Search

Black phosphorus (BP) is attracting more and more interest for the biomedical application. The absorption in a wide spectral range and high photothermal conversion efficiency make BP suitable for photothermal therapy. However, BP alone is hard to realize the targeted therapy, which limits the precision and efficiency of the therapy. Magnetic microbubbles (MBs) are favored drug carriers because they can resist the sheer force of blood flow in a magnetic field, which improves the efficiency of MBs adhesion to the vascular wall for targeted ultrasound diagnosis and therapy. This study first optimized the magnetic MBs configurations through controlling the connecting polyethylene glycol (PEG) chain length. The magnetic MBs with PEG2000 have been chosen for targeted BP nanosheets delivery due to the better stability and magnetic responsiveness. The magnetic black phosphorus microbubbles (MBBPM) can realize the targeted tumor theranostics in vitroand in vivo. They could be applied for the targeted ultrasound imaging with an enhanced echogenicity by three times when accumulated at the target site where the magnetic field is applied. As the NIR laser irradiation was applied on the accumulated MBBPM, they dynamited and the temperature increased rapidly. It improved the cell membrane permeability, thus accelerating and enhancing a precision photothermal killing effect to the breast cancer cells, compared to BP alone. more...

To solve the problems of low efficiency and high risk of crack detection in high-rise buildings, the author proposes a building crack image acquisition and processing system based on unmanned aerial vehicle (UAV), expounds the working principle of the system, and analyzes the selection of hardware in the system. The experiment is carried out by combining the acquisition system with the image processing system of the ground station. Based on the characteristics of building surface crack image, an adaptive filtering method is introduced to improve the classic system file checker combination method. The experimental results show that the accuracy of Canny’s method was 96.88%. Canny-based crack target detection method is trained and tested on the crack data set to obtain the classification results and the best detection effect. It is proved that the Canny algorithm based on UAV images can effectively detect cracks on building surface. more...

Electrocatalytic promotion of water splitting is considered an effective way to obtain hydrogen, but it is limited by the expensive nature and scarcity of effective catalysts currently available. Due to their stability, efficient characteristics, and high activity, transition metal phosphides have attracted extensive attention from researchers in electrocatalysis. In this study, the effect of doping with group VIII elements on the hydrogen evolution reaction (HER) activity of CoP (011) was investigated using first-principles calculations based on density functional theory. More active sites were exposed by doping with Rh, Ir, Ni, Pd, and Pt atoms, which significantly improved the catalytic activity of CoP (011) for the HER. It has also been verified by the analysis of the crystal orbital Hamilton population and d-band centers, which indicated the electronic properties resulting in the HER activity improvement. Hydroxylation usually occurs on surfaces lacking coordination in a solution environment, influencing the active sites. Calculations show that adopting suitable transition-element doping can reduce the hydroxyl coverage on the (011) surface of cobalt phosphide and thus improve the HER efficiency. Since surface oxidation is inevitable in the oxygen evolution reaction (OER) process, one case was assumed that all Co atoms in the typical CoP (011) facet were oxidized to form CoOOH, which was studied to explore the mechanism of OER activity. The results indicated that surface oxidation could reduce the OER overpotential, which was the key for CoP to achieve a high-efficiency OER. The theoretical investigations presented that the substitution doping of Fe, Rh, and Ir activated the Co atom adjacent to the dopant atom, which significantly improved performance by adjusting the electronic structure. This theoretical investigation helps to understand the effects of doping and surface oxidation on the electrocatalytic activity of phosphides, and this provides a theoretical perspective basis for the design of transition metal-doped catalysts for overall water splitting. more...

In pancreatic cancer, the special barrier system formed by a large number of stromal cells severely hinders drug penetration in deep tumor tissues, resulting in low treatment efficiency. Cell membrane protein-camouflaged liposomal nanomedicines have cancer cell targeting abilities, whereas near-infrared two-zone (NIR-II) fluorescence imaging can achieve deep tissue penetration due to its long light wavelength (1000-1700 nm). To combine the cell membrane-based biomimetic technology with NIR-II fluorescence imaging, we constructed a biomimetic nanomedicine (BLIPO-I/D) by camouflaging indocyanine green-doxorubicin (ICG-DOX) liposomes with SW1990 pancreatic cancer cell membrane. The nanomedicine exhibited light-controlled DOX release and high pancreatic cancer treatment efficiency in vitroand in vivo. BLIPO-I/D showed the ability of targeted delivery of a large number of liposomes to pancreatic tumor tissues through homologous targeting of SW1990 cell membranes, which increased the NIR-II fluorescence imaging intensity. Irradiation of the liposomes taken up by pancreatic tumor tissues with near-infrared light (808 nm) triggered the rapid release of DOX from the liposomes, induced the photothermal and photodynamic effects of ICG, which exerted anti-tumor effects. Therefore, the fabricated biomimetic liposomal nanomedicine BLIPO-I/D is expected to achieve precise theranostics of pancreatic cancer. more...