The ferromagnetic manganese doped TiN films were grown by plasma assisted molecular beam epitaxy on MgO(001) substrates. The nitrogen concentration and the ratio of manganese at Ti lattice sites increase after the p...The ferromagnetic manganese doped TiN films were grown by plasma assisted molecular beam epitaxy on MgO(001) substrates. The nitrogen concentration and the ratio of manganese at Ti lattice sites increase after the plasma annealing post treatment. TIN(002) peak shifts toward low angle direction and TiN(111) peak disappears after the post treatment. The lattice expansion and peak shift are mainly ascribed to the reduction of nitrogen vacancies in films. The magnetism was suppressed in as-prepared sample due to the pinning effect of the nitrogen vacancies at defect sites or interface. The magnetism can be activated by the plasma implantation along with nitrogen vacancies reduce. The decrease of nitrogen vacancies leads to the enhancement of ferromagnetism.展开更多
Focal nodular hyperplasia(FNH) of the liver is a benign lesion occurring in 0.6%-3% of the general population that probably reflects a local hyperplastic response of hepatocytes to a vascular abnormality. Most lesions...Focal nodular hyperplasia(FNH) of the liver is a benign lesion occurring in 0.6%-3% of the general population that probably reflects a local hyperplastic response of hepatocytes to a vascular abnormality. Most lesions are diagnosed incidentally and the natural history of the disease remains largely unknown. It has been shown that most FNH remain stable, or even regress, over a long follow-up period. We present a patient with FNH of the liver who was followed up for 7 years. A 26-yearold woman with a 5-year history of oral contraceptive use was referred to our hospital in February 2005 for further examination of a liver tumour. The diagnosis of FNH was made using magnetic resonance(MR) imaging with hepatospecific contrast media; this technique allows a correct diagnosis, in particular distinguishing FNH from hepatic adenoma, avoiding an invasive procedure such as the lesion biopsy. After 7-year from the diagnosis, we observed the complete spontaneous regression of the lesion by enhanced MR scanning. In this patient, discontinuation of oral contraceptive use and two childbirths may have influenced the natural history of FNH. To our knowledge, in the English literature there is no report illustrating a complete regression of giant FNH but only studies of decreasing in size. The present case suggests that a young patient with giant FNH should be managed conservatively rather than by resection, because FNH has the potential for spontaneous regression.展开更多
Objective To investigate the influence of vitamin D receptor (VDR) gene polymorphisms on susceptibility to type 1 diabetes mellitus (T1DM) in the Chinese Han population. Method One hundred and thirty-six Chinese ...Objective To investigate the influence of vitamin D receptor (VDR) gene polymorphisms on susceptibility to type 1 diabetes mellitus (T1DM) in the Chinese Han population. Method One hundred and thirty-six Chinese Han people, including 54 T1DM patients and 82 unrelated healthy subjects as control were genotyped by polymerase chain reaction-restriction fragment length polymorphism for three restriction sites in the VDR gene, which were ApaI, TaqI, and BamL Results The frequency of B allele of BsmI site in VDR gene was significantly higher in T1DM patients than in healthy subjects ( P = 0. 033 ) while no difference was found between the two groups in the distribution of ApaI and TaqI polymorphisms. Conclusion The BsmI polymorphism of VDR gene may be associated with the susceptibihty to T1DM in the Chinese Han population of Beijing.展开更多
After interface layer was simulated by the magnetic nano-particles in the egg white phantom, high intensity focused ultrasound (HIFU) at the same dosage was introduced to radiate the phantom in different depths to b...After interface layer was simulated by the magnetic nano-particles in the egg white phantom, high intensity focused ultrasound (HIFU) at the same dosage was introduced to radiate the phantom in different depths to blow the acoustic interface layer to mimic "point" exposure. The results showed that the volumes of biological focal region (BFR) were enlarged when the acoustic focal region (AFR) is close with interface layer. This meant that the magnetic nano-particles enhanced the therapeutic efficiency of HIFU. When the distance of the AFR from the interface layer was 10 mm, the size and shape of the BFR were similar with those of the control group, but a larger lesion at the interface, which was harmful for treatment, was observed. When the distance of the AFR to the interface layer increased to 30 mm, the size and shape of the BFR were also similar to those of the control group. When the thickness of the interface layer diminished, the utility of enhancement decreased. Continuous increase of the safe area for treatment and decrease of the utility of enhancement were observed along with the abatement of the thickness of the interface layer展开更多
