针对钨离子交换工艺热力学参数缺乏的问题,测定了不同温度下氯型季铵树脂吸附钨酸根的平衡数据,由此计算出吸附过程的热力学参数.结果表明,吸附平衡数据符合Langmiur等温吸附方程;在求算Langmiur模型常数项时,非线性拟合方法对实验数据...针对钨离子交换工艺热力学参数缺乏的问题,测定了不同温度下氯型季铵树脂吸附钨酸根的平衡数据,由此计算出吸附过程的热力学参数.结果表明,吸附平衡数据符合Langmiur等温吸附方程;在求算Langmiur模型常数项时,非线性拟合方法对实验数据的拟合精度优于线性拟合的方法;氯型季铵树脂对钨酸根的吸附是吸热过程,ΔH为13.505 k J/mol,ΔS为0.098 k J/(mol·K),ΔG(298)为-15.833 k J/mol;并且,ΔG随着温度升高而变小,说明温度升高有利于获得更大的钨吸附容量,热力学分析与实验结果一致.展开更多
Visual-Inertial Odometry(VIO) fuses measurements from camera and Inertial Measurement Unit(IMU) to achieve accumulative performance that is better than using individual sensors.Hybrid VIO is an extended Kalman filter-...Visual-Inertial Odometry(VIO) fuses measurements from camera and Inertial Measurement Unit(IMU) to achieve accumulative performance that is better than using individual sensors.Hybrid VIO is an extended Kalman filter-based solution which augments features with long tracking length into the state vector of Multi-State Constraint Kalman Filter(MSCKF). In this paper, a novel hybrid VIO is proposed, which focuses on utilizing low-cost sensors while also considering both the computational efficiency and positioning precision. The proposed algorithm introduces several novel contributions. Firstly, by deducing an analytical error transition equation, onedimensional inverse depth parametrization is utilized to parametrize the augmented feature state.This modification is shown to significantly improve the computational efficiency and numerical robustness, as a result achieving higher precision. Secondly, for better handling of the static scene,a novel closed-form Zero velocity UPda Te(ZUPT) method is proposed. ZUPT is modeled as a measurement update for the filter rather than forbidding propagation roughly, which has the advantage of correcting the overall state through correlation in the filter covariance matrix. Furthermore, online spatial and temporal calibration is also incorporated. Experiments are conducted on both public dataset and real data. The results demonstrate the effectiveness of the proposed solution by showing that its performance is better than the baseline and the state-of-the-art algorithms in terms of both efficiency and precision. A related software is open-sourced to benefit the community.展开更多
文摘针对钨离子交换工艺热力学参数缺乏的问题,测定了不同温度下氯型季铵树脂吸附钨酸根的平衡数据,由此计算出吸附过程的热力学参数.结果表明,吸附平衡数据符合Langmiur等温吸附方程;在求算Langmiur模型常数项时,非线性拟合方法对实验数据的拟合精度优于线性拟合的方法;氯型季铵树脂对钨酸根的吸附是吸热过程,ΔH为13.505 k J/mol,ΔS为0.098 k J/(mol·K),ΔG(298)为-15.833 k J/mol;并且,ΔG随着温度升高而变小,说明温度升高有利于获得更大的钨吸附容量,热力学分析与实验结果一致.
基金supported by the National Key Research and Development Program of China(Nos.2016YFB0502004,2017YFC0821102)。
文摘Visual-Inertial Odometry(VIO) fuses measurements from camera and Inertial Measurement Unit(IMU) to achieve accumulative performance that is better than using individual sensors.Hybrid VIO is an extended Kalman filter-based solution which augments features with long tracking length into the state vector of Multi-State Constraint Kalman Filter(MSCKF). In this paper, a novel hybrid VIO is proposed, which focuses on utilizing low-cost sensors while also considering both the computational efficiency and positioning precision. The proposed algorithm introduces several novel contributions. Firstly, by deducing an analytical error transition equation, onedimensional inverse depth parametrization is utilized to parametrize the augmented feature state.This modification is shown to significantly improve the computational efficiency and numerical robustness, as a result achieving higher precision. Secondly, for better handling of the static scene,a novel closed-form Zero velocity UPda Te(ZUPT) method is proposed. ZUPT is modeled as a measurement update for the filter rather than forbidding propagation roughly, which has the advantage of correcting the overall state through correlation in the filter covariance matrix. Furthermore, online spatial and temporal calibration is also incorporated. Experiments are conducted on both public dataset and real data. The results demonstrate the effectiveness of the proposed solution by showing that its performance is better than the baseline and the state-of-the-art algorithms in terms of both efficiency and precision. A related software is open-sourced to benefit the community.
