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Long-term straw return influenced ammonium ion retention at the soil aggregate scale in an Anthrosol with rice-wheat rotations in China

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Journal of Integrative Agriculture 2022年第2期21卷 521-531页

作者： ZHANG Wen-zhao CHEN Xiao-qin WANG Huo-yan WEI Wen-xue ZHOU jian-min Key Laboratory of Agro-ecological Processes in Subtropical Region and Taoyuan Station of Agro-Ecology Research Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125P.R.China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008P.R.China

Soil aggregates are an important controlling factor for the physico-chemical and biological processes such as ammonium(NH;) retention. Straw return to the field is increasingly recommended to promote soil carbon(C) sequestration and improve crop yields. However, the effects of straw return on NH;retention at soil aggregate level in agricultural soils have seldom been investigated. This study aimed to evaluate the influences of long-term straw return on NH;adsorption and fixation in microaggregates(<0.25 mm) with or without soil organic carbon(SOC) oxidization. Soil samples were collected from plots of three treatments, i.e., no fertilizer(CK), inorganic NPK fertilizers(NPK), and inorganic NPK fertilizers with rice straw return(NPKS), from a 20-year-old field trial with rice-wheat rotations in Taihu Lake Region, China. Soil aggregates were separated using wet-sieving method. The SOC of microaggregates was oxidized by H;O;. The results showed that longterm straw return significantly increased SOC and NH;adsorption, but inhibited NH;fixation in microaggregates. NH;adsorption potential and strength-obtained from adsorption isotherms-increased, but NH;fixation decreased along with increasing SOC in microaggregates, indicating the important role of SOC in NH;adsorption and fixation. This was verified by the SOC oxidization test that showed a relative decrease in NH;adsorption potential for the NPKS treatment and an increase in NH;fixation in all three treatments. Therefore, long-term straw return influences NH;adsorption and fixation by enhancing SOC content and could improve N availability for crop uptake and minimize applied N fertilizer losses in rice-wheat cropping systems.

关键词： soil organic carbon microaggregates NH4+ adsorption fixation

Designed synthesis of chlorine and nitrogen co-doped Ti_(3)C_(2)MXene quantum dots and their outstanding hydroxyl radical scavenging properties

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Journal of Materials Science & Technology 2021年第19期78卷 30-37页

作者： Lin Zhao Zhao Wang yan Li Sen Wang Lifeng Wang Zhaojun Qi Qiang Ge Xiaoguang Liu Jin zhong Zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCalifornia 95064United States

As a novel zero-dimensional(0D)material,metal carbides and/or carbonitrides(MXenes)quantum dots(MQDs)show unique photoluminescence properties and excellent ***,due to the limited synthesis methods and research to date,many new features have yet to be ***,to explore their new properties and expand biological applications,chlorine and nitrogen co-doped Ti_(3)C_(2)MXene quantum dots(Cl,N-Ti_(3)C_(2)MQDs)were designed and synthesized,and their hydroxyl radical scavenging properties were investigated for the first time,revealing outstanding ***,N-Ti_(3)C_(2)MQDs was directly stripped from bulk Ti_(3)Al C_(2)by electrochemical etching,while N and Cl are successfully introduced to carbon skeleton and Ti boundaries in the etching process by electrochemical reactions between selected electrolytes and Ti_(3)C_(2)skeleton,*** obtained Cl,N-Ti_(3)C_(2)MQDs exhibit large surface-to-volume ratio due to small particle size(ca.3.45 nm)and excellent higher scavenging activity(93.3%)and lower usage(12.5μg/m L)towards hydroxyl radicals than the previous reported graphene-based *** underlying mechanism of scavenging activity was also studied based on the reduction experiment with potassium permanganate(KMnO_(4)).The reducing ability of the intrinsic Ti_(3)C_(2)structure and electron donation of double dopants are the main contributors to the outstanding scavenging activity.

