14 research outputs found
Optical Properties of Dispersed Aerosols in the Near Ultraviolet (355 nm): Measurement Approach and Initial Data
An aerosol albedometer combining cavity ring-down spectroscopy
(CRDS) with integrating sphere nephelometry was developed for use
at λ = 355 nm. The instrument measures extinction and scattering
coefficients of dispersed particulate matter in the near ultraviolet
(UV) spectral region. Several samples have been analyzed, including:
ammonium sulfate, secondary organic aerosols (SOA) resulting from
the ozonolysis of α-pinene and photooxidation of toluene, redispersed
soil dust samples, biomass burning aerosols, and ambient aerosols.
When particle size and number density were experimentally controlled,
extinction coefficients and scattering coefficients were found to
have a linear relationship with particle number concentration, in
good agreement with light scattering theory. For ammonium sulfate
and pinene samples, extinction cross sections for size-selected (<i>D</i><sub>p</sub> = 300 nm) samples were within the range of
1.65–2.60 × 10<sup>–9</sup> cm<sup>2</sup> with
the largest value corresponding to ammonium sulfate and the lowest
value for pinene SOA. The scattering cross sections of pinene and
ammonium sulfate aerosols were indistinguishable from the extinction
cross sections, indicating that these particle types had minimal light
absorption at 355 nm. However, soil dusts and biomass burning aerosols
showed significant absorption with single scatter albedo (SSA) between
0.74 and 0.84. Ambient aerosols also had transient absorption at 355
nm that correlated well with a particle-soot absorption photometer
(PSAP) measuring visible light absorption
Multiple Water-in-Oil-in-Water Emulsion Gels Based on Self-Assembled Saponin Fibrillar Network for Photosensitive Cargo Protection
A gelled
multiple water-in-oil-in-water (W<sub>1</sub>/O/W<sub>2</sub>) emulsion
was successfully developed by the unique combination
of emulsifying and gelation properties of natural glycyrrhizic acid
(GA) nanofibrils, assembling into a fibrillar hydrogel network in
the continuous phase. The multiple emulsion gels had relatively homogeneous
size distribution, high yield (85.6–92.5%), and superior storage
stability. The multilayer interfacial fibril shell and the GA fibrillar
hydrogel in bulk can effectively protect the double emulsion droplets
against flocculation, creaming, and coalescence, thus contributing
to the multiple emulsion stability. Particularly, the highly viscoelastic
bulk hydrogel had a high storage modulus, which was found to be able
to strongly prevent the osmotic-driven water diffusion from the internal
water droplets to the external water phase. We show that these multicompartmentalized
emulsion gels can be used to encapsulate and protect photosensitive
water-soluble cargos by loading them into the internal water droplets.
These stable multiple emulsion gels based on natural, sustainable
saponin nanofibrils have potential applications in the food, pharmaceutical,
and personal care industries
Supplemental material - Astrocyte-microglia interaction through C3/C3aR pathway modulates neuropathic pain in rats model of chronic constriction injury
Supplemental material for Astrocyte-microglia interaction through C3/C3aR pathway modulates neuropathic pain in rats model of chronic constriction injury by Wanying Mou, Lulu Ma, Afang Zhu, Huan Cui, and Yuguang Huang in Molecular Pain</p
Controlled Hydrophobic Biosurface of Bacterial Cellulose Nanofibers through Self-Assembly of Natural Zein Protein
A novel,
highly biocompatible bacterial cellulose (BC)-zein composite
nanofiber with a controlled hydrophobic biosurface was successfully
developed through a simple and green solution impregnation method,
followed by evaporation-induced self-assembly (EISA) of adsorbed zein
protein. The surface hydrophobicity of the zein-modified BC nanofibers
could be controlled by simply changing the zein concentration, which
is able to tune the morphology of self-assembled zein structures after
EISA, thus affecting the surface roughness of composite membranes.
