Table of Content

25 September 2022, Volume 42 Issue 5

Previous Issue    Next Issue

Existence and uniqueness of solutions for a class of dynamic Melan equations

TANG Mengying, ZHANG Jian, WANG Yongda

2022, 42(5):  449-453.  DOI: 10.3969/j.issn.1000-1565.2022.05.001

Asbtract ( 447 )   PDF (327KB) ( 446 )  

References | Related Articles | Metrics

To solve a dynamic Melan equation, which is viewed as a beam model for dynamic suspension bridges, Galerkin’s method and the contraction mapping principle are applied to the nonlinear non-local Melan equation. The existence and uniqueness results are obtained.

A numerical method and its fast implementation for multi-term fractional nonlinear wave equations

SHAO Linxin, SHEN Zhuoyang, MA Geqinzhou, MIN Jie, HUANG Jianfei

2022, 42(5):  454-462.  DOI: 10.3969/j.issn.1000-1565.2022.05.002

Asbtract ( 322 )   PDF (490KB) ( 382 )  

References | Related Articles | Metrics

A linearized numerical method for multi-term time fractional nonlinear wave equations with a spatial fourth-order derivative is derived. To avoid solving the nonlinear system of equations, a linearized technique is applied to discretize the nonlinear term. Then, the convergence of this presented method is rigorously proved with the first-order accuracy in time and the fourth-order accuracy in space. It is worth mentioning that the presented method can handle the initial singularity, and can be fast calculated by the sum-of-exponentials technique. Finally, numerical experiments are given to verify the effectiveness of this method and the correctness of the theoretical results.

Effect of the elememtal ratio of Cd to Se on the luminescent properties of CdSe quantum dots

DING Yanan, ZHENG Yibo, LAI Weidong, LI Shuguang, WEI Zhiren, LI Zhiqiang, WANG Chunsheng

2022, 42(5):  463-467.  DOI: 10.3969/j.issn.1000-1565.2022.05.003

Asbtract ( 378 )   PDF (827KB) ( 379 )  

References | Related Articles | Metrics

Cadmium selenide(CdSe)quantum dots have the advantages of high fluorescence quantum yield, good stability and easy spectrum adjustment. They have broad application prospects in the fields of light-emitting diodes, solar cells and fluorescent labeling etc. It is of great significance to study the effects of different process conditions on their properties. Using mercaptopropionic acid(3-MPA)as coating agent, a series of CdSe quantum dots have been prepared by aqueous reflux reaction at 100 ℃ for 120 min. The changes of morphology, band gap and optical properties of the samples with different elemental ratio of Cd to Se are discussed. The size of CdSe quantum dots is about 2.19 nm to 2.57 nm. The strongest excitation peak locates at 431 nm, the emission peak is at 561 nm, and the absorption spectrum blueshifts from 460 nm to 450 nm, indicating that the elemental ratio of Cd to Se has great influence on the properties of CdSe quantum dots.

Compute the fidelity of photon cloning by constructing invariant subspaces

SUN Jinchuan

2022, 42(5):  468-473.  DOI: 10.3969/j.issn.1000-1565.2022.05.004

Asbtract ( 228 )   PDF (467KB) ( 152 )  

References | Related Articles | Metrics

The interaction between two-mode radiation field and several three-level atoms is studied. The variation of the average fidelity of photon cloning with time is calculated, and the numerical calculation is simplified. As for the numerical calculation of the evolution of quantum states, it is generally calculated in the whole Hilbert space. If the spatial dimension of the system is large, the numerical calculation needs to process a large amount of data and consumes a lot of calculation time. Sometimes the numerical calculation can be simplified according to the special physical properties of the system. If the invariant subspace of each quantum state is found in the whole Hilbert space, each quantum state will always evolve in its own invariant subspace under the action of the time-evolution operator. It is thus not necessary to numerically calculate the evolution of quantum states in the whole space, but only in the subspace where the initial state is located. Through comparative analysis, it is found that when numerically calculating the cloning of photons by a few three-level atoms, the amount of data to be processed when computing in the whole space is one order of magnitude larger than that in the all subspaces.

Study on visible light photocatalytic degradation of dibutyl phthalate in water

LEI Yuan, LIU Guisui, ZHU Aixue, LI Muyuan, LIU Pengyan

2022, 42(5):  474-482.  DOI: 10.3969/j.issn.1000-1565.2022.05.005

Asbtract ( 355 )   PDF (1283KB) ( 305 )  

