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11.
The objectives of this article is to propose a new drying model for the second falling rate period known as the variable diffusion controlled period that follows after the first falling rate period and to propose a new method to determine the second critical moisture content that separates these two periods. Experimental work on paddy drying at minimum fluidization velocity was carried out in a rapid bin dryer. The effects of operating temperatures (60-120°C) and bed depths (2-6 cm) on the paddy drying characteristics were investigated. It was found that the normalized drying rate of paddy was proportional to the normalized moisture content in the first falling rate period but in the second falling rate period, the normalized drying rate of the material varies exponentially with the normalized moisture content. The different relationship between the normalized drying rate and the normalized moisture content in the first and second falling rate periods indicate that two different mechanism of moisture transport are at work. The new exponential model of the second falling rate period and the linear model of the first falling rate period were found to fit the experimental data very well. Derivation from variable diffusion equation shows that the linear model is the result of constant diffusion coefficient whereas the new exponential model is the result of linear diffusion coefficient. This also implies that the first falling rate period is a constant diffusion controlled period and the second falling rate period is a variable diffusion controlled period. In addition, drying kinetics data of a drying process that fits the exponential model over a very slow drying period will show that the drying process is under the effect of a linear diffusion coefficient. It was also found that the proposed new method to determine the second critical moisture content that distinguishes between the first and second falling rate periods by using a sudden change in the value of the drying rate gradient to a much lower value at that point is more rigorous and yet simpler than the method of determining the specific location of the receding drying boundary since it is based on the behavior of the actual drying kinetic data. 相似文献
12.
Kolivand Hoshang Joudaki Saba Sunar Mohd Shahrizal Tully David 《Neural computing & applications》2021,33(10):4945-4963
Neural Computing and Applications - Hand pose tracking is essential in sign languages. An automatic recognition of performed hand signs facilitates a number of applications, especially for people... 相似文献
13.
Izzuddin Tarmizi Ahmad Safri Norlaili Mat Othman Mohd Afzan 《Neural computing & applications》2021,33(11):6233-6246
Neural Computing and Applications - This paper introduces the use of the one-dimensional convolutional neural network (1D-CNN) for end-to-end EEG decoding with application towards a BCI system with... 相似文献
14.
Mohd Akram Hira Lal Mohammad Osama Farah Ansari Sana Anwar Kabir-ud-Din Ajaz Ahmad Samreen Naved Azum Hadi M. Marwani Abdullah M. Asiri 《Journal of surfactants and detergents》2021,24(1):35-49
In this study, we prepared a novel series of diester-functionalized cationic gemini surfactants (Cm-E2O2-Cm) containing ethylene oxide as a spacer with varying alkyl chain lengths and characterized by 1H NMR, FT-IR, elemental analysis, and ESI-MS. The physicochemical properties of the geminis were explored by tensiometry, fluorescence, dye solubilization, and Krafft point. These geminis acquire superior surface activity than the conventional surfactants. Fluorescence spectroscopy analysis affirmed that the micropolarity and aggregation number of micelles diminished with increase in the alkyl chain length. These geminis represent a new group of amphiphiles of considerably high biodegradability, better cleavability, and low toxicity as assessed by BOD test, FT-IR analysis, and HC50 analysis, respectively. They also showed significant level of antimicrobial activity toward some specified bacterial strains of Gram-positive and Gram-negative by using agar well diffusion method. Furthermore, the thermogravimetric analysis provided information regarding thermal stabilities of the newly synthesized gemini surfactants. 相似文献
15.
Mohd N. Mat Nor Ilva D. Rupenthal Colin R. Green Monica L. Acosta 《International journal of molecular sciences》2021,22(4)
Dysregulation of retinal function in the early stages of light-induced retinal degeneration involves pannexins and connexins. These two types of proteins may contribute to channels that release ATP, leading to activation of the inflammasome pathway, spread of inflammation and retinal dysfunction. However, the effect of pannexin channel block alone or block of both pannexin channels and connexin hemichannels in parallel on retinal activity in vivo is unknown. In this study, the pannexin channel blocker probenecid and the connexin hemichannel blocker tonabersat were used in the light-damaged rat retina. Retinal function was evaluated using electroretinography (ERG), retinal structure was analyzed using optical coherence tomography (OCT) imaging and the tissue response to light-induced injury was assessed immunohistochemically with antibodies against glial fibrillary acidic protein (GFAP), Ionized calcium binding adaptor molecule 1 (Iba-1) and Connexin43 (Cx43). Probenecid did not further enhance the therapeutic effect of connexin hemichannel block in this model, but on its own improved activity of certain inner retina neurons. The therapeutic benefit of blocking connexin hemichannels was further evaluated by comparing these data against results from our previously published studies that also used the light-damaged rat retina model. The analysis showed that treatment with tonabersat alone was better than probenecid alone at restoring retinal function in the light-damaged retina model. The results assist in the interpretation of the differential action of connexin hemichannel and pannexin channel therapeutics for potential treatment of retinal diseases. 相似文献
16.
