Claim Missing Document
Check
Articles

Pengaruh Penambahan Bubuk Aerosil Pada Uji Drop Test Material Komposit Serat Daun Nanas Dan Serbuk Arang Harijono, Harijono; Fanani, Ahmad; Hartono, Hartono
Jurnal Pengelolaan Laboratorium Vol 3 No 1 (2024): Februari
Publisher : Politeknik Negeri Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25047/plp.v3i1.4635

Abstract

Komposit adalah campuran dua bahan atau juga lebih yang terdiri dari matriks dan penguat/ serat. Pada umumnya penelitian di lakukan memakai satu jenis serat. Oleh karena itu, penulis menggunakan kombinasi serat daun nanas dan serbuk arang sebagai bahan penguat polymer hybrid composite untuk menghasilkan sifat gabungan antara kedua penguat tersebut.Penelitian ini dapat memberikan informasi kepada pembaca terkait kekuatan dan ketangguhan polymer hybrid composite dengan penguat serat daun nanas dan serbuk arang. Seperti yang sudah pada penelitian sebelumnya yaitu “Rekayasa KekuatanImpak Terhadap Polymer Hybrid Composite Fariasi Penambahan Serat Daun Nanas Dan Serbuk Arang”. Dari Hasil penelitian tersebut menunjukkan bahwa kekuatan Impak meningkat seiring dengan bertambahnya fraksi volume serat daun nanas yang diakibatkan oleh pendistribusian beban yang baik. Berbagai latar belakang di atas memunculkan gagasan untuk melakukan penelitian tentang variasi penambahan serat daun nanas dan serbuk arang dalam pembuatan polymer hybrid composite terhadap kekuatan Uji Tumbuk/ Drop. Pengujian Uji Tumbuk/Drop ini menggunakan pendulum yang beratnya adalah 0,5 kg, dengan ketinggian 3 meter dari jarak pendulum ke speciment. Dengan ketebalan speciment rata rata adalah 1,5 mm. Material atau speciment dengan perbandingan volume filler antara serat daun nanas dan serbuk arang antara 10% : 30% mendapatkan kondisi yang getas atau kurangnya serat, sehingga apabila terkena hantaman pendulum dengan berat 0,5 kg dengan ketinggian 3 meter maka akan menimbulkan luka berat atau berlubang di permukaan speciment. Speciment dengan perbandingan volume filler antara serat daun nanas dan serbuk arang antara 30% : 10% mendapatkan kondisi yang baik, yaitu tidak adanya lubang atau kawah yang terlalu besar, hanya saja menimbulkan kawah yang kecil di permukaan speciment.
PERUBAHAN MORFOLOGI DAN FISIKOKIMIA TEPUNG UWI (Dioscorea alata) AKIBAT FERMENTASI ALAMI DAN PENGERINGAN Indrastuti, Erning; Harijono, Harijono; Susilo, Bambang
Jurnal Agroindustri Vol. 14 No. 2 (2024): November 2024
Publisher : BPFP Faperta UNIB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31186/jagroindustri.14.2.155-166

Abstract

Penelitian ini mempunyai tujuan untuk mengevaluasi perubahan morfologi dan fisikokimia tepung uwi selama perendaman dan pengeringan secara simultan. Irisan umbi uwi direndam selama 0, 24, dan 48 jam yang menyebabkan fermentasi alami, irisan umbi basah dikeringkan pada pengering kabinet selama 18 jam pada suhu pengeringan 40, 50, dan 60 °C.  Irisan umbi uwi kering dihaluskan sampai 100 mesh dan dilanjutkan dengan analisis morfologi granula, kadar pati, kadar amilosa, kadar protein, kadar serat kasar, pH, titratable acidity, warna tepung uwi dan analisis gugus fungsi menggunakan ATR-FTIR.  Hasil penelitian menunjukkan terdapat lubang pada permukaan granula pati hasil fermentasi 48 jam. Keberadaan lubang pada permukaan granula menyebabkan leaching amilosa yang menyebabkan perubahan pada karakteristik fisikokimia pati. Interaksi lama perendaman dan suhu pengeringan berpengaruh sangat nyata terhadap kadar pati dan warna. Semakin lama fermentasi alami dan semakin tinggi suhu pengeringan akan menurunkan kadar pati, nilai kecerahan L*, kemerahan a* dan kebiruan b*.  Lama fermentasi alami menurunkan amilosa, protein larut air, serat kasar, dan pH, meningkatkan titratable acidity, namun tidak dipengaruhi oleh suhu pengeringan. Struktur molekul pati uwi hampir tidak berubah setelah fermentasi alami dan pengeringan, ditunjukkan tidak adanya gugus fungsi baru pada spektra FTIR. Karakteristik tepung uwi yang terbaik dari perlakuan fermentasi alami selama 24 jam dan pengeringan 60 °C dengan kadar pati 72,02%, rendemen, 24,595, kadar amilosa 31,07%, kadar protein larut 2,74%, kadar serat kasar 1,56%, pH 5,88, titratable acidity 0,68, kelarutan 13,28%, L* 67,9, a* 3,6, b* -2.
Carbon Productivity’s Impact on Company's Financial Performance (Case Study of Companies Listed on IDX80 Stock Index) Tehananda, Djie Liveren Adjie; Robiyanto; Harijono, Harijono
Journal of Management and Entrepreneurship Research Vol. 5 No. 2 (2024)
Publisher : Universitas Islam Nahdlatul Ulama Jepara

