Steel slag waste combined with melamine pyrophosphate as a flame retardant for rigid polyurethane foams

To explore the potential application of industrial waste, steel slag powder in combination with melamine pyrophosphate (MPP) was adopted to improve the flame retardancy of rigid polyurethane foam (RPUF). The incorporation of steel slag slightly reduced the thermal conductivity of the resulting flame-retardant RPUF samples. The addition of MPP and/or steel slag did not significantly alter the thermal stability in terms of T_-10% and T_max but did obviously increase the T_-50% value, suggesting the improved thermal resistance of the residues. The coaddition of MPP and steel slag into RPUF resulted in higher LOI values and lower peak heat release rates than the samples incorporating either MPP or steel slag alone. The superior flame retardancy could be attributed to MPP promoting char formation, which then acted as a barrier at the beginning of RPUF thermal decomposition; simultaneously, the thermally stable inorganics in the steel slag powder strengthened the thermal resistance of this char layer.     

Synergistic antidiabetic activity of ZnO nanoparticles encompassed by Urtica dioica extract

The present study aimed at producing ZnO nanoparticles using the leaf extract of nettle (Urtica dioica) as a medicinally valuable plant to maximize the antidiabetic property of ZnO while excluding the chemical pollution from the synthesis process. The properties of the ZnO-extract sample were uncovered by various techniques and compared to that produced without the extract (ZnO). The results of the surface, optical, and thermal studies disclosed the presence of the extract biomolecules over the ZnO-extract sample and was further confirmed by GC–MS analysis. The ZnO-extract was intraperitoneally injected to alloxan-induced diabetic rats and the effects on the serum levels of fasting blood glucose, insulin, high-density lipoprotein cholesterol, total cholesterol, and total triglyceride were assessed. The obtained results were then compared with the effects of ZnO, nettle leaf extract, and insulin on the same factors. Among all the examined treatments, the best antidiabetic performance was obtained in the rats treated by ZnO-U. dioica extract mainly owing to the great synergistic interaction between its constituents.     

Improving hydrothermal performance of hybrid nanofluid in double tube heat exchanger using tapered wire coil turbulator

Tapered wire coil insert is proposed as a novel enhancer in the double tube heat exchanger and experimental studies on Al₂O₃ + MgO hybrid nanofluid flowing under the turbulent condition are performed to investigate the hydrothermal characteristics. Effects of using tapered wire coil turbulator and hybrid nanofluid on the hydrothermal behaviors are examined for different coil configurations (Converging (C) type, Diverging (D) type and Conversing-Diverging (C-D) type) and hybrid nanofluid inlet temperatures and volume flow rates. Results show that D-type wire coil insert promotes better hydrothermal performance as compared to C-type and C-D type. Nusselt number and friction factor of hybrid nanofluid using D-type, C-D type and C-type wire coil inserts enhance up to 84%, 71% and 47%, and 68%, 57% and 46%, respectively than that of water in tube without insert. The entropy generation of hybrid nanofluid is lower than that of base fluid in all cases. The thermal performance factor for hybrid nanofluid is found more than one with all inserts. The thermal performance factor is observed a maximum of 1.69 for D-type coil. The study reveals that the hybrid nanofluid and tapered wire coil combination is promising option for improving the hydrothermal characteristics of double pipe heat exchanger.     

3D HCN nanotexture with synergistic effect of nickel and hole scavengers for enhancing photocatalytic H2 production: Role of morphology and influential parameters

Well-designed three-dimensional (3D) nanotextures of graphitic carbon nitride (g-C₃N₄), synthesized using template free single step method and mediated with nickel as a noble free metal, for solar hydrogen production, has been investigated. The photoactivity was investigated in a slurry type continuous flow photoreactor system by using different influential parameters such as hole scavengers, diffusion effects, time, and mass transfer. Compared to bulk g-C₃N₄, H₂ yield was increased with 3D hierarchical carbon nitride (HCN) nanotexture. The H₂ evolution rate was reached to 1310 µmol g^?1 h^?1 with optimized 2 % Ni loading to 3D HCN. This H₂ evolution rate was 19.8 and 24.9 times higher than it was generated using 3D HCN and g-C₃N₄, respectively. The special interlayer opening, more light penetration and suppressed charge carrier recombination were the main contributors for this photoactivity enhancement. Among the different influential parameters, lower viscosity, higher number of protons and less diffusion effects were promising to give significantly higher H₂ production. The stability of nanotextures was entirely dependent on the attached reactants over the nickel reactive sites, which was more promising for Triethanolamine (TEOA) than using methanol. This newly developed low-cost 3D HCN can be promising in solar energy conversion and other energy applications.     