关键词： Ti_(3)C_(2)MXene quantum dots Chlorine and nitrogen co-doping Hydroxyl radical Scavenger

Fuzzy Synthetic Evaluation of Wetland Soil Quality Degradation:A Case Study on the Sanjiang Plain,Northeast China

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Pedosphere 2009年第6期19卷 756-764页

作者： WANG jian-Hua LU Xian-Guo jianG Ming LI Xiao-yan TIAN Jing-Han State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 (China) Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 (China) Hebei Cangzhou Teachers College Cangzhou 061001 (China) College of Resources Science and Technology Beijing NoT-real University Beijing 100875 (China)

Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursuit evaluation (PPE) model based on real-coded accelerating genetic algorithm were introduced to evaluate quality variations in top layers of the main wetland soils on the Sanjiang Plain in 1999 and 2003, respectively. As soil quality degradation boundaries were vague, this study established two fuzzy synthetic evaluation (FSE) models based on the original data and criteria used in the RSQE and PPE models. The outputs of the two FSE models were obtained by choosing two fuzzy composite operators M(∧, ∨) and M(·, ⊕). Statistical analysis showed that the results of the FSE, RSQE, and PPE models were correlated. In particular, outputs of the FSE model using M(·, ⊕) were significantly correlated with those of the RSQE model with r = 0.989 at P jiang Plain was of scientific and practical significance for protection and management of soils and for sustainable development of agriculture in this area in the future.

关键词： fuzzy composite operator model soil protection and management sustainable development of agriculture

不同谷子品种富硒能力及外源硒协同增效作用的研究

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中国土壤与肥料 2024年第4期 206-213页

作者：黄子鹏魏丹迟凤琴姚磊丁建莉李艳金梁何义利李沛东北农业大学资源与环境学院黑龙江哈尔滨150030 北京市农林科学院植物营养与资源环境研究所北京100097 黑龙江省黑土保护利用研究院黑龙江哈尔滨150086 北京市农林科学院农业生物技术研究所北京100097

为了实现缺硒带谷子高效富硒生产的目标,研究京郊谷子在缺硒土壤(褐土,硒含量0.266 mg/kg)吸收土壤硒的能力和喷施外源硒及增效制剂对硒的吸收效率。以“京谷2号”“京谷3号”“京谷4号”谷子为试验材料,设置4个硒水平(0、11.25、15.00... 详细信息

为了实现缺硒带谷子高效富硒生产的目标,研究京郊谷子在缺硒土壤(褐土,硒含量0.266 mg/kg)吸收土壤硒的能力和喷施外源硒及增效制剂对硒的吸收效率。以“京谷2号”“京谷3号”“京谷4号”谷子为试验材料,设置4个硒水平(0、11.25、15.00、22.50 g/hm^(2))和2个增效剂(18.75 L/hm^(2)腐植酸和0.19 L/hm^(2)有机硅),采用田间随机区组试验,研究施用外源硒(Na_(2)SeO_(3))条件下,谷子品种与富硒的交互作用和增效制剂对富硒能力的提升。通过测定谷子籽粒硒含量、籽粒硒利用效率和强化指数,比较不同增效剂与硒协同作用对谷子富硒能力提升效率的影响,为生产中优化高附加值富硒农产品生产提供参考。结果表明:CK处理中,“京谷2号”籽粒硒含量、籽粒硒生物富集指数最高,筛选“京谷2号”为土壤硒富集能力强品种,Se处理中,“京谷4号”籽粒硒含量、硒利用效率、强化指数均最高,筛选“京谷4号”为外源硒富集能力强品种;腐植酸和有机硅增效剂与硒协同作用比较,喷施腐植酸增效剂显著提高谷子籽粒硒含量、硒利用效率和强化指数,其提高谷子富硒效率效果明显;喷施腐植酸增效剂条件下,“京谷4号”籽粒硒含量比Se2处理增加30.37%,“京谷2号”“京谷3号”籽粒硒含量比Se3处理增加41.50%、16.81%。缺硒土壤生产富硒谷子,品种选择“京谷4号”,选择腐植酸增效剂及15.00 g/hm^(2)Na_(2)SeO_(3),其中“京谷2号”“京谷3号”,喷施腐植酸增效剂可减少1/3亚硒酸钠用量,达到增加籽粒硒含量的目的。

