The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application dose.However,the molecular mechanisms that lead to those results have yet to be elucidated....The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application dose.However,the molecular mechanisms that lead to those results have yet to be elucidated.The aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane bagasse biochar on soybean germination.Three types of biochars were prepared by pyrolysis at 300℃(SCB300),400℃(SCB400)and 600℃(SCB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,respectively.The experiment was performed in 8 days of incubation,when the number of germinated seeds and the average radicle length were determined.To evaluate the metabolome,the dry biomass(DB)was subjected to extraction with a mixture of methanol-d4 and D2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear Magnetic Resonance.The Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to control.On the other hand,the DB increased in all treatments,except for SCB300,at doses of 1%and 3%w/w.Seven metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in DB extracts as the most influential finding for the separation of treatments.Taken together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.展开更多
Elastomer blends,among which natural rubber(NR)and butadiene rubber(BR),are involved in many components of the automotive/tire industry.A comprehensive understanding of their mechanical behavior requires,among other f...Elastomer blends,among which natural rubber(NR)and butadiene rubber(BR),are involved in many components of the automotive/tire industry.A comprehensive understanding of their mechanical behavior requires,among other features,a detailed description of the crosslink density in these mixtures.In the case of vulcanized immiscible blends,the distribution of the cross-link density within each of the NR-and BR-rich domains is key information,but difficult to determine using the conventional approaches used for one-component crosslinked elastomers.In this study,the vulcanization within NR/BR blends is investigated using a robust^(1)H double-quantum(DQ)MAS recoupling experiment,BaBa-xy16.Two kinds of cross-linked NR/BR blends were considered with two different microstructures for the BR component.The bulk organization of the resulting blends was first probed by analyzing the^(1)H spin-lattice relaxation behavior.In a second step,BaBa-xy16 was used to investigate,in a selective way,the cross-link heterogeneities within NR/BR blends.In particular,for immiscible NR/BR mixtures,the distribution of the cross-link density between both phases was compared and the observed differences were discussed.展开更多
The rhodium-phosphine complex catalyst Rh(CO)(acac)(PPh3)(Ⅰ) for 1-hexene hydroformylation was studied under the following reaction conditions: CO/H2=1(mole rate), pressure 1.0 MPa, temperature 25-120℃, by using the...The rhodium-phosphine complex catalyst Rh(CO)(acac)(PPh3)(Ⅰ) for 1-hexene hydroformylation was studied under the following reaction conditions: CO/H2=1(mole rate), pressure 1.0 MPa, temperature 25-120℃, by using the pres surized in-situ 1H NMR technique. Experimental results indicated that the formation of a rhodium hydride complex from (Ⅰ) began at room temperature and its amount increased with increasing of reaction temperature. This intermediate complex began to decompose at 100℃ and disapeared completely at 120℃ The intensity change of the proton signal was parallel to catalytical activity in hydroformylation of olefins. Under pure CO pressure the proton signal of Rh-H bond was not observed. There was a 0.2 ppm difference in proton chemical shifts of Rh-H bond under pure H2 pressure and under H2+CO pressure. The results showed that the rhodium-hydride carbonyl complex is the active intermediate in the industrial hydroformylation process.展开更多
The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical an...The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical and chemical properties,these compounds are difficult to be identified by gas chromatography(GC)without standard samples.With the development of modern nuclear magnetic resonance(NMR)techniques,NMR has emerged as a powerful and efficient tool for the rapid analysis of complex and crude mixtures without purification.In this study,the parameters of one-dimensional(1D)total correlation spectroscopy(TOCSY)NMR techniques,including 1D selective gradient TOCSY and 1D chemicalshift-selective filtration(CSSF)with TOCSY,were optimized to obtain comprehensive molecular structure information.The results indicate that the overlapped signals in NMR spectra of nonpolar aromatic compounds(including o-xylene,m-xylene,p-xylene and ethylbenzene),polar aromatic compounds(benzyl alcohol,benzaldehyde,benzoic acid),and aromatic compounds with additional conjugated bonds(styrene)can be resolved in 1D TOCSY.More importantly,full molecular structures can be clearly distinguished by setting appropriate mixing time in 1D TOCSY.This approach simplifies the NMR spectra,provides structural information of entire molecules,and can be applied for the analysis of other structural isomers.展开更多
An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and 8...An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and 8.0Hz.Furthermore,the ^(1)H(proton)nuclear magnetic resonance(NMR)pattern of phenolic hydroxyl protons was developed as a“diagnosis signal”to ascertain the relative location of each side chain in DMSO-d_(6) at sample concentrations of 0.022-0.034 mol/L.The chemical shift differences of 0.6ppm between OH-5' and OH-1 and between OH-8'and OH-4 are assigned to Type A and Type B,respectively.All reported ambiguous structures were corrected by this pattern.Additionally,the steric structures of isolated compounds were elucidated by quantum chemical calculations of electronic circular dichroism(ECD)spectra.展开更多
