Due to its toxicity, dichlorvos—a common organophosphate pesticide—poses significant risks to human health. This study utilized male Wistar rats to explore the potential protective effects of L-arginine supplementat...Due to its toxicity, dichlorvos—a common organophosphate pesticide—poses significant risks to human health. This study utilized male Wistar rats to explore the potential protective effects of L-arginine supplementation against dichlorvos-induced toxicity, focusing on cardiotoxicity, haematotoxicity and oxidative stress. The rats were divided into four groups: Control, L-arginine (L), Dichlorvos (D), and L-arginine + Dichlorvos (L + D). Dichlorvos was administered to the D group, L-arginine (100 mg/kg) to the L group, and both L-arginine and dichlorvos to the L + D group. The study evaluated various parameters, including cardiovascular, oxidative stress markers, and haematological indices. Significant changes in haematological parameters such as haemoglobin (Hb), haematocrit (HCT), and red blood cell count (RBC) indicated haematotoxicity after dichlorvos administration. Additionally, elevated cardiac markers, including lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB), suggested cardiotoxic effects. Exposure to dichlorvos also resulted in decreased antioxidant enzyme levels and increased oxidative stress indicators like malondialdehyde (MDA). Remarkably, L-arginine supplementation mitigated the damage caused by dichlorvos. It normalized the altered haematological parameters, demonstrating its protective effect against haematotoxicity. The rise in cardiac markers was reduced with L-arginine supplementation, indicating protection against cardiotoxicity. Moreover, L-arginine significantly decreased oxidative stress, as evidenced by lower MDA levels and restored antioxidant enzyme activity. In conclusion, L-arginine supplementation in male Wistar rats showed promising protective effects against dichlorvos-induced cardiotoxicity, haematotoxicity and oxidative stress. This suggests that L-arginine may offer a beneficial intervention to mitigate the adverse effects of dichlorvos on blood and heart health, paving the way for potential treatments for pesticide poisoning.展开更多
Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-ph...Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-phospine,promoted the formation of active species and enhanced the activity of hydroformylation over other tethered-phosphine modified Rh/SiO2 catalysts.展开更多
Matrix-bound phosphine (MBP) is a general term used to indicate non-gaseous reduced phosphorus compounds that are transformed into phosphine gas upon reaction with bases or acids. Antarctic seabird guanos and ornith...Matrix-bound phosphine (MBP) is a general term used to indicate non-gaseous reduced phosphorus compounds that are transformed into phosphine gas upon reaction with bases or acids. Antarctic seabird guanos and ornithogenic soils were used as materials to compare the different digestion methods for transforming matrix-bound phosphine into phosphine gas. The results demonstrated that more phosphine gas in most of Antarctic environmental materials was formed of matrix-bound phosphine by caustic digestion than by acidic digestion. The comparative study on different digestion methods also revealed that the fraction of MBP converted to gaseous phosphine during the digestion depended on the temperature. The optimal digestion temperature was close to 70℃and the optimal digestion time was about 20 min. Acidic conditions were more favorable for the release of matrix-bound phosphine compared to the neutral conditions. A proper water dilution can increase the production and emission of phosphine from the Antarctic penguin guanos.展开更多
We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experi...We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experimentally and fitted by the Toth equation, and the isosteric heat of PH_3 adsorption was calculated by the Clausius-Clapeyron Equation. The exhausted MWAC was regenerated by water washing and air drying. Moreover, the properties of five different samples were characterized by N_2 adsorption isotherm, SEM/EDS, XPS, and FTIR. The results showed that the maximum PH_3 equilibrium adsorption capacity was 595.56 mg/g. The MWAC had an energetically heterogeneous surface due to values of isosteric heat of adsorption ranging from 43 to 90 kJ/mol. The regeneration method provided an effective way for both adsorption species recycling and exhausted carbon regeneration. The high removal efficiency and big equilibrium adsorption capacity for PH_3 adsorption on the MWAC were related to its large surface area and high oxidation activity in PH_3 adsorption-oxidation to H_3 PO_4 and P_2 O_5. Furthermore, a possible PH_3 adsorption mechanism was proposed.展开更多
