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"EPDM dan NR merupakan polimer yang tidak misibel dan kompatibel. Penambahan kompatibiliser maleat anhidrat diharapkan menghasilkan campuran yang kompatibel dengan sifat mekanik yang baik. Pencampuran EPDM dan NR dilakukan menggunakan alat two roll mill, dengan rasio EPDM/NR adalah: 100/0, 80/20, 70/30, 60/40, 50/50, dan 40/60 phr.
Tujuan dari penelitian ini adalah untuk mengetahui pengaruh rasio EPDM/NR terhadap sifat reologi, aging, termal dan swelling dari campuran EPDM/NR.
Hasil penelitian menunjukkan penambahan NR mempengaruhi torsi maksimum, waktu scorch dan waktu vulkanisasi optimum. Penambahan EPDM memberikan sifat aging, termal dan swelling lebih baik.

The blends of EPDM and NR are immiscible in nature and incompatible. Introducing maleic anhydride as a compatibilizer into the blends was expected to produce compatible blends with balanced mechanical properties.
The purpose of this research was to determine the effect of EPDM/NR ratio on the rheological, aging, thermal and swelling properties of the blends. The variation of EPDM/NR ratio were 100/0, 80/20, 70/30, 60/40, 50/50, and 40/60 phr. The blends were mixed using two roll mill.
The results showed that the addition of NR affects the maximum torque, scorch time, and optimum vulcanization time. In the blends, EPDM plays an important role in improving aging, swelling, thermal properties.
"
[Place of publication not identified]: Balai Besar Kulit, Karet, dan Plastik, 2016
530 KKP 32:1 (2016)
Artikel Jurnal  Universitas Indonesia Library
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Macosko, Christopher W.
New York: Wiley-VCH, 1994
531.113 4 MAC r
Buku Teks  Universitas Indonesia Library
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Dedi Priadi
"Pada proses pengerjaan panas logam (hot forming) perilaku mekanik material dipengaruhi oleh temperatur kecepatan proses serta kondisi kontak permukaan. Untuk mendapatkan gaya deformasi pengerjaan panas perlu diketahui rheologi bahan kondisi panas. Dalam penelitian ini dipelajari perilaku rheologi kuningan C26800 yang digunakan sebagai bahan katup tabung gas yang mana dalam pembuatannya adalah dengan tempa panas. Dari hasil penelitian didapat bahwa persamaan konstitutif kuningan dapat digambarkan dengan persamaan..."
Depok: Fakultas Teknik Universitas Indonesia, 1998
JUTE-XII-4-Des1998-342
Artikel Jurnal  Universitas Indonesia Library
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Aris Rosadi
"Aplikasi praktis dari solusi nanopartikel telah dibatasi karena memiliki dampak yang buruk pada degradasi mekanik. Tujuan penelitian ini adalah untuk menguji karakteristik aliran nanofluida. Hasil percobaan berupa kurva aliran dari nanofluida pada sebuah pipa kapiler yang mempunyai variabel tekanan. Yang diameter pipa tersebut adalah sebesar 3 mm. Tegangan geser dan regangan geser dihitung dengan mengukur pressure drop dan laju aliran volumetrik.
Pengukuran pressure drop dilakukan untuk Al2O3 dan TiO2 (konsentrasi 1%, 3% dan 5%) dengan menggunakan pressure tranducer. Power Law Index berada pada kisaran harga 0,95 - 1,0. Koefisien gesekan nanofluida yang telah didapat, dibandingkan dengan data dari air murni yang digambarkan dengan persamaan Blasius.

The practical application of the nanoparticle of solutions has been limited because it has an adverse effect on mechanical degradation. The aim of this study is to examine characteristics of flow properties of nanofluid. Experiments are carried out the measurement of the flow curve of the nanofluid by a capillary pipe applying variable pressure driven flow. It is 3 mm in the diameter of the capillary. The shear stress and the shear strain are calculated by measuring the pressure drop and the volumetric flow rate, respectively.
Measurements of pressure drop are carried out for Al2O3 and TiO2 at 1%, 3%, 5% particle volume with pure water by a pressure transducer. The power law exponent are about 0.95 - 1.0. The friction coefficient of nanofluid in a capillary pipe are fit with pure water data as Blasius's equation.
