Lead-Free Relaxor Ferroelectric Ceramics with Ultrahigh Energy Storage Densities via Polymorphic Polar Nanoregions Design.

One of the long-standing challenges of current lead-free energy storage ceramics for capacitors is how to improve their comprehensive energy storage properties effectively, that is, to achieve a synergistic improvement in the breakdown strength (Eb ) and the difference between maximum polarization (Pmax ) and remnant polarization (Pr ), making them comparable to those of lead-based capacitor materials. Here, a polymorphic polar nanoregions (PNRs) structural design by first introducing 0.06 mol BaTiO3 into Bi0.5 Na0.5 TiO3 is proposed to construct the morphotropic phase boundary with coexisting structures of micrometer-size domains and polymorphic nanodomains, enhance the electric field-induced polarization response (increase Pmax ). Then Sr(Al0.5 Ta0.5 )O3 (SAT)-doped 0.94 Bi0.5 Na0.5 TiO3 -0.06BaTiO3 (BNBT) energy storage ceramics with polymorphic PNRs structures are synthesized following the guidance of phase-field simulation and rational composition design (decrease Pr ). Finally, a large recoverable energy density (Wrec ) of 8.33 J cm-3 and a high energy efficiency (η) of 90.8% under 555 kV cm-1 are obtained in the 0.85BNBT-0.15SAT ceramic prepared by repeated rolling process method (enhance Eb ), superior to most practical lead-free competitors increased consideration of the stability of temperature (a variation <±6.2%) and frequency (Wrec > 5.0  cm-3 , η > 90%) at 400 kV cm-1 . This strategy provides a new conception for the design of other-based multifunctional energy storage dielectrics.

Perspectives on Working Voltage of Aqueous Supercapacitors.

Aqueous supercapacitors have the superiorities of high safety, environmental friendliness, inexpensive, etc. High energy density supercapacitors are not conducive to manufacturing due to the limitation of water thermodynamic decomposition potential, resulting in a narrow working voltage window. To address such challenges, a great endeavor has started to investigate high voltage aqueous supercapacitors as well as making some progress. This review summarizes key strategies regarding the realization of wide working voltage of aqueous supercapacitors and analyzes the involved mechanism, including the optimization of electrodes, electrolytes, diaphragms, and supercapacitor structures. From the perspective of extending the theoretical voltage window, electrode functionalization, heteroatom doping, neutral electrolyte, water-in-salt electrolyte, introducing redox mediators into electrolyte, and designing asymmetric structure are effective strategies for achieving this goal. Further, the actual voltage window can be maximized by optimizing the electrode mass ratio, adjusting potential of zero voltage, and electrode functionalization. The challenge and future of expanding working voltage of aqueous supercapacitors are further discussed. Importantly, this review provides inspiration for the development of supercapacitors with high energy density.

Phase Evolution in the CaZrTi2O7-Dy2Ti2O7 System: A Potential Host Phase for Minor Actinide Immobilization.

Zirconolite is considered to be a suitable wasteform material for the immobilization of Pu and other minor actinide species produced through advanced nuclear separations. Here, we present a comprehensive investigation of Dy3+ incorporation within the self-charge balancing zirconolite Ca1-xZr1-xDy2xTi2O7 solid solution, with the view to simulate trivalent minor actinide immobilization. Compositions in the substitution range 0.10 ≤ x ≤ 1.00 (Δx = 0.10) were fabricated by a conventional mixed oxide synthesis, with a two-step sintering regime at 1400 °C in air for 48 h. Three distinct coexisting phase fields were identified, with single-phase zirconolite-2M identified only for x = 0.10. A structural transformation from zirconolite-2M to zirconolite-4M occurred in the range 0.20 ≤ x ≤ 0.30, while a mixed-phase assemblage of zirconolite-4M and cubic pyrochlore was evident at Dy concentrations 0.40 ≤ x ≤ 0.50. Compositions for which x ≥ 0.60 were consistent with single-phase pyrochlore. The formation of zirconolite-4M and pyrochlore polytype phases, with increasing Dy content, was confirmed by high-resolution transmission electron microscopy, coupled with selected area electron diffraction. Analysis of the Dy L3-edge XANES region confirmed that Dy was present uniformly as Dy3+, remaining analogous to Am3+. Fitting of the EXAFS region was consistent with Dy3+ cations distributed across both Ca2+ and Zr4+ sites in both zirconolite-2M and 4M, in agreement with the targeted self-compensating substitution scheme, whereas Dy3+ was 8-fold coordinated in the pyrochlore structure. The observed phase fields were contextualized within the existing literature, demonstrating that phase transitions in CaZrTi2O7-REE3+Ti2O7 binary solid solutions are fundamentally controlled by the ratio of ionic radius of REE3+ cations.

