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Multi-functional sites catalysts based on post-synthetic modification of metal-organic frameworks 被引量:7
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作者 Dingxuan Ma Baiyan Li Zhan Shi 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第6期827-830,共4页
Metal-organic frameworks(MOFs) are a unique class of porous crystalline materials that have shown promise for a wide range of applications. MOFs have been explored as a new type of heterogeneous catalytic materials,... Metal-organic frameworks(MOFs) are a unique class of porous crystalline materials that have shown promise for a wide range of applications. MOFs have been explored as a new type of heterogeneous catalytic materials, because of their high surface area, uniform and tunable pores, facile functionalization and incorporation of catalytic active sites. The use of multi-functional sites MOF materials as catalysts for synergistic catalysis and tandem reactions has attracted increasing attention. In this review, we aim to introduce the construction of bi-or multi-functional MOF catalysts with cooperative or cascade functions via post-synthetic modification(PSM). 展开更多
关键词 Metal-organic frameworks multi-functional sites CATALYSIS Post-synthetic modification
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Saturated Alcohols Electrocatalytic Oxidations on Ni-Co Bimetal Oxide Featuring Balanced B-and L-Acidic Active Sites
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作者 Junqing Ma Wenshu Luo +9 位作者 Xunlu Wang Xu Yu Jiacheng Jayden Wang Huashuai Hu Hanxiao Du Jianrong Zeng Wei Chen Minghui Yang Jiacheng Wang Xiangzhi Cui 《Nano-Micro Letters》 2026年第2期105-123,共19页
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro... Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts. 展开更多
关键词 Solid-acid electrocatalyst Alcohol oxidation reaction Bronsted acid sites Lewis acid sites C_(1)-C_(6)saturated alcohols
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Multi-functional SiC/Al Composites for Aerospace Applications 被引量:74
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作者 Cui Yan Wang Lifeng Ren Jianyue 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第6期578-584,共7页
Multi-functional Al-matrix composites with high volume fraction (55%-57%) of SiC particles are produced with the new pressureless infiltration fabrication technology. X-ray detection and microscopic observation disp... Multi-functional Al-matrix composites with high volume fraction (55%-57%) of SiC particles are produced with the new pressureless infiltration fabrication technology. X-ray detection and microscopic observation display the composites which are macroscopically homogeneous without porosity. The investigation further reveals that the SiC/Al composites possess low density (2.94 g/cm^3), high elastic modulus (220 GPa), prominent thermal management function as a result of low coefficient of thermal expansion (8 × 10^4 K^-1) and high thermal conductivity (235 W/(m.K)) as well as unique preventability of resonance vibration. By adopting a series of developed techniques, the multi-functional SiC/Al composites have managed to be made into near-net-shape parts. Many kinds of precision components of space-based optomechanical structures and airborne optoelectronic platform have been turned out. Of them, several typical products are being under test in practices. 展开更多
关键词 COMPOsites multi-function INFILTRATION SIC ALUMINUM aerospace applications
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Regulation Active Sites of Porous GaN Crystal Via Mn_(3)O_(4)Nanosheets for Advanced High Temperature Energy Storage 被引量:1
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作者 Songyang Lv Shouzhi Wang +7 位作者 Qirui Zhang Lin Xu Ge Tian Jiaoxian Yu Guodong Wang Lili Li Xiangang Xu Lei Zhang 《Energy & Environmental Materials》 2025年第3期112-121,共10页
Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and in... Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and inadequate energy densities are bottlenecks to its practical application.Herein,the self-supported GaN/Mn_(3)O_(4) integrated electrode is developed for both energy harvesting and storage under the high temperature environment.The experimental and theoretical calculations results reveal that such integrated structures with Mn-N heterointerface bring abundant active sites and reconstruct low-energy barrier channels for efficient charge transferring,reasonably optimizing the ions adsorption ability and strengthening the structural stability.Consequently,the assembled GaN based supercapacitors deliver the power density of 34.0 mW cm^(-2) with capacitance retention of 81.3%after 10000 cycles at 130℃.This work innovatively correlates the centimeter scale GaN single crystal with ideal theoretical capacity Mn_(3)O_(4) and provides an effective avenue for the follow-up energy storage applications of the wide bandgap semiconductor. 展开更多
