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Comparison on Winter Wheat Yield Estimating Models Based on Radarsat-2 and HJ Satellite in Huaihe River Region 被引量:1
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作者 范伟 陈磊 +2 位作者 陈娟 闫洪凯 刘韬 《Agricultural Science & Technology》 CAS 2016年第4期1019-1023,共5页
The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model... The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model. With Shou County and Huaiyuan County of Anhui Province as the experimental fields of winter wheat producing areas, the linear winter wheat yield estimating models were established by adopting backscattering coefficient and Normalized Difference Vegetation Index(NDVI) based on images from the synthetic aperture radar(SAR)—RDARSAT-2 and HJ satellite photographed in mid-April and early May, 2014, and then comparisons were conducted on the accuracy of the yield estimating models. The accuracies of the yield estimating models established using co-polarized(HH) and cross-polarized(HV) modes of SAR in Jiangou Town, Shou County were 68.37% and 74.01%, respectively, while the accuracies in Longkang Town, Huaiyuan County were 63.10%and 69.10%, respectively. Accuracies of yield estimating models established by HJ satellite data were 69.52% and 66.43% in Shou County and Huaiyuan County, respectively. Accuracies of winter yield estimating model based on HJ satellite data and that based on SAR were closed, and the yield difference of winter wheat in the lodging region was analyzed in detail. The model results laid the foundation and accumulated experience for the verification, parameters correction and promotion of the winter wheat yield estimating model. 展开更多
关键词 Winter wheat yield estimating model Synthetic aperture radar RADARSAT-2 HJ satellite Model comparison
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Parameter Extraction for 2-π Equivalent Circuit Model of RF CMOS Spiral Inductors 被引量:1
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作者 高巍 余志平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期667-673,共7页
A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experiment... A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experimental data. The extraction strategy is straightforward and can be easily implemented as a CAD tool to model spiral inductors. The resulting circuit models will be very useful for RF circuit designers. 展开更多
关键词 2 compact model parameters extraction RF CMOS spiral inductors
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Edaravone protects PC12 cells from ischemic-like injury via attenuating the damage to mitochondria 被引量:16
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作者 SONG Ying LI Meng +1 位作者 LI Ji-cheng WEI Er-qing 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第9期749-756,共8页
Background: Edaravone had been validated to effectively protect against ischemic injuries. In this study, we investigated the protective effect of edaravone by observing the effects on anti-apoptosis, regulation of B... Background: Edaravone had been validated to effectively protect against ischemic injuries. In this study, we investigated the protective effect of edaravone by observing the effects on anti-apoptosis, regulation of Bcl-2/Bax protein expression and recovering from damage to mitochondria after OGD (oxygen-glucose deprivation)-reperfusion. Methods: Viability of PC 12 cells which were injured at different time of OGD injury, was quantified by measuring MTT (2-(4,5-dimethylthia-zol-2-yl)-2,5-diphenyltetrazolium bromide) staining. In addition, PC 12 cells' viability was also quantified after their preincubation in different concentration of edaravone for 30 min followed by (OGD). Furthermore, apoptotic population of PC 12 cells that reinsulted from OGD-reperfusion with or without preincubation with edaravone was determined by flow cytometer analysis, electron microscope and Hoechst/Pl staining. Finally, change of Bcl-2/Bax protein expression was detected by Western blot. Results: (1) The viability of PC12 cells decreased with time (1-12 h) after OGD. We regarded the model of OGD 2 h, then replacing DMEM (Dulbecco's Modified Eagle's Medium) for another 24 h as an OGD-reperfusion in this research. Furthermore, most PC 12 cells were in the state of apoptosis after OGD-reperfusion. (2) The viability of PC 12 cells preincubated with edaravone at high concentrations (1, 0.1, 0.01 μmol/L) increased significantly with edaravone protecting PC 12 cells from apoptosis after OGD-reperfusion injury. (3) Furthermore, edaravone attenuates the damage of OGD-reperfusion on mitochondria and regulated Bcl-2/Bax protein imbalance expression after OGD-reperfusion. Conclusion: Neuroprotective effects of edaravone on ischemic or other brain injuries may be partly mediated through inhibition of Bcl-2/Bax apoptotic pathways by recovering from the damage of mitochondria. 展开更多
