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USTC-Pickers:a Unified Set of seismic phase pickers Transfer learned for China 被引量:3
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作者 Jun Zhu Zefeng Li Lihua Fang 《Earthquake Science》 2023年第2期95-112,共18页
Current popular deep learning seismic phase pickers like PhaseNet and EQTransformer suffer from performance drop in China.To mitigate this problem,we build a unified set of customized seismic phase pickers for differe... Current popular deep learning seismic phase pickers like PhaseNet and EQTransformer suffer from performance drop in China.To mitigate this problem,we build a unified set of customized seismic phase pickers for different levels of use in China.We first train a base picker with the recently released DiTing dataset using the same U-Net architecture as PhaseNet.This base picker significantly outperforms the original PhaseNet and is generally suitable for entire China.Then,using different subsets of the DiTing data,we fine-tune the base picker to better adapt to different regions.In total,we provide 5 pickers for major tectonic blocks in China,33 pickers for provincial-level administrative regions,and 2 special pickers for the Capital area and the China Seismic Experimental Site.These pickers show improved performance in respective regions which they are customized for.They can be either directly integrated into national or regional seismic network operation or used as base models for further refinement for specific datasets.We anticipate that this picker set will facilitate earthquake monitoring in China. 展开更多
关键词 phase picking transfer learning model customization
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Pregnancy outcomes following supplementation of single dose GnRH agonist to sustain the luteal phase in antagonist fresh embryo transfer cycles:A multicentric prospective cohort study
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作者 Tatapudi S V Parvathi Devi Alka Gahlot +3 位作者 Sangita Sharma Manisha Choudhary Ravikant Soni Meeta Sharma 《Asian pacific Journal of Reproduction》 2023年第4期162-169,共8页
Objective:To determine whether a single dose of gonadotropin-releasing hormone(GnRH)agonist administered subcutaneously in addition to the regular progesterone supplementation could provide a better luteal support in ... Objective:To determine whether a single dose of gonadotropin-releasing hormone(GnRH)agonist administered subcutaneously in addition to the regular progesterone supplementation could provide a better luteal support in antagonist protocol fresh embryo transfer cycles.Methods:This prospective,multicentric,cohort study included total 140 women,70 in each group.Controlled ovarian stimulation was carried out as per fixed GnRH antagonist protocol.The trigger was given with hCG.In vitro fertilization/intracytoplasmic sperm injection(IVF/ICSI)was performed and day-3 embryos were transferred.Patients were divided into groups 1 and 2 based on computer generated randomization sheet.Six days following oocyte retrieval,group 1 received 0.2 mg decapeptyl subcutaneously in addition to regular progesterone support while group 2 received progesterone only.Luteal support was given for 14 days to both groups;if pregnancy was confirmed luteal support was continued till 12 weeks of gestation.The clinical pregnancy rate was the primary outcome.The implantation rate,miscarriage rate,live birth delivery rate,and multiple pregnancy rates were the secondary outcomes.Results:A total of 140 patients were analysed,70 in each group.Clinical pregnancy rates(47.1%vs.35.7%;P=0.17),implantation rates(23.4%vs.18.1%,P=0.24),live birth delivery rates(41.4%vs.27.1%,P=0.08),and multiple pregnancy rates(21.2%vs.16.0%,P=0.74)were higher in group 1 than in group 2.Group 1 had a lower miscarriage rate than group 2(5.7%vs.8.6%;P=0.75).However,these differences were not statistically significant between the two groups.Conclusions:Administration of a single dose of GnRH agonist in addition to regular natural micronized vaginal progesterone as luteal support in GnRH antagonist protocol cycles marginally improves implantation rates,clinical pregnancy rates,and live birth delivery rates.However,more studies with higher sample sizes are needed before any conclusive statements about GnRH agonist as luteal phase support can be made. 展开更多
关键词 GnRH agonist TRIPTORELIN IVF Ovum pick up Luteal phase support Antagonist protocol Cleavage stage Fresh embryo transfer Live birth delivery rate
