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CO2 gas is a greenhouse gas that causes global warming. Greenhouse gases are gases in the atmosphere that can absorb and reflect infrared radiation from the Earth's surface. Currently, the energy demand still depends on fossil fuels. On the other hand, CO2 emissions from burning fossil fuels continue to increase and contribute as greenhouse gases to the atmosphere. CO2 capture is an effort to reduce the burden of CO2 emissions into the atmosphere and is part of the Carbon, Capture, and Storage (CCS) protocol. The CO2 absorption process applied in the chemical industry is one of the CO2 absorptions using NaOH and Na2CO3 solutions as absorbents. This research aims to determine the effect of absorbent flow rate on the percentage of absorbed CO2. The method used in this research is the SLR (Systematic Literature Review) method to identify all available research. The absorbent flow rate variations used are 1 liter/minute, 1.5 liters/minute, 2 liters/minute, 2.5 liters/minute, and 3 liters/minute. The absorption process using NaOH absorbent is capable of absorbing CO2 gas with a maximum absorption of 95.52% and a minimum of 79.14%. Meanwhile, in the Na2CO3 absorbent, it is capable of absorbing CO2 gas with a maximum amount absorbed of 72.45% and a minimum of 35.47%.

Integrating solar energy into a coal-fired power plant is a promising way to reduce auxiliary load and numerous environmental issues related to the coal-based power generation sector. This paper will discuss the annual performance of PV plant 689 kWp at ash disposal that integrated into 615 MW coal-fired power plant PT xxx, including an estimate of total potential energy that can be generated; analysis of auxiliary load to improve performance and decreasing pollutant emissions by coal consumption reduction. The PV Plant has been operated for at least 2 years, built on an area of 5,000m2, is an On-grid PV Plant system with 11 grid Inverters and has 2,120 solar modules installed. Based on the simulation using Helioscope software, it can generate electrical energy up to 977,442 kWh per year with a performance ratio of 79.3%. The result of the PV plant utilization evaluation shows the amount of electrical energy produced is 1,096,105 kWh in 2021, above the estimation from the simulation. This result means auxiliary power load was decreasing by 0.4932%, It is also considered to be able to save the use of 263.065 kiloliters per year of diesel and also save the use of coal up to 386.634 tons or equivalent to 0.007% coal consumption per year. From an environmental point of view, it is also assessed to reduce CO2 emissions equivalent to 920.729 tons/year and the equivalent of planting 4,602 trees per year.

Ferrocene (Fc)-based polymers have promising application in burning rate catalysts (BRCs) for solid composite propellants, and some of them have already been practically used. However, they have some drawbacks such as high migration during a long-time storage. Copolymers of poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-glycidyl methacrylic acid)s (P(FHEMA-co-GMA)s) were synthesized to overcome the migration problem of Fc-based BRCs as well as to boost the burning rate (BR) of ammonium perchlorate (AP)-based propellants. The structures of the obtained P(FHEMA-co-GMA)s were confirmed by proton nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FT-IR) spectroscopy. Cyclic voltammetry (CV) method was used to study their electrochemical behavior, and the P(FHEMA-co-GMA)s showed redox behavior for the existence of the Fc units. Because of the formation of integrated network structures, the P(FHEMA-co-GMA)s have good anti-migration performances. The BR catalytic property of P(FHEMA-co-GMA)s were investigated by thermogravimetry (TG) and differential thermogravimetry (DTG). They showed competent catalytic effects on the thermal decomposition of AP.

The current work reports a simple and cost-effective green method for fabricating MEL@Fe3O4NPs and GA/Ag–Fe3O4@MEL-NCs using microbial glycolipid mannosylerythritol lipids (MEL) and gum arabic. The prepared bionanocomposites were characterized using X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared spectroscopy (FTIR). TEM analysis of the bionanocomposites showed the spherical shape particles. Furthermore, the GA/Ag–Fe3O4@MEL-NCs showed potent antioxidant efficacy against DPPH, ABTS, and FRAP (IC50; 62.95, 70.63, and 63.26 µg/mL, respectively). Moreover, the IC50 values of biosynthesized MEL@Fe3O4 and GA/Ag–Fe3O4@MEL-NCs for inhibition human liver cancer cells were 119.35 and 85.18 µg/mL, respectively, indicating its greater efficacy in killing cancer cells. As-prepared GA/Ag–Fe3O4@MEL-NCs may have great potential application in the field of pharmaceuticals as nanoantioxidants and anti-hepatocarcinoma.

