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1.
Vapor phase hydroformylation of ethylene was studied with silica-supported metal catalysts. A cobalt metal catalyst derived from Co2(CO)8 gave propanal and its derivatives in as high selectivity of about 36% as Rh/SiO2 catalyst under the reaction conditions of 1.1 MPa of a gas-mixture of ArCOC2H4H2 = 1333 at 423–503 K. On the other hand, conventional cobalt catalysts derived from cobalt nitrate, chloride, or acetate, and other noble metal catalysts (Pd/SiO2 and Ir/SiO2) produced mainly ethane.  相似文献   

2.
When electroantennographic responses of maleYponomeuta malinellus Zeller to model compounds were determined at dosages of 0.3–30 ng, the strongest responses were obtained from (Z)-9-dodecen-1-ol acetate (Z9–12Ac). Also, strong responses were obtained from (Z)-11-tetradecenal (Z11–14A1) and (Z)-11-tetradecen-1-ol (Zl1–14OH). At a dosage of 0.3 ng,Z11–14A1 produced a stronger response thanZ11–14OH, while at a dosage of 30 ng,Z11–14OH andZ11–14A1 produced equal responses. Gas chromatographic and mass spectral analysis of extracts of female sex pheromone glands showed the presence ofZ9–12Ac, tetradecan-1-ol (14OH), (E)-11-tetradecen-1-ol (E11–14OH),Z11–14OH, hexadecan-1-ol, and hexadecan-1-ol acetate in a ratio of 0.62003710014035. In field tests,Z9–12Ac andZ11–14OH together were required for trap catch, and addition ofZ11–14A1,E11–14OH, 14OH, or (Z)-11-tetradecen-1-ol acetate did not increase catch. Ratios in rubber septa of 0.599.5 to 1.598.5 (Z9–12 Ac/Z11–14OH) captured the most males and captures were statistically equivalent for dosages of 10–1000 g/rubber septum. Traps baited with the synthetic lure produced better catches than those baited with females.Lepidoptera: Yponomeutidae.  相似文献   

3.
Six hydrocarbon components (2-methylhexadecane,n-heptadecane, 2-methylheptadecane, 2-methyloctadecane,n-nonadecane, and 2-methylnonadecane) were identified in sex-pheromone gland extracts and in airborne collections ofHolomelina lamae. Low variability in the ratio of components among individuals indicates tight regulation of blend composition. Minor changes were evident in the quantity and ratio of the blend as a function of time of day. Based on gland extracts, the total quantity of the six components increased from day 1 (X = 6299 ng) to day 4 (X = 7498 ng) and subsequently decreased. No significant correlations were found between total gland contents and wet or dry weights of moths. Emission rates ofH. lamae females were determined from pheromone adsorbed onto Porapak Q. Quantities released peaked shortly after the onset of calling and decreased rapidly as calling continued. Peak release rates ranged from 13 to 350 ng/10 min, and from 37 to 835 ng/60 min. Noncalling females did not emit detectable quantities of pheromone. Based on release rates and the rate of pulsation of the abdominal tip, the average amount released per pulse is not constant. The mean ratio of components released (0.787.45 84.802.842.591.53) was not very different from the ratio of components in gland extracts of 2-day-old females (0.704.1990.12 1.651.911.42). We propose that the blend is atomized rather than volatilized from the gland, thus retaining nearly the same ratios in the female's effluvium as in her gland.  相似文献   

4.
Sex gland extracts and washes ofEupoecilia ambiguella contain 10–20 ng/female of the primary sex pheromone componentZ-9-dodecenyl acetate (Z9–12Ac), accompanied by a number of related compounds. These areE-9-dodecenyl acetate (E9–12Ac),Z-9-dodecen-1-ol (Z9–12OH), saturated acetates of 12, 16, 18, and 20 carbons, and traces of a doubly unsaturated acetate, tentatively identified as a 9,11-dodecadienyl acetate. Octadecyl acetate predominates among the pheromone-related components, making up 1–2, occasionally 20–30 times the amount ofZ9–12Ac. The same compounds were also found in field-collected females and in effluvia.Z-9-Undecenyl acetate, which is a male attractant on its own, was also found in a sample of female effluvia. A hierarchy is observed in the ethological function of the pheromone components.Z9–12Ac is an attractant forE. ambiguella males. Dodecyl acetate (12Ac) is not attractive on its own but augments male catch when added to the main attractant. Addition of 18Ac augments attraction only when bothZ9–12Ac and 12Ac are present. Windtunnel tests demonstrate that 18Ac also raises the disorientation threshold, as previously shown for 12Ac. Other compounds, with the possible exception of additional saturated acetates, had either no effect on trap catch or, in the case ofE9–12Ac,Z9–12OH, andE-9,11-dodecadienyl acetate, were inhibitory above a certain level. A blend of roughly equal parts ofZ9–12Ac, 12Ac, and 18Ac provides the best attractant blend forE. ambiguella known to date.  相似文献   

