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Designing mitochondria-targeting phototheranostic agents (PTAs), which can simultaneously possess exceptional and balanced type-I photodynamic therapy (PDT) and photothermal therapy (PTT) performance, still remains challenging. Herein, benzene, furan, and thiophene were utilized as π bridges to develop multifunctional PTAs. STB with thiophene as a π bridge, in particular, benefiting from stronger donor-accepter (D-A) interactions, reduced the singlet-triplet energy gap (ΔE S1-T1 ), allowed more free intramolecular rotation, and exhibited outstanding near-infrared (NIR) emission, effective type-I reactive oxygen species (ROS) generation, and relatively high photothermal conversion efficiency (PCE) of 51.9%. In vitro and in vivo experiments demonstrated that positive-charged STB not only can actively target the mitochondria of tumor cells but also displayed strong antitumor effects and excellent in vivo imaging ability. This work subtly established a win-win strategy by π bridge engineering, breaking the barrier of making a balance between ROS generation and photothermal conversion, boosting a dual enhancement of PDT and PTT performance, and stimulating the development of multimodal imaging-guided precise cancer phototherapy.

Programmed cell death protein 1 (PD-1)/Programmed Cell Death Ligand 1 (PD-L1) blockade immunotherapy has emerged as a promising strategy to treat both solid and hematological malignancies. Despite the considerable therapeutic effects obtained in pre-clinical and clinical studies, PD-1/PD-L1 blockade therapy is still limited by the low benefit rates and a large number of patients still do not respond to this treatment. In this study, we developed a highly efficient and cancer-specific immunogenic cell death nanoinducer for effective tumor immunotherapy. A leukocyte membrane coated poly (lactic-co-glycolic acid) encapsulating glycyrrhetinic acid (GCMNPs) was developed to enhance targeting, tumor-homing capacity, and reduce toxicity in vivo. GCMNPs could induce ferroptosis in acute myeloid leukemia and colorectal cancer cells by downregulating glutathione-dependent peroxidases 4, leading to increased lipid peroxidation levels. Moreover, GCMNPs and ferumoxytol could synergistically enhance Fe-dependent cytotoxicity through the Fenton reaction. Finally, in vivo studies showed that GCMNPs synergized with ferumoxytol and anti-PD-L1 synergistically improve T-cell immune response against leukemia and colorectal tumor. This study anticipated that the combination of glycyrrhetinic acid-based nanomaterials and ferrotherapy would provide further insights into anti-cancer immune response to PD-1/PD-L1 blockade for both solid and hematological malignancies. STATEMENT OF SIGNIFICANCE: Despite the considerable therapeutic effects obtained in pre-clinical and clinical studies, PD-1/PD-L1 blockade therapy is still limited by the low benefit rates and a large number of patients still do not respond to this treatment. We designed a glycyrrhetinic acid-based nanoplatform as a new ICD inducer (GCMNPs), with high cancer cell specificity and reduced toxicity to AML and CRC. GCMNPs cooperates with ferumoxytol to promote a Fenton reaction and induce ferroptosis. Moreover, the combination of GCMNPs and ferumoxytol enhanced the blockage of PD-1/PD-L1 to activate T cells, subsequently generating a systemic immune response in CRC and AML mouse models. This pre-clinical findings provide the proof-of-concept of combination of glycyrrhetinic acid-based nanomaterials and ferrotherapy as an "ICD nano-inducer" and immunotherapeutic agent for treating cancer., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

