films exhibited a transition from fully crystalline to crystalline within the amorphous matrix in XRD and TEM results with the increasing Si content for Nd content of ∼2.6 at.%, and the columnar structure disappeared in the SEM and TEM images. The hardness and yield strength increased slightly to the maxima of 9.75 and 4.10 GPa, respectively, in Si0.76Nd2.91 film attributed mainly to the interstitial solid solution strengthening. Discussion on (CoCrNi)100–x–ySixNdy MEAFs showed the optimized mechanical properties in Si0.61Nd5.14 film, indicating that precipitation strengthening and grain refinement could be the major strengthening mechanisms in this system.

Sedimentation-Based Separation and Purification of Solid Industrial Waste: A Case Study of Phosphogpusym.

The continuous accumulation of solid industry waste, such as phosphogypsum, has emerged as a global environmental hazard and a significant obstacle to achieving a green and sustainable industry. To convert this industry waste to reusable resources, the development and implementation of simple and cost-efficient purification techniques is crucial. A sedimentation-based separation approach was developed to achieve this objective. Through a sedimentation process, a suspension of phosphogypsum particles is transformed into three distinct phases: a supernatant liquid, a concentrated slurry, and a solid precipitate. These phases primarily consist of soluble salts, a mixture of oxides and organic matter, and calcium phosphate dihydrates mixed with calcium phosphate, respectively. Through a sedimentation process, calcium sulfate dihydrate concentration can be significantly enhanced from 87.45 to 91.60% and further improved to 95.72% by repeating the sedimentation process three times. The various components obtained from this process can be effectively reused as mineral resources, soil amendment, and industry gypsum. The sedimentation process is expounded upon using both the classical mechanics model and Stokes' law. To foster a seamless industrial application, we have also designed a continuous settling skittle and a trail setup for industrial treatment of phosphogpysum. This innovative technique holds immense promise for its broader application, especially within but not limited to the phosphoric acid industry.

Ultrahigh strength and ductility combination in Al40Cr15Fe15Co15Ni15 triple-phase high entropy alloy

In this work, we developed the as-cast triple-phase Al40Cr15Fe15Co15Ni15 HEA composing of B2, BCC and σ phases. The triple-phase Al40Cr15Fe15Co15Ni15 HEA shows an excellent strength-plastic combination, with yield strength of 1454 MPa, compressive strength of 3628 MPa, ductility of 38 % and specific yield strength of 266.4 MPa cm3/g. These mechanical properties of the Al40Cr15Fe15Co15Ni15 HEA were attributed to the combined effects of solid solution strengthening, precipitation strengthening and grain boundary strengthening caused by high Al atom concentration. The outstanding mechanical performance makes the triple-phase Al40Cr15Fe15Co15Ni15 HEA an aussichtsreich engineering material.

Process monitoring of cobalt carbonate precipitation by reactions between cobalt sulfate and sodium carbonate solutions to control product morphology and purity

Recovering critical elements from EV batteries is challenging as the separation is a complex process which involves different processing parameters. Cobalt (Co) is one of the metals which ensures the life of EV batteries and here we have successfully precipitated cobalt carbonate (CoCO3) by semi-batch precipitation using cobalt sulfate and sodium carbonate as reactant solutions. The precipitation of cobalt carbonate was investigated by offline Raman spectroscopy, Powder X-ray diffraction analysis, inline Focused Beam Reflectance Measurement (FBRM), and pH measurements. In addition, the effects of various factors including pH, aging time, reactant addition time, mixing speed, and temperature on cobalt carbonate precipitation and the properties of the precipitated solids were investigated. In the process of precipitation, the carbonate ions in the initial electrolyte solution were converted to bicarbonate ions during the addition of acidic cobalt sulfate solution, which consequently decreased the pH in the suspension. When the pH was lower than 8, the carbon mainly existed as bicarbonate and the cobalt carbonate started to precipitate at a high efficiency. Cobalt initially precipitated as cobalt carbonate hydroxide (Co2CO3(OH)2) at a higher pH (9–11) and converted to cobalt carbonate at a lower pH (6.5–8). The crystallite size of cobalt carbonate calculated for the different reaction conditions shows that the growth response is high at longer reactant addition time and high temperature. The morphology of the final cobalt carbonate precipitate was small single spherical crystals and their aggregates. The purity of precipitates could be increased by reducing the aggregation tendency during the precipitation.

