Removal Treatment Research Articles

Regeneration of forest floor-grown seedlings of Sakhalin fir can be promoted through shading by shelter trees

ABSTRACT Natural regeneration of forest-floor seedlings of Sakhalin fir (Abies sachalinensis) is expected to contribute to low-cost afforestation. However, removal of canopy trees often causes photoinhibitory damage in forest-floor seedlings of Sakhalin fir as a typical shade-tolerant species. In the present study, we investigated factors related to solar radiation influencing survival rate and growth of Sakhalin fir seedlings after a canopy tree cutting in 62-year-old forest plantations. Survival rates, derived from aerial photographs taken by an unmanned aerial vehicle, could be predicted by the maximum consecutive direct solar radiation and shade period calculated from the sun track simulated by hemispheric photographs. Needle shedding rate of old shoots, which were developed under shade, increased with increasing daily integrated direct solar radiation in the first summer after the winter cutting of canopy trees. Conversely, growth rates of current-year-old shoots in the second summer after the winter cutting of canopy trees decreased with increasing daily integrated direct solar radiation. Needle shedding might suppress the growth rate of current-year-old shoots in the second summer, possibly due to the decreased nitrogen supply from the old needles. Thus, shading achieved by topography (e.g. north-faced slope) and retained shelter trees would be of relevance for the natural regeneration of forest-floor seedlings of Sakhalin fir, a typical shade-tolerant species.

Trunk hair removal treatment with diode laser 810 nm in men population.

In the last years, hair removal has been one of the most common treatments performed for aesthetic purposes, especially in women. Nevertheless, even if it is less popular, the demand within men population has risen. The study aimed to assess the acceptability of the diode 810 nm treatment for hair removal on the back and chest area in men thanks to the speed of treatment and the absence of undesirable effects. For this study, 20 patients were treated for hair removal. They were men with a mean age of 30.5 (±7.3). They underwent 4 treatment sessions at 40-day intervals on the trunk (chest and back area). Patients ranged between a Fitzpatrick phototype I (20%, 4/20) to IV (15%, 3/20) (40% were type II and 25% type III). Moreover, patients were asked to report pain intensity sensation with a visual analogue scale. Overall, in the study population, a hair reduction of 80.6% (±2.8) was registered in the treated areas. The device described in this study was demonstrated to be highly efficient in extended body areas and on difficult-to-treat hair follicles like on the back and chest in the men population.

Soil disturbance, amelioration and rehabilitation affect forest growth, health, soil carbon and chemistry on five long-term soil productivity (LTSP) sites in southeastern British Columbia

Soil disturbance amelioration affected tree survival, growth, health, mineral soil chemistry, and their covariation on five Long-Term Soil Productivity (LTSP) sites in southeastern British Columbia. The two most different LTSP treatments (baseline disturbance of no compaction / all organic matter left, versus most severe of heavy compaction / forest floor removed) were compared to five amelioration treatments: rehabilitation of most severe LTSP treatment (soil tillage with or without incorporation of removed forest floor [Rehab + FF]), root disease (Armillaria ostoyae (Romagn.) Herink) amelioration treatments (stump removal or biological with Hypholoma fasiculare), and enhancement of soil organic matter (tilling extra forest floor into mineral soil). Treatment significantly (p < 0.05) affected 10-year mineral soil carbon, nitrogen, sulfur, mineralizable nitrogen, and potassium, which were lower on forest floor removal treatments and higher on forest floor addition treatments (27 to 97% of baseline versus 78 to 183% of baseline, respectively). Western white pine (Pinus monticola Dougl. ex D.Don) 15-year productivity (m3/ha) was significantly affected by treatment (Rehab + FF yielding a 10 fold increase in productivity versus the poorly growing baseline treatment), with treatment also significant when total disease was a covariate and for average and total volume when mineral soil Ca:Al ratio was a marginally significant (p < 0.1) covariate, and for survival when the incidence of total disease or white pine blister rust (Cronartium ribicola) were significant covariates; or with mineral soil C:N ratio as a significant covariate. The incidence of blister rust and total disease were significantly influenced by treatment when C:N was a significant covariate. For 20-year lodgepole pine (Pinus contorta Dougl. Ex Loud) there were no direct relationships apparent, but western gall rust (Endocronartium harknessii) had treatment significant when total sulfur was a significant covariate. Fifteen- and twenty-year Douglas-fir (Pseudotsuga menziesii var. glauca [Beissn.] Franco) had no significant relationships. Results demonstrate that restoring or adding extra organic matter (forest floor) into mineral soil increased soil carbon and related nutrients and can increase above ground carbon (forest productivity). Conversely, removing forest floor lowered mineral soil carbon and generally lowered tree volume. Varied effects due to growth limiting factors like frost and competing vegetation affected results on a few plots. Recommendations include leaving or enhancing organic matter onsite for soil carbon, nutrients, forest health and site productivity. Further analysis with the larger LTSP dataset and ongoing monitoring is encouraged to determine if the results persist in the long-term and to better understand the significant covariate relationships.

