ELECTROLYSIS OF SEA WATER, OF SEA FORTIFIED WITH SALT, AND FRESH (TAP) WATER FORTIFIED WITH SALT

1958 ◽  
Author(s):  
T. ROE ◽  
HANNA JR. ◽  
HOCHMAN A. E. ◽  
H.
Keyword(s):  
Sea Water ◽  
Tap Water

On the Vitelline Membrane of the Egg of Psammechinus Miliaris and of Teredo Norvegica

1932 ◽  
Vol 9 (1) ◽  
pp. 93-106
Author(s):  
A. D. HOBSON
Keyword(s):  
Sea Water ◽  
Tap Water ◽  
Elastic Solid ◽  
Vitelline Membrane ◽  
Hypertonic Solution ◽  
Perivitelline Space ◽  
Free Zone ◽  
Hypertonic Solutions ◽  
Psammechinus Miliaris ◽  
Entire Cell

I. Direct microscopic examination of the unfertilised eggs of Psammechinus miliaris and Teredo norvegica merely shows the existence of a thin, granule-free zone covering the surface. Whether this is continuous with the general cytoplasm or not cannot be made out with certainty by direct observation. 2. A cone of clear material can be drawn out from the surface of the unfertilised egg of both species by means of the microdissection needle. A definite membrane cannot be separated in this way. 3. Hypertonic solutions cause the egg of Psammechinus to shrink smoothly at first and later to become wrinkled. This is consistent with the view that the egg is surrounded by an elastic, solid layer which is normally in a state of tension. 4. Cytolysis of the egg of Psammechinus in tap water is not accompanied by bursting. The egg swells and is perfectly smooth and spherical when cytolysis is completed. This points to the existence of an elastic, solid surface layer. 5. Plasmolysis of the egg of Teredo is of the type here called "polyhedral."The irregular shape of the egg in the hypertonic solution is only temporary, as a clear membrane separates from the concave surfaces and the egg then becomes more or less spherical. 6. The protoplasm of the plasmolysed egg of Teredo behaves as a viscous fluid. 7. Cytolysis of the egg of Teredo in tap water is accompanied by bursting and dispersion of the entire cell contents. A crumpled membrane alone remains. 8. It is concluded that the unfertilised egg of both Teredo norvegica and Psammechinus miliaris is surrounded by an elastic vitelline membrane which is much a Vitelline Membrane of the Egg of P. miliaris and of T. norvegica 105 thicker in the former than in the latter. The vitelline membrane in both cases is tightly attached to the egg surface. 9 . In calcium-free sea water the fertilisation membrane is elevated normally in Psammechinus miliaris. It does not harden, however, and gradually sinks back on to the surface of the egg owing, apparently, to the loss by diffusion of the osmotically active substance in the perivitelline space. It can be elevated a second time by puncturing the surface of the egg and allowing some of the cell contents to penetrate into the perivitelline space. 10. It is suggested that one action of hypertonic solutions in inducing artificial parthenogenesis may be to cause a loosening of the attachment of the vitelline membrane to the egg surface.

An experimental study of the scattering of light by natural waters

1952 ◽  
Vol 140 (900) ◽  
pp. 321-338 ◽  
Keyword(s):  
Surface Water ◽  
Natural Waters ◽  
Cold Water ◽  
Sea Water ◽  
Tap Water ◽  
Wave Length ◽  
Average Pore ◽  
Forward Scatter ◽  
Back Scattering ◽  
Similar Sample

A blue-sensitive multiplier phototube was used to measure light scattered from a parallel beam in distilled, tap and sea water, the first named serving as a check upon errors from extraneous sources of light. Forward and back scatter are closely the same for distilled water, but with natural waters by far the greater part of the effect occurs through angles less than 25°. A minimum is found for a deviation of about 110°, back scattering increasing somewhat for greater angles. The relative importance of forward scatter increases with turbidity, and in sea water about three-quarters of the effect is due to matter removable by filtration through a collodion filter of average pore diameter 1 μ or by sedimentation; further passage through 0·6 and 0·2 μ filters produces little change. Scattering is greater in blue light. Plymouth tap water scatters more than surface coastal water and the latter more than surface water 20 miles out, station E 1. Surface water scatters more than deeper—the water column being remarkably homogeneous even when a well-marked thermocline had existed for weeks, but a small increase was detectable at the top of the cold water. E 1 surface water increased in scattering between August and January, and decreased till May. Deep water showed little change. Extinction due to scattering between 20 and 155° amounted to less than one-sixth of that found for a similar sample with a Pulfrich photometer, so probably much scattering occurs below 20°. This explains why Pulfrich extinctions are so much greater than vertical extinction coefficients found in the sea. The preponderance of forward scattering within the range 20 to 155° and the effects of filtration suggest that such scattering is due chiefly to refraction through transparent mineral particles, large compared with the wave-length of light. The refractive index of organic matter is too near that of water to produce refraction through angles as large as 20°. Such matter may, however, be responsible for some of the scattering through smaller angles which apparently accounts for most of the turbidity found with the Pulfrich photometer.

