Boron hydrides release an abundant amount of hydrogen in the presence of a suitable catalyst.Accelerating bimolecular activation kinetics is the key to designing cost-effective catalysts for borohydride hydrolysis.In ...Boron hydrides release an abundant amount of hydrogen in the presence of a suitable catalyst.Accelerating bimolecular activation kinetics is the key to designing cost-effective catalysts for borohydride hydrolysis.In this study,the bimolecular activation of a polar O-Co-P site demonstrated superior hydrogen-generation kinetics(turnover frequency,TOF=37 min−1,298 K)and low activation energy(41.0 kJ mol^(−1))close to that of noble-metal-based catalysts.Through a combination of experiments and theoretical calculations,it was revealed that the activated dangling oxygen atom in the Co–O precursor effectively replaced via surface-phosphorization because of strong electronic interactions between the dangling oxygen and P atoms.This substitution modulated the local coordination environment and electronegativity around the surface Co sites and formed a new polar O-Co-P active site for optimizing the activation kinetics of ammonia borane and water.This strategy based on bimolecular activation may create new avenues in the field of catalysis.展开更多
Mulliken, NPA, MK and CHelpG population analyses have been accomplished at the level of MP2/6-31G（d,p） for the title system. The variations of four kinds of charges on NH3 with intermolecular distance infer that ele...Mulliken, NPA, MK and CHelpG population analyses have been accomplished at the level of MP2/6-31G（d,p） for the title system. The variations of four kinds of charges on NH3 with intermolecular distance infer that electron transfers from NH3 to H2O. MK and CHelpG population analyses indicate more electron transfer than Mulliken and NPA ones. The atomic charges resulted from MK and CHelpG schemes infer that electron transfers from N in NH3 to H in H2O, which confirms that this bimolecular complex possesses linear structure as H3N…HOH.展开更多
Carbon dioxide reduction, as a sustainable and versatile strategy for the access of chemical fuels, has attracted increasing attention and enormous efforts have been devoted to it in recent years. However, employing c...Carbon dioxide reduction, as a sustainable and versatile strategy for the access of chemical fuels, has attracted increasing attention and enormous efforts have been devoted to it in recent years. However, employing carbon dioxide as double synthons via bimolecular reduction remains challenging. Here, by leveraging the bimolecular reduction of carbon dioxide to carbonyl and methyl respectively, we describe a Pd-catalyzed trifunctionalization of alkynes with aryl iodide for the first time and showcase its advantages on the formation of various β-diketones and their application in the constructing of heterocyclic compounds with important biological activity, including pyrimidine, oxazole, pyrazole.展开更多
The overestimation of the contaminant concentration is a main issue in simulating the reactive transport using the common advection-dispersion-reaction equation （ADRE）. To solve this problem, a new modeling method i...The overestimation of the contaminant concentration is a main issue in simulating the reactive transport using the common advection-dispersion-reaction equation （ADRE）. To solve this problem, a new modeling method is developed. The parameters of the model are identified based on experimental data. The results of the model are compared with previous results in the literature, and the sensitivity of the model is analyzed by examining the model＇s response to changes of the model parameters. Main conclusions are as follows： （1） The numerical modeling approach is feasible with an improved simulating accuracy. The predicted values are in agreement with the experimental measurements. The relative errors of the peak concentration between the simulated and experimental values are less than 2.5%. The errors are greatly reduced as compared with the results （about 67.8% as