scholarly journals Characteristics of Diurnal Rainfall over Peatland Area of South Sumatra, Indonesia

2020 ◽  
Vol 5 (4) ◽  
pp. 136
Author(s):  
Puad Maulana Mandailing ◽  
Wijaya Mardiansyah ◽  
Muhammad Irfan ◽  
Arsali Arsali ◽  
Iskhaq Iskandar
Keyword(s):  
Seasonal Variation ◽  
Early Morning ◽  
Temporal Variations ◽  
In Situ Observation ◽  
Peak Time ◽  
The South ◽  
Night Time ◽  
Late Night ◽  
Diurnal Rainfall

The peak time of rainfall occurrence over an area has certain characteristics in which the difference in time and intensity of rainfall varies depending on its location and distance from the sea. This variation can be determined based on the phase and amplitude obtained using harmonic analysis. In this study, combined data from in-situ observation, satellite remote sensing and reanalysis were used to analyze spatial and temporal variations of peak rainfall events over peatland area of the South Sumatra Province. The results show that most of the South Sumatra Province has a diurnal peak of rainfall during afternoon ranging from 16.00 to 19.00 Western Indonesian Time. In addition, the results also indicate that the analysis on the in situ data revealed seasonal variation both in amplitude and time of maximum diurnal rainfall, while the reanalysis data only indicated a weak seasonal variation on the amplitude of the diurnal rainfall. Furthermore, spatial analysis shows that the time of maximum diurnal rainfall has spatial variation. Over the ocean, the time of maximum diurnal rainfall occurs during night time/early morning. Over the lowland or coastal area, the time of maximum diurnal rainfall occurs during afternoon, while over the high altitude (mountain) it occurs during late night.

First in-situ observation of night-time F region currents with the CHAMP satellite

2002 ◽  
Vol 29 (10) ◽  
pp. 127-1-127-4 ◽  
Author(s):  
H. Lühr ◽  
S. Maus ◽  
M. Rother ◽  
D. Cooke
Keyword(s):  
In Situ Observation ◽  
Night Time ◽  
Champ Satellite ◽  
F Region

scholarly journals Uncertainties in SOA simulations due to meteorological uncertainties in Mexico City during MILAGRO-2006 field campaign

2012 ◽  
Vol 12 (7) ◽  
pp. 16293-16326
Author(s):  
N. Bei ◽  
G. Li ◽  
L. T. Molina
Keyword(s):  
Wind Speed ◽  
Mexico City ◽  
Initial Conditions ◽  
Early Morning ◽  
Temporal Variations ◽  
Basis Set ◽  
Peak Time ◽  
Field Campaign ◽  
Ensemble Simulations ◽  
Ensemble Mean

Abstract. The purpose of the present study is to investigate the uncertainties in simulating secondary organic aerosol (SOA) in Mexico City metropolitan area (MCMA) due to meteorological initial uncertainties using the WRF-CHEM model through ensemble simulations. The simulated periods (24 and 29 March 2006) represent two typical meteorological episodes ("Convection-South" and "Convection-North", respectively) in the Mexico City basin during the MILAGRO-2006 field campaign. The organic aerosols are simulated using a non-traditional SOA model including the volatility basis-set modeling method and the contributions from glyoxal and methylglyoxal. Model results demonstrate that uncertainties in meteorological initial conditions have significant impacts on SOA simulations, including the peak time concentrations, the horizontal distributions, and the temporal variations. The ensemble spread of the simulated peak SOA at T0 can reach up to 4.0 &microg m−3 during the daytime, which is around 35% of the ensemble mean. Both the basin wide wind speed and the convergence area affect the magnitude and the location of the simulated SOA concentrations inside the Mexico City basin. The wind speed, especially during the previous midnight and the following early morning, influences the magnitude of the peak SOA concentration through ventilation. The surface horizontal convergence zone generally determines the area with high SOA concentrations. The magnitude of the ensemble spreads may vary with different meteorological episodes but has same significance compared to the ensemble mean.

