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Lianas are predicted to perform better than trees during seasonal drought among tropical forests, which has substantial implications for tree and forest dynamics. Here, we use whole-plant trait comparison to test whether lianas allocated on the resource acquisitive end of the continuum of woody plant strategies. We measured morphological and biomass allocation traits for seedlings of 153 species of trees and lianas occurring in a tropical forest in Thailand during the dry season. We first compared trait differences between lianas and trees directly, and then classified all species based on their trait similarities. We found that liana seedlings had significantly higher specific leaf areas and specific stem lengths than co-occurring tree seedlings. Trait similarity classification resulted in a liana-dominated cluster and a tree-dominated cluster. Compared to the tree-dominated cluster, species in the liana-dominated cluster were characterized by a consistent pattern of lower dry matter content and cheaper and more efficient per dry mass unit investment in both above-and below-ground organs. The consistency of all organs operating in tandem for dry matter content, together with optimized investment in them per mass unit, implied that the lianas and trees can be highly overlapped on the strategy gradient of the resource acquisition continuum.

Transistor-based memories are of particular significance in the pursuit of next-generation nonvolatile memories. The charge storage medium in a transistor-based memory is pivotal to the device performance. In this report, nitrogen doping titania nanocrystals (N-TiO2 NCs) synthesized through a low-temperature nonhydrolytic method are used as the charge storage medium in a graphene transistor-based memory. The decoration of the N-TiO2 NCs enables the device to perform as an ultraviolet (UV) light-programmable nonvolatile optoelectronic memory. Multilevel nonvolatile information recording can be realized through accurate control of the incident light dose, which is ascribed to the vast and firm hole trapping abilities of the N-TiO2 NCs induced by the N dopant. Accordingly, a positive gate voltage can be used to erase the programmed state by promoting the recombination of stored holes in N-TiO2 NCs. This study manifests the importance of trap engineering for information storage and provides an alternative path toward nonvolatile optoelectronic memory. © XXXX American Chemical Society

Transistor-based memories are of particular significance in the pursuit of next-generation nonvolatile memories. The charge storage medium in a transistor-based memory is pivotal to the device performance. In this report, nitrogen doping titania nanocrystals (N-TiO2 NCs) synthesized through a low-temperature nonhydrolytic method are used as the charge storage medium in a graphene transistor-based memory. The decoration of the N-TiO2 NCs enables the device to perform as an ultraviolet (UV) light-programmable nonvolatile optoelectronic memory. Multilevel nonvolatile information recording can be realized through accurate control of the incident light dose, which is ascribed to the vast and firm hole trapping abilities of the N-TiO2 NCs induced by the N dopant. Accordingly, a positive gate voltage can be used to erase the programmed state by promoting the recombination of stored holes in N-TiO2 NCs. This study manifests the importance of trap engineering for information storage and provides an alternative path toward nonvolatile optoelectronic memory. © XXXX American Chemical Society

Transistor-based memories are of particular significance in the pursuit of next-generation nonvolatile memories. The charge storage medium in a transistor-based memory is pivotal to the device performance. In this report, nitrogen doping titania nanocrystals (N-TiO2 NCs) synthesized through a low-temperature nonhydrolytic method are used as the charge storage medium in a graphene transistor-based memory. The decoration of the N-TiO2 NCs enables the device to perform as an ultraviolet (UV) light-programmable nonvolatile optoelectronic memory. Multilevel nonvolatile information recording can be realized through accurate control of the incident light dose, which is ascribed to the vast and firm hole trapping abilities of the N-TiO2 NCs induced by the N dopant. Accordingly, a positive gate voltage can be used to erase the programmed state by promoting the recombination of stored holes in N-TiO2 NCs. This study manifests the importance of trap engineering for information storage and provides an alternative path toward nonvolatile optoelectronic memory. © XXXX American Chemical Society

