Concentrations Of Inorganic Ions Research Articles

Optimized process for the odd‑carbon volatile fatty acids (OCFA) directional production: Anaerobic co-digestion of disused grease with sludge by anaerobic sequencing batch reactor

Odd‑carbon volatile fatty acids (OCFA) are a kind of desired carbon source for biological nitrogen and phosphorus removal (BNR) and the synthesis of polyhydroxyalkanoates (PHAs). This study explored and realized the directional production of OCFA continuously and steadily in the process of anaerobic co-digestion with disused grease and aerobic sludge. For that purpose, the anaerobic sequencing batch reactor (ASBR) was performed under 9.64 ± 0.5 g/L of mixed liquid suspended solids (MLSS) and 7.14-d hydraulic residence time (HRT) conditions. On focus, the initial NH4+ concentration of each cycle was adjusted to enrich propionic acid and maintain the stable operation of ASBR for the directional production of OCFA. Experimental results demonstrated that this process facilitated the enrichment of associated propionic acid-generating bacteria with the maximal OCFA yields of 3889.24 mg/L. Volatile fatty acids (VFAs) yield (2240.06–2941.12 mg/L), OCFA/VFAs (86.48–90.95%) and various ecological conditions gradually stabilized during the operation of ASBR. Moreover, the concentration of inorganic ion: PO43− (22.65–28.15 mg/L) and NH4+ (63.01–108.94 mg/L) were within the regulatory range available for downstream processes. Therefore, the ASBR process can be used for the continuous and stable production of OCFA.

Tolerance of glacial-melt stoneflies (Plecoptera) and morphological responses of chloride cells to stream salinity

Aquatic insects within glacial-melt streams are adapted to low dissolved inorganic ion concentrations. Increases in ion concentrations in glacial-melt streams are predicted with increasing air temperatures, which may impact future aquatic insect survival in these streams. We hypothesized that stonefly (Plecoptera) naiads from glacial-melt streams acclimated to different conductivity would differ in survival, median lethal concentrations, and chloride cell responses to elevated conductivity above that expected in our study streams. We conducted field bioassays in remote glacial-melt streams in southwestern China in 2015 and exposed representative stonefly naiads (Chloroperlidae, Nemouridae, Taeniopterygidae) from stream sites differing in conductivity to experimental conductivity ranging from 11 to 20,486 μS/cm for up to 216 h. We examined survivorship, calculated 96-h median lethal concentrations, and measured chloride cell responses with scanning electron microscopy. Chloroperlidae survival after 120 and 216 h did not differ (P > 0.05) among conductivity treatments. The combined Nemouridae/Taeniopterygidae survival after 120 and 216 h was the least (P < 0.05) in conductivity treatments >16,349 μS/cm. Taeniopterygidae survival after 120 h was also the least (P < 0.05) in conductivity treatments >16,349 μS/cm. The 96-h median lethal concentrations did not differ (P > 0.05) between the combined Nemouridae/Taeniopterygidae group (2306 μS/cm) and Taeniopterigydae (2002 μS/cm) and were lower (P < 0.05) than the 96-h median lethal concentration for Chloroperlidae (8167 μS/cm). Chloroperlidae caviform cell number, density, and area decreased (P < 0.05) with increasing conductivity. Taeniopterygidae caviform cell count decreased (P < 0.05) with increasing conductivity, but cell density and area did not. Chloroperlidae and Taeniopterygidae coniform cell characteristics and Nemouridae bulbiform cell characteristics were not affected by conductivity. Our results suggest that Chloroperlidae, Nemouridae, and Taeniopterygidae from glacial-melt streams in China may be able to tolerate moderate increases in conductivity (i.e., 100 to 200 μS/cm).

