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191.
Little is known about the concentrations, deposition rates, and effects of nitrogenous and sulfurous compounds in photochemical smog in the San Bernardino National Forest (SBNF) in southern California. Dry deposition of NO(3)(-) and NH(4)(+) to foliage of ponderosa pine (Pinus ponderosa Laws.) and Jeffrey pine (Pinus jeffreyi Grev. & Balf.) was correlated (R = 0.83-0.88) with historical average hourly O(3) concentations at 10 sites across an O(3) gradient in the SBNF. Mean deposition fluxes of NO(3)(-) to ponderosa and Jeffrey pine branches were 0.82 nmol M(-2)s(-1) at Camp Paivika (CP), a high-pollution site, and 0.19 nmol m(-2) s(-1) at Camp Osceola (CAO), a low-pollution site. Deposition fluxes of NH(4)(+) were 0.32 nmol m(-2) s(-1) at CP and 0.17 nmol m(-2) s(-1) at CAO, while mean values for SO(4)(2-) were 0.03 at CP and 0.02 nmol m(-2) s(-1) at CAO. Deposition fluxes to paper and nylon filters were higher in most cases than fluxes to pine branches at the same site. The results of this study suggest that an atmospheric concentration and deposition gradient of N and S compounds occurs along with the west-east O(3) gradient in the SBNF. Annual stand-level dry deposition rates for S and N at CP and CAO were estimated. Further studies are needed to determine if high N deposition loads in the SBNF significantly affect plant/soil nutrient relations, tree health, and the response of ponderosa pine to ozone.  相似文献   
192.
This article discusses the problems facing refinery operations in developing countries and possible solutions to them. The topics covered include security of crude oil supply to the developing countries; difficulties encountered in development of indigenous expertise in refinery operation; refinery capacity and the special problems of maintenance and repair facing refinery operators in the developing parts of the world; and the potential for improved refinery operation through increased international co-operation.  相似文献   
193.
194.
Epidemiological procedures can be organised under disaster conditions by means of a simple surveillance system and with few personnel.
In the aftermath of the 4 February 1976 earthquake in Guatemala, an information system was organized by which the requisite information for decision-making was obtained with adequate speed and promptness.
The initial epidemiologic informution was based on reports collected during the early days on symptoms observed at hospitals and health centers and in localities and villages in the stricken area.
At a second, post-emergency stage a more elaborate surveillance system was instituted to provide guidance in the investigntwn of outbreaks, evaluate the health activities and establish basic criteria for preventive and control measures.  相似文献   
195.
196.
Natural gas may provide a major contribution to the world energy supply during the next few decades. The developing countries command about 50 per cent of the world proved natural gas reserves, with gas accounting for only 6 per cent of commercial primary energy production. The challenging task of expanding gas production and utilization in the developing countries, especially through effective use of gas associated with petroleum deposits and transportation of gas in liquefied form (LNG), will require long-term technical co-operation policy commitments with regard to investment, manpower and the transfer of technology. The article is intended to analyse the basic factors involved in these problems. Au cours des prochaines décennies, le gaz naturel peut constituer un apport considérable à l'approvisionnement énergétique mondial. Les pays en développement détiennent approximativement 50 pour cent des réserves mondiales prouvées de gaz naturel, le gaz représentant seulement 6 pour cent de la production d'énergie primaire commerciale. Le défi lancé par la production et l'utilisation croissantes de gaz dans les pays en développement, particulièrement par l'utilisation efficace du gaz lié aux gisements de pétrole et le transport du gaz liquéfié (GNL), requiert des engagements à long terme en matière de politique de coopération technique dans le domaine des investissements, de la main-d'oeuvre et du transfert de technologie. Cet article a pour but d'analyser les facteurs fondamentaux à prendre en considération lorsqu'on traite de ces problèmes. El gas natural podría representar una gran contribucíon a la oferta mundial de energía dentro de las próximas décadas. Los países en desarrollo poseen cerca del 50 porciento de la reserva provada mundial de gas y solamente el 6 porciento de la producción primaria de energía comercial proviene del gas. La tarea de expandir la producción y utilización de gas en los países en desarrollo, especialmente ia utilización efectiva en forma líquida (LNG) de gas asociado al petróleo, requiere de compromisos de cooperación técnica a largo plazo en lo referente a inversiones, recursos humanos y transferencia de tecnología. Este artículo intenta analizar los factores básicos pertinentes a dicha tarea.  相似文献   
197.
Resource estimates alone will not give advance warning of encroaching production difficulties. An analysis of the general stages in the evolution of petroleum production and discovery and of industry statistics provides an estimate of when the stage characterised by increasing production in the market economy countries outside the United States and Canada will end. The analysis indicates that the year of maximum production will be in the 1990s. Economic growth aggravates the difficulties accompanying the production decline by advancing the date of peak production and by increasing the adjustments that must be made as oil production declines. Des prévisions de ressources à elles seules ne constituent pas des signes précurseurs de difficultés croissantes de production. Une analyse des étapes générales marquant l'evolution de la découverte et de la production du pétrole ainsi que des statistiques industrielles nous permet de prévoir l'époque à laquelle prendra fin la phase de production accrue dans les pays à économie de marché en dehors des Etats-Unis et du Canada. Cette analyse révèle que l'année de production maximale se situera dans les années 90. La croissance économique accentue les difficultés qui accompagnent le déclin de la production de pétrole en avancant la date à laquelle cell-ci atteindra son plafond et en augmentant le nombre d'ajustements qui s'avèrent nécessaires au fur et à mesure qu'elle baisse. Las evaluaciones de recursos no dan por si solas un aviso anticipado de las dificultades de producción. Un análisis de las etapas principales en la evolución del descubrimiento y producción de petróleo y de las estadísticas industriales provee un estimado de cuando va a terminar la etapa caracterizada por un crecimiento de producción en los paises de economias de mercado otros que Estados Unidos y Canada. El análisis indica que el año de producción máxima se hallará en la década del 90. El crecimiento económico agrava las dificultades debidas a la declinación de la producción al adelantar la fecha de máxima producción (pico) y al aumentar los ajustes que deven hacerse cuando la producción de petróleos disminuye.  相似文献   
198.
Sharlin SA  Mor-Barak M 《Disasters》1983,7(2):142-147
This paper describes the help given by the social services department of a shipping company to bereaved families following a shipping disaster. In the absence of clear, factual and prompt information from an authoritative source, there is a tendency for bereaved individuals to deny their loss and thereby delay the process of mourning and eventual recovery. Appropriate intervention and support can help to overcome this tendency as was seen in the Madasa case.  相似文献   
199.
Results of a recent intercomparison on the determination of trace elements in simulated air filter samples are reported. A large scatter of results is obtained for some elements and systematic differences between laboratories are observed. The performance of different methods, in particular neutron activation analysis and atomic absorption spectrophotometry, used by the various laboratories is discussed (air filter analysis; intercomparison; trace elements; control charts).  相似文献   
200.
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