关键词 active sites density functional theory gallium nitride crystal high temperature SUPERCAPACITORS
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Synergistic sites over the Zn_(x)ZrO catalyst for targeted cleavage of the C-H bonds of ethane in tandem with CO_(2)activation 被引量:1
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作者 Wenjun Qiang Duohua Liao +6 位作者 Maolin Wang Lingzhen Zeng Weiqi Li Xuedong Ma Liang Yang Shuang Li Ding Ma 《Chinese Journal of Catalysis》 2025年第3期272-284,共13页
The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the ... The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the reduction of greenhouse gas CO_(2)emissions could be achieved.However,the targeted breaking of the C-C/C-H bonds of ethane is still a challenge for the designed catalysts.In this paper,ZnO-doped ZrO_(2)bifunctional catalysts(Zn_(x)ZrO)with different Zn/Zr molar ratios were prepared by the deposition-precipitation method,and the functions of various sites for CO_(2)-ODHE reaction were revealed by in situ characterizations and ethane pulse experiment:the medium-strength acidic Zn-O-Zr sites are responsible for the purposefully cracking of ethane C-H bonds to ethylene,while the more oxygen vacancies(OV)created by the introduction of Zn^(2+)are responsible for the efficient activation C=O bonds of CO_(2),thus promoting the RWGS reaction.In addition,the Zn0.2ZrO catalyst demonstrated excellent catalytic performances,with C_(2)H_(6)conversion,C_(2)H_(4)yield,and CO_(2)conversion about 19.1%,10.5%,and 10.6%within 5 h,respectively(600℃,GHSV=3000 mL/(g·h)).Especially,the initial ethylene space-time yield of 355.5μmol/(min·g)was obtained under 6000 mL/(g·h);Finally,the tandem reaction mechanism of ethane dehydrogenation and RWGS was revealed. 展开更多
关键词 Zn-O-Zr site Oxygen vacancies CO_(2) Ethylene space-time yield Tandem reaction
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Active sites and impact of preparation pH on the Cu/ZnO/ZrO_(2) catalysts for methanol production via CO_(2) hydrogenation
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作者 MENG Xinyue SUN Shangcong +1 位作者 CAO Shuo PENG Bo 《燃料化学学报(中英文)》 北大核心 2025年第11期1569-1582,共14页
Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active... Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial. 展开更多
关键词 CO_(2)hydrogenation methanol synthesis active sites KINETICS
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Methods for the formation of M-N_(x)-C active sites on single-atom catalysts and their role in persulfate activation by non-radical paths
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作者 SI Wen-hao SI Jin-xuan +4 位作者 WANG Kang-jun QI Fei CHEN Jia-bin ZENG Ze-quan HUANG Zhang-gen 《新型炭材料(中英文)》 北大核心 2025年第5期993-1015,共23页
In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(... In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(x)-C)has been identified as the key active site in SACs.Although methods for preparing SACs have been extensively reported,a systematic summary of the direct construction of M-N_(x)-C,espe-cially unconventional metal-nitrogen-carbon(UM-N_(x)-C,x≠4),on SACs for PS non-radical activation has still not been reported.The role of the M-N_(x)-C active sites on PS non-radical activation is discussed and methods for the formation of M-N_(x)-C and UM-N_(x)-C active sites in SACs and the effect of catalyst carriers such as carbon nitride(g-C_(3)N_(4)),MOFs,COFs,and other car-bon materials are reviewed.Direct and indirect methods,especially for UM-N_(x)-C active site formation,are also elaborated.Factors affecting the formation of a M-N_(x)-C active site on SACs are also discussed.Prospects for the use of M-N_(x)-C active sites for the non-radical activation of PS by SACs to remove organic contaminants from wastewater are evaluated. 展开更多
关键词 Single-atom catalysts PERSULFATE Non-radical pathway Unconventional metal-nitrogen-carbon active site Organic contaminants
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Assessment of Floristic Diversity at Two Protected Sites on the Outskirts of Sena Oura National Park, Chad
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作者 Robert Tchingonta Maxime Banoin +1 位作者 Koussou Mian-Oudanang Sougnabe Pabame 《Agricultural Sciences》 2025年第1期178-192,共15页
Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highli... Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highlight the floristic diversity of the herbaceous and woody vegetation on these sites in the offing to know the ability of charge into UBT that most support the park peripheral. It took place on two experimental sites on a natural course in two villages: Wazetelan and Massang. The approach used for the study was a survey using the systematic sampling method and a 30 m × 30 m plot. The survey consisted in listing all the taxa in a floristically homogeneous plot, each assigned the Braun-Blanquet dominance abundance coefficient. These surveys revealed a floristic richness of 73 species, 58 genera, including 46 herbaceous and 26 woody species. The Shannon result gives H1' = 0.12 bit for herbaceous species and H2' = 0.44 bit for woody species, meaning that the herbaceous and woody populations of all the surveys have a very low species diversity, as H' < 3 according to the Shannon index assessment threshold. Herbaceous species are divided into 13 families and 33 genera. The most represented families are Fabaceae (27.3%) and Poaceae (21.9%). Most of the other families (1.3%) have only one species, if any. Herbaceous species are divided into 33 genera grouped into 13 families. The most represented families are Fabaces (16 species), 34%, and Poaceae (12 species), 26%. The 26 woody species, most of which come from itinerant surveys, are distributed across 24 genera and 12 families, the most important of which is Fabaceae with 09 species (34.6%). This floristic assessment, in terms of quantity and quality, has enabled us to estimate the carrying capacity of the two pastoral enclaves in Dari and Goumadji cantons, and to guide the government’s actions with regard to rangeland management. 展开更多
关键词 Floristic Diversity Protected sites PERIPHERY Area Producty CHAD
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Prediction of RNA m6A Methylation Sites in Multiple Tissues Based on Dual-branch Residual Network
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作者 GUO Xiao-Tian GAO Wei +2 位作者 CHEN Dan LI Hui-Min TAN Xue-Wen 《生物化学与生物物理进展》 北大核心 2025年第11期2900-2915,共16页
Objective N6-methyladenosine(m6A),the most prevalent epigenetic modification in eukaryotic RNA,plays a pivotal role in regulating cellular differentiation and developmental processes,with its dysregulation implicated ... Objective N6-methyladenosine(m6A),the most prevalent epigenetic modification in eukaryotic RNA,plays a pivotal role in regulating cellular differentiation and developmental processes,with its dysregulation implicated in diverse pathological conditions.Accurate prediction of m6A sites is critical for elucidating their regulatory mechanisms and informing drug development.However,traditional experimental methods are time-consuming and costly.Although various computational approaches have been proposed,challenges remain in feature learning,predictive accuracy,and generalization.Here,we present m6A-PSRA,a dual-branch residual-network-based predictor that fully exploits RNA sequence information to enhance prediction performance and model generalization.Methods m6A-PSRA adopts a parallel dual-branch network architecture to comprehensively extract RNA sequence features via two independent pathways.The first branch applies one-hot encoding to transform the RNA sequence into a numerical matrix while strictly preserving positional information and sequence continuity.This ensures that the biological context conveyed by nucleotide order is retained.A bidirectional long short-term memory network(BiLSTM)then processes the encoded matrix,capturing both forward and backward dependencies between bases to resolve contextual correlations.The second branch employs a k-mer tokenization strategy(k=3),decomposing the sequence into overlapping 3-mer subsequences to capture local sequence patterns.A pre-trained Doc2vec model maps these subsequences into fixeddimensional vectors,reducing feature dimensionality while extracting latent global semantic information via context learning.Both branches integrate residual networks(ResNet)and a self-attention mechanism:ResNet mitigates vanishing gradients through skip connections,preserving feature integrity,while self-attention adaptively assigns weights to focus on sequence regions most relevant to methylation prediction.This synergy enhances both feature learning and generalization capability.Results Across 11 tissues from humans,mice,and rats,m6A-PSRA consistently outperformed existing methods in accuracy(ACC)and area under the curve(AUC),achieving>90%ACC and>95%AUC in every tissue tested,indicating strong cross-species and cross-tissue adaptability.Validation on independent datasets—including three human cell lines(MOLM1,HEK293,A549)and a long-sequence dataset(m6A_IND,1001 nt)—confirmed stable performance across varied biological contexts and sequence lengths.Ablation studies demonstrated that the dual-branch architecture,residual network,and self-attention mechanism each contribute critically to performance,with their combination reducing interference between pathways.Motif analysis revealed an enrichment of m6A sites in guanine(G)and cytosine(C),consistent with known regulatory patterns,supporting the model’s biological plausibility.Conclusion m6A-PSRA effectively captures RNA sequence features,achieving high prediction accuracy and robust generalization across tissues and species,providing an efficient computational tool for m6A methylation site prediction. 展开更多