In this paper, we will experimentally investigate the power threshold (PL-H) in upper single null plasmas with an ITER-like tungsten divertor under different ∇B drift directions on EAST [F. Ding et al., Commissioning and PSI Behavior of the ITER-Like W/Cu Divertor in EAST 22nd PSI, Rome (2016)]. The power threshold for the low (L) to high (H) confinement mode has a clear and positive toroidal magnetic field, BT, dependence when the ∇ B drift points toward the primary X-point (Bx∇B↑). A factor of 2-3 increase in PL-H is observed for the ∇B drift away from the primary X-point (Bx∇B↓). The edge and core impurities quantified by spectroscopy measurements show comparable levels for the transitions for both drift directions. On the other hand, it is found that the divertor Dα emission just prior to the L-H transition is lower for Bx∇B↑, compared with that for Bx∇B↓. The upper in-out divertor asymmetry, as manifested by particle fluxes measured by the divertor triple Langmuir probe, is most marked for Bx∇B↓, and with significantly more particle flux to the outer divertor. The reversing field increases the particle flux into the upper inner and lower outer divertor, reducing the in-out asymmetry. One important distinction between the two field directions has been observed, with respect to the amplitude of the scrape-off layer (SOL) parallel flow. A dedicated experiment under similar target plasma conditions shows a lower SOL density and thus a steeper density gradient slightly inside the separatrix, where a lower PL-H is found for the Bx∇B↑, compared to that for Bx∇B↓. We, therefore, conclude that the fielddependent SOL plasma conditions play an important role in the transition physics.

The electrochemical performance of the aluminum-sulfur (Al-S) battery has very poor reversibility and a low charge/discharge current density owing to slow kinetic processes determined by an inevitable dissociation reaction from Al 2 Cl 7 - to free Al 3+ . Al 2 Cl 6 Br - was used instead of Al 2 Cl 7 - as the dissociation reaction reagent. A 15-fold faster reaction rate of Al 2 Cl 6 Br - dissociation than that of Al 2 Cl 7 - was confirmed by density function theory calculations and the Arrhenius equation. This accelerated dissociation reaction was experimentally verified by the increase of exchange current density during Al electro-deposition. Using Al 2 Cl 6 Br - instead of Al 2 Cl 7 - , a kinetically accelerated Al-S battery has a sulfur utilization of more than 80%, with at least four times the sulfur content and five times the current density than that of previous work.

The electrochemical performance of the aluminum-sulfur (Al-S) battery has very poor reversibility and a low charge/discharge current density owing to slow kinetic processes determined by an inevitable dissociation reaction from Al 2 Cl 7 - to free Al 3+ . Al 2 Cl 6 Br - was used instead of Al 2 Cl 7 - as the dissociation reaction reagent. A 15-fold faster reaction rate of Al 2 Cl 6 Br - dissociation than that of Al 2 Cl 7 - was confirmed by density function theory calculations and the Arrhenius equation. This accelerated dissociation reaction was experimentally verified by the increase of exchange current density during Al electro-deposition. Using Al 2 Cl 6 Br - instead of Al 2 Cl 7 - , a kinetically accelerated Al-S battery has a sulfur utilization of more than 80%, with at least four times the sulfur content and five times the current density than that of previous work.

Haijun Shen,1 Qianqian Gao,1 Qi Ye,1 Shiyun Yang,1 Yuqian Wu,1 Qin Huang,1 Xiaona Wang,2 Zhenhua Sun3 1Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu Province, China; 2Department of Internal Medicine of Jiangsu University Hospital Workers, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, China; 3Department of Thyroid and Breast Surgery, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, China Background and purpose: Nanoparticle-loaded hydrogels – localized drug delivery devices containing a combination of therapeutic nanoparticles and implantable hydrogel – have been recipients of increased focus and interest for cancer treatment. However, it is difficult for the released nanoparticles to penetrate deeply into tumors because of the dense collagen network in the tumor extracellular matrix, which greatly limits their antitumor effect. We hypothesized that the implantation of a hydrogel loaded with both nanoparticles and losartan (Los) might enhance penetration because Los has been proven to effectively reduce collagen levels in various tumors. Herein, we developed a nanoparticle/Los-loaded hydrogel system and evaluated the intratumoral distribution and anticancer effect after peritumoral implantation of nanoparticles. Methods: Fluorescent polystyrene nanoparticles (FPNPs, size ~100 nm) and Los were simultaneously encapsulated in a polyethylene glycol (PEG) hydrogel to form the FPNP/Los-loaded hydrogel. After peritumoral implantation in 4T1 tumor-bearing mice for 2 weeks, intratumoral distributions of FPNPs and collagen level were determined. Based on the results, liposomal doxorubicin (Doxil, ~100 nm) was subsequently substituted for FPNPs in the hydrogel. The cellular uptake and cytotoxicity of the Doxil/Los-loaded hydrogel were studied, and the in vivo antitumor efficacy after peritumoral implantation was evalua