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.34001/jmer.2024.12.05.2-53

Abstract

Objective: Environmental issues are a concern, especially global warming. One of the consequences of global warming is a significant increase in carbon emissions each year. However, investors are trying to understand whether increased carbon also improves companies' financial performance. This study seeks to investigate the influence of carbon productivity on the company’s financial performance (case study of companies listed on the IDX80 index). Research Design & Methods: This research uses a quantitative method with secondary data taken from the company's annual and sustainability reports from 2020 to 2023. The sampling method used is the purposive sampling method. The sample used in this research was 80 companies listed on the IDX80 Index. Panel Data Regression Analysis is used to analyze the data. Findings: The findings of the study indicated carbon productivity has no significant effect on company financial performance, whether measured through ROA or MBR On the other hand, when control variables are added, they have a significant effect on the company's financial performance as measured through ROA. Implications and Recommendations: From these findings, stakeholders, investors and financial managers in the Indonesian capital market can help in making investment decisions, especially regarding the influence of carbon productivity on financial performance and for stakeholders. Contribution & Value Added: This study adds value to the practice of finance that seeks to see that companies that disclose higher carbon emissions will affect the company's financial performance in the context of developing countries, especially Indonesia.
Ultrasonic assisted extraction modelling and phytochemicals profiling of bangle rhizome (Zingiber cassumunar Roxb.) Utama, Niko; Martati, Erryana; Harijono, Harijono
Advances in Food Science, Sustainable Agriculture and Agroindustrial Engineering (AFSSAAE) Vol 8, No 1 (2025)
Publisher : Advances in Food Science, Sustainable Agriculture and Agroindustrial Engineering (AFSSAAE)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.afssaae.2025.008.01.9

Abstract

Zingiber Cassumunar Roxb., locally known as bangle, has pharmacological activities as an antioxidant, anti-inflammatory, anticancer, neuroprotective, and antibacterial. Green technology extractions have more advantages than conventional extraction. Therefore, this study aims to model the extraction conditions of ultrasound-assisted extraction (UAE) using the Box-Behnken design (BBD) response surface method. Extraction of the bangle was performed using an ultrasonic bath with various bangle-to-ethanol ratios (1:15, 1:30, and 1:45 w/v), ethanol concentrations (60, 70, and 80%), and extraction times (5, 15, and 25 min). The program selected the quadratic model prediction to determine the relationship between bangle-to-ethanol ratio, ethanol concentration, and extraction time on the total phenolics and antioxidant activity. The optimization results showed that the optimum conditions for bangle rhizome extraction were a bangle-to-ethanol ratio of 1:45 w/v, an ethanol concentration of 70%, and an extraction time of 25 min. Under these conditions, total phenolic compounds of 5.48 mg GAE/g and antioxidant activity of 69.18% were obtained. The model had a desirability value of 0.938. The model agreed with the predicted antioxidant activity values (p >0.05). Furthermore, five phenolic group compounds, 11 coumarin group compounds, and 10 alkaloid group compounds were identified using LC-MS/MS QTOF.
Analisis Herding Behavior Sebelum Dan Sesudah Penghapusan Kode Broker Di Bursa Efek Indonesia Cahyono, Aji Wikan; Robiyanto, Robiyanto; Harijono, Harijono
Magisma: Jurnal Ilmiah Ekonomi dan Bisnis Vol 12 No 1 (2024): MAGISMA:Jurnal Ilmiah Ekonomi dan Bisnis
Publisher : Magister Manajemen STIE Bank BPD Jateng

