To determine and calculate the stable fluidization zone in a magnetically fluidized bed, the fluidization characteristics of magnetic particles are investigated. Four kinds of magnetic particles with different average...To determine and calculate the stable fluidization zone in a magnetically fluidized bed, the fluidization characteristics of magnetic particles are investigated. Four kinds of magnetic particles with different average diameters, ranging from 231 to 512 μm, are fluidized in the presence of magnetic fields with specified values of the intensity in the range of zero to 7330 A/m, and the particle fluidization curves are plotted. For marking the stable fluidization zone in the curves, the minimum bubbling velocities of particles are measured by the pressure-drop fluctuation. Based on the fluidization curves, the influences of the average particle diameter and magnetic field intensity on the zone are analyzed and discussed. A correlation to determine the stable fluidization zone is derived from the experimental data, using three dimensionless numbers, i. e., the ratio of magnetic potential to gravity potential, the Reynolds number and the Archimedes number. Compared with available data reported, it is shown that the correlation is more simplified to predict relative parameters for the bed operating in the state of stable fluidization under reasonable conditions.展开更多
Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and ...Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients increased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.展开更多
In order to study the settling mechanism of particles in an air-solid magnetically stabilized fluidized bed(MSFB) for separation,we carried out free settling and quasi-zero settling tests on the tracing particles.The ...In order to study the settling mechanism of particles in an air-solid magnetically stabilized fluidized bed(MSFB) for separation,we carried out free settling and quasi-zero settling tests on the tracing particles.The results show that the main resistance forces as the tracing particles settled in an air-solid MSFB were motion resistance force and yield force.The motion resistance and yield forces greatly hindered the free settling of the particles by greatly decreasing the acceleration for settling process of the particles.The acceleration decreased from 3022.62 cm/s 2 to zero in 0.1 s,and in the end,the particles stopped in the air-solid MSFB.The yield force on particles increased with increasing the magnetic field intensity,resulting in decrease of the quasi-zero settling displacement.However,the yield force on particles decreased with increasing the fluidized air velocity,leading to increase of the quasi-zero settling displacement.When the structure and operating parameters of the air-solid MSFB were set up,the yield stress on particles stopped in an air-solid MSFB was a function of diameter and density of particles.The settling displacements of equal diameter particles increased with increasing their densities,and the settling displacements of equal density particles increased with increasing their diameters.展开更多
This article introduces the solid acid catalyst for isobutene/butylenes alkylation, the HTS Ti/Si zeolite for ammonoxidation of cyclohexanone and the noncrystalline alloy catalyst and magnetically stabi- lized bed for...This article introduces the solid acid catalyst for isobutene/butylenes alkylation, the HTS Ti/Si zeolite for ammonoxidation of cyclohexanone and the noncrystalline alloy catalyst and magnetically stabi- lized bed for hydrofining of caprolactam that were developed recently by SINOPEC Research Institute of Petroleum Processing (RIPP).展开更多
The mechanism of bolt support is an important topic in mining engineering and slope treatment. The artificial material and loading system were self-developed to study the influence of bedding cohesion and bolt number ...The mechanism of bolt support is an important topic in mining engineering and slope treatment. The artificial material and loading system were self-developed to study the influence of bedding cohesion and bolt number on the anchoring behavior of bedded rock mass. The results show that, both peak strength and elasticity modulus increase gradually with the increase of bedding cohesion and bolt number. The axial stress–strain curve of bedded rock mass under the reinforcement of bolts presents the features of strain-softening and secondary strengthening. Finally, anchoring behavior of bedded rock mass with different bolt numbers was simulated by using FLAC3 D numerical program and the results were compared with the experimental results. This study can provide certain bases to the stability control and support design of bedded rock mass in roadway.展开更多
