Two new Mn(Ⅱ)coordination polymers,namely{[Mn_(2)(HL)(phen)_(3)(H_(2)O)_(2)]·7.5H_(2)O}_n(1)and[Mn_(4)(HL)_(2)(1,4-bib)_(3)(H_(2)O)_(2)]_n(2),were synthesized under hydrothermal conditions by using Mn(Ⅱ)ions an...Two new Mn(Ⅱ)coordination polymers,namely{[Mn_(2)(HL)(phen)_(3)(H_(2)O)_(2)]·7.5H_(2)O}_n(1)and[Mn_(4)(HL)_(2)(1,4-bib)_(3)(H_(2)O)_(2)]_n(2),were synthesized under hydrothermal conditions by using Mn(Ⅱ)ions and 6-(3',4'-dicarboxylphenoxy)-1,2,4-benzenetricarboxylic acid(H_(5)L)in the presence of N-auxiliary ligands 1,10-phenanthroline(phen)and1,4-bis(1H-imidazol-1-yl)benzene(1,4-bib).The structures of coordination polymers 1 and 2 were characterized by infrared spectroscopy,single-crystal X-ray diffraction,thermogravimetric analysis,and powder X-ray diffraction.Single-crystal X-ray diffraction reveals that 1 has a 1D chain structure based on binuclear Mn(Ⅱ)units,while 2 features a(3,8)-connected 3D network structure based on tetranuclear Mn(Ⅱ)units.Magnetic studies show that 1 and 2exhibit antiferromagnetic interactions between manganese ions.2 shows stronger antiferromagnetic interactions due to the shorter Mn…Mn distances within the tetranuclear manganese units.CCDC:2357601,1;2357602,2.展开更多
Two new transition-metal coordination polymers,{[Cd(oba)(L)_(2)]·H_(2)O}_n(1)and[Cd(4-nph)(L)_(2)]_n(2)(H_(2)oba=4,4'-oxydibenzoic acid,4-H_(2)nph=4-nitrophthalic acid,L=2,2'-biimidazole),were successfull...Two new transition-metal coordination polymers,{[Cd(oba)(L)_(2)]·H_(2)O}_n(1)and[Cd(4-nph)(L)_(2)]_n(2)(H_(2)oba=4,4'-oxydibenzoic acid,4-H_(2)nph=4-nitrophthalic acid,L=2,2'-biimidazole),were successfully synthesized under hydrothermal conditions and characterized structurally by IR spectroscopy,elemental analyses,single-crystal X-ray diffraction,powder X-ray diffraction,and thermogravimetric analysis.The results of single-crystal X-ray diffraction show that complex 1 presents a 1D zigzag chain structure and further extends to a 2D network through N—H…O hydrogen bonds andπ-πstacking interactions.Meanwhile,complex 2 has a zero-dimensional structure and also extends to form a 2D network through N—H…O hydrogen bonds andπ-πstacking interactions.In addition,both 1and 2 exhibited luminescent properties in the solid state.Furthermore,quantum chemical calculations were carried out on the"molecular fragments"extracted from the crystal structures of 1 and 2 using the PBE0/LANL2DZ method constructed by the Gaussian 16 program.The calculated values signify a significant covalent interaction between the coordination atoms and the Cd(Ⅱ)ions.CCDC:2332173,1;2332176,2.展开更多
Rare earth elements(REEs) are associated with phosphorite,which is an important strategic reserve resource.During sorting process of phosphorite,REEs may move with specific host minerals,however,occurrence state and m...Rare earth elements(REEs) are associated with phosphorite,which is an important strategic reserve resource.During sorting process of phosphorite,REEs may move with specific host minerals,however,occurrence state and moving pattern of REEs from rock to products are still unclear,which limits separation and enrichment of REEs from phosphorite.Mappings of scanning electron microscope(SEM) and electron probe X-ray micro-analyzer(EPMA) of REEs are highly consistent with those of calcium and phosphorus,and complementary with that of magnesium,which indicates that fluorapatite(Fap) is the main host mineral of REEs.The results of flotation and leaching experiments further indicate that REEs are enriched along with Fap from phosphorite to products.Occupied sites and occupation number of REEs were obtained by X-ray diffraction(XRD) refinement based on the Rietveld method.La,Ce,Nd,and Y can occupy both Ca1 and Ca2 sites.The ratios of La,Ce,Nd,and Y at Ca2 and Cal sites are 4.20,3.70,3.00,and 1.33,showing a decreasing trend,indicating that La,Ce,and Nd tend to occupy Ca2 sites,while Y tends to occupy Ca1 sites.X-ray absorption fine structure(XAFS) shows that REEs mainly form coordinate structures with oxygen and fluorine,which is a direct evidence that REEs replace calcium(Ⅱ) in phosphorite in an isomorphism form.Coordination structure and polyhedral configuration analysis indicate that substitution degree of La,Ce,Nd,and Y is Y> La> Ce≈Nd from easy to difficult at Cal and Ca2 sites.The research enriches the mineralization theory of REEs-bearing phosphorite and provides certain theoretical guidance for selective enrichment of REEs from phosphorite.展开更多
The development of highly efficient non-precious metal-nitrogen-carbon(M-N-C)electrocatalysts is a key scientific issue for improving the performance of metal-air batteries and fuel cells.Due to the symmetric charge d...The development of highly efficient non-precious metal-nitrogen-carbon(M-N-C)electrocatalysts is a key scientific issue for improving the performance of metal-air batteries and fuel cells.Due to the symmetric charge distribution of the traditional M-N_(4)active site,the adsorption energy of the key oxygen intermediates in the process of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is difficult to reach the optimal value,which seriously limits the catalytic efficiency.The core of solving this problem lies in the accurate modulation of the coordination environment of the M-N_(4)site,which can realize the breakthrough improvement of the catalytic performance by synergistically optimizing the geometric configuration and electronic structure.In this paper,we systematically analyze the ORR/OER reaction mechanism and then comprehensively review the four main strategies to optimize the coordination environment of M-N-C:metal site regulation,coordination number engineering,non-metal atom doping,and carbon support regulation.Through an in-depth analysis of the structure-activity relationship between the coordination configuration and catalytic performance,the core challenges faced by current research are pointed out,and future research directions are envisioned.This work aims to provide theoretical references for the directional construction of highly efficient M-N-C catalysts with optimized coordination environments.展开更多
