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1.
Flowers of Ipomoea tricolor Cav. (cv. Heavenly Blue) were cut at various stages of development and evaluated for their ability to metabolize ethylene. Freshly cut buds or flowers were treated in glass containers for 8 hours with 6 μl/liter of highly purified 14C 2H 4. Following removal of dissolved 14C 2H 4, radioactivity was determined for the different flower tissues and trappd CO 2. 14C 2H 4 oxidation to 14CO 2 and tissue incorporation occurred at very low to nondetectable levels 2 to 3 days prior to flower opening. About 1 day prior to full bloom, just at the time when mature buds become responsive to ethylene (Kende and Hanson, Plant Physiol 1976, 57: 523-527), there was a dramatic increase in the capacity of the buds to oxidize 14C 2H 4 to 14CO 2. This activity continued to increase until the flower was fully opened reaching a peak activity of 2,500 dpm per three flowers per 8 hours. It then declined as the flower closed and rapidly senesced. A similar but smaller peak occurred in tissue incorporation and it was followed by a second peak during late flower senescence. This first peak in tissue incorporation and the dramatic peak in ethylene oxidation slightly preceded a large peak of natural ethylene production which accompanied flower senescence. The ethylene metabolism observed was clearly dependent on cellular metabolism and did not involve microorganisms since heat killing destroyed this activity and badly contaminated heat-killed flowers were unable to metabolize ethylene. 相似文献
2.
The relationship between ethylene action and metabolism was investigated in the etiolated pea seedling ( Pisum sativum L. cv. Alaska) by inhibiting ethylene action with Ag +, high CO 2, and low O 2 and then determining if ethylene metabolism was inhibited in a similar manner. Ag + (100 milligrams per liter) was clearly the most potent antiethylene treatment. Ag + pretreatment inhibited the growth retarding action of 0.2 microliters per liter ethylene by 48% and it also inhibited the incorporation of 0.2 microliters per liter 14C 2H 4 into pea tips by the same amount. As the ethylene concentration was increased from 0.2 to 30 microliters per liter, the effectiveness of Ag + in reducing ethylene action and metabolism declined in a similar fashion. Although Ag + significantly inhibited the incorporation of 14C 2H 4 into tissue metabolites, the oxidation of 14C 2H 4 to 14CO 2 was unaffected in the same tissue. 相似文献
3.
Cut carnations ( Dianthus caryophyllus L. cv. `Improved White Sim') were exposed to ultra high purity 14C 2H 4 (20 μl/1) during flower opening and senescence to study its incorporation and metabolism. During treatment precautions were taken to exclude inhibitory volatiles from rubber serum stoppers which were identified as CS 2 and COS. As with the pea seedling (Nature 1975, 255:144-147), cut carnations incorporated 14C 2H 4 into ethanol-soluble tissue metabolites and oxidized the hormone to 14CO 2. Oxidation increased from 0.5 to 3 dpm · mg dry wt −1·6 hr −1 during the period of flower opening and early petal wilt. As severe petal wilt set in, and the ovary increased in size and dry weight, oxidation increased to a peak of nearly 29 dpm · mg dry wt −1·6 hr −1. Concomitant with this peak was a similar rise in the rate of 14C 2H 4 incorporation into the petals, peduncle, bracts, and sepals. Much higher rates of incorporation were found for the reproductive and receptacle tissues. Incorporation into these tissues steadily increased during flower opening reaching a peak of over 160 dpm · mg dry wt −1 · 6 hr −1 just before full bloom. This peak preceded a peak of endogenous ethylene production while the 14C 2H 4 oxidation peak followed it. 相似文献
4.
The in vivo oxidation of the C 4 and C 5 of 5-aminolevulinic acid (ALA) to CO 2 has been studied in etiolated barley ( Hordeum vulgare L. var. Larker) leaves in darkness. The rate of 14CO 2 evolution from leaves fed [4- 14C]ALA is strongly inhibited by aminooxyacetate, anaerobiosis, and malonate. The rate of 14CO 2 evolution from leaves fed [5- 14C]ALA is also inhibited by these treatments but to a lesser extent. These results suggest that (a) one step in ALA catabolism is a transamination reaction and (b) the C 4 is oxidized to CO 2 via the tricarboxylic acid cycle to a greater extent than is the C 5. 相似文献
5.
