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Preliminary Study on the Vaporization Ratio of the Slurry in the Residue Fluid Catalytic Cracking Disengager 被引量:5
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作者 闫平祥 蓝兴英 +1 位作者 徐春明 高金森 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期315-319,共5页
The vaporization ratios of the slurry at various temperature and partial pressure were calculated with the group-contribution method,and then the phase state of the slurry in the residue fluid catalytic cracking(RFCC)... The vaporization ratios of the slurry at various temperature and partial pressure were calculated with the group-contribution method,and then the phase state of the slurry in the residue fluid catalytic cracking(RFCC) disengager was determined.This research could provide some advices on how to select the technological conditions to decrease the coking in the RFCC disengager.The oil gas temperature and the slurry partial pressure had signifi- cant effects on the vaporization ratio of the slurry.Increasing the oil gas temperature and reducing the slurry partial pressure could effectively slow down the coking speed in the RFCC disengager.According to the calculation results, a correlation was established to predict the vaporization ratio of the slurry under different operating conditions. 展开更多
关键词 DISENGAGER SLURRY group-contribution method vaporization ratio correlation model
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In Vitro Study on the Vaporization Ratio of 2-μm Laser in Human Prostatic Tissue
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作者 杨勇 孙东翀 +3 位作者 魏志涛 徐锋 洪宝发 张旭 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第2期198-200,共3页
In this study, the vaporization ratio of the 2-μm laser in the prostatic tissue with benign prostatic hyperplasia was examined in vitro, to explore a technique to estimate the clearance rate of prostatic tissue durin... In this study, the vaporization ratio of the 2-μm laser in the prostatic tissue with benign prostatic hyperplasia was examined in vitro, to explore a technique to estimate the clearance rate of prostatic tissue during the transurethral vaporesection of the prostate. A total of 9 fresh prostatic tissue specimens were obtained by open surgery and the wet weight of the prostatic tissue were measured immediately after the sample collection. Under the simulated conditions of transurethral vaporesection of the prostate by 2-μm laser, each prostate gland was completely vaporesected into fragments with a diameter of less than 1.0 cm in vitro tissue were collected and measured. Then After the vaporesection, the whole fragments of prostatic the lost weight of prostatic tissue, the weight of the collected prostatic tissue and the ratio of the lost weight of prostatic tissue to the wet weight of the prostate glandular organ specimen were calculated. The correlation between the weight of collected prostatic tissue and the weight of the whole glandular organ was analyzed. All the experimental procedures were carried out by one operator. Wet weight of the prostatic gland specimen and the weight of the harvested prostatic tissues after the procedure were recorded. With respect to the wet weight of prostate gland specimen, the percentage of the weight of collected prostatic tissue was (34.45±1.51) %, and the percentage of the lost weight of prostatic tissue was (65.55±1.51)%. Satisfactory linear relationship was observed between the weight of collected prostatic tissue and the wet weight of prostate gland specimen [y=3.245x=6.475 (t=15.097, P=0.000)]. It is concluded that under the simulated conditions of transurethral vaporesection of the prostate by 2-μm laser, the vaporization ratio of prostatic tissue can be calculated on the basis of the weight of collected prostatic tissue, and thereby the clearance of prostatic tissue during the formal operation by 2-μm laser could be quantitatively determined. 展开更多
关键词 2-μm laser benign prostatic hyperplasia vaporIZATION ratio
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THE MIXING OF GAS-LIQUID FLOW WITH VAPOR AND GAS-SOLID FLOW
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作者 林多敏 蔡树棠 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第6期513-518,共6页
