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Due to their poor solubility and poor bioavailability, the majority of recently produced novel chemical entities pose significant challenges in the formulation and development of new dosage forms. The pharmaceuticals in Biopharmaceutical Classification System (BCS) classes II and IV have a solubility issue; nanotechnology is the most effective solution to this issue. The preparation of nanocrystals and the numerous methods utilized to create them are the major topics of this review article. Since there is no matrix material present in drug nanocrystals, they are a carrier-free form of drug delivery. For pharmaceuticals in BCS classes II and IV, nanocrystal technologies have been suggested as beneficial, all-purpose formulation methods. The dissolving rate and saturation solubility of active agent can be efficiently increased by nanocrystals because of their higher surface to volume ratio. Major used routes of administration, including oral, IV, SC, IM, and topical administration are acceptable for the nanocrystals drug delivery system. For use in sterile products, nanocrystals can also be added to tablets, capsules, quick melts, and lyophilized materials. Precipitation, milling, high pressure homogenization, and combination methods like Nano-EdgeTM, SmartCrystal® are just a few of the production techniques employed today. [ABSTRACT FROM AUTHOR]

Organic phototransistors, renowned for their exceptional biocompatibility, hold promise in phototherapy for tracking the efficacy of photosensitive drugs within treatment areas. Nevertheless, it has been found that organic semiconductors are less effective in detecting ultraviolet (UV) light because of their narrow bandgap. Here, we show that UV photodetection in phototransistors using donor-acceptor (D-A) polymer semiconductors can be significantly enhanced by incorporating PCBM nanocrystals. This integration results in a band mismatch between the nanocrystals and the D-A polymer at the interface. These nanocrystals also demonstrate a notable capability of modulating threshold voltage under UV light. The devices incorporating nanocrystals exhibit a photoresponsivity of 0.16 A/W, surpassing the photoresponsivity of the devices without nanocrystals by 50%. The specific detection rate of devices with nanocrystals is around 2.00 × 1010 Jones, which is twice as high as that of devices without nanocrystals. The presented findings offer a potential avenue to improve the efficiency of polymer phototransistors for UV detection. [ABSTRACT FROM AUTHOR]

Alloying and solid‐solution formation is a powerful technique that enhances and adds properties through elemental mixing, but unfortunately, some elements simply cannot mix as their chemical nature prevents a thermodynamically stable structure. For example, the inherent nobility of platinum group metals does not favor bond formation and precludes their incorporation into higher (boron‐rich) metal borides. However, we demonstrate that when using five or more constituents, the higher mixing entropy will overcome these chemical limitations and form a stable high‐entropy alloy, demonstrating the formation of new compounds with substituents that are seemingly impossible with a traditional metal alloying approach. The high‐entropy boride (HEB) Al0.2Nb0.2Pt0.2Ta0.2Ti0.2B2 was synthesized, where platinum was forced to occupy a 12‐coordinate site, sandwiched between honeycomb borophene sheets. In addition to the unusual coordination, the boron serves as a poison panacea. Pure platinum is strongly susceptible to sulfur poisoning by adsorption, rendering a platinum catalyst ineffective. Boron is known to be resistant to sulfur poisoning. The boron sheets present in the HEB shield the platinum from sulfur while maintaining high catalytic activity. This is confirmed with the facile hydrogenation of thiol‐containing nitro compounds, where the HEB resists sulfur poisoning while retaining its high catalytic activity. [ABSTRACT FROM AUTHOR]

In this study, we report the results of continuous rotation electron diffraction studies of single DyPO4·nH2O (rhabdophane) nanocrystals. The diffraction patterns can be fit to a trigonal lattice (P3121) with lattice parameters a = 7.019 (5) and c = 6.417 (5) Å. However, there is also a set of diffuse background scattering features present that are associated with a disordered superstructure that is double these lattice parameters and fits with an arrangement of water molecules present in the structure pore. Pair distribution function (PDF) maps based on the diffuse background allowed the extent of the water correlation to be estimated, with 2–3 nm correlation along the c axis and ∼5 nm along the a/b axis. [ABSTRACT FROM AUTHOR]

Luminescent solar concentrators (LSCs) are complementary sunlight collectors for photovoltaics (PVs). Emissive fluorophores embedded in a transparent waveguide collect solar radiation over a large area and convert it into luminescence directed to the PV cells that frame the waveguide's edges. Among various fluorophores, perovskite nanocrystals (PNCs) show considerable potential for LSCs thanks to their wide size/composition/shape tunable broad absorption spectrum ranging from UV to near‐infrared, which significantly overlaps with the solar spectrum. They also feature high brightness with a photoluminescence quantum yield of up to 100% and ease of fabrication through wet chemistry approaches. In addition, PNCs can be engineered to minimize the absorption/emission overlap, which is the key to suppressing energy losses caused by reabsorption. Here, the structure and properties of PNCs and then correlate them with LSC performance is presented. The synthesis of PNCs using wet‐chemistry approaches and summarize the latest developments of PNCs‐based LSCs, categorized by the engineering strategies of PNCs and the design of the LSC configurations is critically reviewed. Finally, it is described major challenges and perspectives for future work, outlining the rational design, synthesis, PNC loading, surface engineering, and machine‐learning‐based tuning of PNC‐LSC. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quaternary Ag 2 SbBiSe 4 NCs are synthesized by a colloidal synthesis route. • Ag 2 SbBiSe 4 has a cubic crystal structure and a wide band gap. • Ag 2 SbBiSe 4 maintains low lattice thermal conductivity of ca. 0.34 W m−1K−1. • Modulation doping through Sn NCs is used to tune the TE performance of Ag 2 SbBiSe 4. • A maximum ZT value of 0.64 at 760 K and a high Vickers Hardness of ~185 Hv are obtained. Materials with low intrinsic thermal conductivity are essential for the development of high-performance thermoelectric devices. At the same time, the solution processing of these materials may enable the cost-effective production of the devices. Herein, we detail a high-yield and scalable colloidal synthesis route to produce Ag 2 SbBiSe 4 nanocrystals (NCs) using amine-thiol-Se chemistry. The quaternary chalcogenide material is consolidated by a rapid hot-press maintaining the cubic crystalline structure. Transport measurements confirm that n -type Ag 2 SbBiSe 4 exhibits an inherently ultralow lattice thermal conductivity of ca. 0.34 W m−1K−1 at 760 K. Moreover, a modulation doping strategy based on the blending of semiconductor Ag 2 SbBiSe 4 and metallic Sn NCs is demonstrated to control the charge carrier concentration in the final composite material. The introduction of Sn nanodomains additionally blocks phonon propagation thus contributing to reducing the thermal conductivity of the final material. Ultimately, a peak thermoelectric figure of merit value of 0.64 at 760 K is achieved for n -type Ag 2 SbBiSe 4 -Sn nanocomposites that also demonstrate a notable Vickers hardness of 185 HV. [ABSTRACT FROM AUTHOR]

