Steinle-Darling, E., Zedda, M., Plumlee,
M.H., Ridgway, H.F. and M. Reinhard. 2007. Evaluating the impacts
of membrane type,
coating, fouling, chemical properties and water chemistry on reverse
osmosis rejection of seven
nitrosoalklyamines, including NDMA. Journal of Membrane
Science, in press.
|
| Rodriguez,
G., Buonora, S., Knoell, T.,
Phipps, D. and H. Ridgway. 2004. Rejection
of pharmaceuticals by reverse osmosis (RO) membranes:
quantitative
structure activity relationship (QSAR) analysis. Final
project report submitted to
the National Water Research Institute, NWRI Project No.
01-EC-002. |
| Ridgway,
H.F., Ishida, K., and D.
Phipps. Membrane
Improvement Using Molecular Modeling: Strategies for Modeling
Performance
and Fouling, Water Reuse and Desalination Conference, 25-27
Singapore,
International Desalination Association (2003). |
| Riley,
R. L., Lin, S.
W., Murphy, A.,
Wiater-Protas, I.
and H. F. Ridgway. 2002. Development of a New
Chlorine and Biofouling Resistant Polyamide Membrane. Final project
report submitted to the US Army, Report No. A273214.
|
Project Development Group, Orange County
Water District, Fountain Valley, California. 2002. Investigation of
chlorine tolerant thin-film composite reverse osmosis membranes.
Project report submitted to the California Energy Commission, Project
Task 2.4 B 1.
|
| R. L.
Riley; S. W.
Lin; A. Murphy; H. F. Ridgway; K. P. Ishida. 2001. Development of Improved
Membranes for ROWPU Spiral_Wound Elements. Final project report 13 Nov 1998-1 Mar
2001, Phase 2, U.S. Army Report Number A650093. |
| Knoell,
T., J. Safarik, T. Cormack, R.
Riley,
S.W. Lin and H. Ridgway. 2000. Biofouling potentials
of microporous polysulfone membranes containing a sulfonated
polyethersulfone - polyethersulfone block copolymer:
correlation of membrane surface properties
with bacterial attachment. Journal of Membrane
Science, 157,
117-138. |
| Campbell, P.,
Srinivasan, R., Knoell, T., Phipps, D.,
Ishida, K., Safarik, J., Cormack, T. and H. F. Ridgway. 1999. Quantitative structure
activity realtionship (QSAR) analysis of surfactants influencing
attachment of a Mycobacterium species to cellulose acetate and
polyamide reverse osmosis membranes. Biotechnol.
Bioengineering 64, 527-544. |
| Ridgway,
H. F., K. Ishida, G. Rodriguez,
J. Safarik,
T. Knoell and R. Bold. 1999. Biofouling
of Membranes:
Membrane Preparation, Characterization, and Analysis of Bacterial
Adhesion,
pp. 463-494. In Doyle, R. (Ed.), Methods
in
Enzymology: Biofilms, Academic Press, San Diego, CA. |
Mirpuri
R.G.,
Jones W.L., McFeters G.A., Ridgway H.F. 1997. Physiological stress in
batch cultures of Pseudomonas putida 54G during toluene degradation. J. Ind.
Microbiol.
& Biotechnol. 6, 406-13.
|
| Phipps, D., G.
Rodriguez
and H.F. Ridgway. 1999. Deconvolution
Fluorescence Microscopy for Observation and Analysis of Membrane
Biofilm
Architecture, pp. 178-194. In Doyle,
R.
(Ed.),
Methods in Enzymology: Biofilms, Academic Press, San Diego, CA. |
| Foght,
J.M., Westlake, W.S., Johnson,
W.M. and
H.F. Ridgway. 1996. Environmental
gasoline-utilizing
isolates
and clinical isolates of Pseudomonas aeruginosa are indistinguishable
by
chemotaxonomic and molecular techniques. Microbiology
142,
2333-2340. |
| Ridgway,
H. F., Molecular
Modeling
of Organics
Adsorption to Synthetic Polymer Membranes, Proc.
International
Membrane Science and Technology Conference, 12-14 November 1996,
Sydney,
Australia (1996). |
| Ridgway,
H. F. and H. C. Flemming.
1996. Membrane
Biofouling, pp 6.1-6.62, In: Water Treatment:
Membrane Processes, J. Mallevialle, P. E. Odendaal, and M. R. Weisner
(Eds.),
McGraw-Hill Publishers, New York. |
| Ishida,
K, Milstead, C.E., Ridgway, H.F.
and R.
L. Riley. 1995. Identification
and evaluation of biocides
for
ROWPU systems. Final project report submitted to U. S.
Army, USA
Tank and Automotive Command, Mobility Tech CTR, Fort Belvoir, VA. |
| Leddy,
M.B., Phipps, D.W. and H.F.
