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41.
Ming Guo Jue Wang Man Xiong Ronghui Wu Xuejuan Yang Jianzhong Zhou Minghui Li Jiajun Li 《大学化学》1986,35(12):237-246
In order to improve university laboratory teaching and practical education under the background of information technology, as well as overcome the difficulty for practical training, develop a virtual simulation experiment platform for rapid pyrolysis of natal materials and high-performance liquid chromatographic (HPLC) detection of its components. The experiment integrates the actual operation process of the plant to produce cleaved products by rapid pyrolysis of biomass with HPLC detection. The virtual experiment is divided into biomass sample pretreatment, rapid biomass pyrolysis, bio-oil extraction, and HPLC determination of complex components, making the biomass cleavage workshop "real" through simulation. This virtual simulation experiment fully integrates the utilization of biomass resources and basic chemistry courses (such as organic chemistry, instrumental analysis, chemical engineering principles, etc.), which are widely involved in agricultural and forestry majors with advantageous characteristics value. 相似文献
42.
Separation of metal ion complex, [(C(12)H(8)N(2))(3)Fe(2+)], with surfactant sodium dodecylphrate (DLS) complex from aqueous phase was carried out by solvent sublation, which obeys first-order kinetics. On the base of the complete transport mechanisms, the Langmuir adsorption, and the ion complex equilibrium in the aqueous phase, a mathematical model for the [(C(12)H(8)N(2))(3)Fe(2+)]-surfactant ion complex is obtained with the aid of the Mathematic 4.0 program, 4th Runge-Kutta method, and the Matlab programs. The effects of many parameters, such as K(a), K(l), K(ow), d(i), V(o), V(w), and Q(a), on solvent sublation are investigated. Furthermore, the simulation showed that the model is substantiated for experiments on the solvent sublation of the complex. 相似文献
43.
Xiao-Xian Chen Xiao-Yue Zhang De-Xuan Liu Rui-Kang Huang Sha-Sha Wang Li-Qun Xiong Wei-Xiong Zhang Xiao-Ming Chen 《Chemical science》2021,12(25):8713
The coexistence of multiferroic orders has attracted increasing attention for its potential applications in multiple-state memory, switches, and computing, but it is still challenging to design single-phase crystalline materials hosting multiferroic orders at above room temperature. By utilizing versatile ABX3-type perovskites as a structural model, we judiciously introduced a polar organic cation with easily changeable conformations into a tetrafluoroborate-based perovskite system, and successfully obtained an unprecedented molecular perovskite, (homopiperazine-1,4-diium)[K(BF4)3], hosting both ferroelectricity and ferroelasticity at above room temperature. By using the combined techniques of variable-temperature single-crystal X-ray structural analyses, differential scanning calorimetry, and dielectric, second harmonic generation, and piezoresponse force microscopy measurements, we demonstrated the domain structures for ferroelectric and ferroelastic orders, and furthermore disclosed how the delicate interplay between stepwise changed dynamics of organic cations and cooperative deformation of the inorganic framework induces ferroelectric and ferroelastic phase transitions at 311 K and 455 K, respectively. This instance, together with the underlying mechanism of ferroic transitions, provides important clues for designing advanced multiferroic materials based on organic–inorganic hybrid crystals.An unprecedented tetrafluoroborate-based perovskite reveals the coexistence of ferroelastic and ferroelectric transitions arising from delicate interplay between stepwise frozen organic cations and cooperative deformation of the framework. 相似文献
44.
PC/PBT共混体系的研究:Ⅰ.PC,PBT熔融共混时的酯交换反应 总被引:9,自引:0,他引:9
采用红外光谱、核磁共振等测试手段,系统地研究了PC、PBT熔融共混时的酯交换反应,发现PBT中残余的Ti催化剂会对酯交换反应起催化作用。通过加入能和Ti催化剂络合添加剂,可以控制酯交换程度,这为控制PC/PBT合金的性能提供了一个非常有效的方法。 相似文献
45.
Constituting the artificial carbon cycle,for example,through recycling CO2 and converting CH4 to value-added fuels and chemicals with solar energy,offers a sustainable future for humankind to tackle the global environmental issues and energy crisis.However,significant bottlenecks remain in such photocatalytic conversion,mainly related to the reaction activity and product selectivity.Herein,we share our efforts and systematic research progress on addressing the double bottlenecks for achieving solar-driven artificial carbon cycle,with specifically focusing on the photocatalytic CO2 and CH4 conversion.We further elucidate the common fundamentals behind various designed photocatalytic materials systems.Toward future development,we highlight the opportunities and challenges in the research field. 相似文献
46.
Xiong Ya Zou Xiao-Hua Wu Jian-Zhong Ji Liang-Nian Li Run-Hua Zhou Jian-Ying Yu Kai-Bei 《Transition Metal Chemistry》1999,24(3):263-267
A new polypyridyl ligand, MCP {MCP = 2-(3-chlorophenyl)imidazo[4,5-f]1,10-phenanthroline} and its ruthenium(II) complex, [Ru(bpy)2(MCP)](ClO4)2· 0.5MeCN (bpy = 2,2-bipyridine), have been synthesized and characterized. The structure of the complex was determined by single crystal X-ray diffraction techniques. The MCP ligand is essentially planar and the stacking interactions between the ligands were observed in the crystal. [Ru(bpy)2(MCP)]2+ can strongly bind to Calf thymus DNA through intercalation of MCP ligand. The Cl substitute group has no significant effect on the spectral properties and DNA-binding behaviour of the complex. 相似文献
47.
48.
介绍了NETWARE局域网的规划方法、实施步骤,并简述了其与INTERNET实现连接的几种方法。 相似文献
49.
智能材料与智能建筑结构 总被引:3,自引:0,他引:3
熊瑞生 《信阳师范学院学报(自然科学版)》1998,11(4):413-416,421
综述了智能材料与智能蛄构的研究与应用,着重论连了智能材料应用在建筑工程中彤成智能建筑结构,使建筑结构本身不仅具有承受荷戢的能力,而且还具有识别、分析、判断和驱动功能及自诊断、自适应和自修复功能。 相似文献
50.
1,6—二磷酸果糖制备研究:Ⅰ.菌种的筛选及培养条件 总被引:3,自引:2,他引:1
介绍了1,6-二磷酸果糖产生菌的筛选和最佳培养条件的确定,在所筛选的菌种中9518、9519号菌株均具较高的产1,6-二磷酸果糖酶系活力。其最佳培养条件为:培养温度28℃,pH6.5。 相似文献