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Native starch has low adsorption ability due to lack of specific functional groups. To increase the adsorption efficiency of native starch, it needs to be chemically modified. The modification produces specific functional groups on the backbone of starch and increases its adsorption efficacy towards dyes and heavy metals. The modified starch-based adsorbents (succinylated starches, starch phosphate, starch-based composites and nanoparticles, starch-based hydrogels, cross-linked and carboxylated starches and so on) are more useful due to their large surface area, available polar sites and reproducibility in the degree of activation. In this review article we have discussed the application of modified starches as sorbents for the removal of dyes and heavy metals from wastewater. It further highlighted the optimized conditions used for the removal of heavy metals and dyes by the modified starches and the interactions generated between the adsorbent and adsorbate. This article presented the most recent literature and will spark new ideas for researchers working in this field.

Phenol is the toxicant present in cigarette smoke that causes pulmonary diseases, eyes infection, and even various kinds of cancer. So, in this research, an attempt was done to prepare a suitable absorbent to remove phenol from cigarette smoke. A novel bio-based adsorbent succinylated carboxymethyl starch (S-CMS) was prepared by reacting carboxymethyl starch (CMS) with succinic anhydride (SA) in the presenting of N, N-dimethylformamide (DMF) solvent and pyridine. The structure of the S-CMS was confirmed by spectroscopic techniques including proton nuclear magnetic resonance and Fourier transform infrared. The S-CMS crystallinity and thermal properties were checked by x-ray diffraction and thermogravimetric analysis. The results showed a decrease in thermal properties and crystallinity for S-CMS. The S-CMS were tested as adsorbents for the removal of phenol. The adsorption efficiencies of CMS, S-CMS1, S-CMS2, and S-CMS3 towards phenol were shown to be 0.297 g/g, 0.321 g/g, 0.322 g/g, and 0.324 g/g, respectively.

High molecular weight polyvinylpyrrolidone (PVP) and seeding conditions are considered to have important roles in the synthesis of AgNWs. In this work, we report a versatile synthesis of AgNWs in a salt-free environment and under Ar inert atmosphere using high molecular weight PVP and seeding step during the synthetic process. The high molecular weight PVP was found to efficiently promote the preparation of AgNWs via supporting the proper growth control of AgNWs on {111} facets and selective growth on {100} facets. The seeding step facilitates the formation of seeds such as multiple twinned nanoparticles (MTPs) and single crystal seeds, which promoted the feasible formation of AgNWs. The shape and size of the synthesized AgNWs were characterized by SEM and TEM. The crystalline nature of the synthesized AgNWs was characterized by HRTEM, SAED and XRD, and their LSPR peaks were confirmed by UV-Vis spectroscopy. The conductive properties of the synthesized AgNWs were determined by preparing their thin conductive film on a PET substrate. The prepared AgNWs thin films exhibited good sheet resistance.

Succinylated starches (SS) were prepared by the reaction of normal starch (NS) and porous starch (PS) with succinic anhydride (SA) in the presence of DMF solvent and base pyridine, respectively. The proton nuclear magnetic resonance and Fourier transform infrared were used to confirm the successful synthesis of the SS (SS1, SS2, SS3 and SS4, respectively). The X-ray diffractometer XPert PRO (Cu Kα, λ = 1.54 A) was used to study the crystallinity of NS, PS and SS. The XRD analysis showed that the SS exhibited amorphous nature after succinylation. Thermogravimetric analysis and differential thermal analysis of NS, PS and SS showed that succinylation decreased the thermal stability. The morphology of the NS, PS and SS was studied by SEM. These SS were used as adsorbents for phenol removal. The adsorption efficiencies for phenol by NS, SS1, SS2, SS3 and SS4 were found to be 0.084 g/g, 0.165 g/g, 0.173 g/g, 0.183 g/g and 0.189 g/g, respectively.

Cellulose nanocrystals (CNCs) is one of the outstanding nano-material. So far, much researcher nowadays has been developed their applications. It acquires several properties, particular in bio-degradability and low cost with chemical stability. These properties make CNCs a promising resource to replace fossil resources for the production of industrial materials, chemicals and biofuels. CNCs based materials have attracted much attention during the past few years and are widely used in biomedical materials, pharmaceutical industry, the auxiliary catalytic matrix and nanomedicine were discussed here. The CNCs industry is booming due to many possibilities of drug supply. Successful delivery is influenced by a number of factors, including the selection of suitable materials for research and development. It is used in the transdermal preparations to improve clinical results. It is used as an interdisciplinary approach that takes into accounts, opportunities and potential benefits of developing different management strategies in nature. It has attracted wide attention because of its unique nature, such as renewable, non-toxic, high surface area and the utilization of hydroxyl groups for its functionalization potential to develop various products and replace traditional petrochemical and non-biodegradable materials. This overview summarizes the latest development of model modeling for CNCs. Considerable progress has been made in handling these functions and potentially using of CNCs in different high-tech applications in different areas. This all are highlighted here.

