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The specific structure and diverse properties of hybrid organic-inorganic perovskite materials make them suitable for use in photovoltaic and sensing fields. In this study, environmentally stable organic-inorganic hybrid perovskite luminescent materials using Pb-MOF as a particular lead source were prepared using a mechanochemical method. Based on the fluorescence intensity of the MAPbBr3/MOF composite, the mechanized chemical preparation conditions of Pb-MOF were optimized using response surface methodology. Then, the morphological characteristics of the MAPbBr3/MOF composite at different stages were analyzed using electron microscopy to explore its transformation and growth process. Furthermore, the composite form of MAPbBr3 with Pb-MOF was studied using XRD and XPS, and the approximate content of MAPbBr3 in the composite material was calculated. Benefiting from the increase in reaction sites generated from the crush of Pb-MOF during mechanical grinding, more MAPbBr3 was generated with a particle size of approximately 5.2 nm, although the morphology of the composite was significantly different from the initial Pb-MOF. Optimal performance of MAPbBr3/MOF was obtained from Pb-MOF prepared under solvent-free conditions, with a milling time of 30 min, milling frequency of 30 Hz and ball-material of 35:1. It was also confirmed that the mechanochemical method had a good universality in preparing organic-inorganic hybrid perovskite/MOF composites.

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A mechanochemical approach was utilized to prepare modified kaolin, and the hydrophobic modification of kaolin was realized. The study aims to investigate the changes in particle size, specific surface area, dispersion ability, and adsorption performance of kaolin. The structure of kaolin was analyzed using infrared spectroscopy, scanning electron microscopy, and X-ray diffraction, and the alterations to the kaolin microstructure were thoroughly researched and discussed. The results demonstrated that this modification method can effectively improve the dispersion and adsorption capacities of kaolin. Mechanochemical modification can increase the specific surface area of kaolin particles, reduce their particle size, and improve their agglomeration behavior. The layered structure of the kaolin was partially destroyed, the degree of order was debased, and the activity of its particles was enhanced. Furthermore, organic compounds were adsorbed on the surface of the particles. The appearance of new infrared peaks in the modified kaolin's infrared spectrum suggested that the kaolin has undergone a chemical modification process, introducing new functional groups.

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A mechanochemical (MC) method was employed for the remediation of soil contaminated with fluoranthene (C16H10, FL) a four-ringed polycyclic aromatic hydrocarbon (PAH) containing three benzene rings and a central five-membered heterocyclic ring, with the effects of soil inorganic components, milling conditions, and the degradation mechanism investigated. Results showed that the addition of SiO2 and kaolin to soil resulted in a greater increase in the effectiveness of FL removal than other inorganic additives. After 3 hours of milling at 500 rpm, the FL removal rate from SiO2 containing soil, reached 99.26%, with the removal efficiency increasing in accordance with an increase in milling duration and speed. The milled samples were characterized by FT-IR, Raman spectroscopy, and GC-MS analysis, revealing the mechanism of FL degradation, including destruction of the aromatic skeleton structure and the formation of amorphous carbon and graphite. The MC remediation method was applied to FL contaminated soil, showing that FL was efficiently degraded in soil without any soil additives, resulting in a significant reduction in the biotoxicity of the remediated soil. The organic matter, moisture content and pH of the actual soil changed slightly after mechanical ball milling. Thus, the MC method has high potential in the remediation of PAH-contaminated soils.HIGHLIGHTSA mechanochemical (MC) method for the degradation of fluoranthene was assessed.The use of silica and kaolin as soil additives enhances fluoranthene remediation.Fluoranthene can be efficiently removed from contaminated soil by milling alone.The degradation mechanism was skeleton structure destruction and carbonization.The biotoxicity of soil was significantly reduced by milling.

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A recycling process of waste thermosetting polyurethane plastics was proposed based on the mechanochemical method, aiming at the three-dimensional network cross-linking structure of thermosetting polyurethane. Orthogonal experimental design was adopted to select three factors of crushing speed, crushing time, and feed amount to determine the best crushing parameters. Then, the waste polyurethane insulation boards were crushed and degraded by the mechanism of regenerative forming with the adjustable speed test machine. Accordingly, the recycled powder was obtained. Finally, nine kinds of polyurethane recycled composite plates were prepared by hot pressing process. The degradation effect of thermosetting polyurethane was analyzed by Fourier transform infrared spectroscopy, scanning electron microscope, and X-ray diffraction. Moreover, the mechanical properties and thermal insulation properties of recycled composite plates were tested and analyzed. The results show that the network cross-linking molecular structure of waste thermosetting polyurethane plastics is destroyed by the effect of mechanochemical action, and methyl and aldehyde groups are decomposed. Therefore, a recycled powder with strong reactivity and plasticity is generated, which improves the activity regeneration ability. After adding thermoplastic resin, the mechanical properties and formability of recycled composite plates are enhanced, with maximum tensile strength up to 9.913 MPa. Correspondingly, the thermal insulation performance of plates is reduced. However, the minimum thermal conductivity can also reach 0.056 W/m·K. This study provides an effective method for the recycling of thermosetting polyurethane plastics.

