We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),campho...We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5.展开更多
The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively red...The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.展开更多
Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compou...Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compounds as host material,high efficiency solution-processed green phosphorescent organic light-emitting diodes(PhOLEDs)have been achieved.The high triplet energies of TBICz and TOXDCz ensure efficient energy transfer from the host to the phosphor and triplet exciton confinement on the phosphor.Solution-processable green phospho⁃rescent devices employing Ir(ppy)3 as guest and the two tetrasubstituted carbazole derivatives as hosts exhibit high ef⁃ficiencies.The best EL performance is achieved for the TBICz-based device,with a maximum current efficiency of 27.3 cd/A,a maximum power efficiency of 15.9 lm/W,and a maximum external quantum efficiency of 7.8%,which provides more host material options for solution-processed OLEDs.展开更多
To further investigate the one-dimensional(1D)rheological consolidation mechanism of double-layered soil,the fractional derivative Merchant model(FDMM)and the non-Darcian flow model with the non-Newtonian index are re...To further investigate the one-dimensional(1D)rheological consolidation mechanism of double-layered soil,the fractional derivative Merchant model(FDMM)and the non-Darcian flow model with the non-Newtonian index are respectively introduced to describe the deformation of viscoelastic soil and the flow of pore water in the process of consolidation.Accordingly,an 1D rheological consolidation equation of double-layered soil is obtained,and its numerical analysis is performed by the implicit finite difference method.In order to verify its validity,the numerical solutions by the present method for some simplified cases are compared with the results in the related literature.Then,the influence of the revelent parameters on the rheological consolidation of double-layered soil are investigated.Numerical results indicate that the parameters of non-Darcian flow and FDMM of the first soil layer greatly influence the consolidation rate of double-layered soil.As the decrease of relative compressibility or the increase of relative permeability between the lower soil and the upper soil,the dissipation rate of excess pore water pressure and the settlement rate of the ground will be accelerated.Increasing the relative thickness of soil layer with high permeability or low compressibility will also accelerate the consolidation rate of double-layered soil.展开更多
Most of the existing multivariable grey models are based on the 1-order derivative and 1-order accumulation, which makes the parameters unable to be adjusted according to the data characteristics of the actual problem...Most of the existing multivariable grey models are based on the 1-order derivative and 1-order accumulation, which makes the parameters unable to be adjusted according to the data characteristics of the actual problems. The results about fractional derivative multivariable grey models are very few at present. In this paper, a multivariable Caputo fractional derivative grey model with convolution integral CFGMC(q, N) is proposed. First, the Caputo fractional difference is used to discretize the model, and the least square method is used to solve the parameters. The orders of accumulations and differential equations are determined by using particle swarm optimization(PSO). Then, the analytical solution of the model is obtained by using the Laplace transform, and the convergence and divergence of series in analytical solutions are also discussed. Finally, the CFGMC(q, N) model is used to predict the municipal solid waste(MSW). Compared with other competition models, the model has the best prediction effect. This study enriches the model form of the multivariable grey model, expands the scope of application, and provides a new idea for the development of fractional derivative grey model.展开更多
OBJECTIVE To identify the specific targets of a novel derivative of Danshensu ADTM as the protein disulfide isomerase(PDI)family proteins including ERp57.To further investigate the underlying mechanism of ADTM to modu...OBJECTIVE To identify the specific targets of a novel derivative of Danshensu ADTM as the protein disulfide isomerase(PDI)family proteins including ERp57.To further investigate the underlying mechanism of ADTM to modulate ERp57 to regulate platelet function with direct interaction withαⅡbβ3 integrin.METHODS To isolate the protein targets that bound to ADTM,a biotin-conjugated ADTM analogue(BAA)was designed and synthesized.BAA(300μmol·L-1)was incubated with rat blood platelet lysates and the BAA-protein complexes were pulled down with NeutrAvidin-agarose followed by protein profiling using LC-MS/MS.To determine platelet aggregation in vitro,rabbit platelets were incubated with the indicated concentrations of compounds and aggregation was induced by ADP(10μmol·L-1)or AA(200μmol·L-1)and measured using a platelet aggregometer.To determine platelet aggregation-induced by ADP in rat in vivo,ADTM(5-20mg·kg-1)in comparison with DSS(10mg·kg-1)and clopidogrel(18mg·kg-1)were administered daily by i.v.injection for 5d,respectively.To determine the action of ADTM on the ERp57/αⅡbβ3 interaction,it was examined by immunoprecipitation with anti-αⅡbβ3antibody,followed by detection of ERp57 immunoreactivity using immunoblotting.RESULTS BAA could bind to various proteins involved in platelet function.In particular,platelet aggregation-associated proteins were identified with>95% protein identification probability including ERp72,ERp57ERp5 and PDI,which are members of the protein