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Rare Metals 2010年第5期29卷 465-472页

作者： li Jun yu Zhishui wang Huiping li Manping School of Materials Engineering Shanghai University of Engineering Science Shanghai 201620 China

Titanium-based composite coatings reinforced by in situ synthesized TiB and TiC particles between titanium and B4C were successfully fabricated on Ti6Al4V by laser cladding. Phase constituents of the coatings were predicted by thermodynamic calculations in the Ti-BnC-Al and Ti-B-C-Al systems, respectively, and were validated well by X-ray diffraction （XRD） analysis results. Microstructural and metallographic analyses were made by scanning electron microscopy （SEM） and electron probe micro-analysis （EPMA）. The results show that the coatings are mainly composed of α-Ti cellular dendrites and the eutecticum in which a large number of needle-shaped TiB and a few equiaxial TiC particles are embedded. C is enriched in α-Ti cellular dendrites and far exceeds the theoretical maximum dissolubility, owing to the extension of saturation during laser cladding. The coatings have a good metallurgical bond with the substrate due to the existence of the dilution zone, in which a great amount of lamella β-Ti grains consisting of a thin needle-shaped martensitic microstructure are present and grow parallel to the heat flux direction; a few TiB and TiC reinforcements are observed at the boundaries of initial β-Ti grains.

关键词： composite coatings laser cladding in situ synthesis microstructure thermodynamic calculation

Holocene palynological records and their responses to the controversies of climate system in the Shiyang River drainage basin

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Chinese Science Bulletin 2011年第6期56卷 535-546页

作者： li yu wang NaiAng li ZhuoLun ZHANG HuaAn College of Earth and Environmental Sciences Center for Hydrologic Cycle and Water Resources in Arid Region Lanzhou University Lanzhou730000 China

The Shiyang River drainage basin is located in the northwest margin of the Asian monsoon region. Previous studies reached different conclusions about Holocene climatic changes in the basin. Some studies suggested the Holocene climatic changes were mainly controlled by the Asian monsoon and that the climate was relatively humid during the early Holocene (11.6-7.1 cal ka BP). Other studies found the mid-Holocene Climatic Optimum (7.0-5.0 cal ka BP), and this climate condition was similar to the Holocene westerly wind pattern in arid Central Asia. The modern climate is affected by the Asian monsoon and westerly wind in the drainage basin, and the Holocene climatic records showed two different Holocene climatic patterns-a westerly wind pattern and monsoonal pattern. However, it remains unclear what caused the two different Holocene climatic patterns to co-exist in the region. The palynological records are the main evidence for the Holocene climatic changes in the basin. This paper focuses on palynological records for different parts of the drainage basin. Among them, QTH02, QTL-03 and Sanjiaocheng records are located in the terminal lake, and the Hongshuihe record is located in the middle reaches of the basin. In the terminal lake, the palynological records of QTH02 and QTL-03 are similar, but the Sanjiaocheng record differs. The difference is mainly affected by the variable pollen assemblages in the different locations of the lake basin. From comparison and synthesis of the four palynological records, we concluded that the millennial-scale Holocene climatic changes were affected by the combined effects of the Asian monsoon and westerly wind in the drainage basin, which show the complicated Holocene climatic pattern in the northwest margin of the Asian monsoon.

关键词：中全新世流域盆地孢粉记录气候系统石羊河流域亚洲季风区气候变化反应

Quantifying the adsorption and uptake of CuO nanoparticles by wheat root based on chemical extractions

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Journal of Environmental Sciences 2011年第11期23卷 1852-1857页

作者： Dongmei Zhou Shengyang Jin lianzhen li yu wang Nanyan Weng Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Extensive application of metal nanoparticles is attracting more attention because of their potential environmental *** studies have focused on the uptake of metal nanoparticles （NPs） by plant,but the adsorption of nanoparticles on root surface is often mistakenly regarded as their *** study optimized the methods to distinguish the adsorption and uptake of CuO-NPs on the wheat root by applying different metal competing ions （Na ＋,Mg 2＋,and La 3＋）,surfactant （i.e.,sodium dodecyl benzene sulfonate,SDBS）,or complexing agents like NaOAc and Na 4 EDTA,as well as ultrasonic *** results indicated that some CuO-NPs is strongly adsorbed on the plant root surface,and part of them by mechanical *** ions could not desorb the CuO-NPs from the root surface,while NaOAc and Na 4 EDTA well dissolved the adsorbed *** addition,the uptake and adsorption of CuO-NPs increased with increasing exposure concentrations of CuO-NPs in the range of 5–200 mg/*** amount of CuO-NPs adsorption is always lower than that of their uptake.

