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Silver nanoparticles are known to have antimicrobial properties. In the present paper, antibacterial activity of biosynthesized silver nanoparticles coated on low density poly ethylene films was evaluated against Escherichia coli as the representative organism. Silver nanoparticles were biosynthesized using banana peel extract as the reducing agent and characterized by means of UV–Visible spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-ray analyses. Formation of silver nanoparticles was confirmed by the Surface Plasmon Resonance spectrum with absorption maxima at 431 nm. Particles were seen to be highly polydispersed with the average size in the range of 50–390 nm. Presence of elemental silver was confirmed by the Energy dispersive X-ray spectroscopy analysis. Biosynthesized silver nanoparticles showed excellent antibacterial activity against Escherichia coli in the agar well diffusion test, with the zone of inhibition diameter measuring 19 mm. The silver nanoparticle coated low density poly ethylene film was prepared successfully and our antimicrobial studies revealed that the coated films declined the growth profile of bacteria starting from the log phase. Hence biosynthesized silver nanoparticles incorporated low density poly ethylene films can be suggested as an active packaging material for food packaging after further characterization and migration studies.

Soft gamma ray irradiation is done on Silver nano colloids prepared using Pepper Nigrum as reducing and stabilizing agent. Change in surface morphology and the structure of the colloid is obtained from Transmission Electron Microscope images and Selected area Electron Diffractogram. Morphology of the gamma irradiated sample is devoid of nano particle clusters and the Selected Area Electron Diffraction pattern confirms the crystal nature as face centered cubic structure of nano silver. UV–visible spectroscopic analysis gives the absorption peaks in the green region. Gamma irradiation results in the reduction in peak intensity without any change in wavelength. A statistical approach is done on treating the gamma irradiated colloidal sample with the as prepared silver nano colloid for measuring the area of affecting fungal infection on a potato-agar medium. It is found that the fungal growth is declined rapidly with the introduction of gamma irradiated silver nano colloid than the as prepared colloid.

Xenon capture and Xe/Kr separation are important processes in industry. For instance, Xe/Kr separation is an indispensable step in recycle and treatment of nuclear fuel emission. Among different separation methods, selectively adsorb gas molecules using porous materials is a promising way to reduce the high energy consumption in traditional cryogenic distillation. However, many reported adsorbents still face the challenges of: i) poor separation property at low Xe/Kr concentrations; ii) insufficient retention volumes, which influence the viability of whole process. In this work, we present a stable covalent organic polymer, i.e., COP-14, showing promising potential for Xe/Kr separiton. In dynamic breakthrough experiments, COP-14 successfully separates low concentration Xe (350 ppm) and Kr (35 ppm) from target gas mixtures. Meanwhile, the xenon retention volume per gram (1700 mL g-1 at 298 K) of COP-14 in dynamics absorption process achieves 3.8 times of benchmark active carbon. The good performance of the newly devloped COP-14 mainly from its rich nitrogen sites and suitable pore size with xenon molecues. The promising results of COP-14 on Xe/Kr separation in this work provide a promising way for designing efficient Xe/Kr separation mateirals.

To obtain a long-term stable operation of the hollow fiber membrane for using in membrane contact absorption of carbon dioxide (CO2), hybrid polyvinylidene fluoride-silica-hexadecyltrimethoxysilane (PVDF-SiO2-HDTMS) membrane were fabricated via the non-solvent induced phase-inversion method. The surface properties, performance characteristics and long-term stable operation performance of the prepared membranes were compared and analyzed. The results show the outer surface of the prepared membranes exhibited superhydrophobicity because of the formation of rough nano-scale microstructures and the low surface free energy. Due to the addition of inorganic nanoparticles, the mechanical strength of PVDF-SiO2-HDTMS membranes were improved. The long-term stable operation experiments were carried out with the inlet gas (CO2/N2 = 19/81, v/v) at a flow rate of 20 mL/min and the absorbent liquid (1 mol/L DEA) at a flow rate of 50 mL/min. And the result showed that the mass transfer flux of PVDF-SiO2-HDTMS membrane decreased from the initial value of 2.39×10-3 mol/m2s to 2.31×10-3 mol/m2s, which was a decrease of 3% after 20 days. The main benefit is the addition of inorganic nanoparticles, which have strong chemical resistance and high hydrophobicity, thereby preventing structural damage and pore wetting of the membrane. PVDF-SiO2-HDTMS membrane exhibits excellent long-term stable operation performance of CO2.

Adsorption process is considered to be the most promising alternative for the CO2 capture to the traditional energy-intensive amine absorption process, and the development of feasible and efficient CO2 adsorbents is still a challenge. In this work, the NiO@USY (ultrastable Y) composites with different NiO loadings were prepared for the CO2 adsorption using Ni(NO3)2 as the precursor. The composites were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, nitrogen adsorption–desorption test, scanning electron microscopy analysis, and thermogravimetric analysis, and were evaluated for the CO2 adsorption capacity, CO2/N2 adsorption selectivity and CO2 cycle adsorption capacity. The characterization results show that after the activation at 423 K, the Ni(NO3)2 species were well dispersed into the surface of zeolite USY, and after the further activation at 823 K, Ni(NO3)2 could be converted into highly dispersed NiO. The adsorption results show that the presence of the active component NiO plays an important role in improving the CO2 adsorption performance, and the NiO@USY composite with a NiO loading of 1.5 mmol·g−1 USY support displays a high adsorption capacity and adsorption selectivity for CO2, and shows a good cycle stability. In addition, the Clausius–Clapeyron equation was used to evaluate the isosteric heat of adsorption of CO2 on the NiO(1.5)@USY composite, and the heat of adsorption was 17.39–38.34 kJ·mol−1.

Natural gas hydrates can readily form in deep-water oil production processes and pose a great threat to the oil industry. Moreover, the coexistence of hydrate and asphaltene can result in more severe challenges to subsea flow assurance. In order to study the effects of asphaltene on hydrate growth at the oil–water interface, a series of micro-experiments were conducted in a self-made reactor, where hydrates nucleated and grew on the surface of a water droplet immersed in asphaltene-containing oil. Based on the micro-observations, the shape and growth rate of the hydrate shell formed at the oil–water interface were mainly investigated and the effects of asphaltene on hydrate growth were analyzed. According to the experimental results, the shape of the water droplet and the interfacial area changed significantly after the formation of the hydrate shell when the asphaltene concentration was higher than a certain value. A mechanism related to the reduction of the interfacial tension caused by the absorption of asphaltenes on the interface was proposed for illustration. Moreover, the growth rate of the hydrate shell decreased significantly with the increasing asphaltene concentration under experimental conditions. The conclusions of this paper could provide preliminary insight how asphaltene affect hydrate growth at the oil–water interface.