关键词 EDARAVONE lschemia Apoptosis Rat pheochromocytoma (PC 12 cells MITOCHONDRIA Bax Bcl-2 Oxygen-glucose deprivation (OGD)
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Global Existence in H^2 for a 1-d Non-monotone Fluid 被引量:1
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作者 吴中林 徐娟娟 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期296-304,共9页
In this paper, we prove the existence in H+^2, an incomplete metric subspace of H^2×H^2×H^2, of global solutions to the system for a one-dimensional non-monotone fluid in bounded domainΩ=(0,1). The resul... In this paper, we prove the existence in H+^2, an incomplete metric subspace of H^2×H^2×H^2, of global solutions to the system for a one-dimensional non-monotone fluid in bounded domainΩ=(0,1). The results in this paper have improved those previously related results. 展开更多
关键词 non-monotone fluid mixed free boundary model global existence priori estimates
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Non-linear 2-DOF model and centre manifold theory to study limit cycle oscillations caused by drum-brake judder
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作者 周明刚 《Journal of Chongqing University》 CAS 2007年第1期55-62,共8页
This paper presents the research on the laws of systematic-parameter dependent variation in the vibration amplitude of drum-brake limit cycle oscillations (LCO). We established a two-degree non-linear dynamic model to... This paper presents the research on the laws of systematic-parameter dependent variation in the vibration amplitude of drum-brake limit cycle oscillations (LCO). We established a two-degree non-linear dynamic model to describe the low-frequency vibration of the drum brake, applied the centre manifold theory to simplify the system, and obtained the LCO amplitude by calculating the normal form of the simplified system at the Hopf bifurcation point. It is indicated that when the friction coefficient is smaller than the friction coefficient at the bifurcation point, the amplitude decreases; whereas with a friction coefficient larger than the friction coefficient of bifurcation point, LCO occurs. The results suggest that it is applicable to suppress the LCO amplitude by changing systematic parameters, and thus improve the safety and ride comfort when applying brake. These findings can be applied to guiding the design of drum brakes. 展开更多
关键词 drum brake NON-LINEAR BIFURCATION limit cycle oscillation
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Oscillating Solitons for (2+1)-Dimensional Nonlinear Models 被引量:2
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作者 Naranmandula Tubuxin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期282-286,共5页
Using extended homogeneous balance method and variable separation hypothesis, we found new variable separation solutions with three arbitrary functions of the (2+1)-dimensional dispersive long-wave equations, Based... Using extended homogeneous balance method and variable separation hypothesis, we found new variable separation solutions with three arbitrary functions of the (2+1)-dimensional dispersive long-wave equations, Based on derived solutions, we revealed abundant oscillating solitons such as dromion, multi-dromion, solitoff, solitary waves, and so on, by selecting appropriate functions. 展开更多
关键词 oscillating soliton 2+1)-dimensional system extended homogeneous balance method
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Validation of the relationship consciousness of Japanese Patients with type 2 diabetes scale
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作者 Miki Koike Michiko Inagaki +4 位作者 Keiko Tasaki Kiyoko Matsui Tomomi Horiguchi Azusa Oda Tantut Susanto 《International Journal of Nursing Sciences》 CSCD 2019年第1期31-37,共7页
Objectives:The management of type 2 diabetes mellitus can be improved for individuals by developing relationships with other patients with diabetes.We created the Relationship Consciousness of Japanese Patients with T... Objectives:The management of type 2 diabetes mellitus can be improved for individuals by developing relationships with other patients with diabetes.We created the Relationship Consciousness of Japanese Patients with Type 2 Diabetes Mellitus scale to measure the relationship consciousness of type 2 diabetes mellitus patients for other patients based on the Health Belief Model.Methods:This was a cross-sectional study of Japanese patients with type 2 diabetes mellitus(n-289).Data were analyzed via exploratory factor analyses,reliability tests,concurrent validity.Results:The final scale obtained for the Relationship Consciousness of Japanese Patients with Type 2 Diabetes Mellitus