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Design and Fluid-Dynamic Analysis of a Flushing Nozzle for Drilling Applications

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Fluid Dynamics & Materials Processing 2023年第12期19卷 2953-2963页

作者： Zhongshuai chen Hongjian Ni Xueliang Pei yu Gao School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China Drilling Technology Research Institute of Shengli Petroleum Engineering Co. Ltd.SinopecDongying257000China Shenzhen South China Sea Oil Economic Development Company Shenzhen518000China

The actuator is a key component of the creaming tool in drilling *** jet performances determine the effective reaming *** this work,a new selective reaming tool is proposed and the RNG k-εturbulence model is used to calculate its internal and *** particular,special attention is paid to the design of theflushing *** results show that the jet originating from theflushing nozzle has a significant influence on rock cutting and blade cooling *** turn,the jet performances depend on geometric structure of the creaming *** this framework,a conical-cylindrical nozzle with a diameter of 7 mm is initially considered as a basis to implement a strategy to optimize the structural parameters of the reaming actuator,and improve the related side tracking reconstruction technology.

关键词： Reaming tool while drilling flowfluid characteristics flushing nozzle nozzle structure

Two new saponins from the aerial part of Astragalus membranaceus var. mongholicus

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Chinese Chemical Letters 2007年第5期18卷 554-556页

作者： Qing Tao yu Ping Li Zhi ming Bi Jun Luo Xiao Dan Gao Key Laboratory of Modern Chinese Medicines Ministry of Education Nanjing 210038 China Department of Pharmacognosy China Pharmaceutical University Nanjing 210038 China

Two new saponins named mongholicoside A （1） and mongholicoside B （2） were isolated from the aerial part of Astragalus membranaceus var mongholicus. Their structures were determined by 1D and 2D NMR, ESI-MS techniq... 详细信息

关键词： Astragalus membranaceus vat. mongholicus Aerial part Triterpene saponin Mongholicoside A and B

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Neural Regeneration Research 2010年第16期5卷 1231-1237页

作者： Jianming Jiang Long yu Yangtai Guan Zhiliang yu Xinghua Huang Xiaosong chen LishaTang Xianning Zhang Department of Neurology Changhai Hospital Second Military Medical University Shanghai 200433 China State Key Laboratory of Genetic Engineering Institute of Genetics School of Life Science Fudan University Shanghai 200433 China Zhejiang University-Adinovo Center for Genetic and Genomic Medicine Zhejiang University School of Medicine Hangzhou 310058 Zhejiang Province China

Epilepsy is a complex, Mendelian disease, and most cases are sporadic. Genomic comparisons of tissue from identified monogenic epilepsies with multigenic and acquired syndromes could ultimately reveal crucial molecular neuropathology for an epileptic phenotype. In the present study, a novel gene, human seizure-related （hSEZ）-6, was isolated from a human brain cDNA library. hSEZ-6 comprises 17 exons and spans a region of at least 55.6 kb, which was localized to 17q 12 by radiation hybridization, hSEZ-6 exhibits two isoform types, hSEZ-6A and hSEZ-6B, which encode 996 and 995 amino acids, respectively. The two putative hSEZ-6 proteins contain similar motifs and share 82% and 84% identity with mouse SEZ-6A protein, whose expression level increased in mouse cerebral cortex-derived cells treated with a convulsant drug, pentylentetrazole. Northern blot analysis demonstrated that hSEZ-6 is expressed highly in the cerebellum and in nucleus of the extrapyramidal system, such as the caudate nucleus and putamen. Reverse transcription polymerase chain reaction revealed that hSEZ-6 is expressed in neurons rather than gliocytes, which suggests that hSEZ-6 is a seizure-related gone.

关键词： seizures epilepsy human seizure-related-6 gene cloning brain-specific expression cerebellum

Synthesis and characterization of carbazole-based dendrimers as bipolar host materials for green phosphorescent organic light emitting diodes

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Chinese Chemical Letters 2016年第3期27卷 441-446页

作者： Ting Zhang Dong-Qing Xu Jun-ming chen Ping Zhang Xu-Chun Wang School of Chemistry and Material Engineering Anhui Science and Technology University Center of Analysis and Measurement Anhui Science and Technology University

