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ON A UNIVERSAL INEQUALITY FOR APPROXIMATE PHASE ISOMETRIES
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作者 戴端旭 阙海新 +1 位作者 孙龙发 郑本拓 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期823-838,共16页
Let X and Y be two normed spaces.Let U be a non-principal ultrafilter on N.Let g:X→Y be a standard ε-phase isometry for someε≥ 0,i.e.,g(0)=0,and for all u.v ∈ X,||‖g(u)+g(v)‖±‖g(u)-g(v)‖|-|‖u+v‖±... Let X and Y be two normed spaces.Let U be a non-principal ultrafilter on N.Let g:X→Y be a standard ε-phase isometry for someε≥ 0,i.e.,g(0)=0,and for all u.v ∈ X,||‖g(u)+g(v)‖±‖g(u)-g(v)‖|-|‖u+v‖±‖u-v‖| |≤ε.The mapping g is said to be a phase isometry provided that ε=0.In this paper,we show the following universal inequality of g:for each u^(*) ∈ w^(*)-exp ‖u^(*)‖B_(x^(*)),there exist a phase function σ_(u^(*)):X→{-1,1} and φ ∈ Y^(*) with ‖φ‖=‖u^(*)‖≡α satisfying that|(u^(*),u)-σ_(u^(*))(u)<φ,g(u)>)|≤5/2εα,for all u ∈ X.In particular,let X be a smooth Banach space.Then we show the following:(1) the universal inequality holds for all u^(*) ∈ X^(*);(2) the constant 5/2 can be reduced to 3/2 provided that Y~*is strictly convex;(3) the existence of such a g implies the existence of a phase isometryΘ:X→Y such that■ provided that Y^(**) has the w^(*)-Kadec-Klee property(for example,Y is both reflexive and locally uniformly convex). 展开更多
关键词 ε-phase isometry phase isometry Banach space
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The growth ofβphase in Mg-Gd-Y-Ni alloy by experimental and first-principles study
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作者 Yiqiang Hao Lei Zhou +2 位作者 Zhiqing Chen Zhixian Zhao Bin Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期506-515,共10页
The paper reports on the atomic investigation aboutβphase in Mg_(96)Gd_(2)Y_(1)Ni_(1) alloy by using the first-principles study and the high-angle annular dark-field scanning transmission electron microscope(HAADF-ST... The paper reports on the atomic investigation aboutβphase in Mg_(96)Gd_(2)Y_(1)Ni_(1) alloy by using the first-principles study and the high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM)corrected by atomic Cs.By using HAADF-STEM,the rectangularβphases were observed in the underage and peak aging stages in Mg_(96)Gd_(2)Y_(1)Ni_(1) alloy.Theβphase could be precipitated from the previously precipitatedβphase,and theβphase grew in steps when it was precipitated.A special transition structure of three atomic layer thicknesses was first observed at the edge of theβphase and the structure of this interface is probably as theβ/Mg_(1) interface for the analysis of thermodynamic characterization and electronic characterization.Theβ'phase and theβ_(H) structure were precipitated only at the edge of the length directions of theβphase.Theβ'phase continues to grow into aβphase directly without the formation ofβ_(1) phase,resulting in an increase in the length of theβphase,which is discovered for the first time. 展开更多
关键词 HAADF-STEM First-principles study Mg-Gd-Y-Ni alloy βphase GROWTH iNTERFACE
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Honeymoon phase in type 1 diabetes mellitus: A window of opportunity for diabetes reversal?
