Articles

Found 34 Documents
Search

RESIDU PESTISIDA PIRETROID PADA BAWANG MERAH DI DESA SRIGADING KECAMATAN SANDEN KABUPATEN BANTUL

PHARMACIANA Vol 2, No 2: November 2012
Publisher : PHARMACIANA

Show Abstract | Original Source | Check in Google Scholar | Full PDF (81.237 KB)

Abstract

Telah dilakukan penelitian terhadap residu pestisida piretroid pada sampel bawang merah di Desa Srigading, Kecamatan Sanden, Kabupaten Bantul. Penelitian ini bertujuan untuk menganalisis, mengidentifikasi dan mengevaluasi residu pestisida piretroid pada bawang merah. Sampel bawang merah diekstraksi menggunakan alat homogenizer dengan pelarut aseton. Clean-up dilakukan dengan kolom kromatografi menggunakan florisil dan selanjutnya kadar residu pestisida ditentukan dengan kromatografi gas yang dilengkapi dengan detektor tangkapan elektron (Electron Capture Detector/ECD). Hasil penelitian menunjukkan bahwa sampel bawang merah terdeteksi adanya residu pestisida piretroid (_-sipermetrin dan _-sihalotrin). Kisaran residu pestisida pada sampel bawang merah untuk _-sipermetrin (98,8-245,6 ppb) dan _-sihalotrin (14,4-120,0 ppb). Terdapat sampel bawang merah yang melebihi Batas Maksimum Residu (BMR).

PREPARASI DAN KARAKTERISASI KOMPOSIT KROMIUM OKSIDA-MONTMORILLONIT

Journal of Chemistry Vol. 2, No. 2 Juli 2008
Publisher : Journal of Chemistry

Show Abstract | Original Source | Check in Google Scholar

Abstract

The objectives of this research were to prepare montmorillonite and of chromium oxide-montmorillonitecomposite by intercalation of oxide of chrom into the silicates interlayer of montmorillonite, and to characterizesome of their physical and chemical properties. The characterization indicated that the basal spacing d001 wasincreased from 14,11 in montmorillonit to 15,55 in chromium oxide-montmorillonite; specific surface area wasincreased from 69,71 m2/g to 240,40 m2/g; total pore volume was also increased from 0,05 mL/g to 0,128 mL/g; andchrom content also increased from 0,007% (w/w) to 17,16 % (w/w).

Pengambilan Ion Logam Mn2+ dan Ni2+ Menggunakan Na-Zeolit: Suatu Usaha Pengkajian Pemanfaatan Sumber Daya Alam Indonesia

Jurnal Kimia Sains dan Aplikasi Vol 7, No 2 (2004): Volume 7 Issue 2 Year 2004
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Original Source | Check in Google Scholar | Full PDF (168.489 KB)

Abstract

Zeolit alam asal Cikalong Jawa Barat telah digunakan untuk pengambilan ion Mn2+ dan Ni2+ dari larutannya, dengan cara mempertukarkan ion-ion tersebut dengan ion Na+ dalam zeolit alam termodifikasi berdasarkan sistem batch. Penelitian ini juga mengkaji pengaruh keberadaan ion Cu2+ di dalam sistem pertukaran kation. Konsentrasi ion-ion dianalisis dengan metode spektrofotometri serapan atom. Data eksperimen menunjukkan bahwa zeolit alam yang telah dimodifikasi dengan Na+ dapat digunakan untuk mengambil ion Mn2+ dan Ni2+ melalui mekanisme pertukaran kation. Uji selektivitas memperlihatkan bahwa Na-Zeolit lebih selektif terhadap Mn2+ dibandingkan terhadap Ni2+. Urutan selektivitas ini tidak dipengaruhi oleh keberadaan Cu2+. Na-Zeolit mampu mempertukarkan kation Mn2+ sampai 57,73 % dalam keadaan sendiri dan 19,72 % dalam keadaan bersama; Ni2+ sampai 37,71 % dalam keadaan sendiri dan hanya 5,81 % dalam keadaan bersama kation logam lain di dalam larutannya.