scale comprised a six-factor structure with 36 items.All 36 items had a Cronbach'sαcoefficient of 0.893 and explained 59.38%of the total variance.The scale was significantly correlated with a related reciprocity consciousness scale.Conclusions:The Relationship Consciousness of Japanese Patients with Type 2 Diabetes Mellitus scale may be an important tool for nurses to assess the relationship consciousness of patients with type 2 diabetes mellitus.In addition,by understanding patients'relationship consciousness for others who share their disease,nurses can begin to recommend ways to establish relationships between patients that suit patients'particular relationship.consciousness levels and to provide better care in their clinical practice. 展开更多
关键词 CONSCIOUSNESS Diabetes Mellitus Type 2 Health belief Model RELATIONSHIP
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Development of a Loop-Mediated Isothermal Amplification Assay for Porcine Circovirus Type 2 被引量:3
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作者 Ye-bing Liu Lei Zhang +2 位作者 Qin-hong Xue Yi-bao Ning Zhi-gang Zhang 《Virologica Sinica》 SCIE CAS CSCD 2011年第3期214-220,共7页
In this study, the loop-mediated isothermal amplification (LAMP) method was used to develop a rapid and simple detection system for porcine circovirus type 2 (PCV2). According to the PCV2 sequences published in GenBan... In this study, the loop-mediated isothermal amplification (LAMP) method was used to develop a rapid and simple detection system for porcine circovirus type 2 (PCV2). According to the PCV2 sequences published in GenBank, multiple LAMP primers were designed targeting conserved sequences of PCV2. Using the DNA extracted from PCV2 isolates HUN-09 and SD-09 as the template, LAMP reactions in a PCV2 LAMP system was performed, the amplification products were detected by adding SYBR Green I and could be observed directly by the naked eye. The results showed highly-efficient and specific amplification in 30 min at 63°C with a LAMP real-time turbidimeter. Furthermore, PCV2 DNA templates, with a detection limit of 5.5×10-5 ng of nucleic acid, indicated that this assay was highly sensitive. The results obtained with the naked eye after SYBR Green I staining were consistent with those detected by the real-time turbidimeter, showing the potential simplicity of interpretation of the assay results. The LAMP assay appeared to have greater accuracy than PCR and virus isolation for the analysis of 18 clinical samples. In addition it offers higher specificity and sensitivity, shorter reaction times and simpler procedures than the currently available methods of PCV2 detection. It is therefore a promising tool for the effective and efficient detection of PCV2. 展开更多
关键词 Porcine circovirus type 2 (PCV2 Loop-mediated isothermal amplification (LAMP) Virus detection
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Adaptive control using interval Type-2 fuzzy logic for uncertain nonlinear systems 被引量:5
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作者 周海波 应浩 段吉安 《Journal of Central South University》 SCIE EI CAS 2011年第3期760-766,共7页
A new adaptive Type-2 (T2) fuzzy controller was developed and its potential performance advantage over adaptive Type-1 (T1) fuzzy control was also quantified in computer simulation. Base on the Lyapunov method, th... A new adaptive Type-2 (T2) fuzzy controller was developed and its potential performance advantage over adaptive Type-1 (T1) fuzzy control was also quantified in computer simulation. Base on the Lyapunov method, the adaptive laws with guaranteed system stability and convergence were developed. The controller updates its parameters online using the laws to control a system and tracks its output command trajectory. The simulation study involving the popular inverted pendulum control problem shows theoretically predicted system stability and good tracking performance. And the comparison simulation experiments subjected to white noige or step disturbance indicate that the T2 controller is better than the T1 controller by 0--18%, depending on the experiment condition and performance measure. 展开更多
关键词 Type-2 fuzzy systems adaptive fuzzy control nonlinear systems stability
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Quark-Antiquark and Diquark Condensates in Vacuum in a 2D Two-Flavor Gross-Neveu Model
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作者 ZHOU Bang-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期520-524,共5页