disulfide isomerase(PDI)family related to platelet function and redox homeostasis.ADTM exhibited potent inhibition on the redox activity of ERp57 in a concentration-dependent manner(IC50=100 300μmol·L-1).In in vitro studies,ADTM exhibited concentration-dependent inhibition on ADP-induced and AA-induced platelet aggregation with comparable effects to aspirin and clopidogrel.In vivo study showed that ADP-induced platelet aggregation was significantly compromised(>40%reduction)in rats treated with ADTM(20mg·kg-1).Similarly,ADTM also exhibited significant anti-thrombotic effect in vivo as shown in the ferric chloride(FeCl3)-induced venous thrombosis.Immunoprecipitation with anti-αⅡbβ3antibody,followed by detection of ERp57 immunoreactivity using immunoblotting showed that ADTM disrupted the interaction of ERp57 with αⅡ bβ3.CONCLUSION These results demonstrated that ADTM exhibited broad-spectrum anti-platelet activities and ERp57 is a potential therapeutic target for anti-platelet therapy.展开更多
Accurately evaluating the aerodynamic performance of a battle-structure-damaged aircraft is essential to enable the pilot to optimize the flight control strategy. Based on CFD and rigid dynamic mesh techniques,a numer...Accurately evaluating the aerodynamic performance of a battle-structure-damaged aircraft is essential to enable the pilot to optimize the flight control strategy. Based on CFD and rigid dynamic mesh techniques,a numerical method is developed to calculate the longitudinal and longitudinal-lateral coupling forces and moments with small amplitude sinusoidal pitch oscillation, and the corresponding dynamic derivatives of two fragment-structure-damaged and two continuous-rod-damaged models modified from the SACCON UAV. The results indicate that, at the reference point set in this paper, additional positive damping is generated in fragment-damaged configurations;thus, the absolute values of the negative pitch dynamic derivative increase. The missing wingtip induces negative pitch damping on the aircraft and decreases the value of the pitch dynamic derivative. The missing middle wing causes a noticeable increase in the absolute value of the pitch dynamic derivative;the missing parts on the right wing cause the aircraft to roll to the right side in the dynamic process, and the pitch-roll coupling cross dynamic derivatives are positive. Moreover, the values of these derivatives increase as the damaged area on the right wing increases, and an optimal case with the smallest cross dynamic derivative can be found to help improve the survivability of damaged aircraft.展开更多
Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and...Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and characterized by infrared spectrometry, 1H nuclear magnetic resonance, elemental analysis and gas chromatograph-mass spectrometry. The ligand synthetic route was optimized. The fluorescence properties of the complex in solid state, in different kind of solvents and in solutions with different pH values were investigated in detail. The results show that the yields of DSPDA and 4-SPDA reach over 78% by Wittig-Horner reaction and other eight pyridine-2, 6-dicarboxylic acid derivatives with different substituents on pyridine ring, and their complexes with Tb(Ⅲ) are also obtained. The fluorescence intensities of the complexes with electron-donating groups are more intense than those of the complexes with electron-withdrawing groups on pyridine ring; fluorescence intensities of the complexes are the strongest in neutral solution (pH=7), and the less the dipole moment of solvent molecule is, the stronger the fluorescence intensity is. It is found that the two ligands (4-APDA and DSPDA) are the good sensitizers for Tb(Ⅲ) ion.展开更多
Reaction of Cp2TiCl2-Mg synthetic equivalent of practical Ti(II) reagent with propargyl alcohol derivatives affords allenyl titanium compounds in good yields.thus, providing an efficient and practical methods for synt...Reaction of Cp2TiCl2-Mg synthetic equivalent of practical Ti(II) reagent with propargyl alcohol derivatives affords allenyl titanium compounds in good yields.thus, providing an efficient and practical methods for synthesis of both allenyl and homopropargyl alcohols by the successive treatment with aldehydes and ketones.展开更多
A new general optimal principle of designing explicit finite difference method was obtained. Several applied cases were put forward to explain the uses of the principle. The validity of the principal was tested by a n...A new general optimal principle of designing explicit finite difference method was obtained. Several applied cases were put forward to explain the uses of the principle. The validity of the principal was tested by a numeric example.展开更多
Nine 5 (β substituted stylryl) salicyladehyde derivatives were prepared by PTC Witting reactions in the paper . The stereochemistry of the Witting reactions and the substituted effect on the UV spectra of salicylad...Nine 5 (β substituted stylryl) salicyladehyde derivatives were prepared by PTC Witting reactions in the paper . The stereochemistry of the Witting reactions and the substituted effect on the UV spectra of salicyladehyde derivaties have been reported . It was observed that the spectra undergo a red shift as the conjugative effect of substituted becomes stronger . A good linear relationship between the shift of UV of p substituted compounds and conjugation effect was obtained.It showed that the Hammett equation may be applied to the UV frequencies of the title compounds.展开更多
