C（m十b，m）的确定

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Correlation of Cooperatively Localized Rearrangement on the ＂Fluidized Domain＂ of Polymers to Their Nonexponentially Viscoelastic Behaviors at Double Aging Processes （I）： A Set of Reduced Universal Equations on the Stress Relaxation Modulus and Creep Comp

Based on the structure of glass （or liquid） polymers consisting of α-domain, β-co-domain, and entanglement constituent chain networks, and the nonexponentially viscoelastic behavior, a “heterophase fluctuation” model was proposed. It was found that the dynamics of cooperative rearrangement on the “fluidized domain” has a great shear rate, domain size, and temperature dependences. When the shear rate, domain size, and temperature dependences were taken account into the cooperatively localized rearrangement on the fluidized domain by the degradation of primary α-domain and the reformation of secondary β-co-domain constituent chains. A new dynamic theory of cooperatively localized rearrangement on the fluidized domain constituent chains with different size and different network chain length during physical and mechanical aging was established. The total viscoelastic free en-ergy of deformation resulting from the change in conformations of α-domain, β-co-domain, crytallite, crosslinked, and trapped entanglement constituent chains during aging processes was calculated by the combining method of kinetics and statistical mechanics. The constitu- tive equations and reduced stress relaxation modulus and creep compliances for three types of polymers were also derived. Finally, two reduced universal equations on creep compliance and stress relaxation modulus with a non-linear and two nonexponential parameters α and β were theoretically derived from the dynamic theory and a statistically extended mode coupling theory for double aging effects of polymers was developed. Results show that the two reduced universal equations have the same form as Kohlraush-Williams-Watts （K-W-W） stretched exponential function. The nonlinearity and the nonexponentiality are, respectively, originated from the memory effects of nonthermal and thermal history. The correlation of nonlinearity, α and β to the aging time, aging temperature, and the mesomorphic structure of fluidized domains was also established.

Calculation and analysis of losses of magnetic-valve controllable reactor

Magnetic-valve controllable reactor(MCR)has characteristics of DC bias and different types of magnetic flux density in the magnetic circuit and winding current distortion.These characteristics not only lead to loss calculation method of MCR different from that of power transformer,but also make it more difficult to calculate the core loss and wingding loss of MCR accurately.Our study combines core partition method with dynamic inverse J-A model to calculate the core loss of MCR.The winding loss coefficient of MCR is proposed,which takes into account the influence of harmonics and magnetic flux leakage on the winding loss of MCR.The result shows that the proposed core loss calculation method and winding loss coefficient are effective and correct for the loss calculation of MCR.

Intercropping Cocoa with Rice and Plantain Influencing Cocoa Morphological Parameters and Weed Biomass

A field study was conducted at CRIN Uhonmora Substation, Edo State in Derived Guinea Savanna Zone of Nigeria between 2007 and 2008. The experiment determined influence of intercropping cocoa with rice and plantain at early stage of field establishment. Four treatments considered were cocoa （sole）, cocoa/rice, cocoa/plantain and cocoa/rice/plantain. Spacing of 3.1 m apart was used for cocoa and plantain while rice was 30 cm. Plot laid out was randomized complete block design replicated three times. Data on cocoa morphological parameters comprising plant height, girth and leaf area as well as weed biomass were measured monthly. Cocoa survival count was also determined. Data collected were subjected to ANOVA, and LSD was used to separate the means. Survival count showed over 95% survival in all treatments without any significance differences. On plant height and leaf area vegetative growth were significantly higher （P 〈 0.05） in the intercrops than the sole cocoa but not significantly different in all the months. Plant vigour was significantly higher in cocoa/plantain intercrop. Cocoa/rice/plantain produced the least weed biomass while cocoa sole gave the highest. Therefore, cocoa/rice and cocoa/plantain intercrops could be recommended to cocoa farmers in Nigeria instead of sole planting at early age of field establishment.

Field Establishment of Cashew （Anacardium occidentale L,） Transplants as Affected by Nursery Periods

Field establishment of cashew has been seriously hampered by long delay in the nursery. This has led to transplanting of overgrown seedlings resulting in high transplant mortality, especially during the first dry season on the field. The experiment was set up to study field establishment of cashew transplants as affected by the nursery periods. Four nursery periods were tried. These were cashew transplanted at 3, 4, 8 and 12 weeks after sowing （WAS）. The experiment was laid out in randomized complete block with three replicates. Records were taken on morphological parameters and survival percentage of the transplants till fruiting. Cashew seedlings transplanted at 12 WAS had better morphological plant parameters compared to other transplants. At 3 months after transplanting （MAT）, cashew transplants of 12 WAS were 172.6%, 93.7% and 38.5% taller than transplants of 3, 4 and 8 WAS, respectively and the differences were significant （P 〈 0.05）. Similarly, seedlings transplanted at 12 WAS had 245.4%, ! 51.9% and 99.4% more leaves than those of 3, 4 and 8 WAS at 3 MAT, respectively. However, the survival percent of cashew seedlings transplanted at 12 WAS were 66.7% followed by that of 3 WAS with 75.0% within 12 MAT. No transplant mortality was incurred in seedlings transplanted at 4 and 8 WAS up to 12 MAT. For optimum growth and high survival rate, transplanting cashew seedlings between 4 and 8 WAS will be encouraged so as to have high plant stands, thereby, reducing supply in the following planting season.

