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A Simulation Study on Effect of Surface Film-Forming Material on Water Evaporation

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Pedosphere 2001年第1期11卷 67-72页

作者： zhuANG SHUNYAO, YIN BIN and zhu zhaoliang (Institute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (China)) 中科院南京土壤所江苏南京 210008

A greenhouse experiment was conducted to investigate the effect of surface film-forming material (SFFM), a mixture of 16-18-octadecanols by emulsification, on water evaporation. Air-dried soil with distilled water was incubated firstly for 7 days to reestablish soil biological activity and then for another 7 days after treated with SFFM at rates of 0, 1, 2, 4, 6 and 8 g m-2, respectively. Everyday during the 7-day incubation after addition of SFFM, water losses due to evaporation were ~measured by an electronic balance. The rate of water evaporation with the addition of SFFM was reduced significantly compared with the control treatment and the effectiveness of SFFM on water evaporation reduced with time. According to the equation expressions of the effect of SFFM on water evaporation, the half-life of electiveness of SFFM on water evaporation was introduced and calculated to analyze quantitative relationship between the effectiveness of SFFM on water evaporation and the addition rate of SFFM. The calculated half-life increased with the addition rate of SFFM and the confidence of the calculated values of the half-life was high, suggesting that the half-life of effectiveness of SFFM on water evaporation could be described quantitatively and may be helpful for ameliorating application method of SFFM and screening surface-film forming materials in order to improve nitrogen fertilizer use efficiency in flooded rice fields.

关键词： half-life of effectiveness surface film-forming material water evaporation

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中国土壤氮素研究

土壤学报 2008年第5期45卷 778-783页

作者：朱兆良中国科学院南京土壤研究所南京210008

概述了自20世纪30年代以来中国土壤氮素研究的某些进展。主要包括:土壤氮素的本性和氮素肥力,有机肥料氮,农田中化肥氮的去向和氮肥增产效果,农田中化肥氮的损失对环境的影响和农业生态系统的氮素平衡。土壤氮素研究的进展得益于相关学... 详细信息

概述了自20世纪30年代以来中国土壤氮素研究的某些进展。主要包括:土壤氮素的本性和氮素肥力,有机肥料氮,农田中化肥氮的去向和氮肥增产效果,农田中化肥氮的损失对环境的影响和农业生态系统的氮素平衡。土壤氮素研究的进展得益于相关学科的进展。并强调指出,对我国来说,在研究的指导思想上必须高度重视高产与环境保护的协调与统一。

关键词：土壤氮索肥力氮肥有机肥料氮素循环农业和环境

Occurrence of nitrification-denitrification and gaseous nitrogen loss process in flooded rice soil

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Progress in Natural Science:Materials International 2007年第1期17卷 6-10页

作者： NI Wuzhong, LI Jianping and zhu zhaoliang (College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310029, China Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China) [a]Gllege of Environmental and Resmirce Sciences Zheiang University Hangzhou China [b]Gllege of Biosystems Engineering and Food Science Zheiang University Hangzhou China [c]Institute of Soil Science Chinese Academy of Sciences Naning China

Flooding in wetland rice fields soon after transplanting results in displacement of soil air (including O2). Thus any dissolved O2 in the pore water is consumed out by microbial respiration in a short period. Supply of O2 to the flooded rice soil is by diffusion of O2 through the standing floodwater and consumption at the soil-water interface, and by exudation of O2 by rice roots and subsequent diffusion of O2 into the rhizosphere. The greater potential consumption of O2 compared to the renewal rate results in the development of distinct soil layers: oxidized soil layers under soil-water interface and in the rhizosphere, and reduced soil layers or reduced bulk soil. Nitrification in oxidized soils and denitrification in reduced soils have been known. Currently, denitrification in oxidized soils, even in standing floodwater, has also been identified. In this article, we present a modified nitrification and denitrification occurring mechanism in flooded rice soil.

关键词： denitrification flooded rice soil gaseous nitrogen loss nitrification.

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地埋管热泵换热系统热影响半径分析

地质学报 2019年第S01期93卷 226-232页

作者：王涛朱照亮魏善明盛慧斌王楠山东省地质矿产勘查开发局八〇一水文地质工程地质大队济南250014 中国矿业大学资源学院江苏徐州221116 山东省物化探勘查院济南250014

地埋管热泵换热系统是一种在开发利用浅层地热能过程中应用非常广泛的热交换系统。本文依托山东省国土资源厅实施的聊城市浅层地温能调查评价项目,对聊城市某小区内的地埋管热泵换热系统安装温度自动采集监测装置,2016年采集一个完整制... 详细信息

