[en] The photodetachment cross section formula for H^- in parallel electric and magnetic fields is derived, based on the close-orbit theory. By using the Poisson summation formula, the connection between the quantum and semiclassical results is made using a stationary-phase approximation and it is shown that each stationary-phase point corresponds to a closed orbit. The process of reduction can give the classical bifurcation energies correctly. The connection of the full quantum formula to the semiclassical one can be ascribed to the boundary effect of the stationary-phase integral

[en] Highlights: • Performance of NV-CAES with turbines is analyzed under sliding pressure mode. • Turbines for NV-CAES designed with precise 1-D design curve method are studied. • GNV-CAES presents 4.94% higher exergy efficiency and reduces the exergy destruction of 5.86 GJ. • NV-CAES with Turbine B shows lowest exergy destruction. • Proper choice on design condition of turbine under sliding pressure mode is proposed. A high-pressure stage turbine will discharge energy under sliding pressure mode in compressed air energy storage system (CAES) if without throttle valve installed upstream the turbine (NV-CAES). In this work, four high-pressure stage turbines A∼D are designed for NV-CAES with 1-D turbine loss model under four inlet pressures of 5.0 MPa, 7.0 MPa, 9.0 MPa and 11.0 MPa, respectively. Simulation results reveal that Turbine B has relatively wider working operation range and higher performance. Then, another high-pressure stage turbine in NV-CAES is designed with General performance curve (GNV-CAES) under inlet pressure 7.0 MPa. Both thermodynamic model and exergy efficiency model were built to simulation system performance of these NV-CAESs. For comparison, a CAES equipped with throttle valve (V-CAES), in which the turbine train works with constant inlet pressure, is also computed. Compared with V-CAES, GNV-CAES reduces the exergy destruction from 52.25 GJ to 46.29 GJ and improves the exergy efficiency by 3.3%. The thermodynamic comparison among NV-CAESs shows that The CAES with Turbine B shows the best performance with the storage pressure of 4.0–13.0 MPa. Thus, properly choosing design conditions of high-pressure stage turbine plays an important role to enhance performance of CAES with sliding pressure discharging mode.

[en] The International Nuclear and Radiological Event Scale is intended to inform the public about the safety implications of nuclear facility events. Since the establishment of the National Nuclear Safety Administration of China, this scale has been used to grade and assess the events of civilian nuclear facilities. In the field of nuclear power, since the loading of QinShan Nuclear Power Station, the first nuclear power plant in China in 1991, the classification table has been used to grade the operational events occurring in nuclear power plants. With the increase in the number of nuclear power plants operating in China, the number of operational events has gradually increased, and the use of international nuclear and radiological event scales in nuclear power plants has become more frequent and widespread. This paper introduces the development history, scope of application, general description and grading criteria of the international nuclear and radiological event scale, and discusses the application of the scale in the event of nuclear power plants in China, so as to provide reference for the classification of important events in China's nuclear power plants. (authors)

[en] Highlights: • B, E and v increase as pressure increases, except for a sudden decrease at 40 GPa. • WSe₂ under pressure has larger shear modulus and higher hardness than WSe₂ at 0 GPa. • WSe₂ has an isostructural semiconductor-semimetal phase transition at 40 GPa. • The covalent bonding between Se and W atoms in the slabs is enhanced under pressure. • The distance of the stacked Se–W–Se slabs is decreased with the increasing pressure. - Abstract: Effect of pressure on elastic, mechanical and electronic properties of WSe₂ has been investigated using the first-principles calculations. The calculated lattice parameters, band structure and elastic constants of WSe₂ at 0 GPa are in good agreement with the available experimental and calculational values. With the increasing pressure, the lattice parameters and volume of WSe₂ decrease whereas the total enthalpy increases. The bulk modulus, Young's modulus and Poisson's ratio of WSe₂ increase with the increasing pressure, except for a sharp decrease at the pressure of 40 GPa. WSe₂ under pressure has larger shear modulus and higher hardness than WSe₂ at 0 GPa. With the increase of pressure, the covalent bonding between Se and W atoms in the slabs is enhanced whereas the distance of the stacked slabs is decreased. Additionally, an isostructural semiconductor-semimetal phase transition of WSe₂ is found to take place at 40 GPa, which is consistent with the experimental observations

