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氮肥用量对玉米-油菜和水稻-油菜轮作模式下油菜产量及氮素吸收利用的影响

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作物学报 2024年第8期50卷 2067-2077页

作者：刘陈王昆昆廖世鹏杨佳群丛日环任涛李小坤鲁剑巍华中农业大学资源与环境学院/农业农村部长江中下游耕地保育重点实验室/华中农业大学微量元素研究中心湖北武汉430070

旱-旱和水-旱轮作是我国长江流域冬油菜的典型种植模式,氮养分缺乏是油菜产量主要限制因子。利用2016—2023年在湖北省武汉市布置的裂区同田对比定位试验,探究氮肥用量对不同轮作模式下油菜产量和氮素吸收利用的影响差异,为科学施氮提... 详细信息

旱-旱和水-旱轮作是我国长江流域冬油菜的典型种植模式,氮养分缺乏是油菜产量主要限制因子。利用2016—2023年在湖北省武汉市布置的裂区同田对比定位试验,探究氮肥用量对不同轮作模式下油菜产量和氮素吸收利用的影响差异,为科学施氮提供依据。试验设计的主处理为旱地油菜(玉米-油菜)和水田油菜(水稻-油菜)2种轮作模式,副处理为4个氮肥用量(0 kg N hm^(-2)、75 kg N hm^(-2)、150 kg N hm^(-2)、225 kg N hm^(-2)),分析了油菜产量、产量构成因子和氮素积累量等相关指标。7年试验结果表明,旱地和水田油菜的产量和氮素吸收在不同氮肥投入下的响应存在差异。当不施氮或低施氮(75 kg N hm^(-2))时,水田油菜产量显著高于旱地油菜,分别高出53.9%和20.8%,地上部氮素积累量分别高出57.8%和18.3%;当施氮量为150 kg N hm^(-2)时,2种轮作无显著差异;在高施氮(225 kg N hm^(-2))时,旱地油菜产量和氮素积累量较水田分别增加11.2%和16.0%。旱地油菜的氮肥农学利用效率、贡献率和表观利用率较水田油菜分别平均增加16.5%、20.5%和22.0%,氮肥对旱地油菜的增产潜力更大,但水田油菜季土壤基础氮素供应量较旱地高61.5%,对氮肥的依赖性更小。综上,增加氮肥用量显著提高了油菜产量和氮素积累,水田油菜在低氮投入下表现出较高的稳产性,而旱地油菜在较高氮投入下丰产潜力更高。因此,在实际生产中应根据不同轮作模式调整油菜施氮量,旱地油菜可以适当增加氮肥用量以获得高产,水田油菜要充分利用土壤供氮能力适当控制氮肥用量,以达到油菜高产高效生产和氮肥高效利用的目的。

关键词：玉米-油菜轮作水稻-油菜轮作氮肥用量油菜产量氮素积累量

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滇东南薄竹山花岗岩年代学、地球化学特征及地质意义

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矿物岩石地球化学通报 2024年第3期43卷 621-635页

作者：黄建国任涛刘红卫罗光明管申进昆明理工大学国土资源工程学院昆明650093 云南省国土资源规划设计研究院昆明650216

滇东南薄竹山地区W-Sn-Pb-Zn多金属矿床与该区大型复式花岗岩体有密切的成因联系。为了探讨该花岗岩体的侵位时代、岩石成因及形成背景,对薄竹山花岗岩开展了岩石地球化学、锆石U-Pb定年及Hf同位素测试。结果表明,该花岗岩可划分为两期... 详细信息

