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771.
Intrinsic viscosity and critical concentration of sago starch dispersions were studied at different temperatures and presence of solutes (sodium chloride, glucose and sucrose). Ubbelohde capillary viscometer was used to measure relative viscosity. Intrinsic viscosity decreases with an increase in temperature but the critical concentration remained fairly constant over the range of temperature studied. Sodium chloride enhanced the intrinsic viscosity but sugars somehow reduced it. Critical concentration is defined as the point where the starch molecules start to entangle with each other and abruptly enhance viscosity. Sodium chloride enhanced the molecular entanglement and lowered the critical concentration. 相似文献
772.
Noor Abu Jarad Kenneth Rachwalski Fereshteh Bayat Shadman Khan Amid Shakeri Roderick MacLachlan Martin Villegas Eric D. Brown Leyla Soleymani Tohid F. Didar 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(12):2205761
Engineered surfaces that repel pathogens are of great interest due to their role in mitigating the spread of infectious diseases. A robust, universal, and scalable omniphobic spray coating with excellent repellency against water, oil, and pathogens is presented. The coating is substrate-independent and relies on hierarchically structured polydimethylsiloxane (PDMS) microparticles, decorated with gold nanoparticles (AuNPs). Wettability studies reveal the relationship between surface texturing of micro- and/or nano-hierarchical structures and the omniphobicity of the coating. Studies of pathogen transfer with bacteria and viruses reveal that an uncoated contaminated glove transfers pathogens to >50 subsequent surfaces, while a coated glove picks up 104 (over 99.99%) less pathogens upon first contact and transfers zero pathogens after the second touch. The developed coating also provides excellent stability under harsh conditions. The remarkable anti-pathogen properties of this surface combined with its ease of implementation, substantiate its use for the prevention of surface-mediated transmission of pathogens. 相似文献
773.
For fuzzy systems to be implemented effectively, the fuzzy membership function (MF) is essential. A fuzzy system (FS) that implements precise input and output MFs is presented to enhance the performance and accuracy of single-input single-output (SISO) FSs and introduce the most applicable input and output MFs protocol to linearize the fuzzy system’s output. Utilizing a variety of non-linear techniques, a SISO FS is simulated. The results of FS experiments conducted in comparable conditions are then compared. The simulated results and the results of the experimental setup agree fairly well. The findings of the suggested model demonstrate that the relative error is abated to a sufficient range (≤ ± 10%) and that the mean absolute percentage error (MPAE) is reduced by around 66.2%. The proposed strategy to reduce MAPE using an FS improves the system’s performance and control accuracy. By using the best input and output MFs protocol, the energy and financial efficiency of every SISO FS can be improved with very little tuning of MFs. The proposed fuzzy system performed far better than other modern days approaches available in the literature. 相似文献
774.
Silicon - This work aims to improve the structural, optical and electrical characteristics of silicon carbide(SiC) yttrium oxide(Y2O3) nanostructures doped poly-methyl methacrylate(PMMA) to utilize... 相似文献
775.
With the development of deep learning, numerous models have been proposed for human activity recognition to achieve state-of-the-art recognition on wearable sensor data. Despite the improved accuracy achieved by previous deep learning models, activity recognition remains a challenge. This challenge is often attributed to the complexity of some specific activity patterns. Existing deep learning models proposed to address this have often recorded high overall recognition accuracy, while low recall and precision are often recorded on some individual activities due to the complexity of their patterns. Some existing models that have focused on tackling these issues are always bulky and complex. Since most embedded systems have resource constraints in terms of their processor, memory and battery capacity, it is paramount to propose efficient lightweight activity recognition models that require limited resources consumption, and still capable of achieving state-of-the-art recognition of activities, with high individual recall and precision. This research proposes a high performance, low footprint deep learning model with a squeeze and excitation block to address this challenge. The squeeze and excitation block consist of a global average-pooling layer and two fully connected layers, which were placed to extract the flattened features in the model, with best-fit reduction ratios in the squeeze and excitation block. The squeeze and excitation block served as channel-wise attention, which adjusted the weight of each channel to build more robust representations, which enabled our network to become more responsive to essential features while suppressing less important ones. By using the best-fit reduction ratio in the squeeze and excitation block, the parameters of the fully connected layer were reduced, which helped the model increase responsiveness to essential features. Experiments on three publicly available datasets (PAMAP2, WISDM, and UCI-HAR) showed that the proposed model outperformed existing state-of-the-art with fewer parameters and increased the recall and precision of some individual activities compared to the baseline, and the existing models. 相似文献
776.