It is of significance to investigate deeply the hydrodynamic features of the bubble contaminated by impurities in view of the fact that the industrial liquid is difficult to keep absolutely pure. On the basis of the finite volume method, the bubble interface contaminated by the surfactant (1-pentanol) is achieved through solving the concentration transport equations in liquid and along the bubble interface, and solving the absorption and desorption equation at the bubble interface. And the three-dimensional momentum equation is solved at the same time. It is investigated in detail on the influence of interfacial contamination degrees (described with the cap angle θ) on hydrodynamic characteristics of the spherical bubble when the bubble Reynolds number (Re) is larger than 200. The θ is realized by changing the surfactant concentration (C0) in liquid. The present results show that the hydrodynamic characteristics, such as interfacial concentration, interfacial shear stress, interfacial velocity and wake flow, are related to both Re and C0 for the contaminated bubble. When C0 is relatively low in liquid (i.e., the contamination degree of the bubble interface is relatively slight), the hydrodynamic characteristics of the bubble can still keep the 2D features even if Re>200. The decrease of θ or the increase of Re can promote the appearance of the unsteady wake flow. For the present investigation, when Re>200 and θ≤60°, the hydrodynamic characteristics of the bubble show the 3D phenomena, which indicates that axisymmetric model is no longer valid.

In the titanium dioxide industry, there is a lack of a low-cost and high-efficiency treatment method for chloride containing tail gas. In this paper, the removal of HCl from the titanium dioxide industry by gas cyclone-liquid jet separator was studied, while Ca(OH)2, Na2CO3, NaOH solution, and water were used as absorbents. This paper investigated the influence of gas cyclone-liquid jet separator’s various process parameters on the removal rate of hydrogen chloride gas. The mechanism of mass transfer in the process of removing hydrogen chloride was discussed, and the effect and feasibility of HCl gas removal in the gas cyclone-liquid jet absorption separator were studied. The results showd that the removal efficiency of hydrogen chloride maintained above 95%, up to 99.9%, and the total mass transfer coefficient reached 0.28 mol·m-3·s-1·kPa-1. Under the same conditions, the absorption effect and total mass transfer coefficient of weak basic absorption liquid can be greatly improved by increasing the flow rate of absorption liquid, but the absorption effect and total mass transfer coefficient of strong alkaline absorption liquid can’t be improved obviously. The larger the inlet gas volume, the higher the gas concentration, the lower the absorption efficiency and the lower the total volumetric mass transfer coefficient.

Polymer materials offer controllable structure-dependent performances in separation, catalysis and drug release. Their molecular structures can be precisely tailored to accept Li+ for energy storage applications. Here the design of sp2 carbon-based polyphenylene (PPH) with high lithium-ion uptakes and long-term stability is reported. Linear-PPH (L-PPH) exceeds the performance of crosslink-PPH (C-PPH), due to the fact that it has an ordered lamellar structure, promoting the Li+ intercalation/deintercalation channel. The L-PPH cell shows a clear charge and discharge plateau at 0.35 and 0.15 V vs. Li+/Li, respectively, which is absent in the C-PPH cell. The Li+ storage capacity of L-PPH is five times that of the C-PPH. The reversible storage capacity is further improved to 261 mAh g−1 by functionalizing the L-PPH with the –SO3H groups. In addition, the Li-intercalated structures of C-PPH and L-PPH are investigated via near-edge X-ray absorption fine structure (NEXAFS), suggesting the high reversible Li+ –C C bond interaction at L-PPH. This strategy, based on new insight into sp2 functional groups, is the first step toward a molecular understanding of the structure storage-capacity relationship in sp2 carbon-based polymer.

The shale gas revolution and the carbon-neutrality goal are motivating the landscape toward the synthesis of value-added chemicals or fuels from underutilized ethane with the assistance of greenhouse gas CO2. Combining ethane aromatization with CO2 reduction offers an opportunity to directly produce liquid products for facile separation, storage, and transportation. In the present work, Fe/ZSM-5 catalysts showed promise in the simultaneous CO2 reduction and ethane aromatization at atmospheric pressure and 873 K. The catalysts were further investigated using X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) measurements under in-situ conditions, indicating that most of Fe species existed in the form of Fe oxides and a portion of Fe was incorporated into the ZSM-5 framework generating Lewis acid sites. Both types of Fe species remained almost unchanged under reaction conditions, contributing to an enhanced aromatization activity of Fe/ZSM-5. The effects of CO2 and steam on the acid sites and in turn aromatization activity were also investigated by transient studies, which exhibited a reversible modification behavior. Moreover, CO2 was identified to be critical to enhance coke resistance and in turn catalyst stability. This work highlights the feasibility of using CO2 to assist the upgrading of abundant ethane from shale gas to aromatics over non-precious Fe-based zeolite catalysts.

Specific interactions of yttrium and lanthanum ions with a fatty acid Langmuir monolayer were investigated using vibrational sum frequency spectroscopy. The trivalent ions were shown to interact with the charged form of the carboxylic acid group from nanomolar concentrations (

A simple and effective method for constructing highly efficient oxygen reduction catalysts with trace amount of isolated cobalt was firstly developed by the pyrolysis of Co-centered polyoxometalate@metal-organic framework (Co-POM@MOF). The Co-centered polyoxometalate ([CoW12O40]6−) was confined in the well-defined void space of ZIF-8 to achieve homogeneous dispersion of polyoxoanions, where the isolated Co centers were well surrounded by the W-O shell and ZIF-8 framework. The Co-POM@MOF-derived N-doping porous carbon (Co-W-NC) with trace cobalt content was facilely prepared by the pyrolysis of the Co-POM@MOF under Ar atmosphere. The single dispersion of polyoxoanions in the metal-organic framework with complete separation of Co center surrounding by W-O shell and ZIF-8 framework ensures the uniform dispersion of Co atoms, confirmed by the Fourier transform extended X-ray absorption fine structure measurement. The Co-W-NC composite catalysts exhibit high performance for oxygen reduction reactions with a half-wave potential of 0.835 V in 0.1 mol/L KOH solution with excellent durability, which is much superior to that of the control samples derived from the [PW12O40]@ZIF-8, and the commercial Pt/C. This work highlights a new insight for constructing highly efficient catalysts via the introduction of metal-centered polyoxometalate into metal-organic framework following the high temperature treatment process.

