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"ABSTRAKChelating resin-packed minicolumn preconcentration was used for multielement determination of trace metals in seawater by inductively coupled plasma mass spectrometry (ICP-MS). The chelating resin-packed minicolumn was constructed with two syringe filters (DISMIC 13HP and Millex-LH) and an iminodiacetate chelating resin (Chelex 100, 200-400 mesh), with which trace metals in 50 mL of original seawater sample were concentrated into 0.50 mL of 2 M nitric acid, and then 100-fold preconcentration of trace metals was achieved. Then, 0.50 mL analysis solution was subjected to the multielement determination by ICP-MS equipped with a MicroMist nebulizer for micro-sampling introduction. The preconcentration and elution parameters such as the sample-loading flow rate, the amount of 1 Mammonium acetate for elimination of matrix elements and the amount of 2 M nitric acid for eluting trace metals wasoptimized to obtain good recoveries and analytical detection limits for trace metals. The analytical results for V, Mn, Co, Ni, Cu, Zn, Mo, Cd, Pb, and U in three kinds of seawater certified reference materials (CRMs; CASS-3, NASS-4, and NASS-5) agreed well with their certified values. The observed values of rare earth elements (REEs) in the above seawater CRMs were also consistent with the reference values. Therefore, the compiled reference values for the concentrations of REEs in CASS-3, NASS-4, and NASS-5 were proposed based on the observed values and reference data for REEs in these CRMs. "

"This study reported quantifications of fine particle bound trace metals and their potential health risks for residents in guangzhou, a rapidly developing and most populated city in South China...."

"Ruang ambigu merupakan ruang yang dapat secara bebas diinterpretasikan oleh penggunanya, sehingga berdampak pada kompleksitas makna yang memunculkan penggunaan ruang yang kontradiktif dan bervariasi. Karakteristik ini kemudian termanifestasi dalam bentuk trace. Dalam produksinya, terdapat elemen-elemen seperti enabler material, enabling actor, enabling action, dan interpretasi trace yang berdampak pada bagaimana trace dihasilkan.Dengan demikian, skripsi ini akan mengkaji ruang ambigu melalui keberadaan trace di dalamnya dengan menguraikan trace yang ditemukan sebagai elemen-elemen pembentuk trace, sehingga dapat dipahami bagaimana masing-masing elemen tersebut dapat mengindikasikan ruang ambigu. Dalam prosesnya, studi menghasilkan bahwa masing-masing elemen pembentuk trace yang diuraikan kemudian mampu memberikan indikasi ambiguitas melalui kompleksitas trace dalam enabler material, kontradiksi terhadap enabling action yang dilakukan oleh enabling actor, dan keberagaman respons pengguna terhadap trace di sekitarnya.

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Ambiguous space is a space formed through a free interpretation of space by its users, causing a complexity of meaning that emerges in contradictory and varied use of space. These characteristics are then manifested in the form of traces. In its production, there are elements such as enabler material, enabling actor, enabling action, and trace interpretation that impacts how the trace is formed.

Therefore, this study will examine ambiguous space through the presence of traces in it by deciphering found traces as trace elements so that it can be understood how each of these elements can indicate ambiguous space. In the end, this study shows that each of the forming elements can indicate ambiguity through the complexity of trace on the enabler material, the contradiction of enabling action by enabling actor, and the variety of user responses to the surrounding trace."

"Enzim ligninolitik hasil produksi kapang ataupun bakteri mampu mengurai lignin dalam struktur lignoselulosa tanaman yang sulit terdekomposisi dengan memanfaatkan reaksi redoks sehingga rantai samping maupun gugus fenol dan nonfenol di dalam lignin menjadi terputus. Kapang pelapuk putih telah diketahui memiliki aktivitas enzim ligninolitik yang tinggi. Intervensi ion logam dalam media kultur sedikit banyak mempengaruhi proses transkripsi dan translasi dalam sintesis protein sehingga aktivitas enzim dapat meningkat ataupun menurun. Penelitian ini bertujuan untuk mengetahui pengaruh ion logam atau unsur kelumit dalam media lignoselulosik daun nanas pada kultur kapang C.globosum dan Penicillium sp. terhadap aktivitas enzim ligninolitiknya, terutama lignin peroksidase (LiP) dan mangan peroksidase (MnP), dengan kapang pelapuk putih (T.versicolor dan P.chrysosporium) sebagai pembanding. Aktivitas enzim ditentukan setelah mengukur absorbansi crude enzyme menggunakan spektrofotometer UV. Karakterisasi enzim berupa uji pH optimum dan kinetika enzim dilakukan pada kapang dengan nilai aktivitas lebih tinggi antara C.globosum atau Penicillium sp.. Uji pH optimum dilakukan dengan menentukan aktivitas enzim tertinggi pada pH 3, 4, 5, 6, dan 7 sedangkan profil kinetika enzim ditentukan pada rentang konsentrasi substrat berbeda-beda, yaitu veratril alkohol (6, 7, 8, 9, 10 mM) untuk LiP atau MnSO4 (0,2; 0,4; 0,6; 1 mM) untuk MnP. Dibandingkan dengan C.globosum, enzim LiP dan MnP dari Penicillium sp. yang tidak diintervensi ion logam menunjukkan nilai aktivitas lebih tinggi, yaitu 0,305 U/mL dan 8,341 U/mL. Selanjutnya, enzim LiP dan MnP dari Penicillium sp. dikarakterisasi. pH optimum enzim LiP dan MnP adalah pH 3. Laju reaksi maksimum enzim (Vmaks) MnP adalah 6,7568 μmol.ml-1.menit-1, sedangkan konstanta Michaelis-Mentennya (Km) sebesar 0,3777 μmol.ml-1.

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Ligninolytic enzymes produced by fungi or bacteria are able to break down the structure of lignin in plant lignocellulosic that are difficult to decompose by utilizing redox reaction. The reaction makes lignin’s side chains as well as phenol and nonphenol groups are able to be broken. White-rot fungi has been known to have high ligninolytic enzyme activity. The intervention of metal ions in the culture media affect the transcription and translation of protein synthesis so that the enzyme activity can increase or decrease. This study aimed to determine the effect of metal ions or trace elements in lignocellulosic media of pineapple leaves of the culture of C.globosum and Penicillium sp. on ligninolytic enzyme activity, especially lignin peroxidase (LiP) and manganese peroxidase (MnP), with white-rot fungi (T.versicolor and P.chrysosporium) as the comparison. Enzyme activity was determined after measuring the absorbance of crude enzyme using UV spectrophotometer. Enzyme characterization consisted of optimum pH and enzyme kinetic assay was carried out on fungi with higher activity values between C.globosum and Penicillium sp.. Optimum pH assay was carried out by determining the highest enzyme activity at pH 3, 4, 5, 6, and 7 while the kinetic profile was determined in the range of different substrate concentrations, namely veratryl alcohol (6, 7, 8, 9, 10 mM) for LiP or MnSO4 (0,2; 0,4; 0,6; 1 mM) for MnP. Compared with C.globosum, the LiP and MnP enzymes from Penicillium sp. which was not intervened by metal ions showed higher activity values, which are 0.305 U/mL and 8.341 U/mL. Furthermore, the LiP and MnP enzymes from Penicillium sp. were characterized. The optimum pH for LiP and MnP enzymes from Penicillium sp. is pH 3. The maximum enzyme reaction rate (Vmax) of MnP from Penicillium sp. is 6,7568 mol.ml-1.minute-1, while the Michaelis-Menten constant (Km) is 0.3777 mol.ml-1."