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The monolayer VN as well as multilayer VN/C coatings were obtained on 316 L steel via physical vapor deposition (PVD) technology. Structure, mechanical property and tribo-corrosion behavior of monolayer VN and multilayer VN/C coatings under simulated seawater were estimated by corresponding detection equipment. After analysis, C nanolayer could break the grain growth of VN phase, which would enhance the coating toughness and inhibit the source of crack. At the same time, the multilayer structure interface could suppress the dislocation movement. In tribo-corrosion process, the corrosion current density (icorr) of VN/C coating was 2.71 × 10−6 A/cm2, which was 70.47% lower than that of VN coating (9.18 × 10−6 A/cm2), implying that the nano-multilayer structure of VN/C coating showed a strong barrier effect on corrosion medium. Moreover, the C nanolayer not only suppressed the permeation of simulated seawater, but also formed the transfer film to protect the substrate. Thus, the multilayer VN/C coating revealed stronger anti-wear and anti-corrosion abilities than the monolayer VN coating.

Water Cherenkov detector array (WCDA) is one of the key parts of the Large High Altitude Air Shower Observatory (LHAASO), the construction of which was completed by the end of 2020. The WCDA covers a 78 000-m2 area and there exist 3120 large size photomultiplier tubes (PMTs) in three ponds: 8-in PMTs are used in WCDA pond No. 1 and 20-in PMTs are used in ponds No. 2 and No. 3. The front-end electronics (FEE) system based on multigain measurement technique is designed to achieve both high-precision time and charge measurements over a large dynamic range from single photon electron (S.P.E.) to 4000 P.E. (for water pond No. 1)/1800 P.E. (for water ponds No. 2 and No. 3). To achieve a high-quality clock distribution and phase alignment as well as mixed transmission of data, clock, and commands in one fiber over a long distance, an enhanced white rabbit (WR) technique is used. Testing of all the 350 FEE modules for the WCDA is presented in this article. Test results indicate that the charge resolution is better than 20% at S.P.E. and 1% at 1800/4000 P.E. and the time resolution is better than 300 ps root mean square (rms), which successfully meets the application requirement. All the FEE modules have been fabricated and installed for the LHAASO WCDA from 2018 to 2020, and the initial commissioning operation indicates that the FEEs function well.

The I-mode is a promising operation mode for fusion in the future, featuring high-temperature and low-density confinement, but the reason why the temperature and density are decoupled remains an important aspect to be explored. The experimental results from the experimental advanced superconducting tokamak (EAST) showed that the weakly coherent mode (WCM) is directly related to sustaining the I-mode and that the peak amplitude of the WCM is proportional to the temperature in the pedestal. Simulating the experimental data from EAST with the six-field model of BOUT++, we find a density perturbation close to the frequency of the WCM observed in the experiment. By testing all the physical terms in this model, we find that the density perturbation and particle transport are directly related to the drift Alfvén wave (DAW) mode. We also use the SymPIC program (Xiao et al Plasma Sci. Technol. 20 110501; Phys. Plasmas 22 112504; Plasma Sci. Technol. 23 055102) to simulate the same experimental data and find that the frequency range of the WCM is close to both experimental and BOUT++ results. Therefore, the WCM of the I-mode can be considered to be driven by the DAW, which helps improve the transport of the I-mode.

Polypropylene laminated paper (PPLP) and liquid nitrogen (LN 2 ) is widely used as insulation and coolant, respectively, in high-temperature superconducting (HTS) cable. Dielectric loss of PPLP plays an important role in the loss of HTS transmission system. In this paper, polytetrafluoroethylene (PTFE) filter papers were chosen to take place of Kraft paper (KP) in composite insulation system. Two layers of PTFE filter paper and one layer of polypropylene (PP) film were processed into sandwich structure through hot-press method. Experimental results show that the dielectric loss can be cut to half by replacing KP with PTFE filter in AC HTS transmission system. The trap level of PTFE/PP composite insulation is shallower. The surface discharge voltage of PTFE/PP is higher than that of PPLP. PTFE/PP also has stronger ability of resisting partial discharge and shows higher partial discharge inception voltage than PPLP does. And the breakdown voltage of PTFE/PP composite insulation is higher than that of PPLP, which mainly due to the stronger resistance to discharge.

