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北方地区土壤速效养分及容重对秸秆还田的响应

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中国农学通报 2023年第5期39卷 100-108页

作者：孙力扬徐明岗王晋峰李建华刘平孙楠山西农业大学资源环境学院山西太谷030800 山西农业大学生态环境产业技术研究院/土壤环境与养分资源山西省重点实验室太原030031 中国农业科学院农业资源与农业区划研究所/农业农村部耕地质量监测与评价重点实验室北京100081

本研究旨在探明中国北方地区土壤速效养分及容重对秸秆还田的响应,选择秸秆还田为主要研究目标,通过设置“秸秆还田”、“理化性质”、“华北”、“东北”、“西北”等关键词在中国知网、万方等多个数据库中,筛选出60篇关于秸秆还田对... 详细信息

本研究旨在探明中国北方地区土壤速效养分及容重对秸秆还田的响应,选择秸秆还田为主要研究目标,通过设置“秸秆还田”、“理化性质”、“华北”、“东北”、“西北”等关键词在中国知网、万方等多个数据库中,筛选出60篇关于秸秆还田对作物产量和土壤改良影响效应和影响因素的文献。采用Meta分析法定量研究土壤速效养分和容重对秸秆还田的响应。结果表明:秸秆还田能够显著(P15000 kg/hm^(2))则显著(P<0.05)降低了土壤容重;免耕相比旋耕、深耕、浅耕可以显著(P<0.05)提升土壤有机碳、碱解氮和速效钾的含量,深耕可显著(P<0.05)降低土壤容重;小麦和玉米秸秆均对土壤容重和速效养分的提升有显著效果,但两种作物秸秆间并无显著差异。北方地区推荐中高量秸秆还田配合免耕措施,不仅能够显著增加土壤养分含量,而且可改善土壤理化性质,从而达到培肥地力的效果。

关键词：秸秆还田速效养分土壤容重中国北方 Meta分析

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真空相变供热系统节能优化

山西冶金 2022年第8期45卷 102-103,144页

作者：赵利平王铁民季淑蕊孙立扬首钢京唐钢铁联合有限责任公司能源与环境部河北唐山063200

随着真空相变技术日渐成熟并应用于采暖系统,彻底杜绝了冲渣水余热回收利用过程中对换热器壁面造成的污染、堵塞、腐蚀现象,且在经济运行、精细化操作方面仍存在很大的优化空间。以尽可能降低对冲渣工艺影响又可以实现最大幅度取热为原... 详细信息

随着真空相变技术日渐成熟并应用于采暖系统,彻底杜绝了冲渣水余热回收利用过程中对换热器壁面造成的污染、堵塞、腐蚀现象,且在经济运行、精细化操作方面仍存在很大的优化空间。以尽可能降低对冲渣工艺影响又可以实现最大幅度取热为原则,详细阐述真空相变直热机在运行过程中出现的问题,并提出相应解决方案,降低能源消耗,节能效果显著,为钢铁企业渣水余热用于供热系统提供了理论支持。

关键词：直热机采暖异常措施效果

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改进建筑60秒

世界建筑 2019年第10期 122-122页

作者：叶扬清华大学无障碍发展研究院

我们仿效BBC的广播节目"60秒改进世界"(Sixty Second Idea to Improve the World)推出了"改进建筑60秒"栏目,每期将在世界范围内采访两位人物,请他们就建筑、城市、景观、技术等相关问题在60秒的时间里讲出一个或两个有启发性、批判性... 详细信息

我们仿效BBC的广播节目"60秒改进世界"(Sixty Second Idea to Improve the World)推出了"改进建筑60秒"栏目,每期将在世界范围内采访两位人物,请他们就建筑、城市、景观、技术等相关问题在60秒的时间里讲出一个或两个有启发性、批判性甚至有争议性的观点。本栏目如实记录了他们的话,采访所拍摄的视频将会出现在我们的相关网页上。所述观点只代表嘉宾本人,与本杂志立场无关。

关键词：建筑广播节目 Idea BBC 启发性批判性世界栏目

固相萃取-高效液相色谱法测定羊奶中四环素和土霉素的残留量

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鞍山师范学院学报 2024年第6期26卷 49-52页

作者：罗维巍孙丽阳徐丽丽刁全平李铁纯鞍山师范学院化学与生命科学学院辽宁鞍山114007 辽宁省天然产物活性分子开发及利用重点实验室辽宁鞍山114007 潍坊生物医药产业园服务中心山东潍坊261000

