Physiological and Biochemical Responses of Perennial Ryegrass Mixed Planting with Legumes under Heavy Metal Pollution

In artificially controlled pot experiments,perennial ryegrass was mixed with other leguminous plants(white clo-ver and alfalfa)and treated with lead,zinc and cadmium(337 mg·kg^(-1),648 mg·kg^(-1),and 9 mg·kg^(-1),respectively)to simulate compound pollution conditions.The results showed that the concentrations of heavy metals,trans-port factors,and bioconcentration factors in mixed planting of ryegrass decreased compared with those in mono-culture.Regardless of whether heavy metal pollution was introduced,mixed planting increased the aboveground and underground biomasses of ryegrass.The different mixed planting treatments had no significant impact on the chlorophyll concentration of ryegrass.The mowing time,mixed planting treatment,and heavy metal treatment had impacts on antioxidant and osmotic adjustment substances,and there were some interactions.The mixed planting treatment did not significantly affect glutathione concentration,cysteine concentration,or nonprotein thiol.Mixed planting generally increased the nitrogen and phosphorus concentrations of ryegrass while reducing the stoichiometric ratio of carbon,nitrogen,and phosphorus.These results suggest that the mixed planting of ryegrass with legumes promotes the growth of ryegrass in the presence of high concentrations of heavy metal pollution.However,it does not enhance the ability of ryegrass to remediate heavy metal pollution in the soil.

Study on Addition Amount of Lactic Acid Bacteria and Cellulase in Mixed Silage of Potato Plants

[Objectives]This study was conducted to investigate the appropriate addition amounts of lactic acid bacteria and cellulase in the mixed silage of potato plants,so as to provide a basis for the rational use of potato plants.[Methods]Fresh potato(Solanum tuberosum)seedling plants,watermelon(Citrullus lanatus)plants,and melon(Cucumis melo)plants were selected as raw materials for silage,each of which was added at a ratio of 32%,and 4%of brown flour was added additionally.On this basis,an L 9(32)orthogonal experiment was designed to investigate the effects of the amount of lactic acid bacteria(10,20,30 g/kg)and the amount of cellulase(5,10,15 g/kg)on the experimental results with sensory evaluation score as an investigation index.[Results]With the increase of the amount of lactic acid bacteria and the amount of cellulase,the sensory evaluation score of silage increased,and it was the highest when the amount of lactic acid bacteria added was 20 g/kg and the amount of cellulose was 10 g/kg.With the increase of the amounts of lactic acid bacteria and cellulase added,ammonia nitrogen showed a decreasing trend,and the pH and ammonia nitrogen were the lowest when the amount of lactic acid bacteria added was 20 g/kg and the amount of cellulose was 10 g/kg.[Conclusions]This study provides a theoretical basis for the rational use of effective ingredients and nutrients in potato plants and the development of new feed resources.

A methodology of implementing target mixing ratio for asphalt mixture

In order to implement the objective mix design of hot mix asphalt adequately during the construction process, the significance of objective mixing ratio was elaborated, and the variability of materials and its control method were analyzed. An engineering example is used to illustrate the debugging process of asphalt mixture batching ＆ mixing plant and the dynamic quality management methods. The results show that the set of methods can not only implement the objective mixing ratio of hot mix asphalt adequately, but also control production during the construction process effectively.

Development of seeder for mixed planting of corn and soybeans

Corn and soybeans should be sown between 5 cm and 10 cm apart in mixed cultivation to increase protein content and improve productivity of the forage.However,existing sowers cannot plant at intervals of less than 20 cm.Consequently,mixed cultivation of corn and soybeans is currently performed by first sowing corn seeds with a tractor and then manually planting soybean seeds.This method results in irregular intervals between the seeds,it is laborious and time consuming.This study aimed at developing a seeder that can simultaneously,precisely and efficiently plant corn and soybean.The geometrical and rheological properties of corn and soybeans were initially measured.The seed conveying equipment were designed using the EDEM software.The sowing interval between seeds,depth of soil over planted seed,and sowing performance were analyzed.The EDEM simulation results indicated that a 6-mm-wide and 3-mm-deep grooved seed-delivering roller had the highest particle mobility of the designs considered,with a 2.5%misplanting rate.A performance test showed that no misplanting occurred in the sections sowed with soybean seeds at a seeding interval that averaged 32 mm(321 seeds sown in 10 m)and that misplanting occurred in one section sowed with corn at a seeding interval that averaged 247 mm(40 seeds sown over 10 m).The sowing efficiency for both corn and soybeans was found to be 0.42 h/hm2.The average depth of soil over seed was 32.7 mm for soybean and 39.7 mm for corn.These average depths are within the stipulated range for the depth of soil over seed,which is 5 to 10 times the seed size.This study developed an efficient seeding machine that can simultaneously plant soybean and corn precisely,consequently improving forage yield and saving man-hours.

Economics and Performance of 10 Gb/s Metro Transport Over Mixed Fiber Plant of G.655 NZDF and G.652.C Zero Water-Peak Fibers

Using lower-cost lasers, 30% savings are possible for 10-Gb/s uncompensated metro transmission over NZDF, compared to G.652 fiber. We present WDM transmission results for a mixed plant of NZDF rings interconnected to G.652.C-fiber access laterals.

Air pollutant emissions from the asphalt industry in Beijing,China

Improving our understanding of air pollutant emissions fromthe asphalt industry is critical for the development and implementation of pollution control policies.In this study,the spatial distribution of potential maximum emissions of volatile organic compounds(VOCs)in the complete life cycle of asphaltmixtures,as well as the particulate matter(PM),asphalt fume,nonmethane hydrocarbons(NMHCs),VOCs,and benzoapyrene(BaP)emissions from typical processes(e.g.,asphalt and concrete mixing stations,asphalt heating boilers,and asphalt storage tanks)in asphalt mixing plants,were determined in Beijing in 2017.The results indicated that the potential maximum emissions of VOCs in the complete life cycle of asphalt mixtures were 18,001 ton,with a large contribution from the districts of Daxing,Changping,and Tongzhou.The total emissions of PM,asphalt fume,NMHC,VOCs,and BaP from asphalt mixing plants were 3.1,12.6,3.1,23.5,and 1.9×10^(−3)ton,respectively.The emissions of PMfromasphalt and concretemixing stations contributed themost to the total emissions.The asphalt storage tankwas the dominant emission source of VOCs,accounting for 96.1%of the total VOCs emissions in asphalt mixing plants,followed by asphalt heating boilers.The districts of Daxing,Changping,and Shunyi were the dominant regions for the emissions of PM,asphalt fume,NMHC,and BaP,while the districts of Shunyi,Tongzhou,and Changping contributed the most emissions of VOCs.