OBJECTIVE To analyse structure and relationship of several andrographolide derivatives in multiple in vivo and in vitro angiogenesis assays,and to demonstrate a novel compound named AGL-2as a potential anti-angiogenes...OBJECTIVE To analyse structure and relationship of several andrographolide derivatives in multiple in vivo and in vitro angiogenesis assays,and to demonstrate a novel compound named AGL-2as a potential anti-angiogenesis agent.METHODS Human umbilical vein endothelial cells(HUVECs)in vitro and zebrafish(Danio rerio)in vivo models were used to screen and identify the anti-angiogenesis activities of six andrographolide derivatives;namely,AGL-1,AGL-2,AGS-72,AGS-72 a,AGS-79 and AGP-151.RESULTS AGL-2exhibited the strongest anti-angiogenic activity among all the derivatives in zebrafish model.Interestingly,another compound named AGS-72 showed stronger anti-angiogenic activity than AGL-2 in VEGF-induced HUVECs proliferation,migration,invasion and tube formation assays.In addition,AGL-2 was found to suppress the VEGF-induced VEGFR-2auto-phosphorylation and inhibit the activity of VEGFR-2 mediated signaling cascades in a dose-dependent manner.CONCLUSION AGL-2was demonstrated to be a promising anti-angiogenic agent among all the tested derivatives.The mechanism underlying the anti-angiogenic activity of AGL-2 probably involve VEGFR-2 signaling pathway.Even though,how some of chemical structure alterations result in discrepancy between in vivo and in vitro activities still remains to be resolved,this study shall provide new insight into how modification of the chemical structure of andrographolide affects this newly identified anti-angiogenesis activity.Meanwhile,AGL-2 can be exploited as a potential therapeutic agent for the treatment of angiogenesis-related diseases.展开更多
It’s known to all that under ideal condition the s to rage cost is kept in lower level when storage management be arranged by Economic Order Quantity(EOQ).Does this mean that any companies should set up their own sto...It’s known to all that under ideal condition the s to rage cost is kept in lower level when storage management be arranged by Economic Order Quantity(EOQ).Does this mean that any companies should set up their own storing system in proportion to the scale of the commodities’ producing or sell ing Furthermore, even if they manage storage in EOQ, because of different oper ation scale, geographical condition or ability borrowing money from financial ma rket, different companies pay unequal cost in storing the same commodity.In thi s paper, except for supplying commodities from our own storage system, the autho rs have analyzed other two supplying ways without whole storage system, they are forward contracts and futures contracts.The authors have discussed variable su pply cost for above different supply measures.According to the cost of each sup ply way, the managers can choose the most economical way in supplying the commod ity and predict the price of futures from storage management arranged by EOQ.Th e summary content is as follow: 1. The comparing of supply cost between forward contracts and storing system a rranged by EOQ. (1) The supply cost from forward contracts (2) The supply cost from storage system arranged by Economic Order Quantity (3) The application example for comparing cost in different supply way 2.The comparing of supply cost between futures going physical and storing syst em arranged by Economic Order Quantity. (1) The supply cost from futures going physical (2) The correlation between futures contracts and storage management arranged b y EOQ (3) The application example for comparing cost in different supply way 3.How does storing system of scale economic affect the price of forward and fu tures contracts (1) How does the price of forward and futures contracts fluctuate (2) How do we calculate the price of a commodity at future point from the cost of scale economic storing (3) How do we operate efficiently in derivatives market by using the cost of sc ale economic storing (4) The application example for analyzing the price of futures 4.The correlation among storage managementforward contracts and futures mark et.展开更多
Six furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants have been investigated.It was shown that the use of some furazano-[3,4-d]-pyridazine-based derivatives as main compoun...Six furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants have been investigated.It was shown that the use of some furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants can considerably increase ballistic parameters compared with HMX if the compounds under consideration contain difluoramine groups.And the use of the compounds under consideration may be successful only in the presence of an active binder and 10%-30% of AP or ADN as additional oxidizers.展开更多
This study presents the synthesis of three dinuclear cobalt complexes based on three imine derivatives:bis-[4-(2-pyridylmethyleneamino)-phenyl]thioether(L1),bis-[4-(2-pyridylmethyleneamino)-phenyl]ether(L2),and bis-[4...This study presents the synthesis of three dinuclear cobalt complexes based on three imine derivatives:bis-[4-(2-pyridylmethyleneamino)-phenyl]thioether(L1),bis-[4-(2-pyridylmethyleneamino)-phenyl]ether(L2),and bis-[4-(2-pyridylmethyleneamino)-phenyl]methane(L3).Single-crystal X-ray diffraction analysis reveals that the complexes[Co_(2)(L1)3](ClO_(4))4·2CH_(3)CN(1),[Co_(2)(L2)3](ClO_(4))4·2CH_(3)OH(2),and[Co_(2)(L3)3](ClO_(4))4·2CH_(3)OH(3)all exhibit a dinuclear structure.Magnetic test results show that complex 3 exhibited irreversible SCO behavior induced by loss of solvent at 300 K,with the average Co-N bond length increasing from 0.2139(3)to 0.2153(3)nm.Meanwhile,the desolvated complex 3 exhibited paramagnetic behavior similar to that of complexes 1 and 2.Variable-temperature UV-Vis spectroscopic studies also indicate that complex 3 undergoes a solvent-loss-induced spin-state transition.CCDC:2347354,1(120 K);2347355,2(120 K);2347356,3(120 K);2347357,3(400 K).展开更多
