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1.
In this paper, the untreated water from Yangtze River was stored. The turbidity of the water was reduced from 60 NTU to 1 NTU in the first 10 days, but the TOC value reduced only by 0.291 mg/L in 60 days. The organic molecular weight distribution and the organic polarity of storage water was analyzed using UF and XAD resin respectively. It was found that the organic matter, whose molecular weight is less than 4000 dalton, was decomposed and the hydrophilic organic matter was converted into hydrophobic organic matter.  相似文献   

2.
地面环境水体中有机物数量是反映水体有机物污染程度的重要指标。为了了解长江、青弋江芜湖段水体有机物污染状况和水体质量,本文通过对长江、青弋江芜湖段水体周围环境状况现场考察,并分段采取了代表性水体样品,采用高温燃烧—非色散红外吸收法测定了水样总有机碳(TOC)含量,研究了其总有机碳含量变化及其影响因素。结果表明,长江、青弋江芜湖段水体中总TOC含量平均值分别为22.2±4.1 mg/L和22.6±2.7 mg/L,处于较高水平,青弋江个别区域TOC含量超过了40 mg/L。长江、青弋江芜湖段水体TOC的浓度均已超过国家一级标准,青弋江某些河段TOC浓度已远远超过了二级标准。  相似文献   

3.
Organic Fouling and Cleaning of UF Membrane   总被引:1,自引:0,他引:1  
In recent years, the problem of fouling on UF membrane mainly centers on the aspect of organic fouling. The cleaning methods of jam caused by fouling of polysulfone UF membrane, the behavior of organic fouling and the elimination of contamination are studied using several chemicals. This experiment proves that NaClO, H2O2 and NaOH all have some effect on the removing organic fouling of UF membrane, of which the H2O2 has the best effect. Controlling the pH value of raw water can decrease the organic fouling of UF membrane. At the same time, a very good result can be gained in the elimination of organic fouling in a way of combining the water solution of NaOH/NaClO and NaOH/H2O2, which makes the infiltration water flux of UF membrane being restored to its initial value. Moreover, the mechanism of organic fouling formation of UF membrane is analyzed.  相似文献   

4.
Recent researches on the Yangtze River and the Jialing River water in Chongqing section of the Three Gorges Reservoir indicate that the pH value is relatively high and the CODMnconcentration is more than 4.5 mg/L in most of the time. Especially the proportion of dissolved molecule organic is high, as well as the high turbidity during the summer flood period. And the organic contamination is relatively serious. The fuzzy weighted water quality coefficient and hierarchical cluster analysis methods are applied to evaluate and sort the characteristic qualities of two-river water sources. During the research period, the results show that the Yangtze River water source quality is characterized by high turbidity and polluted of summer stage, middle temperature and micro-polluted of spring-autumn stage and low temperature and micro-polluted of winter stage. The Jialing River water source quality is characterized by low turbidity stage, high alga-polluted of early spring stage and high temperature and polluted of winter stage. Due to the various water qualities of two-river water sources at different periods, it is hard to meet the requirement of Standards for Drinking Water Quality (GB 5749-2006) by using traditional water treatment technologies. So the research on enhanced treatment is necessary.  相似文献   

5.
三峡水库水体几种主要阴离子变化特征   总被引:1,自引:1,他引:0  
为了了解三峡水库典型阴离子(Cl-、NO3-、SO42-)随时间、水位的变化特征,选取三峡水库重庆段长江干流涪陵珍溪、忠县石宝寨和开县长江支流汉丰湖为调查点,每2个月1次,连续1年在调查点设置断面分层采集水样,利用离子色谱仪分析水样中典型阴离子Cl-、NO3-、SO42-浓度随时间、水位的变化特征,并初步分析了变化原因。结果表明:全年研究区SO42-浓度为14.67±1.71 mg/L,Cl-浓度为10.66±4.88 mg/L,NO3-浓度为1.89±0.15 mg/L,随季节变化差异均较为显著(CV>43%),且库区水位变化对干流阴离子含量影响较大;涪陵、忠县和开县各不同采样点之间阴离子浓度变化差异也均较为明显(CV>40%)。春季总离子浓度(平均为13.02 mg/L)普遍高于其他3季。  相似文献   

6.
Ca2+、PEG预处理对干旱胁迫下小麦幼苗某些酶活性的影响   总被引:13,自引:0,他引:13  
洪法水  董振吉 《作物学报》1996,22(1):101-106
本文结果表明,Ca^2+、PEG预处理小麦种子具有提高其幼苗RWC及SOD、CAT、POD的活性和降低膜透性的效应,在干旱胁迫下植株生长抑制减轻。随着干旱胁迫的加强、SOD、CAT、POD活性迅速上升并始终维持较高水平,具体表现为浸种处理PEG〉Ca^2+〈H2O;RWC表现为PEG〉Ca^2+〉H2O,植株生长抑制程度表现为PEG〈Ca^2+〈H2O。解除干旱胁迫后,Ca^2+,PEG浸种处理的  相似文献   