The N6-methyladenosine (m 6 A) demethylase FTO plays an oncogenic role in acute myeloid leukemia (AML). Despite the promising recent progress for developing some small-molecule FTO inhibitors, the clinical potential remains limited due to mild biological function, toxic side effects and low sensitivity and/or specificity to leukemic stem cells (LSCs). Herein, FTO inhibitor-loaded GSH-bioimprinted nanocomposites (GNPIPP12MA) are developed that achieves targeting of the FTO/m 6 A pathway synergized GSH depletion for enhancing anti-leukemogenesis. GNPIPP12MA can selectively target leukemia blasts, especially LSCs, and induce ferroptosis by disrupting intracellular redox status. In addition, GNPIPP12MA increases global m 6 A RNA modification and decreases the transcript levels in LSCs. GNPIPP12MA augments the efficacy of the PD-L1 blockade by increasing the infiltration of cytotoxic T cells for enhanced anti-leukemia immunity. This study offers insights for a GSH-bioimprinted nanoplatform targeting m 6 A RNA methylation as a synergistic treatment strategy against cancer stem cells that may translate to clinical applications., (© 2022 Wiley-VCH GmbH.)

Hierarchical structures with sophisticated patterns allow the emergence of challenging properties. However, the highly cooperative and specific interactions needed for assembly spanning different length scales are typically lacking in inorganic nanoparticles (NPs). Here we show that size can be a common structural driving force for controlling hierarchical assembly of inorganic NPs into anisotropic superstructures. It involves first the self-limiting assembly of small CdS NPs into large supraparticles and their subsequent spontaneous organization into chains and tubules hundreds of nanometers long. Our quantitative calculations based on DLVO theory reveals an intrinsic size effect relating to the dimension change of assembly units in accordance with a negative cooperativity. It is shown that the size increase in building blocks creates an effective kinetic barrier contrast at different attachment sites due to the increase of interparticle electrostatic repulsion, switching the assembly from thermodynamically preferred 3D to kinetically favored 1D pathway. The size-encoded hierarchical assembly is accompanied by the ligand-controlled Oswald ripening process, which is responsible for the variation of hierarchical patterns from chains to tubules. The general principle in governing multistage inorganic NP ordering represents an important guideline toward the complex mesoscale structures that may surpass traditional materials in both design and functionality., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Cell-membrane-coated nanoparticles have emerged as a promising antitumor therapeutic strategy. However, the immunologic mechanism remains elusive, and there are still crucial issues to be addressed including tumor-homing capacity, immune incompatibility, and immunogenicity. Here, we reported a tumor-associated macrophage membrane (TAMM) derived from the primary tumor with unique antigen-homing affinity capacity and immune compatibility. TAMM could deplete the CSF1 secreted by tumor cells in the tumor microenvironment (TME), blocking the interaction between TAM and cancer cells. Especially, after coating TAMM to upconversion nanoparticle with conjugated photosensitizer (NPR@TAMM), NPR@TAMM-mediated photodynamic immunotherapy switched the activation of macrophages from an immunosuppressive M2-like phenotype to a more inflammatory M1-like state, induced immunogenic cell death, and consequently enhanced the antitumor immunity efficiency via activation of antigen-presenting cells to stimulate the production of tumor-specific effector T cells in metastatic tumors. This TAM-membrane-based photodynamic immunotherapy approach offers a new strategy for personalized tumor therapy.

Photothermal therapy (PTT) is an emerging therapeutic strategy in the treatment of cancer; however, a critical challenge remains in the rational design of synergistic nanoparticles as a potential photothermal transduction agent that can effectively enhance the therapeutic outcome of PTT for tumor ablation. Herein, we rationally designed, developed, and characterized hollow-structured CuS nanoparticles composited with carbon dots (CuSCDs), which demonstrated excellent photothermal conversion efficiency under a 808 nm laser irradiation with enhanced biocompatibility and reduced toxicity. Following coating with a macrophage membrane hybridized with T7 peptide on the surface of the proteasome inhibitor loaded CuSCD, CuSCDB@MMT7 exhibited targeted specificity to cancer cells with the characteristics of immunity escaping and enhanced transferrin receptor-mediated endocytosis. Predominantly, CuSCDB@MMT7-triggered PTT exhibited the accumulation of the polyubiquitinated tumor suppressor protein that is heat stabilized under NIR induced hyperthermia, facilitating augmented tumor cell apoptosis and the attenuated metastasis. This study provides a proof-of-concept for the proteasome inhibitor-loaded CuS/carbon dot nanocomposite-PTT strategy and highlights a promising therapeutic strategy for realizing enhanced therapeutic outcomes for effective clinical cancer therapy.

