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Analysis of three types of triterpenoids in tetraploid white birches(Betula platyphylla Suk.) and selection of plus trees

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Journal of Forestry Research 2015年第3期26卷 623-633页

作者： sui Wang Hui Zhao jing Jiang Guifeng Liu Chuanping Yang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry University

Betulin, oleanolic acid, and betulinic acid are naturally occurring pentacyclic triterpenoids that have significant medicinal value. Considerable amounts of these triterpenoids are available in the outer bark of white birch. In this study, we used ultrasound-assisted extraction （UAE） to extract triterpenoids from birch bark rapidly and with high efficiency. Using high performance liquid chro- matography （HPLC）, three types of triterpenoids were separated and detected. We examined the differences among triterpenoids extracted from diploid versus tetra- ploid white birch. Then, we used factor analysis to screen out tetraploid white birches with comprehensively excel- lent performance. The results indicate that the optimum conditions for extraction include the use of ethanol as an extraction solvent, a solid-to-liquid ratio of 0.1 g/10 ml, ultrasonic power set at 100 W, a temperature of 60 ℃ and an extraction time of 15 min. A reversed-phase C18 col- umn （4.6 mm × 250 mm × 5 μm） with a column tem- perature of 30 ℃ and the mobile phase composed of A （acetonitrile） and B （0.1% aqueous phosphoric acid, v/v） at a flow rate of 0.5 ml/min were used, and the detection wavelength was 195 nm. No significant difference wasobserved between diploid and tetraploid white birch in terms of the content of three types of triterpenoids （at a confidence level of 0.05）. As triterpenoid content, height, and DBH （diameter at breast height） are strongly interre- lated, we used factor analysis to evaluate all individuals, and we screened out six plus trees with excellent com- prehensive characters.

关键词： Betula platyphylla Suk Triterpenoids Highperformance liquid chromatography (HPLC) Tetraploid Diploid Factor analysis

Burning products of TA15 titanium alloy by friction oxygen concentration method

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Rare Metals 2018年第11期37卷 952-960页

作者： Nan sui Guang-Bao Mi Meng-Qi Yan jing-Xia Cao Xu Huang Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys AECC Beijing Institute of Aeronautical Materials

The microstructural characteristics, elemental distribution law and microscopic formation mechanism of the burning products of TA15 titanium alloy were investigated by friction oxygen concentration method, associated with in situ observation, X-ray diffraction(XRD),scanning electron microscopy(SEM) and energy-dispersive spectroscopy(EDS) analyses, providing the thoughts to improve fireproof property. The results show that, when the friction contact pressure(p) is 0.20 MPa and oxygen concentration of premixed air flow(c) is 60 vol%, TA15 titanium alloy produces violent sparks and presents dazzling white light during combustion. The generated products after burning are mainly TiOand small amount of AlOoxides. Four distinct zones form from the combustion surface to the alloy matrix, and they are in the sequence of combustion zone, fusion zone, heat-affected zone and transition zone. Further, combustion zone is composed of TiOand A1203 compounds, containing obvious cracks. In the fusion zone, discontinuous oxygenrich Al-based solid solution forms, and the elemental distribution has strong volatility. In the heat-affected zone,there are abundant of Ti-based solid solution and small amount of Al-and Mo-based solid solution. Transition zone is made of lamellar structure. Two technical approaches are given to prevent oxygen diffusion inside the reaction zone and reaction-affected zone. On the one hand,the content of Al is designed as the upper limit of alloy composition; on the other hand, fireproof coatings are deposited on the surface of the alloy.