In the industrial production, the mixing of gas-liquid flow with vapor and gas-solid flow is a very common problem. In the process of the mixing, solid particle-clusters will form, and will have steady radii when the ... In the industrial production, the mixing of gas-liquid flow with vapor and gas-solid flow is a very common problem. In the process of the mixing, solid particle-clusters will form, and will have steady radii when the effect of the gathering of particles is balanced withthat of the breaking of particle-clusters. Then, the population distribution function of size of particles per unit length per unit volume is introduced, and its governingequation is derived on the analogy of the molecular kinetic theory. Finally, when the gas flow is very slow, the expression of steady average radius of particle-clusters is obtained. 展开更多
关键词 the mixing of GAS-LIQUID FLOW WITH vapor AND GAS-SOLID FLOW GAS
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Biohydrogen Production from Synthetic Waste Co-digested with Liquid Dairy Cow Manure: Effect of Temperature and Mixing Ratio
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作者 S. A. Lateef T. Yamashiro N. Beneragama M. Iwasaki Y. Moriya C. Ying K. Umetsu 《Journal of Agricultural Science and Technology(A)》 2011年第8期1303-1306,共4页
Biohydrogen production from synthetic waste, SW (model organic fraction of municipal solid waste) co-digested with liquid dairy manure (M) was tested in batch reactions to assess the effect of temperature and mixi... Biohydrogen production from synthetic waste, SW (model organic fraction of municipal solid waste) co-digested with liquid dairy manure (M) was tested in batch reactions to assess the effect of temperature and mixing ratio of the substrates. A 5 × 2 factorial design experiment was conducted. Synthetic waste: manure mixtures of 1:1, 2:1, 3:1, 1:0, 0:1 (volatile solids, VS, basis) were tested at 37 (T37) and 55 ℃ (T55) using thirty 1 L laboratory scale digesters. Total VS of each mixture was 50 g/L except SW:M 0:I treatment, where total VS was 27.4 g/L. Gas samples were taken daily to determine hydrogen production, and slurry samples taken before and after experimentation, were analyzed for volatile fatty acid (VFA) concentration, volatile solid (VS) degradation, ammonium nitrogen (NH4+-N) and pH. Hydrogen production (mL/g-VS fed) showed a significant two-factor interaction between incubation temperature and SW:M ratio (P 〈 0.001). Maximum production of 15.8 mL/g-VS (fed) was achieved in SW:M ratio of 3:1 at 55 ℃. Generally, hydrogen productions at thermophilic temperature (T55) were significantly higher than at mesophilic (T37) temperature for all treatments (P 〈 0.001) except for SW:M 1:0 and SW:M 0:1 treatments (P 〉 0.05). This study indicates that hydrogen production from co-digestion of synthetic waste and manure is dependent on incubation temperature and relative contribution of wastes in the mixture. 展开更多
关键词 Hydrogen production CO-DIGESTION TEMPERATURE mixing ratio dairy cow manure
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Variations of CO2 Mixing Ratios in the Air near the Ground in the European Territory of Russia
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作者 Felix Kashin 《Journal of Environmental Science and Engineering(A)》 2013年第9期531-536,共6页
The instrumentation, method and measurement results used for measurements of CO2 concentrations in surface air of Obninsk (55.1° N, 36.9° E, 183 m above the sea level) located at a distance of 105 km to th... The instrumentation, method and measurement results used for measurements of CO2 concentrations in surface air of Obninsk (55.1° N, 36.9° E, 183 m above the sea level) located at a distance of 105 km to the south-west of Moscow are presented. Proposed is a method of experimental data filtering allowing one to separate natural and anthropogenic variations of CO2 concentrations. It is shown that minimal concentrations of CO2 registered in Obninsk and at the continental stations of GAW WMO characterize not only the "regional background" but also coincide with the data from GAW WMO background stations located in the oceanic regions. In this connection, one can assume that the excess in measured CO2 concentration over its minimal values, making about 5-6 ppm, is connected with an anthropogenic emission, and the continent should be considered as an anthropogenic source of C02. 展开更多
关键词 Carbon dioxide mixing ratio natural and anthropogenic variations.