The analysis based on the renormalized effective potential indicates that, similar to in the 4D two-flavor Nambu-Jona-Lasinio (NJL) model, in a 2D two-flavor Gross-Neveu model, the interplay between the quark-antiqu... The analysis based on the renormalized effective potential indicates that, similar to in the 4D two-flavor Nambu-Jona-Lasinio (NJL) model, in a 2D two-flavor Gross-Neveu model, the interplay between the quark-antiquark and the diquark ,condensates in vacuum also depends on Gs/Hs, the ratio of the coupling constants in scalar quarkantiquark and scalar diquark channel. Only the pure quark-antiquark condensates exist if Gs/Hs 〉 2/3, which is just the ratio of the color numbers of the quarks participating in the diquark and quark-antiquark condensates. The two condensates will coexist if 0 〈 Gs/Hs 〈 2/3. However, different from the 4D NJL model, the pure diquark condensates arise only at Gs/Hs = 0 and are not in a possibly finite region of Gs/Hs below 2/3. 展开更多
关键词 2D Gross-Neveu model quark-antiquark and diquark condensates effective potential RENORMALIZATION mean-field approximation
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Reveal the nature of particle size effect for CO_(2) reduction over Pd and Au 被引量:1
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作者 Piaoping Yang Lulu Li +1 位作者 Zhi-Jian Zhao Jinlong Gong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第5期817-823,共7页
Small cluster and periodic surface models with low coverages of intermediates are frequently employed to investigate reaction mechanisms and identify active sites on nanoparticles(NPs)in density functional theory(DFT)... Small cluster and periodic surface models with low coverages of intermediates are frequently employed to investigate reaction mechanisms and identify active sites on nanoparticles(NPs)in density functional theory(DFT)studies.However,diverse active sites on NPs cannot be sufficiently represented by these simple models,hampering the in-depth insights into the catalytic behavior of NPs.This paper describes the crucial roles of both model and coverage effect on understanding the nature of active sites for CO_(2)reduction over Au and Pd NPs using DFT calculations.Terrace sites exhibit higher selectivity for CO than edge sites on Au NPs,which is opposite to the results on Au periodic surfaces.This contradiction reveals the computational model effect on clarifying active site properties.For Pd catalysts,the coverage effect is more significant.On bare Pd NPs and periodic surfaces,the selectivity for CO at edge sites is nearly identical to that at terrace sites,whereas edge sites display higher selectivity for CO than terrace sites in the case of high CO coverages.Through considering the more realistic models and the coverage effect,we successfully describe the size effect of Au and Pd NPs on CO selectivity.More importantly,this work reminds us of the necessity of reasonable models in DFT calculations. 展开更多
关键词 Density functional theory CO_(2)reduction Coverage effects Catalyst model Nanoparticles
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Beneficial effect of an antibody against interleukin-2 receptor (daclizumab) in an experimental model of hepatocyte xenotransplantation
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作者 Dimitrios Papagoras Apostolos Papalois +5 位作者 Alexandra Tsaroucha Dimitrios Lytras John Kyriazanos Nikoletta Giannakou Prodromos Laftsidis Constantine Simopoulos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第9期1435-1437,共3页
AIM: To investigate the use of Daclizumab (Dmab) as an immunosuppressive agent in an experimental model of hepatocyte xenotransplantation (XenoTx) in rats with fulminant hepatic failure (FHF). METHODS: Two white male ... AIM: To investigate the use of Daclizumab (Dmab) as an immunosuppressive agent in an experimental model of hepatocyte xenotransplantation (XenoTx) in rats with fulminant hepatic failure (FHF). METHODS: Two white male New Zealand rabbits were used as donors and 68 Wistar rats as recipients. FHF was induced by intravenous application of dimethylnitrosamine (DMNA). The isolated hepatocytes of the rabbits were xenotransplanted into the spleen of the rats 24 h after FHF induction. Group A (n = 13): no treatment; Group B (n = 14): FHF and XenoTx; Group C (n = 14): FHF and XenoTx and cyclosporin (CsA); Group D (n = 14): FHF and XenoTx and Dmab; Group E (n = 13): FHF and XenoTx and CsA and Dmab. The rats were followed for 15 d. RESULTS: Statistical analysis showed better survival among groups D (92.86%) and E (76.92%) compared to group A (all rats died after 72 h), group B (28.57%) or group C (71.43%), although the differences were not statistically significant. Biochemical evaluation of the liver enzymes and histology confirmed satisfactory function and engraftment, respectively. CONCLUSION: This experimental model has shown the safe, effective and beneficial use of Dmab in a xenotransplantation model of rabbit hepatocytes in rats. 展开更多
关键词 Transplantation HEPATOCYTES DACLIZUMAB CYCLOSPORIN
