Aqueous systems at high temperature. Solubility to 200.degree. of calcium sulfate and its hydrates in sea water and saline water concentrates, and temperature-concentration limits

1968 ◽  
Vol 13 (1) ◽  
pp. 83-93 ◽  
Author(s):  
William L. Marshall ◽  
Ruth. Slusher
Alloy Digest ◽  
1995 ◽  
Vol 44 (4) ◽  

Abstract VLX 954 is an austenitic stainless steel with 6% (nominal) molybdenum. The alloy is particularly resistant to localized corrosion in sea water and chloride environments. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-589. Producer or source: DMV Stainless USA Inc.


2012 ◽  
Vol 16 (7) ◽  
pp. 1845-1862 ◽  
Author(s):  
F. Jørgensen ◽  
W. Scheer ◽  
S. Thomsen ◽  
T. O. Sonnenborg ◽  
K. Hinsby ◽  
...  

Abstract. Geophysical techniques are increasingly being used as tools for characterising the subsurface, and they are generally required to develop subsurface models that properly delineate the distribution of aquifers and aquitards, salt/freshwater interfaces, and geological structures that affect groundwater flow. In a study area covering 730 km2 across the border between Germany and Denmark, a combination of an airborne electromagnetic survey (performed with the SkyTEM system), a high-resolution seismic survey and borehole logging has been used in an integrated mapping of important geological, physical and chemical features of the subsurface. The spacing between flight lines is 200–250 m which gives a total of about 3200 line km. About 38 km of seismic lines have been collected. Faults bordering a graben structure, buried tunnel valleys, glaciotectonic thrust complexes, marine clay units, and sand aquifers are all examples of geological structures mapped by the geophysical data that control groundwater flow and to some extent hydrochemistry. Additionally, the data provide an excellent picture of the salinity distribution in the area and thus provide important information on the salt/freshwater boundary and the chemical status of groundwater. Although the westernmost part of the study area along the North Sea coast is saturated with saline water and the TEM data therefore are strongly influenced by the increased electrical conductivity there, buried valleys and other geological elements are still revealed. The mapped salinity distribution indicates preferential flow paths through and along specific geological structures within the area. The effects of a future sea level rise on the groundwater system and groundwater chemistry are discussed with special emphasis on the importance of knowing the existence, distribution and geometry of the mapped geological elements, and their control on the groundwater salinity distribution is assessed.


1977 ◽  
Vol 66 (1) ◽  
pp. 97-110
Author(s):  
T. J. Bradley ◽  
J. E. Phillips

1. The drinking rate of the saline-water mosquito larva Aedes taeniorhyncus (100 nl.mg-1.h-1) is unaffected by the salinity of the external medium, but is directly proportional to the surface area of the animal. 2. Haemolymph Na+, Mg2+, K+, Cl-, SO42- and osmotic concentrations were measured in larvae adapted to 10%, 100% and 200% seawater and were found to be regulated within a narrow range. 3. With the exception of potassium, ionic concentrations in rectal secretion were found to increase with increasing concentrations of the sea water in which larvae were reared. 4. The osmotic concentration of rectal secretion was unaffected by changes in haemolymph osmotic concentration but did rise when sodium or chloride concentrations of the haemolymph were increased. High levels of these ions also stimulated the rate of fluid secretion. 5. Transport of chloride and sodium by the rectum exhibits the kinetics of allosteric rather than classical enzymes.


1997 ◽  
Vol 127 (3) ◽  
pp. 292-299 ◽  
Author(s):  
Yukiko Hanzawa ◽  
Daisuke Hiroishi ◽  
Chihiro Matsuura ◽  
Kenkichi Ishigure ◽  
Masashi Nagao ◽  
...  

2018 ◽  
Vol 64 (4) ◽  
pp. 407-426
Author(s):  
N. V. Kubyshkin ◽  
I. V. Buzin ◽  
N. V. Golovin ◽  
Yu. P. Gudoshnikov ◽  
G. A. Zamarin ◽  
...  