Efficient hydrogen production relies on cost-effective and durable non-noble metal electrocatalysts for the hydrogen evolution reaction (HER). In this work, a liquid metal-assisted solid-flame combustion synthesis (SF-CS) method was used to create transition metal carbide TMC) nanocrystals with exposed facets. The TMCs include TiC, VC, NbC, TaC, Ta 2 C, WC, and Mo 2 C. In acidic solutions, the TMC nanocrystals show enhanced conductivity and superior HER performance, as evidenced by their lower Tafel slope, higher current density, and decreased overpotential. In particular, Mo 2 C nanocrystals exhibit an overpotential of 95 mV and a Tafel slope of 26 mV dec−1. These findings highlight a noteworthy improvement over previously reported nanostructures in recent years in terms of the HER properties of Mo 2 C with particular facets. This improvement is attributed to the unique surface characteristics, such as energy and active sites, which are impacted by various factors and require more investigation to meet the intended goals. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly stable perovskite nanocrystals in water were obtained by modifing wool keratin (WK) and crosslinking agent (PAPI). • CPB/WK-PAPI nanocrystals show excellent photoluminescence retention over time even after 512 days (>40 %). • Portable, low cost, and visualize test strips for amines were successfully made from these nanocrystals. Perovskite nanocrystals (PNCs) have emerged as promising candidates for fluorescent probes owing to their outstanding photoelectric properties. However, the conventional CsPbBr 3 (CPB) NCs are extremely unstable in water, which has seriously limited their sensing applications in water environment. Herein, we present a powerful ligand engineering strategy for fabricating highly water-stable CPB NCs by using a biopolymer of wool keratin (WK) as the passivator and the polyaryl polymethylene isocyanate (PAPI) as the cross-linking agent. In particular, WK with multi-functional groups can serve as a polydentate ligand to firmly passivate CPB NCs by the ligand exchange process in hot toluene; and then the addition of PAPI can further encapsulate CPB NCs by the crosslinking reaction between PAPI and WK. Consequently, the as-prepared CPB/WK-PAPI NCs can maintain ∼ 80 % of their relative photoluminescence (PL) intensity after 60 days in water, and they still maintain ∼ 40 % of their relative PL intensity even after 512 days in the same environment, which is one of the best water stabilities compared previously reported polymer passivation methods. As a proof-of their application, the portable CPB/WK-PAPI NCs-based test strips are further developed as a fluorescent nanoprobe for real-time and visual monitoring amines and food freshness. Among various amine analytes, the as-prepared test strips exhibit higher sensitivity towards conjugated amines, achieving a remarkable detection limit of 18.3 nM for pyrrole. Our research not only introduces an innovative strategy involving natural biopolymers to enhance the water stability of PNCs, but also highlights the promising potential of PNCs for visually and portably detecting amines and assessing food freshness. [ABSTRACT FROM AUTHOR]

In this paper, high transmittance glass-ceramics containing Zirconium Yttrium Oxide (Zr 0.82 Y 0.18 O 1.91) nanocrystals were successfully prepared by melt cooling and crystallization heat-treatment method. The effects of Y 2 O 3 concentration on the structure, crystallization performance, transmittance, and indentation fracture toughness of Na 2 O–Al 2 O 3 –B 2 O 3 –SiO 2 –ZrO 2 glass and glass-ceramics were explored. The addition of Y 2 O 3 improved the Vickers hardness (4.81 GPa–5.25 GPa) and indentation fracture toughness (0.78 MPam1/2 to 0.95 MPam1/2) of the glasses. Y 2 O 3 successfully facilitated the precipitation of the non-alkaline crystalline phase Zr 0.82 Y 0.18 O 1.91 at low heat-treatment temperatures. The precipitation of Zr 0.82 Y 0.18 O 1.91 nanocrystals improves the Vickers hardness (5.17 GPa–5.56 GPa) and indentation fracture toughness (0.90 MPam1/2 to 1.01 MPam1/2) in glass-ceramics, while concurrently preserving a high level of visible light transmittance (∼90 %). This demonstrates its potential applications in the field of protective covers for electronic displays. [ABSTRACT FROM AUTHOR]

Despite the various therapeutic benefits and high tolerance of orally administered silybin, poor water-solubility can be the main restrictive physicochemical feature, which results in low oral bioavailability in the absorption. A milk thistle nanocrystal formulation (HM40) was prepared using a modified wet-milling method. Comprehensive characterization was performed to determine the physical morphology, crystallinity, and physicochemical properties. The long-term stability was evaluated over 24 months. In vitro silybin release was assessed at pH 1.2 for 2 h, followed by pH 6.8 for 4 h. Finally, in vivo pharmacokinetic studies were conducted in rats and healthy human volunteers. HM40 exhibited a nanocrystal structure maintaining crystallinity and enhanced the solubility and dissolution of silybin compared to that of the raw material. The stability over 24 months revealed consistent surface morphology, particle size, silybin content, and solubility. In vitro release profiles indicated a significant increase in the silybin release from HM40. In vivo pharmacokinetic studies demonstrated that HM40 showed 2.61- and 1.51-fold higher oral bioavailability in rats and humans, respectively, than that of the reference capsule. HM40 formulation presents a stable and promising approach for the oral delivery of poorly water-soluble silybin, with the potential for use in pharmaceutical formulations containing milk thistle. [ABSTRACT FROM AUTHOR]

In this work, we developed an optimized ultrasonic spray pyrolysis device for obtaining metal oxide films. The key benefit of this facility lies in its cost-effectiveness and its ability to consistently coat extensive surfaces without sacrificing the integrity of the semiconductive films, thus streamlining the manufacturing process of semiconductor films. The resulting films exhibit the following attributes: the thickness of the deposited layer is approximately 400 nm, while the diameters of ZnO1-xSx nanocrystals range from 50 to 200 nm, oriented perpendicular to the crystallographic orientation (111). In the production of nanorods, the average height is estimated to be approximately 30-50 nm, with a density of 2.9×1011 cm-2 being indicated. [ABSTRACT FROM AUTHOR]

In this study, the results of the investigation of the influence of Al atoms on the structural characteristics of ZnO films obtained by the sol- gel method are presented. It has been determined that the glass substrates consist of subcrystallites with dimensions of 28.6 nm, having cubic unit cells with lattice parameters a = 0.3336 nm, and their surfaces belong to the crystallographic orientation (111). It has been identified that the grown thin ZnO films consist of subcrystallites with dimensions of 39.5 nm, having a wurtzite structure with lattice parameters a = b = 0.3265 nm and c = 0.5212 nm, respectively. It has been determined that at the boundaries of the division of these subcrystallites, polycrystalline regions with sizes of 12.6 nm, 28.3 nm, 30 nm, and 33 nm are formed. Additionally, nanocrystallites with sizes of 56.8 nm self-assemble on the surface areas of the deposited films. The increase in the values of the "c"axis of the hexagonal crystal lattice of ZnO films by 0.0009 nm when doping Al atoms from 1% to 5% is explained by the shift of the main structural line (002) at small angles (40-0.12°). It has been established that nanocrystallites with lattice parameters an = 0.5791 nm, belonging to the spatial group Fd3m, self-assemble on the surface areas of ZnO:Al films. the curve due to the presence of a monoenergetic level of fast surface states at the heterojunction. [ABSTRACT FROM AUTHOR]

