Name: clean sampling and analysis of river and estuarine waters for trace metal studies
Uploaded: 2016-07-01T13:00:00.000+00:00
Duration: 10 min 44 s
Description: Watch this Scientific Journal Video about Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies at JoVE.com

The authors thank Drs. Bobby J. Presley, Robert Tayloy, Paul Boothe, Mr. Bryan Brattin, and Mr. Mike Metcalf for their assistance during the laborious field sampling and lab work for the practical development and application of "clean techniques".

1. Numune Hazırlama <ol><li> örnekleyici <ol><li> sampler&#39;ın montajı <ol><li> 1.5 m, kimyasal olarak dayanıklı, silikon, pompalama borusunun (OD 0.635 cm) bir 4 m uzunluğunda fluorinatlı etilen propilen (FEP) boru (İD 0.635 cm OD 0.95 cm veya benzeri) takın. </li><li> pompalama tüpüne polipropilen Y-konnektörü yerleştirin ve diğer bir çıkışa ve (20 cm pompalama tüp ile) 0.45 mikron kapsül filtresine 50 cm pompalama tüp bağlayın. </li><li> bir temiz oda (tezgah) &#39;de borulama onlar temizlenir sonra (aşağıya bakınız) birleştirin ve polietilen torba iki kat topluluğu saklayın. </li></ol></li><li> Numune temizleme <ol><li> laboratuvar deterjan çözeltisi ile boru seti (bir peristaltik pompa üzerine 1,5 m pompalama tüpü takarak) doldurun ve 24 saat için bekletin. Daha sonra,% 10 (h / h) HCI ile (reaktif derecesi) ile doldurun ve 48 saat boyunca bekletin, de-iyonize su ile ayarlanmış boru yıkayın. </li><li> İyice W deiyonize ayarlanmış boru temizlemebirkaç kez bırakmayın, ve plastik torbalar içinde topluluğu saklayın. 24 saat boyunca bir% 50 (hac / hac) HNO 3 ile (reaktif derecesi) çözeltisi ıslatarak Y-bağlayıcıları ve kısa pompalama temiz tüplere. </li></ol></li><li> kapsül filtreleri <ol><li> Önce de-iyonize su ile 48 saatlik ıslatma adımı için, daha sonra,% 10 (h / h) HCI çözeltisi bunları yıkayarak kapsül filtreler temizleyin. </li><li> Asit Batırılıp ıslatılmadan sonra, de-iyonize su ile filtre yıkayın ve asidi nötralize etmek için, her filtrenin içine% 21 (ağırlık) NH4OH (alt haşlanmış) çözeltisi 1 ml. </li><li> polietilen fermuarlı çanta giriş ve çıkış, ve mağaza bağlayan 30 cm temizlenmiş pompalama tüpün bir döngü ile bireysel filtre mühür. </li></ol></li></ol></li><li> numune kapları <ol><li> Polietilen (PE, 1000 mi) ve FEP (500 mi, 1.000 mi) iz metal tespiti için konteynerler için şişe kullanın. <ol><li> % 50 daha sonra, deterjan (% 1) ilk (h / h) HNO 3 ıslatarak şişe temizleme(Reaktif derecesi) ve 24, 48 ve 24 saat süre ile,% 10 (h / h) HCI ile (reaktif derecesi) çözeltiler, sırasıyla iki ıslatma kademe arasındaki de-iyonize su ile şişe yıkayın. </li><li> son HCI iliklerine sonra, iyice de-iyonize su (DIW) ile şişe durulayın ve bir temiz oda veya sınıf-100 temiz tezgah (mühürlü kapaklı) şişe kurulayın. </li><li> polietilen fermuarlı çanta ve taşıma için polietilen torbalarda çift torba onları mühür temizlenmiş şişe. </li></ol></li><li> çözünmüş organik karbon (DOC) tayini için temiz bir cam şişeler <ol><li> 48 saat süre ile,% 10 HCl, çözünmüş organik karbon (DOC) analizi için, kehribar borosilikat cam şişe (40 mi) bekletin. de-iyonize su ile temizlenmiş cam şişe durulayın ve kullanımdan önce 2 saat boyunca 480 ° C &#39;de bunları yanma. taşıma için fermuarlı polietilen torbalarda ayrı ayrı şişeleri Seal. </li></ol></li></ol></li></ol> 2. Örnekleme <ol><li> Su numunesi toplama <ol><li> Upon örnekleme yerinde varış, dış torba üzerinde işareti örnek kimlik numarası