Optimum Concentration of Glucose and Orange II for Growth and Decolorization of Orange II by Enterococcus faecalis ID6017 under Static Culture

Microbiology Indonesia Vol 2, No 2 (2008): August 2008
Publisher : Indonesian Society for microbiology

Show Abstract | Original Source | Check in Google Scholar

Abstract

Growth and decolorization performance of bacterial grown on azodyes-containing-medium is influenced by various concentrations of carbon sources and azodyes. The optimum level of glucose and Orange II concentration for growth and Orange II decolorization by Enterococcus faecalis ID6017 are reported in this paper. The experiments were carried out in liquid static culture as batch experiments. Glucose and Orange II concentrations used in these experiments were 0.45, 0.90, 1.80 g l-1, and 40, 80, 120 mg l-1, respectively. The specific growth rate and decolorization rate of Orange II by E. faecalis were highest on the medium which contained at least 0.90 g l-1 glucose. It is necessary to note that glucose above 0.90 g l-1 gave no significant difference. On the medium containing 0.90 g l-1 glucose and 80 mg l-1 Orange II, E. faecalis grew with the highest specific growth rate (0.28 h-1) and Orange II decolorization rate (0.47 h-1). The maximum specific growth rate of biomass (μmax) and the halfsaturation coefficient (KS) under optimal conditions were 0.25 h-1 and 1.5 g.l-1, respectively. The kinetics of decolorization indicated that the process followed first order kinetics with respect to the initial concentration of Orange II. The inhibition constant (KI) was found to be 750 mg l-1 Orange II, indicating that Orange II concentration at e” 750 mg l-1 would inhibit bacterial growth to decolorize Orange II..

Products of Orange II Biodegradation by Enterococcus faecalis ID6017 and Chryseobacterium indologenes ID6016

Microbiology Indonesia Vol 1, No 2 (2007): August 2007
Publisher : Indonesian Society for microbiology

Show Abstract | Original Source | Check in Google Scholar

Abstract

Chryseobacterium indologenes and Enterococcus faecalis were isolated from activated sludge of textile wastewater treatment plant. These bacteria had the ability to decolorize several azo-dyes. Degradation of azo dyes was initiated by decolorization (reduction of azo bond) which occurred in anaerobic condition. In this study, we focussed on biodegradation of Orange II by pure culture of C. indologenes ID6016 and E. faecalis ID6017, and to determine the metabolite products of Orange II degradation. The degradation of Orange II by both bacteria was carried out in batch experiments using liquid medium containing 80 mg/l Orange II, under sequential static agitated incubation. During the bacterial growth under static incubation (6 h), 66.1 mg/l Orange II were decolorized by 35.54 mg/l biomass of E. faecalis ID6017, but no decolorization found with C. indologenes ID6016. Based on HPLC results, the decolorized Orange II products were identified as sulfanilic acid and amino-naphthol. These metabolites were probably used or degraded by C. indologenes ID6016 under agitated incubation.

KAJIAN ANALISIS TERMAL KITIN-KITOSAN CANGKANG UDANG MENGGUNAKAN THERMOGRAVIMETRIC ANALYSIS DAN DIFFERENTIAL THERMAL ANALYSIS (TGA-DTA)

Jurnal Sains dan Terapan Kimia Vol 2, No 2 (2008)
Publisher : Jurnal Sains dan Terapan Kimia

Show Abstract | Original Source | Check in Google Scholar

Abstract

Telah dilakukan kajian analisis termal pada kitin-kitosan cangkang udangmenggunakan thermogravimetric analysis dan differential thermal analysis (TGA-DTA).Kitosan dengan derajat deasetilasi (DD) bervariasi diperoleh dari proses deastilasi kitindengan kondisi percobaan yang berbeda. Kitin dan kitosan dengan variasi DD tersebutdianalisis menggunakan TGA-DTA.Berdasarkan perbedaan termogram TGA-DTA kitin dan kitosan, menunjukkanbahwa kitosan lebih higroskopis daripada kitin dan memiliki gugus asetil yang lebihsedikit. Pada proses deasetilasi, kitin dimungkinkan terjadi degradasi rantai polimer danpembentukan rantai polimer yang lebih panjang secara acak sehingga heterogenitaspolimer kitosan lebih besar daripada kitin.Kata kunci: kitin-kitosan, analisis termal, termogram TGA/DTA

