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Bio-machining technology is widely recognized as an environmentally friendly processing method for metals removal. In order to reveal the removal mechanism of ferroalloy corroded by Acidithiobacillus Ferrooxidans, ferroalloy workpieces were prepared by mixing 50% the powder of Fe with Co, Ni and Cu, and they were sintered with vacuum hot-pressing, A set of material removal experiments were carried out by shaking the ferroalloy with the bacterial strain culture solution of Fe3+level at 5.5 g/L, and the material removal amount, surface morphology and roughness, and electrochemical characteristics of ferroalloy workpieces were determinated. The results showed that the Fe-based alloys containing Co, Ni, Cu, and Sn can be bio-machined, and the surface roughness of the ferroalloys significantly increased after machining. The material removal amount (MRA) of 8 hours of bio-machining ranked in the order of Fe50Co (42.3) >Fe50Cu (36.4) > Fe50Ni (21.6)>Fe50Sn (14.3). The MRA of each ferroalloy increased with the processing time, and the results could be fitted in a power function with machining time. In conclusion, the activity of the metal, the passivation on the alloy surface and the accelerated corrosion of the inert metal on the active metal were the three most important factors affecting MRA of ferroalloys. The additional reaction between Fe and newly generated metal ions by Fe3+, as well as the uneven reaction layer of workpieces was involved in the process of bio-machining.

To effectively mitigate the spread of infections during public health crises, precise and timely distribution of medical supplies is crucial. This paper proposes the integration of the metro-based underground logistics system (M-ULS) into the delivery process to address the vehicle routing problem (VRP). Considering various factors related to the metro-based VRP in public health emergencies, we formulate a mixed-integer nonlinear function model that aims to minimize total delivery costs while maximizing the load factor of medical vans and the average demand index concerning demand urgency and satisfaction rate of medical centers. To achieve this, we develop an improved adaptive genetic algorithm (IAGA) that incorporates adaptive crossover, adaptive mutation, and an elitist strategy. A case study is conducted to verify and analyze the performance of the optimized model and solving algorithm. Extensive numerical experiments are carried out to assess the economical and efficient advantages of M-ULS and the computational efficiency and solution quality of IAGA. Sensitivity analysis is conducted to evaluate the impact of medical van capacity on the routes. Lastly, we consider inter-medical-center transfer (IMCT) to further enhance emergency health response.

The application of hydraulic oscillator can solve the problems of large friction and serious pressure support in the drilling process of extended reach well and long horizontal well, but the conventional hydraulic oscillator parameter setting is not reasonable, high pressure consumption, easy to make the ground machine pump overload operation and failure. Therefore, based on the LuGre dynamic friction model theory, a calculation model for the friction between drill string and rock wall under the condition of longitudinal oscillation is established, and the influence law of hydraulic oscillator oscillation parameters on drag reduction efficiency is studied. The results show that the change of oscillation intensity, oscillation frequency and oscillation amplitude can improve the drag reduction efficiency, and the increase trend of drag reduction efficiency is first increased and then decreased. The selection of each parameter has the optimal value. According to the analysis of orthogonal test results, it is found that the reduction degree of friction between drill string and borehole wall rock by each parameter is in the order of oscillation intensity, oscillation frequency and oscillation amplitude from the largest to the smallest.

To evaluate the effect of the traditional Chinese procedure abdominal Tuina (AT) on chronic fatigue syndrome (CFS).

The photoacoustic spectroscopy (PAS) technique has emerged as a valuable tool for the study of soil materials. The present work developed the experimental set-up for near infrared (800–2400 nm) photoacoustic spectroscopy (NIR-PAS), which consists of photoacoustic (PA) accessory, tungsten bromine lamp, monochromator, chopper and lock-in-amplifier, and this spectrometer was first applied to record the spectra of soils (n= 50) collected from the Loess Plateau of China; partial least-squares regression (PLSR) models and leave-one-out cross-validation were used to predict soil organic matter (SOM), clay, carbonate and available phosphorus content. The spectra varied among different soil samples; SOM played an important role in the spectral appearance, and the intensity and position of five typical absorption bands significantly shifted owing to the variances in the components and structure of SOM. The PLSR model demonstrated a good performance in the prediction of SOM with a root mean square error of 2.5 g kg−1and a ratio of standard deviation to prediction error of 2.3. This pilot study demonstrates that NIR-PAS exhibits typical infrared absorptions and may be suitable for analysing soil samples.

The photoacoustic spectroscopy (PAS) technique has emerged as a valuable tool for the study of soil materials. The present work developed the experimental set-up for near infrared (800–2400 nm) photoacoustic spectroscopy (NIR-PAS), which consists of photoacoustic (PA) accessory, tungsten bromine lamp, monochromator, chopper and lock-in-amplifier, and this spectrometer was first applied to record the spectra of soils (n = 50) collected from the Loess Plateau of China; partial least-squares regression (PLSR) models and leave-one-out cross-validation were used to predict soil organic matter (SOM), clay, carbonate and available phosphorus content. The spectra varied among different soil samples; SOM played an important role in the spectral appearance, and the intensity and position of five typical absorption bands significantly shifted owing to the variances in the components and structure of SOM. The PLSR model demonstrated a good performance in the prediction of SOM with a root mean square error of 2.5 g kg^−1 and a ratio of standard deviation to prediction error of 2.3. This pilot study demonstrates that NIR-PAS exhibits typical infrared absorptions and may be suitable for analysing soil samples.

The elastoplastic phenomenon of the structures will be advent under the action of the strong earthquakes, the presented research on the vibration control of the ones is chiefly concentrated on fuzzy and neuro-controller with the expense of bigger energy. In the paper, the 3-storey benchmark building is used as research object, the control strategy of vibration system with fractional-order is studied. The control method based on acceleration responses output is emphatically concerned as it is usually adopted in most actual application of active vibration control techniques. The concrete courses include the following three steps: the integer-order approximation of fraction-order, the transfer function reduction in frequency-domain which base on Pade approximation, the controller design and simulation. In the last, an example is used to show the feasibility of proposed method.