Motivated by the study of regularization for sparse problems,we propose a new regularization method for sparse vector recovery.We derive sufficient conditions on the well-posedness of the new regularization,and design...Motivated by the study of regularization for sparse problems,we propose a new regularization method for sparse vector recovery.We derive sufficient conditions on the well-posedness of the new regularization,and design an iterative algorithm,namely the iteratively reweighted algorithm(IR-algorithm),for efficiently computing the sparse solutions to the proposed regularization model.The convergence of the IR-algorithm and the setting of the regularization parameters are analyzed at length.Finally,we present numerical examples to illustrate the features of the new regularization and algorithm.展开更多
Background:Lung cancer is one of the most lethal cancers worldwide,but studies have shown that the higher the expression of programmed cell death protein 1 ligand 1(PD-L1)in non-small cell lung cancer(NSCLC),the more ...Background:Lung cancer is one of the most lethal cancers worldwide,but studies have shown that the higher the expression of programmed cell death protein 1 ligand 1(PD-L1)in non-small cell lung cancer(NSCLC),the more likely it will benefit from anti-PD-L1 immunotherapy.The purpose of our study was to collect and analyze abundant clinical samples in order to provide evidence for clinicians and patients who might consider anti-PD-L1 immunotherapy while jointly formulating treatment plans.Methods:On the one hand,we obtained cases from The Cancer Genome Atlas(TCGA)database,including 498 lung squamous cell cancer(LUSC)patients and 515 lung adenocarcinoma(LUAD)patients.We studied the lung caner driver gene in LUSC and LUAD.On the other hand,PD-L1 expression was detected in lung cancer tissues of 1,008 NSCLC patients with immunohistochemistry staining(IHC),and we studied the correlation between PD-L1 protein expression and clinicopathological characteristics.Results:PD-L1 expression was higher in LUSC than in LUAD at the mRNA level.In univariate analysis,PD-L1 expression at the protein level was higher in patients who were males,were LUSC,were smokers,had a tumor diameter>3 cm,had poor differentiation,or had stages Ⅲ-Ⅳ disease.In multivariate analysis,PD-L1 expression was higher in patients who were LUSC or in poor differentiation.Conclusion:In term of protein level,PD-L1 expression was higher in NSCLC patients who were LUSC or in poor differentiation.We recommend that PD-L1 IHC detection can be routinely performed in such populations that are likely to benefit most from PD-L1 immunotherapy.展开更多
Due to the influence of deep-sea environment,deep-sea sediments are usually heterogeneous,and their moduli of elasticity and density change as depth changes.Combined with the characteristics of deep-sea sediments,the ...Due to the influence of deep-sea environment,deep-sea sediments are usually heterogeneous,and their moduli of elasticity and density change as depth changes.Combined with the characteristics of deep-sea sediments,the thermo-hydro-mechanical coupling dynamic response model of heterogeneous saturated porous sediments can be established to study the influence of elastic modulus,density,frequency,and load amplitude changes on the model.Based on the Green-Lindsay generalized thermoelasticity theory and Darcy’s law,the thermo-hydro-mechanical coupled dynamic response model and governing equations of heterogeneous deep-sea sediments with nonlinear elastic modulus and density are established.The analytical solutions of dimensionless vertical displacement,vertical stress,excess pore water pressure,and temperature are obtained by means of normal modal analysis,which are depicted graphically.The results show that the changes of elastic modulus and density have few effects on vertical displacement,vertical stress,and temperature,but have great effects on excess pore water pressure.When the mining machine vibrates,the heterogeneity of deep-sea sediments has great influence on vertical displacement,vertical stress,and excess pore water pressure,but has few effects on temperature.In addition,the vertical displacement,vertical stress,and excess pore water pressure of heterogeneous deep-sea sediments change more gently.The variation trends of physical quantities for heterogeneous and homogeneous deep-sea sediments with frequency and load amplitude are basically the same.The results can provide theoretical guidance for deep-sea mining engineering construction.展开更多
