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Since Sep. 2018, LAMOST started the medium-resolution (R $\sim 7500$) spectral survey (MRS). We proposed the spectral survey of Galactic nebulae, including \hii\ regions, HH objects, supernova remnants, planetary nebulae and the special stars with MRS (LAMOST MRS-N). LAMOST MRS-N covers about 1700 square degrees of the northern Galactic plane within $40^\circ < l < 215^\circ$ and $-5^\circ < b < 5^\circ$. In this 5-year survey, we plan to observe about 500 thousand nebulae spectra. According to the commissioning observations, the nebulae spectra can provide precise radial velocity with uncertainty less than 1 km s$^{-1}$. These high-precision spectral data are of great significance to our understanding of star formation and evolution., Submitted to RAA. 13 pages, 7 figures, 1 table

The LAMOST II survey began in the fall of 2018, and LAMOST formally released the obtained medium-resolution spectra (MRS) as well as catalogs of stellar parameters and radial velocities (RV) derived from the MRS in the seventh LAMOST data release (DR7). Compared with the RVs and parameters from high-resolution SDSS14/APOGEE spectra, nearly no RV discrepancy was found, with only dispersion around one km s−1. The T eff of MRS was 27.79 K systematically lower than that of APOGEE, and the 1σ difference was approximately 60.40 K. For metallicity, the [Fe/H] of the MRS was 0.11 dex poorer than that of APOGEE, with a dispersion of 0.07 dex. More apparently, the offset of log g was 0.14 dex, and the scatter was 0.23 dex. The gravities of APOGEE have been corrected through seismological data. Similarly, in this study, we tried to calibrate LAMOST MRS log g with the Kepler data for red clump stars and red giant branch stars based on two fitted calibration relations. In addition, we found log g of a small fraction late-K type giants mistakenly measured as dwarfs, and vice versa, on the HR diagram generated with LAMOST T eff and Gaia absolute magnitudes. This was because the MRS parameters were measured from blue band spectra only. The measurements of log g for late-K stars can be significantly improved by adding red spectra.

Applying the revised M subdwarf classification criteria discussed in Paper I to LAMOST DR7, combining the M subdwarf sample from Savcheva et al, a new M subdwarf sample was constructed for further study. The atmospheric parameters for each object were derived fitting with the PHOENIX grid, combining with Gaia DR2, the relationship between the gravity and metallicity were explored according to the locus both in the color-absolute magnitude diagram and the reduced proper motion diagram. Objects that have both the largest gravity and the lowest metallicity are located away from the main-sequence cloud and may be considered as the intrinsic M subdwarfs, which can be classified as luminosity class VI. Another group of objects whose spectra show typical M subdwarf characters have lower gravity and relatively moderate metal deficiency and occupy part of the ordinary M dwarf region in both diagrams. The Galactic U , V , W space velocity components and their dispersion show that the local Galactic halo population sampled in the solar neighborhood is represented by objects of high gravity and an inconspicuous bimodal metallicity distribution, with a fraction of prograde orbits. The other M subdwarfs seem to partly belong to the thick disk component with a significant fraction of thin disk moderately metal-poor objects intricately mixed with them. However, the selection effects, especially the favored anti-center direction of investigation in the LAMOST sub-sample, but also contamination by multiplicity and parameter coupling could play important roles and need to be further investigated., 22 page, 19 Figures, Accepted by ApJ

Based on the spin-flip model, the polarization switching (PS) characteristics of two polarization outputs in a 1550-nm vertical-cavity surface-emitting laser (1550-nm VCSEL) subject to double polarization pulsed injection (DPPI) are investigated theoretically, and the obtained results are compared with the case, in which the 1550-nm VCSEL is simultaneously injected by the pulses of orthogonal polarized light and a continuous wave (CW) parallel polarized light, which is called double optical injection with pulsed orthogonal polarization (DIPOP). The simulated results show that, compared with the DIPOP, the DPPI method is beneficial to improving the PS performance under suitable parameters. The influences of the timing difference (Δt) in the switching of two injection pulses on the PS performance of 1550-nm VCSEL subject to DPPI are analyzed, and the optimized values of At under different bias currents are determined. Furthermore, for optimized At, the dependences of the switching times on the amplitudes of two polarization pulses and the frequency detuning are given.

