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1.
用(NH4)2MoS4,CoCl2,NiCl2,HSCH2CH2SH和Et4NBr在CH3OHCH3ONa溶液中反应,得到了顺(A),反(B)异构体的原子簇化合物[(C2H5)4N]2[Mo2S4(SCH2CH2S)2]的晶体。用X—射线单晶衍射法测定了顺、反异构体簇合物A和B晶体结构,其晶胞参数A为a=2.6044(2)nm,b=1.9886(2)nm,C=2.6302(I)nm,V=13.586nm3,β=93.33°(2);B为a=1.044(2)nm,b=1.4158(2)nm,C=1.1417(2)nm,V=1.638nm3,β=100.47°,经块距阵最小二乘法修正最终得偏离因子R=0.088(A),R=0.089(B)。同时还对簇合物的红外光谱和紫外可见光谱也进行了研究。  相似文献   

2.
借助于固相合成、X射线衍射分析和交流阻抗法测定了BaO-Gd2O3-TiO2体系的相关系、相结构与电性质。发现在研究的部分体系内有两个三元化合物新相:BaGd2Ti4O12属正交晶系,其晶胞参数为:a=1.21372nm,b=2.23265nm,c=0.38195nm,V=1.034970nm^3,Z=4;Ba11Gd4Ti7O31属六方晶系,其晶胞参数为:a=0.59547nm,c=2.9719  相似文献   

3.
水杨醛型腙类试剂测定铝的研究   总被引:4,自引:0,他引:4  
江崇球  唐波 《化学试剂》1997,19(6):353-355
合成了以水杨醛为母体的4种腙类新荧光试剂,并对其与铝的荧光反应性能进行了比较研究,结果表明,5-溴-水杨醛水杨酰腙是一种优良试剂。它与铝在pH5.4醋酸-醋酸铵缓冲溶液中形成13型荧光配合物,其λex=370nm,λem=460nm。建立的分析方法检测下限为1.1ng/mL,相对标准偏差为1.45%。考察了30余种共存离子的干扰情况。直接应用于葡萄糖注射液及常见饮料中微量铝的测定,结果满意。  相似文献   

4.
以CTA氧化残渣中分离出的混合单元苯羧酸为原料,采用改性分子筛为催化剂,合成混合单元苯羧酸二甘醇酯增塑剂。最佳工艺条件为:催化剂用量0.3%,反应温度220℃,反应时间7h.醇:酸=1.3:1(当量比)。  相似文献   

5.
合成了题述试剂SPAHQ,可用其作钴显色剂。生成的红棕色1:4(Co:SPAHQ)螯合物λmax=480nm,ε480=8.1×104L·mol-1·cm-1,Δλ=90nm。0~1.2μg/mLCo2+遵守比尔定律。1~10mg的7种离子和0.035~0.94mg的18种离子不干扰。用于间接分光光度测定VB12,结果与亚硝基R盐法一致。本法既灵敏、选择性也好。  相似文献   

6.
通过缓慢挥发溶剂法得到一种不对称吡喃Weng方酸菁染料的单晶,测定了其晶体结构。其晶系为三斜晶系,空间群为P1,a=0.9228(4),b=1.4122(6),c=0.6124(3)nm,α=93.97(4),β=98.14(5),γ=71.05(4),V=0.7470(6)nm^3,Z=1。用晶体结构数据解释了此不对称染料的^1H-NMR谱。  相似文献   

7.
合成并鉴定了一个新的二安替比林类试剂:二安替比林基-(3-溴)苯基甲烷(DAmBM),研究了它与钒(Ⅴ)的显色条件。在Mn(Ⅱ)和Tween-20存在下,DAmBM与V(Ⅴ)在浓H3PO4介质中产生橙色产物,λmax=490nm。ε=2.44×106L.mol-1cm-1。V(Ⅴ)量在0.1-1.1μg/25ml范围内符合比尔定律。用该体系测定中草药中的V(Ⅴ),结果满意。  相似文献   

8.
借助于固相合成、X射线衍射分析和交流阻抗法测定了BaO-Gd_2O_3-TiO_2体系的相关系、相结构与电性质。发现在研究的部分体系内有两个三元化合物新相:BaGd2Ti_4O_(12)属正交晶系,其晶胞参数为:a=1.21372nm,b=2.23265nm,c=0.38195nm,V=1.034970nm ̄3,Z=4;Ba_(11)Gd_4Ti_7O_(31)属六方晶系,其晶胞参数为:a=0.59547nm,c=2.97197nm,V=0.91263nm ̄3,Z=1。在研究的部分体系内含有13个单相区,25个二相区,13个三相区。测定了相关物相的电导和介电常数,发现BaGd_2O_4与Gd_2Ti_2O_7有很高的介电常数(ε’>200),是很有希望的功能材料。  相似文献   

9.
合成了二安替比林-(3-溴)苯基甲烷,经元素分析、红外分析鉴定。研究了它与铬(Ⅵ)的显色反应,在磷酸介质中,Mn(Ⅱ)和吐温-60存在下,试剂与铬(Ⅵ)生成橙红色化合物,人maX=480nm,ε=5.44×l05L·mol-1.cm-1,铬(Ⅵ)量在0~5.00μg/25ml间符合比尔定律。该体系具有一定的选择性,用于标钢中微量铬的测定,结果满意  相似文献   

