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1.
硅基取代环戊二烯基二羰基铁负离子[η^5-RC5H4Fe(CO)2]^-(R=SiMe3,I;Si2Me5,Ⅱ)与铁碘化合物(η^5-C5H5)Fe(CO)2I反应,除得到新的Fe-Fe化合物外,还分离到另两种母体Fe-Fe化合物;桥连化合物(η^5,η^5-C5H4SiM32OSiMe2C5H4)[Fe(CO)2I]2(6)与铁负离子[η^5-C5H5Fe(CO)2]^-(Ⅲ)的反应,仅分离到各  相似文献   

2.
纺锤型γ-FeOOH的合成及其热分析研究   总被引:1,自引:0,他引:1  
采用空气氧化FeSO4与Na2CO3作用生成的Fe(CO3)x(OH)2(1-x)悬浮液体系,通过稀土离子Y3+的掺杂合成出均匀纺锤型铁黄γ-FeOOH微晶.由DTA-TG和XRD分析得出γ-FeOOH随温度升高,发生如下相变过程:γ-FeOOH→γ-Fe2O3→α-Fe2O3.本文还对γ-FeOOH的脱水过程机制和以γ-FeOOH为中间体经热处理制备的纺锤形γ-Fe2O3磁性能作了初步探讨.  相似文献   

3.
木素磺酸铁(Ⅱ)螯合反应特征及其性质研究   总被引:5,自引:0,他引:5  
通过磺化木质素与Fe^2+离子反应的反应特征及其产物木素磺酸铁(Fe-LS)的水溶性、紫外吸收光谱和分子量分布等性质的研究。表明,Fe-LS中的总铁含量高达23.4%(W/W),且表现为Fe(Ⅱ)形态,其水溶性pH而变化,在碱性条件下不生成F3(OH)3沉淀紫外吸收淡谱显示,Fe_LS在205nm处有一明显上峰,在260~280nm间有一肩峰,电观察Fe-LS聚合分子为球形和块状,其主要分子量分布  相似文献   

4.
热处理(Fe0.75Sn0.25)C2O4.nHO可制得单相氮化物γ′-Fe3SnN,其中氮化前的氧化过程,热处理温度和H2/NH3气流比是影响产物的3个关键因素。此氮化物的晶格参数为a=0.38371(5)nm;室温下^57Fe穆堡尔谱为顺磁双峰,低温下谱中显示出铁磁相。  相似文献   

5.
报道了用古埃(Gouy)磁天平法测定K_2[Fe(C_2O_4O_4)_3]3H_2O摩尔磁化率,磁场强度H用CT5型特斯拉计直接测量或由已知单位质量磁化率的莫尔盐(NH_4)_2SO_4,·FeSO_4·6H_2O间接标定,根据测得的摩尔磁化率X_M,求出配合物分子的磁矩U_m和未成对电子数,推断K_3[Fe(C_2O_4)_3]·3H_2O的配位键类型。  相似文献   

6.
均匀纺锤形α—FeOOH微晶制备过程   总被引:3,自引:0,他引:3  
在过程分析的基础上,以Na2CO3作为沉淀剂,在FeSO4溶液中形成Fe(OH)2-FeCO3沉淀,通入空气氧化制备了均匀纺锤形α-FeOOH微晶。研究了碱比、通气量、温度、浓度、搅拌转速以及加料方式等对制备过程以及纺缍形铁黄形态的影响规律,并制备出粒度为0.2μm,轴比为3~4,均匀、无枝杈的纺锤形α-FeOOH粒子。实验验证了该过程为传质控制。  相似文献   

7.
根据综合平衡原理,建立和讨论了一种新型的FeS2-H2O系电势-pH图及该体系中溶液态物质的浓度分布函数单质硫只有较小的稳定区且依赖于溶液中含硫物种总浓度Ct(S)和H2S气体的分压大小,当Ct(S)固定时,分压小于某临界值后单质硫的稳定区将消失Fe2O3(S)和FeS2(S)的稳定区均很大,Fe2O3的稳定性与溶液中含铁总浓度Ct(Fe)有关,而FeS2的稳定性与Ct(S)、Ct(Fe)及H2S气体的分压均有关图3,表3,参4  相似文献   

