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Abstrak :
The SMST Conferences focus on real-world issues and applications of shape memory materials. This volume includes more than 75 edited technical papers and is an excellent reference on the latest technical advances, industrial applications, and current state-of-the-art in shape memory and superelastic technologies.

Abstrak :
The SMST Conferences are a series of shape memory industry conferences focusing on real-world issues and applications of shape memory materials. Each volume of the proceedings contains over 100 technical papers and is an excellent reference on the current state-of-the-art in the shape memory and superelastic industry. Topics covered include Medical and Dental Applications, Biocompatibility, Corrosion, Actuators, Connectors, Alloy Processing, Manufacturing Issues, Laser Processing, Design, Finite Element Analysis, and Shape Memory Thin Films.

Abstrak :
The SMST Conferences focus on real-world issues and applications of shape memory materials. This volume includes more than 100 edited technical papers and is an excellent reference on the latest technical advances, industrial applications, and current state of-the-art in shape memory and superelastic technologies.

Abstrak :
Edited by B. Berg, M.R. Mitchell, J. Proft Audience Engineers and researches involved in the application and study of shape memory and superelastic technologies.

Abstrak :
The SMST Conferences are a series of shape memory industry conferences focusing on real-world issues and applications of shape memory materials. Each volume of the proceedings contains over 100 technical papers and is an excellent reference on the current state-of-the-art in the shape memory and superelastic industry. Topics covered include medical and dental applications, biocompatibility, corrosion, actuators, connectors, alloy processing, manufacturing issues, laser processing, design, finite element analysis, and shape memory thin films.

Abstrak :
Metilamina yang disintesis dari metanol dan amoniak diteliti pada studi ini menggunakan katalis garam parsial kalium heteropoli (Cs3-xHxPW12O40 disingkat KPW). KPW dipreparasi dari asam heteropoli dan kalium karbonat dengan metode pertukaran ion. Reaksi dilakukan pada 600~800K dan tekanan atmosfir menggunakan reaktor alir kontinyu pada W/F=0,1~0,9g-kat.mnt./cc. Analisis konsentrasi produk dan reaktan menggunakan gas kromatografi sedangkan karakterisasi struktur katalis menggunakan XRD (X-ray diffraction) dan adsorbsi isothermal untuk menentukan ukuran pori katalis Hasil penelitian menunjukkan bahwa pertukaran ion H dengan K untuk membentuk garam kalium heteropoli menyebabkan perubahan interstisial space yang teramati dengan berubahnya lattice constant dari kristal katalis. Ukuran pori yang lebih kecil dari Trimetilamina (TMA) akan tetapi lebih besar dari Monometilamina (MMA) dan Dimetilamina (DMA) menyebabkan TMA menjadi tidak diproduksi. Kristal KPW bersifat rigid sehingga pori yang terbentuk tidak berubah sepanjang reaksi, sebaliknya kristal (NH4)3PW12O40 tidak rigid dan ukuran pori mudah berubah tergantung dari ukuran metilamina yang teradsorbsi sehingga katalis ini menjadi tidak selektif terhadap metilamina yang berukuran kecil.

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Role of K3-xHxPW12O40 as a Catalyst in Selective Catalysis of Methylamine Synthesis from Ammonia and Methanol. Synthesize of methylamine from methanol and ammonia was studied in this research work using a partially potassium heteropoly salt (K3-xHxPW12O40 abbreviated as KPW) as a catalyst. KPW was prepared from heteropoly salt and potassium carbonate by using ion exchange method. The reaction was conducted at 600 ~ 800K and at the atmospheric pressure. Reactor used was a continue flow reactor with W/F=0,1~0,9g-kat.mnt./cc. Concentration of reactants and products were analyzed by gas chromathography while catalyst structure was observed by XRD (X-ray diffraction). Isothermal adsorption method was used for determining catalyst pore size. The result showed that ion exchange between H ion in zeolit with K ion produced potassium heteropoly salt that caused the change of interstitial space. The change of interstitial space was observed by the change of the lattice constant of the catalyst crystal. Trimethylamine(TMA) has molecule size smaller than catalyst pore size but bigger than molecular size of Dimethylamine (DMA) and Monimethylamine (MMA). This phenomenon caused the suppression of TMA formation. KPW has a rigid crystal structure and stabil during reaction. On the other hand, crystal structure of a non selective catalyst (NH4)3PW12O40 was not rigid and its pore size is easy to change depending on the product molecule size.

