Kajian pengaruh kondisi dekomposisi analisis logam tembaga dalam sedimen di pelabuhan ikan Sendang Biru secara SSA

Cu that is absorbed in marine sediments can accumulate in the food chain even in small concentrations. Cu analysis in these sediments can be used to analyze water pollution due to human activities. The purpose of this study was to determine the level of Cu in decomposed sediments with variation of solvent concentration, variation of decomposition time, and variation of solvent volume and then compare the result of Cu analysis decomposed using HNO3 solvent under effective condition with aqua regia solvent. The method of analysis used is decomposition technique of sediment sample by using reflux and then analyzed with AAS.. Cu yang terserap dalam sedimen laut dapat berakumulasi dalam rantai makanan meskipun dalam konsentrasi kecil. Analisis Cu dalam sedimen ini dapat digunakan untuk menganalisis pencemaran perairan akibat aktivitas manusia. Tujuan penelitian ini adalah menentukan kadar Cu dalam sedimen yang didekomposisi dengan variasi konsentrasi pelarut, variasi waktu dekomposisi, dan variasi volume pelarut dan membandingkan hasil analisis Cu yang didekomposisi menggunakan pelarut HNO3 pada kondisi efektif dengan pelarut akuaregia. Metode analisis yang digunakan yaitu teknik dekomposisi sampel sedimen dengan menggunakan refluks dan dianalisis dengan SSA.

Selective Flamingo Medium for the Isolation of Aspergillus fumigatus

For various studies in the clinic as well as the environment, it is essential to be able to selectively isolate Aspergillus fumigatus from samples containing bacteria as well as various other fungi (mainly Mucorales). Six agar media were compared for effectiveness in selectively isolating Aspergillus fumigatus from agricultural plant waste, woodchip waste, green waste, soil, grass and air samples collected in the Netherlands at a 48 °C incubation. The Flamingo Medium incubated at 48 °C, provided the most effective condition for the isolation of A. fumigatus from environmental samples, since it effectively inhibited the growth of competing fungi (mainly Mucorales) present in the environmental samples. Flamingo Medium reduced the number of colonies of Mucorales species by 95% and recovered an average of 20−30% more A. fumigatus colonies compared to the other media. We further confirmed that Flamingo Medium can inhibit the growth of clinical Mucorales, which occasionally present in patient’s tissue and can also be used for clinical applications. We suggest the use of Flamingo Medium as an efficient method for the study of A. fumigatus from important environmental niches for which there is increasing interest. Additionally, it can also be used in the clinic to isolate A. fumigatus especially from tissue contaminated with Mucorales.

Photoluminescence Spectroscopy Measurements for Effective Condition Assessment of Transformer Insulating Oil

Condition assessment of insulating oil is crucial for the reliable long-term operation of power equipment, especially power transformers. Under thermal aging, critical degradation in oil properties, including chemical, physical, and dielectric properties, occurs due to the generation of aging byproducts. Ultraviolet-visible (UV-Vis) spectroscopy was recently proposed for the condition assessment of mineral oil. However, this absorption technique may involve all electronic states of the investigated material which typically yield a broad spectrum, and thus cannot precisely reflect the electronic structure of aged oil samples. It also cannot be implemented as an online sensor of oil degradation. In this paper, photoluminescence (PL) spectroscopy is introduced, for the first time, for effective condition assessment of insulating oil. The PL technique involves emission processes that only occur between a narrow band of electronic states that are occupied by thermalized electrons and consequently yields a spectrum that is much narrower than that of the absorption spectrum. Aged oil samples with different aging extents were prepared in the laboratory using accelerated aging tests at 120 °C, under which 1 day of laboratory aging is equivalent to approximately 1 year of aging in the field. These aged samples were then tested using PL spectroscopy with a wavelength ranging from 150 nm to 1500 nm. Two main parameters were evaluated for quantitative analysis of PL spectra: The full width at half-maximum and the enclosed area under the PL spectra. These parameters were correlated to the aging extent. In conjunction with PL spectroscopy, the aged oil samples were tested for the dielectric dissipation factor as an indication of the number of aging byproducts. Interestingly, we find a correlation between the PL spectra and the dielectric dissipation factor. The results of PL spectroscopy were compared to those of UV-Vis spectroscopy for the same samples and the parameters extracted from PL spectra were compared to the aging b-products extracted from UV-Vis spectra. Finally, the corresponding physical mechanisms were discussed considering the obtained results and the spectral shift for each spectrum. It was proved that PL spectroscopy is a promising technique for the condition assessment of insulating oil when compared to conventional transformer oil assessment measuring techniques and even to other optical absorption techniques.