An efficient method for prediction in the capture of SO2 from flue gas by imidazolium ionic liquids was reported, where the concentration of SO2 is 2000 ppm. On the basis of quantitative calculations through a combination of Langmuir simulation, theoretical calculation and quantum chemical method, SO2 absorption and desorption performance from flue gas by twelve kinds of imidazolium ionic liquids with different anions were designed and predicted. Then, among them, five kinds of imidazolium ionic liquids were chosen and prepared to investigate their behavior of SO2 absorption capacity, desorption residue, and available absorption capacity. The results indicated that the experimental values were in good agreement with the predicted values. Thus, an ideal ionic liquid [Emim][Tetz] was obtained through the predictive method for the capture of SO2 of 2000 ppm, which showed high available absorption capacity of 0.24 g SO2 per g ionic liquid and excellent reversibility.

Ozonation process alone is not sufficient to remove both the SO2 and NOX gases, when treated simultaneously. Therefore in this work, a suitable technique to remove SO2 and NOX simultaneously has been evaluated using combination of O3, H2O2 and a solid catalyst. OMS-2, a manganese based catalyst have been incorporated with O3 and H2O2 for enhanced radical generation. This preferably enhances the oxidation of SO2 and NOx species in aqueous medium simultaneously. The role of some important process parameters have been tested on the performance of SO2 and NOX absorption. To get the maximum removal of SO2 and NOX, the neutral pH, temperature close to 300–320 K, and H2O2 at 0.2 mol L−1 concentrations was found to be the optimum condition. The use of catalyst (approximately 2 g L−1) + O3 + H2O2 shows promising results on the removal of SO2 and NOX. In addition to that, the kinetics of the catalytic ozonation and peroxone removal of SO2 and NO2 has been evaluated. The cost estimation study for the ozone and peroxone based catalytic processes has been presented with comparison of the respective flue gas %removal.

Strontium titanate (SrTiO3) nanocubes were prepared via the solvothermal method in an isopropanol-water system, using cetyltrimethylammonium bromide (CTAB) as a capping agent and tert-butylamine (TBA) as a mineralizer. We found that the presence of TBA produced a synergistic effect in the nucleation and growth of SrTiO3 in the solution, which enabled control over the formation of well-defined cubic particles. X-ray diffraction patterns of SrTiO3, synthesized with the addition of 1 mol of TBA, showed a perovskite structure with high crystallinity. The presence of specific absorption peaks in the fourier-transform infrared (FTIR) spectrum confirmed the existence of CTAB and TBA on the surface of the particles. Transmission electron microscope (TEM) images showed that the sharp-edged cubic particles had narrow size distributions, and selected area electron diffraction (SAED) patterns indicated a high crystallinity. An increase in electrical conductivity values was found in the bulk samples with regular nanocube particles compared to those of non-regular nanocubes.

The current works report the bio-efficacy of Pimenta dioica leaf derived silver nanoparticles (Pd@AgNPs) and leaf extract obtained trough different solvents against the larvae of malaria, filarial and dengue vectors. Synthesis of silver nanoparticles (AgNPs) was done by adding 10 ml of P. dioica leaf extract into 90 ml of 1 mM silver nitrate solution, a slow colour change was observed depicting the formation of AgNPs. Further, Pd@AgNPs was confirmed through Ultraviolet–visible spectroscopy which exhibited characteristic absorption peak at 422 nm wavelength. X-ray diffraction and selected area electron diffraction analysis confirmed monodispersed and crystalline nature of Pd@AgNPs with 32 nm an average size. Scanning electron microscopy and transmission electron microscopy showed the most of Pd@AgNPs were spherical and triangular in shape and energy-dispersive X-ray spectroscopy revealed silver elemental nature of nanoparticles. Zeta potential of Pd@AgNPs is highly negative which confirmed its stable nature. Pd@AgNPs showed prominent absorption peaks at 1015, 1047, 1243, 1634, 2347, 2373, 2697 and 3840 cm−1 which are corresponding to following compounds polysaccharides, carboxylic acids, water, alcohols, esters, ethers, amines, amides and phenol, respectively as reported by Fourier-transform infrared spectroscopy analysis. Gas chromatography–mass spectrometry and Liquid chromatography–mass spectrometry analysis revealed 39 and 70 compounds, respectively, which might be contributed for bio-reduction, capping, stabilization and larvicidal behavior of AgNPs. A comparable lethality (LC50 and LC90) was observed in case of Pd@AgNPs over leaf extract alone. The potential larvicidal activity of Pd@AgNPs was observed against the larvae of Aedes aegypti,(LC50, 2.605; LC90, 5.084 ppm) Anopheles stephensi (LC50, 3.269; LC90, 7.790 ppm) and Culex quinquefasciatus (LC50, 5.373; LC90, 14.738 ppm without affecting non-targeted organism, Mesocyclops thermocyclopoides after 72 hr of exposure. This study entails green chemistry behind synthesis of AgNPs which offers effective technique for mosquito control and other therapeutic applications.

Three kinds of heteroleptic Cu(I) complexes having a phenanthroline-based ligand acting as a chromophore and bearing benzoxazole, benzothiazole, and thiazole moieties were synthesized. Introduction...

CuO-reduced graphene oxide (rGO) composite is the potential candidate in the fields of optoelectronics and sensor applications. In the present work, we synthesized CuO nanosheets-rGO composites (CG) by a simple room-temperature preparation method. The prepared composites were named as CG1 (without any surfactant), CG2 (with polyethyleneglycol-400), and CG3 (polyvinylpyrrolidone). The equal intensity of (002,111)/(200,111) patterns in XRD (monoclinic CuO), double absorption peaks in UV–Vis spectra at 263 nm and 294 nm, and the FE-SEM images are evidenced for the sheet-like morphology of CuO. The FT-IR bands appeared at 547 and 596 cm−1 for the Cu–O vibrations. Micro-Raman studies also evidenced the formation of CuO-rGO structures. CG3 has larger sheets compared to others due to the interaction of long-chain PVP with rGO as well as CuO. The peak at 933.5 eV in XPS spectrum of CG1 confirms the presence of CuO in the sample.

Water is vital for the human existence. It has a fundamental role for the economic development and that of the human civilization due to its usage in various sectors namely industry and agriculture. This vital resource is known for its high fragility. Therefore, we have to find effective tools to protect it from pollution. Colorings are used in many industrial sections such as textile dye, paper, silk, and in many nutritional and beauty industries. Colorings are known to be toxic substances that are persistent in the environment; they need physico-chemical techniques for their degradation. Therefore, this study aims at valorizing the Algerian Clay in order to increase its retention capacities of the coloring Bemacid Yellow (BY) through the modification of the Clay character (sodic). Our materials have been characterized with FTIR, BET, and DRX. The BY absorption study on our bentonite has been verified by the study of certain parameters such as: contact time, pH solution, and the absorbent mass. These experiences showed that the Sodic Clay (SC) has a maximal capacity of adsorption at 160 mg/g. The study of the absorption kinetics showed that BY elimination follows the second order model with an intraparticular diffusion. In conclusion, the Algerian Clay presents very significant absorbent properties and may be used in the depollution of textile industries waste water.