Proton exchange membrane fuel cells have been identified as a potentially valuable technology for the efficient conversion of hydrogen energy into electrical energy.Nevertheless,one significant constraint on the perfo...Proton exchange membrane fuel cells have been identified as a potentially valuable technology for the efficient conversion of hydrogen energy into electrical energy.Nevertheless,one significant constraint on the performance of fuel cells is the oxygen reduction reaction(ORR).It is meaningful to progress the development of representative ORR electrocatalysts.In recent times,there has been an intensified focus on single-atom catalysts(SACs)due to the advantages of homogeneous distribution and high atom utilization efficiency.In particular,the coordination structure of metal sites plays an important role in the electrochemical performance of SACs.However,the relationship between coordination structures and catalytic performance remains unclear.In this review,we summarized the research progress on SACs in electrocatalytic ORR in recent years.Then the structure-activity relationship in the symmetric and asymmetric coordination structures of SACs was clarified.We further proposed rational design principles for regulating the coordination structure of SACs.Finally,the opportunities and challenges were discussed.展开更多
Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four plan...Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four planar N-coordination and one axial P-coordination(Co-N_(4)P_(1))are decorated on the lateral edges of nanorod-like crystalline g-C_(3)N_(4)(CCN)photocatalysts.Significantly,the electronic structures of central Co as active sites for O_(2) reduction reaction(ORR)and planar N-coordinator as active sites for H_(2)O oxidation reaction(WOR)in Co-N_(4)P_(1) can be well regulated by the synergetic effects of introducing axial P-coordinator,in contrast to the decorated Co single-atoms with only four planar N-coordination(Co-N_(4)).Specifically,directional photoelectron accumulation at central Co active sites,induced by an introduced midgap level in Co-N_(4)P_(1),mediates the ORR active sites from 4e–-ORR-selective terminal–NH_(2) sites to 2e–-ORR-selective Co sites,moreover,an elevated d-band center of Co 3d orbital strengthens ORR intermediate*OOH adsorption,thus jointly facilitating a highly selective and active 2e^(–)-ORR pathway to H_(2)O_(2) photosynthesis.Simultaneously,a downshifted p-band center of N_(2)p orbital in Co-N_(4)P_(1) weakens WOR intermediate*OH adsorption,thus enabling a preferable 2e^(–)-WOR pathway toward H_(2)O_(2) photosynthesis.Subsequently,Co-N_(4)P_(1) exhibits exceptional H_(2)O_(2) photosynthesis efficiency,reaching 295.6μmol g^(-1) h^(-1) with a remarkable solar-to-chemical conversion efficiency of 0.32%,which is 15 times that of Co-N_(4)(19.2μmol g^(-1) h^(-1))and 10 times higher than CCN(27.6μmol g^(-1) h^(-1)).This electronic structure modulation on single-atom catalysts offers a promising strategy for boosting the activity and selectivity of H_(2)O_(2) photosynthesis.展开更多
Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and hi...Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.展开更多
Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated...Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated under variable nutrient levels is lacking.Here,biofilm colonization patterns and community structures responding to variable levels of ammonia and sulfate were explored.From field sampling,NH_(4)^(+)-N was proven key factor governing community structure in attached biofilms,verifying the reliability of selecting target nutrient species in batch experiments.Biofilms exhibited significant compositional differences in field sampling and incubation experiments.As the nutrient increased in batch experiments,the growth of biofilms gradually slowed down and uneven distribution was detected.The proportions of proteins and β-d-glucose polysaccharides in biofilms experienced a decrease in response to elevated levels of nutrients.With the increased of nutrients,themass losses of concretes exhibited an increase,reaching a highest value of 2.37%in the presence of 20 mg/L of ammonia.Microbial communities underwent a significant transition in structure and metabolic functions to ammonia gradient.The highest activity of nitrification was observed in biofilms colonized in the presence of 20 mg/L of ammonia.While the communities and their functions remained relativelymore stable responding to sulfate gradient.Our research provides novel insights into the structures of biofilms attached on HCSs and the metabolic functions in the presence of high level of nutrients,which is of significance for the operation and maintenance of hydraulic engineering structures.展开更多
Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration w...Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration when designing biomedical implants. In this research, ordered structures with Schottky heterojunction functional unit (OSSH) were constructed on titanium implant surfaces for bone regeneration regulation. The Schottky heterojunction functional unit is composed of periodically distributed titanium microdomain and titanium oxide microdomain with different carrier densities and surface potentials. The OSSH regulates the M2-type polarization of macrophages to a regenerative immune response by activating the PI3K-AKT-mTOR signal pathway and further promotes osteogenic differentiation of rat bone marrow mesenchymal stem cells. This work provides fundamental insights into the biological effects driven by the Schottky heterojunction functional units that can electrically modulate osteogenesis.展开更多
Ganoderma polysaccharides(GPs),derived from various species of the Ganoderma genus,exhibit diverse bioactivities,including immune modulation,anti-tumor effects,and gut microbiota regulation.These properties position G...Ganoderma polysaccharides(GPs),derived from various species of the Ganoderma genus,exhibit diverse bioactivities,including immune modulation,anti-tumor effects,and gut microbiota regulation.These properties position GPs as dual-purpose agents for medicinal and functional food development.This review comprehensively explores the structural complexity of six key GPs and their specific mechanisms of action,such as TLR signaling in immune modulation,apoptosis pathways in anti-tumor activity,and their prebiotic effects on gut microbiota.Additionally,the structure-activity relationships(SARs)of GPs are highlighted to elucidate their biological efficacy.Advances in green extraction techniques,including ultrasonic-assisted and enzymatic methods,are discussed for their roles in enhancing yield and aligning with sustainable production principles.Furthermore,the review addresses biotechnological innovations in polysaccharide biosynthesis,improving production efficiency and making large-scale production feasible.These insights,combined with ongoing research into their bioactivity,provide a solid foundation for developing health-promoting functional food products that incorporate GPs.Furthermore,future research directions are suggested to optimize biosynthesis pathways and fully harness the health benefits of these polysaccharides.展开更多