Spatial pattern of glacier mass balance sensitivity to atmospheric forcing in High Mountain Asia

Abstract The complex topography and size of High Mountain Asia (HMA) result in large differences in glacier mass-balance variability and climate sensitivity. Current understanding of these sensitivities is limited by simplifications in past studies’ model structure. This study overcomes this limitation by using a mass-balance model to investigate the climatic mass-balance variability and climate sensitivity of 16 glaciers covering major mountain ranges in HMA. Generally, glaciers in the southeast have higher mass turnover while glaciers at the margins of HMA show higher interannual mass-balance variability. All glaciers are most sensitive to temperature perturbations in summer. The climatic mass balance of 15 glaciers is most sensitive to precipitation perturbations in summer or spring and summer, even if the seasonal accumulation peak is not in summer. Only one glacier's mass balance (Chhota Shigri Glacier) is most sensitive to precipitation perturbations in winter. Glaciers with high mass turnover and high summer-precipitation ratio are more sensitive to temperature perturbations. Sensitivity experiments reveal that besides the non-linearity of mass-balance temperature sensitivity, mass-balance precipitation sensitivity is non-linear as well. Furthermore, resolving the diurnal cycle of albedo, (re)freezing and the differentiation between liquid and solid precipitation are important to assess climate sensitivity of glaciers in HMA.

Study on the characteristic of asphaltene-wax co-precipitation during gas injection of unconventional gas condensate reservoirs

The intensification of energy shortage has accelerated the development of unconventional oil and gas resources, during which complex problems of organic solid precipitation often occur. The precipitation behavior of organic solid such as asphaltene and wax play an important role in the optimization of reservoir production. However, there is still a lack of comprehensive understanding of the precipitation mechanism and interaction between asphaltene and wax, especially under high temperature and pressure. A self-designed precipitation apparatus based on backscattered light was utilized to achieve this objective. The effects of temperature range 30–120 ℃, pressure range 5–85 MPa, gas-oil ratio of 150，300 and 500 sm3/sm3 and injection gas of CH4, CO2 and N2 on organic solid precipitation in condensate oil-gas system were studied by physical simulation. The results revealed that asphaltene precipitated separately at high temperature, and asphaltene and wax co-precipitated at low temperature. Based on the observed precipitation behavior, a co-precipitation mechanism of asphaltene and wax under high-pressure conditions was proposed: Asphaltene particles precipitated first, providing nucleation sites for wax absorption, growth, and cross-linking as the pressure decreased. Moreover, the depressurization induced phase separation during oil and gas production resulted in the extraction of light components, reducing the solubility of wax and exacerbating reservoir damage caused by the precipitation of organic solid. Increasing the gas-oil ratio led to higher amounts of organic solid precipitation and shifted the pressure at which precipitation occurred. Furthermore, the miscibility of injection medium and condensate oil will also significantly affect organic matter precipitation, and the potential damage to the reservoir can be shown as follows: N2＞CO2＞CH4.