the maximum） based on a traditional ADRE in the literature. （2） There are three parameters （m, β0 and D ） which can be calibrated on the basis of experimental data in the model. The reactive product concentrations are mainly influenced by the parameters involved in the reactive ratio such as m and β0 The hydrodynamic dispersion coefficient D has almost no influence on the reactive product transport. （3） Our model does not provide better fitting curves for the ＂early arrival＂ and the ＂long tail＂. The ＂early arrival＂ and the ＂long tail＂ are associated with low values of the product AB. Under these conditions, the reaction rate is close to 0, and the model of the ADRE reduces to the advection-dispersion equation （ADE）. Further mechanism study is needed in the future.展开更多
The structures of 20 bimolecular triplexes have been built and simulated by molecular mechanics. The sequence of pyrimidine strand is 5′ dTTCTTTC L\-1TTTL\-5 CTTTTCTT 3′, where the five nucleotides underlined compos...The structures of 20 bimolecular triplexes have been built and simulated by molecular mechanics. The sequence of pyrimidine strand is 5′ dTTCTTTC L\-1TTTL\-5 CTTTTCTT 3′, where the five nucleotides underlined compose loop sequences. L\-1 and L\-5 represent varied residues. The sequences of purine strands are 5′ dGAAAAGAA 3′ and the reversed orientation 5′ dAAGAAAG 3′. The influence of different loop sequences and composition on the relative stability of twenty triplexes have been energetically analyzed. The results indicate that 5′ loop triplexes are more stable than 3′ loop ones and the stacking interaction of purines with their adjacent bases are stronger than that of pyrimidines. The stability of triplexes is mainly determined by the first and last nucleotides in the loop.展开更多
The accessory proteins(3a, 3b, 6, 7a, 7b, 8a, 8b, 9b and ORF14), predicted unknown proteins(PUPs) encoded by the genes, are considered to be unique to the severe acute respiratory syndrome coronavirus(SARS-Co V) genom...The accessory proteins(3a, 3b, 6, 7a, 7b, 8a, 8b, 9b and ORF14), predicted unknown proteins(PUPs) encoded by the genes, are considered to be unique to the severe acute respiratory syndrome coronavirus(SARS-Co V) genome. These proteins play important roles in various biological processes mediated by interactions with their partners. However, very little is known about the interactions among these accessory proteins. Here, a EYFP(enhanced yellow fluorescent protein) bimolecular fluorescence complementation(BiFC) assay was used to detect the interactions among accessory proteins. 33 out of 81 interactions were identified by BiFC, much more than that identified by the yeast two-hybrid(Y2H)system. This is the first report describing direct visualization of interactions among accessory proteins of SARS-CoV. These findings attest to the general applicability of the BiFC system for the verification of protein-protein interactions.展开更多
[目的]本文旨在揭示组蛋白乙酰转移酶GCN5(general control non-repressible 5)在葡萄生长发育过程中的调控机制,并筛选出与VvGCN5互作的蛋白,以期为进一步构建VvGCN5在葡萄生长发育中的调控网络提供理论基础。[方法]利用生物信息学技术...[目的]本文旨在揭示组蛋白乙酰转移酶GCN5(general control non-repressible 5)在葡萄生长发育过程中的调控机制,并筛选出与VvGCN5互作的蛋白,以期为进一步构建VvGCN5在葡萄生长发育中的调控网络提供理论基础。[方法]利用生物信息学技术对VvGCN5的蛋白二级结构、基因结构、功能域、启动子的顺式作用元件以及抗逆的表达量和时空表达进行分析,并在烟草中进行亚细胞定位,研究VvGCN5表达位置。通过酵母双杂交技术筛选与VvGCN5互作的蛋白,并通过双分子荧光互补(BIFC)技术进行验证。[结果]VvGCN5的二级结构由α-螺旋、延伸链、β-折叠以及无规则卷曲构成,含有10段内含子序列和11段CDS序列,具有Acetyltransf_1和Bromodomain结构域,以及ARE、GT1-motif、TGACG-motif、CAT-box、CGTCA-motif等顺式作用元件。通过查询GEO数据库发现VvGCN5可能受到光照和灰霉病的影响。VvGCN5主要表达于葡萄的成熟茎、萌芽初期、心皮、种子中。亚细胞定位发现VvGCN5位于细胞核和细胞膜上。此外,以pGBKT7-VvGCN5作为诱饵蛋白,通过酵母双杂交技术和双分子荧光互补技术发现8个阳性蛋白与VvGCN5互作。[结论]本研究鉴定并分析了VvGCN5的基本信息,并得到了8个与VvGCN5互作的蛋白。展开更多
基金H.Z.and K.Z.contributed equally to this work.Financial supports from the National Natural Science Foundation of China (nos.22075254,52071135,51871090,U1804135,21805071,51671080,and 21401168)Plan for Scientific Inno-vation Talent of Henan Province (no.194200510019)Key Project of Educa-tional Commission of Henan Province (no.19A150025)are acknowledged.
