A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to affo...A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to afford useful CF_3-containing intermediates in good yield.展开更多
The flux agents in common mould fluxes were fluoride and sodium oxide, which would do great harm to environments. B2O3 was selected as flux. The physical properties of B2O3-containing mould fluxes were studied. The co...The flux agents in common mould fluxes were fluoride and sodium oxide, which would do great harm to environments. B2O3 was selected as flux. The physical properties of B2O3-containing mould fluxes were studied. The corresponding physical properties of 37. 91% CAO-43.09% SiO2-5% Al2O3-5% MgO-2% Li20-7% B2O3 mould fluxes were as follows： the melting point was 909℃, the flowing temperature was 1 160℃, the viscosity and surface tension at 1300 ℃ were 0. 4 Pa · s and 0.32 N/m respectively, which could meet the demands for certain kinds of steels for mould fluxes in continuous casting.展开更多
Borosilicate glass with high rare earth content was fabricated by traditional method. The influence of glass compositions and rare earth content on absorption spectra was examined and discussed. With increasing Sm2O3 ...Borosilicate glass with high rare earth content was fabricated by traditional method. The influence of glass compositions and rare earth content on absorption spectra was examined and discussed. With increasing Sm2O3 content, the intensity of characteristic absorption peak is increased and the absorption peak is broadened. With increasing of the ratios of SiO2/B2O3 and Al2O3/SiO2, the broadening degree of absorption peak is increased. The experimental results provide basis for making special optical glasses which have the characteristics of high absorption for special wavelength laser and high transparence for visible light.展开更多
The Dissolving loss of Nd in the systems NdCl_3-MCl_n(M=Li,Na,K,Ca,Sr,Ba;n=1 or 2) and the NdCl_3-rich NdCl_3-LiF motlen salts,and in the system of NdCl_3-(90 wt% KCl,10 wt%MCl_n) was determined.It was found that the ...The Dissolving loss of Nd in the systems NdCl_3-MCl_n(M=Li,Na,K,Ca,Sr,Ba;n=1 or 2) and the NdCl_3-rich NdCl_3-LiF motlen salts,and in the system of NdCl_3-(90 wt% KCl,10 wt%MCl_n) was determined.It was found that the dissolving loss of Nd (B_(Nd)) in the NdCl_3-KCl,NdCl_3-CaCl_2 and NdCl_3-(90 wt%KCl,10 wt%CaCl_2) melts is rather insignificant.The dissolving loss of Nd in the NdCl_3-KCl system increases with temperature,yet it is only 1/3 of that in pure NdCl_3 when the content of NdCl_3 was less than 50 wt% in the mixture.Addition of LiF to NdCl_3 can diminish the dissolving loss of Nd.The nature of interaction between metallic Nd and its salts was also discussed.展开更多
The leaf is a major organ for photosynthesis,and its shape plays an important role in plant development and yield determination in rice(Oryza sativa L.).In this study,an adaxial curled leaf mutant,termed curly leaf 1-...The leaf is a major organ for photosynthesis,and its shape plays an important role in plant development and yield determination in rice(Oryza sativa L.).In this study,an adaxial curled leaf mutant,termed curly leaf 1-1(cul1-1),was obtained by chemical mutagenesis.The leaf rolling index of the cul1-1 mutant was higher than that of the wild-type,which was caused by the abnormal development of bulliform cells(BCs).We cloned the CUL1 gene by map-based cloning.A nonsense mutation was present in the cul1-1 mutant,converting a tryptophan codon into a stop codon.The CUL1 gene encodes a chromodomain,helicase/ATPase and DNA-binding domain containing protein.Genes related to leaf rolling and BC development,such as ADL1,REL1 and ROC5,were activated by the cul1-1 mutation.The trimethylation of lysine 27 in histone 3(H3K27me3),but not H3K4me3,at the ADL1,REL1 and ROC5 loci,was reduced in the cul1-1 mutant.High-throughput mRNA sequencing indicated that the cul1-1 mutation caused genome-wide differential gene expression.The differentially expressed genes were classified into a few gene ontology terms and Kyoto encyclopedia of genes and genomes pathways.In the natural population,22 missense genomic variations in the CUL1 locus were identified,which composed of 7 haplotypes.A haplotype network was also built with haplotype II as the ancestor.The findings revealed that CUL1 is essential for normal leaf development and regulates this process by inhibiting the expression of genes involved in leaf rolling and BC development.展开更多
Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2...Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2-dioxathiolane-2,2-dioxide(DTD),with the structure of sulfur surrounded by four oxygen atoms,have been proposed but less knowledge is available on the relationship between their molecular structures and interfacial stability.This work compares two similar molecule structure of cyclic sulfurcontaining additives,DTD and ethylene sulfite(ES),to investigate their effects on the electrochemical performance of NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM)||hard carbon(HC)pouch cells.Therein,ES with the structure of sulfur surrounded by three oxygen atoms,as electrolyte additive,is investigated in the SIBs for the first time.It is shown that adding 3.0%ES or 2.0%DTD(the optimal proportion)in the Control electrolyte(1 M NaPF_(6)in EC:EMC=3:7 with 5.0%FEC in weight)can improve cyclic stability and rate performance,respectively.Even under the high-temperature conditions,both ES and DTD exhibit good performance,but DTD is superior.Combinations of electrochemical methods,multi-spectroscopy,and theoretical calculations have been employed to evaluate and compare the effects of ES and DTD on sodium-ion battery.They reveal that ES and DTD can generate different content and composition by redox reaction on cathode and anode surface.The more and effective high-valence sulfur-containing components for DTD are the main reason to explain the better effect on DTD.This work shares new insights into the relationship between cyclic sulfur-containing additive molecule structure and electrolyte-electrode interface films effect,which fills the blanks of previous research.展开更多
α-(Trifluoromethyl)styrene and its derivatives have found wide applications in the fields of pharmaceuti-cals,agrochemicals,and advanced materials.They are also versatile trifluoromethyl-containing building blocks fo...α-(Trifluoromethyl)styrene and its derivatives have found wide applications in the fields of pharmaceuti-cals,agrochemicals,and advanced materials.They are also versatile trifluoromethyl-containing building blocks for the preparation of various trifluoromethyl-containing,fluorine-containing or nonfluorinated compounds.Recently,great efforts have been made to develop diverse reactions for rapidly accessing a wide range of valuable gem–difluoroalkenes and gem–difluoroalkylated compounds via defluorinative re-action or the defluorinative ipso-functionalization reaction ofα-(trifluoromethyl)styrenes,respectively.In contrast,α-(trifluoromethyl)styrenes remain notably underdeveloped with respect to their use in cycload-dition and hydroaddition reaction with retaining of three C–F bonds.This short review herein is aimed to summarize the recent progress on the cycloaddition and hydroaddition reaction including nucleophilic,radical and transition metal-catalyzed addition ofα-(trifluoromethyl)styrenes without accompanying de-fluorination.展开更多
基金This work was partially supported by the National Natural Science Foundation of China.
文摘A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to afford useful CF_3-containing intermediates in good yield.
基金Item Sponsored by National Natural Science Foundation of China (50474037) Jiangsu Province Natural Science Foundation forUniversity of China (04BJK430022)
文摘The flux agents in common mould fluxes were fluoride and sodium oxide, which would do great harm to environments. B2O3 was selected as flux. The physical properties of B2O3-containing mould fluxes were studied. The corresponding physical properties of 37. 91% CAO-43.09% SiO2-5% Al2O3-5% MgO-2% Li20-7% B2O3 mould fluxes were as follows： the melting point was 909℃, the flowing temperature was 1 160℃, the viscosity and surface tension at 1300 ℃ were 0. 4 Pa · s and 0.32 N/m respectively, which could meet the demands for certain kinds of steels for mould fluxes in continuous casting.
文摘Borosilicate glass with high rare earth content was fabricated by traditional method. The influence of glass compositions and rare earth content on absorption spectra was examined and discussed. With increasing Sm2O3 content, the intensity of characteristic absorption peak is increased and the absorption peak is broadened. With increasing of the ratios of SiO2/B2O3 and Al2O3/SiO2, the broadening degree of absorption peak is increased. The experimental results provide basis for making special optical glasses which have the characteristics of high absorption for special wavelength laser and high transparence for visible light.
文摘The Dissolving loss of Nd in the systems NdCl_3-MCl_n(M=Li,Na,K,Ca,Sr,Ba;n=1 or 2) and the NdCl_3-rich NdCl_3-LiF motlen salts,and in the system of NdCl_3-(90 wt% KCl,10 wt%MCl_n) was determined.It was found that the dissolving loss of Nd (B_(Nd)) in the NdCl_3-KCl,NdCl_3-CaCl_2 and NdCl_3-(90 wt%KCl,10 wt%CaCl_2) melts is rather insignificant.The dissolving loss of Nd in the NdCl_3-KCl system increases with temperature,yet it is only 1/3 of that in pure NdCl_3 when the content of NdCl_3 was less than 50 wt% in the mixture.Addition of LiF to NdCl_3 can diminish the dissolving loss of Nd.The nature of interaction between metallic Nd and its salts was also discussed.