建立固相萃取-高效液相色谱测定羊奶中四环素和土霉素残留量的方法.样品用0.1 mol·L^(-1)的EDTA-Mcllvaine缓冲液提取、HLB固相萃取柱净化、甲酸-甲醇体系洗脱、HPLC测定其残留量.结果表明:四环素和土霉素在0.1~100μg·mL^(-1)浓度范... 详细信息

建立固相萃取-高效液相色谱测定羊奶中四环素和土霉素残留量的方法.样品用0.1 mol·L^(-1)的EDTA-Mcllvaine缓冲液提取、HLB固相萃取柱净化、甲酸-甲醇体系洗脱、HPLC测定其残留量.结果表明:四环素和土霉素在0.1~100μg·mL^(-1)浓度范围内线性关系良好,检出限分别为0.021μg·mL^(-1)和0.030μg·mL^(-1),加标回收率分别为95.15%~95.94%和89.84%~97.93%.该方法准确、可靠、重复性好,可用于羊奶中四环素和土霉素残留量的测定.

关键词：羊奶四环素土霉素固相萃取高效液相色谱

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榛子壳中棕色素提取工艺研究

鞍山师范学院学报 2017年第4期19卷 46-50页

作者：罗维巍吕琳琳孙丽阳刁全平李铁纯鞍山师范学院化学与生命科学学院辽宁鞍山114007

采用乙醇溶剂浸渍法提取榛子壳棕色素,研究了提取温度、乙醇浓度、料液比、提取时间对提取效果的影响.通过正交实验确定棕色素的最佳提取条件为:提取温度90℃,乙醇浓度50%,料液比1∶22,提取时间100 min.在此最佳条件下,榛子壳中棕色素... 详细信息

采用乙醇溶剂浸渍法提取榛子壳棕色素,研究了提取温度、乙醇浓度、料液比、提取时间对提取效果的影响.通过正交实验确定棕色素的最佳提取条件为:提取温度90℃,乙醇浓度50%,料液比1∶22,提取时间100 min.在此最佳条件下,榛子壳中棕色素的最大提取量为15.85 mg/g.

关键词：榛子壳棕色素提取条件

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甲状腺功能亢进症和甲状腺癌并存10例

临沂医学专科学校学报 1989年第1期11卷 35-36页

作者：秦中平辛智芳孙立阳临沂地区肿瘤医院外科

本文报告甲状腺功能亢进症合并甲状腺癌10例,占同期手术治疗甲亢病人的2.1%(10/475).男1例,女9例,25～35岁者7例.1例行甲状腺近全切除术,9例行甲状腺大部切除术.全组随访半年至8年均无复发及远处转移.

关键词：甲亢甲状腺肿瘤手术

Differences in nitrous oxide distribution patterns between the Bering Sea basin and Indian Sector of the Southern Ocean

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Acta Oceanologica Sinica 2014年第6期33卷 9-19页

作者： CHEN Liqi ZHANG Jiexia ZHAN liyang LI Yuhong sun Heng College of Ocean and Earth Science Xiamen University Key Laboratory of Global Change and Marine-Atmospheric Chemistry of State Oceanic Administration Third Institute of OceanographyState Oceanic Administration

Nitrous oxide （N2O） distribution patterns in the Bering Sea basin （BSB） and Indian Sector of the Southern Ocean （ISSO） were described and compared. In both sites, the waters were divided into four layers： surface layer, subsurface layer, N2O maximum layer, and deep water. Simulations were made to find out the most important factors that regulate the N2O distribution patterns in different layers of both sites. The results showed that in the surface water, N2O was more understaturated in the ISSO than the BSB. This phenom- enon in the surface water of ISSO may result from ice melt water intrusion and northeastward transport of the Antarctic surface water. Results of the rough estimation of air-sea fluxes during the expedition were （-0.34±0.07）-（-0.64±0.13） μmol/（m2·d） and （-1.47±0.42）-（-1.77±0.51） μmol/（m-2·d） for the BSB and the ISSO, respectively. Strongly stratified surface layer and temperature minimum layer restricted exchange across the thermocline. The N2O maximum existed in higher concentration and deeper in the BSB than the ISSO, but their contribution to the upper layer by eddy diffusions was negligible. In deep waters, a concentration difference of 5 nmol/L N2O between these two sites was found, which suggested that N2O production occurred during thermohaline circulation. N2O may be a useful tracer to study important large-scale hydrographic processes.

