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Comparative study on phase transition behaviors of fractional molecular field theory and random-site Ising model
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作者 刘婷玉 赵薇 +3 位作者 王涛 安小冬 卫来 黄以能 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期536-541,共6页
Fractional molecular field theory(FMFT)is a phenomenological theory that describes phase transitions in crystals with randomly distributed components,such as the relaxor-ferroelectrics and spin glasses.In order to ver... Fractional molecular field theory(FMFT)is a phenomenological theory that describes phase transitions in crystals with randomly distributed components,such as the relaxor-ferroelectrics and spin glasses.In order to verify the feasibility of this theory,this paper fits it to the Monte Carlo simulations of specific heat and susceptibility versus temperature of two-dimensional(2D)random-site Ising model(2D-RSIM).The results indicate that the FMFT deviates from the 2D-RSIM significantly.The main reason for the deviation is that the 2D-RSIM is a typical system of component random distribution,where the real order parameter is spatially heterogeneous and has no symmetry of space translation,but the basic assumption of FMFT means that the parameter is spatially uniform and has symmetry of space translation. 展开更多
关键词 phase transition molecular field theory Ising model Monte Carlo
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PREDICTION OF THE PHASE BEHAVIOR OF GAS CONDENSATES USING PATEL-TEJA EQUATION OF STATE AND GAMMA DISTRIBUTION FUNCTION 被引量:1
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作者 郑大庆 郭天民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1997年第3期12-19,共8页
The three-parameter Petal-Teja equation of state coupled with a characterization proceduref0r C<sub>7+</sub>-fraction based on gamma distribution function was employed to predict the phase behaviorof eight... The three-parameter Petal-Teja equation of state coupled with a characterization proceduref0r C<sub>7+</sub>-fraction based on gamma distribution function was employed to predict the phase behaviorof eight gas condensates.The lumping of the subdivided single carbon number(SCN)hydrocarbons inthe plus-fraction and the choice of empirical correlations for calculating the critical properties andacentric factor of SCN hydrocarbons were discussed. 展开更多
关键词 gas CONDENSATES phase BEHAVIOR EQUATION of state PREDICTION characterization of plus-fraction
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Phase Separation and Microstructure of Mixed Surfactants Solution Containing Cationic Geminis and Traditional Anionic Surfactant 被引量:2
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作者 尚亚卓 刘洪来 胡英 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期486-492,共7页
The properties of aqueous two-phase system (ATPS) of mixed solution containing gemini cationic surfactant trimethylene-1,3-bis(dodecyldimethyl ammonium) bromide (12-3-12, 2Br-) and traditional anionic surfactant sodiu... The properties of aqueous two-phase system (ATPS) of mixed solution containing gemini cationic surfactant trimethylene-1,3-bis(dodecyldimethyl ammonium) bromide (12-3-12, 2Br-) and traditional anionic surfactant sodium dodecyl sulfate (SDS) with or without added salt have been studied. An ATPS is formed in a narrow region of the ternary phase diagram