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Control on Crystal Forms of Ultrafine Barium Carbonate Particles and Study on its Mechanism

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1290-1297页

作者： HUO Ji-Chuan LIU Shu-xin yang Ding-ming WANG Hai-Bin Institute of Materials Science and Engineering Southwest University of Science and Technology Mianyang 621010 China

Barium carbonate particles were prepared by using homogeneous precipitation method and co-precipitation method respectively. Through adding different crystalline controlling modifiers, Barium carbonate particles in five different shapes including linear, needle-like, pillarlike, sphere-like and dumbbell-like were synthesized. These particles were characterized by SEM and XRD, and their synthetic mechanism was discussed in this paper.

关键词： barium carbonate crystalline controlling synthesis mechanism

THE COMPARATIVE STUDY OF VENTILATED SUPER CAVITY SHAPE IN WATER TUNNEL AND INFINITE FLOW FIELD

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Journal of Hydrodynamics 2010年第5期22卷 689-696页

作者： ZHOU Jing-jun YU Kai-ping MIN Jing-xin yang ming School of Astronautics Harbin Institute of Technology Harbin 150001 China

In order to understand the difference of ventilated supercavity in water tunnel and infinite flow field, 3-D numerical simulations are carried out to obtain the ventilated supercavity in above mentioned conditions based on RANS equations, using the finite volume method and SST turbulence model in the framework of the two fluid multiphase flow model. The numerical method adopted in this article for the infinite flow field and water tunnel experiments is validated by comparing results with those of empirical formulas and experimental data. On this basis the difference between water tunnel experiments and infinite flow field is studied, including the influence of the route loss and the blocking effect in the water tunnel. Finally, some suggestions are made for water tunnel experiments.

关键词： ventilated supercavity two fluid multiphase model ambient pressure viscous effect blocking effect cavitation number

中药通过调控PI3K-AKT信号通路干预卵巢早衰的研究进展

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广州中医药大学学报 2024年第9期41卷 2508-2514页

作者：赵永涵马红丽杨新鸣黑龙江中医药大学研究生院黑龙江哈尔滨150040 黑龙江中医药大学附属第一医院黑龙江哈尔滨150040

近年来,大量研究证实磷酯酰肌醇3激酶(PI3K)/蛋白激酶B(AKT)信号通路通过调控卵巢细胞的炎症反应、细胞凋亡及自噬、氧化应激、颗粒细胞增殖等过程决定卵泡的闭锁与凋亡,已成为卵巢早衰发生与发展的关键通路。中医药在治疗卵巢早衰等慢... 详细信息

近年来,大量研究证实磷酯酰肌醇3激酶(PI3K)/蛋白激酶B(AKT)信号通路通过调控卵巢细胞的炎症反应、细胞凋亡及自噬、氧化应激、颗粒细胞增殖等过程决定卵泡的闭锁与凋亡,已成为卵巢早衰发生与发展的关键通路。中医药在治疗卵巢早衰等慢性复杂性疾病过程中有明显的优势,而调节PI3K/AKT信号通路是其防治卵巢早衰的作用机制之一。中药可通过调控PI3K-AKT信号通路,抑制卵巢早衰发生与发展过程中的炎症反应,拮抗氧化应激,抑制细胞凋亡及细胞自噬,促进颗粒细胞增殖,从而干预卵巢早衰。该文综述了PI3K/AKT信号通路及其上下游分子在卵巢早衰发病机制中的作用及中药通过PI3K/AKT信号通路干预POF的作用机制,以期为卵巢早衰的基础研究与新药研发提供理论依据。

关键词：卵巢早衰中药 PI3K/AKT信号通路炎症反应细胞凋亡自噬氧化应激细胞增殖综述

Experimental Study of Local Scour Around Four Piles Under Different Attack Angles and Gap Ratios

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China Ocean Engineering 2024年第4期38卷 612-624页

作者： LIU ming-ming TANG Guo-qiang JIN xin GENG Shao-yang School of Architecture and Engineering Liaocheng UniversityLiaocheng 252000China Water-Sediment Regulation and Sand Effective Utilization Special Laboratory of Shandong Provincial Education Department Liaocheng UniversityLiaocheng 252000China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China College of Energy Chengdu University of TechnologyChengdu 610059China

