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| 1 | Yielding behavior of triplex medium Mn steel alternated with cooling strategies altering martensite/ferrite interfacial feature显示文摘In this paper, we report the influence of cooling processes on the yielding behavior of a medium Mn steel(MMS) with triplex microstructure, i.e. austenite(γ), ferrite(α) and as-quenched martensite(α’). After the intercritical annealing(IA) at both 725℃ and 750℃, the steel was subjected to the two cooling processes, i.e. air cooling(AC) and water quenching(WQ). It exhibits the discontinuous yielding after the AC following the IA at 750℃ while the continuous yielding after the WQ. Compared with WQ process,both the dilatometry and the microstructural examinations show that the AC process leads to lower Ms temperature, larger retained austenite(RA) fraction and less martensite, the latter is always companied with geometry necessary dislocations(GNDs) generated near the α/α’ interfaces. Considering the complexity of nanosized tri-phases in this steel, the presence of martensite with key features in the resultant specimens was systematically examined by atom probe tomography(APT) on the samples prepared by the specific target lift-out method. The APT results directly revealed the C/Mn co-segregation at the α’/αinterfaces in the AC samples but not in WQ samples. The numerical simulation results further suggest that the segregation of C and Mn at the α’/α interfaces may be due to different mechanisms. We conclude that the yielding of triplex MMS is determined by both the quantity of GNDs generated near theα/α’ interfaces, which increases with martensite fraction, and the extent of their immobilization resulting from the interfacial segregation of solute atoms when the presence of martensite is sufficient. WQ tends to suppress the discontinuous yielding of MMS since the rapid cooling may promote more martensite formed with the increasing quantity of GNDs and prevent the interfacial segregation of both C and Mn. | Bin Hu Xiao Shen Qinyi Guo Qinghua Wen Xin Tu Cancan Ding Fanglin Ding Wenwen Song Haiwen Luo | 2022 | Journal of Materials Science & Technology2022，，31： | 2 |
| 2 | Ten-year Etiologic Review of Chinese Children Hospitalized for Pediatric Cataracts显示文摘Purpose:Our aim was to obtain a better understanding of the etiologies and characteristics of pediatric cataracts treated at a single facility in China.Methods:.Medical records accrued over a 10-year period(from August, 2003 to July, 2013) at Shengjing Hospital of China Medical University were reviewed retrospectively,ide ntifying all patients treated for various subtypes of pediatric cataract..A database with 367 subjects under 14 years of age(598, including second-round surgeries) was generated.Results:.Of this cohort(n =367; males: 232, 63.2%; females: 135, 36.8%), 200 patients(54.5%) had bilateral cataracts,and 258(70.3%) were under 3 years of age. In all age groups and in all subtypes of pediatric cataract,.males were most commonly affected..Congenital cataract was the most prevalent subtype, accounting for 296 patients(80.7%). Most congenital cataracts were associated with other ocular or systemic abnormalities;.and in 48 patients(16.22%),.they were hereditary..Traumatic cataract was the most common subtype(85.92%) of acquired cataract. The few instances of cataracts due to steroids(n=3) or to metabolic disorders(n=2) occurred in males and involved both eyes.Conclusion: The majority of pediatric cataracts in this patient population were congenital in nature. A significant lag in ophthalmologic evaluation of Chinese infants was evident and should be addressed by educating both children and parents on risk factors for cataract development. Regular assessments are especially important in children subjected to long-term systemic steroid treatments. | Zixun Song Daixin Zhao Cancan Lv Wei Pu Wei Xiao | 2014 | Eye Science2014，29，3： | 1 |
| 3 | Discharge rate consistency of each channel for UAV-based pneumatic granular fertilizer spreader显示文摘Unmanned aerial vehicles(UAVs)are widely being used to spread granular fertilizer in China.Granular fertilizer spreaders equipped with UAVs are mainly centrifugal disc-type and pneumatic.The multichannel pneumatic granular fertilizer spreaders(MPGFSs)have a banded fertilizer deposition distribution pattern,which are more suitable for variable rate fertilization with high precision requirement than the circular deposition distribution pattern of disc-type granular fertilizer spreaders(DGFSs).However,the existing MPGFS has the disadvantage of inconsistent discharge rate of each channel,which affects the uniformity of fertilization.In order to explore the causes of inconsistent discharge rate of each channel,the discrete element method(DEM)and bench test were performed to analysis the discharge process of the fluted roller fertilizing apparatus and distribution of fertilizer in axial direction of fluted roller.The computational fluid dynamics(CFD)was used to simulate the airflow field of pneumatic system