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Theoretical studies on the mechanism of α-hydroxy-acid gas-phase elimination process and its substituent effect

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Chinese Journal of Chemistry 1997年第4期15卷 313-317页

作者： SONG,wei-ping he,Shao-Ren FU,Xiao-YuanDepartment of Chemistry,Beijing Normal University,Beijing 100875,China Department of Chemistry Beijing Normal University Beijing 100875 China

The α-hydroxy-acid gas-phase elimination process has been studied theoretically by HF/*** calculated results can be summed up as follows:(1) The elimination process is a stepwise *** the first step,a 3-membered ring intermediate is formed via a 5-membered ring transition state;while the product is formed in the second step via a 3-membered ring transition state.(2) The obtained results of the substituent effect show that the increase of electronic donation of the alkyl groups is favorable for the *** substituents which show the electron-withdrawing inductive effect (e.g.-Cl,-CN,-CF3) are unfavorable for this process.

关键词： α-Hydroxy-acid gas-phase elimination mechanism

The effects of stereotactic body radiotherapy on peripheral natural killer and CD3~+CD56~+ NKT-like cells in patients with hepatocellular carcinoma

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hepatobiliary & Pancreatic Diseases International 2021年第3期20卷 240-250页

作者： Tian-Tian Li Jing Sun Quan Wang Wen-Gang Li wei-ping he Rui-Chuang Yang Xue-Zhang Duan Peking University 302 Clinical Medical School Beijing 100191China Radiation Oncology Department the Fifth Medical Center of Chinese PLA General HospitalXi Si Huan Middle RoadFengtai DistrictBeijing 100039China Research Center for Clinical&Translational Medicine the Fifth Medical Center of Chinese PLA General HospitalBeijing 100039China

Background: Both natural killer(NK) and CD3+CD56+ natural killer T(NKT)-like cells play critical roles in the antitumor response. This study aimed to explore the effects of stereotactic body radiotherapy(SBRT) on peripheral NK and NKT-like cells in patients with hepatocellular carcinoma(HCC), and to identify possible surface markers on these cells that correlate with the prognosis. Methods: Twenty-five HCC patients were prospectively enrolled in our study, and 10 healthy individuals were served as healthy controls. Flow cytometry was used to determine the counts and the percentages of peripheral NK and NKT-like cells, cells with certain receptors, and cells with intracellular interferon-γand TNF-α secretion at different time points, including time points of prior to SBRT, at post-SBRT, and 3-month and 6-month after treatment. The Kaplan-Meier method with the log-rank test was applied for survival analysis. Results: The peripheral NKT-like cells was increased at post-SBRT. Meanwhile, elevated levels of inhibitory receptors and reduced levels of activating receptors of NK cells were also observed in NK cells at post-SBRT, but the levels was not significantly different at 3-month and 6-month as compared with the baseline levels. Lower percentage of NKp30+ NK cells before SBRT and higher percentage of CD158b + NK cells after SBRT were associated with poor progression-free survival. In addition, higher percentage of CD3+CD56+ NKT-like cells was associated with a higher overall survival rate in HCC patients. Conclusions: SBRT has an apparent effect on both peripheral NK and CD3+ CD56+ NKT-like cells. Lower percentage of NKp30 + NK cells before SBRT and higher percentage of CD158b + NK cells after SBRT are correlated with poor patients' PFS. Higher percentage of CD3+ CD56+ NKT-like cells is associated with higher OS in HCC patients.

关键词： Nature killer cells hepatocellular carcinoma Nature killer T-like cells Stereotactic body radiotherapy

Research on thermal insulation materials properties under HTHP conditions for deep oil and gas reservoir rock ITP-Coring

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Petroleum Science 2024年第4期21卷 2625-2637页

作者： Zhi-Qiang he he-ping Xie Ling Chen Jian-ping Yang Bo Yu Zi-Jie wei Ming-Zhong Gao State Key Laboratory of Intelligent Construction and healthy Operation and Maintenance of Deep Underground Engineering College of Water Resource and Hydropower Sichuan University Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green Energy College of Civil and Transportation Engineering Shenzhen University School of Mechanical Engineering Sichuan University College of Polymer Science and Engineering Sichuan University

