The amorphous boron powders with high activity were prepared by the high-energy ball milling-combustion synthesis method. The effects of the milling rate and milling time on the crystallinity, microscopic morphology a...The amorphous boron powders with high activity were prepared by the high-energy ball milling-combustion synthesis method. The effects of the milling rate and milling time on the crystallinity, microscopic morphology and reactivity of amorphous boron powder were studied. The results show that the crystallinity of amorphous nano-boron powder is only 22.5%, and its purity reaches 92.86%. The high-energy ball milling can significantly refine boron powder particle sizes, whose average particle sizes are smaller than 50 nm, and specific surface areas are of up to 70.03 m2/g. When the transmission electron beam irradiates the samples, they rapidly melt. It can be seen that the monomer amorphous boron size is less than 30 nm from the specimen melting traces, which indicates that the samples have high reactivity.展开更多
By varying concentration of PEG1000 as a structure-directing agent,mesoporous alumina with excellent textural properties was synthesized.The prepared mesoporous alumina displays high thermal stability,as shown by its ...By varying concentration of PEG1000 as a structure-directing agent,mesoporous alumina with excellent textural properties was synthesized.The prepared mesoporous alumina displays high thermal stability,as shown by its textural properties at different calcination temperatures of 600-850 °C.Characterization by SEM and TEM revealed that the added PEG surfactant induced the formation of petal-like alumina.XRD results clarified that all samples were amorphous and their peaks were around the peaks of γ-alumina.N_2 adsorption-desorption analysis showed that the prepared mesoporous alumina,if with PEG1000 in hydrolysis of aluminum isopropoxide,had excellent textural properties with large specific surface area,high pore volume and suitable pore size.The petal-like structure existing in the alumina samples improved their textural parameters,and the role and influential mechanism of PEG1000 were analyzed.展开更多
High temperature plastic deformation behavior of non-orientated electrical steel was investigated by Gleeble 1500 thermo-mechanical simulator at strain rate of 0.01-10 s^-1 and high temperature of 500-1 200 ℃. The st...High temperature plastic deformation behavior of non-orientated electrical steel was investigated by Gleeble 1500 thermo-mechanical simulator at strain rate of 0.01-10 s^-1 and high temperature of 500-1 200 ℃. The stress level factor (a), stress exponent (n), structural factor (A) and activation energy (Q) of high temperature plastic deformation process of non-orientated electrical steel in different temperature ranges were calculated by the Arrhenius model. The results show that, with dynamic elevation of deformation temperature, phase transformation from α-Fe to γ-Fe takes place simultaneously during plastic deformation, dynamic recovery and dynamic recrystallization process, leading to an irregular change of the steady flow stress. For high temperature plastic deformation between 500 and 800 ℃, the calculated values of a, n, A, and Q are 0.039 0 MPa 1, 7.93, 1.9× 10^18 s^-1, and 334.8 kJ/mol, respectively, and for high temperature plastic deformation between 1 050 and 1 200 ℃, the calculated values of a, n, A, and Q are 0.125 8 MPa1, 5.29, 1.0 × 10^28 s^-1, and 769.9 kJ/mol, respectively.展开更多
According to the structure features of Fe80P20, A series of clusters Fe4P were designed and focused on studying the stability of local structure, charge distribution and chemical bond, Using the DFT method, energy and...According to the structure features of Fe80P20, A series of clusters Fe4P were designed and focused on studying the stability of local structure, charge distribution and chemical bond, Using the DFT method, energy and structure of Fe4P clusters were optimized and analyzed. The computational results showed that the energy of cluster 1(2) has the lowest energy, and the possibility of its existence in the Fe80P20 is high. Analyzing the transition states among the clusters, it was found that the clusters in the doublet state are more stable than those in the quartet state. The numbers of the Fe-P bond in the clusters play important roles in the cluster stability and electrons transfer properties, The more numbers of Fe-P bonds in the clusters, the higher the cluster stability, and the weaker the ability of P atom to get electron, The number of Fe atoms, which has bonding interactions with the P atom, is direct proportional to the average 3d orbit population of Fe atom. Basing on the orbital population, average magnetic moments of each Fe atom in the Fe4P clusters were calculated, and they are all smaller than that of single metal Fe atom. This suggests that all Fe4P clusters have soft magnetic property and they are expected to be perfect material for preparing soft magnetic apparatus.展开更多
