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Effects of water application intensity of micro-sprinkler irrigation and soil salinity on environment of coastal saline soils

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Water Science and Engineering 2020年第2期13卷 116-123页

作者： Lin-lin Chu Yao-hu kang Shu-qin Wan College of Agricultural Science and Engineering Hohai UniversityNanjing 210098China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

To achieve the greatest leaching efficiency,water movement must occur under unsaturated flow ***,the water application intensity of irrigation must be chosen *** aim of this study was to evaluate the impact of the water application intensity of micro-sprinkler irrigation on coastal saline soil with different salt *** achieve this objective,a laboratory experiment was conducted with three soil salinity treatments(2.26,10.13,and 22.29 dS/m)and three water application intensity treatments(3.05,5.19,and 7.23 mm/h).The results showed that the effect of soil salinity on soil water content,electrical conductivity,and pH was significant,and the effect of the water application intensity was *** soil water content was present in the 40e60 cm profile in all soil salinity treatments,and the content was higher in the medium and high water application intensity treatments than in the low-intensity *** salt leaching occurred in all treatments,and the effect was stronger in the high soil salinity treatment and medium water application intensity *** the medium and high soil salinity treatments,pH exhibited a decreasing trend,with no trend change in the low soil salinity treatment,and the pH value was higher in the medium water application intensity treatment than in the other two *** results indicated that the three intensities evaluated had no statistically different effect on the electrical conductivity of saturated soil-paste extracts(EC)in the upper 20 cm of the soil profile,and it would be better to maintain a lower value of the water application intensity.

关键词： Soil water content Salinity Micro-sprinkler irrigation Water application intensity Saline soil environment

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Influences of different crossing types on dynamic response of underground cavern subjected to ground shock

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Defence Technology（防务技术） 2021年第4期17卷 1555-1571页

作者： Shao-liu Liu Yue-tang Zhao kang hu Shi-hao Wang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjingJiangsu210007China

An intersecting cavern is a common structural form used in underground engineering,and its safety and stability performance directly control the service performance of the whole *** dynamic responses of the three kinds of crossing type(+-shaped,T-shaped,L-shaped)caverns subjected to ground shock were studied by numerical *** velocity plus force mode boundary setting method was proposed in the coupled static and dynamic analysis of a deep underground *** results show that,among the three types of crossing caverns,the+-shaped cavern is the most significantly affected by the dynamic action,followed by T-shaped,and then L-shaped *** vault settlement,straight wall deformation,vault peak particle velocity,effective plastic strain of surrounding rock,and maximum principal stress and strain at the bottom of the lining of the straight wall increase with the increase of cavern *** vault settlement,straight wall deformation,effective plastic strain of surrounding rock,and the maximum principal stress and strain at the bottom of lining to the straight wall decrease with the increase of lateral pressure coefficient,and the peak particle velocity at the vault *** variation is small compared with the change of cavern *** influence range of the underground cavern intersection is two cavern diameters from the intersection *** bottom of the straight wall at the intersection is the weak *** is suggested to thicken the support locally to improve the stability of the cavern.

关键词： Intersecting cavern Ground shock Initial ground stress Dynamic response

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Pressure-induced structure,electronic,thermodynamic and mechanical properties of Ti_(2)AlNb orthorhombic phase by first-principles calculations

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Rare Metals 2021年第10期40卷 2964-2974页

作者： Zhen-Yi Wei kang-Ming hu Bai-Sheng Sa Bo Wu Multiscale Computational Materials Facility School of Materials Science and EngineeringFuzhou UniversityFuzhou 350100China

Effects of pressure on lattice parameters, electronic, thermodynamic and mechanical properties of the fully ordered Ti_(2)AlNb orthorhombic phase were studied using first-principles calculations based on density functional theory(DFT). The bonding nature for ordering orthorhombic Ti_(2)AlNb was revealed quantitatively through the electronic structure analyzing. The external pressures play limited roles in the elastic anisotropy of the alloy due to the outstanding dynamical and mechanical stabilities under pressure. However, the shear modulus of O phase manifests anisotropic, where {010} shear planes are the easiest planes to cleave among the principal planes under all *** heat capacities, volume expansions and thermal expansion coefficients were calculated using the quasi-harmonic approximation model based on the phonon dispersion curves. Meanwhile, the bulk modulus, Young’s modulus,shear modulus and the hardness are promptly enhanced under pressure. The predicted results give hints to design Ti_(2)AlNb-based alloy as high-pressure applications.