关键词：谷子叶面施硒增效剂籽粒硒含量籽粒品质

饲粮中添加三七渣对西畴乌骨鸡生长性能、血清生化指标及肉品质的影响

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饲料研究 2024年第13期47卷 47-52页

作者：胡耀李凡梁永兴盘道兴朱德颜黄兴粉王献钟正阳文山州农业科学院云南文山663099 西畴县农业农村和科学技术局云南文山663599

试验旨在研究在饲粮中添加三七渣对西畴乌骨鸡生长性能、血清生化指标及肉品质的影响。将270只体重相近、28日龄的西畴乌骨鸡分为3组,每组5个重复,每个重复18只西畴乌骨鸡,公、母各半。对照组饲喂基础饲粮,试验Ⅰ组、Ⅱ组分别在基础饲... 详细信息

试验旨在研究在饲粮中添加三七渣对西畴乌骨鸡生长性能、血清生化指标及肉品质的影响。将270只体重相近、28日龄的西畴乌骨鸡分为3组,每组5个重复,每个重复18只西畴乌骨鸡,公、母各半。对照组饲喂基础饲粮,试验Ⅰ组、Ⅱ组分别在基础饲粮中添加4%和8%的三七渣。预试期7 d,正式试验期为60 d。结果显示:与对照组相比,试验Ⅱ组料重比显著降低(P<0.05),肌肉氨基酸总量显著提高(P<0.05);试验Ⅰ组、Ⅱ组平均日采食量、血清甘油三酯、肌肉粗脂肪和饱和脂肪酸含量均显著降低(P<0.05),试验Ⅰ组、Ⅱ组肌肉水分、不饱和脂肪酸、必需脂肪酸含量显著提高(P<0.05)。研究表明,饲粮中添加三七渣可以提高西畴乌骨鸡生长性能,改善血清生化指标和肉品质,西畴乌骨鸡生产中添加4%的三七渣较为适宜。

关键词：三七渣西畴乌骨鸡生长性能血清生化指标营养成分氨基酸脂肪酸

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Spatio-temporal Characteristics of Area Coverage and Observation Geometry of the MISR Land-surface BRF Product: A Case Study of the Central Part of Northeast Asia

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Chinese Geographical Science 2019年第4期29卷 679-688页

作者： LI jian CHEN Shengbo QIN Wenhan Mike MUREFU WANG Yufei YU yan ZHEN Zhijun College of Geo-Exploration Science and Technology Jilin UniversityChangchun 130026 China Climate Centre of Jilin Province Changchun 130062 China

The Multi-angle imaging spectroradiometer(MISR) land-surface(LS) bidirectional reflectance factor(BRF) product(MILS_BRF) has unique semi-simultaneous multi-angle sampling and global coverage. However, unlike on-satellite observations, the spatio-temporal characteristics of MILS_BRF data have rarely been explicitly and comprehensively analysed. Results from 5-yr(2011–2015) of MILS_BRF dataset from a typical region in central Northeast Asia as the study area showed that the monthly area coverage as well as MILS_BRF data quantity varies significantly, from the highest in October(99.05%) through median in June/July(78.09%/75.21%) to lowest in January(18.97%), and a large data-vacant area exists in the study area during four consecutive winter months(December through March). The data-vacant area is mainly composed of crop lands and cropland/natural vegetation mosaic. The amount of data within the principal plane(PP)±30°(nPP) or cross PP ±30°(nCP), varies intra-annually with significant differences from different view zeniths or forward/backward scattering directions. For example, multiple off-nadir cameras have nPP but no nCP data for up to six months(September through February), with the opposite occurring in June and July. This study provides explicit and comprehensive information about the spatio-temporal characteristics of product coverage and observation geometry of MILS_BRF in the study area. Results provide required user reference information for MILS_BRF to evaluate performance of BRDF models or to compare with other satellite-derived BRF or albedo products. Comparing this final product to on-satellite observations, what was found here reveals a new perspective on product spatial coverage and observation geometry for multi-angle remote sensing.