References | Related Articles | Metrics

The composite material g-C₃N₄/Bi₄O₅I₂ was synthesized and characterized. The influencing factors of photocatalytic degradation of dibutyl phthalate(DBP)in water under visible light irradiation using the as-synthesized catalyst were studied, including catalyst dosage, initial solution concentration, pH and common anion Cl^-, NO^-₃ and SO^2-₄ in water. Through the analysis of degradation products, the possible degradation mechanism was proposed. The results showed that the optimum dosage of g-C₃N₄/Bi₄O₅I₂ was 0.6 g/L. The higher the initial concentration in the study range, the lower the degradation rate. When the solution was neutral, the photocatalytic degradation effect of DBP in water was the best. Cl^-, NO^-₃ and SO^2-₄ all inhibited the photocatalytic degradation to a certain extent. Through the analysis of the degradation products after the reaction, it is speculated that the side chain of DBP breaks first under the attack of active substances, and then continues to degrade into small molecular substances. The research results have important practical significance and reference value for the removal of phthalates in water environment. - DOI:10.3969/j.issn.1000-1565.2022.05.005可见光催化降解水中邻苯二甲酸二丁酯雷源¹,刘桂随²,朱爱雪²,李牧原²,刘芃岩¹(1.河北大学 生态环境学院(筹),河北 保定 071002;2.河北大学 化学与环境科学学院,河北 保定 071002)摘 要:合成了复合材料g-C₃N₄/Bi₄O₅I₂,并进行了表征分析,以其为催化剂,研究了可见光照射下,水中邻苯二甲酸二丁酯(DBP)光催化降解的影响因素:催化剂投加量、溶液初始浓度、pH及水中常见阴离子Cl^-、NO^-₃和SO^2-₄等,并通过对降解产物的分析,提出了可能的降解机理. 结果表明:g-C₃N₄/Bi₄O₅I₂的最佳投加量为0.6 g/L;在研究范围内初始浓度越高,降解率越低;当溶液为中性时,对水中DBP的光催化降解效果最好;Cl^-、NO^-₃和SO^2-₄都对光催化降解产生了一定的抑制作用. 通过对反应后降解产物的分析,推测DBP是在活性物质的攻击下,侧链先发生断裂,再继续降解为小分子物质. 研究结果对水环境中邻苯二甲酸酯类的去除具有重要的实际意义和参考价值. 关键词:可见光;邻苯二甲酸二丁酯;光催化降解;g-C₃N₄/Bi₄O₅I₂中图分类号:X703 文献标志码:A 文章编号:1000-1565(2022)05-0474-09Study on visible light photocatalytic degradation of dibutyl phthalate in water LEI Yuan¹, LIU Guisui², ZHU Aixue², LI Muyuan², LIU Pengyan¹(1. School of Eco-Environment, Hebei University, Baoding 071002,China; 2. College of Chemistry and Environmental Science, Hebei University, Baoding 071002,China)Abstract: The composite material g-C₃N₄/Bi₄O₅I₂ was synthesized and characterized. The influencing factors of photocatalytic degradation of dibutyl phthalate(DBP)in water under visible light irradiation using the as-synthesized catalyst were studied, including catalyst dosage, initial solution concentration, pH and common anion Cl^-, NO^-₃ and SO^2-₄ in water. Through the analysis of degradation products, the possible degradation mechanism was proposed. The results showed that the optimum dosage of g-C₃N₄/Bi₄O₅I₂ was 0.6 g/L. The higher the initial concentration in the study range, the lower the degradation rate. When the solution was neutral, the photocatalytic degradation effect of DBP in water was the best. Cl^-, NO^-₃ and SO^2-₄ all inhibited the photocatalytic degradation to a certain extent. Through the analysis of the degradation products after the reaction, it is speculated that the side chain of DBP breaks first under the attack of active substances, and then continues to degrade into small molecular substances. The research results have important practical significance and reference value for the removal of phthalates in water environment. - 收稿日期:2021-05-15 基金项目:国家自然科学基金资助项目(21377033);河北省自然科学基金资助项目(B2021201031) 第一作者:雷源(1997—),女,河北邢台人,河北大学在读硕士研究生,主要从事环境污染化学方向研究.E-mail:2317535846@qq.com 通信作者:刘芃岩(1964—),女,河北保定人,河北大学教授,博士生导师,主要从事环境中典型污染物的生成降解与迁移转化研究.E-mail:hbupyliu@163.com第5期雷源等:可见光催化降解水中邻苯二甲酸二丁酯

Classification of donkey meat and other meat based on nutrient compositions and principal component analysis

NIU Xiaoying, MU Xiaoqing, SUN Jie, ZHANG Chunjiang,ZHAO Zhilei, TIAN Te

2022, 42(5):  483-493.  DOI: 10.3969/j.issn.1000-1565.2022.05.006

Asbtract ( 472 )   PDF (1007KB) ( 293 )  