In order to improve the electrochemical hydrogen storage performance of the Mg2Ni-type electrode alloys, Mg in the alloy was partially substituted by La, and the nanocrystalline and amorphous Mg2Ni-type Mg20-xLaxNi10 ...In order to improve the electrochemical hydrogen storage performance of the Mg2Ni-type electrode alloys, Mg in the alloy was partially substituted by La, and the nanocrystalline and amorphous Mg2Ni-type Mg20-xLaxNi10 (x-=0, 2) alloys were synthesized by melt-spinning technique. The microstructures of the as-spun alloys were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical hydrogen storage properties of the experimental alloys were tested. The results show that no amorphous phase is detected in the as-spun Mg20Ni10 alloy, but the as-spun Mg18La2Ni10 alloy holds a major amorphous phase. As La content increases from 0 to 2, the maximum discharge capacity of the as-spun (20 m/s) alloys rises from 96.5 to 387.1 mA.h/g, and the capacity retaining rate (S20) at the 20th cycle grows from 31.3% to 71.7%. Melt-spinning engenders an impactful effect on the electrochemical hydrogen storage performances of the alloys. With the increase in the spinning rate from 0 to 30 m/s, the maximum discharge capacity increases from 30.3 to 135.5 mA.h/g for the Mg20Ni10 alloy, and from 197.2 to 406.5 mA-h/g for the Mg18La2Ni10 alloy. The capacity retaining rate (S20) of the Mg2oNi10 alloy at the 20th cycle slightly falls from 36.7% to 27.1%, but it markedly mounts up from 37.3% to 78.3% for the Mg18La2Ni10 alloy.展开更多
In times of global changes and turbulence like ours, more than anything, firms need some pillars of stability. By this paper we would like to develop a comprehensive and adaptive managerial approach of corporate reput...In times of global changes and turbulence like ours, more than anything, firms need some pillars of stability. By this paper we would like to develop a comprehensive and adaptive managerial approach of corporate reputation. This is based on the premise that intangible assets (in general) and corporate reputation (in particular) are more and more recognized and managed as sources of (unique) sustainable competitive advantages and as core determinants of firm competitiveness, which are relatively hard to build and very easy to loose.展开更多
Smart nanoparticles that respond to pathophysiological parameters,such as p H,GSH,and H2O2,have been developed with the huge and urgent demand for the high-efficient drug delivery systems(DDS)for cancer therapy.Herein...Smart nanoparticles that respond to pathophysiological parameters,such as p H,GSH,and H2O2,have been developed with the huge and urgent demand for the high-efficient drug delivery systems(DDS)for cancer therapy.Herein,cubic poly(ethylene glycol)(PEG)-modified mesoporous amorphous iron oxide(AFe)nanoparticles(AFe-PEG)have been successfully prepared as p H-stimulated drug carriers,which can combine doxorubicin(DOX)with a high loading capacity of 948 mg/g,forming a novel multifunctional AFe-PEG/DOX nanoparticulate DDS.In an acidic microenvironment,the AFe-PEG/DOX nanoparticles will not only release DOX efficiently,but also release Fe ions to catalyze the transformation of H2O2 to·OH,acting as fenton reagents.In vitro experimental results proved that the AFe-PEG/DOX nanoparticles can achieve combination of chemotherapeutic(CTT)and chemodynamic therapeutic(CDT)effects on Hela tumor cells.Furthermore,the intrinsic magnetism of AFePEG/DOX makes its cellular internalization efficiency be improved under an external magnetic field.Therefore,this work develops a new and promising magnetically targeted delivery and dual CTT/CDT therapeutic nano-medicine platform based on amorphous iron oxide.展开更多
In this paper, the determinants of the voluntary disclosure level of firms have been investigated during a period of deep financial crisis. Two disclosure indexes used as dependent variables are proposed: a global in...In this paper, the determinants of the voluntary disclosure level of firms have been investigated during a period of deep financial crisis. Two disclosure indexes used as dependent variables are proposed: a global index based on both quantitative and qualitative disclosure and a solely quantitative voluntary index. Firstly, the explanatory variables have been selected taking into account the main contributions of international literature. In addition, some specific variables have been introduced in order to take into account the peculiarities of Italian market system and the ongoing financial crisis. A positive relationship has been found among the global voluntary disclosure (GVD) and the number of employees, the dividend policy, and the presence of independent directors on the board. On the contrary, a negative correlation with respect to the percentage of the firm's outstanding shares held by directors (not independent) exists. With reference to the quantitative voluntary disclosure (QVD) index, there is a positive correlation with the number of employees, the dividend policy, the market floating, and the incidence of intangible assets. Moreover, such (quantitative) a disclosure is different depending on the industrial membership sector.展开更多
Experiments were carried to determine correlations of important fruit and plant characteristics using 30 fig genotypes. The correlation coefficients between these traits were calculated using SAS program. Fruit weight...Experiments were carried to determine correlations of important fruit and plant characteristics using 30 fig genotypes. The correlation coefficients between these traits were calculated using SAS program. Fruit weight, fruit diameter, fruit length, neck length, ostiolium width, abscission of the stalk from the twig, ease of peeling, fruit skin cracks, thickness of the fruit skin, texture of skin, fruit ribs, fruit internal cavity, TSS (total soluble solids), pH, acidity, TSS/acidity, trunk diameter, shoot length, yield per tree were traits examined in the study. According to five-year data, fruit weight was found to have positive correlation by fruit diameter (r = 0.92; P 〈 0.01), fruit length (r = 0.81; P 〈 0.01), neck length (r = 0.35; P 〈 0.01), ostiolium width (r = 0.23; P 〈 0.01), trunk diameter (r = 0.26; P 〈 0.01), fruit skin cracks (r = 0.26; P 〈 0.01) and negative correlation by TSS (r = -0.26; P 〈 0.01) and fruit ribs (r = -0.21; P 〈 0.01). Relations between some traits such as ostiolium width, abscission of the stalk from the twig, ease of peeling, fruit skin cracks, texture of skin and fruit ribs are deviated based on the years. Some relationships between fig fruit characteristics exist, which may help researchers to solve some problems such as ostiolium width and fruit skin cracking. These studies may contribute to producing fruit with a good quality and help to evaluate new cultivars.展开更多
