text: Event RCF amplifies the wake in memory of Padre Pio The TT+ High Definition Touring and Theatre has been chosen to amplify the wake in memory of Padre Pio that took place at the end of September in San Giovanni Rotondo (south of Italy). Thousands of peoples attended the church service gathered in the space around the Sanctuary. In order to have a perfect audio coverage RCF was involved to manage the audio project for the event. Ing. Emanuele Morlini, TT+ Product Specialist, made a preliminary simulation in order to verify the diffusion, the sound pressure level and speech intelligibility. The RCF system managed to perform very well delivering a wide and perfect sound for both music and speech. The RCF system was composed by: 32 TTL33-A Line Array Modules; 8 TTS28-A Subwoofers; 4 TT22-A speakers; 4 TT25-A speakers; 4 TT08-A Precision Monitor. Más información Installation St. Lawrence Martyr Enjoys Revival with RCF VSA (Edison, New Jersey) While celebrating a 150 year history, St. Lawrence Martyr in Maryland is also celebrating a spiritual revival the congregation has experienced in the most recent decade. New ministry management has fostered much of the spiritual growth through a Life Teen youth ministry, addition of Adult faith programs and including International Nights to a revitalized welcome ministry. That growth spurred a capital campaign in 2014 to build a new parish complex. On June 3, Baltimore Archibishop William Lori presided over a Dedication Mass blessing the new facility. When facility design was in the planning stages, Michael Klass of Baltimore-based Klassic Sound was referred to provide a solution for their sanctuary sound. Más información Event RCF Boosts Fan Experience at Bridgestone Arena For the first time in 20 years an NHL hockey team has won all their consecutive NHL home games during the playoffs. That team – the Nashville Predators. The venue – Bridgestone Arena. The excitement is building for the team, and much of it is being related to the fan experience at the facility. "AV is an integral part of that experience," notes the arena's Senior Director of Technical Operations Ben Bosse. "More than integral, it is an essential item," attributing the music and video as a big part of the "total game experience" relating both pre-game and post-game productions and inciting the crowd during in-game breaks in the action. According to an ESPN Ultimate Standings fan survey from this past fall, "The Bridgestone Arena topped the charts in stadium experience, and it seems like it will only continue to improve," as management had already announced plans to improve the arena. Into the mix comes Durrell Sports, a Nashville-based sports stadium consultant. "Bridgestone has always been a home town favorite to our company," says Durrell principal John Horrell. "We have been connected to them, as being their main sound consultant, lessor of audio equipment, provider of Media Services and supplied audio technicians for the past twelve years. Watching the success of the building (rated in the top five most used stadiums in the country 10 years running) and the success of the Predators team have been exciting to say the least." Durrell was involved with the selection of the original system 12 years ago. Recognizing that system was showing its age and in need of repairs, and with the commitment from the facility management for needed upgrades, Horrell started to explore new solutions. Más información Installation ORIGINAL BIERKELLERS OOMPAH A TRAVÉS DE RCF $dataLeanFields_separator.text_container.text.getData() Más información Installation Polygone Equipement reinforces Lille-Métropole Stadium for three-day event Full audio visual service company, Polygone Equipement, were recently brought in to provide auxiliary sound reinforcement for the prestigious European Athletics Team Championships at the 18,000-seat capacity Lille-Métropole Stadium. Formed in 1994, Polygone Equipement has been an RCF partner for most of that time, and working on the event for the first time they had no hesitation in picking a combination of high premium TTL33-A active line array and HDL20-A, RCF's popular and huge selling composite system to supplement the stadium PA. They used 12 of the TTL33-A, supported by eight elements of HDL20-A, underpinned with four TTS28-A subs, while a pair of TT25-A were detailed for monitoring purposes for the official speaker out on the central field. The TTL33-A's were arrayed in four main stacks, spaced around the stadium, each containing three enclosures plus a TTS28-A sub. Four additional stacks of dual HDL20-A line array modules were deployed with appropriate tilt angles for optimum coverage of the tribune seating. The FOH mixing console provided sources from CD players and jingles, while the five wireless mics offered long distance capability. All sound was processed through BSS Omnidrive and broadcast splits were sent to France Television for live transmission. According to the installation team the set-up had been straightforward because of the ground stacking design, while the RCF active line array solution proved a big advantage when it came to cabling issues. "The system sounded great, with plenty of power and perfect intelligibility and clarity," stated Polygone Equipement's Gerard Coucke. Más información Installation French Beach Rescue Centres turn to RCF horns for superior voice evac RCF partners, Dipsonic, have equipped a number of beach rescue centres on the north coast of France with HD6045EN fibreglass long-throw multicell horns, which are designed to withstand the most adverse weather conditions. Le Touquet-Paris-Plage is the highest profile resort to receive the rescue voice application but others nearby include Stella Plage, Merlimont Plage and Sainte-Cécile Plage. The work was commissioned by Citeos, VINCI Energies' Lighting and Urban Equipment brand, and the RCF solution was specified by M. Lefebvre from locally-based Dipsonic. His selection was based on the fact that the HD6045EN, rated at 133dB@1m, offered the highest SPL available for such a horn enclosure. In terms of design, two of these horns are pole-mounted and set side by side in a 'V' configuration, facing out in front of the central beach. At Sainte-Cécile they are directly fixed on the Rescue Centre wall itself. At Le Touquet-Paris-Plage an additional 25 RCF HD3216/T compact, lightweight and watertight horn speakers, will complete the installation along the 500-metre long sea wall, to increase the paging coverage at medium throw distance. The horns are powered from RCF's UP 8000 series amplifiers, suitable for 70V/100V applications via the PR4093 9-in/3-out pre-amp, which has been purpose designed to provide a flexible solution for paging and music application in PA systems of this nature. All the RCF Resort Centre installations have replaced previous voice evacuation systems. Más información Event RCF HDL 50-A boosts Alan Parsons Live Project Germany Alan Parsons and his band were back in Germany for 13 dates throughout the country in May. Más información Event RCF Audio Academy sounds good in Trinidad and Tobago $dataLeanFields_separator.text_container.text.getData() Más información Corporate Come to visit RCF at Infocomm, Orlando 14-16 June Booth 6953 During Infocomm, RCF will showcase its latest innovations in sound reproduction and amplification. The RCF's new product line will feature improvements, design upgrades and exciting new technologies, like the new FiRPHASE processing, on-board on an extended range of loudspeakers. Follow RCF on Facebook, Twitter and Instagram and don't miss the occasion to attend our product demos as shown below. HDL 6-A DEMOS Daily June 14-16 Demo Room W230A 9:00 - 10:00 a.m. 11:00 - 12:00 a.m. 01:00 - 02:00 p.m. 03:00 - 04:00 p.m. RCF's big-selling HD-Line series, spearheaded by the HDL 20-A, welcomes the RCF HDL 6-A: an ultra-compact bi-amped 2-way active touring system for small to medium events, both indoors and outdoors. Despite the size and the ultralight-weight, the playback clarity is incredible, thanks to the built-in 1400W, 2-way class-D amplifiers and the FiRPHASE DSP processing. DON'T MISS THE CHANCE TO VISIT US AND DISCOVER OUR ENTIRE PRODUCTS RANGE! BOOTH 6953 June 14-16 Orlando, FL Más información Installation DUTCH HOCKEY STADIUM upgrades with RCF P-SERIES Hockeycomplex 'Oosterplas', Hertogenbosch (Netherlands)- The field hockey club which is also known as HC Den Bosch, recently underwent a complete new sound system installation, turning to RCF for the solution. RCF's weatherproof IP55-rated P-series is no stranger to stadia and arenas throughout the world and has frequently been the architectural choice both for indoor installations in tough environments as well as outdoor applications such as stadiums and arenas. With three sides of the field open, all 20 of the P 3115-T, run 100V line, are distributed evenly along the roof of the single tribune, which also includes a central cluster. The full range, wide-dispersion, coaxial two-way loudspeaker system provides substantial power and efficiency. The HF section is a constant directivity CMD horn loaded to a 1" RCF Precision compression driver with a 1.5" diaphragm assembly. The LF transducer is a 15" woofer with 2.5" voice coil and the selectable line transformer makes is suitable for 70-100 volt applications. Commenting on the installation, Henri van Bergen, of RCF Netherlands, stated: "The most important consideration in stadiums like these is the Speech Transmission Index (STI), as well as fact the that the system must also sound great with music. "The client realised, during the final stages of decision making, that the RCF P-series gave them the best of both worlds." Más información Página 15 de 51 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 — 10 Items per Page Mostrando el intervalo 141 - 150 de 509 resultados. ← Primero Anterior Siguiente Último →


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There's nothing better than a fully fledged time machine. And we expect big things from the super-cerebral-time-traveling-mobster-shoot-em-up flick Looper. The early reviews for Rian Johnson's picture have been resoundingly positive, but there's still very little informatoin about the film in particular — until now. Take a look at the awesome-looking time device from Looper.
Released from Looper's Tumblr Account this is the "iron monstrosity with a hatch" as it was described previously on Bleeding Cool.
Alas, we still have a long ways to go — Looper won't be released until September 28th, 2012.

subset: commoncrawl


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Scenes from the New Jersey Wine & Food Festival, featuring Thomas Keller
This weekend, New Jersey's Crystal Springs resort hosted a benefit for the James Beard and Bocuse D'Or Foundations. The benefit featured a a grand tasting party with bites from Per Se, Osteria Morini, Maialino, and more—with everything from salmon tartar to homemade rhubarb dippin' dots.
