The canonical quantum teleportation of two-particle arbitrary state is realized by means of phase operator and number operator. The maximally entangled eigenstates between the difference of phase operators and the sum...The canonical quantum teleportation of two-particle arbitrary state is realized by means of phase operator and number operator. The maximally entangled eigenstates between the difference of phase operators and the sum of number operators are considered as the quantum channels. In contrast to the standard quantum teleportation, the different unitary local operation of canonical teleportation can be simplified by a general expression.展开更多
A novel charge exchanging compensation (CEC) technique is proposed for a wideband sample-and-hold (S/H) circuit applied in an IF sampling ADC. The CEC technique compensates the sampling bandwidth by eliminating th...A novel charge exchanging compensation (CEC) technique is proposed for a wideband sample-and-hold (S/H) circuit applied in an IF sampling ADC. The CEC technique compensates the sampling bandwidth by eliminating the impact from finite on-resistance of the sampling switch, and avoids increasing clock feedthrough and charge injection. Meanwhile, a low power two stage OTA with a class AB output stage is designed to provide the S/H a 3Vp-p input range under 1.8V power. The S/H achieves a 94dB spurious-free dynamic range for a 200MHz input signal at a 100Ms/s sample rate and consumes only 26mW with a 5.5pF load.展开更多
A novel 6-PSS flexible parallel mechanism was presented,which employed wide-range flexure hinges as passive joints.The proposed mechanism features micron level positioning accuracy over cubic centimeter scale workspac...A novel 6-PSS flexible parallel mechanism was presented,which employed wide-range flexure hinges as passive joints.The proposed mechanism features micron level positioning accuracy over cubic centimeter scale workspace.A three-layer back-propagation(BP) neural network was utilized to the kinematics analysis,in which learning samples containing 1 280 groups of data based on stiffness-matrix method were used to train the BP model.The kinematics performance was accurately calculated by using the constructed BP model with 19 hidden nodes.Compared with the stiffness model,the simulation and numerical results validate that BP model can achieve millisecond level computation time and micron level calculation accuracy.The concept and approach outlined can be extended to a variety of applications.展开更多
Throughout Jazz (2004), Morrison revises language and stakes a generic revolution within her linguistic one. Problematising language, she interrogates its role by disrupting all metaphoric operation and normative op...Throughout Jazz (2004), Morrison revises language and stakes a generic revolution within her linguistic one. Problematising language, she interrogates its role by disrupting all metaphoric operation and normative operations of traditional Westem narratology, challenging ontological distinction, and undermining a novelistic claim of/for reality. Morrison creates the novel as a parody of itself. As a metafictional object, she (re)visions the fiction with multiple agendas--a means to interrogate the reality of its constitution and to implicate the political consequences inherent in that constitutional process of construction. By creating a series of antagonisms, oppositions, contradictions, equivalences, and intertextualities, Morrison transforms (and transmutes) novelistic "hostility" into a generic "trauma" simultaneously rendering it as realistic experience, historic event, personal story, collective memory, narrative device, and psychological phenomena. Exposing trauma by virtue of its linguistic symptoms, Morrison draws attention to the underlying mechanisms, structures, and apparatuses of Western linguistic codes that determine, produce, and maintain the ultimate (un)knowability of the past. This paper will examine all these and how the elliptical tendency of language surfaces the psychological disfigurement of the characters within the form of linguistic codes revealing the metaphorical tendency in Jazz to manifest its own reflective construction (and self-conscious deconstruction).展开更多