Magnetic measurement is a typical inverse problem in Biomedical field. In this kind of problem we always need to locate the positions and moments of one or more magnetic dipoles. Although using the traditional methods...Magnetic measurement is a typical inverse problem in Biomedical field. In this kind of problem we always need to locate the positions and moments of one or more magnetic dipoles. Although using the traditional methods to solve this kind of inverse problem has all kinds of shortcomings, BPNN (Back Propagation Neural Networks) method can be used to solve this typical inverse problem fast enough for real time measurement. In the traditional BPNN method, gradient descent search method is performed for error propagation. In this paper the authors propose a new algorithm that Newton method is performed for error propagation. For the cost function is highly nonconvex in the magnetic measurement problem, the new kind of BPNN can get convergent results quickly and precisely. A simulation result for this method is also presented.展开更多
Magnetotactic bacteria are a diverse group of motile prokaryotes that are ubiquitous in aquatic habitats and cosmopolitan in distribution. In this study, we collected magnetotactic bacteria from the Mediterranean Sea....Magnetotactic bacteria are a diverse group of motile prokaryotes that are ubiquitous in aquatic habitats and cosmopolitan in distribution. In this study, we collected magnetotactic bacteria from the Mediterranean Sea. A remarkable diversity of morphotypes was observed, including multicellular types that seemed to differ from those previously found in North and South America. Another interesting organism was one with magnetosomes arranged in a six-stranded bundle which occupied one third of the cell width. The magnetosome bundle was evident even under optic microscopy. These cells were connected together and swam as a linear entire unit. Magnetosomes did not always align up to form a straight linear chain. A chain composed of rectangle magnetosomes bent at a posi- tion with an oval crystal. High resolution transmission electron microscopy analysis of the crystal at the pivotal position suggested uncompleted formation of the crystal. This is the first report of Mediterranean magnetotactic bacteria, which should be useful for studies of biogeochemical cycling and geohistory of the Mediterranean Sea.展开更多
Magnetotactic bacteria (MTB) as biosorbents for the adsorption of Au(Ⅲ) and Cu(Ⅱ) ions from aqueous solution have been investigated. The optimum adsorption conditions for both metal ions were the initial pH sc...Magnetotactic bacteria (MTB) as biosorbents for the adsorption of Au(Ⅲ) and Cu(Ⅱ) ions from aqueous solution have been investigated. The optimum adsorption conditions for both metal ions were the initial pH scope of 1-5.5 for Au(Ⅲ) and 2.0-4.5 for Cu(Ⅱ), room temperature, biomass concentration of 10.0g.L^-1 and sorotion du-ration more than 10 min. When the initial metal concentration were within 500mg.L^-1, the maximum biosorption capacity of 1.0g of MTB (dry mass basis) for Au(Ⅲ) and Cu(Ⅱ) were calculated as 505.2mg of Au(Ⅲ) and 493.1mg of.Cu(Ⅱ) by Langmuir model in single system, respectively. The isotherm equilibrium of Au(Ⅲ) and Cu(Ⅱ) ions in the Au-Cu binary system reflected a unique phenomenon that the adsorption of Au(Ⅲ) was rein-forced and that of Cu(Ⅱ) prohibited, compared respectively-with their performances in the single metal system.When the,concentration of-Au(Ⅲ) and Cu(Ⅱ). were below 80mg.L^-1, the waste waterafter MTB treating, wasbelow 1.0mg.L^-1, which is in conformity with Environmental Performance Standards (EPS) of Canada. Besides, all the kinetic data were fitted well to the pseudo second-order kinetic model with a high correlation coefficient (R^2〉0.999).展开更多