OBJECTIVE Pulmonary artery hypertension(PAH)is a severe disease characterized by the mean pulmonary artery pressure exceeding 25 mm Hg at rest.PAH could induce right heart failure and has a very high mortality rate.At...OBJECTIVE Pulmonary artery hypertension(PAH)is a severe disease characterized by the mean pulmonary artery pressure exceeding 25 mm Hg at rest.PAH could induce right heart failure and has a very high mortality rate.At present,several kinds of drugs have been used in the treatment of PAH.However,most of these drugs aim to relax pulmonary arteries and do not inhibit the injury of vessels.In other words,the drugs available for PAH treatment do not improve the survival rate of PAH patients and cannot satisfy the needs in clinic.To discover and develop novel candidate compounds effective on the treatment of pulmonary artery injury and remodeling will be very important.Based on these background,the present study aimed to study the protective effect of two novel Rho-kinases(Rho-associated coiledcoil forming protein serine/threonine kinase,ROCK)inhibitors,DL0805 derivatives(DL0805-1and DL0805-2),on pulmonary arterial cells and further evaluate the underlying mechanisms and the possibility of DL0805 derivatives become therapeutic drugs for PAH.METHODS The primary cultured pulmonary arterial cells including human pulmonary artery endothelium cells(HPAECs)and human pulmonary artery smooth muscle cells(HPASMCs)were used in this study.HPAECs were injured under hypoxia environment(1%O2)and treated with or without DL0805 derivatives.After 48 h,the proliferation and oxidative stress were observed.CCK8 was used to detect cell viability.DCFH-DA was used as probe for reactive oxygen species(ROS)under fluorescence imaging system.HPASMCs was stimulated by growth factors including platelet-derived growth factor-BB(PDGF-BB)and Fetal Bovine Serum(FBS).The proliferation was observed in the cells treated with or without DL0805 derivatives.HPASMCs treated with or without DL0805 derivatives were further incubated with endothelin(ET-1),the proliferation and cytoskeleton remodeling of cells were detected by immunofluorescence assay.At last,Western blotting(WB)and immunofluorescence assay were employed to analysis the underlying mechanisms in the above experiments.RESULTS 10μmol·L-1DL0805-2 could inhibit the proliferation of HPAECs induced by hypoxia.Each concentration of DL0805-1 and DL0805-2attenuated the production of ROS in HPAECs.Results from WB indicated that DL0805 derivatives decreased the injury of HPAECs induced by hypoxia through the inhibition of the expression of Rho A and the activity of ROCK.On HPASMCs,DL0805 derivatives reduced the proliferation induced by PDGF-BB and FBS and inhibited cytoskeleton remodeling induced by ET-1.Immunofluorescence assay showed that DL0805 derivatives inhibited ROCK activity and down regulated the phosphorylation levels of ROCK substrates.CONCLUSION DL0805derivatives exhibited protective effect on pulmonary arterial cells including endothelium cells and smooth muscle cells.Among the above experiments,DL0805-2 showed stronger potency than DL0805-1.These two compounds might protect the cells through the inhibition of Rho A/ROCK pathway and they probably have the potential in the treatment of PAH and deserve further evaluation.展开更多
OBJECTIVE To investigate the cardioprotective effect of novel danshensu derivatives against doxorubicin(Dox)cardiotoxicity and their synergistic anti-tumor effect with Dox on breast cancer cells.METHODS Two new Danshe...OBJECTIVE To investigate the cardioprotective effect of novel danshensu derivatives against doxorubicin(Dox)cardiotoxicity and their synergistic anti-tumor effect with Dox on breast cancer cells.METHODS Two new Danshensu derivatives were synthesized by conjugation with tetramethylpyrizine and/or4-(3-thioxo-3 H-1,2-dithiol-4-yl)-benzoic acid and tested for protective effects against Dox induced cardiotoxicity in cell and zebrafish.H9c2 cardiomyoblasts were co-treated with Dox and Danshensu derivatives for 24 h and then were measured for cell viability and cytotoxicity by MTT and LDH assays.The expression levels of mitochondrial biogenesis related proteins PGC-1α,NRF-1and Nrf2 were detected by Western blotting and qPCR.Moreover,in a Dox-induced cardiotoxicity model of zebrafish,zebrafish embryos were treated with Dox for 36 h,followed by measurement of numerous ventricular function parameters including heart rate,stroke volume,cardiac output and fractional shortening.In addition,the synergistic anti-tumor effects of the Danshensu derivatives and Dox had been studied in MCF-7 breast cancer cells.The effects of the Danshensu derivatives on the cell death and metabolism of MCF-7 cells were measured using apoptosis assay and Seahorse Metabolic Analyzers respectively.RESULTS Our results showed that the Danshensu derivatives were more potent than the parental compounds in ameliorating Dox-induced cytotoxicity in H9c2 cells and significantly preserving stroke volume of heart function in Dox-treated zebrafish.Further mechanistic studies identified that the danshensu derivatives increased mitochondrial copy numbers and protein expressions of PGC-1α,NRF-1 and Nrf2 in H9c2 cells.In addition,the Danshensu derivatives enhanced Dox-induced apoptosis,and decreased glycolysis and mitochondrial function in MCF-7 tumor cells.CONCLUSION Our results revealed that two new Danshensu derivatives displayed promising cardioprotective effects against Dox induced cardiotoxicity both in vivo and in vitro,at least partially through activating mitochondrial biogenesis.Also,the new Danshensu derivatives potentiated the anticancer effects of Dox in breast tumor cells involving induction of glycolytic inhibition and mitochondrial dysfunction.展开更多
文摘We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5.