Chemical state mapping of simulant Chernobyl lava-like fuel containing material using micro-focused synchrotron X-ray spectroscopy.

Uranium speciation and redox behaviour is of critical importance in the nuclear fuel cycle. X-ray absorption near-edge spectroscopy (XANES) is commonly used to probe the oxidation state and speciation of uranium, and other elements, at the macroscopic and microscopic scale, within nuclear materials. Two-dimensional (2D) speciation maps, derived from microfocus X-ray fluorescence and XANES data, provide essential information on the spatial variation and gradients of the oxidation state of redox active elements such as uranium. In the present work, we elaborate and evaluate approaches to the construction of 2D speciation maps, in an effort to maximize sensitivity to the U oxidation state at the U L3-edge, applied to a suite of synthetic Chernobyl lava specimens. Our analysis shows that calibration of speciation maps can be improved by determination of the normalized X-ray absorption at excitation energies selected to maximize oxidation state contrast. The maps are calibrated to the normalized absorption of U L3 XANES spectra of relevant reference compounds, modelled using a combination of arctangent and pseudo-Voigt functions (to represent the photoelectric absorption and multiple-scattering contributions). We validate this approach by microfocus X-ray diffraction and XANES analysis of points of interest, which afford average U oxidation states in excellent agreement with those estimated from the chemical state maps. This simple and easy-to-implement approach is general and transferrable, and will assist in the future analysis of real lava-like fuel-containing materials to understand their environmental degradation, which is a source of radioactive dust production within the Chernobyl shelter.

Characterization of and Structural Insight into Struvite-K, MgKPO4·6H2O, an Analogue of Struvite.

Struvite-K (MgKPO4·6H2O) is a magnesium potassium phosphate mineral with naturally cementitious properties, which is finding increasing usage as an inorganic cement for niche applications including nuclear waste management and rapid road repair. Struvite-K is also of interest in sustainable phosphate recovery from wastewater and, as such, a detailed knowledge of the crystal chemistry and high-temperature behavior is required to support further laboratory investigations and industrial applications. In this study, the local chemical environments of synthetic struvite-K were investigated using high-field solid-state 25Mg and 39K MAS NMR techniques, alongside 31P MAS NMR and thermal analysis. A single resonance was present in each of the 25Mg and 39K MAS NMR spectra, reported here for the first time alongside the experimental and calculated isotropic chemical shifts, which were comparable to the available data for isostructural struvite (MgNH4PO4·6H2O). An in situ high-temperature XRD analysis of struvite-K revealed the presence of a crystalline-amorphous-crystalline transition that occurred between 30 and 350 °C, following the single dehydration step of struvite-K. Between 50 and 300 °C, struvite-K dehydration yielded a transient disordered (amorphous) phase identified here for the first time, denoted δ-MgKPO4. At 350 °C, recrystallization was observed, yielding ß-MgKPO4, commensurate with an endothermic DTA event. A subsequent phase transition to γ-MgKPO4 was observed on further heating, which reversed on cooling, resulting in the α-MgKPO4 structure stabilized at room temperature. This behavior was dissimilar from that of struvite exposed to high temperature, where NH4 liberation occurs at temperatures >50 °C, indicating that struvite-K could potentially withstand high temperatures via a transition to MgKPO4.

Low-Temperature Nitridation of Fe3O4 by Reaction with NaNH2.