Abstrak :
Mikroplastik merupakan plastik berukuran <5 mm. Dapat terbentuk secara primer (sengaja diiproduksi) dan sekunder (hasil degradasi). Penggunaan Personal Care Product (PCP) dan bahan-bahan pembersih rumah tangga menjadi jalur masuknya mikroplastik ke IPAL. Sampel air IPAL diambil dengan metode sampel komposit. Metodologi perhitungan kelimpahan pada sampel menggunakan mikroskop cahaya binokuler (visual), identifikasi jenis polimer menggunakan FTIR dan identifikasi ukuran mikroplastik menggunakan software J-Image. Kelimpahan rata-rata mikroplastik pada penelitian ini mencapai 8×103 MP/L. Penyisihan mikroplastik mencapai 77%. Hasil identifikasi karakteristik ditemukan bentuk mikroplastik fragment (57.6%), film (14.7%), beads (12.7%), foam (9.2%), dan fiber (5.8%). Warna mikroplastik yang teridentifikasi ialah biru (36.3%), hitam (35.1%), merah (18.2%), kuning (8.6%), dan transparan (1.8%). Persebaran ukuran mikroplastik pada IPALD terbagi menjadi terkecil <0.3 mm (80%), 0.3 – 0.5 mm (2%), 0.5 – 1 mm (4%), dan >1 mm (14%). Selannjutnya jenis polimer yang ditemukan pada IPALD tersebar dari Polyvinyl Formal, Polyvinyl butyral, Polycarbonate (PC) dan Poly (butylene terephthalate) (PBT), Polyester, Polyvinyl Chloride, Polyarylate, dan Tetrafluoroethylene-Hexa-fluoro-propylene (FEP). Hasil pengujian korelasi menunjukan hubungan yang kuat dan signifikan secara statistik untuk TSS terhadap Mikroplastik. Sedangkan hubungan lemah dan tidak signifikansi secara statistik untuk parameter VSS terhadap Mikroplastik di dalam IPAL. ......Microplastics are plastics <5 mm in size. They can be primary (intentionally produced) and secondary (degradation). Its presence is difficult to detect and the potential dangers are still unknown, making it an emerging contaminant for humans and the environment. The use of Personal Care Products (PCP) and household cleaning materials is a pathway for microplastics to enter WWTP. WWTP water samples were taken using the composite sample method. The methodology for calculating the abundance of samples using binocular light microscopy (visual), identification of polymer types using FTIR and identification of microplastic size using J-Image software. The average abundance of microplastics in this study reached 8×10^3 MP/L. The removal of microplastics reached 77%. The results of the identification of characteristics found the form of microplastic fragments (57.6%), films (14.7%), beads (12.7%), foam (9.2%), and fiber (5.8%). The identified microplastic colors are blue (36.3%), black (35.1%), red (18.2%), yellow (8.6%), and transparent (1.8%). The size distribution of microplastics in WWTP is divided into the smallest <0.3 mm (80%), 0.3 - 0.5 mm (2%), 0.5 - 1 mm (4%), and >1 mm (14%). Furthermore, the types of polymers found in the WWTP were distributed from Polyvinyl Formal, Polyvinyl butyral, Polycarbonate (PC) and Poly (butylene terephthalate) (PBT), Polyester, Polyvinyl Chloride, Polyarylate, and Tetrafluoroethylene-Hexa-fluoro-propylene (FEP). The correlation test results show a strong and statistically significant relationship for TSS to Microplastics. While the relationship is weak and not statistically significant for the VSS parameter to Microplastics in the WWTP.