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作者 Madhukar Mittal Pradakshna Porchezhian Nitin Kapoor 《World Journal of Clinical Cases》 SCIE 2024年第1期9-14,共6页
The knowledge of the pathogenesis of type 1 diabetes mellitus(T1DM)continues to rapidly evolve.The natural course of the disease can be described in four clinical stages based on the autoimmune markers and glycemic st... The knowledge of the pathogenesis of type 1 diabetes mellitus(T1DM)continues to rapidly evolve.The natural course of the disease can be described in four clinical stages based on the autoimmune markers and glycemic status.Not all individuals of T1DM progress in that specific sequence.We hereby present a case of T1DM with a classical third phase(honeymoon phase)and discuss the intri-cacies of this interesting phase along with a possible future promise of“cure”with the use of immunotherapies.We now know that the course of T1DM may not be in only one direction towards further progression;rather the disease may have a waxing and waning course with even reversal of type 1 diabetes concept being discussed.The third phase popularly called the“honeymoon phase”,is of special interest as this phase is complex in its pathogenesis.The honeymoon phase of T1DM seems to provide the best window of opportunity for using targeted therapies using various immunomodulatory agents leading to the possibility of achieving the elusive“diabetes reversal”in T1DM.Identifying this phase is therefore the key,with a lot of varying criteria having been proposed. 展开更多
关键词 Diabetes reversal Diabetes remission Type 1 diabetes Honeymoon phase iMMUNOMODULATiON
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Deep learning assisted variational Hilbert quantitative phase imaging 被引量:2
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作者 Zhuoshi Li Jiasong Sun +7 位作者 Yao Fan Yanbo Jin Qian Shen Maciej Trusiak Maria Cywińska Peng Gao Qian Chen Chao Zuo 《Opto-Electronic Science》 2023年第4期1-11,共11页
We propose a high-accuracy artifacts-free single-frame digital holographic phase demodulation scheme for relatively lowcarrier frequency holograms-deep learning assisted variational Hilbert quantitative phase imaging(... We propose a high-accuracy artifacts-free single-frame digital holographic phase demodulation scheme for relatively lowcarrier frequency holograms-deep learning assisted variational Hilbert quantitative phase imaging(DL-VHQPI).The method,incorporating a conventional deep neural network into a complete physical model utilizing the idea of residual compensation,reliably and robustly recovers the quantitative phase information of the test objects.It can significantly alleviate spectrum-overlapping-caused phase artifacts under the slightly off-axis digital holographic system.Compared to the conventional end-to-end networks(without a physical model),the proposed method can reduce the dataset size dramatically while maintaining the imaging quality and model generalization.The DL-VHQPI is quantitatively studied by numerical simulation.The live-cell experiment is designed to demonstrate the method's practicality in biological research.The proposed idea of the deep learning-assisted physical model might be extended to diverse computational imaging techniques. 展开更多
关键词 quantitative phase imaging digital holography deep learning high-throughput imaging
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High-sensitivity phase imaging eddy current magneto-optical system for carbon fiber reinforced polymers detection
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作者 Jiang-Shan Ai Quan Zhou +5 位作者 Yi-Ping Liang Chun-Rui Feng Bing Long Li-Bing Bai Yong-Gang Wang Chao Ren 《Journal of Electronic Science and Technology》 EI CSCD 2023年第4期48-59,共12页
This paper proposed a high-sensitivity phase imaging eddy current magneto-optical (PI-ECMO) system for carbon fiber reinforced polymer (CFRP) defect detection. In contrast to other eddy current-based detection systems... This paper proposed a high-sensitivity phase imaging eddy current magneto-optical (PI-ECMO) system for carbon fiber reinforced polymer (CFRP) defect detection. In contrast to other eddy current-based detection systems, the proposed system employs a fixed position excitation coil while enabling the detection point to move within the detection region. This configuration effectively mitigates the interference caused by the lift-off effect, which is commonly observed in systems with moving excitation coils. Correspondingly, the relationship between the defect characteristics (orientation and position) and the surface vertical magnetic field distribution (amplitude and phase) is studied in detail by theoretical analysis and numerical simulations. Experiments conducted on woven CFRP plates demonstrate that the designed PI-ECMO system is capable of effectively detecting both surface and internal cracks, as well as impact defects. The excitation current is significantly reduced compared with traditional eddy current magneto-optical (ECMO) systems. 展开更多
关键词 Carbon fiber reinforced polymers Defect detection Eddy current magneto-optical Nondestructive testing phase imaging
