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Interaction of NPK Fertilizers During Their Transformation in Soils: Ⅲ. Transformations of Monocalcium Phosphate

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Pedosphere 2004年第3期14卷 379-385页

作者： wanghuo-yan zhoujian-min CHENXiao-Qin duchang-wen StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）

Interactions of N, P and K fertilizers in soil-plant systems are widely recognized. This study focused on the transformations of monocalcium phosphate (Ca(H2PO4)2) (MCP) with co-application of ammonium and potassium fertilizers in three different soils. The results showed that after 1 d incubation a large portion of the MCP applied in the paddy,calcareous and red soils became the water-insoluble form and the recoveries of P applied as Olsen P varied greatly in these three soils. Application of ammonium sulfate ((NH4)2SO4) (AS) or potassium chloride (KC1) reduced WSP significantly in the soils with AS more effective than KC1 in the calcareous soil, while the reverse occurred in the red soil. Meanwhile, in the paddy soil, co-application of the two fertilizers reduced WSP more than when the fertilizers were applied individually. The co-application of AS with MCP in the paddy and calcareous soils significantly reduced Olsen P, but the opposite occurred in the red soil. The experiment on the effect of different accompanying anions showed that the ammonium fertilizers (PNC1 and PNS) reduced WSP more effectively than the corresponding potassium fertilizers (PKC1 and PKS) in the calcareous soil due to the difference of the cations, whereas in the red soil, the chlorides reduced WSP more effectively than the sulfates. Overall, co-application of ammonium or potassium fertilizers with MCP significantly decreased availability of P from MCP during its transformation in soils, especially when MCP was applied in combination with ammonium in the calcareous soil.

关键词：铵交互作用单羟基磷酸钙土壤学钾施肥工艺

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油橄榄幼嫩茎段组培快繁技术研究

四川林业科技 2024年第4期45卷 20-25页

作者：姜丽琼浣杰徐志萍何周建李文俊成都市农林科学院成都611130 巴中市恩阳区农业农村局四川巴中636064 四川大学生命科学学院成都611130

以阿贝基纳优良单株幼嫩茎段为试验材料,通过对油橄榄外植体灭菌、基本培养基、生长调节剂等因素对油橄榄组织培养技术影响的研究,试验结果表明:使用75%乙醇30 s、0.1%HgCl_(2) 10 min进行外植体消毒处理时获得率最高,达36.15%;改良MS... 详细信息

以阿贝基纳优良单株幼嫩茎段为试验材料,通过对油橄榄外植体灭菌、基本培养基、生长调节剂等因素对油橄榄组织培养技术影响的研究,试验结果表明:使用75%乙醇30 s、0.1%HgCl_(2) 10 min进行外植体消毒处理时获得率最高,达36.15%;改良MS培养基适宜外植体诱导芽萌发,最佳增殖培养基为改良MS+6-BA 4.0 mg·L^(-1)+NAA 0.5 mg·L^(-1)+TDZ 0.5 mg·L^(-1),诱导率为65.3%,最佳生根培养基为1/2MS+ABT 0.6 mg·L^(-1)+IBA 0.2 mg·L^(-1),生根率90%,活性炭浓度最佳添加浓度0.5 g·L^(-1),蔗糖最佳添加浓度30 g·L^(-1)。

关键词：油橄榄组织培养快繁技术

Lake Sediments from Dianchi Lake:A Phosphorus Sink or Source?

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Pedosphere 2004年第4期14卷 483-490页

作者： GAOLi yanGHao zhoujian-min LüJun-Jie StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）.

Dianchi Lake is a highly eutrophic lake in southwestern China where phosphorus (P) is the limiting element for eutrophication and where lake sediments play an important role in the P cycle. One hundred and eighteen sites were sampled throughout Dianchi Lake in 2002 to investigate the P loading of the lake sediments, while fresh surface sediments were studied in the laboratory to clarify its role for phosphorus. The results showed that concentrations of total phosphorus (TP) in sediments were very high, with a maximum value of 6.66 g kg-1, and decreased with sediment depth. P adsorption on surface sediments was rapid with adsorption amounts higher in acidic than in alkaline conditions. The release experiments showed that P release increased as pH rose from 7.0 to 10.5. Additionally, compared with aerobic conditions, P release was much higher under anaerobic conditions, especially with low P content in the lake water. At present, the sediments in Dianchi Lake still function as a sink for phosphorus at high P levels in lake water. However, if the external P load was reduced and P content in lake water became low, the sediment would have a large potential for P release under anaerobic conditions.