A critical analysis of various post-harvest arsenic removal treatments of rice and their impact on public health due to nutrient loss.

Rice (Oryza sativa L.) is particularly susceptible to arsenic (As) accumulation. Currently, to decrease the level of As accumulated in rice, various post-harvest methods, i.e., polishing, parboiling, pH-dependent soaking, washing, and cooking at different rice-to-water ratios (r/w), are being focused, because it removes significant amount of As from rice grain. Depending upon the rice variety and type, i.e., rough (with husk), husked (without husk/brown), or polished rice, these methods can remove 39-54% As by parboiling, 38-55% by polishing, 37-63% by soaking, and 6-80% by washing and cooking. Infants are highly vulnerable to As exposure; thus, these methods can be helpful for the production of rice-based infant foods. Although concern arises during the use of these methods that apart from decreasing the level of As in rice grain, they also lead to a significant loss of nutrients, such as macro- and micro-elements present in rice. Among these discussed methods, parboiling curtails 5-59%, polishing curtails 6-96%, soaking curtails 33-83%, and washing and cooking in different r/w reduce 8-81% of essential nutrients resulting in 2-90% reduction in contribution to the RDI of these nutrients through rice-based diet. Thus, these post-harvest arsenic removal methods, although reduce arsenic induced health hazard,but mayalso lead to malnutrition and compromised health in the population based on rice diet. There is a need to explore another way to reduce As from rice without compromising the nutrient availability or to supplement these nutrients through grain enrichment or by introducing additional dietary sources by changing eating habits; however, this may impose an extra economic burden on people.

Soil enzyme activities responded differently to short-term litter input manipulation under coniferous and broad-leaved forests in the subalpine area of Southwest China

Litter plays an irreplaceable role in terrestrial ecosystem carbon (C), nitrogen (N) and phosphorus (P) cycling, and its decomposition is largely regulated by litter quality, soil properties and enzyme activities. However, how soil enzyme activities respond to change in litter input under different forest types remains unsolved. Here, we investigated soil enzyme activities involved in C (β-glucosidase, BG), N (N-acetyl-β-glucosaminidase, NAG; leucine aminopeptidase, LAP) and P (acid phosphatase, ACP) under short-term litter manipulations (i.e. Detritus Input and Removal Treatment-DIRT: control, CK; double litter, DL; no roots and double litter, NRDL; no litter, NL; no roots, NR; no roots and no litter, NRNL) and associated influencing drivers in a coniferous forest (Pinus yunnanensis) and a broad-leaved forest (Quercus pannosa) in the subalpine area of Southwest China. Our results showed that litter removal treatment significantly reduced enzyme activities under two forest soils, with the stronger effect of the NR treatment on decreased enzyme activities compared to the NL treatment, possibly because roots could provide more available C sources and nutrient to microorganism and also immediately interact with soil minerals. In contrast, the short-term litter addition did not significantly affect enzyme activities under both two forest soils. Additionally, the BG activities in coniferous forest soil were characterized by a lower effect size compared to those in broad-leaved forest soil under the litter removal (NL and NRNL) treatments, but the higher effect size of LAP and ACP activities were observed under the NRNL treatment in the coniferous forest soil. This finding was attributed to higher organic C sources in the coniferous forest soil which could promote other nutrients utilization by microorganisms, leading to more N and P enzyme productions. We observed that the enzyme activities in the coniferous forest soil were closely related to soil N, P contents and microbial traits (i.e., fungal and bacterial structure), while enzyme activities in the broad-leaved forest soil primarily depended on microclimates (soil temperature and moisture) and soil properties (pH, dissolved organic C and P contents) under short-term litter manipulations. Overall, our results revealed the different pattern and the regulatory mechanism of soil enzyme activities under litter input manipulation of two forests, thereby advancing understanding of soil enzyme dynamics in association with initial litter quality and soil properties under future global change.