5.
Partial oxidation of methane to synthesis gas   总被引:3,自引:0,他引:3  
Partial oxidation of methane to synthesis gas has been carried out over a number of transition metal catalysts under a range of conditions. It is found that the metals Ni, Ru, Rh, Pd, Ir and Pt, either supported on alumina or present in mixed metal oxide precursors, will bring the system to equilibrium. The yield of CO and H2 improves with increasing temperature in the range 650–1050 K, and decreases with increasing pressure between 1 and 20 atm. An excellent yield (92%) is obtained with a 421 N2CH4O2 ratio at 1050 K and atmospheric pressure, with a space velocity of 4×104 hour–1.  相似文献   

6.
Attraction ofCacoecimorpha pronubana male moths to blends of four sex pheromone components was studied in the wind tunnel.Z11–14Ac alone did not elicit upwind flight, admixture of 10%Z11–14OH or more led to successful attraction of males to the source. Attractivity of these binary blends was further enhanced by addition ofE11–14Ac orZ9–14Ac; the optimum was a blend ofZ11–14Ac,Z11–14OH,E11–14Ac, andZ9–14Ac at the proportion of 1003033. In ternary and quaternary blends, the effect ofZ11–14OH andE11–14Ac was strongest at 30% and 3%, respectively. By contrast,Z9–14Ac increased behavioral responses over a wide range.  相似文献   

7.
Electroantennogram (EAG) responses of maleRhopobota naevana (Hübner), the blackheaded fireworm, to all of the monoene straightchain 12- and 14-carbon alcohols and acetates implicated (Z)-11-tetradecenl-1-ol (Z11–14OH) and its acetate (Z11–14Ac) as sex pheromone components.Z11–14Ac produced the strongest EAG response of all compounds tested. Gas chromatography-mass spectrometry (GC-MS) analysis of extract of female sex pheromone glands (SPG) confirmed the presence ofZ11–14OH (125 pg/female) andZ11–14Ac (600 pg/female) (all other monoenes had different retention times). In field tests, traps baited withZ11–14OH alone captured males, but traps baited withZ11–14Ac alone did not. Traps baited with a combination ofZ11–14OH andZ11–14Ac in various ratios did not produce better trap catches thanZ11–14OH alone. (Z)-9-Dodecen-1-ol acetate (Z9–12Ac), reported by others to be a field attractant, did not produce trap catch in our tests, but in combination withZ11–14 OH (982 in septa corresponding to 95:5 in vapor,Z11–14OH toZ9–12AC) produced a sevenfold increase in catch overZ11–14OH alone. IfZ9–12AC had been present in extract of SPG at 2–5% ofZ11–14OH, it would not have been detected in our GC-MS experiment. Rhopobota naevana (Hübner) Lepidoptera: Tortricidae: Olethreutinae.  相似文献   

8.
Carbon supported alloy electrocatalysts based on Pt, Cu and Fe (atomic ratios PtCuFe=211 and 611) are prepared at various alloying temperatures and are characterized by XRD and TEM techniques. Powder XRD analyses show that Pt6CuFe clusters form a face-centered cubic structure (AuCu3 type), while Pt2CuFe clusters form an ordered alloy with a facecentered tetragonal structure (AuCu type) at higher temperature than 700C. Transmission electron micrographs reveal that the size of metal clusters increases gradually and size distribution becomes broader, as alloying temperature increases from 500 to 1100C.  相似文献   