The problem of fixed-time group consensus for second-order multi-agent systems with disturbances is investigated.For cooperative-competitive network,two different control protocols,fixed-time group consensus and fixed...The problem of fixed-time group consensus for second-order multi-agent systems with disturbances is investigated.For cooperative-competitive network,two different control protocols,fixed-time group consensus and fixed-time eventtriggered group consensus,are designed.It is demonstrated that there is no Zeno behavior under the designed eventtriggered control.Meanwhile,it is proved that for an arbitrary initial state of the system,group consensus within the settling time could be obtained under the proposed control protocols by using matrix analysis and graph theory.Finally,a series of numerical examples are propounded to illustrate the performance of the proposed control protocol.展开更多
Objective:To summarize recent advancements in mini-percutaneous nephrolithotomy(mini-PCNL)in surgical technique,stone removal strategy,lithotripsy,and surgical model from the current literature.Methods:We conducted a ...Objective:To summarize recent advancements in mini-percutaneous nephrolithotomy(mini-PCNL)in surgical technique,stone removal strategy,lithotripsy,and surgical model from the current literature.Methods:We conducted a narrative review of relevant English-language articles up to October 2022 using the PubMed and Web of Science databases.The following keywords were used in the search:“percutaneous nephrolithotomy”,“minimally invasive percutaneous nephrolithotomy”,“mini-PCNL”,“mini-perc”,“mPCNL”,and“miniaturization”.Results:A series of new progress has been made in many aspects of mini-PCNL,such as further reduction of tract sizedneedle perc and further improvement of robotic-assisted PCNLdartificial intelligence-powered robotic devices.Conclusion:Many studies and trials have been conducted to reduce morbidity and increase the safety and effectiveness of mini-PCNL.It is crucial to realize that miniaturization of PCNL requires not only a smaller percutaneous tract size,but also an adjustment strategically in renal access,stone removal,lithotripsy,and surgical model in general.More large-scale prospective research needs to be carried out to further validate and optimize the safety and effectiveness of mini-PCNL.展开更多
Urolithiasis is a common condition that affects 5%-10%of the population globally[1].Once afflicted,urolithiasis tends to be recurrent,with up to 50%in most cases in 5 years since the first stone event[2].Despite the s...Urolithiasis is a common condition that affects 5%-10%of the population globally[1].Once afflicted,urolithiasis tends to be recurrent,with up to 50%in most cases in 5 years since the first stone event[2].Despite the significant progress in understanding the pathogenesis and management of urolithiasis,the condition remains a significant public health concern.The aim of this special issue of the Asian Journal of Urology was to provide an update on the current state of knowledge regarding the pathogenesis,diagnosis,and management of urolithiasis.展开更多
Current colorectal cancer (CRC) treatments exhibit unwanted cytotoxicity against healthy proliferating cells. Hence, these therapeutics demand higher specificity upon drug delivery, a task that may be facilitated by t...Current colorectal cancer (CRC) treatments exhibit unwanted cytotoxicity against healthy proliferating cells. Hence, these therapeutics demand higher specificity upon drug delivery, a task that may be facilitated by the discovery of anticancer agents bearing critical mechanisms of action. Baicalein is a flavonoid with promising anticancer activity, among other pharmacological benefits, and has therefore been of high clinical interest. We tested baicalein in vitro for its effect on several CRC hallmarks, including the suppression of metastasis (the spread of cancer cells from their initial site), the ability to induce apoptosis (cell death), and the inhibition of proliferation (the growth of cells). The suppression of the metastasis of CRC cells was recorded via two studies: the cell migration assay and the in silico docking of baicalein with toll-like receptor 4 (TLR4) and matrix metalloproteinase-9 (MMP-9). Results from the cell migration assay showed that baicalein inhibited metastasis by up to 25.76% (p 0.01) in a concentration-dependent manner. We then reinforced these results by docking baicalein with TLR4 (binding affinity: -8.4 kcal/mol) and docking baicalein with MMP-9 (binding affinity: -7.9 kcal/mol), classifying strong binding affinities as those less than -6.0 kcal/mol. The induction of cell death was measured using a caspase activity assay. Again, a docking study was done to reinforce the findings from the primary in vitro experiment, though this time between baicalein and caspase-3 (binding affinity: -7.1 kcal/mol). Despite mixed observations in concentration dependence, caspase activity, relative to control, reached a maximal increase of 88.6% (p 0.01), and results from the MTT assay demonstrated a survival rate, relative to control, of as low as 59.64%. Considerations for future studies include the testing of baicalein in vivo and on more aberrative CRC cell lines.展开更多