ve orijinal torbalarda şişeleri tutun. </li><li> Nehir kıyısında ya da bir teknede anda, bir kişi örnekleyici ile çantayı açıp (temizlenmiş) 3 m polipropilen direğine 4-m FEP tüp takmak gerekir. mümkün olduğunca bankadan kutup uzatın ve yaklaşık 30 cm, pompa açılmadan önce nehir akan su yüzeyinin altında FEP boru girişi tutun. </li><li> başka bir kişinin bir peristaltik pompa (dahili pil ile örnekleme pompası) pompa kafasına pompalama tüp takmak zorunda. Pompayı başlatın ve su (aşağı tarafı) toplam numune hacmi en az 3 kez boşaltın. pudrasız eldiven giyin ve örnek şişeleri doldurarak başlatmak için şişe ve kapaklar çanta açın. <ol><li> Başka bir kişinin mevcut Alternatif olarak, eğer üçüncü şahıs iç çanta ve örnek kapaklar açılarak ve b içine örnek boşaltır örnekleme tüpünü tutan sorumlu olmak varottle. </li></ol></li><li> alanına iletkenlik, sıcaklık ve pH ölçümleri için 125 ml&#39;lik bir plastik şişe içinde bir süzülmemiş numune toplayın. </li><li> (1 (bir filtre olmadan çıkış ağzından) İlk (500 ml veya parçacık numune toplanması için 1000 ml) filtresiz örnekleri toplamak ve daha sonra bir filtrelenmiş su numunesi toplamak için kapsül filtre üzerinden gitmek için su zorlamak için plastik bir kelepçe ile çıkışı kapatın L) çözünmüş iz metal tayini için. </li><li> süzüldü örnekleri toplamak DOC ve EDTA ölçümleri için 40 ml amber cam şişeler içinde (filtre ile çıkıştan). </li><li> 1000 ml / dk, yaklaşık 500 ml / dk bir akış oranında su numuneleri toplamak. basıncı (filtreleri &#39;özelliklerine göre) kurmak için başladığında kapsül filtrelerini değiştirin. örneğin her türü için, kalite kontrol alikotları olarak hizmet etmek üzere seçilen konumlarda ilave örnekleri, aynı zamanda alan boşluklar, toplar. </li><li> kuru buz ve depolanan i 40 ml cam şişe yerleştirinbir buz göğüs ve buz sandıklarda polietilen şişeler n. </li></ol></li><li> asılı partikül madde Koleksiyon (SPM) <ol><li> plastik bir süzme hunisi ve kap kullanılarak, vakumla süzülerek 0.4 um polikarbonat (PC), membran filtreler üzerinde SPM (asit yıkandı ve önceden tartılmış) toplayın. </li><li> SPM konsantrasyonlar elde ve partikül iz metal tayini için parçacık örnekleri sağlamak için laboratuvarda kuru membran filtreleri dondurun. </li></ol></li></ol> 3. Numune Tedavi öncesi (İz Metaller Çözünmüş) <ol><li> Çözündürüldü eser metal belirlenmesi için, numune şişelerine 2 ml konsantre edilmiş alt kaynatılmış HNO 3 (1-L numune başına) ilave edilir. FEP şişe içine aktarın çözündürüldü eser metal örnekleri (asidifiye). Alternatif olarak, numuneler FEP şişeler doğrudan toplanabilir. 24 saat (8 ila 15 watt UV lambaları) için FEP şişelerde örnekleri UV-ışın tedavisi. </li></ol> Eser Metal Analizi 4. Önderiştirme ve Tedaviler <ol><li&gt; Önderiştirme reçine <ol><li> Küçük (10-30 mi kapasite) plastik bir kap içine katyon değiştirme reçinesi 2 g tartılır ve bir kap içine 2N HNO 3 solüsyonu az miktarda ilave edin. 10 ml kapasiteli kromatografi kolonu içine reçine dökün. 5 ml 2 N HNO 3 ile yıkanması reçineyi temizleme iki kez (-alt kaynatılmış) ve yüksek saflıkta su (HPW) ile 3 kez yıkayın. </li><li> NH 4 + -formu için reçine dönüştürmek için sütuna (alt haşlanmış) 1 M NH 4 OH 10 ml ekleyin. </li></ol></li><li> Tampon çözeltisi (1 M amonyum asetat) <ol><li> HPW yaklaşık 800 ml (alt kaynatılmış) buzlu asetik asit 57 ml ilave edilir. Amonyum hidroksit ~ 60 ml ilave edilir (% 21, haşlanmış-alt) ve asetik asit ile karıştırılır. 