The growth, yield, and quality of cauliflower (Brassica oleracea var. botrytis L.) cv. Pusa Snowball K-1 were studied using Fe2O3-nano fertilizer (Fe2O3-N) in combination with Azotobacter, Farmyard manure (FYM), and Phosphorus solubilizing bacteria (PSB). Hydrothermally synthesized Fe2O3 nanoparticles characterized with XRD, FTIR, and SEM. The experiment consisting 12 treatments viz. T1 (Fe2O3-N), T2 comprising of Fe2O3-N + FYM + Azotobacter + PSB, T3 (Fe2O3-N + Azotobacter + PSB), T4 (Fe2O3-N + FYM + Azotobacter), T5 (Fe2O3-N + FYM + PSB), T6 (Fe2O3-N + FYM), T7 (Fe2O3-N + Azotobacter), T8 (Fe2O3-N + PSB), T9 (PSB), T10 (Azotobacter), T11 (FYM), and T12 (control). Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield. Application of Fe2O3-nano fertilizer (Fe2O3-N) along the Azotobacter, FYM, and PSB was shown encouraging growth effects to improve the cropping behavior. Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield. This research is a detailed study of nontoxic Fe2O3 nanoparticle as nanofertilizers on the cauliflower (Brassica oleracea var. Botrytis L.) cv. Pusa Snowball K-1. Growth of nanoparticles was carried out by environment friendly hydrothermal method. It was found that Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield. The novelty of this work is that nanoparticles are used to enhance the growth and yield of the crop. This research will reflect new point of view toward the nanoparticle as nanofertilizers instead of indiscriminate use of chemical fertilizers and pesticides to increase the yield of crop. [ABSTRACT FROM AUTHOR]

Plant fibers have been studied as sources of nanocellulose due to their sustainable features. This study investigated the effects of acid hydrolysis parameters, reaction temperature, and acid concentration on nanocellulose yield from maguey (Agave cantala) fiber. Nanocellulose was produced from the fibers via the removal of non-cellulosic components through alkali treatment and bleaching, followed by strong acid hydrolysis for 45 min using sulfuric acid (H2SO4). The temperature during acid hydrolysis was 30, 40, 50, and 60 °C, and the H2SO4 concentration was 40, 50, and 60 wt. % H2SO4. Results showed that 53.56% of raw maguey fibers were isolated as cellulose, that is, 89.45% was α-cellulose. The highest nanocellulose yield of 81.58 ± 0.36% was achieved from acid hydrolysis at 50 °C using 50 wt. % H2SO4, producing nanocellulose measuring 8–75 nm in diameter and 72–866 nm in length, as confirmed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Fourier-transform infrared spectroscopy (FTIR) analysis indicated the chemical transformation of fibers throughout the nanocellulose production process. The zeta potential analysis showed that the nanocellulose had excellent colloidal stability with a highly negative surface charge of −37.3 mV. Meanwhile, X-ray diffraction (XRD) analysis validated the crystallinity of nanocellulose with a crystallinity index of 74.80%. Lastly, thermogravimetric analysis (TGA) demonstrated that the inflection point attributed to the cellulose degradation of the produced nanocellulose is 311.41 °C. [ABSTRACT FROM AUTHOR]

After 3 h of irradiation, the H 2 O 2 accumulation of BiPO 4 nanocrystals (BIP NCs) reaches 30.44 mM·g−1, which is 3.13 times higher compared to bulk BiPO 4 (BIP-B) synthesized through hydrothermal synthesis. This significant increase can be attributed to the nanocrystal structure, which shortens charge migration distance. Consequently, the path of H 2 O 2 production is altered from a two-step one-electron pathway to a more efficient one-step two-electron pathway. [Display omitted] The photocatalytic production of H 2 O 2 has gained recognition as an economical and eco-friendly technology, but it suffers from limitations such as low production rates and difficulty in achieving high concentrations. This study was designed to overcome these limitations by preparing BiPO 4 nanocrystals (BIP NCs) via high-temperature hydrolysis, and X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicated that BIP NCs with particle sizes of 8.5 ± 3 nm were synthesized. In a photocatalytic performance test, only H 2 O and O 2 were used to produce H 2 O 2 , resulting in an accumulation of H 2 O 2 of up to 30.44 mM·g−1, as measured with the potassium titanium oxalate method; this value was 3.13 times greater than that of bulk BiPO 4 (BIP-B). The resulting nanocrystals demonstrated superior electron-hole transport and separation efficiency compared to those of BIP-B, and H 2 O 2 was formed in a one-step two-electron process. Furthermore, a film composed of a gas diffusion layer (GDL) and BIP NCs provided continuous accumulation of H 2 O 2 ; a concentration of 7.23 mM was achieved after 96 h of reaction, and the stability of the film was confirmed by comparing scanning electron microscopy (SEM) images obtained before and after the reaction. Construction of a nanocrystalline structure to enhance the activities of photocatalysts and films and achieve continuous accumulation of H 2 O 2 will provide insights into the photocatalytic production of highly concentrated H 2 O 2. [ABSTRACT FROM AUTHOR]

The crystal growth of hydroxyapatite (HAp) using a solvothermal method was investigated under various reaction conditions. The purpose of the present study is the synthesis of HAp nanocrystals with multiple facets and the atomic arrangement for various orientations of the crystal was clarified. HAp nanorods were obtained at 200°C after 24 h using a reaction medium of water. The atomic arrangement in HAp nanorods was examined for a characteristic facet in the direction of [21−13−] and [0110−] incidences and crystal orientation along the c‐axis of HAp nanorod was confirmed using electron microscopy. The present study clarifies the HAp crystal growth mechanism, where the adsorption of cations or anions onto the crystal facet determines the HAp crystal shape. The crystals of HAp grew along the c‐axis and became rod‐shaped suggesting that cations were adsorbed predominantly over anions. [ABSTRACT FROM AUTHOR]

The conditions and parameters for the synthesis of metal oxide films (ZnO, SnO2, and Zn2SnO4) by spray pyrolysis have been determined. The films were synthesized from aqueous solutions; the main differences between the methods were in the composition of the precursors, in the modes and time of deposition. The crystal structure of the Zn2SnO4 film corresponds to the cubic lattice, which belongs to the space group Fd3m with blocks 53 nm in size and lattice parameters a = 6.238 Å. Films of SnO2 and ZnO nanocrystallites 28 and 31 nm in size coherently arranged with lattices in the volume of thin Zn2SnO4 films can exhibit quantum size effects, which is of interest for modern nanotechnology. The crystals of the obtained SnO2 films have a tetragonal Bravais lattice with the space group P4 2/mnm with lattice parameters a = b = 4.836 Å and c = 3.245 Å, and the size of the SnO2 film subcrystals is 61 nm. The resulting ZnO films belong to the C6/mmc space group and the crystal lattice has a hexagonal syngony with the wurtzite structure with parameters a = b = 0.3265 nm and c = 0.5212 nm. It has been determined that, on the surface of the thin film grown, zinc oxide bumps with sizes LZnO ≈ 84 nm appear, which affect the unique properties of the samples. It is shown that the resulting thin Zn2SnO4, SnO2, and ZnO films can be used in a wide range of applications from sensitive sensor elements to coatings in transparent electronics in terms of their optical parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] It was established that the particle size of titanium oxide β-Ti 3 O 5 has a great influence on the processes of phase formation and the stability of particles during heating. It was shown that at a temperature of about 456 K, β-Ti 3 O 5 micro crystals undergo a reversible first-order phase transition, in which the low- temperature β-Ti 3 O 5 phase is transformed into the high-temperature λ- Ti 3 O 5 phase, and at higher temperatures the β-Ti 3 O 5 phase is partially oxidized to form the Magnéli phase Ti 4 O 7. It was found that β-Ti 3 O 5 nanocrystals are unstable in an argon atmosphere and at temperatures above 400 K the β-Ti 3 O 5 powder is oxidized. [ABSTRACT FROM AUTHOR]