Shaikh Mohd Rizwan Uddin Loan Sajad A. Alharbi Abdullah G. 《Journal of Computational Electronics》2021,20(6):2360-2368
Journal of Computational Electronics - In this work, a Schottky junction on the drain side employing low workfunction (WF) metal is proposed as a method to suppress the OFF-state leakage in... 相似文献
17.
Fatin N. Mohd Jaya Sergio G. Garcia Francesc E. Borras Dolores Guerrero Godfrey C. F. Chan Marcella Franquesa 《International journal of molecular sciences》2021,22(9)
Regulatory B (Breg) cells are endowed with immune suppressive functions. Various human and murine Breg subtypes have been reported. While interleukin (IL)-10 intracellular staining remains the most reliable way to identify Breg cells, this technique hinders further essential functional studies. Recent findings suggest that CD9 is an effective surface marker of murine IL-10 competent Breg cells. However, the stability of CD9 and its relevance as a unique marker for human Breg cells, which have been widely characterized as CD24hiCD38hi, have not been investigated. Here, we demonstrate that CD9 expression is sensitive to in vitro B cell stimulations. CD9 expression could either be re-expressed or downregulated in purified CD9-negative B cells and CD9-positive B cells, respectively. We found no significant differences in the Breg differentiation capacity of the CD9-negative and CD9-positive B cells. Furthermore, CD9-positive B cells co-express CD40 and CD86, suggesting their nature as B cell activation or co-stimulatory molecules, rather than regulatory ones. Therefore, we report the relatively unstable CD9 as a distinct surface molecule, indicating the need for further research for a more reliable marker to purify human Breg cells. 相似文献
18.
Previously obtained cloud point curves for mixtures of oligomeric poly(dimethyl siloxanes) (weight fraction W1) with oligomeric polyethylenes have been supplemented by the use of samples of higher molecular weight. Initial flat regions at low-medium W1 as well as a slight shoulder at extremely high W1 are now considered to be due to crystallization, since the temperatures at which they occur are the melting points of the oligoethylenes. The actual cloud point curves were of an unsymmetrical dome shape, the form of which could not be simulated by using a concentration-independent interaction parameter g in the Flory-Huggins equation. However, spinodals calculated by assuming a quadratic dependence of g on composition were of the same shape as the experimental cloud point curves. The critical compositions calculated on this basis were also close to the experimental ones. 相似文献
19.
The application of supercritical fluid chromatography (SFC) coupled with a UV variable-wavelength detector to isolate the
minor components (carotenes, vitamin E, sterols, and squalene) in crude palm oil (CPO) and the residual oil from palm-pressed
fiber is reported. SFC is a good technique for the isolation and analysis of these compounds from the sources mentioned. The
carotenes, vitamin E, sterols, and squalene were isolated in less than 20 min. The individual vitamin E isomers present in
palm oil were also isolated into their respective components, α-tocopherol, α-tocotrienol, γ-tocopherol, γ-tocotrienol, and
δ-tocotrienol. Calibration of all the minor components of palm as well as the individual components of palm vitamin E was
carried out and was found to be comparable to those analyzed by other established analytical methods. 相似文献
20.
Mohd Hilmi Hasan Jafreezal Jaafar Mohd Fadzil Hassan 《Artificial Intelligence Review》2014,42(4):835-850
Monitoring Quality of Service (QoS) compliance is an important procedure in web service environment. It determines whether users’ expectations are met, and becomes the vital factor for them to decide whether to continue paying for the service or not. The monitoring is performed by checking the actual services performance against the QoS stated in Service Level Agreement (SLA). In relation to that, the need for monitoring vague QoS specifications in SLA has become more apparent nowadays. This paper reviews the published literature on web services QoS monitoring. A total of 60 selected articles were systematically analyzed. There were 23 of the articles selected through restrictive search criteria while the other 37 were selected based on unrestrictive search criteria. The review shows that little evidence exists on monitoring vague QoS specifications of web services. Providing ability for monitoring QoS that is specified vaguely in SLA could give new insights and implications to web services field. This paper concludes with some recommended future works to construct the theory and perform the empirical research. 相似文献