scholarly journals 908 PB 533 STUDIES ON NATURE OF SALT TOLERANCE IN OKRA

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 564b-564
Author(s):  
Kh. A. Okasha ◽  
R. M. Helal
Keyword(s):  
Salt Tolerance ◽  
Seed Germination ◽  
Plant Development ◽  
Sea Water ◽  
Saline Water ◽  
Tap Water ◽  
Total Yield ◽  
Gold Coast ◽  
Electronic Conductivities ◽  
High Level

Salt tolerance of four okra cutivars namely : white velvet ; Gold coast ; Balady and Eskandarani, were investigated during three different stages of plant development namely : seed germination, seedling and reproductive stages. At both first and second stages of plant development various concentrations of sea water (diluted with tap water) were used for irrigation while at the third stage, various saline water with different electronic conductivities were used for irrigation Results of these studies revealed that salinity reduced and delayed seed germination At this stage, white velvet cv. appeared to be tolerant to salinity. At the seedling stage, salinity generally reduced hash weight of plant for all tested cuitivars and Gold coast was the lead affected one At the reproductive stage, salinity reduced plant growth and total yield/plant but with different degrees depending upon cultivar In this respect, yield of both Gold coast and Balady was not greatly reduced at the high level of salinity The anatomical studies showed that salinity reduced xylem and phloem elements in okra roots depending upon both salinity level and cultivar Generally, the obtained results suggest that both Gold coast and Balady okra cultivars can considered as tolerant genotypes to salinity and recommended for cultivation in both and and semi-arid lands where salinity is considered a potential problem

scholarly journals Lead Ions Removal from Natural Water Samples by Nano-Mint Waste as Benign Low Cost Biosorbent

2018 ◽  
Vol 3 (2) ◽  
pp. 116-126
Author(s):  
Tamer H. A. Hasanin ◽  
Salwa A. Ahmed ◽  
Taghreed B. Ebrahim
Keyword(s):  
Natural Water ◽  
Water Samples ◽  
Metal Ion ◽  
Sea Water ◽  
Tap Water ◽  
Low Cost ◽  
Lead Removal ◽  
Lead Uptake ◽  
Natural Water Samples ◽  
Uptake Process

Nano mint waste (NMW) was used as a low-cost nano biosorbent and efficient Pb(II) remover. pH, contact time, biosorbent dose, and concentration of metal ion were optimized using batch technique to optimize maximum capacity of this new biosorbent. NMW was characterized using FT-IR, SEM, TEM, and XRD analyses. The experimental Pb(II) adsorption data by NMW were agreed with both Freundlich and Langmuir models with maximum boisorption capacity of 2.13 mmolg-1 (441.336 mgg-1). In addition, values of lead uptake at different time vaues was best fitted with the kinetic pseudo-second order model. It will be notable that, good data resulted from the kinetic experiments study confirmed a fast accessibility of the Pb(II) to the biosorbent surface, get to equilibrium within 30 seconds. On the other hand, it was observed that, the developed method, was investigated for measuring of Pb(II) with a certain spiked amounts in natural water samples as ground water (GW), sea water (SW), drinking tap water (DTW), natural drinking water (NDW), Nile River water (NRW) and waste water (WW). The good results obtained with high recovered quantitatively using batch experiments, without matrix interferences. Considering its cheap source, environmentally friendly, economic and fast uptake process, NMW can be used as benign nano biosorbent for lead removal from real water samples.

scholarly journals Penentuan Pelarut Terbaik pada Ekstraksi Tanin Kulit Kayu Akasia dan Pengaruhnya Sebagai Inhibitor Laju Korosi pada Baja Karbon

2020 ◽  
Vol 4 (1) ◽  
pp. 7
Author(s):  
Ayu Ratna Permanasari ◽  
Tri Reksa Saputra ◽  
Aprillia Nurul’Aina ◽  
Salma Liska
Keyword(s):  
Carbon Steel ◽  
Corrosion Inhibitor ◽  
Sea Water ◽  
Tap Water ◽  
Extraction Process ◽  
Bark Extract ◽  
Corrosive Media ◽  
Rotary Evaporator ◽  
Tannin Concentration ◽  
Reduction Methods

