Field Study on Pump Vibration and ISO’s New Criteria

1999 ◽  
Vol 121 (4) ◽  
pp. 798-803 ◽  
Author(s):  
Toshiyuki Osada ◽  
Takashi Kawakami ◽  
Tadashi Yokoi ◽  
Yoshinobu Tsujimoto
Keyword(s):  
Rotational Speed ◽  
Work Group ◽  
Field Measurements ◽  
Rotating Machinery ◽  
International Organization ◽  
Vibration Level ◽  
Term Operation ◽  
New Criteria

ISO 10816-3 (a new standard of International Organization for Standardization) was established as vibration criteria for industrial rotating machinery based on the bearing housing vibration in situ. The appropriateness of the application of the proposed vibration criteria to pumps was discussed and studied by a work group in Japan. For the assessment, the data of vibration level in field were measured, and the effects of driver output, rotational speed, and pump type were studied. This paper describes the applicability of the new ISO criteria to the evaluation of vibration level of pumps, based on the results of the field measurements. It was found that the new boundaries of evaluation zones, which are acceptable for unrestricted long-term operation of pumps, are quite appropriate and satisfactory.

Characteristics of natural neutron radiation background performed within the BSUIN project.

2020 ◽  
Author(s):  
Karol Jedrzejczak ◽  
Marcin Kasztelan ◽  
Jacek Szabelski ◽  
Przemysław Tokarski ◽  
Jerzy Orzechowski ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Background Radiation ◽  
Neutron Radiation ◽  
Radiation Background ◽  
Term Operation ◽  
Baltic Sea Region ◽  
Wide Range ◽  
The Baltic

<p>The BSUIN (Baltic Sea Underground Innovation Network) aims to enhance the accessibility of the underground laboratories in the Baltic Sea region for innovation, business and science. One of the BSUIN project activities is characterization of natural background radiation (NBR) in underground facilities. A specific type of NRB is neutron radiation, whose measurement requires specific instruments and long-term exposure in-situ, in heavy underground conditions.</p><p>In this talk the method of natural neutron radiation background will be presented as well as results of pilot measurements in several underground locations. In order to make this measurements, a measuring setup was designed and made. The setup design is closely matched to the task: the setup is scalable in a wide range, completely remotely controlled (via the Internet) and capable of long-term operation (months).</p><p>The pilot measurements were performed in Callio Lab, Pyhäsalmi, Finland, (4100 m w.e.), in Reiche Zeche mine in Freiberg, Germany (410 m w.e.) and in Experimental Mine “Barbara” in Mikołów, Poland (100 m w.e).</p>

Ammonium removal from groundwater using a zeolite permeable reactive barrier: a pilot-scale demonstration

2014 ◽  
Vol 70 (9) ◽  
pp. 1540-1547 ◽  
Author(s):  
Shengpin Li ◽  
Guoxin Huang ◽  
Xiangke Kong ◽  
Yingzhao Yang ◽  
Fei Liu ◽  
...  
Keyword(s):  
Sustainable Use ◽  
Pilot Scale ◽  
Field Application ◽  
Permeable Reactive Barrier ◽  
Capacity Limits ◽  
Term Operation ◽  
Reactive Barrier ◽  
N Removal

In situ remediation of ammonium-contaminated groundwater is possible through a zeolite permeable reactive barrier (PRB); however, zeolite's finite sorption capacity limits the long-term field application of PRBs. In this paper, a pilot-scale PRB was designed to achieve sustainable use of zeolite in removing ammonium (NH4+-N) through sequential nitrification, adsorption, and denitrification. An oxygen-releasing compound was added to ensure aerobic conditions in the upper layers of the PRB where NH4+-N was microbially oxidized to nitrate. Any remaining NH4+-N was removed abiotically in the zeolite layer. Under lower redox conditions, nitrate formed during nitrification was removed by denitrifying bacteria colonizing the zeolite. During the long-term operation (328 days), more than 90% of NH4+-N was consistently removed, and approximately 40% of the influent NH4+-N was oxidized to nitrate. As much as 60% of the nitrate formed in the PRB was reduced in the zeolite layer after 300 days of operation. Removal of NH4+-N from groundwater using a zeolite PRB through bacterial nitrification and abiotic adsorption is a promising approach. The zeolite PRB has the advantage of achieving sustainable use of zeolite and immediate NH4+-N removal.

