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A three-dimensional (3D) multiscale phase field model was proposed to investigate the effect of Ca, Y and Al solutes on the texture evolution of ZK60 alloy during grain growth at 573 K under an applied compression stress of 270 MPa, in which the characteristics of the elastic anisotropy and grain boundary (GB) segregation caused by the solutes were taken into account. The results show that either Ca or Y addition can weaken the basal texture of ZK60, while Al addition enhances it. The deviation of the grain size distribution from the Hillert model becomes greater with the addition of Al, while Ca or Y addition reduces the deviation. The solute segregation-induced GB energy change has a very limited effect on the texture evolution compared with elastic anisotropy. The revealed mechanism is of great significance for the microstructure design of the ZK60 alloy by an appropriate alloying strategy.

The actual effective partition coefficients of Mg and Cr in a cross-section of a dendrite arm in a direct-chill (DC)-casting ingot of 7475 aluminum alloy are obtained. Meanwhile, by analyzing the microstructure, the mechanism of the heterogeneous distribution of E(Al18Mg3Cr2) dispersoids in this DC ingot is revealed. The results show that the actual effective partition coefficients of Mg and Cr are 0.650 and 1.392, respectively, and they describe the heterogeneous distributions of Mg and Cr along the direction of radius of the cross-section of the dendrite arm of the alloy. After homogenization treatment at 470 °C for 24 h, Mg diffuses uniformly, but Cr hardly diffuses. Both the concentrations of Mg and Cr and the sites of heterogeneous nucleation in the alloy are the determinants of the formation of Edispersoids simultaneously. The heat treatment at 250 °C for 72 h provides a large number of the sites of heterogeneous nucleation of the formation of fine Edispersoids that will be formed in the center of the cross-section during the subsequent heat treatment at higher temperature.

Central region coarse grains and centerline segregation are common defects in aluminum ingots fabricated by direct chill (DC) casting. A double cooling field was introduced into the DC casting process to reduce these defects, whereby the external cooling was supplied by the mold and water jets, and intercooling was achieved by inserting a rod of the same alloy into the molten pool along the central axis of the ingot. Rather than forming a good metallurgical interface during solid-liquid compound casting, in the present work, the purpose of inserting the rod is to enforce internal cooling and consequently decrease the sump depth. Moreover, the insertion provides more nucleation sites with the unmolten α-Al particles. The structure and the macrosegregation of 2024 Al alloy ingots prepared by DC casting with and without the inserts were investigated. Results show that when the inserting position is 50 mm above the upper edge of the graphite ring, significant grain refinement in the central region of the ingot and a reduced centerline segregation are achieved.

Laser Shock Peening (LSP) was introduced to reduce the residual stress and improve the wear and corrosion resistance of Fe-based 43X coating on worn U71Mn steel by laser cladding technology. The tensile stress decreased with increasing of laser power density and impact times, finally, transferred to compressive stress. The microstructure of the coatings was refined due to LSP treatment. The refined microstructure and existence of retained Austenite phase resulted in significant improvement in microhardness and anti-wear performances. The coatings after LSP process presented better corrosion resistance. However, impact three times with a higher power density has negative effect on improving the corrosion resistance.

Estazolam (EST) is a common sedative-hypnotic drug with a risk of abuse. Therefore, rapid on-site detection of EST is necessary to control the abuse of EST. In this paper, a fast, simple, and sensitive method is demonstrated for the detection of EST in both water and beverages, using surface-enhanced Raman spectroscopy (SERS) techniques. Au@Ag core-shell nanoparticles (NPs) assembled on the filter paper as a SERS substrate exhibit good applicability and practicality. At the same time, density functional theory (DFT) is used to assign the vibration mode of the EST molecules, which can be used as a guide for subsequent experiments. The lowest detectable concentration of EST in aqueous solution can be as low as 5 mg/L, and signal uniformity is excellent (RSD687= 5.56%, RSD1000= 4.35%). In addition, EST components artificially added to orange juice and pomegranate juice can be effectively detected by simple pretreatment with a minimum detection concentration as low as 10 mg/L. Therefore, this study found that the use of Au@Ag core-shell nanoparticles paper-based SERS substrate provides a quick and easy method for the detection of illegally added drugs in beverages.