different from that of traditional aqueous cationic-anionic surfactant systems. In ATPS region, the lowest total concentration of surfactants varies with the mixing ratio of geminis to SDS. Photographs obtained from freeze-etching, negative-staining and transmission electron microscopy show that the microstructures of two phases are different from each other. Micelles and vesicles can coexist in a single phase. The addition of salts can change the phase diagram of ATPS. Furthermore, the added salts promote the aggregation of rod-like micelles to form coarse network structure that increase the viscosity of solutions. The negative ions of the added salts are the determining factor. 展开更多
关键词 cationic gemini surfactant anionic surfactant aqueous two-phase system MICROSTRUCTURE
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A NOVEL PHASE CONTROL TECHNIQUE FOR INJECTION LOCKED OSCILLATORS
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作者 Kwok-Wai Wong Albert K. Y. Lai 曾学刚 《Journal of Electronics(China)》 1995年第4期374-377,共4页
A novel technique to obtain injection locked oscillators phase tuning beyond 180° is demonstrated. The idea is to cascade injection locked oscillators together for phase change accumulation. A two stage injection... A novel technique to obtain injection locked oscillators phase tuning beyond 180° is demonstrated. The idea is to cascade injection locked oscillators together for phase change accumulation. A two stage injection locked oscillators can theoretically provide a maximum of 360?phase change within the locking range. This is particularly useful for phased array antenna applications. 展开更多
关键词 PHASE CONTROL LOCKING Oscillators ANTENNA ARRAY
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Capillary Phase-Transition and Self-Diffusion of Ethylene in the Slit Carbon Pores
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作者 刘涛 刘洪来 袁渭康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期515-520,共6页
The grand canonical Monte Carlo (GCMC), the canonical Monte Carlo by using equal probability perturbation, and the molecular dynamics (MD) methods were used to study the capillary phase-transition (capillary condensat... The grand canonical Monte Carlo (GCMC), the canonical Monte Carlo by using equal probability perturbation, and the molecular dynamics (MD) methods were used to study the capillary phase-transition (capillary condensation and evaporation) and self-diffusion for a simple Lennard-Jones model of ethylene confined in slit carbon pores of 2.109 nm at temperatures between 141.26 K and 201.80 K. The critical point of capillary phase-transition was extrapolated by the critical power law and the law of rectilinear diameter from the capillary phase-transition data in the near critical region. The effects of temperature and fluid density on the parallel self-diffusion coefficients of ethylene molecules confined in the slit carbon pores were examined. The results showed that the parallel selfdiffusion coefficients in the capillary phase transition area strongly depended on the fluids local densities in the slit carbon pores. 展开更多
关键词 capillary phase-transition SELF-DIFFUSION
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Vapor-hydrate phases equilibrium of (CH_4+C_2H_6) and (CH_4+C_2H_4) systems 被引量:4
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作者 Ma Qinglan Chen Guangjin Zhang Lingwei 《Petroleum Science》 SCIE CAS CSCD 2008年第4期359-366,共8页