With the global dye pollution situation becoming severe, a highly promising material is needed to purify water to safeguard ecological stability and public health. Studies have shown that semiconductor oxides are capable of generating a large number of photogenerated carriers under visible light irradiation as a way to degrade toxic dyes in wastewater. In this paper, CuO films were synthesized on indium tin oxide-coated glass substrates by ionic liquid-assisted electrodeposition. The samples were characterized by field emission scanning electron microscopy, X-ray diffraction, ultraviolet visible spectrophotometer and energy-dispersive spectrometer. The effects of ionic liquid concentration, electrodeposition parameters and annealing temperature on the structure and properties of CuO films were investigated in detail, as well as an in-depth analysis of the mechanism of the interaction between methylene blue and CuO films. The experimental results show that ionic liquids as reaction media, CuO films modified with ionic liquid have smoother surface and uniform thickness, and their smaller crystal size and uniformly distributed particles can provide more active reaction sites. The CuO film prepared under the optimal conditions has stable absorption and response performance to light, and the degradation rate of methylene blue reached 95% in 180 min, showing good ability to degrade organic matter in wastewater. Therefore, the CuO films prepared by ionic liquid-assisted electrodeposition can be used as an effective photocatalyst for the removal of organic dyes from wastewater to ensure water safety and have potential practical applications for human health.

Synergistically tuned noble metals and intentionally formed complex heterostructured nanomaterials can enhance the required application effectiveness but at the cost of tedious synthesis routes, expensive chemicals, and sophisticated instruments. To overcome such demerits, herein, we report on the oleic acid-mediated convenient co-precipitation route using water–hexane as a biphasic solvent for CuO synthesis in the form of nano feathers (CuO-NF), solid/hollow hexagonal thin sheets (CuO-HS), and mega sheets (CuO-MS) at room temperature. The exotic CuO nanoarchitectures achieved were tested and compared with control samples (CuO-IS) for CO2 sensing, natural sunlight induced dye degradation, and catalytic CO2 reduction. Among the various CuO nanostructures synthesized, CuO-HS depicted higher oxygen deficiency, electronic conductivity, and visible light absorption. Most of the solid/hollow hexagonal thin sheets depicted an edge length in the 50–350 nm range with an observed thickness as low as 5 nm. The CuO-HS microsensor demonstrated ultrasensitivity (Rg/Ra = ∼85), dominant selectivity (>6 gases), repeatability (98.7%), CoV (1.3%), and LoD (4.3 ppm) at 32 °C towards CO2 in 20–5000 ppm. The role of structural defects in sensing was confirmed from operando UV-Vis-DRS & PL. Rapid dye degradation in natural sunlight shown by CuO-HS was primarily attributed to the lower charge reunification. Additionally, CuO-HS facilitated methanol formation within 3 h at a rate of 53 and 18 μmol g−1 in the presence of artificial solar and natural sunlight, respectively. Dye degradation and CO2 photoreduction pathways were probed using HPLC and GC-MS, respectively.

A porous 3D multifunctional Zn-MOF (1), namely {[Zn2.5(DDPP)(OH)(H2O)]•H2O•1.5DMF}n (H4DDPP = 3,5-di(2',5'-dicarboxylphenyl)pyridine, DMF = N,N-dimethylformamide) was solvothermally synthesized by the reaction of H4DDPP ligand and Zinc salts. 1 exhibits a high adsorption performance for N2 (246.2 cm3 g-1 at 77 K) and CO2 (116.1 cm3 g-1 at 273 K) as well as excellent selective separation for CO2/CH4 (V:V = 0.5:05) and CO2/CH4 (V:V = 0.05:0.95) with the selectivity coefficiens are 79.3 and 25.4 at 298 K and 1 bar, respectively. Meanwhile, 1 shows a great performance for H2O vapor sorption and the uptake amount of H2O vapor is 281.9 cm3 g-1 (at 298 K and P/P0 = 0.99), which is comparable to that reported in the literatures. Furthermore, 1 has excellent separation ability for H2O vapor in H2O/CH3OH mixed vapor and the selectivity of 1 for H2O/CH3OH (V:V = 0.1:0.9) and H2O/CH3OH (V:V = 0.05:0.95) is 254.6 and 94.9 at 298 K and 1 bar, repectively. More importantly, Grand Canonical Monte Carlo (GCMC) simulation shows that the reason for the good adsorption capacity of 1 for CO2 and H2O vapor is attributed to the pore structure of 1 and the interaction between the coordinated H2O molecules and μ3-OH- in 1 and CO2 or H2O molecule. In addition, 1 shows sensitive sensing ability for nitrofurantoin (NFT) and the detection limit (DL) was 5.3×10-8 M. Moreover, the fluorescence sensing mechanism of 1 for NFT can mainly be attributed to the competitive absorption between the absorption spectrum of NFT and the emission spectrum of 1, the weak interactions between μ3-OH- in 1 and NFT and photoinduced electron transfer from 1 to NFT.

Nanotechnology is a new area of research with new possibilities in various fields. Nanotechnology is a having the potential to take forward the agriculture with new tools which promises to increase food production and also protect the agriculture crops from pests, diseases etc. The present study focuses on the green synthesis of silver nanoparticles using plant extracts of Cassytha filiformis. Aqueous silver ions when exposed to plant leaf extract were reduced and resulted in a color change to dark brown indicating the formation of silver nanoparticles by using UV–Vis Spectroscopy which showed peak at in range from 400 nm to 480 nm which are characteristic peaks of silver nanoparticles. Synthesized silver nanoparticles were also characterized by other techniques such as Field Emission Scanning Electron Microscopy (FESEM) showed even shaped spherical nanoparticles with particle size of 42 nm. Energy Dispersive X-Ray (EDX) showed absorption peak approximately at 3 keV. Fourier Transform Infra Red (FTIR) showed chemical interactions of silver nanoparticles and Atomic force microscope (AFM) depicted the three dimensional structure of silver nanoparticle.