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Constraining Anthropogenic CH_4 Emissions in Nanjing and the Yangtze River Delta,China,Using Atmospheric CO_2 and CH_4 Mixing Ratios 被引量:7
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作者 SHEN Shuanghe YANG Dong +2 位作者 XIAO Wei LIU Shoudong Xuhui LEE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第6期1343-1352,共10页
Methane (CH4) emissions estimated with the Intergovernmental Panel on Climate Change (IPCC) inventory method at the city and regional scale are subject to large uncertainties.In this study,we determined the CH4:C... Methane (CH4) emissions estimated with the Intergovernmental Panel on Climate Change (IPCC) inventory method at the city and regional scale are subject to large uncertainties.In this study,we determined the CH4:CO2 emissions ratio for both Nanjing and the Yangtze River Delta (YRD),using the atmospheric CH4 and CO2 concentrations measured at a suburban site in Nanjing in the winter.The atmospheric estimate of the CH4:CO2 emissions ratio was in reasonable agreement with that calculated using the IPCC method for the YRD (within 20%),but was 200% greater for the municipality of Nanjing.The most likely reason for the discrepancy is that emissions from unmanaged landfills are omitted from the official statistics on garbage production. 展开更多
关键词 METHANE IPCC inventory atmospheric mixing ratio city region
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Effect of Starch/Polylactic Acid Ratio on the Interdependence of Two-Phase and the Properties of Composites 被引量:3
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作者 左迎峰 GU Jiyou +3 位作者 CAO Jun WEI Shuangying TAN Haiyan 张彦华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第5期1108-1114,共7页
Starch/polylactic acid(PLA) composites were prepared by melt extrusion, with corn starch and PLA as raw materials, glycerol as the plasticizer. Effects of starch/PLA ratio on the interdependence of two-phase and other... Starch/polylactic acid(PLA) composites were prepared by melt extrusion, with corn starch and PLA as raw materials, glycerol as the plasticizer. Effects of starch/PLA ratio on the interdependence of two-phase and other properties of the composites were studied. The combination of results of TGA with SEM indicated that the interdependence between starch and PLA was increased gradually as the starch/PLA ratio reduced. DSC results showed that the glass transition temperature(Tg), melting temperature(Tm) and degree of crystallinity of PLA in composites were increased gradually, whereas the cold crystallization temperature(Tc) was gradually decreased as the starch/PLA ratio reduced. The rheological properties of composites were closely related with the interdependence of two-phase, with reducing starch/PLA proportion, the interdependence was increased, and then the strain for storage modulus was firstl reduced and then gradually increased. Frequency scanning showed that the storage modulus and complex viscosity were decreased with reducing starch content. As the starch/PLA ratio reduced, the matrix phase PLA was increased, so that the strength of composites was increased gradually, whereas water absorption rate was decreased gradually. 展开更多
关键词 corn starch polylactic acid mixing ratio interdependence of two-phase PROPERTIES
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Numerical Investigation on Effect of Vapor Split Ratio to Performance and Operability for Dividing Wall Column 被引量:4
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作者 Laleh Torab Maralani 袁希钢 +2 位作者 罗祎青 龚超 余国琮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期72-78,共7页
Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed f... Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed for each case by optimizing the vapor split to the two sides of the dividing wall, and then their feasibilities and total annual costs in operation were evaluated against different vapor split ratios. The analysis on the operability of the DWC for four cases was made based on two scenarios: (1) vapor split is shifted by the vapor resistance difference between the column sections in the two sides of the dividing wall and (2) the feed composition is changed. It was demonstrated that the positioning of the dividing wall and the decision on the vapor split may affect significantly the operability of a DWC. 展开更多
关键词 dividing wall column vapor split ratio OPERABILITY
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O,H,and Sr isotope evidence for origin and mixing processes of the Gudui geothermal system,Himalayas,China 被引量:8
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作者 Chenguang Wang Mianping Zheng +4 位作者 Xuefei Zhang Enyuan Xing Jiangyi Zhang Jianhong Ren Yuan Ling 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第4期1175-1187,共13页
