scholarly journals On the Culture of the Plankton Diatom Thalassiosira grauida Cleve, in Artificial Sea-water

1914 ◽  
Vol 10 (3) ◽  
pp. 417-439 ◽  
Author(s):  
E. J. Allen
Keyword(s):  
Organic Compound ◽  
Culture Medium ◽  
Sea Water ◽  
Chemical Compounds ◽  
Distilled Water ◽  
Artificial Medium ◽  
Plant Life ◽  
Specific Substance ◽  
Vigorous Growth ◽  
Better Than

1. Attempts to obtain good cultures of Thalassiosira gravida in a purely artificial medium, made by dissolving in doubly distilled water Kahlbaum's pure chemicals in the proportions in which the salts occur in sea-water, adding nitrates, phosphates and iron according to Miquel's method and sterilizing the medium, have not succeeded.If, however, a small percentage of natural sea-water (less than 1 per cent will produce a result) be added to the artificial medium and the whole sterilized excellent cultures are obtained, which are often better than any which have been got when natural sea-water forms the foundation of the culture medium.The result appears to be due to some specific substance present in minute quantity in the natural sea-water which is essential to the vigorous growth of the diatoms. The nature of this substance it has not been possible to determine, but some evidence seems to suggest that it is a somewhat stable organic compound.Provided the 1 per cent of natural sea-water is added, the various constituents of the artificial sea-water forming the basis of the culture medium can be varied in amount within wide limits. The salinity of the medium can also be considerably altered without serious detriment to the cultures.The experiments recorded are of interest as furnishing another instance of the importance in food substances of minute traces of particular chemical compounds. They may also eventually throw light upon the nature of the conditions in the sea which are specially favourable to the production of plant life and therefore also of the animal life which that plant life sustains.

Reconstruction of Two-Dimensional Projections of GP 32*I

1981 ◽  
Vol 39 ◽  
pp. 38-39
Author(s):  
H.A. Cohen ◽  
W. Chiu ◽  
J. Hosoda
Keyword(s):  
Electron Microscopy ◽  
Molecular Weight ◽  
Uranyl Acetate ◽  
Distilled Water ◽  
Acetate Solution ◽  
Two Dimensional ◽  
Parent Molecule ◽  
T4 Bacteriophage ◽  
Electron Imaging ◽  
Better Than

GP 32 (molecular weight 35000) is a T4 bacteriophage protein that destabilizes the DNA helix. The fragment GP32*I (77% of the total weight), which destabilizes helices better than does the parent molecule, crystallizes as platelets thin enough for electron diffraction and electron imaging. In this paper we discuss the structure of this protein as revealed in images reconstructed from stained and unstained crystals.Crystals were prepared as previously described. Crystals for electron microscopy were pelleted from the buffer suspension, washed in distilled water, and resuspended in 1% glucose. Two lambda droplets were placed on grids over freshly evaporated carbon, allowed to sit for five minutes, and then were drained. Stained crystals were prepared the same way, except that prior to draining the droplet, two lambda of aqueous 1% uranyl acetate solution were applied for 20 seconds. Micrographs were produced using less than 2 e/Å2 for unstained crystals or less than 8 e/Å2 for stained crystals.

Examination for Degradation Paths of Butyltin Compounds in Natural Waters

1992 ◽  
Vol 25 (11) ◽  
pp. 117-124 ◽  
Author(s):  
N. Watanabe ◽  
S. Sakai ◽  
H. Takatsuki
Keyword(s):  
Glass Fiber ◽  
Half Life ◽  
Natural Waters ◽  
Sea Water ◽  
Degradation Process ◽  
Distilled Water ◽  
Degradation Rates ◽  
Clean Area ◽  
Butyltin Compounds ◽  
Sun Light

Examination of individual degradation paths (biodegradation and photolysis) of butyltin compounds (especially tributyltin: TBT) in natural waters was performed. Biodegradation of TBT and dibutyltin (DBT) in an unfiltered sea water in summer is rather fast; their half life is about a week. But pretreatment with glass fiber filter makes the half life of TBT much longer (about 80 days). Photolysis of TBT in sea water by sun light is rapid (half life is about 0.5 days), and faster than in distilled water or in fresh water. Degradation rates of each process for TBT are calculated in various conditions of sea water, and contribution rates are compared. Biodegradation will be the main degradation process in an “SS-rich” area such as a marina, but photolysis will exceed that in a “clean” area. Over all half lives of TBT in sea water vary from 6 days to 127 days considering seasons and presence of SS.