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A large number of waste tires are in urgent need of effective treatment, and breaking waste tires into crumb rubber powder for modifying asphalt has been proved as a good idea to solve waste tires. Crumb rubber modified asphalt not only has good high and low temperature performance, durability, and aging resistance but can also reduce pavement noise and diseases, which has wide application prospects. In this study, crumb rubber powder was desulfurized by mechanochemical method to prepare desulfurized crumb rubber modified asphalt. During the desulfurization process of crumb rubber, the effects of desulfurization process variables including desulfurizer type, desulfurizer content, and desulfurization mixing temperature and time were considered, and then the physical properties of modified asphalt were tested. The test results showed that after mixing crumb rubber powder with desulfurizer, the viscosity of crumb rubber powder modified asphalt can be reduced. Moreover, the storage stability of crumb rubber powder modified asphalt could also be improved by mixing crumb rubber with desulfurizer. Based on the physical properties of crumb rubber powder modified asphalt, the desulfurization process of selected organic disulfide (OD) desulfurizer was optimized as follows: the OD desulfurizer content was 3%, the desulfurization mixing temperature was 160 °C, and the mixing time was 30 min. In addition, Fourier infrared spectroscopy analysis was carried out to explore the modification mechanism of desulfurized crumb rubber powder modified asphalt. There is no fracture and formation of chemical bonds, and the modification of asphalt by crumb rubber powder is mainly physical modification.

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In the present study, we adopt an easy and cost-effective route for preparing Cu2ZnSnS4 (CZTS)-absorber nanoparticles by a mechanochemical method using non-toxic and environmentally benign solvents (butanol, methyl ethyl ketone, and ethanol). The gram-scale synthesis of absorber nanoparticles was achieved in a non-hazardous, zero-waste process without using high-vacuum equipment. The effects of annealing and Na incorporation on the properties of spin-coated CZTS thin films were scrutinized. The deposited samples showed kesterite crystal structure and single phase. The morphological results revealed an improvement in the surface morphology after annealing. The optical bandgaps of the thin films lied in the range of 1.50-1.57 eV with p-type nature. Finally, photovoltaic devices were fabricated, and their cell performance parameters were studied. An efficiency of 0.16% was observed. The present study provides a potential route for the cost-effective fabrication of CZTS-based photovoltaic devices.

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This study used a mechanochemical method to analyze the recycling mechanism of polyurethane foam and optimize the recycling process. The use of mechanochemical methods to regenerate the polyurethane foam powder breaks the C-O bond of the polyurethane foam and greatly enhances the activity of the powder. Based on orthogonal test design, the mesh, proportion, temperature, and time were selected to produce nine recycled boards by heat pressing. Then, the influence of four factors on the thermal conductivity and tensile strength of the recycled board was analyzed. The results show that 120 mesh polyurethane foam powder has strong activity, and the tensile strength can reach 9.913 Mpa when it is formed at 205 °C and 40 min with 50% PP powder. With the help of the low thermal conductivity of the polyurethane foam, the thermal conductivity of the recycled board can reach 0.037 W/m·K at the parameter of 40 mesh, 80%, 185 °C, 30 min. This research provides an effective method for the recycling of polyurethane foam.

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The traditional methods for preparing magnesium aluminum layered double hydrotalcite (Mg2Al-CO3LDHs) in industry include coprecipitation and hydrothermal methods. Both these methods have the disadvantages of high preparation cost and complicated water washing process. Using Mg(OH)2, Al(OH)3, and CO2 as raw materials in this work, the Mg2Al-CO3 LDHs are successfully prepared by mechanochemical method, which solves the shortcomings of traditional preparation method and realizes the conversion and utilization of CO2 resource. The prepared Mg2Al-CO3 LDHs are evaluated as a heat stabilizer in poly(vinyl chloride) (PVC). The result indicates that, when 2.4 phr Mg2Al-CO3 LDHs, 0.3 phr ZnSt2, and 0.3 phr of zinc acetylacetonate are added to the PVC, the thermal stability time of PVC can reach 190 min, which is better than PVC containing commercial Mg2Al-CO3 LDHs. Meanwhile, its processing performance is basically the same as the PVC containing commercial Mg2Al-CO3 LDHs.