Haijun Shen,1 Qianqian Gao,1 Qi Ye,1 Shiyun Yang,1 Yuqian Wu,1 Qin Huang,1 Xiaona Wang,2 Zhenhua Sun3 1Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu Province, China; 2Department of Internal Medicine of Jiangsu University Hospital Workers, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, China; 3Department of Thyroid and Breast Surgery, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, China Background and purpose: Nanoparticle-loaded hydrogels – localized drug delivery devices containing a combination of therapeutic nanoparticles and implantable hydrogel – have been recipients of increased focus and interest for cancer treatment. However, it is difficult for the released nanoparticles to penetrate deeply into tumors because of the dense collagen network in the tumor extracellular matrix, which greatly limits their antitumor effect. We hypothesized that the implantation of a hydrogel loaded with both nanoparticles and losartan (Los) might enhance penetration because Los has been proven to effectively reduce collagen levels in various tumors. Herein, we developed a nanoparticle/Los-loaded hydrogel system and evaluated the intratumoral distribution and anticancer effect after peritumoral implantation of nanoparticles. Methods: Fluorescent polystyrene nanoparticles (FPNPs, size ~100 nm) and Los were simultaneously encapsulated in a polyethylene glycol (PEG) hydrogel to form the FPNP/Los-loaded hydrogel. After peritumoral implantation in 4T1 tumor-bearing mice for 2 weeks, intratumoral distributions of FPNPs and collagen level were determined. Based on the results, liposomal doxorubicin (Doxil, ~100 nm) was subsequently substituted for FPNPs in the hydrogel. The cellular uptake and cytotoxicity of the Doxil/Los-loaded hydrogel were studied, and the in vivo antitumor efficacy after peritumoral implantation was evalua

The electrochemical performance of the aluminum-sulfur (Al-S) battery has very poor reversibility and a low charge/discharge current density owing to slow kinetic processes determined by an inevitable dissociation reaction from Al 2 Cl 7 - to free Al 3+ . Al 2 Cl 6 Br - was used instead of Al 2 Cl 7 - as the dissociation reaction reagent. A 15-fold faster reaction rate of Al 2 Cl 6 Br - dissociation than that of Al 2 Cl 7 - was confirmed by density function theory calculations and the Arrhenius equation. This accelerated dissociation reaction was experimentally verified by the increase of exchange current density during Al electro-deposition. Using Al 2 Cl 6 Br - instead of Al 2 Cl 7 - , a kinetically accelerated Al-S battery has a sulfur utilization of more than 80%, with at least four times the sulfur content and five times the current density than that of previous work.

The electrochemical performance of the aluminum-sulfur (Al-S) battery has very poor reversibility and a low charge/discharge current density owing to slow kinetic processes determined by an inevitable dissociation reaction from Al 2 Cl 7 - to free Al 3+ . Al 2 Cl 6 Br - was used instead of Al 2 Cl 7 - as the dissociation reaction reagent. A 15-fold faster reaction rate of Al 2 Cl 6 Br - dissociation than that of Al 2 Cl 7 - was confirmed by density function theory calculations and the Arrhenius equation. This accelerated dissociation reaction was experimentally verified by the increase of exchange current density during Al electro-deposition. Using Al 2 Cl 6 Br - instead of Al 2 Cl 7 - , a kinetically accelerated Al-S battery has a sulfur utilization of more than 80%, with at least four times the sulfur content and five times the current density than that of previous work.

Defects play significant roles in properties of graphene and related device performances. Most studies of defects in graphene focus on their influences on electronic or luminescent optical properties, while controlling infrared optoelectronic performance of graphene by defect engineering remains a challenge. In the meantime, pristine graphene has very low infrared photoresponses of similar to 0.01 A/W due to fast photocarrier dynamics. Here we report regulating infrared photoresponses in reduced graphene oxide phototransistors by defect and atomic structure control for the first time. The infrared optoelectronic transport and photocurrent generation are significantly influenced and well controlled by oxygenous defects and structures in reduced graphene oxide. Moreover, remarkable infrared photoresponses are observed in photoconductor devices based on reduced graphene oxide with an external responsivity of similar to 0.7 A/W at least over one order of magnitude higher than that from pristine graphene. External quantum efficiencies of infrared devices reach ultrahigh values of similar to 97%, which to our knowledge is one of the best efficiencies for infrared photoresponses from nonhybrid, pure graphene or graphene-based derivatives. The flexible infrared photoconductor devices demonstrate no photoresponse degradation even after 1000 bending tests. The results open up new routes to control optoelectronic behaviors of graphene for high-performance devices.