Deep oil and gas reservoirs are under high-temperature conditions, but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability, resulting in distorted resource assessments. The development of in situ temperaturepreserved coring(ITP-Coring) technology for deep reservoir rock is urgent, and thermal insulation materials are key. Therefore, hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials) were proposed as thermal insulation materials. The materials properties under coupled hightemperature and high-pressure(HTHP) conditions were tested. The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased; additionally,increasing temperature accelerated the process. High temperatures directly caused the thermal conductivity of the materials to increase; additionally, the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity. High temperatures weakened the matrix, and high pressures destroyed the HGM, which resulted in a decrease in the tensile mechanical properties of the materials. The materials entered the high elastic state at 150.C, and the mechanical properties were weakened more obviously, while the pressure led to a significant effect when the water absorption was above 10%. Meanwhile, the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86% at 100.C and 100 MPa, respectively, which meet the application requirements of the self-designed coring device. Finally, K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100.C and 100 MPa. To further improve the materials properties, the interface layer and EP matrix should be optimized. The results can provide references for the optimization and engineering application of materials and thus technical su

关键词： Deep oil and gas reservoir rock In situ temperature-preserved coring (ITP-Coring) Hollow glass microsphere/epoxy resin thermal insulation materials (HGM/EP materials) High-temperature and high-pressure (HTHP) Physical and mechanical properties

An adaptive finite-difference method for seismic traveltime modeling based on 3D eikonal equation

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Petroleum Science 2024年第1期21卷 195-205页

作者： Bao-ping Qiao Qing-Qing Li wei-Guang he Dan Zhao Qu-Bo Wu CNNC Beijing Research Institute of Uranium Geology Beijing 100029China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShangdongChina SINOPEC Geophysical Research Institute Nanjing211103JiangsuChina

3D eikonal equation is a partial differential equation for the calculation of first-arrival traveltimes and has been widely applied in many scopes such as ray tracing,source localization,reflection migration,seismic monitoring and tomographic *** recent years,many advanced methods have been developed to solve the 3D eikonal equation in heterogeneous ***,there are still challenges for the stable and accurate calculation of first-arrival traveltimes in 3D strongly inhomogeneous *** this paper,we propose an adaptive finite-difference(AFD)method to numerically solve the 3D eikonal *** novel method makes full use of the advantages of different local operators characterizing different seismic wave types to calculate factors and traveltimes,and then the most accurate factor and traveltime are adaptively selected for the convergent updating based on the Fermat *** with global fast sweeping describing seismic waves propagating along eight directions in 3D media,our novel method can achieve the robust calculation of first-arrival traveltimes with high precision at grid points either near source point or far away from source point even in a velocity model with large and sharp *** numerical examples show the good performance of the AFD method,which will be beneficial to many scientific applications.

关键词： 3D eikonal equation Accurate traveltimes Global fast sweeping 3D inhomogeneous media Adaptive finite-difference method

Manipulating the Phase Transition Behavior of Dual Temperature-Responsive Block Copolymers by Adjusting Composition and Sequence

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Chinese Journal of Polymer Science 2024年第2期42卷 176-187,I0006页

作者： Zhi Zou Xiang Xu Hai-Tao Zhao Jian-Nan Cheng wei-wei he Li-Fen Zhang Zhen-ping Cheng Suzhou key Laboratory of Macromolecular Design and Precision Synthesis Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationState and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of JiangsuSoochow UniversitySuzhou215123China