Thermal properties of hierarchical YSZ and LZO ceramic microspheres with multi-scaled voids investigated by using theoretical,experimental and simulation methods

Heat transfer within ceramic feedstock powders is still unclear, which impedes optimization of the thermal and mechanical properties of the thermal sprayed coatings. The microspheres (yttria-stabilized zirconia YSZ and lanthanum zirconate LZO) were prepared via the electro-spraying assisted phase inversion method (ESP). The thermal properties of the two ESP microspheres and a commercial hollow spherical powder (HOSP) were investigated by using theoretical, experimental, and simulation methods. Thermal conductivity of the single microsphere was estimated via a novel nest model that was derived from the Maxwell-Eucken 1 and the EMT model. Thermal conductivity of a single YSZ/LZO-ESP microsphere prepared at 1100–1200 °C was within 0.36–0.75 W/m K, which was ～ 20 % lower than that of a single YSZ-HOSP microsphere with a similar porosity. Heat flux simulation showed that high tortuosity around the multi-scaled voids of the ESP microsphere led to a more efficient decrease in thermal conductivity compared with total porosity.     

Elucidation of the thermophysical mechanism of hexagonal boron nitride as nanofluids additives

This study systematically investigated the physicochemical characteristics of hexagonal boron nitride (h-BN) nanoparticles dispersed in polyalphaolefin 6 (PAO6) from a molecular level to explore the thermal stability of nano-lubricants. The nanoparticles were characterized via transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and energy-dispersive spectrometry (EDS) to analyze the chemical bonds, element distribution, and impurity. We not only theoretically reveal the rheological behavior of nano-lubricants but also propose precise models to predict the viscosity. Moreover, this study comprehensively analyzed the thermal stability of nano-lubricants under different gas environments through thermogravimetric analysis and revealed that the nanofluid thermal stability was improved owing to the small-size effect. The results show that the thermal conductivity of the nano-lubricants was significantly higher than that of PAO6. Finally, the mechanism of thermal property enhancement by the h-BN nanoparticles is revealed.     

Electrochemical treatment of soil-washing effluent with boron-doped diamond electrodes: A review

In recent years, electrochemical technologies have been widely used to remove contaminants at lab-scale and semi-pilot scale. Boron-doped diamond (BDD) electrodes have been considered as efficient materials for the abatement of persistent organic pollutants owing to their outstanding properties, such as rapid rates of electron-transfer for soluble redox systems, wide electrochemical potential window for water discharge reactions in aqueous and non-aqueous electrolytes, and high stability. Similar to other applications of electrochemical technology, wastes display medium to high ionic conductivity. Therefore, one of the applications highlighted for the electrolysis with these new electrodes is the treatment of soil-washing fluids, because in the polluted streams, washing of polluted soils provides a suitable conductivity to the effluent. In this context, this review summarizes the application of conductive diamond anodes for the electrochemical treatment of soil-washing effluents contaminated with different persistent organic pollutant such as pesticides, hydrocarbons, dyes, and organochlorine compounds, in single anodic oxidation processes and in other more complex processes such as electro-Fenton, photoelectrolysis, or sonoelectrolysis. Finally, the challenges and future research directions of electrochemical technology are discussed and outlined at pilot and prototype scale.     

Synergistic enhancement of thermal conductivity between SiCw and h-BN in MVQ-based composite

