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161.
方绪华 《福州大学学报(自然科学版)》1998,(5):65-68
讨论全站仪配合PC-E500袖珍计算机使用统一坐标系统进行高等级公路施工测量,重点分析高等级公路施工阶段,控制点、细部点的坐标计算方法和测设方法. 相似文献
162.
Taking a typical local and industry-orientated applied chemistry major as an example with focusing on the major changes in the form and content of the petrochemical industry, the way to reform the core curriculum system and teaching contents is presented. Based on the changing tendency of refinement of the petrochemical industry, a complete curriculum system with distinctive industry characteristics is set up according to the principles of the emerging engineering education (3E) with several reasonable suggestions. A new model for the construction of a 3E major in chemistry-related majors is suggested. It is a good reference for the construction of curriculum systems for other local and industry-orientated colleges who want to make 3E reform. 相似文献
163.
The micro construction of poly(epsilon-caprolactone) (PCL) and poly(L-lactic acid) (PLLA) blend films fabricated by solution casting under microwave irradiation was investigated by selective enzymatic degradation and scanning electron microscopy (SEM). The results were totally different from the blends obtained by conventional methods. The blend was more homogeneous and the PCL continuous phase more compact as no spherulites and tiny zone separation were observed from the film surface and no PCL network was observed inside the film, and the degradation of a PCL plank by Pseudomonas lipase was significantly retarded. The distributed PLLA micro spheres were enlarged and amorphous. The thermal behavior of the blend by microwave heating revealed that PCL and PLLA underwent a melting process, which induced the variations of the PCL phase and PLLA spheres. The weight loss caused by degradation of the PCL/PLLA blend obtained by conventional methods (B50c) is greater than that of the blend obtained by microwave methods (B50m), which reflects the change in morphology from a loose PCL network (B50c) to a dense PCL plank (B50m). 相似文献
164.
《中国化学快报》2020,31(4):1030-1033
Herein,a simple yet efficient hydrothermal strategy is developed to in-situ convert multi-layered niobium-based MXene(Nb_2 CT_x) to hierarchical Nb2 CTx/Nb_2O_5 composite.In the hybrid,the Nb_2O_5 nanorods are well dispersed in and/or on the Nb_2 CTx.Thanks to the synergetic contributions from the high capacity of Nb_2O_5 and superb electrical conductivity of the two-dimensional Nb_2 CT_x itself,the resultant Nb_2 CTx/Nb_2O_5 hybrid exhibits excellent rate behaviors and stable long-term cycling behaviors,when evaluated as anodes for Li-ion batteries. 相似文献
165.
Bei-sheng Kang Mao-chun Hong Ting-bin Wen Han-qin Liu Jia-xi Lu 《Journal of Cluster Science》1995,6(3):379-401
Simple fragments of transition metal 1,2-bidentate thiolates, the so-called building blocks of the general compositions ML3, ML2, ML, M(O)L2, ML2L, MLL, etc. have been proposed to constitute the di-, tri- and tetranuclear complexes concerned in this review. Structureal regularities and characteristics have been discussed and summarized according to the thiolato ligands edt and pdt, bdt and tdt, mp, and mpo, and mpp, respectively.Abbreviations H2mpo
o-mercaptophenol
- Hmpo
2-mercaptopyridine-N-oxide
- R2dtc
N,N-dialkyldithiocarbamate
- Haet
2-aminoethanethiol
- H2bdt
o-benzenedithiol
- H2pdt
1,2-propanedithiol
- H2tdt
toluene-3,4-dithiol
- Hmpp-mppH
bis-(3-hydroxy-2-pyridyl)disulfide
- Hmp-mpH
bis-(2-oxyphenyl)disulfide
- H2edt
1,2-ethanedithiol
- dppe
1,2-bis(diphenylphosphino)ethane
- H2tedt
3,4,5,6-tetrachlorobenzene-1,2-dithiol
- H2tpdt
3-thiapentane-1,5-dithiol
- H2mnt
maleonitriledithiol
- Him
imidazole
- Bz
benzyl
- py
pyridine 相似文献
166.
167.
为深入了解地方性师范院校化学师范生知识建构习惯和水平,探讨他们在大学专业基础课程中的学习历程,以物理化学课程中以“融合科学读写特色”的“热化学”学案作为研究载体,研究对象在学案引导下开展自学活动,并在阅读教材和文献基础上进行科学写作。采用量表工具针对大学生自学效果和反思活动进行评价,并采用SOLO分类评价科学写作作品,采用KWL工具评价学生的科学阅读收获。结果发现研究对象学习动机不强,不擅长在新的学科知识学习中联系已有专业课程知识,基于文本学习的建构活动水平极低,可能是因为他们在应试背景下的基础知识并未形成体系,先修课程中并未培养元认知学习策略。 相似文献
168.
The graphical unitary group approach has been applied in an efficient implementation of a general multireference configuration interaction (MRCI) method for use with small active molecular orbital spaces in a semiempirical framework. Gradients can be computed analytically for molecular orbitals from a closed-shell or a half-electron open-shell Hartree-Fock calculation. CPU times for single point energy and gradient calculations are reported. The code allows MRCI geometry optimizations of large molecules, as illustrated for the singlet ground state and the four lowest triplet states of fullerene C(76). 相似文献
169.
自由电子激光光导的数值模拟与分析 总被引:1,自引:0,他引:1
从一维自由电子激光理论出发,唯象地考虑衍射效应,计算和分析了光导效应的特点和规律;针对曙光一号装置的自由电子激光参数,利用二维理论对光场剖面、填充因子、光场半径等进行了数值模拟;根据计算结果分析和讨论了影响光导的因素和实验条件。 相似文献
170.
总结了1998年以来青海省水利建设管理中取得的成绩,指出了水利建设管理中存在的问题,并对今后的发展方向进行了探讨。 相似文献