9.
Two sex pheromone components, 3(Z),6(Z),9(Z)-nonadecatriene (3Z,6Z,9Z-19 H), and 3(Z),6(Z),9(Z)-eicosatriene (3Z,6Z,9Z-20 H), have been positively identified, and a third component, 6(Z),9(Z)-nonadecadiene (6(Z),9(Z)-19 H) has been tentatively identified from abdominal tip extracts of female spring cankerworm moths,Paleacrita vernata Peck (Lepidoptera Geometridae). The pheromone components were identified by a combination of gas chromatography, electroantennography, mass spectrometry, chemical tests, comparison with standards, and field testing. Only 3Z,6Z,9Z-20 H exhibited significant attractant activity when tested alone, and it was potentiated by the other two components. The attractive blend was an 821 ratio of 3Z,6Z,9Z-20H/3Z,6Z,9Z-19H/6Z,9Z-19H. However, the two-component blend of 3Z,6Z,9Z-20 H and 6Z,9Z-19 H (81 ratio) was as attractive as the three-component blend in further field tests. A series of related compounds, the diene monoepoxides available from epoxidation of C19 and C20 3Z,6Z,9Z-trienes, some of which have been found in the pheromone blends of other moth species, were tested as behavioral antagonists. The attraction of male moths to synthetic lures was suppressed by the addition of 6Z,9Z-cis-3,4-epoxy-nonadecadiene to the lures. Additional experiments were performed to determine the effects of lure dosage, trap height, and trap design on the numbers of male moths captured.Issued as NRCC 30711.  相似文献   

10.
Four acetates,Z-5-decenyl acetate,Z-5-,Z-7-, andZ-9-dodecenyl acetates, in microgram ratios of 120021 or 120062 were excellent, specific sex pheromone blends for capturing male redbacked cutworm moths in cone traps. Blends in ratios of 120021 and 220021 at 1000 g/ rubber septum dispenser remained highly effective for 6 weeks under field conditions. The essential minor components,Z-5-decenyl,Z-7-, andZ-9-dodecenyl acetates, became inhibitory at concentrations of about 10% in the blends, and this may be an important general phenomenon in lepidopteran pheromones. Blends involving a parapheromone,Z-5-undecenyl acetate, withZ-5-,Z-7-, andZ-9-dodecenyl acetate, in microgram ratios of 820021 or 2020062 were also excellent specific attractants for this species. TheZ-8-dodecenyl acetate had no obvious effect on the attraction of the redbacked cutworm males.  相似文献   

11.
Males of the redbanded leafroller,Argyrotaenia velutinana (Walker) (Lepidoptera: Tortricidae), were studied for their behavioral responses in laboratory olfactometers and in the field to the 3 components of the female-produced sex pheromone:cis-11-tetradecenyl acetate (c11–14Ac),trans-11-tetradecenyl acetate (t11–14Ac), and dodecyl acetate (12Ac). Dodecyl acetate, when evaporated with c11–14Ac (8%trans) in the field, modified the behavior of feral males nearby the chemical source, causing an increase in the frequency of landing and close approach to the pheromone dispenser. Apparently, an inflight behavioral modification concerning landing or not landing occurs within 60 cm of the source and is mediated by 12Ac. In laboratory olfactometers, c11–14Ac (8%trans) demonstrated a lower threshold for male activation than pure c11- and t11–14Ac and blends of the two isomers. Additionally, over a wide range of dosages, males responded with optimum wing-fanning response to c11–14Ac (8%trans) compared to pure c11–14Ac, c11–14:Ac (30%trans), and pure t11–14Ac, suggesting that thecistrans ratio rather than absolute amounts of either isomer, is a crucial factor in eliciting male response. When presented with c11–14Ac (8%trans) (11), dodecyl acetate caused a significant prolongation of wing-fanning over c11–14Ac (8%trans) alone and resulted in a greater percentage of males moving upwind to the source. Since the increase in wing-fanning and orientation occurred at higher concentrations of the 3-component mixture, the effect of 12Ac in the laboratory may reflect the close-range role of 12Ac in the field.  相似文献   

12.
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   

13.
Formulations of Mexican rice borer (MRB) pheromone components were more effective in capturing males in fields of sugarcane when dispensed from rubber septa than when evaporated from four other substrates. Concentrations of 0.63–10.0 mg of total pheromone per lure were effective over a 112-day period when formulated in rubber septa in a ratio of 811.3 of (Z)-13-octadecenyl acetate, (Z)-11-hexadecenyl acetate, and (Z)-13-octadecenal, respectively. Component ratios of 411.3 and 811.3 were equally effective in capturing male MRB, but efficacy decreased with higher relative concentrations of (Z)-13-octadecenyl acetate.Mention of a commercial or proprietary product does not constitute an endorsement by the USDA.  相似文献   

14.
The flight response of maleTrichoplusia ni was observed in a flight tunnel to a sex pheromone blend composed of six components:Z7–12Ac, 12Ac,Z5-12Ac, 11-12Ac,Z7-14Ac, and Z9-14Ac. The number of males reaching a 3000-g source of this blend was > 95%, equal to that observed to female glands and significantly greater than with the previously identified two-component blend (Z7-12Ac + 12Ac). In subtraction tests, all five-component blends, with the exception of the blend lacking the primary componentZ7-12Ac, and several four-component blends elicited similar peak levels of upwind flight, source contacts, and hairpencil displays to that observed with the six-component blend. We characterize the substitution of certain minor components for one another as a form of redundancy in the chemical signal and suggest that it contributes to response specificity and signal recognition in males. The results also support the concept that the full blend of components acts as a unit to influence male behavior at all phases of the response. Individual minor components were not responsible for eliciting specific behaviors in the sequence.  相似文献   