The green synthesis of nanoparticles using plant extracts plays an important role in the field of nanotechnology. The potential of biomolecules present in plant extracts in reducing metal ions to nanoparticles in a single step of green synthesis process is very important. In this study we report on synthesis of Chromium oxide nanoparticles (Cr2O3) by reduction of potassium chromate solution with Manihot esculenta leaf extract. The presence of water soluble carbohydrates which have an aldehyde group may lead the formation of Cr2O3 nanoparticles. The fabricated Chromium oxide nanoparticles were confirmed by UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM).XRD and UV–Visible absorption studies. The images showed that the size of NPs of Cr2O3 varied with average crystalline size 85–100 nm of nanosized Cr2O3.

Rechargeable batteries based on graphite are considered as promising alternatives for energy storage applications. The charge/discharge mechanisms of these batteries results from the intercalation and de-intercalation driven electrochemically by the atoms or molecules of the electrodes in contact with a liquid electrolyte. These solutions are often complex systems engineered to stabilize and allow the transport of the evolving moieties. In this article, we isolate the effect on the graphite structure of a chemical component of novel electrolytes, the aluminum fluoride (AlF3), by dosing this pure compound in the gas phase over high oriented pyrolitic graphite (HOPG) substrates at 10−9 mbar and 300 K. We performed an extensive experimental study involving surface characterization and beam analysis techniques, and developed a model of the sorption substantiated in ab-initio calculations. We found a preferential interlaminar absorption when dosing in the direction transversal to the carbon planes. The intercalation in the HOPG is spontaneous and non-reactive, and increases the interplanar spacing by 20%. A charge transfer of 0.65 e− per formula from graphite to AlF3 is calculated for the intercalate. Since the absorption depends on the roughness of the substrate we may infer that the intercalation proceeds through the step-edges. These features may contribute to the development of novel quasi-2D devices for special applications.

Copper oxide nanoparticle (NPs) was prepared by a green Chemistry approach. The synthesized NPs were characterized by XRD, SEM, FT-IR, and UV–Vis spectrophotometer. The XRD peaks matches with the standard X-ray diffraction patterns confirming monoclinic crystal phase. FT-IR absorption exhibits the existence of metal oxygen stretching bond at 422 cm−1. SEM study shows that the particles were highly porous in nature having irregular shape and are agglomerated. EDX spectrum confirms the presence of Cu and O in the synthesized NPs. The band gap was found to be 1.65 eV from UV– Vis studies. An enhanced photo degradation of Rose Bengal dye was indicated by synthesized NPs.

Efficient and reversible absorption of SO2 by deep eutectic solvents (DESs) has drawn much attention in recent years. In this work, a new type of deep eutectic solvents (DESs) were synthesized via pyridine derivatives, nicotinamide, aminopyridines and hydroxypyridines, as the hydrogen bond donors (HBDs) with common quaternary ammonium salt ionic liquids (ILs) as hydrogen bond acceptors (HBAs). The studied DESs exhibited an attractive absorption behavior for SO2, especially for low concentration SO2. The 1-allyl-3-methylimidazolium chloride (AmimCl)/2-aminopyridine (2-NH2Py) (2:1) and 1-butyl-3-methylimidazolium chloride (BmimCl)/3-aminopyridine (3-NH2Py) (2:1) could capture 0.273 and 0.223 g SO2/g DES at 293 K and 1.0 kPa, respectively, surpassing that of most DESs and ILs in the present literature. The influence of DES composition, temperature and pressure on SO2 absorption performance was systematically investigated. Moreover, the absorption mechanism studied by nuclear magnetic resonance (NMR) and Fourier transform infrared (FT-IR) spectroscopies indicated that the efficient absorption of SO2 was ascribed to the chemical interaction between the pyridine nitrogen atom and SO2.

The nano-/microstructured energetic materials (EMs) often display a unique combination of low-sensitivity and high-stability, but their structural control across multiple-length scales has proven difficult. Here, a polyvinyl pyrrolidone (PVP) polymer-directed crystallization method is developed to construct high explosive 1,3,5,7-Tetranitro-1,3,5,7-tetrazacyclooctane (HMX) polycrystalline aggregates with controllable molecular-scale structure (polymorph) and crystal-scale aggregation microstructures. It was found that the polymorph and microstructural characteristics of aggregates show a strong dependence on the initial supersaturation, PVP concentration and feeding rate. In particular, the morphology and the phase composition of the aggregates could be systematically tuned from δ-phase star-like aggregates to γ-phase flake spherulite by simply varying the HMX concentration. A slower feeding rate could lead to more compact spherulites with a well-defined Maltese-cross extinction pattern. According to the process analysis technology (PAT) and Hansen solubility parameters (HSPs) analysis, it was proposed that the preferential absorption of antisolvent and strong interaction between PVP/HMX could disrupt the local solution chemistry, lower the level of supersaturation and increase the induction time, resulting in regulation in the molecular assembly pathway of HMX. Moreover, the HMX spherulitic aggregates are much less sensitive to impact and friction than reported plate-like γ-HMX as well as raw HMX. This work provides a fresh way for the design and preparation of high explosive polycrystalline aggregates with well-defined multi-scale architectural features and reduced mechanical sensitivity.

Environmental benefits and amazing performance can be obtained by utilizing palm oil fibres and kenaf fibres which illustrate colossal potential in fibre reinforced composites. An investigation has been made to determine the effects of alkaline treatment on water absorption and swelling behaviour of palm oil fibre composites as well as kenaf fibre composites. Untreated and treated natural fibres and were prepared in random orientation with different volume fraction of palm oil fibres and kenaf fibres; 30%, 40%, and 60. All the treated fibres were treated with 1 w/v% and 5 w/v% of sodium hydroxide concentration. Water absorption test was performed by immersing the sample in the distilled water periodically measuring the sample weight. Thickness swelling test was carried out by measuring the thickness of the specimens before and after soaking in the distilled water within certain period of time. All specimens were observed under Scanning Electron Microscope (SEM) to study the fibre morphology. TPOF_30_5SH achieved the least percentage of water absorption (1.44%) when it was compared with the UPOF_30 and TPOF_40_1SH. UPOF_60 shows the highest percentage of thickness swelling (8.96%). TPOF_30_5SH and TPOF_40_5SH show reduction of water absorption when they were compared with UPOF_30 and UPOF_40 respectively. All the treated kenaf fibre composites with 5 w/v% sodium hydroxide concentration such as TKF_30_5SH, TKF_40_5SH and TKF_60_5SH show improved result of thickness swelling. Materials covering the surface of palm oil fibres and kenaf fibres were more effectively removed with 5 w/v% sodium hydroxide than by treatment with 1 w/v% sodium hydroxide while observing under SEM.