地埋管热泵换热系统是一种在开发利用浅层地热能过程中应用非常广泛的热交换系统。本文依托山东省国土资源厅实施的聊城市浅层地温能调查评价项目,对聊城市某小区内的地埋管热泵换热系统安装温度自动采集监测装置,2016年采集一个完整制冷期的地温变化数据,通过监测地埋管热泵系统换热孔和周边一定距离内监测孔内温度变化,绘制换热孔和监测孔一定时间范围内温度随时间和距离的关系变化曲线,分析换热孔在吸收热量后温度通过土壤介质的传播速率和最大影响半径,从而为实际地埋管热泵换热系统工程设计提供了依据。

关键词：地埋管换热系统换热孔监测孔传播速率影响半径

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45t　EBT高功率电弧炉的喷补工艺

特殊钢 1998年第4期19卷 41-42页

作者：李艾朱照良北满特殊钢公司齐齐哈尔161041

Spraying Patching Technology for a 45 t EBT High Power Electric Arc

关键词：电炉炼钢电弧炉偏心炉底出钢炉壁喷补

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弓形和矩形先导级2D伺服阀动态特性分析

农业机械学报 2020年第2期51卷 418-426页

作者：陈烜阮健刘奎朱兆良赵伟李胜浙江工业大学二维(2D)液压/气动元件及系统工程技术研究中心杭州310023 嘉兴学院机电工程学院嘉兴314001

2D伺服阀基于螺旋伺服的原理将先导级和功率级集成在阀芯上,具有功率密度高和响应速度快的特点,其动态特性易受先导级节流口的影响。本文对弓形和矩形两种先导级结构的2D伺服阀动态特性及其结构参数对动态特性的影响进行研究。首先,阐... 详细信息

2D伺服阀基于螺旋伺服的原理将先导级和功率级集成在阀芯上,具有功率密度高和响应速度快的特点,其动态特性易受先导级节流口的影响。本文对弓形和矩形两种先导级结构的2D伺服阀动态特性及其结构参数对动态特性的影响进行研究。首先,阐述2D伺服阀的结构及工作原理,分别建立弓形和矩形先导级结构2D伺服阀的数学模型;然后,采用数值计算的方法对两种先导级结构2D伺服阀进行仿真分析,获得两者在不同结构参数(斜槽角β、先导级零位开口量h 0)和不同工作压力p s下的阶跃响应特性;最后,搭建2D伺服阀的阶跃特性实验平台,获得弓形和矩形两种先导级结构2D伺服阀的阶跃特性实验曲线,并与仿真结果进行比较。结果表明,在相同结构参数(斜槽角β为82°、先导级零位开口量h0为0.02mm)和20MPa工作压力条件下,2D伺服阀采用矩形先导级结构将阀芯轴向位移对阀芯转角的阶跃响应时间,从弓形先导级结构的3.4ms缩短为1.4ms。将矩形先导级结构应用于以力矩马达作为电-机械转换器驱动阀芯旋转构成的2D电液伺服阀中,当阀芯轴向位移为0.3mm时,其阶跃响应时间为10ms,基本满足2D电液伺服阀对响应速度的要求。

关键词： 2D伺服阀先导级数值计算动态特性

17β-Estradiol protects SD rat retinal neurons from light damage by activating PI3K/Akt and NF-κB signal pathways

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17β-Estradiol protects SD rat retinal neurons from light da...

中国生物化学与分子生物学会第十届会员代表大会暨全国学术会议

作者： Ming Shu Mo Shao Lan Wang Hongbo Li Yan Feng zhaoliang zhu Baoying Wang Ruochen zhu Shuhong Wang Yan Han Xiaorui Yu Department of Genetics and Molecular Biology School of MedicineXi’an Jiaotong University

Our previous studies have proved that the phosphatidylinositol-3-kinase(PI3K)/Akt signal pathway was involved in the neuroprotection of 17β-estradiol(βE2) against H2O2-induced retinal neurons apoptosis in *** aim of this study is to observe whetherβE2 can also protect retinal neurons from light damage in vivo by activating the PI3K/Akt signal *** used 180 to 230 g female SD rats exposed to persistent white light after ovariectomy 2 weeks as experimental model and used Electroretinogram (ERG),DNA ladder,TUNEL,HE staining,Western blotting and Immunofluorescence techniques to investigate the neuroprotection ofβ*** results showed that SD rats were exposed to 8000 lux white light for 12 h resulted in retinal function decrease and photoreceptor cells apoptosis, and 10-4M and 10-5MβE2 by intravitreal injection all significantly enhanced the photosensitive function of retinal by preventing neuronal *** mechanism research found that the neuroprotection ofβE2 involved in increasing the phosphorylation of Akt which was partly blocked by the pretreatment with PI3K inhibitor LY294002 for 30 min beforeβE2 *** cleaved caspase-3 as an activation form of caspase-3 was observed after light damage and the administration ofβE2 can attenuate the activation of caspase-3,while pretreatment with LY294002 can inhibit the attenuation ofβ*** results showed that NF-κB translocated from cytoplasm to nucleus afterβE2 injection,and LY294002 could also inhibit partly this *** present results indicated thatβE2 has a neuroprotective effect against light-induced photoreceptor cells apoptosis,and the PI3K/Akt pathway plays an important role in this neuroprotection,which involved in translocation of NF-κB from cytoplasm to nucleus and inhibited the activation of caspase- 3,but the detailed mechanism of theβE2 neuroprotection is being further study.