In this series of 65 cases of aplastic anemia, 26 cases were treated by the kidney-tonifying and mediating method, 19 cases by western drugs, and the remaining 20 cases only by tonifying the kidney as controls. The re...In this series of 65 cases of aplastic anemia, 26 cases were treated by the kidney-tonifying and mediating method, 19 cases by western drugs, and the remaining 20 cases only by tonifying the kidney as controls. The results showed that the kidney-tonifying and mediating method was significantly superior in the total effective rate to the method of western drugs and that of tonifying the kidney alone (P展开更多
The paper is devoted to formulations of decay and mapped elastodynamic infinite elements, based on modified Bessel shape functions. These elements are appropriate for Soil-Structure Interaction (SSI) problems, solve...The paper is devoted to formulations of decay and mapped elastodynamic infinite elements, based on modified Bessel shape functions. These elements are appropriate for Soil-Structure Interaction (SSI) problems, solved in time or frequency domain and can be treated as a new form of the recently proposed Elastodynamic Infinite Elements with United Shape Functions (EIEUSF) infinite elements. The formulation of 2D Horizontal type Infinite Elements (HIE) is demonstrated here, but by similar techniques 2D Vertical (VIE) and 2D Comer (CIE) Infinite Elements can also be formulated. Using elastodynamic infinite elements is the easier and appropriate way to achieve an adequate simulation including basic aspects of Soil-Structure Interaction. Continuity along the artificial boundary (the line between finite and infinite elements) is discussed as well and the application of the proposed elastodynamic infinite elements in the Finite Element Method (FEM) is explained in brief. Finally, a numerical example shows the computational efficiency of the proposed infinite elements.展开更多
The physicochemical analysis was carried out to quantify the total soluble solids, acidity, pH, ascorbic acid contents and pulp colour of eight selected durian hybrid clones. The aim of this study was to select the mo...The physicochemical analysis was carried out to quantify the total soluble solids, acidity, pH, ascorbic acid contents and pulp colour of eight selected durian hybrid clones. The aim of this study was to select the most promising durian hybrids for commercialization. The durian hybrid fruits were collected in an established durian research plot. All tested characteristics with the exception for total soluble solids (TSS) showed significant differences (P 〈 0.05) amongst the eight durian hybrids with four check cultivars. F1 hybrid 15-3 had significantly higher pH (7.25) and lower titratable acidity (0.09%) than other hybrids. While for ascorbic acid content, durian hybrid 7-3 (26.13 rag/100 g) showed significantly higher than other hybrids. As for pulp colour, hybrids 1-15, 1-17 and 7-20 were yellowish orange/deep yellow. Even though there was no significant differences for TSS, three durian hybrids showed value above 39.00 °Brix and there were hybrid 14-3 (39.97 °Brix), hybrid 8-16 (39.83 °Brix) and hybrid 7-3 (39.50 °Brix). Based on the results of this study, Fl hybrids durian 1-15, 7-3, 8-16, 14-3 and 15-3 shall become successful candidates for recommendation to farmers for commercial production in Malaysia. However, further evaluations on fruit eating quality and stability of the hybrids should be completed prior to recommendation for commercialization.展开更多
The content of cytochrome oxidase (CCO), succinate dehydrogenase (SDH) and neutrophil alkaline phosphatase (NAP) in bone marrow cells in 68 cases of aplastic anemia before and after treatment was determined by com... The content of cytochrome oxidase (CCO), succinate dehydrogenase (SDH) and neutrophil alkaline phosphatase (NAP) in bone marrow cells in 68 cases of aplastic anemia before and after treatment was determined by computerized graphical analysis and compared with that of normal volunteers (control group). The significantly lowered CCO and SDH levels and the markedly increased NAP content before treatment (P<0.01) became approximately normal after that of supplementing the kidney and removing blood stasis (P >0.05).展开更多
The synthesis of large area, homogenous, single layer graphene on cobalt (Co) and nickel (Ni) is reported. The process involves vacuum annealing of sputtered amorphous carbon (a-C) deposited on Co/sapphire or Ni...The synthesis of large area, homogenous, single layer graphene on cobalt (Co) and nickel (Ni) is reported. The process involves vacuum annealing of sputtered amorphous carbon (a-C) deposited on Co/sapphire or Ni/sapphire substrates. The improved crystallinity of the metal film, assisted by the sapphire substrate, proves to be the key to the quality of as-grown graphene film. The crystallinity of the Co and Ni metal films was improved by sputtering the metal at elevated temperature as was verified by X-ray diffraction (XRD). After sputtering of a-C and annealing, large area, single layer graphene that occupies almost the entire area of the substrate was produced. With this method, 100 mm2-area single layer graphene can be synthesized and is limited only by the substrate and vacuum chamber size. The homogeneity of the graphene film is not dependent on the cooling rate, in contrast to syntheses using polycrystalline metal films and conventional chemical vapor deposition (CVD) growth. Our facile method of producing single layer graphene on Co and Ni metal films should lead to large scale graphene-based applications.展开更多