In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental *** research focused on the effects of local scour around a set of four piles,each subjected to different hydromechanical *** particular,this study aimed to determine how different attack angles—the angles at which the water flow impinges on the piles,and gap ratios—the ratios of the spacing between the piles to their diameters,influence the extent and nature of scour.A comprehensive series of 35 carefully designed experiments were orchestrated,each designed to dissect the nuances in how the gap ratio and attack angle might contribute to changes in the local scour observed at the base of pile *** these experimental trials,a wealth of local scour data were collected to support the *** data included precise topographic profiles of the sediment bed around the pile groups,as well as detailed scour time histories showing the evolution of scour at strategic feature points throughout the test *** analysis of the experimental data provided interesting *** study revealed that the interplay between the gap ratio and the attack angle had a pronounced influence on the scouring dynamics of the pile *** of the key observations was that the initial phases of scour,particularly within the first hour of water flow exposure,were characterized by a sharp increase in the scour depth occurring immediately in front of the *** this initial rapid development,the scour depth transitioned to a more gradual change *** contrast,the scour topography around the piles continuously *** suggests that sediment displacement and the associated sculpting of the seabed around pile foundations are sustained and progressive processes,altering the underwater landscape over *** results of this empirical investigation have significant implications for the design and constructio

关键词： local scour piles gap ratio attack angle

Identification and genetic analysis of multiple P chromosomes of Agropyron cristatum in the background of common wheat

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Journal of Integrative Agriculture 2018年第8期17卷 1697-1705页

作者： CHEN Hong-xin HAN Hai-ming LI Qing-feng ZHANG Jin-peng LU Yu-qing yang xin-ming LI Xiu-quan LIU Wei-hua LI Li-hui National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Agronomy Northwest A&F UniversityYangling 712100P.R.China

Agropyron cristatum, a wild relative of common wheat(Triticum aestivum L.), provides many desirable genetic resources for wheat improvement, such as tolerance to cold, drought, and disease. To transfer and utilize these desirable genes, in this study, two wheat-A. cristatum derivatives II-13 and II-23 were identified and analyzed. We found that the number of root tip cell chromosomes was 44 in both II-13 and II-23, but there were four and six P genome chromosomes in II-13 and II-23, respectively, based on genomic in situ hybridization(GISH). The chromosome configurations of II-13 and II-23 were both 2 n=22 II by the meiotic analysis of pollen mother cells(PMCs) at metaphase I, indicating that there were two and three pairs of P chromosomes in II-13 and II-23, respectively. Notably, wheat chromosome 7 D was absent in derivative line II-13 while II-23 lacked chromosomes 4 B and 7 A based on SSR analysis combining fluorescence in situ hybridization(FISH) analysis with p As1 and p Sc119.2 as probes. Chromosomes 2 P and 7 P were detected in both II-13 and II-23. Another pair of P genome chromosomes in II-23 was determined to be 4 P based on expressed-sequences tags-sequence tagged sites(EST-STS) markers specific to A. cristatum and FISH with probes p Ac TRT1 and p Acp CR2. Overall, these results suggest that II-13 was a 7 P(7 D) substitution line with one pair of additional 2 P chromosomes and II-23 was a multiple 4 P(4 B), 7 P(7 A) substitution line with one pair of additional 2 P chromosomes. Moreover, we obtained six alien disomic addition lines and five alien disomic substitution lines by backcrossing. These new materials will allow desirable genes from A. cristatum to be used in common wheat.

关键词： common wheat Agropyron cristatum derivatives in situ hybridization molecular markers

Reaction behavior of MgO refractory with high-Mn and high-Al steel

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Journal of Iron and Steel Research International 2024年第6期31卷 1389-1398页

作者： Ling-zhong Kong Lin Zu Jie yang Xi-min Zang xin yang ming Kang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina

To understand the mechanism of the interfacial reaction between high-Mn and high-Al steel and MgO refractory,a series of laboratory experiments as well as thermodynamic calculations were *** effects of Mn and Al contents in the steel and the reaction time on the interfacial reaction were *** was observed that the erosion of the MgO refractory is caused by the reaction of Al and Mn in the steel with MgO in the refractory,which would lead to the formation of(Mn,Mg)O·Al_(2)O_(3) spinel and(Mn,Mg)O solid *** formation mechanism of the spinel and solid solution is as *** Al in the steel firstly reacts with MgO in the refractory to generate MgO·Al_(2)O_(3) spinel,and then,the spinel reacts with Mn in the steel to form(Mn,Mg)O·Al_(2)O_(3) ***,the MnO in the spinel reacts with the MgO in the inner refractory to form(Mn,Mg)O solid *** addition,only(Mn,Mg)O·Al_(2)O_(3) spinel is present in the interfacial reaction layer of the refractory when the Al content in the steel is sufficient.