Based on the observational data from 60 short-period stations deployed in the Jishishan M6.2 earthquake epicenter and adjacent regions(Gansu Province,2023),this study inverted the near-surface S-wave velocity structur...Based on the observational data from 60 short-period stations deployed in the Jishishan M6.2 earthquake epicenter and adjacent regions(Gansu Province,2023),this study inverted the near-surface S-wave velocity structure through teleseismic receiver function analysis by using the amplitude of direct P-wave.The results reveal that the epicentral area(Liugou Township and surroundings)exhibits markedly low S-wave velocities of 400-600 m/s,with a mean value of(500±50)m/s.In contrast,intermountain basins-Guanting Basin and Dahejia Basin-demonstrate significantly elevated velocities,exceeding the epicentral zone by 100-300 m/s,with values concentrated at 600-900 m/s.Notably,localized areas such as Jintian Village and Caotan Village maintain stable S-wave velocities of(700±30)m/s.The western margin tectonic belt of Jishishan displays distinctive velocity differentiation:A pronounced velocity gradient zone along the 35.8°N latitude boundary separates northern areas(<550 m/s)from southern regions(>750 m/s).These findings demonstrate significant spatial heterogeneity in shallow S-wave velocity structures,primarily controlled by three factors:(1)topographic-geomorphic units,(2)stratigraphic lithological contrasts,and(3)anthropogenic modifications.The persistent low-velocity anomalies(<600 m/s)in the epicentral zone and northern Yellow River T2 terrace likely correlate with Quaternary unconsolidated sediments,enhanced groundwater circulation,and bedrock weathering.These results provide critical geophysical constraints for understanding both the seismogenic environment of the Jishishan earthquake and its damage distribution patterns.Furthermore,they establish a foundational framework for regional seismic intensity evaluation,site amplification analysis,and secondary hazard risk assessment.展开更多
Protein Kinase G(PKG)is an important intracellular signal transduction enzyme,and its activity is modulated by cyclic guanosine monophosphate(cGMP).PKG plays a pivotal role in various significant physiological process...Protein Kinase G(PKG)is an important intracellular signal transduction enzyme,and its activity is modulated by cyclic guanosine monophosphate(cGMP).PKG plays a pivotal role in various significant physiological processes,including vascular smooth muscle relaxation,myocardial cell function regulation,neuron growth,and synaptic plasticity,et al.In recent years,the role of PKG in diseases has gradually attracted attention,and the abnormalities in its signaling pathway are closely related to the occurrence and development of cardiovascular and neurological diseases.Although PKG has been widely studied,its complex functions in different physiological systems and potential innovative applications still need to be further explored.This article reviews the purification techniques for PKG,discusses the advantages and disadvantages of different extraction methods,summarizes the structure and activation mechanism of each domain of PKG,and analyzes the physiological functions of PKG in organisms,especially the well-established roles in the cardiovascular system,nervous system,and endocrine system.The emerging therapeutic applications of PKG are also reviewed.In addition,the challenges of this field are proposed at the end.展开更多
Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmeth...Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2.展开更多
Photocatalytic decomposition of sugars is a promising way of providing H_(2),CO,and HCOOH as sus-tainable energy vectors.However,the production of C_(1) chemicals requires the cleavage of robust C−C bonds in sugars wi...Photocatalytic decomposition of sugars is a promising way of providing H_(2),CO,and HCOOH as sus-tainable energy vectors.However,the production of C_(1) chemicals requires the cleavage of robust C−C bonds in sugars with concurrent production of H_(2),which remains challenging.Here,the photo-catalytic activity for glucose decomposition to HCOOH,CO(C_(1) chemicals),and H_(2) on Cu/TiO_(2)was enhanced by nitrogen doping.Owing to nitrogen doping,atomically dispersed and stable Cu sites resistant to light irradiation are formed on Cu/TiO_(2).The electronic interaction between Cu and nitrogen ions originates valence band structure and defect levels composed of N 2p orbit,distinct from undoped Cu/TiO_(2).Therefore,the lifetime of charge carriers is prolonged,resulting in the pro-duction of C_(1) chemicals and H_(2) with productivities 1.7 and 2.1 folds that of Cu/TiO_(2).This work pro-vides a strategy to design coordinatively stable Cu ions for photocatalytic biomass conversion.展开更多
Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,...Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3.展开更多
Two new Zn~Ⅱ coordination polymers,namely,[Zn L（o-bdc）]n（1） and [Zn L（mbdc）]_n·n H_2O（2）（L = 4？-（3-pyridyl）-3,2？：6？,3？？-terpyridine,H_2（o-bdc） = benzene-1,2-dicarboxylic acid,H_2（m-bdc） = be...Two new Zn~Ⅱ coordination polymers,namely,[Zn L（o-bdc）]n（1） and [Zn L（mbdc）]_n·n H_2O（2）（L = 4？-（3-pyridyl）-3,2？：6？,3？？-terpyridine,H_2（o-bdc） = benzene-1,2-dicarboxylic acid,H_2（m-bdc） = benzene-1,3-dicarboxylic acid）,were synthesized by hydrothermal methods. The crystal structures have been determined by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic C2/c space group,with a = 28.016（2）,b = 11.3815（11）,c = 19.8071（17） ？,β = 133.961（2）°,V = 4546.2（7） ？3,Z = 8,Mr = 539.83,Dc = 1.577 Mg/m^3,μ = 1.127 mm-1,F（000） = 2208,the final R = 0.0426 and w R = 0.0986 for 2875 observed reflections with I 〉 2σ（I） and displays a 1D coordination chain. While compound 2 crystallizes in monoclinic C2/c space group,with a = 15.6003（14）,b = 11.9152（11）,c = 26.633（3） ？,β = 94.320（2）°,V = 4936.5（8） ？~3,Z = 4,M_r = 1115.67,Dc = 1.496 Mg/m^3,μ = 1.043 mm^（-1）,F（000） = 2272,the final R = 0.0499 and w R = 0.1342 for 2659 observed reflections with I 〉 2σ（I） and shows a classical 3D cds topological network with point symbol of {65.8}. Furthermore,thermal stability and luminescent properties of 1 and 2 have also been investigated.展开更多
