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Sustainable and highly proton conductive nanopapers were prepared from carboxycellulose nanofibers and applied in PEM fuel cells.

Thallium(I) (Tl(I)) pollution has become a pressing environmental issue due to its harmful effect on human health and aquatic life. Effective technology to remove Tl(I) ions from drinking water can offer immediate societal benefits especially in the developing countries. In this study, a bio-adsorbent system based on nitro-oxidized nanocellulose (NOCNF) extracted from sorghum stalks was shown to be a highly effective Tl(I) removal medium. The nitro-oxidation process (NOP) is an energy-efficient, zero-waste approach that can extract nanocellulose from any lignocellulosic feedstock, where the effluent can be neutralized directly into a fertilizer without the need for post-treatment. The demonstrated NOCNF adsorbent exhibited high Tl(I) removal efficiency (>90% at concentration < 500 ppm) and high maximum removal capacity (Qm = 1898 mg/g using the Langmuir model). The Tl(I) adsorption mechanism by NOCNF was investigated by thorough characterization of NOCNF-Tl floc samples using spectroscopic (FTIR), diffraction (WAXD), microscopic (SEM, TEM, and AFM) and zeta-potential techniques. The results indicate that adsorption occurs mainly due to electrostatic attraction between cationic Tl(I) ions and anionic carboxylate groups on NOCNF, where the adsorbed Tl(I) sites become nuclei for the growth of thallium oxide nanocrystals at high Tl(I) concentrations. The mineralization process enhances the Tl(I) removal efficiency, and the mechanism is consistent with the isotherm data analysis using the Freundlich model.

Mercury contamination in drinking water is a worldwide problem due to its severely harming effects on the human body. A nanostructured natural bioadsorbent, carboxycellulose nanofiber extracted from raw moringa plant using the nitro-oxidation method (termed NOCNF), capable of effectively remediating this problem has been demonstrated. Nitro-oxidation is a simple approach that can extract carboxylated nanocellulose directly from raw biomass. In this study, the produced NOCNF contained a large density of carboxylate groups on the cellulose surface (0.97 mmol/g), capable of removing Hg2+ ions by simultaneous electrostatic-interactions and mineralization processes. Using the Langmuir analysis, the adsorption results indicated that the highest Hg2+ removal capacity of this NOCNF was 257.07 mg/g, which is higher than most of the reported values. The interactions between Hg2+ and NOCNF were further characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), transmission electron microscopy (TEM) with electron diffraction and wide-angle X-ray diffraction (WAXD) methods, suggesting the existence of two distinct removal mechanisms: predominant adsorption at low Hg2+concentrations (< 250 ppm) and predominant mineralization at high Hg2+ concentrations (> 1000 ppm). The applications of NOCNF were illustrated in both suspension form, as an adsorbent/coagulant, and dry powder form using filtration column. The results indicated that NOCNF in suspension exhibited a higher maximum removal efficiency of 81.6 % as compared to the dry state of 74.3 %. This work demonstrated the feasibility of extracting nanostructured adsorbents from biomass feedstocks to tackle the Hg2+ contamination problem in drinking water.

Nanocelluloses (NC) are nature-based sustainable biomaterials, which not only possess cellulosic properties but also have the important hallmarks of nanomaterials, such as large surface area, versatile reactive sites or functionalities, and scaffolding stability to host inorganic nanoparticles. This class of nanomaterials offers new opportunities for a broad spectrum of applications for clean water production that were once thought impractical. This Review covers substantial discussions based on evaluative judgments of the recent literature and technical advancements in the fields of coagulation/flocculation, adsorption, photocatalysis, and membrane filtration for water decontamination through proper understanding of fundamental knowledge of NC, such as purity, crystallinity, surface chemistry and charge, suspension rheology, morphology, mechanical properties, and film stability. To supplement these, discussions on low-cost and scalable NC extraction, new characterizations including solution small-angle X-ray scattering evaluation, and structure-property relationships of NC are also reviewed. Identifying knowledge gaps and drawing perspectives could generate guidance to overcome uncertainties associated with the adaptation of NC-enabled water purification technologies. Furthermore, the topics of simultaneous removal of multipollutants disposal and proper handling of post/spent NC are discussed. We believe NC-enabled remediation nanomaterials can be integrated into a broad range of water treatments, greatly improving the cost-effectiveness and sustainability of water purification.

Rice husks are an agricultural residue of great annual production and have a high cellulose content. In this study, we have prepared highly charged carboxyl cellulose nanofibers (CNFs) from rice husks using the TEMPO-oxidation method and the extracted CNFs were evaluated as an adsorbent for the removal of lead(II) and lanthanum(III) (Pb(II) and La(III)) ions from contaminated water. Three different forms of nanocellulose adsorbents were prepared: suspension, freeze-dried, and nanocomposite containing magnetic nanoparticles, where their adsorption performance was tested against the removal of the two chosen heavy metal ions. The maximum adsorption capacity of rice husk based CNFs was found to be the highest in the nanocellulose suspension, i.e., 193.2 mg g−1 for Pb(II) and 100.7 mg g−1 for La(III). The separation of the used adsorbent in the suspension was further facilitated by the gelation of the CNFs and metal cations, where the resulting floc could be removed by gravity-driven filtration. The absorption mechanism of the investigated CNF system is mainly due to electrostatic interactions between negatively charged carboxylate groups and multivalent metal ions. It was found that 90% lanthanum content in the form of lanthanum oxychloride (determined by X-ray powder diffraction) could be obtained by incinerating the CNF/LaCl3 gel. This study demonstrates a viable and sustainable solution to upcycle agricultural residues into remediation nanomaterials for the removal and recovery of toxic heavy metal ions from contaminated water.

