The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when th...The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.展开更多
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(...Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3.展开更多
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'...Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.展开更多
Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mech...Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mechanisms underlying these processes remain incompletely understood.Iron is an essential trace element in the human body,playing a crucial role in various biological processes.The maintenance of iron homeostasis relies on the body's intricate and nuanced regulatory mechanisms.In recent years,considerable attention has been directed toward the relationship between dysregulated iron homeostasis and neurodegenerative diseases.The regulation of iron homeostasis within cells is crucial for maintaining proper nervous system function.Research has already revealed that disruptions in iron homeostasis may lead to ferroptosis and oxidative stress,which,in turn,can impact neuronal health and contribute to the development of neurodegenerative diseases.This article primarily explores the intimate relationship between iron homeostasis and neurodegenerative diseases,aiming to provide novel insights and strategies for treating these debilitating conditions.展开更多
Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been construc...Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3.展开更多
Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presen...Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presents significant challenges.In this study,a novel research method was introduced for investigating the solidification process of ductile iron pipe,namely thermal simulation of ductile iron pipe.Comparative research was conducted on the microstructure and properties of the thermal simulation sample and the ductile iron pipe.The findings indicate that the thermal simulation sample and ductile iron pipe exhibit good heat transfer similarity and microstructure similarity.The difference of cooling rate between thermal simulation sample and ductile pipe is less than 0.24℃·s^(-1),and the difference of microstructure content of free cementite,ferrite,and pearlite is less than 5%.The tensile strength of annealed ductile iron pipe is 466 MPa,with an elongation of 16.1%and a Brinell hardness of 156.5 HBW.In comparison,the tensile strength of annealed thermal simulation sample is 482.0 MPa,with an elongation of 15.5%and a Brinell hardness of 159.0 HBW.These results suggest that the thermal simulation experimental research method is both scientific and feasible,offering an objective,reliable,and cost-effective approach to laboratory research on ductile iron pipe.展开更多
With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely o...With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.展开更多
Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current ev...Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current evidence on diagnostic protocols and management strategies,highlighting optimal approaches and emerging trends.Initial care emphasizes soft tissue assessment,often guided by the Tscherne classification,and fracture classification systems.External fixation may be required in open injuries,while early open reduction and internal fixation within six days is linked to improved outcomes.Minimally invasive techniques for the lateral malleolus,including intramedullary nailing and locking plates,are effective,while medial malleolus fractures are commonly managed with screw fixation or tension-band wiring.Posterior malleolus fragments involving more than 25%of the articular surface usually warrant fixation.Alternatives to syndesmotic screws,such as cortical buttons or high-strength sutures,reduce the need for secondary procedures.Arthroscopic-assisted open reduction and internal fixation benefits younger,active patients by enabling concurrent management of intra-articular and ligamentous injuries.Postoperative care prioritizes early weight-bearing and validated functional scores.Despite advances,complications remain common,and further research is needed to refine surgical strategies and improve outcomes.展开更多
Dissolved black carbon(DBC)plays a crucial role in the migration and bioavailability of iron in water.However,the properties of DBC releasing under diverse pyrolysis conditions and dissolving processes have not been s...Dissolved black carbon(DBC)plays a crucial role in the migration and bioavailability of iron in water.However,the properties of DBC releasing under diverse pyrolysis conditions and dissolving processes have not been systematically studied.Here,the compositions of DBC released from biochar through redox processes dominated by bacteria and light were thoroughly studied.It was found that the DBC released from straw biochar possess more oxygen-containing functional groups and aromatic substances.The content of phenolic and carboxylic groups in