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Functional fillers can facilitate the development of novel composite paper products for specific end uses. But using functional components as fillers by direct addition to the fiber suspension may fall short of the desired goals. The functional filler may fail to be efficiently retained. Gels can serve as carriers of functional paper fillers by coupling with them during in-situ synthesis and the gelation process. This strategy is favorable for the effective utilization of functional paper fillers, without hampering the intrinsic properties of paper. Additional merits of this strategy include versatility and compatibility with existing paper-making processes.

The in-situ synthesis of calcium silicate in the fiber can not only meet the requirements for high loading of paper, but also make up and improve the reduction of paper performance caused by filling. In this investigation, the effects of pulp type, beating degree, fiber ratio, reaction time, rotational speed, dosage of lime milk and dispersant on calcium silicate loading and paper properties were investigated. The results showed that when the beating degree was 40 °SR, the ratio of softwood and hardwood pulp was 1:1, the reaction time was 60 min, the rotation speed was 600 r·min−1, the dosage of lime milk was 1.33 times of the theoretical amount, and the dosage of cationic polyacrylamide was 0.3 % (absolutely dry pulp), the ash content of hand-made sheet was 41.2 %, and the loading amount of calcium silicate was 26.3 %. Under this condition, the comprehensive performance of paper was the best. [ABSTRACT FROM AUTHOR]

Abstract Surface enhanced Raman scattering (SERS) substrates that can be attached to rough, irregular surfaces and directly collect samples is especially useful for the detection of surface organic residues. Herein, novel AuNPs-pseudo-paper films (APPFs) with uniform structure, flexible properties and wicking capabilities were first fabricated and used as SERS substrate for the sensitive detection of surface pesticides residues. Gold nanoparticles (AuNPs) were in situ synthesized on pseudo-paper films (PPFs) by iterative seeding method to create lots of "hot-spots", accordingly exhibiting high SERS activity (SERS enhancement factor of 3.02 × 106). By virtue of polyethylenimine (PEI) grafted onto the dissolved microcrystalline cellulose (MCC), AuCl 4 - and AuNPs can firmly be bonded to the surfaces of PPFs. The prepared APPFs show high reproducibility (relative standard deviation of 6.13%), which is attributed to the uniform surface of the films. The fabricated APPFs SERS substrate allows rapid detection of surface pesticides residues by a facile "swabbing-measure" detection mode avoiding tedious and time-consuming sampling and separation processes. Based on their inherent SERS spectra, thiram, parathion methyl, and malachite green (MG) can be simultaneously detected on apple peel, which demonstrates the potential applicability of this developed protocol for surface organic residues analysis in agriculture and food security. Graphical abstract fx1 Highlights • APPFs SERS substrate with uniform structure, flexible properties and wicking capabilities was first fabricated. • Polyethyleneimine grafted cellulose was synthesized by a novel approach. • Thiram, parathion methyl, and MG were simultaneously detected on apple peel. [ABSTRACT FROM AUTHOR]

• A facile strategy to fabricate MOFs/cellulose-based composite paper. • The strategy coupled ZIF-8 in situ synthesis with chitosan gelation. • The strategy is compatible with existing paper-making industry.More effective utilization of ZIF-8 (retention rate 75.73 %). • The PM 2.5 removal efficiency was 99.68 % with basis weight 60 g m−2. • The composite paper showed effective photocatalytic disinfection (inhibit zone 12 mm). Metal-organic frameworks (MOFs) have potential in the removal of air hazards such as particulate matter. Cellulose paper is low-cost, renewable and highly industrialized matrix. A facile strategy was proposed in the present work to efficiently integrate MOFs with cellulose paper, with zeolitic imidazolate framework-8 (ZIF-8) as the model. ZIF-8 was in situ synthesis in chitosan gel and subsequently added to the cellulose pulp to fabricate composite paper. The retention rate of ZIF-8 was 75.73 %, which was significantly superior to conventional filling method (4.15 %) and in situ precipitation method (6.52 %). Moreover, ZIF-8 in the composite paper functioned well in aspects of adsorption, filtration and sterilization. The PM 2.5 removal efficiency was 99.68 % with basis weight 60 g·m−2, while the removal efficiency and pressure drop can be modulated by changing the basis weight of composite paper. This strategy may offer ideas to design MOFs/cellulose-based composite materials for particulate matter removal. [ABSTRACT FROM AUTHOR]