7.
王佳  陈钰文 《中国农学通报》2015,31(21):167-176
研究旨在精细化分析江苏空中水汽资源气候特征与开发潜力。笔者应用高分辨率再分析资料,计算资源总量及降水效率,给出空间分布、季节变化、长期变化趋势与模态。结果表明:江苏上空水汽资源(Q)达9223mm,降水效率(P)仅11.4%,近35年减少量约3mm/a,异常主要表现为一致偏多或偏少、南北反相2类空间型。Q与P均呈南多北少的纬向分布,其中淮北Q、P最低,且秋、冬季P持续下降,环太湖与沿海Q、P在春、夏、秋3季均呈下降趋势,宁镇扬Q、P在春、秋季也呈下降趋势。春季Q减少量最大,达4.4mm/a,P南多北少的差异最大达18%,秋季P最低,仅8.4%。可见,江苏空中水汽资源开发潜力巨大,需加强春、秋季开发力度,以及冬季以淮北、夏季以环太湖与沿海为重点区的开发力度。  相似文献   

8.
The immobilized TiO2 film loaded on fiberglass mesh is prepared by sol-gel method, and the analysis result of X-ray diffraction (XRD) shows that the crystalline phase is anatase. On the basis of UV/TiO2 system, the degradation results and effect factors of algal intracellular organic matter(IOM) in Tai Lake are studied. The results show that the degradation of IOM is much harder by photocatalytic oxidation in comparison with humic acid(HA). In 60 min, the IOM degradation of UV254 and DOC are 33.3% and 19.1%, but the HA solution are 96.6% and 57.3% respectively. The reason lies in that IOM is mainly comprised of macromolecular hydrophilic organic matter, containing more amino structures, while HA is strongly hydrophobic organic matter, containing more aromatic structures. Meanwhile, the degradation of IOM is improving as the increase of light intensity to a certain extent; the best degradation rate of IOM appears at pH=6.7.  相似文献   

9.
Comparison of treatment effect is investigated using individual membrane and membrane bioreactor(MBR) for micro polluted water. Hybrid of enhancement technique and MBR is also studied through ammonia chloride, glucose and powdered activated carbon(PAC) added. The results illustrate that the chemical oxygen demand(CODMn) and ammonia-N removal efficiency of individual membrane is 16% and 5% respectively. But the CODMn and ammonia-N removal efficiency of MBR reaches 35.3% and 44.5% respectively. Hybrid of microbial enhancement technique and MBR cannot obtain high removal efficiency for CODMn and ammonia-N by increasing the organic carbon and ammonia-N levels of raw water. 10% PAC renewed raises the CODMn removal efficiency from 35.3% to 50%.  相似文献   

10.
Biofouling has become the focus of RO in water and wastewater treatment. Experimental investigation of RO biofouling mechanism and characteristics in wastewater advanced reuse was carried out by static test and cross-flow dynamic test on a lab-scale membrane fouling simulator(MFS).The experimental results show that the major contributors to biofouling are coli and filamentous bacteria; there usually is no biofouling on the RO membrane surface with the absence of microbial source and nutrient composition; it is easy to cause biofouling on the fouled membrane; the germicidal treatment and the protection in the shut-down period are important for RO. Guidance for the analysis and reduction of biofouling in the practical engineering is provided.  相似文献   

11.
为了探讨混凝法去除水中纳米颗粒的可行性及最佳条件,研究了无机混凝剂(PAC、PFS、PAFC)和有机絮凝剂(CPAM、APAM、NPAM)对TiO2纳米颗粒的去除效果,并考察了投加量、pH、沉淀时间、水力条件及有机无机复配对TiO2纳米颗粒去除效率的影响。单独投加PAC、PFS和PAFC时,三者对应的最高去除率分别为92.51%、84.43%、95.66%。单独投加CPAM、APAM、NPAM时三者对应的去除率仅为61.72%、29.06%、55.37%。复配最佳混凝条件为:投加40 mg/LPAC和3 mg/LCPAM,pH值为9,G值143.5/s,沉淀时间15 min,此时,TiO2纳米颗粒去除率为99.6%。  相似文献   