scholarly journals Uncertainties in SOA simulations due to meteorological uncertainties in Mexico City during MILAGRO-2006 field campaign

2012 ◽  
Vol 12 (23) ◽  
pp. 11295-11308 ◽  
Author(s):  
N. Bei ◽  
G. Li ◽  
L. T. Molina
Keyword(s):  
Wind Speed ◽  
Mexico City ◽  
Initial Conditions ◽  
Early Morning ◽  
Temporal Variations ◽  
Basis Set ◽  
Peak Time ◽  
Ensemble Spread ◽  
Field Campaign ◽  
Ensemble Mean

Abstract. The purpose of the present study is to investigate the uncertainties in simulating secondary organic aerosol (SOA) in Mexico City metropolitan area (MCMA) due to meteorological initial uncertainties using the WRF-CHEM model through ensemble simulations. The simulated periods (24 and 29 March 2006) represent two typical meteorological episodes ("Convection-South" and "Convection-North", respectively) in the Mexico City basin during the MILAGRO-2006 field campaign. The organic aerosols are simulated using a non-traditional SOA model including the volatility basis-set modeling method and the contributions from glyoxal and methylglyoxal. Model results demonstrate that uncertainties in meteorological initial conditions have significant impacts on SOA simulations, including the peak time concentrations, the horizontal distributions, and the temporal variations. The ensemble spread of the simulated peak SOA at T0 can reach up to 4.0 μg m−3 during the daytime, which is around 35% of the ensemble mean. Both the basin wide wind speed and the convergence area affect the magnitude and the location of the simulated SOA concentrations inside the Mexico City basin. The wind speed, especially during the previous midnight and the following early morning, influences the magnitude of the peak SOA concentration through ventilation. The surface horizontal convergence zone generally determines the area with high SOA concentrations. The magnitude of the ensemble spreads may vary with different meteorological episodes but the ratio of the ensemble spread to mean does not change significantly.

scholarly journals In-situ observation of MH formation/decomposition in unconsolidated sands recovered from the South China Sea

2019 ◽  
Vol 158 ◽  
pp. 5433-5438
Author(s):  
Ronghui Sun ◽  
Zhen Fan ◽  
Mingjun Yang ◽  
Jiafei Zhao ◽  
Yongchen Song
Keyword(s):  
South China Sea ◽  
South China ◽  
The South China Sea ◽  
In Situ Observation ◽  
The South ◽  
China Sea ◽  
Unconsolidated Sands

scholarly journals Temporal Variations of Atmospheric CO2 in Dehradun, India during 2009

2013 ◽  
Vol 6 ◽  
pp. ASWR.S10590 ◽  
Author(s):  
Neerja Sharma ◽  
Rabindra K Nayak ◽  
Vinay K Dadhwal ◽  
Yogesh Kant ◽  
Meer M Ali
Keyword(s):  
Large Scale ◽  
Monsoon Season ◽  
Early Morning ◽  
Temporal Variations ◽  
Mixing Ratio ◽  
Night Time ◽  
Local Pollution ◽  
Mixing Ratios ◽  
Casa Model ◽  
Vegetation Activity

The present study reports the temporal variations of CO2 mixing ratio measured using Vaisala GMP-343 sensor (at 15 m height) in Dehradun (30.1 °N, 77.4 °E) during 2009. Being a valley station, the mixing ratios are controlled by biospheric processes but not by large scale transport phenomenon or local pollution. A distinct diurnal cycle varies from 317.9 ppm in the afternoon to 377.2 ppm in the morning (before sunrise). The minimum early morning (0700-1000 IST) drop and minimum afternoon (1300-1700 IST) trough observed during monsoon months are related to the enhanced vegetation activity due to rain at the site. The maximum night time (2200 IST to next day 0700 IST) build up of CO2 observed during monsoon season is associated with the increase in heterotrophic respiration due to high moisture content in the soil. This is also confirmed by the positive coherence between night time CO2 mixing ratio with soil respiration simulated from Carnagie-Ames-Standford Approach (CASA) model. The strong negative coherence with net ecosystem productivity (simulated from the same model) shows that observations captured the regional changes in emission and uptake of CO2 in atmosphere.