Abstract: We have designed the air electrode for rechargeable Li–O2 batteries by adapting conventional current collectors-carbon papers (CPs), as freestanding substrates. The MnO2@CP electrodes are prepared by simply floating CPs on KMnO4 solution at room temperature. CPs act as the reducing agents as well as the freestanding substrates. Birnessite-type MnO2 nanosheets are observed to in situ grow vertically from the surface of CPs, thus building 3D porous architecture. The nanosheets are uniformly distributed and interconnected each other, which contributes to an improved electrical connection among the MnO2 catalyst and CPs. The cycling tests using the electrode as the cathode in rechargeable Li–O2 batteries exhibit high reversibility and superior cycling stability, over 90 cycles with a capacity of more than 1000 mA h (g MnO2)−1 and a high coulombic efficiency of around 100% in the voltage rang of 2.2–4.4 V. [Copyright &y& Elsevier]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite the excellent properties of Pb(Zn1/3Nb2/3)O3-4.5PbTiO3 (PZN-4.5PT) single crystals, the greatest difficulty for their application on electronic devices is to make them to thin layers related to the difficulty to make them as ceramic materials. In this paper, we use the combined USAXS/SAXS/WAXS instrument at 9ID beamline at APS-ANL for in situ characterization of PZN-4.5PT inorganic perovskite nanoparticles thin films deposited on nanotextured silicon to understand the phase transitions and determine the observed microcrystals' structure. The sample was annealed from ambient to 1000°C. The results revealed structure changes in the nanoparticles' thin films which could be explained by the new phase that can be assigned to the Pb3(PO4)2-based component. The peak at 31° indicates the presence of the rhombohedral phase perovskites assigned to the nanoparticles. WAXS characterization permitted to identification of many transitions during thermal annealing like dehydration or dihydroxylation of phosphorus gel –OH bonds and internal water. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Photocatalytic reduction of O2 to generate H2O2 shows an excellent environment friendly nature and the controllable H2O2 concentrations and is found the prospect of applications in H2O2‐assisted redox. In this paper, MIL‐68(In) is chosen as a sacrifice precursor to construct a multi‐component photocatalyst of In2O3/In2S3/C by integrated in situ sulfidation and pyrolysis routes. The resulting In2O3/In2S3/C inherited the geometry of MIL‐68(In) and represents the hollow microtube with rough surface. The photocatalytic activity of the In2O3/In2S3/C in H2O2 generation is investigated systematically, and the contrast tests were conducted over the In2S3/MIL‐68 synthesized by in situ sulfidation but without subsequent pyrolysis, to explore the advantages of the In2O3/In2S3/C heterostructure. The best photocatalytic H2O2 evolution is observed by the In2O3/In2S3/C with a value of 934.6 μmol/L within 1 h, which is higher than that by In2S3/MIL‐68 and other previously reported photocatalysts. The photoelectrochemical analyses and ESR measurements clarify that contact heterojunction and matched band potentials are responsible for the effective separation of electrons and holes, and the O2·‐ are the main active species in the photocatalytic H2O2 evolution. The outstanding photocatalytic activity, structure stability, and the easily regulated H2O2 concentrations render the In2O3/In2S3/C the prospect applications in the H2O2‐assisted redox reactions. [ABSTRACT FROM AUTHOR]

In this paper, ZnO‐containing coatings were prepared on the surface of AZ31B magnesium alloy by a simple one‐step micro‐arc oxidation method using zinc gluconate as the zinc source. The microstructure, elemental distribution, phase composition and chemical composition of the coatings were analyzed by scanning electron microscopy (SEM), energy spectrometry (EDS), X‐ray diffractometry (XRD) and X‐ray photoelectron spectroscopy (XPS), potentiodynamic polarization tests and electrochemical impedance spectroscopy were carried out in simulated body fluids to study the corrosion behavior of the coatings. The results show that introducing Zn2+ into the coatings reduces the number of pores and changes the microstructure of the coatings, resulting in improving corrosion resistance. In addition, the corrosion current density of the coatings prepared by adding 6 g/L of zinc gluconate was approximately two orders of magnitude lower than that of the coatings prepared without adding zinc gluconate. [ABSTRACT FROM AUTHOR]

In this paper, FeMn-ZSM-5/MOR(FeMn-Z/M) catalyst was synthesized through in-situ crystallization and wet impregnation method and used as heterogeneous Fenton-like catalyst for degradation of indigo carmine (IC) in aqueous solution. The catalysts were characterized using XRD, BET, SEM, EDS, FT-IR and XPS techniques. The experimental results showed that Fe and Mn were successfully doped onto the ZSM-5/MOR(Z/M) surface. The combination of ZSM-5 and mordenite (MOR) not only enhanced the adsorption capacity of contaminant, but also had more active sites. Degradation experiments and the valence variations indicated that Fe and Mn had a significant synergistic effect. The results of IC degradation experiments under different conditions showed that the optimum conditions (FeMn mass ratio = 1:2, FeMn-Z/M = 25 mg, H2O2 = 0.5 ml, pH = 3), the degradation rate of IC reaches 99% in 20 min. Reaction analyses showed that catalyst follow a first-order reaction kinetic. The degradation of IC could be divided into two stages: adsorption/oxidation (After adsorption, oxidative degradation begins) and Fenton-like reaction. Free radicals quenching studies analyzed verified that the dominant free radicals within FeMn-Z/M Fenton-like system were hydroxyl radical (·HO) and hydro-peroxy radical (·HO2), ·HO2 was the main free radical in the adsorption/oxidation stage. The possible catalytic mechanism was proposed. Finally, the synthesized FeMn-Z/M catalyst had better performance than other IC removal methods, and had good degradation efficiency and high reusability after multiple runs. [ABSTRACT FROM AUTHOR]