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Thermodynamic modeling of ZrO_(2)−CaO−TiO_(2)system
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作者 Shi-yu HE Qi-sheng FENG +4 位作者 Bao-hua DUAN Guang-yao CHEN Zhu WU Chong-he LI Xiong-gang LU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第2期696-708,共13页
The phase diagram of ZrO_(2)−CaO−TiO_(2)system was essential for the development of photocatalytic materials and refractory materials.In this work,the ZrO_(2)−CaO−TiO_(2)system was accessed by using the CALPHAD method... The phase diagram of ZrO_(2)−CaO−TiO_(2)system was essential for the development of photocatalytic materials and refractory materials.In this work,the ZrO_(2)−CaO−TiO_(2)system was accessed by using the CALPHAD method.The substitutional solution models were used to describe liquid and solid solution phases,the sub-lattice models were used to describe ternary compounds,and then the thermodynamic parameters were obtained by the least square method combined with literature experiment results.The acquired thermodynamic parameters were used to calculate the isothermal sections of the ZrO_(2)−CaO−TiO_(2)system at 1473 and 1673 K.There existed a good agreement between experimental and predicted phase relationships,the experimental points which were inconsistent with calculated results may be attributed to experimental errors and the sluggish kinetics of cations for ZrO_(2)-based materials.In order to further verify the validity of the database,the thermodynamic parameters were also used to simulate the thermodynamic properties(specific heat capacity,enthalpy,and entropy)of CaZrTi_(2)O_(7) within 5%errors.Good consistency demonstrated that the present thermodynamic database was self-consistent and credible. 展开更多
关键词 ZrO_(2)−CaO−TiO_(2)system Gibbs free energy model CALPHAD method isothermal sections
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Adsorption of 2-naphthalenesulfonic acid/sulfuric acid/sulfurous acid from aqueous solution by iron-impregnated weakly basic resin:Equilibrium and model 被引量:1
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作者 Changhai Li Dongmei Jia 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第11期1522-1526,共5页
Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the... Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the adsorption behavior of 2-naphthalenesulfonic acid(NSA), sulfuric acid and sulfurous acid from their solution at 298 K onto the novel hybrid iron impregnated D301(Fe-D301). Adsorption affinity of NSA on Fe-D301 was found to be much higher than that of sulfuric acid, while adsorption affinity of sulfuric acid was slightly higher than that of sulfurous acid. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The non-ideal competitive adsorbed model coupled with the single-solute adsorption models were used to predict the bisolute and trinary-solute competitive adsorption equilibria. The NICM coupled with the Langmuir model yields the favorable representation of the bisolute and trinary-solute competitive adsorption behavior. 展开更多
关键词 2-naphthalenesulfonic acid Hybrid iron impregnated D301 Adsorption Non-ideal competitive adsorbed model Model Equilibrium
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Dynamic Optimization of a 2-DOF Pseudo-Equatorial Tracking System
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作者 Monica Alina Ionita Catalin Alexandru 《Journal of Energy and Power Engineering》 2012年第5期713-718,共6页
The key word for the design process of the photovoltaic tracking systems is the energetic efficiency. Using the tracking system, the photovoltaic panel follows the sun and increases the collected energy, but the drivi... The key word for the design process of the photovoltaic tracking systems is the energetic efficiency. Using the tracking system, the photovoltaic panel follows the sun and increases the collected energy, but the driving motors consume a part of this energy. In these terms, the optimization of the tracking systems became an important challenge in the modem research and technology. In this paper, a strategy for the dynamic optimization of the photovoltaic tracking systems is presented. The main task in optimization is to maximize the energetic gain by increasing the incoming solar radiation and minimizing the energy consumption for tracking. This strategy is possible by developing the virtual prototype of the tracking system, which is a control loop composed by the multi-body mechanical model connected with the dynamic model of the actuators and with the controller model. In this way, it is possible to optimize the tracking mechanism, choose the appropriate actuators, and design the optimal controller. 展开更多
关键词 Photovoltaic panel optimization tracking mechanism control system virtual prototype energy balance.