Low-temperature soft chemical synthesis routes to transition-metal nitrides are of interest as an alternative to conventional high-temperature ammonolysis reactions involving large volumes of chemotoxic NH3 gas. One such method is the reaction between metal oxides and NaNH2 at ca. 200 °C to yield the counterpart nitrides; however, there remains uncertainty regarding the reaction mechanism and product phase assemblage (in particular, noncrystalline components). Here, we extend the chemical tool box and mechanistic understanding of such reactions, demonstrating the nitridation of Fe3O4 by reaction with NaNH2 at 170-190 °C, via a pseudomorphic reaction. The more reduced Fe3O4 precursor enabled nitride formation at lower temperatures than the previously reported equivalent reaction with Fe2O3. The product phase assemblage, characterized by X-ray diffraction, thermogravimetric analysis, and 57Fe Mössbauer spectroscopy, comprised 49-59 mol % ε-Fe2+xN, accompanied by 29-39 mol % FeO1-xNx and 8-14 mol % γ″-FeN. The oxynitride phase was apparently noncrystalline in the recovered product but could be crystallized by heating at 180 °C. Although synthesis of transition-metal nitrides is achieved by reaction of the counterpart oxide with NaNH2, it is evident from this investigation that the product phase assemblage may be complex, which could prove a limitation if the objective is to produce a single-phase product with well-defined electrical, magnetic, or other physical properties for applications. However, the significant yield of the FeO1-xNx oxynitride phase identified in this study opens the possibility for the synthesis of metastable oxynitride phases in high yield, by reaction of a metal oxide substrate with NaNH2, with either careful control of H2O concentration in the system or postsynthetic hydrolysis and crystallization.

Synergy of nanodiamond-doxorubicin conjugates and PD-L1 blockade effectively turns tumor-associated macrophages against tumor cells.

BACKGROUND: Tumor-associated macrophages (TAMs) are the most abundant stromal cells in the tumor microenvironment. Turning the TAMs against their host tumor cells is an intriguing therapeutic strategy particularly attractive for patients with immunologically "cold" tumors. This concept was mechanistically demonstrated on in vitro human and murine lung cancer cells and their corresponding TAM models through combinatorial use of nanodiamond-doxorubicin conjugates (Nano-DOX) and a PD-L1 blocking agent BMS-1. Nano-DOX are an agent previously proved to be able to stimulate tumor cells' immunogenicity and thereby reactivate the TAMs into the anti-tumor M1 phenotype. RESULTS: Nano-DOX were first shown to stimulate the tumor cells and the TAMs to release the cytokine HMGB1 which, regardless of its source, acted through the RAGE/NF-κB pathway to induce PD-L1 in the tumor cells and PD-L1/PD-1 in the TAMs. Interestingly, Nano-DOX also induced NF-κB-dependent RAGE expression in the tumor cells and thus reinforced HMGB1's action thereon. Then, BMS-1 was shown to enhance Nano-DOX-stimulated M1-type activation of TAMs both by blocking Nano-DOX-induced PD-L1 in the TAMs and by blocking tumor cell PD-L1 ligation with TAM PD-1. The TAMs with enhanced M1-type repolarization both killed the tumor cells and suppressed their growth. BMS-1 could also potentiate Nano-DOX's action to suppress tumor cell growth via blocking of Nano-DOX-induced PD-L1 therein. Finally, Nano-DOX and BMS-1 achieved synergistic therapeutic efficacy against in vivo tumor grafts in a TAM-dependent manner. CONCLUSIONS: PD-L1/PD-1 upregulation mediated by autocrine and paracrine activation of the HMGB1/RAGE/NF-κB signaling is a key response of lung cancer cells and their TAMs to stress, which can be induced by Nano-DOX. Blockade of Nano-DOX-induced PD-L1, both in the cancer cells and the TAMs, achieves enhanced activation of TAM-mediated anti-tumor response.

Properties and microstructure of basic magnesium sulfate cement: Influence of silica fume.

