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21.
The variation in the behaviour of bulk solids as a result of sudden pressure changes in the surrounding gas phase is of interest in the application of lock hoppers for transfer of bulk solids into pressure vessels. By using such sluice systems, problems occur due to consolidation of the pressurized bulk solids. This paper presents the results of experimental and theoretical research, which allow to describe the influence of several parameters on pressure compensation and the degree of consolidation. With reference to the forces and mechanisms responsible for consolidation, it is possible to describe the different consolidation behaviour of incompressible (limestone) and compressible (hard coal) bulk solids. 相似文献
22.
Krieshok Thomas S.; Arnold John J.; Kuperman Bernard D.; Schmitz Nancy K. 《Canadian Metallurgical Quarterly》1988,35(2):211
We respond to Cochran's critique of our 1986 study, which was in part a replication of Cochran's original grid methodology for the study of career values. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
An algorithm is presented for computing degrees of sequence conservation found among aligned amino acid sequences. Sequence identities are calculated for each position of an alignment and average identity values of neighboring positions are figured. The average identity value of the whole alignment is chosen as a limit to discriminate between well and less conserved sequence sections. A second algorithm is given to calculate the degree of divergence of individual sequences compared to the other sequences of the alignment. The approach is easy to use on microcomputers and gives an exact picture of sequence identities and differences in order to determine, first, protein regions of high functional or structural importance among homologous proteins, and, second, significant differences of single sequences that may contribute to individual properties of the analysed protein. The method is illustrated by an example analysing a sequence alignment of higher plant nitrate reductases. 相似文献
24.
S Nielsen A Schmitz RE Knudsen J Dollerup CE Mogensen 《Canadian Metallurgical Quarterly》1994,87(12):747-754
In a double-blind, double-dummy, randomized, multi-centre study, the effects of bendroflumethiazide vs. enalapril on blood pressure, glycaemic control, lipoprotein concentrations and albuminuria were compared in non-proteinuric, hypertensive type 2 diabetic patients; they were treated for 20 weeks with either bendroflumethiazide 2.5-5.0 mg (n = 59) or enalapril 10-20 mg (n = 55). Age, fasting plasma glucose, HbA1c and BMI were similar in the groups. Systolic and diastolic blood pressure were reduced in both groups. Bendroflumethiazide was accompanied by minor but significant elevations in fasting plasma glucose and serum C-peptide. HbA1c was increased during both treatments. Lipoproteins and urinary albumin/creatinine ratio were stable. Bendroflumethiazide caused a decrease in serum potassium and an increase in serum urate. No significant correlations were observed between the decline in blood pressure and changes in the metabolic risk factors. Baseline levels of age, sex, BMI, blood pressure or urinary albumin/creatinine ratio were not related to changes in blood pressure, metabolic parameters or urinary albumin/creatinine ratio. 相似文献
25.
M. Erbe R. L. van Dyck-Erbe H. J. Schmitz 《Journal of materials science. Materials in medicine》1996,7(8):517-522
Polymethylmethacrylate (PMMA) bone cements present various problems with respect to biocompatibility and stability. In order to study the histological changes at the bone-cement interface following total hip replacement, a small animal model was created by implanting hip prostheses using two different bone cements (PMMA and glass-ionomer cement, GIC). Two problems with the use of GIC for fixation of the prosthesis became evident. One year following implantation, histomorphometric analysis of femurs containing the GIC demonstrated significantly higher amounts of osteoid at the bone-cement interface. This disturbance of mineralization is comparable with osteomalacia and probably due to leaching of aluminum ions. In addition the mechanical properties of GIC proved to be inadequate for the loads placed upon it in this hip replacement model. 相似文献
26.
Process development and accurate low‐cost characterization for OLED sealants by using a calcium test
Steffen Hergert Max Linkor Markus Korny Norbert Fruehauf 《Journal of the Society for Information Display》2007,15(6):421-429
Abstract— A calcium measurement setup was built for testing encapsulation especially for OLED applications. This setup is able to measure both reflective and transmissive cells. For the characterization of sealants, a method to compare them with other sealing products will be described. This includes the use of spacers, a homogeneous surface energy, and the geometry of the sealant line. The effects of different geometries will be discussed. The setup was designed to achieve good accuracy at a very reasonable component cost, which will allow other facilities to replicate this setup. Therefore, the construction plan as well as the list of components can be downloaded from our website (Ref. 3). 相似文献
27.
Norbert J. Kubilus 《Information Systems Management》1991,8(2):54-61
For many companies, involvement in mergers or acquisitions is quite common, Unfortunately, what is not so common is the IS department's role in preparing for the organizational changes that occur after a merger or acquisition has taken place. This article identifies some of the corporate issues and problems the IS department faces following a merger or acquisition and discusses how IS managers can best prepare for and manage the impact of such transactions on their IS departments. 相似文献
28.
