blackblog.

This year I will not be at home for christams – and sending a christmas gift half around the world in order to transport it back some month later is just stupid. So I got just some monetary gift for christmas in order to get myself something useful. Guess what I thought about: Getting some cheap electronic gadget – Mainly because this stuff is a little cheaper around here.

The last few weeks I looked around the city in order to decide what to get. I finally decided to get an iPod Nano with 8gb storage. The official price of Apple is here at 439s$ (~ 216 euro), which is already around 33 euro cheaper than the German offer. Checking out the prices at popular places like Funan Center or Sim Lim Square showed prices as low as 408s$. But lower than 400 seemed to be impossible… So just yesterday I checked at 8flags, which is the official computer store of Nanyang Technological University. And they got a really nice price…. 365 s$ (= 179 euro)! And there was just one left… So I directly got a shiny new iPod nano for christmas. To make it clear: I would not have purchased an iPod nano for 249 euro, because this is way overpriced – But 179 is ok to me.

Actually I really like it, but probably I will get some better headphones… They really suck. But the rest is just nice!

One thing really annoyed me – It was not possible to play all podcasts in a row (like in an playlist etc). But thanks to some people in blogosphere that already got a solution: Just turn off the “shuffle” option. Then you can play podcasts in a row. With “Albums” or “Songs” it is not working…

As stated in the last post, it started raining on Sunday. Actually it did not stop the whole night til Monday having a thunderstorm every 3-4 hours. And when it was not a thunderstorm, it was just raining. Sometimes faster, sometimes a little slower. It was just continously raining from Sunday morning til Tuesday night – Way heavier than the whole-rainy-day-rain you get in Europe (eh Great Britain).

As seen in the news, there had been 345mm rain in the 20hrs of Tuesday! This is even for Singapore a lot – leading to heavy flooding in the central and northern area of Singapore. The record rainfall per day was in December 1978, when they had 585mm on one single day. Just to have an comparison: In Nuremberg there are just 623mm per Year! In Singapore usually has just 284mm of rain in December – but this year definitively more compared to last year and way more than exspected.

Today it is better – Blue sky again this morning. But there is some heavy thunderstorm to be exspected around afternoon…

Another week at work is over and so it’s weekend again. This saturday I was pretty smashed, cause I got some kind of infection during the week… So after sleeping pretty long I decided to get it going quite slowly and just enjoy some books & coffee at Marina Bay.

Ah, then I remebered: The free Wireless-Network of Singapore was just launched this week – So lets test it! After checking out the Government Website informing about this project, I continued to sign up at SingTel, packed my Laptop and hit MRT. To get you some details about Wireless @ SG: It is a project giving free access to the Internet, sponsored by the Government. Anybody can sign up and use one of the (still increasing) number of hot-spots all over the city. The project will be on for 3 years – After that it will be decided what to do.

So I logged into the 54mbit g-wlan at Marina Bay using the Login I got from SingTel and the Password that was sent to my mobile phone via SMS. Everybody gets a bandwidth of about 512kbit – But actually, when there is more available, you get more. First try was successful – and after establishing the VPN link everything worked as needed. Yeah, that’s a nice service. You don’t need ultra-high bandwidth – I think it is a good idea to limit the bandwidth per user, cause then kids wont waste it with filesharing junk and block access for applications like SSH. Thank you Singapore!

Today I met Nina, the other intern at my company in order to get around Harbourfront. Actually, before that I got to SimLimSquare, the biggest mall for electronics in Singapore in order to get a RAM upgrade for my Laptop. After some searching I found a “Good, good last price, Sir!” – 167S$ for a 1GB PC2700 SO-DIMM of Kingston. Thats about 30€ cheaper than the German price. When you go to Sim Lim Square: Be sure to have the German price in mind! Don’t accept the first price they offer – and look around first! The shops at the 4th or 5th floor have better prices!

But lets get back to the topic – We met at 13:00 at Harbourfront. So first we walked up to Mount Faber, which is the highest “mountain” (haha 115m above sealevel!) in Singapore (as far as I know). From the top, you get a pretty nice scenic view of the central business district – and of Sentosa. … And again, there is a Merlion – The symbol of Singapor. We used the cablecar to get over to Sentosa – Yeah, it’s quite expensive (10S$), but the view is nice!

