A simple and rapid visual method for the determination of ammonia nitrogen in environmental waters using thymol

1999 ◽  
Vol 365 (5) ◽  
pp. 0467 ◽  
Author(s):  
M. Okumura ◽  
K. Fujinaga ◽  
Y. Seike ◽  
S. Honda
Keyword(s):  
Ammonia Nitrogen ◽  
Environmental Waters ◽  
Visual Method

An “on–off” fluorescent probe based on cucurbit[7]uril for highly sensitive determination of ammonia nitrogen in aquaculture water

2021 ◽  
Author(s):  
Zhen Li ◽  
Tan Wang ◽  
Xianbao Xu ◽  
Cong Wang ◽  
Daoliang Li
Keyword(s):  
Fluorescence Quenching ◽  
Inclusion Complex ◽  
Fluorescent Probe ◽  
Ammonia Nitrogen ◽  
Highly Sensitive ◽  
Sensitive Determination ◽  
Aquaculture Water

A novel “on–off” fluorescent probe for the determination of ammonia nitrogen has been synthesized. URO can replace PAL into the cavity of CB[7] to form a stable inclusion complex, eventually forming the fluorescence quenching system of URO@CB[7].

Kinetic fluorimetric determination of trace hydrazine in environmental waters

2006 ◽  
Vol 86 (13) ◽  
pp. 995-1005 ◽  
Author(s):  
Jing Fan ◽  
Jichuan Kong ◽  
Suling Feng ◽  
Jianji Wang ◽  
Pingan Peng
Keyword(s):  
Environmental Waters ◽  
Fluorimetric Determination

scholarly journals Determination of dimethoate, 2,4-dichlorophenoxy acetic acid, mecoprop and linuron pesticides in environmental waters in Republic of Macedonia by high performance liquid chromatography

2008 ◽  
Vol 27 (1) ◽  
pp. 25 ◽  
Author(s):  
Aleksandra Nestorovska-Krsteska ◽  
Meri Mirčeska ◽  
Jean-Jacques Aaron ◽  
Zoran Zdravkovski
Keyword(s):  
Acetic Acid ◽  
Solid Phase Extraction ◽  
High Performance ◽  
Solid Phase ◽  
Sampling Period ◽  
Phase Extraction ◽  
Environmental Waters ◽  
Spe Method ◽  
Dichlorophenoxy Acetic Acid

An HPLC-UVDAD method for determination of dimethoate, 2,4-dichlorophenoxy acetic acid (2,4-D), mecoprop (MCPP) and linuron in environmental waters was developed. The water samples were concentrated and extracted by a solid phase extraction (SPE) method on Bond Elut PPL cartridges. After extraction the investigated compounds were separated on Stability RP Pesticides chromatographic column using mobile phase composed of acetonitrile- water-acetic acid in volume fractions of 39:59:2 and flow rate of 0.7 mL/min. Ultraviolet absorption detection was carried out for dimethoate, 2,4-D and MCPP at 229 nm, and for linuron at 249 nm. Recoveries made from 500 mL of drinking waters using solid phase extraction ranged between 64.3–92.1 %. The method was applied to environmental waters in Macedonia that receive runoffs from agriculture lands. The levels of pesticides under study ranged between 0.31 μg/L and 7.05 μg/L, depending on the compound and sampling period.

scholarly journals Construction and evaluation of an automated flow injection-stopped flow analyser for multipoint reaction rate spectrophotometric methods. Determination of ammonia nitrogen, creatinine and phosphate

1991 ◽  
Vol 13 (5) ◽  
pp. 199-207 ◽  
Author(s):  
Constantinos A. Georgiou ◽  
Michael A. Koupparis
Keyword(s):  
Flow Injection ◽  
Reaction Rate ◽  
Assembly Language ◽  
Ammonia Nitrogen ◽  
Stopped Flow ◽  
Data Sampling ◽  
Ramp Generator ◽  
Spectrophotometric Methods ◽  
Blue Reaction

The construction and evaluation of a fully automated Flow Injection-Stopped Flow (FI-SF) spectrophotometric analyser is described. A microcomputer (Rockwell AIM 65) is used to control the analyser (sample injection, stop and start of the pump) through a suitable interface. Data acquisition is achieved using a 12 bit ADC card and a suitable subroutine in 6502 assembly language, allowing data sampling at a frequency of 7.5 kHz. The measurement interface and software were evaluated using a voltage ramp generator. A precision of 0.02-1.1% RSD (N =10) was obtained for voltage ramps in the range of 1-37 mVs-1. The FI-SF analyser was evaluated in routine analysis by developing FI-SF kinetic spectrophotometric methods for the determination of ammonia nitrogen (20-250 ppm, 0.4-2.5% RSD) based on the Berthelot reaction, creatinine (20-220 ppm, 0.9-3.6% RSD) based on the Jaffé reaction, and phosphate (5-30 ppm, 1.0-3.3% RSD) based on the phosphomolybdenum blue reaction. The reaction rate is measured by linear fitting of multiple absorbance readings vs time. Algorithms for automated estimation of the residence time, the linear range of the reaction curve, and data treatment are presented.

Multi-Criteria Analysis in Assessment of the Degree of Degradation Pavement Elements Functional Airports Made of Cement Concrete

2017 ◽  
Author(s):  
Mariusz Wesołowski ◽  
Krzysztof Blacha ◽  
Piotr Barszcz
Keyword(s):  
Quality Management System ◽  
Technical Condition ◽  
Cement Concrete ◽  
Functional Elements ◽  
Surface Degradation ◽  
Visual Method ◽  
Flight Operations ◽  
Multi Criteria Analysis ◽  
Degree Of Degradation

An important factor that affects the safety of flight operations is the proper management of airports, which should be based on the obtained in systematic way information about the state of the surface of the functional elements. One of the characteristic quantities of the technical condition of airport indicator is the assessment of the degree of degradation. It should be noted that the degradation is a slow process extended in time and is the lowering of the properties of the structure by external influences, which in turn generates the changes in their structure. Rating degrade surface should be conducted periodically, which period shall be estimated on the basis of information obtained from the process of the operation of aircraft. Demotions surface is determined on the basis of the type and quantity survey found damage and made repairs. The basis for evaluating the degree of surface degradation is to obtain data from surveys conducted using the method of visual and inventory of them. Research by visual method, despite its apparent simplicity, it is difficult to implement. Qualification of damage or repairs to the appropriate group is often not clear, and therefore the inventory process is described in the documentation of quality management system. The multi-criteria analysis is a method of evaluating the weighted supporting estimating the degree of degradation airfield pavements based on data obtained through inspections performed. Its base is included in the determination of a number of criteria for the selection variant, taking into account different weights to each criterion. The value of the indicator characterizing the degree of surface degradation in relation to estimated criteria allows you to schedule the necessary resources needed to carry out repairs and rational planning of repairs.

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