Reading app that I just can’t live without

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Today, the guys from Pocket send me my yearly statistics saying that I “skimmed” 3.5 million words or about 47 books (lets be honest, I didn’t really read all that text). I use Pocket for quite a while and over time it became the most important resource on my phone. Still, it is surprising how much time I spent with it! If you don’t use it, read further. You might want to give it a try…

Pocket is very simple, but very powerful reading app. I do believe that it is the best save-for-later service. It is flexible, available for all mobile and desktop platforms, and integrated with hundreds other applications (including Feedly). Pocket can store links to various types of content: text or videos, and its phone app will even read you saved articles aloud, using really good voice synthesizer.

After a while, I developed couple strategies for effective use of Pocket that help to improve and organize the collection. They are simple and might help you to enhance your Pocket experience as well.

Set your limit at 1000 articles

Always keep the library below 1000 articles (or any other arbitrary number you like). Once the collection reaches this limit, I take time and review saved stuff (randomly, but starting from the oldest items) searching for outdated or no longer interesting articles. If I find something boring, trivial, or no more relevant it gets deleted. Each time, about 20-30 articles go away, making space for the new ones.

This continuous distillation gradually improves the quality of the library. It will simply get better and more attuned with your interests. Nowadays, every time I use “Surprise Me!” on my Pocket phone app, I am quite happy with the result. It will work for you too!

Organize stuff with useful tags

In the old times, my collection of articles was a mess of random web pages. Now, the Pocket has tags and they made organization so much easier. There are many ways to implement tags, but it is not good to use too specific. With too many options to choose from, saving will stop being friction-less. If it takes more than a second to select a tag, collecting process becomes to much hassle. Introduce a few tags accurate enough to define the frame for the entire collection. Everything else can be easily found with search.

For quite a while, I just used productivity and leadership, as two main categories. Recently, I added minimalism. For example, reading list tag is for book reviews and recommendations. It became my someday/maybe list of things that I want to read in the future.

It is free, check it out

If you like to read and at the same want to keep high level of content organization, you might want to test Pocket. It provides reasonable balance between simplicity and usability. The free version offers enough features to satisfy the needs of most users. Give it a shot.

Photo by Maliha Mannan on Unsplash.

Running the boroughs of New York City

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Looks like in the context of running 2019 will be huge! I was drawn for the BMW BERLIN MARATHON 2019. It was my second attempt. I applied to start in 2018 without luck. This time over, I got in and on September 29th, 2019 with about 50000 other runners we will jam the streets of Berlin.

This means that upcoming nine months will be filled with a lot of training. Meanwhile though, I thought that it would be nice to walk down the memory lane and tell you about the most amazing running experience I had so far: The New York Marathon. This post is based on journal entries written on the next day after the marathon. So, it was cold and rainy Sunday, November 5th, 2017…

Before the start

The emotions were high and the adrenaline level was enormous. My plan was quite simple. I wanted to run at 4:30, I felt for 4:30 and, after the Wroclaw marathon two months earlier, I had a vague idea how to make it. What I did not take into account were the New York bridges and nasty uphill parts that devastated most amateur runners, including myself… but let’s start at the beginning. On Sunday, very early in the morning.

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My runner’s set. Everything was ready and waiting in the evening the day before. Everything was possible thanks to the substantial support of my alma mater – the Wroclaw University of Science and Technology.

To get to the starting line on time I had to get up at 5:00. Just in time to bite something and jump on the subway at 6:00. Twenty minutes later I was at the ferry terminal from which the ferry to Staten Island was departing every couple of minutes, taking hundreds of runners right to place where the race shall began few hours later. The famous orange ferries were not only the most convenient way of getting to the starting line, but also very photo-attractive. They carried people next to the Statue of Liberty and we were all able to admire the morning panorama of lower Manhattan. At the other side, all runners were directed to the buses going to Fort Wadsworth, where all runners needed to wait for their turn. Logistics and flow management of 60,000-70,000 people takes time, so even though I was on the ferry at 7:00, I got off the bus quite late, at about 9:00. It didn’t really bother me much. My start was scheduled at 11:00 and the alternative to that long ferry/bus ride was just standing in cold rain for additional couple of hours. Not fun.