关键词： Friction oxygen concentration method TA15 titanium alloy Burning products Microstructure Titanium fire

Swaying Tree Simulation by Slicing Partition

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Chinese Journal of Electronics 2020年第5期29卷 826-832页

作者： TANG jing WANG Yinghui WANG Ningna NING Xiaojuan LYU Ke sui Liansheng SHI Zhenghao Faculty of Automation and Information Engineering Xi'an University of Technology School of Artificial Intelligence and Computer Science Jiangnan University The University of Texas at Dallas School of Engineering Sciences University of Chinese Academy of Sciences

The key of swaying tree simulation is to capture the essence of the interaction between wind and tree, which has not received much attention from scholars. In this paper, we present a method for simulating swaying tree based on slicing partition. The tree is divided into multiple "slices", and then jointly moved to simulate the tree swaying in wind. By slicing partition,the motion of any slice is independent of the others concurrently, which provides a parallel spatial topology for real-time calculation. Moreover, based on the fact that the wind will blow to a tree partly rather than the whole, partial swayings of the tree are also simulated. The experimental results show the correctness and effectiveness of our method.

关键词： Tree swaying Slicing Damping

Introduction of a New Method for Regulating Laves Phases in Inconel 718 Superalloy during a Laser-Repairing Process

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Engineering 2022年第9期16卷 239-246页

作者： Shang sui Haosheng Li Zuo Li Xuan Zhao Liang Ma jing Chen State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China

The morphology,size,and distribution of Laves phases have important influences on the mechanical properties of laser-repaired Inconel 718(IN718)*** to the deterioration of the substrate zone,the Laves phase in the laser cladding zone of IN718 superalloy cannot be optimized by a hightemperature solution *** this study,an in situ laser heat-treatment method was proposed to regulate the morphology and size of the Laves phase in the laser cladding zone of IN718 superalloy without impacting the substrate *** the in situ laser heat-treatment process,a laser was used to heat previously deposited layers with optimized manufacturing parameters.A thermocouple and an infrared camera were used to analyze thermal cycles and real-time temperature fields,*** and micro-segregations were observed by optical microscopy,scanning electron microscopy,and electron probe *** was found that the in situ laser heat treatment effectively changed the morphology and size of the Laves phase,which was transformed from a continuous striplike shape to a discrete granular *** effective temperature range and duration were the two main factors influencing the Laves phase during the in situ laser heat-treatment *** effective temperature range was determined by the laser linear energy density,and the peak temperature increased with the increase of the linear energy *** addition,the temperature amplitude could be reduced by simultaneously increasing the laser power and the scanning ***,a flow diagram was developed based on the in situ laser heat-treatment process,and the deposition of a single-walled sample with fine and granular Laves phases was detected.

关键词： Laser repair In situ laser heat treatment Inconel 718 alloy Laves phase

Origin of Baotoudong syenites in North China Craton:Petrological, mineralogical and geochemical evidence

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Science China Earth Sciences 2016年第1期59卷 95-110页

作者： NIU Xiao Lu YANG jing sui LIU Fei ZHANG Hong Yu YANG Ming Chun State Key Laboratory of Continental Tectonics and Dynamics Institute of Geology Chinese Academy of Geological Sciences Institute of Earth Sciences China University of Geosciences Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking University

Baotoudong syenite pluton is located to the east of Baotou City, Inner Mongolia, the westernmost part of the Trias- sic alkaline magmatic belt along the northern margin of the North China Craton （NCC）. Zircon U-Pb age, petrological, miner- alogical and geochemical data of the pluton were obtained in this paper, to constrain its origin and mantle source characteris- tics. The pluton is composed of nepheline-clinopyroxene syenite and alkali-feldspar syenite, with zircon U-Pb age of 214.7±1.1 Ma. Diopside （cores）-aegirine-augite （rims）, biotite, orthoclase and nepheline are the major minerals. The Bao- toudong syenites have high contents of rare earth elements （REE）, and are characterized by enrichment in light rare earth ele- ments （LREE） and large ion lithophile elements （LILE; e.g., Rb, Ba, Sr）, depletion in heavy rare earth elements （HREE） and high field strength elements （HFSE）. They show enriched Sr-Nd isotopic compositions with initial 87Sr/86Sr ranging from 0.7061 to 0.7067 and eNd（t） values from -9.0 to -11.2. Mineralogy, petrology and geochemical studies show that the parental magma of the syenites is SiO2-undersaturated potassic-ultrapotassic, and is characterized by high contents of CaO, Fe2O3, K2O, Na2O and fluid compositions （H2O）, and by high temperature and high oxygen fugacity. The syenites were originated from a phlogopite-rich, enriched lithospheric mantle source in garnet-stable area （〉80 km）. The occurrence of the Baotoudong sye- nites, together with many other ultrapotassic, alkaline complexes of similar ages on the northern margin of the NCC in Late Triassic implies that the lithospheric mantle beneath the northern margin of the NCC was previously metasomatized by melts/fluids from the subducted, altered paleo-Mongolian oceanic crust, and the northern margin of the craton has entered into an extensively extensional regime as a destructive continental margin in Late Triassic.

