400GeV/c pp碰撞半单举带电粒子赝快度分布测量

利用CERN NA27合作组提供的LEBC泡室照片,测量了400GeV/c pp碰撞产生的带电粒子多重数为8—12的赝快度分布,并用结团模型分析了在固定总多重数时质心系前向半球的多重数分布.结果表明结团的平均大小与是否考虑领头粒子效应有关.     

固相微萃取/GC直接测定废水中的三种氯酚

研究了运用固相微萃取／GC直接测定水中的三种氯酚的方法，得到了分析三种氯酚的SPMF最佳萃取条件。选取聚丙烯酸酯（PA）萃取头，水溶液调pH=2,并用NaCl饱和，室温下在持续磁力搅拌下直接萃取40min，纤维萃取头在260℃脱附5min。所建立的方法适于快速、方便地测定水中三相氯酚，无须浓缩和预处理。     

Fe-Ni-B-O纳米合金的合成及其催化制氢性能的研究

Preparation and catalytic performance of Fe-Ni-B-O nano-alloy having crystal-palpus structure has been studied. Black powder was synthesized by reducing mixture solution of Fe²⁺, Ni²⁺ with KBH₄ as reducing agent and polyethylene glycol as dispersant. Fe-Ni-B-O nano-alloy of crystal-palpus structure was obtained after hydrogen reduction of black powder. TEM shows that crystal-palpus length is 200～400 nm, diameter is 2～4 nm. The analytic results indicate that the total content of Fe and Ni is 86.6%, B is 5.08%. The alloy exhibits excellent catalytic performance. Hydrogen generation rate can approach 100% especially when pH is 8.     

酞菁铜与Q-CdS超微粒子界面的光致电荷转移研究

半导体超微粒子与有机分子界面的光致电行转移过程是当前光化学和材料科学研究的一个活跃领域［‘，2］；研究的目的主要有两个方面，一是研究半导体超微粒子表面光致电行转移的特性；二是研究有机分子对超微粒子的光敏化作用．目前，超微粒子的功能化研究日益深入，其独特的光     

空气—乙炔焰中钇对镱的增感效应及其分析应用

研究了在盐酸介质中钕，钇，镧，铕，以及高氯酸介质中钇对空气－乙炔火焰原子吸收光谱法测定镱的增感效应，建立了钇作增感剂和干扰抑制剂，直接测定富钇混合稀土浓集物与氧化钇粗产品中镱的新方法。     

固定HCG抗体膜的跨膜电位

高分子膜作为一项新兴技术,在很多领域得到日益广泛的应用.近十几年,随着生物工程和生物传感器的迅速发展,高分子生物功能膜的研究倍受重视.高分子生物功能膜是采用固定化技术,将具有分子识别功能的材料(如酶、抗原、抗体等)固定在高分子膜上而制得的.在固定化膜表面发生的生物化学反应,可以引起膜的荷电状态的变化,从而导致跨膜电位的变化。有关固定化膜的报导较多,但主要限于固定化的方法及其应用方面的研究,而有关高分     

纳米尖晶石LixMn2O4的制备与电化学性能表征

Nano-spinel Li_xMn₂O₄(0.6 ≤x≤ 1.0) was synthesized by two steps of coprecipitation and calcination. The influences of calcination temperature, time and Li/Mn ratio on the crystal structure and the particle size of Li_xMn₂O₄ were investigated. It was shown that the higher the calcination temperature, the more complete the crystal structure, and the larger the particle size. Moreover, the influence of calcination time on the crystal structure was insignificant when it was more than 3h at 700℃. With the increase of x in Li_xMn₂O₄ in the range of 0.6～1.0, the d111 and lattice parameter a increased first and then decreased. The electrochemical properties of nano-spinel LiMn₂O₄ using as cathode material of lithium-ion battery were studied. The low discharge capacity might be due to the irreversible capacity loss brought by the large surface area and lattice vacancies of the nano-spinel.     

含湿相变粗糙多孔材质的热质耦合分形研究

多孔材质复杂的内部结构和含湿状态对传热和传质特性有着重要意义,其热质耦合传递过程广泛存在于能源开发和工程隔热等领域。不同于在多孔材质理想状态下对传热和传质特性的单方面分析,该文将孔道的分布参数、粗糙表面、含湿状态和相变等因素考虑进去,运用分形理论推导出了含湿相变粗糙表面多孔材质的渗流系数和耦合等效导热系数的表达式。结果表明,渗流系数与面积分形维数、含湿饱和度呈正相关,与相对粗糙度、迂曲分形维数呈负相关;耦合等效导热系数与渗流系数、相变量呈正相关,与相对粗糙度呈负相关。此外,结果还表明,相变量以及相变引起的气体膨胀压强差对热质耦合传递也有着重要影响。     

CT、MRI对良恶性甲状腺结节的鉴别价值

本文探讨了计算机断层扫描（CT）、磁共振成像（MRI）对良恶性甲状腺结节的鉴别价值。方法：选取2015年3月至2018年3月本院收治的甲状腺结节患者150例，依据病理结果分为恶性48例、良性102例，所有患者均给予CT、MRI检查，分析CT、MRI对良恶性甲状腺结节的鉴别价值。结果发现，MRI总病灶、形态不规则、边界不清/毛糙、信号/密度不均检出率明显高于CT，MRI钙化灶检出率明显低于CT，差异有统计学意义（P<0.05），CT、MRI淋巴结转移检出率比较，差异无统计学意义（P>0.05）；在鉴别良恶性甲状腺结节的敏感度、特异度、准确度中，CT为79.17%、74.51%、76.00%，MRI为83.33%、80.39%、81.33%，CT联合MRI为95.83%、96.08%、96.00%，CT联合MRI明显高于CT、MRI，差异有统计学意义（P<0.05）。说明CT、MRI可作为鉴别良恶性甲状腺结节的重要方法，CT对钙化灶有较高的分辨能力，MRI对软组织及小病灶有较高的分辨能力，CT联合MRI可有效提高其鉴别价值。     

UV LASER INITIATED STEREOSELECTIVE HOMOGENEOUS CATALYSIS POLYMERIZATION OF PHENYLACETYLENE

In this paper, the stereoselective homogeneous catalysis polymerization of phenylacetylene by using two kinds of catalysts W(CO)_5CH_3I and W(CO)_4I_2 produced from UV laser photolysis of W (CO)_6 in CH_3I, I_2—C_6H_6 and CHI_3—C_6H_6 respectively was studied. The effects of laser energy, laser irradiation time and lifetime of catalyst on the polymerization of phenylacetylene were discussed. The photoproducts of W (CO)_6 in CH_3I, I2—C_6H_6 and CHI_3—C_6I_6 were determined by IR spectra. The structures of polyphenylacetylene obtained by W (CO)_5CH_3I and W (CO)_4I_2 catalysts were characterized by IR spectra and ~1H NMR spectra.