Magnetic starch particles (MSPs) were synthesized in water-in-oil mieroemulsion at room temperature. MSPs were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FTI...Magnetic starch particles (MSPs) were synthesized in water-in-oil mieroemulsion at room temperature. MSPs were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FTIR), zeta potential system, thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM). The average diameter of the MSPs was 220 nm, dispersed with well-proportioned size and magnetic resonance, the saturation magnetization was 3.64 A.mR/kg. MSP was coated with poly-L-lysine (PLL), and then the surface of PLL-MSP was combined with fluorescein isothiocynate (FITC). Results show that fluorescent/magnetic starch particles (FMSPs) are of stable photo-bleaching capability compared with free FITC, with low bio-toxicity and certain function of magnetic separation. It is expected that FMSPs are bifimctional nano-materials including fluorescence labelling and magnetic separation.展开更多
100%green carbon foam from the fibrous fruits of Platanus Orientalis-L(Plane)along with the tar oil as binder has been prepared using a powder molding technique.The objective was to develop a porous monolithic carbon ...100%green carbon foam from the fibrous fruits of Platanus Orientalis-L(Plane)along with the tar oil as binder has been prepared using a powder molding technique.The objective was to develop a porous monolithic carbon from biomaterials with a considerable strength necessary for various physical,thermal and electromagnetic shielding applications.Fast carbonization was carried out at1000°C under the cover of Plane tree pyrolyzed seeds without using any external protective gas.For comparative analysis,some samples were mixed with5%(mass fraction)iron chloride during the molding process.Iron chloride being a graphitization catalyst and activating agent helped in increasing the specific surface area from88to294m2/g with a25%decrease in flexural strength.Thermal stability was improved due to the incorporation of more graphitic phases in the sample resulting in a little higher thermal conductivity from0.22to0.67W/(m·K).The catalytic carbon foam exhibited shielding effectiveness of more than20dB over the X-band frequency.Absorption was dominant with only8.26%?10.33%reflectance,indicating an absorption dominant shielding mechanism.The new material is quite suitable for high temperature thermal insulation being lightweight,highly porous with interconnected porous morphology most of which is preserved from the original biomaterial.展开更多
Sense of touch is one of the important information from environment for human to live in daily life. Haptic interface is a hot topic in virtual reality but almost all of the devices focus on fingers and hands as targe...Sense of touch is one of the important information from environment for human to live in daily life. Haptic interface is a hot topic in virtual reality but almost all of the devices focus on fingers and hands as targets. In this paper, we focus on the foot haptic device with magnetic flied sensitive elastomer (MSE). We developed a haptic unit used as a magnetic field generator for MSE and contact point of foot haptic device. MSE samples mixed with 80 wt% carbonyl iron particles were prepared and evaluated with the developed magnet. Experimental results show that the mechanical property of the haptic unit can be modeled with the adjustable friction element. This property has a good advantage for the haptic unit.展开更多
This research elaborates magnetohydrodynamics (MHD) impact on non-Newtonian (Williamson) fluid flow by stretchable rotating disks.Both disks are rotating with different angular velocities and different stretching rate...This research elaborates magnetohydrodynamics (MHD) impact on non-Newtonian (Williamson) fluid flow by stretchable rotating disks.Both disks are rotating with different angular velocities and different stretching rates.Viscous dissipation aspect is considered for energy expression formulation.Entropy generation analysis is described via implementation of thermodynamic second law.Chemical processes (heterogeneous and homogeneous) subjected to entropy generation are introduced first time in literature.Boundary-layer approach is employed for modeling.Apposite variables are introduced for non-dimensionalization of governing systems.Homotopy procedure yields convergence of solutions subjected to computations of highly nonlinear expressions.The significant characteristics of sundry factors against thermal,velocity and solutal fields are described graphically.Besides,tabular results are addressed for engineering quantities (skin-friction coefficient,Nusselt number).The outcomes certify an increment in temperature distribution for Weissenberg (We) and Eckert (Ec) numbers.展开更多