The development of telecommunication instruments and electronic devices caused a number of subtle electromagnetic radiations, which have adverse effects on the equipment and especially the health of humans. To date, in order to reduce the harmful radiations, considerable attention has been given to the microwave absorbers due to their several attributes, such as cost-effectiveness, environmental stability and lightweight. Given that polyaniline possesses all above-mentioned properties, in this review, we mainly focus on preparation methods and application of polyaniline-based composites as microwave absorbers, including polyaniline/carbon material composites, polyaniline/magnetic material composites and polyaniline/carbon material/magnetic material composites, and the mechanisms of electromagnetic (EM) wave dissipation have also been discussed. The polyaniline-based composites are more efficient for microwave absorption due to their unique properties; therefore, they could be considered as good materials for microwave absorbers to hinder the EM radiations.

To overcome the migration problems of burning rate catalysts (BRCs), ferrocene-based amide compounds (AM-Fcs) were synthesized. The successful synthesis of AM-Fcs were confirmed by proton nuclear magnetic resonance, and Fourier transform infrared spectroscopy. The electrochemistry behaviors of AM-Fcs were examined by cyclic voltammetry (CV). The CV experimental results indicated that these AM-Fcs showed good electrochemical performances, which were contributable to their burning rate (BR) catalytic activity in composite solid propellants. The anti-migration test of AM-Fcs verified significantly slower migration than ferrocene and the most commonly used BRCs catocene. Thermal stability and BR catalytic impact of AM-Fcs on the thermal decomposition of ammonium perchlorate (AP) were studied by thermogravimetry and differential thermogravimetry. These AM-Fcs revealed good catalytic behaviors on the thermal degradation of AP.

Poly(methyl silsesquioxanes), PMSQ, are cyclic siloxanes with unusual features that are also widely known as silsesquioxanes due to their organic peripheral and inorganic silicate interior. These are organosilicon compounds with the chemical formula [RSiO3/2]n that are called silsesquioxanes where R may be alkyl, alkoxyl or aryl. These hybrid materials are quite famous to exhibit garner properties from their different inorganic and organic parts in a synergistic way. However, dealing with long-standing challenges and environmentally friendly requirements, we synthesized these PMSQ fine nanoparticles in our own laboratory. These nanoparticles were uniformly dispersed in a bio-based epoxy resin, and the mechanical properties, adhesive strength, and morphology of resultant nanocomposites were evaluated. PMSQ were found to be successfully dispersed into the bio-based epoxy resin in varying weight fractions of 1 wt%, 3 wt% and 5 wt%. The mechanical properties of PMSO-loaded epoxy resin samples are reported as functions of processing parameters. The highly dispersed PMSQ/bio-based epoxy resin nanocomposites showed high tensile modulus and strength values. In addition, it was found that fracture toughness values of all samples prepared by ultra-sonication were increased by increasing PMSQ content in nanocomposites. The corresponding synthesized epoxy resin composites were characterized by different techniques including, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). SEM analysis reported high uniformly dispersed spherical PMSQ particles in epoxy resin. The bonding properties including, tensile modulus and strength of PMSQ were determined using a general testing machine. The obtained results confirmed a significant improvement in bonding performance of PMSQ dispersed in bio-based epoxy resin. PMSQ attracts feasible widespread applications in mechanical and environmental engineering.

Cellulose nanocrystals (CNCs) received great attention in various fields, because of their high efficacy, high aspect ratio, low density, renewability and non-toxicity which make them ideal candidates. Here, various properties and applications especially, thermal, mechanical, adhesives, coatings etc., to introduce CNCs, a hydrophilic and colloidally stable, rigid rod-shaped bio-based nanomaterial with high strength and high surface area. CNCs enhance properties of different compounds under different conditions. The research in the last decade reveals that couple of years CNCs possesses high nature, than any other kind of compound, widely used in industrial and other products, as well as for human benefits. Over the past decade, CNCs is an abundant natural nanomaterial with great potential, has attracted many researches towards its use. Dispersing in polar solvent, they assemble to form multiphase or higher order structures yielding desirable optical and structural properties. The present review summarizes the recent achievements in the development of CNCs templating, highlights considerable progress has been achieved in addressing these multidimensional properties and potential use of CNCs in a wide range of high-tech applications in different fields.