Acute coronary syndrome (ACS) refers to a spectrum of clinical presentations ranging from unstable angina to non-ST-segment elevation myocardial infarction (NSTEMI) to ST-segment elevation myocardial infarction (...Acute coronary syndrome (ACS) refers to a spectrum of clinical presentations ranging from unstable angina to non-ST-segment elevation myocardial infarction (NSTEMI) to ST-segment elevation myocardial infarction (STEMI). Aortic dissection, intramural hematoma and penetrating atherosclerotic ulcer (PAU) are three major acute aortic syndromes (AAS).展开更多
AIM: To investigate endoscopic and clinicopathologic characteristics of early gastric cancer (EGC) according to microsatellite instability phenotype. METHODS: Data were retrospectively collected from a single tert...AIM: To investigate endoscopic and clinicopathologic characteristics of early gastric cancer (EGC) according to microsatellite instability phenotype. METHODS: Data were retrospectively collected from a single tertiary referral center. Of 981 EGC patients surgically treated between December 2003 and October 2007, 73 consecutive EGC patients with two or more microsatellite instability (MSI) mutation [high MSI (MSI-H)] and 146 consecutive EGC patients with one or no MSI mutation (non-MSI-H) were selected. The endoscopic and clinicopathologic features were compared between the MSI-H and non-MSI-H EGC groups.RESULTS: In terms of endoscopic characteristics, MSI-H EGCs more frequently presented with elevated pattern (OR 4.38, 95% Cl: 2.40-8.01, P 〈 0.001), moderate- to-severe atrophy in the surrounding mucosa (OR 1.91, 95% CI: 1.05-3.47, P = 0.033), antral location (OR 3.99, 95% CI: 2.12-7.52, P 〈 0.001) and synchronous le- sions, compared to non-MSI-H EGCs (OR 2.65, 95% CI: 1.16-6.07, P = 0.021). Other significant clinicopatholog- ic characteristics of MSI-H EGC included predominance of female sex (OR 2.77, 95% CI: 1.53-4.99, P 〈 0.001), older age (〉 70 years) (OR 3.30, 95% CI: 1.57-6.92, P = 0.002), better histologic differentiation (OR 2.35, 95% Cl: 1.27-4.34, P = 0.007), intestinal type by Lau- ren classification (OR 2.34, 95% CI: 1.15-4.76, P = 0.019), absence of a signet ring cell component (OR 2.44, 95% CI: 1.02-5.86, P = 0.046), presence of mu- cinous component (OR 5.06, 95% Cl: 1.27-20.17, P = 0.022), moderate-to-severe lymphoid stromal reaction (OR 3.95, 95% CI: 1.59-9.80, P = 0.003), and co-exist- ing underlying adenoma (OR 2.66, 95% CI: 1.43-4.95, P = 0.002). CONCLUSION: MSI-H EGC is associated with unique endoscopic and clinicopathologic characteristics includ- ing frequent presentation in protruded type, co-exist- ing underlying adenoma, and synchronous lesions.展开更多
A new salty and sandy desert of ca 5 million ha has emerged on the exposed Aral Sea bed. Every year, 170-200 tons of salt and dust rise into the air and fall on the territory of the Republic of Karakalpakstan. A numbe...A new salty and sandy desert of ca 5 million ha has emerged on the exposed Aral Sea bed. Every year, 170-200 tons of salt and dust rise into the air and fall on the territory of the Republic of Karakalpakstan. A number of experiments have been cond.ucted in order to study the salt tolerance of plants and select drought- and salt-resistant plant species, which show a wide ecological range, to fix quick-sand dunes on the exposed Aral Sea bed. Among the studied species of Calligonum genus C. caput-medusae Schrenk was the most resistant to the saline solution. At the end of the vegetation experiment, the survivability of individuals constituted 44.1% at the concentration of 1.0% of sodium chloride. Artemisiaferganensis Krasch. ex Poljak. and Salsola richteri (Moq.) Kar. ex Litv. showed a good resistance to the concentration of saline solution as high as 150 ram, at which no dried plants were recorded. As the concentration grew to 300 mM, the survivability of Artemisiaferganensis dropped to 40.0% while 66.7 Salsola richteri individuals were developing successfully. An almost similar result was obtained during the experiment on Nitraria schoberi L.. The survivability ofKrascheninnikovia ewersmanniana (Stschegl. ex Losinsk.) Grub. individuals significantly decreased at the concentration of 200 mm (33.4%), while for Agropyron cristatum the concentration of 300 mm was threshold, at which the survivability of individuals was below 3.3%. The most resistant to the deflation of sands on the exposed bed were Salsola richteri and Calligonum caput-medusae, whose survivability on the sandy dunes was 17%-41%.展开更多
