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Oxidation of Fe-Cr-Ni Alloys in a Low Oxygen Partial Pressure Atmosphere to Mitigate Coke Formation
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作者 Wang Hongxia Wang Guoqing +3 位作者 Zhang Lijun Wang Shenxiang Jia Jingsheng Cui Lishan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第3期49-59,共11页
Anti-coking oxide films were prepared on a 25Cr35Ni and 35Cr45Ni alloy surface under the low oxygen partialpressure atmosphere of a H2-H2O mixture. The composition and phase structure of the oxide films were analyzed ... Anti-coking oxide films were prepared on a 25Cr35Ni and 35Cr45Ni alloy surface under the low oxygen partialpressure atmosphere of a H2-H2O mixture. The composition and phase structure of the oxide films were analyzed by energydispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The anti-cokingperformance of a mini tube made of a HP40 (25Cr35Ni) alloy was evaluated on a bench scale pyrolysis and coking test unit.The results showed that the surface Fe and Ni content decreased after the oxidation of the two alloys in a low oxygen partialpressure atmosphere. The oxide films were mainly composed of MnCr_(2)O_(4) and Cr_(2)O_(3). The average mass of coke in the minitube with oxide film decreased by 87% relative to that of a tube without an oxide film when the cracking temperature was 900℃. The ethylene, propylene, and butadiene yields in the pyrolysis tests were almost the same for the mini tubes withand without an oxide film. The oxide film on the alloy surface effectively inhibited catalytic filamentous coke formation.An industrial test showed that the run length of the cracking furnace with the in-situ coating technology was significantlyextended. 展开更多
关键词 Fe-Cr-Ni alloy low oxygen partial pressure oxide film ANTI-COKING ethylene cracking furnace in-situ coating
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Influence of oxygen partial pressure on properties of N-doped ZnO films deposited by magnetron sputtering 被引量:5
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作者 王金忠 E.ElANGOVAN +4 位作者 N.FRANCO A.ALVESE A.REGO R.MARTINS E.FORTUNATO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第12期2326-2330,共5页
N-doped ZnO films were radio frequency(RF)sputtered on glass substrates and studied as a function of oxygen partial pressure(OPP)ranging from 3.0×10-4 to 9.5×10-3 Pa.X-ray diffraction patters confirmed the p... N-doped ZnO films were radio frequency(RF)sputtered on glass substrates and studied as a function of oxygen partial pressure(OPP)ranging from 3.0×10-4 to 9.5×10-3 Pa.X-ray diffraction patters confirmed the polycrystalline nature of the deposited films.The crystalline structure is influenced by the variation of OPP.Atomic force microscopy analysis confirmed the agglomeration of the neighboring spherical grains with a sharp increase of root mean square(RMS)roughness when the OPP is increased above 1.4×10-3 Pa.X-ray photoelectron spectroscopy analysis revealed that the incorporation of N content into the film is decreased with the increase of OPP,noticeably N 1s XPS peaks are hardly identified at 9.5×10-3 Pa.The average visible transmittance(380-700 nm) is increased with the increase of OPP(from~17%to 70%),and the optical absorption edge shifts towards the shorter wavelength.The films deposited with low OPP(≤3.0×10-4 Pa)show n-type conductivity and those deposited with high OPP(≥9.0×10-4 Pa)are highly resistive(>105Ω·cm) 展开更多
关键词 ZNO oxygen partial pressure magnetron sputtering TRANSMITTANCE
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The Effect of Oxygen Partial Pressure during Active Layer Deposition on Bias Stability of a-InGaZnO TFTs 被引量:2
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作者 黄晓明 武辰飞 +3 位作者 陆海 任芳芳 朱洪波 王永进 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期171-174,共4页
