The struetural effect of the conjugative system(C)with carbonyl-imino bridges has been studied.The results show that:In the conjugated system(C),there is no electronic absorption peak attributable to the whole system,...The struetural effect of the conjugative system(C)with carbonyl-imino bridges has been studied.The results show that:In the conjugated system(C),there is no electronic absorption peak attributable to the whole system,but there are three π-π* bands each nt which displays chacactecistics of its own independently.These indicate that the two bridges-carbonyl-and-imino-can block the tlanSmlSSion of the conjngative polarization of the whole system,so as to form three segments,this is verified by means of chemical synthesis and degradation.展开更多
A novel Fe/amine modified chitosan composite(Fe/N-CS) was facilely synthesized and showed higher affinity to both Zn(Ⅱ) and cefazolin(CEF) than its precursors.Synergistic co-adsorption of them by Fe/NCS was observed ...A novel Fe/amine modified chitosan composite(Fe/N-CS) was facilely synthesized and showed higher affinity to both Zn(Ⅱ) and cefazolin(CEF) than its precursors.Synergistic co-adsorption of them by Fe/NCS was observed in varied conditions.The adsorption amount maximally increased by 100.1% for Zn and68.2% for CEF in bi-solute systems.The initial adsorption rate of Zn(Ⅱ) also improved with CEF.The increasing temperature facilitated coadsorption.The results of the preloading tests,FTIR/XPS characterizations and DFT calculations suggested that(1) both polyamines and Fe sites participated in the adsorption of Zn(Ⅱ) and CEF,(2) Zn(Ⅱ) could serve as a new efficient site for CEF,forming [amineZn-CEF]/[FeOH-Zn-CEF] ternary complexes,and(3) the co-presence of CEF shielded the electrostatic repulsion between protonated amines and Zn(Ⅱ),contributing to the enhancement of Zn(Ⅱ) adsorption.Further,the ion strength exerted positive and negative influences on the adsorption of Zn(Ⅱ) and CEF,respectively.Additionally,CEF and Zn(Ⅱ) were successively recovered by 0.1 mol/L NaOH followed by2 mmol/L HCl.Fe/N-CS could be stably reused five times.The findings imply that Fe/N-CS is promising for the highly efficient co-removal of concurrent heavy metals and antibiotics.展开更多
In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete（PC） curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote r...In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete（PC） curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote real-time temperature collection system to collect temperature data on site, and further uses the software ANSYS for analysis. Based on the comparisons between the measured data and the simulation results, the following conclusions can be drawn： 1 Our temperature monitoring system is reliable; 2 The corresponding measured data of the web plate and flange plate exposed to the sun, vary more severely than that at other positions, so these plates need higher standard design and construction requirements; 3 In the cold wave where still is sunshine, the box girder temperature effect behaves as sine-like curve.展开更多
The most common state of surface soil is unsaturated.Changes in water content will substantially impact its strength,leading to geological and engineering catastrophes.This paper used LIGGGHTS software to simulate the...The most common state of surface soil is unsaturated.Changes in water content will substantially impact its strength,leading to geological and engineering catastrophes.This paper used LIGGGHTS software to simulate the water bridge effect of unsaturated granular materials with constant water content and verify the rationality of the simplification of the stress-force-fabric(SFF)relationship.The results showed that the capillary force was not isotropic,which was different from the previous study,thus it cannot be overlooked in the simplification of the SFF relationship.Moreover,the influence of water content on the macroscopic mechanical behavior of unsaturated granular materials was interpreted through the evolutions of coordination number,interparticle force,fabric and force anisotropy,and other microscopic parameters.Compared to the literature,we found that different water bridge models would not change the characteristics of the solid skeleton.展开更多
文摘The struetural effect of the conjugative system(C)with carbonyl-imino bridges has been studied.The results show that:In the conjugated system(C),there is no electronic absorption peak attributable to the whole system,but there are three π-π* bands each nt which displays chacactecistics of its own independently.These indicate that the two bridges-carbonyl-and-imino-can block the tlanSmlSSion of the conjngative polarization of the whole system,so as to form three segments,this is verified by means of chemical synthesis and degradation.
基金supported by the National Natural Science Foundation of China(No.51708281)Natural Science Foundation of Jiangsu Province,China(No.BK20170647)State Key Laboratory of Pollution Control and Resource Reuse Open Funding Project(No. PCRRF18022)
文摘A novel Fe/amine modified chitosan composite(Fe/N-CS) was facilely synthesized and showed higher affinity to both Zn(Ⅱ) and cefazolin(CEF) than its precursors.Synergistic co-adsorption of them by Fe/NCS was observed in varied conditions.The adsorption amount maximally increased by 100.1% for Zn and68.2% for CEF in bi-solute systems.The initial adsorption rate of Zn(Ⅱ) also improved with CEF.The increasing temperature facilitated coadsorption.The results of the preloading tests,FTIR/XPS characterizations and DFT calculations suggested that(1) both polyamines and Fe sites participated in the adsorption of Zn(Ⅱ) and CEF,(2) Zn(Ⅱ) could serve as a new efficient site for CEF,forming [amineZn-CEF]/[FeOH-Zn-CEF] ternary complexes,and(3) the co-presence of CEF shielded the electrostatic repulsion between protonated amines and Zn(Ⅱ),contributing to the enhancement of Zn(Ⅱ) adsorption.Further,the ion strength exerted positive and negative influences on the adsorption of Zn(Ⅱ) and CEF,respectively.Additionally,CEF and Zn(Ⅱ) were successively recovered by 0.1 mol/L NaOH followed by2 mmol/L HCl.Fe/N-CS could be stably reused five times.The findings imply that Fe/N-CS is promising for the highly efficient co-removal of concurrent heavy metals and antibiotics.
基金Supported by the China Postdoctoral Science Foundation(2013M531560)the Technology Innovation Plan in Traffic of Shandong Province(2012A15)the Science&Technology Development Projects of Shandong Province(2014GSF120015)
文摘In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete（PC） curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote real-time temperature collection system to collect temperature data on site, and further uses the software ANSYS for analysis. Based on the comparisons between the measured data and the simulation results, the following conclusions can be drawn： 1 Our temperature monitoring system is reliable; 2 The corresponding measured data of the web plate and flange plate exposed to the sun, vary more severely than that at other positions, so these plates need higher standard design and construction requirements; 3 In the cold wave where still is sunshine, the box girder temperature effect behaves as sine-like curve.
基金This work was supported by the National Natural Science Foundation of China(grant numbers:51909139,52011530458).
文摘The most common state of surface soil is unsaturated.Changes in water content will substantially impact its strength,leading to geological and engineering catastrophes.This paper used LIGGGHTS software to simulate the water bridge effect of unsaturated granular materials with constant water content and verify the rationality of the simplification of the stress-force-fabric(SFF)relationship.The results showed that the capillary force was not isotropic,which was different from the previous study,thus it cannot be overlooked in the simplification of the SFF relationship.Moreover,the influence of water content on the macroscopic mechanical behavior of unsaturated granular materials was interpreted through the evolutions of coordination number,interparticle force,fabric and force anisotropy,and other microscopic parameters.Compared to the literature,we found that different water bridge models would not change the characteristics of the solid skeleton.