关键词：湖泊污染沉积物吸附性磷富营养

Ammonia Volatilization Losses from Urea Applied to Wheat on a Paddy Soil in Taihu Region, China

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Pedosphere 2005年第1期15卷 59-65页

作者： FANXiao-Hui SONGYong-Sheng LINDe-Xi yanGLin-Zhang zhoujian-min InstituteofSoilScience ChineseAcademyofSciencesNanjing210008China

Ammonia volatilization losses from urea applied as a basal fertilizer and a top dressing at tillering stage in a wheat field of Taihu Region, China, were measured with a micrometeorological technique. Urea as fertilizer was surface broadcast at 81 (low N) and 135 (high N) kg N ha-1 as basal at the 3-leaf stage of the wheat seedling on December 2002, and 54(low N) and 90 (high N) kg N ha-1 as top dressing on February 2003. Ammonia volatilization losses occurred mainly in the first week after applying N fertilizer and mainly during the period after basal fertilizer application, which accounted for more than 80% of the total ammonia volatilization over the entire wheat growth period. Regression analysis showed that ammonia volatilization was affected mainly by pH and NH4+-N concentration of the surface soil and air *** volatilization flux was significantly correlated with pH and NH4+-N concentration of the surface soil and with daily air average temperature and highest temperature. Thus, application of urea N fertilizer to wheat should consider the characteristics of ammonia volatilization in different periods of N application so as to reduce ammonia losses.

关键词：氨挥发尿素小麦栽培管理施肥方法

基于风冷散热的锂离子电池外部冷却模式与内部热物性特征的耦合分析

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华南理工大学学报（自然科学版） 2022年第2期50卷 121-128页

作者：安周建赵亚兵敏政时天禄张东兰州理工大学能源与动力工程学院/甘肃省流体机械及系统重点实验室甘肃兰州730050

锂离子电池因其优异的性能而广泛应用于储能系统以及新能源汽车的动力源。基于锂离子电池热物性特征以及运行条件选择合理的热管理模式,是确保锂离子电池安全性的重要手段。文中分别构建了基于风冷散热的圆柱形单体锂离子电池以及相应... 详细信息

锂离子电池因其优异的性能而广泛应用于储能系统以及新能源汽车的动力源。基于锂离子电池热物性特征以及运行条件选择合理的热管理模式,是确保锂离子电池安全性的重要手段。文中分别构建了基于风冷散热的圆柱形单体锂离子电池以及相应的电池模组模型,从最高温度、最大温差以及温度分布均匀性等方面探讨了热导率各向异性对电池冷却性能的影响。结果表明,锂离子电池内部的热量传递过程以径向导热热阻为主导,直接决定单体电池内部温差以及电池模组中不同单体电池之间的温度分布均匀性。从电池结构设计的角度而言,为了提高温度均匀性,在确保能量密度的前提下应尽量减小电池层状方向的尺寸。

关键词：锂离子电池风冷散热热导率各向异性最高温度最大温差

产业集聚与居民住房支付能力——基于省级面板数据的实证研究

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南京审计大学学报 2018年第6期15卷 39-46页

作者：赵敏马周剑河海大学商学院江苏南京211100

基于我国31个省区市2006—2016年的面板数据,考察产业集聚与居民住房支付能力之间的关系,结果表明:地区之间第二产业发展不平衡的现象已有所改观,但在房价收入比方面地区差异依然较为明显,东中部地区居民面临的住房压力较大;产业集聚和... 详细信息

基于我国31个省区市2006—2016年的面板数据,考察产业集聚与居民住房支付能力之间的关系,结果表明:地区之间第二产业发展不平衡的现象已有所改观,但在房价收入比方面地区差异依然较为明显,东中部地区居民面临的住房压力较大;产业集聚和居民住房支付能力呈显著的倒U型关系。在产业集聚初期,居民住房支付能力和产业集聚之间表现出显著的正向关系,但当产业集聚达到临界值时,居民住房支付能力和产业集聚的二次项之间呈显著的负向关系,产业集聚开始对居民住房支付能力起反作用。此外,人口密度、就业人员工资、环境污染情况对居民住房支付能力具有显著的反向作用,而能源工业固定资产投资的增加能够提高居民住房支付能力。

关键词：产业集聚居民住房支付能力区位熵房价收入比房地产市场财政支出供给侧改革产业结构调整

The Gravitational-wave physics Ⅱ: Progress

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Science China(Physics,Mechanics & Astronomy) 2021年第12期64卷 18-67页

作者： Ligong Bian Rong-Gen Cai Shuo Cao zhoujian Cao He Gao Zong-Kuan Guo Kejia Lee Di Li Jing Liu Youjun Lu Shi Pi Jian-min Wang Shao-Jiang Wang yan Wang Tao yang Xing-Yu yang Shenghua Yu Xin Zhang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Department of Astronomy Beijing Normal UniversityBeijing 100875China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100080China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory for Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study(HIAS)University of Chinese Academy of SciencesHangzhou 310024China MOE Key Laboratory of Fundamental Physical Quantities Measurements Hubei Key Laboratory of Gravitation and Quantum PhysicsNational Precise Gravity Measurement Facility(PGMF)Department of Astronomy and School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China Asia Pacific Center for Theoretical Physics Pohang 37673Korea Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of EducationShenyang 110819China Department of Physics Chongqing UniversityChongqing 401331China

It has been a half-decade since the first direct detection of gravitational waves, which signifies the coming of the era of the gravitational-wave astronomy and gravitational-wave cosmology. The increasing number of the detected gravitational-wave events has revealed the promising capability of constraining various aspects of cosmology, astronomy, and gravity. Due to the limited space in this review article, we will briefly summarize the recent progress over the past five years, but with a special focus on some of our own work for the Key Project "Physics associated with the gravitational waves" supported by the National Natural Science Foundation of China. In particular,(1) we have presented the mechanism of the gravitational-wave production during some physical processes of the early Universe, such as inflation, preheating and phase transition, and the cosmological implications of gravitational-wave measurements;(2) we have put constraints on the neutron star maximum mass according to GW170817 observations;(3) we have developed a numerical relativity algorithm based on the finite element method and a waveform model for the binary black hole coalescence along an eccentric orbit.