scholarly journals Application of permeable reactive barrier in groundwater remediation

2019 ◽  
Vol 136 ◽  
pp. 06021
Author(s):  
Qianfeng He ◽  
Shihui Si ◽  
Jun Yang ◽  
Xiaoyu Tu
Keyword(s):  
Groundwater Remediation ◽  
Low Cost ◽  
Structure Type ◽  
Permeable Reactive Barrier ◽  
Term Operation ◽  
Reactive Barrier ◽  
External Power ◽  
Remediation Design

As a new in-situ remediation of groundwater, compared with the traditional “pump and treat” technology, the permeable reactive barrier (PRB) has the advantages of low cost, no external power, the small disturbance to groundwater, small secondary pollution and long-term operation, this paper introduces the basic concept of PRB, technical principle, structure type, the principle of active materials selection and mechanisms of remediation, design and installation factors, it provides ideas for further research and application of PRB technology in groundwater remediation projects in China.

Seasonal variations of Fo, Fm, and Fv/Fm in an epiphytic population of the lichen Punctelia subrudecta (Nyl.) Krog

2007 ◽  
Vol 39 (6) ◽  
pp. 555-565 ◽  
Author(s):  
Laurence BARUFFO ◽  
Mauro TRETIACH
Keyword(s):  
Central Italy ◽  
Field Measurements ◽  
Climatic Conditions ◽  
Light Regime ◽  
Structural Adaptation ◽  
Epiphytic Lichen ◽  
Rapid Changes ◽  
Microclimatic Conditions

Abstract:Chlorophyll a fluorescence was measured every three months from December 2003 to December 2004 in ten, randomly selected thalli of the epiphytic lichen Punctelia subrudecta (Nyl.) Krog occurring in a deciduous, thermophilous downy oak wood in southern Tuscany (central Italy). In situ measurements were carried out with a photosynthesis yield analyser Mini-PAM (Walz, Effeltrich, Germany) on the same measuring points of 30-minute dark-adapted, fully hydrated thalli. The results show a remarkable seasonal change in Fo, Fm, and Fv/Fm, probably caused by a long-term physiological-structural adaptation of the photobiont to the gradual modification of the climatic conditions of each measurement period and the light regime of the understorey. However, P. subrudecta is also sensitive to rapid changes in microclimatic conditions as the PSII functionality is affected by the light regime of the days preceding the field measurements. Some critical observations on the statistical analysis of chlorophyll a fluorescence parameters are also made.

scholarly journals Evaluation of new laser spectrometer techniques for in-situ carbon monoxide measurements

2012 ◽  
Vol 5 (10) ◽  
pp. 2555-2567 ◽  
Author(s):  
C. Zellweger ◽  
M. Steinbacher ◽  
B. Buchmann
Keyword(s):  
Carbon Monoxide ◽  
Measurement Techniques ◽  
Field Measurements ◽  
Current Data ◽  
Atmospheric Composition ◽  
Environmental Research ◽  
Spectroscopic Techniques ◽  
New Techniques

Abstract. Long-term time series of the atmospheric composition are essential for environmental research and thus require compatible, multi-decadal monitoring activities. The current data quality objectives of the World Meteorological Organization (WMO) for carbon monoxide (CO) in the atmosphere are very challenging to meet with the measurement techniques that have been used until recently. During the past few years, new spectroscopic techniques came to market with promising properties for trace gas analytics. The current study compares three instruments that have recently become commercially available (since 2011) with the best currently available technique (Vacuum UV Fluorescence) and provides a link to previous comparison studies. The instruments were investigated for their performance regarding repeatability, reproducibility, drift, temperature dependence, water vapour interference and linearity. Finally, all instruments were examined during a short measurement campaign to assess their applicability for long-term field measurements. It could be shown that the new techniques perform considerably better compared to previous techniques, although some issues, such as temperature influence and cross sensitivities, need further attention.