In the present work biogenic synthesis of silver nanoparticles using Cissus quadarangularis aqueous leaf extract and their evaluation of antimicrobial activities. The synthesized nanoparticles were confirmed by, X-ray diffraction (XRD), UV–visible absorption (UV–Vis), Scanning electron microscopy (SEM) and Fourier transform infra-red (FT-IR) spectroscopy. The surface plasmon resonance resulted in significant absorption at 450 nm. The XRD analysis confirmed the crystalline nature of the particles and average crystallite size was found to be 35 nm. Furthermore, FT-IR study was used to identify potential biomolecules involved in the bio reduction of silver ions. Bactericidal efficacy of synthesized nanoparticles against Gram-positive and Gram-negative bacteria was confirmed using an antimicrobial activity.

Ethylene phytic acid and unsaturated itaconic acid could be copolymerized in-situ and cross-linked on the cotton fabrics to enhance flame-retardant and crease-proofing properties. Natural phytic acid was modified with glycidyl meth-acrylate and characterized by IR, 1H NMR, and TG. The IR indicated that new characteristic absorption peaks appear near 1720 c/m, 1470 c/m, 1380 c/m, and 1002 c/m for the molar ratios phytic acid: glycidyl methacrylate of 1:3 or 1:6, the peaks correspond to the bending vibration of C=O, C?H, CH3, and C=O?O respectively in the glycidyl methacrylate. The 1H NMR results further confirmed the reaction between glycidyl methacrylate and phytic acid, and the TG results revealed the thermal properties of phytic acid.

In the present experimental investigation, green synthesis of nanostructured calcium ferrite (CaFe2O4) particles by solution combustion method and its application to photocatalytic degradation of evans blue dye. Physico-chemical properties of the synthesized nanoparticles (NPs) were elucidated by TEM, HRTEM, SAED, SEM, EDAX, BET, UV–Vis and FT-IR analyses. The spherical NPs undergo photocatalytic followed by adsorption. The NPs Dispersive reflectance spectrum shows bandgap value 1.92 eV and maximum absorption at 220 nm. HRTEM divulgence the space lattice 0.25 nm with an average particle size of 45 nm. The surface of the NPs SEM micrograph shows huge pores and voids which enhances the adsorption along with photocatalytic degradation. The CaFe2O4 NPs was optimized for the various photocatalytic followed adsorption parameters namely pH, the effect of dosage catalyst load, varying initial concentration of the dye. The maximum adsorption followed degradation capacity shows 42.42 mgg−1 (Nonlinear). The Sips model is the best-fitted isotherm equilibrium model with the least statistical errors and high correlation coefficient R2 0.988 (Nonlinear) compared to other models. The pseudo-second-order model shows the higher correlation coefficient R2 > 0.94 at all concentrations over other kinetic models. The Webber Morris model shows distinct linear phase shows Photocatalysis of degradation and adsorption follows a multistep mechanism. The study has shown it is possible to reuse the catalyst for adsorption and dye degradation with satisfactory efficiency for almost 5 cycles which indicates its photostability.

Lithium titanium oxide Li 4 Ti 5 O 12 (Li[Li 1 / 3 Ti 5 / 3 ]O 4 ) has been receiving significant attention as an ideal electrode material for lithium-ion batteries, because its cubic lattice parameter ( a c ) changes negligibly during the electrochemical reaction. However, this same characteristic hinders in-depth understanding of the reaction mechanism, restricting widespread applications, such as use in electric vehicles. We thus employed the recently developed operando X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) technique, combined with multivariate curve resolution by alternating least squares (MCR-ALS) method. The MCR-ALS analyses of both the XAS and XRD data confirmed a two-phase reaction scheme consisting of Li[Li 1 / 3 Ti 5 / 3 ]O 4 and Li 2 [Li 1 / 3 Ti 5 / 3 ]O 4 , but differences in the structural transformations clearly appeared at the two different scales. Linear, reversible changes in the bond distance between Ti and O atoms were observed at the atomic scale ( ∼ 1 nm), whereas hysteresis in a c between the discharge and charge reactions was observed at the microscale ( ∼ 100 nm). This difference was found to originate from the difference in spatial resolutions between the XAS and XRD techniques.

Previously we had developed a microfluidic system that can be easily fabricated by bending a stainless-steel tube into large circular loops. In this study, a fast and continuous preparation method for superfine TiO2 nanoparticles (TiO2-NPs) was developed for the aforementioned microfluidic system. The proposed method can yield anatase TiO2 in 3.5 min, in contrast to the traditional hydrothermal reaction method, which requires hours or even days. Different reaction conditions, such as reaction temperature (120–200 °C), urea concentration (20–100 g/L), and tube length (5–20 m) were investigated. X-ray diffraction and Brunauer–Emmett–Teller analysis indicate that the as-prepared TiO2-NPs have crystalline sizes of 4.1–5.8 nm and specific surface areas of 250.7–330.7 m2/g. Transmission electron microscopy images show that these TiO2-NPs have an even diameter of approximately 5 nm. Moreover, because of their small crystalline sizes and large specific surface areas, most of these as-prepared TiO2-NPs exhibit considerably better absorption and photocatalytic performance with methylene blue than commercial P5 TiO2 does.

The SO2 absorption/desorption performances of 14 aqueous amino acid solutions were evaluated to identify efficient absorbents to remove SO2 from coal-powered plant emissions. SO2 absorption/desorption experiments were conducted at 298.15 and 373.15 K, respectively, using 600 ppmv SO2 (N2 balance) and N2 purging. Thereafter, the absorption/desorption loadings and rates of the solutions, as well as their net cyclic capacities, were compared. The SO2 absorption mechanisms were explored via 13C NMR, 1H NMR, and UV–Vis analyses, and the relationship between the pKa values and absorption performances of the 14 aqueous amino acid solutions was investigated. Furthermore, the effects of absorption temperature, absorbent concentration, and inlet SO2 concentration on the SO2 absorption performances of the solutions were explored. 5-Aminovaleric acid, 4-aminobutyric acid, β-alanine, and histidine were identified as suitable SO2 absorbents based on their absorption/desorption performances and their net cyclic capacities. Furthermore, the net cyclic capacities of these four absorbents were similar or superior to those of previously reported deep eutectic solvents and ionic liquids. The results of this study provide a strategy for preparing eco-friendly SO2 absorbents.