Exploration of medicines for efficient and safe management of metabolic‐associated fatty liver disease (MAFLD) remains a challenge. Obeticholic acid (OCA), a selective farnesoid X receptor agonist, has been reported to ameliorate injury and inflammation in various liver diseases. However, its clinical application is mainly limited by poor solubility, low bioavailability, and potential side effects. Herein a hepatic‐targeted nanodrugs composed of OCA and cholesterol‐lowering atorvastatin (AHT) with an ideal active pharmaceutical ingredient (API) content for orally combined treatment of MAFLD is created. Such carrier‐free nanocrystals (OCAHTs) are self‐assembled, not only improving the stability in gastroenteric environments but also achieving hepatic accumulation through the bile acid transporter‐mediated enterohepatic recycling process. Orally administrated OCAHT outperforms the simple combination of OCA and AHT in ameliorating of liver damage and inflammation in both acetaminophen‐challenged mice and high‐fat diet‐induced MAFLD mice with less systematic toxicity. Importantly, OCAHT exerts profoundly reverse effects on MAFLD‐associated molecular pathways, including impairing lipid metabolism, reducing inflammation, and enhancing the antioxidation response. This work not only provides a facile bile acid transporter‐based strategy for hepatic‐targeting drug delivery but also presents an efficient and safe full‐API nanocrystal with which to facilitate the practical translation of nanomedicines against MAFLD. [ABSTRACT FROM AUTHOR]

Wet media milling is a fully industrialized technology for the manufacturing of drug nanocrystal suspensions. This work describes the development of an advanced control strategy and an associated design space for a manufacturing process at a commercial scale. Full-scale experiments and mechanistic process modeling have been used to establish a physically reasonable control strategy of factors relevant to the quality attributes of the nanocrystal suspension. The design space has been developed based on a mature mechanistic process model of the wet media milling procedure. It presents the process–product attribute relationship between a multidimensional range of measured process parameters and a range of the product-quality attribute mean particle sizes. The control strategy allows for simple, robust, and sound scientific process control as well as the operational flexibility of the suspension batch size. This is an industrial case study of control strategy and design-space definition with the crucial contribution of mechanistic process modeling for an intended commercial manufacturing process. [ABSTRACT FROM AUTHOR]

Improving the mechanical strength of electrospun ceramic ultrafine fibers (UFs) is crucial for both structural and functional applications. Herein, we report a facile strategy of in-situ embedding ZrO 2 nanocrystals (NCs) in polycarbosilane-derived silicon carbide (SiC) UFs. The morphology, chemical composition, mechanical properties, and cross-section morphologies of single UFs are characterized to investigate the effects of introducing ZrO 2 NCs. Notably, a single ZrO 2 NCs/SiC UF with an average ZrO 2 NCs size of 4.5 ± 1.3 nm possesses optimum mechanical performance, it exhibits about 371.3% increase in tensile strength and 6 times improvement in fracture energy when compared with SiC UFs. The uniformly distributed ZrO 2 NCs increase the fiber density that reduce the internal defects, which improve the strength of SiC UF. The enhanced fracture energy can be attributed to the efficient fracture energy dissipation mechanism related to the NCs size. This work provides a viable strategy for designing ceramic fibers with enhanced mechanical properties. [ABSTRACT FROM AUTHOR]

To lower the sintering temperature and improve the mechanical properties of aluminum titanate (AT, Al2TiO5) flexible ceramics, γ‐Al2O3 is employed to partially replace the α‐Al2O3 as the starting powder. The results show that the addition of γ‐Al2O3 is sufficient to promote the reaction, improve the flexibility, raise the strength, and accelerate the grain growth of AT flexible ceramics when sintered at 1300°C. With that, the combination of optimum fracture strength (∼33.52 MPa) and high flexibility (∼1.05%) is obtained when the addition of γ‐Al2O3 is 20 wt.%. As compared to the virgin, the optimization of 21.67% in fracture strength and 176% in strain can be obtained. It is believed that the increase of crack deflection and branching should take the responsibility. However, the mechanical strength degrades with the increase of sintering temperature, which is caused by the grain defects that reduce the bearing capacity of AT grains and lead to the grain fracture model transition. In addition, the effect of γ‐Al2O3 content on AT grain growth transfers from promotion to inhibition with the increase of sintering temperature. The main reason is that the growth of the nanocrystals at AT grain boundary causes the uneven distribution of the intermediate phase, leading to the roughening transition of the boundary and hence reducing the grain growth rate. On these bases, the grain growth mechanism that dominates by grain boundary is proposed. It is believed that the discovery of this study will provide a new grain growth model and the reference for solving the abnormal grain growth or grain growth stagnation. [ABSTRACT FROM AUTHOR]

Crystallographic analysis relies on the scattering of quanta from arrays of atoms that populate a repeating lattice. While large crystals built of lattices that appear ideal are sought after by crystallographers, imperfections are the norm for molecular crystals. Additionally, advanced X-ray and electron diffraction techniques, used for crystallography, have opened the possibility of interrogating micro- and nanoscale crystals, with edges only millions or even thousands of molecules long. These crystals exist in a size regime that approximates the lower bounds for traditional models of crystal nonuniformity and imperfection. Accordingly, data generated by diffraction from both X-rays and electrons show increased complexity and are more challenging to conventionally model. New approaches in serial crystallography and spatially resolved electron diffraction mapping are changing this paradigm by better accounting for variability within and between crystals. The intersection of these methods presents an opportunity for a more comprehensive understanding of the structure and properties of nanocrystalline materials. [ABSTRACT FROM AUTHOR]

Uniform PdAuAg alloy nanocrystals with tunable compositions are facilely prepared via a one-pot synthesis. The use of carbon monoxide as the effective agent is crucial to assist the reduction of multiple metallic precursors simultaneously, which is greenly released from in situ thermal decomposition of W(CO)6 in a capped glass vial. The resulting PdAuAg products are featured within the size range of 9.3~11.7 nm and quasi-spherical shape, and their elemental compositions can be readily tuned by varying the molar ratios of corresponding metallic precursors. Interestingly, when the reductant is varied from carbon monoxide to ascorbic acid, the resulting products showed Au@PdAg core-shell elemental distribution, indicating the necessary role of carbon monoxide in dominating the formation of PdAuAg nanocrystals with a fully alloy phase. Using the reduction of 4-nitrophenol as the model reaction, their catalytic properties are evaluated, where the Pd4.1Au3.3Ag2.6 nanocrystals showed the highest apparent rate constant. Results from DFT simulations prove that the 4-nitrophenol adsorption shows a facet and atomic ratio-dependent behavior. The current work provides a feasible strategy to create trimetallic nanocrystals with isotropic shapes and tunable compositions, which could be potentially extended to other metals/alloys. [ABSTRACT FROM AUTHOR]