关键词： multi-angle remote sensing Multi-angle Imaging Spectroradiometer (MISR) bidirectional reflectance factor (BRF) spatio-temporal characteristics observation geometry

Flexible and wearable BaTiO_(3)/polyacrylonitrile-based piezoelectric sensor for human posture monitoring

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Science China(Technological Sciences) 2022年第4期65卷 858-869页

作者： MU JiLiang XIAN Shuai YU JunBin LI Zhengyang ZHAO JuanHong zhong JiXin HAN XiaoTao HOU XiaoJuan HE jian CHOU Xiujian Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan 030051China

Tactile sensors are essential components of wearable electronic devices,but there are still various problems in terms of energy supply,flexibility and skin *** this paper,we report a self-powered flexible tactile sensor(FTS)mainly composed of a BaTiO_(3)/polyacrylonitrile/Ecoflex(BTO/PAN/Ecoflex)composite film,which can be used for dynamically monitoring human plantar pressure,posture and other physiological and motion *** the synergistic piezoelectric properties of PAN and BTO,the output voltage/current of the BTO/PAN/Ecoflex composite film is 4.5/5.8 times that of the BTO/Ecoflex composite film,with maximum instantaneous power that can reach up to 3.375μ*** the action of external pressure stress,the FTS can reach a normalized voltage sensitivity and voltage linearity of 0.54 V/N and 0.98,***,a human-machine interaction test system is built,which can display the stress changes of human body monitoring parts in real time according to voltage changes and different color *** developed human-machine interaction test system provides a new idea for the diagnosis of flatfoot and other medical ***,this work proposes new FTSs that use a BTO/PAN/Ecoflex composite film with high sensitivity and great output performance,thus exhibiting immense potential application prospects in medical research,personalized recognition and human-machine interaction.

关键词： PAN synergistic piezoelectricity composite film flexible and wearable human posture monitoring

Laser stripping of Ag shell from Au@Ag nanoparticles

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Rare Metals 2021年第12期40卷 3454-3459页

作者： De-Zhi Zhu jian-Feng yan Zhen-Wei Liang Jia-Wang Xie Hai-Lin Bai Key Laboratory for Advanced Materials Processing Technology Ministry of Education of ChinaState Key Laboratory of TribologyDepartment of Mechanical EngineeringTsinghua UniversityBeijing 100084China

Metallic nanoparticles(NPs)are a class of important materials with widespread applications due to their chemical stability and high photothermal conversion *** is essential to post-control the morphology and structure of metallic NPs for practical *** processing of metallic NPs has been widely *** of previous studies on the reshaping process have been related to the single metallic NPs,and no attempt has been made to separate the components in bimetallic ***,the stripping of Ag shell from Au@Ag NPs based on ultrafast laser excitation was *** experimental work combined spectrum and microscopy analysis showed the structure transformation of Au@Ag *** the electric field simulation,the stripping of the Ag shell may arise from the electric field effect.

关键词： red image Laser stripping of Ag shell from Au@Ag nanoparticles

Lentivirus-mediated shRNA interference targeting STAT3 inhibits human pancreatic cancer cell invasion

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World Journal of Gastroenterology 2009年第30期15卷 3757-3766页

作者： Guang yan Chen Huang Jun Cao Ke-jian Huang Tao jiang Zheng-Jun Qiu Department of General Surgery Affiliated First People's Hospital Shanghai Jiao Tong University Shanghai 200080 China

AIM： To investigate RNA interference targeting signal transducer and activator of transcription-3 （STAT3） on invasion of human pancreatic cancer cells.METHODS： We constructed three plasmids of RNA interference targeting the STAT3 gene. After LV （lentivirus）-STAT3siRNA （STAT3 small interfering RNA） the vector was transfected into the human pancreatic cell line, SW1990 and cell proliferation was measured by the MTT assay. Flow cytometry was used to assess cell cycle. Vascular endothelial growth favor （VEGF） and matrix metalloproteinase-2 （MMP-2） mRNA and protein expression were examined by quantitative PCR and western blotting, respectively. The invasion ability of SW1990 cells was determined by cell invasion assay.RESULTS： We successfully constructed the LVSTAT3siRNA lentivirus vector and proved that it can suppress expression of STAT3 gene in SW1990 cells. RNA interference of STAT3 by the LV-STAT3siRNA construct significantly inhibited the growth of SW1990 cells, in addition to significantly decreasing both VEGF and MMP-2 mRNA and protein expression. Moreover, suppression of STAT3 by LV-STAT3siRNA decreased the invasion ability of SW1990 cells.CONCLUSION： The STAT3 signaling pathway may provide a novel therapeutic target for the treatment of pancreatic cancer since it inhibits the invasion ability of pancreatic cancer cells.

关键词： Signal transducer and activator of transcription3 RNA interference Lentivirus vector Pancreatic cancercells Invasion