The selective separation of soluble and individual single-walled carbon nanotubes (SWCNTs) in aqueous solution is a key step for harnessing the extraordinary properties of these materials. Manipulating the strong van der Waals intertube interactions between the SWCNT bundles is very important in selective separation, which is a long-standing challenge. Here we reported the ability of redox polyoxometalate clusters to modulate the intertube π-π stacking interaction through electron transfer and achieved the diameter-selective separation of SWCNTs in a surfactant aqueous solution. The large-diameter SWCNTs concentrated at ∼1.3-1.4 nm were selectively separated when ∼1 nm clusters encapsulated within the tube cavity, and the dispersion of subnanometer ∼0.7-0.9 nm SWCNTs was boosted when clusters were adsorbed on the outer surface of small-diameter nanotubes. The mechanism of diameter-selective separation of SWCNTs associated with the size-dependent interaction between cluster-tubes and the steric hindrance effect of clusters was revealed by optical absorption and Raman spectroscopy. This simple method thus enables the selective separation of individual high-quality SWCNTs in aqueous solutions without harsh sonication with the potential for other separation applications.

The oxygen evolution reaction (OER) is the bottleneck reaction of water splitting, which can be used to generate green hydrogen from renewable electricity. Cobalt iron oxyhydroxides (CoFeOxHy) are among the most active OER catalysts in alkaline medium. However, the active sites of these catalysts remain unclear. Here we use operando ultraviolet-visible (UV-Vis), X-ray absorption, and Raman spectroscopy to reveal oxidations of both Fe and Co ions in CoFeOxHy during the OER. By analyzing samples with different Fe contents and thickness, we find that the concentration of Fe4+ species at the surface, but not the concentration of Co4+ in the bulk, scales with the catalytic activity. These results indicate an Fe4+-containing active site in CoFeOxHy.

Existence of a very lesser quantity of dyes in water, which are still highly visible, extremely affects the quality and clearness of water bodies such as lakes, rivers, ponds and others water bodies, leading to harm to the aquatic environment. So it is significant to eliminate the harmful dyes which are very hazardous to the living organisms. Treatment of wastewater is challenging because dyes are water soluble so its removal becomes tough. In this work synthetic copolymer adsorbent of AA and AMP was successfully synthesized at many compositions. All the characteristic absorption bands of PAA and PAMP are observed by FTIR analysis, which indicates the successful copolymerization of AA and AMP. Adsorption experiments were accomplished at different contact time, adsorbent dose, pH conditions and temperature. 0.1 g dose of copolymer adsorbent has been found to be optimum for adsorption study. The kinetic study of adsorption was also investigated using pseudo first order kinetic model. From the study, it was establish that the prepared copolymer adsorbent was proficient to eliminate crystal violet dye at various temperature and time. Maximum 98% of crystal violet dye removal was achieved at high pH around 10. A maximum adsorption capacity of 9.8 mg/g was obtained for copolymer adsorbent of 1:1 ratio. Copolymer adsorbent (AA-AMP) provide a novel and effective type of adsorbents to remove CV dye from the aqueous solution.

The interface between Mg alloy and the intermetallic compounds (IMCs) is the weak point during the welding of Mg alloy and steel. The models of AlNi surface under different number of absorbed magnesium atoms were established. The absorption energy and electronic properties of the Nth (N represents the number of Mg atoms, which may be 1, 2, 3, and 4 in this paper) Mg atom on the AlNi surface were calculated using first-principles calculations. The results show that the previously absorbed Mg atoms will promote the absorption of the latter Mg atom when the distance between them is equal or less than 2.89 A. The absorption energy of the Mg atoms on the AlNi surface is related to the electronic exchange between different atoms. The results will provide a new perspective for understanding the atomic scale mechanism of the bonding between the Mg atom and AlNi IMCs.

Irradiation embrittlement is one of the most important phenomena in the structural integrity assessment for long-term operated reactor pressure vessels (RPVs). The causes of the irradiation embrittlement of RPVs are the formation of solute clusters and matrix defects. To investigate these embrittlement mechanisms, it is necessary to complementarily apply multiple microstructure analyses such as atom probe tomography and transmission electron microscopy. The extended X-ray absorption fine structure (EXAFS) technique can detect changes in the atomic structure by irradiation around selected atoms. In this study, we performed an EXAFS examination for RPV steels subjected to ion irradiation. We investigated microstructures of the crystal structure around specific element such as Cu, Mn, and Ni. The results indicated that the solute atoms cluster is thought to aggregate in the Fe matrix while maintaining the body-centered cubic structure and that a dumbbell pair could be located around both Cu and Ni atoms.

In the present work, a polyphenylene oxide/Polyvinyl pyrrolidone (PPO/PVP) thin film has been synthesized by using a spin coating technique. The structural and optical properties of the thin film were studied by using X-ray diffraction and optical absorption spectroscopic techniques. The XRD results showed that precursor polymers PPO and PVP along with PPO/PVP-based polymer film exhibited amorphous behavior. Optical properties were obtained using UV–Vis spectroscopy. Two absorption peaks were identified in the UV area, at 311 nm and 367 nm, respectively, and the optical band gap of the PPO/PVP film was found at 2.9 eV. The synthesized PPO/PVP thin film had an Urbach energy of 0.294 eV, as per the findings.

The ability to tune the structural properties with respect to the size, polarity, and terminal functionalities makes dendrimers a highly attractive class of compounds with potential biological and catalytic applications. In the present study, Janus (J) and Twin (T) benzamide-based branched structures were synthesized from a primary precursor of methyl gallate and then further characterized using spectroscopic and theoretical techniques. The optimized structures of these dendrimer precursors at the B3LYP/6-311G(d) level revealed that the aliphatic chains in the most stable forms are oriented in the least strained arrangement with the (−benzene−O−CH2−) linkage adopting the phenol-like configuration. The UV-Vis spectra showed a consistent absorption nearly at 290 nm, suggesting that both molecules absorb within the ultraviolet region and are colorless. Prominent bands which include the -OH vibrational stretch, the -C=C- stretch, the -C=O stretch, the -C-O in-plane stretch, and the -NH in-plane bending were assigned and correlated with structural and electronic aspects of the molecules.

The potential newly contrived, synthesized and attested rhodamine derivative for colorimetric detection of Zn2+ and fluorimetric detection of Sn4+. The action of probe with these two metals results in commutation of optical property which has been ascertained to be sensitive, selective and hardly influenced by other metal ions. The Zn2+ induced absorption changes whereas the Sn4+ induced emission changes with the probe. This dual sensing effective probe can be used for detection of these two physiologically/environmentally important metal ions by dual mode detection i.e. Zn2+ by UV–Vis spectroscopy and Sn4+ by and fluorescence spectroscopy.