The effect of oxygen partial pressure (Po2) during the channel layer deposition on bias stability of amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) is investigated. As Po2 increases fr... The effect of oxygen partial pressure (Po2) during the channel layer deposition on bias stability of amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) is investigated. As Po2 increases from 10% to 30%, it is found that the device shows enhanced bias stress stability with significantly reduced threshold voltage drift under positive gate bias stress. Based on the x-ray photoelectron spectroscopy measurement, the concentration of oxygen vacancies (Or) within the a-IGZO layer is suppressed by increasing Po2. Meanwhile, the low-frequency noise analysis indicates that the average trap density near the channel/dielectric interface continuously drops with increasing Po2. Therefore, the improved interface quality with increasing Po2 during the channel layer deposition can be attributed to the reduction of interface Ov-related defects, which agrees with the enhanced bias stress stability of the a-IGZO TFTs. 展开更多
关键词 TFT The Effect of oxygen partial pressure during Active Layer Deposition on Bias Stability of a-InGaZnO TFTs
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Effect of Oxygen Partial Pressure on Epitaxial Growth and Properties of Laser-Ablated AZO Thin Films
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作者 王传彬 LUO Sijun +1 位作者 SHEN Qiang 张联盟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期27-30,共4页
Al-doped ZnO(AZO) thin films were grown on c-sapphire substrates by laser ablation under different oxygen partial pressures(P_(O2)).The effect of P_(O2) on the crystal structure,preferred orientation as well a... Al-doped ZnO(AZO) thin films were grown on c-sapphire substrates by laser ablation under different oxygen partial pressures(P_(O2)).The effect of P_(O2) on the crystal structure,preferred orientation as well as the electrical and optical properties of the films was investigated.The structure characterizations indicated that the as-grown films were single-phased with a wurtzite ZnO structure,showing a significant c-axis orientation.The films were well crystallized and exhibited better crystallinity and denser texture when deposited at higher P_(O2).At the optimum oxygen partial pressures of 10- 15 Pa,the AZO thin films were epitaxially grown on c-sapphire substrates with the(0001) plane parallel to the substrate surface,i e,the epitaxial relationship was AZO(000 1) // A1_2O_3(000 1).With increasing P_(O2),the value of Hall carrier mobility was increased remarkably while that of carrier concentration was decreased slightly,which led to an enhancement in electrical conductivity of the AZO thin films.All the films were highly transparent with an optical transmittance higher than 85%. 展开更多
关键词 AZO thin films epitaxial growth laser ablation oxygen partial pressure electrical and optical properties
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Self-healing behavior of Ti_(2)AlC at a low oxygen partial pressure 被引量:2
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作者 Boxiang YAO Shibo LI +4 位作者 Weiwei ZHANG Wenbo YU Yang ZHOU Shukai FAN Guoping BEI 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2022年第11期1687-1695,共9页
Ti_(2)AlC,a MAX phase ceramic,has an attractive self-healing ability to restore performance via the oxidation-induced crack healing mechanism upon healing at high temperatures in air(high oxygen partial pressures).How... Ti_(2)AlC,a MAX phase ceramic,has an attractive self-healing ability to restore performance via the oxidation-induced crack healing mechanism upon healing at high temperatures in air(high oxygen partial pressures).However,such healing ability to repair damages in vacuum or low oxygen partial pressure conditions remains unknown.Here,we report on the self-healing behavior of Ti_(2)AlC at a low oxygen partial pressure of about 1 Pa.The experimental results showed that the strength recovery depends on both healing temperature and time.After healing at 1400℃for 1–4 h,the healed samples exhibited the recovered strengths even exceeding the original strength of 375 MPa.The maximum recovered strength of~422 MPa was achieved in the healed Ti_(2)AlC sample after healing at 1400 for 4 h,about 13%higher than the original strength.Damages were healed by the formed℃TiCx from the decomposition of Ti_(2)AlC.The decomposition-induced crack healing as a new mechanism in the low oxygen partial pressure condition was disclosed for the MAX ceramics.The present study illustrates that key components made of Ti_(2)AlC can prolong their service life and keep their reliability during use at high temperatures in low oxygen partial pressures. 展开更多
关键词 MAX ceramics Ti_(2)AlC SELF-HEALING low oxygen partial pressures strength recovery mechanism