The paper considers the development of a technological scheme for preparing metal matrix nanocomposites based on the interaction between nanodiamond reinforcing particles and a chromium matrix when being heated, forming chromium carbide nanoparticles. These carbides are in situ synthesized ceramic reinforcing nanoparticles. The first stage of preparing composites is to obtain composites with the chromium matrix and nanodiamond reinforcing particles. For this purpose, mechanical alloying is used, i.e., processing in planetary mills. The size of a primary nanodiamond particle is 5 nm, but they are combined in agglomerates that are hundreds of micrometers in size. The time of processing in the planetary mill defines the crushing degree of the agglomerates. In this study, processing was carried out for 0.5 h, 2 h, and 4 h. The second stage for obtaining composites with reinforcing particles of chromium carbides is thermal processing. Explorations using the method of differential scanning calorimetry showed that reducing the size of nanodiamond reinforcing particles (by prolonging the time of processing in the planetary mill) leads to a decrease in the initial temperature of the reaction for developing carbides. The worked-out technique for obtaining composites was patented in the Russian Federation (the patent for invention 2772480). [ABSTRACT FROM AUTHOR]

Summary: In this work, we in situ synthesized C‐CuO composite by a facile solid phase grinding for efficient photo‐thermal conversion. Moreover, surface morphology, hydrophilicity property, light absorption characteristic, and evaporation performance were investigated on C‐CuO membrane. It can be seen that C‐CuO composite was well dispersed on the membrane, prompting light harvesting and intentionally encouraging water evaporation. The surface hydrophilicity assisted valid water flow by the membrane toward the heat localization zone and smooth steam escape. At a calcination temperature of 250°C and a mass ratio of 1:1 regarding the preparation of C‐CuO composite, surface temperature of C‐CuO membrane reached to the maximum value around 87.4°C, noticeably stimulating the conversion of water to vapor. Further, the evaporation system with 0.015 g C‐CuO composite loading possessed top‐quality evaporation performance with superior recyclability, which mirrored to 92.6% evaporation efficiency and 1.34 kg m−2 hours−1 evaporation rate after 30 minutes exposure to light, respectively. Our work suggested that in situ synthesized C‐CuO composite was regarded as a potential alternative for clean water production by solar‐driven interfacial evaporation. [ABSTRACT FROM AUTHOR]

Silicon/carbon (Si/C) composite shows great potential to replace graphite as lithium-ion battery (LIB) anode owing to its high theoretical capacity. Exploring low-cost scalable approach for synthesizing Si/C composites with excellent electrochemical performance is critical for practical application of Si/C anodes. In this study, we rationally applied a scalable in situ approach to produce Si-carbon nanotube (Si-CNT) composite via acid etching of commercial inexpensive micro-sized Al-Si alloy powder and CNT mixture. In the Si-CNT composite, ∼10 nm Si particles were uniformly deposited on the CNT surface. After combining with graphene sheets, a flexible self-standing Si-CNT/graphene paper was fabricated with three-dimensional (3D) sandwich-like structure. The in situ presence of CNT during acid-etching process shows remarkable two advantages: providing deposition sites for Si atoms to restrain agglomeration of Si nanoparticles after Al removal from Al-Si alloy powder, increasing the cross-layer conductivity of the paper anode to provide excellent conductive contact sites for each Si nanoparticles. When used as binder-free anode for LIBs without any further treatment, in situ addition of CNT especially plays important role to improve the initial electrochemical activity of Si nanoparticles synthesized from low-cost Al-Si alloy powder, thus resulting in about twice higher capacity than Si/G paper anode. The self-standing Si-CNT/graphene paper anode exhibited a high specific capacity of 1100 mAh g −1 even after 100 cycles at 200 mA g −1 current density with a Coulombic efficiency of >99%. It also showed remarkable rate capability improvement compared to Si/G paper without CNT. The present work demonstrates a low-cost scalable in situ approach from commercial micro-sized Al-Si alloy powder for Si-based composites with specific nanostructure. The Si-CNT/graphene paper is a promising anode candidate with high capacity and cycling stability for LIBs, especially for the flexible batteries application. [ABSTRACT FROM AUTHOR]

All studies on oxygen‐evolution reaction by Mn oxides in the presence of cerium(IV) ammonium nitrate (CAN) have been so far carried out by synthesizing Mn oxides in the first step. And then, followed by the investigation of the Mn oxides in the presence of oxidants for oxygen‐evolution reaction (OER). This paper presents a case study of a new and promising strategy for in situ catalyst synthesis by the adding MnII to either CAN or KMnO4/CAN solution, resulting in the formation of Mn‐based catalysts for OER. The catalysts were characterized by scanning electron microscopy, energy‐dispersive spectroscopy, transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, X‐ray absorption spectroscopy, and X‐ray photoelectron spectroscopy. Both compounds contained nano‐sized particles that catalyzed OER in the presence of CAN. The turnover frequencies for both catalysts were 0.02 (mmolO2 /molMn⋅s). [ABSTRACT FROM AUTHOR]