Objective Chinese herbal medicine(CHM)has been commonly used in Distal Symmetric Polyneuropathy(DSPN)treatment with satisfactory clinical effects,but the underlying pharmacological mechanism of CHM on DSPN remains unc...Objective Chinese herbal medicine(CHM)has been commonly used in Distal Symmetric Polyneuropathy(DSPN)treatment with satisfactory clinical effects,but the underlying pharmacological mechanism of CHM on DSPN remains unclear.We aimed to identify frequently used clinically effective CHM and its potential pharmacological mechanisms for DSPN by conducting meta-analysis and network pharmacology analysis.Methods We searched both Chinese and English databases from March 1990 to October 2022.Studies that met the inclusion criteria were selected for meta-analysis.After extracting the relevant data,we performed meta-analysis and frequency analysis.The active compounds and predicted targets of high-frequency herbs and DSPN-related targets were extracted from public databases.Then we conducted network construction,Gene Ontology(GO)enrichment,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis to discover the potential pharmacological mechanisms.Results Sixteen articles were selected for meta-analysis,and nine high-frequency CHMs were identified,including Radix Astragali seu Hedysari,Rhizoma Ligustici,Caulis Spatholobi,Radix Salviae Miltiorrhizae,Radix Paeoniae Alba,Flos Carthami,Radix Notoginseng,Radix Rehmanniae Recens,Rhizoma Corydalis.Fourteen hub targets including STAT3,CTNNB1,MAPK14,SRC,AKT1,TP53,EGFR,JUN,RELA,MAPK1,FOS,CCND1,HSP90AA1,MYC,and ten active compounds including Quercetin,Kaempferol,Luteolin,Apigenin,beta-sitosterol,Stigmasterol,Caffeic Acid,Aeginetic Acid,Vanillin,and Lauric Acid were identified by network analysis.Enrichment analysis showed that the biological process of hub targets included transcriptional regulation,cell proliferation,redox processes,apoptosis processes,ERK1 and ERK2 cascades,hypoxia reactions,MAPK cascades,and inflammatory responses.The main signalling pathways included HIF,TNF,and PI3K-AKT pathways.Conclusion Nine herbs were involved in the clinical therapeutic effect of CHM on DSPN treatment,and they may exert an anti-DSPN effect by regulating cell proliferation,apoptosis,and redox processes.展开更多
随着全球环境问题日益严重以及能源需求的不断增长,人们对高效环境修复与能源转换技术的需求日益增强.以半导体材料为光催化剂,可将可再生的太阳能转化为化学能,有望成为解决人类面临的能源和环境问题的有效途径.其中,开发高效稳定的光...随着全球环境问题日益严重以及能源需求的不断增长,人们对高效环境修复与能源转换技术的需求日益增强.以半导体材料为光催化剂,可将可再生的太阳能转化为化学能,有望成为解决人类面临的能源和环境问题的有效途径.其中,开发高效稳定的光催化剂是该技术得以实际应用的关键.近几十年,研究人员开发出多种半导体材料并应用于光催化研究.其中,具有可见光响应的有机非金属光催化剂石墨相氮化碳(g-C_(3)N_(4))因其稳定的分子结构,较小的禁带宽度(~2.7 e V)以及合适的能带结构而备受关注.然而,与大多数半导体光催化剂相似,由于传统g-C_(3)N_(4)上的光生电子和空穴极易复合,表面催化活性位点较少,可见光响应范围较窄,使得其催化效率不高.基于g-C_(3)N_(4)独特的有机分子结构,通过引入功能化的特定基团以优化g-C_(3)N_(4)的电子能带结构,促进载流子传输,拓展可见光响应范围,是提高其光催化效率的有效途径.已有研究表明,在各种功能化官能团中,具有强电负性的含氧基团对g-C_(3)N_(4)的Melon单元优化是非常有效的.因此,本文通过g-C_(3)N_(4)与氨基磺酸间的简单固相热反应成功合成了磺酸基功能化的g-C_(3)N_(4)纳米片(SACN),并实现了同步增强的相互作用.根据固体强酸特性,氨基磺酸可以在热处理的辅助下对g-C_(3)N_(4)进行酸刻蚀,从而增加其比表面积以及表面催化活性位点.更重要的是,理论计算与实验表征结果表明,磺酸基团的吸电子诱导效应所产生的电荷驱动力可极大改善g-C_(3)N_(4)的电荷转移动力学,有效抑制了它们的再结合.此外,吸电子诱导效应还可促进g-C_(3)N_(4)的局域电子再分布,进而降低g-C_(3)N_(4)的导带电位,增强光诱导电子的还原能力.光催化性能测试结果表明,SACN-400样品(前驱体中氨基磺酸加入量为400 mg)在光催化分解水制备氢气以及光降解传统污染物领域展现出较好的性能,其在入射光波长为420±15 nm时的产氢表观量子效率为11.03%.综上,本文为设计合成具有较高产氢性能以及污染物降解效率的石墨相氮化碳基光催化剂提供了一种简便有效的策略.展开更多
基金Project supported by the National Natural Science Foundation of China(No.61603322)the Research Foundation of Education Bureau of Hunan Province of China(No.16C1542)
文摘Motivated by the study of regularization for sparse problems,we propose a new regularization method for sparse vector recovery.We derive sufficient conditions on the well-posedness of the new regularization,and design an iterative algorithm,namely the iteratively reweighted algorithm(IR-algorithm),for efficiently computing the sparse solutions to the proposed regularization model.The convergence of the IR-algorithm and the setting of the regularization parameters are analyzed at length.Finally,we present numerical examples to illustrate the features of the new regularization and algorithm.