关键词 N6-methyladenosine site Doc2vec BiLSTM dual-branch residual network self-attention
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Revisiting Active Sites for Nitrogen Reduction Reaction on 2D Materials Supported Metal Atoms: A Theoretical Investigation
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作者 Mingxin Qin Wenhua Zhang 《Chinese Journal of Chemical Physics》 2025年第3期311-322,I0025-I0036,I0109,共25页
Single atom catalysts supported by two-dimensional(2D)materials,including graphene,g-C_(3)N_(4),and graphdiyne,ex-hibit promising electrocatalytic nitrogen reduction reaction(NRR)activity.Nevertheless,sometimes theore... Single atom catalysts supported by two-dimensional(2D)materials,including graphene,g-C_(3)N_(4),and graphdiyne,ex-hibit promising electrocatalytic nitrogen reduction reaction(NRR)activity.Nevertheless,sometimes theoretical works failed to predict the high activity of NRR of single atom cat-alysts,especially for Fe,Co,Mn,Cu,Ru.In this work,based on DFT calculations,it is suggested that dual-atom sites on N doped graphene(M_(2)@N-graphene)rather than single-atom sites are more likely to be the active sites for NRR.Notably,Fe_(2)@N_(3),Co_(2)@N_(2),Mn_(2)@N_(2),Cu_(2)@N_(1),and Ru_(2)@N_(3)endow the best catalytic activity with corresponding limiting potentials of-0.26,-0.18,-0.17,-0.39,and-0.30 V,re-spectively.Furthermore,on g-C_(3)N_(4)and graphdiyne,triple-atom sites(TAS,M_(3))such as Ru_(3)(Co_(3))@g-C_(3)N_(4)and Ru_(3)(Rh_(3))@graphdiyne are expected to exhibit higher stability and NRR catalytic performance than single-atom sites(SAS)and dual-atom sites(DAS),with corresponding limiting potentials of-0.28,-0.48,-0.24,and-0.23 V.The calculated results with the corresponding experimental potentials indicate that the origin of superior NRR ac-tivity observed in experiments may be contributed by M_(2)or M_(3)on 2D materials.This study provides an in-depth investigation into real active NRR sites of metal atoms supported on 2D materials and contributes to the design of effective NRR catalysts. 展开更多
关键词 Single-atom catalysts Dual-atom sites Density functional theory Electrocat-alytic nitrogen reduction Active sites
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Exploration of multi-functional peptides with bioactive and flavorful properties in Inner Mongolian cheese by peptidomics and bioinformatics
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作者 Yuqian Zheng Zhiyong Cui +8 位作者 Shengnan Wang Chengliang Qi Amin Zhang Xueqian Guo Shilong Zhao Yuan Liu Zhihai Gao Xinya Ma Wenli Wang 《Food Science and Human Wellness》 2025年第9期3461-3471,共11页
The naturally fermented Inner Mongolian cheese’s flavor and nutritional value make it a popular choice among customers.In this work,to create multi-functional peptides that have taste and biological activity,peptidom... The naturally fermented Inner Mongolian cheese’s flavor and nutritional value make it a popular choice among customers.In this work,to create multi-functional peptides that have taste and biological activity,peptidomics and bioinformatics were used to screen flavor peptides from Inner Mongolian cheese and further assess their antioxidant and angiotensin I-converting enzyme(ACE)inhibitory properties.According to sensory data,YH8 and IL7 had detectable bitter tastes with low thresholds of 0.03 and 0.06 mmol/L,respectively.With an umami threshold range of 0.24‒0.81 mmol/L,VQ6,FK13,HP13 and QT14 exhibited a range of flavors dominated by umami,including sweet,bitter,salty,sour and kokumi.Antioxidant activity wise,YH8,VQ6,HP13 and QT14 were well represented.The above-mentioned peptides all had some ACE inhibitory effect.The bitter peptide IL7(IC_(50)=0.08 mmol/L)had the highest level of ACE inhibitory activity,followed by YH8(IC_(50)=0.33 mmol/L).These multi-functional peptides,which have been assessed for bioactive and taste features in Inner Mongolian cheese,may have positive impacts on health and harmonize the cheese’s overall flavor.These results suggest that some flavor peptides produced in fermented foods might be with bioactivities while providing a basis for the exploration and application of multi-functional peptides. 展开更多
关键词 Inner Mongolian cheese multi-functional peptides Flavor peptides ANTIOXIDANTS ACE inhibitory Molecular docking
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Corrigendum to“Multi-functional photonic spin Hall effect sensor controlled by phase transition”
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作者 Jie Cheng Rui-Zhao Li +3 位作者 Cheng Cheng Ya-Lin Zhang Sheng-Li Liu Peng Dong 《Chinese Physics B》 2025年第9期671-671,共1页
Figure 6(a)in the paper[Chin.Phys.B 33074203(2024)]was incorrect due to editorial oversight.The correct figure is provided.This modification does not affect the result presented in the paper.