The present study, which is based on the finite element method, investigates the alloy element content assessment of these Fe-Si alloy steel sheets from the view point of eddy current testing. The relative permeability and conductivity were preset parameters. Eddy current signals were gathered by a differential type cylindrical probe and subsequent nondestructive tests were carried out with the preparation of four Fe-Si alloy steel sheets with different silicon contents. The result of the numerical simulation demonstrated that the signal increased with the increase of the silicon content in the Si-Fe alloy steel sheets. And the measured result confirmed the rationality of the application of eddy current testing in the average silicon content assessment.

Two new highly oxygenated guaiane-type sesquiterpenoids (1 and 2), along with nine known compounds (3–11) were isolated from the methanol extract of Senecio densiserratus Chang by cytotoxicity-guidance. Their structures were elucidated through spectroscopic analysis (IR, HRESIMS, 1D and 2D NMR) as well as by comparison with literature data. The two new compounds represent a rare type of guaiane sesquiterpenoid glucosides with angeloyloxy groups directly connected to the glycosyl moiety. Compounds 1–3, 8 and 10 displayed broad-spectrum inhibitory activity against the human leukemia cell (HL-60), human hepatoma cell (SMMC-7721) and human cervical carcinoma cell (HeLa), with IC50 values ranging from 9.5 to 28.3 μM in vitro. The new compounds also displayed moderate activity against plant pathogenic fungi of Penicillium italicum and Rhizoctonia solani with IC50 values from 19.4 to 33.1 μM.

Two new 29-nor-cycloartane triterpenes, amooratsanols A and B (1, 2) along with nine known compounds including two 29-nor-cycloartane triterpenes (3, 9), two lupane triterpenes (4, 5), two cycloartane triterpenes (6, 10), two dammarane triterpenes (7, 8), as well as one dinorcycloartane triterpene (11) were isolated from the leaves and twigs of Amoora tsangii (Merr.) X. M. Their structures were established by spectroscopic methods (IR, HRESIMS, and NMR). The cytotoxicity of 1-11 was evaluated against the human fibro sarcoma HT1080, esophageal cancer TE, and non-small cell lung cancer A549 cell lines by the CCK8 assay. Cycloartanes (1-3, 6, and 9-11) displayed significant cytotoxic activity with IC50 values ranging from 2.56 to 19.05 mu M. Among these triterpenes, mooratsanol A (1) showed the most potent cytotoxic activity, with IC50 values ranging from 2.56 to 5.10 mu M. (C) 2016 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.

Edge cracks are commonly observed in steel strip in cold rolling, which may cause deterioration of quality and productivity of products. The edge defect is one of the important factors that lead to edge cracks in cold rolling. In this paper, the GTN damage model coupled with shear damage mechanism proposed by Nahshon and Hutchinson (2008) was employed to analyze the ductile damage and failure behavior of steel sheet with edge defects under multi-pass cold rolling. Cold rolling experiments of silicon steel with edge notches were performed on an experimental rolling mill to verify the accuracy of the numerical results. The simulation results show that two cracks appeared in the notch tip after five passes rolling and extended toward the direction with an angle around 45° and 135° to the rolling direction, which was in good agreement with the experimental data. The influences of notch shape and size on the onset of cracks around the notch tip are investigated and some significant conclusions are drawn.

Narrowband and high-transmission optical filters are extensively used in color display technology, optical information processing, and high-sensitive sensing. Because of large ohmic losses in metallic nanostructures, metallic filters usually exhibit low transmittances and broad bandwidths. By employing both strong field enhancements in metallic nano-slits and the Wood’s anomaly in a periodic metallic grating, an extra-narrowband and high-transmission metallic filter is numerically predicted in an ultrathin single-layer metallic grating. Simulation results show that the Wood’s anomaly in the ultrathin (thickness H = 60 nm) single-layer metallic grating results in large field enhancements in the substrate and low losses in the metallic grating. As a result, the transmission bandwidth (transmittance T > 60%) at λ = 1200 nm is as small as Δλ FWHM = 1.6 nm, which is smaller than 4% of that in the previous thin dielectric and metallic filters. The corresponding quality factor is as high as Q = λ/Δλ FWHM = 750, which is 40 times greater than that in the previous reports. Moreover, the thickness of our metallic filter (H = 60 nm) is smaller than 40% of that in the previous reports, and its maximum transmittance can reach up to 80%. In experiments, a narrowband metallic filter with a bandwidth of about Δλ FWHM = 10 nm, which is smaller than 25% of that in the previous metallic filters, is demonstrated.

