目的设计一种改良的枢椎椎板螺钉置钉方法并应用于临床，使螺钉置入更简单、更准确。方法改良枢椎椎板螺钉置钉方法的进钉点仍为棘突和椎板的交界处，但在椎板中份用磨钻磨除少许皮质开窗，用刮匙刮除松质骨，保留椎板内板，用手钻沿着...目的设计一种改良的枢椎椎板螺钉置钉方法并应用于临床，使螺钉置入更简单、更准确。方法改良枢椎椎板螺钉置钉方法的进钉点仍为棘突和椎板的交界处，但在椎板中份用磨钻磨除少许皮质开窗，用刮匙刮除松质骨，保留椎板内板，用手钻沿着枢椎椎板钻孔，在直视下通过开窗处，再继续向前钻入，探针探查钉道并攻丝后置入直径3.5~4.0mrn、长度24~30mrn螺钉。临床应用26例，其中男17例，女9例，平均年龄56.7岁。结果共置入42枚枢椎椎板螺钉，螺钉平均长度为27.1 mm(24~30 m m ),术中无需透视，术中和术后无明显技术相关的并发症发生。术后即刻或随访CT示椎板螺钉位置正确，均位于椎板间。全组病例平均随访13.4个月，未发生螺钉松动、脱出或断裂。结论改良的枢椎椎板螺钉置入技术操作简单，无需透视，并保证了螺钉处于正确位置。展开更多
A concept of two different reaction zones was proposed based on the FCC reaction mechanism. The concept was used to design a novel reactor with corresponding operation measures. Experiments were conducted on the newly...A concept of two different reaction zones was proposed based on the FCC reaction mechanism. The concept was used to design a novel reactor with corresponding operation measures. Experiments were conducted on the newly designed pilot plant riser reactor. In comparison with the conventional FCC at relatively equivalent conversion, the pilot plant test results showed that the olefin content in the cracked naphtha dropped by 12.4%, and both contents of iso paraffin and aromatic increased by 6%, and its MON increased by 1.3 units while maintaining the RON of the naphtha unchanged, and its sulfur content reduced by 15% with a significant extension of its induction period for Shengli VGO+VR. The run test results of commercial trial were conformable with the results of pilot plant test.展开更多
Two-level finite element approximation to stream function form of unsteady Navier-Stokes equations is studied.This algorithm involves solving one nonlinear system on a coarse grid and one linear problem on a fine grid...Two-level finite element approximation to stream function form of unsteady Navier-Stokes equations is studied.This algorithm involves solving one nonlinear system on a coarse grid and one linear problem on a fine grid.Moreover,the scaling between these two grid sizes is super-linear.Approximation,stability and convergence aspects of a fully discrete scheme are analyzed.At last a numrical example is given whose results show that the algorithm proposed in this paper is effcient.展开更多
Direct use values of forest ecosystem have been recognized apparently due toits easy and convenient assessment, while indirect use values are usually neglected because they arenot easy to be recognized by the public. ...Direct use values of forest ecosystem have been recognized apparently due toits easy and convenient assessment, while indirect use values are usually neglected because they arenot easy to be recognized by the public. For a nature reserve with forest ecosystem, the mostimportant economic values are the indirect use values, which provide human beings and other livingthings with beneficial services through ecological processes and functions. In this case study, aquantifying framework to estimate the annual indirect use values of forest ecosystem has beenestablished in Yaoluoping National Nature Reserve based on alternative cost method and opportunitycost method. The ecological functions assessed in the study relate to six aspects: soil protection,water conservation, CO_2 fixation, nutrient cycling, pollutant decomposition and disease and pestcontrol. These ecological functions provide an economic value of 86.1xl0~6 yuan (RMB) per year(US$10.37xl0~6), which is 25 times higher than the opportunity cost for regular timber production.This study can contribute to the monetary assessment of indirect use values of forest biodiversityand to the conservation and sustainable use of nature reserves.展开更多
Latent functionally thermal fluids (LFTF) are a novel kind of heat storage and heat transfer fluids that in- clude phase change microcapsule slurry and phase change emulsion (PCE). They have much greater apparent spec...Latent functionally thermal fluids (LFTF) are a novel kind of heat storage and heat transfer fluids that in- clude phase change microcapsule slurry and phase change emulsion (PCE). They have much greater apparent specific heats and higher heat transfer abilities in the phase change temperature range than conventional single-phase heat transfer fluids such as water. Thus they are advantageous in the field of the convective heat transfer enhancement and energy transport. In this paper, some thermal physical prop- erties such as viscosity, fusion heat and apparent specific heat (cp) are measured, and the influences of some factors (such as selection of surfactants, preparation method, temperature, mixing ratio of surfactants and mass concentration of phase change material) on them are discussed. The study shows that: 1) the viscosity of the PCE prepared in the present work is lower than that reported in the literature; 2) its ap- parent specific heat value for the phase change temperature region is high and proportionally increases with the concentration of phase change material.展开更多
Conjugated, conductive polymers are a kind of important organic macromolecules, which has found appli- cations in a variety of areas. The application of conjugated polymers in developing fluorescent biosensors represe...Conjugated, conductive polymers are a kind of important organic macromolecules, which has found appli- cations in a variety of areas. The application of conjugated polymers in developing fluorescent biosensors represents the merge of polymer sciences and biological sciences. Conju- gated polymers are very good light harvesters as well as fluorescent polymers, and they are also “molecular wires”. Through elaborate designs, these important features, i.e. efficient light harvesting and electron/energy transfer, can be used as signal amplification in fluorescent biosensors. This might significantly improve the sensitivity of conjugated polymer-based biosensors. In this article, we reviewed the application of conjugated polymers, via either electron transfer or energy transfer, to detections of gene targets, an- tibodies or enzymes. We also reviewed recent efforts in con- jugated polymer-based solid-state sensor designs as well as chip-based multiple target detection. Possible directions in this conjugated polymer-based biosensor area are also dis- cussed.展开更多