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Transforming Molecules into Medicines: Role of CDMOS in Phase-Appropriate Technology Transfers in Advancing Pharmaceutical Innovation
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作者 Kishore Kumar Hotha 《Advances in Chemical Engineering and Science》 2023年第3期203-223,共21页
CDMOs are emerging as critical drivers of innovation within the pharmaceutical and biotech industries. As the pharmaceutical industry continues to evolve, we can expect to see CDMOs play an increasingly important role... CDMOs are emerging as critical drivers of innovation within the pharmaceutical and biotech industries. As the pharmaceutical industry continues to evolve, we can expect to see CDMOs play an increasingly important role in drug development and manufacturing. Many companies within these sectors are now leveraging the expertise of CDMOs through technology transfers to foster innovation and enhance the development of new drug products. In the extensive field of drug development, technology transfer plays a crucial role at multiple stages, ranging from preclinical phases to commercialization. By working closely with drug developers, CDMOs can ensure that technologies are transferred seamlessly between phases of drug development, allowing for a more efficient and cost-effective development process. CDMOs also bring a wealth of experience in various areas of drug development, including process development, analytical testing, quality control, and manufacturing. This expertise, combined with a focus on innovation, can help drug developers to overcome technical challenges and optimize their drug development programs. CDMOs can provide drug developers with various manufacturing capabilities, from small-scale clinical trials to large-scale commercial production. This flexibility allows drug developers to focus on their core competencies while relying on CDMOs to provide the necessary infrastructure and support for drug manufacturing. The critical role of CDMOs in advancing pharmaceutical innovation in phase-appropriate technology transfer where there will be a lot of effort and patience with strong technical expertise is required. This article explores the various types of Technology transfer from preclinical to commercial stages and successful strategies to foster innovation. 展开更多
关键词 Technology transfer CDMO INNOVATION PRECLINICAL GMP phase Appropriate Method Development phase-1 Commercial Manufacturing Continuous Improvement Lifecycle Management
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Coherent optical frequency transfer via 972-km fiber link
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作者 邓雪 张翔 +8 位作者 臧琦 焦东东 王丹 刘杰 高静 许冠军 董瑞芳 刘涛 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期277-282,共6页
We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase lockin... We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase locking loop in the conventional active phase control scheme,the passive phase noise cancellation is realized by feeding double-trip beat-note frequency to the driver of the acoustic optical modulator at the local site.This passive scheme exhibits fine robustness and reliability,making it suitable for long-distance and noisy fiber links.An optical regeneration station is used in the link for signal amplification and cascaded transmission.The phase noise cancellation and transfer instability of the 972-km link is investigated,and transfer instability of 1.1×10^(-19)at 10^(4)s is achieved.This work provides a promising method for realizing optical frequency distribution over thousands of kilometers by using fiber links. 展开更多
关键词 optical frequency transfer fiber link phase noise cancellation
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Heat and Mass Transfers in a Two-Phase Stratified Turbulent Fluid Flow in a Geothermal Pipe with Chemical Reaction
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作者 Eric M. Nyariki Mathew N. Kinyanjui Jeconia O. Abonyo 《Journal of Applied Mathematics and Physics》 2023年第2期484-513,共30页
This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing... This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing the flow were solved using the Finite Difference Method. The effects of various physical parameters on the concentration, skin friction, heat, and mass transfers have been determined. Analysis of the results obtained indicated that the coefficient of skin friction decreased with an increase in Reynolds number and solutal Grasholf number, the rate of heat transfer increased with an increase in Eckert number, Prandtl number, and angle of inclination, and the rate of mass transfer increased with increase in Reynolds number, Chemical reaction parameter and angle of inclination. The findings would be useful to engineers in designing and maintaining geothermal pipelines more effectively. 展开更多