Three new 2,4-dinitrobenzenesulfonyl derivatives 1–3 were successfully prepared for the first time using a simple process. They were efficiently triggered by thiols (glutathione and l -cysteine) to release the corresponding phenol derivatives (4–6) within 5 min. The quick response of 1–3 toward thiols was determined by 1H NMR and HPLC. Moreover, our results indicated that 1 could induce DNA cross-linking in the presence of glutathione, probably due to the quinone methide formation of phenol intermediate 4 followed by departure of 2,4-dinitrobenzenesulfonyl group.

2¼Cr-1Mo-¼V steel is used for manufacturing and producing hydrogenation reactors. The coarse-grained heat affected zone (CGHAZ) of welded joints using 2¼Cr-1Mo-¼V steel have a higher reheat cracking susceptibility than the conventional 2¼Cr-1Mo steel. But there is no simple and effective method evaluating reheat cracking susceptibility of CGHAZ in 2¼Cr-1Mo-¼V steel welded joints at present. Based on Weld C-Ring Test and Gleeble® Thermo-Mechanical Test, a new Notched C-Ring Test to evaluate reheat cracking susceptibility of CGHAZ in 2¼Cr-1Mo-¼V steel was studied in this paper. According to the fitting relationship between RoA and critical stress, a criteria was proposed preliminarily to determine the reheat cracking susceptibility of 2¼Cr-1Mo-¼V steel CGHAZ using “not susceptible” and “slightly susceptible”.

Transforming growth factor β-stimulated clone 22 domain 1 (TSC22) has been identified as a cancer suppressor gene in various kinds of cancers. The purpose of this study was to explore the expression of TSC22 in colorectal cancer (CRC) tissues and cell lines. 24 matched CRC and normal tissue samples by qPCR along with 18 pairs of them by Western blot demonstrated TSC22 level was decreased in CRC compared with normal tissue. The protein expression of TSC22 was examined in 310 CRC specimens. Results showed low expression of TSC22 was significantly correlated with tumor size (P = 0.048) and tumor infiltration (P = 0.016). Kaplan-Meier method suggested low expression of TSC22 was inversely associated with OS for 276 samples (P

The winter and summer microbial community structure in sediment samples obtained from the estuaries of the wastewater-polluted River Ou (DO and XO), River Feiyun (DF and XF), and River Ao (DA and XA) in the south of Zhejiang Province in China was determined using 454 pyrosequencing. Sediment samples (DD and XD) were also correspondingly collected near the shore far from the estuaries for comparison. For the above sediments, 294,870 effective sequences were obtained to do the bacterial diversity and abundance determination. In total, 1924, 1517, 2071, 1956, 1995, 1800, 2261, and 2097 operational taxonomic units were obtained at 3 % distance cutoff in the DO, XO, DF, XF, DA, XA, DD, and XD sediments, respectively. Bacterial phylotype richness in DD was higher than the other sediments, and XO had the least richness. The most dominant class in the DA, DD, DF, DO, and XA sediments is Gammaproteobacteria. Deltaproteobacteria is the most dominant one in XD, XO, and XF. Circa 14.4 % sequences in XD were found to be affiliated with the Flavobacteriales order. Characterization of the estuarine sediment bacterial communities indicated that chemical pollution has the potential to decrease the natural variability that exists among estuary ecosystems. However, chemical pollutants did not cause clear bio-homogenization in these estuaries.

We present a spectroscopic catalog of 93 619 M dwarfs from the first data release of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) general survey. During sample selection, M giant contamination was eliminated using 2MASS photometry and CaH/TiO molecular indices. For each spectrum, the spectral subtype and values are provided including radial velocity, Hα equivalent width, a series of prominent molecular band indices, and the metal–sensitive parameter ζ, as well as distances and the space motions for high S/N objects. In addition, Hα emission lines are measured to examine the magnetic activity properties of M dwarfs and 7179 active ones are found. In particular, a subsample with significant variation in magnetic activity is revealed through observations from different epochs. Finally, statistical analysis for this sample is performed, including the metallicity classification, the distribution of molecular band indices and their errors.