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35829/magisma.v12i1.377

Abstract

This research was conducted to see if there was any herding behavior in stock trading in Indonesia, especially the LQ45 index constituents, which were affected by the effect of the removal of the broker code by the Indonesian Stock Exchange which began on December 6, 2021. The period used in this study was the period before the removal of the broker code, namely June 15, 2020 to December 5, 2021 and the period after the removal of the broker code, namely December 6, 2021 to June 30, 2023. The method used in this study is the approach method by Chang et al. (2000) namely CSAD (Cross Sectional Absolute Standard Deviation) to detect indications of herding behavior. The results of this study indicate that there was no herding behavior on the LQ45 trading stock index either before or after the removal of the broker code. This means that investors act rationally whether the broker code exists or not
IMPLEMENTASI PENJAMINAN MUTU PADA PROSES PRODUKSI MINUMAN JAHE INSTAN SKALA INDUSTRI KECIL MENENGAH Estiasih, Teti; Ahmadi, Kgs; Harijono, Harijono
TEKNOLOGI PANGAN : Media Informasi dan Komunikasi Ilmiah Teknologi Pertanian Vol 9 No 2 (2018)
Publisher : Program Studi Ilmu dan Teknologi Pangan, Universitas Yudharta, Pasuruan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35891/tp.v9i2.1193

Abstract

Penjaminan mutu pada proses produksi pangan merupakan suatu tuntutan yang harus dipenuhi oleh semua produsen. Banyak kendala yang dihadapi bagi industry kecil menengah (IKM) dalam penerapan penjaminan mutu. Salah satu IKM yang mengimplementasikan penjaminan mutu berbasis Hazard Analyziz and Critical Control Point adalah IKM DIA yang memproduksi minuman jahe instan. Jahe instan merupakan produk yang berisiko rendah ( low risk ) dari segi keamanan pangan, tetapi penjaminan mutu harus diterapakn untuk menghasilan produk yang aman dan layak dikonsumsi. Upaya untuk implementasi tersebut adalah melalui penerapan cara-cara pengolahan pangan yang baik (GMP, Good Manufacturing Practices ), dan penerapan HACCP. Implementasi dilakukan secara bertahap melalui pemenuhan 18 runga lingkup GMP. Hasil penilaian GMP menunjukkan bahwa IKM ini terkategori baik dengan beebrapa perbaikan harus dilakukan. Penerapan rencana HACCP sesuai 7 prinsip HACCP telah dilakukan. Hasil audit HACCP menunjukkan perlu adanya perbaikan minor meliputi perbaikan ruang produksi, peningkatan kelengkapan sanitasi pekerja, perbaikan sanitasi ruang produksi, dan perbaikan pelabelan.
Rekayasa Kekuatan Tarik terhadap Polymer Hybrid Composite Fariasi Penambahan Serat Daun Nanas dan Serbuk Arang Harijono, Harijono; Juhan Syah, Fahmi; Hartono
Jurnal Pengelolaan Laboratorium Vol 1 No 2 (2022): Agustus
Publisher : Politeknik Negeri Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25047/plp.v1i2.3016

Abstract

Pada saat ini permintaan bahan semakin meningkat dengan sifat mekanis yang baik serta ekonomis. Sebagai upaya untuk memenuhi kebutuhan tersebut maka digunakanlah bahan komposit. Komposit adalah gabungan dua atau lebih material yang tercampur secara tidak homogen terdiri dari matriks dan penguat. Berbagai penelitian yang dilakukan umumnya menggunakan satu macam jenis serat sehingga sifat komposit bergantung pada satu serat yang digunakan. Oleh karena itu, penulis menggunakan kombinasi serat daun nanas dan serbuk arang sebagai bahan penguat polymer hybrid composite untuk menghasilkan sifat gabungan antara kedua penguat tersebut. Penelitian yang telah dilakukan memiliki tujuan mengetahui pengaruh variasi penambahan serat daun nanas dan serbuk arang terhadap kekuatan tarik dan ketangguhan impak polymer hybrid composite. Selain itu penelitian bermanfaat memberikan informasi kepada pembaca terkait kekuatan dan ketangguhan polymer hybrid composite dengan penguat serat daun nanas dan serbuk arang. Terdapat tiga variasi perbandingan serat daun nanas dan serbuk arang yaitu 10%:30%, 20%:20%, dan 30%:10% yang digunakan pada uji tarik. Hasil penelitian menunjukkan bahwa kekuatan tarik meningkat seiring dengan bertambahnya fraksi volume serat daun nanas yang diakibatkan oleh pendistribusian beban yang baik serta kemampuan menahan beban tarik yang meningkat. Adapun hasil rata-rata ultimate tensile strength masing-masing 30,15 N/mm2, 41,56 N/mm2, dan 63,59 N/mm2. Sedangkan nilai ketangguhan yang semakin menurun seiring dengan pertambahan serat daun nanas karena ikatan antara serat dengan matriks yang semakin melemah Adapun hasil rata-rata harga impak masing-masing 0,50 J/mm2, 0,44 J/mm2, dan 0,38 J/mm2
Rekayasa Ketangguhan Impak Terhadap Polymer Hybrid Composite Fariasi Penambahan Serat Daun Nanas Dan Serbuk Arang Harijono, Harijono; Akhmad, Akhmad; Hartono, Hartono
Jurnal Pengelolaan Laboratorium Vol 2 No 2 (2023): Agustus
Publisher : Politeknik Negeri Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25047/plp.v2i2.3686

