[Objective]The aim was to research the relationship and genetic diversity of Indocalamus.[Method]Using 13 samples of Indocalamus and 3 samples of Sasa as materials,the intergenic regions of trnL-trnF gene in chloropla...[Objective]The aim was to research the relationship and genetic diversity of Indocalamus.[Method]Using 13 samples of Indocalamus and 3 samples of Sasa as materials,the intergenic regions of trnL-trnF gene in chloroplast were amplified by PCR,and sequence analysis and phylogenetic trees construction were carried out.[Result]Using the universal primer,the intergenic regions of trnL-trnF were amplified,the lengths of the segments varied from 1 008 bp to 1 103 bp,of which 940 bp was compared.The dendrogram of trnL-trnF sequences showed that Indocalamus and Sasa were clustered together and they were homologous by 99%.All the samples were divided into five groups,the first group included 12 samples such as Indosalamus pedalis,I.pumilus,I.victorialis,I.longiauritus,I.tessellatus,Sasa sinica,Sasa pygmaea,I.barbatus,I.guangdongensis,I.herklotsii,I.Hirtivaginatus and S.fortunei.I.decorus,I.lacunosus,I.Latifolius and I.Migoi were respectively divided into four groups.[Conclusion]The high homology of all samples showed the low evolution speed and little information sites which suggested that the phylogeny of Indocalamus could not be well resolved by the intergenic region of trnL-trnF.展开更多
The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that t...The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that the concentration of Mo can be controlled by filter of the membrane in MBR and the toxicity of Mo to microorganism is decreased in the process of bioleaching.It was also evidenced that there were different leaching rates of Ni and Mo when the concentration of Mo was different.After leaching for 20 d in the MBR at Mo concentration of 395 mg/L,the leaching rates of Ni and Mo reached the maximum of 79.57% and 56.23% respectively under the conditions of 100 g/L of mineral density,65 ℃,pH=2 and 1.0 L/min of the aeration rate.While 75.59% Ni and 54.33% Mo were leached out in column without membrane under the same conditions.展开更多
Leaf morphogenesis requires the establishment of adaxlal-abaxlal polarity after primordium initiation from the snoot apical meristem (SAM). Several families of transcription factors are known to play critical roles ...Leaf morphogenesis requires the establishment of adaxlal-abaxlal polarity after primordium initiation from the snoot apical meristem (SAM). Several families of transcription factors are known to play critical roles in promoting adaxial or abaxial leaf fate. Recently, post-transcriptional gene silencing pathways have been shown to regulate the establishment of leaf polarity, providing novel and exciting insights into leaf development. For example, microRNAs (miR 165/166) and a trans-acting siRNA (TAS3-derived tasiR-ARF) have been shown to repress the expression of several key transcription factor genes. In addition, yet another level of regulation, post-translational regulation, has been revealed recently by studies on the role of the 26S proteasome in leaf polarity. Although our understanding regarding the molecular mecha- nisms underlying establishment of adaxial-abaxial polarity has greatly improved, there is still much that remains elusive. This review aims to discuss recent progress, as well as the remaining questions, regarding the molecular mechanisms underlying leaf polarity formation.展开更多
Nitrogen (N) was applied at rates of 0, 100, 200 and 300 kg.ha^-1 and boron (B) was applied as foliar at rates 0, 500 and 1000 g.ha^-1 to study the effect of different application rates of nitrogen and boron ferti...Nitrogen (N) was applied at rates of 0, 100, 200 and 300 kg.ha^-1 and boron (B) was applied as foliar at rates 0, 500 and 1000 g.ha^-1 to study the effect of different application rates of nitrogen and boron fertilizers on yield, yield components and fiber properties of cotton. Statistical results of study showed that N application significantly (P 〈 0.05) enhanced boll number, boll weight, seed cotton weight of boll, seed cotton yield and lint yield. Results of study also indicated that the maximum seed cotton yield was recorded in case of 200 kg.ha^-1 N application rate, and this application rate resulted in 19.6% increased seed cotton yield. Statistical results also indicated that foliar application of B significantly enhanced boll number, boll weight, seed cotton yield and lint yield. Results also demonstrated that the maximum seed cotton yield was obtained in case of 1000 g.hal foliar application of B, and this foliar application rate resulted in 25% increased seed cotton yield. Statistical results showed that effect of different application rates of N was not significant for all fiber properties (fiber length, fiber strength and fiber fineness). Conversely, results of study indicated that different application rates of B significantly affected some fiber properties.展开更多