A stable nanoscaled single-excitation ratiometric luminescent pH sensor (MPDB-PCN) over a broad pH range from 2.5 to 8.6 is fabricated through post-synthetic modification of PCN-224 with naphthalimide-derived molecules. Due to the rapid, sensitive and linear response to pH, MPDB-PCN is capable of detecting 3-nitropropionic acid (3-NPA), an acid neurotoxin in food safety, with a low detection limit of 15 μM in sugarcane juice.

Tyrosine phosphorylation regulates the upstream signaling pathway but accounts for less than 0.1% of total phosphorylation in human cells. Herein, molecularly imprinted mesoporous materials were first synthesized to recognize the phosphorylated tyrosine residue from other phosphorylated residues.

Herein, sub-10 nm core-shell nanocrystals (NCs), which select Sr 2 LuF 7 :Yb/Er as core, Sr 2 GdF 7 as middle shell, and SrF 2 as an outermost shell, were synthesized by a seed-mediated growth process. The NCs possess good crystallinity, morphology, and up-conversion luminescent properties. After modification by polyethylenimine branched (PEI), in vitro cell up-conversion imaging with low autofluorescence was realized. Due to the presence of Gd 3+ ions, in vivo magnetic resonance (MR) imaging was also achieved with these designed NCs. More significantly, these special core-shell NCs exhibited high contrast in in vivo X-ray computed tomography (CT) imaging because of their good X-ray absorption ability. These results indicate that the core-shell up-conversion NCs can serve as promising contrast agents for up-conversion luminescence-MR-CT trimodal bioimaging.

The maghemite particulate nanosheets (MPNs) are prepared in solvothermal system by connecting the nanoparticles in two-dimension. The interconnected MPNs sustain a mesopores structure with a high accessible surface area of 164 m2/g, and have a high performance for Cr6+ adsorption. The Cr6+ removal process fit with Langmuir adsorption model with an adsorption capacity of 20.41 mg/g. The purified solution could reach a residual concentration of 0.002 mg/L for MPNs, which is much less than the concentration in the solution of 0.249 mg/L when the nanoparticles are used. The synthesized MPNs with a saturation magnetization of 70.51 emu/g at room temperature can be easily collected and separated by an external magnet in liquid. Exchange coupling and shape anisotropy are the main reason for the higher Ms of MPNs. The unique structure with large surface area and high saturation magnetization make the MPNs favourable for the application of magnetic separation.

Lanthanide-doped core-shell upconversion nanocrystals (UCNCs) have tremendous potential for applications in many fields, especially in bio-imaging and medical therapy. As core-shell UCNCs are mostly synthesized in organic solvents, tedious organic-aqueous phase transfer processes are usually needed for their use in bio-applications. Herein, we demonstrate the first example of one-step synthesis of highly luminescent core-shell UCNCs in the "aqueous" phase under mild conditions using innocuous reagents. A microwave-assisted approach allowed for layer-by-layer epitaxial growth of a hydrophilic NaGdF4 shell on NaYF4:Yb, Er cores. During this process, surface defects of the nanocrystals could be gradually passivated by the homogeneous shell deposition, resulting in obvious enhancement in the overall upconversion emission efficiency. In addition, the up-down conversion dual-mode luminescent NaYF4:Yb, Er@NaGdF4:Ce, Ln (Eu, Tb, Sm, Dy) nanocrystals were also synthesized to further validate the successful formation of the core-shell structure. More significantly, based on their superior solubility and stability in water solution, high upconversion efficiency and Gd-doped predominant X-ray absorption, the as-prepared NaYF4:Yb, Er@NaGdF4 core-shell UCNCs exhibited high contrast in in vitro cell imaging and in vivo X-ray computed tomography (CT) imaging, demonstrating great potential as multiplexed luminescent biolabels and CT contrast agents.