Silica fume (SF) as an important supplementary cementitious material has been widely used in Portland cement, but few published articles have reported on the effect of SF on the performance and hydration mechanism of basic magnesium sulfate cement (BMSC). In the present work, the properties, microstructure and hydration mechanism of BMSC influenced by SF was studied systematically. The results show that the setting time and compressive strength of BMSC may increase with the increase of SF content, while the hydration heat will decrease with the increase of SF content. Mercury intrusion porosimetry (MIP), X-ray computed tomography (X-CT), scanning electron microscope- Energy dispersive spectrometer (SEM-EDS) results show that SF exhibits filling effect in the BMSC matrix, which makes the microstructure of BMSC matrix with SF more compact. In addition, solid-state magnetic resonance (NMR) and SEM-EDS analysis indicate that the activity of SF was excited in the BMSC matrix, resulting in the formation of M-S-H gel.

Crystal and Electronic Structures of A2NaIO6 Periodate Double Perovskites (A = Sr, Ca, Ba): Candidate Wasteforms for I-129 Immobilization.

The synthesis, structure, and thermal stability of the periodate double perovskites A2NaIO6 (A= Ba, Sr, Ca) were investigated in the context of potential application for the immobilization of radioiodine. A combination of X-ray diffraction and neutron diffraction, Raman spectroscopy, and DFT simulations were applied to determine accurate crystal structures of these compounds and understand their relative stability. The compounds were found to exhibit rock-salt ordering of Na and I on the perovskite B-site; Ba2NaIO6 was found to adopt the Fm-3m aristotype structure, whereas Sr2NaIO6 and Ca2NaIO6 adopt the P21/n hettotype structure, characterized by cooperative octahedral tilting. DFT simulations determined the Fm-3m and P21/n structures of Ba2NaIO6 to be energetically degenerate at room temperature, whereas diffraction and spectroscopy data evidence only the presence of the Fm-3m phase at room temperature, which may imply an incipient phase transition for this compound. The periodate double perovskites were found to exhibit remarkable thermal stability, with Ba2NaIO6 only decomposing above 1050 °C in air, which is apparently the highest recorded decomposition temperature so far recorded for any iodine bearing compound. As such, these compounds offer some potential for application in the immobilization of iodine-129, from nuclear fuel reprocessing, with an iodine incorporation rate of 25-40 wt%. The synthesis of these compounds, elaborated here, is also compatible with both current conventional and future advanced processes for iodine recovery from the dissolver off-gas.

Optimization of Magnesium Potassium Phosphate Cements Using Ultrafine Fly Ash and Fly Ash.

The effect of ultrafine fly ash (UFA) and fly ash (FA) on the physical properties, phase assemblage, and microstructure of magnesium potassium phosphate cement (MKPC) was investigated. This study revealed that the UFA addition does not affect the calorimetry hydration peak associated with MKPC formation when normalized to the reactive components (MgO and KH2PO4). However, there is an indication that greater UFA additions lead to an increased reaction duration, suggesting the potential formation of secondary reaction products. The addition of a UFA:FA blend can delay the hydration and the setting time of MKPC, enhancing workability. MgKPO4·6H2O was the main crystalline phase observed in all systems; however, at low replacement levels in the UFA-only system (<30 wt %), Mg2KH(PO4)2·15H2O was also observed by XRD, SEM/EDS, TGA, and NMR (31P MAS, 1H-31P CP MAS). Detailed SEM/EDS and MAS NMR investigations (27Al, 29Si, 31P) demonstrated that the role of UFA and UFA:FA was mainly as a filler and diluent. Overall, the optimized formulation was determined to contain 40 wt % fly ash (10 wt % UFA and 30 wt % FA (U10F30)), which achieved the highest compressive strength and fluidity and produced a dense microstructure.

Crystal chemical design, synthesis and characterisation of U(IV)-dominant betafite phases for actinide immobilisation.

