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Synthesis of dimethyl ether from methane mediated by HBr

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Journal of Natural Gas Chemistry 2009年第3期18卷 306-311页

作者： qin you Zhen Liu Wensheng Li Xiaoping Zhou Department of Chemical Engineering Hunan University Changsha 410082 Hunan China College of Life Science and Pharmaceutical Engineering Nanjing University of Technology Nanjing 210009 Jiangsu China

Dimethyl ether （DME） was synthesized from methane through a two-step process, in which CH3Br was prepared from the oxidative bromination reaction of methane in the presence of HBr and oxygen over a Rh-SiO2 catalyst and then, in the second step, CH3Br was hydrolyzed to DME over a silica supported metal chloride catalyst. 12 mol%ZnCl2/SiO2 catalyst was found to be the most active, but it deactivated because of Cl- losing.

关键词： din]ethyl ether methane oxidative bromination methyl bromide catalyst

Preparation of p-1,1,3,3-Tetramethylbutylphenol by Using Nafion-H Catalyst

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Chinese Chemical Letters 2002年第4期13卷 308-310页

作者： Li qin you Guo Rong ZHENG Ping LU Chemistry Department Zhejiang UniversityHangzhou 310027

p-1, 1, 3, 3-Tetramethylbutylphenol was prepared by the alkylation of the phenol with Nafion catalyst in extremely high yield. Various reaction conditions were investigated, including the reaction temperature, reac... 详细信息

关键词： Nafion-H catalyst Friedel-Crafts alkylation synthesis.

Liquefaction susceptibility and deformation characteristics of saturated coral sandy soils subjected to cyclic loadings-a critical review

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 261-296页

作者： Chen Guoxing qin you Ma Weijia Liang Ke Wu Qi C.Hsein Juang Institute of Geotechnical Engineering Nanjing Tech UniversityNanjing 210009China Civil Engineering and Earthquake Disaster Prevention Center of Jiangsu Province Nanjing 210009China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210016China Glenn Department of Civil Engineering Clemson UniversityClemsonSC 29634USA

Coral sandy soils widely exist in coral island reefs and seashores in tropical and subtropical *** to the unique marine depositional environment of coral sandy soils,the engineering characteristics and responses of these soils subjected to monotonic and cyclic loadings have been a subject of intense interest among the geotechnical and earthquake engineering *** paper critically reviews the progress of experimental investigations on the undrained behavior of coral sandy soils under monotonic and cyclic loadings over the last three *** focus of coverage includes the contractive-dilative behavior,the pattern of excess pore-water pressure(EPWP)generation and the liquefaction mechanism and liquefaction resistance,the small-strain shear modulus and strain-dependent shear modulus and damping,the cyclic softening feature,and the anisotropic characteristics of undrained responses of saturated coral sandy *** particular,the advances made in the past decades are reviewed from the following aspects:(1)the characterization of factors that impact the mechanism and patterns of EPWP build-up;(2)the identification of liquefaction triggering in terms of the apparent viscosity and the average flow coefficient;(3)the establishment of the invariable form of strain-based,stress-based,or energy-based EPWP ratio formulas and the unique relationship between the new proxy of liquefaction resistance and the number of cycles required to reach liquefaction;(4)the establishment of the invariable form of the predictive formulas of small strain modulus and strain-dependent shear modulus;and(5)the investigation on the effects of stress-induced anisotropy on liquefaction susceptibility and dynamic deformation *** gained through the critical review of these advances in the past decades offer a perspective for future research to further resolve the fundamental issues concerning the liquefaction mechanism and responses of coral sandy sites subjecte

关键词： liquefaction susceptibility dynamic deformation characteristics coral sandy soil cyclic loading review and prospect

Dynamic Bandwidth Allocation and Rate Coordination for DiffServ Environment

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 248-252页

作者： CHEN Gang WU Guo-xin ZHANG San-feng you Feng-qin Department of Computer Science and Engineering Southeast University Nanjing 210096 Jiangsu China Key Laboratory of Computer Network and Information Integration of MOE Southeast University Nanjing 210096Jiangsu China

This paper presents a novel model for dynamic bandwidth allocation and rate coordination based on DiffServ and a bandwidth broker（BB）. In this model, assignment of bandwidth was made according to a periodic trace of network characteristics per application. And adjustment of transfer rate was accomplished through negotiation with applications by a bandwidth agent. This model was evaluated using network simulator 2 （NS-2）, and distinct improvements were found in respects of delay and packet loss of overall network and single flow. Finally, the model was suggested to be leveraged to multimedia applications with properties of lower delay and lower packet loss.