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Depok: Fakultas Teknik Universitas Indonesia, 2010
S52173
UI - Skripsi Open  Universitas Indonesia Library
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Chatarina Niken Dwi Wahyuni Setya Budi Utami
"[ABSTRAK
Penelitian susut dan rangkak di daerah tropis lembab ini dilakukan pada beton berkinerja tinggi fc’ 60 MPa dengan campuran tanpa abu terbang (TAT) dan dengan abu terbang (DAT). Spesimen susut berukuran 150х150х600 mm3 (3 buah) dan spesimen rangkak 200х600х2700 mm3 (1 buah). Pemberian beban dilakukan dengan cara pratekan sebesar 0.3 fc’ pada umur 15 hari, tulangan sebatas emberian beban tersebut. Ruang dikondisikan pada temperature 28±3OC dan kelembaban 72±5%.
Model dibuat berdasar pengamatan 800 hari dan 1000 hari. Data diolah dengan metode outlying ASTM E178-02 untuk nilai ekstrim dengan tingkat signifikansi 5%.
Tujuan penelitian ini adalah menghasilkan model rheologi susut dan rangkak beton berkinerja tinggi di daerah tropis lembab.
Model rheologi susut sampai jangka waktu 1000 hari adalah (H|N)-(H|N), sedangkan untuk rangkak (H|N)- (StV|N). Faktor koreksi susut untuk rasio air terhadap semen (w/cm) 0.26, 0.30, 0.34, dan 0.38 dalam jangka pendek (7-15 hari) berturut-turut adalah 1, 1.1, 2.1 dan 2.3, serta untuk jangka panjang 1, 1.13, 1.54 dan 1.65. Faktor koreksi jumlah semen sama dengan faktor koreksi ACI 209R Tropis lembab menyebabkan suhu maximum 24 jam pertama untuk skala penuh dapat
mencapai 2 kali suhu maximum di daerah non tropis lembab. Pencapaian suhu maximum tersebut setengah waktu pencapaian suhu maximum di daerah non tropis.
Laju regangan susut di daerah tropis lembab pada jangka pendek TAT adalah 1.1 dan jangka panjang 4.1 kali laju regangan ACI 209R dan bila dengan abu terbang 1.6 dan 2.4. Laju rangkak kedua campuran terhadap ACI adalah 0.8 untuk jangka pendek dan 1.8 untuk jangka panjang. Regangan susut jangka panjang terhadap ACI 209 untuk
TAT 1.7 dan DAT 1.4; sedang rangkak 1.3 dan 1.;

ABSTRACT
The research of shrinkage and creep in humid tropical weather area was done in highperformance concrete HPC fc of 6The research of shrinkage and creep in humid tropical weather area was done in high
performance concrete (HPC) fc’ of 60 MPa mixed with composition without fly ash called TAT and within fly ash called DAT. Three shrinkage specimens are 150х150х600 mm3 and one creep specimen is 200х600х2700 mm3. Loading was applied by prestressing of 0.3 fc’in 15th day, the reinforcement was limited by that prestressing. Room was set in 28 ± 3oC temperature and 72 ± 5% humidity. Rheological models were created based on 800 days and 1000 days
observation. Datas were processed by using ASTM E178-02 outlying methode for extreme value with 5% significant level.
The objective of this research is to create rheological models of shrinkage and creep of high performance concrete in humid tropical weather.
Shrinkage rheological model until the age of 1000 days is (H|N)-(H|N), while for creep is (H|N)- (StV|N). Shrinkage correction factors for water ratio to cement (w/cm) of 0.26, 0.30, 0.34, and 0.38 (7-15 days) are 1, 1.1, 2.1 and 2.3 respectively, and for long term are 1, 1.13, 1.54 dan 1.65. Correction factors of cement amount was similar with correction factor of ACI 209R.
