scholarly journals THE PENETRATION OF STRONG ELECTROLYTES

1929 ◽  
Vol 12 (3) ◽  
pp. 427-433 ◽  
Author(s):  
W. C. Cooper ◽  
M. J. Dorcas ◽  
W. J. V. Osterhout
Keyword(s):  
Heavy Metals ◽  
Specific Gravity ◽  
Electrical Resistance ◽  
Sea Water ◽  
High Electrical Resistance ◽  
Other Substances ◽  
Alkaline Earths ◽  
Strong Electrolytes ◽  
Very High

The entrance of strong electrolytes into Valonia is very slow unless the cells are injured. This, together with the very high electrical resistance of the protoplasm, suggests that they may penetrate largely as undissociated molecules formed at the surface of the protoplasm by the collision of ions. Under favorable circumstances KCl may be absorbed to the extent of 3 x 10–8 mols per hour per sq. cm. of surface together with about 0.17 as much NaCl. Other substances which seem to penetrate to some extent are Li, Rb, Br, BrO3, I, IO3, and selenite. Little or no penetration is shown by SCN, ferricyanide, ferrocyanide, formate, salicylate, tungstate, seleniate, NO2, SO3, Sb, glycerophosphate, and many heavy metals and the alkaline earths. In sea water whose specific gravity had been increased by CsCl cells of Valonia floated for over a year and there was little or no penetration of Cs except as the result of injury. The penetration of NH4Cl decreases the specific gravity of the sap and causes the cells to float: under these circumstances they live indefinitely. It is probable that NH3 or NH4OH penetrates and is subsequently changed to NH4Cl. It would seem that if the sea contained a little more ammonia this would be a floating organism.

ЭКОЛОГО-ГЕОХИМИЧЕСКОЕ РАЙОНИРОВАНИЕ ТЕРРИТОРИИГ. БИРОБИДЖАНА ПО УРОВНЮ ЗАГРЯЗНЕНИЯ СНЕЖНОГО ПОКРОВА

2019 ◽  
Author(s):  
V.B. Kalmanova
Keyword(s):  
Heavy Metals ◽  
Snow Cover ◽  
Urban Area ◽  
Constructive Method ◽  
Comparative Characteristic ◽  
Ecological State ◽  
Sources Of Pollution ◽  
Mobile Sources ◽  
Arcview Gis ◽  
Very High

В статье представлены результаты исследования экологогеохимического состояния снежного покрова как индикатора качества атмосферного воздуха г. Биробиджана. Выявлены основные природные и антропогенные факторы, предопределяющие экологическое состояние городской территории в зимний период (климатические, планировочная структура, стационарные и мобильные источники загрязнения). Определено, что выбросы основных загрязнителей во время отопительного сезона превышает летний в 6,5 раз. Проведены геохимические исследования снежного покрова на 60 экспериментальных площадках, заложенных в различных функциональных зонах города. Выявлено значительное превышение тяжелых металлов над фоновым уровнем: железа до 60, марганца до 50, меди до 40, цинка до 20, никеля до 12, свинца до 10, кобальта до 6 раз. С 2003 по 2018 годы содержание химических элементов в снеге увеличилось в 2 раза за счет мобильных источников загрязнения, ТЭЦ, котельных. Проведена сравнительная характеристика накопления тяжелых металлов в снеге за 2003 и 2018 годы и установлен ранжированный ряд загрязняющих токсичных веществ. Разработана шкала оценки загрязнения депонирующих сред по суммарному показателю концентрации тяжелых металлов, согласно которой в Биробиджане выявлено 5 уровней загрязнения снежного покрова. В целом экологическое состояние урбанизированной территории признано неудовлетворительным (8 площади территории относится к очень высокому, 14 к высокому, 21 к выше среднему, 27 к среднему уровням загрязнения, 30 к относительно чистым районам города). По полученным результатам разработана карта в программе ArcView GIS Экологогеохимическое районирование территории г. Биробиджана по уровню загрязнения снежного покрова с выделением наиболее загрязненных участков (70 от общей площади города является загрязненной). По результатам проведенных исследований предложены конструктивные методы планирования урбанизированной территории с целью улучшения ее экологического состояния: проведение геомониторинга (контроль загрязнения снежного покрова и своевременный его вывоз на специально оборудованные полигоны). Snow cover is taken as an indicator of air quality using Birobidzhan, a middlesize city in the Russian Far East, as a case study. The main natural and manmade determinants influencing the ecological state of the urban area in winter are identified: climate, a planning structure, and the stationary and mobile sources of pollution. During the heating season the emission of major pollutants exceeds the summer level by 6.5 times. The geochemical study of snow cover was performed at 60 experimental sites in different functional urban areas. A significant excess of heavy metals over the regional background level was revealed: iron up to 60 times, manganese up to 50, copper up to 40, zinc up to 20 , nickel up to 12, lead up to 10, cobalt up to 6 times. From 2003 to 2018 the content of chemical elements in snow increased in 2 times due to the mobile sources of pollution, thermal power plants, and boilers. The comparative characteristic of accumulation of heavy metals in snow for 2003 and 2018 is carried out, and the ranked number of polluting toxic substances is established. The scale of pollution assessment in depositing environments was developed using the cumulative indicator of heavy metal concentration. Five levels of snow cover pollution are found in Birobidzhan: low, moderate, above moderate, high and very high. As a whole, the ecological state of the urban area is considered as unsatisfactory (8 of the area with a very high level of pollution, 14 with high, 21 above moderate, 27 a moderate level of pollution, 30 a relatively clean area). According to the results, a map was developed in the ArcView GIS program Ecological and geochemical zoning of Birobidzhan, using the level of the snow cover pollution with the allocation of the most polluted areas (70 of the total area of the city is polluted). According to the results, a constructive method of planning in an urban area is proposed in order to improve its environmental condition: geomonitoring as a control of pollution in snow cover and its prompt removal to specially equipped landfills.

