259 research outputs found
Distribution of power requirements during yarn winding in ring spinning
A model of a yam package is established for a ring spinning system. The yarn layer, surface area, and mass of the yam package are formulated with respect to the diameters of the empty bobbin and full yarn package, yarn count, and yarn winding-on time. Based on the principles of dynamics and aerodynamics, models of the power requirements for overcoming the skin friction drag, increasing the kinetic energy of the yarn package (bobbin and wound yarn), and overcoming the yarn wind-on tension are developed. The skin friction coefficient on the surface of a rotating yam package is obtained from experiment. The power distribution during yam packaging is discussed based on a case study. The results indicate that overcoming the skin friction drag during yarn winding consumes the largest amount of energy. The energy required to overcome the yarn wind-on tension is also significant
Assessment and Spatiotemporal Variation Analysis of Water Quality in the Zhangweinan River Basin, China
AbstractSpatiotemporal variation analysis of water quality and identification of water pollution sources in river basins is very important for water resources protection and sustainable utilization. In this study, fuzzy comprehensive analysis and two statistical methods including cluster analysis and seasonal Kendall test method were used to evaluate the spatiotemporal variation of water quality in the Zhangweinan River basin. The results for spatial cluster analysis and assessment on water quality at 19 monitoring sites indicated that water quality in the Zhangweinan River basin could be classified into two regions according to pollution levels. One is the Zhang River basin located in northwest of the Zhangweinan River basin where water quality is good. Another one includes the Wei River and eastern plain of the Zhangweinan River basin, and the water pollution in this region is serious, where the pollutants from point sources flow into the river and the water quality changes greatly. The results of temporal cluster analysis and seasonal Kendall test indicated that the sampling periods may be classified into three periods during 2002-2009 according to water quality. Results of temporal cluster analysis and seasonal Kendall test indicated that the study periods may be classified into three periods and two different trends was detected during the period of 2002-2009. The first period was the year of 2002-2003, during which water quality had deteriorated and serious pollution was observed in the Wei River basin and eastern plain of the Zhangweinan River basin. The second period was the year of 2004-2006, during which water quality became better. The year of 2007-2009 is the third period, during which water quality had been improved greatly. Despite that water quality in the Zhangweinan River basin had been improved during the period of 2004-2009, water quality in the Wei River (southwestern part of the basin), the Wei Canal River and the Zhangweixin River (eastern plain of the basin) is still poor. These results provide may useful information for better pollution control strategies in the Zhangweinan River basin
Quantum secure communication scheme with W state
Recently, Cao et al. proposed a new quantum secure direct communication
scheme using W state. In their scheme, the error rate introduced by an
eavesdropper who takes intercept-resend attack, is only 8.3%. Actually, their
scheme is just a quantum key distribution scheme because the communication
parties first create a shared key and then encrypt the secret message using
one-time pad. We then present a quantum secure communication scheme using
three-qubit W state. In our scheme, the error rate is raised to 25% and it is
not necessary for the present scheme to use alternative measurement or Bell
basis measurement. We also show our scheme is unconditionally secure.Comment: Comments are welcom
FISH karyotype of 85 common wheat cultivars/lines displayed by ND-FISH using oligonucleotide probes
