Good Dispersion Stability Research Articles

Research on the preparation of cellulose nanocrystals from balsa wood using microwave-assisted synergistic deep eutectic solvent and H2O2 extraction

Utilizing natural balsa wood as the raw material, cellulose was prepared using microwave-assisted chlorocholine chloride/lactic acid deep eutectic solvents (DES) in synergy with H2O2, followed by further preparation of cellulose nanocrystals (CNCs) via ultrasound treatment. Initially, the optimal process for balsa wood cellulose preparation was explored through single-factor and response surface experiments involving microwave-assisted DES in synergy with H2O2 treatment. Subsequently, cellulose nanocrystals were prepared using ultrasound, and the resulting materials were characterized and analyzed for their chemical composition, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), nanoparticle size distribution, transmission electron microscopy (TEM) analysis, and thermogravimetric-differential scanning calorimetry (TG-DSC). The results indicate that the yield of cellulose after microwave-assisted DES in synergy with H2O2 treatment can reach 42.96%. Furthermore, the cellulose nanocrystals obtained after ultrasound treatment exhibit a particle size ranging from 10 to 20 nm, with an average length of 515.9 nm, a crystallinity of 86.72%, and demonstrate good dispersion and thermal stability.

Preparation of Modified Polycarboxylate by Pyrrolidone for Using as a Dispersant in Cobalt Blue Nano-Pigment Slurry.

In this paper, N-vinylpyrrolidone was copolymerized with acrylic acid and itaconic acid by free radical polymerization, and a series of polyacrylic acid-co-itaconic acid-co-N-vinylpyrrolidone (PAIN) dispersants with different pyrrolidone ligand contents were synthesized and characterized. Then, the cobalt blue nano-pigment slurry (20 wt%) was prepared through a water-based grinding method, and the optimum grinding technology was explored and determined as follows: PAIN2 as a dispersant, a dispersant dosage of 10 wt%, and a grinding time of 480 min. According to this optimum grinding technology, the prepared pigment slurry had a significantly decreased agglomeration, the D90 of which was 82 nm, and separately increased to 130 nm and 150 nm after heat storage for 3 and 7 days, exhibiting excellent heat storage stability. Additionally, its TSI value was also the lowest (1.9%), indicating good dispersion stability. The QCM and adorption capacity measuring results showed PAIN2 had a larger adsorption capacity, and the formed adsorption layer had a higher rigidity and was not easy to fall off. This was caused by both the interaction of carboxyl groups and the pyrrolidone ligand (strong coordination interaction) in PAIN2 with cobalt blue. The XPS and FT-IR measurements further proved the above-mentioned adsorption mechanism.

Magnetic solid-phase extraction technique based on Fe3O4@coPPy-PTH nanocomposite for extraction of cobalt, chromium, and nickel prior to determination by microsample injection system-flame atomic absorption spectrometry in alcoholic and nonalcoholic beverages.

A novel Fe3O4@coPPy-PTH nanocomposite-based sorbent was prepared via in situ oxidative polymerization using Fe3O4 nanoparticles with spherical and flower-like morphologies of thiophene and pyrrole as the feedstocks. The synthesized nanocomposite displayed sensitive extraction and determination of metal ions Co(II), Cr(III), and Ni(II) without a chelating agent, followed by microsample injection system-flame atomic absorption spectrometry. Advanced spectroscopic and imaging techniques including scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy were used to characterize the composition and morphology of the Fe3O4@coPPy-PTH nanocomposite. SEM observations showed that the size of the Fe3O4 nanoparticles changed from 30 nm to 120 nm in diameter after copolymer (PPy-PTH) coating. The Fe3O4@coPPy-PTH nanocomposite has good dispersion properties and stability in strong acid solutions. For effective extraction of the studied analytes, the influence of sample pH, volume of sample solution and eluent, amount of adsorbent, and interference of coexisting metal ions were optimized. Under the optimum conditions, preconcentration factors were obtained as 25 for all analytes. The calibration curves were linear in the range of 0.0-10.0 μg L-1 with coefficients of determination (R2) greater than 0.9957 for all three analytes. Limits of detection (S/N = 3) were calculated in the range of 0.17-0.23 μg L-1. Precision values, expressed as relative standard deviations, were lower than 3.0%, and relative recoveries were obtained in the range of 88.6%-103.6%. The proposed method (Fe3O4@coPPy-PTH/MSPE/MIS-FAAS) was successfully applied to extract and determine the studied metal ions in beer, wine, and nonalcoholic beverage samples.

