24 resultados para Bogue family ( William Bogue, d. 1720 or 1)
em Chinese Academy of Sciences Institutional Repositories Grid Portal
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The gas permeability and permselectivity properties were investigated of polyimides, prepared from 3,3',4,4'- and 2,2',3,3'-thiaphthalic dianhydride (p-TDPA and m-TDPA, respectively), or 1,4-bis(3,4-dicarboxyphenoxy)- and 1,4-bis(2,3-dicarboxyphenoxy) benzene dianhydride (p-HQDPA and m-HQDPA, respectively), and 4,4-oxydianiline. The polyimides prepared from meta-dianhydrides, which have lower chain-segment packing density, possess higher permeability and lower permselectivity than those prepared from para-dianhydrides. Copyright (C) 1996 Elsevier Science Ltd.
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Song and Banner (2002, henceforth referred to as SB02) used a numerical wave tank (developed by Drimer and Agnon, and further refined by Segre, henceforth referred to as DAS) to study the wave breaking in the deep water, and proposed a dimensionless breaking threshold that based on the behaviour of the wave energy modulation and focusing during the evolution of the wave group. In this paper, two modified DAS models are used to further test the SB02's results, the first one (referred to MDAS1) corrected many integral calculation errors appeared in the DAS code, and the second one (referred to MDAS2) replaced the linear boundary element approximation of DAS into the cubic element on the free surface. Researches show that the results of MDAS1 are the same with those of DAS for the simulations of deep water wave breaking, but, the different values of the wavemaker amplitude, the breaking time and the maximum local average energy growth rate delta(max) for the marginal breaking cases are founded by MDAS2 and MDAS1. However, MDAS2 still satisfies the SB02' s breaking threshold. Furthermore, MDAS1 is utilized to study the marginal breaking case in the intermediate water depth when wave passes over a submerged slope, where the slope is given by 1 : 500, 1 : 300, 1 : 150 or 1 : 100. It is found that the maximum local energy density U increases significantly if the slope becomes steeper, and the delta(max) decreases weakly and increases intensively for the marginal recurrence case and marginal breaking case respectively. SB02's breaking threshold is still valid for the wave passing over a submerged slope gentler than 1 : 100 in the intermediate water depth.
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Strain energy density expressions are obtained from a field model that can qualitatively exhibit how the electrical and mechanical disturbances would affect the crack growth behavior in ferroelectric ceramics. Simplification is achieved by considering only three material constants to account for elastic, piezoelectric and dielectric effects. Cross interaction of electric field (or displacement) with mechanical stress (or strain) is identified with the piezoelectric effect; it occurs only when the pole is aligned normal to the crack. Switching of the pole axis by 90degrees and 180degrees is examined for possible connection with domain switching. Opposing crack growth behavior can be obtained when the specification of mechanical stress sigma(infinity) and electric field E-infinity or (sigma(infinity), E-infinity) is replaced by strain e and electric displacement D-infinity or (epsilon(infinity), D-infinity). Mixed conditions (sigma(infinity),D-infinity) and (epsilon(infinity),E-infinity) are also considered. In general, crack growth is found to be larger when compared to that without the application of electric disturbances. This includes both the electric field and displacement. For the eight possible boundary conditions, crack growth retardation is identified only with (E-y(infinity),sigma(y)(infinity)) for negative E-y(infinity) and (D-y(infinity), epsilon(y)(infinity)) for positive D-y(infinity) while the mechanical conditions sigma(y)(infinity) or epsilon(y)infinity are not changed. Suitable combinations of the elastic, piezoelectric and dielectric material constants could also be made to suppress crack growth. (C) 2002 Published by Elsevier Science Ltd.