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Analysis of metabolic alterations in Arabidopsis following changes in the carbon dioxide and oxygen partial pressures 被引量:2
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作者 Alexandra Florian Stefan Timm +4 位作者 Zoran Nikoloski Takayuki Tohge Hermann Bauwe Wagner L.Araujo Alisdair R.Fernie 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2014年第9期941-959,共19页
As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the atmosphere.Given the indiscriminant nature of Rubisco,the relative ... As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the atmosphere.Given the indiscriminant nature of Rubisco,the relative rates of photosynthesis and photorespiration are known to be responsive to changes in gas composition.However,comprehensive profiling methods have not yet been applied in order to characterize the wider consequences of these changes on primary metabolism in general.Moreover,although transcriptional profiling has revealed that a subset of photorespiratory enzymes are co-expressed,whether transcriptional responses play a role in short-term responses to atmospheric compositional changes remains unknown.To address these questions,plants Arabidopsis thaliana(Arabidopsis) ecotype Columbia(Col-O) grown under normal air conditions were transferred to different CO_2 and O_2 concentrations and characterized at the physiological,molecular,and metabolic levels following this transition.The results reveal alterations in the components,which are directly involved in,or supporting,photorespiration,including transcripts and metabolite levels.The results further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription and that the photorespiratory pathway is essential also in conditions in which flux through the pathway is minimized,yet suggest that flux through this pathway is not mediated at the level of transcription. 展开更多
关键词 Carbon dioxide partial pressures gene expression metabolic profiling oxygen partial pressures
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Effect of cerium addition on oxidation behavior of 25Cr20Ni alloy under low oxygen partial pressure 被引量:1
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作者 邵明增 崔立山 +1 位作者 郑雁军 邢琳琳 《Journal of Rare Earths》 SCIE EI CAS CSCD 2012年第2期164-169,共6页
The influence of Ce addition on the oxidation behavior of 25Cr20Ni alloy at 950 oC under low oxygen partial pressure was inves-tigated. The oxidized samples were characterized by using X-ray diffraction (XRD), scann... The influence of Ce addition on the oxidation behavior of 25Cr20Ni alloy at 950 oC under low oxygen partial pressure was inves-tigated. The oxidized samples were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and scratch tester to obtain the oxide phases, morphology, thickness, composition and adhesion property of the oxide scales. The experiment results indicated that a small amount of Ce addition (0.02 wt.% or 0.05 wt.%) promoted oxidation resistance and inhibited the growth of the needlelike oxide. The Ce addition also decreased the formation of MnCr2O4 but promoted the SiO2 formation un-derneath the Cr2O3, which largely contributed to the improvement of oxide scale spallation resistance. For the sample with 0.3 wt.% Ce addi-tion, the oxidation rate significantly increased and the spallation resistance of the oxide scale decreased. 展开更多
关键词 CERIUM 25Cr20Ni alloy OXIDATION low oxygen partial pressure rare earths
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Effect of Oxygen Partial Pressure on Phase Equilibria and Liquidus in CaO-Al_2O_3-FeO_x System 被引量:1
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作者 WANG Nan HUANG Wei-jun CHEN Shuai-chao CHEN Min 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2012年第11期8-12,共5页
