scholarly journals Sediment coring and sedimentation analysis on Rasmussen Lake in Ethel's Woods Forest Preserve near Old Mill Creek, Illinois in 2005

Author(s):  
Timothy D. Straub ◽  
Donald P. Roseboom ◽  
Phillip G. Dennis
1967 ◽  
Vol 20 (2) ◽  
pp. 361-363 ◽  
Author(s):  
R. Brentani ◽  
M. Brentani ◽  
I. Raw

2013 ◽  
Vol 333-335 ◽  
pp. 2004-2009
Author(s):  
Lin Ling Jiang ◽  
Wei Mo ◽  
Xiao Jing Yang ◽  
Tian Li Xue ◽  
Shao Jian Ma

To better understand the sedimentation processes of bentonite, the sedimentation characteristic of bentonite suspension was studied by using the sedimentation analysis module of Dynamic Contact Angle Meter and Tensiometer. The results indicated that sedimentation characteristics of bentonite suspension were affected by the concentration and pH values of the suspension together with the dosage of dispersants. The natural sedimentation rates of bentonite suspension declined firstly with prolonging the sedimentation time and soon stabilized after about 50s. The sedimentation weight of particles hardly changed when the concentration ranged from 0.5% to 5.0%, while it increased significantly when ranged from 5.0% to 10.0%. The sedimentation weight and rate were relatively bigger at 4.4, 11.8 than that of 6.0, 7.9, and the maximum values appeared at pH11.8. Adding sodium pyrophosphate could improve the dispersibility of bentonite suspension.


2021 ◽  
pp. 153851322110462
Author(s):  
Natalie B. Vena

In 1916, the Forest Preserve District of Cook County began acquiring land to create a natural retreat for Chicagoans in that booming metropolitan region. Since district officials acquired many properties along county streams, water pollution soon interfered with their mission of creating an urban wilderness for recreational pleasure. To address the problem, in 1931, county leaders appointed the Clean Streams Advisory Committee that collaborated with forest preserve staff members to pressure polluters to clean-up their operations and to persuade enforcement agencies to prosecute ongoing offenders. They also lobbied the Public Works Administration to earmark New Deal funding for sewage treatment in Cook County. Their efforts suggest that early activism against water pollution in American cities emerged not only from efforts to ensure clean drinking water, but also struggles to protect nature. The interwar campaign to clean forest preserve streams anticipated the goals of the federal Clean Water Act (1972) to make all American waterways fishable and swimmable. The movement also preceded the burst of anti-pollution activism that historians have documented in U.S. suburbs after WWII and laid the groundwork for postwar efforts to mitigate water pollution in Cook County.


1993 ◽  
Vol 13 (8) ◽  
pp. 5020-5033
Author(s):  
V Gekeler ◽  
J Epple ◽  
G Kleymann ◽  
H Probst

Twelve-hour exposure of G1 Ehrlich ascites cells to controlled hypoxia (200 ppm of O2 at 1 bar) suppressed replicon initiation. Synchronous cycling, beginning with a normal S phase, was released by reoxygenation immediately. The addition of cycloheximide at reoxygenation largely resuppressed, after a short initial burst, succeeding replicon initiations. Alkaline sedimentation analysis of growing daughter strand DNA, DNA fiber autoradiography, and analysis of the newly formed DNA demonstrated that normal chain growth and DNA maturation (replicon termination) in the initially activated replicons continued in the presence of cycloheximide. After 2 to 3 h, a low level of cycloheximide-insensitive background replication emerged out of the then-ebbing single surge of activity of the initially released replicons.


2014 ◽  
Vol 74 (3 suppl 1) ◽  
pp. S078-S092 ◽  
Author(s):  
A Nemésio ◽  
JE Santos Junior

The orchid-bee faunas (Hymenoptera: Apidae: Euglossina) of the three largest forest remnants in the “Centro de Endemismo Pernambuco”, northeastern Brazil, namely Estação Ecológica de Murici (ESEC Murici), RPPN Frei Caneca, and a forest preserve belonging to Usina Serra Grande, in the states of Alagoas and Pernambuco, were surveyed using seventeen different scents as baits to attract orchid-bee males. Eight sites were established in the three preserves, where samplings were carried out using two protocols: insect netting and bait trapping. We collected 3,479 orchid-bee males belonging to 29 species during 160 hours in early October, 2012. Seven species were collected in the “Centro de Endemismo Pernambuco” for the first time. Richness proved to be one of the highest of the entire Atlantic Forest domain, and diversity in some sites, especially at ESEC Murici, revealed to be one of the highest in the Neotropics. Eulaema felipei Nemésio, 2010, a species previously recorded only at ESEC Murici, was found in no other preserve in the region and its conservation status is discussed.


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