scholarly journals SEBARAN SPASIAL LOGAM Pb, Cd, Cu, Zn DAN FRAKSI GEOKIMIA DI SEDIMEN PERAIRAN PANTAI KOTA MAKASSAR

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Shinta Werorilangi ◽  
Alfian Noor ◽  
M. Farid Samawi ◽  
Ahmad Faizal ◽  
Akbar Tahir
Keyword(s):  
Block Kriging ◽  
Sequential Method

Perairan pantai Kota Makassar, termasuk dua muara sungai yang mengapit, yaitu Sungai Jeneberang dan Sungai Tallo banyak mendapat inputan logam dari badan sungai dan dari daratan utama, berupa limbah industri dan limbah perkotaan.  Penelitian ini bertujuan untuk menentukan distribusi spasial konsentrasi Pb, Cd, Cu, dan Zn serta fraksi bioavailable di sedimen perairan pantai Kota Makassar. Penelitian dilakukan di wilayah perairan pantai Kota Makassar, mulai dari muara Sungai Jeneberang hingga muara Sungai Tallo. Pengukuran logam dilakukan pada sedimen berukuran < 63 μm. Spesiasi logam pada fraksi sedimen ditentukan dengan metode Community Bureau of Reference (BCR) Three-steps Sequential method yang menghasilkan fraksi exchangeable dan acid soluble, reducible, serta oxidisable. Interpolasi sebaran spasial logam di sedimen dilakukan dengan menggunakan teknik Sistem Informasi Geografis (SIG) yaitu block kriging (BK) dengan  program Arc View.  Sebaran logam sangat ditentukan oleh input atau sumber dari daratan dimana sebaran spasial logam Pb, Cd, Cu, dan Zn di sedimen meningkat ke arah utara pantai Kota Makassar.  Sebaran spasial fraksi 1 (terlarut dalam asam, acid reducible) logam Pb dan Cu tidak berbanding lurus dengan sebaran konsentrasi totalnya  di sedimen. Sedangkan sebaran spasial fraksi 1 logam Cd dan Zn berbanding lurus dengan sebaran konsentrasi totalnya di sedimen.

scholarly journals Crystal Engineering Approach for Fabrication of Inverted Perovskite Solar Cell in Ambient Conditions

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1751
Author(s):  
Inga Ermanova ◽  
Narges Yaghoobi Nia ◽  
Enrico Lamanna ◽  
Elisabetta Di Bartolomeo ◽  
Evgeny Kolesnikov ◽  
...  
Keyword(s):  
Solar Cell ◽  
Crystal Engineering ◽  
High Performance ◽  
Perovskite Solar Cells ◽  
Perovskite Solar Cell ◽  
Layer By Layer ◽  
Ambient Conditions ◽  
Sequential Method ◽  
Engineering Approach ◽  
Hole Transporting

In this paper, we demonstrate the high potentialities of pristine single-cation and mixed cation/anion perovskite solar cells (PSC) fabricated by sequential method deposition in p-i-n planar architecture (ITO/NiOX/Perovskite/PCBM/BCP/Ag) in ambient conditions. We applied the crystal engineering approach for perovskite deposition to control the quality and crystallinity of the light-harvesting film. The formation of a full converted and uniform perovskite absorber layer from poriferous pre-film on a planar hole transporting layer (HTL) is one of the crucial factors for the fabrication of high-performance PSCs. We show that the in-air sequential deposited MAPbI3-based PSCs on planar nickel oxide (NiOX) permitted to obtain a Power Conversion Efficiency (PCE) exceeding 14% while the (FA,MA,Cs)Pb(I,Br)3-based PSC achieved 15.6%. In this paper we also compared the influence of transporting layers on the cell performance by testing material depositions quantity and thickness (for hole transporting layer), and conditions of deposition processes (for electron transporting layer). Moreover, we optimized second step of perovskite deposition by varying the dipping time of substrates into the MA(I,Br) solution. We have shown that the layer by layer deposition of the NiOx is the key point to improve the efficiency for inverted perovskite solar cell out of glove-box using sequential deposition method, increasing the relative efficiency of +26% with respect to reference cells.

scholarly journals Industrial Plume Properties Retrieved by Optimal Estimation Using Combined Hyperspectral and Sentinel-2 Data

2021 ◽  
Vol 13 (10) ◽  
pp. 1865
Author(s):  
Gabriel Calassou ◽  
Pierre-Yves Foucher ◽  
Jean-François Léon
Keyword(s):  
Matched Filter ◽  
Estimation Method ◽  
Optimal Estimation ◽  
Model Parameters ◽  
Surface Reflectance ◽  
Sequential Method ◽  
Modal Radius ◽  
Sentinel 2