One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,p...One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,powder X-ray diffraction,X-ray diffraction,and elemental analysis.Complex 1 displays a 1D chain structure,and belongs to P1 group.The solid-state luminescent spectrum of 1 showed an emission band with the maximum at 508 nm(λex=408 nm).It exhibited the emission characteristic of the H_(4)dhtp ligand.The fluorescence of 1 in water displayed the stron-gest intensity.In detecting various metal ions,adding Zr^(4+)led to a blue shift in fluorescence,accompanied by an increase in intensity,whereas the presence of Fe^(3+)resulted in a decrease in luminescence.The changes observed in the IR spectrum indicate an interaction between Fe^(3+)/Zr^(4+)and complex 1,resulting in the variation of luminescence properties.展开更多
3D printing techniques offer an effective method in fabricating complex radially multi-material structures.However,it is challenging for complex and delicate radially multi-material model geometries without supporting...3D printing techniques offer an effective method in fabricating complex radially multi-material structures.However,it is challenging for complex and delicate radially multi-material model geometries without supporting structures,such as tissue vessels and tubular graft,among others.In this work,we tackle these challenges by developing a polar digital light processing technique which uses a rod as the printing platform.The 3D model fabrication is accomplished through line projection.The rotation and translation of the rod are synchronized to project and illuminate the photosensitive material volume.By controlling the distance between the rod and the printing window,we achieved the printing of tubular structures with a minimum wall thickness as thin as 50 micrometers.By controlling the width of fine slits at the printing window,we achieved the printing of structures with a minimum feature size of 10 micrometers.Our process accomplished the fabrication of thin-walled tubular graft structure with a thickness of only 100 micrometers and lengths of several centimeters within a timeframe of just 100 s.Additionally,it enables the printing of axial multi-material structures,thereby achieving adjustable mechanical strength.This method is conducive to rapid customization of tubular grafts and the manufacturing of tubular components in fields such as dentistry,aerospace,and more.展开更多
A low-cost 1D cobalt-based coordination polymer(CP)[Co(BGPD)(DMSO)_(2)(H_(2)O)_(2)](Co-BD;H2BGPD=N,N'-bis(glycinyl)pyromellitic diimide;DMSO=dimethyl sulfoxide)was synthesized by a simple method,and its crystal st...A low-cost 1D cobalt-based coordination polymer(CP)[Co(BGPD)(DMSO)_(2)(H_(2)O)_(2)](Co-BD;H2BGPD=N,N'-bis(glycinyl)pyromellitic diimide;DMSO=dimethyl sulfoxide)was synthesized by a simple method,and its crystal structure was characterized.In a three-electrode system,Co-BD,as the electrode material for supercapacitors,achieved a specific capacitance of 830 F·g^(-1)at 1 A·g^(-1),equivalent to a specific capacity of 116.4 mAh·g^(-1),and exhibited high-rate capability,reaching 212 F·g^(-1)at 20 A·g^(-1).Impressively,Co-BD||rGO(reduced graphene oxide),representing an asymmetrical supercapacitor,owns a higher energy density of 14.2 Wh·kg^(-1)at 0.80 kW·kg^(-1),and an excellent cycle performance(After 4000 cycles at 1 A·g^(-1),the capacitance retention was up to 94%).CCDC:2418872.展开更多
Titanium and its alloys have been widely applied in many biomedical fields because of its excellent mechanical properties,corrosion resistance and good biocompatibility.However,problems such as rejection,shedding and ...Titanium and its alloys have been widely applied in many biomedical fields because of its excellent mechanical properties,corrosion resistance and good biocompatibility.However,problems such as rejection,shedding and infection will occur after titanium alloy implantation due to the low biological activity of titanium alloy surface.The structures with specific functions,which can enhance osseointegration and antibacterial properties,are fabricated on the surface of titanium implants to improve the biological activity between the titanium implants and human tissues.This paper presents a comprehensive review of recent developments and applications of surface functional structure in titanium and titanium alloy implants.The applications of surface functional structure on different titanium and titanium alloy implants are introduced,and their manufacturing technologies are summarized and compared.Furthermore,the fabrication of various surface functional structures used for titanium and titanium alloy implants is reviewed and analyzed in detail.Finally,the challenges affecting the development of surface functional structures applied in titanium and titanium alloy implants are outlined,and recommendations for future research are presented.展开更多
文摘Two new Mn(Ⅱ)coordination polymers,namely{[Mn_(2)(HL)(phen)_(3)(H_(2)O)_(2)]·7.5H_(2)O}_n(1)and[Mn_(4)(HL)_(2)(1,4-bib)_(3)(H_(2)O)_(2)]_n(2),were synthesized under hydrothermal conditions by using Mn(Ⅱ)ions and 6-(3',4'-dicarboxylphenoxy)-1,2,4-benzenetricarboxylic acid(H_(5)L)in the presence of N-auxiliary ligands 1,10-phenanthroline(phen)and1,4-bis(1H-imidazol-1-yl)benzene(1,4-bib).The structures of coordination polymers 1 and 2 were characterized by infrared spectroscopy,single-crystal X-ray diffraction,thermogravimetric analysis,and powder X-ray diffraction.Single-crystal X-ray diffraction reveals that 1 has a 1D chain structure based on binuclear Mn(Ⅱ)units,while 2 features a(3,8)-connected 3D network structure based on tetranuclear Mn(Ⅱ)units.Magnetic studies show that 1 and 2exhibit antiferromagnetic interactions between manganese ions.2 shows stronger antiferromagnetic interactions due to the shorter Mn…Mn distances within the tetranuclear manganese units.CCDC:2357601,1;2357602,2.
