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1.
采用水热法、柠檬酸络合法、模板水热法和固相法合成了不同形貌的BiVO4。利用X-射线粉末衍射、扫描电子显微镜、透射电子显微镜及紫外-可见漫反射吸收光谱等手段对产物进行分析表征。将制备的4种样品进行光催化降解亚甲基蓝实验对比,研究用模板水热法制备的产物在外加H2O2条件下的光催化性能。结果表明:4种方法合成的产物均为单相单斜,形貌有纳米片、微米球等;模板水热法制备的BiVO4光催化活性最高,外加H2O2可以显著提高BiVO4的光催化活性。  相似文献   

2.
以H2WO4、NaOH和Bi(NO3)3·5H2O为原料,通过调节不同pH值和添加表面活性剂CTAB,采用水热法制备出不同形貌的钨酸铋粉体。利用XRD、SEM、UV-Vis对Bi2WO6粉体进行表征。结果表明:pH值对钨酸铋的物相、形貌和光催化和电催化性能均有较大影响;当pH=9.5得到的Bi2WO6粉体结晶度高,禁带宽度为2.61 eV,电催化的可逆性较好,氧化还原电位差仅为0.109 V,光催化活性较高;400 W金卤灯40 min照射下,罗丹明B的降解率达到93.96%。  相似文献   

3.
磷酸镧在发光基质材料、传感器和电子陶瓷等诸多方面都有广阔的应用前景。以La(NO3)3·6H2O和NH4H2PO4为原料,用水热法在不同pH值和添加剂条件下合成纳米单斜相LaPO4粉体。利用X射线衍射、透射电镜、扫描电镜对合成产物进行表征,测试产物的电催化性能。结果表明:pH值为2.0条件下的产物为纳米棒状,结晶优于pH值为5.0的产物,添加剂降低了产物的结晶度,所有条件下合成的产物均显示良好的电催化活性。  相似文献   

4.
以[Cu(tu)]Cl·1/2H2O纳米线作为自牺牲模板在室温下成功制备出形貌良好、纯度高的多孔硫化铜纳米管(PCSNTs)(硫脲=Tu)。利用X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线能谱仪(EDS)和矢量网络分析仪(VNA)对样品的晶体成分和晶相结构、化学元素价态、微观形貌、元素种类和电磁参数进行分析测定。根据传输线理论,计算样品的反射损耗RL;同时,对PCSNTs/石蜡复合物的微波吸收机理和PCSNTs的形成原理进行分析讨论。结果表明,PCSNTs/石蜡复合物在厚度为2.2 mm时,表现出极强的微波吸收能力(在15.67 GHz时,RL=-45.02 d B),有效吸收(RL﹤-10 d B)频宽为4.75 GHz(13.25 GHz~18.00 GHz)。本制备方法简便快捷,产品纯度高、形貌均一,可用于工业化生产。自牺牲模板法是一种制备中空纳米结构的策略。  相似文献   

5.
低烟雾信号特征的无硫黑火药研究   总被引:1,自引:1,他引:0  
崔庆忠  焦清介  陈燕  刘帅 《兵工学报》2010,31(10):1333-1336
采用重结晶法制备了K0.333(NH4)0.667NO3复盐,运用扫描电镜(SEM)、X射线衍射(XRD)能谱和差热分析(DSC)等方法对复盐的微观形貌和晶体结构进行了表征。运用最小自由能原理,以燃烧温度、燃烧热、平衡态固相产物含量为目标函数,计算了K0.333(NH4)0.667NO3/C12H4O2体系燃烧热力学参数,设计出低烟雾输出点火药配方,对优化后配方的火焰感度、燃烧热效应进行了对比测试。结果表明:两种氧化剂达到了在分子间的均匀混合,晶型有序性高,热分解特征温度降低。与KNO3/C12H4O2点火药相比,K0.333(NH4)0.667NO3/C12H4O2点火药的火焰感度、燃烧热效应的降低值小于10%,而燃烧固相产物含量大幅度降低,烟雾信号特征减弱,对1.06μm激光的衰减率下降了73.9%。  相似文献   