Key soil properties and their relationships with crop yields as affected by soil–landscape rehabilitation

AbstractTillage and water erosion induce spatially dependent changes in soil properties that influence productivity. Soil–landscape rehabilitation (returning translocated topsoil to landscape positions of soil loss by erosion) is one method to improve the productivity of severely eroded land. The objective of this study was to investigate relationships among key soil chemical, biological, and physical factors and crop growth and grain yield in eroded and rehabilitated landform positions. Soil–landscape rehabilitation was performed by moving 15–20 cm of topsoil from the lower slope to the upper slope positions of replicate plots; adjacent plots were left in their eroded condition. Crop response was monitored for 6 years. Rehabilitation resulted in large changes in the upper slope, especially in the most eroded landscape positions, where rehabilitated plots had lower inorganic carbon (IC) and higher organic carbon, available macronutrients, water infiltration rates, fungal and bacterial populations, and other measures of soil quality compared with control plots. Differences in surface soil IC that result from extensive erosion exposing calcareous subsoils, explained 70% of the yield variability in the upper slope. In the lower slope, the soil removal treatment was the main predictor of crop yield. Areas of soil removal had relatively high early‐season water content and low fungal and bacterial populations. Improving soil properties in areas of high soil loss by erosion increased both grain yield and yield stability across climatic conditions.

Zinc oxide – mesoporous silica nanocomposite: preparation, characterisation and application in water treatment for lead, cadmium and chromium removal

ABSTRACT Applications of nanomaterials in water and wastewater treatment and in environmental clean-up operations depend on the adsorption capacity of the materials for contaminants such as potentially toxic elements (PTEs). However, on their own nanoparticles can lose effectiveness as contaminant sorbents because of flocculation and aggregation. Embedding nanoparticles within a silica matrix offers one potential solution to the problem; hence, in this study, zinc oxide nanoparticles (ZnO-NP) were embedded in a mesoporous silica (MCM-41) matrix to create a composite material with potential for contaminants removal from water. The composite material (ZnO-mSiO2) and original ZnO-NP were characterised via UV-Vis, FTIR, XRD, TGA/DTA, BET, and SEM techniques, and were then evaluated for their capacities to remove cadmium (Cd), chromium (Cr) and lead (Pb) from water samples across varying conditions (pH, initial contaminant concentration, contact time and adsorbent mass: solution volume ratios). Langmuir and Freundlich adsorption isotherms were fit to the data to describe the adsorption observed. The ZnO-mSiO2 composite material proved highly effective at removing the PTEs (particularly Pb) across a wide range of conditions, with optimum removal rates achieved at pH 7 and above and 90 minutes contact time.

Effects of cholesterol removal treatment on the flavor and physicochemical properties of hot gel egg yolk

The aim of this study was to investigate effects of cholesterol removal treatment (CRT) on the flavor, taste, texture, color, and nutritional value of hot gel egg yolk (EY). The off-odor, volatile components and taste of EY treated with CRT were studied by electronic nose (E-nose), gas chromatography-mass spectrometry (GC–MS) and electronic tongue (E-tongue). The effect of CRT on the nutritional value of EY was studied by amino acid and fatty acid analysis. The CRT significantly reduced the content of hexanal, 2-amyl-furan, 1-octene-3-ol, styrene and heptanal in EY1-EY4, also decreased its bitter taste without affecting other taste and elasticity. In addition, the CRT did not affect the essential amino acids (EAA) content and L*, a* and b* values of EY1-EY4, but it led to the reduction in polyunsaturated fatty acids (PUFA) content. In general, the CRT is an effective way to reduce the off-odor of EY without affecting consumer acceptance.