Analisis Isi Berita Pembangunan Periklanan dan Kelautan pada Surat Kabar Kaltim Post

Jurnal Ilmu Komunikasi Vol 5, No 2 (2008)
Publisher : Jurnal Ilmu Komunikasi

Show Abstract | Original Source | Check in Google Scholar

Abstract

Abstract: The objectives of this research were to explain the characteristic of the newspaper’s profile of fishery and marine development, to compare the objectiveity of the reports based on the result of censuses of fishery and marine science and mass media experts’ opinions, to study the policy of news on fishery and marine development on Kaltim Post newspaper editorial staff. The respondents were chosen by using purposive sampling method and were supported by disproportional stratifed random sampling method for news sample clipped for evaluation from the panelist expert team. The data obtained was then analyszed by using content analysist method. The research findings show that the subject matter proportion frequency and volume are mainly dominated with news on marketing and the type of writing is dominated with news, it is also dominated with positive tendencies and non-headlines. The panelist expert team and the mass media expert gave much kind of opinion to the news. Based on the census result, the news is presented enough objectively. The reseacrh findings show that news on fishery and marine development is still considered as a minor discourse by Kaltim Post.

METHANE EMISSION FROM DIRECT SEEDED RICE UNDER THE INFLUENCES OF RICE STRAW AND NITRIFICATION INHIBITOR

Indonesian Journal of Agricultural Science Vol 13, No 1 (2012): April 2012
Publisher : Indonesian Agency for Agricultural Research and Development - MOA

Show Abstract | Original Source | Check in Google Scholar

Abstract

Incorporation of rice straw into soil is a common practice to improve soil productivity and increase inorganic fertilizer availability. However, this practice could contribute to methane (CH4) emission; one of the greenhouse gases that causes global warming. Nitrification inhibitors such as neem cake and carbofuran may reduce methane emission following application of rice straw. The study aimed to evaluate the application of rice straw and nitrification inhibitor to methane emission in rainfed lowland rice system. A factorial randomized block design was used with three replications. The first factor was rice straw incorporation (5 t ha-1 fresh straw, 5 t ha-1 composted straw), and the second factor was nitrification inhibitor application (20 kg ha-1 neem cake, 20 kg ha-1 carbofuran). The experiment was conducted at rainfed lowland in Pati, Central Java, during 2009/2010 wet season. Ciherang variety was planted as direct seeded rice with spacing of 20 cm x 20 cm in each plot of 4 m x 5 m. The rice straw was treated together with soil tillage, whereas nitrification inhibitor was applied together with urea application. Parameters observed were methane flux, plant height, plant biomass, grain yield, organic C content, and bacterial population in soil. The methane flux and soil organic C were measured at 25, 45, 60, 75, and 95 days after emergence. The results showed that composted rice straw incorporation significantly emitted methane lower (73.2 ± 6.6 kg CH4 ha-1 season-1) compared to the fresh rice straw (93.5 ± 4.0 CH4 ha-1 season-1). Application of nitrification inhibitors neem cake and carbofuran reduced methane emission as much as 20.7 and 15.4 kg CH4 ha-1 season-1, respectively. Under direct seeded rice system, methane flux level correlated with plant biomass as shown by linear regression of Y = 0.0015 X + 0.0575 (R2 = 0.2305, n = 27). This means that higher plant biomass produced more methane flux. The study indicates that application of nitrification inhibitors such as neem cake is prospective in decreasing methane emission from direct seeded rice cropping. 