In the waiting zone spirits were high. People seemed excited, still the tension was leaking everywhere. Five, maybe six helicopters overhead shook the atmosphere (NYPD, media …). Free coffee, bagels, energy bars and hundreds of toi-tois were available on demand. If someone needed some help to relax before the start, there were therapeutic dog booths here and there. There was a lot of time to talk to other runners and meet some interesting people.

The runners were divided into three groups (Blue, Orange, Green), which started in successive waves (Wave 1-4) . For order, each Wave was placed in six separate corrals (A-F). I gave up my bag of clothes (stashed for picking up after the run). and found myself with a pack of other runners at the start of Blue Wave 4 in Corral D. At the right moment, the wave (all corrals) approached the starting line. The anthem, the cannon shot … and we went!

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Excited crowd on the Verrazzano-Narrows Bridge.

All the way to Manhattan

The run took off calmly. It takes time to get into proper rhythm and Verrazano-Narrows Bridge was perfect for such warming up. The first few miles were rather quiet, because there was no cheering on the bridge. The helicopters were flying overhead. People took pictures of themselves and vigorously pushed forward. The crowd was quite dense, so I used this first bridge establish my pace. For this I used the paper pace calculator on my wrist. It was just a strip of paper with printed times and distances necessary to follow in order to finish the run in 4:30. It was a nice idea, but it was calibrated in miles, so coming from Poland I was initially a bit confused. Fortunately,  before the bridge was over, I found myself another runner to follow. He was wearing a t-shirt from some club of blood donors and ran perfectly steady for 4:35. For the first hour we went head to head. Unfortunately, after the fifth mile, in the middle of Brooklyn, he decided to go for a technical break (pee) and that was the last time I saw him.

In the meantime it started to rain…

At this point, I have to mention the cheering, which was simply sensational in Brooklyn. Crowds, crowds, crowds. Screaming, chanting, giving high-fives, playing music. The support method changed gradually. Details varied depending on which part of Brooklyn we were in. At Greenpoint, of course, we were welcomed by Polish flags and Polish music. Throughout the route, people shouted, served on their own food, bananas or other sweets. In general, the media estimated the number of supporters to be above one million.

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Green, narrow, and crowded streets of Brooklyn.

The idyll lasted until the Pulaski Bridge, which led us to Queens. Up to 25 km I was running steadily for 4:30. Well, maybe  a little faster, because I wanted to earn couple of  minutes to spare later. I expected to lose them anyway in the last kilometers of the race. After losing my first running partner (the blood donor), I found in the crowd a girl named Jessie. She ran for approx. 4:20, almost exactly as I needed. The plan was good and it worked until the Queensboro Bridge. At this point, I slowed significantly. Unfortunately, Jessie did not manage to keep up the pace as well. That was how I lost my second pacemaker. I managed not to stop running, but at the bridge hundreds of people gave up and started to walk. The slope was really challenging.

Suddenly, we found ourselves in Manhattan. Seventeen kilometers (and some) to the finish line. Time was around 2:11…

Hitting the wall…

It is different for different runners, but for most of amateur marathoners the real challenge starts at approx. 25-26th kilometer. It is the moment where the infamous wall hits. In New York my grit was tested right at the Queensboro Bridge and afterwards. Fortunately, the Queensboro Bridge took us to Manhattan giving the so desired motivation. The finish line seemed to be so close! You can see on the map that the bridge is next to the 60th street, so exactly on the same block on which the finish line is located. But it was not the end yet! Right after the bridge, the route took a sharp turn and took us north along the 1st Ave. The wall felt terrible, but the cheering of the crowds here was overwhelming. People were holding motivating signs or wearing big pictures of their favorites printed. You could hear cow bells. The signs saying “go on random stranger!” were really inspiring. It was really needed support, because right after the Queensboro, we had to run 75 blocks north (all the way to the 135th), through the next bridge, to Bronx!

On the 1st Ave I began gradually loosing my strength. My average rate decreased from 6:08 per kilometer to 6:30. It was still raining. At the 18th mile there was a little surprise in the form of a fire in the building adjacent to the marathon route. Although the situation was taken under control very quickly, part of the marathon route was occupied by a fire brigade and a very distinct stench of burning was hanging in the air. The organizers approached the matter very seriously and informed the runners well in advance about the situation on the route. I got a message and an e-mail when I was running through the Queensboro Bridge, that at about 18th mile there is “temporary obstruction” and that I should be ready for a break on the run! Fortunately, no one stopped us.

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Towards Upper Manhattan and Bronx.