关键词： Ti2AlNb-based orthorhombic phase Pressure-induced effect Thermodynamic properties Mechanical properties First-principles calculations

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Effect of titanium on the wettability between Fe-P-Ti alloy and Al2O3 substrate

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Progress in Natural Science:Materials International 2024年第3期34卷 555-561页

作者： Rui Wang Shengjie Bai Xu Chen Likui Xie Zhiqiang Yu Yang kang Yihong Li Yong hu Zhiyue Shi Zhijie Yan School of Materials Science and Engineering North University of China Shanxi Key Laboratory of Advanced Metal Materials for Special Environments North University of China CISDI Engineering CO. LTD. School of Materials Science and Engineering Taiyuan University of Science and Technology

It is of significance that the wettability between the molten alloy and the Al2O3affects the inclusion removal,nozzle clogging and refractory erosion. In the present work, the wettability between the Al2O3substrate and Fe–P–Ti alloys with different Ti content was investigated by using the sessile droplets method. The interfacial characteristics were investigated by scanning electron microscope（SEM）. The contact angles between the sintered Al2O3substrate and Fe–P–Ti alloys with 0, 0.05, 0.10 and 0.15 wt% Ti are 100.1°, 97.3°, 94.5°and 90.5°,respectively. The oxidation of [Al] and [Ti] in the molten alloys leads to the formation of the oxides on the droplets. With the increase of Ti content in the Fe–P–Ti alloys, the formed oxides change from Al2O3to Ticontaining oxides. The reaction between [Ti] and Al2O3substrate in the interface results in the formation of Ti-containing oxides. The quantity of the interfacial oxides increases with the increase of Ti content in the *** a result, the synergetic effect of the formation of the interfacial products and the oxides on the surface of droplets leads to the decrease of the contact angles between the Al2O3substrate and Fe–P–Ti alloys due to the increase of Ti content.

关键词： Al2O3 substrate Contact angle Fe–P–Ti alloys Interfacial reaction Wettability

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Aptamers Against Viral Hepatitis:from Rational Design to Practical Application

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Virologica Sinica 2008年第5期23卷 315-320页

作者： hui FENG kang-hong hu State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071China Institute of Molecular and Cellular Anatomy University of Regensburg Regensburg D-93053 Germany

Aptamers are short nucleic acids or peptides that strongly bind to a protein of interest and functionally inhibit a given target protein at the intracellular level. Besides high affinity and specificity, aptamers have several advantages over traditional antibodies. Hence, they have been broadly selected to develop antiviral agents for therapeutic applications against hepatitis B and C viruses (HBV, HCV). This review provides a summary of in vitro selection and characterization of aptamers against viral hepatitis, which is of practical significance in drug discovery.

关键词：病毒性肝炎临床分析治疗方法抵抗力

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Structural Characteristics and Molecular Mechanism of Hepatitis B Virus Reverse Transcriptase

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Virologica Sinica 2009年第6期24卷 509-517页

作者： hui FENG kang-hong hu State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071China

Hepatitis B virus (HBV), a typical member of the Hepadnaviridae family, is responsible for infections that cause B-type hepatitis which leads to severe public health problems around the world. The small enveloped DNA-containing virus replicates via reverse transcription, and this unique process is accomplished by the virally encoded reverse transcriptase (RT). This multi-functional protein plays a vital role in the viral life cycle. Here, we provide a summary of current knowledge regarding the structural characteristics and molecular mechanisms of HBV RT. Improved understanding of these processes is of both theoretical and practical significance for fundamental studies of HBV and drug discovery.

关键词：乙型肝炎病毒分子机理结构特征和逆转录病毒逆向家庭成员健康问题

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Effects of water application intensity of microsprinkler irrigation on water and salt environment and crop growth in coastal saline soils

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Journal of Integrative Agriculture 2015年第10期14卷 2077-2089页

作者： Chu Lin-lin kang Yao-hu WAN Shu-qin National Research Center of Pumps Jiangsu University Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences

Laboratory and field experiments were conducted to investigate the effects of water application intensity（WAI） on soil salinity management and the growth of Festuca arundinacea（festuca） under three stages of water and salt management strategies using microsprinkler irrigation in Hebei Province, North China. The soil water content（è） and salinity of homogeneous coastal saline soils were evaluated under different water application intensities in the laboratory experiment. The results indicated that the WAI of microsprinkler irrigation influenced the è, electrical conductivity（ECe） and p H of saline soils. As the WAI increased, the average values of è and ECe in the 0–40 cm profile also increased, while their average values in the 40–60 cm profile decreased. The p H value also slightly decreased as depth increased, but no significant differences were observed between the different treatments. The time periods of the water redistribution treatments had no obvious effects. Based on the results for è, ECe and p H, a smaller WAI was more desirable. The field experiment was conducted after being considered the results of the technical parameter experiment and evaporation, wind and leaching duration. The field experiment included three stages of water and salt regulation, based on three soil matric potentials（SMP）, in which the SMP at a 20-cm depth below the surface was used to trigger irrigation. The results showed that the microsprinkler irrigation created an appropriate environment for festuca growth through the three stages of water and salt regulation. The low-salinity conditions that occurred at 0–10 cm depth during the first stage（-5 k Pa） continued to expand through the next two stages. The average p H value was less than 8.5. The tiller number of festuca increased as SMP decreased from the first stage to the third stage. After the three stages of water and salt regulation, the highly saline soil gradually changed to a low-saline soil. Overall, based on the salt desa

关键词： coastal saline soil microsprinkler irrigation water application intensity soil salinity water and salt regulation reclamation