A high temperature equilibration experiment was carried out to investigate the effect of oxygen partial pres- sure on the phase equilibria and liquidus in CaO-Al2O3- FeOx system with the intermediate oxygen partial pr... A high temperature equilibration experiment was carried out to investigate the effect of oxygen partial pres- sure on the phase equilibria and liquidus in CaO-Al2O3- FeOx system with the intermediate oxygen partial pressures of 10.13 Pa and 1.01 × 10^-3 Pa. The equilibrated phases and their compositions of the quenched samples were analyzed by using SEM/EPMA (Scanning Electron Microscope/Electron Probe Micro Analysis) and XRD (X Ray Diffraction). The phase equilibrium results include two cases, the two phase coexistence and the three-phase coexistence in the high Al2O3 region with oxygen partial pressure of either 10.13 Pa or 1.01 × 10^-3 Pa. Effects of oxygen partial pressure and temperature on the liquidus along the primary phase fields of CaO · Al2O3 and CaO · 2Al2O3 were nota hle. With the decrease of oxygen partial pressure, the liquid area expands and the liquidus of CaO · Al2O3 and CaO · 2Al2O3 primary fields moves to the Al2O3-FeOx region. On the other hand, the liquid area of CaO Al2O3-FeOx sys tem extends extremely to the high Al2O3 region with the temperature increasing from 1 400 to 1 500℃, especially at lower oxygen partial pressure. The present experiment results are in good agreement with the calculated ones by FactSage. 展开更多
关键词 oxygen partial pressure LIQUIDUS phase equilibrium CaO-Al2O3 FeOx system
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Effect of Ca^(2+) complexation on oxygen partial pressure in the urinary bladder meridian of goats
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作者 Qi WANG Hongzhi JIANG +4 位作者 Shengli CHEN Mingmin ZHANG Mingxing DING Esheng KONG Guangying HUANG 《Frontiers of Medicine》 SCIE CSCD 2009年第1期96-99,共4页
The aim of this paper was to explore the relationship between energy metabolism and the meridian phenomenon.The manner of change of oxygen partial pressure in acupoints and no-acupoints of the urinary bladder meridian... The aim of this paper was to explore the relationship between energy metabolism and the meridian phenomenon.The manner of change of oxygen partial pressure in acupoints and no-acupoints of the urinary bladder meridian of goats was observed with a needle-type tissue oxygen tension sensor after the acupuncture effect was blocked by Ca^(2+) complexation with ethylenediamine tetraacetic acid(EDTA)-Na2.The results showed that:(1)the concentration of calcium ion in urinary bladder meridian acupoints was higher than that in no-acupoints(P<0.01 or P<0.05);(2)the tissue oxygen tension in urinary bladder meridian acupoints was higher than that in no-acupoints(P<0.01);(3)the oxygen partial pressure in acupoints decreased significantly after injection with EDTA-Na2,compared with injection of either normal sodium or nothing(P<0.01);(4)the oxygen partial pressure in acupoints was higher than that in no-acupoints after EDTA-Na2 injection(P<0.01).Acupuncture could reduce oxygen partial pressure in acupoints by regulating microcirculation and increasing metabolic levels. 展开更多
关键词 oxygen partial pressure BIOSENSOR calcium channels ACUPOINT
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Efficacy of Huangma Ding or autologous platelet-rich gel for the diabetic lower extremity arterial disease patients with foot ulcers
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作者 Xue-Qin Wang Dan-Lan Pu +8 位作者 Wei-Ling Leng Xiao-Tian Lei Jiang Juan Zou La Ding Yao Jia-Zhuang Xi Li Jian Teng Miao Qi-Nan Wu 《World Journal of Diabetes》 SCIE 2024年第5期923-934,共12页
BACKGROUND Diabetes foot is one of the most serious complications of diabetes and an important cause of death and disability,traditional treatment has poor efficacy and there is an urgent need to develop a practical t... BACKGROUND Diabetes foot is one of the most serious complications of diabetes and an important cause of death and disability,traditional treatment has poor efficacy and there is an urgent need to develop a practical treatment method.AIM To investigate whether Huangma Ding or autologous platelet-rich gel(APG)treatment would benefit diabetic lower extremity arterial disease(LEAD)patients with foot ulcers.METHODS A total of 155 diabetic LEAD patients with foot ulcers were enrolled and divided into three groups:Group A(62 patients;basal treatment),Group B(38 patients;basal treatment and APG),and Group C(55 patients;basal treatment and Huangma Ding).All patients underwent routine follow-up visits for six months.After follow-up,we calculated the changes in all variables from baseline and determined the differences between groups and the relationships between parameters.RESULTS The infection status of the three groups before treatment was the same.Procalcitonin(PCT)improved after APG and Huangma Ding treatment more than after traditional treatment and was significantly greater in Group C than in Group B.Logistic