scholarly journals Selenite Removal from Water

2020 ◽  
Vol 2 (1) ◽  
pp. 23
Author(s):  
Kyriaki Kalaitzidou ◽  
Andreas‐Arsenios Nikoletopoulos ◽  
Loukas Bakouros ◽  
Anastasios Zouboulis ◽  
Manassis Mitrakas

The present study aims at comparing the two most promising water treatment technologies for selenium removal. A techno‐economical comparison of Se(IV) uptake between the laboratory synthesized iron oxy hydroxide (FeOOH/2.5) with the highest positive surface density of 3.25 mmol [OH−]/g and adsorption capacity 4.3 μg Se(IV)/mg FeOOH/2.5 at pH 7, and coagulation/precipitation with the use of Fe(III) presenting an uptake capacity 3.2 μg Se(IV)/mg Fe was attempted based on the laboratory scale results. The evaluation showed that coagulation/precipitation treatment appears to be economically advantageous in comparison to adsorption process that was applied in Rapid Small Scale Column Tests (RSSCTs) with the FeOOH/2.5. It must be pointed out that for selection of the optimum removal method, other criteria should also be considered, such as post treatment requirements, water flow, labor cost, and maintenance requirements.

2015 ◽  
Vol 47 (1) ◽  
pp. 5-17
Author(s):  
Jolanta Korycka-Skorupa

Abstract The author discuss effectiveness of cartographic presentations. The article includes opinions of cartographers regarding effectiveness, readability and efficiency of a map. It reminds the principles of map graphic design in order to verify them using examples of small-scale thematic maps. The following questions have been asked: Is the map effective? Why is the map effective? How do cartographic presentation methods affect effectiveness of the cartographic message? What else can influence effectiveness of a map? Each graphic presentation should be effective, as its purpose is to complete written word, draw the recipients’ attention, make text more readable, expose the most important information. Such a significant role of graphics results in the fact that graphic presentations (maps, diagrams) require proper preparation. Users need to have a chance to understand the graphics language in order to draw correct conclusions about the presented phenomenon. Graphics should demonstrate the most important elements, some tendencies, and directions of changes. It should generalize and present a given subject from a slightly different perspective. There are numerous examples of well-edited and poorly edited small-scale thematic maps. They include maps, which are impossible to interpret correctly. They are burdened with methodological defects and they cannot fulfill their task. Cartography practice indicates that the principles related to graphic design of cartographic presentation are frequently omitted during the process of developing small-scale thematic maps used – among others – in the press and on the Internet. The purpose of such presentations is to quickly interpret them. On such maps editors’ problems with the selection of an appropriate symbol and graphic variable (fig. 1A, 9B) are visible. Sometimes they use symbols which are not sufficiently distinguishable nor demonstrative (fig. 11), it does not increase their readability. Sometime authors try too hard to reflect presented phenomenon and therefore the map becomes more difficult to interpret (fig. 4A,B). The lack of graphic sense resulting in the lack of graphic balance and aesthetics constitutes a weak point of numerous cartographic presentations (fig. 13). Effectiveness of cartographic presentations consists of knowledge and skills of the map editor, as well as the recipients’ perception capabilities and their readiness to read and interpret maps. The qualifications of the map editor should include methodological qualifications supported by the knowledge of the principles for cartographic symbol design, as well as relevant technical qualifications, which allow to properly use the tools to edit a map. Maps facilitate the understanding of texts they accompany and they present relationships between phenomenon better than texts, appealing to the senses.