Numerical simulation of clogging of two types of emitters with similar properties

AbstractThe benefits of drip irrigation are numerous and include water savings, control of fertilizer applications, and improved water and energy use efficiency of irrigation. In these systems, the emitter is the most vulnerable component to clogging, which in critical states can cause a reduction in performance and shorten the life of the distribution system. It can also have several impacts on water, its economy, and its wastage. In the absence of adequate filtration and when the flow is through the narrow labyrinth channel of the emitter, clogging can be created by continuous deposition of solid particles, organic matter, dissolved salts, chemical precipitates, bacteria, and other impurities. It is obvious that it is impossible to physically visualize the hydraulic behavior of the flowing water in the labyrinths. However, due to the increasing performance of computational tools and simulation software, it is possible to simulate this flow through Computational Fluid Dynamics (CFD), which has become one of the main techniques for describing the flow and deposition of the solid phase inside the emitter. This study aims to numerically simulate the behavior and the flow of the fluid inside two emitters, widely used in the industry, with different types but approximately identical flow rates. The fluid takes in its flow an inert solid suspension of fixed concentration. One of the emitters is compensating‐pressure, and the other is non‐compensating‐pressure; the numerical simulation model used is the RNG κ‐ε two‐phase model. The results showed that the regions affected by clogging are mainly the corners of the labyrinth channel and the recirculation vortex zones. The trajectory field plot reveals that as the clogging increases, the serpentine fluid threads become thinner.

Effect of Mo addition on the microstructure and high-specific tensile strength of Fe–Mn–Al–Ni–C ferrous medium-entropy alloy

Molybdenum (Mo) is known to play various roles in ferrous materials, including promoting lattice distortion and forming different types of precipitates. In this study, Mo was added to the Fe–Mn–Al–Ni–C lightweight medium-entropy alloy system, and its effects on microstructure and tensile properties were investigated in comparison to the Mo-free counterpart. The addition of Mo retarded the kinetics of recrystallization and led to the precipitation of M6C-type carbides. In terms of tensile properties, the addition of Mo improved the strength of the alloy by enhancing solid solution strengthening and precipitation strengthening. In particular, the Mo-added alloy, annealed at 800 °C for 7.5 min, exhibited a yield strength of 1274 MPa and an ultimate tensile strength of 1550 MPa. This corresponds to a specific ultimate tensile strength of approximately 218 MPa g−1 cm3, along with a uniform elongation of ∼8.5 %. The Mo content in the solid solution and the presence of Mo-rich M6C-type carbides also contributed to high back stress hardening, which enhanced the alloy's ability for strain hardening and resulted in reasonable uniform elongation.

Alumina precipitate along dislocations in rutile single crystal of diffusion couple during cooling from 1200° to 1400°C

Diffusion couples of rutile and corundum single crystals were prepared and examined for the solid solution and precipitation of corundum in rutile during cooling. Alumina dissolves in rutile according to the following equation, Al2O3→2AlTi′+3OO+VO∙∙. In the sample air-quenched from 1200 °C, the supersaturated oxide ion vacancies, VO⋅⋅, reacted with the edge component of screw dislocation parallel to c axis to form helical dislocations, along which corundum was precipitated. When air-quenched from 1300 °C and 1400 °C, corundum was precipitated in the form of stacked rectangular loops. Corundum grains with eight lobes extending in the < 101 > directions were precipitated in the samples cooled at 10 °C/min from 1300 °C and 1400 °C. The solid solution reaction increased the volume of rutile single crystals and caused voids outside the reaction region at the interface. Both the corundum and rutile components of the voids also contributed to the solid solution reaction.

Quantitative analysis of recharge sources of different runoff types in the source region of Three River

This study systematically analyzed 2321 water samples to determine the spatiotemporal supply patterns of different runoff types in the source region of the Three Rivers from 2019 to 2021 using stable isotope tracing and endmember-element mixed runoff segmentation modeling. The results indicate that the δ18O and δD values of the tributary were more negative than those of the mainstream. The mainstream and tributary were primarily recharged by precipitation (61 %) and supra-permafrost water (53 %), respectively. Furthermore, with increasing altitude, the proportions of precipitation and glacial meltwater in the mainstream decreased and increased, respectively. Three river-water supply patterns were observed: (1) water was stored in glaciers and snow after solid precipitation events occurred, and the runoff was directly replenished by the melting of glaciers and snow; (2) various surface water bodies were mixed to recharge the supra-permafrost water, which replenished the runoff; and (3) lake water and wetlands were supplied by various surface water bodies, including surface runoff. These findings reveal the evolutionary mechanism of runoff in cold regions under climatic warming and provide crucial information for water resource management and sustainable development.

