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Supported metal catalysts are extensively used in industrial and environmental applications. To improve their performance, it is crucial to identify the most active sites. This identification is, however, made challenging by the presence of a large number of potential surface structures that complicate such an assignment. Often, the active site is formed by an ensemble of atoms, thus introducing further complications in its identification. Being able to produce uniform structures and identify the ones that are responsible for the catalyst performance is a crucial goal. In this work, we utilize a combination of uniform Pd/Pt nanocrystal catalysts and theory to reveal the catalytic active-site ensemble in highly active propene combustion materials. Using colloidal chemistry to exquisitely control nanoparticle size, we find that intrinsic rates for propene combustion in the presence of water increase monotonically with particle size on Pt-rich catalysts, suggesting that the reaction is structure dependent. We also reveal that water has a near-zero or mildly positive reaction rate order over Pd/Pt catalysts. Theory insights allow us to determine that the interaction of water with extended terraces present in large particles leads to the formation of step sites on metallic surfaces. These specific step-edge sites are responsible for the efficient combustion of propene at low temperature. This work reveals an elusive geometric ensemble, thus clearly identifying the active site in alkene combustion catalysts. These insights demonstrate how the combination of uniform catalysts and theory can provide a much deeper understanding of active-site geometry for many applications.

Brain metastasis is a common and serious complication of breast cancer, which is commonly associated with poor survival and prognosis. In particular, the treatment of brain metastasis from triple-negative breast cancer (BM-TNBC) has to face the distinct therapeutic challenges from tumor heterogeneity, circulating tumor cells (CTCs), blood–brain barrier (BBB) and blood–tumor barrier (BTB), which is in unmet clinical needs. Herein, combining with the advantages of synthetic and natural targeting moieties, we develop a “Y-shaped” peptide pVAP-decorated platelet-hybrid liposome drug delivery system to address the all-stage targeted drug delivery for the whole progression of BM-TNBC. Inherited from the activated platelet, the hybrid liposomes still retain the native affinity toward CTCs. Further, the peptide-mediated targeting to breast cancer cells and transport across BBB/BTB are demonstrated in vitro and in vivo. The resultant delivery platform significantly improves the drug accumulation both in orthotopic breast tumors and brain metastatic lesions, and eventually exhibits an outperformance in the inhibition of BM-TNBC compared with the free drug. Overall, this work provides a promising prospect for the comprehensive treatment of BM-TNBC, which could be generalized to other cell types or used in imaging platforms in the future.

In this study, we prepared a folic acid-functionalized SMMC-7721 liver cancer cell membrane (CM)-encapsulated paclitaxel nanocrystals system (FCPN) for hepatoma treatment. Transmission electron microscopy (TEM) characterization showed that FCPN was irregular spherical shapes with a particle size larger than 200 nm and a coated thickness of approximately 20 nm. In an in vitro release experiment, FCPN indicated a slowly release effect of paclitaxel (PTX). Cell experiments demonstrated that FCPN was taken up by SMMC-7721 cells and significantly inhibited the proliferation of SMMC-7721 cells, which illustrated that FCPN had good targeting ability compared with PN and CPN. According to the results of in vivo animal experiments, FCPN significantly inhibited tumor growth. Tissue distribution experiments proved that FCPN could accumulate significantly in tumor tissues, which further explained why FCPN had good targeting ability. These results clearly suggested that folate-functionalized homotypic CM bionic nanosystems might represent a very valuable method for liver cancer treatment in the future.

Chronic wounds have affected more than 6 million people, especially diabetic populations. Various antimicrobial substances have been added to nanocellulose-based wound dressing to inhibit microbial growth. However, the substances triggered multiple adverse implications on humans. In this communication, we have developed a ferulic acid-grafted cellulose nanocrystal film as a potential antimicrobial material for wound dressing development. Needle-like cellulose nanocrystals, with an average length of 159 ± 31 nm, were extracted from medical-grade cotton using the acid hydrolysis method. A combination of cellulose nanocrystals, polyvinyl alcohol (PVA) and ferulic acid has generated a soft, sturdy, flexible, elastic and non-ductile film. It absorbed a large amount of exudates by presenting a swelling ratio of 774 ± 57%. The release of ferulic acid achieved a plateau at 20 h, with a total release of 75.4 ± 7.9% from the developed film. The ferulic acid-grafted cellulose nanocrystal film inhibited the growth of 2 Gram-positive bacteria, 3 Gram-negative bacteria and 1 yeast. During the Hohenstein challenge and wash durability, the developed film retained its antimicrobial efficiency by reducing up to 82% microbial growth even after 20 washes. The findings exposed that the ferulic acid-grafted cellulose nanocrystal film is effective in combating wound pathogens and ideal for dressing development.