Arsenite (As(III)) contamination in drinking water has become a worldwide problem in recent years, which leads to development of various As(III) remediation approaches. In this study, two biomass-based nanostructured materials, microscale dialdehyde cellulose–cysteine (MDAC–cys) and nanoscale dialdehyde cellulose–cysteine (NDAC–cys) fibers, have been prepared from wood pulp. Their As(III) removal efficiencies and mechanism were determined by combined adsorption, atomic fluorescence spectrometry, microscopy (scanning electron microscopy, transmission electron microscopy, and atomic force microscopy), and spectroscopy (Fourier transform infrared, 13C CPMAS NMR) methods. The adsorption results of these materials could be well described by the Freundlich isotherm model, where the maximum adsorption capacities estimated by the Langmuir isotherm model were 344.82 mg/g for MDAC–cys and 357.14 mg/g for NDAC–cys, respectively. Both MDAC–cys and NDAC–cys materials were further characterized by X-ray diffraction and thermogravimetric analysis, where the results indicated that the thiol groups (the S content in MDAC–cys was 12.70 and NDAC–cys was 17.15%) on cysteine were primarily responsible for the adsorption process. The nanostructured MDAC–cys system appeared to be more suitable for practical applications because of its high cost-effectiveness.

In this study, granulated activated charcoal (GAC) and bio charcoal (BC) is used as a filler in P3 biosand bag filter to study their filtration performance against a range of fluoride impurities from 1–1400 mg/L. A set of experiments are done to analyze the filtration efficiency of the sandbag filter against fluoride impurities after incorporating different amounts (e.g., 0.2, 2 kg) and a combination of GAC and BC. A combination of filler GAC and BC (1 kg each) have exhibited excellent results with 100% fluoride removal efficiency against 5 mg/L fluoride impurities for an entire experimental time of 165 min. It is because of the synergetic effect of adsorption caused by the high surface area (739 m2/g) of GAC and hydroxyapatite groups in BC. The data from remediation experiments using individual GAC and BC are fitted into the Langmuir and Freundlich Isotherm Models to check their adsorption mechanism and determine GAC and BC’s maximum adsorption capacity (Qm). The remediation data for both GAC and BC have shown the better fitting to the Langmuir Isotherm Model with a high R2 value of 0.994 and 0.970, respectively, showing the excellent conformity with monolayer adsorption. While the GAC and BC have presented negative Kf values of −1.08 and −0.72, respectively, for Freundlich Model, showing the non-conformity to multilayer adsorption. The Qm values obtained from Langmuir Model for GAC is 6.23 mg/g, and for BC, it is 9.13 mg/g. The pH study on adsorption efficiency of individual GAC and BC against 5 mg/L of fluoride impurities indicates the decrease in removal efficiency with an increase in pH from 3 to 9. For example, BC has shown removal efficiency of 99.8% at pH 3 and 99.5% at pH 9, while GAC has exhibited removal efficiency of 96.1% at pH 3 and 95.9% at pH 9. Importantly, this study presents the significance of the synergetic application of GAC and BC in the filters, where GAC and BC are different in their origin, functionalities, and surface characteristics.

Carboxycellulose nanofibers (CNFs) promise to be a sustainable and inexpensive alternative material for polymer electrolyte membranes compared to the expensive commercial Nafion membrane. However, its practical applications have been limited by its relatively low performance and reduced mechanical properties under typical operating conditions. In this study, carboxycellulose nanofibers were derived from wood pulp by TEMPO oxidation of the hydroxyl group present on the C6 position of the cellulose chain. Then, citric acid cross-linked CNF membranes were prepared by a solvent casting method to enhance performance. Results from FT-IR spectroscopy, 13C NMR spectroscopy, and XRD reveal a chemical cross-link between the citric acid and CNF, and the optimal fuel cell performance was obtained by cross-linking 70 mL of 0.20 wt % CNF suspension with 300 µL of 1.0 M citric acid solution. The membrane electrode assemblies (MEAs), operated in an oxygen atmosphere, exhibited the maximum power density of 27.7 mW cm−2 and the maximum current density of 111.8 mA cm−2 at 80 °C and 100% relative humidity (RH) for the citric acid cross-linked CNF membrane with 0.1 mg cm−2 Pt loading on the anode and cathode, which is approximately 30 times and 22 times better, respectively, than the uncross-linked CNF film. A minimum activation energy of 0.27 eV is achieved with the best-performing citric acid cross-linked CNF membrane, and a proton conductivity of 9.4 mS cm−1 is obtained at 80 °C. The surface morphology of carboxycellulose nanofibers and corresponding membranes were characterized by FIB/SEM, SEM/EDX, TEM, and AFM techniques. The effect of citric acid on the mechanical properties of the membrane was assessed by tensile strength DMA.