Humid tropical area caused maximum temperature in first 24 hours could reach 2 times of maximum temperature in non humid tropical area (full scale). The maximum temperature achievement was much faster, that was a half of maximum temperature achievement in non humid tropical area. Reffered to ACI 209 R, the rate of shrinkage
in humid tropical area in short term is 1.1 and for long term is 4.1 times rate ACI 209R for TAT, 1.6 and 2.4 for DAT. Creep rate of the both mixture was compared with ACI 209R: 0.8 for short term and 1.8 for long term. Long term shrinkage strain of TAT and DAT was 1.7 and 1.4 times ACI 209R, while for creep was 1.3 and 1.0 MPa mixed with composition without fly ashcalled TAT and within fly ash called DAT Three shrinkage specimens are150 150 600 mm3 and one creep specimen is 200 600 2700 mm3 Loading wasapplied by prestressing of 0 3 fc in 15th day the reinforcement was limited by thatprestressing Room was set in 28 3oC temperature and 72 5 humidity Rheological models were created based on 800 days and 1000 daysobservation Datas were processed by using ASTM E178 02 outlying methode forextreme value with 5 significant level The objective of this research is to create rheological models of shrinkage and creepof high performance concrete in humid tropical weather Shrinkage rheological model until the age of 1000 days is H N H N while forcreep is H N StV N Shrinkage correction factors for water ratio to cement w cm of 0 26 0 30 0 34 and 0 38 7 15 days are 1 1 1 2 1 and 2 3 respectively and for long term are 1 1 13 1 54 dan 1 65 Correction factors of cement amount wassimilar with correction factor of ACI 209R Humid tropical area caused maximum temperature in first 24 hours could reach 2times of maximum temperature in non humid tropical area full scale The maximumtemperature achievement was much faster that was a half of maximum temperatureachievement in non humid tropical area Reffered to ACI 209 R the rate of shrinkagein humid tropical area in short term is 1 1 and for long term is 4 1 times rate ACI209R for TAT 1 6 and 2 4 for DAT Creep rate of the both mixture was comparedwith ACI 209R 0 8 for short term and 1 8 for long term Long term shrinkage strainof TAT and DAT was 1 7 and 1 4 times ACI 209R while for creep was 1 3 and 1 , The research of shrinkage and creep in humid tropical weather area was done in highperformance concrete HPC fc of 6The research of shrinkage and creep in humid tropical weather area was done in high
performance concrete (HPC) fc’ of 60 MPa mixed with composition without fly ash called TAT and within fly ash called DAT. Three shrinkage specimens are 150х150х600 mm3 and one creep specimen is 200х600х2700 mm3. Loading was applied by prestressing of 0.3 fc’in 15th day, the reinforcement was limited by that prestressing. Room was set in 28 ± 3oC temperature and 72 ± 5% humidity. Rheological models were created based on 800 days and 1000 days
observation. Datas were processed by using ASTM E178-02 outlying methode for extreme value with 5% significant level.
The objective of this research is to create rheological models of shrinkage and creep of high performance concrete in humid tropical weather.
Shrinkage rheological model until the age of 1000 days is (H|N)-(H|N), while for creep is (H|N)- (StV|N). Shrinkage correction factors for water ratio to cement (w/cm) of 0.26, 0.30, 0.34, and 0.38 (7-15 days) are 1, 1.1, 2.1 and 2.3 respectively, and for long term are 1, 1.13, 1.54 dan 1.65. Correction factors of cement amount was similar with correction factor of ACI 209R.
Humid tropical area caused maximum temperature in first 24 hours could reach 2 times of maximum temperature in non humid tropical area (full scale). The maximum temperature achievement was much faster, that was a half of maximum temperature achievement in non humid tropical area. Reffered to ACI 209 R, the rate of shrinkage
in humid tropical area in short term is 1.1 and for long term is 4.1 times rate ACI 209R for TAT, 1.6 and 2.4 for DAT. Creep rate of the both mixture was compared with ACI 209R: 0.8 for short term and 1.8 for long term. Long term shrinkage strain of TAT and DAT was 1.7 and 1.4 times ACI 209R, while for creep was 1.3 and 1.0 MPa mixed with composition without fly ashcalled TAT and within fly ash called DAT Three shrinkage specimens are150 150 600 mm3 and one creep specimen is 200 600 2700 mm3 Loading wasapplied by prestressing of 0 3 fc in 15th day the reinforcement was limited by thatprestressing Room was set in 28 3oC temperature and 72 5 humidity Rheological models were created based on 800 days and 1000 daysobservation Datas were processed by using ASTM E178 02 outlying methode forextreme value with 5 significant level The objective of this research is to create rheological models of shrinkage and creepof high performance concrete in humid tropical weather Shrinkage rheological model until the age of 1000 days is H N H N while forcreep is H N StV N Shrinkage correction factors for water ratio to cement w cm of 0 26 0 30 0 34 and 0 38 7 15 days are 1 1 1 2 1 and 2 3 respectively and for long term are 1 1 13 1 54 dan 1 65 Correction factors of cement amount wassimilar with correction factor of ACI 209R Humid tropical area caused maximum temperature in first 24 hours could reach 2times of maximum temperature in non humid tropical area full scale The maximumtemperature achievement was much faster that was a half of maximum temperatureachievement in non humid tropical area Reffered to ACI 209 R the rate of shrinkagein humid tropical area in short term is 1 1 and for long term is 4 1 times rate ACI209R for TAT 1 6 and 2 4 for DAT Creep rate of the both mixture was comparedwith ACI 209R 0 8 for short term and 1 8 for long term Long term shrinkage strainof TAT and DAT was 1 7 and 1 4 times ACI 209R while for creep was 1 3 and 1 ]"
2014
D2015
UI - Disertasi Membership  Universitas Indonesia Library
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Quadagno, Jill S.
