Organic?inorganic hybrid coating on the surface of aluminum-tube used in refrigeration equipment using cerium ion (III) as the additive was fabricated by sol?gel method, and the structure of the coating was confirmed ...Organic?inorganic hybrid coating on the surface of aluminum-tube used in refrigeration equipment using cerium ion (III) as the additive was fabricated by sol?gel method, and the structure of the coating was confirmed by FT-IR. The results of the characterization show that the corrosion resistance of the coating with 1.5 mmol/L cerium ion (III) gains significant improvement, in which the colour retention time of CuSO4 extends to 500 s, the anti-acid and alkali corrosion rates reduce by 67% and 70% compared with the blank one, respectively, and the salt spray tests also show good corrosion resistance. The electrochemical tests demonstrate that the self-corrosion current density and potential of the sample with hybrid coating are about 2.877×10?7 A/cm2 and?0.550 V, respectively. The metallographic and SEM images show that the hybrid coating is uniform and dense, and the EDS analysis confirms that the coating is mainly composed of Al, Si and Ce elements.展开更多
The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences ...The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences on physiochemical properties and catalytic activity of the resulting Ni/Al2O3 catalyst, but little influence on the selec-tivity. At a comparable amount of Ni loading, the catalytic activity of Ni/Al2O3 prepared with alumina support of smaller particle size is lower. The reduction behavior of the catalyst is a key factor in determining the catalytic activity of Ni/Al2O3 catalyst. The supported nickel catalyst 10.3Ni/Al2O3-3 improves the life span of the membrane by reducing fouling on the membrane surface compared to nano-sized nickel.展开更多
To observe effect of moxibustion at Zusanli （足三里 ST 36） and Liangmen （梁门 ST 21 ） on expression of heat shock protein 70 （HSP70） in gastric mucosa of the rat of stress ulcer （SU） to explore the mechanism o...To observe effect of moxibustion at Zusanli （足三里 ST 36） and Liangmen （梁门 ST 21 ） on expression of heat shock protein 70 （HSP70） in gastric mucosa of the rat of stress ulcer （SU） to explore the mechanism of moxibustion in resisting oxidative injury of the gastric mucosa. Methods： Sixty SD rats were evenly randomized into 4 groups, a blank group, a model group, an acupoint moxibustion group and a non-acupoint moxibustion group. Water restraint stress （WRS） method was used to make stress gastric ulcer rat model. The ulcerative index （Ul） of gastric mucosa was evaluated by using GUTH method, the gastric mu- cosa blood flux （GMBF） was detected by a laser Doppler bloodflow monitor, and HSP70 expression and malondialdehyde （MDA） content in the gastric mucosa were determined respectively with immunohistochemical and thiobarbiturate methods. Results： Moxibustion at Zusanli （ST 36） and Liangmen （ST 21 ） significantly de- creased Ul, up-regulated HSP70 expression, increased GMBF, and decreased MDA content in the gastric mucosa in the rat of stress gastric ulcer, with significant differences as compared with the model group and the non-acupoint moxibustion group （P 〈 0.05 or P 〈 0.01 ）. Conclusion： Moxibustion at Zusanli （ST 36） and Liangmen （ST 21 ） can induce high expression of HSP70 and decrease MDA content in the gastric mucosa, so as to resist oxidative injury, with relative acupoint specificity.展开更多
Numerical calculations were conducted to simulate the flow and mass transfer in narrow membrane channels equipped with delta winglets, which are often used as longitudinal vortex generators to enhance heat transfer in...Numerical calculations were conducted to simulate the flow and mass transfer in narrow membrane channels equipped with delta winglets, which are often used as longitudinal vortex generators to enhance heat transfer in heat exchanger applications. The channel consists of an impermeable solid wall and a membrane. The delta winglets are attached to the solid wall surface to enhance the mass transfer near the membrane surface and suppress the concentration polarization. The winglet performance was evaluated in terms of concentration polarization factor versus consumed pumping power. Calculations were implemented for NaCl solution flow in a membrane channel having a height of 2.0 mm for Reynolds numbers ranging from 400 to 1000. The delta wing- lets were optimized under equal pumping power condition, and the results of optimization suggest winglet height of 5/6 of the channel height, aspect ratio of 2.0, attack angle of 30% and a winglet interval equal to the channel height The optimal delta winglets were compared with the optimal rectangular winglets we found previously, and it is shown that the rectangular winglets yield a somewhat better performance than the delta winglets. @ 2015 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.展开更多
A method for preparation of particle crystal film constructed from monodisperse silica colloidal particles in diameter of about 300 nm is reported. The films were prepared from an ethanol suspension by vertical deposi...A method for preparation of particle crystal film constructed from monodisperse silica colloidal particles in diameter of about 300 nm is reported. The films were prepared from an ethanol suspension by vertical deposition that relies on capillary forces to assemble colloidal crystal particles on a vertical substrate. The 3D ordered films were characterized by transmission spectra and scanning electric microscope (SEM). The effect of evaporation temperature, particle concentration and sintered temperature on the quality of colloidal particle crystal film was investigated.展开更多
