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Bacteria photosensitized by intracellular gold nanoclusters for solar fuel production.
The demand for renewable and sustainable fuel has prompted the rapid development of advanced nanotechnologies to effectively harness solar power. The construction of photosynthetic biohybrid systems (PBSs) aims to link preassembled biosynthetic pathways with inorganic light absorbers. This strategy inherits both the high light-harvesting efficiency of solid-state semiconductors and the superior catalytic performance of whole-cell microorganisms. Here, we introduce an intracellular, biocompatible light absorber, in the form of gold nanoclusters (AuNCs), to circumvent the sluggish kinetics of electron transfer for existing PBSs. Translocation of these AuNCs into non-photosynthetic bacteria enables photosynthesis of acetic acid from CO2. The AuNCs also serve as inhibitors of reactive oxygen species (ROS) to maintain high bacterium viability. With the dual advantages of light absorption and biocompatibility, this new generation of PBS can efficiently harvest sunlight and transfer photogenerated electrons to cellular metabolism, realizing CO2 fixation continuously over several days
Removal of sulfamethoxazole and sulfapyridine by carbon nanotubes in fixed-bed columns
Sulfamethoxazole (SMX) and sulfapyridine (SPY), two representative sulfonamide antibiotics, have gained increasing attention because of the ecological risks these substances pose to plants, animals, and humans. This work systematically investigated the removal of SMX and SPY by carbon nanotubes (CNTs) in fixed-bed columns under a broad range of conditions including: CNT incorporation method, solution pH, bed depth, adsorbent dosage, adsorbate initial concentration, and flow rate. Fixed-bed experiments showed that pH is a key factor that affects the adsorption capacity of antibiotics to CNTs. The Bed Depth Service Time model describes well the relationship between service time and bed depth and can be used to design appropriate column parameters. During fixed-bed regeneration, small amounts of SMX (3%) and SPY (9%) were irreversibly bonded to the CNT/sand porous media, thus reducing the column capacity for subsequent reuse from 67.9 to 50.4 mg g−1 for SMX and from 91.9 to 72.9 mg g−1 for SPY. The reduced column capacity resulted from the decrease in available adsorption sites and resulting repulsion (i.e., blocking) of incoming antibiotics from those previously adsorbed. Findings from this study demonstrate that fixed-bed columns packed with CNTs can be efficiently used and regenerated to remove antibiotics from water
Scalable Preparation of SrTiO3 Submicro-wires from Layered Titanate Nanowires
AbstractSrTiO3 submicro-wires were prepared by the reaction of layered titanate nanowires with Sr (OH)2 powder in an autoclave. The wires were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Ultra-violet visible (UV-vis), photoluminescence (PL) and Raman spectroscopy. The XRD measurement shows that the prepared SrTiO3 submicro-wires hardly have impurity phases. The SEM and TEM images demonstrate that the scalable wires, which need to be processed at the reaction temperature of 180 °C for about 48 hours, are not composed of single crystals. The PL shows that the wire-like SrTiO3 has emission peaks at the wavelengths of 568 and 585 nm. Further, the Raman spectroscopy reveals structural changes in the products through different reaction time
Infrared carpet cloak designed with uniform silicon grating structure
Through a particularly chosen coordinate transformation, we propose an
optical carpet cloak that only requires homogeneous anisotropic dielectric
material. The proposed cloak could be easily imitated and realized by
alternative layers of isotropic dielectrics. To demonstrate the cloaking
performance, we have designed a two-dimensional version that a uniform silicon
grating structure fabricated on a silicon-on-insulator wafer could work as an
infrared carpet cloak. The cloak has been validated through full wave
electromagnetic simulations, and the non-resonance feature also enables a
broadband cloaking for wavelengths ranging from 1372 to 2000 nm.Comment: 11 pages, 4 figure
KD-EKF: A Consistent Cooperative Localization Estimator Based on Kalman Decomposition
In this paper, we revisit the inconsistency problem of EKF-based cooperative
localization (CL) from the perspective of system decomposition. By transforming
the linearized system used by the standard EKF into its Kalman observable
canonical form, the observable and unobservable components of the system are
separated. Consequently, the factors causing the dimension reduction of the
unobservable subspace are explicitly isolated in the state propagation and
measurement Jacobians of the Kalman observable canonical form. Motivated by
these insights, we propose a new CL algorithm called KD-EKF which aims to
enhance consistency. The key idea behind the KD-EKF algorithm involves perform
state estimation in the transformed coordinates so as to eliminate the
influencing factors of observability in the Kalman observable canonical form.
As a result, the KD-EKF algorithm ensures correct observability properties and
consistency. We extensively verify the effectiveness of the KD-EKF algorithm
through both Monte Carlo simulations and real-world experiments. The results
demonstrate that the KD-EKF outperforms state-of-the-art algorithms in terms of
accuracy and consistency
A convenient tandem one-pot synthesis of donor-acceptor-type triphenylene 2,3-dicarboxylic esters from diarylacetylene
A tandem one-pot method for the direct synthesis of polysubstituted triphenylene 2,3-dicarboxylic esters with different substitution patterns was developed by enyne metathesis of diarylacetylene, followed by Diels–Alder, aromatization and a cyclization cascade
Acceptance Of Qr Code In Taiwan: An Extension Of The Technology Acceptance Model
The development and application of QR code is quite advanced in Japan and Korea; in contrast, at the time when the QR code was introduced in Taiwan, lack of mobile phone support and the limited applications of QR code meant that it was not immediately popularized. In recent years, the growing popularity of smart phones has enhanced the various applications of QR code, not only providing the information to the user, but also performing navigation, marketing and ticketing functions, to name a few. This study is based on the Technology Acceptance Model, with Social Influence, Facilitating Conditions, Awareness Knowledge, Operation Knowledge and Price as the usage factors, and by verifying the structural modelling through public surveys and analyzing the importance of the Acceptance Model and other influences of users in Taiwan as the driving factors in incorporating QR code applications in the government, telecommunication carrier and business spheres
ERNIE-ViL: Knowledge Enhanced Vision-Language Representations Through Scene Graph
We propose a knowledge-enhanced approach, ERNIE-ViL, which incorporates
structured knowledge obtained from scene graphs to learn joint representations
of vision-language. ERNIE-ViL tries to build the detailed semantic connections
(objects, attributes of objects and relationships between objects) across
vision and language, which are essential to vision-language cross-modal tasks.
Utilizing scene graphs of visual scenes, ERNIE-ViL constructs Scene Graph
Prediction tasks, i.e., Object Prediction, Attribute Prediction and
Relationship Prediction tasks in the pre-training phase. Specifically, these
prediction tasks are implemented by predicting nodes of different types in the
scene graph parsed from the sentence. Thus, ERNIE-ViL can learn the joint
representations characterizing the alignments of the detailed semantics across
vision and language. After pre-training on large scale image-text aligned
datasets, we validate the effectiveness of ERNIE-ViL on 5 cross-modal
downstream tasks. ERNIE-ViL achieves state-of-the-art performances on all these
tasks and ranks the first place on the VCR leaderboard with an absolute
improvement of 3.7%.Comment: Paper has been published in the AAAI2021 conferenc
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