Thermally conductive and electrically insulating h-BN/MVQ and h-BN/SiCw/MVQ composites were prepared by internal mixing and two roll mixing, using 1-dimensional (1D) silicon carbide whiskers (SiCw) and 2-dimensional (2D) hexagonal boron nitride flakes (h-BN) as fillers, and methyl vinyl silicone rubber (MVQ) as polymer matrix. Surface modification of 1?D SiCw and 2?D h-BN was characterized by Fourier transform infrared spectroscopy (FT-IR) and contact angle analysis. Morphology, thermal conductivity and dielectric constant of h-BN/MVQ and h-BN/SiCw/MVQ were studied. The results indicated that surface modified h-BN and SiCw could be uniformly distributed in MVQ matrix. At the same volume filler loading, thermal conductivity of h-BN/SiCw/MVQ ternary composite was higher than that of h-BN/MVQ binary composite. When part of 2?D h-BN was instead of 1?D SiCw, there was synergistically enhanced effect between 1?D SiCw and 2?D h-BN for thermal conductivity. When volume ratio of h-BN/SiCw was 8/2, thermal conductivity of h-BN/SiCw/MVQ was higher than that of other ratio. Thermal conductivity of h-BN/SiCw/MVQ composite with different volume ratio was linearly fit with Agari’ model.     

Characterization of solid-electrolyte/active-material composite particles with different surface morphologies for all-solid-state batteries

In all-solid-state lithium-ion batteries (ASS-LIBs), the electrode structure is an important factor that determines the battery performance; in particular, the formation of contact interface between the active material (AM) and solid electrolyte (SE) is an important issue associated with ASS-LIBs. Although we previously reported the formation of interfacial contacts between AM and SE by dry coating, the influence of the surface morphologies of composite particles on the performance of ASS-LIB was not revealed. In this study, we investigated the effects of the surface morphologies of composite particles on the performance of ASS-LIB. The surface morphologies of composite particles changed from “discrete” to “continuous” as the dry coating progressed. The cell prepared with composite particles showed higher ionic conductivity due to well-percolated ionic path than that prepared with simple mixture. Comparing the composite particles with different surface morphologies, the cell prepared with discrete-coating particles showed lower internal resistance due to higher ionic/electrical conductivity than that prepared with continuous-coating particles. Further, the cells prepared with discrete- and continuous-coating particles showed the highest charge and discharge capabilities, respectively. The results suggest that the contact areas of AM-SE and AM-AM were critical structural factors for the discharge and charge rate capability, respectively.     

Recent breakthroughs and perspectives of high-energy layered oxide cathode materials for lithium ion batteries

Ni-rich layered oxides (NRLOs) and Li-rich layered oxides (LRLOs) have been considered as promising next-generation cathode materials for lithium ion batteries (LIBs) due to their high energy density, low cost, and environmental friendliness. However, these two layered oxides suffer from similar problems like capacity fading and different obstacles such as thermal runaway for NRLOs and voltage decay for LRLOs. Understanding the similarities and differences of their challenges and strategies at multiple scales plays a paramount role in the cathode development of advanced LIBs. Herein, we provide a comprehensive review of state-of-the-art progress made in NRLOs and LRLOs based on multi-scale insights into electrons/ions, crystals, particles, electrodes and cells. For NRLOs, issues like structure disorder, cracks, interfacial degradation and thermal runaway are elaborately discussed. Superexchange interaction and magnetic frustration are blamed for structure disorder while strains induced by universal structural collapse result in issues like cracks. For LRLOs, we present an overview of the origin of high capacity followed by local crystal structure, and the root of voltage hysteresis/decay, which are ascribed to reduced valence of transition metal ions, phase transformation, strains, and microstructure degradation. We then discuss failure mechanism in full cells with NRLO cathode and commercial challenges of LRLOs. Moreover, strategies to improve the performance of NRLOs and LRLOs from different scales such as ion-doping, microstructure designs, particle modifications, and electrode/electrolyte interface engineering are summarized. Dopants like Na, Mg and Zr, delicate gradient concentration design, coatings like spinel LiNi_0.5Mn_1.5O₄ or Li₃PO₄ and novel electrolyte formulas are highly desired. Developing single crystals for NRLOs and new crystallographic structure or heterostructure for LRLOs are also emphasized. Finally, remaining challenges and perspectives are outlined for the development of NRLOs and LRLOs. This review offers fundamental understanding and future perspectives towards high-performance cathodes for next-generation LIBs.     

pH-responsive dual-functional hydrogel integrating localized delivery and anti-cancer activities for highly effective therapy in PDX of OSCC