Surface-enhanced Raman spectroscopy (SERS) has gradually proved to be a powerful tool with wide applications in various fields. Here, a simple and rapid SERS method was developed for the determination of ketamine in urine based on silver aggregates as a SERS substrate. Ketamine in urine were demonstrated by the SERS technique with silver sol aggregated by a 0.5 M NaBr solution. The limit of detection for ketamine in urine could be obtained as low as 7.5 ppm, and a linear relationship for ketamine in urine between the Raman intensity and the concentrations was achieved in the range from 7.5 to 150 ppm (R2= 0.977). Additionally, the recovery of this method ranged from 95.7 to 104.9%, which laid a favorable foundation for the rapid and reliable quantitative detection of ketamine in urine. Therefore, this SERS approach with high sensitivity and simplicity has a great prospect for the real-world application of ketamine in urine.

A nanocrystalline TiN graded coating was prepared on Ti6Al4V alloy by DC reactive magnetron sputtering method. The microstructure and mechanic properties of the coating were investigated. The electrochemical corrosion and tribocorrosion of the coated specimens in physiological environment were compared with those of Ti6Al4V substrate. The results show that the gradient distribution of nanocrystalline TiN is favorable for releasing the inner stress in the coating, which increases adhesion strength to 90 N. The compact structure and refined-grains of the coating result in the surface nanohardness of 28.5 GPa. The corrosion protection efficiency of the nanocrystalline TiN coating reaches 96.6%. The tribocorrosion resistance of the coating increases by 100 times in comparison with that of Ti6Al4V substrate. The high chemical stability and H3/E2ratio (where His hardness, and Eis elastic modulus) of the nanocrystalline TiN coating are responsible for good corrosion and wear resistances.

In this investigation, surface-enhanced Raman spectroscopy (SERS) technology was performed to detect bucinnazine hydrochloride (BH) injection in water and urine. The theoretical Raman spectrum of BH with characteristic peaks was calculated and identified by density functional theory (DFT). Employing an improved silver sol as a SERS active substrate, the SERS spectra of a BH solution with different concentrations were acquired with a 0.5 mol/L KI solution as an aggregation agent. It was determined that the limit of detection (LOD) was low, to 0.01 μg/mL. A good linear relationship of BH between the Raman intensity and the concentrations was obtained in water at a concentration range from 0.5 to 6 μg/mL (R2= 0.9914), which laid a favorable foundation for quantitative analysis. In addition, the recovery rate of spiked samples from 95.13 to 120.54% were calculated. Finally, the detection of BH injection in artificial urine was completed and the detection limit could reach 0.5 μg/mL, which met the requirements of a rapid on-site detection of drugs in urine. As a result, it indicates that the inspection of BH by the SERS method is with simplicity and high sensitivity, having a great potential for real-time detection.

Mg–Zn–Ag alloys have been extensively studied in recent years for potential biodegradable implants due to their unique mechanical properties, biodegradability and biocompatibility. In the present study, Mg–3Zn-xAg (wt%, x= 0.2, 0.5 and 0.8) alloys with single-phase crystal structure were prepared by backward extrusion at 340 °C. The addition of Ag element into Mg–3Zn slightly influences the ultimate tensile strength and microstructure, but the elongation firstly increases from 12% to 19.8% and then decreases from 19.8% to 9.9% with the increment of Ag concentration. The tensile yield strength, ultimate tensile strength and elongation of Mg–3Zn–0.2Ag alloy reach up to 142, 234 MPa and 19.8%, respectively, which are the best mechanical performance of Mg–Zn–Ag alloys in the present work. The extruded Mg–3Zn–0.2Ag alloy also possesses the best corrosion behavior with the corresponding corrosion rate of 3.2 mm/year in immersion test, which could be explained by the single-phase and uniformly distributed grain structure, and the fewer twinning.