Defects play significant roles in properties of graphene and related device performances. Most studies of defects in graphene focus on their influences on electronic or luminescent optical properties, while controlling infrared optoelectronic performance of graphene by defect engineering remains a challenge. In the meantime, pristine graphene has very low infrared photoresponses of similar to 0.01 A/W due to fast photocarrier dynamics. Here we report regulating infrared photoresponses in reduced graphene oxide phototransistors by defect and atomic structure control for the first time. The infrared optoelectronic transport and photocurrent generation are significantly influenced and well controlled by oxygenous defects and structures in reduced graphene oxide. Moreover, remarkable infrared photoresponses are observed in photoconductor devices based on reduced graphene oxide with an external responsivity of similar to 0.7 A/W at least over one order of magnitude higher than that from pristine graphene. External quantum efficiencies of infrared devices reach ultrahigh values of similar to 97%, which to our knowledge is one of the best efficiencies for infrared photoresponses from nonhybrid, pure graphene or graphene-based derivatives. The flexible infrared photoconductor devices demonstrate no photoresponse degradation even after 1000 bending tests. The results open up new routes to control optoelectronic behaviors of graphene for high-performance devices.

Defects play significant roles in properties of graphene and related device performances. Most studies of defects in graphene focus on their influences on electronic or luminescent optical properties, while controlling infrared optoelectronic performance of graphene by defect engineering remains a challenge. In the meantime, pristine graphene has very low infrared photoresponses of similar to 0.01 A/W due to fast photocarrier dynamics. Here we report regulating infrared photoresponses in reduced graphene oxide phototransistors by defect and atomic structure control for the first time. The infrared optoelectronic transport and photocurrent generation are significantly influenced and well controlled by oxygenous defects and structures in reduced graphene oxide. Moreover, remarkable infrared photoresponses are observed in photoconductor devices based on reduced graphene oxide with an external responsivity of similar to 0.7 A/W at least over one order of magnitude higher than that from pristine graphene. External quantum efficiencies of infrared devices reach ultrahigh values of similar to 97%, which to our knowledge is one of the best efficiencies for infrared photoresponses from nonhybrid, pure graphene or graphene-based derivatives. The flexible infrared photoconductor devices demonstrate no photoresponse degradation even after 1000 bending tests. The results open up new routes to control optoelectronic behaviors of graphene for high-performance devices.

TiO(2) nanoparticles with different shapes and surface modifiers can change the hole mobility of a P3HT matrix in TiO(2)/P3HT composite films by three orders of magnitude. The composite films with TiO(2) nanorods modified with pyridine show hole mobilities 2-3 times higher than that of a pristine P3HT film and the mobilities can reach as high as 0.23 cm(2) V(-1)s(-1).

TiO(2) nanoparticles with different shapes and surface modifiers can change the hole mobility of a P3HT matrix in TiO(2)/P3HT composite films by three orders of magnitude. The composite films with TiO(2) nanorods modified with pyridine show hole mobilities 2-3 times higher than that of a pristine P3HT film and the mobilities can reach as high as 0.23 cm(2) V(-1)s(-1).

TiO(2) nanoparticles with different shapes and surface modifiers can change the hole mobility of a P3HT matrix in TiO(2)/P3HT composite films by three orders of magnitude. The composite films with TiO(2) nanorods modified with pyridine show hole mobilities 2-3 times higher than that of a pristine P3HT film and the mobilities can reach as high as 0.23 cm(2) V(-1)s(-1).