A group of novel, carbazole-based dendrimers comprised of the electron-accepting dibenzothiophene core and the electron-donating oligo-carbazole dendrons, namely G1 SF and G2 SF, are synthesized utilizing the Ullmann C–N coupling reaction. The dendrimers are designed in such a way to show good solubility in common organic solvents, excellent thermochemical stability with decomposition temperatures（Td） up to430 8C, and high HOMO levels in a range from 5.45 e V to 5.37 e V. Results of density functional theory calculations（DFT） indicate G2 SF has an almost complete separation of HOMO and LUMO levels at the holeand electron-transporting moieties; while G1 SF exhibits only partial separation of the HOMO and LUMO levels possibly due to intramolecular charge transfer. Green phosphorescent OLEDs were fabricated by the spin coating method with the dendrimers as hosts and traditional green iridium phosphor as doped emitter. Under ambient conditions, a maximum luminance efficiency（hL） of 19.83 cd A^-1and a maximum external quantum efficiency of 5.85% are achieved for G1 SF, and 15.50 cd A ^-1and 4.57% for G2 SF.

关键词： OLEDs Bipolar host materials Dendrimer Carbazole Dibenzothiophene

Spatial distribution of snow depth based on geographically weighted regression kriging in the Bayanbulak Basin of the Tianshan Mountains, China

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Journal of Mountain Science 2018年第1期15卷 33-45页

作者： LIU Yang LI Lan-hai chen Xi YANG Jin-ming HAO Jian-Sheng State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China CAS Research Center for Ecology and Environment of Central Asia No.818 South Beijing Road Urumqi 830011 China Institute of Arid Ecology and Environment Xinjiang University Urumqi 830046 China

Snow depth is a general input variable in many models of agriculture,hydrology,climate and *** study makes use of observational data of snow depth and explanatory variables to compare the accuracy and effect of geographically weighted regression kriging(GWRK)and regression kriging(RK)in a spatial interpolation of regional snow *** auxiliary variables are analyzed using correlation coefficients and the variance inflation factor(VIF).Three variables,Height,topographic ruggedness index(TRI),and land surface temperature(LST),are used as explanatory variables to establish a regression model for snow *** estimated spatial distribution of snow depth in the Bayanbulak Basin of the Tianshan Mountains in China with a spatial resolution of 1 km is *** results indicate that 1)the result of GWRK's accuracy is slightly higher than that of RK(R^2=0.55 vs.R^2=0.50,RMSE(root mean square error)=0.102 m ***=0.077 m);2)for the subareas,GWRK and RK exhibit similar estimation results of snow *** in the Bayanbulak Basin with a snow depth greater than 0.15m are mainly distributed in an elevation range of 2632.00–3269.00 m and the snow in this area comprises 45.00–46.00% of the total amount of snow in this ***,the GWRK resulted in more detailed information on snow depth distribution than the *** final conclusion is that GWRK is better suited for estimating regional snow depth distribution.

关键词： Snow depth Spatial distribution Regression kriging Geographically weighted regression kriging

Why are halo coronal mass ejections faster?

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Research in Astronomy and Astrophysics 2010年第5期10卷 461-472页

作者： Qing-Min Zhang Yang Guo Peng-Fei chen ming-De Ding cheng Fang Department of Astronomy Nanjing University Nanjing 210093 China Key Laboratory of Modem Astronomy and Astrophysics Ministry of Education Nanjing210093 China

Halo coronal mass ejections （CMEs） have been to be significantly faster than normal CMEs, which is a long-standing puzzle. In order to solve the puzzle, we first investigate the observed properties of 31 limb CMEs that clearly display loopshaped frontal loops. The observational results show a strong tendency that slower CMEs are weaker in white-light intensity. Then, we perform a Monte Carlo simulation of 20000 artificial limb CMEs that have an average velocity of ～523km s -1. The Thomson scattering of these events is calculated when they are assumed to be observed as limb and halo events, respectively. It is found that the white-light inten-sity of many slow CMEs becomes remarkably reduced when they turn from being viewed as a limb event to being viewed as a halo event. When the intensity is below the background solar wind fluctuation, it is assumed that they would be missed by coronagraphs. The average velocity of ＂detectable＂ halo CMEs is ～922km s -1, very close to the observed value. This also indicates that wider events are more likely to be recorded. The results soundly suggest that the higher average velocity of halo CMEs is due to that a majority of slow events and some of narrow fast events carrying less material are so faint that they are blended with the solar wind fluctuations, and therefore are not observed.

