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Number of results: 6
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Abstract

This study analyses and presents a technical comparison of seepage estimation from 11 empirical equations with measured seepage losses by the inflow-outflow method from two lined and unlined secondary irrigation canals sub-divided into different reach lengths. A significant margin of error was observed between empirical and inflow- outflow methods, hence modifications in empirical equations were performed. Results reveal that the average seepage losses observed in unlined and lined canals by inflow-outflow method were 9.15 and 3.89%, respectively. Moreover, only the Chinese equation estimated seepage losses for an unlined canal as similar to observed losses (0.11 m 3∙s –1) whereas the Indian equation estimated similar results for a lined canal to those observed in the field (0.09 m 3∙s –1). However, the rest of empirical equations were modified in accordance with error percentage with regard to the observed losses. The empirical equations were then observed to estimate reliable results of seepage.
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Authors and Affiliations

Naeem S.B. Syed
1
ORCID: ORCID
Zhao Shuqi
1
ORCID: ORCID

  1. Beijing University of Technology, Faculty of Architecture, Civil and Transportation Engineering, 100124 Beijing, China
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Abstract

In this study, female gametophytes of Silene muradica, which is a gynodioecious species, were examined histologically. Buds and blossoms of S. muradica were used as the research material. They were collected in the Sivas province (Turkey) in July 2019, and fixed with ethanol:acetic acid solution (3:1, v/v). Flower parts were dissected under a stereo microscope. They were dehydrated in rising alcohol series and then embedded in Historesin. The sections were taken by a rotary microtome and stained with 0.5% Toluidine blue O. The ovary of S. muradica has three carpels and a single chamber, the ovules are arranged on a central column. The mature ovule is of the campylotropous type, crassinucellate and bitegmig. The megaspore mother cell undergoes regular meiotic division and forms a linear megaspore tetrad after meiosis. The development of the embryo sac is monosporic. The chalazal megaspore is functional and the others degenerate. The mature embryo sac is eight-nucleated and of the Polygonum type. The synergid cells and the egg cell are completely surrounded by the cell wall. Antipodal cells are temporary cells, which degenerate immediately after fertilization. Before fertilization, polar nuclei are fused in the central cell and form the secondary nucleus. The endosperm development is of the nuclear type. Nucellar tissue is permanent and forms perisperm in mature seeds. The embryo development is of the Caryophyllad type. In this study, the development of the female gametophyte of S. muradica, which was determined to be a gynodioecious species, was reported for the first time.
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Authors and Affiliations

Ciler Kartal
1
ORCID: ORCID
Mehmet Tekin
2
ORCID: ORCID

  1. Department of Biology, Faculty of Science, Trakya University, Edirne, Turkey
  2. Department of Pharmaceutical Botany, Faculty of Pharmacy, Trakya University, Edirne, Turkey
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Abstract

Rubberized concrete is made up of scrap tyre rubbers where the fine aggregate is partially replaced by it, as the waste rubber is being a threat to the environment. It is estimated that only 4% of the waste tyre is used in the application of civil engineering and also there is shortage of fine aggregates. The primary objective of this study is to investigate the preliminary concrete properties of M25 and M30 concretes. The fine aggregate is replaced by pre-treated crumb rubber with 10, 15 and 20 % of total weight. Various tests are conducted on the rubberized concrete specimens such as compressive strength, split tensile strength, flexural strength and slump test. The investigation is carried out to determine the impact load behavior of hybrid rubberized composite slabs. In addition 0%, 1%, 1.5%, and 2% of replacement of rubber fibers for total weight of coarse aggregate is also made. The specimen of size 300 mm x 300 mm x 50 mm thickness is subjected to drop hammer test to find its performance against the impact loads. The number of blows for the first crack and complete failure of slab was found and the characteristics were studied.

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Authors and Affiliations

P. Subashree
R. Thenmozhi
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Abstract

Mezyn National Natural Park is in the north part of the Korop District of the Chernihiv Region, 310 km2 in area, is characteristic for its strongly dismembered landscape that stipulates presence of varied localities, among them there are exterminated glaciofluvial plains, slopes and super streamside terraces. Aim of research included an expose of the value of the Mezyn NNP in maintenance of forest diversity of vascular plants and forest communities. In the Mezyn NNP there are 772 species of spontaneous flora, 194 species of the cultivated flora and 18 rarity species. The rarest species are concentrated in the centre and the east, prats of the park richer in vegetation cover. In the forest group of the Mezyn NNP 10 species of vascular plants are recordered in the Red book of the Ukraine. The wooden territory of the Mezyn NNP presents 38% and provides the variety of ecotopic terms after they provides a wide spectrum of representation and protection of forest species of vascular plants and corresponding phytocommunites.

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Authors and Affiliations

Yurii Каrpenko
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Abstract

On the basis of about 12500 depth measurements of which 6700 were taken from r/v Profesor Siedlecki, 1300 from r/v Polarstern and the remainder from British navigation charts, a bathymetric chart of the Bransfield Strait in the scale 1:500 000 has been prepared. Within the assumed boundaries the total area of the Bransfield Strait covers 65308.6 square kilometres, of which the Western Basin covers 23.5%, Central Basin — 47.3%, and Eastern Basin 29.2%. Capacity of the whole Bransfield Strait amounts to 38451 km3 . The average depth of the Bransfield Strait is 592 m.

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Authors and Affiliations

Jan Szeliga
Stanisław Rakusa-Suszczewski
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Abstract

Groundwater mapping plays an important role in effective water resource management, sustainable development, and environmental protection. In the tropical Brunei Darussalam (north Borneo Island), groundwater mapping is yet to be provided. The aim of the study is to provide groundwater mapping of Brunei, particularly for the urban and coastal areas of the Brunei-Muara capital district. The study uses a GIS interpolation technique to generate a groundwater contour map based on groundwater data from 572 sacrificial boreholes located in the study area. Remote sensing data and published maps from secondary sources were digitised in ArcGIS software to produce thematic layers for further hydrological evaluations. Results showed that groundwater levels in the study area are generally high and shallow, ranging from 0 to 18 m below ground level with a mean value of 2.9 m. According to the evaluation of geo-thematic layers and groundwater contours, groundwater flows towards the South China Sea in the coastal areas and towards the Brunei River further inland. Hydraulic gradients towards the South China Sea also vary between 0.004 and 0.08. Thus, assuming surface aquifer thickness in the weathered zone between 10 to 20 m, hydraulic conductivities ranges from 1∙10−5 to 1∙10−4 m∙s−1, a submarine groundwater discharge (SGD) flux between 4.7∙10−7 to 4.0∙10−4 m3∙s−1 per unit width can be estimated for the shallow aquifer. This study provides valuable insights into the groundwater system dynamics so important, which are critical for its future utilisation and protection, aiming to contribute to the national water security in Brunei Darussalam.
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Authors and Affiliations

Hakimmi Abidin
1
ORCID: ORCID
Siti Lieyana Azffri
1
ORCID: ORCID
Emelia Nirus
1
ORCID: ORCID
Asri Suhip
2
ORCID: ORCID
Afiq Aiman Jaya
2
ORCID: ORCID
Stefan Herwig Gödeke
1
ORCID: ORCID

  1. Universiti Brunei Darussalam, Geoscience Programme, Faculty of Science, Jalan Tungku Link, Gadong, BE1410, Bandar Seri Begawan, Brunei Darussalam
  2. Ministry of Development, Public Works Department, Geological and Geotechnical Section, Jalan Lapangan Terbang Lama, Berakas, BB3510, Bandar Seri Begawan, Brunei Darussalam

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