There is a considerable interest in the development of photocatalytic CO2 conversion by sunlight since this process has similarities with natural photosynthesis on which life on Earth is based. At the moment, most of the efforts in this field have been aimed at increasing the productivity, rather than at the control of the product distribution. Particularly, compounds with two or more carbons (C2+) have higher added value than methane, carbon monoxide or formate that are typically the major products of CO2 reduction. This review focuses on those reports that have described the formation of compounds of two or more carbon atoms (C2+) in the photocatalytic CO2 reduction either by H2O or as H2 as source of electrons and protons. The existing literature has been organized according to the main factor considered as responsible for the selectivity to C2+ products, including photocatalyst structuration, co-catalyst nature, influence of defects, effects of surface plasmon band. Emphasis has been made on remarking the current 2 empirical knowledge based on experimental results and the lack of predictive capability that could lead to the development of efficient photocatalytic systems for C2+ production.

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Electron capture and loss cross sections for U 28+ colliding with H 2 , N 2 and Ar were measured at 3.5 and 6.5 MeV/u. These data were used to benchmark n-body calculations using the classical trajectory Monte Carlo method. The n-body calculations include electrons on both nuclear centres and all electronelectron and electron-nuclear interactions between each centre. For the U 28+ ion, 36 electrons were incorporated in the calculations (4s 2 4p 6 4d 10 4f 14 5s 2 5p 2 ), while for the H, N and Ar targets all electrons were used except those for the Kshell of Ar, leading to 39-, 45-and 54-body calculations, respectively. Projectile electron loss was predicted for U 28+ at energies from 2 to 150 MeV/u. Only for the H-target did the projectile electron loss cross section decrease approximately as E −1 . The heavier targets exhibited slower energy dependences, contrary to the E −1 prediction of one-electron theories. Moreover, the collisional interactions are quite strong with an average of 1.64 and 2.88 electrons removed from the U 28+ ion at 10 MeV/u in each collision with N and Ar, respectively. These data and calculations were used to assess the vacuum requirements for the SIS-100 synchrotron ring under construction at GSI-Darmstadt. For the residual gases expected to be in the ring, the U 28+ lifetime was found to be essentially constant as a function of projectile energy, leading to very stringent vacuum requirements.

A restriction fragment length polymorphism (RFLP) linkage map of Sorghum bicolor (L.) Moench was constructed in a population of 137 F6‐8 recombinant inbred lines using sorghum, maize, oat, barley and rice DNA clones. The map consists of 10 linkage groups (LGs) and 323 markers, 247 of which (76.5%) were ordered at a LOD score ≥ 3.0. The LGs comprise from 61 (LG A) to 13 markers (J), which range in length from 205 (A) to 55 cM (J) and have a combined total length of 1347 cM. Highly significant distorted segregation was detected at all of the 38 loci in a 103‐cM segment of LG A, the allelic ratios in the segment ranging from approximately 3:1 (one end) to 19:1 (middle) to 2:1 (other end). Duplicated loci located in different LGs have been mapped with 55 of the 295 DNA probes used in the study (18.6%). The distribution of these loci does not provide support for the hypothesis that Sorghum bicolor (L.) Moench is of tetraploid origin. Comparison of the map with RFLP maps of maize, rice, and oat produced evidence for sorghum‐maize LG rearrangements and homoeologies not reported previously, including evidence that: (1) a segment of maize 5L and a segment of 5S may be homoeologous to sorghum LGA; (2) maize LGs 4 and 6 are partly homoeologous to sorghum LGE; (3) the short arm of maize LG 2 is partly homoeologous to sorghum LGF; (4) maize LG 4 may be partly homoeologous to sorghum LG G; (5) maize LG 5 and sorghum LG G contain a larger amount of homoeologous genetic material than previously indicated; and (6) a short segment of maize LG 1 may be homoeologous to a short segment of sorghum LG I.

The review summarizes the state-of-the-art of C–H active transformations over crystalline and amorphous porous materials as new emerging heterogeneous (photo)catalysts.

The use of Metal-Organic Frameworks as crystalline matrices for the synthesis of multiple component or multivariate solids by the combination of different linkers into a single material has emerged as a versatile route to tailor the properties of single component phases or even access new functions. This approach is particularly relevant for Zr6-MOFs due to the synthetic flexibility of this inorganic node. However, the majority of materials is isolated as polycrystalline solids, which are not ideal to decipher the spatial arrangement of parent and exchanged linkers for the formation of homogeneous structures or heterogeneous domains across the solid. Here we use High-Throughput methodologies to optimize the synthesis of single crystals of UiO-68 and UiO-68-TZDC, a photoactive analogue based on a tetrazine dicarboxylic derivative. The analysis of the single linker phases reveals the necessity of combining both linkers to produce multivariate frameworks that combine efficient light sensitization, chemical stability and porosity, all relevant to photocatalysis. We use solvent assisted linker exchange reactions to produce a family of UiO-68-TZDC% binary frameworks, which respect the integrity and morphology of the original crystals. Our results suggest that the concentration of TZDC in solution controls the distribution of this linker in the sibling crystals for a random mixture or the formation of core-shell domains. We also demonstrate how the possibility of generating an asymmetric distribution of both linkers has a negligible effect on the electronic structure and optical bandgap of the solids but controls their performance for drastic changes in the photocatalytic activity towards proton or methyl viologen reduction.

The finding of an extremely large magnetoresistance effect on silicon based p–n junction with vertical geometry over a wide range of temperatures and magnetic fields is reported. A 2500% magnetoresistance ratio of the Si p–n junction is observed at room temperature with a magnetic field of 5 T and the applied bias voltage of only 6 V, while a magnetoresistance ratio of 25 000% is achieved at 100 K. The current‐voltage (I–V) behaviors under various external magnetic fields obey an exponential relationship, and the magnetoresistance effect is significantly enhanced by both contributions of the electric field inhomogeneity and carrier concentrations variation. Theoretical analysis using classical p–n junction transport equation is adapted to describe the I–V curves of the p–n junction at different magnetic fields and reveals that the large magnetoresistance effect origins from a change of space‐charge region in the p–n junction induced by external magnetic field. The results indicate that the conventional p–n junction is proposed to be used as a multifunctional material based on the interplay between electronic and magnetic response, which is significant for future magneto‐electronics in the semiconductor industry.