to analyze the influence of airflow on the movement of fertilizer particles.The simulation results of the discharge process of the fluted roller fertilizing apparatus showed that the filling velocity at the axial ends of the fluted roller fertilizing apparatus was lower than that of the middle.The reason was that the filling capacity was weak near the wall.The simulated results of the airflow field without partitions showed that the airflow provided by the axial flow fan was rotational,and this caused the particles to move irregularly in the throat,resulting in inconsistency discharge rate of each channel.Based on the analysis of reasons of inconsistent discharge rate of each channel,a MPGFS with partitions in the throat was developed.The discharge rate bench tests were carried out to optimize the partition spacing parameters,and fertilization test was performed to test the performance of the improved MPGFS.The discharge rate test results showed better consistency with partition.The coefficient of variation(CV)of the discharge rate of each channel was 20.16%without the partition and 7.70%with the optimal partition.The fertilizer spreading uniformity bench test results shown that the CV of spreading uniformity of MPGFS without partitions was 15.32%,and that MPGFS with partitions was 8.69%.The partitions design was beneficial to improve the consistency of each channel discharge rate and the uniformity of fertilization.The finding can provide a strong reference to design the MPGFS. | Xunwei Wang Rui Jiang Zhiyan Zhou Cancan Song Xiwen Luo Ruifeng Bao Zichen Lyu Junhao Huang Jianqin Lin | 2023 | International Journal of Agricultural and Biological Engineering2023，16，4： | 1 |
| 4 | Characterization and Comparison of Cellulose Extraction from Ginger Stalk by Two Different Chemical Treatments显示文摘Agricultural residues are important renewable biomass resources that have not received much research attention. Ginger stalk is a major agricultural waste in China.The extraction of cellulose from ginger stalk would convert this waste into a high value-added product and, simultaneously, contribute to environmental protection. This research studied the characteristics of cellulose extracted from ginger stalk by two different treatments:(i) potassium hydroxide(KOH) treatment and(ii) nitric acid-ethanol(NAE) treatment. The optimal condition for the KOH treatment was obtained, it was at 1∶30 solidto-liquid ratio(SLR) for 5 h extraction time with 14 wt% KOH. The optimal condition for the NAE treatment was as follows: 1∶40 SLR, 4 h extraction time, and a reaction temperature of 90℃. However, the cellulose obtained by NAE treatment was severely degraded than that by KOH treatment. The Fourier-transform infrared(FT-IR) spectroscopy analyses revealed that both treatments successfully dissolved the lignin and hemicellulose. Two treatments showed a higher cellulose yield, and the extracted cellulose had more crystal structure. | CanCan Zhou XiaoMing Song Shuai Wang FuShan Chen | 2017 | Paper And Biomaterials2017，2，2： | 1 |
| 5 | Spatio-temporal differentiation of spring phenology in China driven by temperatures and photoperiod from 1979 to 2018显示文摘Large amounts of data accumulated in ecology and related environmental sciences arouses urgent need to explore useful patterns and information in it.Here we propose coclustering-based methods and a temperatures-photoperiod driven phenological model to explore spatio-temporal differentiation in long-term spring phenology in China.First,we created the first bloom date(FBD)dataset in China from 1979 to 2018 using the extended spring indices and China Meteorological Forcing Dataset.Then we analyzed the dataset using Bregman block average co-clustering algorithm with I-divergence(BBAC_I)and kmeans algorithm.Such analysis delineated the spatially-continuous phenoregions in China for the first time.Results showed three spatial patterns of FBD in China and their temporal dynamics for 40 years(1979–2018).More specifically,overall late spring onsets occur in 1979–1996,in which areas located in Jiangxi,northern Xinjiang and middle Inner Mongolia experienced constant changing spring onsets.Overall increasingly earlier spring onsets occur in 1997–2012,in which areas located in Fujian,Hunan and eastern Heilongjiang experienced the most variable spring onsets.Stable early spring onsets over China occur after 2012.Results also showed 15 temporal patterns of spring phenology over the study period and their spatial delineation in China.More specifically,most areas in China have the same FBD category for 40 years while northern Guizhou,Hunan and southern Hubei have the same category in 1979–1997 and then fluctuate between different categories.Finally,our results have certain directive significance on the design of existing observational sites in Chinese Phenological Network. | Xiaojing WU Changxiu CHENG Cancan QIAO Changqing SONG | 2020 | Science China Earth Sciences2020，63，10： | 1 |