Arif Hussain Haiyang Yan Noor Ul Afsar Chenxiao Jiang Yaoming Wang Tongwen Xu 《Frontiers of Chemical Science and Engineering》2022,16(5):764
Bipolar membrane electrodialysis (BMED) is considered a state-of-the-art technology for the conversion of salts into acids and bases. However, the low concentration of base generated from a traditional BMED process may limit the viability of this technology for a large-scale application. Herein, we report an especially designed multistage-batch (two/three-stage-batch) BMED process to increase the base concentration by adjusting different volume ratios in the acid (Vacid), base (Vbase), and salt compartments (Vsalt). The findings indicated that performance of the two-stage-batch with a volume ratio of Vacid:Vbase:Vsalt = 1:1:5 was superior in comparison to the three-stage-batch with a volume ratio of Vacid:Vbase:Vsalt = 1:1:2. Besides, the base concentration could be further increased by exchanging the acid produced in the acid compartment with fresh water in the second stage-batch process. With the two-stage-batch BMED, the maximum concentration of the base can be obtained up to 3.40 mol∙L–1, which was higher than the most reported base production by BMED. The low energy consumption and high current efficiency further authenticate that the designed process is reliable, cost-effective, and more productive to convert saline water into valuable industrial commodities. 相似文献
777.
Lamiya Noor Atolo Tuinukuafe Jason H. Ideker 《Journal of the American Ceramic Society》2023,106(6):3303-3328
Ettringite-accelerated binders composed of CAC–PC–C$ (calcium aluminate cement–Portland cement–calcium sulfate) and CSA–PC–C$ (calcium sulfoaluminate cement–Portland cement–calcium sulfate) have been used widely for indoor applications, such as self-leveling floor screeds, underlayment, and tile adhesives owing to their rapid setting, early strength gain, and shrinkage compensation properties. These properties also make these binders appealing candidates for outdoor rapid repair (e.g., highways, bridge decks, and airfield pavements). However, a central question remains: Does ettringite remain stable in outdoor exposure conditions? If so, which factors will contribute positively/negatively to the long-term stability of ettringite in these systems? To address these questions, this critical review presents the current state of knowledge regarding the hydration of ternary binders composed of CAC–PC–C$ and CSA–PC–C$ with respect to ettringite formation and the factors affecting the stability of ettringite thereafter. The purpose of this review paper is to synthesize and analyze current research regarding conditions that promote or deter ettringite stability, establish what information is missing, unclear, or contradictory, and identify remaining research needs to address the identified knowledge gaps. 相似文献
778.
Residual native starch was extracted from sago pith residue using two types of commercial cell‐wall degrading enzymes, Pectinex Ultra SP‐L and Ultrazyme 100G. The first increased starch yield with a shorter incubation period than the second. The superior effect of Pectinex Ultra SP‐L was observed already at 0.5 h, where a wide granule size distribution (8—87 μm) was obtained. A slight increase in the release of granules ranging from 30—60 μm was noted within a 2 h incubation period. However, upon further incubation, the distribution pattern was similar to that of untreated samples. Samples treated with Ultrazyme 100G exhibited a unimodal distribution pattern, with larger granules, ranging from 40—70 μm, being released upon further incubation within a 2 h incubation period. However, all samples exhibited a bimodal distribution upon further incubation. 相似文献
779.
Nawawi Nur Izzati Mohamed Ijod Giroon Senevirathna Sri Sampath Janaka Aadil Rana Muhammad Yusof Noor Liyana Yusoff Masni Mat Adzahan Noranizan Mohd Azman Ezzat Mohamad 《Food science and biotechnology》2023,32(6):729-747
Food Science and Biotechnology - Strawberry (Fragaria ananassa) is rich in bioactive compounds with high antioxidant activity. High pressure processing (HPP) is an efficient alternative to preserve... 相似文献
780.
Xin Hu Rujun Yu Faming Wang Zunfeng Liu Hongyu Yang Chaoji Chen Yangling Li Nuruzzaman Noor Bin Fei 《Advanced functional materials》2023,33(37):2303278
Transparent wood (TW)-based materials have increasingly become the focus of researchers worldwide owing to their superior physico-chemical-optical properties, sustainable nature, as well as the fact that they are highly accommodating frameworks that can act as building blocks to readily explore a vast range of potential functionalities, holding great potential to displace glass and plastics in their various respective applications. The integration of multiple functionalities into TW has been undertaken to fulfill the demands of prospective sophisticated applications through the utilization of functional fillers or coatings. Herein, the up-to-date foundational developments and reports concerning emergent TW composites and coatings from a perspective of fabrication-functionality-application are comprehensively summarized, with a particular focus on seven specific functionalities; i) solar control; ii) chromically-responsive, iii) electrically-conductive, iv) shape-memory active; v) flame-retardant; vi) electromagnetic interference shielding; and vii) aesthetics. The potential applications of TW with these functionalities are also discussed. Finally, the current challenge with TW is addressed, as well as the future developments required for eventual real-world application. 相似文献