5.5 Nihai pH ve 1000 ml son ses seviyesini ayarlayın. </li></ol></li><li> Zenginleştirme işlemi (tortu metaller çözündürüldü) <ol><li> 30 ml 1 M amonyum Acet eklenerek 5.5 ± 0.3 olana kadar asitleştirildi, UV radyasyona tabi numunelerin pH ayarlamatampon çözelti ve bazı (~ 2.8 mi) NH 4 OH yedik örneklerin içine (alt haşlanmış). </li><li> ~ 30 katyonik değişim reçinesi (Bölüm 4.1) ile dolu sütunun üstünde cm ve ~ 60 cm FEP tüp ve kromatografi kap ve konnektör (dişi Luer) numune şişesi ve önderiştirme sütun bağlamak numune şişesi yerleştirin. </li><li> sütun üzerinde bağlı bir 2-yollu valf kullanılarak 3-5 ml / dak akış hızı, kontrol eder. Numuneler zenginleştirme sütunlar geçmesine izin verin. Numuneler sütunu geçtikten sonra, sütun tüpleri ve kapaklarını çıkarın. </li><li> 2 x 5 mi HPW 1 M amonyum asetat (pH 5.5) 4 x 5 ml ve diğer eser metaller Katyon ayırmak için HPW 2 x 5-ml sütunu tedavi edin. </li><li> Sadece sütunun altında 30 ml asitle yıkanmış PE şişe yerleştirin ve 7 x 1 ml 2 N HNO 3 ile sütun yıkayın PE şişe içine (alt haşlanmış). </li><li> Ağırlık a alarak 2 N HNO 3 atık (~ 8.0 ml) hacmi belirlemeknd 2 N HNO 3 atık özgül ağırlığı. </li></ol></li><li> asılı partikül madde sindirimi <ol><li> SPM örnekleri ile kuru PC filtreleri Freeze ve kuruduktan sonra onları tartın. Talep SPM örnekleri, önceden tartılmış perfloroalkoksi alkan Filtrelerin ile (PFA) damarlar (60 mi kapasite) ve damar içine konsantre HNO 3 3 ml ekleyin. </li><li> 2.5 kg-metre arasında bir sabit tork gemilere Sıkma ve 12 saat boyunca 130 ° C &#39;de, geleneksel bir fırın içinde dijeste edilmiştir. Soğuduktan sonra, gemileri açıp damarlarına HF 2 ml ekleyin. </li><li> 2.5 kg-metre arasında bir sabit tork gemilere Sıkma ve 12 saat boyunca 130 ° C &#39;de, geleneksel bir fırın içinde dijeste edilmiştir. Soğutulduktan sonra, damarlar açıp damarlarına% 4.5 borik asit çözeltisinin 16 mi ekleyin. </li><li> 2.5 kg-metre arasında bir sabit tork gemilere Sıkma ve 12 saat boyunca 130 ° C &#39;de, geleneksel bir fırında sindirimi. Her bir kap tartılır ve her özeti çözeltisinin özgül ağırlığını belirlerNihai sindirmek hacim elde edilir. </li><li> (Nihai filtre üzerinde numune ağırlığı bölü hacim özet), her bir filtre üzerinde SPM nihai hacim ve ağırlığından sindirimi için seyreltme faktörünü hesaplar. </li></ol></li></ol> 5. Numune Analizi <ol><li> iz metaller <ol><li> Önceden konsantre edilmiş numune ve alev atomik absorpsiyon spektrofotometresi, grafit fırın atomik absorpsiyon spektrofotometresi kullanılarak parçacıklardan çözeltisi çözündürüldü, ve / veya indüktif olarak bağlanmış plazma içindeki iz metalleri (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) konsantrasyonlarını belirlemek kütle spektrometresi. </li><li> indüktif eşleşmiş plazma-atomik emisyon spektrometresi ile zenginleştirme önce çizilmiş alt örnekleri ve asılı partiküler madde digests, büyük iyonlar konsantrasyonları ve bazı iz metaller, belirleyin. </li></ol></li><li> yardımcı parametreler <ol><li> taşınabilir cihazlar kullanarak, alanında örnek sıcaklık, pH, tuzluluk ve iletkenlik belirleyin. </li><li> Belirleme çözülmüş ya daKızılötesi spektrometresi 21 karbondioksit tespiti ile ıslak oksidasyon dayalı Ganiç karbon (DOC) Bir Toplam Organik Karbon Analiz tarafından konsantrasyonları. Yerleşik prosedürlere 22,23, aşağıdaki (a SPD-M10AV Diodearray dedektörü ile), yüksek performanslı sıvı kromatografisiyle toplam EDTA konsantrasyonunun belirlenmesi. </li></ol></li></ol>

