Utilizing solvent extraction to separate alkanes and olefins from catalytic light gasoline is an effective method for maximizing the utility of gasoline fractions.This study presents the determination of liquid-liquid...Utilizing solvent extraction to separate alkanes and olefins from catalytic light gasoline is an effective method for maximizing the utility of gasoline fractions.This study presents the determination of liquid-liquid equilibrium data for the ternary system of 1-hexene-n-hexane-3-methylsulfolane at 30℃,40℃,and 50℃under atmospheric pressure.The obtained data facilitated the construction of a ternary phase diagram for the system.The results showed that the extraction selectivity of 1-hexene/n-hexane exceeded 1.5 when using 3-methylsulfolane as the extraction solvent.Furthermore,the thermodynamic consistency of the experimental data was examined using Hand’s equation and the Othmer-Tobias method.The correlation coefficient,R^(2)≥0.9578,indicated the acceptable reliability of the phase equilibrium data.Subsequently,the NRTL(non-random two liquid)model was used to correlate the liquid-liquid phase equilibrium data and derive the binary interaction parameter.Notably,the results demonstrated that the root mean square deviation of the NRTL model correlation values from the experimental values did not exceed 2.5%.展开更多
It is demonstrated that (3Z)-nonenal (NON) and (3Z)-hexenal (HEX) are oxidized in a cascade by lipoxygenase (LOX) and hydroperoxide peroxygenase (HP peroxygenase) into (2E)-4-hydroxy-2- nonenal (HNE) and (2E)-4-hydrox...It is demonstrated that (3Z)-nonenal (NON) and (3Z)-hexenal (HEX) are oxidized in a cascade by lipoxygenase (LOX) and hydroperoxide peroxygenase (HP peroxygenase) into (2E)-4-hydroxy-2- nonenal (HNE) and (2E)-4-hydroxy-2-hexenal (HHE), respectively. In turn, HNE inactivates LOX terminating the cascade. The hydroxy-alkenals produced serve to inhibit plant pathogens, which initiated the cascade. In addition to LOX, other unknown oxygenases may be involved in the cascade.展开更多
Several methods including molecular mechanics, molecular dynamics, ONIOM that combines quantum chemistry with molecular mechanics and standard quantum chemistry are used to study the configuration and electron structu...Several methods including molecular mechanics, molecular dynamics, ONIOM that combines quantum chemistry with molecular mechanics and standard quantum chemistry are used to study the configuration and electron structures of an adduct of the DNA segment d(ATACATG*G*TACATA)·d(TATGTACCATGTAT) with cis-[Pt(NH3)(2-Picoline)]2+. The investigation shows that the configuration optimized by ONIOM is similar to that determined by NMR. Strong chemical bonds between Pt of the complex and two N7s of neighboring guanines in the DNA duplex and hydrogen bond between the NH3 of the complex and O6 of a nearby guanine have a large impact on the configuration of the adduct. Chemical bonds, the aforementioned hydrogen bond, and the interaction between a methyl of the complex and a methyl of the base in close proximity are critical for the complex to specifically recognize DNA.展开更多
Plagiodera versicolora Laicharting is a highly damaging leaf beetle foraging on willow leaves.In willow germplasm collections,observation has shown that Salix suchowensis Cheng was severely foraged by this leaf beetle...Plagiodera versicolora Laicharting is a highly damaging leaf beetle foraging on willow leaves.In willow germplasm collections,observation has shown that Salix suchowensis Cheng was severely foraged by this leaf beetle while Salix triandra L.was damage free or only slightly damaged.Results of olfactometer bioassays show that the headspace volatiles from leaves of S.triandra significantly repelled adult beetles,suggesting that this species produces volatile repellents against P.versicolora.S.suchowensis had no effect on the beetles.Gas chromatography-mass spec-trometry was carried out to profile the headspace volatile organic compounds and 23 compounds from leaves of the alternate species in significantly different concentrations were detected.The effects of 20 chemical analogs on host discrimination were examined.Olfactory response to these chemicals showed that o-cymene,a S.suchowensis specific constituent,significantly attracted adult P.versicolora.In contrast,cis-3-hexenyl acetate,a constituent concentrated more in S.triandra than in S.suchowensis,significantly repelled beetles.Mixing o-cymene and cis-3-hexenyl acetate in comparable concentrations as in the volatiles of S.suchowensis demonstrated that the latter could mask the attracting effect of the former,causing a neutral response by adult beetles to leaves of S.suchowensis against clean air.In addition,chemical analogs have the same effect as plants when resembling volatile organic compounds in real samples.Two volatile metabolites were detected triggering host discrimination by one of the most damaging insect pests to host and non-host willows.The two metabolites are of considerable potential for use as olfactory signs in manag-ing the beetles.展开更多
