Dr. John L. Daniels, P.E., F.ASCE

Publications

Textbook

1. Fang, H.Y. and Daniels, J.L. 2006. Introductory Geotechnical Engineering: An Environmental Perspective, Taylor and Francis, Ltd ISBN: 0415304016 (hardback), ISBN: 0415304024 (paperback)

Journals
1. Mahedi, M., Satvati, S., Cetin, B., and Daniels, J.L. (2020) “Chemically Induced Soil Water Repellency and the Freeze-Thaw Durability of Soils”, ASCE Journal of Cold Regions Engineering, 34(3) pp. 1-7.
2. Zhang, Y., Daniels, J.L., Cetin, B., Baucom, I.K. (2020) “Effect of Temperature on pH, Conductivity, and Strength of Lime-Stabilized Soil” ASCE Journal of Materials in Civil Engineering Vol. 32 (3), pp. 1-12.
3. Feyyisa, J.L. and Daniels, J.L. (2019) “The role of ash mineralogy on breakthrough pressure and contact angle: a statistical evaluation” Coal Combustion and Gasification Products, Vol. 11, pp. 45-58
4. Feyyisa, J.L., Daniels, J.L., Pando, M.A., Ogunro, V.O. (2019) “Relationship between breakthrough pressure and contact angle for organo-silane treated coal fly ash” Environmental Technology and Innovation, 14, 1-20.
5. Daniels, J.L. and Das, G.P. (2018) “Influence of Flowrate on Leachability, Coal Combustion and Gasification Products” Vol. 10, pp. 34-40.
6. Keatts, M.I., Daniels, J.L., Langley, W.G., Pando, M.A. and Ogunro, V.O. (2018) “Apparent Contact Angle and Water Entry Head Measurements for Organo-Silane Modified Sand and Coal Fly Ash”, ASCE Journal of Geotechnical and Geoenvironmental Engineering 144 (6) 1-9.
7. Feyyisa, J.L., Daniels, J.L., and Pando, M.P. (2017) “Contact Angle Measurements for use in Specifying Organo-Silane Modified Coal Combustion Fly Ash, ASCE Journal of Materials in Civil Engineering, 29(9) 1-14.
8. Jordan, C.S., Daniels, J.L., Langley, W, (2017) “The Effects of Temperature and Wet-Dry Cycling on Water Repellent Soils”, Environmental Geotechnics, 4 (4), Institution of Civil Engineers Publishing, United Kingdom,
http://www.icevirtuallibrary.com/content/article/10.1680/envgeo.14.00032
9. Daniels, J.L. (2016) “Coal Ash and Groundwater: Past, Present and Future Implications of Regulation”. William & Mary Environmental Law and Policy Review, 40 (2), 535-555.
Wu, J., Tang, C., Gao, L., Jiang, H. and Daniels, J.L. (2014) “Effect of ground covers on soil temperature in urban and rural areas” Environmental and Engineering Geoscience 20 (3), 225-237.
10. Bowers, B.F., Daniels, J.L. and Anderson, J. B. (2014) “Field Considerations for Calcium Chloride Modification of Soil-cement” Journal of Materials in Civil Engineering 26 (1), 65-70.
11. Tang, Chao-Seng, Shi, B., Gao, L., Daniels, J.L, Jian, H-T. and Liu, C. (2011) “Urbanization effect on soil temperature in Nanjing, China” Journal of Energy and Buildings Energy and Buildings 43(11):3090-3098.
12. Lei, S., Bian, Z., Daniels, J.L., He, X. (2010) “Spatio-temporal variation of vegetation in an arid and vulnerable coal mining region” Mining Science and Technology, 20(3) 485-490
13. Bian, Z., Inyang, H.I., Daniels, J.L., Otto, F. and Struthers, S. (2010) “Environmental issues from coal mining and their solutions” Mining Science and Technology, 20(2) 215-223
14. Lei, S., Daniels, J.L., Bian, Z. and Wainaina, N. (2010) “Improved soil temperature modeling” Environmental Earth Science, 62(6), 1123-1130
15. Daniels, J.L., Wood, S.L. and Kemnitzer, S.C. (2011) “The role of NSF’s Department Level Reform program in engineering education practice and research” Advances in Engineering Education, 2(4), 1-15.