Carrier-free nano-prodrugs for minimally invasive cancer therapy.

An anticancer nanodrug with few side effects that does not require the use of a nanocarrier, polyethylene glycol, or other additives has been developed. We have fabricated nano-prodrugs (NPDs) composed only of homodimeric prodrugs of the anticancer agent SN-38, which contains a disulfide bond. The prodrugs are stable against hydrolysis but selectively release SN-38 when the disulfide bond is cleaved by glutathione, which is present in high concentrations in cancer cells. The best-performing NPDs showed good dispersion stability in nanoparticle form, and animal experiments revealed that they possess much higher antitumor activity than irinotecan, a clinically applied prodrug of SN-38. This performance was achieved by improving tumor accumulation due to the size effect and targeted drug release mechanism. The present study provides an insight into the development of non-invasive NPDs with high pharmacological activity, and also offers new possibilities for designing prodrug molecules that can release drugs in response to various kinds of triggers.

Dynamic Directional Ultrasonically In Situ-Generated N,S-Codoped Carbon Dots in Poly(ethylene glycol) for Improved Tribological Performance.

The dispersion stability of nanomaterials in lubricants significantly influences tribological performance, yet their addition as lubricant additives often presents challenges in secondary dispersion. Here, we present a straightforward method for in situ preparation of N,S-codoped CDs (N,S-CDs)-based lubricants using heterocyclic aromatic hydrocarbons containing N/S elements in poly(ethylene glycol) (PEG) base oil by a directional ultrasound strategy. Two types of N,S-CDs were successfully prepared via the directional ultrasound treatment of PEG with benzothiazole (BTA) and benzothiadiazole (BTH) separately. The resultant N,S-CDs have a uniform distribution of N and S elements and maintain good colloidal dispersion stability in PEG even after 9 months of storage. The N,S-CDs can enter the surface gap of the friction pairs and then induce a tribochemical reaction. Benefiting from the synergistic effect of N and S activating elements, a robust and stable protective film consisting of iron sulfides, iron oxides, carbon nitrides, and amorphous carbonaceous compounds is formed, thus endowing N,S-CDs-based lubricants with improved antiwear and friction-reducing performance. Compared with pure PEG, the coefficient of friction (COF) of the N,S-CDs(BTH)-based lubricant decreased to 0.108 from 0.292, accompanied by a 91.2% reduction in wear volume, and the maximum load carrying capacity increased to 450 from 150 N.

Effects of Fly Ash and Graphene Oxide in Cement Mortar Considering the Local Recycled Material Context

Construction materials are at the forefront of global economic development as they provide the foundation for the infrastructure of other industries, with cementitious materials being predominantly used in construction projects. To promote sustainable development, alternative materials are added to cement mortar to increase durability and reduce emissions. In this regard, graphene oxide (GO) and fly ash (FA) are two alternative materials commonly used in cement mortar, which are readily available or are just the waste from other local material production. With different ratios, the amount of GO and FA can affect the properties of cement mortar positively or negatively. This study aims to determine the effects of GO and FA on cement mortar mixtures under material conditions. Research results show that 10 wt% FA and 0.036 wt% GO will give cement mortar the best physical and mechanical properties while ensuring other necessary properties, such as workability. When increasing FA to 30 wt% or GO to 0.05 wt%, the strength of the mortar mixture tends to decrease. Another issue is that the specific surface area of graphene is very high, which poses a significant challenge when uniform dispersion in the cement paste mixture is required. Polycarboxylate combined with a specific mixing sequence has demonstrated good dispersibility and high stability. Through this research, it is demonstrated that the addition of GO and FA has the potential for sustainable development of the construction industry by considering the contexts of the local recycled cementitious replacement materials.

Mesoscale Acid-Base Complexes Display Size-Associated Photophysical Property and Photochemical Activity.

The properties of single molecules and molecular aggregates can differ dramatically, leading to a long-standing interest in mesoscale aggregation processes. Herein, a series of acid-base molecular complexes is developed by using a tetraphenylethylene-backboned fluorophore, and investigated the photophysical properties and photochemical activities at different aggregation length scales. This fluorophore, with two basic diethylamine groups and two acidic tetrazole groups, exhibits sparse solubility due to multivalent interactions that cause infinite aggregation. The addition of a third acid leads to the formation of fluorophore/acid complexes with good dispersibility and colloidal stability. This assembly process can be controlled by the use of different acids and their stoichiometry, resulting in aggregates ranging in size from a few to hundreds of nanometers. A crystalline structure is obtained to illustrate the complex properties of the acid-base network. Unlike the single molecule, these complexes show a trend of size-related properties for photoluminescence efficiency and photochemical activity. As the amount of acid added increases, the size of the complexes decreases, the aggregation effect of the complexes on fluorescence emission increases, and the rates of the oxidative photocyclization and photodecomposition slow down. This work may help to understand size-controlled molecular materials at the mesoscale for functional design.

