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Simultaneous removing SO_2 and NO by a new system containing cobalt complex

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Journal of Environmental Sciences 2006年第3期18卷 567-571页

作者： ZHOU chun-qiong DEng xian-he PAN zhao-qun School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China

Absorption and catalytic oxidation of nitric oxide can be achieved by using cobalt（Ⅲ） ethylenediamine （Co（en）3^3＋. When simultaneous absorbing SO2 and NO, the precipitation of Co2（SO3）3 will be yielded and the NO removal will be decreased. A new catalyst system using Co（en）3^3＋ coupled with urea has been developed to simultaneous remove NO and SO2 in the flue gas. NO is absorbed and catalytically oxidized to nitrite and nitrate by Co（en）3^3＋. The dissolved oxygen in scrubbing solution from the feed stream acts as oxidant. Urea restrains the precipitation of Co2（SO3）3 by oxidizing SO3^2-to SO4^2- as COSO4 is more soluble in water. The experimental results proved that nearly all SO3^2- can be oxidized to SO4^2- and the high NO and SO2 removal could be obtained with the new system. The NO removal is influenced by gas flow rate, the concentration of Co（en）3^3＋ and urea in the absorption solution, the temperature of the scrubbing solution and the content of oxygen in the flue gas. The low gas flow rate is favorable to increase the NO removal. The experiments proved that the NO removal could be maintained at more than 95% by the system of 0.02 mol/L Co（en）3^3＋ and 1% urea at 50℃ with 10% O2 in the flue gas.

关键词： simultaneous removing SO2 and NO, Co(en)33+ urea SO32- oxidation

Dark Soliton of Polariton Condensates under Nonresonant PT-Symmetric Pumping

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Chinese Physics Letters 2020年第4期37卷 14-18页

作者： chun-Yu Jia zhao-xin Liang Department of Physics Zhejiang Normal UniversityJinhua 321004

A quantum system in complex potentials obeying parity-time(PT) symmetry could exhibit all real spectra,starting out in non-Hermitian quantum mechanics. The key physics behind a PT-symmetric system consists of the balanced gain and loss of the complex potential. We plan to include the nonequilibrium nature(i.e., the intrinsic kinds of gain and loss of a system) to a PT-symmetric many-body quantum system, with an emphasis on the combined effects of non-Hermitian due to nonequilibrium nature and PT symmetry in determining the properties of a system. To this end, we investigate the static and dynamical properties of a dark soliton of a polariton Bose–Einstein condensate under the PT-symmetric non-resonant pumping by solving the drivendissipative Gross–Pitaevskii equation both analytically and numerically. We derive the equation of motion for the center of mass of the dark soliton’s center analytically with the help of the Hamiltonian approach. The resulting equation captures how the combination of the open-dissipative character and PT-symmetry affects the properties of the dark soliton;i.e., the soliton relaxes by blending with the background at a finite time. Further numerical solutions are in excellent agreement with the analytical results.

关键词： soliton symmetry quantum

Modeling and Motion Simulation for A Flying-Wing Underwater Glider with A Symmetrical Airfoil

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China Ocean Engineering 2019年第3期33卷 322-332页

作者： zhao Liang WAng Peng SUN chun-ya SOng Bao-wei School of Marine Science and Technology Northwestern Polytechnical University Xi’an 710072 China The 719 Research Institute of CSIC Wuhan 430064 China

The flying-wing underwater glider (UG), shaped as a blended wing body, is a new type of underwater vehicle and still requires further research. The shape layout and the configuration of the internal actuators of the flying-wing UG are different from those of "legacy gliders" which have revolving bodies, and these two factors strongly affect the dynamic performance of the vehicle. Considering these differences, we propose a new configuration of the internal actuators for the flying-wing UG and treat the flying-wing UG as a multi-body system when establishing its dynamic model. In this paper, a detailed dynamic model is presented using the Newton-Euler method for the flying-wing UG. Based on the full dynamic model, the effect of the internal actuators on the steady gliding motion of vehicle is studied theoretically, and the relationship between the state parameters of the steady gliding motion and the controlled variables is obtained by solving a set of equilibrium equations. Finally, the behaviors of two classical motion modes of the glider are analyzed based on the simulation. The simulation results demonstrate that the motion performance of the proposed flying-wing UG is satisfactory.

关键词： flying-wing underwater glider blended-wing-body dynamic modeling motion simulation steady motion

MODELIng ON DYNAMIC PROCESS OF MEMBRANE FOULIng DURIng FINITE CROSSFLOW ULTRAFILTRATION IN CHARGED SYSTEM

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Journal of Hydrodynamics 2006年第2期18卷 206-210页

作者： LUO Ming-Liang PU chun-sheng zhao Jian-qing College of Petroleum Engineering China University of Petroleum （East China） Dongying 257061 China College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

Flux decline during finite crossflow Ultrafiltration（UF） in charged system was investigated by perceiving membrane fouling as a dynamic process from non-equilibrium to equilibrium. Under the influence of the boundary condition at the initial section and cross flow, the equilibrium is first reached at the initial section of the crossflow filter and the front of the equilibrium region progresses with time toward the end of the filter. A mathematic model was developed to describe this dynamic process of membrane fouling in a charged system. With the model, the time-dependent flux and the time required to reach the steady state in a crossflow filtration can be easily determined. The fouling process under different conditions is simulated as illustrated with a demonstration of the newly developed model. The resulls of simulation show that there are jumps in the local flux at the front of the equilibrium region and the electrokinetic properties of charged UF system have a very substantial influence on the separation performance of membrane.