The Qiangsheng gold deposit belongs to quartz vein type. The fluid inclusions consist of four types: aqueous single-phase inclusions, aqueous two-phase inclusions, carbonated two-phase inclusions and carbona- ted thr...The Qiangsheng gold deposit belongs to quartz vein type. The fluid inclusions consist of four types: aqueous single-phase inclusions, aqueous two-phase inclusions, carbonated two-phase inclusions and carbona- ted three-phase inclusions. The fluid inclusions are characterized by low salinity (5%-9% NaCl eqv) , low density (0.66-0.72 g/cm^3 ) and medium temperature (210℃-250℃). The pressure of ore-forming is 60-95 MPa and the metallogenic depth is about 5.49-7.56 km. During the mineralizing process, ore-forming fluid under- went fluid unmixing in CO2-H2O-NaCl system. The stable isotope resuhs indicate that the ore-forming fluids mainly generated from mantle, with the participation of a small amount of atmospheric water. Comprehensive studies have suggested that Qiangsheng gold deposit belongs to the type of mesothermal hydrotherm with mantlederived fluid participating in mineralization.展开更多
Sponsored by NSFC, a research team led by Prof. Enze Min (CAS Member) from Research Institute of Petroleum Processing, through 20 years' effort, settled the puzzled grave issue that amorphous alloy material has sm...Sponsored by NSFC, a research team led by Prof. Enze Min (CAS Member) from Research Institute of Petroleum Processing, through 20 years' effort, settled the puzzled grave issue that amorphous alloy material has small specific surface area and low thermal stability. At the same time, they developed magnetic stabilization bed. Their innovation in catalyst and reaction process and in their project - 'catalytic chemistry展开更多
The present study reports a highly selective and stable catalytic approach for producing tetralin, an important chemical, solvent, and H2 storage material. Transition metal phosphides (MOP, Ni2P, Co2P, and Fe2P) wer...The present study reports a highly selective and stable catalytic approach for producing tetralin, an important chemical, solvent, and H2 storage material. Transition metal phosphides (MOP, Ni2P, Co2P, and Fe2P) were prepared by wet impregnation and temperature-programmed reduction and characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), EDX mapping, scanning electron microscopy (SEM), transmission electron microscopy (TEM), brunauer-emmett- teller (BET), temperature-programmed desorption of ammonia (NH3-TPD), and fourier transform infrared spectroscopy of pyridine (pyridine-FTIR). Of all the transition metal phosphides MoP was formed at a lower reduction temperature, which resuited in smaller particle size that enhanced the overall surface area of the catalyst. The existence of weak, moderate, and Lewis acidic sites over MoP were responsible for its high tetralin selectivity (90%) and stability during the 100 h reaction on-stream in a fixed-bed reactor.展开更多
基金The National Natural Science Foundation of China(No50576013)
文摘To determine and calculate the stable fluidization zone in a magnetically fluidized bed, the fluidization characteristics of magnetic particles are investigated. Four kinds of magnetic particles with different average diameters, ranging from 231 to 512 μm, are fluidized in the presence of magnetic fields with specified values of the intensity in the range of zero to 7330 A/m, and the particle fluidization curves are plotted. For marking the stable fluidization zone in the curves, the minimum bubbling velocities of particles are measured by the pressure-drop fluctuation. Based on the fluidization curves, the influences of the average particle diameter and magnetic field intensity on the zone are analyzed and discussed. A correlation to determine the stable fluidization zone is derived from the experimental data, using three dimensionless numbers, i. e., the ratio of magnetic potential to gravity potential, the Reynolds number and the Archimedes number. Compared with available data reported, it is shown that the correlation is more simplified to predict relative parameters for the bed operating in the state of stable fluidization under reasonable conditions.
基金Supported by the National Natural Science Foundation of China (No.20206023) and SIN0PEC (No.X504029).
文摘Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients increased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.