15.
For a series of catalysts containing 1 wt. % Pt and SnPt ratios ranging from ca. 1 to 8, the only crystalline alloy phase detected by XRD was SnPt (11). The XRD intensity of lines for the SnPt (11) alloy phase increase with increasing SnPt ratios, indicating the presence of unalloyed Pt in the samples containing low tin loadings.  相似文献   

16.
The sex pheromone components of the two sibling species of the dingy cutworm that occur on the prairies of western Canada were identified in abdomen-tip extracts from calling female moths. Three monounsaturated acetates, (Z)-7-dodecenyl acetate, (Z)-9-tetradecenyl acetate, and (Z)-11-hexadecenyl acetate, are common to both species in ratios of 100133 for species A and 0.30.5100 for species B. The most effective synthetic blends for the attraction of male moths in the field consisted of these three components in ratios of 1010 at 8.8g/lure for species A and 112000 at 500g/lure for species B. The addition of Z5-12Ac to either blend reduced the catches and the addition of Z7-12OH orZ11-16OH to the three-component blend reduced the catches of species B males. The species are morphologically indistinguishable, but the identity of the males attracted to the synthetic blends could be confirmed by their antennal responses to a test blend of the three components using a GC-EAD system. Both synthetic attractant blends are competitive with females and will be useful for studying the distribution, biology, and relative abundances of the two species.Contribution no. 3879005 of the Lethbridge Research Station.  相似文献   

17.
(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   

18.
Racemicezo-brevicomin, racemic frontalin, and myrcene were released at two proportions (51400 and 111), each at three levels (1 ×, 10 ×, and 100 ×) in a ponderosa pine forest in central California. The 51400 mix was based on an estimate of the relative amounts released from a ponderosa pine under attack by the western pine beetle,Dendroctonus brevicomis. MoreD. brevicomis were trapped at a source of the three compounds released at 51400 than were trapped at a source released at 111, at all three levels, but this difference was statistically significant only at the 1 × and 10 × levels. Sex ratio of trapped beetles and distribution of catch at the source of attractant and 5 m away apparently did not differ between relative release rates.Coleoptera: Scolytidae.Trade names are mentioned solely for information. No endorsement by the U.S. Department of Agriculture is implied.  相似文献   

19.
The effect of the structure of AlF3 supports in CrF3/AlF3 catalysts and their activity were studied, and a selection of suitable reaction conditions for fluorination of trichloroethylene and HCFC-133a was made. We found that neither AlF3 (- and -modifications) nor CrF3/-AlF3 exhibits significant activity for the reaction of HF with CCl2=CHC1 or CF3CH2Cl. However, CrF3/-AlF3 exhibits high activity, which increases with increasing surface area and decreasing crystallite size of the -AlF3 support, and that dramatically affects the fiuorination of CF3CH2Cl. Investigation of a series of CrF3/-AlF3 catalysts shows that the turnover rates per unit of the total surface area and of the free CrF3 surface area significantly increase with increasing content of Cr3+ loading. Optimum temperature for the reaction of HF with CCl2=CHCl is 260°C, while with CF3CH2Cl it is 350°C, with flow ratios HFTCE = 61 andHFHCFC-133a = 101.  相似文献   

20.
(Z)-11-Hexadecen-1-ol acetate (Z11–16Ac) free of theE isomer (<1%), hexadecan-1-ol acetate (16 Ac), and a hexadecen-1-ol [the (Z)-11 isomer based on the retention time on a Carbowax capillary column] were identified in extracts of the sex pheromone glands of adult virgin female armyworms,Pseudaletia unipuncta. Also, gas Chromatographic retention times on polar and nonpolar columns indicated the possible presence of (Z)-9-hexadecen-1-ol acetate (Z9–16Ac). The ratioZ11–16Ac/16Ac/Z11–16OH/Z9–16Ac was 10.150.130.02. Infield testsZ11–16 Ac was attractive alone, and the addition ofZ9–16Ac,Zll–16 OH, or 16 Ac singly or in combination in ratios found in the gland did not increase trap capture.Mention of a proprietary product does not constitute an endorsement of this product by the USDA.  相似文献   

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