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In this paper, ultra-small CuO nanoparticles (NPs) were synthesized through a mechanochemical method using two different Cu-containing precursors (i.e. CuSO4·5H2O and CuCl2·2H2O), and their structure and antibacterial activity were studied. From the microstructural studies, it was observed that CuO NPs have a spherical morphology and a narrow size distribution with 7 and 14 nm median particle sizes for CuCl2·2H2O and CuSO4.5H2O precursors, respectively. The CuCl2·2H2O derived nanoparticles showed more antibacterial activity than CuSO4.5H2O derived nanoparticles. The minimum inhibitory concentration (MIC) of the synthesized nanoparticles (derived from both precursors) against E. coli and S.aureus were 3.75 and 2.50 mg/ml, respectively, which are higher than those reported in the literature for CuO NPs synthesized by other methods. This difference may be originated from ultra-small size of the synthesized nanoparticles, high bandgap energy and Fe inclusion entering from milling media and their effect on oxidative stress-mediated cytotoxicity of CuO NPs. The higher MIC value reported in this work indicates that the synthesized NPs not only show good antibacterial activity, but also they yield lower cytotoxicity, which extends their applications in the biomedical field.

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The study presented in this work consists of two parts: The first part is the synthesis of Graphene oxide-Fe3O4 nanocomposites by a mechanochemical method which, is a mechanical process that is likely to yield extremely heterogeneous particles. The second part includes a study on the efficacy of these Graphene oxide-Fe3O4 nanocomposites to kill cancerous cells. Iron powder, ball milled along with graphene oxide in a toluene medium, underwent a controlled oxidation process. Different phases of GO-Fe3O4 nanocomposites were obtained based on the composition used for milling. As synthesized nanocomposites were characterized by x-ray diffraction (XRD), alternating magnetic field (AFM), Raman spectroscopy, and a vibrating sample magnetometer (VSM). Additionally, the magnetic properties required to obtain high SAR values (Specific Absorption Rate-Power absorbed per unit mass of the magnetic nanocomposite in the presence of an applied magnetic field) for the composite were optimized by varying the milling time. Nanocomposites milled for different extents of time have shown differential behavior for magneto thermic heating. The magnetic composites synthesized by the ball milled method were able to retain the functional groups of graphene oxide. The efficacy of the magnetic nanocomposites for killing of cancerous cells is studied in vitro using HeLa cells in the presence of an AC (Alternating Current) magnetic field. The morphology of the HeLa cells subjected to 10 min of AC magnetic field changed considerably, indicating the death of the cells.

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γ-Graphyne is a new nanostructured carbon material with large theoretical Li+ storage due to its unique large conjugate rings, which makes it a potential anode for high-capacity lithium-ion batteries (LIBs). In this work, γ-graphyne-based high-capacity LIBs are demonstrated experimentally. γ-Graphyne is synthesized through mechanochemical and calcination processes by using CaC2 and C6 Br6 . Brunauer-Emmett-Teller, atomic force microscopy, X-ray photoelectron spectroscopy, solid-state 13 C NMR and Raman spectra are conducted to confirm its morphology and chemical structure. The sample presents 2D mesoporous structure and is exactly composed of sp and sp2 -hybridized carbon atoms as the γ-graphyne structure. The electrode shows high Li+ storage (1104.5 mAh g-1 at 100 mA g-1 ) and rate capability (435.1 mAh g-1 at 5 A g-1 ). The capacity retention can be up to 948.6 (200 mA g-1 for 350 cycles) and 730.4 mAh g-1 (1 A g-1 for 600 cycles), respectively. These excellent electrochemical performances are ascribed to the mesoporous architecture, large conjugate rings, enlarged interplanar distance, and high structural integrity for fast Li+ diffusion and improved cycling stability in γ-graphyne. This work provides an environmentally benign and cost-effective mechanochemical method to synthesize γ-graphyne and demonstrates its superior Li+ storage experimentally.

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BACKGROUND: Pharmaceutical co-crystals are the homogeneous crystalline substances composed of two or more substances bound together in the same crystal lattice via noncovalent interactions like hydrogenbonding, electrostatic interaction and Vander Waals interactions. Currently, co-crystals provide excellent opportunities to the formulation scientists in developing new pharmaceutical products by improving the pharmaceutically significant properties like solubility, dissolution rate, bioavailability, stability, and some other derived properties. Due to their ability to improve pharmacokinetic performance and their important intellectual property status, co-crystals are likely to have a very significant role in future drug development. Thus, formulation scientists have their focus on the development aspects of a co-crystallization process that include a rational selection of co-former, the discovery of novel synthetic procedures and new characterization techniques, and large scale production of these novel materials. OBJECTIVE: The objective of this article is to present an extensive review of solvent-free methods for co-crystal synthesis, mainly focusing on the principle mechanisms, advantages, and drawbacks of each method. CONCLUSION: From the review of the topic, it is clear that the solvent-free methods can offer numerous advantages over solvent-based methods in the design and the production of co-crystals of pharmaceutical use and these methodologies can also pave the path to advancing the field of co-crystal synthesis. Some of the advantages accompanied with solvent-free methods are the use of no or very less amount of solvent(s), exceptional purity and quality of produced co-crystal, large scale production and the short reaction times in few cases.

