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Reentry Attitude Tracking Control for Hypersonic Vehicle with Reaction Control Systems via Improved Model Predictive Control Approach 被引量:4
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作者 Kai Liu Zheng Hou +2 位作者 Zhiyong She Jian Guo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第1期131-148,共18页
This paper studies the reentry attitude tracking control problem for hypersonic vehicles(HSV)equipped with reaction control systems(RCS)and aerodynamic surfaces.The attitude dynamical model of the hypersonic vehicles ... This paper studies the reentry attitude tracking control problem for hypersonic vehicles(HSV)equipped with reaction control systems(RCS)and aerodynamic surfaces.The attitude dynamical model of the hypersonic vehicles is established,and the simplified longitudinal and lateral dynamic models are obtained,respectively.Then,the compound control allocation strategy is provided and the model predictive controller is designed for the pitch channel.Furthermore,considering the complicated jet interaction effect of HSV during RCS is working,an improved model predictive control approach is presented by introducing the online parameter estimation of the jet interaction coefficient for dealing with the uncertainty and disturbance.Moreover,considering the strong coupling effect between the yaw channel and roll channel,a coupled model predictive controller is designed by introducing the feedback of sideslip angle into the roll control channel to eliminate the coupling effect.Finally,the comparison simulations using the classical control method,MPC and IMPC approach are given to demonstrate the effectiveness and efficiency of the presented IMPC scheme. 展开更多
关键词 Hypersonic vehicle reentry attitude control mode predictive control jet interference factor reaction control systems
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Operational feasibility study of stagnation pressure reaction control for a mid-caliber non-spinning projectile
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作者 F.Bouquet 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期109-121,共13页
Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has develop... Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets. 展开更多
关键词 Supersonic projectile Feasibility study Ram air Stagnation pressure reaction control Simulation Attitude control
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Experimental studies of water hammer in propellant feed system of reaction control system 被引量:4
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作者 Avanish Kumar P.Satya Prasad M.Raghavendra Rao 《Propulsion and Power Research》 SCIE 2018年第1期52-59,共8页
Water hammer pressure transient produces large dynamic forces which can damage the pipes and other assemblies in the feed line of a reaction control system(RCS).It has led to the failure of pressure transducers monito... Water hammer pressure transient produces large dynamic forces which can damage the pipes and other assemblies in the feed line of a reaction control system(RCS).It has led to the failure of pressure transducers monitoring the manifold pressure in the feed line of RCS.Therefore,water hammer studies have been carried out to understand its effect in feed line.Feedline system has been simplified to develop a mathematical model and experiments have been carried out at extensive levels.The mathematical model was developed considering pipe of uniform c/s and moving liquid-gas interface.The experimental studies have been done using water as working medium instead of actual propellant.The studies showed that rate of pressurization have a very critical role on the water hammer amplitude.Sensitivity studies have been also carried out to study the effect of density,friction and initial liquid column length on water hammer amplitude. 展开更多
关键词 Water hammer reaction control system(RCS) Propellant feed system Experimental study TESTING
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Precisely Controlled Synthesis of Pt-Pd Octahedral Nanoframes as a Superior Catalyst towards Oxygen Reduction Reaction 被引量:2
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作者 叶春苗 黄宏文 曾杰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第5期581-587,I0002,共8页