基金supported by the National Natural Science Foundation of China(32070642 and 31371222 to Dr.Xiaoxue Wang)the National Key Research and Development Program from the Ministry of Science and Technology of China(2016YFD0100406 and 2017YFD0300107 to Dr.Xiaoxue Wang)the Science and Technology Department of Liaoning province(2022JH6/100100039 to Dr.Xiaoxue Wang)。
文摘The leaf is a major organ for photosynthesis,and its shape plays an important role in plant development and yield determination in rice(Oryza sativa L.).In this study,an adaxial curled leaf mutant,termed curly leaf 1-1(cul1-1),was obtained by chemical mutagenesis.The leaf rolling index of the cul1-1 mutant was higher than that of the wild-type,which was caused by the abnormal development of bulliform cells(BCs).We cloned the CUL1 gene by map-based cloning.A nonsense mutation was present in the cul1-1 mutant,converting a tryptophan codon into a stop codon.The CUL1 gene encodes a chromodomain,helicase/ATPase and DNA-binding domain containing protein.Genes related to leaf rolling and BC development,such as ADL1,REL1 and ROC5,were activated by the cul1-1 mutation.The trimethylation of lysine 27 in histone 3(H3K27me3),but not H3K4me3,at the ADL1,REL1 and ROC5 loci,was reduced in the cul1-1 mutant.High-throughput mRNA sequencing indicated that the cul1-1 mutation caused genome-wide differential gene expression.The differentially expressed genes were classified into a few gene ontology terms and Kyoto encyclopedia of genes and genomes pathways.In the natural population,22 missense genomic variations in the CUL1 locus were identified,which composed of 7 haplotypes.A haplotype network was also built with haplotype II as the ancestor.The findings revealed that CUL1 is essential for normal leaf development and regulates this process by inhibiting the expression of genes involved in leaf rolling and BC development.
基金supported by the National Natural Science Foundation of China(21875076)the Guangdong Provincial International Joint Research Center for Energy Storage Materials(2023A0505090009)the Science and Technology Planning Project of Guangzhou City(2023B03J1278)。
文摘Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2-dioxathiolane-2,2-dioxide(DTD),with the structure of sulfur surrounded by four oxygen atoms,have been proposed but less knowledge is available on the relationship between their molecular structures and interfacial stability.This work compares two similar molecule structure of cyclic sulfurcontaining additives,DTD and ethylene sulfite(ES),to investigate their effects on the electrochemical performance of NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM)||hard carbon(HC)pouch cells.Therein,ES with the structure of sulfur surrounded by three oxygen atoms,as electrolyte additive,is investigated in the SIBs for the first time.It is shown that adding 3.0%ES or 2.0%DTD(the optimal proportion)in the Control electrolyte(1 M NaPF_(6)in EC:EMC=3:7 with 5.0%FEC in weight)can improve cyclic stability and rate performance,respectively.Even under the high-temperature conditions,both ES and DTD exhibit good performance,but DTD is superior.Combinations of electrochemical methods,multi-spectroscopy,and theoretical calculations have been employed to evaluate and compare the effects of ES and DTD on sodium-ion battery.They reveal that ES and DTD can generate different content and composition by redox reaction on cathode and anode surface.The more and effective high-valence sulfur-containing components for DTD are the main reason to explain the better effect on DTD.This work shares new insights into the relationship between cyclic sulfur-containing additive molecule structure and electrolyte-electrode interface films effect,which fills the blanks of previous research.
基金support from the National Natural Science Foundation of China (No. 21472043)
文摘α-(Trifluoromethyl)styrene and its derivatives have found wide applications in the fields of pharmaceuti-cals,agrochemicals,and advanced materials.They are also versatile trifluoromethyl-containing building blocks for the preparation of various trifluoromethyl-containing,fluorine-containing or nonfluorinated compounds.Recently,great efforts have been made to develop diverse reactions for rapidly accessing a wide range of valuable gem–difluoroalkenes and gem–difluoroalkylated compounds via defluorinative re-action or the defluorinative ipso-functionalization reaction ofα-(trifluoromethyl)styrenes,respectively.In contrast,α-(trifluoromethyl)styrenes remain notably underdeveloped with respect to their use in cycload-dition and hydroaddition reaction with retaining of three C–F bonds.This short review herein is aimed to summarize the recent progress on the cycloaddition and hydroaddition reaction including nucleophilic,radical and transition metal-catalyzed addition ofα-(trifluoromethyl)styrenes without accompanying de-fluorination.
