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Nitrate Leaching in an Irrigated Wheat-Maize Rotation Field in the North China Plain

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Pedosphere 2005年第2期15卷 196-203页

作者： zhangyu-ming HUChun-Sheng ZHANGJia-Bao CHENDe-Li LIXiao-Xin InstituteofGeneticandDevelopmentalBiology ChineseAcademyofSciencesShijiazhuang050021（China） InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China） DepartmentofResourceManagementandHorticulture InstituteofLandandFoodResourcetheUniversityofMelbourneParkville3052Victoria（Australia）

Soil water deep drainage and nitrate (NO-3) leaching losses below the root zone were investigated in a 1 ha wheat-maize rotation field under traditional agricultural management that local farmers generally follow in the North China Plain, using the soil water balance method and NO3-N concentration in suction samples. Water drainage, and NO3-N distribution and leaching losses exhibited pronounced spatial and temporal variability. Soil water deep drainage and NO3-N leaching loss mostly occurred during the sum…

关键词： deep drainage nitrate leaching soil water

Ammonia Volatilization and Deriitrification Losses from an Irrigated Maize-Wheat Rotation Field in the North China Plain

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Pedosphere 2004年第4期14卷 533-540页

作者： zhangyu-ming CHENDe-Li ZHANGJia-Bao R.EDIS HUChun-Sheng ZHUAn-Ning InstituteofGeneticsandDevelopmentalBiology ChineseAcademyofSciencesShijiazhuang050021（China） DepartmentofResourceManagementandHorticulture InstituteofLandandFoodResourcetheUniversityofMel-bourneParkville3052Victoria（Australia） InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China）

Ammonia (NH3) volatilization, denitrification loss, and nitrous oxide (N2O) emission were investigated from an irrigated wheat-maize rotation field on the North China Plain, and the magnitude of gaseous N loss from denitrification and NH3 volatilization was assessed. The micrometeorological gradient diffusion method in conjunction with a Bowen Ratio system was utilized to measure actual NH3 fluxes over a large area, while the acetylene inhibition technique (intact soil cores) was employed for measurement of denitrification losses and N2O emissions. Ammonia volatilization loss was 26.62% of the applied fertilizer nitrogen (N) under maize, while 0.90% and 15.55% were lost from the wheat field at sowing and topdressing, respectively. The differences in NH3 volatilization between different measurement events may be due to differences between the fertilization methods, and to differences in climatic conditions such as soil *** losses in the fertilized plots were 0.67%-2.87% and 0.31%-0.49% of the applied fertilizer N under maize and wheat after subtracting those of the controls, respectively. Nitrous oxide emissions in the fertilized plots were approximately 0.08%-0.41% and 0.26%-0.34% of the applied fertilizer N over the maize and wheat seasons after subtracting those of the controls, correspondingly. The fertilizer N losses due to NH3 volatilization were markedly higher than those through denitrification and nitrous oxide emissions. These results indicated that NH3 volatilization was an important N transformation in the crop-soil system and was likely to be the major cause of low efficiencies with N fertilizer in the study area. Denitrification was not a very important pathway of N fertilizer loss, but did result in important evolution of the greenhouse gas N2O and the effect of N2O emitted from agricultural fields on environment should not be overlooked.

关键词： ammonia volatilization denitrification gaseous N loss N_2O emission

Trapping effect modeling for SiC power MESFETs

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Chinese Physics B 2003年第4期12卷 456-456页

作者： YangLin-An ZhangYi-Men YuChun-Li zhangyu-ming MicroelectronicsInstitute XidianUniversityXi'an710071China

Biological removal of methanol from process condensate for the purpose of reclamation

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Journal of Environmental Sciences 2004年第3期16卷 384-386页

作者： WANGYan-ming YANGMin zhangyu GAOMeng-chun ZHANGJing ResearchCenterforEeo-EnvironmentalSciences ChineseAcademyofSciencesBeijing100085China

The biological removal of methanol from condensate of ammonia manufacturing processes for the purpose of reclamation using contact type reactor was studied. Methanol of 60 mg/L was removed completely under an HRT of 1 12 h. Optimal inorganic nutrient dose was determined on evaluating methanol removal performance and dehydrogenase activities(DHA) under different nutrition doses. The optimal inorganic nutrient dose only gave an increase of conductivity of ca. 10 μs/cm 2 in the effluent on treating synthetic condensate containing methanol of 30 mg/L. The results demonstrated that biological removal of methanol was effective for the purpose of recovering the methanol bearing condensate.

