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1.
Zheng Z Ahmed N Mueller K 《IEEE transactions on visualization and computer graphics》2011,17(12):1959-1968
The unguided visual exploration of volumetric data can be both a challenging and a time-consuming undertaking. Identifying a set of favorable vantage points at which to start exploratory expeditions can greatly reduce this effort and can also ensure that no important structures are being missed. Recent research efforts have focused on entropy-based viewpoint selection criteria that depend on scalar values describing the structures of interest. In contrast, we propose a viewpoint suggestion pipeline that is based on feature-clustering in high-dimensional space. We use gradient/normal variation as a metric to identify interesting local events and then cluster these via k-means to detect important salient composite features. Next, we compute the maximum possible exposure of these composite feature for different viewpoints and calculate a 2D entropy map parameterized in longitude and latitude to point out promising view orientations. Superimposed onto an interactive track-ball interface, users can then directly use this entropy map to quickly navigate to potentially interesting viewpoints where visibility-based transfer functions can be employed to generate volume renderings that minimize occlusions. To give full exploration freedom to the user, the entropy map is updated on the fly whenever a view has been selected, pointing to new and promising but so far unseen view directions. Alternatively, our system can also use a set-cover optimization algorithm to provide a minimal set of views needed to observe all features. The views so generated could then be saved into a list for further inspection or into a gallery for a summary presentation. 相似文献
2.
Yandi Luo Guojie Chen Shuo Chen Nafees Ahmad Muhammad Azam Zhuanghao Zheng Zhenghua Su Michel Cathelinaud Hongli Ma Zhigang Chen Ping Fan Xianghua Zhang Guangxing Liang 《Advanced functional materials》2023,33(14):2213941
Exhibiting outstanding optoelectronic properties, antimony selenide (Sb2Se3) has attracted considerable interest and has been developed as a light absorber layer for thin-film solar cells over the decade. However, current state-of-the-art Sb2Se3 devices suffer from unsatisfactory “cliff-like” band alignment and severe interface recombination loss, which deteriorates device performance. In this study, the heterojunction interface of an Sb2Se3 solar cell is improved by introducing effective aluminum (Al3+) cation into the CdS buffer layer. Then, the energy band alignment of Sb2Se3/CdS:Al heterojunction is modified from a “cliff-like” structure to a “spike-like” structure. Finally, heterojunction interface engineering suppresses recombination losses and strengthens carrier transport, resulting in a high efficiency of 8.41% for the substrate-structured Sb2Se3 solar cell. This study proposes a facile strategy for interfacial treatment and elucidates the related carrier transport enhancement mechanism, paving a bright avenue to overcome the efficiency bottleneck of Sb2Se3 thin-film solar cells. 相似文献
3.
In this effort, series of polyvinyl chloride (PVC) and 4-aminobenzoic acid (4ABA)-modified PVC and functional graphite (FG)-based membranes were prepared. Fourier transform infrared spectroscopy and X-ray diffraction analysis were used to confirm PVC and graphite modification and nanocomposite formation. Scanning electron microscopy depicted homogenously layered morphology of modified PVC nanocomposite. Glass-transition temperature (Tg) of non-modified PVC nanocomposite was 243°C, whereas modified nanocomposite with similar FG loading had Tg of 258°C. Higher filler content furnished better hydrophilic membranes. Efficiency of PVC–4ABA-0.5/FG 0.5 membrane was 100% for removal of Hg2+ and Pb2+. PVC–4ABA-0.5/FG 0.5 membrane with smaller contact angle (30°) is a fine option for water purification. 相似文献
4.
Bukhari Muhammad Adnan Ahmad Zahoor Ashraf M. Yasin Afzal Muhammad Nawaz Fahim Nafees Muhammad Jatoi Wajid Nasim Malghani Naveed Aslam Shah Adnan Noor Manan Abdul 《SILICON》2021,13(12):4757-4772
Silicon - Feeling prone to stress differs with plant production stage, water scarcity near commencement of grain filling phase has a significant reduced grain yield through fewer endosperm and sink... 相似文献
5.
This review mainly concentrates on polyvinyl chloride/carbon nanofiller-based composites. The present study focused upon synthetic strategies and relevance of polyvinyl chloride/graphite, polyvinyl chloride/graphene, polyvinyl chloride/graphene oxide, and polyvinyl chloride/carbon nanotube nanocomposite. Among carbon-based reinforcement, graphene oxide nanofiller depicted better dispersion in polyvinyl chloride matrix. The electrical, mechanical, thermal, and morphological properties of these nanocomposites are also discussed. Moreover, future potential of these materials are elucidated. There is relatively little literature available regarding polyvinyl chloride-based nanocomposite. The main aim of this article is to therefore particularize the polyvinyl chloride-based nanocomposites and expose their concealed properties to enable better use of these new materials in different technical fields. 相似文献
6.
Mostafa Ali Mosalam Sabrnal H. El Hamouly Amaal Ahemad Mahmoud Ahemad Abdel Salam Khalil 《Journal of Polymer Research》2011,18(6):2141-2150
8-methacryloxy-quinoline monomer (MAQ) was prepared by the reaction of 8-hydroxyquinoline with either methacryloyl chloride or methacrylic acid in the presence of triethylamine and N, N′-dicyclohexylcarbodiimide, respectively. Its structure was confirmed by IR and 1 H-NMR spectroscopy. Binary copolymerization of this new monomer with methyl acrylate (MA), acrylonitrile (AN) methyl methacrylate (MMA), styrene(ST), were performed in Dimethylformamide, using 1 mol% azobisisobutyronitrile as initiator at 65 °C. The copolymer compositions were determined from nitrogen analysis except MAQ-AN with 1 H-NMR. Copolymerization Parameters for each system were calculated by both the Finemen-Ross and Kelen-Tüdös methods. The monomer reactivity ratios for the systems MAQ-MA, MAQ-AN, MAQ-MMA and MAQ-ST were found to be r1?=?0.695?±?0.036, r2?=?0.62?±?0.235; r1?=?0.273?±?0.087, r2?=?0.259?±?0.67; r1?=?0.356?±?0.015, r2?=?1.615?±?0.052 and r1?=?0.097?±?0.003, r2?=?0.339?±?0.027 respectively. The Q and e values for MAQ monomer were found to be 1.62 and 1.40. 相似文献
7.