regression analysis revealed that PCT was positively correlated with total amputation,primary amputation,and minor amputation rates.The ankle-brachial pressure and the transcutaneous oxygen pressure in Groups B and C were greater than those in Group A.The major amputation rate,minor amputation rate,and total amputation times in Groups B and C were lower than those in Group A.CONCLUSION Our research indicated that diabetic foot ulcers(DFUs)lead to major amputation,minor amputation,and total amputation through local infection and poor microcirculation and macrocirculation.Huangma Ding and APG were effective attreating DFUs.The clinical efficacy of Huangma Ding was better than that of autologous platelet gel,which may be related to the better control of local infection by Huangma Ding.This finding suggested that in patients with DFUs combined with coinfection,controlling infection is as important as improving circulation. 展开更多
关键词 Diabetic foot ulcer Huangma Ding Autologous platelet-rich gel Ankle-brachial index Transcutaneous oxygen partial pressure
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Influence of moderate hypothermia on cerebral oxygenation in pigs with intracranial hypertension
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作者 Yinghui Bao Yumin Liang +2 位作者 Jiyao Jiang Qizhong Luo Yicheng Lu 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第5期297-300,共4页
BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxyg... BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them. OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial. SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University. MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5-5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden). METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3-]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3- and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33-35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling. MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group. RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P 〈 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P 〈 0.05], and brain tissue pH value was higher [(7.03± 1.63), (9.40±1.30) kPa, P 〈 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P 〈 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P 〉 0.05) CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis. 展开更多
关键词 moderate hypothermia brain tissue partial oxygen pressure intracranial hypertention
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Study on Oxygen Supply and Protection of Bone Marrow in Acute Radiation injured Mice
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作者 孙汉英 刘文励 +5 位作者 肖侃艳 董凌莉 何美冬 胡永熙 沈安华 江琦 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1997年第4期229-231,243,共4页
After irradiated by & Gy 60Co γ-ray, mice were intraperitoneally injected immediately with 0.2 ml 100 % compound blood-activating soup twice a day for 10 days. The in situ ulnar bone marrow partial pressure of ox... After irradiated by & Gy 60Co γ-ray, mice were intraperitoneally injected immediately with 0.2 ml 100 % compound blood-activating soup twice a day for 10 days. The in situ ulnar bone marrow partial pressure of oxygen (PbO2) was determined in vivo before, during and after irradiation respectively. The bone marrow sections in the same part were observed. Our results showed that the normal murine ulnar PbO2 was 12.72±1. 05kpa. During irradiation, the level of PbO2 decreased to 10. 78±1. 17 kpa (P<0. 001). And 3 days after irradiation, PbO2 decreased to 9. 75±0. 52 kpa, suggesting that the commonly used 'blood-activating and stasis-eliminating' Chinese drugs could promote the rehabilitation and proliferation of bone marrow microvessels in the acute radiation injured mice, expand their areas, increase the oxygen supply of bone marrow microenviroment, thereby leading to PbO2 much higher increase than that of control group. It is also helpful in the proliferation and rehabilitation of hematopoietic cells. 展开更多
关键词 acute radiation injury bone marrow microenviroment partial pressure of oxygen 'blood-activating and stasis-eliminating'Chinese drug
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Preparation of ultrafine rhenium powders by CVD hydrogen reduction of volatile rhenium oxides 被引量:9