References | Related Articles | Metrics

Forty fresh donkey meat, and eight pork, eight beef and eight mutton samples were collected. Fat and protein in samples were determined by Soxhlet extraction and Kjeldahl method. Fatty acids were determined by gas chromatography, and amino acids were determined using an automatic amino acid analyzer with the method of cation exchange chromatography separation and ninhydrin post-column derivatization. One-way analysis of variance(ANOVA)was carried out, and fat, protein, tetradecanoic acid,- DOI:10.3969/j.issn.1000-1565.2022.05.006基于营养成分和主成分分析的驴肉与其他肉类分类研究牛晓颖¹,牟晓晴¹,孙杰^1,2,张春江²,赵志磊¹,田特¹(1.河北大学 质量技术监督学院,河北 保定 071002;2.中国农业科学院 农产品加工研究所,农业农村部农产品加工综合性重点实验室,北京 100193)摘 要:选取生鲜驴肉样品40个,生鲜猪肉、牛肉、羊肉样品各8个,使用索氏抽提法和凯氏定氮法分别检测了样品的肌间脂肪和蛋白质含量,采用气相色谱法检测了样品的多种脂肪酸,并使用阳离子交换色谱分离、茚三酮柱后衍生法对样品的多种氨基酸含量进行了检测.对驴肉和其他肉类样品的多种营养成分含量进行了单因素方差分析. 结果发现:脂肪、蛋白质、肉豆蔻酸、十五碳酸、棕榈酸、棕榈油酸、硬脂酸、亚油酸、油酸及总不饱和脂肪酸、总饱和脂肪酸具有极显著差异,二十四碳一烯酸、反式油酸、苏氨酸、丝氨酸、异亮氨酸、亮氨酸、赖氨酸、组氨酸和脯氨酸具有显著差异,门冬氨酸、谷氨酸、甘氨酸、丙氨酸、酪氨酸、精氨酸和总氨基酸具有一定差异.对不同差异水平指标组合分别进行了主成分分析,发现有明显的聚类趋势,其中极显著差异指标数据(多为风味成分)能够完全将驴肉和其他肉类分开.研究结果表明:使用营养成分对驴肉和其他肉类进行分类是可行的,不同肉类所具有的不同风味特征是分类的关键.关键词:驴肉;分类;营养成分;方差分析;主成分分析中图分类号:TS251.7 文献标志码:A 文章编号:1000-1565(2022)05-0483-11Classification of donkey meat and other meat based on nutrient compositions and principal component analysisNIU Xiaoying¹, MU Xiaoqing¹, SUN Jie^1,2, ZHANG Chunjiang²,ZHAO Zhilei¹, TIAN Te¹(1. College of Quality and Technical Supervision, Hebei University, Baoding 071002, China; 2. KeyLaboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs, Institute of FoodScience and Technology, Chinese Academy of Agricultural Sciences(CAAS), Beijing 100193, China)Abstract: Forty fresh donkey meat, and eight pork, eight beef and eight mutton samples were collected. Fat and protein in samples were determined by Soxhlet extraction and Kjeldahl method. Fatty acids were determined by gas chromatography, and amino acids were determined using an automatic amino acid analyzer with the method of cation exchange chromatography separation and ninhydrin post-column derivatization. One-way analysis of variance(ANOVA)was carried out, and fat, protein, tetradecanoic acid,- 收稿日期:2022-05-14 基金项目:河北省重点研发计划项目(21327108D) 第一作者:牛晓颖(1980—),女,河北清河人,河北大学副教授,博士,主要从事农产品和食品无损检测技术方向研究.E-mail: xiaoyingniu@126.com 通信作者:赵志磊(1977—),男,河北辛集人,河北大学教授,博士,主要从事食品质量和安全检测方向研究.E-mail: zhaozhilei-3208@163.com第5期牛晓颖等:基于营养成分和主成分分析的驴肉与其他肉类分类研究pentadecanoic acid, palmitic acid, palmitoleic acid, stearic acid, linoleic acid, oleic acid, total unsaturated fatty acid and total saturated fatty acid in donkey meat and other meat samples show statistically highly significant differences. Tetracosaenoic acid, elaidic acid, threonine, serine acid, isoleucine, leucine, lysine, histidine acid and proline, show significant differences. Aspartic acid, glutamic acid, glycine, lacid,phenylalanine, tyrosine, l-arginine, and total amino acids show difference. Principal component analysis was performed on the combinations of nutrient compositions at different significance levels, and obvious clustering tendencies for donkey meat and other meats samples were found. Donkey meat samples can be correctly identified by the first two principal component scores extracted from the nutrient compositions of the highly significant differences(mostly flavor components). The results indicate that the classification of donkey meat and other meats based on the nutrient compositions combination is feasible, flavor component is a crucial classificant factor.

Carbon-coated K_0.5Mn₂O_4.3·0.5H₂O as cathode for potassium-ion batteries

QIAN Jiaqi, LI Xiaoting, LEI Yu, ZHANG Wenming

2022, 42(5):  494-500.  DOI: 10.3969/j.issn.1000-1565.2022.05.007

Asbtract ( 288 )   PDF (1344KB) ( 194 )  