Abstrak :
ABSTRAK
Shape Memory Polyurethane (SMPU) telah disintesis dari penambahan polyethylene glycol (PEG-6000) sebagai segmen lunak dan 4,4'-Methylenebis (Cyclohexyl isocyanate) (HMDI) sebagai segmen keras serta 1,1,1-Trimethylol propane (TMP) sebagai chain extender. SMPU lalu ditambahkan nanopartikel Fe3O4 berukuran 20-50 nm untuk meningkatkan sifat kemagnetan. Untuk mengkonfimasi bentuk ikatan antarmuka komposit SMPU digunakan FTIR (Fourier Transform Infrared Spectroscopy). FE-SEM digunakan untuk mengetahui interface dari filler dan matriks SMPU. Konfirmasi nilai kemagnetan menggunakan VSM (vibrating sampel magnetometer) dan pengujian tarik menggunakan microtensile menunjukkan bahwa penambahan Fe3O4 dengan persentase 11 wt% menghasilkan nilai kemagnetan dan sifat mekanik tertinggi.

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ABSTRACT
Shape Memory Polyurethane (SMPU) has been synthesized by reacting polyethylene glycol (PEG-6000) as softsegment, 4,4'-Methylenebis (Cyclohexyl isocyanate) (HMDI) as hardsegment and 1,1,1-Trimethylol propane (TMP) as chain extender. SMPU was added by Fe3O4 as filler to provide magnetical property. Magnetite which had confirmed by Scanning Elctron Magnetic (SEM) have size 20-50 nm. Functional group was investigated by FTIR (Fourier Transform Infrared Spectroscopy). The magnetic behavior of the nanocomposites was observed by vibrating sample margnetometer (VSM). FE-SEM is used to acknowledge interface between filler and Shape Memory Polyurethane (SMPU) matrix. Mechanical properties tested by microtensile testing showed adding 11% Fe3O4 obtaining magnetic and nanocomposites SMPU resulted in improved materials with higher magnetical and mechanical properties.

Abstrak :
ABSTRAK
Pengembangan phase change material PCM sebagai media penyimpan termal pada aplikasi bangunan semakin lama semakin meningkat karena mencegah terjadinya pemborosan energi. Akan tetapi dalam aplikasinya, PCM memiliki dua kekurangan utama yakni nilai konduktivitas termal yang rendah dan besarnya penyusutan volume material. Pembentukan shape-stabilized PCM SSPCM dengan penambahan nanopartikel terbukti mampu mencegah kebocoran pada saat perubahan fasa dan meningkatkan nilai konduktivitas termal. Pada penelitian ini, dibentuk SSPCM menggunakan Beeswax sebagai bahan dasar karena memiliki nilai kalor laten yang besar dan Multi-walled carbon nanotubes MWCNT digunakan sebagai bahan pendukung karena nilai konduktivitas termalnya yang tinggi. Terdapat tiga jenis CNT yang dibedakan berdasarkan metode perlakuannya: CNT murni P-CNT , ball milled CNT B-CNT , dan acid treated CNT A-CNT . Komposit Beeswax/CNT divariasikan dalam persentase massa CNT 5 wt. dan 20 wt. . Sampel komposit diuji perubahan struktur dan sifat termalnya yang meliputi kalor laten peleburan, kalor laten pembekuan, titik leleh, titik beku, kalor jenis, konduktivitas termal, dan kestabilan termal. Berdasarkan hasil uji, nilai konduktivitas termal komposit Beeswax/A-CNT meningkat hingga 132 dan tidak menunjukkan perubahan fasa ketika dipanaskan melebihi titik lelehnya.

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ABSTRACT
Phase change material PCM development as thermal energy storage for building envelope is promising for energy utilization. However, there are two major drawbacks on PCM application which are low thermal conductivity and high volume reduction due to phase change transition. This research objective is to develop a shape stabilized phase change material SSPCM as composite which able to prevent leakage during the transition from solid to liquid. Beeswax was being used as PCM because of its high latent heat and Multi walled carbon nanotubes MWCNT as supporting material with high thermal conductivity. There are three types of CNT applied in this research pristine CNT P CNT , ball milled CNT B CNT and acid treated CNT A CNT . Beeswax CNT composite is variated on the mass ratio 5 wt. and 20 wt. . Composite samples were tested from structure modification and thermal performance including latent heat, sensible heat, melting point, solidifying point, thermal conductivity and thermal cycle test. Results show that thermal conductivity of composite increased by 132 and there was no significant phase transition on its melting or solidifying temperature.