Public policy and future mineral supplies

A widespread and pessimistic view of the availability of mineral commodities calls for strong government initiatives to ensure adequate future supplies. This article provides a more market oriented and optimistic perspective, one that focuses on production costs and prices rather than physical availability. It sees short-run shortages continuing to plague commodity markets in the future as in the past. Though painful while they last, these shortages are temporary and do not pose a serious long-run threat to human welfare. Moreover, even without government intervention, they self-correct. The sharply higher prices that they evoke create strong incentives that foster supply and curb demand. Potentially more serious are long-run shortages due to mineral depletion. Such shortages are often thought to be inevitable, a conclusion that flows directly from the physical view of depletion. For various reasons, we reject this view of depletion in favor of an economic view. The latter recognizes that depletion may create long-run shortages, but stresses that this need not be the case if new technology can continue to offset the cost-increasing effects of depletion in the future as it has in the past. The economic view also suggests that a list of mineral commodities most threatened by depletion can best be compiled using cumulative availability curves rather than the more common practice of calculating commodity life expectancies based on estimates of available stocks.<p>Validerad;2018;Nivå 2;2018-08-08 (rokbeg)</p

Regioisomeric and substituent effects upon the outcome of the reaction of 1-borodienes with nitrosoarene compounds

A study of the reactivity of 1-borodienes with nitrosoarene compounds has been carried out showing an outcome that differs according to the hybridization state of the boron moiety. Using an sp2 boron substituent, a one-pot hetero-Diels–Alder/ring contraction cascade occurred to afford N-arylpyrroles with low to good yields depending on the electronic properties of the substituents on the borodiene, whereas an sp3 boron substituent led to the formation of stable boro-oxazines with high regioselectivity in most of the cases, in moderate to good yields. 1H and 11B NMR studies on two boro-oxazine regioisomers showed that selective deprotection can be performed. Formation of either the pyrrole or the furan derivative is pH- and regioisomer-structure-dependent. The results obtained, together with previous B3LYP calculations, support mechanistic proposals which suggest that pyrrole, or furan, formation proceeds via oxazine formation, followed by a boryl rearrangement and an intramolecular addition–elimination sequence

Analysis of the impact of sex and age on the variation in the prevalence of antinuclear autoantibodies in Polish population: a nationwide observational, cross-sectional study

The detection of antinuclear autoantibody (ANA) is dependent on many factors and varies between the populations. The aim of the study was first to assess the prevalence of ANA in the Polish adult population depending on age, sex and the cutoff threshold used for the results obtained. Second, we estimated the occurrence of individual types of ANA-staining patterns. We tested 1731 patient samples using commercially available IIFA using two cutoff thresholds of 1:100 and 1:160. We found ANA in 260 participants (15.0%), but the percentage of positive results strongly depended on the cutoff level. For a cutoff threshold 1:100, the positive population was 19.5% and for the 1:160 cutoff threshold, it was 11.7%. The most prevalent ANA-staining pattern was AC-2 Dense Fine speckled (50%), followed by AC-21 Reticular/AMA (14.38%) ANA more common in women (72%); 64% of ANA-positive patients were over 50 years of age. ANA prevalence in the Polish population is at a level observed in other highly developed countries and is more prevalent in women and elderly individuals. To reduce the number of positive results released, we suggest that Polish laboratories should set 1:160 as the cutoff threshold

Technical maintenance of production process continuity in a light industry enterprise

W artykule przedstawiono wybrane zagadnienia związane z szeroko pojętym technicznym zabezpieczeniem ciągłości procesu produkcyjnego w zakresie systemów utrzymania ruchu oraz ich niezawodności w dużym przedsiębiorstwie odzieżowym. Celem autora było określenie niezawodności mechanizmów maszyn, które wpływają bezpośrednio na techniczne utrzymanie ciągłości procesu produkcji, oraz zaproponowanie odpowiednich działań prewencyjnych i korygujących. W pierwszej części artykułu dokonano analizy przyczyn braku ciągłości procesu produkcyjnego ustalonych na podstawie studiów literaturowych oraz obserwacji własnych. W drugiej części przedstawiono wyrywkowo badania własne dotyczące niezawodności wybranej maszyny szwalniczej typu Pfaff 3588. W podsumowaniu zaproponowano działania profilaktyczno-korekcyjne mające na celu poprawę stosowanego w przedsiębiorstwie systemu utrzymania ruchu.The study presents selected issues related to a broadly defined technical maintenance of production process continuity in the scope of productive maintenance systems and their reliability in a large clothing enterprise. In a given period of time every real technical system undergoes various changes which may result from spontaneous processes or external influences directly affecting its reliability. The first part of the article contains the analysis of reasons for absence of production process continuity based on literature research and individual observations. The second part presents random individual research related to reliability of a selected Pfaff 3588 automatic sewing unit. The conclusion contains the suggested preventive and corrective actions aimed at improvement of a functioning productive maintenance system