References | Related Articles | Metrics

Manganese oxide-based cathodes are attracting great interest owing to their advantages such as low cost, high capacity and energy density. Nevertheless, rapid capacity fading is a critical problem due to the direct contact between cathode and electrolyte, restraining its wide applications. To solve this problem, surface coating becomes a feasible strategy for the cathode material. A carbon coating layer with dopamine was introduced uniformly on the surface of K_0.5Mn₂O_4.3·0.5H₂O by solvothermal process. The coated carbon layer prohibits direct contact of electrode and the electrolyte to effectively hinders side reaction. At a current density of 50 mA/g, the discharge capacity of carbon-coated sample with 10%(wt.)dopamine(C@S-KMO-10%)is still as high as 89.8 mA·h/g with a capacity retention ratio of 63.4% after 100 cycles, showing improved cycling stability and superior rate capability. While the uncoated sample(S-KMO)delivers a discharge capacity of 68.8 mA·h/g - DOI:10.3969/j.issn.1000-1565.2022.05.007碳包覆钾离子电池正极材料K_0.5Mn₂O_4.3·0.5H₂O的研究钱佳琦¹,李小亭¹,雷宇²,张文明²(1.河北大学 质量技术监督学院,河北 保定 071002;2.河北大学 物理科学与技术学院,河北 保定 071002)摘 要:锰基氧化物正极材料具有低成本、高容量和高能量密度等优点,是钾离子电池正极材料研究的热点.然而,由于正极材料与电解液直接接触,发生副反应,导致容量迅速衰减,限制了它的广泛应用.为解决这一问题,对正极材料采用表面包覆的改性策略,以多巴胺为碳源,采用溶剂热法在K_0.5Mn₂O_4.3·0.5H₂O正极材料均匀地包覆碳涂层.碳包覆层阻止了正极材料与电解液的直接接触,有效地抑制了副反应.结果发现:在电流密度为50 mA/g的条件下,添加占正极材料质量10%的多巴胺时,放电容量为89.8 mA·h/g,容量保持率为63.4%,表现出优异的电化学性能,而未包覆的正极材料的放电容量为68.8 mA·h/g, 循环100圈后容量保持率为32%.这种表面涂层策略为提高钾离子电池阴极的循环稳定性提供了一种新的改性方法.关键词:溶剂热法;碳包覆;正极材料;表面改性中图分类号:O646 文献标志码:A 文章编号:1000-1565(2022)05-0494-07Carbon-coated K_0.5Mn₂O_4.3·0.5H₂O as cathode for potassium-ion batteriesQIAN Jiaqi¹, LI Xiaoting¹, LEI Yu², ZHANG Wenming²(1. College of Quality and Technical Supervision, Hebei University, Baoding 071002, China;2. College of Physics Science and Technology, Hebei University, Baoding 071002, China)Abstract: Manganese oxide-based cathodes are attracting great interest owing to their advantages such as low cost, high capacity and energy density. Nevertheless, rapid capacity fading is a critical problem due to the direct contact between cathode and electrolyte, restraining its wide applications. To solve this problem, surface coating becomes a feasible strategy for the cathode material. A carbon coating layer with dopamine was introduced uniformly on the surface of K_0.5Mn₂O_4.3·0.5H₂O by solvothermal process. The coated carbon layer prohibits direct contact of electrode and the electrolyte to effectively hinders side reaction. At a current density of 50 mA/g, the discharge capacity of carbon-coated sample with 10%(wt.)dopamine(C@S-KMO-10%)is still as high as 89.8 mA·h/g with a capacity retention ratio of 63.4% after 100 cycles, showing improved cycling stability and superior rate capability. While the uncoated sample(S-KMO)delivers a discharge capacity of 68.8 mA·h/g - 收稿日期:2022-03-09 基金项目:国家自然科学基金资助项目(52171206) 第一作者:钱佳琦(1995—),女,河北保定人,河北大学在读硕士研究生,主要从事钾离子电池正极材料方向研究. E-mail:qianjiaqi6953@163.com 通信作者:张文明(1982—),男,吉林四平人,河北大学教授,主要从事新型离子电池、电催化锌空气电池、微生物燃料电池、可穿戴柔性传感器件方向研究.E-mail:wmzhang@hbu.edu.cn第5期钱佳琦等:碳包覆钾离子电池正极材料K_0.5Mn₂O_4.3·0.5H₂O的研究with 32% capacity retention after 100 cycles. This surface coating strategy offers a new modification approach to improve the cycling stability of cathodes for potassium ion batteries.

One new record species of the genus Triplax (Coleoptera: Erotylidae)from China

YAN Zihan, HOU Jialin, ZANG Haoming, WANG Haishan, LI Jing

2022, 42(5):  501-503.  DOI: 10.3969/j.issn.1000-1565.2022.05.008

Asbtract ( 312 )   PDF (452KB) ( 264 )  

References | Related Articles | Metrics

One species, Triplax amoena Solsky,1871 of the family Erotylidae is reported from China for the first time. The description and illustration are given. All studied specimens are deposited in the Biological Control Laboratory, College of Plant Protection, Hebei Agricultural University.

Effect of ultrasonic on mouse behavior and its mechanism in rodent repeller

SHAO Jianze, WEI Mengyi, CHEN Kai, ZHANG Yuming, LIU Fengsong

2022, 42(5):  504-510.  DOI: 10.3969/j.issn.1000-1565.2022.05.009

Asbtract ( 762 )   PDF (1017KB) ( 836 )  

References | Related Articles | Metrics

In order to explore the effect of ultrasonic on mouse behavior and the mechanism of action of ultrasonic mouse repellent, a simple method for evaluating the effect of ultrasonic mouse repellent was established, which employed a commercially ultrasonic rodent repeller to investigate its effect on repelling mice in an open field.The spontaneous activity,elevated plus maze, and the sucrose water preference experiment were used to count the behavioral changes of mice under the stress of ultrasonic generator and ultrasonic mouse repellent. Results showed that the rodent repellent could drive away the mice during 10 d experiments. Continuous 10 d treatment with the ultrasonic repellent can cause the mice to decline in their ability to move and explore, induce anxiety and depression, and the above-mentioned changes caused by the ultrasonic generator treatment are more significant. This study can provide data support for the mechanism of ultrasonic repellent. It can also provide technical reference for the effect evaluation and research and development of related mouse repellents.