Background: Glenohumeral internal rotation deficit (GIRD) is a risk factor for shoulder and elbow injury in baseball players. Although this evidence forms a basis for recommending stretching, clinical measures of i...Background: Glenohumeral internal rotation deficit (GIRD) is a risk factor for shoulder and elbow injury in baseball players. Although this evidence forms a basis for recommending stretching, clinical measures of internal rotation range of motion (ROM) do not differentiate if GIRD is due to muscular, capsuloligamentous, or osseous factors. Understanding the contributions of these structures to GIRD is important for the development of targeted interventions. We hypothesize that the osseous component will have the greatest relative contribution to GIRD, followed by muscle stiffness and posterior capsule thickness. Methods: Internal rotation ROM, muscle stiffness (teres minor, infraspinatus, and posterior deltoid), posterior capsule thickness, and humeral retrotorsion were evaluated on 156 baseball players. A side-to-side difference was calculated for each variable. Variables were entered into a multivariable linear regression to determine the significant predictors of GIRD. Results: The regression model was statistically significant (R2 = 0.134, F(1, 156) = 24.0, p 〈 0.01) with only humeral retrotorsion difference remaining as a significant predictor (β = -0.243, t156 = -4.9, p 〈 0.01). A greater humeral retrotorsion side-to-side difference was associated with more GIRD. Conclusion: Humeral retrotorsion accounted for 13.3% of the variance in GIRD. The stiffness of the superficial shoulder muscles and capsular thickness, as measured in this study, were not predictors of GIRD. Factors not assessed in this study, such as deeper muscle stiffness, capsule/ ligament laxity, and neuromuscular regulation of muscle stiffness may also contribute to GIRD. Since it is the largest contributor to GIRD, causes of changes in humeral retrotorsion need to be identified. The osseous component only accounted for 13.3% of the variance in GIRD, indicating a large contribution from soft tissues factors that were not addressed in this study. These factors need to be identified to develop evidence-based evaluations and intervention programs to decrease the risk of injury in baseball players.展开更多
Objective:The purpose of this study was to analyze the clinical disadvantages of non-standard surgical treatment for parotid gland cancer and probe the re-operative indication following non-standard surgical treatment...Objective:The purpose of this study was to analyze the clinical disadvantages of non-standard surgical treatment for parotid gland cancer and probe the re-operative indication following non-standard surgical treatment.Methods: Data of 58 cases suffered parotid gland cancer who received non-standard operation at other hospital and received re-operation in tumor hospital of Ganzhou from June 1998 to October 2010 were retrospectively reviewed.Results: In all cases,parotid gland cancer were residual in 46 cases,the facial nerve remaining rate was 81.0% (47/58),facial nerve branches injury rate was 3.5% (2/58),facial nerve partial resection rate was 8.6% (5/58) and total resection rate was 6.9% (4/58).The sensitivity of residual tumor was 83.3%,scanned by contrast-enhanced CT and the CT positive predictive value was 86.9%. Conclusion: Consideration of the higher residual tumor rate in patients who received non-standard operations,the re-operations were necessary.Contrast-enhanced CT positive predictive value was high for residual tumor and it was important for re-operation.展开更多
In order to study the effects of wet compression on a transonic compressor,a full 3-D steady numerical simulation was carried out under varying conditions.Different injected water flow rates and droplet diameters were...In order to study the effects of wet compression on a transonic compressor,a full 3-D steady numerical simulation was carried out under varying conditions.Different injected water flow rates and droplet diameters were considered.The effect of wet compression on the shock,separated flow,pressure ratio,and efficiency was investigated.Additionally,the effect of wet compression on the tip clearance when the compressor runs in the near-stall and stall situations was emphasized.Analysis of the results shows that the range of stable operation is extended,and that the pressure ratio and inlet air flow rate are also increased at the near-stall point.In addition,it seems that there is an optimum size of the droplet diameter.展开更多
An air-gun source is the most commonly used excitation method in off shore seismic exploration.The excitation characteristics of an air-gun source aff ect seismic data quality.Far-field wavelet simulation is an import...An air-gun source is the most commonly used excitation method in off shore seismic exploration.The excitation characteristics of an air-gun source aff ect seismic data quality.Far-field wavelet simulation is an important approach to study these characteristics.Compared to the measured wavelet,far-field wavelet simulation based on a traditional bubble-motion equation and ideal gas wavelet model has some disadvantages,such as a greater amplitude and smaller pulse attenuation velocity.Here,we start from the linear acoustic wave equation in the spherical coordinate system to deduce an improved,simpler bubble-motion equation and develop a Van der Waals gas wavelet model based on this equation.Unlike the existing methods,our method considers the high-pressure environment during actual excitation,heat exchange between the bubble and outside water,and change in the air fl ow at the muzzle.The results show that the far-fi eld wavelet simulated using this model is closer to the measured wavelet than that of the ideal gas wavelet model.At the same time,our method has a more succinct equation and a higher calculation effi ciency.展开更多
