Every summer, my family and I travel across the world, 3,000 miles away to the culturally diverse country of India. Now, India is a country infamous for its scorching heat and humidity. For me, the only relief from this heat is to drink plenty of water. Now, while in India, my parents always remind me to only drink boiled or bottled water, because unlike here in America, where I can just turn on a tap and easily get clean, potable water, in India, the water is often contaminated. So my parents have to make sure that the water we drink is safe.
Svakog leta, moja porodica i ja putujemo preko pola sveta, na udaljenost od skoro 5 000 kilometara, u kulturološki raznoliku zemlju Indiju. Indija je zloglasna država zbog svoje vreline i vlažnosti. Za mene je jedini spas od ove vreline u tome što pijem dosta vode. Ali dok smo u Indiji, roditelji me uvek podsećaju da pijem samo prokuvanu ili flaširanu vodu, jer za razliku od Amerike, gde mogu samo da odvrnem česmu i dobijem čistu vodu za piće, u Indiji je voda često zagađena. Stoga moji roditelji moraju da provere da je voda koju pijemo bezbedna.
However, I soon realized that not everyone is fortunate enough to enjoy the clean water we did. Outside my grandparents' house in the busy streets of India, I saw people standing in long lines under the hot sun filling buckets with water from a tap. I even saw children, who looked the same age as me, filling up these clear plastic bottles with dirty water from streams on the roadside. Watching these kids forced to drink water that I felt was too dirty to touch changed my perspective on the world. This unacceptable social injustice compelled me to want to find a solution to our world's clean water problem. I wanted to know why these kids lacked water, a substance that is essential for life. And I learned that we are facing a global water crisis.
Međutim, ubrzo sam shvatila da nemaju svi tu sreću da uživaju u čistoj vodi kao mi. Ispred kuće mojih deke i bake u prometnim indijskim ulicama, videla sam ljude koji stoje u dugim redovima na vrelom suncu i pune kante vodom sa česme. Videla sam čak i decu, koja su izgledala mojih godina, kako pune plastične boce prljavom vodom iz potoka kraj puta. Posmatranje ove dece koja moraju da piju vodu koja se meni činila previše prljavom da je dodirnem je promenilo moj pogled na svet. Ova neprihvatljiva društvena nepravda me je naterala da poželim da nađem rešenje svetskog problema nedostatka čiste vode. Želela sam da znam zašto ova deca nemaju čistu vodu, supstancu koja je neophodna za život. Shvatila sam da se susrećemo sa globalnim krizom nedostatka vode.
Now, this may seem surprising, as 75 percent of our planet is covered in water, but only 2.5 percent of that is freshwater, and less than one percent of Earth's freshwater supply is available for human consumption. With rising populations, industrial development and economic growth, our demand for clean water is increasing, yet our freshwater resources are rapidly depleting. According to the World Health Organization, 660 million people in our world lack access to a clean water source. Lack of access to clean water is a leading cause of death in children under the age of five in developing countries, and UNICEF estimates that 3,000 children die every day from a water-related disease.
Ovo vas može začuditi, jer je 75% naše planete prekriveno vodom, ali samo 2,5% toga je slatka voda, a manje od 1% slatke vode je dostupno za ljudsku upotrebu. Uz populaciju koja se povećava, industrijski razvoj i ekonomski rast, naša potreba za vodom se uvećava, ali se naše zalihe slatke vode ubrzano troše. Prema podacima Svetske zdravstvene organizacije, 660 miliona ljudi na svetu nema pristup čistoj vodi. Nedostatak čiste vode je glavni uzrok smrti među decom mlađom od pet godina u zemljama u razvoju, a UNICEF procenjuje da oko 3 000 dece svakodnevno umru od bolesti koje se prenose vodom.
So after returning home one summer in eighth grade, I decided that I wanted to combine my passion for solving the global water crisis with my interest in science. So I decided that the best thing to do would be to convert my garage into a laboratory.
I tako, vrativši se kući jednog leta u osmom razredu, odlučila sam da želim da spojim svoju strast za rešavanjem globalne krize nedostatka vode sa svojim zanimanjem za nauku. Odlučila sam da bi najbolja stvar koju bi mogla da uradim bilo da pretvorim garažu u laboratoriju.
(Laughter)
(Smeh)
Actually, at first I converted my kitchen into a laboratory, but my parents didn't really approve and kicked me out.
U stvari, prvo sam pretvorila kuhinju u laboratoriju, ali se moji roditelji nisu baš složili i isterali su me.
I also read a lot of journal papers on water-related research, and I learned that currently in developing countries, something called solar disinfection, or SODIS, is used to purify water. In SODIS, clear plastic bottles are filled with contaminated water and then exposed to sunlight for six to eight hours. The UV radiation from the sun destroys the DNA of these harmful pathogens and decontaminates the water. Now, while SODIS is really easy to use and energy-efficient, as it only uses solar energy, it's really slow, as it can take up to two days when it's cloudy. So in order to make the SODIS process faster, this new method called photocatalysis has recently been used.
Takođe sam čitala dosta istraživačkih radova o vodi i otkrila da se trenutno u razvijenim zemljama nešto pod nazivom solarna dezinfekcija ili SODIS koristi za pročišćavanje vode. Čiste plastične boce se napune zagađenom vodom i onda ostave na suncu šest do osam sati. Sunčevo UV zračenje uništava DNK ovih štetnih patogena i čisti vodu. Iako je SODIS zaista jednostavan i štedi energiju time što koristi samo solarnu energiju, veoma je spor, jer proces može da potraje do dva dana kada je oblačno. Kako bi se ubrzao proces, novi metod pod imenom fotokataliza se od nedavno koristi.