Monodisperse water-soluble hexagonal phase Ln(3+)-doped NaGdF(4) upconverting nanocrystals (UCNCs) have been successfully fabricated by means of a fast, facile, and environmentally friendly microwave-assisted route with polyethylenimine as the surfactant. Fine-tuning of the UC emission from visible to near-IR and finally to white light has been achieved. Furthermore, studies of the magnetic resonance imaging as well as the magnetization (magnetization-magnetic field curves) and the targeted recognition properties of FA-coupled amine-functionalized NaGdF(4)@SiO(2) UCNCs indicate that the obtained NaGdF(4) UCNCs can be potential candidates for dual-mode optical/magnetic bioapplications., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Water-dispersible Re(3+) doped CeF(3) colloidal nanocrystals with well controllable morphology and high crystallinity have been successfully synthesized through a solvothermal process. The TEM images illustrate that the Re(3+) doped CeF(3) nanocrystals are rectangular (or cubic) with a mean diameter of ~10 nm. The excellent dispersibility in some of the polar solvents including water is achieved by using polyethyleneimine as the capping agent. The amine groups of the polymer chains on one hand bind to the nanocrystal surface; on the other hand the free ones could link to functional materials including bio-molecules. The CeF(3) nanocrystals doped with Tb(3+) and Dy(3+) ions show the characteristic emission of Tb(3+ 5)D(4)-(7)F(J) (J = 6-3, with (5)D(4)-(7)F(5) green emission at 542 nm as the strongest one) and Dy(3+ 4)F(9/2)-(6)H(15/2) (blue-green color at 478 nm) and (4)F(9/2)-(6)H(13/2) (yellow color at 571 nm) transitions, respectively. The energy transfer from Ce(3+) to Tb(3+) and Dy(3+) was also investigated in detail. In vitro studies of Re(3+) doped CeF(3) colloidal nanocrystals on HepG2 cells confirm their excellent biological compatibility. The obtained solid CeF(3) : Tb(3+)/PDMS nanocomposites are very stable and flexible and exhibit strong green photoluminescence upon UV excitation., (This journal is © The Royal Society of Chemistry 2012)

Electrocatalytic CO2 reduction reaction (CO2RR) in acidic media is a promising approach to overcome the unavoidable formation of carbonates in alkaline or neutral electrolytes. However, the proton-rich environment near the catalyst surface favors hydrogen evolution reactions (HER), leading to lower energy efficiency of the desired products, especially in industrial-level current densities. Here, quaternary ammonium cationic surfactant (cetyltrimethylammonium bromide (CTAB)) was introduced into acidic electrolyte to modulate the interfacial microenvironment, which greatly enhanced CO2 electroreduction to formic acid (HCOOH) at the Bi/C nanoparticles electrode. Using a Bi/C nanoparticles electrode with CTAB added, constant production of formic acid was enabled with a cathodic energy efficiency of > 40% and maximum FEHCOOH (FE = Faradaic efficiency) of 86.2% at −400 mA·cm−2 over 24 h. Combined with in-situ attenuated total reflection Fourier transform infrared spectroscopy, the concentration of *OCHO intermediates significantly increased after CTAB modification, confirming that the hydrophobic interface microenvironment formed by dynamic adsorption of positively charged long alkyl chains on Bi/C nanoparticle electrodes inhibited HER and improved the selectivity of CO2RR to HCOOH. [ABSTRACT FROM AUTHOR]