关键词 CORRIGENDUM photonic spin Hall effect multi-functional sensors phase transition sensing performance
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Functional macrocyclic arenes with active binding sites inside cavity for biomimetic molecular recognition
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作者 Xixian Sun Shengke Li +1 位作者 Ruibing Wang Leyong Wang 《Chinese Chemical Letters》 2025年第4期1-2,共2页
Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active... Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active sites inside the cavity of macrocyclic arenes to better mimic molecular recognition of bioreceptors and enzymes.The editorial aims to enlighten scientists in this field when they develop novel macrocycles for molecular recognition, supramolecular assembly, and applications. 展开更多
关键词 supramolecular assembly orthogonal interactions introducing active sites active binding sites macrocyclic arenes molecular recognition orthogonal interactions small molecules biomimetic molecular recognition
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Integrated single-cell transcriptomic map of pig kidney cells across various periods and anatomical sites
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作者 Tian-Xiong Yao Na Li Lu-Sheng Huang 《Zoological Research》 2025年第2期469-482,共14页
The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across ... The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across different physiological states.In this study,single-cell RNA sequencing was used to profile 138469 cells from 12 pig kidney samples collected during the embryonic(E),fattening(F),and pregnancy(P)periods,identifying 29 cell types.Proximal tubule(PT)cells exhibited elevated expression of metabolism-related transcription factors(TFs),including GPD1,ACAA1,and AGMAT,with validation across multiple individuals,periods,and species.Fluorescence homologous double-labeling of paraffin sections further confirmed the expression of ACAA1 and AGMAT in PT cells.Comparative analysis of pig and human kidneys revealed a high degree of similarity among corresponding cell types.Analysis of cell-type heterogeneity highlighted the diversity of thick ascending limb(TAL)cells,identifying a TAL subpopulation related to immune function.Additionally,the functional heterogeneity of kidney-resident macrophages(KRM)was explored across different anatomical sites.In the renal medulla,KRM were implicated in phagocytosis and leukocyte activation,whereas in the renal pelvis,they functioned as ligands,recruiting neutrophils with bactericidal activity to the renal pelvis to combat urinary tract infections. 展开更多
关键词 PIG Kidney Single-cell RNA sequencing PERIODS Anatomical sites
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Deciphering Local Microstrain‑Induced Optimization of Asymmetric Fe Single Atomic Sites for Efficient Oxygen Reduction
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作者 Peng Zhang Siying Huang +5 位作者 Kuo Chen Xiaoqi Liu Yachao Xu Yongming Chai Yunqi Liu Yuan Pan 《Nano-Micro Letters》 2025年第11期395-409,共15页
Disrupting the symmetric electron distribution of porphyrin-like Fe singleatom catalysts has been considered as an effective way to harvest high intrinsic activity.Understanding the catalytic performance governed by g... Disrupting the symmetric electron distribution of porphyrin-like Fe singleatom catalysts has been considered as an effective way to harvest high intrinsic activity.Understanding the catalytic performance governed by geometric microstrains is highly desirable for further optimization of such efficient sites.Here,we decipher the crucial role of local microstrain in boosting intrinsic activity and durability of asymmetric Fe single-atom catalysts(Fe-N_(3)S_(1))by replacing one N atom with S atom.The high-curvature hollow carbon nanosphere substrate introduces 1.3%local compressive strain to Fe-N bonds and 1.5%tensile strain to Fe-S bonds,downshifting the d-band center and accelerating the kinetics of*OH reduction.Consequently,highly curved Fe-N_(3)S_(1)sites anchored on hollow carbon nanosphere(FeNS-HNS-20)exhibit negligible current loss,a high half-wave potential of 0.922 V vs.RHE and turnover frequency of 6.2 e^(−1)s^(−1)site−1,which are 53 mV more positive and 1.7 times that of flat Fe-N-S counterpart,respectively.More importantly,multiple operando spectroscopies monitored the dynamic optimization of strained Fe-N_(3)S_(1)sites into Fe-N_(3)sites,further mitigating the overadsorption of*OH intermediates.This work not only sheds new light on local microstrain-induced catalytic enhancement,but also provides a plausible direction for optimizing efficient asymmetric sites via geometric configurations. 展开更多