Deciphering the spatial fouling characteristics of reverse osmosis membranes for coal chemical wastewater treatment

Reverse osmosis (RO) membranes are widely used in the advanced treatment of coal chemical wastewater. Nevertheless, membrane fouling is an intractable concern which decreases permeate flux, impairs water quality and increases energy consumption. Mapping the spatial distribution of membrane fouling and identifying the key factor for flux decline are of great significance for membrane fouling control. In this study, each membrane sample from first-stage and second-stage RO membrane elements was divided into 12 regions for autopsy. The results showed that membrane fouling at both stages was exacerbated from the feed end to the concentrate end owing to the concentrating effect and concentration polarization. Organic and inorganic foulants mainly deposited at the concentrate end and near the permeate tube, whereas biofouling did not show a regular distribution pattern. Biofouling was the paramount contributor to flux decline, whether at the first stage (40%) or the second stage (27%). However, the effect of inorganic fouling became prominent at the second stage due to the higher concentration of inorganic ions and stronger interactions with other foulants. Suggestions for membrane fouling control strategies include reinforced anti-biofouling countermeasures at the lead element, anti-scaling schemes after the first stage, and customized feed spacer and membrane designs for specific fouling at different locations.

Seasonal variations, temperature dependence, and sources of size-resolved PM components in Nanjing, east China

Size-segregated ambient particulate matter (PM) samples were collected seasonally in suburban Nanjing of east China from 2016 to 2017 and chemically speciated. In both fine (< 2.1 µm, PM2.1) and coarse (> 2.1 µm, PM>2.1) PM, organic carbon (OC) accounted for the highest fractions (26.9% ± 10.9% and 23.1% ± 9.35%) of all measured species, and NO3− lead in average concentrations of water-soluble inorganic ions (WSIIs). The size distributions of measured components were parameterized using geometric mean diameter (GMD). GMD values of NO3−, Cl−, OC, and PM for the whole size range varied from < 2.1 µm in winter to > 2.1 μm in warm seasons, which was due to the fact that the size distributions of semi-volatile components (e.g., NH4NO3, NH4Cl, and OC) had a dependency on the ambient temperature. Unlike OC, elemental carbon (EC), and elements, NH4+, NO3−, and SO42− exhibited an increase trend in GMD values with relative humidity, indicating that the hygroscopic growth might also play a role in driving seasonal changes of PM size distributions. Positive matrix factorization was performed using compositional data of fine and coarse particles, respectively. The secondary formation of inorganic salts contributing to the majority (> 70%) of fine PM and 20.2% ± 19.9% of speciated coarse PM. The remaining coarse PM content was attributed to a variety of dust sources. Considering that coarse and fine PM had comparable mass concentrations, more attention should be paid to local dust emissions in future air quality plans.

Physical Responses of Pinctada fucata to Salinity Stress

This study was conducted to understand the changes of physiological and biochemical indexes of black and red shell Pinctada fucata under acute high and low salt stress. In this study, the salinity of 35‰ was used as the control, while the salinities of 20 and 50% salinity were used as the low and high salt treatment groups, respectively. The osmotic pressure (OSM) and ion concentration in the hemolymph, Na+-K+ -ATPase (NKA) activity and respiratory metabolism in gills, and antioxidant and immune (non) enzymes in the hepatopancreas of P. fucata with two shell colors were compared and analyzed at the time periods of 1.5 and 3 h post-salinity stress. The results showed that the OSM and inorganic ion (Na+, Ca2+, and Cl–) concentration in the hemolymph of the black and red P. fucata increased significantly with the increase of salinity after the time periods of 1.5 and 3 h. At 3 h, the black P. fucata NKA activity decreased significantly with the increase of salinity, while red P. fucata reached the highest value at high salinity. The succinate dehydrogenase (SDH) and lactate dehydrogenase (LDH) activities of red P. fucata showed U-shaped and inverted U-shaped distributions with the increase of salinity after 1.5 h, respectively. With the increase of salinity, the phenoloxidase (POX) activity of red and black P. fucata showed inverted U-shaped and U-shaped distributions, respectively. The contents of glutathione (GSH) and vitamin C (VC) in black P. fucata decreased significantly with the increase of salinity at 1.5 and 3 h. Red P. fucata GSH and VC reached their maximum value in the 1.5-h low salinity group and 3-h high salinity group. The vitamin E (VE) content in black P. fucata increased significantly with the increase of salinity at 1.5 h, and reached the maximum at 3 h in the control group. Red P. fucata VE reached the maximum at 1.5 and 3 h in the control group. The results obtained from the present study revealed that the sensitivity of P. fucata to salinity varied in shell color. Compared to black P. fucata, red P. fucata responds more quickly to sharp salinity changes, thereby reducing more likely damage. Compared with a high salt environment, P. fucata was more adaptable to the changes of acute low salt environment. The results obtained from the present study provide the physical references for subsequent selective breeding of this species.