关键词： QoS bandwidth broker(BB) dynamic bandwidth allocation rate coordination

Subcutaneous versus Intravenous Bortezomib Administration for Multiple Myeloma Patients：a Meta-analysis

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2018年第1期38卷 43-50页

作者： Shi-dai MU Li-sha AI you qin Yu HU Institute of Hematology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China Cancer Center Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China

Bortezomib,the first potent therapeutic proteasome inhibitor,has been suggested as a standard care in patients with newly diagnosed and relapsed multiple myeloma（MM）.However,evidence bearing on the efficacy and safety of subcutaneous（SC） versus intravenous（IV） administration of bortezomib for MM patients is *** controlled trials（RCTs） and observational studies were enrolled in our meta-analysis to investigate the efficacy and safety of bortezomib via SC *** administration on MM *** trials with a total of 2575 patients with MM（SC,n=1191;IV,n=1384） were included in our *** were no significant differences between these two arms regarding overall response rate（ORR）,complete response（CR）,or very good partial response（VGPR）.The pooled RRs for rate of adverse events（AEs）,such as thrombocytopenia and bortezomib-induced peripheral neuropathy（BIPN）,were 0.79（95% CI：0.68–0.92） and 0.63（95% CI：0.51–0.79）,***,there was much more largely decreased incidence of grade 3 and higher thrombocytopenia and BIPN in bortezomib SC administration than IV *** general,alternative SC administration should be considered instead of IV administration in use of bortezomib for patients with MM.

关键词： bortezomib multiple myeloma meta-analysis subcutaneous administration

Quenching and flow of charm and bottom quarks via semi-leptonic decay of D and B mesons in Pb+Pb collisions at the LHC

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Chinese Physics C 2024年第8期48卷 190-197页

作者： Shu-qing Li Wen-Jing Xing Shanshan Cao Guang-you qin School of Physics and Electronic Engineering Jining UniversityQufu 273155China Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China

Heavy flavor particles provide important probes of the microscopic structure and thermodynamic properties of the quark-gluon plasma(QGP)produced in high-energy nucleus-nucleus *** studied the energy loss and flow of charm and bottom quarks inside the QGP via the nuclear modification factor(R_(AA))and elliptic flow coefficient(v_(2))of their decayed leptons in heavy-ion collisions at the *** dynamical evolution of the QGP was performed using the CLVisc(3+1)-dimensional viscous hydrodynamics model;the evolution of heavy quarks inside the QGP was simulated with our improved Langevin model that considers both collisional and radiative energy loss of heavy quarks;the hadronization of heavy quarks was simulated via our hybrid coalescence-fragmentation model;and the semi-leptonic decay of D and B mesons was simulated via *** the same spatial diffusion coefficient for charm and bottom quarks,we obtained smaller R_(AA) and larger v_(2) of charm decayed leptons than bottom decayed leptons,indicating stronger energy loss of charm quarks than bottom quarks inside the QGP within our current model setup.

关键词： quark-gluon plasma heavy-ion collisions jet quenching anisotropic flow heavy quark heavy flavor muon

Pretreatment serum albumin-to-alkaline phosphatase ratio is an independent prognosticator of survival in patients with metastatic gastric cancer

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World Journal of Gastrointestinal Oncology 2022年第5期14卷 1002-1013页

作者： Yu-Ting Li Xiao-Shu Zhou Xiao-Ming Han Jing Tian you qin Tao Zhang Jun-Li Liu Cancer Center Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Ultrasound Medicine Jingmen Second People’s HospitalJingchu University of Technology Affiliated Central HospitalJingmen 448000Hubei ProvinceChina Department of Oncology Hubei Cancer HospitalThe Seventh Clinical School Affiliated of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430000Hubei ProvinceChina

