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Thermal decomposition of cornstarches with different amylose/amylopectin ratios (waxy: 0/100, maize: 23/77, Gelose 50: 50/50, and Gelose 80: 80/20) under nitrogen condition was investigated by thermogravimetric analysis (TGA). Various decomposition models including Friedman, Kissinger, Flynn‐Wall‐Ozawa, and modified Coast‐Redfern methods were used to determine the apparent activation energy of different starches. Fourier transform infrared spectrometry (FTIR) and TGA‐FTIR were also used to study the mechanism of thermal decomposition process. The results show a multiple‐step mechanism for the thermal decomposition of all cornstarches. The sequence of activation energy for the cornstarches is waxy>maize>G50>G80, which corresponds to amylopectin content. FTIR results confirm that the thermal decomposition of cornstarch is due to the long‐chain scission. The higher activation energy for cornstarch with higher amylopectin content can be explained by its higher molecular weight and more α‐1,6 bonds.

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We present a simple approach to realize truly random number generation based on measurement of the phase noise of a single mode vertical cavity surface emitting laser (VCSEL). The true randomness of the quantum phase noise originates from the spontaneous emission of photons and the random bit generation rate is ultimately limited only by the laser linewidth. With the final bit generation rate of 20 Mbit/s, the physically guaranteed truly random bit sequence passes the three standard random tests. Moreover, for the first time, a continuously generated random bit sequence up to 14 Gbit is verified by two additional criteria for its true randomness. [4]. Traditionally, pseudorandom number generator (PRNG) based on computational algorithms is adopted to generate random bits and is competent in many fields. However, it cannot produce truly random (unpredictable and irreproducible) bit sequence, and so may result in potential dangers in security related applications, say, in quantum cryptography [5]. Actually, the unconditional security of quantum key distribution can ONLY be guaranteed when a truly random number generator (TRNG), based on quantum mechanical process instead of the intractability assumption with classical algorithms [6], is available.Distinct from PRNG, a TRNG can only be realized by a physical way, instead of an algorithm-based way; however, a physical way does not sufficiently guarantee the true randomness. The physically random processes, such as radioactive decay [7], electric noise in circuits [8], frequency jitter of electric oscillator [9], and those based on laser (photon) emission/detection [10][11][12], can ensure the inability of pre-estimation on random numbers and so can be adopted as candidates to implement TRNG. In particular, those based on the detection of laser field attracted tremendous interests in recent decade.

A biobased poly(butylene 2,5-furan dicarboxylate) (PBF) is synthesized and blended with poly(lactic acid) (PLA). With only 5 wt % addition of PBF, the elongation at break of PLA becomes 18.5 times more than before, while the tensile modulus and tensile strength at yield keep almost the same. Morphological analysis based on scanning electron microscope pictures shows drastic shape deformation of PBF dispersed phases from sphere to fibril. The elongation ratio of PBF phase is much larger than that of PLA matrix, which is caused by a possible "plastic-rubber" transition in PBF during stretch process. On the other hand, stretch induced crystallization in PBF happened and it may increase the modulus of PBF along the tensile direction. Probably with the above two phenomena, PLA is dynamically toughened and strengthened in the elongation procedure. Moreover, the impact strength of the blends is better than those of the two pure components, and rubber-plastic transition and crystallization of PBF could improve the impact toughness too. The gas barrier property of PLA/PBF blends is also significantly enhanced by the introduction of a furan ring. It can be concluded that PLA/PBF blends are a good base material with great potential for future development in different areas.

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Multiphasic titanium dioxide (TiO2) possessing abundant heterophase junctions have been widely used for various photocatalytic applications. Current synthesis of multiphasic TiO2 mainly involves the process of thermal treatment and multiple steps of rigorous reactions, which is adverse to controlling the crystal phases and phase ratios of multiphasic TiO2. Meanwhile, the resulting products have relatively low surface area and nonporous structure. Here, a facile polymer‐assisted coordination‐mediated self‐assembly method to synthesize mesoporous TiO2 polymorphs with controllable heterophase junctions and large surface area by using polyethylenimine as the porogen in an acidic aqueous synthesis system is reported. Using this approach, the crystal phases (triphase, biphase, and monophase) and phase compositions (0–100%) are easily tailored by selecting the suitable acidic media. Furthermore, the specific surface areas (77–228 m2 g−1) and pore sizes (2.9–10.1 nm) are readily tailored by changing the reaction temperature. The photocatalytic activity of mesoporous TiO2 polymorphs is evaluated by photocatalytic hydrogen evolution. The triphasic TiO2 exhibits an excellent photocatalytic H2 generation rate of 3.57 mmol h−1 g−1 as compared to other polymorphs, which is attributed to the synergistic effects of heterophase junctions and mesostructure. The band diagram of possible electron transfer pathway for triphasic TiO2 is also elucidated.