关键词： CuO-NPs root surface adsorption uptake

Ammonium Effects on Nitrate Uptake by Roots of Upland and Paddy Rice Seedlings Related to Membrane Potential Differences

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Agricultural Sciences in China 2010年第6期9卷 799-805页

作者： wang Xiao-li wang yu-qian TAO yue-yue FENG Ke College of Environmental Science and Engineering Yangzhou University Yangzhou 225009 P.R. China

Nitrate uptake characteristics and ammonium effects on nitrate uptake were compared between upland rice （Brazilian upland rice） and paddy rice （Wuyujing 3 and Yangdao 6） through the glass microelectrode technique and the concentration gradient method of uptake *** indicated that nitrate uptake by rice seedlings and ammonium effects were depending on membrane potential of root *** upland rice and paddy rice presented obviously different *** all cultivars,the nitrate treatments induced rapid depolarization and then slow repolarization of membrane potential in root epidermal cells,and even hyperpolarization was observed when nitrate concentration was *** membrane potential of epidermal cells in Brazilian upland rice roots was larger and its response to NO3- was bigger than those of two paddy rice *** of membrane potential was amplified when ammonium was simultaneously added with nitrate into the measure medium,but repolarization was reduced,even *** upland rice seedlings had high Vmax of nitrate uptake and low Km,furthermore,Vmax and Km were little affected by ammonium,but Vmax of Wuyujing 3 was reduced ***,inhibition of NH4＋ differed obviously between upland rice and paddy rice.

关键词： nitrate uptake membrane potential ammonium upland rice paddy rice

Plants of Leptostrobus Heer （Czekanowskiales） from the Early Cretaceous and Late Triassic of China, with Discussion of the Genus

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Journal of Integrative Plant Biology 2006年第2期48卷 137-147页

作者： Xiu-Qun liu Cheng-Sen li yu-Fei wang Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Investigation of the Mesozoic seed plant Leptostrobus Heer from the Yangcaogou Formation of the Late Triassic and the Yixian Formation of the Early Cretaceous, liaoning Province, China, provides new Insight Into Its general morphology and geographical distribution. The materials of L. cancer from the Yixian Formation described herein are later than all the past findings of this species and add to the record of L. cancer during the Early Cretaceous. Based on well-preserved specimens, the specific diagnosis Is slightly emended and the reconstructlon of L. cancer Is perfected. The materials from the Yangcaogou Formation of the Late Triassic are placed in L. spheericus, in addition, we review the history of investigation of the genus Leptostrobus since its establishment in 1876 and discuss the main characteristics of each species.

关键词： Early Cretaceous Late Triassic Leptostrobus Yangcaogou Formation Yixian Formation.

Two New Triterpenoids from Saussurea petrovii

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Chinese Chemical Letters 2001年第2期12卷 151-154页

作者： Jing Qiu DAI Bo ZHOU yu li wang li YANG Zhong li liU National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000

Two new taraxastane-type triterpenes. 3 beta. 21 beta -dihydroxyl-20(30)-en-taraxastane 1 and 3 beta. 30-dihydroxy-20(21)-en-taraxastane 2. were isolated from Saussurea petrovii. Their structures were elucidated by sp... 详细信息

关键词： Saussurea petrovii Compositae taraxastane-type triterpenoid 3( 21(-dihydroxyl-20(30)-en-taraxastane 30-dihydroxyl-20(21)-en-taraxastane

Computed tomography combined with gastroscopy for assessment of pancreatic segmental portal hypertension

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World Journal of Clinical Cases 2022年第24期10卷 8568-8577页

作者： yu-li wang Han-Wen Zhang Fan lin Department of Radiology The First Affiliated Hospital of Shenzhen UniversityHealth Science CenterShenzhen Second People’s HospitalShenzhen 518035Guangdong ProvinceChina

BACKGROUND Pancreatic segmental portal hypertension(PSPH) is the only type of portal hypertension that can be completely cured. However, it can easily cause varicose veins in the esophagus and stomach and hemorrhage in the digestive *** To explore the application of computed tomography(CT) to examine the characteristics of PSPH and assess the risk *** This was a retrospective analysis of CT images of 22 patients diagnosed with PSPH at our center. Spearman correlation analysis was performed using the range of esophageal and gastric varices(measured by the vertical gastric wall), the ratio of the width of the splenic portal vein to that of the compression site(S/C ratio), the degree of splenomegaly, and the stage determined by gastroscopy. This study examined whether patients experienced gastrointestinal bleeding within 2 wk and combined CT and gastroscopy to explore the connection between bleeding and CT *** The range of esophageal and gastric varices showed the best correlation in the diagnosis of PSPH(P likely than females to progress to grade 2 or grade 3 as determined by gastroscopy. CT demonstrated excellent performance, with an area under the curve of *** CT can be used to effectively analyze the imaging signs of PSPH, and CT combined with gastroscopy can effectively predict the risk level of gastrointestinal bleeding.