The biodeterioration of cultural heritage monuments is a worldwide phenomenon, closely linked to the presence of microorganisms and macroorganisms. Microbial colonization leads to physical, chemical damage and esthetic changes. Synthetic polymers, particularly acrylics, are often used to consolidate and protect monuments and artistic stone surfaces. To increase acrylics performances regarding to durability and antimicrobials' activity, nanoparticles (NPs) were added to polymers. In this study, silver NP was biosynthesized by Malva sylvestris aqueous extract. Furthermore, the in situ method was used for nanocomposite synthesis, which would be simplified the procedure of synthesis. For this, the precursors including the plant aqueous extract, AgNO3 solution and polymer were mixed, and nanocomposite was formed. The morphological characteristics of the obtained nanocomposite were determined using field emission scanning electron microscope (FESEM). The energy-dispersive X-ray (EDX) confirmed AgNPs existence in the composite. Next, the nanocomposite's antibacterial properties were tested on Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Cladosporium cladosporioides, Aspergillus niger, and Alternaria alternata. The antibacterial activity of bioengineered nanocomposite compared to acrylic polymer, alone. The results of antimicrobial experiments have shown that the number of bacterial and fungal cells was decreased by 1 logarithm in the polymer, and by 2 to 4 logarithms in the nanocomposite that the antimicrobial effect of latter was notably increased. This study was based on applying this nanocomposite to improve conservation strategies for stony cultural heritage. Further experiments should be performed to evaluate the efficacy of this nanocomposite on outdoor stony model. [ABSTRACT FROM AUTHOR]

In this paper, Al-CaB6 alloys were prepared by in situ melt reaction. The CaB6 particles through in situ growth are cubic with a regular shape, evenly distributed in the Al matrix. By edge-to-edge matching model’s calculation, mismatch between CaB6 particles and α-Al was ~2.34%, which is less than 6%, so CaB6 can serve as the core of α-Al nucleation. When the amount of CaB6 addition reaches 6 wt.%, hardness of the Al-CaB6 alloy reached 34.4 HV. Besides, CaB6-particle reinforced hypereutectic Al-Si composites were prepared, and the positive influence of CaB6 particles on microstructure and properties of hypereutectic Al-Si composites was studied. The CaB6 particles show significant effect on the modification of primary silicon. Owing to the addition of CaB6 particles, the hardness of hypereutectic Al-Si alloys increased and the hardness of Al-18Si-CaB6 reached 95.1 HV. The electrochemical test of the manufactured composites revealed that the corrosion resistance of Al-18Si-CaB6 composites improved as the amount of CaB6 particle content increased. This work serves as a reference for the investigation of Al and Al-Si composites reinforced with ceramic particles. [ABSTRACT FROM AUTHOR]

It is well-established that the structural, morphological and performance characteristics of nanoscale materials critically depend upon the dispersion state of the nanofillers that is, in turn, largely determined by the preparation protocol. In this report, we review synthetic strategies that capitalise on the in situ generation of nanoparticles on and within polymeric materials, an approach that relies on the chemical transformation of suitable precursors to functional nanoparticles synchronous with the build-up of the nanohybrid systems. This approach is distinctively different compared to standard preparation methods that exploit the dispersion of preformed nanoparticles within the macromolecular host and presents advantages in terms of time and cost effectiveness, environmental friendliness and the uniformity of the resulting composites. Notably, the in situ-generated nanoparticles tend to nucleate and grow on the active sites of the macromolecular chains, showing strong adhesion on the polymeric host. So far, this strategy has been explored in fabrics and membranes comprising metallic nanoparticles (silver, gold, platinum, copper, etc.) in relation to their antimicrobial and antifouling applications, while proof-of-concept demonstrations for carbon- and silica-based nanoparticles as well as titanium oxide-, layered double hydroxide-, hectorite-, lignin- and hydroxyapatite-based nanocomposites have been reported. The nanocomposites thus prepared are ideal candidates for a broad spectrum of applications such as water purification, environmental remediation, antimicrobial treatment, mechanical reinforcement, optical devices, etc. [ABSTRACT FROM AUTHOR]