10.
高效液相色谱法测定2,4-二氯氟苯   总被引:1,自引:0,他引:1  
应用甲醇:水=90:10为流动相,在Shim-PackC18柱上,以甲苯为内标物,于254nm下检测,建立了以2,4-二硝基氟苯为原料合成的2,4-二氯氟苯的高效液相色谱分析方法。该方法的相对标准偏差为2.1‰。2,4-二氯氟苯进样量在0.4~8.0μg范围内呈良好的线性关系(r=0.9999)。  相似文献   

11.
In this paper,the effects of pore-size of SBA-15 on the adsorption kinetics and equilibrium of large protein molecules Bovine serum albumin(BSA)and lysozyme(LYS)have been investigated.The mesoporous molecular sieve SBA-15 with six different pore sizes were synthesized with P123 triblock copolymer as the template agent,and 1,3,5-trimethylbenzene(TMB)and isopropyl alcohol as the pore-expanding agent.The samples were characterized by N2 adsorption/desorption,Scanning Electron Microscopy(SEM),Transmission Electron Microscopy(TEM)and X-Ray Diffraction(XRD).It is found that BSA and LYS were adsorbed rapidly on SBA-15 materials with large pores.The BSA adsorption capacity of sieve with the pore diameter of 21.4 nm reached 500 mg·g-1 within 25 minutes.However,if the pore diameter was smaller than 14 nm,the BSA adsorption capacity of the sieve was only about 220 mg·g-1.The adsorption equilibrium data fits in the Langmuir model,where the coefficient of effective use of specific area of mesoporous molecular sieve was found to be 0.03,0.18,0.37 and 0.48,corresponding to the pore diameter of 10.1 nm,13.2 nm,15.4 nm and 21.4 nm,respectively.The equilibrium loading amount of LYS on SBA-15 materials with pore size of 15.4 nm could be up to 1000 mg·g-1.The coefficient of effective use of surface area of mesoporous molecular sieve with diameter of 3.9 nm,7.4 nm,10.1 nm,13.2 nm and 15.4 nm was 0.10,0.47,0.56,0.71 and 0.79,respectively.It is also noted that greater pore size of mesoporous molecular sieve would lead to a higher coefficient of effective use of surface area.  相似文献   

12.
针对申家庄煤矿选煤厂粗煤泥含量高引起的浮选尾矿跑粗、高中损、高介耗等问题,结合TBS分选原理及应用效果,采用TBS干扰床分选机对粗煤泥分选系统进行改造。具体措施为:加大原煤脱泥筛入料水冲溜槽的流量和冲洗力度,筛前段加设分流板,提高脱泥筛的脱泥效率;缩短倾斜板浓缩机的倾斜板间距,提高倾斜角度,减少溢流中粗颗粒含量;更换小筛孔筛板,增加喷水设备,提高脱介效率。改造后倾斜板浓缩机溢流中+0.500mm粗颗粒产率由10。10%降为2.10%,改造效果明显;浮选压力明显降低,提高了精煤产率;TBS对粗煤泥分选效果良好,精煤质量和产率均大幅提高;介耗降低1.11kg/t,中损降低4.76%。  相似文献   

13.
采用溶胶-凝胶法在微波条件下制备Ti-MCM-41介孔分子筛,采用SEM、BET、XRD、TEM和FT-IR等对催化剂进行表征,对比MCM-41和水热合成的Ti-MCM-41介孔分子筛,并分析其制备机理,以合成的分子筛为催化剂进行柴油脱硫实验。结果表明,合成的Ti-MCM-41分子筛结构有序,晶形完整,平均孔径约4.5 nm。在每10 mL模型油Ti-MCM-41用量0.2 g、n(H2O2)∶n(苯并噻吩)=4和V(乙腈)∶V(模型油)=1条件下,苯并噻吩的催化氧化活性较高,动态氧化-萃取脱除率最高达93.5%。  相似文献   

14.
Several activated carbons were prepared by carbonizing Saran 872 at different temperatures. The capacity of these carbons to adsorb several hydrocarbons was studied using a gas-chromatographic technique at high temperatures. All the carbons had pores of less than 0.62 nm in size. The sample obtained at 1573K in a He atmosphere had slit-shaped pores which acted as a molecular sieve for cyclohexane. These pores were opened by mild gasification of the sample, resulting in the loss of molecular sieve properties. Heats of adsorption of the hydrocarbons were calculated from the specific net retention volumes. The effect of oxygen surface complexes on hydrocarbon specific net retention volumes was also studied.  相似文献   

