Doctor of Philosophy

dissertationThe importance of flotation separation has long been, and continues to be, an important technology for the mining industry, especially to metallurgical engineers. However, the flotation process is quite complex and expensive, in addition to being influenced by many variables. Understanding the variables affecting flotation efficiency and how valuable minerals are lost to the tailings gives metallurgists an advantage in their attempts to increase efficiency by designing operations to target the areas of greatest potential value. A successful, accurate evaluation of lost minerals in the tailings and appropriate solutions to improve flotation efficiency can save millions of dollars in the effective utilization of our mineral resources. In this dissertation research, an attempt has been made to understand the reasons for the loss of valuable mineral particles in the tailings from Kennecott Utah Copper ores. Possibilities include liberation, particle aggregation (slime coating) and surface chemistry issues associated with the flotation separation. This research generally consisted of three main aspects. The first part involved laboratory flotation experiments and factors, which affect the flotation efficiency. Results of flotation testing are reported that several factors such as mineral exposure/liberation and slime coating and surface oxidation strongly affect the flotation efficiency. The second part of this dissertation research was to develop a rapid scan dual energy (DE) methodology using 2D radiography to identify, isolate, and prepare lost sulfide mineral particles with the advantages of simple sample preparation, short analysis time, statistically reliable accuracy and confident identification. The third part of this dissertation research was concerned with detailed characterization of lost particles including such factors as liberation, slime coating, and surface chemistry characteristics using advanced analytical techniques and instruments. Based on the results from characterization, the extent to which these factors contribute to the loss of sulfide mineral particles in the tailings were determined

Moğolistan sağlık sisteminin incelenmesi ve bir değerlendirme

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Sağlık sistemi, hedef nüfusun sağlık ihtiyaçlarını karşılamak için sağlık hizmeti sunan insan, kurum ve kaynakları kapsayan bir organizasyondur. Bir sağlık sisteminin değerlendirmesi için kullanlan temel göstergeler; yaşam beklentisi, doğurganlık oranı, anne ölüm hızı ve bebek ölüm hızı olarak sıralanabilir. Bu çalışmanın amacı, Moğolistan Sağlık Sisteminin incelenmesidir. Çalışma, mevcut durumun belirlenmesi, sağlık göstergelerinin değerlendirilmesi, orta gelir düzeyi altındaki ülkeler içindeki konumunun tespit edilmesi ve bazı ülkelerle karşılaştırılmasını içermektedir. Bir ülkenin mevcut sağlık sisteminin, toplum ihtiyaçlarına ne düzeyde cevap verdiği ve dünya gerçekleriyle ne oranda örtüştüğünün belirlenmesi; buna göre gerekli tedbirlerin alınması ve geliştirilmesi bu tür çalışmaları gerekli ve önemli kılmaktadır. Çalışmada, konuya ilişkin bilimsel yazın ve Dünya Bankası verilerinden yararlanılmıştır. Moğolistan sağlık göstergelerin değerlendirilmesi için En Küçük Kareler Yöntemi, orta gelir düzeyinin altında olan ülkelerinin sağlık göstergelerin değerlendirilmesi için ise Panel Veri Analizi (E-views 8 programı) kullanılmıştır. Elden edilen bulgulara göre Moğolistan, orta gelir düzeyi altındaki 51 ülke kategorisi içinde kişi başına düşen GSYİH açısından altıncı; kişi başına sağlık harcamaları bakımından 12. (onikinci); 1000 kişiye düşen hekim sayısı bakımından dördüncü; yatak sayısı bakımından ise ikinci sırada yeralmaktadır. Sağlık göstergeleri açısından ise, yaşam beklentisi bakımından 25. (yirmibeşinci); doğurganlık oranı açısından 31. (otuzbirinci) sıradadır. Anne ve bebek ölüm hızıları açısından ise 13. (onüçüncü) sıradadır. En Küçük Kareler Yöntemine göre yapılan hesaplamada, GSYİH içindeki sağlık harcamalarının bir birim artması halinde, yaş ortalamasının %7 artması; anne ölüm hızının %11 ve bebek ölüm hızının ise %7,9 oranında azalmasının mümkün olabileceği tahmin edilmiştir. Panel Veri Analizine göre yapılan hesaplamada ise, diğer sağlık sistemleri ile kıyaslandığında, Beveridge sağlık sisteminin yaşam beklentisini %7 oranında arttırabildiği; bebek ölüm oranını %64 ve anne ölüm oranını ise %106 azaltabildiği görülmüştür. Bu çalışmada elde edilen veriler ve ulaşılan bulgulara göre, Moğolistan ve orta gelir düzeyi altındaki ülkelerde, GSYİH içindeki sağlık harcamalarının arttırılması ve Beveridge sağlık sisteminin uygulanması durumunda, sağlık göstergelerinin olumlu yönde etkileneceği söylenebilir.Health system is an organization including people, institutions and resources that delivers health service for target population in order to satisfy their health needs. Basic indicators for evaluating health system are life expectancy, fertility rate, maternal mortality rate and infant mortality rate. This study aims to examine health system of Mongolia. In this context, current situation was identified, health indicators were assessed, country's status was determined among countries below the middle-income level and comparisons made with some of the countries. This study has provided significant policy implementation on health institutions and suggested how to encounter the health needs of the society. In this study, relevant scientific literature and World Bank data were utilized. "Least Squares Method" was implemented for assessing health indicators of Mongolia and "Panel Data Analysis" (8 programs for E-views) was utilized for assessing health indicators of countries below the middle-income level. According to the findings, Mongolia was ranked sixth by GDP per capita and twelfth by health expenditure per capita among 51 countries below the middle-income level. Fourth in terms of number of physicians per 1000 patients and second in terms of number of beds. According to the health indicators, it was ranked twenty fifth in the ranking among same countries by life expectancy and thirty first place by fertility rate. In terms of maternal and infant mortality rate it was ranked in thirteenth. In the calculations made according to the least squares method, if the health expenditures in GDP increases by one unit, the average age will increase by 7%. It was estimated that it would be feasible to reduce maternal mortality rate by 11% and infant mortality rate by 7.9%. According to the Panel Data Analysis, it was estimated that Beveridge health system can increase the life expectancy by 7% and reduce infant mortality by 64% and maternal mortality by 106%, compared to other health systems. The findings have revealed that there would be a positive impact on health indicators by increasing health expenditure in GDP and implementing Beveridge health system in Mongolia and in other countries below middle-income level