So what exactly is this photocatalysis? Let's break it down: "photo" means from the sun, and a catalyst is something that speeds up a reaction. So what photocatalysis is doing is it's just speeding up this solar disinfection process. When sunlight comes in and strikes a photocatalyst, like TiO2, or titanium dioxide, it creates these really reactive oxygen species, like superoxides, hydrogen peroxide and hydroxyl radicals. These reactive oxygen species are able to remove bacteria and organics and a whole lot of contaminants from drinking water.
Dakle, šta je tačno fotokataliza? Rastavimo je u delove: „foto“ znači da dolazi od sunca, a katalizator je nešto što ubrzava datu reakciju. Dakle, fotokatalizator samo ubrzava proces solarnog pročišćavanja vode. Kada se pojavi sunčeva svetlost i dosegne fotokatalizator, kao što je TiO2 ili titanijum-dioksid, on stvara veoma reaktivne vrste kiseonika poput superoksida, hidrogen-peroksida ili hidroksil radikala. Ove reaktivne vrste kiseonika mogu da uklone iz pijaće vode bakterije, organska jedinjenja i veliki broj drugih zagađivača.
But unfortunately, there are several disadvantages to the way photocatalytic SODIS is currently deployed. See, what they do is they take the clear plastic bottles and they coat the inside with this photocatalytic coating. But photocatalysts like titanium dioxide are actually commonly used in sunscreens to block UV radiation. So when they're coated on the inside of these bottles, they're actually blocking some of the UV radiation and diminishing the efficiency of the process. Also, these photocatalytic coatings are not tightly bound to the plastic bottle, which means they wash off, and people end up drinking the catalyst. While TiO2 is safe and inert, it's really inefficient if you keep drinking the catalyst, because then you have to continue to replenish it, even after a few uses.
Nažalost, postoji nekoliko mana načina na koji se fotokalizatorski SODIS trenutno upotrebljava. Oni uzimaju prazne plastične boce i oblažu unutrašnjost tom fotokatalizatorskom oblogom. Ali neki od fotokatalizatora poput titanijum-dioksida se često koriste u kremama za sunčanje da blokiraju UV zračenje. Tako da kada unutrašnjost boca obložimo njima, u stvari blokiraju jedan deo UV zračenja i smanjuju efikasnost procesa. Takođe, ova fotokatalitička obloga nije tesno pripijena uz plastičnu bocu, što znači da otpadne i ljudi na kraju popiju sam katalizator. Iako je TiO2 bezbedan i inertan, zaista je neefikasno ako kontinuirano pijete katalizator jer onda morate da ga dopunite posle svega nekoliko upotreba.
So my goal was to overcome the disadvantages of these current treatment methods and create a safe, sustainable, cost-effective and eco-friendly method of purifying water. What started off as an eighth grade science fair project is now my photocatalytic composite for water purification. The composite combines titanium dioxide with cement. The cement-like composite can be formed into several different shapes, which results in an extremely versatile range of deployment methods. For example, you could create a rod that can easily be placed inside water bottles for individual use or you could create a porous filter that can filter water for families. You can even coat the inside of an existing water tank to purify larger amounts of water for communities over a longer period of time.
Moj cilj je stoga bio da savladam mane ovih aktuelnih metoda i stvorim bezbedan, održiv, jeftin i ekološki način pročišćavanja vode. Ono što je počelo kao projekat za naučno takmičenje u osmom razredu je sada moja fotokatolizatorska smeša za pročišćavanje vode. Smeša je kombinacija titanijum-dioksida i cementa. Smeša na bazi cementa se može oblikovati u nekoliko različitih oblika, što dovodi do veoma raznovrsnih metoda za upotrebu. Na primer, mogli biste da napravite šipku koju biste lako stavili u bocu za ličnu upotrebu ili biste mogli da napravite propustljiv filter koji može da pročišćava vodu za porodice. Mogli biste čak da obložite unutrašnjost rezervoara za vodu da biste pročistili dovoljno vode za čitave zajednice tokom dužeg vremenskog perioda.
Now, over the course of this, my journey hasn't really been easy. You know, I didn't have access to a sophisticated laboratory. I was 14 years old when I started, but I didn't let my age deter me in my interest in pursuing scientific research and wanting to solve the global water crisis.
Tokom razvoja ovog projekta, moj put nije bio bez poteškoća. Nisam imala pristup opremljenoj laboratoriji. Imala sam 14 godina kad sam počela, ali me moje godine nisu odvratile od interesovanja za naučno istraživanje i želje da nađem rešenje za globalnu krizu vode.
See, water isn't just the universal solvent. Water is a universal human right. And for that reason, I'm continuing to work on this science fair project from 2012 to bring it from the laboratory into the real world. And this summer, I founded Catalyst for World Water, a social enterprise aimed at catalyzing solutions to the global water crisis.
Znate, voda nije samo univerzalni rastvarač. Voda je univerzalno ljudsko pravo. I zbog toga nastavljam da radim na ovom projektu iz 2012. godine kako bi dospeo iz laboratorije u stvaran svet. A ovog leta sam osnovala „Katalizator za vodu u svetu“ društveno odgovorno preduzeće čiji je cilj da razvije rešenja za globalnu krizu vode.
(Applause)
(Aplauz)
Alone, a single drop of water can't do much, but when many drops come together, they can sustain life on our planet. Just as water drops come together to form oceans, I believe that we all must come together when tackling this global problem.
Jedna kapljica vode sama ne može da učini puno, ali kada se združi mnogo kapljica, mogu da održe život na zemlji. Baš kao što se kapljice vode združuju da stvore okeane, verujem da svi mi moramo da se udružimo u borbi protiv ovog globalnog problema.
Thank you.
Hvala.
(Applause)
(Aplauz)
Thank you.
Hvala.
(Applause)
(Aplauz)