Trouble finding the optimal AdS/QCD

In the bottom-up approach to AdS/QCD based on a five-dimensional gravity dilaton action the exponential of the dilaton field is usually identified as the strong or 't Hooft coupling. There is currently no model known which fits the measurements of the running coupling and lattice results for pressure at the same time. With a one parametric toy model we demonstrate the effect of fitting the pressure on the coupling and vice versa.     

S-烷基异硫脲盐作为硫醇替代物经环氧开环反应合成β-羟基硫化物

S-烷基异硫脲盐作为一种无毒、无味、易于制备的硫醇替代物，在碱性水介质中、室温下与多种环氧化合物发生环氧开环反应，区域选择性、高收率地合成了一系列β-羟基硫化物。     

SW-Ⅱ型数显温控XL-Ⅰ箱形高温炉的故障及维修方法

运用电学的基本原理,对数显温控高温炉的故障进行了分析,在实践中总结出各种故障的发生原因、特征现象及解决方法。     

Influence of processing variables on the formation of La2Zr2O7 in transferred arc plasma torch processing

The transferred arc plasma (TAP) torch process has various noteworthy features such as extremely high temperatures, low environmental impact and short processing time which makes it the most suitable technique for synthesizing ceramic composite materials. Furthermore, it is a direct two-step technique which by its virtue of high temperature and power density paves way for high production rate. Hence in this study, an effort has been made to utilize the TAP torch processing technique for the bulk production of La₂Zr₂O₇ with time effectiveness from the mixture of La₂O₃ and ZrO₂ powders (1:2 mol ratios) which were ball milled for 4 h. For this purpose, transferred arc plasma torch was specially designed in laboratory scale level and the operating parameters were optimized in order to achieve maximum La₂Zr₂O₇ formation efficiency. In this study, the phase and microstructure formation of the processed samples was analyzed via X-ray diffraction (XRD) and scanning electron microscope (SEM) images respectively. Moreover, EDX analysis was incorporated to highlight the superior influence of the longer processing time on the stoichiometric ratio of ZrO₂/La₂O₃ in the processed sample as against input power and the gas flow rate.     

Determination of organometallic compounds in surface water and sediment samples with SPME-CGC-ICPMS

Organometal compounds of tin, mercury and lead were simultaneously determined in environmental water and sediment samples by CGC-ICPMS. Instead of classical liquid/liquid extractions, solid phase microextraction was used as sampling technique. In this method, the organometallic compounds arein situ derivatised in the aqueous phase and simultaneously extracted onto a polydimethylsiloxane fiber, so that organic solvents are no longer necessary. The sorbed organometals are subsequently released from the fiber in the GC injection liner by thermal desorption. By sampling from the headspace, only the species of interest are sampled and no interfering matrix components are coextracted. With this new method, derivatisation, extraction, preconcentration and injection into the GC takes only 10 min with a minimum of handling steps. Owing to the very low detection limits (0.13–3.7 ng/1 as metal) only small sample amounts (25 ml of water, 0.5 g of sediment) are needed for one analysis. Finally, SPME is an inexpensive sampling technique that can be used with standard split/splitless injection systems.     

Multi-Channel Optical Device for Solar-Driven Bacterial Inactivation under Real-Time Temperature Feedback

Solar-driven photothermal antibacterial devices have attracted a lot of interest due to the fact that solar energy is one of the cleanest sources of energy in the world. However, conventional materials have a narrow absorbance band, resulting in deficient solar harvesting. In addition, lack of knowledge on temperature change in these devices during the photothermal process has also led to a waste of energy. Here, we presented an elegant multi-channel optical device with a multilayer structure to simultaneously address the above-mentioned issues in solar-driven antibacterial devices. In the photothermal channel, semiconductor IrO₂-nanoaggregates exhibited higher solar absorbance and photothermal conversion efficiency compared with nanoparticles. In the luminescence channel, thermal-sensitive Er-doped upconversion nanoparticles were utilized to reflect the microscale temperature in real-time. The bacteria were successfully inactivated during the photothermal effect under solar irradiation with temperature monitoring. This study could provide valuable insight for the development of smart photothermal devices for solar-driven photothermal bacterial inactivation in the future.     

Densification and lithium ion conductivity of garnet-type Li7-xLa3Zr2-xTaxO12 （x=0.25） solid electrolytes

The garnet-type Li7La3Zr2O12 ceramic is a promising solid electrolyte for all-solid-state secondary lithium batteries. However, it faces the problem of lithium volatilization during sintering, which may cause low density and deterioration of ionic conductivity. In this work, the effects of sintering temperature and addition on the density as well as the lithium ion conductivity of Li7-xLa3Zr2-xTaxO12 (LLZTO, x=0.25) ceramics prepared by solid state reaction have been studied. It is found that optimization of the sintering temperature leads to a minor increase in the ceramic density, yielding an optimum ionic conductivity of 2.9×10-4 S·cm-1 at 25℃. Introduction of Li 3 PO 4 addition in an appropriate concentration can obviously increase the density, leading to an optimum ionic conductivity of 7.2×10-4 S·cm-1 at 25℃. This value is superior to the conductivity data in most recent reports on the LLZTO ceramics.     

Effects of clouds, sea surface temperature, and its diurnal variation on precipitation efficiency

The effects of clouds, sea surface temperature, and its diurnal variation on precipitation efficiency are investigated using grid-scale data from nine equilibrium sensitivity cloud-resolving model experiments driven without large-scale vertical velocity. The precipitation efficiencies are respectively defined in surface rainfall, cloud, and rain microphysical budgets. We mathematically and physically demonstrate the relationship between these precipitation efficiencies. The 2℃ increases in spatiotemporal invariant sea surface temperature (SST) from 27℃ to 29℃ and from 29℃ to 31℃, and the inclusion of diurnal SST difference 1℃ and the 1℃ increase in diurnal SST difference generate opposite changes in the precipitation efficiency by changing ice cloud-radiation interactions. The radiative and microphysical processes of ice clouds have opposite effects on the precipitation efficiency because of the rainfall increase associated with the reduction in the saturation mixing ratio caused by the exclusion of radiative effects and the decrease in rainfall related to the reduction in net condensation caused by the exclusion of deposition processes. The radiative effects of water clouds on the precipitation efficiency are statistically insensitive to the radiative effects of ice clouds.     

Phonon response of the high‐temperature spin‐density‐wave superconductors

The phonon response of a spin density wave superconductor (SD^W-SC) is calculated. The phonon self energy due to electron-phonon interaction, which involves the electronic density response function, is evaluated explicitly for the coexistent SDW-SC state. It has a square-root singularity at a frequency corresponding to the superconducting gap 2Δ. As a consequence, the spectral density function of the SDW-phonon will show a peak at 2Δ The possibility of observing the 2Δ-peak by Raman scattering is discussed. The relevance of the results to high-temperature superconductors is pointed out. The available Raman data for YBa₂Cu₃O_7-δare compared with the results of the calculation.