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The purpose of this paper is to explore the basic loading state in local loading forming process of large-sized complicated rib-web component, which is important for understanding process characteristic, controlling metal flow and designing preformed geometry of the local loading forming process. Moreover the analytical models for different loading states are established to quickly predict the metal flow.

Through analysis of geometric characteristic of large-sized complicated rib-web component and the deformation characteristic on planes of metal flow by local loading method, a representative cross-section is put forward and designed, which could reflect the local loading forming characteristics of large-sized complicated rib-web component. Finite element method (FEM) is used to analyze the stress and metal flow, and the analytical models of metal flow are established by using slab method (SM).

Three local loading states and one whole loading state are found in the local loading forming process of representative cross-section. Further, four loading states also exist in local loading forming process of large-sized complicated rib-web components. With the metal distribution in the process, some local loading states may turn into whole loading state. For the representative cross-section, the relative error of metal distribution between SM and FEM results is less than 15 per cent, and the relative error of metal in the rib cavity between SM and FEM results is less than 10 per cent.

Metal flow can be controlled by adjusting the loading states in the process. According to the metal flow laws in different loading states, a simple unequal-thickness billet can be designed to achieve initial metal distribution, and then, the secondary metal distribution can be achieved in the process.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

The purpose of this paper is to describe the investigation of distribution of metals in water and sediment samples of Poydras‐Verret wetland, an area that has received approximately 40 years input of secondarily treated municipal effluent.

Water and sediment samples were analyzed for metals for a period of 18 months. These metals were also monitored for the secondarily treated effluent, and at a reference/control wetland that does not receive wastewater. Analysis of variance (ANOVA) and Student Newman‐Keuls post‐hoc ANOVA analysis were conducted to evaluate the pattern of metal distribution within the Poygras‐Verret wetland and compare results to the reference wetland. Heavy metal criteria established by United States Environmental Protection Agency (USEPA) and State of Louisiana were also used to assess the potential chronic and acute health impacts of heavy metals in the Poydras‐Verret wetland.

Concentrations of metals of the Poydras‐Verret wetland water are not different from those found in the reference wetland water, suggesting no observed accumulation of these metals within the receiving wetland water. All metals are below the acute criteria.

Historical data regarding metal accumulation in wetlands in the published literature is limited. This paper provides supporting evidence that using wetlands to assimilate wastewater could be a long‐term, practical solution with the side benefits including wetland restorations and protection from wave erosion and storm surge.

One of the problems that urbanization creates on the ecosystem is the increase of heavy metal accumulation of the urban lands. Due to constant urbanization and industrialization in many parts of the world, metals are constantly spreading to the environment and pose a great threat to human health. The purpose of the study is to determine the effect of heavy metal accumulation values of the lands located in Bingöl city center on the urban ecosystem by examining them in terms of zonal and land-use classification.

The research was conducted on 30 samples taken from five zones and six land-use classes (traffic area-TA, school area-SA, commercial-industry area-CA, green space-GS, residential area-RA and open space-OS). Heavy metal deposits of soil samples were determined in accredited laboratories using the Inductively Coupled Plasma – Mass Spectrometer (ICP-MS) and Atomic Absorption Spectrometer (AAS) device. The study employed the SPSS program for statistical analysis of laboratory results, and ArcGIS Pro programs were used to determine spatial pollution distribution.

Although the heavy metal contents of soil samples pose no problems in terms of national and international standards, a number of zones carry risks for the future. In the analyzes, traffic and settlement area soils in terms of land-use classifications and Zone 5 soils in terms of zonal distribution were determined as ecologically risky areas.

The study provided suggestions on what should be done to use the results of the research in planning the physical development of the city.

In the present research, a numerical investigation is carried out to study the fluid flow and heat transfer in a double-pipe, counter-flow heat exchanger exploiting metal foam inserts partially in both pipes. The purpose of this study is to achieve the optimal distribution of a fixed volume of metal foam throughout the pipes which provides the maximum heat transfer rate with the minimum pressure drop increase.

The governing equations are solved using the finite volume method. The metal foams are divided into different number of parts and positioned at different locations. The number of metal foam parts, their placements and their volume ratios in each pipe are sought to reach the optimal conditions. The four-piece metal foam with optimized placement and partitioning volume ratios is selected as the best layout. The effects of the permeability of metal foam on the Nusselt number, the performance evaluation criteria (PEC) and the overall heat transfer coefficient are investigated.

It was observed that the heat transfer rate, the overall heat transfer coefficient and the effectiveness of the heat exchanger can be improved as high as 69, 124 and 9 per cent, respectively, while the highest value of PEC is 1.36.

Porous materials are widely used in thermo-fluid systems such as regenerators, heat sinks, solar collectors and heat exchangers.

Having less pressure drop than fully filled heat exchangers, partially filled heat exchangers with partitioned metal foams distributed optimally enhance heat transfer rate more economically.

This study aims to examine the metal pollution in coastal sediment in the Peninsular Malaysia.

Approximately 141 published studies were screened from 1,285 documents and reviewed to determine the existing pollution status in the coastal areas of Peninsular Malaysia and the metals under review were Pb, Hg, Cd, Ar, Cu, Zn, Cr and Ni. Sources of pollutants and their effect on biological systems, marine organisms and human health were addressed in this review as well as recommendation of heavy metal removal or remedies in short. Emphasis is placed on marine pollution, particularly on the toxic metal accumulation in biota.

This study has revealed the different concentrations of pollutants, low, moderately, and chronically contaminated areas from heavy metals and the consequences to aquatic ecosystem and indirectly to human health, since an increasing in the coastal developments in Peninsular Malaysia.

This study has revealed the different concentrations of pollutants, low, moderately, and chronically contaminated areas from heavy metals and the consequences to aquatic ecosystem and indirectly to human health, since an increasing in the coastal developments in Peninsular Malaysia.

