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Chemical Constituents of Phacellaria compressa Benth.

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Journal of Integrative Plant Biology 2006年第2期48卷 236-240页

作者： Xiu-Yun Zhang Bo-Gang Li Min Zhou xiao-hong yuan Guo-Lin Zhang Chengdu Institute of Biology the Chinese Academy of Sciences Chengdu 610041 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China College of Life Sciences Northwest Agricultural University Yangling 712100 China

Two new compounds, 1-（3-methoxy-4-hydroxyphenyl）-3-（3,5-dimethoxy-4-hydroxyphenyl）-propane （1） and 5, 7, 3＇-trlmethyoxyflavan-4＇-O-β-D-glucopyranoslde （2） were Isolated from the ethanol extract of the dried aerial parts of Phacellarla compressa Benth., together with 2,3-bis[（4-hydroxy-3,5-dimethoxyphenyl）-methyl]-1,4- butanedlol （3）, ethyl 3,4,5-trlhydroxybenzoate （4）, methyl 3, 4, 5-trlhydroxybenzoete （5）, β-sltoeterol （6）, 5, 7, 3＇, 4＇- tetrahydroxyfiavan （7）, lupeol （8）, zhebelreslnol （9）, quercetln-3-O-α-L-rhamnopyranoslde （10）, （＋）-cetechin （11）, betulln （12）, β-daucosterol （13）, （＋）-sydngareslnol （14）, scopoletln （15）, and proxlmadlol （16）. The structures of these compounds were determined by spectral evidence or by comparing them with authentic samples. Compound 9 showed α-amylase Inhibitory activity of 57.55% at a concentration of 50 μg/mL.

关键词： α-amylase 1,3-diphenyl-propane flavan-4'-O-β-D-glucopyranoside Phacellaria compressa.

Coevality of the sea-level fall and main mass extinction in the Permian-Triassic transition in Xiushui, Jiangxi Province, southern China

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Journal of Palaeogeography 2014年第3期3卷 309-322页

作者： Ya-Sheng Wu xiao-hong yuan hong-Xia Jiang Li-Jing Liu Key Laboratory of Petroleum Resources Research CAS Institute of Geology and Geophysics Chinese Academy of Sciences Research Institute of Petroleum Exploration and Development PetroChina Huabei Oilfield Company

A continuous Permian-Triassic boundary （PTB） section has been found and studied for the first time in Xiushui, Jiangxi Province, South China. Evidence for a large sealevel fall has been found in the horizon of 0.8 m below the PTB, from the beginning of Hindeodus changxingensis zone （correlatable to Hindeodus typicalis Zone of the Meishan section）. Sedimentary record indicates that the sea level kept at Iowstand, or occasionally rose slowly during the whole Hindeodus parvus zone, except another substantial sea-level fall in early H. parvus zone. It began a quick rise from the beginning of Isarcicella staeschei zone, kept rising for the whole/, staeschei zone, and probably caused the stagnation of sea water. The first severe change in the biota, marked by the sudden disappearance of all steno- tropic organisms such as fusulinids and dasycladacians, happened at the same time as the first sea-level fall, and is regarded as the first and main episode of the end-Permian mass extinction in this area. A microbe-dominated biota followed the first extinction, and spanned the late H. changxingensis zone and the whole H. parvus zone. All the microbes and some other eurytropic organisms including gastropods and ostracods disappeared at the end of the H. parvus zone, and the following biota in the/. staeschei zone is very simple. The coevality of the main sea-level fall and the main extinction episode might be causal： both of them might be caused by a drastic climatic cooling.

关键词： sea-level fall mass extinction Permian-Triassic boundary end-Permian climatic cooling South China

Anion Adsorption on an Au Colloid Monolayer Based Cysteamine-Modified Gold Electrode

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Chemical Research in Chinese Universities 2001年第2期17卷 159-167页

作者： HU xiao-ya, xiao Yi and CHEN hong-yuan (Department of Chemistry, The State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, P. R. China) 南京大学配位化学国家重点实验室江苏南京 210093

Anion adsorption behavior on Au colloid surface was investigated in virture of depositing monolayers of Au colloid on the self-assembled monolayers of cysteamine on a gold electrode. Po- tential-dependent anion adsorption-desorption waves via the nonfaradaic current were obtained by means of cyclic voltammetry at Au coltoid-modified gold electrodes in the potential range of -2 00-600 mV. The adsorption sequence in the order of adsorption peak potentials (Epa) is OH- >citrate3 ->H2PO4- >Cl->SO42->ClO4->NO3-. Among them, citrate3- exhibited an en- tirely irreversible adsorption. A rise in temperature can increase the rates of adsorption-desorp- tion and improve the reversibility of the adsorption-desorption of Cl-, SO42-, ClO4-, NO3- and H2PO-4. The adsorption peak potentials shifted more negatively for Ca. 63 mV as the anion con- centrations were increased by a decade factor. The change of pH from 7 to 1 slightly affected the adsorption peak potentials of Cl- and NO3-. Au colloids with a smaller size (16 nm) gave rise to a better reversibility of the adsorption-desorption process and lower adsorption currents. The ex- perimental results of citrate ions adsorption on Au colloid surface show that Au colloids with a smaller size prepared by sodium citrate method exhibited a higher stability in the solution in com- parison to those with larger sizes because of its higher ratio of charge/mass. In other words, the smaller gold nanoparticles are covered with citrate ions monolayer that can also be formed at larg- er gold nanoparticles by means of electrochemical scan.