The paper aims to expand the application of natural marine algae. Marine diatoms, which have intricate frustule struc- tures, can serve as bio-template for preparing three-dimensional materials. A simple and effective...The paper aims to expand the application of natural marine algae. Marine diatoms, which have intricate frustule struc- tures, can serve as bio-template for preparing three-dimensional materials. A simple and effective approach to synthesize the corru- gated agaric-like biomorphic TiO2 templated with frustule of Coscinodiscus sp. is reported. In the sol-gel preparation process, the titania-coating on the frustule is prepared through the deposition and condensation with the aid of acetylacetone （acac） as a control- ling agent to make the precursor Ti（BuO）4 hydrolyze slowly. The as-prepared titania-coated frustule and biomorphic TiOz is charac- terized by scanning electron microscopy （SEM） attached with energy dispersive X-ray spectrometer （EMAX） and X-ray diffraction （XRD）. The microstructure of the corresponding titania nanoparticles appears to be sphere with the diameters distributed around 10-20nm. The templating process is repeated for three cycles. Subsequently, the three-dimensional freestanding corrugated aga- ric-like biomorphic TiO2 structure is obtained by a selective removal in the NaOH solution. As far as we known, the 3D freestanding corrugated agaric-like biomorphic TiOz with greatly increased surface area is obtained for the first time.展开更多
A novel method for on-site determination of trace iron was developed using membrane preconcentration and spectrophotometric detection. Fe（II）-ferrozine complex was reacted with cetyltrimethylammonium bromide （CTAB...A novel method for on-site determination of trace iron was developed using membrane preconcentration and spectrophotometric detection. Fe（II）-ferrozine complex was reacted with cetyltrimethylammonium bromide （CTAB） to form a Fe（II）-ferrozine-CTAB paired compound, which was collected on a membrane by filtration under vacuum. The membrane was immersed in 2 mL of ethanol-nitric acid and the absorbance of the solution measured for quantitative analysis. Various factors affecting the iron collection and determination were investigated. With different sample preconcentration volumes, the range of determination was broadened to 0.5-120 ~tg/L. The detection limit of this method reached 0.19 ktg/L and the recoveries were between 97.2 and 109% when the concentration enrichment was about 45. The relative standard deviation （n = 7） was 1.9% for samples containing 10 ~g/L Fe. Twelve seawater samples were analyzed on-site using the proposed method, and two were also analyzed in inductively coupled plasma mass spectrometry. No significant difference was shown between the two methods by the Student＇s t-test. The method has also been used on-site for iron enrichment experiments with phytoplankton and concluded to be simple, accurate and inexpensive.展开更多
Objective： To introduce a new animal model of graded mechanical primary brainstem injury （BSI）. Methods： Altogether 45 rabbits were subjected to BSI by type II biological impact machine designed by the Third Mili...Objective： To introduce a new animal model of graded mechanical primary brainstem injury （BSI）. Methods： Altogether 45 rabbits were subjected to BSI by type II biological impact machine designed by the Third Military Medical University. The animals were divided into 4 experimental groups （n=10） and 1 control group （n=5） ac- cording to different magnitudes of impact pressure imposed on the occipital nodule： Group 1,500-520 kPa; Group 2, 520- 540 kPa; Group 3,540-560 kPa; Group 4, 560-580 kPa and Group 5, 0 kPa with 20 kPa increase in each grade. The im- pact depth was a constant 0.5 cm. After injury, the clinical symptoms and signs as well as pathological changes were observed. Results： Rabbits in Group 1 revealed mild physiologi- cal reaction of BSI. They had localized cerebral contusion with punctate hemorrhage and subarachnoid hemorrhage （SAH） was limited to the peripheral tissues at the impact area. In Group 2, obvious physiological reaction was observed. Local pathological lesions reached the superfi- cial layer of brainstem tissues; focal hemorrhage and girdle- shaped SAH in basilar pon were observed under microscope. In Group 3, BSI was more severe with a long respiratory depression. Pathological lesions reached the inner portionof brainstem with massive hemorrhage and the whole brainstem was wrapped by subarachnoid hematoma. In Group 4, most rabbits died due to severe BSI. Pathological lesions deepened to the central brainstem with wide patho- logical change, rapture of the medulla oblongata central canal. Group 5 was the control group, with normal brainstem structure and no lesion observed. Conclusion： This model successfully simulates differ- ent levels ofbrainstem mechanical injury and clearly shows the subsequent pathological changes following injury. It takes two external parameters （impact pressure and depth） and has a similar injury mechanism to clinical accelerating BSI. Moreover it is reproducible and stable, thus being be- neficial for exploring pathophysiological mechanism, diag- nosis and forensic identification of various degrees of BSI.展开更多
基金Project(51404038)supported by the National Natural Science Foundation of China
文摘Organic?inorganic hybrid coating on the surface of aluminum-tube used in refrigeration equipment using cerium ion (III) as the additive was fabricated by sol?gel method, and the structure of the coating was confirmed by FT-IR. The results of the characterization show that the corrosion resistance of the coating with 1.5 mmol/L cerium ion (III) gains significant improvement, in which the colour retention time of CuSO4 extends to 500 s, the anti-acid and alkali corrosion rates reduce by 67% and 70% compared with the blank one, respectively, and the salt spray tests also show good corrosion resistance. The electrochemical tests demonstrate that the self-corrosion current density and potential of the sample with hybrid coating are about 2.877×10?7 A/cm2 and?0.550 V, respectively. The metallographic and SEM images show that the hybrid coating is uniform and dense, and the EDS analysis confirms that the coating is mainly composed of Al, Si and Ce elements.
