Doing a Good Job in Inspection and Maintenance of Facilities and Equipments in Bulk Curing Barn

Due to the limited management funds and insufficient management efforts,curing barns in traditional tobacco area are outdated and equipments are seriously damaged,which affects the normal operation and increases the maintenance cost of bulk curing barns,bringing adverse effects on tobacco leaf curing in the coming year and the sustainable development of tobacco industry in the future.To ensure the normal operation of curing barns and effectively prolong the service life of curing barns during tobacco leaf curing,we should do a good job in the publicity of management and maintenance,improve the system of management and maintenance,raise funds for management and maintenance,inspect facilities and equipments,carefully maintain equipments in curing barn and strictly perform examination and inspection.

Comparison of Benefits of Different Tobacco Loading Methods and Matching Baking Processes in Intensive Curing Houses

[Objectives]To compare the benefits of different tobacco loading methods and supporting baking processes in intensive curing houses.[Methods]Flue-cured tobacco variety K326 was taken as material,and comparative experiment on baking effects of six tobacco loading methods(traditional hanging pole,loose leaf stacking,loose leaf binding and inserting,loose leaf inserting,loose leaf net basket,loose leaf grid)was conducted.[Results]Cost of dry tobacco loading equipment for hanging pole and loose leaf stacking was 0.01 and 0.1 yuan/kg,and cost of tobacco loading by loose leaf basket reached 0.36 yuan/kg.Labor cost for baking dry tobacco by direct stacking of loose leaves reached 2.02 yuan/kg,which was the lowest,while labor cost for binding and inserting loose leaves reached 2.44 yuan/kg,which was the highest.Energy consumption cost of dry tobacco baking with loose leaf grid was 1.06 yuan/kg,which was the lowest,while baking energy consumption cost of loose leaf stacking reached 1.23 yuan/kg,which was the highest.From the perspective of baking income,loose leaf inserting reached 21.36 yuan/kg,which was the lowest,while net basket reached 27.79 yuan/kg,which was the highest,followed by grid(23.46 yuan/kg)and loose leaf binding and inserting(22.5 yuan/kg).[Conclusions]It is worth popularizing the loose leaf binding and inserting and the loose leaf grid baking.

Nitrogen Metabolism and Curing Characteristics of Flue-cured Tobacco Variety NC71

[Objectives]To explore the growth characteristics,nitrogen metabolism and curing characteristics of the new variety NC71 in strongly aromatic tobacco leaves production area.[Methods]With Yunyan 87 as the control and NC71 as the experimental material,the experiment was carried out in Nanyang tobacco area for two consecutive years to study the growth characteristics of tobacco plants,the activity of key enzymes in nitrogen metabolism,the content of secondary metabolites,and the differences of tobacco-related water content,PPO enzyme activity and total phenol content.[Results]NC71 plants had lower height,better appearance quality and lower nicotine,total sugar and chlorine content.NC71 high nitrogen treatment and Yunyan 87 medium nitrogen treatment had similar key enzyme activity of nitrogen metabolism,content of secondary metabolites;Yunyan 87 and NC71 were easy to cure and resistant to curing.[Conclusions]This study provides a reference for measuring the appropriate nitrogen application rate and optimizing the curing process from the activities of the key enzymes NR and GS in nitrogen metabolism at the mature stage of the variety.

Traveling wave solutions for a discrete diffusive epidemic model with asymptomatic carriers

This paper mainly concerns about the traveling wave solution(TwS)for a discrete diffusive epidemic model with asymptomatic carriers.Analysis of the model shows that the minimum wave speed c*exists if a threshold is greater than one.With the help of sub-and super-solutions,we find that the condition for the existence of TWS is R>1 and wave speed c>c^(*).Further,we prove that the TwS connects two different boundary steady states.Through the arguments with Laplace transform,we show there is no TWS for the model if R>1 and o<c<c^(*)or R≤1.

Dynamics of an SIRS model with age structure and two delays

ln this paper,we propose and investigate an SlRS model with age structure and twodelays.Both the infected and the recovered individuals have age structure,the infectionrate(from the infective to the susceptible)and the immune loss rate(from the recoveredto the susceptible)are related to two independent time delays,respectively.We provethat the proposed age structured SIRS model is well-posed by using the Co-semigrouptheory.The basic reproduction number Ro is given,and the unique endemic equilib-rium exists when R_(0)>1,while the disease-free equilibrium always exists.A rigorousmathematical analysis for the stability of two equilibria is provided.The disease-freeequilibrium is local asymptotically stable if R_(0)<1,and the endemic equilibrium is localasymptotically stable if R_(0)>1 and τl=0.Finally,we give numerical simulations toverify our results.