Hannah Arendt, the new film by the German director Margarethe Von Trotta, does not seem just like another trying to represent philosophy through the classic cinematic storytelling. It builds instead a perfect dialogue...Hannah Arendt, the new film by the German director Margarethe Von Trotta, does not seem just like another trying to represent philosophy through the classic cinematic storytelling. It builds instead a perfect dialogue between these two practices that never encroach each other: There is not any doctrine that prevents cinema's freedom to create images and any philosophy claim that forces cinema to find in images an alternative way of expression. Von Trotta leaves any biopic form and stages a harmonic building where cinema fulfills philosophy and philosophy fulfills cinema. In this way she gets an outright practical exhibition of a theory, the "banality of evil". We want to comprehend the reasons of this perfect building analyzing this film, its characters with their acts, all the images their montage, and editing, everything that supports the Arendt's philosophical notion. We work on the film with the philosophical categories created by Gilles Deleuze to study the history of cinema in two essays, Image-mouvement and Image-time. In this way we can unfold how Margarethe Von Trotta represents a theory through images, without any word as intermediary展开更多
Objective: The aim of the research was to study the clinical feasibility of autograft-prosthesis composite for aggressive giant call tumor of bone around knee. Methods: Seven patients (5 males and 2 females, the me...Objective: The aim of the research was to study the clinical feasibility of autograft-prosthesis composite for aggressive giant call tumor of bone around knee. Methods: Seven patients (5 males and 2 females, the mean age of 30.5 years old) with giant cell tumor of bone around knee underwent tumor resection and reconstructed with autograft-prosthesis composites since January 2006. Five lesions located at the distal femur and 2 at the proximal tibia. There were 3 patients with primary tumor and 4 with recurrent. Three patients with pathological fracture and all patients were of Campanacci Ⅲ. Results: All patients were done follow-up from 12 to 36 months. No recurrence, metastasis, and prosthesis loosening were found. The mean healing time between autograft and host bone was 5 months. The mean motion range of affected knee were 90° (70°-110°). Conclusion: Our data documented the clinical feasibility of autograft-prosthesis composite for giant cell tumor of bone around knee which should be performed tumor resection and reconstructed with prosthesis. The long-term outcomes remain to be further proven.展开更多
In order to eliminate the drawbacks of conventional force feedback gloves, a new type of master fin- ger has been developed. By utilizing three "four-bar mechanism joint" in series and wire coupling mecha- nism, the...In order to eliminate the drawbacks of conventional force feedback gloves, a new type of master fin- ger has been developed. By utilizing three "four-bar mechanism joint" in series and wire coupling mecha- nism, the master finger transmission ratio is kept exactly 1:1.4:1 in the whole movement range and it can make active motions in both extension and flexion directions. Additionally, to assure faster data transmission and near zero delay in the master-slave operation, a digital signal processing/field programmable gate array (DSP/FPGA-FPGA) structure with 200μs cycle time is designed. The operating modes of the master finger can be contact or non-contact, which depends on the motion states of a slave finger, free motion or constrained motion. The position control employed in non-contact mode ensures unconstrained motion and the force control adopted in contact mode guarantees natural contact sensation. To evaluate the performances of the master finger, an experiment between the master finger and a DLR/HTT dexterous finger is conducted. The results demonstrate that this new type master finger can augment telepresence.展开更多