Raw wood was subjected to sequential oxidation to produce 2,3,6-tricarboxycellulose (TCC) nanofibers with a high surficial charge of 1.14 mmol/g in the form of carboxylate groups. Three oxidation steps, including nitro-oxidation, periodate, and sodium chlorite oxidation, were successfully applied to generate TCC nanofibers from raw wood. The morphology of extracted TCC nanofibers measured using TEM and AFM indicated the average length, width, and thickness were in the range of 750 ± 110, 4.5 ± 1.8, and 1.23 nm, respectively. Due to high negative surficial charges on TCC, it was studied for its absorption capabilities against Pb2+ ions. The remediation results indicated that a low concentration of TCC nanofibers (0.02 wt%) was able to remove a wide range of Pb2+ ion impurities from 5–250 ppm with an efficiency between 709–99%, whereby the maximum adsorption capacity (Qm) was 1569 mg/g with R2 0.69531 calculated from Langmuir fitting. It was observed that the high adsorption capacity of TCC nanofibers was due to the collective effect of adsorption and precipitation confirmed by the FTIR and SEM/EDS analysis. The high carboxylate content and fiber morphology of TCC has enabled it as an excellent substrate to remove Pb2+ ions impurities.

Understanding the morphology and flow behavior of cellulose nanofibers (CNFs) dispersed in organic solvents can improve the process of fabricating new cellulose-based nanocomposites. In this study,...

Two different chemical methods, TEMPO-oxidation and nitro-oxidation, were used to extract carboxyl cellulose nanofibers (CNFs) from non-wood biomass sources (i.e., jute, soft and hard spinifex grasses). The combined TEMPO-oxidation and homogenization approach was very efficient to produce CNFs from the cellulose component of biomass; however, the nitro-oxidation method was also found to be effective to extract CNFs directly from raw biomass even without mechanical treatment. The effect of these two methods on the resulting cross-section dimensions of CNFs was investigated by solution small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and atomic force microscopy (AFM). The UV-Vis spectroscopic data from 0.1 wt% TEMPO-oxidized nanofiber (TOCNF) and nitro-oxidized nanofiber (NOCNF) suspensions showed that TOCNF had the highest transparency (> 95%) because of better dispersion, resulted from the highest carboxylate content (1.2 mmol/g). The consistent scattering and microscopic results indicated that TOCNFs from jute and spinifex grasses possessed rectangular cross-sections, while NOCNFs exhibited near square cross-sections. This study revealed that different oxidation methods can result in different degrees of biomass exfoliation and different CNF morphology.

Regenerated microfibrillated cellulose (R-MFC) fibers were prepared successfully by a combined dissolution and regeneration approach using phosphoric acid/ethanol treatment on jute cellulose. The prepared R-MFC fibers possessed high surface area (10.74 m2/g), good aspect ratio (L/D = 30), and excellent thermal stability (Tmax = 352 °C). In addition, the fibers exhibited 3.84 wt % of phosphate groups (PO42–) with a ζ-potential of −8.4 mV and low crystallinity index (CI) of 47.5%. These R-MFC fibers were in the cellulose II polymorph, confirmed by 13C CPMAS NMR and WAXD measurements, and they were effective to anchor the growth of ZnO nanocrystals. WAXD and TEM examinations on the imbedded ZnO nanocrystals indicated that they possessed the hexagonal wurtzite crystal structure and could assemble into a flower-like morphology in the R-MFC scaffold. A R-MFC composite containing 41 wt % of ZnO nanocrystals was found to be very efficient to remove arsenic (As(V)) ions from water with the maximum capacity of 4,42...

Aloe vera, a short-stemmed shrub is described as a “wonder plant”, due to its vast uses in various medical products. Since many decades, extensive research has revealed that the pharmacological active ingredients are distributed in both the gel and rind of the Aloe vera leaves. A. vera is very popular in cosmetic and pharmaceutical industries and it is needed in large quantities with higher fractions of important constituents. To satisfy the market demand, intervention of microbial community seems to be a promising approach, which helps to increase the growth and metabolites along with plant fitness. Piriformospora indica is a root colonizing endophytic fungus, having unique plant growth-promoting properties. It helps the plant to acquire more nutrients from soil even under extreme physical and nutrient stress conditions. It interacts with a wide range of hosts. Interaction of P. indica with A. vera resulted in overall increase in plant biomass and greater shoot and root length, as well as number of shoots and roots as compared to control under both in vitro and in vivo environment conditions. Apart from that, the photosynthetic pigments (Chl a, Chl b and total Chl) and aloin content were observed significantly higher in A. vera plantlets colonized with symbiotic endophyte. The antioxidant activities were also tested and found significantly higher as compared to control plants. This imparts the potential of P. indica, to resist the plants against phyto-pathogenic microbes. P. indica has been proved as a potential candidate to enhance the biomass production along with various value additions in the form of active ingredients in A. vera.

Green and sustainable cellulose nanocrystals-TiO2 nanocomposite was prepared for environmental applications using a facile method comprised of thermal degradation of aqueous titanium precursors., Nanocellulose, which can be derived from any cellulosic biomass, has emerged as an appealing nanoscale scaffold to develop inorganic–organic nanocomposites for a wide range of applications. In this study, titanium dioxide (TiO2) nanocrystals were synthesized in the cellulose nanocrystal (CNC) scaffold using a simple approach, i.e., hydrolysis of a titanium oxysulfate precursor in a CNC suspension at low temperature. The resulting TiO2 nanoparticles exhibited a narrow size range between 3 and 5 nm, uniformly distributed on and strongly adhered to the CNC surface. The structure of the resulting nanocomposite was evaluated by transmission electron microscopy (TEM) and X-ray diffraction (XRD) methods. The growth mechanism of TiO2 nanocrystals in the CNC scaffold was also investigated by solution small-angle X-ray scattering (SAXS), where the results suggested the mineralization process could be described by the Lifshitz–Slyozov–Wagner theory for Ostwald ripening. The demonstrated TiO2/CNC nanocomposite system exhibited excellent performance in dye degradation and antibacterial activity, suitable for a wide range of environmental remediation applications.