Separation of the (C1 + C2) hydrocarbon system is of importance in natural gas processing and ethylene production. However it is the bottleneck because of its high refrigeration energy consumption, and needs to be ... Separation of the (C1 + C2) hydrocarbon system is of importance in natural gas processing and ethylene production. However it is the bottleneck because of its high refrigeration energy consumption, and needs to be urgently addressed. The technology of separating gas mixtures by forming hydrate could be used to separate (C1 + C2) gas mixtures at around 0℃ and has attracted increasing attention worldwide. In this paper, investigation of vapor-hydrate two-phase equilibrium was carried out for (C1 + C2) systems with and without tetrahydrofuran (THF). The compositions of vapor and hydrate phases under phase equilibrium were studied with model algorithm when structure Ⅰ and structure Ⅱ hydrates coexisted for the (methane + ethane) system. The average deviation between the modeled and actual mole fractions of ethane in hydrate and vapor phases was 0.55%, and that of ethylene was 5.7% when THF was not added. The average deviation of the mole fraction of ethane in vapor phase was 11.46% and ethylene was 7.38% when THF was added. The test results showed that the proposed algorithm is practicable. 展开更多
关键词 Chen-Guo model vapor-hydrate equilibrium gas separation
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Kinetic and Phase Behaviors of Catalytic Cracking Dry Gas Hydrate in Water-in-Oil Emulsion 被引量:1
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作者 马庆兰 黄强 +3 位作者 陈光进 王秀林 孙长宇 杨兰英 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第3期295-300,共6页
The systematic experimental studies were performed on the hydrate formation kinetics and gas-hydrate equilibrium for a simulated catalytic cracking gas in the water-in-oil emulsion. The effect of temperature, pressure... The systematic experimental studies were performed on the hydrate formation kinetics and gas-hydrate equilibrium for a simulated catalytic cracking gas in the water-in-oil emulsion. The effect of temperature, pressure and initial gas-liquid ratio on the hydrate formation was studied, respectively. The data were obtained at pressures ranging from 3.5 to 5 MPa and temperatur.es from 274.15 to 277.15 K. The results showed that hydrogen and methane can be separated Irom the (~2+ ti'action by tOrming hydrate at around 273.15 K which is much higher temperature than that of the cryogenic separation method, and the hydrate formation rate can be enhanced in the wa- ter-in-oil emulsion compared to pure water. The experiments provided the basic data for designing the industrial process, and setting the suitable operational conditions. The measured data ot gas-hydrate equilibria were compared with the predictions by using the Chen-Guo hydrate thermodynamic model. 展开更多
关键词 HYDRATE catalytic cracking dry gas SEPARATION EMULSION
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A New Model of Ferroelectric Phase Transition with Neglectable Tunneling Effect
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作者 Hong-Mei Yin Heng-Wei Zhou Yi-Neng Huang 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第7期14-18,共5页
