ABSTRACT
Surface tension and interfacial tension are crucial to the study of nanomaterials. Herein, we report a solubility method using magnesium oxide nanoparticles of different radii (1.8-105.0 nm, MgO NPs) dissolved in pure water as a targeted model; the surface tension and interfacial tension (and their temperature coefficients) were determined by measuring electrical conductivity and combined with the principle of the electrochemical equilibrium method, and the problem of particle size dependence is discussed. Encouragingly, this method can also be used to determine the ionic (atomic or molecular) radius and Tolman length of nanomaterials. This research results disclose that surface/interfacial tension and their temperature coefficients have a significant relationship with particle size. Surface/interfacial tension decreases rapidly with a radius <10 nm (while the temperature coefficients are opposite), while for a radius >10 nm, the effect is minimal. Especially, it is proven that the value of Tolman length is positive, the effect of particle size on Tolman length is consistent with the surface/interfacial tension, and the Tolman length of the bulk does not change much in the temperature range. This work initiates a new era for reliable determination of surface/interfacial tension, their temperature coefficients, ionic radius, and Tolman length of nanomaterials and provides an important theoretical basis for the development and application of various nanomaterials.
ABSTRACT
3D printing technology is an increasing approach consisting of material manufacturing through the selective incremental delamination of materials to form a 3D structure to produce products. This technology has different advantages, including low cost, short time, diversification, and high precision. Widely adopted additive manufacturing technologies enable the creation of diagnostic tools and expand treatment options. Coupled with its rapid deployment, 3D printing is endowed with high customizability that enables users to build prototypes in shorts amounts of time which translates into faster adoption in the medical field. This review mainly summarizes the application of 3D printing technology in the diagnosis and treatment of cancer, including the challenges and the prospects combined with other technologies applied to the medical field.
Subject(s)
Neoplasms , Printing, Three-Dimensional , Humans , Neoplasms/diagnosis , Neoplasms/therapyABSTRACT
Oxygen Vacancy (OVs) and carbon doping of the photocatalyst body will significantly enhance the photocatalytic efficiency. However, synchronous regulation of these two aspects is challenging. In this paper, a novel C@TiO2-x photocatalyst was designed by coupling the surface defect and doping engineering of titania, which can effectively remove rhodamine B (RhB) and has a relatively high performance with wide pH range, high photocatalytic activity and good stability. Within 90 minutes, the photocatalytic degradation rate of RhB by C@TiO2-x (94.1 % at 20â mg/L) is 28 times higher than that of pure TiO2 . Free radical trapping experiments and electron spin resonance techniques reveal that superoxide radicals (â O2- ) and photogenerated holes (h+ ) play key roles in the photocatalytic degradation of RhB. This study demonstrates the possibility of regulating photocatalysts to degrade pollutants in wastewater based on an integrated strategy.
ABSTRACT
Correction for 'Critical size effect for the surface heat capacities of nano-CdS: theoretical and experimental studies' by Shengjiang Zhang et al., Phys. Chem. Chem. Phys., 2022, 24, 6193-6207, https://doi.org/10.1039/D1CP04619E.
ABSTRACT
The unique physical and chemical properties of nanomaterials are closely related to their surface thermodynamic functions, which mainly depend on their sizes. In this study, the thermodynamic properties of nano-cadmium sulphide (nano-CdS) were investigated by solubility technology. The nano-CdS powders with different particle sizes were prepared via a traditional solvothermal method, and the electrical conductivities of nano-CdS aqueous solutions at different temperatures were measured. The standard dissolution equilibrium constants of nano-CdS at different temperatures were calculated using the theory of dissolution thermodynamics. The standard molar dissolution thermodynamic functions, the molar surface thermodynamic functions and the specific surface thermodynamic functions of nano-CdS with different particle sizes were calculated by combining the thermodynamic functions of bulk-CdS, the principle of the thermodynamic cycle and the principle of electrochemical equilibrium. The experimental results show that the critical size values for the molar surface heat capacity and the specific surface heat capacity for approximately spherical nanoparticles are 9.3 nm and 8.7 nm, respectively. Within an acceptable range of error, the thermodynamic functions have linear and curved relationships with particle sizes and temperatures. Based on these results, it is disclosed that the critical size effect on surface heat capacities of nano-CdS is valuable to understand the energy storage processes of nanomaterials.
ABSTRACT
Novel magnetic Fe(3)O(4)/chitosan (CS) microspheres were prepared using magnetic Fe(3)O(4) nanoparticles and the natural macromolecule chitosan. Then, using an easy and effective hemoglobin (Hb) immobilization method, an innovative biosensor with a Fe(3)O(4)/CS-Hb-Fe(3)O(4)/CS "sandwich" configuration was constructed. This biosensor had a fast (less than 10 s) response to H(2)O(2) and excellent linear relationships were obtained in the concentration range of 5.0 × 10(-5) to 1.8 × 10(-3) M and 1.8 × 10(-3) to 6.8 × 10(-3) M with a detection limit of 4.0 × 10(-6) M (s/n = 3) under the optimum conditions. The apparent Michaelis-Menten constant K(m) was 0.29 mM and it showed the excellent biological activity of the fixed Hb. Moreover, the biosensor had long-time stability and good reproducibility. The method was used to determine H(2)O(2) concentration in real samples.