Tho Gudui geothermal field records the highest temperature at equivalent borehole depths among the lainland hydrothermal systems in China's Mainland.Located about 150 km southeast of Lhasa City,the capital of Tibe... Tho Gudui geothermal field records the highest temperature at equivalent borehole depths among the lainland hydrothermal systems in China's Mainland.Located about 150 km southeast of Lhasa City,the capital of Tibet,the Gudui geothermal field belongs to the Sangri-Cuona rift belt,also known as the Sangri-Cuona geothermal belt,and is representative of the non-volcanic geothermal systems in the Himalayas.In this study,oxygen-18 and deuterium isotope compositions as well as 87Sr/86Sr ratios of water samples collected from the Gudui geothermal field were characterized to understand the origin and mixing processes of the geothermal fluids at Gudui.Hydrogen and oxygen isotope plots show both,deep and shallow reservoirs in the Gudui geothermal field.Deep geothermal fluids are the mixing product of magmatic and infiltrating snow-melt water.Calculations show that the magma fluid component of the deep geothermal fluids account for about 21.10%-24.04%;magma fluids lay also be a contributing source of lithium.The linear relationship of the 87Sr/86Sr isotopic ratio versus the 1/Sr plot indicates that shallow geothermal fluids form from the mixing of deep geothermal fluids with cold groundwater.Using a binary mixing model with deep geothermal fluid and cold groundwater as two end-members,the nixing ratios of the latter in most surface hot springs samples were calculated to be between 5% and 10%.Combined with basic geological characteristics,hydrogen and oxygen isotope characteristics,strontium concentration,87Sr/(86)Sr ratios,and the binary mixing model,we infer the 6 th-Class Reservoirs Evolution Conceptual Model(6-CRECM) for the Gudui geothermal system.This model represents an idealized summary of the characteristics of the Gudui geothermal field based on our comprehensive understanding of the origin and mixing processes of the geothermal fluid in Gudui.This study may aid in identifying the geothermal and geochemical origin of the Gudui high-temperature hydrothermal systems in remote Tibet of China,whose potential for geothermal development and utilization is enormous and untapped. 展开更多
关键词 Geothermal fluid Oxygen-18 and deuterium isotope 87Sr/86Sr ratio Origin and mixing Gudui HIMALAYAS
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Prediction Model-based Multi-objective Optimization for Mix-ratio Design of Recycled Aggregate Concrete
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作者 CHEN Tao WU Di YAO Xiaojun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1507-1517,共11页
The prediction model for mechanical properties of RAC was established through the Bayesian optimization-based Gaussian process regression(BO-GPR)method,where the input variables in BO-GPR model depend on the mix ratio... The prediction model for mechanical properties of RAC was established through the Bayesian optimization-based Gaussian process regression(BO-GPR)method,where the input variables in BO-GPR model depend on the mix ratio of concrete.Then the compressive strength prediction model,the material cost,and environmental factors were simultaneously considered as objectives,while a multi-objective gray wolf optimization algorithm was developed for finding the optimal mix ratio.A total of 730 RAC datasets were used for training and testing the predication model,while the optimal design method for mix ratio was verified through RAC experiments.The experimental results show that the predicted,testing,and expected compressive strengths are nearly consistent,illustrating the effectiveness of the proposed method. 展开更多
关键词 recycled coarse aggregate mix ratio multi-objective optimization prediction model compressive strength
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Solution of the Nucleon Structure Problem from a Field Theory of Fermions and Bosons and the Origin of the Proton Stability
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作者 Hans-Peter Morsch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1655-1669,共15页
A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor r... A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor ratios μpGEp/GMpand μnGEn/GMn. A quantitative description is obtained, assuming a mixing of a scalar bound state of 3(f f¯)fstructure with its corresponding vector (f f¯)fstate (f indicating massless elementary fermions). Only a few parameters are needed, mainly fixed by energy and momentum conservation. The nucleon stability is explained by an extra binding in the confinement potential, negative for electric and positive for magnetic binding of the proton, and opposite for the neutron. The stronger electric extra binding of the proton allows a decay of the neutron to proton and electron. 展开更多