关键词： fouling dynamics flux decline,Ultrafiltration(UF) charged system modeling

Ground experiments and performance evaluation of the Low-Frequency Radio Spectrometer onboard the lander of Chang’e-4 mission

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Research in Astronomy and Astrophysics 2021年第5期21卷 139-146页

作者： xin-Ying Zhu Yan Su Yi-Cai Ji Hong-Bo Zhang Bo zhao Jun-duo Li Shun Dai xi-Ping Xue chun-Lai Li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Institute of Electronics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The Low-Frequency Radio Spectrometer(LFRS)is a scientific payload onboard the Chang’e-4 lunar lander launched in December *** LFRS provides in-situ measurements of the low-frequency radio phenomena on the far-side of theMoon for the first time in human *** evaluate the performance of the LFRS,a series of ground experiments are conducted using an engineering model of the *** is not easy to perform the experiments because the Electro Magnetic Interference(EMI)from the Chang’e-4 lunar lander itself and the environment is very *** results after EMI mitigation show that the sensitivity of the LFRS may be 10^(−18)W m^(−2)Hz^(−1).

关键词： Moon:far-side space vehicles:instruments techniques:spectroscopic

Stable metal-organic frameworks with high catalytic performance in the cycloaddition of CO_2 with aziridines

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Science China Chemistry 2019年第5期62卷 622-628页

作者： xiao-Min Kang Ying Shi chun-Shuai Cao Bin zhao College of Chemistry and Key Laboratory of Advanced Energy Material Chemistry Nankai University

Based on the mixed ligands XN(4′-(4-pyridine)4,2′:2′,4′′-terpyridine) and isophthalic acid(IPA), three new metal-organic frameworks(MOFs) {[M_2(XN)_2(IPA)_2]·2 H_2O}_n(M=Co(1), Mn(2), Ni(3)) were assembled and structurally characterized,presenting 3 D pillar-chain feature structures. Stability measurements demonstrate that these compounds possess high thermostability and can endure different organic solvents as well as various acid/base solutions with pH range of 1 to 14. Importantly,compounds 1–3 can serve as high-efficiency catalysts for the transformation of CO_2 and aziridines to form high-value oxazolidinones under mild conditions, exhibiting excellent cyclicity at least five times.

关键词： MOFs stability catalysis oxazolidinones CO2 conversion

Structure Evolution Mechanism of Poly(acrylonitrile/itaconic acid/acrylamide) during Thermal Oxidative Stabilization Process

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Chinese Journal of Polymer Science 2017年第8期35卷 1020-1034页

作者： zhao-po zeng ze-chun shao 肖茹 yong-gen lu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials & College of Materials Science and Engineering Donghua University Shanghai 201620 China

Polyacrylonitrile （PAN） polymers with different compositions were prepared by an efficient aqueous free-radical polymerization technique. Thermal properties of polyacrylonitrile homopolymer （PAN）, poly（acrylonitrile/itaconic acid） [P（AN/IA）] and poly（acrylonitrile/itaconic acid/acrylamide） [P（AN/IA/AM）] were studied by Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and thermogravimetry in detail. It was found that AM had the ability to initiate and accelerate thermal oxidative stabilization process, which was confirmed by the lower initiation temperature and broader exothermic peak in P（AN/IA/AM） as compared with that in P（AN/IA） and PAN. The intensity of heat releasing during the thermal treatment was relaxed due to the presence of two separated exothermic peaks. Accompanied by DSC analysis and calculation of the apparent activation energy of cyclization reaction, two peaks were assigned to the ionic and free radical induction mechanisms, respectively. The higher rate constant in P（AN/IA/AM） indicated that the ionic mechanism actually had a kinetic advantage at promoting thermal stability over the free radical mechanism. This study clearly show that the synthesized P（AN/IA/AM） terpolymers possess larger room to adjust manufacture parameters to fabricate high performance of PAN-based carbon fibers.

关键词： PAN terpolymers Structural evolution Thermal oxidative stabilization Thermal analysis Kinetics

A water-stable metal-organic framework： serving as a chemical sensor of PO43– and a catalyst for CO2 conversion

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Science China Chemistry 2017年第10期60卷 1328-1333页

作者： Bin Zhai Hang Xu Zhong-Yi Li chun-Shuai Cao Bin zhao College of Chemistry and Chemical Engineering Shangqiu Normal University Shangqiu 476000 China Key Laboratory of Advanced Energy Material Chemistry Department of Chemistry Nankai University Tianjin 300071 China Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300071 China

A new 2D Eu-BTB framework(1) with stratified gridding structure of about 14.6×16.9was synthesized and *** 1 displays excellent water stability with the pH 2–12. The luminescent investigations suggest that 1 could represent a chemical sensor of PO43. with high sensitivity and selectivity. Importantly, 1 as a sensor of PO_4^(3-) can be reused at least five *** the other hand, the catalytic investigations of 1 were carried out, indicating that 1 could be demonstrated as a recyclable catalyst for CO_2 conversion with epoxides.

关键词： MOFs water and pH stability luminescent detection CO_2 conversion

Analysis of Water Resources Supply and Demand and Security of Water Resources Development in Irrigation Regions of the Middle Reaches of the Heihe River Basin, Northwest China

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Agricultural Sciences in China 2006年第2期5卷 130-140页

作者： JI xi-bin KAng Er-si CHEN Ren-sheng zhao Wen-zhi XlAO Sheng-chun JIN Bo-wen Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 P.R.China Linze Inland River Basin Comprehensive Research Station Chinese Ecosystem Network Research Linze 734200 P.R.China

Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year （2003）, the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system.

关键词： middle reaches of Heihe River irrigation region water resources supply and demand balance evaluation of the security of water resources