The effects of various factors on the resonance coupling between elongated Au nanocrystals and organic dyes have been systematically investigated through the preparation of hybrid nanostructures between Au nanocrystals and the electrostatically adsorbed dye molecules. A nanocrystal sample is chosen for each dye to match the longitudinal plasmon resonance wavelength with the absorption peak wavelength of the dye as close as possible so that the resonance coupling strength can be maximized. The resonance coupling strength is found to approximately increase as the molecular volume-normalized absorptivity is increased. It is mainly determined by the plasmon resonance energy of the Au nanocrystals instead of their shapes and sizes. Moreover, the resonance coupling can be reversibly controlled if the dye in the hybrid nanostructures is pH-sensitive. The coupling can also be weakened in the presence of metal ions. These results will be highly useful for designing resonance coupling-based sensing devices and for plasmon-enhanced spectroscopy.

The effects of various factors on the resonance coupling between elongated Au nanocrystals and organic dyes have been systematically investigated through the preparation of hybrid nanostructures between Au nanocrystals and the electrostatically adsorbed dye molecules. A nanocrystal sample is chosen for each dye to match the longitudinal plasmon resonance wavelength with the absorption peak wavelength of the dye as close as possible so that the resonance coupling strength can be maximized. The resonance coupling strength is found to approximately increase as the molecular volume-normalized absorptivity is increased. It is mainly determined by the plasmon resonance energy of the Au nanocrystals instead of their shapes and sizes. Moreover, the resonance coupling can be reversibly controlled if the dye in the hybrid nanostructures is pH-sensitive. The coupling can also be weakened in the presence of metal ions. These results will be highly useful for designing resonance coupling-based sensing devices and for plasmon-enhanced spectroscopy.

Cores and effect: Water-dispersible core-shell structures and heterostructures incorporating gold nanocrystals of different shapes (polyhedra, cubes, and rods) and a variety of transition metal sulfide semiconductors (ZnS, CdS, NiS, Ag2S, and CuS) are synthesized using cetyltrimethylammonium bromide-encapsulated gold nanocrystals and metal thiobenzoates as starting materials. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

Cores and effect: Water-dispersible core-shell structures and heterostructures incorporating gold nanocrystals of different shapes (polyhedra, cubes, and rods) and a variety of transition metal sulfide semiconductors (ZnS, CdS, NiS, Ag2S, and CuS) are synthesized using cetyltrimethylammonium bromide-encapsulated gold nanocrystals and metal thiobenzoates as starting materials. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

Cores and effect: Water-dispersible core-shell structures and heterostructures incorporating gold nanocrystals of different shapes (polyhedra, cubes, and rods) and a variety of transition metal sulfide semiconductors (ZnS, CdS, NiS, Ag2S, and CuS) are synthesized using cetyltrimethylammonium bromide-encapsulated gold nanocrystals and metal thiobenzoates as starting materials. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

The dynamic behavior of the mixture polymer-1/polymer-2/solvent was studied by quasielastic light scattering. Theoretically, based on random phase approximation, we have proposed a new method that allows one to obtain the self-diffusion coefficients of the homopolymers and the polymer-polymer interaction parameter in the ternary polymer solution from the quasielastic light scattering experiment. The method removes stringent conditions previously imposed on the polymer systems to utilize the theory and is useful for ternary polymer solutions consisting of homopolymers with arbitrary molecular weights and solvent interactions. The method has been used to study different ternary systems, such as PS/PMMA/benzene, where PMMA is isorefractive with benzene, PS-1/PS-2/toluene, where PS-1 and PS-2 are only different in molecular weight, and arbitrary ternary systems PS/PMMA/dioxane and PS/PIP/chloroform. The results obtained from those studies indicate that the self-diffusion coefficients of two polymers depend on total polymer concentration and polymer composition, but the polymerpolymer interaction parameter has a weak concentration and composition dependencies. The effect of an applied electric field(E-field) on the dynamics of polystyrene (PS) in tetrahydrofuran (THF) was also studied by quasielastic light scattering. The concentration of the PS/THF solution was varied from very dilute to semidilute, and the applied E-field was up to 714V/mm. In the dilute regime, the relaxation rate of PS increases sharply with the increase of applied E-field, and the effect magnitude of E-field on the dynamics of PS in THF is nearly constant in the dilute regime. However, in the semidilute regime, the applied E-field has little effect on the dynamics of PS in PS/THF solution. The above results confirm that the electrorheological (ER) effect and the change in free energy due to the applied E-field are not factors in the effect of the E-field on the dynamics of PS in PS/THF. From our stu