Starting from the mid 2000-s the increase of sustained development of the Russian Arctic is observed, in many cases the technologies using the ice cover as an infrastructure element and the ice as the construction materials are used. In the present time the different approaches of use of natural and artificial ice for applied tasks on the Arctic offshore exist. For example, the clearance of the upper surface of ice from snow and ridges is used for the purposes of the vessel unloading on the fast ice or constructing the airstrips on the drifting ice cover. In case of insufficient thickness of the level ice the latter is increased by the means of preliminary freezing (natural on the bottom side of ice and artificial by pouring the fresh or saline water on the upper surface). By constructing the artificial ice islands the ice body is made by spraying the sea water with the partial freezing of the water drops in the air and further freezing of the 2-phase elements (i.e. ice crystals in the liquid film) on the surface of the ice cover. The problem of cracks in the ice cover is solved by different means according to the proper task. When it is possible, the cracks are “healed”— i.e. are filled with the snow and ice gravel and then freezed. In case of impossibility of use of such method (for example — presence of tidal cracks or relatively high air temperature) the cracks are overlapped with the help of different covers made of different materials and of different sizes. The promising trend of ice technology is involving the reinforced or composite ice, having the increased strength, into the ice engineering practice. By unloading the cargo ships on the fast ice the ice strength is decreased locally for the purpose of easy berthing of the vessel with safekeeping the original strength of the surrounding ice for the aims of the vessel unloading. This problem is solved by creating the system of notches in the ice cover according to the vessel dimensions. The specialized hydrometeorological support on every stage of the ice engineering operation is an essential element of the ice engineering activities on the ice cover of lakes, rivers and seas.


2002 ◽  
Vol 3 (1) ◽  
pp. 5 ◽  
Author(s):  
V. ZERVAKIS ◽  
D. GEORGOPOULOS

The combination of two research projects offered us the opportunity to perform a comprehensive study of the seasonal evolution of the hydrological structure and the circulation of the North Aegean Sea, at the northern extremes of the eastern Mediterranean. The combination of brackish water inflow from the Dardanelles and the sea-bottom relief dictate the significant differences between the North and South Aegean water columns. The relatively warm and highly saline South Aegean waters enter the North Aegean through the dominant cyclonic circulation of the basin. In the North Aegean, three layers of distinct water masses of very different properties are observed: The 20-50 m thick surface layer is occupied mainly by Black Sea Water, modified on its way through the Bosphorus, the Sea of Marmara and the Dardanelles. Below the surface layer there is warm and highly saline water originating in the South Aegean and the Levantine, extending down to 350-400 m depth. Below this layer, the deeper-than-400 m basins of the North Aegean contain locally formed, very dense water with different θ /S characteristics at each subbasin. The circulation is characterised by a series of permanent, semi-permanent and transient mesoscale features, overlaid on the general slow cyclonic circulation of the Aegean. The mesoscale activity, while not necessarily important in enhancing isopycnal mixing in the region, in combination with the very high stratification of the upper layers, however, increases the residence time of the water of the upper layers in the general area of the North Aegean. As a result, water having out-flowed from the Black Sea in the winter, forms a separate distinct layer in the region in spring (lying between “younger” BSW and the Levantine origin water), and is still traceable in the water column in late summer.


2016 ◽  
Vol 5 (3) ◽  
pp. 505 ◽  
Author(s):  
Rachmansyah Rachmansyah ◽  
Akhmad Mustafa ◽  
Mudian Paena