Abstract

At the moment the demand for materials is increasing with good mechanical properties as well as economical. As an effort to meet these needs, composite materials are used. A composite is a combination of two or more inhomogeneously mixed materials consisting of a matrix and a reinforcement. Various studies conducted generally use one type of fiber so that the composite properties depend on one fiber used. The research that has been carried out has the aim of determining the effect of variations in the addition of pineapple leaf fiber and charcoal powder on the tensile strength and toughness of the impact of polymer hybrid composites. In addition, useful research provides information to readers regarding the strength and toughness of polymer hybrid composite with pineapple leaf fiber reinforcement and charcoal powder.There were three variations in the ratio of pineapple leaf fiber and charcoal powder, namely 10%:30%, 20%:20%, and 30%:10% used in the tensile test. The results showed that the tensile strength increased along with the increase in the volume fraction of pineapple leaf fiber due to good load distribution and the ability to withstand increased tensile load.The average yield of absorbent energy of polymer hybrid composites is 35.81 J, 35.526 J, and 30.93 J, respectively, while the toughness value decreases along with the increase in pineapple leaf fiber due to the bond between the fibers and the matrix that is getting weaker As for the average yield of impact prices of 0.506 J/mm2, 0.466 J/mm2, and 0.39 J/mm2, respectively Keywords: Composite, Polymer Hybrid Fiber Composite, impact, Matrix.
An Empirical Study of Bonds as a Safe Haven in Indonesia During COVID-19 and Russia-Ukraine War Arifin, Fahmi Ihwanul; Robiyanto, Robiyanto; Noegroho, Yefta Andi Kus; Harijono, Harijono
Media Ekonomi dan Manajemen Vol 41, No 1 (2026): January 2026
Publisher : Fakultas Ekonomika dan Bisnis UNTAG Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.56444/mem.v41i1.6311

Abstract

This study examines whether government and corporate bonds in Indonesia act as hedging or safe haven assets during the COVID-19 pandemic and the Russia–Ukraine war. This study using data started from March 3, 2020 which is the date of the first Covid-19 case emerged in Indonesia to March 29, 2024 even though the war is not over yet on the time this study being conducted. The cut-off date for the Russia-Ukraine war is February 24, 2022. Generalized Autoregressive Conditional Heteroskedasticity (GARCH) is used in order to test the potential of bonds as hedges, while QREG used in order to test the potential of bond as safe haven. The findings show that during the period of financial and geopolitical crisis, Indonesian government and corporate bonds cannot be an effective safe haven or hedge against the stock market. While they can serve as diversification assets due to their stable volatility, these bonds lack the consistent negative correlation with the Composite Stock Price Index (CSPI) required for safe haven assets. Investors and portfolio managers should be cautious in relying on government bonds and corporate bonds as hedge against stock market declines. The results suggest that bonds may not provide the expected protection against stock market declines, so investors need to consider alternative diversification strategies or other hedging instruments when making investment decisions.
Determinants of United States - Indonesia Equity Market’s Dynamic Correlation: The Role of Commodities and Exchange Rate’s Volatilities Robiyanto, Robiyanto; Pangesti, Essy Indah; Harijono, Harijono; Frensidy, Budi
Media Ekonomi dan Manajemen Vol 38, No 2 (2023): July 2023
Publisher : Fakultas Ekonomika dan Bisnis UNTAG Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.56444/mem.v38i2.3595

Abstract

This study aims to analyze the effect of oil price volatility, gold price volatility and exchange rate volatility on the dynamic relationship between Indonesian and United States capital market. The data used in this study are daily closing prices of oil, gold and exchange rates (USD/IDR) as well as Indonesian capital market (JKSE) and United States capital market (DJIA) composite indices during period of January 2005 to October 2020. This study uses DCC-GARCH method to calculate the dynamic correlation between two capital markets and GARCH with the GED parameter to analyze oil volatility, gold volatility and exchange rate volatility on the integration of Indonesian capital market and United States capital market. The results of this study show positive and strong results on the integration of Indonesian and United States capital markets, thus proving that the movements of Indonesian market and American market tend to be strong and mutually influence the two capital markets. Moreover, the oil, gold and exchange rates volatilities have a negative effect on the integration of the Indonesia capital market and the US capital market. This finding implies investors should take oil, gold and exchange rates volatilities in their investment consideration.