15.
陶章峰  赵谦  马艳  贾佳  姜廷顺 《硅酸盐学报》2012,40(10):1466-1472
以正硅酸乙酯为硅源、十六烷基三甲基溴化铵为模板,在氟化物存在的条件下,通过水热法在不同晶化温度和时间下进行复合分子筛Y/MCM-48的合成。利用X射线粉末衍射、Fourier变换红外光谱、N2吸附–脱附、扫描电子显微镜和透射电子显微镜对合成的样品进行表征,同时考察了样品的稳定性及不同晶化时间和温度下样品的晶相。结果表明:在120℃水热晶化36h合成的Y/MCM-48具有良好有序的MCM-48介孔相以及NaY微孔相的双重孔结构,其比表面积高达864 m2/g,平均孔径为2.4 nm。样品经800℃焙烧4 h、100℃水热处理48 h后,复合分子筛的双重孔结构仍然存在。  相似文献   

16.
分析了济三选煤厂重介选煤工艺,说明选煤厂主要存在煤泥水分高,一段底流煤泥量大、洗水浓度高,煤泥重介旋流器入料不稳、介质回收率偏低等问题。通过分析选煤厂水介耗、精中矸磁选机入料和尾矿磁性物含量,说明脱介筛筛板孔径偏大,筛子喷水压力不够,筛子喷嘴易堵,精、中磁选机入料不稳,介质质量差是造成选煤厂介耗高的主要原因。针对上述问题,济三选煤厂通过调整脱介筛筛板孔径,增加脱介筛喷水压力,改造脱介筛喷嘴,改造煤泥重介旋流器和保证介质质量合格等对选煤厂重介生产工艺进行了改造。结果表明:改造完成后,济三选煤厂水介耗明显降低,与2010年相比,2011年6月选煤厂水耗由0.055 kg/t降至0.045 kg/t;介耗由2.710 kg/t降至1.424 kg/t,减少了1.286 kg/t,每年可节约介质1286 t,节省介质费用194万元。  相似文献   

17.
以三乙烯四胺为模板剂,采用水热合成法,以磷酸、正硅酸乙酯、氢氧化铝、乙酸镁及三乙烯四胺为原料,各原料配比为n(P)∶n(Si)∶n(Mg)∶n(Al)∶n(H2O)∶n(TETA)=1∶0.11∶0.38∶0.49∶82∶0.89,在(150~170) ℃、晶化时间24 h和pH=6.0~6.2条件下,合成得到纯度较高和热稳定较好的含镁磷酸硅铝分子筛。采用扫描电子显微镜和粉末X射线衍射对分子筛进行晶体结构和形貌分析,所得分子筛在合成范围内具有较高的纯度和结晶度。DSC-TG热分析表明,分子筛具有较好的热稳定性。对分子筛进行甲醇转化反应评价,结果表明,在载气流速10 mL·min-1、进料体积空速5.0 h-1和300 ℃条件下,甲醇转化反应中气相产物甲烷体积分数可达80%,乙烯和丙烯含量约为13%。通过Vario EL Ⅲ型元素分析仪测定C、N、H和Mg质量分数分别为6.51%、5.53%、3.19%和3.39%。  相似文献   

18.
Ni (or Co)-mesoporous molecular sieve was hydrothermally synthesized from sodium silicate, nickel chloride or cobalt chloride. Cetyltrimethyl ammonium bromide (CTAB) was used as a template. The samples were characterized by means of powder X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature programmed reduction (TPR), Fourier transform infrared spectrosocopy (FT-IR) and N2 physical adsorption. The results show that the long-range ordered Ni (or Co)-mesoporous molecular sieve was synthesized. The as prepared Ni-mesoporous molecular sieve has a specific surface area of 753 m2/g and an average pore size of 3.23 nm, and the pore structure of the as prepared Ni-mesoporous molecular sieve still existed after calcination at 750°C for 3 h or hydrothermal treatment at 100°C for 5 days. On the other hand, the as prepared Co-mesoporous molecular sieve has a specific surface area of 744 m2/g and an average pore size of 4.44 nm. The as prepared Co-mesoporous molecular sieve was transformed into wormhole-like mesoporous structure after calcination at 650°C or hydrothermal treatment at 100°C for 5 days and the mesoporous ordering became very poor after calcination at 750°C for 3 h.  相似文献   

19.
高晓晨 《天津化工》2012,26(4):17-19
本研究以甲醇及甲缩醛为原料、酸性分子筛为催化剂合成聚缩醛二甲醚(PODEn),考察了ZSM-5分子筛的硅铝比、磷改性、粒径尺寸等因素对反应的影响。结果表明,Si/Al为50、P2O5含量为6 wt.%、粒径尺寸为5nm的ZSM-5分子筛催化剂活性较佳,三聚甲醛的反应转化率达到95.2%,PODEn(n=2~4)的选择性为58.0%。  相似文献   

20.
隔舱式多段旋流分级机试验研究   总被引:1,自引:0,他引:1  
为了达到多产品分级目的,设计了一种隔舱式多段旋流分级机;分别采用了筛网式和实体式隔板,在不同的隔板组合和操作参数下进行了试验;结果表明隔舱式多段旋流分级机可依次分离出粗粒、中粒、细粒等多个产品,筛网式隔板可显著减少粗粒产品中的细粒夹带,分级效果较好。  相似文献   

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