The Precipitation of Calcium Carbonate on the Great Bahama Bank

1933 ◽  
Vol 70 (10) ◽  
pp. 455-466 ◽  
Author(s):  
Maurice Black
Keyword(s):  
New Jersey ◽  
Calcium Carbonate ◽  
Water Samples ◽  
Chlorine Content ◽  
The Bahamas ◽  
Chemical Laboratory ◽  
Great Bahama Bank ◽  
Andros Island ◽  
The University ◽  
Total Salinity

In the spring of 1930 the International Expedition to the Bahamas made several traverses over the shoals west of Andros Island in order to study the sedimentation of calcium carbonate in this region, and along three of these lines water samples were collected at regular intervals. The chlorine content of each of these samples was determined by the author in the Chemical Laboratory at the University of Princeton, New Jersey, and the total salinity was obtained by calculation.

scholarly journals VI. The algal sediments of Andros Island, Bahamas

1932 ◽  
Vol 222 (483-493) ◽  
pp. 165-192 ◽  
Keyword(s):  
Calcium Carbonate ◽  
Green Algae ◽  
The Bahamas ◽  
Blue Green Algae ◽  
Plant Life ◽  
Andros Island ◽  
Lower Palaeozoic

In the course of a geological reconnaissance of Andros Island, in the Bahamas, it was found that the lower forms of plant life, especially the Blue-green Algæ, play an important part in the process of sedimentation. In addition to those forms which actively contribute calcium carbonate to the sediment, there are other species which function primarily as sediment binders, without necessarily precipitating any lime themselves. Such sediment-binding algæ usually impart characteristic structures to the medium in which they grow; and in the interior of Andros, where such deposits are now accumulating over large areas, structures are being produced which are reminiscent of those found in some of the great limestone formations of the Lower Palaeozoic and Upper Precambrian. In view of this, and of the supposed algal origin of certain of these limestone structures, it is felt that a detailed description of the Bahaman sedi- merits will provide an example of a modem Cyanophyceous deposit, which, may prove useful for comparison with older limestones of similar structure.

Environment of calcium carbonate deposition west of Andros Island, Bahamas

10.3133/pp350 ◽  
1962 ◽  
Author(s):  
Preston E. Cloud ◽  
P.D. Blackmon ◽  
F.D. Sisler ◽  
Henry Kramer ◽  
J.H. Carpenter ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Carbonate Deposition ◽  
Andros Island ◽  
Calcium Carbonate Deposition

On the Thermo-electric Properties of Solid and Liquid Mercury

1902 ◽  
Vol 23 ◽  
pp. 15-15 ◽  
Author(s):  
W. Peddie ◽  
A. B. Shand
Keyword(s):  
Carbonic Acid ◽  
Large Mass ◽  
Electric Properties ◽  
Considerable Time ◽  
Chemical Laboratory ◽  
Thermo Electric ◽  
Liquid Mercury ◽  
Usual Manner ◽  
Solid Form ◽  
The University

AbstractBy means of a large quantity of solid carbonic acid, obtained from the University Chemical Laboratory, it was found possible to solidify, and maintain in the solid form for a considerable time, a large mass of mercury. Preliminary experiments made about a year ago, in the usual manner, by means of a triple circuit (iron, german silver, mercury), did not give results of a satisfactory kind. This was apparently due to the difficulty of maintaining steady, or steadily varying, temperatures.

Antibiotic susceptibility testing of bacteria in drinking water sources in Akungba‐Akoko, Ondo State, Nigeria

2011 ◽  
Vol 1 (4) ◽  
pp. 233-237
Author(s):  
A. O. Ajayi ◽  
N. F. Agangan
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Multiple Drug Resistance ◽  
Antibiotic Sensitivity ◽  
Water Sources ◽  
Resistant Bacteria ◽  
Multiple Drug ◽  
Antibiotic Resistant ◽  
Antibiotic Sensitivity Test ◽  
The University

In present investigation, the bacteriological analysis and antibiotic sensitivitypattern of drinking water samples collected from different sources ofAkungba Ã¢â‚¬ÂAkoko, Nigeria was done. The antibiotics mainly considered in ourstudy for determining the sensitivity were amongst the commonly used inthis area for treatment of infectious diseases. As a result, the bacteriologicalindex, especially coliform count was observed notably high with 72 x10 1 cfu/ml for stream sample and 26.4 x 10 1 cfu/ml for borehole sample. The majorbacterial isolates identified in the water samples were Staphylococcus sp,E.coli  Ã¢â‚¬Ânegative bacteria wereobserved showing 75% and 65% resistant to Septrin and Amoxicillin respectively.Also, multiple drug resistance was observed for many antibiotics.Therefore, the presence of high amount antibiotic resistant bacteria of clinicalimportance is reported in these water sources which are usually consumedby students and members of the University community. Hence, thisstudy necessitates the need for water treatment so that epidemics of waterbornebacterial disease can be averted in this region., Klebsiella sp, Pseudomonas sp., Enterococcus sp., Bacillus cereus andothers. With regards to the antibiotic sensitivity test, all isolates showed100% resistance to Ampicillin and Cloxacillin and 85.7% resistance to Zinnacef[a cephalosporin product]. However, the gram 

scholarly journals Isolation of Bacterial Pathogens from Borehole Water Sources within the University of Port Harcourt