Despite recent advances in targeted therapies and immunotherapies in acute myeloid leukemia, patient prognosis is still dismal given the high frequency of refractory cases or post‐remission relapse. Ferrotherapy, a novel anti‐cancer treatment strategy using iron‐based compounds, can mechanistically bypass the chemoresistance of cancer cells. However, cancer cells often overexpress the transmembrane iron exporter ferroportin that expels accumulated iron into the plasma, which can potentially limit the efficacy of ferrotherapy and lead to systemic toxic effects. Here, a ferro‐therapeutic nanoplatform is designed using fusing hepcidin and leukemia cell‐membrane vesicles on gold nanoparticles (AuNPs)‐loaded hollow mesoporous Prussian Blue (AuPB@LMHep). AuPB@LMHep specifically targeted leukemia cells through ferroportin and is subsequently internalized and disintegrated into iron and AuNPs through autophagy. The accumulation of iron due to blockade of ferroportin‐mediated iron efflux and the depletion of glutathione by the AuNPs triggered ferroptosis. Furthermore, iron accumulation inactivated the endogenous iron‐dependent m6A demethylase, thereby increasing global m6A RNA modification and suppressing multiple oncogenes. Finally, AuPB@LMHep enhanced the immune response to anti‐programmed death ligand1 treatment via increasing cytotoxic tumor‐infiltrating T cells. Pre‐clinical findings provide the proof‐of‐concept of hepcidin‐based nanocomposite as an "epigenetic drug" and immunotherapeutic agent for treating leukemia. [ABSTRACT FROM AUTHOR]

A novel zero-dimensional/two-dimensional CoP/black phosphorus heterostructure was successfully constructed by in situ growth of CoP nanoparticles on the surface of black phosphorus (BP) nanosheets through a facile solvothermal method. The as-prepared CoP/BP heterostructure exhibited excellent photocatalytic H2 production activity under visible- and near-infrared-light irradiation. The hydrogen evolution rate of the CoP/BP heterostructure was 694 mmolh-1g-1, which is about two times higher than that of the Pt/BP heterostructure. The in situ growth of CoP nanoparticles in black phosphorus nanosheets gives rise to excellent interfacial contact between the light-harvesting material and the co-catalysts, promotes fast charge transfer, and reduces charge recombination. Because the CoP nanoparticles are anchored on the surface of the BP nanosheets, agglomeration of the CoP nanoparticles is suppressed, and thus, the high surface area and large number of active sites are effectively maintained. [ABSTRACT FROM AUTHOR]

Abstract: Amorphous materials exhibit distinct physical and chemical properties compared to crystalline or quasi‐crystalline phases, because of their unique atomic arrangements of short‐range order but long‐range disorder. Designing a nanocomposite that contains both crystalline and amorphous phases is a valid approach to fully exploit the effects of each component. In this work, a nanocomposite consisting of crystalline Ag2S nanoparticles embedded in an amorphous Cu2S matrix (Ag2S/a‐Cu2S) is synthesized by a facile one‐pot solvothermal method. This process is achieved by diffusing silver into crystalline Cu2S. The silver is able to diffuse into Cu2S and form crystalline Ag2S nanoparticles inside them, while the crystalline Cu2S is converted into an amorphous phase owing to the silver diffusion. Furthermore, the introduction of nanoscale Ag2S particles into Cu2S improve electrical conductivity. This design of amorphous matrix containing nanocrystalline particles may open up new strategies for the transition from crystalline to amorphous phases of semiconductors. [ABSTRACT FROM AUTHOR]

Controlled crystallization is very important for crystal growth. The electrospray (ES) technique has attracted great interest thanks to its advantages of facile manipulation of micrometer droplets and the generation of fine and charged droplets with very narrow size dispersion. In this work, nanocrystals with cubic shapes with 32 nm edges were successfully grown from ultra-dilute NaCl solution (1 µg mL-1) on a millisecond timescale by an ES technique. Dispersed and charged microdroplets were created by ES. In the process, an increase in ion strength and built-in electric field in microdroplets promoted nucleation and growth. Moreover, solvent evaporation increased solute and charge concentration and decreased the size of the microdroplets, which had a further effect on nucleation and growth. The morphologies of crystals were the competitive results of ion strength and evaporation. Fortunately, these physicochemical properties can be controlled facilely by adjusting the ES parameters. This report suggests potential application of ES technology for controllable crystallization of pharmaceuticals, proteins, etc. [ABSTRACT FROM AUTHOR]