基金Supported by the Special Funds for Major State Basic Research Program of China （No.2003CB615702）, the National Natural Science Foundation of China （No.20636020） and the Natural Science Foundation of Jiangsu Province （No.BK2006722）.
文摘The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences on physiochemical properties and catalytic activity of the resulting Ni/Al2O3 catalyst, but little influence on the selec-tivity. At a comparable amount of Ni loading, the catalytic activity of Ni/Al2O3 prepared with alumina support of smaller particle size is lower. The reduction behavior of the catalyst is a key factor in determining the catalytic activity of Ni/Al2O3 catalyst. The supported nickel catalyst 10.3Ni/Al2O3-3 improves the life span of the membrane by reducing fouling on the membrane surface compared to nano-sized nickel.
文摘To observe effect of moxibustion at Zusanli （足三里 ST 36） and Liangmen （梁门 ST 21 ） on expression of heat shock protein 70 （HSP70） in gastric mucosa of the rat of stress ulcer （SU） to explore the mechanism of moxibustion in resisting oxidative injury of the gastric mucosa. Methods： Sixty SD rats were evenly randomized into 4 groups, a blank group, a model group, an acupoint moxibustion group and a non-acupoint moxibustion group. Water restraint stress （WRS） method was used to make stress gastric ulcer rat model. The ulcerative index （Ul） of gastric mucosa was evaluated by using GUTH method, the gastric mu- cosa blood flux （GMBF） was detected by a laser Doppler bloodflow monitor, and HSP70 expression and malondialdehyde （MDA） content in the gastric mucosa were determined respectively with immunohistochemical and thiobarbiturate methods. Results： Moxibustion at Zusanli （ST 36） and Liangmen （ST 21 ） significantly de- creased Ul, up-regulated HSP70 expression, increased GMBF, and decreased MDA content in the gastric mucosa in the rat of stress gastric ulcer, with significant differences as compared with the model group and the non-acupoint moxibustion group （P 〈 0.05 or P 〈 0.01 ）. Conclusion： Moxibustion at Zusanli （ST 36） and Liangmen （ST 21 ） can induce high expression of HSP70 and decrease MDA content in the gastric mucosa, so as to resist oxidative injury, with relative acupoint specificity.
基金Supported by Tsinghua University Initiative Scientific Research Program(20131089319)
文摘Numerical calculations were conducted to simulate the flow and mass transfer in narrow membrane channels equipped with delta winglets, which are often used as longitudinal vortex generators to enhance heat transfer in heat exchanger applications. The channel consists of an impermeable solid wall and a membrane. The delta winglets are attached to the solid wall surface to enhance the mass transfer near the membrane surface and suppress the concentration polarization. The winglet performance was evaluated in terms of concentration polarization factor versus consumed pumping power. Calculations were implemented for NaCl solution flow in a membrane channel having a height of 2.0 mm for Reynolds numbers ranging from 400 to 1000. The delta wing- lets were optimized under equal pumping power condition, and the results of optimization suggest winglet height of 5/6 of the channel height, aspect ratio of 2.0, attack angle of 30% and a winglet interval equal to the channel height The optimal delta winglets were compared with the optimal rectangular winglets we found previously, and it is shown that the rectangular winglets yield a somewhat better performance than the delta winglets. @ 2015 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.
基金Supported by the Chinese National Key Basic Research Special Fund (No.2001CB6104) and the National Natural Science Foundation of China(No.20076027)
文摘A method for preparation of particle crystal film constructed from monodisperse silica colloidal particles in diameter of about 300 nm is reported. The films were prepared from an ethanol suspension by vertical deposition that relies on capillary forces to assemble colloidal crystal particles on a vertical substrate. The 3D ordered films were characterized by transmission spectra and scanning electric microscope (SEM). The effect of evaporation temperature, particle concentration and sintered temperature on the quality of colloidal particle crystal film was investigated.