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作者 白猛 刘志宏 +2 位作者 周乐君 刘智勇 张传福 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期538-542,共5页
A novel CVD process for the preparation of ultrafine rhenium powders was investigated using ammonium perrhenate as starting materials. In the process, volatile rhenium oxides, such as ReO4 and Re2O7, were vaporized un... A novel CVD process for the preparation of ultrafine rhenium powders was investigated using ammonium perrhenate as starting materials. In the process, volatile rhenium oxides, such as ReO4 and Re2O7, were vaporized under a controlled oxidizing atmosphere via the pyrolysis of ammonium perrhenate, and carried into reduction zone by carrier gas, and there reduced into rhenium powders by hydrogen gas. Thermodynamic calculations indicated that Re207 could be prevented from further decomposition through controlling the oxygen partial pressure higher than 10 1.248 Pa in the pyrolysis of ammonium perrhenate. This result was further validated via DSC-TGA analysis of ammonium perrhenate. The typical rhenium powders prepared by the CVD method proposed show irregular polyhedron morphology with particle size in the range of 100-800 nm and a Ds0 of 308 nm. The specific surface area and oxygen content were measured to be 4.37 m^2/g and 0.45%, respectively. 展开更多
关键词 ultrafme rhenium powders ammonium perrhenate chemical vapor decomposition oxygen partial pressure
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Oxidation behavior of C/C composites with SiC/ZrSiO_4-SiO_2 coating 被引量:3
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作者 李杨 肖鹏 +2 位作者 李专 罗威 周伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期397-405,共9页
A SiC/ZrSiO4?SiO2 (SZS) coating was successfully fabricated on the carbon/carbon (C/C) composites by pack cementation, slurry painting and sintering to improve the anti-oxidation property and thermal shock r... A SiC/ZrSiO4?SiO2 (SZS) coating was successfully fabricated on the carbon/carbon (C/C) composites by pack cementation, slurry painting and sintering to improve the anti-oxidation property and thermal shock resistance. The anti-oxidation properties under different oxygen partial pressures (OPP) and thermal shock resistance of the SZS coating were investigated. The results show that the SZS coated sample under low OPP, corresponding to the ambient air, during isothermal oxidation was 0.54% in mass gain after 111 h oxidation at 1500 ° C and less than 0.03% in mass loss after 50 h oxidation in high OPP, corresponding to the air flow rate of 36 L/h. Additionally, the residual compressive strengths (RCS) of the SZS coated samples after oxidation for 50 h in high OPP and 80 h in low OPP remain about 70% and 72.5% of those of original C/C samples, respectively. Moreover, the mass loss of SZS coated samples subjected to the thermal cycle from 1500 ° C in high OPP to boiling water for 30 times was merely 1.61%. 展开更多
关键词 C/C composite SiC/ZrSiO4-SiO2 coating oxygen partial pressure ANTI-OXIDATION thermal shock residual compressive strength
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TcPO_(2)changes are more pronounced than SpO_(2)changes during simulated altitude changes in a hypobaric oxygen chamber:a nonrandomized controlled trial
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作者 Yang Li Liang Chen +5 位作者 Ziyu Fu Zhiwei Wang Shijun Sun Xiaorong Luan Dedong Ma Tianliang Hu 《Emergency and Critical Care Medicine》 2024年第3期105-110,共6页
Background:Hypoxia is a significant risk factor of hypertension.However,no studies have used transcutaneous tissue partial pressure of oxygen(TcPO_(2))and partial pressure of carbon dioxide(TcPCO_(2))monitors to measu... Background:Hypoxia is a significant risk factor of hypertension.However,no studies have used transcutaneous tissue partial pressure of oxygen(TcPO_(2))and partial pressure of carbon dioxide(TcPCO_(2))monitors to measure the respective partial pressures in healthy individuals.Oxygen saturation(SpO_(2))is often used for traditional monitoring of vital signs.This study investigated the changes in TcPO_(2)and SpO_(2)values during rapid changes in altitude.The trial was registered at ClinicalTrials.gov(registration no.NCT06076057).Methods:Healthy adult volunteers were instructed to sit vertically in a hypobaric oxygen chamber,which ascended from 0 m to 2500 m at a uniform speed within 10 min.The Danish Radiometer TCM4 was