Trends in major and minor meteorological variables and their influence on reference evapotranspiration for mid Himalayan region at east Sikkim, India

Abstract： Estimation of evapotranspiration （ET） for mountain ecosystem is of absolute importance since it serves as an important component in balancing the hydrologic cycle. The present study evaluates the performance of original and location specific calibrated Hargreaves equation （HARG） with the estimates of Food and Agricultural Organization （FAO） Penman Monteith （PM） method for higher altitudes in East Sikkim, India. The results show that the uncalibrated HARG model underestimates ET0 by 0.35 mm day^-1 whereas the results are significantly improved by regional calibration of the model. In addition, this paper also presents the variability in the trajectory associated with the climatic variables with the changing climate in the study site. Non- parametric Mann-Kendall （MK） test was used to investigate and understand the mean monthly trend of eight climatic parameters including reference evapotranspiration （ET0） for the period of 1985 - 2009. Trend of ET0 was estimated for the calculations done by FAO PM equation. The outcomes of the trend analysis show significant increasing （p ≤ 0.05） trend represented by higher Z-values, through MK test, for net radiation （Rn）, maximum temperature （Tmax） and minimum temperature （Train）, especially in the first months of the year. Whereas, significant （0.01 ≥ p ≤0.05） decreasing trend in vapor pressure deficit （VPD） and precipitation （P） is observed throughout the year. Declining trend in sunshine duration, VPD and ET0 is found in spring （March - May） and monsoon （June - November） season. The result displays significant （0.01≤ p ≤0.05） decreasing ET0 trend between （June - December） except in July, exhibiting the positive relation with VPD followed by sunshine duration at the station. Overall, the study emphasizes the importance of trend analysis of ET0 and other climatic variables for efficient planning and managing the agricultural practices, in identifying the changes in the meteorological parameters and to accurately assess the hydrologic water balance of the hilly regions.

Post-Fertilization Development of Seed in French Bean Genotypes： Changes in Seed Quality

An experiment was conducted to evaluate physiological maturity of French bean genotypes at District Seed Farm ＂D＂ Block, Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal during winter season of both 2012-2013 and 2013-2014. All the five genotypes were grown with sufficient population in three replications following randomized block design （RBD） for the purpose of developmental studies. Developing pods were harvested at different stages, starting from 7 days after anthesis （7 DAA） to 49 DAA with an interval of 7 d, including the field maturity stage, thus leading to study on maximum seven different stages. Harvested pods and seeds were utilized for this development programme through dry seed weight, germination and vigour index. Enhancement in dry matter accumulation in seed continued till 42 DAA for Selection 9 and Victoria in both the years; it was 49 and 42 DAA for Sonali in respective years; it was 49 DAA for Abhay in both the years; and for Deepali, it was 42 DAA along with statistically similar magnitude at 49 DAA. Significant enhancement in germination potential of developing seeds continued till 42 DAA for Selection 9 and Deepali, while it was 49 DAA for the other three genotypes. Enhancement in vigour index continued till 49 DAA for all the genotypes except for Selection 9, for which it continued till 42 DAA and then declined.

Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters

Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and October 2006. Four fish assemblages were identified in each survey using two-way indicator species analysis (TWIA). High fish biomass was found in the northern part, central part and coastal waters of the survey area; in contrast, high fish diversity was found in the southern part of the survey area and the Changjiang estuary outer waters. Therefore, it is difficult to maintain high fishery production when high fish diversity is evenly distributed in the fish community. Fish became smaller and fish size spectra tended to be narrower because of fish species variations and differences in growth characteristics. Fish diversity increased, the age to maturity was reduced and some migrant species were not collected in the surveys. Fish with low economic value, small size, simple age structure and low tropic level were predominant in fish assemblages in the Changjiang estuary and its adjacent waters. The lowest hypoxic value decreased in the Changjiang estuary and its adjacent waters.