Prokaryotic expression,purification and biological activity identification of recombinant human leptin protein

ZHOU Xiangyang, LI Zhongkai, HAO Tengfei, DING Guangshuo, ZHENG Wenhui, LI Wenjuan

2022, 42(5):  511-518.  DOI: 10.3969/j.issn.1000-1565.2022.05.010

Asbtract ( 351 )   PDF (852KB) ( 253 )  

References | Related Articles | Metrics

To avoid the formation of inclusion bodies and the low yield caused by protein aggregation in the process of refolding in vitro, during the large-scale production of recombinant human leptin protein(hLeptin), the high-level soluble expression of hLeptin in Escherichia coli was investigated, and the biological activity was detected. The fusion expression plasmid pET-30a(+)-SUMO-Lep was constructed by using the coding sequence of mature peptide of hLeptin and pET-30a(+)-SUMO system, which was transformed into E.coli BL21(DE3)and was induced by isopropyl-β-D-thiogalactose(IPTG). Afterwards, the recombinant protein was purified by Ni metal affinity chromatography, and the mature hLeptin- DOI:10.3969/j.issn.1000-1565.2022.05.010重组人瘦素蛋白的原核表达、纯化和生物学活性鉴定周向阳^1,2,李仲凯³,郝腾飞³,丁光硕⁴,郑文慧¹,李文娟^1,2(1.河北大学 基础医学院,河北 保定 071000;2.河北省炎性自身免疫性疾病发病机制及防治重点实验室,河北 保定 071000;3.河北农业大学 生命科学学院,河北 保定 071001;4.河北大学 公共卫生学院,河北 保定 071000)摘 要:为解决重组人瘦素蛋白(hLeptin)大规模生产过程中包涵体的形成以及体外重折叠过程中蛋白聚集导致的低产量,探究在大肠杆菌中hLeptin高水平可溶性的表达,并进行生物学活性检测.利用hLeptin成熟肽基因与pET-30a(+)-SUMO系统构建融合表达质粒pET-30a(+)-SUMO-Lep,转化至大肠杆菌BL21(DE3),加入异丙基-β-D-硫代半乳糖(IPTG)进行诱导表达,之后经Ni金属亲和层析纯化,并切去SUMO融合标签后获得成熟hLeptin.重组hLeptin表达量高,主要以可溶形式存在.通过KM小鼠减肥实验和CCK8实验证明重组hLeptin具有生物学活性.综上,使用SUMO融合标签,以增强hLeptin在大肠杆菌中的高效可溶性高纯度的表达,为大规模生产hLeptin提供了一种新方法,同时为表达可溶性重组蛋白研究提供了一定的基础.关键词:重组hLeptin;SUMO;原核表达;生物学活性中图分类号:Q78 文献标志码:A 文章编号:1000-1565(2022)05-0511-08Prokaryotic expression,purification and biological activity identification of recombinant human leptin proteinZHOU Xiangyang^1,2, LI Zhongkai³, HAO Tengfei³, DING Guangshuo⁴, ZHENG Wenhui¹, LI Wenjuan^1,2(1.School of Basic Medicine Sciences, Hebei University, Baoding 071000, China;2.Key Laboratory of Pathogenesis Mechanism and Control of Inflammatory Autoimmune Diseases in Hebei Province, Baoding 071000, China;3.College of Life Sciences, Hebei Agricultural University, Baoding 071001, China;4.College of Public Health, Hebei University, Baoding 071000, China)Abstract: To avoid the formation of inclusion bodies and the low yield caused by protein aggregation in the process of refolding in vitro, during the large-scale production of recombinant human leptin protein(hLeptin), the high-level soluble expression of hLeptin in Escherichia coli was investigated, and the biological activity was detected. The fusion expression plasmid pET-30a(+)-SUMO-Lep was constructed by using the coding sequence of mature peptide of hLeptin and pET-30a(+)-SUMO system, which was transformed into E.coli BL21(DE3)and was induced by isopropyl-β-D-thiogalactose(IPTG). Afterwards, the recombinant protein was purified by Ni metal affinity chromatography, and the mature hLeptin- 收稿日期:2022-03-02 基金项目:河北省自然科学基金资助项目(H2019201084);河北大学医学学科培育项目(2021A01);河北大学大学生创新创业项目(2022309) 第一作者:周向阳(1997—),男,山西大同人,河北大学在读硕士研究生,主要从事肿瘤代谢及化学预防的研究.E-mail: zxy9708@163.com 通信作者:李文娟(1977—),女,甘肃静宁人,河北大学副教授,博士,主要从事肿瘤代谢研究.E-mail: liwenjuan@hbu.edu.cn第5期周向阳等:重组人瘦素蛋白的原核表达、纯化和生物学活性鉴定was obtained after cutting off the SUMO fusion tag. The recombinant hLeptin was highly expressed and mainly existed in soluble form. The biological activity was confirmed by KM mouse Weight-Losing Test and the CCK8 assay. In this study, we employed the SUMO fusion tag to increase the solubility and the purity of hLeptin expression in E. coli, which could provide a novel method for large-scale production of leptin and lay a foundation for the expression of soluble recombinant protein.