Canagliflozin (CFZ) is a sodium-glucose cotransporter-2 inhibitor (SGLT2) that lowers albuminuria in type-2 diabetic patients, cardiovascular, kidney, and liver disease. CFZ is classified as class IV in the Biopharmaceutical Classification System (BCS) and is characterized by low permeability, solubility, and bioavailability, most likely attributed to hepatic first-pass metabolism. Nanocrystal-based sublingual formulations were developed in the presence of sodium caprate, as a wetting agent, and as a permeability enhancer. This formulation is suitable for children and adults and could enhance solubility, permeability, and avoid enterohepatic circulation due to absorption through the sublingual mucosa. In the present study, formulations containing various surfactants (P237, P338, PVA, and PVP K30) were prepared by the Sono-homo-assisted precipitation ion technique. The optimized formula prepared with PVP-K30 showed the smallest particle size (157 ± 0.32 nm), Zeta-potential (−18 ± 0.01), and morphology by TEM analysis. The optimized formula was subsequently formulated into a sublingual tablet containing Pharma burst-V® with a shorter disintegration time (51s) for the in-vivo study. The selected sublingual tablet improved histological and biochemical markers (blood glucose, liver, and kidney function), AMP-activated protein kinase (AMPK), and protein kinase B (AKT) pathway compared to the market formula, increased CFZ's antidiabetic potency in diabetic rabbits, boosted bioavailability by five-fold, and produced faster onset of action. These findings suggest successful treatment of diabetes with CFZ nanocrystal-sublingual tablets. [ABSTRACT FROM AUTHOR]

The photoluminescence of lithium fluoride nanocrystals and crystals placed on the anode of an atmospheric-pressure glow discharge in helium and exposed to the discharge components was studied. The luminescence spectra showed that color centers with new properties inherent to near-cluster centers were formed in unannealed nanocrystals after exposure to the discharge. However, the conditions necessary for formation of near-cluster centers were eliminated upon annealing of the nanocrystals. These necessary conditions were partially restored when annealed nanocrystals were exposed to the discharge. This opened new possibilities for elucidating the processes and mechanisms of formation of centers with new properties. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) undergoes degradation through the action of microorganisms and enzymes that can degrade it by composting. The goal of this work was to observe the degradation/disintegration behavior in garden soil of neat PLA and PLA composites with 3 wt% cellulose nanocrystals (CNC) modified or not with non-ionic surfactants (S) at a weight ratio of 1:1 (CNC:S). Four types of non-ionic surfactants with hydrophilic-lipophilic balance (HLB) ranging from 4.3 to 16.7 were tested: sorbitan monolaurate (Span 20), sorbitan monooleate (Span 80), polyoxyethylene sorbitan monolaurate (Tween 20) and polyoxyethylene sorbitan monooleate (Tween 80). Films were obtained by solution casting, cut into 2 × 2 cm strips and buried in garden soil, while monitoring the temperature and humidity for 150 days. Changes in the films by visual inspection, polarized light microscopy, thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR) were observed. Results showed that the addition of surfactants favored the rate of biodegradation of the composites, being the lowest molecular weight the determinant property of the surfactant to enhance biodegradation rate of PLA/CNC/S composites. Nevertheless, for surfactants belonging to the same chemical family, the highest biodegradation rate for PLA/CNC/S composite obeys the principle of high HLB, and low spherulite size. [ABSTRACT FROM AUTHOR]

The purpose of the current research aimed to evaluate the in vivo pharmacokinetics parameters of the formulated cilnidipine nanocrystals (CLND NCs) after oral dosing in comparison to orally CLND dispersion. Cilnidipine is a Ca+2 channel blocker applied to control elevated blood pressure and its vascular prognosis. The solvent-anti-solvent method was utilized to prepare CLND NCs. The bioavailability parameters were measured in male Westar rats (n = 12), and each rat weighed between 200 ±20 grams. Rats were split up into two groups with an equal number in each (n=6). All groups fasted for twelve hours permitting water to be consumed before the trial. Blood samples (a half mL) were withdrawn from the retro-orbital venous plexus at (5, 15, 30, 45 minutes) and (1.0 2.0, 6.0, 8.0, 10.0, 12.0 hours) after receiving. Furthermore, the CLND plasma concentration of rats was calculated using HPLC. Findings showed that the relative bioavailability of CLD NCs was approximately 2.17 folds higher in comparison with the bulk CLND, and the maximum plasma concentration at (CPmax) was also increased. As well, the Tmax of the CLND NCs was less than pure drugs. The Conclusion achieved that overall results suggest that the developed CLND NCs was a proper mean for the promotion rate of dissolution and oral bioavailability of CLND. [ABSTRACT FROM AUTHOR]

Glaucoma is a leading cause of irreversible blindness and is characterized by increased intraocular pressure (IOP) and progressive optic nerve damage. The current therapeutic approaches for glaucoma management, such as eye drops and oral medications, face challenges including poor bioavailability, low patient compliance, and limited efficacy. In recent years, nanotechnology has emerged as a promising approach to overcome these limitations and revolutionize glaucoma treatment. In this narrative review, we present an overview of the novel nanotechnologies employed in the treatment of primary open-angle glaucoma. Various nanosystems, including liposomes, niosomes, nanoparticles, and other nanostructured carriers, have been developed to enhance the delivery and bioavailability of antiglaucoma drugs. They offer advantages such as a high drug loading capacity, sustained release, improved corneal permeability, and targeted drug delivery to the ocular tissues. The application of nanotechnologies in glaucoma treatment represents a transformative approach that addresses the limitations of conventional therapies. However, further research is needed to optimize the formulations, evaluate long-term safety, and implement these nanotechnologies into clinical practice. With continued advancements in nanotechnology, the future holds great potential for improving the management and outcomes of glaucoma, ultimately preserving vision and improving the lives of millions affected by this debilitating disease. [ABSTRACT FROM AUTHOR]

Herein, we employed the sol–gel technique to synthesize Cu2O-based nanocrystals with Co and Na doping and co-doping, respectively. A correlation was established among several characterizations of cuprous oxide-based nanocrystals to observe their feasibility in the field of energy materials. Raman spectra typically show the formation of Cu2O, whereas, in the case of Na co-doping, it exhibits the partial presence of CuO. This form of the results prompts the conductivity of nanocrystal samples to be enhanced. According to the current–voltage measurement, the current response slightly increases as doping and co-doping concentrations rise, in which Na5% co-doped Cu2O:Co shows the optimum. Photoluminescence (PL) lifetime measurement shows increases in relative PL lifetime intensity caused by Na doping, which may be attributed to oxygen vacancies. Moreover, it is observed from the cyclic voltammetry (CV) profile that the Na and Co-doped concentration significantly enhances energy storage capability. The electrode using Na5%Cu2O:Co has shown capacitive retention of 69% after 500 GCD cycles @ 10 A g–1. This indicates the practical applicability of these developed cuprous oxide-based nanocrystals as electrode materials for improved electrochemical property. Eventually, the charge–discharge was performed at different current densities, in which specific capacitance was consistent with the CV result. [ABSTRACT FROM AUTHOR]