After hitting Sentosa we walked down to Siloso Beach in order to have some iced coffee… Siloso Beach is quite odd (as I mentioned in an older posting): A tropical beach with a nice view of the approaching container ships… But for an engineer this is really nice, it almost doubles pleasure *gg*. Our plan for today was getting to the Oceanarium. Because of the school holidays, there was a huge crowd waiting, but there was a special discount for students: 13S$ instead of 19S$! So we directly got in.

The first thing we saw, was the “Touchpool”. Guess what you can do there – Yeah right. Touch a whole bunch of fish. Actually it was my first time touching a ray or a puffy fish (for my CBI fellows: remember fugu fugu?). Nina and me never saw something like this before – This was actually a experience which made it worth visiting this place! A blue-stained ray has a very slippery surface – Never thought about that! I think something like this will never be seen in .de – Because all these animal-have-rights people would just get crazy.
At the lower level there was a tunnel under the main basin – Unfortunately it was so dark there that it was quite impossible to make nice pics. Especially because the fish moved pretty fast! It was very impressive looking at different kinds of sharks and wunderfully colored tropical fish – But watching all those fish made me hungry…

The admission for the oceanarium also included a free dolphin show at the lagoon, so we got on a shuttle bus to get there. it was really crowded but the show was worth it: Pink dolphins showing all kinds of tricks.

The last few days I was quite busy at work – so there were no postings. But after work I managed to get to some fruit market in order to have some tropical fruits that are not really available in Germany. So lets make a list of what I already got – I will start with the more “known” ones at get to the really unusual ones… And give brief explanation and rating (Maybe I get some more photos ready the other day):

• Young Sweet Coconut – With a very thin shell and thin layer of quite fatty flesh these mini coconuts taste amazingly sweet and intense. Unlike the Coconuts you can get in Europe, coconuts are here completely full of coconut water (actually the amount of water in a coconut is a measure for its freshness! Most surprising: There are reports, that you can use the coconut water as in intravenous fluid in case of blood-loss!)
• Belimbing (Starfruit) – In Germany all the Starfruits I had were green and quite sour. More like a lemon than some sweet fruit. But here you can get them completely ripe: Yellow, tasteful and really sweet!
• Pitaya (Dragonfruit) – This is one of the most amazing fruits I ever had: A dark red sheel and white flesh with little black seeds in it. The flesh tastes a little bit like Kiwi. Depending on ripeness it can be juicy and sweet or more balanced.
• Nangka (Jackfruit) – In the first moment you think of a taste like caramel and pineapple. Very unusual!
• Durian – In Singapore they call it “King of fruits” cause of its taste. Yeah, it tastes quite nice: A little bit like almonds with some caramel-vanilla-custard taste. The odor of this fruit is annoying. Probably you can compare this fruit to cheese: Smells bad, tastes good. But I think this is a must-have for Singapore visitors!
• Mangosteen – This unusual fruit with a hard shell covers a white juicy flesh with a taste of sweet-lemon with a touch of peach. Quite hard to get around here, but worth trying it!
• Red Jumbu (a kind of Persimmon) – When I first looked out at Wikipedia I did not find any information… By more distinct searching I finally found out that this fruit is related to the orange persimmon (Kaki or Sharon) that you can get in Germany. The taste although is quite different… Way more sweet and a little more bitter. Very refreshing when served cold!

And, do you know all these? I definitively did not, but at least I tried them all…. So, if you run across some of those fruits – Go ahead and get them! You will survive it!

But actually I got more targets on my list: Langsat and at least Lychee. But probably I will find some others too

Today I had my first day at Sulzer. It was pretty interesting and enjoyable – Very nice & smart colleagues. I will have a 44h week, which is quite reasonable. For my 3-month-internship I get 3 days off – Probably I will spent them to bridge Christmas and NewYear in order to get to HongKong or Shanghai.

