Protective System for Magnesium Melt

2005 ◽  
Vol 488-489 ◽  
pp. 85-88 ◽  
Author(s):  
A. Karger ◽  
Friedrich Wilhelm Bach ◽  
C. Pelz
Keyword(s):  
The Other ◽  
Protective Atmosphere ◽  
Ministry Of Education ◽  
Molten Bath ◽  
New Methods ◽  
Environmental Friendly ◽  
Protective System ◽  
Molten Magnesium ◽  
Magnesium Melt ◽  
Gas Expansion

The environmentally friendly alternatives are being examined by an R&D group funded by German Federal Ministry of Education and Research. The research goals of this group are to analyze the potential of known environmental friendly gases to serve as protective atmosphere, and also to develop and to evaluate new methods for protecting the surface of magnesium melts. One possible alternative is covering the magnesium melt with CO2-snow, which is deposited on the molten bath and decreases the surface temperature of the melt. On the other hand gas expansion is the result of the sublimation of the CO2-snow which displaces any oxygen at the surface of the molten magnesium.

Ultrasonic Ion Pumps in Bio-Battery’s Electrolyte

2012 ◽  
Vol 463-464 ◽  
pp. 909-913
Author(s):  
Ahmad Amjadi ◽  
Afsoon Ebrahimi ◽  
Arefe Sherafati ◽  
Narges Khalilgharibi ◽  
Mani Karimkhan Zand ◽  
...  
Keyword(s):  
Electricity Generation ◽  
Standing Waves ◽  
The Other ◽  
Common Method ◽  
Ion Pumps ◽  
Wide Spread ◽  
New Methods ◽  
Environmental Friendly ◽  
Biological Sources ◽  
Near Future

Bio-batteries are environmental friendly electricity generation devices that utilize energy from biological sources , like glucose[1][2]. It consists of an anode with digesting enzymes and a cathode comprising oxygen-reducing enzymes. Immobilizing enzymes is a considerable issue in these kinds of devices. In this article, we propose two new methods for immobilizing and shifting particles likewise enzymes used in bio-batteries towards the anode or cathode end. Our experiments illustrate how tiny particles could be trapped in the nodes of the ultrasonic standing waves and by two methods of displacing the nodes, we can transfer the particles towards a desired location. First method is based on sweeping the frequency of the operation to the higher frequency and the second is based on changing the circuit phase. The above-mentioned methods can be used instead of the other common method in which certain polymers is applied for this purpose. Using these polymers are not economically commodious and makes bio-batteries too expensive[1]. We hope suggested methods lead to wide spread production of bio-batteries in near future and in more efficient ways than they are currently being produced

A New Low GWP Protective Atmosphere Containing HFC-152a for Molten Magnesium against Ignition

2005 ◽  
Vol 488-489 ◽  
pp. 73-76 ◽  
Author(s):  
Yi-wen Zeng ◽  
Li Ming Peng ◽  
Xie Min Mao ◽  
Xiao Qing Zeng ◽  
Wen Jiang Ding
Keyword(s):  
Electron Microscopy ◽  
Surface Film ◽  
Protective Atmosphere ◽  
X Ray Diffraction ◽  
Sulphur Hexafluoride ◽  
X Ray ◽  
Molten Magnesium ◽  
Magnesium Melt ◽  
Hfc 152A ◽  
Scanning Electron

Sulphur hexafluoride (SF6) is widely used by the magnesium industry as a protective atmosphere. It has been demonstrated that SF6 prevents molten magnesium from further oxidation by reacting with magnesium to make the surface film on the magnesium melt denser. However, due to its high greenhouse effect (GWP=23900), the alternatives of SF6 must be sought. In this paper, 1,1-difluoroethane (commercially named HFC-152a), whose GWP value is only 140 and far lower than that of SF6, was tested to check its capacity of ignition-proof and further-oxidation-proof. Similar to SF6, the melt’s surface film formed in the protective atmosphere containing HFC-152a has a shiny metallic appearance. The surface film’s microstructure has been characterized with X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD’s results showed that the film contains only MgO and MgF2 phases while SEM showed their morphologies are uniform.

scholarly journals Error Analysis for a Noisy Lacunary Cubic Spline Interpolation and a Simple Noisy Cubic Spline Quasi Interpolation