MONEL ALLOY 401

Alloy Digest ◽  
1970 ◽  
Vol 19 (6) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Tensile Properties ◽  
Temperature Coefficient ◽  
Nickel Alloy ◽  
Electrical Resistance ◽  
Heat Treating ◽  
High Electrical Resistance ◽  
Good Corrosion Resistance ◽  
Copper Nickel Alloy

Abstract MONEL alloy 401 is a copper-nickel alloy with high electrical resistance and is used primarily in specialized electrical and electronic applications. It has a negligible temperature coefficient of electrical resistance and good corrosion resistance. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming, heat treating, and machining. Filing Code: Cu-216. Producer or source: Huntington Alloy Products Division.

III. On a new substance occurring in the urine of a patient with mollities ossium

1848 ◽  
Vol 138 ◽  
pp. 55-62 ◽  
Keyword(s):  
Nitric Acid ◽  
Specific Gravity ◽  
Test Tube ◽  
High Specific Gravity ◽  
Solid Substance ◽  
Semi Solid ◽  
Very High

On the 1st of November 1845 I received from Dr. Watson the following note, with a test tube containing a thick, yellow, semi-solid substance:—“The tube contains urine of very high specific gravity; when boiled it becomes highly opake; on the addition of nitric acid it effervesces, assumes a reddish hue, becomes quite clear, but, as it cools, assumes the consistence and appearance which you see: heat reliquifies it. What is it ?” A few hours afterwards a specimen of the same urine, passed by a grocer forty-seven years of age, who had been out of health for thirteen months, was sent to me by Dr. MacIntyre. He being in attendance on the case with Dr. Watson, had two days previously first observed the peculiar reactions of the urine.

scholarly journals Fatigue crack initiation and growth on a steel in the very high cycle regime with sea water corrosion

2010 ◽  
Vol 77 (11) ◽  
pp. 1953-1962 ◽  
Author(s):  
Thierry Palin-Luc ◽  
Rubén Pérez-Mora ◽  
Claude Bathias ◽  
Gonzalo Domínguez ◽  
Paul C. Paris ◽  
...  
Keyword(s):  
Fatigue Crack ◽  
Crack Initiation ◽  
Sea Water ◽  
Fatigue Crack Initiation ◽  
Very High

The Monitoring and Ecological Evaluation of Beng River Sediment for Heavy Metals (Hg,Pb,Cr)

2014 ◽  
Vol 675-677 ◽  
pp. 345-349
Author(s):  
Ji Cai Qiu
Keyword(s):  
Heavy Metals ◽  
Risk Index ◽  
Potential Ecological Risk ◽  
Index Method ◽  
Ecological Risk Index ◽  
Ecological Evaluation ◽  
Main Research ◽  
Bottom Mud ◽  
River Reach ◽  
Very High