关键词 Local microstrain Asymmetric sites Dynamic mechanism Single-atom catalysts Oxygen reduction
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Research on Optimization Algorithm for Video Recognition Accuracy in Smart Construction Sites
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作者 Xiang Gao Lei Nie +1 位作者 Yinan Wang Chi Zhang 《Journal of Electronic Research and Application》 2025年第6期54-58,共5页
Aiming at the problems faced by construction site video management in the recognition of cigarette butts,reflective vests,and other objects,such as small target confusion,high-brightness false alarms,occlusion missed ... Aiming at the problems faced by construction site video management in the recognition of cigarette butts,reflective vests,and other objects,such as small target confusion,high-brightness false alarms,occlusion missed detections,and poor adaptability to complex environments,this study proposes a recognition accuracy optimization algorithm based on multimodal fusion.The research constructs a dataset containing three modalities of data:visible light,infrared,and millimeter-wave.The Dust-GAN algorithm is adopted to realize dust removal and enhancement of dusty images,and the SAA module is introduced into YOLOv8-s to improve the small target recall rate.Meanwhile,three-modal feature fusion is achieved,and channel pruning and quantization-aware training are used to realize algorithm lightweighting.The algorithm was deployed and operated on-site for 3 months,effectively reducing the construction site safety accident rate by 65%,which provides a solution for safety management and control in smart construction sites under complex environments. 展开更多
关键词 Smart construction site Multimodal fusion Edge computing YOLOv8 SAA
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Construction of Bronsted sites on pyrite surface via plasma technology for efficient hydrolysis of microcystins-LR
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作者 Qing Zhang Yuting He +3 位作者 Jing Zhang Yadong Li Yanfen Fang Yunzhi Tan 《Journal of Environmental Sciences》 2025年第9期622-632,共11页
Enhancing the catalytic hydrolysis efficiency of microcystins(MCs)at ambient temperature has been a persistent challenge in water treatment.We employed N_(2)/low-temperature plasma technology to modify the surface of ... Enhancing the catalytic hydrolysis efficiency of microcystins(MCs)at ambient temperature has been a persistent challenge in water treatment.We employed N_(2)/low-temperature plasma technology to modify the surface of natural pyrites(NP),and the resulting nitrogenmodified pyrites(NPN)with a nanorod structure and new Fe-Nx sites are more efficient for the hydrolysis of microcystins-LR(MC-LR).Kinetic experiments revealed that NPN exhibited significantly higher hydrolysis activity(k_(obs)=0.1471 h^(-1))than NP(0.0914 h^(-1)).Liquid chromatography-mass spectrometry(LC/MS)for the intermediates produced by hydrolyzing MC-LR,in situ attenuated total reflectance Fourier transform infrared spectroscopy(in situ ATR-FTIR)and X-ray photoelectron spectroscopy(XPS)analysis unfolded that the Fe and N atoms of Fe-Nx sites on the surface act of NPN as Lewis acid and Bronsted basic respectively,selectively breaking amide bond on MC-LR molecule.This study demonstrates the effectiveness of plasma technology in modifying mineral materials to enhance their catalytic activity,providing a new method for eliminating MCs in practical water treatment. 展开更多
关键词 Natural pyrite Plasma technology Brönsted sites Microcystins-LR Hydrolysis mechanism
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Pd_(1)-O-Ti dual sites for efficient electrochemical active hydrogen generation and bromate reduction
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作者 Wei Hou Qian Zheng +11 位作者 Hengyue Xu Guangming Zhan Long Zhao Jie Dai Jiaxian Wang Xingyue Zou Bing Zhou Lufa Hu Ruizhao Wang Kaiyuan Wang Yancai Yao Lizhi Zhang 《Journal of Environmental Sciences》 2025年第8期63-72,共10页