Proton exchange membranes (PEMs), such as Nafion, are still one of the reasons for the high cost of PEMFCs. Among the alternatives, cellulose, a low cost and biodegradable material, has been considered in the form of its derivatives, such as cellulose acetate, bacterial cellulose or nanocellulose, as the PEM in fuel cells. However, its use involves more chemical synthesis steps. Here, we use low-cost 1.5-micron cellulose filter paper as the scaffold and prepare membranes for PEMFCs by simply impregnating it with a 10% Nafion solution or immersing it in resorcinol bis(diphenyl phosphate) (RDP). The prepared membranes are primarily composed of cellulose, with a cellulose to Nafion or RDP ratio of 2 : 1 or 1 : 1. The membrane electrode assemblies (MEAs) incorporating the as-prepared membranes exhibit a maximum output power of 23 mW cm−2 at 80 °C for the cellulose/Nafion membrane or 10 mW cm−2 at 60 °C for the cellulose/RDP membrane with only 0.1 mg cm−2 Pt loading on the anode and cathode, when operated in air. The stability results of the membranes after 100 hours of continuous operation indicate a loss of only 10% in power for the cellulose/Nafion membrane and 20% for the cellulose/RDP membrane. It is revealed by FTIR spectroscopy that both the Nafion polymer and RDP were hydrogen bonded to the cellulose fibers, facilitating proton conduction and stabilizing them against further dissolution.

The objective of this paper is to establish the significance of the mycoremediation of contaminants such as Cd2+ to achieve sustainable and eco-friendly remediation methods. Industries such as electroplating, paint, leather tanning, etc. release an enormous amount of Cd2+ in wastewater, which can drastically affect our flora and fauna. Herein, we report on the in vitro bioadsorption of Cd2+ ions using fungal isolates obtained from different contaminated industrial sites. The detailed studies revealed that two fungal species, i.e., Trichoderma fasciculatum and Trichoderma longibrachiatum, were found to be most effective against the removal of Cd2+ when screened for Cd2+ tolerance on potato dextrose agar (PDA) in different concentrations. Detailed adsorption studies were conducted by exploring various experimental factors such as incubation time, temperature, pH, inoculum size, and Cd2+ salt concentrations. Based on optimum experimental conditions, T. fasciculatum exhibited approximately 67.10% removal, while T. longibrachiatum shows 76.25% removal of Cd2+ ions at pH 5.0, 120 h incubation time, at 30&deg, C. The inoculum sizes for T. fasciculatum and T. longibrachiatum were 2.5% and 2.0%, respectively. Finally, the morphological changes due to Cd2+ accumulation were examined using scanning electron microscopy (SEM). Further, Fourier transform infrared spectroscopy (FTIR) spectroscopy reveals the presence of various functional groups (-CH, &ndash, C=O, NH and &ndash, OH), which seem to be responsible for the efficient binding of Cd2+ ions over the fungal surfaces.

Synthetic rubber produced from nonrenewable fossil fuel requires high energy costs and is dependent on the presumed unstable petroleum price. Natural rubber latex (NRL) is one of the major alternative sustainable rubber sources since it is derived from the plant &lsquo, Hevea brasiliensis&rsquo, Our study focuses on integrating sustainably processed carboxycellulose nanofibers from untreated jute biomass into NRL to enhance the mechanical strength of the material for various applications. The carboxycellulose nanofibers (NOCNF) having carboxyl content of 0.94 mmol/g was prepared and integrated into its nonionic form (&ndash, COONa) for its higher dispersion in water to increase the interfacial interaction between NRL and NOCNF. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) analyses of NOCNF showed the average dimensions of nanofibers were length (L) = 524 &plusmn, 203 nm, diameter (D) 7 &plusmn, 2 nm and thickness 2.9 nm. Furthermore, fourier transform infra-red spectrometry (FTIR) analysis of NOCNF depicted the presence of carboxyl group. However, the dynamic light scattering (DLS) measurement of NRL demonstrated an effective diameter in the range of 643 nm with polydispersity of 0.005. Tensile mechanical strengths were tested to observe the enhancement effects at various concentrations of NOCNF in the NRL. Mechanical properties of NRL/NOCNF films were determined by tensile testing, where the results showed an increasing trend of enhancement. With the increasing NOCNF concentration, the film modulus was found to increase quite substantially, but the elongation-to-break ratio decreased drastically. The presence of NOCNF changed the NRL film from elastic to brittle. However, at the NOCNF overlap concentration (0.2 wt. %), the film modulus seemed to be the highest.