16. Daniels, J.L., Mehta, P., Vaden, M., Sweem, D., Mason, M.D. Zavareh, M. and Ogunro, V.O. (2009) “Nano-scale organo-silane applications in geotechnical and geoenvironmental engineering” Journal of Terraspace Science and Engineering 1(1): 21-30
17. Fang, H.Y. and Daniels, J.L. (2007) “Tyre Aggregate Applications in Geotechnical and Geoenvironmental Engineering” International Journal of Environment and Waste Management 1 (2/3), pp. 159-178
18. Daniels, J.L., Serrano, Hernandez, M.T.S., Das, G. and Bae, S. (2006) “Coastal pollution mitigation with lime and zero valent iron” Journal of Marine Georesources and Geotechnology, Special Issue on Taiwan Straits Tunnel (TST) Project, 24 (3), 183-191
19. Daniels, J.L. and Das, G.P. (2006) “Leaching Behavior of Lime-Fly Ash Mixtures” Journal of Environmental Engineering Science Vol. 23, No. 1, pp. 42-52
20. Daniels, J.L., Cherukuri, R., Hilger, H.A., Oliver, J.D. and Bin, S. (2005) “Engineering Behavior of Biofilm Amended Earthen Barriers Used in Waste Containment” Management of Environmental Quality, An International Journal, 16 (6), 691-704
21. Daniels, J.L. and Cherukuri, R. (2005) “The influence of biofilm on barrier material performance” ASCE Practice Periodical of Hazardous, Toxic and Radioactive Waste Management, 9 (4), 245-252
22. Daniels, J.L., Inyang, H.I. and Chien, C.C. (2004) “Verification of heavy metal sorption in soil-bentonite using SEM/EDXS” ASCE Journal of Environmental Engineering, 130 (8), 910-917
23. Daniels, J.L., Inyang, H.I. and Brochu, M. (2004) “Specific surface area of barrier mixtures at various outgas temperatures” ASCE Journal of Environmental Engineering, 130 (8), 867-872
24. Daniels, J.L. and Inyang, H.I. (2004) “Contaminant barrier material textural response to interaction with aqueous polymers” ASCE Journal Materials in Civil Engineering, 16 (3), 265-275
25. Fang, H.Y., Daniels, J.L. and Kim, T.H. (2004) “Pollution intrusion on soil-pavement system” ASCE Journal of Transportation Engineering” 130 (4), 526-534
26. Daniels, J.L., Inyang, H.I. and Iskandar, I. (2003) “Durability of Boston Blue Clay in waste containment applications” ASCE Journal of Materials in Civil Engineering, 15 (2), 144-152
27. Daniels, J.L., Chien, C.C., Ogunro, V.O. and Inyang, H.I. (2000) “A comparative analysis of contaminant migration models using barrier material data” Journal of Soil and Sediment Contamination 9 (5), 487-501

Peer-Reviewed Proceedings, Encyclopedia Articles, Book Chapters

1. Daniels J.L. (2020) Engineered Water Repellency for Applications in Environmental Geotechnology. In: Reddy K.R., Agnihotri A.K., Yukselen-Aksoy Y., Dubey B.K., Bansal A. (eds) Sustainable Environmental Geotechnics. Lecture Notes in Civil Engineering, vol 89. Springer, Cham. https://doi.org/10.1007/978-3-030-51350-4_6
2. Daniels, J.L. and Carriker, N.E. (2017) Chapter 19: Environmental Impact and Corrective Action, In: Coal Combustion Products (CCP’s): Characteristics, Utilization and Beneficiation, Robl, T., Jones, R., Oberlink, A., Editors, Elsevier.
3. Dumenu, L., Pando, M.A., Ogunro, V.O., Daniels, J.L., Moid, M.I. and Rodriguez, C. (2017) “Water Retention Characteristics of Compacted Coal Combustion Residuals”, Geotechnical Special Publication No. 276, pp. 403-413, ASCE, Reston, VA.
4. Feyyisa, J.L. and Daniels, J.L. (2016) “A Dynamic Contact Angle Measurement Technique for Water Repellent Coal Fly Ash (CFA),” Geotechnical Special Publication No. 271, pp. 925-938, ASCE Reston, VA.
5. Daniels, J.L. and Das, G. (2014) Practical Leachability and Sorption Considerations for Ash Management. Geo-Congress 2014 ASCE Reston/VA, pp. 362-376.