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江苏地区设施葡萄常用品种需冷量研究 被引量:3
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作者 王西成 钱亚明 +2 位作者 赵密珍 吴伟民 王庆莲 《江苏农业科学》 北大核心 2013年第10期120-122,共3页
为探讨江苏省设施葡萄栽培的需冷量,分别利用0~7.2℃模型和犹他模型对10个设施葡萄常用品种的需冷量进行了估算分析。结果表明,10个葡萄品种中需冷量最高的为优无核、无核白鸡心、大粒六月紫3个品种,达757h或439.5C.u;需冷量最... 为探讨江苏省设施葡萄栽培的需冷量,分别利用0~7.2℃模型和犹他模型对10个设施葡萄常用品种的需冷量进行了估算分析。结果表明,10个葡萄品种中需冷量最高的为优无核、无核白鸡心、大粒六月紫3个品种,达757h或439.5C.u;需冷量最低的为金星无核,为497h或192C.U,其他品种均介于两者之间。 展开更多
关键词 葡萄 设施栽培 需冷量 0~7 2℃模型 犹他模型
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Single-and Two-band Transport Properties Crossover in Bi_(2)Te_(3)Based Thermoelectrics
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作者 MENG Yuting WANG Xuemei +2 位作者 ZHANG Shuxian CHEN Zhiwei PEI Yanzhong 《无机材料学报》 SCIE EI CAS 2024年第11期1283-1291,共9页
Based on Peltier effect,Bi_(2)Te_(3)-based alloy is widely used in commercial solid-state refrigeration at room temperature.The mainstream strategies for enhancing room-temperature thermoelectric performance in Bi_(2)... Based on Peltier effect,Bi_(2)Te_(3)-based alloy is widely used in commercial solid-state refrigeration at room temperature.The mainstream strategies for enhancing room-temperature thermoelectric performance in Bi_(2)Te_(3)focus on band and microstructure engineering.However,a clear understanding of the modulation of band structure and scattering through such engineering remains still challenging,because the minority carriers compensate partially the overall transport properties for the narrow-gap Bi_(2)Te_(3)at room temperature(known as the bipolar effect).The purpose of this work is to model the transport properties near and far away from the bipolar effect region for Bi_(2)Te_(3)-based thermoelectric material by a two-band model taking contributions of both majority and minority carriers into account.This is endowed by shifting the Fermi level from the conduction band to the valence band during the modeling.A large amount of data of Bi_(2)Te_(3)-based materials is collected from various studies for the comparison between experimental and predicted properties.The fundamental parameters,such as the density of states effective masses and deformation potential coefficients,of Bi_(2)Te_(3)-based materials are quantified.The analysis can help find out the impact factors(e.g.the mobility ratio between conduction and valence bands)for the improvement of thermoelectric properties for Bi_(2)Te_(3)-based alloys.This work provides a convenient tool for analyzing and predicting the transport performance even in the presence of bipolar effect,which can facilitate the development of the narrow-gap thermoelectric semiconductors. 展开更多
关键词 thermoelectric material Bi_(2)Te_(3)-based alloy two-band model narrow-gap thermoelectric semiconductor
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Aviation Accident Causation Analysis Based on Complex Network Theory 被引量:11
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作者 YUE Rentian LI Junwei HAN Meng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第4期646-655,共10页
Accident causation analysis is of great importance for accident prevention.In order to improve the aviation safety,a new analysis method of aviation accident causation based on complex network theory is proposed in th... Accident causation analysis is of great importance for accident prevention.In order to improve the aviation safety,a new analysis method of aviation accident causation based on complex network theory is proposed in this paper.Through selecting 257 accident investigation reports,45 causative factors and nine accident types are obtained by the three-level coding process of the grounded theory,and the interaction of these factors is analyzed based on the“2-4”model.Accordingly,the aviation accident causation network is