Stack emissions from the industrial sector are a subject of concern for air quality. However, the characterization of the stack emission plume properties from in situ observations remains a challenging task. This paper focuses on the characterization of the aerosol properties of a steel plant stack plume through the use of hyperspectral (HS) airborne remote sensing imagery. We propose a new method, based on the combination of HS airborne acquisition and surface reflectance imagery derived from the Sentinel-2 Multi-Spectral Instrument (MSI). The proposed method detects the plume footprint and estimates the surface reflectance under the plume, the aerosol optical thickness (AOT), and the modal radius of the plume. Hyperspectral surface reflectances are estimated using the coupled non-negative matrix factorization (CNMF) method combining HS and MSI data. The CNMF reduces the error associated with estimating the surface reflectance below the plume, particularly for heterogeneous classes. The AOT and modal radius are retrieved using an optimal estimation method (OEM), based on the forward model and allowing for uncertainties in the observations and in the model parameters. The a priori state vector is provided by a sequential method using the root mean square error (RMSE) metric, which outperforms the previously used cluster tuned matched filter (CTMF). The OEM degrees of freedom are then analysed, in order to refine the mask plume and to enhance the quality of the retrieval. The retrieved mean radii of aerosol particles in the plume is 0.125 μμm, with an uncertainty of 0.05 μμm. These results are close to the ultra-fine mode (modal radius around 0.1 μμm) observed from in situ measurements within metallurgical plant plumes from previous studies. The retrieved AOT values vary between 0.07 (near the source point) and 0.01, with uncertainties of 0.005 for the darkest surfaces and above 0.010 for the brightest surfaces.

Eliminating accumulation of inrush current with sequential method

2019 ◽  
Author(s):  
Frits E. Sinaga ◽  
Sayyid I. Ibad ◽  
Dany H. Rusman ◽  
Amy H. Salman ◽  
Muhammad I. Arsyad
Keyword(s):  
Inrush Current ◽  
Sequential Method

A modified sequential method used to prepare high quality perovskite on ZnO nanorods

2015 ◽  
Vol 639 ◽  
pp. 283-288 ◽  
Author(s):  
Meijuan Wang ◽  
Shibin Li ◽  
Peng Zhang ◽  
Yafei Wang ◽  
Hangqian Li ◽  
...  
Keyword(s):  
Zno Nanorods ◽  
High Quality ◽  
Sequential Method

Simulation of landscape pattern of old growth forests of Korean pine by block kriging

1997 ◽  
Vol 8 (3) ◽  
pp. 131-136 ◽  
Author(s):  
Wang Zhengquan ◽  
Zhang Yandong ◽  
Wang Qingcheng ◽  
Harbin Li
Keyword(s):  
Landscape Pattern ◽  
Korean Pine ◽  
Block Kriging ◽  
Old Growth ◽  
Old Growth Forests

A sequential method of solving inverse natural convection problems

2002 ◽  
Vol 18 (3) ◽  
pp. 529-546 ◽  
Author(s):  
H M Park ◽  
J S Chung
Keyword(s):  
Natural Convection ◽  
Sequential Method

scholarly journals Comparison of Single and Double-Network PVA Pervaporation Performance: Effect of Operating Temperature

2020 ◽  
Vol 64 (3) ◽  
pp. 377-383
Author(s):  
Asmaa Selim ◽  
András József Tóth ◽  
Enikő Haáz ◽  
Dániel Fózer ◽  
Péter Mizsey
Keyword(s):  
Operating Temperature ◽  
Sorption Process ◽  
Ethanol Solution ◽  
Sequential Method ◽  
Ethanol Mixture ◽  
Performance Effect ◽  
Double Network ◽  
Thermal Crosslinking ◽  
High Ethanol ◽  
And Diffusion

Thermal crosslinking sequential method applied for DN-PVAs generation efficiently. The swelling measurements investigated that the hydrophilicity of the membrane decreases because of the collaboration of the second thermal crosslinked PVA matrix. The dehydration performance of ethanol solution showed improved using the thermal crosslinked double network PVA membrane. The pervaporation dehydration of the water-ethanol mixture was investigated at different conditions. The separation selectivity showed a significant improvement, while the permeation flux declines due to the incorporation of the second PVA network under 95 % ethanol and at 40 °C. Increasing the feed temperature enhanced the permeability of the membrane, while decreasing the water content in the feed resulted in an increase in the selectivity. The overall results showed that, at high operating temperature and high ethanol concentration in the feed, the prepared membranes are highly selective towards the water with reasonable fluxes values. The influence of temperature permeation parameter and diffusion coefficient of the feed component is also discussed. The negative heat of sorption ( ∆Hs ) values calculated on the basis of the estimated Arrhenius activation energy values indicates that the sorption process is controlled by Langmuir's mode.

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