As one of the most promising localized drug delivery systems for enhancing therapeutic efficacy and reducing systemic toxicity, supramolecular hydrogels self-assembled from natural products have recently attracted tremendous attention. However, the intricate drug loading process, limited drug entrapment efficacy, and lack of stimulus responsiveness considerably impede their potential for biological applications and raise the need for advanced hydrogel-based delivery systems. Therefore, the development of updated materials that integrate localized delivery and drug activity into a single system is extremely desired and has great potential to overcome the aforementioned shortcomings. In this study, a pH-responsive dual-functional isoG-based supramolecular hydrogel with both localized delivery and anti-cancer activity in one molecule is successfully developed in one pot by following a simple and green procedure. The isoguanosine-phenylboronic-guanosine (isoGPBG) hydrogel exhibits exceptional stability (more than one year), outstanding pH-responsiveness and excellent sustained release capability. Both in vitro and in vivo experiments demonstrate that the isoGPBG hydrogel not only shows acceptable biocompatibility and biodegradability but also significantly inhibit tumor growth (approximately 60% inhibition of tumor growth) and improve overall survival, especially in preclinical patient-derived xenograft (PDX) model of oral squamous cell carcinoma (OSCC). Therefore, the isoGPBG hydrogel, to the best of our knowledge, is the first example of pH-responsive dual-functional isoG-based supramolecular hydrogel integrating localized delivery and anti-cancer activity in one molecule. It is implied that the isoGPBG hydrogel could act as a smart dual-functional localized delivery system in the future for clinical cancer therapy.     

Heat absorption characteristics of gas in a solar fluidized bed receiver with carbon nanotubes

Carbon nanotubes (CNTs) have been proposed as new candidate particles to enhance the utilization efficiency of solar energy in solar fluidized bed receiver (SFBR) for solar air heating in low- and mid-temperature ranges. Heat absorption characteristics of the CNTs have been determined in a SFBR (50 mm i.d. X 150 mm high). Two types of experimental particles were used which consisted of multi-walled CNTs with different nanotube shapes, such as entangled CNTs (ENCNTs) and vertically aligned CNTs (VACNTs). The particle dynamics and heat absorption characteristics of CNTs were studied and compared with those of silicon carbide (SiC), a conventional particle. CNTs showed lower pressure fluctuation with relatively uniform particle behavior in the freeboard compared to SiC. The outlet gas temperatures of the receiver with CNTs were higher than those inside the fluidized bed above 0.10 m/s of gas velocity. The temperature increment of gas per irradiance (ΔT/I_DNI) decreased with increasing gas velocity. VACNTs, which are characterized by the coexistence of aggregates and nanotubes in the freeboard, showed a higher value of ΔT/I_DNI than ENCNTs for the same gas velocity. The relative heat absorption temperature (T*) decreased with increasing gas velocity, and dropped below 1.0 at the solid holdup of 0.04, indicating that the freeboard region’s contribution to the receiver’s heat absorption increased. VACNTs and ENCNTs showed maximum thermal efficiencies of 26.7 % and 30.5 % at gas velocities of 0.12 and 0.16 m/s, respectively, which was 33 % higher than that of SiC. Considering the particle properties and particle dynamics, the obtained thermal efficiencies in the present and previous studies were correlated with the Reynolds, Archimedes and Prandtl numbers and the ratios of the specific heat capacities of the particles to the gas.     

Stabilizing effect of the cyclodextrins additive to spray-dried particles of curcumin/polyvinylpyrrolidone on the supersaturated state of curcumin

Although curcumin is considered to have various therapeutic effects, its use as a functional food or supplement is restricted owing to its low water solubility and bioavailability. To increase the solubility of curcumin in water, the use of polyvinylpyrrolidone (PVP) and vinylpyrrolidone-vinyl acetate copolymers with a pyrrolidone skeleton was noted to be promising. In particular, the bi-component formulations of curcumin/PVP prepared through spray drying exhibited an amorphous state in powder X-ray diffraction observations and temporally increased the apparent solubility of curcumin to over 5000 times that of untreated curcumin; nevertheless, after 24 h, the solubility decreased owing to the unstable supersaturated state of curcumin. The addition of α-cyclodextrin (α-CyD) in the bi-component curcumin/PVP formulation helped maintain the supersaturated state of curcumin, whereas the addition of β- and γ-CyD led to the collapse of the supersaturated state. The addition of α-CyD can likely help inhibit the nucleation and crystal growth of curcumin, through the interaction among the solubilized units of curcumin/PVP and α-CyD.     

