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1.
Environ Monit Assess ; 196(1): 97, 2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38153601

RESUMEN

Monitoring heavy metals (HMs) across source distance and depth distribution near coal mining sites is essential for preventing environmental pollution and health risks. This study investigated the distribution of selected HMs, cadmium (Cd2+), chromium (Cr2+), copper (Cu2+), manganese (Mn2+), nickel (Ni2+), lead (Pb2+), and zinc (Zn2+), in soil samples collected from ten sites (S-1-S-10) at two different depths (0-15 and 15-30 cm) and distances of 50, 100, and 200 m from a mining source. Additionally, three plant species, Prosopis spp., Justicia spp., and wheat, were collected to assess HM bioavailability and leaf accumulation. Coal mine activities' impact on soil properties and their HM associations were also explored. Results reveal HM concentrations except for Cr2+ exceeding World Health Organization (WHO) limits. In surface soil, Cd2+ (58%), Cu2+ (93%), Mn2+ (68%), Ni2+ (80%), Pb2+ (35%), and Zn2+ (88%) surpassed permissible limits. Subsurface soil also exhibited elevated Cd2+ (53%), Cu2+ (83%), Mn2+ (60%), Ni2+ (80%), Pb2+ (35%), and Zn2+ (77%). Plant species displayed varying HM levels, exceeding permissible limits, with average concentrations of 1.4, 1.34, 1.42, 4.1, 2.74, 2.0, and 1.98 mg kg-1 for Cd2+, Pb2+, Cr2+, Cu2+, Mn2+, Ni2+, and Zn2+, respectively. Bioaccumulation factors were highest in wheat, Prosopis spp., and Justicia spp. Source distance and depth distribution significantly influenced soil pH, electrical conductivity (EC), and soil organic carbon (SOC). Soil pH and EC increased with an increase in soil depth, while SOC decreased. Pearson correlation analysis revealed varying relationships between soil properties and HMs, showing a considerably negative correlation. Concentrations of HMs decreased with increasing depth and distance from mining activities, validated by regression analysis. Findings suggest crops from these soils may pose health risks for consumption.


Asunto(s)
Minas de Carbón , Metales Pesados , Bioacumulación , Cadmio , Cobre , Carbono , Plomo , Suelo , Monitoreo del Ambiente , Contaminación Ambiental
2.
Environ Pollut ; 307: 119413, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35525515

RESUMEN

Current research reveals the positive role of iron oxide nanoparticles (IONPs) and selenium (Se) in extenuation of arsenic (As) induced toxicity in Cucumis melo. C. melo plants grown in As spiked soil (20 mg kg-1 As) showed reduced growth, chlorophyll (Chl) content, photosynthetic rate, stomatal conductivity and transpiration. On the other hand, the alone applications of IONPs or Se improved growth and physiochemical parameters of C. melo plants. Additionally, exogenous application IONPs and Se synergistically improved the activity of antioxidative enzymes and glyoxalase system in C. melo plants. In addition, the collective treatment of IONPs and Se reduced As uptake, enhanced rate of photosynthesis and increased gas exchange attributes of C. melo plants under As stress. Interactive effect of IONPs and Se regulated reduced glutathione (GSH), oxidized glutathione (GSSG) and ascorbate (AsA) content in C. melo plants exposed to As-contaminated Soil. IONPs and Se treatment also regulated expression of respiratory burst oxidase homologue D (RBOHD) gene, chlorophyll synthase (CHLG) and protochlorophyllide oxidoreductase (POR). Therefore, the combined treatment of IONPs and Se may enhance the growth of crop plants by alleviating As stress.


Asunto(s)
Arsénico , Cucumis melo , Selenio , Antioxidantes/metabolismo , Arsénico/toxicidad , Clorofila/metabolismo , Suplementos Dietéticos , Expresión Génica , Glutatión/metabolismo , Nanopartículas Magnéticas de Óxido de Hierro , Estrés Oxidativo , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Fotosíntesis , Protoclorofilida/farmacología , Selenio/farmacología , Suelo
3.
Environ Sci Pollut Res Int ; 29(8): 11359-11373, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34536224