Over the years, there has been a great deal of interest in developing artificial enzymesthat hydrolyse amide bond of peptides and proteins. Recently, we found that Pd(Ⅱ)complexes bind to the sulfur atom of S-methylcy...Over the years, there has been a great deal of interest in developing artificial enzymesthat hydrolyse amide bond of peptides and proteins. Recently, we found that Pd(Ⅱ)complexes bind to the sulfur atom of S-methylcysteine or methionine in peptides andpromote the selective hydrolysis of the adjacent amide bond on the carboxyl side of an-choring side chain. The half-lives of certain hydrolysis reactions are as short as展开更多
The brown planthopper （BPH, Nilaparvata lugens） is a destructive, monophagous, piercing-sucking insect pest of rice. Previous studies indicated that jasmonic acid （JA） positively regulates rice defense against che...The brown planthopper （BPH, Nilaparvata lugens） is a destructive, monophagous, piercing-sucking insect pest of rice. Previous studies indicated that jasmonic acid （JA） positively regulates rice defense against chewing insect pests but negatively regulates it against the piercing-sucking insect of BPH. We here demonstrated that overexpression of allene oxide cyclase （AOC） but not OPR3 （cis-12-oxo-phytodienoic acid （OPDA） reductase 3, an enzyme adjacent to AOC in the JA synthetic pathway） significantly increased rice resistance to BPH, mainly by reducing the feeding activity and survival rate. Further anal- ysis revealed that plant response to BPH under AOC overexpression was independent of the JA pathway and that significantly higher OPDA levels stimulated rice resistance to BPH. Microarray analysis identified multiple candidate resistance-related genes underAOCoverexpression. OPDA treatment stimulated the resistance of radish seedlings to green peach aphid Myzus persicae, another piercing-sucking insect. These results imply that rice resistance to chewing insects and to sucking insects can be enhanced simultaneously through AOC-mediated increases of JA and OPDA and provide direct evidence of the potential application of OPDA in stimulating plant defense responses to piercing-sucking insect pests in agriculture.展开更多
基金The authors wish to acknowledge financial support by the project of SINOPEC(No.223039).
文摘Utilizing solvent extraction to separate alkanes and olefins from catalytic light gasoline is an effective method for maximizing the utility of gasoline fractions.This study presents the determination of liquid-liquid equilibrium data for the ternary system of 1-hexene-n-hexane-3-methylsulfolane at 30℃,40℃,and 50℃under atmospheric pressure.The obtained data facilitated the construction of a ternary phase diagram for the system.The results showed that the extraction selectivity of 1-hexene/n-hexane exceeded 1.5 when using 3-methylsulfolane as the extraction solvent.Furthermore,the thermodynamic consistency of the experimental data was examined using Hand’s equation and the Othmer-Tobias method.The correlation coefficient,R^(2)≥0.9578,indicated the acceptable reliability of the phase equilibrium data.Subsequently,the NRTL(non-random two liquid)model was used to correlate the liquid-liquid phase equilibrium data and derive the binary interaction parameter.Notably,the results demonstrated that the root mean square deviation of the NRTL model correlation values from the experimental values did not exceed 2.5%.
文摘It is demonstrated that (3Z)-nonenal (NON) and (3Z)-hexenal (HEX) are oxidized in a cascade by lipoxygenase (LOX) and hydroperoxide peroxygenase (HP peroxygenase) into (2E)-4-hydroxy-2- nonenal (HNE) and (2E)-4-hydroxy-2-hexenal (HHE), respectively. In turn, HNE inactivates LOX terminating the cascade. The hydroxy-alkenals produced serve to inhibit plant pathogens, which initiated the cascade. In addition to LOX, other unknown oxygenases may be involved in the cascade.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.20271009,20231010,29992590-1)the Major State Basic Research Development Programs(Grant No.G2000078101)+1 种基金the Key Research Projection of the Foundation for University Key Teacherthe Scientific Research Foundation for the Returned Overseas Chinese Scholars by the Ministry of Education.