My other challenge for today was: Get a prepaid card for my mobile phone… So I got to Orchard Road in order to drop into some mobile-carriers shop. After some checking I found a special offer of Mobile1 giving me 25S$ credit for worldwide phoning and 25S$ credit for local stuff by just paying 20S$  (about 10€) initial fee. First I thought of high rates, but by closer checking, this was not true… A SMS to Germany is just 6 euro-cents and a local SMS about 2 euro-cents. Talking is also quite cheap… To Germany about 30 euro-cents per minute and 10 euro-cents local. The only tradeoff at this deal is: There is a monthly deduction of about 5€ in order to keep free dial-in and connectivity running. Altogether this offer seemed pretty nice to me…

Yesterday the flight got into Changi about 40 minutes earlier than supposed – Thanks to nice tailwind! The Border & Customs stuff was pretty relaxed – I can’t understand why peoply freak out about the Singapore customs regulations… Everything seemed to be well-organised etc. Even at this point, it was easy to see, what the Singapore people like: The like to “Q”. Which means: Form a queueing line everywhere: At foodstands, bus-stops, taxi-stops, … After getting my luggage I decided to take a taxi to the NTU campus at the other end of the island instead of a 1,5h ride with public transportation.

The taxi ride was interesting: I had a pretty “chatty” taxi driver… After he found out, that I was from Germany he asked me a whole bunch of stuff regarding soccer – He definitively knew more than me about this topic! It took about 30 minutes from Changi in the eastern part of the Nanyang Technical University in the very western part of the Island… And only cost 25S$ (about 12 euros). We had some trouble finding my Hall of Residence at the campus, but after questioning some students we finally found it.

Recieving the keys for the room was also well-organised: The office knew that I would arrive outside office hours so they arranged that some senior student from the Hall got it for me. Then I met my room-mate for the next 4 months: A very nice 1st year student of Business Administration and Accountancy from Singapore named Harith. He also introduced my to the special features of the hall: They have a canteen which is open from 7-21h (and after first testing: pretty good & cheap), laundry service, kitchen and so on. Every room is equipped with a LAN port, which instantly worked (Proxy…).

After dinner we got to the pool in order to get a quick dip.
I finally got to bet pretty exhausted from the flight – but after falling asleep instantly I woke up the night at 3… Damn.

Man, after 4 years its done – No more exams left to get the university diploma in chemical engineering! Just the internship and diploma thesis is open
So lets summarize. I just finished my 8th semester with the last three (oral) exams namely in “Membrane Separation Technology“, “Thermal Seperation Processes II” and “Solvent Concepts for Catalytic Processes“. It turned out that finding books to dig into those subjects are pretty hard to find. So here is my suggestion what books & papers might be helpful to get a broad overview:

Membrane Seperation Processes (Prof. König):

• Rautenbach, R.; Melin, T.: Membranverfahren; Springer, Berlin, 2003
• Kraume, M.; Peters, T.: Entwicklungen und Pespektiven druckgetriebener Membranverfahren; CIT 77(2005), 5, S. 473-485
• Strathmann, H.: Die Elektrodialyse; CIT 56(1984), 3, S. 214-220
• Wijmans, J.G.; Baker, R.W.: The solution-diffusion model; Jour. Mem. Science, 107(1995), S. 1-121

Solvent Concepts for Catalytic Processes (Prof. Wasserscheid):

• Curzons, A.D.: Solvent Selection Guide; Clean Prod. and Proc., 1(1999), S. 82-90
• Endres, A.; Maas, G.: Die flourige Phase; CIUZ, 34(2000), 6, S. 382-393
• Schulz, H.: Short history and present Trends of Fischer-Tropsch Synthesis; Applied Cat. A, 186(1999), S. 3-12
• Reichardt, C.: Der Lösungsmitteleinfluß auf chemische Reaktionen; CIUZ, 15(1984), 5, S. 139-148
• Röper, M.: Homogene Katalyse in der chemischen Industrie; CIUZ, 40(2006), S. 126-135
• Wasserscheid, P.: Ionische Flüssigkeiten; CIUZ, 37(2003), 1, S. 52-63

Thermal Seperation Processes II (Prof. Arlt):