U Vahlensieck P Bokník J Knapp B Linck FU Müller J Neumann S Herzig H Schlüter W Zidek MC Deng HH Scheld W Schmitz 《Canadian Metallurgical Quarterly》1996,119(5):835-844
1. Diadenosine hexaphosphate (AP6A) exerts vasoconstrictive effects. The purpose of this study was to investigate whether AP6A has any effect on cardiac function. 2. The effects of AP6A (0.1-100 microM) on cardiac contractility and frequency were studied in guinea-pig and human isolated cardiac preparations. Furthermore, the effects of AP6A on the amplitude of the L-type calcium current, on the adenosine 3':5'-cyclic monophosphate (cyclic AMP) content and on the phosphorylation of regulatory phosphoproteins, i.e. phospholamban and troponin inhibitor, were investigated in guinea-pig isolated ventricular myocytes. 3. In isolated spontaneously beating right atria of the guinea-pig AP6A exerted a negative chronotropic effect and reduced the rate of contraction maximally by 35% (IC20 = 35 microM). 4. In isolated electrically driven left atria of the guinea-pig AP6A exerted a negative inotropic effect and reduced force of contraction maximally by 23% (IC20 = 70 microM). 5. In isolated electrically driven papillary muscles of the guinea-pig AP6A alone was ineffective, but attenuated isoprenaline-stimulated force of contraction maximally by 23% (IC20 = 60 microM). Furthermore, AP6A attenuated the relaxant effect of isoprenaline. 6. In human isolated electrically driven ventricular preparations AP6A alone was ineffective, but attenuated isoprenaline-stimulated force of contraction by maximally 42% (IC20 = 18 microM). Moreover, AP6A attenuated the relaxant effect of isoprenaline. 7. All these effects of AP6A were abolished by the selective A1-adenosine receptor antagonist 1,3-dipropyl-cyclopentyl-xanthine (DPCPX, 0.3 microM), whereas the M-cholinoceptor antagonist atropine (10 microM) and the P2-purinoceptor antagonist suramin (300 microM) failed to abolish the effects of AP6A. 8. AP6A 100 microM had no effect on the amplitude of the L-type calcium current, but attenuated isoprenaline-stimulated L-type calcium current. The maximum of the current-voltage relationship (I-V curve) was shifted to the left by isoprenaline and additional application of AP6A shifted the I-V curve back to the right to the control value. The phosphorylation state of phospholamban and the troponin inhibitor was unchanged by AP6A alone, but was markedly attenuated by AP6A in the presence of isoprenaline. Cyclic AMP levels remained unchanged by AP6A, even after stimulation with isoprenaline. 9. In summary, AP6A exerts negative chronotropic and inotropic effects in guinea-pig and human cardiac preparations. These effects are mediated via A1-adenosine receptors as all effects were sensitive to the selective A1-adenosine receptor antagonist DPCPX. Furthermore, the effects of AP6A on cyclic AMP levels, protein phosphorylation and the L-type calcium current are in accordance with stimulation of A1-adenosine receptors. 相似文献
29.
Mycobacterium simiae was the third most common mycobacterium identified over a 2-year period from a single clinical laboratory in southern Arizona. Thirty-three isolates from 25 patients were identified over 1 year. The isolation of M. simiae was considered clinically significant for only two of 23 evaluable patients. None of five patients with human immunodeficiency virus infection had clinical disease associated with M. simiae. Twenty isolates were available for detailed study. All but one of the 20 isolates were niacin-negative, and 11 were nonphotochromogenic. All 20 isolates had a triple-cluster pattern consistent with M. simiae by high-performance liquid chromatography, and restriction fragment patterns were identical for 16 isolates. Analysis of 16S rDNA confirmed the identity of all the tested isolates as M. simiae. In this study, M. simiae was a frequent clinical isolate but was rarely associated with disease. The organisms isolated were confirmed to be M. simiae but appeared to be phenotypically distinct strains of low virulence. 相似文献
30.
Water vapour is soluted in liquid CaO-Al2O3-slags as OH?-ion. To determine the diffusion coefficient a capillary technique is used. Roughly 5 cm long platinum capillaries filled with liquid slag are equilibrated at 1500 and 1600 °C and bar different times and then are quenched in liquid D2O. By dividing these capillaries into roughly 3 mm long segments enough sample substance is won to obtain FT-IR spectra of the OH-band. From measurement of the integral extinction of the OH-band and OH?-concentration profile through the capillary is obtained. FT-IR-spectroscopy is very suitable for this capillary technique because it needs only very little sample substance. 相似文献