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1.
Chem Commun (Camb) ; 60(15): 2050-2053, 2024 Feb 15.
Article En | MEDLINE | ID: mdl-38288479

We present a novel approach to fabricate endogenous slippery lubricant-infused porous surfaces (eSLIPS) at room temperature using an evaporation-induced phase separation process. The ternary coating system, comprising ethylene-propylene copolymer, caprylyl methicone, and n-hexane, forms a porous structure in situ infiltrated with lubricant, resulting in surfaces with remarkable anti-fouling and anti-icing properties.

2.
Data Brief ; 48: 109291, 2023 Jun.
Article En | MEDLINE | ID: mdl-37383732

Plant factories are an advanced form of facility agriculture that enable efficient plant cultivation through controllable environmental conditions, making them highly suitable for the automation and intelligent application of machinery. Tomato cultivation in plant factories has significant economic and agricultural value and can be utilized for various applications such as seedling cultivation, breeding, and genetic engineering. However, manual completion is still required for operations such as detection, counting, and classification of tomato fruits, and the application of machine detection is currently inefficient. Furthermore, research on the automation of tomato harvesting in plant factory environments is limited due to the lack of a suitable dataset. To address this issue, a tomato fruit dataset was constructed for plant factory environments, named as TomatoPlantfactoryDataset, which can be quickly applied to multiple tasks, including the detection of control systems, harvesting robots, yield estimation, and rapid classification and statistics. This dataset features a micro tomato variety and was captured under different artificial lighting conditions, including changes in tomato fruit, complex lighting environment changes, distance changes, occlusion, and blurring. By facilitating the intelligent application of plant factories and the widespread adoption of tomato planting machinery, this dataset can contribute to the detection of intelligent control systems, operation robots, and fruit maturity and yield estimation. The dataset is publicly available for free and can be utilized for research and communication purposes.

3.
Natl Sci Rev ; 10(7): nwac282, 2023 Jul.
Article En | MEDLINE | ID: mdl-37266561

Relevant to broad applied fields and natural processes, interfacial ionic hydrates have been widely studied by using ultrahigh-resolution atomic force microscopy (AFM). However, the complex relationship between the AFM signal and the investigated system makes it difficult to determine the atomic structure of such a complex system from AFM images alone. Using machine learning, we achieved precise identification of the atomic structures of interfacial water/ionic hydrates based on AFM images, including the position of each atom and the orientations of water molecules. Furthermore, it was found that structure prediction of ionic hydrates can be achieved cost-effectively by transfer learning using neural network trained with easily available interfacial water data. Thus, this work provides an efficient and economical methodology that not only opens up avenues to determine atomic structures of more complex systems from AFM images, but may also help to interpret other scientific studies involving sophisticated experimental results.

4.
Nat Commun ; 14(1): 2955, 2023 May 24.
Article En | MEDLINE | ID: mdl-37225717

The plastic deformation of crystalline materials can be understood by considering their structural defects such as disclinations and dislocations. Although also glasses are solids, their structure resembles closely the one of a liquid and hence the concept of structural defects becomes ill-defined. As a consequence it is very challenging to rationalize on a microscopic level the mechanical properties of glasses close to the yielding point and to relate plastic events to structural properties. Here we investigate the topological characteristics of the eigenvector field of the vibrational excitations of a two-dimensional glass model, notably the geometric arrangement of the topological defects as a function of vibrational frequency. We find that if the system is subjected to a quasistatic shear, the location of the resulting plastic events correlate strongly with the topological defects that have a negative charge. Our results provide thus a direct link between the structure of glasses prior their deformation and the plastic events during deformation.

5.
Sci Rep ; 13(1): 1643, 2023 Jan 30.
Article En | MEDLINE | ID: mdl-36717635

The instability of rock slope is still a very frequent geological disaster, which seriously affects people's life and production activities. Previous studies have mainly focused on deformation mechanism, prediction, and control of hard rock with single lithology, while there are limited studies on the theoretic computational method of the stability for soft-hard interbedded anti-inclined rock strata. In this study, a geomechanical model for the toppling failure of soft-hard-interbedded anti-inclined rock slope is established. The modes of failure for soft and hard rock strata are analyzed, the computational formula of the downward thrust for each anti-inclined rock stratum is derived, and the stability safety factor of each rock stratum is defined. A theoretical computational method for determining the potentially most dangerous failure surface of soft-hard-interbedded anti-inclined rock slope is proposed. By comparing with the existing research results, the theoretical solving method proposed in this study can well solve the location of the potentially most dangerous failure surface of soft-hard-interbedded anti-inclined rock slope. The potentially most dangerous failure surface of this kind of slope is approximately planar, and the angle between it and the normal plane of the rock strata is an acute angle within 30°. It provides theoretical support for the stability analysis of this kind of slope.