KONDISI EFEKTIF PESERTA DIDIK DALAM PROSES PEMBELAJARAN DI SMK MUHAMMADIYAH 4 SURAKARTA

The writing of this scientific article aims to know the effective condition of learners in the learning process at SMK Muhammadiyah 4 Surakarta. These effective conditions are important things that we should be mindful of. Because it is in this condition that students are able to receive science delivered by teachers easily. To achieve this situation, a teacher should take into account what factors affect the learning process, what a student needs during the learning process. So with this research we observe to know what is the effective condition of learners in the learning process. We use qualitative method with direct observation and student interviews in the X-Class of pharmacy at SMK Muhammadiyah 4 Surakarta. The results of this study were obtained that most students and teachers have both applied effective learning conditions.

A Novel Autoencoder with Dynamic Feature Enhanced Factor for Fault Diagnosis of Wind Turbine

Due to the complicated operating environment and variable operating conditions, wind turbines (WTs) are extremely prone to failure and the frequency of fault increases year by year. Therefore, the solutions of effective condition monitoring and fault diagnosis are urgently demanded. Since the vibration signals contain a lot of health condition information, the fault diagnosis based on vibration signals has received extensive attention and achieved impressive progress. However, in practice, the collected health condition signals are very similar and contain a lot of noise, which makes the fault diagnosis of WTs more challenging. In order to handle this problem, this paper proposes a model called denoising stacked feature enhanced autoencoder with dynamic feature enhanced factor (DSFEAE-DF). Firstly, a feature enhanced autoencoder (FEAE) is constructed through feature enhancement so that the discriminative features can be extracted. Secondly, a feature enhanced factor which is independent of manual judgments is proposed and embedded into the training process. Finally, the DSFEAE-DF, combining one noise adding scheme, stacked FEAEs and dynamic feature enhanced factor, is established. Through experimental comparisons, the superiorities of the proposed DSFEAE-DF are verified.

Ultrasound Assisted Sonochemical Decomposition of Methyl Orange in the Presence of H2O2 and CCl4

Methyl orange (MO) is an orange azoic dye; which has transition range from 3.1 to 4.4. Sonochemical decomposition of methyl orange in the presence of H2O2 and CCl4 has given effective result to reclaim water from the effluents released by the industries. The aim of this research was to investigate the effective condition for the decomposition of MO in the presence or absence of additives. For this, 50 mg/L solution of MO was sonicated in the presence and absence of different additives. It was clearly confirmed that the rates of sonochemical decomposition of MO increased with increasing the concentration in both cases of H2O2 and CCl4. The combination of advanced oxidation processes (AOPs) namely hydrogen per-oxide and carbon tetra-chloride with sonolysis harvests the decomposition of wide spectrum of organic contaminants. The combination of sonolysis with H2O2 and CCl4 enhances the production of non-selective radicals to improve the decomposition process. The AOPs is technically feasible and also economic. Based on the results, it was suggested that the rate of MO decomposition can be effectively enhanced by the sonolysis of CCl4 and also for H2O2. It was possible to include order- MO+200 µL H2O2 > MO+100 µL H2O2 > MO+20 µL H2O2 > MO; MO+200 µL CCl4 > MO+100 µL CCl4 > MO+20 µL CCl4 > MO.

Preliminary Research of Possibility of Using Thermovision for Diagnosis and Predictive Maintenance of Marine Engines

Infrared thermography has evolved as an effective condition monitoring tool for real-time temperature monitoring of objects or processes in a noncontact way. This paper presents the results of research conducted with use of infrared camera for monitoring 3AL25/30 engine, especially turbocharger, placed in Marine Engineering Faculty of Gdynia Maritime University. Research was carried out using a thermal camera NEC Thermo Gear G100 with appropriate software. Test results improved that infrared thermography is useful also for monitoring the condition of ship engine equipment, and enable anticipating failures during engine work.

Ukraine: an Example of Limits of Balance and Asymmetric Reaction in the Maritime Trade Market

This article deals with the principles of reaction of shipowners’ structures on the set of changes in the maritime trade market’s parameters. There are features of decision-making within the uncertain variability of the maritime trade market. Thus there are subsystems clearly realizing prioritizing strategies, and subsystems that choose the form of reaction to changes in the conditions of limited resources in the structure of the global maritime transport industry. Maintaining a balance, as the most effective condition of any market, plays a special role in maritime transport due to the high cost of fleet deadweight and the intensity of the crews’ work. Therefore, the clarity and timeliness of the response to external changes in traffic flows and carrying capacity of competing shipping companies becomes paramount.