New flame-retardant polyimide-silver nanocomposite containing phosphine oxide moiety in the main chain was synthesized by a convenient ultraviolet irradiation technique.A precursor such as AgNO_3 was used as the sourc...New flame-retardant polyimide-silver nanocomposite containing phosphine oxide moiety in the main chain was synthesized by a convenient ultraviolet irradiation technique.A precursor such as AgNO_3 was used as the source of the silver particles.Polyimide 6 as a source of polymer was synthesized by polycondensation reaction of bis(3-aminophenyl) phenyl phosphine oxide 4 with pyromellitic anhydride 5 in the presence of iso-quinoline as base and in m-cresol solution.The resulting composite film was characterized by FTIR spectroscopy,X-ray diffraction(XRD),transmission electron microscopy(TEM),thermogravimetry(TGA) and differential scanning calorimetry(DSC).The average size of the nanometer Ag particles is about 10 nm.The temperature of 5 and 10%weight loss and also the char yield at 600℃of polyimide-silver nanocomposite 6a were higher than the pure PI 6.展开更多
[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a...[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a tabernacled smoke box, and the mortality rates of L. serricome F. eggs in the smoke box under conditions of different aluminium phosphide usage amount and different fumigation time were studied. In addition, the times needed by tabernacle and smoke box cen- ter to reach the phosphine concentration peak were recorded. [Result] The optimum conditions for killing the eggs of L. serricorne were as follows: temperature of (27± 2) ℃, relatively humidity of (45±5)%, aluminium phosphide usage amount of 1.5 g/m3 and effective exposure time of 96 h. The killing effect of mixed fumigation of phos- phine and carbon dioxide was increased with the extension of fumigation time. The increased usage amount of aluminium phosphide showed no significant effect on killing effect. The tabernacle space and smoke box center all required relatively short time to reach the phosphine concentration peak. If the tabernacle had a good airtightness, the overall fumigation time could be shortened. [Conclusion] The fumi- gation method is reliable, and it can be used for the control of L. serricorne F. in tobacco storage.展开更多
The objective of this research was to isolate a dichlorvos (2,2-dichlorovinyl dimethyl phosphate)-degrading strain of Ochrobactrum sp., and determine its effectiveness in remediation of a dichlorvos-contaminated soil....The objective of this research was to isolate a dichlorvos (2,2-dichlorovinyl dimethyl phosphate)-degrading strain of Ochrobactrum sp., and determine its effectiveness in remediation of a dichlorvos-contaminated soil. A dichlorvos-degrading bacterium (strain DDV-1) was successfully isolated and identified as an Ochrobactrumsp. based on its 16S rDNA sequence analysis. Strain DDV-1 was able to utilize dichlorvos as a sole carbon source, and the optimal pH and temperature for its cell growth and degradation were 7.0 and 30 ℃, respectively. Also, the growth and degradation of strain DDV-1 showed the same response to dissolved oxygen. In addition, the soil degradation test indicated that in soil spiked with 100 mg L-1 or 500 mg L-1 dichlorvos and inoculated with 0.5% or 1.0% (v/v) strain DDV-1, complete degradation of dichlorvos could be achieved in 24 h. The present study showed that strain DDV-1 was a fast dichlorvos-degrading bacterium in soil. However, further research will be needed to clarify the degradation pathway and the properties of the key enzymes involved in its biodegradation.展开更多
[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level...[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase (CAT) and peroxidase (POD) were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde (MDA) was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.展开更多
