8 research outputs found
Research on Noise-Induced Characteristics of Unsteady Cavitation of a Jet Pump
The dynamic cavitation
characteristics of normal-temperature water
flowing through a transparent jet pump under different cavitation
conditions were experimentally studied by adjusting the pressure ratio.
The common results are presented at different pressure ratios, including
the temporal and spatial changes of the pressure and noise, together
with the visual observation of the cavitation unsteady behaviors using
a high-speed camera. The analyses on the measured data and images
reveal that the cavitation cloud is generated by periodic oscillations
of the jet traveling pressure wave and the bubble traveling pressure
wave. The oscillation of the two kinds of interface waves is caused
by the collapse of the bubbles, which is the main mechanism of the
bubble cloud shedding. As the pressure ratio increases, the maximum
length of the jet cloud and bubble cloud linearly decreases, while
their oscillation frequency increases gradually. Combined with the
cavitation-cloud visualization data and noise frequency analysis,
it is proposed that the strong impact between the jet traveling pressure
wave and the bubble traveling pressure wave is the main cause of noise.
Specially, the acoustic pressure reaches the maximum when the oscillation
frequency of the jet traveling pressure wave is the same as that of
the bubble traveling pressure wave. Also, the jet traveling pressure
wave has a great influence on the migration of bubbles in the cavity.
The results can provide guidance for the optimal operating condition
in cavitation applications such as jet aerator and quantitative addition
Full-Wood Utilization Strategy toward a Directional Luminescent Solar Concentrator
Luminescent solar concentrators (LSCs)
have proven to be highly
effective in enhancing the conversion efficiency of photovoltaic (PV)
cells. However, the traditional LSCs always suffer from self-absorption
and escape the losses of luminescence. To these challenges, this study
presents an ingenious all-wood-based LSC (W-LSC) with directional
light-concentrating capabilities. By converting lignin into fluorescent
carbon quantum dots (CQDs) and integrating them into transparent cellulose
channels in delignified wood, we achieved efficient directional luminescence
transmission in the W-LSC is achieved. The synthesized lignin-based
CQDs (L-CQDs) exhibited a large Stokes shift (0.63 eV) and a bright
yellow emission (540 nm). The prepared W-LSC possessed an external
optical efficiency (ηopt) along the longitudinal
(L) direction of 4.60% under a low irradiation intensity (40 mW·cm–2). Besides, contributed to the low thermal conductivity
(0.300 W·m–1·K–1) of
wood, the W-LSC maintained an ηopt of 4.03% at a
temperature of 65 °C. Furthermore, the W-LSC demonstrated high
tensile strength (424 MPa) and light transmission (85%). By leveraging
the advantages of wood, this approach provides a different solution
for enhancing solar energy utilization and advancing sustainable building
Evaluation of tumor microenvironmental immune regulation and prognostic in lung adenocarcinoma from the perspective of purinergic receptor P2Y13
Tumor-infiltrating immune cells (TICs) can serve as an important indicator to evaluate the prognosis and therapeutic response in lung adenocarcinoma (LUAD). The identification of mutated genes that can affect the abundance of TICs and prognosis has practical implications. In the presented study, tumor microenvironment (TME) scoring was performed by the ESTIMATE scoring system on 598 RNA transcripts selected from the TCGA database to determine the proportions of immune cells and stromal cells. The infiltration difference of TICs in LUAD samples was obtained by CIBERSORT. The ‘immuneeconv’ R software package, which integrates six latest algorithms, including TIMER, xCell, MCP-counter, CIBERSORT, EPIC and quanTIseq were used to verify the correlation between purinergic receptor P2Y13 (P2RY13) and immune cells. Based on RNA sequencing analysis of the Lewis lung cancer-bearing model in C57BL/6 mice and immunohistochemistry (IHC) of human LUAD tissues, the expression of P2RY13 and associated pathways were verified. It was shown that differentially expressed genes (DEGs) obtained by interactive analysis based on Immunescore and Stromalscore were significantly enriched in immune-related pathways. The expression of P2RY13 was significantly associated with prognosis and clinicopathological characteristics of LUAD patients. More importantly, this gene played an important role in maintaining the immune dominant environment and changing the regulation of TICs. P2RY13 expression was positively correlated with the infiltration of dendritic cells (DCs) in various of tumor tissues as validated by the PanglaoDB scRNA-seq database. Therefore, P2RY13 is expected to be a potential biomarker for predicting TME and the prognosis of LUAD after verification.</p
UV-Filtering Cellulose Nanocrystal/Carbon Quantum Dot Composite Films for Light Conversion in Glass Windows
The
development of energy-saving materials in buildings based on
biomass materials is a general consensus building construction of
low-carbon cities. Herein, we reported an effective ultraviolet (UV)-filtered
film, composed of carbon quantum dots (CDs) and cellulose nanocrystals
(CNC). The results showed that CNC had nanoscale dimensions with a
diameter of 20–50 nm and length of 250–450 nm, a high
crystallinity index of 84.7%, and enrichment of hydrogen bonds on
the surface. The photoluminescence spectra showed that lignin-based
carbon quantum dots (CDs) exhibited a long-wavelength red emission
(623 nm) and an uncommon narrow emission bandwidth (fwhm <30 nm).