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]

A straightforward and inexpensive electrophoretic method for obtaining environment-friendly nanocrystalline piezo layers from Rochelle salt (RS) is presented here. The electrophoretic deposition process includes the formation of nanocrystals by precipitation of Rochelle salt/water solutions in ethanol (anti-solvent method) under the influence of a high electric field. A nanoporous anodic aluminum oxide membrane is used to separate the electrochemical cell into two chambers. The composition of the RS:H2O:EtOH mixture and the spatial separation of the process of precipitation from electrophoretic deposition allow control of the nanocrystal size and the uniformity of the layer. The reaction kinetics, the morphology, and the piezo response to the resulting layers are all investigated. The best samples were obtained at RS:H2O:EtOH ratio 1:22.5:37.5. Under these conditions, the nanocrystals are preferentially oriented on the aluminum substrate and form a dense and homogeneous layer. Although the obtained structure is polycrystalline, the resulting piezo effect is 1120 pC/N, which is comparable to inorganic monocrystals and piezoceramics. This allows the use of electrophoretically deposited polycrystalline piezo layers in applications such as energy harvesting. [ABSTRACT FROM AUTHOR]

Persistent phosphorescence eliminates the need for light excitation and thus avoids the issue of autofluorescence, holding great promise in various fields. To achieve bright phosphorescence emission, many methods were developed to confine most organic persistent phosphorescent materials in a rigid environment aiming to quench nonradiative relaxation pathways; among them, the nanocrystal method is a good candidate which can rigidify the molecules as well as offer the desirable water dispersity and size for further bioapplications. However, the current efficient preparation of phosphorescent nanocrystals still remains challenging. This study reports an efficient microemulsion-based method for the fabrication of phosphorescent nanocrystals with a desired diameter in the nanosize range (below 200 nm), a high phosphorescence quantum yield of about 6.5%, and ultralong persistent phosphorescence to the timescale after the removal of the external light source, making it easy for the commercial imaging system to detect, which is suitable for practical bioimaging. Furthermore, the synthesized nanocrystals with biocompatibility were utilized directly for in vitro imaging, showing effective cellular uptake and bright phosphorescence emission, which provides a reasonable strategy to develop a phosphorescent nanocrystal for application. [ABSTRACT FROM AUTHOR]

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To get a systematic understanding about dependence of deposition conditions on properties of Gd films, a series of Gd films were prepared under different Ar gas pressures: 0.5, 0.7, 1.0, and 1.5 Pa, and another series of Gd films were prepared under different substrate temperatures: 25, 100, 200, 350, and 500 °C. The effects of the deposition time, Ar pressure, and substrate temperature on microstructures and crystal orientation were investigated by grazing-incidence X-ray diffraction (GIXRD) and transmission electron microscopy (TEM). The experimental results show that low Ar pressure and plenty deposition time will contribute to the formation of Gd hcp phase, which has better magnetic properties such as higher Curie temperature and bigger magnetic moment, and high substrate temperature can diminish the inner stress in Gd films and promote lattice parameters closer to those of the ideal Gd hcp-structure. [ABSTRACT FROM AUTHOR]

Latuda® is an oral tablet approved by the US Food and Drug Administration (FDA) for the treatment of schizophrenia. However, the clinical efficacy of Latuda® is compromised by patient noncompliance due to frequent daily administration, especially for patients experiencing severe schizophrenia, whose medication is often needed for several months to years. Hence, developing a long-acting injectable formulation of lurasidone is urgently needed. Herein, a poorly water-soluble lurasidone pamoate (LP) salt was synthesized via the facile ion pair-based salt formation technology. The solubility of LP was decreased by 233 folds compared with that of lurasidone hydrochloride (LH). Furthermore, suspensions of LH and LP with three different particle sizes, including 400 nm small-sized nanocrystals (SNCs), 4 μm medium-sized microcrystals (MMCs), and 15 μm large-sized microcrystals (LMCs) were prepared and characterized by powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC). The in vitro release results showed that particle sizes had great effects on the sustained release of LH, where large-sized particles exhibited superior sustained release than the smaller ones. Besides, LP suspensions exhibited better sustained release than LH suspensions at the same size scale. Moreover, the pharmacokinetics showed that LP LMCs produced an extended in vivo intramuscularly injectable profile for up to 45 days, which was 10 days longer than that of the LH LMCs. Our findings demonstrated that particle size had appreciable impacts on drug sustained release and provided valuable knowledge for the rational design of optimized micronized suspensions for long-acting injectables. [ABSTRACT FROM AUTHOR]

Abstract 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.