文摘The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.
文摘Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compounds as host material,high efficiency solution-processed green phosphorescent organic light-emitting diodes(PhOLEDs)have been achieved.The high triplet energies of TBICz and TOXDCz ensure efficient energy transfer from the host to the phosphor and triplet exciton confinement on the phosphor.Solution-processable green phospho⁃rescent devices employing Ir(ppy)3 as guest and the two tetrasubstituted carbazole derivatives as hosts exhibit high ef⁃ficiencies.The best EL performance is achieved for the TBICz-based device,with a maximum current efficiency of 27.3 cd/A,a maximum power efficiency of 15.9 lm/W,and a maximum external quantum efficiency of 7.8%,which provides more host material options for solution-processed OLEDs.
基金Project(51578511)supported by the National Natural Science Foundation of China。
文摘To further investigate the one-dimensional(1D)rheological consolidation mechanism of double-layered soil,the fractional derivative Merchant model(FDMM)and the non-Darcian flow model with the non-Newtonian index are respectively introduced to describe the deformation of viscoelastic soil and the flow of pore water in the process of consolidation.Accordingly,an 1D rheological consolidation equation of double-layered soil is obtained,and its numerical analysis is performed by the implicit finite difference method.In order to verify its validity,the numerical solutions by the present method for some simplified cases are compared with the results in the related literature.Then,the influence of the revelent parameters on the rheological consolidation of double-layered soil are investigated.Numerical results indicate that the parameters of non-Darcian flow and FDMM of the first soil layer greatly influence the consolidation rate of double-layered soil.As the decrease of relative compressibility or the increase of relative permeability between the lower soil and the upper soil,the dissipation rate of excess pore water pressure and the settlement rate of the ground will be accelerated.Increasing the relative thickness of soil layer with high permeability or low compressibility will also accelerate the consolidation rate of double-layered soil.
基金supported by the National Natural Science Foundation of China (51479151,61403288)。
文摘Most of the existing multivariable grey models are based on the 1-order derivative and 1-order accumulation, which makes the parameters unable to be adjusted according to the data characteristics of the actual problems. The results about fractional derivative multivariable grey models are very few at present. In this paper, a multivariable Caputo fractional derivative grey model with convolution integral CFGMC(q, N) is proposed. First, the Caputo fractional difference is used to discretize the model, and the least square method is used to solve the parameters. The orders of accumulations and differential equations are determined by using particle swarm optimization(PSO). Then, the analytical solution of the model is obtained by using the Laplace transform, and the convergence and divergence of series in analytical solutions are also discussed. Finally, the CFGMC(q, N) model is used to predict the municipal solid waste(MSW). Compared with other competition models, the model has the best prediction effect. This study enriches the model form of the multivariable grey model, expands the scope of application, and provides a new idea for the development of fractional derivative grey model.
基金The project supported by National Natural Science Foundation of China(81403139)Research Committee of the University of Macao(MYRG2015-00161-ICMS-QRCM)
文摘OBJECTIVE To identify the specific targets of a novel derivative of Danshensu ADTM as the protein disulfide isomerase(PDI)family proteins including ERp57.To further investigate the underlying mechanism of ADTM to modulate ERp57 to regulate platelet function with direct interaction withαⅡbβ3 integrin.METHODS To isolate the protein targets that bound to ADTM,a biotin-conjugated ADTM analogue(BAA)was designed and synthesized.BAA(300μmol·L-1)was incubated with rat blood platelet lysates and the BAA-protein complexes were pulled down with NeutrAvidin-agarose followed by protein profiling using LC-MS/MS.To determine platelet aggregation in vitro,rabbit platelets were incubated with the indicated concentrations of compounds and aggregation was induced by ADP(10μmol·L-1)or AA(200μmol·L-1)and measured using a platelet aggregometer.To determine platelet aggregation-induced by ADP in rat in vivo,ADTM(5-20mg·kg-1)in comparison with DSS(10mg·kg-1)and clopidogrel(18mg·kg-1)were administered daily by i.v.injection for 5d,respectively.To determine the action of ADTM on the ERp57/αⅡbβ3 interaction,it was examined by immunoprecipitation with anti-αⅡbβ3antibody,followed by detection of ERp57 immunoreactivity using immunoblotting.RESULTS BAA could bind to various proteins involved in platelet function.In particular,platelet aggregation-associated proteins were identified with>95% protein identification probability including ERp72,ERp57ERp5 and PDI,which are members of the protein disulfide isomerase(PDI)family related to platelet function and redox homeostasis.ADTM exhibited potent inhibition on the redox activity of ERp57 in a concentration-dependent manner(IC50=100 300μmol·L-1).In in vitro studies,ADTM exhibited concentration-dependent inhibition on ADP-induced and AA-induced platelet aggregation with comparable effects to aspirin and clopidogrel.In vivo study showed that ADP-induced platelet aggregation was significantly compromised(>40%reduction)in rats treated with ADTM(20mg·kg-1).Similarly,ADTM also exhibited significant anti-thrombotic effect in vivo as shown in the ferric chloride(FeCl3)-induced venous thrombosis.Immunoprecipitation with anti-αⅡbβ3antibody,followed by detection of ERp57 immunoreactivity using immunoblotting showed that ADTM disrupted the interaction of ERp57 with αⅡ bβ3.CONCLUSION These results demonstrated that ADTM exhibited broad-spectrum anti-platelet activities and ERp57 is a potential therapeutic target for anti-platelet therapy.