Pt-based nanoframes represent a class of promising catalysts towards oxygen reduction reaction. Herein, we, for the first time, successfully prepared Pt-Pd octahedral nanoframes with ultrathin ridges less than 2 nm in... Pt-based nanoframes represent a class of promising catalysts towards oxygen reduction reaction. Herein, we, for the first time, successfully prepared Pt-Pd octahedral nanoframes with ultrathin ridges less than 2 nm in thickness. The Pt-Pd octahedral nanoframes were obtained through site-selected deposition of Pt atoms onto the edge sites of Pd octahedral seeds, followed by selective removal of the Pd octahedral cores via chemical etching. Due to that a combination of three-dimensional opens geometrical structure and Pt-skin surface compositional structure, the Pt-Pd octahedral nanoframes/C catalyst shows a mass activity of 1.15 A/mgPt towards oxygen reduction reaction, 5.8 times enhancement in mass activity relative to commercial Pt/C catalyst (0.20 A/mgPt). Moreover, even after 8000 cycles of accelerated durability test, the Pt-Pd octahedral nanoframes/C catalyst still exhibits a mass activity which is more than three times higher than that of pristine Pt/C catalyst. 展开更多
关键词 Pt-based nanoframes controlled synthesis Oxygen reduction reaction Mass activity
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Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst 被引量:5
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作者 Zhi Huan Weng Jin Yan Wang Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期936-938,共3页
A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the pr... A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the properties of reaction-controlled phasetransfer catalysis, and they had excellent catalytic ability to the oxidation of benzyl alcohol. No other by-products were detected by gas chromatography. Once the hydrogen peroxide was consumed completely, the catalyst precipitated from solvent, and the results of the catalyst recycle showed that the catalyst had high stability. 展开更多
关键词 HETEROPOLYTUNGSTATE reaction-controlled phase-transfer Benzyl alcohol BENZALDEHYDE Hydrogen peroxide
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A New Reaction-controlled Phase-transfer Catalyst System 被引量:1
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作者 MingQiangLI XiGaoJIAN GuiMeiWANG YanYU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第3期350-352,共3页
A new reaction-controlled phase-transfer catalyst system was designed and synthesized. In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxida... A new reaction-controlled phase-transfer catalyst system was designed and synthesized. In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxidant. The conversion of H2O2 was 100% and the yield of cyclohexene oxide was 87.1% based on cyclohexene. Infrared spectra showed that both fresh catalyst and the recovered catalyst do have completely same absorption peak, indicating the structure of catalyst is very stability and can be recycled. 展开更多
关键词 reaction-controlled phase-transfer catalyst CYCLOHEXENE epoxidation.
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KINETIC MODEL FOR DIFFUSION-CONTROLLED INTERMOLECULAR REACTION OF HOMOGENOUS POLYMER UNDER STEADY SHEAR 被引量:1
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作者 周持兴 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第2期135-138,共4页
The kinetic model for diffusion-controlled intermolecular reaction of homogenous polymer under steady shear was theoretically studied. The classic formalism and the concept of conformation ellipsoids were integrated t... The kinetic model for diffusion-controlled intermolecular reaction of homogenous polymer under steady shear was theoretically studied. The classic formalism and the concept of conformation ellipsoids were integrated to get a new equation, which directly correlates the rate constant with shear rate. It was found that the rate constant is not monotonic with shear rate. The scale of rate constant is N^-1.5 (N is the length of chains), which is in consistent with de Gennes's result. 展开更多
关键词 Kinetic model Diffusion-controlled reaction Flow field Intermolecular reaction
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Heteropolymolybdate as a New Reaction-controlled Phase-transfer Catalyst for Efficient Alcohol Oxidation with Hydrogen Peroxide
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作者 Zhi Huan WENG Jin Yan WANG Xi Gao JIAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期848-850,共3页
A new catalytic process for the synthesis of aldehyde from alcohol by oxidation with H202 with high selectivity, was studied. In this system, heteropolymolybdate [C7H7N(CH3)3]3 {PO4[MoO(O2)2]4} was utilized as the... A new catalytic process for the synthesis of aldehyde from alcohol by oxidation with H202 with high selectivity, was studied. In this system, heteropolymolybdate [C7H7N(CH3)3]3 {PO4[MoO(O2)2]4} was utilized as the reaction-controlled phase-transfer catalyst to catalyze oxidation of benzyl and aliphatic alcohols. The molar ratio of H2O2 and alcohol was 0.75, no other by-products were detected by gas chromatography, the results of oxidation reaction indicated that the catalyst has high activity and stability. 展开更多
关键词 Heteropolymolybdate reaction-controlled phase-transfer ALCOHOL oxidation.
