3D Supramolecular Network Based on Hydrogen Bonds Between 1D [ Ni（μ2-C2O4） （ Him）2] Zigzag Chains

Introduction In recent years,considerable attention has been paid to supramolecular networks based on metal organic building blocks because of their potential applications in diverse fields,such as,catalysis,optics,sensors, magnetism,and molecular recognition[1-3].On the ba-     

Eco-friendly synthesis of high silica zeolite Y with choline as green and innocent structure-directing agent

Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure-directing agents (OSDAs), which are chronically hazardous to humans and the environment. It is a growing trend to develop an eco-friendly and nuisanceless OSDA for zeolite synthesis. Herein, choline is employed as a non-toxic and green OSDA to synthesize high silica Y zeolite with SiO₂/Al₂O₃ ratios of 6.5–6.8. The prepared Y zeolite samples exhibited outstanding (hydro)thermal stability at ultrahigh temperature owing to the higher SiO₂/Al₂O₃ ratio. The XRF, SEM, ²⁹Si-NMR and ¹³Na+ results suggested that choline plays a structure-directing role in the synthesis of Y zeolite, while the feed molar fraction of Na⁺ is a crucial determinant for the framework SiO₂/Al₂O₃ ratio and the crystal morphology.     

Nuclear Physics in Norway, 1933–1955

In the late 1940s and the 1950s, Norwegian nuclear scientists, engineers, and administrators were deeply split over their nation’s goals, organization, politics, and tools for research in nuclear physics. One faction was determined to build a nuclear reactor in Norway, while another fiercely opposed the reactor plans and focused on particle accelerators. The first faction comprised scientific entrepreneurs and research technologists, the second academic scientists, most of whom began their research careers in nuclear physics in the 1930s. To understand this conflict, I trace the development of nuclear research in Norway from the early 1930s to the mid-1950s, placing it within an international context. Roland Wittje is working on his habilitation thesis in the History of Science Unit at the University of Regensburg, Germany.     

Antioxidant activity of hydro distillation water residues from Rosmarinus officinalis L. leaves determined by DPPH assays

Rosemary (Rosmarinus officinalis L.) is a perennial herb with an intensive aromatic flavor. Its most important chemical constituents are essential oils (e.g., 1,8-cineole and camphor) and antioxidants (e.g., carnosic acid and rosmarinic acid). The common methods to extract the essential oil of rosemary are steam or hydro distillation. The aim of this work is to investigate the residual antioxidants after hydro distillation, especially rosmarinic acid and carnosic acid. For this purpose, the hydro distillation water residues were analyzed by HPLC-UV. Moreover, the influence of the extraction duration on the concentration of the antioxidants was investigated. Also, the residual amount of these compounds in the leaves was examined. The total antioxidant activity of the extracts and of the pure compounds was determined by DPPH assays. It is shown that after 2.5 h of hydro distillation the amount of rosmarinic acid and the antioxidant activity in the water residue reaches a maximum value. In addition, the yield and the quality of the essential oil were investigated to draw a comparison between steam and hydro distillations of Moroccan rosemary leaves.     

Effect of ultrasonic waves on the water turbidity during the oxidation of phenol. Formation of (hydro)peroxo complexes

Analysis of the kinetics of aqueous phenol oxidation by a sono-Fenton process reveals that the via involving ortho-substituted intermediates prevails: catechol (25.0%), hydroquinone (7.7%) and resorcinol (0.6%). During the oxidation, water rapidly acquires color that reaches its maximum intensity at the maximum concentration of p-benzoquinone. Turbidity formation occurs at a slower rate. Oxidant dosage determines the nature of the intermediates, being trihydroxylated benzenes (pyrogallol, hydroxyhydroquinone) and muconic acid the main precursors causing turbidity.It is found that the concentration of iron species and ultrasonic waves affects the intensity of the turbidity. The pathway of (hydro)peroxo-iron(II) complexes formation is proposed. Operating with 20.0–27.8 mg Fe²⁺/kW rates leads to formation of (hydro)peroxo-iron(II) complexes, which induce high turbidity levels. These species would dissociate into ZZ-muconic acid and ferrous ions.Applying relationships around 13.9 mg Fe²⁺/kW, the formation of (hydro)peroxo-iron(III) complexes would occur, which could react with carboxylic acids (2,5-dioxo-3-hexenedioic acid). That reaction induces turbidity slower. This is due to the organic substrate reacting with two molecules of the (hydro)peroxo complex. Therefore, it is necessary to accelerate the iron regeneration, intensifying the ultrasonic irradiation. Afterwards, this complex would dissociate into maleic acid and ferric ions.     