The failures of polypropylene laminated paper (PPLP), the major insulation of high temperature superconducting (HTS) cables, are mainly rooted in the electrical ageing. In this paper, effects of electrical ageing on AC breakdown and trap distribution characteristics of PPLP are investigated. Electrical ageing under AC voltage of PPLP in liquid nitrogen is carried out. The breakdown performance and trap distribution of PPLP are characterized by AC breakdown and isothermal surface potential decay (ISPD) measurements. In addition, the aged samples are further analyzed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). Results demonstrate that the breakdown strength of PPLP decreases from 113.32 kV/mm to 92.36 kV/mm after ageing for 60 min under 30 kV. The energy level and trap density of deep trap calculated by ISPD results both decrease with ageing. FTIR and SEM indicate that the partial cellulose of insulating paper on the out-layer of PPLP is broken under the impact of high-energy electrons. As a result, the free volume of insulating paper is expanded, and the binding ability of cellulose molecular chains to charge carriers is weakened, which leads to the decrease of energy level and trap density of deep trap and further promotes the charge transportation. Therefore, a decreased breakdown strength of PPLP can be observed after electrical ageing. In conclusion, it is proposed that the destruction of molecular chain structure in the aged PPLP can lead the change of trap distribution, further resulting in the decline of breakdown strength.

Polyimide (PI) film is widely used as insulation material in superconducting magnet systems. While operating, the PI film is subjected to the interaction of electric and magnetic fields. The existence of magnetic field will affect charge behaviors leading to the changes in flashover voltage. In this paper, a steady magnetic field up to 1.2 T was applied to the PI films. The flashover voltages were investigated under DC condition and AC condition. Different angles between magnetic and electric fields were set to explore the influence of magnetic field direction on the flashover voltage of PI film. Experimental results show that the $E\times B$ drifting into the surface will block the secondary electron emission, resulting in an increase in the flashover voltage. When the $E\times B$ drifts out of the surface the result is just the opposite. The promoting effect of magnetic field on the changes of flashover voltage is weakened under the AC condition, while the suppressive effect is strengthened. The failure mechanism of PI film under strong magnetic field will provide a theoretical basis for improving the insulation reliability of superconducting magnets.

The first NSLS-II beamline for infrared and THz spectroscopy recently began operations. The design incorporates features for reaching from the near-UV (~40,000 cm-1) to millimeter waves (~2 cm-1). The high brilliance synchrotron source will be used for a variety of spectroscopic techniques including microspectroscopy, magnetospectroscopy, ellipsometry and materials under extreme pressures and temperatures. Interestingly, the intrinsically short electron bunches (~15 ps rms) results in stable coherent radiation to be observed down to 5 GHz during normal operations.

In this study, the failure modes of cartwheel and mechanical properties of materials have been analyzed. The results show that rim cracking is always initiated from stringer-type alumina cluster and driven by a combination effect of mechanical and thermal load. The strength, toughness, and ductility are mainly determined by the carbon content of wheel steels. The fatigue crack growth resistance is insensitive to composition and microstructure, while the fatigue crack initiation life increases with the decrease of austenite grain size and pearlite colony size. The dynamic fracture toughness, KID, is obviously lower than static fracture toughness, KIC, and has the same trend as KIC. The ratio of KID/sigma YD is the most reasonable parameter to evaluate the fracture resistance of wheel steels with different composition and yield strength. Decreasing carbon content is beneficial to the performance of cartwheel.

The first Water Cherenkov detector of the LHAASO experiment (WCDA-1) has been operating since April 2019. The data for the first year have been analyzed to test its performance by observing the Crab Nebula as a standard candle. The WCDA-1 achieves a sensitivity of 65 mCU per year, with a statistical threshold of 5 . To accomplish this, a 97.7% cosmic-ray background rejection rate around 1 TeV and 99.8% around 6 TeV with an approximate photon acceptance of 50% is achieved after applying an algorithm to separate gamma-induced showers. The angular resolution is measured using the Crab Nebula as a point source to be approximately 0.45° at 1 TeV and better than 0.2° above 6 TeV, with a pointing accuracy better than 0.05°. These values all match the design specifications. The energy resolution is found to be 33% for gamma rays around 6 TeV. The spectral energy distribution of the Crab Nebula in the range from 500 GeV to 15.8 TeV is measured and found to be in agreement with the results from other TeV gamma ray observatories.