Willis Ave Bridge which led us to Bronx was not as murderous as Queensboro, but my legs felt it anyway. I entered the phase when running is no longer purely  physical challenge but also the mental one. “I can, I can, I can do it …”, “go, go, go …”. It got even darker because of dense clouds. Despite everything, I ran through Bronx fairly quickly. Someone handed me sweets, and someone else gave me a high-five with hand smeared with cold balm for muscle pain (brilliant idea!). Desired moment of relief.

We needed to return to Manhattan, yet one more bridge was waiting for us. Some guy stood next to it, holding a hand-written sign saying “the last damn bridge!”, to which everyone reacted with laughter and applause. The final fight began at the last five miles, when we ran into the famous 5th Avenue. Especially in one particular location, at about 38 km, where the Central Park begins. There is a small but long ascent. On the distance of about one and a half kilometers, the elevation raises over 20 meters! Normally it should not be a difficult challenge, but after four hours of running in the rain the conditions are no longer normal. It started at the height of 102nd street, and the ground slowly raised all the way until the 60th street. Along the Fifth Avenue, my pace has dropped to more than 7:00 per kilometer. I lost all extra minutes I had earned earlier, and then some. From 4:30, it pushed me to 4:45.

The finish line was about there. The rain was heavy, shoes were soaked, clothes were soaked, my glasses needed wiping every few minutes, and the finish was not there. We turned into the 60th street, then another turn and, finally, the finish line… but first, the last 400 meters were sharp uphill! But this was the last surprise hurdle, and then … success, joy, and a happy ending to this story!

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The next day, the New York Times posted a list of finishers. Here I am!

 

The next Top 500 Innovators’ networking event is coming! Save the date!

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Panel discussion during the Top 500 Innovators (Stanford 2012) reunion in Poznan.

Several weeks ago our group of Top 500 Innovators Alumni conducted a little reunion. It has been six years since our group of forty researchers and technology transfer experts was sent to California to study scientific management and commercialisation at Stanford University. It was an amazing experience, and we gained a lot of practical skills there. I mentioned a few in this post.

The more I think about it, the more I see that the most important result of our stay in the USA is the network that we formed. Six years have passed. We all got older (hopefully wiser) and many of the bonds that we developed in Palo Alto are still strong. Our little reunion in Poznan felt like family gathering during Christmas!

Academics are a very interesting tribe. Entrepreneurs value networking as an important skill and tool. By comparison, academics are (on average) shy, quiet, introverted, and prefer to schmooze with other academics from similar fields of expertise. Contrary to entrepreneurs, scientists often need to be convinced that reaching towards a wider audience offers some value.

The truth is: networking as a scientist is neither simple nor easy. The language of science is not exactly inclusive and demands a lot from listeners. Journal articles are not that easy to read and understand. Keynote speeches at conferences are often difficult to comprehend (still easier than papers). Unfortunately, innovation and modern scientific development thrives on interdisciplinary networks that reach beyond the twisted corridors of the ivory tower.

We must learn how to network, network extensively, and most importantly network effectively. The best institutionalised examples of networks are the COST Actions, but there is a tactic suitable for everyone. The books and experts always advise to keep in touch with peers. All the time, not only when they are needed for something. Sounds like an introvert’s worst nightmare, but is it really that hard to pay a visit from time to time, eat lunch, or just make a call? For those who need some encouragement, there are also networking events…

Perhaps this is why I am so excited about the next Top 500 Innovators’ Meet-Up that will take place in May 2019 in Wroclaw. It will not only be an occasion to see all those friendly faces, but also and opportunity to strengthen and expand our network.

With a group of friends we are about to form the organising committee and create the framework for a two-days event aimed at researchers, entrepreneurs, and technology transfer experts. You don’t have to be the member of the Top 500 Innovators Alumni in order to participate and benefit from keynotes, workshops, and dinner table discussions. With a bit of luck some new unexpected areas for collaboration might emerge.

Save the date May 9-10th, 2019 and stay tuned. We will let you know more soon!

The most desired qualities of academic leaders

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I am exploring the topic of leadership for almost 6 years now, roughly since the Top 500 Innovators training at Stanford University that our group took in 2012. We were taught then how important the effective leadership is for the success of any organization, in that case of universities and similar research institutions.

