基于Le Gall 5/3滤波器提出了一种逐行小波变换方法,处理器从图像节点SD卡逐行读出图像信息,完成多级变换后将变换结果行写入SD卡。该方法 SRAM内存需求低,且仅涉及定点整数乘法、加法及移位操作。应用所提方法对一幅256像素×256...基于Le Gall 5/3滤波器提出了一种逐行小波变换方法,处理器从图像节点SD卡逐行读出图像信息,完成多级变换后将变换结果行写入SD卡。该方法 SRAM内存需求低,且仅涉及定点整数乘法、加法及移位操作。应用所提方法对一幅256像素×256像素仔猪灰度图像进行小波变换实验,结果表明,该方法以合理的定点运算代价换取了3.968 KB的SRAM开销以及8.718 s的时间开销。为基于小波变换的WMSN节点图像压缩奠定了基础,使农业生产图像在低带宽WMSN上高效传输成为可能。展开更多
以氨基-1,2,4-三唑和2-偕二硝甲基-5-硝基四唑(HDNMNT)为原料,通过中和反应合成出两种新型含能离子盐——2-偕二硝甲基-5-硝基四唑3-氨基-1,2,4-三唑盐(3-ATDNMNT)和2-偕二硝甲基-5-硝基四唑4-氨基-1,2,4-三唑盐(4-ATDNMNT),收率分别为9...以氨基-1,2,4-三唑和2-偕二硝甲基-5-硝基四唑(HDNMNT)为原料,通过中和反应合成出两种新型含能离子盐——2-偕二硝甲基-5-硝基四唑3-氨基-1,2,4-三唑盐(3-ATDNMNT)和2-偕二硝甲基-5-硝基四唑4-氨基-1,2,4-三唑盐(4-ATDNMNT),收率分别为95.4%和96.7%;利用FT-IR、1 H NMR、13C NMR、15 N NMR及元素分析等方法对其结构进行表征;采用量子化学方法计算了3-ATDNMNT和4-ATDNMNT的爆轰性能;在标准状态下(膨胀比为70∶1),利用最小自由能原理,分别计算了两种离子盐在丁羟复合推进剂中的能量性能。结果表明,3-ATDNMNT的爆速和爆压分别为8.587km/s和33.58GPa,4-ATDNMNT的爆速和爆压分别为8.693km/s和34.31GPa。以3-ATDNMNT部分取代丁羟复合推进剂中的AP后,丁羟复合推进剂的理论比冲可达2 635.7N·s/kg。以4-ATDNMNT部分取代丁羟复合推进剂中的AP后,当HTPB、Al、AP及4-ATDNMNT各组分质量分数分别为10%、5%、15%及70%时,获得该丁羟复合推进剂的最高理论比冲为2 677.2N·s/kg。展开更多
A hydrolyte of magnesium 7 methoxyl 4′ hydroxylisoflavone 3′ sulfonate ([Mg(H 2O) 6](C 16 H 11 O 4SO 3) 2·10H 2O) was synthesized and its crystal structure was determined by X ray diffractio...A hydrolyte of magnesium 7 methoxyl 4′ hydroxylisoflavone 3′ sulfonate ([Mg(H 2O) 6](C 16 H 11 O 4SO 3) 2·10H 2O) was synthesized and its crystal structure was determined by X ray diffraction analyses. The crystal belongs to triclinic crystal system, space group P ī with cell constants a =0 7359(1) nm, b =0 9935(1) nm, c = 1 6335(2) nm, α =91 16(1)°, β =92 07(1)°, γ =106 53(1)°, V =1 1436(2) nm 3 and Z =1. The results show that the title compound consists of [Mg(H 2O) 6] 2+ , C 16 H 11 O 4SO - 3 and H 2O. Mg(II) is located at the symmetry center of the title compound. [Mg(H 2O) 6] 2+ , C 16 H 11 O 4SO - 3 and H 2O form fourteen kinds of hydrogen bonds. The distance of 0 351 nm between parallel isoflavone rings shows a π π stacking interaction. The hydrogen bonds and π π stacking interaction lead to supramolecular formation with three dimensional network structure. The title compound was also characterized by IR and 1H NMR spectra.展开更多
文摘以氨基-1,2,4-三唑和2-偕二硝甲基-5-硝基四唑(HDNMNT)为原料,通过中和反应合成出两种新型含能离子盐——2-偕二硝甲基-5-硝基四唑3-氨基-1,2,4-三唑盐(3-ATDNMNT)和2-偕二硝甲基-5-硝基四唑4-氨基-1,2,4-三唑盐(4-ATDNMNT),收率分别为95.4%和96.7%;利用FT-IR、1 H NMR、13C NMR、15 N NMR及元素分析等方法对其结构进行表征;采用量子化学方法计算了3-ATDNMNT和4-ATDNMNT的爆轰性能;在标准状态下(膨胀比为70∶1),利用最小自由能原理,分别计算了两种离子盐在丁羟复合推进剂中的能量性能。结果表明,3-ATDNMNT的爆速和爆压分别为8.587km/s和33.58GPa,4-ATDNMNT的爆速和爆压分别为8.693km/s和34.31GPa。以3-ATDNMNT部分取代丁羟复合推进剂中的AP后,丁羟复合推进剂的理论比冲可达2 635.7N·s/kg。以4-ATDNMNT部分取代丁羟复合推进剂中的AP后,当HTPB、Al、AP及4-ATDNMNT各组分质量分数分别为10%、5%、15%及70%时,获得该丁羟复合推进剂的最高理论比冲为2 677.2N·s/kg。
基金ProjectsupportedbytheNaturalScienceFoundationofShaanxiProvince (No .2 0 0 1K11 G5 )
文摘A hydrolyte of magnesium 7 methoxyl 4′ hydroxylisoflavone 3′ sulfonate ([Mg(H 2O) 6](C 16 H 11 O 4SO 3) 2·10H 2O) was synthesized and its crystal structure was determined by X ray diffraction analyses. The crystal belongs to triclinic crystal system, space group P ī with cell constants a =0 7359(1) nm, b =0 9935(1) nm, c = 1 6335(2) nm, α =91 16(1)°, β =92 07(1)°, γ =106 53(1)°, V =1 1436(2) nm 3 and Z =1. The results show that the title compound consists of [Mg(H 2O) 6] 2+ , C 16 H 11 O 4SO - 3 and H 2O. Mg(II) is located at the symmetry center of the title compound. [Mg(H 2O) 6] 2+ , C 16 H 11 O 4SO - 3 and H 2O form fourteen kinds of hydrogen bonds. The distance of 0 351 nm between parallel isoflavone rings shows a π π stacking interaction. The hydrogen bonds and π π stacking interaction lead to supramolecular formation with three dimensional network structure. The title compound was also characterized by IR and 1H NMR spectra.