Ridgway.
1995. Catabolite-mediated
mutations in alternate toluene
degradative
pathways in Pseudomonas putida. J. Bacteriol. 177,
4713-4720. |
| Ball,
H.A., Reinhard, M., Orwin, E.,
Ridgway,
H.F. and D.W. Phipps. 1993. Factors
influencing the
anaerobic
biodegradation of gasoline hydrocarbons by groundwater bacteria at Seal
Beach, CA. Final project report No. SU89-15, U. S. Dept.
of the
Navy,
Environmental Protection Division, Code ESC411, Naval Facilities
Engineering
Service Center, Port Hueneme, CA. |
| Gersberg,
R.M., Dawsey, W.J. and H.F.
Ridgway.
1993. In-situ
microbial degradation of gasoline. Final
project
report No. RP-2795-2, Electric Power Research Institute. |
| Rodriguez,
G.G., Phipps, D., Ishiguro,
K. and
H.F. Ridgway. 1992. Use
of a fluorescent redox probe for
direct
visualization of actively respiring bacteria. Appl.
Environ.
Microbiol.
58, 1801-1808. |
| Schaule,
G., Flemming, H.-C. and H.F.
Ridgway.
1992. Use
of 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) for
quantifying
planktonic and sessile respiring bacteria in drinking water.
Appl.
Environ. Microbiol. 59, 3850-3857. |
| Ridgway,
H.F. and J. Safarik.
1991. Biofouling
of reverse osmosis membranes, pp. 81-111. In H.-C.
Flemming
and G.G. Geesey (Eds.), Biofouling and Biocorrosion in Industrial Water
Systems, Springer-Verlag, Berlin. |
| Ridgway,
H.F., Safarik, J., Phipps, D.,
Carl,
P. and D. Clark. 1990. Identification
and catabolic
activity
of well-derived gasoline-degrading bacteria from a contaminated
aquifer.
Appl. Environ. Microbiol. 56, 3565-3575. |
| Ridgway,
H.F., Phipps, D.W., Safarik,
J., Haag,
F., Reinhard, M., Ball, H., and P. L. McCarty. 1989. Investigation
of the transport and fate of gasoline hydrocarbon pollutants in
groundwater.
Final project report submitted to the U. S. Geological Survey; contract
grant No. 14-08-0001-G1126. |
| Ridgway,
H. F., Microbial
Adhesion
and Biofouling
of Reverse Osmosis Membranes, In Parekh, B. (Ed), Reverse
Osmosis
Technology: Application for High-Purity Water Production, Marcel
Dekker, Inc., New York and Basel (1988). |
| Ridgway,
H.F. and R.A. Lewin.
1988. Characterization
of gliding motility in Flexibacter polymorphus.
Cell Mot. Cytoskel. 11, 46-63. |
| Ridgway,
H.F. 1987. Microbial
fouling
of reverse osmosis membranes: genesis and control, pp.
138-193.
In M.W. Mittleman and G.G. Geesey (Eds.), Biological Fouling of
Industrial
Water Systems: A Problem Solving Approach, Water Micro Associates, San
Diego. |
| Ridgway,
H.F., Rogers, D.M. and D.G.
Argo.
1986. Biofilm
on reverse osmosis membranes. Water and Waste
Treatment 63, 45-48. |
| Ridgway,
H.F., Rigby, M.G. and D.G.
Argo.
1985. Bacterial
adhesion and fouling of reverse osmosis
membranes.
J. Amer. Water Works Assoc. 77, 97-106. |
| Ridgway,
H.F., Rigby, M.G. and D.G.
Argo.
1984. Adhesion
of a Mycobacterium sp. to cellulose diacetate
membranes
used in reverse osmosis. Appl. Environ. Microbiol. 47,
61-67. |
| Ridgway,
H.F., Justice, C.A., Whittaker,
C., Argo,
D. and B.H. Olson. 1984. Biofilm
fouling of RO
membranes:
its nature and effect on treatment of water for reuse. J.
Amer.
Water
Works Assoc. 76, 94-102. |
| Whittaker,
C., Ridgway, H.F. and B.H.
Olson.
1984. Evaluation
of cleaning strategies for removal of biofilm
from
reverse osmosis membranes. Appl. Environ. Microbiol. 48,
395-403. |
| Ridgway,
H.F., Justice, C., Kelly, A.
and B.H.
Olson. 1983. Microbial
fouling of reverse osmosis membranes
used in advanced wastewater treatment technology: chemical,
bacteriological,
and ultrastructural analyses. Appl. Environ.
Microbiol.
45,
1066-1084. |
| Ridgway,
H.F. and R.A. Lewin.