Bioremediation is an eco-compatible and economical approach to counter textile dye menace. The isolated Lentinus squarrosulus AF5 was assessed for decolourization of textile azo dyes, and had shown ~93%, 88% and 70% d...Bioremediation is an eco-compatible and economical approach to counter textile dye menace. The isolated Lentinus squarrosulus AF5 was assessed for decolourization of textile azo dyes, and had shown ~93%, 88% and 70% decolorization of Reactive blue 160 (RB160), Reactive black 5 (RB5) and Amido black 10B (AB10B) respectively. Further analysis using UV-vis, HPLC, and FTIR, <sup>1</sup>H NMR had shown the degradation of the dyes. Toxicity analysis of the metabolites was performed using seed germination and plant growth on two agriculturally important plants Guar (Cyamopsis tetragonoloba) and wheat (Triticum aestivum) as well as cytotoxicity analysis using the human keratinocyte cell line (HaCaT). The dye mix appeared inhibitory for seed germination (20% - 40%), whereas metabolites were non-inhibitory for germination. Treatment of HaCaT cells with of dye mix and metabolites led into 45% and ~100% of cell viability of HaCaT cells respectively. Therefore, metabolites following degradation of the dye mix were observed to be non-toxic.展开更多
CO_(2) huff-n-puff shows great potential to promote shale oil recovery after primary depletion.However,the extracting process of shale oil residing in different types of pores induced by the injected CO_(2) remains un...CO_(2) huff-n-puff shows great potential to promote shale oil recovery after primary depletion.However,the extracting process of shale oil residing in different types of pores induced by the injected CO_(2) remains unclear.Moreover,how to saturate shale core samples with oil is still an experimental challenge,and needs a recommended procedure.These issues significantly impede probing CO_(2) huff-n-puff in extracting shale oil as a means of enhanced oil recovery(EOR)processes.In this paper,the oil saturation process of shale core samples and their CO_(2) extraction response with respect to pore types were investigated using online T1-T2nuclear magnetic resonance(NMR)spectroscopy.The results indicated that the oil saturation of shale core samples rapidly increased in the first 16 days under the conditions of 60℃and 30 MPa and then tended to plateau.The maximum oil saturation could reach 46.2%after a vacuum and pressurization duration of 20 days.After saturation,three distinct regions were identified on the T1-T2NMR spectra of the shale core samples,corresponding to kerogen,organic pores(OPs),and inorganic pores(IPs),respectively.The oil trapped in IPs was the primary target for CO_(2) huff-n-puff in shale with a maximum cumulative oil recovery(COR)of 70%original oil in place(OOIP)after three cycles,while the oil trapped in OPs and kerogen presented challenges for extraction(COR<24.2%OOIP in OPs and almost none for kerogen).CO_(2) preferentially extracted the accessible oil trapped in large IPs,while due to the tiny pores and strong affinity of oil-wet walls,the oil saturated in OPs mainly existed in an adsorbed state,leading to an insignificant COR.Furthermore,COR demonstrated a linear increasing tendency with soaking pressure,even when the pressure noticeably exceeded the minimum miscible pressure,implying that the formation of a miscible phase between CO_(2) and oil was not the primary drive for CO_(2) huff-n-puff in shale.展开更多
The recycled oil from coal liquefaction was separated into three fractions(saturates,aromatics and polar fraction) by liquid chromatograph according to group composition.Each fraction was analyzed qualitatively by 1H-...The recycled oil from coal liquefaction was separated into three fractions(saturates,aromatics and polar fraction) by liquid chromatograph according to group composition.Each fraction was analyzed qualitatively by 1H-NMR spectra,then the aromatic fraction was characterized using gas chromatograph/mass spectrometer(GC-MS).It shows that liquid chromatograph is well used to separate coal liquefaction oil with high repeatability and high recovery yield.Aromatic fraction with carbon number from C10 to C21 mainly includes dicyclic-,tricyclic-and tetracyclic-hydrogenation aromatic compounds such as tetrahydronaphthalene,hydrophenanthrene,hydropyrene and their alkyl substitution compounds and so on.展开更多
基金Fundacao Coordenacao de Aperfeicoamento de Pessoal de Nível Superior (CAPES), Fundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG [grant number APQ-02349-21])Universidade do Estado de Minas Gerais (UEMG [Productivity Researcher of the UEMG – PQ/UEMG]) for their financial support and fellowships
文摘The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application dose.However,the molecular mechanisms that lead to those results have yet to be elucidated.The aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane bagasse biochar on soybean germination.Three types of biochars were prepared by pyrolysis at 300℃(SCB300),400℃(SCB400)and 600℃(SCB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,respectively.The experiment was performed in 8 days of incubation,when the number of germinated seeds and the average radicle length were determined.To evaluate the metabolome,the dry biomass(DB)was subjected to extraction with a mixture of methanol-d4 and D2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear Magnetic Resonance.The Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to control.On the other hand,the DB increased in all treatments,except for SCB300,at doses of 1%and 3%w/w.Seven metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in DB extracts as the most influential finding for the separation of treatments.Taken together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.