A sequential extraction approach was used to evaluate the effects of various combinations of passivators (sepiolite, phosphate rock, and coal fly ash) on the concentration and speciation of Cu in swine manure aerobic compost along with soil to which the compost had been applied. The results indicate that the various passivators altered the bound forms of Cu in pig manure and soil; the concentrations of exchangeable and Fe-Mn-bound Cu decreased, whereas the residual Cu concentration increased, indicating that Cu transformed to low-availability forms after the passivator treatments. The concentrations of the carbonate-bound and organic-bound Cu varied widely. Among all treatments, the treatment of the control + straw + sepiolite + coal fly ash (2.5 %) + phosphate rock (5.0 %) resulted in the most efficient passivation of Cu; the percentage of residual Cu reached 3.91-21.14 %, obviously surpassing the percentage for the control without passivation. The treatment of the control + straw + sepiolite + phosphate rock (2.5 %) resulted in the lowest residual Cu fraction (0.85 %) among passivator treatments. These results show that the addition of suitable combinations of passivators to the composting process reduced the availability of Cu and the risk of Cu pollution during the application of composted pig manure to soil. Passivation also decreased the Cu content of Apium graveolens.

Medicinal plants are popular and widely used as a major source of herbal drugs and pharmaceutical compounds. Ever-growing demands make medicinal plants faced to several problems including efficacy and safety to meet business requirements, conservation, and artificially assisted breeding. As a powerful molecular tool, microsatellites offer the great potentials for various purposes in plants. This review provides a scenario of microsatellites in medicinal plants including development from genomic or expressed sequence tag libraries, cross-species transferability, genotyping, and potential applications. We emphasized on the authentication of medicinal plants by microsatellite markers.

Edge cracking is a commonly observed phenomenon in cold rolling process, but researchers appear to be far from fully understanding its failure mechanism due to the complex stress conditions of steel strip under the rolling condition. In this research, the shear modified GTN damage model coupled with Nahshon-Hutchinson shear damage mechanism was applied to investigate the damage and fracture behavior of steel strip in cold rolling. The results show that the shear modified GTN damage model is competent to predict the damage and fracture behavior of steel strip in cold rolling. By comparison to the cold rolling experiment, it presents that the prediction of edge crack occurrence of the shear modified GTN damage model is more accurate than that of the original GTN damage model.

Several novel series of sesquiterpene mustards (SMs) bearing nitrogen mustard and glutathione (GSH)-reactive α-methylene-γ-butyrolactone groups were successfully prepared for the first time and showed excellent antiproliferative activities in vitro. Among them, compounds 2e and 2g displayed the highest antiproliferative properties with IC50 values ranging from 2.5 to 8.7 μM. The selectivity of these two compounds was evaluated by SRB method against human cancer and normal hepatic cells (HepG2 and L02). The induction of apoptosis and effects on the cell cycle distribution with compounds 2e and 2g were investigated by Hoechst 33,258 staining and flow cytometry, which exhibited that they could induce selective cell apoptosis and cell cycle arrest in HepG2 and L02 cells. In addition, further investigation showed that compounds 2e and 2g could obviously inhibit the proliferation of HepG2 cells by inducing significant DNA cross-linking and depleting GSH in cell media. The good cytotoxicity and selectivity of compounds 2e and 2g pointed them as promising leads for anticancer drug design.

