Mesoscale Numerical Simulation Study of Warm Fog Dissipation by Salt Particles Seeding

Based on the dynamic framework of WRF and Morrison 2-moment explicit cloud scheme, a salt-seeding scheme was developed and used to simulate the dissipation of a warm fog event during 6–7 November 2009 in the Beijing and Tianjin area. The seeding effect and its physical mechanism were studied. The results indicate that when seeding fog with salt particles sized 80 μm and at a quantity of 6 gm^（-2） at the fog top, the seeding effect near the ground surface layer is negative in the beginning period, and then a positive seeding effect begins to appear at 18 min, with the best effect appearing at 21 min after seeding operation. The positive effect can last about 35 min. The microphysical mechanism of the warm fog dissipation is because of the evaporation due to the water vapor condensation on the salt particles and coalescence with salt particles.The process of fog water coalescence with salt particles contributed mostly to this warm fog dissipation. Furthermore, two series of sensitivity experiments were performed to study the seeding effect under different seeding amounts and salt particles sizes. The results show that seeding fog with salt particles sized of 80 μm can have the best seeding effect, and the seeding effect is negative when the salt particle size is less than 10 μm. For salt particles sized 80 μm, the best seeding effect, with corresponding visibility of 380 m, can be achieved when the seeding amount is 30 g m^（-2）.

Path analysis and estimation of additive and epistatic gene effects of barley SSD lines

In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of correlation. The direct and indirect effects of such components on grain weight per plant and 1 000-grain weight were estimated using path analysis. In the 2006 and 2007, the spike length and number of spikelets per spike were the determinants of grain weight. Genetic parameters as additive and epistasis effects were estimated for all studied traits. The results indicate the importance of both additive and epistasis gene effects of number of spikes per plant, grain weight per spike, grain number per plant and grain weight per plant in this study.

Study on mutagenic effects of rice seeds irradiated by CO_2 laser

Seeds of japonica rice (cv. Zhenuo 2) at twodifferent physiological states (dry seeds withwater content 13% and wet seeds soaked inthe water for 36 h) were irradiated by COlaser in four different power-densities. Theseeds irradiated by 200GY ofCo γ rays andno radiated seeds were used as the controls.Results showed that the biological effects

Analysis of seed and maternal genetic effects on cooking quality characters in indica hybrid rice

We analysed seed and maternal genetic effects on characters of cooking quality in indica hybrid rice by using the model for quantitative characters of seeds of cereal crops. Incomplete diallel crosses were made by using six male sterile lines (Zhenshan 97A, Erjiuqing A, Erjiunan 1A, V20A, Zhe’nan 1A and Zhe’nan 3A)as females and three restorer lines(Cezao 2-2, T49 and 26715)as males. Sampled seeds were used to measure the cooking quality characters, including amylose content(%), gelatinization temperature(alkali spreading score)and gel consistency(mm). Results indicated that some rice cooking quality characters were controlled by both seed genes and maternal genes (see table). Gel consistency was mainly controlled by maternal effects, but also

Spatial Control of Lithium Deposition by Controlling the Lithiophilicity with Copper(Ⅰ)Oxide Boundaries

Spatial control of lithium deposition is the most important issue in lithium-metal batteries because of the considerable control of lithium dendrite suppression via the uniform distribution of Li^(+)flux.Although seed materials are crucial for the behavior of lithium deposition,in-depth studies on their physical and chemical control have not been conducted.Here,we describe a new design of seed structure comprising a wrinkled Cu/graphene substrate surrounded by copper(Ⅰ)oxide(Cu_(2)O)on a graphene grain boundary over a large area,which is fabricated by the oxidation of the Cu surface via graphene boundary defects by using chemical vapor deposition(CVD).Scanning and transmission electron microscopy results reveal that Cu_(2)O on the graphene boundary can render a preferential reaction with lithium during the first deposition and assist in the uniform deposition of lithium by preventing the agglomeration of lithium clusters during the second deposition.This two-step process is attributed to the degree of selectivity due to the difference in lithium affinity,which allows long-term electrochemical stability and a high rate capability via boundary effects.This study highlights the significance of the boundary effect,which can open new avenues for the formation of a large family of seed structures in lithium-metal batteries.