Among metals, AgNWs are considered to be excellent materials for use in surface enhancement Raman spectroscopic (SERS) sensing due to their superior electrical properties, strong electromagnetic field generation and strong enhancement intensity. Herein, we used a simple conventional polyol method to synthesize AgNWs feasibly in 40 min under Ar inert atmosphere without using any inorganic salts; only high molecular weight PVP was used as a capping and growth controlling agent, while ethylene glycol was used as a solvent as well as a reducing agent and silver nitrate was used as a Ag source. The polyol-synthesized smooth surface AgNWs were then subjected to chemical etching using aqueous ammonia and 30% hydrogen peroxide as etchant materials, and corrugated surface AgNWs were successfully prepared. The as-synthesized corrugated surface AgNWs were used as surface enhancement materials to increase the intensity of Raman signals, and the surface enhancement properties of the corrugated surface AgNWs were studied using rhodamine 6G as a probe molecule via SERS sensing. The results showed that the AgNWs were successfully prepared in 40 min of reaction; also, corrugated surface AgNWs were prepared, and their corrugated surfaces resulted in high intensity SERS signals.

In recent years, synthetic polymer materials have become a research hotspot in the field of drug delivery. Compared with natural polymer materials, synthetic polymer materials have more flexible structural adjustability, and can be designed to obtain clinically required delivery vehicles. Polyphosphazenes are one of the most promising biomedical materials in the future due to their controllable degradation properties and structural flexibility. These materials can be designed by controlling the hydrophilic and hydrophobic balance, introducing functional groups or drugs to form different forms of administration, such as nanoparticles, polyphosphazene-drug conjugates, injectable hydrogels, coatings, etc. In addition, the flexible backbone of polyphosphazenes and the flexibility of substitution enable them to meet researchers' design requirements in terms of stereochemistry, nanostructures, and topologies. At present, researchers have achieved a lot of successful practices in the field of targeted delivery of anticancer drugs/proteins/genes, bone tissue engineering repair, cell imaging tracking, photothermal therapy, and immunologic preparations. This review provides a summary of the progress of the recent 10 years of polyphosphazene-based drug delivery systems in terms of of chemical structure and functions.

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.

Silver nanowires (AgNWs) with high uniformity and controlled morphology were synthesized by employing silver nitrate as precursor and ethylene glycol as reducing agent and solvent. Polyvinyl pyrrolidone (PVP) was used as growth controlling agent and the synthetic process was carried out in salt free environment. The effect of reaction parameters like concentration of AgNO3 and the reaction temperature on the final morphology of AgNWs was studied. AgNWs obtained by changing different conditions were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM), selected area electron diffraction pattern (SAED), X-ray diffraction (XRD) and UV–Vis spectroscopy. Synthesized AgNWs were coated on polyethylene terephthalate substrate by spin coating method to make thin conductive flexible film. The silver nanowires film was found to have a sheet resistance of 6.82 Ω/sq.

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.

Three novel polymers (P(FHEMA-co-MAAT)s) having redox and photoresponsive moieties were prepared by free radical polymerization. The structures and molecular weights of the synthesized copolymers were characterized by nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC) respectively. Thermal properties, optical features and electroactive properties were studied with the help of thermogravimetric (TG), differential thermogravimetric (DTG) analysis, ultraviolet-visible spectroscopy (UV-vis) and cyclic voltammetry (CV). It was seen that synthesized copolymers had excellent redox and photoresponsive properties. These results exhibited that these polymers can be applied further for redox/photo responsive information storage devices.