RESUMEN

Pakistan is placed among the most vulnerable countries with relation to climate change and its impacts on agricultural productivity. Cotton is staged as the cash crop of the country and the main source of raw material for textile, oil, and feed industry. Varying environmental attributes have significant effects on the duration of vegetative and reproductive stages of cotton crop. To evaluate the potential impacts of varied temperatures regimes in different sowing times, field experiments were carried out throughout the cotton growing areas of Pakistan from Faisalabad in Central Punjab to RYK in Southern Punjab and Sakrand in Sindh to Dera Ismail Khan in Khyber Pakhtunkhwa (KPK) Province. Crop was sown on six different sowing dates starting from 1st March towards 15th May with 2-week intervals for two crop seasons (2016 and 2017). The timing of phenological events like emergence, squaring, flowering, and boll opening was recorded on calendar days and cumulative heat units (GDDs) were calculated for flowering and boll opening stages. Heat use efficiency for these sowing times was estimated. Data regarding yield-related parameters like opened bolls per plant, average boll weight, and seed cotton yield were also recorded during the study. Results revealed that duration of the growth stages was significantly affected by variation in mean thermal kinetics in varied sowing times in all four different environments. Seed cotton yield and heat use efficiency were also varied among the locations and sowing dates. The maximum seed cotton yield was recorded in Sakrand location at 15th April sowing date. The dependence of the phenological advancement on temperature and negative impacts of higher thermal stress on cotton productivity were also confirmed throughout the cotton growing zone of Pakistan.


Asunto(s)
Agricultura , Gossypium/crecimiento & desarrollo , Calor , Cambio Climático , Pakistán
4.
Sci Rep ; 11(1): 18416, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-34531439

RESUMEN

Soil with heavy metals contamination, mainly lead (Pb), cadmium (Cd), and chromium (Cr) is a progressively worldwide alarming environmental problem. Recently, biochar has been used as a soil amendment to remediate contaminated soils, but little work has been done to compare with other organic amendments like compost. We investigated biochar and compost's comparative effect on Pb, Cd, and Cr immobilization in soil, photosynthesis, and growth of maize plants. Ten kg soil was placed in pots and were spiked with Pb, Cd, and Cr at concentrations 20, 10, 20 mg kg-1. The biochar and compost treatments included 0, 0.5, 1, 2, and 4% were separately applied to the soil. The crop from pots was harvested after 60 days. The results show that the highest reduction of AB-DTPA extractable Pb, Cd, and Cr in soil was 79%, 61% and 78% with 4% biochar, followed by 61%, 43% and 60% with 4% compost compared to the control, respectively. Similarly, the highest reduction in shoot Pb, Cd, and Cr concentration was 71%, 63% and 78%with 4% biochar, followed by 50%, 50% and 71% with 4% compost than the control, respectively. The maximum increase in shoot and dry root weight, total chlorophyll contents, and gas exchange characteristics were recorded with 4% biochar, followed by 4% compost than the control. The maximum increase in soil organic matter and total nitrogen (N) was recorded at 4% biochar application while available phosphorus and potassium in the soil at 4% compost application. It is concluded that both biochar and compost decreased heavy metals availability in the soil, reducing toxicity in the plant. However, biochar was most effective in reducing heavy metals content in soil and plant compared to compost. In the future, more low-cost, eco-friendly soil remediation methods should be developed for better soil health and plant productivity.

5.
Adv Sci (Weinh) ; 8(22): e2102540, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34553500

RESUMEN

Emulsion templating is at the forefront of producing a wide array of porous materials that offers interconnected porous structure, easy permeability, homogeneous flow-through, high diffusion rates, convective mass transfer, and direct accessibility to interact with atoms/ions/molecules throughout the exterior and interior of the bulk. These interesting features together with easily available ingredients, facile preparation methods, flexible pore-size tuning protocols, controlled surface modification strategies, good physicochemical and dimensional stability, lightweight, convenient processing and subsequent recovery, superior pollutants remediation/monitoring performance, and decent recyclability underscore the benchmark potential of the emulsion-templated porous materials in large-scale practical environmental applications. To this end, many research breakthroughs in emulsion templating technique witnessed by the recent achievements have been widely unfolded and currently being extensively explored to address many of the environmental challenges. Taking into account the burgeoning progress of the emulsion-templated porous materials in the environmental field, this review article provides a conceptual overview of emulsions and emulsion templating technique, sums up the general procedures to design and fabricate many state-of-the-art emulsion-templated porous materials, and presents a critical overview of their marked momentum in adsorption, separation, disinfection, catalysis/degradation, capture, and sensing of the inorganic, organic and biological contaminants in water and air.

