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1.
纳米ZrO2的合成对负载Ni催化剂的CH4/CO2重整反应的影响   总被引:1,自引:1,他引:1  
采用共沉淀法、醇热合成法和干法分别合成了纳米ZrO2(ZrO2 CP、ZrO2 ET和ZrO2 S),用XRD、 BET、SEM等对其结构和表面性质进行表征,以CH4/CO2重整为探针反应研究了不同方法合成的纳米ZrO2负载Ni催化剂的催化性能,并与载体的物化性质进行了关联。实验结果表明,以干法合成的纳米介孔ZrO2 S具有较大的比表面积(133m2/g)和较好的孔径分布(4.9nm),Ni/ZrO2 S催化剂在CH4/CO2重整反应中表现出较好的催化性能。  相似文献   
2.
PVC disulfide (2SPVC) was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC's specific area is 36.1 m2·g-1 tested by stand BET method, and granularity experiment gives out the particle size of d0.5= 11.3μm. With SEM (Scanning Electron Microscope) experiment the surface morphology and particle shape of 2SPVC were observed. Cyclic voltammetry (scan rate: 0.5 mV·s-1) shows that 2SPVC experience an obvious S-S redox reaction in charge-discharge process. When 2SPVC was used as cathode material for secondary lithium battery in a 1 mol·L-1 solution of lithium bis(trifluoromethylsulfonyl) imide (Li(CF3SO2)2N) in a 5:45:50 volume ratio mixture of o-xylene (oxy), diglyme (DG) and dimethoxymethane (DME) at 30℃, the first discharge capacity of 2SPVC is about 400.3 mAh·g-1 which is very close to its theoretical value (410.5 mAh·g-1) at a constant discharge current of 15 mA·g-1. It can retain at about 346.1 mAh·g-1 of discharge capacity after 30 charge-discharge cycles. So 2SPVC is a very promising cathode candidate for rechargeable lithium batteries.  相似文献   
3.
吴任平  阮玉忠  于岩 《结构化学》2005,24(9):1096-1100
1 INTRODUCTION The reactivity of activated alumina adsorbent is closely related to its specific surface area: the larger the specific surface area, the better its activity and adsorbent capability are. However, in reality, the prac- tically available specific surface area or effective spe- cific area has relationship with its pore structure[1]. Since many reactant molecules are difficult to enter the pores to react with whose radius is shorter than certain critical value, the increase of p…  相似文献   
4.
The title compound (4,4'-H2bipy)[CdBr4]·H2O 1 has been synthesized via hydrothermal reaction and characterized by X-ray diffraction. The crystal belongs to monoelinic,space group P21/c with a=8.260(3), b=23.926(7), c=9.774(2) (A), β=106.777(9)°,C10H12Br4CdN2O, Mr=608.26, V=1849.4(9)(A)3, Z=4, Dc=2.185 g/cm3, S=1.005, μ(MoKα)=9.814 mm-1, F(000)=1128, R=0.0646 and wR=0.0989. The crystal structure analysis of 1reveals that the title compound features an isolated structure, based on discrete 4,4'-H2bipy moieties and lattice water molecules which are linked by hydrogen bonds together with tetrahedral cadmium atoms terminally coordinated by four bromine atoms.  相似文献   
5.
1 INTRODUCTION In recent years, a great deal of interest has been focused on two-photon initiated photopolymeri- zation (TPIP) exploring some periodical microstruc- tures by means of TPIP[1~3]. The technique will have wide applications in many fields, such as 3D optical mmory[4] and a fabrication of coupling gra- ting in the polymeric waveguide[5], and especially the fabrication of three-dimensional photonic crys- tal[6]. In this work, effective initiator is a key for TPIP. At pre…  相似文献   
6.
