Phase engineering of Pd–Te nanoplates via potential energy trapping

Phase modulation of noble metal alloys(NMAs)is critically important in nanoscience since the distinct atomic arrangements can largely determine their physicochemical properties.However,the precise modulation of NMAs is formidably challenging,because thermodynamically stable phases are generally preferential compared to those metastable ones.Herein,we proposed a potential energy trapping strategy for phase modulation of Pd–Te alloys with solvents.Thereinto,ethylene glycol can increase the energy barrier for both Pd leaching and Te introduction,forming metastable Pd20Te7 phase.Inversely,N,N-dimethylformamide is unable to trap metastable phase,inducing the phase evolution to thermodynamically stable PdTe phase,and the precise phase modulation was realized including Pd20Te7,PdTe and PdTe2 phases.The Pd–Te alloys displayed phase-dependent formic acid oxidation catalytic performance with PdTe phase showing the best.This work proposes a strategy for creating metastable phase with potential energy trap,which may deepen the understanding of phase engineering for noble metal-based nanocrystals.

Environment, Health and Economic Growth： Study on Optimal Energy Tax Revenue Distribution

Under the dual pressures of economic growth and environmental protection,how to curb pollution and raise public welfare without harming the economy or with minimal economic output losses has become a major question facing China in its efforts to transform growth pattern and accomplish economic transition. On the basis of an overlapping generation(OLG) model, this paper introduces the health effects of environmental pollution to systematically discuss the optimal distribution ratio of energy tax revenues in subsidizing household income and emission abatement under given tax rates to reduce the risks of "environment-health-poverty" trap. Our research shows that an optimal distribution ratio for maximizing per capita output or an optimal distribution ratio for maximizing public welfare exists. Based on China's actual parameters, however, this study has found that China's energy tax revenue distribution policy hardly meets the two optimal targets at the same time. Specific distribution ratio is subject to government decision-making preference, and needs to be adjusted according to actual differences.

ELECTRICALLY FORCED VIBRATION OF A THICKNESS-TWIST MODE PIEZOELECTRIC RESONATOR WITH NON-UNIFORM ELECTRODES

We study the effect of electrodes with varying thickness on thickness-twist vibration of a piezoelectric plate resonator of crystals of 6 mm symmetry. An exact theoretical analysis is performed. Results show that non-uniform electrodes have a strong effect on mode shapes, and suggest the possibility of using nonuniform electrodes for strong energy trapping.

Research on the Necessity of Building National-level Grape and Cherry Germplasm Resources Bank in Shandong Province

At present,the grape and cherry industries in Shandong are in the leading position in China and have driven the development of related high-end manufacturing industries such as wine,brandy,preserved fruit processing,fruit juice processing and health products. Therefore,vigorously developing the grape and cherry industries in Shandong Province and carrying out development and innovation are important parts of Shandong Province in responding to the strategy of national new and old kinetic energy conversion. However,currently the germplasm resources preserved in the fruit tree resources banks in China are only 45% of those in the US and 27. 2% of those in the EU. Moreover,the development of fruit trees resources banks in Shandong is relatively backward in China,and there is still no banks related with grape and cherry germplasm resources in Shandong. Therefore,importance can be attached to the agriculture,forestry,and animal husbandry to build germplasm resources banks for grape and cherry industries in Shandong Province. Building the national-level grape and cherry germplasm resources bank in Shandong Province can also promote the utilization of wild and farm germplasm resources in the future; advance the research on the genes related to disease resistance,stress resistance and quality of grapes and cherries; push forward the construction and development of cherry and grape mutants banks. It is conducive to the research on the agronomic traits of grapes and cherries,and can provide the parents resources for planting innovation and improving the quality of grapes and cherries,as well as promote the development and application of molecular markers of grapes and cherries,including the identification of lines and crossbreeding. Thereby,it cannot only promote the industry development,but also achieve the development of cultivation,breeding and basic research in an all-round way and the development of ＂ production,study and research＂ going side by side.