Low-Frequency Shear Parameters Viscoelastic Relaxation Process

An experimental study of the shear parameters of viscoelastic liquids is carried out by the acoustic resonance method based on the changes in the natural frequency and Q factor of a piezoelectric quartz resonator. The liquid to be studied is placed between a stationary quartz strap and the piezoelectric quartz crystal vibrating at the resonance frequency. For a set of drilling mud, the values of the real and imaginary shear module are obtained at a frequency of 74 kHz. The measurements are performed with a liquid layer thickness much smaller than the shear wavelength. It is shown that the shear modulus decreases with increasing strain amplitude. A hole-cluster model based on the Isakovich- Chaban nonlocal diffusion theory is proposed for explaining the low-frequency viscoelastic relaxation process.DOI: http://dx.doi.org/10.5564/pmas.v0i4.46 Proceedings of the Mongolian Academy of Sciences 2009 No 4 pp.53-5

Temperature Dependence of Shear Elasticity of Some Liquids

The temperature dependencies of real and imaginary parts of complex shear modulus of liquids have been obtained. It has shown that both real shear modulus G’ and ft imaginary shear modulus G” decrease with increasing temperature. The experiments have been carried out by resonance method at a shear oscillation frequency of 74 kHz. Liquids of viscosity 0.02 - 0.03 Pa-s have been investigated.DOI: http://dx.doi.org/10.5564/pmas.v0i4.47 Proceedings of the Mongolian Academy of Sciences 2009 No 4 pp.59-6

Disruption and pseudoautosomal localization of the major histocompatibility complex in monotremes

The characterization and chromosomal mapping of major histocompatibility complex (MHC)-containing BAC clones from platypus and the short-beaked echidna reveals new insights into the evolution of both the mammalian MHC and monotreme sex chromosomes

GPR measurements to assess the Emeelt active fault's characteristics in a highly smooth topographic context, Mongolia