文摘Several methods including molecular mechanics, molecular dynamics, ONIOM that combines quantum chemistry with molecular mechanics and standard quantum chemistry are used to study the configuration and electron structures of an adduct of the DNA segment d(ATACATG*G*TACATA)·d(TATGTACCATGTAT) with cis-[Pt(NH3)(2-Picoline)]2+. The investigation shows that the configuration optimized by ONIOM is similar to that determined by NMR. Strong chemical bonds between Pt of the complex and two N7s of neighboring guanines in the DNA duplex and hydrogen bond between the NH3 of the complex and O6 of a nearby guanine have a large impact on the configuration of the adduct. Chemical bonds, the aforementioned hydrogen bond, and the interaction between a methyl of the complex and a methyl of the base in close proximity are critical for the complex to specifically recognize DNA.
基金The work was supported by the National Natural Science Foundation of China(grants 31570662 and 31500533)It was also enabled by the priority academic program development at Nanjing Forestry University.
文摘Plagiodera versicolora Laicharting is a highly damaging leaf beetle foraging on willow leaves.In willow germplasm collections,observation has shown that Salix suchowensis Cheng was severely foraged by this leaf beetle while Salix triandra L.was damage free or only slightly damaged.Results of olfactometer bioassays show that the headspace volatiles from leaves of S.triandra significantly repelled adult beetles,suggesting that this species produces volatile repellents against P.versicolora.S.suchowensis had no effect on the beetles.Gas chromatography-mass spec-trometry was carried out to profile the headspace volatile organic compounds and 23 compounds from leaves of the alternate species in significantly different concentrations were detected.The effects of 20 chemical analogs on host discrimination were examined.Olfactory response to these chemicals showed that o-cymene,a S.suchowensis specific constituent,significantly attracted adult P.versicolora.In contrast,cis-3-hexenyl acetate,a constituent concentrated more in S.triandra than in S.suchowensis,significantly repelled beetles.Mixing o-cymene and cis-3-hexenyl acetate in comparable concentrations as in the volatiles of S.suchowensis demonstrated that the latter could mask the attracting effect of the former,causing a neutral response by adult beetles to leaves of S.suchowensis against clean air.In addition,chemical analogs have the same effect as plants when resembling volatile organic compounds in real samples.Two volatile metabolites were detected triggering host discrimination by one of the most damaging insect pests to host and non-host willows.The two metabolites are of considerable potential for use as olfactory signs in manag-ing the beetles.
基金Project supported by the National Natural Science Foundation of China.
文摘Over the years, there has been a great deal of interest in developing artificial enzymesthat hydrolyse amide bond of peptides and proteins. Recently, we found that Pd(Ⅱ)complexes bind to the sulfur atom of S-methylcysteine or methionine in peptides andpromote the selective hydrolysis of the adjacent amide bond on the carboxyl side of an-choring side chain. The half-lives of certain hydrolysis reactions are as short as
基金This study was supported by the National Basic Research Program of China （2010CB126200） and the National Natural Science Foundation of China （31371949）.
文摘The brown planthopper （BPH, Nilaparvata lugens） is a destructive, monophagous, piercing-sucking insect pest of rice. Previous studies indicated that jasmonic acid （JA） positively regulates rice defense against chewing insect pests but negatively regulates it against the piercing-sucking insect of BPH. We here demonstrated that overexpression of allene oxide cyclase （AOC） but not OPR3 （cis-12-oxo-phytodienoic acid （OPDA） reductase 3, an enzyme adjacent to AOC in the JA synthetic pathway） significantly increased rice resistance to BPH, mainly by reducing the feeding activity and survival rate. Further anal- ysis revealed that plant response to BPH under AOC overexpression was independent of the JA pathway and that significantly higher OPDA levels stimulated rice resistance to BPH. Microarray analysis identified multiple candidate resistance-related genes underAOCoverexpression. OPDA treatment stimulated the resistance of radish seedlings to green peach aphid Myzus persicae, another piercing-sucking insect. These results imply that rice resistance to chewing insects and to sucking insects can be enhanced simultaneously through AOC-mediated increases of JA and OPDA and provide direct evidence of the potential application of OPDA in stimulating plant defense responses to piercing-sucking insect pests in agriculture.