The concept of leadership cannot exists without people, and I am lucky to work closely with a group of smart and dedicated students. They taught me that my actions and behavior can indeed influence their activities, performance and sometimes even mood. It was humbling, and over time, I understood how much more there is to learn and practice…

It is hard not to notice that the internet is flooded with leadership advice aimed at entrepreneurs. Thing is, even though academia is a bit different from the business environment, it still needs to embrace challenges of the modern world and apply suitable leadership practices. I look at trends and challenges of leadership, especially in the context of youngest generations, but there are hundreds of posts and articles being published on this topic every single day. It is just counterproductive (and impossible) to read everything.

Earlier this year Google updated its list of 10 behaviors that characterize best managers. There are so many lessons on this list to be learned by scholars. Especially those working closely with or supervising other researchers. Let’s discuss this list in the context of academic leadership.

Academic Leader…

Is a good coach

Being a research supervisor means that you have an knowledge that you share to the benefit of your students. Good mentor knows his expertise and stays within his competences. It is important to stay away from giving advice in areas that you have no prior experience. You might look competent on the short run, but the truth will always surface. This is not the way to build trust in the team.

To support a research team, it is necessary to understand that everyone has different needs and expectations. The only way is to find out how your team members work best, and adjust your coaching to match their work style. This requires to develop empathy to understand when the team need to be nurtured, and when it needs to be pushed towards the desired goal.

Empowers team and does not micromanage

Empowering sounds simple, but it is tricky. In reality it is often difficult to let go and allow others to think for themselves. After years of working in trenches, the transition to supervising position is challenging. Not everyone finds the new role enjoyable, as it usually means less hands-on research, more meetings, and much more administrative tasks.

Becoming leader in academic environment requires getting rid of the whole I-can-do-it-better mindset. Empowerment means that young researches need to be allowed to make their own decisions and take responsibility for these decisions. This demands substantial degree of trust and willingness to share valuable information. Great mentors know that information empowers, while the lousy ones think that sharing undermines their position. Truth is, only if young researchers will be allowed to fail, they will learn from their own mistakes and produce above average results. So, no more ready answers and no more micromanaging.  Empowering, just like leadership, is a skill and like every other skill it can be learned and practiced. So, there is hope for all of us.

Creates an inclusive team environment, showing concern for success and well-being of all members

Progressing towards PhD title is often stressful and lonely endeavor. Thing is, the most effective research is done in a collaborative environment. The group can support themselves and find solutions to individual member’s problems. It is now generally accepted that sparks of creativity most often fly in diverse groups. That is why many top world universities, including Stanford and UC Berkeley, made collaboration and team work very important part of their curriculums.

There are various ways to create inclusive academic environment. It is important to get to know team members a bit better on personal level. Flexibility with regulations and deadlines is also recommended, for example allowing working from home if necessary (actually, unless you need a lab, this is not a big deal in scientific research). Encourage collaboration between team members, for example facilitate teaching substitutions or help them working together on some small research project.

Is productive and results-oriented

Daily survival in academic environment is especially challenging for people without clear goals and laser-like focus.

Various dangers lurk around corners, awaiting everyone about to embark on a journey towards a PhD degree. Working on thesis can quickly take a student on an endless voyage towards the horizon of knowledge. The more she knows, the more she finds to learn, study, and understand. It is so easy to lose the way. At the same time, a scientist must avoid focusing solely on “the next paper” or “the next report” and keep an eye on larger goals (like writing thesis). The research is done for a purpose, and it is not wise to forget what this purpose it.

The guidance is especially valuable here, as the supervisor is often the one looking and at the compass and steer the research in the right direction. Pushing towards doing the right things.

Is a good communicator — listens and shares information

Staying silent and listening allow other people to share information about their work issues, and sometimes even their personal life. Being good at listening increases ones trustworthiness, and at the same time helps to gather information. This is important because it is impossible to direct young researchers effectively without understanding of their situation and needs.

Only a fool mentor will rush in and start speaking and acting without discernment. Yet, I find this the most difficult skill to develop. Shut up and listen.

Supports career development and discusses performance

Many young researches do not know what is expected of them at work. They need a clear direction on what is expected of them, how much and when. They need to be held accountable for results and should be provided with regular feedback on their performance. They need supervisors that are approachable, responsive, and  available whenever mentee needs some support.

An academic leader should be a role model and mentor. The long-term relationship between research supervisor and his mentees means that he will have substantial influence on their career development. It is not only about honing research skills. It is also about explaining nuances of academic life. It requires frank and direct conversations about long-term aims, as well as short-term performance.

