Sharif Digital Repository

In the bone tissue engineering field (BTE), it is of significant importance to develop bioactive multifunctional scaffolds with enhanced osteoconductivity, osteoinductivity, and antibacterial properties required for lost bone tissue regeneration. In this work, a bioactive glass-ceramic scaffold was manufactured via a novel polymer-derived ceramics (PDC) manufacturing method. To gain antibacterial properties, the silver ions were incorporated in controlled amount along with other precursors in the PDC processing stage. Microstructural and structural properties of the fabricated silicate-phosphate glass-ceramic scaffold were evaluated by scanning electron microscopy (SEM) equipped with energy... 

Topology, symmetry, electron correlations, and the interplay between them have formed the cornerstone of our understanding of quantum materials in recent years and are used to identify new emerging phases. While the first two give a fair understanding of noninteracting and, in many cases, weakly interacting wave function of electron systems, the inclusion of strong correlations could change the picture substantially. The Kondo lattice model is a paradigmatic example of the interplay of electron correlations and conduction electrons of a metallic system, describing heavy fermion materials and also fractionalized Fermi liquid pertaining to an underlying gauge symmetry and topological orders.... 

Exploring bi-functional electrocatalysts with excellent activity, good durability, and cost-effectiveness for electrochemical hydrogen and oxygen evolution reactions (HER and OER) in the same electrolyte is a critical step towards a sustainable hydrogen economy. Three main features such as high density of active sites, improved charge transfer, and optimized electronic configuration have positive effects on the electrocatalyst activity. In this context, understanding structure–composition–property relationships and catalyst activity is very important and highly desirable. Herein, for the first time, we present the design and fabrication of novel MOF-derived ultra-small Ru/RuO2 nanoparticles... 

With the advent of the Internet of Things (IoT), the development of self-powered sensors has received much attention. Introducing triboelectric nanogenerators (TENGs) as a power source that converts mechanical movement into electrical signals has been admired recently. Moreover, the monitoring of humidity has become enormously essential in several technological contexts from environment monitoring to biomedical applications, thus joining these two subjects provides a huge benefit in achieving self-powered humidity sensors. Here, in this research, facile, low-priced and self-powered humidity sensors are fabricated utilizing transition-metal dichalcogenides (TMD) nanosheets. Semi-vertical SnS2... 

The oxygen evolution reaction (OER) with its sluggish kinetics has imposed a significant barrier to the sustainable and green generation of hydrogen fuel (via electrolysis of water) and the development of metal-air batteries. In this study, we report an efficient and novel OER electrocatalyst based on NiSe2nanoparticles (NPs) and the naturally abundant halloysite clay mineral. The NiSe2/halloysite nanocomposite (NiSe2/H) was prepared by a simple one-step hydrothermal route. The electrocatalytic performance of the as-synthesized nanocomposite and its components (pristine NiSe2and halloysite) toward OER in 1.0 KOH solution was examined. The NiSe2/H nanocomposite exhibited a significantly... 

Sulfur dioxide (SO2) is one of the acidic components found in the flue gas that can harm industrial facilities and the environment. SO2 adsorption by metal-organic frameworks (MOFs) is an emerging method to effectively remove SO2 in low concentrations from the gas mixtures. In this study, amino-functionalized MIL-53(Al), i.e., NH2-MIL-53(Al), was synthesized through the solvothermal method and examined for SO2 adsorption at relatively moderate pressure and temperature (up to 2 bar, 25-80 °). According to the results of XRD, FT-IR, TGA, and DSC analysis, NH2-MIL-53(Al) demonstrated appropriate water, acid, and thermal stability. The SO2 adsorption capacity of NH2-MIL-53(Al) was 5.21 mmol.g-1... 

Metal manufacturing plants, nuclear power plants (which produce steam, by using thermal energy yielded during the nuclear fission, for spinning enormous turbines to generate electricity), and geothermal power plants are a few in the extensive list of technologies where different processes occur in high temperature environment in the presence of strong magnetic fields. Nanofluids (NFs), on the other hand, have been successful in achieving wide acceptance as the next generation coolant in the above mentioned industries as well as in the automobiles, heat exchangers, and steam boilers, owing to their remarkable thermal performance. These observations motivate the authors to explore the change... 