Effect of IAA on the growth and photosynthetic characteristics of Quercus sessilis at seedling stage

SHI Haiyan, ZHANG Zhigang, LI Hong,YANG Jianjun, LI Bin, SHI Kaiqi, YANG Lu

2022, 42(5):  519-529.  DOI: 10.3969/j.issn.1000-1565.2022.05.011

Asbtract ( 367 )   PDF (1148KB) ( 314 )  

References | Related Articles | Metrics

The phenomenon of topping out exists during the growth and development of young Quercus sessilis. In order to investigate the effect of spraying different mass concentrations of the exogenous plant growth regulator indole-3-acetic acid(IAA)on the growth and photosynthetic characteristics- DOI:10.3969/j.issn.1000-1565.2022.05.011IAA对幼苗期夏橡生长及光合特性的影响石海燕¹,张志刚²,李宏²,杨建军¹,李斌³,史开奇³,杨璐^4,5(1.新疆大学 生态与环境学院,绿洲生态教育部重点实验室,新疆 乌鲁木齐 830017;2.新疆林科院 造林治沙研究所,新疆 乌鲁木齐 830000;3.伊犁州林木良种繁育试验中心,新疆 察布查尔 835311;4.新疆林果树种选育与栽培重点实验室,新疆 乌鲁木齐 830000;5.新疆林木资源与利用国家林草局重点实验室,新疆 乌鲁木齐 830000)摘 要:幼苗期夏橡在生长发育过程中存在封顶现象,为探究外源植物生长调节剂吲哚乙酸(indole-3-acetic acid,IAA)对封顶现象的破除作用,以1年生夏橡播种苗木为研究对象,在夏橡封顶时喷施不同质量浓度的IAA.通过对夏橡生长特性、光合特性的测定,运用最小显著性差异法(least significant difference,LSD)及沃勒-邓肯对比分析在喷施不同质量浓度IAA后幼苗期夏橡生长特性与叶片光合性能的差异,结果表明:喷施IAA提高了夏橡光合特性日变化指标G_s、T_r及C_i,进而提高了植株的净光合速率(P_n),低质量浓度IAA处理下幼苗期夏橡P_n下午峰值提前,高质量浓度处理后光合“午休”现象消失;IAA处理对于延缓P_n下降有一定作用,质量浓度为60 mg/L的IAA处理时P_n最大;IAA处理前期主要受气孔限制,后期以非气孔限制为主.得出结论:IAA的喷施会提高夏橡幼苗的P_n,延缓P_n的下降,此外IAA质量浓度为100~120 mg/L时,破除幼苗期夏橡封顶现象效果最显著.关键词:幼苗期夏橡;封顶现象;IAA;光合特性中图分类号:Q145.1 文献标志码:A 文章编号:1000-1565(2022)05-0519-11Effect of IAA on the growth and photosynthetic characteristics of Quercus sessilis at seedling stageSHI Haiyan¹, ZHANG Zhigang², LI Hong²,YANG Jianjun¹, LI Bin³, SHI Kaiqi³, YANG Lu^4,5(1.Key Laboratory of Oasis Ecology of Education Ministry, College of the Ecology and Environment, Xinjiang University, Urumqi 830017, China; 2.Institute of Afforestation and Sand Control, Xinjiang Academy of Forestry Sciences, Urumqi 830000, China; 3.Yill Trees Variety Breeding Center of Xinjiang Uygur Autonomous Region, Chabchal 835311, China; 4.Key Laboratory of Fruit Tree Species Breeding and Cultivation in Xinjiang, Urumqi 830000, China; 5.Key Laboratory of Forest Resources and Utilization in Xinjiang of National Forestry and Grassland Administration, Urumqi 830000, China)Abstract: The phenomenon of topping out exists during the growth and development of young Quercus sessilis. In order to investigate the effect of spraying different mass concentrations of the exogenous plant growth regulator indole-3-acetic acid(IAA)on the growth and photosynthetic characteristics- 收稿日期:2022-03-25 基金项目:伊犁州林木良种繁育试验中心国家杨树、白榆重点林木良种基地补助项目(202110);新疆林草科技专项(XJLCKJ2022008) 第一作者:石海燕(1998—),女,河北邢台人,新疆大学在读硕士研究生,主要从事生态修复与可持续发展研究. E-mail: shihaiyan_ecology@163.com 通信作者:杨建军(1978—),男,新疆乌苏人,新疆大学副教授,博士,主要从事干旱区水土保持与荒漠化防治研究. E-mail: yjj@xju.edu.cn第5期石海燕等:IAA对幼苗期夏橡生长及光合特性的影响of Q. sessilis, this paper used 1-year-old Q. sessilis sown seedlings as the research object, and IAA sprayed at different mass concentrations when the Q. sessilis were topped out. By measuring the growth characteristics and photosynthetic characteristics of Q. sessilis, the differences in growth characteristics and photosynthetic performance of Q. sessilis leaves at the seedling stage after spraying different concentrations of IAA were compared and analyzed using least significant difference(LSD)and Waller-Duncan comparisons. The results showed that the daily changes of G_s、T_r and C_i in photosynthetic characteristics of Q. sessilis were increased by IAA spraying, which in turn increased the photosynthetic rate(P_n )of the plants, and the afternoon peak of P_n in Q. sessilis at the seedling stage was advanced under the low mass concentration of IAA treatment, and the photosynthetic “lunch break” phenomenon disappeared after the high mass concentration treatment. Which had a certain effect on delaying the decrease of. P_n was maximum at the IAA treatment with a mass concentration of 60 mg/L. The IAA treatment was mainly stomatal-limited in the early stages and non-stomatal-limited in the later stages. It was concluded that the application of IAA increased the P_n of Q. sessilis seedlings and delayed the decrease of P_n. In addition, IAA at a mass concentration of 100~120 mg/L was the most effective in breaking the Q. sessilis topping phenomenon at the seedling stage.