This article describes a systematic study of the oxidative etching and regrowth behaviors of Pd nanocrystals, including single‐crystal cubes bounded by {100} facets, single‐crystal octahedra and tetrahedra enclosed by {111} facets; and multiple‐twinned icosahedra covered by {111} facets and twin boundaries. During etching, Pd atoms are preferentially oxidized and removed from the corners regardless of the type of nanocrystal, and the resultant Pd2+ ions are then reduced back to elemental Pd. For cubes and icosahedra, the newly formed Pd atoms are deposited on the {100} facets and twin boundaries, respectively, due to their relatively higher energies. For octahedra and tetrahedra, the Pd atoms self‐nucleate in the solution phase, followed by their growth into small particles. We can control the regrowth rate relative to etching rate by varying the concentration of HCl in the reaction solution. As the concentration of HCl is increased, 18‐nm Pd cubes are transformed into octahedra of 23, 18, and 13 nm, respectively, in edge length. Due to the absence of regrowth, however, Pd octahedra are transformed into truncated octahedra, cuboctahedra, and spheres with decreasing sizes whereas Pd tetrahedra evolve into truncated tetrahedra and spheres. In contrast, Pd icosahedra with twin boundaries on the surface are converted to asymmetric icosahedra, flower‐like icosahedra, and spheres. This work not only advances the understanding of etching and growth behaviors of metal nanocrystals with various shapes and twin structures but also offers an alternative method for controlling their shape and size. [ABSTRACT FROM AUTHOR]

CsPbBr3 perovskite nanocrystals (NCs)/ethylene vinyl acetate (EVA) composite flexible films were synthesized through a two‐step process. Firstly, CsPbBr3 nanocrystals with size of ~15 nm were synthesized via hot‐injection method, then the nanocrystals were dispersed in toluene as well as dissolution of EVA. The as‐prepared films emitting high purity of 90 % green color and photoluminescence quantum yield (PLQY) of 80 % with CsPbBr3 nanocrystals loading of 5 % wt under X‐ray. Owing to the EVA encapsulating of CsPbBr3, the composites show long‐term stable luminescent properties in atmosphere and even in water. Also, with the EVA as matrix, the composite films are ponent to be repeated bent for 1500 cycles without losing PL intensity property obviously. The X‐ray image with high contrast was captured at dose rate of ~25 μGyair/s(~0.09 Gy/h), that were estimated via calibrated apparatus. These results indicate that the CsPbBr3/EVA composite film has great potential application in fields of radiation detection and especially of X‐ray imaging. [ABSTRACT FROM AUTHOR]

Polyaniline‐capped mesoporous carbon nanosheets with high conductivity and porosity are synthesized by vapor deposition polymerization. The mesoporous carbon template is prepared by removing ordered cubic iron oxide nanocrystals embedded in the carbon matrix obtained by thermal decomposition of an iron‐oleate complex in a sodium chloride matrix. The evaporated aniline monomers are slowly polymerized on the carbon surface pretreated with FeCl3 as an initiator, partially filling the carbon pores to improve conductivity. The resulting products exhibit efficient hybrid energy storage mechanisms of electric double‐layer capacitance and pseudocapacitance. When the nanosheets are assembled for a symmetric supercapacitor, the device capacitance reaches 107.8 F g−1, at a current density of 0.5 A g−1, and a capacitance retention of 69.6% is achieved at a ten times higher current density of 5 A g−1. Electrochemical impedance spectroscopy reveals that the transition from resistive to capacitive behavior occurs within 0.63 s, indicating that fast ion and charge transport results in high capacitance and rate capability. The corresponding energy and power densities are 9.59 Wh kg−1 and 200.1 W kg−1 at a current density of 0.5 A g−1, demonstrating efficient energy storage in a symmetric supercapacitor. [ABSTRACT FROM AUTHOR]

Halide perovskite nanocrystals (PNCs) are a new kind of luminescent material for fluorescent probes. Compared with traditional nanosized luminescent materials, PNCs have better optical properties, such as high fluorescence quantum yield, tunable band gap, low size dependence, narrow emission bandwidth, and so on. Therefore, they have broad application prospects as fluorescent probes in the detection of agriculture- and food-related hazardous substances. In this paper, the structure and basic properties of PNCs are briefly described. The water stabilization methods, such as polymer surface coating, ion doping, surface passivation, etc.; are summarized. The recent advances of PNCs such as fluorescent probes for detecting hazardous substances in the field of agricultural and food are reviewed, and the detection effect and mechanism are discussed and analyzed. Finally, the problems and solutions faced by PNCs as fluorescent probes in agriculture and food were summarized and prospected. It is expected to provide a reference for further application of PNCs as fluorescent probes in agriculture and food. [ABSTRACT FROM AUTHOR]

Advancing inverted (p‐i‐n) perovskite solar cells (PSCs) is critical for commercial applications given their compatibility with different bottom cells for tandem photovoltaics, low‐temperature processability (≤100 °C), and promising operational stability. Although inverted PSCs have achieved an efficiency of over 25 % using doped or expensive organic hole transport materials (HTMs), their synthesis cost and stability still cannot meet the requirements for their commercialization. Recently, dopant‐free and low‐cost non‐stoichiometric nickel oxide nanocrystals (NiOx NCs) have been extensively studied as a low‐cost and effective HTM in perovskite optoelectronics. In this minireview, we summarize the synthesis and surface‐functionalization methods of NiOx NCs. Then, the applications of NiOx NCs in other perovskite optoelectronics beyond photovoltaics are discussed. Finally, we provide a perspective for the future development of NiOx NCs for the commercialization of perovskite optoelectronics. [ABSTRACT FROM AUTHOR]

Advancing inverted (p‐i‐n) perovskite solar cells (PSCs) is critical for commercial applications given their compatibility with different bottom cells for tandem photovoltaics, low‐temperature processability (≤100 °C), and promising operational stability. Although inverted PSCs have achieved an efficiency of over 25 % using doped or expensive organic hole transport materials (HTMs), their synthesis cost and stability still cannot meet the requirements for their commercialization. Recently, dopant‐free and low‐cost non‐stoichiometric nickel oxide nanocrystals (NiOx NCs) have been extensively studied as a low‐cost and effective HTM in perovskite optoelectronics. In this minireview, we summarize the synthesis and surface‐functionalization methods of NiOx NCs. Then, the applications of NiOx NCs in other perovskite optoelectronics beyond photovoltaics are discussed. Finally, we provide a perspective for the future development of NiOx NCs for the commercialization of perovskite optoelectronics. [ABSTRACT FROM AUTHOR]

It has been shown experimentally that light sources can be produced from commercial blue LEDs and two narrow-band nanocrystalline phosphors (CsPbBr3 and CdSe/CdZnS) that simultaneously satisfy the following criteria: the emission spectrum maximum corresponds to the peak of human vision sensitivity at night (505 nm); the color coordinates in the CIE 1931 standard are close to the point [0.33; 0.33]; the correlated color temperature CCT ~ 6000 K with the possibility of moving to warmer light with CCT ~ 4500 K; and the full range of possible colors (gamut) exceeds the norms of the HDTV standard, approaching the UHDTV standard. It is noted that for serious progress in the development of lighting sources adapted to human night and twilight vision, metrological standards and corrected units of brightness and luminous intensity must be developed while refusing to use the color rendering index for night and twilight lighting. [ABSTRACT FROM AUTHOR]

Thermoluminescence spectra in the temperature range 80–300 K were compared for lithium fluoride nanocrystals and crystals. Four and one band were observed in the spectra of nanocrystals and crystals, respectively. Thermoluminescence intensities integrated over the spectrum and temperature range were measured for two types of lithium fluoride samples in one of which radiation color centers with new properties could form and in the other of which they could not form. The intensity was found to be significantly higher in samples of the first type. [ABSTRACT FROM AUTHOR]