scholarly journals Chronopharmaceutical Drug Delivery Systems: A Comprehensive Review

2021 ◽  
Vol 69 (2) ◽  
Author(s):  
Vipin Gupta ◽  
Prashant Kumar
Keyword(s):  
Drug Delivery ◽  
Circadian Rhythms ◽  
Drug Delivery Systems ◽  
Early Morning ◽  
Internal Clock ◽  
Delivery Systems ◽  
The Body ◽  
Peak Time ◽  
Night Time ◽  
Pharmaceutical Dosage Forms

Chronopharmaceutical drug delivery systems release drug at a rhythm that ideally matches the biological requirement of a given disease therapy or prevention. The sound knowledge of the biological processes and their functions utilized in biomedical and pharmaceutical sciences is necessary for effective design and evaluation of pharmaceutical dosage forms. Circadian phase master the circadian clock of the body, the supra chiasmatic nucleus is known to regulate the endogenous circadian rhythms present inside the human body and the peak evidences of some diseases are reported as per circadian rhythm. The secretion of melatonin, a hormone, released by the pineal gland during darkness, help to reset the internal clock, which regulates the timing of different body functions. In certain diseases like asthma, airway resistance increases progressively in early morning, also release of adrenaline and noradrenaline in the morning causes rise in the blood pressure. In hypercholesterolemia, cholesterol synthesis is higher during the night time than day light; in diabetes mellitus blood sugar level is higher in the day time; myocardial insufficiency occurs early in the morning, and many others. The present review addresses the approaches to chronopharmaceuticals, identifies existing technologies, and study of recent chronopharmaceutical drug delivery systems for management of various chronic diseases like diabetes, hypertension and various types of cancers according to the circadian rhythms of diseases in order to optimize therapeutic outcomes and reduce side effects. Recently chronopharmaceutical drug delivery systems are attaining huge importance in the field of pharmaceutical technology for product development because they are proved to reduce dosing frequency, toxicity and also they deliver the drug in particular disease as and when required considering the peak time of the disease, offering better patient compliance.

Toward a Mesoscale Hydrological and Marine Meteorological Observation Network in the South China Sea

2015 ◽  
Vol 96 (7) ◽  
pp. 1117-1135 ◽  
Author(s):  
Lei Yang ◽  
Dongxiao Wang ◽  
Jian Huang ◽  
Xin Wang ◽  
Lili Zeng ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Dynamic Characteristics ◽  
The South China Sea ◽  
In Situ Observation ◽  
Meteorological Observation ◽  
The South ◽  
China Sea ◽  
Observation Network

Abstract Air–sea interaction in the South China Sea (SCS) has direct impacts on the weather and climate of its surrounding areas at various spatiotemporal scales. In situ observation plays a vital role in exploring the dynamic characteristics of the regional circulation and air–sea interaction. Remote sensing and regional modeling are expected to provide high-resolution data for studies of air–sea coupling; however, careful validation and calibration using in situ observations is necessary to ensure the quality of these data. Through a decade of effort, a marine observation network in the SCS has begun to be established, yielding a regional observatory for the air–sea synoptic system. Earlier observations in the SCS were scarce and narrowly focused. Since 2004, an annual series of scientific open cruises during late summer in the SCS has been organized by the South China Sea Institute of Oceanology (SCSIO), carefully designed based on the dynamic characteristics of the oceanic circulation and air–sea interaction in the SCS region. Since 2006, the cruise carried a radiometer and radiosondes on board, marking a new era of marine meteorological observation in the SCS. Fixed stations have been established for long-term and sustained records. Observations obtained through the network have been used to study regional ocean circulation and processes in the marine atmospheric boundary layer. In the future, a great number of multi-institutional, collaborative scientific cruises and observations at fixed stations will be carried out to establish a mesoscale hydrological and marine meteorological observation network in the SCS.