Due to the obvious deviations of the existing theoretical models from the experimental results of ferroelectric phase transition, a new model is proposed on the basis of the coupling between spontaneous polarization a... Due to the obvious deviations of the existing theoretical models from the experimental results of ferroelectric phase transition, a new model is proposed on the basis of the coupling between spontaneous polarization and spontaneous strain in ferroelectrics. The spontaneous polarization and specific heat of ferroelectric phase transition predicted by the model are in better agreement with the corresponding data of triglyceride sulfate, a typical ferroelectric.In addition, the model predicts a new type of ferroelectric in which a phase transition and a phase-like transition coexist. 展开更多
关键词 DUE to the obvious DEVIATIONS THEORETICAL MODELS TRANSITION coexist
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Highly efficient catalyzed by imidazolium-based dual-sulfonic acid functionalized ionic liquids for liquid phase Beckmann rearrangement:experiments and COSMO-RS calculations
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作者 Xin Guo Zhiyuan Wang +8 位作者 Ye Yang Jiahui Zhang Yanduo Liu Zhiyuan Mu Siqi Jiang Chunxiao Ren Dan Lv Yufeng Hu Zhichang Liu 《Green Chemical Engineering》 EI CSCD 2024年第1期108-118,共11页
A production technique with the high yield and environmentally friendly process need be developed forε-Caprolactam(CPL)in the chemical industry.This technology is highly desired to design and synthesize high--perform... A production technique with the high yield and environmentally friendly process need be developed forε-Caprolactam(CPL)in the chemical industry.This technology is highly desired to design and synthesize high--performance catalysts for liquid phase Beckmann rearrangement of cyclohexanone oxime(CHO)to CPL.In this work,3-methyl-1-(propyl-4-sulfonyl)imidazolium methanesulfonate([PHSO_(3)MIM][MSA])with highly efficient and excellent yield is synthesized successfully.When the optimum molar ratio of ZnCl_(2)over[PHSO_(3)MIM][MSA]was 0.02,it exhibits the high selectivity(94%)of CPL at 90℃for 1 h.Interestingly,Fourier-transform infrared(FT-IR)investigations show that the functional Br∅nsted-Lewis acidic types of ionic liquids(ILs)are formed by the uniformly distributed ZnCl_(2)and[PHSO_(3)MIM][MSA].In addition,the hydrogen bond(H-bond)is formed between CHO and ILs.After ten reaction cycles,no significant structure changes are observed in the recovered[PHSO_(3)MIM][MSA]-ZnCl_(2).The solubilities of ILs are predicted by using COSMO-RS model,the results show that[PHSO_(3)MIM][MSA]is a promising candidate for the liquid phase Beckmann rearrangement of CHO into CPL.Finally,a theoretical model of the H-bond interactions between ILs and CHO is further confirmed to support the advance of reaction mechanism.A feasible way is provided for the CPL production technique in the liquid phase Beckmann rearrangement reaction. 展开更多
关键词 Liquid phase Beckmann rearrangement Imidazolium-based ionic liquids COSMO-RS calculations H-BOND
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Subcutaneous daratumumab in Chinese patients with relapsed or refractory multiple myeloma:an open-label,multicenter,phase 1 study(MMY1010)
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作者 Gang An Zheng Ge +13 位作者 Hongmei Jing Jing Liu Guoping Yang Ru Feng Zhongyuan Xu Ming Qi Jianping Wang Juanjuan Song Wei Zhou Binbin Sun Dian Zhu Xi Chen Canchan Cui Lugui Qiu 《Blood Science》 2024年第3期42-47,共6页
