A safe minimum standard,the elasticity of substitution,and the cleanup of the Ganges in Varanasi

Despite repeated calls for a thorough cleanup of water pollution in the Ganges river, there are only two papers in the social sciences by Batabyal and Beladi (2017, 2019) that have shed theoretical light on this cleanup problem and its connection to the sustainability of tourism in Varanasi. Hence, we extend the above‐mentioned analyses and focus on two specific questions. First, we introduce the notion of a safe minimum standard (SMS) into the study and show how to analyze a probabilistic model of the Ganges cleanup problem when the SMS is accounted for. Second, for a representative citizen of Varanasi, we study how the magnitude of the elasticity of substitution between a composite consumption good and water quality in the Ganges—modeled by the SMS—affects the tradeoff between consumption and water quality maintenance.     

Two novel d10 transition metal complexes based on 1H‐benzimidazole‐5,6‐dicarboxylic acid: Synthesis,structure and multifunctional luminescence detection

Two new coordination complexes based on benzimidazole dicarboxylic acid, Zn(Hbidc)?H₂O ( 1 ) and Cd(Hbidc)(H₂O) ( 2 ), have been synthesized under hydrothermal conditions. The complexes were characterized using elemental analysis, infrared and UV–visible spectroscopies, powder X‐ray diffraction, thermogravimetry and single‐crystal X‐ray diffraction. Structural analyses showed that the crystal structures of 1 and 2 are different, due to the various modes of linking of the benzimidazole dicarboxylic acid. Complex 1 has a two‐dimensional network structure and 2 has a three‐dimensional network structure. In addition, we studied the performance of the fluorescence response of two complexes. Results showed that the complexes can be used as chemical sensors for multifunctional testing, such as for UO₂²⁺, xanthine and Fe³⁺ ions. Even if the concentration is very low, they could also be detected, showing that coordination complexes 1 and 2 have very high fluorescence sensitivity. The detection limit for UO₂²⁺ is 5.42 nM ( 1 ) and 0.02 nM ( 2 ), that for xanthine is 1.37 nM ( 1 ) and 0.28 nM ( 2 ), and that for Fe³⁺ ions is 0.76 nM ( 1 ) and 0.62 nM ( 2 ).     

Panisuffrutin A,a highly degraded seco-triterpene derivative from Paeonia suffruticosa var. papaveracea (Andr.) Kerner

Panisuffrutin A (1), a highly degraded seco-triterpene derivative, together with the known palbinone, has been isolated from the whole plant Paeonia suffruticosa var. papaveracea (Andr.) Kerner. The structure with absolute configuration of 1 was determined via comprehensive NMR and MS analyses, as well as NMR and ECD calculations. A plausible biosynthetic pathway for 1 was proposed. Compound 1 showed weak cytotoxicity against Hela cancer cell line with an IC₅₀ value of 26.2 μM, while palbinone exhibited a moderate inhibition on NO production with an IC₅₀ of 18.3 μM.     

Development and application of electrochemical sensor of boron-doped diamond (BDD) modified by drop casting with tin hexacyanoferrate

Journal of Solid State Electrochemistry - This work presents the development and characterization of an electrochemical sensor of tin hexacyanoferrate (SnHCF), produced from the modification by...     

强耦合腔-QED系统中原子的纳秒脉冲激发光谱研究

本文在多原子强耦合腔-QED系统中,利用脉冲宽度为5 ns的强脉冲光在垂直于腔轴方向直接激发原子,脉冲的峰值功率为40 mW,通过光学腔观测激发原子辐射到腔中的光子获得相应的激发光谱。我们发现当光场频率和原子跃迁失谐±80 MHz时原子激发率达到最大,而在共振时原子激发被抑制。我们建立了脉冲光与三能级原子相互作用的模型,通过缀饰态能够解释此现象。     

Output feedback regulation of time-delay nonlinear systems with unknown continuous output function and unknown growth rate

Nonlinear Dynamics - This paper is concerned with the global regulation via output feedback for the time-delay nonlinear systems with unknown continuous output function and unknown growth rate....     