关键词 TWO-phase Turbulence Non-Newtonian INCLINATION Heat transfer Mass transfer STRATIFIED
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Paraffin–CaCl_(2)·6H_(2)O dosage effects on the strength and heat transfer characteristics of cemented tailings backfill
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作者 Hai Li Aibing Jin +2 位作者 Shuaijun Chen Yiqing Zhao You Ju 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期60-70,共11页
The challenge of high temperatures in deep mining remains harmful to the health of workers and their production efficiency The addition of phase change materials (PCMs) to filling slurry and the use of the cold storag... The challenge of high temperatures in deep mining remains harmful to the health of workers and their production efficiency The addition of phase change materials (PCMs) to filling slurry and the use of the cold storage function of these materials to reduce downhole temperatures is an effective approach to alleviate the aforementioned problem.Paraffin–CaCl_(2)·6H_(2)O composite PCM was prepared in the laboratory.The composition,phase change latent heat,thermal conductivity,and cemented tailing backfill (CTB) compressive strength of the new material were studied.The heat transfer characteristics and endothermic effect of the PCM were simulated using Fluent software.The results showed the following:(1) The new paraffin–CaCl_(2)·6H_(2)O composite PCM improved the thermal conductivity of native paraffin while avoiding the water solubility of CaCl_(2)·6H_(2)O.(2) The calculation formula of the thermal conductivity of CaCl_(2)·6H_(2)O combined with paraffin was deduced,and the reasons were explained in principle.(3) The“enthalpy–mass scale model”was applied to calculate the phase change latent heat of nonreactive composite PCMs.(4)The addition of the paraffin–CaCl_(2)·6H_(2)O composite PCM reduced the CTB strength but increased its heat absorption capacity.This research can give a theoretical foundation for the use of heat storage backfill in green mines. 展开更多
关键词 paraffin–CaCl_(2)·6H_(2)O heat transfer simulation heat calculation phase change material-based backfill latent heat of formula
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Clinical Effects of the Follicular Phase Long Regimen and Luteal Phase Long Regimen on Ovulation Induction in IVF-ET Treatment: A Meta-Analysis
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作者 Zhouxiang Chen Mingyu Ouyang 《Journal of Clinical and Nursing Research》 2024年第5期114-123,共10页
Objective:To systematically evaluate the clinical effects of the follicular phase long regimen and the luteal phase long regimen on ovulation induction in IVF-ET treatment.Methods:Databases including PubMed,Embase,Coc... Objective:To systematically evaluate the clinical effects of the follicular phase long regimen and the luteal phase long regimen on ovulation induction in IVF-ET treatment.Methods:Databases including PubMed,Embase,Cochrane Library,CNKI,Chinese Biomedical Literature(CBM),VIP,Wanfang,and others were searched up to January 2021.Clinical studies on ovulation induction using the follicular phase long regimen and luteal phase long regimen in IVF-ET treatment were identified.Literature screening,data extraction,and quality evaluation were conducted based on inclusion and exclusion criteria.Meta-analysis was performed using RevMan 5.3 software.Results:After screening,a total of 11 studies were included,comprising 21,544 patients:9,974 in the follicular phase long regimen group and 11,570 in the luteal phase long regimen group.The meta-analysis results were as follows:(1)The number of Gn days and the total amount of Gn in the follicular phase long regimen were higher than those in the luteal phase long regimen(P<0.05);(2)The number of eggs obtained in the follicular phase long regimen was higher than that in the luteal phase long regimen(P<0.05).There were no significant differences in the rate of embryo optimization and cycle cancellation between the two groups(P>0.05);(3)The embryo implantation rate and clinical pregnancy rate in the follicular phase long