2020 ◽  
pp. 39-44
Author(s):  
H. O. Stanley ◽  
C. N. Eze
Keyword(s):  
Water Samples ◽  
Bacterial Count ◽  
Water Sources ◽  
World Health ◽  
Coliform Bacteria ◽  
Adequate Treatment ◽  
Post Graduate ◽  
Port Harcourt ◽  
Borehole Water ◽  
The University

A study about the bacteriological and physicochemical quality of borehole water at the University of Port Harcourt was carried out. Eight water samples was pooled from NUH Block B (Under graduate Hostel), Nelson Mandela Block B (Undergraduate Hostel), Intercontinental Hostel (Post Graduate Hostel), Donald Ekong Block C (Post graduate Hostel), Clinical Hostel, Staff quarters (Opposite Uniport Bottling plant), Dan Etete (Undergraduate Hostel) and Gambiama Staff quarters designated as Sample 1 to sample 8 respectively. Physical examination was conducted to as the sanitary and hygiene practices within the collection area. It was observed that the undergraduate hostels had the least sanitary practice. Total counts of heterotrophic bacteria count showed that the highest bacterial count was recorded from Sample 2 with bacterial count of 2.3x104 CFU/ml while the least bacterial count was recorded from sample 8 with bacterial count of 3.0x102 CFU/ml. The isolated bacterial species from the water sources were identified as Bacillus sp., Micrococcus sp., E. coli., Serratia sp., Staphylococcus sp., Enterobacter sp., Citrobacter sp. The presence of coliform bacteria in the sampled water source does not comply with the World Health Organization (WHO) standard for coliform bacteria of zero total coliform per 100 ml of water. The borehole water samples collected had pH values within 5.9-6.85 which does not comply with the WHO recommended range for drinking water standards which should fall between ≥7 to ≤9.2. Nitrate concentration as observed amongst the eight water samples was below the WHO standard of 50mg/l. The Total dissolved solutes was below 0.01 in all the tested waters samples. This study has revealed that borehole water from sampled sources within the University of Port Harcourt is not fit for human consumption without adequate treatment.

scholarly journals The University Chemical Laboratory, Cambridge

Nature ◽  
1958 ◽  
Vol 182 (4645) ◽  
pp. 1280-1281
Author(s):  
F. G. MANN
Keyword(s):  
Chemical Laboratory ◽  
The University

Functionalization of C-H Bonds: The Baran Synthesis of Dihydroxyeudesmane

2011 ◽  
Author(s):  
Douglass Taber
Keyword(s):  
Columbia University ◽  
National Chemical Laboratory ◽  
Chemical Laboratory ◽  
Du Bois ◽  
Rh Catalyst ◽  
Hydride Abstraction ◽  
Mcgill University ◽  
Radical Removal ◽  
The University ◽  
Useful Yield

Arumugam Sudalai of the National Chemical Laboratory, Pune reported (Tetrahedron Lett. 2008, 49, 6401) a procedure for hydrocarbon iodination. With straight chain hydrocarbons, only secondary iodination was observed. Chao-Jun Li of McGill University uncovered (Adv. Synth. Cat. 2009, 351, 353) a procedure for direct hydrocarbon amination, converting cyclohexane 1 into the amine 3. Justin Du Bois of Stanford University established (Angew. Chem. Int. Ed. 2009, 48, 4513) a procedure for alkane hydroxylation, converting 4 selectively into the alcohol 6. The oxirane 8 usually also preferentially ozidizes methines, hydroxylating steroids at the C-14 position. Ruggero Curci of the University of Bari found (Tetrahedron Lett. 2008, 49, 5614) that the substrate 7 showed some C-14 hydroxylation, but also a useful yield of the ketone 9. The authors suggested that the C-7 acetoxy group may be deactivating the C-14 C-H. C-H bonds can also be converted directly to carbon-carbon bonds. Mark E. Wood of the University of Exeter found (Tetrahedron Lett. 2009, 50, 3400) that free-radical removal of iodine from 10 followed by intramolecular H-atom abstraction in the presence of the trapping agent 11 delivered 12 with good diastereo control. Professor Li observed (Angew. Chem. Int. Ed. 2008, 47, 6278) that under Ru catalysis, hydrocarbons such as 13 could be directly arylated. He also established (Tetrahedron Lett. 2008, 49, 5601) conditions for the direct aminoalkylation of hydrocarbons such as 13, to give 17. Huw M. L. Davies of Emory University converted (Synlett 2009, 151) the ester 4 to the homologated diester 19 in preparatively useful yield using the diazo ester 18, the precursor to a selective, push-pull stabilized carbene. Intramolecular bond formation to an unactivated C-H can be even more selective. Guoshen Liu of the Shanghai Institute of Organic Chemistry developed (Organic Lett. 2009, 11, 2707) an oxidative Pd system that cyclized 20 to the seven-membered ring lactam 21 . Professor Du Bois devised (J. Am. Chem. Soc. 2008 , 130, 9220) a Rh catalyst that effected allylic amination of 22, to give 23 with substantial enantiocontrol. Dalibor Sames of Columbia University designed (J. Am. Chem. Soc. 2009, 131, 402) a remarkable cascade approach to C-H functionalization. Exposure of 24 to Lewis acid led to intramolecular hydride abstraction. Cyclization of the resulting stabilized carbocation delivered the tetrahydropyan 25 with remarkable diastereocontrol.

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