| 6 | Laser tracking leader-follower automatic cooperative navigation system for UAVs显示文摘Currently,small payload and short endurance are the main problems of a single UAV in agricultural applications,especially in large-scale farmland.It is one of the important methods to solve the above problems of UAVs by improving operation efficiency through multi-UAV cooperative navigation.This study proposed a laser tracking leader-follower automatic cooperative navigation system for multi-UAVs.The leader in the cluster fires a laser beam to irradiate the follower,and the follower performs a visual tracking flight according to the light spot at the relative position of the laser tracking device.Based on the existing kernel correlation filter(KCF)tracking algorithm,an improved KCF real-time spot tracking method was proposed.Compared with the traditional KCF tracking algorithm,the recognition and tracking rate of the optimized algorithm was increased from 70%to 95%in indoor environment,and was increased from 20%to 90%in outdoor environment.The navigation control method was studied from two aspects:the distance coordinate transformation model based on micro-gyroscope and navigation control strategy.The error of spot position was reduced from the maximum(3.12,−3.66)cm to(0.14,0.12)cm by correcting the deviation distance of the spot at different angles through a coordinate correction algorithm.An image coordinate conversion model was established for a complementary metal-oxide-semiconductor(CMOS)camera and laser receiving device at different mounting distances.The laser receiving device was divided into four regions,S0-S3,and the speed of the four regions is calculated using an uncontrollable discrete Kalman filter.The outdoor flight experiments of two UAVs were carried out outdoors using this system.The experiment results show that the average flight error of the two UAVs on the X-axis is 5.2 cm,and the coefficient of variation is 0.0181.The average flight error on the Z-axis is 7.3 cm,and the coefficient of variation is 0.0414.This study demonstrated the possibility and adaptability of the developed system to achieve multi-UAVs cooperative navigation. | Rui Ming Zhiyan Zhou Zichen Lyu Xiwen Luo Le Zi Cancan Song Yu Zang Wei Liu Rui Jiang | 2022 | International Journal of Agricultural and Biological Engineering2022，15，2： | 0 |
| 7 | Fish as a source of acoustic signal measurement in an aquaculture tank:Acoustic sensor based time frequency analysis显示文摘Acoustic signals travels rapidly in water without attenuating fish telemetry.The digital sonar and passive acoustic has been used for fish monitoring and fish feeding.However,it is an urgent need to introduce new techniques in order to monitor the growth rate of fish during harvesting and without causing adverse effects to the harvested fish.Therefore,a novel technique was introduced to probe the acoustic signal frequency ratio in absence and presence of the fish in tanks,which basically uses an acoustic sensor(hydrophone),acoustic signal processing system(scope meter),and a signal monitoring system(fluke view).Acoustic signals were selected from 48-52 Hz frequency,measure of dispersion of frequency signal represented as a function of time via Xlstat software.Measure of dispersion displayed a significant effect of acoustic signal in the presence and absence of the fish in tanks.These optimised protocols of this study will help to control and prevent excessive wastage of feed and enhance proper utilization of feed that chiefly enhance fish growth in aquaculture. | Shahbaz Gul Hassan Shakeel Ahmad Shafqat Iqbal Ehsan Elahi Murtaza Hasan Daoliang Li Zhiyan Zhou Adnan Abbas Cancan Song | 2019 | International Journal of Agricultural and Biological Engineering2019，12，3： | 0 |
| 8 | Test and evaluation method for endurance performance of electric multi-rotors spraying drones显示文摘The endurance performance(EP)of electric multi-rotors spraying drones(EMSDs)is a key technical indicator that ensures the completion of tasks and improves their usefulness.To improve the EP of current EMSD,a test system was designed to determine the EP based on the EMSD test platform,and the performance evaluation method was studied.Firstly,a test model was established to determine the equivalent energy dissipation using the performance-testing platform of the EMSD.Secondly,a multisensory test system was constructed.An attitude sensor,high-power DC power supply,infrared thermal imager,and serial port server were selected.The mounting fixture was designed to meet the universal mounting requirements of drone.In addition,the software LabVIEW was employed to program the code for the controller and the host computer,where functions such as data collection,data processing,communication,and graphical user interface(GUI),were performed reliably in real time.Thirdly,the test method was explored by considering factors such as the power consumption,thermal efficiency ratio,and unit load power consumption rate.In particular,a comprehensive index method and expert consultation weight method were used to evaluate the EP of the EMSD with multiple indexes.Finally,a systematic real-machine test was carried out on the three types of drones that are currently widely used in the market.The results verified the effectiveness and feasibility of the proposed method,which was employed to test and evaluate the EP based on the EMSD performance testing platform.At the same time,it can provide a reference for the development of the EMSD. | Rui Ming Zhiyan Zhou Xiwen Luo Yubin Lan Xingang He Cancan Song Rui Jiang Luhong Tian Shahbaz Gul Hassan | 2019 | International Journal of Agricultural and Biological Engineering2019，12，2： | 0 |