DBC was increased under influence of microorganisms and light,respectively.The concentration of phenolic hydroxyl groups increased from 10.0~57.5 mmol/gC to 6.6~65.2 mmol/gC,and the concentration of carboxyl groups increased from49.7~97.5 mmol/gC to 62.1~113.3 mmol/gC.Then the impacts of DBC on pyrite dissolution andmicroalgae growth were also investigated.The complexing Fe^(3+)was proved to play a predominant role in the dissolution of ferrous mineral in DBC solution.Due to complexing between iron ion and DBC,the amount of dissolved Fe in aquatic water may rise as a result of elevated number of aromatic components with oxygen containing groups and low molecular weight generated under light conditions.Fe-DBC complexations in solution significantly promoted microalga growth,which might be attributed to the stimulating effect of dissolved Fe on the chlorophyll synthesis.The results of study will deepen our understanding of the behavior and ultimate destiny of DBC released into an iron-rich environment under redox conditions.展开更多
Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in hu...Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.展开更多
To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(...To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2.展开更多
Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mon...Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mononuclear complex due to the difference of their electronegativities,and coordination capabilities.Herein,we report a novel sulfur-phosphine co-coordinated heterogeneous Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)&S),which exhibits an unexpected 1.5–2.0 times catalytic activity for hydroformylation of olefins(C_(3)=,C_(5)=–C_(8)=),in comparison with the solely phosphine-coordinated Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)).In contrast,sulfur coordination alone leads to severe sulfur poisoning with significantly inhibited catalytic performance.Experimental and theoretical analyses reveal that phosphine coordination promotes catalytic activity via its strong electron-donating ability,while sulfur occupies a coordination site and reduces the electronic density of Rh ions.The synergistical coordination of sulfur and phosphine optimizes the electronic density of active Rh ions and decreases the energy barrier of the rate-determining step of olefin insertion,thus enhancing the hydroformylation activity,regioselectivity and stability of Rh_(1)/POPs-PPh_(3)&S.展开更多
To investigate the therapeutic effects of angelica sinensis polysaccharide-iron complex （APIC） on hemolytic anemia and bone marrow injury in mice models. The hemolytic anemia mouse model was established by i.p. of p...To investigate the therapeutic effects of angelica sinensis polysaccharide-iron complex （APIC） on hemolytic anemia and bone marrow injury in mice models. The hemolytic anemia mouse model was established by i.p. of phenylhydrazine （PHZ）. Changes of the indices including red blood cell count （RBC）, hemoglobin （Hb） and hematocrit （HCT） were determined by blood analyzer, and reticulocytes were observed by brilliant cresol blue staining during administration. Bone marrow injured mouse model was established by i.p. of cytoxan （CY） and chloramphenicol （CH）, and the therapeutic effect was observed by H-E staining. The indices of APIC treated groups with the medium and high doses were higher than those of the model group significantly. Moreover, the Hb and HCT were restored to the normal level after drug treatments. In addition, APIC can promote the proliferation and differentiation of reticulocytes obviously in the early stage of anemia mice, decrease adipose cell proliferation in bone marrow of injured mice and hasten the recuperation. In conclusion, APIC has therapeutic efficacy on hemolytic anemia and bone marrow injury caused by chemicals, which is reported for the first time.展开更多
To explore the mechanism of carbonyl iron flake composites for microwave complex permeability, this paper investigates the feature of the flakes. The shape anisotropy was certified by the results of the magnetization ...To explore the mechanism of carbonyl iron flake composites for microwave complex permeability, this paper investigates the feature of the flakes. The shape anisotropy was certified by the results of the magnetization hysteresis loops and the Mossbauer spectra. Furthermore, the shape anisotropy was used to explain the origin of composite microwave performance, and the calculated results agree with the experiment. It is believed that the shape anisotropy dominates microwave complex permeability, and the natural resonance plays main role in flake.展开更多