文摘Boron hydrides release an abundant amount of hydrogen in the presence of a suitable catalyst.Accelerating bimolecular activation kinetics is the key to designing cost-effective catalysts for borohydride hydrolysis.In this study,the bimolecular activation of a polar O-Co-P site demonstrated superior hydrogen-generation kinetics(turnover frequency,TOF=37 min−1,298 K)and low activation energy(41.0 kJ mol^(−1))close to that of noble-metal-based catalysts.Through a combination of experiments and theoretical calculations,it was revealed that the activated dangling oxygen atom in the Co–O precursor effectively replaced via surface-phosphorization because of strong electronic interactions between the dangling oxygen and P atoms.This substitution modulated the local coordination environment and electronegativity around the surface Co sites and formed a new polar O-Co-P active site for optimizing the activation kinetics of ammonia borane and water.This strategy based on bimolecular activation may create new avenues in the field of catalysis.
基金the National Science Foundation (29773021) and Provisional Educational Foundation of Jiangsu (98KJB150001).
文摘Mulliken, NPA, MK and CHelpG population analyses have been accomplished at the level of MP2/6-31G（d,p） for the title system. The variations of four kinds of charges on NH3 with intermolecular distance infer that electron transfers from NH3 to H2O. MK and CHelpG population analyses indicate more electron transfer than Mulliken and NPA ones. The atomic charges resulted from MK and CHelpG schemes infer that electron transfers from N in NH3 to H in H2O, which confirms that this bimolecular complex possesses linear structure as H3N…HOH.
基金supported by the National Natural Science Foundation of China(21971073,22001075,22231002)the Natural Science Foundation of Guangdong Province(2019A1515011468)+2 种基金the Discipline Construction Project of Guangdong Medical University(4SG23231G,4SG23249G)the Ordinary University Characteristic Innovation Project of Guangdong Province(2022KTSCX047)the Key-Area Research and Development Program of Guangdong Province(2020B010188001)。
文摘Carbon dioxide reduction, as a sustainable and versatile strategy for the access of chemical fuels, has attracted increasing attention and enormous efforts have been devoted to it in recent years. However, employing carbon dioxide as double synthons via bimolecular reduction remains challenging. Here, by leveraging the bimolecular reduction of carbon dioxide to carbonyl and methyl respectively, we describe a Pd-catalyzed trifunctionalization of alkynes with aryl iodide for the first time and showcase its advantages on the formation of various β-diketones and their application in the constructing of heterocyclic compounds with important biological activity, including pyrimidine, oxazole, pyrazole.
基金supported by the National Natural Science Foundation of China(Grant Nos.41372245,41272251)
文摘The overestimation of the contaminant concentration is a main issue in simulating the reactive transport using the common advection-dispersion-reaction equation （ADRE）. To solve this problem, a new modeling method is developed. The parameters of the model are identified based on experimental data. The results of the model are compared with previous results in the literature, and the sensitivity of the model is analyzed by examining the model＇s response to changes of the model parameters. Main conclusions are as follows： （1） The numerical modeling approach is feasible with an improved simulating accuracy. The predicted values are in agreement with the experimental measurements. The relative errors of the peak concentration between the simulated and experimental values are less than 2.5%. The errors are greatly reduced as compared with the results （about 67.8% as the maximum） based on a traditional ADRE in the literature. （2） There are three parameters （m, β0 and D ） which can be calibrated on the basis of experimental data in the model. The reactive product concentrations are mainly influenced by the parameters involved in the reactive ratio such as m and β0 The hydrodynamic dispersion coefficient D has almost no influence on the reactive product transport. （3） Our model does not provide better fitting curves for the ＂early arrival＂ and the ＂long tail＂. The ＂early arrival＂ and the ＂long tail＂ are associated with low values of the product AB. Under these conditions, the reaction rate is close to 0, and the model of the ADRE reduces to the advection-dispersion equation （ADE）. Further mechanism study is needed in the future.