All-organic nanocomposite dielectrics contained with polymer dots for high-temperature capacitive energy storage

High-temperature polymer dielectrics with high energy density are urgently needed for capacitive energy storage fields.However,the huge conduction loss at elevated temperatures makes the capacitive performance of polymers degrade sharply,limiting the application of them.Herein,the polymer dots(PDs)with high-electron-affinity were introduced into high-temperature polymers to prepare all-organic nanocomposite dielectrics by solution casting.It is found that polymer dots capture injected electrons via strong electrostatic attraction and impede charges transport and accumulation inside composites,thus reducing leakage current density and improving high-temperature energy storage performance.Consequently,the high-temperature capacitance performance of nanocomposites was improved significantly and reached over 2.5 times that of the pristine polymers,e.g.,the energy density of polyetherimide(PEI)/PD reached 3.24 J·cm^(-3)with excellent electrical fatigue reliability over 20,000 times.This work addresses the current problem of poor discharged energy density of polymer dielectrics at high temperatures with a simple and universal method.

Influence of ultra-thin TiN thickness(1.4 nm and 2.4 nm) on positive bias temperature instability(PBTI)of high-k/metal gate nMOSFETs with gate-last process

The positive bias temperature instability（PBTI） degradations of high-k/metal gate（HK/MG） n MOSFETs with thin TiN capping layers（1.4 nm and 2.4 nm） are systemically investigated. In this paper, the trap energy distribution in gate stack during PBTI stress is extracted by using ramped recovery stress, and the temperature dependences of PBTI（90℃,125℃, 160℃） are studied and activation energy（Ea） values（0.13 eV and 0.15 eV） are extracted. Although the equivalent oxide thickness（EOT） values of two TiN thickness values are almost similar（0.85 nm and 0.87 nm）, the 2.4-nm TiN one（thicker Ti N capping layer） shows better PBTI reliability（13.41% at 0.9 V, 90℃, 1000 s）. This is due to the better interfacial layer/high-k（IL/HK） interface, and HK bulk states exhibited through extracting activation energy and trap energy distribution in the high-k layer.

Investigation on the Trap Signature in Organic Semiconductor Turmeric Film Through Current-Voltage Analysis

The analytical description of the trap signature in the charge conduction process of turmeric dye-based organic semiconductor has been presented in this study.An analytical explanation of the built-in potential Ⅴx-Ⅴ graph that emphasizes the presence of trapping states has been provided.Differential analysis of current-voltage(Ⅰ-Ⅴ)characteristics has also been conducted to verify the trap signature of the carrier in the device.The non-monotonous decrement of the G(Ⅴ)-Ⅴ plot verifies the trap signature.The values of trap energy(Et)and trap factor(θ)have been derived from the logarithmic Ⅰ-Ⅴ relationship.From the analysis of the semilogarithmic Ⅰ-Ⅴ plot,the barrier height(ϕbi)of the device has also been determined.The overallⅠ-Ⅴcurve has been taken into account to examine the Richardson-Schottky and Poole-Frenkel effects on the trap-assisted charge conduction process.From the results of the experiment,the Schottky effect has been observed to be effective,which leads to a bulk-limited charge conduction process.

Interaction of Hydrogen and Retained Austenite in Bainite/Martensite Dual-Phase High Strength Steel

The hydrogen trapping phenomena in two bainite/martensite dual-phase high strength steels(U20Si and U20DSi)were investigated by electrochemical permeation technique.The hydrogen diffusivity was calculated from data of permeation delay time,and the diffusion coefficient in U20 Si is far less than that in U20 DSi.Moreover,the hydrogen diffusivity decreases as the volume percent of retained austenite increases.The experiment results show that there are different hydrogen trappings and different volume percents of retained austenite in U20 Si and U20 DSi.The retained austenite is precipitated as films.The trap binding energy for the retained austenite and hydrogen is calculated to be 40.4kJ·mol-1.