I arrived early and was also able to catch an event on classic cocktails, a tasting that paired Valrhona chocolates with wine, and a tour of the resort's incredible wine cellar, which houses over 135,000 bottles (some over 100 years old). Click the slideshow above to see my favorite sips, bites, and chef sightings from the grand tasting, as well as other scenes from the festival's programs.
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Sens' Jean-Gabriel Pageau gets hat trick in fight-filled win over Habs
OTTAWA -- After getting his first NHL hat trick, Jean-Gabriel Pageau was left with a bloody smile after the Senators' Game 3 victory over the Montreal Canadiens on Sunday night.
The 20-year-old rookie lost a tooth in a fight-filled, emotional 6-1 win.
The teams combined for 236 penalty minutes and nine players were given a game misconduct.
The Senators have a 2-1 lead in the best-of-seven series and Game 4 is Tuesday night in Ottawa.
Pageau, with his first career playoff goal, gave the Senators a 2-1 lead early in the second as he slipped between defensemen P.K. Subban and Andrei Markov to beat Carey Price over the shoulder.
Pageau is not likely to forget the score as he was hit in the mouth by Subban on the goal and lost a tooth. Players could be seen looking for the tooth on the ensuing goal celebration.
"I might put it under my pillow and see what happens," Pageau kidded.
The crowd at Scotiabank Place chanted Pageau's name and the Ottawa native says he's hopeful to give them the opportunity to do it again.
"It was good motivation and forced me to push myself to keep going," Pageau said. "They liked my game and I didn't want to disappoint them after that."
The third period started with the Senators leading 2-1.
But after Pageau's second goal of the game and a Kyle Turris score made it 4-1, emotions overflowed and a line brawl broke out at center ice.
Turris' goal, his first of the series, at 7:00 put the game out of reach. On the ensuing faceoff, five different fights broke out.
"I thought we handled ourselves well under the circumstances and the duress we were put under and we defended ourselves," Ottawa coach Paul MacLean said.
The Senators ended up with the man advantage after the brawl and Jakob Silfverberg scored on the power play as he beat Price up high to make it 5-1 only 8 seconds after Turris' goal.
More penalties were taken, and at one point, Ottawa was left with just five players on the bench, while Montreal had six.
Ottawa's veteran forward Daniel Alfredsson finished the game playing defense.
After the game, Montreal coach Michel Therien took exception with MacLean calling a timeout with 17 seconds remaining.
In Therien's opinion MacLean was trying to embarrass and humiliate the Canadiens.
"As far as I'm concerned that was classless," Therien said.
With so few players on his bench and things already out of hand, MacLean felt he had no other option than to call a timeout to get his message to his players.
"I didn't want anyone to get hurt, it was already getting dumb enough as it was," MacLean said. "I have two important players on my team and I still have games to play. We're not giving them a freebie. There's already enough of that."
MacLean went on to say that he was protecting his players and he would do it again.
This is the second time Therien has taken issue with MacLean.
"I don't like when a coach is making comments," Therien said. "I don't like a coach when trying to humiliate our team. I don't like that."
MacLean wasn't impressed by the actions of the Canadiens and is hopeful the league will review certain aspects of the game, including Josh Gorges shooting the puck at Turris at the end of the game.
Pageau completed the hat trick, becoming just the second player in Senators history to get a hat trick in the playoffs with less than two minutes remaining. Alfredsson also did it in 1998.
Less than a month ago, Pageau was playing in the AHL. But his strong play has earned him the confidence of MacLean.
"It was a great night for the kid," MacLean said. "He's come in and played very, very well for us. We're really pleased for him, he's been a good player."
"He played a great game," Alfredsson said. "He had some great shots, picked the corners and it was fun for him."
Alfredsson scored Ottawa's opening goal and Craig Anderson stopped 33 shots.
Price faced 30 shots. Rene Bourque scored for the Canadiens at 14:34 of the first.
Captain Brian Gionta and Max Pacioretty, who both missed Game 2, were back in the lineup for the Canadiens.
The Canadiens had a couple of great chances to tie the game in the second, but came up short.
Alex Galchenyuk was stopped by Anderson as he came racing in alone. And then with Montreal on the power play, Tomas Plekanec rang a shot off the crossbar.
The Canadiens weren't pleased with their overall effort and know they need a better game plan looking ahead to Game 4 on Tuesday.
"Our problem was we tried to make plays that weren't there," Gorges said. "We weren't in our structure, we weren't in our system and when we're not we're chaotic.
"We knew they were going to come hard, we just didn't play a good fundamental game."
A physical first period ended with the teams tied 1-1.
The Senators made the most of a 28-second two-man advantage as Alfredsson picked up his rebound at his feet and quickly rifled it past the right of Price. It was the Senators' first power-play goal of the series.
Montreal tied the game with a power-play goal as Plekanec found Bourque to create a 2-on-1 break.
Bourque's shot changed speed and seemed to throw off Anderson and he was unable to get over in time and he could only watch as the puck trickle across the goal line.
Game notes
The Senators are without C Jason Spezza (back, indefinitely). D Eric Gryba served the second and final game of his suspension for his hit on Lars Eller in Game 1. Guillaume Latendresse and Andre Benoit were healthy scratches for the Senators in favor of Cory Conacher and Patrick Wiercioch. With Pacioretty and Gionta back in the lineup, Jeff Halpern and Gabriel Dumont were scratched for the Canadiens.


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Monthly Archive for November, 2012
Longer, healthier living
After examining what some believe leads to longer and healthier living, here are at least eight approaches I have found:
Fasting, Castration
A Mediterranean-style diet, Faith in God
Wild women and whiskey, Location and income
Being married, A positive outlook
Perhaps you have experimented with one or more of these? I've tried several. I'll let you guess which ones.
The wide variety of these contradictory theories reveals the sweeping net society is casting in its search for lasting health. The theories also indicate an abundance of misinformation and fears about aging.…


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Export 79 results:Author [ Title] Type Year
Filters: Author is Jayant A. Sathaye [Clear All Filters]
"Economic Analysis of Ilumex a Project to Promote Energy-Efficient Residential Lighting in Mexico." Energy Policy 22.2 (1994) 163 - 171. LBL-34877 Preprint..
Eliminating Electricity Deficit through Energy Efficiency in India: An Evaluation of Aggregate Economic and Carbon Benefits. 2010. LBNL-3381E..
"Emissions Scenarios, Costs, and Implementation Considerations of REDD Programs." Environment and Development Economics (2011). LBNL-5009E..
Empirical support for global integrated assessment modeling: Productivity trends and technological change in developing countries' agriculture and electric power sectors. Vol. 8. 2000. LBNL-56192..
Energy Demand in Asian Countries:. LBNL, 1986. LBL-21803..
"Energy Efficiency Improvements Potential in the U.S. Petroleum Refining Industry." 2014 ECEEE Summer Study on Energy Efficiency in Industry 2014. LBNL-6292E..
Energy Efficiency Indicators Methodology Booklet. 2010. LBNL-3702E..
Energy Use in Cities of the Developing Countries: A Review. LBNL, 1987. LBL-19597..
Estimating Carbon Dioxide Emissions Factors for the California Electric Power Sector. Berkeley: LBNL, 2002. LBNL-49945..
Estimating carbon dioxide emissions factors for the California electric power sector. Vol. 33. 2002. LBNL-49945..
Estimating Carbon Emissions Avoided by Electricity Generation and Efficiency Projects: A Standardized Method (MAGPWR). Berkeley, CA: Lawrence Berkeley National Laboratory, 2000. LBNL-46063..
Estimating energy-augmenting technological change in developing country industries. 2006. LBNL-55305..
Estimating Risk to California Energy Infrastructure From Projected Climate Change. 2011. LBNL-4967E..
Estimating the greenhouse gas benefits of forestry projects: A Costa Rican Case Study. Vol. 8. 2000. LBNL-42289..
"Forestry mitigation potential and costs in developing countries - Preface." Mitigation and Adaptation Strategies for Global Change 6 (2001). LBNL-50947..
Generalized Comprehensive Mitigation Assessment Process (GCOMAP):. LBNL, 2005. LBNL-55743..
GHG Mitigation Potential, Costs and Benefits in Global Forests: A Dynamic Partial Equilibrium Approach. 2006. LBNL-58291..
Greenhouse Gas Mitigation Options in ISEEM Global Energy Model: 2010-2050 Scenario Analysis for Least-Cost Carbon Reduction in Iron and Steel Sector. 2013. LBNL-6550E..
Guidelines for Monitoring, Evaluation, Reporting, Verification, and Certification of Energy Efficiency Projects for Climate Change Mitigation. 1999. LBNL-41543..
Implementing End-use Efficiency Improvements in India: Drawing from Experience in the US and Other Countries. USAID|INDIA, 2006. LBNL-60035..
India Energy Outlook: End Use Demand in India to 2020. LBNL, 2009. LBNL-1751E..
India's Aluminum Industry: Productivity, Energy Efficiency and Carbon Emissions. Vol. 4. 1999. LBNL-41845..


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The Bieber is turning seventeen on March 1 and I guess his wishes do not include a yakima bike rack or any other big boy toys. Instead, he expressed that he just wants to eat his grandmother's homemade cherry cheesecake with his family. He also said that he just wants to rest for a few days before his world tour kicks off in England on March 4. Simple requests from an international singing sensation, I say not bad huh? :)
Justin Bieber's Birthday
Saturday, February 26, 2011
Posted by Kaje at 03:28 0 comments
Coke Open Happiness
This video was shared in FB by a friend. Watch how happy the people were when they got their respective surprise gifts. This video actually made me smile :) Some people mentioned in the comments that the reactions were normal. They said to bring the truck even in a first world country, in a part where there is poverty and you will get the same reaction. Well, I beg to disagree because Pinoys are a appreciative bunch. I will bet that if you bring this truck in upscale Makati and you will surely make people smile with the ransom gifts, KWIM?