The addition of nanostructures to polymeric materials allows for a direct interaction between polymeric chains and nanometric structures, resulting in a synergistic process through the physical (electrostatic forces) and chemical properties (bond formation) of constituents for the modification of their properties and potential cutting-edge materials. This study explores a novel in situ synthesis method for PDMS-%SiO2 nanoparticle composites with varying crosslinking degrees (PDMS:TEOS of 15:1, 10:1, and 5:1); particle concentrations (5%, 10%, and 15%); and sol-gel catalysts (acidic and alkaline). This investigation delves into the distinct physical and chemical properties of silicon nanoparticles synthesized under acidic (SiO2-a) and alkaline (SiO2-b) conditions. A characterization through Raman, FT-IR, and XPS analyses confirms particle size and agglomeration differences between both the SiO2-a and SiO2-b particles. Similar chemical environments, with TEOS and ethanol by-products, were detected for both systems. The results on polymer composites elucidate the successful incorporation of SiO2 nanoparticles into the PDMS matrix without altering the PDMS's chemical structure. However, the presence of nanoparticles did affect the relative intensities of specific vibrational modes over composites from −35% to 24% (Raman) and from −14% to 59% (FT-IR). The XPS results validate the presence of Si, O, and C in all composites, with significant variations in atomic proportions (C/Si and O/Si) and Si and C component analyses through deconvolution techniques. This study demonstrates the successful in situ synthesis of PDMS-SiO2 composites with tunable properties by controlling the sol-gel and crosslinking synthesis parameters. The findings provide valuable insights into the in situ synthesis methods of polymeric composite materials and their potential integration with polymer nanocomposite processing techniques. [ABSTRACT FROM AUTHOR]

The design and synthesis of macrocyclic ligands has become a hot research field of coordination chemistry for their novel structures and intriguing properties. Starting from bis (5-amion-1H-1,2,4-triazole) ligand (L1), three macrocyclic complexes with a novel double bis-triazole macrocyclic ligand (L2), [MCl2L2] (M = Fe, Co, Ni), were designed and synthesized byin situreaction. In the process of reaction, metal ions played a key role for contributing to the formation of novel macrocyclic structures. The molecular structures of complexes were characterized by single-crystal X-ray diffraction, and the detailed description of synthesis is presented in this paper. The fluorescence quenching spectra and UV–vis spectra were used to study the interaction of complexes with bovine serum albumin (BSA). The results showed that the fluorescence quenching of BSA by these complexes was the presence of static quenching. [ABSTRACT FROM AUTHOR]

This paper reviews the coordination chemistry of polypyrazolylmethylamines as tripodal tetradentate (LS = N,N,N-tris(3,5-dimethylpyrazol-1-ylmethyl)amine) and dipodal tridentate (LD = N,N,-bis(3,5-dimethylpyrazol-1-ylmethyl)amine) ligands. References to the methods for the synthesis of both the ligands alone and their transition metal complexes are given with emphasis placed on the structural features of the latter. Special attention was paid to the one-pot synthesis, which is a new method for isolation of various metal complexes with N,N-bis- and N,N,N-trispyrazolylmethylamines and co-ligands, such as urotropine and 3,5-dimethylpyrazole. The complexes in question were createdin situfrom 1-hydroxymethyl-3,5-dimethylpyrazole (L0) and zerovalent metals. [ABSTRACT FROM PUBLISHER]

The aerobic photooxidation of sulfides into sulfoxides in eco-friendly solvents, notably water, at room temperature, represents a significant interest in the domain of synthetic chemistry. This study introduces four highly stable hexadentate Ir(III) complexes: [Ir(fpqen)](PF6) (1), [Ir(btqen)](PF6) (2), [Ir(bmpqen)](PF6) (3), and [Ir(bnqen](PF6) (4) (where bfpqen is N,N′-bis(2-(4-fluorophenyl)quinolin-8-yl)ethane-1,2-diamine, btqen is N,N′-bis(2-(4-tolyl)quinolin-8-yl)ethane-1,2-diamine, bmpqen is N,N′-bis(2-(4-methoxyphenyl)quinolin-8-yl)ethane-1,2-diamine, and bnqen is N,N′-bis(2-naphthylquinolin-8-yl)ethane-1,2-diamine). These complexes were synthesized utilizing an in situ inter-ligand C-N cross-coupling photoreaction of the precursors [Ir(L)2(en)](PF6) (L is 2-(4-fluorophenyl)quinoline, (2-(4-tolyl)quinoline, 2-(4-methoxyphenyl)quinoline or 2-naphthylquinoline, and en is 1,2-diamine) under benign conditions. This methodology furnishes a valuable and complementary approach for the in situ generation of multidentate complexes through a post-coordination inter-ligand-coupling strategy under mild conditions. Moreover, these hexadentate Ir(III) complexes exhibit pronounced catalytic activity and chemo-selectivity toward the aerobic photooxidations of sulfides into sulfoxides in aqueous media at room temperature, offering a new avenue for the sustainable synthesis of sulfoxides. [ABSTRACT FROM AUTHOR]

