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环模模孔参数对颗粒饲料加工质量及肉鸡生长性能的影响 被引量:8
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作者 王昊 于纪宾 +2 位作者 于治芹 李俊 李军国 《动物营养学报》 CAS CSCD 北大核心 2017年第9期3352-3358,共7页
本试验旨在研究环模模孔参数对颗粒饲料加工质量及肉鸡生长性能的影响。通过固定模孔直径(3mm)改变模孔长径比(6∶1、8∶1、10∶1)以及固定模孔长径比(10∶1)改变模孔直径(3.0、3.5、4.0mm),生产5种不同直径及硬度的肉鸡颗粒饲料。选取... 本试验旨在研究环模模孔参数对颗粒饲料加工质量及肉鸡生长性能的影响。通过固定模孔直径(3mm)改变模孔长径比(6∶1、8∶1、10∶1)以及固定模孔长径比(10∶1)改变模孔直径(3.0、3.5、4.0mm),生产5种不同直径及硬度的肉鸡颗粒饲料。选取864只体重相近的21日龄爱拔益加(AA)肉鸡,随机分成6组,每个组8个重复,每个重复18只。Ⅰ~Ⅴ组分别饲喂模孔直径和长径比分别为3.0mm和6∶1、3.0mm和8∶1、3.0mm和10∶1、3.5mm和10∶1、4.0mm和10∶1的颗粒饲料;Ⅵ组分2阶段饲喂,22~35日龄饲喂模孔直径和长径比为3.0 mm和10∶1颗粒饲料,36~42日龄饲喂模孔直径和长径比为4.0mm和10∶1颗粒饲料。试验期21d。结果表明:1)模孔直径相同时,颗粒硬度随着模孔长径比的增加而极显著提高(P<0.01);模孔长径比相同时,颗粒硬度随着模孔直径的增加而极显著提高(P<0.01)。各组颗粒耐久性指数(PDI)无显著差异(P>0.05),且都高于95%。2)模孔直径相同时,随着颗粒硬度的增加,肉鸡终末体重、平均日增重均逐渐降低,料重比逐渐升高。Ⅰ组的终末体重和平均日增重显著或极显著高于Ⅲ组(P<0.05或P<0.01),Ⅰ组料重比显著低于Ⅱ、Ⅲ组(P<0.05)。3)模孔长径比相同时,各组终末体重、平均日增重和平均日采食量均无显著差异(P>0.05);随着颗粒直径的增加料重比逐渐降低,且Ⅲ组料重比显著高于Ⅴ组(P<0.05)。综上所述,模孔长径比和直径的增大均会显著提高颗粒硬度。在一定范围内,提高颗粒硬度会使肉鸡终末体重和平均日增重降低,料重比升高,而增大颗粒直径则会使料重比降低。 展开更多
关键词 环模参数 肉鸡 颗粒饲料 加工质量 生长性能
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A Study on the Multi-Compartment Linear Circulation Pharmacokinetic Model for the Targeting Drug Delivery System
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作者 张志荣 永井恒司 《Journal of Chinese Pharmaceutical Sciences》 CAS 1996年第2期81-87,共7页
By analyzing the observed phenomena and the data collected in the study, a multi-compartment linear circulation model for targeting drug delivery system was developed and the function formulas of the drug concentratio... By analyzing the observed phenomena and the data collected in the study, a multi-compartment linear circulation model for targeting drug delivery system was developed and the function formulas of the drug concentration-time in blood and target organ by computing were figured out. The drug concentration-time curve for target organ can be plotted with reference to the data of drug concentration in blood according to the model. The pharmacokinetic parameters of the drug in target organ could also be obtained. The practicability of the model was further checked by the curves of drug concentration-time in blood and target organ(liver) of liver-targeting nanoparticles in animal tests. Based on the liver drug concentration-time curves calculated by the function formula of the drug in target organ, the pharmacokinetic behavior of the drug in target organ(liver) was analyzed by statistical moment, and its pharmacokinetic parameters in liver were obtained. It is suggested that the (relative targeting index( can be used for quantitative evaluation of the targeting drug delivery systems. 展开更多
关键词 Pharmacokinetic model for targeting drug delivery systems Multi-compartment linear circulation pharmacokinetic model Relative targeting index
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Ventilation control of tunnel drilling dust based on numerical simulation 被引量:10
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作者 JIANG Zhong-an WANG Ya-peng MEN Li-guo 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1342-1356,共15页
In order to control the dust pollution produced by air leg rock drill in the trolley area during the excavation of long-distance single ended tunnel,the full-scale physical model of working face was established by usi... In order to control the dust pollution produced by air leg rock drill in the trolley area during the excavation of long-distance single ended tunnel,the full-scale physical model of working face was established by using FLUENT software,and the numerical simulation analysis of tunnel drilling ventilation and dust removal parameters was carried out.The results show that it is difficult to control the dust pollution of the face by conventional ventilation,and the drilling dust is distributed in the range of 10 m from the face;after the introduction of the long pressure and short suction ventilation scheme,when the ratio of compressed air volume to exhaust air volume is 0.72,the height of the pressure fan is 2.5 m,the distance between the pressure fan and the palm face is 20 m,and the exhaust fan is 12 m away from the palm,the dust concentration control efficiency of the working face is increased by about 60%.Therefore,in the similar long-distance single head tunnel construction,it is appropriate to adopt the dust removal method of long-distance short suction and exhaust fan to ensure the working environment. 展开更多
关键词 dust pollution working environment numerical simulation ventilation parameters
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Nutrient-controlled growth of Skeletonema costatum : an applied model
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作者 孙科 丘仲锋 +1 位作者 何宜军 尹宝树 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期608-625,共18页