Anyway I also found it too funny that even without instructions, they figured it out just by touching that big "PUSH" button. Asahan mo na papakialaman ng Pinoy yan, LOL!
Posted by Kaje at 03:23 0 comments
Yakimix, Yet Again.
Friday, February 25, 2011
When my friend mentioned about them going to Yakimix for lunch, I said I wanted to eat there again. She suggested that we go to lunch at Yakimix Macapagal after booking our rooms at the travel fair. Such a perfect plan, I thought. We had delays during the booking, that we got to Yakimix after 12nn already. As expected, the place was already full and we had to wait. We were eleventh in line! I was losing hope already as I did not eat anything for breakfast and it seemed forever for a table to be ready. But before 1pm, we were already seated and I started to choose food from the buffet :) No talks of diet pills as we were all busy stuffing our stomachs, hehe.
Eating at Yakimix has always been a gastronomic experience. To date, I have already tried eating in their Morato, Trinoma and Macapagal branches. I feel most at home in Trinoma. I am sure there will be more Yakimix trips this year :)
Posted by Kaje at 14:16 0 comments
iPad 2!!
Guess what is getting launched on March 2?
Not that I have the budget to buy one when units start to sell in stores, but I am waiting for this since last year. I have been bugging the husband to buy me the iPad, but he agreed with my brothers to just wait for the second generation to arrive. The arrival is imminent and I find that I cannot concentrate anymore because I have started to day dream about it again.
The new iPad is expected to be thinner than its predecessor, with front facing camera, better display features and Face Time chat support. I have not read the rest of the spoilers, though.
Oh iPad, why are you so elusive!
Posted by Kaje at 14:09 0 comments
WTG, Maria!
Have you seen this video of Maria?
The 10 year old girl, looks and sounds Filipina because she is. Her parents are both from the Philippines but they are now based in Canada. One can never miss a Filipino talent, I must say. Last I heard, The Lady Gaga already invited her to sing duet in a Toronto concert. Maria was crying when she heard of the invitation. Who would not get overwhelmed by such, eh?
Posted by Kaje at 13:46 0 comments
Investing? Buy Gold Krugerrands!
If you choose to Buy Gold Krugerrands, you must know first that Krugerrand is a South African gold coin. It was first minted in 1967 and was actually intended to be circulated as a currency, thus it is made of more durable gold alloy not like most bullion coins in the market today. During the 70s and 80's it was illegal to import this king of coin in many Western countries but the ban ended in 1994 when the apartheid was abandoned. Krugerrand was once mass produced that by 1980, 90% of the gold coin market is composed of this kind. The US Gold Bureau being the leading dealer of gold and silver coins offer this kind to its clients.
Posted by Kaje at 13:35 1 comments
Lunch with Friends
Last Sunday, the meet-up with friends pushed through. Ane decided to stay home with K, so I had to drive all the way to Pasay, alone. It was okay, since I was able to accomplish what I went there for, which is to book our Boracay rooms and have lunch with some of the Bebots. The last I have seen the ladies was in November. Of course it was another day yet full of laughter, stories and worries. We talked about our children, our upcoming trip, and even things like pimples. See, M has acne breakout so I thought of sending her the link to the proactive review that I read somewhere. Anyway, we thought of spending more time together over coffee but being too full from our lunch at Yakimix, we just decided to go on our separate ways afterwards.
I always feel blessed to be with those ladies (and their families), they are now real friends even if we all just met online.
Posted by Kaje at 13:24 0 comments
Something Borrowed
Tuesday, February 22, 2011
There is a movie that I am so excited about – Something Borrowed. I saw the trailer last week and found out that this movie based on the book written by Emily Giffin will be shown in May. I really hope it will be shown around the same time here in Manila.
Anyway, I really hope the husband will go watch it with me when it starts showing :) I cannot wait to see whether they stayed true to the book or they veered away from it for cinematic purposes.
Here's the trailer:
Posted by Kaje at 13:13 0 comments
Looking Forward to Lunch Date
Saturday, February 19, 2011
Booking our accommodations at the travel fair is not the only thing that I am looking forward tomorrow. I mentioned that we will just go, book and leave the fair venue because we are having lunch together at Yakimix! Woohoo! I think Zanne and one of their friends are also joining us, but not sure. Yes, in the midst of trying to lose weight, we are going for buffet lunch, LOL! I am not sure which supplements I will be needing: the one to tame my cholesterol levels or the one to manage my weight. One thing's for sure, I am going to enjoy every minute because it is not always that I am able to have a peaceful lunch :)
Posted by Kaje at 14:40 1 comments
Artsy Marriage Proposal
While I was browsing for swimsuit inspirations, I got sidetracked by this video I found online:
PROPOSAL from Vanden on Vimeo.I am such a sucker for stuff like this! I was kind of teary eyed when he finally dropped on one of his knees and asked her!
Via woostercollective, the guy, "Aaron Vandenbroucke proposal to his girlfriend Tamara Marie Altherr included the participation of lots of street artists to create a secret street art "tour" leading up to the final piece where we popped the question."
So sweet and creative!
Posted by Kaje at 14:34 0 comments
Is it Possible?
I suddenly felt panic creeping into me when I realized that our beach trip is just less than three weeks away! I am looking forward to this trip because 1) it's just the three of us flying together, and 2) we are meeting 2 of my friends and their families there too! But you know me, somewhere along the way, I'm surely worrying abut something. On top of my hunt for the perfect pairs of swimwear, I am thinking how to lose belly fat fast before the trip if I want to feel good in those suits! I've already lost a few pounds for cutting down on soda and rice but the tummy remains my problem area. I.can.do.this.
Posted by Kaje at 14:20 0 comments
Travel Fair
I never thought that I would go to one, but I will tomorrow. I am meeting Mai and Kathy there :)
Since this already started yesterday, I have heard of good deals that I am dying to buy. But we are only going because that is the only way we can get discounts with our Boracay Accommodations. Talk about 20% discount on cash bookings. Not bad, huh, considering that we are staying for three nights and we are saving at least p3k if we book during the travel fair.
To avoid getting lured by the other offers, we decided to just go, book our rooms and leave the fair. No more window shopping for other offers if we don't want to spend on unplanned trips :)
I am actually starting to get excited about this trip!
Posted by Kaje at 14:14 0 comments
His Birthday Wish
Friday, February 11, 2011
My brother's birthday is coming up. We have no plans yet but I heard him say he wants to invite friends over for dinner and drinks. Maybe that's what we will do. As for gifts, I still do not know what I'll give him, I don't even have plans to give him anything because we're saving up for something. But I do know he would love to get a blackberry phone because his phone is just a pretty basic one. I am sure he would appreciate receiving one…from mommy! LOL! :)
Posted by Kaje at 02:57 0 comments
We're Back!
Tuesday, February 08, 2011
We actually flew back in early Saturday morning. We all had a blast in Singapore and I was so tired when we got back (which is kind of expected). I was hoping the luggage would fix themselves, but of course they didn't. I can only wish I have Harry Potter's wand, LOL! Anyway, I've been trying to regain my energy while doing things that need to be done in between.