关键词： reclamation condensate methanol removal biological contact reactor

UPLC法同时测定不同产地淡竹叶中荭草苷和异荭草苷含量

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亚太传统医药 2024年第10期20卷 31-35页

作者：丁苗陈红林露胡辉贺立豪明章玉劲牌持正堂药业有限公司湖北黄石435100 湖北省中药配方颗粒工程技术研究中心湖北黄石435100 中药保健食品质量与安全湖北省重点实验室湖北大冶435100

目的:建立同时测定淡竹叶中荭草苷和异荭草苷含量的UPLC法,并采用该方法检测不同产地淡竹叶药材中荭草苷和异荭草苷含量。方法:淡竹叶经70%甲醇超声处理后采用Waters CORTECS T3色谱柱(2.1 mm×150 mm, 1.6μm),乙腈-0.2%磷酸溶液为流动... 详细信息

目的:建立同时测定淡竹叶中荭草苷和异荭草苷含量的UPLC法,并采用该方法检测不同产地淡竹叶药材中荭草苷和异荭草苷含量。方法:淡竹叶经70%甲醇超声处理后采用Waters CORTECS T3色谱柱(2.1 mm×150 mm, 1.6μm),乙腈-0.2%磷酸溶液为流动相,梯度洗脱,流速为0.25 mL/min,柱温为40℃,检测波长为348 nm,分别对专属性、线性关系、重复性、中间精密度、准确性、耐用性等进行考察。结果:荭草苷和异荭草苷分别在选定的范围内线性关系良好(r≥0.999 9),平均加标回收率分别为100.10%、100.63%,RSD值分别为2.21%、2.40%(n=9),15批淡竹叶药材中荭草苷含量范围为0.002 3%~0.277 3%,异荭草苷含量范围为0.007 4%~0.339 6%。结论:所建方法准确稳定、重复性好,可用于淡竹叶原料质量控制,不同采收时间淡竹叶药材中荭草苷和异荭草苷含量差异较大,以四川、贵州产地较准,每年6-7月份采收的药材含量较高。

关键词：淡竹叶荭草苷异荭草苷超高效液相色谱

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang Liu Xiang Li Shen Du ming Gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen Wang Wei ming Longfu Chen Tianliang Song Moxi Yele Hao Zhang Long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng Wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： ming‑Yuan Yu Jing Wu Guang Yin Fan‑Zhen Jiao Zhong‑Zhen Yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

Factors Influencing Runoff P Losses from Farmlands of the Dianchi Lake Watershed in Yunnan, China

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Pedosphere 2004年第2期14卷 259-262页

作者： ZHANGNai-ming YUYang,HONGBo CHENJian-Jun zhangyu-Juan CollegeofResourcesandEnvironmentalScience YunnanAgriculturalUniversityYunnan650201（China）.E-mail：zhangnaiming@sinacorn

Effects of factors such as slope, surface soil textuie, fertilization andcrop cover with different rainfall intensities on phosphorus (P) losses in farmland runoff of theDianchi Lake Watershed in Yunnan Province of China were studied through a rainfall simulation testusing a red soil, one of the most widely distributed soils of the study area. Results showed thatthe runoff concentrations of total phosphorus (TP) and P losses differed with the slope, beinghighest when the slope was 18 deg. At twodifferent rainfall intensities, the runoff TP and P losseshad a similar decreasing trend as the surface soil texture became coarser, therefore applying thegrit would decrease P in runofi from soils of farmland on slopes with heavier textures. With wheatas a crop cover the runoff TP concentrations and P losses were significantly lower than those of thebare soil. This showed that plant cover would greatly decrease P in runoff from the farmland of thestudy area. The TP concentration in runoff from the soil two days after fertilization doubled whencompared with that from the non-fertilized soil, indicating that fertilization could mean a dramaticrise in P runoff if irrigation or heavy rainfall occurred immediately after application and that nofertilization before a rain and no irrigation immediately after fertilization would reduce runoff Ploss from the farmland of the study area.

关键词： non-point source (NPS) pollution phosphorus runoff