Assessment of Biological Treatment for Ammonia Removal from Water Resources, Egypt

Egypt is depending entirely on the Nile water. The Rosetta branch of the river Nile serves as a vital freshwater source for domestic, agricultural, industrial, fisheries, and recreational purposes in several western Delta governorates of Egypt, with a daily flow averaging 21,500,000 m3/day. The branch faces significant challenges due to escalating ammonia concentrations stemming from agricultural drains along the river, industrial effluents from industrial activities, and fish farming cages. One particular issue arises during low-demand periods when the flow in the Rosetta branch diminishes. Annually, Egyptian authorities close water flows in a series of channels to facilitate maintenance, resulting in reduced water levels. This winter closure has impacted Kafr El Sheikh and El Beheira, located in northern Egypt, as the drainage of industrial wastes during this period has led to a high pollution load of ammonia and other pollutants. The elevated ammonium content has hindered coagulation, encouraged algal growth, and impeded the chlorine breakpoint during water chlorination processes. Laboratory experiments were conducted to investigate the ability of blue-green algae species (Anabaena sp., Scyndesmos sp., Chlorella sp.) and bacteria (Lactobacillus sp.) to uptake ammonia. This study revealed that single algal species achieved a maximum removal percentage of 30% for ammonia concentrations ranging from 5 to 7.5 mg/l, and mixed algal species attained removal percentages between 6% and 12% at constant retention times of 15 to 60 minutes. For single algal species, retention times exceeding 1 hour (2 and 5 hours) resulted in removal percentages ranging from 85% to 100%. For mixed algal species, removal percentages between 9% and 20% were observed for various retention times ranging from 15 minutes to 1 hour. When comparing the use of algal species mixtures, removal percentages of up to 30-50% were achieved. Additionally, the study found that the application of bacterial species (Lactobacillus sp.) to raw water samples with an average ammonia concentration of 7.8 mg/l resulted in a maximum removal percentage of 100% when using a bacterial content of 100-200 ml per 1-liter raw water sample volume, with varied retention times up to 2 hours.

Response of soil phosphorus fractions to litter removal in subalpine coniferous forest

Litter plays a crucial role in phosphorus (P) cycling, and its role in forest ecosystems may vary with different treatments and forest types. In this study, we investigated soil P fraction responses to litter removal in different forest types and how forest conversion affects the acquisition pathway of bioavailable P through an in situ controlled litter experiment. The results showed that the soil P content increased with the conversion of primary to secondary forest, which may be mostly related to the differences in nutrients and species richness between the two forest types. In addition, the main source of bioavailable P in primary forests was active organic P, while mineral P was the main bioavailable P source in secondary forests. Moreover, the three-year litter removal treatment significantly decreased the primary forest soil P fraction content while significantly increasing the secondary forest bioavailable P content. The main driving factors of the soil P fraction are also different between the two forest types, with AP activity and SOC as the major factors in the primary forest and pH as the main factor in the secondary forest.

Retracted: Clinical Study of Mobile Application- (App-) Based Family-Centered Care (FCC) Model Combined with Comprehensive Iron Removal Treatment in Children with Severe Beta Thalassemia.

[This retracts the article DOI: 10.1155/2022/4658709.].

Responses of Plant Species Diversity and Biomass to Forest Management Practices after Pine Wilt Disease

Pine wilt disease (PWD), which is caused by the Bursaphelenchus xylophilus, is one of the most serious biological invasions in East Asia. Removal of infected pine trees is generally used to prevent the spread of PWD. However, how this strategy affects plant species diversity and ecosystem functions needs to be clarified. We compared alpha diversity, species composition, and biomass for all woody plant species, adults, saplings, and seedlings in infected Masson pine forests where removal of infected trees occurred (CTD) and where infected trees were retained (UTD), uninfected Masson pine forests (PMF), and evergreen broad-leaved forests (EBF). UTD had the highest alpha diversity of all species and saplings, and UTD and PMF had the lowest alpha diversity of seedlings. CTD and EBF had a similar composition of seedlings, and CTD and UTD had similar species composition of all plant species and saplings. UTD had the lowest biomass for all species and adults but had the highest saplings biomass. Soil properties were significantly related to plant biomass. The retention of infected trees likely maintained soil fertility which increased species alpha diversity and the biomass of saplings, and unchanged species composition compared to the removal of infected trees, indicating that the retention strategy could help to maintain ecosystem functions.