To characterize blood glucose fluctuation during hemodialysis in patients with end stage diabetic nephropathy (ESDN) by a continuous glucose monitoring system (CGMS), and aim to improve blood glucose control in this patient population.Forty-six patients with or without type 2 diabetes mellitus (T2DM), receiving hemodialysis, were recruited in this study. Thirty-six patients had end stage diabetic nephropathy (ESDN group), the other ten patients had end stage renal disease without diabetes (ESRD group). A continuous glucose monitoring system (CGMS) was employed to monitor glycemic fluctuation for 72 hours. Blood samples were collected and analyzed.Mean, standard deviation (SD), maximum, and mean amplitude glycemic excursion (MAGE) of blood glucose and the ratio of blood glucose readings that was greater than 13.9 mmol/L of ESDN group, were significantly greater than those of ESRD group (p0.01 for all) during 72 hours of observation. The mean blood glucose was significantly lower, while SD and MAGE were significantly higher in ESDN group on hemodialysis day than on days off hemodialysis (p0.05), while these were not been observed in ESRD group. Though mean, SD, and MAGE of blood glucose during hemodialysis were significantly lower than those of peri-hemodialysis in both groups (p0.01 or p0.05, respectively), they were significantly higher in ESDN group than that in ESRD group (p0.05). The mean blood glucose value calculated from HbA1c did not reflect the actual mean blood glucose measured by CGM in both groups, and gave an inaccurate impression of a significantly lower mean glucose.ESDN patients had larger glycemic fluctuations as compared with ESRD patients. Hemodialysis caused reduction in mean, SD, and MAGE, which in turn caused bigger glycemic fluctuations on hemodialysis day. The HbA1c in ESDN patients gave an inaccurate value, which did not truly reflect blood glucose status for a prolonged period.

Vanadium-sol modified LiFePO4 material was prepared by 300 °C calcination in a tube furnace. The modified LiFePO4 material was characterized by X-ray diffraction, field emission scanning electron microscopy, energy disperse spectroscopy and electrochemical impedance spectroscopy. The results indicated that vanadium-sol modified LiFePO4 had higher first cycling efficiency, lower impedance and polarization, and better electrochemical properties at high charge/discharge rates.

We have proposed and experimentally demonstrated a novel approach to stabilize the photonic microwave generated by the period-one (P1) nonlinear dynamics of an optically injected semiconductor laser by introducing external subharmonic microwave modulation technique. External optical injection first drives a semiconductor laser into single sideband (SSB) P1 nonlinear dynamics whose frequency can be tuned by varying the optical injection strength, and then an external subharmonic microwave modulation is applied to the laser for stabilizing the frequency of the P1 oscillation. The experimental results show that after adopting 1/3 and 1/4 subharmonic microwave modulation, significant reduction up to more than three orders of magnitude of generated microwave linewidth can be achieved. Furthermore, we have analyzed the linewidth narrowing effects under subharmonic modulation with different powers and frequencies, and mapped the subharmonic microwave locking region in the parameter space of the power and frequency of the external subharmonic microwave.

In screening for acetylcholinesterase (AChE) inhibitors and cytotoxic constituents from medicinal plants, a bioactivity-guided isolation of the alkaloidal extract of the whole plant of Palhinhaea cernua led to the isolation of six lycopodium alkaloids. Their structures were elucidated by spectroscopic methods (IR, MS and NMR). The absolute configuration of 1 was established by computational methods. To our best knowledge, compound 1 was a rare cernuane-type alkaloid bearing an oxygen bridge between C-12 and C-15 in Lycopodiaceae. Among these alkaloids, compound 5 was the most active against AChE with IC50 value of 1.9 mu M, and the new compound 1 showed weak inhibitory activity with IC50 value of 102 mu M. Moreover, the new compound 1 and the known one 3 inhibited A549 cell line with IC50 values of 12.6 and 18.4 mu M, respectively. Meanwhile, preliminary structure-activity relationships were discussed in this study. (C) 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.

A new anthraquinone-fused enediyne, yangpumicin A (YPM A, 1), along with four Bergman cyclization congeners (YPM B-E, 2-5), was isolated from Micromonospora yangpuensis DSM 45577 after mining enediyne biosynthetic gene clusters from public actinobacterial genome databases and prioritizing the hits by an enediyne genome neighborhood network analysis for discovery. YPM A is potent against a broad spectrum of human cancer cell lines. The discovery of 1 provides new opportunities for the functionalization of enediynes to develop new conjugation chemistries for antibody-drug conjugates.

The effects of acid concentration, temperature and the thickness of strip oxide scale on the pickling time of high strength steel were studied and a pickling time mode was established. The end time of acid pickling was determined by introducing the electropotetial derivative near zero method. The effects of different pickling temperatures and acid concentrations on the pickling time of different thickness scales were studied by further experiments. When increase acid concentration to 10%, pickling time is greatly reduced, and continue to increase the acid concentration will have little help to shorten the pickling time. When the acid temperature reaches 80 ℃, the pickling efficiency reaches the highest value. If the temperature continuous to increase, it will not only waste energy but also increases the volatilization of hydrochloric acid. The comprehensive pickling model was established and the actual high strength steel pickling data was brought into the test. The proposed comprehensive pickling model in this paper has better accuracy and validity than the old ones.