Has a clear vision/strategy for the team

It is just impossible for a PhD student to start with a clear well-thought career and research plan. This is a job of his research supervisor. Student might have some plans and expectations, but usually their understanding of academic reality is rather vague. So he needs to rely on advice of his older peers.

Great leader is focused on the future looking for potential opportunities for his team. He plans research, dissemination, collaboration and, at the same time, develops his team in order to prepare it for upcoming opportunities.

Has key technical skills to help advise the team

One cannot drive the research team without fundamental understanding of the studies being done. True, after several years the competency level of a PhD student on a particular topic might exceed his supervisor’s. Still, collaboration and effective leading are possible only if both sides understand each other needs and expectations. What I found, this puts quite a burden on the supervisor, who needs to improve his expertise constantly in order to keep up with his team. Especially, if he works with a group of PhD students carrying on different research projects.

Collaborates across Google Faculties

Academic environment is very rigid. Quite often, interaction is limited and the level of secrecy between research teams is high, especially between groups studying similar topics. Academic leaders need to focus on building agile and energized research networks. The times of science cultivated in solitude are over.

Unhealthy competition between research groups prohibits collaboration and advancement. It is not easy to bulid rapport and establish trust between teams, but in the long term, this might be only way to ensure progress in XXI century.

Is a strong decision maker

Any significant progress requires action, and action always follows a firm decision. Academic environment is especially susceptible to procrastination that expresses itself in unending ongoing research. Endless studying is very addictive, and it is as bad as perfectionism.

This is one of the reasons why it is so difficult to establish effective collaboration between business and academic environments. Time seems to be an unlimited resource at universities, there is no harm in one more read paper or one more conducted experiment. At the same time, entrepreneurs desire quick and correct answers, here and now. They cannot afford waiting.

This is why academic environment, now more then ever, would benefit from convinced leaders capable of making competent and strong decisions. Academia no longer has luxury of being slow and perfect. I do not necessarily appreciate that fact, but the world changes very fast nowadays, and the only way for us is to adapt.

Photo by rawpixel on Unsplash.

Two extraordinary books that impressed me this summer (and will delight you too!)

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Summer holiday is always a good opportunity to catch up on some reading. Indeed, I read a few good books during summer months, but there were two exceptional ones that really resonated with me. I would like to share them with you.

Olga Tokarczuk’s “Bieguni” (“Flights”)

“Bieguni” is not really a new book. Published first in 2007 and awarded with the Nike Award in 2008 was recently brought back into spotlight. Translated to English, it was awarded in 2018 with the Booker Prize, a literary prize awarded each year for the best original novel written in the English language and published in the UK. I read the Polish original, but many critiques and reviewers say that the translation is similarly exceptional.

“Bieguni” (“Flights”) takes you on a journey along with mystery travelers. The book is  named (the original title) after a fictional sect of Slavic nomads who endlessly wander the planet. It tells stories about people from different times and places. The theme is travel, and the only constant here is continuous movement from place to place. Sometimes to unexpected spots far away from the beaten tracks, to dark corners of human soul, right next to twisted secrets of human existence. It is a captivating novel with distinct philosophical flair.

The stories are enchanting and intense. The characters are unique and special, driven by strange desires and hidden motivations are looking for answers in different times and places.

Those who spent their time at various airports will quickly identify and feel belonging to the constantly moving anonymous passing crowd. And right then, just after takeoff, the novel will grab and take you to some time and far away place to just to unfold yet another narrative. A must read.

Yuval Noah Harari’s “Homo Deus: A Brief History of Tomorrow”

Compared to the above mentioned book, this one belongs to completely different category. After several days of dreamy spiritual journeys, “Homo Deus” was a return to the world of science, knowledge, and reason. A sequel to Harari’s global bestseller “Sapiens” is in many ways worthy continuation to the awarded predecessor.

Chances are that you know other Harari’s masterpiece “Sapiens”. The book unveils the story of evolution and complicated history of humanity. “Homo Deus” takes the discussion even further. Using philosophy, history, sociology, in combination with the latest technological advances, Harari looks for the answer what might happen to us in the future. This is a challenging task because according to the author in the 21st century might bring the most profound change in the history – we might finally evolve beyond limitation of our minds and bodies. Will we achieve eternal life? Or rather, who will belong to the privileged cast of immortals? Undoubtedly our societies will change, religions will have to adapt to the new situation. Will the emerge of AI change everything? Those are only a few of many interesting problems discussed in this brilliant educating book.