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Τhe photocatalytic activity in the range of visible light wavelengths and the thermal stability of the structure were significantly enhanced in Si, N co-doped nano-sized TiO2, and synthesized through high-energy mechanical milling of TiO2 and SiO2 powders, which was followed by calcination at 600 °C in an ammonia atmosphere. High-energy mechanical milling had a pronounced effect on the mixing and the reaction between the starting powders and greatly favored the transformation of the resultant powder mixture into an amorphous phase that contained a large number of evenly-dispersed nanocrystalline TiO2 particles as anatase seeds. The experimental results suggest that the elements were homogeneously dispersed at an atomic level in this amorphous phase. After calcination, most of the amorphous phase was crystallized, which resulted in a unique nano-sized crystalline-core/disordered-shell morphology. This novel experimental process is simple, template-free, and provides features of high reproducibility in large-scale industrial production.

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In the present study, cathode materials (C/LiCoO2) of spent lithium-ion batteries (LIBs) and waste polyvinyl chloride (PVC) were co-processed via an innovative mechanochemical method, i.e. LiCoO2/PVC/Fe was co-grinded followed by water-leaching. This procedure generated recoverable LiCl from Li by the dechlorination of PVC and also generated magnetic CoFe4O6 from Co. The effects of different additives (e.g. alkali metals, non-metal oxides, and zero-valent metals) on (i) the conversion rates of Li and Co and (ii) the dechlorination rate of PVC were investigated, and the reaction mechanisms were explored. It was found that the chlorine atoms in PVC were mechanochemically transformed into chloride ions that bound to the Li in LiCoO2 to form LiCl. This resulted in reorganization of the Co and Fe crystals to form the magnetic material CoFe4O6. This study provides a more environmentally-friendly, economical, and straightforward approach for the recycling of spent LIBs and waste PVC compared to traditional processes.

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The combination of mechanochemical method and thermal desorption for remediating polychlorinated biphenyls (PCBs) in contaminated soil was tested in this study. The effects of grinding time and heating time on PCB removal efficiency were investigated. The contaminated soil, mixed with CaO powder at a weight ratio of 1:1, was first ground using a planetary ball mill. After 4 h of grinding, the total PCB concentration and its toxic equivalence quantity (TEQ) decreased by 74.6 and 75.8%, respectively. Then, after being heated at 500 °C for 60 min, the residual PCBs in mechanochemical + thermal treated soil decreased to 247 ng/g, resulting in a removal efficiency of 99.95%. The removal effect can be promoted by longer grinding time and heating time; however, increased energy consumption was inevitable. The combination of grinding time and heating time should be optimized in a practical remediation process.

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Hydroxyapatite (HA) nanoparticles were synthesized using a wet mechanochemical method without a calcination process. Dicalcium phosphate dihydrate (CaHPO4 ·2H2 O) and calcium carbonate (CaCO3 ) were mixed and milled in a planary mill using ethanol or water as liquid media in the two different synthesized routes. Effects of rotation speed and milling time on the final products formed have been studied. Experimental results showed that HA phase having a characteristic of low crystallinity could be formed under the synthesis route using water. The original phases of both starting chemicals were remained without HA formation in the synthesis route using ethanol. Particle size and morphology of HA nanoparticles were obviously depended on optimum conditions of rotation speed and milling time. Differences on phase formation in both synthesized routes have been considered and discussed based on occurring chemical reaction possibilities. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 679-688, 2017.

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The Co3O4/CuO composite nanopowder (NP) was synthesized by a mechanochemical method and characterized by using powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The synthesized Co3O4/CuO NP was used as a modified carbon paste electrode (MCPE) and further the bare carbon paste and Co3O4/CuO NP modified carbon paste was heated at different temperatures (100, 150, 200 and 250 °C) for 10 min. The Co3O4/CuO NP MCPE was used to study the consequences of scan rate and dopamine concentration. Furthermore the preheated modified electrodes were used to study the electrochemical response to dopamine (DA), ascorbic acid (AA) and uric acid (UA).

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