In past few years, phenylboronic acids (PBAs) have attracted researcher's attention due to their unique responsiveness towards diol-containing molecules such as glucose. This property allows hydrogel-bearing PBAs potentially to serve as an alternative for glucose-sensing and insulin-delivery systems. This review provides an outlook on the binding mechanism of PBA moieties with diols and the approaches to increase their binding selectivity and response for glucose molecules. The preparation methods and strategies of hydrogel-bearing PBA moieties along with their properties are discussed. In the last section, their applications in glucose-sensing and insulin-regulatory systems are described.

Synthesis of silver nanowires got much attention of researchers due to their promising applications in various fields of nanoelectronic devices. Many research articles focusing on silver nanowires synthesis have been reported since past decade. A number of techniques have been applied for successful synthesis of silver nanowires. Solution-based polyol process was proved as a dominant approach to the fabrication of silver nanowires with homogeneity and high aspect ratio. Various inorganic salts have been used in solution-based polyol synthesis of silver nanowires which play a key role in controlling the final morphology of silver nanowires and lead to uniform growth of silver nanowires. The different experimental parameters have been studied, which directly influence the final morphology of silver nanowires. The research on the development of an efficient synthesis approach of silver nanowires is still in progress to accomplish the need of advanced technology for controlled morphology and highest aspect ratio of silver nanowires. Moreover, the unique applications of silver nanowires in conducting polymers composites were discussed.

The Burning rate of a solid propellant predominantly influences its internal ballistic behavior and it has been well known that incorporation of small quantities of certain classes of organic and inorganic substance to a propellant can drastically alter its burning rate characteristics. The inclusion of energetic materials and burning rate catalysts (BRCs) from the metallocene family (e.g., ferrocene (Fc) and 2,2-bis (ethylferrocenyl) propane also known as catocene (Cat)) has been a promising avenue for efficiently increasing the burning rate of propellants. Fc-based materials are dominantly used as burning rate catalysts in solid propellants because of their low volatility, higher compatibility with organic binders, microscopic homogeneities in distribution, broad range of burning rate adjustments, better ignitability and distinct catalytic features. However, in solid composite propellants, Fc-based polymers and derivatives show undesired properties of high migration, that is travelling out from propellant grain to surrounding insulation material on prolong storage, evaporation or sublimation loss during processing and curing as well as phase separation by crystallization in low-temperature applications, limiting their application as BRCs. This article outlines the latest synthetic advancements in the field of Fc-based BRCs, as well as highlighting their catalytic and anti-migration mechanisms.

Different hydrogels of poly(acrylamide-co-3-acrylamido phenylboronic acid-co-chitosan grafted maleic acid) (P(AM-co-AAPBA-co-CSMA)s) were synthesized using poly(ethylene glycol) diacrylate (PEGDA) as a crosslinker to serve for glucose sensing and insulin delivery. The structure and morphology of the hydrogels, named as CSPBA were studied by FTIR and SEM, while the mechanical properties were tested using dynamic mechanical analysis (DMA) and universal testing machine. The prepared hydrogels shrinked at low glucose concentration due to the 2:1 boronate-glucose binding, and swelled at high glucose concentration because of 1:1 boronate-glucose complexation. Both binding mechanisms are useful for glucose sensing and insulin delivery. The integration of CSMA into hydrogels network not only enhanced the response to glucose at physiological pH, but also improved the mechanical properties and increased the encapsulation efficiency of the prepared hydrogels. These CSPBA may find potential as implantable hydrogels in applications were continuous glucose monitoring and controlled release is beneficial.

Drug combination therapy is an emerging technology to treat the diseases which are still annoyance to human being. Combination of two or more drugs can deal with diseases in a better way. Various different techniques have been introduced which can deliver combination of drugs in a safe and more controlled manner. In our research, we prepared polyphosphazene-based blend microspheres which can deliver two different drugs in a much sustained manner for long time. “Acetamidophenol,” commonly used drug, was attached to the polyphosphazene main chain to produce drug–polymer conjugates, and these were then blended with PMMA in different ratios to fabricate the microspheres of variable and controlled size. Another anticancer drug “camptothecin” was loaded in these microspheres to fabricate dual-drug-loaded microsphere. Furthermore, in vitro drug release behaviors of fabricated microspheres were also demonstrated.