New York: St. Martin's Press, 1980
612.6 QUA a
Buku Teks  Universitas Indonesia Library
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Asti Diar Safitri
"ABSTRAK
This project has an objective to reduce the use of cement for paste by replacing partial part of the concrete with limestone. This experiment focuses on the effect of the shear thickening behaviour to the behaviour of the paste and hence concrete. The idea of such a replacement is generated in order to reduce the effect of carbon footprint. In addition, the cost of cement paste production can be minimised as well since the percentage of cement in paste is reduced and replaced. Several pastes with various percentage of replacement were tested. Limestone as replacement has been proven to reduce the effect of shear thickening. The reduced effect of shear thickening is considered to be beneficial in construction industry.

ABSTRAK
Riset ini mempunyai tujuan untuk mengurangi penggunaan semen dalam pasta dengan mengganti beberapa bagian dari pasta dengan batu kapur. Eksperimen ini terfokus pada efek dari prilaku penebalan geser dengan prilaku pasta begitu juga beton. Ide pengganti tersebut dihasilkan dalam rangka mengurangu efek jejak karbon. Selain itu, biaya produksi pasta semen dapat diminimalkan karena persentase semen dalam pasta berkurang dan diganti. Beberapa pasta dengan persentase pengganti yang berbeda telah dites. Batu kapur sebagai material pengganti telah terbukti mengurangi efek dari penebalan geser. Berkurangnya penebalan gesel dinilai menguntungkan di dunia kontruksi."
[Depok, ]: Fakultas Teknik, Universitas Indonesia, 2017
S68044
UI - Skripsi Membership  Universitas Indonesia Library
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"Man above 50 years old as women who experience menopause, will show certain and specific problems . Middle age man often has a group of complaints, symptoms and syndromes that almost the same as women...."
Artikel Jurnal  Universitas Indonesia Library
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Armalia Nora Arlotas
"Proses penuaan menyebabkan terjadinya perubahan fungsi kognitif pada lansia. Penurunan kognitif dapat mempengaruhi kemampuan lansia dalam melakukan aktifitas sehari-hari. Sampel diambil dari populasi menggunakan tekhnik random sampling. Sampel yang diteliti sebanyak 51 responden. Analisa yang digunakan dalam penelitian ini adalah analisa bivariat dengan menggunakan uji Mann whitney. Instrumen yang digunakan berupa kuesioner dengan 37 pertanyaan dimana sebelumnya dilakukan uji validitas. Dari hasil analisis bivariat didapatkan hasil nilai p value 0,007 dimana dapat disimpulkan bahwa ada hubungan yang bermakna antara fungsi kognitif dengan kemampuan lansia melakukan aktifitas sehari-hari. Saran dari penelitian ini adalah perlunya dilakukan eksperimen tentang intervensi yang tepat untuk mencegah penurunan fungsi kognitif pada lansia.

Aging process causes some changes in the cognitive function of the elderly. The weakening cognitive ability may affect the capability of the elderly to perform activity daily living. Samples here are taken from the population by random sampling. The samples in this research consist of 51 respondents. The analysis used here is Bivariate analysis using Mann whitney test. Questionnaires are used as an instrument, consisting 37 questions where prior validity test is conducted. The bivariate analysis shows a result of p value 0.007, which concludes that there is a meaningful relationship between cognitive function and the activity daily living of elderly. This research further suggests the importance of conducting experiment on the right intervention to prevent the weakening of cognitive function of the elderly.