Posted by Kaje at 14:02 0 comments
Widen your Vocabulary with these Beautiful and Ugly Words
I am amazed by the English language. I love that there are a lot of synonyms to make writing better and more artistic. But I still go for using words that you actually know the meaning of, not using them for the sake of showing off. I am all for widening the vocabulary, of course. This I probably got from my Grammar 101 teacher in high school :)
Here is a list of beautiful and ugly words to add to my and your vocabulary:
Beautiful Words
Amorphous: indefinite, shapeless
Beguile: deceive
Caprice: impulse
Cascade: steep waterfall
Cashmere: fine, delicate wool
Chrysalis: protective covering
Cinnamon: an aromatic spice; its soft brown color
Coalesce: unite, or fuse
Crepuscular: dim, or twilit
Crystalline: clear, or sparkling
Desultory: half-hearted, meandering
Diaphanous: gauzy
Dulcet: sweet
Ebullient: enthusiastic
Effervescent: bubbly
Elision: omission
Enchanted: charmed
Encompass: surround
Enrapture: delighted
Ephemeral: fleeting
Epiphany: revelation
Epitome: embodiment of the ideal
Ethereal: celestial, unworldly, immaterial
Etiquette: proper conduct
Evanescent: fleeting
Evocative: suggestive
Exuberant: abundant, unrestrained, outsize
Felicity: happiness, pleasantness
Filament: thread, strand
Halcyon: care-free
Idyllic: contentedly pleasing
Incorporeal: without form
Incandescent: glowing, radiant, brilliant, zealous
Ineffable: indescribable, unspeakable
Inexorable: relentless
Insouciance: nonchalance
Iridescent: luster
Languid: slow, listless
Lassitude: fatigue
Lilt: cheerful or buoyant song or movement
Lithe: flexible, graceful
Lullaby: soothing song
Luminescence: dim chemical or organic light
Mellifluous: smooth, sweet
Mist: cloudy moisture, or similar literal or virtual obstacle
Murmur: soothing sound
Myriad: great number
Nebulous: indistinct
Opulent: ostentatious
Penumbra: shade, shroud, fringe
Plethora: abundance
Quiescent: peaceful
Quintessential: most purely representative or typical
Radiant: glowing
Redolent: aromatic, evocative
Resonant: echoing, evocative
Resplendent: shining
Rhapsodic: intensely emotional
Sapphire: rich, deep bluish purple
Scintilla: trace
Serendipitous: chance
Serene: peaceful
Somnolent: drowsy, sleep inducing
Sonorous: loud, impressive, imposing
Spherical: ball-like, globular
Sublime: exalted, transcendent
Succulent: juicy, tasty, rich
Suffuse: flushed, full
Susurration: whispering
Symphony: harmonious assemblage
Talisman: charm, magical device
Tessellated: checkered in pattern
Tranquility: peacefulness
Vestige: trace
Zenith: highest point
Ugly Words
Cacophony: confused noise
Cataclysm: flood, catastrophe, upheaval
Chafe: irritate, abrade
Coarse: common, crude, rough, harsh
Cynical: distrustful, self-interested
Decrepit: worn-out, run-down
Disgust: aversion, distaste
Grimace: expression of disgust or pain
Grotesque: distorted, bizarre
Harangue: rant
Hirsute: hairy
Hoarse: harsh, grating
Leech: parasite,
Maladroit: clumsy
Mediocre: ordinary, of low quality
Obstreperous: noisy, unruly
Rancid: offensive, smelly
Repugnant: distasteful
Repulsive: disgusting
Shriek: sharp, screeching sound
Shrill: high-pitched sound
Shun: avoid, ostracize
Slaughter: butcher, carnage
Unctuous: smug, ingratiating
Visceral: crude, anatomically graphic
Posted by Kaje at 13:49 0 comments
Accutane Lawsuit
In recent years, there have been a number of complaints about Accutane. This medication was prescribed to cure cystic acne in the early 2000s. It seemed effective as I personally know someone who took this medicine as prescribed by her dermatologist. However, in 2006, a study was published saying that there is a link between the use of this drug and the increase in risk of contracting a inflammatory bowel disease. An Accutane lawsuit was actually settled and was awarded US$2.5 million in compensatory damages in 2007. Though Accutane have been pulled out of the market in 2009, there could be a lot more cases out there that needs attention. I suppose this could go on for years, and I just hope everyone who deserves to be compensated be given what is right for them.
Posted by Kaje at 13:02 1 comments


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I am an historic environment lead adviser for Natural England. Natural England is an executive non-departmental public body, sponsored by the Department for Environment, Food & Rural Affairs . We look after the natural environment including nature conservation (particularly SSSIs) and landscape – including cultural landscapes and the historic environment. We also work closely with the Environment Agency and Forestry Commission. I'm based in Yorkshire where I work with rural archaeological sites, traditional buildings and historic landscapes.
This year has been an interesting one for me as much of my work is involved with agri-environment schemes and this work has been affected by the Brexit vote. Some decisions have been delayed but we are all working hard to make up lost time and help our farmers with this year's grant applications which are due in for September. Natural England have also moved to a new delivery model where we have categorised our work into 'business as usual' and 'priority focus areas' – in these focus areas we will allocate added staff time to things like partnership working to achieve common objectives by working together with other organisations in the public and private sector. In Yorkshire and Northern Lincolnshire we have 9 focus areas and I work within 5 of these; Yorkshire Dales & Nidderdale, Humber, South Pennines, Dearne Valley, and Humberhead Levels while my colleague deals with archaeology in the other areas.
Today I am working from our head office in York (although I am usually based in Leeds with one day per week of home working and usually another out on various farms or nature reserves). I've got paperwork and email to catch up on as this has been a very busy week.
Some of this work relates to the Dearne Valley where there is a Heritage Lottery Funded Landscape Partnership. On Tuesday I went to a meeting at Elsecar Heritage Centre with the Dearne Valley Landscape Partnership and their new archaeological consultants. As part of Natural England's in-kind contribution to the project I helped to write the brief and assess tenders. This first meeting with the successful consultants, ArcHeritage, was to plan a series of events to involve the community within the Dearne Valley more closely with their heritage and inspire them to protect it. As the Dearne river valley has interesting mosaic habitats of wetland, woodland, farmland and restored coal tips it is an important wildlife refuge. It also has an amazing amount of archaeology, not just industrial – as you can see here in the Dearne Valley Heritage Audit.
Due to its habitat interest Natural England staff work a lot with farmers here, showing them how to manage their land sustainably, while my contribution is to help them manage their archaeological sites. Today I'm checking the sites that the consultants thought would be suitable for access and outreach activities to see if there are any clashes with our grant schemes, or if there are sensitive species which might mean that we need to alter our plans. So far I haven't found any major clashes! I'm confident that we can work together as a team to make the project work for nature, for the historic environment and for the local people but I can see from my maps that there are a few things which might have to be tweaked. I've contributed to a real reduction to heritage at risk in Yorkshire along with the farmers who manage the land and it's something I really do feel proud about.
The other big event this week was the reopening of Plumpton Rocks parkland. This Grade II* parkland was placed on the heritage at risk register in 2012 then in 2013 it applied for an agri-environment scheme. Along with the owner, Historic England and the Country Houses Foundation, Natural England have helped to grant aid a restoration including lake desilting, planting of new wood pasture (the planting plan being taken from historic OS mapping) and tackling of invasive species such as rhododendron and Himalayan balsam. While Natural England restored the landscape our partners have focused on the structural elements including the dam. It has been one of the trickiest restoration projects of my life (I usually have 6 or 7 medium to large restoration projects per year to deal with but this is a big one!) as there are lots of designations both for the historic structures and for the natural environment, all of which needed to be taken into consideration before we made any changes. I have been on the project steering group for the last 3 years so it was a big privilege for me to attend the reopening after so long making things happen behind the scenes. It's very unusual for us to be greeted by Betty's fat rascals and a glass of (non-alcoholic!) bubbly – and it'll all have to be reported on the central gifts register to ensure that I'm not being inappropriately influenced – but the owner really wanted to show his appreciation despite the rainy weather!
The work there will help local people see the parkland in its former glory, and I was simply busting with excitement to see how the press and local people would feel at the transformation. It was a little disappointing to have rain on such as special day although we braved the weather to walk around the lake and point out the transformation wrought by desilting, tree planting and felling and structural restoration. There are a few bits of restoration work still to complete but to see a neglected site transformed and teach owners how to care for their land long term is one of the best parts of my job. Today I'm writing up the experiences from this project so that other colleagues can learn from it as a case study and other sites will be able to benefit from my experiences. I'm also sending information about the press articles that are being written on the site to our communications officer and highlighting any tweets that we might want to retweet. Soon I will move on to another project but I do always feel a special connection to the places that I've been able to help.
Kat Hopwood-Lewis, BSc (Hons), MA, MCIfA


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Updated 3:38: Thanks to reader, Matt, for pointing out this BusinessInsider article titled: Marissa Mayer Bypassed As Google Appoints New Head Of Local And Commerce. Apparently Jeff Huber was handed the job and his title has been upgraded to SVP, Local and Commerce and is on par with the four mentioned below. It clarifies that local is a key initiative with visibility at the highest levels of Google. Not sure what is says about Marissa.
Read more: http://www.businessinsider.com/one-more-google-winner-jeff-huber-controls-commerce-and-local-2011-4#ixzz1Ixj2T8qZ
Larry Page took over as CEO of Google at the beginning of the week. Immediately thereafter, Google's product head Jonathan Rosenberg resigned.
Late Yesterday it was reported in an LA Time's exclusive that Page has completed a major reorganization at Google that put key executives in charge of their individual business units and reporting directly to him.
From the article (bolds mine):
Those promotions include Andy Rubin who is now senior vice president of mobile; Vic Gundotra who is now senior vice president of social; Sundar Pichai who is now senior vice president of Chrome; Salar Kamangar who is now senior vice president of YouTube and video; Alan Eustace, who is now senior vice president of search; and Susan Wojcicki, who is now senior vice president of ads.
The executives will be able to act more autonomously and won't have to turn to Google's powerful operating committee on every decision.
The structure certainly begs the question: Where's Local in all of this?
In mid October it was reported that Marissa Meyer had taken on a new role in charge of geo and local. More importantly it seemed, in being promoted to the operating committee it was noted that her voice and focus on local would be more widely heard. Now we learn that the operating committee will take on less of a product role and that Local, Geo and Maps are not in their own product category.
One presumes that Geo- Local will once again fall under the broad aegis of search and that Mayer will report to Alan Eustace. Although much of local is also social (Hotpot, Latitude). At least on the surface, it appears that Local (and perhaps Meyer) has been demoted. At best, it implies confused lines of authority.
Whether it will affect the investments necessary to take local to the next level is unclear. Whether decisions critical to local will be made quickly is also unclear.
Let's hope not.
I would love to hear your thoughts…Where Does Local Fit into the Newly Organized Google Under Page? by Mike Blumenthal


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Apartment industry benefits from foreclosures
New apartments being built to meet demand
Many homeowners are still struggling and facing foreclosures, and that is leading to a building boom of another kind in York.
York is undergoing an apartment boom with new apartments opening and being built.
Two apartment hunters, Dr. Maura Reinblatt and her fiancé, have been looking for a place in York.
Reinblatt is a plastic surgeon from Baltimore and wants to be near her new job at Wellspan.
One place they looked at recently was a condo apartment complex near Sovereign Bank.
At South George Street and College Avenue construction is underway at a new townhouse rental community.
York city officials said the apartment market is strong. Fallout from the foreclosure crisis may be one reason. Another reason may be the decision by a growing number of people to live in the city and not in the suburbs.