This paper investigates the longitudinal and transverse temperature profiles of a strong plume impinging flow, induced by a turbulent porous gas burner impinging on the sidewall confined ceiling of a long-narrow tunnel-like structure. A series of model scale experiments were conducted for fires against a tunnel sidewall with increasing vertical burner heights (0, 0.17 and 0.35 m), 8 different HRRs (heat release rate) from 15.94 to 106.28 kW were used. Measurements of the vertical temperature profiles against the sidewall and radial horizontal temperature profiles under the ceiling are presented. Results show that for the strong impingement plume, the temperatures at the impingement point can be well correlated by the three-regime of buoyant plume, intermittent flame and continuous flame. The horizontal temperature profiles under the ceiling show obviously asymmetric. It is confirmed that the characteristic length scale of plume radius at ceiling level is sufficiently applicable for predicting the ceiling excess temperatures of strong plume impingement flow, and the correlations of the ceiling excess temperature in both transverse and longitudinal directions are proposed and validated by comparing them with previous research.

This paper presents an experimental investigation to explore the effect of tunnel sidewall on flame characteristics and air entrainment factor of methanol pool fires with decreasing distance to the sidewall. Experimental results show that owing to the confinement effect of sidewall, the flame height increases with the decrease of fire-sidewall distance. Especially for fire immediately against sidewall, the air entrainment process is confined to the largest extent and the flame height increases significantly. Correlations of the flame height with difference distances to the sidewall are obtained based on the dimensionless analysis and experimental data. Besides, the Entrainment Factor (EF), which describes the ratio of air entrainment into the confined plume relative to the unconfined one, is estimated for different fire locations. When fire is flush with sidewall, the Entrainment Factor (EF) decreases to 0.46, meaning that only 0.46 times of air is entrained into the flame volume compared to the fire at the longitudinal centerline of tunnel. The flame height and Entrainment Factor under the experimental conditions are also compared to the previous results.

For repairable products sold with two-dimensional warranty, although burn-in and Preventive Maintenance (PM) actions result in extra costs, they both can be effective approaches to reduce number of warranty claims and servicing cost by early detecting defects and reliability improvement. Longer burn-in or higher burn-in usage rate can remove more defects, but it accelerates the product degradation and incurs more wear-out failures, which in turn need to be alleviated by PMs in the warranty period. This article aims to propose a new warranty performance-based model to minimize the warranty claims and find out the optimal burn-in and PM decisions for two-dimensional warranted products. More specifically, the proposed model subsumes a special case under one-dimensional warranty, allows different failure modes—i.e. defects and wear-out failures, and takes usage heterogeneity into consideration. We find that, it is always reasonable to carry out a burn-in on products. If wear-out failures are more (less) sensitive to product usage rate than defects, the burn-in duration should be extended (increased with the upper limit of PM degree); The optimal burn-in usage rate should be increased with the upper limit of PM degree (conducted at conditions as harsh as possible) and decrease with the upper limit of detecting degree; the optimal PM should always be set at its upper limit.

Cysteinyl leukotrienes (CysLTs) induce inflammatory responses by activating their receptors, CysLT1R and CysLT2R. We have reported that CysLT2R is involved in neuronal injury, astrocytosis, and microgliosis, and that intracerebroventricular (i.c.v.) injection of the selective CysLT2R antagonist HAMI 3379 protects against acute brain injury after focal cerebral ischemia in rats. In the present study, we clarified features of the protective effect of intraperitoneally-injected HAMI 3379 in rats. We found that HAMI 3379 attenuated the acute brain injury 24 h after middle cerebral artery occlusion (MCAO) with effective doses of 0.1-0.4 mg/kg and a therapeutic window of ∼1h. It attenuated the neurological deficits, and reduced infarct volume, brain edema, and neuronal loss and degeneration 24 and 72h after MCAO. RNA interference with i.c.v. injection of CysLT2R short hairpin RNA (shRNA) attenuated the acute injury as well. Also, HAMI 3379 inhibited release of the cytokines IL-1β, interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) into the serum and cerebrospinal fluid 24h after MCAO. Moreover, HAMI 3379 ameliorated the microglial activation and neutrophil accumulation in the ischemic regions, but did not affect astrocyte proliferation 72h after MCAO. In comparison, the CysLT1R antagonist pranlukast did not affect microglial activation and IFN-γ release, but inhibited astrocyte proliferation and reduced serum IL-4. Thus, we conclude that HAMI 3379 has a protective effect on acute and subacute ischemic brain injury, and attenuates microglia-related inflammation. CysLT2R antagonist(s) alone or in combination with CysLT1R antagonists may be a novel class of therapeutic agents in the treatment of ischemic stroke.

