Integration of disease diagnosis and therapy in vivo by nanotechnology is a challenge in the design of multifunctional nanocarriers. Herein, we report an intelligent and degradable nanoreactor, an ...assembly of the 4-mercaptobenzonitrile-decorated silver nanoparticles (AgNPs@MBN) and the glucose oxidase (GOx)-loaded metal-organic-framework (ZIF-8@GOx), which can be activated by tumor microenvironment to start the catalytic cascade-enhanced chemo-starvation synergistic therapy and simultaneous self-sense of cellular glucose level. Under the mild acidic microenvironment of tumor, the nanoreactor will collapse to release GOx that triggers a catalytic cascade reaction in vivo, depleting glucose, etching AgNPs@MBN, and producing toxic H2O2, Ag+, and Zn2+ ions, all of which work together to inhibit tumor growth. The AgNPs@MBN as SERS nanoprobe reads out glucose concentration noninvasively in tumor to achieve instant feedback of therapeutic progression. This work proposes a promising example of using enzyme-encapsulated biomineralized MOFs as an effective anticarcinogen for clinical applications.
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•This nanoreactor integrates in vivo sensing and synergistic therapy capabilities•The ZIF-8 nanocarrier protects GOx from deactivation and immune clearance•The nanoreactor is biodegradable, avoiding the side effects on tumor-bearing mice•Instant non-invasive glucose feedback capability realized by in vivo SERS
Biomaterials; Biomedical Engineering; Nanostructure
Energy saving is one of the main technique routes for net zero carbon emissions. Air compressor systems take up a large part of energy consumption in the industrial field. A pre-cooling air ...compressor system was proposed for energy saving by cooling the air before it flows in a compressor. The energy efficiency of the proposed system was analyzed. As additional energy consumption is required for air cooling, the feasibility of the pre-cooling method for energy saving was analyzed. As the efficiency of the pre-cooling air compressor system is mainly influenced by the environment temperature and humidity, applicability of the system in different regions and at different seasons was discussed. A pilot project was performed to verify the technical feasibility and economics of the proposed system. When the precooling temperature of the pilot system was set to 2 °C, the annual pneumatic-electrical ratio of the system can be increased by approximately 2% in several regions of China. This paper shows the pre-cooling air compressor system is feasible for energy saving.
Cough is a protective respiratory reflex used to clear respiratory airway mucus. For patients with cough weakness, such as chronic obstructive pulmonary disease, neuromuscular weakness disease and ...other respiratory diseases, assisted coughing techniques are essential to help them clear mucus. In this study, the Eulerian wall film model was applied to simulate the coughing clearance process through a computational fluid dynamics methodology. Airway generation 0 to generation 2 based on realistic geometry is considered in this study. To quantify cough effectiveness, cough efficiency was calculated. Moreover, simulations of four different coughing techniques applied for chronic obstructive pulmonary disease and neuromuscular weakness disease were conducted. The influences of mucus film thickness and mucus viscosity on cough efficiency were analyzed. From the simulation results, we found that with increasing mucus film thickness and decreasing mucus viscosity, cough efficiency improved accordingly. Assisted coughing technologies have little influence on the mucus clearance of chronic obstructive pulmonary disease models. Finally, it was observed that the cough efficiency of the mechanical insufflation-exsufflation technique (MIE) is more than 40 times the value of an unassisted coughing technique, which indicates that the MIE technology has a great effect on airway mucus clearance for neuromuscular weakness disease models.
Water-spray-cooled quasi-isothermal compressed air energy storage aims to avoid heat energy losses from advanced adiabatic compressed-air energy storage (AA-CAES). The compression efficiency ...increases with injection water spray. However, the energy-generated water spray cannot be ignored. As the air pressure increases, the work done by the piston and the work converted into heat rise gradually in the compression process. Accordingly, the flow rate of the water needed for heat transfer is not a constant with respect to time. To match the rising compression heat, a time sequence of water-spray flow rate is constructed, and the algorithm is designed. Real-time water-spray flow rate is calculated according to the difference between the compression power and heat-transfer power. Compared with the uniform flow rate of water spray, energy consumption from the improved flow rate is reduced.