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The authors have no conflict of interests to disclose.

doğal sularda güvenilir eser metal veri elde kirlenmeyi azaltmak amacı numune toplama, işleme, pretreatments ve analiz sırasında vurguladığı gibi büyük dikkat gerektirir. konsantrasyonları önceden bildirilen daha düşük büyüklükte emir olabilir bulundu son yirmi yılda &quot;temiz teknikleri&quot; kullanılarak elde edilen doğal sularda metal konsantrasyonları izleyin. eser metal düzeyleri doğru insanlar ve daha yüksek organizmalara zararlı etkilerinin daha iyi değerlendirilmesi sonucunda ölç?...

Yaygın doğal sular için elde edilen bazı eser metal sonuçları numune toplama, tedavi ve kararlılık 1,2 sırasında uygulanan yetersiz tekniklerden kaynaklanan eserler nedeniyle hatalı olabileceği kabul edilmiştir. Çözünmüş eser metallerin (yüzey sularında 3 nM aralığında alt nM) gerçek konsantrasyonları daha önce yayınlanan değerlerden daha düşük büyüklükte şimdi iki kararlarıdır. Aynı durum okyanus sularında kabul çözünmüş eser metal konsantrasyonları son 40 yılda büyüklüğe göre azalmıştır ya da öylesine gelişmiş örnekleme ve analitik yöntemler getirilmiştir gibi deniz kimyada bulunmuştur. Çabaları eser metal analizleri 4-8 tüm aşamalarında azaltılması veya iz metal kirlenmesi kaldırılmasına yönelik &quot;temiz teknikleri&quot; nin gelişmelere veri kalitesini artırmak için yapılmıştır. ortam sıcaklığında eser metal konsantrasyonlarının belirlenmesi içinseviyeleri, zenginleştirme sıklıkla gerekmektedir. İyon değiş tokuş teknikleri 8-12 yaygın verimli zenginleştirilmesi için uygulanmıştır. Kirlenme kapların duvarları ortaya çıkabilir, konteyner, sampler, numune işleme ve depolama, ve örnek korunması ve analiz 7,13 temizliği. Daha yakın zamanda gerçekleştirilen temiz yöntemlerle tüm çalışmalar, doğal sularda eser metal konsantrasyonları tipik olarak iyi rutin yöntemlerle 7 algılama sınırlarının altında olduğunu göstermektedir. 1990&#39;ların başında şüpheli eser metal verilerinin tanınması yana, temiz yöntemler iz metal tayini 14 ABD EPA (Çevre Koruma Ajansı) Rehberin içine dahil edilmiştir ve US Geological Survey 15 projeleri onların su kalitesinin izlenmesi için temiz yöntemler benimsemiştir. eser metal çalışmaları için temiz yöntemler sağlam ve doğru veri tabanı oluşturmak amacıyla tüm projelerde istihdam edilmek üzere gerekir. <pPrensip olarak class = &quot;jove_content&quot;&gt;, iz metal tayini için kullanılan su numuneleri belirli bir malzeme ve kompozisyon, enstrümantal analiz başlamadan önce, düzgün, uygun kaplar ve aparat kullanarak saklanan ve tedavi uygun örnekleme dişli alınmalıdır. asılı partikül madde (SPM) numune depolama süresi boyunca değişiklikler yapılabilir ve su bileşimi, su örneklerinden SPM hızlı ayırma değiştirebilir yana su ortamlarında eser metal çalışmaları için yaygın bir uygulamadır. doğal sularda çözündürüldü eser metal konsantrasyonlarının belirlenmesi için, süzme gereklidir ve satır filtreleme teknikleri, uygun ve etkili. Dağıtım ve yüzey ve yeraltı suları gibi sucul ortamlarda eser metallerin davranışı doğal (örneğin, hava) ve antropojenik etkilenebilir (örn atıksu atıklar) bu tür yeniden gibi faktörler, yanı sıra diğer çevre koşulları,Bölgesel jeoloji, morfoloji, arazi kullanımı ve bitki örtüsü, iklim 16-19. Bundan sonra, bu asılı partikül madde konsantrasyonları (SPM), çözünmüş organik karbon (DOC), insan kaynaklı ligand (örneğin, etilendiamintetraasetik asit, EDTA), bir tuzu, redoks potansiyeli ve pH 17-20 olarak fiziksel parametreleri farklılıklara neden olabilir. Bu nedenle, doğru ve alakalı eser metal çalışmaları uygun eser metal analizi için numune toplama yanı sıra ilgili faktörler ve parametrelerin belirlenmesini gerektirmektedir.