Nowadays, due to the increasing number of diseases and injuries related to bone tissue, there is an acute problem of creating a material that could be incorporated into the bone tissue structure and contribute to accelerated bone regeneration. Such materials can be represented by a polymeric matrix that holds the material in the bone and an inorganic component that can be incorporated into the bone structure and promote accelerated bone regeneration. Therefore, in this work we investigated polyvinyl alcohol-based composite cryogels containing an in situ deposited inorganic filler, hydroxyapatite. The freezing temperature was varied during the synthesis process. The composition of the components was determined by infrared spectroscopy and the phase composition by X-ray phase analysis, from which it was found that the main phase of the composite is hydroxyapatite and that the particle size decreases with increasing freezing temperature. The elemental composition of the surface is dominated by carbon, oxygen, phosphorus and calcium; no impurities of other elements not typical for polyvinyl alcohol/ hydroxyapatite cryogels were found. Higher mechanical properties and melting points were observed at −15 °C. Cryogenic treatment parameters did not affect cell viability; however, cell viability was above 80% in all samples. [ABSTRACT FROM AUTHOR]

Spray technique was used for the adsorption of in-situ silver nanoparticles (AgNPs) onto and inside the surface of nano- and micro- fibrillar cellulose (NFC and MFC) as well as filter paper. The abundance of hydroxyl and carboxyl groups located in NFC and MFC are used to stabilize Ag ions (Ag + ) which were then in-situ reduced to (AgNPs) by chemical or UV reduction. The surface characteristic features, elemental analysis, particle size as well as size distribution of the obtained MFC, NFC and filter paper loaded with AgNPs were characterized via field emission scanning electron microscopy connected to energy dispersive X-ray spectroscopy (FESEM- EDX) and transmission electron microscopy (TEM). The associated chemical changes after growth of AgNPs onto the cellulose substrates were assessed by fourier transform infra-red (FT-IR) while the thermal stability of such systems were investigated by thermogravimetrical analyses (TGA). The antibacterial properties of AgNPs loaded NFC, MFC and filter paper as well was investigated against Escherichia Coli. The resulted data indicate that the particle size was found to be 11 and 26 nm for AgNPs nucleated on NFC and MFC—based papers respectively. The antibacterial activity of AgNPs loaded MFC exhibited higher antibacterial activity than that of AgNPs loaded NFC. Overall, the present research demonstrates facile and fast method for in-situ antibacterial AgNPs loading on cellulose substrates. [ABSTRACT FROM AUTHOR]

Copyright of Kemija u Industriji is the property of Croatian Society of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, (Cr, Fe)7C3(M7C3)/ γ-Fe composite layer has been in situ fabricated on a low carbon steel surface by vacuum electron beam irradiation (VEB). Three kinds of powder mixtures were placed on a low carbon steel substrate, which was then irradiated with electron beam in vacuum condition. The microstructure and wear resistance of the composite layers has been studied by means of optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), microhardness tester and tribological tester. The chemical composition of all specimens were carefully analyzed using energy-dispersive X-ray spectroscopy (EDAX) technique. Depending on three different powder mixtures, hypereutectic and hypoeutectic microstructures were obtained on surface composite layers. No pores and cracks were found on the coatings. The amount of carbides formed in the surface composite layer was mainly determined by carbon concentration. The microstructure close to the fusion line was largely primary austenite dendrite. The hardness and wear resistance of the surface composite layer has been greatly improved due to the extensive distribution of carbides. [ABSTRACT FROM AUTHOR]

The integration of organic and inorganic materials has been widely used in various applications to generate novel functional nano-materials characterized by unique properties. Functional crystalline framework nanosheets and their synergistic effects have been studied recently for possessing the advantages of functional species as well as crystalline framework nanosheets. Hence, we have focused on the preparation methods and applications of functional crystalline framework nanosheets in this review. We introduced crystalline framework nanosheets and discussed the importance of integrating functional species with nanosheets to form functional crystalline framework nanosheets. Then, two aspects of the preparation methods of functional crystalline framework nanosheets were reviewed: in situ synthesis and post-synthesis modification. Subsequently, we discussed the properties of the crystalline framework nanosheets combined with various functional species and summarized their applications in catalysis, sensing, separation, and energy storage. Finally, we have shared our insights on the challenges of functional crystalline framework nanosheets, hoping to contribute to the knowledge base for optimizing the preparation methods, expanding categories, improving stability, and exploring potential applications. [ABSTRACT FROM AUTHOR]

In this study, a facile method for preparation of bamboo viscose fibers composite silver nanoparticles by in-situ synthesis was investigated. The bamboo viscose fiber was used as both reducing and protecting agents, and it was reacted with different concentrations of AgNO3 solutions under high temperature and high pressure. The structure and properties of the composites were analyzed by ultraviolet visible spectroscopy analysis, X-ray diffraction analysis, and scanning electron microscopy. The results show that the reaction products are spherical or near-spherical silver nanoparticles with the face-centered cubic geometry. The silver nanoparticles are dispersed uniformly on the surface of the bamboo viscose fibers with the size range of 10–60 nm. A mechanism was proposed where the silver nanoparticles are uniformly loaded onto the bamboo viscose fibers by bonding with the hydroxyl groups containing in the cellulose macromolecules. The antibacterial properties of the bamboo viscose fiber/silver nanoparticles against Escherichia coli and Staphylococcus aureus were tested by inhibition zone and dynamic shake flask methods. The results show that when the concentration of AgNO3 solution participating in the reaction was 0.001 M, the antibacterial rate of the composite material on the two kinds of bacteria could reach more than 99%. According to these results, the bamboo viscose fiber/silver nanoparticles nanocomposites with the excellent antibacterial properties offer a potential opportunity to be used as functional antimicrobial fabrics and medical devices. [ABSTRACT FROM AUTHOR]

