A 1-mm-diameter all-light atom guide capable of transporting ultracold atoms tens of centimeters with high efficiency is described. We made the atom tunnel, a dark hollow beam that is blue detuned from resonance, by passing a few tens of milliwatts of power from a TEM 00 diode laser beam through an optical sequence composed of three axicons and a simple lens. We demonstrate transport of 10 8 Cs atoms approximately 20 cm with minimal heating. We show that it is possible for one to control the direction and speed of the atoms in the tunnel by varying the detuning of the tunnel beam.

Dual-mesoporous ZSM-5 zeolite with highly b axis oriented large mesopores was synthesized by using nonionic copolymer F127 and cationic surfactant CTAB as co-templates. The product contains two types of mesopores--smaller wormlike ones of 3.3 nm in size and highly oriented larger ones of 30-50 nm in diameter along the b axis--and both of them interpenetrate throughout the zeolite crystals and interconnect with zeolite microporosity. The dual-mesoporous zeolite exhibits excellent catalytic performance in the condensation of benzaldehyde with ethanol and greater than 99 % selectivity for benzoin ethyl ether at room temperature, which can be ascribed to the zeolite lattice structure offering catalytically active sites and the hierarchical and oriented mesoporous structure providing fast access of reactants to these sites in the catalytic reaction. The excellent recyclability and high catalytic stability of the catalyst suggest prospective applications of such unique mesoporous zeolites in the chemical industry.

Mesoporous TS-1 zeolites (MTS-1) were prepared through direct hydrothermal treatment by using CTAB as the mesoporogen under the assistance of ethanol, and they demonstrated much higher catalytic activity and better recyclability in thiophene oxidation, due to the decreased hydrophobicity and mesoporous structure.New regulations for ultra clean oils with a sulfur content lower than 15 or 10 ppm have been mandated in United States and European countries for environmental protection, respectively. Similarly this year, China has implemented the Euro 5 (10 ppm) standard in some big cities like Beijing. Thus, the production of ultra clean oils is an urgent mission for oil industries. However, the cost to reduce the sulfur content from 500 ppm to 15 ppm is much higher than that needed in desulfurizing crude oils to 500 ppm, by using present technologies like hydrodesulfurization (HDS) process. 1,2 The presence of ''inactive sulfur'' like thiophene and its derivates (benzothiophenes and dibenzothiophenes) are refractory and always need treating in fuels under high pressure of hydrogen at elevated temperatures in the HDS process. 2,3 Hence, oxidative desulfurization (ODS), biodesulfurization, ultrasoundassisted technique and solvent extraction have been proposed to meet the stringent regulations. 1,3-5 Among them, oxidative desulfurization which has been developed for about 10 years, combined with solvent extraction, are one of the most promising techniques to obtain ultra-clean oils or even ''zero-sulfur'' oils, and have gained great interest in the past few years. 1,3,6 Benzothiophene (BT), dibenzothiophene (DBT) and their corresponding alkyl-substitutes with high electron density of sulfur atoms, could be oxidized into corresponding sulfones through various reaction systems, such as organic peracids, 7,8 H 2 O 2 / tungsten salts, 9 t-butylhydroperoxide/transition metaloxides, 10 H 2 O 2 /solid redox catalysts, 11-13 and H 2 O 2 /tungsten/ionic liquids complexes. 14,15 However, thiophene, another major source of sulfur compounds in oils, is highly stable and difficult to be oxidized due to the delocalization effect of its electrons. 4,16 The electron density of the sulfur atom in thiophene is as low as 5.696, which cannot meet the lowest standard between 5.716 and 5.739 for sulfoxidation by using hydrogen peroxide as oxidants. 8 Thus, the oxidation of thiophene is much more difficult than either BT or DBT, or their derivates. A large number of literatures have demonstrated that Ti-containing molecular sieves (Ti-Beta and Ti-HMS) combined with H 2 O 2 are active and environmental friendly in the oxidation of BTs and DBTs. 11,[17][18][19] Among them, titanium silicalite-1 (TS-1) zeolites, because of its superior hydrophobicity and intrinsically higher catalytic activity than Ti-Beta, is on the top of a few highly active catalysts in thiophene oxidation. [20][21][22][23][24][25] With the incorporation of Ti into a MFI framework, TS-1 zeolites are crystalline with an extensive microporosity of about 0.55 nm in pore diameter...