Effect of Seed Coat on Drying Kinetics of Kidney Bean Seed

Kidney bean seed was dried in a laboratory scale fixed bed. The effect of seed coat on drying dynamic characteristics and the changes of seed coat structure were investigated. A mathematical model was established to simulate the drying process and determine the moisture diffusivity. Numerical results agree well with the experimental data. The average moisture diffusivity of the seed with separated coat is 1.67 times larger than that of the seed with coat, and the moisture diffusivity of seed cotyledon is 3.2 times larger than that of the seed coat. It is proved that the seed coat is the most main resistance of mass transfer and is also one of the key points of the optimization of heat and mass transfer for seed drying.

Microphysical Effects of Cloud Seeding in Supercooled Stratiform Clouds Observed from NOAA Satellite

Based on the satellite retrieval methodology, the spectral characteristics and cloud microphysical properties were analyzed that included brightness temperatures of Channels 4 and 5, and their brightness temperature difference （BTD）, the particle effective radius of seeded cloud track caused by an operational cloud seeding and the microphysical effects of cloud seeding were revealed by the comparisons of their differences inside and outside the seeded track. The cloud track was actually a cloud channel reaching 1.5-km deep and 14-km wide lasting for more than 80 min. The effective radius of ambient clouds was 10-15 μm, while that within the cloud track ranged from 15 to 26 μm. The ambient clouds were composed of supercooled droplets, and the composition of the cloud within the seeding track was ice. With respect to the rather stable reflectance of two ambient sides around the track, the visible spectral reflectance in the cloud track varied at least 10%, and reached a maximum of 35%, the reflectance of 3.7 μm in the seeded track relatively decreased at least 10%. As cloud seeding advanced, the width and depth were gradually increased. Simultaneously the cloud top temperature within the track became progressively warmer with respect to the ambient clouds, and the maximum temperature differences reached 4.2 and 3.9℃ at the first seeding position for Channels 4 and 5. In addition, the BTD in the track also increased steadily to a maximum of 1.4℃, compared with 0.2-0.4℃ of the ambient clouds. The evidence that the seeded cloud became thinner comes from the visible image showing a channel, the warming of the cloud tops, and the increase of BTD in the seeded track. The seeded cloud became thinner mainly because the cloud top descended and it lost water to precipitation throughout its depth. For this cloud seeding case, the glaciation became apparent at cloud tops about 22 min after seeding. The formation of a cloud track in the supercooled stratiform clouds was mainly because that the seeded cloud volume glaciated into ice hydrometeors that precipitated and so lowered cloud top height. A thin line of new water clouds formed in the middle of the seeded track between 38 and 63 min after seeding, probably as a result of rising motion induced by the released latent heat of freezing. These clouds disappeared in the earlier segments of the seeded track, which suggested that the maturation of the seeding track was associated with its narrowing and eventual dissipation due to expansion of the tops of the ambient clouds from the sides inward.

Effective Seed Distribution Pattern of an Upward Shift Species in Alpine Tundra of Changbai Mountains

The vegetation of alpine tundra in the Changbai Mountains has experienced great changes in recent decades. Narrowleaf small reed(Deyeuxia angustifolia), a perennial herb from the birch forest zone had crossed the tree line and invaded into the alpine tundra zone. To reveal the driven mechanism of D. angustifolia invasion, there is an urgent need to figure out the effective seed distribution pattern, which could tell us where the potential risk regions are and help us to interpret the invasion process. In this study, we focus on the locations of the seeds in the soil layer and mean to characterize the effective seed distribution pattern of D. angustifolia. The relationship between the environmental variables and the effective seed distribution pattern was also assessed by redundancy analysis. Results showed that seeds of D. angustifolia spread in the alpine tundra with a considerable number(mean value of 322 per m2). They were mainly distributed in the low elevation areas with no significant differences in different slope positions. Effective seed number(ESN) occurrences of D. angustifolia were different in various plant communities. Plant communities with lower canopy cover tended to have more seeds of D. angustifolia. Our research indicated reliable quantitative information on the extent to which habitats are susceptible to invasion.