Peralatan industri dari baja karbon yang berkontak langsung dengan lingkungan lama kelamaan akan terkorosi. Laju korosi dapat diperlambat menggunakan inhibitor organik senyawa tanin dari pohon akasia. Tanin diperoleh dari proses ekstraksi menggunakan metanol dan etanol. Tujuan dari penelitian ini adalah menentukan pelarut terbaik dalam proses ekstraksi kulit kayu akasia berdasarkan kandungan tanin terbesar serta mempelajari pengaruh tanin sebagai inhibitor korosi pada baja karbon dalam media korosif melalui metode pengurangan berat. Proses ekstraksi menggunakan metode maserasi pada suhu ruang selama dua jam dengan perbandingan padatan:pelarut adalah 1:10. Pelarut yang digunakan adalah etanol dan metanol. Ekstrak dievaporasi dalam rotary evaporator pada suhu 50 oC, tekanan 100 mbar hingga membentuk pasta. Ekstrak kulit kayu ditambahkan sebagai inhibitor dalam media korosif H2SO4 0,5 M; HCl 0,5 M; air laut, dan air tanah dengan penambahan konsentrasi inhibitor sebesar 4%, 6% dan 8% (b/v). Perendaman dilakukan selama 12, 24, 36, 48, 60 dan 72 jam. Metanol merupakan pelarut yang lebih baik daripada etanol dengan perolehan yield 4,57% dan konsentrasi tanin sebesar 2,768 ppm. Tanin dalam ekstrak kulit kayu akasia cocok digunakan sebagai inhibitor korosi pada media asam seperti H2SO4 0,5 M dan HCl 0,5 M dengan perolehan efisiensi tertinggi secara berturut-turut adalah 81,20 % dan 53,06%.Carbon steel in industrial equipment which direct contact with the environment will eventually be corroded. The rate of corrosion could be slowed by organic inhibitors of tannin compounds contained from acacia trees. Tannins were obtained from the extraction process using methanol and ethanol. The aims of this research were to determine the best solvent in the extraction process of acacia bark based on the largest tannin content and to study the effect of tannin as a corrosion inhibitor on carbon steel in the corrosive media through weight reduction methods. The extraction process used maceration at room temperature for two hours with a solid:solvent ratio of 1:10. The solvents were ethanol and methanol. The extract was evaporated in a rotary evaporator at 50 oC, 100 mbar became a paste form. Bark extract was added as an inhibitor in 0.5 M H2SO4 corrosive media; HCl 0.5 M; sea water, and tap water with the addition of inhibitor concentrations of 4%, 6% and 8% (w /v). Immersion was carried out for 12, 24, 36, 48, 60 and 72 hours. Methanol was a better solvent than ethanol with a yield of 4.57% and tannin concentration of 2.768 ppm. Tannin in acacia bark extract is suitable to be used as a corrosion inhibitor in acidic media such as H2SO4 0.5 M and 0.5 M HCl with the highest efficiency gains are 81.20% and 53.06%, respectively.

scholarly journals Mechanical Properties, Microstructure, and Chloride Content of Alkali-Activated Fly Ash Paste Made with Sea Water

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1467
Author(s):  
Salman Siddique ◽  
Jeong Gook Jang
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Sea Water ◽  
Tap Water ◽  
Pure Water ◽  
Degree Of Polymerization ◽  
29Si Nmr ◽  
Water Based ◽  
Ft Ir ◽  
Alkali Activated

The aim of the present study is to investigate the potential of sea water as a feasible alternative to produce alkali-activated fly ash material. The alkali-activated fly ash binder was fabricated by employing conventional pure water, tap water, and sea water based alkali activating solution. The characteristics of alkali-activated materials were examined by employing compressive strength, mercury intrusion porosimetry, XRD, FT-IR, and 29Si NMR along with ion chromatography for chloride immobilization. The results provided new insights demonstrating that sea water can be effectively used to produce alkali activated fly ash material. The presence of chloride in sea water contributed to increase compressive strength, refine microstructure, and mineralogical characteristics. Furthermore, a higher degree of polymerization on the sea water-based sample was observed by FT-IR and 29Si NMR analysis. However, the higher amount of free chloride ion even after immobilization in sea water-based alkali-activated material, should be considered before application in reinforced structural elements.

