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For the first time, the use of stannate-based sorbents was investigated as high temperature CO2 sorption to evaluate their potential to contribute towards reducing carbon emissions. The sorption capacity and kinetics of commercial tin oxide, sodium, potassium and calcium stannates and lab synthesised potassium stannates were tested using thermogravimetric analysis. Commercial K2SnO3 was found to possess the largest CO2 uptake capacity (2.77 mmol CO2/g or 12.2 wt%) at 700 °C, which is among the highest for potassium sorbents, but the CO2 desorption was not successful. On the contrary, the in-house synthesised K-stannate (K-B) using facile solid-state synthesis outperformed the other sorbents, resulting in a CO2 uptake of 7.3 wt% after 5 min, an adsorption rate (0.016 mg/s) one order of magnitude higher than the other stannates, and stability after 40 cycles. The XRD and XPS analyses showed that K-B contains a mixture of K2SnO3 (76%) and K4SnO4 (21%), while the Scherrer crystal sizes confirmed good resistance to sintering for the potassium stannates. Among the apparent kinetic model tested, the pseudo-second order model was the most suitable to predict the CO2 sorption process of K-B, indicating that chemical adsorption is dominant, while film-diffusion resistance and intra-particle diffusion resistance governed the sorption process in K-B. In summary, this work shows that solid-state synthesised potassium stannate could be an effective sorbent for high temperature separation, and additional work is required to further elucidate its potential.

Through our work, we have come to the conclusion that, if everyone who has a great idea and the entrepreneurial skills to bring it to life could operate on a level playing field-in other words, if entrepreneurship were more democratic-our society would be much better off.From the customer's perspective, a pedigree doesn't matter, but from an investor's perspective it often matters far too much. A top investment bank or consulting firm will care where you went to school and what your grades were, and your CV may determine whether a Fortune 500 company will "buy" your expertise. But these things won't matter to your customers-as long as you are giving them a great product or an outstanding service.We have learned the value of empowering entrepreneurs who have lived experience, and the competitive advantage this offers forward-thinking investors. Locating and supporting entrepreneurs with varied life experiences can lead to more successful companies. We believe that it can, in fact, lead to the development of products and services that the majority of people actually need and are asking for, rather than those that a small segment of investors think people want.This competitive advantage is particularly true with financial services technology, or the FinTech sector, where new ventures are more likely than those in other fields to be business-to-consumer enterprises. Many EdTech companies, for example, deal with schools and school boards or offer their services to major companies like Pearson. In the health sector, entrepreneurs are more likely to deal with hospitals or insurance companies than to be at a patient's bedside.FinTech is different. While there are certainly plenty of business-to-business financial services, many of the most innovative ventures deal directly with the consumer-investment advisor and money manager services, fraud protection, and, increasingly, alternatives to predatory check-cashing and lending companies. Therefore, the product seller and the product user are likely to have a stronger connection, due to their lived experiences. FinTech also addresses the needs associated with small businesses, which many aspiring entrepreneurs are familiar with.In this essay, we introduce a number of entrepreneurs from backgrounds and regions that traditionally have received too little investment, but who nevertheless

In 2009, Jen Medbery was a techie-turned-teacher with an idea to revolutionize American education, but she couldn't find funding to grow the company. After graduating from Columbia with a degree in computer science and working in the trenches as a classroom teacher-first through Teach For America, then as a founding member of a charter school in New Orleans-Jen grappled with a dilemma most teachers face today: the time-consuming task of gathering and tracking data. While using student performance metrics has been proven to improve education, particularly in underserved areas, it often demands a prohibitive amount of teachers' time. To help herself and her fellow teachers deal with this problem, Jen created a software program that she called Drop the Chalk. Based on feedback about the software, Jen decided to leave teaching to focus on developing Drop the Chalk into a mainstream solution for one of the major "pain points" in American education. She now had a product with great customer feedback and was making a significant impact, but she had few options for getting financial support or finding investors.In the salt flats of Gujarat, India, Rajesh Shah had been working with agariyas-salt farmers-for almost 30 years. Agariyas work in some of the most difficult conditions in the world. They work around the clock for eight months of the year, standing in 110-degree heat in the middle of the desert, pumping and raking saltwater until they can produce enough crystallized salt to sell. These farmers earn less than $1 per day, and must spend almost 50 percent of what they make on the diesel fuel to run their salt pumps. Perhaps most chillingly, when agariyas die and their bodies are cremated, their feet do not burn because they are so saturated with salt. After almost three decades working with the salt producers in various capacities, Rajesh had developed a concept called SABRAS, a for-profit company that could do two primary things: process and

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