Schiff 碱双核配合物的磁性及催化性能的研究

This paper reports the catalytic properties of “porphyrin-like” Schiff base mononuclear complexes MH₂L {M=Mn(Ⅱ), Fe(Ⅲ)Cl, Cr(Ⅲ)Cl, Cu(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ); L=bis[N, N′-ethylene-2, 2′-(phenylmethylene)bis(3,4-dimethylpyrrole-5-aldimino)]} and dinuclear complexes MnML [M=Mn(Ⅱ), Fe(Ⅲ)Cl, Cr(Ⅲ)Cl, Cu(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ)] for cyclohexane monooxygenation with PhIO and magnetic properties of the dinuclear complexes. The magnetic investigations (4～300 K) of the dinuclear complexes revealed that their antiferromagnetic spin exchange with J ranged from -10.49 to -0.482 cm^-1 except MnZnL and antiferromagnetic spin exchange decreased in the following order: Mn^Ⅱ-Cu^Ⅱ > Mn^Ⅱ-Ni^Ⅱ > Mn^Ⅱ-Mn^Ⅱ > Mn^Ⅱ-Fe^Ⅲ > Mn^Ⅱ-Co^Ⅱ > Mn^Ⅱ-Cr^Ⅲ. The results of catalyzed oxidation of cyclohexane indicated that the catalytic property of the dinuclear complex was better than that of the corresponding mononuclear complex. It was found that there was the synergism decreased in the order: Mn-Fe > Mn-Cr > Mn-Cu > Mn-Mn > Mn-Co> Mn-Ni > Mn-Zn. It seems that this synergism increases with the increase of the number of unpaired d electrons and the magnetic exchange between the two metals in these dinuclear complexes.     

采用不定Dogleg路径的非单调自适应信赖域算法解无约束极小化(英文)

In this paper, we combine the nonmonotone and adaptive techniques with trust region method for unconstrained minimization problems. We set a new ratio of the actual descent and predicted descent. Then, instead of the monotone sequence, the nonmonotone sequence of function values are employed. With the adaptive technique, the radius of trust region △k can be adjusted automatically to improve the efficiency of trust region methods. By means of the Bunch-Parlett factorization, we construct a method with indefinite dogleg path for solving the trust region subproblem which can handle the indefinite approximate Hessian Bk. The convergence properties of the algorithm are established. Finally, detailed numerical results are reported to show that our algorithm is efficient.     

First-principles study on the optical properties for CsI crystal with a pair of V_(Cs)~(1-)-V_I~(1+)

The electronic structures and optical properties of both the perfect CsI crystal and the crystal containing a pair of V_(Cs)~1-V_1~(1+) are calculated using CASTEP code with the lattice structure optimized.The calculated results indicate that the optical symmetry of the CsI crystal coincides with the lattice structure geometry of the CsI crystal.The absorption spectrum of the CsI crystal containing a pair of V_(Cs)~(1-)-V_1~(1+) also does not occur in the visible and near-ultraviolet range.It reveals tha...     

一种负高斯曲率的双三次Bézier曲面

负高斯曲率的曲面在建筑业、造船业及航空工业中都有广泛的应用。该文提出一种负高斯曲率双三次Ｂｅｚｉｅｒ曲面的构造方法，简单直观，几何意义明显。     

First-principles study on the optical properties for CsI crystal with a pair of VCs^1- - V1 ^1＋

The electronic structures and optical properties of both the perfect CsI crystal and the crystal containing a pair of VCs^1- -V1^1＋ are calculated using CASTEP code with the lattice structure optimized. The calculated results indicate that the optical symmetry of the CsI crystal coincides with the lattice structure geometry Vcs^1- - V1^1＋ of the CsI crystal. The absorption spectrum of the CsI crystal containing a pair of Vcs^1- - V1^1＋ also does not occur in the visible and near-ultraviolet range. It reveals that the existence of the pair of Vcs^1- - V1^1＋ in CsI crystal has no visible effects on the optical properties of the CsI crystal.     

中心性脾肾静脉断流联合分流术治疗门脉高压症疗效分析

门静脉高压症（portal hypertension，PHT）常导致食管胃底静脉曲张破裂大出血和肝性脑病等严重并发症，病死率高。PHT多需手术治疗，而且手术方式繁多，其术式的选择，直接影响患者的治疗效果和生活质量。断流术和分流术是广泛应用于临床的两种术式，其理论依据相悖，优缺点并存，正确合理的选择术式是提高PHT手术疗效的关键。断流术加分流术经过20余年的发展，现正被多数学者认可。近年来，我院采用分流加断流术治疗PHT患者30例，疗效较好，现报道如下。     

一维光子晶体带边激光器的阈值特性分析

采用麦克斯韦方程和速率方程相结合的模型和时域有限差分法,利用引入的有效增益分布因子概念研究了光子晶体中本征模的阈值特性。增益介质的大小以及在光子晶体中的位置直接影响光子晶体带边激光器的输出特性;有效增益分布因子描述了光子晶体中增益介质的空间分布特性。结果显示,带边本征模的激射阈值依赖于有效增益分布因子。不同的本征模具有不同的有效增益分布因子,那些有效增益分布因子较大的模式具有较低的阈值。通过调整增益介质的位置和长度,可以提高有效增益分布因子的值,从而降低激光器的阈值,这对于实现激光器的低阈值运行有指导作用。     

快速溶剂萃取-气相色谱法同时测定含脂羊毛中的28种有机氯拟除虫菊酯杀虫剂的残留量

建立了快速溶剂萃取-气相色谱法同时测定含脂羊毛中28种有机氯、拟除虫菊酯杀虫剂残留量的方法。在80 ℃、10.34 MPa条件下用正己烷饱和的乙腈快速提取样品,提取物经冷冻除脂、浓缩、固相萃取净化处理后直接用气相色谱分析。结果表明:16种有机氯杀虫剂在0.005～1.0 mg/L范围内,9种拟除虫菊酯杀虫剂及三氯杀螨醇、三氯杀螨砜在0.01～2.0 mg/L范围内,氟氯苯菊酯在0.02～4.0 mg/L范围内,其峰面积与质量浓度呈良好的线性关系。28种有机氯、拟除虫菊酯杀虫剂的平均回收率为67.2%～107.7%,相对标准偏差为2.6%～29.0%。结果表明：该方法具有操作简便、快速方便、灵敏度高等特点,完全可满足含脂羊毛中28种有机氯拟除虫菊酯杀虫剂残留量初筛检测的要求。     

捕食模型高精度参数的估计

研究了捕食者模型在多种观测值条件下的非线性微分方程组参数拟合问题.首先利用龙格-库塔法进行微分方程数值计算,通过首次积分项变形建立线性回归方程,进行最小二乘拟合;其次,考虑到实验数据包含随机误差的扰动,引进正规方程组对模型进行误差分析;最后针对时间变量也出现误差,采用拉依达准则筛选,然后提出了一种较为简单的参数分段动态估计算法.     

最优切割次序模型

本文研究了截断切割的最优切割次序模型。利用简单的伸缩变换,我们将r≠1的情况统一到的情况;我们讨论了切割方式的一些性质,如描述互换相邻切割对费用的影响的交换引理,同时在此基础上经严格证明给出了e=0时的一种十分简明的优化准则,每次选择切去长度最长的切割;在e>0的情况下,利用我们给出的引理及准则,我们将需考虑的不同切割方式数由最初的90种减少到不到20种.我们讨论了所建立模型的优缺点,同时也对另一种“加工费用最少者优先”的准则作了简单评估。