6.
Dalton Trans ; 51(22): 8743-8748, 2022 Jun 07.
Article En | MEDLINE | ID: mdl-35612294

Photochemical reactions are vital synthetic means for the synthesis of natural products and highly strained molecules. However, it remains an immense challenge to control the chemo- and regioselectivity in the photoreactions of anthracene derivatives while maintaining high reactivity. Herein, we report the synthesis of two photoactive metallarectangles 1a and 1b by coordination-driven self-assembly of 2,6- and 2,7-bifunctionalized anthracenes with a half-sandwich rhodium template. By taking advantage of the rhodium template, the anthracene groups within the metallarectangles can be preorganized in a parallel fashion and exclusively undergo a photochemical [4 + 4] cycloaddition. As a result, the syn-photodimers were obtained in quantitative yields under irradiation at 365 nm. The photocycloaddition of metallarectangles 1a and 1b was found to be reversible via photo- and thermal cleavage reactions, even after repeating three times. Furthermore, pure organic photodimers 3a and 3b, which are difficult to synthesize by conventional organic methods, can be readily dissociated from the metalloassemblies in high yields.

7.
Nat Commun ; 9(1): 5334, 2018 12 17.
Article En | MEDLINE | ID: mdl-30559382

The dynamics of glass-forming systems shows a multitude of features that are absent in normal liquids, such as non-exponential relaxation and a strong temperature-dependence of the relaxation time. Connecting these dynamic properties to the microscopic structure of the system is challenging because of the presence of the structural disorder. Here we use computer simulations of a metallic glass-former to establish such a connection. By probing the temperature and wave-vector dependence of the intermediate scattering function we find that the relaxation dynamics of the glassy melt is directly related to the local arrangement of icosahedral structures: Isolated icosahedra give rise to a liquid-like stretched exponential relaxation whereas clusters of icosahedra lead to a compressed exponential relaxation that is reminiscent to the one found in a solid. Our results show that in metallic glass-formers these two types of relaxation processes can coexist and give rise to a dynamics that is surprisingly complex.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2134-8, 2016 Jul.
Article Zh | MEDLINE | ID: mdl-30035905

Divertor impurity injection on Tokamak is the most important means to achieve divertor impurity screening efficiency. In this paper, a fast-response extreme-ultraviolet (EUV) spectrometer is used to monitor the Ar emission lines during the EAST(Experimental Advanced Superconducting Tokamak)divertor Ar injection experiment. Based on the NIST(National Institute of Standards and Technology)atomic spectrum database, the emission lines from different ionized Ar ions in 2~50 nm wavelength range, e.g. Ar Ⅳ, Ar Ⅳ-Ⅺ and Ar ⅩⅣ-ⅩⅥ, are being identified. Ar ⅩⅥ 35.39 nm and Ar Ⅳ 44.22 nm with the ionization energy of 918.4 and 59.6 eV respectively are being monitored during the experiment with Ar puffing to observe the behavior of Ar impurities in different regions in plasmasimultaneously. The preliminary analysis on divertor impurity screening efficiency is carried outwith the time evolution of intensities of two Ar emission lines. The results of experiment puffing from the same gas puffing inlet (e. g. from lower outer target inlet) and withdifferent plasma configurations (e. g. lower single null, upper single null) show that the screening effect on the impurity injected from the divertor region is better thanfrom the main plasma region; the screening effect of lower divertor and particle pumping by internal cryopump installed in lower divertor is stronger than upper divertor.

9.
Bioorg Med Chem Lett ; 23(23): 6421-6, 2013 Dec 01.
Article En | MEDLINE | ID: mdl-24120543

In the present study, andrographolide (Andro, 1) derivatives were screened to identify potent inhibitors against tumor-cell migration and invasion, and associated structure-activity relationships were studied. Compared to 1, compounds 8a-8d exhibited more potent activities against migration in SGC-7901, PC-3, A549, HT-29 and Ec109 cell lines. Improved activities against tumor-cell migration and invasion were proved to be associated with the down-regulation of MMPs.


Cell Movement/drug effects , Diterpenes/chemistry , Diterpenes/pharmacology , Neoplasms/drug therapy , Cell Proliferation/drug effects , Diterpenes/chemical synthesis , Drug Screening Assays, Antitumor , HT29 Cells , Humans , Neoplasms/pathology , Structure-Activity Relationship
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(1): 119-23, 2005 Jan.
Article Zh | MEDLINE | ID: mdl-15852835

The main efforts of HT-7 superconducting tokamak were directed to quasi-steady state discharges and their relevant physics. Significant progress in obtaning high-performance discharges under quasi-steady state in HT-7 has been realized. The long pulse discharges have been obtained with a duration up to 63.95 s. The edge recycling was studied by the ratio of H to D through OSMA (Optical Spectroscopy Multichannel Analyzer) system. During the discharge, recycling dominated the particle balance. In the steady state, when the density was controllable, the deuterium(hydrogen) recycling played an important role and the recycling coefficient R < or = 1. During the later time, R >1 and the density was uncontrollable. The main contribution was from the D(H) recycling and impurity from the surfaces of the limiter and the first wall due to the increased surface temperature and radiation power, and these limited the duration of long duration discharges. The influence of wall conditioning on the edge recycling was also studied through the ratio of H to D.


Deuterium/chemistry , Hydrogen/chemistry , Spectrum Analysis/instrumentation , Spectrum Analysis/methods , Algorithms , Kinetics , Models, Chemical , Optics and Photonics
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