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"Saguling reservoir has recently been facing to several serious problems such as water qualitydegradation due to organic matter contamination, heavy metal, pesticides and other micropollutant materials.... "

"The Jakarta bay and and lada bay have been known as a polluted environment. The dominant polluted is heavy metals such as Pb, Cd, Cr ang hg...."

"Efisiensi divais solar sel merupakan salah satu parameter yang menunjukkan unjuk kerja divais tersebut. Salah satu parameter yang berpengaruh terhadap efisiensi divais solar sel yaitu disain top contact metal. Disain top contact metal akan berpengaruh terhadap power loss yang diakibatkan oleh shadowing loss yang besarnya hingga 13,1%[1]. Berbagai riset telah dilakukan untuk mendapatkan disain Top contact metal dengan shadowing loss yang sekecil mungkin. Carbon nanotube (CNT) memiliki potensi untuk dijadikan sebagai Top contact metal. Pada riset ini dilakukan perancangan, perhitungan dan simulasi penggunaan CNT (3,3) sebagai top contact metal. Simulasi dilakukan dengan menggunakan perangkat lunak MatLab 7.1. Berdasarkan analisis yang dilakukan, CNT berpotensi untuk dijadikan sebagai top contact metal pada silikon solar sel jika di-doping dengan maksimum doping sebesar 3.25 10¹¹ /cm³. Pemilihan CNT (3,3) didasarkan pada work function yang dimilikinya. Berdasarkan hasil perhitungan diperoleh hasil bahwa dengan penggunaan CNT (3,3), shadowing loss yang dihasilkan yaitu 0%. Hal ini berarti shadowing loss dapat dihilangkan sebesar 13.1%. Dengan demikian penggunaan CNT(3,3) dapat meningkatkan efisiensi solar sel sampai dengan 13,1%.

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Solar cells efficiency is one of the parameter which show the performance of solar cell. The efficiency of solar cell is affected by top contact metal design. Shadowing loss as the effect of top contact metal design can reduce solar cell efficiency until 13.1%[1]. Many research had been conduct to reduce the shadowing loss as much as possible. CNT (3,3) as a material with metallic properties is potential to be applied as top contact metal.

This research is conduct to design, calculate, and simulate the potential of CNT as top contact metal to reduce shadowing loss. Simulation is ran by MatLab 7.1.

Based on analysis, CNT is potential to act as top metal contact at silicon solar cell with maximum doping at 3.25 10¹¹ /cm³. CNT (3,3) is choosed based on its work function.

From calculation, the use of CNT (3,3) resulted shadowing loss 0%. That means shadowing loss can be reduced up to 13.1% or increasing the efficiency of solar cell up to 13.1%."

"Influence of Zr element at U-Zr alloys and it interaction with the Al metal to phase forming. Have been done research of Zr element addition influence at U-Zr alloys and its interaction with the composition of 2,6,10,14 and 55% w Zr respectively are added by Al metal with the comparison of U-Zr and Al metal as one compared to half...."

"Applied Metal Forming: Including FEM Analysis describes metal forming theory and how experimental techniques can be used to study metal forming operations with great accuracy. For each primary class of processes, such as forging, rolling, extrusion, wiredrawing, and sheet-metal forming, it explains how finite element analysis (FEA) can be applied with great precision to characterize the forming conditions and in this way optimize the processes. FEA has made it possible to build realistic FEM models of most metal forming processes, including complex three dimensional forming operations, in which complex products are shaped by complex dies. Thus, using FEA, it is now possible to visualize any metal forming process and to study strain, stress, and other forming conditions inside the parts being manufactured as they develop throughout the process. Henry S. Valberg is a professor in the Department of Engineering Science and Materials at the Norwegian University of Science and Technology(NTNU). He began his professional career as a metallurgist at the Royal Norwegian Air Force (LFK), and continued it at A/S NorskJernverk, Mo i Rana, and then as a research scientist at SINTEF, Division of Materials and Processes, before joining the Norwegian Institute of Technology (NTH) as a senior lecturer in 1984 and full professor in 1994. He was a visiting professor at Denmark’s Technical Universityin 1997–1998. Professor Valberg’s main fields of research are materials, metal forming, experimental deformation analysis, and FEA. His work covers all the main metal forming processes, including forging, rolling, extrusion, drawing, and sheet-metal forming. He is the authorof more than 60 refereed journal articles and has supervised numerous graduate students. Professor Valberg is currently a research manager in a project run by three Norwegian forging companies."

"ABSTRAK Dalam Penelitian sebelumnya tanin banyak digunakan sebagai pengompleks ion-ion logam. Pembentukan kompleks asam Iemah tannin dipengaruhi kondisi Iingkungan seperti pH larutan. Pada penelitian ini dipelajari karakteristik tanin, kompleksnya clan kestabilannya pada beberapa pH secara spektrofotometri.Karakteristik kompleks tanin dipelajari dengan titrasi spektrofotometri. Untuk mempelajari karakter kompleks tanin sebelumnya dilakukan karakterisasi gugus fungsi tanin dengan spektroskopi IR, uv, clan mereaksikan tanin dengan ion Fe 2+ . Ligan makromolekul tanin dititrasi penambahan ion Fe2 . Ligan makromolekul tanin dititrasi dengan ion logam Cu(II) dan Co(II) pada pH yang sama dan secara kontinyu diukur serapannya..Tetapan kestabilan kondisional kompleks dipelajari dengan persamaan Scatchard dengan parameter v dan v/M yang telah digunakan dalam penentuan tetapan kestabilan kondisional kompleks makromolekul asam humat dan protein.Analisis tanin dengan IR dan reaksinya dengan ion Fe21 menunjukkan bahwa tanin aldrich yang digunakan dalam percobaan termasuk golongan pirogallol atau tanin terhidrolisis yang mempunyai gugus aktif fenol dan karboksilat. Spektra uv tanin menunjukkan serapan yang meningkat dengan naiknya pH. Spektra komplekS tidak berbeda secara signifikan denganspektra ligan bebasnya. Penurunan serapan karena penambahan ion logam setelah koreksi pengenceran sangat kecil clan kurva titrasi yang diperoleh sangat landai.Secara keseluruhan nilai tetapan kestabilan kondisional kompleks (K') tanin turun pada pH yang lebih tinggi. Berdasarkan teori dan penelitian sebelumnya dengan metoda lain maka hasil ini bertolak belakang sehingga penggunaan metoda spektrofotometri uv untuk menentukan tetapan kestabilan kondisional kompleks harus dipertimbangkan kembali."