• Sattler, K.: Thermische Trennverfahren; Wiley-VCH, Weinheim, 2001
• Stichlmair, J.; Fair, J.: Distillation; Wiley-VCH, New York, 1998
• Mersmann, A.; Stichlmair, J.; Kind, M.: Thermische Verfahrenstechnik, Springer, Berlin, 2005
• Goedecke, R.: Fluidverfahrenstechnik; Wiley-VCH, Weinheim, 2006
• Deckert, P.; Arlt, W.: Simulierte Gegenstromchromatographie; CIT 66 (1994), 10, S. 1334-1340
• Birtigh, A.; Brunner, G: Abscheidung aus überkritischen Gasen; CIT 67 (1995), 7, S. 829-835
• Brunner, G.: Hochdruckverfahrenstechnik; CIT 75 (2003), 10, S. 1430-1433
• Schulte, M.; Kinkel, J.: Simulierte Gegenstromchromatographie; CIT 68 (1996), S. 670-683
• Stichlmair, J.: Zerlegung von Dreistoffgemischen durch Rektifikation; CIT 60 (1988), 19, S. 747-754 (Excellent!!!)
• Frey, T.; Stichlmair, J.: Thermodynamische Grundlagen der Reaktivdestillation; CIT 70 (1998), S. 1373-1381
• Storti, G.: Robust Design of Binary Countercurrent Seperation Processes; AiChE Journal 39 (1993), 3, S. 471-492

Most of these articles are reviews on this specific topic. They had been selected by just searching by Google Scholar. During my thesis (topic was: Measurement of partition coefficients of drug-like-solutes in micellar systems by ultrafiltration) this spring / summer it turned out to be way more useful than the (expensive) SciFinder. Especially the BiBTeX Export functionality really kicks ass (Just activate it by Scholar-Preferences)!

In the last days I finally converted my fileserver at home to the dm-crypt / LUKS infrastructure of the Linux-Kernel in order to replace the old crypto-loop infrastructure which was running for some time.
I also used this to cleanup my bitbucket and enlarge my md-raid5.

Actually I was quite impressed by the speed when I set-up a the md5 raid and added the LUKS container using blowfish-cbc-essiv:sha256 and started to copy my data to this… On my old Athlon 1000 I got about 15mb/s writing performance, which is quite impressing!

As you might probably know, I really developed a faible for coffee during the last few years, grinding the beans myself and celebrating the brewing-procedure… I prefer coffee beans of coffeemamas (Berlin). They provide excellent beans of different origins – But thats not the topic. Inspired by some magazines article, I spent some time to think of the process-engineers view of coffee. Maybe the knowledge I got at university, especially chemical thermodynamics and heat- and masstransport, is really good for some real-life topic. So here are my toughts:

• As clearly seen, the Latte Macchiato develops three seperate phases: Milk froth, coffee and milk. Obviously, this is caused by different density. But wait, milk should be on top of the coffee, cause it has more fat. But the reason that milk is the densest phase is simple: coffee is hotter and so gets a smaller density. Froth of course has the smallest density cause of all the air…
• Ever thought about this waving boundary layer between milk and coffee? Gravity is the reason why this waving is going to stop, cause engertically, a flat interface area is better than a waving one. The boundary layer itself is there, cause of the density difference.
• When a Latte Macchiato is served, the boundary layer is clearly to be seen, but when you wait some minutes, it gets to a color gradient and finally the whole glas is a brownish coffee-milk-mixture… My first thought was: Diffusion. Thermodynamically the entropy of the system wants to be maximal – so all the components want to mix equally. But actually diffusion is quite slow. As I said before, milk is cooler than the coffee – So the real reason seems to be convective mixing.
• It gets way more interesting, when you add some sugar to the milk-coffee system and use a spoon to mix it up: The turbulence causes the system to equally mix within parts of a second. But then, this nice interface area is destroyed… So mix the sugar into the coffee before adding it to the milk!
• Preparing the perfect milk froth depends on many parameters. My strategy is to heat up the milk to about 60°C and use a rotating milk-froth-maker (Milchschäumer). By surfing the net, I actually found a research paper on the “Macroscopic and microscopic structure of milk foam“, which gave me many new hints, to optimze my strategy So if you are interested in everything scientific in milk froth – read this PhD Thesis. It opens a whole new world!

There are way more aspects to look at (like the *ding* sound the spoon gives, when it hits the glass or all the extraction related things of coffee making…), but maybe I will look at those some other day