To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples f...To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples from 20 species were collected and four methods of pH determination were used:refrigerated(stored at 4°C for 4 days),frozen(stored at−16°C for 4 days),oven-dried and fresh green-leaf pH(control).To explore the effects of different leaf:water mixing ratio on the pH determination results,we measured oven-dried green-leaf pH by leaf:water volume ratio of 1:8 and mass ratio of 1:10,and measured frozen senesced-leaf pH by mass ratio of 1:10 and 1:15.The standard major axis regression was used to analyze the relationship and the conversion equation between the measured pH with different methods.Foliar pH of refrigerated and frozen green leaves did not signifcantly differ from that of fresh green-leaf,but drying always overrated fresh green-leaf pH.During the feld sampling,cryopreservation with a portable refrigerator was an advisable choice to get a precise pH.For long-duration feld sampling,freezing was the optimal choice,and refrigeration is the best choice for the shorttime preservation.The different leaf:water mixing ratio signifcantly infuenced the measured foliar pH.High dilution reduced the proton concentration and increased the measured pH.Our fndings provide the conversion relationships between the existing pretreatment and measurement methods,and establish a connection among pH determined by different methods.Our study can facilitate foliar pH measurement,thus contributing to understanding of this interesting plant functional trait.展开更多
Aims Foliar pH of terrestrial plants,a trait tightly associated with plant physiology and nutrient utilization,varies with plant functional types(PFTs)and environmental changes.However,it is yet unclear about the vari...Aims Foliar pH of terrestrial plants,a trait tightly associated with plant physiology and nutrient utilization,varies with plant functional types(PFTs)and environmental changes.However,it is yet unclear about the variation in foliar pH of aquatic plants,and the difference between aquatic and terrestrial plants.Methods Foliar pH,leaf carbon,nitrogen content of plants along the lakeshore zones and the environmental conditions(water or soil pH,water status)of the corresponding vegetation of three small plateau lakes were investigated,to determine the variation and potential influence factors of foliar pH at both PFT and community levels.Important Findings Foliar pH varied largely among aquatic plants,and across aquatic,helophytic and terrestrial plants.Floating-leaved macrophytes had more acidic foliage(pH=4.21±0.05)than emergent(5.71±0.07)and submerged macrophytes(5.82±0.06).Foliar pH of aquatic herbs(5.43±0.10)was lower than that of helophytic(6.12±0.07)and terrestrial herbs(5.74±0.05).Terrestrial herbs had significantly higher foliar pH than woody plants.The variation in foliar pH across PFTs may be mainly ascribed to leaf structure,light utilization and nutrient characteristics.Consistent with the pattern on PFT level,aquatic communities had more acidic foliage than terrestrial communities,which was mainly shaped by species composition,water status and environmental pH.This study documented the first-time foliar pH of aquatic plants,and comparison of foliar pH among various plant types at a landscape scale.Our results provide bases for further exploration of the underlying mechanism and its ecological significance for wetland ecosystems.展开更多
Three kinds of leaf-surface waxes are extracted from the leaves of Euonymus japonicas(EJ), Sabina chinensis(SC) and Sabina procumbens(SP) to be tested for their tribological properties. Lubricating oils containing the...Three kinds of leaf-surface waxes are extracted from the leaves of Euonymus japonicas(EJ), Sabina chinensis(SC) and Sabina procumbens(SP) to be tested for their tribological properties. Lubricating oils containing these 3 waxes respectively were analyzed via gas chromatography-mass spectrometer(GC-MS) for their chemical constituents and tested with friction and wear testing machine and time of flight secondary ion mass spectrometry(TOF-SIMS) for the tribological mechanism. It was found that all the tested cuticular wax can reduce the coefficient of friction, and the waxes of SC and EJ can reduce the wear width. The contents of acid and esters in the wax can improve the friction reducing property by forming tribochemical films on the metal, but result in the increase of wear due to corrosion. The increase of ions containing C, H, O and the decline of aluminum positive ions on the worn surface,demonstrate that the tribofilms derived from long chain compounds play a role of protecting the metal surfaces.展开更多