regimen were higher than those in the luteal phase long regimen(P<0.05),while the abortion rate in the follicular phase long regimen was lower than that in the luteal phase long regimen(P<0.05).Conclusion:Compared to the luteal phase long regimen,the follicular phase long regimen involves more Gn days and a higher total amount of Gn.The optimal embryo rate and cycle cancellation rate were similar between the regimens,but the follicular phase long regimen resulted in more eggs,significantly improved the implantation and clinical pregnancy rates,and reduced the abortion rate.However,these conclusions require further validation through more multicenter,large-sample RCT studies. 展开更多
关键词 In vitro fertilization and embryo transfer(IVF-ET) Follicular phrase long regimen Luteal phase long regimen META-ANALYSIS
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INFLUENCE OF PHASE RATIO ON PACKING EFFICIENCY IN COLUMNS FOR MASS TRANSFER PROCESSES 被引量:1
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作者 Reinhard Billet Michael Schultes 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1997年第2期25-34,共10页
The phase ratio has been found to affect the packing efficiency in packed columns.To ac-count for the effect,a model is set up to correlate the height of a mass transfer unit with the phaseratio with reasonable accura... The phase ratio has been found to affect the packing efficiency in packed columns.To ac-count for the effect,a model is set up to correlate the height of a mass transfer unit with the phaseratio with reasonable accuracy.Proposed also is a correlation that allows to predict the efficiency inquestion at any given liquid-gas ratio using the knowledge of other efficiency values at other liquid-gas ratios. 展开更多
关键词 phase RATIO HEIGHT of a transfer unit PACKINGS
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Microwave frequency transfer over a 112-km urban fiber link based on electronic phase compensation 被引量:4
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作者 薛文祥 赵文宇 +4 位作者 全洪雷 赵粹臣 邢燕 姜海峰 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期207-211,共5页
We demonstrate the transmission of a microwave frequency signal at 10 GHz over a 112-km urban fiber link based on a novel simple-architecture electronic phase compensation system.The key element of the system is the l... We demonstrate the transmission of a microwave frequency signal at 10 GHz over a 112-km urban fiber link based on a novel simple-architecture electronic phase compensation system.The key element of the system is the low noise frequency divider by 4 to differentiate the frequency of the forward signal from that of the backward one,thus suppressing the effect of Brillouin backscattering and parasitic reflection along the link.In terms of overlapping Allan deviation,the frequency transfer instability of 4.2×10-15 at 1-s integration time and 1.6×10-18 at one-day integration time was achieved.In addition,its sensitivity to the polarization mode dispersion in fiber is analyzed by comparing the results with and without laser polarization scrambling.Generally,with simplicity and robustness,the system can offer great potentials in constructing cascaded frequency transfer system and facilitate the building of fiber-based microwave transfer network. 展开更多
关键词 microwave frequency transfer phase compensation polarization mode dispersion
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Experimental study of the mass transfer behavior of carbon dioxide absorption into ternary phase change solution in a packed tower 被引量:2
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作者 Yihan Yin Aoqian Qiu +2 位作者 Hongxia Gao Yanqing Na Zhiwu Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第3期135-142,共8页
Phase change absorbents for CO_(2)are of great interest because they are expected to greatly reduce the heat energy consumption during the regeneration process.Compared with other phase change absorbents,monoethanolam... Phase change absorbents for CO_(2)are of great interest because they are expected to greatly reduce the heat energy consumption during the regeneration process.Compared with other phase change absorbents,monoethanolamine(MEA)-sulfolane-water is inexpensive and has a fast absorption rate.It is one of the most promising solvents for large-scale industrial applications.Therefore,this study investigates the mass transfer performance of this phase change system in the process of CO_(2)absorption in a packed tower.By comparing the phase change