6.
纳米TiO_2/碳纳米管复合颗粒的制备及光催化降解TNT废水   总被引:1,自引:1,他引:0  
杜仕国  闫军  汪明球  王彬 《含能材料》2014,22(6):862-866
以钛酸丁酯为主要原料,利用胶溶-回流的方法在碳纳米管(CNT)表面制备了纳米Ti O2。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)观察了纳米Ti O2/碳纳米管(CNT)复合颗粒的形貌特征,X射线光电子能谱(XPS)分析显示复合颗粒表面存在Ti—O及—OH基团,Ti2p3/2和Ti2p1/2电子结合能差约为5.7e V。以TNT溶液为目标降解物,研究了复合颗粒的光催化性能,建立了吸附降解的动力学模型,结果表明Ti O2/CNT复合颗粒对TNT溶液的光催化降解符合一级反应动力学方程,在实验范围内降解速率随着TNT溶液初始浓度的增加而增加,降解动力学关系较好地遵循L-H模型。  相似文献   

7.
乳化炸药在爆轰合成纳米氧化物颗粒中的应用   总被引:2,自引:0,他引:2  
根据乳化炸药的配方原理,结合爆轰法制备纳米氧化物颗粒的实践,提出一种用于爆轰合成纳米氧化物颗粒的乳化炸药的设计思路,制备了含有大量Fe和Mn两种元素的新型乳化炸药。并采用X射线衍射(XRD)和透射电镜(TEM)对该炸药的爆轰产物进行了表征和检测。结果表明,该乳化炸药成功地爆轰合成了具有立方面心尖晶石结构的球形纳米MnFe2O4颗粒。爆轰产物经过280℃热处理1 h后,得到了纯净的纳米MnFe2O4颗粒。  相似文献   

8.
采用水热法成功实现掺杂1%Ag、1%Fe、1%Al、1%Ce、1%Ni、1%Pb的纳米Zn O粉体的制备,通过X射线衍射(XRD)、扫描电镜(SEM)等表征方法,系统分析掺杂元素种类对纳米Zn O材料的结构、形貌及气敏性能的影响。结果表明:掺杂1%Ag、1%Fe、1%Ce、1%Ni的纳米Zn O的结晶度降低;掺杂1%Al和1%Pb的纳米Zn O的结晶度变化较小;未掺杂的纳米Zn O为片状结构;掺杂1%Ag和1%Al的纳米Zn O的形貌为颗粒状结构;掺杂1%Fe、1%Ni和Pb纳米Zn O的材料为六方短柱状;但掺杂1%Ce的Zn O纳米材料与未掺杂Zn O材料相同,具有片状结构。掺杂1%Ag的纳米Zn O对C2H5OH气体的灵敏度最好,对C2H5OH气体和NH3气体有良好的选择性,对C2H5OH气体有较短响应恢复时间和良好的稳定性。  相似文献   

9.
六方BN基陶瓷材料的自蔓延高温合成工艺的研究   总被引:3,自引:1,他引:2  
采用自蔓延高温合成工艺制备了六方 BN基陶瓷件。压坯由无定形 B粉加六方 BN稀释剂或 Si O2 添加剂经冷等静压工艺制成 ,孔隙率为 48%。压坯与 80 MPa N2 反应合成 BN基陶瓷件 ,纯 BN制件致密度为 68% ,BN基制件致密度为 78%。对合成产物进行了 XRD相分析和 SEM断口形貌分析  相似文献   

10.
目前制备二氧化硅纳米管的方法主要有模板法、化学气相沉积(CVD、又称催化裂解法)、激光烧蚀法、水热法、微生物自组装法等。其中模板法对合成大量的纳米管具有灵活性高、可提供通道等优点而成为合  相似文献   

11.
Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.  相似文献   

12.
The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS (geographical information system) data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.  相似文献   

13.
Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.  相似文献   

14.
For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further.  相似文献   

15.
By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux (kernel version 2.6.11 ) is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.  相似文献   

16.
阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅(LTNR)的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明:一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。  相似文献   

17.
By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.  相似文献   

18.
The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.  相似文献   

19.
Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.  相似文献   

20.
A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.  相似文献   

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