"We actually have conducted a market study recently that says there is a healthy market for the city for higher-end and loft-style apartment living," said York Economic Development Director Kevin Schreiber.
Casey Brenner of York Property Management said the surge in apartment rentals is real. The business owner said he has seen a 30-percent increase in apartment rentals over the past two years.
"I think people are scared to buy right now. They don't know where the bottom is at. I think it is very safe to rent -- no taxes, no maintenance issues," Brenner said.
A former old cigar factory is the newest apartment building in the York area to be turned into apartments with a dozen luxury units. It hasn't opened yet, but three apartments are already rented out.
Builder Jason Ilyes said he is confident about finding other tenants.
"We'll open in two months and we'll have them all rented out," Ilyes said.
According to York Property Management, rent at higher-end apartments runs between $850 to $1,250 a month.


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From the air, Queen's Day in Amsterdam must look like one giant, pulsating orange blob. It certainly felt that way from the ground.
Since the late Queen Juliana took office in 1948, the Netherlands has celebrated Koninginnedag on April 30. Now her daughter, Beatrix, sits in the throne in the House of Orange, but the day remains the same because B's birthday is Jan. 31, and who wants to play outside then?
Different towns celebrate with different levels of intensity, and not surprisingly, Amsterdam's fest is the most intense. But all Queen's Day events feature "vrijmarkten," or free markets, where folks set up little yard sales/street sales/flea markets all over town, featuring the usual yard sale treasures and trash.
In Amsterdam, where we were, the crowds started to pour into town around noontime, with many folks dressed in orange clothing, wigs, boas, hats, nail polish and even fake eyelashes. Wessel wore a lovely blow-up orange crown the entire day. I was decked out in orange sweat pants and an orange top. I felt foolish early in the day, and proud later, after fielding many compliments (at least that's how I chose to interpret the attention).
By far the majority of partiers were in their teens and twenties, but there was a smattering of old folks like us. Beer and vodka were the drinks of choice, and the youngsters started early. We stopped at the Museumplein for a look at the pop/rock concert, then literally had to dance our way through a street party before we reached Vondelpark, a long, narrow park that on Queen's Day becomes a haven for families.
Vondelpark was our favorite stop, as it was plenty festive but not rowdy. Little kids and families set up their little yard sales, and also made games and sold homemade trinkets. (This was also the only place with ample portable potties, FYI.) A lot of kids were drumming for dollars, and one man set up a drumming station, charging $5 for five minutes of drumming. One man staffed a "compliment station" – 50 cents for a little compliment, 75 cents for a big one, and $1.50 for an "ego boost."
Our favorite silly game was "Challenge the Ash Cloud," created by three friends in Amsterdam. A painted half-collapsed umbrella signified the Iceland volcano. It "erupted" whenever one of them worked a bike pump that blew air from the bottom, pushing out a mountain of flour. The contestant had to fly a paper airplane over the volcano's mouth and land it safely on the runway. Three throws cost about $1, but if you could spell Eyjafjallajökull (which we witnessed someone do), you got to play for free. It was hilarious.
At around 5, we started to follow some of the more popular canals, which were packed with boats of all shapes and sizes. Several were set up like party barges, complete with DJs with turntables and giant speakers. Then we came upon the craziest sight of all – for about the length of one city block, from one bridge to another, the canal was so jammed that the boats could barely move forward. It was like standing outside of a dozen open-air discos. One boat even had a smoke machine on it. It was joyous and crazy and loud.
By about 8, we realized we'd never make it to the very center of town without suffocating in a sea of people, most of them by then filled with alcohol, so we headed away from the merriment, basking in the glow of the orange.


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Better-Than-Chicken Turkey Salad
This Waldorf-inspired turkey salad combines cubes of tender roasted turkey with toasty almonds, juicy red grapes and crunchy celery. The salad is dressed with a glorious honey-mustard dressing seasoned with plenty of zesty lemon. A scoop of this salad served atop crisp lettuce will delight "ladies who lunch!"
Tips and Techniques
* To Toast Nuts: To intensify the flavor of nuts, toast them before adding to your dish. To toast in the oven, spread the nuts in a single layer on a baking sheet. Place in a 350 degrees F oven and toast, shaking the pan occasionally, until they are light golden brown. To toast on the stovetop, place the nuts in a dry sauté pan large enough to accommodate them in a single layer. Place over medium heat and cook, stirring frequently, until they begin to color. Remove from the heat, then immediately remove from the hot pan to stop the browning process.
Serves 6
Exclusive recipes provided by Viking Cooking School.


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The Sandstone Cotton Oxford Bell Tent With Zipped in Ground Sheet
These tents offer incredibly easy access, with a door height of 2m.
Exclusive to Boutique Camping, this tent gives you all the features of our Cotton Bell tents in a more affordable new style.
It's thanks to our unique Oxford canvas fabric. We spent the past 2 years searching and perfecting our oxford canvas material - one that would have the same look and feel as cotton but that would perform better, so we engineered our exclusive Oxford canvas, which is waterproof, holds colour better and is stronger and more durable. It's less prone to mould or rot (goodbye mildew spots!) and we've added PU coating and extra waterproofing via taped seams. Our unique Oxford canvas comes in Sandstone or a cool grey colour and is perfect for your all your glamping trips.
All the great features you'll know and love from our Bell Tents are here, like the heavy-duty, zipped-in groundsheet, which you can easily unzip to roll the sides up air the tent in the day. At the top, you'll find zipped windows and vents and as the material is less breathable than cotton, we've added extra ventilation.
In front, a zipped secondary mosquito net door will keep out critters, while a 32mm central pole keeps the tent held up from within, structured with thicker-than-average metal guy ropes stretching down and extra-strong pegs that won't bend.
This 5m size offers enough room for up to six adults to sleep on blow-up beds inside, but we think it's a great option even if there's just two of you, creating the feel of a lavish open-plan home from home. And it can be assembled by just one person!
The Oxford offers up the look and feel of our much-loved Bell tents without the price tag or compromising on any of the quality. It even comes with a 12month guarantee so you can buy with confidence.
Easy to set up, taking one person around 10 minutes, even the most novice campers!
Check out the Camping With Style review for the Oxford bell tent by clicking here.


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Water SA
versión On-line ISSN 1816-7950
versión impresa ISSN 0378-4738
Water SA vol.36 no.5 Pretoria oct. 2010
The defouling of membranes using polymer beads containing magnetic micro particles
David McLachlan*
UNESCO Associated Centre for Macromolecules and Materials, Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
Polymer membranes provide a good method of obtaining potable water but, as membranes always foul during water purification, the flux drops with time. Methods of physical cleaning of the polymer membranes, which do not require the plant to be shut down for lengthy periods, are very attractive and also do not generate any waste fluids. This paper reports on an investigation into the possibility of obtaining flux enhancement during the filtration process, as well as the cleaning of membranes, using magnetic polymer beads moving under the influence of an AC magnetic field. Methods, procedures and results for cleaning membranes using magnetic beads, at zero trans-membrane pressure, are described.
Keywords: membrane cleaning, magnetic particles
Membrane filtration of aqueous effluents is a technique widely used in water purification in the food industry, to clean industrial effluents prior to discharge or reuse and to obtain potable water from various sources (Porter, 1990). The fouling of membrane filters during the filtration process of all aqueous effluents is a well known phenomenon. Fouling of the membranes causes a decrease in permeate flux and eventually the filtration process becomes so inefficient that a cleaning procedure must be initiated.
The fouling of the membranes is characterised by a rapid initial decrease of flux followed by a medium or slow decrease in the permeate flux (Song, 2000; Czekaj et al., 2001). It is mainly the sub-micron proteins and polyphenols, i.e. particles smaller than the membrane pores, which are considered to be the cause of the initial rapid membrane fouling (Czekaj et al., 2001). After this the flux decreases due to the formation of a caking layer. When necessary, in order to restore permeate flux, the filtration process has to be interrupted to clean or replace the membrane filters. For economic reasons, a membrane cleaning procedure which does not seriously interrupt the process, or use chemicals which are hard to dispose of, is preferable. Cleaning by the use of scouring polymer-coated magnetic beads, which can be rotated and manipulated by magnetic fields, offers both of the above advantages.
There is no previous work of this nature to review. However an internet literature search found numerous references to magnetic beads used in drug delivery, magnetic beads carrying water purification chemicals and, more controversially, to the ability of magnetic fields (AC and DC) to prevent fouling in reverse osmosis (RO) systems. Therefore, this review will be limited to a brief mention of the other physical methods for cleaning membranes..
A number of 'physical' membrane cleaning techniques have already been investigated, which include back flushing, cross flushing, and back pulsing (or back shocking) (Redkar and Davis, 1995; Wetten, 1995; Parnam and Davis, 1996; Kuberkar et al., 1998; Redkar et al., 1996; Tanaka et al., 1995; Kuruzonovich and Piergiovanni, 1996). Although these techniques, applied in a non-continuous way, could be successfully used to clean membranes and partially or completely restore the original flux, they seem to be inefficient in the removal of some adhesive foulants (Czekaj et al., 2000). Czekaj et al.(2000; 2001) found rapid continuous back pulsing from the permeate space into the feed space to be very effective in maintaining an enhanced equilibrium flux. For instance, Czekaj et al. (2000; 2001) used infrasonic back pulsing at frequencies of 5-10 Hz and achieved, with standard cross-flow filtration, continuous permeate fluxes which were 3 to 4 times greater than those for fully fouled membranes.
