Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userLidar Techniques and Applications in Detection of some Gaseous Pollutants (Review)
الليدار و استخداماته في الكشف عن بعض الملوثات الغازية (دراسة مرجعية)
2479
5 57
0
(
0
)
Authors
عصام فواز الجغامي( باحث )
Created by
Shamra Editor
Ask ChatGPT about the research
تهدف هذه الدراسة المرجعية إلى التعريف بتقانة الليدار و تطبيقاتها في استشعار مركبـات الغـلاف الجوي عن بعد. و تبين كيف يساعد الليدار في رسم خرائط ثلاثية البعد، لتوزع الملوثات، تمتد إلى مسافة عدة كيلومترات. أما حدود الكشف عن الملوثات فتبلغ قيماً من مرتبة ppb ، مما يعطـي طريقـة الليـدار تفوقها، من ناحية الدقة و الحساسية، على جميع طرائق الكشف الكيميائيـة و الفيزيائيـة علـى اخـتلاف أنواعها. يتعرض هذا العمل لدراسة الملوثات NO , NO2 , SO2 , O3 , HCl , C2H4 و البنـزن، و التولـوين، إضافة إلى الزئبق الذري. كما يبين أطوال أمواج الامتصاص، و المقاطع الفعالة التفاضلية لهذه الملوثات. و يتعرض إلى جانب ذلك إلى معالجة المتطلبات التقانية و التصاميم المختلفة لليدار. من ناحية أخرى، تعطي هذه الدراسة مواصفات المنابع الليزرية المتعددة المستخدمة في مجموعـات الليدار، مثل ليزر YAG:Nd ، و Dye – ليزر، و غيرها. و كذلك طاقة النبضة و أمـدها الزمنـي و معـدل تكرارها و البلورات اللاخطية المستخدمة لمضاعفة التواتر و الحصول على خطوط ليزريـة فـي مجـالات طيفية مختلفة، مما يسمح بتوسيع مجال عمل الليدار.
This review aims to show the techniques of lidar in atmospheric remote sensing, which can be utilized to draw three-dimensional maps of pollutants distribution over path lengths of the order of few kilometers. The detection limits achieve values of the order of ppb. This sensitivity and accuracy gives this method its superiority over all other physical and chemical methods of detection. Some details of this method are given for the following pollutants: NO, NO2 , SO 2, O3, HCl, C2H4, benzene and toluene, as well as atomic mercury. This work shows, for these pollutants, absorption wavelengths, differential cross sections and detection limits. In addition to dealing with the technical requirements and different designs of Lidar. On the other hand, this review study handles the characteristics of many laser sources used in lidar systems such as, Nd:YAG- laser, Dye- laser and others. Especially it concentrates on pulse energy, time duration, repetition rate and nonlinear crystals, used for frequency doubling, which broaden the working region of the lidar.
References used
Svanberg S. (1992) Atomic and Molecular Spectroscopy: Basic concepts and Practical Applications, 2nd ed., Springer Ser. At. Plasmas, Vol. 6. Springer – Verlag, Heidelberg
Wolf, J. P., Köste, L. (1990) Remote detection of atmospheric pollutants using differential absorption Lidar technique. In Applied Laser Spectroscopy (W. Demtröder and M. Inguscio, Eds.), pp. 435 – 467 . Plenum, New York
Sigrist ed. M.W. (1994). Air Monitoring by Spectroscopic Techniques, John Wiely & Sons, Inc., New York
rate research
Read More
In This study it has been uses a network for monitoring the pollution with organochlorine pesticides in There marine stations at Lattakia coast: Fishing port, AfamiaCoast, High Institute Of Marine Research Coastusing Cages contained species of musse
lswitch are filter feeders Brachidontes varibilis. Samples had been collected from Lattakia coast.
The results showed a great efficiency of the made network for monitoring the organic pollution in marine environment. It has been recorded a concentration of DDTs is accumulated lower than 2ng/g , Endosulfane and HCB is lower than 1 ng/g too. The results showed that the HCH compounds is dominant in all stations.organochlorine pesticides is accumulated mostly in the biota of station Fishing port, Afamia Coast
Alsin Spring is the most important water sources in Syrian coastal area, due to it is the source of drinking water for the main cities and towns in the Syrian coast. This research aimed to study some contaminant indicators in Alsin spring and some t
aps of distribution system of Alsin drinking water, and compare the Indicators with samples of bottled drinking water from Alsin spring and three other water sources (Drekish, Bukkeen, and Alfigeh). The study included determining the concentrations of nitrates, nitrites and some heavy metals including lead, cadmium and nickel in water samples. The results showed that all water sources contain varying concentrations of lead, while the nickel and cadmium were vary in drinking water samples; The concentrations of nickel and cadmium in some samples were low while were under the detection limits in other samples. The analysis of samples of bottled drinking water showed that the samples from Alfigeh spring were the lesser contamination with heavy metals, while the samples from Alsin spring were contain highest concentrations of lead and nickel. The samples of bottled water from Bukkeen spring contain the highest level of cadmium. The results showed that the concentrations of nitrate, nitrite and heavy metals differ depending on the water source. However, all these concentrations were lower and within the acceptable limits of Syrian standard for drinking water. The study concluded that water resources in the coastal area are distinguished with their higher pure.
Meteorological elements affect the dynamics of air pollutants, where
these elements can play an important role in dispersing and
transferring air pollutants as well as to photochemical reactions of
secondary air pollutants.
This study was conduct
ed to analyze the effect of several
meteorological variables on the concentrations of some air pollutants
(Co, NO2, SO2, O3, PM10) at two sites in Damascus city, by using the
Pearson correlation coefficient.
This study has been conducted to identify the levels of heavy
metals (lead, cadmium, nickel, cobalt, copper, iron, manganese, and
zinc) in the following spices: Nutmeg, turmeric, cinnamon, ginger,
cardamom, nigella sativa, black pepper, cumin, coriander, curry,
and mixed spices.
This study was conducted to identify the levels of heavy metals (lead, cadmium, mercury, nickel, copper, iron, zinc) in the following processed local and imported meat: Sardine (canned full), Tuna (canned chunks), Hammour (frozen full), Euphrates Fis
h (frozen full), fish produced at Qattinah Lake in Syria (frozen full) , lamb (frozen ground), beef (frozen ground), lamb sausage (frozen full), beef sausage (frozen full), sausageproduced in Netherlands (frozen stuffed), lamb liver (frozen full), broiler chicken liver (frozen full), broiler chicken (frozen full), chicken mortadella (canned), beef mortadella (canned), chicken mortadella (canned) produced in Netherlands. Heavy metal concentrations were identified in the samples of the studied meat by atomic absorption spectrometer. The concentrations taken in the wet weight measured in (ppm) were as follows: lead values range between (0.1–5.61),cadmium(0.01–2.02), mercury (0.14 –79.01), nickel (0.11 - 0.82), copper (0.24 – 6.89), iron (1.01 - 91.03), zinc (8.14 - 45.5). It was noticed that in some of the studied samples of the imported and locally-processed meat the levels of lead, cadmium, mercury, and nickel were above the levels permitted by WHO (World Health Organization) and by FAO (Food and Agriculture Organization).While the concentrations of copper, iron, and zincwere belowthelevels permitted.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