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Depok: Fakultas Ilmu Keperawatan Universitas Indonesia, [2014;2014, 2014]
S56268
UI - Skripsi Membership  Universitas Indonesia Library
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Matheus Nathanael
"Pendahuluan. Proses penuaan merupakan kondisi gangguan fungsi akibat penurunan integritas fisiologis yang dapat menjadi faktor risiko penyakit utama lain. Proses penuaan diakibatkan radikal bebas dan kondisi stres oksidatif sehingga dapat mempercepat proses penuaan. Kondisi ini menyebabkan peningkatan mediator proinflamasi, penurunan kognisi dan kekuatan otot. Berdasarkan studi, Acalypha indica Linn (AI) menunjukkan efek antioksidan dan antiinflamasi. Ekstrak tanaman herbal AI juga diketahui dapat menekan sitokin proinflamasi, meningkatkan kognisi dan kekuatan otot. Penelitian ini dilakukan untuk mengetahui pengaruh AI dalam proses penuaan melalui perlakuan terhadap tikus Sprague-Dawley (SD) tua.
Metode. Tikus SD terdiri dari Tikus SD tua (n=21) dan Tikus SD muda sebagai pembanding (n=6). Tikus SD tua dibagi menjadi tiga kelompok, yaitu kelompok perlakuan (ekstrak etanol AI 250 mg/kg berat badan), kontrol negatif, dan kontrol positif (vitamin E 6 IU). Kognisi tikus SD diuji menggunakan metode Y-maze sebelum dan selama perlakuan melalui uji setiap minggu. Perlakuan diberikan tikus selama 28 hari. Pada hari ke-29, kekuatan otot tikus dilakukan dengan metode grip test, setelah itu tikus diterminasi dan dilakukan pengukuran kadar interleukin-6 darah menggunakan enzyme-linked immunosorbent assay (ELISA).
Hasil. Ditemukan penurunan kadar IL-6 darah (p=0,02) dan peningkatan kekuatan otot (p=0,032) yang signifikan pada kelompok perlakuan (AI) dibandingkan dengan kontrol negatif. Namun, tidak memperlihatkan perbedaan yang signifikan pada kognisi tikus (p>0,05).
Kesimpulan. Ekstrak etanol AI dapat menurunkan kadar IL-6 darah dan meningkatkan kekuatan otot tikus SD tua, tetapi tidak memberikan efek yang signifikan terhadap kognisi tikus SD tua. Dibutuhkan penelitian lanjutan untuk melihat lebih jauh dan mendalam mengenai potensi AI sebagai agen antipenuaan.

Objectives. Aging is a condition of impaired function due to the decrease of physiological" "integrity that can be a risk factor for another disease. Aging process is caused by free radicals and oxidative stress that can increase proinflammatory mediators, such as interleukin-6. Acalypha indica Linn (AI), is widely used as a herbal medicine. Studies have shown that AI have antioxidant and antiinflammatory effects and known to suppress proinflammatory cytokines, improve cognition and muscle strength. We aimed to study the effects of AI in the aging process through treatment on aged Sprague-Dawley (SD) rats.
Methods. Old (n=21) and young SD rats as a comparison group (n=6). Aged rats were divided into treatment group (AI ethanolic extract 250mg/kg bodyweight), negative control, and positive control (6IU vitamin E). SD rats cognition was tested (Y-maze method) before and during treatment every week. Treatment was given for 28 days. On the 29th day, muscle strength was tested (grip test). SD rats were terminated and measured for its blood interleukin-6 levels using enzyme-linked immunosorbent assay (ELISA).
Results. Decrease in blood IL-6 levels (p=0.02) and an increase in muscle strength (p=0.032) significantly was found in the treatment group (AI) compared to negative control. Statistics did not show significant differences in rats cognition (p>0.05).
Conclusions. AI ethanolic extracts can reduce blood IL-6 levels and increase muscle strength on aged SD rats, but did not have a significant effect on its cognition. More research is needed to look further about the potential of AI as an antiaging agent.
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Jakarta: Fakultas Kedokteran Universitas Indonesia, 2018
S-Pdf
UI - Skripsi Membership  Universitas Indonesia Library
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