A series of the amorphous Gd75-55A125-5Fe0-40 alloy ribbons were prepared by melt spinning. The structure, magnetic properties and magnetocaloric effect (MCE) of these alloys were investigated. The prepared samples ...A series of the amorphous Gd75-55A125-5Fe0-40 alloy ribbons were prepared by melt spinning. The structure, magnetic properties and magnetocaloric effect (MCE) of these alloys were investigated. The prepared samples have shown the characteristics of a second-order phase transition with zero hysteresis loss and the Tc can be tuned by changing the Fe contents. For the different compositions, the magnetic entropy change (-△Sm) for a field change of 0-5 T reached a maximum value of 7.14 J kg 1 K1 in the Gd70A120Fel0 alloy near its Curie temperature (To) of 149 K. The non-linear composition dependence of (- △ Sin) could be caused by the competitions between Fe-Fe, Fe-Gd and Gd-Gd interactions. The refrigeration capacity (RC) values of these al- loys are about 532-780 J/kg under a magnetic field change of 0-5 T. The results indicate that amorphous GdFeA1 alloys can be considered as ideal candidates for a magnetic refrigerant in the temperature range of 104-222 K.展开更多
The magnetic properties and magnetocaloric effects of amorphous and crystalline Gd55Co35Ni10 ribbons are investigated.A main phase with a Ho 12 Co 7-type monoclinic structure(space group P21/c) and a minor phase with ...The magnetic properties and magnetocaloric effects of amorphous and crystalline Gd55Co35Ni10 ribbons are investigated.A main phase with a Ho 12 Co 7-type monoclinic structure(space group P21/c) and a minor phase with a Ho4Co3-type hexagonal structure(space group P63/m) are obtained for crystalline ribbon after annealing.The amorphous ribbons order ferromagnetically and undergo a second-order transition at 192 K.For crystalline Gd55Co35Ni10 ribbons,two magnetic phase transitions occur at 158 and 214 K,respectively.The peak value of-△SM under a field change of 0-5 T is 6.5 J/kg K at 192 K for amorphous Gd55Co35Ni10 ribbons.A relatively large magnetic entropy change(~5.0 J/kg K) under a field change of 0-5 T for the crystalline Gd55Co35Ni10 ribbons is obtained in the temperature interval range of 154-214 K.The large platform of magnetic entropy change and the negligible thermal/magnetic hysteresis loss mean the crystalline Gd55Co35Ni10 compound can satisfy the requirement of the Ericsson-type refrigerator working in the temperature range from 154K to 214K.展开更多
3’,4’-Dimethoxy-flavonol-3-O-β-D-glucopyranoside monohydrate(GDH),which can significantly reduce blood lipids,atherosclerotic aortic lesions,and liver injury,has poor oral bioavailability.In the present study,we ai...3’,4’-Dimethoxy-flavonol-3-O-β-D-glucopyranoside monohydrate(GDH),which can significantly reduce blood lipids,atherosclerotic aortic lesions,and liver injury,has poor oral bioavailability.In the present study,we aimed to prepare and characterize five new polymorphs of GDH(II,III,IV,V,and VI)and the amorphous form of GDH(GDH-AM).The GDH polymorphs and GDH-AM were characterized by scanning electron microscopy(SEM),differential scanning calorimetry(DSC),thermogravimetric analysis(TGA),X-ray powder diffraction(XRPD),and Fourier transform infrared spectroscopy(FTIR).Dissolution tests,physical stability,polymorphic transformation,and permeability studies were subsequently investigated.Dissolution of GDH-II and GDH-IV reached higher concentrations compared with GDH-I.GDH-AM exhibited a significantly high dissolution rate and prolonged supersaturation during dissolution.No phase transition was found for GDH-I and GDH-AM after 3 months of storage,while GDH-II,GDH-III,GDH-IV,GDH-V,and GDH-VI were readily converted to GDH-I.In situ single-pass intestinal perfusion experiments showed that the high concentration of GDH exhibited low permeability.Sodium dodecyl sulfate and bovine bile salts were used as absorption enhancers to improve the permeability of GDH.The results showed that sodium dodecyl sulfate and taurocholate were good absorption enhancers for further formulation development of GDH.展开更多
Pseudocapacitors with high power density,longterm durability,as well as reliable safety,play a key role in energy conversion and storage.Designing electrode materials combing the features of high specific capacitance,...Pseudocapacitors with high power density,longterm durability,as well as reliable safety,play a key role in energy conversion and storage.Designing electrode materials combing the features of high specific capacitance,excellent rate performance,and outstanding mechanical stability is still a challenge.Herein,a facile partial sulfurization strategy has been developed to modulate the electronic structure and crystalline texture of cobalt hydroxide nanosheets(denoted as Co(OH)2)at room temperature.The resultant cobalt hydroxysulfide nanosheet(denoted as Co SOH)electrode with abundant low-valence cobalt species and amorphous structure,exhibits a high specific capacitance of 2110 F g^-1at1 A g^-1with an excellent capability retention rate of 92.1%at10 A g^-1,which is much larger than that of Co(OH)2 precursor(916 F g^-1at 1 A g^-1 and 80%retention at 10 A g^-1).Furthermore,the fabricated asymmetric supercapacitor device constructed with Co SOH and active carbon displays a considerable high energy density of 44.9 W h kg^-1at a power density of 400 W kg^-1,and exceptional stability after 8000cycles.展开更多
