New Insights Into Recovery of Copper and Gold from Old Flotation Tailings from Bor, Serbia

Mining and processing tailings often contain significant amounts of valuable metals, that can represent valuable sources of secondary raw materials. Especially this is case in early-stage operations, in which the head grades were higher, and the tailings were higher grade. These tailings can also present a substantial risk to the environment. Serbia has copper deposits which have been exploited since ancient times, and these operations have generated large amounts of mineral processing tailings. The main objective of this study is to show how valuables can be recovered from chemically and mineralogically challenging tailings. After detailed chemical and mineralogical characterization, the laboratory scale flotation tests focused on evaluating the effect of particle size, different types of collectors, pH, and pulp potential. Based on the test work, copper and gold can be recovered effectively into pyrite concentrate

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Post-Tonsillectomy Hemorrhage Diagnosis and Management

Otolaryngology ◽

10.1016/j.otohns.2008.05.113 ◽

2008 ◽

Vol 139 (2_suppl) ◽

pp. P34-P35 ◽

Cited By ~ 2

Author(s):

Michael S Morris

Keyword(s):

Ct Angiography ◽

Early Stage ◽

Cardiopulmonary Arrest ◽

Vascular Trauma ◽

Post Mortem ◽

Direct Examination ◽

Operative Field ◽

Different Types ◽

Vascular Physiology ◽

Vascular Spasm

Objective 1) Better recognize pathophysiology of postoperative tonsillectomy hemorrhage. 2) Be able to better differentiate the different types of post-tonsillectomy hemorrhage based upon understanding the vascular physiology and adjust management accordingly. Methods Post-tonsillectomy complications in children and adults were reviewed. 7 cases of hemorrhage, including 5 deaths, were carefully reviewed. Patients ranged between 2–40 years of age. This represents the largest series of post-tonsillectomy deaths reported to date. All postoperative deaths were due to bleeding and cardiopulmonary arrest. Post-mortem analysis was undertaken on those patients. CT angiography was reviewed in one surviving patient and the utility of this type of scanning is discussed. Results Post-tonsillectomy bleeding is one of the most worrisome otolaryngology concerns. Patients with bleeding on postoperative days 2–3 reported episodic bleeding stopping spontaneously. In these patients, the episode of unobserved bleeding signaled a vascular spasm with a likehood of recurrence. When the bleeding recurred it was massive and occured in a uncontrolled setting, leading to a poor outcome. Vascular trauma and spasm is likely. Conclusions Postoperative tonsillectomy bleeding is better managed by differentiating those patients with early stage bleeding on postoperative days 2–3. Direct examination of the operative field is imperative. Ancillary testing including CT angiograpy is helpful in the evaluation.

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PU composites based on different types of textile fibers

Journal of Composite Materials ◽

10.1177/00219983211031656 ◽

2021 ◽

pp. 002199832110316

Author(s):

Nuno Gama ◽

B Godinho ◽

Ana Barros-Timmons ◽

Artur Ferreira

Keyword(s):

Thermal Conductivity ◽

Raw Materials ◽

Natural Fibers ◽

Tensile Modulus ◽

High Water ◽

Textile Fibers ◽

Synthetic Fibers ◽

Hydrophilic Nature ◽

Different Types ◽

Recycled Composites

In this study polyurethane (PU) residues were mixed with residues of textile fibers (cotton, wool and synthetic fibers up to 70 wt/wt) to produce 100% recycled composites. In addition, the effect of the type of fiber on the performance of the ensuing composites was evaluated. The presence of fibers showed similar effect on the density, reducing the density in the 5.5-9.0% range. In a similar manner, the addition of fillers decreased their thermal conductivity. The 70 wt/wt wool composite presented 38.1% lower thermal conductivity when compared to the neat matrix, a reduction that was similar for the other type of fibers. Moreover, the presence of fillers yields stiffer materials, especially in the case of the Wool based composites, which with 70 wt/wt of filler content increased the tensile modulus of the ensuing material 3.4 times. This was attributed to the aspect ratio and stiffness of this type of fiber. Finally, the high-water absorption and lower thermal stability observed, especially in the case of the natural fibers, was associated with the hydrophilic nature of fibers and porosity of composites. Overall, the results suggest that these textile-based composites are suitable for construction and automotive applications, with the advantage of being produced from 100% recycled raw-materials, without compromised performance.