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DSRVRajiAZTSRVSI1350088124611
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tPAPAI-1PAI-1,tPAPAI-1
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AAGMAMAHLLDPEFTIR 1712 cm~(-1) 1720 cm~(-1)840910cm~(-1) 1788 1712cm~(-1)AA 1712 cm~(-1)GMA 1720 cm~(-1)1738 cm~(-1)DSCLLDPELLDPE-g-AALLDPE-g-AAH_m4 H_m LLDPE LLDPE AASEMLLDPE-g-AA LLDPE-g-AA LLDPE-g-AA Zisman LLDPE-g-AA LLDPE/LLDPE-g-AA LLDPE-g-AA2.510~4 Pa LLDPEAA LLDPE AA SEM XPSAl_(2p)O_(1S) LLDPE-g-AA O_(1S) LLDPE-g-AA
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2010-11-23
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(Holboellia latifolia Wall.)(Gendarussa vulgaris Nees), , (Ribes takare D. Don), , 48 , , 1 3 ,-195%12 : K (1)hederagenin 3-O- -L-rhamnopyranosyl-(12)- -L-arabinopyranoside (2)-(3) 3-O--L-rhamnopyranosyl-(12)-[-D-glucopyranosyl-(13)]--L-arabinopyranosyl oleanolic acid 28-O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl ester (4) 3-O- -L-rhamnopyranosyl-(12)-O- - D-glucopyranosyl-(12)- -L-arabinopyranosyl oleanolic acid (5) 3-O-( -D-glucopyranosiduronic acid)-oleanolic acid 28-O- -D-glucopyranoside (6)lup-20(29)-en-3-one (7)lupeol (8)-(9)(10)(11)-(12)1 Lu-06N-04 Bre-04 GI50 0.77g/mL1.26 g/mL 1.55 g/mL, 2 N-04 GI50 2.44 g/mL295%1 13-hydroxyl gusanlung A (25), -(9)(10)-(12)(1-)(13)(14)(15)(16)(17)aurantiamide acetate (18)(19)(20)(-)-(21)gusanlung B (22) eupteleasaponins acetate (23)gusanlungA (24)E (26)(27)(28)25 (HepG2) GI50 2.08 g/mL395%22 : -(9) - (12) O-acetyloleanolic aldehyde (29),4,7,8-trimethoxy-2,3-methylenedioxydibenzofuran (30) 3', 5-dimethoxy-3, 4-methylenedioxybiphenyl (31) (32) 6,7-dimethoxy-1-methyl-3,4-dihydroquinolin-2-one (33)3'-hydroxy-5-methoxy-3,4-methylenedioxybiphenyl (34) 7-hydroxy-4,8-dimethoxy-2,3-methylenedioxydibenzofuran (35)(36)(37) 6- -4- -3- - (38) 5, 8-epidioxy-(22E,24R)-ergosta-6, 22-dien-3-ol (39)verrucofortine (40)6-methoxycalpogoniumisoflavone A (41)2-(42)(43), 3, 5--4-O--D-(44)(45)(46)(47)-5-O- -D-(48), 3031 35 30-10.2% (1.00 mg/mL); 35 17.2% (1.00mg/mL)41960 Plants Holboellia latifolia Wall and Gendarussa vulgaris Nees, are used as folkmedicine. Ribes takare D. Don belongs to the genus Ribes. The three plants have notbeen chemically studied in detail. Chemical and bioactive study of three plants led tothe isolation of 48 compounds by chromatography. Their structures were elucidatedon the basis of spectroscopic evidence or comparison with authentic samples. Amongthe 48 componds isolated one protoberberine alkaloid and three biphenyls are newones. Cytotoxic and -glucosidase inhibitory compounds had been found.1. Twelve compounds were isolated from the 95% ethanol extract of the aerial partof H. latifolia Wall. They were characterized as fellow: eleutheroside K (1),hederagenin-3-O- -L-rhamnopyranosyl-(12)- -L-arabinopyranoside (2),2-naphthyl acetic acid (3),3-O--L-rhamnopyranosyl-(12)-[-D-glucopyranosyl-(13)]--L-arabinopyranosyl oleanolic acid 28-O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl ester (4), 3-O- -L-rhamnopyranosyl-(12)-O- - D-glucopyranosyl-(12)- -L-arabinopyranosyl oleanolic acid (5),3-O-( -D-glucopyranosiduronic acid)-oleanolic acid-28-O- -D-glucopyranoside (6),lup-20(29)-en-3-one (7), lupeol (8), -sitosterol (9), oleanolic acid (10), ursolicacid (11), and -daucosterol (12). Compound 1 showed moderate cytotoxicity againstLu-06 (GI50, 0.77 g/mL), N-04 (GI50, 1.26 g/mL) and Bre0-4 (GI50=1.55 g/mL)and compound 2 showed moderate cytotoxicity against N-04 (GI50=2.44 g/mL).2. A new protoberberine alkaloid, 13-hydroxyl gusanlung A (25), was isolated fromthe aerial part of Gendarussa vulgaris Nees, together with -sitosterol (9), oleanolicacid (10), -daucosterol (12), glycerol monopalmitate (13), palmific acid (14),albendazole (15), albendazole sulphone (16), albendazole sufloxide (17), aurantiamideacetate (18), kumatakenin (19), genkwanin (20), (-)-syringaresinol (21), gusanlung B(22), eupteleasaponins acetate (23), gusanlung A (24), eleutheroside E (26),bergenin (27) and caffeic acid (28). Compound 25 showed cytotoxicity against HepG2 cells (GI50, 2.08 g/mL).3. Phytochemical study of the Ribes takare D. Don led to the isolation of three newbiphenyls, 4,7,8-trimethoxy-2,3-methylenedioxydibenzofuran (30), 3', 5-dimethoxy-3,4-methylenedioxybiphenyl (31) and 7-hydroxy-4,8-dimethoxy-2,3-methylenedioxydibenzofuran (35), along with nineteenknown compounds, -sitosterol (9), -daucosterol (12), O-acetyloleanolic aldehyde(29), betulin (32), 6,7-dimethoxy-1-methyl-3,4-dihydroquinolin-2-one (33),3'-hydroxy-5-methoxy-3, 4-methylenedioxybiphenyl (34), betulinic aldehyde (36),gallic acid (37), stigmast-4-en-6-ol-3-one (38), 5, 8-epidioxy-(22E, 24R)-ergosta-6,22-dien-3-ol (39), verrucofortine (40), 6-methoxycalpogonium isoflavone A (41),2-hydroxybenzophenone (42), betulinic acid (43), 3,5-dimethoxygallic acid-4-O- -D-glucopryranoside (44), apigenin (45), acacetin (46), salicylic acid (47) andapigenin-5-O- -D-glucopryranoside (48). -Glucosidase inhibitory rates ofcompound 30 and 35 were respectively 10.2% and 17.2% at a concentration of 1.00 mg/mL).4. Pharmacological activities of protoberberines were summarized.