Photovoltaic performance of the organic solar cells (OSCs) based on 2-((5'-(4-((4-((E)-2-(5'-(2,2-dicyanovinyl)-3',4-dihexyl- 2,2'-bithiophen-5-yl)vinyl) phenyl)(phenyl)amino)styryl)-4~4'-dihe...Photovoltaic performance of the organic solar cells (OSCs) based on 2-((5'-(4-((4-((E)-2-(5'-(2,2-dicyanovinyl)-3',4-dihexyl- 2,2'-bithiophen-5-yl)vinyl) phenyl)(phenyl)amino)styryl)-4~4'-dihexyl-2,2'-bithiophen-5-yl)methylene)malononitrile (L(TPA- bTV-DCN)) as donor and PC70BM as acceptor was optimized using 0.25 vol% high boiling point solvent additive of 1-chloronaphthalene (CN), 1,6-hexanedithiol (HDT), or 1,8-diodooctane (DIO). The optimized OSC based on L(TPA-bTV- DCN)-PC70BM (1:2, w/w) with 0.25 vol% CN exhibits an enhanced power conversion efficiency (PCE) of 2.61%, with Voc of 0.87 V, Jsc of 6.95 mA/cm2, and FF of 43.2%, under the illumination of 100 mW/cm2 AM 1.5 G simulated solar light, whereas the PCE of the OSC based on the same active layer without additive is only 1.79%. The effect of the additive on absorption spectra and the atomic force microscopy images of L(TPA-bTV-DCN)-PCv0BM blend films were further investigated. The improved efficiency of the device could be ascribed to the enhanced absorption and optimized domain size in the L(TPA-bTV-DCN)-PC70BM blend film.展开更多
基金Project(51002025)supported by the National Natural Science Foundation of China
文摘The amorphous boron powders with high activity were prepared by the high-energy ball milling-combustion synthesis method. The effects of the milling rate and milling time on the crystallinity, microscopic morphology and reactivity of amorphous boron powder were studied. The results show that the crystallinity of amorphous nano-boron powder is only 22.5%, and its purity reaches 92.86%. The high-energy ball milling can significantly refine boron powder particle sizes, whose average particle sizes are smaller than 50 nm, and specific surface areas are of up to 70.03 m2/g. When the transmission electron beam irradiates the samples, they rapidly melt. It can be seen that the monomer amorphous boron size is less than 30 nm from the specimen melting traces, which indicates that the samples have high reactivity.
基金Supported by the National Basic Research Program of China(Y419012198)the National Natural Science Foundation of China(No.91534125)
文摘By varying concentration of PEG1000 as a structure-directing agent,mesoporous alumina with excellent textural properties was synthesized.The prepared mesoporous alumina displays high thermal stability,as shown by its textural properties at different calcination temperatures of 600-850 °C.Characterization by SEM and TEM revealed that the added PEG surfactant induced the formation of petal-like alumina.XRD results clarified that all samples were amorphous and their peaks were around the peaks of γ-alumina.N_2 adsorption-desorption analysis showed that the prepared mesoporous alumina,if with PEG1000 in hydrolysis of aluminum isopropoxide,had excellent textural properties with large specific surface area,high pore volume and suitable pore size.The petal-like structure existing in the alumina samples improved their textural parameters,and the role and influential mechanism of PEG1000 were analyzed.
基金Project(2005038560) supported by the Postdoctoral Foundation of ChinaProject(05GK1002-2) supported by Key Program of Hunan Province
文摘High temperature plastic deformation behavior of non-orientated electrical steel was investigated by Gleeble 1500 thermo-mechanical simulator at strain rate of 0.01-10 s^-1 and high temperature of 500-1 200 ℃. The stress level factor (a), stress exponent (n), structural factor (A) and activation energy (Q) of high temperature plastic deformation process of non-orientated electrical steel in different temperature ranges were calculated by the Arrhenius model. The results show that, with dynamic elevation of deformation temperature, phase transformation from α-Fe to γ-Fe takes place simultaneously during plastic deformation, dynamic recovery and dynamic recrystallization process, leading to an irregular change of the steady flow stress. For high temperature plastic deformation between 500 and 800 ℃, the calculated values of a, n, A, and Q are 0.039 0 MPa 1, 7.93, 1.9× 10^18 s^-1, and 334.8 kJ/mol, respectively, and for high temperature plastic deformation between 1 050 and 1 200 ℃, the calculated values of a, n, A, and Q are 0.125 8 MPa1, 5.29, 1.0 × 10^28 s^-1, and 769.9 kJ/mol, respectively.
文摘According to the structure features of Fe80P20, A series of clusters Fe4P were designed and focused on studying the stability of local structure, charge distribution and chemical bond, Using the DFT method, energy and structure of Fe4P clusters were optimized and analyzed. The computational results showed that the energy of cluster 1(2) has the lowest energy, and the possibility of its existence in the Fe80P20 is high. Analyzing the transition states among the clusters, it was found that the clusters in the doublet state are more stable than those in the quartet state. The numbers of the Fe-P bond in the clusters play important roles in the cluster stability and electrons transfer properties, The more numbers of Fe-P bonds in the clusters, the higher the cluster stability, and the weaker the ability of P atom to get electron, The number of Fe atoms, which has bonding interactions with the P atom, is direct proportional to the average 3d orbit population of Fe atom. Basing on the orbital population, average magnetic moments of each Fe atom in the Fe4P clusters were calculated, and they are all smaller than that of single metal Fe atom. This suggests that all Fe4P clusters have soft magnetic property and they are expected to be perfect material for preparing soft magnetic apparatus.