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Modified Nanoclays/Straw Fillers as Functional Additives of Natural Rubber Biocomposites

Polymers ◽

10.3390/polym13050799 ◽

2021 ◽

Vol 13 (5) ◽

pp. 799

Author(s):

Justyna Miedzianowska ◽

Marcin Masłowski ◽

Przemysław Rybiński ◽

Krzysztof Strzelec

Keyword(s):

Natural Rubber ◽

Raw Materials ◽

Research Work ◽

Damping Properties ◽

Main Research ◽

Functional Additives ◽

Different Types ◽

Elastomeric Materials ◽

Research Goal ◽

The Impact

Increasingly, raw materials of natural origin are used as fillers in polymer composites. Such biocomposites have satisfactory properties. To ensure above-average functional properties, modifications of biofillers with other materials are also used. The presented research work aimed to produce and characterize elastomeric materials with a straw-based filler and four different types of montmorillonite. The main research goal was to obtain improved functional parameters of vulcanizates based on natural rubber. A series of composites filled with straw and certain types of modified and unmodified nano-clays in various ratios and amounts were prepared. Then, they were subjected to a series of tests to assess the impact of the hybrids used on the final product. It has been shown that the addition of optimal amounts of biofillers can, inter alia, increase the tensile strength of the composite, improve damping properties, extend the burning time of the material and affect the course of vulcanization or cross-linking density.

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Mineralogical Characterization and Firing Temperature Delineation on Minoan Pottery, Focusing on the Application of Micro-Raman Spectroscopy

Heritage ◽

10.3390/heritage2030163 ◽

2019 ◽

Vol 2 (3) ◽

pp. 2652-2664 ◽

Cited By ~ 2

Author(s):

E. Grammatikakis ◽

Kyriakidis ◽

D. Demadis ◽

Cabeza Diaz ◽

Leon-Reina

Keyword(s):

Bronze Age ◽

Firing Temperature ◽

Raw Materials ◽

Morphological Characteristics ◽

Ceramic Technology ◽

Phase Identification ◽

Mineralogical Characterization ◽

Analytical Protocol ◽

Crucial Information ◽

Analytical Tools

Ceramic objects in whole or in fragments usually account for the majority of findings in an archaeological excavation. Thus, through examination of the values these items bear, it is possible to extract important information regarding raw materials provenance and ceramic technology. For this purpose, either traditional examination protocols could be followed, focusing on the macroscopic/morphological characteristics of the ancient object, or more sophisticated physicochemical techniques are employed. Nevertheless, there are cases where, due to the uniqueness and the significance of an object of archaeological value, sampling is impossible. Then, the available analytical tools are extremely limited, especially when molecular information and mineral phase identification is required. In this context, the results acquired from a multiphase clay ceramic dated on Early Neopalatioal period ΜΜΙΙΙΑLMIA (1750 B.C.E.–1490 B.C.E.), from the Minoan Bronze Age site at Philioremos (Crete, Greece) through the application of Raman confocal spectroscopy, a nondestructive/ noninvasive method are reported. The spectroscopic results are confirmed through the application of Xray microdiffraction and scanning electron microscopy coupled with energy dispersive Xray spectrometry. Moreover, it is demonstrated how it is made possible through the application of microRaman (μRaman) spectroscopy to examine and collect crucial information from very small inclusions in the ceramic fabric. The aim of this approach is to develop an analytical protocol based on μRaman spectroscopy, for extracting firing temperature information from other ceramic finds (figurines) where due to their uniqueness sampling and analyses through other techniques is not possible. This information can lead to dating but also to firing kiln technology extrapolations that are very significant in archaeology.

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Influence fast or later: two types of influencers in social networks

Chinese Physics B ◽

10.1088/1674-1056/ac4484 ◽

2021 ◽

Author(s):

Fang Zhou ◽

Chang Su ◽

Shuqi Xu ◽

Linyuan Lü

Keyword(s):