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Improved Clamped Diode Based Z-Source Network for Three Phase Induction Motor
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作者 D.Bensiker Raja Singh R.Suja Mani Malar 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期683-702,共20页
The 3Φinduction motor is a broadly used electric machine in industrial applications,which plays a vital role in industries because of having plenty of beneficial impacts like low cost and easiness but the problems lik... The 3Φinduction motor is a broadly used electric machine in industrial applications,which plays a vital role in industries because of having plenty of beneficial impacts like low cost and easiness but the problems like decrease in motor speed due to load,high consumption of current and high ripple occurrence of ripples have reduced its preferences.The ultimate objective of this study is to control change in motor speed due to load variations.An improved Trans Z Source Inverter(ΓZSI)with a clamping diode is employed to maintain constant input voltage,reduce ripples and voltage overshoot.To operate induction motor at rated speed,different controllers are used.The conventional Proportional-Inte-gral(PI)controller suffers from high settling time and maximum peak overshoot.To overcome these limitations,Fractional Order Proportional Integral Derivative(FOPID)controller optimized by Gray Wolf Optimization(GWO)technique is employed to provide better performance by eliminating maximum peak overshoot pro-blems.The proposed speed controller provides good dynamic response and controls the induction motor more effectively.The complete setup is implemented in MATLAB Simulation to verify the simulation results.The proposed approach provides optimal performance with high torque and speed along with less steady state error. 展开更多
关键词 Three phase induction motor voltage source inverter improvedΓZSi with clamping diode Pi controller fractional order PiD controller gray wolf optimizer
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Chiral current regulation and detection of Berry phase in triangular triple quantum dots
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作者 齐月 刘一铭 +2 位作者 王援东 魏建华 朱振刚 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期91-97,共7页
Based on the hierarchical equations of motion(HEOM)calculation,we theoretically investigate the corresponding control of a triangular triple-quantum-dots(TTQD)ring which is connected to two reservoirs.We initially dem... Based on the hierarchical equations of motion(HEOM)calculation,we theoretically investigate the corresponding control of a triangular triple-quantum-dots(TTQD)ring which is connected to two reservoirs.We initially demonstrate by adding bias voltage and further adjusting the coupling strength between quantum dots,the chiral current induced by bias will go through a transformation of clockwise to counterclockwise direction and an unprecedented effective Hall angle will be triggered.The transformation is very rapid,with a corresponding characteristic time of 80-200 ps.In addition,by adding a magnetic flux to compensate for the chiral current in the original system,we elucidate the relationship between the applied magnetic flux and the Berry phase,which can realize direct measurement of the chiral current and reveal the magnetoelectric coupling relationship. 展开更多
关键词 chiral current Berry phase quantum dots quantum computation
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Progress of MJO Prediction at CMA from Phase I to Phase II of the Sub-Seasonal to Seasonal Prediction Project
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作者 Junchen YAO Xiangwen LIU +3 位作者 Tongwen WU Jinghui YAN Qiaoping LI Weihua JIE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第10期1799-1815,共17页
As one of the participants in the Subseasonal to Seasonal(S2S)Prediction Project,the China Meteorological Administration(CMA)has adopted several model versions to participate in the S2S Project.This study evaluates th... As one of the participants in the Subseasonal to Seasonal(S2S)Prediction Project,the China Meteorological Administration(CMA)has adopted several model versions to participate in the S2S Project.This study evaluates the models’capability to simulate and predict the Madden-Julian Oscillation(MJO).Three versions of the Beijing Climate Center Climate System Model(BCC-CSM)are used to conduct historical simulations and re-forecast experiments(referred to as EXP1,EXP1-M,and EXP2,respectively).In simulating MJO characteristics,the newly-developed high-resolution BCC-CSM outperforms its predecessors.In terms of MJO prediction,the useful prediction skill of the MJO index is enhanced from 15 days in EXP1 to 22 days in EXP1-M,and further to 24 days in EXP2.Within the first forecast week,the better initial condition in EXP2 largely contributes to the enhancement of MJO prediction skill.However,during forecast weeks 2–3,EXP2 shows little advantage compared with EXP1-M because the increased skill at MJO initial phases 6–7 is largely offset by the degraded skill at MJO initial phases 2–3.Particularly at initial phases 2–3,EXP1-M skillfully captures the wind field and Kelvin-wave response to MJO convection,leading to the highest prediction skill of the MJO.Our results reveal that,during the participation of the CMA models in the S2S Project,both the improved model initialization and updated model physics played positive roles in improving MJO prediction.Future efforts should focus on improving the model physics to better simulate MJO convection over the Maritime Continent and further improve MJO prediction at long lead times. 展开更多