Two unusual normonoterpenoid indole alkaloids rauvomine A (1) and rauvomine B (2), together with two known compounds peraksine (3) and alstoyunine A (4), were isolated from the aerial parts of Rauvolfia vomitoria. The structures with absolute configurations of 1 and 2 were elucidated by spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism (ECD) calculations. Compound 2 is a novel C18 normonoterpenoid indole alkaloid with a substituted cyclopropane ring that forms an unusual 6/5/6/6/3/5 hexcyclic rearranged ring system. The plausible biogenetic pathways of 1 and 2 were proposed. Compound 2 exhibited significant anti-inflammatory activity.

Elymus natans, a perennial gramineous grass, plays an important role in animal husbandry and environmental sustenance in the Qinghai–Tibet plateau as a result of its high forage quality and good adaptability to the local environment. A bioassay showed that the extracts of green grasses of E. natans (GG) exhibited stronger phytotoxic activities than withered grasses (WG) against crops and grasses. In view of the secondary metabolites, which may be responsible for the resistance of the plant, the chemical components of GG were investigated. The flavone tricin, E1, and 10 flavonolignans, E2–E11, including three new flavonolignans, E2, E10, and E11, were isolated and identified. As far as we know, this is the first report on the chemical constitutions of the plant until now. The contents of compounds E1 and E4–E7 in GG were significantly higher than those in WG in high-performance liquid chromatography analysis, and they also showed observably phytotoxic activities against lettuce and Festuca arundinacea.

Sky subtraction is the key technique in data reduction of multi-fiber spectra. Knowledge of the related instrument character is necessary to determine the method adopted in sky subtraction. In this study, we described the sky subtraction method designed for LAMOST(Large sky Area Multi-Object fiber Spectroscopic Telescope) survey. The method has been intergrated into LAMOST 2D Pipeline v2.6 and applied to data of LAMOST DR3 and later. For LAMOST, sky emission line calibration is used to alleviate the position-dependent (thus time-dependent) ~4% fiber throughput uncertainty and the small wavelength instability (0.1\AA ) during observation. PCA (Principal Component Analysis) sky subtraction further reduces 25% of the sky line residual of the OH lines in the red part of the LAMOST spectra after the mater sky spectrum, which is derived from a B-spline fit of 20 sky fibers in each spectrograph, is adjusted by sky emission line and subtracted from each fiber. Further analysis shows that our wavelength calibration accuracy is about 4.5km/s, and the average sky subtraction residuals are about 3% for sky emission lines and 3% for continuum region. The relative sky subtraction residuals vary with the moon light background brightness, could reach as low as 1.5% for the sky emission line regions in the dark night. Tests on the F stars of both similar sky emission line strength and similar object continuum intensity show that the sky emission line residual of LAMOST is smaller than those of SDSS survey., Comment: 28 pages, 13 figures, 2 tables, accepted by RAA

Vibrio spp. are pathogens of many bacterial diseases which have caused great economic losses in marine aquaculture. The strategy of alternative medical treatment that is utilised by herbalists has expanded in the past decade. The aim of our study is to discover the antibacterial molecules against Vibrio spp. Bacterial growth inhibition, membrane permeabilisation assessment and DNA interaction assays, as well as agarose gel electrophoresis, were employed to elucidate the antibacterial activity of hydroxytyrosol acetate. Results showed that hydroxytyrosol acetate had antibacterial activity against Vibrio spp. and it played the role via increasing bacterial membrane permeabilisation. The DNA interaction assay and agarose gel electrophoresis revealed that hydroxytyrosol acetate interacted with DNA. Hydroxytyrosol acetate enhanced the fluorescent intensity of DNA binding molecules and mediated supercoiled DNA relaxation. The present study provides more evidence that hydroxytyrosol acetate is a novel antibacterial candidate against Vibrio spp.