<table><tbody><tr><td>Nitric Acid</td><td>Seastar Chemicals</td><td></td><td>Baseline grade</td></tr><tr><td>Ammonium hydroxide</td><td>Seastar Chemicals</td><td></td><td>Baseline grade</td></tr><tr><td>Acetic Acid</td><td>Seastar Chemicals</td><td></td><td>Baseline grade</td></tr><tr><td>Nitric Acid</td><td>J. T. Baker</td><td>9601-05</td><td>Reagent grade</td></tr><tr><td>Hydrochloric acid</td><td>J. T. Baker</td><td>9530-33</td><td>Reagent grade</td></tr><tr><td>Chromatographic columns</td><td>Bio-Rad</td><td>7311550&amp;nbsp;</td><td>Poly-Prep</td></tr><tr><td>Column stack caps</td><td>Bio-Rad</td><td>7311555</td><td></td></tr><tr><td>Cap connectors (female Luers)</td><td>Bio-Rad</td><td>7318223</td><td></td></tr><tr><td>2-way stopcocks</td><td>Bio-Rad</td><td>7328102</td><td></td></tr><tr><td>Cation exchange resin</td><td>Bio-Rad</td><td>1422832&amp;nbsp;</td><td>Chelex-100</td></tr><tr><td>Portable sampler (sampling pump)</td><td>Cole Palmer</td><td>EW-07571-00</td><td></td></tr><tr><td>FEP tube</td><td>Cole Palmer</td><td>EW-06450-07</td><td>6.4 mm I.D., 9.5 mm O.D.</td></tr><tr><td>Pumping tube</td><td>Cole Palmer</td><td>EW-06424-24</td><td>6.4 mm I.D. C-Flex</td></tr><tr><td>Capsule filter (0.4 mm)</td><td>Fisher Scientific</td><td>WP4HY410F0</td><td>polypropylene casing</td></tr><tr><td>1 L low density polyethylene bottle</td><td>NALGE NUNC INTERNATIONAL</td><td>312088-0032</td><td></td></tr><tr><td>1 L (or 500 ml) FEP bottle</td><td>NALGE NUNC INTERNATIONAL</td><td>381600-0032</td><td></td></tr></tbody></table>

clean sampling and analysis of river and estuarine waters for trace metal studies

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination control. Developments of some techniques aiming to reduce trace metal contamination in the last couple of decades have resulted in concentrations reported now being orders of magnitude lower than those in the past. These low concentrations often necessitate preconcentration of water samples prior to instrumental analysis of samples. Since contamination can appear in all phases of trace metal analyses, including sample collection (and during preparation of sampling containers), storage and handling, pretreatments, and instrumental analysis, specific care needs to be taken in order to reduce contamination levels at all steps. The effort to develop and utilize "clean techniques" in trace metal studies allows scientists to investigate trace metal distributions and chemical and biological behavior in greater details. This advancement also provides the required accuracy and precision of trace metal data allowing for environmental conditions to be related to trace metal concentrations in aquatic environments.
This protocol that is presented here details needed materials for sample preparation, sample collection, sample pretreatment including preconcentration, and instrumental analysis. By reducing contamination throughout all phases mentioned above for trace metal analysis, much lower detection limits and thus accuracy can be achieved. The effectiveness of "clean techniques" is further demonstrated using low field blanks and good recoveries for standard reference material. The data quality that can be obtained thus enables the assessment of trace metal distributions and their relationships to environmental parameters.

gelişme &quot;temiz teknikler&quot; kullanımı ile, şimdi, ortam sularında doğru eser metal konsantrasyonları elde etmek için, suların örneklerde eser metallerin zenginleştirme yaygın bir uygulama olduğu kabul edilmektedir. doğal sularda eser metallerin en su kalitesi kriterleri düşük mikrogram / L aralığında iken, alt saptama limitleri sucul ortamlarda ortam konsantrasyonlarda iz metaller üzerinde jeokimyasal ve biyolojik etkilerini araştırmak için ihtiyaç vardı...

Watch this Scientific Journal Video about Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies at JoVE.com

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Special care using "clean techniques" is required to properly collect and process water samples for trace metal studies in aquatic environments. A protocol for sampling, processing, and analytical procedures with the aim of obtaining reliable environmental monitoring data and results with high sensitivity for detailed trace metal studies is presented.

Temiz Örnekleme ve Eser Metal Çalışmaları Nehri ve haliç Waters Analizi

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination ...

clean-sampling-analysis-river-estuarine-waters-for-trace-metal

Research

JoVE Journal

Environment

11.4K Görüntüleme.  National Sun Yat-sen University. Special care using "clean techniques" is required to properly collect and process water samples for trace metal studies in aquatic environments. A protocol for sampling, processing, and analytical procedures with the aim of obtaining reliable environmental monitoring data and results with high sensitivity for detailed trace metal studies is presented.

Video: Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

Increasing demand for renewable fuels has researchers investigating the feasibility of alternative feedstocks, such as microalgae. Inherent advantages include high potential yield, use of non-arable land and integration with waste streams. The nutrient requirements of a large-scale microalgae production system will require the coupling of cultivation systems with industrial waste resources, such as carbon dioxide from flue gas and nutrients from wastewater. Inorganic contaminants present in these wastes can potentially lead to bioaccumulation in microalgal biomass negatively impact productivity and limiting end use. This study focuses on the experimental evaluation of the impact and the fate of 14 inorganic contaminants (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Se, Sn, V and Zn) on Nannochloropsis salina growth. Microalgae were cultivated in photobioreactors illuminated at 984 &#181;mol m-2 sec-1 and maintained at pH 7 in a growth media polluted with inorganic contaminants at levels expected based on the composition found in commercial coal flue gas systems. Contaminants present in the biomass and the medium at the end of a 7 day growth period were analytically quantified through cold vapor atomic absorption spectrometry for Hg and through inductively coupled plasma mass spectrometry for As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Sn, V and Zn. Results show N. salina is a sensitive strain to the multi-metal environment with a statistical decrease in biomass yieldwith the introduction of these contaminants. The techniques presented here are adequate for quantifying algal growth and determining the fate of inorganic contaminants.