The influence of indoleacetic acid, 0.03% CO 2, and malate on protein metabolism of etiolated Avena sativa coleoptile sections has been investigated. All three were found to elevate both the rate of incorporation of labeled leucine into protein, and the level of soluble protein. The combination of indoleacetic acid and CO 2 stimulated these values in an additive or weakly synergistic manner, in contrast to the nonadditive influence of malate and CO 2. Evidence is presented that cyclo-heximide inhibited the stimulation of protein synthesis by CO 2, and that indoleacetic acid increased the incorporation of 14C-bicarbonate into protein. These data are discussed in the context of CO 2-stimulated growth of etiolated tissue, and proposals that CO 2-stimulated growth involves dark CO 2 fixation. 相似文献
6.
Isolated cotyledons of Phaseolus vulgaris L. cv. Canadian Wonder accumulated 14C 2H 4 (0.7–1 l l -1) from air to give partition coefficients of 1 to 4, which greatly exceeded the value obtained with steam killed cotyledons (0.05) and with water (0.11). After 14C 2H 4 treatment, 98% of the 14C in the tissue remained as 14C 2H 4. The labelled ethylene accumulated by cotyledons was released only slowly (1–10% h -1) either in an air stream or into toluene. Heating to 60°C for 2 h, but not freezing and thawing, caused the immediate release of 14C 2H 4 from the tissue. Propylene and vinyl chloride competitively inhibited the accumulation of 14C 2H 4.Cotyledons emanated endogenous ethylene at a very low rate but after heating (although not freezing and thawing) 13 nl of ethylene per g fresh mass were released within minutes. It was concluded that french bean cotyledons hold ethylene in a compartmented form in sufficient amount to account for at least 200 h of emanation.Abbreviation PPO
diphenyloxazole 相似文献
7.
In organic solvents, 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-hydroxypyrazole (DTP) converted chlorophyll a and b extracted from rice seedlings ( Oryza sativa L. `Kinmaze') into pheophytin a and b, respectively. On comparing the chlorophyll-converting activity of DTP to those of acetic, glycolic, 2,4-dichlorobenzoic, monochloroacetic, 2,6-dichlorobenzoic, pyruvic, and dichloroacetic acids, it was demonstrated that DTP induced H + into chlorophyll specifically. 5-Hydroxypyrazoles, which seem to be dissociable, converted chlorophyll into pheophytin in vitro. These compounds also induced chlorosis in sedge seedlings ( Cyperus serotinus Rottb.), when the seedlings were grown in media containing these compounds. However, 5-hydroxypyrazoles, which seem to be undissociable, and analogs having no hydroxy group caused neither the chlorophyll conversion in vitro nor chlorosis in the seedlings. Chlorosis in barnyardgrass seedlings ( Echinochloa crus-galli Beauv. var. oryzicola Ohwi) induced by DTP was reversed by cultivating the seedlings in media containing DTP plus NaOH, KOH, NH 4OH, Ca(OH) 2, sodium acetate, sodium pyruvate, sodium succinate, or sodium fumarate. Accumulation of the vinyl pheoporphyrin fraction in 4- day-old etiolated radish cotyledons ( Raphanus sativus L. `Minowase 2') was enhanced by incubating the cotyledons with δ-aminolevulinic acid in the dark. However, simultaneous treatment with δ-aminolevulinic acid and DTP reduced accumulation of the fraction and promoted formation of the uro, copro, and protoporphyrin fractions. These results suggest that DTP blocks the synthesis of protochlorophyllide in intact plants and induces consequent chlorosis, and the H + -donating activity of DTP might cause the reduction of protochlorophyllide biosynthesis. 相似文献
8.
The assimilation of CO 2 by etiolated Hordeum vulgare seedlings during an illumination period indicates a conversion of the organisms to autotrophy. After 1 hour illumination, increases in the photo-assimilation of CO2 are observed and the distribution of C14 in the soluble fraction of the plants is predominantly in intermediates of the Calvin cycle. 相似文献
9.