The hatching of cereal cyst nematode (Heterodera avenae) in response to different inorganic ions

Cereal cyst nematode is a major pest of small grain cereals, which causes huge yield losses to crops in China and other parts of the world. In this study, the effects of five inorganic ion concentrations on egg hatching of Heterodera avenae were studied. Results revealed that ZnCl2 and FeCl3 promoted hatching of induced and natural diapausing eggs. The cumulative hatching rates of eggs were 49 % and 13 % at 30 mM ZnCl2 and 10 mM FeCl3, respectively, which were higher than those of other treatments. The hatching ability promoted by ZnCl2 is greater than by FeCl3. Diapause induced eggs in ZnCl2 continued to hatch after 10 days; however, those in FeCl3 mainly hatched in the first two weeks. ZnCl2 had obvious stimulating effects on the hatching of natural diapause and non–diapause free eggs at 15 and 30 mM concentrations. FeCl3 promoted the hatching of natural diapause eggs; howevr, it inhibited hatching of non–diapause free eggs. Conversely, different concentrations of inorganic ions did not have any stimulatory effect on white female eggs. In the nematode life cycle, hatching is the critical stage because juveniles may be infected. The results of this study provide useful information the use of new fertilizers (including promoted hatching inorganic ions) applied before planting for controlling nematode diseases caused by H. avenae.

Solute selectivity, separation mechanism and application performance of freezing wastewater treatment: Focus on air cooling and direct contact cooling

Freezing separation is a green and high efficient wastewater treatment technology. Considering the problems of freezing methods, treatment specificity and relative energy efficiency, an air cooling device and a direct contact cooling device were developed. The removal rates, ice-forming rates, and energy efficiency of different freezing methods were investigated with different concentrations of inorganic salt ions, small molecule organic matter, and organic polymer solutions. The results showed that there was solute selectivity in freezing separation, while the separation effects increased in decreasing solute concentration, with higher solute removal rates for inorganic salt solutions and small molecule organics and lower removal efficiency for high molecule organics, and there was the highest potential application value of copper contact column by comparing the removal rates and composition ratios. In addition, stirring enhanced the solute removal rate significantly, which affected the concentration gradient distribution and the microenvironment of the ice-forming interface. In the treatment of condensate wastewater from MVR(Mechanical Vapor Recompression) system and dye wastewater with high salt and high organic, the results showed that the removal rates reached 70% and 50% respectively, and it provided reference to the application of freezing separation in practical water treatment.

Size Distributions and Seasonal Variations of Water-Soluble Inorganic Particulate Matter at a Suburban Site in Nanjing, China

Abstract Size-resolved aerosol mass concentrations and concentrations of inorganic water-soluble ions (WSIs) were measured in four seasons, from December 22, 2016 to November 28, 2017, in Nanjing, ...

Hydroxyapatite Particles from Simulated Body Fluids with Different pH and Their Effects on Mesenchymal Stem Cells.

Bone-like hydroxyapatite (HAp) has been prepared by biomimetic synthesis using simulated body fluid (SBF), mimicking inorganic ion concentrations in human plasma, or 1.5SBF that has 1.5-times higher ion concentrations than SBF. In this study, the controllable preparations of HAp particles from 1.5SBF with different pH values were examined. The particles obtained as precipitates from 1.5SBF showed different morphologies and crystallinities depending on the pH of 1.5SBF. Micro-sized particles at pH 7.4 of 1.5SBF had a higher Ca/P ratio and crystallinity as compared with nano-sized particles at pH 8.0 and pH 8.4 of 1.5SBF. However, a mixture of micro-sized and nano-sized particles was obtained from pH 7.7 of 1.5SBF. When Ca2+ concentrations in 1.5SBF during mineralization were monitored, the concentration at pH 7.4 drastically decreased from 12 to 24 h. At higher pH, such as 8.0 and 8.4, the Ca2+ concentrations decreased during pH adjustment and slightly decreased even after 48 h. In this investigation at pH 7.7, the Ca2+ concentrations were higher than pH 8.0 and 8.4.Additionally, cytotoxicity of the obtained precipitates to mesenchymal stem cells was lower than that of synthetic HAp. Controllable preparation HAp particles from SBF has potential applications in the construction of building components of cell scaffolds.