Gravitational contributions to the running of gauge couplings are calculated by using different regularizationschemes.As the β function concerns counter-terms of dimension four, only quadratic divergences from the gr...Gravitational contributions to the running of gauge couplings are calculated by using different regularizationschemes.As the β function concerns counter-terms of dimension four, only quadratic divergences from the gravitationalcontributions need to be investigated.A consistent result is obtained by using a symmetry-preserving loop regularizationwith string-mode regulators which can appropriately treat the quadratic divergences and preserve non-abelian gaugesymmetry.The harmonic gauge condition for gravity is used in both diagrammatical and background field calculations,the resulting gravitational corrections to the β function are found to be nonzero, which is different from previous resultspresented in the existing literatures.展开更多
Ignition delay of syngas is an important factor that affects stable operation of combustor and adding diluents to syngas can reduce NO_x emission.This paper used H_2O,CO_2 and N_2 as diluents and calculated ignition d...Ignition delay of syngas is an important factor that affects stable operation of combustor and adding diluents to syngas can reduce NO_x emission.This paper used H_2O,CO_2 and N_2 as diluents and calculated ignition delay of syngas in temperature range of 900-1400 K and at pressures of 10 and 30 atm respectively.In high temperature range,comparing with N_2 dilution,adding H_2O and CO_2 can significantly inhibit autoignition of syngas because they have higher collision efficiencies in reaction H + O_2(+ M) = HO_2(+ M).As for low temperature conditions,adding H_2O can increase reactivity of syngas,especially under high pressure,because of its high collision efficiency in reaction H_2O_2(+ M) = 2OH(+ M).Comparing with different dilution rates shows that for syngas and operating conditions in this paper,adding N_2 mainly influences temperature rising process of syngas combustion,thus inhibiting reactivity of syngas.In addition,this paper calculated ignition delay of syngas at different equivalence ratios(φ= 0.5,1.0).Higher equivalence ratio(φ≤1) means that less air(especially N_2) needs to be heated,thus promoting ignition of syngas,展开更多
The main technical backgrounds and requirements are introduced with regard to earthquake ground motion design parameters in several domestic and American standards,codes and guides involved in the seismic analysis and...The main technical backgrounds and requirements are introduced with regard to earthquake ground motion design parameters in several domestic and American standards,codes and guides involved in the seismic analysis and design activities of nuclear power plants in China.Based on the research results from site seismic safety evaluation of domestic nuclear power plant projects in the last years,characteristics and differences of site specific design spectra are analyzed in comparison with standard response spectra,and the suitability of standard response spectra for domestic nuclear power plant projects is discussed.展开更多
The article presents the legal and economic issues connected with the formation and operation of Polish agricultural cooperatives. Additionally, it shows a brief history of cooperative development on Polish lands and ...The article presents the legal and economic issues connected with the formation and operation of Polish agricultural cooperatives. Additionally, it shows a brief history of cooperative development on Polish lands and statistical data on agriculture and cooperatives. Most attention is given to dairy cooperatives, cooperative groups of agricultural producers and agricultural production cooperatives. These types of cooperatives are the most popular in Polish agriculture. The fundamental law regulating the issue of cooperatives in Poland is the Cooperative Law Act of September 16, 1982. Other laws, however, also have a big influence on the business activity of agricultural cooperatives, especially the EU legal regulations. Poland membership in the European Union has created new possibilities of development for the cooperative movement.展开更多
文摘The canonical quantum teleportation of two-particle arbitrary state is realized by means of phase operator and number operator. The maximally entangled eigenstates between the difference of phase operators and the sum of number operators are considered as the quantum channels. In contrast to the standard quantum teleportation, the different unitary local operation of canonical teleportation can be simplified by a general expression.
文摘A novel charge exchanging compensation (CEC) technique is proposed for a wideband sample-and-hold (S/H) circuit applied in an IF sampling ADC. The CEC technique compensates the sampling bandwidth by eliminating the impact from finite on-resistance of the sampling switch, and avoids increasing clock feedthrough and charge injection. Meanwhile, a low power two stage OTA with a class AB output stage is designed to provide the S/H a 3Vp-p input range under 1.8V power. The S/H achieves a 94dB spurious-free dynamic range for a 200MHz input signal at a 100Ms/s sample rate and consumes only 26mW with a 5.5pF load.