8.
阐述了以AlCl3·6H2O、Ca(OH)2、漂白精和稳定剂M为原料研制新型混凝-氧化剂(简称ROJ)的制备方法及其作用机理.ROJ用于处理合乳化油废水的实验结果表明;CODcr去除率达80%~85%,油和浊度去除率达90%~95%,与目前常用的混凝剂Al2(SO4)3、PAC、PFS及FeSO4相比,ROJ具有处理效果好,处理费用低的特点.  相似文献   

9.
四甲基环戊二烯与五羰湛铁在二甲苯中加热回流6h,即生成标题化合物1,1与碘在氯仿中反应生成Fe-Fe键断裂在铁碘化物(C5HMe4)Fe(CO)2I,2,1与氯化汞反应生成Fe-Fe键断裂的铁氯汞化物(C5HMe4)Fe(CO)2HgCl3和铁氯化物(C5HMe4)Fe(CO)2Cl4.1与氯化亚锡反应仅分离到铁氯化物4.以元素分析,IR和HNMR谱表征化合物1~4的结构。  相似文献   

10.
Fe(Ⅱ)离子对γ—FeOOH相转化为α—Fe2O3的影响   总被引:5,自引:2,他引:3  
研究了FeSO4浓度及pH值(4~8)对γFeOOH在(99±1)℃下相转化为αFe2O3的影响.结果表明,Fe(Ⅱ)/Fe(Ⅲ)为3%~5%及pH值为近中性时相转化时间最短.指出Fe(Ⅱ)离子对γFeOOH的促进作用为FeOH+吸附在γFeOOH表面使其溶解造成的.  相似文献   

11.
The scales on the surface of yak hair fiber act as barriers during the dyeing process. In order to solve the scale problem and to improve the dyeability of yak hair, yak hair fiber was treated by microwave low temperature plasma (MLTP) in this study. The weight loss and the dyeing properties of the yak hair fiber modified by MLTP were investigated. Scanning Electron Microscopy (SEM) photographs were taken to observe the changes in the surface shape of yak hair fiber before and after treatment. Results showed that after MLTP treatment, the scale structure of yak hair was weakened and damaged greatly and the noticeable changes on the surface shape took place. At the same time, a significant improvement in dyeing properties of yak hair fiber was exhibited.  相似文献   

12.
蛋白酶处理牦牛毛的研究   总被引:3,自引:0,他引:3  
为提高牦毛牛在纺织工业上的利用价值,本文将酶减量加工的工艺应用于牦牛毛进行研究,通过对不同氧化剂,不同蛋白酶的对比研究,发现过氧化氢预处理,再用1398中性蛋白酶处理工艺较适合对牦牛毛的加工。加工后的牦牛毛柔软程度有一定提高,增加了它的使用价值。  相似文献   

13.
蔗渣浆的全无氯漂白工艺   总被引:1,自引:0,他引:1  
对蔗渣浆采用过氧化氢强化的氧脱木素(OP)-螯合预处理(Q)-压力过氧化氢漂白(PO)的短序漂白,探讨了将蔗渣浆漂至82%ISO和用非硅过氧化氢漂白稳定剂代替硅酸钠用于过氧化氢漂白的可行性.研究表明,非硅过氧化氢稳定剂PP-1与PP-2耐高温、耐高压,可用于压力过氧化氢漂白.OP段氢氧化钠用量为2.0%(相对于绝干浆质量,下同)、过氧化氢用量为0.5%,PO段过氧化氢用量为3.0%、PP-1用量为0.1%、PP-2用量为0.5%时,蔗渣浆采用OPQPO流程漂白后,浆的白度可达到85%ISO.而且OPQPO从根本上消除了可吸附有机卤化物的产生;经测定,漂白废水属于可生物降解废水.  相似文献   

14.
In this paper, we have researched TCF bleaching on reed pulp including oxygen delignification, oxygen delignification with H2O2 intensification and H2O2 bleaching. The results show that Op-P bleaching process on NS reed pulp is suitable and the brightness of bleached pulp is up to 82% ISO.  相似文献   

15.
研究桉木硫酸盐浆H2O2强化的氧脱木素效果;研究KMnO4和螯合物对桉木硫酸盐氧漂浆H2O2漂白的改善效果,并对其最佳工艺条件及各种因素对漂白效果的影响进行探讨。结果表明:在氧脱木素过程中加入少量的H2O2,就能起到很好的强化效果;氧漂浆在KMnO4的预处理、DTPA处理后再经过H2O2漂白,可使KP法桉木浆白度达80%以上。  相似文献   