Study on the Permeability Enhancement of Propped Fractures under the Action of a Coal Fine Plugging Removal Agent.

The retention of coal fines in propped fractures impedes the efficient flow of gas and water, leading to a substantial decrease in coal seam permeability and gas production efficiency. In this article, a coal fine plugging removal agent with good dispersion stability and powerful powder-carrying capacity was developed to study the coal fine plugging removal and permeability enhancement in the propped fracture. The results show that 0.8% SDS + 0.4% NaCl + 0.8% BS-12 was the most effective coal fine plugging removal agent compounding system. Increasing the injection rate of the plugging removal agent and performing recycles of intermittent unblocking when it was used as a plugging agent will effectively enhance the gas-liquid two-phase effective permeability of propped fractures and improve the release of retained coal fines. After three recycles of intermittent unblocking, the coal fine discharging rate can be increased to more than 90%, resulting in a 3.88 times increase of the gas-liquid two-phase permeability compared to that with the single unblocking cycle. This method has important practical significance and theoretical value for solving the problem of coal fine plugging in fractures and ensuring the stable and efficient discharge of coalbed gas-water-coal fines.

Experimental study on preparation and heat transfer efficiency of ethylene glycol/water-based hybrid nanofluids enhanced by graphene oxide/MXene nanoparticles

In this study, the preparation and heat transfer efficiencies of ethylene glycol (EG)/water-based (50:50) hybrid nanofluids were enhanced using graphene oxide (GO)/MXene (1:1) nanoparticles. The stability of the nanofluids was analyzed, and the thermal conductivity and viscosity were tested at 20–60 °C. A correlation equation for the thermal conductivity ratio of the nanofluids was proposed. The heat transfer efficiency of the nanofluids was evaluated using the performance enhancement ratio (PER) and Mouromtseff number (Mo). The prepared EG/water-based GO/MXene nanofluids exhibited good chemical and dispersion stability. The thermal conductivity and viscosity of the nanofluids gradually increased with the GO/MXene dosage. The nanofluid containing 0.3 wt% GO/MXene nanoparticles exhibited the largest thermal conductivity increment of 33.49 % at 60 °C compared with EG/water and maintained the low viscosity. The proposed prediction equation based on the temperature and mass dosage was highly accurate. The PER and Mo demonstrated the suitability of the GO/MXene nanofluids for heat transfer applications.

Green Synthesis of CQDs via the Trunks of Bauhinia purpurea as Fluorescence Probes for Rapid and Accurate Detection of Quinoline Yellow.

Carbon quantum dots (CQDs) were greenly synthesized via a single-step hydrothermal method, using the trunks of Bauhinia purpurea as the carbon source. They exhibited good dispersibility, water solubility, high sensitivity, and great stability with a spherical form and a particle size of 2.68 ± 0.32 nm. By utilizing the inner filter effect and dynamic quenching effect, the fluorescence quenching of CQDs can be induced to detect quinoline yellow. Detailed experimental results showed that the change rate of fluorescence intensity of CQDshadagood linearrelationshipwith varying concentrations of quinoline yellow (2-128 µmol/L). It can be clearly observed that the fluorescence quenching occurred within 1 min, its correlation coefficient (R2) is 0.9912, and the detection limit (DL) is 1.7884 μmol/L, substantially lower than the maximum concentration stipulated by the national standard of 209.5 µmol/L. Furthermore, quinoline yellow had been successfully detected in real beverage samples using CQDs, with the recovery rates of 90.6%-110.4% and the relative standard deviation (RSD) ≤ 6.3% and it also showed great anti-interference and selectivity. These findings indicate that the detected quinoline yellow of CQDs possess substantial promise for a wide range of applications within the detected artificial food colors field.

