13 research outputs found
Deaktivasi Katalis Konverter-Hidrogen Di Pabrik Urea Kaltim-3
No full textDi pabrik urea, konverter-hidrogen adalah satu reaktor yang berfungsi untuk mengkonversi hidrogen yang terikut dalam karbondioksida dengan cara mengoksidasi dengan udara, sehingga karbondioksida umpan reaktor urea itu hanya mengandung tidak lebih dari 100 ppm hidrogen. Konversi dilangsungkan pada tekanan 145 kg/cm2 dan suhu umpan reaktor 130 C, menggunakan katalis platinum berpenyangga alumina (0,3%Pt/Al2O3). Dalam dua tahun terakhir, terjadi kenaikan kandungan hidrogen dalam karbondioksida umpan konverter-hidrogen Kaltim-3 yang menyebabkan peningkatan temperatur keluaran konverter dari biasanya sekitar 152oC menjadi sekitar 190 C. Hasil analisis kadar Pt, luas permukaan katalis dan dispersi Pt terhadap katalis-baru dan katalis-terpakai menunjukkan bahwa katalis konverter-hidrogen Kaltim-3 telah terdeaktivasi. Oleh karena itu, pada kesempatan perbaikan-tahunan Juli 2006 yang lalu, katalis tersebut telah diganti dengan yang baru. Selain itu telah dilakukan pula perbaikan kondisi operasi di pabrik amoniak Kaltim-3, sehingga kadar H2 dalam aliran CO2 umpan pabrik urea Kaltim-3 menjadi normal kembali (0,4%). Dengan tindakan-tindakan tersebut, sejak Agustus 2006 yang lalu konverter hidrogen Kaltim-3 dapat beroperasi secara normal kembali. © 2007 BCREC UNDIP. All rights reserved.[Presented at Symposium and Congress of MKICS 2007, 18-19 April 2007, Semarang, Indonesia][How to Cite: A. Subekti, A.S. Arief, P. Praharso, S. Subagjo. (2007). Deaktivasi Katalis Konverter-Hidrogen Di Pabrik Urea Kaltim-3. Bulletin of Chemical Reaction Engineering and Catalysis, 2 (2-3): 52-55. doi:10.9767/bcrec.2.2-3.10.52-55][How to Link/DOI: http://dx.doi.org/10.9767/bcrec.2.2-3.10.52-55 ] </p
The autothermal reforming of artificial gasoline
No full textStringent legislation on control of vehicle exhaust emissions has led to consideration of alternative means of reducing emissions, with hydrogen fuel cell powered vehicles being accepted as one favoured possibility. However, the difficulties of storing and distributing hydrogen as a fuel are such that the conversion of more readily available fuels to hydrogen on board the vehicle may be required. The production of hydrogen by the partial oxidation of isooctane over Rh/Al2O3, Rh/CeO2-?l2O3 and Rh/CeO2-ZrO2 catalysts has been investigated. Oxidation was initiated at temperatures between 200 ?220 oC. The yield of hydrogen was 100%. CeO2-ZrO2 was found to be the best support. The production of hydrogen by the autothermal reforming of artificial gasoline has been studied. Part of gasoline is oxidised to produce heat and steam to promote the steam reforming of unburnt gasoline to produce hydrogen. The use of platinum impregnated on ceria supports (active for oxidation) and a commercial nickel based catalyst (Ni-com), for steam reforming of gasoline have been explored. Initiation of oxidation of artificial gasoline over unreduced platinum based catalysts occurred at temperature as low as 150 oC, depending on the oxygen:carbon ratio and the liquid hydrocarbon used. Detailed kinetic studies of the steam reforming of isooctane and artificial gasoline (a mix of cyclohexane, isooctane and octane) over pre-reduced Ni-com catalysts showed that the reaction was 0.17 order in isooctane and 0.54 order in steam, whilst the reaction was 0.08 order in artificial gasoline and 0.23 order in steam. Mechanisms have been proposed to account for the dual site surface reaction with dissociative adsorption of isooctane or artificial gasoline and steam. Combined oxidation and steam reforming systems (autothermal reforming) using Pt/CeO2 as a front catalyst bed and Ni-com as the rear bed at the feed conditions of oxygen:carbon (O:C) ratio of ca.1.2 and steam:carbon (S:C) ratio of ca.2, produces ca. 3.5 moles of hydrogen per mole of gasoline fed. The system reaction temperature could be controlled by adjusting the O:C and S:C ratios in feed