6. Lei, S., Daniels, J.L. and Bowers, B.F. (2013) “Tube suction test for evaluating moisture susceptibility resulting from calcium chloride” Geotechnical Practice Publication “Geomechanics and Transportation Geotechnology”, B. Huang, B.F. Bowers and G. Mei, Editors, ASCE Reston/VA, pp. 76-82.
7. Bowers, B.F., Daniels, J.L., Lei, S. and DeBlasis, N.J. (2013) “Additives for soil-cement stabilization” Geotechnical Practice Publication “Geomechanics and Transportation Geotechnology”, B. Huang, B.F. Bowers and G. Mei, Editors, ASCE Reston/VA pp. 68-75.
8. Daniels, J.L. (2012) “Science and Engineering Education: A Perspective from the U.S. National Science Foundation” Invited Paper for Special Volume dedicated to the 100th Jubilee of Madame Wu Chien-Shiung, Southeast University, Nanjing, China, G.C. Sih and A.Q. Li, Eds., pp. 81-107., Global Scientech Publishing Company, ISBN 978-0-615-57310-6
9. Daniels, J.L., Lei, S., Bian, Z. and Bowers, B.F. (2010) “Air-Soil Relationships for Lime and Cement Stabilized Subgrades” GeoShanghai, Geotechnical Special Publication, ASCE Reston/VA, Paving Materials and Pavement Analysis (GSP 203), pp. 341-346
10. Daniels, J.L., Janardhanam, R., Starnes, J., DeBlasis, N. and Miles, K (2009). “Cold-weather concreting technology for ground modification” Contemporary topics in ground modification, problem soils, and geo-support, (GSP 187) ASCE, Reston/VA 273-280
11. Daniels, J.L., Hourani, M.S. (2009). “Soil improvement with organo-silane” Advances in Ground Improvement, (GSP 188) ASCE Reston/VA: 217-224
12. Daniels, J.L., Cherukuri, R. and Ogunro, V.O. (2009) “Consolidation and Strength Characteristics of Biofilm Amended Barrier Soils” Appropriate Technologies for Environmental Protection in the Developing World; Yanful, Ernest K. (Ed.), Hardcover, ISBN: 978-1-4020-9138-4, pp. 265-279
13. Daniels, J.L. and Das, G.P. (2008) “Field scale characterization of coal combustion fly ash stabilized with lime and FGD gypsum” GeoCongress 2008: Geotechnics of Waste Management and Remediation (GSP 177), ASCE, Reston/VA: 684-691
14. Daniels, J.L. and Janardhanam, R. (2007). “Cold-weather subgrade stabilization” Soil Improvement, (GSP 172), ASCE, Reston/VA: 1-10
15. Nasipuri, A., Subramanian, K.R., Ogunro, V.O., Daniels, J.L. and Hilger, H.A. (2006). “Development of a wireless sensor network for monitoring a bioreactor landfill” ASCE Geo Congress 2006, February 26- March 1, 2006, Atlanta, GA, USA
16. Daniels, J.L., Schmader, M.B., Ogunro, V.O. and Hilger, H.H. (2005) “Laboratory-Scale Aerobic Landfill Bioreactor: A Precursor to Modeling and Full-Scale Investigation” In Geo-Frontiers 2005 (Geotechnical Special Publications 130-142 & GRI-18; Proceedings of the Geo-Frontiers 2005 Congress, January 24-26, 2005, Austin, Texas, CD-ROM, ISBN 078440769X)
17. Galvao, C.B., Daniels, J.L. and Inyang, H.I. (2004) Contaminated site characterization and monitoring, In: Environmental Monitoring, Theme 6.38 of the Encyclopedia of Life Support Systems, Daniels, J.L. and Inyang, H.I. Eds., United Nations Educational, Scientific and Cultural Organization
18. Daniels, J.L. and Bae, S-Y. (2004) Laboratory-based analytical technologies, In: Environmental Monitoring, Theme 6.38 of the Encyclopedia of Life Support Systems, Daniels, J.L. and Inyang, H.I. Eds., United Nations Educational, Scientific and Cultural Organization
19. Inyang, H.I., Daniels, J.L. and Chien, C.C. (2000) “Methods of analysis of contaminant migration in barrier materials” In: Remediation of Hazardous Waste Contaminated Soils, 2nd Edition, Wise et al., Eds., pp. 63-82
20. Inyang, H.I., Daniels, J.L. and Ogunro, V.O. (1998) “Engineering controls for risk reduction at Brownfield sites” Proceedings of ASCE GeoCongress, Oct. 18-21, 1998, Benson et al., Eds., Boston, MA, pp 229-252
21. Fang, H.Y., Daniels, J.L. and Inyang, H.I. (1997) “Enviro-geotechnical considerations in waste containment system design and analysis” Proceedings of the 1997 International Containment Technology Conference, St. Petersburg, FL, pp. 414-420

Other Significant Publications and Documents

1. Daniels, J.L., Ogunro, V.O., Pando, M.A., Dumenu, L., and Feyyisa, J.L. (2019) “Engineered water repellency: An evolving approach to infiltration control” World of Coal Ash Conference, St. Louis, MO, May 2019
2. Daniels, J.L. (2015) Coal and Sustainable Development, Proceedings of the International Conference on Infrastructure Development for Environmental Conservation and Sustenance (INDECS-15), Adhiyamaan College of Engineering, Hosur, India, October 28-30, 2015, pp. 16-20.
