The objective of this study was to assess the energy efficiency of nitrogen fertilization in durum wheat and sorghum grains in the period 2017-2019. Bulgarian durum wheat variety Predel was studied at a stationary fertilizer trial on soil type Pellic vertisols at the Institute of Field Crops in Chirpan, Bulgaria. Grain sorghum hybrid EC Alize was investigated on the experimental field of the Agricultural University of Plovdiv, Bulgaria, on soil type Mollic Fluvisols. The crops were grown under non-irrigated conditions. The studied nitrogen rates were 0, 60, 120, 180, and 240 kg N.ha-1. In durum wheat, nitrogen was applied two times: one third at sowing, and the rest - as top dressing in the tillering stage.  In sorghum, the total nitrogen was applied as pre-sowing fertilization before sowing. The nitrogen fertilizer was applied as NH4NO3. The experimental design was a randomized, complete block design with four replications with a size of experimental plots of 20 m2 for both crops. The energy efficiency of nitrogen fertilization (h) was calculated as the ratio between the received energy from additional grain yield of wheat and sorghum, respectively, and the invested energy from fertilization. It was established that energy efficiency of nitrogen fertilization depended on the nitrogen rate and hydro-thermal conditions during the vegetation period of durum wheat and sorghum. The bioenergy coefficient of durum wheat widely varied from 0.79 (N240 in 2018) to 4.44 (N60 in 2017). The average for the period, the highest value of energy efficiency of nitrogen fertilization was obtained at the low rate N60 The higher nitrogen rate of 240 kg N.ha-1 was slightly effective. Under drought conditions during the vegetation period of sorghum, most effective was the application of rates N120 with the highest energy coefficient ​​of 1.23. The application of 180 kg N.ha-1 to sorghum was the most energy efficient under the favorable hydro-thermal conditions in 2018 and 2019, and the average for the period 2017-2019. A low N60 rate in grain sorghum was inefficient from an energy point of view. Durum wheat showed higher energy efficiency of nitrogen fertilization compared to grain sorghum.

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Accumulation and reutilization of dry mass until anthesis and during a grain fillingperiod of sorghum in response to nitrogen fertilization in rates 0, 60, 120, 180, 240and 300 kg N.ha-1 was studied in a field experiment. Grain sorghum hybrid ECAlize was grown under not- irrigated conditions in the experimental field ofAgricultural University of Plovdiv, Bulgaria. The experimental design was arandomized, complete block design with four replications with a size ofexperimental plots of 20 m2 after wheat as predecessor. Standard farming practicesfor the region of Southern Bulgaria were applied. It was established that nitrogenfertilization significantly increased the amount of accumulated dry mass at anthesisand total above ground dry mass at maturity compared to N0. Not significant effectof higher rates (180, 240 and 300 kg N.ha-1) on the dry mass accumulation ofsorghum was found. Average post anthesis net dry mass accumulation was 3291kg.ha-1 and its amount increased in parallel with the nitrogen rate up to N180. Thehighest dry mass translocation, translocation efficiency, and contribution of preanthesisassimilations of the grain was established at nitrogen rate N120 with values2073 kg.ha-1, 25.0 % and 41,8 %, respectively. Growth of sorghum at highernitrogen rates N180, N240, N300 significantly decreased efficiency of dry masstranslocation and contribution of pre-anthesis assimilations of the grain. Nitrogenfertilization had very strong negative correlation with dry mass translocationefficiency (-0.860*) and contribution of pre-anthesis assimilations of the grain (-0.863*). Very strong positive correlation (0.988**) was found between dry masstranslocation efficiency and contribution of pre-anthesis assimilations of the grain.

Die Metallierung des Phosphorylacetons mit Koder Li in Benzol oder mit K‐ oder Li‐amid bzw. Ca in flüssigem Ammoniak liefert entsprechende Acetonato‐Komplex IR‐ und NMR‐spektroskopische Untersuchungen zeigen, daß die kristallinen Kompl xe die Chelat‐Struktur (I) besitzen, während in Lösung eine metallotrope Umlageru der cis‐Enolat‐Form (I) in die organometallische Form (II) und möglicherweise in d trans‐Enolat‐Form (III) erfolgt.

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