Crystal chemical design principles were applied to synthesise novel U4+ dominant and titanium excess betafite phases Ca1.15(5)U0.56(4)Zr0.17(2)Ti2.19(2)O7 and Ca1.10(4)U0.68(4)Zr0.15(3)Ti2.12(2)O7, in high yield (85-95 wt%), and ceramic density reaching 99% of theoretical. Substitution of Ti on the A-site of the pyrochlore structure, in excess of full B-site occupancy, enabled the radius ratio (rA/rB = 1.69) to be tuned into the pyrochlore stability field, approximately 1.48 ≲ rA/rB ≲ 1.78, in contrast to the archetype composition CaUTi2O7 (rA/rB = 1.75). U L3-edge XANES and U 4f7/2 and U 4f5/2 XPS data evidenced U4+ as the dominant speciation, consistent with the determined chemical compositions. The new betafite phases, and further analysis reported herein, point to a wider family of actinide betafite pyrochlores that could be stabilised by application of the underlying crystal chemical principle applied here.

Underpinning the use of indium as a neutron absorbing additive in zirconolite by X-ray absorption spectroscopy.

Indium (In) is a neutron absorbing additive that could feasibly be used to mitigate criticality in ceramic wasteforms containing Pu in the immobilised form, for which zirconolite (nominally CaZrTi2O7) is a candidate host phase. Herein, the solid solutions Ca1-xZr1-xIn2xTi2O7 (0.10 ≤ x ≤ 1.00; air synthesis) and Ca1-xUxZrTi2-2xIn2xO7 (x = 0.05, 0.10; air and argon synthesis) were investigated by conventional solid state sintering at a temperature of 1350 °C maintained for 20 h, with a view to characterise In3+ substitution behaviour in the zirconolite phase across the Ca2+, Zr4+ and Ti4+ sites. When targeting Ca1-xZr1-xIn2xTi2O7, single phase zirconolite-2M was formed at In concentrations of 0.10 ≤ x ≤ 0.20; beyond x ≥ 0.20, a number of secondary In-containing phases were stabilised. Zirconolite-2M remained a constituent of the phase assemblage up to a concentration of x = 0.80, albeit at relatively low concentration beyond x ≥ 0.40. It was not possible to synthesise the In2Ti2O7 end member compound using a solid state route. Analysis of the In K-edge XANES spectra in the single phase zirconolite-2M compounds confirmed that the In inventory was speciated as trivalent In3+, consistent with targeted oxidation state. However, fitting of the EXAFS region using the zirconolite-2M structural model was consistent with In3+ cations accommodated within the Ti4+ site, contrary to the targeted substitution scheme. When deploying U as a surrogate for immobilised Pu in the Ca1-xUxZrTi2-2xIn2xO7 solid solution, it was demonstrated that, for both x = 0.05 and 0.10, In3+ was successfully able to stabilise zirconolite-2M when U was distributed predominantly as both U4+ and average U5+, when synthesised under argon and air, respectively, determined by U L3-edge XANES analysis.

Bottom-up synthesis of 2D layered high-entropy transition metal hydroxides.

Low-dimensional high-entropy materials, such as nanoparticles and two-dimensional (2D) layers, have great potential for catalysis and energy applications. However, it is still challenging to synthesize 2D layered high-entropy materials through a bottom-up soft chemistry method, due to the difficulty of mixing and assembling multiple elements in 2D layers. Here, we report a simple polyol process for the synthesis of a series of 2D layered high-entropy transition metal (Co, Cr, Fe, Mn, Ni, and Zn) hydroxides (HEHs), involving the hydrolysis and inorganic polymerization of metal-containing species in ethylene glycol media. The as-synthesized HEHs demonstrate 2D layered structures with interlayer distances ranging from 0.860 to 0.987 nm and homogeneous elemental distribution of designed equimolar stoichiometry in the layers. These 2D HEHs exhibit a low overpotential of 275 mV at 10 mA cm-2 in a 0.1 M KOH electrolyte for the oxygen evolution reaction. Superparamagnetic spinel-type high-entropy nanoparticles can also be obtained by annealing these HEHs. Our polyol approach creates opportunities for synthesizing low-dimensional high-entropy materials with promising properties and applications.

Correction: Engineering lithiophilic Ni-Al@LDH interlayers on a garnet-type electrolyte for solid-state lithium metal batteries.