关键词： gravitational wave gravitational-wave cosmology gravitational-wave astronomy numerical relativity

2015—2018年贵阳市男男性行为者HIV感染状况及性行为特征分析

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中国艾滋病性病 2019年第8期25卷 812-815,819页

作者：潘庆礼周健朱焱袁飞佘敏李劲贵州医科大学公共卫生学院贵阳550025 贵阳市疾病预防控制中心贵阳550003

目的了解2015—2018年贵阳市男男性行为者(MSM)艾滋病病毒(HIV)感染状况及性行为特征,为针对性地预防控制MSM的HIV感染提供依据。方法以2015—2018年每年4—7月份在贵阳市参加艾滋病哨点监测的MSM为研究对象,进行一对一问卷调查,并采集... 详细信息

目的了解2015—2018年贵阳市男男性行为者(MSM)艾滋病病毒(HIV)感染状况及性行为特征,为针对性地预防控制MSM的HIV感染提供依据。方法以2015—2018年每年4—7月份在贵阳市参加艾滋病哨点监测的MSM为研究对象,进行一对一问卷调查,并采集静脉血进行HIV、梅毒抗体检测。结果 2015—2018年共有1 003名MSM参与研究,平均年龄(27.94±6.74)岁(18~59岁),<45岁者所占比例在95.3%~97.6%之间,86.3%~88.9%未婚,最近6个月有84.0%~99.2%发生同性性行为、3.6%~9.6%发生异性性行为;发生同性肛交性行为时,每次性行为均使用安全套者所占的比例在45.5%~62.2%之间;最近一年有59.6%~77.8%接受过安全套发放与艾滋病咨询与检测服务,接受同伴教育者所占比例在52.4%~61.7%之间,既往检测过HIV者所占比例在55.2%~78.2%之间;2015—2018年HIV阳性检出率在21.6%~25.4%之间,感染者共233人,平均年龄(28.01±7.45)岁(19~59岁),13.0%~26.8%合并梅毒感染,抗病毒治疗率在53.6%~81.3%之间,分别有29/30、36/37、51/52、43/44病毒得到抑制,病毒抑制率为97.5%(159/163)。结论贵阳市MSM的HIV感染检出率较高,合并梅毒感染情况不容忽视,应针对MSM的特征开展艾滋病和性病防控工作及行为干预。

关键词：男男性行为者艾滋病病毒性行为

腹腔镜下Prentiss路径睾丸下降固定术的新认识

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中国微创外科杂志 2022年第6期22卷 463-466页

作者：杨周健杨健唐青松宋鹏刘钧绵阳市中心医院小儿外科绵阳621000

目的总结腹腔镜下Prentiss路径睾丸下降固定术的经验。方法2017年8月~2021年7月我院行腹腔镜下Prentiss路径睾丸下降固定术66例。全身麻醉联合骶管麻醉。脐部切口建立气腹,置入5 mm观察镜,平脐偏下平面稍外侧建立操作通道,检查患侧睾丸... 详细信息

目的总结腹腔镜下Prentiss路径睾丸下降固定术的经验。方法2017年8月~2021年7月我院行腹腔镜下Prentiss路径睾丸下降固定术66例。全身麻醉联合骶管麻醉。脐部切口建立气腹,置入5 mm观察镜,平脐偏下平面稍外侧建立操作通道,检查患侧睾丸血管及输精管发育情况,整体游离精索、输精管及睾丸,经海氏三角钝性建立下降通道,将睾丸牵引下降至阴囊并固定。结果手术时间33~74 min,(40.2±7.1)min。术中出血1~4 ml,(2.0±0.8)ml。腹腔内睾丸5侧,窥视睾丸30侧,腹股沟管内隐睾38侧。合并同侧腹股沟斜疝30例,鞘膜积液2例,行腹腔镜下内环口缝合15例,腹膜外疝囊高位结扎或鞘状突高位结扎术22例。术后患儿麻醉清醒后逐渐恢复饮食,2例患儿切口感染,换药处理后愈合。66例随访4~50个月,中位随访时间20个月,患儿阴囊外观满意,未见复发、睾丸萎缩等表现。结论Prentiss路径延长下降距离,睾丸血供最大程度得以保留,术中注意对睾丸及睾丸血管的保护,正确判断睾丸下降距离。

关键词：腹腔镜隐睾小儿 Prentiss路径