基金supported by the Fundamental Research Funds for the Central Universities of Central South University(Grant 2021zzts1026).
文摘Background:Lung cancer is one of the most lethal cancers worldwide,but studies have shown that the higher the expression of programmed cell death protein 1 ligand 1(PD-L1)in non-small cell lung cancer(NSCLC),the more likely it will benefit from anti-PD-L1 immunotherapy.The purpose of our study was to collect and analyze abundant clinical samples in order to provide evidence for clinicians and patients who might consider anti-PD-L1 immunotherapy while jointly formulating treatment plans.Methods:On the one hand,we obtained cases from The Cancer Genome Atlas(TCGA)database,including 498 lung squamous cell cancer(LUSC)patients and 515 lung adenocarcinoma(LUAD)patients.We studied the lung caner driver gene in LUSC and LUAD.On the other hand,PD-L1 expression was detected in lung cancer tissues of 1,008 NSCLC patients with immunohistochemistry staining(IHC),and we studied the correlation between PD-L1 protein expression and clinicopathological characteristics.Results:PD-L1 expression was higher in LUSC than in LUAD at the mRNA level.In univariate analysis,PD-L1 expression at the protein level was higher in patients who were males,were LUSC,were smokers,had a tumor diameter>3 cm,had poor differentiation,or had stages Ⅲ-Ⅳ disease.In multivariate analysis,PD-L1 expression was higher in patients who were LUSC or in poor differentiation.Conclusion:In term of protein level,PD-L1 expression was higher in NSCLC patients who were LUSC or in poor differentiation.We recommend that PD-L1 IHC detection can be routinely performed in such populations that are likely to benefit most from PD-L1 immunotherapy.
基金Project supported by the National Natural Science Foundation of China(Nos.12072309,61603322)。
文摘Due to the influence of deep-sea environment,deep-sea sediments are usually heterogeneous,and their moduli of elasticity and density change as depth changes.Combined with the characteristics of deep-sea sediments,the thermo-hydro-mechanical coupling dynamic response model of heterogeneous saturated porous sediments can be established to study the influence of elastic modulus,density,frequency,and load amplitude changes on the model.Based on the Green-Lindsay generalized thermoelasticity theory and Darcy’s law,the thermo-hydro-mechanical coupled dynamic response model and governing equations of heterogeneous deep-sea sediments with nonlinear elastic modulus and density are established.The analytical solutions of dimensionless vertical displacement,vertical stress,excess pore water pressure,and temperature are obtained by means of normal modal analysis,which are depicted graphically.The results show that the changes of elastic modulus and density have few effects on vertical displacement,vertical stress,and temperature,but have great effects on excess pore water pressure.When the mining machine vibrates,the heterogeneity of deep-sea sediments has great influence on vertical displacement,vertical stress,and excess pore water pressure,but has few effects on temperature.In addition,the vertical displacement,vertical stress,and excess pore water pressure of heterogeneous deep-sea sediments change more gently.The variation trends of physical quantities for heterogeneous and homogeneous deep-sea sediments with frequency and load amplitude are basically the same.The results can provide theoretical guidance for deep-sea mining engineering construction.
基金Project supported by the Graduate Student Research Innovation Project of Chongqing(Grant No.CYS22482)the National Natural Science Foundation of China(Grant No.61773082)+1 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJZD-K202000601)the Research Program of Chongqing Talent,China(Grant No.cstc2021ycjhbgzxm0044).