关键词 Madden-Julian Oscillation(MJO) Subseasonal to Seasonal(S2S) prediction skill improvement initial phase
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New role of α phase in the fracture behavior and fracture toughness of a β-type bio-titanium alloy
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作者 Ran Wang Xiu Song +4 位作者 Lei Wang Yang Liu Mitsuo Niinomi Deliang Zhang Jun Cheng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第9期1756-1763,共8页
The role of α precipitates formed during aging in the fracture toughness and fracture behavior of β-type bio-titanium alloy Ti–29Nb–13Ta–4.6Zr(TNTZ) was studied. Results showed that the fracture toughness of the ... The role of α precipitates formed during aging in the fracture toughness and fracture behavior of β-type bio-titanium alloy Ti–29Nb–13Ta–4.6Zr(TNTZ) was studied. Results showed that the fracture toughness of the TNTZ alloy aged at 723 K decreases to the minimum of 72.07–73.19 kJ·m^(-2)when the aging time is extended to 4–8 h and then gradually increases and reaches 144.89 kJ·m^(-2)after 72 h. The decrease in fracture toughness within the aging time of 4–8 h is caused by the large stress concentration at the tip of acicular α precipitates with a high aspect ratio and the preferential crack propagation along the inhomogeneous acicular α precipitates distributed in “V-shape” and “nearly perpendicular shape”. When the aging time is extended to 8–72 h, the precrack tip is uniformly blunted, and the crack is effectively deflected by α precipitates with multi long axis directions, more high homogeneity, low aspect ratio, and large number density. Analysis of the effect of αprecipitates on the fracture behavior suggested that the number of long axis directions of α precipitates is the key controlling factor for the fracture behavior and fracture toughness of the TNTZ alloy aged for different times. 展开更多
关键词 fracture toughness Ti-29Nb-13Ta-4.6Zr alloy agedαphase crack tip blunting
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Nonadiabatic geometric phase in a doubly driven two-level system
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作者 刘伟新 汪涛 李卫东 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期314-320,共7页
We study theoretically the nonadiabatic geometric phase of a doubly driven two-level system with an additional relative phase between the two driving modes introduced in. It is shown that the time evolution of the sys... We study theoretically the nonadiabatic geometric phase of a doubly driven two-level system with an additional relative phase between the two driving modes introduced in. It is shown that the time evolution of the system strongly depends on this relative phase. The condition for the system returning to its initial state after a single period is given by the means of the Landau–Zener–Stückelberg–Majorana destructive interference. The nonadiabatic geometric phase accompanying a cyclic evolution is shown to be related to the Stokes phase as well as this relative phase. By controlling the relative phase, the geometric phase can characterize two distinct phases in the adiabatic limit. 展开更多
关键词 two-level system geometric phase Landau–Zener–Stückelberg–Majorana interference
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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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PROGRESS IN PHASE INVERSION EMULSIFICATION FOR EPOXY RESIN WATERBORNE DISPERSIONS 被引量:16
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作者 Zhen-zhong Yang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第2期137-143,共7页
In this review, our recent work in phase inversion emulsification (PIE) for polymer (especially epoxy resin) waterborne dispersions is summarized. Based on experimental results about PIE process, the physical mode... In this review, our recent work in phase inversion emulsification (PIE) for polymer (especially epoxy resin) waterborne dispersions is summarized. Based on experimental results about PIE process, the physical model is proposed which can guide the synthesis of the waterborne dispersions such as polymer/nanoparticle composite dispersion. In the presence of a latent curing catalyst, PIE can give a crosslinkable epoxy resin waterborne dispersion. The dispersions can form cured transparent coatings with some unique properties such as UV shielding. They are promising in functional coatings, waterborne resin matrices for composites, and sizing for high performance fibers. 展开更多
关键词 phase inversion emulsification Epoxy resin Waterborne dispersions.