The morphology of CuInSe2 nanocrystals plays a key role in their functional properties. Achieving controllable morphology is significant for studying their structures and novel properties. Here, CuInSe2 nanocrystals with a trigonal-pyramidal shape have successfully been synthesized by a facile solution-phase method. The nanocrystals were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), etc. The morphological evolution of the CuInSe2 nanocrystals was illustrated by tuning the injection temperature of oleylamine-selenium (OAm-Se). In addition, CuInSe2 nanocrystals with spherical and ellipsoidal shapes were also obtained when copper stearate was used as the copper precursor. [ABSTRACT FROM AUTHOR]

BiVO nanoparticles are prepared by molten salt method. Tetragonal BiVO completely transforms to monoclinic phase after heating in molten LiNO at 270 °C for 18 h. The average particle sizes of monoclinic BiVO varied from 30 to 52 nm while the initial ratio of BiVO to LiNO changes from 1:6 to 1:24. The photocatalytic activity is evaluated by measuring decolorization of N, N, N′, N′-tetraethylated rhodamine dye solution under visible-light irradiation. Both of the de-ethylation and chromophore cleavage are responsible for the decolorization of RB. The sample with an average particle size of 52 nm and a moderate surface area of 10 m/g exhibit the highest visible-light photocatalytic activity. The shift of Raman peak position indicates that the symmetry distortions in the local structure of the monoclinic BiVO. The variations of the local structure result in the modification of the electronic structure, which is responsible for the high visible-light photocatalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Homogeneous porous CoP nanoparticles are prepared by a facile templating strategy. • The porous CoP nanoparticle composite reveals improved catalytic activity and stability towards OER. • The porous CoP nanoparticle exhibits superior OER activity than commercial RuO 2. • This strategy would be helpful for the development of other materials for electrochemical applications. The realization of hydrogen generation through industrial electrochemical water splitting is largely prohibited by oxygen evolution reaction (OER) owing to its intrinsically sluggish kinetics. Therefore, the development of highly efficient OER electrocatalysts is of great significance. Recently, various composites with porous nanostructures and superior catalytic ability for different electrochemical applications have been fabricated based on zeolitic imidazolate frameworks (ZIFs), and transition metal phosphides (TMPs) have been reported to be one of the most promising electrocatalysts for OER. Herein, in this work, we designed the porous CoP nanoparticles (P-CoP-NPs) composite as an effective catalyst for OER via a facile templating strategy using polystyrene (PS) spheres as the template and ZIF-67 as the cobalt source. The obtained P-CoP-NPs composite largely improved the OER catalytic performance. Such optimized P-CoP-NPs catalyst required an overpotential of 320 mV to achieve the current density of 10 mA cm−2 in alkaline solution. P-CoP-NPs catalyst still exhibited superior catalytic stability after continuous water oxidation process with negligible decay in potential, indicating its potential to be a high-performance OER electrocatalyst. The strategy used in this study makes it possible to design and synthesize low-cost electrocatalysts with earth-abundant elements for water splitting in practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Y3−x−y Ce x Gd y Fe5O12 (x =0–0.1, y =0–1.0) nanoparticles were fabricated by a sol–gel method. The crystalline structures and magnetic properties of samples were investigated by X-ray diffraction (XRD), scanning probe microscopy (SPM), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometer (VSM). The XRD patterns of Y3−x−y Ce x Gd y Fe5O12 have only peaks of the garnet structure and the mean size range from 42 to 65nm. The particle''s size observed for all the samples analyzed by SPM are in good agreement with these data from XRD. The particle''s size ranged from 50 to 70nm, at the same time, there are small amount of reunited particles can be observed. XPS for Y2.9Ce0.1Fe5O12 gives two peaks at 885.15 and 905.15eV attributing to Ce3+3d5/2 and 3d3/2, respectively. The results confirm the valence state of Ce atoms being +3. Results of VSM show that the saturation magnetization is increased with increasing Ce content (x) and is decreased with increasing the Gd concentration (y) in a linear manner. The saturation magnetization is increased with increasing the particle''s size. [Copyright &y& Elsevier]

