Conventional polymer membranes suffer from low flux and serious fouling when used for treating emulsified oil/water mixtures. Reported herein is the fabrication of a novel superhydrophilic and ...underwater superoleophobic poly(acrylic acid)‐grafted PVDF filtration membrane using a salt‐induced phase‐inversion approach. A hierarchical micro/nanoscale structure is constructed on the membrane surface and endows it with a superhydrophilic/underwater superoleophobic property. The membrane separates both surfactant‐free and surfactant‐stabilized oil‐in‐water emulsions under either a small applied pressure (<0.3 bar) or gravity, with high separation efficiency and high flux, which is one to two orders of magnitude higher than those of commercial filtration membranes having a similar permeation property. The membrane exhibits an excellent antifouling property and is easily recycled for long‐term use. The outstanding performance of the membrane and the efficient, energy and cost‐effective preparation process highlight its potential for practical applications.
Salting away: The title membranes having different PAA graft ratios were fabricated by using a salt‐induced phase‐inversion process. The membrane can separate both surfactant‐free and surfactant‐stabilized oil‐in‐water emulsions under either a small applied pressure (0.1 bar) or gravity, with a high separation efficiency and high flux. CA=contact angle.
As an alternative to polymer membranes, ultrathin free‐standing single‐walled carbon‐nanotube network films are used to realize oil/water separation with ultrahigh flux. The films with tunable ...thickness of the tens of nanometer scale can effectively separate both micrometer and nanometer‐sized surfactant‐free and surfactant‐stabilized water‐in‐oil emulsions with a flux 2–3 orders of magnitude higher than commercial filtration membranes with similar separation performance.
In this paper, we present an open-source multi-resolution and multi-physics library, SPHinXsys, which is released under the Apache License (2.0). Along with the source code, a complete documentation ...is also distributed for easy compilation and execution. SPHinXsys aims at modeling coupled multi-physics industrial dynamic systems within a unified SPH framework. It has two important features, namely, (1) the generic design providing a C++ API with very good flexibility for domain-specific applications, (2) the unified framework within which numerous industrial or scientific applications can be coupled. The present version (v0.2.0) includes a wide range of validation tests and applications in the fields of fluid dynamics, solid dynamics, thermal and mass diffusion, reaction-diffusion, electromechanics and fluid-structure interactions.
Program Title: SPHinXsys
CPC Library link to program files:https://doi.org/10.17632/9rh6hyd89n.1
Developer's repository link:https://github.com/Xiangyu-Hu/SPHinXsys
Code Ocean capsule:https://doi.org/10.24433/CO.0560985.v1
Licensing provisions: Apache-2.0
Programming language: C++
External dependencies: cmake, Boost, Threading Building Blocks (TBB), SimBody
Nature of problem:: Multi-physics problems are ubiquitous in natural phenomena and play key roles in a vast range of scientific and industrial applications. Typical examples include aerial animal flying, aquatic animal swimming and the flow of blood in the heart and throughout the cardiovascular system. Due to the inter-discipline characteristics and intrinsic complexities, computational modeling of multi-physics problems is highly challenging.
Solution method:: An open-source library is proposed for solving multi-physics problems in a unified multi-resolution Smoothed Particle Hydrodynamics framework. In particular, the library is applied for modeling cardiac functions where critical aspects of electrophysiology, passive and active mechanical responses are involved.
Robotic welding often uses vision-based measurement to find the correct placement of the welding seam. Traditional machine vision methods work well in many cases but lack robustness when faced with ...variations in the manufacturing process or in the imaging conditions. While supervised deep neural networks have been successful in increasing accuracy and robustness in many real-world measurement applications, their success relies on labeled data. In this paper, we employ semi-supervised learning to simultaneously increase accuracy and robustness while avoiding expensive and time-consuming labeling efforts by a domain expert. While semi-supervised learning approaches for various image classification tasks exist, we purpose a novel algorithm for semi-supervised key-point detection for seam placement by a welding robot. We demonstrate that our approach can work robustly with as few as fifteen labeled images. In addition, our method utilizes full image resolution to enhance the accuracy of the key-point detection in seam placement.
Realization of electromagnetic energy confinement beyond the diffraction limit is crucial for high-performance on-chip devices. Herein we construct an array of nonradiative anapoles that originate ...from the destructive far-field interference of electric and toroidal dipole modes to achieve ultracompact and high-efficiency electromagnetic energy transfer without the coupler. We experimentally investigate the proposed metachain at mid-infrared frequencies and give the first near-field experimental evidence of anapole-based energy transfer, in which the spatial profile of the anapole mode is also unambiguously identified on the nanoscale. We further demonstrate that the metachain is intrinsically lossless and scalable at infrared wavelengths, realizing a 90° bending loss down to 0.32 dB at the optical communication wavelength. The present scheme bridges the gap between the energy confinement and the transfer of anapoles and opens a new gate for more compactly integrated photonic and energy devices, which can operate in a broad spectral range.
Food safety has long been the subject of scholarly research, and street food is a weak link in food safety supervision. Street food not only provides convenience for many people, but is also the ...livelihood for millions of low income people, making a great contribution to the economy of many developing countries.