文摘Two new transition-metal coordination polymers,{[Cd(oba)(L)_(2)]·H_(2)O}_n(1)and[Cd(4-nph)(L)_(2)]_n(2)(H_(2)oba=4,4'-oxydibenzoic acid,4-H_(2)nph=4-nitrophthalic acid,L=2,2'-biimidazole),were successfully synthesized under hydrothermal conditions and characterized structurally by IR spectroscopy,elemental analyses,single-crystal X-ray diffraction,powder X-ray diffraction,and thermogravimetric analysis.The results of single-crystal X-ray diffraction show that complex 1 presents a 1D zigzag chain structure and further extends to a 2D network through N—H…O hydrogen bonds andπ-πstacking interactions.Meanwhile,complex 2 has a zero-dimensional structure and also extends to form a 2D network through N—H…O hydrogen bonds andπ-πstacking interactions.In addition,both 1and 2 exhibited luminescent properties in the solid state.Furthermore,quantum chemical calculations were carried out on the"molecular fragments"extracted from the crystal structures of 1 and 2 using the PBE0/LANL2DZ method constructed by the Gaussian 16 program.The calculated values signify a significant covalent interaction between the coordination atoms and the Cd(Ⅱ)ions.CCDC:2332173,1;2332176,2.
基金Project supported by Guizhou Provincial Basic Research Program (Natural Science)(Qian Ke He Basic-ZK 2024 General 626)National Natural Science Foundation of China (52164018)Scientific Research Foundation for High-level Talents of Anhui University of Science and Technology (13210025)。
文摘Rare earth elements(REEs) are associated with phosphorite,which is an important strategic reserve resource.During sorting process of phosphorite,REEs may move with specific host minerals,however,occurrence state and moving pattern of REEs from rock to products are still unclear,which limits separation and enrichment of REEs from phosphorite.Mappings of scanning electron microscope(SEM) and electron probe X-ray micro-analyzer(EPMA) of REEs are highly consistent with those of calcium and phosphorus,and complementary with that of magnesium,which indicates that fluorapatite(Fap) is the main host mineral of REEs.The results of flotation and leaching experiments further indicate that REEs are enriched along with Fap from phosphorite to products.Occupied sites and occupation number of REEs were obtained by X-ray diffraction(XRD) refinement based on the Rietveld method.La,Ce,Nd,and Y can occupy both Ca1 and Ca2 sites.The ratios of La,Ce,Nd,and Y at Ca2 and Cal sites are 4.20,3.70,3.00,and 1.33,showing a decreasing trend,indicating that La,Ce,and Nd tend to occupy Ca2 sites,while Y tends to occupy Ca1 sites.X-ray absorption fine structure(XAFS) shows that REEs mainly form coordinate structures with oxygen and fluorine,which is a direct evidence that REEs replace calcium(Ⅱ) in phosphorite in an isomorphism form.Coordination structure and polyhedral configuration analysis indicate that substitution degree of La,Ce,Nd,and Y is Y> La> Ce≈Nd from easy to difficult at Cal and Ca2 sites.The research enriches the mineralization theory of REEs-bearing phosphorite and provides certain theoretical guidance for selective enrichment of REEs from phosphorite.
基金supported by the Natural Science Foundation of Hebei Province(no.E2024501010)the National Natural Science Foundation of China(no.52374301)+1 种基金the Shijiazhuang Basic Research Project(no.241790667A)the Performance Subsidy Fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(no.22567627H)。
文摘The development of highly efficient non-precious metal-nitrogen-carbon(M-N-C)electrocatalysts is a key scientific issue for improving the performance of metal-air batteries and fuel cells.Due to the symmetric charge distribution of the traditional M-N_(4)active site,the adsorption energy of the key oxygen intermediates in the process of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is difficult to reach the optimal value,which seriously limits the catalytic efficiency.The core of solving this problem lies in the accurate modulation of the coordination environment of the M-N_(4)site,which can realize the breakthrough improvement of the catalytic performance by synergistically optimizing the geometric configuration and electronic structure.In this paper,we systematically analyze the ORR/OER reaction mechanism and then comprehensively review the four main strategies to optimize the coordination environment of M-N-C:metal site regulation,coordination number engineering,non-metal atom doping,and carbon support regulation.Through an in-depth analysis of the structure-activity relationship between the coordination configuration and catalytic performance,the core challenges faced by current research are pointed out,and future research directions are envisioned.This work aims to provide theoretical references for the directional construction of highly efficient M-N-C catalysts with optimized coordination environments.