The isotopic patterns and source apportionment of nitrate and ammonium in atmospheric aerosol

Nitrate (NO3-) and ammonium (NH4+) are the major components in inorganic aerosol. However, their sources and formation processes remain unclear. This study conducted a year-round field measurement of TSP, PM2.5 and PM1.0 in five different sites in the Beijing-Tianjin-Hebei (BTH) region to determine the concentrations of water-soluble inorganic ions (WSIIs) and the isotopic compositions of inorganic nitrogen (δ15N-NH4+, δ15N-NO3-, and δ18O-NO3-). The results showed the highest concentration of WSIIs in winter and lowest in summer. δ15N-NO3-, δ18O-NO3-, and δ15N-NH4+ were in the range of -6.1–18.2, 52.2–103.8, and -28.7–36.2‰, respectively. The seasonal variations of δ15N-NO3- and δ15N-NH4+ were an indication of relative contributions of the main sources and effects of meteorological conditions. The source apportionment identified fossil fuel combustion (38.2–50.6%), agricultural emissions (18–24.7%), biomass burning (16.3–22.7%), and road dust/soil (8.7–23.4%) were the main sources of inorganic aerosols. The local sources and regional migration contributed to the level of inorganic aerosol pollution. In winter, the aerosol in the BTH region was affected by the air mass from the northwest. While in spring and summer, the air mass was mainly from the South China. The low temperature and high relative humidity favored to the formation of inorganic nitrogen aerosol, and solar radiation affected the formation processes of inorganic aerosols by changing the oxidation pathway of NO3- and accelerating the volatilization and dissociation of ammonium nitrate (NH4NO3). This study discovered the main source contributions of inorganic nitrogen aerosol using N and O isotopes composition, and the obtained information has a great importance in understanding the effects of meteorological conditions on formation and the contribution of regional transport.

Chemical characteristics of size-resolved fog water at an urban site in Nanjing and the summit of Mt. Lu, East China

The chemical characteristics of fog water are closely related to the droplet size. This study used a three-stage Caltech Active Strand Cloud Collector (CASCC) to collect 170 size-resolved fog samples from eight fog events in the winter of 2013–2017 at an urban site in Nanjing and the summit of Mt. Lu. The pH, electrical conductivity (EC), and inorganic ion concentration were analyzed, and the sources of pollutants in size-dependent droplets were discussed according to the local emission source type. The pH, EC, total ion concentration (TIC), and ion composition of fog water at Nanjing were dependent on the droplet size. The TIC of fog water at Nanjing was approximately 10 times that measured at Mt. Lu. The concentration of different chemical species in the droplet was also size-dependent: Ca2+ concentration was higher in larger droplets with the diameter (D) ≥ 22 μm, whereas SO42−, NO3−, and NH4+ concentrations were higher in smaller droplets with D ranging 4–16 μm. The ion concentration of fog water at Mt. Lu first decreased then increased as the fog developed. Owing to the faster drop rate of larger droplets, coarse particles (2.5–10 μm) exhibited a faster response to fog removal, and the final mass concentration of fine particles (<2.5 μm) decreased the most due to competition between deposition and gravity. Different pollution sources exhibited different contribution rates to the chemical components of size-dependent droplets. Soil sources mainly affected the Ca2+ content of large droplets, whereas industrial sources and vehicles affected the NO3− and SO42− concentrations of medium and small droplets. Soil sources, industrial sources, and vehicles were the main sources of fog water at the urban site in Nanjing, whereas industrial sources, vehicles, soil sources, biomass combustion, and secondary aerosols were the main sources of fog water at the summit of Mt. Lu.

Chemical Components and Sources of PM2.5 and Their Evolutive Characteristics in Zhengzhou