Although carbon nanozymes have attracted great interest due to their good biocompatibility, low cost, and high stability, designing high-active carbon nanozymes still faces great challenges. Herein, ...ultrathin nitrogen-doped carbon nanosheets with rich defects (d-NC) were prepared through a high-temperature annealing process, using potassium chloride and ammonium chloride as templates. Owing to the large specific surface area, rich defects and the high exposure of active sites, the proposed d-NC nanozymes exhibited excellent peroxidase-like activity. The d-NC nanozymes possess maximal reaction velocity and their specific activity is 9.4-fold higher than that of nitrogen-doped carbon nanozymes, indicating that the induced defects can boost the catalytic performance. Benefited from the good peroxidase-like activities of d-NC nanozymes, the colorimetric sensing platforms were constructed for the detection of urease activity and fluoride ion, exhibiting satisfactory stability and selectivity. This study not only offers a way to synthesize carbon nanozymes with improved enzyme-like activities but also broadens their applications in colorimetric biosensing.
Display omitted The colorimetric sensing platform based on defect-rich and ultrathin nanozymes was constructed for the detection of urease activity and fluoride ion.
Air is usually compressed adiabatically in the compressor. As the operating speed of compressors can be several thousand rpm, heat generated during compression cannot be sufficiently transmitted to ...the environment in such a short time. It is for this reason that compressor efficiency is limited. Isothermal compression could be an alternative choice applied on industrial compressor and compressed air energy storage (CAES). This paper proposed a new kind of piston to perform isothermal compression. Surface area of such isothermal piston structure is larger. A certain amount of fluid at the chamber bottom absorbs the heat from the isothermal piston. Heat transfer between piston and fluid during compression is investigated. Air pressure is measured to validate the effectiveness of this proposed piston structure in heat transfer. Compression work of the proposed isothermal piston and conventional one is compared. One issue of this comparison is that air-liquid dissolution can affect the pressure and compression work. The influence of dissolution is quantified with Henry’s Law. Quantitative analysis is performed to determine that heat transfer is the dominant factor affecting the pressure and compression work. Some simple experiments are described in this paper, which shed light on that heat transfer could be significantly improved adopting this proposed isothermal piston.
► Luminescent fibers—Luminescent silk fibers were synthesized. ► Antibacterial—The prepared Ag nanocluster composite silk fibers possessed antibacterial ability. ► In situ growth—It is a simple, ...low-cost and less time-consuming method for preparing fluorescent silk fibers.
The combination of metal nanoclusters with bulk materials is an effective way to achieve better properties of Ag nanoclusters and widening their applications. The common-used Bottom-Up methods for achieving the combination of nanoparticles with bulk materials is inapplicable to the Ag nanoclusters involved systems because the excessive surface modification of Ag nanoclusters tends to form nano-sized aggregates which will lose their luminescence. To solve this, we developed a method for in situ synthesis of Ag nanoclusters on the silk fibers by the ultraviolet light-induced reduction. It not only realized the in situ synthesis of Ag nanoclusters but also finished the combination of Ag nanoclusters and silk fibers. This Ag nanocluster composite silk fibers owned luminescence with the emission band at about 550nm. In addition, we found this novel Ag nanocluster composite silk fibers had strong antimicrobial ability against Escherichia coli and Staphyloccocus aureus. This method is also applicable for most natural and artificial fibers.
A kind of functional noble metal nanoparticles and metal/organic semiconductor composite nanomaterials, Ag nanoparticles (AgNPs, 6–10 nm in diameter) decorated small-sized ...Ag-tetracyano-p-tetrafluoroquinodimethane (AgTCNQF4) nanorods (150–400 nm in length and 60–100 nm in diameter), have been successfully synthesized through a rapid microemulsion reaction between TCNQF4 molecules and an AgNP colloid under a soft template of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol). The morphology, chemical structure, and elemental composition of the prepared AgNPs–AgTCNQF4 composite nanorods were studied by transmission electron microscopy, selected-area electron diffraction, and X-ray photoelectron spectroscopy. The real-time ultraviolet–visible spectroscopy assisted with two-dimensional correlation spectroscopic analysis was employed to explore the growth of AgNPs–AgTCNQF4 composite nanorods in microemulsion. These composite nanorods display the photoinduced charge transfer (CT) property from the monoanion (TCNQF4 –) to dianion (TCNQF4 2–) selectively under 532 nm light irradiation. The larger content of AgNPs on the surface of AgTCNQF4 led to the higher conversion of dianion due to the plasmon-assisted photocatalysis. This photoelectric composite material is promising for the applications of light-writing data storage and photocatalysis.
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