Structural changes of Er- or Yb-ion doped LiNbO3 (LN) nanocrystals were studied in relation to the high-energy ball milling process. The evolution of the size of the particles and the formation of different phases were followed by dynamic light scattering and X-ray diffraction measurements, while the electronic transitions of rare-earth (RE) ions were investigated by absorption spectroscopy in the infrared spectral range. During the milling process, RE ions left the crystal lattice and an RE2O3 phase appeared to an increasing extent next to the LN. The change in the absorption spectra and the phases formed during the grinding process were found to be very similar for both investigated RE ions and were independent of their original concentration in the starting crystal samples. The extent of the RE loss was found to be 90% after 100 min of wet grinding.

The use of nanocrystal technology to manufacture drug delivery systems intended to enhance therapeutic efficacy has attracted the attention of the pharmaceutical industry. However, the clinical application of nanocrystal drugs for injection is restricted by Ostwald ripening and the large-scale use of stabilizers such as polysorbate and lecithin, which have potential toxicity risks including hemolysis and allergies. Here, we designed an amorphous nanocrystal drug complex (IHNC), which is stabilizer-free and composed of indocyanine green (ICG) framework loading with a chemotherapeutic agent of 10-hydroxycamptothecin (HCPT). Considering the possibility of industrial manufacturing, IHNC was simply prepared with the assistance of ferric ion (III) via supramolecular assembly strategy. The theoretical result of Materials Studio simulation indicated that the prepared ICG-Fe(III) framework showed a stable spherical structure with the appropriate cavity for encapsulating the two drugs of HCPT and ICG with equal mass ratio. The IHNC was stable at physiological pH, with excellent PTT/PDT efficacy, and in vivo probing characteristics. The nanoscale size and reductive stimuli-responsiveness can be conducive to drug accumulation into the tumor site and rapid unloading of cargo. Moreover, such combination therapy showed synergistic photo/chemotherapy effect against 4T1 breast cancer and its tumor inhibition rate even up to 79.4%. These findings demonstrated that the nanocrystal drug delivery strategy could avoid the use of stabilizers and provide a new strategy for drug delivery for combination therapy.

Nanomaterials have been widely researched for use in construction materials. Numerous studies demonstrate that nanomaterials in small quantities can significantly improve the macroscopic properties of cement paste, mortar, or concrete through various mechanisms. Nanomaterials retrieved from biomass sources have recently gained particular research interest due to remarkable structural properties and the source material’s abundance and renewability. Cellulose and chitin are the most abundant polysaccharides in nature; thus, they are candidates for nanomaterials extraction as multifunctional additives in cementitious systems. In recent years, cellulose nanomaterials in cementitious composites have been extensively investigated, but chitin nanomaterials and starch derivatives for cement and concrete are still emerging research areas. This review article starts with an overview of polysaccharide nanomaterials’ (PNMs) physicochemical properties as a result of different chemical and mechanical extraction processes. Next a brief overview of cement hydration chemistry and microstructure and the interfacial interactions between the cement and the various surface chemical functionalities of PNMs are discussed. Then, the key mechanisms governing the cement strength enhancement by PNMs, such as bridging, nucleating and filling effect, and internal curing, are described. Finally, the impacts of PNMs on other properties of the cement are discussed.