基金financial support from the French National Research Agency(ANR)[grant number ANR-22-CE06-0031]。
文摘Elastomer blends,among which natural rubber(NR)and butadiene rubber(BR),are involved in many components of the automotive/tire industry.A comprehensive understanding of their mechanical behavior requires,among other features,a detailed description of the crosslink density in these mixtures.In the case of vulcanized immiscible blends,the distribution of the cross-link density within each of the NR-and BR-rich domains is key information,but difficult to determine using the conventional approaches used for one-component crosslinked elastomers.In this study,the vulcanization within NR/BR blends is investigated using a robust^(1)H double-quantum(DQ)MAS recoupling experiment,BaBa-xy16.Two kinds of cross-linked NR/BR blends were considered with two different microstructures for the BR component.The bulk organization of the resulting blends was first probed by analyzing the^(1)H spin-lattice relaxation behavior.In a second step,BaBa-xy16 was used to investigate,in a selective way,the cross-link heterogeneities within NR/BR blends.In particular,for immiscible NR/BR mixtures,the distribution of the cross-link density between both phases was compared and the observed differences were discussed.
文摘The rhodium-phosphine complex catalyst Rh(CO)(acac)(PPh3)(Ⅰ) for 1-hexene hydroformylation was studied under the following reaction conditions: CO/H2=1(mole rate), pressure 1.0 MPa, temperature 25-120℃, by using the pres surized in-situ 1H NMR technique. Experimental results indicated that the formation of a rhodium hydride complex from (Ⅰ) began at room temperature and its amount increased with increasing of reaction temperature. This intermediate complex began to decompose at 100℃ and disapeared completely at 120℃ The intensity change of the proton signal was parallel to catalytical activity in hydroformylation of olefins. Under pure CO pressure the proton signal of Rh-H bond was not observed. There was a 0.2 ppm difference in proton chemical shifts of Rh-H bond under pure H2 pressure and under H2+CO pressure. The results showed that the rhodium-hydride carbonyl complex is the active intermediate in the industrial hydroformylation process.
基金We thank the Natural Science Foundation of Shanxi Province(202103021224439)National Natural Science Foundation of China(22075308)for financial support.
文摘The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of applications.However,because of similar physical and chemical properties,these compounds are difficult to be identified by gas chromatography(GC)without standard samples.With the development of modern nuclear magnetic resonance(NMR)techniques,NMR has emerged as a powerful and efficient tool for the rapid analysis of complex and crude mixtures without purification.In this study,the parameters of one-dimensional(1D)total correlation spectroscopy(TOCSY)NMR techniques,including 1D selective gradient TOCSY and 1D chemicalshift-selective filtration(CSSF)with TOCSY,were optimized to obtain comprehensive molecular structure information.The results indicate that the overlapped signals in NMR spectra of nonpolar aromatic compounds(including o-xylene,m-xylene,p-xylene and ethylbenzene),polar aromatic compounds(benzyl alcohol,benzaldehyde,benzoic acid),and aromatic compounds with additional conjugated bonds(styrene)can be resolved in 1D TOCSY.More importantly,full molecular structures can be clearly distinguished by setting appropriate mixing time in 1D TOCSY.This approach simplifies the NMR spectra,provides structural information of entire molecules,and can be applied for the analysis of other structural isomers.