International audienceTo estimate the seismic hazard, the geometry (dip, length and orientation) and the dynamics (type of displacements and amplitude) of the faults in the area of interest need to be understood. In this paper, in addition to geomorphologic observations, we present the results of two ground penetrating radar (GPR) campaigns conducted in 2010 and 2011 along the Emeelt fault in the vicinity of Ulaanbaatar, capital of Mongolia, located in an intracontinental region with low deformation rate that induces long recurrence time between large earthquakes. As the geomorphology induced by the fault activity has been highly smoothed by erosion processes since the last event, the fault location and geometry is difficult to determine precisely. However, by using GPR first, a non-destructive and fast investigation, the fault and the sedimentary deposits near the surface can be characterized and the results can be used for the choice of trench location. GPR was performed with a 50 MHz antenna over 2-D lines and with a 500 MHz antenna for pseudo-3-D surveys. The 500 MHz GPR profiles show a good consistency with the trench observations, dug next to the pseudo-3-D surveys. The 3-D 500 MHz GPR imaging of a palaeochannel crossed by the fault allowed us to estimate its lateral displacement to be about 2 m. This is consistent with a right lateral strike-slip displacement induced by an earthquake around magnitude 7 or several around magnitude 6. The 2-D 50 MHz profiles, recorded perpendicular to the fault, show a strong reflection dipping to the NE, which corresponds to the fault plane. Those profiles provided complementary information on the fault such as its location at shallow depth, its dip angle (from 23 • to 35 •) and define its lateral extension. Central Asia is known for its high level of seismic hazards, especially Mongolia, which has been one of the most seismically active intracontinental regions in the world with four large earthquakes (magnitude around 8) along its active faults in the western part of the country during the last century (Khilko et al. 1985). The deformation in Mongolia is located between compressive structures related to the collision and penetration of the Indian plate into the Eurasian plate and extensive structures in the north of the country related with the Baykal rift (Tapponnier & Molnar 1979; Baljinnyam et al. 1993; Schlupp 1996; Bayasgalan & Jackson 1999). The seismic activity observed in the vicinity of Ulaanbaatar (UB), capital of Mongolia, is relatively low compared to the activity observed in western Mongolia. Nevertheless, since 2005, the seismic activity around UB not only has increased, but is also organized (see Fig. 1) at the west of UB along two perpendicular directions, which determine two active faults: Emeelt fault, discovered in 2008 (NNW-SSE direction, 25-km-long minimum and situated about 10 km W of UB) and Hustai fault (WSW–ENE direction, 80 km long, with its NE tip at less than 20 km west of UB); their length and morphology indicate that they can produce earthquakes of magnitude 6.5–7.5 (Schlupp et al. 2012). Most of the Mongolian population (1.2 million over 3 million) is concentrated at UB, which is the main political and economical centre of the country. Hence, the study of seismic hazard and the estimation of the probability of future destructive earthquakes are of primary importance for the country (Dugarmaa et al. 2006). Since the last large earthquake, the faults geomorphology has been highly smoothed by erosional processes and the exact location of the fault plane surface rupture is thus hidden within a several metre wide strip. The GPR method has been proven to give good and useful results to characterize faults by identifying offsets of radar reflections (Malik et al. 2007; Christie et al. 2009; Yalçiner et al. 2013) an

Preparation of catalyst from natural montmorillonite mineral and its application in the synthesis of carbon nanosphere

In developed countries, nanoparticles derived from natural minerals and high-purity chemicals both are widely studied, while in developing countries like Mongolia, the natural minerals-based nanoparticles have more interest because of the low production cost and applicability of domestic natural minerals for their production. For the synthesis of natural mineral-based nanomaterials, it is important first to define the chemical composition and physical structure of local minerals and their possible processing route. We employed an environmentally friendly alkaline leaching procedure to recover silica from the clay mineral at 90°C for 24 hours. We applied an organic surfactant (CTAB) and a simple coprecipitation approach to form iron-doped silica nanoparticles. Consequently, we used iron-doped silica nanoparticles as a substrate and catalyst for the synthesis of carbon nanosphere at 750 °C for 1 hour in an argon and acetylene gas atmosphere. As a result, vast quantities of superhydrophobic carbon nanospheres (CNS) were obtained. The physicochemical properties of nanosilica substrate, non-functionalized carbon nanosphere, and functionalized carbon nanosphere (CNS) samples were characterized using XRD, XRF, SEM, EDS, TEM, and FTIR spectrometer. Iron-doped mineral-derived nanosilica particles demonstrated high catalytic efficiency and the potential to produce a large amount of value-added carbon nanospheres. Superhydrophobic CNS can be used in a variety of applications, particularly drug delivery; however, to use CNS in both aqueous and non-aqueous media, the superhydrophobic properties of CNS can be modified using different oxidizers. The changes in hydrophobicity of the CNS were examined and suggested possible oxidizing agents