基金supported by the National Natural Science Foundation of China (Nos. 51134022 and 51174203)the Key Project of Chinese National Programs for Fundamental Research and Development (No. 2012CB214904)+2 种基金the National Natural Science Foundation of China for Innovative Research Group (No. 50921002)the Natural Science Foundation of Jiangsu Province (No. BK2010002)the Fundamental Research Funds for the Central Universities (Nos. 2010QNB11 and 2010ZDP01A06)
文摘In order to study the settling mechanism of particles in an air-solid magnetically stabilized fluidized bed(MSFB) for separation,we carried out free settling and quasi-zero settling tests on the tracing particles.The results show that the main resistance forces as the tracing particles settled in an air-solid MSFB were motion resistance force and yield force.The motion resistance and yield forces greatly hindered the free settling of the particles by greatly decreasing the acceleration for settling process of the particles.The acceleration decreased from 3022.62 cm/s 2 to zero in 0.1 s,and in the end,the particles stopped in the air-solid MSFB.The yield force on particles increased with increasing the magnetic field intensity,resulting in decrease of the quasi-zero settling displacement.However,the yield force on particles decreased with increasing the fluidized air velocity,leading to increase of the quasi-zero settling displacement.When the structure and operating parameters of the air-solid MSFB were set up,the yield stress on particles stopped in an air-solid MSFB was a function of diameter and density of particles.The settling displacements of equal diameter particles increased with increasing their densities,and the settling displacements of equal density particles increased with increasing their diameters.
文摘This article introduces the solid acid catalyst for isobutene/butylenes alkylation, the HTS Ti/Si zeolite for ammonoxidation of cyclohexanone and the noncrystalline alloy catalyst and magnetically stabi- lized bed for hydrofining of caprolactam that were developed recently by SINOPEC Research Institute of Petroleum Processing (RIPP).
基金Financial provided by the National Key Research and Development Program of China (Grant No. 2017YFC0603001)the National Natural Science Foundation of China (Nos. 51734009 and 51704279)the Natural Science Foundation of Jiangsu Province (BK20170270)
文摘The mechanism of bolt support is an important topic in mining engineering and slope treatment. The artificial material and loading system were self-developed to study the influence of bedding cohesion and bolt number on the anchoring behavior of bedded rock mass. The results show that, both peak strength and elasticity modulus increase gradually with the increase of bedding cohesion and bolt number. The axial stress–strain curve of bedded rock mass under the reinforcement of bolts presents the features of strain-softening and secondary strengthening. Finally, anchoring behavior of bedded rock mass with different bolt numbers was simulated by using FLAC3 D numerical program and the results were compared with the experimental results. This study can provide certain bases to the stability control and support design of bedded rock mass in roadway.
文摘Acute coronary syndrome (ACS) refers to a spectrum of clinical presentations ranging from unstable angina to non-ST-segment elevation myocardial infarction (NSTEMI) to ST-segment elevation myocardial infarction (STEMI). Aortic dissection, intramural hematoma and penetrating atherosclerotic ulcer (PAU) are three major acute aortic syndromes (AAS).
文摘AIM: To investigate endoscopic and clinicopathologic characteristics of early gastric cancer (EGC) according to microsatellite instability phenotype. METHODS: Data were retrospectively collected from a single tertiary referral center. Of 981 EGC patients surgically treated between December 2003 and October 2007, 73 consecutive EGC patients with two or more microsatellite instability (MSI) mutation [high MSI (MSI-H)] and 146 consecutive EGC patients with one or no MSI mutation (non-MSI-H) were selected. The endoscopic and clinicopathologic features were compared between the MSI-H and non-MSI-H EGC groups.RESULTS: In terms of endoscopic characteristics, MSI-H EGCs more frequently presented with elevated pattern (OR 4.38, 95% Cl: 2.40-8.01, P 〈 0.001), moderate- to-severe atrophy in the surrounding mucosa (OR 1.91, 95% CI: 1.05-3.47, P = 0.033), antral location (OR 3.99, 95% CI: 2.12-7.52, P 〈 0.001) and synchronous le- sions, compared to non-MSI-H EGCs (OR 2.65, 95% CI: 1.16-6.07, P = 0.021). Other significant clinicopatholog- ic characteristics of MSI-H EGC included predominance of female sex (OR 2.77, 95% CI: 1.53-4.99, P 〈 0.001), older age (〉 70 years) (OR 3.30, 95% CI: 1.57-6.92, P = 0.002), better histologic differentiation (OR 2.35, 95% Cl: 1.27-4.34, P = 0.007), intestinal type by Lau- ren classification (OR 2.34, 95% CI: 1.15-4.76, P = 0.019), absence of a signet ring cell component (OR 2.44, 95% CI: 1.02-5.86, P = 0.046), presence of mu- cinous component (OR 5.06, 95% Cl: 1.27-20.17, P = 0.022), moderate-to-severe lymphoid stromal reaction (OR 3.95, 95% CI: 1.59-9.80, P = 0.003), and co-exist- ing underlying adenoma (OR 2.66, 95% CI: 1.43-4.95, P = 0.002). CONCLUSION: MSI-H EGC is associated with unique endoscopic and clinicopathologic characteristics includ- ing frequent presentation in protruded type, co-exist- ing underlying adenoma, and synchronous lesions.