To explore the main sources of PM2.5 and the characteristics of seasonal differences in Zhengzhou, PM2.5 sampling was conducted in 2019 and the concentrations of inorganic water-soluble ions, carbon components, and various elements were analyzed. Results showed that the average mass concentration of PM2.5 in 2019 was (67.0±37.2) μg ·m-3 with the highest concentration in winter and the lowest in summer. The main components of PM2.5 were nitrate, ammonium, sulfate, organic matter, crustal matter, and elemental carbon. In spring and autumn, PM2.5 was greatly affected by crustal matter and elemental carbon, and In summer, concentrations were mainly affected by sulfate. In winter, the concentrations of organic matter and nitrate increased significantly, produced by photochemical reactions in summer and aqueous-phase reactions under high humidity in winter. Carbonaceous aerosols were greatly influenced by automobile exhaust emission, coal combustion, and biomass combustion. Source apportionment showed that secondary sources were the greatest contributors in all four seasons, particularly in in winter (56.5%). Among the primary sources, the proportion of dust in spring (15.2%) and autumn (11.4%) was slightly higher, and the contribution of motor vehicle pollution was the largest (12.3%) in summer. In winter, PM2.5was greatly affected by coal combustion (13.2%). From 2014 to 2019, PM2.5 in Zhengzhou increased annually under the influence of secondary sources. The contribution of industrial sources, biomass combustion sources, and coal combustion sources exhibited a downward trend over this period.

Muscle-inspired ion-sensitive hydrogels with highly tunable mechanical performance for versatile industrial applications

Human muscles are notably toughened or softened with specific inorganic ions. Inspired by this phenomenon, herein we report a simple strategy to endow hydrogels with comparable ion-responsive mechanical properties by treating the gels with different ionic solutions. Semi-crystalline poly(vinyl alcohol) hydrogels are chosen as examples to illustrate this concept. Similar to muscles, the mechanical property of hydrogels demonstrates strong dependence on both the nature and concentration of inorganic ions. Immersed at the same salt concentration, the hydrogels treated with different ionic solutions manifest a broad-range tunability in rigidity (Young’s modulus from 0.16 to 9.6 MPa), extensibility (elongation ratio from 100% to 570%), and toughness (fracture work from 0.82 to 35 MJ m−3). The mechanical property well follows the Hofmeister series, where the “salting-out” salts (kosmotropes) have a more pronounced effect on the reinforcement of the hydrogels. Besides, the hydrogels’ mechanical performance exhibits a positive correlation with the salt concentration. Furthermore, it is revealed both the polymer solubility from amorphous domains and polymer crystallinity from crystalline domains are significantly influenced by the ions, which synergistically contribute to the salt-responsive mechanical performance. Benefitting from this feature, the hydrogels have demonstrated promising industrial applications, including tunable tough engineering soft materials, anti-icing coatings, and soft electronic devices.

A Comparative Study on Low and High Salinity Tolerance of Two Strains of Pinctada fucata

This study compares salinity tolerance between red and black shell Pinctada fucata salinity stress of 20 and 50‰, while 35‰ was used as a control. The hemolymph osmotic pressure, inorganic ion concentration, the activities of Na+-K+ -ATPase, respiratory metabolism related enzymes and liver tissue antioxidant related enzymes were measured at 12 and 24 h after salinity stress. The osmotic pressure and inorganic ion concentration of hemolymph of two strains P. fucata increased significantly with the increase of salinity. The activity of Na+-K+ -ATPase of red P. fucata only decreased under low salinity at 24 h, and was significantly higher than that the control under low salinity at 12 h and high salinity at 12 and 24 h. The succinate dehydrogenase (SDH) activities of the P. fucata treatment groups were significantly higher than those the control at 12 h. The lactate dehydrogenase (LDH) activity increased significantly with salinity at 12 h. and the black P. fucata LDH activity was significantly higher than the control at 24 h, while the LDH activity of red P. fucata was significantly lower than that the control in 50‰ salinity. The superoxide dismutase (SOD) activity of black P. fucata was significantly lower than that the control, while that of red P. fucata was significantly higher than that the control within 24. At 12 h, the catalase (CAT) activity of red P. fucata increased significantly with salinity, but decreased significantly with salinity at 24 h. The CAT activity of black P. fucata was highest at 24 h under low salinity. Glutathione peroxidase (GSH-Px) and alkaline phosphatase (AKP) activities of red P. fucata were significantly higher than those the control under low or high salinity. At high salinity for 24 h, the GSH-Px activity was lowest in black P. fucata, AKP activity was highest. The present study indicates that the physical responses of P. fucata to the salinity stress vary with shell colors. The red P. fucata can quickly respond positively to the change of environmental salinity and reduce the damage caused by the change of environmental salinity.

