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1.
SCOT capillary Chromatographic and SCOT capillary chromatographic-mass spectrometic analyses of gland washes and effluvia of virgin femaleChoristoneura occidentalis Free, have been conducted with both a diapausing and nondiapausing strain of this insect. The following compounds were identified in gland washes and effluvia in both strains:E andZ11–14Ald,E andZ11–14Ac,E andZ11–14OH and 14Ald, 14Ac, and 14OH. The average aldehyde: acetate: alcohol ratio found by analysis of single glands by virgin females (nondiapausing strain) was 170.73. Analysis of virgin female effluvia gave this ratio as 1038 (diapausing strain: %Z=8, 11, 15, respectively) and 1036 (nondiapausing strain: %Z=8, 11, 12, respectively). The saturated components were generally 1–2% of theE isomer in each case. Comparisons of EAG responses of bothC. occidentalis andC. fumiferana toE11–14Ald,E11–14Ac andE11–14OH were made. Correlations with both laboratory and field data previously published were also made betweenC. fumiferana andC. occidentalis.Lepidoptera: Tortricidae.  相似文献   

2.
Summary A series of linear side-chain aliphatic polyesters have been synthesized from -(bis(2-hydroxyethyl)amino)--(4-methoxybiphenyl-4-oxy) alkanes and aliphatic acid chlorides. The side-chain and main-chain spacer lengths were varied and their influences on thermal and structural properties of polyesters, as determined by DSC and X-ray diffraction, are discussed.  相似文献   

3.
Methylation of 4-methylbiphenyl with methanol was carried out using zeolites HY, HM, and HZSM-5 as catalysts under fixed-bed down-flow conditions. HY and HM display no shape selectivity, but HZSM-5 shows moderate selectivity to the target product, 4,4-dimethylbiphenyl (4,4-DMBP) under proper reaction conditions. Modification of the surface of HZSM-5 zeolite can improve the selectivity to 4,4-DMBP, especially the simultaneous modification of external and internal surface with inorganic P compound. The selectivity to 4,4-DMBP can be increased to as high as 65% over the HZSM-5 modified with a small amount of ammonium hydrogen phosphate.  相似文献   

4.
(E)-12-Tetradecenyl acetate (E12–14OAc), (Z)-12-tetradecenyl acetate (Z12–143nOAc), and tetradecanyl acetate (14OAc) were extracted and identified as major chemical components from female tips of the Asian corn borer,Ostrinia furnacalis (Hübner) (Lepidoptera: Pyralidae) in Taiwan, with a combined wash ratio of 483715 and an individual female ratio of 453916. The average amount ofE12-,Z12–14OAc and 14OAc in each female gland was 6.6±4.6, 5.8±3.5, and 2.4±1.7 ng/female, respectively. The mixture of these three synthetic chemicals not only gave strong activities in male antennae but also could catch significantly more males than virgin females in field-trapping tests. The field test also showed no significant difference in trapping ability among the three-component Taiwan formulations, the two-component Taiwan formulation (Z12–14OAc andZ1214OAc, 5347), and the Japan formulation (Z12–14 OAc andE 12–14OAc, 3:2).  相似文献   

5.
Copoly(methyl-3-biphenoxypropylsilylene 1,4-phenylene), copoly(methyl-3-cyanopropylsilylene 1,4-phenylene), copoly(methyl-3-ethoxypropylsilylene 1,4-phenylene), copoly(methyl-3-phenoxypropylsilylene 1,4-phenylene), and copoly(methyl-4,7,10,13-tetraoxatetradecanylsilylene 1,4-phenylene) have been prepared by platinum-catalyzed hydrosilation graft reactions between poly (methylsilylene 1,4-phenylene) and appropriate functionally substituted alkenes. These polymers have been characterized by1H,13C, and29Si NMR as well as by FT-IR and UV-vis spectroscopy. The molecular weight distribution of these polymers has been determined by gel permeation chromatography (GPC), and their glass transition temperatures (T e) by DSC.  相似文献   