absorbent and the ordinary absorbent,it is concluded that the use of MEA/sulfolane phase change absorbent has significantly improved mass transfer efficiency compared to a single MEA absorbent at the same concentration.In the 4 mol·L^(-1)MEA/5 mol·L^(-1)sulfolane system,the CO_(2)loading of the upper liquid phase after phase separation is almost zero,while the volume of the lower liquid phase sent to the desorption operation is about half of the total volume of the absorbent,which greatly reduces the energy consumption.This study also investigates the influence of operating parameters such as lean CO_(2)loading,gas and liquid flow rates,CO_(2)partial pressure,and temperature on the volumetric mass transfer coefficient(K_(G)α_(V)).The research shows that K_(G)α_(V) increases with increasing liquid flow rate and decreases with the increase of lean CO_(2)loading and CO_(2)partial pressure,while the inert gas flow rate and temperature have little effect on K_(G)α_(V).In addition,based on the principle of phase change absorption,a predictive equation for the K_(G)α_(V) of MEA-sulfolane in the packed tower was established.The K_(G)α_(V) obtained from the experiment is consistent with the model prediction,and the absolute average deviation(AAD)is 7.8%. 展开更多
关键词 Monoethanolamine-sulfolane-water phase change solution Mass transfer Packed tower
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Synthesis of Hydroxypropyl Guar Gum by Phase Transfer Catalysis 被引量:1
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作者 RongChunXIONG MingZhuCHANC JianMingCHEN NanZHOU GangWEI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第4期545-546,共2页
HGG (Hydroxypropyl guar gum) was synthesized by phase transfer catalysis for the first time. The effects of alkalinity, phase transfer catalyst, etherification, pH value, temperature, reaction time and stirring spee... HGG (Hydroxypropyl guar gum) was synthesized by phase transfer catalysis for the first time. The effects of alkalinity, phase transfer catalyst, etherification, pH value, temperature, reaction time and stirring speed were investigated. An optimal synthetic reaction technology was established, namely, dose of guar gum is 100 g, propylene oxide 40-50 g, HTAC (hexadecyl trimethyl ammonium chloride ) 1.3-1.7 g, pH value 10-10.5, temperature 45-50℃, and reaction time 3-4 hours. The result shows that the improved HGG has high viscosity. Its dissolution speed, content of insoluble residue, colloid light transparency and stability are apparently superior to guar flour. 展开更多
关键词 Guar gum hydroxypropyl guar gum chemical modification phase transfer catalysis.
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One-pot Synthesis of 1-Aryloxyacety l-4-(4'-nitrophenyloxyacetyl)-thiosemicarbazides under Phase Transfer Catalysis and Microwave Irradiation 被引量:1
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作者 Zheng LI Xi Cun WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第8期717-720,共4页
The 1-aryloxyacetyl-4-(4-nitrophenyloxyacetyl)-thiosemicarbazides (3a-h) are synthe- sized via reaction of 4-nitrophenyloxyacetyl chloride with ammonium thiocyanate and aryloxyacetic hydrazides (2a-h) under phase tran... The 1-aryloxyacetyl-4-(4-nitrophenyloxyacetyl)-thiosemicarbazides (3a-h) are synthe- sized via reaction of 4-nitrophenyloxyacetyl chloride with ammonium thiocyanate and aryloxyacetic hydrazides (2a-h) under phase transfer catalysis and microwave irradiation in excellent yield. 展开更多
关键词 Diaryloxyacetyl thiosemicarbazide phase transfer catalysis microwave irradiation.
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New Phase Transfer Agent for Dye: Application for Hyperbranched Poly (ester-amine) 被引量:1
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作者 TengQIU LiMingTANG XinLinTUO DeShanLIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第8期931-934,共4页
Hydrophilic hyperbranched poly(ester-amine) (HPEA) synthesized from diethanolamine and methyl acrylate was used as phase transfer agent for the first time to transfer methyl orange (MO) from water into chloroform. Thi... Hydrophilic hyperbranched poly(ester-amine) (HPEA) synthesized from diethanolamine and methyl acrylate was used as phase transfer agent for the first time to transfer methyl orange (MO) from water into chloroform. This process was quantified by UV-Vis spectra. A possible mechanism was put forward based on the formation of amphiphilic aggregates. 展开更多
关键词 Hyperbranched poly(ester-amine) phase transfer agent dye.