关键词 Proton and Neutron Properties Described in a New Bound State Formalism by a mixing of Two Related Bound States Quantitative Agreement with their Masses RADII Magnetic Moments and Electromagnetic Form Factor ratios High Stability Due to Extra Binding in the Confinement Potential
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ANTIMICROBIAL ACTIVITY OF COPOLYMERS OF 2,4-DICHLOROPHENYL ACRYLATE WITH STYRENE:SYNTHESIS,CHARACTERIZATION AND REACTIVITY RATIOS
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作者 Hetal J.Patel Mitesh G.Patel +2 位作者 Kirit H.Patel Arabinda K.Ray Rajni M.Patel 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第1期121-130,共10页
Some copolymers of 2,4-dichlorophenyl acrylate (2,4-DCPA) with styrene (St) of different teed compositions were prepared by tree radical polymerization technique using 2,2′-azobisisobutyronitrile (AIBN) as an initiat... Some copolymers of 2,4-dichlorophenyl acrylate (2,4-DCPA) with styrene (St) of different teed compositions were prepared by tree radical polymerization technique using 2,2′-azobisisobutyronitrile (AIBN) as an initiator,and the copolymers were characterized by IR spectroscopy.The copolymer composition obtained by UV-spectra led to determination of reactivity ratio by employing Fineman-Ross (F-R) and Kelen-Tudos (K-T) methods.Average molecular weight,as well as intrinsic viscosity,was obtained by vapor pressu... 展开更多
关键词 COPOLYMERS Reactivity ratios vapor pressure osmometry thermal analysis Antimicrobial screening
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Estimating the shareholder's terminal payoff based on insurer's solvency ratio in mixed fractional Brownian market
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作者 XIA Deng-feng FEI Wei-yin LIU Hong-jian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第3期317-324,共8页
This paper studies the insurer’s solvency ratio model in a class of mixed fractional Brownian motion(MFBM) market, where the prices of assets follow a Wick-It? stochastic differential equation driven by the MFBM, by ... This paper studies the insurer’s solvency ratio model in a class of mixed fractional Brownian motion(MFBM) market, where the prices of assets follow a Wick-It? stochastic differential equation driven by the MFBM, by the method of the stochastic calculus of the MFBM and the pricing formula of European call option for the MFBM, the explicit formula for the expected present value of shareholders’ terminal payoff is given. The model extends the existing results. 展开更多
关键词 mixed fractional Brownian motion Wick-It stochastic integral solvency ratio financial distress cost
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Optimization Analysis of the Mixing Chamber and Diffuser of Ejector Based on Fano Flow Model
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作者 Lixing Zheng Weibo Wang +2 位作者 Yiyan Zhang Lingmei Wang Wei Lu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第10期153-170,共18页
An improved model to calculate the length of the mixing chamber of the ejector was proposed on the basis of the Fano flow model,and a method to optimize the structures of the mixing chamber and diffuser of the ejector... An improved model to calculate the length of the mixing chamber of the ejector was proposed on the basis of the Fano flow model,and a method to optimize the structures of the mixing chamber and diffuser of the ejector was put forward.The accuracy of the model was verified by comparing the theoretical results calculated using the model to experimental data reported in literature.Variations in the length of the mixing chamber L_(m) and length of the diffuser L_(d) with respect to variations in the outlet temperature of the ejector T_(c),outlet pressure of the ejector p_(c),and the expansion ratio of the pressure of the primary flow to that of the secondary flow p_(g)/p_(e) were investigated.Moreover,variations in L_(m) and L_(d) with respect to variations in the ratio of the diameter of the throat of the motive nozzle to the diameter of the mixing chamber d_(g0)/d_(c3) and ratio of the outlet diameter of the diffuser to the diameter of themixing chamber d_(c)/d_(c3) were investigated.The distribution of flow fields in the ejector was simulated.Increasing L_(m) and d_(c3) reduced T_(c) and p_(c).Moreover,reducing p_(g)/p_(e) or d_(g0)/d_(c3) reduced T_(c) and p_(c).The length of the mixed section L_(m2),which was determined on the basis of the Fano flow model,increased as pg increased and decreased as d_(c3) increased.The mixing length L_(m1),which was considered the primary flow expansion,showed the opposite trend with that of L_(m2).Moreover,Ld increased as p_(g)/p_(e) and d_(c)/d_(c3) increased.When the value of d_(c) was 1.8 to 2.0 times as high as that of dc3,the semi-cone angle of the diffuser ranged between 6°and 12°.At a constant dc/dc3,decreasing T_(c) and pc increased Ld. 展开更多
关键词 mixing chamber LENGTH Fano flow DIFFUSER diameter ratio expansion ratio optimization method