Final Stage ◽

Early Stage ◽

Large Fraction ◽

Structure And Function ◽

Spreading Process ◽

Spreading Effect ◽

Local Structures ◽

Different Types ◽

Small Set ◽

And Function

Abstract In real-world networks, there usually exist a small set of nodes that play an important role in the structure and function of networks. Those vital nodes can influence most other nodes in the network via a spreading process. While most of the existing works focused on vital nodes that can maximize the spreading size in the final stage, which we call final influencers, recent work proposed the idea of fast influencers, which emphasizes nodes’ spreading capacity at the early stage. Despite the recent surge of efforts in identifying these two types of influencers in networks, there remained limited research on untangling the differences between fast influencers and final influencers. In this paper, we first distinguish the two types of influencers: fast-only influencers and final-only influencers. The former is defined as individuals who can achieve a high spreading effect at the early stage but lose their superiority in the final stage, and the latter are those individuals that fail to exhibit a prominent spreading performance at the early stage but influence a large fraction of nodes at the final stage. Further experiments based on eight empirical datasets, we reveal the key differences between the two types of influencers concerning their spreading capacity and the local structures. We also analyze how network degree assortativity influences the fraction of the proposed two types of influencers. The results demonstrate that with the increase of degree assortativity, the fraction of the fast-only influencers decreases, which indicates that more fast influencers tend to keep their superiority at the final stage. Our study provides insights into the differences and evolution of different types of influencers and has important implications for various empirical applications, such as advertisement marketing, and epidemic suppressing.

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Recent advances in polymer shell-oily core nanocapsules for drug delivery applications

Nanomedicine ◽

10.2217/nnm-2021-0037 ◽

2021 ◽

Author(s):

Ahmed S AbdElhamid ◽

Dina G Zayed ◽

Lamia Heikal ◽

Sherine N Khattab ◽

Omar Y Mady ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Early Stage ◽

Controlled Drug Release ◽

Delivery Systems ◽

Polymeric Membranes ◽

Polymer Shell ◽

Recent Advances ◽

Target Sites ◽

Different Types

Polymeric nanocapsules are vesicular drug delivery systems composed of an inner oily reservoir surrounded by polymeric membranes. Nanocapsules have various advantages over other nanovesicular systems such as providing controlled drug release properties. We discuss the recent advances in polymeric shell-oily core nanocapsules, illustrating the different types of polymers used and their implementation. Nanocapsules can be utilized for many purposes, especially encapsulation of highly lipophilic drugs. They have been shown to have variable applications, especially in cancer therapy, due to the ability of the polymeric shell to direct the loaded drugs to their target sites, as well as their high internalization efficacy. Those productive applications guaranteed their high potential as drug delivery systems. However, their clinical development is still in an early stage.

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Adhesives for the Installation of Cast Basalt Elements on Metal and Comparison of Properties when Using Different Types of Fillers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.898.35 ◽

2021 ◽

Vol 898 ◽

pp. 35-41

Author(s):

Jakub Hodul ◽

Tomáš Žlebek ◽

Lenka Mészárosová ◽

Aleš Jakubík ◽

Rostislav Drochytka

Keyword(s):

Construction Industry ◽

Raw Materials ◽

Physical And Mechanical Properties ◽

Mineral Admixtures ◽

Maximum Efficiency ◽

Organic Additives ◽

Metal Base ◽

Secondary Raw Materials ◽

Ecological Benefit ◽

Different Types

The polymeric adhesives for the installation of basalt elements on a metal base are designed primarily for environments with increased chemical and mechanical stress. They are composed of polymer resins (epoxy, polyurethane) as binders, as well as organic additives and mineral admixtures that mainly fulfill the function of filler. In all sectors of today's construction industry, maximum efficiency in the production of materials is required for sustainability purposes, which, however, must never be at the expense of the quality or the required performance. Due to these requirements, great emphasis is placed on the maximum use of secondary raw materials. Talc is used as the primary filler for polymer adhesives. Sawdust, tire rubber, and fly ash are used as secondary raw materials. The use of these in building supplies can positively affect some physical and mechanical properties of polymeric adhesives. Also, the use of secondary raw materials has the above-mentioned ecological benefit. Basic properties, such as bulk density and adhesion to both metallic and basalt elements, were monitored. The details of the cohesion of the adhesive with the bonded material, as well as the distribution of secondary raw materials in the polymer matrix, were assessed microscopically.

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Analyzing the Manufacturing Supply Chain Performance for Urgent Item During COVID-19 Outbreak

Industrial and Systems Engineering Review ◽

10.37266/iser.2021v9i1.pp15-31 ◽

2021 ◽

Vol 9 (1) ◽

pp. 15-31

Author(s):

Ali Arishi ◽

Krishna K Krishnan ◽

Vatsal Maru

Keyword(s):

