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将硫酸钴、硫酸亚铁在NaOH溶液中与NaHCO3反应制得碱式碳酸盐前驱体 ,后者用 (NH4 ) 2 S2 O8浸渍、干燥 ,再经 5 0 0℃焙烧得到固体超强酸催化剂S2 O2 -8/CoFe2 O4 。产物经XRD、TEM、BET、TG DTA及化学法等检测 ,含硫量 4 5 2 % ,粒径为 4 2nm ,比表面积为 1 4 6m2 /g ,粒度均匀。催化剂的酸强度处于 -1 6 0 2和-1 4 5 2之间。以该固体酸为催化剂 ,由癸二酸和无水乙醇合成了癸二酸二乙酯。最佳反应条件为 :n(醇 )∶n(酸 ) =4 0∶1 0 ,癸二酸 0 1mol,催化剂 1 0 g ,反应时间 2 5h。在此反应条件下 ,酯化率可达 93 6%。  相似文献   
2.
硅胶基质弱阳离子交换剂的合成及蛋清中溶菌酶的分离   总被引:4,自引:0,他引:4  
用间接法合成了硅胶基质弱阳离子交换剂(XIDACE-WCX),详细研究了合成填料的色谱性能,并与商品柱(Shim-Pack WCX-1和Poly CATA)进行了比较。结果表明:合成柱比商品柱具有较高的分辨能力。通过考察合成填料的疏水性、蛋白质的保留值与等电点(pI)的关系、流动相的pH值和盐浓度对蛋白质保留行为的影响,论证了合成填料的离子交换特征。利用合成的色谱填料从蛋清中分离出纯度较高的溶菌酶  相似文献   
3.
尿囊素(1 脲基间二氮杂茂烷二酮—(2,4),allantoin)是一种两性化合物,可作为医药、化妆品、农业等化工原料中间体。通常用硝酸或过氧化氢氧化乙二醛生成乙醛酸后,再在酸催化下由乙醛酸与尿素缩合而成。但采用浓H2SO4、HNO3等作催化剂,产率偏低(<50%),选择性差,产品质量不好,同时设备腐蚀严重,污染环境。用SO2-4/MxOy型固体超强酸催化剂催化合成尿囊素[2 3],仍有产率偏低等不足之处。我们用La3+掺杂改性SO2-4/TiO2体系,合成了稀土固体超强酸催化剂SO2-4/TiO2 La3+,考察了合成尿囊素缩合反应的催化条件,在最适宜的反应条件下,催化…  相似文献   
4.
A star hybrid inorganic-organic perovskite material selected as an outstanding absorbing layer in solar cells benefits from multiple preparation techniques and excellent photoelectric characteristics. Among numerous synthetic processes,uniform, compact, and multi-stack perovskite thin films can be manufactured using vacuum deposition. During sequential vacuum deposition, the penetration ability of the organic molecules cannot be effectively controlled. In addition, the relationship between the thickness of the inorganic seeding layer and the organic molecule concentration for optimized devices using an evaporation-solution method is unclear. In this work, we prepared high-quality perovskite films by effectively controlling the penetration ability and chemical quantity of organic methyl ammonium iodide by monitoring the evaporation pressure and time. Thus, a device efficiency of over 15% was achieved with an all-vacuum prepared perovskite film. For the evaporation-solution method, we reacted different thicknesses of inorganic lead iodine with various concentrations of the organic molecule solution. The inorganic layer thickness and organic molecule concentration showed a linear relationship to achieve an optimum perovskite film, and an empirical formula was obtained. This work noted the key parameters of two intercalation reactions to prepare perovskite films, which paves a way to deliver a device that enables multi-layered structures, such as tandem solar cells.  相似文献   
5.
We present the fabrication of flexible Cu(In,Ga)Se2 (CIGS) solar cells on a polyimide (PI) sheet with and without Na incorporation. A sodium element is incorporated into the CIGS absorber by using a NaF precursor after Mo back contact deposition. X-ray diffraction patterns show that the (112) preferred orientation of the as-grown GIGS films is decreased by Na incorporation. The secondary phase of (Inx,Gal-x)zSe3 is observed for the CIGS films with Na. There is no significant difference in the grain size with and without Na incorporation from surface and cross-sectional SEM images. Additionally, the increase of carrier concentration and decrease of resistivity of CIGS absorber are induced by Na doping. Finally, the flexible CIGS solar cells on PI sheets with efficiency close to 11%, containing Na, are achieved. The improvement of cell efficiency can be attributed to the modified electrical properties of the CIGS film by Na incorporation.  相似文献   
6.
尿囊素(1-脲基间二氮杂茂烷二酮-(2,4),allantoin)是一种两性化合物,可作为医药、化妆品、农业等化工原料中间体.通常用硝酸或过氧化氢氧化乙二醛生成乙醛酸后,再在酸催化下由乙醛酸与尿素缩合而成.但采用浓H2SO4、HNO3等作催化剂,产率偏低(<50%),选择性差,产品质量不好,同时设备腐蚀严重,污染环境.用SO2-4/MxOy型固体超强酸催化剂催化合成尿囊素[2-3],仍有产率偏低等不足之处.我们用La3+掺杂改性SO2-4/TiO2体系,合成了稀土固体超强酸催化剂SO2-4/TiO2-La3+,考察了合成尿囊素缩合反应的催化条件,在最适宜的反应条件下,催化合成尿囊素的产率可提高至74.5%,且工艺简单,易回收并可多次重复使用.  相似文献   
7.
纳米复合固体超强酸S2O2-8/CoFe2O4催化合成癸二酸二乙酯   总被引:7,自引:0,他引:7  
催化酯化反应;纳米复合固体超强酸S2O2-8/CoFe2O4催化合成癸二酸二乙酯  相似文献   
8.
The effects of working pressure on the composition, structure and surface morphology properties of CuInSe2 (CIS) films selenized with a plasma-assisted selenization process is investigated. Higher selenium content, better crystalline quality and much more regular surface particles compared to the others are found in the CIS film with 40 Pa working pressure. A Cu(In,Ga)Se2 device fabricated with the optimized plasma-assisted selenization process is demonstrated to be better than our previous result. After discussion, the reason for these phenomena is attributed to the compromise of electron temperature and plasma density.  相似文献   
9.
采用甚高频等离子体增强化学气相沉积技术, 基于优化表面形貌及光电特性的溅射后腐蚀ZnO:Al衬底, 将通过调控工艺参数获得的器件质量级高速微晶硅(μupc-Si:H )材料(沉积速率达10.57 Å/s)应用到微晶硅单结电池中, 获得了初始效率达7.49%的高速率超薄微晶硅单结太阳电池(本征层厚度为1.1 μm). 并提出插入n型微晶硅和p型微晶硅的隧穿复合结, 实现了非晶硅顶电池和微晶硅底电池之间的低损电连接, 由此获得了初始效率高达12.03% (Voc=1.48 eV, Jsc=11.67 mA/cm2, FF=69.59%)的非晶硅/微晶硅超薄双结叠层电池(总厚度为1.48 μm), 为实现低成本生产太阳电池奠定了基础.  相似文献   
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