In this paper,a series of optically active MeO-BIPHEP-type ligands,(S)-6,6′-dimethoxy-2,2’-bis(di-p-alkoxyphenylphosphine)- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects o...In this paper,a series of optically active MeO-BIPHEP-type ligands,(S)-6,6′-dimethoxy-2,2’-bis(di-p-alkoxyphenylphosphine)- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects of para-substituted were observed,the results showed that the ruthenium catalysts[diphosphine RuCl;diamine]containing both t-Bu and i-Pr substitutions have better activities and enantioselectivities than the non-substituted ruthenium catalysts in the asymmetric hydrogenation of acetophenone.展开更多
A novel thermoregulated phosphine ligand PhP(CHCHO)CH(n=22) was synthesized and used for the Rh-catalyzed hydroformylation of mixed Colefins in aqueous/organic biphasic system.Under the optimized conditions,pressure =...A novel thermoregulated phosphine ligand PhP(CHCHO)CH(n=22) was synthesized and used for the Rh-catalyzed hydroformylation of mixed Colefins in aqueous/organic biphasic system.Under the optimized conditions,pressure =5 MPa (H:CO=1:1),phosphine/Rh =13(molar ratio),reaction time =6 h and temperature =130℃,the conversion of Colefins and the yield of aldehyde are 99%and 94%,respectively.The catalyst retained in aqueous phase can be easily separated from the product-containing organic phase by simple phase separation and the catalytic activity remains almost constant after four consecutive cycles.展开更多
Genotoxicity of dichlorvos and butachlor on erythrocytes of Rana zhenhaiensis tadpoles was investigated by the alkaline single-cell gel electrophoresis assay or comet assay.Tadpoles were treated for 24h in the laborat...Genotoxicity of dichlorvos and butachlor on erythrocytes of Rana zhenhaiensis tadpoles was investigated by the alkaline single-cell gel electrophoresis assay or comet assay.Tadpoles were treated for 24h in the laboratory with different concentrations of the testing agents,2.256,4.512,6.768,9.024,11.280mg/L for dichlorvos and 0.292,0.584,0.876,1.168,1.460mg/L for butachlor,to use the comet Assay to test for the significance of dosage responsiveness to an increase in DNA damage,asmeasured by themean DNA tail length-to-width ratio.The concentrations of 4.512mg/L dichlorvos and 0.876mg/L butachlor resulted in highly significant increases in DNA damage of the tadpoles.There were linear correlations between themean DNA tail length-to-width ratio and the concentrations of the two test substances.Our results showed that the two commonly used agricultural chemicals caused dose dependent DNA damage of amphibians,and that comet assaymight be a useful tool formeasuring DNA damage of tadpoles exposed in the field.展开更多
Matrix-bound phosphine was determined in the Jiaozhou Bay coastal sediment, in prawn-pond bottom soil, in the eutrophic lake Wulongtan, in the sewage sludge and in paddy soil as well. Results showed that matrix-bound ...Matrix-bound phosphine was determined in the Jiaozhou Bay coastal sediment, in prawn-pond bottom soil, in the eutrophic lake Wulongtan, in the sewage sludge and in paddy soil as well. Results showed that matrix-bound phosphine levels in freshwater and coastal sediment, as well as in sewage sludge, are significantly higher than that in paddy soil. The correlation between matrix bound phosphine concentrations and organic phosphorus contents in sediment samples is discussed.展开更多
A highly efficient and regio-/stereoselective method of hydrosilylating terminal alkynes was developed using Pt(DVDS)-tri(t-butyl) phosphine catalyst system at room temperature.Trans-products or alpha-products were ob...A highly efficient and regio-/stereoselective method of hydrosilylating terminal alkynes was developed using Pt(DVDS)-tri(t-butyl) phosphine catalyst system at room temperature.Trans-products or alpha-products were obtained almost exclusively depending on the alkynes and silanes employed.展开更多
A fluorescent ternary europium complex containing bis (diphenyl phosphine oxide) methane which functioned as both a neutral and anion ligand, and thenoyltrifluoroacetonato anion was synthesized and characterized by e...A fluorescent ternary europium complex containing bis (diphenyl phosphine oxide) methane which functioned as both a neutral and anion ligand, and thenoyltrifluoroacetonato anion was synthesized and characterized by elemental analysis, DTA TG analysis, UV Vis, FT IR and MS spectroscopy. The chemical formula is proved to be Eu(TTA)(MPPO)(HMPPO)·(NO 3)·2H 2O. Its luminescence quantum efficiency(in acetonitrile, 26 3%) is approximately the same as that of the commonly used red emission luminescent compound, Eu(TTA) 3(TPPO) 2 (TPPO is triphenyl phosphine oxide). The new complex has comparatively long fluorescence lifetime.展开更多
