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91.
92.
Hassan Fathabadi 《International Journal of Green Energy》2020,17(12):742-755
ABSTRACT In this paper, a novel evacuated tube solar collector (ETSC) is first designed and built. Then, the impact of adding reflector, reflector plus single-axis sun tracker and reflector plus two-axis sun tracker to the built ETSC on the thermal efficiency of the ETSC is evaluated both theoretically and experimentally. In this regard, four identical versions of the proposed ETSC have been built and utilized in four collectors built and presented in this research work. The first collector is the same proposed built ETSC, the second collector is a parabolic trough solar collector comprising one built ETSC and a reflector (ETSC+R), the third collector is composed of one built ETSC, a reflector and a single-axis sun tracker all built in this study (ETSC+R+ ST), and the fourth collector consists of one built ETSC, a reflector and a two-axis sun tracker all built in this study (ETSC+R+ DT). Theoretical basis and concepts of the four collectors are formulated and analyzed in separate subsections. Theoretical results are outlined and highlighted at the end of each subsection. Experimental measurements and data obtained from the operation of the four collectors in the four seasons are presented that point by point verify theoretical results obtained in this study. To provide a comprehensive view, a techno-economic numerical comparison is performed between the four collectors. The following points, which are also the novelty and contributions of this work, are deduced from theoretical concepts, experimental data, and comparison provided in this study: ?There is no technical and economic justification for adding a reflector to an ETSC that results in forming a parabolic trough solar collector (ETSC+R) without any sun tracker. ?There is no economic justification for adding a single-axis sun tracker to a parabolic trough solar collector (ETSC+R). ?There is no economic justification for adding a two-axis sun tracker to a parabolic trough solar collector (ETSC+R). ?Comparing between a two-axis sun tracker and a single-axis sun tracker, adding the single-axis type to a parabolic trough solar collector (ETSC+R) is more advantageous. 相似文献
93.
Hassan OA 《Journal of environmental management》2004,70(2):181-187
The decision of selecting building structures with respect to the environmental demand is an issue commonly addressed in environmental management. In this paper, the importance of considering the decision analysis technique value-focused thinking in the environmental selection of wall structures is investigated. In this context, a qualitative value model is developed in which the external and internal environmental factors are considered. The model is applied on a case study in which a decision should be made on three categories of exterior wall structures: wood, masonry and concrete. It is found that the wall structure made of wood is the most compatible option with respect to the external and internal environmental requirements of building structures. 相似文献
94.
Marwan A. Hassan Dan L. Hogan Stephen A. Bird Christine L. May Takashi Gomi David Campbell 《Journal of the American Water Resources Association》2005,41(4):899-919
This paper synthesizes information on the spatial and temporal dynamics of wood in small streams in the Pacific Northwest region of North America. The literature on this topic is somewhat confused due to a lack of an accepted definition of what constitutes “small” streams and what is the relative size of woody debris contained within the channel. This paper presents a matrix that defines woody debris relative to channel size and then discusses the components of a wood budget. Headwater streams are in close proximity to wood sources and, in steeplands, are often tightly constrained by steep hillslopes. Special consideration is given to ecosystem characteristics and to management practices that affect the wood dynamics in this context. Knowledge gaps and uncertainties that can be used to guide future research are identified. Very little is currently known about the role of mass wasting in wood recruitment and storage relative to other processes, such as bank erosion and mortality, in larger streams. Further, very little work has addressed the relative importance of different wood depletion processes, especially those associated with wood transport. The effect of other ecosystem variables on wood dynamics locally across a watershed (from valley bottom to mountaintop) and regionally across the landscape (from maritime to continental climates) is not addressed. Finally, the scientific community has only begun to deal with the effects of management practices on wood quantity, structure, and movement in small streams. 相似文献
95.
Iqbal Kashif Hassan Syed Tauseef Peng Hui Khurshaid 《Environmental science and pollution research international》2019,26(15):15153-15161
Environmental Science and Pollution Research - Economic growth in modern-day world get attention primarily through innovation and higher productivity, which places technology and knowledge at the... 相似文献
96.
Sabouni Rana Gomaa Hassan 《Environmental science and pollution research international》2019,26(6):5372-5380
Environmental Science and Pollution Research - This research paper presents the results of an experimental investigation of the degradation of three different contaminants including progesterone... 相似文献
97.
Saleemi Muhammad Kashif Tahir Muhammad Waseem Abbas Rao Zahid Akhtar Masood Ali Aamir Javed Muhammad Tariq Fatima Zahida Zubair Muhammad Bhatti Sheraz Ahmed Zahoor Ul Hassan 《Environmental science and pollution research international》2019,26(21):21371-21380
Environmental Science and Pollution Research - Cadmium is an important widely distributed heavy metal in the environment due to its several industrial uses, while milk thistle is an important herb... 相似文献
98.
Mazlita Yahya You Wei Chen Hwei Voon Lee Wan Hasamudin Wan Hassan 《Journal of Polymers and the Environment》2018,26(7):2825-2844
This study investigates for the first time the feasibility of isolating nanocellulose from several selected feedstocks via a novel Ni(II)-hydrolysis process, including lignocellulosic biomasses (oil palm trunk, banana peel and coconut husk) and processed biomasses (newspaper, tissue paper and cotton linter), with an obtained gravimetric yield ranging from 59.6 to 86.2%. The isolation of nanocellulose products from these selected feedstocks was verified by the successive removal of most of their non-cellulosic components (lignin and hemicellulose) and cellulose amorphous regions, the increase in the crystallinity index and the nanoscale of the individual crystals. Most importantly, the resultant nanocellulose products rendered better thermal stability than that of corresponding original sources, which are highly potential to be utilized as the new renewable sources of reinforcement materials with potential applications in bio-nanocomposites and thermoplastics. Therefore, this work proves the viability of direct production of nanocellulose from a variety of cellulosic sources by using Ni(II)-based transition metal salt catalyst. The results suggested that the concept of waste to wealth could be well executed from the obtained nanocellulose, which are greatly potential for various industrial applications. 相似文献
99.
Mohammad Naghi Adel Hassan Pourbabaei Seyed Jalil Alavi Ali Salehi 《Russian Journal of Ecology》2017,48(3):219-225
The aim of this study was to determine type of response curves for seventeen woody species (10 tree and 7 shrub species) to soil factors in an intact riparian forest in Safaroud River in northern Iran using HOF function. Data were collected along transects established perpendicular to the water flow on both sides of the river. Results indicated different responses for different woody species. The most common were symmetricunimodal response curves and curves showing an increase in occurrence probability after a certain value in form of a plateau. Bimodal curves were four times more frequent in riverside than forest interior area. It seems that river flow disturbances through frequent floods effect on species tolerance and optimum in riversides. 相似文献
100.
Bilal Muhammad Qadir Abdul Yaqub Atif Hassan Habib Ul Irfan Muhammad Aslam Mehmood 《Environmental science and pollution research international》2023,30(1):727-738
Environmental Science and Pollution Research - Microplastics (MP) pollution is an emerging threat to life and the environment. These particles are not restricted to human-inhabited lands but also... 相似文献