Specific heat of mixtures of kaolin with sea water or distilled water for their use in thermotherapy

2017 ◽  
Vol 130 (1) ◽  
pp. 479-484 ◽  
Author(s):  
M. M. Mato ◽  
L. M. Casás ◽  
J. L. Legido ◽  
C. Gómez ◽  
L. Mourelle ◽  
...  
Keyword(s):  
Specific Heat ◽  
Sea Water ◽  
Distilled Water

Taste by Touch: Some Experiments with Octopus

1963 ◽  
Vol 40 (1) ◽  
pp. 187-193
Author(s):  
M. J. WELLS
Keyword(s):  
Hydrochloric Acid ◽  
Fresh Water ◽  
Sea Water ◽  
Olfactory Organ ◽  
Distilled Water ◽  
Quinine Sulphate ◽  
Human Tongue ◽  
Half Strength

1. A method of teaching Octopus chemotactile discriminations is described. 2. The animals can be shown to be capable of distinguishing by touch between porous objects soaked in plain sea water and sea water with hydrochloric acid, sucrose or quinine sulphate added. 3. They can detect these substances in concentrations at least 100 times as dilute as the human tongue is capable of detecting them in distilled water. 4. They can be trained to distinguish between equimolar (0.2 mM) solutions of hydrochloric acid, sucrose and quinine. 5. They can also be trained to distinguish between sea water and fresh water or half-strength sea water or sea water with twice the usual quantity of salt. 6. The function of the ‘olfactory organ’ is discussed. 7. Chemotactile learning is discussed in relation to the means by which Octopus finds its way about the territory around its ‘home’

Experiments on Substrate Selection by Corophium Species: Films and Bacteria on Sand Particles

1964 ◽  
Vol 41 (3) ◽  
pp. 499-511
Author(s):  
P. S. MEADOWS
Keyword(s):  
Ionic Strength ◽  
Sea Water ◽  
Distilled Water ◽  
Substrate Selection ◽  
Corophium Volutator ◽  
Simple Method ◽  
Substrate Preferences ◽  
Solutions Of Electrolytes ◽  
Sand Particles ◽  
Micro Organisms

1. A simple method is described for determining the substrate preferences of Corophium volutator (Pallas) and Corophium arenarium Crawford. 2. If offered a choice of its own substrate with that of the other species each prefers its own. 3. Level of illumination and colour of substrate have little effect on choice. An animal's size and hence its age has little effect on its substrate preferences. 4. C. volutator prefers a substrate previously maintained under anaerobic conditions, C. arenarium vice versa. 5. Treatments which kill, inactivate, or remove micro-organisms render sands unattractive to Corophium. These include boiling, acid-cleaning, drying, and soaking in fixatives or distilled water. Attempts to make these sands attractive again failed. 6. Distilled water, and solutions of the non-electrolytes sucrose and glycerol at the same osmotic pressure as sea water, induce many bacteria to desorb from sand particles; smaller numbers are desorbed in the presence of solutions of electrolytes at the same ionic strength as sea water (NaCl, Na2SO4, KC1, MgSO4, MgCl2, CaCl2). Of all these, only distilled water and solutions of MgCl2 and CaCl2 reduce the attractive properties of sands. Hence the loss of bacteria from the surface of sand grains, though related to the ionic strength and composition of the medium, is not necessarily associated with a substrate becoming unattractive.

scholarly journals Chemical Compound of Terminalia Catappa L. as Hemostatic Agents in Post Tooth Extraction

2021 ◽  
Author(s):  
Ni Made Sirat ◽  
Asep Arifin Senjaya
Keyword(s):  
Antioxidant Activity ◽  
Tooth Extraction ◽  
Activity Index ◽  
Water Extract ◽  
Tree Height ◽  
Ethanol Extract ◽  
Chemical Compounds ◽  
Distilled Water ◽  
Terminalia Catappa ◽  
Herbal Plants