12.
通过分析不同种类有机肥对植烟土壤主要土壤酶活性和土壤养分的影响,筛选出适宜当地烟区最优的有机肥种类。采用大田试验,在施化肥和芝麻饼肥相同的基础上,设置4个处理,分别为CK(不施有机肥);T1(精制有机肥,1500 kg/hm~2);T2(有机肥料1号,600 kg/hm~2);T3(复方有机菌肥,1500 kg/hm~2)。结果表明:施用精制有机肥能显著提高土壤蔗糖酶[最大值达到11.47 mg/(g·d)]和脲酶活性[最大值达到1.45 mg/(g·d)],对土壤有效磷钾也有显著提高作用,最大值分别达到43.08、472 mg/kg。复方有机菌肥处理显著提高土壤碱解氮含量,长期土壤碱解氮含量达到400 mg/kg。在许昌烟区,相对于对照处理,有机肥和化肥配施能明显提高土壤肥力水平,特别是精制有机肥和复方有机菌肥与化肥芝麻饼肥配施对改善土壤肥力方面效果显著。  相似文献   

13.
Based on the analysis of the water pollution spatial distribution characters of Yangtze River in Chongqing,a new method based on the integration of BP neural network and genetic arithmetic(GA) is proposed.For some shortcomings existed in the standard BP neural network,this method has ultimately overcome these shortcomings by combining the GA with BP artificial neural network through altering stimulating function,adding momentum factor to power value for BP algorithm and introducing genetic arithmetic to searching for the knots of the hidden layer,momentum factor and learning level.Using this method can easily overcome the difficulty of measuring the water prediction model's parameters.GIS is used as a tool for data management and spatial analysis,and the prediction result of the model for the water pollution spatial distribution characters of Yangtze River in Chongqing is visualized and explored with the precision of more than 78%.  相似文献   

14.
利用GGE双标图划分长江流域棉花纤维品质生态区   总被引:4,自引:1,他引:3  
许乃银  李健 《作物学报》2014,40(5):891-898
长江流域棉区棉纤维品质区域特征明显,合理划分纤维品质生态区有助于提高原棉品质和配棉效率。本研究采用GGE双标图的“环境-性状”功能图分析2000-2012年期间长江流域国家棉花品种区域试验中环境与纤维品质性状的互作模式,提出长江流域棉纤维品质生态区划分方案。结果表明,长江流域棉区可划分为“中等品质生态区”、“高长度与比强度生态区”和“低马克隆值生态区”。其中,长江流域中等纤维品质生态区涵盖湖北省江汉平原和鄂东南岗地棉区、河南省与湖北省交界的南襄盆地棉区、湖南省环洞庭湖东部和西部棉区、江西省环鄱阳湖棉区、安徽省沿江与江淮棉区、江苏省宁镇丘陵与沿江棉区和浙江省沿海棉区,纤维品质较好,代表了长江流域的总体水平;高长度与比强度生态区位于湖南省环洞庭湖北部滨湖沃土棉区,纤维长度和比强度优良,而马克隆值偏高;低马克隆值生态区涵盖长江流域最西边海拔较高的棉花熟期早长势较弱的四川丘陵棉区和最东边土壤含盐度较高且棉花长势较弱的江苏沿海棉区,纤维马克隆值达到B级水平,为长江流域马克隆值最好的区域,但纤维比强度水平一般。本研究充分展示了GGE双标图的“环境-性状”功能图在纤维品质生态区划分方面的应用效果,可为长江流域棉花区域化种植和纺织企业合理用棉提供决策支持,也为其他棉区和作物生态区划分研究提供参考。  相似文献   

15.
The present status of water environment in three gorges area of Yangtze River is analyzed in this paper.The importance to enhance water environment protection and ecology environment protection in Three Gorges area of Yangtze River is also discussed in this paper. Some suggestions about water environment protection and ecology environment protection in Three Gorges of Yangtze River are also provided . Finally, the environment constructional targets to let clear water mirror on Three Gorges area of Yangtze River again are put forward.  相似文献   

16.
基尼系数视野下的安徽省水土资源匹配分析   总被引:2,自引:0,他引:2  
为科学地规划区域农业的发展,通过构建区域基尼曲线和计算区域基尼系数,同时选用单位面积耕地所拥有的水资源总量法,对安徽省2000—2012年的水资源和耕地资源进行匹配分析。结果显示:安徽省多年平均水土资源空间匹配的区域基尼系数G=0.4449,水土资源空间匹配状况优于中国(0.5664)、世界(0.5864)平均水平。安徽省水土资源匹配在地市尺度上具有明显空间分异,呈现皖南地区水土资源匹配状况优于江淮之间,而江淮之间又优于皖北地区的水土资源匹配格局。  相似文献   