In this work, we present a catalog of 2651 carbon stars from the fourth Data Release (DR4) of the Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST). Using an efficient machine-learning algorithm, we find out these stars from more than seven million spectra. As a by-product, 17 carbon-enhanced metal-poor (CEMP) turnoff star candidates are also reported in this paper, and they are preliminarily identified by their atmospheric parameters. Except for 176 stars that could not be given spectral types, we classify the other 2475 carbon stars into five subtypes including 864 C-H, 226 C-R, 400 C-J, 266 C-N, and 719 barium stars based on a series of spectral features. Furthermore, we divide the C-J stars into three subtypes of CJ( H), C-J(R), C-J(N), and about 90% of them are cool N-type stars as expected from previous literature. Beside spectroscopic classification, we also match these carbon stars to multiple broadband photometries. Using ultraviolet photometry data, we find that 25 carbon stars have FUV detections and they are likely to be in binary systems with compact white dwarf companions., Comment: 72 pages, 23 figures. accepted by ApJS, lal@nao.cas.cn

In this article, a facile method to measure pH and calcium content of different kinds of eggs by Ion-selective electrodes was presented successfully. First of all, we used pH electrode to measure the pH value of egg yolk and protein respectively. For the native egg, yolk’s pH was 6.20 and protein’s pH was around 9.45. But the fresh egg yolk was different from the native hen egg, yolk’s pH was 6.20 and protein’s pH was approximately 9.20. Then, we chose calcium ion selective electrode to measure calcium content in the eggs. When it came to calcium content, there was an obvious difference between the native hen egg and the fresh egg. Calcium contents in egg yolk of the former ones are higher than that of the latter. Ion-selective electrode with these advantages makes it possible to measure composition content rapidly of eggs. This paper may be a guide to expand its application scope, further research must be continued in order to achieve big success.

The milling experiments were carried out using TiAlN and PCD coated carbide tools in high speed milling Ti6Al4V to compare and analyze tool wear and tool life of the two kinds of coating carbide tools. In addition, the effect of cooling and lubricating on tool wear is also studied. The results showed that fluid environment is not suitable for milling Ti6Al4V. PCD coating carbide tool can effectively increase the life of tool in high speed milling of Ti6Al4V.

The effect of photoinitiator content and species for adhesive liquid-solid conversion rate was studied. The infrared spectras of the alicyclic epoxy resin adhesives before and after the UV light curing were detected by FTIR. Thus light curing process for the alicyclic epoxy adhesive material was explored. The results showed that the UV light curing speed of Omnicat 550 was slower than that of Omnicat 650. Furthermore, the liquid-solid conversion rate was the maximum when the photoinitiator was added up to 3% with the same agent and coating thickness.

In this paper the characterization of the edge crack in the strip steel are studied by using numerical simulation method. The developments of the stress and strain near the crack tip are obtained and the value of the J-integral of edge crack under the rolling process is then examined. FE simulation result shows that the J-integral is not always path independent in the whole rolling process. When the crack is far away from the roller, the J-integral is path independent. When the crack enters the cold rolling region, the unload phenomena will occur near the crack tip which cause the incremental theory of plasticity failed and the conservation of the J-integral is not valid any more. The J-integral failure region is then determined by a series of FE simulations.

Six new highly oxygenated eudesmane sesquiterpenoid glucosides, senedensiscins A-F (1-6), were isolated from the aerial parts of Senecio densiserratus. Their structures with the absolute configurations were established on the basis of spectroscopic analyses and chemical methods. These compounds represent an unprecedented type of sesquiterpenoid glucoside with the angeloyl group directly connected to the glucosyl moiety and their cytotoxicity was evaluated against the selected human cell lines, HL-60, SMMC-7721, and HeLa. (C) 2013 Elsevier Ltd. All rights reserved.

Aiming at the present serious situation of heavy metals contaminated soil in lead-zinc mining area of Huize County. This paper analyzed the the Pb, Zn, Cu and Cd enrichment characteristics of Imperata cylindrica growing in the different distance from the abandoned smelter. Results showed that the content of heavy metals in soils showed a tendency to decrease with increasing distance from the abandoned smelter, and the content of heavy metals in the soil 50m away from the abandoned smelter was the highest. There was a significant positive correlation between the contents of Pb, Zn, Cu and Cd in Imperata cylindrica and soil around the abandoned smelter. Four heavy metals of Imperata cylindrica showed that the content of the underground part was higher than that of the aboveground part. These Results showed that Imperata cylindrica could absorb and enrich a variety of heavy metals and had the characteristics of heavy metal resistance. Based on the characteristics of large biomass and fast growth rate, Imperata cylindrica has a good application prospect as a heavy metal pollution restoration plant.