The degradation behaviors of the as-extruded and solution treated Mg-3Zn-xAg (x=0, 1, 3, mass fraction, %) alloys, as well as as-extruded pure Mg, have been investigated by immersion tests in simulated body fluid (SBF) at 37 °C. The as-extruded Mg-Zn(-Ag) alloys contained Mg51Zn20and Ag17Mg54. While the quasi-single phase Mg-Zn(-Ag) alloys were obtained by solution treatment at 400 °C for 8 h. The quasi-single phase Mg-Zn(-Ag) alloys showed lower degradation rate and more homogeneous degradation than corresponding as-extruded Mg alloys. Degradation rate of solid-solution treated Mg-3Zn-1Ag and Mg-3Zn-3Ag was approximately half that of corresponding as-extruded Mg alloy. Moreover, the degradation rate of solid-solution treated Mg-3Zn and Mg-3Zn-1Ag was equivalent to that of as-extruded pure Mg. However, heterogeneous degradation also occurred in quasi-single phase Mg-Zn-Ag alloys, compared to pure Mg. So, preparing complete single-phase Mg alloys could be a potential and feasible way to improve the corrosion resistance.

Surface-enhanced Raman spectroscopy (SERS) was used to measure scopolamine hydrobromide. First, the Raman characteristic peaks of scopolamine hydrobromide were assigned, and the characteristic peaks were determined. The optimal aggregation agent was potassium iodide based on a comparative experimental study. Finally, the SERS spectrum of scopolamine hydrobromide was detected in aqueous solution, and the semi-quantitative analysis and the recovery rate were determined viaa linear fitting. The detection limit of scopolamine hydrobromide in aqueous solution was 0.5 μg/mL. From 0–10 μg/mL, the curve of the intensity of the Raman characteristic peak of scopolamine hydrobromide at 1002 cm−1is y= 4017.76 + 642.47x. The correlation coefficient was R2= 0.983, the recovery was 98.5–109.7%, and the relative standard deviation (RSD) was about 5.5%. This method is fast, accurate, non-destructive and simple for the detection of scopolamine hydrobromide.

In the present work, Zn–(0–1)Mg (wt%) alloys were prepared by casting and indirect extrusion at 200 and 300 °C, respectively. With Mg addition, both the size and amount of second phase Mg2Zn11increased, and the equiaxed grains were significantly refined. The extrusion temperature had little influence on Mg2Zn11, but the grains were refined at low extrusion temperature. For the alloys extruded at 200 °C, as Mg content increased, the tensile yield strength (TYS) increased from 64 MPa for pure Zn to 262 MPa for Zn–1Mg; the elongation increased from 14.3% for pure Zn to 25% for Zn–0.02Mg and then decreased to 5% for Zn–1Mg. For the alloys extruded at 300 °C, as Mg content increased, the TYS increased from 67 MPa for pure Zn to 252 MPa for Zn–1Mg, while the elongation decreased from 11.7% to 2%. The alloy extruded at 200 °C exhibited higher TYS and elongation than the corresponding alloy extruded at 300 °C. The combination of grain refinement and second phase Mg2Zn11contributed to the improvement in the TYS, and the grain refinement played a major role in strengthening alloy. Zn–0.02Mg and Zn–0.05Mg alloys extruded at 200 °C show a mixture of cleavage and ductile fracture corresponding to higher elongation, while the other alloys show cleavage fracture.

Diazepam injection was detected based on a droplet surface enhanced Raman spectroscopy (SERS) platform, which overcomes the disadvantages of the poor uniformity and time-consuming sample treatment process of the conventional “drop and dry” detection strategy. The Raman peak positions of diazepam injection were determined and identified, they are mainly located in the 689, 1002, 1170 and 1598 cm–1, etc. Different concentrations of diazepam injection were detected. It was found that the intensity of 1002 cm–1increases linearly with concentration in the range from 0.05 to 10 μg/mL and the linear correlation coefficient is 0.988. The limit of detection can reach 0.05 μg/mL. The SERS method is easy, fast and efficient. The results are accurate and reliable. It has favorable application potential in the detection of diazepam injection.

