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Table of Content

    28 February 2020, Volume 48 Issue 1
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    Effect of Chemical-Related Acid Leaching on Characteristics of Typical High Sulfur Coal
    HUANG Fang, CHEN Ying, XIN Shanzhi, MI Tie
    2020, 48(1):  5-15.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.001
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    This study mainly investigated the effect of the common acid leaching process on coal （Tongchuan high sulfur coal） characteristics. Several acid solutions were used in chemical leaching process. Organic and inorganic characteristics, thermochemical and kinetic analysis were carried out in the research. It was found that nitric acid easilyreacted with coal organic macromolecules and decomposed them into smaller molecules. The GC-MS analysis also showed that the nitric acid fractured instable coal macromolecular structure more easily compared to other acids. Nitric acid could react with sulfur and iron containing material to form acid soluble substances. Most acid solutions could significantly reduce the content of sodium, calcium and magnesium. However, hydrofluoric acid could effectively reduce silicon, aluminum and potassium. Hydrofluoric acid leaching process caused the activation energy of coal becoming higher than raw coal. While nitric acid, nitric acid and hydrochloric acid mixed leaching process caused coal sample reaction activation energy decreasing obviously；these suggested that the two coal samples after acid leaching are more likely to pyrolyze and combust.
    Study on Cu-Mn-Ce Ternary Catalysts Prepared by Co-Precipitation Method and Their Performance for Catalytic Oxidation of Toluene
    HU Minghua，SHI Ling，DING Ying，YUE Lin
    2020, 48(1):  16-22.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.002
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    Copper-manganese-cerium ternary compound catalysts with different Cu/Mn/Ce molar ratio were prepared by co-precipitation method. Their performances for catalytic oxidation of toluene were evaluated and they were characterized by XRF，BET，XRD，H2-TPR. The catalysts were prepared by replacing cerium with manganese while the molar ratio of Cu to （Mn and Ce） was constant， and the relationships of physicochemical property and oxidation behaviors of toluene were systematically investigated. The results showed that manganese and copper formed new catalytic centers，they were highly dispersed by CeO2，so the oxygen mobility of catalyst increased，and the catalytic activity was improved. As a result，the performance of synthesized catalyst with Cu/Mn/Ce molar ratio 1∶1∶3 for toluene oxidation was the best，and its T90 was 193 ℃.
    Application and Prospect of Wet Fume Gas Desulforization by Microbes
    LIU Xiaoye，SHI Ling，YUE Lin，CHEN Chen，WU Jing，LIU Yin
    2020, 48(1):  23-28.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.003
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    The wet fume gas desulforization（WFGD）by using limestone-gypsum may cause environmental pollution like haze，the desulforization process needs to be improved immediately. The WFGD by microbes would be a potential development direction for its advantages of low energy cost，low investment cost and no secondary pollution. In this paper，the authors summarized the mechanism，the status of research and application on two types of WFGD by microbes oxidation and microbes reduction based on the variable valence state of sulfur，and analyzed the advantages and disadvantages of WFGD by microbes and by limestone-gypsum on technological conditions， desulfurization effect， energy consumption and so on. The WFGD by microbes of reduction-type will probably be the leading direction in the field of WFGD by microbes in the future.
    Study on Water Extraction Process and Physicochemical Properties of Flavonoids in Hawthorn
    GUO Yanhua，LI Jiao，HUANG Gang，WU Wangxi，BAI Jianxun，ZHANG Caihong，XIONG Jiayan
    2020, 48(1):  29-36.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.004
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    The process conditions of flavonoids extracted from hawthorn with water were discussed. The effects of extraction time，temperature，solid-liquid ratio and acidity on flavonoids extracted from hawthorn were investigated；the extracted flavonoids type was determined by chemical color reaction and UV spectroscopy；the physical and chemical properties were investigated. The results showed that the suitable process conditions of water extraction of hawthorn flavone were as follows：the extracting time of 2 h，the temperature of 50 ℃ ，the solid-liquid ratio of hawthorn with distilled water of 1∶30，the acidity of pH = 8，the yield of flavonoids was 4. 96% under these conditions. The types of flavonoids from hawthorn which determined by color reaction and UV spectrum were flavonols and simple flavonoids. Food additives and metal ions had certain influence on the flavonoids content and the antioxidant activity of flavonoids.