Particle tracking microrheology of cancer cells in living subjects

Cumulative evidence shows that microenvironmental conditions play a significant role in the regulation of cell functions, and how cells respond to these conditions are of central importance to regenerative medicine and cancer cell response to therapeutics. Here, we develop a new method to examine cell mechanical properties by analyzing the motion of nanoparticles in living in mice, combining particle tracking with intravital microscopy. This method directly examines the mechanical response of breast carcinoma cells and normal breast epithelial cells under intravital microenvironments. Our results show both carcinoma and normal cells display significantly reduced compliance (less deformability) in vivo compared to the same cells cultured in 2D, in both sparse and confluent conditions. While the compliance of the normal cells remains steady over time, the compliance of carcinoma cells decreases further as they form tumor-like architectures. Integrating the cancer cells into spheroids embedded in 3D collagen matrices in part redirected the mechanical response to a state closer to the in vivo setting. Overall, our study demonstrates that the microenvironment is a crucial regulator of cell mechanics and the intravital particle tracking method can provide novel insights into the role of cell mechanics in vivo.     

Designing amorphous formulations of polyphenols with naringin by spray-drying for enhanced solubility and permeability

Naringin (NAR), a major flavanone (FVA) glycoside, is a component of food mainly obtained from grapefruit. We used NAR as a food additive to improve the solubility and permeability of hydrophobic polyphenols used as supplements in the food industry. The spray-dried particles (SDPs) of NAR alone show an amorphous state with a glass transition temperature (T_g) at 93.2 °C. SDPs of hydrophobic polyphenols, such as flavone (FVO), quercetin (QCT), naringenin (NRG), and resveratrol (RVT) were prepared by adding varying amounts of NAR. All SDPs of hydrophobic polyphenols with added NAR were in an amorphous state with a single T_g, but SDPs of hydrophobic polyphenols without added NAR showed diffraction peaks derived from each crystal. The SDPs with NAR could keep an amorphous state after storage at a high humidity condition for one month, except for SDPs of RVT/NAR. SDPs with NAR enhanced the solubility of hydrophobic polyphenols, especially NRG solubility, which was enhanced more than 9 times compared to NRG crystal. The enhanced solubility resulted in the increased membrane permeability of NRG. The antioxidant effect of the hydrophobic NRG was also enhanced by the synergetic effect of NAR. The findings demonstrated that NAR could be used as a food additive to enhance the solubility and membrane permeability of hydrophobic polyphenols.     

Breaking behaviour and interactions in maize and soybean meal while grinding of a hammer mill

The objective of the present study was to investigate whether mixing ratio of maize and soybean meal (SBM) affects the breaking behaviour during hammer-milling in terms of the nutrient properties and in vitro digestibility of fractionated particles. Mixtures of maize and SBM with different proportions (% Maize:SBM; 0:100, 25:75, 50:50, 75:25, 100:0) were hammer milled using a 2-mm screen. The obtained powder was sieved into seven fractions with size ranges from 0.149 to 1.190 mm. Results show that energy consumption of grinding mixtures increased from 3.8 to 48.4 kJ/kg with the maize proportion increasing from zero to 100%. Mixing proportion of maize and SBM showed significant effects on nutrient content of fractionated material. For hammer milled material <595 µm, the in vitro digestibility of crude protein (CP) and organic matter (OM) of fractionated material decreased with increasing particle size. Additionally grinding fractionated particles ≥595 µm over a 1-mm sized screen before in vitro digestion analysis increased the digestibility of OM and CP. Equivalent particle size (EPS) and geometric standard deviation (GSD) of hammer milled maize and SBM and their mixtures correlated better than geometric mean diameter (GMD) to OM and CP in vitro digestibility in a linear regression model. In summary, the mixing ratio of maize and SBM had a significant effect on the breaking behaviour of ingredients and in vitro digestibility of CP and OM of the isolated fractions. Mixing ingredients before grinding is suggested in terms of saving energy consumption. The GSD/EPS of ground material should be considered while studying the effects of particle size distribution on the in vitro digestibility of nutrients.     