Stability, Thermophysical, Optical and Photothermal Properties of ZnO Nanofluids with Added Anionic/Cationic Mixed Surfactants

Metal oxide nanofluid is a new type of heat transfer medium with good thermal performance, which can be used to improve the heat collection and photothermal conversion performance of the collector. The development of new nanofluids with excellent stability, thermophysical and photothermal properties is very important for solar thermal utilization. In this paper, the ZnO nanofluids with SDS/CTAB mixed surfactants were prepared by two-step method. Their stability, thermophysical, optical and photothermal properties were studied based on experimental data. Then, the optimum concentration and preparation conditions of the proposed ZnO nanofluids adding SDS/CTAB with good photothermal performance were obtained. The results showed that the ZnO nanofluids with the addition of SDS/CTAB hybrid surfactant has good dispersion stability and its thermal conductivity can reach 0.772 W/(m·K). The transmittance was as low as 19.0.10% and the extinction coefficient was as high as 7.25 cm−1. In addition, the addition of the SDS/CTAB hybrid surfactant caused the ZnO nanofluids to exhibit better photothermal conversion efficiency up to 87%, which was superior to that of the control group with the addition of other surfactants. Therefore, ZnO nanofluids with the addition of SDS/CTAB have great potential as DASC working fluids.

Tuning Surface, Phase, and Magnetization of Superparamagnetic Magnetite by Ionic Liquids: Single-Step Microwave-Assisted Synthesis.

Achieving colloidal and chemical stability in ferrofluids by surface modification requires multiple steps, including purification, ex situ modification steps, and operation at high temperatures. In this study, a single-step microwave-assisted methodology is developed for iron oxide nanoparticle (IONP) synthesis utilizing a series of imidazolium-based ionic liquids (ILs) with chloride, bis(trifluoromethylsulfonyl)imide, and pyrrolide anions as the reaction media, thus eliminating the use of volatile organics while enabling rapid synthesis at 80 °C as well as in situ surface functionalization. The characterized surface functionality, hydrodynamic particle size, magnetization, and colloidal stability of the IONPs demonstrate a strong dependence on the IL structure, ion coordination strength, reactivity, and hydrophilicity. The IONPs present primarily a magnetite (Fe3O4) phase with superparamagnetism with the highest saturation magnetization at 81 and 73 emu/g at 10 and 300 K, respectively. Depending on the IL coating, magnetization and exchange anisotropy decrease by 20 and 2-3 emu/g (at 35 wt % IL), respectively, but still represent the highest magnetization achieved for coated IONPs by a coprecipitation method. Further, the surface-functionalized superparamagnetic magnetite nanoparticles show good dispersibility and colloidal stability in water and dimethyl sulfoxide at 0.1 mg/mL concentration over the examined 3 month period. This study reports on the intermolecular and chemical interactions between the particle surface and the ILs under synthetic conditions as they relate to the magnetic and thermal properties of the resulting IONPs that are well suited for a variety of applications, including separation and catalysis.

A kidney-targeted chitosan-melanin nanoplatform for alleviating diabetic nephropathy through modulation of blood glucose and oxidative stress

Diabetic nephropathy (DN) is a serious complication in patients with diabetes, whose expansion process is closely related to oxidative stress caused by hyperglycemia. Herein, we report a chitosan-targeted dagliflozin-loaded melanin nanoparticle (CSMDNPs) that can selectively accumulate in injured kidneys, reduce blood glucose, and alleviate the oxidative stress-induced damage. CSMDNPs possess good dispersion and physiological stability, responsive release at acidic pH, and strong scavenging activities for various reactive oxygen and reactive nitrogen radicals. Moreover, in vitro experiments confirm that CSMDNPs have good biocompatibility, enable targeted uptake in NRK-52E renal tubular cells, and also well alleviate high glucose-induced oxidative stress. In the STZ-induced DN model, CSMDNPs exhibit high targeting distribution and retention in the damaged kidneys of DN mice according to photoacoustic imaging. At the end of CSMDNPs treatment, DN mice show a decrease in fasting blood glucose and a return to near-normal urine and blood indices. H&E, PAS, and masson pathological staining also indicates that CSMDNPs significantly inhibit the expansion of renal interstitium, glycogen, and collagen deposition, showing excellent therapeutic effects. In addition, melanin acts as both drug carrier and antioxidant without exogenous carrier introduction, exhibiting better biosafety and translational prospects.