Engineering the electronic properties of catalysts to target intermediate adsorption energy as well as harvest high selectivity represents a promising strategy to design advanced electrocatalysts for efficient CO_(2) ...Engineering the electronic properties of catalysts to target intermediate adsorption energy as well as harvest high selectivity represents a promising strategy to design advanced electrocatalysts for efficient CO_(2) electroreduction.Herein,a synergistical tuning on the electronic structure of the Cd Se nanorods is proposed for boosting electrochemical reduction of CO_(2) .The synergy of Ag doping coupled with Se vacancies tuned the electronic structure of the CdSe nanorods,which shows the metalloid characterization and thereby the accelerated electron transfer of CO_(2) electroreduction.Operando synchrotron radiation Fourier transform infrared spectroscopy and theoretical simulation revealed that the Ag doping and Se vacancies accelerated the CO_(2) activation process and lowered the energy barrier for the conversion from CO_(2) to;COOH;as a result,the performance of CO_(2) electroreduction was enhanced.The as-obtained metalloid Ag-doped CdSe nanorods exhibited a 2.7-fold increment in current density and 1.9-fold Faradaic efficiency of CO compared with the pristine CdSe nanorod.展开更多
For any Pisot number β it is known that the set F(β) ={t : limn→∞‖tβn‖ = 0} is countable, where ‖α‖ is the distance between a real number a and the set of integers. In this paper it is proved that every m...For any Pisot number β it is known that the set F(β) ={t : limn→∞‖tβn‖ = 0} is countable, where ‖α‖ is the distance between a real number a and the set of integers. In this paper it is proved that every member in this set is of the form cβn, where n is a nonnegative integer and e is determined by a linear system of equations. Furthermore, for some self-similar measures μ associated with β, the limit at infinity of the Fourier transforms limn→μ(tβn)≠0 if and only if t is in a certain subset of F(β). This generalizes a similar result of Huang and Strichartz.展开更多
基金the Supporting Program of the "Eleventh Five-year Plan" for Sci & Tech Research (2006BAD19B0202)The Programof Special Funds for basic scientific research of International Center for Bamboo and Rattan (1632009007)Foundation Item of International Center for Bamboo and Rattan (06 /07-C22)~~
文摘[Objective]The aim was to research the relationship and genetic diversity of Indocalamus.[Method]Using 13 samples of Indocalamus and 3 samples of Sasa as materials,the intergenic regions of trnL-trnF gene in chloroplast were amplified by PCR,and sequence analysis and phylogenetic trees construction were carried out.[Result]Using the universal primer,the intergenic regions of trnL-trnF were amplified,the lengths of the segments varied from 1 008 bp to 1 103 bp,of which 940 bp was compared.The dendrogram of trnL-trnF sequences showed that Indocalamus and Sasa were clustered together and they were homologous by 99%.All the samples were divided into five groups,the first group included 12 samples such as Indosalamus pedalis,I.pumilus,I.victorialis,I.longiauritus,I.tessellatus,Sasa sinica,Sasa pygmaea,I.barbatus,I.guangdongensis,I.herklotsii,I.Hirtivaginatus and S.fortunei.I.decorus,I.lacunosus,I.Latifolius and I.Migoi were respectively divided into four groups.[Conclusion]The high homology of all samples showed the low evolution speed and little information sites which suggested that the phylogeny of Indocalamus could not be well resolved by the intergenic region of trnL-trnF.
文摘The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that the concentration of Mo can be controlled by filter of the membrane in MBR and the toxicity of Mo to microorganism is decreased in the process of bioleaching.It was also evidenced that there were different leaching rates of Ni and Mo when the concentration of Mo was different.After leaching for 20 d in the MBR at Mo concentration of 395 mg/L,the leaching rates of Ni and Mo reached the maximum of 79.57% and 56.23% respectively under the conditions of 100 g/L of mineral density,65 ℃,pH=2 and 1.0 L/min of the aeration rate.While 75.59% Ni and 54.33% Mo were leached out in column without membrane under the same conditions.