On the base of benzimidazole and benzofuran containing heterocyclic system, several derivatives with expected biological activity were synthesized. 2,3-diaminodibenzofuran was the primary substance. Adding various cyc...On the base of benzimidazole and benzofuran containing heterocyclic system, several derivatives with expected biological activity were synthesized. 2,3-diaminodibenzofuran was the primary substance. Adding various cyclic agents, 2-phenil was got, 2-(o-chlorophenil), 2-(o-oxyphenil), 2-chlorometyl- and 2-hydroximethyl-3H-benzo[b[furo(3,2-f] benzimidazoles. The aforementioned substances were characterized by IR and NMR spectroscopy.展开更多
Objective: To study the growth and differentiation of superparamagnetie iron oxides(SPIOs) labeled neural stem cells (NSCs). Methods: After NSCs were cultured and subcuhured from newborn rat brain, they were mag...Objective: To study the growth and differentiation of superparamagnetie iron oxides(SPIOs) labeled neural stem cells (NSCs). Methods: After NSCs were cultured and subcuhured from newborn rat brain, they were magnetically labeled with ferumoxides (a kind of SPIOs ). Growth, differentiation and other biology properties of the cells were investigated with immunocytochemistry, transmission electron microscopy (TEM) and Prussian blue staining. Results: Nestin positive cells were found in the culture and offspring clones. NSCs could be differentiated into positive GFAP and NF200 cells in serum culture. When NSCs incubated with ferumoxides, the iron particles were seen in intracellular as well as in offspring clones. With the increase in concentration of ferumoxides (5.6-11.2/μg/ml), ferumoxides showed no significant difference effects on the growth and differentiation of NSCs. When the concentration of ferumoxides exceeded 22.4μg/ml ,there was significant difference(P〈0.05). Conclusion: We successfully label NSCs with ferumoxides,it is useful for tracking of magnetic labeled NSCs in vivo with MRI.展开更多
Clostridium septicum(C.septicum)gas gangrene is well documented in the literature,typically in the setting of trauma or immunosuppression.In this paper,we report a unique case of spontaneous clostridial myonecrosis in...Clostridium septicum(C.septicum)gas gangrene is well documented in the literature,typically in the setting of trauma or immunosuppression.In this paper,we report a unique case of spontaneous clostridial myonecrosis in a patient with Crohn's disease and sulfasalazineinduced neutropenia.The patient presented with left thigh pain,vomiting and diarrhea.Blood tests demonstrated a profound neutropenia,and magnetic resonance imaging of the thigh confirmed extensive myonecrosis.The patient underwent emergency hip disarticulation,followed by hemicolectomy.C.septicum was cultured from the blood.Following completion of antibiotic therapy,the patient developed myonecrosis of the right pectoral muscle necessitating further debridement,and remains on lifelong prophylactic antibiotic therapy.展开更多
Objective:To evaluate the in vitro and in vivo toxicity of self-prepared nanosized Fe2O3, which has the potential implication in tumor hyperthermia. Methods: Fe2O3 nanoparticles were prepared by improving co-precipi...Objective:To evaluate the in vitro and in vivo toxicity of self-prepared nanosized Fe2O3, which has the potential implication in tumor hyperthermia. Methods: Fe2O3 nanoparticles were prepared by improving co-precipitation, which characterization was detected by TEM, XRD, CMIAS, EDS. MTT assay was used to evaluate the in vitro cytotoxicity test; hemolytic test was carried out to estimate whether it has blood toxicity; Fe2O3 suspended in sterile 0.9% NaCl was intraperitoneally injected into Kumning mouse to calculate the LD50 ; micronucleus (MN) were reckoned to identify whether it is genotoxic. Results:The nanoparticles are brown spherical particles with diameter ranging from 8 to 15 nm, which have good decentralization and stability. The experiments also showed that the toxicity of the material on mouse fibroblast (L-929) cell lines was 0 - 1 degree ; it has no hemolysis activity; LD50 arrived at 5.45 g/kg^-1 after intraperitoneal injection of 1 ml suspension; micronucleus test showed that it has no genotoxic effects either. Conclusion: The results showed that the Fe2O3 nanoparticles are prepared successfully, the self-prepared nanosized Fe2O3 is a kind of high biocompatibility materials and perhaps it is suitable for further application in tumor hyperthermia.展开更多
基金This work is supported by nology Cooperation Plan of LKS[2013]15), the 2012 Doctor Normal University of China the Science and Tech- Guizhou Province (J- Foundation of Guizhou (Xun Zhou) Scholars of Ministry of Education of China, Ph.D. Programs Foundation of Ministry of Education of China (No.20120171120011), the Open Fund of the State Key Laboratory on Integrated Optoelectronics of Jilin University (No.IOKL2013KF14), the National Natural Science Foundation of China (No.61273310).