Separation of oil/water mixtures using monolithic porous materials is an attractive approach for absorbing a variety of polar and apolar solvents from their mixtures. In our work, we report a simple and low-cost fabrication of macroporous monolith followed by hydrophobization with adsorption of candle soot particles (CSPs). This modification makes it omniphilic and substantially enhance its hydrophobic nature by packing of CSPs into the polymeric walls of the monolith as confirmed by scanning electron micrographs. Water contact angle (WCA) and solvent absorption behaviour of CSP-adsorbed monoliths were studied and subsequently, were employed for the separation of floating oil/water mixture. Unmodified monolith S0 is hydrophilic in nature and absorbs over 30 times its weight when dipped in water. WCA study reveals that the contact angle increases systematically from 0 to ∼ 130° with an increase in CSP concentration and monolith S5 can absorb chloroform more than 38 times its weight. Monoliths possess high mechanical strength and can be used for repetitive compression/absorption cycle for solvent absorption. These high porosity sponges provide an effective strategy, high-performance controllable absorbability, and can be used as a separation tool for floating oil/water mixtures.

Structural elucidation of small molecules only available in low quantity (nanogram) is one of the big advantages of the crystalline sponge method. The optimization of various soaking parameters is crucial for effective analyte absorption and repetitive positioning in the pores of the crystal. Time-consuming X-ray diffraction measurements are necessary for data collection and confirmation of successful guest inclusion. In this work, we report a screening method to select optimal soaking conditions without the need of single-crystal X-ray diffraction analysis for individual compounds and mixtures. 14 substances were chosen as test compounds. Parallel guest soaking of individual compounds and mixtures was conducted using various soaking conditions. After evaporation of solvent, excessive material was removed, and guest molecules released through dissolution of the framework. Liquid chromatography-tandem mass spectrometry allowed the estimation of analyte trapped in the pores and the selection of optimal soaking condition dependent on the highest amount of analyte to crystal size (affinity factor). The tool allowed subsequent crystallographic analysis of ten compounds with minimal experiment time. Additionally, a study to examine the lower limit of detection of the crystalline sponge method was conducted. Determination of two target analytes was possible using only 5 ng of sample. Our study shows the potential of an affinity screening to prioritize soaking parameters by estimation of the guest concentration in a single crystal for one or multiple target compounds within a short period of time.

On the basis of the higher order perturbation formulas of g-factors for a 4d1 group in tetragonally compressed octahedra, the g-factors, optical absorption, local structure and their concentration dependences of pentavalent molybdenum in 40PbO-(10-x)Y2 O3 -50P2 O5 :xMoO3 (1 ≤ x ≤ 5 mol%) glass are uniformly investigated. The experimental optical absorption spectra and g factors for Mo5+ at various concentrations x are reasonably regenerated by using the reasonable exponential concentration functions of the cubic field parameter Dq, covalent factor N and relative tetragonal compression ratio ρ. The tetragonal compression ratio ρ due to the Jahn-Teller effect was found in the range of 3.8-4.2%. The decreasing trend of Dq and N and the increasing trend of ρ with concentration can be interpreted as the fact that the variations of MoO3 and Y2 O3 concentrations lead to the modulations of local structure and electron cloud distribution around Mo5+ , associated with the adjustment of the glass network. The concentration dependence of optical basicity is also analyzed for the above glass systems.

The amino-functionalized cage-opened [60]fullerene derivatives were synthesized by reactions with phenylenediamine. In this reaction, the diamine undergoes direct addition to the α,β-unsaturated carbonyl moiety. Further C-C bond scission is promoted by the intramolecular SN2 reaction. These amino-functionalized derivatives possess high-lying highest occupied molecular orbital levels as suggested by electrochemical analyses. These compounds showed intense near-infrared absorption bands that tail to 900 nm, reflecting the optical transition with π-π* and charge transfer character.

Mercury (Hg) ions can lead to a serious impact on the environment; therefore, it was necessary to find an effective method for absorbing these toxic Hg ions. Here, the adsorbent (Zn-AHMT) was synthesized from zinc nitrate and 4-amino-3-hydrazine-5-mercapto-1,2, 4-triazole (AHMT) by one-step method and, characterized the microstructure and absorption performance by fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Thermal Gravimetric Analyzer (TGA) and X-ray photoelectron spectroscopy (XPS). Through a plethora of measurements, we found that the maximum adsorption capacity was 802.8 ​mg/g when the optimal pH of Zn-AHMT was 3.0. The isothermal and kinetic experiments confirm that the reaction process of Zn-AHMT was chemisorption, while the adsorption process conforms to the Hill model and pseudo second order kinetic model. Thermodynamic experiments showed that the adsorption process was spontaneous and exothermic. Selective experiments were performed in the simulated wastewater containing Mn, Mg, Cr, Al, Co, Ni, Hg ions. Our results showed that the Zn-AHMT has a stronger affinity for Hg ions. The removal rate of Zn-AHMT remained above 98%, indicating that the Zn-AHMT had a good stability validated by three adsorption-desorption repeatable tests. According to the XPS results, the adsorption reaction of Zn-AHMT was mainly attributed to the chelation and ion exchange. This was further explained by both density functional theory (DFT) calculation and frontier molecular orbital theory. We therefore propose the adsorption mechanism of Zn-AHMT. The adsorption reaction facilitates via the synergistic action of S and N atoms. Moreover, the bonding between the adsorbent and the N atom has been proved to be more stable. Our study demonstrated that Zn-AHMT had a promising application prospect in mercury removal.

Novel green and blue chromophores based on Ni/Co/Cr doped BaMg6Ti6O19 solid solutions are successfully synthesized through a solid-state reaction. The crystal structure of all the samples belongs to the magnetoplumbite structure with the space group of P63/mmc. The BaMg6-x/2Ti6-x/2NixO19 (0 ≤ x ≤ 0.3) compounds exhibit a light green (x = 0.1) to yellow-green (x = 0.3) color. The oxidation state of Ni is confirmed to be +2 valence and the d-d transition of Ni2+ in octahedral sites is responsible for color. BaMg6-x/2Ti6-x/2CoxO19 (0 ≤ x ≤ 0.3) series show a blue color and the intensity of blueness is increasing with the increase of Co content. The blue color is due to d-d transitions within Co2+ present in the tetrahedral sites. For BaMg6-x/2Ti6-x/2CrxO19 (0 ≤ x ≤ 2) phases the color varies from light green (x = 0.2) to green (x = 2). Chromium exists in +3 and + 6 oxidation states and the observed color is due to charge transfer transition between Cr3+–Ti4+ and d-d transitions within octahedral Cr3+ sites resulting in strong absorption in the visible region. The synthesized colored oxides are mixed with PMMA to prepare novel green and blue PMMA polymer composites to evaluate their compatibility in plastics.

Effective and reversible absorption of sulfur dioxide (SO2) with commercially available and easily prepared absorbents now has drawn increasing concentration. In this work, a series of amine-based ...