关键词： Computed tomography Pancreatic segmental portal hypertension esophageal and gastric varices Gastrointestinal bleeding Curable portal hypertension

Preparation of Anhydrous LnCl_3(Ln=Eu, Er, Lu) by Chemical Vapor Transport

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Journal of Rare Earths 2000年第2期18卷 152-154页

作者： wang lin shan, li Ying, wang yu hong (Department of Chemistry, Northeastern University, Shenyang 110006, China) Northeastern Univ Dept Chem Shenyang 110006 Peoples R China

Anhydrous lanthanide chlorides LnCl 3(Ln=Eu, Er, Lu) which are not easy to prepare in other ways were prepared by chemical vapor transport(CVT) method. Ln 2O 3 reacted with an excess of Al 2Cl 6 at 300 ℃ to produce LnCl 3. LnCl 3 reacted with Al 2Cl 6 at high temperature to form the gaseous complexes which decomposed at low temperature. LnCl 3 was then separated from other solids by controlling a proper temperature gradient. Residual Al 2Cl 6(g) was removed by the carrier of dry Cl 2 N 2 gases at 200 ℃. The yield rates are >90%, and the purity of products is >99 5%. The high purity of anhydrous lanthanide chlorides can be obtained by CVT method.

关键词： rare earths preparation chemical vapor transport

Enhancing the catalytic efficiency of the Heck coupling reaction by forming 5 nm Pd octahedrons using kinetic control

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Nano Research 2015年第6期8卷 2115-2123页

作者： Ran Long Di Wu Yaping li yu Bai Chengming wang li Song yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale Collaborative Innovation Center of Chemistry for Energy Materials School of Chemistry and Materials Science and National Synchrotron Radiation Laboratory University of Science and Technology ot China Hefei Anhui 230026 China

Heterogeneous catalysis occurs through a process of interfacial reactions; therefore, both surface facet and size control can increase catalytic efficiency. Octahedral Pd nanocrystals, enclosed by {111} facets, should be the ideal geometrical shape for Heck coupling reactions; however, it is challenging to synthesize 5 nm Pd octahedrons with a relatively uniform size distribution using existing capping-agent techniques. Here, we used palladium as a model system to investigate how the kinetics of atomic addition could be precisely controlled using a syringe pump. As a result, our method produced Pd octahedrons as small as 5 nm, which increased the catalytic efficiency of Heck coupling reactions while reducing the weight of catalyst used.

关键词： palladium facet control size control heck-type coupling reaction catalysis

Morinda officinalis oligosaccharides increase serotonin in the brain and ameliorate depression via promoting 5-hydroxytryptophan production in the gut microbiota

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Acta Pharmaceutica Sinica B 2022年第8期12卷 3298-3312页

作者： Zheng-Wei Zhang Chun-Sheng Gao Heng Zhang Jian Yang Ya-Ping wang li-Bin Pan Hang yu Chi-yu He Hai-Bin Luo Zhen-Xiong Zhao Xin-Bo Zhou yu-li wang Jie Fu Pei Han yu-Hui Dong Gang wang Song li Yan wang Jian-Dong Jiang Wu Zhong State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences/Peking Union Medical CollegeBeijing 100050China Beijing Institute of Pharmacology and Toxicology Beijing 100000China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China The National Clinical Research Center for Mental Disorders&Beijing Key Laboratory of Mental Disorders Beijing Anding HospitalCapital Medical UniversityBeijing 100088China Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijing 100069China School of Pharmaceutical Sciences Hainan UniversityHainan 570228China National Engineering Research Center for the Emergence Drugs Beijing 100000China

Morinda officinalis oligosaccharides(MOO) are an oral drug approved in China for the treatment of depression in China. However, MOO is hardly absorbed so that their anti-depressant mechanism has not been elucidated. Here, we show that oral MOO acted on tryptophan → 5-hydroxytryptophan(5-HTP) → serotonin(5-HT) metabolic pathway in the gut microbiota. MOO could increase tryptophan hydroxylase levels in the gut microbiota which accelerated 5-HTP production from tryptophan;meanwhile, MOO inhibited 5-hydroxytryptophan decarboxylase activity, thus reduced 5-HT generation,and accumulated 5-HTP. The raised 5-HTP from the gut microbiota was absorbed to the blood, and then passed across the blood-brain barrier to improve 5-HT levels in the brain. Additionally, pentasaccharide,as one of the main components in MOO, exerted the significant anti-depressant effect through a mechanism identical to that of MOO. This study reveals for the first time that MOO can alleviate depression via increasing 5-HTP in the gut microbiota.

关键词： Depression Morinda oficinalis oligosaccharides Gut microbiota Tryptophan hydroxylase 5-Hydroxytryptophan decarboxylase 5-Hydroxytryptophan Serotonin Drug metabolism