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1.
<正> 在评价粘土矿床时,首先需要确定粘土矿物的类型,这对于判定粘土原料的工艺学和工业利用具有很重要意义。粘土(或<0.001mm 级别的矿物)的化学组分主要是 SiO_2、Al_2O_3和 H_2O,此外还常有Fe_2O_3、FeO、MgO、CaO、MnO、K_2O、Na_2O、TiO_2和其它一些元素的氧化物等杂质,同时在化学分析时常常可测出 H_2O~-(吸附水)和H_2O~+(结构水或结晶水)。  相似文献   

2.
采用化学热力学平衡分析方法,应用污泥实测数据模拟计算了污泥掺烧过程中Cl/S/P与矿物质的交互作用,重点模拟研究了Cl/S/P/矿物质交互体系对Cd迁移转化的影响.研究结果表明,污泥掺烧过程含Cl、S及P逸出气体以HCl(g)、SO_2(g)及(P_2O_5)_2(g)形式排放.污泥掺烧含有CaO-SiO_2-Al_2O_3体系中,CaO可以抑制S以SO_2(g)释放,而SiO_2及Al_2O_3对SO_2(g)逸出有促进作用,同时CaO及Al_2O_3可以抑制P的挥发.污泥掺烧过程中SiO_2及Al_2O_3对Cd挥发都有一定抑制作用,但CaO及Fe_2O_3对Cd基本无影响;当Cl存在时,Ti O2和SiO_2对Cd吸附作用减弱,并使Al_2O_3吸附剂失效;当S存在时,可导致吸附剂对Cd中毒,而P可导致Al_2O_3吸附剂失效;Cl-S-P耦合体系中,单一矿物质对Cd迁移转化影响主要受Cl和S控制.SiO_2+CaO+Al_2O_3共存体系中,Cl的存在可导致固体吸附剂SiO_2和Al_2O_3失效;S、S+Cl、S+P、S+Cl+P的存在受控元素为S,并且可以抑制Cd的挥发;P、Cl+P的存在对Cd影响受控元素为Cl,可促进Cd挥发.  相似文献   

3.
风沙运动造成地表沉积物组分发生改变,伴随其沉积物地球化学特征发生改变。选取苏宏图洪积扇扇缘戈壁、沙积洼地地表沉积物,基于X射线衍射仪、扫描电镜能谱仪进行其不同组分矿物、地球化学元素测试。结果表明:风沙运动导致不同地表沉积物的风蚀和风积情况不同,但其均处于化学风化的初、中级阶段,具有相似性;该砂砾质地表不同粒径组分以石英、长石、云母、方解石等矿物为主,各沉积物组分矿物衍射峰强具有显著差异性;该区域不同粒径颗粒化学元素组成以SiO_2、Al_2O_3、Fe_2O_3为主,约占总含量的85%左右,沉积物颗粒粒径越大,SiO_2含量越多,Fe_2O_3、MgO、CaO、TiO_2等氧化物表现为在细颗粒组分中富集,而Al_2O_3、K_2O、Na_2O等随颗粒粒径变化无显著差异。  相似文献   

4.
宋庆良  余灵渊 《环境工程》1991,9(4):46-49,19
<正> 1 前言辰溪县粉煤灰资源丰富,年产生量28000多吨,主要来源于火力发电厂及全县生产生活锅炉烧煤单位。粉煤灰中主要成份,除含有一定量的CaO、SiO_2、Al_2O_3、Fe_2O_3、Na_2O、K_2O、MgO及少量的硫以外,尚含有10~30%的残余炭。多年来,因缺乏综合利用技术,造成粉煤灰在产生单位满负荷堆积,每年至少要发生1、2次粉煤灰污染事故。为彻底解决粉煤灰污染问题,我们进行了多方面的研究和探讨,将它利用到水泥生产行业中去,做生产水泥的燃料。  相似文献   

5.
文摘选登     
<正> 过铝花岗岩(Peraluminous granites)——G.B.Clacke,《The Canadian mineralogist》,1981,Vol.19,Part Ⅰ,PP.1—2(英文) 过铝花岗岩构成花岗岩类的一个化学分支,在这种岩石中,氧化铝与氧化钙、氧化钠和氧化钾的全岩摩尔比值[Al_2O_3/(CaO+Na_2O+K_2O),简写为A/CNK]大于1。具有这种成分的硅酸盐熔体必然要结晶出一组特征的矿物,它们可能包括白云母、高铝黑  相似文献   

6.
本文分析了浙、闽、赣地区产于玄武岩、安山岩、流纹岩、黑曜岩及珍珠岩中玻璃相的拉曼光谱特征,认为酸性火山岩中的玻璃相分子团结构基本上由类似于结晶学上的、但在三维方向完全无序的链状、层状、架状及纯架状网络体组成,而中基性火山岩中的玻璃相结构仅由前三者组成。玻璃相分子团结构与其断健程度(DBB)间受一维延长的链状网络体(Ch)的含量正向控制及三维扩展的纯架状网络体(Ne~*)的含量负向控制,一元回归线性方程、相关系数R、拟合度F,分别是: 经研究,其中的黑曜岩可能是岩浆喷发间歇后的另一次爆溢产物。  相似文献   