基金funded by the CAMS Innovation Fund for Medical Sciences(CIFMS,No.2021-I2M-1-028).
文摘An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and 8.0Hz.Furthermore,the ^(1)H(proton)nuclear magnetic resonance(NMR)pattern of phenolic hydroxyl protons was developed as a“diagnosis signal”to ascertain the relative location of each side chain in DMSO-d_(6) at sample concentrations of 0.022-0.034 mol/L.The chemical shift differences of 0.6ppm between OH-5' and OH-1 and between OH-8'and OH-4 are assigned to Type A and Type B,respectively.All reported ambiguous structures were corrected by this pattern.Additionally,the steric structures of isolated compounds were elucidated by quantum chemical calculations of electronic circular dichroism(ECD)spectra.
文摘Bioremediation is an eco-compatible and economical approach to counter textile dye menace. The isolated Lentinus squarrosulus AF5 was assessed for decolourization of textile azo dyes, and had shown ~93%, 88% and 70% decolorization of Reactive blue 160 (RB160), Reactive black 5 (RB5) and Amido black 10B (AB10B) respectively. Further analysis using UV-vis, HPLC, and FTIR, <sup>1</sup>H NMR had shown the degradation of the dyes. Toxicity analysis of the metabolites was performed using seed germination and plant growth on two agriculturally important plants Guar (Cyamopsis tetragonoloba) and wheat (Triticum aestivum) as well as cytotoxicity analysis using the human keratinocyte cell line (HaCaT). The dye mix appeared inhibitory for seed germination (20% - 40%), whereas metabolites were non-inhibitory for germination. Treatment of HaCaT cells with of dye mix and metabolites led into 45% and ~100% of cell viability of HaCaT cells respectively. Therefore, metabolites following degradation of the dye mix were observed to be non-toxic.
基金the financial support of National Key Research and Development Program of China(2023YFE0120700)National Natural Science Foundation of China(52274041)Distinguished Young Sichuan Science Scholars(2023NSFSC1954)。
文摘CO_(2) huff-n-puff shows great potential to promote shale oil recovery after primary depletion.However,the extracting process of shale oil residing in different types of pores induced by the injected CO_(2) remains unclear.Moreover,how to saturate shale core samples with oil is still an experimental challenge,and needs a recommended procedure.These issues significantly impede probing CO_(2) huff-n-puff in extracting shale oil as a means of enhanced oil recovery(EOR)processes.In this paper,the oil saturation process of shale core samples and their CO_(2) extraction response with respect to pore types were investigated using online T1-T2nuclear magnetic resonance(NMR)spectroscopy.The results indicated that the oil saturation of shale core samples rapidly increased in the first 16 days under the conditions of 60℃and 30 MPa and then tended to plateau.The maximum oil saturation could reach 46.2%after a vacuum and pressurization duration of 20 days.After saturation,three distinct regions were identified on the T1-T2NMR spectra of the shale core samples,corresponding to kerogen,organic pores(OPs),and inorganic pores(IPs),respectively.The oil trapped in IPs was the primary target for CO_(2) huff-n-puff in shale with a maximum cumulative oil recovery(COR)of 70%original oil in place(OOIP)after three cycles,while the oil trapped in OPs and kerogen presented challenges for extraction(COR<24.2%OOIP in OPs and almost none for kerogen).CO_(2) preferentially extracted the accessible oil trapped in large IPs,while due to the tiny pores and strong affinity of oil-wet walls,the oil saturated in OPs mainly existed in an adsorbed state,leading to an insignificant COR.Furthermore,COR demonstrated a linear increasing tendency with soaking pressure,even when the pressure noticeably exceeded the minimum miscible pressure,implying that the formation of a miscible phase between CO_(2) and oil was not the primary drive for CO_(2) huff-n-puff in shale.
文摘The recycled oil from coal liquefaction was separated into three fractions(saturates,aromatics and polar fraction) by liquid chromatograph according to group composition.Each fraction was analyzed qualitatively by 1H-NMR spectra,then the aromatic fraction was characterized using gas chromatograph/mass spectrometer(GC-MS).It shows that liquid chromatograph is well used to separate coal liquefaction oil with high repeatability and high recovery yield.Aromatic fraction with carbon number from C10 to C21 mainly includes dicyclic-,tricyclic-and tetracyclic-hydrogenation aromatic compounds such as tetrahydronaphthalene,hydrophenanthrene,hydropyrene and their alkyl substitution compounds and so on.