This paper concentrates on the cleaning of membranes at zero TMPA. A more detailed account of this work, and a description of the largely unsuccessful attempts to obtain flux enhancement by continually passing the beads over the membrane, are given in McLachlan et al. (2009).
The experimental systems
Magnetic materials used in the beads
It is known that strong permanent magnetic particles would give stronger torques in a uniform field and larger forces in an inhomogeneous field than soft magnetic particles. Therefore magnetically hard hematite was used to make permanentmagnet polymer beads. No established method for producing nano-hematite was found in the literature but, if small enough, hematite particles will become super-paramagnetic. However, experiments using hematite powder (approx. 10 μm in diameter) showed that it retained a more than adequate permanent moment. Therefore, the beads and particles produced and tested in this report all contain hematite powder (which is mined in South Africa). Other possible fine permanent magnetic particles were investigated but found to be not suitable or too expensive for practical use (McLachlan, 2009).
Preparation of magnetic beads and particles
Commercial hematite powder was successfully compounded, with and without surface coatings, into polyethylene, by Dr. Breeksting from Tshwane University of Technology. The volume percentages of hematite powder needed to give beads which rotated in a magnetic field, but did not clump together in a magnetic field, was determined experimentally using 3 mm epoxy beads into which hematite had been embedded, and these became the target volume fractions. The volume percentage for the 2 extruded hematite/polyethylene materials was 8.15 and 8.16%. As the compounded materials were almost spongy, due to having been quenched into water, sheets of the materials (about 0.1 mm thick) were prepared in a hot press. These sheets were cut into small sections, which were then reduced in size by cryogenic milling and separated into 38-75, 75-150 and 150-218 μm batches of granular particles. It was then attempted, without success, to make these irregularly shaped particles more spherical. As this was not successful, and it was felt that the sharp edges may damage the membranes, only a limited number of experiments were done using these magnetic particles.
The most successful method of bead preparation was to encapsulate the SA hematite into poly acryl nitrile (PAN) beads. All experimental results reported here were obtained using PAN beads, for which a spraying procedure was developed to create magnetic microspheres from a dissolved polymer solution. The actual method used was to spray a PAN-dimethyl formamide solution, in which the correct amount of hematite was suspended, into a bath of a non-solvent liquid phase. This solution was placed in a glass tube with a fine (± 2 mm) point, with a ±1 mm orifice at the bottom. This tube was surrounded by another annular glass tube, which also had a reduced diameter at the bottom, to match the tip of theinterior tube. Nitrogen flowed in the annular space between the 2 tubes. A fine spray was created by the fast-flowing stream of nitrogen over the point where the solution exited the inner tube. (The shape of the tip, combined with the fast flowing stream of nitrogen over it, produced an aerosol effect.) The small droplets that formed were allowed enough 'falling' time from the tip, before they fell into the bath containing a non-solvent phase, for the surface tension to cause the formation of spherical droplets. The time needed for this sphere formation necessitated the tip of the spraying device to be 1 m above the surface of the non-solvent phase, which was usually a 75% acetone:25% water mixture.
Beads, with diameters ranging from 15 μm up to 600 μm, were produced. Wet sieving was used to separate out the various fractions. Most of the beads were between 100 |m and 300 |m in size. In the initial experiments the size range used was 50 to 100 μms, as very fine beads could more easily be passed through membrane elements. Unfortunately only a small fraction of the product lay in this range. In later experiments the size range used was 100 to 180 μm, as the proof of concept using flat test cells was more important at this stage than the necessity for the beads to pass through the spiral wrap membrane element feed space cloth.
Scanning electron micrographs (SEM) (Fig. 1) showed the beads to be almost perfectly round. Cross-sections of the beads (Fig. 2) showed the beads to be inhomogeneous and to contain a large fraction of water. Figure 3 shows a collection of beads produced by this process.
After preparation, the beads had to be poled in a high magnetic field, in order to induce a permanent magnetic moment. A M-H loop of some of the beads was made, using a vibrating sample magnetometer (by Professor Doyle of the University of KwaZulu-Natal); this showed that the field (4 000 G) available from our permanent magnet was insufficient to fully magnetise the hematite. Therefore the beads and particles were poled in an electromagnet, giving in excess of 8 000 G, at the Physics Department of the University of Cape Town. The remnant magnetisation in the hematite after this was 2.5 x 105A·m-1. Poled hematite loaded beads could be easily activated by the magnetic fields described in the next section.
The magnetic field configurations
Initially the AC magnetic fields were provided by a pair of Helmholz coils, which gave 57 G·A-1. The maximum continuous current was found to be 3 A (170 G), but 5 A (285 G) could be used for short periods. (In preliminary tests on a flat sheet in air and in water, all the magnetic spheres and particles started to move in a root mean squared (RMS) AC field of less than 57 G.)
In order to increase the AC magnetic field and to create a downward inhomogeneous field (to create a force on the particles) 'transformer' cores were used.
The E core field magnet: A transformer coil consists of an E and an I section which, when placed together (EI), provide a closed magnetic circuit. A single winding was wound around the central section of the E piece, which had a cross section of 55 mm x 45 mm, and the centre of the membrane was placed directly 11 mm above this section. For a current of 1 A, the field at the centre of the membrane was found to be close to 80 G and to drop to 60 G at the corners. The vertical gradient at the centre was found to be 0.75 G·mm-1 or 0.75 T·m-1. Most of the experiments done in this project used this E field magnetic configuration.
The rotating magnet: The calculations given below show that there is a possibility that the beads were flipping (i. e. changing direction or spinning in a very small fraction of the period of the AC field after the field was reversed) and therefore not able to effectively clean the membrane, using the E field magnet described above. In order to overcome this, a rotating field system was constructed. This consisted of 2 pairs of strong permanent magnets mounted at the tips of an aluminium 'U' shaped frame. The field at the centre was found to be just over 500 G. The 'U' was rotated by a variable speed stirrer motor and the revolutions per minute were measured, using an adapted bicycle speedometer. The highest rotational speed used was 126 r-min-1, as above this value the apparatus became unstable. The inputs and outputs of the cell (described below) were adapted so that all the tubes entered and exited through the upper section of the flat cell and the open section of the 'U'. This enabled the cell to be placed horizontally on the axis of the 'U' and for the beads to be rotated about the central axis of the U, being locked onto the rotating B field, so that there was no spinning. The field provided by this system was in effect an AC one. Note that the 500 G field is fairly uniform so no downward force was exerted on the beads. In all the other field configurations used the magnetic field was always perpendicular to the membrane.
Calculations of the torques and forces exerted on the beads
As it was not possible to measure quantities such as the torque exerted on the beads and the resulting angular acceleration, as well as the magnitude of the downward force, these are calculated below. The calculations will be made for a 200 |m spherical bead, which is a bit larger than the ideal size, but the radius of 100 |m, can easily be scaled. All calculations are in SI units.
Density of bead (20 mass % hematite) 2000 kg·m-3.
Volume (V) of bead (5 volume % hematite) 4 x 10-12 m3
Mass of bead 8 x 10-9 kg
Saturation magnetization of hematite 5 x 105A·m-1.
Remnant magnetization of hematite 2.5 x 105A·m-1.
Remnant magnetization (MR) of above bead = 12.5 x 103A·m-1
Magnetic moment (MRV) = 5 x 10-8A·m2
Force on a dipole particle in a magnetic field: F = μ( MrV) δB/δL N
For an inhomogeneous field of 1 G·mm-1 (δB/δL)(or 10-1 T·m-1): F 5 x 10-9 N
Acceleration (F/M) 40 N or 4 x gravitational acceleration ( 10 m·s-2)
(a 3g acceleration (force) was measured on several grams of beads, in the DC inhomogeneous field of the E core magnet, using an electronic balance)
Torque on bead τ = MRVB 5 x 10-10 Nm for B = 0.01 T (100 G).
Moment of inertia of bead I = 2Mr2/5 3.2 x 10-16 kg·m2
Angular acceleration of bead τ/I 1.6 x 106 rad·s-2
After 0.01 s angular velocity ω 1.6 x 104 rad·s-1
Speed on surface = ωr 1.6 m·s-1
These calculations show that that the magnetic fields exert a more than adequate torque to rotate the magnetic particles on the membrane. The above calculations also indicate that, with most of the fields used in this report, the beads were probably spun through 180º very shortly after the applied field changed sign (i.e. in a fraction of a quarter cycle), and remained aligned with the new direction of the magnetic field for the rest of the half cycle, after which the bead again spun through 180º. The calculations also show that the inhomogeneous fields used in these experiments provided a significant downward force on the particles. In most instances this force was greater than that provided by gravity.
The flat cells used in the project
A rectangular, flat-bed micro filtration module of 100 mm length, 32 mm width and 38 mm ( two 19 mm plates) height, was used in all the flat-cell experiments. The modules were made of polymethyl methylacrylate (perspex) for the low pressure experiments and polycarbonate for the RO studies. Each consisted of 2 plates (each 19 mm thick, 200 mm long and 94 mm wide). The feed space cavity in the top plate (2 mm deep, 88 mm long and 30 mm wide) had three 2 mm inlet pipes at each end which, through separate manifolds, were connected to the input and output feed lines. The membrane rested on a sintered brass plate, set in the lower perspex plate, and below this was another cavity, 13 mm deep, 88 mm long and 30 mm wide, to collect the permeate. The effective membrane area was 0.0032 m2 (100 mm x 32 mm), which was the area of the brass sintered plate. The membrane was placed on the sintered plate and the 2 halves were clamped together by a system of 12 nuts and bolts and sealed with an O-ring.