The kinetics of isothermal reduction of the carbon bearing pellets, which were mainly composed of Bayanobo complex iron ore and pulverized coal, was investigated by thermogravimetry at the temperature of 1 273-1 673 K...The kinetics of isothermal reduction of the carbon bearing pellets, which were mainly composed of Bayanobo complex iron ore and pulverized coal, was investigated by thermogravimetry at the temperature of 1 273-1 673 K. The effects of xC/xO and the atmospheres on the extent of reduction also were investigated. The results indicate that the fractional reaction increased proportionally with temperature increasing and heating temperature is the significant influence factor to the reaction of carbon bearing pellets. The optimum xC/xO is 1.2 and the effect of atmosphere on the reduction of iron oxides is almost negligible. The results can be interpreted that the reaction was initially controlled by a mixed controlled mechanism of carbon gasification and interface chemical reaction, and in the later stage, interface chemical reaction became the rate-controlling step. Apparent activation energy values of reduction at different levels of fractional reaction were calculated. Before F （fraction of reaction）=0.5, the apparent activation energy ranges from 66.39 to 75.64 kJ/mol, while after F=0.5, the apparent activation energy is 80.98 to 85.37 kJ/mol.展开更多
A robust voltammetric method has been developed and validated for the determination of Fe（Ⅱ） and Fe（Ⅲ） in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concen...A robust voltammetric method has been developed and validated for the determination of Fe（Ⅱ） and Fe（Ⅲ） in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concentration about 3% in the pharmaceutical formulation, can be easily determined with good accuracy and precision. This methodology can be proposed as a viable, environmentally sustainable substitute for the conventional Normal Pulse Polarographic method in US Pharmacopeia, with better analytical figures of merit, and reduced Hg consumption. A deeper insight in Fe（Ⅱ） and Fe（Ⅲ） composition can be gained by the combined use of a new potentiometric technique after chemical decomposition of the complex.展开更多
The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the micro...The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.展开更多
A series of pyrazolylimine ligated Co(II) and Fe(II) complexes with general formula of(PhC=N(C_6H_3(R_1)2-2,6)(C_3 HN_2(R_2)2-3,5)MtCl_2(R_1 = Me, R_2 = H, Mt = Co(1 a), Fe(2 a); R_1 = Me, R_2 = Me, Mt = Co(1b), Fe(2b...A series of pyrazolylimine ligated Co(II) and Fe(II) complexes with general formula of(PhC=N(C_6H_3(R_1)2-2,6)(C_3 HN_2(R_2)2-3,5)MtCl_2(R_1 = Me, R_2 = H, Mt = Co(1 a), Fe(2 a); R_1 = Me, R_2 = Me, Mt = Co(1b), Fe(2b); R_1 = iPr, R_2 = H, Mt = Co(1 c), Fe(2 c); R_1 = i Pr, R_2 = Me, Mt = Co(1 d), Fe(2 d); R_1 = i Pr, R_2 = Ph, Mt = Co(1 e), Fe(2 e)) were synthesized and thoroughly characterized.Determined by single crystal X-ray diffraction, complexes 1 b and 2 b revealed dimeric structures, in which distorted trigonal bipyramid geometries were adopted for each metal centers. In the presence of ethylaluminum sesquichloride(EASC), all the cobalt complexes displayed high activities in 1,3-butadiene polymerization, affording polybutadienes with predominant cis-1,4 contents(up to 97.0%).Influences of ligand structure and polymerization parameters on catalytic performance were investigated systematically. For pyrazolylimine iron(II) dichloride complexes, the catalytic activities and microstructures of the resultant polybutadienes were highly dependent on ligand structures and polymerization conditions. For complex 2 a, changing cocatalyst from trialkyl aluminums to methyl aluminoxane(MAO) led to an shift of selectivity from high cis-1,4-to trans-1,4-/1,2-manner. Being activated by MAO, complexes 2 a and 2 b gave trans-1,4-/1,2-binary polybutadienes, while complexes 2 c, 2 d, and 2 e afforded cis-1,4-enriched polymers.展开更多
The cerium iron complex oxides oxygen carrier was prepared by the co-precipitation method. The reactions between methane and lattice oxygen from the complex oxides were investigated in a fixed micro-reactor system. Th...The cerium iron complex oxides oxygen carrier was prepared by the co-precipitation method. The reactions between methane and lattice oxygen from the complex oxides were investigated in a fixed micro-reactor system. The reduced oxygen carder could be re-oxidized by air and its initial state could be restored. The characterizations of the oxygen carders were studied using XRD, O2-TPD, and H2-TPR. The results showed that the bulk lattice oxygen of CeO2-Fe2O3 was found to be suitable for the partial oxidation of methane to synthesis gas. There were two kinds of oxygen species on the oxygen carrier： the stronger oxygen species that was responsible for the complete oxidation of methane, and the weaker oxygen species （bulk lattice oxygen） that was responsible for the selective oxidation of methane to CO and H2 at a higher temperature. Then, the lost bulk lattice oxygen could be selectively supplemented by air re-oxidation at an appropriate reaction condition. CeFeO3 appeared on the oxygen carrier after 10 successive redox cycles, however, it was not bad for the selectivity of CO and H2.展开更多
文摘The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.
文摘Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3.
文摘Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.