Propylene uptake by intact pea seedlings ( Pisum sativum L. cv. Alaska) was easily detected using standard gas chromatographic techniques suggesting rapid metabolism. Comparative studies with highly purified 14C 3H 6 and 14C 2H 4 under aseptic conditions verified that propylene was rapidly metabolized and indicated that some aspects of its metabolism were similar to that of ethylene since 14C 3H 6, like 14C 2H 4 (Beyer, Nature 1975, 255: 144-147), was oxidized to 14CO 2 and incorporated into water-soluble tissue metabolites. However, 14C 2H 6 was metabolized at a substantially faster rate and unlike 14C 2H 4 the rate of 14C 3H 6 tissue incorporation exceeded its rate of oxidation to 14CO 2. In addition the neutral 14C-metabolites derived from 14C 3H 6 were chromatographically distinct from those formed from 14C 2H 4. 相似文献
10.
The initial products of photosynthesis by the C 3 species Flaveria cronquistii, the C 4 species F. trinervia, and the C 3-C 4 intermediate species F. ramosissima were determined using a pulse-chase technique with 14CO 2- 12CO 2. The intermediate species F. ramosissima incorporated at least 42% of the total soluble 14C fixed into malate and aspartate after 10 seconds of photosynthesis in 14CO 2, as compared with 90% for the C 4 species F. trinervia and 5% for the C 3 species F. cronquistii. In both F. ramosissima and F. trinervia, turnover of labeled malate and aspartate occurred during a chase period in 12CO 2, although the rate of turnover was slower in the intermediate species. Relative to F. cronquistii, F. ramosissima showed a reduced incorporation of radioactivity into serine and glycine during the pulse period. These results indicate that a functional C 4 pathway of photosynthesis is operating in F. ramosissima which can account for its reduced level of photorespiration, and that this species is a true biochemical intermediate between C 3 and C 4 plants. 相似文献
11.
Needles from phosphorus deficient seedlings of Pinus radiata D. Don grown for 8 weeks at either 330 or 660 microliters CO 2 per liter displayed chlorophyll a fluorescence induction kinetics characteristic of structural changes within the thylakoid chloroplast membrane, i.e. constant yield fluorescence (F O) was increased and induced fluorescence ([F P-F I]/F O) was reduced. The effect was greatest in the undroughted plants grown at 660 μl CO 2 L −1. By week 22 at 330 μl CO 2 L −1 acclimation to P deficiency had occurred as shown by the similarity in the fluorescence characteristics and maximum rates of photosynthesis of the needles from the two P treatments. However, acclimation did not occur in the plants grown at 660 μl CO 2 L −1. The light saturated rate of photosynthesis of needles with adequate P was higher at 660 μl CO 2 L −1 than at 330 μl CO 2 L −1, whereas photosynthesis of P deficient plants showed no increase when grown at the higher CO 2 concentration. The average growth increase due to CO 2 enrichment was 14% in P deficient plants and 32% when P was adequate. In drought stressed plants grown at 330 μl CO 2 L −1, there was a reduction in the maximal rate of quenching of fluorescence (R Q) after the major peak. Constant yield fluorescence was unaffected but induced fluorescence was lower. These results indicate that electron flow subsequent to photosystem II was affected by drought stress. At 660 μl CO 2 L −1 this response was eliminated showing that CO 2 enrichment improved the ability of the seedlings to acclimate to drought stress. The average growth increase with CO 2 enrichment was 37% in drought stressed plants and 19% in unstressed plants. 相似文献
12.
The incorporation of radioactive amino acids and of δ-amino[2,3- 3H 2]laevulinate into rat liver cytochromes b5 and c and cytochrome oxidase has been examined with and without protein-synthesis inhibitors. Cycloheximide promptly inhibits labelling of both haem and protein for cytochrome c in parallel fashion. Although incorporation of 14C-labelled amino acid into microsomal cytochrome b5 is also rapidly inhibited, cycloheximide incompletely inhibits haem labelling of cytochrome b5 and cytochrome a+a3, and inhibition occurs only after repeated antibiotic injections. The possibility of apo-protein pools, or of haem exchange, with a rapidly renewed `free' haem pool, is considered. Consistent with this model is the observation of non-enzymic haem exchange in vitro between cytochrome b5 and methaemoglobin. Chloramphenicol, injected intravenously over 5h, results in a 20–40% decrease in incorporation of δ-amino[2,3- 3H 2]laevulinate into haem a+a3 and haem of cytochromes b5 and c. With the dosage schedule of chloramphenicol studied, amino acid labelling of total liver protein and of cytochrome c was not inhibited. Similarly, ferrochelatase activity was not decreased. 相似文献
13.