The crystal structure of the title compound 3--MBPA, C26H27O5P (Mr.= 450. 44 ). has been determined by single--crystal X-ray diffraction. The crystal ismonoclinic with space group P21, a= 9. 294(l), b= 7. 999(1), c= 1...The crystal structure of the title compound 3--MBPA, C26H27O5P (Mr.= 450. 44 ). has been determined by single--crystal X-ray diffraction. The crystal ismonoclinic with space group P21, a= 9. 294(l), b= 7. 999(1), c= 15. 925(2) A,β=96. 17(5)°, V= 1176. 9 A 3, Dc=l. 271 g/cm3, F(000)=476, μ=12. 99 cm-1,Z=', Z=2, and final R = 0. 045 and Ru= 0. 057 for 1882 reflections (I≥3a(I) ). Structureanalysis revealed that the pyranose and 4, 6--O--benzylidene ring of the title compoundadopt a distorted chair conformation and the diphenylphosphino, OH and OMe groupsare in pseudo--axial position.展开更多
The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dp...The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dppm-Q, dppe-Q, dppp-Q and dppb-Q, the incorporated phosphino-fragments were responsible for Rh-catalyzed hydroformylation and the phosphoniums were in charge of the subsequent acetalization as the Lewis acid catalysts. Moreover, the diphosphonium-based ionic liquid of dppb-DQ could be applied as a co-solvent to immobilize the Rh/dppb-Q catalytic system with the advantages of the improved catalytic performance, the available catalyst recyclability, and the wide generality for the substrates.展开更多
Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteri...Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteriorate device efficiency,but also facilitate chemical degradation with ion migration,resulting in restricted device lifetime.Herein,we present a novel type of phosphines as the point defects stabilizer for hybrid perovskite solar cells with enhanced performances.Three phosphines with varied side groups of tributyl,trioctyl and triphenyl are exampled as the dopants in perovskite films.The group dependent redox properties were observed in the perovskite film,dependent on their molecular weights and steric hinderances of phosphines.The partially oxidized tributyl phosphine(TBUP)with additional tributyl phosphine oxides(TBPO)is efficient in reduction of lead(Pb)^(0) and iodine(I)^(0) concentrations during the device fabrication and operation.The device with TBUP-TBPO pair showed enhanced power conversion efficiency(PCE)to 20.48% and maintain 91.7% of their initial PCEs after 500 h at 65℃ thermal annealing.Thus,this work presents an efficient route of utilize the phosphine species to reduce point defects in the perovskite film,which promoting further development of novel phosphorous additives with defects stabilization,interface passivation and encapsulation for low-cost solution processed PSCs.展开更多
The Henry's Law constant (k) for phosphine in seawater was determined by multiple phase equilibration combined with headspace gas chromatography. The effects of pH, temperature, and salinity on k were studied. The ...The Henry's Law constant (k) for phosphine in seawater was determined by multiple phase equilibration combined with headspace gas chromatography. The effects of pH, temperature, and salinity on k were studied. The k value for phosphine in natural seawater was 6.415 at room temperature (approximately 23℃). This value increases with increases in temperature and salinity, but no obvious change was observed at different pH levels. At the same temperature, there was no significant difference between the k for phosphine in natural seawater and that in artificial seawater. This implies that temperature and salinity are major determining factors for k in marine environment. Double linear regression with Henry's Law constants for phosphine as a function of temperature and salinity confirmed our observations. These results provide a basis for the measurement of trace phosphine concentrations in seawater, and will be helpful for future research on the status of phosphine in the oceanic biogeochemical cycle of phosphorus.展开更多