In Situ Observation of Catalyzed Gasification of Graphite by Nickel

1981 ◽  
Vol 39 ◽  
pp. 76-77
Author(s):  
R. T. K. Baker ◽  
R. D. Sherwood
Keyword(s):  
Objective Lens ◽  
In Situ Observation ◽  
Gas Flows ◽  
Catalytic Gasification ◽  
Television Camera ◽  
Viewing Screen ◽  
Fuels And Chemicals ◽  
Gasification Of Carbon ◽  
Transmission Microscope

The catalytic gasification of carbon at high temperature by microscopic size metal particles is of fundamental importance to removal of coke deposits and conversion of refractory hydrocarbons into fuels and chemicals. The reaction of metal/carbon/gas systems can be observed by controlled atmosphere electron microscopy (CAEM) in an 100 KV conventional transmission microscope. In the JEOL gas reaction stage model AGl (Fig. 1) the specimen is positioned over a hole, 200μm diameter, in a platinum heater strip, and is interposed between two apertures, 75μm diameter. The control gas flows across the specimen and exits through these apertures into the specimen chamber. The gas is further confined by two apertures, one in the condenser and one in the objective lens pole pieces, and removed by an auxiliary vacuum pump. The reaction zone is <1 mm thick and is maintained at gas pressure up to 400 Torr and temperature up to 1300<C as measured by a Pt-Pt/Rh 13% thermocouple. Reaction events are observed and recorded on videotape by using a Philips phosphor-television camera located below a hole in the center of the viewing screen. The overall resolution is greater than 2.5 nm.

In situ observation of the martensitic transformation in (Mg,Y)-PSZ

1986 ◽  
Vol 44 ◽  
pp. 500-501
Author(s):  
R-R. Lee
Keyword(s):  
Martensitic Transformation ◽  
High Strength ◽  
Nucleation And Growth ◽  
In Situ Observation ◽  
Considerable Potential ◽  
Transmission Electron ◽  
Structural Applications ◽  
Applied Stresses ◽  
Kinetics Of

Partially-stabilized ZrO2 (PSZ) ceramics have considerable potential for advanced structural applications because of their high strength and toughness. These properties derive from small tetragonal ZrO2 (t-ZrO2) precipitates in a cubic (c) ZrO2 matrix, which transform martensitically to monoclinic (m) symmetry under applied stresses. The kinetics of the martensitic transformation is believed to be nucleation controlled and the nucleation is always stress induced. In situ observation of the martensitic transformation using transmission electron microscopy provides considerable information about the nucleation and growth aspects of the transformation.

In situ TEM observations of melting in nanosized eutectic Pb-Cd inclusions embedded in Al

1996 ◽  
Vol 54 ◽  
pp. 986-987
Author(s):  
S. Hagège ◽  
U. Dahmen ◽  
E. Johnson ◽  
A. Johansen ◽  
V.S. Tuboltsev
Keyword(s):  
Electron Microscope ◽  
Melt Spinning ◽  
Ternary Alloys ◽  
Solid Matrix ◽  
Eutectic System ◽  
In Situ Tem ◽  
In Situ Observation ◽  
Orientation Relationships ◽  
Transmission Electron

Small particles of a low-melting phase embedded in a solid matrix with a higher melting point offer the possibility of studying the mechanisms of melting and solidification directly by in-situ observation in a transmission electron microscope. Previous studies of Pb, Cd and other low-melting inclusions embedded in an Al matrix have shown well-defined orientation relationships, strongly faceted shapes, and an unusual size-dependent superheating before melting.[e.g. 1,2].In the present study we have examined the shapes and thermal behavior of eutectic Pb-Cd inclusions in Al. Pb and Cd form a simple eutectic system with each other, but both elements are insoluble in solid Al. Ternary alloys of Al (Pb,Cd) were prepared from high purity elements by melt spinning or by sequential ion implantation of the two alloying additions to achieve a total alloying addition of up to lat%. TEM observations were made using a heating stage in a 200kV electron microscope equipped with a video system for recording dynamic behavior.

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