SrTiO_3 nano-crystal samples with floccule or flake crystal morphology,which were indexed as a perovskite-type crystal structure based on the results of XRD and TEM,were successfully prepared by one-step liquid reacti...SrTiO_3 nano-crystal samples with floccule or flake crystal morphology,which were indexed as a perovskite-type crystal structure based on the results of XRD and TEM,were successfully prepared by one-step liquid reaction method.And the growth mechanism of the SrTiO_3 nano-crystals under the liquid condition with/without adding the surface active agent was investigated.It was found that adding the surface active agent contributes to the processing in which the ions gathering bodies transit to a more stable phase through the chemical reaction and form the flake SrTiO_3 nano-crystals.展开更多
New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable...New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable energy source for heating and electricity generation due to its high combustion value.Currently,natural gas accounts for a large portion of electricity generation and chemical feedstock in manufacturing plastics and other commercially important organic chemicals.In the near future,natural gas will be widely used as a fuel for vehicles.Therefore,a practical storage device for its storage and transportation is very beneficial to the deployment of natural gas as an energy source for new technologies.In this tutorial review,biomaterials-based carbon monoliths(CMs),one kind of carbonaceous material,was reviewed as an adsorbent for natural gas(methane)adsorption and storage.展开更多
Objective:To investigate the efficacy of 17 ethnomedicinal plants belonging to Apocynaceae family used in combination with 16 conventional antibiotics against non-multidrug resistant-,multidrug resistant(MDR)-.and ext...Objective:To investigate the efficacy of 17 ethnomedicinal plants belonging to Apocynaceae family used in combination with 16 conventional antibiotics against non-multidrug resistant-,multidrug resistant(MDR)-.and extensive drug resistant(XDR) Acinetobacter baumannii(A.haumannii).Methods:Antibacterial activity and resistance modifying ability of 272combinations were determined by growth inhibition assays and further confirmed by time-kill assay.Results:Among the combinations of the antibiotics with Apocynaceae ethanol extracts on this pathogen,15(5%) had synergistic effects,23(8%) had partial synergistic effects and 234(86%) had no effects.Synergistic activity was observed mostly when the Apocynaceae extracts were combined with rifampicin or cefazolin.Interestingly.10 out of 17 combinations between the extracts and rifampicin displayed synergistic or partial synergistic behaviors.Holarrhena antidysenterica extract was additionally tested to restore rifampicin activity against clinical isolates of MDR and XDR A.haumannii.With respect to total or partial synergy,70%was XDR A.haumannii isolates and 66%was MDR A.haumannii isolates.Conclusions:Holarrhena antidysenterica extract clearly demonstrated the ability to restore rifampicin activity against both A.haumannii ATCC19606 and clinically isolated A.haumannii.Additional studies examining its active principles as well as nieclianisms of actions such as the effects on efflux pumps and outer membrane permeability alterations are recommended.展开更多
Alteration of technological and optical states of glass activated with chloride ions, entered to the surface of quartz sand and quartz grain by way of sodium chloride was investigated in the article. Concentration opt...Alteration of technological and optical states of glass activated with chloride ions, entered to the surface of quartz sand and quartz grain by way of sodium chloride was investigated in the article. Concentration optimum of activating agent was determined.展开更多
Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of China.The surface chemical properties of carbon have great influence on its desulphurization performance...Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of China.The surface chemical properties of carbon have great influence on its desulphurization performance.A series of activated carbons (ACs) were prepared using HNO3,H2O2,NH3·H2O and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation process.The ACs were physically and chemically characterized by iodine and SO2 adsorption,ultimate analysis,Boehm titration,and temperature-programmed reduction (TPR).Results showed that the iodine number and desulphurization capacity of NH3·H2O activated carbon (AC-NH3) increase with both activation time,and its desulphurization capacity also increases with the concentration of activation agent.However,HNO3 activated carbon (AC-HNO3) and H2O2 activated carbon (AC-H2O2) exhibit more complex behavior.Only their iodine numbers increase monotonously with activation time.Compared with steam activated AC (AC-H2O),the nitrogen content increases 0.232% in AC-NH3 and 0.077% in AC-HNO3.The amount of total basic site on AC-HNO3 is 0.19 mmol·g-1 higher than that on AC-H2O.H2O2 activation introduces an additional 0.08 mmol·g-1 carboxyl groups to AC surface than that introduced by steam activation.The desulphurization capacity of ACs in simulate flue gas desulphurization decreases as follows: AC-NH3 】 AC-HNO3 】 AC-H2O2 】 AC-H2O.This sequence is in accord with the SO2 catalytic oxidation/oxidation ratio in the absence of oxygen and the oxidation property reflected by TPR.In the presence of oxygen,all adsorbed SO2 on ACs can be oxidized into SO3.The desulphurization capacity increases differently according to the activation agents;the desulphurization capacity of AC-NH3 and AC-HNO3 improves by 4.8 times,yet AC-H2O increases only by 2.62 as compared with the desulphurization of corresponding ACs in absence of oxygen.展开更多
文摘SrTiO_3 nano-crystal samples with floccule or flake crystal morphology,which were indexed as a perovskite-type crystal structure based on the results of XRD and TEM,were successfully prepared by one-step liquid reaction method.And the growth mechanism of the SrTiO_3 nano-crystals under the liquid condition with/without adding the surface active agent was investigated.It was found that adding the surface active agent contributes to the processing in which the ions gathering bodies transit to a more stable phase through the chemical reaction and form the flake SrTiO_3 nano-crystals.