基金supported the National Natural Science Foundation of China(Nos.22108306 and 22478432)Taishan Scholars Program of Shandong Province(No.tsqn201909065)the Natural Science Foundation of Shandong Province(Nos.ZR2024JQ004 and ZR2021YQ15).
文摘Proton exchange membrane fuel cells have been identified as a potentially valuable technology for the efficient conversion of hydrogen energy into electrical energy.Nevertheless,one significant constraint on the performance of fuel cells is the oxygen reduction reaction(ORR).It is meaningful to progress the development of representative ORR electrocatalysts.In recent times,there has been an intensified focus on single-atom catalysts(SACs)due to the advantages of homogeneous distribution and high atom utilization efficiency.In particular,the coordination structure of metal sites plays an important role in the electrochemical performance of SACs.However,the relationship between coordination structures and catalytic performance remains unclear.In this review,we summarized the research progress on SACs in electrocatalytic ORR in recent years.Then the structure-activity relationship in the symmetric and asymmetric coordination structures of SACs was clarified.We further proposed rational design principles for regulating the coordination structure of SACs.Finally,the opportunities and challenges were discussed.
文摘Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four planar N-coordination and one axial P-coordination(Co-N_(4)P_(1))are decorated on the lateral edges of nanorod-like crystalline g-C_(3)N_(4)(CCN)photocatalysts.Significantly,the electronic structures of central Co as active sites for O_(2) reduction reaction(ORR)and planar N-coordinator as active sites for H_(2)O oxidation reaction(WOR)in Co-N_(4)P_(1) can be well regulated by the synergetic effects of introducing axial P-coordinator,in contrast to the decorated Co single-atoms with only four planar N-coordination(Co-N_(4)).Specifically,directional photoelectron accumulation at central Co active sites,induced by an introduced midgap level in Co-N_(4)P_(1),mediates the ORR active sites from 4e–-ORR-selective terminal–NH_(2) sites to 2e–-ORR-selective Co sites,moreover,an elevated d-band center of Co 3d orbital strengthens ORR intermediate*OOH adsorption,thus jointly facilitating a highly selective and active 2e^(–)-ORR pathway to H_(2)O_(2) photosynthesis.Simultaneously,a downshifted p-band center of N_(2)p orbital in Co-N_(4)P_(1) weakens WOR intermediate*OH adsorption,thus enabling a preferable 2e^(–)-WOR pathway toward H_(2)O_(2) photosynthesis.Subsequently,Co-N_(4)P_(1) exhibits exceptional H_(2)O_(2) photosynthesis efficiency,reaching 295.6μmol g^(-1) h^(-1) with a remarkable solar-to-chemical conversion efficiency of 0.32%,which is 15 times that of Co-N_(4)(19.2μmol g^(-1) h^(-1))and 10 times higher than CCN(27.6μmol g^(-1) h^(-1)).This electronic structure modulation on single-atom catalysts offers a promising strategy for boosting the activity and selectivity of H_(2)O_(2) photosynthesis.
基金supported by the Innovative Research Group Project of the National Natural Science Foundation of China(T2121004)Key Programme(52235007)National Outstanding Youth Foundation of China(52325504).
文摘Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.
基金supported by the National Key Research and Development Project of China(No.2021YFB2600200)the National Natural Science Foundation of China(Nos.52470185 and 52170159)the Open Research Fund of National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,the Fund of National Key Laboratory of Water Disaster Prevention and Key Research and Development Program of Jiangsu Province(No.BE2022601).
文摘Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated under variable nutrient levels is lacking.Here,biofilm colonization patterns and community structures responding to variable levels of ammonia and sulfate were explored.From field sampling,NH_(4)^(+)-N was proven key factor governing community structure in attached biofilms,verifying the reliability of selecting target nutrient species in batch experiments.Biofilms exhibited significant compositional differences in field sampling and incubation experiments.As the nutrient increased in batch experiments,the growth of biofilms gradually slowed down and uneven distribution was detected.The proportions of proteins and β-d-glucose polysaccharides in biofilms experienced a decrease in response to elevated levels of nutrients.With the increased of nutrients,themass losses of concretes exhibited an increase,reaching a highest value of 2.37%in the presence of 20 mg/L of ammonia.Microbial communities underwent a significant transition in structure and metabolic functions to ammonia gradient.The highest activity of nitrification was observed in biofilms colonized in the presence of 20 mg/L of ammonia.While the communities and their functions remained relativelymore stable responding to sulfate gradient.Our research provides novel insights into the structures of biofilms attached on HCSs and the metabolic functions in the presence of high level of nutrients,which is of significance for the operation and maintenance of hydraulic engineering structures.
基金supported by the National Natural Science Foundation of China(Nos.52072127,52201297,U21A2055,and U22A20160)the China Postdoctoral Science Foundation(No.2022M711200)the Royal Society(No.IEC/NSFC/191344)(UK).
文摘Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration when designing biomedical implants. In this research, ordered structures with Schottky heterojunction functional unit (OSSH) were constructed on titanium implant surfaces for bone regeneration regulation. The Schottky heterojunction functional unit is composed of periodically distributed titanium microdomain and titanium oxide microdomain with different carrier densities and surface potentials. The OSSH regulates the M2-type polarization of macrophages to a regenerative immune response by activating the PI3K-AKT-mTOR signal pathway and further promotes osteogenic differentiation of rat bone marrow mesenchymal stem cells. This work provides fundamental insights into the biological effects driven by the Schottky heterojunction functional units that can electrically modulate osteogenesis.
