Poplar plants are cultivated as woody crops, which are often fertilized by addition of ammonium (NH4(+)) and/or nitrate (NO3(-)) to improve yields. However, little is known about net NH4(+)/NO3(-) fluxes and their relation with H(+) fluxes in poplar roots. In this study, net NH4(+)/NO3(-) fluxes in association with H(+) fluxes were measured non-invasively using scanning ion-selective electrode technique in fine roots of Populus popularis. Spatial variability of NH4(+) and NO3(-) fluxes was found along root tips of P. popularis. The maximal net uptake of NH4(+) and NO3(-) occurred, respectively, at 10 and 15 mm from poplar root tips. Net NH4(+) uptake was induced by ca. 48 % with provision of NO3(-) together, but net NO3(-) uptake was inhibited by ca. 39 % with the presence of NH4(+) in poplar roots. Furthermore, inactivation of plasma membrane (PM) H(+)-ATPases by orthovanadate markedly inhibited net NH4(+)/NO3(-) uptake and even led to net NH4(+) release with NO3(-) co-provision. Linear correlations were observed between net NH4(+)/NO3(-) and H(+) fluxes in poplar roots except that no correlation was found between net NH4(+) and H(+) fluxes in roots exposed to NH4Cl and 0 mM vanadate. These results indicate that root tips play a key role in NH4(+)/NO3(-) uptake and that net NH4(+)/NO3(-) fluxes and the interaction of net fluxes of both ions are tightly associated with H(+) fluxes in poplar roots.

Retinal axon pathfinding from the retina into the optic nerve involves the growth promoting axon guidance molecules L1, laminin and netrin 1, each of which governs axon behavior at specific regions along the retinal pathway. In identifying additional molecules regulating this process during embryonic mouse development, we found that transmembrane Semaphorin5A mRNA and protein was specifically expressed in neuroepithelial cells surrounding retinal axons at the optic disc and along the optic nerve. Given that growth cone responses to a specific guidance molecule can be altered by co-exposure to a second guidance cue, we examined whether retinal axon responses to Sema5A were modulated by other guidance signals axons encountered along the retinal pathway. In growth cone collapse, substratum choice and neurite outgrowth assays, Sema5A triggered an invariant inhibitory response in the context of L1, laminin, or netrin 1 signaling, suggesting that Sema5A inhibited retinal axons throughout their course at the optic disc and nerve. Antibodyperturbation studies in living embryo preparations showed that blocking of Sema5A function led to retinal axons straying out of the optic nerve bundle, indicating that Sema5A normally helped ensheath the retinal pathway. Thus, development of some CNS nerves requires inhibitory sheaths to maintain integrity. Furthermore, this function is accomplished using molecules such as Sema5A that exhibit conserved inhibitory responses in the presence of coimpinging signals from multiple families of guidance molecules.

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Sufficient loading of presynthesized quantum dots (QDs) on mesoporous TiO 2 electrodes is the prerequisite for the fabrication of high-performance QD-sensitized solar cells (QDSCs).Here, we provide a general approach for increasing QD loading on mesoporous TiO 2 films by surface engineering. It was found that the zeta potential of presensitized TiO 2 can be effectively adjusted by surfactant treatment, on the basis of which additional QDs are successfully introduced onto photoanodes during secondary deposition. The strategy developed, that is, the secondary deposition incorporating surfactant treatment, makes it possible to load various QDs onto photoanodes regardless of the nature of QDs. In standard AM 1.5G sunlight, a certified efficiency of 10.26% for the QDSC with Cu 2 S/brass counter electrodes was achieved by the secondary deposition of Zn−Cu−In−Se QDs.

Environmentally friendly microencapsulated phase change materials (MEPCMs) with calcium carbonate (CaCO3) shells were modified with graphene oxide (GO), and the effects of GO content and methodology on MEPCMs were examined. The core–shell structure of MEPCMs and crystal structure of CaCO3 shells were confirmed by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffractometer (XRD). The thermal properties and stability of MEPCMs were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), suggesting that the addition of GO contributed to improving the heat storage capacity and thermal stability of MEPCMs. When the GO content was 1.0 wt %, the encapsulation ratio of MEPCMs was as high as 73.19%, and the leakage rate was reduced by 89.6% compared to the MEPCMs without GO. Furthermore, the thermal conductivity and mechanical properties of GO modified MEPCMs were improved significantly. The considerable latent heat storage, thermal stability, thermal conductivity, leakageprevention, and mechanical properties of GO modified paraffin@CaCO3 MEPCMs offer potential in green energy applications.

A series of microencapsulated phase-change materials (MEPCMs) based on paraffin core and calcium carbonate (CaCO 3 ) shell were synthesized, and the effect of emulsifier type and pH value on morphology, structure, and properties of paraffin@CaCO 3 MEPCMs were investigated. The results showed that CaCO 3 shell was formed in vaterite and calcite crystalline phase when emulsifier was sodium dodecyl benzene sulfonate and styrene-maleic anhydride (SMA), respectively. When sodium dodecyl sulfate was used as an emulsifier, both vaterite and calcite CaCO 3 were formed. The forming mechanism of emulsifier type on CaCO 3 crystalline phase was studied. Furthermore, phase-change enthalpy and leakage rate of MEPCMs were related with the type of emulsifier and the pH value of the emulsion. With optimum condition of SMA as emulsifier and pH value of 7, paraffin@CaCO 3 MEPCMs had an encapsulation ratio at 56.6% and leakage rate at 2.88%, illustrating its considerable heat storage capability and leakage-prevention property. The 50 heating−cooling cycles test indicated that the MEPCMs owned excellent thermal reliability. The thermal conductivity of MEPCMs was significantly improved due to the existence of CaCO 3 shell. In addition to excellent thermal storage ability, the paraffin@CaCO 3 MEPCMs also owned good mechanical property and light-to-heat energy conversion efficiency. The characteristics of MEPCMs indicated its potential application in solar energy resource.

RbSbSO4Cl2 exhibits a strong SHG response originating from the synergistic effect of three coexisting constituting asymmetric chromophores.

Two new antimony sulfate chlorides named (NH4)2SbCl­(SO4)2 and (NH4)­SbCl2(SO4) were successfully synthesized through solvent-free synthesis method. (NH4)2SbCl­(SO4)2 exhibits a three-dimensional framework constructed of [SbCl­(SO4)2]2– chains and NH4 + ions. And the NH4 + cations play the role of charge balance and provide the hydrogen bond constructed with oxygen atoms. (NH4)­SbCl2(SO4) shows a two-dimensional layer structure that is composed of the regularly stacked [SbCl2(SO4)]− chains via hydrogen-bonding interactions. Both of the titled compounds possess the same chemical composition and the similar Sb–Cl–SO4 chains, while hydrogen-bonding interactions and lone-pair cations play the synergistic effect on the framework structures and macroscopic centricities resulting in that the (NH4)2SbCl­(SO4)2 is centrosymmetric and the (NH4)­SbCl2(SO4) is non-centrosymmetric (NCS). Powder second harmonic generation (SHG) measurements indicated that the NCS compound (NH4)­SbCl2(SO4) is type I phase-matchable and exhibits SHG responses of ∼1.7 times that of KH2PO4.