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51.
射频感应耦合等离子体能够在室温条件下选择活化并分解二氧化碳,本文通过调控等离子体放电条件(气体流量、放电频率等)获得了较高的一氧化碳产率. 研究发现网状金属催化剂在二氧化碳等离子体中能促进氧原子的复合反应,从而有效抑制其与目标产物一氧化碳的逆反应,提升反应整体效率. 本文为实时转化过剩的可再生电能(来自太阳能、风能、潮汐能等)为高附加值一氧化碳中的化学能提供了一个可行的方案.  相似文献   
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Variants of two basic infinite games of perfect information are studied. A notion of continuous strategy for the playerS (Size) is shown to be related to a notion of convergence norm for sequences of reals. With each such norm, a variant of each of the basic games is associated in which the size player has to see that each play obeys the norm. Restriction to choose only rational numbers is also imposed onS. Some games are completely solved, and in this caseS has a winning strategy iff his set includes a perfect subset, andD has a winning strategy iffS's set is at most denumerable. Some other games, in whichS has to choose only rationals and obey a norm, induce a hierarchy structure on the class of nowhere dense perfect sets, that is embedded cofinally in the lattice of infinite sequences of integers modulo finite differences.  相似文献   
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We investigated the influence of the reduction state of gold ions on the growth of gold nanocrystals in N,N-dimethyl formamide (DMF). While freshly prepared solutions of AuCl3 produce spherical nanocrystals, aged precursor solutions containing mainly Au+ ions and Au(0) atoms lead to various branched nanoparticles. Furthermore, we show that also the amount of the reducing and stabilisation agent tetra-n-octylammonium formate (TOAF) plays a decisive role on the shape of the nanocrystals, allowing us to grow triangular and cubic nanoparticles.  相似文献   
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Plane polyominoes are edge-connected sets of cells on the orthogonal lattice Z2, considered identical if their cell sets are equal up to an integral translation. We introduce a novel injection from the set of polyominoes with n cells to the set of permutations of [n], and classify the families of convex polyominoes and tree-like convex polyominoes as classes of permutations that avoid some sets of forbidden patterns. By analyzing the structure of the respective permutations of the family of tree-like convex polyominoes, we are able to find the generating function of the sequence that enumerates this family, conclude that this sequence satisfies the linear recurrence an=6an−1−14an−2+16an−3−9an−4+2an−5, and compute the closed-form formula an=2n+2−(n3n2+10n+4)/2.  相似文献   
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We present a new metal–organic framework (MOF) built from lanthanum and pyrazine‐2,5‐dicarboxylate (pyzdc) ions. This MOF, [La(pyzdc)1.5(H2O)2] ? 2 H2O, is microporous, with 1D channels that easily accommodate water molecules. Its framework is highly robust to dehydration/hydration cycles. Unusually for a MOF, it also features a high hydrothermal stability. This makes it an ideal candidate for air drying as well as for separating water/alcohol mixtures. The ability of the activated MOF to adsorb water selectively was evaluated by means of thermogravimetric analysis, powder and single‐crystal X‐ray diffraction and adsorption studies, indicating a maximum uptake of 1.2 mmol g?1 MOF. These results are in agreement with the microporous structure, which permits only water molecules to enter the channels (alcohols, including methanol, are simply too large). Transient breakthrough simulations using water/methanol mixtures confirm that such mixtures can be separated cleanly using this new MOF.  相似文献   
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Plasma Chemistry and Plasma Processing - We present an innovative approach for reacting carbon dioxide and water to give syngas by combining heterogeneous catalysis and non-thermal plasma...  相似文献   
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Journal of Solid State Electrochemistry - This study focuses on H2-O2 operando AEMFC performance based on several platinum group metal (PGM) and PGM-free catalysts. Specifically, we evaluate the...  相似文献   
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