    Synthesis and Application of Neohesperidin Dihydrochalcone
    WANG Gang，CAI Cai，WANG Yazhen，WANG Hongbo，XIE Xinchun，WAN Weixiong，HUANG Dongyun，HU Siqian
    2020, 48(1):  37-44.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.005
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    Neohesperidin dihydrochalcone （NHDC） is a new type of sweetener with high sweetness and low calorie，its sweetness is about 1 500-1 800 times of sucrose. It has good shielding bitter effect and physiological activity. In this paper，the extraction and synthesis of NHDC precursors，the extraction and synthesis of hesperidin and naringin，the extraction and synthesis of neohesperidin and the synthesis of NHDC were mainly introduced. The detection technology of NHDC and its application in food industry， medicine and feed industry were also introduced.
    Analysis of Excessive Resting Heart Rate and Influencing Factors of Freshmen in a University from 2015 to 2017
    ZHANG Qiumei，XIANG Rong
    2020, 48(1):  45-50.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.006
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    Objective To understand the excessive resting heart rate （RHR） of college freshmen and related influencing factors， so as to provide scientific basis for primary prevention of cardiovascular diseases. Methods Based on the physical examination of 12 849 freshmen enrolled in Jianghan University from 2015 to 2017，the detection rate of excessive RHR and the factors affecting the excessive RHR were analyzed. Objective Results Excessive RHR detection rate of 12 849 freshmen was 2. 23%，2. 26% for male and 2. 30% for female （χ2 = 0. 025，P > 0. 05）；excessive RHR detection rates in 2015，2016 and 2017 were 1. 85%，2. 30% and 2. 73%，respectively，which showed an increasing trend year by year （χ2 = 7. 558，P < 0. 05）；The detection rates of excessive RHR of college freshmen in hypertension group，overweight and obesity group，urban group，late night，family history of cardiovascular disease group were higher than those of non-hypertension group，nonoverweight and non-obesity group，rural group，non-late night，non-family history of cardiovascular disease group（χ2 values were 122. 485，8. 566，11. 263，78. 498，91. 192，P < 0. 05）. The multiple stepwise regression analysis showed that hypertension，obesity，staying up late，lack of physical exercise，town and family history of cardiovascular disease were risk factors for the excessive RHR of college freshmen（P < 0. 05）. Conclusion The excessive RHR of freshman is related to many factors，the prevention and treatment of cardiovascular diseases should be started from the youth and a healthy lifestyle should be advocated.
    One Case of POEMS Syndrome and Literature Review
    LI Xiaoli，ZOU Liang
    2020, 48(1):  51-54.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.007
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    ObjectiveTo explore the clinical manifestations， diagnosis and treatment of POEMS syndrome. Methods The clinical manifestation，laboratory examination，diagnosis and treatment of patients with POEMS syndrome were reported and reviewed in literature. Results The patient had bilateral legs numbness， M protein， sclerosing bone disease，elevated serum VEGF，splenomegaly，multiple serous effusion，changes in sex hormones，skin pigmentation，and pale nails，which met the diagnostic criteria of POEMS syndrome. The patient achieved good results with the treatment regimen of bortezomib combined with dexamethasone. Conclusion The misdiagnosis rate and missed diagnosis rate of POEMS syndrome are high. There is no uniform treatment plan at present. Early diagnosis is important to improve the survival rate and quality of life of the patients.
    Estimation of Leaf Nitrogen Content of Wheat Based on UAV Image at Filling Stage
    WANG Mengxuan，SHA Zhengxia，YANG Baohua，GAO Yuan
    2020, 48(1):  55-64.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.008
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    Nitrogen content is one of the important nutritional indicators of wheat. The traditional method of monitoring nitrogen content of wheat leaves in different growth stages was complicated and destructive. Therefore， a method for rapid prediction of nitrogen content in wheat using remote sensing images of unmanned aerial vehicle （UAV） was proposed in this study. The UAV images acquired during the wheat filling period were used for splicing and fusion based on the improved weighted average algorithm，which could effectively eliminate splicing marks and differences. Thus，wheat features were effective extracted，including RGB features，HIS features and vegetation indices（VIs），which were used to construct support vector regression（SVR）model. The experimental results showed that the accuracy of the HIS-based+VIs combination model was the highest. The validation set coefficient （R2） was 0. 774 and the root mean square error（RMSE） was 0. 363 7. The results indicated that the monitoring method based on UAV for the nutrition of wheat during grain filling was feasible， which also provided technical support for the management of wheat field.