Abstract: Mössbauer spectra and magnetic measurement of Ni0.7Mn0.3Gd0.1Fe1.9O4 ferrite were investigated by Oxford MS-500 Mössbauer spectrometer and superconducting quantum interference device (SQUID) magnetometer with a field 5T. Ni0.7Mn0.3Gd0.1Fe1.9O4 nanoparticles have a considerable coercivity of 1040Oe when the test temperature is reduced to 2K. Mössbauer spectra show that Ni0.7Mn0.3Gd0.1Fe1.9O4 nanoparticles exhibit superparamagnetism at room temperature and ferrimagnetism at 77K. [Copyright &y& Elsevier]

Abstract: Dy3+-substituted garnet nanoparticles Y3− x Dy x Fe5O12 (, 0.2, 0.4, 0.6, 0.8 and 1.0) were fabricated by a sol–gel method and their crystalline structures and magnetic properties were investigated by using X-ray diffraction (XRD), infrared spectroscopy and vibrating sample magnetometer (VSM). The XRD patterns of Y3− x Dy x Fe5O12 have only peaks of the garnet structure and the sizes of particles range from 37 to 63nm. Results of VSM show that the saturation magnetization of Y3− x Dy x Fe5O12 () particles is not only obviously less than pure Yttrium iron garnet, but also decreases with increasing the Dy concentration (x) in a linear manner. Meanwhile, it is observed that with the enhancement of the surface spin effects, the saturation magnetization rises as the particle size is increased. [Copyright &y& Elsevier]

Abstract: (Y,Gd)BO3:Eu powders were prepared by conventional solid-reaction method. Surface-modified (Y,Gd)BO3:Eu powders with MgF2 were prepared by the emulsion method. The best preparing way is that MgCl2 was dropped to the mixture of NH4F and (Y,Gd)BO3:Eu powders to prepare surface-modified (Y,Gd)BO3:Eu powders. The interaction between F− ions and the phosphor particles was discussed. It is shown that the structures of surface-modified (Y,Gd)BO3:Eu powders were measured by XRD. The luminescent properties of (Y,Gd)BO3:Eu powders with MgF2 are researched. [Copyright &y& Elsevier]

Abstract: The effects of rare-earth ions with different radii and magnetic moments on the magnetic properties of Ni–Mn ferrite are investigated. X-ray diffraction pattern has shown the presence of cubic structure of spinel ferrite for all samples. The values of M s and H c are decreasing with increasing of testing temperatures for all samples. The H c value of Ni0.7Mn0.3La0.1Fe1.9O4 reaches 1082Oe at 2K. Mössbauer spectra tested at 273K indicate the presence of superparamagnetism for samples calcined at 873K. [Copyright &y& Elsevier]

Abstract: Gd x BiY2−x Fe5O12 (x =0, 0.1, 0.2, 0.4, 0.6, 0.8) nanocrystals were synthesized by sol–gel method. Samples were characterized by using of X-ray diffraction (XRD), thermal gravity analysis (TGA), differential thermal analysis (DTA), transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM).The average size of the particles was calculated by Scherrer''s formula from XRD data, which are from 43 to 50 nm. The effect of Gd3+ substitution for Y3+ on magnetic properties of BiY2Fe5O12 has been investigated. [Copyright &y& Elsevier]

Abstract: Gd3+-substituted garnet nanoparticles Y3− x Gd x Fe5O12 (, 0.2, 0.4, 0.6, 0.8 and 1.0) were fabricated by a sol–gel method and their crystalline structures and magnetic properties were investigated by using X-ray diffraction (XRD), IR spectroscopy and vibrating sample magnetometer (VSM). The XRD patterns of Y3− x Gd x Fe5O12 have only peaks of the garnet structure and the sizes of particles range from 34 to 67nm. Results of VSM show that the special saturation magnetization of Y3− x Gd x Fe5O12 () particles are not only obviously less than pure YIG, but also decrease with increasing Gd concentration (x) in a linear manner. Meanwhile, it is observed that with the enhancement of the surface spin effects, the saturation magnetization rises as the particle size is increased. [Copyright &y& Elsevier]