文摘The problem of fixed-time group consensus for second-order multi-agent systems with disturbances is investigated.For cooperative-competitive network,two different control protocols,fixed-time group consensus and fixed-time eventtriggered group consensus,are designed.It is demonstrated that there is no Zeno behavior under the designed eventtriggered control.Meanwhile,it is proved that for an arbitrary initial state of the system,group consensus within the settling time could be obtained under the proposed control protocols by using matrix analysis and graph theory.Finally,a series of numerical examples are propounded to illustrate the performance of the proposed control protocol.
文摘Objective:To summarize recent advancements in mini-percutaneous nephrolithotomy(mini-PCNL)in surgical technique,stone removal strategy,lithotripsy,and surgical model from the current literature.Methods:We conducted a narrative review of relevant English-language articles up to October 2022 using the PubMed and Web of Science databases.The following keywords were used in the search:“percutaneous nephrolithotomy”,“minimally invasive percutaneous nephrolithotomy”,“mini-PCNL”,“mini-perc”,“mPCNL”,and“miniaturization”.Results:A series of new progress has been made in many aspects of mini-PCNL,such as further reduction of tract sizedneedle perc and further improvement of robotic-assisted PCNLdartificial intelligence-powered robotic devices.Conclusion:Many studies and trials have been conducted to reduce morbidity and increase the safety and effectiveness of mini-PCNL.It is crucial to realize that miniaturization of PCNL requires not only a smaller percutaneous tract size,but also an adjustment strategically in renal access,stone removal,lithotripsy,and surgical model in general.More large-scale prospective research needs to be carried out to further validate and optimize the safety and effectiveness of mini-PCNL.
文摘Urolithiasis is a common condition that affects 5%-10%of the population globally[1].Once afflicted,urolithiasis tends to be recurrent,with up to 50%in most cases in 5 years since the first stone event[2].Despite the significant progress in understanding the pathogenesis and management of urolithiasis,the condition remains a significant public health concern.The aim of this special issue of the Asian Journal of Urology was to provide an update on the current state of knowledge regarding the pathogenesis,diagnosis,and management of urolithiasis.
文摘Current colorectal cancer (CRC) treatments exhibit unwanted cytotoxicity against healthy proliferating cells. Hence, these therapeutics demand higher specificity upon drug delivery, a task that may be facilitated by the discovery of anticancer agents bearing critical mechanisms of action. Baicalein is a flavonoid with promising anticancer activity, among other pharmacological benefits, and has therefore been of high clinical interest. We tested baicalein in vitro for its effect on several CRC hallmarks, including the suppression of metastasis (the spread of cancer cells from their initial site), the ability to induce apoptosis (cell death), and the inhibition of proliferation (the growth of cells). The suppression of the metastasis of CRC cells was recorded via two studies: the cell migration assay and the in silico docking of baicalein with toll-like receptor 4 (TLR4) and matrix metalloproteinase-9 (MMP-9). Results from the cell migration assay showed that baicalein inhibited metastasis by up to 25.76% (p 0.01) in a concentration-dependent manner. We then reinforced these results by docking baicalein with TLR4 (binding affinity: -8.4 kcal/mol) and docking baicalein with MMP-9 (binding affinity: -7.9 kcal/mol), classifying strong binding affinities as those less than -6.0 kcal/mol. The induction of cell death was measured using a caspase activity assay. Again, a docking study was done to reinforce the findings from the primary in vitro experiment, though this time between baicalein and caspase-3 (binding affinity: -7.1 kcal/mol). Despite mixed observations in concentration dependence, caspase activity, relative to control, reached a maximal increase of 88.6% (p 0.01), and results from the MTT assay demonstrated a survival rate, relative to control, of as low as 59.64%. Considerations for future studies include the testing of baicalein in vivo and on more aberrative CRC cell lines.