Treatment of the ligands 3,5- tBu 2-2-(OH)C 6H 2CHNR [R = 2-(CO 2H)C 6H 4 ( 1a) and 2-(CO 2H)C 10H 6 ( 1b)] with trimethylborate, B(OMe) 3, in toluene yields, after work-up, the yellow crystalline complexes {[3,5- tBu 2-2-(O)C 6H 2CHNR]B(OMe)} [R = 2-(CO 2)C 6H 4 ( 2a) and 2-(CO 2)C 10H 6 ( 2b)], respectively. Further treatment of these complexes with trifluoromethanesulfonic (triflic) acid, CF 3SO 3H, followed by recrystallisation from tetrahydrofuran (thf) afforded the triflate salts [{3,5- tBu 2-2-(O)C 6H 2CHNR}B(thf)][CF 3SO 3] [R = 2-(CO 2)C 6H 4 ( 3a) and 2-(CO 2)C 10H 6 ( 3b)]. An electroluminescent device was constructed using 2a, which produced orange-green light with broad emission spectra (maximum brightness of 5 cd/m 2 being observed at 13 V). Compounds 1a and 2b·2MeCN have been characterised by single crystal X-ray structure determinations. 相似文献
14.
Changes in 14C 2H 4 metabolism in the abscission zone were monitored during cotton (cv. Deltapine 16) leaf abscission. Rates of 14C 2H 4 oxidation to 14CO 2 and tissue incorporation in abscission zone segments cut from the second true leaf of nonabscising leaves of intact plants were similar (about 200 disintegrations per minute per 0.1 gram dry weight per 5.5 hours) and relatively constant over a 5-day period. Deblading to induce abscission caused a dramatic rise in 14C 2H 4 oxidation, but tissue incorporation was not markedly affected. This rise occurred well before abscission, reaching a peak of 1,375 disintegrations per minute per 0.1 gram dry weight per 5.5 hours 2 days after deblading when abscission was 40%. The rate then gradually declined, but on day 5 when abscission reached completion, it was still nearly three times higher than in segments from nonabscising leaves. Application of 0.1 millimolar abscisic acid in lanolin to the debladed petiole ends increased the per cent abscission slightly and initially stimulated 14C 2H 4 oxidation. In contrast, naphthaleneacetic acid applied in a similar manner delayed and markedly inhibited both abscission and 14C 2H 4 oxidation. 相似文献
15.
When leaf discs of Xanthium strumarium L. and Salvia splendens L. are incubated in sealed flasks in the light, more C 2H 4 gas is released in the presence of added CO 2 (30-200 millimolar NaHCO 3) than without CO 2. In Salvia, the maximum rate of C 2H 4 release occurs when sufficient CO 2 (above 125 millimolar NaHCO 3) is added to saturate photosynthesis confirming previous studies. The maximum rate of C 2H 4 release from illuminated discs is similar to the rate in the dark with or without CO 2 in both species. Glycolate enhances a CO 2-dependent C 2H 4 evolution from illuminated leaf discs. However, the maximum rate of C 2H 4 release with glycolate is the same as that observed with saturating CO 2. When photosynthesis is inhibited by darkness or by 3-(3,4-dichlorophenyl)-1,1-dimethylurea, glycolate has no effect. Studies with [2,3-14C]-1-aminocyclopropane-1-carboxylic acid (ACC) show that the pattern of C2H4 release and the specific activity of the 14C2H4 in the presence and absence of glycolate is similar to that described above, indicating that glycolate does not alter uptake of the exogenously supplied precursor (ACC) or stimulate C2H4 release from an endogenous source at appreciable rates. Glycolate oxidase in vitro generates H2O2 which stimulates a slow breakdown of ACC to C2H4, but since exogenous glycolate is oxidized to CO2 in both the light and the dark it is argued that the glycolate-dependent increase in C2H4 release from illuminated leaf discs is not mediated directly by the action of enzymes of glycolate catabolism. The effects of glycolate and CO2 are not easily explained by changes in stomatal resistance. The data support the view that glycolate decarboxylation at subsaturating levels of CO2 in the light stimulates C2H4 release by raising the CO2 level in the tissue. 相似文献
16.