Author(s):  
Lya Aklimawati ◽  
Djoko Soemarno ◽  
Surip Mawardi

Development the competitive industries primarily small firms ought to be realized for improving economic growth of a community. Small industries have an important role especially on income equity improvement in rural areas. The objective of this study was to assess industry players motivation for developing their business in coffee processing and also to analyze factors which influence business income focused on micro and small-scale coffee industries in Bondowoso District. Survey method was used in this study for collecting primary and secondary data. A number of respondents were 25 coffee industry players who be determined by judgement sampling method. Data were analyzed by descriptive and statistic method. Multiple linear regression was used in the suspected factors that affect small industries income. The results indicated that the main motivation of industry players in initiating and developing coffee business was financial incentive. Consecutively, indicators that may explain industry player’s motivation were expectation, motive and incentive. Micro and small-scale industries income was affected by raw material, marketing reach, technology and business experience. Meanwhile, micro and small-scale industries income was not affected by labor cost and source of capital.


Author(s):  
Afodu Osagie John ◽  
Shobo Bolatito Adenike ◽  
Ayo-Bello Taofeek Ayodeji ◽  
Abasilim Chinwe Frances

Broiler birds are widely praised for its palatability and nutritious values which are mainly for meat purpose, and also serves as source of income to many households in Nigeria. The broiler industry is faced with high cost of production thereby reducing the farmers profit. The study was conducted in three Geopolitical zones in Nigeria. A multistage sampling technique was adopted for this study for the selection of 540 broilers farmers out which 392 returned a well filled questionnaire where data were extracted for the study. Data for this study were analysed using descriptive (frequency and percent) budgetary analysis and inferential (Logit regression) statistics. Factors affecting the profit level of broiler farmers were age (γ1= -0.145, p= 10%), households size (γ3= -5.477, p=10%), educational status of the farmers (γ4= 0.228, p= 5%), number of birds (γ7= 0.575, p= 5%), cost of feed (γ8= -1.022, p= 1%), cost of water (γ9= -1.277, p= 1%), cost of drugs (γ10= -1.640, p= 5%) and cost of chick (γ11= -7.104, p= 1%). Young people should be encouraged to be involved in production of broiler, since agriculture has aging population and help in employment creation. Farmers should maintain a low number of households so as to increase their profit. The farmers should have some forms of education on the production of broilers so as to enhance their profit.


2013 ◽  
Vol 21 (12) ◽  
pp. 3029-3036
Author(s):  
赵阳 ZHAO Yang ◽  
巩岩 GONG Yan
Keyword(s):  

2019 ◽  
Vol 27 (2) ◽  
pp. 1870-1887 ◽  
Author(s):  
Ali Maged ◽  
Ismael Sayed Ismael ◽  
Sherif Kharbish ◽  
Binoy Sarkar ◽  
Sirpa Peräniemi ◽  
...  

AbstractLead (Pb(II)) pollution in water poses a serious threat to human health in many parts of the world. In the past decades, research has been aimed at developing efficient and cost-effective methods to address the problem. In this study, dimethyl sulfoxide (DMSO) and potassium acetate (K-Ac) intercalated kaolinite complexes were synthesized and subsequently utilized for Pb(II) removal from water. The intercalation of kaolinite with DMSO was found to be useful for expanding the interlayer space of the clay mineral from 0.72 to 1.12 nm. Kaolinite intercalation with K-Ac (KDK) increased the interlayer space from 1.12 to 1.43 nm. The surface area of KDK was found to be more than threefold higher as compared to natural kaolinite (NK). Batch experimental results revealed that the maximum Pb(II) uptake capacity of KDK was 46.45 mg g−1 which was higher than the capacity of NK (15.52 mg g−1). Reusability studies showed that KDK could be reused for 5 cycles without substantially losing its adsorption capacity. Furthermore, fixed-bed column tests confirmed the suitability of KDK in continuous mode for Pb(II) removal. Successful application of intercalated kaolinite for Pb(II) adsorption in batch and column modes suggests its application in water treatment (especially removal of divalent metals).


2020 ◽  
Vol 37 ◽  
pp. 101473 ◽  
Author(s):  
G. Ezzati ◽  
M.G. Healy ◽  
L. Christianson ◽  
K. Daly ◽  
O. Fenton ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document