With the development in the modern technologies such as telecommunication instruments and scientific electronic devices, large amount of the electromagnetic radiations are produced, which lead to harmful effect on the highly sensitive electronic devices as well as on the health of human beings. To minimize the effect of electromagnetic radiations produced by different technologies, more efficient shielding materials are required which must be cost-effective, lightweight and good corrosion resistive. In this review, we focused on the shielding materials based on composites of carbon nanotubes and graphene. The typical surface modification of carbon nanotubes and graphene to optimize their interactions with polymers matrix has also summarized. It was found that the composites based on these carbon fillers were more efficient for electromagnetic interference shielding due to their unique properties (i.e., superior electrical, mechanical and thermal) together with lightweight, easy processing. Hence, the carbon nanotubes and graphene-based composites are excellent shielding materials against the electromagnetic radiations.

This review article provides an overview of the contemporary research based on a tailor-made technique to understand the paramagnetic behavior of different polymer classes. The ubiquity of free radicals, including biradicals, triplet states, and point defects in polymer systems, has made EPR spectroscopy an indispensable tool in polymer science among other mainstream analytical techniques. The scope of EPR spectroscopy has broadened particularly due to the growing impulse to produce polymers with enhanced stability, to follow the charge transfer process in conducting polymers, to decipher the complex nanoscale dynamics of polymers, to fathom out the reaction mechanisms and kinetics of complex polymer reactions in a more facile way, and to carry out comprehensive structural and conformational analyses. Recent studies have hinted at the effectiveness of EPR spectroscopy in collecting data with sub-nanometer spatial resolution to decipher intrinsic intricacies, while keeping the pristine geometry unperturbed, a task yet not achievable with other conventional techniques. EPR spectroscopy is being applied in polymer science in multifarious ways, including, but not limited to, exploring the structure, conformation, and dynamics of polymer chain segments, degradation or defect studies, charge transfer properties, kinetics and reaction mechanisms especially of free radical polymerization reactions, and EPR imaging of the polymer matrix. A recent surge in its applications indicates that EPR spectroscopy is going to make a profound impact in the field of polymer science in upcoming years.

In this study, a variety of nanocomposites, namely, MEL@AgNPs, MEL@ZnONPs, and Ag–ZnO/MEL/GA were biosynthesized using MEL and gum arabic to serve in biomedical applications. The synthesized nanocomposites were examined using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and FTIR spectroscopy. The physicochemical properties and biomedical activities of the synthesized nanocomposites were investigated. The Ag–ZnO/MEL/GA nanocomposites showed greater antidiabetic activity against α-amylase and α-glucosidase, and higher antibacterial activity compared to MEL@AgNPs and MEL@ZnONPs. Furthermore, HepG2 cells were exposed to MEL@AgNPs, MEL@ZnONPs, and Ag–ZnO/MEL/GA nanocomposites for 24 h and their IC50 values were 63.25, 26.91 and 28.97 μg mL−1 (P < 0.05), respectively. According to this comparative study, it is apparent that the Ag–ZnO/MEL/GA nanocomposites have a great potential to serve as antitumor agents against HepG2, and antidiabetic and antibacterial agents.

Understanding segmental dynamics of polymer chains is important to decipher the microscopic behavior in order to modulate the bulk properties of polymers. Study of electron spin resonance (ESR) spectroscopy of polymer chain segments is useful to understand internal dynamics of polymer chains in solution. In this paper, poly(oligoethylene glycol methacrylate-co-2,2,6,6-tetramethyl piperidin-4-yl methacrylate)s, OEG-TMPMs, were synthesized. The synthesized OEG-TMPMs were characterized by nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric (TG) techniques. The TMPM moiety in OEG-TMPMs was oxidized to 2,2,6,6-tetramethyl-1-piperinidyloxy-4-yl methacrylate (TMP) to generate nitroxide radicals. These nitroxide radical-containing OEG-TMPs were analyzed with Fourier transform-infrared (FT-IR) spectroscopy, cyclic voltammetry (CV) and ESR spectroscopy. The effect of side chain length on the segmental mobility of OEG-TMPs was studied. The results showed that the longer pendent chains as in OEG-TMP-4 imparted higher flexibility to the backbone of the polymer and increased rotational freedom of nitroxide radicals as compared to restricted mobility in the case of shorter polymer side chains.