Ferrocene-based polythiophene (PT) composites containing different carbon fillers like multi-walled carbon nanotubes (MWCNTs), reduced graphene oxide (RGO) and carbon black (CB) were prepared through in situ chemical oxidative polymerization method. The prepared PT composites were characterized by employing SEM, TEM, FTIR, XRD and XPS techniques. The thermal stability of the PT composites was investigated by TG analysis. It was found that the thermal stability of PT composites was highly improved as compared with pure PT. The electrical conductivity of the composites was measured by a typical four-probe method. Electrical conductivity measurements indicated that the PT composites showed excellent electrical conductivity. Electromagnetic interference shielding effectiveness (EMI SE) of the composites was measured by using coaxial method in the frequency range of 1–4.5 GHz. The total shielding effectiveness (SET) achieved for PT composites along with MWCNT, RGO and CB was − 24 dB, − 11.27 dB, and − 10.46 dB at 50 wt% composite sample loading in the paraffin wax matrix, respectively. Therefore, the PT-MWCNT composite can be used for the EMI shielding applications.

A theoretical study of a second-grade nanofluid over a porous medium has been conducted. Stagnation point flow is considered. Effects of nonlinear radiative heat flux, dissipation and Joule heating are considered in the modeling of energy equation. Furthermore, chemical reaction is accounted. The wall is not stationary, but stretching at rate a. Total irreversibility rate is obtained through the second thermodynamics law. Slip mechanism of nanoparticles like Brownian movement and thermophoresis are considered. Suitable transformations lead to ordinary system. Solution development is done through HAM. Effects of pertinent variables are graphically discussed. Skin friction and temperature gradient are examined graphically versus different parameters. It is observed that velocity field decreased versus larger magnetic parameter. Temperature enhances versus rising values of magnetic and radiation variables. Main idea of present flow is listed.

We have studied the advances made in chemical modification of cellulose nanocrystals (CNCs) and their corresponding applications. Different synthetic methods such as esterification and etherification, cross-linking and grafting techniques parameters, etc., are used in CNCs formation. As CNCs are well studied for their renewable purposes like oxidation, grafting, copolymerization reaction, etc. Their biodegradability is of great advantage as it can easily be modified with other related functional groups giving high stiffness, strength, low density and long life to metals and other materials. Cellulose polymer is mostly used due to its neutrality and its wide applications in furniture, packaging, textile, food medical products, etc. Mankind has found a great deal of benefit from cellulose owing to its many applications over a period of hundreds of years. This review presents a detailed account of pronounced effect of CNCs, revealed during their numerous applications and their potential use in wide ranging fields. The recent research reveals multidimensional properties and great advancements of CNCs made at an industrial level. CNCs also exhibit high efficiency in all application areas, described in detail here.

Synthetic dyes are commonly utilized in various industries like food stuff, synthetic plastics, textile, paper, plastic, leather, and cosmetic industries. Some part of these dyes are drained back in to the environment, where these dyes cause different diseases like cancer, irritation to skin, respiratory tract and eyes. So removal of dyes from water is the need of time. Here, three different starch-g-polymethyl methacrylates (S-g-PMMAs) were synthesized by treating starch with different amount of methyl methacrylate in the presence of KPS as initiator in green solvent water. The prepared modified starches were characterized by Proton Nuclear Magnetic Resonance and Infrared spectroscopic Technique which confirmed that synthesis of starch-g-polymethyl methacrylates occured successful. TGA and DTG analysis were carried out to find out the thermal properties of the modified samples. Crystallinity of starch and starch-g-polymethyl methacrylates was determined through XRD analysis which confirmed that crystalline nature of starch was lost after modification. The modified starch with the highest grafting ratio was then applied for the adsorption of Rhodamine 6G form water using various parameters. It was found tremendous adsorbent for Rhodamine 6G.