文摘The structures of 20 bimolecular triplexes have been built and simulated by molecular mechanics. The sequence of pyrimidine strand is 5′ dTTCTTTC L\-1TTTL\-5 CTTTTCTT 3′, where the five nucleotides underlined compose loop sequences. L\-1 and L\-5 represent varied residues. The sequences of purine strands are 5′ dGAAAAGAA 3′ and the reversed orientation 5′ dAAGAAAG 3′. The influence of different loop sequences and composition on the relative stability of twenty triplexes have been energetically analyzed. The results indicate that 5′ loop triplexes are more stable than 3′ loop ones and the stacking interaction of purines with their adjacent bases are stronger than that of pyrimidines. The stability of triplexes is mainly determined by the first and last nucleotides in the loop.
基金supported by National Natural Science Foundation of China (No. 81072673)
文摘The accessory proteins(3a, 3b, 6, 7a, 7b, 8a, 8b, 9b and ORF14), predicted unknown proteins(PUPs) encoded by the genes, are considered to be unique to the severe acute respiratory syndrome coronavirus(SARS-Co V) genome. These proteins play important roles in various biological processes mediated by interactions with their partners. However, very little is known about the interactions among these accessory proteins. Here, a EYFP(enhanced yellow fluorescent protein) bimolecular fluorescence complementation(BiFC) assay was used to detect the interactions among accessory proteins. 33 out of 81 interactions were identified by BiFC, much more than that identified by the yeast two-hybrid(Y2H)system. This is the first report describing direct visualization of interactions among accessory proteins of SARS-CoV. These findings attest to the general applicability of the BiFC system for the verification of protein-protein interactions.
文摘[目的]本文旨在揭示组蛋白乙酰转移酶GCN5(general control non-repressible 5)在葡萄生长发育过程中的调控机制,并筛选出与VvGCN5互作的蛋白,以期为进一步构建VvGCN5在葡萄生长发育中的调控网络提供理论基础。[方法]利用生物信息学技术对VvGCN5的蛋白二级结构、基因结构、功能域、启动子的顺式作用元件以及抗逆的表达量和时空表达进行分析,并在烟草中进行亚细胞定位,研究VvGCN5表达位置。通过酵母双杂交技术筛选与VvGCN5互作的蛋白,并通过双分子荧光互补(BIFC)技术进行验证。[结果]VvGCN5的二级结构由α-螺旋、延伸链、β-折叠以及无规则卷曲构成,含有10段内含子序列和11段CDS序列,具有Acetyltransf_1和Bromodomain结构域,以及ARE、GT1-motif、TGACG-motif、CAT-box、CGTCA-motif等顺式作用元件。通过查询GEO数据库发现VvGCN5可能受到光照和灰霉病的影响。VvGCN5主要表达于葡萄的成熟茎、萌芽初期、心皮、种子中。亚细胞定位发现VvGCN5位于细胞核和细胞膜上。此外,以pGBKT7-VvGCN5作为诱饵蛋白,通过酵母双杂交技术和双分子荧光互补技术发现8个阳性蛋白与VvGCN5互作。[结论]本研究鉴定并分析了VvGCN5的基本信息,并得到了8个与VvGCN5互作的蛋白。