基金Project(2002AA422260) supported by the National High Technology Research and Development Program of ChinaProject(2011-6) supported by CAST-HIT Joint Program,ChinaProject supported by Harbin Institute of Technology (HIT) Overseas Talents Introduction Program,China
文摘A novel 6-PSS flexible parallel mechanism was presented,which employed wide-range flexure hinges as passive joints.The proposed mechanism features micron level positioning accuracy over cubic centimeter scale workspace.A three-layer back-propagation(BP) neural network was utilized to the kinematics analysis,in which learning samples containing 1 280 groups of data based on stiffness-matrix method were used to train the BP model.The kinematics performance was accurately calculated by using the constructed BP model with 19 hidden nodes.Compared with the stiffness model,the simulation and numerical results validate that BP model can achieve millisecond level computation time and micron level calculation accuracy.The concept and approach outlined can be extended to a variety of applications.
文摘Throughout Jazz (2004), Morrison revises language and stakes a generic revolution within her linguistic one. Problematising language, she interrogates its role by disrupting all metaphoric operation and normative operations of traditional Westem narratology, challenging ontological distinction, and undermining a novelistic claim of/for reality. Morrison creates the novel as a parody of itself. As a metafictional object, she (re)visions the fiction with multiple agendas--a means to interrogate the reality of its constitution and to implicate the political consequences inherent in that constitutional process of construction. By creating a series of antagonisms, oppositions, contradictions, equivalences, and intertextualities, Morrison transforms (and transmutes) novelistic "hostility" into a generic "trauma" simultaneously rendering it as realistic experience, historic event, personal story, collective memory, narrative device, and psychological phenomena. Exposing trauma by virtue of its linguistic symptoms, Morrison draws attention to the underlying mechanisms, structures, and apparatuses of Western linguistic codes that determine, produce, and maintain the ultimate (un)knowability of the past. This paper will examine all these and how the elliptical tendency of language surfaces the psychological disfigurement of the characters within the form of linguistic codes revealing the metaphorical tendency in Jazz to manifest its own reflective construction (and self-conscious deconstruction).
文摘Background: Glenohumeral internal rotation deficit (GIRD) is a risk factor for shoulder and elbow injury in baseball players. Although this evidence forms a basis for recommending stretching, clinical measures of internal rotation range of motion (ROM) do not differentiate if GIRD is due to muscular, capsuloligamentous, or osseous factors. Understanding the contributions of these structures to GIRD is important for the development of targeted interventions. We hypothesize that the osseous component will have the greatest relative contribution to GIRD, followed by muscle stiffness and posterior capsule thickness. Methods: Internal rotation ROM, muscle stiffness (teres minor, infraspinatus, and posterior deltoid), posterior capsule thickness, and humeral retrotorsion were evaluated on 156 baseball players. A side-to-side difference was calculated for each variable. Variables were entered into a multivariable linear regression to determine the significant predictors of GIRD. Results: The regression model was statistically significant (R2 = 0.134, F(1, 156) = 24.0, p 〈 0.01) with only humeral retrotorsion difference remaining as a significant predictor (β = -0.243, t156 = -4.9, p 〈 0.01). A greater humeral retrotorsion side-to-side difference was associated with more GIRD. Conclusion: Humeral retrotorsion accounted for 13.3% of the variance in GIRD. The stiffness of the superficial shoulder muscles and capsular thickness, as measured in this study, were not predictors of GIRD. Factors not assessed in this study, such as deeper muscle stiffness, capsule/ ligament laxity, and neuromuscular regulation of muscle stiffness may also contribute to GIRD. Since it is the largest contributor to GIRD, causes of changes in humeral retrotorsion need to be identified. The osseous component only accounted for 13.3% of the variance in GIRD, indicating a large contribution from soft tissues factors that were not addressed in this study. These factors need to be identified to develop evidence-based evaluations and intervention programs to decrease the risk of injury in baseball players.