基金Projects(50871050, 50961009) supported by the National Natural Science Foundation of ChinaProject(2010ZD05) supported by the Natural Science Foundation of Inner Mongolia, ChinaProject(NJzy08071) supported by the Higher Education Science Research Project of Inner Mongolia, China
文摘In order to improve the electrochemical hydrogen storage performance of the Mg2Ni-type electrode alloys, Mg in the alloy was partially substituted by La, and the nanocrystalline and amorphous Mg2Ni-type Mg20-xLaxNi10 (x-=0, 2) alloys were synthesized by melt-spinning technique. The microstructures of the as-spun alloys were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical hydrogen storage properties of the experimental alloys were tested. The results show that no amorphous phase is detected in the as-spun Mg20Ni10 alloy, but the as-spun Mg18La2Ni10 alloy holds a major amorphous phase. As La content increases from 0 to 2, the maximum discharge capacity of the as-spun (20 m/s) alloys rises from 96.5 to 387.1 mA.h/g, and the capacity retaining rate (S20) at the 20th cycle grows from 31.3% to 71.7%. Melt-spinning engenders an impactful effect on the electrochemical hydrogen storage performances of the alloys. With the increase in the spinning rate from 0 to 30 m/s, the maximum discharge capacity increases from 30.3 to 135.5 mA.h/g for the Mg20Ni10 alloy, and from 197.2 to 406.5 mA-h/g for the Mg18La2Ni10 alloy. The capacity retaining rate (S20) of the Mg2oNi10 alloy at the 20th cycle slightly falls from 36.7% to 27.1%, but it markedly mounts up from 37.3% to 78.3% for the Mg18La2Ni10 alloy.
文摘In times of global changes and turbulence like ours, more than anything, firms need some pillars of stability. By this paper we would like to develop a comprehensive and adaptive managerial approach of corporate reputation. This is based on the premise that intangible assets (in general) and corporate reputation (in particular) are more and more recognized and managed as sources of (unique) sustainable competitive advantages and as core determinants of firm competitiveness, which are relatively hard to build and very easy to loose.
基金supported by the National Natural Science Foundation of China(No.51473152 and No.51573174)Scientific Research Foundation for Young Talents from Fujian Provincial Department of Education(No.JT180494)Scientific Research Platform Construction Project from Fujian Provincial Department of Science and Technology(No.2018H2002)。
文摘Smart nanoparticles that respond to pathophysiological parameters,such as p H,GSH,and H2O2,have been developed with the huge and urgent demand for the high-efficient drug delivery systems(DDS)for cancer therapy.Herein,cubic poly(ethylene glycol)(PEG)-modified mesoporous amorphous iron oxide(AFe)nanoparticles(AFe-PEG)have been successfully prepared as p H-stimulated drug carriers,which can combine doxorubicin(DOX)with a high loading capacity of 948 mg/g,forming a novel multifunctional AFe-PEG/DOX nanoparticulate DDS.In an acidic microenvironment,the AFe-PEG/DOX nanoparticles will not only release DOX efficiently,but also release Fe ions to catalyze the transformation of H2O2 to·OH,acting as fenton reagents.In vitro experimental results proved that the AFe-PEG/DOX nanoparticles can achieve combination of chemotherapeutic(CTT)and chemodynamic therapeutic(CDT)effects on Hela tumor cells.Furthermore,the intrinsic magnetism of AFePEG/DOX makes its cellular internalization efficiency be improved under an external magnetic field.Therefore,this work develops a new and promising magnetically targeted delivery and dual CTT/CDT therapeutic nano-medicine platform based on amorphous iron oxide.
文摘In this paper, the determinants of the voluntary disclosure level of firms have been investigated during a period of deep financial crisis. Two disclosure indexes used as dependent variables are proposed: a global index based on both quantitative and qualitative disclosure and a solely quantitative voluntary index. Firstly, the explanatory variables have been selected taking into account the main contributions of international literature. In addition, some specific variables have been introduced in order to take into account the peculiarities of Italian market system and the ongoing financial crisis. A positive relationship has been found among the global voluntary disclosure (GVD) and the number of employees, the dividend policy, and the presence of independent directors on the board. On the contrary, a negative correlation with respect to the percentage of the firm's outstanding shares held by directors (not independent) exists. With reference to the quantitative voluntary disclosure (QVD) index, there is a positive correlation with the number of employees, the dividend policy, the market floating, and the incidence of intangible assets. Moreover, such (quantitative) a disclosure is different depending on the industrial membership sector.
文摘Experiments were carried to determine correlations of important fruit and plant characteristics using 30 fig genotypes. The correlation coefficients between these traits were calculated using SAS program. Fruit weight, fruit diameter, fruit length, neck length, ostiolium width, abscission of the stalk from the twig, ease of peeling, fruit skin cracks, thickness of the fruit skin, texture of skin, fruit ribs, fruit internal cavity, TSS (total soluble solids), pH, acidity, TSS/acidity, trunk diameter, shoot length, yield per tree were traits examined in the study. According to five-year data, fruit weight was found to have positive correlation by fruit diameter (r = 0.92; P 〈 0.01), fruit length (r = 0.81; P 〈 0.01), neck length (r = 0.35; P 〈 0.01), ostiolium width (r = 0.23; P 〈 0.01), trunk diameter (r = 0.26; P 〈 0.01), fruit skin cracks (r = 0.26; P 〈 0.01) and negative correlation by TSS (r = -0.26; P 〈 0.01) and fruit ribs (r = -0.21; P 〈 0.01). Relations between some traits such as ostiolium width, abscission of the stalk from the twig, ease of peeling, fruit skin cracks, texture of skin and fruit ribs are deviated based on the years. Some relationships between fig fruit characteristics exist, which may help researchers to solve some problems such as ostiolium width and fruit skin cracking. These studies may contribute to producing fruit with a good quality and help to evaluate new cultivars.