Raw Materials ◽

Early Stage ◽

Supply And Demand ◽

Network Models ◽

Combine System ◽

Neural Network Models ◽

Digital Twin ◽

Twin Model ◽

The Impact ◽

Reaction Patterns

As COVID-19 pandemic spreads in different regions with varying intensity, supply chains (SC) need to utilize an effective mechanism to adjust spike in both supply and demand of resources, and need techniques to detect unexpected behavior in SC at an early stage. During COVID-19 pandemic, the demand of medical supplies and essential products increases unexpectedly while the availability of recourses and raw materials decreases significantly. As such, the questions of SC and society survivability were raised. Responding to this urgent demand quickly and predicting how it will vary as the pandemic progresses is a key modeling question. In this research, we take the initiative in addressing the impact of COVID-19 disruption on manufacturing SC performance overwhelmed by the unprecedented demands of urgent items by developing a digital twin model for the manufacturing SC. In this model, we combine system dynamic simulation and artificial intelligence to dynamically monitor SC performance and predict SC reaction patterns. The simulation modeling is used to study the disruption propagation in the manufacturing SC and the efficiency of the recovery policy. Then based on this model, we develop artificial neural network models to learn from disruptions and make an online prediction of potential risks. The developed digital twin model is aimed to operate in real-time for early identification of disruptions and the respective SC reaction patterns to increase SC visibility and resilience.

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Survey and Documentation of Ethnobotanicals used in the Traditional Medicines System of Tribal Communities of Chirang District of Assam Against Helminthiasis

Biomedical & Pharmacology Journal ◽

10.13005/bpj/1824 ◽

2019 ◽

Vol 12 (04) ◽

pp. 1923-1935

Author(s):

Ananta Swargiary ◽

Mritunjoy Kumar Roy ◽

Manita Daimari

Keyword(s):

Sex Education ◽

Raw Materials ◽

Herbal Medicines ◽

Ananas Comosus ◽

Asparagus Racemosus ◽

Traditional Medicines ◽

Face To Face ◽

Plant Parts ◽

Tribal Communities ◽

Ancient Times

Ethnobotanical knowledge has been the backbone of rural healthcare since ancient times. Many diseases including helminthiasis are cured by traditional medicine in many parts of the world. The present study aims at exploring the ethnobotanicals used as anthelmintic medicines by the tribal communities of Chirang district of Assam. The present study was conducted in different villages under Chirang district of Assam, India. A face-to-face interview was carried out during survey work along with readymade questionnaire. In our survey work, 20 neighbouring villages were taken as a single cluster and one sample informant was collected. Information regarding the plant and plant parts used, methodology of use as well as informant demography such as age, sex, education was also collected. A total of 20 villages were surveyed and information was gathered from 27 informants, 23 kaviraja and 4 elderly people, 15 male and 12 female. The information collected revealed 43 medicinal plants belonging to 27 families. Lamiaceae was found to be most common family followed by Cucurbitaceae, Fabaceae, Zutaceae and Zingiberaceae. The most highly cited plants were Ananas comosus, Andrographis paniculata, Asparagus racemosus, Alstonia scholaris and Leucas aspera. Leaves, fruits and tubers were found to be the most commonly used plant parts. Except few, most of the herbal medicines were prepared as raw materials and are consumed orally. Documentation of important ethnomedicinal information from the remote areas of Assam will help scientific investigators to look into its scientific aspect leading to the development of new medicines against helminthiasis and many other diseases.

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Probable evidence of a Middle Palaeolithic site in the northern parts of the Susiana Plain, Khuzestan, Iran

Documenta Praehistorica ◽

10.4312/dp.46-27 ◽

2019 ◽

Vol 46 ◽

pp. 424-433

Author(s):

Saeid Bahramiyan

Keyword(s):

Raw Materials ◽

Middle Palaeolithic ◽

Limited Information ◽

Zagros Mountains ◽

Significant Progress ◽

Khuzestan Province ◽

Different Types ◽

Northern Regions ◽

Considerable Body ◽

The Karkheh River

There is a considerable body of studies regarding the activities of the Pleistocene human population in the Zagros and Alborz regions of Iran, as well as significant progress in the Palaeolithic studies in other regions, such as the foothills, plains and deserts’ margins. However, some of these peripheral regions and foothills are still neglected, and the information about the Palaeolithic period in these areas is limited. Khuzestan province, especially its northern regions, is one of these unstudied regions, yet the limited information about this region seems very interesting. Khervali, located on the western foothills of the Zagros Mountains and on the northern heights of Susa, nearby the western bank of the Karkheh River, is one of the few Palaeolithic sites identified in recent years. The site was identified in 2012 and was systemically surveyed. Due to the extension of the site and the distribution of the artefacts, sampling all the site was not feasible, therefore, four sections of the site were chosen for taking the samples and a total of 330 stone artefacts were collected. The results of the techno-typology analyses, as well as the frequency of the flakes, the Levallois samples and different types of scrapers, revealed that the artefacts date to the middle Palaeolithic period, with considerable access to the local raw materials.

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