In this article, starch phosphate-g-poly (methacrylic acids) (SP-g-PMAAs) were synthesized by dual modification. Firstly starch phosphate (SP) was synthesized by phosphorylation of native starch (NS) with mono sodium-phosphate and di sodium-phosphate. Afterwards, methacrylic acid (MAA) was grafted onto SP via free radical polymerization to synthesize SP-g-PMAAs. The structure of the SP and SP-g-PMAAs was investigated by phosphorus nuclear magnetic resonance, proton nuclear magnetic resonance and fourier-transform infrared spectroscopy. The X-ray diffraction studies showed that the modification diminished the crystalline nature of SP and SP-g-PMAAs. The SEM images showed spherical or polyhedral smooth surface for the starch. After modification, SP and SP-g-PMAAs exhibited distorted and rougher surfaces which are assumed to be good for adsorption. The dual modification produced phosphate and carboxylic groups on the starch backbone. The phosphate and carboxylic groups have high tendency to make hydrogen bonding with phenol. The comparative adsorption studies of NS, SP and SP-g-PMAAs were checked for phenol. The experimental results showed adsorption efficiencies of 0.022 g/g, 0.082 g/g, 0.100 g/g, 0.148 g/g and 0.151 g/g for NS, SP, SP-g-PMAA1, SP-g-PMAA2 and SP-g-PMAA3, respectively. The following findings revealed that dual modification enhanced the adsorption ability of NS.

Phenylboronic acids (PBAs) have gained considerable interest in recent years due to their recognition for diol-containing molecules such as glucose. Their response to the elevated glucose concentrations can be reported by measuring the change in the size or optical properties of polymers-bearing PBAs. In this context, fast response and good mechanical properties are crucial factors for constructing glucose-responsive sensors. Toward this goal, we have synthesized glucose-responsive nanostructured gels (NSGs) using 3-acrylamidophenylboronic acid and N-isopropylacrylamide. Herein, activated nanogels with controllable size were prepared and used as nano-cross-linkers. The prepared NSGs showed glucose-responsiveness in a remarkable concentration-dependent manner, exhibited high elasticity upon compression and slicing and resisted high level of deformation such as bending, twisting and stretching.

Plant pathogenic bacteria engage in an ongoing struggle for survival. Gram negative phytopathogenic prokaryotes deploy type III secretion system to deliver effector proteins into plant cells to manipulate the host cellular environment. In many cases, the targets of these effector proteins are unknown. The bacterial blight pathogen, Xanthomonas oryzae pv. oryzae (Xoo), causes a devastating disease in rice and the Xoo-rice interaction is an example of the ongoing evolutionary battle between plants and pathogens. In this study, we show that an effector XopL from Xoo exhibits E3 ubiquitin ligase activity and induces cell death in the nonhost Nicotiana benthamiana (Nb). Through yeast two-hybrid, co-immunoprecipitation, and biomolecular fluorescence complementation assays, it was shown that XopL interacts with ferredoxin (NbFd), an electron transport molecule in plant chloroplasts. XopL induced defense-related response in Nb and specifically targeted NbFd for ubiquitination and ubiquitin-mediated degradation, a process that increased the production of reactive oxygen species (ROS). This study demonstrates the ubiquitination and degradation of NbFd as a result of XopL activity, which further illustrates the tremendous functional diversity in Xanthomonas effector proteins.

Antifogging agents are very important for use on agricultural films. Fogging reduces crop yield and causes other negative effects. To overcome fogging problems on agricultural films, several approaches including surface coating and reactive extrusion methods have been used. To date, researchers have designed a variety of agents to prepare antifogging films. The mechanism and rules for the composition of such agents have also been reported. However, reported antifogging films do not exhibit satisfactory results. Therefore, antifogging methods require further improvement. In this review, different preparation methods for antifogging agents and films are summarized, along with the advantages and disadvantages of each method. Moreover, test methods for antifogging performance are introduced.

In this article, we study existence and uniqueness of a class of highly non-linear boundary value problem of fractional order differential equations. The concerned problem is investigated by means of classical fixed point theorem for the mentioned requirements. The Ulam–Hyer’s stability is also established for the class of fractional differential equations. Appropriate example is also provided which demonstrate the applicability of our results.

In this paper, we apply a hybrid method due to coupling the Laplace transform with the Adomian decomposition method (LADM) for solving nonlinear fractional differential equations that appear in the model of Keller-Segel equations with one dimension. We explain the adopted method is with several examples. It turns out that the reliability of LADM and the reductions in computations show that LADM is widely applicable. We also compare our results with the results of homotopy decomposition method (HDM).