Intensification of aqueous mineralisation of CO2 with CaO containing industrial wastes in a modified airlift reactor

CO2 mineralisation is considered the safest storage medium for mitigating climate change. One of the challenges with the industrial demonstration of the mineralisation technology is reactor design. In the current study we demonstrate the use of draft tube based reactor for the mineralisation of CO2. The draft tube reactors show better performance as compared to the absence of draft tube at near ambient pressure for CO2 at different concentrations. The draft tube has been modified to increase the gas-liquid mass transfer rate by adding multi-orifice plates on top as well as increasing the solid precipitation in the reactor with a spiral flow arrangement at the bottom of the draft tube. At higher CO2 concentrations and near ambient pressures, the draft tube with modifications shows 2.5 fold enhancement in the overall rate as compared to draft tube without modifications. Additionally, at lower CO2 concentrations (i.e. near flue gas concentrations), the draft tube with modifications has better conversion capacity as compared to draft tube without modifications. This enhancement is due to the increased gas holdup and separation of solids in the draft tube with modifications. The precipitates obtained in the draft tube reactors show nanoparticles arranged in coral or mosaic arrangements as compared to the reactor without draft tube.

Mechanism of carbon nanotube growth in expanded graphite via catalytic pyrolysis reaction using carbores P as a carbon source.

Carbon nanotubes (CNTs) had potential applications in energy conversion and storage devices, and it could be prepared by expanded graphite loaded with catalyst at high temperature, however, the mechanism of carbon nanotube growth in expanded graphite need further confirmation. In this work, carbon nanotubes' in situ growth in expanded graphite (EG) were prepared via catalytic pyrolysis reaction using carbores P as a carbon source and Co(NO3)3•6H2O as a catalyst. The results of X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray spectroscope (EDS) indicated the carbon nanotubes could generate in, EG with the presence of carbores P as a carbon source and cobalt nitrate as a catalyst. More interestingly, the growth mechanism of carbon nanotubes could be concluded by the results of differential thermal analysis-thermogravimetry-mass spectrometry (DTA-TG-MS) and X-ray photoelectron spectroscopy (XPS) analysis. The pyrolysis products of carbores P were mainly hydrocarbon gas such as CH4 gas, which reacts with Co(NO3)3·6H2O catalyst to reduces CoOx to Co particles, then the carbon form pyrolysis was deposited the on the surface catalyst Co particles and, after continuous solid dissolution and precipitation, carbon nanotubes were at last generated in EG at last.

Characterization and strengthening mechanism of high-strength medium carbon spring steels

To develop higher strength spring steels with better performance for advanced automotive and transportation industries in line with the trend of lightweight, the strengthening mechanism of two practical 55SiCr and 55SiCrNbV spring steels, which represents plain and micro alloyed spring steels, has been investigated based on the systematic characterization of microstructures, hardness, and tensile test. The tensile strength and hardness were found to be correlated well in a linear relationship. Then the strengthening coefficients of C, Si, Cr and Mn were determined to quantify the solid solution strengthening. The strengthening mechanism of spring steels was found to be the summation of solid solution strengthening, grain refinement, dislocation, and precipitation strengthening, which agree well with the tensile test results. The strengthening mechanism could be used as guidance to develop next generation spring steels, which well explained the ultra-high strength spring steels over 2200 MPa class in the literature.

Effective Enhancement of Energy Density of Zinc-Polyiodide Flow Batteries by Organic/Penta-iodide Complexation.