The three-component coupling reaction of ethyl propiolate (1), phthalimide (2), and aldehyde (3) catalyzed by tripheny- lphosphine, was developed. A solution of an equivalent amount of 1 and 2 in benzaldehyde (3a) in ...The three-component coupling reaction of ethyl propiolate (1), phthalimide (2), and aldehyde (3) catalyzed by tripheny- lphosphine, was developed. A solution of an equivalent amount of 1 and 2 in benzaldehyde (3a) in the presence of 30 mol% of PPh3 was heated at 100?C for 48 h to give N-(1-ethoxycarbonyl-3-oxo-3-phenylpropyl)phthalimide (4a) in 83% yield. This reaction was thought to proceed via vinylphosphonium salt formed from the reaction of ethyl propiolate (1) with triphenylphosphine in situ.展开更多
文摘Due to its toxicity, dichlorvos—a common organophosphate pesticide—poses significant risks to human health. This study utilized male Wistar rats to explore the potential protective effects of L-arginine supplementation against dichlorvos-induced toxicity, focusing on cardiotoxicity, haematotoxicity and oxidative stress. The rats were divided into four groups: Control, L-arginine (L), Dichlorvos (D), and L-arginine + Dichlorvos (L + D). Dichlorvos was administered to the D group, L-arginine (100 mg/kg) to the L group, and both L-arginine and dichlorvos to the L + D group. The study evaluated various parameters, including cardiovascular, oxidative stress markers, and haematological indices. Significant changes in haematological parameters such as haemoglobin (Hb), haematocrit (HCT), and red blood cell count (RBC) indicated haematotoxicity after dichlorvos administration. Additionally, elevated cardiac markers, including lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB), suggested cardiotoxic effects. Exposure to dichlorvos also resulted in decreased antioxidant enzyme levels and increased oxidative stress indicators like malondialdehyde (MDA). Remarkably, L-arginine supplementation mitigated the damage caused by dichlorvos. It normalized the altered haematological parameters, demonstrating its protective effect against haematotoxicity. The rise in cardiac markers was reduced with L-arginine supplementation, indicating protection against cardiotoxicity. Moreover, L-arginine significantly decreased oxidative stress, as evidenced by lower MDA levels and restored antioxidant enzyme activity. In conclusion, L-arginine supplementation in male Wistar rats showed promising protective effects against dichlorvos-induced cardiotoxicity, haematotoxicity and oxidative stress. This suggests that L-arginine may offer a beneficial intervention to mitigate the adverse effects of dichlorvos on blood and heart health, paving the way for potential treatments for pesticide poisoning.
基金financially supported by the National Natural Science Foundation of China(21273227,20903090)~~
文摘Rh/SiO2 catalysts with tethered-phosphines with different alkyl spacer lengths have been prepared,tested and characterized.Lengthening the alkyl spacer of the tethered-phosphine improved the flexibility of tethered-phospine,promoted the formation of active species and enhanced the activity of hydroformylation over other tethered-phosphine modified Rh/SiO2 catalysts.
基金supported by the National Natural Sci-ence Foundation of China (No. 40676005)
文摘Matrix-bound phosphine (MBP) is a general term used to indicate non-gaseous reduced phosphorus compounds that are transformed into phosphine gas upon reaction with bases or acids. Antarctic seabird guanos and ornithogenic soils were used as materials to compare the different digestion methods for transforming matrix-bound phosphine into phosphine gas. The results demonstrated that more phosphine gas in most of Antarctic environmental materials was formed of matrix-bound phosphine by caustic digestion than by acidic digestion. The comparative study on different digestion methods also revealed that the fraction of MBP converted to gaseous phosphine during the digestion depended on the temperature. The optimal digestion temperature was close to 70℃and the optimal digestion time was about 20 min. Acidic conditions were more favorable for the release of matrix-bound phosphine compared to the neutral conditions. A proper water dilution can increase the production and emission of phosphine from the Antarctic penguin guanos.
