Three silicon and nitrogen-centered cyanate monomers tetrakis(4-cyanatophenyl)silane, tetrakis(4-cyanatobiphenyl)silane, and tris(4-cyanatobiphenyl)amine were designed and synthesized, which were then polymerized via thermal cyclotrimerization reaction to create highly porous cyanate resin networks with systematically varied nodes and linking struts. The chemical structures of monomers and polymers were confirmed by 1 H NMR, FTIR, solid-state 13 C CP/MAS NMR spectra, and elemental analysis. The products are amorphous with 5% weight-loss temperatures over 428 °C. The results based on N 2 and CO 2 adsorption isotherms show that the pores in these polymers mainly locate in the microporous region, and the BET surface areas are up to 960 m 2 g −1 , which is the highest value for the porous cyanate resin reported to date. The nitrogen-and oxygen-rich characteristics of cyanate resins lead to the networks strong affinity for CO 2 and thereby high CO 2 adsorption capacity of 11.1 wt % at 273 K and 1.0 bar. The adsorption behaviors of H 2 , CO 2 , benzene, n-hexane, and water vapors were investigated by correlating with the chemical composition and porosity parameters of the networks as well as the physicochemical nature of adsorbates.

Tetraphenyladamantane-based microporous polyimide was synthesized. It can uptake 14.6 wt% CO2 at 273 K and 1 bar, 99.2 wt% benzene and 59.7 wt% cyclohexane at 298 K and 0.9 bar, exhibiting potential applications in gas storage and recovery of organic pollutants.

A new microporous polyimide network (PI-ADNT) is synthesized from 1,3,5,7-tetrakis(4-aminophenyl)adamantane and naphthalene-1,4,5,8-tetracarboxylic dianhydride. Subsequently, PI-ADNT is nitrated in fuming nitric acid with different nitration time to produce three nitro-decorated porous polyimides (PI-NO2s). Their chemical structures and nitration degrees are characterized by FTIR, solid-state 13C CP/MAS NMR spectra and element analysis. The interesting evolution of porous morphology and porosity of PI-NO2s with nitration time is investigated in detail. The results show that PI-ADNT has the BET surface area of 774 m2 g–1 with microporous size centering at 0.75 nm. After nitration-modifications, PI-NO2s display decreased surface area but remarkably increased CO2 uptake up to 4.03 mmol g–1, which is superior to most of porous polymers reported in the literature. Moreover, the CO2 adsorption selectivites over CH4 and N2 in PI-NO2s are also significantly improved in comparison with PI-ADNT. The CO2 adsorption/separation properties of PI-ADNT and its nitrated products are studied and explained in terms of the variations of porous structure and chemical composition as well as the interaction parameters between CO2 molecule and polymer skeleton such as Henry’s constant, first virial coefficient, and enthalpy of adsorption.

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This report presents the synthesis of a tetraphenyladamantane-based microporous polycyanurate network with a BET surface area of 843 m(2) g(-1) and a pore size of 7.8 Å. It uptakes 98.0 wt% benzene (298 K, P/P0 = 0.9), 1.49 wt% H2 (77 K/1 bar) and 12.8 wt% CO2 (273 K/1 bar) with CO2/N2 selectivity of up to 112.

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a b s t r a c tHeat pump technology fully shows the principle of energy recycling in terms of Heating, Ventilating and Air Conditioning (HVAC). It avoids unipolarity of energy using in the conventional HVAC system. Heat pumps use high-grade energy as a driving energy, recovering and upgrading low-grade energy for avail, like a pump. Because heat source used in HVAC usually is low temperature heat, heat pump systems adopted in HVAC will help improve heating performance coefficient. Therefore, HVAC is one of ideal users of heat pump applications, and thus high-grade energy used in HVAC can be replaced with a large number of low-temperature renewable energy. Through the heat pump technology, natural low-grade energy stored in the soil, water, air or waste heat from variant industries and daily lives, is supplied for building cooling/heating and hot water serving. Therefore, vast applications and developments of heat pump technology are presented in HVAC in China, and some progresses are achieved in the system innovation, experimental research, product development and engineering application, etc. This paper reviews the progress of researches, applications and development in the field of heat pumps for building cooling/heating in China since the 21st century.

The electrochemical advanced oxidation process (EAOP) has gained popularity in the field of water purification. During the EAOP, it is in the boundary layer of the anode–solution interface that organic pollutants are oxidized by hydroxyl radicals (•OH) produced from water oxidation. Applying current to an anode dissipates heat to the surroundings according to Joule’s law, leading to an interfacial temperature that is much higher than that of the bulk solution, which is known as the “interfacial Joule heating” (IJH) effect. The modeling and experimental results show that the IJH effect had an inevitable consequence for the activity of •OH, rate constants, and mass transport within the boundary layer. The interfacial temperature could be increased from 25 to 70.2 °C, a value mostly doubling that of the bulk solution (33.6 °C) at the end of a 120 min electrolysis (10 mA cm–2). Correspondingly, the •OH concentration available for oxidation of organic pollutants was much lower than that calculated at a constant temperature of 25 °C probably due to H2O2 formation via •OH dimerization. The enhanced •OH diffusion resulting from strengthened molecular thermodynamic movement and decreased kinematic viscosity of the solution also drove •OH to move far from the anode surface and thus extended the maximum thickness of the boundary layer. The oxidation rate was positively correlated to the interfacial temperature, the activation energy, and the number of activated molecules, indicated by a 1.57–2.28-fold increase depending on the target organic compounds. The finding of the IJH effect prompts a re-examination of the literature based on a realistic rather than a constant temperature (e.g., 20–30 °C), the case reflected in a number of prior studies that does not exist virtually, and reconsideration of behaviors that can be attributed to the change in temperature during EAOP.