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Measurements of NO_2 mixing ratios with topographic target light scattering-differential optical absorption spectroscopy system and comparisons to point monitoring technique
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作者 王杨 李昂 +6 位作者 谢品华 曾议 王瑞斌 陈浩 裴显 刘建国 刘文清 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期285-290,共6页
A topographic target light scattering-differential optical absorption spectroscopy ('IbTaL-DOA~) system is de- veloped for measuring average concentrations along a known optical path and studying surface-near distr... A topographic target light scattering-differential optical absorption spectroscopy ('IbTaL-DOA~) system is de- veloped for measuring average concentrations along a known optical path and studying surface-near distributions of atmospheric trace gases. The telescope of the ToTaL-DOAS system points to targets which are located at known dis- tances from the measurement device and illuminated by sunlight. Average concentrations with high spatial resolution can be retrieved by receiving sunlight reflected from the targets, A filed measurement of NO2 concentration is performed with the ToTaL-DOAS system in Shijiazhuang in the autumn of 2011. The measurement data are compared with con- centrations measured by the point monitoring technique at the same site. The results show that the ToTaL-DOAS system is sensitive to the variation of NO2 concentrations along the optical path. 展开更多
关键词 atmospheric optics target light scattering-differential optical absorption spectroscopy(ToTaL-DOAS) atmospheric trace gas averaging mixing ratio
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Experimental research on the mixed sand ratio and initial dry density of weathered sand improved expansive soil free load swelling rate
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作者 Yang Jun Yang Zhi +2 位作者 Zhang Guodong Tang Yunwei Chen Hongping 《Engineering Sciences》 EI 2014年第3期77-82,共6页
In this paper, through the indoor free load swelling rate test, expansive soil in a section of a first- class highway reconstruction project in Yichang City was studied. It emphatically analyzed the interrelations amo... In this paper, through the indoor free load swelling rate test, expansive soil in a section of a first- class highway reconstruction project in Yichang City was studied. It emphatically analyzed the interrelations among free load swelling rate, non-load time, the proportion of mixed sand and initial dry density. Experimen- tal studies have shown that: Free load swelling deformation is mainly divided into three stages of rapid expan- sion, slow expansion and final stability; when the initial dry density is constant, free load swelling rate of the weathered sand modified soil will reduce rapidly before they slow down with the increase of sand proportion, and weathered sand modified soil free load swelling rate is not sensitive to the large amount of sand mixed; in the same mixed sand ratio, weathered sand modified soil free load swelling rate increases rapidly with the in- crease of initial dry density, there is a good linear correlation between them. To take appropriate control of the initial dry density during the expansive soil subgrade construction helps to reduce its swelling deformation and ensures the stability of the embankment. 展开更多
关键词 expansive soil weathered SAND INITIAL DRY density mixing SAND ratio free LOAD SWELLING rate
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Effects of Lobe Peak-to-Trough Width Ratio on Mixing and Combustion Performance in ATR Combustors
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作者 ZHAO Qingjun ZHANG Yuankun +3 位作者 HU Bin WANG Zhonghao SHI Qiang ZHAO Wei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第6期637-650,共14页
The air-turbo-rocket(ATR)engine is a promising propulsion plant for achieving numerous surface and air launched missile missions.The application of lobed mixer in the ATR combustor can promote the mixing of the fuelri... The air-turbo-rocket(ATR)engine is a promising propulsion plant for achieving numerous surface and air launched missile missions.The application of lobed mixer in the ATR combustor can promote the mixing of the fuelrich gas and the air,thus improving the engine performance significantly.The numerical simulation method was conducted to explore the effects of lobe peak-to-trough width ratio on mixing and combustion performance in ATR combustors.Results show that:For a given peak lobe width b1,the combustion efficiency and total pressure loss decrease with the increase of trough lobe width b2;For a given b2,the combustion efficiency and total pressure loss decrease with the increase of b1;The fan-type lobed mixer with smaller b2has a better effect on promoting the combustion efficiency in the region near the ATR combustor center line than that with a pair of parallel side walls.The total pressure recovery coefficient reaches more than 0.99 at the exit of combustor in nonreactive combustion while the total pressure loss reaches more than 4%in the reacting combustion.Compared with the mixing process,more than80%of the total pressure loss is caused during combustion. 展开更多