滇东南薄竹山地区W-Sn-Pb-Zn多金属矿床与该区大型复式花岗岩体有密切的成因联系。为了探讨该花岗岩体的侵位时代、岩石成因及形成背景,对薄竹山花岗岩开展了岩石地球化学、锆石U-Pb定年及Hf同位素测试。结果表明,该花岗岩可划分为两期,其中晚期花岗岩LA-ICP-MS锆石U-Pb年龄为(87.08±0.55)~(87.29±0.69)Ma。两期花岗岩均具高的SiO_(2)(63.37%~72.07%)、K_(2)O(4.96%~6.19%),贫Fe、Mg的特征,A/CNK值为1.03~2.42,轻重稀土元素分异明显(LREE/HREE=14.0~26.5),Eu明显负异常(δEu=0.38~0.62),富含大离子亲石元素Rb、Th、U及稀土元素La、Ce、Nd,亏损Ba、Ta、Nb、Sr、Y和Yb,ε_(Hf)(t)值为−9.31~−5.14,具有高钾钙碱性过铝质S型花岗岩的地球化学和同位素特征;Hf同位素二阶段模式年龄(t_(DM2))为1476~1737 Ma,说明岩浆可能来源于早中元古代下地壳部分熔融。综合研究认为,薄竹山花岗岩是白垩纪伸展背景下软流圈地幔上涌导致的早中元古代下地壳物质部分熔融所形成。

关键词：锆石U-Pb定年地球化学 S型花岗岩薄竹山滇东南

A Proposed Batch In vitro Apparatus for Conducting Rumen FermentationExperiment

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Agricultural Sciences in China 2008年第7期7卷 887-894页

作者： ZHANG Guang-qin ren Hong-tao College of Animal Science Henan University of Science and Technology Luoyang 471003 P.R. China

This research proposes a batch in vitro rumen apparatus modified from Daisy incubator and procedures of measuring feed digestion by using nylon bag to replace the traditional centrifuging and filtration methods, for the purpose of studying ruminal fermentation. The apparatus consists of 8 sets of airtight reaction vessels which rotated at a speed of 1 r/min and located inside a thermostatic cabin. Optimum procedures was proved to be that the volume of incubation fluid was 400 mL; fineness and size of test feed were 0.125-0.25 mm and 0.4 g, respectively; amount of bags in one vessel was 6; fermentation diet in a single incubation was 4-5 g. Comparing experiments showed that fermentation speed attained with the apparatus was about 15-20% greater than that attained with flask-shaking machine method （revolutionary speed is 100 r/min） and more accurate results could be obtained with the new apparatus. In conclusion, this apparatus could provide an efficient mixing action, and the procedure could allow sensitive detection of differences in ruminal fermentation in a time-saving way.

关键词： in vitro apparatus ruminal fermentation nylon bag

Nutrient Efficiency of Winter Oilseed Rape in an Intensive Cropping System： A Regional Analysis

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Pedosphere 2017年第2期27卷 364-370页

作者： LI Hui LU Jianwei ren tao LI Xiaokun CONG Rihuan College of Resources and Environment Huazhong Agricultural University Wuhan 430070 (China) Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River) Ministry of Agriculture Wuhan 430070 (China)

Fertilization is essential for oilseed rape because it is sensitivity to nutrient deficiency, especially for winter oilseed rape(Brassica napus L.). To investigate regional nutrient efficiency and nutrient uptake-yield relationship of winter oilseed rape in an intensive cropping system, this study used data from 619 site-year on-farm experiments carried out in the winter oilseed rape planting area of the Yangtze River Basin, China from 2005 to 2010, with large yield in the range of 179–4 470 kg ha^(-1). Currently recommended application rates of N, P and K fertilizers increased rapeseed yield at different levels of soil indigenous nutrient supply(INS) in this region. Boundary values of plant nutrient uptake were established to analyze the nutrient uptake-yield relationship of winter oilseed rape(internal nutrient efficiency), i.e., 128 kg N ha^(-1), 24 kg P ha^(-1), and 122 kg K ha^(-1). The internal nutrient efficiency declined by 48.2%–64.1% when nutrient uptake exceeded the boundary value, resulting in excessive nutrient uptake(i.e., low yield response with high nutrient uptake), especially for K. In the intensive cropping system, agronomic efficiencies of N, P, and K were 5.9, 3.4, and3.6 kg kg^(-1), and recovery efficiencies of N, P, and K were 35.6%, 24.1%, and 36.8%, respectively. These findings showed that the fertilization rate should be optimized by considering INS, nutrient status, and nutrient efficiency of winter oilseed rape. In this study,considering the lower yield improvement to high K uptake levels and low K fertilizer efficiency, application rate of K fertilizer should be reduced since soil K deficiency has already been mitigated.