文摘Objective:The purpose of this study was to analyze the clinical disadvantages of non-standard surgical treatment for parotid gland cancer and probe the re-operative indication following non-standard surgical treatment.Methods: Data of 58 cases suffered parotid gland cancer who received non-standard operation at other hospital and received re-operation in tumor hospital of Ganzhou from June 1998 to October 2010 were retrospectively reviewed.Results: In all cases,parotid gland cancer were residual in 46 cases,the facial nerve remaining rate was 81.0% (47/58),facial nerve branches injury rate was 3.5% (2/58),facial nerve partial resection rate was 8.6% (5/58) and total resection rate was 6.9% (4/58).The sensitivity of residual tumor was 83.3%,scanned by contrast-enhanced CT and the CT positive predictive value was 86.9%. Conclusion: Consideration of the higher residual tumor rate in patients who received non-standard operations,the re-operations were necessary.Contrast-enhanced CT positive predictive value was high for residual tumor and it was important for re-operation.
基金Supported by the National Natural Science Foundation of China under Grant No.50776021
文摘In order to study the effects of wet compression on a transonic compressor,a full 3-D steady numerical simulation was carried out under varying conditions.Different injected water flow rates and droplet diameters were considered.The effect of wet compression on the shock,separated flow,pressure ratio,and efficiency was investigated.Additionally,the effect of wet compression on the tip clearance when the compressor runs in the near-stall and stall situations was emphasized.Analysis of the results shows that the range of stable operation is extended,and that the pressure ratio and inlet air flow rate are also increased at the near-stall point.In addition,it seems that there is an optimum size of the droplet diameter.
基金supported by National Natural Science Foundation of China (No. 41674118)
文摘An air-gun source is the most commonly used excitation method in off shore seismic exploration.The excitation characteristics of an air-gun source aff ect seismic data quality.Far-field wavelet simulation is an important approach to study these characteristics.Compared to the measured wavelet,far-field wavelet simulation based on a traditional bubble-motion equation and ideal gas wavelet model has some disadvantages,such as a greater amplitude and smaller pulse attenuation velocity.Here,we start from the linear acoustic wave equation in the spherical coordinate system to deduce an improved,simpler bubble-motion equation and develop a Van der Waals gas wavelet model based on this equation.Unlike the existing methods,our method considers the high-pressure environment during actual excitation,heat exchange between the bubble and outside water,and change in the air fl ow at the muzzle.The results show that the far-fi eld wavelet simulated using this model is closer to the measured wavelet than that of the ideal gas wavelet model.At the same time,our method has a more succinct equation and a higher calculation effi ciency.
文摘Hannah Arendt, the new film by the German director Margarethe Von Trotta, does not seem just like another trying to represent philosophy through the classic cinematic storytelling. It builds instead a perfect dialogue between these two practices that never encroach each other: There is not any doctrine that prevents cinema's freedom to create images and any philosophy claim that forces cinema to find in images an alternative way of expression. Von Trotta leaves any biopic form and stages a harmonic building where cinema fulfills philosophy and philosophy fulfills cinema. In this way she gets an outright practical exhibition of a theory, the "banality of evil". We want to comprehend the reasons of this perfect building analyzing this film, its characters with their acts, all the images their montage, and editing, everything that supports the Arendt's philosophical notion. We work on the film with the philosophical categories created by Gilles Deleuze to study the history of cinema in two essays, Image-mouvement and Image-time. In this way we can unfold how Margarethe Von Trotta represents a theory through images, without any word as intermediary
文摘Objective: The aim of the research was to study the clinical feasibility of autograft-prosthesis composite for aggressive giant call tumor of bone around knee. Methods: Seven patients (5 males and 2 females, the mean age of 30.5 years old) with giant cell tumor of bone around knee underwent tumor resection and reconstructed with autograft-prosthesis composites since January 2006. Five lesions located at the distal femur and 2 at the proximal tibia. There were 3 patients with primary tumor and 4 with recurrent. Three patients with pathological fracture and all patients were of Campanacci Ⅲ. Results: All patients were done follow-up from 12 to 36 months. No recurrence, metastasis, and prosthesis loosening were found. The mean healing time between autograft and host bone was 5 months. The mean motion range of affected knee were 90° (70°-110°). Conclusion: Our data documented the clinical feasibility of autograft-prosthesis composite for giant cell tumor of bone around knee which should be performed tumor resection and reconstructed with prosthesis. The long-term outcomes remain to be further proven.