Bulbuls and crows provide complementary seed dispersal for China's endangered trees

Background: Different functional frugivores generally exhibit unequal contributions,both in terms of quantity(seed removal) and quality(seedling recruitment),to effective seed dispersal of plant species.However,variations in this dispersal pattern generated by frugivores across different regions are still unknown.Methods: In our study,we evaluated the contributions of two functional frugivore bird groups,the bulbuls(Pycnon?otidae) and crows(Corvidae),in both the seed removal and seedling recruitment of the endangered Chinese yew tree(Taxus chinensis) across three different geographical regions in eastern China.Results: The dominant crow species,Urocissa erythrorhyncha,was the most common disperser crow species at all sites,while the dominant bulbul species varied across the three sites.Furthermore,the two functional groups of dispersers diverged in the aspects of seed removal(quantity) and seedling recruitment pattern(quality).While bulbuls outperformed crows in seed removal(quantity),crows took more seeds to a safer site for seedlings(quality).Conclusions: Our results highlight the importance of variations in the effective seed dispersal patterns of different functional disperser groups across different regions in the conservation and management of endangered tree species.

Fabrication of large-scale ripples on fluorine-doped tin oxide films by femtosecond laser irradiation

The large-scale uniform self-organized ripples are fabricated on fluorine-doped tin oxide （FTO） coated glass by femtosecond laser. They can be smoothly linked in a horizontal line with the moving of XYZ stage by setting its velocity and the repetition rate of the laser. The ripple-to-ripple linking can also be realized through line-by-line scanning on a vertical level. The mechanism analysis shows that the seeding effect plays a key role in the linking of ripples.

Production of Sucrose Crystals of Uni-Modal Size Distribution by Seeded Batch Cooling Crystallization

From sucrose aqueous solution of high viscosity, sucrose was crystallized by seeded cooling in a batch crystallizer. At low seed loadings, the product crystal size distribution (CSD) was wide-spread because of enormous secondary and primary nucleation. However, at high seed loadings, it became uni-modal, where the crystallization was dominated by seed growth with practically no secondary nucleation. Enough seeding was thus effective in suppressing nucleation even during batch crystallization with high viscosity solution. The volume mean size of the product crystals obtained at high seed loadings agreed with that calculated by a simple mass balance assuming growth-dominated crystallization with no change in the number of crystals.

Effect of seed soaked with urea solution on the cold tolerance of rice seedlings

In the Yangtze river aera,the first crop of indi-ca rice is sown in late Mar to early Apr andtransplanted in early May.Usually,seedlingsperish when abnormal low temperature of 6-10℃ lasted for 3 d or longer.The effect ofsocking seed with urea solution on increasingthe cold tolerance at the seedling stage was

Natural continuous influent nitrifier immigration effects on nitrification and the microbial community of activated sludge systems

Two sequencing batch reactors（SBRs） were operated for 100 days under aerobic conditions,with one being fed with unsterilized municipal wastewater（USBR）, and the other fed with sterilized municipal wastewater（SSBR）. Respirometric assays and fluorescence in situ hybridization（FISH） results show that active nitrifiers were present in the unsterilized influent municipal wastewater. The maximum ammonia utilization rate（AUR） and nitrite utilization rate（NUR） of the unsterilized influent were 0.32 ± 0.12 mg NH4＋-N/（L·hr） and0.71 ± 0.18 mg NO2--N/（L·hr）. Based on the maximum utilization rates, the estimated seeding intensity for the ammonia oxidizing bacteria（AOB） and nitrite oxidizing bacteria（NOB） of the USBR was 0.08 g AOB/（g AOB·day） and 0.20 g NOB/（g NOB·day） respectively. The fraction of nitrifiers/total bacteria in the influent was 5.35% ± 2.1%, the dominant AOB was Nitrosomonas spp., Nitrosococcus mobilis hybridizated with Nsm156, and the dominant NOB was Nitrospira hybridizated with Ntspa662. The influent nitrifiers potentially seeded the activated sludge of the bioreactor and hence demonstrated a mitigation of the acclimatization times and instability during start-up and early operation. The AUR and NUR in the USBR was 15% and 13% higher than the SSBR respectively during the stable stage, FISH results showed that nitrifiers population especially the Nitrospira in the USBR was higher than that in the SSBR. These results indicate that the natural continuous immigration of nitrifiers from municipal influent streams may have some repercussions on the modeling and design of bioreactors.