[en] Highlights: • Bisphenol A promoted cell growth and photosynthesis at lower phosphorus level. • Phosphorus sufficiency and BPA caused oxidative stress. • Phosphorus sufficiency and BPA stimulated production and release of MCs. • Photosynthesis and fatty acid biosynthesis were up-regulated under BPA stress. • Two-component system and cell cycle-caulobacter were inhibited by BPA. -- Abstract: Microcystis aeruginosa is known as the main contributor to cyanobacterial bloom, which is prevalent globally and degrades freshwater systems worldwide. The argument that the introduction of anthropogenic contaminants in fresh water stimulates cyanobacterial growth and microcystin production has attracted widespread attention. Bisphenol A (BPA), one of the most abundant endocrine-disrupting compounds, is often detected in various water bodies due to its notably high annual levels of production and use. Research on the combined effects of endocrine-disrupting compounds and environmental factors on cyanobacteria remains limited. To investigate the mechanism of interactions between contaminants and cyanobacteria at the cellular and proteomic levels, the growth rate, chlorophyll-a content, photosynthetic activities, microcystin-LR (MC-LR) production and release, reactive oxygen species (ROS) content, superoxide dismutase (SOD) activities, malondialdehyde (MDA) content, and proteome expression of M. aeruginosa under 1 μM BPA stress at a standard phosphorus level were investigated. The results showed that stress responses to BPA included increases in the growth rate, chlorophyll-a content, and Fv/Fm and rETRmax values under the low phosphorus condition. Responses involving ROS, SOD, and MDA indicated that phosphorus sufficiency and BPA caused oxidative stress in M. aeruginosa. Moreover, phosphorus sufficiency and BPA stimulated the production and release of MCs. Compared to levels in the non-BPA-treated group, exposure of M. aeruginosa to BPA caused 72 up-regulated proteins, which were primarily associated with photosynthesis, ribosome, fatty acid biosynthesis, glycolysis/glyconeogenesis, and carbon fixation in photosynthetic organisms. The 105 down-regulated proteins were related to quorum sensing, base excision repair, ABC transporters, longevity regulating and cell cycle-caulobacter, suggesting that the cytotoxicity of cyanobacterial cells induced by BPA was significantly increased. These findings provide insights into the molecular mechanism of the effects of BPA and phosphorus on M. aeruginosa, suggesting that coexisting pollutants may cause greater harm to and health risks in the environment.

[en] Highlights: • Solubility were determined for dehydroepiandrosterone acetate in nine solvents. • Solubility were correlated with four thermodynamic models. • Apparent standard enthalpy and excess enthalpy of solutions were evaluated. - Abstract: The solubility was measured for dehydroepiandrosterone acetate in cyclohexane, acetone, ethyl acetate, acetonitrile, methanol, 1-butanol, ethanol and isopropanol by high-performance liquid chromatography analysis under the pressure of 101.3 kPa. The temperature of the determination varied from (273.15 K to 318.15) K. The dehydroepiandrosterone acetate solubility increased with the increase in temperature, and obeyed the following order from high to low: ethyl acetate > acetone > 1-butanol > acetonitrile > (cyclohexane, isopropanol) > ethanol > methanol. They were correlated with four models, viz. the modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest average standard deviation is 5.93 × 10"−"4, and the largest relative average deviation is 1.18% for each set of solubility values. The calculated solubility was in good agreement with the experimental values for the four models. Moreover, the thermodynamic properties of the solution process, including the apparent standard dissolution enthalpy and excess enthalpy were calculated. The experimental solubility, thermodynamic models and thermodynamic properties are very important in the purification process of dehydroepiandrosterone acetate.

[en] Six new coordination polymers, [ZnLCl]_n(1), [ZnL_2]_n·2nH_2O (2), [Zn_2L(o-bdc)(OH)]_n·0.5nH_2O (3), [Zn_2L(m-bdc)(OH)]_n·nH_2O (4), [Zn_2L_2(p-bdc) (H_2O)_2]_n·nH_2O (5), [Zn_2L(1,2,4-btc)(H_2O)]_n(6), (HL=4′-(3-carboxyphenyl)- 3,2′:6′,3″-terpyridine, H_2(o-bdc)= benzene-1,2-dicarboxylic acid, H_2(m-bdc)= benzene-1,3-dicarboxylic acid, H_2(p-bdc)= benzene-1,4-dicarboxylic acid, H_3(1,2,4-btc)= benzene-1,2,4-tricarboxylic acid) have been synthesized under the hydrothermal conditions. Compound 1 displays a 3-connected 2D network structure with point symbol of {8"2.10}. Compound 2 exhibits 1D infinite loop chain structure. Compound 3 possesses a (3,8)-connected 3D framework composed of tetranuclear units with point symbol of {4"3}_2{4"6.6"1"8.8"4}. Compound 4 features a typical 2D hcb network based on tetranuclear zinc(II) units with point symbol of {4"4.6"2}. Compound 5 presents a classical two-fold penetration sql network with point symbol of {6"3}. Compound 6 can be seen as a (3,3,6)-connected 3D net with point symbol of {4"2.6"4.8"9}{4"2.6}{6"3}. The thermal stability and luminescent properties of compounds 1–6 in the solid state are discussed in detail. - Graphical abstract: Six new Zn(II) coordination polymers based on multicarboxylate and terpyridyl derivative ligands have synthesized under the hydrothermal conditions and the thermal stability and luminescence are discussed. Display Omitted

