Genesis of Megacrystalline Uraninite: A Case Study of the Haita Area of the Western Margin of the Yangtze Block, China

Megacrystalline uraninite (up to one centimeter in size) represents one of the most important discoveries in uranium mineralogy in the western margin of the Yangtze Block and even in China in recent years. However, the genesis of megacrystalline uraninite remains controversial. In this study, the megacrystalline uraninite found in the felsic and quartz veins in the Haita area is examined for the first time. The study examined the geochemical characteristics of uraninite in the two veins and resulted in two primary findings. (1) The genesis of the uraninite was likely intrusive and was closely related to partial melting. (2) The quartz vein and feldspar vein are cogenetic and have a simple differentiation evolution relationship. Therefore, the partial melting of felsic materials during migmatization may be the most important mechanism of uranium mineralization in the study area. Furthermore, further simple fractional crystallization may be another important mechanism for the formation of megacrystalline uraninite. This study enriches the REE database of uraninite in uranium deposits worldwide, which is meaningful for studying the genesis of megacrystalline uraninite.

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Petrogenesis of contrasting magmatic suites in the Abu Kharif area, Northern Eastern Desert, Egypt: implications for Pan-African crustal evolution and tungsten mineralization

Geological Magazine ◽

10.1017/s0016756821001047 ◽

2021 ◽

pp. 1-27

Author(s):

Nora G Abdel Wanees ◽

Mohamed M El-Sayed ◽

Khalil I Khalil ◽

Hossam A Khamis

Keyword(s):

Partial Melting ◽

Fractional Crystallization ◽

Eastern Desert ◽

Granitic Magma ◽

Geochemical Data ◽

Calc Alkaline ◽

Quartz Veins ◽

Pan African ◽

Granite Suite ◽

Tungsten Mineralization

Abstract The Abu Kharif area in the Northern Eastern Desert consists of contrasting granitic magma suites: a Cryogenian granodiorite suite (850–635 Ma), an Ediacaran monzogranite suite (635–541 Ma) and a Cambrian alkali riebeckite granite suite (541–485 Ma). Tungsten mineralization occurs within W-bearing quartz veins and a disseminated type confined to the monzogranite. Whole-rock geochemical data classify the granodiorite as a late-orogenic I-type with calc-alkaline affinity, while the monzogranite and alkali riebeckite granite represent respectively a post-orogenic highly fractionated I-type with calc-alkaline affinity and an anorogenic A1-subtype with alkaline affinity. Geochemical modelling indicates that the three intrusions represent separate magmatic pulses where the granodiorite was generated by ∼75 % batch partial melting of an amphibolitic source followed by fractional crystallization of hornblende, biotite, apatite and titanite. The monzogranite was formed by 62 % batch partial melting of the normal ‘non-metasomatized’ Pan-African crust of calc-alkaline granite composition followed by fractional crystallization of plagioclase, biotite, K-feldspar, magnetite, ilmenite, with minor apatite and titanite. The alkali riebeckite granite was generated by 65 % batch partial melting of metasomatized Pan-African granite source followed by fractional crystallization of plagioclase, K-feldspar, amphibole and biotite with minor magnetite, apatite and titanite. In general, the parent magmas of the three intrusions were originally enriched in W, but with different concentrations. This W-enrichment would be caused by magmatic-related hydrothermal volatile-rich fluids and concentrated within the monzogranite.

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SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China

Minerals ◽

10.3390/min11040402 ◽

2021 ◽

Vol 11 (4) ◽

pp. 402

Author(s):

Guolin Guo ◽

Christophe Bonnetti ◽

Zhanshi Zhang ◽

Guanglai Li ◽

Zhaobin Yan ◽

...