High aspect ratio carboxycellulose nanofibers (NOCNF), having typical length over 1000 nm, width ∼4.6 nm, thickness ∼1.3 nm, and carboxylate content of 0.42 mmol/g, were extracted from jute fibers using a modified nitro-oxidation method. The extracted nanofiber was found to possess crystallinity of 69% (measured by wide-angle X-ray diffraction, WAXD), relatively higher than that of raw jute fibers (crystallinity ∼61%). Gelation of NOCNF in aqueous suspensions was observed due to the high aspect ratio of the fiber even at a relatively low concentration. Rheological studies on the NOCNF suspensions at different concentrations (0.01–1 wt %) revealed the shear-thinning behavior with increasing shear rate. The corresponding viscoelastic moduli (G′ and G′′) results indicated that the NOCNF suspension at concentration between 0.1 and 0.2 wt % possessed a liquid–gel transition. The rheological data near the gelation point could be fitted by the Winter–Chambon model, where the results confirmed the formation of a ...

Mechanistic behavior and flow properties of cellulose nanofibers (CNFs) in aqueous systems can be described by the crowding factor and the concept of contact points, which are functions of the aspect ratio and concentration of CNF in the suspension. In this study, CNFs with a range of aspect ratio and surface charge density (380–1360 μmol/g) were used to demonstrate this methodology. It was shown that the critical networking point of the CNF suspension, determined by rheological measurements, was consistent with the gel crowding factor, which was 16. Correlated to the crowding factor, both viscosity and modulus of the systems were found to decrease by increasing the charge density of CNF, which also affected the flocculation behavior. Interestingly, an anomalous rheological behavior was observed near the overlap concentration (0.05 wt %) of CNF, at which the crowding factor was below the gel crowding factor, and the storage modulus (G′) decreased dramatically at a given frequency threshold. This behavior ...

Carboxycellulose nanofibers were extracted from untreated jute using a simple nitro-oxidation method based on nitric acid/sodium nitrite. The characteristics of nitro-oxidized carboxycellulose nanofibers (NOCNF) with low crystallinity (35%), high carboxylate content (1.15 mmol/g) and high surface charge (− 70 mV) made them an excellent substrate for Pb(II) ion removal from water. For example, a low concentration of NOCNF suspension (0.23 wt%) could remove a wide range of Pb(II) ions ranging from 50 to 5000 ppm in a short time-interval ( 1000 ppm). Evidence of nanoscale lead hydroxide crystallization, induced by the lead(II)-NOCNF aggregated scaffold, was confirmed by FTIR, UV–visible spectroscopy, SEM/EDS, WAXD and TEM measurements.

Nanocelluloses, in the form of carboxycellulose nanofibers, with low crystallinity (CI ∼ 50%), high surface charge (−68 mV), and hydrophilicity (static contact angle 38°), were prepared from an untreated (raw) Australian spinifex grass using a nitro-oxidation method employing nitric acid and sodium nitrite. The resulting nanofibers (NOCNF) were found to be an effective medium to remove Cd2+ ions (cadmium(II)) from water. For example, a low concentration of NOCNF suspension (0.20 wt %) could remove Cd2+ ions over a large concentration range (50–5000 ppm) in a relatively short time period (≤5 min). The results showed that at low Cd2+ concentrations (below 500 ppm), the remediation mechanism was dominated by interactions between carboxylate groups on the NOCNF surface and Cd2+ ions, which also acted as a cross-linking agent to gel the NOCNF suspension. At high Cd2+ concentrations (above 1000 ppm), the remediation mechanism was dominated by the mineralization process of forming Cd(OH)2 nanocrystals, which was...

Carboxycellulose nanofibers (NOCNF) were extracted from untreated jute fibers using a simple nitro-oxidation method, employing nitric acid and sodium nitrite. The resulting NOCNF possessed high surface charge (−70 mV) and large carboxylate content (1.15 mmol/g), allowing them to be used as an effective medium to remove UO22+ ions from water. The UO22+ (or U(VI)) removal mechanism was found to include two stages: the initial stage of ionic adsorption on the NOCNF surface following by the later stage of uranyl hydroxide mineralization, as evidenced by the Fourier transform infrared, scanning electron microscopy with energy dispersive spectroscopy capabilities, transmission electron miscroscopy, and wide-angle X-ray diffraction results. Using the Langmuir isotherm model, the extracted NOCNF exhibited a very high maximum adsorption capacity (1470 mg/g), about several times higher than the most efficient adsorbent reported (poly(acrylic acid) hydrogel). It was also found that the remediation of UO22+ ions by N...

Carboxylated cellulose nanofibers (CNFs), having an average width of 7 nm and thickness of 1.5 nm, were produced by TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation method. The fiber cross-sectional dimensions were determined using small-angle X-ray scattering (SAXS), transmission electron microscopy and atomic force microscopy techniques, where the rheological properties under different concentration and ionic strength were also investigated. The formation of hydrogel was evidenced by increasing the CNF concentration or ionic strength of the solvent (water), while the gel structure in ion-induced CNF hydrogels was found to be relatively inhomogeneous. The gelation behavior was closely related to the segmental aggregation of charged CNF, which could be quantitatively characterized by the correlation length (ξ) from the low-angle scattering profile and the scattering invariant (Q) in SAXS.