In addition, the prepared UV-filtered film had strong mechanical tensile
properties, good UV light absorbing capability, and water resistance.
The optical test showed that the film also had highly optical transparency
(94%) and haze (70%). The excellent light management and conversion
function of this film provides a new user experience for soft, uniform,
healthy, and comfortable indoor sunlight lighting
Video1_A Superhydrophobic Moso Bamboo Cellulose Nano-Fibril Film Modified by Dopamine Hydrochloride.MP4
The moso bamboo fiber powder was used as raw material to prepare cellulose nano-fibril films, 5% of polyvinyl alcohol solution was used as a structural reinforcement agent, dopamine hydrochloride (DA) was used as a surface adhesive, and hexadecyl trimethoxy silane was used as a surface modifier. The superhydrophobic films were prepared by vacuum filtration and impregnation. The results showed that the water contact angle on the surface of the film could reach 156°. The microstructure and chemical composition of the film surface was further studied by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), and roughness measurement The scanning electron microscopy images showed that the nanofibers on the surface of Cellulose nanofibers film were arranged and randomly distributed, thus forming a dense network interwoven structure. In PDA hydrophobic modification solution, an Hexadecyltrimethoxysilane was hydrolyzed to a hexadecyl silanol to obtain the polar terminal hydroxyl of Hexadecyl silanol molecule. The -OCH3 terminal group of HDTMS reacted with hydroxyl/H2O to form a silanol (Si-OH) bond and further condensed to form a Si-O-Si network. In addition, due to the hydrophilicity of the surface of the nano cellulose film, a large amount of—OH was adsorbed on the surface of the nano cellulose film, resulted in the chemical connection between cetyl groups, thus realized the grafting of cetyl long-chain alkyl groups onto the fibers of the nano cellulose film.The film showed good self-cleaning and waterproof properties, which can be widely used in wet environment packaging and building.</p
Photoluminescent Transparent Wood with Excellent UV-Shielding Function
At present, light
transmission, energy saving, environmental
protection,
and UV-shielding materials are very important for optimizing indoor
living environment. Here, a fluorescent transparent wood (FTW) with
UV-shielding function was prepared by encapsulating a carbon quantum
dot and epoxy resin into a delignification wood template. FTW exhibits
excellent optical transmittance (about 91%), water absorption stability
(weight gain rate less than 9%), longitudinal tensile strength (139
MPa), and UV-shielding properties. Due to the photoluminescence characteristics
of the carbon quantum dot and the natural cellulose skeleton of wood,
FTW can show uniform luminescence under ultraviolet lamps. At the
same time, it has remarkable UV-shielding performance. This kind of
photoluminescent transparent wood with a UV-shielding function also
has the potential to be applied to fields such as electromagnetic
shielding and harmful gas detection
Bubble Diameter, Mass Transfer, and Bioreaction of Dynamic Membrane-Stirred Reactors
The
gas–liquid mass transfer of reactors is the
focus of
intensifying biochemical engineering. Hence, this paper develops a
dynamic membrane-stirred reactor to increase the gas–liquid
mass transfer efficiency (kLa) and improve bioreactions. Dynamic membrane coupling mixing and
aeration form uniform microbubbles to intensify gas–liquid
mass transfer. The optimal pore diameter and blade angle of the dynamic
membrane are 10 μm and 45°, respectively, providing more
uniform microbubbles, better gas–liquid mixing performance,
higher gas holdup, and better kLa. Compared with the traditional stirred reactor, the dynamic
membrane-stirred reactor reduces the energy consumption by 50% and
improves biomass and enzyme activity. The maximum dry cell weight
is 30.13 g·L–1, and the maximum specific cell
growth rate is 0.38 h–1, 48.9% higher and 31% higher
than the traditional reactor. To sum up, the unique structure of a
dynamic membrane-stirred reactor effectively reduces the bubble diameter
and improves kLa and
the bioreaction process
Unraveling the Early-Stage Ordering of Krypton Solid Bubbles in Molybdenum: A Multimodal Study
Self-organization
of defects such as fission gas bubbles in materials
can lead to high inventory capacity for fission gas storage and help
mitigate swelling caused by fission gases in nuclear fuel materials
under radiation in nuclear reactors. Here, we report the physical
mechanism of self-organization of krypton (Kr) gas bubbles in molybdenum
(Mo) under ion implantation. The ion fluence and temperature-dependent
formation of Kr solid bubble superlattice (SBS) in Mo were investigated
by using both synchrotron-based small-angle X-ray scattering (SAXS)
and transmission electron microscopy (TEM). Early stage self-organization
of gas bubbles is observed at a fluence of 2.5 × 1016 ions/cm2 at temperatures of 300–400 °C. The
bubble lattice constant increases with increasing implantation temperature
from 300 to 400 °C. Both experiments and atomic kinetic Monte
Carlo modeling indicate that the Kr solid bubbles are weakly ordered
in comparison to previously studied helium (He) gas bubble superlattice
(GBS) while the lattice constant are relatively smaller for Kr SBS
compared to that of He GBS. The irradiation conditions suggest that
spinodal decomposition, which is a form of phase separation, probably
precedes gas bubble ordering in Mo. Overall, our work sheds light
on the formation mechanism of noble gas superlattice toward the development
of radiation-tolerant materials which are important for the design
of advanced nuclear reactors