文摘The ferromagnetic manganese doped TiN films were grown by plasma assisted molecular beam epitaxy on MgO(001) substrates. The nitrogen concentration and the ratio of manganese at Ti lattice sites increase after the plasma annealing post treatment. TIN(002) peak shifts toward low angle direction and TiN(111) peak disappears after the post treatment. The lattice expansion and peak shift are mainly ascribed to the reduction of nitrogen vacancies in films. The magnetism was suppressed in as-prepared sample due to the pinning effect of the nitrogen vacancies at defect sites or interface. The magnetism can be activated by the plasma implantation along with nitrogen vacancies reduce. The decrease of nitrogen vacancies leads to the enhancement of ferromagnetism.
文摘Focal nodular hyperplasia(FNH) of the liver is a benign lesion occurring in 0.6%-3% of the general population that probably reflects a local hyperplastic response of hepatocytes to a vascular abnormality. Most lesions are diagnosed incidentally and the natural history of the disease remains largely unknown. It has been shown that most FNH remain stable, or even regress, over a long follow-up period. We present a patient with FNH of the liver who was followed up for 7 years. A 26-yearold woman with a 5-year history of oral contraceptive use was referred to our hospital in February 2005 for further examination of a liver tumour. The diagnosis of FNH was made using magnetic resonance(MR) imaging with hepatospecific contrast media; this technique allows a correct diagnosis, in particular distinguishing FNH from hepatic adenoma, avoiding an invasive procedure such as the lesion biopsy. After 7-year from the diagnosis, we observed the complete spontaneous regression of the lesion by enhanced MR scanning. In this patient, discontinuation of oral contraceptive use and two childbirths may have influenced the natural history of FNH. To our knowledge, in the English literature there is no report illustrating a complete regression of giant FNH but only studies of decreasing in size. The present case suggests that a young patient with giant FNH should be managed conservatively rather than by resection, because FNH has the potential for spontaneous regression.
文摘Objective To investigate the influence of vitamin D receptor (VDR) gene polymorphisms on susceptibility to type 1 diabetes mellitus (T1DM) in the Chinese Han population. Method One hundred and thirty-six Chinese Han people, including 54 T1DM patients and 82 unrelated healthy subjects as control were genotyped by polymerase chain reaction-restriction fragment length polymorphism for three restriction sites in the VDR gene, which were ApaI, TaqI, and BamL Results The frequency of B allele of BsmI site in VDR gene was significantly higher in T1DM patients than in healthy subjects ( P = 0. 033 ) while no difference was found between the two groups in the distribution of ApaI and TaqI polymorphisms. Conclusion The BsmI polymorphism of VDR gene may be associated with the susceptibihty to T1DM in the Chinese Han population of Beijing.