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1 4 d6~8 d8 d85% 2 1/100, 000 3 pH 4 5 DGGE16S rDNARubritepidaRubritepidaDGGE16S rDNA 6 (1) (2) (Microcystis aeruginosa 905, zc)(Microcystis spp., zd)zczdzc Cyanobacterial blooms break out frequently all over the world, especially in developing countries. Blooms create enormous disasters to public health and to the environment. Some cyanobacterial blooms produce extremely toxic substances that have killed fish, domestic animals and birds. It has been well known that microcystins, a hepatoxin produced by Microcystis, can promote tumors in humans. So it is very important to find an effective method for controlling the growth of the bloom-forming algae. Measures for controlling such kind of algae include physical, chemic and biologic means, but the former two may damage the aquatic environment and require high-energy inputs. The alternative approach for the elimination of nuisance algae involves the application of algicidal bacteria. The algicidal bacteria, which are nontoxic to other organisms and most of which are isolated from the eutrophic lake in situ, may be potential microbial algaecides. In the initial stages of the water blooms, they are able to restrain the biomass or multiplication of the bloom-forming algae in a short time. In order to use algicidal bacteria to suppress blooms of M. aeruginosa, we isolated a bacterial culture capable of lysing the noxious cyanobacteria M. aeruginosa. In this paper we described some properties of the bacterial culture and its growth-inhibiting or algicidal effects on the growth of M. aeruginosa, and investigated its algicidal mechanisms. 1 Enrichment of a microbial culture that lyses Microcystis aeruginosa A mixed bacterial culture was isolated from a hypereutrophic pond and showed significant algicidal activity against the noxious Microcystis aeruginosa. Algae lysis would be seen obviously 4 days later when the algae culture was killed and became yellow contrast to no-addition controls, and chlorophyll a (chl-a) reduction went beyond 85% 8 days later. 2 The host range and some other algicidal feature of the mixed algicidal culture. Microcystis aeruginosa, Nostoc sp., were susceptible to the mixed algicidal culture, while the lytic effects of this mixed culture on Microcystis flos-aquae and some other tested Microcystis were feeble.The algicidal culture can not only lyse M. aeruginosa in liquid media, but aslo lyse M. aeruginosa lawns on soft agar plates and form plaques. The maximun dilution of the mixed culture required for rapid Microcystis lysis is 1/100, 000. 3 Influences of environmental factors such as pH, temperature, illumination, and the nitrogen source on the lytic activity of the mixed bacterial culture on Microcystis aeruginosa. In our investigations, it was shown that the lytic activity of the mixed bacterial culture on Microcystis aeruginosa was straightly correlated with pH, temperature, illumination, as well as the nitrogen source in the medium. The impacts of these environmental factors on the algicidal activity of the mixed bacterial culture, to a certain extent, may depend on both the algal and the bacterial growth rates under the tested environmental conditions. 4 The mechanisms of algal cell lysis by the algicidal bacteria Death was detected when the mixed bacterial culture was added to the algal culture, but not when only the culture filtrate or autoclaved bacterial culture was added. This indicates that the mixed bacterial culture did not release extracellular products inhibitory to Microcystis aeruginosa. In addition, under the microscope, we observed frequent contacts btween bacteria and algae cells, and some bacteria can even penetrate into target algal cells and destroyed them. These results may suggest that the bacterium kill the alga by direct contact. 5 Molecular Characterization of the algicidal bacterial culture Attempts for isolation of pure bacterium or bacteria from the enrichment culture responsible for Microcystis lysis have so far been failed. Based on PCR-DGGE (denaturing gradient gel electrophoresis) and 16S rDNA clone library analysis, Rubritepida sp., Pseudomonas sp. and Sphingomonas sp., as accompanying bacteria, were existed in M. aeruginosa. The bacterial community in M. aeruginosa showed significant change after adding the enrichment culture, where uncultured Flavorbacterium sp., Sphingomonas sp. and Hydrogenophaga sp. were observed, and the uncultured Flavorbacterium sp. became a dominant species. The obvious correlation can be seen between change of bacterial population and extinction of M. aeruginosa. Compared identification of pure bacterium with sequencing of DGGE bands and the clone distribution of the clone libraries, it was inferred that some uncultured bacteria were probably play an important role in controlling the growth and abundance of M. aeruginosa. This report is the first example of a mixed bacterial culture with the ability to lyse M. aeruginosa. 