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Kerosene from the hydrocracking is commonly used to produce JET fuel. Depending on the deactivation of the catalyst, the aromatic content of such kerosene increases to a level where it can no longer be used for JET fuel production. The objective of this study was to determine whether the aromatic content of kerosene from hydrocracking can be reduced under the conditions used for hydrotreating straight-run middle distillates. The kerosene obtained from a real hydrocracker unit was investigated in a laboratory fixed-bed unit packed with a Ni-Mo/Al2O3 catalyst. Aromatics content was analyzed utilizing ASTM D6379 (HPLC). As a result of the hydrogenation, the aromatic content was reduced from 22.6 to 14.5 wt.% (3 MPa) and 3.0 wt.% (6 MPa). The product contained 60–70 wt.% cycloalkanes. The smoke point was improved by 3.3 mm (3 MPa) up to 9.7 mm (6 MPa), and the cetane index by 1.1 or 3.9 units, respectively. The (H/C)at ratio in kerosene increased from 1.89 to 1.98. Furthermore, no significant cracking occurred during the hydrogenation. Overall, we demonstrate that the aromatic content of such kerosene can be very well controlled by downstream hydrogenation under conditions common in oil refineries for the desulfurization of middle distillates. [ABSTRACT FROM AUTHOR]

Dielectric resonators for a two pole filter were developed and tested. They consist of LaAlO3 single crystalline cylinders covered on the cylindrical surface by 4 micrometer gold films and on the end faces by 350 nm YBa2cu3O7-delta thin films. The two-pole bandpass filters fabricated from the resonators have an insertion loss of -0.26 dB at their center frequencies of 6.3 GHz at 77 K.

We prepared and tested dielectric resonators designed for a two pole filter. These resonators were LaAlO/sub 3/ single crystalline cylinders which were covered on the end faces by about 350 nm YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// thin films and on the cylindrical surface by 4 /spl mu/m gold films. The YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// films were c-axis oriented with mosaic spreads of about 0.3/spl deg/. The inductive transition temperatures were above 90 K. The HF properties were characterized by evaluation of the H/sub 011/ mode at 8.05 GHz, and by measuring the surface resistance at 18.9 GHz. At 77 K the Q-value of this resonance was typically 12000, which is about a factor of 2 higher than the Q-value of 6560 found for end faces covered with pure copper. From these resonators two-pole bandpass filters were constructed that at 77 K showed an insertion loss of -0.26 dB at their center frequency of 6.3 GHz. [ABSTRACT FROM PUBLISHER]

Neutrophil serine proteases (NSPs) in cytoplasmic granules of neutrophils are regarded as important antimicrobial defense weapons after engulfment and exposure of pathogens to the content of primary granules. Despite intensive studies on neutrophils during the last three decades, only three active serine proteases, neutrophil elastase (NE), cathepsin G (CG), and proteinase 3 (PR3) have been identified in these short-lived cells. Here, we report on the identification of a fourth serine protease (NSP4) with 39% identity to NE and PR3, but arginine specificity, yet sharing features like propeptide processing by dipeptidyl peptidase I, storage, and release as an active enzyme with the three active proteases. We established monoclonal antibodies against NSP4, excluded cross-reactivity to human granzymes, NE, CG, PR3, and azurocidin, and screened for NSP4 protein expression in various human tissues and blood leukocyte populations. Only granulocyte precursors and neutrophil populations from peripheral blood were positive. The content of NSP4 in neutrophil lysates, however, was about 20-fold lower compared with CG. Upon neutrophil activation, NSP4 was released into the supernatant. Profiling its specificity with peptide libraries from Escherichia coli revealed a preference for arginine in P1; it cleaved Tyr-Arg-Phe-Arg-AMC and Ala-Pro-Nva-thiobenzyl esters. NSP4 was inhibited by α(1)-proteinase inhibitor (α(1)-antitrypsin), C1 inhibitor, and most efficiently by antithrombin-heparin, but not by elafin, secretory leukocyte protease inhibitor, α(1)-antichymotrypsin, and monocyte-neutrophil elastase inhibitor. Functional specialization and preferred natural substrates of NSP4 remain to be determined to understand the biological interplay of all four NSPs during neutrophil responses.

3 years experience in corticoid treatment of more than 796 cases of rhinoplasty is reported. A remarkable reduction of oedema after surgery was observed. The application of 40 mg Corticoid crystalline suspension on each side of the nose following surgical procedure is recommended.

In two groups, each of 40 patients, with previously untreated cavernous pulmonary tuberculosis the following treatment schemes were compared in a randomised clinical study: isoniazid, ethambutol, and rifampicin (control group) and isoprodian with rifampicin (study group). Bacteriologic and radiographic parameters showed that in the study group the results were at least as good as in the control group. Symptoms of drug intolerance were equally rare in both groups.