基金supported in part by the National Natural Science Foundation of China,No.82371153(to YS)the Natural Science Foundation of Shandong Province,Nos.ZR2021MH378,ZR2022QH073(to LC)+1 种基金the Shandong Society of Geriatric Science and Technology Project,No.LKJGG2021Z020(to YS)the Yantai Science and Technology Innovation Development Project,Nos.2022YD009,2023YD050。
文摘Neurodegenerative diseases are prevalent conditions that greatly impact human health.These diseases are primarily characterized by the progressive loss and eventual death of neuronal function,although the precise mechanisms underlying these processes remain incompletely understood.Iron is an essential trace element in the human body,playing a crucial role in various biological processes.The maintenance of iron homeostasis relies on the body's intricate and nuanced regulatory mechanisms.In recent years,considerable attention has been directed toward the relationship between dysregulated iron homeostasis and neurodegenerative diseases.The regulation of iron homeostasis within cells is crucial for maintaining proper nervous system function.Research has already revealed that disruptions in iron homeostasis may lead to ferroptosis and oxidative stress,which,in turn,can impact neuronal health and contribute to the development of neurodegenerative diseases.This article primarily explores the intimate relationship between iron homeostasis and neurodegenerative diseases,aiming to provide novel insights and strategies for treating these debilitating conditions.
文摘Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3.
基金financially supported by the National Natural Science Foundation of China(52130109)。
文摘Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presents significant challenges.In this study,a novel research method was introduced for investigating the solidification process of ductile iron pipe,namely thermal simulation of ductile iron pipe.Comparative research was conducted on the microstructure and properties of the thermal simulation sample and the ductile iron pipe.The findings indicate that the thermal simulation sample and ductile iron pipe exhibit good heat transfer similarity and microstructure similarity.The difference of cooling rate between thermal simulation sample and ductile pipe is less than 0.24℃·s^(-1),and the difference of microstructure content of free cementite,ferrite,and pearlite is less than 5%.The tensile strength of annealed ductile iron pipe is 466 MPa,with an elongation of 16.1%and a Brinell hardness of 156.5 HBW.In comparison,the tensile strength of annealed thermal simulation sample is 482.0 MPa,with an elongation of 15.5%and a Brinell hardness of 159.0 HBW.These results suggest that the thermal simulation experimental research method is both scientific and feasible,offering an objective,reliable,and cost-effective approach to laboratory research on ductile iron pipe.
文摘With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.
文摘Complex trimalleolar ankle fractures are a major orthopaedic challenge,with an incidence of 4.22 per 10000 person-years in the United States and an annual cost of 3.4 billion dollars.This review synthesizes current evidence on diagnostic protocols and management strategies,highlighting optimal approaches and emerging trends.Initial care emphasizes soft tissue assessment,often guided by the Tscherne classification,and fracture classification systems.External fixation may be required in open injuries,while early open reduction and internal fixation within six days is linked to improved outcomes.Minimally invasive techniques for the lateral malleolus,including intramedullary nailing and locking plates,are effective,while medial malleolus fractures are commonly managed with screw fixation or tension-band wiring.Posterior malleolus fragments involving more than 25%of the articular surface usually warrant fixation.Alternatives to syndesmotic screws,such as cortical buttons or high-strength sutures,reduce the need for secondary procedures.Arthroscopic-assisted open reduction and internal fixation benefits younger,active patients by enabling concurrent management of intra-articular and ligamentous injuries.Postoperative care prioritizes early weight-bearing and validated functional scores.Despite advances,complications remain common,and further research is needed to refine surgical strategies and improve outcomes.
基金supported by the National Natural Science Foundation of China(Nos.42207450,42067056,and 21866017)the Yunnan Fundamental Research Projects(No.202101BE070001-013)the Foundation for Distinguished Young Talents of Yunnan Province(No.202101AV070006).
文摘Dissolved black carbon(DBC)plays a crucial role in the migration and bioavailability of iron in water.However,the properties of DBC releasing under diverse pyrolysis conditions and dissolving processes have not been systematically studied.Here,the compositions of DBC released from biochar through redox processes dominated by bacteria and light were thoroughly studied.It was found that the DBC released from straw biochar possess more oxygen-containing functional groups and aromatic substances.The content of phenolic and carboxylic groups in DBC was increased under influence of microorganisms and light,respectively.The concentration of phenolic hydroxyl groups increased from 10.0~57.5 mmol/gC to 6.6~65.2 mmol/gC,and the concentration of carboxyl groups increased from49.7~97.5 mmol/gC to 62.1~113.3 mmol/gC.Then the impacts of DBC on pyrite dissolution andmicroalgae growth were also investigated.The complexing Fe^(3+)was proved to play a predominant role in the dissolution of ferrous mineral in DBC solution.Due to complexing between iron ion and DBC,the amount of dissolved Fe in aquatic water may rise as a result of elevated number of aromatic components with oxygen containing groups and low molecular weight generated under light conditions.Fe-DBC complexations in solution significantly promoted microalga growth,which might be attributed to the stimulating effect of dissolved Fe on the chlorophyll synthesis.The results of study will deepen our understanding of the behavior and ultimate destiny of DBC released into an iron-rich environment under redox conditions.