One step green synthesis of silver nanoparticles (AgNPs) from silver nitrate (AgNO3) using Leucaena leucocephala seeds extract as the reducing agent at room temperature was performed. The bioreduced NPs were characterized by UV-vis spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) coupled with energy dispersive spectrophotometry, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) techniques. Qualitative information of major components in the seed extract was obtained through its phytochemical screening. The phytochemical data of L. leucocephala revealed the presence of terpenes, flavonoids, coumarins and sterols. The reaction was optimized for AgNO3, extract concentration and time duration for the reaction. The obtained NPs showed a characteristic UV peak of AgNPs at 420 nm. TEM and SEM images showed the spherical shaped NPs over which the extract coating was very prominent. The binding of L. leucocephala seeds extract onto NPs was tested using FTIR and TGA. The antifungal activity of the as-synthesized NPs against two fungal species, namely Phlebiopsis gigantea and Echinodontium taxodii, was studied. The antimicrobial effect of the as-synthesized NPs was ascertained against Escherichia coli and Staphylococcus aureus. The antioxidant potential of the AgNPs was tested with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging. Also, the sensitivity of the NPs towards Fe3+ ions was tested in aqueous media.

In this paper, we report the simple synthesis, detailed characterization, and total wastewater cleanup by adsorption using bare and surfactant-functionalized cerium oxide (CeO2) nanoparticles. The synthesis of CeO2 nanoparticles was performed by a facile aqueous solution process and characterized by a diverse range of techniques, which confirmed that the nanoparticles are well-crystalline, possessing good structural and optical properties. The competence of the prepared nanoparticles was further explored to determine the dye removal efficiency. The developed nanoparticles have also provided chlorine-free disinfection of water. The observed results revealed that the synthesized nanoparticles efficiently lower the pollutant concentrations, reduced turbidity, and exhibited significant reductions in total dissolved solids, chemical and biochemical oxygen demands, and pathogenic load. Interestingly, the surfactant-functionalized nanoparticles revealed that they possess the ability to remove approximately 99% o...

Proton-exchange membrane fuel cells (PEMFCs) are considered to be one of the most promising clean technologies to mitigate climate change, air pollution, and energy crisis. Although PEMFCs have been intensively investigated over the past five decades, the relatively low current density, high cost, and poor durability remain as obstacles to full commercialization. In this study, we present the development and the application of a porosity-tunable carbon aerogel (CA) as an alternative to the carbon support in the PEMFC to overcome its technical barriers. CA demonstrates highly tunable mesopore volume and surface area. The N2 isotherm with non-localized density functional theory analysis shows the optimized CA had extremely high mesopore volume, which was 4.26 times larger than the traditional carbon support (i.e., Vulcan XC-72R). Transmission electron microscopy shows a better catalyst (i.e., platinum nanoparticles) distribution on the CA support. This even distribution of platinum nanoparticles significantly enhances the catalyst utilization of the electrodes in our cyclic voltammetry analysis. It also contributes up to a 713% higher specific power density in our fuel cell testing. The standard accelerated stress tests exhibit that CA has excellent durability compared with the conventional carbon support. Thus, the mesoporous CA provides an efficient and durable alternative to existing carbon material as a catalyst support in PEMFCs.

Background: In developing and resource-limited countries alternative screening methods like VIA, VILI, and Pap smear are used in detection of premalignant and malignant lesions of cervix. The aim of our study was to compare the efficacies of VIA, VILI, and Pap smear in detection of premalignant and malignant lesions of cervix.Methods: The study was conducted for a period of one year in the department of obstetrics and gynaecology, Dr. Rajendra Prasad Government Medical College, Kangra at Tanda, Himachal Pradesh. Women who attended the outdoor patient department of obstetrics and gynecology were subjected to collection of Pap Smear, VIA followed by VILI and a thorough pelvic examination.Results: Among the 350 women studied, 59 women (16.9%) had abnormal VIA, 64 women (18.2%) had abnormal VILI. On pap smear, 10 women were reported as ASCUS, 11 as L-SIL and 1 as H-SIL. Cervical biopsy was done in 98 women, out of which 70 had one or more abnormality on VIA, VILI, or Pap, and 28 women who had normal results. Sixteen women (16.3%) reported as CIN-1 and 2 women (2.07%) as CIN-3. VIA and VILI had a higher sensitivity as compared to pap. However, pap was more specific. The PPV of pap was also much higher as compared to VIA and VILI, whereas there was no difference in NPV of the three.Conclusions: Authors observed that VIA presented the best sensitivity (88.8%), followed by VILI (83.3%), and Pap (72.2%). Pap smear had the highest specificity of 97.2%. The positive predictive value of Pap was higher as compared to VIA and VILI, whereas there was no difference in NPV of the three. VIA and VILI have good sensitivity, with reasonable specificity and because of their cost effectiveness and ease of availability, these can be an alternative screening modality for cervical cancer screening.

Membrane technology remains the most energy-efficient process for removing contaminants (micrometer-size particles to angstrom-size hydrated ions) from water. However, the current membrane technolo ...

A simple approach was developed to prepare carboxycellulose nanofibers directly from untreated biomass using nitric acid or nitric acid-sodium nitrite mixtures. Experiments indicated that this approach greatly reduced the need for multichemicals, and offered significant benefits in lowering the consumption of water and electric energy, when compared with conventional multiple-step processes at bench scale (e.g., TEMPO oxidation). Additionally, the effluent produced by this approach could be efficaciously neutralized using base to produce nitrogen-rich salts as fertilizers. TEM measurements of resulting nanofibers from different biomasses, possessed dimensions in the range of 190–370 and 4–5 nm, having PDI = 0.29–0.38. These nanofibers exhibited lower crystallinity than untreated jute fibers as determined by TEM diffraction, WAXD and 13C CPMAS NMR (e.g., WAXD crystallinity index was ∼35% for nanofibers vs 62% for jute). Nanofibers with low crystallinity were found to be effective for removal of heavy metal...