To model Skeletonema costatum blooms and their relationship with environmental parameters in situ, a S. costatum-specific zero-dimensional box model based on the mechanistic model Eco3M was established using physiolog... To model Skeletonema costatum blooms and their relationship with environmental parameters in situ, a S. costatum-specific zero-dimensional box model based on the mechanistic model Eco3M was established using physiological features. The parameters were calibrated using experimental counterparts, and simulations were compared with published laboratory findings. The resulting normalized objective function (NOF) values are less than 1.0 (and in most cases less than 0.58) and the values for the slope y (between 0.656 7-1.127 4) and R2 (between 0.806 8-0.971) are close to 1.0 for most of the sub-figures. This indicates good agreement between simulated and measured data and suggests that the model reproduces the general characteristics of S. costatum growth and use of nutrients under different N- or P-limiting conditions. The model is appropriate for further applications and can be used to test more scenarios using other nutrients. 展开更多
关键词 Skeletonema costatum red tide algal bloom MODELING GROWTH China Sea
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Modal Wave Number Spectrum for Mesoscale Eddies
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作者 KANG Ying, PENG LinhuiDepartment of Physics, Ocean University of China, Qingdao 266071, P.R.China 《Journal of Ocean University of Qingdao》 2003年第2期218-223,共6页
The variations of ocean environmental parameters invariably result in variations of local modal wave numbers of a sound pressure field. The asymptotic Hankel transform with a short sliding window is applied to the com... The variations of ocean environmental parameters invariably result in variations of local modal wave numbers of a sound pressure field. The asymptotic Hankel transform with a short sliding window is applied to the complex sound pressure field in the water containing a mesoscale eddy to examine the variation of local modal wave numbers in such a range-dependent environment. The numerical simulation results show that modal wave number spectra obtained by this method can reflect the location and strength of a mesoscale eddy, therefore it can be used to monitor the strength and spatial scale of ocean mesoscale eddies. 展开更多
关键词 nomal mode wave number spectrum mesoscale eddies
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Research on Wireless Sensor Networks in Agriculture
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作者 Jun Zhao 《International Journal of Technology Management》 2014年第6期12-14,共3页
This paper uses the hardware with ZigBee standard and communication protocol, it consists of wireless sensor network in the greenhouse that can timely sample temperature, humidity, collection of environmental paramete... This paper uses the hardware with ZigBee standard and communication protocol, it consists of wireless sensor network in the greenhouse that can timely sample temperature, humidity, collection of environmental parameters. At the same time, this design uses the GPRS module, the data will be collected through the Internet and send to the PC server, and can receive control instructions from the host computer, through the adjustment of agricultural facilities valve to reverse control environment parameters. 展开更多
关键词 Agriculture greenhouse wireless sensor network automatic control ZIGBEE
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IMPACTS OF CUMULUS PARAMETERIZATION AND RESOLUTION ON THE MJO SIMULATION
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作者 贾小龙 李崇银 凌健 《Journal of Tropical Meteorology》 SCIE 2009年第1期106-110,共5页
Madden-Julian Oscillations (MJO) in six integrations using an AGCM with different cumulus parameterization schemes and resolutions are examined to investigate their impacts on the MJO simulation. Results suggest that ... Madden-Julian Oscillations (MJO) in six integrations using an AGCM with different cumulus parameterization schemes and resolutions are examined to investigate their impacts on the MJO simulation. Results suggest that the MJO simulation can be affected by both resolution and cumulus parameterization, though the latter, which determines the fundamental ability of the AGCM in simulating the MJO and the characteristics of the simulated MJO, is more crucial than the former. Model resolution can substantially affect the simulated MJO in certain aspects. Increasing resolution cannot improve the simulated MJO substantially, but can significantly modulate the detailed character of the simulated MJO; meanwhile, the impacts of resolution are dependent on the cumulus parameterization, determining the basic features of the MJO. Changes in the resolution do not alter the nature of the simulated MJO but rather regulate the simulation itself, which is constrained by cumulus parameterization schemes. Therefore, the vertical resolution needs to be increased simultaneously. The vertical profile of diabatic heating may be a crucial factor that is responsible for these different modeling results. To a large extent, it is determined by the cumulus parameterization scheme used. 展开更多
关键词 climatology MJO simulation GCM cumulus parameterizations resolution