关键词： Zircon U-Pb age Mineralogy Geochemistry Baotoudong syenites Ultrapotassic alkaline rocks Triassic Mantlemetasomatism North China Craton

Refractory humic-like dissolved organic matter fuels microbial communities in deep energy-limiting marine sediments

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Science China Earth Sciences 2023年第8期66卷 1738-1756页

作者： Yunru CHEN Weikang sui jing WANG Ding HE Liang DONG Joanna JWANIEK Fengping WANG State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Department of Ocean Science and the Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) The Hong Kong University of Science and TechnologyHong Kong 999077China School of Earth Sciences Zhejiang UniversityHangzhou 310027China Leibniz Institute for Baltic Sea Research WarnemündeRostock 18119Germany

Humic-like dissolved organic matter(DOM),usually regarded as refractory,is a major component of DOM in marine sediment pore ***,its bio-reactivity remains poorly explored in natural environments,which makes its roles in supporting subsurface microbial communities and regulating long-term carbon cycling ***,the bio-reactivity of humiclike DOM was evaluated by modeled reaction rates together with its interactions with microbial communities in five sediment cores collected from the eutrophic Pearl River Estuary to the oligotrophic deep-sea basin in the northern South China *** revealed contrasting relationships between humic-like DOM and microbes in the coastal and deep-sea *** eutrophic coastal sediments,specific microbial groups enriched in the deep layers co-varied with humic-like DOM,while most microbial groups were significantly correlated with protein-like DOM,microbial transformation of which likely resulted in the production of humic-like *** the contrary,in energy-limiting deep-sea sediments,over 70%of the microbial groups were found closely correlated with humic-like DOM,a net consumption of which was demonstrated in deep *** consumption of humic-like DOM in deep-sea sediments reduced its total production flux in the uppermost~5-meter layer to about one-tenth of that in coastal sediments,which could consequently decrease the refractory DOM flux to the overlying seawater and influence long-term oceanic carbon cycling.

关键词： Fluorescent dissolved organic matter Subsurface microbial communities Marine sediments Microbial transformation Oceanic carbon cycling

Transient emission simulation and optimization o turbocharged diesel engine

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Frontiers in Energy 2013年第2期7卷 237-244页

作者： Lingge sui Zhongchang LIU Yongqiang HAN jing TIAN State Key Laboratory of Automotive Simulation and Control JilinUniversity Changchun 130025 China Computer Department Changchun Finance College Changchun130028 China

In order to alleviate the pressure of experi- mental research of turbocharged diesel engine under transient operations, a whole process simulation platform for turbocharged diesel engine under transient operations was established based on the multi-software coupling technologies of Matlab/Simulink, GT-Power, STAR-CD and artificial neural network. Aimed at the contradiction of NOx and soot emission control with exhaust gas recirculation （EGR） of turbocharged diesel engine under transient operations, on this simulation platform, a transient EGR valve control strategy was proposed, which adjusted the EGR valve in adjacent level based on the feedback of its opening according soot control limit under transient operations. Simulation and experimental results prove that the transient emission optimization effect of this control strategy is obvious. On the one hand, compared with the previous control strategy, which closed the EGR valve during the whole transient operations, soot emission is slightly increased by 9.5%, but it is still 9% lower than the control limit. On the other hand, compared with the previous control strategy, NOx transient emission is reduced by 44%.

