High-Density Ceramics Obtained By Andesite Basalt Sintering

Modern industrial requirements include not only the usage of constructive materials with good mechanical properties but also materials obtained through environmentally friendly and low-cost processing procedures. Basalt, as a low-cost raw material, is regarded as a good candidate for industrial constructive parts production. In the present study, andesite basalt originated from the deposit site "Donje Jarinje", Serbia, was examined as a potential raw material for high-density ceramics production. The production of high-density ceramics included dry milling, homogenization, cold isostatic pressing, and sintering in the air. To determine the optimal processing parameters the sintering was conducted at 1040, 1050, 1060, 1070, and 1080 °C, and afterward the sintering duration was varied from 30 to 240 min at the optimal sintering temperature of 1060 °C. Characterization of the starting and sintered materials included the estimation of particle size distribution, density, hardness, and fracture toughness complemented with X-ray diffraction, light optical microscopy, scanning electron microscopy, and energy dispersive spectroscopy analysis. Phase transformations did not occur during processing in the investigated temperature range from 1040 to 1080 °C. The obtained research results showed that 99.5% of relative density and the highest hardness and fracture toughness values of 6.7 GPa and 2.2 MPaÖm, respectively, were achieved for the andesite basalt sintered at 1060 °C for 60 min in the air. The results of the presented study confirmed that the sintered andesite basalt can be used as a high-density ceramic material for various industrial applications since this environmentally friendly material shows satisfactory mechanical properties.

Ảnh hưởng của đặc điểm thạch học, tướng - môi trường trầm tích đến chất lượng chứa của tập G, cấu tạo Lạc Đà Xanh, Lô 15-1/05, bể Cửu Long

Sự xuất hiện của các đá trầm tích tập G trong cấu tạo Lạc Đà Xanh (LDX), Lô 15-1/05, bể Cửu Long là phát hiện mới so với các nghiên cứu trước đây về địa chất, hệ thống dầu khí tại Lô 15-1/05. Các thành tạo tập G tạm thời được đặt tên hệ tầng Lạc Đà Vàng, bên dưới hệ tầng Lạc Đà Nâu (Tập E) và phủ lên trên các đá móng magma xâm nhập granitoid và các đá magma phun trào andesite - basalt có tuổi trước Đệ tam. Kết quả nghiên cứu về thạch học, mẫu lõi và địa vật lý giếng khoan của các giếng LDX-1X, LDX-2X và LDX-3X thuộc cấu tạo Lạc Đà Xanh cho thấy các đá trầm tích tập G bao gồm: cát kết xen kẹp bột kết, sét kết/đá phiến sét, được tích tụ trong hệ thống môi trường quạt bồi tích (alluvial fan), quạt tam giác châu (fan delta), sông (braided fluvial) và hồ (lacustrine). Chất lượng thấm chứa của đá trầm tích tập G kém, do bị ảnh hưởng bởi sự phát triển mạnh của các khoáng vật thứ sinh cùng với quá trình nén ép do chôn vùi sâu.

Influence of Type of Alkaline Activator on Durability of Alkali Activated Concrete Using Aggregates Capable to Alkali-Silica Reaction

The paper discloses results of durability studies of alkali activated concretes based on different alkali sources using aggregates capable to alkali-silica reaction (ASR). Active aggregates are representing by perlite, andesite, basalt and sandstone. It is shown that the alkali-reactive aggregates, in degree of their influence on expansion deformations occurring in the slag alkaline concretes may be placed in the following row: perlite< sand< sandstone< basalt< andesite, and a growth of expansion deformations is observed with increase in the active silica content in the aggregate. Also it is set that alkaline components, in degree of their influence on the rate of expansion deformations development in the slag alkaline concretes made with reactive aggregates, may be placed in the following sequence: Na2CO3<Na2O SiO2 < NaOH< Na2O 2SiO2.