文摘In this series of 65 cases of aplastic anemia, 26 cases were treated by the kidney-tonifying and mediating method, 19 cases by western drugs, and the remaining 20 cases only by tonifying the kidney as controls. The results showed that the kidney-tonifying and mediating method was significantly superior in the total effective rate to the method of western drugs and that of tonifying the kidney alone (P
文摘The paper is devoted to formulations of decay and mapped elastodynamic infinite elements, based on modified Bessel shape functions. These elements are appropriate for Soil-Structure Interaction (SSI) problems, solved in time or frequency domain and can be treated as a new form of the recently proposed Elastodynamic Infinite Elements with United Shape Functions (EIEUSF) infinite elements. The formulation of 2D Horizontal type Infinite Elements (HIE) is demonstrated here, but by similar techniques 2D Vertical (VIE) and 2D Comer (CIE) Infinite Elements can also be formulated. Using elastodynamic infinite elements is the easier and appropriate way to achieve an adequate simulation including basic aspects of Soil-Structure Interaction. Continuity along the artificial boundary (the line between finite and infinite elements) is discussed as well and the application of the proposed elastodynamic infinite elements in the Finite Element Method (FEM) is explained in brief. Finally, a numerical example shows the computational efficiency of the proposed infinite elements.
文摘The physicochemical analysis was carried out to quantify the total soluble solids, acidity, pH, ascorbic acid contents and pulp colour of eight selected durian hybrid clones. The aim of this study was to select the most promising durian hybrids for commercialization. The durian hybrid fruits were collected in an established durian research plot. All tested characteristics with the exception for total soluble solids (TSS) showed significant differences (P 〈 0.05) amongst the eight durian hybrids with four check cultivars. F1 hybrid 15-3 had significantly higher pH (7.25) and lower titratable acidity (0.09%) than other hybrids. While for ascorbic acid content, durian hybrid 7-3 (26.13 rag/100 g) showed significantly higher than other hybrids. As for pulp colour, hybrids 1-15, 1-17 and 7-20 were yellowish orange/deep yellow. Even though there was no significant differences for TSS, three durian hybrids showed value above 39.00 °Brix and there were hybrid 14-3 (39.97 °Brix), hybrid 8-16 (39.83 °Brix) and hybrid 7-3 (39.50 °Brix). Based on the results of this study, Fl hybrids durian 1-15, 7-3, 8-16, 14-3 and 15-3 shall become successful candidates for recommendation to farmers for commercial production in Malaysia. However, further evaluations on fruit eating quality and stability of the hybrids should be completed prior to recommendation for commercialization.
文摘 The content of cytochrome oxidase (CCO), succinate dehydrogenase (SDH) and neutrophil alkaline phosphatase (NAP) in bone marrow cells in 68 cases of aplastic anemia before and after treatment was determined by computerized graphical analysis and compared with that of normal volunteers (control group). The significantly lowered CCO and SDH levels and the markedly increased NAP content before treatment (P<0.01) became approximately normal after that of supplementing the kidney and removing blood stasis (P >0.05).
文摘The synthesis of large area, homogenous, single layer graphene on cobalt (Co) and nickel (Ni) is reported. The process involves vacuum annealing of sputtered amorphous carbon (a-C) deposited on Co/sapphire or Ni/sapphire substrates. The improved crystallinity of the metal film, assisted by the sapphire substrate, proves to be the key to the quality of as-grown graphene film. The crystallinity of the Co and Ni metal films was improved by sputtering the metal at elevated temperature as was verified by X-ray diffraction (XRD). After sputtering of a-C and annealing, large area, single layer graphene that occupies almost the entire area of the substrate was produced. With this method, 100 mm2-area single layer graphene can be synthesized and is limited only by the substrate and vacuum chamber size. The homogeneity of the graphene film is not dependent on the cooling rate, in contrast to syntheses using polycrystalline metal films and conventional chemical vapor deposition (CVD) growth. Our facile method of producing single layer graphene on Co and Ni metal films should lead to large scale graphene-based applications.
基金supported by the Guangdong Provincial Science and Technology Program (Grant Nos. 2010B050300008, 2007B010600043)the Fundamental Research Funds for the Central Universities, South China University of Technology (Grant No. 2009ZM0291)
文摘A series of the amorphous Gd75-55A125-5Fe0-40 alloy ribbons were prepared by melt spinning. The structure, magnetic properties and magnetocaloric effect (MCE) of these alloys were investigated. The prepared samples have shown the characteristics of a second-order phase transition with zero hysteresis loss and the Tc can be tuned by changing the Fe contents. For the different compositions, the magnetic entropy change (-△Sm) for a field change of 0-5 T reached a maximum value of 7.14 J kg 1 K1 in the Gd70A120Fel0 alloy near its Curie temperature (To) of 149 K. The non-linear composition dependence of (- △ Sin) could be caused by the competitions between Fe-Fe, Fe-Gd and Gd-Gd interactions. The refrigeration capacity (RC) values of these al- loys are about 532-780 J/kg under a magnetic field change of 0-5 T. The results indicate that amorphous GdFeA1 alloys can be considered as ideal candidates for a magnetic refrigerant in the temperature range of 104-222 K.
