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81.
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Conference news     
RESOURCES: ENVIRONMENT AND POLICY, by John Fernie and Alan Pitkethly, Harper and Row, London, 1985, 338 pp. (#bp12.95, paperback)

THE ECONOMICS OF FORESTRY AND NATURAL RESOURCES, by Per‐Olov Johansson and Karl‐Gustaf Lofgren, Basil Blackwell, Oxford, 1985, 292 pp. (#bp29.50, hardback only)

ENVIRONMENTAL PROTECTION: STANDARDS, COMPLIANCE AND COSTS, edited by T. J. Lack, J. Wiley &; Son, Chichester, 1984, 329 pp. (#bp30, hardback)

ENVIRONMENT AND ENFORCEMENT: REGULATION AND THE SOCIAL DEFINITION OF POLLUTION, by K. Hawkins, Clarendon Press, Oxford, 1984, 253 pp. (#bp15 hardback; #bp6.95, paperback)

ENVIRONMENTAL POLICY, VOLUME 1: ELEMENTS OF ENVIRONMENTAL ANALYSIS, by George Tolley, Philip Graves and Glenn Blomquist, Ballinger, Cambridge, Mass, and Harper and Row, London, 1981. (#bp27.50, hardback)

ENVIRONMENTAL POLICY, VOLUME 4: SOLID WASTES, by George Tolley, Jospeh Havlicek and Robert Fabian, Ballinger, Cambridge, Mass. and Harper and Row, London, 1985. (#bp44.00, hardback)

World Health Organisation, ENVIRONMENTAL POLLUTION CONTROL IN RELATION TO DEVELOPMENT, World Health Organisation, Geneva, Technical Report Series, 718, 1985, 63 pp.

TRANSPORT IS FOR PEOPLE: NINTH INTERNATIONAL SYMPOSIUM ON THEORY AND PRACTICE IN TRANSPORT ECONOMICS, European Conference of Ministers of Transport, 1983, Paris (#bp15.00)

RECREATION MANAGEMENT AND PRICING, by A. G. Bovaird, M. J. Tricker and R. Stoakes, Gower Press, Aldershot, 1984, 182 pp. (#bp15, hardback)

URBAN LAND AND SHELTER FOR THE POOR, by Patrick McAuslan, Earthscan#shInternational Institute for Environment and Development, London, 1985, 145 pp.

CARING FOR THE UNEMPLOYED. Prepared for the Association of Metro‐polital Authorities by Susan Balloch, Chris Hume, Brian Jones and Peter Westland. Publishers: Bedford Square Press, London, 1985, for the National Council for Voluntary Organisations.

THE LONG‐TERM UNEMPLOYED. ACTION FOR A FORGOTTEN MILLION, by Peter Ashby (Head, NVCO Policy Analysis Unit). An NCVO Policy Discussion document, Bedford Square Press, London (1985).

ANTHROPOGENIC COMPOUNDS: Volume 3 Part C of The Handbook of Environmental Chemistry, edited by O. Hutzinger, Springer‐Verlag, Germany, 248 pp. 1986. (DM 188.00)

HEAVY METALS IN NATURAL WATERS: APPLIED MONITORING AND IMPACT ASSESSMENT, by James W. Moore and S. Ramamoorthy, Springer‐Verlag, U.S.A. and Germany, viii #pl 268 pages, index, 1984. (DM 108.00)

DESTRUCTION AND DISPOSAL OF PCBs BY THERMAL AND NON‐THERMAL METHODS, by D. G. Ackerman, L. L. Scinto, P. S. Bakshi, R. G. Delumyea, R. J. Johnson, G. Richard, A. M. Takata and E. M. Sworzyn. Noyes Data Corporation, Park Ridge, New Jersey, 1983, xiv #pl 417 pages (no index). (#dl48.00)

ELECTROSTATIC PRECIPITATOR MANUAL (Pollution Technology Review No. 91), by Jack R. McDonald and Alan H. Dean, Noyes Data Corporation, U.S.A., 1982. (#dl48.00)

PATTY'S INDUSTRIAL HYGIENE AND TOXICOLOGY, edited by Lewis J. Cralley and Lester V. Cralley, Volume 3 (2nd Edition)—Theory and Rationale of Industrial Hygiene Practice: (i) Volume 3A—The Work Environment (#bp97.20); (ii) Volume 3B—Biological Responses (#bp92.00) J. Wiley and Sons Ltd., Chichester U.K. 1985.