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THE SOLID STATE CONTROLLED PHOTOCHEMICAL REACTION OF NITROBENZALDEHYDE WITH INDOLE
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作者 Ji Ben MENG Da Ming DU +2 位作者 Guo Xiang XIONG Wen Guang WANG Yong Mei WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第11期865-868,共4页
The solid state photochemical reaction of nitrobenzaldehyde with indole was investigated. Seven hey products were identified by IR, MS,^(1)H HMR and elemental analysis.
关键词 WANG THE SOLID STATE controlLED PHOTOCHEMICAL reaction OF NITROBENZALDEHYDE WITH INDOLE HIGH
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Reaction Torque Control of Redundant Free-floating Space Robot
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作者 Ming-He Jin Cheng Zhou +2 位作者 Ye-Chao Liu Zi-Qi Liu Hong Liu 《International Journal of Automation and computing》 EI CSCD 2017年第3期295-306,共12页
This paper presents the reaction torque based satellite base reactionless control or base disturbance minimization of a redundant free-floating space robot. This subject is of vital importance in the study of the free... This paper presents the reaction torque based satellite base reactionless control or base disturbance minimization of a redundant free-floating space robot. This subject is of vital importance in the study of the free-floating space robot because the base disturbance minimization will result in less energy consumption and prolonged control application. The analytical formulation of the reaction torque is derived in this article, and the reaction torque control can achieve reactionless control and satellite base disturbance minimization. Furthermore, we derive the reaction torque based control of the space robot for base disturbance minimization from both the non-strict task priority and strict task priority control strategy. The dynamics singularity in the proposed algorithm is avoided in this paper. Besides, a real time simulation system of the space robot under Linux/real time application interface(RTAI) is developed to verify and test the feasibility and reliability of the method. The experimental results demonstrate the feasibility of online reaction torque control of the redundant free-floating space robot. 展开更多
关键词 Redundant space robot reaction torque reactionless control base disturbance minimization Linux/real time application interface(RTAI)
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Balance recovery control for biped robot based on reaction null space method
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作者 Baoping WANG Renxi HU +1 位作者 Jinming ZHANG Chuangfeng HUAI 《控制理论与应用(英文版)》 EI 2009年第1期87-91,共5页
A biped walking robot should be able to keep balance even in the presence of disturbing forces. This paper presents a step strategy concept of biped walking robot that is stabilized by using reaction null space method... A biped walking robot should be able to keep balance even in the presence of disturbing forces. This paper presents a step strategy concept of biped walking robot that is stabilized by using reaction null space method. The called "step strategy" can be modeled by means of the reaction null space method that introduced earlier to tackle dynamic interaction problems of free-floating robots, or moving base robots in general. 6-DOF biped robot model simulations are used to confirm the validity. 展开更多
关键词 Biped robot Balance recovery control reaction null space Step strategy
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Mixed Reaction to Proposed Dual Standards for Birth Control
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《China Population Today》 2002年第Z1期19-20,共2页
关键词 Mixed reaction to Proposed Dual Standards for Birth control
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Boundary Control for a Class of Reaction-diffusion Systems
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作者 Yuan-Chao Si Cheng-Kang Xie Na Zhao 《International Journal of Automation and computing》 EI CSCD 2018年第1期94-102,共9页
Boundary control for a class of partial integro-differential systems with space and time dependent coefficients is consid- ered. A control law is derived via the partial differential equation (PDE) backstepping. The... Boundary control for a class of partial integro-differential systems with space and time dependent coefficients is consid- ered. A control law is derived via the partial differential equation (PDE) backstepping. The existence of kernel equations is proved. Exponential stability of the closed-loop system is achieved. Simulation results are presented through figures. 展开更多
关键词 STABILITY reaction-diffusion system boundary control BACKSTEPPING partial differential equation.