A new approach to the problem of assessing the radon hazard of building sites

Radon and its daughter products create more than half dose from all natural radiation sources. The radon entering the buildings is emitted mainly from soils lying at the base of the foundation. Therefore, before carrying out construction work, the radon hazard of the construction area are determined. In the Russian Federation, the radon hazard of an area can be determined using radon flux density measured on the soil surface. To date, radon researchers came to the conclusion that the geology of the territory affects the amount of radon released from the soil surface. However, there are almost no studies devoted to the release of radon from the surface of various soil types. The paper presents the measuring results of the radon flux density on the surface of loess loams, porcelain clay, argillaceous slate, sand-and-gravel sediment, rocky limestone, clayey limestone, andesite-basalt porphyrite and quartzrock. The measurements were carried out by the accumulation chamber method using the Alfarad Plus measuring complex. Also, measuring radium activity concentration and soil moisture were carried out. The research demonstrates that, depending on the type of soil, the amount of radon emanating from its surface differs by more than an order of magnitude. The largest values of radon flux density of ~ 800 mBq∙m-2s-1 were recorded for andesite-basalt porphyrite and quartzrock. The smallest ones of ~ 40 mBq∙m-2s-1 were registered for loess loams and argillaceous slates. For soils consisting of small sand and clay grains, a rather strong dependence of the radon flux density on soil moisture was found. When measuring soils with low moisture (2-6%), a proportional dependence of the radium activity concentration on the amount of radon emanating from the soil surface is not observed. The types of soils that lie at the foundations of the buildings, and their physical properties can be used as the basis for classifying building sites according to the degree of radon hazard. Relevant information may be provided by organizations engaged in design and survey work at building plots. The approach proposed in the work for assessing radon hazard will allow avoiding labor-intensive measurements of radon and thereby reduce the financial, material and labor costs of building construction.

Geology and Petrology of Omzha Block, Zhob Ophiolite, northern Balochistan, Pakistan

The Zhob Ophiolite is divided into three detached blocks including the Omzha block. The Omzha block is mapped and divided into lithological units such as ultramafic rock, mafic-felsic rock, and volcanic–volcaniclastic–pelagic rocks. These units are quite deformed and mixed up and are associated with one another by thrust faults. Petrography and geochemistry divide them into gabbro, diorite, plagiogranite, pheno-tephrite and trachy-andesite basalt, trachy basalt, chert, limestone, and mudstone. The ultramafic rocks are dominantly serpentinized harzburgite, dunite, and a minor lherzolite. Petrography of peridotite shows that it may be depleted in nature and may have residual after processes such as partial melting and the melt-rock reaction of a lherzolitic source. The gabbroic rocks are less well-developed and highly deformed. They are cross-cut by diorite, plagiogranite and anorthosite’ intrusions. The gabbro may be the plutonic section of Omzha block’ crust while the intermediate-felsic igneous rocks may have formed by the anataxis of crustal gabbro. The volcanic–volcaniclastic–pelagic rocks unit may be corrected with Bagh complex found underneath the Muslim Bagh Ophiolite. The metamorphic sole rocks of Omzha block are highly deformed and dismembered are comprising of metamorphic facies such as amphibolite, quartz-mica schist, and greenschist.

Good Mining Practice Sebagai Penopang Pengelolaan Pertambangan Berkelanjutan Dan Berwawasan Lingkungan

Garut Regency is a district that has enough of the potential mineral resources, such metallic minerals and nonmetals including sand and andesite, one of the areas is Mount Guntur. Many factors encourage to stop mining activity, one of them is environmental factors. Therefore, it needs a relocation to other areas, by consideration of the potential mineral deposits, to fulfill the increasing market demand. The relocation is done as a step that mining activities do not interfere with mountain tourism, natural environmental conditions, and policies related to the environment, safety and occupational health and spatial planning. The field observations result, study geological location dominated by Qhg, Qypu, and QYM. The other geological aspects that must be considered is the distribution pattern of the river. The vegetation conditions results show that the types of vegetation found in many locations namely crops and plantations, shrubs and bamboo. Based on the calculation of immeasurable resources, there is Boulder andesite-basalt amounted to 13,515,740 MT, with an estimated average thickness taken from the surface to the deepest point of 60 meters penetration geolistrik, although in fact the thickness of andesite - basalt is absence of definite size, thereby the concretion Factor has a value of 30%.

Distribution mapping of metal sediment using polarization data interpretation on the field “X” in PT Newmont Nusa Tenggara (PT NNT)

<span>Geophysical research has been done on mapping distribution of metal deposits in the field "X" PT <span>Newmont Nusa Tenggara using induced polarization geoelectric method pole-dipole <span>configuration. Measurements performed using IRIS intrument type Elrec Pro where measurements <span>of seven lines with length 2.3 km and electrode spacing 100 m. Induced polarization data further<br /><span>analyzed by using Res2dinv version 3.56 and Surfer 10. Interpreted based on the parameters of <span>chrageability and resistivity that correlated with regional geological information from the study <span>area. As a result, the structure of rocks beneath the surface lithology research area consists of five <span>units major rock that is tuffan claystone unit, sandstone tuffan unit, limestone unit, lava-breccia<br /><span>unit, and andesite-basalt unit. Mineralization zone at the high chargeabilitas at 69.7 to 155 msec <span>range supported by the low resistivity in the range of 4.21 to 26.5 Ωm which straight of anomalies <span>in West-East direction at the depth of ± 50-400 m.</span></span></span></span></span></span></span></span></span></span><br /></span>