used to measure TcPO_(2)and TcPCO_(2)with the ventral side of the upper arm as the measurement site.The Shenzhen Kerokan P0D-1 W pulse oximeter was used to measure heart rate and SpO_(2),with values recorded once every 500 m.Results:Altogether,49 healthy volunteers were recruited between March 2023 and August 2023.With increasing altitude,TcPO_(2)and SpO_(2)decreased significantly(P<0.01).During the ascent from 0 m,TcPO_(2)began to change statistically at 500 m(P<0.05),whereas SpO_(2)began to change statistically at 1000 m(P<0.05).At the same altitude,the difference in TcPO_(2)was greater than the difference in SpO_(2).At 1000 m,there were statistically significant changes in TcPO_(2)and SpO_(2)(P<0.001).At altitudes>500 m,statistical significance was identified between TcPO_(2)in both sexes(P<0.05).Statistical significance in TcPCO_(2)and heart rate was observed at the different elevations(P<0.05).Conclusion:In acutely changing low-pressure hypoxic environments,TcPO_(2)changed more dramatically than SpO_(2). 展开更多
关键词 Altitude change Low-pressure oxygen chamber Transcutaneous oxygen saturation Transcutaneous partial pressure of oxygen
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Growth Mechanism and Characterization of ZnO 3D Nanocrystals by Laser Irradiation & Coaxially Transporting O_2
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作者 罗开玉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第6期783-786,共4页
Different three-dimension (3D) nanotetrapods, containing club-like nanocrystals, nanotetrapods and four-foot-like nanocrystals were synthesized from Zinc sheet via CO2 laser irradiation and coaxially transporting O2... Different three-dimension (3D) nanotetrapods, containing club-like nanocrystals, nanotetrapods and four-foot-like nanocrystals were synthesized from Zinc sheet via CO2 laser irradiation and coaxially transporting O2. Different nanoproducts were fabricated by changing the content of oxygen in the experiment. The morphologies, components, phase structures and optical properties of the products were investigated by a field-emission scanning electron microscopy, an X-ray diffraction, an energy dispersed X-ray spectrometer and a photoluminescence spectroscope. The X-ray diffraction spectra were obtained on a Rigaku D/max 2500PC diffractometer. The experimental results reveal that high quality ZnO nanotetrapods can be fabricated on the special parameters, and growth of ZnO nanotetrapods depends on Vapour-Liquid-Solid(VLS) model, and the content of oxygen in the gas, namely, oxygen partial pressure is one of main factors to control morphologies and optical properties ofZnO nanotetrapods; these advantages above are important for realization of optoelectronic devices. 展开更多
关键词 ZnO 3D nanotetrapods laser irradiation FABRICATION growth mechanism oxygen partial pressure
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Thermodynamics of some ZrO_2-containing ceramics
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作者 李麟 Omer Van der Biest +2 位作者 黄水根 Jef Vleugels 王佩玲 《Journal of Shanghai University(English Edition)》 CAS 2006年第1期65-73,共9页
Thermodynamic assessment in the ternary systems ZrO2 -CeO2 -Y2 O3, ZrO2 -CeO2 -Ce2 03 and the limiting binaries ZrO2 -Y2 O3, ZrO2 -CeO2, CeO2 -Y2 03, ZrO2 -Ce2O3, CeO2 -Ce2O3 as well as the modeling for oxides are rev... Thermodynamic assessment in the ternary systems ZrO2 -CeO2 -Y2 O3, ZrO2 -CeO2 -Ce2 03 and the limiting binaries ZrO2 -Y2 O3, ZrO2 -CeO2, CeO2 -Y2 03, ZrO2 -Ce2O3, CeO2 -Ce2O3 as well as the modeling for oxides are reviewed comprehensively. Based on the recent estimations on the YO1.5-CeO2, ZrO2-CeO2 and ZrO2 -YO1.6 systems, isothermal sections at 1273 and 1 973 K of the ternary CeO2- ZrO2-YO1.5system are calculated. In the system of ZrO2-CeO2-Ce2O3, the complex relation between the nonstoichiometry (y) in CeO2-x, the composition of the ZrO2 -CeO2 solid solution and the oxygen partial pressure (Po2 ) for different ZrO2 containing solid solutions CexZr1-xO2-x. are evaluated from 1 473 to 1 773 K. The relation between the degree of Ce^+4 reduction to Ce.3 under different Po2 in the fluorite CeO2-xy and CexZr1-xOz-x solid solutions at different temperatures can be used as a guide in the development of functional ceramics. 展开更多
关键词 ZRO2 Y2O3 Ce2O3 CEO2 CeO2-y C3xZr10xO2-x ceria reduction THERMODYNAMICS oxygen partial pressure phase diagram.