Various planting densities (5, 10, or 20 plants per tank) of Pontederia cordata were water-cultivated in purifying tanks to treat polluted water. Seasonal effects of the planting densities on the water quality improvement and the morphology and physiology of the plant were analyzed. Results indicated that planting densities affected the nitrogen and phosphorus removal of water, and the morphology and physiology of plants, including activity of peroxidise and catalase, content of chlorophyll and soluble protein (SP), the length of root, stem and leaf, tiller number and root density. When planting density increased from 10 to 20 plants per tank, the morphology and physiology of plants, and the nitrogen and phosphorus removal by plants improved slowly, but caused a tiller number decline in individual plants. This variation was significant in autumn, and associated with seasonal variations of plant physiology. During autumn, there were 26 tillers in each plant with 10 plants per tank, compared to 14 tillers per plant with 20 plants per tank. Increase in the nitrogen and phosphorus contents of the plants for 5-10 plants per tank was 5.41 and 0.79 g kg(-1), compared to 1.17 and 0.12 g kg(-1) for 10-20 plants per tank, respectively.

Experimental and numerical investigations have been carried out to study the effect of processing parameters on edge cracks in cold rolling process of silicon steels. The onset of edge cracks has been simulated by using finite element method (FEM) based on the Gurson–Tvergaard–Needleman damage model. Factorial design and Taguchi experimental design methods have been proposed to analyze the effects of reduction ratio, tension, work roll diameter, and friction coefficient on the formation of edge cracks. Parametric studies indicated that with the increasing of reduction ratio, friction coefficient, and tension, the crack length increases. A bigger work roll is beneficial to restrict the edge crack growth as well. The rank according to the impact degrees on the crack initiation from high to low is reduction ratio, tension, work roll diameter, and friction coefficient. Meanwhile, the combined effect curve of reduction ratio and tension on crack length was obtained which was validated by the experimental resul...

To characterize the degradation of material at low triaxiality, the shear modified GTN damage model proposed by Nahshon and Hutchinson (2008) was introduced in this study. The details of the numericalimplementation and validation of the model was conducted. And the shear modified parameter was determined by the comparisons of experimental and simulation results of the shear test. Then, the damage model was employed to simulate the cold rolling process, and the results showed that the shear modified GTN model can reveal the damage behavior and predict edge crackingof ductile materials in cold rolling.

A new Ti-based amorphous alloy Ti35Zr21Cu40Si4 with about 80 μm thickness and 5~8 mm width was fabricated by melt spinning method. The phase structure and thermal stabilities of the Ti35Zr21Cu40Si4 amorphous alloy were investigated by the X-ray diffraction (XRD) and differential scanning calorimetry (DSC), respectively. The Ti35Zr21Cu40Si4 amorphous alloy was cultivated in the simulate body fluid (SBF) for 15 days. And the blood compatibility was evaluated by dynamic clotting time and hemolysis rate test. The Ti35Zr21Cu40Si4 alloy exhibits fully amorphous phase and high thermal stability with a supercooled liquid region (ΔTx) of 80K. The Ca phosphates depositions on alloy surfaces were gained after 15 days. Moreover, n (Ca)/n (P) atom ratio of the deposition is about 1.65/1, which approaches to that of human bone 1.66/1, suggesting that the Ti35Zr21Cu40Si4 amorphous alloy is with an excellent biocompatibility. The Ti35Zr21Cu40Si4 amorphous ribbon has lower hemolysis ratio of 0.562%, which can reduce wrecking degree of erythrocytes, compared with medical standards of the hemolysis rate (less than 5%). These are favorable for application to biomaterials.

In this paper the behavior of crack propagation of the strip steel is investigated by using the Gurson-Tvergaard-Needleman (GTN) damage model. The damage parameters used in the damage model are determined by tension experiments and SEM observation. With the aid of finite element method the influences of rolling ruduction and tension on crack propagation are systematically analyzed. The numerical results show that the GTN damage model is available to prediction the initiation and propagation of edge cracks during rolling forming process and the simulation results agrees well with the experimental results.