37 research outputs found
High-Thermal-Conductivity and High-Fluidity Heat Transfer Emulsion with 89 wt % Suspended Liquid Metal Microdroplets
Colloidal suspensions of thermally conductive particles
in a carrier
fluid are considered promising heat transfer fluids for various thermal
energy transfer applications, such as transportation, plants, electronics,
and renewable energy systems. The thermal conductivity (k) of the particle-suspended fluids can be improved substantially
by increasing the concentration of conductive particles above a “thermal
percolation threshold,” which is limited because of the vitrification
of the resulting fluid at the high particle loadings. In this study,
eutectic Ga–In liquid metal (LM) was employed as a soft high-k filler dispersed as microdroplets at high loadings in
paraffin oil (as a carrier fluid) to produce an emulsion-type heat
transfer fluid with the combined advantages of high thermal conductivity
and high fluidity. Two types of the LM-in-oil emulsions, which were
produced via the probe-sonication and rotor–stator homogenization
(RSH) methods, demonstrated significant improvements in k, i.e., Δk ∼409 and ∼261%, respectively,
at the maximum investigated LM loading of 50 vol % (∼89 wt
%), attributed to the enhanced heat transport via high-k LM fillers above the percolation threshold. Despite the high filler
loading, the RSH-produced emulsion retained remarkably high fluidity,
with a relatively low viscosity increase and no yield stress, demonstrating
its potential as a circulatable heat transfer fluid
High-Thermal-Conductivity and High-Fluidity Heat Transfer Emulsion with 89 wt % Suspended Liquid Metal Microdroplets
Colloidal suspensions of thermally conductive particles
in a carrier
fluid are considered promising heat transfer fluids for various thermal
energy transfer applications, such as transportation, plants, electronics,
and renewable energy systems. The thermal conductivity (k) of the particle-suspended fluids can be improved substantially
by increasing the concentration of conductive particles above a “thermal
percolation threshold,” which is limited because of the vitrification
of the resulting fluid at the high particle loadings. In this study,
eutectic Ga–In liquid metal (LM) was employed as a soft high-k filler dispersed as microdroplets at high loadings in
paraffin oil (as a carrier fluid) to produce an emulsion-type heat
transfer fluid with the combined advantages of high thermal conductivity
and high fluidity. Two types of the LM-in-oil emulsions, which were
produced via the probe-sonication and rotor–stator homogenization
(RSH) methods, demonstrated significant improvements in k, i.e., Δk ∼409 and ∼261%, respectively,
at the maximum investigated LM loading of 50 vol % (∼89 wt
%), attributed to the enhanced heat transport via high-k LM fillers above the percolation threshold. Despite the high filler
loading, the RSH-produced emulsion retained remarkably high fluidity,
with a relatively low viscosity increase and no yield stress, demonstrating
its potential as a circulatable heat transfer fluid
High-Thermal-Conductivity and High-Fluidity Heat Transfer Emulsion with 89 wt % Suspended Liquid Metal Microdroplets
Colloidal suspensions of thermally conductive particles
in a carrier
fluid are considered promising heat transfer fluids for various thermal
energy transfer applications, such as transportation, plants, electronics,
and renewable energy systems. The thermal conductivity (k) of the particle-suspended fluids can be improved substantially
by increasing the concentration of conductive particles above a “thermal
percolation threshold,” which is limited because of the vitrification
of the resulting fluid at the high particle loadings. In this study,
eutectic Ga–In liquid metal (LM) was employed as a soft high-k filler dispersed as microdroplets at high loadings in
paraffin oil (as a carrier fluid) to produce an emulsion-type heat
transfer fluid with the combined advantages of high thermal conductivity
and high fluidity. Two types of the LM-in-oil emulsions, which were
produced via the probe-sonication and rotor–stator homogenization
(RSH) methods, demonstrated significant improvements in k, i.e., Δk ∼409 and ∼261%, respectively,
at the maximum investigated LM loading of 50 vol % (∼89 wt
%), attributed to the enhanced heat transport via high-k LM fillers above the percolation threshold. Despite the high filler
loading, the RSH-produced emulsion retained remarkably high fluidity,
with a relatively low viscosity increase and no yield stress, demonstrating
its potential as a circulatable heat transfer fluid
MOESM3 of A novel graph theoretical approach for modeling microbiomes and inferring microbial ecological relationships
Additional file 3 This file contains list of split graphs for Crohn’s disease patients from tissue group
MOESM2 of A novel graph theoretical approach for modeling microbiomes and inferring microbial ecological relationships
Additional file 2 This file contains associations between bacterial genera and their microbial pathways with KO density in Crohn’s disease tissue
MOESM1 of A novel graph theoretical approach for modeling microbiomes and inferring microbial ecological relationships
Additional file 1 This file contains Inter-bacteria correlations in all sample groups at genus level
Scalable Dry Process for Fabricating a Na Superionic Conductor-Type Solid Electrolyte Sheet
The cost reduction and mass production of oxide-based
solid electrolytes
are critical for the commercialization of all-solid-state batteries.
In this study, an environmentally friendly, low-cost, and high-density
oxide-based Na superionic conductor-type solid electrolyte sheet was
fabricated via a dry process without the use of any solvent. The polytetrafluoroethylene
(PTFE), used as a binder, was transformed into thin thread-like structures
via shear force, resulting in a flexible solid electrolyte sheet.