6.
Korean J Chem Eng ; 38(9): 1768-1780, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34226783

RESUMEN

Petroleum facilities containing welded steel bulk flammable liquid product storage tanks possess sundry fire hazards inherent to the facility. These installations urgently require indigenous efficient firefighting systems. So, the efficient design of firewater and firefighting foam system is dynamic in controlling fire-related emergencies. The paper deals with the in-depth conceptualization of the design and analysis of firefighting systems for a typical petroleum handling, processing and storage facility in compliance with international standards. The study is aimed to formulate the elementary technique for designing an optimized firefighting system. The proposed objective was achieved by considering an ideal tank farm site that is most commonly located in a range of terminal stations, pumping stations, petroleum refineries, well sites, etc. Sufficient illumination was enumerated on the standardized classification of the liquid fuel product with respect their flammability range. Special guidelines regarding firefighting system design basis were defined and an optimized firefighting and foam system design was developed. Moreover, sufficient limitations that must be considered during the firefighting of huge tank fires are discussed. This comprehensive numerical design philosophy offers a simple and wide-ranging guide to industrial practitioners by formulating the principles for industrial firefighting system design.

7.
ACS Appl Mater Interfaces ; 13(23): 27400-27410, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34081850

RESUMEN

Emulsion template-guided strategy has been used to produce porous architectures with exquisite structure, tailored morphology, and exclusive features for ubiquitous applications. Notwithstanding, the practical water remediation is often marred by their transport-limited behavior and fragility. To circumvent these conundrums, we prepared hierarchically porous poly(acrylic acid)-alumina nanocomposite beads by solidifying the droplets of emulsions jointly stabilized by the organic surfactants and alumina nanoparticles. By virtue of their positive charge, the alumina nanoparticles got entrapped within the poly(acrylic acid) scaffolds that excluded the risk of secondary contamination typically observed with conventional nanocomposites. Being amenable to surface modification, the carboxyl moieties of the beaded polymer were further exploited to covalently tether branched polyethylenimine throughout the exterior and interior surface of the porous matrix via a grafting-to approach. The macropores expedite an active fluid flow and easier adsorbate transport throughout the functionalized nanocomposites whose overall higher density of positive charge over a certain pH range electrostatically attracts and effectively adsorbs the negatively charged Cr(VI) complexes and anionic congo red ions/molecules from water. This proof-of-concept synthetic approach and postsynthetic modification offer an improved mechanical robustness to these macrosized multifunctional nanocomposite beads for their easier processing, thereby paving the way for the point-of-use water purification technology development.

8.
Langmuir ; 35(40): 13165-13173, 2019 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-31525878

RESUMEN

Emulsion templating has emerged as a cutting-edge technique to prepare a wide array of porous polymer-metal nanocomposites with intriguing properties. Using this strategy, we set out to prepare novel hierarchically porous poly(vinylsulfonic acid) beads, which were then used for the in situ production of silver nanoparticles to obtain poly(vinylsulfonic acid)-Ag nanocomposite beads via a facile approach. Owing to their multimodal macro-meso-/microporosity that accounts for their decent BET surface areas (170.75-197.74 m2/g) and easier mass diffusion and transport together with the synergistic benefits of very small silver nanoparticles (down to ∼3.77 nm), the nanocomposite beads are found effective to remove Hg(II) and RhB and to kill Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. The adsorption capacities (167.98-190.58 mg/g) of these materials for Hg(II) surpass some recently reported benchmark materials. The larger size (1.56 ± 0.20-1.50 ± 0.14 mm) of the beads that helps favor the handling and subsequent recovery for recycling is also very useful to further broaden the horizons of these materials to develop decentralized water treatment systems.

9.
Langmuir ; 35(27): 8996-9003, 2019 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-31189312

RESUMEN

Tainting of waterbodies with noxious industrial waste is the gravest environmental concern of the day that continues to wreak inevitable havoc on human health. To cleanup these hard-to-remove life-threatening water contaminants, we have prepared hierarchically porous poly(acrylic acid) beads by emulsion templating. These emulsion-templated macroporous polymer beads not only mediate the synthesis of Fe3O4 nanoparticles inside their porous network using a coprecipitation approach but, in turn, create diverse anchoring sites to immobilize an additional poly(acrylic acid) active layer onto the nanocomposite beads. These post-synthetically modified nanocomposite beads with macropores and abundant acrylic acid moieties offer the ready mass transfer and fair advantage of relatively higher overall negative charge to efficiently adsorb lead [Pb(II)] and crystal violet with impressive performance-even superior to many of the materials explored in this regard so far. Furthermore, the strong entanglement of nanoparticles in the porous polymeric scaffolds tackles the curb of trade-off between all-round effective remediation and secondary pollution and the millimeter size eases their processing and recovery during the adsorption tests, thereby making these materials practically worthwhile.

