| Porous materials are kinds of materials which are the most extensively involved when human understand,use and transform nature.From the application of ancient earth and stone to the most promising development of gas storage materials in modern times,the interdisciplinary research field of porous materials has covered many subjects,such as chemistry,physics,mathematics,materials,energy sources, computer science and so on.This dissertation,where both theoretical calculations and applications of porous materials are invoved,developed six aspects basing on our previous study as following:(1)42 metal-organic frameworks(MOFs)materials were designed and their accessible surface,free volume and isometric heat of adsorption were calculated; methane and hydrogen adsorption in the MOFs were simulated with our GCMC program and relationship between the properties of MOFs and their adsorption amount of gas was correlated.The results show the adsorption abilities of MOFs mainly depend on isometric heat of adsorption,and little affected by other properties. Two new MOFs,IRMOF-4NO2 and IRMOF-14D2,of which linkers have more -NO2 and larger aromatic ring,were designed based on the analytical results.The adsorption amount of methane in two MOFs under 298 K and 3.5 MPa attains 209 and 260 cm3/cm3 respectively,each of which is higher than DOE's goal of methane storage(180 cm3/cm3).(2)The geometries,harmonic vibrational frequencies of all stationary points are calculated at MPW1K/6-31+G(d,p),BHandHLYP/6-31+G(d,p)and MPWB1K/ 6-31+G(d,p)level of DFT theory for three paths of hydrogen abstraction reactions from formaldehyde by ozone molecule both under and without water vapor condition. The thermal rate constants were evaluated based on the electronic structure and energy information from the HL//MPW1K/6-31+G(d,p)level of theory with the conventional transition state theory(TST)and canonical variational transition state theory(CVT)in the temperature range of 200-2500 K.The curves of TST and CVT without tunneling correction nearly overlap.The extended three-parameter Arrhenius expression fitted from the CVT/SCT rate constants of hydrogen abstraction in the temperature range 200-2500 K are k1CVT/SCT(T)=2.70×10-33T5.88e(-8131.7/T); k2CVT/SCT(T)=1.00×10-35T6.29e(-9198.4/T);k3CVT/SCT(T)=1.62×10-33T5.24e(-8985.2/T).The results show that hydrogen abstraction reactions(k1)will be more favorable at anhydrous condition.The works are significant to the method of formaldehyde waste gas treatment with ozone.(3)Adsorption isotherm of formaldehyde in MOF-5 at 298 K and 0～100 KPa was calculated by GCMC,and the result shows that the density based on volume of MOF-5 attains 0.4 g/cm3,which is closed to half of that of liquid formaldehyde.80% of adsorpted formaldehyde,however,will be desorpted from MOF-5 at 340 K, which illustrates that MOF-5 is a good formaldehyde adsorbent.These works theoretically provide a new method to treat waste gas containing formaldehyde.(4)Adsorption isotherms of argon and methane on the calcite {1(?)0} and {104} surface were calculated.The results show that only physical adsorption,monolayer adsorption under low pressure and multilayer adsorption under high pressure,was found on the two surfaces,and the {1(?)0} surface has stronger adsorption with argon and methane than that of the {104} surface.The Molecular dynamics calculation of water adsorption on the calcite {1(?)0} and {104} surfaces also shows the similar results,and adsorption heat on {1(?)0} surface and {104} surface is -38.93 Kcal/mol and -15.48 Kcal/mol,respectively.It also conveys that chemical adsorption may happen on the calcite surfaces for such high adsorption heat.The adsorption behavior of amylopectin on the two surfaces also was studied.It was found that amylopectin's shape was severely distorted for strong adsorption between amylopectin and the surfaces.Amylopectin is main component of sticky rice,so the simulation of amylopectin adsorption of the calcite surface will be very helpful to understand ancient mortars used in China,in which sticky rice was added.(5)The historical mortar samples were analyzed with FTIR,DSC-TG,SEM and XRD methods,and Starch-lodine test for the samples also were done.The results show that the mortar still contains some sticky rice and its degraded products. Specimens consolidated with modeling mortars exhibit good abilities in compression strength,surface hardness and water resistance tests.The high performance may own to the special microstructure which is controlled by sticky rice during carbonation of the mortar.The investigations could be helpful to understand the properties of ancient China mortar formulas and to choose proper usages of the mortars in loose historical stone consolidations.(6)The strength test results of earthen consolidated with Ionic Soil Stabilizer (ISS),potassium methylsilanolate(PMS)and high modulus potassium silicate(PS) solutions show that all of three consolidation agents can improve the strength of the specimens.In comparison with those of the low,medium and high density blank specimens,the compressive strength increases 36%,40%and 51%respectively after they were treated with PMS.The treated specimens can resist water corrosions. These indicate that PMS can be used as solidification agent for moist earth.In addition,PS also can consolidate moist earth after it is mixed into some of PMS, which can improve water resistance of PS.These works indicate that PMS will be helpful to solute the consolidation problem in moist earthen sites.In summary,topic of these works always focuses on fluid adsorption behavior of porous materials,and some nice results have been gained both in theoretical calculations and applications.These works,therefore,fulfill requirements of dissertation and the national projects.
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