[en] Highlights: • Bisphenol A inhibited cyanobacterial cell growth and promoted photosynthesis. • Nitrogen deficiency and bisphenol A caused oxidative stress. • Nitrogen sufficiency and bisphenol A stimulated production of microcystins. • Photosynthesis and nitrogen metabolism were up-regulated by bisphenol A stress. • Quorum sensing and cell cycle-caulobacter pathway were inhibited by bisphenol A. -- Abstract: Microcystis aeruginosa is known as a main contributor of cyanobacterial bloom. However, factors that drive its formation and dispersion remain poorly understood. The cellular-level responses to nutrient drivers of eutrophication were investigated. The results showed that growth rate of M. aeruginosa was significantly enhanced with the increasing bisphenol A (BPA) and nitrogen (N) level. Stress of BPA significantly inhibited cellular density, chlorophyll-a content across all the nutrient conditions, while Fv/Fm and rETRmax value were promoted by BPA. Responses of reactive oxygen species (ROS) value, superoxide dismutase (SOD) activity and malodialdehyde (MDA) content indicated that nitrogen deficiency and BPA caused oxidative stress to M. aeruginosa. Besides, nitrogen and BPA regulated the production and release of microcystins (MCs). M. aeruginosa exposed to BPA caused 95 up-regulated proteins, which was primarily associated with photosynthesis, nitrogen metabolism, glycolysis/glyconeogenesis and carbon fixation in photosynthetic organisms. The 91 down-regulated proteins were related to quorum sensing, longevity regulating and cell cycle-caulobacter, confirming that the driving force of regulating the change of cellular density and genes expression weakened. These findings provide important clues to elucidate the combined regulatory mechanisms of cyanobacterial blooms triggered by endocrine-disrupting compounds and environmental factors and help to effectively prevent and reduce cyanobacterial blooms.

[en] Nine new lanthanide coordination polymers, namely, [Ln(Hsfpip)(ox)_0.5(H₂O)]_n·2n(H₂O) ((Ln=Eu (1), Tb (2), Dy (3), Ho (4), Er (5), Yb (6), Y(7)), [Ln(H₂sfpip)(ox)(H₂O)₄]_n·2n(H₂O) (Ln=Nd (8) Sm (9)), [H₂ox=oxalic acid, H₃sfpip=2-(2,4-disulfophenyl)imidazo(4,5-f)(1,10)-phenanthroline] have been synthesized under hydrothermal conditions and characterized by IR spectra, elemental analysis, powder X-ray diffraction and single crystal X-ray diffraction. When sodium oxalate is added, the reactions of lanthanide ions with H₃sfpip resulted in two types of structures. Compounds 1–7 are obtained at pH 5.0 and exhibit 3D tfz-d networks with ox²⁻ anions as linkers to bridge the adjacent layers. Compounds 8–9 are obtained at pH 2.0, and display a 1D chain which is further extended to a 3D supramolecular framework through intermolecular hydrogen bonds and π-π interactions. The structural variation from compounds 1–7 to 8–9 can attribute to the pH effect on construction of lanthanide coordination polymers. Moreover, the thermal stabilities and luminescence properties of 1–9 were also investigated. - Graphical abstract: Nine new lanthanide coordination polymers have been synthesized under hydrothermal conditions. Compounds 1–7 exhibit a 3D tfz-d network. Compounds 8–9 display a 1D chain structure. The structural variation from compounds 1–7 to 8–9 can attribute to the pH effect on construction of lanthanide coordination polymers. - Highlights: • Nine lanthanide coordination polymers were prepared under hydrothermal conditions. • Their crystal structures have been determined. • The luminescence and thermal stabilities were studied in the solid state.

[en] The conventional high power microwave (HPM) radiation measurement system often consists of antennas, attenuators, detectors and other components. There will always be parametric selection dilemma when the conventional system is used in HPM beat-wave radiation measurement, because the system is designed and tested on single frequency while beat-wave signal is composed of many frequency components. Furthermore, the utilization of detectors in beat-wave radiation measurement will lead to new beat-wave frequency components due to their nonlinear feature. It is commonly difficult to measure the output waveform accurately when the signal is superimposed with the new beat-wave frequency components. To solve these problems, a new measurement method based on frequency separation and electric field backstepping is proposed. The application of the proposed method is able to effectively reduce uncertainty of beat-wave radiation measurement to less than 0.3 dB, which satisfies the requirement of accurate HPM beat-wave radiation measurement. (authors)