Kota Pekalongan memiliki lahan tambak yang produktivitas tambaknya masih tergolong relatif rendah. Oleh karena itu, dilakukan penelitian untuk mengetahui karakteristik lahan dalam upaya menentukan kesesuaian dan pengelolaan lahan untuk budidaya tambak demi peningkatan produktivitas tambak di Kota Pekalongan. Faktor yang dipertimbangkan dalam mengetahui karakteristik lahan adalah: tanah, topografi, hidrologi, vegetasi, dan iklim. Analisis spasial dalam Sistem Informasi Geografis digunakan dalam penentuan kesesuaian lahan untuk budidaya tambak. Pengelolaan lahan ditentukan berdasarkan karakteristik lahan yang disesuaikan dengan teknologi dan komoditas yang dapat diaplikasikan di tambak. Tanah tambak di Kota Pekalongan tergolong tanah aluvial non-sulfat masam yang tidak memiliki potensi kemasaman tanah yang tinggi dan sebagian kecil tanah sulfat masam. Sumber air laut untuk tambak tergolong agak keruh dan salinitas air tambak cukup bervariasi sebagai akibat adanya sumber air tawar yang berasal dari Sungai Pekalongan dan sodetan. Vegetasi bakau adalah jenis vegetasi yang dominan di kawasan tambak sebab adanya Program GERHAN (Gerakan Nasional Rehabilitasi Hutan dan Lahan) di Kota Pekalongan. Curah hujan di Kota Pekalongan sebesar 2.300 mm/tahun di mana curah hujan yang rendah dijumpai pada bulan Juli sampai Oktober. Di kawasan pesisir Kota Pekalongan dijumpai tambak, sawah, sawah terintrusi, dan pemukiman yang luasnya masing-masing 332,29; 372,53; 183,83; dan 619,73 ha. Dari luas tambak yang ada di Kota Pekalongan, yaitu 331,292 ha ternyata tidak ada tambak yang tergolong sangat sesuai (kelas S1), 191,856 ha tergolong cukup sesuai (kelas S2) dan 140,436 ha tergolong kurang sesuai (kelas S3). Pada areal yang mengandung unsur atau senyawa penyebab kemasaman yang tinggi disarankan untuk melakukan upaya perbaikan tanah terlebih dahulu berupa remediasi, pemberian pupuk yang mengandung nitrogen pada areal yang memiliki rasio C:N tanah yang tinggi serta pemberian pupuk kandang pada tanah yang mengandung liat lebih besar 60% dan bahan organik kurang dari 8%.Pekalongan City has brackishwater ponds with low productivity. Hence, a survey was conducted to know land characteristics as an effort to determine land suitability and land management to increase the productivity of brackishwater ponds in Pekalongan City, Central Java Province. Factors considered to determine the characteristics of land were soil, topography, hydrology, vegetation, and climate. Spatial analysis in Geographical Information System was used to determine land suitability for brackishwater ponds. Land management was determined based on the characteristics of land conditioned to the types of technology and commodity applied in the brackishwater ponds. Soil of brackishwater ponds in Pekalongan City was dominated by alluvial non-acid sulfate soil in large areas and acid sulfate soil in small areas. Source of sea water for brackishwater ponds has high turbidity and high variation of salinity due to presence of freshwater supply from Pekalongan River and man made canals. Mangrove vegetation is dominant in the coastal area of Pekalongan City, because the presence of GERHAN (National Action for Forest and Land Rehabilitation) Program. The average of rainfall in Pekalongan City is 2,230 mm/year, where low of rainfall occurrs in July until October. The result revealed that the coastal area of Pekalongan City had brackishwater ponds, paddy field, paddy field intruded saline water and settlement of 332.29 ha; 372.53 ha; 183.83ha; and 619.73 ha, respectively. From the total brackishwater ponds in Pekalongan City i.e. 331.292 ha, there were no brackishwater ponds classified as highly suitable (S1 class), but it was found moderately suitable or S2 class (191.856 ha) and marginally suitable or S3 class (140,436 ha). It is suggested to conduct improving soil quality first, including remediation of the areas that contain elements or compounds causing the high acidity of soil, fertilizing with fertilizer containing nitrogen in the areas that have high C:N ratio and applying manure in the soils that contain clay more than 60% and organic matter less than 8%. 


2011 ◽  
Vol 13 (3-4) ◽  
pp. 149
Author(s):  
Georgij I. Ksandopulo

Potential economic possibility of using centrifugal force for production of noble ferroalloys is shown. Connected with this process, the limits of stable combustion are conditioned by formation of adiabatic regime of combustion due to the effect of acceleration of the combustion front by centrifuged particles of melted metal product. There appears the possibility to create a continuous technology of production of ferroalloys on the basis of aluminothermy and of significantly decreased low limit concentration of the sought for metal in the initial row material.


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