关键词： Sun: coronal mass ejections (CMEs) — Sun: activity — methods: nu-merical — solar-terrestrial relations

Metabolic Acidosis in Critically Ill Cirrhotic Patients with Acute Kidney Injury

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Journal of Clinical and Translational Hepatology 2019年第2期7卷 112-121页

作者： Dan-Qin Sun Lai Zhang chen-Fei Zheng Wen-yue Liu Kenneth I.Zheng Xiao-ming chen ming-Hua Zheng Wei-Jie yuan Department of Nephrology The Affiliated Wuxi No.2 People’s Hospital of Nanjing Medical UniversityWuxiChina Department of Nephrology Shanghai General Hospital of Nanjing Medical UniversityShanghaiChina Department of Nephrology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina Department of Endocrinology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina NAFLD Research Center Department of Hepatologythe First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina Zhejiang Engineering Research Center of Intelligent Medicine The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina Institute of Hepatology Wenzhou Medical UniversityWenzhouChina Key Laboratory of Diagnosis and Treatment of Severe Hepato-Pancreatic Diseases of Zhejiang Province WenzhouChina

Background and Aims:The metabolic acid-base disorders have a high incidence of acute kidney injury(AKI)in critically ill cirrhotic patients(CICPs).The aims of our study were to ascertain the composition of metabolic acidosis of CICPs with AKI and explore its relationship with hospital ***:Three-hundred and eighty consecutive CICPs with AKI were eligible for the cohort ***,clinical and laboratory parameters were recorded and arterial acid-base state was analyzed by the Stewart and Gilfix ***:Net metabolic acidosis,lactic acidosis,acidosis owing to unmeasured anions,acidemia,and dilutional acidosis were less frequent in the non-survival group compared to the survival group of *** presence of acidemia,acidosis owing to unmeasured anions,and lactic acidosis were independently associated with increased risk of intensive care unit 30-day mortality,with hazard ratios of 2.11(95%confidence interval(CI):1.43–3.12),3.38(95%CI:2.36–4.84),and 2.16(95%CI:1.47–3.35),*** full adjustment for confounders,the relationship between acidosis owing to unmeasured anions with hospital mortality was still significant,with hazard ratio of 2.29(95%CI:1.22–4.30).Furthermore,arterial lactate concentration in combination with chronic liver failure-sequential organ failure assessment and BEUMA had the strongest ability to differentiate 30-day mortality(area under the receiver operating characteristic curve:0.79,95%CI:0.74–0.83).

关键词： Metabolic acidosis Critically ill cirrhotic patients Acute kidney injury Hospital morality

The Synthesis of Tertiary Amides by theReaction of Adducts of Schiff Bases andAcyl Chlorides with Allylsamarium Bromide

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Chinese Chemical Letters 1999年第1期10卷 9-10页

作者： ming Xin yu Yong Min ZHANG(Department of Chemistry. Zhejiang University, Hangzhou, 310028) Department of Chemistry Zhejiang University Hangzhou 310028 China

Adducts of Schiff bases and acyl chlorides react with allylsamarium bromide to afford the corresponding tertiary amides.

关键词： Allylsamarium bromide tertiary amides Schiff bases acyl chloride synthesis

Laser Diagnostics of Combustion Enhancement on a CH4/Air Bunsen Flame by Dielectric Barrier Discharge

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Chinese Physics Letters 2013年第8期30卷 114-117页

作者： ZHANG Shao-Hua yu Xi-Long chen Li-Hong ZHANG Xin-yu Institute of Mechanics Chinese Academy of SciencesBeijing 100190

We investigate plasma-assisted combustion for premixed CH4/air Bunsen *** barrier discharge(DBD)is employed to produce non-equilibrium plasma for combustion *** transient planar laser induced fluorescence(PLIF)technique of CH and OH radicals is used to image reaction zones for enhancement measurement,and the emission spectra of the Bunsen flame are monitored to explore the kinetics *** the drift of radicals in PLIF images,the quantitative enhancement of plasma on the flame velocities of premixed methane/air flames is experimentally measured,and the data show that the flame velocities are increased by at least 15%in the presented equivalence ratio ***,the well analyzed emission spectra of the Bunsen flame(300–800 nm)with/without DBD reveal that the emissions as well as the concentrations of the crucial radicals(like C2,CH,OH etc.)in combustion all are intensified greatly by the *** addition,the appearance of excited spectral bands of N2 and N2+during discharge indicates that the premixed gas is also heated and ionized partially by the DBD.

关键词： intensified heated kinetics