16.
Coral bleaching, which is defined as the loss of colour in corals due to the loss of their symbiotic algae (commonly called zooxanthellae) or pigments or both, is occurring globally at increasing rates, and its harm becomes more and more serious during these two decades. The significance of these bleaching events to the health of coral reef ecosystems is extreme, as bleached corals exhibited high mortality, reduced fecundity and productivity and increased susceptibility to diseases. This decreased coral fitness is easily to lead to reef degradation and ultimately to the breakdown of the coral reef ecosystems. Recently, the reasons leading to coral bleaching are thought to be as follows: too high or too low temperature, excess ultraviolet exposure, heavy metal pollution, cyanide poison and seasonal cycle. To date there has been little knowledge of whether mariculture can result in coral bleaching and which substance has the worst effect on corals. And no research was conducted on the effect of hypoxia on corals. To address these questions, effects of tem- perature, hypoxia, ammonia and nitrate on bleaching of three coral species were studied through examination of morphology and the measurement of the number of symbiotic algae of three coral species Acropora nobilis, Palythoa sp. and Alveopora verrilliana. Results showed that increase in temperature and decrease in dissolved oxygen could lead to increasing number of symbiotic algae and more serious bleaching. In addition, the concentration of 0.001 mmol/L ammonia or nitrate could increase significantly the expulsion of the symbiotic algae of the three coral species. Except for Acropora nobilis, the numbers of symbiotic algae of other two corals did not significantly increase with the increasing concentration of ammonia and nitrate. Furthermore, different hosts have different stress susceptibilities on coral bleaching.  相似文献   

17.
1INTRODUCTIONChina is a country using the most variety of non-wood fiber raw material and is the largest country producing non-wood fiber pulp and paper in the world[1]. Bamboo is one kind of the main non-wood species for papermaking in China. Although the structure of raw materials for papermaking has being adjusted through increasing the proportion of wood pulp and by effectively utilizing waste paper source, non-wood species will still remain an important fiber resource[1,2].At present…  相似文献   

18.
Bleaching of poplar APMP with Formamidine sulphinic acid (FAS) was investigated in this paper.The effects of FAS charges, ratio of treatment on the brightness gain, color reduction and pulp strength were studied. A single-stage FAS bleaching was optimized. Under the conditions of 10 % pulp consistency, 60 minutes time and 70℃ reaction temperature and 0.6 %, FAS (on 0.d.pulp), ratio of FAS to NaOH was 2, we produced a bleached pulp with a brightness of 62.3 %(SBD), a brightness gain of 9.2 units.  相似文献   

19.
1988年4~5月对引进到青海大通牛场和甘南藏族自治州的九龙牦牛的适应性、生长发育、生产性能与行为表现等进行了调查、观察和测定,并对其生理指标进行了测定,结果表明,在青海高原的生态条件下,九龙牦牛是适应的,生长发育良好,并表现出良好的产毛绒性能。  相似文献   

20.
Li  Shu  Yu  KeFu  Chen  TianRan  Shi  Qi  Zhang  HuiLing 《科学通报(英文版)》2011,56(10):1031-1037
Coral bleaching,characterized by a significant loss of symbiotic zooxanthellae,is the primary cause of mass coral mortality and reef degradation throughout the world.The characteristics,processes,and resistance of corals to bleaching varies significantly and is dependent on environmental conditions.We documented a mass coral bleaching event in June 2007 at the Meiji and Zhubi Reefs,Nansha Islands (NS),South China Sea using ecological surveys and measurement of coral zooxanthellae density and sea surface temperatures (SST).More than 35 species of corals (between 0-20 m in depth) were bleached.These bleached corals accounted for 15.6% of total corals in the investigated quadrats.The branching corals Pocillopora and Acropora were the most vulnerable species whereas the massive corals Porites and Favia were more tolerant of the high SSTs.Surprisingly,we found no evidence of bleaching in Agariciidae corals suggesting that this family is resistant to thermal stresses.The bleached corals had lost 72%-90% of their symbiotic zooxanthellae.Furthermore,corals that had no visual signs of bleaching had also lost 31%-53% of their zooxanthellae suggesting that most corals were experiencing the early stage of bleaching.The monthly mean SST during June 2007 was 30.8°C,the highest since 1998.Based on measurements of SST and the Hotspots and DHW data (NOAA),we conclude that it the extremely high SSTs triggered this coral bleaching event.Our results suggest that the previously accepted temperature thresholds used to predict coral bleaching based on satellite data are likely to underestimate the extent and intensity of coral bleaching,at least in the NS.  相似文献   

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