Publications by authors named "Rajendra P. Singh"

Bioenergy generation from microalgae can significantly contribute to climate mitigation and renewable energy production. In this regard, several multi-criteria decision-making method were employed to prioritize appropriate microalgae culture system for bioenergy production. Entropy weight, Criteria Importance Through Intercriteria Correlation (CRITIC) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) were the employed MCDA method.

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Frequent algal blooms cause algal cells and their algal organic matter (AOM) to become critical precursors of disinfection by-products (DBPs) during water treatment. The presence of bromide ion (Br) in water has been demonstrated to affect the formation laws and species distribution of DBPs. However, few researchers have addressed the formation and toxicity alteration of halonitromethanes (HNMs) from algae during disinfection in the presence of Br.

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Cupric ions (Cu) are ubiquitous in surface waters and can influence disinfection byproducts (DBPs) formation in water disinfection processes. This work explored the effects of Cu on chlorinated DBPs (Cl-DBPs) formation from six representative nitrophenol compounds (NCs) during UV irradiation followed by a subsequent chlorination (i.e.

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Nitrophenol compounds (NCs) are widely distributed in water environments and regarded as important precursors of disinfection byproducts (DBPs). Herein, 4-nitrophenol and 2-amino-4-nitrophenol were selected as representative NCs to explore chlorinated DBPs (Cl-DBPs) formation during UV/post-chlorination. Dichloronitromethane (DCNM), trichloronitromethane (TCNM), dichloroacetonitrile (DCAN), and trichloromethane (TCM) were formed from 4-nitrophenol and 2-amino-4-nitrophenol during UV/post-chlorination, and the yields of individual Cl-DBPs from 2-amino-4-nitrophenol were higher than those from 4-nitrophenol.

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The impact of different operational parameters on the composting efficiency and compost quality during pilot-scale membrane-covered composting (MCC) of food waste (FW) was evaluated. Four factors were assessed in an orthogonal experiment at three different levels: initial mixture moisture (IMM, 55 %, 60 %, and 65 %), aeration time (AT, 6, 9, and 12 h/d), aeration rate (AR, 0.2, 0.

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Evaluation of the hydrological performance of grassed swales usually needs long-term monitoring data. At present, suitable techniques for simulating the hydrological performance using limited monitoring data are not available. Therefore, current study aims to investigate the relationship between saturated hydraulic conductivity (K) fitting results and rainfall characteristics of various events series length.

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This study attempted to determine the influence of diverse green wastes on food waste digestate composting and the improvement of operational conditions. Various effects of the green wastes (GW), with different types and sizes, initial substrate mixture C/N ratios, compost pile heights, and turning frequencies on the food waste digestate (FWD) composting were examined in the current work. The findings showed that the use of street sweeping green waste (SSGW) as an additive can maintain the thermophilic stage of the FWD composting for 28 days, while the end-product contained the greatest amounts of total phosphorus (TP, 2.

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The current study focused on analyzing the effect of different types of bulking agents and other factors on fed-batch composting and the structure of microbial communities. The results indicated that the introduction of bulking agents to fed-batch composting significantly improved composting efficiency as well as compost product quality. In particular, using green waste as a bulking agent, the compost products would achieve good performance in the following indicators: moisture (3.

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Brominated halonitromethanes (Br-HNMs) are generated in water disinfection processes and present high toxicity to human health. This work used aspartic acid (ASP) as the precursor to reveal that bromide (Br) induced the production of Br-HNMs in the UV/chlorine disinfection process. Consequently, six Br-HNMs were identified, and their yields presented an increasing and then declining evolution over the reaction time from 0 to 15 min.

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Saturated hydraulic conductivity (K) of the filler layer in grassed swales are varying in the changing environment. In most of the hydrological models, K is assumed as constant or decrease with a clogging factor. However, the K measured on site cannot be the input of the hydrological model directly.

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LED-UV/chlorine is a promising alternative disinfection technology that emits mono-wavelength light for high germicidal efficiency. Halonitromethanes (HNMs) are highly cytotoxic and genotoxic disinfection byproducts that can be formed during LED-UV/chlorine disinfection. Thus, this work aimed to investigate the HNMs formation from glycine (Gly) during LED-UV/chlorine disinfection.

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A high-quality substrate layer is the cornerstone of supporting that green roofs (GRs) can become an efficient and sustainable nature-based solution to urban environmental problems. In the present study, three lightweight substrate materials commonly used in GRs of peat soil, vermiculite and pumice with four appropriate proportions of the nutrient substrate and the mineral substrates were selected to install twelve substrate modules. The lightweight property, water-holding, nutrient retention and rainwater reduction performance of the substrate modules were investigated by the laboratory determination methods and the simulated rainfall experiment.

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Article Synopsis
  • The study looked at pollution in water from open wells, bore wells, and drinking water from river areas.
  • They tested how safe the water is for drinking and farming using special water quality indices.
  • The results showed that most places had good drinking water, but some areas had poor quality, especially in Karaipakkam.
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Bromide ion (Br) is known as a prevalent component in water environments, which exhibits significant impacts on halonitromethanes (HNMs) formation. This study was performed to explore and compare the formation, toxicity, and mechanisms of HNMs from poly(diallyl dimethyl ammonium chloride) (PDDACl) in the absence and presence of Br in the UV/monochloramine (UV/NHCl) disinfection process. The results showed that chlorinated HNMs were found in the absence of Br, while brominated (chlorinated) HNMs and brominated HNMs were found in the presence of Br.