7.
苏北海州群云台组上段变火山岩富含碱性长石(60-70%)和钾长石(35-60%),黑云母为富铁黑云母,部分火山岩含霓辉石、萤石等.其岩石地球化学特征:高硅(SiO_2>6.41%),富碱(Na_2O+K_2O8.54%).高钾(K_2O4.52%),低铝(Al_2O_311.88%).贫钙、镁(CaO0.25%,MgO0.13%);富Nb、Zr、Y、Zn和Ga等元素;富REE、LREE和Eu强烈亏损.上述特征与世界和福建魁歧、浙江青田、江苏苏州、山东崂山等A型(或碱性)花岗岩的特征一致,为A型火山岩.其连云港市东部分布区是寻找与海相A型火山岩有关的Sn、W、Zn、Ph、Ag(Au)等华前型块状硫化物矿床和热液矿床的重要靶区.  相似文献   

8.
粤东花岗岩类的SiO_2、K_2O及ALK值偏高,Al_2O_3、Fe_2_O_3、FeO及MgO偏低,ANKC值、Na/K比及CaO、Na_2O含量介于华南改造型花岗岩和同熔型花岗岩之间;负铕异常明显,轻稀土显著富集,中稀土(Tb—Tm)略有亏损;铅同位素高于地幔铅和下地壳铅同位素组成,略低于华南中生代上地壳铅同位素组成;锶、氧同位素具正相关关系,不相容元素比与其他元素间无相关关系。其岩浆起源于上、下地壳间的过渡带,该过渡带由上地壳物质及侵入其中的幔源物质组成,岩浆上升定位过程中,未发生过明显的分异结晶一同化作用。  相似文献   

9.
铁-硅岩石占整个铁矿建造岩层的很大部分,在同一化学组成下具有各种不同的矿物组成。例如,碧玉铁质岩和片岩,其矿物成分很不同,但按硅和全铁的含量却很相近。其他造岩组分的含量是次要的,因此在矿物形成时不起重要作用。一般SiO_2为40—50%;Fe_2O_3为30—50%;FeO为1—25%;MgO为0.1—8%。象Al_2O_3、Na_2O、K_2O这  相似文献   

10.
层状菱铁矿的成因分类,根据其分类基础,可分为两大类型:一是以地质作用和产出特征为背景的定性成因分类;二是以菱铁矿的某些化学组分为标准的定量成因分类。本文推荐一种新的定量分类标准,即利用siO_2—Al_2O_3—CaO+MgO三角图,将层状菱铁矿矿划分为三种成因类型:(1)沉积碎屑岩型层状菱铁矿;(2)海相火山沉积型层状菱铁矿;(3)海相沉积碳酸盐岩型层状菱铁矿。  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

13.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

14.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

15.
Single and joint effects of pesticides and mercury on soil urease   总被引:6,自引:3,他引:3  
The influence of two pesticides including chlorimuron-ethyl and furadan and mercury (Hg) on urease activity in 4 soils (meadow burozem and phaeozem) was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase (up to 13%-21%) in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship (P〈0.05) between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose (ED50) values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.  相似文献   

16.
A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several (halo)aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no (chloro)catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.  相似文献   

17.
A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field > tree land > fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT >1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.  相似文献   

18.
The contribution of aliphatic-rich plant biopolymer to sorption of hydrophobic organic compounds is significantly important because of their preservation and accumulation in the soil environment,but sorption mechanism is still not fully understood.In this study, sorption of 1-naphthol by plant cuticular fractions was examined to better understand the contributions of respective fraction.Toward this end,cuticular materials were isolated from the fruits of tomato by chemical method.The tomato cuticle sheet consisted of waxes (6.5 wt%),cuticular monomer (69.5 wt%),and polysaccharide (24.0 wt%).Isotherms of l-naphthol to the cuticular fractions were nonlinear (N value (0.82-0.90)) at the whole tested concentration ranges.The KodKow ratios for bulk cuticle (TC1),dewaxed cuticle (TC2),cutin (TC4),and desugared cuticle (TC5) were larger than unity,suggested that tomato bulk cuticle and cutin are much powerful solption medium.Sorption capability of cutin (TC4) was 2.4 times higher than the nonsaponifiable fraction (TC3).The 1-naphthol interactions with tomato cuticular materials were governed by both hydrophobic-type interactions and polar (H-bonding) interactions. Removal of the wax and polysaccharide materials from the bulk tomato cuticle caused a significant increase in the sorption ability of the cuticular material.There was a linear negative trend between K_(oc) values and the amount of polysaccharides or fraction's polarities ((N O)/C);while a linear positive relationship between K_(oc) values and the content of cutin monomer (linear R~2=0.993) was observed for present in the cuticular fractions.Predominant sorbent of the hydrophobic organic compounds (HOCs) in the plant cuticular fraction was the cutin monomer,contributing to 91.7% of the total sorption of tomato bulk cuticle.  相似文献   

19.
Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.  相似文献   

20.
Seed induces and promotes the crystallization of calcium phosphate, and acts as carrier of the recovered phosphorus (P). In order to select suitable seed for P recovery from wastewater, three seeds including Apatite (AP), Juraperle (JP) and phosphate-modified Juraperle (M-JP) were tested and compared. Batch and fixed-bed column experiments of seeded crystallization of calcium phosphate were undertaken by using synthetic wastewater with 10 mg/L P phosphate. It shows that AP has bad enduring property in the crystallization process, while JP has better performance for multiple uses, and M-JP is a hopeful seed for P recovery by crystallization of calcium phosphate.  相似文献   

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