In order to analysis the Heavy metals in the bottom mud at beng river, we put the river reach between the bridge of beng river beside the er’huang road and the bridge beside the yin’meng road as the main research object, survey 14 transects of bottom mud from three indications (Hg,Pb,Cr) of the river and build a relate standards about the pollution of bottom mud depend on the domestic standards, in this paper, we use the potential ecological risk index method which was putted forward by Swedish scientists Hakanson as the criterion of the pollution about heavy metals in the mud. The results show that: at the rive reach mentioned above, we found there are very high heavy metals content in the bottom mud.

scholarly journals CALCULATIONS OF BIOELECTRIC POTENTIALS

1939 ◽  
Vol 23 (1) ◽  
pp. 53-57 ◽  
Author(s):  
W. J. V. Osterhout
Keyword(s):  
Alkali Metals ◽  
Sea Water ◽  
Low Ph ◽  
Electrical Behavior ◽  
Low Concentrations ◽  
Alkaline Earths ◽  
Bioelectric Potentials

Interest in the study of Halicystis and of Valonia has been stimulated by discoveries of marked contrasts and striking similarities existing side by side. This is illustrated by new experiments with the alkali metals and alkaline earths. In Halicystis the apparent mobilities of K+, Rb+, Cs+, and Li+ (calculated by means of Henderson's equation from changes in P.D. produced by replacing sea water by a mixture of equal parts of sea water and 0.6 M of various chlorides) are as follows, uK, = 16, uRb = 16, uCs = 4.4, and uLi = 0.2; uNa is taken as 0.2. These values resemble those in Valonia except that in the latter uCs is about 0.2. No calculation is made for uNHNH4, because in these experiments even at low pH so much NH3 is present that the sign of the P.D. may reverse. This does not happen with Valonia. According to Blinks, NH4+ at pH 5 in low concentrations acts like K+. The calculation gives uMg = 1.9 which is similar to the value found for Valonia. No calculation can be made for CaCl2 since it produces protoplasmic alterations and in consequence Henderson's equation does not apply. This differs from Valonia. Evidently these plants agree closely in some aspects of electrical behavior but differ widely in others.

Organic and metallic pollutants in water treatment and natural wetlands: a review

2012 ◽  
Vol 65 (1) ◽  
pp. 76-99 ◽  
Author(s):  
K. Haarstad ◽  
H. J. Bavor ◽  
T. Mæhlum
Keyword(s):  
Heavy Metals ◽  
Aquatic Plants ◽  
Metal Uptake ◽  
High Capacity ◽  
Treatment Wetlands ◽  
The European Union ◽  
Toxic Heavy Metals ◽  
Limit Values ◽  
Fish Samples ◽  
Other Substances

A literature review shows that more than 500 compounds occur in wetlands, and also that wetlands are suitable for removing these compounds. There are, however, obvious pitfalls for treatment wetlands, the most important being the maintenance of the hydraulic capacity and the detention time. Treatment wetlands should have an adapted design to target specific compounds. Aquatic plants and soils are suitable for wastewater treatment with a high capacity of removing nutrients and other substances through uptake, sorption and microbiological degradation. The heavy metals Cd, Cu, Fe, Ni and Pb were found to exceed limit values. The studies revealed high values of phenol and SO4. No samples showed concentrations in sediments exceeding limit values, but fish samples showed concentrations of Hg exceeding the limit for fish sold in the European Union (EU). The main route of metal uptake in aquatic plants was through the roots in emergent and surface floating plants, whereas in submerged plants roots and leaves take part in removing heavy metals and nutrients. Submerged rooted plants have metal uptake potential from water as well as sediments, whereas rootless plants extracted metals rapidly only from water. Caution is needed about the use of SSF CWs (subsurface flow constructed wetlands) for the treatment of metal-contaminated industrial wastewater as metals are shifted to another environmental compartment, and stable redox conditions are required to ensure long-term efficiency. Mercury is one of the most toxic heavy metals and wetlands have been shown to be a source of methylmercury. Methyl Hg concentrations are typically approximately 15% of Hgt (total mercury). In wetlands polycyclic aromatic hydrocarbons (PAH), bisphenol A, BTEX, hydrocarbons including diesel range organics, glycol, dichlorodiphenyltrichloroethane (DDT), polychlorinated biphenyls (PCB), cyanide, benzene, chlorophenols and formaldehyde were found to exceed limit values. In sediments only PAH and PCB were found exceeding limit values. The pesticides found above limit values were atrazine, simazine, terbutylazine, metolachlor, mecoprop, endosulfan, chlorfenvinphos and diuron. There are few water quality limit values of these compounds, except for some well-known endocrine disrupters such as nonylphenol, phtalates, etc.