关键词： High-Mn high-Al steel MgO refractory Reaction behavior Spinel

Visible Light-Induced[3+2]Annulation Reaction of Alkenes with Vinyl Azides:Direct Synthesis of Functionalized Pyrroles

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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： ming yang xin-Yu Wang Jie Wang Yu-Long Zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye *** substrate scope and high functional group tolerance were demonstrated by more than 50 *** reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Gene and protein expression profiling analysis of young spike development in large spike wheat germplasms

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Journal of Integrative Agriculture 2016年第4期15卷 744-754页

作者： CHEN Dan ZHANG Jin-peng LIU Wei-hua WU Xiao-yang yang xin-ming LI Xiu-quan LU Yu-qing LI Li-hui National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081P.R.China Biotechnology and Germplasm Resources Institute Yunnan Academy of Agricultural SciencesKey Laboratory of Southwestern Crop Gene Resources and Germplasm InnovationMinistry of Agriculture/Scientific Observation for Rice Germplasm Resources of YunnanMinistry of Agriculture/Yunnan Provincial Key Laboratory of Agricultural BiotechnologyKunming 650223P.R.China

The wheat grain number per spike （GNPS） is a major yield-limiting factor in wheat-breeding programs. Germplasms with a high GNPS are therefore valuable for increasing wheat yield potential. To investigate the molecular characteristics of young spike development in large-spike wheat germplasms with high GNPS, we performed gene and protein expression profiling analysis with three high-GNPS wheat lines （Pubing 3228, Pubing 3504 and 4844-12） and one Iow-GNPS control variety （Fukuho）. The phenotypic data for the spikes in two growth seasons showed that the GNPS of the three large-spike wheat lines were significantly higher than that of the Fukuho control line. The Affymetrix wheat chip and isobaric tags for relative and absolute quantitation-tandam mass spectrometry （iTRAQ-MS/MS） technology were employed for gene and protein expression profiling analyses of young spike development, respectively, at the floret primordia differentiation stage. A total of 598 differentially expressed transcripts （270 up-regulated and 328 down-regulated） and 280 proteins （122 up- regulated and 158 down-regulated） were identified in the three high-GNPS lines compared with the control line. We found that the expression of some floral development-related genes, including Wknoxlb, the AP2 domain protein kinase and the transcription factor HUA2, were up-regulated in the high-GNPS lines. The expression of the SHEPHERD （SHD） gene was up-regulated at both the transcript and protein levels. Overall, these results suggest that multiple regulatory pathways, including the CLAVATA pathway and the meristem-maintaining KNOX protein pathway, take part in the development of the high-GNPS phenotype in our wheat germplasms.

关键词： wheat high grain number per spike spike development expression profiling

Neural Network-Based State Estimation for Nonlinear Systems With Denial-of-Service Attack Under Try-Once-Discard Protocol

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2182-2184页

作者： Xueli Wang Shangwei Zhao ming yang xin Wang Xiaoming Wu the Key Laboratory of Computing Power Network and Information Security Ministry of EducationShandong Computer Science CenterQilu University of Technology(Shandong Academy of Sciences)Jinan 250014 Shandong Provincial Key Laboratory of Computer Networks Shandong Fundamental Research Center for Computer ScienceJinan 250014China Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China

Dear Editor,This letter deals with state estimation issues of discrete-time nonlinear systems subject to denial-of-service(DoS)attacks under the try-once-discard(TOD)*** specifically,to reduce the communication burden,a TOD protocol with novel update rules on protocol weights is designed for scheduling measurement *** addition,unknown nonlinear functions vulnerable to DoS attacks are considered due to the openness and vulnerability of the network.

关键词： Service DoS service