The anaerobic photodissimilation of acetate by Chlamydomonas reinhardii F-60 adapted to a hydrogen metabolism was studied utilizing manometric and isotopic techniques. The rate of photoanaerobic (N 2) acetate uptake was approximately 20 μmoles per milligram chlorophyll per hour or one-half that of the photoaerobic (air) rate. Under N 2, cells produced 1.7 moles H 2 and 0.8 mole CO 2 per mole of acetate consumed. Gas production and acetate uptake were inhibited by monofluoroacetic acid (MFA), 3-(3′,4′-dichlorophenyl)-1,1-dimethylurea (DCMU) and by H 2. Acetate uptake was inhibited about 50% by 5% H 2 (95% N 2). H 2 in the presence of MFA or DCMU stimulated acetate uptake and the result was interpreted to indicate a transition from oxidative to reductive metabolism. Carbon-14 from both [1- 14C]- and [2- 14C]acetate was incorporated under N 2 or H 2 into CO 2, lipids, and carbohydrates. The methyl carbon of acetate accumulated principally (75-80%) in the lipid and carbohydrate fractions, whereas the carboxyl carbon contributed isotope primarily to CO 2 (56%) in N 2. The presence of H 2 caused a decrease in carbon lost from the cell as CO 2 and a greater proportion of the acetate was incorporated into lipid. The results support the occurrence of anaerobic and light-dependent citric acid and glyoxylate cycles which affect the conversion of acetate to CO 2 and H 2 prior to its conversion to cellular material. 相似文献
17.
The activities of key C 4 enzymes in gel-filtered, whole-leaf extracts and the photosynthetic characteristics for reciprocal F 1 hybrids of Flaveria pringlei (C 3) and F. brownii (C 4-like species) were measured to determine whether any inherited C 4-photosynthetic traits are responsible for their reduced CO 2 compensation concentration values (AS Holaday, S Talkmitt, ME Doohan Plant Sci 41: 31-39). The activities of phosphoenolpyruvate carboxylase, pyruvate, orthophosphate dikinase, and NADP-malic enzyme (ME) for the reciprocal hybrids are only about 7 to 17% of those for F. brownii, but are three- to fivefold greater than the activities for F. pringlei. The low activities of these enzymes in the hybrids appear to be the result of a partial dominance of F. pringlei genes over certain F. brownii genes. However, no such dominance occurs with respect to the expression of genes for NADP-malate dehydrogenase, which is as active in the hybrids as in F. brownii. In contrast to the situation with the enzymes above, cytoplasmic factors appear to determine the inheritance of NAD-ME. The NAD-ME activity in each hybrid is comparable to that in the respective maternal parent. Pulse-chase 14CO 2 incorporation analyses at ambient CO 2 levels indicate that the hybrids initially assimilate 7 to 9% of the total assimilated CO 2 into C 4 acids as compared to 3.5% for F. pringlei. In the hybrids, the percentage of 14C in malate decreases from an average of 6.5 to 2.1% after a 60-second chase in 12CO 2/air. However, this apparent C 4-cycle activity is too limited or inefficient to substantially alter CO 2 exchange from that in F. pringlei, since the values of net photosynthesis and O 2 inhibition of photosynthesis are similar for the hybrids and F. pringlei. Also, the ratio of the internal to the external CO 2 concentration and the initial slopes of the plot of CO 2 concentration versus net photosynthesis are essentially the same for the hybrids and F. pringlei. At 45 micromoles CO 2 per mole and 0.21 mole O 2 per mole, the hybrids assimilate nearly fivefold more CO 2 into C 4 acids than does F. pringlei. Some turnover of the malate pool occurs in the hybrids, but the labelling of the photorespiratory metabolites, glycine and serine, is the same in these plants as it is in F. pringlei. Thus, although limited C 4-acid metabolism may operate in the hybrids, we conclude that it is not effective in altering O 2 inhibition of CO 2 assimilation. The ability of the hybrids to assimilate more CO 2 via phosphoenolpyruvate carboxylase at low levels of CO 2 than does F. pringlei may result in an increased rate of reassimilation of photorespiratory CO 2 and CO 2 compensation concentrations below that of their C 3 parent. If the hybrids do possess a limited C 4 cycle, it must operate intracellularly. They are not likely to have inherited an intercellular compartmentation of C 4 enzymes, since F. brownii has incomplete compartmentation of key C 3 and C 4 enzymes. 相似文献
18.