1983. Subunit
composition of goblet-shaped particles from the cell wall of
Flexibacter
polymorphus. Can. J. Microbiol. 29, 1689-1693. |
| Leong,
L.Y.C., Otsaka, D., Ridgway, H.F.
and B.H.
Olson. 1981. Chlorine
resistance of coliform-tested bacteria isolated
from
raw and treated sewage effluents. Prog. in Water Technol. |
| Ridgway,
H.F., Means, E.G. and B.H.
Olson.
1981. Iron
bacteria in drinking water distribution systems: elemental analysis of
Gallionella stalks using x-ray energy dispersive
microanalysis. Appl. Environ. Microbiol. 41, 288-297. |
| Means,
E.G., Hanami, L., Ridgway, H.F.
and B.H.
Olson. 1981. Enumeration
of bacteria in potable water
distribution
systems: evaluation of media and plating techniques.
J.
Amer.
Water Works Assoc. 73, 585-590. |
| Ridgway,
H.F. and B.H. Olson.
1981. Scanning
electron microscope evidence for bacterial colonization of a
drinking
water distribution system. Appl. Environ. Microbiol. 41,
274-287. |
| Simon,
M.I., Silverman, M., Matsumura,
P., Ridgway,
H., Komeda, Y. and M. Hilman. 1978. Structure
and function
of bacterial flagella. Symposia of the Society for General
Microbiology,
No. XXVIII, Relations Between Structure and Function in the Procaryotic
Cell, pp. 271-286. |
| Ridgway,
H.F. 1977. The
source of
energy for gliding motility in Flexibacter polymorphus: effects
of
metabolic and respiratory inhibitors on gliding movement.
J.
Bacteriol.
131, 544-556. |
| Ridgway,
H.F. 1977. Ultrastructural
characterization of goblet-shaped particles from the cell wall of
Flexibacter
polymorphus. Can. J. Microbiol. 23, 1201-1213. |
| Ridgway,
H.F., Silverman, M. and M.I.
Simon.
1977. Localization
of proteins controlling motility and
chemotaxis
in Escherichia coli. J. Bacteriol. 132, 657-665. |
| Ridgway,
H.F., Wagner, R.M., Dawsey,
W.T. and
R.A. Lewin. 1975. Fine
structure of the cell envelope
layers of Flexibacter polymorphus. Can. J.
Microbiol. 21,
1733-1750 |
| Ridgway,
H.F. and R.A. Lewin.
1973. Goblet-shaped
sub-units from the wall of a marine gliding
microbe.
J. Gen. Microbiol. 79, 119-128. |
Harry
Ridgway has
been
engaged
in the research and development of water purification membranes and
membrane
processes for more than two decades. From 1981 until 2002, Dr.
Ridgway served as the Research Director for the Orange
County Water District
(OCWD) in Fountain Valley, California, home of
Water
Factory 21, the world's first large-scale application of reverse
osmosis (RO) membrane technology for water reuse. While at OCWD,
Dr. Ridgway pioneered the development of novel methods for carrying out
detailed studies on the
mechanism
and dynamics of bacterial adhesion and biofilm formation on RO
membrane materials, a phenomenon known as membrane
biofouling. While membrane biofouling still remains a serious problem
in many membrane applications, the results of his early work helped
shape the current
generation of commercial low-fouling polyamide RO membrane
materials. More
recently, Dr. Ridgway has developed computer programs that enable molecular
modeling of novel crosslinked
polymer membrane materials. The computer programs facilitate
exploration of many theoretical
aspects of water
and solute transport through RO membrane materials. They
also
provide fresh insight into the mechanisms of foulant adsorption to
membrane surfaces. Dr.
Ridgway received a Bachelor of Science degree in Microbiology (and a
minor in
Chemistry)
in 1971 from San Diego State University and a PhD in Marine
Microbiology from Scripps
Institute
of Oceanography in 1976. His doctoral research focused on the
ultrastructural and biochemical basis of gliding motility in the
filamentous marine bacterium Flexibacter
polymorphus. From 1976 to 1978, Dr. Ridgway was a
postdoctoral research fellow at the University of California, San Diego
where he performed fundamental genetic and biochemical studies on the
mechanism of motility and chemotaxis in the bacterium Escherichia coli. From 1978
to 1981, Dr. Ridgway joined the University of California, Irvine where
he conducted additional postdoctoral studies on the microbiology of
drinking water distrubtion systems. It was during that period
that he became interested in the interaction of bacteria with RO
membrane materials. Dr. Ridgway currently holds a Consulting
Professorship with Stanford University in the Civil
and Environmental Engineering Department and in 2002 he was
awarded the Athalie
Richardson Irvine Clarke Prize for his pioneering
contributions
in the area of membrane biofouling. AquaMem
Scientific Consultants maintains active national and
international collaborations with several universities
and
government entities.