This study examined sequence variability in internal transcribed spacers (ITS) of nuclear ribosomal DNA among Syphacia obvelata and Aspiculuris tetraptera isolates from laboratory mice from different geographical locations in China. ITS1, 5.8S and ITS2 rDNA were amplified separately from adult S. obvelata and A. tetraptera individuals by polymerase chain reaction (PCR), and the amplicons were subjected to sequencing from both directions. The lengths of the sequences of ITS1, 5.8S and ITS2 rDNA from both nematodes were 314 bp and 456 bp, 157 bp, and 273 bp and 419 bp, respectively. The intraspecific sequence variations in S. obvelata ITS1 were 0–0.3%. For A. tetraptera they were 0–0.7% in ITS1 and 0–1.0% in ITS2. However, the interspecific sequence differences among members of the infraorder Oxyuridomorpha were significantly higher, being 54.0–65.5% for ITS1 and 55.3–64.1% for ITS2. Phylogenetic analysis based on the combined partial sequences of ITS1 and ITS2 using three inference methods – Bayesian inference, maximum likelihood and maximum parsimony – revealed that all the S. obvelata and A. tetraptera samples formed independent monophyletic groups. Syphacia obvelata was closer to Syphacia muris than to A. tetraptera, consistent with morphological classification. These results demonstrate that ITS1 and ITS2 rDNA sequences are useful markers for population genetic studies of oxyurid nematodes.

Summary The tight dolomite gas reservoir found in the Ma 5 member of Daniudi field in Ordos basin in Western China has huge reserves. The main rock physics features of the reservoir includes multi-minerals, complex pores structures, low porosity and permeability, inhomogeneous fluid distribution in the pores. It is difficult to establish a rock physical model that characterizes these features. This paper develops a rock physics model for the tight dolomite reservoir by combine the MPD-KT rock physics model, VRH mean formula, Brie equation and Gassmann equation. This method is used to predict velocities in 67 wells in the study area. The application in actual data proves the validity of the new model.

The prevalence of Clonorchis sinensis infection in freshwater fishes was surveyed in Heilongjiang Province, northeastern China, between August 2011 and September 2013. Thirteen species of freshwater fish (n=3221) and one species of shrimp (n=93) were collected from Songhua river, Nenjiang river and other lakes or ponds in 37 sites of 15 representative cities in Heilongjiang Province. They were individually examined by digestion technique, and the C. sinensis metacercariae were identified morphologically followed by confirmation using sequences of the second internal transcribed spacer of ribosomal DNA. Ten of the 13 examined species of freshwater fishes were infected with C. sinensis metacercariae, while all shrimps were negative. The overall prevalence of C. sinensis infection in 3221 examined freshwater fishes was 19.96%, with 42.57% (272/639) in Pseudorasbora parva, 22.55% (83/368) in Hemicculter leuciclus, 20.44% (121/592) in Carassius auratus, 17.71% (68/384) in Saurogobio dabryi, 10.85% (23/212) in Rhodeus ocellatus, 10.54% (48/455) in Phoxinus lagowskii, 8.20% (21/256) in Perccottus glehnii, 6.25% (5/80) in Misgurnus anguillicaudatus, 4.55% (1/22) in Xenocypris davidi, and 1.49% (1/67) in Cyprinus carpio. The average infection intensity in P. parva was 103.3 encysted metacercariae per gram of fish meat in Zhaoyuan city. The average prevalence of C. sinensis infection in Songhua river, Nenjiang river and lakes or ponds were 31.96% (503/1574), 11.30% (102/903) and 7.93% (59/744), respectively. The prevalence of C. sinensis infection in Zhaoyuan city (43.68%) was the highest among all sampling locations. These results revealed a high-prevalence of C. sinensis infection in freshwater fishes in Heilongjiang Province, northeastern China, posing significant public health concern.

