N=2 supersymmetric Yang-Mills theory and the superparticle: twistor transform and kappa-symmetry

Lagrangian and Hamiltonian dynamics of de Azcarraga-Lukierski N=2 massive superparticle is considered in the framework of twistor-like Lorentz-harmonic approach. The emphasis is on the study of the interaction with external Abelian gauge superfield. The requirement of preservation of all gauge symmetries of the free model including kappa-symmetry yields correct expressions for the superfield strength constraints and determines the form of nonminimal interaction. We also show that for de Azcarraga-Lukierski N=2 massive superparticle the pullback of field strength 2-superform to the superworld line is not integrable in contrast to the massless superparticle.Comment: 16 pages, LaTe

Effective application of mass balance method: case of organic fertiliser produced from pig slurry

Received: January 26th, 2021 ; Accepted: May 8th, 2021 ; Published: May 11th, 2021 ; Correspondence: [email protected] study aimed to verify the applicability of the mass balance method in calculating quantity and quality of an organic fertiliser produced from unseparated pig slurry in a pigfattening complex in the Leningrad Region. The amount of manure at ex-animal level and its nutrient content, required for further calculations of ex-housing manure and resulting organic fertiliser at ex-storage, were calculated by applied diets and feed DM digestibility. Calculated values were compared with the norms from relevant Russian regulatory documents. The regulatory values of manure nitrogen were 22% smaller than the calculated ones. On the contrary, the standard values of manure phosphorus and potassium exceeded the calculated ones by 72% and 73%, respectively. The nutrient content of the organic fertiliser was calculated by the farm data on pig housing and slurry processing systems. The values calculated by the mass balance method were compared with those from the analysis reports issued by the certified laboratory. The difference did not exceed 20%: 11.2% for N, 13.3% for P, and 18.7% for K. This way, the mass balance method can be effectively used for calculating the characteristics of pig slurry-based organic fertiliser. On the contrary, the data from the current regulatory manure management documents showed the low reliability in the part of the physicochemical properties of fattening pig manure. These documents do not take into account the changes in the fattening pig diets with modern special concentrated feeds, which have a major effect on the manure nutrient content

Aerobic solid-state fermentation of the solid fraction of pig slurry

Current expansion in the pig number in Russia and their concentration in separate locations contribute to higher environmental risks. One key risk factor is the slurry produced. To utilize it more efficiently, many pig farms introduce its solid-liquid separation. The study objective was to explore the feasibility of accelerated aerobic solid-state fermentation of the solid fraction of pig slurry in closed installations. The stable thermophilic process under the temperature above +55 °C achieves shorter processing time of 3–4 days. To date, however, there is no representative evidence of such an experience. Four options of fermented mixture composition were tested based on two types of the solid fraction of pig slurry: Type 1 fraction coming from a screw separator and Type 2 fraction coming from a decanter centrifuge. The fermenter operating modes were tested in the authors’ previous studies associated with processing of the solid fraction of cattle manure and bedding poultry manure. The intensity measure of fermentation was the temperature reached by the processed material in the fermenter. Under the investigated operation modes, the stable temperature was observed for nine days in the mesophilic process: 20 °С to 55 °С; in some cases, the transition to the thermophilic process – above 55 °С was recorded. Adding the catalytic components to the processed material accelerated the substrate self-heating and a higher temperature up to 59 °С was reached. This suggests that the considered operating modes of the fermenter were suitable for the fermentation of the specified substrate

AdS_4 x CP^3 superstring and D=3 N=6 superconformal symmetry

Motivated by the isomorphism between osp(4|6) superalgebra and D=3 N=6 superconformal algebra we consider the superstring action on the AdS_4 x CP^3 background parametrized by D=3 N=6 super-Poincare and CP^3 coordinates supplemented by the coordinates corresponoding to dilatation and superconformal generators. It is also discussed the relation between the degeneracy of fermionic equations of motion and the action kappa-invariance in the framework of the supercoset approach.Comment: revtex, 12 pages. Version accepted to Phys. Rev. D; v4 corrected misprints in Eqs.(65), (71); v5 corrected discussion of Z_4 grading on page

Variation in the mass and moisture content of solid organic waste originating from a pig complex during its fermentation

The focus of the study was the fermentation of an organic waste mixture originating from a pig-rearing complex. The organic waste was processed in the laboratory-scale drum fermenter. Through the fermentation process, the fermented material was weighed by a system of four strain gauges installed under the fermenter. In our previous study, the following initial mixture characteristics were justified to have the fermentation process going – 65% to 70% moisture content and 400–600 kg m-3 density. The optimal operation mode of the fermenter was identified depending on the initial mixture composition – aeration frequency of 5 min h-1 ; air consumption of 11.3 m3 h -1 per 1.7 m3 of the fermenter volume; drum rotation interval – three times every 12 hours. Under this operating mode, the mass loss was 3% already on the third fermentation day and 7% – on the fifth day. As a result, the mass of the finished organic fertiliser was 9% smaller than that of the loaded mixture. The moisture content of the processed material also decreased: under the average moisture content of the loaded mixture of 68.7%, the average moisture content of the organic fertiliser was 66.4%. Based on the resulting experimental data, the mathematical models describing the dependence of the mass and moisture content of the processed material on the fermentation time were created. The study outcomes allow concluding that the solid-state aerobic fermentation is one of the promising options for the utilisation of the solid fraction of pig slurry