92 research outputs found

    The influence of temperature on the speed of reduction of TIN oxide with argon- hydrogen mixture

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    Recently, the usage of hydrogen in the processes of metal extraction has been a very important challenge to metallurgic industry. Replacing conventional reductor, taking into consideration CO2 emission restrictions will enable maintaining and developing this branch of industry. The results of the research on tin oxide SnO reduction using hydrogen given as a mixture Ar – 5 % vol.H2 in temperature range 773 – 873 K. are shown in this article. The tests were conducted using thermogravimetric method. It is demonstrated that with the rise of a temperature in the analyzed range the speed of reaction rises as well and the obtained degree of reduction varies from 40 to 99,5 %. Stabilization the weight change in the tested sample thermogravimetric (TG) was reached after from 25 min for 773 K to 15 min for temperature 873 K

    The influence of temperature on the speed of reduction of TIN oxide with argon- hydrogen mixture

    Get PDF
    Recently, the usage of hydrogen in the processes of metal extraction has been a very important challenge to metallurgic industry. Replacing conventional reductor, taking into consideration CO2 emission restrictions will enable maintaining and developing this branch of industry. The results of the research on tin oxide SnO reduction using hydrogen given as a mixture Ar – 5 % vol.H2 in temperature range 773 – 873 K. are shown in this article. The tests were conducted using thermogravimetric method. It is demonstrated that with the rise of a temperature in the analyzed range the speed of reaction rises as well and the obtained degree of reduction varies from 40 to 99,5 %. Stabilization the weight change in the tested sample thermogravimetric (TG) was reached after from 25 min for 773 K to 15 min for temperature 873 K

    The effect of organic acids as leaching agents for hydrometallurgical recovery of metals from PCBs

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    The hydrometallurgical treatment, compared to other recycling processes, is of great interest due to its higher efficiency and better economy. In hydrometallurgy, popular agents used in the leaching processes of e-waste include inorganic acids, ammonia, chlorides, thiourea, thiosulphates. Organic acids are also becoming more and more popular. The article presents an overview of possible paths of the metal recovery from e-waste with the use of various organic acids. The results of own research on the leaching of printed circuit boards with the use of organic acids including citric acid, oxalic acid, acetic acid, formic acid, malic acid, lactic acid are also presented

    The effect of organic acids as leaching agents for hydrometallurgical recovery of metals from PCBs

    Get PDF
    The hydrometallurgical treatment, compared to other recycling processes, is of great interest due to its higher efficiency and better economy. In hydrometallurgy, popular agents used in the leaching processes of e-waste include inorganic acids, ammonia, chlorides, thiourea, thiosulphates. Organic acids are also becoming more and more popular. The article presents an overview of possible paths of the metal recovery from e-waste with the use of various organic acids. The results of own research on the leaching of printed circuit boards with the use of organic acids including citric acid, oxalic acid, acetic acid, formic acid, malic acid, lactic acid are also presented

    The effect of organic acids as leaching agents for hydrometallurgical recovery of metals from PCBs

    Get PDF
    The hydrometallurgical treatment, compared to other recycling processes, is of great interest due to its higher efficiency and better economy. In hydrometallurgy, popular agents used in the leaching processes of e-waste include inorganic acids, ammonia, chlorides, thiourea, thiosulphates. Organic acids are also becoming more and more popular. The article presents an overview of possible paths of the metal recovery from e-waste with the use of various organic acids. The results of own research on the leaching of printed circuit boards with the use of organic acids including citric acid, oxalic acid, acetic acid, formic acid, malic acid, lactic acid are also presented.Web of Science613-461260

