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71.
Peter Zimmermann 《Concurrency and Computation》1991,3(4):399-412
Visual simulation is one of the most important parts of a driving simulator. Unfortunately it is in general the most expensive part too. CGI-manufacturers tend to develop more complex systems because of the demands of the military market. The common systems are strongly hardware-oriented. On the basis of a new type of microprocessor, the transputer, a more software-oriented approach is introduced. Transputers in connection with the new high-level language occam are well suited for pipelining and parallelization owing to their communication concept. The advantages of this approach are reduced costs and development time, and also the capability for fast and cheap changes in algorithms. The achievable performance meets the requirements for a driving simulator very well. 相似文献
72.
Pyrylium Compounds. 45. 4-Aroyl-fluorenes from 2,4,6-Triaryl-pyrylium Salts and Indan-1-one via 2-(5-Oxo-pent-2-en-1-yliden)-indan-1-ones 2,4,6-Triarylpyrylium salts 1 react with indan-1-one in the presence of an appropriate buffer system (e.g. piperidine acetate, triethylamine/acetic acid, triethylamine or sodium acetate) to yield the 2-(1,3,5-triaryl-5-oxo-pent-2-en-1-yliden)-indan-1-ones 2 . For the reaction medium aliphatic alcohols (methanol, ethanol), dipolar aprotic solvents (acetonitrile) or chlorinated hydrocarbons (methylene chloride, chloroform, carbon tetrachloride) can be used. On treating 2 with sodium methanolate in methanol, a cyclization reaction occurs giving rise to the 4-aroyl-1,3-diaryl-fluorenes 3 . As by-products 1,3-diaryl-fluorenes 8 (e.g. 1,3-diphenyl-fluorene) are formed. - I.r., n.m.r. and u.v. spectroscopic data of the novel compounds 2 and 3 are reported. 相似文献
73.
74.
T. Zimmermann G. W. Fischer J. Teller H. Dehne B. Olk 《Advanced Synthesis \u0026amp; Catalysis》1990,332(5):723-730
Substituted N,N′-Bis(thiazol-2-yl)-diaminoalkanes from α-Thiocyanato-acetophenones and N,N′-Dialkyl-diaminoalkanes α-Thiocyanato-acetophenones 1 react with N,N′-dialkyl-diaminoalkanes 2 in the presence of an appropriate weak acid (acetic acid, propionic acid, benzoic acid) to give the hitherto unknown N,N′-dialkyl-N,N′-bis(4-aryl-thiazol-2-yl)-diaminoalkanes 3 . As reaction medium aliphatic alcohols (ethanol, methanol), halogenated hydrocarbons (methylene chloride, chloroform, carbon tetrachloride) or dipolar-aprotic solvents (acetonitrile, dimethylformamide) can be used. - I.r., u.v., n.m.r. and mass spectroscopic data of the novel bisthiazoles 3 are reported. 相似文献
75.
Marie Ebeyer-Masotta Tanja Eichhorn Ren Weiss Vladislav Semak Lucia Laukov Michael B. Fischer Viktoria Weber 《International journal of molecular sciences》2022,23(3)
Inflammation and thrombosis are closely intertwined in numerous disorders, including ischemic events and sepsis, as well as coronavirus disease 2019 (COVID-19). Thrombotic complications are markers of disease severity in both sepsis and COVID-19 and are associated with multiorgan failure and increased mortality. Immunothrombosis is driven by the complement/tissue factor/neutrophil axis, as well as by activated platelets, which can trigger the release of neutrophil extracellular traps (NETs) and release further effectors of immunothrombosis, including platelet factor 4 (PF4/CXCL4) and high-mobility box 1 protein (HMGB1). Many of the central effectors of deregulated immunothrombosis, including activated platelets and platelet-derived extracellular vesicles (pEVs) expressing PF4, soluble PF4, HMGB1, histones, as well as histone-decorated NETs, are positively charged and thus bind to heparin. Here, we provide evidence that adsorbents functionalized with endpoint-attached heparin efficiently deplete activated platelets, pEVs, PF4, HMGB1 and histones/nucleosomes. We propose that this elimination of central effectors of immunothrombosis, rather than direct binding of pathogens, could be of clinical relevance for mitigating thrombotic complications in sepsis or COVID-19 using heparin-functionalized adsorbents. 相似文献
76.