Keyword(s):

Partial Melting ◽

Fractional Crystallization ◽

Secondary Ion Mass Spectrometry ◽

Uranium Mineralization ◽

Crustal Material ◽

Early Devonian ◽

The North ◽

Low Degree ◽

North Qinling ◽

The One

Pegmatite-type uranium mineralization occurs in the Shangdan domain of the North Qinling Orogenic Belt, representing a significant uraniferous province. The Guangshigou deposit is the largest U deposit of the district. Within the North Qinling area, a series of Caledonian granitic igneous rocks intruded the Proterozoic metamorphic rocks of the Qinling Group in two magmatic stages: (i) the Early Silurian Huichizi granite that was derived from a low degree of partial melting of thickened lower basaltic crust combined with mantle-derived materials following the subduction of the Shangdan Ocean; and (ii) the Late Silurian–Early Devonian Damaogou granite and associated pegmatites derived from the same source but emplaced in a late tectonic post-collisional extension environment. In the Guangshigou deposit, the U mineralization mainly occurs as uraninite disseminated in U-rich granitic biotite pegmatites, which formed by assimilation-fractional crystallization magmatic processes. Petrographic observations showed evidence for coeval crystallization of uraninite and other rock-forming minerals of the host pegmatite including quartz, feldspar, biotite, zircon, monazite, apatite, and xenotime. In addition, the low U/Th ratios (~19) and Th, REE, and Y enrichments characterized a magmatic origin for uraninite, which was likely derived from fractionated high-K calc-alkaline pegmatitic magma that experienced various degrees of crustal material contamination. In situ U-Pb isotopic dating performed by Secondary-Ion Mass Spectrometry (SIMS) on uraninite from the Guangshigou deposit yielded a crystallization age of 412 ± 3 Ma, which is concomitant (within errors) with the emplacement age of the host pegmatite (415 ± 2 Ma) and constrained the U ore genesis to the Early Devonian, which corresponds to the late Caledonian post-collisional extension in the North Qinling area. Uraninite then experienced various degrees of metamictization and/or post-Caledonian hydrothermal alteration characterized by an alteration rim associated with coffinite, chlorite and limonite. Finally, the characteristics of the pegmatite-related Guangshigou deposit exhibiting Th-rich uraninite which was the product of assimilation-fractional crystallization of pegmatitic magma defined a model significantly different than the one established for the world-class Rössing deposit characterized by Th-poor uraninite hosted in alaskite dykes formed by low degree of partial melting of U-rich metasediments.

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Islamic and Jewish Religious Feminists Tackle Islamic and Jewish Oral Law: Maintenance and Rebellion of Wives

Comparative Islamic Studies ◽

10.1558/cis.31497 ◽

2017 ◽

Vol 11 (1) ◽

pp. 35-63

Author(s):

Ruth Roded

Keyword(s):

State Policy ◽

Political System ◽

Daily Life ◽

The State ◽

The Political ◽

Jewish Law ◽

Modern Times ◽

Parallel Case ◽

First Time

Beginning in the early 1970s, Jewish and Muslim feminists, tackled “oral law”—Mishna and Talmud, in Judaism, and the parallel Hadith and Fiqh in Islam, and several analogous methodologies were devised. A parallel case study of maintenance and rebellion of wives —mezonoteha, moredet al ba?ala; nafaqa al-mar?a and nush?z—in classical Jewish and Islamic oral law demonstrates similarities in content and discourse. Differences between the two, however, were found in the application of oral law to daily life, as reflected in “responsa”—piskei halacha and fatwas. In modern times, as the state became more involved in regulating maintenance and disobedience, and Jewish law was backed for the first time in history by a state, state policy and implementation were influenced by the political system and socioeconomic circumstances of the country. Despite their similar origin in oral law, maintenance and rebellion have divergent relevance to modern Jews and Muslims.

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Erratum: Gravrok, J., et al. Beyond the Benefits of Assistance Dogs: Exploring Challenges Experienced by First-Time Handlers. Animals 2019, 9, 203

Animals ◽

10.3390/ani11010237 ◽

2021 ◽

Vol 11 (1) ◽

pp. 237

Author(s):

Jennifer Gravrok ◽

Dan Bendrups ◽

Tiffani Howell ◽

Pauleen Bennett

Keyword(s):

Assistance Dogs ◽

First Time

The authors wish to make the following corrections [1]:In Table 1, under case study 4, the code was originally labeled as H8, P8 and ADI 8; these labels should be H4, P4 and ADI 4, respectively [...]

