Enhancing Hydrogen Generation Through Nanoconfinement of Sensitizers and Catalysts in a Homogeneous Supramolecular Organic Framework.

Enrichment of molecular photosensitizers and catalysts in a confined nanospace is conducive for photocatalytic reactions due to improved photoexcited electron transfer from photosensitizers to catalysts. Herein, the self-assembly of a highly stable 3D supramolecular organic framework from a rigid bipyridine-derived tetrahedral monomer and cucurbit[8]uril in water, and its efficient and simultaneous intake of both [Ru(bpy)3 ]2+ -based photosensitizers and various polyoxometalates, that can take place at very low loading, are reported. The enrichment substantially increases the apparent concentration of both photosensitizer and catalyst in the interior of the framework, which leads to a recyclable, homogeneous, visible light-driven photocatalytic system with 110-fold increase of the turnover number for the hydrogen evolution reaction

THE CYCLIC WHOLENESS OF BING, TAO AND LAW IN SUN TZU’S THE ART OF WAR

The Art of War by Sun Tzu (Pingyin: Sunzi Bing Fa)is well-known as one of the oldest writings in Chinesehistory attributed to an individual author. It is the mostfamous treatise of the Military School (Bingjia), of TheHundred Schools of Thought of the Pre-Qin and Han period.However, the text is often misunderstood in the based uponthe misunderstanding of its terms. Readers and scholarsoften interpret the text in a pragmatic or utilitarian way,ignoring its philosophical Taoist subtexts. In the text, theterm translated as war – Bing – is related to two complicatedphilosophical terms and concepts: Tao (Dao) and Law (Fa).Therefore, for fully understanding Sun Tzu’s philosophicaltreatise on Bing, this paper will investigate, how changesof Tao (Dao) and Law (Fa) in relation to Bing occur in aholistic cycle. Bing, Tao and Law must be coordinated,otherwise any operation whether military or political willnot be in conformity with the Grand Tao, and will not beable to achieve its aims

Design and fabrication of robust broadband extreme ultraviolet multilayers

The random layer thickness variations can induce a great deformation of the experimental reflection of broadband extreme ultraviolet multilayer. In order to reduce this influence of random layer thickness fluctuations, the multiobjective genetic algorithm has been improved and used in the robust design of multilayer with a broad angular bandpass. The robust multilayer with a lower sensitivity to random thickness errors have been obtained and the corresponding multilayer mirrors were fabricated. The experimental results of robust Mo/Si multilayer with a wide angular band were presented and analyzed, and the advantage of robust multilayer design was demonstrated

Electrochemical Synthesis of Rare Earth Ceramic Oxide Coatings

Rare earth ceramic oxides are used in several applications including, phosphors, gas sensors, fuel cells, catalytic converters, and corrosion protection. These materials exhibit attractive properties such as fracture toughness, stiffness, and high strength-to-weight ratios. Synthesis of rare earth oxides includes a long list of techniques, but electrodeposition is one that has not been used as extensively as other techniques. This chapter discusses in detail the electrochemical synthesis of lanthanum, cerium, and praseodymium oxides. The physical and chemical properties of the electrodeposited oxides are characterized by x-ray diffraction, scanning electron microscopy, x-ray photoelectron spectroscopy, and other techniques. The electrochemical synthesis and post-treatment of other rare earth oxides, such as gadolinium, terbium, samarium, neodymium, europium, and dysprosium oxides are also covered in this chapter. Two main mechanisms of electrodeposition for rare earth oxides are discussed in detail

Benzyl (E)-3-(2-bromo-5-meth­oxy­benzyl­idene)dithio­carbazate

The title compound, C16H15BrN2OS2, was obtained from the condensation reaction of benzyl dithio­carbazate and 2-bromo-5-meth­oxy­lbenzaldehyde. In the mol­ecule, the bromo­meth­oxy­phenyl ring and dithio­carbazate fragment are located on the opposite sides of the C=N double bond, showing the E conformation. The dithio­carbazate fragment is approximately planar (r.m.s deviation 0.0187 Å); its mean plane is oriented with respect to the bromo­meth­oxy­phenyl and phenyl rings at 7.60 (12) and 60.08 (9)°, respectively. In the crystal, inversion dimers linked by pairs of N—H⋯S hydrogen bonds occur. A short Br⋯Br contact of 3.5526 (12) Å is observed in the crystal structure