Research on LED multi-sector stable display model in variable rotational speed

2021 ◽  
pp. 1-11
Author(s):  
Luhong Lang ◽  
Dong Ma ◽  
Jun Dong ◽  
Junming He ◽  
Panpan Xu ◽  
...  
Keyword(s):  
Rotational Speed ◽  
Linear Array ◽  
Noise Pollution ◽  
Frequency Measurement ◽  
Stepping Motor ◽  
Term Operation ◽  
Speed Fluctuation ◽  
Precision Frequency ◽  
The Relationship

To solve the display distortion caused by the motor rotational speed changes in the long-term operation of the rotating LED multi-sector display system，the model for LED multi-sector stable display (MSSD) in variable rotational speed is proposed based on the principle of visual persistence. The stepping motor subdivision driving technology is applied to the rotating LED multi-sector display, and the equal precision frequency measurement method is used for accurate rotational speed measurement. Then the innovation adaptive kalman filter (IAKF) is researched to further enhance the robustness to eliminate noise pollution, and the relationship between the modification value caused by rotational speed and the LED linear array minimum refresh time is analysed. The rotating LED MSSD system based on LED linear array rotated by stepping motor is provided. The test results reveal the relationship between rotational speed and the LED linear array minimum refresh time, and show that the lighting position of the LED can be synchronized with the lighting state during the rotational speed fluctuation, and the error can be controlled to a low level via LED linear array minimum refresh time correction．The designed model can effectively eliminate the distortion of the rotating LED multi-sector display screen caused by the changes of the motor rotational speed, and has a very stable display effect.

scholarly journals Towards a stable and absolute atmospheric carbon dioxide instrument using spectroscopic null method

2013 ◽  
Vol 6 (7) ◽  
pp. 1611-1621 ◽  
Author(s):  
B. Xiang ◽  
D. D. Nelson ◽  
J. B. McManus ◽  
M. S. Zahniser ◽  
S. C. Wofsy
Keyword(s):  
Carbon Dioxide ◽  
Atmospheric Carbon Dioxide ◽  
Field Measurements ◽  
Term Operation ◽  
Long Term Stability ◽  
Atmospheric Carbon ◽  
Carbon Dioxide Co2 ◽  
Stability And Accuracy ◽  
Spectral Null

Abstract. We present a novel spectral method to measure atmospheric carbon dioxide (CO2) with high precision and stability without resorting to calibration tanks during long-term operation. This spectral null method improves precision by reducing spectral proportional noise associated with laser emission instabilities. We employ sealed quartz cells with known CO2 column densities to serve as the permanent internal references in the null method, which improve the instrument's stability and accuracy. A prototype instrument – ABsolute Carbon dioxide (ABC) is developed using this new approach. The instrument has a one-second precision of 0.02 ppm, which averages down to 0.007 ppm within one minute. Long-term stability of within 0.1 ppm is achieved without any calibrations for over a one-month period. These results have the potential for eliminating the need for calibration cylinders for high accuracy field measurements of carbon dioxide.

Targeted filling of silica in Nafion by a modified in situ sol–gel method for enhanced fuel cell performance at elevated temperatures and low humidity

2019 ◽  
Vol 55 (38) ◽  
pp. 5499-5502 ◽  
Author(s):  
Guoxiao Xu ◽  
Shuai Li ◽  
Jing Li ◽  
Zhao Liu ◽  
Ying Li ◽  
...  
Keyword(s):  
Elevated Temperatures ◽  
Sol Gel ◽  
Silica Network ◽  
Fuel Cell Performance ◽  
Term Operation ◽  
Ionic Cluster ◽  
Low Humidity ◽  
The Stability

By facilely utilizing an ionic cluster as a nano-reactor, a silica network can be targeted filled in Nafion to increase the PEMFC performance at elevated temperatures and low humidity. Moreover, the stability of Nafion can be improved for the long-term operation of PEMFC under harsh conditions.

scholarly journals In-flight calibration of double-probe DC electric field measurements on Cluster

2014 ◽  
Vol 4 (1) ◽  
pp. 85-107
Author(s):  
Y. V. Khotyaintsev ◽  
P.-A. Lindqvist ◽  
C. M. Cully ◽  
A. I. Eriksson ◽  
M. André
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Field Measurements ◽  
Calibration Procedure ◽  
Double Probe ◽  
Ac Electric Fields ◽  
Dc Electric Field ◽  
Electric Field Measurements

Abstract. Double-probe electric field instrument with long wire booms is one of the most popular techniques for in situ measurement of DC and AC electric fields in plasmas on spinning spacecraft platforms, which have been employed on a large number of space missions. Here we present an overview of the calibration procedure used for the EFW instrument on Cluster, which involves spin fits of the data and correction of several offsets. We also describe the procedure for the offset determination and present results for the long-term evolution of the offsets.

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