关键词： 17β-estradiol retinal light damage neuroprotection apoptosis

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热带亚热带酸性土壤硝化作用与氮淋溶特征

土壤 2020年第1期52卷 1-9页

作者：赵旭蔡思源邢光熹朱兆良土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所) 南京210008 中国科学院大学北京100049

通过室内好气培养和土柱模拟淋洗培养试验,研究了氨基氮肥加入对热带亚热带4种不同性质和利用方式酸性土壤硝化、氮及盐基离子淋溶、土壤及淋出液酸化的影响。4种土壤分别为采自花岗岩发育的海南林地砖红壤(HR)、玄武岩发育的云南林地... 详细信息

通过室内好气培养和土柱模拟淋洗培养试验,研究了氨基氮肥加入对热带亚热带4种不同性质和利用方式酸性土壤硝化、氮及盐基离子淋溶、土壤及淋出液酸化的影响。4种土壤分别为采自花岗岩发育的海南林地砖红壤(HR)、玄武岩发育的云南林地砖红壤(YR)、第四纪红黏土发育的江西旱地红壤(RU)和第四纪下蜀黄土发育的江苏旱地黄棕壤(YU)。结果表明:4种土壤硝化作用大小表现为YU>RU>YR>HR。HR主要以可溶性有机氮(DON)和NH4^+-N形态淋失,YU土壤的氮淋溶形态以NO3^–-N为主,YR和RU土壤的氮淋溶形态NO3^–-N、NH4^+-N和DON兼而有之。盐基离子总淋失量与NO3^–-N淋失量显著正相关,但各盐基离子淋失由于离子本性和土壤性质差异并不完全一致。Ca^2+在缓冲外源NH4+-N硝化致酸和平衡NO3^–-N淋失所带负电荷过程中起重要作用。在阳离子交换量小、盐基饱和度低的土壤(如RU土壤),外源NH4^+-N的硝化和淋失不仅导致盐基离子淋失,而且引发NH4^+-N、甚至是H^+淋失。综上,热带亚热带地区土壤上外源氮输入的增加可能会在更短的时间内导致氮素向系统外的流失,引发环境问题。

关键词：酸性土壤硝化作用氮淋溶盐基离子

甲醇为碳源时C/N对反硝化过程中亚硝酸盐积累的影响

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化工学报 2010年第11期61卷 2938-2943页

作者：曹相生付昆明钱栋朱兆亮孟雪征北京工业大学建工学院水质科学与水环境恢复工程北京市重点实验室北京100124 北京建筑工程学院环境与能源工程学院城市雨水系统与水环境省部共建教育部重点实验室北京100044 山东建筑大学市政与环境工程学院山东济南250101

如何获得稳定的NO2--N作为厌氧氨氧化细菌的电子受体是城镇污水通过厌氧氨氧化途径脱氮的瓶颈问题。为此考虑利用反硝化途径获取稳定的NO2--N。以甲醇为碳源,采用小试装置的SBR反应器,通过控制进水C/N(COD与NO3--N质量浓度比)的策略,研... 详细信息

如何获得稳定的NO2--N作为厌氧氨氧化细菌的电子受体是城镇污水通过厌氧氨氧化途径脱氮的瓶颈问题。为此考虑利用反硝化途径获取稳定的NO2--N。以甲醇为碳源,采用小试装置的SBR反应器,通过控制进水C/N(COD与NO3--N质量浓度比)的策略,研究了反硝化过程中的NO2--N积累的状况。试验结果表明以甲醇为碳源且投加量不足时(C/N<3.2),反硝化过程中和反硝化结束后会产生稳定的NO2--N积累;在C/N不足的前提下,NO2--N积累量随甲醇投加量的增加而增加;进水C/N为2.4～3.2时,可获得约25%的NO2--N积累率;进水C/N为0.8时,NO2--N积累率仅为5.6%;C/N<1时,NO2--N与NO3--N的还原速率随着COD浓度的增加而增加;C/N≥1时,COD浓度不再影响NO2--N与NO3--N的还原速率。

关键词：亚硝酸盐硝酸盐碳源反硝化 C/N 甲醇厌氧氨氧化