基金supported by grants from the National Natural Science Foundation of China(Nos.30630041,90208009)the Ministry of Science and Technology of China(No.04JC14077)the Shanghai Scientific Committee(No.KSCX2-YW-N-016)to H Huang.
文摘Leaf morphogenesis requires the establishment of adaxlal-abaxlal polarity after primordium initiation from the snoot apical meristem (SAM). Several families of transcription factors are known to play critical roles in promoting adaxial or abaxial leaf fate. Recently, post-transcriptional gene silencing pathways have been shown to regulate the establishment of leaf polarity, providing novel and exciting insights into leaf development. For example, microRNAs (miR 165/166) and a trans-acting siRNA (TAS3-derived tasiR-ARF) have been shown to repress the expression of several key transcription factor genes. In addition, yet another level of regulation, post-translational regulation, has been revealed recently by studies on the role of the 26S proteasome in leaf polarity. Although our understanding regarding the molecular mecha- nisms underlying establishment of adaxial-abaxial polarity has greatly improved, there is still much that remains elusive. This review aims to discuss recent progress, as well as the remaining questions, regarding the molecular mechanisms underlying leaf polarity formation.
文摘Nitrogen (N) was applied at rates of 0, 100, 200 and 300 kg.ha^-1 and boron (B) was applied as foliar at rates 0, 500 and 1000 g.ha^-1 to study the effect of different application rates of nitrogen and boron fertilizers on yield, yield components and fiber properties of cotton. Statistical results of study showed that N application significantly (P 〈 0.05) enhanced boll number, boll weight, seed cotton weight of boll, seed cotton yield and lint yield. Results of study also indicated that the maximum seed cotton yield was recorded in case of 200 kg.ha^-1 N application rate, and this application rate resulted in 19.6% increased seed cotton yield. Statistical results also indicated that foliar application of B significantly enhanced boll number, boll weight, seed cotton yield and lint yield. Results also demonstrated that the maximum seed cotton yield was obtained in case of 1000 g.hal foliar application of B, and this foliar application rate resulted in 25% increased seed cotton yield. Statistical results showed that effect of different application rates of N was not significant for all fiber properties (fiber length, fiber strength and fiber fineness). Conversely, results of study indicated that different application rates of B significantly affected some fiber properties.
基金supported by the‘Strategic Priority Research Program’of the Chinese Academy of Sciences(XDA26040202)the National Natural Science Foundation of China(32001165)supported by Chinese Universities Scientifc Fund(2021TC117).
文摘To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples from 20 species were collected and four methods of pH determination were used:refrigerated(stored at 4°C for 4 days),frozen(stored at−16°C for 4 days),oven-dried and fresh green-leaf pH(control).To explore the effects of different leaf:water mixing ratio on the pH determination results,we measured oven-dried green-leaf pH by leaf:water volume ratio of 1:8 and mass ratio of 1:10,and measured frozen senesced-leaf pH by mass ratio of 1:10 and 1:15.The standard major axis regression was used to analyze the relationship and the conversion equation between the measured pH with different methods.Foliar pH of refrigerated and frozen green leaves did not signifcantly differ from that of fresh green-leaf,but drying always overrated fresh green-leaf pH.During the feld sampling,cryopreservation with a portable refrigerator was an advisable choice to get a precise pH.For long-duration feld sampling,freezing was the optimal choice,and refrigeration is the best choice for the shorttime preservation.The different leaf:water mixing ratio signifcantly infuenced the measured foliar pH.High dilution reduced the proton concentration and increased the measured pH.Our fndings provide the conversion relationships between the existing pretreatment and measurement methods,and establish a connection among pH determined by different methods.Our study can facilitate foliar pH measurement,thus contributing to understanding of this interesting plant functional trait.
基金This research was supported by the National Key Research and Development Program of China(2018YFC0507204)the National Natural Science Foundation of China(41473068,32001165).