Integration of microalgal cultivation with industrial flue gas will ultimately introduce heavy metals and other inorganic compounds into the growth media. This study presents a procedure used to determine the end fate and impact of heavy metals and inorganic contaminants on the growth of Nannochloropsis salina grown in photobioreactors.

Ağır Metal ve Mikroalglerden Verimlilik Diğer İnorganik Bulaşanlar Kantitasyonu

Increasing demand for renewable fuels has researchers investigating the feasibility of alternative feedstocks, such as microalgae. Inherent advantages ...

Çevre

Sediment Core Sectioning and Extraction of Pore Waters under Anoxic Conditions

We demonstrate a method for sectioning sediment cores and extracting pore waters while maintaining oxygen-free conditions. A simple, inexpensive system is built and can be transported to a temporary work space close to field sampling site(s) to facilitate rapid analysis. Cores are extruded into a portable glove bag, where they are sectioned and each 1-3 cm thick section (depending on core diameter) is sealed into 50 ml centrifuge tubes. Pore waters are separated with centrifugation outside of the glove bag and then returned to the glove bag for separation from the sediment. These extracted pore water samples can be analyzed immediately. Immediate analyses of redox sensitive species, such as sulfide, iron speciation, and arsenic speciation indicate that oxidation of pore waters is minimal; some samples show approximately 100% of the reduced species, e.g. 100% Fe(II) with no detectable Fe(III). Both sediment and pore water samples can be preserved to maintain chemical species for further analysis upon return to the laboratory.

A protocol for sectioning sediment cores and extracting pore waters under anoxic conditions in order to permit analysis of redox sensitive species in both solids and fluids is presented.

Anoksik Koşullarında Tortu Çekirdek Kesit ve Gözenek Waters Ekstraksiyon

We demonstrate a method for sectioning sediment cores and extracting pore waters while maintaining oxygen-free conditions. A simple, inexpensive system is ...

Watershed Planning within a Quantitative Scenario Analysis Framework

There is a critical need for tools and methodologies capable of managing aquatic systems within heavily impacted watersheds. Current efforts often fall short as a result of an inability to quantify and predict complex cumulative effects of current and future land use scenarios at relevant spatial scales. The goal of this manuscript is to provide methods for conducting a targeted watershed assessment that enables resource managers to produce landscape-based cumulative effects models for use within a scenario analysis management framework. Sites are first selected for inclusion within the watershed assessment by identifying sites that fall along independent gradients and combinations of known stressors. Field and laboratory techniques are then used to obtain data on the physical, chemical, and biological effects of multiple land use activities. Multiple linear regression analysis is then used to produce landscape-based cumulative effects models for predicting aquatic conditions. Lastly, methods for incorporating cumulative effects models within a scenario analysis framework for guiding management and regulatory decisions (e.g., permitting and mitigation) within actively developing watersheds are discussed and demonstrated for 2 sub-watersheds within the mountaintop mining region of central Appalachia. The watershed assessment and management approach provided herein enables resource managers to facilitate economic and development activity while protecting aquatic resources and producing opportunity for net ecological benefits through targeted remediation.

There is a critical need for tools and methodologies capable of managing aquatic systems in the face of uncertain future conditions. We provide methods for conducting a targeted watershed assessment that enables resource managers to produce landscape-based cumulative effects models for use within a scenario analysis management framework.

Bir Kantitatif Senaryo Analizi Çerçevesinde Planlama Havza

There is a critical need for tools and methodologies capable of managing aquatic systems within heavily impacted watersheds. Current efforts often fall ...

Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in water resources is a prerequisite for understanding the drivers of the pollutant loads and for making informed water resource management decisions. The commonly used &#34;grab sampling&#34; method provides the concentrations of pollutants at the time of sampling (i.e., a snapshot concentration) and may under- or overpredict the pollutant concentrations and loads. Continuous monitoring of nutrients and sediment has recently received more attention due to advances in computing, sensing technology, and storage devices. This protocol demonstrates the use of sensors, sondes, and instrumentation to continuously monitor in situ nitrate, ammonium, turbidity, pH, conductivity, temperature, and dissolved oxygen (DO) and to calculate the loads from two streams (ditches) in two agricultural watersheds. With the proper calibration, maintenance, and operation of sensors and sondes, good water quality data can be obtained by overcoming challenging conditions such as fouling and debris buildup. The method can also be used in watersheds of various sizes and characterized by agricultural, forested, and/or urban land.