Novel Bi2S3/NiCo2O4 nanocomposites (BS/NCO) with various mass ratios were prepared using NiCo-MOF as precursor. The morphology, composition and structure of the as-prepared catalysts were studied by different techniques such as FE-SEM, EDX, XRD, FT-IR, VSM and BET. The as-synthesized composite with 20 % Bi2S3 (%20 BS/NCO) demonstrated the best performance in reduction reaction of 4-nitrophenol (4-NP). The enhanced catalytic activity of %20 BS/NCO composite compared to the Bi2S3 and NiCo2O4 can be assigned to the optimized synergistic effects between the two pristine materials. Thermodynamic parameters and the activation energy of the reaction in the presence of %20 BS/NCO composite were... 

Bacterial infection is one of the biggest challenges in wound healing and imposes enormous burden on patient and medical system. Moreover, multidrug resistant microorganisms (MDR) limit the usage of therapeutic agents including antibiotics for wound treatment. Hydrogels are three-dimensional networks that have emerged as efficient scaffolds for the treatment of infected wounds. In addition to their intrinsic antibacterial activities, hydrogels are able to load and release therapeutic agents to keep the efficient dose during wound healing process. At the same lines, incorporation of metal nanoparticles (NPs) into hydrogels boosts their antibacterial activity. Moreover, photothermal agents... 

The development of active and stable materials has great importance for the commercialization of nickel-zinc (Ni–Zn) batteries and hydrogen production. Transition metal sulfides have good theoretical properties for these applications. In this research, we present the synthesis and characterization of Ni3S2@MoS2 nanocatalyst and its hybrid with reduced graphene oxide (Ni3S2@MoS2-rGO). The capability of these materials is investigated as cathode material for Ni–Zn batteries and hydrogen evolution in alkaline media. In the case of Ni–Zn batteries, the assembled Ni3S2@MoS2-rGO//Zn battery shows a discharge capacity of 249.3 mAh g−1 with coulombic efficiency of 97.2%, showing a higher... 

Freshwater scarcity in conjunction with population expansion puts human survival in doubt. Throughout the world, millions of people are deprived of clean and safe drinking water. The development of novel technologies to desalinate water is among the most valuable studies for humanity. Receiving benefits from low energy consumption, high environmental capability, and low-production cost, capacitive deionization (CDI) received significant attention in saline water desalination. Rational design of efficient electrode materials by tailoring their structural and compositional properties, therefore, plays a pivotal role in achieving high-performance CDI systems. Hollow carbon spheres (HCSs) with... 

The treatment of water contaminated by bacteria is becoming a necessity. The nanomaterials possessing both intrinsic antibacterial properties and photocatalytic activity are excellent candidates for water disinfection. The powdered form of nanomaterials can be aggregated while embedding the nanomaterials into the NFs can overcome the limitation and enhance the photocatalytic activity and transition from UV-light to visiblelight. Here, graphene oxide (GO) was synthesized, grafted to chitosan, and decorated with silver nanoparticles (Ag NPs) to produce Ag-decorated reduced GO-graft-Chitosan (AGC) NPs. The blends of polyacrylonitrile (PAN) and AGC NPs were prepared in various concentrations of... 

Metal-organic frameworks (MOFs) biocompatible systems can host enzymes/bacteria/viruses. Herein we synthesized a series of fatty acid amide hydrolase (FAAH)-decorated UiO-66-NH2 based on Citrus tangerine leaf extract for drug delivery and biosensor applications. Five chemically manipulated FAAH-like benzamides were localized on the UiO-66-NH2 surface with physical interactions. Comprehensive cellular and molecular analyses were conducted on HEK-293, HeLa, HepG2, PC12, MCF-7, and HT-29 cell lines (cytotoxicity assessment after 24 and 48 h). MTT results proved above 95 and 50% relative cell viability in the absence and presence of the drug, respectively. A complete targeted drug-releasing... 