Losing ground: Social identity loss predicts depression following a life transition
No full textLife transitions can be a positive life experience and provide opportunities for personal growth. However, undergoing a life transition can also be stressful and overwhelming and precipitate depression. The stress-buffering hypothesis (Cohen & Wills, 1985) postulates that social support buffers against the negative effects of stressful life events and can attenuate the development of depressive symptoms, but unfortunately has not been well-supported by longitudinal studies. In contrast, the social identity approach to wellbeing (Jetten, Haslam, & Haslam, 2012) suggests that group memberships lead to substantial health benefits, with an emerging number of studies showing promising results. Based on this approach, the present study assesses how changes in social identification during a life transition affect mental wellbeing and depression throughout the life transition. First-year International students (N = 52) reported their group memberships and wellbeing at the beginning and end of their first semester of studies, approximately four months later. Results show that lack of important group memberships at the end of the transition contributes to increased levels of depressive symptoms, even when controlling for initial levels of depression and important group memberships at the beginning of the transition. Theoretical and practical implications are discussed in relation to these results
Penerapan Peraturan Daerah Kota Tangerang Nomor 7 Tahun 2004 Tentang Larangan Kegiatan Permainan Layang-layang Bagi Keselamatan Penerbangan
No full textPermainan layang-layang merupakan permainan yang dilarang di sekitar wilayah Bandara Soekarno-Hatta sebagaimana yang diatur dalam Peraturan Daerah Kota Tangerang Nomor 7 Tahun 2004 karena dapat mengancam keselamatan penerbangan. Namun demikian, sosialisasi serta sanksi yang diberikan oleh pihak berwajib setempat terhadap masyarakat saat ini dirasakan masih jauh dari harapan dan belum mampu secara maksimal memberikan dampak positif bagi masyarakat. Penulis mengangkat skripsi ini, dengan tujuan untuk mengetahui sejauh mana efektivitas penegakkan hukum Peraturan Daerah Kota Tangerang Nomor 7 Tahun 2004 tentang Larangan Menerbangkan atau Menaikkan Layang-layang dan/atau Permainan Sejenisnya Serta Kegiatan Lain yang Mengganggu Keselamatan Penerbangan di Bandar Udara Soekarno-Hatta dan sekitarnya juga mengetahui hambatan serta upaya Pemerintah Kota Tangerang dan para stakeholder terkait dalam menegakkan Peraturan Daerah ini. Untuk membahas persoalan diatas, dalam penelitian ini penulis menggunakan metode penelitian Normatif. Berdasarkan data yang diperoleh melalui wawancara, diketahui bahwa masih terdapat masyarakat yang melakukan pelanggaran. Faktor yang menjadi hambatan para stakeholder terkait dalam penegakan Perda yakni, faktor hukum, faktor penegak hukum, faktor sarana atau fasilitas dan faktor masyarakat yang menjadi hambatan dalam mengatasi permainan layang-layang di Kecamatan Neglasari, Benda, Batuceper, dan Sepatan. Faktor-faktor tersebut mempengaruhi penerapan Peraturan Daerah Kota Tangerang Nomor 7 Tahun 2004 Tentang Larangan Menerbangkan atau Menaikkan Layang-layang dan/atau Permainan Sejenisnya Serta Kegiatan Lain yang Mengganggu Keselamatan Penerbangan
PENGARUH RASIO EFEKTIVITAS PENDAPATAN ASLI DAERAH (PAD), DANA ALOKASI UMUM (DAU), DAN DANA BAGI HASIL PAJAK (DBHP) TERHADAP TINGKAT OTONOMI FISKAL (Studi Pada Kabupaten/ Kota di Provinsi Jawa Tengah)
No full textPenelitian ini bertujuan untuk menguji pengaruh Rasio Efektivitas
Pendapatan Asli Daerah (PAD), Dana Alokasi Umum (DAU), dan Dana Bagi
Hasil Pajak (DBHP) terhadap Tingkat Otonomi Fiskal (Kemandirian Keuangan).