基金supported by the National Key R&D Program of China,Nos.2017YFA0104302(to NG and XM)and 2017YFA0104304(to BW and ZZ)
文摘Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury.
文摘To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2.
文摘Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mononuclear complex due to the difference of their electronegativities,and coordination capabilities.Herein,we report a novel sulfur-phosphine co-coordinated heterogeneous Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)&S),which exhibits an unexpected 1.5–2.0 times catalytic activity for hydroformylation of olefins(C_(3)=,C_(5)=–C_(8)=),in comparison with the solely phosphine-coordinated Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)).In contrast,sulfur coordination alone leads to severe sulfur poisoning with significantly inhibited catalytic performance.Experimental and theoretical analyses reveal that phosphine coordination promotes catalytic activity via its strong electron-donating ability,while sulfur occupies a coordination site and reduces the electronic density of Rh ions.The synergistical coordination of sulfur and phosphine optimizes the electronic density of active Rh ions and decreases the energy barrier of the rate-determining step of olefin insertion,thus enhancing the hydroformylation activity,regioselectivity and stability of Rh_(1)/POPs-PPh_(3)&S.
基金Foundation of Science and Technology Department of Hubei Province(Grant No.2005AA301C04)
文摘To investigate the therapeutic effects of angelica sinensis polysaccharide-iron complex （APIC） on hemolytic anemia and bone marrow injury in mice models. The hemolytic anemia mouse model was established by i.p. of phenylhydrazine （PHZ）. Changes of the indices including red blood cell count （RBC）, hemoglobin （Hb） and hematocrit （HCT） were determined by blood analyzer, and reticulocytes were observed by brilliant cresol blue staining during administration. Bone marrow injured mouse model was established by i.p. of cytoxan （CY） and chloramphenicol （CH）, and the therapeutic effect was observed by H-E staining. The indices of APIC treated groups with the medium and high doses were higher than those of the model group significantly. Moreover, the Hb and HCT were restored to the normal level after drug treatments. In addition, APIC can promote the proliferation and differentiation of reticulocytes obviously in the early stage of anemia mice, decrease adipose cell proliferation in bone marrow of injured mice and hasten the recuperation. In conclusion, APIC has therapeutic efficacy on hemolytic anemia and bone marrow injury caused by chemicals, which is reported for the first time.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 90505007 and 10774061)
文摘To explore the mechanism of carbonyl iron flake composites for microwave complex permeability, this paper investigates the feature of the flakes. The shape anisotropy was certified by the results of the magnetization hysteresis loops and the Mossbauer spectra. Furthermore, the shape anisotropy was used to explain the origin of composite microwave performance, and the calculated results agree with the experiment. It is believed that the shape anisotropy dominates microwave complex permeability, and the natural resonance plays main role in flake.
基金Sponsored by National Key Technology Research and Development Program of China(2008BAB32B05)Postdoctoral Science Foundation of China(2012m510320)
文摘The kinetics of isothermal reduction of the carbon bearing pellets, which were mainly composed of Bayanobo complex iron ore and pulverized coal, was investigated by thermogravimetry at the temperature of 1 273-1 673 K. The effects of xC/xO and the atmospheres on the extent of reduction also were investigated. The results indicate that the fractional reaction increased proportionally with temperature increasing and heating temperature is the significant influence factor to the reaction of carbon bearing pellets. The optimum xC/xO is 1.2 and the effect of atmosphere on the reduction of iron oxides is almost negligible. The results can be interpreted that the reaction was initially controlled by a mixed controlled mechanism of carbon gasification and interface chemical reaction, and in the later stage, interface chemical reaction became the rate-controlling step. Apparent activation energy values of reduction at different levels of fractional reaction were calculated. Before F （fraction of reaction）=0.5, the apparent activation energy ranges from 66.39 to 75.64 kJ/mol, while after F=0.5, the apparent activation energy is 80.98 to 85.37 kJ/mol.