Three-dimensional interfacial fracture analysis of a one-dimensional hexagonal quasicrystal coating

In this paper, the three-dimensional (3D) interfacial fracture is analyzed in a one-dimensional (1D) hexagonal quasicrystal (QC) coating structure under mechanical loading. A planar interface crack with arbitrary shape is studied by a displacement discontinuity method. Fundamental solutions of interfacial concentrated displacement discontinuities are obtained by the Hankel transform technique, and the corresponding boundary integral-differential equations are constructed with the superposition principle. Green’s functions of constant interfacial displacement discontinuities within a rectangular element are derived, and a boundary element method is proposed for numerical simulation. The singularity of stresses near the crack front is investigated, and the stress intensity factors (SIFs) as well as energy release rates (ERRs) are determined. Finally, relevant influencing factors on the fracture behavior are discussed.     

Promoting the Phosphidation Process using an Oxygen Vacancy Precursor for Efficient Hydrogen Evolution Reaction

Based on previous works, most of the transition metal phosphides (TMPs) were directly prepared by decomposing NaH₂PO₂ with the precursors at high temperatures, which resulted in different degrees of phosphidation in the final product. Therefore, it is necessary to design an innovative approach to enhance the degree of phosphidation in the material using crystal defects. Here, oxygen-vacancy iron oxide/iron foam (Ov-Fe₂O₃/IF) was firstly prepared by generating oxygen vacancy in situ in an iron foam through heating in vacuum conditions. Subsequently, FeP/IF was formed by phosphating Ov-Fe₂O₃/IF. Under the effects of oxygen vacancies, oxygen-vacancy iron oxide could be completely phosphatized to produce more active sites on the surface of the material. This, in turn, could result in a catalyst with exceptional hydrogen evolution activity. Thus, the successful fabrication of FeP/IF demonstrated in this work provides an effective and feasible way for the preparation of other high-efficiency catalysts.     

Characterization of Different Salt Forms of Chitooligosaccharides and Their Effects on Nitric Oxide Secretion by Macrophages

In this paper, chitooligosaccharides in different salt forms, such as chitooligosaccharide lactate, citrate, adipate, etc., were prepared by the microwave method. They were characterized by SEM, FTIR, NMR, etc., and the nitric oxide (NO) expression was determined in RAW 264.7 cells. The results showed that pure chitooligosaccharide was an irregular spherical shape with rough surface, and its different salt type products are amorphous solid with different honeycomb sizes. In addition to the characteristic absorption peaks of chitooligosaccharides, in FTIR, the characteristic absorption of carboxyl group, methylene group, and aromatic group in corresponding acid appeared. The characteristic absorption peaks of carbon in carboxyl group, hydrogen and carbon in methyl, methylene group, and aromatic group in corresponding acid also appeared in NMR. Therefore, the sugar ring structure and linking mode of chitooligosaccharides did not change after salt formation of chitooligosaccharides. Different salt chitooligosaccharides are completely different in promoting NO secretion by macrophages, and pure chitooligosaccharides are the best.     

How do molecular interactions affect fluorescence behavior of AIEgens in solution and aggregate states?

Molecular interactions are crucial in diverse fields of protein folding,material science,nanotechnology,and life origins.Although mounting experimental research controls luminescent behavior by adjusting molecular interactions in light-emitting materials,it remains elusive to correlate microscopic molecular interactions with macroscopic luminescent behavior directly.Here,we synthesized three red luminogens with subtle structural variation and investigated the influence of molecular interactions on their luminescent behavior in solution and aggregate states.Our results indicate that strongπ-πand D-A interactions in both dilute solution(between luminogen and solvent molecules)and aggregate(between luminogens)states cause the redshift in emission,while weak interactions(e.g.,Van der Waals,C–H…π,and C–H…F interactions)enhance the quantum yield.This work provides a thoughtful investigation into the complicated influence of various molecular interactions on luminescent behavior.