6.
Summary The general equations for the radiation dose dependence of irradiated polymer molecular weights have been solved exactly. For an initial most probable molecular weight distribution (=1), the solutions are analytical and exact. For the general case (1) the solutions are numerical and exact. The present approach has resulted in the solutions for both =1 and 1 being incorporated into a group of FORTRAN computer programs which will solve experimental data for scission and crosslinking yields by both minimization and exact treatments. Simulated data treated using these FORTRAN programs are give. The FORTRAN programs are available from the authors.  相似文献   

7.
Three biphenyl unit-containing diamines,4,4-bis(p-aminophenoxy)biphenyl (IIIa), 2,2-bis(p-aminophenoxy)biphenyl (IIIb), and 3,3,5,5-tetramethyl-4,4-bis(p-aminophenoxy)biphenyl (IIIc), were prepared by the chlorodisplacement ofp-chloronitrobenzene with 4,4-biphenol (Ia), 2,2-biphenol (Ib), and 3,3,5,5-tetramethyl-4,4-biphenol (Ic), respectively, giving the corresponding bis(nitrophenoxy) compounds IIa-c, followed by catalytic reduction with palladium (Pd) and hydrazine. Three series of polyimidesp-PI,o-PI, and Me-PI were prepared from diamines IIIa-c and aromatic tetracarboxylic dianhydrides via a two-stage procedure that included ring-opening polyaddition to give poly(amic acid)s followed by thermal cyclodehydration to polyimides. The resultant three series of poly(amic acid)s had inherent viscosities of 1.09–2.83, 0.78–1.93, and 1.55–3.09 dL/g, respectively. Almost all the poly(amic acid)s could be solution-cast and thermally converted into transparent, flexible, and tough polyimide films. All the polyimides were characterized by solubility, tensile test, wide-angle X-ray scattering measurements, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Effects of the structures of aromatic diamines and dianhydrides on the properties of polyimides were investigated.  相似文献   

8.
V. Percec  S. Okita  J. Bae 《Polymer Bulletin》1992,29(3-4):271-276
Summary The synthesis and Ni(0) catalyzed homocoupling polymerization of 4,4-bis[5-(trifluoromethanesulfonyloxy)-2-biphenylyl]-1, 1-binaphthyl (9) are described. This polymerization reaction produces a soluble polyarylene containing alternating 4,4-(1,1-binaphthyl) and 4,4-(3,3-diphenyl)biphenyl structural units.  相似文献   

9.
The intertidal pulmonate limpetTrimusculus reticulatus, which is found in caves or crevices along the California coast, was previously reported to contain two novel diterpenoids, 6-isovaleroxylabda-8,13-dien-7,15-diol (1) and 2,7-diacetoxy-6-isovaleroxylabda-8,13-dien-15-ol (2). Dissection of the animals prior to extraction revealed that the diterpenoids were concentrated in the mantle, foot, and mucus, but not in the viscera. The presence ofT. reticulatus or its mucus was toxic to veliger larvae of the sabellariid reef-building tube wormPhragmatopoma californica. The major diterpenoid1 was responsible for the observed larvicidal activity. Protection against overgrowth by settling invertebrate larvae is important for the survival of this sessile filter-feeding pulmonate. A related pulmonate,T. conica, which was found in similar intertidal habitats in New Zealand, contained 6-acetoxy-7-isovaleroxylabda-8,13-dien-15-oic acid (3) and 1,7,12,18-tetraacetoxy-cholest-5-en-3-ol (4). The diterpene3 was also localized in the foot, mantle, and mucus ofT. conica but was not larvicidal toP. californica.  相似文献   

10.
The electrochemical behavior of non-alkyl substituted viologen, 4,4-dibenzyl bipyridinium (BzV), 4,4-dicyanophenyl bipyridinium (CyV) and -,-,-cyclodextrin (, , -CD) was studied using cyclic voltammetry and a spectroelectrochemical method. It was found that BzV and Fe(CN) 6 4– formed a charge-transfer (CT) complex with a ratio of 21 and the colour of the solution faded with the addition of an electrolyte. This behaviour is the same as in then-heptyl viologen and ferrocyanide system [1]. BzV, -CD and -CD formed an inclusion complex only in the reduced state, whilst BzV and -CD formed an inclusion complex in both the oxidized and the reduced state. An EC scheme in which a chemical reaction follows an electrochemical reaction was considered to predominate in the BzV and -, -CD systems, while a CE scheme in which a chemical reaction preceded an electrochemical reaction predominated in the BzV and -CD system. On the other hand, CyV was found to form an inclusion complex with -, -, -CD in both the oxidized and the reduced states. therefore a CE scheme was considered to predominate in the CyV--, -, -CD systems.  相似文献   