基金Acknowledgment is made to the Donors of the American Chemical Society Petroleum Research Fund for support of this research.
文摘New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable energy source for heating and electricity generation due to its high combustion value.Currently,natural gas accounts for a large portion of electricity generation and chemical feedstock in manufacturing plastics and other commercially important organic chemicals.In the near future,natural gas will be widely used as a fuel for vehicles.Therefore,a practical storage device for its storage and transportation is very beneficial to the deployment of natural gas as an energy source for new technologies.In this tutorial review,biomaterials-based carbon monoliths(CMs),one kind of carbonaceous material,was reviewed as an adsorbent for natural gas(methane)adsorption and storage.
基金supported by the Thailand Research Fund(BRG 5580015.Fiscal year 2012-2014)Miss Pinanong Na-Phatthalung and Miss Thanyaluck Siriyong are funded by Natural Product Research Center of Excellence Postgraduate Scholarship
文摘Objective:To investigate the efficacy of 17 ethnomedicinal plants belonging to Apocynaceae family used in combination with 16 conventional antibiotics against non-multidrug resistant-,multidrug resistant(MDR)-.and extensive drug resistant(XDR) Acinetobacter baumannii(A.haumannii).Methods:Antibacterial activity and resistance modifying ability of 272combinations were determined by growth inhibition assays and further confirmed by time-kill assay.Results:Among the combinations of the antibiotics with Apocynaceae ethanol extracts on this pathogen,15(5%) had synergistic effects,23(8%) had partial synergistic effects and 234(86%) had no effects.Synergistic activity was observed mostly when the Apocynaceae extracts were combined with rifampicin or cefazolin.Interestingly.10 out of 17 combinations between the extracts and rifampicin displayed synergistic or partial synergistic behaviors.Holarrhena antidysenterica extract was additionally tested to restore rifampicin activity against clinical isolates of MDR and XDR A.haumannii.With respect to total or partial synergy,70%was XDR A.haumannii isolates and 66%was MDR A.haumannii isolates.Conclusions:Holarrhena antidysenterica extract clearly demonstrated the ability to restore rifampicin activity against both A.haumannii ATCC19606 and clinically isolated A.haumannii.Additional studies examining its active principles as well as nieclianisms of actions such as the effects on efflux pumps and outer membrane permeability alterations are recommended.
文摘Alteration of technological and optical states of glass activated with chloride ions, entered to the surface of quartz sand and quartz grain by way of sodium chloride was investigated in the article. Concentration optimum of activating agent was determined.
基金supported by the National Natural Science Foundation of China (Grant No. 50204011)the Chemical and Environmental Engineering Lab for the TP-5000(II) adsorption instrument
文摘Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of China.The surface chemical properties of carbon have great influence on its desulphurization performance.A series of activated carbons (ACs) were prepared using HNO3,H2O2,NH3·H2O and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation process.The ACs were physically and chemically characterized by iodine and SO2 adsorption,ultimate analysis,Boehm titration,and temperature-programmed reduction (TPR).Results showed that the iodine number and desulphurization capacity of NH3·H2O activated carbon (AC-NH3) increase with both activation time,and its desulphurization capacity also increases with the concentration of activation agent.However,HNO3 activated carbon (AC-HNO3) and H2O2 activated carbon (AC-H2O2) exhibit more complex behavior.Only their iodine numbers increase monotonously with activation time.Compared with steam activated AC (AC-H2O),the nitrogen content increases 0.232% in AC-NH3 and 0.077% in AC-HNO3.The amount of total basic site on AC-HNO3 is 0.19 mmol·g-1 higher than that on AC-H2O.H2O2 activation introduces an additional 0.08 mmol·g-1 carboxyl groups to AC surface than that introduced by steam activation.The desulphurization capacity of ACs in simulate flue gas desulphurization decreases as follows: AC-NH3 】 AC-HNO3 】 AC-H2O2 】 AC-H2O.This sequence is in accord with the SO2 catalytic oxidation/oxidation ratio in the absence of oxygen and the oxidation property reflected by TPR.In the presence of oxygen,all adsorbed SO2 on ACs can be oxidized into SO3.The desulphurization capacity increases differently according to the activation agents;the desulphurization capacity of AC-NH3 and AC-HNO3 improves by 4.8 times,yet AC-H2O increases only by 2.62 as compared with the desulphurization of corresponding ACs in absence of oxygen.