关键词： diesel engine transient simulation emission control strategy exhaust gas recirculation (EGR)

Transjugular intrahepatic portosystemic shunt for the prevention of recurrent esophageal variceal bleeding in patients with cavernous transformation of portal vein

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 517-523页

作者： Zhao-Peng Li sui-sui Wang Guang-Chuan Wang Guang-Jun Huang jing-Qin Cao Chun-Qing Zhang Department of Gastroenterology Shandong Provincial Hospital Affiliated to Shandong UniversityJinan 250021China Department of Interventional Radiology Jining No.1 People’s HospitalJining 272011China Department of Pediatrics The Affiliated Hospital of Jining Medical CollegeJining 272000China

Background: Treatment options for patients with cavernous transformation of portal vein(CTPV) are limited. This study aimed to evaluate the feasibility, efficacy and safety of transjugular intrahepatic portosystemic shunt(TIPS) to prevent recurrent esophageal variceal bleeding in patients with CTPV. Methods: We retrospectively analyzed 67 consecutive patients undergone TIPS from January 2011 to December 2016. All patients were diagnosed with CTPV. The indication for TIPS was a previous episode of variceal bleeding. The data on recurrent bleeding, stent patency, hepatic encephalopathy and survival were retrieved and analyzed. Results: TIPS procedure was successfully performed in 56 out of 67(83.6%) patients with CTPV. TIPS was performed via a transjugular approach alone( n = 15), a combined transjugular/transhepatic approach( n = 33) and a combined transjugular/transsplenic approach( n = 8). Mean portosystemic pressure gradient(PSG) decreased from 28.09 ± 7.28 mmHg to 17.53 ± 6.12 mmHg after TIPS( P < 0.01). The probability of the remaining free recurrent variceal bleeding was 87.0%. The probability of TIPS patency reached 81.5%. Hepatic encephalopathy occurrence was 27.8%, and survival rate was 88.9% until the end of follow-up. Four out of 11 patients who failed TIPS died, and 4 had recurrent bleeding. Conclusions: TIPS should be considered a safe and feasible alternative therapy to prevent recurrent esophageal variceal bleeding in patients with CTPV, and to achieve clinical improvement.

关键词： Cavernous transformation Portal vein Transjugular intrahepatic portosystemic shunt Variceal rebleeding Portal hypertension

Role of interleukin-22 in inflammatory bowel disease

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World Journal of Gastroenterology 2014年第48期20卷 18177-18188页

作者： Lin-jing Li Chen Gong Mei-Hua Zhao Bai-sui Feng Department of Gastroenterology the Fifth Affiliated Hospital of Zhengzhou University

Inflammatory bowel disease (IBD) is a chronic inflammatory disease thought to be mediated by the microbiota of the intestinal lumen and inappropriate immune responses. Aberrant immune responses can cause secretion of harmful cytokines that destroy the epithelium of the gastrointestinal tract, leading to further inflammation. Interleukin (IL)-22 is a member of the IL-10 family of cytokines that was recently discovered to be mainly produced by both adaptive and innate immune cells. Several cytokines and many of the transcriptional factors and T regulatory cells are known to regulate IL-22 expression through activation of signal transducer and activator of transcription 3 signaling cascades. This cytokine induces antimicrobial molecules and proliferative and antiapoptotic pathways, which help prevent tissue damage and aid in its repair. All of these processes play a beneficial role in IBD by enhancing intestinal barrier integrity and epithelial innate immunity. In this review, we discuss recent progress in the involvement of IL-22 in the pathogenesis of IBD, as well as its therapeutic potential.

关键词： Inflammatory bowel disease Interleukin-22 Signal transducer and activator of transcription 3