Performance assessment and parameter optimization of an internal model PI controller in frequency and time domains

LI Shizhe, LIU Chang

2022, 42(5):  530-541.  DOI: 10.3969/j.issn.1000-1565.2022.05.012

Asbtract ( 385 )   PDF (1058KB) ( 215 )  

References | Related Articles | Metrics

Because the performance degradation of the control system is usually related to the unreasonable parameters of the PI controller, and the single performance assessment index in time domain is not accurate, therefore a performance assessment method based on the combination of frequency domain and time domain is presented for the control object with pure delay characteristic,which overcomes the inaccuracy of a single performance metric. Under different control strategies and parameters, the distance between the system performance index and the reference curve or reference point is analyzed. For two typical high-order processes, different reduced-order models are given, and the model with the best fitting characteristics is applied to the design of internal model PI controller. Based on the results of frequency-domain and time-domain assessment, a method of re-optimizing and tuning the parameters of PI controller is presented, which is used to improve the performance of the control system,and it is realized by re-setting the parameters through the data-driven method. The structure is simple, and the operation efficiency is improved.- DOI:10.3969/j.issn.1000-1565.2022.05.012基于频域和时域的内模PI控制器性能评价与参数优化李士哲,刘畅(华北电力大学 控制与计算机工程学院,河北 保定 071003)摘 要:由于控制系统的性能降低通常与比例积分(proportion integration,简称PI)控制器不合理的参数有关,而且单一的时域性能评价指标不准确,因此,针对具有纯迟延特性的控制对象,给出了基于频域和时域相结合的性能评价方法,克服了单一性能指标的不准确性.在不同控制策略和参数下,分析了系统性能指标与基准曲线或基准点的距离.针对2个典型的高阶被控过程,分别给出了不同的降阶模型,并把拟合对象特性最好的模型用于内模PI控制器的设计.基于频域和时域评价的结果,给出了PI控制器参数重新优化和整定的方法,用于改善控制系统的性能,该方法通过数据驱动方法对参数进行重新整定来实现,提高了运算效率.仿真实验验证了上述性能评价和参数优化方法的有效性.关键词:性能评价;PI控制器;频域指标;时域指标;参数优化中图分类号:TP273 文献标志码:A 文章编号:1000-1565(2022)05-0530-12Performance assessment and parameter optimization of an internal model PI controller in frequency and time domainsLI Shizhe, LIU Chang(School of Control and Computer Engineering, North China Electric Power University, Baoding 071003, China)Abstract: Because the performance degradation of the control system is usually related to the unreasonable parameters of the PI controller, and the single performance assessment index in time domain is not accurate, therefore a performance assessment method based on the combination of frequency domain and time domain is presented for the control object with pure delay characteristic,which overcomes the inaccuracy of a single performance metric. Under different control strategies and parameters, the distance between the system performance index and the reference curve or reference point is analyzed. For two typical high-order processes, different reduced-order models are given, and the model with the best fitting characteristics is applied to the design of internal model PI controller. Based on the results of frequency-domain and time-domain assessment, a method of re-optimizing and tuning the parameters of PI controller is presented, which is used to improve the performance of the control system,and it is realized by re-setting the parameters through the data-driven method. The structure is simple, and the operation efficiency is improved.- 收稿日期:2022-02-18 基金项目:深圳市可持续发展科技专项项目(KCXFZ20201221173402007 ) 第一作者:李士哲(1981—),男,河北保定人,华北电力大学(保定)讲师,博士,主要从事控制系统性能评价方向研究.E-mail:lishizhe121@163.com 通信作者:刘畅(1999—),女,河北保定人,华北电力大学(保定)在读硕士研究生,主要从事控制系统性能评价及故障诊断方向研究.E-mail:1432497470@qq.com第5期李士哲等:基于频域和时域的内模PI控制器性能评价与参数优化The simulation results verify the effectiveness of the above methods.

