Against the flow? What factors dictate the relative merits of microflow reactors versus batch‐reaction flasks for homogeneous catalytic reactions? The optimal reaction protocol must be decided on a case‐by‐case basis. Flask reactors equipped with in situ detection devices provide a concise and information‐rich means of obtaining the intrinsic kinetic information required to make this decision.

Summary Soil is a crucial component of the biosphere and is a major sink for organic carbon. Plant roots are known to release a wide range of carbon‐based compounds into soils, including polysaccharides, but the functions of these are not known in detail.Using a monoclonal antibody to plant cell wall xyloglucan, we show that this polysaccharide is secreted by a wide range of angiosperm roots, and relatively abundantly by grasses. It is also released from the rhizoids of liverworts, the earliest diverging lineage of land plants. Using analysis of water‐stable aggregate size, dry dispersion particle analysis and scanning electron microscopy, we show that xyloglucan is effective in increasing soil particle aggregation, a key factor in the formation and function of healthy soils.To study the possible roles of xyloglucan in the formation of soils, we analysed the xyloglucan contents of mineral soils of known age exposed upon the retreat of glaciers. These glacial forefield soils had significantly higher xyloglucan contents than detected in a UK grassland soil.We propose that xyloglucan released from plant rhizoids/roots is an effective soil particle aggregator and may, in this role, have been important in the initial colonization of land.

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Acid-catalysed dehydration of 3-substituted benzene cis-l,2-di hydrodiols exhibits a Hammett plot with p = -8.2, consistent with reaction via a benzenonium ion-like intermediate; however, correlation of +M resonance substituents such as Me and Me0 by q, rather than (J+ constants indicates a marked imbalance between resonance and inductive stabilisation of the transition state.