10.
Pak J Med Sci ; 34(1): 82-87, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29643884

RESUMEN

OBJECTIVES: Brachdactyly a genetic disorder associated with the abnormal development of metacarpals, phalanges or both which results in the shortening of hands and feet. Mutations in the contributing genes has been recognized with the majority of the investigated syndromic form of brachdactyly. The current study was proposed to examine mutation in NOG and GDF5 genes in a Pakistani family. METHODS: Poly Acrylamide Gel Electrophoresis and Polymerase Chain Reaction was used for the genomic screening and linkage analysis to observe the mutation in genes. The samples were collected from Luckki Marwat district, KPK, while the research study was conducted in the department of Biochemistry, Quaid-I-Azam University, Islamabad, Pakistan. RESULTS: After survey, family was identified with brachdactyly type A2 and investigated a heterozygous arginine to glutamine exchange in the growth demarcation factor 5 in all the victim persons. Different types of skeletal dysplasia resulted due to mutation in the GDF5 genes. Novel GDF5 genes mutations were reported with distinct limb malformation and sequencing of coding region revealed that the mildly affected individuals were heterozygous while the harshly affected individuals were homozygous. CONCLUSION: The current study reported the genetic variability and concluded that the Brachdacytyly type A2 and type B2 resulted due to mutation in GDF5 and NOG genes respectively. A new subtype of brachydactyly (BDB2) was instigated as a result of novel mutations in NOG. The mutation has been reported for the first time in Pakistani population and especially in Pushtoon ethnic population.

11.
RSC Adv ; 8(52): 29628-29636, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-35547285

RESUMEN

Nano/microscale TiO2 materials and their composites have reached the pinnacle of their photocatalytic performances to destroy persistent organic pollutants and waterborne microorganisms, but their practical applications are limited by the drawbacks associated with their stability, leaching, processing and separation. To overcome these shortcomings, we have prepared hierarchically porous nanostructured TiO2 macrobeads via an exotemplating or nanocasting strategy by infiltrating the TiO2 sol into the emulsion-templated porous polyacrylamide scaffold followed by its gelation, drying and calcination. The nanoscale TiO2 building units tailor the shape of the porous polymeric network after calcination thereby retaining the macroscale morphology of polymer beads after template removal. A novel combination of the hierarchical macroporosity, orderly crystalline anatase nature, nanoscale feature and good surface area revealed by the relevant characterization tools makes these TiO2 scaffolds particularly effective for superior degradation of methylene blue with the enhanced rate constant and efficient disinfection of E. coli and S. aureus under UV light. The macrosize and mechanical stability of these purely TiO2 beaded architectures have several potential advantages over conventional TiO2 nanocomposites and slurry systems to address the inherent bottlenecks of secondary contamination, difficult operation and energy-intensive post-recovery processes that are indeed deemed to be the barriers to develop practically useful water treatment technologies.

12.
ACS Appl Mater Interfaces ; 9(28): 24190-24197, 2017 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-28644011

RESUMEN

Water, the driver of nature, has always been polluted by the blind hurling of highly toxic contaminants, but human-friendly science has continuously been presenting better avenues to help solve these challenging issues. In this connection, the present study introduces novel nanocomposites composed of emulsion-templated hierarchically porous poly(1-vinylimidazole) beads loaded with the silver nanoparticles generated via an in situ approach. These nanocomposites have been thoroughly characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, Brunauer-Emmett-Teller, and field emission scanning electron microscopy. The appropriate surface chemistry, good thermal stability, swelling behavior, porosity, and nanodimensions contributed to achieve very good performance in water treatment. Owing to their easier handling and separation, these novel nanocomposites are highly efficient to remove arsenic and eriochrome black T with decent adsorption capacities in addition to the inactivation and killing of Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria.

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