14 research outputs found
List of relief items in urgent need by Shashi Temporary Electric Lights House [China], April 21, 1946 = 中國沙市臨時電燈厰急需救濟物資表, 1946年4月21日
A list of relief items in urgent need by Shashi Temporary Electric Lights House, dated as April 21, 1946.Galaida Survey Materia
The enhancement of emission intensity and enlargement of color gamut by a simple local structure substitution with highly thermal stability preserved
The local crystal structure engineering becomes an important strategy to design new phosphors with enhanced optical and thermal performance of white light-emitting diodes. Herein, a series of Na3Sc2(PO4)3: Eu2+ and KyNa2.97-ySc2(PO4)3: 0.03Eu2+ phosphors were synthesized via traditional high temperature solid-state reaction method. X-ray powder diffraction analysis and Rietveld refinement provide insight in the detailed crystal structure. Furthermore, Eu2+ doped Na3Sc2(PO4)3 exhibits bright blue emission in 400–540 nm spectral range with a maximum value at ~ 460 nm under n-UV light excitation. The concentration quenching mechanism of Eu2+ in Na3Sc2(PO4)3 is certified to be a dipole-dipole interaction. Additionally, crystal structure tailoring is a potential strategy to design new phosphors for particular applications. Therefore, the effects of K+ substitution on the structure and photoluminescence of Eu2+ activated Na3Sc2(PO4)3 is presented in detail. Rietveld refinement data revealed that unit cell volume and Na/K–O band length increase when K+ occupy the Na+ sites. This sensitive local structure resulted in a considerable enhancement of the photoluminescence intensity of Eu2+. Incorporation of K+ in the crystal structure is a feasible route to realize fine-tuning of emission color and broaden the color gamut. In the meantime, Na2.7K0.27Sc2(PO4)3: 0.03Eu2+ phosphor exhibits excellent thermal stability at high temperature over a significant radiative recombination of energy transfer from traps to Eu2+. These results confirm that Na2.7K0.27Sc2(PO4)3: 0.03Eu2+ phosphor might be used as a blue component in n-UV chip activated white light-emitting diodes for the next-generation of indoor solid-state lighting applications. © 2019 Elsevier B.V
Thermally Stable White Emitting Eu<sup>3+</sup> Complex@Nanozeolite@Luminescent Glass Composite with High CRI for Organic-Resin-Free Warm White LEDs
Nowadays,
it is still a great challenge for lanthanide complexes to be applied
in solid state lighting, especially for high-power LEDs because they
will suffer severe thermal-induced luminescence quenching and transmittance
loss when LEDs are operated at high current. In this paper, we have
not only obtained high efficient and thermally chemical stable red
emitting hybrid material by introducing europium complex into nanozeolite
(NZ) functionalized with the imidazolium-based stopper but also abated
its thermal-induced transmittance loss and luminescence quenching
behavior via coating it onto a heat-resistant luminescent glass (LG)
with high thermal conductivity (1.07 W/mK). The results show that
the intensity at 400 K for Eu(PPO)<sub><i>n</i></sub>-C<sub>4</sub>Si@NZ@LG remains 21.48% of the initial intensity at 300 K,
which is virtually 153 and 13 times the intensity of Eu(PPO)<sub>3</sub>·2H<sub>2</sub>O and Eu(PPO)<sub><i>n</i></sub>-C<sub>4</sub>Si@NZ, respectively. Moreover, an organic-resin-free warm
white LEDs device with a low CCT of 3994K, a high Ra of 90.2 and R9
of 57.9 was successfully fabricated simply by combining NUV-Chip-On-Board
with a warm white emitting glass-film composite (i.e., yellowish-green
emitting luminescent glass coated with red emitting hybrid film).
Our method and results provide a feasible and promising way for lanthanide
complexes to be used for general illumination in the future
Programming Cell Adhesion for On-Chip Sequential Boolean Logic Functions
Programmable remodelling of cell
surfaces enables high-precision
regulation of cell behavior. In this work, we developed in vitro constructed
DNA-based chemical reaction networks (CRNs) to program on-chip cell
adhesion. We found that the RGD-functionalized DNA CRNs are entirely
noninvasive when interfaced with the fluidic mosaic membrane of living
cells. DNA toehold with different lengths could tunably alter the
release kinetics of cells, which shows rapid release in minutes with
the use of a 6-base toehold. We further demonstrated the realization
of Boolean logic functions by using DNA strand displacement reactions,
which include multi-input and sequential cell logic gates (AND, OR,
XOR, and AND-OR). This study provides a highly generic tool for self-organization
of biological systems
Preservation of DNA Nanostructure Carriers: Effects of Freeze–Thawing and Ionic Strength during Lyophilization and Storage
DNA nanostructures have attracted
wide interest in biomedical applications,
especially as nanocarriers for drug delivery. Therefore, it is important
to ensure the structural integrity of DNA nanostructures under ambient
temperature storage. In this study, we examined lyophilization-based
preservation of DNA nanostructures by investigating the structural
integrity of different DNA nanostructures reconstituted from lyophilization.
We demonstrated that lyophilization under appropriate ionic strength
is amenable to the storage of DNA nanostructures. Compared with that
stored in liquid solution, DNA nanostructure carriers reconstituted
from lyophilization showed significantly better structural integrity
after an accelerated aging test equivalent to 100-day room-temperature
storage
DNA Hydrogel with Aptamer-Toehold-Based Recognition, Cloaking, and Decloaking of Circulating Tumor Cells for Live Cell Analysis
Circulating tumor
cells (CTCs) contain molecular information on
the primary tumor and can be used for predictive cancer diagnostics.
Capturing rare live CTCs and their quantification in whole blood remain
technically challenging. Here we report an aptamer-trigger clamped
hybridization chain reaction (atcHCR) method for in situ identification
and subsequent cloaking/decloaking of CTCs by porous DNA hydrogels.
These decloaked CTCs were then used for live cell analysis. In our
design, a DNA staple strand with aptamer-toehold biblocks specifically
recognizes epithelial cell adhesion molecule (EpCAM) on the CTC surface
that triggers subsequent atcHCR via toehold-initiated branch migration.
Porous DNA hydrogel based-cloaking of single/cluster of CTCs allows
capturing of living CTCs directly with minimal cell damage. The ability
to identify a low number of CTCs in whole blood by DNA hydrogel cloaking
would allow high sensitivity and specificity for diagnosis in clinically
relevant settings. More significantly, decloaking of CTCs using controlled
and defined chemical stimuli can release living CTCs without damages
for subsequent culture and live cell analysis. We expect this liquid
biopsy tool to open new powerful and effective routes for cancer diagnostics
and therapeutics