基金Funded by the National Natural Science Foundation of China(51566017)
文摘We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experimentally and fitted by the Toth equation, and the isosteric heat of PH_3 adsorption was calculated by the Clausius-Clapeyron Equation. The exhausted MWAC was regenerated by water washing and air drying. Moreover, the properties of five different samples were characterized by N_2 adsorption isotherm, SEM/EDS, XPS, and FTIR. The results showed that the maximum PH_3 equilibrium adsorption capacity was 595.56 mg/g. The MWAC had an energetically heterogeneous surface due to values of isosteric heat of adsorption ranging from 43 to 90 kJ/mol. The regeneration method provided an effective way for both adsorption species recycling and exhausted carbon regeneration. The high removal efficiency and big equilibrium adsorption capacity for PH_3 adsorption on the MWAC were related to its large surface area and high oxidation activity in PH_3 adsorption-oxidation to H_3 PO_4 and P_2 O_5. Furthermore, a possible PH_3 adsorption mechanism was proposed.
文摘New flame-retardant polyimide-silver nanocomposite containing phosphine oxide moiety in the main chain was synthesized by a convenient ultraviolet irradiation technique.A precursor such as AgNO_3 was used as the source of the silver particles.Polyimide 6 as a source of polymer was synthesized by polycondensation reaction of bis(3-aminophenyl) phenyl phosphine oxide 4 with pyromellitic anhydride 5 in the presence of iso-quinoline as base and in m-cresol solution.The resulting composite film was characterized by FTIR spectroscopy,X-ray diffraction(XRD),transmission electron microscopy(TEM),thermogravimetry(TGA) and differential scanning calorimetry(DSC).The average size of the nanometer Ag particles is about 10 nm.The temperature of 5 and 10%weight loss and also the char yield at 600℃of polyimide-silver nanocomposite 6a were higher than the pure PI 6.
文摘[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a tabernacled smoke box, and the mortality rates of L. serricome F. eggs in the smoke box under conditions of different aluminium phosphide usage amount and different fumigation time were studied. In addition, the times needed by tabernacle and smoke box cen- ter to reach the phosphine concentration peak were recorded. [Result] The optimum conditions for killing the eggs of L. serricorne were as follows: temperature of (27± 2) ℃, relatively humidity of (45±5)%, aluminium phosphide usage amount of 1.5 g/m3 and effective exposure time of 96 h. The killing effect of mixed fumigation of phos- phine and carbon dioxide was increased with the extension of fumigation time. The increased usage amount of aluminium phosphide showed no significant effect on killing effect. The tabernacle space and smoke box center all required relatively short time to reach the phosphine concentration peak. If the tabernacle had a good airtightness, the overall fumigation time could be shortened. [Conclusion] The fumi- gation method is reliable, and it can be used for the control of L. serricorne F. in tobacco storage.
基金Project supported by the National High Technology Research and Development Program of China (863 Program)(Nos.2001AA214121, 2002AA246081 and 2003AA241150)the National Key Technologies Research and Development Program of China during the 9th Five-Year Plan Period (No. 2002BA516A01)the National Natural Science Foundation of China (No. 30400013).
文摘The objective of this research was to isolate a dichlorvos (2,2-dichlorovinyl dimethyl phosphate)-degrading strain of Ochrobactrum sp., and determine its effectiveness in remediation of a dichlorvos-contaminated soil. A dichlorvos-degrading bacterium (strain DDV-1) was successfully isolated and identified as an Ochrobactrumsp. based on its 16S rDNA sequence analysis. Strain DDV-1 was able to utilize dichlorvos as a sole carbon source, and the optimal pH and temperature for its cell growth and degradation were 7.0 and 30 ℃, respectively. Also, the growth and degradation of strain DDV-1 showed the same response to dissolved oxygen. In addition, the soil degradation test indicated that in soil spiked with 100 mg L-1 or 500 mg L-1 dichlorvos and inoculated with 0.5% or 1.0% (v/v) strain DDV-1, complete degradation of dichlorvos could be achieved in 24 h. The present study showed that strain DDV-1 was a fast dichlorvos-degrading bacterium in soil. However, further research will be needed to clarify the degradation pathway and the properties of the key enzymes involved in its biodegradation.
基金Supported by National Natural Science Foundation of China(41071305)~~
文摘[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase (CAT) and peroxidase (POD) were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde (MDA) was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.
基金the NSFC(No.20272037),the Doctor's Foundation of Education Ministry of China(No.20030610022)Foundation of Xihua University(No.R0723315) and(No.07ZA109) for the financial support of this work.