With the advancement of technology and the rise in end-user expectations, the need and use of higher temporal resolution data for pollutant load estimation has increased. This protocol describes a method for continuous in situ water quality monitoring to obtain higher temporal resolution data for informed water resource management decisions.

Besin ve tortu tarım havza içinde sürekli Instream izleme

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in ...

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those of suspended/sinking particles. Here, we present an all plastic (Polypropylene and Polycarbonate), multi-layer filtration system for collection of suspended particulate matter (SPM) at sea. This ultra-clean sampling device has been designed and developed specifically for trace element studies. Meticulous selection of all non-metallic materials and utilization of an in-line flow-through procedure minimizes any possible metal contamination during sampling. This system has been successfully tested and tweaked for determining trace metals (e.g., Fe, Al, Mn, Cd, Cu, Ni) on particles of varying size in coastal and open ocean waters. Results from the South China Sea at the South East Asia Time-Series (SEATS) station indicate that diurnal variations and spatial distribution of plankton in the euphotic zone can be easily resolved and recognized. Chemical analysis of size-fractionated particles in surface waters of the Taiwan Strait suggests that the larger particles (&#62;153 &#181;m) were mostly biologically derived, while the smaller particles (10 - 63 &#181;m) were mostly composed of inorganic matter. Apart from Cd, the concentrations of metals (Fe, Al, Mn, Cu, Ni) decreased with increasing size.

Plankton and suspended particles play a major role in the biogeochemical cycles in the ocean. Here, we provide an ultra-clean, low stress method for the collection of various sizes of particles and plankton at sea with the capability of handling large volumes of seawater.

Şeker boyutu deniz Plankton ve askıya alınan parçacıkları toplamak için Ultra temiz bir çok katmanlı aparat

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those ...

Seawater Sampling and Collection

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses. For today's demonstration samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. An A-frame derrick, with a multi-purpose winch and cable system, is used in combination with Niskin or Go-Flo water sampling bottles. Conductivity, Temperature, and Depth (CTD) sensors are also used to sample the underlying water mass. To minimize outgassing, trace gas samples are collected first.  Then, nutrients, water chemistry, and cell counts are determined. Finally, waters are collected for biomass filtration. The set-up and collection time for a single cast is ~1.5 hours at a maximum depth of 215 meters. Therefore, a total of 6 hours is generally needed to complete the collection series described here.

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses.

Deniz suyu Örnekleme ve Tahsilat

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass ...

Biyoloji

Two-Dimensional Visualization and Quantification of Labile, Inorganic Plant Nutrients and Contaminants in Soil

We describe a method for two-dimensional (2D) visualization and quantification of the distribution of labile (i.e., reversibly adsorbed) inorganic nutrient (e.g., P, Fe, Mn) and contaminant (e.g., As, Cd, Pb) solute species in the soil adjacent to plant roots (the &#8216;rhizosphere&#8217;) at sub-millimeter (~100 &#181;m) spatial resolution. The method combines sink-based solute sampling by the diffusive gradients in thin films (DGT) technique with spatially resolved chemical analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The DGT technique is based on thin hydrogels with homogeneously distributed analyte-selective binding phases. The variety of available binding phases allows for the preparation of different DGT gel types following simple gel fabrication procedures. For DGT gel deployment in the rhizosphere, plants are grown in flat, transparent growth containers (rhizotrons), which enable minimal invasive access to a soil-grown root system. After a pre-growth period, DGT gels are applied to selected regions of interest for in situ solute sampling in the rhizosphere. Afterwards, DGT gels are retrieved and prepared for subsequent chemical analysis of the bound solutes using LA-ICP-MS line-scan imaging. Application of internal normalization using 13C and external calibration using matrix-matched gel standards further allows for the quantification of the 2D solute fluxes. This method is unique in its capability to generate quantitative, sub-mm scale 2D images of multi-element solute fluxes in soil-plant environments, exceeding the achievable spatial resolution of other methods for measuring solute gradients in the rhizosphere substantially. We present the application and evaluation of the method for imaging multiple cationic and anionic solute species in the rhizosphere of terrestrial plants and highlight the possibility of combining this method with complementary solute imaging techniques.

This protocol presents a workflow for sub-mm 2D visualization of multiple labile inorganic nutrient and contaminant solute species using diffusive gradients in thin films (DGT) combined with mass spectrometry imaging. Solute sampling and high-resolution chemical analysis are described in detail for quantitative mapping of solutes in the rhizosphere of terrestrial plants.

Topraktaki Labile, Inorganik Bitki Besinleri ve Kirleticilerin İki Boyutlu Görselleştirilmesi ve Nicelleştirilmesi

We describe a method for two-dimensional (2D) visualization and quantification of the distribution of labile (i.e., reversibly adsorbed) inorganic ...