In this present work, TiN films with various thicknesses (from 0.3 μm to 2 μm) were deposited by DC reactive magnetron sputtering on Ti6Al4V substrates. The evolution of texture and microstructure were studied by X-ray diffraction and Scanning Electron Microscopy, respectively. The XRD characterization indicates that the preferred texture of TiN films is changed from (111) to (100) with increasing the film thickness. The microstructure characterization shows that their microstructure transform from continuous into columnar with increasing the TiN film thickness. It is considered these results are arised from the change of overall energy including surface energy and strain energy with the film thickness. The hardness of TiN film increases with increasing the film thickness.

BiVO4/Bi2VO5.5 heterogeneous nanostructures with enhanced visible light photocatalytic activity were successfully prepared by a facile one-pot solvothermal method, where diethylene glycol (DEG) was used as the solvent. The as-prepared products were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectrometry (XPS) and UV-Vis absorption spectroscopy. The results revealed that the molar ratio of Bi3+ to VO43- played an important role in the formation of crystal and morphology. These BiVO4/Bi2VO5.5 heterogeneous nanostructures exhibited higher visible-light-driven photocatalytic efficiency compared to the pure BiVO4 and Bi2VO5.5. For the methyl orange (MO) degradation efficiency of BiVO4/Bi2VO5.5 heterogeneous nanostructures under visible light irradiation, about 95% of MO was degraded within 40min, which is much higher than pure BiVO4 and Bi2VO5.5. The enhancement of photocatalytic activity can attribute to the promoted light absorption capability and the separation efficiency of photo-generated electron-hole pairs.

Two group chromophores with strong methoxy electron donor and CF3 electron acceptor were synthesized and reported. To investigate the effects of conjugative bond and its length between electron donor and acceptor on optical properties, thiophene ring was incorporated into the conjugated units of group B compared to group A. The results showed that the incorporation of thiophene rings could significantly enhance molecular first hyperpolarizability and permit a high thermal stability. It has been found that molecular first hyperpolarizability increased continually by the increase of bond length of group A. However, further increase of conjugated bond length between electron donor and acceptor in group B reduced the molecular hyperpolarizability. This study indicates that both the nature of the conjugative bridge and its bond length between electron donor and acceptor have inner correlation to optimize the molecular hyperpolarizability for electro-optical applications.

Soft magnetic Fe-B-P ultrafine particles with amorphous structure were prepared by aqueous reduction method with variable pH values. The microstructure, compositions and the soft magnetic properties of Fe-B-P submicron particles were investigated by using field emission scanning electron microscope (FE-SEM), X-Ray Diffraction (XRD), mössbauer spectrum (MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), vibrating sample magnetometer (VSM). The results showed that a series of Fe-B-P amorphous particles with the average particle size of 0.26~0.42 μm were obtained depending on the pH value of solution. As pH value increased, the contents of B and P increased, and the specific saturation magnetization of the Fe-B-P submicron particles decreased. Some electrons, transferred from p-shell of B atoms and P atoms to 3d-shell of Fe atom, resulted in the decrease of the number of unpaired electron, which in turn led to reduction of the average hyperfine magnetic field of the Fe-B-P particles and the decrease of the magnetic torque of Fe atoms. The relation between hyperfine magnetic field (Hhf) and the specific saturation magnetization was in accord with the Marshall’s equation. At the same time, the enhancement of the shielding effect on 4s electron orbital, i.e., the density of 4s electron reduced, leading to the increase of Isomer Shift.

Surface-enhanced Raman spectroscopy (SERS) was used for detecting Rhodamine B (RB) which is often added illegally to chili powder. Based on density functional theory, the Raman spectrum of RB was calculated and characteristic peaks of RB were assigned to the corresponding vibrational modes. RB was detected utilizing paper-based SERS substrates which were fabricated viaa liquid–liquid interface-mediated self-assembly technique. Meanwhile, with simple sample pretreatment, the detection limit could reach 10−6g g−1for RB in chili powder (5 × 10−7g mL−1in extraction agent). Within the concentration range from 10−2g g−1to 10−6g g−1, Raman intensity follows a certain function in relation to the concentration of RB. The recovery of this method ranges from 96.4% to 108.9%, which gives rapid and reliable quantitative detection of RB in chili powder. Therefore, the proposed SERS method is suitable for on-site detection and analysis of RB in chili powder.