基金supported by the National Natural Science Foundation of China(Nos.82373762,31872675)Major Special Programe of science and technology of Yunnan(202402AA310032,202305AH340005)+1 种基金the Cooperation Project with DR PLANT Company(2023)the Foundation of the State Key Laboratory of Phytochemistry and Plant Resources in West China(Nos.P2020-KF02,P2022-KF10).
文摘Ganoderma polysaccharides(GPs),derived from various species of the Ganoderma genus,exhibit diverse bioactivities,including immune modulation,anti-tumor effects,and gut microbiota regulation.These properties position GPs as dual-purpose agents for medicinal and functional food development.This review comprehensively explores the structural complexity of six key GPs and their specific mechanisms of action,such as TLR signaling in immune modulation,apoptosis pathways in anti-tumor activity,and their prebiotic effects on gut microbiota.Additionally,the structure-activity relationships(SARs)of GPs are highlighted to elucidate their biological efficacy.Advances in green extraction techniques,including ultrasonic-assisted and enzymatic methods,are discussed for their roles in enhancing yield and aligning with sustainable production principles.Furthermore,the review addresses biotechnological innovations in polysaccharide biosynthesis,improving production efficiency and making large-scale production feasible.These insights,combined with ongoing research into their bioactivity,provide a solid foundation for developing health-promoting functional food products that incorporate GPs.Furthermore,future research directions are suggested to optimize biosynthesis pathways and fully harness the health benefits of these polysaccharides.
基金project is supported in part by Broadband Seismic 3D Array Detection(PhaseⅠ),Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project(Grant No.2024ZD1000300)National Natural Science Foundation of China(42204061)Gansu Jishishan 6.2 magnitude earthquake scientific investigation(DQJB23Y45)program。
文摘Based on the observational data from 60 short-period stations deployed in the Jishishan M6.2 earthquake epicenter and adjacent regions(Gansu Province,2023),this study inverted the near-surface S-wave velocity structure through teleseismic receiver function analysis by using the amplitude of direct P-wave.The results reveal that the epicentral area(Liugou Township and surroundings)exhibits markedly low S-wave velocities of 400-600 m/s,with a mean value of(500±50)m/s.In contrast,intermountain basins-Guanting Basin and Dahejia Basin-demonstrate significantly elevated velocities,exceeding the epicentral zone by 100-300 m/s,with values concentrated at 600-900 m/s.Notably,localized areas such as Jintian Village and Caotan Village maintain stable S-wave velocities of(700±30)m/s.The western margin tectonic belt of Jishishan displays distinctive velocity differentiation:A pronounced velocity gradient zone along the 35.8°N latitude boundary separates northern areas(<550 m/s)from southern regions(>750 m/s).These findings demonstrate significant spatial heterogeneity in shallow S-wave velocity structures,primarily controlled by three factors:(1)topographic-geomorphic units,(2)stratigraphic lithological contrasts,and(3)anthropogenic modifications.The persistent low-velocity anomalies(<600 m/s)in the epicentral zone and northern Yellow River T2 terrace likely correlate with Quaternary unconsolidated sediments,enhanced groundwater circulation,and bedrock weathering.These results provide critical geophysical constraints for understanding both the seismogenic environment of the Jishishan earthquake and its damage distribution patterns.Furthermore,they establish a foundational framework for regional seismic intensity evaluation,site amplification analysis,and secondary hazard risk assessment.
基金supported by the National Natural Science Foundation of China(Nos.22374033,22174031,22407037)the Natural Science Foundation of Heilongjiang Province(No.ZD2022B001).
文摘Protein Kinase G(PKG)is an important intracellular signal transduction enzyme,and its activity is modulated by cyclic guanosine monophosphate(cGMP).PKG plays a pivotal role in various significant physiological processes,including vascular smooth muscle relaxation,myocardial cell function regulation,neuron growth,and synaptic plasticity,et al.In recent years,the role of PKG in diseases has gradually attracted attention,and the abnormalities in its signaling pathway are closely related to the occurrence and development of cardiovascular and neurological diseases.Although PKG has been widely studied,its complex functions in different physiological systems and potential innovative applications still need to be further explored.This article reviews the purification techniques for PKG,discusses the advantages and disadvantages of different extraction methods,summarizes the structure and activation mechanism of each domain of PKG,and analyzes the physiological functions of PKG in organisms,especially the well-established roles in the cardiovascular system,nervous system,and endocrine system.The emerging therapeutic applications of PKG are also reviewed.In addition,the challenges of this field are proposed at the end.
文摘Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2.
文摘Photocatalytic decomposition of sugars is a promising way of providing H_(2),CO,and HCOOH as sus-tainable energy vectors.However,the production of C_(1) chemicals requires the cleavage of robust C−C bonds in sugars with concurrent production of H_(2),which remains challenging.Here,the photo-catalytic activity for glucose decomposition to HCOOH,CO(C_(1) chemicals),and H_(2) on Cu/TiO_(2)was enhanced by nitrogen doping.Owing to nitrogen doping,atomically dispersed and stable Cu sites resistant to light irradiation are formed on Cu/TiO_(2).The electronic interaction between Cu and nitrogen ions originates valence band structure and defect levels composed of N 2p orbit,distinct from undoped Cu/TiO_(2).Therefore,the lifetime of charge carriers is prolonged,resulting in the pro-duction of C_(1) chemicals and H_(2) with productivities 1.7 and 2.1 folds that of Cu/TiO_(2).This work pro-vides a strategy to design coordinatively stable Cu ions for photocatalytic biomass conversion.
文摘Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3.