关键词 ATR combustor lobed mixer lobe peak-to-trough width ratio mixing combustion streamwise vortex
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Equal Volumes of Sand and Gravel Concrete Mix Ratios in Cameroon and Its Effect on Concrete Compressive Strength
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作者 Patrick Bame Che Yamb Bell Emmanuel Ndigui Billong 《World Journal of Engineering and Technology》 2022年第3期539-549,共11页
In recent years, the rationalization of concrete mix ratios which batches equal volumes of sand and gravel in building projects has been gaining grounds in the Cameroon construction industry. The main objective of thi... In recent years, the rationalization of concrete mix ratios which batches equal volumes of sand and gravel in building projects has been gaining grounds in the Cameroon construction industry. The main objective of this study is therefore to investigate if the concrete produced with rationalized mix ratio can be adopted as conventional mix ratio in terms of minimum required compression strength of concrete for buildings. Specifically this work compared the conventional mix ratio of 350 kg of cement: 400 liters of sand: 800 liters of gravel for a cubic meter and the rationalized batch of 350 kg of cement: 600 liters of sand: 600 liters of 5/15 gravel, 15/25 gravel and a combination of 5/15 + 15/25 gravel. Average compressive tests’results for both the conventional and the rationalized mix ratios were found to meet the minimum compressive strength of 65% at 7 days, 90% at 14 days and 99% at 28 days for gravel size combination 5/15 + 15/25. Single size gravel of 5/15 and 15/25 did not meet the minimum required compressive strength of 20 N/mm<sup>2</sup> for the rationalized mix ratio at 28 days curing based on the minimum compressive strength required, this study arrives at the conclusion that the equal volumes of sand and gravel mix ratio of 350 kg/m<sup>3</sup> of cement: 600 liters of sand: 600 liters of gravel mix ratio can be adopted as a conventional concrete mix ratio for gravel size 5/15 + 15/25. 展开更多
关键词 Conventional Concrete rationalized Concrete Mix ratio Compressive Strength Equal volumes of Sand and Gravel
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A G^E/Equation of State Mixing Rule for Vapor-Liquid Equilibria
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作者 屈一新 汪文川 +5 位作者 Lee Y.Y. Chung K.Y. Lee Y.W. 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1998年第3期14-28,共15页
A new excess Gibbs free energy/equation of state type mixing 0rule was derived byremoving the infinite pressure boundary condition imposed by Wong and Sandler.The mixing rulewas extensively tested in terms of a compre... A new excess Gibbs free energy/equation of state type mixing 0rule was derived byremoving the infinite pressure boundary condition imposed by Wong and Sandler.The mixing rulewas extensively tested in terms of a comprehensive data base,consisting of 52 simple nonpolar-nonpolar,carbon dioxide containing,hydrocarbon-hydrocarbon,CFC,polar-polar,nonpolar-polarbinary and multicomponent systems.Focused on the complete predictive capability,a comparisonbetween the Wong-Sandler and the mixing rule proposed was conducted.The results indicate that thenew mixing rule is in general superior to the Wong-Sandler’s,and the binary interaction parameteras required by the latter is removed,which reduces computing effort and is reliable in predictions ofvapor-liquid equilibria from low pressures to high pressures. 展开更多
关键词 vapor-LIQUID EQUILIBRIA EQUATION of state mixing RULE
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Determination Multipole Mixing Ratios and Transition Strengths of Gamma Rays from Level Studies of 93Mo (p, nγ) Reaction
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作者 Mayyada M. Hamarashid 《Journal of Physical Science and Application》 2012年第7期253-257,共5页
The multipole mixing ratios have been calculated by a2-ratio method, from levels of 93Mo(p, nγ) reaction. The branching ratios of such γ-transitions are used to calculate the total gamma widths. Besides, the trans... The multipole mixing ratios have been calculated by a2-ratio method, from levels of 93Mo(p, nγ) reaction. The branching ratios of such γ-transitions are used to calculate the total gamma widths. Besides, the transition strengths and probabilities have been calculated for γ-transitions from excited states whose life times have been reported previously. The results are found to be in general in good agreement with the previous results populated from the previous work. 展开更多
关键词 Moltipole mixing ratio mean lifetime gamma widths transitions strength transitions probabilities.
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