文摘A new salty and sandy desert of ca 5 million ha has emerged on the exposed Aral Sea bed. Every year, 170-200 tons of salt and dust rise into the air and fall on the territory of the Republic of Karakalpakstan. A number of experiments have been cond.ucted in order to study the salt tolerance of plants and select drought- and salt-resistant plant species, which show a wide ecological range, to fix quick-sand dunes on the exposed Aral Sea bed. Among the studied species of Calligonum genus C. caput-medusae Schrenk was the most resistant to the saline solution. At the end of the vegetation experiment, the survivability of individuals constituted 44.1% at the concentration of 1.0% of sodium chloride. Artemisiaferganensis Krasch. ex Poljak. and Salsola richteri (Moq.) Kar. ex Litv. showed a good resistance to the concentration of saline solution as high as 150 ram, at which no dried plants were recorded. As the concentration grew to 300 mM, the survivability of Artemisiaferganensis dropped to 40.0% while 66.7 Salsola richteri individuals were developing successfully. An almost similar result was obtained during the experiment on Nitraria schoberi L.. The survivability ofKrascheninnikovia ewersmanniana (Stschegl. ex Losinsk.) Grub. individuals significantly decreased at the concentration of 200 mm (33.4%), while for Agropyron cristatum the concentration of 300 mm was threshold, at which the survivability of individuals was below 3.3%. The most resistant to the deflation of sands on the exposed bed were Salsola richteri and Calligonum caput-medusae, whose survivability on the sandy dunes was 17%-41%.
基金Supported by projects of Geological Exploration of Jilin Province(No.22201300111)Shanhou Gold Deposit of Laixi of Shandong Province(SDLX2012-3-28)
文摘The Qiangsheng gold deposit belongs to quartz vein type. The fluid inclusions consist of four types: aqueous single-phase inclusions, aqueous two-phase inclusions, carbonated two-phase inclusions and carbona- ted three-phase inclusions. The fluid inclusions are characterized by low salinity (5%-9% NaCl eqv) , low density (0.66-0.72 g/cm^3 ) and medium temperature (210℃-250℃). The pressure of ore-forming is 60-95 MPa and the metallogenic depth is about 5.49-7.56 km. During the mineralizing process, ore-forming fluid under- went fluid unmixing in CO2-H2O-NaCl system. The stable isotope resuhs indicate that the ore-forming fluids mainly generated from mantle, with the participation of a small amount of atmospheric water. Comprehensive studies have suggested that Qiangsheng gold deposit belongs to the type of mesothermal hydrotherm with mantlederived fluid participating in mineralization.
文摘Sponsored by NSFC, a research team led by Prof. Enze Min (CAS Member) from Research Institute of Petroleum Processing, through 20 years' effort, settled the puzzled grave issue that amorphous alloy material has small specific surface area and low thermal stability. At the same time, they developed magnetic stabilization bed. Their innovation in catalyst and reaction process and in their project - 'catalytic chemistry
基金financial support from the Special Funds of the National Natural Science Foundation of China(21127011)National High Technology Research and Development Program of China(2011AA050606)National Natural Science Foundation of China(Petrochemical Joint Fund,U1162106)
文摘The present study reports a highly selective and stable catalytic approach for producing tetralin, an important chemical, solvent, and H2 storage material. Transition metal phosphides (MOP, Ni2P, Co2P, and Fe2P) were prepared by wet impregnation and temperature-programmed reduction and characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), EDX mapping, scanning electron microscopy (SEM), transmission electron microscopy (TEM), brunauer-emmett- teller (BET), temperature-programmed desorption of ammonia (NH3-TPD), and fourier transform infrared spectroscopy of pyridine (pyridine-FTIR). Of all the transition metal phosphides MoP was formed at a lower reduction temperature, which resuited in smaller particle size that enhanced the overall surface area of the catalyst. The existence of weak, moderate, and Lewis acidic sites over MoP were responsible for its high tetralin selectivity (90%) and stability during the 100 h reaction on-stream in a fixed-bed reactor.