文摘In this paper,a series of optically active MeO-BIPHEP-type ligands,(S)-6,6′-dimethoxy-2,2’-bis(di-p-alkoxyphenylphosphine)- 1,1′-biphenyl were synthesized and used to prepare the ruthenium complex.The effects of para-substituted were observed,the results showed that the ruthenium catalysts[diphosphine RuCl;diamine]containing both t-Bu and i-Pr substitutions have better activities and enantioselectivities than the non-substituted ruthenium catalysts in the asymmetric hydrogenation of acetophenone.
基金the financial support from the Program for New Century Excellent Talents in University (No.NCET-07-0138)the Science and Technology Project in Universities from the Education Department of Liaoning Province(No.2008T233).
文摘A novel thermoregulated phosphine ligand PhP(CHCHO)CH(n=22) was synthesized and used for the Rh-catalyzed hydroformylation of mixed Colefins in aqueous/organic biphasic system.Under the optimized conditions,pressure =5 MPa (H:CO=1:1),phosphine/Rh =13(molar ratio),reaction time =6 h and temperature =130℃,the conversion of Colefins and the yield of aldehyde are 99%and 94%,respectively.The catalyst retained in aqueous phase can be easily separated from the product-containing organic phase by simple phase separation and the catalytic activity remains almost constant after four consecutive cycles.
基金granted by the Natural Science Foundation of Fujian,China(2009J01129)the Education Department Foundation of Fujian,China(2007F5033)
文摘Genotoxicity of dichlorvos and butachlor on erythrocytes of Rana zhenhaiensis tadpoles was investigated by the alkaline single-cell gel electrophoresis assay or comet assay.Tadpoles were treated for 24h in the laboratory with different concentrations of the testing agents,2.256,4.512,6.768,9.024,11.280mg/L for dichlorvos and 0.292,0.584,0.876,1.168,1.460mg/L for butachlor,to use the comet Assay to test for the significance of dosage responsiveness to an increase in DNA damage,asmeasured by themean DNA tail length-to-width ratio.The concentrations of 4.512mg/L dichlorvos and 0.876mg/L butachlor resulted in highly significant increases in DNA damage of the tadpoles.There were linear correlations between themean DNA tail length-to-width ratio and the concentrations of the two test substances.Our results showed that the two commonly used agricultural chemicals caused dose dependent DNA damage of amphibians,and that comet assaymight be a useful tool formeasuring DNA damage of tadpoles exposed in the field.
文摘Matrix-bound phosphine was determined in the Jiaozhou Bay coastal sediment, in prawn-pond bottom soil, in the eutrophic lake Wulongtan, in the sewage sludge and in paddy soil as well. Results showed that matrix-bound phosphine levels in freshwater and coastal sediment, as well as in sewage sludge, are significantly higher than that in paddy soil. The correlation between matrix bound phosphine concentrations and organic phosphorus contents in sediment samples is discussed.
文摘A highly efficient and regio-/stereoselective method of hydrosilylating terminal alkynes was developed using Pt(DVDS)-tri(t-butyl) phosphine catalyst system at room temperature.Trans-products or alpha-products were obtained almost exclusively depending on the alkynes and silanes employed.
文摘A fluorescent ternary europium complex containing bis (diphenyl phosphine oxide) methane which functioned as both a neutral and anion ligand, and thenoyltrifluoroacetonato anion was synthesized and characterized by elemental analysis, DTA TG analysis, UV Vis, FT IR and MS spectroscopy. The chemical formula is proved to be Eu(TTA)(MPPO)(HMPPO)·(NO 3)·2H 2O. Its luminescence quantum efficiency(in acetonitrile, 26 3%) is approximately the same as that of the commonly used red emission luminescent compound, Eu(TTA) 3(TPPO) 2 (TPPO is triphenyl phosphine oxide). The new complex has comparatively long fluorescence lifetime.