And one final recommendation. My wife, who also finished this book few weeks ago, said that reading it was like spending an enjoyable evening with a wise friend who makes sure that you have great time and makes you feel smarter. I think this is the best summary of “Homo Deus”. Get a copy, make a tea, and find yourself.

I can’t do justice to these books, so to learn more take a look at much deeper and detailed reviews here and here.

Graphene oxide nanofluids in a two-phase closed thermosyphon

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Graphene oxide nanofluids, before (brownish) and after the experiment

One of the most interesting things that we are studying in our research group are thermal effects related to nanofluids. The research is conducted by Agnieszka Wlaźlak (@aga_wlazlak), a PhD student at the Faculty of Mechanical and Power Engineering, Wroclaw University of Science and Technology, Poland. It is organized in collaboration with Prof. Matthias H. Bushmann from the Institut für Luft- und Kältetechnik, Dresden, Germany, and Michal Woluntarski from the Institute of Electronics Materials Technology, Warsaw, Poland.

Heat transfer and nanoparticles

In general, heat transfer improvement methods can be classified in one of two categories: active (e.g. application of external energy) and passive (e.g. modifications to the surface area, influence of the flow, or enhancement of fluid properties with various additives). In our most recent paper we focus on the last of above-mentioned passive methods: the introduction of nanoparticles that improve thermal properties of the base heat transfer fluid.

Why nanoparticles? Well, prior to nanomaterials, attempts were made to create sustainable suspensions with micro-particles. The underlying idea was very simple – if we add some solid material to the liqud substance, we could potentially improve specific heat and thermal conductivity of the latter. Unfortunately, micro-particle solutions did not reach expectations due to their poor stability and tendency for clogging of channels, which noticeably increased pumping power. The situation is different with nanoparticles. Using nano- instead of microparticles seems to be a promising solution to almost all rheological problems. Resulting suspensions are now commonly called nanofluids. Significant amount of research on nanofluids is currently conducted in many labs around the world.  In Europe, many of the research groups collaborate within the NANOUPTAKE COST Action network. We are proud members of this action and the results presented in this particular work are a direct result of this collaboration. If you want to know more, not that long ago I have written another post about COST Actions and their advantages.

What are thermosyphons?

Thermosyphons are sealed tubes filled with some kind of working fluid. The fluid inside is usually chosen depending on desired operating conditions, and once the device if filled with proper substance, it becomes a passive heat transfer device. Every thermosyphon consists of three distinct sections: evaporator section, adiabatic section, and condenser section. Working fluid boils due to heat supplied to the evaporator from the external source. Vapor flows through the adiabatic section to the above-located condenser section where heat is released to the cooling medium. Condensed liquid then returns to the evaporator section due to gravity. Heat transfer capabilities of thermosyphon are limited by thermodynamic properties of the fluid inside. No wonder why so many researchers are now attempting to improve those properties with various types of nanoparticles.

The main purpose of using nanofluids in thermosyphons is to lower overall thermal resistance of the device below what is possible with a pure working fluid. For such a simple device, the process is quite complex because it involves many different kinds of heat transfer. Only a few hypotheses how nanoparticles influence thermosyphon operation can be found in the literature, e.g. enhanced thermal properties of nanofluids, nanoparticle interaction with the heater surface, and altered boiling process. It is now commonly agreed that all the effect is localized in the evaporator section. It was confirmed that nanofluids do not affect the thermal behaviour of the condenser.

Our study

In our latest paper (full text available since today as Open Access) we look into the performance of graphene oxide (GO) nanofluids in a sealed thermosyphon. We focused on three factors that influence operation of the two-phase closed thermosyphon: deposition of nanoparticles on the heat transfer surface, occurrence of geyser boiling, and the influence of surfactants.

Geyser boiling is a kind of instantaneous boiling where the working fluid gathered above a growing bubble in evaporator section is violently propelled up to the condenser section. This energy build-up is similar to what happens in a typical geyser, hence the borrowed name. This sometimes loud and rather unstable phenomena reduces the amount of liquid in the evaporator section, thus decreasing its heat transfer capacity and, as a consequence, diminishes performance of the thermosyphon.