Treatment of androgenetic alopecia by exosomes secreted from hair papilla cells and the intervention effect of LTF.

Androgenetic alopecia (AGA) is the most common cause of chronic progressive hair loss in men, and AGA has a severe negative impact on the quality of life and physical and mental health of patients. Four female C57BL/6 mice were isolated from DP cells in culture (≤4 generations) after stimulation of DPC proliferation by herbal concentrations obtained by the CCK-8 method, and exosomes were isolated by differential centrifugation at low temperature. Testosterone propionate and topical hair removal treatments were used together to establish the C57BL/6 mouse AGA model, which was treated with LTF, 5% minoxidil, and LTF-DPC-EXO, respectively. ELISA was used to detect serum hormone levels, in vivo tracing was used to observe dynamic changes in exosomes, H&E staining showed changes in mouse hair follicle tissue, and (q) RT-PCR and WB were used to detect dorsal skin VEGF, AKT1, and CASP3 expression in dorsal skin tissues. Hair regeneration was significant in the LTF group, minoxidil group, and LTF-DPC-EXO group mice, and the hair growth was only seen in the local skin in the model group. The hormone T in all treatment groups was lower than that in the model group, and e2 was higher than that in the model group. (q) RT-PCR and western blot showed that VEGF and AKT1 expressions were upregulated and Caspase3 expression was downregulated in the skin sections of mice in the treatment groups. DPC-EXO obtained through LTF may activate AKT1 and VEGF in the PI3K/AKT signaling pathway to inhibit CASP3, thereby protecting DPC to restore the hair growth.

Evaluation of pruning therapies in apple trees with fire blight

Ten experiments were conducted to evaluate the efficacy of methods to therapeutically remove fire blight cankers from apple trees with different age, vigor, training system and rootstock combinations in Washington, Oregon, Pennsylvania and New York, United States. Removal methods included pruning at varying distances from visible symptoms, utilization of a sanitizing agent and the use of a stub cut to minimize cankers on structural wood. Fire blight removal resulted in reductions of rootstock blight and tree death. Removal treatments resulted in fewer additional cankers compared to the no-treatment control in most trial sites and years. The standard best management practice (BMP) for removing fire blight was branch removal at 30 cm below the proximal edge of visibly cankered tissue with sanitized loppers. This practice significantly reduced the number of new systemically-caused symptoms compared to the no-treatment control in seven of nine experiments with significant reductions in five experiments. Aggressive removal, defined as BMP but branches removed approximately 76 cm from the proximal edge of visibly cankered tissue, generally did not improve the standard practice. Elimination of cutting tool sanitation did not result in more cankers than the standard practice. Breaking off diseased branches by hand provided a rapid removal method, but it resulted in a greater number of cankers in the orchard at the end of the season. In one of five experiments cutting which left a 13 cm stub distal to structural wood significantly reduced the number of cankers on structural wood compared to flush cut or 4 cm stubs.

Pronator Quadratus Muscle Flap for Prevention of Flexor Tendon Rupture after Distal Radius Volar Plating.