文摘Objective Chinese herbal medicine(CHM)has been commonly used in Distal Symmetric Polyneuropathy(DSPN)treatment with satisfactory clinical effects,but the underlying pharmacological mechanism of CHM on DSPN remains unclear.We aimed to identify frequently used clinically effective CHM and its potential pharmacological mechanisms for DSPN by conducting meta-analysis and network pharmacology analysis.Methods We searched both Chinese and English databases from March 1990 to October 2022.Studies that met the inclusion criteria were selected for meta-analysis.After extracting the relevant data,we performed meta-analysis and frequency analysis.The active compounds and predicted targets of high-frequency herbs and DSPN-related targets were extracted from public databases.Then we conducted network construction,Gene Ontology(GO)enrichment,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis to discover the potential pharmacological mechanisms.Results Sixteen articles were selected for meta-analysis,and nine high-frequency CHMs were identified,including Radix Astragali seu Hedysari,Rhizoma Ligustici,Caulis Spatholobi,Radix Salviae Miltiorrhizae,Radix Paeoniae Alba,Flos Carthami,Radix Notoginseng,Radix Rehmanniae Recens,Rhizoma Corydalis.Fourteen hub targets including STAT3,CTNNB1,MAPK14,SRC,AKT1,TP53,EGFR,JUN,RELA,MAPK1,FOS,CCND1,HSP90AA1,MYC,and ten active compounds including Quercetin,Kaempferol,Luteolin,Apigenin,beta-sitosterol,Stigmasterol,Caffeic Acid,Aeginetic Acid,Vanillin,and Lauric Acid were identified by network analysis.Enrichment analysis showed that the biological process of hub targets included transcriptional regulation,cell proliferation,redox processes,apoptosis processes,ERK1 and ERK2 cascades,hypoxia reactions,MAPK cascades,and inflammatory responses.The main signalling pathways included HIF,TNF,and PI3K-AKT pathways.Conclusion Nine herbs were involved in the clinical therapeutic effect of CHM on DSPN treatment,and they may exert an anti-DSPN effect by regulating cell proliferation,apoptosis,and redox processes.
基金Projects(51774342,51404104) supported by the National Natural Science Foundation of ChinaProject(2017A030313219) supported by the Natural Science Foundation of Guangdong Province,China+2 种基金Project(2015JJ3062) supported by Science Foundation for Youths of Hunan Province,ChinaProjects(2017-BEPC-PT-001052,2016-BEPC-PT-000887) supported by Beijing Synchrotron Radiation Facility Public User Program,ChinaProject(2016-SSRF-PT-004969) supported by the Open Funds of Shanghai Synchrotron Radiation Facility,China
文摘随着全球环境问题日益严重以及能源需求的不断增长,人们对高效环境修复与能源转换技术的需求日益增强.以半导体材料为光催化剂,可将可再生的太阳能转化为化学能,有望成为解决人类面临的能源和环境问题的有效途径.其中,开发高效稳定的光催化剂是该技术得以实际应用的关键.近几十年,研究人员开发出多种半导体材料并应用于光催化研究.其中,具有可见光响应的有机非金属光催化剂石墨相氮化碳(g-C_(3)N_(4))因其稳定的分子结构,较小的禁带宽度(~2.7 e V)以及合适的能带结构而备受关注.然而,与大多数半导体光催化剂相似,由于传统g-C_(3)N_(4)上的光生电子和空穴极易复合,表面催化活性位点较少,可见光响应范围较窄,使得其催化效率不高.基于g-C_(3)N_(4)独特的有机分子结构,通过引入功能化的特定基团以优化g-C_(3)N_(4)的电子能带结构,促进载流子传输,拓展可见光响应范围,是提高其光催化效率的有效途径.已有研究表明,在各种功能化官能团中,具有强电负性的含氧基团对g-C_(3)N_(4)的Melon单元优化是非常有效的.因此,本文通过g-C_(3)N_(4)与氨基磺酸间的简单固相热反应成功合成了磺酸基功能化的g-C_(3)N_(4)纳米片(SACN),并实现了同步增强的相互作用.根据固体强酸特性,氨基磺酸可以在热处理的辅助下对g-C_(3)N_(4)进行酸刻蚀,从而增加其比表面积以及表面催化活性位点.更重要的是,理论计算与实验表征结果表明,磺酸基团的吸电子诱导效应所产生的电荷驱动力可极大改善g-C_(3)N_(4)的电荷转移动力学,有效抑制了它们的再结合.此外,吸电子诱导效应还可促进g-C_(3)N_(4)的局域电子再分布,进而降低g-C_(3)N_(4)的导带电位,增强光诱导电子的还原能力.光催化性能测试结果表明,SACN-400样品(前驱体中氨基磺酸加入量为400 mg)在光催化分解水制备氢气以及光降解传统污染物领域展现出较好的性能,其在入射光波长为420±15 nm时的产氢表观量子效率为11.03%.综上,本文为设计合成具有较高产氢性能以及污染物降解效率的石墨相氮化碳基光催化剂提供了一种简便有效的策略.