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Chlorinated-halonitromethanes (Cl-HNMs) including chloronitromethane (CNM), dichloronitromethane (DCNM), and trichloronitromethane (TCNM) are nitrogenous disinfection by-products, which have high cytotoxicity and genotoxicity to human. This study aimed to investigate the degradation kinetic modeling and mechanism of Cl-HNMs under monochloramine activated by ultraviolet of 254 nm (UV/NHCl) treatment. The first-principle kinetic model of UV/NHCl process was developed to simulate Cl-HNMs degradation.

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UV/chlor(am)ine are efficient for achieving multiple-barrier disinfection and maintaining residuals, while bromide (Br) has notable impacts on the formation and toxicity of halonitromethanes (HNMs) during UV/chlor(am)ine disinfection. This study investigated the effects of Br on HNMs formation and toxicity alteration during UV/chlor(am)ine disinfection of nitrate containing humic acid (HA) water. Results reveal that the maximum concentration of HNMs during UV/chlorine disinfection was 12.

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Background: The World Health Organization (WHO) 2019 antiretroviral treatment guidelines recommend use of optimal treatment regimens in all populations. Dolutegravir-based regimens are the preferred first-line and second-line treatment in infants and children with HIV 4 weeks of age and above. There is an urgent need for optimal pediatric formulations of dolutegravir as single-entity (SE) and fixed-dose combination (FDC) to ensure correct dosing and adherence for swallowing and palatability.

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To evaluate the long-term performance of bioretention cell (BRC), a study was undertaken to assess the flow distribution and conductivity. Despite initial conductivity of the original medium being the common predictor of hydraulic performance, most of the BRCs are affected by conductivity variations during actual operation. This happen due to the fact that microbial behavior plays an important role in the conductivity variations.

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Halonitromethanes (HNMs) is a typical class of nitrogenous disinfection byproducts with high toxicity. The effect of Br on the formation and transformation of HNMs from dimethylamine (DMA) during the ultraviolet (UV)/chlorine disinfection has been investigated in current study. Results reveal that only chloronitromethane, dichloronitromethane and trichloronitromethane (TCNM) could be found during the UV/chlorine disinfection.

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Pharmacokinetics, safety, and tolerability of abacavir 600 mg/dolutegravir 50 mg/lamivudine 300 mg were assessed in this phase 1, single-arm, open-label, single-dose study in fasted healthy male (n = 4) and female (n = 8) participants of Japanese heritage. Participants received a single dose of abacavir 600 mg/dolutegravir 50 mg/lamivudine 300 mg after an 8-hour fast, with safety assessments and blood samples for pharmacokinetic parameters collected through 72 hours after dosing. Geometric mean maximum plasma concentrations were 5.

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Arbuscular mycorrhizal fungi (AMF) and its symbiosis with Canna indica on nitrogen (N) absorption was investigated for the remediation of contaminated soil. Canna indica plants with rhizome and leaf integrity intact were collected in spring and autumn seasons. To maintain the ideal nutrient composition, Hoagland concentrated nutrient solution was diluted with deionized water and additional nutrient solution was added periodically.

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Article Synopsis
  • LDPE passive sampling is an effective method for measuring chemical concentrations in various environments, with key focus on partitioning coefficients (K) between LDPE and matrices like water, air, and seawater.
  • Three datasets were developed involving the collection of 255, 117, and 190 compounds, and multiple prediction models (pp-LFER and QSPR) were created to estimate the partition coefficients with strong accuracy and reliability.
  • The models highlighted critical properties like molecular size and hydrophobicity as key factors influencing how chemicals partition between LDPE and environmental matrices, and they can be used to predict unknown K values, enhancing our understanding of organic contaminant distribution in the environment.
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The loss regularity of nitrogen (N), phosphorus (P), and chemical oxygen demand (COD) of runoff under different rainfall intensity and different management practices in Phyllostachys praecox cv. prevernalis forest land was studied. The total nitrogen (TN) and COD concentration in runoff were significantly correlated with the rainfall intensity under the three management modes named as control, fertilization, and cover.

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Article Synopsis
  • Scientists created a special system called a microbial fuel cell with a built wetland (CW-MFC) to help remove certain antibiotics from water.
  • This system was really good at getting rid of more than 90% of one antibiotic and also decreased methane gas, which can be bad for the environment.
  • They found out that adding a special material, manganese ore, helped reduce methane emissions even more, and some bacteria changed in the process, making the system work better.
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To evaluate the enhancing of the biological nitrogen removal effectiveness by electromagnetic wave loading on returned sludge in the A/A/O reactor, some experiments were completed with the returned sludge loaded by 2,450 MHz electromagnetic wave. The excess sludge yield and pollutant removal effect of the system were evaluated. Results showed that stronger denitrification effect and less sludge yield were achieved.

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