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Cadmium (Cd) contamination is becoming a significant environmental concern due to its persistency in soil. In the subsurface, the fate and transport of Cd are significantly affected by the presence of organic carriers, including bacteria, which are ubiquitous. In this research, facilitated Cd transport by four different bacterial strains in zeolite was investigated by column experiments under three different Cd introduction scenarios (i.e., a Cd and bacteria mixture, Cd and bacteria introduced separately but simultaneously, and Cd added to the column, followed by bacterial flushing), through which Cd–bacteria complexes formed. In turn, Cd–bacteria complexation affected bacterial transport. Bacteria were least retarded when Cd was pre‐deposited, with mass recovery>90% for all strains. More Cd was recovered when introduced as a mixture with bacteria (i.e., Cd mass recovery ranging from 16 to 25%). Obtained bacteria and Cd breakthrough curves were simulated by the attachment–detachment model in Hydrus‐1D. Damkohler number and reversibility were both found to be suitable to control the mass recovery of Cd and bacteria in all investigated scenarios. Core Ideas: The introduction scenario significantly affected the transport of Cd and bacteria.Cd was most recovered when Cd–bacteria complexation was fully developed.Attachment, detachment, and convection competition determines Cd breakthrough. [ABSTRACT FROM AUTHOR]

Two new donor (D)-acceptor (A) copolymers, poly({4,4′-[4,4′-(9 H-fluorene-9,9-diyl)bis(4,1-phenylene)]bis(oxy)diphthalonitrile}- alt-[dithieno [3,2- b:2′,3′- d]pyrrole]) (P1) and poly({4,4′-[4,4′-(9 H-fluorene-9,9-diyl)bis(4,1-phenylene)]bis(oxy)diphthalonitrile}- alt-([1,2- b:4,5-b′]dithiophene)) (P2), have been designed and synthesized by the Stille coupling reaction. The dipole moment of P1 (10.71 Debye) is larger than that of P2 (6.59 Debye). A strong dipole moment helps to sustain the conductive charge-transfer state. To evaluate the nonvolatile memristive performance of P1 and P2, the corresponding memory device can be fabricated with the configuration of platinum (50 nm)/polymer (100 nm)/platinum (150 nm)/silicon. In contrast with the P2-based device with almost negligible switching and memristive behavior, the P1-based memristor exhibits a maximum ILRS/ IHRS ratio of about 10 ( ILRS and IHRS are the current values in the low-resistance state (LRS) and high-resistance state (HRS), respectively) at ±2.0 V. Distinguishable from the bistable resistive switching, showing abrupt resistance or conductance jumps, the electrical transition observed in the memristor demonstrates a smoother tuning of the sample conductance during the voltage sweeping processes. In addition, changes in the surface morphology of P1 and P2 are also observed under an applied bias voltage of 100 mV. [ABSTRACT FROM AUTHOR]

The cover picture shows fundamental passive circuit elements of resistor, capacitor, inductor and memristor, and the correlations between the circuit variables. Memristor has been considered capable of mimicking the function of a mammalian synapse with the ability to learn and memorize new information, and to allow powerful and energy‐efficient processing capability for complex open‐ended computing tasks. Details are given in the Full Paper on page 1263 ff. by Y. Chen and co‐workers. [ABSTRACT FROM AUTHOR]