Data yang digunakan dalam penelitian ini adalah data sekunder dari laporan
Realisasi Pendapatan dan Belanja Pemerintah Kabupaten/ Kota di Provinsi Jawa
Tengah tahun 2007 sampai dengan tahun 2009. Model analisis yang digunakan
adalah multiple regression.
Hasil Penelitian menunjukkan bahwa secara simultan variabel Rasio
Efektivitas Pendapatan Asli Daerah (PAD), Dana Alokasi Umum (DAU) dan
Dana Bagi Hasil Pajak (DBHP) berpengaruh secara signifikan positif terhadap
Tingkat Otonomi Fiskal (Kemandirian Keuangan). Secara parsial variabel Dana
Alokasi Umum berpengaruh secara signifikan negatif terhadap Tingkat Otonomi
Fiskal (Kemandirian Keuangan). Sedangkan variabel Rasio Efektivitas
Pendapatan Asli Daerah (PAD) dan Dana Bagi Hasil Pajak (DBHP) tidak
berpengaruh secara signifikan terhadap Tingkat Otonomi Fiskal (Kemandirian
Keuangan).
Kata kunci: Tingkat Otonomi Fiskal, Rasio Efektivitas Pendapatan Asli Daerah
(PAD), Dana Alokasi Umum (DAU), Dana Bagi Hasil Pajak (DBHP
Modeling Waste Heat Recovery System of Industrial Ammonia Process Plant Using LPV Identification
No full textStressful life transitions and wellbeing: a comparison of the stress buffering hypothesis and the social identity model of identity change
No full textThe relationship between stressful life transitions and wellbeing is well established, however, the protective role of social connectedness has received mixed support. We test two theoretical models, the Stress Buffering Hypothesis and the Social Identity Model of Identity Change, to determine which best explains the relationship between social connectedness, stress, and wellbeing. Study 1 (N=165) was an experiment in which participants considered the impact of moving cities versus receiving a serious health diagnosis. Study 2 (N=79) was a longitudinal study that examined the adjustment of international students to university over the course of their first semester. Both studies found limited evidence for the buffering role of social support as predicted by the Stress Buffering Hypothesis; instead people who experienced a loss of social identities as a result of a stressor had a subsequent decline in wellbeing, consistent with the Social Identity Model of Identity Change. We conclude that stressful life events are best conceptualised as identity transitions. Such events are more likely to be perceived as stressful and compromise wellbeing when they entail identity loss
Silent stories and puzzled paradigms: A reflexive autoethnography of identity, motherhood, and dominant discourse
No full textIdentity development continues across the lifespan, revisited as transitions spark new beliefs and life experiences demand new ways of being; a re-examination of old patterns, beliefs, relationships, and visions of what one might become (Bogaerts et al., 2019; Meca et al., 2020; Piotrowski, 2020). The purpose of this research is to explore the concept of self and identity for a mother when the maternal role includes the discrepant identity exploration of adolescent offspring.
Maternal identity is an amalgamation of roles, responsibilities, and attitudes that can be disrupted when sudden changes or challenges exceed an individual’s perceived coping and reasoning skills (Piotrowski, 2020; Praharso et al., 2017; Stanley & Stanley, 2017). These disruptions often become moments of crisis; turning points where group membership is questioned and previously held beliefs and patterns of behavior are re-considered in exchange for new ways of thinking, being, believing, and becoming (Bogaerts et al., 2019; Fossas, 2019; Praharso et al., 2017).
Data for this autoethnographic research are gathered from artifacts dated between 2015-2021; drawn from personal journal entries, yoga class notes, voice recorded notes, and hand drawn doodles. Revisiting one’s identity, middle stage mothers are at increased risk of internalizing responsibility, resulting in a cycle of shame and self-blame that Through reflection or rumination, an individual will craft a storied narrative of self and other that provides the backdrop for the event related outcomes that pave the path to stagnation or transformative meaning making that impacts mental health, relational satisfaction, well-being, and one’s sense of self (Bogaerts et al., 2019; Hardy et al., 2017; Meca et al., 2020; van Halen et al, 2020).
Results from this study illustrate that, both, the significant and mundane moments may result in seismic and subtle paradigm shifts that can wreak havoc on middle-stage maternal identity and domain specific distress (Li et al., 2019; Luthar & Ciciolla, 2015; Luthar, 2016; Meca et al., 2020). Offering an analysis of the lived experience of self and identity, this research concludes with implications for help professionals and future research
