255 research outputs found
Preparation of Material for Adsorption Ag(I) in the Solution
The application of silver in electronics, jewelry, catalytic and other industries often produces a large amount of silver-containing wastewater, which causes serious impact to the surrounding environment and human health, while silver has a certain economic value attached to it. Therefore, how to effectively treat and recover Ag(?) from the silver-containing wastewater is a hot topic of concern at present. In order to seek an efficient and environmentally friendly adsorbent, this paper compared the adsorption efficiency of purified, thermally modified, acid modified and thermally-acid modified Bentonite on silver, selected an economical and reasonable purified clay as a carrier, and then completed the preparation of modified Bentonite as well as the optimization of conditions with sodium silicate as a surfactant and 3-mercaptopropyltrimethoxysilane as a modifier. The experiments showed that under the conditions of sodium silicate dosage of 15% of Bentonite, Bentonite and modifier dosage of 1:1, solution pH of 9, temperature of 45 °C and modification time of 5 h, the synthesized sulfhydryl modified Bentonite has good adsorption performance on Ag(?), and its adsorption capacity can reach 293.7 mg·g-1
EnvGuard: Guaranteeing Environment-Centric Safety and Security Properties in Web of Things
Web of Things (WoT) technology facilitates the standardized integration of
IoT devices ubiquitously deployed in daily environments, promoting diverse WoT
applications to automatically sense and regulate the environment. In WoT
environment, heterogeneous applications, user activities, and environment
changes collectively influence device behaviors, posing risks of unexpected
violations of safety and security properties. Existing work on violation
identification primarily focuses on the analysis of automated applications,
lacking consideration of the intricate interactions in the environment.
Moreover, users' intention for violation resolving strategy is much less
investigated. To address these limitations, we introduce EnvGuard, an
environment-centric approach for property customizing, violation identification
and resolution execution in WoT environment. We evaluated EnvGuard in two
typical WoT environments. By conducting user studies and analyzing collected
real-world environment data, we assess the performance of EnvGuard, and
construct a dataset from the collected data to support environment-level
violation identification. The results demonstrate the superiority of EnvGuard
compared to previous state-of-the-art work, and confirm its usability,
feasibility and runtime efficiency
Application of Composite Materials in Engine
This paper analyzes the technical and demand problems of the current automotive and aviation engines, andintroduces the applications of carbon fiber reinforced metal matrix composites and resin matrix composites in thepiston and connecting rods of automobile engines. Composite materials and ceramic matrix composites on civilaircraft engines, as well as composite materials and composites in military aerospace engines (solid rocket motors andtranscendental ramjet) applications, and some of the composite materials The application raises key questions andsuggestions
Kirigami-inspired, highly stretchable micro-supercapacitor patches fabricated by laser conversion and cutting.
The recent developments in material sciences and rational structural designs have advanced the field of compliant and deformable electronics systems. However, many of these systems are limited in either overall stretchability or areal coverage of functional components. Here, we design a construct inspired by Kirigami for highly deformable micro-supercapacitor patches with high areal coverages of electrode and electrolyte materials. These patches can be fabricated in simple and efficient steps by laser-assisted graphitic conversion and cutting. Because the Kirigami cuts significantly increase structural compliance, segments in the patches can buckle, rotate, bend and twist to accommodate large overall deformations with only a small strain (<3%) in active electrode areas. Electrochemical testing results have proved that electrical and electrochemical performances are preserved under large deformation, with less than 2% change in capacitance when the patch is elongated to 382.5% of its initial length. The high design flexibility can enable various types of electrical connections among an array of supercapacitors residing in one patch, by using different Kirigami designs
Balancing Logit Variation for Long-tailed Semantic Segmentation
Semantic segmentation usually suffers from a long-tail data distribution. Due
to the imbalanced number of samples across categories, the features of those
tail classes may get squeezed into a narrow area in the feature space. Towards
a balanced feature distribution, we introduce category-wise variation into the
network predictions in the training phase such that an instance is no longer
projected to a feature point, but a small region instead. Such a perturbation
is highly dependent on the category scale, which appears as assigning smaller
variation to head classes and larger variation to tail classes. In this way, we
manage to close the gap between the feature areas of different categories,
resulting in a more balanced representation. It is noteworthy that the
introduced variation is discarded at the inference stage to facilitate a
confident prediction. Although with an embarrassingly simple implementation,
our method manifests itself in strong generalizability to various datasets and
task settings. Extensive experiments suggest that our plug-in design lends
itself well to a range of state-of-the-art approaches and boosts the
performance on top of them
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