The solid electrolyte powder quantity was limited to 50 wt % for fabricating
a uniform green sheet via the wet process. However, when the dry process
was employed for green sheet fabrication, the solid electrolyte powder
quantity could be increased to values exceeding 95 wt %. Therefore,
the green sheets produced by using the dry process demonstrated a
higher density than those fabricated by using the wet process. The
binder content and particle size affected the ionic conductivity of
a solid electrolyte sheet fabricated via a dry process. The sheet
obtained via the blending of 3 wt % PTFE binder with a solid electrolyte
powder, finely ground using a planetary ball mill, which exhibited
the highest total ionic conductivity of 1.03 mS cm–1
On-Site Remote Monitoring System with NIR Signal-Based Detection of Infectious Disease Virus in Opaque Salivary Samples
Infectious
disease viruses, such as foot-and-mouth disease virus
(FMDV), are highly contagious viruses that cause significant socioeconomic
damage upon spreading. Developing an on-site diagnostic tool for early
clinical detection and real-time surveillance of FMDV outbreaks is
essential to prevent the further spread of the disease. However, early
diagnosis of FMDV is still challenging due to the limited sensitivity
and time-consuming manual result entry of commercial on-site tests
for salivary samples. Here, we report a near-infrared (NIR) signal
nanoprobe-based highly accurate detection and remote monitoring system
toward FMDVs, which automates the analysis and reporting of diagnosis
data. The NIR signal lateral flow immunoassay (LFA) was assembled
with a nanoprobe with a stable emission intensity at 800 nm, minimizing
the interference signal of opaque salivary samples. We investigated
the clinical applicability of the NIR signal LFA at biosafety level
3 (BSL-3) laboratories using 147 opaque salivary samples. The NIR
signal LFA achieved a 32-fold lower limit of detection (LOD) than
a commercial LFA in detecting live FMDVs, including all isolates occurring
in the Republic of Korea during 2010–2017. Our results showed
that the NIR signal LFA successfully discriminated the FMDV-positive
clinical salivary samples from healthy controls with a sensitivity
of 96.9%, specificity of 100.0%, and AUC (area under the receiver
operator characteristic curve) value of 0.999. Finally, we substantiated
the real-time collection of diagnostic results using a customized
portable NIR reader at nine different laboratories of government-certified
quarantine institutions for foot-and-mouth disease (FMD)
Additional file 1 of Photosensitizing deep-seated cancer cells with photoprotein-conjugated upconversion nanoparticles
Supplementary Material 1: Additional file 1: Figure S1. Elemental analysis of CS-UCNPs by energy-dispersive X-ray spectroscopy. Figure S2. X-ray diffraction patterns of oleic acid-capped Co-UCNPs and CS-UCNPs. Figure S3. TEM image of Co-UCNPs. Figure S4. TEM images of Co-UCNPs and CS-UCNPs. Figure S5. TEM images of CS-UCNPs. Figure S6. Effect of Yb3+ concentratons on the ET efficiency in UCNPs. Figure S7. SDS-PAGE and fluorescent gel images of KR and KR-LP. Figure S8. FT-IR spectrum of KR-LP. Figure S9.In vitro stability of CS-UCNP-KR-LP over a two-week period using PL intensity and polydispersity index. Figure S10. Effect of Er3+ concentrations (2−10%) in CS-UCNP-NH2 on the PL decay time. Figure S11. Flow cytometric analysis of intracellular ROS generation using DCFDA with CS-UCNPs or Co-UCNPs. Figure S12. MTT assay of cell viability according to nanocomposite concentration for 5 cancer cell lines. Figure S13. MTT assay of cell viability according to irradiation time for 5 cancer cell lines. Figure S14. MTT assay of cell viability of MCF-7 cells without either NIR irradiation or nanocomposites. Figure S15. Measurement of cellular uptake of three different CS-UCNPs using ICP-MS in cancer cells. Figure S16. Experimental setup for evaluating the tissue-penetrating effect of NIR irradiation on CS-UCNP-KR-LP in MCF-7 cells
Efficient Cobalt Catalyst for Ambient-Temperature Nitrile Dihydroboration, the Elucidation of a Chelate-Assisted Borylation Mechanism, and a New Synthetic Route to Amides
N,N-Diborylamines have emerged
as promising reagents in organic synthesis; however, their efficient
preparation and full synthetic utility have yet to be realized. To
address both shortcomings, an effective catalyst for nitrile dihydroboration
was sought. Heating CoCl2 in the presence of PyEtPDI afforded the six-coordinate Co(II) salt, [(PyEtPDI)CoCl][Cl].
Upon adding 2 equiv of NaEt3BH, hydride transfer to one
chelate imine functionality was observed, resulting in the formation
of (κ4-N,N,N,N-PyEtIPCHMeNEtPy)Co. Single-crystal X-ray diffraction and
density functional theory calculations revealed that this compound
possesses a low-spin Co(II) ground state featuring antiferromagnetic
coupling to a singly reduced imino(pyridine) moiety. Importantly,
(κ4-N,N,N,N-PyEtIPCHMeNEtPy)Co was found to catalyze the dihydroboration
of nitriles using HBPin with turnover frequencies of up to 380 h–1 at ambient temperature. Stoichiometric addition experiments
revealed that HBPin adds across the Co–Namide bond
to generate a hydride intermediate that can react with additional
HBPin or nitriles. Computational evaluation of the reaction coordinate
revealed that the B–H addition and nitrile insertion steps
occur on the antiferromagnetically coupled triplet spin manifold.
Interestingly, formation of the borylimine intermediate was found
to occur following BPin transfer from the borylated chelate arm to
regenerate (κ4-N,N,N,N-PyEtIPCHMeNEtPy)Co. Borylimine reduction is in
turn facile and follows the same ligand-assisted borylation pathway.
The independent hydroboration of alkyl and aryl imines was also demonstrated
at 25 °C. With a series of N,N-diborylamines in hand, their addition to carboxylic acids allowed
for the direct synthesis of amides at 120 °C, without the need
for an exogenous coupling reagent
