多核金属磺化酞菁催化下的环己烯环氧化反应

尝试使用９种多核金属磺化酞菁催化环已烯的环氧化反应，结果表明它们对环已烯在氧气作氧源的环氧化反应有催化作用，通过正交试验，发现以多核磺化酞菁镍（Ⅱ）、多核磺化酞菁钴（Ⅱ）和多核磺化酞菁铁（Ⅲ）的催化活性为佳。     

Coordinate registration algorithms for over-the-horizon radar

1. INTRODUCTION Over-the-horizon radar, which works in shortwave band,performs over-the-horizon wide area surveillance by reflecting via ionosphere. A significant problem is the phenomenon of multi-path propagation[1], which arises from the presence of layers or regions of relatively high electron density in the ionosphere. Radar signals scattered from the same target arrive at the receiver via different propagation paths. Presently, the common method in OTHR tracking system is multi-pat…     

Marinamide, a novel alkaloid and its methyl ester produced by the application of mixed fermentation technique to two mangrove endophytic fungi from the South China Sea

For a long time, terrestrial microorganisms are abundant natural pharmaceutical resource for human, but it becomes more and more difficult to find new species and microorganisms with special functions from land as the research goes on. Consequently, the s…     

Theoretical study of spin-orbit coupling and zero-field splitting in the spin-forbidden two-state reaction between cobaltacyclopentadiene and isocyanate

The two-state reaction mechanism of CpCo(C_4H_4)with isocyanate on the triplet and singlet potential energy surfaces has been investigated at the B3LYP level.A study is described for the computation of spin-orbit coupling of triplet state of the minimal energy crossing point(CP)with their singlet states and of the zerofield splitting(ZFS)parameters of the triplet states,including the full one-and two-electron terms of the BreitPauli Hamiltonian.There are two key crossing points along this two-state reaction pathway.The first crossing point—CP2 exists near~1B.The reacting system will change its spin multiplicity from the triplet state to the singlet state near this crossing region.Although the spin-orbit coupling interaction and ZFS D-tensor of the CP2 region are very strong,the reaction system will occur the reverse intersystem crossing from T_1 to S_0.Therefore,its spin-flip efficiency may be lower.The second crossing point,CP3will again change its spin multiplicity from the singlet state to the triplet state in the Co-Cr bond activation pathway,leading to a decrease in the barrier height of~1TS(CF)from19.5 to 9.5 kcal/mol(1cal=4.182 J),and the efficiency of intersystem crossing from S_0 to T_1 is high because the larger spin-orbit coupling(SOC)matrix elements will result in the overpopulations of the three sublevels of T_1(3.30×10~(-1),3.32×10~(-1),and 3.38×10~(-1),respectively).     

基于对象感知的城市物流服务需求调研方法

为了有效获取真实有用的物流服务决策信息,确实提高城市物流需求预测的精度、效度,文中采取感知研究、举例研究、实证研究等方法,在分析物流服务需求的特征及传统调研方法的无效性的基础上,进行了服务需求调研方法的要素构建与过程剖析,并提出了基于对象感知的物流服务需求凋研方法体系,最终阐明了合适的感知对象和有效的感知方法对获取城市物流服务真实需求的重要性.     

综合考虑安全性和经济性的料场边坡开挖方案优选

保证安全性和经济性是料场开挖的主要目标.基于这两个目标,以有限元软件ANSYS建立料场边坡的三维网格模型,在综合考虑现场地质条件、位移、应力、塑性区、安全系数和开挖方量等影响因素基础上,采用有限差分程序FLAC3D对开挖边坡的整体稳定性进行计算;并对考虑不同开挖高程和开挖坡比的4种开挖方案进行对比分析,为工程施工提供优选方案.研究表明:在优选方案下,开挖边坡稳定性能够得到保证,弧形马道的圈顶部分应该采取加固措施.     

冷放空天然气火灾爆炸事故影响范围模拟

针对冷放空作业中的意外火灾、爆炸事故,许多研究单一从冲击波超压方面考虑伤害范围,一旦发生火灾,热辐射强度也非常强,研究不同影响因素下火灾的热辐射伤害范围十分必要。首先,分析放空压力6 MPa和放空速率20×10⁴m³/h时冷放空天然气火灾的热辐射影响范围和冲击波超压影响范围,然后,模拟不同放空速率和不同放空压力下热辐射的影响范围和冲击波超压的影响范围。结果表明,在模拟工况下,放空压力对热辐射强度影响更大,热辐射导致的轻伤距离最远达到269.72 m;在模拟工况下,放空速率对冲击波超压影响更大,冲击波导致轻伤的最远距离达到198.00 m。在实际工程中,控制放空压力和放空速率对减轻意外火灾爆炸事故的后果极为重要。     

部分和模1(mod 1)分布渐近均匀性的收敛速度

设｛Ｘj｝是独立同分布随机变量序列,｛Ｓn｝是其部分和序列,ξ（Ｓn）表示Ｓn的小数部分,本文讨论了ξ（Ｓn）渐近Ｕ［０,１）均匀分布的收敛速度,即估计supB∈B［０,１)｜P(ξ(Ｓn)∈B)-P(U∈Ｂ)｜。     

含氧添加剂碳酸二甲酯降低轻型直喷柴油机碳烟的研究

为了研究含氧燃料对发动机性能和排放的影响,在一台Ｆｏｒｄ７６ＰＳＮＡ轻型直喷柴油机上,以发动机台架试验的方法,研究了碳酸二甲酯作为含氧燃料添加剂对对烟度和发动机性的影响。结果表明,在发动机燃油和燃烧系统不变的条件下,随着ＤＭＣ在柴油中添加比例的增加,排气烟度逐步下降。热效率提高,但发动机功率略有下降。     

K-N黑洞视界极点处二级无限小邻域的度规

利用极限方法得到了Ｋｅｒｒ－Ｎｅｗｍａｎ（Ｋ－Ｎ）黑洞视界极点处二级无限小领域的时空度规,并且证明这个时空度规是以常角速度转动的Ｒｉｎｄｌｅｒ度规。