Experimental Study on Dispersion Stability and Polishing Performance of Polishing Solution Based on Micro-Abrasive Water Jet Polishing

In micro-abrasive water jet polishing (MAWJP) technology, where abrasive particles serve as polishing tools, particles tend to form large clusters, leading to increased nozzle wear and diminished material polishing quality. Achieving a polishing solution with good dispersion stability is crucial for enhancing polishing accuracy and minimizing nozzle wear. Therefore, this study employed three dispersants with distinct dispersion mechanisms to examine the impact of each dispersant’s concentration on the dispersion stability of the polishing solution across various abrasive concentrations. Through experimentation, the optimal dispersant type and concentration ratio of abrasive to dispersant were determined, and the effect of the selected dispersant on jet polishing performance was validated. The results of the dispersion stability experiment indicated that, in comparison to Na(PO3)6 and polyethylene glycol (PEG), the polishing solution containing 1.0–2.0 wt% phosphoric ester compounds exhibited a more stable dispersion effect (zeta potential < −50 mV) and superior dispersibility, characterized by a smaller average particle size. Furthermore, K9 optical glass was subjected to fixed-point and local polishing using phosphoric ester compounds as the dispersant. The fixed-point polishing experiment revealed that, at a dispersant concentration of 1.0 wt% and an abrasive concentration of 20 wt%, a smooth and symmetrical material removal profile could be achieved. In the local polishing experiment, the reduction rate of the root mean square of the surface roughness (RMS) increased from 54.33% to 82.24%, and the reduction rate of peak-to-valley height difference in surface (PV) increased from 38.84% to 68.97%. In conclusion, the incorporation of a dispersant proves effective in enhancing the dispersion stability of the polishing solution and dispersibility of the abrasive particles, thereby improving the surface quality of the materials in MAWJP.

Experiment on Heat Exchanger Using Innovative Coils and Phase Change Material/MXene Nanofluids

The utilization of innovative coiled wire turbulators along with phase change material (PCM; improving heat capacity) or MXene (having good dispersion stability) dispersed nanofluid in tubular heat exchangers may boost performance; however, it has not been explored yet. In the current analysis, experimental research is done on various mono-nanofluids and hybrid nanofluids flowing in a double-pipe heat exchanger with tapered, coiled wire turbulators to examine the hydrothermal aspects. Four coiled wire turbulators (conventional helical, conversing tapered, diverging tapered, and converging–diverging tapered) and four nanofluids (Al2O3/water, PCM/water, Al2O3+PCM/water and MXene/water) are utilized in the heat exchanger with all possible combinations. The effects of fluid types, turbulator types, total nanoparticle volumetric fraction, and nanofluid volume flow rate are investigated. Two thermal parameters (heat transport coefficient and Nusselt number), two hydraulic parameters (drop of pressure and friction coefficient), and two hydrothermal parameters (ratio of heat transport coefficient and drop of pressure, and generation of entropy) are considered objective functions. The study reveals that the diverging tapered, coiled wire yields significantly higher performance as compared to the conventional helical coiled wire as an insert. MXene/water has higher thermal performance; however, PCM-dispersed hybrid nanofluid yields better hydrothermal performance than other studied fluids.

Pickering emulsion approach: A novel strategy to fabricate waterborne polyurethane with enhanced abradability and water-resistance comparable to that of solvent-based coating

The urgent requirement of replacement for solvent polyurethane (PU) makes waterborne polyurethane (WPU) coating more attractive and popular in many industrial areas. However, the simultaneous realization of good dispersion stability and high performance of the cured films especially water resistance remains challenging. Herein, we propose a novel and facile Pickering emulsion approach to fabricate WPU with enhanced abradability and water-resistance comparable to that of solvent-based PU coating. In this approach, the hydrophobic polyurethane synthesized by poly-addition reaction in ethyl acetate is directly dispersed into water with SiO2 nanoparticles as Pickering stabilizer followed by subsequent evaporation of the remaining solvent to obtain Pickering waterborne polyurethane dispersion (PWPU dispersion). The ability of SiO2 to stabilize emulsion can be modulated by hydrophobic modification with propyltriethoxysilane (PTS). SiO2 nanoparticles with an optimal PTS-grafting rate of 2.8 wt% enables the PWPU dispersion with excellent long-term, chemical, thermal, and freeze-thaw stability. The highly-transparent composite films with honeycomb structures are readily formed by casting PWPU dispersion at room temperature. The thermal and mechanical properties of PWPU films are comparable to or superior to solvent-borne polyurethane (SPU) and self-emulsifying waterborne polyurethane (SWPU) films. Moreover, the water absorption of the PWPU-5 film is approximately 20 times lower than that of SWPU, demonstrating the excellent water-resistance. We further validated the coating performance of PWPU for leather finishing. The hydrophobicity, abrasion resistance and water vapor permeability of PWPU-coated leather are superior to those of SPU and SWPU-coated leather.