Nanomedicine is a branch of medicine using nanotechnology to prevent and treat diseases. Nanotechnology represents one of the most effective approaches in elevating a drug's treatment efficacy and reducing toxicity by improving drug solubility, altering biodistribution, and controlling the release. The development of nanotechnology and materials has brought a profound revolution to medicine, significantly affecting the treatment of various major diseases such as cancer, injection, and cardiovascular diseases. Nanomedicine has experienced explosive growth in the past few years. Although the clinical transition of nanomedicine is not very satisfactory, traditional drugs still occupy a dominant position in formulation development, but increasingly active drugs have adopted nanoscale forms to limit side effects and improve efficacy. The review summarized the approved nanomedicine, its indications, and the properties of commonly used nanocarriers and nanotechnology. [ABSTRACT FROM AUTHOR]

The growth of nanocrystals (NCs) from metal oxide-based substrates with exposed high-energy facets is of particular importance for many important applications, such as solar cells as photoanodes due to the high reactivity of these facets. The hydrothermal method remains a current trend for the synthesis of metal oxide nanostructures in general and titanium dioxide (TiO2) in particular since the calcination of the resulting powder after the completion of the hydrothermal method no longer requires a high temperature. This work aims to use a rapid hydrothermal method to synthesize numerous TiO2-NCs, namely, TiO2 nanosheets (TiO2-NSs), TiO2 nanorods (TiO2-NRs), and nanoparticles (TiO2-NPs). In these ideas, a simple non-aqueous one-pot solvothermal method was employed to prepare TiO2-NSs using tetrabutyl titanate Ti(OBu)4 as a precursor and hydrofluoric acid (HF) as a morphology control agent. Ti(OBu)4 alone was subjected to alcoholysis in ethanol, yielding only pure nanoparticles (TiO2-NPs). Subsequently, in this work, the hazardous chemical HF was replaced by sodium fluoride (NaF) as a means of controlling morphology to produce TiO2-NRs. The latter method was required for the growth of high purity brookite TiO2 NRs structure, the most difficult TiO2 polymorph to synthesize. The fabricated components are then morphologically evaluated using equipment, such as transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), electron diffraction (SAED), and X-ray diffraction (XRD). In the results, the TEM image of the developed NCs shows the presence of TiO2-NSs with an average side length of about 20–30 nm and a thickness of 5–7 nm. In addition, the image TEM shows TiO2-NRs with diameters between 10 and 20 nm and lengths between 80 and 100 nm, together with crystals of smaller size. The phase of the crystals is good, confirmed by XRD. The anatase structure, typical of TiO2-NS and TiO2-NPs, and the high-purity brookite-TiO2-NRs structure, were evident in the produced nanocrystals, according to XRD. SAED patterns confirm that the synthesis of high quality single crystalline TiO2-NSs and TiO2-NRs with the exposed {001} facets are the exposed facets, which have the upper and lower dominant facets, high reactivity, high surface energy, and high surface area. TiO2-NSs and TiO2-NRs could be grown, corresponding to about 80% and 85% of the {001} outer surface area in the nanocrystal, respectively. [ABSTRACT FROM AUTHOR]

We herein report a facile two‐pot method to prepare a series of the two‐dimensional Ni(OH)2 nanocrystals with varied surface structures via the in‐situ surface transformation derived from Nickel metal‐organic framework (Ni‐MOF) in KOH solution at room temperature. The Ni(OH)2 obtained at the KOH concentration of 0.25 M displayed superior performance among the samples in terms of activities and stability. Further investigation proves that the enhanced urea oxidation reaction (UOR) activities can be ascribed to the cooperation of the larger electrochemical surface area, a faster electronic transfer speed, and a lower transfer resistance on the surface. These findings provide a new route for the rational design and synthesis of advanced electrocatalysts with relatively lower energy consumption that aims to be large‐scale synthesized and utilized in clean energy conversion and applications. [ABSTRACT FROM AUTHOR]

It is shown that the classical theory of phase transitions is inapplicable for the accurate description of melting processes in nanocrystals. In the paper, the theory of non-classical vacancies is used for this description. In particular, the energy of a nanocrystal containing such defects is evaluated. It is found that the nanocrystal lattice loses its mechanical stability at a certain temperature, T F. This loss of stability is associated with the melting process, and the temperature, T F , is considered as the nanocrystal melting point. At some conditions (for some range of nanocrystal sizes), this temperature may increase with the decrease of the nanocrystal size that agrees with the results of recent experimental studies. [ABSTRACT FROM AUTHOR]

Drugs are a crucial commercial good in our lifestyle because they help us stay healthy and treat illnesses. Poor solubility, permeability, bioavailability, dissolving rate, hygroscopicity, tablet ability, compressibility, and stability of medicines are major causes of medication failure during clinical development. To overcome the shortcomings of pharmaceuticals, several methods can be created including salt formation, Nano-formulations, co-solvency, complexation with cyclodextrins and surfactants, micronization, solid dispersions, coamorphous formulations, cocrystallization, nanococrystallization, etc. Nanococrystallization is the approach that has the best chance of enhancing the physical and chemical characteristics of APIs without altering their chemical composition. With the extra advantage of a carrier-free delivery route, nanococrystallization offers a flexible technique for saving poorly soluble medicines. In this review, we provide a comprehensive analysis of nanococrystals. In these we also compare the cocrystal with nano cocrystal along with the formulation methods, advantages and characterization techniques for nanococrystals. [ABSTRACT FROM AUTHOR]

Flubendazole (FLU) is a long-established antihelmintic drug that has been shown to exhibit promising activity against several cancer types, including lung cancer, which stands out for being aggressive and resistant to current therapies. In this work, we developed a new FLU nanocrystal through microfluidization followed by freeze-dried (FD) methods. By combining this method with statistical design, results revealed a significant influence of TPGS concentration on particle size reduction, favoring the achievement of the lowest mean particle size with superior performance and better physicochemical stability than polysorbate 80 and poloxamer 188. Also, thorough characterization analysis revealed the preparation methods did not interfere with the preservation of the drug structure, providing improved perspective on the therapeutic effect. Our preliminary in vivo study showed that FD–FLU-nanocrystal exhibits expressive ability to retard tumor progression and decreases the size of tumors of approximately 40% in A549R xenograft mouse model, when compared to the control group. This is the first development and optimization of a FLU nanocrystal, where results of preliminary in vivo study reinforce the great potential of this nanotechnology-based formulation to overcome FLU limitations, to be a new alternative for the cancer treatment. [ABSTRACT FROM AUTHOR]

Amorphous solid dispersions (ASDs) based on proteins as co-formers have previously shown promising potential to improve the solubility and bioavailability of poorly water-soluble drugs. In particular, whey proteins have shown to be promising co-formers and amorphous stabilizers in ASD formulations, including at high drug loading. In this study, the feasibility of the whey protein β-lactoglobulin (BLG) as a co-former in ASDs was compared to the more traditional ASD co-formers based on synthetic polymers (hydroxypropyl methylcellulose acetate succinate and Eudragit® L) as well as to a nanocrystalline formulation. The poorly water-soluble drug rifaximin (RFX) was chosen as the model drug. All drug/co-former formulations were prepared as fully amorphous ASDs by spray drying at 50% (w/w) drug loading. The BLG-based ASD had the highest glass transition temperature and showed a faster dissolution rate and higher drug solubility in three release media with different pH values (1.2, 4.5, and 6.5) compared to the polymer-based ASDs and the nanocrystalline RFX. In conclusion, BLG is a promising co-former and amorphous stabilizer of RFX in ASD formulations, superior to the selected polymer-based ASD systems or the nanocrystalline formulation. [ABSTRACT FROM AUTHOR]