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Feng-Gong Lang ◽  
Xiao-Ping Xu
Keyword(s):  
Error Analysis ◽  
Error Bounds ◽  
Interpolation Method ◽  
Spline Interpolation ◽  
Cubic Spline ◽  
The Other ◽  
Cubic Spline Interpolation ◽  
Numerical Tests ◽  
New Methods ◽  
Noisy Function

We mainly present the error analysis for two new cubic spline based methods; one is a lacunary interpolation method and the other is a very simple quasi interpolation method. The new methods are able to reconstruct a function and its first two derivatives from noisy function data. The explicit error bounds for the methods are given and proved. Numerical tests and comparisons are performed. Numerical results verify the efficiency of our methods.

scholarly journals CLT at the Higher Secondary Level in Bangladesh: Theory and Practice

IIUC Studies ◽  
2016 ◽  
Vol 12 ◽  
pp. 71-86
Author(s):  
Md Mohib Ullah
Keyword(s):  
Foreign Language ◽  
Teaching And Learning ◽  
Language Teaching ◽  
Secondary Level ◽  
Communicative Language Teaching ◽  
Theory And Practice ◽  
Ministry Of Education ◽  
Efl Context ◽  
New Methods ◽  
Real Picture

With the progress of time, the aim of teaching and learning English as a Second Language (ESL) or English as a Foreign Language (EFL) changed, and so did the approaches and methods in language teaching. Different methods and approaches emerged and were replaced, influenced or contributed to the emergence of new methods. It is widely acknowledged that one umbrella approach to language teaching that has become the accepted "norm" in this field is the Communicative Language Teaching Approach. This study deals with the theories and practices of CLT at the Higher Secondary level in Bangladesh. Realizing the significance of CLT, The Ministry of Education in Bangladesh made groundbreaking attempts to implement CLT in the new context and also brought some changes in the curriculum in 1990s. Along with attempting to provide a real picture of how CLT is practiced and utilized in an ESL/EFL context, this study focuses on the Practice of CLT approach in Bangladesh. Moreover, this study intends to propose some propositions to be implemented for better practice of CLT in ESL/EFL contexts.IIUC Studies Vol.12 December 2015: 71-86

Mechanical Properties of Jute/PLA Injection Molded Products-All Natural Composites

2011 ◽  
Author(s):  
Masuo Murakami ◽  
Yuqiu Yang ◽  
Hiroyuki Hamada
Keyword(s):  
Mechanical Properties ◽  
Injection Molding ◽  
Density Measurement ◽  
The Other ◽  
Jute Fiber ◽  
Poly Lactic Acid ◽  
Thermoplastic Polymer ◽  
Environmental Friendly ◽  
Molding Condition ◽  
Natural Composites

Natural composites have been important materials system due to preservation of earth environments. Natural fibers such as jute, hemp, bagasse and so on are very good candidate of natural composites as reinforcements. On the other hand regarding matrix parts thermosetting polymer and thermoplastic polymer deriver form petrochemical products are not environmental friendly material, even if thermoplastic polymer can be recycled. In order to create fully environmental friendly material (FEFM) biodegradable polymer which can be deriver from natural resources is needed. Therefore poly(lactic acid) (PLA) polymer is very good material for the FEFM. However, PLA is very brittle polymer, so that polymer chemists have been made the efforts to make tough PLA. In this paper Jute/PLA composites was fabricated by injection moldings and mechanical properties were measured. It is believable that industries will have much attention to FEFM, so that injection molding was adopted to fabricate the composites. Long fiber pellet pultrusion technique was adopted to prepare jute fiber-PLA pellet (Jute/PLA). Because it is a new method which is able to fabricate composite pellets with relative long length fibers for injection molding process, where, jute yarns were continuously pulled and coated with PLA resin. Here two kinds of PLA materials were used including the one with mold releasing agent and the other is without it. After pass through a heated die whereby PLA resin impregnates into the jute yarns and sufficient cooling, the impregnated jute yarns were cut into pellets. Then Jute/PLA pellets were fed into injection machine to make dumbbell shape specimens. In current study, the effects of temperature of heat die i.e. impregnation temperature and the kind of PLA were focused to get optimum molding condition. The volume fractions of jute fiber in pellet were measured by several measuring method including image analyzing, density measurement and dissolution methods. And the mechanical property were investigated by tensile and Izod testing. It is found that 250 degree is much suitable for Jute/PLA long fiber pultrusion process. Additionally the jute fibers seem much effective to increase the tensile modulus and the Izod strength. That is to say, the addition of Jute fiber in PLA, the brittle property can be improved.