文摘In order to eliminate the drawbacks of conventional force feedback gloves, a new type of master fin- ger has been developed. By utilizing three "four-bar mechanism joint" in series and wire coupling mecha- nism, the master finger transmission ratio is kept exactly 1:1.4:1 in the whole movement range and it can make active motions in both extension and flexion directions. Additionally, to assure faster data transmission and near zero delay in the master-slave operation, a digital signal processing/field programmable gate array (DSP/FPGA-FPGA) structure with 200μs cycle time is designed. The operating modes of the master finger can be contact or non-contact, which depends on the motion states of a slave finger, free motion or constrained motion. The position control employed in non-contact mode ensures unconstrained motion and the force control adopted in contact mode guarantees natural contact sensation. To evaluate the performances of the master finger, an experiment between the master finger and a DLR/HTT dexterous finger is conducted. The results demonstrate that this new type master finger can augment telepresence.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10821504,10491306,10975170 the Project of Knowledge Innovation Program of Chinese Academy of Science
文摘Gravitational contributions to the running of gauge couplings are calculated by using different regularizationschemes.As the β function concerns counter-terms of dimension four, only quadratic divergences from the gravitationalcontributions need to be investigated.A consistent result is obtained by using a symmetry-preserving loop regularizationwith string-mode regulators which can appropriately treat the quadratic divergences and preserve non-abelian gaugesymmetry.The harmonic gauge condition for gravity is used in both diagrammatical and background field calculations,the resulting gravitational corrections to the β function are found to be nonzero, which is different from previous resultspresented in the existing literatures.
基金Supported by National High Technology Research and Development Program of China(2009AA05Z310)
文摘Ignition delay of syngas is an important factor that affects stable operation of combustor and adding diluents to syngas can reduce NO_x emission.This paper used H_2O,CO_2 and N_2 as diluents and calculated ignition delay of syngas in temperature range of 900-1400 K and at pressures of 10 and 30 atm respectively.In high temperature range,comparing with N_2 dilution,adding H_2O and CO_2 can significantly inhibit autoignition of syngas because they have higher collision efficiencies in reaction H + O_2(+ M) = HO_2(+ M).As for low temperature conditions,adding H_2O can increase reactivity of syngas,especially under high pressure,because of its high collision efficiency in reaction H_2O_2(+ M) = 2OH(+ M).Comparing with different dilution rates shows that for syngas and operating conditions in this paper,adding N_2 mainly influences temperature rising process of syngas combustion,thus inhibiting reactivity of syngas.In addition,this paper calculated ignition delay of syngas at different equivalence ratios(φ= 0.5,1.0).Higher equivalence ratio(φ≤1) means that less air(especially N_2) needs to be heated,thus promoting ignition of syngas,
基金funded by the Basic Science Research Foundation of IEM(Grant No.2006A02)the National Natural Sciences Foundation of China (90715038)
文摘The main technical backgrounds and requirements are introduced with regard to earthquake ground motion design parameters in several domestic and American standards,codes and guides involved in the seismic analysis and design activities of nuclear power plants in China.Based on the research results from site seismic safety evaluation of domestic nuclear power plant projects in the last years,characteristics and differences of site specific design spectra are analyzed in comparison with standard response spectra,and the suitability of standard response spectra for domestic nuclear power plant projects is discussed.
文摘The article presents the legal and economic issues connected with the formation and operation of Polish agricultural cooperatives. Additionally, it shows a brief history of cooperative development on Polish lands and statistical data on agriculture and cooperatives. Most attention is given to dairy cooperatives, cooperative groups of agricultural producers and agricultural production cooperatives. These types of cooperatives are the most popular in Polish agriculture. The fundamental law regulating the issue of cooperatives in Poland is the Cooperative Law Act of September 16, 1982. Other laws, however, also have a big influence on the business activity of agricultural cooperatives, especially the EU legal regulations. Poland membership in the European Union has created new possibilities of development for the cooperative movement.