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Analysis of reaction torque-based control of a redundant free-floating space robot 被引量:5
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作者 Minghe JIN Cheng ZHOU +1 位作者 Yechao LIU Hong LIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第5期1765-1776,共12页
Owing to the dynamics coupling between a free-floating base and a manipulator, the non-stationary base of a space robot will face the issue of base disturbance due to a manipulator's motion. The reaction torque acted... Owing to the dynamics coupling between a free-floating base and a manipulator, the non-stationary base of a space robot will face the issue of base disturbance due to a manipulator's motion. The reaction torque acted on the satellite base's centroid is an important index to measure the satellite base's disturbance. In this paper, a comprehensive analysis of the reaction torque is made, and a novel way to derive the analytical form of the reaction torque is proposed. In addition,the reaction torque null-space is derived, in which the manipulator's joint motion is dynamically decoupled from the motion of the satellite base, and its novel expression demonstrates the equivalence between the reaction torque null-space and the reaction null-space. Furthermore, the reaction torque acted as an optimization index can be utilized to achieve satellite base disturbance minimization in the generalized Jacobian-based end-effector Cartesian path tracking task. Besides, supposing that the redundant degrees of freedom are abundant to achieve reaction torque-based active control, the reaction torque can be used to realize satellite base attitude control, that is, base attitude adjustment or maintenance. Moreover, because reaction torque-based control is a second-order control scheme, joint torque minimization can be regarded as the optimization task in reaction torque-based active or in-active control. A real-time simulation system of a 7-DOF space robot under Linux/RTAI is developed to verify and test the feasibility and reliability of the proposed ideas. Our extensive empirical results demonstrate that the corresponding analysis about the reaction torque is correct and the proposed methods are feasible. 展开更多
关键词 Attitude control Base disturbance Dynamics modeling reaction torque Real time simulator Space robot
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Implementation of Process Reaction Curve for Tuning of Temperature Control Parameters in a 10 L Stirred Tank Heater
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作者 Yulius Deddy Hermawan 《材料科学与工程(中英文A版)》 2011年第4X期572-577,共6页
关键词 电加热器 温度上升 反应曲线 调整参数 控制参数 搅拌槽 积分时间常数 PID控制
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基于无磷、无糖还原剂与接枝聚合法制备ABS控制方式研究
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作者 姜山 钟原 +5 位作者 李国锋 刘姜 张辉 张馨元 陆书来 叶海木 《合成树脂及塑料》 北大核心 2026年第1期17-23,共7页
采用无磷、无糖还原剂及接枝聚合法制备了丙烯腈-丁二烯-苯乙烯三元共聚物(ABS),考察了还原剂加入方式对聚合反应速率和接枝过程的影响。结果表明:无磷、无糖还原剂的加入方式对聚合反应速率和接枝过程都有较大影响;采用批次/连续滴加方... 采用无磷、无糖还原剂及接枝聚合法制备了丙烯腈-丁二烯-苯乙烯三元共聚物(ABS),考察了还原剂加入方式对聚合反应速率和接枝过程的影响。结果表明:无磷、无糖还原剂的加入方式对聚合反应速率和接枝过程都有较大影响;采用批次/连续滴加方式,能够实现对引发剂分解产生自由基速率的精准调控,改善了接枝效果,提升了粉料的增韧效率。其中,增量反应开始时,先加入90.000 g还原剂,剩余150.000 g随单体连续滴加,获得的粉料接枝率最高,达到45.66%±0.20%,所制ABS力学性能最好。 展开更多
关键词 丙烯腈-丁二烯-苯乙烯三元共聚物 接枝聚合 氧化还原引发剂 无磷 无糖 反应控制方式
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Fault-tolerant control with mixed aerodynamic surfaces and RCS jets for hypersonic reentry vehicles 被引量:5