The low pressure flat cell filtration plant
A schematic diagram of the plant used is given in Fig. 4. Either the clean RO water or the fouling solution (for the alumina powders, the reservoir was placed on a magnetic stirrer) was used to feed to the pump by the appropriate choice of valves (V1 or V2). The flow rate and applied pressure were controlled by the bypass (V3) and exit valve (V4) from the pump, in conjunction with the cell exit valve (V9). The feed entered the cell through V5. The TMP in the cell, which was largely determined by V9, was read on a pressure meter. The permeate flowed into a beaker on an electronic balance and the mass was measured and recorded, as a function of time, by a computer connected to the balance. Valves 5 to 8 were used to introduce beads for cleaning at zero TMP, as will be described below. Valve 7 was used to introduce the beads when it was attempted to use a continuous flow of beads over the membranes to obtain cleaning at non-zero TMPs (McLachlan et al., 2009) and V6 was a seldom-used bypass valve.
The RO flat cell filtration plant
An existing RO plant was modified to carry out this project. The layout of this plant was very similar to the layout given in Fig. 4, but the piping was all made from stainless steel, rated at over 5 000 kPa. The pump used could give a maximum pressure of 5 000 kPa and also had an excessively high flow rate. Therefore, the pressure and flow rate were controlled using Valves 3 and 9 (see Fig. 4). To readily access the cell inside the available magnetic fields, it was decided to link the high pressure stainless steel part of the plant to the cell using 1 000 kPa flexible pipes and very convenient snap-in connections. Therefore this system limited the testing to low pressure membranes, designed for brackish water. In this plant the pressure was measured at the input of the cell and the flow rate after the throttling valve (V9). When running the plant, it was found that the feed pressure tended to oscillate. Therefore, to dampen this oscillation, an 800 kPa ballast tank was installed. The presence of the ballast tank meant that it took up to 20 min to adjust the feed flow and pressure to the desired values. The beads used to clean at zero TMP were introduced into the polycarbonate cell through V8. Unfortunately, due to the high pressures, a simple continuous flow system was not practical and the one-shot system meant that there was limited time to see the effect of the beads on the fouling of the RO membrane.
The membranes and foulants used in the cleaning of foulant layers
PALL Biodyne 0.20 μm pore size nylon membranes (Pall Corporation)
PALL Biodyne 0.45 μm pore size nylon membranes (Pall Corporation)
Polysulphone membranes (PSM) made in the laboratory
The surface pore size of the polysulphone membrane was examined with a SEM microscope and the pore sizes were found to be much less than a micron. Also, as its clean water flux lay between that of the above 2 nylon membranes, the polysulphone membrane is obviously also a micro membrane.
Dextrin (0.5 g·l-1). (Sigma Aldrich CAS# 9004-53-9) Note that the concentration of 0.5 g·l-1 used for the dextrin solution was the same as that used in concurrent experiments on cleaning a spiral wrap polysulphone element using backpulsing. The dextrin, which was produced from cornstarch, had a wide range of molecular weights.
Alumina powder (1 g·l-1) with a mean diameter of 1.0 μm and a small size spread
The membranes and foulants used in the cleaning of RO membranes
The membranes used in this work were cut from a small commercial low pressure brack water RO element. This was a FILMTEC RO Element XLE-2521, designed to operate at 690 kPa, with a maximum salt concentration of 500 mg·kg-1.
As the feasibility of this cleaning method had to be established fairly quickly, initial trials were done using a rapid fouling solution (RFS), as used by Lisitsin et al. (2005). When using this foulant solution, the pH and temperature were important and so had to be kept within the bounds for rapid fouling specified by Lisitsin et al. (2005). The standard RFS was made up using 22 g CaCl2, 1 g MnSO4 and 14 g NaHCO3 in 100 of RO water.
Procedures for low pressure fouling layer and RO filtration cleaning experiments
The procedures used at finite TMP
As the experimental results were very unsatisfactory and no significant improvement was observed, please refer to McLachlan et al (2009) for a description of the modifications to the plant and the procedures used to obtain a continual flow of beads, at finite TMPs.
The procedure used for the cleaning of fouling layers at zero TMP
This procedure or routine was used in all the experiments on cleaning and was performed at zero TMP. The experiments themselves are reported on in the 'Results' section.
To introduce the beads for zero TMP experiments, a large syringe was used to inject a suspension of beads into the cell cavity, through an aperture (V8 in Fig. 4) in the top plate, directly into the feed space. The water (and beads) contained in the large syringe flushed the feed space during the introduction of the beads. The beads were kept from moving off the membrane by a sieve that was inserted to cover the exit pipes. As the feed side valves (V5, V6 & V7 in Fig. 4) were closed during this procedure, virtually no beads moved towards the feed pipes. After this the beads could be spread using a small permanent magnet until a fairly uniform layer of dispersed beads fully covered the active area of the membrane and also filled the feed space. At this stage, the feed space (2 mm deep, 88 mm long and 30 mm wide) was estimated to contain about 2.5 m of beads (comprising 50%, by volume, of the feed space). With a density this high, the motion of the beads in the confined space, and the continuous collision of the beads with each other and the walls of the cell, meant that some of the spinning beads were always in contact with the fouled membrane. After cleaning, the beads were flushed off the membrane, using a RO-containing syringe, via the entry port, which was not covered by a sieve. The 'best' procedure/sequence, described below, was the result of many trials and variations, which are therefore not reported on in this paper.
The plant filtration system was operated as follows (a typical flux-time plot, Fig. 5, illustrates this procedure). First the membrane was mounted in the cell and the cell connected to the system. The clean water value was then measured for 5 min using RO water at 50 kPa (A in Fig. 5). The retentate flow rate was found to be about 70 m·min-1 (i.e. at the bottom end of the membrane) and about 70 m·min-1, plus the permeate flow, at the top (input end) of the membrane. The cross-flow velocity at the exit end of the membrane was about 0.0233 m·s-1. The feed to the pump was then changed to the fouling solution/suspension and the membrane was fouled (B) until the permeate flow rate was less that 10% of the clean water value, or for 5 mi, whichever occurred first. Reverse-osmosis water was then passed over the membrane for 5 to 10 min to remove any loose foulant from the system (C). After this period the pump was switched off and the valve in the feed line was closed. The beads were introduced (D) into the cell, at zero feed pressure, using a syringe, through the entry port into the feed space of the cell. The excess water flowed out through the retentate ports, which were covered by a fine sieve. After the surface of the membrane had been covered with beads the entry port was closed and the bead density on the surface of the membrane was made more uniform using a small permanent magnet. The E field electromagnet (or in some cases the rotating magnet) was then re-activated (E) for 5 min. This was the period during which the cleaning took place. After 5 min the electromagnet (or rotating magnet) was deactivated and the beads were withdrawn from the system using the syringe. This also resulted in all or most of the foulant that had been cleaned off by the beads being removed from the feed cavity. Reverse-osmosis water at 50 kPa was then reintroduced (F) for 5 min to measure the new RO flow rate. After this period beads were again introduced (G), using the same procedure as before, and the magnetic field reactivated for 5 min to further clean the membrane. After this 5 min period, the field was again turned off (H) and the beads and any foulant in suspension were removed. Finally, the flow was again measured using RO water (I) for 5 more minutes.
It must be emphasized that it was no trivial exercise to introduce the beads onto the membrane, so that they covered the membrane completely and contained no air pockets. Repeatability is further hindered by the distribution of the beads which changed as a result of the AC magnetic fields. This gave rise to what was initially a reasonably uniformlycovered membrane, having more- and less-densely covered regions during the cleaning cycle.
A computer was connected to an electronic scale, upon which a beaker was placed to collect the permeate, and logged the mass registered on the scale every 30, 60 or 120 s. The permeate flow and then the flux were calculated from these results and plotted as a function of time to create the figures given in this report.
The procedure used for the RO cleaning experiments at zero TMP
As these tests involved introducing the beads onto the active area of the membrane, after it had been fouled, a port (V8 in Fig. 4) was placed in the top plate of the cell, over the input side of the active membrane area (sintered bronze support area). For these tests, sufficient beads were then introduced through this port, using a modified syringe, to cover the active area of the membrane. In order to confine the beads to this area, a vertical sieve (made of fine-mesh stainless steel and anchored to the polycarbonate top of the feed space) was placed at the exit of the flat cell.
The procedure was to first measure the clean water or RO flow rate. A RFS (Lisitsin et al., 2005) concentrate was then rapidly added to the feed tank which was continually being stirred. After this the fouling was monitored until no further drop in the permeate flow rate was observed. To add the beads after fouling the pump was stopped, and the water in the feed tank replaced with pure RO water. The system was then briefly flushed with RO water at a low pressure. With the pump off the beads were then added as described above, after which the magnetic field was switched on, with the desired amplitude and for the selected period. Note that the cleaning of the membrane was done at zero TMP. The beads were then withdrawn using the same syringe through port V8. This port was then closed, the pump started and a new RO flow rate measured.
Results and discussion
Cleaning of the membranes at finite TMP
Considerable effort (McLachlan et al., 2009) was put into modifying the systems so that a continual flow of beads could pass over the membrane, together with the fouling solution, resulting in a continual flux enhancement. At best during continual flow the beads coved 5% of the membrane surface. At relatively low TMPs the beads were observed to remove the surface layer, but not to improve the flux. Subsequent SEM examination showed the foulant to still be present close to and in the pores of the membranes. Therefore it had to be concluded that the flow into the pores was providing a binding force for the foulant. At higher TMPs it was found that some of the beads became embedded in the surface layer.