Brazilian sediment quality criteria were established based on pseudo-total metal contents, which is not suitable to determine their bioavailability and the ecological risk for aquatic biota. Therefore, the geochemical speciation of five metals (Cu, Fe, Ni, Pb and Zn) was determined to assess the distribution and ecological risk of sediments in a tropical shallow reservoir from Brazil. The paper aims to discuss these issues.

A survey of metals in ten representative stations of surface sediments (0-20 cm) from Carlos Botelho (Lobo-Broa) Reservoir was conducted during the dry season in April 2014. Sediment parameters were measured in situ. The geochemical speciation of metals was carried out using the modified three-stage BCR-701 procedure (Davutluoglu et al., 2011) and compared with pseudo-total metal contents.

Contamination at S-1 and S-8 was more severe than other sampling sites, especially for Cu, Ni, Pb and Zn. Metals such as Cu, Ni and Zn occasionally may be associated with adverse biological effects based on the comparison with sediment quality guidelines. The risk assessment code suggests no risk for Fe and low risk for Cu and Ni.

Geochemical speciation of metals could be useful in developing effective management strategies to control metal pollution in the Lobo-Broa Reservoir. Substantial amounts of Pb (classified as medium risk) were bound to humic substances and/or insoluble metal sulfides, and could pose serious risk to the benthic community through the food chain. Zinc at S-1, S-3 and S-8 showed high risk, indicating that an appreciable portion of Zn could be available to aquatic biota.

The Gangetic delta, sustaining the Sundarbans mangrove forest at the apex of the Bay of Bengal is recognized as one of the most diversified and productive ecosystems in the Indian subcontinent. The deltaic lobe is unique for its wilderness, mangrove gene pool and tiger habitat. However, due to intense industrial activities in the upstream zone, and several anthropogenic factors, the aquatic phase in the western part of the deltaic complex is exposed to pollution from domestic sewage and industrial effluents leading to serious impacts on biota. The presence of Haldia port-cum-industrial complex in the upstream region of the lower Gangetic delta (adjacent to western sector of Indian Sundarbans) has accelerated the pollution problem to a much greater dimension. The organic and inorganic wastes released from industries and urban units contain substantial concentrations of heavy metals. The present article aims to highlight the level of selective heavy metals (zinc, copper, and lead) in the water and muscle of a commercially important shellfish species (Penaeus monodon, commonly known as tiger prawn) collected from two sectors (western and central) in the Indian Sundarbans. Heavy metals are accumulated in the prawn muscle in the following order – zinc > copper > lead – which is similar to the order in the ambient estuarine water. Significant spatial variations of heavy metal concentrations in estuarine water and prawn muscle were observed between the selected sectors, which reflect the adverse impact of intense industrialization, unplanned tourism, and rapid urbanization on the mangrove ecosystem and its biotic community, particularly in the western Indian Sundarbans.

The study investigated the heavy metal flux around the vicinity of a steel recycling factory using passive biomonitoring technique with several pollution indices to assess the quality of the ambient environment.

The vegetation around the facility was identified, and the most abundant species were selected for analysis. The collected samples were dried, milled, sieved and analyzed for elemental composition using energy dispersive X-ray fluorescence (ED-XRF). Pollution indices were used to quantitatively assess the data.

Results show that maximum contamination occurs at the vicinity of factory. Generally, the deterioration of the ambient air around the vicinity of the steel recycling plant decreases with increasing distance from the steel recycling plant. However, for the radius considered in this study – 1 km, the ambient air at 1 km of the steel recycling facility is quickly deteriorating, and there is an urgent need for measures to mitigate the air quality impact of the steel recycling facility.

The study shows that the metal recycling process emits high levels of heavy metals to the environment, and there is an urgent need for personal protective equipment for the human population working in and around the close proximity of the recycling plant.

Pakistan is an agricultural country having the world's largest canal irrigation system. Indus basin that covers 70 percent of irrigated area for crop production is the major source of water in the country. Owing to rapid increase in population and uncertain environmental conditions, this water is not adequate to cope with the crop water requirement and needs additional means to provide extra water for agricultural purposes. The main source of irrigation is canal and ground water but the quality of ground water is so poor for the sustainability of agriculture system. To cope with the present demand, use of municipal sewage water that consists of domestic liquid waste, as well as industrial effluents, is becoming a common practice. The present study aims to reflect the hazardous effects of sewage water on the environment, with the main focus on heavy metals and chemical composition of soil and vegetables.

Industrial effluent was collected from one ghee mill, one flour mill, three textile industries and three hosieries located in Faisalabad, an industrial city of Pakistan highly affected with water pollution. All water samples were analyzed for pH, EC, SAR and RSC. Water analysis was also carried out for various nutrients and heavy metals (K⁺¹, P²⁺, Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺ and Pb²⁺). Soil samples from various depths (0‐15, 15‐30, 30‐60, 60‐90 and 90‐120 cm) were taken to analyze for EC, pH, SAR, Na⁺¹, SO₄, K⁺¹, P²⁺, Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺ and Pb²⁺ after irrigation with canal water and sewage water. Cadmium, lead and copper concentration was determined in various vegetables grown in areas irrigated with canal water and industrial effluents to determine their final concentration in the final product ultimately affecting the human health.

Although the sewage water is a source of many nutrients, it also includes a significant amount of heavy metals like Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺, Pb²⁺ and pathogens. Extensive use of this effluent for irrigation purpose has resulted in an upsurge of such metals in soils and various crops, which ultimately resulted in clinical problems in human beings.

The present study reflects the composition of sewage water and heavy metal accumulation in soil, as well as crops. It further highlights the different potential hazards to humans due to these contaminants.