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作者 He Jingjing Qi Ruiyun +1 位作者 Jiang Bin Zhai Rongyu 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第2期780-795,共16页
This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems(RCS) under external disturbances and subject to actuator faults.Aerodynamic ... This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems(RCS) under external disturbances and subject to actuator faults.Aerodynamic surfaces are treated as the primary actuator in normal situations,and they are driven by a continuous quadratic programming(QP) allocator to generate torque commanded by a nonlinear adaptive feedback control law.When aerodynamic surfaces encounter faults,they may not be able to provide sufficient torque as commanded,and RCS jets are activated to augment the aerodynamic surfaces to compensate for insufficient torque.Partial loss of effectiveness and stuck faults are considered in this paper,and observers are designed to detect and identify the faults.Based on the fault identification results,an RCS control allocator using integer linear programming(ILP) techniques is designed to determine the optimal combination of activated RCS jets.By treating the RCS control allocator as a quantization element,closed-loop stability with both continuous and quantized inputs is analyzed.Simulation results verify the effectiveness of the proposed method. 展开更多
关键词 control allocation Fault-tolerant control Hypersonic vehicles Quantized control reaction control system(RCS)
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Active disturbance rejected predictive functional control for space vehicles with RCS 被引量:3
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作者 TIAN Jiayi ZHANG Shifeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期1022-1035,共14页
Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitab... Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise. 展开更多
关键词 reaction control system(RCS) predictive functional control(PFC) generalized extended state observer(GESO) pulse width pulse frequency(PWPF) multiple-input multiple-output(MIMO)
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基于项目式学习的高三化学综合复习教学——蓝晒
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作者 杨发丽 于守丽 +2 位作者 郭玉林 李伏刚 陈瑞雪 《化学教育(中英文)》 北大核心 2026年第1期67-74,共8页
基于“素养为本”的教学理念,为提升学生在复杂情境中的实际问题解决能力,开发了融合化学原理与艺术创作的蓝晒工艺微项目。通过系统化的实验探究活动,引导学生运用学科知识分析实验现象、调控化学反应,实现理论与实践的结合,有效促进... 基于“素养为本”的教学理念,为提升学生在复杂情境中的实际问题解决能力,开发了融合化学原理与艺术创作的蓝晒工艺微项目。通过系统化的实验探究活动,引导学生运用学科知识分析实验现象、调控化学反应,实现理论与实践的结合,有效促进了学生高阶思维的发展。实践表明,该教学模式不仅增强了复习教学的实效性,更培养了学生的跨学科应用能力和创新意识,为项目式教学理念下的学科融合教学提供了可推广的实践案例。 展开更多
关键词 项目式学习 蓝晒 化学反应调控 物质转化
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泰和乌鸡的特异性PCR鉴定
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作者 许源升 张恬 +4 位作者 刘天睿 赵玉洋 蒋超 李慧 袁媛 《中国现代中药》 2026年第2期222-229,共8页
目的:建立泰和乌鸡的特异性聚合酶链式反应(PCR)鉴定方法,解决泰和乌鸡与其他乌鸡品种的混淆使用问题,完善乌鸡药材优质基原品种泰和乌鸡的药用质量控制体系。方法:收集泰和乌鸡与其他品种乌鸡、非乌鸡样品,采用泰和乌鸡特异性鉴别引物... 目的:建立泰和乌鸡的特异性聚合酶链式反应(PCR)鉴定方法,解决泰和乌鸡与其他乌鸡品种的混淆使用问题,完善乌鸡药材优质基原品种泰和乌鸡的药用质量控制体系。方法:收集泰和乌鸡与其他品种乌鸡、非乌鸡样品,采用泰和乌鸡特异性鉴别引物,建立特异性PCR鉴定方法并优化影响PCR反应的条件。结果:特异性PCR鉴定方法退火温度为62℃,循环24次,DNA模板用量约100 ng。经PCR及凝胶电泳后,可在泰和乌鸡样品DNA扩增产物约410 bp处观察到单一明亮的特异性鉴别条带,其他品种无该条带。结论:建立的特异性PCR鉴定方法可准确对泰和乌鸡进行鉴别,为其药用质量控制与标准研究提供了参考。 展开更多
关键词 乌鸡 泰和乌鸡 道地基原 特异性聚合酶链式反应 质量控制
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