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41.
Dye‐affinity adsorption is increasingly used for protein separation. Hollow‐fibres have advantages as adsorbents in comparison to conventional bead supports because they are not compressible and can eliminate internal diffusion limitations. The aim of this study was to explore in detail the performance of polyamide hollow‐fibres to which Reactive Green HE‐4BD was attached for adsorption of lysozyme. The hollow‐fibre was characterized by scanning electron microscopy. These dye‐carrying hollow‐fibres (26.3 µmol g?1) were used in the lysozyme adsorption–elution studies. The effect of initial concentration of lysozyme and medium pH on the adsorption efficiency of dye‐attached hollow‐fibres was studied in a batch system. The non‐specific adsorption of lysozyme on the polyamide hollow‐fibres was 1.8 mg g?1. Reactive Green HE‐4BD attachment significantly increased the lysozyme adsorption up to 41.1 mg g?1. Langmuir adsorption model was found to be applicable in interpreting lead adsorption by Reactive Green HE‐4BD attached hollow fibres. Significant amount of the adsorbed lysozyme (up to 95%) was eluted in 1 h in the elution medium containing 1.0 M NaSCN at pH 8.0. In order to determine the effects of adsorption conditions on possible conformational changes of lysozyme structure, fluorescence spectrophotometry was employed. We concluded that polyamide dye‐affinity hollow‐fibres can be applied for lysozyme adsorption without causing any significant conformational changes. Repeated adsorption–elution processes showed that these dye‐attached hollow‐fibres are suitable for lysozyme adsorption. © 2001 Society of Chemical Industry 相似文献
42.
The weather in Baghdad, Iraq is hot dry in the summer while water is plentiful and cheap. These are conditions which encourage the use of evaporative cooling. A building with one space in it was used to test the effect of a roof pond which was ventilated mechanically for summer cooling. Thermal measurements were taken for the room in normal conditions without a pond, with a lone pond and no mechanical ventilation, and then finally with mechanically forced ventilation. The results showed a marked improvement in the space temperature with a significant reduction during the peak time outside temperatures at 3 O’clock reaching 6.0 °C between the room without the pond and with a ventilated one and 6.5° at 18:00 during peak inside temperatures. The study also showed that improvements would be better in real-life conditions where exterior wall area is less than the test room. 相似文献
43.
N. P. Bharathi Nazia Umar Khan Sheikh Shreaz Athar Adil Hashmi 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(4):558-565
Zinc containing oil based polyesteramide resins were synthesized by condensation polymerization reaction between castor/soyabean
oil derived castor/soyabean fatty amide diol (HECA/HESA), Zn (OH)2 and adipic acid. The conventional spectroscopic techniques such as FTIR, 1HNMR, 13CNMR have been used to establish the structure of the polymers. Standard laboratory methods were used to study the physicochemical
characteristics like acid value, hydroxyl value, saponification value, iodine value, specific gravity, and viscosity. The
thermal behaviour of the polymers was analyzed by using thermo gravimetric analysis (TGA) and differential scanning calorimetry
(DSC). In vitro antifungal (anticandidial) activity of the polymers was studied against C. albicans ATCC-10261, C. glabrata ATCC-90030 and C. tropicalis ATCC-750, respectively. Antibacterial activity against Gram positive (S. subtillis) and Gram negative bacteria (E. coli and S. typhi) was also examined. For more accuracy, growth curve studies were carried out with the polymer SZ showing higher biological
activity against E. coli by using conventional spectrophotometer. The result showed that the polymers have potent anticandidial and antibacterial
activities. 相似文献
44.
45.
Effects of Guar–Xanthan Gum Mixture as Fat Replacer on the Physicochemical Properties and Oxidative Stability of Goshtaba,a Traditional Indian Meat Product 下载免费PDF全文
46.
47.
Nadia Chlibi José P.B. Silva Eliana M.F. Vieira Luís M. Goncalves Joaquim Agostinho Moreira Adil Chahboun Hassen Dahman Mário Pereira Maria J.M. Gomes Lassaad El Mir 《Ceramics International》2021,47(16):22594-22603
Spin-coated chalcostibite CuSbS2 thin films (≈500 nm thick) were fabricated and the influence of the drying temperature on the structural, morphological, optical and thermoelectric properties of the films was investigated. Crystalline phase-pure chalcostibite has been obtained for the films dried at 180 °C and 210 °C, while below 180 °C these films are partially amorphous. Surprisingly, at drying temperature of 240 °C, a CuxS secondary phase appeared. The increase of the drying temperature leads to the increase of the particle size and the decrease of the optical band gap, which is interesting for optoelectronic applications. The highest power factor value was achieved for the film dried at 210 °C, due to the inexistence of secondary phases, which allowed realizing a stable thermoelectric touch sensor with a Vsignal/noise of 5. In addition, this film was tested as a photovoltaic (PV) device and a power conversion efficiency (PCE) of 0.030% with an open-circuit voltage (VOC) of 0.36 V, a short-circuit current density (JSC) of 0.278 mAcm?2 and a fill factor (FF) of 0.27 were obtained. Therefore, this work evidences a pathway toward developing bi-functional devices with simultaneously thermoelectric touch sensor and photovoltaic functions. 相似文献
48.
