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1.
通过熔融盐法制备CuCl_2插层的石墨层间化合物(CuCl_2-GICs),探讨了加热时间、反应物配比对CuCl_2-GIC产物的阶结构、表面形貌及导电性的影响.结果表明,产物含有主阶为1阶的混阶石墨层间化合物和一定量的石墨;延长反应时间有助于增强插层效果;反应物配比对产物的阶结构组成影响较小.插层后的石墨发生了膨胀,在片层的边缘分布着较多的CuCl_2颗粒;制备的CuCl_2-GICs中CuCl_2为非化学计量比,其中[Cl~-]离子不足.CuCl_2-GICs的电导率较石墨原料有所提升,最大提升80%.  相似文献   

2.
首次提出采用水下电弧放电法一步合成氯化镍石墨插层化合物(NiCl2-GICs)。合成插层化合物所用的母材为光谱纯石墨棒,插层剂为NiCl2。运用X射线衍射(XRD)分析和表征了6阶NiCl2-GICs的结构。通过X光电子散射(XPS)对NiCl2-GICs的研究发现其结合能发生了变化,表明在NiCl2和石墨中存在着电子的授受行为,并且Cl原子和C原子之间存在一定的键合作用。据此可以推测,NiCl2-GICs中与碳原子层最靠近的插层原子为Cl原子。研究结果表明,对NiCl2-GICs来说,这是一种简单可控的合成方法。  相似文献   

3.
采用混合熔盐法,以CuCl2,FeCl3为客体材料,粒径1—10μm天然鳞片石墨为主体材料,合成出2,3阶结构的三元石墨层间化合物CuCl2—FeCl3—GICs.简述其制备工艺,应用XRD,SEM,EDS对产物的晶体结构、表面形貌及元素组成进行测试表征,并检测和分析其电磁传导性能.测试结果表明CuCl2—FeCl3—GICs是一种新型轻质导电材料.  相似文献   

4.
用金属钾还原不同阶结构的FeCl3-NiCl2石墨层间化合物前驱体制备了石墨结构层包覆铁镍纳米粒子材料(GEINP)。用四端电极法表征了样品常温电阻率以及电阻率随温度的变化规律,用古埃磁天平法测定了样品的磁化率。结果表明,GEINP电阻率高于原料石墨,呈半导体导电特征,表现为弱磁性,磁化率为10^-2量级。  相似文献   

5.
以CdCl2·2.5H2O,Na2SeO3和NaBH4为反应物,制备3-巯基丙酸稳定的CdSe量子点.研究了加热回流时间、镉和硒的物质的量及镉和3-巯基丙酸的物质的量之比等实验条件对CdSe量子点光谱性能的影响.采用紫外-可见光谱、荧光光谱、X射线粉末衍射和高分辨透射电镜等分析手段,对量子点的光学性能和结构进行表征.结果表明,反应时间、镉和硒的物质的量及镉和3-巯基丙酸的物质的量之比等实验条件对CdSe量子点的光谱性能有明显影响;不同条件下制备的量子点的荧光发射峰的半峰宽保持在35~40 nm范围内;所得CdSe量子点为立方晶型.在pH值为11.0,且nCd∶nSe∶nMPA=1∶0.2∶1.1的条件下,回流90 min制备的量子点的荧光量子产率值可达16.1%.  相似文献   

6.
采用直接一步法回收废旧锂离子电池中的三元正极材料LiNi0.5Co0.2Mn0.3O2,将拆解得到的三元废料经分离、热解处理后进行酸浸,对酸浸溶液进行元素测定后补加Ni、Co、Mn源,使其物质的量之比符合n(Ni)∶n(Co)∶n(Mn)=5∶2∶3. 调整后的溶液直接与草酸钠溶液进行共沉淀,得到草酸盐前驱体,最后与锂源混合,烧结得到三元再生正极材料. 结果表明:再生正极材料的首次放电容量最高达162 mAh/g,充放电100次后的容量保持率接近88%. 但如果材料中杂质元素含量过高,则会对材料电化学性能造成负面影响. 该方法避免了传统方法中将金属元素逐一分离回收所造成的资源浪费和能源损耗,且制备得到的材料具有较高附加值,具有良好的商业化应用前景.  相似文献   

7.
以乙二醇和丁酮为原料,NH4Fe(SO4)2.12H2O为催化剂合成丁酮乙二醇缩酮。通过正交实验得出的适宜反应条件为:固定丁酮的物质的量0.2mol,丁酮与乙二醇的物质的量之比为1.0∶1.6,NH4Fe(SO4)2.12H2O用量占反应物总量的4.3%,反应时间为2.5h,带水剂环己烷用量20mL.在此反应条件下,丁酮乙二醇缩酮的收率为68.1%.  相似文献   

8.
由于Fe,Co,Ni元素密集面上的原子与石墨层面上单号原子间距相近,常用作触媒,使石墨在较低压力和温度下直接转化为金刚石,异相界面上电子密度的大小和差异直接影响其结合能力.笔者应用余瑞璜教授的固体与分子经验电子理论,对Fe,Co,Ni,C的价电子结构进行了键距差(BLD)分析,发现γ-Fe处于B种杂化第12阶, Co 在第12 阶,Ni在第10 阶,C在第6 阶.计算出γ-Fe(111),Co(0001),Ni(111),C(0001)晶面的平均共价电子密度(简称电子密度)分别为38.272 8 nm - 2,54.603 5 nm - 2,54.766 6 nm - 2,76.334 0 nm - 2.作为触媒,Co 和Ni优于Fe.  相似文献   

9.
以FeCl3.6H2O,FeCl2.4H2O和NH3.H2O为原料,在超声波辅助下,用水热法合成了纳米磁性Fe3O4粒子,借助X射线衍射仪(XRD)、透射电镜(TEM)仪及振动样品磁强计(VSM)对产物Fe3O4进行分析,结果表明,当反应物物质的量之比(n(Fe^3+)/n(Fe^2+))为1.75,pH=13得到的前驱物,控制水热合成温度为140-160℃,水热处理时间为3-5 h时,可制备出纯相的反尖晶石结构的Fe3O4纳米微粒,随着水热合成温度的升高和时间的延长晶体发育越完整,平均粒径越大.磁性测量表明,饱和磁化强度和矫顽力也随着Fe3O4纳米微粒平均粒径的增大而增大.  相似文献   

10.
目的以自制的复合无机盐Fe2(SO4)3.Na2S2O8为催化剂,氯乙酸和乙醇为原料合成氯乙酸乙酯.方法研究了氯乙酸与乙醇的摩尔比、催化剂用量、环己烷的用量、反应时间等因素对产品收率的影响,并用红外光谱(IR)、元素分析对产物氯乙酸乙酯进行了表征.结果与结论复合无机盐Fe2(SO4)3.Na2S2O8是合成氯乙酸乙酯的良好催化剂,适宜的反应条件如下:氯乙酸与乙醇的摩尔比为1∶2.0,催化剂用量为反应物总质量的2.5%,环己烷用量12 mL,反应时间1.5 h,氯乙酸乙酯的收率可达85.61%.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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