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31.
热辐射光子对高能粒子的影响   总被引:3,自引:1,他引:2  
从热辐射和高速粒子的康普顿背散射出发,结合热辐射规律,探讨了热辐射对高能粒子的影响,给出了由于热辐射造成的高能粒子的能量损失、功率损失、光阻力和光压的表达式。结果显示:由于热辐射造成的高能粒子的能量损耗、功率损失、光阻力和光压正比于温度的4次方,正比于高能粒子Lorentz因子的平方。本文还通过计算得出热辐射对高能粒子的影响可以忽略。  相似文献   
32.
A polymer-stabilised blue-phase liquid crystal display (PSBP-LCD) with double-sided protrusion (DSP) electrodes structure is proposed. The oblique electric field between the protrusion electrodes inside both top and bottom glass substrates can induce more isotropic-to-anisotropic transition in the polymer-stabilised blue-phase liquid crystal (PS-BPLC) medium through Kerr effect than using the in-plane switching electrode. For the same electrode width, spacing and cell gap, the transmittance of PSBP-LCD with the DSP electrodes is ~29% higher than that using the IPS electrode.  相似文献   
33.
A novel zinc diphosphonate, Zn[HO3PCH2(C6H4)CH2PO3H] (1) was synthesized from tetraethyl para-xylylenediphosphonate, Et2O3PCH2C6H4CH2PO3Et2, and Zn (AcO)2·2H2O under solvothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction, which reveals that the structure crystallizes in the monoclinic space group C2/c (No. 15), with a = 22.4844(19) Å, b = 6.4361(5) Å, c = 8.1194(7) Å, β = 102.595(2)°, V = 1146.70(16) Å3, T = 298(2) K, Z = 8. The novel three-dimensional (3D) construction is simply built up from linear inorganic chains of corner-sharing four-rings of tetrahedral [ZnO4] and [PO3C] which connected adjacent chains by the organophosphorus ligand para-xylylenediphosphonate. The framework has 10 Å × 4 Å (containing the van der Waals radii of atoms) channels running along the b-axis.  相似文献   
34.
Yang  Xixi  Li  Jie  Yu  Yue  Wang  Junxia  Li  Dongdong  Cao  Ziyang  Yang  Xianzhu 《中国科学:化学(英文版)》2019,62(10):1379-1386
Nanocarrier-mediated photodynamic therapy(PDT) has attracted extensive attention due to its locoregional therapeutic effect,minimal toxicity to normal tissues, and activation of immune system capability. However, it is still unclear how the physicochemical properties of nanocarriers affect their PDT therapeutic efficacies, which could be very different from those for chemotherapy. Herein, to demonstrate the effect of PEG density on PDT efficacy, we synthesized a series of random polyphosphoesters(PPEs) with different PEG contents by regulating the molar ratios of these monomers, and then these PPEs were used to prepare chlorin e6(Ce6)-loaded polymeric nanoparticles with tunable PEG density. Thereafter, the PDT efficacies of these nanoparticles were carefully and comprehensively evaluated. We demonstrate that the moderate PEG density(3.01 PEG/nm~2) of nanocarrier exhibited the best PDT therapeutic efficacy in a mouse model of pancreatic cancer due to its efficient balance of prolonged circulation and tumor cellular uptake.  相似文献   
35.
柱前衍生-超高效液相色谱法测定鱼卵中的17种氨基酸   总被引:1,自引:0,他引:1  
建立了一种快速、灵敏的柱前衍生-超高效液相色谱-光电二极管阵列检测器(UPLC-PDA)测定史氏鲟(Acipenser schrenckii)、达氏鳇(Huso dauricus)和小体鲟(Acipenser ruthenus)鱼卵中17种氨基酸含量的方法。采用6.0 mol/L的盐酸水解鱼卵,提取液经低压浓缩、碱性中和,然后以6-氨基喹啉-N-羟基琥珀酰亚胺基氨基甲酸酯(AQC)为衍生试剂在pH 8.8硼酸盐缓冲溶液中衍生化。采用的色谱分离柱为Waters BEH C18柱(100 mm×2.1 mm, 1.7 μm),流动相为30 mmol/L乙酸铵水溶液(pH 3.5)和乙腈(含0.15%(v/v)甲酸及30 mmol/L乙酸铵),梯度洗脱,流速为0.7 mL/min,在260 nm波长下检测。17种氨基酸在5.0~1000 μmol/L浓度范围内,峰面积与浓度之间的线性关系良好(r2≥0.9950)。以标准加入法测定回收率和相对标准偏差(RSD),在100、500、750 μmol/L的添加水平下,17种氨基酸的平均回收率为75.4%~107.3%, RSD为2.19%~12.3%。以3倍信噪比(S/N>3)计方法的检出限,17种氨基酸的检出限为0.94~4.04 μmol/L。应用该方法检测了3种鲟鳇鱼鱼卵中的17种氨基酸含量。结果表明,该方法简便、准确、快速、可靠。  相似文献   
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