3. Daniels, J.L. (2014) “Lose it by using it, A plan for coal fly ash from the 33 ponds throughout North Carolina”, Featured Story, The Professional Engineer, The magazine of North Carolina engineering, Summer, 2014, pp. 6-12.
4. Daniels, J.L., Langley, W.G. (2013) “Groundwater modeling report: Monitoring wells MW-9, MW-10, MW-13, Riverbend Steam Station. Submitted to Duke Energy as part of their compliance with regulatory requirements set by the North Carolina Department of the Environment and Natural Resources, June 21, 2013.
5. Hattaway, J., Hardin, C.D. and Daniels, J.L. (2013) “Recommended Guidelines for the Use and Application of the Leaching Environmental Assessment Framework (LEAF) for Coal Combustion Residuals” World of Coal Ash Conference, Lexington, KY, April 22-25, 2013.
6. Daniels, J.L. (2012) Expert Witness Report, Headwaters Resources, Inc. v. Illinois Union Insurance Company et al. Case 2:09-cv-01079-DB
7. Daniels, J.L. (2011) “Coal and Sustainable Science Policy” Keynote Lecture Paper, Chongqing, China. The Sixth International Conference of International Center For Sustainability, Accountability, And Eco-Affordability of Large Structures (ICSAELS), October 11-15, 2011.
8. Hardin, C.D. and Daniels, J.L. (2011) “Preserving Structural Fill and Mine Reclamation as Acceptable Beneficial Reuse of CCRs” World of Coal Ash Conference, Denver, CO, May 9-12, 2011
9. Daniels, J.L., Hourani, M.S. and Harper, L.S. (2009) “Organo-silane chemistry: A water repellent technology for coal ash and soils” World of Coal Ash Conference, Lexington, KY, May 4-7, 2009 http://www.flyash.info/2009/025-daniels2009.pdf
10. Sanusi, O., Tempest, B., Ogunro, V.O., Gergely, J and Daniels, J.L. (2009) “Effect of unreacted hydroxyl ion on release of trace metals from geopolymer concrete” World of Coal Ash Conference, Lexington, KY, May 4-7, 2009
http://www.worldofcoalash.org/2009/ashpdf/a072-sanusi2009.pdf
11. Daniels, J.L. (2007) “Comments and Recommendations – Land Subsidence and Reclamation in Xuzhou and Huaibei, China”, a technical report prepared in response to a reconnaissance trip made to Xuzhou, Huaibei and Beijing, China, May 9–18, 2007
12. Daniels, J.L. and Das, G.P. (2007) “Site-Specific Distribution Coefficients for Preliminary Modeling Purposes” for 8th International Conference on Waste Management, Environmental Geotechnology and Global Sustainable Development, Ljubljana, SLOVENIA, August 28-30, 2007
http://www.srdit.si/gzo07/papers/62JLDaniels_FinalPaperGzO07.pdf
13. Daniels, J.L., Hill, M.E., Das, G.P. and Ogunro, V.O. (2006) “Influence of residence time on fly ash leachability: long-term implications” 23rd Annual International Pittsburgh Coal Conference, Pittsburgh, PA, USA, September 25-28, 2006
14. Ogunro, V.O. Ayoola, M.G., Inyang, H.I., Anderson, B.J. and Daniels, J.L. (2006) “On the geotechnical properties of coal combustion by-products under different stress conditions” 23rd Annual International Pittsburgh Coal Conference, Pittsburgh, PA, USA, September 25-28, 2006.