6 Further study for algae control by applications of algicidal bacteria (1) Algae lysis would be seen obviously 6 days later when the algae culture was killed and became yellow contrast to no-addition controls, and chlorophyll a (chl-a) was reducted to a low level 20 days later in the simulated water bloom experiments. (2) The growth of Microcystis sp. (zd) was restrained by Microcystis aeruginosa 905 (zc) when they were co-cultured together, and zc was lysed by the algicidal bacterial culture. This report is the first example of a mixed bacterial culture with the ability to lyse M. aeruginosa, and its algicidal activity remained high against non-axenic tested M. aeruginosa, suggesting that bacteria in the natural environment could play a role in controlling the growth and abundance of M. aeruginosa and other cyanobacteria. Such bacteria could also potentially be used as agents to prevent the mass development of cyanobacteria in eutrophic lakes and reservoirs.
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Spectra for Delta n = 0 transitions of the type 2s(2)2p(k)-2s2p(k+1) or 2s2p(k)-2p(k+1) from highly ionized sulfur produced in beam-foil excitation are investigated and compared to similar spectra measured with other types of light sources. In the experiment, fifty lines have been identified, of which eleven lines are new and accurately measured. Analysis of spectra was based on comparisons with other experimental results and calculated values.
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0.40.81.16A GeVNi+NiPb+Pb(GSI)FOPIFOPIFOPI(Z=1)PDTPDTAP1/3+AT1/30.41.2A GeVPDTIQMDPDTV1EoSPb+PbEoS210 MeVEoSNiNiIQMDEoSEoSIQMDPDT(A+1)/2IQMDFOPIMMRPC(0.1 kHz/cm2)MMRPC75 ps9835 kHz/cm2110 ps75DCDC
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BACKGROUND: Blocked isocyanate-functionalized polyolefins have great potential for use in semicrystalline polymer blends to obtain toughened polymers. In this study, poly(butylene terephthalate) (PBT) was blended with allyl N-[2-methyl-4-(2-oxohexahydroazepine-1 -carboxamido)phenyl] carbamate-functionalized poly(ethylene octene) (POE-g-AMPC).RESULTS: New peaks at 2272 and 1720 cm(-1), corresponding to the stretching vibrations of NCO and the carbonyl of NH-CO-N, respectively, in AMPC, appeared in the infrared spectrum of POE-g-AMPC. Both rheological and X-ray photoelectron spectroscopy results indicated a new copolymer was formed in the reactive blends. Compared to uncompatibilized PBT/POE blends, smaller dispersed particle sizes with narrower distribution were found in the compatibilized PBT/POE-g-AMPC blends. There was a marked increase in impact strength by about 10-fold over that of PBT/POE blends with the same rubber content and almost 30-fold higher than that of pure PBT when the POE-g-AMPC content was 25 wt%.
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Bond distances, vibrational frequencies, electron affinities, ionization potentials, dissociation energies and dipole moments of the title molecules in neutral, positively and negatively charged ions were studied by use of density functional method. Ground electronic state was assigned for each molecule. The bonding patterns were analyzed and compared with both the available data and across the series. It was found that besides ionic component, covalent bonds are formed between the metal s, d and f orbitals and oxygen p orbitals. Contrary to the well known lanthanide contraction, the bond distance is not regular from LaO to LuO for both neutral and charged molecules. An obvious population at 5d orbital was observed through the lanthanide series. 4f electrons also participate the chemical bonding for CeO to NdO and TbO to TmO. For EuO, GdO, YbO and LuO, 4f electrons tend to be localized. The spin multiplicity is regular for neutral and charged molecules. The spin multiplicity of the charged molecules can be obtained by -1 (or +1 for TbO+, DyO+, YbO- and YbO+) compared with the corresponding neutral molecules.