文摘The crystal structure of the title compound 3--MBPA, C26H27O5P (Mr.= 450. 44 ). has been determined by single--crystal X-ray diffraction. The crystal ismonoclinic with space group P21, a= 9. 294(l), b= 7. 999(1), c= 15. 925(2) A,β=96. 17(5)°, V= 1176. 9 A 3, Dc=l. 271 g/cm3, F(000)=476, μ=12. 99 cm-1,Z=', Z=2, and final R = 0. 045 and Ru= 0. 057 for 1882 reflections (I≥3a(I) ). Structureanalysis revealed that the pyranose and 4, 6--O--benzylidene ring of the title compoundadopt a distorted chair conformation and the diphenylphosphino, OH and OMe groupsare in pseudo--axial position.
基金financially supported by the National Natural Science Foundation of China(Nos.21673077,21473058,and 21273077)
文摘The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dppm-Q, dppe-Q, dppp-Q and dppb-Q, the incorporated phosphino-fragments were responsible for Rh-catalyzed hydroformylation and the phosphoniums were in charge of the subsequent acetalization as the Lewis acid catalysts. Moreover, the diphosphonium-based ionic liquid of dppb-DQ could be applied as a co-solvent to immobilize the Rh/dppb-Q catalytic system with the advantages of the improved catalytic performance, the available catalyst recyclability, and the wide generality for the substrates.
基金supported financially by the National Key Research and Development Plan,China(2017YFE0131900)the National Science Foundation of China(NSFC 51672202,21875178)+1 种基金the Technological Innovation Key Project of Hubei Province(2018AAA048)the support the“Chutian Scholar Program”of Hubei Province,China。
文摘Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteriorate device efficiency,but also facilitate chemical degradation with ion migration,resulting in restricted device lifetime.Herein,we present a novel type of phosphines as the point defects stabilizer for hybrid perovskite solar cells with enhanced performances.Three phosphines with varied side groups of tributyl,trioctyl and triphenyl are exampled as the dopants in perovskite films.The group dependent redox properties were observed in the perovskite film,dependent on their molecular weights and steric hinderances of phosphines.The partially oxidized tributyl phosphine(TBUP)with additional tributyl phosphine oxides(TBPO)is efficient in reduction of lead(Pb)^(0) and iodine(I)^(0) concentrations during the device fabrication and operation.The device with TBUP-TBPO pair showed enhanced power conversion efficiency(PCE)to 20.48% and maintain 91.7% of their initial PCEs after 500 h at 65℃ thermal annealing.Thus,this work presents an efficient route of utilize the phosphine species to reduce point defects in the perovskite film,which promoting further development of novel phosphorous additives with defects stabilization,interface passivation and encapsulation for low-cost solution processed PSCs.
基金Supported by the National Natural Science Foundation of China (Nos.30970522,40576058)the National Natural Science Foundation of China for Creative Research Groups (No.41121064)
文摘The Henry's Law constant (k) for phosphine in seawater was determined by multiple phase equilibration combined with headspace gas chromatography. The effects of pH, temperature, and salinity on k were studied. The k value for phosphine in natural seawater was 6.415 at room temperature (approximately 23℃). This value increases with increases in temperature and salinity, but no obvious change was observed at different pH levels. At the same temperature, there was no significant difference between the k for phosphine in natural seawater and that in artificial seawater. This implies that temperature and salinity are major determining factors for k in marine environment. Double linear regression with Henry's Law constants for phosphine as a function of temperature and salinity confirmed our observations. These results provide a basis for the measurement of trace phosphine concentrations in seawater, and will be helpful for future research on the status of phosphine in the oceanic biogeochemical cycle of phosphorus.
文摘The three-component coupling reaction of ethyl propiolate (1), phthalimide (2), and aldehyde (3) catalyzed by tripheny- lphosphine, was developed. A solution of an equivalent amount of 1 and 2 in benzaldehyde (3a) in the presence of 30 mol% of PPh3 was heated at 100?C for 48 h to give N-(1-ethoxycarbonyl-3-oxo-3-phenylpropyl)phthalimide (4a) in 83% yield. This reaction was thought to proceed via vinylphosphonium salt formed from the reaction of ethyl propiolate (1) with triphenylphosphine in situ.