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41.
42.
Flocculation of river silt using chitosan   总被引:8,自引:0,他引:8  
Divakaran R  Pillai VN 《Water research》2002,36(9):2414-2418
Flocculation of silt in river water using chitosan was studied in the pH range 4-9, and suspended solid concentrations in the range 20-80 mg/L. Chitosan effectively reduces turbidity due to silt by flocculation and settling. Flocculation efficiency is very sensitive to pH, and reaches a maximum at pH 7. The optimal chitosan concentration required to effect flocculation is 0.5 mg/L and is independent of silt concentration within the range examined. Restabilisation of the suspension is observed at higher concentrations of chitosan, and the amount required for restabilisation increases with increasing concentration of suspended solids. Flocculation is faster at higher concentrations of silt and the flocs are large and fibrous.  相似文献   
43.
Scope : Dietary proteins and essential amino acids (EAAs) are the major nutritional supplements that support the growth and activity of gut microbes contributing to the wellbeing of their host. This study hypothesizes that daily supplementation of the diet with either EAAs or whey protein for 12 weeks would improve the gut microbiome of older adults. Methods and results : The stool samples are processed and subjected to Illumina-based 16S ribosomal ribonucleic acid (rRNA) gene amplicon sequencing. In both groups, the most abundant families are found in order of relative abundance included: Bacteroidaceae, Lachnospiraceae, Ruminococcaceae, Prevotellaceae, Rikenellaceae, Enterobacteriaceae, Oscillospiraceae, Tannerellaceae, and Akkermansiaceae, which indicate that these subjects are able to maintain a same healthy microbial diversity in their guts. A significant finding is a reduction of proinflammatory cytokine, interleukin-18 (IL-18) in the EAAs group. It also uses the standard 6-min walking test (6MWT) as a measure of cardiopulmonary fitness. At the end of the study, the subjects in the EAAs group perform significantly better in the 6MWT as compared to the whey group. Conclusion : It seems plausible that the improved physical performance and reduced proinflammatory cytokine, IL-18 seen in the EAAs group, are independent of changes in gut microbiota.  相似文献   
44.
Cloud computing has been gaining widespread significance in recent times, especially with the advent of state‐of‐the‐art communication technologies and data‐handling systems. Large volumes of data are being handled in real time and their availability is made feasible to consumers in an efficient manner through cloud computing networks. However, security of such data being transferred through clouds characterized in a centralized configuration is of prime concern, which has been investigated in this research paper. Secured transmission of data through a secured key transmission using appropriate authentication mechanism has been the driving force behind the research carried out in this paper. In order to resolve the existing issues in clouds in terms of computational as well as storage complexities, a secure key transmission Rivest‐Shamir‐Adleman (SKT‐RSA) protocol is proposed based on the secure key transmission. Key distribution between the certified authority and the end user is proposed. The proposed protocol is a tree‐based cluster key distribution scheme.  相似文献   
45.
In this paper, silicon nanotube field effect transistors (SiNT-FETs) are investigated for independent gate operation using 3D numerical simulation. The parameters, \(\mathrm{I_{ON} , I_{OFF}, V_{T}}\), and the unity gain cut-off frequency \(\mathrm{(f_{T}}\)) are studied in the independent-gate mode. The SiNT-FET we have considered has two gates, namely outer and inner gates, and can be simultaneously driven or independently driven. The physical gate oxide thicknesses of the outer and inner gates of the device are to be converted into effective gate oxide thicknesses due to the non-Euclidean geometry associated with the tube structure. The effective gate oxide thicknesses are different for the same outer and inner physical gate oxide thickness. Since the inner and outer gates are asymmetric, the device parameters extracted at the outer and inner gates are different. Since the independent gate operation allows dynamic threshold voltage adjustment, a model to predict the threshold voltage also known as the threshold voltage sensitivity model is developed for the SiNT device by modifying the double gate FinFET model. These models are verified by TCAD simulation results to validate their accuracy.  相似文献   
46.