constructed based on complex network theory which has scale-free characteristics and small-world properties,the characteristics of causative factors are analyzed by the topology of the network,and the key causative factors of the accidents are identified by the technique for order of preference by similarity to ideal solution(TOPSIS)method.The comparison results show that the method proposed in this paper has the advantages of independent of expert experience,quantitative analysis of accident causative factors and statistical analysis of a lot of accident data,and it has better applicability and advancement. 展开更多
关键词 aviation safety accident causation complex network theory grounded theory 2-4”model
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Carvedilol protected diabetic rat hearts via reducing oxidative stress 被引量:4
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作者 HUANG He SHAN Jiang +2 位作者 PAN Xiao-hong WANG Hui-ping QIAN Ling-bo 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第9期725-731,共7页
Oxidative stress plays a dominant role in the pathogenesis of diabetes mellitus. Bcl-2 gene has close connection with antioxidant stress destruction in many diseases including diabetes. Carvedilol, an adrenoceptor blo... Oxidative stress plays a dominant role in the pathogenesis of diabetes mellitus. Bcl-2 gene has close connection with antioxidant stress destruction in many diseases including diabetes. Carvedilol, an adrenoceptor blocker, also has antioxidant properties. To study the effect of carvedilol on the antioxidant status in diabetic hearts, we investigated carvedilol-administrated healthy and streptozotocin-induced diabetic rats. After small and large dosage carvedilol-administered for 5 weeks, hemodynamic parameters, the levels of malondialdehyde, activities of antioxidant enzymes and expression of Bcl-2 mRNA in the cardiac tissues were measured. The diabetic rats not only had cardiac disfunction, weaker activities of antioxidant enzymes, but also showed lower expression of Bcl-2. Carvedilol treatment increased activities of antioxidant enzymes and expression of Bcl-2 in healthy rats as well as diabetic rats. These results indicated that carvedilol partly improves cardiac function via its antioxidant properties in diabetic rats. 展开更多
关键词 CARVEDILOL DIABETES Oxidative stress BCL-2
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Criticality of Parasitic Disease Transmission in a Diffusive Population
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作者 HE Min-Hua ZHANG Duan-Ming +2 位作者 PAN Gui-Jun YIN Yah-Ping CHEN Zhi-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1351-1354,共4页
Through using the methods of finite-size effect and short time dynamic scaling,we study the criticalbehavior of parasitic disease spreading process in a diffusive population mediated by a static vector environment.Thr... Through using the methods of finite-size effect and short time dynamic scaling,we study the criticalbehavior of parasitic disease spreading process in a diffusive population mediated by a static vector environment.Throughcomprehensive analysis of parasitic disease spreading we find that this model presents a dynamical phase transition fromdisease-free state to endemic state with a finite population density.We determine the critical population density,abovewhich the system reaches an epidemic spreading stationary state.We also perform a scaling analysis to determine theorder parameter and critical relaxation exponents.The results show that the model does not belong to the usual directedpercolation universality class and is compatible with the class of directed percolation with diffusive and conserved fields. 展开更多
关键词 directed percolation disease spreading finite-size effect POWER-LAW
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