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Adamantane substituted with two to four 4-cyanophenyl groups was used for preparation of a new series of robust Porous Covalent Triazine-based Framework (PCTF) materials. Novel adamantane PCTFs were synthesized in good yields (>80%) by the trimerization reaction of 1,3-bis-, 1,3,5-tris-and 1,3,5,7tetrakis(4-cyanophenyl)adamantane, respectively, in the presence of ZnCl 2 (Lewis acid condition) and CF 3 SO 3 H (strong Brønsted acid condition). From N 2 adsorption isotherms, the Lewis acid condition gives higher surface areas than the strong Brønsted acid condition. The amorphous nano-to microporous frameworks (>50% micropore fraction) exhibit excellent thermal stabilities (>450 C) with BET surface areas up to 1180 m 2 g À1 . A very similar ultramicropore size distribution between 4 and 10 Å was derived from CO 2 adsorption isotherms with a "CO 2 on carbon based slit-pore model". At 1 bar the gases H 2 (at 77 K), CO 2 (at 273 and 293 K) and CH 4 (at 273 K) are adsorbed up to 1.24 wt%, 58 cm 3 g À1 and 20 cm 3 g À1 , respectively. Gas uptake increases with BET surface area and micropore volume which in turn increase with the number of cyano groups in the monomer. From single component adsorption isotherms, IAST-derived ideal CO 2 :N 2 , CO 2 :CH 4 and CH 4 :N 2 selectivity values of up to 41 : 1, 7 : 1 and 6 : 1, respectively, are calculated for p / 0 at 273 K. The adamantane PCTFs have isosteric heats of adsorption for CO 2 of 25-28 kJ mol À1 at zero loading and most of them also >25 kJ mol À1 over the entire adsorption range which is well above the heat of liquefaction of bulk CO 2 or the isosteric enthalpy of adsorption for CO 2 on activated carbons.

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Biochar applications to soils can improve soil fertility by increasing the soil's cation exchange capacity (CEC) and nutrient retention. Because biochar amendment may occur with the applications of organic fertilizers, we tested to which extent composting with farmyard manure increases CEC and nutrient content of charcoal and gasification coke. Both types of biochar absorbed leachate generated during the composting process. As a result, the moisture content of gasification coke increased from 0.02 to 0.94 g g, and that of charcoal increased from 0.03 to 0.52 g g. With the leachate, the chars absorbed organic matter and nutrients, increasing contents of water-extractable organic carbon (gasification coke: from 0.09 to 7.00 g kg; charcoal: from 0.03 to 3.52 g kg), total soluble nitrogen (gasification coke: from not detected to 705.5 mg kg; charcoal: from 3.2 to 377.2 mg kg), plant-available phosphorus (gasification coke: from 351 to 635 mg kg; charcoal: from 44 to 190 mg kg), and plant-available potassium (gasification coke: from 6.0 to 15.3 g kg; charcoal: from 0.6 to 8.5 g kg). The potential CEC increased from 22.4 to 88.6 mmol kg for the gasification coke and from 20.8 to 39.0 mmol kg for the charcoal. There were little if any changes in the contents and patterns of benzene polycarboxylic acids of the biochars, suggesting that degradation of black carbon during the composting process was negligible. The surface area of the biochars declined during the composting process due to the clogging of micropores by sorbed compost-derived materials. Interactions with composting substrate thus enhance the nutrient loads but alter the surface properties of biochars.

Summary To provide valuable support for successful decision‐making, managers need a balanced set of financial and nonfinancial measures that represent different requirements, strategic goals, strategies, resources, and capabilities and the causal relationships between these domains. The balanced scorecard is such a measurement system. As an open system the balanced scorecard facilitates the consideration of sustainability issues. But enhanced balanced scorecards require a new type of data. This is where eco‐efficiency analysis comes into play. This article discusses the relationship between so‐called sustainability balanced scorecards and eco‐efficiency analysis. Eco‐efficiency analysis not only provides a data source for sustainability balanced scorecards; in the perspective of environmental information systems it also serves as a link between the balanced scorecard and corporate environmental accounting systems so that eco‐efficiency as a component of an environmental information system becomes an adapter with two interfaces, which are characterized in this article. The main focus is on the principle of cause and effect, its different forms, and the implications for the design of appropriate information system components.

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