Flexor tendon rupture is a serious but rare complication that can occur after volar plating of distal radius fractures. This study aims to introduce a novel surgical technique that uses a pronator quadratus (PQ) muscle flap transposition to protect the flexor tendons from rupture or irritation and evaluate its outcomes. A retrospective review was conducted on 204 patients with unstable distal radius fractures who underwent a standard volar flexor carpi radialis approach with extended release of the PQ muscle during exposure. A PQ muscle flap was harvested and transposed over the distal edge of the plate after open reduction and internal fixation of the distal radius. Postoperatively, patients were evaluated for flexor tendon irritation and rupture. Patients who had this injury before the use of the PQ flap were compared with the patients who received the PQ flap. Of the 204 patients, 119 received the PQ flap, and 85 did not. The mean follow-up time was 30.4 months. Among the patients who did not receive the PQ flap, five (5.9%) required plate removal or conservative treatment for tendon irritation or rupture. In contrast, only one patient (0.8%) who received the PQ flap required plate removal for flexor tendon irritation. The PQ muscle flap is a quick and effective surgical technique that reduces the risk of flexor tendon rupture or irritation during distal radius fracture fixation. The PQ muscle flap acts as a buffer between the plate and tendon and is more effective than not transposing the muscle.

Separation of manganese and nickel from tantalum capacitor leach liquor- A comparative study of D2EHPA and CYANEX272 as extractant

Tantalum capacitor is widely distributed in almost every electronic equipment due to its superior volumetric efficiency, which allows miniaturization of size of the gadgets- a prime demand of today’s technological driven society. These capacitors, after reaching the end-of-life stage, should be considered as a rich secondary resources for recovery of different valuable metals. In these work, we have developed a hydrometallurgical method for recovery of manganese and nickel from tantalum capacitors leach liquor. Firstly, the capacitors were subjected to preprocessing treatment for removal of outer mold housing containing epoxy resin with silica. After this, the metal-rich fraction was subjected to leaching using hydrochloric acid to selectively dissolve all the manganese and nickel into the solution. This leach liquor was then subjected to solvent extraction using D2EHPA and CYANEX272 to study the effectiveness of these carrier in separation of manganese from nickel and other minute metals. Both the carrier shows excellent selectivity for separation of manganese from other metallic elements. Extraction efficiency of manganese was 97% and 99% for D2EHPA and CYANEX272, respectively.

Application of Picosecond Laser in Dermatology

ABSTRACT Background: Lasers are one of the most important treatment modalities in dermatology. Lasers interact with chromophores through several mechanisms that depend on fluence and pulse durations. Early lasers worked by photothermal interaction with pulse durations of 1 microsecond to 1 second. A picosecond laser is developed to confine photothermal effects and produce photomechanical effects and plasma induction. Purpose: To understand the mechanism of action and application of picosecond lasers for dermatological disorders. Review: Non-fractional picosecond lasers work by photomechanical interaction. Photomechanical interaction happens when pulse duration is less than inertial confinement time, causing fractures of chromophores with lower energy, or “cold ablation”. Fractional picosecond lasers work by laser-induced optical breakdown (LIOB). In LIOB, accelerated seed electrons cause an electron avalanche that produce a collection of free electrons called plasma, which ablates tissues. LIOB in the skin is always followed by photodisruption. In LIOB, vacuoles and debris were eliminated transdermally and dermal collagen and elastin increased. Picosecond laser may be applied in disorders requiring destruction of chromophores and for collagen and elastin disorders. It is currently the first-line treatment for tattoo removal (Nevus of Ota and Acquired Bilateral Nevus of Ota-like macules, or ABNOM). It has good efficacy and safety for solar lentigines, freckles, and cafe-au-lait macules (CALM). It is an additional treatment for moderate to severe melasma and hypertrophic scars, in combination with other treatments. The fractional picosecond laser showed moderate improvement and low risk of postinflammatory hyperpigmentation (PIH) for atrophic acne scars and produced improvement in striae alba.