NITROUS OXIDE EMISSION AND NITROGEN UPTAKE AFFECTED BY SOIL AMENDMENT AND NEMATICIDE IN RAINFED RICE SOILS AT CENTRAL JAVA

Indonesian Journal of Agricultural Science Vol 14, No 2 (2013): October 2013
Publisher : Indonesian Agency for Agricultural Research and Development - MOA

Show Abstract | Original Source | Check in Google Scholar

Abstract

Rice cultivation is one of the antropogenic sources of nitrous oxide (N2O) emission that is produced by microbiological nitrification-denitrification processes. Incorporating soil amendment in rainfed rice soil attempted to increase soil productivity, while nematicide application aimed to maintain root growth system. Incorporating soil amendment and nematicide application are predicted to suppress N2O production in lowland rice. The objective of this research was to study the interaction of soil organic amendment and nematicide on N2O emission and nitrogen uptake from rainfed lowland rice soils. A field experiment was conducted in rainfed lowland rice soils during 2010/2011 wet season (direct seeded rice) and 2011 dry season (transplanted rice). The 3 x 3 factorial trial was arranged in a randomized completely block design with three replications. The first factor was soil amendment consisted of without rice straw, fresh rice straw and composted rice straw. The second factor was nematicide application consisted of without nematicide, neemcake and carbofuran. Variables measured were N2O flux, rice grain yield and nitrogen uptake. Incorporation of fresh and composted rice straws reduced N2O flux about 49.2% and 59.9% in transplanted rice, and 32.9% and 28.2% in direct seeded rice, respectively. The neemcake application reduced N2O emission about 44-50%, while carbofuran application decreased N2O emission by 23-35%. Neemcake has a good potential as nitrification inhibitor of N2O emission, so the neem trees have a prospect to be cultivated intensively. The reduction of N2O emission was effective in direct seeded rice system with the application of neemcake and fresh rice straw, however, in transplanted rice system it was effective with neemcake and composted rice straw applications.

UTILISASI TiO2-ZEOLIT DAN SINAR UV UNTUK FOTODEGRADASI ZAT WARNA CONGO RED

Berkala Ilmiah MIPA Vol 16, No 3 (2006)
Publisher : FMIPA UGM

Show Abstract | Original Source | Check in Google Scholar

Abstract

An investigation of Congo Red photodegradation using TiO2-zeolite and uv radiation was performed. TiO2-zeolite was prepared by dispersing of pillaring solution (in form oligocations of titanium) into suspension of zeolite. The suspension was stirred and then filtered to separate the solid phase from the filtrate. The solid phase was calcined by microwave oven at 800 Watt for 5 minutes to convert the oligocations into its oxide forms. The calcined product and unmodified zeolite were characterized using x-ray diffractometry, FT-IR spectrophotometry, X-ray fluorescence and gas sorption analysis to determine their physicochemical properties. Photocatalytic activity of TiO2-zeolite was tested on Congo Red using following method: 50 mg of zeolite was dispersed into 25 mL of 10-4 M Congo Red. The dispersion was irradiated using 365 nm uv light at room temperature on various irradiation times, i.e. 10,20,30,40 and 60 minutes. At certain irradiation time, the dispersion was filtered and the filtrate was then analyzed its concentration using uv-vis spectrophotometry method. Characterization results exhibited that the formation of TiO2 on internal as well as external surfaces of zeolite could not be detected with x-ray diffractometry and FT-IR spectrophotometry, however determination of titanium using x-ray fluorescence analysis on the calcined product showed that the concentration of titanium was much higher than zeolite (0.22% on zeolite and 12.08% on TiO2-zeolite). Gas sorption surface area (16,31 m2/g on zeolite and 100,96 m2/g on tiO2-zeolite) as well as total pore volume of calcined product (13,34 mL/A/g on zeolite and 57,54 mL/A/g on TiO2-zeolite). Photocalytic activity test result conducted on that dye showed that ca 99% of Congo Red was degraded by the system TiO2-zeolite after uv irradiation for 60 minutes. Keywords : TiO2-zeolite, Photocatalytic, UV-irradiation, Congo Red