17.
采用PCR和DNA测序技术研究鄱阳湖水系增殖放流群体与野生群体白鲢的遗传结构和群体遗传学特征,测定了瑞昌、赣江、增殖放流3个群体54尾鲢线粒体控制区全序列935bp,缺失或插入3个碱基,发现41个变异位点,均为简约信息位点,共检出24个单倍型。转换/颠换比为14.344。在邻接树上来自不同地点的鲢混杂分布于各分支,没有出现明显的谱系结构和地理聚群。AMOVA 分析表明变异主要来自种群内,种群间出现显著分化。FST=0.22388也表明遗传变异主要来自种群内。3个群体间的遗传距离为0.01035~0.01634,Fst值为0.08252~0.39171,表明3个群体间存在显著遗传分化。赣江、瑞昌和增殖放流群体的单倍型多样性分别为0.727、0.978、0.947,核苷酸多样性分别为0.00897、0.01135、0.00978,其中瑞昌群体的单倍型多样性与核苷酸多态性在3个群体中最丰富,其次是增殖放流群体,赣江群体单倍型多样性及核苷酸多样性最低,应加以保护。  相似文献   

18.
太湖流域稻麦轮作体系施肥现状分析与对策   总被引:3,自引:1,他引:2  
太湖流域是中国重要的商品粮生产基地之一。为了探讨太湖流域稻麦轮作体系最佳养分管理技术施肥途径,在前人研究的基础上,通过采用文献总结与调查研究的方法,分析太湖流域稻麦轮作体系的施肥现状,指出施肥中存在的问题。结果表明,农户间施肥量差异大,过量与不足现象并存;养分投入不平衡,农民普遍偏施氮肥,磷、钾肥尤其是钾肥使用比例很低,一般不超过氮肥施用量的20%;氮肥施用时期不合理,与作物养分需求不同步。建立、完善和应用集土壤、作物、环境等管理技术为一体的最佳养分管理技术是实现太湖流域稻麦轮作体系生产力持续提高、经济效益和资源高效利用及环境保护多重目标相协调的必然选择。  相似文献   

19.
为了明确长三角地区饲料油菜适宜收获期与晾晒时间,2016-2018年连续2年开展田间试验,终花至角果期刈割5次并于田间晾晒,比较不同刈割期和晾晒天数下饲草产量、粗蛋白含量及水分变化差异。结果表明,与首次刈割(终花期)相比,终花后4到16d刈割饲草鲜重显著增加,饲草干重分别提高了31.93%、41.50%、49.14%和61.43%。随着刈割时间延迟,饲草粗蛋白含量呈下降趋势,末次刈割饲草含水量显著降低(P<0.05)。油菜终花后4d刈割,并于田间晾晒第4和5天时,其鲜草含水量由82.16%下降为71.45%和65.26%。不考虑刈割期,田间原位晾晒3d,平均鲜草含水量由81.00%下降至66.30%。晾晒期间土壤累积温度每增加10°C,鲜草含水量降低2.30%。由此,长三角地区稻茬油菜在终花后4d刈割,饲草鲜产和粗蛋白含量均能达到较优水平,刈割后田间原位晾晒4~5d,可满足青贮水分要求。  相似文献   

20.
为解决‘红地球’葡萄在南方沿海地区设施栽培中存在的着色差、风味淡及设施葡萄园土壤板结、酸化、盐渍化等问题,通过在冬季基肥中增施不同的有机肥,研究其对土壤理化性质、营养状况、植株生长及果实品质的影响。施用碳基生物肥、生物菌肥和菜饼肥均可以明显提高土壤有机质、有效磷和速效钾含量,效果以碳基生物肥最佳,有机质、有效磷和速效钾分别较对照显著提高43.77%、35.45%和57.9%;菜饼肥对土壤微量元素的增加效果最好,交换性钙和镁含量分别较对照显著提高40.58%和13.74%;施用有机肥可以不同程度上降低容重、增加孔隙度、降低土壤含盐量、提高pH,效果以施用菜饼肥最佳。施用有机肥可以增加叶面积,提高枝条木质化程度,施用菜饼肥的叶面积和枝蔓木质化程度分别提高了21.62%和14.31%;施用腐熟菜饼肥的果实综合品质最高,单果重、TSS、固酸比分别提高26.46%、2°Brix和34.20%,经济效益以腐熟菜饼肥和碳基生物肥为最好,每公顷效益分别增加至58794和39456元。施用不同有机肥能不同程度地提高土壤有机质、营养元素含量,降低土壤含盐量、降低容重、增加孔隙度、提高土壤酸碱度,进而促进枝蔓生长、提高品质和效益,综合效果以施用腐熟菜饼肥最佳。  相似文献   

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