An SEM and EDS study of secretions from the leaves of two halophytes

1994 ◽  
Vol 52 ◽  
pp. 340-341
Author(s):  
Yougasphree Naidoo ◽  
Michael A. Gregory ◽  
Gonasagren Naidoo
Keyword(s):  
Salt Marsh ◽  
Nutrient Solution ◽  
Sea Water ◽  
Tap Water ◽  
Coarse Sand ◽  
Salt Glands ◽  
Sporobolus Virginicus ◽  
Crystalline Deposits ◽  
Saline Habitats ◽  
Intertidal Marshes

Salt glands are secretory organs that occur in several angiosperm families including the Plumbaginaceae and Poaceae. They are particularly prevalent on the leaves of plants growing in saline habitats where by the secretion of ions, they prevent toxic levels of salts from accumulating in their tissues. Whether different species of halophytes containing morphologically disparate glands preferentially secrete different cocktails of ions is not known. This question was addressed by employing SEM and EDS to determine the morphology and elemental constituents of crystalline deposits over the salt glands of two species of salt marsh halophytes: Limonium scabrum (Thunb.) Kuntze (Plumbaginaceae) and Sporobolus virginicus (L.) Kunth (Poaceae).The two halophytes, collected from intertidal marshes and cultivated in a mixture of coarse sand and compost (3:1 by volume) were irrigated daily with tap water and fertilised every two weeks with full strength Hoagland’s nutrient solution. Plants were watered weekly for 3 months with 50 mol m−3 NaCl supplied as diluted sea water.

The Effect of Fertilisation on the Permeability to Water and on Certain Other Properties of the Surface of the Egg of Psammechinus Miliaris

1932 ◽  
Vol 9 (1) ◽  
pp. 69-92
Author(s):  
A. D. HOBSON
Keyword(s):  
Sea Water ◽  
Tap Water ◽  
Surrounding Medium ◽  
Volume Changes ◽  
Single Experiment ◽  
Stage Of Development ◽  
Maximum Value ◽  
Hypertonic Solutions ◽  
Psammechinus Miliaris

1. A photographic method is described for recording volume changes in seaurchin eggs. 2. The behaviour of the eggs of Psammechinus miliaris, both before and at various intervals after fertilisation, in relation to osmotic changes in the surrounding medium have been investigated. 3. The rate of entrance of water from hypotonic sea water into the egg increases immediately after fertilisation takes place, rises to a first maximum at about 3 min. after fertilisation. It then falls to a comparatively low value at about 5 min. after fertilisation. After this the rate increases steadily to a maximum value which is reached about 35 min. after fertilisation. It remains steady until just before cleavage when, in the single experiment continued until this stage of development, it decreased very markedly. 4. The action of hypertonic solutions on the egg has been examined. Several types of plasmolysis occur and are characteristic of different stages in the development of the egg after fertilisation. The type of plasmolysis is determined principally by the physical properties of the egg surface. The plasmolysis method is of little use in this material for the determination of relative permeability to dissolved substances at different stages of development. 5. The rate of cytolysis in tap water has been investigated and its relation to permeability of the egg surface to water is considered. There is a susceptible period followed by one of resistance during the first 5-10 min. after fertilisation. The rate of cytolysis is conditioned, not only by the rate of entrance of water but also by the degree to which the cell surface will withstand stretching. The latter may be a significant factor. 6. The rate of Zytolysis in extremely hypertonic solutions of sea water + NaCl has been examined. It increases to a maximum at about 5-10 min. after fertilisation. Thereafter it decreases. Cytolysis in the unfertilised egg and just after fertilisation is a sudden process. Later it becomes more and more gradual and progresses slowly from the surface to the interior of the egg. The relation between the rate of cytolysis and permeability is uncertain.

Hibernation and Osmoregulation in the Diamondback Terrapin Malaclemys Centrata Centrata (Latreille)

1973 ◽  
Vol 59 (1) ◽  
pp. 45-51
Author(s):  
M. GILLES-BAILLIEN
Keyword(s):  
Osmotic Stress ◽  
Blood Plasma ◽  
Osmotic Pressure ◽  
Fresh Water ◽  
Seasonal Variations ◽  
Sea Water ◽  
Tap Water ◽  
The Other ◽  
Diamondback Terrapin ◽  
Diamondback Terrapins

1. Two batches of diamondback terrapins have been kept for a whole year, one in sea water the other in tap water, and seasonal variations have been recorded in the composition and osmotic pressure of the blood plasma. 2. All year round the sea-water animals have a higher osmotic pressure and higher concentrations of Na, K, Cl and urea than fresh-water animals. It is in July, however, that these differences are the least marked. 3. The seasonal variations recorded are linked in particular to the conditions of osmotic stress imposed by the environment. 4. The results are discussed within the framework of hibernation and of the evolution among chelonians from fresh water to sea water.

Sign in / Sign up

Export Citation Format

Share Document