11.
(Z)-11-Octadecenyl acetate (Z11–18Ac) and (Z)-11-eicosenyl acetate (Z11–20Ac) were identified as the aggregation pheromones ofDrosophila ananassae, andZ11–20Ac was identified as the aggregation pheromone ofDrosophila bipectinata. Z11–18Ac andZ11–20Ac were not attractive alone; however, in combination with fermenting food odors, the acetates attracted flies of both sexes in a wind-tunnel olfactometer. The pheromones were present in the ejaculatory bulb of sexually mature male flies and transferred to the female during mating. MaleD. bipectinata released little if anyZ11–20Ac to the food; however, recently mated females releasedZ11–20Ac to the surrounding surfaces in just a few hours after mating.D. ananassae males, on the other hand, appeared to release moreZ11–18Ac andZ11–20Ac to the surroundings than mated females. AlthoughD. bipectinata males had noZ11–18Ac, flies were as attracted toZ11–18Ac as to an equal quantity ofZ11–20Ac.D. ananassae were attracted toZ11–18Ac but not toZ11–16Ac orZ11–20Ac. However,Z11–20Ac in combination withZ11–18Ac was significantly more attractive thanZ11–18Ac alone.  相似文献   

12.
Summary Poly(butadienes) were modified by an ene-reaction using 4-phenyl-1, 2,4-triazoline-3,5-dione (1) 3-nitro-4-hydroxyphenyl-1, 2,4-triazoline-3,5-dione (2) and 4-hydroxyphenyl1, 2,4-triazoline-3,5-dione (3). The resulting hydrogen bond complexes between urazole groups act as thermoreversible crosslinks and alter the melt rheological behaviour. While dimeric chelate-like complexes are formed in polymers modified with 1 or 2, a three dimensional structure of hydrogen bond complexes is formed if 3 is used as the modifying agent. The thermorheologically complex behaviour of the latter material is interpreted by structural changes in the three dimensional structure with temperature.  相似文献   

13.
Liquid phase isopropylation of biphenyl with propylene was studied over a cerium exchanged sodium mordenite (Ce/NaM25) and a H-mordenite (HM25) with the same SiO2/Al2O3 ratio of 25. Shape-selective catalysis occurred to give 4,4-diisopropylbiphenyl (4,4-DIPS) in high selectivity over Ce/NaM25 under any propylene pressures. HM25 gave 4,4-DIPS shape-selectively under high propylene pressures. However, the reaction was severely deactivated at a conversion of ca. 60% under such a low pressure as 0.8 kg/cm2 because of coke formation in the pore. The yields of 4-isopropylbiphenyl (4-IPBP) and 4,4-DIPB decreased with the increase of those of 3-IPBP and 3,4-DIPB because of non-selective alkylation and isomerization at external acid sites that are alive in spite of severe deactivation. No significant isomerization of 4,4-DIPB over Ce/NaM25 was observed even at low propylene pressure. In the case of HM25, the isomerization of 4,4-DIPB to 3,4-DIPB occurred significantly under low propylene pressures, while it decreased under high pressure. These differences are ascribed to the differences of nature of acid sites between Ce/NaM25 and HM25 zeolites.  相似文献   

14.
Two plant-derived allelochemicals, berberine and -terthienyl (- T), were tested for their effects on the European corn borer,Ostrinia nubilalis, and its endoparasitoidDiadegma terebrans. The compounds were administered to the host insect in meridic diets, and the responses of the host larvae and parasitoids reared from treated hosts were measured in terms of growth parameters and survival. InO. nubilalis, survival to pupation and adult emergence were reduced significantly by the inclusion of berberine and -T in larval diets at a concentration of 100 g/g. However, in the parasitoid, adverse effects were much more apparent with the -T treatment than with the berberine treatment. -T and one of its metabolites were found in host larvae and in emerged adult parasitoids and their cocoons. Berberine residues were not detected. The implications of these responses to compounds of widely differing physiological properties are discussed with reference to host-plant resistance and biological control.  相似文献   