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Heat Transfer Characteristics of Work Fluid Including Phase Change Material That Flow into Heating Surface from Narrow Path 被引量:1
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作者 Shin-Ichi Morita Yasutaka Hayamizu +4 位作者 Takanobu Yamada Akihiko Horibe Naoto Haruki Toshiaki Setoguchi Kazuma Adachi 《Open Journal of Fluid Dynamics》 2014年第5期454-462,共9页
Use of the low temperature (less than 100°C) energy contributes to effective use of heat resources. The cost recovery by power generation is difficult by using an existing system (the binary cycle or the thermoel... Use of the low temperature (less than 100°C) energy contributes to effective use of heat resources. The cost recovery by power generation is difficult by using an existing system (the binary cycle or the thermoelectric conversion element), because the initial investment is large. The final purpose of this research is development of the low temperature difference drive engine supposing use in a hot-springs resort as a power source for electric power generation. In order that a traveler may look at and delight a motion of an engine, it is made to drive at low-speed number of rotations. An engine cycle of this study is aimed at the development of Stirling cycle engine which can maintain high efficiency in small size. This kind of engine has simple structure;it brings low cost, and it is easy to perform maintenance. However, it is difficult to obtain enough output by this type of engine, because of its low temperature difference. This paper deals with the heat transfer characteristic that the working fluid including a phase change material flows into the heating surface from the narrow path. In order to increase the amount of the heat transmission, Diethylether is added to the working fluid. Diethylether is selected as a phase change material (PCM) that has the boiling point which exists between the heat source of high temperature and low temperature. The parameters of the experiment are additive amount of PCM, rotational speed of the displacer piston and temperature of heat transfer surface. It is shown that it is possible to make exchange of heat amount increase by adding phase change material. The result of this research shows the optimal condition of the difference in temperature in heat processing, number of revolutions, and addition concentration of PCM. 展开更多
关键词 phase CHANGE Material Heat transfer Low Temperature DIFFERENCE Working FLUID
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Numerical investigation of fluid phase momentum transfer in carbonate acidizing 被引量:1
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作者 Cun-Qi Jia Kamy Sepehrnoori +2 位作者 Hai-Yang Zhang Yong-Fei Yang Jun Yao 《Petroleum Science》 SCIE CAS CSCD 2022年第2期639-650,共12页
This work mainly studies the effect of fluid phase momentum transfer mechanisms on the acidizing results,including the retardation effect of the porous structure and the interaction between the fluid phase,such as vis... This work mainly studies the effect of fluid phase momentum transfer mechanisms on the acidizing results,including the retardation effect of the porous structure and the interaction between the fluid phase,such as viscous dissipation and inertial effect.The results show that the acid fluid momentum transfer is influenced by the complex porous structure and fluid viscous dissipation.Eventually,the Stokes-Darcy equation is recommended to be adopted to describe the fluid phase momentum transfer in the following numerical simulation studies of the carbonate acidizing process.Based on this model,a parametric research is carried out to investigate the impact of acid on rock physical characteristics in the stimulation process.Increasing the acid concentration appears to minimize the quantity of acid consumed for the breakthrough.The acid surface reaction rate has a considerable impact on the pore volume to breakthrough and the optimum acid injection rate.The influence of permeability on the acidizing results basically shows a negative correlation with the injection rate.The difference between the acidizing curves of different permeability gradually becomes insignificant with the decrease in injection rate.The existence of isolated fracture and vug significantly reduces acid consumption for the breakthrough. 展开更多