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Effect of different water application intensity and irrigation amount treatments of microirrigation on soil-leaching coastal saline soils of North China

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Journal of Integrative Agriculture 2016年第9期15卷 2123-2131页

作者： Chu Lin-lin kang Yao-hu WAN Shu-qin Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil-Water Environment in Southern China Ministry of Education/College of Water Conservancy and Hydropower Engineering Hohai University Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences

In coastal regions, Bohai Gulf is one of the most affected areas by salinization. To study the effects of mocrosprinkler irrigation on the characteristics of highly saline sandy loam soil（ECe（saturated paste extract）=22.3 d S m^–1; SAR（sodium adsorption ratio）=49.0） of North China, a laboratory experiment was conducted. Five water application intensity（WAI） treatments（1.7, 3.1, 5.3, 8.8, and 10.1 mm h^–1）, five irrigation amount（IA） treatments（148, 168, 184, 201, and 223 mm） and three time periods of water redistribution（0, 24 and 48 h） were employed in the study. A compounding microsprinkler system was used for the WAI treatments, and a single microsprinkler was used for the IA treatments. The results indicated that, as soil depth increased, soil water content（θ） increased and then slightly decreased; with WAI and IA consistently increasing, the relatively moist region expanded and the average θ increased. Meanwhile, soil ECe increased as soil depth increased, and the zone with low soil salinity expanded as WAI and IA increased. Although the reduction of the average SAR was smaller than that of the average electrical conductivity of the ECe, these variables decreased in similar fashion as WAI and IA increased under microsprinkler irrigation. The average p H decreased as soil depth increased. Longer time periods of water redistribution led to lower salinity and slight expansion of the SAR zone. Considering the effects of leached salts in coastal saline soils, greater WAI and IA values are more advantageous under unsaturated flow conditions, as they cause better water movement in the soil. After leaching due to microsprinkler irrigation, highly saline soil gradually changes to moderately saline soil. The results provide theoretical and technological guidance for the salt leaching and landscaping of highly saline coastal environments.

关键词： coastal saline soil microsprinkler irrigation SAR reclamation

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Influence of Slope and Slenderness Ratio on the Non-Column Volume in Skew Rolling

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Journal of Materials Science & Technology 2003年第Z1期19卷 192-194页

作者： Yongqiang kang Zhenghuan hu Jinping LIU Cuiping YANG huiping DU Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China

A definition of non-column volume ratio (NCVR) is brought forward by the authors. It is influenced greatly by the slendernessratio of the cylindrical billet and the slope of the wedge on the tool of skew rolling. Using the numerical simulation, the lawof variation in NCVR during the forming process is found out. At the same time experiments have been carried out underdifferent conditions, the result of which are found to be in good agreement with the theoretical predictions.

关键词： Skew rolling, FEM, Non-column volume

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毛叶悬钩子和云南悬钩子叶绿体基因组比较分析

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生物技术进展 2024年第2期14卷 237-247页

作者：胡康于丽平谷薇贺志敏张峻鑫刘子璇黄体冉杨明峰北京农学院生物与资源环境学院北京102206 北京农学院农业农村部华北都市农业重点实验室北京102206 中国科学院大学生命科学学院北京100049

毛叶悬钩子(Rubus poliophyllus)和云南悬钩子(Rubus yunanicus)隶属于蔷薇科(Rosaceae)悬钩子属(Rubus)的尖叶亚组(***),二者的形态特征和地理分布较为相似,因此难以分辨。通过Illumina高通量测序技术得到了二者的叶绿体基因组序列,并... 详细信息

毛叶悬钩子(Rubus poliophyllus)和云南悬钩子(Rubus yunanicus)隶属于蔷薇科(Rosaceae)悬钩子属(Rubus)的尖叶亚组(***),二者的形态特征和地理分布较为相似,因此难以分辨。通过Illumina高通量测序技术得到了二者的叶绿体基因组序列,并对序列进行过滤、组装、注释和分析,构建了基于叶绿体基因组序列的系统发育树。结果表明,毛叶悬钩子和云南悬钩子的基因组全长分别为156298 bp和156299 bp,基因组序列总GC含量均为37.2%。均检测到159个叶绿体基因,其中蛋白质编码基因104个,tRNA基因45个,rRNA基因10个。毛叶悬钩子和云南悬钩子均含有17个回文重复序列,正向重复序列个数分别为19、17,反向重复序列分别为4、3。二者的同义密码子使用度(relative synonymous codon usage,RSCU)>1.00的密码子均有32个,密码子偏好以A/U结尾,有效密码子数均大于45。根据叶绿体全基因组及筛选到的rpoC1-rpoB基因序列所构建的系统发育树显示,毛叶悬钩子和云南悬钩子均聚为同一个分支,表明二者具有较近的亲缘关系。研究结果可为毛叶悬钩子和云南悬钩子的物种分子鉴定、遗传多样性研究及其系统发育关系提供理论依据。

关键词：毛叶悬钩子云南悬钩子叶绿体基因组密码子偏好性系统发育

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