基金support of National Natural Science Foundation of China (Grant No. 11672236)Project funded by China Postdoctoral Science Foundation (Grant No. 2018M641381)。
文摘Accurately evaluating the aerodynamic performance of a battle-structure-damaged aircraft is essential to enable the pilot to optimize the flight control strategy. Based on CFD and rigid dynamic mesh techniques,a numerical method is developed to calculate the longitudinal and longitudinal-lateral coupling forces and moments with small amplitude sinusoidal pitch oscillation, and the corresponding dynamic derivatives of two fragment-structure-damaged and two continuous-rod-damaged models modified from the SACCON UAV. The results indicate that, at the reference point set in this paper, additional positive damping is generated in fragment-damaged configurations;thus, the absolute values of the negative pitch dynamic derivative increase. The missing wingtip induces negative pitch damping on the aircraft and decreases the value of the pitch dynamic derivative. The missing middle wing causes a noticeable increase in the absolute value of the pitch dynamic derivative;the missing parts on the right wing cause the aircraft to roll to the right side in the dynamic process, and the pitch-roll coupling cross dynamic derivatives are positive. Moreover, the values of these derivatives increase as the damaged area on the right wing increases, and an optimal case with the smallest cross dynamic derivative can be found to help improve the survivability of damaged aircraft.
基金Project(20761002) supported by the National Natural Science Foundation of China
文摘Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and characterized by infrared spectrometry, 1H nuclear magnetic resonance, elemental analysis and gas chromatograph-mass spectrometry. The ligand synthetic route was optimized. The fluorescence properties of the complex in solid state, in different kind of solvents and in solutions with different pH values were investigated in detail. The results show that the yields of DSPDA and 4-SPDA reach over 78% by Wittig-Horner reaction and other eight pyridine-2, 6-dicarboxylic acid derivatives with different substituents on pyridine ring, and their complexes with Tb(Ⅲ) are also obtained. The fluorescence intensities of the complexes with electron-donating groups are more intense than those of the complexes with electron-withdrawing groups on pyridine ring; fluorescence intensities of the complexes are the strongest in neutral solution (pH=7), and the less the dipole moment of solvent molecule is, the stronger the fluorescence intensity is. It is found that the two ligands (4-APDA and DSPDA) are the good sensitizers for Tb(Ⅲ) ion.
文摘Reaction of Cp2TiCl2-Mg synthetic equivalent of practical Ti(II) reagent with propargyl alcohol derivatives affords allenyl titanium compounds in good yields.thus, providing an efficient and practical methods for synthesis of both allenyl and homopropargyl alcohols by the successive treatment with aldehydes and ketones.
文摘A new general optimal principle of designing explicit finite difference method was obtained. Several applied cases were put forward to explain the uses of the principle. The validity of the principal was tested by a numeric example.
文摘Nine 5 (β substituted stylryl) salicyladehyde derivatives were prepared by PTC Witting reactions in the paper . The stereochemistry of the Witting reactions and the substituted effect on the UV spectra of salicyladehyde derivaties have been reported . It was observed that the spectra undergo a red shift as the conjugative effect of substituted becomes stronger . A good linear relationship between the shift of UV of p substituted compounds and conjugation effect was obtained.It showed that the Hammett equation may be applied to the UV frequencies of the title compounds.