Despite recent progress in multiple myeloma(MM)treatments,most patients will relapse and require additional treatment.Intravenous daratumumab,a human IgGκmonoclonal antibody targeting CD38,has shown good efficacy in ... Despite recent progress in multiple myeloma(MM)treatments,most patients will relapse and require additional treatment.Intravenous daratumumab,a human IgGκmonoclonal antibody targeting CD38,has shown good efficacy in the treatment of MM.A subcutaneous version of daratumumab was formulated to reduce the burden of intravenous infusions.We aimed to investigate the efficacy and safety of subcutaneous daratumumab in Chinese patients with relapsed/refractory MM based on the demonstrated noninferiority of subcutaneous daratumumab to intravenous daratumumab,with a shorter administration time and reduced infusion-related reaction rate in global studies.This phase 1,multicenter study(MMY1010;ClinicalTrials.gov Identifier:NCT04121260)evaluated subcutaneous daratumumab in Chinese patients with relapsed/refractory MM after 1 prior line(n=1)or≥2 prior lines(n=20)of therapy,including a proteasome inhibitor and an immunomodulatory drug.Primary endpoints were pharmacokinetics and safety.Mean(standard deviation)maximum trough concentration of daratumumab was 826(335)μg/mL,which was consistent with prior studies of subcutaneous daratumumab and intravenous daratumumab.Safety was consistent with safety profiles observed in other daratumumab studies,with no new safety concerns identified.Incidences of infusion-related reactions and injection-site reactions were low and consistent with other subcutaneous daratumumab studies.At a median follow-up of 7.5 months,the overall response rate was 57.1%,with a very good partial response or better rate of 38.1%and complete response or better rate of 19.0%.Our results demonstrate a favorable benefit/risk profile of subcutaneous daratumumab in Chinese patients with relapsed/refractory MM,potentially impacting clinical administration of daratumumab in this population. 展开更多
关键词 Chinese Daratumumab Multiple myeloma PHARMACOKINETIC Relapse/refractory Safety SUBCUTANEOUS
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SHR-A1811(antibody-drug conjugate)in advanced HER2-mutant non-small cell lung cancer:a multicenter,open-label,phase 1/2 study
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作者 Ziming Li Zhengbo Song +14 位作者 Wei Hong Nong Yang Yongsheng Wang Hong Jian Zibin Liang Sheng Hu Min Peng Yan Yu Yan Wang Zicong Jiao Kaijing Zhao Ke Song You Li Wei Shi Shun Lu 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2024年第8期3483-3492,共10页
A dose-escalation and expansion,phase 1/2 study(ClinicalTrials.gov,NCT04818333)was conducted to assess the novel antibodydrug conjugate SHR-A1811 in pretreated HER2-altered advanced non-small cell lung cancer(NSCLC).H... A dose-escalation and expansion,phase 1/2 study(ClinicalTrials.gov,NCT04818333)was conducted to assess the novel antibodydrug conjugate SHR-A1811 in pretreated HER2-altered advanced non-small cell lung cancer(NSCLC).Here,we report results from the phase 1 portion.Patients who had previously failed or were intolerant to platinum-based chemotherapy were enrolled and received SHR-A1811 intravenously at doses of 3.2 to 8.0 mg/kg every 3 weeks.Dose escalation followed a