In the study, firstly, we determined to what degree GO nanofluids affected thermal resistance of the thermosyphon and how the presence of surfactant (sodium dodecyl sulphate) impacted its operation. Secondly, we studied the influence of boiling process on the medium-term stability of GO nanofluid and deterioration of GO nanoparticles. The photograph above shows what happens to GO nanofluid (clean brown-insh liquid) after several cycles of use inside the thermosyphon. Graphene nanoparticles agglomerated forming easily visible micro-scale clusters. Such fluid is no longer stable and is not really suitable for further use.

Finally, we analysed the occurrence and consequences of geyser boiling in the thermosyphon. We used especially located high-resolution pressure gauges that allowed us to register and record any occurrences of geyser boiling. The influence of boiling process on graphene oxide flakes was studied using SEM photography of particles that remained in the working fluid after the experiment.

There are several detailed conclusions in the paper, for example we found that:

  • GO nanofluids improve heat transfer capabilities of the thermosyphon but the effect is noticeable only at low temperatures of the evaporator section.
  • Heat transfer improvement is caused by the deposited layer on the inner surface of the evaporator. The layer affects not only the roughness but also the surface energy, wettability, and surface tension at the evaporator wall.
  • The surface chemistry of GO nanoparticles plays a key role in avoiding geyser boiling. Even though the graphene oxide nanofluid was stabilised with SDS, it did not prevent geyser boiling because most of the SDS was attached to the surface of the GO flakes. In result, there was not enough surfactant in the solution to supress geyser formation.

Several more conclusions and the entire leading discussion are presented in the paper itself.

Also, I am happy to say that the work presented above is just the beginning, as further study is already underway. In 2017 Agnieszka obtained a research grant (PRELUDIUM 12) from the National Science Center (NCN) and become Principal Investigator leading the project entitled “Heat transfer enhancement due to interaction of nanoparticles with evaporator surface during boiling of nanofluids in a thermosyphon”.

Source

  1. Wlazlak, A., Zajaczkowski, B., Woluntarski, M. et al. Influence of graphene oxide nanofluids and surfactant on thermal behaviour of the thermosyphon, J Therm Anal Calorim (2018). https://doi.org/10.1007/s10973-018-7632-x

What students and academics can learn from the greatest Polish athletes

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Storm clouds gathering above the Olympischer Stadium in Berlin during evening session of the European Athletics Championships

What an unbelievable success! Polish athletes showed in the last few days truly inspiring and motivating performance.

They taught us important life lessons on grit, determination, and hard work. Something we all can use, whether we are students, academics, or just human beings looking for inspiration. They showed us what high performers in any discipline need to understand to reach the highest level of skill and grab the prize.

Hard training

One of Polish newspapers had this headline: “many of the winners might not be well known, but they were surely working very hard.” Well. They are known now! The way how Paulina Guba (shot put) bravely reached and grabbed the title of European Champion will make everyone to remember her name!

Such success would not be possible without hours and hours of focused deliberate training. No one can win without proper skill, and to gain this level of skill it is necessary to clock enough hours first. Some say it is 10000, some claim it is more. The lesson is clear, you can’t get to the top unless you roll up your sleeves and work harder. The result? Just look at Justyna Swiety-Ersetic. On Saturday, she won gold medal and European Championship running 400 m, at the same time setting up her new personal best time. If this was not spectacular enough, less than two hours later she beautifully finished 400 m relay and won for her team another gold medal.

Well-thought-out strategy

Success is not only about skill and speed. To become master you need a good strategy. It is impossible to win 800 m finals a without a clear plan when to attack, when to save energy, when to hide, and when to pass your opponents. Down to every second. This is how Adam Kszczot became European Master third time in a row. His friends, his opponents, media, everyone calls him “the Professor”. Also, now you know why this story belongs to an academic-themed blog.

A bit of luck is also important

In the end, this is a still a competition. Very fierce one. Sometimes pure luck, an opponent’s mistake, random push, or even a second of doubt can cost you your precious advantage and ultimately lead to your defeat. There are some factors during the execution of your plan that you just can’t control.

Failure is always an option. Sometimes, passing a baton during relay will not go smooth enough and precious seconds will be lost. Sometimes, opponent will elbow you, and you lose your rhythm. What matters is how you fight despite the obstacles, and our athletes were fighting hard.

Congratulations! Thank you for the inspiration! Thank you for the motivation! You made us all proud! Chapeau bas!