Contributions of aerosol chemical composition and sources to light extinction during haze and non-haze days in Taiyuan, China

To better understand the causes of visibility degradation in Taiyuan, the concentrations of PM1.5 and main chemical compositions were analyzed during the period from July 28, 2014 to April 26, 2015. The average concentration of PM1.5 during the sampling period was 107.6 ± 51.0 μg/m3. The concentrations of secondary inorganic water-soluble ions (SIA, the sum of SO42−, NO3− and NH4+), OC and EC were 31.0 μg/m3, 14.6 μg/m3 and 6.0 μg/m3, accounting for 28.8%, 13.5% and 5.6% of PM1.5, respectively. Light extinction coefficients (bext) were estimated by the revised US Interagency Monitoring of Protected Visual Environments (IMPROVE) equation. (NH4)2SO4 (48.7%) was the largest contributor to bext in summer, while the contribution of organic matter (OM) to bext was the highest in spring (25.0%) and winter (42.0%). Compared with non-haze days in summer and winter, the contributions of (NH4)2SO4 and NH4NO3 to bext during haze days increased, while the contributions of OM, EC, fine soil and coarse matter (PM1.5-10) decreased. Air masses from the southern areas had the largest bext and contribution of (NH4)2SO4 in summer and winter. The results of source apportionment by positive matrix factorization model found that secondary sulfate, secondary nitrate, coal combustion, vehicle emission, fugitive dust, biomass burning were the main sources to bext in Taiyuan. Secondary sulfate (81.7%) and coal combustion (43.1%) were the largest contributors to the bext in summer and winter during haze days, respectively. The results of our study could improve the understanding of the major sources that affect visibility degradation in Taiyuan.

Drivers of Organic Molecular Signatures in the Amazon River

AbstractAs climate‐driven El Niño Southern Oscillation (ENSO) events are projected to increase in frequency and severity, much attention has focused on impacts regarding ecosystem productivity and carbon balance in Amazonian rainforests, with comparatively little attention given to carbon dynamics in fluvial ecosystems. In this study, we compared the wet 2012 La Niña period to the following normal hydrologic period in the Amazon River. Elevated water flux during the La Niña period was accompanied by dilution of inorganic ion concentrations. Furthermore, the La Niña period exported 2.77 Tg C yr−1 more dissolved organic carbon (DOC) than the normal period, an increase greater than the annual amount of DOC exported by the Mississippi River. Using ultra‐high‐resolution mass spectrometry, we detected both intra‐ and interannual differences in dissolved organic matter (DOM) composition, revealing that DOM exported during the dry season and the normal period was more aliphatic, whereas compounds in the wet season and following the La Niña event were more aromatic, with ramifications for its environmental role. Furthermore, as this study has the highest temporal resolution DOM compositional data for the Amazon River to‐date we showed that compounds were highly correlated to a 6‐month lag in Pacific temperature and pressure anomalies, suggesting that ENSO events could impact DOM composition exported to the Atlantic Ocean. Therefore, as ENSO events increase in frequency and severity into the future it seems likely that there will be downstream consequences for the fate of Amazon Basin‐derived DOM concurrent with lag periods as described here.

Characteristics of Aerosol and Effect of Aerosol-Radiation-Feedback in Handan, an Industrialized and Polluted City in China in Haze Episodes

In order to investigate the chemical characteristics of aerosol pollution including PM1 and PM2.5 in Handan, the offline sampling campaign was conducted and the concentrations of total water-soluble inorganic ions (TWSI), carbonaceous components (OC and EC) were analyzed. The average concentrations were 88.5 μg/m3 for PM1 and 122 μg/m3 for PM2.5, and the corresponding ratios of PM1 versus PM2.5 on non-pollution, mild-moderate pollution and heavy pollution were 0.67, 0.70 and 0.77, respectively. TWSI and OC accounted for 43.2% and 15.4% in PM1, 41.8% and 16.0% in PM2.5. Secondary components in PM2.5 and PM1 increased with heavy pollution, SNA (SO42−, NO3− and NH4+) was enriched in PM1 but SOC (Secondary Organic Carbon) was more enriched in PM1–2.5. Furthermore, for evaluating the effect of aerosol feedback the WRF-Chem model was applied to identify the aerosol-radiation interaction of aerosol feedback influence on the PM2.5 concentration and various meteorological factors in Handan. The results indicated that the aerosol radiative effects will result in an average 32.62%(36.18 W/m2) decrease in downward short wave flux at ground surface (SWDOWN), an average 17.52% (39.15 m) and 0.16% (0.44 K) decrease in planetary boundary layer height(PBLH) and surface temperature (T2). The wind speed at 10 m (WS) and relative humidity (RH) will be increased by about 4.16%(0.11 m/s) and 1.89% (0.78%), respectively.