Global warming means that the ability to withstand heat stress is of crucial importance to insects' survival and reproduction. Insects have various ways of achieving thermal tolerance, which can be affected by thermal history, physiological state, and seasonal cycles. In this study, we compared the thermal tolerance of life stages and seasons of a wild population of the striped stem borer, Chilo suppressalis (Walker) (Lepidoptera: Pyralidae), an economically significant pest of rice crops in Asia. Our results demonstrate that the eggs, larvae, and adults of C. suppressalis collected in rice fields in Yangzhou, China, are able to tolerate extremely high temperatures, in excess of those this species encounters in nature. We found that egg masses had a survival rate of 75% after being kept at 42 °C for 8 h. Egg masses exposed to 39 °C for 8 h had the longest hatching time (3.3 days). LTemp₅₀and LTemp₉₀(i.e., the temperatures at which 50 or 90% of individuals died within 2 h) of larvae collected in late summer were 45.4 and 47.3 °C, respectively. LTime₅₀and LTime₉₀(i.e., the time required to kill 50 or 90% of individuals) at 44 °C were 6.2 and 9.6 h, respectively. The corresponding values for 46 °C were 1.5 and 2.6 h. We also found that the heat tolerance of adults collected in late summer was lower than that of larvae. For example, LTemp₅₀of male and female adults was 43.8 and 43.6 °C, respectively. Other measures of the heat tolerance of adults, such as LTime₅₀at 42 °C, also differed between the sexes, being 5.9 h for males and 7.2 h for females. Although adult survival was robust to heat stress, adult fertility was more sensitive. Our results also indicate that although the second generation of adults (i.e., the summer generation) typically encountered higher temperatures than the overwintering generation, survival of the second generation adults was lower.

We obtained a strain of Bacillus subtilis, which we named Czk1, from the aerial roots of rubber trees. This bacterial isolate exhibits strong antagonistic activity against Ganoderma pseudoferreum, Phellinus noxius, Helicobasidium compactum, Rigidoporus lignosus, Sphaerostilbe repens, and Colletotrichum gloeosporioides. Our earlier research has shown that the antagonistic activity of a fermentation supernatant Czk1 isolate produces a complex mixture of lipopeptides. In this study, we used methanol to extract crude lipopeptides, purified them using a Sephadex G-25 column, cloned the lipopeptide genes, and analyzed purified fractions by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) to identify the lipopeptides from B. subtilis strain Czk1. The cloned lipopeptide genes included those that encode the enzymes lpa, ituD, sfp, and fenB. The crude lipopeptides were purified and found in five fractions. Further analysis revealed that five fractions of the purified composition contained members of the surfactin, iturin, fengycin, and bacillomycin families of antibiotics. This suggests that these lipopeptides from strain Czk1 have potential as plant disease biocontrol agents.

To interpret density holes in the solar wind, which are nonlinear structures observed by Cluster and Double Star, we propose an electrostatic ion fluid model. We derive the Sagdeev potential from the magnetohydrodynamic (MHD) equations and study the characteristics of nonlinear structures in our model. The results show that density depletions (or holes) can develop from linear ion acoustic waves or ion cyclotron waves in space plasmas when parameters such as Mach number, initial electric field and ratio of ion to electron temperature satisfy certain conditions. In our model, the relative density depletion (or density holes) is from 0 to 1, and the time duration of density holes is from 2 s to more than 98 s. These are in good agreement with the observations by Cluster and Double Star in the solar wind. Our model also shows that the density holes should be accompanied by bipolar electric field solitary structures, which have also been observed by Cluster in the solar wind.

The objective of the present study was to reveal the characteristics of diacylglycerol O-acyltransferase 1 (DGAT1) gene of high altitude yak ( Bos grunniens ). Two mRNA sequences of yak DGAT1 , including a full length and a spliced isoform deleted with 66 nucleotides in exon VIII, were cloned from Jiulong yak liver by reverse transcription polymerase chain reaction (RT-PCR). The coding sequence (CDS) of yak full length DGAT1 gene is 1470 bp, sharing 99.5% of nucleotide sequence homology and 100% of amino acid sequence homology with those of cattle, respectively. PCR analysis using DNA and RNA as templates demonstrated the alternative splicing of yak DGAT1 gene and estimated the proportion of the spliced isoform as approximately 30% of the total DGAT1 mRNA in yak liver and biceps femoris. Quantitative real-time RT-PCR analysis showed that both adult yak and cattle had significantly higher DGAT1 mRNA level in liver and adipose tissue than in skeletal muscles ( P 0 . 05 ), while no difference was observed between the corresponding tissues of yak and cattle, suggesting that yak DGAT1 gene might not be responsible for the lower intramuscular fat content in yaks compared to cattle. Allelic variation at nucleotide positions 10433 and 10434 (K232A) of the DGAT1 gene of yak and cattle was detected by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method. Nearly all yaks (n = 81) examined were homozygous for the K allele, while Chinese Holstein cows showed high frequency for the A allele. The K allele of yak DGAT1 gene might be correlated with its higher milk fat content characteristic.