Assessment of residual life of ammonia reformers catalytic pipes by NDT test

The article presents the results of the stability of the microstructure and properties of catalytic cast pipes in steam reforming conditions. The growing prices of catalytic pipes have resulted in the attempts to prolong of the pipe work above 100,000 h stability. Increasing the time and temperature of operating causes coalescence and coagulation of secondary carbides reducing thus the creep resistance of the alloy. Currently there is no definite and commonly used method to assess the degree of degradation of the microstructure and properties of catalytic pipes. The destructive test methods of catalytic pipes are usually reduced to the assessment of the effects of metallographic creeping process, ie. relative volume and distribution of mikrovoids on the pipe wall section, as well as evaluating the mechanical properties of steel. These methods generally give a clear assessment but require disassembly for testing pipes and replace ment with new ones. The author developed the regression which show a significant dependence of mechanical properties (Rm A5, KCU 2) on the operating parameters of the reformer (PLM, σ) and hardness HB cast IN 519. The equations have been applied to assess the possibility of using non-destructive testing for the assessment of the degree of degradation of the catalyst steel pipe.W artykule przedstawiono wyniki badań stabilności mikrostruktury i właściwości staliwa rur katalitycznych w warunkach reformingu parowego. Wzrastające ceny rur katalitycznych doprowadziły do analizy możliwości przedłużenia czasu eksploatacji rur powyżej projektowej trwałości 100000 h. Zwiększenie czasu i temperatury eksploatacji powoduje koalescencję i koagulację węglików wtórnych, a tym samym zmniejszenie odporności na pełzanie stopu. Obecnie brak jest jednoznacznej i powszechnie stosowanej metody oceny stopnia degradacji mikrostruktury i właściwości staliwa rur katalitycznych. Niszczące metody badań rur katalitycznych sprowadzają sie zwykle do oceny metalograficznej efektów procesu pełzania, tzn. objętości względnej i rozmieszczenie mikropustek na przekroju ścianek rur, a także ocenę właściwości mechanicznych staliwa. Metody te dają na ogół jednoznaczną ocenę ale wymagają demontażu rur do badań i zastąpienie ich nowymi. Wykorzystując opracowane równania regresji wykazujące istotną statystycznie zależność właściwości mechanicznych (Rm, A5, KCU 2) od parametrów eksploatacyjnych reformera (PLM, σ) i twardości HB staliwa IN 519, wykazano możliwość zastosowania badań nieniszczących do oceny stopnia degradacji staliwa rur katalitycznych

Legal and administrative framework for investments in the geological-mining sector in the Socialist Republic of Vietnam

Main frames of the now-a-day Law of Vietnam on prospecting, exploration, mining and processing of minerals has been presented. Within the scope of this article are included : Mineral Law (provides for the management, protection and basic geological surveys of mineral resources and mineral activities including prospecting, exploring, mining and processing of minerals in solid and gaseous forms, mineral water and natural thermal water, except oil and gas and other types of natural water, which shall be subjected to separate legal regulations), Law on amendments and supplement of some articles of the Mineral Law (amends and supplements some articles of the above mentioned Mineral Law) and Decree of the Government stipulating detailed provisions on the implementation of the law on amendment and supplement of some articles of the Mineral Law (provides detailed regulations for the implementation of the Mineral Law and of the Law on amendments and supplement of some articles of the Mineral Law). The possibilities of the geological mining activities of foreign entrepreneurs in Vietnam have been presented. Some indications of the legal-organizational origin, valuable to undertake successful activity, have been suggested

Electronic handling of analysis results of copper deposit samples KGHM Polska Miedź S.A.

W artykule opisano rozwiązanie umożliwiające obsługę oznaczeń laboratoryjnych prób złożowych przy pomocy usług sieciowych. Proces wymiany informacji na każdym z etapów odbywa się w pełni elektronicznie: zarówno na etapie przygotowywania zlecenia wykonania analizy, jak i w trakcie weryfikacji oraz zapisu wyników oznaczeń do Bazy Danych Geologicznych KGHM Polska Miedź S.A.This paper describes a solution to support laboratory tests of samples of using IT solutions. The exchange of information at each stage is fully electronically: both at the stage of preparing to order the analysis as well as during the verification test results and records the Geological Database KGHM Polish Copper S.A