SAFE DRINKING WATER. THE IMPACT OF CHEMICALS ON A LIMITED RESOURCE, edited by R. G. Rice, J. Wiley and Sons, Chichester, U.K., Lewis Publishers Inc. Chelsea MI, 1985. (#bp36.00)

PLANTS FOR ARID LANDS. (Proceedings of the Kew International Conference on Economic Plants for Arid Lands held in the Jodrell Laboratory, Royal Botanic Gardens, Kew, England, 23‐27 July 1984), edited by G. E. Wickens, J. R. Goodwin and D. V. Field. George Allen and Unwin, London, 1985. (#bp30.00)

REGULATED RIVERS, edited by A. Lillehammer and S. J. Saltveit, Univer‐sitetsforlaget AS, Oslo, 1984. (#bp47.50)

NUTRIENT CYCLING IN TROPICAL FOREST ECOSYSTEMS, by C. F. Jordan, Wiley, Chichester, 1985. (#bp13.45)  相似文献   
83.
County manufacturing employment can be projected for the purpose of verifying a population projection. First, future county manufacturing employment is derived from a population projection by using assumed ratios of labor force participation, unemployment, and manufacturing employment. Second, independent projections of manufacturing employment are made, based upon statistical projections of county and national manufacturing employment trends. Third, both these quantitative projections are checked against the knowledge and judgments of leading businessmen and industrialists in the community, and adjustments are made in the quantities.  相似文献   
84.
Dynamic modeling of processes involving phase changes can be challenging due to changes in the model equations caused by appearance and disappearance of equilibrium phases. Dynamic simulation of these processes requires the ability to detect the change in the number of phases and adapt the model to the new phase regime on the fly. In this work, an easy‐to‐use nonsmooth model for dynamic simulation of processes with vapor‐liquid equilibrium is presented. The presented model does not introduce any auxiliary variables or equations, nor does it require solution of an optimization problem to determine the new phase regime during the dynamic simulation. It can therefore be used for comprehensive simulation of, e.g., distillation columns, where the number of phases present can change during startup and shutdown. The nonsmooth model is illustrated through examples of an evaporator and a distillation column. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3334–3351, 2016  相似文献   
85.
Sir:

A Fortran IV computer program is used to calculate absorbance at varying wavelengths in a UV-visible rapid scanning spectrophotometer. Using the program eliminates the necessity of calibrating the absorbance axis in the usual manner using standard solutions or filters and plotting calibration curves, because the voltage output of the computer is automatically identical to the actual absorbance of a sample.  相似文献   
86.
Monitoring the distribution of water content is essential for understanding hydrological processes in the lithosphere and the pedosphere. The movement of water in unsaturated rock formations and in the vadose zone is influenced by different processes (mainly infiltration, evaporation, percolation and capillary flow) which may be rate determining depending on the actual conditions. The interdependence of these processes also strongly influences the transport and distribution of solutes in the pore space. In order to gain a better understanding of the movement and distribution of water in unsaturated media, systematic investigations with non-invasive or minimal invasive methods appear to be most suitable. Studies on the distribution of electrical conductivity can improve risk analysis concerning waste disposals in general and nuclear waste repositories in particular. Induced polarization and magnetic flux density determined with two highly sensitive accessories yield additional information and may allow for better discrimination of coupled flow processes. Electrical impedance tomography (EIT) with 20 current injection and 48 voltage electrodes was used here to monitor the evaporation of tap water from a container filled with sand under laboratory conditions at 20 °C. The results are compared with data obtained by determining spectral induced polarization (SIP) of sand during desaturation in a multi-step outflow equipment. Infiltration processes and evaporation from sand saturated with 0.01 M CaCl2 were determined by magneto-electrical resistivity imaging technique (MERIT). The results were obtained from a long-term experiment under controlled conditions.  相似文献   
87.
Polyethylene pipes are commonly used in pipeline systems. Current methods used to determine the pipe pullout capacity do not consider the effects of diameter changes and cyclic movements that the pipelines may experience. Laboratory tests were performed to study the interface shearing resistance of polyethylene pipes under varying conditions. The tests were performed in a temperature-controlled room, where properties were investigated for thermal variations expected in the field. Two types of tests were performed: pull/push tests and cyclic tests. Test results indicated that reductions in pipe diameter affect the interface shear resistance that develops between the pipe and soil. As the pipe diameter gets smaller, the normal contact stresses at the interface decreases, causing a reduction in the interface shearing resistance directly proportional to the normal stress changes. Cyclic pipe movements also cause significant reduction in pipe pullout resistance. The test results indicated that the polyethylene pipe interface shear resistance can be significantly lower than the one determined using the current methods. This paper presents the test results, findings, and design recommendations for the pullout resistance of buried polyethylene pipes.  相似文献   
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