T. Zimmermann G. W. Fischer B. Olk M. Findeisen 《Advanced Synthesis \u0026amp; Catalysis》1989,331(2):306-318
Pyrylium Compounds. 42. Benzocycloalkenones and Dihydro-2H,7H-1-benzopyranones from 2,4,6-Triarylpyrylium Salts and Cycloalkane-1,2-diones 2,4,6-Triarylpyrylium salts 1 react with cycloalkane-1,2-diones 2 in the presence of an appropriate condensing agent to yield benzocycloalkenones 3 . Thus, sodium acetate and cyclo-hexane-1,2-dione ( 2a ) lead to the dihydro-2H-naphthalenones 3a – i , whereas with cycloheptane-1,2-dione ( 2b ) and piperidine acetate, triethylamine or sodium acetate the tetrahydro-5H-benzo-cyclohepten-5-ones 3j – r are formed. As shown for the example 3a, j → 4a, b , benzocycloalkenones of type 3 can be converted into phthalazines 4 on heating with hydrazine in ethanol. By reaction of the dione 2a and an equimolar mixture of triethylamine and acetic acid or morpholine acetate with the salts 1 5,6-dihydro-2H,7H-1-benzopyran-8-ones 5 are obtained as a result of a new type of ring transformation. The pyrans 5 can be cleaved with perchloric acid in ethanol to 5,6,7,8-tetrahydro-8-oxo-1-benzopyrylium perchlorates 6 . If the pyrans 5 are heated with sodium acetate in ethanol, a conversion to benzocycloalkenones 3 is achieved (cf. 5a → 3a ). The structure of the new compounds was established by spectroscopic methods. 相似文献
77.
Jagadeesh Nagendra Manda Milica Markovic Prof. Ellen M. Zimmermann Prof. Shimon Ben-Shabat Prof. Arik Dahan Prof. Aaron Aponick 《ChemMedChem》2020,15(17):1639-1644
Novel phospholipid (PL)-cyclosporine conjugates were prepared and studied as potential prodrugs for inflammatory bowel disease (IBD). Our approach relies on phospholipase A2 (PLA2), which is overexpressed in the inflamed intestinal tissues, as the prodrug activator to potentially release cyclosporine at the site of inflammation. PL-cyclosporine prodrug conjugates with methylene linkers of various lengths between the sn-2 position of the PL and cyclosporine were synthesized and evaluated for in vitro activation. Surprisingly, despite previous work indicating that conjugates with six methylene linkers between the lipid and drug would suffer rapid enzymatic hydrolysis, with cyclosporine this was not observed. However, compounds with longer linkers (n=10, 12 methylene units) display complete release of the drug by PLA2-catalyzed hydrolysis, thus demonstrating the importance and profound impact of structural fine-tuning. This study represents a proof-of-concept for our hypothesis and a first step towards a truly targeted IBD treatment with cyclosporine that could be administered throughout the GI tract. 相似文献
78.
汽车钢板回收冶炼过程中涂覆油漆的裂变行为 总被引:4,自引:0,他引:4
采用单光子离子化/共振增强的多光子离子化-飞行时间质谱法(SPI/REMPI-TOFMS)研究了在汽车钢板的回收冶炼过程中,涂覆油漆的裂变行为.在模拟实验装置中,在线跟踪监测了裂解炉气中的有机裂变产物的演变过程.发现与其它有机材料不同,汽车钢板的涂覆油漆不仅在合成空气中,而且在氮气中也产生酚类有机污染物.从300 ℃到1 190 ℃都有多环芳烃(PAHs)产生,但在700~800 ℃时,产生的数量最多,在1 000~1 190 ℃,趋于完全燃烧. 相似文献
79.
James W. Zimmermann Gregory E. Hilmas William G. Fahrenholtz Ralph B. Dinwiddie Wallace D. Porter Hsin Wang 《Journal of the American Ceramic Society》2008,91(5):1405-1411
Thermophysical properties were investigated for zirconium diboride (ZrB2 ) and ZrB2 –30 vol% silicon carbide (SiC) ceramics. Thermal conductivities were calculated from measured thermal diffusivities, heat capacities, and densities. The thermal conductivity of ZrB2 increased from 56 W (m K)−1 at room temperature to 67 W (m K)−1 at 1675 K, whereas the thermal conductivity of ZrB2 –SiC decreased from 62 to 56 W (m K)−1 over the same temperature range. Electron and phonon contributions to thermal conductivity were determined using electrical resistivity measurements and were used, along with grain size models, to explain the observed trends. The results are compared with previously reported thermal conductivities for ZrB2 and ZrB2 –SiC. 相似文献
80.
Glycation of the Major Milk Allergen β‐Lactoglobulin Changes Its Allergenicity by Alterations in Cellular Uptake and Degradation 下载免费PDF全文
Marija Perusko Manon van Roest Dragana Stanic‐Vucinic Peter J. Simons Raymond H. H. Pieters Tanja Cirkovic Velickovic Joost J. Smit 《Molecular nutrition & food research》2018,62(17)