Abstract: Nanocrystalline Ni0.7Mn0.3Gd x Fe2−x O4 ferrites were prepared by the emulsion method. The growth of particles, the structure and the magnetic properties were investigated by X-ray diffraction (XRD), Mössbauer spectroscopy and vibrating sample magnetometer (VSM). Furthermore, the influence of Gd2O3 on magnetic properties of Ni–Mn ferrite powders has been investigated in detail. When the crystallite sizes are about 30–40 nm, all the samples have similar Ms values. The variational rules of saturation magnetization (Ms) and coercivity (Hc) along with doped Gd contents at different sintering temperatures show that the maximum Gd ions content doped into ferrite lattices is x =0.06. When Gd-doped content x is larger than 0.06, the doped Gd ions cannot enter into the ferrite lattice totally but reside at grain boundary, as the ionic radii of the Gd3+ ions are larger than that of Fe3+ ions. The ferrimagnetism has not disappeared completely, even if the crystallite size is 7.8 nm. [Copyright &y& Elsevier]

Nanocrystalline Ni0.7Mn0.3NdxFe2–xO4 ferrites with x values ranging from 0.00 to 0.10, in step of 0.02, have been prepared by the emulsion method. The structure and the morphology of ferrite nanoparticles were measured using X-ray diffractometer (XRD), transmission electron microscope (TEM) and Mössbauer spectra. It is shown that the structure of Ni0.7Mn0.3NdxFe2–xO4 ferrites nanoparticles is single spinel structure. The average crystallite sizes of the samples calculated using Scherrer'' relationship are almost identical with the observed diameter from the image of TEM. The magnetic properties of the samples were tested by a vibrating sample magnetometer (VSM) at room temperature. The nanoparticles of the samples have superparamagnetism when particle sizes are about 10 nm. [Copyright &y& Elsevier]

Nanoparticles of Al-doped SnO2 have been hydrothermally synthesized. The influences of the hydrothermal reaction time, the molar ratio of Sn/Al as well as the pH value of the solution have been studied. During the hydrothermal synthesis, the particle’s core is rich in Sn and the surface is rich in Al. The Al-rich surface prevents the particles from further growing up either in the hydrothermal condition or during the calcination at 600 °C for a short period of time. The optimal hydrothermal synthesis condition of the nanoparticles is pH 5, Sn/Al=4:1 and 12 h at 160 °C. The products have been studied by XRD, TEM and 27Al solid-state NMR. [Copyright &y& Elsevier]

Nanocrystalline Ni0.7Mn0.3NdxFe2−xO4 ferrites (Nd2O3-doped Ni–Mn ferrites) have been prepared by the emulsion method. The structure and the morphology of the ferrite nanoparticles were measured by using X-ray diffractometer (XRD), Differential thermal analysis (DTA) and thermal gravity (TG). It is shown that the structure of Ni0.7Mn0.3NdxFe2−xO4 ferrite nanoparticles is single spinel structure. The average crystalline sizes of the samples are from 7.0 to 62.3 nm. The magnetic properties of samples were tested at room temperature by using a Vibrating Sample Magnetometer (VSM). The nanoparticles of the samples have superparamagnetisim which particle sizes are about 10 nm. [Copyright &y& Elsevier]

The self-assemble propensity of the controlled shape and size distribution titania nanoparticles makes the particles oriented organization to ordered structures without substrate by a hydrolysis-hydrothermal route. The procedure offers the possibility of a generalized approach to the production of patterned organization of single and complex oxide nanoparticles with size and morphology tunable. [Copyright &y& Elsevier]