Effect of electron traps on long afterglow behavior of Sr_3Al_2O_6:Eu_(0.01)^(2+),Dy_(0.02-x)^(3+),Ho_x^(3+)

The long persistent phosphors Sr3Al2O6：Eu0.012＋,Dy0.02-x3＋,Hox3＋ （x=0, 0.01, 0.02） were prepared by a high temperature solid state reaction. All samples showed a broad band emission peaking at 510 nm, which could be ascribed to Eu2＋ transition between 4f65d1 and 4f7 electron configurations. With the increase of substitution of Ho3＋ ions for the Dy3＋ ions in the as-prepared phosphors Sr3Al2O6：Eu0.012＋,Dy0.02-x3＋,Hox3＋ （x=0, 0.01, 0.02）, the initial intensity of the afterglow obviously decreased. From the thermoluminescence （TL） curves of the samples, we concluded that codoped Ho3＋ ions led to a decline of the trap depth and redistribution of the trap. This may be responsible for the change of afterglow of Sr3Al2O6：Eu0.012＋,Dy0.02-x3＋,Hox3＋ （x=0, 0.01, 0.02）.

Two-Dimensional Coupling Vibration Analysis of Laterally Acoustically Coupled Two-Port Thin-Film Bulk Acoustic Resonators

In this paper,we present an approach to studying the mode coupling vibrations in two-port thin-film bulk acoustic wave resonator(FBAR)devices with two pairs of electrodes deposited on the zinc oxide film.The two-dimensional plate theory established in our previous work is employed,which takes into account the coupling of the operating thickness-extensional mode with the extensional,flexural,fundamental and second-order thickness-shear modes.The propagation of straight-crested waves in the plate is studied,and the state-vector approach is successfully used to simplify the derivation process.For a structurally symmetric device,the modes are separated into quasi symmetric and antisymmetric ones.Frequency spectra and corresponding mode shapes are obtained under the stress-free boundary conditions,respectively,and then coupling effects and energy trapping phenomenon are discussed in detail.Some results for structures with asymmetric electrode distributions are also shown.It is found that the choice of aspect ratio has a great effect on mode couplings of FBAR devices.This study will be useful for the design of FBAR filters and sensors.

Improvement of electrical and photovoltaic properties of methyl red dye based photoelectrochemical cells in presence of single walled carbon nanotubes

In this work, we investigated the effect of single walled carbon nanotubes （SWCNT） on the electrical and photovoltaic properties of methyl red （MR） dye based photoelectrochemical cell （PEC）. MR dye based PEC with LiCl04 as ion salt were fabricated with and without mixing SWCNT. The cells were characterized through electrical and optical measurements. The performance of the devices changed drastically in presence of SWCNT. The transition voltage and trap energy of the cells were estimated from the steady-state dark current voltage （I-V） analysis. The transition voltage and trap energy decreased for MR dye cell in presence of SWCNT. Open circuit voltage （Voc）, short circuit current （Jsc）, fill factor （FF） and power conversion efficiency （v/） increased due to the addition of SWCNT. Further measurement of the transient photo- current showed that the growth and decay of photocurrent was quite faster in presence of SWCNT. The photocurrent decay with time was fitted for both the cells and found to follow a power law relation which indicates dispersive transport mechanism with exponential trap states distrib- uted in between lowest unoccupied molecular orbital （LUMO） and highest occupied molecular orbital （HOMO） levels. Possible interpretation is done on the lowering of trap energy with the photocurrent. These results suggest that SWCNT lowers the trap energy of the cells by providing efficient percolation pathways for the conduction of charges. It is expected that due to lowering of trap energy the residing time of the free carriers within the traps decreases. In other words, it may also be said that the charge recombination decreases. These factors affect the overall conduction of charges and improve the electrical and photovoltaic properties.