关键词： agnomic efficiency fertilization indigenous nutrient supply internal nutrient efficiency nutrient uptake recoveryefficiency regional scale yield

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激光熔覆Ni基涂层组织性能研究

山西冶金 2024年第2期47卷 1-4页

作者：任涛王琦张清华姜威山西工程技术学院材料科学与工程系山西阳泉045000

以17-4PH沉淀硬化马氏体不锈钢叶片的激光再制造修复技术为背景,选取镍铬合金与WC-Co复合粉末作为熔覆材料,采用激光熔覆技术在17-4PH不锈钢表面制备复合涂层,通过调整激光功率和送粉速度两个工艺参数进行实验。通过观察试样熔覆层的微... 详细信息

以17-4PH沉淀硬化马氏体不锈钢叶片的激光再制造修复技术为背景,选取镍铬合金与WC-Co复合粉末作为熔覆材料,采用激光熔覆技术在17-4PH不锈钢表面制备复合涂层,通过调整激光功率和送粉速度两个工艺参数进行实验。通过观察试样熔覆层的微观组织,并对熔覆层的力学性能进行测试,结果表明:当激光功率为1700 W时,涂层的组织均匀致密。涂层的硬度和摩擦磨损性能均高于基体。最优的工艺参数激光功率为1700 W,送粉速度为30 mg/s,此工艺参数下制备的复合涂层可以有效提高17-4PH不锈钢的硬度和耐摩擦磨损性。

关键词：激光熔覆 Ni基复合涂层工艺参数组织性能

Experimental Study on Working Performance of Rice Rope Direct Seeding Machine

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Agricultural Sciences in China 2010年第2期9卷 275-279页

作者： LU Xiao-rong LU Xiao-lian ren Wen-tao College of Information & Engineering Sichuan Agricultural University Ya'an 625014 P.R.China Department of Electronics & Information Chuzhou College Chuzhou 239000 P.R.China College of Engineering Shenyang Agricultural University Shenyang 110161 P.R.China

Structure and sowing principles of rice rope direct seeding machine are introduced. In order to test the machine＇ s working performance, such as compacting effect, sowing depth, influence of sowing device to rice rope, etc., field experiments were conducted. It is concluded that mean slip ratio of compacting wheel 1 is 4.44%, wheel 2 is 5.58%, wheel 3 is 7.81%, and wheel 4 is 6.96%; mean depth of planting is 29.72 mm, and mean variability coefficient of planting depth is 6.39%. Maximum variability coefficient of planting depth is 8.40%. Rice rope＇s snapping is closely related with the machine＇s speed and guide thread wheel by sowing device orthogonal experiments. Test results show that the machine has a rational design, safe work and meets to the requirements of planting. This study has laid the foundation for further studying the project.

关键词： rice rope direct seeding machine slip ratio planting depth sowing device experiments

An overview and recent advances in electrocatalysts for direct seawater splitting

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1408-1426页

作者： Hao-Yu Wang Chen-Chen Weng Jin-tao ren Zhong-Yong Yuan Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin300350China

In comparison to pure water,seawater is widely accepted as an unlimited *** direct seawater splitting is economical and eco-friendly,but the key challenges in seawater,especially the chlorine-related competing reactions at the anode,seriously hamper its practical *** development of earth-abundant electrocatalysts toward direct seawater splitting has emerged as a promising *** efficient electrocatalysts with improved selectivity and stability are of significance in preventing the interference of side reactions and resisting various *** review first discusses the macroscopic understanding of direct seawater electrolysis and then focuses on the strategies for rational design of electrocatalysts toward direct seawater *** perspectives of improved electrocatalysts to solve emerging challenges and further development of direct seawater splitting are also provided.