关键词： nitrous oxide Bering Sea basin Southern Ocean distribution

Long-Term Consistent Recalibration of VIRR Solar Reflectance Data Record for Fengyun Polar-Orbiting Satellites

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Journal of Meteorological Research 2021年第6期35卷 926-942页

作者： Ling sun Hong QIU Ronghua WU Jing WANG liyang ZHANG Peng ZHANG National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081

The visible infrared radiometer(VIRR)is the first instrument with longest measurements equipped on the Fengyun(FY)polar-orbiting *** re-processing of the historic VIRR measurements,long-term(over 20 yr)global data can be integrated from multiple participating VIRRs on a consistent radiometric scale,which are valuable to climate and climate change *** to lack of an onboard calibration system for VIRR,the reflective solar bands must be vicariously *** study applied the multi-site vicarious approach for consistent calibration of the VIRR visible(VIS)and near-infrared(NIR)data,and produced calibration coefficients for five VIRRs on FY-1 C/D and FY-3 A/B/*** data quality was then evaluated with *** reflectance predicted by using the radiative transfer model over multiple invariant desert and ocean targets was used to derive the calibration slope via a weighted fitting scheme,in which the weights are the inverse of the variance from a radiative transfer simulation evaluated with reference to Aqua moderate resolution imaging spectroradiometer(MODIS).The sensor-specific calibration coefficients were derived on a daily basis by using piecewise *** calibration reference of the VIRR solar band record was further traced to the Aqua MODIS Collection 6.1 reference calibration with a systematic correction derived from the Libya4 *** VIRR record was compared with the Aqua MODIS C6.1 calibration over the polar region based on simultaneous nadir overpass *** lifetime relative difference for each sensor are within 3.3%and 4.5%for channels 1 and *** deserts were also employed to evaluate the stability and consistency of the VIRR *** general,the means of the directional and spectral corrected reflectance for each sensor are within 1%of the 20-yr average,implying that the VIRR reflectance of the invariant targets is consistent to within 1%among the sensors for channels 1 and *** VIRR data th

关键词： FY-1 FY-3 visible infrared radiometer(VIRR) reflective solar bands pseudo-invariant calibration sites(PICS) calibration directional model(DM) spectral band adjustment factor(SBAF)

Infl uence of nitrate concentrations on EH40 steel corrosion aff ected by coexistence of Desulfovibrio desulfuricans and Pseudomonas aeruginosa bacteria

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Journal of Oceanology and Limnology 2022年第4期40卷 1448-1461页

作者： Zhihua sun Jiajia WU Dun ZHANG Ce LI liyang ZHU Ee LI Key Laboratory of Marine Environmental Corrosion and Biofouling Institute of OceanologyChinese Academy of SciencesQingdao 266071China Open Studio for Marine Corrosion and Protection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Chinese Academic of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Marine Materials and Related Technologies Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201China

Nitrate addition is a common bio-competitive exclusion(BCE)method to mitigate corrosion in produced water reinjection systems,which can aff ect microbial community compositions,especially nitrate and sulfate reducing bacteria,but its eff ectiveness is in *** investigated the infl uence of nitrate concentrations on EH40 steel corrosion aff ected by coexistence of Desulfovibrio vulgaris and Pseudomonas aeruginosa *** demonstrate that only mixed bacteria or nitrate had little eff ect on EH40 steel corrosion,and nitrate could accelerate the corrosion of EH40 steel through the action of *** corrosion promotion of nitrate was dependent on its concentrations,which increased from 0 to 5 g/L and decreased from 5 to 50 g/*** diff erences were believed to be related to the regulation of nitrate in the growth of bacteria and biofi ***,care must be taken to BCE method with nitrate when nitrate reducing bacteria with high corrosive activity are present in the environments.

关键词： microbiologically influenced corrosion nitrate Desulfovibrio vulgaris Pseudomonas aeruginosa