基金supported by FAR, Fondo Ateneoper la Ricerca Universitá di Pavia,Italy
文摘A robust voltammetric method has been developed and validated for the determination of Fe（Ⅱ） and Fe（Ⅲ） in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concentration about 3% in the pharmaceutical formulation, can be easily determined with good accuracy and precision. This methodology can be proposed as a viable, environmentally sustainable substitute for the conventional Normal Pulse Polarographic method in US Pharmacopeia, with better analytical figures of merit, and reduced Hg consumption. A deeper insight in Fe（Ⅱ） and Fe（Ⅲ） composition can be gained by the combined use of a new potentiometric technique after chemical decomposition of the complex.
基金financially supported by the National Science Foundation of China(Nos.51974212 and 52274316)the China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202116)+1 种基金the Science and Technology Major Project of Wuhan(No.2023020302020572)the Foundation of Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education(No.FMRUlab23-04)。
文摘The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.
基金financially supported by the National Basic Research Program of China(No.2015CB654700(2015CB654702))the National Natural Science Foundation of China(No.21801236)
文摘A series of pyrazolylimine ligated Co(II) and Fe(II) complexes with general formula of(PhC=N(C_6H_3(R_1)2-2,6)(C_3 HN_2(R_2)2-3,5)MtCl_2(R_1 = Me, R_2 = H, Mt = Co(1 a), Fe(2 a); R_1 = Me, R_2 = Me, Mt = Co(1b), Fe(2b); R_1 = iPr, R_2 = H, Mt = Co(1 c), Fe(2 c); R_1 = i Pr, R_2 = Me, Mt = Co(1 d), Fe(2 d); R_1 = i Pr, R_2 = Ph, Mt = Co(1 e), Fe(2 e)) were synthesized and thoroughly characterized.Determined by single crystal X-ray diffraction, complexes 1 b and 2 b revealed dimeric structures, in which distorted trigonal bipyramid geometries were adopted for each metal centers. In the presence of ethylaluminum sesquichloride(EASC), all the cobalt complexes displayed high activities in 1,3-butadiene polymerization, affording polybutadienes with predominant cis-1,4 contents(up to 97.0%).Influences of ligand structure and polymerization parameters on catalytic performance were investigated systematically. For pyrazolylimine iron(II) dichloride complexes, the catalytic activities and microstructures of the resultant polybutadienes were highly dependent on ligand structures and polymerization conditions. For complex 2 a, changing cocatalyst from trialkyl aluminums to methyl aluminoxane(MAO) led to an shift of selectivity from high cis-1,4-to trans-1,4-/1,2-manner. Being activated by MAO, complexes 2 a and 2 b gave trans-1,4-/1,2-binary polybutadienes, while complexes 2 c, 2 d, and 2 e afforded cis-1,4-enriched polymers.
基金the National Natural Science Foundation of China (50574046)National Natural Science Foundation of Major Research Projects (90610035)+1 种基金Natural Science Foundation of Yunnan Province (2004E0058Q)High School Doctoral Subject Special Science and Research Foundation of Ministry of Education (20040674005)
文摘The cerium iron complex oxides oxygen carrier was prepared by the co-precipitation method. The reactions between methane and lattice oxygen from the complex oxides were investigated in a fixed micro-reactor system. The reduced oxygen carder could be re-oxidized by air and its initial state could be restored. The characterizations of the oxygen carders were studied using XRD, O2-TPD, and H2-TPR. The results showed that the bulk lattice oxygen of CeO2-Fe2O3 was found to be suitable for the partial oxidation of methane to synthesis gas. There were two kinds of oxygen species on the oxygen carrier： the stronger oxygen species that was responsible for the complete oxidation of methane, and the weaker oxygen species （bulk lattice oxygen） that was responsible for the selective oxidation of methane to CO and H2 at a higher temperature. Then, the lost bulk lattice oxygen could be selectively supplemented by air re-oxidation at an appropriate reaction condition. CeFeO3 appeared on the oxygen carrier after 10 successive redox cycles, however, it was not bad for the selectivity of CO and H2.