基金supported by the Guangdong Provincial Science and Technology Program(Grant Nos.2010B050300008,2009B090300273 and 2007B010600043)the Guangzhou Municipal Science and Technology Program(Grant No.12F582080022)+1 种基金the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry (Grant No.x2clB7120290)the Fundamental Research Funds for the Central Universities(Grant Nos.2011ZM0014 and 2012ZZ0013)
文摘The magnetic properties and magnetocaloric effects of amorphous and crystalline Gd55Co35Ni10 ribbons are investigated.A main phase with a Ho 12 Co 7-type monoclinic structure(space group P21/c) and a minor phase with a Ho4Co3-type hexagonal structure(space group P63/m) are obtained for crystalline ribbon after annealing.The amorphous ribbons order ferromagnetically and undergo a second-order transition at 192 K.For crystalline Gd55Co35Ni10 ribbons,two magnetic phase transitions occur at 158 and 214 K,respectively.The peak value of-△SM under a field change of 0-5 T is 6.5 J/kg K at 192 K for amorphous Gd55Co35Ni10 ribbons.A relatively large magnetic entropy change(~5.0 J/kg K) under a field change of 0-5 T for the crystalline Gd55Co35Ni10 ribbons is obtained in the temperature interval range of 154-214 K.The large platform of magnetic entropy change and the negligible thermal/magnetic hysteresis loss mean the crystalline Gd55Co35Ni10 compound can satisfy the requirement of the Ericsson-type refrigerator working in the temperature range from 154K to 214K.
文摘3’,4’-Dimethoxy-flavonol-3-O-β-D-glucopyranoside monohydrate(GDH),which can significantly reduce blood lipids,atherosclerotic aortic lesions,and liver injury,has poor oral bioavailability.In the present study,we aimed to prepare and characterize five new polymorphs of GDH(II,III,IV,V,and VI)and the amorphous form of GDH(GDH-AM).The GDH polymorphs and GDH-AM were characterized by scanning electron microscopy(SEM),differential scanning calorimetry(DSC),thermogravimetric analysis(TGA),X-ray powder diffraction(XRPD),and Fourier transform infrared spectroscopy(FTIR).Dissolution tests,physical stability,polymorphic transformation,and permeability studies were subsequently investigated.Dissolution of GDH-II and GDH-IV reached higher concentrations compared with GDH-I.GDH-AM exhibited a significantly high dissolution rate and prolonged supersaturation during dissolution.No phase transition was found for GDH-I and GDH-AM after 3 months of storage,while GDH-II,GDH-III,GDH-IV,GDH-V,and GDH-VI were readily converted to GDH-I.In situ single-pass intestinal perfusion experiments showed that the high concentration of GDH exhibited low permeability.Sodium dodecyl sulfate and bovine bile salts were used as absorption enhancers to improve the permeability of GDH.The results showed that sodium dodecyl sulfate and taurocholate were good absorption enhancers for further formulation development of GDH.
基金surpported by the National Natural Science Foundation of China(21902108,21975163 and 51902204)China Postdoctoral Science Foundation(2019M663035)。
文摘Pseudocapacitors with high power density,longterm durability,as well as reliable safety,play a key role in energy conversion and storage.Designing electrode materials combing the features of high specific capacitance,excellent rate performance,and outstanding mechanical stability is still a challenge.Herein,a facile partial sulfurization strategy has been developed to modulate the electronic structure and crystalline texture of cobalt hydroxide nanosheets(denoted as Co(OH)2)at room temperature.The resultant cobalt hydroxysulfide nanosheet(denoted as Co SOH)electrode with abundant low-valence cobalt species and amorphous structure,exhibits a high specific capacitance of 2110 F g^-1at1 A g^-1with an excellent capability retention rate of 92.1%at10 A g^-1,which is much larger than that of Co(OH)2 precursor(916 F g^-1at 1 A g^-1 and 80%retention at 10 A g^-1).Furthermore,the fabricated asymmetric supercapacitor device constructed with Co SOH and active carbon displays a considerable high energy density of 44.9 W h kg^-1at a power density of 400 W kg^-1,and exceptional stability after 8000cycles.
基金supported by the National Basic Research Program of China(2014CB643501)the National Natural Science Foundation of China(91333204)the support from Ministry of Education and Jiangsu Province(20100092120037,XNY-48-037)
文摘Photovoltaic performance of the organic solar cells (OSCs) based on 2-((5'-(4-((4-((E)-2-(5'-(2,2-dicyanovinyl)-3',4-dihexyl- 2,2'-bithiophen-5-yl)vinyl) phenyl)(phenyl)amino)styryl)-4~4'-dihexyl-2,2'-bithiophen-5-yl)methylene)malononitrile (L(TPA- bTV-DCN)) as donor and PC70BM as acceptor was optimized using 0.25 vol% high boiling point solvent additive of 1-chloronaphthalene (CN), 1,6-hexanedithiol (HDT), or 1,8-diodooctane (DIO). The optimized OSC based on L(TPA-bTV- DCN)-PC70BM (1:2, w/w) with 0.25 vol% CN exhibits an enhanced power conversion efficiency (PCE) of 2.61%, with Voc of 0.87 V, Jsc of 6.95 mA/cm2, and FF of 43.2%, under the illumination of 100 mW/cm2 AM 1.5 G simulated solar light, whereas the PCE of the OSC based on the same active layer without additive is only 1.79%. The effect of the additive on absorption spectra and the atomic force microscopy images of L(TPA-bTV-DCN)-PCv0BM blend films were further investigated. The improved efficiency of the device could be ascribed to the enhanced absorption and optimized domain size in the L(TPA-bTV-DCN)-PC70BM blend film.