Dissolved Solute Sampling Across an Oxic-Anoxic Soil-Water Interface Using Microdialysis Profilers

Biogeochemical processes shift rapidly in both spatial (millimeter scale) and temporal (hour scale to day scale) dimensions at the oxic-anoxic interface in response to disturbances. Deciphering the rapid biogeochemical changes requires in situ, minimally invasive tools with high spatial and temporal sampling resolution. However, the available passive sampling devices are not very useful in many cases either due to their disposable nature or the complexity and extensive workload for sample preparation.
To address this problem, a microdialysis profiler with 33 individual polyethersulfone nanomembrane tubes (semipermeable, &#60;20 nm pore size) integrated into the one-dimensional skeleton (60 mm) was established to iteratively sample the dissolved compounds in porewater across the soil-water interface at a high resolution of 1.8 mm (outer diameter plus one spacing, i.e., 0.1 mm between probes). The sampling mechanism is based on the principle of concentration gradient diffusion. The automatic loading of degassed water allows minimal disturbance to the chemical species across the oxic-anoxic interface.
This paper describes the procedures of device setup and continuous porewater sampling across the soil-water interface on a daily basis. Concentration-depth profiles were selectively measured before (on Day 6) and after (on Day 7) disturbances induced by irrigation. The results showed that concentration-depth profiles were undergoing rapid changes, especially for redox-sensitive elements (i.e., iron and arsenic). These protocols can help investigate the biogeochemical responses across the soil-water interface under various disturbances caused by physical, chemical, and biological factors. The paper thoroughly discusses the advantages and disadvantages of this method for potential use in the environmental sciences.

A microdialysis profiler is described to sample dissolved porewater solutes across an oxic-anoxic soil-water interface in situ with minimal disturbance. This device is designed to capture rapid changes in concentration-depth profiles induced by disturbances at the soil-water interface and beyond.

Mikrodiyaliz profilleyicileri kullanılarak oksik-anoksik toprak-su arayüzü boyunca çözünmüş çözünmüş numune alımı

Biogeochemical processes shift rapidly in both spatial (millimeter scale) and temporal (hour scale to day scale) dimensions at the oxic-anoxic interface ...

Hellgrammite as a Non-Conventional Biomonitor for Surface Water and Environmental Health Assessment

The larvae of dobsonflies from the genus Corydalus, commonly known as Hellgrammites, are characterized by their notable size, extensive range of occurrence, and extended period of immaturity, which can last up to one year. Hellgrammites are clearly known to exhibit sensitivity to pollution and habitat structure impacts. Given these unique features, using Corydalus texanus larvae is highly suitable as reliable biomonitoring agents to assess the ecological integrity of aquatic ecosystems. This protocol aims to provide the necessary tools for C. texanus assessment and demonstrate their efficacy through a case study. Research findings have practical implications, indicating that C. texanus larvae exhibit early-warning responses to mining pollution, bioaccumulating high amounts of heavy metals such as Zn, Fe, and Al. The presence or absence of C. texanus populations may serve as a helpful indicator for identifying potential issues related to ecosystem health. The unconventional approach has shown early warnings of pollution in mining-impacted sites, highlighting the need for timely action to protect the environment. Given their unique traits, the use of C. texanus larvae is highly suggested as a reliable non-conventional bioindicator.

This protocol describes the use of biomarkers for the early detection of deleterious impacts in aquatic ecosystems. The biomarkers are closely related to sentinel traits, and their changes aid in detecting early-warning damages.

The larvae of dobsonflies from the genus Corydalus, commonly known as Hellgrammites, are characterized by their notable size, extensive range of ...

Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples

This paper describes a fabrication protocol for a dipole-assisted solid phase extraction (SPE) microchip available for trace metal analysis in water samples. A brief overview of the evolution of chip-based SPE techniques is provided. This is followed by an introduction to specific polymeric materials and their role in SPE. To develop an innovative dipole-assisted SPE technique, a chlorine (Cl)-containing SPE functionality was implanted into a poly(methyl methacrylate) (PMMA) microchip. Herein, diverse analytical techniques including contact angle analysis, Raman spectroscopic analysis, and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis were employed to validate the utility of the implantation protocol of the C-Cl moieties on the PMMA. The analytical results of the X-ray absorption near-edge structure (XANES) analysis also demonstrated the feasibility of the Cl-containing PMMA used as an extraction medium by virtue of the dipole-ion interactions between the highly electronegative C-Cl moieties and the positively charged metal ions.

The fabrication protocol of a dipole-assisted solid phase extraction microchip for the trace metal analysis is presented.

Su Örneklerinde Eser Metal Analizi için Dipol destekli Katı Faz Ekstraksiyon Microchip Fabrikasyon

This paper describes a fabrication protocol for a dipole-assisted solid phase extraction (SPE) microchip available for trace metal analysis in water ...