Characterization of Alkali Activated Materials Prepared from Continuous Attrition and Ball Milled Fly Ashes

Mechanical activation is known to greatly influence the reactivity of fly ashes. In this paper, we report a comparative study of the properties of alkali-activated geopolymer materials prepared using both ball-milled and attrition-milled fly ashes. Ball milling was carried out for 30 min and 60 min while attrition milling was carried out continuously in a high-speed attritor. The surface area of the raw fly ash decreased from 4017 cm2/g to 3999 cm2/g and 3912 cm2/g after ball milling for 30 min and 60 min, respectively. By contrast, the surface area of the continuously attrition-milled fly ash increased to 5545 cm2/g. Fly ash processed by continuous attrition milling showed a 50% particle size reduction to 25–38 μm, whereas fly ash ball-milled for 30 and 60 min was reduced in size by 33.4 and 42.9%. The milled fly ash samples were activated with 8 M NaOH solution and cured at 40 °C for 68 h. After curing, the samples were maintained at room temperature, and their 7-, 14-, and 28-day compressive strengths were measured. The compressive strength of the attrition-milled 28-day geopolymer paste was 24.6 MPa; that of the geopolymers ball-milled for 30 and 60 min was 23.37 MPa and 17.58 MPa, respectively; and that of the unmilled control geopolymer fly-ash-based paste was 17 MPa. The improvement in the mechanical properties is attributed to the increased gel formation resulting from the increased surface area (decreased particle size) in the fly ash glass starting material

The multiple sex chromosomes of platypus and echidna are not completely identical and several share homology with the avian Z.

BACKGROUND: Sex-determining systems have evolved independently in vertebrates. Placental mammals and marsupials have an XY system, birds have a ZW system. Reptiles and amphibians have different systems, including temperature-dependent sex determination, and XY and ZW systems that differ in origin from birds and placental mammals. Monotremes diverged early in mammalian evolution, just after the mammalian clade diverged from the sauropsid clade. Our previous studies showed that male platypus has five X and five Y chromosomes, no SRY, and DMRT1 on an X chromosome. In order to investigate monotreme sex chromosome evolution, we performed a comparative study of platypus and echidna by chromosome painting and comparative gene mapping. RESULTS: Chromosome painting reveals a meiotic chain of nine sex chromosomes in the male echidna and establishes their order in the chain. Two of those differ from those in the platypus, three of the platypus sex chromosomes differ from those of the echidna and the order of several chromosomes is rearranged. Comparative gene mapping shows that, in addition to bird autosome regions, regions of bird Z chromosomes are homologous to regions in four platypus X chromosomes, that is, X1, X2, X3, X5, and in chromosome Y1. CONCLUSION: Monotreme sex chromosomes are easiest to explain on the hypothesis that autosomes were added sequentially to the translocation chain, with the final additions after platypus and echidna divergence. Genome sequencing and contig anchoring show no homology yet between platypus and therian Xs; thus, monotremes have a unique XY sex chromosome system that shares some homology with the avian Z.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Monotreme glucagon-like peptide-1 in venom and gut: one gene – two very different functions

This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/The importance of Glucagon like peptide 1 (GLP-1) for metabolic control and insulin release sparked the evolution of genes mimicking GLP-1 action in venomous species (e.g. Exendin-4 in Heloderma suspectum (gila monster)). We discovered that platypus and echidna express a single GLP-1 peptide in both intestine and venom. Specific changes in GLP-1 of monotreme mammals result in resistance to DPP-4 cleavage which is also observed in the GLP-1 like Exendin-4 expressed in Heloderma venom. Remarkably we discovered that monotremes evolved an alternative mechanism to degrade GLP-1. We also show that monotreme GLP-1 stimulates insulin release in cultured rodent islets, but surprisingly shows low receptor affinity and bias toward Erk signaling. We propose that these changes in monotreme GLP-1 are the result of conflicting function of this peptide in metabolic control and venom. This evolutionary path is fundamentally different from the generally accepted idea that conflicting functions in a single gene favour duplication and diversification, as is the case for Exendin-4 in gila monster. This provides novel insight into the remarkably different metabolic control mechanism and venom function in monotremes and an unique example of how different selective pressures act upon a single gene in the absence of gene duplication