Gender and National Differences in Attitudes toward Same-Gender Touch

1994 ◽  
Vol 78 (3) ◽  
pp. 1027-1034 ◽  
Author(s):  
Frank N. Willis ◽  
Vicki A. Rawdon
Keyword(s):  
Cultural Differences ◽  
Female Students ◽  
Cross Cultural ◽  
The Other ◽  
Male And Female ◽  
New Methods ◽  
Cross Cultural Differences ◽  
National Differences ◽  
The Us ◽  
Same Gender

Women have been reported to be more positive about same-gender touch, but cross-cultural information about this touch is limited. Male and female students from Chile (n = 26), Spain (n = 61), Malaysia (n = 32), and the US (n = 77) completed a same-gender touch scale. As in past studies, US women had more positive scores than US men. Malaysians had more negative scores than the other three groups. Spanish and US students had more positive scores than Chilean students. National differences in attitudes toward particular types of touch were also noted. The need for new methods for examining cross-cultural differences in touch was discussed.

scholarly journals EFL TEACHERS� UNDERSTANDING IN DEVELOPING LESSON PLAN

2017 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Annisa Putri
Keyword(s):  
Data Collection ◽  
Lesson Plan ◽  
The Other ◽  
Learning Assessment ◽  
Ministry Of Education ◽  
Plan Analysis ◽  
Other Hand ◽  
Efl Teachers ◽  
Scientific Approach ◽  
State Learning

This research attempts to find out EFL teachers� understanding of lesson plan and the development along with problems the teachers faced in developing lesson plan. The researcher used two data collection techniques; interview and analyzing the lesson plan developed by four EFL teachers. The interview results revealed that all participants understand about the lesson plan as well as its development and understand about the elements that should be included as parts of lesson plan, but, unfortunately, the teachers could not understand the system of learning assessment. They thought that it is too complicated because they should provide one system of learning assessment along with the rubric of assessment. On the other hand, the result of lesson plan analysis showed that all participants understand how to develop lesson plan by stating all elements of lesson plan in accordance with the requirements stated in the Regulation of Ministry of Education and Culture No. 103 in 2014. The problems found are when the teachers did not state learning purposes, even two of the teachers stated that learning indicator is similar with learning purposes. Another problem is found when they did not include the assessment rubric. Then, the other problem is found when they were asked about the implementation of scientific approach. Scientific approach is a new thing for them to be applied as the approach consists of observing, questioning, associating, collecting, and communicating.Keywords: lesson plan, lesson plan development, 2013 curriculum

scholarly journals BIOLOGICAL CONTROL IN LEAF-CUTTING ANTS, Atta sexdens (HYMENOPTERA: FORMICIDAE), USING PATHOGENIC FUNGI

2021 ◽  
Vol 45 ◽  
Author(s):  
Tarcísio Marcos Macedo Mota Filho ◽  
Luis Eduardo Pontes Stefanelli ◽  
Roberto da Silva Camargo ◽  
Carlos Alberto Oliveira de Matos ◽  
Luiz Carlos Forti
Keyword(s):  
Biological Control ◽  
Chemical Control ◽  
Pathogenic Fungi ◽  
Behavioral Changes ◽  
The Other ◽  
Fungus Garden ◽  
Atta Sexdens ◽  
Main Method ◽  
New Methods ◽  
Leaf Cutting

ABSTRACT Chemical control using toxic baits containing the active ingredient sulfluramid at 0.3% (w/w) is the main method for controlling leaf-cutting ants of the genera Atta and Acromyrmex. However, since 2009, when sulfluramid was included in Annex B of the Stockholm Convention on Persistent Organic Pollutants, there has been an intense search for new methods that are efficient in controlling these insects. Among said new methods, biological control using pathogenic fungi has shown promising results in laboratory conditions. The objective of this study, given the context presented, was to assess the potential of the fungi Beauveria bassiana and Trichoderma harzianum in controlling Atta sexdens. Colonies of A. sexdens were exposed to the fungi by means of formulated baits provided in a foraging chamber, or of suspensions sprayed on the fungus garden, and had their behavioral changes recorded for 21 days. For both formulations, concentrations of 10 and 20% (w/w) of the fungi being studied were used. The results allowed concluding that baits containing 10 and 20% (w/w) of the fungi B. bassiana and T. harzianum were not efficient in controlling colonies of A sexdens. On the other hand, spraying suspensions of 20% (w/w) of B. bassiana and 10% and 20% (w/w) of T. harzianum was efficient and resulted in 100% mortality of the colonies 11, 9 and 7 days after application, respectively. These findings indicate that the fungi B. bassiana and T. harzianum are promising as agents for the control of A. sexdens colonies, when sprayed on the fungus garden, although there are still some challenges as to their use related to the development of technologies for the application of the pathogen.