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Material Parameters of a Structural Steel with Plastic Strain Memory
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作者 Humayun KabirSheikh Muhammad Taein Yeo 《Journal of Mechanics Engineering and Automation》 2011年第1期10-17,共8页
The present work is concerned with the characterization of hardening parameters for an elasto-plastic continuum model, taking into account the memory effect of plastic strain amplitude, in order to predict the hystere... The present work is concerned with the characterization of hardening parameters for an elasto-plastic continuum model, taking into account the memory effect of plastic strain amplitude, in order to predict the hysteretic responses of a ferritic steel. This elasto-plastic three-dimensional model is based on the internal thermodynamic variables which composed of the nonlinear kinematic hardening and isotropic hardening with the plastic strain memorization. The emphasis is put on the determination of strain memory parameters along with other material parameters of the proposed model in order to better simulate the behavior of the material at different strain range. The material parameters are calibrated with the experimental stabilized loops of stress-strain curves available in the literature. The predicted stabilized loops from the simulation with the determined parameters show good agreement with the experimental results signifying the validity of the considered model. 展开更多
关键词 Elasto-plastic continuum model material parameters nonlinear hardening law plastic strain memory stabilized hysteresis loops.
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Macrokinetics of Ethylene Epoxidation over A-type Silver Catalyst
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作者 Liang Rujun Li Jianwei 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第3期44-52,共9页
By taking the surface chemical reactions as the rate-controlling step, a possible reaction mechanism for ethylene epoxidation to synthesize ethylene oxide over the A-type silver catalyst was developed, while it was as... By taking the surface chemical reactions as the rate-controlling step, a possible reaction mechanism for ethylene epoxidation to synthesize ethylene oxide over the A-type silver catalyst was developed, while it was assumed that the epoxidation reaction would take place between ethylene and the un-dissociated adsorbed oxygen O2 a on the solo active sites, while the deep oxidation would occur between ethylene and the dissociated adsorbed oxygen Oa on the adjacent multi-active sites. In order to describe the effect of 1,2-C2H4Cl2(EDC) inhibitor on the ethylene epoxidation process, the reversible reactions between EDC and vinyl chloride(VC) on the active sites of silver catalyst was introduced. According to the assumed mechanism, the hyperbolic macro-kinetic model of ethylene epoxidation over the A-type silver catalyst was established, and the macrokinetic experiments were carried out in an internal-recycle gradientless reactor operating at a pressure of 2.1 MPa and a temperature in the range of 217.8—249.0 ℃, with the gas composition(molar fraction) consisting of 15.82%—34.65% C2H4, 2.55%—7.80% O2, 0.88%—6.15% CO2, 0.15—2.61 μmol/mol of 1,2-C2H4Cl2 and 0.14—1.28 μmol/mol of C2H3 Cl. By means of the Simplex Optimal Method, the parameters of the macrokinetic models were estimated. Statistical test showed that the macrokinetic models developed for the A-type silver catalyst agree well with the experimental results. 展开更多
关键词 silver catalyst ethylene epoxidation reaction mechanism MACROKINETICS
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Stability analysis of combined project of fish, broiler and ducks: Dynamical system in imprecise environment 被引量:2
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作者 A. De K. Maity M. Maiti 《International Journal of Biomathematics》 2015年第5期263-294,共32页
In this paper, we consider three species harvesting model and develop a solution proce- dure which is able to calculate the equilibrium points of the model where some biological parameters of the model are interval nu... In this paper, we consider three species harvesting model and develop a solution proce- dure which is able to calculate the equilibrium points of the model where some biological parameters of the model are interval numbers. A parametric mathematical program is formulated to find the biological equilibrium of the model for different values of parame- ters. This interval-valued problem is converted into equivalent crisp model using interval operations. The main advantage of the proposed procedure is that we can present dif- ferent characteristics of the model in a single framework. Analytically, the existence of steady state and stabilities are looked into. Using mathematical software, the model is illustrated and the results are obtained and presented in tabular and graphical forms. 展开更多
关键词 Mathematical modeling three species harvesting interval biological para-meters stability.
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