Uric acid (UA) is a blood and urine component obtained as a metabolic by‐product of purine nucleotides. Abnormalities in UA metabolism cause crystal deposition as monosodium urate and lead to various diseases such as gout, hyperuricemia, Lesch–Nyhan syndrome, etc. Monitoring these diseases requires a rapid, sensitive, selective, and portable detection approach. Therefore, this study demonstrates the hydrothermal synthesis of CuFe2O4/reduced graphene oxide (rGO) nanocomposite for selective detection of UA. After the nanocomposite synthesis, characterization was performed by X‐ray diffraction spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, X‐ray photoelectron spectroscopy, UV–visible spectrometry, atomic force spectroscopy, scanning electron microscopy, and electrochemical analysis. Furthermore, from the electrochemical analysis using cyclic voltammetry (CV), kinetic studies were carried out by varying the scan rate to obtain the diffusion coefficient, surface concentration, and rate of charge transfer to achieve a calibration curve that indicates the quasi reversible nature of the fabricated electrode with a linear regression coefficient of oxidation (R2: 0.9992) and reduction (R2: 0.9971) peaks. Moreover, the fabricated nonenzymatic amperometric sensor to detect UA with a linearity (R2: 0.9989) of 1–400 μM was highly sensitive (2.75 × 10−4 mAμM−1 cm−2) and had a lower limit of detection (0.01231 μM) at pH 7.5 in phosphate‐buffered saline solution. Therefore, the CuFe2O4/rGO/ITO‐based nonenzymatic sensor could detect interfering agents and spiked real bovine serum samples with higher sensitivity and selectivity for UA detection. [ABSTRACT FROM AUTHOR]

This literature review aims to summarize the research conducted on the production of locally reinforced ferrous castings based on metal matrix composites reinforced with TiC (TiC-MMCs). One way to improve the wear resistance of cast components is to reinforce critical regions locally with metal matrix composites (MMCs) without changing the toughness of the component core. The in situ method of self-propagating high-temperature synthesis is one of the main approaches for the production of this enhanced material. Using this approach, the reinforcement is formed from a powder compact inserted in the mold cavity. The temperature of the liquid metal then produces the combustion reactions of the powders, which promote the formation of the ceramic phase. This paper focuses on eight powder systems used to synthesize TiC: Ti-C, Ni-Ti-C, Ni-Ti-B4C, Fe-Ti-C/Fe-Cr-Ti-C, Cu-Ti-B4C, Al-Ti-C, and Al-Ti-B4C, and provides an overview of the methodologies used as well as the effect of processing variables on the microstructural and mechanical characteristics of the reinforcement zones. [ABSTRACT FROM AUTHOR]

As is well known, it is hard to prepare ceramic-Ag composites, owing to the lower melting temperature of silver. In this paper, Si 3 N 4 -based composites reinforced with in situ formation of Ag particles were successfully fabricated by sintering Si 3 N 4 and AgNO 3 , and their microstructure, elevated-temperature mechanical and tribological properties were investigated. It can be found that Ag particles about 1 µm were uniformly dispersed into the Si 3 N 4 matrix and there was no outflow of silver during the sintering. Meanwhile, S 3 N 4 /Ag composite containing 5.1 wt% silver exhibited the best fracture toughness, 7.05 MPa m 1/2 and 6.12 MPa m 1/2 at 25 °C and 600 °C, respectively, and the plastic deformation and crack bridging of silver were responsible for the high toughness. Besides, the friction coefficient and wear rate of composites were continuously reduced as the silver content increases. Especially at 200 °C, the friction coefficients reached the lowest value due to the formation of an amorphous silicon oxide film. And the wear resistance was enhanced by the cooperative strengthening effect of silver toughening and lubricating. [ABSTRACT FROM AUTHOR]