Street food safety is essential, and yet it has been rarely studied in China. Therefore, a typical city in China was selected as the research object to assess food safety knowledge, attitudes, and street food suppliers and consumer behaviors using questionnaires based on previous studies, and considering China's particular characteristics and reasonable impacts identified in previous studies, such as increased income, work experience, licenses, and locations. The food safety knowledge and attitude questionnaire conformed with the national conditions in China. It was used to assess the food safety knowledge and attitudes toward food suppliers and consumers, where three main areas were addressed in the surveys and statistical analysis, as follows. (1) Statistical information including gender, age, education, income, food safety training, and specific elements related to the work experience of suppliers. (2) Knowledge of food safety including the awareness of consumers and suppliers regarding food poisoning pathogens, food and personal hygiene, high-risk groups, and correct cleaning. (3) A list of food handling behaviors was used to determine the behaviors and characteristics of subjects.
The results show that street food suppliers have generally poor food handling practices, and most are operating under unsanitary conditions. Food safety knowledge of street vendors in the High-tech Industries Development Zone was the lowest, most likely because these regions are located in rural-urban fringe zones, where education levels are generally relatively low. Food safety attitudes of the youngest consumers were significantly better than those of older age groups. Their educational level was also different, with correspondingly relatively high income for younger individuals. Most vendors chose locations near schools or supermarkets. Consumers and street food vendors had good understanding of food safety, but street vendors were relatively poor in carrying out safe food handling, with only 26.7% using or being fully equipped withhand-washing facilities, although more than 60% of vendors wore clean and tidy clothes and masks.
Street food vendor training should be prioritized to improve the safety of street food. Other policies and measures should also be propagated to improve the food safety knowledge, attitudes, and behavior of vendors in Handan. Steps should be taken to improve street food stall operating conditions and facilities, including providing clean protected structures, access to potable water, and efficient waste collection and disposal systems. These findings should encourage government agencies to further promote strategies to improve street food safety.
High levels of ultrafine particles (UFPs; diameter of less than 50 nm) are frequently produced from new particle formation under urban conditions, with profound implications on human health, weather, ...and climate. However, the fundamental mechanisms of new particle formation remain elusive, and few experimental studies have realistically replicated the relevant atmospheric conditions. Previous experimental studies simulated oxidation of one compound or a mixture of a few compounds, and extrapolation of the laboratory results to chemically complex air was uncertain. Here, we show striking formation of UFPs in urban air from combining ambient and chamber measurements. By capturing the ambient conditions (i.e., temperature, relative humidity, sunlight, and the types and abundances of chemical species), we elucidate the roles of existing particles, photochemistry, and synergy of multipollutants in new particle formation. Aerosol nucleation in urban air is limited by existing particles but negligibly by nitrogen oxides. Photooxidation of vehicular exhaust yields abundant precursors, and organics, rather than sulfuric acid or base species, dominate formation of UFPs under urban conditions. Recognition of this source of UFPs is essential to assessing their impacts and developing mitigation policies. Our results imply that reduction of primary particles or removal of existing particles without simultaneously limiting organics from automobile emissions is ineffective and can even exacerbate this problem.
Buildings with shallow foundation are vulnerable to liquefaction-induced settlement during an earthquake. Accurate settlement evaluation is an important step in earthquake damage mitigation. This ...paper presents a simplified approach to estimate the liquefaction-induced settlement of buildings with shallow foundations. The multivariate adaptive regression splines (MARS) algorithm is adopted. The validated finite difference method is used to produce artificial data that consider various properties of the soils, structures and ground motions. A relative importance analysis is conducted to quantify the effect of each input parameter and their coupled interactions on the liquefaction-induced settlement. The accuracy of the established model is demonstrated through centrifuge test results available in the literature.
•A MARS model is developed to predict the liquefaction-induced settlement of shallow foundations.•The relationship between a series of affecting factors and the liquefaction-induced settlements is described.•The influences of affecting factors on the liquefaction-induced settlements have been quantitatively analysed.•The accuracy and precision of the developed MARS model are validated using collected centrifuge tests in prior literatures.
Chemo-PTT, which combines chemotherapy with photothermal therapy, offers a viable approach for the complete tumor eradication but would likely fail in drug-resistant situations if conventional ...chemotherapeutic agents are used. Here we show that a type of copper (Cu)-palladium (Pd) alloy tetrapod nanoparticles (TNP-1) presents an ideal solution to the chemo-PTT challenges. TNP-1 exhibit superior near-infrared photothermal conversion efficiency, thanks to their special sharp-tip structure, and induce pro-survival autophagy in a shape- and composition-dependent manner. Inhibition of autophagy with 3-methyl adenine or chloroquine has a remarkable synergistic effect on TNP-1-mediated PTT in triple-negative (4T1), drug-resistant (MCF7/MDR) and patient-derived breast cancer models, achieving a level of efficacy unattainable with TNP-2, the identically-shaped CuPd nanoparticles that have a higher photothermal conversion efficiency but no autophagy-inducing activity. Our results provide a proof-of-concept for a chemo-PTT strategy, which utilizes autophagy inhibitors instead of traditional chemotherapeutic agents and is particularly useful for eradicating drug-resistant cancer.
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