Temperature-responsive polymers have garnered significant attention due to their ability to respond to external *** this work,dual temperature-responsive block copolymers are synthesized via reversible addition-fragmentation chain transfer polymerization(RAFT)polymerization utilizing zwitterionic monomer methacryloyl ethyl sulfobetaine(SBMA) and N-isopropyl acrylamide(NIPAAm) as *** thermal responsive behaviors can be easily modulated by incorporating additional hydrophobic monomer benzyl acrylate(BN) or hydrophilic monomer acrylic acid(AA),adjusting concentration or pH,or varying the degree of polymerization of the block chain *** cloud points of the copolymers are determined by UV-Vis spectrophotometry,and these copolymers exhibit both controlled upper and lower critical solu bility temperatures(LCST and UCST) in aqueous *** study analyzes and summarizes the influencing factors of dual temperature responsive block copolymers by exploring the effects of various conditions on the phase transition temperature of temperature-sensitive polymers to explore the relationship between their properties and environment and structure to make them more selective in terms of temperature application range and regulation *** is very interesting that the introduction of poly-acrylic acid(PAA) segments in the middle of di-block copolymer PSBMA_(55)-b-PNIPAAm_(80) to form PSBMA_(55)-b-PAA_(x)-b-PNIPAAm_(80) results in a reversal of temperature-responsive behaviors from 'U'(LCST UCST) type,while the copolymer PSBMA_(55)-b-P(NIPAAm_(80)-co-AA_(x)) *** work provides a clue for tuning the phase transition behavior of polymers for manufacture of extreme smart materials.

关键词： Temperature responsive polymers High critical solubility temperature(UCST) Low critical solubility temperature(LCST) Block copolymers

Ultrathin and flexible MXene-contained electromagnetic interference shielding composite paper designed with a protective hydrogel film

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Journal of Materials Science & Technology 2024年第2期169卷 199-208页

作者： Jiasheng wei Lei Dai ping he Meng Zhu Feng Jiang Zhaoxiang Zhou Guiqiang Fei Tingzhou Lei College of Bioresources Chemical and Materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China Key Laboratory of Eco-Textiles Ministry of EducationJiangnan UniversityWuxi 214122China Zhejiang Shunpu New Material Technology Co. LtdLongyou 324404China College of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXi’an 710021China National-Local Joint Engineering Research Center of Biomass Refining and High-Quality Utilization Institute of Urban and Rural MiningChangzhou UniversityChangzhou 213164China

MXene-contained paper is a good choice to design ultrathin and flexible electromagnetic interference(EMI)shielding ***,the deficiencies in strength and stability of MXene-contained paper impede its practical ***,a composite paper was proposed to address the problems,in which a filter paper was modified with a three-layer structured surface via a facile layer-by-layer coating ***,the TEMPO-oxidized cellulose nanofibers(TOCN)/cationic starch(CS)/MXene gel layer and TOCN/MXene nacre structure layer ensured the good EMI shielding and mechanical performances of the composite paper,while the uppermost TOCN/CS hydrogel film layer mainly protected *** composite paper achieved an EMI SE of 40.3 dB at a thickness of merely 0.1894 mm(SE/t value of ca.212.8 dB mm^(−1),SSE/t values of ca.13216 dB cm 2 g^(−1))and the total MXene dosage was 20 g m^(−2).Its tensile strength could be up to 11.7 MPa while the original filter paper was 6.4 *** pieces of this composite papers could be easily packed together to attain an EMI SE of nearly 70 ***,the hydrogel film layer efficiently protected the MXene and maintained the EMI shielding performance of the composite paper when immersed in different liquids including water,HCl(1 M)and ethanol,due to the dense and compact structure of hydrogel film *** work provides a practical way to develop ultrathin,flexible and durable EMI shielding materials.

关键词： MXene Electromagnetic interference shielding Nanocellulose Hydrogel

Survival and prognostic factors in hepatitis B virus-related acute-on-chronic liver failure

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World Journal of Gastroenterology 2011年第29期17卷 3448-3452页

作者： Kun Huang Jin-Hua Hu Hui-Fen Wang wei-ping he Jing Chen XueZhang Duan Ai-Min Zhang Xiao-Yan Liu Liver Failure Treatment and Research Center 302 Military HospitalPeking University Health Science CenterBeijing 100191China Liver Failure Treatment and Research Center 302 Military HospitalBeijing 100039China

AIM:To investigate the survival rates and prognostic factors in patients with hepatitis B virus-related acuteon-chronic liver failure(HBV-ACLF).METHODS:Clinical data in hospitalized patients with HBV-ACLF admitted from 2006 to 2009 were retrospectively *** general conditions and survival were analyzed by survival analysis and Cox regression ***:A total of 190 patients were included in this *** overall 1-year survival rate was 57.6%.Patients not treated with antiviral drugs had a significantly higher mortality[relative risk(RR)=0.609,P=0.014].The highest risk of death in patients with ACLF was associated with hepatorenal syndrome(HRS)(RR=2.084,P=0.026),while other significant factors were electrolyte disturbances(RR=2.062,P=0.010),and hepatic encephalopathy(he)(RR=1.879,Pherapy has a strong effect on the prognosis of the patients with HBV-ACLF by improving their 1-year survival ***,electrolyte disturbances,and he also affect patient survival.