A portable Raman spectrometer was used for the rapid detection using surface-enhanced Raman spectroscopy (SERS) of pethidine hydrochloride injection by employing a silver colloid as the SERS active substrate. Different substrates and aggregation agents were investigated in order to explore the optimum conditions for the SERS detection of pethidine hydrochloride injection. Under the optimum experimental conditions, excellent reproducibility and stability of SERS detection was guaranteed. In addition, the limit of detection (LOD) for pethidine hydrochloride injection in water was low at 0.1 μg mL−1with an analytical enhancement factor of 5.3 × 104, which is extremely far below typical administered dosages (50 mg mL−1). Finally, a good linear relationship between the Raman intensity and concentration was obtained for pethidine hydrochloride injection in water at a concentration range from 0.1 to 10 μg mL−1(R2= 0.999), which lays a favourable foundation for the semi-quantitative analysis of the concentration of pethidine hydrochloride injection. In general, the capabilities reported here demonstrate that the SERS method is convenient, rapid and efficient, and has good potential in clinical applications for point-of-care detection and real-time monitoring.

The phase equilibria and compositions at the Mg-rich corner of the Mg–Zn–Al ternary system at 335 °C were systemically investigated through the equilibrated alloy method by using X-ray diffraction (XRD) and scanning electron microscopy (SEM) assisted with energy dispersive spectroscopy of X-ray (EDS). It is experimentally testified that the α-Mg solid solution is not in equilibrium with the Mg32(Al, Zn)49(τ) ternary intermetallic compound or qquasicrystalline phase, but only in equilibrium with one ternary intermetallic compound Al5Mg11Zn4(φ). The whole composition range of the φphase was also obtained at 335 °C, i.e., 52.5%–56.4% Mg, 13.6%–24.0% Al, 19.6%–33.9% Zn (mole fraction). The solubility of Al in the MgZn phase is remarkably more than that in the Mg7Zn3phase, and the maximum is about 8.6% Al. Aluminum and zinc are simultaneously soluble in the α-Mg solid solution.

Hematite is one of the most promising photoanodes for water splitting, but its photoelectrochemical (PEC) efficiency is still low. This work proved that the PEC efficiency of hematite can be improved by Ce doping. The Ce doped hematite was successfully prepared by co-sputtering CeO2 and Fe2O3, and followed by thermal oxidation treatment. The results of J-V test showed that the photocurrent of 5 at.% Ce doped α-Fe2O3 film can reached 1.35mA/cm2 in 1 M NaOH (pH=13.6) at 1.23V vs. NHE, which is nearly 15 times higher than the undoped one. The enhancement of PEC efficiency was proved by the enhancement of absorbance of visible light, as well as increased carrier density after Ce doping.

Cu2ZnSnS4 thin films were fabricated by one-step RF magnetron sputtering of a single quaternary Cu2ZnSnS4 (CZTS) chalcogenide target on Mo/soda lime glass substrate, followed by post sulfurization using S vapor obtained from elemental S powders. The films were thermally annealed in Ar atmosphere to improve the crytallinity. The sulfurization temperature was fixed at 550°C. Both as-deposited and post-sulfured samples are close to the stoichiometric composition, meanwhile without any second phase was detected by XRD. As-deposited film has a compact columnar grain characteristic. Although crystallinity was improved with increasing annealing time, this characteristic disappeared after post-sulfured.