A series of copolymers of poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-methacrylic acid)s (P(FHEMA-co-MAA)s) were synthesized as burning rate catalysts (BRCs). Their structures were verified using proton nuclear magnetic resonance (1H NMR) and Fourier transforms infrared (FT-IR) spectroscopy. The electrochemical behavior of P(FHEMA-co-MAA)s was investigated by cyclic voltammetry (CV). The CV results indicated that P(FHEMA-co-MAA)s showed redox behavior. Anti-migration test proved that P(FHEMA-co-MAA)s possesses better anti-migration properties than ferrocene (Fc) and 2, 2-bis (ethylferrocenyl) propane (Catocene). The burning rate (BR) catalytic effect of P(FHEMA-co-MAA)s on thermal decomposition of AP was examined through thermogravimetry (TG) and differential thermogravimetry (DTG). P(FHEMA-co-MAA)s were found to have high catalytic effects in accelerating thermal decomposition of ammonium perchlorate (AP).

Different glucose-responsive nanogels of N-isopropylacrylamide (NIPAM) and 4-(1,6-dioxo-2,5-diaza-7-oxamyl) phenylboronic acid (DDOPBA) were synthesized using dextran-grafted maleic acid (Dex-MA) as a crosslinker. The formed nanogels (P(NIPAM-co-Dex-co-DDOPBA)s) were verified by 1H NMR, TEM, DLS and X-ray photoelectron spectroscopy (XPS). The incorporation of DDOPBA provided a remarkable sensitivity towards glucose in physiological pH due to the existence of electron-withdrawing group in its structure. Similarly, the hydrophilic Dex-MA modulated the temperature-sensitivity near physiological temperature. The nanogels exhibited high insulin loading capacity and encapsulation efficiency and the in vitro release profiles demonstrated a glucose dependant release of the payload at physiological pH and temperature.

Different copolymers (poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-methacrylo-4-aminoazobenzene-co-methacrylic acid)s) (P(FHEMA-co-MAZO-co-MAA)s) were synthesized and their different properties were analyzed in this work. Methacrylic acid was introduced as a side group to possibly affect the photostability. The synthesized copolymers were characterized by nuclear magnetic resonance (1H NMR) spectroscopy and gel permeation chromatography (GPC). Thermal studies were performed by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) analysis, which showed that the copolymers were thermally stable under the operating conditions of the information storage devices. Redox studies and photoresponsive studies were performed by CV technique and UV/vis spectroscopy which showed that these copolymers contained good redox and photoresponsive properties. The obtained results paved the way towards the four states information storage of the materials.

Understanding the segmental dynamics of polymer chains is cardinal to decipher the microscopic behaviour in order to modulate the bulk properties of polymers. The study of electron spin resonance (...

Five ferrocene (Fc)-based compounds (HQ-Fcs) were synthesized by the condensation reaction of ferrocenecarbonyl chloride with corresponding hydroquinone derivatives. Nuclear magnetic resonance (1H NMR), and Fourier transform infrared (FT-IR) were used as evidence for the synthesis of HQ-Fcs. The electrochemical properties of HQ-Fcs were investigated by cyclic voltammetry (CV) and suggested that these compounds exhibited redox behavior due to ferrocene groups. The burning rate catalytic effect of HQ-Fcs was examined by Thermogravimetric (TG) and differential Thermogravimetric (DTG) techniques. Thermal analysis results indicated that HQ-Fcs were thermally stable and have better burning rate catalytic effects in accelerating thermal decomposition of AP. Anti-migration behavior of HQ-Fcs in comparison to commonly used 2,2-bis (ethylferrocenyl) propane (catocene) and Fc was evaluated. It was observed that HQ-Fcs delivered excellent anti-migration performances than catocene and Fc.