Terminalia catappa L. is one of the herbal plants that contain flavonoids that play a role in wound healing including to bleeding after tooth extraction. The aim of our study was to identify the chemical compounds contained in Terminalia catappa L. leaves. This type of research was experimental. The sample in this study was the leaves of Terminalia catappa number 3-6 from the base, at a tree height of 6 meters picked as much as 6 kilograms. Data analysis qualitatively and quantitatively. The highest content in ethanol extract of Terminalia catappa L of saponins and alkaloids were fractioned with distilled water and the lowest content were fractioned with hexane. Meanwhile distilled water is also used to fractioned the highest content of tannins and phenol. While ethyl acetate was used to fractioned the lowest content of tannins and the highest content of flavonoid. The lowest flavonoid in distilled water extract was fractioned using hexane. For the lowest content of phenol was fractioned using hexane. The results show the highest content of saponins is 3,787.80 mg/100g, the lowest is 166.67 mg/100g. The highest content of Alkaloids is 1,798.57 mg/100g, and the lowest is 576.80 mg/100g. The highest content of tannins is 53,140.72 mg/100g, the lowest is 8,391,803 mg/100g. The highest content of flavonoids is 2,5964.14 mg/100g, the lowest flavonoid is 462.84 mg/100g. The highest content of phenol 29,968.05 mg/100g, the lowest is 225.46 mg/100g. The highest antioxidant activity with AAI (Antioxidant Activity Index) obtains value of 0.36. This shows the moderate antioxidant ability. Terminalia catappa L. contain saponins, alkaloids, tannins, flavonoids, and triterpenoids. The active compound of Terminalia catappa L will generally be produced optimally if a polar solvent is used.

scholarly journals Effect Use of Two Chemical Compounds Sodium Nitrate and Sodium Silicate as Corrosion Inhibitor to Steel Reinforcement

2019 ◽  
Vol 14 (2) ◽  
pp. 123-128
Author(s):  
Sarah Kareem Mohammed
Keyword(s):  
Corrosion Rate ◽  
Sodium Silicate ◽  
Electrolyte Solution ◽  
Sodium Nitrite ◽  
Corrosion Inhibitors ◽  
Sea Water ◽  
Chemical Compounds ◽  
Steel Sample ◽  
Steel Reinforcement ◽  
Corrosion Of Steel

Corrosion of steel reinforcement is one of the biggest problems facing all countries in the world like bridges in the beach area and marine constructions which lead to study these problems and apply some economical solutions. According to the high cost of repair for these constructions, were studied the effect of using kind of chemical compounds sodium nitrite(NaNO2) and sodium silicate(Na2SiO3) as corrosion inhibitors admixture for steel bars that immersed partially in electrolyte solution (water + sodium chloride in 3% conc.) (Approximately similar to the concentration of salt in sea water). The two inhibitors above added each one to the electrolyte solution at concentrations (0.5%, 1% and 2%) for both of them.      The results were  corrosion rate for steel sample that's immersed partially in salt solution was higher than corrosion rate of steel bar that's immersed partially in electrolyte solution with inhibitors  also the two corrosion inhibitors (sodium nitrite and sodium silicate) that added to the electrolyte solution were working successfully to prevent and inhibit the corrosion by using weight loss technique with best percent of 0.5% sodium nitrite ( efficiency 94.1% ) and best percent of 2% sodium silicate ( efficiency 92.5%).

The role of sodium chloride in the process of induction by lithium chloride in cells of the Rana pipiens gastrula

Development ◽  
1968 ◽  
Vol 19 (3) ◽  
pp. 387-396
Author(s):  
Lester G. Barth ◽  
Lucena J. Barth
Keyword(s):  
Sodium Chloride ◽  
Culture Medium ◽  
Rana Pipiens ◽  
Divalent Cations ◽  
Pigment Cells ◽  
Distilled Water ◽  
Sodium Ions ◽  
Monovalent Cations ◽  
High Concentration

A study of the effects of a series of monovalent cations, Li+, Na+ and K+, and a series of divalent cations, Mn2+, Ca2+ and Mg2+, upon small aggregates of cells taken from the presumptive epidermis of Rana pipiens gastrulae revealed that these ions induce nerve and pigment cells (Barth, 1965). The effectiveness of both series of ions as inductors was similar to their effects on decreasing the electrophoretic mobility of DNA as determined by Ross & Scruggs (1964). When it was found that sucrose in glass-distilled water also would induce nerve and pigment cells the role of ions as inductors came under closer scrutiny. A study of the nature of the induction by sucrose revealed that a relatively high concentration of sodium ions was necessary in the culture medium used after sucrose treatment (Barth, 1966).

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