Bayesian logistic regression model that included overdose control,with subsequent selection of tolerable levels for dose expansion.Overall,63 patients were enrolled,including 43 receiving a recommended dose for expansion of 4.8 mg/kg.All patients had HER2-mutant disease.Dose-limiting toxicity occurred in one patient in the 8.0 mg/kg dose cohort.Grade≥3 treatment-related adverse events occurred in 29(46.0%)patients.One patient in the 6.4 mg/kg cohort died due to interstitial lung disease.As of April 11,2023,the 4.8 mg/kg cohort showed an objective response rate of 41.9%(95%Cl 27.0-57.9),and a disease control rate of 95.3%(95%Cl 84.2-99.4).The median duration of response was 13.7 months,with 13 of 18 responses ongoing.The median progression-free survival was 8.4 months(95%CI 7.1-15.0).SHR-A1811 demonstrated favourable safety and clinically meaningful efficacy in pretreated advanced HER2-mutantNSCLC. 展开更多
关键词 SHR HER2 doses
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Safety and immunogenicity of a modified COVID-19 mRNA vaccine,SYS6006,as a fourth-dose booster following three doses of inactivated vaccines in healthy adults:an open-labeled Phase 1 trial 被引量:1
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作者 Yuzhou Gui Ye Cao +9 位作者 Jiajin He Chunyang Zhao Wei Zheng Ling Qian Jie Cheng Chengyin Yu Chen Yu Kun Lou Gangyi Liu Jingying Jia 《Life Metabolism》 2023年第3期49-58,共10页
The continuous emergence of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants led to a rapid decline in protection efficacy and neutralizing titers even after three doses of COVID-19 vaccines.Her... The continuous emergence of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants led to a rapid decline in protection efficacy and neutralizing titers even after three doses of COVID-19 vaccines.Here,we report an open-labeled Phase I clinical trial of a modified mRNA vaccine(SYS6006)as a fourth-dose booster in healthy adults.Eighteen eligible participants,who had completed three doses of inactivated COVID-19 vaccines,received a fourth boosting dose of SYS6006-20μg.Eighteen convalescent COVID-19 patients were enrolled for the collection of serum samples as a comparator of immunogenicity.The primary endpoint of this trial was titers of anti-receptor binding domain of spike glycoprotein(RBD)antibodies of the Omicron strain(BA.2 and BA.4/5)in serum;titers of neutralizing antibodies against pseudovirus of the Omicron strain(BA.2 and BA.4/5).The secondary endpoint was the incidence of adverse events within 30 days after the boosting.The exploratory endpoint was the cellular immune responses(interferon gamma,IFN-γ).This trial was registered with the Chinese Clinical Trial Registry website.No serious adverse events were reported within 30 days after vaccination.No Grade 3 fever or serious adverse event was reported in the SYS6006 group.Notably,SYS6006 elicited higher titers and longer increases in anti-RBD antibodies and neutralizing antibodies(>90 days)compared with the convalescent group(P<0.0001)against Omicron strain(BA.2 and BA.4/5).Besides,higher positive spots of T-cell-secreting IFN-γwere observed in the SYS6006 group than those in the convalescent group(P<0.05).These data demonstrated that SYS6006 was well tolerated and highly immunogenic,generating a stronger and more durable immune response against different variants of SARS-CoV-2. 展开更多