Correction for 'Engineering lithiophilic Ni-Al@LDH interlayers on a garnet-type electrolyte for solid-state lithium metal batteries' by Wei Liu et al., Chem. Commun., 2021, 57, 10214-10217, DOI: 10.1039/D1CC02932K.

Design of a Sub-6 GHz Dielectric Resonator Antenna with Novel Temperature-Stabilized (Sm1-xBix)NbO4 (x = 0-0.15) Microwave Dielectric Ceramics.

Microwave dielectric ceramics exhibiting a low dielectric constant (εr), high quality factor (Q × f), and thermal stability, specifically in an ultrawide temperature range (from -40 to +120 °C), have attracted much attention. In addition, the development of 5G communication has caused an urgent demand for electronic devices, such as dielectric resonant antennas. Hence, the feasibility of optimizing the dielectric properties of the SmNbO4 (SN) ceramics by substituting Bi3+ ions at the A site was studied. The permittivity principally hinges on the contribution of Sm/Bi-O to phonon absorption in the microwave range, while the reduced sintering temperature results in a smaller grain size and slightly lower Q × f value. The expanded and distorted crystal cell indicates that Bi3+ doping effectively regulates the temperature coefficient of resonant frequency (TCF) by adjusting the strains (causing the distorted monoclinic structure) of monoclinic fergusonite besides correlating with the permittivity. Moreover, a larger A-site radius facilitates the acquisition of near-zero TCF values. Notably, the (Sm0.875Bi0.125)NbO4 (SB0.125N) ceramic with εr ≈ 21.9, Q × f ≈ 38 300 GHz (at ∼8.0 GHz), and two different near-zero TCF values of -9.0 (from -40 to +60 °C) and -6.6 ppm/°C (from +60 to +120 °C), respectively, were obtained in the microwave band. A simultaneous increase in the phase transition temperature (Tc) and coefficients of thermal expansion (CTEs) by A-site substitution provides the possibility for promising thermal barrier coating (TBC) materials. Then, a cylindrical dielectric resonator antenna (CDRA) with a resonance at 4.86 GHz and bandwidth of 870 MHz was fabricated by the SB0.125N specimen. The exceptional performance shows that the SB0.125N material is a possible candidate for the sub-6 GHz antenna owing to the advantages of low loss and stable temperature.

Efficient toluene adsorption/desorption on biochar derived from in situ acid-treated sugarcane bagasse.

Carbon-based materials with great adsorption performance are of importance to meet the needs of industrial gas adsorption. Having massive agricultural wastes of sugarcane bagasse, China could use this waste into wealth. However, the comprehensive utilization of sugarcane bagasse as precursor for biochar that can be used as adsorbent has not been extensively explored. In this study, a series of in situ sulfuric acid-modified biochar was prepared by hydrothermal carbonization process. The prepared biochar (SBAC-7) has a combination of two main advantages that are high microporosity (micropore surface area = 1106 m2/g) and being rich in S-containing functional groups on the surface. In particular, SBAC-7 showed an excellent adsorption capacity of toluene (771.1 mg/g) at 30 °C, which is nearly 3 times as high as that of the commercial activated carbons. Meanwhile, it showed great stability and cyclic regeneration performance with five toluene adsorption-desorption test cycles. This study provides a high-performance biochar for the adsorption-desorption cycle in practical engineering applications, and would contribute to the sustainable "sugarcane production-bagasse utilization" circular economy.

High-entropy A2B2O7-type oxide ceramics: A potential immobilising matrix for high-level radioactive waste.

The sustainable development of civil nuclear energy requires the fabrication of the durable nuclear wasteforms, in particular for high-level radioactive waste, which involves the design of the composition and microstructure. Herein, we demonstrated that high-entropy ceramics (Eu1-xGdx)2(Ti0.2Zr0.2Hf0.2Nb0.2Ce0.2)2O7 are the potential candidate as immobilizing hosts for high-level radioactive waste. The static aqueous leaching test indicates that the normalized leaching rates for the simulated radionuclides Ce (LRCe) and Gd (LRGd) in as-prepared high-entropy ceramics are approximately 10-6~10-8 g·m-2·d-1 after 42 days testing, much lower than those reported values in doped-Gd2Zr2O7 (10-6~10-3 g·m-2·d-1). The excellent chemical durability is mainly due to the synergistic effects of the compositional complexity and severe lattice distortion. Compared to their ternary oxides, the low oxygen vacancy concentration slows down the migration and diffusion of cations. Moreover, the lattice distortion increases the lattice potential energy, also inhibiting the migration of cations. This study provides a strategy for the development and application of high-entropy ceramics as the wasteforms.