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Phase I study of chimeric anti-CD20 monoclonal antibody in Chinese patients with CD20-positive non-Hodgkin's lymphoma 被引量:5
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作者 Lin Gui Xiaohong Han +10 位作者 Xiaohui He Yuanyuan Song Jiarui Yao Jianliang Yang Peng Liu Yan Qin Shuxiang Zhang Weijing Zhang Wenlin Gai Liangzhi Xie Yuankai Shi 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第2期197-208,共12页
Objective: This study was designed to determine the safety, pharmacokinetics and biologic effects of a humanmouse chimeric anti-CD20 monoclonal antibody (SCT400) in Chinese padents with CD20-positive B-cell non- Ho... Objective: This study was designed to determine the safety, pharmacokinetics and biologic effects of a humanmouse chimeric anti-CD20 monoclonal antibody (SCT400) in Chinese padents with CD20-positive B-cell non- Hodgkin's lymphoma (CD20 B-cell NHL). SCT400 has an identical amino acid sequence as rituximab, with the exception of one amino acid in the CH1 domain of the heavy chain, which is common in Asians. Methods: Fifteen patients with CD20+ B-cell NHL received dose-escalating SCT400 infusions (250 mg/m2: n=3; 375 mg/m2: n=9; 500 mg/m2: n=3) once weekly for 4 consecutive weeks with a 24-week follow-up period. The data of all patients were collected for pharmacoklnetics and pharmacodynamics analyses. Results: No dose-limiting toxicities were observed. Most drug-related adverse events were grade 1 or 2. Two patients had grade 3 or 4 ncutropenia. Under premedication, the drug-related infusion reaction was mild. A rapid, profound and durable depletion of circulating B cells was observed in all dose groups without significant effects on T cell count, natural killer (NK) cell count or immunoglobulin levels. No patient developed anti- SCT400 antibodies during the course of the study. SCT400 serum half-life (Tin), maximum concentration (Cmax and area under the curve (AUC) generally increased between the first and fourth infusions (P〈0.05). At the 375 mg/m2 dose, the T1/2 was 122.5±46.7 h vs. 197.0,75.0 11, respectively, and the Cmax was 200.6±20.2 pg/mL vs. 339.1±71.0 ng/mL, respectively. From 250 mg/m2 to 500 mg/m2, the Cmax and AUC increased significantly in a dose-dependent manner (P〈0.05). Patients with a high tumor burden had markedly lower serum SCT400 concenmations compared with those without or with a low tumor burden. Of the 9 assessable patients, 1 achieved complete response and 2 achieved partial responses. Conclusions; SCT400 is well-tolerated and has encouraging preliminary efficacy in Chinese patients with CD20+ B-cell NHL. 展开更多
关键词 Chimeric anti-CD20 monodonal antibody non-Hodgldn's lymphoma phase i study
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Precipitation of α_2 Phase in α+β Solution-Treated and Air-cooled Ti-Al-Sn-Zr-Mo-Si-Nd Alloys 被引量:4
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作者 Jun ZHANG and Dong LI Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China resent address: Shenyang University, Shenyang 110044, China E-mail: zhjun14@mailcity.com 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第3期315-317,共3页
A series of Ti-Al-Sn-Zr-Mo-Si-Nd alloys with various content of Al were solution treated in α+β phase field and air-cooled. The precipitation of a2 phase in cooling was investigated by transmission electron microsco... A series of Ti-Al-Sn-Zr-Mo-Si-Nd alloys with various content of Al were solution treated in α+β phase field and air-cooled. The precipitation of a2 phase in cooling was investigated by transmission electron microscopic analysis The precipitation characteristic of α2 phase was discussed. The precipitation of α2 phase would proceed by the nucleation and growth of α2 phase dependent on the diffusion of Al atoms. And a comparison on the difference of precipitation of α2 phase was carried out under the conditions of air-cooling and quenching in water. The investigation showed that the air-cooling and even quenching could supply enough time for the precipitation and growth of α2 phase when Al content reached a certain value even though far away from the stoichiometric composition of Ti3Al. 展开更多
关键词 Al Precipitation of phase in Solution-Treated and Air-cooled Ti-Al-Sn-Zr-Mo-Si-Nd Alloys Ti Mo Sn ZR ND Si