基金The project supported by Science and Technology Development Fund of Macao SAR(078/2011/A3)Research Committee of University of Macao〔MYRG138(Y1-Y4)-ICMS12-LMY〕
文摘OBJECTIVE To analyse structure and relationship of several andrographolide derivatives in multiple in vivo and in vitro angiogenesis assays,and to demonstrate a novel compound named AGL-2as a potential anti-angiogenesis agent.METHODS Human umbilical vein endothelial cells(HUVECs)in vitro and zebrafish(Danio rerio)in vivo models were used to screen and identify the anti-angiogenesis activities of six andrographolide derivatives;namely,AGL-1,AGL-2,AGS-72,AGS-72 a,AGS-79 and AGP-151.RESULTS AGL-2exhibited the strongest anti-angiogenic activity among all the derivatives in zebrafish model.Interestingly,another compound named AGS-72 showed stronger anti-angiogenic activity than AGL-2 in VEGF-induced HUVECs proliferation,migration,invasion and tube formation assays.In addition,AGL-2 was found to suppress the VEGF-induced VEGFR-2auto-phosphorylation and inhibit the activity of VEGFR-2 mediated signaling cascades in a dose-dependent manner.CONCLUSION AGL-2was demonstrated to be a promising anti-angiogenic agent among all the tested derivatives.The mechanism underlying the anti-angiogenic activity of AGL-2 probably involve VEGFR-2 signaling pathway.Even though,how some of chemical structure alterations result in discrepancy between in vivo and in vitro activities still remains to be resolved,this study shall provide new insight into how modification of the chemical structure of andrographolide affects this newly identified anti-angiogenesis activity.Meanwhile,AGL-2 can be exploited as a potential therapeutic agent for the treatment of angiogenesis-related diseases.
文摘It’s known to all that under ideal condition the s to rage cost is kept in lower level when storage management be arranged by Economic Order Quantity(EOQ).Does this mean that any companies should set up their own storing system in proportion to the scale of the commodities’ producing or sell ing Furthermore, even if they manage storage in EOQ, because of different oper ation scale, geographical condition or ability borrowing money from financial ma rket, different companies pay unequal cost in storing the same commodity.In thi s paper, except for supplying commodities from our own storage system, the autho rs have analyzed other two supplying ways without whole storage system, they are forward contracts and futures contracts.The authors have discussed variable su pply cost for above different supply measures.According to the cost of each sup ply way, the managers can choose the most economical way in supplying the commod ity and predict the price of futures from storage management arranged by EOQ.Th e summary content is as follow: 1. The comparing of supply cost between forward contracts and storing system a rranged by EOQ. (1) The supply cost from forward contracts (2) The supply cost from storage system arranged by Economic Order Quantity (3) The application example for comparing cost in different supply way 2.The comparing of supply cost between futures going physical and storing syst em arranged by Economic Order Quantity. (1) The supply cost from futures going physical (2) The correlation between futures contracts and storage management arranged b y EOQ (3) The application example for comparing cost in different supply way 3.How does storing system of scale economic affect the price of forward and fu tures contracts (1) How does the price of forward and futures contracts fluctuate (2) How do we calculate the price of a commodity at future point from the cost of scale economic storing (3) How do we operate efficiently in derivatives market by using the cost of sc ale economic storing (4) The application example for analyzing the price of futures 4.The correlation among storage managementforward contracts and futures mark et.
基金Ministry of Education and Science of the Russian Federation(14.613.21.0043)
文摘Six furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants have been investigated.It was shown that the use of some furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants can considerably increase ballistic parameters compared with HMX if the compounds under consideration contain difluoramine groups.And the use of the compounds under consideration may be successful only in the presence of an active binder and 10%-30% of AP or ADN as additional oxidizers.
文摘This study presents the synthesis of three dinuclear cobalt complexes based on three imine derivatives:bis-[4-(2-pyridylmethyleneamino)-phenyl]thioether(L1),bis-[4-(2-pyridylmethyleneamino)-phenyl]ether(L2),and bis-[4-(2-pyridylmethyleneamino)-phenyl]methane(L3).Single-crystal X-ray diffraction analysis reveals that the complexes[Co_(2)(L1)3](ClO_(4))4·2CH_(3)CN(1),[Co_(2)(L2)3](ClO_(4))4·2CH_(3)OH(2),and[Co_(2)(L3)3](ClO_(4))4·2CH_(3)OH(3)all exhibit a dinuclear structure.Magnetic test results show that complex 3 exhibited irreversible SCO behavior induced by loss of solvent at 300 K,with the average Co-N bond length increasing from 0.2139(3)to 0.2153(3)nm.Meanwhile,the desolvated complex 3 exhibited paramagnetic behavior similar to that of complexes 1 and 2.Variable-temperature UV-Vis spectroscopic studies also indicate that complex 3 undergoes a solvent-loss-induced spin-state transition.CCDC:2347354,1(120 K);2347355,2(120 K);2347356,3(120 K);2347357,3(400 K).