α-helix and β-hairpin are the two principal secondary structures in proteins. A large number of experimental and theoretical kinetics and thermodynamics studies of the folding and unfolding of α-helix and β-hairpin structured polypeptides and proteins have been performed. Different theoretical models have been proposed to explain their folding mechanisms. Inconsistencies exist among the various models, which essentially reflect the different understanding of how individual structural elements affect the folding process and stability of protein structures. The present review mainly summarizes our recent simulation studies of the structure stability, folding and unfolding (denaturation) mechanism of various α-helix bundle and β-structure systems.

Natural frequencies are calculated for a short cylindrical shell based on semi-analytical method of transfer matrix, especially considering the structural effects of sealing teeth. The thin wall shell with some sealing teeth can be divided into finite segments where the diameters are different. According to the theory of the state vector expression of a structure cross-section, a first-order ordinary differential equation referring to state vectors of continuous segment sections of a short cylindrical shell is established based on governing equations of thin cylindrical shell. Then a total transfer matrix of the shell with sealing teeth is obtained after producing all the transfer matrices of all the segments. The boundary conditions investigated in the study are free-free, free-clamped and clamped-clamped of the two ends of the shell. The natural frequencies can be solved by precise integration of the differential equation of the whole shell with divided segments. The obtained numerical examples show that the sealing teeth have influence on the frequency values of higher circumferential modes, and they also have influence on the natural frequencies in different boundary conditions. The results by the proposed method are also compared with those of finite element method.

The relationship of the kinetic fundamental parameters for both the prototype and model are derived by employing the finite method. Based on the relations, the scaling laws of the thin walled cylinder for the free vibration are found by applying the similitude transformation to the governing equation. In the absence of the experimental data, the validity of the scaling laws is testified by numerical data. This is done by calculating theoretically the natural frequencies for free vibration of the cylinders. By substituting the model frequencies in the scaling laws, the frequencies of the prototype are obtained. Consequently, the frequencies of the model and prototype are compared. Examples that one end of the thin walled shell is clamped and the other is simply supported show exact agreement.

Thin films of hematite find extensive applications in photoelectrochemistry, photocatalysis, and gas sensors. c-axis oriented hematite films have been directly grown on c-plane sapphire substrate using chemical method via hydrolysis of ferric cations. X-ray diffraction (XRD) reveals that the crystalline phases of the films and corresponding sediment produced in the solution were α-Fe2O3 and pure β-FeOOH, demonstrating the promotion of nucleation of hematite on sapphire substrate as a result of lowered interface energy. Phi-scan results indicate that the hematite films are grown with (0001) planes parallel to c-plane of Al2O3. Scanning electron microscopic observation shows that the hematite films are composed of pyramid-shaped nanocrystals with smooth surface facets.

In the service of sliding isolated structure, the slip component damage degree determines the safety of sliding isolated structure. The seismic response analysis about a sliding isolated frame structures was obtained by the finite element analysis software SAP2000 at various loads and compared with the traditional structure. Seismic response differences between slip component of the different forms and number damage was studied. According to Teflon invalid and the displacement-limited of energy dissipation component invalid, the impact of seismic response owing to slip component damage was analyzed. It will provide a reference for the isolated building design, the effective maintenance and damage detection.

The equilibrium phase relationships and compositions of Ni - 51at.%Al/Ni - 26at.%Al diffusion couple heat treated at 650 ℃ for various times have been investigated by means of diffusion couple technique. Experimental results showed that Ni5Al3 phase was not only stable at 650 ℃, but also had a large solubility range (45.3～40.6) at.% Al. The obtained relationships of NiAl/Ni5Al3 and Ni5Al3/Ni3Al are in accordance with the current generally accepted Ni-Al binary system phase diagram, but their composition ranges are quite different from the presently accepted one, that is, the the phase boundaries of NiAl / (Ni5Al3 + NiAl), (Ni5Al3 + NiAl) / Ni5Al3 and Ni5Al3 / (Ni3Al + Ni5Al3) significantly shift to the Al-rich side.