Critical perspective on smart thermally self-protective lithium batteries

Thermal safety is one of the most pressing issues facing lithium batteries development, particularly in large-scale battery packs with high power densities. However, traditional external strategies fail to respond immediately to the internal increased heat and pressure. Therefore, it is of great urgency to develop internal control strategies to confer innate thermally self-protective intelligence onto lithium batteries. This paper reviews the research progress of internal intelligent thermal protection methods to improve the thermal safety of lithium batteries. Firstly, through phase separation/transition of electrolytes and thermoregulating separators with phase-change materials or flame retardants, thermal runway could be largely alleviated. However, continuous electrochemical reactions still go on and further heat-generation still exists, thus this kind of strategies can only delay but not eliminate the onset of thermal runaway. Hence, on the other hand, strategies by insulating ionic or current transport to switch off cell reactions have also been developed to avoid heat-generation and eradicate possible thermal runaway. Finally, insights into the future development of smart safer lithium batteries to avoid thermal runaway in terms of consistency, reversibility and adjustability are discussed, offering avenues in the rational design of smart thermally self-protective lithium batteries in the near future.     

用PBⅡ方法在硼膜中注入氮形成BN的结构

用电子束蒸发纯硼,在硅片上沉积不同厚度的硼膜,然后用等离子体基离子注入（ＰＢⅡ）技术在硼膜上主入氮以形成氮化硼（ＢＮ）,用ＸＰＳ分析膜的成分深度分布及化学价态;用傅里叶变换红外（ＦＴＩＲ）透射谱分析膜的结构。氮在膜中呈类似高斯分布,随着注入电压增大,膜的Ｎ／Ｂ比增大且影响氮在膜中的分布,在较高的注入电压时,膜基间产生界面混合,对ＸＰＳＢｌｓ谱进行Ｇａｕｓｓ－ｏｒｅｎｔｚ拟合表明,硼在膜中以ＢＮ及游     

Granulation of ibuprofen/isonicotinamide co-crystals by continuous spray granulator (CTS-SGR)

The importance of granulation is paramount for tablet manufacturing, and is based on the fact that granulated powders are characterized by improved flowability, compressibility, segregation, and dust reduction. The aim of this study was to prepare and characterize continuous granules of high drug content by using a continuous-spray granulator (CTS-SGR). Ibuprofen (IBU), a drug of low-flowability, was selected as the model drug. As IBU has a low melting point and cannot easily granulate on its own, we employed isonicotinamide (INA) as a coformer that would allow us to prepare co-crystal granules containing 60 % IBU. The results of the undertaken differential scanning calorimetry and powder X-ray diffraction revealed that the IBU and the INA in the granules formed co-crystals. The granulation conditions affected the particle size and the yield of the granules; in fact, a low air supply temperature, a low atomizing air rate, and a high solution flow rate ensured a high granulation efficiency. Moreover, continuous granulation increased the yields of the formulations compared to those obtained through a short-run granulation, and high yields were obtained after applying a low atomizing air rate. The circularity of the granules exceeded 90 %, and their flowability improved when compared to that of the IBU bulk. The undertaking of dissolution studies revealed no change in the elution amount of IBU as a result of the co-crystallization. Our study shows that it is possible to produce high-content IBU granules in a direct and continuous manner through the co-crystallization of IBU and the use of a CTS-SGR.     

Screening of sugars and cyclodextrins as carriers in montelukast dry powder inhalers processed by spray freeze drying

The purpose of this study was to develop a site targeting montelukast sodium (MTK) microparticles as a respiratory drug delivery system using the spray freeze drying (SFD) process. A range of sugars and cyclodextrins (CDs) were screened as carrier in order to find compatible excipients for the preparation of dry powder inhalers (DPIs). The physical characteristics of collected powders were studied by scanning electron microscopy (SEM), laser light scattering, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The aerodynamic behavior of the particles was also assessed using twin stage impinge (TSI). In the presence of simple sugars as carriers, highly porous particles in irregular shapes were produced. The use of CDs resulted in the formation of spherical particles with high porosity. Among all carriers that were used during the preparation of powders, raffinose had the best aerodynamic behavior with a fine particle fraction (FPF) of 60 % in sugar groups, while the lowest FPF was related to trehalose as carrier. Powders containing CDs mostly showed proper aerodynamic behavior, especially in formulations containing alfa-cyclodextrin (A-CD), beta-cyclodextrin (β-CD), and highly branched cyclic dextrin (HBCD). Overall, data indicated that the CDs were excellent excipients for use with MTK for respiratory drug delivery.