关键词： hepatitis B virus Acute-on-chronic liver failure Antiviral therapy Nucleosides Survival analysis

Privacy-Preserving Consensus-Based Distributed Economic Dispatch of Smart Grids via State Decomposition

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1250-1261页

作者： wei Chen Guo-ping Liu The authors are with the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

This paper studies the privacy-preserving distributed economic dispatch(DED)problem of smart *** autonomous consensus-based algorithm is developed via local data exchange with neighboring nodes,which covers both the islanded mode and the grid-connected mode of smart *** prevent power-sensitive information from being disclosed,a privacy-preserving mechanism is integrated into the proposed DED algorithm by randomly decomposing the state into two parts,where only partial data is *** objective is to develop a privacy-preserving DED algorithm to achieve optimal power dispatch with the lowest generation cost under physical constraints while preventing sensitive information from being *** this end,a comprehensive analysis framework is established to ensure that the proposed algorithm can converge to the optimal solution of the concerned optimization problem by means of the consensus theory and the eigenvalue perturbation *** particular,the proposed autonomous algorithm can achieve a smooth transition between the islanded mode and the grid-connected ***,rigorous analysis is given to show privacy-preserving performance against internal and external ***,case studies illustrate the feasibility and validity of the developed algorithm.

关键词： preserving autonomous mode

Attribution analysis of groundwater level fluctuation in the Xinxiang section of the Lower Yellow River's suspended river after the construction of the Xiaolangdi Reservoir

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Journal of Geographical Sciences 2024年第7期34卷 1348-1370页

作者： LI he ping Jianhua LENG wei MEI Xuemei ZHANG Min LIU Jiaqi School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou450001China College of Ecology and Environment Zhengzhou UniversityZhengzhou450001China Geothermal and Ecological Geology Research Center Zhengzhou UniversityZhengzhou450001China Institute of Geology and Geophysics CASBeijing100101China

The clear identification and quantification of the factors affecting groundwater systems is crucial for protecting groundwater resources and ensuring safety in agricultural *** Lower Yellow River(LYR)is a suspended river that replenishes groundwater continuously due to clear differences in the water head,especially in the Xinxiang *** its construction,the Xiaolangdi Reservoir has reversed the LYR’s *** accurately determine the factors influencing the groundwater level(GWL),the study area was divided into five subzones based on hydrogeology.A dynamic factor model(DFM),variational mode decomposition(VMD),and a multiple linear regression model were used to identify and quantify the factors influencing the *** impact of the suspended river on the groundwater before and after the construction of the Xiaolangdi Reservoir was *** results show that:(1)The rate of decrease in the GWL was 8.53×10^(–4)m/month,and the rate of decrease in the Yellow River water level(RWL)was 4.63×10^(–4)m/month.(2)Mountain front recharge(MFR)(scale=3 months)and precipitation(scale=9 months)were the dominant factors in subzones I and II,accounting for more than 40%of the fluctuation in the *** III was dominated by exploitation(scale=7 months)and precipitation(scale=12months),accounting for 28.43%,and 23.44%of changes in the GWL,*** subzone IV,agricultural irrigation(scale=12 months)was the major factor,accounting for32.47%of GWL changes,while in subzone V,the RWL(scale=12 months)accounted for52.52%of these changes.(3)The Xiaolangdi Reservoir has increased the lateral seepage of the suspended river and altered the inter-annual *** results of this study can provide a valuable reference for controlling groundwater overexploitation and ensuring water supply security.

关键词： groundwater level influencing factor dynamic factor analysis Xiaolangdi Reservoir Lower Yellow River lateral seepage of the Yellow River