Novel shoreline cap for controlling sheen and dissolved‐phase constituent discharge

2020 ◽  
Vol 30 (2) ◽  
pp. 5-14
Author(s):  
Jeff L. Gentry ◽  
Alexandra Salter‐Blanc ◽  
Keith Sheets ◽  
Bhawana Sharma ◽  
Laura Tochko ◽  
...  
1998 ◽  
Vol 38 (2) ◽  
pp. 185-192 ◽  
Author(s):  
M. J. Bauer ◽  
R. Herrmann ◽  
A. Martin ◽  
H. Zellmann

Large amounts of phthalic acid esters (PAEs) are leached from plastics dumped at municipal landfills. This leachate transports PAEs either adsorbed on particulate matter or in dissolved phase. Dissolved organic macromolecules, mainly humic-like substances, enhance the solubility of PAEs. In the biochemical environments of municipal landfills short chain PAEs can be degraded by base-catalyzed hydrolysis or by microorganisms which enzymatically split the side chains. However, there is no cleavage of the aromatic ring. Long chain PAEs like di-(2-ethylhexyl) phthalate are neither degraded abiotically nor by microorganisms. Hence, these PAEs can be leached and washed out of leaky landfills into the groundwater and thus continue to be a threat to the aquatic environment. Only a combined UV radiation/ozonation treatment is capable of fully destroying PAEs.


Author(s):  
Allen D. Uhler ◽  
Jeffery H. Hardenstine ◽  
Deborah A. Edwards ◽  
Guilherme R. Lotufo

AbstractPolychlorinated biphenyls (PCBs) were added to certain marine vessel bottom paints as a plasticizer to improve the adhesion and durability of the paint. The most common PCB formulation used to amend such paints was Aroclor 1254. Fugitive Aroclor-containing paint chips generated from vessel maintenance and repair operations represent a potential source of PCB contamination to sediments. Limited published studies indicate that Aroclor-containing paint is largely inert and exhibits low PCB leaching into water; however, the rate and degree of leaching of PCBs from paint chips have not been directly studied. This laboratory-based study evaluated the rate and extent of leaching of PCBs from paint chips into freshwater. The results of this investigation demonstrate that the rate of PCB dissolution from paint chips decreased rapidly and exponentially over time. Based on this study, it is estimated that the rate of leaching of PCBs from paint chips would cease after approximately 3 years of exposure to water. When all leachable PCBs were exhausted, it is estimated that less than 1% of the mass of PCBs in the paint chips was amenable to dissolution. The results of this experiment suggest that Aroclor-containing paint chips found in sediments are likely short-term sources of dissolved-phase PCB to pore or surface waters and that the majority of the PCBs in paint chips remain in the paint matrix and unavailable for partitioning into water. Graphic Abstract


2011 ◽  
Vol 10 (3) ◽  
pp. 149-154 ◽  
Author(s):  
Michiko NARAZAKI ◽  
Atsuomi KIMURA ◽  
Tetsuya WAKAYAMA ◽  
Hirohiko IMAI ◽  
Hideaki FUJIWARA

2012 ◽  
Vol 19 (03) ◽  
pp. 1250017 ◽  
Author(s):  
PENG LIU ◽  
YUANBIN ZHANG ◽  
HUI LUO ◽  
YUSHUANG HUO

In this study, Al–Ti–Co was used to improve the surface performance of pure Ti . Laser cladding is an important surface modification technique, which can be used to improve the surface performance of pure Ti . Laser cladding of the Al–Ti–Co + TiB2 pre-placed powders on pure Ti can form ceramics reinforced the composite coating, which improved the wear resistance of the substrate. Characteristics of the composite coating were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), microhardness and wear tests. And the laser-cladded coating can also have major dilution from the substrate. Due to the action of the fine grain strengthening and the phase constituent, the wear resistance and microhardness of pure Ti surface were greatly improved.


2014 ◽  
Vol 27 (12) ◽  
pp. 1490-1501 ◽  
Author(s):  
Kun Qing ◽  
John P. Mugler ◽  
Talissa A. Altes ◽  
Yun Jiang ◽  
Jaime F. Mata ◽  
...  

2007 ◽  
Vol 11 (1) ◽  
pp. 313-327 ◽  
Author(s):  
C. Neal

Abstract. Variations in concentration of yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm) and gadolinium (Gd) among rivers of eastern England and the border with Scotland are described in relation to the dissolved (<0.45 µM) fraction and acid-available particulate (AAP) fractions. The rivers cover a range of rural, agricultural and urban/industrial environments. Yttrium and the lanthanides show significant levels of both dissolved and acid-available particulate forms (typically about 40% in the dissolved form). For the dissolved phase, Y and the lanthanides are linearly correlated with each other and with iron: most of this dissolved component may be in a micro-particulate/colloidal form. The Y and lanthanide relationships show marked scatter and there are anomalously high La concentrations at times for the rivers Great Ouse, Thames and Wear that are probably linked to pollutant sources. For the Ouse, and especially for one of its tributaries, the Swale, relatively high Sm concentrations are probably associated with mineralisation within the catchment and contamination of the associated flood plain. For the AAP components, there are strong linear relationships with Y and the lanthanides across all the rivers. There is also a strong link between these AAP associated REE and AAP iron, although the scatter is greater and the industrial rivers have a lower lanthanide to iron ratio, probably due to iron-rich contaminants.


2012 ◽  
Vol 602-604 ◽  
pp. 421-425 ◽  
Author(s):  
Chang Sen Luo ◽  
Hong Luo ◽  
Xi Yang He

In this paper, the corrosion behavior was researched which was happen on the 304,321,316Lect. stainless steel materials in the analogue situation of calcining gas atmosphere of ammonium paramolybdate.The oxidized etch which happened on the sample’s surface, phase constituent and element content of the fracture surface, was analyzed by the means of SEM、XRD.The results showed that the phases of Fe2(MoO4)3,MoO3,MoO2.5(OH)0.5,Cr2O3,Cr2Ti5O13, Fe2O3,Fe3O4 ect. are contained on the surfaces of the 304,316L, 321 samples which are calcined. There is an inside oxidized corrosion layer in 304 316L. The oxidizing film is damaged and the oxygen penetrates into the base to form an oxidized layer. A thin and compact oxidation film was formed between 321 corrosion layer and the alloy interface, which have prevented the base from further corrosion, under this experiment conditions, this steel belonged to the inoxidizability materials. The coating deficiency of 321 steel is shallow; the particles of oxidate is thin and without inner corrosion; the weight gain rate of oxidized etch is slow (average rate 5.2×10-2mg/ (cm2•h)), the weight gain is less and corrosion resistance is fine.


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