Fei Peng,1 Jing Liu,1,2 Yujun Zhang,1,2 Guoyan Zhao,1,2 Deying Gong,1,2 Liu He,1,2 Wensheng Zhang,1,2 Feng Qiu1,2 1Laboratory of Anesthesia and Critical Care Medicine, Department of Anesthesiology, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, 610041, People’s Republic of China; 2National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, 610041, People’s Republic of ChinaCorrespondence: Feng Qiu; Wensheng Zhang, Email fengqiu@scu.edu.cn; zhang_ws@scu.edu.cnIntroduction: Ropivacaine as a conventional local anesthetic has been used more and more frequently in the treatment of postoperative pain, but its analgesic effect can only last for several hours. In order to fulfill the clinic requirement for long-term analgesia, a long-acting ropivacaine nanocrystal formulation was fabricated through the interaction between ropivacaine and a self-assembling peptide.Methods: Transmission electron microscopy, dynamic light scattering, circular dichroism and fluorescence spectrometry were used to examine the structural changes caused by the interaction between ropivacaine and the peptide. Scanning electron microscopy, dynamic light scattering, Fourier transform infrared spectrometry, X-ray diffraction and optical microscopy were used to characterize the ropivacaine-peptide nanocrystal. In vitro drug release and pharmacokinetics study were conducted to evaluate the slow-release profile of the nanocrystal formulation. A rodent cutaneous trunci muscle reflex model was used to evaluate the nociceptive blockade effects, and histological analysis was used to evaluate the local toxicity. A rodent plantar incisional pain model was used to evaluate the analgesic effect.Results: Soluble ropivacaine monomers interacted with the Q11 peptide through π-π stacking and remolded its self-assembling structure, leading to the formation of drug/peptide nanoparticles which could be mineralized to form drug/peptide nanocrystals by adjusting the pH. Under physiological condition, the nanocrystals could release free ropivacaine slowly. As evaluated in rodent models, the anesthetic and analgesic effects of this formulation were significantly extended without causing toxicity.Conclusion: Based on the interaction between ropivacaine and Q11, a controllable biomineralization process could be induced to obtain homogeneous nanocrystals, which could be used as an injectable long-acting analgesic formulation. This crystallization strategy utilizing the peptide-drug interaction also provided a promising pathway to fabricate long-acting formulations for many other small molecular drugs.Keywords: self-assembling peptide, nanocrystal, local anesthetics, π-π stacking, slow release, long-acting analgesia

ABSTRACT Bacterial spot caused by Xanthomonas spp. (X. vesicatoria, X. euvesicatoria pv. euvesicatoria, X. euvesicatoria pv. perforans, and X. hortorum pv. gardneri) may result in significant losses for tomato crops. Simonkolleite nanoparticles (SK-NPs) has been indicated as a novel approach for plant disease control. The objective of this work was to evaluate SK-NPs (ZnOCl, ZnOCl:Ag, and ZnOCl:Cu at different concentrations) for the in vitro inhibition of X. hortorum pv. gardneri, determining the time of exposure of the products for the bacterial death; the reduction of bacteria recovery on inoculated seeds, and their efficacy to reduce bacterial spot severity in plant. The growth inhibition was evaluated by inhibition zone in culture medium plates, when the diameter of the inhibition zone was measured. The period of exposure of the products to the bacterial suspension tested were 1, 2, 3, 4, or 5 h. Tomato inoculated seeds were treated with SK-NPs. In plant, the preventive and curative effects were evaluated by applying the products two days before or after inoculation, respectively. Disease severity was evaluated and the area under the disease progress curve (AUDPC) was calculated. ZnOCl:Ag, ZnOCl:Cu, and ZnOCl inhibited bacterial growth, and the 5 h exposure time was necessary to reduce bacterial growth. ZnOCl:Ag, and ZnOCl:Cu reduced the bacteria presence in the seeds, and did not affect the seed germination. Both products reduced the AUDPC in the preventive application. The use of SK-NPs ZnOCl:Ag and ZnOCl:Cu showed to be promising to manage tomato bacterial spot.

Nanocrystal suspensions have been introduced to overcome the low bioavailability of poorly water-soluble drug compounds by increasing the dissolution rates. For both injection- and inhalation-based administrations it is important that the suspensions are sterile to eliminate any adverse events from potential microbial infections, but it has proven very challenging to sterilize nanocrystal suspensions without aggregation or degradation. Here we describe bead milling methodology to generate ultrafine nanocrystal suspensions of several poorly water-soluble drug compounds that can be passed through 0.22 ​μm sterilization filters. The most important factors for successful milling to ultrafine nanocrystal suspensions are the stabilizer excipients combined with fine milling-beads. The sodium dodecyl sulphate (SDS) or docusate sodium/aerosol OT (AOT) combined with Polyvinylpyrrolidone K30 (PVP) stabilizer systems and 1,2-Dipalmitoryl-sn-Glycero-3-Phosphoethanolamine conjugated methoxy Polyethylene Glycol (DPPE) and 1,2-Distearoyl-sn-Glycero-3-Phosphoethanolamine conjugated methoxy Polyethylene Glycol (DSPE) surfactants were among the best stabilizer excipients studied.