BACKGROUND Previous studies have suggested that a low albumin-to-alkaline phosphatase ratio(AAPR)is associated with a lower survival rate in patients with various ***,the relationship between pretreatment AAPR and the prognosis of patients with gastric cancer(GC)remains *** To investigate the prognostic value of AAPR in distant metastatic *** A total of 191 patients with distant metastatic cancer from a single institute were enrolled in this *** clinical data,including serum albumin and alkaline phosphatase levels,were collected.A chi-square test or Fisher’s exact test was applied to evaluate the correlations between AAPR and various clinical parameters in GC *** Kaplan-Meier method and Cox proportional hazards regression model were used to evaluate the prognostic efficacy of AAPR in metastatic GC patients.A two-sided P value lower than 0.05 was considered statistically *** A receiver operating characteristic curve indicated that 0.48 was the optimal threshold value for ***≤0.48 was significantly associated with bone(P<0.05)and liver metastasis(P<0.05).Patients with high levels of AAPR had better survival in terms of overall survival(OS)and progression-free survival(PFS),regardless of the presence of liver/bone *** AAPR was found to be a favorable predictor of OS and PFS based on a multivariate cox regression ***-M system,constructed based on AAPR and number of metastatic sites,showed superior predictive ability relative to the number of metastatic sites for predicting *** Pretreatment AAPR may serve as an independent prognostic factor for predicting PFS and OS in patients with metastatic ***,AAPR may assist clinicians with individualizing treatment.

关键词： Albumin-to-alkaline phosphatase ratio Gastric cancer overall survival Progression-free survival

Atypical adult-onset Still’s disease with an initial and sole manifestation of liver injury: A case report and review of literature

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World Journal of Clinical Cases 2021年第1期9卷 224-231页

作者： Fan Yu Shao-you qin Chang-Yu Zhou Lu Zhao Yan Xu Er-Na Jia Jiang-Bin Wang Department of Gastroenterology and Hepatology China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Digestive Heze Municipal HospitalHeze 274000Shandong ProvinceChina

BACKGROUND Adult-onset Still's disease(AOSD)typically presents with a high spiking fever,polyarthritis,transient maculopapular rash,neutrophilic leukocytosis,and *** has a wide spectrum of clinical symptoms ranging from mild to severe,with extensive involvement of almost every *** liver involvement in the form of increased hepatic enzymes and bilirubin is common,no AOSD case with liver involvement as the initial manifestation of AOSD has been *** SUMMARY A 35-year-old woman presented to the hepatology department with progressively worsening jaundice for one *** chemistry tests revealed a significantly increased liver enzymes and bilirubin *** that the clinical examination was unremarkable,liver biopsy was considered because the patient had a history of AOSD 6 years *** histopathology revealed that most hepatic lobules were still *** necrosis was observed around most central veins.A few bridging necrotic zones were also *** of multiple plasma cells were observed in the necrotic zone,and the reticular scaffold was still ***,no obvious fibrosis was observed in the portal *** mixed inflammatory cell infiltration was noted in the interstitium of the portal *** examination was unremarkable except for a remarkably high level of ***,a presumptive diagnosis of liver injury secondary to AOSD was *** hepatic involvement responded well to glucocorticoid *** This case highlights that hepatic involvement as an initial and sole manifestation could be a pattern of relapsed *** diagnosis of AOSD should be considered in the case of nonresolving liver injury after the exclusion of common etiologies for liver diseases.A liver biopsy can be useful for the differential diagnosis of liver injury associated with AOSD.

关键词： Adult-onset Still's disease Liver injury Liver biopsy Histopathology Glucocorticoid treatment Case report

Heavy flavor quenching and flow:the roles of initial condition,pre-equilibrium evolution,and in-medium interaction

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Chinese Physics C 2020年第11期44卷 127-137页

作者： Shu-qing Li Wen-Jing Xing Feng-Lei Liu Shanshan Cao Guang-you qin Department of Physics and Information Engineering Jining UniversityQufu 273155China Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Cyclotron Institute Texas A&M UniversityCollege StationTexas77843USA Department of Physics and Astronomy Wayne State UniversityDetroitMichigan 48201USA Nuclear Science Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Within an advanced Langevin-hydrodynamics framework coupled to a hybrid fragmentation-coalescence hadronization model,we study heavy flavor quenching and flow in relativistic heavy-ion *** investigate how the initial heavy quark spectrum,the in-medium energy loss and hadronization mechanisms of heavy quarks,the evolution profile of the pre-equilibrium stage,the medium flow,and the temperature dependence of heavy quark diffusion coefficients influence the suppression and elliptic flow of heavy mesons at the RHIC and the *** results show that the different modeling of initial conditions,pre-equilibrium evolution,and in-medium interactions can individually yield uncertainties of approximately 10-40% in D meson suppression and flow at a low transverse *** also find that proper combinations of collisional versus radiative energy loss,coalescence versus fragmentation in hadronization,and the inclusion of medium flow are the most important factors for describing the suppression and elliptic flow of heavy mesons.

关键词： quark-gluon plasma heavy-ion collisions jet quenching heavy quark