15. Daniels, J.L. and Nimmala, V.D. (2006) “Use of limestone as a low-cost additive for cadmium removal” International Conference on Infrastructure Development and the Environment, Abuja, Nigeria, September 10-15, 2006
16. Daniels, J.L., Taylor, G. and Hilger, H.A. (2006) “Shear strength of a landfill cover soil as a function of methane exposure and biofilm production” International Conference on Infrastructure Development and the Environment, Abuja, Nigeria, September 10-15, 2006.
17. Fang, H-Y. and Daniels, J.L. (2006) “New Generation Material System for Landfill Liners & Leachate Controlling Facilities” International Conference on Infrastructure Development and the Environment, Abuja, Nigeria, September 10-15, 2006
18. Daniels, J.L. and Das, G.P. (2005) “The need for field-relevant leachability mass transfer coefficients” 22nd Annual International Pittsburgh Coal Conference, Pittsburgh, PA, USA, September 12-15, 2005, pp. 1-10
19. Daniels, J.L. (2005) Compliance Demonstration Report – Revised (2-Layer, 3D) Groundwater Modeling, Addendum Report to S&ME, Inc., Charlotte, NC, Completed June 2005
20. Daniels, J.L. and Janardhanam, R. (2005) Subgrade Stabilization Alternatives – Technical Assistance Report to North Carolina Department of Transportation, Raleigh, NC, Completed 6/30/05
21. Daniels, J.L. (2005) Leachability Evaluation of Mixtures of FGD Material and Fly Ash, Technical Report to Duke Energy, Completed 7/8/05
22. Daniels, J.L. (2005) Site-Specific Distribution Coefficients (Kd Values) – Marshall Steam Station FGD Material Landfill, Completed 8/22/05
23. Daniels, J.L. (2005) Site-Specific Distribution Coefficients (Kd Values) – Belews Creek Steam Station FGD Material Landfill, Completed 8/22/05
24. Daniels, J.L. (2005) Compliance Demonstration Report – Liner System Comparison Groundwater Modeling, Addendum Report to S&ME, Inc., Charlotte, NC, Completed October 2005
25. Shi, B., Cai, Y., Inyang, H.I., Daniels, J.L. and Jiang, H.. (2004) “Determination of Expansive Soil Grades Using Fuzzy Method” Proceedings of the 7th International Symposium on Environmental Geotechnology and Global Sustainable Development, Helsinki, Finland June 8-10, 2004.
26. Daniels, J.L. (2004) Capillary Rise Assessment, Technical Report to Duke Energy, Completed 11/1/04
27. Daniels, J.L. (2004) Test pad evaluation of fly ash, lime and FGD gypsum mixtures, Addendum Report to Duke Energy, Charlotte, NC, Completed 4/19/04
28. Daniels, J.L. (2004) Craig Road Landfill – Laboratory Testing and Modeling, Technical Report to S&ME, Inc., Charlotte, NC, Completed 5/31/04
29. Daniels, J.L., Das, G.P. and Goins, R.J. (2003) “Heavy metal sorption characteristics of a flue gas desulfurization material” 20th Annual International Pittsburgh Coal Conference, Pittsburgh, PA, USA, September 15-19, 2003
30. Daniels, J.L. (2003) Test pad evaluation of fly ash, lime and FGD gypsum mixtures, Final Report to Duke Energy, Charlotte, NC, Completed 12/24/03
31. Daniels, J.L. (2003) Permeable reactive layers for trace metals attenuation, Final Report to Duke Energy, Charlotte, NC, Completed 12/24/03
32. Daniels, J.L. (2003) Feasibility of enhanced contaminant attenuation in subgrade soils at the Belews Creek Ash Landfill, Final Report to Duke Energy, Charlotte, NC, Completed 2/28/03
33. Daniels, J.L. (2003) Interactions between coal combustion ash and flue gas desulfurization sludge: Implications for innovative waste management, Final Report to Duke Energy, Charlotte, NC, Completed 2/28/03
34. Daniels, J.L. (2003) Review of lime-fly ash mixtures: Engineering and environmental implications, Final Report to Duke Energy, Charlotte, NC, Completed 8/21/03
35. Daniels, J.L., Inyang, H.I. and Ogunro, V.O. (2002) “A methodology for fractionation of contaminant volumes to barrier slices.” The 6th International Symposium on Environmental Geotechnology and Global Sustainable Development, Seoul, Korea, July 2-5, 2002, pp. 381-387.