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]

Going down the particle size to nanodomain opens up innovative allies to expedite the physical and chemical properties of materials, and in turn, facilitates the manipulation of their catalytic propensity. Herein, we provide a succinct perspective of the wide spectrum of nanoparticles (NPs) in catalysis highlighting the underlying chemistry of different aspects, the introspective thread connecting them, and the ways to devise operando algorithms for exploiting such inter-connected systems. Following an introductory section discussing the generic miens of NPs, we went on to discuss the role of nanocrystals, especially various crystal facets and morphological anomalies in catalysis. The electronic shuttling involved in these catalysis vis-à-vis surface plasmon effect, Mott–Schottky contact, and Z-scheme systems, all in the nanodomain, was then explained. Following this, we introduced the concept of "Soft Matter" and "Active Matter", essentially the ones exploiting previously discussed chemistry, and explained the role of their in situ morphological precedence and stimuli-induced motility in catalysis. Finally, the emerging concept of Operando Systems Chemistry Algorithm (OSCA) was instituted discussing the devising strategies of tandem compartmentalized chemical arrays as individual algorithm analogs to sequentially impact the properties of aforementioned soft and active matters for targeted catalytic assays. [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]

Two continuum models are proposed for predicting stress fields and elastic properties of nanosized diamond monocrystals. The first model is a boundary value problem of the elasticity theory formulated for a sphere with a thin shell, which ensures consideration of the effect of the free surface energy on the elastic behavior of a diamond nanocrystal. In the second model, the surface energy is taken into account through the boundary condition in accordance with the Gurtin–Murdoch theory of material surfaces. The geometric and material parameters of the models are determined by comparison with the results of classical molecular dynamics. A parametric analysis of the developed models is carried out, and the trends in the influence of the nanoparticle size on the lattice parameter, stress concentration, and bulk elastic modulus of diamond are determined. [ABSTRACT FROM AUTHOR]

Quinoa starch nanocrystals (QSNCs), obtained by acid hydrolysis, were used as a reinforcing filler in cassava starch films. The influence of QSNC concentrations (0, 2.5, 5.0, 7.5 and 10%, w/w) on the film's physical and surface properties was investigated. QSNCs exhibited conical and parallelepiped shapes. An increase of the QSNC concentration, from 0 to 5%, improved the film's tensile strength from 6.5 to 16.5 MPa, but at 7.5%, it decreased to 11.85 MPa. Adequate exfoliation of QSNCs in the starch matrix also decreased the water vapor permeability (~17%) up to a 5% concentration. At 5.0% and 7.5% concentrations, the films increased in roughness, water contact angle, and opacity, whereas the brightness decreased. Furthermore, at these concentrations, the film's hydrophilic nature changed (water contact angle values of >65°). The SNC addition increased the film opacity without causing major changes in color. Other film properties, such as thickness, moisture content and solubility, were not affected by the QSNC concentration. The DSC (differential scanning calorimetry) results indicated that greater QSNC concentrations increased the second glass transition temperature (related to the biopolymer-rich phase) and the melting enthalpy. However, the film's thermal stability was not altered by the QSNC addition. These findings contribute to overcoming the starch-based films' limitations through the development of nanocomposite materials for future food packaging applications. [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]

Brain metastasis is a common and serious complication of breast cancer, which is commonly associated with poor survival and prognosis. In particular, the treatment of brain metastasis from triple-negative breast cancer (BM-TNBC) has to face the distinct therapeutic challenges from tumor heterogeneity, circulating tumor cells (CTCs), blood–brain barrier (BBB) and blood–tumor barrier (BTB), which is in unmet clinical needs. Herein, combining with the advantages of synthetic and natural targeting moieties, we develop a "Y-shaped" peptide pVAP-decorated platelet-hybrid liposome drug delivery system to address the all-stage targeted drug delivery for the whole progression of BM-TNBC. Inherited from the activated platelet, the hybrid liposomes still retain the native affinity toward CTCs. Further, the peptide-mediated targeting to breast cancer cells and transport across BBB/BTB are demonstrated in vitro and in vivo. The resultant delivery platform significantly improves the drug accumulation both in orthotopic breast tumors and brain metastatic lesions, and eventually exhibits an outperformance in the inhibition of BM-TNBC compared with the free drug. Overall, this work provides a promising prospect for the comprehensive treatment of BM-TNBC, which could be generalized to other cell types or used in imaging platforms in the future. A "Y-shaped" peptide pVAP-decorated platelet-hybrid liposomes drug delivery system is developed to address the all-stage targeted drug delivery for the brain metastatic triple-negative breast cancer. [Display omitted] [ABSTRACT FROM AUTHOR]