To meet the growing demands of the global photovoltaic (PV) industry, preparing large scale and ultra-thin solar wafers becomes one of the key issues. This paper presents the preparatory investigations of slicing solar silicon ingot into wafers by an abrasive electrochemical method based on a multi-wire saw system. The anodic passivation on silicon can be controlled by applying an anodic potential during the mechanical slicing process, which improves the surface integrity and material removal rate remarkably. This new hybrid machining method has no influence on subsequent cleaning of wafers and preparing the solar cells, and the average photoelectric transformation efficiency is >17.5%.

Efficient and compact blue laser output at 468 nm is generated by intracavity frequency doubling of a continuous-wave (CW) diode-pumped Nd:CNGG laser at 935 nm. With 17.8 W of diode pump power and the frequency-doubling crystal BiB3O6 (BiBO), a maximum output power of 490 mW in the blue spectral range at 468 nm has been achieved, corresponding to an optical-to-optical conversion efficiency of 2.8%; the output power stability over 4 h is better than 2.6%. To the best of our knowledge, this is first work on intracavity frequency doubling of a diode pumped Nd:CNGG laser at 935 nm.

This paper will discuss the design and construction of BESIII, which is designed to study physics in the tau-charm energy region utilizing the new high luminosity BEPCII double ring e+e- collider. The expected performance will be given based on Monte Carlo simulations and results of cosmic ray and beam tests. In BESIII, tracking and momentum measurements for charged particles are made by a cylindrical multilayer drift chamber in a 1 T superconducting solenoid. Charged particles are identified with a time-of-flight system based on plastic scintillators in conjunction with dE/dx (energy loss per unit pathlength) measurements in the drift chamber. Energies of electromagnetic showers are measured by a CsI(Tl) crystal calorimeter located inside the solenoid magnet. Muons are identified by arrays of resistive plate chambers in the steel magnetic flux return. The level 1 trigger system, Data Acquisition system and the event filter system based on networked computers will also be described., 57 pages, 75 figures

As the semiconductor industry requires the cutting of silicon ingots into wafers, the slicing of large, ultra thin wafers is one of the main technologies to prevent wastage. Recently, apart from conventional inner diameter (ID) blade and multi-wire saw methods, wire electrical discharge machining (WEDM), which has no cutting force, has been introduced to this area and low resistance silicon may be sliced by WEDM. In this paper, a novel approach, based on wire electrolytic-spark slicing strategy using hybrid oil/aqueous electrolyte, combining electric discharge and anodic etching into a single process, is investigated experimentally. Some improvements, such as a new wire winding system, hybrid electrolyte and high efficiency pulse generator, have been adopted in a kind of high speed (HS)-WEDM machine. Experiments have been conducted to evaluate the machining rate, surface quality and wafer thickness of low resistance (0.5–3 Ω cm) mono-crystalline silicon. It has been demonstrated that with properly selected electrical parameters and electrolyte, a maximum machining rate of 600 mm2/min can be obtained and with a wafer thickness less than 120 μm. Furthermore, in comparison with WEDM, heat affected zone and harmful metal residues are considerably diminished, which provides significant theoretical and experimental support for future applications.

The aim of the study was to investigate the effect of duration of dietary linseed feeding on subcutaneous fat, intramuscular fat depot and muscle mass of growing–finishing barrows. Two isoenergetic and isonitrogenous diets were formulated, and one of which was the basal diet and another one was the linseed diet including linseed at the level of 10%. Twenty-four Landrace × Yorkshire barrows weighing 35 ± 3.7 kg were randomly assigned to four treatments with six replications per treatment. Pigs in treatment 1 (T1) fed the control diet throughout the experimental period, while pigs in T2, T3, and T4 fed the control diet except for 30, 60, and 90 d prior to slaughter when the linseed diet were fed. The experiment was conducted for 90 d. Carcass quality and meat quality data were collected and analyzed. The longissimus muscle mass, posas minor mass and each muscle mass in the hind leg were weighted. Additionally, fatty acid composition (%) of the diet, the longissimus dorsi muscle and the backfat were analyzed by gas chromatography method. No significant difference (P > 0.05) was observed for average backfat thickness, lean meat percentage, loin muscle area, whereas the intramuscular fat content increased linearly (P

Refuge selection and byssus production as anti-predator responses were examined in mussels Brachidontes variabilis exposed to cues either released from damaged or intact conspecifics, from damaged or intact heterospecific mussels Perna viridis sympatric with B. variabilis or from shrimp meat as novel cues. Most of the mussels from all treatment groups would seek and stay in a refuge for the first few hours, with a significantly higher number of mussels from the damaged conspecific group seeking refuge. More mussels preferred a smaller refuge when they were exposed to conspecific or heterospecific cues; mussels from other treatments did not select particular sizes of refuge. Damaged conspecific and heterospecific cues elicited the greatest responses in byssus production with more byssal threads being produced, which were also longer and thicker. Novel cues elicited medium levels of response, suggesting that some common cues from injured or dead individuals from different taxa were released, which induced anti-predator responses in B. variabilis.