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Experimental Study on the Cryopreservation of LLC-PK1 Epithelial Cells with Hypoxic UW Solution
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作者 万赤丹 王春友 +2 位作者 刘涛 王宏博 杨智勇 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第4期426-428,共3页
The effects of oxygen partial pressure on cryopreservation of the cells with organ preservation solution were explored. Hypoxic UW solution was made by purging the UW solution with argon. The pig proximal tubule epith... The effects of oxygen partial pressure on cryopreservation of the cells with organ preservation solution were explored. Hypoxic UW solution was made by purging the UW solution with argon. The pig proximal tubule epithelial cells (LLC-PK1 cells) were cryopreserved in hypoxic UW solution (Ar-UW group) or standard UW solution (UW group) at 4℃ for 48 h. Trypan blue staining and LDH detection were performed to evaluate the injury of the cells. The results showed that the oxygen partial pressure in Ar-UW group was significantly declined from 242±6 mmHg to 83±10 mmHg. After cryopreservation at 4℃ for 48 h, LDH leakage rate and Trypan blue-stained rate in Ar-UW group were (11.3±3.4)% and (10.5±4.7)%, respectively, which were significantly lower than in UW group [(49.5±6.9)% and (47.6±9.3)% respectively, both P〈0.01]. It was concluded that lower oxygen partial pressure of UW solution was more beneficial to the cryopreservation of LLC. 展开更多
关键词 organ preservation solution oxygen partial pressure CRYOPRESERVATION
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Preparation and Preservation of Hypoxia UW Solution
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作者 万赤丹 王春友 +2 位作者 刘涛 程锐 杨智勇 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第5期554-556,共3页
In order to explore the method to prepare hypoxia UW solution and the stability and preservation of hypoxia UW solution, UW solution was purged by argon or air for 15 min or 60 at a flow rate of 0.8 or 2 L/min, and th... In order to explore the method to prepare hypoxia UW solution and the stability and preservation of hypoxia UW solution, UW solution was purged by argon or air for 15 min or 60 at a flow rate of 0.8 or 2 L/min, and the oxygen partial pressure of UW solution was detected. The hypoxia UW solution was exposed to the air or sealed up to preserve by using different methods, and the changes of oxygen partial pressure was tested. The results showed that oxygen partial pressure of 50 mL UW solution, purged by argon for 15 min at a flow rate of 2 L/min, was declined from 242±6 mmHg to 83±10 mmHg. After exposure to the air, oxygen partial pressure of hypoxia UW solution was gradually increased to 160±7 mmHg at 48 h. After sealed up by the centrifuge tube and plastic bad filled with argon, oxygen partial pressure of hypoxia UW solution was stable, about 88±13 mmHg at 72 h. It was concluded that oxygen of UW solution could be purged by argon efficiently. Sealed up by the centrifuge tube and plastic bag filled with argon, oxygen partial pressure of UW solution could be stabilized. 展开更多
关键词 organ preservation solution oxygen partial pressure HYPOXIA
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Effect of sliding-cup along governor vessel on tcpO_2 and tapCO_2 in Mìngmén(命门 GV 4) point of sub-healthy humans: observation on different cupping pressure 被引量:1
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作者 赵义静 陈泽林 +1 位作者 周丹 郭义 《World Journal of Acupuncture-Moxibustion》 CSCD 2015年第3期11-16,共6页
Objective To explore the effects of sliding-cup with different parameters on energy metabolism in the body by observing the effect of sliding-cup along the governor vessel on transcutaneous partial pressures of oxygen... Objective To explore the effects of sliding-cup with different parameters on energy metabolism in the body by observing the effect of sliding-cup along the governor vessel on transcutaneous partial pressures of oxygen and carbon dioxide in Mìngmén(命门 GV 4) in sub-healthy people. Methods A total of 10 sub-healthy adults at rest were observed and sliding-cup along the governor vessel were conducted with three different parameters, jar-pressure of –0.01~ –0.02 MPa with sliding-cup for 5 min, jar-pressure of –0.02~ –0.03 MPa with sliding-cup for 5 min and jar-pressure of –0.02~ –0.03 MPa with slidingcup for 3 min. Peri Flux System5000 PF5040 module was employed to monitor the changes of transcutaneous partial pressures of oxygen(tcp O2) and carbon dioxide(tcp CO2) in GV 4 at 0 min, 5 min, 10 min, 15 min, 20 min, 25 min and 30 min after sliding-cup with above different interventions in sub-healthy subjects. Results After sliding-cup, tcp O2 increased at first and then decreased over time; there was no difference in tcp O2 after sliding-cupping with different parameters(all P0.05). After sliding-cup, tcp CO2 decreased; there was no difference in tcp CO2 after sliding-cup with different parameters(all P0.05). Conclusion Sliding-cup has a sustained effect on the body and can speed up the energy metabolism in the body. 展开更多
关键词 governor vessel sliding-cup Mingmen(命门GV 4) transcutaneous partial pressure of oxygen(tcpO_2) transcutaneous partial pressure of carbon dioxide(tcpCO_2)
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