Zein self-assembly at low concentrations (5 mg/mL) resulted in the
formation of hierarchical zein structures (spheres and bicontinuous
sponges) on the BC surface, thus increasing the surface roughness
and leading to high hydrophobicity (the water contact angle reached
110.5°). However, at high zein concentrations, these large zein
spheres assembled into a flat zein film, which decreased the surface
roughness and hydrophobicity of membranes. The homogeneous incorporation
of zein structures on the BC surface by hydrogen bonding did not significantly
change the internal structure and mechanical performance of BC nanofibers.
In comparison with pure BC, the BC-zein nanofibers had a better biocompatibility,
showing a significantly increased adhesion and proliferation of fibroblast
cells. This is probably due to the rough surface structure of BC-zein
nanofibers as well as the high biocompatibility of natural zein protein.
The novel BC-zein composite nanofibers with controlled surface roughness
and hydrophobicity could be of particular interest for the design
of BC-based biomaterials and biodevices that require specific surface
properties and adhesion
Responsive Emulsion Gels with Tunable Properties Formed by Self-Assembled Nanofibrils of Natural Saponin Glycyrrhizic Acid for Oil Structuring
Saponin nanofibrils assembled from
natural glycyrrhizic acid (GA)
have been recently shown to be an effective structurant for edible
oil structuring. This work showed that the microstructure and mechanical
properties of the novel emulsion gels formed by GA fibrils could be
well tuned by oil phase polarity. For more polar oils (algal oil),
the GA fibrils had a higher affinity to the oil–water interface,
showing a faster adsorption kinetics, thus leading to the formation
of fine multilayer emulsion droplets with smaller droplet size. Accordingly,
the emulsion gels had a denser network microstructure and higher mechanical
strength, which should be attributed to the fact that the smaller
emulsion droplets could be packed more tightly within the continuous
network, providing stronger interdroplet interactions, and thereby
contribute to reinforcing the gel matrix. In addition, all emulsion
gels had interesting thermoresponsive behavior, independent of oil
phase, which is probably due to the thermoreversibility of the hydrogen-bond
fibrillar network in the continuous phase
DataSheet_1_Cotton Fusarium wilt diagnosis based on generative adversarial networks in small samples.pdf
This study aimed to explore the feasibility of applying Generative Adversarial Networks (GANs) for the diagnosis of Verticillium wilt disease in cotton and compared it with traditional data augmentation methods and transfer learning. By designing a model based on small-sample learning, we proposed an innovative cotton Verticillium wilt disease diagnosis system. The system uses Convolutional Neural Networks (CNNs) as feature extractors and applies trained GAN models for sample augmentation to improve classification accuracy. This study collected and processed a dataset of cotton Verticillium wilt disease images, including samples from normal and infected plants. Data augmentation techniques were used to expand the dataset and train the CNNs. Transfer learning using InceptionV3 was applied to train the CNNs on the dataset. The dataset was augmented using GAN algorithms and used to train CNNs. The performances of the data augmentation, transfer learning, and GANs were compared and analyzed. The results have demonstrated that augmenting the cotton Verticillium wilt disease image dataset using GAN algorithms enhanced the diagnostic accuracy and recall rate of the CNNs. Compared to traditional data augmentation methods, GANs exhibit better performance and generated more representative and diverse samples. Unlike transfer learning, GANs ensured an adequate sample size. By visualizing the images generated, GANs were found to generate realistic cotton images of Verticillium wilt disease, highlighting their potential applications in agricultural disease diagnosis. This study has demonstrated the potential of GANs in the diagnosis of cotton Verticillium wilt disease diagnosis, offering an effective approach for agricultural disease detection and providing insights into disease detection in other crops.</p
Bottom-up Approach toward Single-Crystalline VO<sub>2</sub>‑Graphene Ribbons as Cathodes for Ultrafast Lithium Storage
Although lithium ion batteries have
gained commercial success owing
to their high energy density, they lack suitable electrodes capable
of rapid charging and discharging to enable a high power density critical
for broad applications. Here, we demonstrate a simple bottom-up approach
toward single crystalline vanadium oxide (VO<sub>2</sub>) ribbons
with graphene layers. The unique structure of VO<sub>2</sub>-graphene
ribbons thus provides the right combination of electrode properties
and could enable the design of high-power lithium ion batteries. As
a consequence, a high reversible capacity and ultrafast charging and
discharging capability is achieved with these ribbons as cathodes
for lithium storage. A full charge or discharge is capable in 20 s.