Using data collected with the BESII detector at Beijing Electron-Positron Collider, the measurements of relative branchin- fractions for seven Cabibbo-suppressed hadronic weak decays D-0 -> K-K+, pi-pi(+), pi(-)pi(+)pi(-) and pi-pi(+)pi(-), D-divided by -> (K) over bar K-0(divided by), K-K+pi(+) and pi(-),pi(+pi+) are presented. (c) 2005 Elsevier B.V. All rights reserved.

The decay psi' + pi(+)pi(-)pi(0) is analyzed using a sample of 14 million psi' events taken with the BESII detector at the BEPC, and the branching fraction is measured to be B(psi' -> pi(+)pi(-)pi(0)) = (18.1 +/- 1.8 +/- 1.9) x 10(-5). A partial wave analysis is carried out using the helicity amplitude method. psi' -> rho(770)pi is observed, and the branching fraction is measured to be B(psi' -> rho(770)pi) = (5.1 +/- 0.7 +/- 1.1) x 10(-5), where the first error is statistical and the second one is systematic. A high mass enhancement with mass around 2.15 GeV/c(2) is also observed. Attributing this enhancement to the p(2150) resonance, the branching fraction is measured to be B(psi' -> rho(2150)pi -> pi(+)pi(-)pi(0)) = (19.4 +/- 2.5(-3.4)(+11.5)) x 10(-5). The results will help in the understanding of the longstanding "rho pi puzzle" between J/psi and psi' hadronic decays. (c) 2005 Elsevier B.V. All rights reserved.

A partial wave analysis is presented of J/psi --> phipi(+)pi(-) and phiK(+)K(-) from a sample of 58M J/psi events in the BES II detector. The f(0)(980) is observed clearly in both sets of data, and parameters of the Flatte formula are determined accurately: M = 965 +/- 8(stat) +/- 6(syst) MeV/c(2), g(1) = 165 +/- 10 +/- 15 MeV/c(2), g(2)/g(1) = 4.21 +/- 0.25 +/- 0.21. The phipipi data also exhibit a strong pipi peak centred at M = 1335 MeV/c(2). It may be fitted with f(2)(1270) and a dominant 0(+) signal made from f(0)(1370) interfering with a smaller f(0)(1500) component. There is evidence that the f(0)(1370) signal is resonant, from interference with f(2)(1270). There is also a state in pipi with M = 1790(-30)(+40) MeV/c(2) and Gamma = 270(-30)(+60) MeV/c(2); spin 0 is preferred over spin 2. This state, f(0)(1790), is distinct from f(0)(1710). The phiK (K) over bar data contain a strong peak due to f(2)'(1525). A shoulder on its upper side may be fitted by interference between f(0)(1500) and f(0)(1710). (C) 2004 Elsevier B.V. All rights reserved.

New data are presented on J/psi --> omegaK(+)K(-) from a sample of 58M J/psi events in the upgraded BES II detector at the BEPC. There is a conspicuous signal for f(0)(1710) --> K+K- and a peak at higher mass which may be fitted with f(2)(2150) --> K (K) over bar. From a combined analysis with omegapi(+)pi(-) data, the branching ratio BR(f(0)(1710) --> pipi)/BR(f(0)(1710) --> K (K) over bar) is < 0.11 at the 95% confidence level. (C) 2004 Elsevier B.V. All rights reserved.

The cross sections for D 0 D ¯ 0 and D + D − production at 3.773 GeV have been measured with BES-II detector at BEPC. These measurements are made by analyzing a data sample of about 17.3 pb −1 collected at the center-of-mass energy of 3.773 GeV. Observed cross sections for the charm pair production are radiatively corrected to obtain the tree level cross section for D D ¯ production. A measurement of the total tree level hadronic cross section is obtained from the tree level D D ¯ cross section and an extrapolation of the R u d s below the open charm threshold.

