Obtaining cyclopentanone from acidic wastewater of caprolactam production

It has been shown that adipic acid released from the by-products of caprolactam production is a promising raw material for the production of cyclopentanone. The thermal stability of calcium adipate was investigated by the derivatographic method and the conditions were selected that ensure the yield of at least 50% of the target cyclopentanone with a purity of at least 99%

Obtaining cyclopentanone in the presence of metal oxides

Received: 01.12.2021. Revised: 13.12.2021. Accepted: 14.12.2021. Available online: 15.12.2021.The possibility of obtaining cyclopentanone by pyrolysis of calcium adipate at different temperatures was considered. The pyrolysis proceeded with the formation of cyclopentanone and cyclopentene. The use of metal salts and metal oxide catalysts for the dehydrogenation of lower alkanes makes it possible to increase the yields of the target products. The best results were achieved in the presence of a «K-16u» catalyst

Tensor analyzing power Ayy in deuteron inclusive breakup at large Pt and spin structure of deuteron at short internucleonic distances

The Ayy data for deuteron inclusive breakup off hydrogen and carbon at a deuteron momentum of 9.0 GeV/c and large Pt of emitted protons are presented. The large values of Ayy independent of the target mass reflect the sensitivity of the data to the deuteron spin structure. The data obtained at fixed $x$ and plotted versus Pt clearly demonstrate the dependence of the deuteron spin structure at short internucleonic distances on two variables. The data are compared with the calculations using Paris, CD-Bonn and Karmanov's deuteron wave functions.Comment: 4 pages, 2 figures, talk given at the SPIN2004 Conf., 10-16 Oct. 2004, Triest, Ital

Association of the biochemical parameters of ejaculate with the characteristics of spermatozoa

Motility is one of the most important characteristics of spermatozoa that determine their fertilization ability. Energy for cell movement is produced through glycolysis. Oxidation of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in the presence of hydrogen peroxide (10–3 mole) results in decreased sperm motility. This study investigated the impact of low hydrogen peroxide concentrations (10–4 and 10–5 mole) on GAPDH activity and sperm motility. Hydrogen peroxide in the above concentrations was shown to lead to an increase in total and active sperm motility by 11 and 19 %, respectively; and to simultaneously enhance GAPDH activity by 24 %. It may be that low hydrogen peroxidase concentrations stimulated the cellular antioxidant system. Along with altered sperm motility in another series of the investigation, the investigators determined the level of the biochemical components of ejaculate in different male genital diseases, such as varicocele and chronic prostatitis. Comparison of the sperm obtained from control donors and patients with varicocele showed a significant drop in the concentration of the enzymes aspartate aminotransferase, alanine aminotransferase, and cholinesterase. The other biochemical parameters of sperm did not substantially differ from those in the control group. The same level of biochemical parameters was also noted in the patients with chronic prostatitis. At 24 hours after incubation at room temperature, there were 24 and 33 % reductions in the concentrations of total protein and glucose, respectively. The concentration of ions in the sperm was considerably unchanged. At the same time following 24 hours, the motility of spermatozoa fell and their total and active motility was 41 and 30 % of the 100 % baseline level, respectively. The physiological role of the biochemical components of ejaculate is likely to be related to the maintained motility of spermatozoa when the latter are present in the female genital tract

Generation of electromagnetic fields of extremely high intensity by coherent summation of Cherenkov superradiance pulses

We demonstrate both theoretically and experimentally the possibility of correlating the phase of a Cherenkov superradiance (SR) pulse to the sharp edge of a current pulse, when spontaneous emission of the electron bunch edge serves as the seed for SR processes. By division of the driving voltage pulse across several parallel channels equipped with independent cathodes we can synchronize several SR sources to arrange a two-dimensional array. In the experiments carried out, coherent summation of radiation from four independent 8-mm wavelength band SR generators with peak power 600 MW results in the interference maximum of the directional diagram with an intensity that is equivalent to radiation from a single source with a power of 10 GW

Tensor Ayy and vector Ay analyzing powers in the H(d,d')X and ^{12}C(d,d')X reactons at initial deuteron momenta of 9 GeV/c in the region of baryonic resonances excitation

The angular dependence of the tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with a momentum of 9.0 GeV/c on hydrogen and carbon have been measured. The range of measurements corresponds to the baryonic resonance excitation with masses 2.2--2.6 GeV/c^2. The Ayy data being in good agreement with the previous results demonstrate an approximate $t$ scaling up to -1.5 (GeV/c)^2. The large values of A_y show a significant role of the spin-dependent part of the elementary amplitude of the NN->NN* reaction. The results of the experiment are compared with model predictions of the plane-wave impulse approximation.Comment: 7 pages, 7 figures. submitted to Yad.Fi

Structural phase transitions in the kagome lattice based materials Cs2-xRbxSnCu3F12 (x = 0, 0.5, 1.0, 1.5)

The solid solution Cs2-xRbxSnCu3F12 (x = 0, 0.5, 1.0, 1.5) has been investigated crystallographically between 100 and 300 K using synchrotron X-ray powder diffraction and, in the case of x = 0, neutron powder diffraction.Comment: 14 pages, 9 figure

Patterns of calcium oxalate monohydrate crystallization in complex biological systems

The paper presents the features of calcium oxalate crystallization in the presence of additives revealed through experimental modeling. The patterns of phase formation are shown for the Ca{2+} – C[2]O[4]{ 2–} – H[2]O and Ca{2+} – C[2]O[4]{2–} – PO[4]{3–} – H[2]O systems with the components and pH of the saline varying over a wide concentrations range. The effect of additives on crystallization of calcium oxalate monohydrate was investigated. It was found that the ionic strength and magnesium ions are inhibitors, and calcium oxalate and hydroxyapatite crystals are catalysts of calcium oxalate monohydrate crystallization. The basic calcium phosphate (apatite) was found to be most thermodynamically stable, which indicates its special role in kidney stone formation since it is found in virtually all stones

Coherent summation of emission from relativistic Cherenkov sources as a way of production of extremely high-intensity microwave pulses

For relativistic Cherenkov devices, we investigate the process of high-power microwave pulse generation with its phase correlating to the sharp edge of an e-beam current pulse. Our theoretical consideration is referred to quasi-stationary and superradiative (SR) generation regimes when spontaneous emission of the e-beam edge serves as the seed for the development of further coherent oscillations. Phase correlation of the excited microwave pulses with the characteristics of the current pulse front and/or an initial external electromagnetic pulse has been additionally confirmed by particle-in-cell simulations. Pulse-to-pulse stability of the radiation phase within several percents of the oscillation period makes it possible to arrange multichannel schemes producing mutually coherent microwave pulses. In the experiments that have been carried out, the cathodes of independent generators were powered by identical accelerating pulses from strictly synchronized voltage modulators, or by splitting the pulse from a single powerful modulator. For the 2-ns regime with the power of each Ka-band backward-wave oscillator about 100 MW, we demonstrate quadratic growth of the power density in the interference maximum of the directional diagram. In a short pulse SR regime, with the peak power of 600 MW in a single channel, for a four-channel 2-D array, we attained a 16-fold radiation intensity gain