The optimization of the parameters of the solvothermal synthesis of lithium niobate (LiNbO3, LN) nanocrystals from Nb2O5 and LiOH was performed. The effects of polyol media, reaction time and Li excess of the starting reagents were investigated. According to the X-ray diffraction phase analysis, Li3NbO4 and Nb2O5 were also detected besides the LN phase in many samples depending on the ratio of the starting components and the reaction time. The best yield and the most homogeneous LN phase was prepared by using diethylene glycol medium with a Li/Nb ratio of 1.5 and a 72 h reaction time. The size and the shape of the LN particles were characterized by scanning electron microscopy. The particle size distribution was narrow and under 100 nm for all cases. [ABSTRACT FROM AUTHOR]

Abstract The production of colors by plasmonic nanostructures is an attractive prospect over dyes as they allow ultra‐high resolution, non‐fading colors. Typical techniques for producing plasmonic color patterns such as by electron beam or ion beam lithography are expensive, slow and not well scalable. This work demonstrates a simple, lithography‐free technique for producing plasmonic colors using a silver nanocube (AgNC) based nanoparticle‐over‐mirror (NPoM) system with thermally‐generated colors. AgNC's are deposited over a metal (Au or Ag) film with a polystyrene (PS) dielectric spacer. Upon heating the system past the glass‐transition temperature of PS, the AgNC embed into the polymer, reducing the AgNC/metal film distance. This results in a strong gap‐plasmon that can shift over 200 nm across the visible spectrum during the process. The thermal embedment of AgNC in NPoM systems is tunable across the visible range, producing wide, distinct color palettes depending on the metal film used. This technique can potentially be applied to plasmonic color‐patterning systems to produce high‐resolution microscale or nanoscale patterns over a large area.

Metal nanocrystals exhibit unique properties due to their high surface-to-volume ratio and have great potential for applications in the fields of electronics, magnetics, optics and catalysis. However, their high specific surface area leads to easy coarsening in operation, which may greatly degrade their performances, especially when they are exposed to various chemical environments or at high temperatures. Therefore, the direct visualization of nanocrystals' structural evolution when they are coarsening is crucial to gain insight into the mechanism and develop more effective means to improve the size stability of nanocrystals. In this work, we investigated the structural evolution of Pt nanocrystals with sizes of ~ 4 nm on SiNx film in both oxidizing and reducing atmospheres at a moderate temperature (300оС) in the aberration-corrected environmental transmission electron microscopy (ETEM). The sizes of nanocrystals remain almost unchanged when annealed in the oxygen atmosphere with volatile PtOx formation on the surface, hindering nanocrystals sintering and leading to Pt loss. On the other hand, obvious coarsening of nanocrystals resulting from Ostwald-ripening and nanocrystal migration and coalescence was observed in the reducing atmosphere. Our findings reveal the dynamic structural evolution of nanocrystals in different atmospheres and provide possible ways to improve the size stability of nanocrystals.

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]

Catalytic remediation of industrial organic pollutants is considered effective mitigation of increasing risks from aqueous contaminations composed of hazardous substances. The need for in-situ environmental remediation is highly demanded to deal with organic contaminations from on-site, instant, and full-time treatment without the need to remove the contaminated sources for ex-situ remediation is highly demanded. In this work, by means of combining the strategies of daytime and dark degradation capabilities of organic dyes, the MoS 2 /Au@CuS hybrid catalysts resembling semiconductor/metal/semiconductor junction features underline the generation of hydroxyl radicals, and force to speed up the oxidative removal of organic dyes during light-on and light-off conditions in both scenarios. Decorations of CuS on hydrothermally synthesized MoS 2 /Au nanoflowers are prepared with the in-situ chemical reduction process. We reveal that such circumstance exists when programming the environment in the sequence of light-on/light-off conditions, which actively clicks the generation of H 2 O 2 and strategically accelerates the degradation kinetics, offering an additional opportunity for promoting catalytic degradation of hazardous organic dyes with whole-day feasibility. [Display omitted] • The facile synthesis of MoS 2 /Au@CuS catalysts and correlated band features are presented. • The hybrid photocatalysts demonstrate the fulltime capabilities of dye degradation. • The effective assessment of light-on/light-off treatment of organic dyes is realized. [ABSTRACT FROM AUTHOR]