The relationship between mechanical stress states and interfacial electrochemical thermodynamics of Li metal/Li6.5La3Zr1.5Ta0.5O12 and Na metal/Na‐β”‐Al2O3 systems are examined in two experimental configurations with an applied uniaxial load; the solid electrolytes are pellets and the metal electrodes high‐aspect‐ratio electrodes. The experimental results demonstrate that 1) the change in equilibrium potential at the metal/electrolyte interface, when stress is applied to the metal electrode, is linearly proportional to the molar volume of the metal electrode, and 2) the mechanical stress in the electrolyte has a negligible effect on the equilibrium potential for an experimental setup in which the electrolyte is stressed and the electrode is left unstressed. Solid mechanics modeling of a metal electrode on a solid electrolyte pellet indicates that pressure and normal stress are within ≈0.5 MPa of each other for the high aspect ratio (≈1:100 thickness:diameter in our study) Li metal electrodes under loads that exceed yield conditions. This work should aid in advancing the quantitative understanding of alkali metal dendrite formation within incipient cracks and their subsequent growth, and pore formation upon stripping, both situations where properly accounting for the impact of mechanical state on the equilibrium potential is of critical importance for calculating the current distribution.

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The hierarchically porous and iron-functionalized zeolite ZSM-5 has been fabricated as a Fenton photocatalyst by a facile post-treatment process, which exhibits an excellent visible-light catalytic property in the adsorption/degradation of organic pollutants under mild reaction conditions.

To address the limitation of the existing UAV (unmanned aerial vehicles) photoelectric localization method used for moving objects, this paper proposes an improved two-UAV intersection localization system based on airborne optoelectronic platforms by using the crossed-angle localization method of photoelectric theodolites for reference. This paper introduces the makeup and operating principle of intersection localization system, creates auxiliary coordinate systems, transforms the LOS (line of sight, from the UAV to the target) vectors into homogeneous coordinates, and establishes a two-UAV intersection localization model. In this paper, the influence of the positional relationship between UAVs and the target on localization accuracy has been studied in detail to obtain an ideal measuring position and the optimal localization position where the optimal intersection angle is 72.6318°. The result shows that, given the optimal position, the localization root mean square error (RMS) will be 25.0235 m when the target is 5 km away from UAV baselines. Finally, the influence of modified adaptive Kalman filtering on localization results is analyzed, and an appropriate filtering model is established to reduce the localization RMS error to 15.7983 m. Finally, An outfield experiment was carried out and obtained the optimal results: σB=1.63×10−4 false(°false), σL=1.35×10−4 false(°false), σH=15.8 false(mfalse), σsum=27.6 false(mfalse), where σB represents the longitude error, σL represents the latitude error, σH represents the altitude error, and σsum represents the error radius.

Multi-exposure image fusion (MEF) is emerging as a research hotspot in the fields of image processing and computer vision, which can integrate images with multiple exposure levels into a full exposure image of high quality. It is an economical and effective way to improve the dynamic range of the imaging system and has broad application prospects. In recent years, with the further development of image representation theories such as multi-scale analysis and deep learning, significant progress has been achieved in this field. This paper comprehensively investigates the current research status of MEF methods. The relevant theories and key technologies for constructing MEF models are analyzed and categorized. The representative MEF methods in each category are introduced and summarized. Then, based on the multi-exposure image sequences in static and dynamic scenes, we present a comparative study for 18 representative MEF approaches using nine commonly used objective fusion metrics. Finally, the key issues of current MEF research are discussed, and a development trend for future research is put forward.