基金the Development Plan for Innovation Teams of Ministry of Education (2005-33)the National Natural Science Foundation of China (30471653)the Natural Science Foundation of Chongqing (2006BA5020)
文摘After interface layer was simulated by the magnetic nano-particles in the egg white phantom, high intensity focused ultrasound (HIFU) at the same dosage was introduced to radiate the phantom in different depths to blow the acoustic interface layer to mimic "point" exposure. The results showed that the volumes of biological focal region (BFR) were enlarged when the acoustic focal region (AFR) is close with interface layer. This meant that the magnetic nano-particles enhanced the therapeutic efficiency of HIFU. When the distance of the AFR from the interface layer was 10 mm, the size and shape of the BFR were similar with those of the control group, but a larger lesion at the interface, which was harmful for treatment, was observed. When the distance of the AFR to the interface layer increased to 30 mm, the size and shape of the BFR were also similar to those of the control group. When the thickness of the interface layer diminished, the utility of enhancement decreased. Continuous increase of the safe area for treatment and decrease of the utility of enhancement were observed along with the abatement of the thickness of the interface layer
文摘Magnetic measurement is a typical inverse problem in Biomedical field. In this kind of problem we always need to locate the positions and moments of one or more magnetic dipoles. Although using the traditional methods to solve this kind of inverse problem has all kinds of shortcomings, BPNN (Back Propagation Neural Networks) method can be used to solve this typical inverse problem fast enough for real time measurement. In the traditional BPNN method, gradient descent search method is performed for error propagation. In this paper the authors propose a new algorithm that Newton method is performed for error propagation. For the cost function is highly nonconvex in the magnetic measurement problem, the new kind of BPNN can get convergent results quickly and precisely. A simulation result for this method is also presented.
文摘Magnetotactic bacteria are a diverse group of motile prokaryotes that are ubiquitous in aquatic habitats and cosmopolitan in distribution. In this study, we collected magnetotactic bacteria from the Mediterranean Sea. A remarkable diversity of morphotypes was observed, including multicellular types that seemed to differ from those previously found in North and South America. Another interesting organism was one with magnetosomes arranged in a six-stranded bundle which occupied one third of the cell width. The magnetosome bundle was evident even under optic microscopy. These cells were connected together and swam as a linear entire unit. Magnetosomes did not always align up to form a straight linear chain. A chain composed of rectangle magnetosomes bent at a posi- tion with an oval crystal. High resolution transmission electron microscopy analysis of the crystal at the pivotal position suggested uncompleted formation of the crystal. This is the first report of Mediterranean magnetotactic bacteria, which should be useful for studies of biogeochemical cycling and geohistory of the Mediterranean Sea.
基金Supported by the National Natural Science Foundation of China (No.20206024) and the Natural Science Foundation of Tianjin (No.07JCYBJC06800).
文摘Magnetotactic bacteria (MTB) as biosorbents for the adsorption of Au(Ⅲ) and Cu(Ⅱ) ions from aqueous solution have been investigated. The optimum adsorption conditions for both metal ions were the initial pH scope of 1-5.5 for Au(Ⅲ) and 2.0-4.5 for Cu(Ⅱ), room temperature, biomass concentration of 10.0g.L^-1 and sorotion du-ration more than 10 min. When the initial metal concentration were within 500mg.L^-1, the maximum biosorption capacity of 1.0g of MTB (dry mass basis) for Au(Ⅲ) and Cu(Ⅱ) were calculated as 505.2mg of Au(Ⅲ) and 493.1mg of.Cu(Ⅱ) by Langmuir model in single system, respectively. The isotherm equilibrium of Au(Ⅲ) and Cu(Ⅱ) ions in the Au-Cu binary system reflected a unique phenomenon that the adsorption of Au(Ⅲ) was rein-forced and that of Cu(Ⅱ) prohibited, compared respectively-with their performances in the single metal system.When the,concentration of-Au(Ⅲ) and Cu(Ⅱ). were below 80mg.L^-1, the waste waterafter MTB treating, wasbelow 1.0mg.L^-1, which is in conformity with Environmental Performance Standards (EPS) of Canada. Besides, all the kinetic data were fitted well to the pseudo second-order kinetic model with a high correlation coefficient (R^2〉0.999).