Poly(lactic acid) (PLA) foams, with the combination of shish-kebab and spherulite nanoporous structure in skin and core layer respectively, was prepared using a novel technique comprising loop oscillating push–pull molding (LOPPM) and supercritical carbon dioxide low-temperature foaming process (SC−CO2LTFP). The foams present superior impact toughness which is 6-fold higher than that of neat PLA, and no significant decrease was observed for the storage modulus. Moreover, SC−CO2LTFP at soaking temperature ranging from 110 to 150 °C were performed to determine the evolution of pore morphology. The ultratough and supermoduli are unprecedented for PLA, and are in great need for broader applications.

Agricultural residues derived cellulose was used to synthesize a new series of carboxy functionalized cellulosic nanoparticles (quasi-spherical shaped, 13.2–21.5% carboxyl content) and macro-sized 6-carboxycelluloses (long-fibril shaped, 1.7–22% carboxyl content). The DP (50–70) and yield (upto 46%) of nanoparticles were manipulated by controlling the reaction temperature and time. TGA/DTG thermographs of the carboxycelluloses gave thermostability data and co-related well with the residual crystalline, amorphous, and anhydroglucuronic acid content. The particle shape and size had no effect on the thermal stability. Some derivatives were fully or partially soluble in aqueous alkali and non-aqueous solvents, which can lead to increased versatility of these polymers.

Background: Abnormal uterine bleeding(AUB) is a common clinical presentation in gynecology. Alteration in thyroid hormones level has been associated with menstrual disturbances. This study is aimed to know the prevalence of thyroid disorders amongst AUB patients and also the different patterns of menstrual abnormalities associated with thyroid disorders.Methods: 100 Patient of clinically diagnosed AUB were taken from gynecology OPD. All the patients from 19 to 45 age groups presenting with menstrual disturbances were tested for thyroid function by measuring ST3, ST4, and S.TSH.Results: Out of 100 women of AUB, majority were in the age group of 31-40 years (38%), 54% were multiparous and 44% presented with menorrhagia. 65% were euthyroid, 17% had subclinical hypothyroidism, 15% had overt hypothyroidism and 3% were diagnosed as hyperthyroid. Subclinical hypothyroidism, overt hypothyroidism and hyperthyroidism were detected mostly in the age group of 31-40 years. The commonest bleeding abnormalities in hypothyroid patient were menorrhagia and polymenorrhoea. While most of the hyperthyroid cases were oligomenorrhoic.Conclusions: The study concludes that biochemical evaluation of thyroid function is an easy, reliable method and should be made mandatory in all cases of AUB.

Oxidized celluloses have been used for decades as antimicrobial wound gauzes and surgical cotton. We now report the successful synthesis of a next generation narrow size range (25-35nm) spherical shaped nanoparticles of 2,3,6-tricarboxycellulose based on cellulose I structural features, for applications as new antimicrobial materials. This study adds to our previous study of 6-carboxycellulose. A wide range of bacteria such as Escherichia coli, Staphloccocus aureus, Bacillus subtilis and Mycobacterium tuberculosis (non-pathogenic as well as pathogenic strains) were affected by these polymers in in vitro studies. Activity against Mycobacteria were noted at high concentrations (MIC99 values 250-1000μg/ml, as compared to anti-TB drug Isoniazid 0.3μg/ml). However, the broad spectrum activity of oxidized celluloses and their nanoparticles against a wide range of bacteria, including Mycobacteria, show that these materials are promising new biocompatible and biodegradable drug delivery vehicles wherein they can play the dual role of being a drug encapsulant as well as a broad spectrum anti-microbial and anti-TB drug.

Background: This study was carried out to find the colposcopic findings in the symptomatic patients with cervical erosion and correlate the findings with cytology and histopathology.Methods: All the patients coming to gynaecological OPD with symptoms of white discharge, pruritus vulvae, menstrual irregularities were examined by per speculum examination and all those who had cervical erosion were included in the study and pap smear and colposcopy both were done in all subjects. The colposcopic guided biopsy was done in women with abnormal findings on colposcopy (50 women) and reports were compared. Abnormal colposcopic findings were graded according to Reid’s colposcopic index (RCI).Results: Majority of patients came with the complaint of white discharge per vaginum (55%).Out of 120 patients, 85 women (70.9%) had inflammatory pap smear and 35 women (29.1%)had abnormal pap smear. All patients underwent colposcopic examination and out of 120 patients, 67(55.8%) showed normal colposcopic findings and 50 women (41.6%) had abnormal colposcopic finding and biopsy was taken. 3 women had unsatisfactory colposcopy. Histopathology confirmed 24 (48%) women with CIN I and 12 (24%) CIN II and 6 (12%) CIN III and 2 (4%) women with carcinoma cervix. The colposcopy findings and histopathology correlated in 88%.Conclusions: Colposcopy should be prescribed to all symptomatic patients with cervical erosion as it is a good diagnostic tool for pre-malignant conditions of cervix and correlates well with histopathological findings.

