Many government agencies and other organizations sample natural alpine and subalpine surface waters using varying protocols for sample storage and filtration. Simplification of protocols would be beneficial if it could be shown that sample quality is unaffected. In this study, samples collected from low ionic strength waters in alpine and subalpine lake inlets and outlets in the western United States were used to evaluate (1) effects of refrigerated storage time on the chemistry of unfiltered samples, and (2) differences in sample filtration protocols. No analytes exhibited significant changes when stored less than 48 h. Six analytes (pH, sodium, ammonium, potassium, chloride, sulfate) exhibited statistically significant (but small) changes when storage time exceeded 48 h. Two analytes (calcium, nitrate) were significantly higher when samples were field filtered than when filtered in the laboratory, but the differences were also small. For waters similar to those in this test, unfiltered refrigerated samples may be stored up to 48 h without compromising sample quality. The small differences between field and lab filtration do not justify the expense, training, and contamination risk of field filtration.
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http://dx.doi.org/10.1007/s10661-006-9460-x | DOI Listing |
J Environ Manage
January 2025
Department of Environmental Sciences, Central University of Himachal Pradesh, Dharamshala, 176215, India.
Microplastics (MPs) are produced from various primary and secondary sources and pose multifaceted environmental problems. They are of non-biodegradable nature and may stay in aquatic environments for a long time period. The present review has covered novel aspects pertaining to MPs that were not covered in earlier studies.
View Article and Find Full Text PDFEnviron Int
January 2025
Department of Environmental Health Sciences, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea; Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea. Electronic address:
This study evaluated the inhalation of mask-derived materials by simulating real breathing conditions and examined how the amount of inhaled materials varies with breathing flow rate and duration. Three types of non-certified reusable masks and two types of certified disposable masks were selected. For each mask, five different hazardous materials were captured and analyzed in three replicates with two breathing flow rates of 30 L/min and 85 L/min and two breathing time combinations of 15 min and 60 min.
View Article and Find Full Text PDFMolecules
January 2025
Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui University, Hefei 230601, China.
Carbon-based nanomaterials with excellent electrical and optical properties are highly sought after for a plethora of hybrid applications, ranging from advanced sustainable energy storage devices to opto-electronic components. In this contribution, we examine in detail the dependence of electrical conductivity and the ultrafast optical nonlinearity of graphene oxide (GO) films on their degrees of reduction, as well as the link between the two properties. The GO films were first synthesized through the vacuum filtration method and then reduced partially and controllably by way of femtosecond laser direct writing with varying power doses.
View Article and Find Full Text PDFMolecules
January 2025
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150025, China.
In this research, we synthesized a series of TiCT nanosheets with varying lateral dimensions and conducted a thorough investigation into the profound relationship between the electrochemical performance of TiCT materials and their lateral sizes. This study innovatively incorporates a clever combination of small-sized and large-sized TiCT nanosheets in the electrode preparation process. This strategy yields excellent results at low scan rates, with the fabricated electrode achieving a high volumetric capacitance of approximately 658 F/g.
View Article and Find Full Text PDFHematology
December 2025
Department of Blood Transfusion, First Affiliated Hospital, Third Military Medical University (Army Medical University), Chongqing, People's Republic of China.
Background: Platelet concentrates play an important role in clinical treatment such as platelet function disorders and thrombocytopenia. In the process of preparation and storage of platelets, centrifugation, leukofiltration, and agitation will cause morphological changes and impaired function of platelets, which is associated with the increase of platelet transfusion refractoriness, and named as platelet storage lesion (PSL).
Method: This paper proposes three major operations (centrifugation, agitation, and leukofiltration) that platelets experience during the preparation and storage process, to explore the effect of physical cues on PSL.
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