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Quasicrystalline Phase in As-cast Mg-Zn-Y-Zr Alloy 被引量:4
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作者 Yali TANG Ningfu SHEN and Xin YUAN (Research Center for Materials, Zhengzhou Institute of Technology, Zhengzhou, 450002, China)Zhiping LUO and Shaoqing ZHANG (Institute of Aeronautical Materials, Beijing,100095, China)(To whom correspondence should be ad 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第4期304-306,共3页
An icosahedral phase in as-cast Mg 5. 78Zn-0.89Y-0.48Zr (wt-%) alloy has been identified with transmission electron microscope (TPM) The selected area diffraction patterns (SADP) from the phase show a five-fold symme... An icosahedral phase in as-cast Mg 5. 78Zn-0.89Y-0.48Zr (wt-%) alloy has been identified with transmission electron microscope (TPM) The selected area diffraction patterns (SADP) from the phase show a five-fold symmetry of a quasicrystalline structure. The energy dispersive X-ray spectra (EDXS) indicate that the quaternary phase has a chemical composition of 67.6Zn-1 9.4Mg-8,1 Y-4 9Zr in at -% 展开更多
关键词 ZN ZR Quasicrystalline phase in As-cast Mg-Zn-Y-Zr Alloy AS
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β→α Transformation of γ-Phase in Sintered WC-Co Cemented Carbides 被引量:4
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作者 Shourong LIU (Tianjin Institute of Hard Alloy Tianjin 300222, China)Yi LIU (Shandong University Jinan 250100, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第5期398-400,共3页
Varying the morphology and the structure of γ-phase (Co-base Co-W-C solid solution) by means of altering the cooling rate and the preparing method of liquid sintered WC-Co cemented carbides samples, the mechanism of ... Varying the morphology and the structure of γ-phase (Co-base Co-W-C solid solution) by means of altering the cooling rate and the preparing method of liquid sintered WC-Co cemented carbides samples, the mechanism of fcc→hcp transformation of γ-phase in WC-Co alloy has been explored. The results show that, the cooling rate is an important affecting factor on fcc→hcp transformation of γ-phase and the fcc→hcp transformation is mainly a diffusive type when cooling WC-Co samples above room temperature 展开更多
关键词 WC CO phase in Sintered WC-Co Cemented Carbides Transformation of
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PREPARATION OF WATERBORNE ULTRAFINE PARTICLES OF EPOXY RESIN BY PHASE INVERSION TECHNIQUE 被引量:6
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作者 杨振忠 许元泽:王胜杰 +1 位作者 俞浩 蔡维真 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第1期92-96,共5页
Waterborne ultrafine particles of epoxy resin were prepared by phase inversion technique. The results of SEM revealed that the particles diameter was in the range of 50 to 100 nm and the effects on amount of water req... Waterborne ultrafine particles of epoxy resin were prepared by phase inversion technique. The results of SEM revealed that the particles diameter was in the range of 50 to 100 nm and the effects on amount of water required at phase inversion point were also discussed. 展开更多
关键词 waterborne ultrafine particles bisphenol A epoxy resin phase inversion technique
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HYDRODYNAMIC AND THERMODYNAMIC EFFECTS IN PHASE INVERSION EMULSIFICATION PROCESS OF EPOXY RESIN IN WATER 被引量:1
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作者 许元泽 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第2期155-161,共7页
The mechanism of phase inversion emulsification process (PIE) was studied for waterborne dispersion of highly viscous epoxy resin using non-ionic polymeric surfactants. Drop deformation and breakup, rheological prop... The mechanism of phase inversion emulsification process (PIE) was studied for waterborne dispersion of highly viscous epoxy resin using non-ionic polymeric surfactants. Drop deformation and breakup, rheological properties, conductivity, and particle size measurements reveal the micro-structural transition amid emulsification. It is revealed that strong flow causes water drop to burst with the formation of droplets and huge interface. Phase inversion corresponds to an abrupt rheological transition from a type of viscous melt with weak elasticity to a highly elastic type of aqueous gel. This implies that the phase inversion equivalent to a curvature inversion. Based on this, a geometric model is postulated to correlate process variables to the particle size. The coverage and conformation of the surfactant plays key role for the particle size of the final emulsion. The interactions of thermodynamic and hydrodynamic effects are also discussed. It is concluded that the thermodynamics control the PIE while the hydrodynamics drives the creation of interface and involves every step of PIE. 展开更多