The solubility of Pd(NO3)2 in water is moderate whereas it is completely soluble in diluted HNO3 solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH2(Cr) were synthesized by aqueous solution of Pd(NO3)2 and Pd(NO3)2 solution in dilute HNO3 and used for CO oxidation reaction. The catalysts synthesized with Pd(NO3)2 solution in dilute HNO3 showed lower activity. The aqueous solution of Pd(NO3)2 was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd70Ni30/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd + Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution... 

Due to the widespread use of pesticides and their harmful effects on humans and wildlife, monitoring their residual amounts in crops is critically essential but still challenging regarding the development of high-throughput approaches. Herein, a colorimetric sensor array has been proposed for discrimination and identification of triazole fungicides using monometallic and bimetallic silver and gold nanoparticles. Aggregation-induced behavior of AgNPs, AuNPs, and Au-AgNPs in the presence of four triazole fungicides produced a fingerprint response pattern for each analyte. Innovative changes to the metal composition of nanoparticles leads to the production of entirely distinct response patterns... 

The demand and importance of fairness creams as a major cosmetic have increased significantly in recent years. However, some of these cosmetics contain heavy metals, hydroquinone and microorganism that can cause various health problems. Therefore, the aim of this study is to determine and examine the concentration of metals (i.e. Cd, Pb, Cr, Ni, Zn, Hg), hydroquinone and microorganisms in nine different fairness creams produced by local and international brands. The health risk assessment of the tested substances for consumers was accessed through systemic exposure dosage (SED), margin of safety (MoS), lifetime cancer risk (LCR), hazard quotient (HQ) and hazard index (HI). The concentration... 

In the current study, thin-film nanocomposite membranes (TFN-Mx) based on a zwitterion-functionalized metal-organic framework (MOF) have been developed for the forward osmosis (FO) salt-water separation process. The active polyamide layer was formed through the interfacial polymerization of the m-phenylenediamine aqueous phase (with or without the presence of MIL-125-NH-CC-Cys) and the trimesoyl chloride organic phase. In comparison with the results from the surface of the unmodified membrane, a nanofiller-incorporated TFN-M0.10 membrane represents a smoother and more wettable surface that collaborates synergically to enhance the membrane antifouling ability. Among the examined membranes,... 

Fundamental constraints imposing power-frequency trade-offs in conventional electronics have stimulated research on alternative technologies for millimeter-wave and sub-millimeter-wave applications. In this work, we use the picosecond threshold firing of nanoplasma switches to demonstrate on-chip millimeter-wave modulators that rely only on a single metal layer. We show amplitude shift keying (ASK) modulation with self-synthesized carrier frequencies up to 66 GHz (limited by the bandwidth of our experimental setup), with output powers up to 30 dBm. These all-metal nanoplasma modulators are low cost, and generally compatible with different platforms, from CMOS and III-V compounds to flexible... 

The present study evaluates the application of top-down steel demand estimation in developing countries. The anticipated steel demand for the case of Iran is calculated by three methods, including the growth model (GM), the intensity of use hypothesis (IUH), and the fixed stock paradigm (FCP). GM shows a broad range of apparent steel demand based on the assumed growth factor. When the gross domestic product (GDP) per capita reaches 13,000 dollars per person (constant 2010 US$), the IUH method estimates the consumption peak consumption at around 500 kg steel per capita per year, which is being expected between 2040 and 2060 depending on the economic growth assumptions. Since fluctuations in... 

A recyclable optical nanosensor was developed by immobilizing L-tyrosine functionalized silver nanoparticles (AgNPs) on the polyethylene terephthalate (PET) substrate for rapid determination of Pb2+ ions. At first, the L-tyrosine functionalized AgNPs were assessed in the solution phase; the response time was lower than 15 s, and a limit of detection lower than 9 nM was obtained in the dynamic range of 1–1000 nM. For fabrication of the optical assay kit, the design of experiment (DOE) was used to optimize the immobilization efficiency of the nanoparticles on PET films by studying AgNO3 concentration and pH as two crucial parameters. The assay kit in optimal conditions showed a sharp localized...