Using a sample of 58 million J/psi events recorded in the BESII detector, the decay J/psi --> omegapi(+)pi(-) is studied. There are conspicuous omegaf(2)(1270) and b(1)(1235)pi signals. At low pipi mass, a large, broad peak due to the sigma is observed, and its pole position is determined to be (541 +/- 39) - i (252 +/- 42) MeV from the mean of six analyses. The errors, which are dominated by the systematic errors, cover the statistical and systematic errors in the six analyses, as well as the observed variation of the six analyses. (C) 2004 Elsevier B.V. All rights reserved.

To place β-FeSi 2 as a 3rd generation Kankyo (Environmentally Friendly) Semiconductor after GaAs, one should demonstrate its superior features by fabricating practical devices. One has to prepare high-quality β-FeSi 2 films with (1) precisely controlled Fe/Si ratio (1:2), (2) flat and cracks-free surface, (3) pinhole-free surface and interfaces, (4) flat interfaces, (5) well-controlled electron or hole concentration with residual carrier concentration as low as ∼10 16 cm −3 . One should accordingly explore novel thin film manufacturing technologies by considering specific properties of constituent Fe and Si atoms. Conventional growth methods used for III–V and II–VI compound semiconductor films are not suited for β-FeSi 2 . Here we summarize the current status of film preparation technologies and describe their advantages and drawbacks. To explore the possibility of β-FeSi 2 for low cost and high conversion efficiency solar cells, high quality β-FeSi 2 films have been formed on Si substrates by molecular beam epitaxy (MBE) and sputtering methods. The critical feature about the device structure is an optimized thin β-FeSi 2 template buffer layer on Si(111) substrate. The template served as a substrate for epitaxial growth of single crystal β-FeSi 2 film and restrains the Fe diffusion into Si at β-FeSi 2 /Si interface. For n-β-FeSi 2 /p-Si structure under air mass 1.5, an energy conversion efficiency of 3.7% was obtained, showing that β-FeSi 2 is practically a promising semiconductor for making solar cells.

Using a sample of 58×10 6 J / ψ events collected with the BESII detector, radiative decays J / ψ → γγV , where V = ρ or φ , are studied. A resonance around 1420 MeV/ c 2 ( X (1424)) is observed in the γρ mass spectrum. Its mass and width are measured to be 1424±10(stat)±11(sys) MeV/ c 2 and 101.0±8.8±8.8 MeV/ c 2 , respectively, and its branching ratio B ( J / ψ → γX (1424)→ γγρ ) is determined to be (1.07±0.17±0.11)×10 −4 . A search for X (1424)→ γφ yields a 95% C.L. upper limit B ( J / ψ → γX (1424)→ γγφ ) −4 .

Using a sample of 5.8X10E7 J/$\psi$ events, the Beijing Spectrometer experiment has searched for the decay J/$\psi \to e\mu$. Four candidates, consistent with the estimated background, are observed, and an upper limit on the branching fraction of J/$\psi \to e\mu$ of 1.1X10E-6 at the 90% C.L. is obtained.

The structural, magnetic and transport properties of the compounds Sr2(Fe1−xMnx)MoO6 (0 ≤ x ≤ 0.45) have been studied. The saturated magnetization, Curie temperature and low-field magnetoresistance of the compounds decrease with x, while the resistivity increases by several orders of magnitude when x exceeds a critical value. A positive magnetoresistance has been observed for x = 0.45. A possible percolation mechanism is proposed to elucidate the observations; it also suggests a coexistence of (Mn3+, Mo5+) and (Mn2+, Mo6+) valence pairs and a saturated substitution of Mn3+ for Fe3+.

Polycrystalline MgB2 with a sharp superconducting transition at 39 K was directly synthesized from the elements using high pressure. The sample showed high critical current densities. The electron energy-loss spectrum of B shows the peaks of σ and antibonding bonds, in good agreement with the hole-doping theoretical calculations. The pressure dependences of the sound velocities were measured up to 0.5 GPa, and subsequently elastic moduli, the Debye temperature and the specific heat were calculated. The isothermal Murnaghan equation of state of MgB2 is established. Also, the pressure coefficient of the phonon frequency and the volume dependence of the electron–phonon coupling constant are calculated.

C3N4H4 was treated at 6.0 GPa and 1500 °C for 2.5 min. Powder x-ray measurement shows that the sample is decomposed and a hexagonal graphite phase forms. Transmission electron microscopy studies show that small amounts of diamond and amorphous carbon phase coexist with the graphite phase. Parallel electron energy-loss spectroscopy analysis was also carried out for these phases.