Shaikh Adil Atanu H Jana Bhavbhuti M Mehta V B Darji 《International Journal of Dairy Technology》2023,76(2):371-380
Frozen yoghurt rich in β-carotene and dietary fibre was developed through incorporation of orange peel products. The suitability of two forms of peel viz., candied orange peel (COP) and orange peel powder (OPP), was studied as flavour adjunct in frozen yoghurt. The medium-fat frozen yoghurt mix was prepared by blending yoghurt base with ice cream mix (25:75, w/w). COP and OPP were used as flavour adjuncts at levels of 8.0 and 2.5% by weight of mixes, respectively. The control (C) frozen yoghurt was devoid of the fruit peel. Incorporation of peel solids yielded frozen yoghurts which had markedly higher protein, carbohydrates, ash and total solids content. OPP used at 2.5% level was preferred over use of COP at 8.0% level as a valued ingredient in the preparation of ‘medium-fat orange frozen yoghurt’. Such product had superior total sensory score when compared to the rest of the samples. The recommended frozen yoghurt was higher in terms of β-carotene and dietary fibre by 37.20 and 240.0%, respectively, compared to control product. 相似文献
49.
Majdy M. Eltahir Adil Yousif Fadwa Alrowais Mohamed K. Nour Radwa Marzouk Hatim Dafaalla Asma Abbas Hassan Elnour Amira Sayed A. Aziz Manar Ahmed Hamza 《计算机、材料和连续体(英文)》2023,75(2):3239-3255
The human motion data collected using wearables like smartwatches can be used for activity recognition and emergency event detection. This is especially applicable in the case of elderly or disabled people who live self-reliantly in their homes. These sensors produce a huge volume of physical activity data that necessitates real-time recognition, especially during emergencies. Falling is one of the most important problems confronted by older people and people with movement disabilities. Numerous previous techniques were introduced and a few used webcam to monitor the activity of elderly or disabled people. But, the costs incurred upon installation and operation are high, whereas the technology is relevant only for indoor environments. Currently, commercial wearables use a wireless emergency transmitter that produces a number of false alarms and restricts a user’s movements. Against this background, the current study develops an Improved Whale Optimization with Deep Learning-Enabled Fall Detection for Disabled People (IWODL-FDDP) model. The presented IWODL-FDDP model aims to identify the fall events to assist disabled people. The presented IWODL-FDDP model applies an image filtering approach to pre-process the image. Besides, the EfficientNet-B0 model is utilized to generate valuable feature vector sets. Next, the Bidirectional Long Short Term Memory (BiLSTM) model is used for the recognition and classification of fall events. Finally, the IWO method is leveraged to fine-tune the hyperparameters related to the BiLSTM method, which shows the novelty of the work. The experimental analysis outcomes established the superior performance of the proposed IWODL-FDDP method with a maximum accuracy of 97.02%. 相似文献
50.
Recording a personal life log (PLL) of daily activities in a ubiquitous environment is an emerging application of information
technology. In this work, we present a single tri-axial accelerometer-based PLL system capable of human activity recognition
and exercise information generation. Our PLL system exhibits two main functions: activity recognition and exercise information
generation. For activity recognition, the system first recognizes a state of daily activities based on the statistical and
spectral features of the accelerometer signals. An activity within the recognized state is then recognized using a set of
augmented features, including autoregressive coefficients, signal magnitude area, and tilt angle, via linear discriminant
analysis and hierarchical artificial neural networks. Upon the recognition of each activity, the system further estimates
exercise information that includes energy expenditure based on metabolic equivalents, stride length, step count, walking distance,
and walking speed. Our PLL system operates in real-time, and the life log information it generates is archived in a daily
log database. We have validated our PLL system for six daily activities (i.e., lying, standing, walking, going-upstairs, going-downstairs,
and driving) via subject-independent and subject-dependent recognition on a total of twenty subjects, achieving an average
recognition accuracy of 94.43 and 96.61%, respectively. Our results demonstrate the feasibility of a portable real-time PLL
system that could be used for u-lifecare and u-healthcare services in the near future. 相似文献