Engineering lithiophilic Ni-Al@LDH interlayers on a garnet-type electrolyte for solid-state lithium metal batteries.

In this work, a lithiophilic Ni-Al@LDH interlayer is engineered at the Li6.4La3Zr1.4Ta0.6O12 (LLZTO) electrolyte and Li anode interface. The Ni-Al@LDH interlayer can significantly reduce the interfacial resistance as well as give excellent cycling performance both in a symmetric Li//Li cell and solid full lithium metal batteries.

Conjugation with nanodiamonds via hydrazone bond fundamentally alters intracellular distribution and activity of doxorubicin.

Doxorubicin (DOX) has been widely incorporated in various delivery forms for tareted treatment of malignant tumors such as triple-negative breast cancer (TNBC), with numerous studies reporting higher therapeutic efficacy and lower toxicity at the same time. However, little attention has been paid to whether DOX in a delivery form acts with the same actions and processes as in free form at the cellular level. This question was investigated in the present study wherein DOX conjugated with polyglycerol-coated nanodiamonds through the pH-sensitive hydrazone bond (Nano-DOX) was compared with DOX in free form on the 4T1 mouse TNBC model. We first found Nano-DOX to have a distinct intracellular distribution profile from DOX. Internalized Nano-DOX mainly stayed in the lysosomes slowly releasing DOX into the cytoplasm and then the nucleus whereas DOX displayed both nuclear and lysosomal distribution after cell uptake. Next, Nano-DOX was shown to induce endoplasmic reticulum (ER) stress without substantial DNA damage while DOX caused massive DNA damage as well as ER stress. Consequently, Nano-DOX only caused minimal activation of pro-inflammatory signaling mediated by MAPK/ERK, NF-κB and STAT3 as seen in response to DOX-inflicted DNA damage. Consistently, DOX-induced activities of ABC transporters, CXCL-1, GM-CSF and IL-6, which are tumor protective events downstream to the pro-inflammatory signaling, were also minimal in Nano-DOX-treated cancer cells. These findings are compelling proof that a chemotherapy in nano form can have distinct intracellular pharmacokinetics from its free from, which can result in altered cellular effects of the drug. Implications of these findings are discussed with an emphasis on nano-drug design, tumor pharmacology and chemoresistance.

High-Quality-Factor AlON Transparent Ceramics for 5 GHz Wi-Fi Aesthetically Decorative Antennas.

Transparent material has been widely used in product design and has seen a large increase in its use. In this paper, a kind of aesthetically decorative 5 GHz Wi-Fi dielectric resonator antenna (DRA) of aluminum oxynitride (AlON) transparent ceramic has been designed. High-quality-factor AlON transparent dielectric ceramics were fabricated by presintering at 1780 °C and further cold isostatic pressing (CIP) under a 200 MPa argon atmosphere. For a 9.0 mm thick specimen, the in-line light transmittance reached 83%. Optimum dielectric constant (εr = 9.32), quality factor (Qf = 47 960) and temperature coefficient (TCF = -51.7 ppm/°C) was achieved in the AlON transparent ceramic by cold isostatic pressing. As a result, the proposed aesthetically decorative DRA can achieve an impedance bandwidth of 32% (4.48-6.19 GHz), a high radiation efficiency of 85%, and a low cross-polarization discrimination (XPD) of -30 dB. To achieve a broad bandwidth, the proposed antenna was excited in its dominant TE111x mode and higher-order TE113x mode. The proposed antenna is thus an excellent candidate for an indoor decoration Wi-Fi antenna.