Effects of seed particles Al2O3, Al2（SO4）3 and H2SO4 on secondary organic aerosol

Seed particles Al2O3, Al2（SO4）3 and H2SO4 were selected to investigate their effects on secondary aerosol （SA） formation in toluene/NOx photooxidation under sulfur dioxide （SO2） and ammonia （NH3）. Effect of seed particles on SA formation was related to their acid-base properties and the presence of acid or alkaline gases. Under NH3-poor condition, SA formation increased with increasing SO2 concentration due to the acid-catalyzing effect of the oxidation products of SO2 （i.e. H2SO4）, The enhancing effect of SO2 became unobvious under NH3-rieh condition, because NH3 would eliminate the acid-catalyzing effect by neutralizing the acid products. Acidic seeds H2SO4 accelerated SA formation under either SO2 or NH3 condition. Weak acidic Al2（SO4）3 seeds didn＇t affect obviously on SA formation. The inhibiting effect of amphoteric seeds Al2O3 on SA formation was related to the presence of SO2 / NH3 due to their acid-base property. Under NH3-poor condition, the inhibiting effect of Al2O3 on SA formation decreased with increasing concentration of SO2, while under NH3-rich condition, the inhibiting effect wasn＇t remarkable.

Influence of natural rainfall variability on the evaluation of artificial precipitation enhancement

Evaluating cloud seeding effects is one of the most critical issues in artificial precipitation enhancement experiments. However, the evaluation is not straightforward because there is natural rainfall variability, which subjects the atmosphere to spatiotemporal instabilities. The aim of this study is to analyze natural rainfall variability using the modern statistical simulation method, "bootstrap", to analyze its influence on the evaluation of seeding activities and to take proper measures to control the influence. The study is based on the 1997?2007 airborne seeding macro records and the daily precipitation data in Jilin Province. The influence of natural rainfall variability can be reduced through three approaches: the increase of the supposed "seeded" sample size N, the rejection of outliers, and the selection of similar control units. A larger N leads to smaller calculated precipitation variability and detectable lower limits of seeding effects. When N is near 470 and the seeding effect is between 20% and 30%, the confidence level reaches 90%. For a single seeding operation, the case deletion model that rejects strong influence points and selects similar control units is established to control the influence of natural precipitation variability, which obviously improves the evaluation of artificial precipitation enhancement. The results demonstrate that the relative seeding effect in Jilin Province is concentrated mainly in the range of 0 to 30%, with an average of 11.95%, and has no significant linear relationship with the actual precipitation amount. However, the fluctuation amplitude of the relative effect decreases as the precipitation amount rises.

Effectiveness of seed dispersal by ants in a Neotropical tree

Seed dispersal and subsequent recruitment is the template on which forest regeneration takes place.Hence,considering the scale over which ecological processes occur is key for understanding the overall impact of various dispersal agents.To explore leafcutter ant(Atta colombica)dispersal effectiveness in space and time,seed movement and subsequent recruitment of a large-seeded predominately vertebrate-dispersed tree,Simarouba amara(Aubl.Simaroubaceae),was investigated on Barro Colorado Island,Panama.At each of 218 reproductive-sized adults(>20 cm diameter at breast height),presence or absence of a leafcutter ant colony was noted,with extensive checks for Atta activity taking place at or in close proximity to seed and seedling transects,which extended 4 cardinal directions for 30 m from each reproductive female tree(n=74).Only at 2 S.amara trees were nests observed,and in these areas a dense S.amara seedling carpet was observed.Although nearby nest and dump sites might increase local S.amara recruitment in the short term,mortality at these sites is complete or nearly so.Hence,the seed dispersal effectiveness by leafcutter ants appears to be ephemeral and likely contributes inconsequentially to the long-term recruitment and distribution patterns of the species.This finding highlights the importance of evaluating disperser effectiveness at ecologically relevant spatiotemporal scales.