More remarkably, the resulting electrodes retain more than 90% of
the initial capacity after cycling more than 1000 times at an ultrahigh
rate of 190C, providing the best reported rate performance for cathodes
in lithium ion batteries to date
Bottom-up Approach toward Single-Crystalline VO<sub>2</sub>‑Graphene Ribbons as Cathodes for Ultrafast Lithium Storage
Although lithium ion batteries have
gained commercial success owing
to their high energy density, they lack suitable electrodes capable
of rapid charging and discharging to enable a high power density critical
for broad applications. Here, we demonstrate a simple bottom-up approach
toward single crystalline vanadium oxide (VO<sub>2</sub>) ribbons
with graphene layers. The unique structure of VO<sub>2</sub>-graphene
ribbons thus provides the right combination of electrode properties
and could enable the design of high-power lithium ion batteries. As
a consequence, a high reversible capacity and ultrafast charging and
discharging capability is achieved with these ribbons as cathodes
for lithium storage. A full charge or discharge is capable in 20 s.
More remarkably, the resulting electrodes retain more than 90% of
the initial capacity after cycling more than 1000 times at an ultrahigh
rate of 190C, providing the best reported rate performance for cathodes
in lithium ion batteries to date
Nitrogen-Doped Graphene with Pyridinic Dominance as a Highly Active and Stable Electrocatalyst for Oxygen Reduction
The nitrogen-doped graphene (NG)
with dominance of the pyridinic-N
configuration is synthesized via a straightforward process including
chemical vapor deposition (CVD) growth of graphene and postdoping
with a solid nitrogen precursor of graphitic C<sub>3</sub>N<sub>4</sub> at elevated temperature. The NG fabricated from CVD-grown graphene
contains a high N content up to 6.5 at. % when postdoped at 800 °C
but maintains high crystalline quality of graphene. The obtained NG
exhibits high activity, long-standing stability, and outstanding crossover
resistance for electrocatalysis of oxygen reduction reaction (ORR)
in alkaline medium. The NG treated at 800 °C shows the best ORR
performance. Further study of the dependence of ORR activity on different
N functional groups in these metal-free NG electrodes provides deeper
insights into the origin of ORR activity. Our results reveal that
the pyridinic-N tends to be the most active N functional group to
facilitate ORR at low overpotential via a four-electron pathway
Carbon Nitrogen Nanotubes as Efficient Bifunctional Electrocatalysts for Oxygen Reduction and Evolution Reactions
Oxygen reduction and evolution reactions
are essential for broad range of renewable energy technologies such
as fuel cells, metal-air batteries and hydrogen production through
water splitting, therefore, tremendous effort has been taken to develop
excellent catalysts for these reactions. However, the development
of cost-effective and efficient bifunctional catalysts for both reactions
still remained a grand challenge. Herein, we report the electrocatalytic
investigations of bamboo-shaped carbon nitrogen nanotubes (CNNTs)
having different diameter distribution synthesized by liquid chemical
vapor deposition technique using different nitrogen containing precursors.
These CNNTs are found to be efficient bifunctional electrocatalyst
for oxygen reduction and evolution reactions. The electrocatalytic
activity strongly depends on the nanotube diameter as well as nitrogen
functionality type. The higher diameter CNNTs are more favorable for
these reactions. The increase in nanotube diameter itself enhances
the catalytic activity by lowering the oxygen adsorption energy, better
conductivity, and further facilitates the reaction by increasing the
percentage of catalytically active nitrogen moieties in CNNTs