Fluorescence in situ hybridization (FISH) can reveal minor structural differences of chromosomes. The karyotype of common wheat (Triticum aestivum L.) based on FISH pattern is seldom reported. In this study, non-denaturing FISH (ND-FISH) using Oligo-pSc119.2-1, Oligo-pTa535-1 and (AAG)6 as probes was used to investigate the chromosomal structure of 85 common wheat including 83 wheat-rye 1RS.1BL translocation cultivars/lines, a wheatrye 1RS.1AL translocation cultivar Amigo and Chinese Spring (CS). Two, three, two, three, six, three and four structural types respectively for 1A, 2A, 3A, 4A, 5A, 6A and 7A chromosomes were observed. Two, eight, two, two, four and six types of chromosome for 2B, 3B, 4B, 5B, 6B and 7B were respectively detected. The structure of 1B chromosomes in Amigo and CS is different. Five, two, two and two types of chromosomal structure respectively for 1D, 2D, 3D and 5D were distinguished. Polymorphisms of 1RS.1BL, 4D, 6D and 7D chromosomes were not detected. Chromosomes 1AI, 2AI, 3AI, 4AI, 5AIII, 6AI, 7AIII, 2BI, 3BV, 4BI, 5BII, 6BIII, 7BI, 1DIV, 2DI, 3DI and 5DII appeared in these 85 wheat cultivars/lines at high frequency. Each of the 85 wheat cultivars/lines has a unique karyotype. Amigo is a complex translocation cultivar. The FISH karyotype of wheat chromosomes built in this study provide a reference for the future analyzing wheat genetic stocks and help to learn structural variations of wheat chromosomes. In addition, the results in this study indicate that oligonucleotide probes and ND-FISH technology can be used to identify individual wheat cultivar
Effects of Exogenous Cellulase Source on In Vitro Fermentation Characteristics and Methane Production of Crop Straws and Grasses
In vitro fermentation experiments were conducted to investigate the effects of 3 sources of
exogenous cellulase products (EC) at 4 dose rates (DR) (0, 12, 37 and 62 IU/g of DM) on degradation
of forage and methane production by mixed rumen micro-organisms of goats. The maximum gas
production (Vf) of grasses was higher (P<0.001) in Neocallimastix patriciarum (NP) group than those in
Trichoderma reesei (TR) and Trichoderma longibrachiatum (TL) groups. Quadratic increases in dry
matter degradation (DMD) of forage and neutral detergent fiber (NDFD) of straw were observed for all
EC, with optimum DR in the low range. Supplementation of EC originated from TR and NP increased
(P<0.001) DMD of forage compared to that from TL. Addition of EC originated from TR and NP also
decreased pH value, ammonia nitrogen (NH3-N) and methane (CH4) production compared to that from
TL. Quadratic decreases in pH value, NH3-N and CH4 of forage were noted for EC of TR and NP, and
with optimum DR in the low range. For short chain fatty acid, the EC of NP increased total volatile
fatty acid (TVFA) and acetate concentration and the ratio of acetate to propionate of forage compared
with EC of TL and TR, and with optimum DR in the low to medium range. It was concluded that the
source of EC differed in fiber degradation and methane emission, and with optimum DR of TR in the
low range (from 12 to 37 U/g DM) in improving fiber degradation and decreasing methane emission
Measurements of the observed cross sections for exclusive light hadrons containing at , 3.650 and 3.6648 GeV
By analyzing the data sets of 17.3, 6.5 and 1.0 pb taken,
respectively, at , 3.650 and 3.6648 GeV with the BES-II
detector at the BEPC collider, we measure the observed cross sections for
, , ,
and at the three energy
points. Based on these cross sections we set the upper limits on the observed
cross sections and the branching fractions for decay into these
final states at 90% C.L..Comment: 7 pages, 2 figure
Measurements of the Mass and Full-Width of the Meson
In a sample of 58 million events collected with the BES II detector,
the process J/ is observed in five different decay
channels: , , (with ), (with
) and . From a combined fit of all five
channels, we determine the mass and full-width of to be
MeV/ and
MeV/.Comment: 9 pages, 2 figures and 4 table. Submitted to Phys. Lett.
Partial wave analysis of J/\psi \to \gamma \phi \phi
Using events collected in the BESII detector, the
radiative decay is
studied. The invariant mass distribution exhibits a near-threshold
enhancement that peaks around 2.24 GeV/.
A partial wave analysis shows that the structure is dominated by a
state () with a mass of
GeV/ and a width of GeV/. The
product branching fraction is: .Comment: 11 pages, 4 figures. corrected proof for journa
Measurements of the observed cross sections for exclusive light hadron production in e^+e^- annihilation at \sqrt{s}= 3.773 and 3.650 GeV
By analyzing the data sets of 17.3 pb taken at GeV
and 6.5 pb taken at GeV with the BESII detector at the
BEPC collider, we have measured the observed cross sections for 12 exclusive
light hadron final states produced in annihilation at the two energy
points. We have also set the upper limits on the observed cross sections and
the branching fractions for decay to these final states at 90%
C.L.Comment: 8 pages, 5 figur
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