基金Project(200501) supported by the "985" Program of China
文摘Magnetic starch particles (MSPs) were synthesized in water-in-oil mieroemulsion at room temperature. MSPs were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FTIR), zeta potential system, thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM). The average diameter of the MSPs was 220 nm, dispersed with well-proportioned size and magnetic resonance, the saturation magnetization was 3.64 A.mR/kg. MSP was coated with poly-L-lysine (PLL), and then the surface of PLL-MSP was combined with fluorescein isothiocynate (FITC). Results show that fluorescent/magnetic starch particles (FMSPs) are of stable photo-bleaching capability compared with free FITC, with low bio-toxicity and certain function of magnetic separation. It is expected that FMSPs are bifimctional nano-materials including fluorescence labelling and magnetic separation.
基金Project(CX201627) supported by the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University,China
文摘100%green carbon foam from the fibrous fruits of Platanus Orientalis-L(Plane)along with the tar oil as binder has been prepared using a powder molding technique.The objective was to develop a porous monolithic carbon from biomaterials with a considerable strength necessary for various physical,thermal and electromagnetic shielding applications.Fast carbonization was carried out at1000°C under the cover of Plane tree pyrolyzed seeds without using any external protective gas.For comparative analysis,some samples were mixed with5%(mass fraction)iron chloride during the molding process.Iron chloride being a graphitization catalyst and activating agent helped in increasing the specific surface area from88to294m2/g with a25%decrease in flexural strength.Thermal stability was improved due to the incorporation of more graphitic phases in the sample resulting in a little higher thermal conductivity from0.22to0.67W/(m·K).The catalytic carbon foam exhibited shielding effectiveness of more than20dB over the X-band frequency.Absorption was dominant with only8.26%?10.33%reflectance,indicating an absorption dominant shielding mechanism.The new material is quite suitable for high temperature thermal insulation being lightweight,highly porous with interconnected porous morphology most of which is preserved from the original biomaterial.
文摘Sense of touch is one of the important information from environment for human to live in daily life. Haptic interface is a hot topic in virtual reality but almost all of the devices focus on fingers and hands as targets. In this paper, we focus on the foot haptic device with magnetic flied sensitive elastomer (MSE). We developed a haptic unit used as a magnetic field generator for MSE and contact point of foot haptic device. MSE samples mixed with 80 wt% carbonyl iron particles were prepared and evaluated with the developed magnet. Experimental results show that the mechanical property of the haptic unit can be modeled with the adjustable friction element. This property has a good advantage for the haptic unit.
文摘This research elaborates magnetohydrodynamics (MHD) impact on non-Newtonian (Williamson) fluid flow by stretchable rotating disks.Both disks are rotating with different angular velocities and different stretching rates.Viscous dissipation aspect is considered for energy expression formulation.Entropy generation analysis is described via implementation of thermodynamic second law.Chemical processes (heterogeneous and homogeneous) subjected to entropy generation are introduced first time in literature.Boundary-layer approach is employed for modeling.Apposite variables are introduced for non-dimensionalization of governing systems.Homotopy procedure yields convergence of solutions subjected to computations of highly nonlinear expressions.The significant characteristics of sundry factors against thermal,velocity and solutal fields are described graphically.Besides,tabular results are addressed for engineering quantities (skin-friction coefficient,Nusselt number).The outcomes certify an increment in temperature distribution for Weissenberg (We) and Eckert (Ec) numbers.
文摘On the base of benzimidazole and benzofuran containing heterocyclic system, several derivatives with expected biological activity were synthesized. 2,3-diaminodibenzofuran was the primary substance. Adding various cyclic agents, 2-phenil was got, 2-(o-chlorophenil), 2-(o-oxyphenil), 2-chlorometyl- and 2-hydroximethyl-3H-benzo[b[furo(3,2-f] benzimidazoles. The aforementioned substances were characterized by IR and NMR spectroscopy.