关键词 phase inversion EMULSiFiCATiON RHEOLOGY WATERBORNE Epoxy resin
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Quality Management Model for Phase I Clinical Drug Trials:A Structural Equation Model 被引量:1
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作者 Yang ZHAO Qiu-xia YANG +1 位作者 Dan WANG Xin-ping ZHANG 《Current Medical Science》 SCIE CAS 2020年第3期586-593,共8页
This study aimed to construct a quality management model for phase I clinical drug trials.A cross-sectional survey was conducted and data were collected from 604 respondents at 69 institutions in China engaged in phas... This study aimed to construct a quality management model for phase I clinical drug trials.A cross-sectional survey was conducted and data were collected from 604 respondents at 69 institutions in China engaged in phase I clinical drug trials.Exploratory and confirmatory factor analyses were used to develop the survey tool.Structural equation modeling was used to construct a quality management model for phase I clinical drug trials.The results showed that the final survey tool had good reliability and validity(Cronbach’sα=0.938,root mean square error of approximation=0.074,comparative fit index=0.962,and Tucker—Lewis index=0.955).The model included five dimensions:government regulation,industry management,medical institution management,research team management,and contract research organization(CRO)management.In total,22 measurement items were obtained.The structural equation model indicated government regulation,industry management,medical institution management,and CRO management significantly affected the quality of phase I clinical drug trials(β=0.195,β=0.331,β=0.279,andβ=−0.267,respectively;P<0.05).Research team management had no effect on the quality of trials(β=0.041,P=0.610).In conclusion,the model is valuable for identifying factors influencing phase I clinical drug trials and guiding quality management practices. 展开更多
关键词 phase i clinical drug trials QUALiTY MANAGEMENT influence factor structural equation model
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PREPARATION OF BISPHENOL A EPOXY RESIN WATERBORNE DISPERSIONS BY THE PHASE INVERSION EMULSIFICATION TECHNIQUE 被引量:1
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作者 Zhen-zhong Yang De-lu Zhao Polymer Physics Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第1期33-38,共6页
The phase inversion emulsification technique (PIET) is an effective physical method for preparing waterborne dispersions of polymer resins. Some results concerning the preparation of bisphenol A epoxy resin waterborne... The phase inversion emulsification technique (PIET) is an effective physical method for preparing waterborne dispersions of polymer resins. Some results concerning the preparation of bisphenol A epoxy resin waterborne dispersions by PIET in our laboratory were summarized. Electrical properties, rheological behavior and morphological evolution during phase inversion progress were systematically characterized. The effects of the emulsifier concentration and emulsification temperature on phase inversion progress and the structural features of the waterborne particles were studied as well. The deformation and break up of water drops in a shear field were analyzed in terms of micro-theology, while the interaction and coalescence dynamics of water drops were discussed in terms of DLVO theory and Smoluchowski effective collision theory, respectively. Based on the experimental results and theoretical analysis, a physical model of phase inversion progress was suggested, by which the effects of the parameters on phase inversion progress and the structural features of the waterborne particles were interpreted and predicted. 展开更多
关键词 phase inversion EMULSiFiCATiON waterborne dispersions epoxy resin mechanism physical model
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