15.
Strontium ferrates and cobaltates with compositions SrFeO3- (0.060.40) and SrCoO3- (0.040.30) were synthesized. The dependence of the oxygen electrode properties on the value was examined in 1 mol dm–3 KOH solution. In the SrFeO3- series, the samples with 0.24<<0.29, showed the highest activity in both oxygen evolution and reduction reactions. In contrast, no strong dependence on the value was observed in SrCoO3-, which also showed a high catalytic activity for oxygen evolution.  相似文献   

16.
The conventional deduction procedure of computation of soil () and fertilizer () nutrient efficiencies for the amount of fertilizer required for specified yield targets does not make provision of the amount of soil nutrient derived by crops from the available pool of soil nutrients not accounted for in the amount extracted by a soil test procedure. The derivation of two mathematical models, viz., Tamil Nadu Agricultural University Model I [TNAU Model I] and Model II [TNAU Model II] is reported in this paper which aim at computing the soil () and fertilizer () nutrient efficiencies not accounted for by the conventional method.In the case of TNAU Model I, the relationship between the nutrient uptake (U) and the soil (S) and the fertilizer (F) nutrients was established by assuming a functional relationship of the type U =S +F such that 0 1 and 0 1. In TNAU Model II the same relationship was established as U =S +F + such that 0 1, 0 1 and > 0. The term in the latter model is a measure of the amount of soil nutrient the crop absorbs from a slowly available pool of nutrients not accounted for in the amounts extracted by the soil test procedure employed or applied through fertilizer.The field verification of these models is reported elsewhere.  相似文献   

17.
Summary Critical solution point and chain dimension were measured for branched polystyrene(BPS) in solution as a function of molecular weight(M) and compared with those for linear polystyrene(LPS). The critical concentration c of BPS was quite different from that of LPS at a fixed M, but the same at a fixed overlap-concentration *, i.e., plots of c vs. * fall on a single straight line for both BPS and LPS (gfc *). Reduced critical temperature c defined by gtc=(–Tc)/ [Tc: critical temperature, : the -temperature] was related to c as c c 2 for BPS, whereas c c for LPS.  相似文献   

18.
Summary Copolymers of halogenated styrenes and -methylene--butyrolactone were synthesized in bulk via free radical initiation. The polymerizations, in most cases, proceeded rapidly to high conversion. The high conversions obtained necessitated the use of high conversion methods to calculate reactivity ratios. In all the copolymerizations the -methylene--butyrolactone proved to be the more reactive monomer.  相似文献   

19.
The hydrogenation of CO2 was investigated over a rhodium catalyst supported on niobium oxide at atmospheric pressure. Niobium oxide was prepared by the hydrolysis of niobium chloride and its crystallitic structure was controlled by calcination temperature. It was found that the activity was lower but the selectivity of C2+ hydrocarbons was higher for the and forms than for the and forms of the niobium oxide.  相似文献   

20.
Soldiers of free-ranging termites of the genusLacessititermes (Isoptera, Nasutitermitinae) secrete from their frontal glands a mixture of monoterpenes, sesquiterpenes, and diterpenes.Lacessititermes ransoneti, L. laborator, andL. species A produce species-specific secretions, the composition being most complex forL. laborator. Apart from known mono- and dihydroxytrinervitadienes, the following new diterpenes were isolated and tentatively assigned as trinervita-1(15),8(19)-dien-2,3,9,14-tetraol 2,3,14-O-triacetate, trinervita-1(15),8(19)-dien-2,3,9,14-tetraol 2,3,14-O-triacetate, 2,3,9, 14-tetraacetoxy-1 (15), 8(19)-trinervitadiene, and 2,3,11,13-tetraacetoxy-1(15),8(19)-trinervitadiene. Data on intragenus chemical variations were subjected to canonical discriminant analysis and genetic distances among the species were calculated to depict intragenus identities and affinities.  相似文献   

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