基金supported by the Key Scientific and Technological Projects of Shandong Province (2011GGX10401)
文摘The paper aims to expand the application of natural marine algae. Marine diatoms, which have intricate frustule struc- tures, can serve as bio-template for preparing three-dimensional materials. A simple and effective approach to synthesize the corru- gated agaric-like biomorphic TiO2 templated with frustule of Coscinodiscus sp. is reported. In the sol-gel preparation process, the titania-coating on the frustule is prepared through the deposition and condensation with the aid of acetylacetone （acac） as a control- ling agent to make the precursor Ti（BuO）4 hydrolyze slowly. The as-prepared titania-coated frustule and biomorphic TiOz is charac- terized by scanning electron microscopy （SEM） attached with energy dispersive X-ray spectrometer （EMAX） and X-ray diffraction （XRD）. The microstructure of the corresponding titania nanoparticles appears to be sphere with the diameters distributed around 10-20nm. The templating process is repeated for three cycles. Subsequently, the three-dimensional freestanding corrugated aga- ric-like biomorphic TiO2 structure is obtained by a selective removal in the NaOH solution. As far as we known, the 3D freestanding corrugated agaric-like biomorphic TiOz with greatly increased surface area is obtained for the first time.
基金Supported by State Key Laboratory of Marine Environmental Science(MEL)Funds(No.MELRI1001)
文摘A novel method for on-site determination of trace iron was developed using membrane preconcentration and spectrophotometric detection. Fe（II）-ferrozine complex was reacted with cetyltrimethylammonium bromide （CTAB） to form a Fe（II）-ferrozine-CTAB paired compound, which was collected on a membrane by filtration under vacuum. The membrane was immersed in 2 mL of ethanol-nitric acid and the absorbance of the solution measured for quantitative analysis. Various factors affecting the iron collection and determination were investigated. With different sample preconcentration volumes, the range of determination was broadened to 0.5-120 ~tg/L. The detection limit of this method reached 0.19 ktg/L and the recoveries were between 97.2 and 109% when the concentration enrichment was about 45. The relative standard deviation （n = 7） was 1.9% for samples containing 10 ~g/L Fe. Twelve seawater samples were analyzed on-site using the proposed method, and two were also analyzed in inductively coupled plasma mass spectrometry. No significant difference was shown between the two methods by the Student＇s t-test. The method has also been used on-site for iron enrichment experiments with phytoplankton and concluded to be simple, accurate and inexpensive.
基金The paper was supported by the National Natural Science Foundation of China，the Natural Science Foundation of Chongqing of China，the Key Projects Foundation of the Ministry of Public Security
文摘Objective： To introduce a new animal model of graded mechanical primary brainstem injury （BSI）. Methods： Altogether 45 rabbits were subjected to BSI by type II biological impact machine designed by the Third Military Medical University. The animals were divided into 4 experimental groups （n=10） and 1 control group （n=5） ac- cording to different magnitudes of impact pressure imposed on the occipital nodule： Group 1,500-520 kPa; Group 2, 520- 540 kPa; Group 3,540-560 kPa; Group 4, 560-580 kPa and Group 5, 0 kPa with 20 kPa increase in each grade. The im- pact depth was a constant 0.5 cm. After injury, the clinical symptoms and signs as well as pathological changes were observed. Results： Rabbits in Group 1 revealed mild physiologi- cal reaction of BSI. They had localized cerebral contusion with punctate hemorrhage and subarachnoid hemorrhage （SAH） was limited to the peripheral tissues at the impact area. In Group 2, obvious physiological reaction was observed. Local pathological lesions reached the superfi- cial layer of brainstem tissues; focal hemorrhage and girdle- shaped SAH in basilar pon were observed under microscope. In Group 3, BSI was more severe with a long respiratory depression. Pathological lesions reached the inner portionof brainstem with massive hemorrhage and the whole brainstem was wrapped by subarachnoid hematoma. In Group 4, most rabbits died due to severe BSI. Pathological lesions deepened to the central brainstem with wide patho- logical change, rapture of the medulla oblongata central canal. Group 5 was the control group, with normal brainstem structure and no lesion observed. Conclusion： This model successfully simulates differ- ent levels ofbrainstem mechanical injury and clearly shows the subsequent pathological changes following injury. It takes two external parameters （impact pressure and depth） and has a similar injury mechanism to clinical accelerating BSI. Moreover it is reproducible and stable, thus being be- neficial for exploring pathophysiological mechanism, diag- nosis and forensic identification of various degrees of BSI.