关键词 SARS-CoV-2 mRNA vaccine SYS6006 heterologous boosting clinical trial
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玄武岩-聚乙烯醇纤维对再生混凝土抗冻性能的影响 被引量:2
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作者 司政 田爽 +3 位作者 皇甫秉辉 黄灵芝 杜晓奇 张飞跃 《长江科学院院报》 CSCD 北大核心 2024年第4期187-193,共7页
为了推广再生混凝土在高海拔和北方寒冷地区的应用,对单掺、混掺不同体积掺量玄武岩纤维和聚乙烯醇纤维的再生混凝土进行质量损失率、相对动弹性模量、抗压强度损失率3项抗冻性能指标的探究,并用SEM对200次冻融循环后混掺纤维再生混凝... 为了推广再生混凝土在高海拔和北方寒冷地区的应用,对单掺、混掺不同体积掺量玄武岩纤维和聚乙烯醇纤维的再生混凝土进行质量损失率、相对动弹性模量、抗压强度损失率3项抗冻性能指标的探究,并用SEM对200次冻融循环后混掺纤维再生混凝土进行细观作用机理分析,最后结合响应面法对混掺纤维掺量进行优选。结果显示:外掺纤维能够提高再生混凝土的抗冻性能,而混掺纤维效果优于单掺纤维;2种纤维在试件内部呈网状分布,协同受力,与基体互相约束,很大程度限制了裂缝的扩展和数量;纤维优化结果显示当聚乙烯醇纤维与玄武岩体积掺量分别为0.170%和0.246%时,再生混凝土的抗冻性能最优。研究成果对玄武岩-聚乙烯醇纤维再生混凝土纤维掺量设计具有一定的借鉴意义。 展开更多
关键词 再生混凝土 混掺纤维 纤维掺量优选 冻融循环 响应面法
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螺杆泵转速对油水旋流分离管流场特性的影响
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作者 赵立新 余帆 +3 位作者 徐保蕊 金宇 蒋明虎 卢梦媚 《石油机械》 北大核心 2024年第7期98-106,共9页
旋流分离器在井下采油螺杆泵作用下会发生复杂的振动现象,对旋流分离器内部流场造成一定影响。为研究螺杆泵不同转速下旋流分离器内部流场的变化规律,以同井注采工艺中螺杆泵作用下的旋流分离管柱为研究对象,针对振动壁面旋流分离管柱... 旋流分离器在井下采油螺杆泵作用下会发生复杂的振动现象,对旋流分离器内部流场造成一定影响。为研究螺杆泵不同转速下旋流分离器内部流场的变化规律,以同井注采工艺中螺杆泵作用下的旋流分离管柱为研究对象,针对振动壁面旋流分离管柱结构及工作特点,基于计算流体动力学方法、计算固体力学方法以及流固耦合理论,建立流固耦合力学模型;利用流固耦合分析方法,对双螺杆泵转动条件下井下旋流分离管柱内速度场、油相分布、涡量及湍动能等流场特性进行分析。分析结果表明:随着螺杆泵转速升高,分离器内切向速度和轴向速度强度逐渐减弱,径向速度的不对称性逐渐加剧,转速的周期性变化还会造成径向速度场分布的偏移;螺杆泵不同转速下旋流分离器内部涡量分布不同,随着转速升高,溢流管以及锥段部分附近相关流场的涡旋明显增强;旋流器溢流口附近油相体积分数会随着螺杆泵转速的升高而减小;不同螺杆泵转动状态下,大颗粒油滴的分布不同。所得结果可为螺杆泵井下旋流分离同井注采系统的设计及螺杆泵的转速设定提供参考。 展开更多
关键词 旋流分离管 油水分离 螺杆泵 流固耦合 流场分析 涡量 油相分布
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井下多级并联微旋流器流量均布性分析及优化
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作者 赵立新 罗华鑫 +1 位作者 刘琳 蒋明虎 《石油机械》 北大核心 2024年第9期81-88,共8页
采用多级并联微旋流器的方式实现井下油水分离,不仅可以提高采出液含油体积分数,同时能够满足高处理量要求。在井下工作时,若油水分离设备与套管间形成的油套环空流场结构不合理,会导致每级微旋流器组得到的流量不均匀,影响多级并联微... 采用多级并联微旋流器的方式实现井下油水分离,不仅可以提高采出液含油体积分数,同时能够满足高处理量要求。在井下工作时,若油水分离设备与套管间形成的油套环空流场结构不合理,会导致每级微旋流器组得到的流量不均匀,影响多级并联微旋流器分离装置的整体分离性能。基于数值模拟和响应面Box-Behnken试验设计方法,构建了分离装置和套管形成的油套环空流体域的结构参数与流量不均匀系数、最大压力损失间的数学模型,并对模型的有效性进行了验证。分析结果表明:当每级入口间距为400 mm、每级入口角度为90°、总级数为3级、出入口面积比为0.5时,优化后的流量不均匀系数从0.02653减小到0.01289,降幅达51.41%;与初始结构对比,当雷诺数在3000~8000范围内变化时,优化结构的流量不均匀系数在各种工况下比较稳定,最大可减小0.04708,最小为0.01125;优化后的结构呈现了较好的流量均匀分配性能及适应性。所得结果可为井下多级并联微旋流器的设计及应用提供参考。 展开更多
关键词 井下油水分离 多级并联 微旋油器 油套环空 流量均布 结构优化
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新型螺旋式气液旋流分离器数值模拟研究
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作者 魏松波 刘琳 +4 位作者 郑兴升 王新忠 鲁晓华 季豪 赵立新 《石油机械》 北大核心 2024年第8期132-140,共9页
为研究气液旋流分离器的气液分离性能,解决油气产出液中潜在高含气导致泵气锁的问题。基于旋流分离理论,设计了一种新型螺旋气液分离器。在不同气液比条件下对其内部流场进行研究。研究结果表明:随着分流比的增加,旋流器的内壁面和底流... 为研究气液旋流分离器的气液分离性能,解决油气产出液中潜在高含气导致泵气锁的问题。基于旋流分离理论,设计了一种新型螺旋气液分离器。在不同气液比条件下对其内部流场进行研究。研究结果表明:随着分流比的增加,旋流器的内壁面和底流口附近的含气体积分数显著降低,同时旋流器溢流压力损失逐渐增大,而底流压力损失逐渐减小,溢流压力损失增加的速率与底流压力损失减小的速率基本相同;分流比的增加使气液分离器的除气效率逐渐提高,底流含气体积分数逐渐减小。综合分析气液比分别为1∶1、1∶2、1∶5以及1∶8的4种工况,得出了其最佳溢流分流比分别为58%、39%、22%以及15%。研究结果可为高含气油井的井下气液分离装置设计提供依据,同时可为现场应用及操作提供指导。 展开更多
关键词 井下气液分离器 气液比 数值模拟 分离效率 溢流分流比
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倾斜管不同黏度气液两相段塞流持液率实验及预测方法
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作者 刘自龙 钱萧 +3 位作者 刘超 管桐 王伟 廖锐全 《特种油气藏》 CAS CSCD 北大核心 2024年第4期156-162,共7页