Segmentation algorithm of brain tumor MR images based on receptor field amplification and attentional mechanism

ZHENG Wei, ZHAO Jinfang, ZHANG Yijing, LIU Shuaiqi, ZHANG Xiaodan, MA Zepeng

2022, 42(5):  542-551.  DOI: 10.3969/j.issn.1000-1565.2022.05.013

Asbtract ( 415 )   PDF (1558KB) ( 201 )  

References | Related Articles | Metrics

Although the current full convolutional neural network has been able to accurately identify the location of brain tumors in the brain tumor segmentation task, there are still problems of low segmentation accuracy due to limited receptive field and information loss. To solve these problems, this paper proposes a U-Net brain tumor MR image segmentation algorithm based on receptive field amplification and attentional mechanism. Firstly, the receptive field block(RFB)is introduced into the U-Net network to increase the receptive field of the network, which solves the problem of low segmentation accuracy caused by the limited receptive field. In addition, an efficient channel attention module(ECA)is introduced to increase the networks response to useful features and suppress redundant features in the network. The MR brain tumor image data provided by the BRATS(the brain tumor image segmentation- DOI:10.3969/j.issn.1000-1565.2022.05.013基于感受野扩增和注意力机制的U-Net脑肿瘤MR图像分割郑伟¹,赵金芳¹,张奕婧¹,刘帅奇¹,张晓丹²,马泽鹏²(1. 河北大学 电子信息工程学院,河北 保定 071002;2. 河北大学附属医院 超声诊断科,河北 保定 071000)摘 要:针对U-Net网络感受野受限以及信息丢失导致的分割精度低的问题,提出了一种基于感受野扩增和注意力机制的U-Net脑肿瘤MR图像分割算法.首先,在U-Net网络中引入感受野模块(receptive field block,RFB)来增大网络的感受野,解决了网络由于感受野受限带来的分割精度低的问题.此外在网络中引入有效的通道注意模块(efficient channel attention,ECA)来增加网络对有用特征的响应,抑制网络中的冗余特征.使用BraTS(the brain tumor image segmentation challenge)提供的脑肿瘤MR图像数据对本文算法进行测试,用Dice相似性系数等指标进行评价,结果显示在完整肿瘤、核心肿瘤以及增强肿瘤的Dice值分别可达到0.86、0.86、0.79.与U-Net模型以及其他的网络相比得到了提高.实验结果表明,本文提出的算法能够有效提升脑肿瘤分割的精度,具有良好的分割性能.关键词:脑肿瘤分割;U-Net;RFB;注意力机制 中图分类号:TN911 文献标志码:A 文章编号:1000-1565(2022)05-0542-10Segmentation algorithm of brain tumor MR images based on receptor field amplification and attentional mechanismZHENG Wei¹, ZHAO Jinfang¹, ZHANG Yijing¹, LIU Shuaiqi¹, ZHANG Xiaodan², MA Zepeng²(1. College of Electronic and Information Engineering, Hebei University, Baoding 071002, China; 2. Department of Ultrasonography, Affilicated Hospital of Hebei University, Baoding 071000, China )Abstract: Although the current full convolutional neural network has been able to accurately identify the location of brain tumors in the brain tumor segmentation task, there are still problems of low segmentation accuracy due to limited receptive field and information loss. To solve these problems, this paper proposes a U-Net brain tumor MR image segmentation algorithm based on receptive field amplification and attentional mechanism. Firstly, the receptive field block(RFB)is introduced into the U-Net network to increase the receptive field of the network, which solves the problem of low segmentation accuracy caused by the limited receptive field. In addition, an efficient channel attention module(ECA)is introduced to increase the networks response to useful features and suppress redundant features in the network. The MR brain tumor image data provided by the BRATS(the brain tumor image segmentation- 收稿日期:2021-06-11 基金项目:河北省自然科学基金资助项目(F2020201025;H2020201021);河北省高等学校科学技术研究项目(BJ2020030) 第一作者:郑伟(1972—),女,黑龙江兰西人,河北大学教授,博士,主要从事图像处理与分析、图像安全通信、图像加密和隐藏方向研究.E-mail:147685650@qq.com 通信作者:张晓丹(1989—),女,河北承德人,河北大学附属医院主治医师,主要从事常规疾病及肿瘤病变的影像诊断.E-mail:zxd201505@126.com第5期郑伟等:基于感受野扩增和注意力机制的U-Net脑肿瘤MR图像分割challenge)was used to test the method, and indexes such as Dice similarity coefficient were used to evaluate the method. The results showed that the Dice of intact tumor, core tumor and enhanced tumor could reach 0.86, 0.86 and 0.79 respectively. Compared with the U-Net model and other networks, this method is improved. The results show that the proposed method can effectively improve the accuracy of brain tumor segmentation and has good segmentation performance.

A network intrusion detection method based on SSA-BRF

WEI Mingjun, ZHANG Xinnan, LIU Yazhi, ZHOU Taiyu

2022, 42(5):  552-560.  DOI: 10.3969/j.issn.1000-1565.2022.05.014

Asbtract ( 320 )   PDF (916KB) ( 265 )  

References | Related Articles | Metrics

In order to solve the problem that the selection of hyper-parameters of random forest(RF)will have a great impact on the classification results of RF, an optimization method of RF hyper-parameters based on sparrow search algorithm(SSA)is proposed to help RF find a set of excellent hyper-parameters. Balanced random forest(BRF)is used to solve the problem that RF is difficult to accurately identify minority data, so as to improve the recall rate of the model for minority data. Finally, SSA-BRF model is constructed by integrating SSA and BRF, and the classification effect of the model is verified in CIC-IDS-2017 data set. Experimental results show that compared with RF, the accuracy, macro recall and macro F1 score of SSA-BRF are improved by 9.57%, 26.62% and 0.17 respectively. This model can improve the performance of network intrusion detection system to a certain extent.