Atomic hydrogen(H∗)plays a crucial role in electrochemical reduction technology towards various environmental and energy applications,but suffers from low utilization efficiency arisen from the undesirable H-H dimeriz... Atomic hydrogen(H∗)plays a crucial role in electrochemical reduction technology towards various environmental and energy applications,but suffers from low utilization efficiency arisen from the undesirable H-H dimerization and the competitive adsorption between water molecule with reactants on the traditional adjacent catalytic sites.Herein,we anchored Pd single atoms on the naturally formed titanium oxide of titanium foam to construct Pd_(1)-O-Ti dual-site electrocatalyst with spatially isolated water dissociation and H∗utilization site,which synchronously inhibits the H-H dimerization and the competitive adsorption of water molecule and targeted reactants.Experiments and theoretical calculations revealed that the Ti-O sites could synergistically dissociate water to H∗,which overflowed to nearby Pd single-atom sites for designed reduction reactions and utilization benefiting from the hydrogen spillover ability of titanium oxide substrate.These Pd_(1)-O-Ti dual sites delivered almost 100%bromate reduction efficiency with a rate constant of 1.57 h^(-1),far superior to those of Pdn-O-Ti with adjacent Pd sites(0.52 h^(-1)),Pd_(1)-N-C with single sites(0.04 h^(-1))and commercial Pd/C(0.18 h^(-1)),respectively.This study sheds light on the importance of integrating synergistic active sites for complicated electrochemical reactions,and provide new insights in improving H∗ utilization for environmental remediation. 展开更多
关键词 Atomic hydrogen Pd single atoms Dual sites Hydrogen spillover Bromate electroreduction
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Quality Risk Management of the Changes of Sponsors and Production Sites of Drug Clinical Trial - Taking FDA’s Management as Reference
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作者 Yu Bing Chen Zhen +1 位作者 Wu Zhiang Yang Jianghong 《Asian Journal of Social Pharmacy》 2025年第2期146-157,共12页
Objective To explore the risk management of the changes of sponsors and/or production sites during drug clinical trials based on the theories of quality management,risk management,and change management.Methods The met... Objective To explore the risk management of the changes of sponsors and/or production sites during drug clinical trials based on the theories of quality management,risk management,and change management.Methods The method of failure modes and effect analysis(FMEA)was used to identify risks through literature research,expert consultation,comparative research,and comprehensive analysis.Besides,risk priority number(RPN)was used to evaluate the risks.Results and Conclusion A FMEA of the changes of sponsors and/or production sites in clinical trials was constructed and RPN values of every failure mode and causes were obtained.Based on the RPN values,the core risk control points for different combination modes of sponsors and/or production sites after their changes were identified.It is recommended that China should strengthen the construction of the sponsor responsibility system.In addition,the changes of sponsors and/or production sites during the clinical trial period should be allowed in an orderly manner under the premise of ensuring the quality of clinical trials and subject protection. 展开更多
关键词 SPONSOR production site quality management risk management change management drug clinical trials
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Molecular-based porous polymers with precise sites for photoreduction of carbon dioxide
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作者 Wei-Jia Wang Kaihong Chen 《Chinese Chemical Letters》 2025年第1期201-213,共13页
Photocatalytic CO_(2)reduction reaction(CO_(2)RR)is one of the promising strategies for sustainably producing solar fuels.The precise identification of catalytic sites and the enhancement of photocatalytic CO_(2)conve... Photocatalytic CO_(2)reduction reaction(CO_(2)RR)is one of the promising strategies for sustainably producing solar fuels.The precise identification of catalytic sites and the enhancement of photocatalytic CO_(2)conversion is imperative yet quite challenging.This critical review summarizes recent advances in porous photo-responsive polymers,including covalent organic frameworks(COFs),covalent triazine frameworks(CTFs),and conjugated microporous polymers(CMPs),those can be rationally designed from the molecular level for visible-light-driven photocatalytic CO_(2)reduction.Additionally,special emphasis is placed on how the well-defined active sites on these polymers can influence their properties and photocatalytic performance.The precise regulation and control of microenvironments and electronic properties of metal active centers are crucial for boosting catalytic efficiency and selectivity,as well as for the design of better photocatalysts for CO_(2)reduction. 展开更多
关键词 Carbon dioxide reduction PHOTOCATALYSIS Porous polymers Well-defined catalytic sites Molecular level
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