36. Daniels, J.L., Inyang, H.I. and Kurup, P. (2002) “The influence of dissolved polymers on the properties of earthen barriers used in waste containment applications.” The 6th International Symposium on Environmental Geotechnology and Global Sustainable Development, Seoul, Korea, July 2-5, 2002, pp. 363-370
37. Daniels, J.L., Inyang, H.I. and Fang, H-Y. (2001) “Theoretical relationship for scaling freezing-induced damage in barrier systems under laboratory and field conditions” Proceedings of the International Symposium on Application of Natural Materials for Environmental Geotechnology, Tokyo, Japan, October 29-November 2, 2001, pp. 37-55.
38. Daniels, J.L., Inyang, H.I. Howe, G.S. and Ogunro, V.O. (1999) “Innovative use of triaxial cell permeameters for measuring the earthen barrier resistance to freeze-thaw degradation under field conditions” Proceedings of the International Symposium on High Altitude and Sensitive Ecological Environmental Geotechnology, Nanjing, PR China pp. 326-333.
39. Fang, H-Y., Work, D.V. and Daniels J.L. “Preliminary study of the solar-electromagnetic process for improvement of dredged fill in reclaimed land applications” Proceedings of the 4th International Symposium on Environmental Geotechnology and Global Sustainable Development, Danvers, MA, pp. 1146-1157.
40. Fang, H.Y., Daniels, J.L. and Work, D.V. “Soil contamination and decontamination mechanisms under wet-dry and freeze-thaw conditions” Proceedings of the 4th International Symposium on Environmental Geotechnology and Global Sustainable Development, Danvers, MA, pp. 1158-1171.
41. Inyang, H.I., Daniels, J.L., Parikh, J.M. and Howe, G.S. (1998) “Characterization of contaminant barrier materials” CEEST/007R-98, Center for Environmental Engineering, Science and Technology, University of Massachusetts, Lowell, MA 44 pp.
42. Inyang, H.I., Bruell, C.J., Parikh, J.M. and Daniels, J.L. (1998) “Batch sorption of heavy metals on additve-amended barrier materials” CEEST/008R-98, Center for Environmental Engineering, Science and Technology, University of Massachusetts, Lowell, MA 203 pp.
43. Inyang, H.I., Daniels, J.L. and Parikh, J.M. (1998) “Attenuation of heavy metals in densified columns of barrier materials” CEEST/009R-98, Center for Environmental Engineering, Science and Technology, University of Massachusetts, Lowell, MA 43 pp.
44. Daniels, J.L., Work, D.V., Fang, H.Y. and Inyang, H.I. (1998) “Remediation of contaminated sites by solar-electromagnetic wave process,” Proceedings of the 5th Annual Northeast Regional Student Environmental Conference, Lowell, MA, pp. 31-43.
45. Daniels, J.L. (1998) “Assessment of intrinsic bioremediation as a site treatment technique,” Proceedings of the 5th Annual Northeast Regional Student Environmental Conference, Lowell, MA, pp. 14-22.
46. Fang, H.Y., Inyang, H.I. and Daniels, J.L. 1997. “Physico-chemical determinants of hard soil and soft rock characteristics” Proceedings of the Symposium on Rock Mechanics, Chongqing, P.R. China, pp. 1-7.
47. Fang, H.Y., Daniels, J.L. and Inyang, H.I. (1997) “Failure mechanisms of landfill covers” Proceedings of GREEN 2, the 2nd International Green Symposium on Geotechnics and the Environment, Cracow, Poland, Sept. 8-11, 1997.
48. Daniels, J.L. (1996) “Laboratory study of the hydraulic conductivity of contaminated soil” Proceedings of the 4th Annual Northeast Regional Student Environmental Conference, Lowell, MA pp. 77-82.