A dual-emission ratiometric luminescence probe based on Zr-MOFs for the efficient detection of Cu2+ in aqueous solutions

A novel dual-emission ratio luminescent probe (Eu(DPA)3@UIO-66-NH2) for the detection of Cu[Formula: see text] in an aqueous solution was successfully prepared by linking the Zr-MOFs material UIO-66-NH2 with the lanthanide complex Na3[Eu(DPA)3] through the interaction between functional groups. The synthesized Eu(DPA)3@UIO-66-NH2 inherits the advantages of MOFs and lanthanide complexes, and it not only has excellent luminescence performance but also shows good dispersion and structural stability in aqueous solution. The characteristics of dual-emission light can achieve specific ratiometric luminescence detection of Cu[Formula: see text]. In addition, the probe exhibited high sensitivity for the detection of Cu[Formula: see text]with a detection limit as low as 0.89 [Formula: see text]M. It can provide an efficient and stable platform for the convenient and rapid detection of Cu[Formula: see text] in aqueous solutions and has the potential for development applications.

Self-templated fabrication of P-doped CoMoO4-Co3O4 hollow nanocages for the efficient oxygen evolution reaction.

Finding reservoir-rich and efficient electrocatalysts for the alkaline oxygen evolution reaction (OER) is crucial for further sustainable energy development. Despite the advantages of high earth abundance, easy availability, and tunable composition, transition-metal oxides are typically considered poor electrocatalysts for the OER. In this study, a composite P-doped CoMoO4-Co3O4 hollow nanocage is deliberately synthesized through a cation-exchange, pyrolysis, and phosphorization approach using an innovative self-template strategy with ZIF-67 as the sacrificial template. Hollow nanocages provide large surface areas and abundant active sites, enhancing electron transfer. Hybridization with other components increases the number of electrochemically reactive sites and optimizes the advantages of different element components. As a result, the P-CoMoO4-Co3O4 hollow nanocage catalyst demonstrates high OER performance, with an overpotential of 279 mV at a current density of 10 mA cm-2. Additionally, P-CoMoO4-Co3O4 catalysts exhibit good dispersibility and excellent long-term stability. Experimental findings and density functional theory (DFT) calculations indicate that the phosphorus-doping effect in various aspects contributes significantly to the superior catalytic activity of P-CoMoO4-Co3O4. This work provides a valuable method for designing cost-effective P doped Co-based bimetal oxide catalysts with outstanding OER performance for industrial applications.

Synergistic anti-tumor effect of dual drug co-assembled nanoparticles based on ursolic acid and sorafenib

Both ursolic acid (UA) and sorafenib (Sora) have been generally utilized in cancer treatment, and the combination of the two has also shown a good anti-tumor effect. However, single-agent therapy for Hepatocellular carcinoma (HCC) has the disadvantages of multi-drug resistance, poor water solubility and low bioavailability, and the application of traditional nanocarrier materials is limited due to their low drug loading and low carrier-related toxicity. Therefore, we prepared US NPs with different proportions of UA and Sora by solvent exchange method for achieving synergistic HCC therapy. US NPs had suitable particle size, good dispersibility and storage stability, which synergistically inhibited the proliferation of HepG2 cells, SMMC7721 cells and H22 cells. In addition, we also proved that US NPs were able to suppress the migration of HepG2 cells and SMMC7721 cells and reduce the adhesion ability and colony formation ability of these cells. According to the results, US NPs could degrade the membrane potential of mitochondrial, participate in cell apoptosis, and synergistically induce autophagy. Collectively, the carrier-free US NPs provide new strategies for HCC treatment and new ideas for the development of novel nano-drug delivery systems containing UA and Sora.

Improvement of dispersion stability and polishing performance of chemical mechanical polishing slurry for cemented carbide inserts

Aiming at defects such as small pits and scratches on the surface caused by the aggregation of alumina particles during the chemical mechanical polishing (CMP) process of the cemented carbide inserts, the effect of the dispersant types, pH and dispersant concentration on the dispersion stability of the alumina suspension is investigated. It is found that sodium dodecyl sulfate (SDS) is the best dispersant of the six different dispersants, and the suspension has good dispersion stability when the pH value is 11 and the SDS concentration is 3 wt%. Furthermore, based on the DLVO theory, SDS is verified to improve suspension stability at the micro-scale. Finally, the insert CMP experiments are carried out using the polishing slurry with SDS and without dispersant. CMP experiments show that using the polishing slurry with SDS to polish the insert can achieve a better material removal rate (MRR) and lower surface roughness.