In this paper, reduced graphene oxide/gold nanoparticle/Nafion (rGO/AuNP/Nafion) modified electrode was fabricated through in-situ synthesis and used for determination of copper ions in strong salt electrolyte (0.5 M NaCl) by differential pulse anodic stripping voltammetry (DPASV). This in-situ synthesis procedure was based on the ion-exchange and electrochemical reduction. The use of rGO provided a larger electrode surface and the presence of more active sites, while electron transfer was accelerated by incorporating AuNPs. Nafion was utilized as a cation exchange polymer in which rGO and AuNPs could be tightly attached to the electrode surface. The physical and electrochemical characterizations of the as-prepared modified electrode were studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and cyclic voltammetry. AuNPs with diameter of 5–10 nm on rGO decorated in the gold electrode surface were observed. Under the optimal conditions, the rGO/AuNP/Nafion electrode had a linear response to copper ions in the concentrations range from 20 nM to 1 μM (R 2 = 0.998), with the lowest detectable concentration of 8 nM and the detection limit of 4 nM (S/N = 3). Additionally, this electrode was successfully applied to the speciation analysis of copper (free, dissolved and total) in seawater. [ABSTRACT FROM AUTHOR]

Self-assembly of flakes to form three-dimensional flower-like structure is an effective way to strengthen electromagnetic absorption capability. However, it still remains a great challenge to synthesis of such structure, especially the preparation of flower-like Fe particles. In this paper, hierarchical flower-like α-Fe particles with a diameter of ∼3 μm are prepared by combining a simple in situ reduction method and assisted with an appropriate external magnetic field at normal atmosphere. A possible mechanism for the formation of flower-like structure related to the synergy of magnetic field and hydrogen bubble which generated by in-situ reduction reaction is proposed. The electromagnetic properties of flower-like α-Fe-paraffin composites were measured with the coaxial reflection/transmission technique at 2–18 GHz. The minimal reflection loss value of −33.1 dB is obtained at 17.46 GHz. Moreover, the effective absorption bandwidth with reflection loss exceeding −10 dB is up to 6.2 GHz (7.7–13.9 GHz) at a thickness of 3 mm, which covers whole of the X-band (8–12 GHz) and part of the Ku-band (12–18 GHz). These excellent absorbing performances suggesting that the flower-like α-Fe particles synthesized here could be an extremely promising electromagnetic absorbing material. [ABSTRACT FROM AUTHOR]

Biocompatible nanoparticles have attracted considerable attention as cellular antioxidant agents for the improvement of new therapeutics for several and diverse oxidative stress related disorders. Here, it is shown that the biocompatible cell membrane@gold nanoparticle displays catalase‐mimic behavior by decomposing H2O2. This interesting behavior can be used for cell protection against induced oxidative injury by reactive oxygen species (ROS). So, after characterizing this novel biocompatible nanostructure, the protective effect of cell membrane@AuNPs pretreatment in front of a well‐defined oxidative stress‐inducing chemotherapy drug, doxorubicin (Dox) is assessed. Doxorubicin pretreatment significantly reduces the intracellular ROS production. Similarly, a reduction in the levels of DNA oxidative damage, as measured with the AO/EB staining, is also observed. Obtained results would support that this novel nanostructure can show how a pharmacological agent can be used against oxidative stress‐mediated diseases. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation is an environmentally friendly way to eliminate environmental pollution. Exploring a photocatalyst with high efficiency is essential. In the present study, we fabricated a Bi2MoO6/Bi2SiO5 heterojunction (BMOS) with intimate interfaces via a facile in situ synthesis method. The BMOS had much better photocatalytic performance than pure Bi2MoO6 and Bi2SiO5. The sample of BMOS-3 (3:1 molar ratio of Mo:Si) had the highest removal efficiency by the degradation of Rhodamine B (RhB) up to 75% and tetracycline (TC) up to 62% within 180 min. The increase in photocatalytic activity can be attributed to constructing high-energy electron orbitals in Bi2MoO6 to form a type II heterojunction, which increases the separation efficiencies of photogenerated carriers and transfer between the interface of Bi2MoO6 and Bi2SiO5. Moreover, electron spin resonance analysis and trapping experiments showed that the main active species were h+ and •O2− during photodegradation. BMOS-3 maintained a stable degradation capacity of 65% (RhB) and 49% (TC) after three stability experiments. This work offers a rational strategy to build Bi-based type II heterojunctions for the efficient photodegradation of persistent pollutants. [ABSTRACT FROM AUTHOR]

This work details the enzymatic generation of fluorescence nanomaterials and the use of this optical signal as the analytical parameter for the quantification of the substrate. More specifically, fluorescent copper nanoclusters have been obtained during the enzymatic reaction of tyramine oxidase and tyramine in the presence of Cu(II); the fluorescence intensity being proportional to the concentration of tyramine. The nanoclusters obtained show fluorescence at 445 nm by being excited at 320 nm and have been characterized by TEM, EDX, and XPS. The formation mechanism has also been studied, suggesting that under the optimal conditions (0.1 M MES buffer and pH = 6), the formation of the nanoclusters is due to the reducing properties of the product of the enzymatic reaction (p-hydroxybenzaldehyde) in MES buffer. The method shows a linear relationship with the concentration of tyramine in the range from 1.0·10−5 to 2.5·10−4 M, a RSD of 3% (n = 5) and a LOD of 6.3·10−6 M. The method has been applied to the determination of tyramine in sausage with good results. [ABSTRACT FROM AUTHOR]