Polymer complexes. LXXVIII. Synthesis and characterization of supramolecular uranyl polymer complexes: Determination of the bond lengths of uranyl ion in polymer complexes

The UO₂(II) polymer complexes (1–5) of azo dye ligands 5(4`‐derivatives phenylazo)‐8‐hydroxy‐7‐quinolinecarboxaldehyde (HL_x) were prepared and characterized by elemental analysis, ¹H NMR, IR spectra, thermal analysis and X‐ray diffraction analysis (XRD). The molecular geometrical structures and quantum chemical of the ligands (HL_x) and their tautomeric forms (D and G) were calculated. Molecular docking between the HL_x ligands and their tautomeric form with two receptors of the breast cancer (1JNX) and the prostate cancer (2Q7K) was discussed. From the histogram of the HOMO–LUMO energy gap (ΔE) and the estimated free energy of binding of the receptors of prostate cancer (2Q7K) and breast cancer (1JNX) for the ligands (HL_x), it is observed that the ΔE values of the ligands (HL_x) increases in the order HL₂ < HL₃ < HL₄ < HL₁ < HL₅. The electronic structures and coordination were determined from a framework for the modeling of the formed polymer complexes. From the IR spectra of the polymer complexes, the symmetric stretching frequency υ₃ values of UO₂²⁺ were used for the determination of the force constant (F_U‐O (in 10^?8 N/?)) and the bond length (R_U‐O (?)) of the U–O bond by using Wilson, G. F. matrix method, McGlynn & Badger's formula and El‐Sonbati equations. The plot of the bond distance r_U‐O (r₁, r₂, r₃, and r_t) vs. υ₃ was showed straight lines with increase in the value of υ₃ and decrease in r_U‐O.     

Mechanical properties,lattice thermal conductivity,infrared and Raman spectrum of the fullerite C24

Lightweight carbon materials with excellent thermal and mechanical properties have important applications in aerospace industry. In this study, the stability, mechanical properties, lattice thermal conductivity, electronic structure, infrared and Raman spectrum of sp³ hybridized low-density fullerite C₂₄ were investigated according to density functional theory (DFT) calculations. It was found that the fullerite C₂₄ was both thermodynamic and dynamic stable. Quasi-harmonic approximation and Grüneisen parameter calculations clarified why the fullerite C₂₄ had a positive thermal expansion coefficient at low temperature. The fullerite C₂₄ also exhibited excellent mechanical properties. Interestingly, the Vickers hardness of carbon allotropes was found to almost be linear proportional to the density of a carbon material. HSE06 electronic structure calculations showed that it was a semiconductor with direct bandgap of 2.56 eV. Anharmonic lattice dynamic calculations showed that its thermal conductivity was higher than semiconductor silicon. Besides, Raman and infrared active modes as well as the corresponding spectra were presented.     

Effectiveness of dairy treated wastewater and different irrigation systems on the growth,biomass and fruiting of a Tunisian olive orchard (Olea europaea L., cv Chemlali)

Abstract

The effectiveness of dairy treated wastewater (TWW) was evaluated, in comparison with tap water (TW), on a Tunisian olive orchard (Olea europea, cv Chemlali), irrigated manually (MI) and by surface dripping (SDI). To this purpose, tree growth, biomass and fruiting were monthly tested for a one-year period. Similar trunk diameters, nodes/tree, root lengths were obtained, independently of source and system of irrigation. Also, comparable tree length and leaf area, shoots/tree and biomass, were observed between TWW and TW plants. However, such parameters improved under SDI rather than MI. Fruiting occurred only in TWW and TW trees treated by MI. Concerning growth, biomass and fruiting, TWW represented a valid alternative source for the irrigation of olive orchard, especially in Tunisia, already facing the freshwater scarcity. Monitoring of soil, TWW, fruits and oil will be required to validate the use of such effluent for olive orchard irrigation.     

中压气源的亚/跨音速射流噪声试验台设计*

在全消声室配套射流噪声试验台是开展射流噪声机理和测量方法研究的重要基础。该文研究了中压气源亚/跨音速射流噪声试验台设计,包括设计指标分析、系统软硬件组成、调试以及达到的效果等。结果表明,采用两级调压的方式可以较好地满足射流噪声研究所需的流量和压力需求,同时通过合理的流道设计,控制精度和流场品质均达到较高要求。与国际主流结果对比表明,该试验台测得的射流噪声信号具有极低的干扰噪声水平。     

Excited state proton transfer based two color fluorescence: Perspectives and some biophysical applications

Photoinduced excited state intramolecular proton transfer (ESIPT) reactions comprise an important and extensively explored class of reactions in photochemistry. Till date, plant flavonols are one of the most widely known class of naturally abundant organic molecules exemplifying ESIPT and ‘two color’ fluorescence. From a bio-medical perspective, flavonols and related polyphenols, which are powerful antioxidants, have attracted significant interest as novel drugs (of high potency and low cyto-toxicity) for the prophylaxis and therapy of free radical induced and other important diseases. This article presents perspectives on proton transfer in photoexcited organic molecules from a historical context, emphasizing ESIPT reactions, in particular. Highlights of representative research findings are discussed, exemplifying the promising potential of plant flavonols as their own ESIPT based ‘fluorescence sensors’ for exploring their interactions with proteins, DNA (possessing duplex as well as higher order structures), and biomembranes, which represent the targets underlying the various pharmacological actions of flavonols. The usefulness of such approach for studying the confinement of intrinsically fluorescent flavonols in nano-vehicles for drug encapsulation, is also demonstrated.     

AUTOMATIC IDENTIFICATION OF MESOSCOPIC PARAMETERS OF DISCRETE ELEMENTS OF SAND MATERIAL 1)

本文依照四川大学某理论力学教学班实际教学改革的经验,通过具体举例说明计算机技术在理论力学教学中尚未开发的巨大潜力,减小数学运算使学生重点关注理论力学基本原理,批量求解使学生提前接触实际应用案例,普适性求解使学生深化对处理多变量问题的认识。同时本文还探讨了理论力学教学改革的方向和目的,即把教学重点放在普适的教学方法上,借助计算机求解多刚体、多变量问题,以期有助于理论力学教材更好地适应时代发展。     

CSP—1方案的中止概率曲线及其应用

本文结合国家标准ＧＢ８０５２—８７［１］，利用中止概率曲线的概念，讨论了连续抽样方案ＣＳＰ—１的中止检查规则及其统计特性，并提出了确定最优中止参数的原则和方法     

利用改进的Glauber模型对非奇异核核反应总截面数据的拟合

在对反应总截面的理论计算中,现有的理论计算值与实验数据在高能区可以很好的符合，但在中能区理论值低于实验值约10％—20％.通过对计算核反应总截面的Glauber模型加入有限程修正，并对输入的核物质密度分布采用双参数的费米密度分布形式.计算结果表明，理论计算值对于没有奇异结构的核在低中能区和高能区，都与实验数据很好符合.     

辐射在相对论等离子体中非相干散射的结构因子

等离子体中粒子关联效应使辐射在等离子体内非相干散射的总截面等于汤姆逊截面乘上结构因子。本文给出辐射在相对论等离子体中非相干散射的结构因子。