    An in vivo screen identifies ependymoma oncogenes and tumor-suppressor genes

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    Cancers are characterized by non-random chromosome copy number alterations that presumably contain oncogenes and tumor-suppressor genes (TSGs). The affected loci are often large, making it difficult to pinpoint which genes are driving the cancer. Here we report a cross-species in vivo screen of 84 candidate oncogenes and 39 candidate TSGs, located within 28 recurrent chromosomal alterations in ependymoma. Through a series of mouse models, we validate eight new ependymoma oncogenes and ten new ependymoma TSGs that converge on a small number of cell functions, including vesicle trafficking, DNA modification and cholesterol biosynthesis, identifying these as potential new therapeutic targets.We are grateful to F.B. Gertler (Massachusetts Institute of Technology) and S. Gupton (University of North Carolina) for the generous gift of the VAMP7-phlorin construct and the staffs of the Hartwell Center for Bioinformatics and Biotechnology, the Small Animal Imaging Center, the Animal Resources Center, the Cell and Tissue Imaging Center, and the Flow Cytometry and Cell Sorting Shared Resource at St. Jude Children's Research Hospital for technical assistance. This work was supported by grants from the US National Institutes of Health (R01CA129541, P01CA96832 and P30CA021765, R.J.G.), by the Collaborative Ependymoma Research Network (CERN) and by the American Lebanese Syrian Associated Charities (ALSAC)

    Diversity of muskox Ovibos moschatus (Zimmerman, 1780) (Bovidae, Mammalia) in time and space based on cranial morphometry

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    Muskox Ovibos moschatus is a Pleistocene relic, which has survived only in North America and Greenland. During the Pleistocene, it was widely distributed in Eurasia and North America. To evaluate its morphological variability through time and space, we conducted an extensive morphometric study of 217 Praeovibos and Ovibos skull remains. The analyses showed that the skulls grew progressively wider from Praeovibos sp. to the Pleistocene O. moschatus, while from the Pleistocene to the recent O. moschatus, the facial regions of the skull turned narrower and shorter. We also noticed significant geographic differences between the various Pleistocene Ovibos crania. Siberian skulls were usually larger than those from Western and Central Europe. Eastern Europeanmuskoxen also exceeded in size those from the other regions of Europe. The large size of Late Pleistocene muskoxen from regions located in more continental climatic regimes was probably associated with the presence of more suitable food resources in steppe-tundra settings. Consistently, radiocarbon-dated records of this species are more numerous in colder periods, when the steppe-tundra was widely spread, and less abundant in warmer periods

    How to combat cyanobacterial blooms: strategy toward preventive lake restoration and reactive control measures

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    Adsorption of chromium(III) and chromium(VI) ions on nanoporous aluminum oxide

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    Współczesne metody spektroskopowe i elektrochemiczne nie zawsze pozwalają na oznaczanie pierwiastków toksycznych takich jak chrom(VI) w bardzo niskim zakresie stężeń. Z tego powodu konieczne jest zastosowanie technik zatężania analitów. Jedną z najczęściej stosowanych technik wzbogacania jest ekstrakcja do fazy stałej. Istotne jest odpowiednie dobranie adsorbentu (fazy stałej). W pracy przebadano możliwość adsorpcji jonów chromu(III) oraz chromu(VI) na nanoporowatym tlenku glinu. Przeprowadzono odpowiednią modyfikację tlenku glinu z wykorzystaniem (3-mercaptopropyl)trimetoksysilanu (MPTMS) mającą na celu wprowadzenie grup tiolowych zdolnych do kompleksowania jonów metali. Przebadano wpływ środowiska reakcji na proces adsorpcji. Efekt modyfikacji adsorbentu weryfikowano z zastosowaniem techniki rentgenowskiej spektrometrii fluorescencyjnej z dyspersją energii (EDXRF). Pomiary stężenia jonów chromu(III) oraz jonów chromu (VI) prowadzono z wykorzystaniem emisyjnej spektrometrii atomowej ze wzbudzeniem w plazmie sprzężonej indukcyjnie (ICP OES).Modern spectroscopic and electrochemical methods do not always allow the determination of elements toxic to a very low concentration range, such as chromium (VI). Therefore, analytical concentration techniques are used, and one of the most commonly used is solid phase extraction. In this method, it is important to choose the appropriate adsorbent (solid phase). The study investigated the adsorption of chromium (III) and chromium (VI) ions on nanoporous alumina. An appropriate modification of aluminum oxide was carried out using (3-mercaptopropyl) trimethoxysilane (MPTMS) to introduce thiol groups capable of complexing metal ions. The influence of the reaction environment on the adsorption process was tested. The effect of adsorbent modification was verified using energy dispersive X-ray fluorescence (EDXRF). Measurements of chromium (III) ions and chromium (VI) ions were carried out using inductively coupled plasma optical emission spectrometry (ICP OES)
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