The refractive index change of semiconductor nanocrystals must be known when designing precision optical components based on semiconductor nanocrystals. In this study, Kramers-Kronig transformation has been used to compute the linear refractive index change of cadmium selenide (CdSe) nanocrystals embedded in glass. Classical theory and numerical computation of Kramers-Kronig relation have been given and explained in detail. CdSe nanocrystals have been grown in borosilicate glass by using melting, rapid-cooling, and heat treatment procedure. Compared to the production studies of semiconductor nanocrystals in borosilicate glass in the literature, the growth temperature of CdSe nanocrystals in glass has been decreased and their growth time has been extended. In other words, a slow growth method has been performed to form pure CdSe nanocrystals in glass. The quantum size effect has been observed at their optical absorption spectra. Surface and longitudinal optical phonon modes of CdSe nanocrystals have been measured by using Raman spectroscopy. The refractive index change has been found as ~1.36×10-4 for CdSe nanocrystals with a diameter of ~3.93 nm. [ABSTRACT FROM AUTHOR]

Nanocrystalline (NC) materials are intrinsically unstable against grain growth. Significant research efforts have been dedicated to suppressing the grain growth by solute segregation, including the pursuit of a special NC structure that minimizes the total free energy and completely eliminates the driving force for grain growth. This fully stabilized state has been predicted theoretically and by simulations but is yet to be confirmed experimentally. To better understand the nature of the full stabilization, we propose a simple two-dimensional model capturing the coupled processes of grain boundary (GB) migration and solute diffusion. Kinetic Monte Carlo simulations based on this model reproduce the fully stabilized polycrystalline state and link it to the condition of zero GB free energy. The simulations demonstrate the emergence of a fully stabilized state by the divergence of capillary wave amplitudes on planar GBs and by fragmentation of a large grain into a stable ensemble of smaller grains. The role of solute diffusion in the full stabilization is examined. Possible extensions of the model are discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Based on the delocalized of melting criterion, a relatively simple analytical (i.e., without computer simulation) method for calculating the Lindemann ratio is proposed. It is shown that for classical single-component solids (in which the melting point (T m) is greater than the Debye temperature (Θ): T m /Θ > 1.5), the Lindemann ratio is determined only by the packing coefficient of the structure. Calculations for various structures of classical solids (both crystalline and amorphous) showed good agreement with the estimates of other authors. For quantum single-component crystals (in which T m /Θ < 0.4), the Lindemann ratio is determined not only by the crystal structure, but also by the Θ/ T m function. Therefore, when passing from the classical to the quantum area, the T m (Θ) function changes its functional dependence. It was shown that for quantum crystals, the Lindemann ratio decreases with increasing pressure along the melting line. For quantum nanocrystals, the Lindemann ratio increases with an isobaric decrease in a nanocrystal size. At this, the more noticeably the shape of the nanocrystal deviates from the energy-optimal shape, the greater the sized increase in the Lindemann ratio. Therefore, the use of the Lindemann criterion to study the melting of quantum crystals (as they tried to when studying the melting of atomic metallic hydrogen) showed incorrect results. The dependence of the Lindemann ratio (LE) on the ratio of the melting point (Tm) to the Debye temperature (Θ) for various structures of solid. [Display omitted] • Lindemann ratio, which can be applied to classical and quantum solids is proposed. • Lindemann ratio (LR) for crystalline and amorphous classical solids is calculated. • For quantum crystals the LR decreases at the pressure increase along the melting line. • For quantum nanocrystals the LR increases with the decrease in the nanocrystal size. • It is incorrect to use the Lindemann criterion to the melting of quantum crystals. [ABSTRACT FROM AUTHOR]

In this study, strontium titanate (SrTiO 3) nanoparticles were obtained utilizing a one-step supercritical continuous solvothermal synthesis process involving acetylacetonate precursors for both strontium and titanium cations instead of the historical alkoxide ones. These precursors are expensive, difficult to access (especially for strontium isopropoxyde) and inadequately stable, forcing the use of a glove box and controlled atmospheres, which is not the case for acetylacetonates. Pure SrTiO 3 nanoparticles with a crystallite size of roughly 20 nm were successfully synthesized. In addition to the cubic structure of SrTiO 3 , FTIR revealed surface functions that are typical of "wet" processes, while Raman spectroscopy showed the activation of non-centrosymmetric modes brought on by non-linear contributions. The nanoparticles show a faceted shape and are stable at elevated temperatures (up to 800 °C), according to in-situ high temperature XRD measurements. However, due to a chemical deficiency in strontium, titanium dioxide (TiO 2) phases are formed at higher temperatures. In-situ high temperature HRTEM investigations showed the existence of two populations of particles, with a better stability for the bigger-sized particles after thermal treatment as well as the sintering and restructuring of the smallest ones. Also, the microscopy results suggest the possibility of a chemical inhomogeneity within the crystallites. Overall, this study offers important new knowledge on the physicochemical characteristics of the synthesized SrTiO 3 nanoparticles and their thermal stability using a novel supercritical continuous solvothermal approach based on the use of acetylacetonate precursors. [Display omitted] • Strontium titanate (SrTiO 3) is a fascinating material for "green" applications. • A new and simple supercritical solvothermal flow synthesis using acetylacetonate precursors. • Unique metastable nanoparticles of strontium titanate with unusual thermal stability. • In-situ TEM investigation of metastable nanoparticles of strontium titanate evolution. [ABSTRACT FROM AUTHOR]

Grain size of GW103K Mg alloy powder were markedly refined to about 45 nm from 20 μm by an optimized hydrogenation-disproportionation-desorption-recombination (HDDR) process. By changing temperature, hydrogen pressure and time, the optimum hydrogenation conditions are explored by orthogonal design. Then the complete dehydrogenation process was determined by using single factor control variables. Furtherly, the HDDRed powder was spark plasma sintering (SPS) sintered and hot extruded to prepare GW103K alloy bulk. XRD, OM, scanning electron microscopy (SEM), and transmission electron microscope (TEM) were used to analyze the phase transformation and microstructure evolution, based on which the grain refining mechanism during the HDDR were discussed. The optimum HDDR parameters for preparing nanocrystalline Mg alloy powders are hydriding at 550 °C under 5 MPa hydrogen pressure for 24 h and dehydriding at 550 °C for 8 h in vacuum. The nanocrystalline GW103 alloy presents a notable dimensional stability and the grain size of the alloy bulk is 43 nm after SPS and hot extrusion. As a result, the nanocrystalline GW103K specimens exhibit excellent mechanical properties compared to the coarse-grained counterparts. Especially, the nanocrystalline GW103K alloy has a tensile elongation of 21.1% which is much more than those of the as-cast and as-extrusion alloys. [ABSTRACT FROM AUTHOR]