关键词： Colloidal gold Self-assembled monolayer Gold electrode Electrode dynamics

Effects of Acute Normovolemic Hemodilution on Perioperative Coagulation and Fibrinolysis in Elderly Patients Undergoing Hepatic Carcinectomy

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Chinese Medical Sciences Journal 2010年第3期25卷 146-150页

作者： Jian-rong Guo Jun Yu xiao-ju Jin Jin-man Du Wei Guo xiao-hong yuan Department of Anesthesiology Lihuili Hospital Medical School of Ningbo University Ningbo 315040 China Department of Anesthesiology Yijishan Hospital Wannan Medical College Wuhu 241001 China

Objective To observe the effects of acute normovolemic hemodilution （ANH） on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy. Methods Thirty elderly patients （aged 60-70 years） with liver cancer （American Society of Anesthesiologists physical status I-II） scheduled for hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group （n= 15） and control group （n= 15）. After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch （HES）（130/0.4）, and basic liquid containing 6% HES and routine Ringer＇s solution, respectively. In all the studied patients, blood samples were drawn at five different time points： before anesthesia induction （T1）, 30 minutes after ANH （T2）, 1 hour after start of operation （T3）, immediately after operation （T4）, and 24 hours after operation （Ts）. Then co- agulation function, soluble fibrin monomer complex （SFMC）, prothrombin fragment （F1＋2）, and platelet membrane glycoprotein （activated GPIIb/GPIIIa and P-selectin） were measured. Results The perioperative blood loss was not significantly different between the two groups （P〉 0.05）. The volume of allogeneic blood transfusion in ANH group was significantly smaller than that in control group （350.5±70.7 mL vs. 457.8±181.3 mL, P〈0.01）. Compared with the data ofT1, prothrombin time （PT） and activated partial thromboplastin time in both groups prolonged significantly after T3 （P〈0.05）, but still within normal range. There were no significant changes in thrombin time and D-dimer between the two groups and between different time points in each group （all P〉0.05）. SFMC and F1 ＋2 increased in both groups, but without statistical significance. P-selectin expression on the platelet surface of ANH group was significantly lowered atT2 andT3 compared with the level atT1 （P〈 0.05）. Compared with control group, P-selectin was sig-nificantly lower in ANH group atT2-T3 （all P〈0.05）. Conclusion

关键词： hepatic carcinectomy acute normovolemic hemodilution coagulationfunction fibrinolysis

Realizing quantum imaginary time evolution in experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 167-168页

作者： xiao yuan Center on Frontiers of Computing Studies Peking UniversityBeijing 100871China School of Computer Science Peking UniversityBeijing 100871China

NISQ,or Noisy Intermediate-Scale Quantum computing,represents a pivotal and the state-of-the-art quantum technology[1].Characterized by intermediate-scale quantum devices that are beyond classical computational capabilities yet fall short of the error-correction thresholds required for fault-tolerant quantum computing,NISQ devices exhibit both promise and *** devices hold immense potential in solving certain computational problems that surpass classical capabilities,with wide applications in optimization,machine learning,and quantum chemistry.

关键词： quantum imaginary correction

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： Xing-yuan Miao hong Zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Data-driven casting defect prediction model for sand casting based on random forest classification algorithm

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China Foundry 2024年第2期21卷 137-146页

作者： Bang Guan Dong-hong Wang Da Shu Shou-qin Zhu xiao-yuan Ji Bao-de Sun Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Hefei Casting and Forging Factory of Anhui Heli Co. LtdHefei 230000China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo *** collected data includes four types of defects and corresponding process parameters were used to construct the RF *** results show a recall rate above 90% for all *** Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF ***,the classification model was applied to different production conditions for quality *** the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature *** prediction model,when applied to the factory,greatly improved the efficiency of defect *** show that the scrap rate decreased from 10.16% to 6.68%.

关键词： sand casting process data-driven method classification model quality prediction feature importance

Singing the Praise of hong Kong's Return——A hong Kong chorus visits Beijing

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Women of China 1997年第7期 21-22页

作者： xiao yuan hong LIU

AN 82-member hong Kong chorus recently held a concert in Beijing to express their happiness at hong Kong’s return to China. The hong Kong Arts Chorus entitled their concert, "When the wind sweeps through, paddy fields produce fragrance to merge both banks--hail the return of hong Kong." The verse which the chorus had adopted as the title of their concert in Beijing comes from a well-known song on the mainland,"My Motherland." By adopting this

关键词： A hong Kong chorus visits Beijing Singing the Praise of hong Kong’s Return

Motor cortical circuit adaptations in parkinsonism

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Neural Regeneration Research 2024年第10期19卷 2107-2108页

作者： hong-yuan Chu Department of Neurodegenerative Science Van Andel Research InstituteGrand RapidsMIUSA Aligning Science Across Parkinson’s(ASAP)Collaborative Research Network

Parkinson's disease is a chronic and progressive neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta,which leads to the featured motor impairment of parki... 详细信息

关键词： parkin impairment rigidity