文摘目的设计一种改良的枢椎椎板螺钉置钉方法并应用于临床，使螺钉置入更简单、更准确。方法改良枢椎椎板螺钉置钉方法的进钉点仍为棘突和椎板的交界处，但在椎板中份用磨钻磨除少许皮质开窗，用刮匙刮除松质骨，保留椎板内板，用手钻沿着枢椎椎板钻孔，在直视下通过开窗处，再继续向前钻入，探针探查钉道并攻丝后置入直径3.5~4.0mrn、长度24~30mrn螺钉。临床应用26例，其中男17例，女9例，平均年龄56.7岁。结果共置入42枚枢椎椎板螺钉，螺钉平均长度为27.1 mm(24~30 m m ),术中无需透视，术中和术后无明显技术相关的并发症发生。术后即刻或随访CT示椎板螺钉位置正确，均位于椎板间。全组病例平均随访13.4个月，未发生螺钉松动、脱出或断裂。结论改良的枢椎椎板螺钉置入技术操作简单，无需透视，并保证了螺钉处于正确位置。
文摘A concept of two different reaction zones was proposed based on the FCC reaction mechanism. The concept was used to design a novel reactor with corresponding operation measures. Experiments were conducted on the newly designed pilot plant riser reactor. In comparison with the conventional FCC at relatively equivalent conversion, the pilot plant test results showed that the olefin content in the cracked naphtha dropped by 12.4%, and both contents of iso paraffin and aromatic increased by 6%, and its MON increased by 1.3 units while maintaining the RON of the naphtha unchanged, and its sulfur content reduced by 15% with a significant extension of its induction period for Shengli VGO+VR. The run test results of commercial trial were conformable with the results of pilot plant test.
文摘Two-level finite element approximation to stream function form of unsteady Navier-Stokes equations is studied.This algorithm involves solving one nonlinear system on a coarse grid and one linear problem on a fine grid.Moreover,the scaling between these two grid sizes is super-linear.Approximation,stability and convergence aspects of a fully discrete scheme are analyzed.At last a numrical example is given whose results show that the algorithm proposed in this paper is effcient.
文摘Direct use values of forest ecosystem have been recognized apparently due toits easy and convenient assessment, while indirect use values are usually neglected because they arenot easy to be recognized by the public. For a nature reserve with forest ecosystem, the mostimportant economic values are the indirect use values, which provide human beings and other livingthings with beneficial services through ecological processes and functions. In this case study, aquantifying framework to estimate the annual indirect use values of forest ecosystem has beenestablished in Yaoluoping National Nature Reserve based on alternative cost method and opportunitycost method. The ecological functions assessed in the study relate to six aspects: soil protection,water conservation, CO_2 fixation, nutrient cycling, pollutant decomposition and disease and pestcontrol. These ecological functions provide an economic value of 86.1xl0~6 yuan (RMB) per year(US$10.37xl0~6), which is 25 times higher than the opportunity cost for regular timber production.This study can contribute to the monetary assessment of indirect use values of forest biodiversityand to the conservation and sustainable use of nature reserves.
基金the National Natural Science Foundation of China(Grants No.50076020, 50436020)the National Key Basic Research Special Fund Project(Grant No.G2000026309).
文摘Latent functionally thermal fluids (LFTF) are a novel kind of heat storage and heat transfer fluids that in- clude phase change microcapsule slurry and phase change emulsion (PCE). They have much greater apparent specific heats and higher heat transfer abilities in the phase change temperature range than conventional single-phase heat transfer fluids such as water. Thus they are advantageous in the field of the convective heat transfer enhancement and energy transport. In this paper, some thermal physical prop- erties such as viscosity, fusion heat and apparent specific heat (cp) are measured, and the influences of some factors (such as selection of surfactants, preparation method, temperature, mixing ratio of surfactants and mass concentration of phase change material) on them are discussed. The study shows that: 1) the viscosity of the PCE prepared in the present work is lower than that reported in the literature; 2) its ap- parent specific heat value for the phase change temperature region is high and proportionally increases with the concentration of phase change material.
文摘Conjugated, conductive polymers are a kind of important organic macromolecules, which has found appli- cations in a variety of areas. The application of conjugated polymers in developing fluorescent biosensors represents the merge of polymer sciences and biological sciences. Conju- gated polymers are very good light harvesters as well as fluorescent polymers, and they are also “molecular wires”. Through elaborate designs, these important features, i.e. efficient light harvesting and electron/energy transfer, can be used as signal amplification in fluorescent biosensors. This might significantly improve the sensitivity of conjugated polymer-based biosensors. In this article, we reviewed the application of conjugated polymers, via either electron transfer or energy transfer, to detections of gene targets, an- tibodies or enzymes. We also reviewed recent efforts in con- jugated polymer-based solid-state sensor designs as well as chip-based multiple target detection. Possible directions in this conjugated polymer-based biosensor area are also dis- cussed.