西南大渡河某水电站溢洪道陡槽段雾化边坡稳定性分析

泄洪雨雾入渗导致边坡变形进而影响边坡稳定性的问题已成水电建设的重要工程问题之一。针对西南某水电站溢洪道陡槽段边坡挤压错动带发育、节理裂隙和控制性结构面发育等结构特点,分析该边坡开挖支护后泄洪雾化条件下潜在失稳的边界条件及变形破坏模式。根据边坡所处的地质环境条件,从泄洪雾化对边坡岩体的作用机制入手,得到了雨雾对该边坡稳定性的影响主要为雨雾沿着顺倾坡外拉裂面入渗,影响结构面力学特性,从而影响边坡稳定性。并按结构面类型取不同软化系数,采用数值模拟方法分析了泄洪雨雾入渗后边坡的变形破坏趋势。分析结果表明：在考虑不同的软化系数时,溢0+555.00下游侧边坡岩体稳定性有较大的差别,若以中间值075考虑,溢洪道陡槽段边坡的稳定性稍差,可能产生一定规模的剪切蠕动变形或块体失稳,必须加强一定的支护措施保证该处边坡在施工期安全和运营期间的长期稳定性。     

卵清蛋白在疏水连续棒状色谱中吸附量与溶剂浓度间关系的研究

以推导改进的Langmuir模型过程中的总热力学平衡常数的表达式为基础,考察了卵清蛋白在疏水连续棒状色谱柱上的会行为,发现当蛋白在保留情况下,能很好地符合Langmuir模型,而且,进一步研究了吸附量与溶剂浓度的关系。发现在保留情况与,其吸附量的对数与流动相中置换剂的摩尔浓度之间在成线性关系。当流动相中硫酸铵浓度仅相关0．5mol/L时,其最大吸附量相差30倍,说明在比较柱的吸附量时,应选择适合的溶剂浓度,提出了在等浓度条件下洗脱条件蛋白能够在色谱柱保留时的饱和吸附量为其有效吸附量,在这种条件下的流动相的组成才是研究溶质饱和吸附量的合适组成。     

Spectrophotometric determination of carbon monoxide with ruthenium(II) octaethylporphyrin

A novel spectrophotometric method for the estimation of carbon monoxide at levels from 2 to 250 ppm is presented. The method is empirical and based on formation of a carbonyl complex of ruthenium(II) octaethylporphyrin and measurement of the difference in absorbance at 393.5 nm between this complex and the porphyrin reagent. Oxygen and nitrogen do not interfere and up to 300 ppm of sulphur dioxide and about 1500 ppm of carbon dioxide can be tolerated in determination of carbon monoxide at the 4 and 10 ppm levels. Hydrogen sulphide interferes and must be removed before the determination. The method has been tested over the range 2-45 ppm of carbon monoxide with 16 synthetic and 2 commercial standard air samples. The average error was +/- 3%. Application to urban-air samples and car-exhaust gases yielded acceptable results. The main disadvantages are the tedious preparation of the initial ruthenium(III)-porphyrin compound and the decomposition of the reagent in the presence of hydrazine.     

Organically‐Templated Zinc and Thorium Sulfates with Chain and Layered Structures

Amine‐templated zinc sulfates of the formulae, [Zn(SO₄)(H₂O)₂(C₁₀N₂H₈)] ( I ) and [C₃N₂H₁₂][Zn(SO₄)] ( II ) both with linear structures have been prepared under hydro/solvothermal conditions. Of these, I has the chain structure formed by ZnO₄N₂octahedra and SO₄ tetrahedra, while II comprises ladders formed by corner‐sharing four‐membered rings. Amine‐templated thorium sulfates of the formula [HN(CH₂)₆NH]₂[Th₂(SO₄)₆(H₂O)₂]·2H₂O, ( III ) and [H₂N(CH₂)₄NH₂][Th₃(SO₄)₇(H₂O)₄]·5H₂O ( IV ) are also obtained under hydrothermal conditions. III has a sheet structure consisting of cages whereas IV has a two‐dimensional structure derived from the connectivity of ladders.     

Assembly and structures of five new Cu(II) complexes based on the V-shaped building block [Cu(dbsf)]

Five new copper(II) complexes [Cu(dbsf)(H₂O)]_n · 0.5n(i-C₃H₇OH) (1), [Cu(dbsf)(4,4′-bpy)_0.5]_n · nH₂O (2), [Cu(dbsf)(2,2′-bpy)(H₂O)]₂ · (n-C₃H₇OH) · 0.5H₂O (3), [Cu(dbsf)(phen)(H₂O)]₂ · 1.5H₂O (4) and [Cu(dbsf)(2,2′-bpy)(H₂O)]_n · n(i-C₃H₇OH) (5) (H₂dbsf = 4,4′-dicarboxybiphenyl sulfone, 4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, i-C₃H₇OH = isopropanol, n-C₃H₇OH = n-propanol) have been synthesized under hydro/solvothermal conditions. All of the complexes are assembled from V-shaped building blocks, [Cu(dbsf)]. Complex 1 is composed of 1D double-chains. In complex 2, dbsf²⁻ ligands and 4,4′-bpy ligands connect Cu(II) ions into catenane-like 2D layers. These catenane-like 2D layers stack in an ABAB fashion to form a 3D supramolecular network. Complexes 3 and 4 are 0D dimers, in which two [Cu(dbsf)] units encircle to form dimetal macrocyclic molecules. However, in complex 5, the V-shaped building blocks [Cu(dbsf)] are joined head-to-tail, resulting in the formation of infinite tooth-like chains. The different structures of complexes 3 and 5 may be attributed to the different solvent molecules included.