scholarly journals Pengolahan Limbah Kulit Durian dan Baterai Bekas Menjadi Salah Satu Sumber Energi Listrik yang Ramah Lingkungan

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Muhammad Gifron ◽  
Nelmi Agustina ◽  
Doris Wela
Keyword(s):  
Alternative Energy ◽  
Organic Waste ◽  
Plastic Waste ◽  
The Other ◽  
Basic Material ◽  
The Sun ◽  
Environmental Friendly ◽  
Waste Rubber ◽  
The World ◽  
Parallel Circuit

Abstrak. Seiring dengan bertambahnya jumlah penduduk dunia, selalu diiringi oleh masalah limbah yang berasal dari sampah, baik sampah organik maupun non organik. Berbagai usaha untuk mengatasi masalah limbah tersebut secara berkesinambungan terus dilakukan , baik itu sampah-sampah anorganik seperti, berbahan plastik, karet dan lain-lain. Bisa dimanfaatkan kembali melalui daur ulang menjadi barang-barang kebutuhan harian. Sedangkan untuk sampah organik selain dimanfaatkan untuk pupuk, juga dapat digunakan sebagai bahan dasar pengisi baterai untuk menghasilkan energi alternatif yang ramah lingkungan. Terkhususnya untuk pemanfaatan limbah organik dalam pembuatan baterai telah dilakukan dengan beda potensial tertinggi yang dihasilkan adalah 1,67 volt. Dalam penelitian ini dilakukan modifikasi massa bahan pengisi baterai yang bersumber dari kulit durian yang yang diproses khususnya melalui pengeringan menggunakan oven serta dicampur dengan asam dan ada juga kulit durian yang dijemur selama 7 hari dengan massa kulit durian 3, 5, dan 10. Beda potensial baterai tertinggi yang didapatkan adalah 10 gram yaitu sebesar 1,67 volt. Selanjutnya baterai dengan massa 10 gram difabrikasi dalam jumlah tertentu yang digunakan untuk menyalakan LED. Baterai tersebut dirangkai baik secara seri maupun paralel untuk menghasilkan beda potensial yang bervariasi. Abstract. Along with the growing number of the world populations, there always followed by troubles waste derived from trash, organic waste, and non-organic waste. Many attempts to deal with an organic waste such as plastic waste, rubber, and etc, has been continued, so those waste can be recycled and reused for daily demand. On the other hand, organic waste can be used as fertilizer, and basic material for the battery that results an environmental friendly alternative energy. Especially to utilize the organic waste, the making of battery has been done that yields highest voltage, 1.67 volts. This research aims to modify the mass filler of the battery that obtained from durian skin which is processed by mixing it with acid and drying it using oven, there also other technique by drying the durian skin under the sun for about 7 days which varied masses of 3 gram, 5 gram, and 10 gram. The highest voltage that obtained is 1.67 volt using 10 gram durian skin. Further, the battery with 10 grams durian skin is then fabricated in a specified number to light up the LED. This battery placed either in serial or parallel circuit to obtain varied voltage.

scholarly journals Consumers Purchase Behavior Toward Eco-Labelling

2021 ◽  
Author(s):  
Madiha Tahir
Keyword(s):  
Social Responsibility ◽  
Environmental Effects ◽  
The Other ◽  
Purchase Behavior ◽  
Environmental Responsibility ◽  
Ethical Responsibility ◽  
Purchasing Behavior ◽  
Buying Behavior ◽  
Environmental Friendly ◽  
The Relationship

The primary goal of Eco-labels is to promote the knowledge of consumers about positive environmental effects of products and to guide them toward purchasing environmental friendly products. The purpose of the study is to understand fashion consumers' purchasing behavior toward eco-labelling with respect to four factors: the current fashion system, environmental responsibility, ethical responsibility, and social responsibility. The relationship between these four factors in conjunction with eco-labelling and purchase behavior was tested and analyzed. The results proved that eco-labels did influence consumers' buying behavior. Eco-label help consumers to make their decision faster, distinguish those products that they want to buy from the other ordinary products.

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