关键词： seawater splitting electrocatalysts oxygen evolution reaction hydrogen evolution reaction chlorine chemistry

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中枢神经系统曲霉菌病

中国现代神经疾病杂志 2024年第4期24卷 258-264页

作者：倪品菲范思远李佳有慧赵大春任海涛关鸿志中国医学科学院北京协和医学院北京协和医院神经科100730 中国医学科学院北京协和医学院北京协和医院放射科100730 中国医学科学院北京协和医学院北京协和医院病理科100730

研究背景中枢神经系统曲霉菌感染临床罕见,本文报道1例经病理确诊的中枢神经系统曲霉菌病患者,分析其临床特点并复习文献,总结诊断与治疗要点。方法与结果女性患者,50岁,临床主要表现为进行性四肢无力、癫痫发作、认知功能下降、性格改... 详细信息

研究背景中枢神经系统曲霉菌感染临床罕见,本文报道1例经病理确诊的中枢神经系统曲霉菌病患者,分析其临床特点并复习文献,总结诊断与治疗要点。方法与结果女性患者,50岁,临床主要表现为进行性四肢无力、癫痫发作、认知功能下降、性格改变,系统性炎症及免疫学指标未见明显异常,脑脊液常规、生化、细胞学、病原学检测未见明显异常;头部MRI显示双侧额顶叶异常信号伴片状、环形强化,脑膜强化;脑组织活检提示血管炎及脑组织坏死伴出血,六胺银染色可见有分隔的真菌菌丝,分叉呈45°;最终确诊为中枢神经系统曲霉菌病,经抗真菌治疗后症状好转,复查MRI病灶较前缩小。结论中枢神经系统曲霉菌病可发生于免疫功能正常人群,临床表现缺乏特异性,脑脊液可无炎症改变,宏基因组学第二代测序可呈阴性,脑组织活检术是诊断的“金标准”,早期、足量、足疗程予以伏立康唑抗真菌治疗可以改善预后。

关键词：曲霉菌病中枢神经系统真菌感染伏立康唑活组织检查病理学

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专用肥用量对油菜籽产量及品质的影响

中国油料作物学报 2024年第2期46卷 359-369页

作者：方雯任涛刘方舟蒋博鲁明星张哲鲁剑巍华中农业大学资源与环境学院/农业农村部长江中下游耕地保育重点实验室/华中农业大学微量元素研究中心湖北武汉430070 湖北省油菜办公室湖北武汉430070 全国农业技术推广服务中心北京100125

肥料是保障农作物生长的重要物质基础,油菜专用配方肥施用作为油菜轻简化种植的关键技术在生产中广泛应用,明确兼顾丰产和优质双重目标的油菜专用配方肥适宜用量将为油菜绿色高质生产提供关键技术支撑。通过2020-2021年在湖北省江陵县... 详细信息

肥料是保障农作物生长的重要物质基础,油菜专用配方肥施用作为油菜轻简化种植的关键技术在生产中广泛应用,明确兼顾丰产和优质双重目标的油菜专用配方肥适宜用量将为油菜绿色高质生产提供关键技术支撑。通过2020-2021年在湖北省江陵县、沙洋县及洪湖市等3个地点的田间试验,设置了0、450、600、750和900 kg/hm^(2)5个肥料用量,研究不同专用配方肥用量对油菜产量、产量构成因子、养分含量及品质的影响。施用专用配方肥可显著提高单株角果数、每角粒数及千粒重,进而提升油菜籽产量。与不施肥处理相比,专用配方肥施用量为900kg/hm^(2)时,单株角果数、每角粒数及千粒重平均值分别增加277.4%、17.9%和9.2%,油菜籽增产率达300%。油菜专用配方肥的施用显著影响了油菜籽油分及蛋白质含量,与不施肥处理相比,油菜籽蛋白质含量在专用配方肥用量为900 kg/hm^(2)时最高,增长率为16.0%~34.6%,而含油量最低,相较于不施肥降低了4.4%~11.6%。相关性分析表明,增施专用肥显著增加了油菜籽产量、含水率、蛋白质、芥酸及脂肪酸组成,减少了油菜籽硫甙含量。兼顾产量、油菜籽品质和饲用等方面,专用肥用量控制在750~900 kg/hm^(2)时,能够在获得较高的菜籽产量及蛋白质产量的同时,菜籽中硫甙、芥酸及饱和脂肪酸的生成增幅较小并提高了产油量。要在油菜增产的基础上继续追求品质提升,可结合不同地力条件,适量增加中微量元素,以进一步提高油菜籽含油率和改善脂肪酸的组成,实现产量与品质的协同。

关键词：油菜专用肥适宜用量产量品质相关性分析