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In the first half of the paper, various types of processing pertaining to a polygon, using the 4×4 determinant theories are explained along with a new containment test algorithm of a point in a polygon. In the latter half of the paper, a general-purpose geometric processor, the POLYGON ENGINE, is presented which can deal with various types of interference problems, such as Boolean operations in solid modelling, hidden line and surface eliminations, ray tracing and so on. It is, a successor of the TRIANGLE PROCESSOR and is also based upon the 4×4 determinant theories [4–6]. While the TRIANGLE PROCESSOR processes a triangulated polygon on a triangle-by-triangle basis, the POLYGON ENGINE can treat a polygon without triangulation. The latter is expected to be more functional, more efficient and easier to use. 相似文献
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N,O,O′─三(对甲苯磺酰基)双(2─羟乙基)胺的合成 总被引:1,自引:0,他引:1
二乙醇胺和对甲苯磺酰氯在三乙胺存在下,反应生成N,0,O′-三(对甲苯磺酰基)双(2-羟乙基)胺,产率93%。从反应混合物中分离得副产物N,O-二(对甲苯磺酰基)双(2-羟乙基)胺。 相似文献
5.
K. Wakui K. Satoh G. Sawada K. Shiozawa K. Matano K. Suzuki T. Hayakawa Y. Yoshimura K. Murata F. Mizukami 《Catalysis Letters》2002,81(1-2):83-88
Dehydrogenative cracking reaction of n-butane was studied using HZSM-5 catalyst modified with various metal oxides. Alkaline earth (magnesium), transition metal (cobalt) and rare earth (lanthanum) elements are used for the modification. The selectivity of the products was studied at low conversion (20%). Methane, ethane, ethylene, propylene, butenes and butadiene were the main products. With the use of the cobalt- or magnesium-containing HZSM-5, dehydrogenative cracking was observed and the selectivity of ethylene was much larger than that of ethane. On the other hand, the selectivity of ethylene and ethane were almost the same in the reaction using the lanthanum-containing HZSM-5. It is considered that the cobalt- and magnesium-loaded sites on HZSM-5 played an important role in the dehydrogenative cracking. 相似文献
6.
Fujio Takahashi Ernst -H. Reimerdes Henning Klostermeyer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1977,164(3):163-166
Summary In casein-containing agarose gels, pepsin and chymosin form radial diffusion zones; the diameters of these zones show rectilinear correlations with the logarithm of the enzyme concentration at constant time. The sensitivity for both enzymes is below 1 g. Addition of the inhibitor pepstatin A to these enzymes causes a reduction of the diameters of the diffusion zones, with large differences for both the enzymes. With this procedure, the pepsin/chymosin ratio in rennet preparations was assayed with an accuracy of ±5%. Identification of the inhibitors allows the determination of amounts in the namomole range. This method is a simple technique for the evaluation of proteinases and their inhibitors in screening systems.
Geldiffusion — eine einfache und empfindliche Technik für den Nachweis von Proteinaseinhibitoren und die Anwendung für die Bestimmung von Proteinasen in Gemischen
Zusammenfassung In caseinhaltigen Agarosegelen erzeugen sowohl Pepsin wie Chymosin radiale Diffusionszonen, deren Durchmesser bei gegebener Zeit dem Logarithmus der Enzymmenge proportional ist. Die Bestimmungsgrenze liegt für beide Enzyme unter 1 g. Bei Zugabe des Inhibitors Pepstatin A zu den Proteinasepräparaten werden die Diffusionszonen beider Proteinasen verkleinert, aber in unterschiedlichem Ausmaße. Auf dieser Basis kann in technischen Labpräparaten das Mengenverhältnis Pepsin/Chymosin mit einer Genauigkeit von ±5% bestimmt werden. Bei Umkehr der Reaktion zum Nachweis des Inhibitors sind Mengen im Bereich von 10–9 Mol sicher erfaßbar. Die Methodik ist verallgemeinerungsfähig als Screening-Test für Proteinaseinhibitoren.相似文献
7.
Allinson M Kageyama S Nakajima D Kamata R Shiraishi F Goto S Salzman SA Allinson G 《Water science and technology》2012,66(4):768-774
In 2007, samples of treated effluent were collected at point of discharge to the environment from 39 wastewater treatment plants (WWTPs) located across Victoria, Australia grouped by treatment type. Sample genotoxicity was assessed with a high-throughput luminescent umu test method using Salmonella typhimurium TL210 strain, with and without addition of a commercially available metabolic activation system. Samples were also screened using a gas chromatographic-mass spectrometric mass-structure database recognition method. A genotoxic response was observed in half of the samples tested without metabolic activation system (相似文献
8.
Enzymatic production of cytidine diphosphate choline (CDP-choline) using orotic acid and choline chloride as substrates was investigated using a 200-ml beaker as a reaction vessel. When Cornybacterium ammoniagenes KY13505 cells were used as the enzyme source, UMP was accumulated up to 28.6 g/liter (77.6 mM) from orotic acid after 26 h of reaction. In this reaction, UDP and UTP were also accumulated, but CTP, a direct precursor of CDP-choline, was not accumulated sufficiently. Escherichia coli JF646/pMW6 cells, which overproduce CTP synthetase by selfcloning of the pyrG gene, were used together with cells of KY12505 for the enzymatic reaction using orotic acid as a substrate. CTP was produced at 8.95 g/liter (15.1 mM) after 23 h of this reaction. To produce CDP-choline, two additional enzyme activities were needed. E. coli MM294/pUCK3 and MM294/pCC41 cells, which express a choline kinase from Saccharomyces cerevisiae (CKIase; encoded by the CKI gene) and a cholinephosphate cytidylyltransferase from S. cerevisiae (CCTase; encoded by the CCT gene) respectively, were added to this CTP-producing reaction system. After 23 h of the reaction using orotic acid and choline chloride as substrates, 7.7 g/liter (15.1 mM) of CDP-choline was accumulated without addition of ATP or phosphoribosylpyrophosphate (PRPP). ATP and PRPP required in the CDP-choline forming reaction system are biosynthesized by those cells using glucose as a substrate. 相似文献
9.
Sone T Nagamori E Ikeuchi T Mizukami A Takakura Y Kajiyama S Fukusaki E Harashima S Kobayashi A Fukui K 《Journal of Bioscience and Bioengineering》2002,94(1):87-91
We have produced micrometer-sized calcium alginate beads referred to as "bio-beads" that encapsulate plasmid DNA molecules carrying a reporter gene. In order to evaluate the efficiency of the bio-beads in mediating genetic transfection, protoplasts isolated from cultured tobacco cells (BY-2) were transfected with bio-beads containing a plasmid that carries the modified green fluorescent protein gene CaMV35S-sGFP. With the bio-beads treatment, approximately ten-fold higher GFP expression was observed after 24 h incubation compared to that with the conventional method using a naked plasmid solution. Transfection was up to 0.22% efficient. These results indicate that bio-beads have a possibility for efficient transformation in plants. 相似文献
10.
Considers the problem of robust stability of uncertain time-delay dynamical systems. A new robust stability criteria for linear dynamical systems subject to delayed time-varying and nonlinear perturbations is derived. The results obtained in this note are less conservative than the ones reported so far in the literature. Some analytical methods are employed to investigate the bound on the perturbations so that the systems are stable. A numerical example is given to demonstrate the utilization of the authors' results 相似文献