• Compact crystalline material strain 0.290 %, lattice volume 68.353 Å3. • Almost 95.0 % silver phase and crystallinity 59.37 % • Lattice parameters α = β = γ = 90.0°, a = b = c = 4.08871 Å. • The average crystallite size was 32.12 nm. A highly crystalline phase of silver nanoparticles was successfully synthesized using silver nitrate as the precursor and trisodium citrate dihydrate as the chelating agent. Rietveld refinement analysis revealed that approximately 95.0 % of the synthesized material consisted of crystalline silver nanoparticles, with the remaining 5.0 % being unreacted starting material. XRD characterized the prominent crystalline phase, providing insights into lattice parameters were α = β = γ = 90.0°, a = b = c = 4.08871 Å; lattice strain 0.290 %, lattice volume 68.353 Å3 and average dislocation density 9.6 9 × 10-4 nm−2. The most intense diffraction peak was attributed to the (1 1 1) plane at 2θ = 38.18°. The average crystallite size was determined to be 32.12 nm, confirming the formation of crystalline silver nanoparticles. The specific surface area of the synthesized silver nanoparticles was 18 m2/g Notably, the synthesized silver nanoparticles exhibited a higher degree of crystallinity (59.35 %) compared to the standard silver nitrate (38.46 %), indicating a highly crystalline nature. The crystallographic data confirmed the successful synthesis of highly crystalline silver nanoparticles with improved crystallinity over the reference material. [ABSTRACT FROM AUTHOR]

• CM 2 A 8 synthesized by the simple, short-time, and inexpensive sol-gel method. • In solid-state route, growth of CM 2 A 8 described by two-dimensional nucleation. • In sol-gel route, growth of CM 2 A 8 described by chelation of citric acid and metal ions. • Sol-gel method leads to a better crystallinity and lower formation temperature. This study aims at the synthesis of a ternary phase crystal CaO.2MgO.8Al 2 O 3 (CM 2 A 8) in the Al-rich part of the ternary system CaO-Al 2 O 3 -MgO through two techniques: (1) sol–gel citrate and (2) solid-state reaction. Based on the measurement of particle size, density, phase analysis, nature of bounds, and microscopic observation, the effect of the processing technique on the crystal purity, crystallite size, and synthesis temperature of the as-prepared CM 2 A 8 powder was investigated. Phases analysis (XRD patterns) showed in the sol–gel citrate combustion method almost a single-phase material (calcium aluminate magnesium phases) at relatively lower temperatures while in the solid-state method as-prepared CM 2 A 8 powder with a small amount of spinel (MgAl 2 O 4 = MA) and calcium hexaaluminate (CaAl 12 O 19 = CA 6) secondary phases. The generated heat through the combustion of the reaction of ammonium nitrate and citrate-based complexes decreases the synthesis temperature of nanocrystalline CM 2 A 8 , and the CM 2 A 8 phase is formed at a temperature of 1400 °C. While growth mechanism in the solid-state reaction method adheres to the two-dimensional nucleation theory and a thick hexagonal flake known as CM 2 A 8 is produced at a temperature of 1700 °C. In comparison with the crystals synthesized by the solid-state reaction method, the powder density of the nanocrystals synthesized by a sol–gel combustion method exhibits higher values (3.54 g.cm−3 and 3.65 g.cm−3, respectively). Peak intensities in the 400–1000 cm−1 range, according to FTIR measurements, correspond to metal–oxygen–metal (M–O–M) bonds (vibrations of Al–O stretching in Mg–O–Al and Ca–O–Al), and they grow as the temperature rises from 200 °C to 1400 °C, indicating that CM2A8 was the crystal that was formed. The morphological analysis (FESEM) revealed that most of the agglomerate particles synthesized by the sol–gel citrate combustion remained within the range of 50–83 nm, while the particles synthesized by the had particles as 1 μm. The specific surface area synthesized CM 2 A 8 via the sol–gel method is in the range of 10–24 m2/g. The main advantages of the sol–gel citrate process are the high purity of the product, the narrow particle size distribution, and the achievement of uniform nanostructure at low temperatures. [ABSTRACT FROM AUTHOR]