基金supported by the National Natural Science Foundation of China(Nos.21173164 and 21473133)
文摘Two new Zn~Ⅱ coordination polymers,namely,[Zn L（o-bdc）]n（1） and [Zn L（mbdc）]_n·n H_2O（2）（L = 4？-（3-pyridyl）-3,2？：6？,3？？-terpyridine,H_2（o-bdc） = benzene-1,2-dicarboxylic acid,H_2（m-bdc） = benzene-1,3-dicarboxylic acid）,were synthesized by hydrothermal methods. The crystal structures have been determined by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic C2/c space group,with a = 28.016（2）,b = 11.3815（11）,c = 19.8071（17） ？,β = 133.961（2）°,V = 4546.2（7） ？3,Z = 8,Mr = 539.83,Dc = 1.577 Mg/m^3,μ = 1.127 mm-1,F（000） = 2208,the final R = 0.0426 and w R = 0.0986 for 2875 observed reflections with I 〉 2σ（I） and displays a 1D coordination chain. While compound 2 crystallizes in monoclinic C2/c space group,with a = 15.6003（14）,b = 11.9152（11）,c = 26.633（3） ？,β = 94.320（2）°,V = 4936.5（8） ？~3,Z = 4,M_r = 1115.67,Dc = 1.496 Mg/m^3,μ = 1.043 mm^（-1）,F（000） = 2272,the final R = 0.0499 and w R = 0.1342 for 2659 observed reflections with I 〉 2σ（I） and shows a classical 3D cds topological network with point symbol of {65.8}. Furthermore,thermal stability and luminescent properties of 1 and 2 have also been investigated.
文摘One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,powder X-ray diffraction,X-ray diffraction,and elemental analysis.Complex 1 displays a 1D chain structure,and belongs to P1 group.The solid-state luminescent spectrum of 1 showed an emission band with the maximum at 508 nm(λex=408 nm).It exhibited the emission characteristic of the H_(4)dhtp ligand.The fluorescence of 1 in water displayed the stron-gest intensity.In detecting various metal ions,adding Zr^(4+)led to a blue shift in fluorescence,accompanied by an increase in intensity,whereas the presence of Fe^(3+)resulted in a decrease in luminescence.The changes observed in the IR spectrum indicate an interaction between Fe^(3+)/Zr^(4+)and complex 1,resulting in the variation of luminescence properties.
基金supported financially by the Fundamental Research Funds for the Central Universities (YWF-22-K-101,YWF-23-L-805 and YWF-23-YG-QB-006)the support from the National Natural Science Foundation of China (12372106)Fundamental Research Funds for the Central Universities
文摘3D printing techniques offer an effective method in fabricating complex radially multi-material structures.However,it is challenging for complex and delicate radially multi-material model geometries without supporting structures,such as tissue vessels and tubular graft,among others.In this work,we tackle these challenges by developing a polar digital light processing technique which uses a rod as the printing platform.The 3D model fabrication is accomplished through line projection.The rotation and translation of the rod are synchronized to project and illuminate the photosensitive material volume.By controlling the distance between the rod and the printing window,we achieved the printing of tubular structures with a minimum wall thickness as thin as 50 micrometers.By controlling the width of fine slits at the printing window,we achieved the printing of structures with a minimum feature size of 10 micrometers.Our process accomplished the fabrication of thin-walled tubular graft structure with a thickness of only 100 micrometers and lengths of several centimeters within a timeframe of just 100 s.Additionally,it enables the printing of axial multi-material structures,thereby achieving adjustable mechanical strength.This method is conducive to rapid customization of tubular grafts and the manufacturing of tubular components in fields such as dentistry,aerospace,and more.
文摘A low-cost 1D cobalt-based coordination polymer(CP)[Co(BGPD)(DMSO)_(2)(H_(2)O)_(2)](Co-BD;H2BGPD=N,N'-bis(glycinyl)pyromellitic diimide;DMSO=dimethyl sulfoxide)was synthesized by a simple method,and its crystal structure was characterized.In a three-electrode system,Co-BD,as the electrode material for supercapacitors,achieved a specific capacitance of 830 F·g^(-1)at 1 A·g^(-1),equivalent to a specific capacity of 116.4 mAh·g^(-1),and exhibited high-rate capability,reaching 212 F·g^(-1)at 20 A·g^(-1).Impressively,Co-BD||rGO(reduced graphene oxide),representing an asymmetrical supercapacitor,owns a higher energy density of 14.2 Wh·kg^(-1)at 0.80 kW·kg^(-1),and an excellent cycle performance(After 4000 cycles at 1 A·g^(-1),the capacitance retention was up to 94%).CCDC:2418872.
基金Supported by National Natural Science Foundation of China (Grant Nos.52235011,51905352)Shenzhen Municipal Excellent Science and Technology Creative Talent Training Program (Grant No.RCBS20210609103819021)+1 种基金Guangdong Provincial Basic and Applied Basic Research Foundation (Grant No.2023B1515120086)Shenzhen Municipal Science and Technology Planning Project (Grant No.CJGJZD20230724093600001)。
文摘Titanium and its alloys have been widely applied in many biomedical fields because of its excellent mechanical properties,corrosion resistance and good biocompatibility.However,problems such as rejection,shedding and infection will occur after titanium alloy implantation due to the low biological activity of titanium alloy surface.The structures with specific functions,which can enhance osseointegration and antibacterial properties,are fabricated on the surface of titanium implants to improve the biological activity between the titanium implants and human tissues.This paper presents a comprehensive review of recent developments and applications of surface functional structure in titanium and titanium alloy implants.The applications of surface functional structure on different titanium and titanium alloy implants are introduced,and their manufacturing technologies are summarized and compared.Furthermore,the fabrication of various surface functional structures used for titanium and titanium alloy implants is reviewed and analyzed in detail.Finally,the challenges affecting the development of surface functional structures applied in titanium and titanium alloy implants are outlined,and recommendations for future research are presented.