| 9 | Design and test of centrifugal disc type sowing device for unmanned helicopter显示文摘In China,it is difficult for manned aircraft to sow seeds in small and scattered plots,especially in areas including hills,swamps,telegraph poles,windbreaks,and residential areas;in such terrain,the sowing machinery cannot function properly.However,unmanned helicopters(UHs)are flexible enough to control and adapt to the complex environments that are not easily accessible by terrain sowing machinery and large agricultural aircraft,which have been widely used in agriculture.In this study,a centrifugal disc-type sowing device for an unmanned helicopter(CDTSDUH)was designed.The factors influencing the seed velocity when the seeds move away from the disc were explored by analyzing the forces of the seed acting on the sowing disc and the wind field of the UHs.The influential factors include the distance from the falling mouth to the center of the disc,the offset angle of the falling mouth,and the rotation speed of the disc.An orthogonal test was designed with the sowing width and the curvature of the sowing area as the indexes.The test results showed that the three factors mentioned above had a greater impact on the sowing width than the curvature of the seeding area.Moreover,the superior parameters of the disc were determined.It was also suggested that the above factor levels had little effect on the offset width of sowing.The results of the test conducted for studying the sowing uniformity of the CDTSDUH indicated that the maximum and minimum difference values among the number of particles of the sampling points in the forward direction was 11 and 8,and the coefficient of variation of the number of particles in each row was more than 20%,indicating less uniformity was achieved when sowing in the lateral(perpendicular to the forward direction)direction,as compared to that in the forward direction.This study determined the ideal values for the radius of particles position,the offsetting angle,and the disc speed of the sowing machinery designed.Furthermore,considering that there are so many factors that influence the manner in which a UH functions,more analysis results and test data of influencing factors need to be acquired by experiments.The uniformity of sowing needs to be further improved.The results provided some theoretical and experimental references for the technology research on the centrifugal disc-type sowing device for UHs. | Cancan Song Zhiyan Zhou Xiwen Luo Yubin Lan Xingang He Rui Ming Keliang Li Shahbaz Gul Hassan | 2018 | International Journal of Agricultural and Biological Engineering2018，11，2： | 0 |
| 10 | Optimization of aviation adjuvants based on wettability analysis for insecticide application on maize using UAV显示文摘Adjuvants can increase the control efficacy of diseases and insect pests by changing the physico-chemical properties of pesticides.Most of the aviation spray adjuvants are versions of ground adjuvants.Maize insecticide sprays with unmanned aerial vehicles(UAV),have problems such as relatively low droplet deposition rate and poor wettability.Hence,wettability research and optimization tests for aviation spray adjuvants are needed.The present study screened 12 spray adjuvants using physico-chemical property experiments.The adjuvants were applied to improve the droplet deposition and control efficacy in maize borers controlling by UAV.The selected spray adjuvants were Po2(a hyperbranched polymer adjuvant)and VO3(a vegetable oil adjuvant).Results showed that,(1)When Po2 was added in water-dispersible granules(WGs)at volume rate of 12 L/hm2,the dynamic surface tension(DST)of WGs was decreased by 37.41%,and the maize leaves were covered by droplets 100%,the droplet deposition was increased by 104%and maize borer control was increased by 46%;(2)VO3 decreased the surface tension of ultra-low-volume(ULV)formulation by 12.02%and the maize leaves were covered by droplets 100%.The effect of VO3 on improving the droplet deposition and control efficacy at 12 L/hm2 with ULV was not significant.Thus,the addition of aviation spray adjuvant to improve the wettability of WGs significantly improved the droplet deposition and control efficacy but it had no significant effect on the ULV formulation. | Yu Zang Zhiyan Zhou Ying Zang Xiwen Luo Juan Liao Rui Ming Cancan Song Le Zi Rui Jiang Hanxiang Xiao | 2021 | International Journal of Agricultural and Biological Engineering2021，14，5： | 0 |
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