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With the rapid development of science and technology, knowledge update is accelerating, which puts forward higher requirements for teachers and students in Colleges and universities, and needs to grasp the latest development trends of curriculum knowledge related fields faster, more comprehensive and more accurate. Many schools have digitized their educational resources. However, the traditional sharing of educational resources lacks a unified knowledge representation structure, which makes the sharing and reuse of learning resources unsatisfactory. Curriculum is the core of school knowledge teaching. It evaluates the curriculum system and discipline system in order to achieve certain teaching objectives. Curriculum knowledge includes explicit knowledge and tacit knowledge.Knowledge map is a kind of model which can describe knowledge in semantic and knowledge level. Its purpose is to acquire, organize and present knowledge in a general and intuitive way, to search and match knowledge quickly, so as to improve the utilization of knowledge by learners and knowledge workers. Curriculum knowledge has obvious ontology characteristics, and there are many inconveniences and shortcomings in the presentation of traditional knowledge map. Using ontology technology to construct curriculum knowledge map can not only reflect the relationship between knowledge modules, but also realize the mining and representation of more knowledge relations and types such as tacit knowledge to a certain extent.

Coordination of supramolecular assemblies was investigated by reacting a series of lanthanide cations (Ln3+) with an inverted cucurbituril (iQ[6]) in the presence of tetrachloride zincate anion [ZnCl4]2−, as an structure directing agent in aqueous HCl (3.0 mol/L). Single crystal X-ray diffraction analysis revealed that the coordination of iQ[6] with Ln3+ gave rise to different interaction products and isomorphous groups with increasing atomic number. The interaction of iQ[6] with La3+ and Ce3+ immediately yielded precipitations and single crystal solids containing Pr3+ and Nd3+. No solids resulted from coordination of iQ[6] with Sm3+ and Eu3+, whereas single crystals solids were obtained from coordination of iQ[6] with heavy Ln3+, such as Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+ and Lu3+. Such coordination characteristics may offer a strategy for isolating a series of Ln3+ cations in patches.

Single-molecule detection can reveal time trajectories and reaction pathways of individual intermediates/transition states in chemical reactions and biological processes, which is of fundamental importance to elucidate their intrinsic mechanisms. We present a reliable, label-free single-molecule approach that allows us to directly explore the dynamic process of basic chemical reactions at the single-event level by using stable graphene-molecule single-molecule junctions. These junctions are constructed by covalently connecting a single molecule with a 9-fluorenone center to nanogapped graphene electrodes. For the first time, real-time single-molecule electrical measurements unambiguously show reproducible large-amplitude two-level fluctuations that are highly dependent on solvent environments in a nucleophilic addition reaction of hydroxylamine to a carbonyl group. Both theoretical simulations and ensemble experiments prove that this observation originates from the reversible transition between the reactant and a new intermediate state within a time scale of a few microseconds. These investigations open up a new route that is able to be immediately applied to probe fast single-molecule physics or biophysics with high time resolution, making an important contribution to broad fields beyond reaction chemistry.

Coordination in supramolecular assemblies in aqueous HCl solutions was investigated by reacting alkaline-earth cations (AE2+) and inverted cucurbit[6]uril (iQ[6]) in the presence of the structure-directing agent, tetrachloride zincate ion. Single-crystal X-ray diffraction analysis revealed that the iQ[6]–Mg2+–[ZnCl4]2––HCl interaction system yielded a supramolecular assembly of iQ[6] and [ZnCl4]2– without forming coordination complexes of Mg2+ or Zn2+ with iQ[6]. In contrast, interaction of Ca2+ or Sr2+ with iQ[6] in the presence of [ZnCl4]2– gave rise to linear coordination polymers, which formed a honeycomb-like framework in which the linear polymers occupy cells of the framework. The iQ[6]–Ba2+–[ZnCl4]2––HCl interaction system immediately produced precipitates, thus preventing isolation of single crystals under similar synthetic conditions.

Dual-functional nanoparticles, with the property of aggregation-induced emission and the capability of reactive oxygen species, were used to achieve passive/active targeting of tumor. Good contrast in in vivo imaging and obvious therapeutic efficiency were realized with a low dose of AIE nanoparticles as well as a low power density of light, resulting in negligible side effects., Comment: 30 pages, 7 figures

Based on the analysis of the load curves taken from more than 300 beam pumping motors (BPMs) in China, a novel power-off control method for BPMs is developed, which enables the oil pumps to work continuously relying solely on the potential energy released during the power-off interval. The main advantages of this are: (1) variation of load curves is monitored by micro-computer in real time, and the control parameters, such as power-off moment and duration, are adjusted automatically; and (2) rapid soft re-switching technology, which is realized by SCR controlled by micro-computer, is developed for re-switching when the power source is needed during the power-off interval, by which the inrushing current is less than the rated one. To further broaden the applications for various beam pumping units, the multifunctional energy-saving device (MESD) is also developed, which uniquely integrates power-off control, wye-delta automatic conversion and auto-reactive power compensation technologies. During the past five years, more than 600 sets of MESDs had been put into use in Daqing oil field and the power saving ratio is in the range of 10-25%.

The spectra of volatiles of fresh garlic, Chinese chive and scallion plants were successfully recorded by headspace combined with surface-enhanced Raman scattering using the portable Raman spectrometer. For garlic: high intensity bands are present in 1622, 1397, 1287, 1182, 711, 569, 461 cm-1 and low intensity bands are present in 1017, 979, 918, 307 cm-1. For Chinese chives: the high intensity band is present in 672 cm-1 and low intensity bands are present in 1618, 1396, 1289, 1185, 575, 412, 274 cm-1 . For scallion high intensity bands are present in 699, 1023 cm-1 and low intensity bands are present in 369, 887, 1084, 1314 cm-1 . The main volatiles of fresh garlic, Chinese chive and scallion are diallyl disulfide, allyl methyl sulfide and 1-propanethiol respectively. As the bulk concentration changes, different conformers are absorbed on silver.