关键词 Fluid phase momentum transfer Carbonate acidizing Continuum model Reactive flow simulation
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Catalytic Oxidation of Cyclohexene to Adipic Acid with a Reaction-Controlled Phase-Transfer Catalyst 被引量:13
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作者 GUO Minglin (College of Materials and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300160, China) 《催化学报》 SCIE CAS CSCD 北大核心 2003年第7期483-484,共2页
关键词 催化氧化反应 环己烯 脂肪酸 反应控制 相转移催化剂 癸钨酸盐 十二钨磷酸盐 有机合成
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THE REACTION OF AROMATIC ALDEHYDES WITH p-NITROBENZYLLIBUTYLTELLURONIUM BROMIDE BY PHASE TRANSFER CATALYSIS 被引量:1
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作者 Qi ZHONG Jian Guo SHAO Chang Qing LIU Rong Jian LU Chemistry Department,Yangzhou Teachers College,Yangzhou,225002 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期275-276,共2页
Under the condition of solid-liquid phase transfer catalysis, olefins were obtained by the reaction of p-nitrobenzyldibutyltelluronium bromide with aromatic aldehyde.Under the condition of liquid-liquid phase transfer... Under the condition of solid-liquid phase transfer catalysis, olefins were obtained by the reaction of p-nitrobenzyldibutyltelluronium bromide with aromatic aldehyde.Under the condition of liquid-liquid phase transfer catalysis,however,different products were obtained due to the reactivity of different bases or aldehydes. 展开更多
关键词 CHC THE REACTION OF AROMATIC ALDEHYDES WITH p-NITROBENZYLLIBUTYLTELLURONIUM BROMIDE BY phase transfer CATALYSIS
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Selective oxidation of cyclopentene with H2O2 by using H3PW12O40 and TBAB as a phase transfer catalyst 被引量:3
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作者 Yaling Luo Changjun Liu +3 位作者 Hairong Yue Siyang Tang Yingming Zhu Bin Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1851-1856,共6页
The selective oxidation of cyclopentene by aqueous H2O2 using H3PW12O40 and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantl... The selective oxidation of cyclopentene by aqueous H2O2 using H3PW12O40 and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantly improved the oxidation selectivity of cyclopentene. The effects of the reaction conditions on the conversion of cyclopentene were investigated in detail. The optimal reaction conditions are as follows: the H3PW12O40 to TBAB molar ratio, 1:1–1:3;H3PW12O40 to cyclopentene molar ratio,0.54:100–0.64:100;and molar ratio of H2O2 to cyclopentene, 1.6:1. The conversion reached to 59.8% in 4h at 35.0 ℃, while the selectivity of glutaraldehyde was 38.0% and the selectivity of 1,2-cyclopentanediol was 55.6%. In addition, a route for oxidation of cyclopentene by aqueous H2O2 using a heteropoly acid and quaternary ammonium salt as a phase transfer catalyst was proposed. 展开更多
关键词 GLUTARALDEHYDE CYCLOPENTENE OXIDATION phase-transfer HETEROPOLY acid
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Phase Transfer Research for Heteropolyanions Containing Cr(Ⅲ),Mn(Ⅳ),Co(Ⅱ),Zn(Ⅱ) 被引量:1
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作者 ZHANG Shu-yun HUANG Ru-dan +1 位作者 YU Xin-wu LI Baitao and WANG En-bo(Departnient of Chemistry,Northeast Normal University,Changchun,130024) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1996年第4期397-400,共4页
PhaseTransferResearchforHeteropolyanionsContainingCr(Ⅲ),Mn(Ⅳ),Co(Ⅱ),Zn(Ⅱ)ZHANGShu-yun;HUANGRu-dan;YUXin-wu;L... PhaseTransferResearchforHeteropolyanionsContainingCr(Ⅲ),Mn(Ⅳ),Co(Ⅱ),Zn(Ⅱ)ZHANGShu-yun;HUANGRu-dan;YUXin-wu;LIBaitaoandWANGEn-... 展开更多
关键词 s:Heteropolyanions phase transfer Cr(Ⅲ) Mn(Ⅳ) Co(Ⅱ) Zn(Ⅱ)
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Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst 被引量:5
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作者 Zhi Huan Weng Jin Yan Wang Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期936-938,共3页
一系列 heteropolytungstates 被综合了并且作为催化剂利用了与水的过氧化氢催化本甲基酒精的氧化。结果显示三这些催化剂显示出控制反应的阶段转移催化作用的性质,并且他们有优秀催化能力到本甲基酒精的氧化。没有另外的副产品被气相... 一系列 heteropolytungstates 被综合了并且作为催化剂利用了与水的过氧化氢催化本甲基酒精的氧化。结果显示三这些催化剂显示出控制反应的阶段转移催化作用的性质,并且他们有优秀催化能力到本甲基酒精的氧化。没有另外的副产品被气相色谱检测。一旦过氧化氢完全被消费,催化剂从催化剂的溶剂,和结果猛抛再循环证明催化剂有高稳定性。 展开更多
关键词 异质多钨酸盐 苯甲醇 相转移催化剂 苯甲醛 过氧化氢
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