Cleaning of the membranes at zero TMP
The foulant/membrane combinations for all the experiments performed are listed in Table 1 and some of the results are given in Figs. 5 to 8. Table 1 presents a summary of the results obtained in this paper. The units of all fluxs are m3m-2h-1. The last column is obtained by dividing Column 9 by Column 6 and multiplying by 100. The experimental results reported are for those using the E field magnet (1a to 5b in Table 1) and the rotating magnet (7a to 7e). Note that during the cleaning period the foulant was mixed back into the water in the feed space, but most of this was washed out, using a syringe, before the TMP was reapplied. The results given are for the E magnet, where the field at the centre of the membrane was 80 G, experiments were all repeated 3 times (see Table 1). (Note that the E magnet was used when attempting to clean membranes with flowing beads and a positive TMP.) A few results using the rotating magnetic field are also given in Table 1.
Figures 6 and 7 show fouling curves for alumina, which was a fine, chemically inert, particulate foulant, using both the nylon membranes and the polysulphone membranes (PSM) discussed above. The decline in the permeate flow rate during initial clean-water periods for the nylon membranes was attributed to conditioning of the membrane. Figure 8 shows fouling curves for dextrin, which is a far more 'sticky' foulant than alumina, using the PSM, which has smaller pores and is more suitable for dextrin. Table 1 summarises the results. From Table 1 it can be seen that the results were not very reproducible, especially when using the 2 nylon filters.
A control experiment (see Fig. 9) was carried out to see if flushing RO water in and out of the cell had a cleaning effect. In this experiment the membrane was first fouled, after which RO water was added to the cell above the membrane, where it was left for 5 min at zero TMP. The water was then removed, as in the previous experiments. After this, RO water, at 100 kPa, was passed over the membrane and the flow rate re-measured. The results for this experiment are shown in Fig. 9, where it can be seen that no improvement in the RO flux was observed, so introducing and removing the RO water had no cleaning effect. It should also be noted that, unlike observations in the previous cases presented in this section, no foulant was seen in the water flushed from the system, indicating that the fouling layer was still intact.
An example of the results obtained when cleaning the membrane, using the rotating magnetic system, is given in Fig. 10. The results for all these experiments are given at the bottom of Table 1. The flux values for the nylon membranes showed a preliminary spike after cleaning. It would appear that the cleaning obtained using the rotating field was better than for the fields obtained using the E field magnet, but as a rotating field (as used in these experiments) is very difficult to implement around a membrane element, a large amount of experimental data was not acquired.
All the results showed an increase in the flux or flow rate after an initial bead cleaning treatment and sometimes an additional improvement in the permeate flux or flow rate after a secondary treatment. From the experiments reported here, it can be seen that the permeate flow rate can be significantly improved by the cleaning action of the PAN beads, at zero pressure, either in the alternating field of the E magnet or the rotating field. However, an examination of Table 1 shows that the rotating field is probably more efficient.
Cleaning RO membranes at zero TMP
Bearing in mind the fact that magnetic beads had been found to effectively clean the fouling layer only when the TMP was close to zero, it was decided as a first step to see if the beads could remove a scaling layer at zero TMP, so as to give an improved permeate flow. This necessitated the introduction of a large number of beads onto a scaled membrane and setting them in motion for the required time, at a frequency of 10 Hz using the E field magnet. The cleaning of the membranes and all subsequent measurements were done using RO water. Only results for membranes cleaned at zero TMP, using this procedure, are given in this report. In all these experiments the membranes are cleaned twice after which 500 mg·kg-1 salt water solution was reintroduced and the permeate flux logged for a further period.
Figure 11 gives a plot of the permeate flux versus time and shows the initial conditioning of the membrane for 3 h and then the change in flux when a 2 x RFS fouling solution was introduced for 1 h. After this the figure records where the first cleaning (zero flux) was made between 454 and 5 h. The subsequent measurement of the RO flux was done between 5 and 6% h. Figure 11 then shows a repetition of the cleaning procedure for 15 min and the subsequent RO flux measurement from 64 to 7 h . Finally the figure records the effect of introducing a 500 mg·kg-1salt solution at 7 h. The RMS field for all these experiments was 80 G from the E field magnet. From this figure one observes that the cleaning procedure actually decreased the flux.
Figure 12 shows the initial conditioning of the membrane for 1 h and then the change in flux when a 3 x RFS fouling solution was introduced between 1 and 3 h, After this the figure records where the first cleaning (zero flux) was made for 30 min and the subsequent measurement of the RO flux. The figure then shows a repetition of the 30 min cleaning procedure after 4 h and subsequent RO flux measurement. Finally the figure records the effect of introducing a 500 mg·kg-1salt solution after 5 h. Note that the drop in the flux upon adding the 3 x RFS foulant was considerably larger than in the case where 2 x RFS concentration was used. This figure shows that the cleaning procedure improved the flux slightly after the first clean but that it returned to the first fouled value (3 h value) after the second clean.
The above results were obtained using a AC field of 80 G. The results (not shown) obtained when using a 3 x RFS concentration and RMS fields of 48 and 24 G in the E field magnet were very similar to those shown in Fig. 14. This indicates that the slight improvement of the flux after the first fouling is nearly constant between 24 and 80 G.
In order to try to understand what is happening, the images obtained from a series of SEM micrographs are presented and discussed.
Figures 13a-e all show images at a magnification of 50 x. Figure 13a is an image of a conditioned membrane, Fig. 13b is after 2 x RFS fouling and Fig. 13c is after cleaning the fouled membrane. Note that these images are all very similar and it has to be assumed that 2 x RFS fouling is mainly in the nanopores. Figure 13d shows that a cloud-like pattern of light on dark areas was obtained after 3 x RFS fouling and Fig. 13e shows the light cloud-like areas to have gone after cleaning. It would appear that the 'clouds' indicated a thicker flakier fouling layer, which could be partially cleaned by the beads.
Figure 14a is an image of a conditioned membrane and Figs. 14b and 14c were taken from a 2 x RFS fouled and cleaned membrane, respectively.
There may just be a discernable difference between these 3 images but it must be concluded that 2 x RFS fouling did not produce a fouling/ scaling layer which could clearly be seen using even high magnification for the SEM micrographs.
Figure 14d shows an enlargement of a light cloudlike area in Fig. 13d, which clearly shows a heavy scaling layer. Figure 14e is an enlargement made from a dark area in Fig. 13d and shows that less fouling had occurred here than was observed in Figs. 13d and 14e.
Figures 14f and 14g show images as seen at 500 x magnification, after a 3 x RFS fouling and bead cleaning. Figures 14f and 14g are from the more heavily- and more lightly-scaled areas, respectively. The remnant scaling is seen to be somewhat heavier in Fig. 14f than in Fig. 14g and both are similar to what is observed for Figs. 14b and 14c. Note that no thick fouling layers, as seen in Fig. 14d, were observed on any of the cleaned membranes.
These images (Figs. 14d to 14g) allow the conclusion to be made that the beads are capable of cleaning off heavy, probably flake-like, scaling layers but do not remove the finer scaling layers/particles, which are more firmly bonded to the membrane and embedded in the membrane pores.
From the above, it must be concluded that the cleaning of fouled RO membranes with magnetic beads is not practical, as only the flux through heavily-fouled membranes can be somewhat improved.
This research has shown that beads, suitable for cleaning in conjunction with an AC magnetic field, can be made by blending hematite into polyethylene and poly acryl nitryl (PAN).
However, as the polyethylene beads are not spherical, all the reported work was done with PAN beads. As the experiments all showed that cleaning could only be done at zero TMP, it had to be concluded that beads could not continuously keep membranes from fouling and that the plant would have to be shut down in order to have the beads clean the membrane. From the flux-time curves it was concluded that the magnetic beads could only partially clean the membranes and that material in the pores and firmly bonded to the surface could not be removed.
The report also concludes that chemical-free cleaning of a filtration element at zero TMP, using beads, is possible but not practical in a spiral wrap membrane. One reason is that the feed space (which includes a spacer cloth) would have to be reasonably well filled with beads for the cleaning process to work and that after the cleaning the beads would have to be removed.
Unfortunately no enhanced flux is observed for a lightlyfouled RO membrane. Experiments also showed that an enhanced flux for a badly-fouled RO membrane cleaned by rotating beads was obtainable but that the resulting flux was similar to that obtained for a lightly-fouled membrane. This, plus the SEM images, allows one to conclude that while the beads are able to remove thick flaky layers, they are incapable of removing the initial scaling layers, part of which lies in the pores and is therefore inaccessible to the cleaning action of the beads.
In future experiments it may be worthwhile examining the use of magnetic beads in the partial cleaning of capillary membranes and elements. The beads are recoverable in a magnetic trap and the cleaning method does not use any chemicals. The beads would also be more closely confined on all sides by the membrane material and would therefore strike the membrane more often. Note that the size of the beads available determines the inner diameter of the capillaries that can be used as the beads must be able to be flushed in and out of the system without clogging. First experiments could use larger beads and capillaries to establish proof of concept. With the confined geometry in a capillary, it may even be possible to keep the membrane partially clean while passing the beads continually over it, with a low TMP.
Due to the porous nature of the PAL beads they could be impregnated with reagents or even drugs. The beads could then be manipulated magnetically to where they are needed. Experiments have been made to see if such chemically impregnated beads can be used to reduce fouling and as a boron-selective resin (Bryjak et al., 2009). (Note that Boron fouling causes problems in some RO plants).
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Received 21 January 2010; accepted in revised form 12 October 2010.
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