基金The project supported by Central Public Scientific Research Institution Fundamental Project(2016CX09)by National Natural Science Foundation of China(81573645)
文摘OBJECTIVE Pulmonary artery hypertension(PAH)is a severe disease characterized by the mean pulmonary artery pressure exceeding 25 mm Hg at rest.PAH could induce right heart failure and has a very high mortality rate.At present,several kinds of drugs have been used in the treatment of PAH.However,most of these drugs aim to relax pulmonary arteries and do not inhibit the injury of vessels.In other words,the drugs available for PAH treatment do not improve the survival rate of PAH patients and cannot satisfy the needs in clinic.To discover and develop novel candidate compounds effective on the treatment of pulmonary artery injury and remodeling will be very important.Based on these background,the present study aimed to study the protective effect of two novel Rho-kinases(Rho-associated coiledcoil forming protein serine/threonine kinase,ROCK)inhibitors,DL0805 derivatives(DL0805-1and DL0805-2),on pulmonary arterial cells and further evaluate the underlying mechanisms and the possibility of DL0805 derivatives become therapeutic drugs for PAH.METHODS The primary cultured pulmonary arterial cells including human pulmonary artery endothelium cells(HPAECs)and human pulmonary artery smooth muscle cells(HPASMCs)were used in this study.HPAECs were injured under hypoxia environment(1%O2)and treated with or without DL0805 derivatives.After 48 h,the proliferation and oxidative stress were observed.CCK8 was used to detect cell viability.DCFH-DA was used as probe for reactive oxygen species(ROS)under fluorescence imaging system.HPASMCs was stimulated by growth factors including platelet-derived growth factor-BB(PDGF-BB)and Fetal Bovine Serum(FBS).The proliferation was observed in the cells treated with or without DL0805 derivatives.HPASMCs treated with or without DL0805 derivatives were further incubated with endothelin(ET-1),the proliferation and cytoskeleton remodeling of cells were detected by immunofluorescence assay.At last,Western blotting(WB)and immunofluorescence assay were employed to analysis the underlying mechanisms in the above experiments.RESULTS 10μmol·L-1DL0805-2 could inhibit the proliferation of HPAECs induced by hypoxia.Each concentration of DL0805-1 and DL0805-2attenuated the production of ROS in HPAECs.Results from WB indicated that DL0805 derivatives decreased the injury of HPAECs induced by hypoxia through the inhibition of the expression of Rho A and the activity of ROCK.On HPASMCs,DL0805 derivatives reduced the proliferation induced by PDGF-BB and FBS and inhibited cytoskeleton remodeling induced by ET-1.Immunofluorescence assay showed that DL0805 derivatives inhibited ROCK activity and down regulated the phosphorylation levels of ROCK substrates.CONCLUSION DL0805derivatives exhibited protective effect on pulmonary arterial cells including endothelium cells and smooth muscle cells.Among the above experiments,DL0805-2 showed stronger potency than DL0805-1.These two compounds might protect the cells through the inhibition of Rho A/ROCK pathway and they probably have the potential in the treatment of PAH and deserve further evaluation.
基金The project supported by grants from the Science and Technology Development Fund of Macao,China(014/2011/A1and 078/2011/A3)Research Committee,University of Macao〔MYRG138(Y1-Y4)-ICMS12-LMY〕
文摘OBJECTIVE To investigate the cardioprotective effect of novel danshensu derivatives against doxorubicin(Dox)cardiotoxicity and their synergistic anti-tumor effect with Dox on breast cancer cells.METHODS Two new Danshensu derivatives were synthesized by conjugation with tetramethylpyrizine and/or4-(3-thioxo-3 H-1,2-dithiol-4-yl)-benzoic acid and tested for protective effects against Dox induced cardiotoxicity in cell and zebrafish.H9c2 cardiomyoblasts were co-treated with Dox and Danshensu derivatives for 24 h and then were measured for cell viability and cytotoxicity by MTT and LDH assays.The expression levels of mitochondrial biogenesis related proteins PGC-1α,NRF-1and Nrf2 were detected by Western blotting and qPCR.Moreover,in a Dox-induced cardiotoxicity model of zebrafish,zebrafish embryos were treated with Dox for 36 h,followed by measurement of numerous ventricular function parameters including heart rate,stroke volume,cardiac output and fractional shortening.In addition,the synergistic anti-tumor effects of the Danshensu derivatives and Dox had been studied in MCF-7 breast cancer cells.The effects of the Danshensu derivatives on the cell death and metabolism of MCF-7 cells were measured using apoptosis assay and Seahorse Metabolic Analyzers respectively.RESULTS Our results showed that the Danshensu derivatives were more potent than the parental compounds in ameliorating Dox-induced cytotoxicity in H9c2 cells and significantly preserving stroke volume of heart function in Dox-treated zebrafish.Further mechanistic studies identified that the danshensu derivatives increased mitochondrial copy numbers and protein expressions of PGC-1α,NRF-1 and Nrf2 in H9c2 cells.In addition,the Danshensu derivatives enhanced Dox-induced apoptosis,and decreased glycolysis and mitochondrial function in MCF-7 tumor cells.CONCLUSION Our results revealed that two new Danshensu derivatives displayed promising cardioprotective effects against Dox induced cardiotoxicity both in vivo and in vitro,at least partially through activating mitochondrial biogenesis.Also,the new Danshensu derivatives potentiated the anticancer effects of Dox in breast tumor cells involving induction of glycolytic inhibition and mitochondrial dysfunction.