Stacking Group Structure of Fermionic Symmetry-Protected Topological Phases

In the past decade, there has been a systematic investigation of symmetry-protected topological (SPT) phases in interacting fermion systems. Specifically, by utilizing the concept of equivalence classes of finite-depth fermionic symmetric local unitary (FSLU) transformations and the decorating symmetry domain wall picture, a large class of fixed-point wave functions have been constructed for fermionic SPT (FSPT) phases. Remarkably, this construction coincides with the Atiyah-Hirzebruch spectral sequence, enabling a complete classification of FSPT phases. However, unlike bosonic SPT phases, the stacking group structure in fermion systems proves to be much more intricate. The construction of fixed-point wave functions does not explicitly provide this information. In this paper, we employ FSLU transformations to investigate the stacking group structure of FSPT phases. Specifically, we demonstrate how to compute stacking FSPT data from the input FSPT data in each layer, considering both unitary and anti-unitary symmetry, up to 2+1 dimensions. As concrete examples, we explictly compute the stacking group structure for crystalline FSPT phases in all 17 wallpaper groups using the fermionic crystalline equivalence principle. Importantly, our approach can be readily extended to higher dimensions, offering a versatile method for exploring the stacking group structure of FSPT phases

High-temperature high-sensitivity AlN-on-SOI Lamb wave resonant strain sensor

A piezoelectric AlN-on-SOI structured MEMS Lamb wave resonator (LWR) is presented for high-temperature strain measurement. The LWR has a composite membrane of a 1 μm thick AlN film and a 30 μm thick device silicon layer. The excited acoustic waves include Rayleigh wave and Lamb waves. A tensile strain sensor has been prepared with one LWR mounted on a uniaxial tensile plate, and its temperature characteristics from 15.4°C to 250°C and tensile strain behaviors from 0 μϵ to 400 μϵ of Rayleigh wave and S4 mode Lamb wave were tested. The temperature test verifies the adaptability of the tensile strain sensor to temperature up to 250°C, and S4 mode Lamb wave and Rayleigh wave represent almost the same temperature characteristics. The strain test demonstrates that S4 mode Lamb wave shows much higher strain sensitivity (-0.48 ppm/μϵ) than Rayleigh wave (0.05 ppm/μϵ) and confirms its advantage of strain sensitivity. Finally, for this one-LWR strain sensor, a method of beat frequency between S4 mode Lamb wave and Rayleigh wave is proposed for temperature compensation and high-sensitivity strain readout

Spectrophotometric detection of uric acid with enzyme-like reaction mediated 3,3′,5,5′-tetramethylbenzidine oxidation

ABSTRACT. WO3 nanosheets (NSs) were prepared and characterized by X-ray photoelectron spectrometer (XPS), X-ray diffractometer (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The obtained WO3 NSs exhibited peroxidase-like catalytic activity, which can catalyze H2O2 to oxidize       3,3 ',5,5 '-tetramethylbenzidine (TMB) to generate oxidized TMB (oxTMB) with an absorption peak centered at 652 nm. Based on this, a facile method for the spectrophotometric determination of H2O2 was established. Under the selected conditions, the increase in absorbance of oxTMB enabled the detection of H2O2 ranging from 2.0 to 180 μM. Considering the fact that H2O2 is one of the products of urate oxidase (UAO)-catalyzed uric acid (UA) oxidation, a convenient method for the selective determination of UA was further developed with the help of UV–vis spectrophotometer. The increase of absorbance at 652 nm showed a linear response to UA concentration over the range of 2.0–180 μM. The limit of detection for UA was as low as 1.25 μM. More importantly, the proposed method was applied to the determination of UA in serum samples with satisfactory results.   KEY WORDS: Spectrophotometric, WO3 nanosheets, Uric acid, Determination   Bull. Chem. Soc. Ethiop. 2023, 37(1), 11-21.                                                             DOI: https://dx.doi.org/10.4314/bcse.v37i1.2&nbsp