This research work was proposed to study the antimicrobial activity of the silver nanocoated fabric with the purpose of producing good dressing and clothing material. We synthesized simple, ecofriendly, cost‐effective and sustainable silver nanoparticles by using the aqueous extract of Allium cepa L. Here, A. cepa L. acts as a good reducing and capping agent that produced stable silver nanoparticles having particle size of range 36 ± 1 to 98 ± 2 nm, Poly dispersiblity index 0.234 ± 0.61 to 1.023 ± 0.33 and Zeta potential ‐12 ± 1.5 mV to ‐26 ± 1.2 mV. The effect of temperature and extract volume used was considered for optimization of synthetic procedure. The nanocoated fabric was characterized for morphological study, size (using transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE‐SEM) and zeta‐potential (Zeta Potentiometer). The presence of functional groups were observed by using attenuated total reflection‐Fourier transform infrared (ATR‐FTIR) and Raman spectroscopy. The crystallinity and structural property of the synthesized silver nanoparticles were studied in terms of Powder X‐ray diffraction (PXRD). An IC50 value and zone of inhibition was studied which demonstrate that the silver nanocoated fabric have an excellent antibacterial property against Gram‐negative (Escherichia coli) and Gram‐positive (Staphylococcus aureus) bacteria. Further nanocoated fabric material was washed (with function of time 0, 10, 25, and 50 laundry cycles) and still retained their anti‐bacterial activity towards both strain. Initially there was 52 μg/ml of silver nanoparticles on the cotton fabric but after 50 laundry cycle in 500 ml of distilled water the fabric showed 92% efficiency against gram positive and 90% efficacy toward gram negative bacteria. It was found that 4.16 μg/ml nano particles leached in case of S. Aureus and 5.2 μg/mL silver nanoparticles leached in case of E. coli. Nanocoated fabric material synthesized using green synthesis was found to be economical with good resistance to washing.  相似文献   
7.
A new compound of 4,4'-diamino-N,N'-diethyl bisbenzenesulfamide (C18H26N4O4S2,Fw = 426.55) has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to the monoclinic system, space group P21/c with a = 10.0623(9), b =13.6759(13), c =15.5309(14) (A),β = 100.482(2)°, V= 2101.6(3)(A)3, Dc = 1.348 g/cm3, F(000) = 904,μ = 0.285 mm-1, Z = 4, the final R = 0.0512 and wR = 0.1363 for 3485 observed reflections with I >2σ(Ⅰ). The structure of the title compound is pseudo secondary axisymmetric, and the two sulfamide-groups show distorted tetrahedral configurations.  相似文献   
8.
A novel cross-linking process using two high molecular weight aromatic poly(thioether)s,which were synthesized by the reactions of 4,4′-thiobisbenzenethiol with 4,4′-difluorobenzophenone and 4,4′-difluorodiphenylsulfone,respectively, and commercially available lower molecular weight poly(p-phenylene sulfide)was investigated.These reactions were carried out in bulk by the addition of silver tetrafluroborate andα,α′-dibromo-p-xylene at 190℃over a period of 45 min. Furthermore,the same procedure could be modified to cross-link compression-molded films of these three polymers.The thermal and solubility behaviors of these polymers before and after cross-linking reactions,are presented.  相似文献   
9.
建立了超声萃取-高效液相色谱法(HPLC)同时测定人造革中7种苯并三唑类紫外线吸收剂UV-P、UV-326、UV-327、UV-329、UV-350、UV-320和UV-328含量的方法。该方法以甲醇为萃取溶剂,超声萃取人造革中的苯并三唑类紫外线吸收剂,萃取液经处理后直接进行HPLC分析,外标法定量。在信噪比(S/N)=3的条件下,UV-P、UV-326、UV-327、UV-329、UV-350的检出限均为0.05mg/kg,UV-320、UV-328的检出限均为0.10 mg/kg。在3个不同加标浓度水平下,各组分的平均加标回收率为88.19%~98.32%,相对标准偏差(RSD)为0.61%~3.74%。该方法简便快捷、灵敏度高,可用于人造革中苯并三唑类紫外线吸收剂的测定。采用该方法对市售人造革样品进行测定,结果在6个样品中检出了不同浓度水平的UV-P和UV-329。  相似文献   
10.
A substituted polyacetylene bearing a furan ring, poly(2-propynyl 2-furoate) (PPF), was synthesized for the first time with palladium acetylide complex catalysts in CHCl3 at 60℃ to give a soluble and stable polymer with a yield of ca.75%. Some features for polymerization of 2-propynyl 2-furoate are described and discussed. The resulting polymer was characterized by IR, GPC and ^1H-NMR analysis.  相似文献   
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