Intergranular exchange coupling between magnetic nano-grains is one of important parameters to develop magnetic recording media towards the areal density of 1000 Gbits/in2. In this presentation, various processings, involving oxide co-sputtering for perpendicular media, spontaneous phase separation for longitudinal media, and grain boundary (GB) diffusion derived from underlayer or overlayer to induce tunable exchange coupling, have been reviewed to tailor the exchange coupling, including their main principles, present achievements and engineering challenges. Much attention is paid to the physical origin of magnetically induced phase separation of Co-Cr-based alloy, which governs media noise and coercivity, and its applications to the longitudinal media. A proposal of GB diffusion is also highlighted in detail to show a feasibility to tailor the exchange coupling, including calculation results and experimental evidences.

Cement is an important building material with high energy consumption and high emission, while energy conservation and emission reduction has been the consensus over the world in the background of the global climate warming. Aiming at the problems of large cement consumption and long construction period of deep mixing column, a double-liquid curing agent composed of low thickness cement slurry and sodium silicate solution is proposed to replace cement slurry in deep mixing columns. The installation equipment is modified to adapt to the double-liquid curing agent. The effect of the double-liquid curing agent is researched through filed tests, which verify the environmental and economic benefits in cement saving and construction accelerating. The double-liquid curing agent for deep mixing columns has great promotion potential.

Abstract Lacustrine deposits exposed at Daohugou, Inner Mongolia, China, have yielded superbly preserved vertebrate fossils. The fossil beds were first misinterpreted as of Early Cretaceous age, based on alleged occurrences of key fossils of the Jehol Biota. Compelling evidence revealed by more rigorous research involving regional biostratigraphy, radiometric dating, and paleontology supports the Middle Jurassic age of the fossil beds. Despite the awesome evidence for the Middle Jurassic age of the Daohugou beds, the age dispute has been resurrected recently by invoking an overturned stratigraphic sequence. A careful review of the data, however, found no evidence that this sequence has been overturned. In addition, many of the assumptions, on which the conjecture of the fossil beds being post‐Middle Jurassic is imprudently based, are self‐contradictory or otherwise misleading. Thus, the post‐Middle Jurassic age of the Daohugou beds as an unfounded conclusion can readily be dismissed

We tested the hypothesis that the high-conductance calciumactivated potassium (K(Ca)) channel is involved in the cardioprotection of preconditioning with ischemic insults. In the isolated perfused rat heart subjected to ischemia/reperfusion, effects of ischemic preconditioning (IPC) on infarct size and lactate dehydrogenase (LDH) release were abolished by 1 muM paxilline (Pax), an inhibitor of the K(Ca) channel, administered 30 min before, but not during, ischemia. In isolated ventricular myocytes subjected to metabolic inhibition and anoxia (MI/A), preconditioning with MI/A increased their viability, and the effect was abolished by administering Pax before MI/A. Like IPC, 10 muM NS1619 (1,3-dihydro-1-[2-hydroxy-5-(trifluoromethyl)phenyl]-5-trifluoromethyl-2Hbenzimidazol-2-one; NS), an opener of K(Ca) channels, reduced infarct size and LDH release, effects attenuated by Pax. The harmful and protective effects of blockade and activation of the K(Ca) channel were accompanied by impaired and improved left ventricular contractile functions, respectively. In addition, the effect of NS was not altered by 100 muM 5-hydroxydecanoate, an inhibitor of the K(ATP) channel. Neither was the effect of 100 muM diazoxide, an activator of the K(ATP) channel, altered by Pax. Furthermore, opening of the mitochondrial permeability transition pore (mPTP) with 20 muM atractyloside abolished the beneficial effects of IPC or NS in the isolated rat heart and myocyte. Inhibition of mPTP opening with 0.2 muM cyclosporin A decreased the infarct size and LDH release and improved the contractile function, effects not attenuated by Pax. In conclusion, the study provides evidence that the K(Ca) channel triggers cardioprotection of IPC, which involves mPTP.

Based on the extended Skyrme force SKa and GS2, the Hartree-Fock and self-consistent semiclassical calculations are carried out to investigate the static properties of 208Pb. The present results are compared with each other and with the experiments. A good agreement is obtained between two theoretical approaches and between theories and experiments.

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