The pattern of photosynthetic carbon metabolism was determined in tissue cultures of Portulaca oleracea. Four-carbon acids are the most heavily labeled photosynthetic products during short term exposure to 14CO 2, containing greater than 40% of the total radioactivity incorporated. Phosphoglyceric acid and sugars account for only 10% of the label after equal exposure times. Other features of the CO 2 assimilation pattern in Portulaca callus tissue include a relatively large percentage of label located in various minor products throughout the time course studied, and a greater incorporation of 14C into sugars in tissue cultures than occurs in leaves. Ultrastructurally, the chloroplasts and cells of the callus are like those in the mesophyll cells of Portulaca leaves. The requirement for Kranz anatomy for operation of functional C 4 physiology is discussed. 相似文献
19.
Leaves of Flaveria brownii exhibited slightly higher amounts of oxygen inhibition of photosynthesis than the C 4 species, Flaveria trinervia, but considerably less than the C 3 species, Flaveria cronquistii. The photosynthetic responses to intercellular CO 2, light and leaf temperature were much more C 4-like than C 3-like, although 21% oxygen inhibited the photosynthetic rate, depending on conditions, up to 17% of the photosynthesis rate observed in 2% O 2. The quantum yield for CO 2 uptake in F. brownii was slightly higher than that for the C 4 species F. trinervia in 2% O 2, but not significantly different in 21% O 2. The quantum yield was inhibited 10% in the presence of 21% O 2 in F. brownii, yet no significant inhibition was observed in F. trinervia. An inhibition of 27% was observed for the quantum yield of F. cronquistii in the presence of 21% O 2. The photosynthetic response to very low intercellular CO 2 partial pressures exhibited a unique pattern in F. brownii, with a break in the linear slope observed at intercellular CO 2 partial pressure values between 15 and 20 μbar when analyzed in 21% O 2. No significant break was observed when analyzed in 2% O 2. When taken collectively, the gas-exchange results reported here are consistent with previous biochemical studies that report incomplete intercellular compartmentation of the C 3 and C 4 enzymes in this species, and suggest that F. brownii is an advanced, C 4-like C 3-C 4 intermediate. 相似文献
20.
The silver(I) salts [AgOR] ( 3a, R = C 9H 6N; 3b, R = C 6H 4-2-CHO, 3c, R = C 6H 4-2-Cl; 3d, R = C 6H 4-2-CN; 3e, R = C 6H 4-2-NO 2) are accessible by the stoichiometric reaction of [AgNO 3] ( 1) with HOR ( 2a, R = C 9H 6N; 2b, R = C 6H 4-2-CHO; 2c, R = C 6H 4-2-Cl; 2d, R = C 6H 4-2-CN; 2e, R = C 6H 4-2-NO 2) in presence of NEt 3. Treatment of 3a- 3e with P nBu 3 ( 4), P(OMe) 3 ( 5a) or P(OCH 2CF 3) 3 ( 5b) in the ratios of 1:1 and 1:2, respectively, produced complexes [L mAgOR] (L = P nBu 3, m = 1: 6a, R = C 9H 6N; 6b, R = C 6H 4-2-CHO; 6c, R = C 6H 4-2-Cl; 6d, R = C 6H 4-2-CN; 6e, R = C 6H 4-2-NO 2. m = 2: 7a, R = C 9H 4; 7b, R = C 6H 4-2-CHO; 7c, R = C 6H 4-2-Cl; 7d, R = C 6H 4-2-CN; 7e, R = C 6H 4-2-NO 2. L = P(OMe) 3, m = 1: 8a, R = C 6H 4-2-CHO; 8b, R = C 6H 4-2-NO 2. m = 2: 9, R = C 6H 4-2-NO 2. L = P(OCH 2CF 3) 3, m = 1: 10, R = C 6H 4-2-NO 2). Based on TGA, temperature-programmed and in situ molecular beam mass spectrometry metal-organic 7e was applied as CVD precursor in the deposition of silver onto glass substrates. The resulting silver films were characterized by XRD. The SEM image of a film grown from 7e at 350 °C showed a homogeneous surface with grain sizes of 40 nm. The molecular structures of 8b and 10 in the solid state were determined. They are isostructural and are cubane-like structured. Low-temperature 31P{ 1H} NMR studies showed that the title complexes are dynamic in solution and exchange at room temperature their ligands. 相似文献
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