Based on the ambipolar characteristics and high solubility of ZnI2, zinc-polyiodide flow batteries (ZIFB) have attracted attention as high-energy density flow batteries. However, due to the various oxidation products of iodide (I-) and the formation of iodine (I2) solid precipitates at the positive electrode, the limiting state-of-charge (SoC) of ZIFB has not been clearly defined. Herein, a clear definition of SoC in ZIFBs is given based on the thermodynamic relationship among I-(aq), I3-(aq), I5-(aq), and I2(aq) in the electrolyte. Conventional ZIFBs are limited by their maximum attainable SoC of 87%, at which the fully charged catholyte includes I-, I3-, and I5- ions at molar ratios of 49.6, 32.2, and 18.1%, respectively. Furthermore, two effective strategies to extend the maximum SoC are suggested: (1) increasing the formation constant (Keq) of I3- can raise the availability of I- for electrooxidation by suppressing I2 precipitation, and (2) promoting the production of higher-order polyiodides such as I5- can increase the oxidation state of the charged electrolyte. The addition of 5 vol % triethylene glycol (tri-EG) to the electrolyte increased Keq from 710 to 1123 L mol-1; this increase was confirmed spectrophotometrically. Tri-EG stabilized I5- ions in the form of the I5-/tri-EG complex, thereby converting the main oxidation product from I3- to I5-. The preferred electrochemical production of I5- in the tri-EG electrolyte was observed by electrochemical and computational analyses. As a result, the maximum attainable SoC was enhanced remarkably to 116%, yielding molar ratios of I-, I3-, and I5- ions of 9.1, 11.2, and 79.7%, respectively. This SoC extension effect was confirmed in the ZIFB flow cell with stable charge-discharge cycling at the SoC 120% limit, demonstrating the highest energy density, 249.9 Wh L-1, among all reported ZIFBs.

Precipitation behavior of hexagonal carbides in a C containing intermetallic γ-TiAl based alloy

Intermetallic γ-TiAl based alloys are currently used as structural materials in high-temperature applications such as turbocharger wheels, valves and turbine blades. Adding C yields solid solution and precipitation hardening of the TiAl alloys, which raises their service temperature. Within this work, the effect of C on the TNM alloying system is analyzed by complementary differential scanning calorimetry measurements and selected heat treatments in conjunction with detailed electron microscopy analysis. This allowed the determination of the transition temperatures and revealed the precipitation onset of hexagonal Ti2AlC carbides between 1450 °C and 1475 °C. The precipitation kinetics of the carbides were further investigated by laser scanning confocal microscopy and revealed a preferred and steady growth in the length direction. Further, orientation relationships between the TiAl phases and the carbides from Blackburn and Burgers type could be determined by electron back-scatter diffraction. The results of this study provide a better understanding of the effect of C addition on the TNM alloy and thus enable further improvement of the alloying design process.

Mercury concentration in the snow cover of the city of Khabarovsk

The research reveals results of studies of the total mercury content in the snow cover of Khabarovsk in winter period 2021-2022. Researchers highlight a connection between mercury and non-soluble residue, with minor transition into soluble phase. The total mercury content in the non-soluble residue ranged from 0.3 to 1.4 mg/kg. On the northern border of the Bolshekhekhtsirsky Reserve, area with high content of quicksilver (3 mg/kg) was found, which exceeds the maxi-mum permissible concentration by 1.4 times. Authors consider that high concentration of quicksilver may be a result of short-term local pollution and do not exclude cross-border origin of it. Content of mercury as a part of solid atmospheric precipitation on the Earth’s surface in this area is 37.5 µg/m2, with average values of 10-18 µg/m2. The maximum content of mercury (73.9 µg/m2) was found nearby CHP-3 area. The reason is a high concentration of combustion products in snow cover. The amount of solid atmospheric precipitation in the area of CHP-1 also significantly exceeded the average values, but this did not lead to an increase in the total amount of mercury that reached the surface. The minimum concentration of quicksilver was found in the embankment park area of the city - 3.2 µg/m2.