基金Supported by National Natural Science Foundation of Chi-na (330370500)Postdoctoral Science Foundation of China(2003033363)the CQUMS Excellent Doctoral Founda-tion
文摘Objective: To study the growth and differentiation of superparamagnetie iron oxides(SPIOs) labeled neural stem cells (NSCs). Methods: After NSCs were cultured and subcuhured from newborn rat brain, they were magnetically labeled with ferumoxides (a kind of SPIOs ). Growth, differentiation and other biology properties of the cells were investigated with immunocytochemistry, transmission electron microscopy (TEM) and Prussian blue staining. Results: Nestin positive cells were found in the culture and offspring clones. NSCs could be differentiated into positive GFAP and NF200 cells in serum culture. When NSCs incubated with ferumoxides, the iron particles were seen in intracellular as well as in offspring clones. With the increase in concentration of ferumoxides (5.6-11.2/μg/ml), ferumoxides showed no significant difference effects on the growth and differentiation of NSCs. When the concentration of ferumoxides exceeded 22.4μg/ml ,there was significant difference(P〈0.05). Conclusion: We successfully label NSCs with ferumoxides,it is useful for tracking of magnetic labeled NSCs in vivo with MRI.
文摘Clostridium septicum(C.septicum)gas gangrene is well documented in the literature,typically in the setting of trauma or immunosuppression.In this paper,we report a unique case of spontaneous clostridial myonecrosis in a patient with Crohn's disease and sulfasalazineinduced neutropenia.The patient presented with left thigh pain,vomiting and diarrhea.Blood tests demonstrated a profound neutropenia,and magnetic resonance imaging of the thigh confirmed extensive myonecrosis.The patient underwent emergency hip disarticulation,followed by hemicolectomy.C.septicum was cultured from the blood.Following completion of antibiotic therapy,the patient developed myonecrosis of the right pectoral muscle necessitating further debridement,and remains on lifelong prophylactic antibiotic therapy.
基金Grant sponsor:National Natural Science Foundation of China,Grant number:30371830Grant sponsor:National Hi-tech research and development program of China,Grant number:2002AA302207+3 种基金 Grant sponsor:Natural Science Foundation of Jiangsu,Grant number:BK2001003Grant sponsor:Hi-tech research pro-gram of Jiangsu,Grant number:BG2001006 Grant sponsor:Key Project of Chinese Traditional Medicine of Jiangsu,Grant number:H027Grant sponsor:Sci-ence Foundation of Southeast University,Grant number:9223001162
文摘Objective:To evaluate the in vitro and in vivo toxicity of self-prepared nanosized Fe2O3, which has the potential implication in tumor hyperthermia. Methods: Fe2O3 nanoparticles were prepared by improving co-precipitation, which characterization was detected by TEM, XRD, CMIAS, EDS. MTT assay was used to evaluate the in vitro cytotoxicity test; hemolytic test was carried out to estimate whether it has blood toxicity; Fe2O3 suspended in sterile 0.9% NaCl was intraperitoneally injected into Kumning mouse to calculate the LD50 ; micronucleus (MN) were reckoned to identify whether it is genotoxic. Results:The nanoparticles are brown spherical particles with diameter ranging from 8 to 15 nm, which have good decentralization and stability. The experiments also showed that the toxicity of the material on mouse fibroblast (L-929) cell lines was 0 - 1 degree ; it has no hemolysis activity; LD50 arrived at 5.45 g/kg^-1 after intraperitoneal injection of 1 ml suspension; micronucleus test showed that it has no genotoxic effects either. Conclusion: The results showed that the Fe2O3 nanoparticles are prepared successfully, the self-prepared nanosized Fe2O3 is a kind of high biocompatibility materials and perhaps it is suitable for further application in tumor hyperthermia.