Biosynthesis of zinc oxide nanoparticles mediated by Strobilanthes hamiltoniana: Characterizations, and its biological applications

Nanoparticles of Zinc oxide (ZnONPs), has a variety of applications such as antibacterial property, water treatment for pollutant removal, and as catalysts for organic reactions etc. and have been synthesized utilizing a variety of approaches, including green synthesis, chemical precipitation, sol–gel, hydrothermal synthesis, and microwave-assisted synthesis. In the present work, easy and economically viable ZnONPs were synthesized utilizing Strobilanthes hamiltoniana (SH) leaf extracts. Phytochemicals form S. hamiltoniana act as agents for reducing and capping the metal oxide ions. A range of analytical and microscopic techniques have been used to investigate the physical and chemical properties of ZnONPs. At 360 ​nm, green synthesized SH-ZnONPs showed robust UV–Vis absorption. The nanosize, shape, and crystalline structure of SH-ZnO NPs were characterized using XRD and electron microscopy techniques. Using SH-ZnO NPs, the photocatalytic activity of textile dyes such as Reactive blue 220 (RB-220), Reactive blue 222A (RB-222A), Reactive yellow 145 (RY-145) and Reactive yellow 86 (RY-86) dyes showed degradation efficiency of 97.3%, 78.57%, 88.88%, and 83.33% after 320 ​min. ZnONPs exhibited remarkable antibacterial effectiveness against bacterial and fungal pathogens using the Minimum inhibitory concentration approach. Their MIC values were calculated, and free radical scavenging experiments showed antioxidant activity. The SH-ZnONPs were validated using HepG2 (IC50) cancerous cells lines and showed promising anti-cancer activity. These results revealed that SH-ZnO NPs had promising benefits that could be utilized as a viable therapeutic candidate.

Fabrication of a novel bio-polymer adsorbent with high adsorptive capacity towards organic dyes

A novel adsorbent, CMC-T-CH, was fabricated by crosslinking of carboxymethyl cellulose (CMC) and chitosan (CH) with triethylenetetramine. The adsorbent's efficacy in removing the hazardous dyes, Direct blue (DB) and Congo red (CR), was investigated. Different physical, chemical, and biological methods have been employed to eliminate CR and DB dyes from aqueous solution, and adsorption has shown potential in eradicating these dyes effectively. Various characterization methods were employed to investigate the physicochemical characteristics of CMC-T-CH. The removal process was performed at optimized conditions of pH 6 for CR and pH 5 for DB at the temperature of 35 °C, resulting in maximum removal efficiencies of 99 % and 98.33 % for CR and DB, respectively. Langmuir isotherm and pseudo-second-order kinetic mathematical models were utilised to analysed the interaction of adsorbate and adsorbent during the removal process. The maximum theoretical adsorptive capacities of 519.53 and 534.25 mg/g were achieved for CR and DB removal, respectively. The regeneration study revealed that the dye-loaded CMC-T-CH could be reused several times. The phytotoxicity assay showed that the germination of Vigna mungo seeds improved after the removal treatment, thus confirming the potential of CMC-T-CH in the elimination of CR and DB.

Achieving advanced nitrogen removal and excess sludge treatment via single nitritation/anammox-fermentation combined system

The feasibility of treating wastewater and excess sludge via simultaneous nitritation, anammox, denitrification and fermentation (SNADF) was investigated in three parallel sequencing batch reactors (SBRs). SBR2 and SBR3 received exogenous nitrification–denitrification sludge and thermal hydrolysis sludge, respectively. Nitrogen removal efficiencies of 92.8 ± 5.9%, 94.6 ± 4.1%, 93.4 ± 4.8% were achieved in SBR1, SBR2, and SBR3, respectively (influent ammonium: 56.0–74.0 mg N/L), with low observed sludge yield of 0.02–0.15, −0.06–0.11, −0.17–0.05 kg mixed liquor suspended solids (MLSS)/kg chemical oxygen demand (COD). Anammox bacterial abundances increased from 3.6 × 109 ± 2.8 × 108 to 8.1 × 109 ± 2.3 × 108, 1.5 × 1010 ± 1.1 × 108, and 1.4 × 1010 ± 2.9 × 108 copies/L in SBR1-SBR3, respectively. The abundances of Nitrosomonas, genes (amo, hao) for partial nitrification, and narGHI genes (nitrate → nitrite) in dominant partial denitrifying bacteria (Candidatus Competibacter) were higher in SBR2 and SBR3 than that in SBR1. These results suggested that adding excess sludge promoted sludge reduction, nitrite production and anammox bacterial enrichment. The SNADF system could treat excess sludge, meanwhile, achieve advanced nitrogen removal.