    Estimation of Chlorophyll Content in Soybean Leaves Based on RGB Model
    SONG Yifan，ZHANG Wu，YAO Yuqing，HONG Xun，ZHANG Manman，LIU Lianzhong
    2020, 48(1):  65-72.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.009
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    Taking the soybean leaves chlorophyll as the research object，the chlorophyll SPAD estimation model was constructed based on RGB color space. In this experiment，the prediction for chlorophyll content in soybean leaves was carried out. Firstly，the image of soybean leaves in the natural environment was collected，the image noise was removed by median filtering，and the leaves were segmented from the background based on the kmeans algorithm. Then，the red（R），green（G），and blue（ B）values were extracted from the leaf images，the color feature parameters were constructed by operation combination，the chlorophyll content estimation model based on the color characteristic parameters of soybean leaves was established，and the accuracy was evaluated and verified. Finally，four color characteristic parameters such as R/G/B，R/（R+G-B），B/（R+G-B）and G/（R+GB） were combined， and the regression analysis was carried out on these four color characteristic parameters and chlorophyll measured values. The verification results showed that the RGB color space had the highest combination accuracy，R2 was 0. 438，AARD was 9. 58%，and RMSE was 2. 862. The method can predict the chlorophyll content in soybean leaves quickly and non-destructively，and it provides a scientific basis for assessing the physiological state of soybean.
    Tea Garden Irrigation Remote Control System Based on STM32
    XU Weihao，ZHANG Wu，ZUO Guanpeng，ZHANG Chao，YAO Yuqing，FENG Jinlei，MIAO Benben
    2020, 48(1):  73-80.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.010
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    In order to realize the accurate detection of water needs information in process of tea tree growth and the automatic control of accurate irrigation of tea garden，a system with Cortex-M3 as the core was designed，and the data were stored with two methods of SD memory card and server. The automatic control system used GPRS for data transmission. The system could realize automatical monitoring and regulating for water demand of tea tree at different growth stages. The experimental results show that the system is reliable，simple to operate and has strong expansion ability；it has good market application prospects.
    Business Process Clustering Method Based on k-means and Elbow Method
    LONG Wenjia，ZHANG Xiaofeng，ZHANG Lian
    2020, 48(1):  81-90.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.011
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    Process mining is to extract structured process information from the actual business event log. Process mining technology is now widely used in the process discovery and assisted modeling of real business processes，and can help to improve existing business processes through differential analysis. This paper proposed a cluster-based process mining method. Firstly，it described the activity-based process pathway starting from the event log，then analyzed the pathway clustering of the active view awareness based on distance，and analyzed the characteristics of process through the clustering results. These can provide decision making for process change. This paper took the actual conference registration system as the experimental object，demonstrated the effectiveness of the proposed method，it provides support for decision making for process modification.
    No-Reference Image Quality Assessment Under Blocking Artifacts Based on Bidirectional Filtration
    MA Lu，YANG Wenfei
    2020, 48(1):  91-96.  doi:10.16389/j.cnki.cn42-1737/n.2020.01.012
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    To evaluate the image quality without reference under blocking effect，the author proposed a bidirectional filtration （BIF） method，which aims at providing a new idea for boundary selection，and resolved the image evaluation under blocking effect more effectively by distinguishing the true and false boundary of the image. The method filtered the image boundary layer by layer from two different fields to locate the true boundary effectively. Finally，the evaluation values were obtained through the evaluation model. Compared with SSIM model，the data obtained from the experimental results were improved to a certain extent. It is concluded that this method is more accurate in evaluating the no-reference image under blocking effect.