During disasters, multimedia content on social media sites offers vital information. Reports of injured or deceased people, infrastructure destruction, and missing or found people are among the types of information exchanged. While several studies have demonstrated the importance of both text and picture content for disaster response, previous research has primarily concentrated on the text modality and not so much success with multi-modality. Latest research in multi-modal classification in disaster related tweets uses comparatively primitive models such as KIMCNN and VGG16. In this research work we have taken this further and utilized state-of-the-art models in both text and image classification to try and improve multi-modal classification of disaster related tweets. The research was conducted on two different classification tasks, first to detect if a tweet is informative or not, second to understand the response needed. The process of multimodal analysis is broken down by incorporating different methods of feature extraction from the textual data corpus and pre-processing the corresponding image corpus, then we use several classification models to train and predict the output and compare their performances while tweaking the parameters to improve the results. Models such as XLNet, BERT and RoBERTa in text classification and ResNet, ResNeXt and DenseNet in image classification were trained and analyzed. Results show that the proposed multimodal architecture outperforms models trained using a single modality (text or image alone). Also, it proves that the newer state-of-the-art models outperform the baseline models by a reasonable margin for both the classification tasks.

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47.
ABSTRACT

The paper comprises Energy Audit of Mechanical Equipment in HPCL (Hindustan Petroleum Corporation Limited), Mazgaon Dock, Mumbai. It represents the energy audit of counter-flow-type-induced draft cooling tower and other mechanical equipment. The technical data have been taken from Paharpur cooling tower (series 3800) HPCL, Mazgaon. Lube Plant 1 Cooling towers are generally heat-removal devices for industrial processes as well as for for chemical plants. The present review is aimed at study and research on the cooling tower for increasing the efficiency and power savings to make it more economical and efficient. Using boiler of high efficiency helps in reducing the cost which is an important factor in industries and to reduce the emissions. The direct efficiency method can be used but it does not focus on energy losses so the standard methods are used. But the modified Siegert’s equation is a very common equation for finding out the boiler efficiency.  相似文献   
48.
One of the main challenges in implementing sensor devices for internet of things (IoTs), is the means for the operating power supply. RF energy harvesting (RFEH) presents a promising solution as RF power is a suitable choice particularly for cases where solar harvesting is not feasible. However, in spite of RF communication system design being a well‐established, there are several challenges poised for the implementation of the RFEH systems especially for harvesting the ambient RF signals. The challenges can be widely categorized as the overall conversion efficiency, bandwidth, and form factor. In this article, an exhaustive survey on the different RFEH system that is reported is carried out and discussed. Important design issues are identified with insights drawn. First, we have presented the challenges in designing antennas for RFEH systems. This is followed by rectifier circuits and matching networks, and eventually a general frame work for designing of ambient RFEH systems is deduced.  相似文献   
49.
The water resources of the Koshi Basin (87,311 km2) are largely untapped, and while proposals for their development exist, their impacts on current and future water demand are not quantified. The current study is the first to evaluate the impacts of 11 proposed development projects for hydropower generation and water storage. We find that 29,733 GWh of hydropower could be generated annually and 8382 million m3 of water could be stored. This could satisfy unmet demand in the current (660 million m3) basin situation and in future scenarios – i.e. population, agricultural and industrial growth – that are projected to have 920, 970 and 1003 million m3 of unmet demand, respectively, by 2050.  相似文献   
50.
Plankton are highly sensitive to environmental changes, therefore being excellent water indicators. This study was conducted to classify water and sediment quality characteristics and different genera of phytoplankton and zooplankton in three ponds. The prominent water and sediment quality characteristics responsible for the occurrence of phytoplankton and zooplankton were also studied. The nutrient pollution factor is mainly responsible for the abundance of Cyanophyceae and for reduction in Rotifera, Cladocera, Copepoda and Ostracoda. The organic pollution factor is responsible for the abundance of Bacillariophyceae and Protozoa. The products of mineralization have more influence on the decreased Chlorophyceae. Thus, it is essential to control the disposal of pollutants into the study pond system.  相似文献   
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