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Investigating the Concerns of First-Time Distance Education Instructors

The International Review of Research in Open and Distributed Learning ◽

10.19173/irrodl.v20i5.4467 ◽

2019 ◽

Vol 20 (5) ◽

Cited By ~ 1

Author(s):

Halil Kayaduman ◽

Turgay Demirel

Keyword(s):

Distance Education ◽

Content Knowledge ◽

Stages Of Concern ◽

Concerns Based Adoption Model ◽

Descriptive Case Study ◽

Time Distance ◽

Adaptation Processes ◽

First Time ◽

Ongoing Concern

The purpose of the study is to investigate the concern developments of first-time distance education instructors using the concerns-based adoption model (CBAM). This study used stages of concern (SoC), a component of CBAM, as its theoretical framework. A descriptive case study was implemented, which focused on the adaptation processes of nine instructors lecturing for the first time via distance education. The instructors attended a two-day training, which was designed based on their initial concerns. Then instructors implemented their courses for four weeks via distance education. While the informational and personal stages (self-concerns) decreased compared to the initial findings, the consequence stage increased in intensity. However, self-concerns remained predominant in the process despite the reduction in self-concerns and increase in the consequence stage. Based on the findings, the implications for distance education and recommendations for addressing the instructors’ concerns are discussed. Recommendations for alleviating the concerns of first-time distance education instructors include: the provision of ongoing concern-based interventions that incorporate technological, pedagogical, and content knowledge; providing working examples related to distance education from which instructors can learn vicariously; and encouraging collaboration among instructors.

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Bearing Severity Fault Evaluation Using Contour Maps—Case Study

Applied Sciences ◽

10.3390/app11146452 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6452

Author(s):

César Ricardo Soto-Ocampo ◽

Juan David Cano-Moreno ◽

José Manuel Mera ◽

Joaquín Maroto

Keyword(s):

Health Indicators ◽

Bearing Faults ◽

Contour Maps ◽

Initial Stage ◽

Critical Components ◽

Bearing Damage ◽

First Time ◽

Current Operating

Increasing industrial competitiveness has led to an increased global interest in condition monitoring. In this sector, rotating machinery plays an important role, where the bearing is one of the most critical components. Many vibration-based signal treatments are already being used to identify features associated with bearing faults. The information embedded in such features are employed in the construction of health indicators, which allow for evaluation of the current operating status of the machine. In this work, the use of contour maps to represent the diagnosis map of a bearing, used as a health map, is presented for the first time. The results show that the proposed method is promising, allowing for the satisfactory detection and evaluation of the severity of bearing damage. In this initial stage of the research, our results suggest that this method can improve the classification of bearing faults and, therefore, optimise maintenance processes.

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Are seasonal lakes as productive as permanent lakes? A case study from Ireland

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f10-062 ◽

2010 ◽

Vol 67 (8) ◽

pp. 1291-1302 ◽

Cited By ~ 13

Author(s):

Helder Cunha Pereira ◽

Norman Allott ◽

Catherine Coxon

Keyword(s):

Seasonal Variation ◽

Linear Regression ◽

Chlorophyll A ◽

Algal Biomass ◽

P Limitation ◽

Underlying Causes ◽

Western Ireland ◽

Log Linear ◽

First Time

This paper compares, for the first time, nutrient levels and chlorophyll a measured in a set of seasonal lakes with those reported for permanent lakes in the literature. Twenty-two turloughs (karstic seasonal lakes) in western Ireland were sampled monthly from the onset of flooding (October) until they dried out (6 to 9 months). The turloughs showed similar levels of nutrients and chlorophyll a to those reported for Irish and international lakes. Chlorophyll a peaked between November and February in the majority of turloughs, sometimes with values higher than those measured in mesotrophic lakes in summer. A significant log-linear regression was found between total phosphorus and chlorophyll a, which suggests P limitation of algal biomass in the majority of the turloughs. The regression characteristics were not significantly different than those described in similar studies of permanent lakes. Patterns in seasonal variation of nutrients are also presented, their underlying causes being discussed in relation to their transport within catchments. Our results show that despite being predominantly winter phenomena, turloughs can be as productive as permanent lakes.