准确预测持液率可为井筒中的流型判断和压降预测提供重要依据,段塞流为稠油井筒中最常见流型,井筒高黏流体将加重气液两相滑脱,导致现有持液率模型应用于高黏流体的预测精度变差。为此,基于多相管流实验平台,在内径为60 mm的测试管段内... 准确预测持液率可为井筒中的流型判断和压降预测提供重要依据,段塞流为稠油井筒中最常见流型,井筒高黏流体将加重气液两相滑脱,导致现有持液率模型应用于高黏流体的预测精度变差。为此,基于多相管流实验平台,在内径为60 mm的测试管段内开展段塞流持液率实验,获取了不同黏度、不同倾角段塞流流型及持液率数据,研究了黏度对持液率和流型转变的影响规律,并结合实验现象和理论推导,提出了倾斜管不同黏度气液两相段塞流持液率新模型。研究结果表明:液相黏度的增加,会增加液相与管壁之间的黏滞力,导致持液率增加;黏度对持液率的影响会改变段塞流与其他流型的转变界限。以Kora液塞区持液率关系式为基础,建立了用混相黏度代替液相黏度的倾斜管气液两相段塞流持液率新模型,并利用实验数据和文献数据进行了验证,证实新模型具有更高的精度。该研究可为预测稠油井井筒压降提供技术支持。 展开更多
关键词 段塞流 持液率 气液两相流 倾斜管 稠油
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信息化管理在颜面部激光美容治疗中的应用及对患者认知偏差与期望水平的影响
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作者 杨雪 刘畅 《中国美容医学》 CAS 2024年第5期149-153,共5页
目的:分析信息化管理在颜面部激光美容治疗中的应用效果,并探究其对颜面部激光美容治疗患者的认知偏差与期望水平的影响。方法:回顾性分析2021年6月-2022年6月于笔者医院接受颜面部激光美容治疗的患者220例,依据管理方法不同进行分组,... 目的:分析信息化管理在颜面部激光美容治疗中的应用效果,并探究其对颜面部激光美容治疗患者的认知偏差与期望水平的影响。方法:回顾性分析2021年6月-2022年6月于笔者医院接受颜面部激光美容治疗的患者220例,依据管理方法不同进行分组,其中对照组(n=104)为2021年6月-2021年12月收治的采取常规管理的患者,观察组(n=116)为2022年1月-2022年6月收治的采取信息化管理的患者,比较两组患者的自我效能、应对方式、负性情绪、满意度及期望偏差,统计两组患者的不良反应发生率。结果:管理后,两组自我效能感量表(General self-efficacy scale,GSES)评分均升高,且观察组高于对照组(P<0.05);两组简易应对方式问卷(Simplified coping style questionnaire,SCSQ)积极应对评分均升高,且观察组高于对照组(P<0.05);SCSQ消极应对评分均降低,且观察组低于对照组(P<0.05)。管理后,两组(Body image rating scale,BIRS)以及凯斯勒心理困扰量表(The kessler psychological distress scale,K10)评分均降低,且观察组低于对照组(P<0.05)。管理后,观察组总满意率(88.79%)高于对照组(77.88%)(P<0.05)。管理后,观察组和对照组患者对手术期望过高、认为手术设计方案存在偏差占比分别为5.17%、6.03%和18.27%、3.85%,两组患者期望偏差率比较,差异有统计学意义(P<0.05)。观察组不良反应发生率(9.48%)低于对照组(19.23%)(P<0.05)。结论:信息化管理有利于减小颜面部激光美容治疗患者的认知偏差、恢复患者的正常期望水平,同时有效改善患者的负性情绪以及自我效能感,也提高了患者的满意度。 展开更多
关键词 信息化管理 颜面部激光美容 认知偏差 期望水平 自我效能感
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国产枸橼酸托法替布片的药动学及生物等效性研究
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作者 鲁萍 王杰 +2 位作者 尹小丽 张顺芝 吴蔚 《医药导报》 北大核心 2024年第2期203-207,共5页
目的通过探讨2种枸橼酸托法替布片在健康人群中的药动学特征,评价其生物等效性和安全性。方法采用随机、两周期、自身交叉设计,空腹/餐后各纳入36例受试者,每周期分别服用枸橼酸托法替布片(T或R)5 mg各1片,采用液相色谱-串联质谱(LC-MS/... 目的通过探讨2种枸橼酸托法替布片在健康人群中的药动学特征,评价其生物等效性和安全性。方法采用随机、两周期、自身交叉设计,空腹/餐后各纳入36例受试者,每周期分别服用枸橼酸托法替布片(T或R)5 mg各1片,采用液相色谱-串联质谱(LC-MS/MS)法检测血浆中托法替布片的浓度,Phoenix WinNonlin软件进行分析,计算药动学参数,评价其生物等效性。结果受试者单次口服T和R后,空腹组托法替布的主要药动学参数血药峰浓度(C_(max))分别为(57.54±13.95)、(59.17±12.31)ng·mL^(-1);浓度-时间曲线下面积(AUC_(0-t))分别为(143.83±34.58),(142.13±33.00)ng·h·mL^(-1);AUC_(0-∞)分别为(147.39±35.27)、(146.15±34.64)ng·h·mL^(-1);达峰时间(t_(max))均为0.50 h,餐后组托法替布的主要药动学参数C_(max)分别为(57.16±17.56)、(55.19±21.98)ng·mL^(-1);AUC_(0-t)分别为(165.47±41.63)、(162.04±41.84)ng·h·mL^(-1);AUC_(0-∞)分别为(171.88±44.15)、(168.05±44.21)ng·h·mL^(-1);t_(max)均为1.0 h,两制剂空腹组和餐后组C_(max)、AUC_(0-t)、AUC_(0-∞)几何均值比的90%置信区间分别为96.35%(90.11%~103.03%)和105.91%(95.20%~117.83%)、101.02%(98.76%~103.34%)和102.23%(99.67%~104.86%)、100.77%(98.53%~103.06%)和102.40%(99.81%~105.06%),均在80.00%~125.00%内。结论2种枸橼酸托法替布片在中国健康人群中生物等效,并且安全性良好。 展开更多
关键词 枸橼酸托法替布片 药动学 生物等效
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黄河流域九省(区)人口-水资源-经济-生态环境系统耦合协调发展及障碍因素分析 被引量:1
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作者 李佳璐 潘景茹 +2 位作者 冯峰 徐鹏 刘翠 《水资源与水工程学报》 CSCD 北大核心 2024年第1期47-56,共10页
黄河流域九省(区)人口扩张和经济发展带来一系列资源和环境问题,亟待探究其人口-水资源-经济-生态环境(PWEE)系统耦合协调关系,促进黄河流域高质量发展。针对黄河流域九省(区)构建了PWEE系统耦合协调发展评价指标体系,采用熵权法、耦合... 黄河流域九省(区)人口扩张和经济发展带来一系列资源和环境问题,亟待探究其人口-水资源-经济-生态环境(PWEE)系统耦合协调关系,促进黄河流域高质量发展。针对黄河流域九省(区)构建了PWEE系统耦合协调发展评价指标体系,采用熵权法、耦合协调度模型和障碍度模型,对2008—2020年黄河流域九省(区)PWEE系统综合发展水平、耦合协调状态和障碍因素进行分析。结果表明:黄河流域九省(区)PWEE系统及其各子系统综合发展水平呈上升趋势,耦合协调度从2008年的0.56上升至2020年的0.69,由勉强协调进入初级协调阶段,水资源子系统一直是影响九省(区)PWEE系统协调发展的限制因素,其平均障碍度从2008年的49.05%增加至2020年的55.48%,人均水资源量为主要障碍因子。 展开更多
关键词 人口-水资源-经济-生态环境系统 耦合协调度 障碍因素 黄河流域
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