Background: The objective of the study was to review the impact of thyroid status on the fertility and to study the prevalence of hyperprolactinaemia in infertility.Methods: A total of 150 subjects were divided into 3 groups: 50 primary infertility, 50 secondary infertility and 50 controls. The incidence of hyperprolactinaemia and thyroid disorders was studied in all the three groups.Results: The incidence of hyperprolactinaemia was 41% in all infertile subjects (60% with primary and 22% in secondary infertility) and 6% in controls. The incidence of hypothyroidism was 17% in infertility (18% in primary and 16% in secondary infertility) and 8% in controls.Conclusions: In this study there is a positive correlation between increased prolactin levels and hypothyroidism and such patients’ exhibit ovulatory failure. All patients with infertility should undergo prolactin levels and thyroid profile.

Oxidized cellulose containing carboxyl and aldehyde functional groups represent an important class of cellulose derivatives. In this study effect of incrementally increasing COOH and CHO groups at C2, C3, and C6 positions of cellulose and nanocellulose has been investigated, with a view to understanding their effect on thermal treatment of cellulose. The results show that 2,3-dialdehyde cellulose (DAC) is the most thermally stable oxidized product of cellulose while the most unstable derivatives contain carboxyl group at the C6 position (6CC). Carboxymethylcellulose (CMC), with carboxymethyl group on C6 position, is more stable than 6CC. Multi-functionalized celluloses 2,3,6-tricarboxycellulose and 6-carboxy-2,3-dialdehyde, have the same level of thermal stability as 6CC, showing that the presence of carboxyl at the C6 is a key destabilizing factor in the thermal stability of oxidized cellulose products. More the number of reducing end groups on the polymer chain, lower the thermal stability of the cellulose, as proved by comparing the TGA/DTG of monomeric analogs dextrose, cellobiose and glucuronic acid with the oxidized celluloses. The thermal stability trend observed for oxidized celluloses was DAC>DCC>nanoparticles>dextrose>glucuronic acid, caused by extent of reducing ends and COOH groups.

Cellulose-I swells considerably in phosphoric acid, and converts to amorphous cellulose via a cellulose-II transition state. Controlled oxidation of cellulose-I to 6-carboxycellulose (6 CC) using HNO3-H3PO4-NaNO2 oxidation system led to the selective production of 6 CC's of varying carboxyl contents (1.7-22%) as well as various shapes and sizes (macro-sized fibrils of several micron length and/or spherical nanoparticles of 25-35 nm), depending on the reaction conditions. 6 CC's having less than 14% carboxyl content were largely in cellulose-II form (WAXRD values in-between cellulose I and cellulose II), whereas at 14-22% the 6 CC's were largely amorphous; only trace crystallinity was observed at 19% and 22% carboxyl 6 CC. Spherical nanoparticles retained a high degree of crystallinity having cellulose-I structure, whereas the macro-sized fibrils were largely converted to cellulose-II structure. Analysis by WAXRD as well as by CP-MAS (13)C NMR studies gave similar conclusions. Reduced molecular weight with progressive oxidation, including presence of oligomers, was also evident from an increase in the reducing-end carbon peak at ∼ 92 ppm. For high oxidation levels (>14%) the NMR 92-96 ppm peaks disappeared on extracting with dilute alkali, due to soluble oligomers being removed.

Information technology played an important role in information and knowledge dissemination in the last decade in the almost all the domains through the development of internet, wireless, satellites and mobile based intelligent knowledge based information system. These systems need timely expert advice to make them more productive and competitive. By implementing them as knowledge servers, it becomes economically feasible, profitable, and beneficial to users to share knowledge. The Indian tariff structure for power generation utilities has also undergone major revision under the ABT regime. As a result, the operation philosophy employed by power generation utilities also has undergone change under the ABT. The proposed solution aims to help the end user (as a large power generation utility) to manage their resources in the most optimal and economic fashion under the new regime. Scheduling implies drawing up a generation program to cater to forecast power demand at a minimum cost subject to transmission system constraints, capability of generating units & other factors (e.g. voltage profile, system security & system sustainability under grid disturbance). Architecture for Optimization of Generator Scheduling under ABT Regime Using Intelligent Agents is proposed involving Tariff modeling engine, Generation scheduling engine, Generation target achievement engine, etc.

Marketing plays an important role to increase the institutional sales. It provides the awareness to business customers about their products and services and explains the benefits of using their products and services so that they can deliver the best to their customers. For example a hotel chain that sources its raw material from a quality raw material supplier ensures that it will deliver good food and services to end user. Business to business selling is expanding its footprint across all the industries. There are very limited researches available which explains how marketing strategy impacts the institutional selling. With this view, this research has been conducted to understand how marketing strategy impacts the institutional sales. In order to provide a clear focus, the research covers banking industries both private and public banks. This research is also based on the Impact of marketing strategies on Institutional sales in Indore District.

Nutritional value of pulses is a widely accepted but the presence of antinutritional factors in its composition imposes a restriction in its consumption. Different processing treatments (germination, boiling, pressure cooking and roasting) were employed for reduction of various antinutritional factors (Phytic acid, polyphenols, tannins, saponins, oxalates and trypsin inhibitor activity) in chickpea. Among various treatments employed pressure cooking resulted in maximum reduction of all types of antinutritional factors. Maximum reduction was observed in tannins (93.97%) and polyphenols (87.71%). Processing treatments showed significant effect on protein fraction, fatty acid profile and mineral content of chickpea. The albumins were least affected on processing. Germination increased the linolenic acid to 48.42 percent. Fe and K resulted in increase of 56.89 and 28.6 percent respectively.

Salivary gland tumours are rare and the most confusing tumours, which comprise