Analysis of the Water Quality of the Ishim River within the Akmola Region (Kazakhstan) Using Hydrochemical Indicators

For the first time in scientific literature, this work addresses the current situation of the Ishim River water quality in the Akmola Region (Northern Kazakhstan). This work uses environmental monitoring techniques to analyze the current state of surface waters in the river. The content of main ions, biogenic and inorganic ions, heavy metals, organic impurities in seasonal and annual dynamics have been studied. Results show that, despite the tightening of requirements for wastewater discharge into the Ishim River basin, a number of water quality indicators did not fulfill the regulatory requirements for surface water bodies during 2013–2019. It has been identified that the greatest pollution in the Ishim River is brought by enterprises of the Karaganda-Temirtau technogenic region, located in the upper reaches of the river. Future water quality monitoring is needed and should include increasing the number of sampling locations and the sampling frequency in order to characterize the spatial and temporal variability of hydrochemical parameters and allow a comprehensive monitoring of legally fixed water quality parameters/indicators.

Chemical speciation of iron in the euphotic zone along the Kuroshio Current

The distributions of dissolved iron (DFe) and organic iron-binding ligands (LFe) in the Kuroshio Current and its neighboring waters were elucidated from four cross-sectional surveys from the eastern coast of Taiwan to Sagami Bay. The Kuroshio surface water was characterized by a high salinity, low concentration of DFe, high concentration of LFe, and low fluorescence of humic-like substances, in comparison to the neighboring waters. The neighboring waters of the Kuroshio can be categorized into two types: the East China Sea water and coastal water. The East China Sea water was found near the Okinawa Trough, and characterized by a steep vertical gradient of DFe concentration, almost as low as that in the Kuroshio within the surface mixed layer, but reached ~0.5 nM below the mixed layer. Coastal water was observed on the southern coast of Japan, and its DFe concentration was high throughout the upper 200 m. The concentration of LFe in the Kuroshio water was significantly higher at 10-m depth than in the deeper layers. This suggests that humic-like substances, which are a major component of LFe in estuarine and deep waters, play a relatively minor role in the Kuroshio surface waters. Mixing with coastal waters can increase the concentration of bioavailable inorganic ferric ions in the Kuroshio surface water in two ways, by increasing the DFe concentration and decreasing the LFe concentration.

Particles liquid water and acidity determine formation of secondary inorganic ions in Urumqi, NW China

Secondary atmospheric pollutants are an important component of the particles found in Urumqi city, China, Further, secondary inorganic aerosols, in particular, increase significantly during the winter heating period. In this study, samples collected from October 2017 to August 2018 from Urumqi were analyzed. Results showed that the average concentration of water-soluble inorganic ions (WSIs) in the heating period (86.9 ± 31.1 μg·m−3) was significantly higher than that in the non-heating period (14.1 ± 8.67 μg·m−3). SNA (SO42−, NO3−, NH4+) accounted for 90.7% of the total WSIs (TWSIs) in the heating period. Simulations revealed that the in situ pH (3.1) was higher in the heating period than that in non-heating period (0.66) when they were calculated by the aerosol thermodynamic model. The particles were found to be acidity during the entire period. The liquid water content of the particulates (LWC) was found to higher in the heating period (55.5 ± 51.8 μg·m−3) than the non-heating period (21.3 ± 40.3 μg·m−3). The average nitrogen oxidation rate (NOR) and sulfur oxidation rate (SOR) were 0.16 and 0.36, respectively, indicating a significant secondary formation of nitrate and sulfate in the atmosphere of Urumqi. Further analysis indicated that sulfate was significantly affected by the LWC and acidity of the particulates; nitrate was produced under ammonia-rich conditions in Urumqi, and the LWC facilitated the production of nitrate. This study provides information about the formation of secondary sulfate and nitrate aerosols during different periods in suburban Urumqi.