The Effect of Utilisation on the Floristic Composition of Meadow Communities

This study presents research results which comprise the following selected communities： Phalaridetum arundinaceae, Alopecuretum pratensis, community with Deschampsia caespitosa, Holcetum lanati, Lolio-Cynosuretum, community Poa pratensis-Festuca rubra. The investigated phytocenoses developed in conditions of lack of utilisation, occasional cutting, occasional alternating meadow-pasture utilisation, pastures with uncut left-overs, 2 cuts and light grazing of the sward by cattle and 2-3 cuts. For the above-mentioned communities the following parameters were assessed： total species number and mean number of species in a phytosociological rel6ves besides Shannon-Wiener diversity index （H＇）, proportion of synanthropic species, natural valorisation number according to Ogwit and fodder value score （FVS）. Regular sward utilisation of plant communities exerts a positive impact not only on the natural values as evidenced by the total and mean number of species in a phytosociological survey and higher biodiversity index （H＇） but it also impacts the sward fodder value scores of meadows and pastures. The strongest negative influence on the floristic composition of meadow communities and their stability is exerted by sporadic, incorrect utilization as it favours taking over of green areas by grass expansive species and development of communities of low natural and use values （community with Deschampsia caespitosa, Ass. Holcetum lanati and community with Agropyron repens）. The strongest impact on the maintenance of meadow and pasture biological stability in the examined region is exerted by their regular, moderate cutting or grazing.

Responses of Soil Nematode Abundance and Diversity to Long-Term Crop Rotations in Tropical China

A field experiment was carried out from 2003 to 2013 in the Wanzhong Farm of the Hainan Island, China, to determine the effects of two long-term banana rotations on the abundance and trophic groups of soil nematode communities in the island. The experiment was set out as a randomized complete block design with three replications of three treatments： banana-pineapple rotation （AB）, banana-papaya rotation （BB） and banana monoculture （CK） in a conventional tillage system. Soil samples were taken at depths of 0-10, 10-20 and 20-30 cm, and nematodes were extracted by a modified cotton-wool filter method and identified to the genus level. Nematode ecological indices of Shannon-Weaver diversity （Ht）, dominance index （A）, maturity index （MI）, plant parasite index （PPI）, structure index （SI）, enrichment index （EI）, and channel index （CI） were calculated. A total of 28 nematode genera with relative abundance over 0.1% were identified, among which Tylenchus and Paratylenchus in the AB, Thonus in the BB, Tylenchus and Helicotylenchus in the CK were the dominant genera. The rotation soils favored bacterivores, fungivores and omnivores-predators with high colonizer-persister （c-p） values. Soil food web in the rotation systems was highly structured, mature and enriched as indicated by SI, MI and EI values, respectively. Higher abundance of bacterivores and lower values of CI suggested that the soil food web was dominated by a bacterial decomposition pathway in rotation soils. Nematode diversity was much higher after a decade of rotation. Soil depth had significant effects on the abundance of soil nematodes, but only on two nematode ecological indices （λ and MI）.

PARAMETER ESTIMATION OF EXPONENTIAL DISTRIBUTION

Because of the importance of grouped data, many scholars have been devoted to the study of this kind of data. But, few documents have been concerned with the thresh-old parameter. In this paper, we assume that the threshold parameter is smaller than the first observing point. Then, on the basis of the two-parameter exponential distribution, the maximum likelihood estimations of both parameters are given, the sufficient and necessary conditions for their existence and uniqueness are argued, and the asymptotic properties of the estimations are also presented, according to which approximate confidence intervals of the parameters are derived. At the same time, the estimation of the parameters is generalized, and some methods are introduced to get explicit expressions of these generalized estimations. Also, a special case where the first failure time of the units is observed is considered.

Large-area gold nanohole arrays fabricated by one-step method for surface plasmon resonance biochemical sensing

Surface plasmon resonance(SPR) nanosensors based on metallic nanohole arrays have been widely reported to detect binding interactions in biological specimens. A simple and effective method for constructing nanoscale arrays is essential for the development of SPR nanosensors. In this work, we report a one-step method to fabricate nanohole arrays by thermal nanoimprinting in the matrix of IPS(Intermediate Polymer Stamp). No additional etching process or supporting substrate is required. The preparation process is simple, time-saving and compatible for roll-to-roll process, potentially allowing mass production. Moreover, the nanohole arrays were integrated into detection platform as SPR sensors to investigate different types of biological binding interactions. The results demonstrate that our one-step method can be used to efficiently fabricate large-area and uniform nanohole arrays for biochemical sensing.

Distinguishability analysis of controller parameters with applications to DFIG based wind turbine

The power system controllers normally have more than one parameter.The distinguishability analysis of the controller parameters is to identify whether the optimal set of the parameters of the controllers is unique.It is difficult to obtain the analytic relationship between the objective of the optimization and the controller parameters,which means that the analytical method is not suitable for the distinguishability analysis.Therefore,a trajectory sensitivity based numerical method for the distinguishability analysis of the controller parameters is proposed in this paper.The relationship between the distinguishability and the sensitivities of the parameters is built.The magnitudes of the sensitivities are used to identify the key parameters,while the phase angles of the sensitivities are used to analyze the distinguishability of the key parameters.The distinguishability of the controller parameters of wind turbine with DFIG is studied using the proposed method,and dynamic simulations are performed to verify the results of the distinguishability analysis.