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Dispute Settlement of Diplomatic Relation Reviewed In International Law (Case Study of Spionageburning Australia on The President of Indonesia)

Activa Yuris: Jurnal Hukum ◽

10.25273/ay.v1i1.8655 ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Muhammad Iqbal Baiquni

Keyword(s):

International Relations ◽

International Law ◽

Dispute Settlement ◽

Code Of Conduct ◽

Qualitative Approach ◽

Legal Research ◽

Bilateral Relations ◽

Final Settlement ◽

First Time

<div><p class="abstract">The case of espionage or spying by Australia against Indonesia is not the first time, but there have been several attempts of espionage against Indonesia. This espionage act is an act of secretly collecting intelligence data in international relations in a country. In this paper, we discuss the wiretapping case and its resolution. This paper uses normative legal research with a qualitative approach. This paper examines the chronology of cases of tapping by Australia against Indonesia, wiretapping in human rights and international law, as well as the final settlement of tensions between Indonesia and Australia through an agreement on the Code of Conduct to normalize bilateral relations between the two countries.</p></div>

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ENVIRONMENTAL ISSUES OF SURFICIAL URANIUM DEPOSITS: OUM DHEROUA CASE STUDY (ISLAMIC REPUBLIC MAURITANIA)

10.32008/geolinks2021/b2/v3/10 ◽

2021 ◽

Author(s):

Mariia Kurylo ◽

Ivan Virshylo

Keyword(s):

Clean Energy ◽

Raw Material ◽

Open Pit ◽

Open Pit Mining ◽

Material Base ◽

Uranium Deposits ◽

Islamic Republic ◽

Natural Ecosystems ◽

Lower Estimation

Uranium deposits and resources are considered as an important raw material base for the implementation of scenarios for the green and clean energy transition. Traditionally discussed risks of potential environmental impacts of Uranium projects development could be subdivided by deposit type. Surficial type mineralization connected to the calcretes in shallow paleovalleys or playas has many specific features which might be analysed separately. Case study of Oum Dheroua Uranium project in the Islamic Republic of Mauritania shows an unexpected lower estimation of environmental risks comparatively to conventional Uranium projects despite to open-pit mining technology. The reasons for such estimation, connected to geographic location, the inclusion of Uranium minerals in natural ecosystems and low scale of deposits (both in grade and size sense). Potential by-products (Vanadium and Strontium) are not part of environmental factors assessment.

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Beneficial effect of lithium in female patient with bipolar affective illness and psoriasis

Pharmacotherapy in Psychiatry and Neurology ◽

10.33450/fpn.2021.05.002 ◽

2021 ◽

Vol 37 (2) ◽

Author(s):

Przemysław Filipiak ◽

Anna Jaskóła ◽

Karolina Gattner

Keyword(s):

Bipolar Disorder ◽

Case Report ◽

Beneficial Effect ◽

Female Patient ◽

Lithium Treatment ◽

The Other ◽

Patient Needs ◽

Affective Illness ◽

First Time

Objectives. Psoriasis makes a relative contraindication for lithium treatment which can exacerbate its symptoms or induce it itself. On the other hand, lithium exerts immuno-modulatory activity. Case study. In this paper, a case of a female patient is presented. The patient has been treated since 2012 for bipolar affective illness (bipolar disorder – BD) and psoriasis, which occurred for the first time during a depressive episode. Despite intensive pharmacological treatment, both as inpatient and outpatient, a satisfactory improvement of affective illness has not been obtained. After the introduction of lithium, a remission of BD was achieved as well as a reduction of psoriatic changes, which have been maintained until now (2021). Conclusion. The remission of Bipolar Disorder (BD) on lithium can suggest that the patient belongs to the group of the so-called excellent lithium responders. In the presented case remission of psoriasis was observed during lithium treatment. This case report must be treated with caution because remission could be spontaneous and the patient needs further observation.

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