Sami Ullah Sara Ali Afroz Binte Abid Muhammad Nafees 《Microscopy research and technique》2022,85(3):1135-1145
Nanotechnology has been amplified in different areas of science as well as agriculture in the present era. So, the present work was designed to evaluate the result of nitrate mediated silver nanoparticles (Nit-AgNPs) and indole acetic acid (IAA) on physio-biochemical features of the selected maize variety (Pahari white) under 40 and 80 mM salinity induction. Seeds were propagated in triplicates in earthen pots (18 cm inferior and superior inside diameter, 20 cm stature, and 2 cm breadth) filled with silt and soil (1:2) having 3.09–5.12 Electrical conductivity (EC), 6.8–7.3 pH, and 4–16% moisture contents. Scanning electron microscopy results showed the average particle size around 90 nm indicating a high surface area suitable for adsorption properties, agglomerated, roughly spherical, and were uniformly dispersed. Elemental quantification of biosynthesized AgNPs analyzed via energy dispersive X-ray spectroscopy showed a strong peak at 3.0 KeV along with the presence of elements K, N, O, and C. Results of Thermo-gravimetric Analysis (TGA)/Differential Thermal Analysis (DTA) showed endothermic major decline at 150–300°C, while exothermic peak at 300–400°C. The growth responses at 40 mM salinity concentration have been reduced representing from the least boundary of chlorophyll “a,” “b,” and peroxidase content, whereas; this adverse effect has been reduced by operation of Nit-AgNPs as separate treatment and in combination with IAA. From the current study, it has been concluded that salinity concentration at 80 mM adversely affected the values of osmolytes, protein, and superoxide dismutase whereas the maximum amplitude of proline reduced by the application of Nit-AgNPs as distinct treatment indicating that the plant behaves normal with the combined application of nanoparticles and IAA. 相似文献
8.
Sikander Afzal Dheeraj Ajay Chatterjee Abhi Ahamad Nafees 《Microsystem Technologies》2022,28(12):2821-2828
Microsystem Technologies - Nowadays, microgrid energy storage system is in great demand in order to compensate the demand-generation mismatch. In this study a new control design strategy is... 相似文献
9.
Heavy metal pollution of river water has health implications. This study was aimed to test if bacteria that are heavy metal resistant can resist antibiotics. Heavy metal-resistant bacteria were isolated using Nutrient agar plates amended with 100?μg?ml?1 of metal salts. Isolates were further screened to determine minimal inhibitory concentration against each metal. The isolates belonged to the genera of Neisseria, Bacillus, Pseudomonas, Staphylococcus, Streptococcus, Micrococcus, Corynebacterium and Proteus. Minimum inhibitory concentration of the isolates for heavy metals ranged from 200 to 2300?μg?ml?1. Isolates of Pseudomonas, Neisseria, Bacillus, Protues, Streptococcus, Staphylococcus and Micrococcus spp. exhibited multiple antibiotic resistance. Statistically significant correlation between metal resistance and antibiotic resistance was observed among bacterial isolates. The present work suggests that some of the isolates could be hazardous to human beings as a result of natural selection of dual resistant mechanisms. 相似文献
10.
Saima Sultana Nafees Ahmad Syed M. Faisal M. Owais Suhail Sabir 《IET nanobiotechnology / IET》2017,11(7):835
Biodegradable polymers have greatly promoted the development of environmental, biomedical and allied sciences because of their biocompatibility and doping chemistry. The emergence of nanotechnology has envisaged greater options for the development of biodegradable materials. Polyaniline grafted chitosan (i.e. biodegradable PANI) copolymer was prepared by the chemical in situ polymerisation of aniline using ammonium per sulphate as initiator while Ag nanoparticle were synthesised by chemical reduction method and incorporated in to the polymer matrix. The as prepared materials were characterised by X‐ray diffraction, Fourier transform Infra‐red spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis. Moreover energy storage capacity, impedance properties were also studied. The main focus was on the photocatalytic degradation of organic dyes to remove the toxic and carcinogenic pollutants. This polymer nano‐biocomposite has multifold applications and can be used as excellent materials for enhanced photodegradation and removal of toxic contaminants from waste waters and natural water streams. In addition, the biocompatible materials with excellent mechanical properties and low toxicity can also be used for tissue engineering, drug delivery and electrical energy storage devices.Inspec keywords: silver, filled polymers, polymer blends, nanocomposites, nanoparticles, nanofabrication, biodegradable materials, polymerisation, reduction (chemical), Fourier transform infrared spectra, transmission electron microscopy, X‐ray chemical analysis, X‐ray diffractionOther keywords: polyaniline‐chitosan‐silver‐nanobiocomposite, biodegradable polymers, biocompatibility, doping chemistry, nanotechnology, biodegradable PANI, polyaniline grafted chitosan copolymer, biodegradable materials, chemical in situ polymerisation, nanoparticle, polymer matrix, chemical reduction method, Fourier transform Infrared spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis, X‐ray diffraction, energy storage capacity, impedance properties, carcinogenic pollutants, toxic pollutants, photodegradation, toxic contaminants, natural water streams, waste waters, drug delivery, tissue engineering, electrical energy storage devices, mechanical properties, Ag 相似文献