scholarly journals Content of heavy metals in Gentiana lutea L. roots and galenic forms

2007 ◽  
Vol 72 (2) ◽  
pp. 133-138 ◽  
Author(s):  
Dragoja Radanovic ◽  
Svetlana Antic-Mladenovic ◽  
Miodrag Jakovljevic ◽  
Mirjana Kresovic
Keyword(s):  
Heavy Metals ◽  
Quality Control ◽  
Soil Analysis ◽  
Root Tissue ◽  
Raw Material ◽  
Potential Hazard ◽  
Gentiana Lutea ◽  
Liquid Extract ◽  
Very High

An experimental field for the cultivated production of Gentiana lutea L. was established five years ago at the Suvobor Mountain, Serbia. Soil analysis of this area revealed the occurrence of high pseudo-total (Ni - 1270 mg/kg, Cr - 423 mg/kg, Co - 385 mg/kg) and available (especially Ni - 133 mg/kg) heavy metals contents in the soil. Hence, the aim of this research was to evaluate the quality of Gentiana lutea L. - roots and galenic forms (liquid extract in 70 % ethanol, spissum and siccum) produced from the roots, because, for most plants, heavy metals accumulate in the root tissue. The amounts of Ni and Cr found in the analyzed roots were very high (54 mg/kg and 14 mg/kg, respectively). The efficiency of ethanol in extracting heavy metals from the roots varied depending on the particular element. The highest efficiency was obtained for Ni (41.3 %), then for Cd (39.5 %), Pb (37.0%) and Co (30.4 %). According to this, a potential hazard exists for humans, if gentian's galenic forms are produced from the raw material with high heavy metals contents. It is concluded that quality control of the raw material must be carried out before further utilization of gentian. .

scholarly journals An Assessment of Metal Contamination Risk in Sediments of the Mohammad Abad River, Northern Iran

2021 ◽  
Vol 2 (8) ◽  
pp. 696-704
Author(s):  
Hassan Malvandi
Keyword(s):  
Heavy Metals ◽  
Biological Effects ◽  
Sediment Quality ◽  
Contamination Factor ◽  
Anthropogenic Source ◽  
Degree Of Contamination ◽  
Northern Iran ◽  
Pollution Levels ◽  
Quality Guidelines ◽  
Very High

Background: Sediments in the aquatic ecosystems can be used as suitable indicators for monitoring contaminants. Then, objectives of this study were to evaluate the concentration of heavy metals in the surface sediments of the Mohammad Abad River, to determine the degree of pollution of heavy metals in sediments using some major contamination indices; to identify the major sources (anthropogenic or natural sources) of the studied metals; and to evaluate the “reference river” of the river under study for ecotoxicology studies. Methods: Samples of sediment were taken from six sites of the river. The present study, eleven heavy metals (chromium, manganese, iron, cobalt, nickel, zinc, selenium, magnesium, silver, aluminum and arsenic) were studied. Results: Comparison of metal concentrations with those of Sediment Quality Guidelines (SQGs) showed no association with harmful biological effects for the heavy metals studied except for Se and As. The results of the contamination factor index showed low pollution levels for most metals (Cr, Mn, Fe, Co, Ni, Zn and Al), moderate pollution levels for As, and very high pollution levels for Se. The degree of contamination (Cd) and modified degree of contamination (mCd), showing the total contamination of elements, demonstrated very high degree contamination status in the study area. According to the index of quantification of contamination, the values of Cr, Mn, Fe, Ni, Zn and Al were derived mainly from geogenic sources of enrichment, while the values for Se and As were enriched by anthropogenic source of enrichment. Conclusion: These findings suggest that continuous monitoring of Se and As in sediment and organisms of the Mohammad Abad River should be directed to evaluate the threat of these elements to the public health and to the ecology of the river under study.

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