文摘Aims Foliar pH of terrestrial plants,a trait tightly associated with plant physiology and nutrient utilization,varies with plant functional types(PFTs)and environmental changes.However,it is yet unclear about the variation in foliar pH of aquatic plants,and the difference between aquatic and terrestrial plants.Methods Foliar pH,leaf carbon,nitrogen content of plants along the lakeshore zones and the environmental conditions(water or soil pH,water status)of the corresponding vegetation of three small plateau lakes were investigated,to determine the variation and potential influence factors of foliar pH at both PFT and community levels.Important Findings Foliar pH varied largely among aquatic plants,and across aquatic,helophytic and terrestrial plants.Floating-leaved macrophytes had more acidic foliage(pH=4.21±0.05)than emergent(5.71±0.07)and submerged macrophytes(5.82±0.06).Foliar pH of aquatic herbs(5.43±0.10)was lower than that of helophytic(6.12±0.07)and terrestrial herbs(5.74±0.05).Terrestrial herbs had significantly higher foliar pH than woody plants.The variation in foliar pH across PFTs may be mainly ascribed to leaf structure,light utilization and nutrient characteristics.Consistent with the pattern on PFT level,aquatic communities had more acidic foliage than terrestrial communities,which was mainly shaped by species composition,water status and environmental pH.This study documented the first-time foliar pH of aquatic plants,and comparison of foliar pH among various plant types at a landscape scale.Our results provide bases for further exploration of the underlying mechanism and its ecological significance for wetland ecosystems.
基金supported by the National Natural Science Foundation of China(Grant No.51575181)Beijing Natural Science Foundation(Grant No.2172053)
文摘Three kinds of leaf-surface waxes are extracted from the leaves of Euonymus japonicas(EJ), Sabina chinensis(SC) and Sabina procumbens(SP) to be tested for their tribological properties. Lubricating oils containing these 3 waxes respectively were analyzed via gas chromatography-mass spectrometer(GC-MS) for their chemical constituents and tested with friction and wear testing machine and time of flight secondary ion mass spectrometry(TOF-SIMS) for the tribological mechanism. It was found that all the tested cuticular wax can reduce the coefficient of friction, and the waxes of SC and EJ can reduce the wear width. The contents of acid and esters in the wax can improve the friction reducing property by forming tribochemical films on the metal, but result in the increase of wear due to corrosion. The increase of ions containing C, H, O and the decline of aluminum positive ions on the worn surface,demonstrate that the tribofilms derived from long chain compounds play a role of protecting the metal surfaces.
基金supported by the National Natural Science Foundation of China(12025505 and 21873050)China Ministry of Science and Technology(2017YFA0208300)+1 种基金the Open Fund Project of State Key Laboratory of Environmentally Friendly Energy Materials(20KFHG08)the Youth Innovation Promotion Association CAS(CX2310007007 and CX2310000091)。
文摘Engineering the electronic properties of catalysts to target intermediate adsorption energy as well as harvest high selectivity represents a promising strategy to design advanced electrocatalysts for efficient CO_(2) electroreduction.Herein,a synergistical tuning on the electronic structure of the Cd Se nanorods is proposed for boosting electrochemical reduction of CO_(2) .The synergy of Ag doping coupled with Se vacancies tuned the electronic structure of the CdSe nanorods,which shows the metalloid characterization and thereby the accelerated electron transfer of CO_(2) electroreduction.Operando synchrotron radiation Fourier transform infrared spectroscopy and theoretical simulation revealed that the Ag doping and Se vacancies accelerated the CO_(2) activation process and lowered the energy barrier for the conversion from CO_(2) to;COOH;as a result,the performance of CO_(2) electroreduction was enhanced.The as-obtained metalloid Ag-doped CdSe nanorods exhibited a 2.7-fold increment in current density and 1.9-fold Faradaic efficiency of CO compared with the pristine CdSe nanorod.
文摘For any Pisot number β it is known that the set F(β) ={t : limn→∞‖tβn‖ = 0} is countable, where ‖α‖ is the distance between a real number a and the set of integers. In this paper it is proved that every member in this set is of the form cβn, where n is a nonnegative integer and e is determined by a linear system of equations. Furthermore, for some self-similar measures μ associated with β, the limit at infinity of the Fourier transforms limn→μ(tβn)≠0 if and only if t is in a certain subset of F(β). This generalizes a similar result of Huang and Strichartz.